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Sample records for inhibitor sorafenib induces

  1. Sorafenib, a multikinase inhibitor, induces formation of stress granules in hepatocarcinoma cells

    PubMed Central

    Adjibade, Pauline; St-Sauveur, Valérie Grenier; Huberdeau, Miguel Quevillon; Fournier, Marie-Josée; Savard, Andreanne; Coudert, Laetitia; Khandjian, Edouard W.; Mazroui, Rachid

    2015-01-01

    Stress granules (SGs) are cytoplasmic RNA multimeric bodies that form under stress conditions known to inhibit translation initiation. In most reported stress cases, the formation of SGs was associated with the cell recovery from stress and survival. In cells derived from cancer, SGs formation was shown to promote resistance to either proteasome inhibitors or 5-Fluorouracil used as chemotherapeutic agents. Despite these studies, the induction of SGs by chemotherapeutic drugs contributing to cancer cells resistance is still understudied. Here we identified sorafenib, a tyrosine kinase inhibitor used to treat hepatocarcinoma, as a potent chemotherapeutic inducer of SGs. The formation of SGs in sorafenib-treated hepatocarcionoma cells correlates with inhibition of translation initiation; both events requiring the phosphorylation of the translation initiation factor eIF2α. Further characterisation of the mechanism of sorafenib-induced SGs revealed PERK as the main eIF2α kinase responsible for SGs formation. Depletion experiments support the implication of PERK-eIF2α-SGs pathway in hepatocarcinoma cells resistance to sorafenib. This study also suggests the existence of an unexpected complex regulatory balance between SGs and phospho-eIF2α where SGs dampen the activation of the phospho-eIF2α-downstream ATF4 cell death pathway. PMID:26556863

  2. STAT3-mediated attenuation of CCl4-induced mouse liver fibrosis by the protein kinase inhibitor sorafenib.

    PubMed

    Deng, Yan-Ru; Ma, Hong-Di; Tsuneyama, Koichi; Yang, Wei; Wang, Yin-Hu; Lu, Fang-Ting; Liu, Cheng-Hai; Liu, Ping; He, Xiao-Song; Diehl, Anna Mae; Gershwin, M Eric; Lian, Zhe-Xiong

    2013-10-01

    There have been major advances in defining the immunological events associated with fibrosis in various chronic liver diseases. We have taken advantage of this data to focus on the mechanisms of action of a unique multi-kinase inhibitor, coined sorafenib, on CCl4-induced murine liver fibrosis, including the effects of this agent in models of both acute and chronic CCl4-mediated pathology. Importantly, sorafenib significantly attenuated chronic liver injury and fibrosis, including reduction in liver inflammation and histopathology as well as decreased expression of liver fibrosis-related genes, including α-smooth muscle actin, collagen, matrix metalloproteinases and the tissue inhibitor of metalloproteinase-1. Furthermore, sorafenib treatment resulted in translocation of cytoplasmic STAT3 to the nucleus in its active form. Based on this observation, we used hepatocyte-specific STAT3 knockout (STAT3(Hep-/-)) mice to demonstrate that hepatic STAT3 was critical for sorafenib-mediated protection against liver fibrosis, and that the upregulation of STAT3 phosphorylation was dependent on Kupffer cell-derived IL-6. In conclusion, these data reflect the clinical potential of the multi-kinase inhibitor sorafenib for the prevention of fibrosis as well as the treatment of established liver fibrosis and illustrate the immunological mechanisms that underlie the protective effects of sorafenib. PMID:23948302

  3. Sorafenib induced eruptive melanocytic lesions.

    PubMed

    Uhlenhake, Elizabeth E; Watson, Alice C; Aronson, Peter

    2013-05-01

    Sorafenib is a multikinase inhibitor FDA-approved for the treatment of advanced renal cell and hepatocellular carcinoma. Dermatologic side effects include hand-foot skin reaction, facial and scalp erythema and desquamation, splinter subungual hemorrhages, alopecia, pruritus, xerosis, keratoacanthomas, and squamous cell carcinomas. We report sudden eruption of melanocytic nevi diffusely in a patient receiving sorafenib. PMID:24011281

  4. Radiation-induced hemorrhagic duodenitis associated with sorafenib treatment.

    PubMed

    Yanai, Shunichi; Nakamura, Shotaro; Ooho, Aritsune; Nakamura, Shigeo; Esaki, Motohiro; Azuma, Koichi; Kitazono, Takanari; Matsumoto, Takayuki

    2015-06-01

    Sorafenib, an oral inhibitor of multiple tyrosine kinase receptors, has been widely used as a standard medical treatment for advanced hepatocellular carcinoma (HCC). Here, we report a 66-year-old male patient who developed gastrointestinal bleeding due to radiation-induced hemorrhagic duodenitis associated with sorafenib treatment. We started oral administration of sorafenib because of the recurrence of HCC with lung metastases. The patient had been treated by radiotherapy for para-aortic lymph node metastases from HCC 4 months before the bleeding. Esophagogastroduodenoscopy (EGD) revealed edematous reddish mucosa with friability and telangiectasia in the second portion of the duodenum. Computed tomography and capsule endoscopy revealed that the hemorrhagic lesions were located in the distal duodenum. After discontinuation of sorafenib, the bleeding disappeared and a follow-up EGD confirmed improvement of duodenitis. Based on these findings, the diagnosis of radiation-induced hemorrhagic duodenitis associated with sorafenib was made. PMID:25832768

  5. Sorafenib enhances proteasome inhibitor-mediated cytotoxicity via inhibition of unfolded protein response and keratin phosphorylation

    SciTech Connect

    Honma, Yuichi; Harada, Masaru

    2013-08-15

    Hepatocellular carcinoma (HCC) is highly resistant to conventional systemic therapies and prognosis for advanced HCC patients remains poor. Recent studies of the molecular mechanisms responsible for tumor initiation and progression have identified several potential molecular targets in HCC. Sorafenib is a multi-kinase inhibitor shown to have survival benefits in advanced HCC. It acts by inhibiting the serine/threonine kinases and the receptor type tyrosine kinases. In preclinical experiments sorafenib had anti-proliferative activity in hepatoma cells and it reduced tumor angiogenesis and increased apoptosis. Here, we demonstrate for the first time that the cytotoxic mechanisms of sorafenib include its inhibitory effects on protein ubiquitination, unfolded protein response (UPR) and keratin phosphorylation in response to endoplasmic reticulum (ER) stress. Moreover, we show that combined treatment with sorafenib and proteasome inhibitors (PIs) synergistically induced a marked increase in cell death in hepatoma- and hepatocyte-derived cells. These observations may open the way to potentially interesting treatment combinations that may augment the effect of sorafenib, possibly including drugs that promote ER stress. Because sorafenib blocked the cellular defense mechanisms against hepatotoxic injury not only in hepatoma cells but also in hepatocyte-derived cells, we must be careful to avoid severe liver injury. -- Graphical abstract: Display Omitted -- Highlights: •We examined the cytotoxic mechanisms of sorafenib in hepatoma cells. •Sorafenib induces cell death via apoptotic and necrotic fashion. •Sorafenib inhibits protein ubiquitination and unfolded protein response. •Autophagy induced by sorafenib may affect its cytotoxicity. •Sorafenib inhibits keratin phosphorylation and cytoplasmic inclusion formation.

  6. Sorafenib-induced defective autophagy promotes cell death by necroptosis

    PubMed Central

    Kharaziha, Pedram; Chioureas, Dimitris; Baltatzis, George; Fonseca, Pedro; Rodriguez, Patricia; Gogvadze, Vladimir; Lennartsson, Lena; Björklund, Ann-Charlotte; Zhivotovsky, Boris; Grandér, Dan; Egevad, Lars; Nilsson, Sten; Panaretakis, Theocharis

    2015-01-01

    Autophagy is one of the main cytoprotective mechanisms that cancer cells deploy to withstand the cytotoxic stress and survive the lethal damage induced by anti-cancer drugs. However, under specific conditions, autophagy may, directly or indirectly, induce cell death. In our study, treatment of the Atg5-deficient DU145 prostate cancer cells, with the multi-tyrosine kinase inhibitor, sorafenib, induces mitochondrial damage, autophagy and cell death. Molecular inhibition of autophagy by silencing ULK1 and Beclin1 rescues DU145 cells from cell death indicating that, in this setting, autophagy promotes cell death. Re-expression of Atg5 restores the lipidation of LC3 and rescues DU145 and MEF atg5−/− cells from sorafenib-induced cell death. Despite the lack of Atg5 expression and LC3 lipidation, DU145 cells form autophagosomes as demonstrated by transmission and immuno-electron microscopy, and the formation of LC3 positive foci. However, the lack of cellular content in the autophagosomes, the accumulation of long-lived proteins, the presence of GFP-RFP-LC3 positive foci and the accumulated p62 protein levels indicate that these autophagosomes may not be fully functional. DU145 cells treated with sorafenib undergo a caspase-independent cell death that is inhibited by the RIPK1 inhibitor, necrostatin-1. Furthermore, treatment with sorafenib induces the interaction of RIPK1 with p62, as demonstrated by immunoprecipitation and a proximity ligation assay. Silencing of p62 decreases the RIPK1 protein levels and renders necrostatin-1 ineffective in blocking sorafenib-induced cell death. In summary, the formation of Atg5-deficient autophagosomes in response to sorafenib promotes the interaction of p62 with RIPK leading to cell death by necroptosis. PMID:26416459

  7. The Raf Kinase Inhibitor Sorafenib Inhibits JAK-STAT Signal Transduction in Human Immune Cells.

    PubMed

    Martin del Campo, Sara E; Levine, Kala M; Mundy-Bosse, Bethany L; Grignol, Valerie P; Fairchild, Ene T; Campbell, Amanda R; Trikha, Prashant; Mace, Thomas A; Paul, Bonnie K; Jaime-Ramirez, Alena Cristina; Markowitz, Joseph; Kondadasula, Sri Vidya; Guenterberg, Kristan D; McClory, Susan; Karpa, Volodymyr I; Pan, Xueliang; Olencki, Thomas E; Monk, J Paul; Mortazavi, Amir; Tridandapani, Susheela; Lesinski, Gregory B; Byrd, John C; Caligiuri, Michael A; Shah, Manisha H; Carson, William E

    2015-09-01

    Sorafenib is an oral multikinase inhibitor that was originally developed as a Raf kinase inhibitor. We hypothesized that sorafenib would also have inhibitory effects on cytokine signaling pathways in immune cells. PBMCs from normal donors were treated with varying concentrations of sorafenib and stimulated with IFN-α or IL-2. Phosphorylation of STAT1 and STAT5 was measured by flow cytometry and confirmed by immunoblot analysis. Changes in IFN-α- and IL-2-stimulated gene expression were measured by quantitative PCR, and changes in cytokine production were evaluated by ELISA. Cryopreserved PBMCs were obtained from cancer patients before and after receiving 400 mg sorafenib twice daily. Patient PBMCs were thawed, stimulated with IL-2 or IFN-α, and evaluated for phosphorylation of STAT1 and STAT5. Pretreatment of PBMCs with 10 μM sorafenib decreased STAT1 and STAT5 phosphorylation after treatment with IFN-α or IL-2. This inhibitory effect was observed in PBMCs from healthy donors over a range of concentrations of sorafenib (5-20 μM), IL-2 (2-24 nM), and IFN-α (10(1)-10(6) U/ml). This effect was observed in immune cell subsets, including T cells, B cells, NK cells, regulatory T cells, and myeloid-derived suppressor cells. Pretreatment with sorafenib also inhibited PBMC expression of IFN-α- and IL-2-regulated genes and inhibited NK cell production of IFN-γ, RANTES, MIP1-α, and MIG in response to IFN-α stimulation. PBMCs from patients receiving sorafenib therapy showed decreased responsiveness to IL-2 and IFN-α treatment. Sorafenib is a Raf kinase inhibitor that could have off-target effects on cytokine-induced signal transduction in immune effector cells. PMID:26238487

  8. Interstitial pneumonia induced by sorafenib in a patient with hepatocellular carcinoma: An autopsy case report

    PubMed Central

    YAMAGUCHI, TAKASHI; SEKI, TOSHIHITO; MIYASAKA, CHIKA; INOKUCHI, RYOSUKE; KAWAMURA, RINAKO; SAKAGUCHI, YUUTAKU; MURATA, MIKI; MATSUZAKI, KOICHI; NAKANO, YORIKA; UEMURA, YOSHIKO; OKAZAKI, KAZUICHI

    2015-01-01

    Sorafenib is a multikinase inhibitor currently approved in Japan for the treatment of unresectable hepatocellular carcinoma. Interstitial pneumonia induced by sorafenib may have a fatal outcome, and therefore, has recently been the focus of many studies. The current report presents an autopsy case of diffuse alveolar damage (DAD) that occurred in a 59-year-old male, who had been treated with sorafenib. The patient had been given sorafenib for six months and had exhibited no respiratory symptoms during this time. However, 19 days after sorafenib treatment was resumed, acute interstitial pneumonia developed. In previously reported cases, the first symptoms of pulmonary toxicity appeared following a limited treatment duration with sorafenib; this was in contrast to the patient in the current study, who developed the first symptoms after eight months. We therefore conclude that physicians must be aware of interstitial pneumonia as a potential pulmonary toxicity associated with sorafenib treatment when treatment with sorafenib is resumed, even after prolonged use. In addition, to best of our knowledge, this is the first case of a postmortem examination reported in patient with interstitial pneumonia induced by sorafenib treatment. PMID:25789013

  9. Sorafenib induces cell death in chronic lymphocytic leukemia by translational downregulation of Mcl-1.

    PubMed

    Huber, S; Oelsner, M; Decker, T; zum Büschenfelde, C Meyer; Wagner, M; Lutzny, G; Kuhnt, T; Schmidt, B; Oostendorp, R A J; Peschel, C; Ringshausen, I

    2011-05-01

    Chronic lymphocytic leukemia (CLL) has a high prevalence in western countries and remains incurable to date. Here, we provide evidence that the multikinase inhibitor sorafenib induces apoptosis in primary CLL cells. This strong pro-apoptotic effect is not restricted to any subgroup of patients, based on Binet stage and the expression of ZAP70 or CD38. Mechanistically, sorafenib-induced cell death is preceded by a rapid downregulation of Mcl-1 through the inhibition of protein translation. Subsequently, the cell intrinsic apoptotic pathway is activated, indicated by destabilization of the mitochondrial membrane potential and activation of caspase-3 and -9. In contrast to sorafenib, the monoclonal vascular epidermal growth factor (VEGF)-antibody bevacizumab failed to induce apoptosis in CLL cells, suggesting that sorafenib induces cell death irrespectively of VEGF signalling. Notably, although sorafenib inhibits phosphorylation of the Scr-kinase Lck, knock-down of Lck did not induce apoptosis in CLL cells. Of note, the pro-apoptotic effect of sorafenib is not restricted to cell-cycle arrested cells, but is also maintained in proliferating CLL cells. In addition, we provide evidence that sorafenib can overcome drug resistance in CLL cells protected by microenvironmental signals from stromal cells. Conclusively, sorafenib is highly active in CLL and may compose a new therapeutic option for patients who relapse after immunochemotherapy. PMID:21293487

  10. Sorafenib induces autophagic cell death and apoptosis in hepatic stellate cell through the JNK and Akt signaling pathways.

    PubMed

    Hao, Huiyao; Zhang, Di; Shi, Junli; Wang, Yan; Chen, Lei; Guo, Yongze; Ma, Junji; Jiang, Xiaoyu; Jiang, Huiqing

    2016-03-01

    Increasing hepatic stellate cell (HSC) death is an attractive approach for limiting liver fibrosis. We investigated the molecular mechanisms underlying the effects of sorafenib on HSCs. LX2 cells were incubated with sorafenib and a variety of inhibitors of apoptosis, autophagy, and necrosis. Electron microscopy was used to observe autophagosomes. Inhibitors and siRNA were used to examine the role of the Akt/mTOR/p70S6K and JNK pathways. Ultrastructural analysis revealed that rat HSCs treated with 5 μmol/l sorafenib accumulated residual digested material and empty or autophagic vacuoles. Incubating LX2 cells with lysosomal protease inhibitors increased the accumulation of LC3-II, indicating that sorafenib enhances autophagic flux in HSCs. Autophagy may precede apoptosis. Lower concentrations of sorafenib and a shorter treatment time resulted in the dominance of autophagic cell death over apoptosis. Further analysis showed that Beclin 1 is inactivated by the caspases induced by sorafenib during apoptosis. Inhibition of autophagy in LX2 cells using 3-methyladenine treatment or siRNA-mediated knockdown of Atg5 resulted in a marked increase in apoptosis. Finally, sorafenib induced programmed cell death by attenuation and activation of Akt/mTOR/p70S6K and JNK signaling. Sorafenib-induced cell death is mediated by both autophagy and apoptosis. Elucidation of the signaling pathways activated by sorafenib could potentially lead to novel antifibrosis therapies for chronic liver diseases. PMID:26629768

  11. Sorafenib induces apoptosis in HL60 cells by inhibiting Src kinase-mediated STAT3 phosphorylation.

    PubMed

    Zhao, Wei; Zhang, Tao; Qu, Bingqian; Wu, Xingxin; Zhu, Xu; Meng, Fanyu; Gu, Yanhong; Shu, Yongqian; Shen, Yan; Sun, Yang; Xu, Qiang

    2011-01-01

    Signal transducer and activator of transcription 3 (STAT3) is constitutively active in approximately 50% of acute myeloid leukemia (AML) cases and mediates multiple cellular processes including cell resistance to apoptosis. Inhibition of constitutively active STAT3 has been shown to induce AML cell apoptosis. Our aim was to ascertain if sorafenib, a multikinase inhibitor, may also inhibit STAT3 signaling and, therefore, be efficacious for AML. We found that sorafenib inhibited proliferation and induced apoptosis in human AML cell line (HL60) cells. In addition, sorafenib exposure reduced constitutive STAT3 phosphorylation in HL60 cells and repressed STAT3 DNA-binding activity and Mcl-1 and Bcl-2 expression. Similar results were obtained with the Src kinase inhibitor I, suggesting that sorafenib suppresses STAT3 phosphorylation by inhibiting Src-kinase activity. Furthermore, significant inhibition of Src kinase activity by sorafenib was observed in the kinase assay. In addition, Src could be co-immunoprecipitated with STAT3, and the phosphorylation of STAT3 was significantly inhibited by sorafenib only in cell lines in which phosphorylated Src is highly expressed. Taken together, our study indicates that sorafenib blocks Src kinase-mediated STAT3 phosphorylation and decreases the expression of apoptosis regulatory proteins Mcl-1 and Bcl-2, which are associated with increased apoptosis in HL60 cells. These findings provide a rationale for the treatment of human AML. PMID:20881478

  12. Sorafenib

    MedlinePlus

    ... of the body and cannot be treated with radioactive iodine. Sorafenib is in a class of medications ... as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this ...

  13. Effects of the multikinase inhibitors Sorafenib and Regorafenib in PTEN deficient neoplasias.

    PubMed

    Mirantes, Cristina; Dosil, Maria Alba; Eritja, Núria; Felip, Isidre; Gatius, Sònia; Santacana, Maria; Matias-Guiu, Xavier; Dolcet, Xavier

    2016-08-01

    The phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) axis is frequently dysregulated in cancer due to mutations in different nodes of the pathway or constitutive activation of receptor tyrosine kinases. Multikinase inhibitors as sorafenib and regorafenib represent a therapeutic approach for the treatment of these types of tumours. In the present study, we have evaluated the anti-tumoural effects of Sorafenib and Regorafenib on endometrial, prostate and thyroid neoplasias. Both inhibitors reduced cell viability in vitro and lead to a disruption of the PI3K/AKT/mTOR pathway. In vivo, we have demonstrated that Sorafenib and Regorafenib reduce thyroid hyperplasias induced by the loss of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), although none of the treatments eliminated the disease. Altogether, we present the first study that correlates the response to multikinase inhibitors with a specific mutation. Moreover, this is the first report characterising the response to Regorafenib in thyroid, prostate and endometrial neoplasias. PMID:27288872

  14. Successful treatment for sorafenib-induced liver dysfunction: a report of case with liver biopsy.

    PubMed

    Kuroda, Daisuke; Hayashi, Hiromitsu; Nitta, Hidetoshi; Imai, Katsunori; Abe, Shinya; Hashimoto, Daisuke; Chikamoto, Akira; Ishiko, Takatoshi; Beppu, Toru; Baba, Hideo

    2016-12-01

    Sorafenib is an oral multikinase inhibitor with anti-proliferative and anti-angiogenic effects and is used worldwide for the treatment of advanced or metastatic hepatocellular carcinoma (HCC). While the significant survival benefit of sorafenib in patients with advanced HCC was demonstrated, various treatment-related adverse events might happen. Of them, the incidence of drug-related severe liver dysfunction rarely occurs (<1 %) but is one of the serious adverse events by sorafenib. The authors highlight the case of a 71-year-old man with metastatic HCC with sorafenib-related fatal liver dysfunction (T-Bil 28.6 mg/dL, AST 1611 IU/L, ALT 1098 IU/L) 2 months later even without either intrahepatic viable HCC or hepatitis B virus (HBV) reactivation. Then, the liver dysfunction was improved following aggressive treatment using hyperbaric oxygen. A liver biopsy demonstrated cholestasis, degeneration, and necrosis in hepatocytes with lymphocyte infiltration. Thus, sorafenib rarely can induce liver dysfunction characterized by cholestatic and hepatocellular injury types, and it could be a fatal event. Clinicians should pay attention to any increase in the liver enzymes in these patients. PMID:26943680

  15. Inhibition of doxorubicin-induced autophagy in hepatocellular carcinoma Hep3B cells by sorafenib--the role of extracellular signal-regulated kinase counteraction.

    PubMed

    Manov, Irena; Pollak, Yulia; Broneshter, Rinata; Iancu, Theodore C

    2011-09-01

    A multikinase inhibitor of the Raf/mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) pathway, sorafenib, is increasingly being used in the management of hepatocellular carcinoma, and its combination with conventional chemotherapeutics has stimulated particular interest. Although the combination of sorafenib with doxorubicin (DOX) is presently being investigated in a phase III randomized trial, little is known about the molecular mechanisms of their interaction. Because DOX causes cell death through upregulation of the MEK/ERK pathway, and sorafenib has an opposite influence on the same cascade, we hypothesized that co-treatment with these drugs may lead to an antagonistic effect. DOX treatment arrested proliferation and induced autophagic cell death in Hep3B cells, whereas apoptotic changes were not conspicuous. Sorafenib alone affected viability and caused massive mitochondrial degradation. However, when added together with DOX, sorafenib facilitated cell cycle progression, increased survival, and reduced autophagy. To evaluate the molecular mechanisms of this phenomenon, we examined the expression of ERK1/2, protein kinase B (Akt), and cyclin D1, as well as the members of Bcl-2 family. ERK1/2 activation induced by DOX was suppressed by sorafenib. Similarly, ERK targeting with the selective inhibitor U0126 impaired DOX-induced toxicity. Treatment with sorafenib, either alone or in combination with DOX, resulted in Akt activation. The role of sorafenib-induced degradation of cyclin D1 in the suppression of DOX efficiency is discussed. In conclusion, MEK/ERK counteraction, stimulation of survival via Akt and dysregulation of cyclin D1 could contribute to the escape from DOX-induced autophagy and thus promote cancer cell survival. The use of MEK/ERK inhibitors in combination with chemotherapeutics, intended to enhance anticancer efficacy, requires the consideration of possible antagonistic effects. PMID:21790999

  16. Effect of CYP3A-inducing anti-epileptics on sorafenib exposure: results of a phase II study of sorafenib plus daily temozolomide in adults with recurrent glioblastoma

    PubMed Central

    Vredenburgh, James J.; Desjardins, Annick; Peters, Katherine; Gururangan, Sridharan; Sampson, John H.; Marcello, Jennifer; Herndon, James E.; McLendon, Roger E.; Janney, Dorothea; Friedman, Allan H.; Bigner, Darell D.; Friedman, Henry S.

    2011-01-01

    Sorafenib, an oral VEGFR-2, Raf, PDGFR, c-KIT and Flt-3 inhibitor, is active against renal cell and hepatocellular carcinomas, and has recently demonstrated promising activity for lung and breast cancers. In addition, various protracted temozolomide dosing schedules have been evaluated as a strategy to further enhance its anti-tumor activity. We reasoned that sorafenib and protracted, daily temozolomide may provide complementary therapeutic benefit, and therefore performed a phase 2 trial among recurrent glioblastoma patients. Adult glioblastoma patients at any recurrence after standard temozolomide chemoradiotherapy received sorafenib (400 mg twice daily) and continuous daily temozolomide (50 mg/m2/day). Assessments were performed every eight weeks. The primary endpoint was progression-free survival at 6 months (PFS-6) and secondary end points were radiographic response, overall survival (OS), safety and sorafenib pharmacokinetics. Of 32 enrolled patients, 12 (38%) were on CYP3-A inducing anti-epileptics (EIAEDs), 17 (53%) had 2 or more prior progressions, 15 had progressed while receiving 5-day temozolomide, and 12 (38%) had failed either prior bevacizumab or VEGFR inhibitor therapy. The most common grade ≥ 3 toxicities were palmer-planter erythrodysesthesia (19%) and elevated amylase/lipase (13%). Sorafenib pharmacokinetic exposures were comparable on day 1 regardless of EIAED status, but significantly lower on day 28 for patients on EIAEDs (P = 0.0431). With a median follow-up of 93 weeks, PFS-6 was 9.4%. Only one patient (3%) achieved a partial response. In conclusion, sorafenib can be safely administered with daily temozolomide, but this regimen has limited activity for recurrent GBM. Co-administration of EIAEDs can lower sorafenib exposures in this population. PMID:20443129

  17. Combination therapy for hepatocellular carcinoma: Additive preclinical efficacy of the HDAC inhibitor panobinostat with sorafenib

    PubMed Central

    Lachenmayer, Anja; Toffanin, Sara; Cabellos, Laia; Alsinet, Clara; Hoshida, Yujin; Villanueva, Augusto; Minguez, Beatriz; Tsai, Hung-Wen; Ward, Stephen C.; Thung, Swan; Friedman, Scott L.; Llovet, Josep M.

    2012-01-01

    Background & Aims Hepatocellular carcinoma (HCC) is a heterogeneous cancer in which sorafenib is the only approved systemic therapy. Histone deacetylases (HDAC) are commonly dysregulated in cancer and therefore represent promising targets for therapies, however their role in HCC pathogenesis is still unknown. We analyzed the expression of 11 HDACs in human HCCs and assessed the efficacy of the pan-HDAC inhibitor panobinostat alone and in combination with sorafenib in preclinical models of liver cancer. Methods Gene expression and copy number changes were analyzed in a cohort of 334 human HCCs, while the effects of panobinostat and sorafenib were evaluated in 3 liver cancer cell lines and a murine xenograft model. Results Aberrant HDAC expression was identified and validated in 91 and 243 HCCs, respectively. Upregulation of HDAC3 and 5 mRNAs were significantly correlated with DNA copy number gains. Inhibiting HDACs with panobinostat led to strong anti-tumoral effects in vitro and vivo, enhanced by the addition of sorafenib. Cell viability and proliferation declined, while apoptosis and autophagy increased. Panobinostat increased Histone H3 and HSP90 acetylation, downregulated BIRC5 (survivin) and upregulated CDH1. Combination therapy with panobinostat and sorafenib significantly decreased vessel density, and most significantly decreased tumor volume and increased survival in HCC xenografts. Conclusions Aberrant expression of several HDACs and copy number gains of HDAC3 and HDAC5 occur in HCC. Treatment with panobinostat combined with sorafenib demonstrated the highest preclinical efficacy in HCC models, providing the rationale for clinical studies with this novel combination. PMID:22322234

  18. Perifosine and sorafenib combination induces mitochondrial cell death and antitumor effects in NOD/SCID mice with Hodgkin lymphoma cell line xenografts.

    PubMed

    Locatelli, S L; Giacomini, A; Guidetti, A; Cleris, L; Mortarini, R; Anichini, A; Gianni, A M; Carlo-Stella, C

    2013-08-01

    The effects of the Akt inhibitor perifosine and the RAF/MEK/ERK inhibitor sorafenib were investigated using two CD30(+)Hodgkin lymphoma cell lines (L-540 and HDLM-2) and the CD30(-)HD-MyZ histiocytic cell line. The combined perifosine/sorafenib treatment significantly inhibited mitogen-activated protein kinase and Akt phosphorylation in two of the three cell lines. Profiling of the responsive cell lines revealed that perifosine/sorafenib decreased the amplitude of transcriptional signatures that are associated with the cell cycle, DNA replication and cell death. Tribbles homolog 3 (TRIB3) was identified as the main mediator of the in vitro and in vivo antitumor activity of perifosine/sorafenib. Combined treatment compared with single agents significantly suppressed cell growth (40-80%, P<0.001), induced severe mitochondrial dysfunction and necroptotic cell death (up to 70%, P<0.0001) in a synergistic manner. Furthermore, in vivo xenograft studies demonstrated a significant reduction in tumor burden (P<0.0001), an increased survival time (81 vs 45 days, P<0.0001), an increased apoptosis (2- to 2.5-fold, P<0.0001) and necrosis (2- to 8-fold, P<0.0001) in perifosine/sorafenib-treated animals compared with mice receiving single agents. These data provide a rationale for clinical trials using perifosine/sorafenib combination. PMID:23360848

  19. Sorafenib Enhances Radiation-Induced Apoptosis in Hepatocellular Carcinoma by Inhibiting STAT3

    SciTech Connect

    Huang, Chao-Yuan; Lin, Chen-Si; Tai, Wei-Tien; Hsieh, Chi-Ying; Shiau, Chung-Wai; Cheng, Ann-Lii; Chen, Kuen-Feng

    2013-07-01

    Purpose: Hepatocellular carcinoma (HCC) is one of the most common and lethal human malignancies. Lack of efficient therapy for advanced HCC is a pressing problem worldwide. This study aimed to determine the efficacy and mechanism of combined sorafenib and radiation therapy treatment for HCC. Methods and Materials: HCC cell lines (PLC5, Huh-7, Sk-Hep1, and Hep3B) were treated with sorafenib, radiation, or both, and apoptosis and signal transduction were analyzed. Results: All 4 HCC cell lines showed resistance to radiation-induced apoptosis; however, this resistance could be reversed in the presence of sorafenib. Inhibition of phospho-STAT3 was found in cells treated with sorafenib or sorafenib plus radiation and subsequently reduced the expression levels of STAT3-related proteins, Mcl-1, cyclin D1, and survivin. Silencing STAT3 by RNA interference overcame apoptotic resistance to radiation in HCC cells, and the ectopic expression of STAT3 in HCC cells abolished the radiosensitizing effect of sorafenib. Moreover, sorafenib plus radiation significantly suppressed PLC5 xenograft tumor growth. Conclusions: These results indicate that sorafenib sensitizes resistant HCC cells to radiation-induced apoptosis via downregulating phosphorylation of STAT3 in vitro and in vivo.

  20. Antitumor effect of the novel sphingosine kinase 2 inhibitor ABC294640 is enhanced by inhibition of autophagy and by sorafenib in human cholangiocarcinoma cells

    PubMed Central

    Ding, Xiwei; Chaiteerakij, Roongruedee; Moser, Catherine D.; Shaleh, Hassan; Boakye, Jeffrey; Chen, Gang; Ndzengue, Albert; Li, Ying; Zhou, Yanling; Huang, Shengbing; Sinicrope, Frank A.; Zou, Xiaoping; Thomas, Melanie B.; Smith, Charles D.; Roberts, Lewis R.

    2016-01-01

    Sphingosine kinase 2 (Sphk2) has an oncogenic role in cancer. A recently developed first-in-class Sphk2 specific inhibitor ABC294640 displays antitumor activity in many cancer models. However, the role of Sphk2 and the antitumor activity of its inhibitor ABC294640 are not known in cholangiocarcinoma. We investigated the potential of targeting Sphk2 for the treatment of cholangiocarcinoma. We found that Sphk2 is overexpressed in five established human cholangiocarcinoma cell lines (WITT, HuCCT1, EGI-1, OZ and HuH28) and a new patient-derived cholangiocarcinoma cell line (LIV27) compared to H69 normal cholangiocytes. Inhibition of Sphk2 by ABC294640 inhibited proliferation and induced caspase-dependent apoptosis. Furthermore, we found that ABC294640 inhibited STAT3 phosphorylation, one of the key signaling pathways regulating cholangiocarcinoma cell proliferation and survival. ABC294640 also induced autophagy. Inhibition of autophagy by bafilomycin A1 or chloroquine potentiated ABC294640-induced cytotoxicity and apoptosis. In addition, ABC294640 in combination with sorafenib synergistically inhibited cell proliferation of cholangiocarcinoma cells. Strong decreases in STAT3 phosphorylation were observed in WITT and HuCCT1 cells exposed to the ABC294640 and sorafenib combination. These findings provide novel evidence that Sphk2 may be a rational therapeutic target in cholangiocarcinoma. Combinations of ABC294640 with sorafenib and/or autophagy inhibitors may provide novel strategies for the treatment of cholangiocarcinoma. PMID:26956050

  1. Multikinase inhibitor sorafenib exerts cytocidal efficacy against Non-Hodgkin lymphomas associated with inhibition of MAPK14 and AKT phosphorylation.

    PubMed

    Chapuy, Bjoern; Schuelper, Nikolai; Panse, Melanie; Dohm, Andrea; Hand, Elisabeth; Schroers, Roland; Truemper, Lorenz; Wulf, Gerald G

    2011-02-01

    Intracellular signal transduction by kinase-mediated phosphorylation is essential for the survival and growth of lymphoma cells. This study analysed the multikinase inhibitor sorafenib for its cytotoxic activity against lymphoma cells. We found that sorafenib reduced cell viability at low micromolar concentrations in a time-dependent manner in cell lines and primary cell suspensions representing major types of aggressive B- and T-cell lymphomas. In cells surviving short term exposure, proliferative arrest occurred leading to complete loss of in vitro clonogenicity. Previously described sorafenib targets within the RAF kinase family were found to be expressed and phosphorylated in all cell lines, and sorafenib perturbed the activation of classical RAF/MEK/ERK pathway targets. However, using a global phoshoprotein array, the most consistent downstream effect of sorafenib in NHL cells was the inhibition of mitogen-activated protein kinase 14 (MAPK14) and panAKT phosphorylation. In conclusion, sorafenib has significant in vitro efficacy against aggressive B- and T-cell lymphoma cells, associated with inhibition of MAPK14 and panAKT. PMID:21689083

  2. Sorafenib-induced hepatocellular carcinoma cell death depends on reactive oxygen species production in vitro and in vivo.

    PubMed

    Coriat, Romain; Nicco, Carole; Chéreau, Christiane; Mir, Olivier; Alexandre, Jérôme; Ropert, Stanislas; Weill, Bernard; Chaussade, Stanislas; Goldwasser, François; Batteux, Frédéric

    2012-10-01

    Sorafenib is presently the only effective therapy in advanced hepatocellular carcinoma (HCC). Because most anticancer drugs act, at least in part, through the generation of reactive oxygen species, we investigated whether sorafenib can induce an oxidative stress. The effects of sorafenib on intracellular ROS production and cell death were assessed in vitro in human (HepG2) and murine (Hepa 1.6) HCC cell lines and human endothelial cells (HUVEC) as controls. In addition, 26 sera from HCC patients treated by sorafenib were analyzed for serum levels of advanced oxidation protein products (AOPP). Sorafenib significantly and dose-dependently enhanced in vitro ROS production by HCC cells. The SOD mimic MnTBAP decreased sorafenib-induced lysis of HepG2 cells by 20% and of Hepa 1.6 cells by 75% compared with HCC cells treated with 5 mg/L sorafenib alone. MnTBAP significantly enhanced by 25% tumor growth in mice treated by sorafenib. On the other hand, serum levels of AOPP were higher in HCC patients treated by sorafenib than in sera collected before treatment (P < 0.001). An increase in serum AOPP concentration ≥0.2 μmol/L chloramine T equivalent after 15 days of treatment is a predictive factor for sorafenib response with higher progression free survival (P < 0.05) and overall survival rates (P < 0.05). As a conclusion, sorafenib dose-dependently induces the generation of ROS in tumor cells in vitro and in vivo. The sera of Sorafenib-treated HCC patients contain increased AOPP levels that are correlated with the clinical effectiveness of sorafenib and can be used as a marker of effectiveness of the drug. . PMID:22902857

  3. SC-2001 Overcomes STAT3-mediated Sorafenib Resistance through RFX-1/SHP-1 Activation in Hepatocellular Carcinoma☆☆☆

    PubMed Central

    Su, Jung-Chen; Tseng, Ping-Hui; Wu, Szu-Hsien; Hsu, Cheng-Yi; Tai, Wei-Tien; Li, Yong-Shi; Chen, I-Ting; Liu, Chun-Yu; Chen, Kuen-Feng; Shiau, Chung-Wai

    2014-01-01

    Hepatocellular carcinoma is the fifth most common solid cancer worldwide. Sorafenib, a small multikinase inhibitor, is the only approved therapy for advanced HCC. The clinical benefit of sorafenib is offset by the acquisition of sorafenib resistance. Understanding of the molecular mechanism of STAT3 overexpression in sorafenib resistance is critical if the clinical benefits of this drug are to be improved. In this study, we explored our hypothesis that loss of RFX-1/SHP-1 and further increase of p-STAT3 as a result of sorafenib treatment induces sorafenib resistance as a cytoprotective response effect, thereby, limiting sorafenib sensitivity and efficiency. We found that knockdown of RFX-1 protected HCC cells against sorafenib-induced cell apoptosis and SHP-1 activity was required for the process. SC-2001, a molecule with similar structure to obatoclax, synergistically suppressed tumor growth when used in combination with sorafenib in vitro and overcame sorafenib resistance through up-regulating RFX-1 and SHP-1 resulting in tumor suppression and mediation of dephosphorylation of STAT3. In addition, sustained sorafenib treatment in HCC led to increased p-STAT3 which was a key mediator of sorafenib sensitivity. The combination of SC-2001 and sorafenib strongly inhibited tumor growth in both wild-type and sorafenib-resistant HCC cell bearing xenograft models. These results demonstrate that inactivation of RFX/SHP-1 induced by sustained sorafenib treatment confers sorafenib resistance to HCC through p-STAT3 up-regulation. These effects can be overcome by SC-2001 through RFX-1/SHP-1 dependent p-STAT3 suppression. In conclusion, the use of SC-2001 in combination with sorafenib may constitute a new strategy for HCC therapy. PMID:25047655

  4. Differential modulatory effects of GSK-3β and HDM2 on sorafenib-induced AIF nuclear translocation (programmed necrosis) in melanoma

    PubMed Central

    2011-01-01

    Background GSK-3β phosphorylates numerous substrates that govern cell survival. It phosphorylates p53, for example, and induces its nuclear export, HDM2-dependent ubiquitination, and proteasomal degradation. GSK-3β can either enhance or inhibit programmed cell death, depending on the nature of the pro-apoptotic stimulus. We previously showed that the multikinase inhibitor sorafenib activated GSK-3β and that this activation attenuated the cytotoxic effects of the drug in various BRAF-mutant melanoma cell lines. In this report, we describe the results of studies exploring the effects of GSK-3β on the cytotoxicity and antitumor activity of sorafenib combined with the HDM2 antagonist MI-319. Results MI-319 alone increased p53 levels and p53-dependent gene expression in melanoma cells but did not induce programmed cell death. Its cytotoxicity, however, was augmented in some melanoma cell lines by the addition of sorafenib. In responsive cell lines, the MI-319/sorafenib combination induced the disappearance of p53 from the nucleus, the down modulation of Bcl-2 and Bcl-xL, the translocation of p53 to the mitochondria and that of AIF to the nuclei. These events were all GSK-3β-dependent in that they were blocked with a GSK-3β shRNA and facilitated in otherwise unresponsive melanoma cell lines by the introduction of a constitutively active form of the kinase (GSK-3β-S9A). These modulatory effects of GSK-3β on the activities of the sorafenib/MI-319 combination were the exact reverse of its effects on the activities of sorafenib alone, which induced the down modulation of Bcl-2 and Bcl-xL and the nuclear translocation of AIF only in cells in which GSK-3β activity was either down modulated or constitutively low. In A375 xenografts, the antitumor effects of sorafenib and MI-319 were additive and associated with the down modulation of Bcl-2 and Bcl-xL, the nuclear translocation of AIF, and increased suppression of tumor angiogenesis. Conclusions Our data demonstrate a

  5. Biological evaluation of a novel sorafenib analogue, t-CUPM.

    PubMed

    Wecksler, Aaron T; Hwang, Sung Hee; Liu, Jun-Yan; Wettersten, Hiromi I; Morisseau, Christophe; Wu, Jian; Weiss, Robert H; Hammock, Bruce D

    2015-01-01

    Sorafenib (Nexavar®) is currently the only FDA-approved small molecule targeted therapy for advanced hepatocellular carcinoma. The use of structural analogues and derivatives of sorafenib has enabled the elucidation of critical targets and mechanism(s) of cell death for human cancer lines. We previously performed a structure-activity relationship study on a series of sorafenib analogues designed to investigate the inhibition overlap between the major targets of sorafenib Raf-1 kinase and VEGFR-2, and an enzyme shown to be a potent off-target of sorafenib, soluble epoxide hydrolase. In the current work, we present the biological data on our lead sorafenib analogue, t-CUPM, demonstrating that this analogue retains cytotoxicity similar to sorafenib in various human cancer cell lines and strongly inhibits growth in the NCI-60 cell line panel. Co-treatment with the pan-caspase inhibitor, Z-VAD-FMK, failed to rescue the cell viability responses of both sorafenib and t-CUPM, and immunofluorescence microscopy shows similar mitochondrial depolarization and apoptosis-inducing factor release for both compounds. These data suggest that both compounds induce a similar mechanism of caspase-independent apoptosis in hepatoma cells. In addition, t-CUPM displays anti-proliferative effects comparable to sorafenib as seen by a halt in G0/G1 in cell cycle progression. The structural difference between sorafenib and t-CUPM significantly reduces inhibitory spectrum of kinases by this analogue, and pharmacokinetic characterization demonstrates a 20-fold better oral bioavailability of t-CUPM than sorafenib in mice. Thus, t-CUPM may have the potential to reduce the adverse events observed from the multikinase inhibitory properties and the large dosing regimens of sorafenib. PMID:25413440

  6. The multikinase inhibitor Sorafenib enhances glycolysis and synergizes with glycolysis blockade for cancer cell killing

    PubMed Central

    Tesori, Valentina; Piscaglia, Anna Chiara; Samengo, Daniela; Barba, Marta; Bernardini, Camilla; Scatena, Roberto; Pontoglio, Alessandro; Castellini, Laura; Spelbrink, Johannes N.; Maulucci, Giuseppe; Puglisi, Maria Ausiliatrice; Pani, Giovambattista; Gasbarrini, Antonio

    2015-01-01

    Although the only effective drug against primary hepatocarcinoma, the multikinase inhibitor Sorafenib (SFB) usually fails to eradicate liver cancer. Since SFB targets mitochondria, cell metabolic reprogramming may underlie intrinsic tumor resistance. To characterize cancer cell metabolic response to SFB, we measured oxygen consumption, generation of reactive oxygen species (ROS) and ATP content in rat LCSC (Liver Cancer Stem Cells) -2 cells exposed to the drug. Genome wide analysis of gene expression was performed by Affymetrix technology. SFB cytotoxicity was evaluated by multiple assays in the presence or absence of metabolic inhibitors, or in cells genetically depleted of mitochondria. We found that low concentrations (2.5–5 μM) of SFB had a relatively modest effect on LCSC-2 or 293 T cell growth, but damaged mitochondria and increased intracellular ROS. Gene expression profiling of SFB-treated cells was consistent with a shift toward aerobic glycolysis and, accordingly, SFB cytotoxicity was dramatically increased by glucose withdrawal or the glycolytic inhibitor 2-DG. Under metabolic stress, activation of the AMP dependent Protein Kinase (AMPK), but not ROS blockade, protected cells from death. We conclude that mitochondrial damage and ROS drive cell killing by SFB, while glycolytic cell reprogramming may represent a resistance strategy potentially targetable by combination therapies. PMID:25779766

  7. A Dosing/Cross-Development Study of the Multikinase Inhibitor Sorafenib in Patients With Pulmonary Arterial Hypertension

    PubMed Central

    Gomberg-Maitland, M; Maitland, ML; Barst, RJ; Sugeng, L; Coslet, S; Perrino, TJ; Bond, L; LaCouture, ME; Archer, SL; Ratain, MJ

    2012-01-01

    Pulmonary arterial hypertension (PAH) and cancer share elements of pathophysiology. This provides an opportunity for the cross-development of anticancer agents that can be used in improving PAH care. The adaptation of new drugs across these disease populations warrants a structured approach. This study was a 16-week, phase Ib, single-center, open-label trial of the multikinase/angiogenesis inhibitor sorafenib. In order to assess the safety of sorafenib in PAH, patients with advanced but stable disease on parenteral prostanoids (with or without oral sildenafil) were initiated on treatment at the lowest active dosage administered to cancer patients: 200 mg daily. Patients underwent weekly clinical evaluations and monthly functional testing and dose escalations to a final dosage of 400 mg twice daily. Among 12 patients (10 of them women), sorafenib was well tolerated at 200 mg twice daily. The most common adverse events were moderate skin reactions on the hands and feet and alopecia. Our conclusion was therefore that this is a tolerable dosing regimen for testing the therapeutic activity of sorafenib in PAH patients. PMID:20010555

  8. Inhibition of Autophagy by Chloroquine Enhances the Antitumor Efficacy of Sorafenib in Glioblastoma.

    PubMed

    Liu, Xiangyu; Sun, Kangjian; Wang, Handong; Dai, Yuyuan

    2016-10-01

    Glioblastoma multiforme (GBM) is the most aggressive and common brain tumor in adults. Sorafenib, a multi-kinase inhibitor, has been shown to inhibit cell proliferation and induce apoptosis through inhibition of STAT3 signaling in glioblastoma cells and in intracranial gliomas. However, sorafenib also induces cell autophagy. Due to the dual roles of autophagy in tumor cell survival and death, the therapeutic effect of sorafenib on glioblastoma is uncertain. Here, we combined sorafenib treatment in GBM cells (U373 and LN229) and tumors with the autophagy inhibitor chloroquine. We found that blockage of autophagy further inhibited cell proliferation and migration and induced cell apoptosis in vitro and in vivo. These findings suggest the possibility of combination treatment with sorafenib and autophagy inhibitors for GBM. PMID:26971793

  9. Vitamin K enhancement of Sorafenib-mediated HCC cell growth inhibition in vitro and in vivo

    PubMed Central

    Wei, Gang; Wang, Meifanf; Hyslop, Terry; Wang, Ziqiu; Carr, Brian I.

    2010-01-01

    The multi-kinase inhibitor Sorafenib, is the first oral agent to show activity against human hepatocellular carcinoma (HCC). Apoptosis has been shown to be induced in HCC by several agents, including Sorafenib, as well as by the naturally occurring K vitamins (VKs). Since few non toxic agents have activity against HCC growth, we evaluated the activity of Sorafenib and K vitamins, both independently and together on the growth in vitro and in vivo of HCC cells. We found that when VK was combined with Sorafenib, the concentration of Sorafenib required for growth inhibition was substantially reduced. Conversely, VK enhanced Sorafenib effects in several HCC cell lines on growth inhibition. Growth could be inhibited at doses of VK plus Sorafenib that were ineffective with either agent alone,using vitamins K1, K2 and K5. Combination VK1 plus Sorafenib induced apoptosis on FACS, TUNEL staining and caspase activation. Phospho-ERK levels were decreased, as was Mcl-1, an ERK target. Sorafenib alone inhibited growth of transplantable HCC in vivo. At sub-effective Sorafenib doses in vivo, addition of VK1 caused major tumor regression, with decreased phospho-ERK and Mcl-1 staining. Thus, combination VK1 plus Sorafenib strongly induced growth inhibition and apoptosis in rodent and human HCC and inhibited the RAF/MEK/ERK pathway. VK1 alone activated PKA, a mediator of inhibitory Raf phosphorylation. Thus, each agent can antagonize Raf; Sorafenib as a direct inhibitor and VK1 through inhibitory Raf phosphorylation. Since both agents are available for human use, the combination has potential for improving Sorafenib effects in HCC. PMID:21351273

  10. Ambulatory monitoring detects sorafenib-induced blood pressure elevations on the first day of treatment

    PubMed Central

    Maitland, Michael L.; Kasza, Kristen E.; Karrison, Theodore; Moshier, Kristin; Sit, Laura; Black, Henry R.; Undevia, Samir D.; Stadler, Walter M.; Elliott, William J.; Ratain, Mark J.

    2009-01-01

    Purpose Hypertension is a mechanism-based toxicity of sorafenib and other cancer therapeutics that inhibit the vascular endothelial growth factor (VEGF) signaling pathway (VSP). This prospective, single center, cohort study characterized ambulatory blood pressure (BP) monitoring (ABPM) as an early pharmacodynamic biomarker of VSP inhibition by sorafenib. Experimental Design Fifty-four normotensive advanced cancer patients underwent 24-hour ABPM prior to and between days 6 and 10 of sorafenib therapy. After BP changes were detected among the first cohort within 10 days, ABPM was performed during the first 24 hours of treatment for the second cohort. Results For the entire patient population the BP increase (mean systolic +10.8 mmHg [95% CI, 8.6 to 13.0], range −5.2 to +28.7 mmHg; mean diastolic +8.0 mmHg [95% CI, 6.3 to 9.7], range −4.4 to +27.1mmHg) was detected between days 6 and 10 (P <0.0001 for both) and plateaued thereafter. Variability in BP change did not associate with: age, body size, sex, self-reported race, baseline BP, or steady state sorafenib plasma concentrations. In the second cohort the BP elevation was detected during the first 24 hours (mean systolic +8.2 mmHg [95% CI, 5.0 to 11.3]; mean diastolic +6.5 mmHg [95% CI, 4.7 to 8.3] P <0.0001 for both). Conclusions ABPM detects the BP response to VSP inhibition by sorafenib during the first 24 hours of treatment. The magnitude of BP elevation is highly variable and unpredictable, but could be important in optimizing the therapeutic index of VSP inhibitor therapy. PMID:19773379

  11. The Effect of Sorafenib, Tadalafil and Macitentan Treatments on Thyroxin-Induced Hemodynamic Changes and Cardiac Abnormalities

    PubMed Central

    Saad, Nancy S.; Floyd, Kyle; Ahmed, Amany A. E.; Mohler, Peter J.

    2016-01-01

    Multikinase inhibitors (e.g. Sorafenib), phosphodiesterase-5 inhibitors (e.g. Tadalafil), and endothelin-1 receptor blockers (e.g. Macitentan) exert influential protection in a variety of animal models of cardiomyopathy; however, their effects on thyroxin-induced cardiomyopathy have never been investigated. The goal of the present study was to assess the functional impact of these drugs on thyroxin-induced hemodynamic changes, cardiac hypertrophy and associated altered responses of the contractile myocardium both in-vivo at the whole heart level and ex-vivo at the cardiac tissue level. Control and thyroxin (500 μg/kg/day)-treated mice with or without 2-week treatments of sorafenib (10 mg/kg/day; I.P), tadalafil (1 mg/kg/day; I.P or 4 mg/kg/day; oral), macitentan (30 and 100 mg/kg/day; oral), and their vehicles were studied. Blood pressure, echocardiography and electrocardiogram were non-invasively evaluated, followed by ex-vivo assessments of isolated multicellular cardiac preparations. Thyroxin increased blood pressure, resulted in cardiac hypertrophy and left ventricular dysfunction in-vivo. Also, it caused contractile abnormalities in right ventricular papillary muscles ex-vivo. None of the drug treatments were able to significantly attenuate theses hemodynamic changes or cardiac abnormalities in thyroxin-treated mice. We show here for the first time that multikinase (raf1/b, VEGFR, PDGFR), phosphodiesterase-5, and endothelin-1 pathways have no major role in thyroxin-induced hemodynamic changes and cardiac abnormalities. In particular, our data show that the involvement of endothelin-1 pathway in thyroxine-induced cardiac hypertrophy/dysfunction seems to be model-dependent and should be carefully interpreted. PMID:27082116

  12. The Effect of Sorafenib, Tadalafil and Macitentan Treatments on Thyroxin-Induced Hemodynamic Changes and Cardiac Abnormalities.

    PubMed

    Saad, Nancy S; Floyd, Kyle; Ahmed, Amany A E; Mohler, Peter J; Janssen, Paul M L; Elnakish, Mohammad T

    2016-01-01

    Multikinase inhibitors (e.g. Sorafenib), phosphodiesterase-5 inhibitors (e.g. Tadalafil), and endothelin-1 receptor blockers (e.g. Macitentan) exert influential protection in a variety of animal models of cardiomyopathy; however, their effects on thyroxin-induced cardiomyopathy have never been investigated. The goal of the present study was to assess the functional impact of these drugs on thyroxin-induced hemodynamic changes, cardiac hypertrophy and associated altered responses of the contractile myocardium both in-vivo at the whole heart level and ex-vivo at the cardiac tissue level. Control and thyroxin (500 μg/kg/day)-treated mice with or without 2-week treatments of sorafenib (10 mg/kg/day; I.P), tadalafil (1 mg/kg/day; I.P or 4 mg/kg/day; oral), macitentan (30 and 100 mg/kg/day; oral), and their vehicles were studied. Blood pressure, echocardiography and electrocardiogram were non-invasively evaluated, followed by ex-vivo assessments of isolated multicellular cardiac preparations. Thyroxin increased blood pressure, resulted in cardiac hypertrophy and left ventricular dysfunction in-vivo. Also, it caused contractile abnormalities in right ventricular papillary muscles ex-vivo. None of the drug treatments were able to significantly attenuate theses hemodynamic changes or cardiac abnormalities in thyroxin-treated mice. We show here for the first time that multikinase (raf1/b, VEGFR, PDGFR), phosphodiesterase-5, and endothelin-1 pathways have no major role in thyroxin-induced hemodynamic changes and cardiac abnormalities. In particular, our data show that the involvement of endothelin-1 pathway in thyroxine-induced cardiac hypertrophy/dysfunction seems to be model-dependent and should be carefully interpreted. PMID:27082116

  13. Multikinase Inhibitors Induce Cutaneous Toxicity through OAT6-Mediated Uptake and MAP3K7-Driven Cell Death.

    PubMed

    Zimmerman, Eric I; Gibson, Alice A; Hu, Shuiying; Vasilyeva, Aksana; Orwick, Shelley J; Du, Guoqing; Mascara, Gerard P; Ong, Su Sien; Chen, Taosheng; Vogel, Peter; Inaba, Hiroto; Maitland, Michael L; Sparreboom, Alex; Baker, Sharyn D

    2016-01-01

    The use of multikinase inhibitors (MKI) in oncology, such as sorafenib, is associated with a cutaneous adverse event called hand-foot skin reaction (HFSR), in which sites of pressure or friction become inflamed and painful, thus significantly impacting quality of life. The pathogenesis of MKI-induced HFSR is unknown, and the only available treatment options involve dose reduction or discontinuation of therapy, which have negative effects on primary disease management. To investigate the underlying mechanisms by which sorafenib promotes keratinocyte cytotoxicity and subsequent HFSR induction, we performed a transporter-directed RNAi screen in human epidermal keratinocytes and identified SLC22A20 (OAT6) as an uptake carrier of sorafenib. Further investigations into the intracellular mechanism of sorafenib activity through in situ kinome profiling identified the mitogen-activated protein kinase MAP3K7 (TAK1) as a target of sorafenib that induces cell death. Finally, we demonstrate that sorafenib induced keratinocyte injury in vivo and that this effect could be reversed by cotreatment with the OAT6 inhibitor probenecid. Collectively, our findings reveal a novel pathway that regulates the entry of some MKIs into keratinocytes and explains the basis underlying sorafenib-induced skin toxicity, with important implications for the therapeutic management of HFSR. PMID:26677977

  14. Galectin-1 induces hepatocellular carcinoma EMT and sorafenib resistance by activating FAK/PI3K/AKT signaling

    PubMed Central

    Zhang, P-F; Li, K-S; Shen, Y-h; Gao, P-T; Dong, Z-R; Cai, J-B; Zhang, C; Huang, X-Y; Tian, M-X; Hu, Z-Q; Gao, D-M; Fan, J; Ke, A-W; Shi, G-M

    2016-01-01

    Galectin-1 (Gal-1) is involved in several pathological activities associated with tumor progression and chemoresistance, however, the role and molecular mechanism of Gal-1 activity in hepatocellular carcinoma (HCC) epithelial–mesenchymal transition (EMT) and sorafenib resistance remain enigmatic. In the present study, forced Gal-1 expression promoted HCC progression and sorafenib resistance. Gal-1 elevated αvβ3-integrin expression, leading to AKT activation. Moreover, Gal-1 overexpression induced HCC cell EMT via PI3K/AKT cascade activation. Clinically, our data revealed that Gal-1 overexpression is correlated with poor HCC survival outcomes and sorafenib response. These data suggest that Gal-1 may be a potential therapeutic target for HCC and a biomarker for predicting response to sorafenib treatment. PMID:27100895

  15. Galectin-1 induces hepatocellular carcinoma EMT and sorafenib resistance by activating FAK/PI3K/AKT signaling.

    PubMed

    Zhang, P-F; Li, K-S; Shen, Y-H; Gao, P-T; Dong, Z-R; Cai, J-B; Zhang, C; Huang, X-Y; Tian, M-X; Hu, Z-Q; Gao, D-M; Fan, J; Ke, A-W; Shi, G-M

    2016-01-01

    Galectin-1 (Gal-1) is involved in several pathological activities associated with tumor progression and chemoresistance, however, the role and molecular mechanism of Gal-1 activity in hepatocellular carcinoma (HCC) epithelial-mesenchymal transition (EMT) and sorafenib resistance remain enigmatic. In the present study, forced Gal-1 expression promoted HCC progression and sorafenib resistance. Gal-1 elevated αvβ3-integrin expression, leading to AKT activation. Moreover, Gal-1 overexpression induced HCC cell EMT via PI3K/AKT cascade activation. Clinically, our data revealed that Gal-1 overexpression is correlated with poor HCC survival outcomes and sorafenib response. These data suggest that Gal-1 may be a potential therapeutic target for HCC and a biomarker for predicting response to sorafenib treatment. PMID:27100895

  16. Comprehensive overview of the efficacy and safety of sorafenib in advanced or metastatic renal cell carcinoma after a first tyrosine kinase inhibitor.

    PubMed

    Afonso, F J; Anido, U; Fernández-Calvo, O; Vázquez-Estévez, S; León, L; Lázaro, M; Ramos, M; Antón-Aparicio, L

    2013-06-01

    We performed a literature search that shed light on the signaling pathways involved in the sorafenib activity as first- or subsequent-line treatment, taking into account its toxicity profile. Sorafenib appears to have better tolerability when compared with other agents in the same indication. Cross-resistance between tyrosine kinase inhibitors (TKIs) may be limited, even after failure with a previous VEGFR inhibitor, but the optimal sequence with TKIs remains to be determined. Randomized trials of second-line treatment options have showed either modest or no differences in terms of progression-free and overall survival (OS). Direct comparison between sorafenib and axitinib demonstrated differences in terms of PFS in favor of axitinib, but not in terms of OS as second-line treatment. In contrast, a phase III study showed a benefit in OS, favoring sorafenib when compared with temsirolimus. In conclusion, after using other VEGF inhibitor such as sunitinib, sorafenib is active and safe for the treatment of patients with advanced or metastatic RCC. PMID:23401018

  17. Activation of phosphatidylinositol 3-kinase/Akt signaling mediates sorafenib-induced invasion and metastasis in hepatocellular carcinoma.

    PubMed

    Wang, Haiyong; Xu, Litao; Zhu, Xiaoyan; Wang, Peng; Chi, Huiying; Meng, Zhiqiang

    2014-10-01

    Sorafenib, an antiangiogenic agent, can promote tumor invasion and metastasis. The phosphatidylinositol 3-kinase (PI3K)/Akt/Snail-dependent pathway plays an important role in tumor invasion and metastasis. Yet, little is known concerning the role of the PI3K/Akt/Snail-dependent pathway in sorafenib‑induced invasion and metastasis of hepatic carcinoma (HCC). A human HCC orthotopic xenograft model was established, and sorafenib (30 mg/kg/day) was administered orally. Tumor growth and intrahepatic metastasis were assessed, and immunohistochemistry was applied to analyze the activation of the PI3K/Akt/Snail-dependent pathway. HCC cell lines were treated with sorafenib (1, 5 and 10 µM), and proliferation, migration and invasion were assessed. Western blotting and real-time polymerase chain reaction (RT-PCR) were used to examine the related gene expression of epithelial-mesenchymal transition (EMT) markers and the PI3K/Akt/Snail-dependent pathway. Sorafenib inhibited tumor growth and promoted intrahepatic invasion and metastasis of the orthotopic tumors grown from SMMC7721-GFP cells in vivo. Additionally, sorafenib promoted EMT and invasion and metastasis of HCC cells in vitro. Importantly, sorafenib enhanced PI3K and Akt activation and upregulation of the expression of transcription factor Snail, a critical EMT mediator. The upregulation of transcription factor Snail expression by sorafenib may be related to activation of the PI3K/AKT signaling pathway. The PI3K/Akt/Snail-dependent pathway may mediate the pro-invasive and pro-metastatic effects of sorafenib on HCC by inducing EMT. PMID:25070581

  18. Valproic acid overcomes transforming growth factor-β-mediated sorafenib resistance in hepatocellular carcinoma

    PubMed Central

    Matsuda, Yasunobu; Wakai, Toshifumi; Kubota, Masayuki; Osawa, Mami; Hirose, Yuki; Sakata, Jun; Kobayashi, Takashi; Fujimaki, Shun; Takamura, Masaaki; Yamagiwa, Satoshi; Aoyagi, Yutaka

    2014-01-01

    Sorafenib is a multi-kinase inhibitor approved for hepatocellular carcinoma, but rarely causes tumor regression in patients with chronic liver diseases. To investigate whether growth factor-mediated signaling is involved in sorafenib resistance, HepG2 and PLC/PRF/5 hepatoma cells were exposed to epidermal growth factor (EGF), hepatocyte growth factor (HGF) or transforming growth factor-β (TGF-β) prior to treatment with sorafenib. Furthermore, to identify an effective combination treatment with sorafenib, growth factor-sensitized cells were treated with sorafenib alone or in combination with celecoxib, lovastatin or valproic acid (VPA). Trypan blue staining and Annexin V assays showed that the cytotoxic effect of sorafenib was inhibited by 15-54% in cells sensitized to TGF-β (P<0.05). Western blotting analysis showed that TGF-β significantly activated extracellular signal-regulated kinase (ERK)-mediated AKT signaling, and sorafenib failed to suppress both ERK and AKT in TGF-β-sensitized cells. The decreased anti-tumor effect of sorafenib was rescued by chemical inhibition of ERK and AKT. When TGF-β-sensitized cells were treated with sorafenib plus VPA, the levels of phosphorylated ERK and AKT were considerably suppressed and the numbers of dead cells were increased by 3.7-5.7-fold compared with those exposed to sorafenib alone (P<0.05). Moreover, low dose sorafenib-induced cell migration was effectively suppressed by combination treatment with sorafenib and VPA. Collectively, TGF-β/ERK/AKT signaling might play a critical role in sorafenib resistance in hepatoma cells, and combination treatment with VPA may be effective against this drug resistance. PMID:24817927

  19. Modulation of Autophagy by Sorafenib: Effects on Treatment Response.

    PubMed

    Prieto-Domínguez, Nestor; Ordóñez, Raquel; Fernández, Anna; García-Palomo, Andres; Muntané, Jordi; González-Gallego, Javier; Mauriz, José L

    2016-01-01

    The multikinase inhibitor sorafenib is, at present, the only drug approved for the treatment of hepatocellular carcinoma (HCC), one of the most lethal types of cancer worldwide. However, the increase in the number of sorafenib tumor resistant cells reduces efficiency. A better knowledge of the intracellular mechanism of the drug leading to reduced cell survival could help to improve the benefits of sorafenib therapy. Autophagy is a bulk cellular degradation process activated in a broad range of stress situations, which allows cells to degrade misfolded proteins or dysfunctional organelles. This cellular route can induce survival or death, depending on cell status and media signals. Sorafenib, alone or in combination with other drugs is able to induce autophagy, but cell response to the drug depends on the complex integrative crosstalk of different intracellular signals. In cancerous cells, autophagy can be regulated by different cellular pathways (Akt-related mammalian target of rapamycin (mTOR) inhibition, 5' AMP-activated protein kinase (AMPK) induction, dissociation of B-cell lymphoma 2 (Bcl-2) family proteins from Beclin-1), or effects of some miRNAs. Inhibition of mTOR signaling by sorafenib and diminished interaction between Beclin-1 and myeloid cell leukemia 1 (Mcl-1) have been related to induction of autophagy in HCC. Furthermore, changes in some miRNAs, such as miR-30α, are able to modulate autophagy and modify sensitivity in sorafenib-resistant cells. However, although AMPK phosphorylation by sorafenib seems to play a role in the antiproliferative action of the drug, it does not relate with modulation of autophagy. In this review, we present an updated overview of the effects of sorafenib on autophagy and its related activation pathways, analyzing in detail the involvement of autophagy on sorafenib sensitivity and resistance. PMID:27375485

  20. Modulation of Autophagy by Sorafenib: Effects on Treatment Response

    PubMed Central

    Prieto-Domínguez, Nestor; Ordóñez, Raquel; Fernández, Anna; García-Palomo, Andres; Muntané, Jordi; González-Gallego, Javier; Mauriz, José L.

    2016-01-01

    The multikinase inhibitor sorafenib is, at present, the only drug approved for the treatment of hepatocellular carcinoma (HCC), one of the most lethal types of cancer worldwide. However, the increase in the number of sorafenib tumor resistant cells reduces efficiency. A better knowledge of the intracellular mechanism of the drug leading to reduced cell survival could help to improve the benefits of sorafenib therapy. Autophagy is a bulk cellular degradation process activated in a broad range of stress situations, which allows cells to degrade misfolded proteins or dysfunctional organelles. This cellular route can induce survival or death, depending on cell status and media signals. Sorafenib, alone or in combination with other drugs is able to induce autophagy, but cell response to the drug depends on the complex integrative crosstalk of different intracellular signals. In cancerous cells, autophagy can be regulated by different cellular pathways (Akt-related mammalian target of rapamycin (mTOR) inhibition, 5′ AMP-activated protein kinase (AMPK) induction, dissociation of B-cell lymphoma 2 (Bcl-2) family proteins from Beclin-1), or effects of some miRNAs. Inhibition of mTOR signaling by sorafenib and diminished interaction between Beclin-1 and myeloid cell leukemia 1 (Mcl-1) have been related to induction of autophagy in HCC. Furthermore, changes in some miRNAs, such as miR-30α, are able to modulate autophagy and modify sensitivity in sorafenib-resistant cells. However, although AMPK phosphorylation by sorafenib seems to play a role in the antiproliferative action of the drug, it does not relate with modulation of autophagy. In this review, we present an updated overview of the effects of sorafenib on autophagy and its related activation pathways, analyzing in detail the involvement of autophagy on sorafenib sensitivity and resistance. PMID:27375485

  1. Paradoxical exacerbation of chronic plaque psoriasis by sorafenib.

    PubMed

    Yiu, Z Z N; Ali, F R; Griffiths, C E M

    2016-06-01

    Vascular endothelial growth factor (VEGF) antagonists have been investigated as a potential treatment for psoriasis, but there have been reports of VEGF antagonists triggering and/or exacerbating pre-existing psoriasis. We present the case of a 61-year old-man with exacerbation of pre-existing psoriasis after treatment with sorafenib, a small molecule inhibitor of the tyrosine kinase domain of the VEGF receptor, and we review the literature for other published cases of sorafenib-induced or sorafenib-exacerbated psoriasis. Clinicians, including both dermatologists and oncologists, should be aware of this potential side-effect of sorafenib in addition to the other cutaneous side effects reported for this drug. PMID:26667599

  2. Novel sorafenib analogues induce apoptosis through SHP-1 dependent STAT3 inactivation in human breast cancer cells

    PubMed Central

    2013-01-01

    Introduction Signal transducers and activators of transcription 3 (STAT3) signaling is constitutively activated in various cancers including breast cancer and has emerged as a novel potential anti-cancer target. STAT3 has been demonstrated to be a target of sorafenib, and a protein tyrosine phosphatase Src homology 2-domain containing tyrosine phosphatase 1 (SHP-1) has been demonstrated to downregulate p-STAT3 via its phosphatase activity. Here, we tested the efficacy of two sorafenib analogues, SC-1 and SC-43, in breast cancer cells and examined the drug mechanism. Methods Breast cancer cell lines were used for in vitro studies. Cell viability was examined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was examined by flow cytometry and western blot. Signal transduction pathways in cells were assessed by western blot. In vivo efficacy of sorafenib, SC-1 and SC-43 was tested in xenografted nude mice. Results SC-1 and SC-43 induced more potent apoptosis than sorafenib, in association with downregulation of p-STAT3 and its downstream proteins cyclin D1 and survivin in a dose-dependent manner in breast cancer cell lines (HCC-1937, MDA-MB-468, MDA-MB-231, MDA-MB-453, SK-BR3, MCF-7). Overexpression of STAT3 in MDA-MB-468 cells protected the cells from apoptosis induced by sorafenib, SC-1 and SC-43. Moreover, SC-1 and SC-43 upregulated SHP-1 activity to a greater extent than sorafenib as measured by in vitro phosphatase assays. Knockdown of SHP-1 by siRNA reduced apoptosis induced by SC-1 and SC-43. Importantly, SC-1 and SC-43 showed more efficacious antitumor activity and p-STAT3 downregulation than sorafenib in MDA-MB-468 xenograft tumors. Conclusions Novel sorafenib analogues SC-1 and SC-43 induce apoptosis through SHP-1 dependent STAT3 inactivation and demonstrate greater potency than sorafenib in human breast cancer cells. PMID:23938089

  3. Sorafenib suppresses the cell cycle and induces the apoptosis of hepatocellular carcinoma cell lines in serum-free media

    PubMed Central

    TOMIZAWA, MINORU; SHINOZAKI, FUMINOBU; SUGIYAMA, TAKAO; YAMAMOTO, SHIGENORI; SUEISHI, MAKOTO; YOSHIDA, TAKANOBU

    2010-01-01

    To suppress the invasion of hepatocellular carcinoma (HCC) cells into surrounding connective tissues during metastasis, we investigated the usefulness of sorafenib. In order to search for model cell lines, cell numbers were counted to reveal cell lines with the potential to proliferate in serum-free media. Cell proliferation and cell motility were analyzed with the MTS and wound assay, respectively. 5-Bromo-2′-deoxyuridine (BrdU) labeling and mitotic and apoptotic indices were analyzed to assess the cell cycle and apoptosis. The expression levels of cyclin D1 and the cleavage of caspase-3 were analyzed by Western blotting. HLF cells exhibited growth in the serum-free medium, while the other cell lines examined did not. Sorafenib suppressed the cell proliferation and motility of the HLF cells in the serum-free media. Both indices of BrdU and mitotic potential decreased and the apoptotic index was increased in the serum-free media with sorafenib, suggesting that the cell cycle was suppressed and apoptosis was induced. The expression levels of cyclin D1 decreased and the cleavage of caspase-3 was noted in the serum-free media with sorafenib. Sorafenib may be suitable for molecular therapy to suppress the metastasis of HCC. PMID:22993610

  4. Sorafenib suppresses JNK-dependent apoptosis through inhibition of ZAK.

    PubMed

    Vin, Harina; Ching, Grace; Ojeda, Sandra S; Adelmann, Charles H; Chitsazzadeh, Vida; Dwyer, David W; Ma, Haiching; Ehrenreiter, Karin; Baccarini, Manuela; Ruggieri, Rosamaria; Curry, Jonathan L; Ciurea, Ana M; Duvic, Madeleine; Busaidy, Naifa L; Tannir, Nizar M; Tsai, Kenneth Y

    2014-01-01

    Sorafenib is U.S. Food and Drug Adminstration-approved for the treatment of renal cell carcinoma and hepatocellular carcinoma and has been combined with numerous other targeted therapies and chemotherapies in the treatment of many cancers. Unfortunately, as with other RAF inhibitors, patients treated with sorafenib have a 5% to 10% rate of developing cutaneous squamous cell carcinoma (cSCC)/keratoacanthomas. Paradoxical activation of extracellular signal-regulated kinase (ERK) in BRAF wild-type cells has been implicated in RAF inhibitor-induced cSCC. Here, we report that sorafenib suppresses UV-induced apoptosis specifically by inhibiting c-jun-NH(2)-kinase (JNK) activation through the off-target inhibition of leucine zipper and sterile alpha motif-containing kinase (ZAK). Our results implicate suppression of JNK signaling, independent of the ERK pathway, as an additional mechanism of adverse effects of sorafenib. This has broad implications for combination therapies using sorafenib with other modalities that induce apoptosis. PMID:24170769

  5. Activation of AMP-activated protein kinase by retinoic acid sensitizes hepatocellular carcinoma cells to apoptosis induced by sorafenib

    PubMed Central

    Ishijima, Naoki; Kanki, Keita; Shimizu, Hiroki; Shiota, Goshi

    2015-01-01

    To improve the outcome of cancer chemotherapy, strategies to enhance the efficacy of anticancer drugs are required. Sorafenib is the only drug to prolong overall survival of the patients with hepatocellular carcinoma (HCC), however, the outcome is still not satisfactory. Retinoids, vitamin A derivatives, have been known to exhibit inhibitory effects on various cancers including HCC. In this study, we investigated the effects of combined treatment using sorafenib and retinoids including all-trans retinoic acid (ATRA), NIK-333, and Am80 on HCC cells. Cell viability assays in six HCC cell lines, HepG2, PLC/PRF/5, HuH6, HLE, HLF, and Hep3B, revealed that 5 and 10 μM ATRA, concentrations that do not exert cytotoxic effects, enhanced the cytotoxicity of sorafenib, being much more effective than NIK-333 and Am80. We found that ATRA induced AMP-activated protein kinase activation, which was followed by reduced intracellular ATP level. Gene expression analysis revealed that ATRA decreased the expression of glycolytic genes such as GLUT-1 and LDHA. In the combination treatment using ATRA and sorafenib, increased apoptosis, followed by the activation of p38 MAPK and JNK, the upregulation and translocation of Bax to mitochondria, and the activation of caspase-3, was observed. Suppression of AMP-activated protein kinase by siRNA restored the viability of the cells treated with ATRA and sorafenib. Our results thus indicate that ATRA is useful for enhancing the cytotoxicity of sorafenib against HCC cells by regulating the energy metabolism of HCC cells. PMID:25683251

  6. Activation of AMP-activated protein kinase by retinoic acid sensitizes hepatocellular carcinoma cells to apoptosis induced by sorafenib.

    PubMed

    Ishijima, Naoki; Kanki, Keita; Shimizu, Hiroki; Shiota, Goshi

    2015-05-01

    To improve the outcome of cancer chemotherapy, strategies to enhance the efficacy of anticancer drugs are required. Sorafenib is the only drug to prolong overall survival of the patients with hepatocellular carcinoma (HCC), however, the outcome is still not satisfactory. Retinoids, vitamin A derivatives, have been known to exhibit inhibitory effects on various cancers including HCC. In this study, we investigated the effects of combined treatment using sorafenib and retinoids including all-trans retinoic acid (ATRA), NIK-333, and Am80 on HCC cells. Cell viability assays in six HCC cell lines, HepG2, PLC/PRF/5, HuH6, HLE, HLF, and Hep3B, revealed that 5 and 10 μM ATRA, concentrations that do not exert cytotoxic effects, enhanced the cytotoxicity of sorafenib, being much more effective than NIK-333 and Am80. We found that ATRA induced AMP-activated protein kinase activation, which was followed by reduced intracellular ATP level. Gene expression analysis revealed that ATRA decreased the expression of glycolytic genes such as GLUT-1 and LDHA. In the combination treatment using ATRA and sorafenib, increased apoptosis, followed by the activation of p38 MAPK and JNK, the upregulation and translocation of Bax to mitochondria, and the activation of caspase-3, was observed. Suppression of AMP-activated protein kinase by siRNA restored the viability of the cells treated with ATRA and sorafenib. Our results thus indicate that ATRA is useful for enhancing the cytotoxicity of sorafenib against HCC cells by regulating the energy metabolism of HCC cells. PMID:25683251

  7. [A case of advanced hepatocellular carcinoma successfully treated by liver resection after complete response induced by sorafenib administration].

    PubMed

    Kim, Yongkook; Hosoda, Yohei; Kakita, Naruyasu; Yamada, Yukinori; Yamasaki, Masaru; Nishino, Masaya; Okano, Miho; Nagai, Kenichi; Yasui, Masayoshi; Tsujinaka, Toshimasa

    2014-11-01

    A 50-year-old man presented to our hospital with the chief complaint of right hypochondriac pain and a palpable tumor. Advanced hepatocellular carcinoma (HCC) and chronic hepatitis B infection were diagnosed and treated by twice-repeated transcatheterarterial chemoembolization (TACE) followed by administration of entecavir. Two months after the last TACE, alpha-fetoprotein(AFP)and protein induced by vitamin K absence or antagonistII (PIVKA-II) levels had elevated, and multiple small early enhancing nodules were detected on computed tomography(CT)scan. Based on his age and liver function (Child-Pugh score A5), a full dose of sorafenib (800 mg/day) was administered. The sorafenib dose was decreased after one month to 400mg/day because of hand-foot syndrome. Following sorafenib administration, the lesions shrank markedly, and complete response (CR) according to modified Response Evaluation Criteria In Solid Tumors(mRECIST)was achieved within 4 months. Six months after sorafenib treatment was begun, recurrent HCC was detected in segment 6, near the previously treated lesion. The decreased size of the main tumor and normalization of AFP levels allowed curative surgical resection. The patient was discharged 5 days after surgery and is currently treated with a half dose of sorafenib. Thirteen months after surgery, a small early enhancing lesion is visible on postoperative CT scan, but AFP and PIVKA-II levels are still keeping in a normal range. This case demonstrates that if sorafenib treatment is effective, then subsequent surgical treatment can be reconsidered in patients with advanced HCC responding to this combined therapy. PMID:25731444

  8. Sneddon-Wilkinson disease induced by sorafenib in a patient with advanced hepatocellular carcinoma.

    PubMed

    Tajiri, Kazuto; Nakajima, Takahiko; Kawai, Kengo; Minemura, Masami; Sugiyama, Toshiro

    2015-01-01

    Sorafenib is the standard treatment for patients with advanced hepatocellular carcinoma (HCC), although it is known to cause a variety of dermatologic adverse events. Subcorneal pustular dermatosis (SCPD), also known as Sneddon-Wilkinson disease, is a rare skin eruption that accompanies various systemic disorders and may become chronically progressive. We herein describe the case of a patient who developed SCPD after sorafenib administration. The dermatologic reaction was improved by the cessation of sorafenib and worsened by its readministration. Clinicians treating HCC patients with sorafenib should be aware of the possibility of SCPD. PMID:25786448

  9. Association of toxicity of sorafenib and sunitinib for human keratinocytes with inhibition of signal transduction and activator of transcription 3 (STAT3).

    PubMed

    Yamamoto, Kazuhiro; Mizumoto, Atsushi; Nishimura, Kohji; Uda, Atsushi; Mukai, Akira; Yamashita, Kazuhiko; Kume, Manabu; Makimoto, Hiroo; Bito, Toshinori; Nishigori, Chikako; Nakagawa, Tsutomu; Hirano, Takeshi; Hirai, Midori

    2014-01-01

    Hand-foot skin reaction is a most common multi-kinase inhibitor-related adverse event. This study aimed to examine whether the toxicity of sorafenib and sunitinib for human keratinocytes was associated with inhibiting signal transduction and activator of transcription 3 (STAT3). We studied whether STAT3 activity affects sorafenib- and sunitinib-induced cell growth inhibition in HaCaT cells by WST-8 assay. Stattic enhanced the cell-growth inhibitory and apoptotic effects of sorafenib and sunitinib. HaCaT cells transfected with constitutively-active STAT3 (STAT3C) were resistant to the sorafenib- and sunitinib-induced cell growth inhibition. STAT3 activity decreased after short-term treatment with sorafenib and sunitinib in a dose-dependent manner and recovered after long-term treatment with sorafenib and sunitinib at low doses. Moreover, the expression of survivin and bcl-2 decreased after treatment with sorafenib and sunitinib was concomitant with variations in STAT3 activity. Sorafenib-induced STAT3 inhibition was mediated by regulation via MAPK pathways in HaCaT cells, while sunitinib-induced STAT3 inhibition was not. Thus, STAT3 activation mediating apoptosis suppressors may be a key factor in sorafenib and sunitinib-induced keratinocyte cytotoxicity. PMID:25013907

  10. MicroRNA-122 confers sorafenib resistance to hepatocellular carcinoma cells by targeting IGF-1R to regulate RAS/RAF/ERK signaling pathways.

    PubMed

    Xu, Yanmin; Huang, Ji; Ma, Leina; Shan, Juanjuan; Shen, Junjie; Yang, Zhi; Liu, Limei; Luo, Yongli; Yao, Chao; Qian, Cheng

    2016-02-28

    Sorafenib is the first-line treatment for advanced hepatocellular carcinoma (HCC), but the clinical response to sorafenib is seriously limited by drug resistance. In this study, we investigated the molecular mechanisms of sorafenib resistance in HCC cells. Our miRNA microarray data indicate that liver-specific miR-122 expression was significantly reduced in sorafenib-resistant cells. Overexpression of miR-122 made drug-tolerant cells sensitive to sorafenib and induced apoptosis. Insulin-like growth factor 1 receptor (IGF-1R) was validated as a target of miR-122 and was repressed by this miRNA. miR-122-induced apoptosis was repressed by the IGF-1R activator IGFI or IGFII. Conversely, the IGF-1R inhibitor PPP or NVP-AEW541 in combination with sorafenib significantly induced cell apoptosis and disrupted tolerance to drugs in vitro. These results indicated that activation of IGF-1R by ectopic down-regulation of miR-122 counteracted the effects of sorafenib-induced apoptosis, thus conferring sorafenib resistance. Further study revealed that activation of IGF-1R by miR-122 down-regulation contributed to activation of RAS/RAF/ERK signaling, which was associated with drug resistance. Our data imply that an intimate correlation between miR-122 and IGF-1R abnormal expression is a critical determinant of sorafenib tolerance. PMID:26655273

  11. NMR-Based Metabolic Profiling Reveals Neurochemical Alterations in the Brain of Rats Treated with Sorafenib.

    PubMed

    Du, Changman; Shao, Xue; Zhu, Ruiming; Li, Yan; Zhao, Qian; Fu, Dengqi; Gu, Hui; Kong, Jueying; Luo, Li; Long, Hailei; Deng, Pengchi; Wang, Huijuan; Hu, Chunyan; Zhao, Yinglan; Cen, Xiaobo

    2015-11-01

    Sorafenib, an active multi-kinase inhibitor, has been widely used as a chemotherapy drug to treat advanced clear-cell renal cell carcinoma patients. In spite of the relative safety, sorafenib has been shown to exert a negative impact on cognitive functioning in cancer patients, specifically on learning and memory; however, the underlying mechanism remains unclear. In this study, an NMR-based metabolomics approach was applied to investigate the neurochemical effects of sorafenib in rats. Male rats were once daily administrated with 120 mg/kg sorafenib by gavage for 3, 7, and 28 days, respectively. NMR-based metabolomics coupled with histopathology examinations for hippocampus, prefrontal cortex (PFC), and striatum were performed. The (1)H NMR spectra data were analyzed by using multivariate pattern recognition techniques to show the time-dependent biochemical variations induced by sorafenib. Excellent separation was obtained and distinguishing metabolites were observed between sorafenib-treated and control rats. A total of 36 differential metabolites in hippocampus of rats treated with sorafenib were identified, some of which were significantly changed. Furthermore, these modified metabolites mainly reflected the disturbances in neurotransmitters, energy metabolism, membrane, and amino acids. However, only a few metabolites in PFC and striatum were altered by sorafenib. Additionally, no apparent histological changes in these three brain regions were observed in sorafenib-treated rats. Together, our findings demonstrate the disturbed metabonomics pathways, especially, in hippocampus, which may underlie the sorafenib-induced cognitive deficits in patients. This work also shows the advantage of NMR-based metabolomics over traditional approach on the study of biochemical effects of drugs. PMID:26233726

  12. The ruthenium compound KP1339 potentiates the anticancer activity of sorafenib in vitro and in vivo☆

    PubMed Central

    Heffeter, Petra; Atil, Bihter; Kryeziu, Kushtrim; Groza, Diana; Koellensperger, Gunda; Körner, Wilfried; Jungwirth, Ute; Mohr, Thomas; Keppler, Bernhard K.; Berger, Walter

    2013-01-01

    KP1339 is a promising ruthenium-based anticancer compound in early clinical development. This study aimed to test the effects of KP1339 on the in vitro and in vivo activity of the multi-kinase inhibitor sorafenib, the current standard first-line therapy for advanced hepatoma. Anticancer activity of the parental compounds as compared to the drug combination was tested against a panel of cancer cell lines with a focus on hepatoma. Combination of KP1339 with sorafenib induced in the majority of all cases distinctly synergistic effects, comprising both sorafenib-resistant as well as sorafenib-responsive cell models. Several mechanisms were found to underlie these multifaceted synergistic activities. Firstly, co-exposure induced significantly enhanced accumulation levels of both drugs resulting in enhanced apoptosis induction. Secondly, sorafenib blocked KP1339-mediated activation of P38 signalling representing a protective response against the ruthenium drug. In addition, sorafenib treatment also abrogated KP1339-induced G2/M arrest but resulted in check point-independent DNA-synthesis block and a complete loss of the mitotic cell populations. The activity of the KP1339/sorafenib combination was evaluated in the Hep3B hepatoma xenograft. KP1339 monotherapy led to a 2.4-fold increase in life span and, thus, was superior to sorafenib, which induced a 1.9-fold prolonged survival. The combined therapy further enhanced the mean survival by 3.9-fold. Synergistic activity was also observed in the VM-1 melanoma xenograft harbouring an activating braf mutation. Together, our data indicate that the combination of KP1339 with sorafenib displays promising activity in vitro and in vivo especially against human hepatoma models. PMID:23790465

  13. CXCR4-targeted lipid-coated PLGA nanoparticles deliver sorafenib and overcome acquired drug resistance in liver cancer.

    PubMed

    Gao, Dong-Yu; Lin, Ts-Ting; Sung, Yun-Chieh; Liu, Ya Chi; Chiang, Wen-Hsuan; Chang, Chih-Chun; Liu, Jia-Yu; Chen, Yunching

    2015-10-01

    Sorafenib, a multikinase inhibitor, has been used as an anti-angiogenic agent against highly vascular hepatocellular carcinoma (HCC) - yet associated with only moderate therapeutic effect and the high incidence of HCC recurrence. We have shown intratumoral hypoxia induced by sorafenib activated C-X-C receptor type 4 (CXCR4)/stromal-derived factor 1α (SDF1α) axis, resulting in polarization toward a tumor-promoting microenvironment and resistance to anti-angiogenic therapy in HCC. Herein, we formulated sorafenib in CXCR4-targeted lipid-coated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) modified with a CXCR4 antagonist, AMD3100 to systemically deliver sorafenib into HCC and sensitize HCC to sorafenib treatment. We demonstrated that CXCR4-targeted NPs efficiently delivered sorafenib into HCCs and human umbilical vein endothelial cells (HUVECs) to achieve cytotoxicity and anti-angiogenic effect in vitro and in vivo. Despite the increased expression of SDF1α upon the persistent hypoxia induced by sorafenib-loaded CXCR4-targeted NPs, AMD3100 attached to the NPs can block CXCR4/SDF1α, leading to the reduced infiltration of tumor-associated macrophages, enhanced anti-angiogenic effect, a delay in tumor progression and increased overall survival in the orthotopic HCC model compared with other control groups. In conclusion, our results highlight the clinical potential of CXCR4-targeted NPs for delivering sorafenib and overcoming acquired drug resistance in liver cancer. PMID:26218745

  14. Early Sorafenib-Induced Toxicity Is Associated with Drug Exposure and UGTIA9 Genetic Polymorphism in Patients with Solid Tumors: A Preliminary Study

    PubMed Central

    Golmard, Jean Louis; Thomas-Schoemann, Audrey; Mir, Olivier; Taieb, Fabrice; Durand, Jean-Philippe; Coriat, Romain; Dauphin, Alain; Vidal, Michel; Tod, Michel; Loriot, Marie-Anne; Goldwasser, François; Blanchet, Benoit

    2012-01-01

    Background Identifying predictive biomarkers of drug response is of key importance to improve therapy management and drug selection in cancer therapy. To date, the influence of drug exposure and pharmacogenetic variants on sorafenib-induced toxicity remains poorly documented. The aim of this pharmacokinetic/pharmacodynamic (PK/PD) study was to investigate the relationship between early toxicity and drug exposure or pharmacogenetic variants in unselected adult outpatients treated with single-agent sorafenib for advanced solid tumors. Methods Toxicity was recorded in 54 patients on days 15 and 30 after treatment initiation and sorafenib exposure was assessed in 51 patients. The influence of polymorphisms in CYP3A5, UGT1A9, ABCB1 and ABCG2 was examined in relation to sorafenib exposure and toxicity. Clinical characteristics, drug exposure and pharmacogenetic variants were tested univariately for association with toxicities. Candidate variables with p<0.1 were analyzed in a multivariate analysis. Results Gender was the sole parameter independently associated with sorafenib exposure (p = 0.0008). Multivariate analysis showed that increased cumulated sorafenib (AUCcum) was independently associated with any grade ≥3 toxicity (p = 0.037); UGT1A9 polymorphism (rs17868320) with grade ≥2 diarrhea (p = 0.015) and female gender with grade ≥2 hand-foot skin reaction (p = 0.018). Using ROC curve, the threshold AUCcum value of 3,161 mg/L.h was associated with the highest risk to develop any grade ≥3 toxicity (p = 0.018). Conclusion In this preliminary study, increased cumulated drug exposure and UGT1A9 polymorphism (rs17868320) identified patients at high risk for early sorafenib-induced severe toxicity. Further PK/PD studies on larger population are warranted to confirm these preliminary results. PMID:22912756

  15. Low-dose taxotere enhances the ability of sorafenib to induce apoptosis in gastric cancer models.

    PubMed

    Tesei, Anna; Leonetti, Carlo; Zupi, Gabriella; Scarsella, Marco; Brigliadori, Giovanni; Ulivi, Paola; Fabbri, Francesco; Arienti, Chiara; Amadori, Dino; Passardi, Alessandro; Silvestrini, Rosella; Zoli, Wainer

    2011-02-01

    Despite the low efficacy of conventional antitumour drugs, chemotherapy remains an essential tool in controlling advanced gastric and oesophageal cancers. We aimed to provide a biological rationale based on the sorafenib-taxotere interaction for the clinical treatment of gastric cancer. In vitro experiments were performed on four human gastric cancer cell lines (GK2, AKG, KKP and NCI-N87). Cytotoxicity was evaluated by sulforhodamine B (SRB) assay, cell cycle perturbations, apoptosis and mitotic catastrophe were assessed by flow cytometric and microscopic analyses, and protein expression was studied by Western blot. In the in vivo experiments, nude mice xenografted with the most resistant line were treated with sorafenib and docetaxel singly or in association. Sorafenib inhibited cell growth (IG(50) values ranged from 3.4 to 8.1 μM) and caused down-regulation of MAP-K/ERK phosphorylation and of mcl-1 and p-bad expression after a 48-hr exposure. Apoptosis induction was associated with caspase-3 and -9 activation and mitochondrial membrane depolarization. The drug combination enhanced apoptosis (up to 80%) and produced a synergistic interaction when low doses of the taxane preceded administration of the antityrosine kinase. This synergism was probably due to the induction of an anomalous multidiploid G0-G1 peak and to consequent mitotic catastrophe, which increased sensitivity to sorafenib. Consistent with in vitro results, the docetaxel-sorafenib sequence exhibited high therapeutic efficacy in NCI-N87 mouse xenografts producing tumour weight inhibition (> 65%), tumour growth delay (up to 25 days) and increased mouse survival (30%). Our findings suggest the potential clinical usefulness of treatment with sorafenib and docetaxel for advanced gastric cancer. PMID:20015197

  16. Elevated hepatocyte growth factor expression as an autocrine c-Met activation mechanism in acquired resistance to sorafenib in hepatocellular carcinoma cells.

    PubMed

    Firtina Karagonlar, Zeynep; Koc, Dogukan; Iscan, Evin; Erdal, Esra; Atabey, Neşe

    2016-04-01

    Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer and the third leading cause of cancer-related deaths worldwide. Limitations in HCC treatment result due to poor prognosis and resistance against traditional radiotherapy and chemotherapies. The multikinase inhibitor sorafenib is the only FDA approved drug available for advanced HCC patients, and development of second-line treatment options for patients who cannot tolerate or develop resistance to sorafenib is an urgent medical need. In this study, we established sorafenib-resistant cells from Huh7 and Mahlavu cell lines by long-term sorafenib exposure. Sorafenib-resistant HCC cells acquired spindle-shape morphology, upregulated mesenchymal markers, and showed significant increase in both migration and invasion abilities compared to their parental counterparts. Moreover, after long-term sorafenib treatment, HCC cells showed induction of hepatocyte growth factor (HGF) synthesis and secretion along with increased levels of c-Met kinase and its active phosphorylated form, indicating autocrine activation of HGF/c-Met signaling. Importantly, the combined treatment of the resistant cells with c-Met kinase inhibitor SU11274 and HGF neutralizing antibody significantly reversed the increased invasion ability of the cells. The combined treatment also significantly augmented sorafenib-induced apoptosis, suggesting restoration of sorafenib sensitivity. These results describe, for the first time, compensatory upregulation of HGF synthesis leading to autocrine activation of HGF/c-Met signaling as a novel cellular strategy in the acquisition of sorafenib resistance. Therefore, we suggest that combinatorial therapeutic strategies with HGF and c-Met inhibitors comprise promising candidates for overcoming sorafenib resistance. PMID:26790028

  17. Sorafenib inhibits tumor growth and vascularization of rhabdomyosarcoma cells by blocking IGF-1R-mediated signaling

    PubMed Central

    Maruwge, Wessen; D’Arcy, Pádraig; Folin, Annika; Brnjic, Slavica; Wejde, Johan; Davis, Anthony; Erlandsson, Fredrik; Bergh, Jonas; Brodin, Bertha

    2008-01-01

    The growth of many soft tissue sarcomas is dependent on aberrant growth factor signaling, which promotes their proliferation and motility. With this in mind, we evaluated the effect of sorafenib, a receptor tyrosine kinase inhibitor, on cell growth and apoptosis in sarcoma cell lines of various histological subtypes. We found that sorafenib effectively inhibited cell proliferation in rhabdomyosarcoma, synovial sarcoma and Ewing’s sarcoma with IC50 values <5 μM. Sorafenib effectively induced growth arrest in rhabdomyosarcoma cells, which was concurrent with inhibition of Akt and Erk signaling. Studies of ligand-induced phosphorylation of Erk and Akt in rhabdomyosarcoma cells showed that insulin-like growth factor-1 is a potent activator, which can be blocked by treatment with sorafenib. In vivo sorafenib treatment of rhabdomyosarcoma xenografts had a significant inhibitory effect on tumor growth, which was associated with inhibited vascularization and enhanced necrosis in the adjacent tumor stroma. Our results demonstrate that in vitro and in vivo growth of rhabdomyosarcoma can be suppressed by treatment with sorafenib, and suggests the possibilities of using sorafenib as a potential adjuvant therapy for the treatment of rhabdomyosarcoma. PMID:21127754

  18. Convection-enhanced delivery of sorafenib and suppression of tumor progression in a murine model of brain melanoma through the inhibition of signal transducer and activator of transcription 3.

    PubMed

    Zou, Zhaoxia; Yin, Yufang; Lin, Jenny; Hsu, Li-Chen J; Brandon, Vanessa L; Yang, Fan; Jove, Richard; Jandial, Rahul; Li, Gang; Chen, Mike Y

    2016-05-01

    OBJECT Despite recent advances, metastatic melanoma remains a terminal disease, in which life-threatening brain metastasis occurs in approximately half of patients. Sorafenib is a multikinase inhibitor that induces apoptosis of melanoma cells in vitro. However, systemic administration has been ineffective because adequate tissue concentrations cannot be achieved. This study investigated if convection-enhanced delivery (CED) of sorafenib would enhance tumor control and survival via inhibition of the signal transducer and activator of transcription 3 (Stat3) pathway in a murine model of metastatic brain melanoma. METHODS Melanoma cells treated with sorafenib in vitro were examined for signaling and survival changes. The effect of sorafenib given by CED was assessed by bioluminescent imaging and animal survival. RESULTS The results showed that sorafenib induced cell death in the 4 established melanoma cell lines and in 1 primary cultured melanoma cell line. Sorafenib inhibited Stat3 phosphorylation in HTB65, WYC1, and B16 cells. Accordingly, sorafenib treatment also decreased expression of Mcl-1 mRNA in melanoma cell lines. Because sorafenib targets multiple pathways, the present study demonstrated the contribution of the Stat3 pathway by showing that mouse embryonic fibroblast (MEF) Stat3 +/+ cells were significantly more sensitive to sorafenib than MEF Stat3 -/- cells. In the murine model of melanoma brain metastasis used in this study, CED of sorafenib increased survival by 150% in the treatment group compared with animals receiving the vehicle control (p < 0.01). CED of sorafenib also significantly abrogated tumor growth. CONCLUSIONS The data from this study indicate that local delivery of sorafenib effectively controls brain melanoma. These findings validate further investigation of the use of CED to distribute molecularly targeted agents. PMID:26544779

  19. Analysis of Imatinib and Sorafenib Binding to p38 Compared with c-Abl and b-Raf Provides Structural Insights for Understanding the Selectivity of Inhibitors Targeting the DFG-Out Form of Protein Kinases

    SciTech Connect

    Namboodiri, H.; Bukhtiyarova, M; Ramcharan, J; Karpusas, M; Lee, Y; Springman, E

    2010-01-01

    Protein kinases c-Abl, b-Raf, and p38{alpha} are recognized as important targets for therapeutic intervention. c-Abl and b-Raf are major targets of marketed oncology drugs Imatinib (Gleevec) and Sorafenib (Nexavar), respectively, and BIRB-796 is a p38{alpha} inhibitor that reached Phase II clinical trials. A shared feature of these drugs is the fact that they bind to the DFG-out forms of their kinase targets. Although the discovery of this class of kinase inhibitors has increased the level of emphasis on the design of DFG-out inhibitors, the structural determinants for their binding and stabilization of the DFG-out conformation remain unclear. To improve our understanding of these determinants, we determined cocrystal structures of Imatinib and Sorafenib with p38{alpha}. We also conducted a detailed analysis of Imatinib and Sorafenib binding to p38{alpha} in comparison with BIRB-796, including binding kinetics, binding interactions, the solvent accessible surface area (SASA) of the ligands, and stabilization of key structural elements of the protein upon ligand binding. Our results yield an improved understanding of the structural requirements for stabilizing the DFG-out form and a rationale for understanding the genesis of ligand selectivity among DFG-out inhibitors of protein kinases.

  20. Rapid long-lasting biochemical and radiological response to sorafenib in a case of advanced hepatocellular carcinoma.

    PubMed

    Gerardi, Assunta Maria Teresa; Stoppino, Luca Pio; Liso, Arcangelo; Macarini, Luca; Landriscina, Matteo

    2013-03-01

    The multikinase inhibitor sorafenib has demonstrated an overall survival benefit in phase III hepatocellular carcinoma (HCC) trials and has become the new standard of care for advanced stages of this disease. However, in clinical practice, the vast majority of patients obtain disease stabilization and occasionally tumor shrinkage. Furthermore, the appropriate timing of sorafenib therapy initiation, in order to maximize its clinical activity, remains under debate. We report a case of 4-year sorafenib treatment in a patient with an advanced hepatitis C virus (HCV)-related HCC with extensive infiltration of the inferior vena cava. Sorafenib treatment induced a rapid complete biochemical response and a long-term favorable outcome. Additionally, no major toxicities or detrimental effects on quality of life were observed. Thus, it is likely that a subgroup of human HCC may be highly sensitive to sorafenib; new molecular determinants are required to select those patients who may benefit from this therapy. Furthermore, a prompt initiation of treatment when the hepatic function is not compromised is a prerequisite for maximizing the clinical activity of sorafenib. PMID:23426789

  1. Rapid long-lasting biochemical and radiological response to sorafenib in a case of advanced hepatocellular carcinoma

    PubMed Central

    GERARDI, ASSUNTA MARIA TERESA; STOPPINO, LUCA PIO; LISO, ARCANGELO; MACARINI, LUCA; LANDRISCINA, MATTEO

    2013-01-01

    The multikinase inhibitor sorafenib has demonstrated an overall survival benefit in phase III hepatocellular carcinoma (HCC) trials and has become the new standard of care for advanced stages of this disease. However, in clinical practice, the vast majority of patients obtain disease stabilization and occasionally tumor shrinkage. Furthermore, the appropriate timing of sorafenib therapy initiation, in order to maximize its clinical activity, remains under debate. We report a case of 4-year sorafenib treatment in a patient with an advanced hepatitis C virus (HCV)-related HCC with extensive infiltration of the inferior vena cava. Sorafenib treatment induced a rapid complete biochemical response and a long-term favorable outcome. Additionally, no major toxicities or detrimental effects on quality of life were observed. Thus, it is likely that a subgroup of human HCC may be highly sensitive to sorafenib; new molecular determinants are required to select those patients who may benefit from this therapy. Furthermore, a prompt initiation of treatment when the hepatic function is not compromised is a prerequisite for maximizing the clinical activity of sorafenib. PMID:23426789

  2. Sorafenib inhibits lymphoma xenografts by targeting MAPK/ERK and AKT pathways in tumor and vascular cells.

    PubMed

    Carlo-Stella, Carmelo; Locatelli, Silvia L; Giacomini, Arianna; Cleris, Loredana; Saba, Elena; Righi, Marco; Guidetti, Anna; Gianni, Alessandro M

    2013-01-01

    The anti-lymphoma activity and mechanism(s) of action of the multikinase inhibitor sorafenib were investigated using a panel of lymphoma cell lines, including SU-DHL-4V, Granta-519, HD-MyZ, and KMS-11 cell lines. In vitro, sorafenib significantly decreased cell proliferation and phosphorylation levels of MAPK and PI3K/Akt pathways while increased apoptotic cell death. In vivo, sorafenib treatment resulted in a cytostatic rather than cytotoxic effect on tumor cell growth associated with a limited inhibition of tumor volumes. However, sorafenib induced an average 50% reduction of tumor vessel density and a 2-fold increase of necrotic areas. Upon sorafenib treatment, endothelial and tumor cells from SU-DHL-4V, Granta-519, and KMS-11 nodules showed a potent inhibition of either phospho-ERK or phospho-AKT, whereas a concomitant inhibition of phospho-ERK and phospho-AKT was only observed in HD-MyZ nodules. In conclusion, sorafenib affects the growth of lymphoid cell lines by triggering antiangiogenic mechanism(s) and directly targeting tumor cells. PMID:23620775

  3. Sorafenib Inhibits Lymphoma Xenografts by Targeting MAPK/ERK and AKT Pathways in Tumor and Vascular Cells

    PubMed Central

    Carlo-Stella, Carmelo; Locatelli, Silvia L.; Giacomini, Arianna; Cleris, Loredana; Saba, Elena; Righi, Marco; Guidetti, Anna; Gianni, Alessandro M.

    2013-01-01

    The anti-lymphoma activity and mechanism(s) of action of the multikinase inhibitor sorafenib were investigated using a panel of lymphoma cell lines, including SU-DHL-4V, Granta-519, HD-MyZ, and KMS-11 cell lines. In vitro, sorafenib significantly decreased cell proliferation and phosphorylation levels of MAPK and PI3K/Akt pathways while increased apoptotic cell death. In vivo, sorafenib treatment resulted in a cytostatic rather than cytotoxic effect on tumor cell growth associated with a limited inhibition of tumor volumes. However, sorafenib induced an average 50% reduction of tumor vessel density and a 2-fold increase of necrotic areas. Upon sorafenib treatment, endothelial and tumor cells from SU-DHL-4V, Granta-519, and KMS-11 nodules showed a potent inhibition of either phospho-ERK or phospho-AKT, whereas a concomitant inhibition of phospho-ERK and phospho-AKT was only observed in HD-MyZ nodules. In conclusion, sorafenib affects the growth of lymphoid cell lines by triggering antiangiogenic mechanism(s) and directly targeting tumor cells. PMID:23620775

  4. Chemotherapy for advanced hepatocellular carcinoma in the sorafenib age

    PubMed Central

    Miyahara, Koji; Nouso, Kazuhiro; Yamamoto, Kazuhide

    2014-01-01

    The kinase inhibitor sorafenib is the only systemic therapy proven to have a positive effect on survival of patients with advanced hepatocellular carcinoma (HCC). After development of sorafenib and its introduction as a therapeutic agent used in the clinic, several critical questions have been raised. Clinical parameters and biomarkers predicting sorafenib efficacy are the most important issues that need to be elucidated. Although it is difficult to know the responders in advance using conventional characteristics of patients, there are specific serum cytokines and/or gene amplification in tumor tissues that have been reported to predict efficacy of sorafenib. Risk and benefits of continuation of sorafenib beyond radiological progression is another issue to consider because no other standard therapy for advanced HCC as yet exists. In addition, effectiveness of the expanded application of sorafenib is still controversial, although a few studies have shed some light on combinational treatment with sorafenib for intermediate-stage HCC. Recently, over 50 relevant drugs have been developed and are currently under investigation. The efficacy of some of these drugs has been extensively examined, but none have demonstrated any superiority over sorafenib, so far. However, there are several drugs that have shown efficacy for treatment after sorafenib failure, and these are proceeding to further studies. To address these issues and questions, we have done extensive literature review and summarize the most current status of therapeutic application of sorafenib. PMID:24764653

  5. Targeting glucosylceramide synthase upregulation reverts sorafenib resistance in experimental hepatocellular carcinoma.

    PubMed

    Stefanovic, Milica; Tutusaus, Anna; Martinez-Nieto, Guillermo A; Bárcena, Cristina; de Gregorio, Estefania; Moutinho, Catia; Barbero-Camps, Elisabet; Villanueva, Alberto; Colell, Anna; Marí, Montserrat; García-Ruiz, Carmen; Fernandez-Checa, Jose C; Morales, Albert

    2016-02-16

    Evasive mechanisms triggered by the tyrosine kinase inhibitor sorafenib reduce its efficacy in hepatocellular carcinoma (HCC) treatment. Drug-resistant cancer cells frequently exhibit sphingolipid dysregulation, reducing chemotherapeutic cytotoxicity via the induction of ceramide-degrading enzymes. However, the role of ceramide in sorafenib therapy and resistance in HCC has not been clearly established. Our data reveals that ceramide-modifying enzymes, particularly glucosylceramide synthase (GCS), are upregulated during sorafenib treatment in hepatoma cells (HepG2 and Hep3B), and more importantly, in sorafenib-resistant cell lines. GCS silencing or pharmacological GCS inhibition sensitized hepatoma cells to sorafenib exposure. GCS inhibition, combined with sorafenib, triggered cytochrome c release and ATP depletion in sorafenib-treated hepatoma cells, leading to mitochondrial cell death after energetic collapse. Conversely, genetic GCS overexpression increased sorafenib resistance. Of interest, GCS inhibition improved sorafenib effectiveness in a xenograft mouse model, recovering drug sensitivity of sorafenib-resistant tumors in mice. In conclusion, our results reveal GCS induction as a mechanism of sorafenib resistance, suggesting that GCS targeting may be a novel strategy to increase sorafenib efficacy in HCC management, and point to target the mitochondria as the subcellular location where sorafenib therapy could be potentiated. PMID:26811497

  6. Quantification of Sorafenib in Human Serum by Competitive Enzyme-Linked Immunosorbent Assay.

    PubMed

    Saita, Tetsuya; Yamamoto, Yuta; Noda, Satoshi; Shioya, Makoto; Hira, Daiki; Andoh, Akira; Morita, Shin-Ya; Terada, Tomohiro; Shin, Masashi

    2015-01-01

    The multikinase inhibitor sorafenib has been used in the treatment of hepatocellular carcinoma, renal cell carcinoma, and differentiated thyroid carcinoma. Here we have demonstrated the production of the first specific antibody against sorafenib. Anti-sorafenib serum was obtained by immunizing mice with an antigen conjugated with bovine serum albumin and carboxylic modified 4-(4-aminophenoxy)-N-methyl-2-pyridinecarboxamide (AMPC) using the N-succinimidyl ester method. Enzyme labeling of sorafenib with horseradish peroxidase was similarly performed using carboxylic modified AMPC. A simple competitive enzyme-linked immunosorbent assay (ELISA) for sorafenib was developed using the principle of direct competition between sorafenib and the enzyme marker for anti-sorafenib antibody, which had been adsorbed by the plastic surface of a microtiter plate. Serum sorafenib concentrations lower than 0.04 µg/mL were reproducibly measurable using the ELISA. This ELISA was specific to sorafenib and showed very slight cross-reactivity (2.5%) with a major metabolite, sorafenib N-oxide. The values of serum sorafenib levels from 32 patients measured by this ELISA were comparable with those measured by HPLC, and there was a strong correlation between the values determined by the two methods (Y=1.016X-0.137, r=0.979). The specificity and sensitivity of the ELISA for sorafenib should provide a valuable new tool for use in therapeutic drug monitoring and pharmacokinetic studies of sorafenib. PMID:26521829

  7. Targeting glucosylceramide synthase upregulation reverts sorafenib resistance in experimental hepatocellular carcinoma

    PubMed Central

    Stefanovic, Milica; Tutusaus, Anna; Martinez-Nieto, Guillermo A.; Bárcena, Cristina; de Gregorio, Estefania; Moutinho, Catia; Barbero-Camps, Elisabet; Villanueva, Alberto; Colell, Anna; Marí, Montserrat; García-Ruiz, Carmen; Fernandez-Checa, Jose C.; Morales, Albert

    2016-01-01

    Evasive mechanisms triggered by the tyrosine kinase inhibitor sorafenib reduce its efficacy in hepatocellular carcinoma (HCC) treatment. Drug-resistant cancer cells frequently exhibit sphingolipid dysregulation, reducing chemotherapeutic cytotoxicity via the induction of ceramide-degrading enzymes. However, the role of ceramide in sorafenib therapy and resistance in HCC has not been clearly established. Our data reveals that ceramide-modifying enzymes, particularly glucosylceramide synthase (GCS), are upregulated during sorafenib treatment in hepatoma cells (HepG2 and Hep3B), and more importantly, in sorafenib-resistant cell lines. GCS silencing or pharmacological GCS inhibition sensitized hepatoma cells to sorafenib exposure. GCS inhibition, combined with sorafenib, triggered cytochrome c release and ATP depletion in sorafenib-treated hepatoma cells, leading to mitochondrial cell death after energetic collapse. Conversely, genetic GCS overexpression increased sorafenib resistance. Of interest, GCS inhibition improved sorafenib effectiveness in a xenograft mouse model, recovering drug sensitivity of sorafenib-resistant tumors in mice. In conclusion, our results reveal GCS induction as a mechanism of sorafenib resistance, suggesting that GCS targeting may be a novel strategy to increase sorafenib efficacy in HCC management, and point to target the mitochondria as the subcellular location where sorafenib therapy could be potentiated. PMID:26811497

  8. Potential molecular, cellular and microenvironmental mechanism of sorafenib resistance in hepatocellular carcinoma.

    PubMed

    Chen, Jiang; Jin, Renan; Zhao, Jie; Liu, Jinghua; Ying, Hanning; Yan, Han; Zhou, Senjun; Liang, Yuelong; Huang, Diyu; Liang, Xiao; Yu, Hong; Lin, Hui; Cai, Xiujun

    2015-10-10

    Sorafenib, an orally-available kinase inhibitor, is the only standard clinical treatment against advanced hepatocellular carcinoma. However, development of resistance to sorafenib has raised concern in recent years due to the high-level heterogeneity of individual response to sorafenib treatment. The resistance mechanism underlying the impaired sensitivity to sorafenib is still elusive though some researchers have made great efforts. Here, we provide a systemic insight into the potential molecular, cellular and microenvironmental mechanism of sorafenib resistance in hepatocellular carcinoma depending on abundant previous studies and reports. PMID:26170167

  9. Complete remission of advanced hepatocellular carcinoma by radiofrequency ablation after sorafenib therapy

    PubMed Central

    Park, Jung Gil; Park, Soo Young; Lee, Hye Won

    2015-01-01

    Sorafenib, a potent multikinase inhibitor, lead to a significant improvement in progression free survival and overall survival in patients with advanced hepatocellular carcinoma (HCC). Though sorafenib has proven its efficacy in advanced stage HCC, there are limited reports on the role of sorafenib allowing for curative treatment by down-staging. We herein report a case of advanced HCC with vascular invasion, which showed treatment response by sorafenib therapy as to allow for radiofrequency ablation as curative treatment. The patient was followed-up for 6 mo without recurrence with continued sorafenib therapy. PMID:25741170

  10. Iron depletion enhances the effect of sorafenib in hepatocarcinoma.

    PubMed

    Urano, Shinichi; Ohara, Toshiaki; Noma, Kazuhiro; Katsube, Ryoichi; Ninomiya, Takayuki; Tomono, Yasuko; Tazawa, Hiroshi; Kagawa, Shunsuke; Shirakawa, Yasuhiro; Kimura, Fumiaki; Nouso, Kazuhiro; Matsukawa, Akihiro; Yamamoto, Kazuhide; Fujiwara, Toshiyoshi

    2016-06-01

    ABSTACT Human hepatocellular carcinoma (HCC) is known to have a poor prognosis. Sorafenib, a molecular targeted drug, is most commonly used for HCC treatment. However, its effect on HCC is limited in clinical use and therefore new strategies regarding sorafenib treatment are required. Iron overload is known to be associated with progression of chronic hepatitis and increased risk of HCC. We previously reported that iron depletion inhibited cancer cell proliferation and conversely induced angiogenesis. Indeed iron depletion therapy including iron chelator needs to be combined with anti-angiogenic drug for its anti-cancer effect. Since sorafenib has an anti-angiogenic effect by its inhibitory targeting VEGFR, we hypothesized that sorafenib could complement the anti-cancer effect of iron depletion. We retrospectively analyzed the relationship between the efficacy of sorafenib and serum iron-related markers in clinical HCC patients. In clinical cases, overall survival was prolonged in total iron binding capacity (TIBC) high- and ferritin low-patients. This result suggested that the low iron-pooled patients, who could have a potential of more angiogenic properties in/around HCC tumors, could be adequate for sorafenib treatment. We determined the effect of sorafenib (Nexavar®) and/or deferasirox (EXJADE®) on cancer cell viability, and on cell signaling of human hepatocarcinoma HepG2 and HLE cells. Both iron depletion by deferasirox and sorafenib revealed insufficient cytotoxic effect by each monotherapy, however, on the basis of increased angiogenesis by iron depletion, the addition of deferasirox enhanced anti-proliferative effect of sorafenib. Deferasirox was confirmed to increase vascular endothelial growth factor (VEGF) secretion into cellular supernatants by ELISA analysis. In in vivo study sorafenib combined with deferasirox also enhanced sorafenib-induced apoptosis. These results suggested that sorafenib combined with deferasirox could be a novel combination

  11. Sorafenib enhances the therapeutic efficacy of rapamycin in colorectal cancers harboring oncogenic KRAS and PIK3CA

    PubMed Central

    Evers, B. Mark

    2012-01-01

    Activation of phosphatidylinositol 3-kinase (PI3K)/Akt signaling is associated with tumorigenesis and metastasis of colorectal cancer (CRC). The mammalian target of rapamycin (mTOR) kinase, a downstream effector of PI3K/Akt signaling, regulates tumorigenesis and metastasis of CRCs, indicating that mTOR inhibition may have therapeutic potential. Notwithstanding, many cancers, including CRC, demonstrate resistance to the antitumorigenic effects of rapamycin. In this study, we show that inhibition of mTORC1 with rapamycin leads to feedback activation of PI3K/Akt and Ras-MAPK signaling, resulting in cell survival and possible contribution to rapamycin resistance. Combination with the multikinase inhibitor, sorafenib, abrogates rapamycin-induced activation of PI3K/Akt and Ras-MAPK signaling pathways. Combination of rapamycin with sorafenib synergistically inhibits proliferation of CRC cells. CRCs harboring coexistent KRAS and PIK3CA mutations are partially sensitive to either rapamycin or sorafenib monotherapy, but highly sensitive to combination treatment with rapamycin and sorafenib. Combination with sorafenib enhances therapeutic efficacy of rapamycin on induction of apoptosis and inhibition of cell-cycle progression, migration and invasion of CRCs. We demonstrate efficacy and safety of concomitant treatment with rapamycin and sorafenib at inhibiting growth of xenografts from CRC cells with coexistent mutations in KRAS and PIK3CA. The efficacy and tolerability of combined treatment with rapamycin and sorafenib provides rationale for use in treating CRC patients, particularly those with tumors harboring coexistent KRAS and PIK3CA mutations. Abbreviations:CIcombination indexCRCcolorectal cancerIHCimmunohistochemistryMAPKmitogen activated protein kinasemTORmammalian target of rapamycinPI3Kphosphatidylinositol 3-kinase. PMID:22696593

  12. HDAC6-mediated EGFR stabilization and activation restrict cell response to sorafenib in non-small cell lung cancer cells.

    PubMed

    Wang, Zhihao; Hu, Pengchao; Tang, Fang; Xie, Conghua

    2016-05-01

    Sorafenib is a multi-targeted kinase inhibitor and has been the subject of extensive clinical research in advanced non-small cell lung cancer (NSCLC). However, sorafenib fails to improve overall survival of patients with advanced NSCLC. The molecular mechanisms that account for this phenomenon are unclear. Here we show that sorafenib treatment stabilizes epidermal growth factor receptor (EGFR) and activates EGFR pathway. Moreover, this is partly mediated by stabilization of histone deacetylase 6 (HDAC6), which has been shown to regulate EGFR endocytic trafficking and degradation. Overexpression of HDAC6 confers resistance to sorafenib in NSCLC cells. Inhibition of HDAC6 with selective inhibitors synergizes with sorafenib to kill NSCLC cells via inhibition of sorafenib-mediated EGFR pathway activation. Taken together, our findings might partly explain the failure of Phase III trial of sorafenib in improving overall survival of advanced NSCLC patients and bear possible implications for the improvement on the efficacy of sorafenib in treatment of NSCLC. PMID:27090797

  13. Fisetin, a phytochemical, potentiates sorafenib-induced apoptosis and abrogates tumor growth in athymic nude mice implanted with BRAF-mutated melanoma cells

    PubMed Central

    Pal, Harish Chandra; Baxter, Ronald D.; Hunt, Katherine M.; Agarwal, Jyoti; Elmets, Craig A.; Athar, Mohammad; Afaq, Farrukh

    2015-01-01

    Melanoma is the most deadly form of cutaneous malignancy, and its incidence rates are rising worldwide. In melanoma, constitutive activation of the BRAF/MEK/ERK (MAPK) and PI3K/AKT/mTOR (PI3K) signaling pathways plays a pivotal role in cell proliferation, survival and tumorigenesis. A combination of compounds that lead to an optimal blockade of these critical signaling pathways may provide an effective strategy for prevention and treatment of melanoma. The phytochemical fisetin is known to possess anti-proliferative and pro-apoptotic activities. We found that fisetin treatment inhibited PI3K signaling pathway in melanoma cells. Therefore, we investigated the effect of fisetin and sorafenib (an RAF inhibitor) alone and in combination on cell proliferation, apoptosis and tumor growth. Combination treatment (fisetin + sorafenib) more effectively reduced the growth of BRAF-mutated human melanoma cells at lower doses when compared to individual agents. In addition, combination treatment resulted in enhanced (i) apoptosis, (ii) cleavage of caspase-3 and PARP, (iii) expression of Bax and Bak, (iv) inhibition of Bcl2 and Mcl-1, and (v) inhibition of expression of PI3K, phosphorylation of MEK1/2, ERK1/2, AKT and mTOR. In athymic nude mice subcutaneously implanted with melanoma cells (A375 and SK-MEL-28), we found that combination therapy resulted in greater reduction of tumor growth when compared to individual agents. Furthermore, combination therapy was more effective than monotherapy in: (i) inhibition of proliferation and angiogenesis, (ii) induction of apoptosis, and (iii) inhibition of the MAPK and PI3K pathways in xenograft tumors. These data suggest that simultaneous inhibition of both these signaling pathways using combination of fisetin and sorafenib may serve as a therapeutic option for the management of melanoma. PMID:26299806

  14. Epigastric Distress Caused by Esophageal Candidiasis in 2 Patients Who Received Sorafenib Plus Radiotherapy for Hepatocellular Carcinoma: Case Report.

    PubMed

    Chen, Kuo-Hsin; Weng, Meng-Tzu; Chou, Yueh-Hung; Lu, Yueh-Feng; Hsieh, Chen-Hsi

    2016-03-01

    Sorafenib followed by fractionated radiotherapy (RT) has been shown to decrease the phagocytic and candidacidal activities of antifungal agents due to radiosensitization. Moreover, sorafenib has been shown to suppress the immune system, thereby increasing the risk for candida colonization and infection. In this study, we present the 2 hepatocellular carcinoma (HCC) patients suffered from epigastric distress caused by esophageal candidiasis who received sorafenib plus RT. Two patients who had received sorafenib and RT for HCC with bone metastasis presented with hiccups, gastric ulcer, epigastric distress, anorexia, heart burn, and fatigue. Empiric antiemetic agents, antacids, and pain killers were ineffective at relieving symptoms. Panendoscopy revealed diffuse white lesions in the esophagus. Candida esophagitis was suspected. Results of periodic acid-Schiff staining were diagnostic of candidiasis. Oral fluconazole (150 mg) twice daily and proton-pump inhibitors were prescribed. At 2-weak follow-up, esophagitis had resolved and both patients were free of gastrointestinal symptoms. Physicians should be aware that sorafenib combined with RT may induce an immunosuppressive state in patients with HCC, thereby increasing their risk of developing esophagitis due to candida species. PMID:26986168

  15. Epigastric Distress Caused by Esophageal Candidiasis in 2 Patients Who Received Sorafenib Plus Radiotherapy for Hepatocellular Carcinoma: Case Report

    PubMed Central

    Chen, Kuo-Hsin; Weng, Meng-Tzu; Chou, Yueh-Hung; Lu, Yueh-Feng; Hsieh, Chen-Hsi

    2016-01-01

    Abstract Sorafenib followed by fractionated radiotherapy (RT) has been shown to decrease the phagocytic and candidacidal activities of antifungal agents due to radiosensitization. Moreover, sorafenib has been shown to suppress the immune system, thereby increasing the risk for candida colonization and infection. In this study, we present the 2 hepatocellular carcinoma (HCC) patients suffered from epigastric distress caused by esophageal candidiasis who received sorafenib plus RT. Two patients who had received sorafenib and RT for HCC with bone metastasis presented with hiccups, gastric ulcer, epigastric distress, anorexia, heart burn, and fatigue. Empiric antiemetic agents, antacids, and pain killers were ineffective at relieving symptoms. Panendoscopy revealed diffuse white lesions in the esophagus. Candida esophagitis was suspected. Results of periodic acid-Schiff staining were diagnostic of candidiasis. Oral fluconazole (150 mg) twice daily and proton-pump inhibitors were prescribed. At 2-weak follow-up, esophagitis had resolved and both patients were free of gastrointestinal symptoms. Physicians should be aware that sorafenib combined with RT may induce an immunosuppressive state in patients with HCC, thereby increasing their risk of developing esophagitis due to candida species. PMID:26986168

  16. The adverse effects of sorafenib in patients with advanced cancers.

    PubMed

    Li, Ye; Gao, Zu-Hua; Qu, Xian-Jun

    2015-03-01

    Sorafenib is the first multi-kinase inhibitor (TKI) approved for the treatment of advanced hepatocellular cancer (HCC) and metastatic renal cell cancer (RCC) and is increasingly being used to treat patients with well-differentiated radioiodine-resistant thyroid cancer (DTC). Sorafenib demonstrates targeted activity on several families of receptor and non-receptor tyrosine kinases that are involved in angiogenesis, tumour growth and metastatic progression of cancer. Sorafenib treatment results in long-term efficacy and low incidence of life-threatening toxicities. Although sorafenib has demonstrated many benefits in patients, the adverse effects cannot be ignored. The most common treatment-related toxicities include diarrhoea, fatigue, hand-foot skin reaction and hypertension. Most of these toxicities are considered mild to moderate and manageable to varying degrees; however, cardiovascular events might lead to death. In this MiniReview, we summarize the adverse effects of sorafenib that commonly occur in patients with advanced cancers. PMID:25495944

  17. Synergistic inhibition of characteristics of liver cancer stem-like cells with a combination of sorafenib and 8-bromo-7-methoxychrysin in SMMC-7721 cell line.

    PubMed

    Zou, Hui; Cao, Xiaozheng; Xiao, Qiao; Sheng, Xifeng; Ren, Kaiqun; Quan, Meifang; Song, Zhengwei; Li, Duo; Zheng, Yu; Zeng, Wenbin; Cao, Jianguo; Peng, Yaojin

    2016-09-01

    Sorafenib, a multi-kinase inhibitor, has shown its promising antitumor effect in a series of clinical trials, and has been approved as the current standard treatment for advanced hepatocellular carcinoma (HCC). 8-Bromo‑7-methoxychrysin (BrMC) is a novel chrysin synthetic analogue that has been reported to inhibit the growth of various tumor cells and possess properties for targeting liver cancer stem cells (LCSCs) . The present study investigated the synergistic targeting effects on the properties of liver cancer stem-like cells (LCSLCs) by a combination of sorafenib and BrMC in SMMC-7721 cell line. We also investigated whether this effect involves regulation of HIF-1α, Twist and NF-κB protein. We found that the sphere-forming cells (SFCs) from the SMMC‑7721 cells possessed the properties of LCSLCs. Sorafenib diminished the self-renewal capacity and downregulated the expression of stem cell biomarkers (CD133, CD44 and ALDH1) in a dose-dependent manner, while BrMC cooperated with sorafenib to strengthen this inhibition. Moreover, the combination of sorafenib and BrMC led to a remarkable decrease in the cellular migration and invasion, the downregulation of N-cadherin protein and upregulation of E-cadherin protein, and increase of cell apoptosis in LCSLCs. BrMC has a remarkable antagonistic effect on the upregulation of protein expression and DNA binding activity of NF-κB (p65) induced by sorafenib. In addition, our results indicated that the synergistic inhibition of sorafenib and BrMC on the characteristics of LCSLCs involves the downregulated expression of HIF-1α and EMT regulator Twist1. Collectively, the combination therapy of sorafenib and BrMC could be a new and promising therapeutic approach in the treatment of HCC. PMID:27461522

  18. MiR-338-3p Inhibits Hepatocarcinoma Cells and Sensitizes These Cells to Sorafenib by Targeting Hypoxia-Induced Factor 1α

    PubMed Central

    Fang, Qiuju; Sun, Jianmin; Zhang, Songyan; Zhan, Chao; Liu, Shujie; Zhang, Yubao

    2014-01-01

    Hypoxia is a common feature of solid tumors and an important contributor to anti-tumor drug resistance. Hypoxia inducible factor-1 (HIF-1) is one of the key mediators of the hypoxia signaling pathway, and was recently proven to be required for sorafenib resistance in hepatocarcinoma (HCC). MicroRNAs have emerged as important posttranslational regulators in HCC. It was reported that miR-338-3p levels are associated with clinical aggressiveness of HCC. However, the roles of miR-338-3p in HCC disease and resistance to its therapeutic drugs are unknown. In this study, we found that miR-338-3p was frequently down-regulated in 14 HCC clinical samples and five cell lines. Overexpression of miR-338-3p inhibited HIF-1α 3′-UTR luciferase activity and HIF-1α protein levels in HepG2, SMMC-7721, and Huh7 cells. miR-338-3p significantly reduced cell viability and induced cell apoptosis of HCC cells. Additionally, HIF-1α overexpression rescued and HIF-1α knock-down abrogated the anti-HCC activity of miR-338-3p. Furthermore, miR-338-3p sensitized HCC cells to sorafenib in vitro and in a HCC subcutaneous nude mice tumor model by inhibiting HIF-1α. Collectively, miR-338-3p inhibits HCC tumor growth and sensitizes HCC cells to sorafenib by down-regulating HIF-1α. Our data indicate that miR-338-3p could be a potential candidate for HCC therapeutics. PMID:25531114

  19. Hypothyroidism Side Effect in Patients Treated with Sunitinib or Sorafenib: Clinical and Structural Analyses.

    PubMed

    Shu, Mao; Zai, Xiaoli; Zhang, Beina; Wang, Rui; Lin, Zhihua

    2016-01-01

    Tyrosine kinase inhibitors (TKIs) provide more effective targeted treatments for cancer, but are subject to a variety of adverse effects, such as hypothyroidism. TKI-induced hypothyroidism is a highly complicated issue, because of not only the unrealized toxicological mechanisms, but also different incidences of individual TKI drugs. While sunitinib is suspected for causing thyroid dysfunction more often than other TKIs, sorafenib is believed to be less risky. Here we integrated clinical data and in silico drug-protein interactions to examine the pharmacological distinction between sunitinib and sorafenib. Statistical analysis on the FDA Adverse Event Reporting System (FAERS) confirmed that sunitinib is more concurrent with hypothyroidism than sorafenib, which was observed in both female and male patients. Then, we used docking method and identified 3 proteins specifically binding to sunitinib but not sorafenib, i.e., retinoid X receptor alpha, retinoic acid receptors beta and gamma. As potential off-targets of sunitinib, these proteins are well known to assemble with thyroid hormone receptors, which can explain the profound impact of sunitinib on thyroid function. Taken together, we established a strategy of integrated analysis on clinical records and drug off-targets, which can be applied to explore the molecular basis of various adverse drug reactions. PMID:26784451

  20. Hypothyroidism Side Effect in Patients Treated with Sunitinib or Sorafenib: Clinical and Structural Analyses

    PubMed Central

    Shu, Mao; Zai, Xiaoli; Zhang, Beina; Wang, Rui; Lin, Zhihua

    2016-01-01

    Tyrosine kinase inhibitors (TKIs) provide more effective targeted treatments for cancer, but are subject to a variety of adverse effects, such as hypothyroidism. TKI-induced hypothyroidism is a highly complicated issue, because of not only the unrealized toxicological mechanisms, but also different incidences of individual TKI drugs. While sunitinib is suspected for causing thyroid dysfunction more often than other TKIs, sorafenib is believed to be less risky. Here we integrated clinical data and in silico drug-protein interactions to examine the pharmacological distinction between sunitinib and sorafenib. Statistical analysis on the FDA Adverse Event Reporting System (FAERS) confirmed that sunitinib is more concurrent with hypothyroidism than sorafenib, which was observed in both female and male patients. Then, we used docking method and identified 3 proteins specifically binding to sunitinib but not sorafenib, i.e., retinoid X receptor alpha, retinoic acid receptors beta and gamma. As potential off-targets of sunitinib, these proteins are well known to assemble with thyroid hormone receptors, which can explain the profound impact of sunitinib on thyroid function. Taken together, we established a strategy of integrated analysis on clinical records and drug off-targets, which can be applied to explore the molecular basis of various adverse drug reactions. PMID:26784451

  1. A phase I study of the histone deacetylase (HDAC) inhibitor entinostat, in combination with sorafenib in patients with advanced solid tumors.

    PubMed

    Ngamphaiboon, Nuttapong; Dy, Grace K; Ma, Wen Wee; Zhao, Yujie; Reungwetwattana, Thanyanan; DePaolo, Dawn; Ding, Yi; Brady, William; Fetterly, Gerald; Adjei, Alex A

    2015-02-01

    Based on preclinical data demonstrating cytotoxic synergy between sorafenib and entinostat, a phase I study of this combination was conducted in patients with advanced solid tumors. Enrollment followed the traditional "3 + 3" dose escalation scheme. Entinostat was given orally once every 2 weeks, starting at a dose of 4 mg and escalating to 6 and 10 mg every 2 weeks. Sorafenib was administered as a continuous oral dose, escalating from 200 to 400 mg twice daily. A treatment cycle was 28 days. A total of 31 patients with advanced solid tumors were enrolled on the study. The three dose-limiting toxicities (DLTs) observed were grade 3 hand-foot syndrome, nausea/vomiting, and fatigue. MTD was not reached. The recommended phase II dose was defined as the full dose of the respective drugs administered individually. The most common grade 3-4 toxicities were muscle weakness (13 %), skin rash (10 %), fatigue (6 %), diarrhea (6 %), and hand-foot syndrome (3 %). One NSCLC patient achieved a partial response. Two patients (adenocarcinoma of GE junction and Hurthle cell carcinoma of the thyroid) were on the study for more than 9 months with stable disease. The combination of entinostat and sorafenib was well tolerated. Entinostat 10 mg orally once every 2 weeks in combination with sorafenib 400 mg orally twice daily, representing full single agent doses of each drug was identified as the recommended phase 2 dose (RP2D). These data support future clinical development of the combination of entinostat and sorafenib. PMID:25371323

  2. The induction of human myeloid derived suppressor cells through hepatic stellate cells is dose-dependently inhibited by the tyrosine kinase inhibitors nilotinib, dasatinib and sorafenib, but not sunitinib.

    PubMed

    Heine, Annkristin; Schilling, Judith; Grünwald, Barbara; Krüger, Achim; Gevensleben, Heidrun; Held, Stefanie Andrea Erika; Garbi, Natalio; Kurts, Christian; Brossart, Peter; Knolle, Percy; Diehl, Linda; Höchst, Bastian

    2016-03-01

    Increased numbers of immunosuppressive myeloid derived suppressor cells (MDSCs) correlate with a poor prognosis in cancer patients. Tyrosine kinase inhibitors (TKIs) are used as standard therapy for the treatment of several neoplastic diseases. However, TKIs not only exert effects on the malignant cell clone itself but also affect immune cells. Here, we investigate the effect of TKIs on the induction of MDSCs that differentiate from mature human monocytes using a new in vitro model of MDSC induction through activated hepatic stellate cells (HSCs). We show that frequencies of monocytic CD14(+)HLA-DR(-/low) MDSCs derived from mature monocytes were significantly and dose-dependently reduced in the presence of dasatinib, nilotinib and sorafenib, whereas sunitinib had no effect. These regulatory effects were only observed when TKIs were present during the early induction phase of MDSCs through activated HSCs, whereas already differentiated MDSCs were not further influenced by TKIs. Neither the MAPK nor the NFκB pathway was modulated in MDSCs when any of the TKIs was applied. When functional analyses were performed, we found that myeloid cells treated with sorafenib, nilotinib or dasatinib, but not sunitinib, displayed decreased suppressive capacity with regard to CD8+ T cell proliferation. Our results indicate that sorafenib, nilotinib and dasatinib, but not sunitinib, decrease the HSC-mediated differentiation of monocytes into functional MDSCs. Therefore, treatment of cancer patients with these TKIs may in addition to having a direct effect on cancer cells also prevent the differentiation of monocytes into MDSCs and thereby differentially modulate the success of immunotherapeutic or other anti-cancer approaches. PMID:26786874

  3. Sorafenib synergizes with metformin in NSCLC through AMPK pathway activation

    PubMed Central

    Groenendijk, Floris H; Mellema, Wouter W; van der Burg, Eline; Schut, Eva; Hauptmann, Michael; Horlings, Hugo M; Willems, Stefan M; van den Heuvel, Michel M; Jonkers, Jos; Smit, Egbert F; Bernards, René

    2015-01-01

    The multikinase inhibitor sorafenib is under clinical investigation for the treatment of many solid tumors, but in most cases, the molecular target responsible for the clinical effect is unknown. Furthermore, enhancing the effectiveness of sorafenib using combination strategies is a major clinical challenge. Here, we identify sorafenib as an activator of AMP-activated protein kinase (AMPK), in a manner that involves either upstream LKB1 or CAMKK2. We further show in a phase II clinical trial in KRAS mutant advanced non-small cell lung cancer (NSCLC) with single agent sorafenib an improved disease control rate in patients using the antidiabetic drug metformin. Consistent with this, sorafenib and metformin act synergistically in inhibiting cellular proliferation in NSCLC in vitro and in vivo. A synergistic effect of both drugs is also seen on phosphorylation of the AMPKα activation site. Our results provide a rationale for the synergistic antiproliferative effects, given that AMPK inhibits downstream mTOR signaling. These data suggest that the combination of sorafenib with AMPK activators could have beneficial effects on tumor regression by AMPK pathway activation. The combination of metformin or other AMPK activators and sorafenib could be tested in prospective clinical trials. PMID:25080865

  4. Deferasirox, an oral iron chelator, prevents hepatocarcinogenesis and adverse effects of sorafenib

    PubMed Central

    Yamamoto, Naoki; Yamasaki, Takahiro; Takami, Taro; Uchida, Koichi; Fujisawa, Koichi; Matsumoto, Toshihiko; Saeki, Issei; Terai, Shuji; Sakaida, Isao

    2016-01-01

    Although sorafenib is expected to have a chemopreventive effect on hepatocellular carcinoma (HCC) recurrence, there are limitations to its use because of adverse effects, including effects on liver function. We have reported that the iron chelator, deferoxamine can prevent liver fibrosis and preneoplastic lesions. We investigated the influence of administering a new oral iron chelator, deferasirox (DFX), on the effects of sorafenib. We used the choline-deficient l-amino acid-defined (CDAA) diet-induced rat liver fibrosis and HCC model. We divided rats into four groups: CDAA diet only (control group), CDAA diet with sorafenib (sorafenib group), CDAA diet with DFX (DFX group), and CDAA diet with DFX and sorafenib (DFX + sorafenib group). Liver fibrosis and development of preneoplastic lesions were assessed. In addition, we assessed adverse effects such as changes in body and liver weight, skin damage (eruption, dryness, and hair loss), which is defined as hand-foot skin syndrome, in the sorafenib and DFX + sorafenib groups. The combination of DFX + sorafenib markedly prevented liver fibrosis and preneoplastic lesions better than the other treatments. Furthermore, the combination therapy significantly decreased adverse effects compared with the sorafenib group. In conclusion, the combination therapy with DFX and sorafenib may be a useful adjuvant therapy to prevent recurrence after curative treatment of HCC. PMID:27257345

  5. Prognostic significance of adverse events in patients with hepatocellular carcinoma treated with sorafenib

    PubMed Central

    Granito, Alessandro; Marinelli, Sara; Negrini, Giulia; Menetti, Saverio; Benevento, Francesca; Bolondi, Luigi

    2016-01-01

    Sorafenib is the standard treatment for patients with hepatocellular carcinoma (HCC) with advanced stage disease. Although its effectiveness has been demonstrated by randomized clinical trials and confirmed by field practice studies, reliable markers predicting therapeutic response have not yet been identified. Like other tyrosine kinase inhibitors, treatment with sorafenib is burdened by the development of adverse effects, the most frequent being cutaneous toxicity, diarrhoea, arterial hypertension and fatigue. In recent years, several studies have analysed the correlation between off-target effects and sorafenib efficacy in patients with HCC. In this review, an overview of the studies assessing the prognostic significance of sorafenib-related adverse events is provided. PMID:26929785

  6. Reversible Decrease of Portal Venous Flow in Cirrhotic Patients: A Positive Side Effect of Sorafenib

    PubMed Central

    Coriat, Romain; Gouya, Hervé; Mir, Olivier; Ropert, Stanislas; Vignaux, Olivier; Chaussade, Stanislas; Sogni, Philippe; Pol, Stanislas; Blanchet, Benoit

    2011-01-01

    Portal hypertension, the most important complication with cirrhosis of the liver, is a serious disease. Sorafenib, a tyrosine kinase inhibitor is validated in advanced hepatocellular carcinoma. Because angiogenesis is a pathological hallmark of portal hypertension, the goal of our study was to determine the effect of sorafenib on portal venous flow and portosystemic collateral circulation in patients receiving sorafenib therapy for advanced hepatocellular carcinoma. Porto-collateral circulations were evaluated using a magnetic resonance technique prior sorafenib therapy, and at day 30. All patients under sorafenib therapy had a decrease in portal venous flow of at least 36%. In contrast, no specific change was observed in the azygos vein or the abdominal aorta. No portal venous flow modification was observed in the control group. Sorafenib is the first anti-angiogenic therapy to demonstrate a beneficial and reversible decrease of portal venous flow among cirrhotic patients. PMID:21340026

  7. Monitoring Serum Levels of Sorafenib and Its N-Oxide Is Essential for Long-Term Sorafenib Treatment of Patients with Hepatocellular Carcinoma.

    PubMed

    Shimada, Miki; Okawa, Hoshimi; Kondo, Yasuteru; Maejima, Takahiro; Kataoka, Yuta; Hisamichi, Kanehiko; Maekawa, Masamitsu; Matsuura, Masaki; Jin, Yuko; Mori, Masaru; Suzuki, Hiroyuki; Shimosegawa, Tooru; Mano, Nariyasu

    2015-01-01

    Sorafenib, an oral multi-kinase inhibitor, is the final therapy prior to palliative care for advanced hepatocellular carcinoma (HCC). However, due to its adverse effects, 20% of patients must discontinue sorafenib within 1 month after first administration. To identify ways to predict the adverse effects and administer the drug for longer periods, we explored the relationship between the duration of sorafenib treatment and the pharmacokinetics of sorafenib and its major metabolite, sorafenib N-oxide. Twenty-five subjects enrolled in the study were divided into two groups: patients with dosage reduced or withdrawn due to adverse effects (n = 8), and patients with dosage maintained for 1 month after initial administration (n = 17). We evaluated early sorafenib accumulation as the area under the curve of sorafenib and sorafenib N-oxide concentrations during days 1-7 (AUC(sorafenib) and AUC(N-oxide), respectively). Inter-group comparison revealed that AUC(N-oxide) and AUC ratio (AUC(N-oxide)/AUC(sorafenib)) were significantly higher in the dosage reduction/withdrawal group (P = 0.031 and P = 0.0022, respectively). Receiver operating characteristic analysis indicated that AUC(N-oxide) and AUC ratio were reliable predictors of adverse effects. When patients were classified by cut-off points (AUC(N-oxide:) 2.0 μg ∙ day/mL, AUC ratio: 0.13), progression-free survival was significantly longer in patients with AUC(N-oxide) ≤ 2.0 μg ∙ day/mL (P = 0.0048, log-rank test). In conclusion, we recommend to simultaneously monitor serum levels of sorafenib and its N-oxide during the early stage after the first administration, which enables us to provide safe and long-term therapy for each HCC patient with sorafenib. PMID:26477611

  8. Sorafenib and sunitinib: A dermatologist's perspective

    PubMed Central

    Pragasam, Vijendran; Verma, Rajesh; Vasudevan, Biju

    2014-01-01

    Sorafenib and sunitinib are inhibitors of tumor angiogenesis have recently generated curiosity regarding its role in cutaneous toxicities, which has severely affected the daily activities resulting in interruption or dose modification of therapy in renal cell carcinoma and hepatocellular carcinomas. We discuss the pathophysiology, adverse cutaneous effects and their grading, potential high risk factors, role of gene polymorphism, critical period of hand-foot skin reaction development and their management. PMID:24616845

  9. Life Beyond Kinases: Structure-based Discovery of Sorafenib as Nanomolar Antagonist of 5-HT Receptors

    PubMed Central

    Lin, Xingyu; Huang, Xi-Ping; Chen, Gang; Whaley, Ryan; Peng, Shiming; Wang, Yanli; Zhang, Guoliang; Wang, Simon X.; Wang, Shaohui; Roth, Bryan L.; Huang, Niu

    2012-01-01

    Of great interest in recent years has been computationally predicting the novel polypharmacology of drug molecules. Here, we applied an “induced-fit” protocol to improve the homology models of 5-HT2A receptor, and we assessed the quality of these models in retrospective virtual screening. Subsequently, we computationally screened the FDA approved drug molecules against the best induced-fit 5-HT2A models, and chose six top scoring hits for experimental assays. Surprisingly, one well-known kinase inhibitor, sorafenib has shown unexpected promiscuous 5-HTRs binding affinities, Ki = 1959, 56 and 417 nM against 5-HT2A, 5-HT2B and 5-HT2C, respectively. Our preliminary SAR exploration supports the predicted binding mode, and further suggests sorafenib to be a novel lead compound for 5HTR ligand discovery. Although it has been well known that sorafenib produces anticancer effects through targeting multiple kinases, carefully designed experimental studies are desirable to fully understand whether its “off-target” 5-HTR binding activities contribute to its therapeutic efficacy or otherwise undesirable side effects. PMID:22694093

  10. Sorafenib and nilotinib resensitize tamoxifen resistant breast cancer cells to tamoxifen treatment via estrogen receptor α.

    PubMed

    Pedersen, Astrid M; Thrane, Susan; Lykkesfeldt, Anne E; Yde, Christina W

    2014-11-01

    Tamoxifen‑resistant breast cancer is a major clinical problem and new treatment strategies are highly warranted. In this study, the multitargeting kinase inhibitors sorafenib and nilotinib were investigated as potential new treatment options for tamoxifen‑resistant breast cancer. The two compounds inhibited cell growth, reduced expression of total estrogen receptor α (ER), Ser118-phosphorylated ER, FOXA1 and AIB1 and resensitized tamoxifen‑resistant cells to tamoxifen. The ER downmodulator fulvestrant exerted strong growth inhibition of tamoxifen‑resistant cells and addition of sorafenib and nilotinib could not further suppress growth, showing that sorafenib and nilotinib exerted growth inhibition via ER. In support of this, estradiol prevented sorafenib and nilotinib mediated growth inhibition. These results demonstrate that sorafenib and nilotinib act via ER and ER-associated proteins, indicating that these kinase inhibitors in combination with tamoxifen may be potential new treatments for tamoxifen‑resistant breast cancer. PMID:25175082

  11. Connexin-dependent gap junction enhancement is involved in the synergistic effect of sorafenib and all-trans retinoic acid on HCC growth inhibition.

    PubMed

    Yang, Yan; Qin, Shu-Kui; Wu, Qiong; Wang, Zi-Shu; Zheng, Rong-Sheng; Tong, Xu-Hui; Liu, Hao; Tao, Liang; He, Xian-Di

    2014-02-01

    Increasing gap junction activity in tumor cells provides a target by which to enhance antineoplastic therapies. Previously, several naturally occurring agents, including all-trans retinoic acid (ATRA) have been demonstrated to increase gap junctional intercellular communication (GJIC) in a number of types of cancer cells. In the present study, we investigated in vitro whether ATRA modulates the response of human hepatocellular carcinoma (HCC) cells to sorafenib, the only proven oral drug for advanced HCC, and the underlying mechanisms. HepG2 and SMMC-7721 cells were treated with sorafenib and/or ATRA, and cell proliferation and apoptosis were analyzed; the role of GJIC was also explored. We found that ATRA, at non-toxic concentrations, enhanced sorafenib-induced growth inhibition in both HCC cell lines, and this effect was abolished by two GJIC inhibitors, 18-α-GA and oleamide. Whereas lower concentrations of sorafenib (5 µM) or ATRA (0.1 or 10 µM) alone modestly induced GJIC activity, the combination of sorafenib plus ATRA resulted in a strong enhancement of GJIC. However, the action paradigm differed in the HepG2 and SMMC-7721 cells, with the dominant effect of GJIC dependent on the cell-specific connexin increase in protein amounts and relocalization. RT-PCR assay further revealed a transcriptional modification of the key structural connexin in the two cell lines. Thus, a connexin-dependent gap junction enhancement may play a central role in ATRA plus sorafenib synergy in inhibiting HCC cell growth. Since both agents are available for human use, the combination treatment represents a future profitable strategy for the treatment of advanced HCC. PMID:24317203

  12. Physiologically based pharmacokinetic models for everolimus and sorafenib in mice

    PubMed Central

    Pawaskar, Dipti K.; Straubinger, Robert M.; Fetterly, Gerald J.; Hylander, Bonnie H.; Repasky, Elizabeth A.; Ma, Wen W.

    2013-01-01

    Purpose Everolimus is a mammalian target of rapamycin (mTOR) inhibitor approved as an immunosuppressant and for second-line therapy of hepatocellular carcinoma (HCC) and renal cell carcinoma (RCC). Sorafenib is a multikinase inhibitor used as first-line therapy in HCC and RCC. This study assessed the pharmacokinetics (PK) of everolimus and sorafenib alone and in combination in plasma and tissues, developed physiologically based pharmacokinetic (PBPK) models in mice, and assessed the possibility of PK drug interactions. Methods Single and multiple oral doses of everolimus and sorafenib were administered alone and in combination in immunocompetent male mice and to severe combined immune-deficient (SCID) mice bearing low-passage, patient-derived pancreatic adenocarcinoma in seven different studies. Plasma and tissue samples including tumor were collected over a 24-h period and analyzed by liquid chromatography-tandem mass spectrometry (LC–MS/MS). Distribution of everolimus and sorafenib to the brain, muscle, adipose, lungs, kidneys, pancreas, spleen, liver, GI, and tumor was modeled as perfusion rate-limited, and all data from the diverse studies were fitted simultaneously using a population approach. Results PBPK models were developed for everolimus and sorafenib. PBPK analysis showed that the two drugs in combination had the same PK as each drug given alone. A twofold increase in sorafenib dose increased tumor exposure tenfold, thus suggesting involvement of transporters in tumor deposition of sorafenib. Conclusions The developed PBPK models suggested the absence of PK interaction between the two drugs in mice. These studies provide the basis for pharmacodynamic evaluation of these drugs in patient-derived primary pancreatic adenocarcinomas explants. PMID:23455451

  13. Deteriorated portal flow may cause liver failure in patients with hepatocellular carcinoma being treated with sorafenib.

    PubMed

    Yamasaki, Akihiro; Umeno, Narihiro; Harada, Shigeru; Tanaka, Kosuke; Kato, Masaki; Kotoh, Kazuhiro

    2016-06-01

    We encountered two patients with hepatocellular carcinoma (HCC) who showed rapid progression of liver failure during sorafenib treatment. One had portal vein tumor thrombus (PVTT) and the other developed portal vein thrombosis (PVT) during the treatment, and both of them experienced the elevation of serum lactate dehydrogenase (LDH) concentration during the administration of sorafenib. Their clinical courses indicate that the liver failure might have been caused by sorafenib-induced liver hypoxia, being amplified in the circumstances with reduced portal flow. To our best knowledge, all the reported patients who achieved complete remission (CR) during sorafenib monotherapy had a condition that could decrease portal blood flow. We hypothesized that pathogenesis of disease may be similar in HCC patients who achieve CR and those who experience liver failure while on sorafenib. Sorafenib treatment of patients with HCC and deteriorated portal flow may be a double-edged sword. PMID:27284486

  14. Deteriorated portal flow may cause liver failure in patients with hepatocellular carcinoma being treated with sorafenib

    PubMed Central

    Yamasaki, Akihiro; Umeno, Narihiro; Harada, Shigeru; Tanaka, Kosuke; Kato, Masaki

    2016-01-01

    We encountered two patients with hepatocellular carcinoma (HCC) who showed rapid progression of liver failure during sorafenib treatment. One had portal vein tumor thrombus (PVTT) and the other developed portal vein thrombosis (PVT) during the treatment, and both of them experienced the elevation of serum lactate dehydrogenase (LDH) concentration during the administration of sorafenib. Their clinical courses indicate that the liver failure might have been caused by sorafenib-induced liver hypoxia, being amplified in the circumstances with reduced portal flow. To our best knowledge, all the reported patients who achieved complete remission (CR) during sorafenib monotherapy had a condition that could decrease portal blood flow. We hypothesized that pathogenesis of disease may be similar in HCC patients who achieve CR and those who experience liver failure while on sorafenib. Sorafenib treatment of patients with HCC and deteriorated portal flow may be a double-edged sword. PMID:27284486

  15. Inhibition of tumor growth and metastasis by photoimmunotherapy targeting tumor-associated macrophage in a sorafenib-resistant tumor model.

    PubMed

    Zhang, Chenran; Gao, Liquan; Cai, Yuehong; Liu, Hao; Gao, Duo; Lai, Jianhao; Jia, Bing; Wang, Fan; Liu, Zhaofei

    2016-04-01

    Tumor-associated macrophages (TAMs) play essential roles in tumor invasion and metastasis, and contribute to drug resistance. Clinical evidence suggests that TAM levels are correlated with local tumor relapse, distant metastasis, and poor prognosis in patients. In this study, we synthesized a TAM-targeted probe (IRD-αCD206) by conjugating a monoclonal anti-CD206 antibody with a near-infrared phthalocyanine dye. We then investigated the potential application of the IRD-αCD206 probe to near-infrared fluorescence (NIRF) imaging and photoimmunotherapy (PIT) of tumors resistant to treatment with the kinase inhibitor sorafenib. Sorafenib treatment had no effect on tumor growth in a 4T1 mouse model of breast cancer, but induced M2 macrophage polarization in tumors. M2 macrophage recruitment by sorafenib-treated 4T1 tumors was noninvasively visualized by in vivo NIRF imaging of IRD-αCD206. Small-animal single-photon emission computed tomography (SPECT)/CT and intratumoral microdistribution analysis indicated TAM-specific localization of the IRD-αCD206 probe in 4T1 tumors after several rounds of sorafenib treatment. Upon light irradiation, IRD-αCD206 suppressed the growth of sorafenib-resistant tumors. In vivo CT imaging and ex vivo histological analysis confirmed the inhibition of lung metastasis in mice by IRD-αCD206 PIT. These results demonstrate the utility of the IRD-αCD206 probe for TAM-targeted diagnostic imaging and treatment of tumors that are resistant to conventional therapeutics. PMID:26803407

  16. Quantitation of sorafenib and its active metabolite sorafenib N-oxide in human plasma by liquid chromatography-tandem mass spectrometry.

    PubMed

    Li, Lie; Zhao, Ming; Navid, Fariba; Pratz, Keith; Smith, B Doug; Rudek, Michelle A; Baker, Sharyn D

    2010-11-01

    A simple and rapid method with high performance liquid chromatography/tandem mass spectrometry is described for the quantitation of the kinase inhibitor sorafenib and its active metabolite sorafenib N-oxide in human plasma. A protein precipitation extraction procedure was applied to 50 μL of plasma. Chromatographic separation of the two analytes, and the internal standard [(2)H(3)(13)C]-sorafenib, was achieved on a C(18) analytical column and isocratic flow at 0.3 mL/min for 4 min. Mean within-run and between-run precision for all analytes were <6.9% and accuracy was <5.3%. Calibration curves were linear over the concentration range of 50-10,000 ng/mL for sorafenib and 10-2500 ng/mL for sorafenib N-oxide. This method allows a specific, sensitive, and reliable determination of the kinase inhibitor sorafenib and its active metabolite sorafenib N-oxide in human plasma in a single analytical run. PMID:20870468

  17. Clinical observation of liver cancer patients treated with axitinib and cabozantinib after failed sorafenib treatment: a case report and literature review

    PubMed Central

    Zhang, Bin; Zhang, Xia; Zhou, Tao; Liu, Jiwei

    2015-01-01

    Hepatocellular carcinoma (HCC) is a major pathological type of primary liver cancer. Sorafenib has demonstrated definite efficacy in targeted therapy for HCC. However, when treatment with sorafenib fails, suitable drugs must be found for further treatment. This article reports a case of an HCC patient who was treated with angiogenesis inhibitor axitinib and c-Met inhibitor cabozantinib following treatment with sorafenib. The report focuses on clinical treatment and toxicity. Rational application of targeted therapy is also explored. PMID:25668362

  18. S-Adenosyl-l-methionine-competitive inhibitors of the histone methyltransferase EZH2 induce autophagy and enhance drug sensitivity in cancer cells

    PubMed Central

    Liu, Tsang-Pai; Lo, Hsiang-Ling; Wei, Li-Shan; Hao-yun Hsiao, Heidi

    2015-01-01

    The enhancer of zeste homolog 2 (EZH2) has emerged as a novel anticancer target. Various EZH2 inhibitors have been developed in recent years. Among these, 3-deazaneplanocin A (DZNep) is known to deplete EZH2 protein expression through an indirect pathway. In contrast, GSK343 directly inhibits enzyme activity through an S-adenosyl-l-methionine-competitive pathway. Therefore, we proposed that DZNep and GSK343 may exert differential effects against cancer cells. In this study, we found that GSK343 but not DZNep induced autophagic cell death of cancer cells. Inhibition of EZH2 expression was not required for GSK343-induced autophagy. In addition, GSK343 enhanced the anticancer activity of a multikinase inhibitor, sorafenib, in human hepatocellular carcinoma cells. Our results show that GSK343 is a more potent anticancer agent than DZNep, and for the first time, we show that it acts as an autophagy inducer. PMID:25203626

  19. Inhibition of Cell Proliferation in an NRAS Mutant Melanoma Cell Line by Combining Sorafenib and α-Mangostin.

    PubMed

    Xia, Yun; Li, Ying; Westover, Kenneth D; Sun, Jiaming; Chen, Hongxiang; Zhang, Jianming; Fisher, David E

    2016-01-01

    α-Mangostin is a natural product commonly used in Asia for cosmetic and medicinal applications including topical treatment of acne and skin cancer. Towards finding new pharmacological strategies that overcome NRAS mutant melanoma, we performed a cell proliferation-based combination screen using a collection of well-characterized small molecule kinase inhibitors and α-Mangostin. We found that α-Mangostin significantly enhances Sorafenib pharmacological efficacy against an NRAS mutant melanoma cell line. The synergistic effects of α-Mangostin and Sorafenib were associated with enhanced inhibition of activated AKT and ERK, induced ER stress, and reduced autophagy, eventually leading to apoptosis. The structure of α-Mangostin resembles several inhibitors of the Retinoid X receptor (RXR). MITF expression, which is regulated by RXR, was modulated by α-Mangostin. Molecular docking revealed that α-Mangostin can be accommodated by the ligand binding pocket of RXR and may thereby compete with RXR-mediated control of MITF expression. In summary, these data demonstrate an unanticipated synergy between α-Mangostin and sorafenib, with mechanistic actions that convert a known safe natural product to a candidate combinatorial therapeutic agent. PMID:27152946

  20. Inhibition of Cell Proliferation in an NRAS Mutant Melanoma Cell Line by Combining Sorafenib and α-Mangostin

    PubMed Central

    Xia, Yun; Li, Ying; Westover, Kenneth D.; Sun, Jiaming; Chen, Hongxiang; Zhang, Jianming; Fisher, David E.

    2016-01-01

    α-Mangostin is a natural product commonly used in Asia for cosmetic and medicinal applications including topical treatment of acne and skin cancer. Towards finding new pharmacological strategies that overcome NRAS mutant melanoma, we performed a cell proliferation-based combination screen using a collection of well-characterized small molecule kinase inhibitors and α-Mangostin. We found that α-Mangostin significantly enhances Sorafenib pharmacological efficacy against an NRAS mutant melanoma cell line. The synergistic effects of α-Mangostin and Sorafenib were associated with enhanced inhibition of activated AKT and ERK, induced ER stress, and reduced autophagy, eventually leading to apoptosis. The structure of α-Mangostin resembles several inhibitors of the Retinoid X receptor (RXR). MITF expression, which is regulated by RXR, was modulated by α-Mangostin. Molecular docking revealed that α-Mangostin can be accommodated by the ligand binding pocket of RXR and may thereby compete with RXR-mediated control of MITF expression. In summary, these data demonstrate an unanticipated synergy between α-Mangostin and sorafenib, with mechanistic actions that convert a known safe natural product to a candidate combinatorial therapeutic agent. PMID:27152946

  1. Effects of Sorafenib Dose on Acquired Reversible Resistance and Toxicity in Hepatocellular Carcinoma.

    PubMed

    Kuczynski, Elizabeth A; Lee, Christina R; Man, Shan; Chen, Eric; Kerbel, Robert S

    2015-06-15

    Acquired evasive resistance is a major limitation of hepatocellular carcinoma (HCC) treatment with the tyrosine kinase inhibitor (TKI) sorafenib. Recent findings suggest that resistance to sorafenib may have a reversible phenotype. In addition, loss of responsiveness has been proposed to be due to a gradual decrease in sorafenib plasma levels in patients. Here, the possible mechanisms underlying reversible sorafenib resistance were investigated using a Hep3B-hCG orthotopic human xenograft model of locally advanced HCC. Tissue and plasma sorafenib and metabolite levels, downstream antitumor targets, and toxicity were assessed during standard and dose-escalated sorafenib treatment. Drug levels were found to decline significantly over time in mice treated with 30 mg/kg sorafenib, coinciding with the onset of resistance but a greater magnitude of change was observed in tissues compared with plasma. Skin rash also correlated with drug levels and tended to decrease in severity over time. Drug level changes appeared to be partially tumor dependent involving induction of tumoral CYP3A4 metabolism, with host pretreatment alone unable to generate resistance. Escalation from 30 to 60 mg/kg sorafenib improved antitumor efficacy but worsened survival due to excessive body weight loss. Microvessel density was inhibited by sorafenib treatment but remained suppressed over time and dose increase. In conclusion, tumor CYP3A4 induction by sorafenib is a novel mechanism to account for variability in systemic drug levels; however, declining systemic sorafenib levels may only be a minor resistance mechanism. Escalating the dose may be an effective treatment strategy, provided toxicity can be controlled. PMID:25908587

  2. Metformin synergistically sensitizes FLT3-ITD-positive acute myeloid leukemia to sorafenib by promoting mTOR-mediated apoptosis and autophagy.

    PubMed

    Wang, Fangfang; Liu, Zuofeng; Zeng, Jisha; Zhu, Hongyan; Li, Jingjing; Cheng, Xiaomin; Jiang, Tao; Zhang, Li; Zhang, Chuanfen; Chen, Tie; Liu, Ting; Jia, Yongqian

    2015-12-01

    Mutations of Fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), accounting for approximately 30% of patients with acute myeloid leukemia (AML), results in poor therapeutic efficacy and short survival. Sorafenib, an oral multikinase inhibitor, can inhibit FLT3 and improve clinical outcome of FLT3 mutated leukemia. Our current studies have shown that, the antidiabetic drug metformin also exerts anti-leukemic effect by activating p-AMPK and synergistically sensitizes FLT3 mutated AML to sorafenib. Both agents suppress cell proliferation in a dose-dependent manner and induce apoptosis via cell cycle arrest, but does not obviously modulate autophagy marker, light chain 3 (LC3). Mechanistically, in the presence of metformin, the anticancer potential of sorafenib, accompanying with increased LC3 levels, is found to be synergistically enhanced with the remarkably reduced protein expression of the mTOR/p70S6K/4EBP1 pathway, while not appreciably altering cell cycle. Overall, these results show metformin in aid of sorafenib may represent a promising and attractive strategy for the treatment of FLT3-ITD mutated AML. PMID:26505133

  3. Management of sorafenib-related adverse events: a clinician's perspective.

    PubMed

    Brose, Marcia S; Frenette, Catherine T; Keefe, Stephen M; Stein, Stacey M

    2014-02-01

    Sorafenib, a tyrosine kinase inhibitor, is approved for the treatment of patients with unresectable hepatocellular carcinoma (HCC) and advanced renal cell carcinoma (RCC). It is being evaluated in phase II and III clinical trials, which include treatment as a single agent (locally advanced/metastatic radioactive iodine-refractory differentiated thyroid cancer [DTC]), as part of multimodality care (HCC), and in combination with chemotherapeutic agents (metastatic breast cancer). Sorafenib-related adverse events (AEs) that commonly occur across these tumor types include hand-foot skin reaction (HSFR), rash, upper and lower gastrointestinal (GI) distress (ie, diarrhea), fatigue, and hypertension. These commonly range from grade 1 to 3, per the Common Terminology Criteria for Adverse Events (CTCAE), and often occur early in treatment. The goal for the management of these AEs is to prevent, treat, and/or minimize their effects, thereby enabling patients to remain on treatment and improve their quality of life. Proactive management, along with ongoing patient education (before and during sorafenib treatment), can help to effectively manage symptoms, often without the need for sorafenib dose modification or drug holidays. Effective management techniques for common sorafenib-related AEs, as well other important disease sequelae not directly related to treatment, are presented. Recommendations and observations are based on physician/author experience and recommendations from published literature. PMID:24576654

  4. [Side effect management of tyrosine kinase inhibitors in urology : Hypertension].

    PubMed

    Sikic, D; Meidenbauer, N; Lieb, V; Keck, B

    2016-07-01

    Tyrosine kinase inhibitors like sunitinib, sorafenib, pazopanib or axintinib are regarded the standard of care in the systemic therapy of metastatic renal cell carcinoma. However, the many side effects associated with this therapy pose challenges for the treating physician and the patient. This review offers an overview of the classification and the treatment of hypertension, which is one of the major side effects induced by all tyrosine kinase inhibitors, in order to improve treatment efficacy and patient compliance. PMID:27146871

  5. MiR-101 targets DUSP1 to regulate the TGF-β secretion in sorafenib inhibits macrophage-induced growth of hepatocarcinoma

    PubMed Central

    Wei, Xufu; Tang, Chengyong; Lu, Xiuxian; Liu, Rui; Zhou, Mi; He, Diao; Zheng, Daofeng; Sun, Chao; Wu, Zhongjun

    2015-01-01

    Hepatocellular carcinoma (HCC)-associated macrophages accelerate tumor progression via growth factor release. Therefore, tumor-associated macrophages (TAMs)-initiated signaling cascades are potential therapeutic targets. To better understand anticancer effects of systemic HCC therapy, we studied sorafenib's effect on macrophage function, focusing on macrophage-related growth factor secretion. We found that dual specificity phosphatase 1 (DUSP1) is a direct target of miR-101. Transfection of miR-101 reduced DUSP1 induction in M2 macrophages and prolonged ERK1/2, p38 and JNK activation, whereas inhibition of miR-101 enhanced DUSP1 expression and decreased ERK1/2, p38 and JNK activation. miR-101 expression was decreased by sorafenib, and inhibition of PI3K/AKT blocked induction of miR-101 by LPS in M2 cells. M2 cells with greater TGF-β and CD206 mRNA expression compared to M1 cells had increased hepatoma growth, metastases and EMT. Sorafenib inhibited miR-101 expression and enhanced DUSP1 expression and lowered TGF-β and CD206 release in M2 cells, slowing macrophage-driven HCC. Our studies demonstrate miR-101 regulates macrophage innate immune responses to LPS via targeting DUSP1. Sorafenib alters macrophage polarization, reduces TGF-β driven cancer growth, metastases and EMT in vitro, and partially inhibits macrophage activation in vivo. Thus, macrophage modulation might explain the anticancer effects of sorafenib. PMID:26158762

  6. A quantitative HPLC-UV method for determination of serum sorafenib and sorafenib N-oxide and its application in hepatocarcinoma patients.

    PubMed

    Shimada, Miki; Okawa, Hoshimi; Maejima, Takahiro; Yanagi, Toshiki; Hisamichi, Kanehiko; Matsuura, Masaki; Akasaka, Kazutoshi; Tsuchiya, Masami; Kondo, Yasuteru; Shimosegawa, Tooru; Mori, Masaru; Maekawa, Masamitsu; Suzuki, Hiroyuki; Mano, Nariyasu

    2014-01-01

    Sorafenib, an oral multi-kinase inhibitor, has been approved for treatment of advanced renal-cell and hepatocellular carcinoma (HCC). However, 20% of HCC patients taking sorafenib are forced to withdraw due to adverse effects within one month after administration. Orally administered sorafenib is oxidatively metabolized, predominantly by cytochrome P450 3A4 (CYP3A4), in small-intestinal mucosa or liver. We aimed to characterize the CYP3A4-mediated metabolism of sorafenib in HCC patients and explore the contribution of the major metabolite sorafenib N-oxide to adverse effects and therapeutic efficacy. We have therefore developed a method for quantitative determination of sorafenib and its N-oxide in the present study. To optimize the preanalytical procedure, we initially ascertained the solubility of the analytes. Because they are lipophilic, solvents containing more than 40% acetonitrile were required for efficient recovery. The pretreatment procedure that we ultimately developed consists of acetonitrile precipitation, followed by extraction using octadecyl silyl-silica gel to eliminate water-soluble and hydrophilic components of serum. Application of this procedure before HPLC enabled accurate and reproducible quantitation of analytes in a linear range from 0.03 to 30 μg/mL. After characterizing the peaks in the HPLC-ultraviolet chromatogram obtained from a medicated patient by LC-tandem mass spectrometry, we applied this method to HCC patients taking sorafenib, showing large inter-individual differences in the pharmacokinetic profile. In conclusion, our assay system should be useful for follow-up of patients taking sorafenib and for exploring the association between the pharmacokinetics of sorafenib and its N-oxide and the adverse effects or therapeutic efficacy. PMID:24872323

  7. Sorafenib for Metastatic Thyroid Cancer

    Cancer.gov

    A summary of results from an international phase III trial that compared sorafenib (Nexavar®) and a placebo for the treatment of locally advanced or metastatic differentiated thyroid cancer that is no longer responding to treatment with radioactive iodine

  8. GSK-3 inhibition in vitro and in vivo enhances antitumor effect of sorafenib in renal cell carcinoma (RCC)

    SciTech Connect

    Kawazoe, Hisashi; Bilim, Vladimir N.; Ugolkov, Andrey V.; Yuuki, Kaori; Naito, Sei; Nagaoka, Akira; Kato, Tomoyuki; Tomita, Yoshihiko

    2012-07-06

    Highlights: Black-Right-Pointing-Pointer Sorafenib treatment upregulated GSK-3{beta} levels in RCC cells. Black-Right-Pointing-Pointer Pharmacologic inhibition of GSK-3 suppressed xenograft RCC tumor growth. Black-Right-Pointing-Pointer Inhibition of GSK-3 enhanced antitumor effect of sorafenib in vitro and in vivo. -- Abstract: Sorafenib is a multikinase inhibitor approved for the systemic treatment of renal cell carcinoma (RCC). However, sorafenib treatment has a limited effect due to acquired chemoresistance of RCC. Previously, we identified glycogen synthase kinase-3 (GSK-3) as a new therapeutic target in RCC. Here, we observed that sorafenib inhibits proliferation and survival of RCC cells. Significantly, we revealed that sorafenib enhances GSK-3 activity in RCC cells, which could be a potential mechanism of acquired chemoresistance. We found that pharmacological inhibition of GSK-3 potentiates sorafenib antitumor effect in vitro and in vivo. Our results suggest that combining GSK-3 inhibitor and sorafenib might be a potential new therapeutic approach for RCC treatment.

  9. NUPR1, a new target in liver cancer: implication in controlling cell growth, migration, invasion and sorafenib resistance.

    PubMed

    Emma, M R; Iovanna, J L; Bachvarov, D; Puleio, R; Loria, G R; Augello, G; Candido, S; Libra, M; Gulino, A; Cancila, V; McCubrey, J A; Montalto, G; Cervello, M

    2016-01-01

    Sorafenib, an oral multikinase inhibitor, is the only approved agent for the treatment of advanced hepatocellular carcinoma (HCC). However, its benefits are modest, and as its mechanisms of action remain elusive, a better understanding of its anticancer effects is needed. Based on our previous study results, we investigated here the implication of the nuclear protein 1 (NUPR1) in HCC and its role in sorafenib treatment. NUPR1 is a stress-inducible protein that is overexpressed in various malignancies, but its role in HCC is not yet fully understood. We found that NUPR1 expression was significantly higher in primary human HCC samples than in the normal liver. Knockdown of NUPR1 significantly increased cell sensitivity to sorafenib and inhibited the cell growth, migration and invasion of HCC cells, both in vitro and in vivo. Moreover, NUPR1 silencing influenced the expression of RELB and IER3 genes. Unsurprisingly, RELB and IER3 knockdown also inhibited HCC cell viability, growth and migration. Using gene expression profiling of HCC cells following stable NUPR1 knockdown, we found that genes functionally involved in cell death and survival, cellular response to therapies, lipid metabolism, cell growth and proliferation, molecular transport and cellular movement were mostly suppressed. Network analysis of dynamic gene expression identified NF-κB and ERK as downregulated gene nodes, and several HCC-related oncogenes were also suppressed. We identified Runt-related transcription factor 2 (RUNX2) gene as a NUPR1-regulated gene and demonstrated that RUNX2 gene silencing inhibits HCC cell viability, growth, migration and increased cell sensitivity to sorafenib. We propose that the NUPR1/RELB/IER3/RUNX2 pathway has a pivotal role in hepatocarcinogenesis. The identification of the NUPR1/RELB/IER3/RUNX2 pathway as a potential therapeutic target may contribute to the development of new treatment strategies for HCC management. PMID:27336713

  10. Inactivation of hypoxia-induced YAP by statins overcomes hypoxic resistance tosorafenib in hepatocellular carcinoma cells

    PubMed Central

    Zhou, Tian-yi; Zhuang, Lin-han; Hu, Yan; Zhou, Yu-lu; Lin, Wen-kai; Wang, Dan-dan; Wan, Zi-qian; Chang, Lin-lin; Chen, Ying; Ying, Mei-dan; Chen, Zi-bo; Ye, Song; Lou, Jian-shu; He, Qiao-jun; Zhu, Hong; Yang, Bo

    2016-01-01

    Sorafenib is a multikinase inhibitor used as a first-line treatment for advanced hepatocellular carcinoma (HCC), but it has shown modest to low response rates. The characteristic tumour hypoxia of advanced HCC maybe a major factor underlying hypoxia-mediated treatment failure. Thus, it is urgent to elucidate the mechanisms of hypoxia-mediated sorafenib resistance in HCC. In this study, we found that hypoxia induced the nuclear translocation of Yes associate-Protein (YAP) and the subsequent transactivation of target genes that promote cell survival and escape apoptosis, thereby leading to sorafenib resistance. Statins, the inhibitors of hydroxymethylglutaryl-CoA reductase, could ameliorate hypoxia-induced nuclear translocation of YAP and suppress mRNA levels of YAP target genes both in vivo and in vitro. Combined treatment of statins with sorafenib greatly rescued the loss of anti-proliferative effects of sorafenib under hypoxia and improved the inhibitory effects on HepG2 xenograft tumour growth, accompanied by enhanced apoptosis as evidenced by the increased sub-G1 population and PARP cleavage. The expression levels of YAP and its target genes were highly correlated with poor prognosis and predicted a high risk of HCC patients. These findings collectively suggest that statins utilization maybe a promising new strategy to counteract hypoxia-mediated resistance to sorafenib in HCC patients. PMID:27476430

  11. Selective use of sorafenib in the treatment of thyroid cancer

    PubMed Central

    Pitoia, Fabián; Jerkovich, Fernando

    2016-01-01

    Sorafenib is a multiple kinase inhibitor (MKI) approved for the treatment of primary advanced renal cell carcinoma and advanced primary liver cancer. It was recently approved by several health agencies around the world as the first available MKI treatment for radioactive iodine-refractory advanced and progressive differentiated thyroid cancer. Sorafenib targets C-RAF, B-RAF, VEGF receptor-1, -2, -3, PDGF receptor-β, RET, c-kit, and Flt-3. As a multifunctional inhibitor, sorafenib has the potential of inhibiting tumor growth, progression, metastasis, and angiogenesis and downregulating mechanisms that protect tumors from apoptosis and has shown to increase the progression-free survival in several Phase II trials. This led to the Phase III trial (DECISION) which showed that there was an improvement in progression-free survival of 5 months for patients on sorafenib when compared to those on placebo. Adverse events with this drug are common but usually manageable. The development of resistance after 1 or 2 years is almost a rule in most patients who showed partial response or stabilization of the disease while on sorafenib, which makes it necessary to think of a plan for subsequent therapies. These may include the use of another MKI, such as lenvatinib, the second approved MKI for advanced differentiated thyroid cancer, or include patients in clinical trials or the off-label use of other MKIs. Given sorafenib’s earlier approval, most centers now have access to its prescription. The goal of this review was to improve the care of these patients by describing key aspects that all prescribers will need to master in order to optimize outcomes. PMID:27042004

  12. Sorafenib Sensitizes Glioma Cells to the BH3 Mimetic ABT-737 by Targeting MCL1 in a STAT3-Dependent Manner12

    PubMed Central

    Kiprianova, Irina; Remy, Janina; Milosch, Nelli; Mohrenz, Isabelle V.; Seifert, Volker; Aigner, Achim; Kögel, Donat

    2015-01-01

    The oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) is overactivated in malignant glioma and plays a key role in promoting cell survival, thereby increasing the acquired apoptosis resistance of these tumors. Here we investigated the STAT3/myeloid cell leukemia 1 (MCL1) signaling pathway as a target to overcome the resistance of glioma cells to the Bcl-2-inhibiting synthetic BH3 mimetic ABT-737. Stable lentiviral knockdown of MCL1 sensitized LN229 and U87 glioma cells to apoptotic cell death induced by single-agent treatment with ABT-737 which was associated with an early activation of DEVDase activity, cytochrome c release, and nuclear apoptosis. Similar sensitizing effects were observed when ABT-737 treatment was combined with the multikinase inhibitor sorafenib which effectively suppressed levels of phosphorylated STAT3 and MCL1 in MCL1-proficient LN229 and U87 glioma cells. In analogous fashion, these synergistic effects were observed when we combined ABT-737 with the STAT3 inhibitor WP-1066. Lentiviral knockdown of the activating transcription factor 5 combined with subsequent quantitative polymerase chain reaction analysis revealed that sorafenib-dependent suppression of MCL1 occurred at the transcriptional level but did not depend on activating transcription factor 5 which previously had been proposed to be essential for MCL1-dependent glioma cell survival. In contrast, the constitutively active STAT3 mutant STAT3-C was able to significantly enhance MCL1 levels under sorafenib treatment to retain cell survival. Collectively, these data demonstrate that sorafenib targets MCL1 in a STAT3-dependent manner, thereby sensitizing glioma cells to treatment with ABT-737. They also suggest that targeting STAT3 in combination with inducers of the intrinsic pathway of apoptosis may be a promising novel strategy for the treatment of malignant glioma. PMID:26297434

  13. Pediatric phase I trial of oral sorafenib and topotecan in refractory or recurrent pediatric solid malignancies.

    PubMed

    Reed, Damon R; Mascarenhas, Leo; Manning, Kathleen; Hale, Gregory A; Goldberg, John; Gill, Jonathan; Sandler, Eric; Isakoff, Michael S; Smith, Tiffany; Caracciolo, Jamie; Lush, Richard M; Juan, Tzu-Hua; Lee, Jae K; Neuger, Anthony M; Sullivan, Daniel M

    2016-02-01

    Targeted kinase inhibitors and camptothecins have shown preclinical and clinical activity in several cancers. This trial evaluated the maximum tolerated dose (MTD) and dose-limiting toxicities of sorafenib and topotecan administered orally in pediatric patients with relapsed solid tumors. Sorafenib was administered twice daily and topotecan once daily on days 1-5 and 8-12 of each 28-day course. The study utilized a standard 3 + 3 dose escalation design. Three dose levels (DL) were evaluated: (1) sorafenib 150 mg/m(2) and topotecan 1 mg/m(2) ; (2) sorafenib 150 mg/m(2) and topotecan 1.4 mg/m(2) ; and (3) sorafenib 200 mg/m(2) and topotecan 1.4 mg/m(2) . Pharmacokinetics were ascertained and treatment response assessed. Thirteen patients were enrolled. DL2 was the determined MTD. Grade 4 thrombocytopenia delaying therapy for >7 days was observed in one of six patients on DL2, and grade 4 neutropenia that delayed therapy in two of three patients on DL3. A patient with preexisting cardiac failure controlled with medication developed a transient drop in the left ventricular ejection fraction that improved when sorafenib was withheld. Sorafenib exposure with or without topotecan was comparable, and the concentration-time profiles for topotecan alone and in combination with sorafenib were similar. One objective response was noted in a patient with fibromatosis. We determined MTD to be sorafenib 150 mg/m(2) twice daily orally on days 1-28 combined with topotecan 1.4 mg/m(2) once daily on days 1-5 and 8-12. While these doses are 1 DL below the MTD of the agents individually, pharmacokinetic studies suggested adequate drug exposure without drug interactions. The combination had limited activity in the population studied. PMID:26714427

  14. Sorafenib in breast cancer treatment: A systematic review and overview of clinical trials

    PubMed Central

    Zafrakas, Menelaos; Papasozomenou, Panayiota; Emmanouilides, Christos

    2016-01-01

    AIM To evaluate the current role of sorafenib, an oral multikinase inhibitor in the treatment of breast cancer. METHODS An extensive search of the literature until March 2016 was carried out in Medline and clinicaltrials.gov, by using the search terms “sorafenib” and “breast cancer”. Papers found were checked for further relevant publications. Overall, 21 relevant studies were found, 18 in advanced breast cancer (16 in stage IV and two in stages III-IV) and three in early breast cancer. RESULTS Among studies in advanced breast cancer, there were two trials with sorafenib as monotherapy, four trials of sorafenib in combination with taxanes, two in combination with capecitabine, one with gemcitabine and/or capecitabine, one with vinorelbine, one with bevacizumab, one with pemetrexed and one with ixabepilone, three trials of sorafenib in combination with endocrine therapy and two trials in women with brain metastases undergoing whole brain radiotherapy. In addition, there was one trial of sorafenib added to standard chemotherapy in the adjuvant setting, and two trials in the neoadjuvant setting. In general, sorafenib was well tolerated in breast cancer patients, though its dosage had to be adjusted in some trials, and discontinuation rates were high, particularly for the combination of sorafenib with anastrozole. Sorafenib monotherapy and combinations with taxanes, bevacizumab and ixabepilone showed inadequate efficacy, while efficacy results from combinations with gemcitabine and/or capecitabine and possibly tamoxifen were more promising. CONCLUSION At present, sorafenib should not be used for the treatment of breast cancer outside of clinical trials and more clinical data are needed in order to support its standard use in breast cancer therapy. PMID:27579253

  15. [Three Patients with Acute Myocardial Infarction Associated with Targeted Therapy of Sorafenib for Metastatic Renal Cell Carcinoma : Case Report].

    PubMed

    Takagi, Kimiaki; Takai, Manabu; Kawata, Kei; Horie, Kengo; Kikuchi, Mina; Kato, Taku; Mizutani, Kosuke; Seike, Kensaku; Tsuchiya, Tomohiro; Yasuda, Mitsuru; Yokoi, Shigeaki; Nakano, Masahiro; Ushikoshi, Hiroaki; Miyazaki, Tatsuhiko; Deguchi, Takashi

    2015-09-01

    Sorafenib is a tyrosine kinase inhibitor (TKI) of the vascular endothelial growth factor receptor (VEGFR) used for advanced renal cell carcinoma. Treatment with sorafenib prolongs progression-free survival in patients with advanced clear-cell renal cell carcinoma. However, in spite of its therapeutic efficacy, sorafenib causes a wide range of adverse events. Cardiovascular adverse events have been observed when sorafenib was used with targeted agents. Although these adverse events like hypertension, reduced left ventricular ejection fraction, cardiac ischemia or infarction were manageable with standard medical therapies in most cases, some had a poor clinical outcome. We report three cases of acute myocardial infarction associated with sorafenib in patients with metastatic renal cell carcinoma. PMID:26497860

  16. Dipeptidyl peptidase-4 inhibitor for steroid-induced diabetes

    PubMed Central

    Yanai, Hidekatsu; Masui, Yoshinori; Yoshikawa, Reo; Kunimatsu, Junwa; Kaneko, Hiroshi

    2010-01-01

    The addition of the dipeptidyl peptidase-4 (DDP-4) inhibitor has been reported to achieve greater improvements in glucose metabolism with fewer adverse events compared to increasing the metformin dose in type 2 diabetic patients. We present a patient with steroid-induced diabetes whose blood glucose levels were ameliorated by the use of the DPP-4 inhibitor, showing that the DPP-4 inhibitors may be an effective and safe oral anti-diabetic drug for steroid-induced diabetes. PMID:21537433

  17. Synergistic Inhibitory Effect of Hyperbaric Oxygen Combined with Sorafenib on Hepatoma Cells

    PubMed Central

    Peng, Hai-Shan; Liao, Ming-Bin; Zhang, Mei-Yin; Xie, Yin; Xu, Li; Zhang, Yao-Jun; Zheng, X. F. Steven; Wang, Hui-Yun; Chen, Yi-Fei

    2014-01-01

    Objectives Hypoxia is a common phenomenon in solid tumors, associated with chemotherapy and radiotherapy resistance, recurrence and metastasis. Hyperbaric oxygen (HBO) therapy can increase tissue oxygen pressure and content to prevent the resistance, recurrence and metastasis of cancer. Presently, Sorafenib is a first-line drug, targeted for hepatocellular carcinoma (HCC) but effective in only a small portion of patients and can induce hypoxia. The purpose of this study is to investigate the effect of HBO in combination with sorafenib on hepatoma cells. Methods Hepatoma cell lines (BEL-7402 and SK-Hep1) were treated with HBO at 2 atmosphere absolute pressure for 80 min per day or combined with sorafenib or cisplatin. At different time points, cells were tested for cell growth, colony formation, apoptosis, cell cycle and migration. Finally, miRNA from the hepatoma cells was detected by microRNA array and validated by qRT-PCR. Results Although HBO, sorafenib or cisplatin alone could inhibit growth of hepatoma cells, HBO combined with sorafenib or cisplatin resulted in much greater synergistic growth inhibition (cell proliferation and colony formation) in hepatoma cells. Similarly, the synergistic effect of HBO and sorafenib on induction of apoptosis was also observed in hepatoma cells. HBO induced G1 arrest in SK-Hep1 not in BEL-7402 cells, but enhanced cell cycle arrest induced by sorafenib in BEL-7402 treated cells. However, HBO had no obvious effect on the migration of hepatoma cells, and microRNA array analysis showed that hepatoma cells with HBO treatment had significantly different microRNA expression profiles from those with blank control. Conclusions We show for the first time that HBO combined with sorafenib results in synergistic growth inhibition and apoptosis in hepatoma cells, suggesting a potential application of HBO combined with sorafenib in HCC patients. Additionally, we also show that HBO significantly altered microRNA expression in hepatoma cells

  18. Sorafenib in advanced melanoma: a Phase II randomised discontinuation trial analysis.

    PubMed

    Eisen, T; Ahmad, T; Flaherty, K T; Gore, M; Kaye, S; Marais, R; Gibbens, I; Hackett, S; James, M; Schuchter, L M; Nathanson, K L; Xia, C; Simantov, R; Schwartz, B; Poulin-Costello, M; O'Dwyer, P J; Ratain, M J

    2006-09-01

    The effects of sorafenib--an oral multikinase inhibitor targeting the tumour and tumour vasculature--were evaluated in patients with advanced melanoma enrolled in a large multidisease Phase II randomised discontinuation trial (RDT). Enrolled patients received a 12-week run-in of sorafenib 400 mg twice daily (b.i.d.). Patients with changes in bi-dimensional tumour measurements <25% from baseline were then randomised to sorafenib or placebo for a further 12 weeks (ie to week 24). Patients with > or =25% tumour shrinkage after the run-in continued on open-label sorafenib, whereas those with > or =25% tumour growth discontinued treatment. This analysis focussed on secondary RDT end points: changes in bi-dimensional tumour measurements from baseline after 12 weeks and overall tumour responses (WHO criteria) at week 24, progression-free survival (PFS), safety and biomarkers (BRAF, KRAS and NRAS mutational status). Of 37 melanoma patients treated during the run-in phase, 34 were evaluable for response: one had > or =25% tumour shrinkage and remained on open-label sorafenib; six (16%) had <25% tumour growth and were randomised (placebo, n=3; sorafenib, n=3); and 27 had > or =25% tumour growth and discontinued. All three randomised sorafenib patients progressed by week 24; one remained on sorafenib for symptomatic relief. All three placebo patients progressed by week-24 and were re-started on sorafenib; one experienced disease re-stabilisation. Overall, the confirmed best responses for each of the 37 melanoma patients who received sorafenib were 19% stable disease (SD) (ie n=1 open-label; n=6 randomised), 62% (n=23) progressive disease (PD) and 19% (n=7) unevaluable. The overall median PFS was 11 weeks. The six randomised patients with SD had overall PFS values ranging from 16 to 34 weeks. The most common drug-related adverse events were dermatological (eg rash/desquamation, 51%; hand-foot skin reaction, 35%). There was no relationship between V600E BRAF status and disease

  19. Variability of Sorafenib Toxicity and Exposure over Time: A Pharmacokinetic/Pharmacodynamic Analysis

    PubMed Central

    Ropert, Stanislas; Mir, Olivier; Coriat, Romain; Billemont, Bertrand; Tod, Michel; Cabanes, Laure; Franck, Nathalie; Blanchet, Benoit; Goldwasser, François

    2012-01-01

    Background. Sorafenib displays major interpatient pharmacokinetic variability. It is unknown whether the pharmacokinetics of sorafenib influence its toxicity. Methods. We analyzed the severity and kinetics of sorafenib-induced toxicities in unselected consecutive patients with cancer, as well as their relationship with biological, clinical, and pharmacokinetic parameters. Toxicity was recorded bimonthly. Sorafenib plasma concentrations were assessed by liquid chromatography. Results. For 83 patients (median age, 62 years; range, 21–84 years), median sorafenib 12-hour area under the curve (AUC0–12) was 52.8 mg · h/L (range: 11.8–199.6). A total of 51 patients (61%) experienced grade 3–4 toxicities, including hand-foot skin reactions (23%), asthenia (18%), and diarrhea (11%). Sorafenib AUC0–12 preceding grade 3–4 toxicities was significantly higher than that observed in the remaining population (61.9 mg · h/L vs. 53 mg · h/L). In 25 patients treated with fixed doses of sorafenib for the first 4 months, median dose-normalized AUC0–12 on day 120 was significantly lower than on day 15 (63 vs. 102 mg · h/L). The incidence of hypertension and hand-foot skin reactions significantly decreased over time. Conclusion. Sorafenib AUC0–12 decreases over time, similarly to the incidence of hypertension and hand-foot skin reactions. Monitoring of sorafenib plasma concentrations may help to prevent acute severe toxicities and detect patients with suboptimal exposure at disease progression. PMID:22752067

  20. The effect of sorafenib on liver regeneration and angiogenesis after partial hepatectomy in rats

    PubMed Central

    Kiroplastis, K; Fouzas, I; Katsiki, E; Patsiaoura, K; Daoudaki, M; Komninou, A; Xolongitas, E; Katsika, E; Kaidoglou, K; Papanikolaou, V

    2015-01-01

    Background Liver regeneration is vital for the survival of patients submitted to extensive liver resection as a treatment of hepatocellular carcinoma (HCC). Sorafenib is a multikinase inhibitor of angiogenesis and cell division, both of which are integral components of liver regeneration. We investigated the effect of preoperative treatment with sorafenib, a drug used for the treatment of HCC, on liver regeneration and angiogenesis in healthy rats, after two-thirds partial hepatectomy (PH2/3). Methods In total 48 Wistar rats received intragastric injections of sorafenib (30 mg/kg/d) or vehicle, underwent PH2/3, and were sacrificed at 48, 96 or 168 hours after that. The regenerative index of the liver remnant was studied, as well as the mitotic index. DNA synthesis and angiogenesis were estimated by immunohistochemistry for the Ki-67 and CD34 antigens, respectively. Results Sorafenib reduced significantly the regenerative index at all time points but not the mitotic index at 48, 96 or 168 hours. Deoxyribonucleic acid (DNA) synthesis and angiogenesis were not affected significantly either. Conclusions Sorafenib, when administered preoperatively, reduces incompletely and transiently the regeneration of the liver after PH2/3 in rats. This could mean that sorafenib can be used as neoadjuvant treatment of patients with HCC prior to liver resection, but further experimental and clinical studies are needed to establish the safety of this treatment. Hippokratia 2015; 19 (3): 249-255. PMID:27418785

  1. Molecular Mechanism and Prediction of Sorafenib Chemoresistance in Human Hepatocellular Carcinoma.

    PubMed

    Nishida, Naoshi; Kitano, Masayuki; Sakurai, Toshiharu; Kudo, Masatoshi

    2015-10-01

    Hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide, and prognosis remains unsatisfactory when the disease is diagnosed at an advanced stage. Many molecular targeted agents are being developed for the treatment of advanced HCC; however, the only promising drug to have been developed is sorafenib, which acts as a multi-kinase inhibitor. Unfortunately, a subgroup of HCC is resistant to sorafenib, and the majority of these HCC patients show disease progression even after an initial satisfactory response. To date, a number of studies have examined the underlying mechanisms involved in the response to sorafenib, and trials have been performed to overcome the acquisition of drug resistance. The anti-tumor activity of sorafenib is largely attributed to the blockade of the signals from growth factors, such as vascular endothelial growth factor receptor and platelet-derived growth factor receptor, and the downstream RAF/mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK cascade. The activation of an escape pathway from RAF/MEK/ERK possibly results in chemoresistance. In addition, there are several features of HCCs indicating sorafenib resistance, such as epithelial-mesenchymal transition and positive stem cell markers. Here, we review the recent reports and focus on the mechanism and prediction of chemoresistance to sorafenib in HCC. PMID:26488287

  2. Sorafenib: a review of its use in patients with radioactive iodine-refractory, metastatic differentiated thyroid carcinoma.

    PubMed

    Blair, Hannah A; Plosker, Greg L

    2015-03-01

    Sorafenib (Nexavar®) is the first tyrosine kinase inhibitor to be approved for the treatment of radioactive iodine (RAI)-refractory differentiated thyroid carcinoma (DTC). In the pivotal phase III DECISION trial in patients with RAI-refractory, locally advanced or metastatic DTC, oral sorafenib 400 mg twice daily significantly prolonged median progression-free survival (PFS) relative to placebo. The PFS benefit of sorafenib over placebo was evident in all pre-specified clinical and genetic biomarker subgroups, and neither BRAF nor RAS mutation status was predictive of sorafenib benefit for PFS. The objective response rate was significantly higher in patients receiving sorafenib than in those receiving placebo; all objective responses were partial responses. The overall survival benefit of sorafenib is as yet unclear, with no significant benefit observed at the time of primary analysis or at 9 months following the primary analysis. Overall survival was possibly confounded by the crossover of patients in the placebo group to sorafenib upon disease progression. The adverse events associated with sorafenib in the DECISION trial were consistent with the known tolerability profile of the drug, with hand-foot skin reaction, diarrhea, and alopecia reported most commonly. Most treatment-emergent adverse events were grade 1 or 2 in severity and occurred early in treatment. However, a high proportion of patients discontinued sorafenib therapy or required dose reductions or interruptions because of toxicity. Although final overall survival data are awaited, current evidence suggests that sorafenib is a promising new treatment option for patients with RAI-refractory, metastatic DTC. PMID:25742918

  3. Bufalin Reverses Resistance to Sorafenib by Inhibiting Akt Activation in Hepatocellular Carcinoma: The Role of Endoplasmic Reticulum Stress.

    PubMed

    Zhai, Bo; Hu, Fengli; Yan, Haijiang; Zhao, Dali; Jin, Xin; Fang, Taishi; Pan, Shangha; Sun, Xueying; Xu, Lishan

    2015-01-01

    Sorafenib is the standard first-line therapeutic treatment for patients with advanced hepatocellular carcinoma (HCC), but its use is hampered by the development of drug resistance. The activation of Akt by sorafenib is thought to be responsible for this resistance. Bufalin is the major active ingredient of the traditional Chinese medicine Chan su, which inhibits Akt activation; therefore, Chan su is currently used in the clinic to treat cancer. The present study aimed to investigate the ability of bufalin to reverse both inherent and acquired resistance to sorafenib. Bufalin synergized with sorafenib to inhibit tumor cell proliferation and induce apoptosis. This effect was at least partially due to the ability of bufalin to inhibit Akt activation by sorafenib. Moreover, the ability of bufalin to inactivate Akt depended on endoplasmic reticulum (ER) stress mediated by inositol-requiring enzyme 1 (IRE1). Silencing IRE1 with siRNA blocked the bufalin-induced Akt inactivation, but silencing eukaryotic initiation factor 2 (eIF2) or C/EBP-homologous protein (CHOP) did not have the same effect. Additionally, silencing Akt did not influence IRE1, CHOP or phosphorylated eIF2α expression. Two sorafenib-resistant HCC cell lines, which were established from human HCC HepG2 and Huh7 cells, were refractory to sorafenib-induced growth inhibition but were sensitive to bufalin. Thus, Bufalin reversed acquired resistance to sorafenib by downregulating phosphorylated Akt in an ER-stress-dependent manner via the IRE1 pathway. These findings warrant further studies to examine the utility of bufalin alone or in combination with sorafenib as a first- or second-line treatment after sorafenib failure for advanced HCC. PMID:26381511

  4. Bufalin Reverses Resistance to Sorafenib by Inhibiting Akt Activation in Hepatocellular Carcinoma: The Role of Endoplasmic Reticulum Stress

    PubMed Central

    Zhai, Bo; Hu, Fengli; Yan, Haijiang; Zhao, Dali; Jin, Xin; Fang, Taishi; Pan, Shangha; Sun, Xueying; Xu, Lishan

    2015-01-01

    Sorafenib is the standard first-line therapeutic treatment for patients with advanced hepatocellular carcinoma (HCC), but its use is hampered by the development of drug resistance. The activation of Akt by sorafenib is thought to be responsible for this resistance. Bufalin is the major active ingredient of the traditional Chinese medicine Chan su, which inhibits Akt activation; therefore, Chan su is currently used in the clinic to treat cancer. The present study aimed to investigate the ability of bufalin to reverse both inherent and acquired resistance to sorafenib. Bufalin synergized with sorafenib to inhibit tumor cell proliferation and induce apoptosis. This effect was at least partially due to the ability of bufalin to inhibit Akt activation by sorafenib. Moreover, the ability of bufalin to inactivate Akt depended on endoplasmic reticulum (ER) stress mediated by inositol-requiring enzyme 1 (IRE1). Silencing IRE1 with siRNA blocked the bufalin-induced Akt inactivation, but silencing eukaryotic initiation factor 2 (eIF2) or C/EBP-homologous protein (CHOP) did not have the same effect. Additionally, silencing Akt did not influence IRE1, CHOP or phosphorylated eIF2α expression. Two sorafenib-resistant HCC cell lines, which were established from human HCC HepG2 and Huh7 cells, were refractory to sorafenib-induced growth inhibition but were sensitive to bufalin. Thus, Bufalin reversed acquired resistance to sorafenib by downregulating phosphorylated Akt in an ER-stress-dependent manner via the IRE1 pathway. These findings warrant further studies to examine the utility of bufalin alone or in combination with sorafenib as a first- or second-line treatment after sorafenib failure for advanced HCC. PMID:26381511

  5. Alpha-fetoprotein is a biomarker of unfolded protein response and altered proteostasis in hepatocellular carcinoma cells exposed to sorafenib.

    PubMed

    Houessinon, Aline; Gicquel, Albane; Bochereau, Flora; Louandre, Christophe; Nyga, Rémy; Godin, Corinne; Degonville, James; Fournier, Emma; Saidak, Zuzana; Drullion, Claire; Barbare, Jean-Claude; Chauffert, Bruno; François, Catherine; Pluquet, Olivier; Galmiche, Antoine

    2016-01-28

    Sorafenib is the treatment of reference for advanced hepatocellular carcinoma (HCC). A decrease in the serum levels of Alpha-fetoprotein (AFP) is reported to be the biological parameter that is best associated with disease control by sorafenib. In order to provide a biological rationale for the variations of AFP, we analyzed the various steps of AFP production in human HCC cell lines exposed to sorafenib. Sorafenib dramatically reduced the levels of AFP produced by HCC cells independently of its effect on cell viability. The mRNA levels of AFP decreased upon sorafenib treatment, while the AFP protein remained localized in the Golgi apparatus. Sorafenib activated the Regulated Inositol-Requiring Enzyme-1α (IRE-1α) and the PKR-like ER Kinase (PERK)-dependent arms of the Unfolded Protein Response (UPR). The inhibition of IRE-1α partially restored the mRNA levels of AFP upon treatment with sorafenib. The inhibition of both pathways partially prevented the drop in the production of AFP induced by sorafenib. The findings provide new insights on the regulation of AFP, and identify it as a biomarker suitable for the exploration of HCC cell proteostasis in the context of therapeutic targeting. PMID:26546044

  6. Sorafenib and sunitinib: novel targeted therapies for renal cell cancer.

    PubMed

    Grandinetti, Cheryl A; Goldspiel, Barry R

    2007-08-01

    Renal cell cancer (RCC) is a relatively uncommon malignancy, with 51,190 cases expected to be diagnosed in 2007. Localized disease is curable by surgery; however, locally advanced or metastatic disease is not curable in most cases and, until recently, had a limited response to drug treatment. Historically, biologic response modifiers or immunomodulating agents were tested in clinical trials based on observations that some cases of RCC can spontaneously regress. High-dose aldesleukin is approved by the United States Food and Drug Administration as a treatment for advanced RCC; however, the drug is associated with a high frequency of severe adverse effects. Responses have been observed with low-dose aldesleukin and interferon alfa, but with little effect on overall survival. Sorafenib and sunitinib are novel therapies that target growth factor receptors known to be activated by the hypoxia-inducible factor and the Ras-Raf/MEK/ERK pathways. These pathways are important in the pathophysiology of RCC. Sorafenib and sunitinib have shown antitumor activity as first- and second-line therapy in patients with cytokine-refractory metastatic RCC who have clear-cell histology. Although complete responses are not common, both drugs promote disease stabilization and increase progression-free survival. This information suggests that disease stabilization may be an important determinant for response in RCC and possibly other cancers. Sorafenib and sunitinib are generally well tolerated and are considered first- and second-line treatment options for patients with advanced clear cell RCC. In addition, sorafenib and sunitinib have shown promising results in initial clinical trials evaluating antitumor activity in patients who are refractory to other antiangiogenic therapy. The most common toxicities with both sorafenib and sunitinib are hand-foot syndrome, rash, fatigue, hypertension, and diarrhea. Research is directed toward defining the optimal use of these new agents. PMID:17655513

  7. Sorafenib/Regorafenib and Lapatinib interact to kill CNS tumor cells

    PubMed Central

    Hamed, Hossein A.; Tavallai, Seyedmehrad; Grant, Steven; Poklepovic, Andrew; Dent, Paul

    2014-01-01

    The present studies were to determine whether the multi-kinase inhibitor sorafenib or its derivative regorafenib interacted with the ERBB1/ERBB2 inhibitor lapatinib to kill CNS tumor cells. In multiple CNS tumor cell types sorafenib and lapatinib interacted in a greater than additive fashion to cause tumor cell death. Tumor cells lacking PTEN, and anoikis or lapatinib resistant cells were as sensitive to the drug combination as cells expressing PTEN or parental cells, respectively. Similar data were obtained using regorafenib. Treatment of brain cancer cells with [sorafenib + lapatinib] enhanced radiation toxicity. The drug combination increased the numbers of LC3-GFP vesicles; this correlated with a reduction in endogenous LC3II, and p62 and LAMP2 degradation. Knock down of Beclin1 or ATG5 significantly suppressed drug combination lethality. Expression of c-FLIP-s, BCL-XL or dominant negative caspase 9 reduced drug combination toxicity; knock down of FADD or CD95 was protective. Expression of both activated AKT and activated MEK1 or activated mTOR was required to strongly suppress drug combination lethality. As both lapatinib and sorafenib are FDA approved agents, our data argue for further determination as to whether lapatinib and sorafenib is a useful glioblastoma therapy. PMID:24911215

  8. Poly(lactide-co-glycolide) microspheres for MRI-monitored transcatheter delivery of sorafenib to liver tumors.

    PubMed

    Chen, Jeane; Sheu, Alexander Y; Li, Weiguo; Zhang, Zhuoli; Kim, Dong-Hyun; Lewandowski, Robert J; Omary, Reed A; Shea, Lonnie D; Larson, Andrew C

    2014-06-28

    The multi-kinase inhibitor (MKI) sorafenib can be an effective palliative therapy for patients with hepatocellular carcinoma (HCC). However, patient tolerance is often poor due to common systemic side effects following oral administration. Local transcatheter delivery of sorafenib to liver tumors has the potential to reduce systemic toxicities while increasing the dose delivered to targeted tumors. We developed sorafenib-eluting PLG microspheres for delivery by intra-hepatic transcatheter infusion in an orthotropic rodent HCC model. The particles also encapsulated iron-oxide nanoparticles permitting magnetic resonance imaging (MRI) of intra-hepatic biodistributions. The PLG microspheres (diameter≈1μm) were loaded with 18.6% (w/w) sorafenib and 0.54% (w/w) ferrofluid and 65.2% of the sorafenib was released within 72h of media exposure. In vitro studies demonstrated significant reductions in HCC cell proliferation with increasing doses of the sorafenib-eluting microspheres, where the estimated IC50 was a 29μg/mL dose of microspheres. During in vivo studies, MRI permitted intra-procedural visualization of intra-hepatic microsphere delivery. At 72h after microsphere infusion, microvessel density was significantly reduced in tumors treated with the sorafenib-eluting microspheres compared to both sham control tumors (by 35%) and controls (by 30%). These PLG microspheres offer the potential to increase the efficacy of molecularly targeted MKI therapies while reducing systemic exposures via selective catheter-directed delivery to HCC. PMID:24727059

  9. A polymeric nanoparticle formulation of curcumin in combination with sorafenib synergistically inhibits tumor growth and metastasis in an orthotopic model of human hepatocellular carcinoma.

    PubMed

    Hu, Bo; Sun, Ding; Sun, Chao; Sun, Yun-Fan; Sun, Hai-Xiang; Zhu, Qing-Feng; Yang, Xin-Rong; Gao, Ya-Bo; Tang, Wei-Guo; Fan, Jia; Maitra, Anirban; Anders, Robert A; Xu, Yang

    2015-12-25

    Curcumin, a yellow polyphenol extracted from the rhizome of turmeric root (Curcuma longa) has potent anti-cancer properties in many types of tumors with ability to reverse multidrug resistance of cancer cells. However, widespread clinical application of this agent in cancer and other diseases has been limited due to its poor aqueous solubility. The recent findings of polymeric nanoparticle formulation of curcumin (NFC) have shown the potential for circumventing the problem of poor solubility, however evidences for NFC's anti-cancer and reverse multidrug resistance properties are lacking. Here we provide models of human hepatocellular carcinoma (HCC), the most common form of primary liver cancer, in vitro and in vivo to evaluate the efficacy of NFC alone and in combination with sorafenib, a kinase inhibitor approved for treatment of HCC. Results showed that NFC not only inhibited the proliferation and invasion of HCC cell lines in vitro, but also drastically suppressed primary tumor growth and lung metastases in vivo. Moreover, in combination with sorafenib, NFC induced HCC cell apoptosis and cell cycle arrest. Mechanistically, NFC and sorafenib synergistically down-regulated the expression of MMP9 via NF-κB/p65 signaling pathway. Furthermore, the combination therapy significantly decreased the population of CD133-positive HCC cells, which have been reported as cancer initiating cells in HCC. Taken together, NanoCurcumin provides an opportunity to expand the clinical repertoire of this agent. Additional studies utilizing a combination of NanoCurcumin and sorafenib in HCC are needed for further clinical development. PMID:26482853

  10. Synergistic Effect of Sorafenib and Radiation on Human Oral Carcinoma in vivo.

    PubMed

    Hsu, Fei-Ting; Chang, Betty; Chen, John Chun-Hao; Chiang, I-Tsang; Liu, Yu-Chang; Kwang, Wei-Kang; Hwang, Jeng-Jong

    2015-01-01

    Oral squamous cell carcinoma often causes bone invasion resulting in poor prognosis and affects the quality of life for patients. Herein, we combined radiation with sorafenib, to evaluate the combination effect on tumor progression and bone erosion in an in situ human OSCC-bearing mouse model. Treatment procedure were arranged as following groups: (a) normal (no tumor); (b) control (with tumor); (c) sorafenib (10 mg/kg/day); (d) radiation (single dose of 6 Gy); (e) pretreatment (sorafenib treatment for 3 days prior to radiation), and (f) concurrent treatment (sorafenib and radiation on the same day). The inhibition of tumor growth and expression level of p65 of NF-κB in tumor tissues were the most significant in the pretreatment group. EMSA and Western blot showed that DNA/NF-κB activity and the expressions of NF-κB-associated proteins were down-regulated. Notably, little to no damage in mandibles and zygomas of mice treated with combination of sorafenib and radiation was found by micro-CT imaging. In conclusion, sorafenib combined with radiation suppresses radiation-induced NF-κB activity and its downstream proteins, which contribute to radioresistance and tumorigenesis. Additionally, bone destruction is also diminished, suggesting that combination treatment could be a potential strategy against human OSCC. PMID:26487364

  11. Synergistic Effect of Sorafenib and Radiation on Human Oral Carcinoma in vivo

    PubMed Central

    Hsu, Fei-Ting; Chang, Betty; Chen, John Chun-Hao; Chiang, I-Tsang; Liu, Yu-Chang; Kwang, Wei-Kang; Hwang, Jeng-Jong

    2015-01-01

    Oral squamous cell carcinoma often causes bone invasion resulting in poor prognosis and affects the quality of life for patients. Herein, we combined radiation with sorafenib, to evaluate the combination effect on tumor progression and bone erosion in an in situ human OSCC-bearing mouse model. Treatment procedure were arranged as following groups: (a) normal (no tumor); (b) control (with tumor); (c) sorafenib (10 mg/kg/day); (d) radiation (single dose of 6 Gy); (e) pretreatment (sorafenib treatment for 3 days prior to radiation), and (f) concurrent treatment (sorafenib and radiation on the same day). The inhibition of tumor growth and expression level of p65 of NF-κB in tumor tissues were the most significant in the pretreatment group. EMSA and Western blot showed that DNA/NF-κB activity and the expressions of NF-κB-associated proteins were down-regulated. Notably, little to no damage in mandibles and zygomas of mice treated with combination of sorafenib and radiation was found by micro-CT imaging. In conclusion, sorafenib combined with radiation suppresses radiation-induced NF-κB activity and its downstream proteins, which contribute to radioresistance and tumorigenesis. Additionally, bone destruction is also diminished, suggesting that combination treatment could be a potential strategy against human OSCC. PMID:26487364

  12. [BRAF Inhibitor-Induced Erythema Nodosum-Like Lesions].

    PubMed

    Shiba, Keiko; Moriuchi, Reine; Morita, Yusuke; Nakamura, Michio; Takigami, Masayoshi; Shimizu, Satoko

    2016-05-01

    BRAF inhibitors have been licensed for the treatment of unresectable or metastatic BRAF-mutated melanomas. In Japan, the BRAF inhibitor vemurafenib has been available since December 2014. Several adverse events induced by BRAF inhibitors have been reported, such as Stevens-Johnson syndrome, toxic epidermal necrosis, squamous cell carcinoma, secondary melanoma, and hand-foot syndrome. Recently, inflammatory skin lesions clinically resembling erythema nodosum have been reported as side effects that may lead to treatment discontinuation. In this report, we described the first Japanese case of erythema nodosum-like lesions induced by vemurafenib and discussed the countermeasures to this adverse reaction. Dose reduction or interruption of BRAF inhibitors should be considered on a case-by-case basis because the condition may resolve spontaneously or under symptomatic treatment. We postulate that erythema nodosum-like lesions can be controlled by careful follow-up and supportive care. PMID:27210102

  13. Growth arrest DNA damage-inducible gene 45 gamma expression as a prognostic and predictive biomarker in hepatocellular carcinoma

    PubMed Central

    Ou, Da-Liang; Shyue, Song-Kun; Lin, Liang-In; Feng, Zi-Rui; Liou, Jun-Yang; Fan, Hsiang-Hsuan; Lee, Bin-Shyun; Hsu, Chiun; Cheng, Ann-Lii

    2015-01-01

    Growth arrest DNA damage-inducible gene 45 (GADD45) family proteins play a crucial role in regulating cellular stress responses and apoptosis. The present study explored the prognostic and predictive role of GADD45γ in hepatocellular carcinoma (HCC) treatment. GADD45γ expression in HCC cells was examined using quantitative reverse transcription-PCR (qRT-PCR) and Western blotting. The control of GADD45γ transcription was examined using a luciferase reporter assay and chromatin immunoprecipitation. The in vivo induction of GADD45γ was performed using adenoviral transfer. The expression of GADD45γ in HCC tumor tissues from patients who had undergone curative resection was measured using qRT-PCR. Sorafenib induced expression of GADD45γ mRNA and protein, independent of its RAF kinase inhibitor activity. GADD45γ induction was more prominent in sorafenib-sensitive HCC cells (Huh-7 and HepG2, IC50 6–7 μM) than in sorafenib-resistant HCC cells (Hep3B, Huh-7R, and HepG2R, IC50 12–15 μM). Overexpression of GADD45γ reversed sorafenib resistance in vitro and in vivo, whereas GADD45γ expression knockdown by using siRNA partially abrogated the proapoptotic effects of sorafenib on sorafenib-sensitive cells. Overexpression of survivin in HCC cells abolished the antitumor enhancement between GADD45γ overexpression and sorafenib treatment, suggesting that survivin is a crucial mediator of antitumor effects of GADD45γ. GADD45γ expression decreased in tumors from patients with HCC who had undergone curative surgery, and low GADD45γ expression was an independent prognostic factor for poor survival, in addition to old age and vascular invasion. The preceding data indicate that GADD45γ suppression is a poor prognostic factor in patients with HCC and may help predict sorafenib efficacy in HCC. PMID:26172295

  14. Yttrium-90 Radioembolization in Patients with Hepatocellular Carcinoma Who have Previously Received Sorafenib

    PubMed Central

    Rana, Nitesh; Ju, Andrew Wenhua; Bazylewicz, Michael; Kallakury, Bhaskar; He, Aiwu Ruth; Unger, Keith R.; Lee, Justin S.

    2013-01-01

    Purpose: Yttrium-90 radioembolization (RE) is a locoregional therapy option for hepatocellular carcinoma (HCC). Sorafenib is a multikinase inhibitor used in HCC that can potentially affect the efficacy of RE by altering tumor vascularity or suppressing post-irradiation angiogenesis. The safety and efficacy of sorafenib followed by RE has not been previously reported. Materials and Methods: Patients with HCC who received RE after sorafenib were included in this retrospective review. Overall survival, toxicity, and maximal radiographic response and necrosis criteria were examined. Results: Ten patients (15 RE administrations) fit the inclusion criteria. All were Barcelona Clinic Liver Cancer (BCLC) stage C. Median follow-up was 16.5 weeks. Median overall survival and radiographic progression-free survival were 30 and 28 weeks, respectively. Significant differences in overall survival were seen based on Child-Pugh class (p = 0.002) and radiographic response (p = 0.009). Three patients had partial response, six had stable disease, and one had progressive disease. Grade 1 or 2 acute fatigue, anorexia, and abdominal pain were common. Three patients had Grade 3 ascites in the setting of disease progression. Two patients had Grade 3 biochemical toxicity. One patient was sufficiently downstaged following RE and sorafenib to receive a partial hepatectomy. Conclusion: Yttrium-90 RE in patients with HCC who have received sorafenib demonstrate acceptable toxicity and rates of radiographic response. However, the overall survival is lower than that reported in the literature on RE alone or sorafenib alone. This may be due in part to more patients in this study having advanced disease compared to these other study populations. Larger prospective studies are needed to determine whether the combination of RE and sorafenib is superior to either therapy alone. PMID:24416722

  15. pAKT Expression and Response to Sorafenib in Differentiated Thyroid Cancer.

    PubMed

    Yarchoan, Mark; Ma, Changqing; Troxel, Andrea B; Stopenski, Stephen J; Tang, Waixing; Cohen, Aaron B; Pappas-Paxinos, Marina; Johnson, Burles A; Chen, Emerson Y; Feldman, Michael D; Brose, Marcia S

    2016-06-01

    Sorafenib has an antitumor activity in patients with radioactive iodine-refractory differentiated thyroid carcinoma (RAIR-DTC). Prior research has implicated signaling through the MAPK and AKT/PI3K pathways in the progression of DTC. To assess whether the activity of these pathways is predictive of response to sorafenib, we retrospectively studied molecular tumor markers from these two pathways from a phase 2 study of sorafenib in RAIR-DTC. Tumor samples from 40 of 53 DTC subjects obtained prior to initiation of sorafenib were immunostained with DAB-labeled antibodies to phospho-AKT (pAKT), phospho-ERK (pERK), and phospho-S6 (pS6). BRAFV600E genetic mutation analysis was performed on all samples. Expression levels and mutational status were compared to response and progression-free survival (PFS) for each patient. Low tumor expression of nuclear pAKT was associated with partial response to sorafenib (p < 0.01). Patients with nuclear pAKT expression that was below the median for our sample were more than three times as likely to have a partial response as patients with equal to or above median expression. There was no correlation between tumor expression of nuclear pERK or pS6 and response. Endothelial cell and pericyte expression of pERK, pAKT, and pS6 were not predictive of response. There was no correlation between BRAFV600E mutation status and partial response. No correlation was observed between either the expression of pAKT, pERK, or pS6, or the presence of the BRAFV600E mutation, and PFS. In conclusion, lower tumor expression of nuclear pAKT was associated with higher rate of response to sorafenib. This observation justifies evaluation of combination therapy with sorafenib and an inhibitor of the PI3K/AKT signaling pathway in RAIR-DTC. PMID:26994002

  16. In vivo RNAi screening identifies a mechanism of sorafenib resistance in liver cancer

    PubMed Central

    Rudalska, Ramona; Dauch, Daniel; Longerich, Thomas; McJunkin, Katherine; Wuestefeld, Torsten; Kang, Tae-Won; Hohmeyer, Anja; Pesic, Marina; Leibold, Josef; von Thun, Anne; Schirmacher, Peter; Zuber, Johannes; Weiss, Karl-Heinz; Powers, Scott; Malek, Nisar P; Eilers, Martin; Sipos, Bence; Lowe, Scott W; Geffers, Robert; Laufer, Stefan; Zender, Lars

    2015-01-01

    In solid tumors, resistance to therapy inevitably develops upon treatment with cytotoxic drugs or molecularly targeted therapies. Here, we describe a system that enables pooled shRNA screening directly in mouse hepatocellular carcinomas (HCC) in vivo to identify genes likely to be involved in therapy resistance. Using a focused shRNA library targeting genes located within focal genomic amplifications of human HCC, we screened for genes whose inhibition increased the therapeutic efficacy of the multikinase inhibitor sorafenib. Both shRNA-mediated and pharmacological silencing of Mapk14 (p38α) were found to sensitize mouse HCC to sorafenib therapy and prolong survival by abrogating Mapk14-dependent activation of Mek-Erk and Atf2 signaling. Elevated Mapk14-Atf2 signaling predicted poor response to sorafenib therapy in human HCC, and sorafenib resistance of p-Mapk14-expressing HCC cells could be reverted by silencing Mapk14. Our results suggest that a combination of sorafenib and Mapk14 blockade is a promising approach to overcoming therapy resistance of human HCC. PMID:25216638

  17. Hypoxia inducible factor pathway inhibitors as anticancer therapeutics

    PubMed Central

    Burroughs, Sarah K; Kaluz, Stefan; Wang, Danzhu; Wang, Ke

    2013-01-01

    Hypoxia is a significant feature of solid tumor cancers. Hypoxia leads to a more malignant phenotype that is resistant to chemotherapy and radiation, is more invasive and has greater metastatic potential. Hypoxia activates the hypoxia inducible factor (HIF) pathway, which mediates the biological effects of hypoxia in tissues. The HIF complex acts as a transcription factor for many genes that increase tumor survival and proliferation. To date, many HIF pathway inhibitors indirectly affect HIF but there have been no clinically approved direct HIF inhibitors. This can be attributed to the complexity of the HIF pathway, as well as to the challenges of inhibiting protein–protein interactions. PMID:23573973

  18. The Successful Complete Remission Induction by Sorafenib Monotherapy in a FLT3-D835Y-Positive Patient with Refractory Acute Monocytic Leukemia.

    PubMed

    Yue, Yanhua; Jin, Song; Xu, Ting; Zhou, Jin; Ma, Liang; Shen, Hongjie; Wu, Depei; Chen, Suning; Miao, Miao

    2016-06-01

    Sorafenib has been shown to be active in AML patients with FLT3-ITD. However, the effect of sorafenib in AML patients with FLT-TKD has never been well determined. Moreover, acquisition of secondary FLT3 TKD mutations, mainly at D835 (D835F/H/V/Y), are recognized as the major mechanisms of resistance of AML patients with FLT3-ITD to sorafenib. It has been reported that sorafenib induced death of cells that expressed the FLT3-ITD or FLT3-D835G but not cells that expressed the FLT3-D835Y point mutant or wild-type FLT3 in vitro. Here, we report the successful complete remission induction by sorafenib monotherapy in a FLT3-D835Y-positive patient with refractory AML-M5 followed by allogeneic stem cell transplantation. PMID:27408351

  19. Effects of Antitumor Drug Sorafenib on Chick Embryo Development.

    PubMed

    Cheng, Yi-Sen; Wang, Xiao-Yu; Wang, Guang; Li, Yan; Chen, Yue-Lei; Chuai, Man-Li; Lee, Kenneth Ka Ho; Ding, Xiao-Yan; Yang, Xue-Song

    2015-07-01

    Sorafenib has been used as an oral anti-cancer drug because of its ability to inhibit tumor growth. However, the pharmacological effect of sorafenib is still the lack of in vivo experimental evidence. Tumor and embryonic cells share some similar features, so we investigated the effects of sorafenib on the development of gastrulating chick embryos. We found that sorafenib exposure was markedly attributed to the number of embryonic cell in proliferation and apoptosis. We also detected sorafenib significantly interfered with epithelial-mesenchymal transition (EMT). Furthermore, sorafenib treatment impaired the production and migration of neural crest cells. PMID:25810088

  20. Sarcopenia Predicts Early Dose-Limiting Toxicities and Pharmacokinetics of Sorafenib in Patients with Hepatocellular Carcinoma

    PubMed Central

    Mir, Olivier; Coriat, Romain; Blanchet, Benoit; Durand, Jean-Philippe; Boudou-Rouquette, Pascaline; Michels, Judith; Ropert, Stanislas; Vidal, Michel; Pol, Stanislas; Chaussade, Stanislas; Goldwasser, François

    2012-01-01

    Background Sorafenib induces frequent dose limiting toxicities (DLT) in patients with advanced hepatocellular carcinoma (HCC). Sarcopenia has been associated with poor performance status and shortened survival in cancer patients. Patients and Methods The characteristics of Child Pugh A cirrhotic patients with HCC receiving sorafenib in our institution were retrospectively analyzed. Sorafenib plasma concentrations were determined at each visit. Toxicities were recorded during the first month of treatment, and sarcopenia was determined from baseline CT-scans. Results Forty patients (30 males) were included. Eleven (27.5%) were sarcopenic. Eighteen patients (45%) experienced a DLT during the first month of treatment. Sarcopenic patients experienced significantly more DLTs than non-sarcopenic patients did (82% versus 31%, p = 0.005). Grade 3 diarrhea was significantly more frequent in sarcopenic patients than in non-sarcopenic patients (45.5% versus 6.9%, p = 0.01), but not grade 3 hand foot syndrome reaction (9% versus 17.2%, p = 1). On day 28, median sorafenib AUC (n = 17) was significantly higher in sarcopenic patients (102.4 mg/l.h versus 53.7 mg/l.h, p = 0.013). Conclusions Among cirrhotic Child Pugh A patients with advanced HCC, sarcopenia predicts sorafenib exposure and the occurrence of DLT within the first month of treatment. PMID:22666367

  1. Indole-3- carbinol enhances sorafenib cytotoxicity in hepatocellular carcinoma cells: A mechanistic study

    PubMed Central

    Abdelmageed, Mai M.; El-Naga, Reem N.; El-Demerdash, Ebtehal; Elmazar, Mohamed M.

    2016-01-01

    Sorafenib is the only chemotherapeutic agent currently approved for unresectable hepatocellular carcinoma (HCC). However, poor response rates have been widely reported. Indole-3-carbinol (I3C) is a potential chemopreventive phytochemical. The present study aimed to explore the potential chemomodulatory effects of I3C on sorafenib in HCC cells as well as the possible underlying mechanisms. I3C exhibited a greater cytotoxicity in HepG2 cells compared to Huh-7 cells (p < 0.0001). Moreover, the co-treatment of HepG2 cells with I3C and sorafenib was more effective (p = 0.002). Accordingly, subsequent mechanistic studies were carried on HepG2 cells. The results show that the ability of I3C to enhance sorafenib cytotoxicity in HCC cells could be partially attributed to increasing the apoptotic activity and decreasing the angiogenic potentials. The combination had a negative effect on epithelial-mesenchymal transition (EMT). Increased NOX-1 expression was also observed which may indicate the involvement of NOX-1 in I3C chemomodulatory effects. Additionally, the combination induced cell cycle arrest at the G0/G1 phase. In conclusion, these findings provide evidence that I3C enhances sorafenib anti-cancer activity in HCC cells. PMID:27612096

  2. Mechanisms underlying skin disorders induced by EGFR inhibitors

    PubMed Central

    Holcmann, Martin; Sibilia, Maria

    2015-01-01

    The epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase that is frequently mutated or overexpressed in a large number of tumors such as carcinomas or glioblastoma. Inhibitors of EGFR activation have been successfully established for the therapy of some cancers and are more and more frequently being used as first or later line therapies. Although the side effects induced by inhibitors of EGFR are less severe than those observed with classic cytotoxic chemotherapy and can usually be handled by out-patient care, they may still be a cause for dose reduction or discontinuation of treatment that can reduce the effectiveness of antitumor therapy. The mechanisms underlying these cutaneous side effects are only partly understood. Important questions, such as the reasons for the correlation between the intensity of the side effects and the efficiency of treatment with EGFR inhibitors, remain to be answered. Optimized adjuvant strategies to accompany anti-EGFR therapy need to be found for optimal therapeutic application and improved quality of life of patients. Here, we summarize current literature on the molecular and cellular mechanisms underlying the cutaneous side effects induced by EGFR inhibitors and provide evidence that keratinocytes are probably the optimal targets for adjuvant therapy aimed at alleviating skin toxicities. PMID:27308503

  3. Protection from noise-induced hearing loss with Src inhibitors.

    PubMed

    Bielefeld, Eric C

    2015-06-01

    Noise-induced hearing loss is a major cause of acquired hearing loss around the world and pharmacological approaches to protecting the ear from noise are under investigation. Noise results in a combination of mechanical and metabolic damage pathways in the cochlea. The Src family of protein tyrosine kinases could be active in both pathways and Src inhibitors have successfully prevented noise-induced cochlear damage and hearing loss in animal models. The long-term goal is to optimize delivery methods into the cochlea to reduce invasiveness and limit side-effects before human clinical testing can be considered. At their current early stage of research investigation, Src inhibitors represent an exciting class of compounds for inclusion in a multifaceted pharmacological approach to protecting the ear from noise. PMID:25637168

  4. Early onset of hypertension and serum electrolyte changes as potential predictive factors of activity in advanced HCC patients treated with sorafenib: results from a retrospective analysis of the HCC-AVR group

    PubMed Central

    Gardini, Andrea Casadei; Scarpi, Emanuela; Marisi, Giorgia; Foschi, Francesco Giuseppe; Donati, Gabriele; Giampalma, Emanuela; Faloppi, Luca; Scartozzi, Mario; Silvestris, Nicola; Bisulli, Marcello; Corbelli, Jody; Gardini, Andrea; Barba, Giuliano La; Veneroni, Luigi; Tamberi, Stefano; Cascinu, Stefano; Frassineti, Giovanni Luca

    2016-01-01

    Hypertension (HTN) is frequently associated with the use of angiogenesis inhibitors targeting the vascular endothelial growth factor pathway and appears to be a generalized effect of this class of agent. We investigated the phenomenon in 61 patients with advanced hepatocellular carcinoma (HCC) receiving sorafenib. Blood pressure and plasma electrolytes were measured on days 1 and 15 of the treatment. Patients with sorafenib-induced HTN had a better outcome than those without HTN (disease control rate: 63.4% vs. 17.2% (p=0.001); progression-free survival 6.0 months (95% CI 3.2-10.1) vs. 2.5 months (95% CI 1.9-2.6) (p<0.001) and overall survival 14.6 months (95% CI9.7-19.0) vs. 3.9 months (95% CI 3.1-8.7) (p=0.003). Sodium levels were generally higher on day 15 than at baseline (+2.38, p<0.0001) in the group of responders (+4.95, p <0.0001) compared to patients who progressed (PD) (+0.28, p=0.607). In contrast, potassium was lower on day 14 (−0.30, p=0.0008) in the responder group (−0.58, p=0.003) than in those with progressive disease (−0.06, p=0.500). The early onset of hypertension is associated with improved clinical outcome in HCC patients treated with sorafenib. Our data are suggestive of an activation of the renin-angiotensin system in patients with advanced disease who developed HTN during sorafenib treatment. PMID:26893366

  5. Early onset of hypertension and serum electrolyte changes as potential predictive factors of activity in advanced HCC patients treated with sorafenib: results from a retrospective analysis of the HCC-AVR group.

    PubMed

    Casadei Gardini, Andrea; Scarpi, Emanuela; Marisi, Giorgia; Foschi, Francesco Giuseppe; Donati, Gabriele; Giampalma, Emanuela; Faloppi, Luca; Scartozzi, Mario; Silvestris, Nicola; Bisulli, Marcello; Corbelli, Jody; Gardini, Andrea; La Barba, Giuliano; Veneroni, Luigi; Tamberi, Stefano; Cascinu, Stefano; Frassineti, Giovanni Luca

    2016-03-22

    Hypertension (HTN) is frequently associated with the use of angiogenesis inhibitors targeting the vascular endothelial growth factor pathway and appears to be a generalized effect of this class of agent. We investigated the phenomenon in 61 patients with advanced hepatocellular carcinoma (HCC) receiving sorafenib. Blood pressure and plasma electrolytes were measured on days 1 and 15 of the treatment. Patients with sorafenib-induced HTN had a better outcome than those without HTN (disease control rate: 63.4% vs. 17.2% (p=0.001); progression-free survival 6.0 months (95% CI 3.2-10.1) vs. 2.5 months (95% CI 1.9-2.6) (p<0.001) and overall survival 14.6 months (95% CI9.7-19.0) vs. 3.9 months (95% CI 3.1-8.7) (p=0.003). Sodium levels were generally higher on day 15 than at baseline (+2.38, p<0.0001) in the group of responders (+4.95, p <0.0001) compared to patients who progressed (PD) (+0.28, p=0.607). In contrast, potassium was lower on day 14 (-0.30, p=0.0008) in the responder group (-0.58, p=0.003) than in those with progressive disease (-0.06, p=0.500). The early onset of hypertension is associated with improved clinical outcome in HCC patients treated with sorafenib. Our data are suggestive of an activation of the renin-angiotensin system in patients with advanced disease who developed HTN during sorafenib treatment. PMID:26893366

  6. Sorafenib in radioactive iodine-refractory well-differentiated metastatic thyroid cancer

    PubMed Central

    McFarland, Daniel C; Misiukiewicz, Krzysztof J

    2014-01-01

    Recent Phase III data presented at the American Society of Clinical Oncology (ASCO) 2013 annual conference by Brose et al led to the US Food and Drug Administration (FDA) approval of sorafenib for the treatment of well-differentiated radioactive iodine-resistant metastatic thyroid cancer. This is the second drug in 40 years to be FDA approved for this indication. Recent reviews and a meta-analysis reveal a modest ability to induce a partial remission but substantial ability to halt disease progression. Given the significant activating mutations present in thyroid cancer, many of which are inhibited by sorafenib, the next logical approach may be to combine targeted rational therapies if permitted by collective toxicity profiles. This systematic review aims to summarize the recent Phase II/III data leading to the FDA approval of sorafenib for radioactive iodine therapy differentiated thyroid cancer and highlights recent novel combination therapy trials. PMID:25053887

  7. Improving Oral Bioavailability of Sorafenib by Optimizing the "Spring" and "Parachute" Based on Molecular Interaction Mechanisms.

    PubMed

    Liu, Chengyu; Chen, Zhen; Chen, Yuejie; Lu, Jia; Li, Yuan; Wang, Shujing; Wu, Guoliang; Qian, Feng

    2016-02-01

    Sorafenib is a clinically important oral tyrosine kinase inhibitor for the treatment of various cancers. However, the oral bioavailability of sorafenib tablet (Nexavar) is merely 38-49% relative to the oral solution, due to the low aqueous solubility of sorafenib and its relatively high daily dose. It is desirable to improve the oral bioavailability of sorafenib to expand the therapeutic window, reduce the drug resistance, and enhance patient compliance. In this study, we observed that the solubility of sorafenib could be increased ∼50-fold in the coexistence of poly(vinylpyrrolidone-vinyl acetate) (PVP-VA) and sodium lauryl sulfate (SLS), due to the formation of PVP-VA/SLS complexes at a lower critical aggregation concentration. The enhanced solubility provided a faster initial sorafenib dissolution rate, analogous to a forceful "spring" to release drug into solution, from tablets containing both PVP-VA and SLS. However, SLS appears to impair the ability of PVP-VA to act as an efficient "parachute" to keep the drug in solution and maintain drug supersaturation. Using 2D (1)H NMR, (13)C NMR, and FT-IR analysis, we concluded that the solubility enhancement and supersaturation of sorafenib were achieved by PVP-VA/SLS complexes and PVP-VA/sorafenib interaction, respectively, both through molecular interactions hinged on the PVP-VA VA groups. Therefore, a balance between "spring" and "parachute" must be carefully considered in formulation design. To confirm the in vivo relevance of these molecular interaction mechanisms, we prepared three tablet formulations containing PVP-VA alone, SLS alone, and PVP-VA/SLS in combination. The USP II in vitro dissolution and dog pharmacokinetic in vivo evaluation showed clear differentiation between these three formulations, and also good in vitro-in vivo correlation. The formulation containing PVP-VA alone demonstrated the best bioavailability with 1.85-fold and 1.79-fold increases in Cmax and AUC, respectively, compared with the

  8. Prostaglandin synthesis inhibitors block alcohol-induced fetal hypoplasia.

    PubMed

    Pennington, S; Allen, Z; Runion, J; Farmer, P; Rowland, L; Kalmus, G

    1985-01-01

    Alcohol-induced growth retardation is a fetal effect consistently associated with maternal ethanol consumption. In humans, those infants whose mothers consume even a limited amount of ethanol during pregnancy have a significant incidence of growth inhibition. The molecular mechanism responsible for this growth deficiency is unknown, and prevention depends on maternal abstinence during pregnancy. The data reported here suggest that ethanol-mediated increases in tissue prostaglandin (PG) E levels (PGE1 plus PGE2) are correlated with the growth retardation. Further, simultaneous administration of PG synthesis inhibitors with the alcohol blocks the rise in tissue PG levels and protects against the alcohol-induced hypoplasia. PMID:3904508

  9. Synergistic effect of sorafenib and cGvHD in patients with high-risk FLT3-ITD+AML allows long-term disease control after allogeneic transplantation.

    PubMed

    Tschan-Plessl, A; Halter, J P; Heim, D; Medinger, M; Passweg, J R; Gerull, S

    2015-11-01

    The multikinase inhibitor sorafenib has shown a strong anti-leukemic effect in FMS-like tyrosine kinase 3 (FLT3)-mutated acute myeloid leukemia (AML); however, remission is often transient. To better understand the role of sorafenib, we performed a retrospective analysis of all patients who received sorafenib in combination with allogeneic hematopoietic stem cell transplantation (HSCT) at our center. Seventeen patients with FLT3-ITD positive AML were treated with sorafenib in combination with allogeneic HSCT. Seven patients received sorafenib therapy pre- and posttransplant, and 10 patients were given sorafenib only posttransplant. Median duration of sorafenib treatment was 13 months (range 1-42); median dose was 600 mg (range 100-1200). Fourteen patients (82 %) achieved a complete remission (CR), while 5 patients (29 %) eventually developed progressive disease. Developing chronic graft-versus-host disease (GvHD) had a strong protective influence on the risk of sorafenib resistance (p = 0.028, HR 0.08, 95 % CI 0.01-0.76). In a total of 8 patients, sorafenib had to be stopped, paused or dose-reduced due to toxicity. In 5 patients with pronounced toxicity, we switched to an alternating dosing schedule with 1 month on/1 month off sorafenib. These patients subsequently remained in sustained complete molecular remission, with a median follow-up of 20 months. Our data indicate that sorafenib can achieve high rates of sustained remission in high-risk patients treated in combination with HSCT. PMID:26233683

  10. Quantitative proteomics and phosphoproteomics on serial tumor biopsies from a sorafenib-treated HCC patient.

    PubMed

    Dazert, Eva; Colombi, Marco; Boldanova, Tujana; Moes, Suzette; Adametz, David; Quagliata, Luca; Roth, Volker; Terracciano, Luigi; Heim, Markus H; Jenoe, Paul; Hall, Michael N

    2016-02-01

    Compensatory signaling pathways in tumors confer resistance to targeted therapy, but the pathways and their mechanisms of activation remain largely unknown. We describe a procedure for quantitative proteomics and phosphoproteomics on snap-frozen biopsies of hepatocellular carcinoma (HCC) and matched nontumor liver tissue. We applied this procedure to monitor signaling pathways in serial biopsies taken from an HCC patient before and during treatment with the multikinase inhibitor sorafenib. At diagnosis, the patient had an advanced HCC. At the time of the second biopsy, abdominal imaging revealed progressive disease despite sorafenib treatment. Sorafenib was confirmed to inhibit MAPK signaling in the tumor, as measured by reduced ribosomal protein S6 kinase phosphorylation. Hierarchical clustering and enrichment analysis revealed pathways broadly implicated in tumor progression and resistance, such as epithelial-to-mesenchymal transition and cell adhesion pathways. Thus, we describe a protocol for quantitative analysis of oncogenic pathways in HCC biopsies and obtained first insights into the effect of sorafenib in vivo. This protocol will allow elucidation of mechanisms of resistance and enable precision medicine. PMID:26787912

  11. Quantitative proteomics and phosphoproteomics on serial tumor biopsies from a sorafenib-treated HCC patient

    PubMed Central

    Dazert, Eva; Colombi, Marco; Boldanova, Tujana; Moes, Suzette; Adametz, David; Quagliata, Luca; Roth, Volker; Terracciano, Luigi; Heim, Markus H.; Jenoe, Paul; Hall, Michael N.

    2016-01-01

    Compensatory signaling pathways in tumors confer resistance to targeted therapy, but the pathways and their mechanisms of activation remain largely unknown. We describe a procedure for quantitative proteomics and phosphoproteomics on snap-frozen biopsies of hepatocellular carcinoma (HCC) and matched nontumor liver tissue. We applied this procedure to monitor signaling pathways in serial biopsies taken from an HCC patient before and during treatment with the multikinase inhibitor sorafenib. At diagnosis, the patient had an advanced HCC. At the time of the second biopsy, abdominal imaging revealed progressive disease despite sorafenib treatment. Sorafenib was confirmed to inhibit MAPK signaling in the tumor, as measured by reduced ribosomal protein S6 kinase phosphorylation. Hierarchical clustering and enrichment analysis revealed pathways broadly implicated in tumor progression and resistance, such as epithelial-to-mesenchymal transition and cell adhesion pathways. Thus, we describe a protocol for quantitative analysis of oncogenic pathways in HCC biopsies and obtained first insights into the effect of sorafenib in vivo. This protocol will allow elucidation of mechanisms of resistance and enable precision medicine. PMID:26787912

  12. Sorafenib

    MedlinePlus

    ... Tegretol), dexamethasone, dofetilide (Tikosyn), dronedarone (Multaq), ibutilide (Corvert), irinotecan (Camptosar), neomycin, phenobarbital, phenytoin (Dilantin, Phenytek), procainamide (Procanbid, ...

  13. Phase I Trial of Maintenance Sorafenib after Allogeneic Hematopoietic Stem Cell Transplantation for FLT3-ITD AML

    PubMed Central

    Chen, Yi-Bin; Li, Shuli; Lane, Andrew A.; Connolly, Christine; Del Rio, Candice; Valles, Betsy; Curtis, Morgan; Ballen, Karen; Cutler, Corey; Dey, Bimalangshu R.; El-Jawahri, Areej; Fathi, Amir T.; Ho, Vincent T.; Joyce, Amy; McAfee, Steven; Rudek, Michelle; Rajkhowa, Trivikram; Verselis, Sigitas; Antin, Joseph H.; Spitzer, Thomas R.; Levis, Mark; Soiffer, Robert

    2014-01-01

    The FLT3-ITD mutation is associated with a high relapse rate for patients with AML even after allogeneic hematopoietic stem cell transplantation (HSCT). Sorafenib is a tyrosine kinase inhibitor which inhibits the FLT3 tyrosine kinase and has shown encouraging activity in FLT3-ITD AML. We conducted a phase I trial of maintenance sorafenib after HSCT in patients with FLT3-ITD AML (ClinicalTrials.gov NCT01398501). Patients received a variety of conditioning regimens and graft sources. A dose escalation 3+3 cohort design was used to define the maximum tolerated dose (MTD) with an additional 10 patients treated at the MTD. Sorafenib was initiated between days 45 and 120 after HSCT continued for twelve 28-day cycles. Twenty-two patients were enrolled (status at HSCT: CR1=16, CR2=3, refractory=3). The MTD was established at 400 mg BID with one DLT observed (pericardial effusion). Two patients died of transplant-related causes, both unrelated to sorafenib. Two patients stopped sorafenib after relapse and 5 stopped due to attributable toxicities after the DLT period. Median follow-up for surviving patients is 16.7 months after HSCT (range, 8.1–35.0). There was one case of grade II acute GVHD after starting sorafenib and the 12-month cumulative incidence of chronic GVHD was 38% (90% CI, 21%–56%). For all patients, one-year progression-free survival (PFS) is 85% (90% CI, 66%–94%) and one-year overall survival (OS) is 95% (90% CI, 79%–99%) after HSCT. For patients in CR1 / CR2 prior to HSCT (n=19), one-year PFS is 95% (90% CI, 76%–99%) and one-year OS is 100% with only one patient who has relapsed. Sorafenib is safe after HSCT for FLT3-ITD AML and merits further investigation for the prevention of relapse. PMID:25239228

  14. Sorafenib treatment of radioiodine-refractory advanced thyroid cancer in daily clinical practice: a cohort study from a single center.

    PubMed

    Gallo, Marco; Michelon, Federica; Castiglione, Anna; Felicetti, Francesco; Viansone, Alessandro Adriano; Nervo, Alice; Zichi, Clizia; Ciccone, Giovannino; Piovesan, Alessandro; Arvat, Emanuela

    2015-08-01

    Treatment options for recurrent or metastatic differentiated thyroid cancer (DTC) refractory to radioactive iodine (RAI) are inadequate. Multitargeted kinase inhibitors have recently shown promising results in phase 2-3 studies. This retrospective study aimed to document our clinical experience on the effects of sorafenib in the setting of daily clinical practice. Retrospective study evaluating the efficacy and safety of sorafenib in a cohort of patients consecutively treated with sorafenib at a single center. Twenty patients with advanced RAI-refractory thyroid carcinoma were enrolled (March 2011-March 2014). Patients generally started with 400 mg of sorafenib twice daily, tapering the dose in case of side effects. Radiological response and toxicity were measured during follow-up, together with safety parameters. CT scans were performed by a single experienced radiologist every 3-4 months. Five patients stopped sorafenib within 90 days due to severe toxicities. Median progression-free survival was 248 days. Five patients had a partial response (PR), achieved in all cases within 3 months, whereas 5 had stable disease (SD) at 12 months. Durable response rate (PR plus SD) for at least 6 months was 50 %, among those who received sorafenib for at least 3 months. Commonest adverse events included skin toxicity, gastrointestinal and constitutional symptoms. In our cohort of patients with advanced RAI-refractory thyroid carcinoma, sorafenib confirmed antitumor activity leading to SD or PR in the majority of cases, at the expense of clinically relevant side effects. More effective and tolerable agents are still needed in the treatment of RAI-refractory DTC. PMID:25414068

  15. ACE inhibitor potentiation of bradykinin-induced venoconstriction

    PubMed Central

    Hecker, Markus; Blaukat, Andree; Bara, Agnieszka T; Müller-Esterl, Werner; Busse, Rudi

    1997-01-01

    Angiotensin-converting enzyme (ACE) inhibitors exert their cardiovascular effects not only by preventing the formation of angiotensin II (AII), but also by promoting the accumulation of bradykinin in or at the vessel wall. In addition, certain ACE inhibitors have been shown to augment the vasodilator response to bradykinin, presumably by an interaction at the level of the B2 receptor. We have investigated whether this is a specific effect of the ACE inhibitor class of compounds in isolated endothelium-denuded segments of the rabbit jugular vein where bradykinin elicits a constrictor response which is exclusively mediated by activation of the B2 receptor. Moexiprilat and ramiprilat (⩽ 3 nM) enhanced the constrictor response to bradykinin three to four fold. Captopril and enalaprilat were less active by approximately one and quinaprilat by two orders of magnitude. Moexiprilat and ramiprilat, on the other hand, had no effect on the constrictor response to AII or the dilator response to acetylcholine. The bradykinin-potentiating effect of the ACE inhibitors was not mimicked by inhibitors of amino-, carboxy-, metallo- or serine peptidases or the synthetic ACE substrate, hippuryl-L-histidyl-L-leucine, at a concentration which almost abolished the residual ACE activity in the vessel wall. In contrast, angiotensin-(1–7) (10 μM), an angiotensin I metabolite, significantly enhanced the constrictor response to bradykinin. Ramiprilat did not alter the binding of [3H]-bradykinin to a membrane fraction prepared from endothelium-denuded rabbit jugular veins or to cultured fibroblasts, and there was no ACE inhibitor-sensitive, bradykinin-induced cleavage of the B2 receptor in cultured endothelial cells. These findings demonstrate that ACE inhibitors selectively potentiate the B2 receptor-mediated vascular effects of bradykinin. Their relative efficacy appears to be independent of their ACE-inhibiting properties and might be related to differences in molecule structure

  16. Meloxicam combined with sorafenib synergistically inhibits tumor growth of human hepatocellular carcinoma cells via ER stress-related apoptosis.

    PubMed

    Zhong, Jingtao; Xiu, Peng; Dong, Xiaofeng; Wang, Fuhai; Wei, Honglong; Wang, Xin; Xu, Zongzhen; Liu, Feng; Li, Tao; Wang, Yong; Li, Jie

    2015-10-01

    Sorafenib (SOR) is a promising treatment for advanced hepatocellular carcinoma (HCC). However, the precise mechanisms of toxicity and drug resistance have not been fully explored and new strategies are urgently needed for HCC therapy. Meloxicam (MEL) is a selective cyclooxygenase-2 (COX-2) inhibitor which elicits antitumor effects in human HCC cells. In the present study, we investigated the interaction between MEL and SOR in human SMMC‑7721 cells and the role endoplasmic reticulum (ER) stress exerts in the combination of SOR with MEL treatment-induced cytotoxicity. Our results revealed that the combination treatment synergistically inhibited cell proliferation and enhanced apoptosis. Furthermore, the combination treatment enhanced ER stress-related molecules which involved in SMMC-7721 cell apoptosis. GRP78 knockdown by siRNA or co-treatment with MG132 significantly increased this combination treatment-induced apoptosis. In addition, we found that the combination treatment suppressed tumor growth by way of activation of ER stress in in vivo models. We concluded that the combination of SOR with MEL treatment-induced ER stress, and eventually apoptosis in human SMMC-7721 cells. Knockdown of GRP78 using siRNA or proteosome inhibitor enhanced the cytotoxicity of the combination of SOR with MEL-treatment in SMMC-7721 cells. These findings provided a new potential treatment strategy against HCC. PMID:26252057

  17. Phase I Study of Lenalidomide and Sorafenib in Patients With Advanced Hepatocellular Carcinoma

    PubMed Central

    Loehrer, Patrick J.; Clark, Romnee S.; Spittler, A. John; Althouse, Sandra K.; Chiorean, E. Gabriella

    2016-01-01

    Lessons Learned Combination therapies in patients with hepatocellular carcinoma can be associated with overlapping toxicity and are therefore poorly tolerated. Using sorafenib at the maximum tolerated dose can lead to a higher incidence of toxicities. Consequently, combination studies might evaluate sorafenib at alternative schedules or doses to improve tolerance, recognizing this could affect sorafenib efficacy. Although this combination was poorly tolerated, it does not exclude further evaluation of new-generation immunomodulator drugs or immune checkpoint inhibitors in the hope of optimizing tolerance and safety. Background. Sorafenib is the standard treatment for advanced hepatocellular carcinoma (HCC), and to date, no combination therapy has demonstrated superior survival compared with sorafenib alone. The immunosuppressive microenvironment in HCC is a negative predictor for survival. Lenalidomide is an immunomodulator and antiangiogenic agent, with limited single-agent efficacy in HCC. Based on these data, we designed a phase I study of sorafenib plus lenalidomide to determine the safety and preliminary antitumor activity of this combination. Methods. This was an open-label, phase I study with a 3+3 dose escalation/de-escalation design. The starting dose of sorafenib was 400 mg p.o. b.i.d. and of lenalidomide was 15 mg p.o. daily with a planned dose escalation by 5 mg per cohort up to 25 mg daily. Dose de-escalation was planned to a sorafenib dose of 400 mg p.o. daily combined with two doses of lenalidomide: 10 mg p.o. daily for a 28-day cycle (cohort 1) and 10 mg p.o. daily for a 21- or 28-day cycle (cohort 2). Patients with cirrhosis, a Child-Pugh score of A-B7, and no previous systemic therapy were eligible. Results. Five patients were enrolled. Their median age was 56 years (range 39–61), and the ECOG status was 0–2. Four patients were treated at dose level (DL) 1. Because of the poor tolerance to the combination associated with grade 2 toxicities

  18. A significant response to sorafenib in a woman with advanced lung adenocarcinoma and a BRAF non-V600 mutation.

    PubMed

    Sereno, María; Moreno, Victor; Moreno Rubio, Juan; Gómez-Raposo, César; García Sánchez, Sagrario; Hernández Jusdado, Rebeca; Falagan, Sandra; Zambrana Tébar, Francisco; Casado Sáenz, Enrique

    2015-10-01

    Lung adenocarcinoma includes recurrent activating oncogenic mutations (EGFR, EML4-ALK, ROS1) that have been associated with response to EGFR and ALK inhibitors. Platinum-based chemotherapy is the standard therapy for non-oncodrivers population. Sorafenib is a small molecule that blocks the activation of C-RAF, B-RAF, c-KIT, FLT-3, RET, VEGFR-2, VEGFR-3 and PDGFR approved for advanced renal cell and hepatocellular carcinoma (b, c). Many studies have evaluated sorafenib in advanced non-small-cell lung cancer (NSCLC), with different results. We present a case report of a patient with NSCLC and the BRAF G469R mutation who showed a dramatic response to sorafenib. PMID:26237499

  19. Temsirolimus combined with sorafenib in hepatocellular carcinoma: a phase I dose-finding trial with pharmacokinetic and biomarker correlates

    PubMed Central

    Kelley, R. K.; Nimeiri, H. S.; Munster, P. N.; Vergo, M. T.; Huang, Y.; Li, C.-M.; Hwang, J.; Mulcahy, M. F.; Yeh, B. M.; Kuhn, P.; Luttgen, M. S.; Grabowsky, J. A.; Stucky-Marshall, L.; Korn, W. M.; Ko, A. H.; Bergsland, E. K.; Benson, A. B.; Venook, A. P.

    2013-01-01

    Background Based upon preclinical evidence for improved antitumor activity in combination, this phase I study investigated the maximum-tolerated dose (MTD), safety, activity, pharmacokinetics (PK), and biomarkers of the mammalian target of rapamycin inhibitor, temsirolimus, combined with sorafenib in hepatocellular carcinoma (HCC). Patients and methods Patients with incurable HCC and Child Pugh score ≤B7 were treated with sorafenib plus temsirolimus by 3 + 3 design. The dose-limiting toxicity (DLT) interval was 28 days. The response was assessed every two cycles. PK of temsirolimus was measured in a cohort at MTD. Results Twenty-five patients were enrolled. The MTD was temsirolimus 10 mg weekly plus sorafenib 200 mg twice daily. Among 18 patients at MTD, DLT included grade 3 hand–foot skin reaction (HFSR) and grade 3 thrombocytopenia. Grade 3 or 4 related adverse events at MTD included hypophosphatemia (33%), infection (22%), thrombocytopenia (17%), HFSR (11%), and fatigue (11%). With sorafenib, temsirolimus clearance was more rapid (P < 0.05). Two patients (8%) had a confirmed partial response (PR); 15 (60%) had stable disease (SD). Alpha-fetoprotein (AFP) declined ≥50% in 60% assessable patients. Conclusion The MTD of sorafenib plus temsirolimus in HCC was lower than in other tumor types. HCC-specific phase I studies are necessary. The observed efficacy warrants further study. PMID:23519998

  20. The value of lactate dehydrogenase serum levels as a prognostic and predictive factor for advanced pancreatic cancer patients receiving sorafenib

    PubMed Central

    Faloppi, Luca; Bianconi, Maristella; Giampieri, Riccardo; Sobrero, Alberto; Labianca, Roberto; Ferrari, Daris; Barni, Sandro; Aitini, Enrico; Zaniboni, Alberto; Boni, Corrado; Caprioni, Francesco; Mosconi, Stefania; Fanello, Silvia; Berardi, Rossana; Bittoni, Alessandro; Andrikou, Kalliopi; Cinquini, Michela; Torri, Valter; Scartozzi, Mario; Cascinu, Stefano

    2015-01-01

    Although lactate dehydrogenase (LDH) serum levels, indirect markers of angiogenesis, are associated with a worse outcome in several tumours, their prognostic value is not defined in pancreatic cancer. Moreover, high levels are associated even with a lack of efficacy of tyrosine kinase inhibitors, contributing to explain negative results in clinical trials. We assessed the role of LDH in advanced pancreatic cancer receiving sorafenib. Seventy-one of 114 patients included in the randomised phase II trial MAPS (chemotherapy plus or not sorafenib) and with available serum LDH levels, were included in this analysis. Patients were categorized according to serum LDH levels (LDH ≤vs.> upper normal rate). A significant difference was found in progression free survival (PFS) and in overall survival (OS) between patients with LDH values under or above the cut-off (PFS: 5.2 vs. 2.7 months, p = 0.0287; OS: 10.7 vs. 5.9 months, p = 0.0021). After stratification according to LDH serum levels and sorafenib treatment, patients with low LDH serum levels treated with sorafenib showed an advantage in PFS (p = 0.05) and OS (p = 0.0012). LDH appears to be a reliable parameter to assess the prognosis of advanced pancreatic cancer patients, and it may be a predictive parameter to select patients candidate to receive sorafenib. PMID:26397228

  1. The value of lactate dehydrogenase serum levels as a prognostic and predictive factor for advanced pancreatic cancer patients receiving sorafenib.

    PubMed

    Faloppi, Luca; Bianconi, Maristella; Giampieri, Riccardo; Sobrero, Alberto; Labianca, Roberto; Ferrari, Daris; Barni, Sandro; Aitini, Enrico; Zaniboni, Alberto; Boni, Corrado; Caprioni, Francesco; Mosconi, Stefania; Fanello, Silvia; Berardi, Rossana; Bittoni, Alessandro; Andrikou, Kalliopi; Cinquini, Michela; Torri, Valter; Scartozzi, Mario; Cascinu, Stefano

    2015-10-27

    Although lactate dehydrogenase (LDH) serum levels, indirect markers of angiogenesis, are associated with a worse outcome in several tumours, their prognostic value is not defined in pancreatic cancer. Moreover, high levels are associated even with a lack of efficacy of tyrosine kinase inhibitors, contributing to explain negative results in clinical trials. We assessed the role of LDH in advanced pancreatic cancer receiving sorafenib. Seventy-one of 114 patients included in the randomised phase II trial MAPS (chemotherapy plus or not sorafenib) and with available serum LDH levels, were included in this analysis. Patients were categorized according to serum LDH levels (LDH ≤ vs.> upper normal rate). A significant difference was found in progression free survival (PFS) and in overall survival (OS) between patients with LDH values under or above the cut-off (PFS: 5.2 vs. 2.7 months, p = 0.0287; OS: 10.7 vs. 5.9 months, p = 0.0021). After stratification according to LDH serum levels and sorafenib treatment, patients with low LDH serum levels treated with sorafenib showed an advantage in PFS (p = 0.05) and OS (p = 0.0012). LDH appears to be a reliable parameter to assess the prognosis of advanced pancreatic cancer patients, and it may be a predictive parameter to select patients candidate to receive sorafenib. PMID:26397228

  2. Distinct antifibrogenic effects of erlotinib, sunitinib and sorafenib on rat pancreatic stellate cells

    PubMed Central

    Elsner, Anne; Lange, Falko; Fitzner, Brit; Heuschkel, Martin; Krause, Bernd Joachim; Jaster, Robert

    2014-01-01

    AIM: To study if three clinically available small molecule kinase inhibitors (SMI), erlotinib, sunitinib and sorafenib, exert antifibrogenic effects on pancreatic stellate cells (PSC) and analyze the basis of their action. METHODS: Cultured rat PSC were exposed to SMI. Cell proliferation and viability were assessed employing 5-bromo-2’-deoxyuridine incorporation assay and flow cytometry, respectively. 2-Deoxy-2-[18F] fluoroglucose (18F-FDG) uptake was measured to study metabolic activity. Exhibition of the myofibroblastic PSC phenotype was monitored by immunofluorescence analysis of α-smooth muscle actin (α-SMA) expression. Levels of mRNA were determined by real-time PCR, while protein expression and phosphorylation were analyzed by immunoblotting. Transforming growth factor-β1 (TGF-β1) levels in culture supernatants were quantified by ELISA. RESULTS: All three SMI inhibited cell proliferation and 18F-FDG uptake in a dose-dependent manner and without significant cytotoxic effects. Furthermore, additive effects of the drugs were observed. Immunoblot analysis showed that sorafenib and sunitib, but not erlotinib, efficiently blocked activation of the AKT pathway, while all three drugs displayed little effect on phosphorylation of ERK1/2. Cells treated with sorafenib or sunitinib expressed less interleukin-6 mRNA as well as less collagen type 1 mRNA and protein. Sorafenib was the only drug that also upregulated the expression of matrix metalloproteinase-2 and reduced the secretion of TGF-β1 protein. All three drugs showed insignificant or discordant effects on the mRNA and protein levels of α-SMA. CONCLUSION: The tested SMI, especially sorafenib, exert inhibitory effects on activated PSC, which should be further evaluated in preclinical studies. PMID:24976727

  3. Formation of Tankyrase Inhibitor-Induced Degradasomes Requires Proteasome Activity

    PubMed Central

    Pedersen, Nina Marie; Thorvaldsen, Tor Espen; Schultz, Sebastian Wolfgang; Wenzel, Eva Maria; Stenmark, Harald

    2016-01-01

    In canonical Wnt signaling, the protein levels of the key signaling mediator β-catenin are under tight regulation by the multimeric destruction complex that mediates proteasomal degradation of β-catenin. In colorectal cancer, destruction complex activity is often compromised due to mutations in the multifunctional scaffolding protein Adenomatous Polyposis Coli (APC), leading to a stabilization of β-catenin. Recently, tankyrase inhibitors (TNKSi), a novel class of small molecule inhibitors, were shown to re-establish a functional destruction complex in APC-mutant cancer cell lines by stabilizing AXIN1/2, whose protein levels are usually kept low via poly(ADP-ribosyl)ation by the tankyrase enzymes (TNKS1/2). Surprisingly, we found that for the formation of the morphological correlates of destruction complexes, called degradasomes, functional proteasomes are required. In addition we found that AXIN2 is strongly upregulated after 6 h of TNKS inhibition. The proteasome inhibitor MG132 counteracted TNKSi-induced degradasome formation and AXIN2 stabilization, and this was accompanied by reduced transcription of AXIN2. Mechanistically we could implicate the transcription factor FoxM1 in this process, which was recently shown to be a transcriptional activator of AXIN2. We observed a substantial reduction in TNKSi-induced stabilization of AXIN2 after siRNA-mediated depletion of FoxM1 and found that proteasome inhibition reduced the active (phosphorylated) fraction of FoxM1. This can explain the decreased protein levels of AXIN2 after MG132 treatment. Our findings have implications for the design of in vitro studies on the destruction complex and for clinical applications of TNKSi. PMID:27482906

  4. Histone deacetylase inhibitors block IFNγ-induced STAT1 phosphorylation.

    PubMed

    Ginter, Torsten; Bier, Carolin; Knauer, Shirley K; Sughra, Kalsoom; Hildebrand, Dagmar; Münz, Tobias; Liebe, Theresa; Heller, Regine; Henke, Andreas; Stauber, Roland H; Reichardt, Werner; Schmid, Johannes A; Kubatzky, Katharina F; Heinzel, Thorsten; Krämer, Oliver H

    2012-07-01

    Signal transducer and activator of transcription 1 (STAT1) is important for innate and adaptive immunity. Histone deacetylase inhibitors (HDACi) antagonize unbalanced immune functions causing chronic inflammation and cancer. Phosphorylation and acetylation regulate STAT1 and different IFNs induce phosphorylated STAT1 homo-/heterodimers, e.g. IFNα activates several STATs whereas IFNγ only induces phosphorylated STAT1 homodimers. In transformed cells HDACi trigger STAT1 acetylation linked to dephosphorylation by the phosphatase TCP45. It is unclear whether acetylation differentially affects STAT1 activated by IFNα or IFNγ, and if cellular responses to both cytokines depend on a phosphatase-dependent inactivation of acetylated STAT1. Here, we report that HDACi counteract IFN-induced phosphorylation of a critical tyrosine residue in the STAT1 C-terminus in primary cells and hematopoietic cells. STAT1 mutants mimicking a functionally inactive DNA binding domain (DBD) reveal that the number of acetylation-mimicking sites in STAT1 determines whether STAT1 is recruited to response elements after stimulation with IFNγ. Furthermore, we show that IFNα-induced STAT1 heterodimers carrying STAT1 molecules mimicking acetylation bind cognate DNA and provide innate anti-viral immunity. IFNγ-induced acetylated STAT1 homodimers are though inactive, suggesting that heterodimerization and complex formation can rescue STAT1 lacking a functional DBD. Apparently, the type of cytokine determines how acetylation affects the nuclear entry and DNA binding of STAT1. Our data contribute to a better understanding of STAT1 regulation by acetylation. PMID:22425562

  5. Comparative Metabolomic Profiling of Hepatocellular Carcinoma Cells Treated with Sorafenib Monotherapy vs. Sorafenib-Everolimus Combination Therapy

    PubMed Central

    Zheng, Jian-feng; Lu, Juan; Wang, Xiao-zhong; Guo, Wu-hua; Zhang, Ji-xiang

    2015-01-01

    Background Sorafenib-everolimus combination therapy may be more effective than sorafenib monotherapy for hepatocellular carcinoma (HCC). To better understand this effect, we comparatively profiled the metabolite composition of HepG2 cells treated with sorafenib, everolimus, and sorafenib-everolimus combination therapy. Material/Methods A 2D HRMAS 1H-NMR metabolomic approach was applied to identify the key differential metabolites in 3 experimental groups: sorafenib (5 μM), everolimus (5 μM), and combination therapy (5 μM sorafenib +5 μM everolimus). MetaboAnalyst 3.0 was used to perform pathway analysis. Results All OPLS-DA models displayed good separation between experimental groups, high-quality goodness of fit (R2), and high-quality goodness of predication (Q2). Sorafenib and everolimus have differential effects with respect to amino acid, methane, pyruvate, pyrimidine, aminoacyl-tRNA biosynthesis, and glycerophospholipid metabolism. The addition of everolimus to sorafenib resulted in differential effects with respect to pyruvate, amino acid, methane, glyoxylate and dicarboxylate, glycolysis or gluconeogenesis, glycerophospholipid, and purine metabolism. Conclusions Sorafenib and everolimus have differential effects on HepG2 cells. Sorafenib preferentially affects glycerophospholipid and purine metabolism, while the addition of everolimus preferentially affects pyruvate, amino acid, and glucose metabolism. This phenomenon may explain (in part) the synergistic effects of sorafenib-everolimus combination therapy observed in vivo. PMID:26092946

  6. Down-regulation of Mcl-1 through GSK-3β activation contributes to arsenic trioxide-induced apoptosis in acute myeloid leukemia cells

    PubMed Central

    Wang, Rui; Xia, Lijuan; Gabrilove, Janice; Waxman, Samuel; Jing, Yongkui

    2012-01-01

    Arsenic trioxide (ATO) induces disease remission in acute promyelocytic leukemia (APL) patients, but not in non-APL acute myeloid leukemia (AML) patients. ATO at therapeutic concentrations (1-2 μM) induce APL NB4, but not non-APL HL-60, cells to undergo apoptosis through the mitochondrial pathway. The role of antiapoptotic protein Mcl-1 in ATO-induced apoptosis was determined. The levels of Mcl-1 were decreased in NB4, but not in HL-60, cells after ATO treatment through proteasomal degradation. Both GSK3β inhibitor SB216763 and siRNA blocked ATO-induced Mcl-1 reduction as well as attenuated ATO-induced apoptosis in NB4 cells. Silencing Mcl-1 sensitized HL-60 cells to ATO-induced apoptosis. Both ERK and AKT inhibitors decreased Mcl-1 levels and enhanced ATO-induced apoptosis in HL-60 cells. Sorafenib, a Raf inhibitor, activated GSK3β by inhibiting its phosphorylation, decreased Mcl-1 levels, and decreased intracellular glutathione levels in HL-60 cells. Sorafenib plus ATO augmented ROS production and apoptosis induction in HL-60 cells and in primary AML cells. These results indicate that ATO induces Mcl-1 degradation through activation of GSK3β in APL cells and provide a rationale for utilizing ATO in combination with sorafenib for the treatment of non-APL AML patients. PMID:22751450

  7. Tyrosine receptor kinase B silencing inhibits anoikis‑resistance and improves anticancer efficiency of sorafenib in human renal cancer cells.

    PubMed

    Zhang, Peng; Xing, Zengshu; Li, Xuechao; Song, Yarong; Zhao, Jun; Xiao, Yajun; Xing, Yifei

    2016-04-01

    Renal cell carcinoma (RCC) is the most common solid neoplasm of adult kidney, and the major treatment for metastatic RCC (mRCC) is molecular targeted therapy. Sorafenib, as a multi-targeted tyrosine kinase inhibitor (TKI), has significantly improved clinical outcomes of mRCC patients. However, complete or long-term remissions are rarely achieved due to intolerance to dose-related adverse effects. It is therefore, necessary to explore novel target molecules for treatment or to enhance the therapeutic efficiency of present TKI for mRCC treatment. Anoikis is a specific type of apoptosis that plays a vital physiological role in regulating tissue homoeostasis. Anoikis-resistance is of critical importance for metastasis of various human cancers including mRCC. However, the precise mechanisms on anoikis-resistance in mRCC are still unclear. Tyrosine receptor kinase B (TrkB) belongs to the Trk family of neurotrophin receptors. Previous investigations have implied that activation or overexpression of TrkB promoted proliferation, survival, angiogenesis, anoikis-resistance and metastasis in human cancers. Yet, the correlation between TrkB and anoikis-resistance in mRCC has rarely been reported. The aim of the present study was to explore the impact of TrkB on anoikis-resistance and targeted therapy in mRCC. Our data revealed that anoikis-resistant ACHN cells presented with tolerance to detachment-induced apoptosis, excessive proliferation and aggressive invasion, accompanied by upregulation of TrkB expression in contrast to parental cells. Furthermore, TrkB silencing caused apoptosis, inhibited proliferation, retarded invasion as well as improved anticancer efficiency of sorafenib in anoikis-resistant ACHN cells through inactivation of PI3K/Akt and MEK/ERK pathways. Our data may offer a novel potential therapeutic strategy for mRCC. PMID:26820170

  8. The NADPH oxidase inhibitor apocynin (acetovanillone) induces oxidative stress

    SciTech Connect

    Riganti, Chiara . E-mail: dario.ghigo@unito.it

    2006-05-01

    Apocynin (acetovanillone) is often used as a specific inhibitor of NADPH oxidase. In N11 glial cells, apocynin induced, in a dose-dependent way, a significant increase of both malonyldialdehyde level (index of lipid peroxidation) and lactate dehydrogenase release (index of a cytotoxic effect). Apocynin evoked also, in a significant way, an increase of H{sub 2}O{sub 2} concentration and a decrease of the intracellular glutathione/glutathione disulfide ratio, accompanied by augmented efflux of glutathione and glutathione disulfide. Apocynin induced the activation of both pentose phosphate pathway and tricarboxylic acid cycle, which was blocked when the cells were incubated with glutathione together with apocynin. The cell incubation with glutathione prevented also the apocynin-induced increase of malonyldialdehyde generation and lactate dehydrogenase leakage. Apocynin exerted an oxidant effect also in a cell-free system: indeed, in aqueous solution, it evoked a faster oxidation of the thiols glutathione and dithiothreitol, and elicited the generation of reactive oxygen species, mainly superoxide anions. Our results suggest that apocynin per se can induce an oxidative stress and exert a cytotoxic effect in N11 cells and other cell types, and that some effects of apocynin in in vitro and in vivo experimental models should be interpreted with caution.

  9. Serial Low Doses of Sorafenib Enhance Therapeutic Efficacy of Adoptive T Cell Therapy in a Murine Model by Improving Tumor Microenvironment

    PubMed Central

    Liu, Ren-Shyan; Hwang, Jeng-Jong

    2014-01-01

    Requirements of large numbers of transferred T cells and various immunosuppressive factors and cells in the tumor microenvironment limit the applications of adoptive T cells therapy (ACT) in clinic. Accumulating evidences show that chemotherapeutic drugs could act as immune supportive instead of immunosuppressive agents when proper dosage is used, and combined with immunotherapy often results in better treatment outcomes than monotherapy. Controversial immunomodulation effects of sorafenib, a multi-kinases inhibitor, at high and low doses have been reported in several types of cancer. However, what is the range of the low-dose sorafenib will influence the host immunity and responses of ACT is still ambiguous. Here we used a well-established E.G7/OT-1 murine model to understand the effects of serial low doses of sorafenib on both tumor microenvironment and transferred CD8+ T cells and the underlying mechanisms. Sorafenib lowered the expressions of immunosuppressive factors, and enhanced functions and migrations of transferred CD8+ T cells through inhibition of STAT3 and other immunosuppressive factors. CD8+ T cells were transduced with granzyme B promoter for driving imaging reporters to visualize the activation and distribution of transferred CD8+ T cells prior to adoptive transfer. Better activations of CD8+ T cells and tumor inhibitions were found in the combinational group compared with CD8+ T cells or sorafenib alone groups. Not only immunosuppressive factors but myeloid derived suppressive cells (MDSCs) and regulatory T cells (Tregs) were decreased in sorafenib-treated group, indicating that augmentation of tumor inhibition and function of CD8+ T cells by serial low doses of sorafenib were via reversing the immunosuppressive microenvironment. These results revealed that the tumor inhibitions of sorafenib not only through eradicating tumor cells but modifying tumor microenvironment, which helps outcomes of ACT significantly. PMID:25333973

  10. Synergistic effects of ascorbate and sorafenib in hepatocellular carcinoma: New insights into ascorbate cytotoxicity.

    PubMed

    Rouleau, Lauren; Antony, Anil Noronha; Bisetto, Sara; Newberg, Andrew; Doria, Cataldo; Levine, Mark; Monti, Daniel A; Hoek, Jan B

    2016-06-01

    We investigated the mechanism of selective ascorbate-induced cytotoxicity in tumor cells, including Hep G2 cells, compared to primary hepatocytes. H2O2 formation was required for ascorbate cytotoxicity, as extracellular catalase treatment protected tumor cells. H2O2 generated by glucose oxidase treatment also caused cell killing, but treatment with a pharmacologic dose (5-20mM) of ascorbate was significantly more cytotoxic at comparable rates of H2O2 production, suggesting that ascorbate enhanced H2O2 cytotoxicity. This was further supported by the finding that ascorbate at a non-cytotoxic dose (1mM) enhanced cell killing caused by glucose oxidase. Consistent with this conclusion, ascorbate treatment caused deregulation of cellular calcium homeostasis, resulting in massive mitochondrial calcium accumulation. Ascorbate acted synergistically with the chemotherapeutic sorafenib in killing Hep G2 cells, but not primary hepatocytes, suggesting adjuvant ascorbate treatment can broaden sorafenib's therapeutic range. Sorafenib caused mitochondrial depolarization and prevented mitochondrial calcium sequestration. Subsequent ascorbate addition further deregulated cellular calcium homeostasis promoting cell death. Additionally, we present the case of a patient with hepatocellular carcinoma (HCC) who had prolonged regression of a rib metastasis upon combination treatment with ascorbate and sorafenib, indicating that these studies have direct clinical relevance. PMID:27036367

  11. TLR3 agonist and Sorafenib combinatorial therapy promotes immune activation and controls hepatocellular carcinoma progression.

    PubMed

    Ho, Victor; Lim, Tong Seng; Lee, Justin; Steinberg, Jeffrey; Szmyd, Radoslaw; Tham, Muly; Yaligar, Jadegoud; Kaldis, Philipp; Abastado, Jean-Pierre; Chew, Valerie

    2015-09-29

    Hepatocellular carcinoma (HCC) is associated with high mortality and the current therapy for advanced HCC, Sorafenib, offers limited survival benefits. Here we assessed whether combining the TLR3 agonist: lysine-stabilized polyinosinic-polycytidylic-acid (poly-ICLC) with Sorafenib could enhance tumor control in HCC. Combinatorial therapy with poly-ICLC and Sorafenib increased apoptosis and reduced proliferation of HCC cell lines in vitro, in association with impaired phosphorylation of AKT, MEK and ERK. In vivo, the combinatorial treatment enhanced control of tumor growth in two mouse models: one transplanted with Hepa 1-6 cells, and the other with liver tumors induced using the Sleeping beauty transposon. Tumor cell apoptosis and host immune responses in the tumor microenvironment were enhanced. Particularly, the activation of local NK cells, T cells, macrophages and dendritic cells was enhanced. Decreased expression of the inhibitory signaling molecules PD-1 and PD-L1 was observed in tumor-infiltrating CD8+ T cells and tumor cells, respectively. Tumor infiltration by monocytic-myeloid derived suppressor cells (Mo-MDSC) was also reduced indicating the reversion of the immunosuppressive tumor microenvironment. Our data demonstrated that the combinatorial therapy with poly-ICLC and Sorafenib enhances tumor control and local immune response hence providing a rationale for future clinical studies. PMID:26287667

  12. Clinical experience and critical evaluation of the role of sorafenib in renal cell carcinoma

    PubMed Central

    Zustovich, Fable; Lombardi, Giuseppe; Pastorelli, Davide; Farina, Patrizia; Bianco, Massimo Dal; De Zorzi, Luca; Palma, Maurizia Dalla; Nicoletto, Ornella; Zagonel, Vittorina

    2011-01-01

    Renal cell carcinoma (RCC) is a common malignancy worldwide with approximately 95,000 new cases per year and ranks as the sixth cause of cancer deaths. Until recently, the slightly active and very toxic cytokines were available for patients with advanced RCC. Advances have been made in understanding the molecular biology of renal cancer. The introduction of targeted agents has led to promising possibilities for treating these highly vascularized tumors. Angiogenesis inhibition is likely to represent the main potential therapeutic target. Sorafenib is an oral multikinase inhibitor with activity against tyrosine kinase receptors that are responsible for blood vessel development and has shown to be active in treating advanced RCC. In this review, we summarize the pharmacology, mode of action, pharmacokinetics, and safety of sorafenib use in therapy for advanced RCC. PMID:24198638

  13. Sorafenib for Hepatocellular Carcinoma: From Randomized Controlled Trials to Clinical Practice.

    PubMed

    Cabibbo, Giuseppe; Petta, Salvatore; Maida, Marcello; Cammà, Calogero

    2015-09-01

    Hepatocellular carcinoma is a challenging malignancy of global importance. It is the sixth most common solid malignancy and the third leading cause of cancer-related death, worldwide. Curative treatments at early stages include liver transplantation, resection and percutaneous ablation, while transarterial chemoembolization can improve survival in patients with intermediate tumor stage. Patients with mild, related symptoms and/or macrovascular invasion or extrahepatic spread are classified under the advanced stage. The standard of care in this group is sorafenib, an inhibitor of Raf kinase and vascular endothelial growth factor receptor, whose effectiveness has been proven by 2 recent randomized controlled trials (RCTs). The aim of this brief review is to highlight the main concerns and pitfalls and to analyze the recent data of literature regarding the efficacy and the management of sorafenib therapy from RCTs to real practice. PMID:26398633

  14. Selective Serotonin–norepinephrine Reuptake Inhibitors-induced Takotsubo Cardiomyopathy

    PubMed Central

    Vasudev, Rahul; Rampal, Upamanyu; Patel, Hiten; Patel, Kunal; Bikkina, Mahesh; Shamoon, Fayez

    2016-01-01

    Context: Takotsubo translates to “octopus pot” in Japanese. Takotsubo cardiomyopathy (TTC) is characterized by a transient regional systolic dysfunction of the left ventricle. Catecholamine excess is the one most studied and favored theories explaining the pathophysiology of TTC. Case Report: We present the case of a 52-year-old Hispanic female admitted for venlafaxine-induced TTC with a review literature on all the cases of Serotonin–norepinephrine reuptake inhibitors (SNRI)-associated TTC published so far. Conclusion: SNRI inhibit the reuptake of catecholamines into the presynaptic neuron, resulting in a net gain in the concentration of epinephrine and serotonin in the neuronal synapses and causing iatrogenic catecholamine excess, ultimately leading to TTC. PMID:27583240

  15. Inhibitors of Histone Deacetylases Attenuate Noise-Induced Hearing Loss.

    PubMed

    Chen, Jun; Hill, Kayla; Sha, Su-Hua

    2016-08-01

    Loss of auditory sensory hair cells is the major pathological feature of noise-induced hearing loss (NIHL). Currently, no established clinical therapies for prevention or amelioration of NIHL are available. The absence of treatments is due to our lack of a comprehensive understanding of the molecular mechanisms underlying noise-induced damage. Our previous study indicates that epigenetic modification of histones alters hair cell survival. In this study, we investigated the effect of noise exposure on histone H3 lysine 9 acetylation (H3K9ac) in the inner ear of adult CBA/J mice and determined if inhibition of histone deacetylases by systemic administration of suberoylanilide hydroxamic acid (SAHA) could attenuate NIHL. Our results showed that H3K9ac was decreased in the nuclei of outer hair cells (OHCs) and marginal cells of the stria vascularis in the basal region after exposure to a traumatic noise paradigm known to induce permanent threshold shifts (PTS). Consistent with these results, levels of histone deacetylases 1, 2, and 3 (HDAC1, HDAC2 and HDAC3) were increased predominately in the nuclei of cochlear cells. Silencing of HDAC1, HDAC2, or HDAC3 with siRNA reduced the expression of the target HDAC in OHCs, but did not attenuate noise-induced PTS, whereas treatment with the pan-HDAC inhibitor SAHA, also named vorinostat, reduced OHC loss, and attenuated PTS. These findings suggest that histone acetylation is involved in the pathogenesis of noise-induced OHC death and hearing loss. Pharmacological targeting of histone deacetylases may afford a strategy for protection against NIHL. PMID:27095478

  16. MG132, a proteasome inhibitor, induces apoptosis in tumor cells.

    PubMed

    Guo, Na; Peng, Zhilan

    2013-03-01

    The balance between cell proliferation and apoptosis is critical for normal development and for the maintenance of homeostasis in adult organisms. Disruption of this balance has been implicated in a large number of disease processes, ranging from autoimmunity and neurodegenerative disorders to cancer. The ubiquitin-proteasome pathway, responsible for mediating the majority of intracellular proteolysis, plays a crucial role in the regulation of many normal cellular processes, including the cell cycle, differentiation and apoptosis. Apoptosis in cancer cells is closely connected with the activity of ubiquitin-proteasome pathway. The peptide-aldehyde proteasome inhibitor MG132 (carbobenzoxyl-L-leucyl-L-leucyl-L-leucine) induces the apoptosis of cells by a different intermediary pathway. Although the pathway of induction of apoptosis is different, it plays a crucial role in anti-tumor treatment. There are many cancer-related molecules in which the protein levels present in cells are regulated by a proteasomal pathway; for example, tumor inhibitors (P53, E2A, c-Myc, c-Jun, c-Fos), transcription factors (transcription factor nuclear factor-kappa B, IκBα, HIFI, YYI, ICER), cell cycle proteins (cyclin A and B, P27, P21, IAP1/3), MG132 induces cell apoptosis through formation of reactive oxygen species or the upregulation and downregulation of these factors, which is ultimately dependent upon the activation of the caspase family of cysteine proteases. In this article we review the mechanism of the induction of apoptosis in order to provide information required for research. PMID:22897979

  17. 2-Deoxy-d-Glucose Can Complement Doxorubicin and Sorafenib to Suppress the Growth of Papillary Thyroid Carcinoma Cells

    PubMed Central

    Wang, Shuo-Yu; Wei, Yau-Huei; Shieh, Dar-Bin; Lin, Li-Ling; Cheng, Shih-Ping; Wang, Pei-Wen; Chuang, Jiin-Haur

    2015-01-01

    Tumor cells display a shift in energy metabolism from oxidative phosphorylation to aerobic glycolysis. A subset of papillary thyroid carcinoma (PTC) is refractory to surgery and radioactive iodine ablation. Doxorubicin and sorafenib are the drugs of choice for treating advanced thyroid cancer but both induce adverse effects. In this study, we assessed the anti-cancer activity of 2-deoxy-d-glucose (2-DG) alone and in combination with doxorubicin or sorafenib in PTC cell lines with (BCPAP) and without (CG3) the BRAFV600E mutation. BCPAP cells were more glycolytic than CG3 cells, as evidenced by their higher extracellular l-lactate production, lower intracellular ATP level, lower oxygen consumption rate (OCR), and lower ratio of OCR/extracellular acidification rate. However, dose-dependent reduction in cell viability, intracellular ATP depletion, and extracellular l-lactate production were observed after 2-DG treatment. Regression analysis showed that cell growth in both cell lines was dependent on ATP generation. 2-DG increased the chemosensitivity of BCPAP and CG3 cell lines to doxorubicin and sorafenib. These results demonstrate that the therapeutic effects of low combined doses of 2-DG and doxorubicin or sorafenib are similar to those of high doses of doxorubicin or sorafenib alone in PTC cell lines regardless of the BRAFV600E mutation. PMID:26134286

  18. Alternative Mammalian Target of Rapamycin (mTOR) Signal Activation in Sorafenib-resistant Hepatocellular Carcinoma Cells Revealed by Array-based Pathway Profiling*

    PubMed Central

    Masuda, Mari; Chen, Wei-Yu; Miyanaga, Akihiko; Nakamura, Yuka; Kawasaki, Kumiko; Sakuma, Tomohiro; Ono, Masaya; Chen, Chi-Long; Honda, Kazufumi; Yamada, Tesshi

    2014-01-01

    Sorafenib is a multi-kinase inhibitor that has been proven effective for the treatment of unresectable hepatocellular carcinoma (HCC). However, its precise mechanisms of action and resistance have not been well established. We have developed high-density fluorescence reverse-phase protein arrays and used them to determine the status of 180 phosphorylation sites of signaling molecules in the 120 pathways registered in the NCI-Nature curated database in 23 HCC cell lines. Among the 180 signaling nodes, we found that the level of ribosomal protein S6 phosphorylated at serine residue 235/236 (p-RPS6 S235/236) was most significantly correlated with the resistance of HCC cells to sorafenib. The high expression of p-RPS6 S235/236 was confirmed immunohistochemically in biopsy samples obtained from HCC patients who responded poorly to sorafenib. Sorafenib-resistant HCC cells showed constitutive activation of the mammalian target of rapamycin (mTOR) pathway, but whole-exon sequencing of kinase genes revealed no evident alteration in the pathway. p-RPS6 S235/236 is a potential biomarker that predicts unresponsiveness of HCC to sorafenib. The use of mTOR inhibitors may be considered for the treatment of such tumors. PMID:24643969

  19. Valproic Acid and Other HDAC Inhibitors Induce Microglial Apoptosis and Attenuate Lipopolysaccharide- induced Dopaminergic Neurotoxicity

    PubMed Central

    Chen, Po See; Wang, Chao-Chuan; Bortner, Carl D.; Peng, Giia-Sheun; Wu, Xuefei; Pang, Hao; Lu, Ru-Band; Gean, Po-Wu; Chuang, De-Maw; Hong, Jau-Shyong

    2009-01-01

    Valproic acid (VPA), a widely prescribed drug for seizures and bipolar disorder, has been shown to be an inhibitor of histone deacetylase (HDAC). Our previous study has demonstrated that VPA pretreatment reduces lipopolysaccharide (LPS)-induced dopaminergic (DA) neurotoxicity through the inhibition of microglia over-activation. The aim of this study was to determine the mechanism underlying VPA-induced attenuation of microglia over-activation. Other HDAC inhibitors (HDACIs) were compared with VPA for their effects on microglial activity. We found that VPA induced apoptosis of microglia cells in a time and concentration-dependent manner. VPA-treated microglial cells showed typical apoptotic hallmarks including phosphatidylserine externalization, chromatin condensation and DNA fragmentation. Further studies revealed that trichostatin A (TSA) and sodium butyrate (SB), two structurally dissimilar HDACIs, also induced microglial apoptosis. The apoptosis of microglia was accompanied by the disruption of mitochondrial membrane potential and the enhancement of acetylation levels of the histone H3 protein. Moreover, pretreatment with SB or TSA caused a robust decrease in LPS-induced pro-inflammatory responses and protected DA neurons from damage in mesencephalic neuron-glia cultures. Taken together, our results shed light on a novel mechanism whereby HDACIs induce neuroprotection and underscore the potential utility of HDACIs in preventing inflammation-related neurodegenerative disorders such as Parkinson’s disease. PMID:17850978

  20. Effects of Sorafenib on C-Terminally Truncated Androgen Receptor Variants in Human Prostate Cancer Cells

    PubMed Central

    Zengerling, Friedemann; Streicher, Wolfgang; Schrader, Andres J.; Schrader, Mark; Nitzsche, Bianca; Cronauer, Marcus V.; Höpfner, Michael

    2012-01-01

    Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa) is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR). A putative mechanism allowing prostate cancer (PCa) cells to grow under low levels of androgens, is the expression of constitutively active, C-terminally truncated AR lacking the AR-ligand binding domain (LBD). Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa. PMID:23109869

  1. Effects of sorafenib on C-terminally truncated androgen receptor variants in human prostate cancer cells.

    PubMed

    Zengerling, Friedemann; Streicher, Wolfgang; Schrader, Andres J; Schrader, Mark; Nitzsche, Bianca; Cronauer, Marcus V; Höpfner, Michael

    2012-01-01

    Recent evidence suggests that the development of castration resistant prostate cancer (CRPCa) is commonly associated with an aberrant, ligand-independent activation of the androgen receptor (AR). A putative mechanism allowing prostate cancer (PCa) cells to grow under low levels of androgens, is the expression of constitutively active, C-terminally truncated AR lacking the AR-ligand binding domain (LBD). Due to the absence of a LBD, these receptors, termed ARΔLBD, are unable to respond to any form of anti-hormonal therapies. In this study we demonstrate that the multikinase inhibitor sorafenib inhibits AR as well as ARΔLBD-signalling in CRPCa cells. This inhibition was paralleled by proteasomal degradation of the AR- and ARΔLBD-molecules. In line with these observations, maximal antiproliferative effects of sorafenib were achieved in AR and ARΔLBD-positive PCa cells. The present findings warrant further investigations on sorafenib as an option for the treatment of advanced AR-positive PCa. PMID:23109869

  2. Novel sorafenib-based structural analogues: in-vitro anticancer evaluation of t-MTUCB and t-AUCMB.

    PubMed

    Wecksler, Aaron T; Hwang, Sung Hee; Wettersten, Hiromi I; Gilda, Jennifer E; Patton, Amy; Leon, Leonardo J; Carraway, Kermit L; Gomes, Aldrin V; Baar, Keith; Weiss, Robert H; Hammock, Bruce D

    2014-04-01

    In the current work, we carried out a mechanistic study on the cytotoxicity of two compounds, trans-4-[4-(3-adamantan-1-yl-ureido)-cyclohexyloxy]-N-methyl-benzamide (t-AUCMB) and trans-N-methyl-4-{4-[3-(4-trifluoromethoxy-phenyl)-ureido]-cyclohexyloxy}-benzamide (t-MTUCB), that are structurally similar to sorafenib. These compounds show strong cytotoxic responses in various cancer cell lines, despite significant differences in the induction of apoptotic events such as caspase activation and lactate dehydrogenase release in hepatoma cells. Both compounds induce autophagosome formation and LC3I cleavage, but there was little observable effect on mTORC1 or the downstream targets, S6K1 and 4E-binding protein. In addition, there was an increase in the activity of upstream signaling through the IRS1/PI3K/Akt-signaling pathway, suggesting that, unlike sorafenib, both compounds induce mammalian target of rapamycin (mTOR)-independent autophagy. The autophagy observed correlates with mitochondrial membrane depolarization, apoptosis-inducing factor release, and oxidative stress-induced glutathione depletion. However, there were no observable changes in the endoplasmic reticulum-stress markers such as binding immunoglobulin protein, inositol-requiring enzyme-α, phosphorylated eukaryotic initiation factor 2, and the lipid peroxidation marker, 4-hydroxynonenal, suggesting endoplasmic reticulum-independent oxidative stress. Finally, these compounds do not have the multikinase inhibitory activity of sorafenib, which may be reflected in their difference in the ability to halt cell cycle progression compared with sorafenib. Our findings indicate that both compounds have anticancer effects comparable with sorafenib in multiple cell lines, but they induce significant differences in apoptotic responses and appear to induce mTOR-independent autophagy. t-AUCMB and t-MTUCB represent novel chemical probes that are capable of inducing mTOR-independent autophagy and apoptosis to differing

  3. PHY906(KD018), an adjuvant based on a 1800-year-old Chinese medicine, enhanced the anti-tumor activity of Sorafenib by changing the tumor microenvironment

    PubMed Central

    Lam, Wing; Jiang, Zaoli; Guan, Fulan; Huang, Xiu; Hu, Rong; Wang, Jing; Bussom, Scott; Liu, Shwu-Huey; Zhao, Hongyu; Yen, Yun; Cheng, Yung-Chi

    2015-01-01

    PHY906 (KD018) is a four-herb Chinese Medicine Formula. It has been shown to potentially enhance the therapeutic indices of different class anticancer agents in vivo. Here, PHY906 is reported to enhance the anti-tumor activity of Sorafenib in nude mice bearing HepG2 xenografts. Among the four herbal ingredients of PHY906, Scutellaria baicalensis Georgi (S) and Paeonia lactiflora Pall (P) are required; however, S plays a more important role than P in increasing tumor apoptosis induced by Sorafenib with an increase of mouse(m)FasL and human(h)FasR expression. PHY906 may potentiate Sorafenib action by increasing hMCP1 expression and enhancing infiltration of macrophages into tumors with a higher M1/M2 (tumor rejection) signature expression pattern, as well as affect autophagy by increasing AMPKα-P and ULK1-S555-P of tumors. Depletion of macrophage could counteract PHY906 to potentiate the anti-tumor activity of Sorafenib. It was reported that tumor cells with higher levels of ERK1/2-P are more susceptible to Sorafenib, and the S component of PHY906 may increase ERK1/2-P via inhibition of ERK1/2 phosphatase in HepG2 tumors. PHY906 may potentiate the anti-hepatoma activity of Sorafenib by multiple mechanisms targeting on the inflammatory state of microenvironment of tumor tissue through two major ingredients (P and S) of PHY906. PMID:25819872

  4. A novel p21 attenuator which is structurally related to sorafenib

    PubMed Central

    Wettersten, Hiromi I.; Hee Hwang, Sung; Li, Cuiwen; Shiu, Eunice Y.; Wecksler, Aaron T.; Hammock, Bruce D.; Weiss, Robert H.

    2013-01-01

    p21 is a member of the cyclin kinase inhibitor family of proteins and plays pivotal roles in cellular proliferation as well as in the regulation of apoptosis, and thus has diverse functions in diseases as varied as cancer and atherosclerosis. In light of its pleiotropic effects and potential clinical relevance, new methods of attenuation of p21 protein levels by selective inhibitors are therefore powerful tools to probe malignant, infectious and other diseases. Here we introduce a novel p21 attenuator, UC2288, which possesses consistent and relatively selective activity for p21. UC2288 was synthesized based on the chemical model of sorafenib, a multikinase inhibitor that also attenuates p21, but unlike sorafenib, UC2288 did not inhibit Raf kinases or alter p-ERK protein levels. UC2288 decreased p21 mRNA expression independently of p53, and attenuated p21 protein levels with minimal effect on p21 protein stability. In addition, UC2288 inhibits cell growth in the kidney cancer cell lines (GI50 = approximately 10 µM) as well as multiple other cancer cell lines. Thus, this novel p21 inhibitor will be indispensable for exploring the function of p21, and upon further study may be translatable to the clinic. PMID:23298903

  5. Inhibitors

    MedlinePlus

    ... Community Counts Blood Safety Inhibitors Articles & Key Findings Free Materials Videos Starting the Conversation Playing it Safe A Look at Hemophilia Joint Range of Motion My Story Links to Other Websites ...

  6. Risk of mucocutaneous toxicities in patients with solid tumors treated with sorafenib: an updated systematic review and meta-analysis.

    PubMed

    Abdel-Rahman, Omar; Fouad, Mona

    2014-06-01

    We performed a systematic review and meta-analysis of mucocutaneous toxicities associated with sorafenib, an oral multi tyrosine kinase inhibitor. Eligible studies included randomized Phase II and III trials of patients with solid tumors on sorafenib daily describing events of hand foot skin reaction, skin rash, alopecia, stomatitis or pruritis. Patients treated with sorafenib had a significantly increased risk of all-grade mucocutaneous toxicities. The RR of all-grade hand foot skin reaction, skin rash, alopecia, stomatitis and pruritis were 4.33 (95% CI: 3.06-6.14), 2.67 (95% CI: 1.86-3.83), 3.93 (95% CI: 2.07-7.45), 2.9 (95% CI: 2.26-3.73), 2.29 (95% CI: 1.87-3.03); respectively. Exploratory subgroup analysis showed no effect of tumor types or treatment regimen (monotherapy versus combination) on the RR of mucocutaneous toxicities. Our meta-analysis has demonstrated that sorafenib is associated with a higher risk of developing all grade mucocutaneous toxicities compared with control. PMID:24666215

  7. Proton pump inhibitor-induced exfoliative dermatitis: A case report

    PubMed Central

    QIU, ZHIHONG; LIU, HONGTAO; HE, LIEN; MA, YINLING; SONG, HAOJING; BAI, WANJUN; YU, MEILING

    2016-01-01

    A 74-year-old female patient was admitted to hospital following a road accident with pains in the chest, abdomen, waist, back, nose, left wrist and lower limbs. After 1 week, the patient presented with gastrointestinal bleeding, and thus was treated with protein pump inhibitors (PPIs), including lansoprazole, esomeprazole and omeprazole enteric-coated tablets, in order to inhibit acid secretion and attenuate bleeding. However, the patient developed skin rashes on the chest and right lower limb and foot 28 days following treatment initiation. The skin rashes spread and ulcerated after 3 days, and were associated with tracheal mucosal injury and hemoptysis. Subsequently, treatment of the patient with PPIs was terminated, after which the tracheal hemoptysis and skin rashes markedly improved. In addition, no new skin rashes appeared following termination of the PPI treatment. In the present case, long-term treatment of an elderly patient with PPIs may have induced exfoliative dermatitis, due to hepatic ischemia, hypoxia and acute renal failure, which may have decreased the metabolism of PPIs, resulting in the accumulation of PPI metabolites. PMID:26893644

  8. Saturable absorption of sorafenib in patients with solid tumors: a population model.

    PubMed

    Hornecker, Marilyne; Blanchet, Benoit; Billemont, Bertrand; Sassi, Hind; Ropert, Stanislas; Taieb, Fabrice; Mir, Olivier; Abbas, Halim; Harcouet, Laura; Coriat, Romain; Dauphin, Alain; Goldwasser, François; Tod, Michel

    2012-10-01

    Sorafenib is an oral tyrosine kinase inhibitor approved for the treatment of advanced renal cell carcinoma and hepatocellular carcinoma. By using a population approach, this study aimed to characterise its pharmacokinetics. Plasma concentration-time data (n = 372) from 71 patients under sorafenib were analysed using nonlinear mixed-effect modelling to estimate population pharmacokinetic parameters, as well as relationships between these parameters and different covariates (demographic, biological). Simulations were done to compare different daily dosing regimens in a context of dose-escalation. A 1-compartment model with saturated absorption, first-order intestinal loss and elimination best described the pharmacokinetics of sorafenib. Absolute bioavailability significantly dropped with increasing daily doses of sorafenib. AUC increased less than proportionally with increasing doses [47.3 (41.3-63.3), 60.3 (56.3-64.4), 71.4 (51.3-99.1), 75.9 (45.5-100.9) mg/L.h for 400, 800, 1,200 and 1,600 mg/day, respectively]. According to the simulations, dividing the daily dose in three or four doses for daily dose >800 mg would significantly increase AUC compared with a twice daily dosing regimen (101.7 vs 81.6 mg/L.h for 400 mg q8h and 600 mg q12h respectively; 131.6 vs 91.5 mg/L.h for 400 mg q6h and 800 mg q12h, respectively). Thrice daily regimen may be most suitable in a context of dose-escalation (>800 mg/day) in non-responders to standard-dosing regimen. PMID:22006162

  9. Sorafenib in the treatment of thyroid cancer.

    PubMed

    Ferrari, Silvia Martina; Politti, Ugo; Spisni, Roberto; Materazzi, Gabriele; Baldini, Enke; Ulisse, Salvatore; Miccoli, Paolo; Antonelli, Alessandro; Fallahi, Poupak

    2015-01-01

    Sorafenib has been evaluated in several Phase II and III studies in patients with locally advanced/metastatic radioactive iodine-refractory differentiated thyroid carcinomas (DTCs), reporting partial responses, stabilization of the disease and improvement of progression-free survival. Best responses were observed in lung metastases and minimal responses in bone lesions. On the basis of these studies, sorafenib was approved for the treatment of metastatic DTC in November 2013. Few studies suggested that reduction of thyroglobulin levels, or of average standardized uptake value at the fluorodeoxyglucose-PET, could be helpful for the identification of responding patients; but further studies are needed to confirm these results. Tumor genetic marker levels did not have any prognostic or predictive role in DTC patients.The most common adverse events observed included skin toxicity and gastrointestinal and constitutional symptoms. Encouraging results have also been observed in patients with medullary thyroid cancer. Many studies are ongoing to evaluate the long-term efficacy and tolerability of sorafenib in DTC patients. PMID:26152651

  10. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

    SciTech Connect

    Meng, Zhen; Gan, Ye-Hua

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. - Highlights: • COX-2 inhibitor, celecoxib, could enhance radiosensitization. • Radiation induced PTEN inactivation (phosphorylation) and AKT activation. • COX-2 inhibitor induced PTEN expression and activation, and inactivated AKT. • COX-2 inhibitor enhanced radiosensitization through activating PTEN.

  11. Novel Sorafenib-Based Structural Analogues: In Vitro Anticancer Evaluation of t-MTUCB and t-AUCMB

    PubMed Central

    Wecksler, Aaron T.; Hwang, Sung Hee; Wettersten, Hiromi I.; Gilda, Jennifer E.; Patton, Amy; Leon, Leonardo J.; Carraway, Kermit L.; Gomes, Aldrin V.; Baar, Keith; Weiss, Robert H.; Hammock, Bruce D.

    2014-01-01

    In the current study, we performed a mechanistic study on the cytotoxicity of two compounds, t-AUCMB and t-MTUCB, that are structurally similar to sorafenib. These compounds display strong cytotoxic responses in various cancer cell lines, despite significant differences in the induction of apoptotic events such as caspase activation and lactate dehydrogenase release in hepatoma cells. Both compounds induce autophagosome formation and LC3I cleavage, but there was little observable effect on mTORC1 or the downstream targets, S6K1 and 4E-BP1. In addition, there was an increase in activity of upstream signaling through the IRS1/PI3K/Akt signaling pathway, suggesting that unlike sorafenib, both compounds induce mTOR-independent autophagy. The observed autophagy correlates with mitochondrial membrane depolarization, AIF release, and oxidative stress-induced glutathione depletion. However, there were no observable changes in the ER-stress markers such as, Bip, IREα, p-eIP2, and the lipid peroxidation marker, 4-HNE, suggesting ER-independent oxidative stress. Finally, these compounds do not possess the multikinase inhibitory activity of sorafenib, which may be reflected in their difference in ability to halt cell cycle progression compared to sorafenib. Our findings indicate that both compounds have anti-cancer effects comparable to sorafenib in multiple cell line, but they induce significant differences in apoptotic responses and appear to induce mTOR-independent autophagy. t-AUCMB and t-MTUCB, represent novel chemical probes that are capable of inducing mTOR-independent autophagy and apoptosis to differing degrees, and thus may be potential tools for further understanding the link between these two cellular stress responses. PMID:24525589

  12. The Limonoids TS3 and Rubescin E Induce Apoptosis in Human Hepatoma Cell Lines and Interfere with NF-κB Signaling

    PubMed Central

    Lange, Nicole; Tontsa, Armelle Tsamo; Wegscheid, Claudia; Mkounga, Pierre; Nkengfack, Augustin Ephrem; Sass, Gabriele; Tiegs, Gisa

    2016-01-01

    Hepatocellular carcinoma (HCC) is extremely resistant towards pharmacological therapy. To date, the multi-kinase inhibitor Sorafenib is the only available therapeutic agent with the potential to prolong patient survival. Using the human hepatoma cell lines HepG2 and Huh7, we analyzed anti-cancer activities of 6 purified havanensin type limonoids isolated from the traditional African medicinal plant Trichilia rubescens Oliv. Our results show that two of the compounds, TR4 (TS3) and TR9 (Rubescin E) reduced hepatoma cell viability, but not primary hepatocyte viability, at TC50s of 5 to 10 μM. These were significantly lower than the TC50s for Sorafenib, the histone deacetylase inhibitor SAHA or 5-Fluoruracil. In comparison, TR3 (Rubescin D), a limonoid isolated in parallel and structurally highly similar to TR4 and TR9, did not interfere with hepatoma cell viability. Both, TR4 and TR9, but not TR3, induced apoptosis in hepatoma cells and interfered with NF-κB activation. TR4 as well as TR9 significantly supported anti-cancer activities of Sorafenib. In summary, the limonoids TR4 and TR9 exhibit anti-cancer activities and support Sorafenib effects in vitro, having the potential to support future HCC therapy. PMID:27518192

  13. The Limonoids TS3 and Rubescin E Induce Apoptosis in Human Hepatoma Cell Lines and Interfere with NF-κB Signaling.

    PubMed

    Lange, Nicole; Tontsa, Armelle Tsamo; Wegscheid, Claudia; Mkounga, Pierre; Nkengfack, Augustin Ephrem; Loscher, Christine; Sass, Gabriele; Tiegs, Gisa

    2016-01-01

    Hepatocellular carcinoma (HCC) is extremely resistant towards pharmacological therapy. To date, the multi-kinase inhibitor Sorafenib is the only available therapeutic agent with the potential to prolong patient survival. Using the human hepatoma cell lines HepG2 and Huh7, we analyzed anti-cancer activities of 6 purified havanensin type limonoids isolated from the traditional African medicinal plant Trichilia rubescens Oliv. Our results show that two of the compounds, TR4 (TS3) and TR9 (Rubescin E) reduced hepatoma cell viability, but not primary hepatocyte viability, at TC50s of 5 to 10 μM. These were significantly lower than the TC50s for Sorafenib, the histone deacetylase inhibitor SAHA or 5-Fluoruracil. In comparison, TR3 (Rubescin D), a limonoid isolated in parallel and structurally highly similar to TR4 and TR9, did not interfere with hepatoma cell viability. Both, TR4 and TR9, but not TR3, induced apoptosis in hepatoma cells and interfered with NF-κB activation. TR4 as well as TR9 significantly supported anti-cancer activities of Sorafenib. In summary, the limonoids TR4 and TR9 exhibit anti-cancer activities and support Sorafenib effects in vitro, having the potential to support future HCC therapy. PMID:27518192

  14. Cerebellar stroke in a low cardiovascular risk patient associated with sorafenib treatment for fibrolamellar hepatocellular carcinoma

    PubMed Central

    Vandewynckel, Yves-Paul; Geerts, Anja; Verhelst, Xavier; Van Vlierberghe, Hans

    2014-01-01

    Key Clinical Message Sorafenib is the standard treatment of hepatocellular carcinoma (HCC). However, fibrolamellar HCC was not included in sorafenib trials. The case is a 26-year-old man with fibrolamellar HCC, who had a cerebrovascular accident (CVA) while being treated with sorafenib. This illustrates a probable relationship between use of sorafenib and CVA in low cardiovascular risk patients. PMID:25356226

  15. Behavioral destabilization induced by the selective serotonin reuptake inhibitor fluoxetine

    PubMed Central

    2011-01-01

    Background Selective serotonin reuptake inhibitors (SSRIs) are widely used to treat mood and anxiety disorders. However, neuronal bases for both beneficial and adverse effects of SSRIs remain poorly understood. We have recently shown that the SSRI fluoxetine can reverse the state of maturation of hippocampal granule cells in adult mice. The granule cell "dematuration" is induced in a large population of granule cells, and greatly changes functional and physiological properties of these cells. Here we show that this unique form of neuronal plasticity is correlated with a distinct change in behavior of mice. Results We chronically treated adult male mice with fluoxetine, and examined its effect on several forms of behavior of mice. During fluoxetine treatments, mice showed a marked increase in day-to-day fluctuations of home cage activity levels that was characterized by occasional switching between hypoactivity and hyperactivity within a few days. This destabilized cage activity was accompanied by increased anxiety-related behaviors and could be observed up to 4 weeks after withdrawal from fluoxetine. As reported previously, the granule cell dematuration by fluoxetine includes a reduction of synaptic facilitation at the granule cell output, mossy fiber, synapse to the juvenile level. Mossy fiber synaptic facilitation examined electrophysiologically in acute hippocampal slices also remained suppressed after fluoxetine withdrawal and significantly correlated with the fluctuation of cage activity levels in individual mice. Furthermore, in mice lacking the 5-HT4 receptor, in which the granule cell dematuration has been shown to be attenuated, fluoxetine had no significant effect on the fluctuation of cage activity levels. Conclusions Our results demonstrate that the SSRI fluoxetine can induce marked day-to-day changes in activity levels of mice in the familiar environment, and that the dematuration of the hippocampal granule cells is closely associated with the

  16. Evaluation of aspirin metabolites as inhibitors of hypoxia-inducible factor hydroxylases.

    PubMed

    Lienard, Benoit M; Conejo-García, Ana; Stolze, Ineke; Loenarz, Christoph; Oldham, Neil J; Ratcliffe, Peter J; Schofield, Christopher J

    2008-12-21

    Known and potential aspirin metabolites were evaluated as inhibitors of oxygen-sensing hypoxia-inducible transcription factor (HIF) hydroxylases; some of the metabolites were found to stabilise HIF-alpha in cells. PMID:19048166

  17. Selective Serotonin Reuptake Inhibitor-Induced Sexual Dysfunction in Adolescents: A Review.

    ERIC Educational Resources Information Center

    Scharko, Alexander M.

    2004-01-01

    Objective: To review the existing literature on selective serotonin reuptake inhibitor (SSRI)-induced sexual dysfunction in adolescents. Method: A literature review of SSRI-induced adverse effects in adolescents focusing on sexual dysfunction was done. Nonsexual SSRI-induced adverse effects were compared in adult and pediatric populations.…

  18. Arsenic toxicity induced endothelial dysfunction and dementia: Pharmacological interdiction by histone deacetylase and inducible nitric oxide synthase inhibitors

    SciTech Connect

    Sharma, Bhupesh Sharma, P.M.

    2013-11-15

    Arsenic toxicity has been reported to damage all the major organs including the brain and vasculature. Dementia including Alzheimer's disease (AD) and vascular dementia (VaD) are posing greater risk to the world population as it is now increasing at a faster rate. We have investigated the role of sodium butyrate, a selective histone deacetylase (HDAC) inhibitor and aminoguanidine, a selective inducible nitric oxide synthase (iNOS) inhibitor in pharmacological interdiction of arsenic toxicity induced vascular endothelial dysfunction and dementia in rats. Arsenic toxicity was done by administering arsenic drinking water to rats. Morris water-maze (MWM) test was used for assessment of learning and memory. Endothelial function was assessed using student physiograph. Oxidative stress (aortic superoxide anion, serum and brain thiobarbituric acid reactive species, brain glutathione) and nitric oxide levels (serum nitrite/nitrate) were also measured. Arsenic treated rats have shown impairment of endothelial function, learning and memory, reduction in serum nitrite/nitrate and brain GSH levels along with increase in serum and brain TBARS. Sodium butyrate as well as aminoguanidine significantly convalesce arsenic induced impairment of learning, memory, endothelial function, and alterations in various biochemical parameters. It may be concluded that arsenic induces endothelial dysfunction and dementia, whereas, sodium butyrate, a HDAC inhibitor as well as aminoguanidine, a selective iNOS inhibitor may be considered as potential agents for the management of arsenic induced endothelial dysfunction and dementia. - Highlights: • As has induced endothelial dysfunction (Edf) and vascular dementia (VaD). • As has increased oxidative stress, AChE activity and decreased serum NO. • Inhibitors of HDAC and iNOS have attenuated As induced Edf and VaD. • Both the inhibitors have attenuated As induced biochemical changes. • Inhibitor of HDAC and iNOS has shown good potential in

  19. Resistance to BRAF inhibitors induces glutamine dependency in melanoma cells

    PubMed Central

    Baenke, Franziska; Chaneton, Barbara; Smith, Matthew; Van Den Broek, Niels; Hogan, Kate; Tang, Haoran; Viros, Amaya; Martin, Matthew; Galbraith, Laura; Girotti, Maria R.; Dhomen, Nathalie; Gottlieb, Eyal; Marais, Richard

    2016-01-01

    BRAF inhibitors can extend progression-free and overall survival in melanoma patients whose tumors harbor mutations in BRAF. However, the majority of patients eventually develop resistance to these drugs. Here we show that BRAF mutant melanoma cells that have developed acquired resistance to BRAF inhibitors display increased oxidative metabolism and increased dependency on mitochondria for survival. Intriguingly, the increased oxidative metabolism is associated with a switch from glucose to glutamine metabolism and an increased dependence on glutamine over glucose for proliferation. We show that the resistant cells are more sensitive to mitochondrial poisons and to inhibitors of glutaminolysis, suggesting that targeting specific metabolic pathways may offer exciting therapeutic opportunities to treat resistant tumors, or to delay emergence of resistance in the first-line setting. PMID:26365896

  20. BET inhibitors induce apoptosis through a MYC independent mechanism and synergise with CDK inhibitors to kill osteosarcoma cells

    PubMed Central

    Baker, Emma K; Taylor, Scott; Gupte, Ankita; Sharp, Phillip P; Walia, Mannu; Walsh, Nicole C; Zannettino, Andrew CW; Chalk, Alistair M; Burns, Christopher J; Walkley, Carl R

    2015-01-01

    Osteosarcoma (OS) survival rates have plateaued in part due to a lack of new therapeutic options. Here we demonstrate that bromodomain inhibitors (BETi), JQ1, I-BET151, I-BET762, exert potent anti-tumour activity against primary and established OS cell lines, mediated by inhibition of BRD4. Strikingly, unlike previous observations in long-term established human OS cell lines, the antiproliferative activity of JQ1 in primary OS cells was driven by the induction of apoptosis, not cell cycle arrest. In further contrast, JQ1 activity in OS was mediated independently of MYC downregulation. We identified that JQ1 suppresses the transcription factor FOSL1 by displacement of BRD4 from its locus. Loss of FOSL1 phenocopied the antiproliferative effects of JQ1, identifying FOSL1 suppression as a potential novel therapeutic approach for OS. As a monotherapy JQ1 demonstrated significant anti-tumour activity in vivo in an OS graft model. Further, combinatorial treatment approaches showed that JQ1 increased the sensitivity of OS cells to doxorubicin and induced potent synergistic activity when rationally combined with CDK inhibitors. The greater level of activity achieved with the combination of BETi with CDK inhibitors demonstrates the efficacy of this combination therapy. Taken together, our studies show that BET inhibitors are a promising new therapeutic for OS. PMID:25944566

  1. Salicylic Acid Inhibits Synthesis of Proteinase Inhibitors in Tomato Leaves Induced by Systemin and Jasmonic Acid.

    PubMed Central

    Doares, S. H.; Narvaez-Vasquez, J.; Conconi, A.; Ryan, C. A.

    1995-01-01

    Salicylic acid (SA) and acetylsalicylic acid (ASA), previously shown to inhibit proteinase inhibitor synthesis induced by wounding, oligouronides (H.M. Doherty, R.R. Selvendran, D.J. Bowles [1988] Physiol Mol Plant Pathol 33: 377-384), and linolenic acid (H. Pena-Cortes, T. Albrecht, S. Prat, E.W. Weiler, L. Willmitzer [1993] Planta 191: 123-128), are shown here to be potent inhibitors of systemin-induced and jasmonic acid (JA)-induced synthesis of proteinase inhibitor mRNAs and proteins. The inhibition by SA and ASA of proteinase inhibitor synthesis induced by systemin and JA, as well as by wounding and oligosaccharide elicitors, provides further evidence that both oligosaccharide and polypeptide inducer molecules utilize the octadecanoid pathway to signal the activation of proteinase inhibitor genes. Tomato (Lycopersicon esculentum) leaves were pulse labeled with [35S]methionine, followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and the inhibitory effects of SA are shown to be specific for the synthesis of a small number of JA-inducible proteins that includes the proteinase inhibitors. Previous results have shown that SA inhibits the conversion of 13S-hydroperoxy linolenic acid to 12-oxo-phytodienoic acid, thereby inhibiting the signaling pathway by blocking synthesis of JA. Here we report that the inhibition of synthesis of proteinase inhibitor proteins and mRNAs by SA in both light and darkness also occurs at a step in the signal transduction pathway, after JA synthesis but preceding transcription of the inhibitor genes. PMID:12228577

  2. DPP IV inhibitor blocks mescaline-induced scratching and amphetamine-induced hyperactivity in mice.

    PubMed

    Lautar, Susan L; Rojas, Camilo; Slusher, Barbara S; Wozniak, Krystyna M; Wu, Ying; Thomas, Ajit G; Waldon, Daniel; Li, William; Ferraris, Dana; Belyakov, Sergei

    2005-06-28

    Dipeptidyl peptidase IV (DPP IV) is a ubiquitous membrane-bound enzyme that cleaves the two N-terminal amino acids from peptides with a proline or alanine residue in the second position from the amino end. Potential substrates for DPP IV include several neuropeptides, suggesting a role for DPP IV in neurological processes. We have developed a potent DPP IV inhibitor (IC50 = 30 nM), 1-(2-amino-3-methyl-butyryl)-azetidine-2-carbonitrile (AMAC), which has shown efficacy in two established models of psychosis: mescaline-induced scratching and amphetamine-induced hyperactivity. In the mescaline-induced scratching model, AMAC treatment before mescaline administration reduced the number of scratching paroxysms by 68% (P < 0.01). The compound showed a dose-dependent effect, inhibiting significantly at 6, 20 and 60 mg/kg (37%, 39% and 68%, respectively). In the amphetamine-induced hyperactivity model, 50 and 60 mg/kg AMAC, given before injection of amphetamine, significantly reduced hyper-locomotion by 65% and 76%, respectively. Additionally, AMAC showed no significant activity in binding assays for 20 receptors thought to be involved in the pathology of schizophrenia, including dopamine, serotonin and glutamate. A structurally similar analog, 1-(2-dimethylamino-3-methyl-butyryl)-azetidine-2-carbonitrile (DAMAC), that does not inhibit DPP IV, was inactive in both models. Taken together, these data suggest that the antipsychotic effects of AMAC are the result of DPP IV inhibition. PMID:15925329

  3. Specific MAPK inhibitors prevent hyperglycemia-induced renal diseases in type 1 diabetic mouse model.

    PubMed

    Hong, Zhe; Hong, Zongyuan; Wu, Denglong; Nie, Hezhongrong

    2016-08-01

    Mitogen-activated protein kinase (MAPK) and renin-angiotensin system (RAS) play critical roles in the process of renal diseases, but their interaction has not been comprehensively discussed. In the present studies, we investigated the renoprotective effects of MPAK inhibitors on renal diseases in type 1 diabetic mouse model, and clarify the crosstalk among MAPK signaling. Type 1 diabetic mouse model was established in male C57BL/6 J mice, and treated with or without 10 mg/kg MAPK blockers, including ERK inhibitor PD98059, p38 inhibitor SB203850, and JNK inhibitor SP600125 for four weeks. Hyperglycemia induced renal injuries, but treating them with MAPK inhibitors significantly decreased glomerular volume and glycogen in renal tissues. Although slightly changed body weight and fasting blood glucose levels, MAPK inhibitors attenuated blood urea nitrogen, urea protein, and microalbuminuria. Administration also reduced the diabetes-induced RAS activation, including angiotensin II converting enzyme (c) and Ang II, which contributed to its renal protective effects in the diabetic mice. In addition, the anti-RAS of MAPK inhibitor treatment markedly reduced gene expression of tumor necrosis factor-α, interleukin-6, and inducible nitric oxide synthase, fibrotic accumulation, and transforming growth factor-β1 levels in renal tissues. Furthermore, chemical inhibitors and genetic siRNA results identified the crosstalk among the three MAPK signaling, and proved JNK signaling played a critical role in MAPK-mediated ACE pathway in hyperglycemia state. Collectively, these results support the therapeutic effects of MAPK-specific inhibitors, especially JNK inactivation, on hyperglycemia-induced renal damages. PMID:27389030

  4. Sorafenib plus all-trans retinoic acid for AML patients with FLT3-ITD and NPM1 mutations.

    PubMed

    Guenounou, Sarah; Delabesse, Eric; Récher, Christian

    2014-12-01

    Knowledge of the molecular basis of acute myeloid leukaemia has increased considerably in the past few years, and therapies targeting specific molecular defects of this disease are intensively investigated. Patients with both NPM1 and FLT3-ITD mutations encompass 20% of cytogenetically normal AML. The multikinase and FLT3 inhibitor, sorafenib, has shown some efficacy in patients with relapsed FLT3-ITD(+) AML. In addition, it is suggested that all-trans retinoic acid (ATRA) used in combination with chemotherapy has shown to improve outcome of patients harbouring NPM1 mutations. We report here the clinical course of three patients with refractory or relapsed FLT3-ITD(+) /NPM1(+) AML who achieved significant response upon sorafenib and ATRA combination. PMID:24689895

  5. Variability of Voriconazole Trough Levels in Haematological Patients: Influence of Comedications with cytochrome P450(CYP) Inhibitors and/or with CYP Inhibitors plus CYP Inducers.

    PubMed

    Cojutti, Piergiorgio; Candoni, Anna; Forghieri, Fabio; Isola, Miriam; Zannier, Maria Elena; Bigliardi, Sara; Luppi, Mario; Fanin, Renato; Pea, Federico

    2016-06-01

    Voriconazole plasma exposure greatly varies among haematological patients. The purpose of this study was to identify the magnitude of influence of comedications with CYP inhibitors and/or with CYP inhibitors plus CYP inducers on voriconazole trough level (Cmin ). Voriconazole Cmin was retrospectively assessed among haematological patients who underwent therapeutic drug monitoring (TDM). Univariate and multivariate linear mixed-effect regression analyses were performed to identify the independent predictors of normalized Cmin . Of the 83 included patients, 35 had comedications with CYP inhibitors (omeprazole or pantoprazole) and 21 with CYP inhibitors (omeprazole or pantoprazole) plus CYP inducers (methylprednisolone, dexamethasone, phenobarbital, rifampin or carbamazepine). Median Cmin value (n = 199) was 2.4 mg/L with a wide range of distribution (<0.2-13.5 mg/L). Median (IQR) normalized voriconazole Cmin value was significantly higher in the presence of CYP inhibitors (4.20 mg/L, 3.23-5.51 mg/L) than either in the absence of interacting cotreatments (2.55 mg/L, 1.54-3.47 mg/L) or in the presence of CYP inhibitors plus CYP inducers (2.16 mg/L, 1.19-3.09 mg/L). The presence of CYP inhibitors was highly significantly associated with Cmin >5.5 mg/L (OR: 23.22, 95% CI: 3.01-179.09, p = 0.003). No significant association emerged when CYP inhibitors were coadministered with CYP inducers (OR: 3.53, 95% CI: 0.36-34.95, p = 0.280). The amount of expected Cmin increase was significantly influenced by both the type and the dose of the administered proton pump inhibitor. The study highlights that the benefit from TDM of voriconazole may be maximal in those patients who are cotreated with CYP inhibitors and/or with CYP inhibitors plus CYP inducers, especially when receiving proton pump inhibitors (PPIs) at very high dosages intravenously. PMID:26572687

  6. Histone deacetylase inhibitor trichostatin A and proteasome inhibitor PS-341 synergistically induce apoptosis in pancreatic cancer cells

    SciTech Connect

    Bai Jirong . E-mail: jbai@bidmc.harvard.edu; Demirjian, Aram; Sui Jianhua; Marasco, Wayne; Callery, Mark P. . E-mail: mcallery@bidmc.harvard.ede

    2006-10-06

    Pancreatic cancer is a common and lethal malignancy. Pancreatic cancer cells overexpress multiple anti-apoptotic factors and death receptor decoys, and are strongly resistant to radiation and to 5-fluorouracil (5-FU)- or gemcitabine (Gem)-based chemotherapy regimens. We have found that low-dose proteasome inhibitor PS-341 and histone deacetylase inhibitor trichostatin A (TSA) synergistically induce cytotoxicity in a panel of eight diverse pancreatic cancer cell lines. Combining TSA with PS-341 effectively inactivated NF{kappa}B signaling, downregulated the predominant endogenous anti-apoptotic factor Bcl-XL overexpression, and disrupted MAP kinase pathway. The combined drug regimen effectively inflicted an average of 71.5% apoptotic cell death (55.2-80%) in diverse pancreatic cancer cell lines by activating the intrinsic apoptotic pathway. Conclusion: the TSA/PS-341 regimen may represent a potential novel therapeutic strategy for pancreatic cancer.

  7. Genetic and Pharmacological Screens Converge in Identifying FLIP, BCL2, and IAP Proteins as Key Regulators of Sensitivity to the TRAIL-Inducing Anticancer Agent ONC201/TIC10.

    PubMed

    Allen, Joshua E; Prabhu, Varun V; Talekar, Mala; van den Heuvel, A Pieter J; Lim, Bora; Dicker, David T; Fritz, Jennifer L; Beck, Adam; El-Deiry, Wafik S

    2015-04-15

    ONC201/TIC10 is a small-molecule inducer of the TRAIL gene under current investigation as a novel anticancer agent. In this study, we identify critical molecular determinants of ONC201 sensitivity offering potential utility as pharmacodynamic or predictive response markers. By screening a library of kinase siRNAs in combination with a subcytotoxic dose of ONC201, we identified several kinases that ablated tumor cell sensitivity, including the MAPK pathway-inducer KSR1. Unexpectedly, KSR1 silencing did not affect MAPK signaling in the presence or absence of ONC201, but instead reduced expression of the antiapoptotic proteins FLIP, Mcl-1, Bcl-2, cIAP1, cIAP2, and survivin. In parallel to this work, we also conducted a synergy screen in which ONC201 was combined with approved small-molecule anticancer drugs. In multiple cancer cell populations, ONC201 synergized with diverse drug classes, including the multikinase inhibitor sorafenib. Notably, combining ONC201 and sorafenib led to synergistic induction of TRAIL and its receptor DR5 along with a potent induction of cell death. In a mouse xenograft model of hepatocellular carcinoma, we demonstrated that ONC201 and sorafenib cooperatively and safely triggered tumor regressions. Overall, our results established a set of determinants for ONC201 sensitivity that may predict therapeutic response, particularly in settings of sorafenib cotreatment to enhance anticancer responses. PMID:25681273

  8. Efficacy and Safety of Axitinib Versus Sorafenib in Metastatic Renal Cell Carcinoma: Subgroup Analysis of Japanese Patients from the Global Randomized Phase 3 AXIS Trial

    PubMed Central

    Ueda, Takeshi; Uemura, Hirotsugu; Tomita, Yoshihiko; Tsukamoto, Taiji; Kanayama, Hiroomi; Shinohara, Nobuo; Tarazi, Jamal; Chen, Connie; Kim, Sinil; Ozono, Seiichiro; Naito, Seiji; Akaza, Hideyuki

    2013-01-01

    Objective Axitinib is a potent and selective second-generation inhibitor of vascular endothelial growth factor receptors 1, 2 and 3. The efficacy and safety of axitinib in Japanese patients with metastatic renal cell carcinoma were evaluated. Methods A subgroup analysis was conducted in Japanese patients enrolled in the randomized Phase III trial of axitinib versus sorafenib after failure of one prior systemic therapy for metastatic renal cell carcinoma. Results Twenty-five (of 361) and 29 (of 362) patients randomized to the axitinib and sorafenib arms, respectively, were Japanese and included in this analysis. Median progression-free survival in Japanese patients was 12.1 months (95% confidence interval 8.6 to not estimable) for axitinib and 4.9 months (95% confidence interval 2.8–6.6) for sorafenib (hazard ratio 0.390; 95% confidence interval 0.130–1.173; stratified one-sided P = 0.0401). The objective response rate was 52.0% for axitinib and 3.4% for sorafenib (P = 0.0001). The common all-causality adverse events (all grades) in Japanese patients were dysphonia (68%), hypertension (64%), hand–foot syndrome (64%) and diarrhea (56%) for axitinib, and hand–foot syndrome (86%), hypertension (62%) and diarrhea (52%) for sorafenib. The safety profiles of axitinib and sorafenib in Japanese patients were generally similar to those observed in the overall population, with the exceptions of higher incidences of hypertension, dysphonia, hand–foot syndrome, hypothyroidism and stomatitis. Conclusions Axitinib is efficacious and well tolerated in Japanese patients with previously treated metastatic renal cell carcinoma, consistent with the results in the overall population, providing a new targeted therapy for these Japanese patients. PMID:23630366

  9. Hypothermia-induced hyperphosphorylation: a new model to study tau kinase inhibitors

    PubMed Central

    Bretteville, Alexis; Marcouiller, François; Julien, Carl; El Khoury, Noura B.; Petry, Franck R.; Poitras, Isabelle; Mouginot, Didier; Lévesque, Georges; Hébert, Sébastien S.; Planel, Emmanuel

    2012-01-01

    Tau hyperphosphorylation is one hallmark of Alzheimer's disease (AD) pathology. Pharmaceutical companies have thus developed kinase inhibitors aiming to reduce tau hyperphosphorylation. One obstacle in screening for tau kinase inhibitors is the low phosphorylation levels of AD-related phospho-epitopes in normal adult mice and cultured cells. We have shown that hypothermia induces tau hyperphosphorylation in vitro and in vivo. Here, we hypothesized that hypothermia could be used to assess tau kinase inhibitors efficacy. Hypothermia applied to models of biological gradual complexity such as neuronal-like cells, ex vivo brain slices and adult non-transgenic mice leads to tau hyperphosphorylation at multiple AD-related phospho-epitopes. We show that Glycogen Synthase Kinase-3 inhibitors LiCl and AR-A014418, as well as roscovitine, a cyclin-dependent kinase 5 inhibitor, decrease hypothermia-induced tau hyperphosphorylation, leading to different tau phosphorylation profiles. Therefore, we propose hypothermia-induced hyperphosphorylation as a reliable, fast, convenient and inexpensive tool to screen for tau kinase inhibitors. PMID:22761989

  10. Angiotensin-converting enzyme inhibitors-induced angioedema treated by C1 esterase inhibitor concentrate (Berinert®): about one case and review of the therapeutic arsenal

    PubMed Central

    Lipski, Samuel Michael; Casimir, Georges; Vanlommel, Martine; Jeanmaire, Mathieu; Dolhen, Pierre

    2015-01-01

    Key Clinical Message C1 esterase inhibitor (Berinert®) is generally used to treat severe attack of hereditary angioedema. We describe here the case of a patient who presented with a severe angioedema induced by angiotensin-converting enzyme inhibitors (ACEIs) endangering her life. It could be successfully treated with that medicine. PMID:25767713

  11. The class-I HDAC inhibitor MGCD0103 induces apoptosis in Hodgkin lymphoma cell lines and synergizes with proteasome inhibitors by an HDAC6-independent mechanism

    PubMed Central

    Buglio, Daniela; Mamidipudi, Vidya; Khaskhely, Noor M.; Brady, Helen; Heise, Carla; Besterman, Jeffrey; Martell, Robert E.; MacBeth, Kyle; Younes, Anas

    2011-01-01

    Summary Inhibition of histone deacetylase 6 (HDAC6)-dependent aggresome function by pan HDAC inhibitors was recently reported to be a key mechanism underlying the synergistic activity between proteasome inhibitors and HDAC inhibitors in a variety of tumour types. Because these combinations induce significant thrombocytopenia in vivo, we examined whether less toxic, isotype-selective HDAC inhibitors may still synergize with proteasome inhibitors, and if so, by what mechanisms. Here, we showed that the class I HDAC inhibitor, MGCD0103, has a potent antiproliferative activity in Hodgkin lymphoma (HL) cell lines. Furthermore, MGCD0103 induced tumour necrosis factor α (TNF-α) expression and secretion, which was associated with nuclear factor (NF)-κB activation. Selective inhibition of TNF- α expression by short interfering mRNA, or inhibition of MGCD0103-induced NF-kB activation by proteasome inhibitors enhanced MGCD0103-induced cell death. Thus, our results demonstrate that MGCD0103 may synergize with proteasome inhibitors by HDAC6-independent mechanisms, providing mechanistic rationale for exploring this potentially less toxic combination for the treatment of lymphoma. PMID:20880107

  12. Angiotensin-converting enzyme inhibitors-induced angioedema treated by C1 esterase inhibitor concentrate (Berinert®): about one case and review of the therapeutic arsenal.

    PubMed

    Lipski, Samuel Michael; Casimir, Georges; Vanlommel, Martine; Jeanmaire, Mathieu; Dolhen, Pierre

    2015-02-01

    C1 esterase inhibitor (Berinert®) is generally used to treat severe attack of hereditary angioedema. We describe here the case of a patient who presented with a severe angioedema induced by angiotensin-converting enzyme inhibitors (ACEIs) endangering her life. It could be successfully treated with that medicine. PMID:25767713

  13. Cancerous inhibitor of protein phosphatase 2A determines bortezomib-induced apoptosis in leukemia cells

    PubMed Central

    Liu, Chun-Yu; Shiau, Chung-Wai; Kuo, Hsin-Yu; Huang, Hsiang-Po; Chen, Ming-Huang; Tzeng, Cheng-Hwai; Chen, Kuen-Feng

    2013-01-01

    The multiple cellular targets affected by proteasome inhibition implicate a potential role for bortezomib, a first-in-class proteasome inhibitor, in enhancing antitumor activities in hematologic malignancies. Here, we examined the antitumor activity and drug targets of bortezomib in leukemia cells. Human leukemia cell lines were used for in vitro studies. Drug efficacy was evaluated by apoptosis assays and associated molecular events assessed by Western Blot. Gene silencing was performed by small interference RNA. Drug was tested in vivo in xenograft models of human leukemia cell lines and in primary leukemia cells. Clinical samples were assessed by immunohistochemical staining. Bortezomib differentially induced apoptosis in leukemia cells that was independent of its proteasome inhibition. Cancerous inhibitor of protein phosphatase 2A, a cellular inhibitor of protein phosphatase 2A, mediated the apoptotic effect of bortezomib. Bortezomib increased protein phosphatase 2A activity in sensitive leukemia cells (HL-60 and KG-1), but not in resistant cells (MOLT-3 and K562). Bortezomib’s downregulation of cancerous inhibitor of protein phosphatase 2A and phospho-Akt correlated with its drug sensitivity. Furthermore, cancerous inhibitor of protein phosphatase 2A negatively regulated protein phosphatase 2A activity. Ectopic expression of CIP2A up-regulated phospho-Akt and protected HL-60 cells from bortezomib-induced apoptosis, whereas silencing CIP2A overcame the resistance to bortezomib-induced apoptosis in MOLT3 and K562 cells. Importantly, bortezomib exerted in vivo antitumor activity in HL-60 xenografted tumors and induced cell death in some primary leukemic cells. Cancerous inhibitor of protein phosphatase 2A was expressed in leukemic blasts from bone marrow samples. Cancerous inhibitor of protein phosphatase 2A plays a major role in mediating bortezomib-induced apoptosis in leukemia cells. PMID:22983581

  14. Population pharmacokinetic analysis of sorafenib in patients with solid tumours

    PubMed Central

    Jain, Lokesh; Woo, Sukyung; Gardner, Erin R; Dahut, William L; Kohn, Elise C; Kummar, Shivaani; Mould, Diane R; Giaccone, Giuseppe; Yarchoan, Robert; Venitz, Jürgen; Figg, William D

    2011-01-01

    AIMS To characterize the pharmacokinetics (PK) of sorafenib in patients with solid tumours and to evaluate the possible effects of demographic, clinical and pharmacogenetic (CYP3A4*1B, CYP3A5*3C, UGT1A9*3 and UGT1A9*5) covariates on the disposition of sorafenib. METHODS PK were assessed in 111 patients enrolled in five phase I and II clinical trials, where sorafenib 200 or 400 mg was administered twice daily as a single agent or in combination therapy. All patients were genotyped for polymorphisms in metabolic enzymes for sorafenib. Population PK analysis was performed by using nonlinear mixed effects modelling (NONMEM). The final model was validated using visual predictive checks and nonparametric bootstrap analysis. RESULTS A one compartment model with four transit absorption compartments and enterohepatic circulation (EHC) adequately described sorafenib disposition. Baseline bodyweight was a statistically significant covariate for distributional volume, accounting for 4% of inter-individual variability (IIV). PK model parameter estimates (range) for an 80 kg patient were clearance 8.13 l h−1 (3.6–22.3 l h−1), volume 213 l (50–1000 l), mean absorption transit time 1.98 h (0.5–13 h), fraction undergoing EHC 50% and average time to gall bladder emptying 6.13 h. CONCLUSIONS Overall, population PK analysis was consistent with known biopharmaceutical/PK characteristics of oral sorafenib. No clinically important PK covariates were identified. PMID:21392074

  15. The lack of target specificity of small molecule anticancer kinase inhibitors is correlated with their ability to damage myocytes in vitro

    SciTech Connect

    Hasinoff, Brian B. Patel, Daywin

    2010-12-01

    Many new targeted small molecule anticancer kinase inhibitors are actively being developed. However, the clinical use of some kinase inhibitors has been shown to result in cardiotoxicity. In most cases the mechanisms by which they exert their cardiotoxicity are not well understood. We have used large scale profiling data on 8 FDA-approved tyrosine kinase inhibitors and 10 other kinase inhibitors to a panel of 317 kinases in order to correlate binding constants and kinase inhibitor binding selectivity scores with kinase inhibitor-induced damage to neonatal rat cardiac myocytes. The 18 kinase inhibitors that were the subject of this study were: canertinib, dasatinib, dovitinib, erlotinib, flavopiridol, gefitinib, imatinib, lapatinib, midostaurin, motesanib, pazopanib, sorafenib, staurosporine, sunitinib, tandutinib, tozasertib, vandetanib and vatalanib. The combined tyrosine kinase and serine-threonine kinase selectivity scores were highly correlated with the myocyte-damaging effects of the kinase inhibitors. This result suggests that myocyte damage was due to a lack of target selectivity to binding of both tyrosine kinases and serine-threonine kinases, and was not due to binding to either group specifically. Finally, the strength of kinase inhibitor binding for 290 kinases was examined for correlations with myocyte damage. Kinase inhibitor binding was significantly correlated with myocyte damage for 12 kinases. Thus, myocyte damage may be multifactorial in nature with the inhibition of a number of kinases involved in producing kinase inhibitor-induced myocyte damage.

  16. The lack of target specificity of small molecule anticancer kinase inhibitors is correlated with their ability to damage myocytes in vitro.

    PubMed

    Hasinoff, Brian B; Patel, Daywin

    2010-12-01

    Many new targeted small molecule anticancer kinase inhibitors are actively being developed. However, the clinical use of some kinase inhibitors has been shown to result in cardiotoxicity. In most cases the mechanisms by which they exert their cardiotoxicity are not well understood. We have used large scale profiling data on 8 FDA-approved tyrosine kinase inhibitors and 10 other kinase inhibitors to a panel of 317 kinases in order to correlate binding constants and kinase inhibitor binding selectivity scores with kinase inhibitor-induced damage to neonatal rat cardiac myocytes. The 18 kinase inhibitors that were the subject of this study were: canertinib, dasatinib, dovitinib, erlotinib, flavopiridol, gefitinib, imatinib, lapatinib, midostaurin, motesanib, pazopanib, sorafenib, staurosporine, sunitinib, tandutinib, tozasertib, vandetanib and vatalanib. The combined tyrosine kinase and serine-threonine kinase selectivity scores were highly correlated with the myocyte-damaging effects of the kinase inhibitors. This result suggests that myocyte damage was due to a lack of target selectivity to binding of both tyrosine kinases and serine-threonine kinases, and was not due to binding to either group specifically. Finally, the strength of kinase inhibitor binding for 290 kinases was examined for correlations with myocyte damage. Kinase inhibitor binding was significantly correlated with myocyte damage for 12 kinases. Thus, myocyte damage may be multifactorial in nature with the inhibition of a number of kinases involved in producing kinase inhibitor-induced myocyte damage. PMID:20832415

  17. MEK1/2 inhibitors induce interleukin-5 expression in mouse macrophages and lymphocytes.

    PubMed

    Li, Xiaoju; Cao, Xingyue; Zhang, Xiaomeng; Kang, Yanhua; Zhang, Wenwen; Yu, Miao; Ma, Chuanrui; Han, Jihong; Duan, Yajun; Chen, Yuanli

    2016-05-13

    Uptake of oxidized low-density lipoprotein (oxLDL) by macrophages facilitates the formation of foam cells, the prominent part of atherosclerotic lesions. Interleukin-5 (IL-5) is a cytokine regulating interactions between immune cells. It also activates the production of T15/EO6 IgM antibodies in B-1 cells, which can bind oxLDL thereby demonstrating anti-atherogenic properties. We previously reported that inhibition of extracellular signal-regulated kinases 1 and 2 (ERK1/2) by mitogen-activated protein kinase kinases 1/2 (MEK1/2) inhibitors can reduce atherosclerosis. In this study, we determined the effects of MEK1/2 inhibitors on IL-5 production both in vitro and in vivo. In vitro, MEK1/2 inhibitors (PD98059 and U0126) substantially inhibited phosphorylation of MEK1/2 and ERK1/2. Associated with inhibition of ERK1/2 phosphorylation both in vitro and in vivo, MEK1/2 inhibitors induced IL-5 protein expression in macrophages (RAW macrophages and peritoneal macrophages) and lymphocytes (EL-4 cells). In vivo, administration of mice with MEK1/2 inhibitors increased serum IL-5 levels, and IL-5 protein expression in mouse spleen and liver. At the mechanistic level, we determined that MEK1/2 inhibitors activated IL-5 mRNA expression and IL-5 promoter activity in the liver X receptor (LXR) dependent manner indicating the induction of IL-5 transcription. In addition, we determined that MEK1/2 inhibitors enhanced IL-5 protein stability. Taken together, our study demonstrates that MEK1/2 inhibitors induce IL-5 production which suggests another anti-atherogenic mechanism of MEK1/2 inhibitors. PMID:27045084

  18. Proteasome inhibitors attenuated cholesterol-induced cardiac hypertrophy in H9c2 cells.

    PubMed

    Lee, Hyunjung; Park, Jinyoung; Kim, Eunice EunKyeong; Yoo, Young Sook; Song, Eun Joo

    2016-05-01

    The Ubiquitin proteasome system (UPS) plays roles in protein degradation, cell cycle control, and growth and inflammatory cell signaling. Dysfunction of UPS in cardiac diseases has been seen in many studies. Cholesterol acts as an inducer of cardiac hypertrophy. In this study, the effect of proteasome inhibitors on the cholesterol-induced hypertrophic growth in H9c2 cells is examined in order to observe whether UPS is involved in cardiac hypertrophy. The treatment of proteasome inhibitors MG132 and Bortezomib markedly reduced cellular surface area and mRNA expression of β-MHC in cholesterol-induced cardiac hypertrophy. In addition, activated AKT and ERK were significantly attenuated by MG132 and Bortezomib in cholesterol- induced cardiac hypertrophy. We demonstrated that cholesterol- induced cardiac hypertrophy was suppressed by proteasome inhibitors. Thus, regulatory mechanism of cholesterol- induced cardiac hypertrophy by proteasome inhibitors may provide a new therapeutic strategy to prevent the progression of heart failure. [BMB Reports 2016; 49(5): 270-275]. PMID:26592933

  19. Lipopolysaccharide-Related Stimuli Induce Expression of the Secretory Leukocyte Protease Inhibitor, a Macrophage-Derived Lipopolysaccharide Inhibitor

    PubMed Central

    Jin, Fenyu; Nathan, Carl F.; Radzioch, Danuta; Ding, Aihao

    1998-01-01

    Mouse secretory leukocyte protease inhibitor (SLPI) was recently characterized as a lipopolysaccharide (LPS)-induced product of macrophages that antagonizes their LPS-induced activation of NF-κB and production of NO and tumor necrosis factor (TNF) (F. Y. Jin, C. Nathan, D. Radzioch, and A. Ding, Cell 88:417–426, 1997). To better understand the role of SLPI in innate immune and inflammatory responses, we examined the kinetics of SLPI expression in response to LPS, LPS-induced cytokines, and LPS-mimetic compounds. SLPI mRNA was detectable in macrophages by Northern blot analysis within 30 min of exposure to LPS but levels peaked only at 24 to 36 h and remained elevated at 72 h. Despite the slowly mounting and prolonged response, early expression of SLPI mRNA was cycloheximide resistant. Two LPS-induced proteins—interleukin-10 (IL-10) and IL-6—also induced SLPI, while TNF and IL-1β did not. The slow attainment of maximal induction of SLPI by LPS in vitro was mimicked by infection with Pseudomonas aeruginosa in vivo, where SLPI expression in the lung peaked at 3 days. Two LPS-mimetic molecules—taxol from yew bark and lipoteichoic acid (LTA) from gram-positive bacterial cell walls—also induced SLPI. Transfection of macrophages with SLPI inhibited their LTA-induced NO production. An anti-inflammatory role for macrophage-derived SLPI seems likely based on SLPI’s slowly mounting production in response to constituents of gram-negative and gram-positive bacteria, its induction both as a direct response to LPS and as a response to anti-inflammatory cytokines induced by LPS, and its ability to suppress the production of proinflammatory products by macrophages stimulated with constituents of both gram-positive and gram-negative bacteria. PMID:9596701

  20. Salicylates inhibit PAF-acether-induced rat paw oedema when cyclooxygenase inhibitors are ineffective.

    PubMed

    Cordeiro, R S; Silva, P M; Martins, M A; Vargaftig, B B

    1986-11-01

    The cyclooxygenase inhibitors indomethacin, piroxicam, ibuprofen, naproxen and flurbiprofen failed to block rat paw oedema induced by PAF-acether, whereas aspirin and sodium salicylate were effective. Two mixed cyclooxygenase and lipoxygenase inhibitors NDGA, BW 755C and dexamethasone reduced oedema in a dose - dependently. The selective PAF-acether antagonist, BN 52021, was effective against PAF-acether at 5 - 20 mg/kg. The lipoxygenase derivates may be involved in paw oedema induced by PAF-acether in the rat and the inhibition produced by aspirin and by sodium salicylate should involve mechanisms other than the cyclooxygenase pathway. PMID:3103172

  1. Icatibant in the Treatment of Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema

    PubMed Central

    Crooks, Neil H.; Patel, Jaimin; Diwakar, Lavanya; Smith, Fang Gao

    2014-01-01

    We describe the case of a 75-year-old woman who presented with massive tongue and lip swelling secondary to angiotensin-converting enzyme inhibitor-induced angioedema. An awake fibre-optic intubation was performed because of impending airway obstruction. As there was no improvement in symptoms after 72 hours, the selective bradykinin B2 receptor antagonist icatibant (Firazyr) was administered and the patient's trachea was successfully extubated 36 hours later. To our knowledge this is the first documented case of icatibant being used for the treatment of angiotensin-converting enzyme inhibitor-induced angioedema in the United Kingdom and represents a novel therapeutic option in its management. PMID:25328718

  2. Microtubule inhibitors block the morphological changes induced in Drosophila blood cells by a parasitoid wasp factor.

    PubMed

    Rizki, R M; Rizki, T M

    1990-03-15

    The shape change of Drosophila melanogaster blood cells (lamellocytes) from discoidal to bipolar that is caused by a factor from the female parasitoid Leptopilina heterotoma is blocked by the tubulin inhibitors vinblastine and vincristine in vitro. The actin inhibitor, cytochalasin B, causes arborization of Drosophila lamellocytes and acts synergistically with the wasp factor to alter lamellocyte morphology. Lamellocyte aborization induced by cytochalasin B is blocked by simultaneous treatment with vinblastine. These observations indicate that the changes in lamellocyte shape induced by both the wasp factor and cytochalasin B require microtubule assembly. PMID:2311722

  3. Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization.

    PubMed

    Meng, Zhen; Gan, Ye-Hua

    2015-05-01

    Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation. PMID:25770423

  4. Inhibitors that stabilize a closed RAF kinase domain conformation induce dimerization

    PubMed Central

    Lavoie, Hugo; Thevakumaran, Neroshan; Gavory, Gwenaëlle; Li, John; Padeganeh, Abbas; Guiral, Sébastien; Duchaine, Jean; Mao, Daniel Y. L.; Bouvier, Michel; Sicheri, Frank; Therrien, Marc

    2016-01-01

    RAF kinases play a prominent role in cancer. Their mode of activation is complex, but critically requires dimerization of their kinase domains. Unexpectedly, several ATP-competitive RAF inhibitors were recently found to promote dimerization and transactivation of RAF kinases in a RAS-dependent manner and as a result undesirably stimulate RAS/ERK-mediated cell growth. The mechanism by which these inhibitors induce RAF kinase domain dimerization remains unclear. Here we describe BRET-based biosensors for the extended RAF family enabling the detection of RAF dimerization in living cells. Notably, we demonstrate the utility of these tools for profiling kinase inhibitors that selectively modulate RAF dimerization as well as for probing structural determinants of RAF dimerization in vivo. Our findings, which appear generalizable to other kinase families allosterically regulated by kinase domain dimerization, suggest a model whereby ATP-competitive inhibitors mediate RAF dimerization by stabilizing a rigid closed conformation of the kinase domain. PMID:23685672

  5. Activation of mPTP-dependent mitochondrial apoptosis pathway by a novel pan HDAC inhibitor resminostat in hepatocellular carcinoma cells.

    PubMed

    Fu, Meili; Shi, Wenhong; Li, Zhengling; Liu, Haiyan

    2016-09-01

    Over-expression and aberrant activation of histone deacetylases (HDACs) are often associated with poor prognosis of hepatocellular carcinoma (HCC). Here, we evaluated the potential anti-hepatocellular carcinoma (HCC) cell activity by resminostat, a novel pan HDAC inhibitor (HDACi). We demonstrated that resminostat induced potent cytotoxic and anti-proliferative activity against established HCC cell lines (HepG2, HepB3, SMMC-7721) and patient-derived primary HCC cells. Further, resminostat treatment in HCC cells activated mitochondrial permeability transition pore (mPTP)-dependent apoptosis pathway, which was evidenced by physical association of cyclophilin-D and adenine nucleotide translocator 1 (ANT-1), mitochondrial depolarization, cytochrome C release and caspase-9 activation. Intriguingly, the mPTP blockers (sanglifehrin A and cyclosporine A), shRNA knockdown of cyclophilin-D or the caspase-9 inhibitor dramatically attenuated resminostat-induced HCC cell apoptosis and cytotoxicity. Reversely, HCC cells with exogenous cyclophilin-D over-expression were hyper-sensitive to resminostat. Intriguingly, a low concentration of resminostat remarkably potentiated sorafenib-induced mitochondrial apoptosis pathway activation, leading to a profound cytotoxicity in HCC cells. The results of this preclinical study indicate that resminostat (or plus sorafenib) could be further investigated as a valuable anti-HCC strategy. PMID:27144317

  6. Shikonin, dually functions as a proteasome inhibitor and a necroptosis inducer in multiple myeloma cells.

    PubMed

    Wada, Naoko; Kawano, Yawara; Fujiwara, Shiho; Kikukawa, Yoshitaka; Okuno, Yutaka; Tasaki, Masayoshi; Ueda, Mitsuharu; Ando, Yukio; Yoshinaga, Kazuya; Ri, Masaki; Iida, Shinsuke; Nakashima, Takayuki; Shiotsu, Yukimasa; Mitsuya, Hiroaki; Hata, Hiroyuki

    2015-03-01

    Shikonin (SHK), a natural small agent (MW 288.3), reportedly induces cell death in various tumor cells. We have found that SHK also exerts potent cytocidal effects on human multiple myeloma (MM) cells, but its anticancer mechanism in MM cells remains to be elucidated. SHK at 2.5-5 µM induced apoptosis in seven MM cell lines, including the bortezomib-resistant cell line KMS11/BTZ. The IC50 value of SHK against KMS11/BTZ was comparable to that of a parental cell line KMS11 (1.1 and 1.56 µM, respectively). SHK induces accumulation of ubiquitinated proteins and activates XBP-1 in MM cells, suggesting that SHK functions as a proteasome inhibitor, eventually inducing ER stress-associated apoptosis. SHK increases levels of HSP70/72, which protects cells from apoptosis, and exerts greater cytocidal effects in combination with the HSP70/72 inhibitor VER-155008. At higher concentrations (10-20 µM), SHK induced cell death, which was completely inhibited by a necroptosis inhibitor, necrostatin-1 (Nec-1), while the cytocidal activity was unaffected by Z-VAD-FMK, strongly suggesting that cell death is induced by SHK at high concentrations through necroptosis. The present data show for the first time that SHK induces cell death in MM cells. SHK efficiently induces apoptosis and combination of heat shock protein inhibitor with low dose SHK enhances apoptosis, while high dose SHK induces necroptosis in MM cells. These findings together support the use of SHK as a potential therapeutic agent for MM. PMID:25530098

  7. COX-2 inhibitors block chemotherapeutic agent-induced apoptosis prior to commitment in hematopoietic cancer cells.

    PubMed

    Cerella, Claudia; Sobolewski, Cyril; Chateauvieux, Sébastien; Henry, Estelle; Schnekenburger, Michael; Ghelfi, Jenny; Dicato, Mario; Diederich, Marc

    2011-11-15

    Enzymatic inhibitors of pro-inflammatory cyclooxygenase-2 (COX-2) possess multiple anti-cancer effects, including chemosensitization. These effects are not always linked to the inhibition of the COX-2 enzyme. Here we analyze the effects of three COX-2 enzyme inhibitors (nimesulide, NS-398 and celecoxib) on apoptosis in different hematopoietic cancer models. Surprisingly, COX-2 inhibitors strongly prevent apoptosis induced by a panel of chemotherapeutic agents. We selected U937 cells as a model of sensitive cells for further studies. Here, we provide evidence that the protective effect is COX-independent. No suppression of the low basal prostaglandin (PG)E(2) production may be observed upon treatment by COX-2 inhibitors. Besides, the non-active celecoxib analog 2,5-dimethyl-celecoxib is able to protect from apoptosis as well. We demonstrate early prevention of the stress-induced apoptotic signaling, prior to Bax/Bak activation. This preventive effect fits with an impairment of the ability of chemotherapeutic agents to trigger apoptogenic stress. Accordingly, etoposide-induced DNA damage is strongly attenuated in the presence of COX-2 inhibitors. In contrast, COX-2 inhibitors do not exert any anti-apoptotic activity when cells are challenged with physiological stimuli (anti-Fas, TNFα or Trail) or with hydrogen peroxide, which do not require internalization and/or are not targeted by chemoresistance proteins. Altogether, our findings show a differential off-target anti-apoptotic effect of COX-2 inhibitors on intrinsic vs. extrinsic apoptosis at the very early steps of intracellular signaling, prior to commitment. The results imply that an exacerbation of the chemoresistance phenomena may be implicated. PMID:21745461

  8. Attenuation by phosphodiesterase inhibitors of lipopolysaccharide-induced thromboxane release and bronchoconstriction in rat lungs.

    PubMed

    Uhlig, S; Featherstone, R L; Held, H D; Nüsing, R; Schudt, C; Wendel, A

    1997-12-01

    Exposure of perfused rat lungs to lipopolysaccharides (LPS) causes induction of cyclooxygenase-2 followed by thromboxane (TX)-mediated bronchoconstriction (BC). Recently, phosphodiesterase (PDE) inhibitors have received much interest because they not only are bronchodilators but also can suppress release of proinflammatory mediators. In the present study, we investigated the effect of three different PDE inhibitors on TX release and BC in LPS-exposed perfused rat lungs. The PDE inhibitors used were motapizone (PDE III specific), rolipram (PDE IV specific), and zardaverine (mixed PDE III and IV specific). At 5 microM, a concentration at which all three compounds selectively block their respective PDE isoenzyme, rolipram (IC50 = 0.04 microM) and zardaverine (IC50 = 1.8 microM) largely attenuated the LPS-induced BC, whereas motapizone was almost ineffective (IC50 = 40 microM). In contrast to LPS, BC induced by the TX-mimetic U46619 was prevented with comparable strength by motapizone and rolipram. In LPS-treated lungs, the TX release was reduced to 50% of controls by rolipram and zardaverine but was unaltered in the presence of 5 microM motapizone. Increasing intracellular cAMP through perfusion of db-cAMP or forskolin (activates adenylate cyclase) also reduced TX release and BC. We conclude that PDE inhibitors act via elevation of intracellular cAMP. Although both PDE III and PDE IV inhibitors can relax airway smooth muscle, in the model of LPS-induced BC, PDE IV inhibitors are more effective because (in contrast to PDE III inhibitors) they also attenuate TX release. PMID:9400021

  9. A phase II study of TRC105 in patients with hepatocellular carcinoma who have progressed on sorafenib

    PubMed Central

    Duffy, AG; Ulahannan, SV; Cao, L; Rahma, OE; Makarova-Rusher, OV; Kleiner, DE; Fioravanti, S; Walker, M; Carey, S; Yu, Y; Venkatesan, AM; Turkbey, B; Choyke, P; Trepel, J; Bollen, KC; Steinberg, SM; Figg, WD

    2015-01-01

    Background Endoglin is an endothelial cell membrane receptor essential for angiogenesis and highly expressed on the vasculature of many tumor types, including hepatocellular carcinoma (HCC). TRC105 is a chimeric IgG1 anti-CD105 monoclonal antibody that inhibits angiogenesis and tumor growth by endothelial cell growth inhibition, ADCC and apoptosis, and complements VEGF inhibitors. Objective The aim of this phase II study was to evaluate the efficacy of anti-endoglin therapy with TRC105 in patients with advanced HCC, post-sorafenib. Methods Patients with HCC and compensated liver function (Childs-Pugh A/B7), ECOG 0/1, were enrolled to a single-arm, phase II study of TRC105 15 mg/kg IV every two weeks. Patients must have progressed on or been intolerant of prior sorafenib. A Simon optimal two-stage design was employed with a 50% four-month PFS target for progression to the second stage. Correlative biomarkers evaluated included DCE-MRI as well as plasma levels of angiogenic biomarkers and soluble CD105. Results A total accrual of 27 patients was planned. However, because of lack of efficacy and in accordance with the Simon two-stage design, 11 patients were enrolled. There were no grade 3/4 treatment-related toxicities. Most frequent toxicities were headache (G2; N = 3) and epistaxis (G1; N = 4). One patient had a confirmed partial response by standard RECIST criteria and biologic response on DCE-MRI but the four-month PFS was insufficient to proceed to the second stage of the study. Conclusions: TRC105 was well tolerated in this HCC population following sorafenib. Although there was evidence of clinical activity, this did not meet prespecified criteria to proceed to the second stage. TRC105 development in HCC continues as combination therapy with sorafenib. PMID:26535124

  10. Quinazolines as Apoptosis Inducers and Inhibitors: A Review of Patent Literature.

    PubMed

    Mehndiratta, Samir; Sapra, Sameer; Singh, Gurpreet; Singh, Manwinder; Nepali, Kunal

    2016-01-01

    Quinazoline scaffold has been successfully utilized for development of various inhibitors of tubulin, epidermal growth factor receptor (EGFR), polo like kinases (PLKs), Hedgehog-Gli signaling pathway and protein kinase B (PKB) /Akt pathway. Compounds based on quinazolines have shown efficacies in µM to nM range in various cancer cell lines and thus could be useful scaffolds for development of both apoptosis inducers as well as inhibitors. This compilation is based on various patents published till 2015 and divides the quinazolines in two main categories: Quinazolines as apoptosis inducers and as apoptosis inhibitors. These two main categories are further sub-categorized based on the use/pharmacological indications for these classes of patented compounds. This review will act as a tool for the researchers working on exploring the anticancer potential of quinazoline as a privileged heterocyclic. The promising anticancer profile of some of the quinazoline based compounds clearly highlights the clinical potential of this heterocycle. PMID:26681186

  11. A combination of sorafenib and nilotinib reduces the growth of castrate-resistant prostate cancer

    PubMed Central

    Archibald, Monica; Pritchard, Tara; Nehoff, Hayley; Rosengren, Rhonda J; Greish, Khaled; Taurin, Sebastien

    2016-01-01

    Castrate-resistant prostate cancer (CRPC) remains incurable due to the lack of effective therapies. Several tyrosine kinases have been implicated in the development and growth of CRPC, as such targeting these kinases may offer an alternative therapeutic strategy. We established the combination of two tyrosine kinase inhibitors (TKIs), sorafenib and nilotinib, as the most cytotoxic. In addtion, to improve their bioavailability and reduce their metabolism, we encapsulated sorafenib and nilotinib into styrene-co-maleic acid micelles. The micelles’ charge, size, and release rate were characterized. We assessed the effect of the combination on the cytotoxicity, cell cycle, apoptosis, protein expression, tumor spheroid integrity, migration, and invasion. The micelles exhibited a mean diameter of 100 nm, a neutral charge, and appeared highly stable. The micellar TKIs promoted greater cytotoxicity, decreased cell proliferation, and increased apoptosis relative to the free TKIs. In addition, the combination reduced the expression and activity of several tyrosine kinases and reduced tumor spheroid integrity and metastatic potential of CRPC cell lines more efficiently than the single treatments. The combination increased the therapeutic potential and demonstrated the relevance of a targeted combination therapy for the treatment of CRPC. In addition, the efficacy of the encapsulated drugs provides the basis for an in vivo preclinical testing. PMID:26811677

  12. A combination of sorafenib and nilotinib reduces the growth of castrate-resistant prostate cancer.

    PubMed

    Archibald, Monica; Pritchard, Tara; Nehoff, Hayley; Rosengren, Rhonda J; Greish, Khaled; Taurin, Sebastien

    2016-01-01

    Castrate-resistant prostate cancer (CRPC) remains incurable due to the lack of effective therapies. Several tyrosine kinases have been implicated in the development and growth of CRPC, as such targeting these kinases may offer an alternative therapeutic strategy. We established the combination of two tyrosine kinase inhibitors (TKIs), sorafenib and nilotinib, as the most cytotoxic. In addtion, to improve their bioavailability and reduce their metabolism, we encapsulated sorafenib and nilotinib into styrene-co-maleic acid micelles. The micelles' charge, size, and release rate were characterized. We assessed the effect of the combination on the cytotoxicity, cell cycle, apoptosis, protein expression, tumor spheroid integrity, migration, and invasion. The micelles exhibited a mean diameter of 100 nm, a neutral charge, and appeared highly stable. The micellar TKIs promoted greater cytotoxicity, decreased cell proliferation, and increased apoptosis relative to the free TKIs. In addition, the combination reduced the expression and activity of several tyrosine kinases and reduced tumor spheroid integrity and metastatic potential of CRPC cell lines more efficiently than the single treatments. The combination increased the therapeutic potential and demonstrated the relevance of a targeted combination therapy for the treatment of CRPC. In addition, the efficacy of the encapsulated drugs provides the basis for an in vivo preclinical testing. PMID:26811677

  13. Insect and wound induced GUS gene expression from a Beta vulgaris proteinase inhibitor gene promoter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inducible gene promoters that are specifically activated by pathogen invasion or insect pest attack are needed for effective expression of resistance genes to control plant diseases. In the present study, a promoter from a serine proteinase inhibitor gene (BvSTI) shown to be up-regulated in resist...

  14. MAP KINASE ERK 1/2 INHIBITORS INDUCE DYSMORPHOLOGY IN MOUSE WHOLE EMBRYO CULTURE

    EPA Science Inventory

    ROSEN, M.B. and E. S. HUNTER. Reproductive Toxicology Division, NHEERL, ORD, U.S. EPA, Research Triangle Park, North Carolina. MAP kinase Erk1/2 inhibitors induce dysmorphology in mouse whole embryo culture.

    MAP Kinase signal transduction is associated with a variety ...

  15. Proteasome inhibitors induce apoptosis and reduce viral replication in primary effusion lymphoma cells

    SciTech Connect

    Saji, Chiaki; Higashi, Chizuka; Niinaka, Yasufumi; Yamada, Koji; Noguchi, Kohji; Fujimuro, Masahiro

    2011-12-02

    Highlights: Black-Right-Pointing-Pointer Constitutive NF-{kappa}B signaling is essential for the survival and growth of PEL cells. Black-Right-Pointing-Pointer NF-{kappa}B signaling is upregulated by the proteasome-dependent degradation of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress NF-{kappa}B signaling and induce apoptosis in PEL cells through stabilization of I{kappa}B{alpha}. Black-Right-Pointing-Pointer Proteasome inhibitors suppress viral replication in PEL cells during lytic KSHV infection. -- Abstract: Primary effusion lymphoma (PEL) is an aggressive neoplasm caused by Kaposi's sarcoma-associated herpesvirus (KSHV). This study provides evidence that proteasomal activity is required for both survival of PEL cells stably harboring the KSHV genome and viral replication of KSHV. We evaluated the cytotoxic effects of proteasome inhibitors on PEL cells. The proteasome inhibitors MG132, lactacystin, and proteasome inhibitor I dramatically inhibited cell proliferation and induced apoptosis of PEL cells through the accumulation of p21 and p27. Furthermore, proteasome inhibitors induced the stabilization of NF-{kappa}B inhibitory molecule (I{kappa}B{alpha}) and suppressed the transcriptional activity of NF-{kappa}B in PEL cells. The NF-{kappa}B specific inhibitor BAY11-7082 also induced apoptosis in PEL cells. The constitutive activation of NF-{kappa}B signaling is essential for the survival and growth of B cell lymphoma cells, including PEL cells. NF-{kappa}B signaling is upregulated by proteasome-dependent degradation of I{kappa}B{alpha}. The suppression of NF-{kappa}B signaling by proteasome inhibitors may contribute to the induction of apoptosis in PEL cells. In addition, proteasome activity is required for KSHV replication in KSHV latently infected PEL cells. MG132 reduced the production of progeny virus from PEL cells at low concentrations, which do not affect PEL cell growth. These findings suggest that proteasome inhibitors

  16. Ciprofloxacin-Induced Antibacterial Activity Is Attenuated by Phosphodiesterase Inhibitors

    PubMed Central

    Masadeh, Majed M.; Alzoubi, Karem H.; Khabour, Omar F.; Al-Azzam, Sayer I.

    2014-01-01

    Background Ciprofloxacin is a commonly used antibiotic for urinary tract infection that interacts with bacterial topoisomerases leading to oxidative radicals generation and bacterial cell death. Phosphodiesterase inhibitors (PDEis), on the other hand, are commonly used drugs for the management of erectile dysfunction. The group includes agents such as sildenafil, vardenafil, and tadalafil. Objectives We investigated whether PDEi could interfere with the antibacterial activity of ciprofloxacin. Methods PDEis were tested in several reference bacteria, including Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Staphylococcus epidermidis, Acinetobacter baumannii, Proteus mirabilis, and Klebsiella pneumoniae utilizing a standard disc diffusion method and measuring both zones of inhibition and MIC. Results Results from both assays indicated that ciprofloxacin demonstrates potent activity against the tested reference bacteria. Additionally, when bacteria were treated with a combination of ciprofloxacin and sildenafil, tadalafil, or vardenafil, the zones of the combination inhibition were significantly reduced, whereas the MIC values were significantly greater than those of ciprofloxacin alone for all tested bacterial strains. In an attempt to examine the mechanism by which PDEis interfere with the action of ciprofloxacin, we utilized the in vitro E coli DNA gyrase cleavage assay. The results showed that PDEi drugs had no effect on ciprofloxacin’s inhibition of E coli gyrase activity. Conclusions Pretreatment of various reference bacterial cells with PDEis largely inhibited the antibacterial activity of ciprofloxacin. PMID:26649077

  17. A Phase I Study of High-Dose Interleukin-2 With Sorafenib in Patients With Metastatic Renal Cell Carcinoma and Melanoma

    PubMed Central

    Lam, Elaine; Mortazavi, Amir; Kendra, Kari; Lesinski, Gregory B.; Mace, Thomas A.; Geyer, Susan; Carson, William E.; Tahiri, Sanaa; Bhinder, Arvinder; Clinton, Steven K.; Olencki, Thomas

    2014-01-01

    This study was designed to evaluate the safety and feasibility of high-dose interleukin-2 (HD IL-2) followed by sorafenib in patients with metastatic melanoma (MM) and renal cell carcinoma (RCC). Biomarkers relevant to the antitumor effects of IL-2 that may be altered by sorafenib including the percentages of natural T-regulatory cells (Tregs), myeloid-derived suppressor cells (MDSC), and STAT5 phosphorylation (pSTAT5) in T cells were evaluated. We hypothesized that the proposed treatment schedule is feasible and safe and may lead to enhanced tumor response. A phase I dose escalation trial was conducted in patients with either metastatic RCC or MM. HD IL-2 (600,000 IU/kg IV q8h×8–12 doses) was administered on days 1–5 and 15–19, followed by sorafenib on days 29–82. The sorafenib dose was escalated. The percentage of Tregs, MDSC, and pSTAT5 in T cells were evaluated in peripheral blood by flow cytometry. Twelve of the 18 patients were evaluable for dose-limiting toxicity. No dose-limiting toxicity was observed. The treatment-related toxicity was predictable and did not seem to be additive with this schedule of administration. Partial responses were seen in 3 patients. No significant changes in the percentage of circulating Treg and MDSC were observed, whereas sorafenib did not adversely affect the ability of IL-2 to induce pSTAT5 in T cells. HD IL-2 followed by sorafenib was safe and feasible in patients with MM and RCC and did not adversely affect T-cell signaling through STAT5 in response to IL-2. PMID:24598448

  18. Sorafenib in advanced, heavily pretreated patients with soft tissue sarcomas.

    PubMed

    Brämswig, Kira; Ploner, Ferdinand; Martel, Alexandra; Bauernhofer, Thomas; Hilbe, Wolfgang; Kühr, Thomas; Leitgeb, Clemens; Mlineritsch, Brigitte; Petzer, Andreas; Seebacher, Veronika; Stöger, Herbert; Girschikofsky, Michael; Hochreiner, Gerhard; Ressler, Sigrun; Romeder, Franz; Wöll, Ewald; Brodowicz, Thomas

    2014-08-01

    Therapeutic options for patients with advanced pretreated soft tissue sarcomas are limited. However, in this setting, sorafenib has shown promising results. We reviewed the data of 33 patients with soft tissue sarcoma treated with sorafenib within a named patient program in Austria. Twelve physicians from eight different hospitals provided records for the analysis of data. Among the 33 patients, the predominant histological subtype of sarcoma was leiomyosarcoma (n=18, 55%). Other subtypes were represented by only one or two cases. Fifteen patients presented with metastases at the time of diagnosis. Another 17 patients developed metastases later in the course of the disease (data on one patient are missing). Most of the 33 patients had undergone resection of the primary (n=29, 88%) and half of the patients had received radiotherapy (n=17, 52%). Chemotherapy for metastatic disease had been administered to 30 patients (91%). The majority had received two or more regimens of chemotherapy (n=25, 76%) before sorafenib treatment. The use of sorafenib resulted in a median time to treatment failure of 92 days in patients with leiomyosarcoma and 45 days in patients with other histological subtypes. One-third of the patients derived benefits from treatment: four patients were documented with partial response and six with stabilized disease. In terms of treatment-related toxicity, skin problems of various degrees and gastrointestinal disturbances were frequently reported. In this retrospective analysis of heavily pretreated patients with advanced soft tissue sarcomas, sorafenib was associated with some antitumor activity and an acceptable toxicity profile. PMID:24667659

  19. CXCR2 Inhibition Combined with Sorafenib Improved Antitumor and Antiangiogenic Response in Preclinical Models of Ovarian Cancer

    PubMed Central

    Devapatla, Bharat; Sharma, Ankur; Woo, Sukyung

    2015-01-01

    Antiangiogenic therapy is important for the treatment of gynecological cancer. However, the therapeutic benefit derived from these treatments is transient, predominantly due to the selective activation of compensatory proangiogenic pathways that lead to rapid development of resistance. We aimed to identify and target potential alternative signaling to anti-vascular endothelial growth factor (VEGF) therapy, with a view toward developing a combination of antiangiogenic agents to provide extended therapeutic benefits. We developed a preclinical in vivo phenotypic resistance model of ovarian cancer resistant to antiangiogenic therapy. We measured dynamic changes in secreted chemokines and angiogenic signaling in tumors and plasma in response to anti-VEGF treatment, as tumors advanced from the initial responsive phase to progressive disease. In tumors that progressed following sorafenib treatment, gene and protein expression levels of proangiogenic CXC chemokines and their receptors were significantly elevated, compared with responsive tumors. The chemokine (C-X-C motif) ligand 8 (CXCL8), also known as interleukin-8 (IL-8) increase was time-dependent and coincided with the dynamics of tumor progression. We used SB225002, a pharmacological inhibitor of chemokine (C-X-C motif) receptor 2 (CXCR2), to disrupt the CXC chemokine-mediated functions of ovarian cancer cells in in vitro assays of cell growth inhibition, spheroid formation, and cell migration. The combination of CXCR2 inhibitor with sorafenib led to a synergistic inhibition of cell growth in vitro, and further stabilized tumor progression following sorafenib in vivo. Our results suggest that CXCR2-mediated chemokines may represent an important compensatory pathway that promotes resistance to antiangiogenic therapy in ovarian cancer. Thus, simultaneous blockage of this proangiogenic cytokine pathway using CXCR2 inhibitors and the VEGF receptor (VEGFR) pathway could improve the outcomes of antiangiogenic therapy

  20. CXCR2 Inhibition Combined with Sorafenib Improved Antitumor and Antiangiogenic Response in Preclinical Models of Ovarian Cancer.

    PubMed

    Devapatla, Bharat; Sharma, Ankur; Woo, Sukyung

    2015-01-01

    Antiangiogenic therapy is important for the treatment of gynecological cancer. However, the therapeutic benefit derived from these treatments is transient, predominantly due to the selective activation of compensatory proangiogenic pathways that lead to rapid development of resistance. We aimed to identify and target potential alternative signaling to anti-vascular endothelial growth factor (VEGF) therapy, with a view toward developing a combination of antiangiogenic agents to provide extended therapeutic benefits. We developed a preclinical in vivo phenotypic resistance model of ovarian cancer resistant to antiangiogenic therapy. We measured dynamic changes in secreted chemokines and angiogenic signaling in tumors and plasma in response to anti-VEGF treatment, as tumors advanced from the initial responsive phase to progressive disease. In tumors that progressed following sorafenib treatment, gene and protein expression levels of proangiogenic CXC chemokines and their receptors were significantly elevated, compared with responsive tumors. The chemokine (C-X-C motif) ligand 8 (CXCL8), also known as interleukin-8 (IL-8) increase was time-dependent and coincided with the dynamics of tumor progression. We used SB225002, a pharmacological inhibitor of chemokine (C-X-C motif) receptor 2 (CXCR2), to disrupt the CXC chemokine-mediated functions of ovarian cancer cells in in vitro assays of cell growth inhibition, spheroid formation, and cell migration. The combination of CXCR2 inhibitor with sorafenib led to a synergistic inhibition of cell growth in vitro, and further stabilized tumor progression following sorafenib in vivo. Our results suggest that CXCR2-mediated chemokines may represent an important compensatory pathway that promotes resistance to antiangiogenic therapy in ovarian cancer. Thus, simultaneous blockage of this proangiogenic cytokine pathway using CXCR2 inhibitors and the VEGF receptor (VEGFR) pathway could improve the outcomes of antiangiogenic therapy

  1. Degradation of topoisomerase I induced by topoisomerase I inhibitors is dependent on inhibitor structure but independent of cell death.

    PubMed

    Fu, Q; Kim, S W; Chen, H X; Grill, S; Cheng, Y C

    1999-04-01

    DNA topoisomerase I (top I) is the target of the antitumor drug camptothecin (CPT) and its analogs. CPT induces dose- and time-dependent degradation of top I. Degradation of top I also occurs in a CPT-resistant cell line and, therefore, is not a consequence of cell death. Top I degradation is preceded by the appearance of a high molecular weight ladder of top I immunoreactivity and can be blocked by specific inhibitors of the proteasome. We compared the effects of five top I poisons [CPT, topotecan, 6-N-formylamino-12,13-dihydro-1, 11-dihydroxy-13-(beta-D-glucopyranosyl)-5H-indolo[2,3-a]pyrrolo[3, 4-c]carbazole-5,7(6H)-dione (NB506), camptothecin-(para)-4beta-amino-4'-O-demethyl Epipodophyllotoxin (W1), and camptothecin-(ortho)-4beta-amino-4'-O-demethyl Epipodophyllotoxin (W2)] on cleavable complex formation and top I degradation. Although all five drugs induced cleavable complex formation, two of the drugs, NB506 and W1 did not induce top I degradation. PMID:10101025

  2. Combining BET and HDAC inhibitors synergistically induces apoptosis of melanoma and suppresses AKT and YAP signaling

    PubMed Central

    Heinemann, Anja; Cullinane, Carleen; De Paoli-Iseppi, Ricardo; Wilmott, James S.; Gunatilake, Dilini; Madore, Jason; Strbenac, Dario; Yang, Jean Y.; Gowrishankar, Kavitha; Tiffen, Jessamy C.; Prinjha, Rab K.; Smithers, Nicholas; McArthur, Grant A.; Hersey, Peter; Gallagher, Stuart J.

    2015-01-01

    Histone acetylation marks have an important role in controlling gene expression and are removed by histone deacetylases (HDACs). These marks are read by bromodomain and extra-terminal (BET) proteins and novel inhibitiors of these proteins are currently in clinical development. Inhibitors of HDAC and BET proteins have individually been shown to cause apoptosis and reduce growth of melanoma cells. Here we show that combining the HDAC inhibitor LBH589 and BET inhibitor I-BET151 synergistically induce apoptosis of melanoma cells but not of melanocytes. Induction of apoptosis proceeded through the mitochondrial pathway, was caspase dependent and involved upregulation of the BH3 pro-apoptotic protein BIM. Analysis of signal pathways in melanoma cell lines resistant to BRAF inhibitors revealed that treatment with the combination strongly downregulated anti-apoptotic proteins and proteins in the AKT and Hippo/YAP signaling pathways. Xenograft studies showed that the combination of inhibitors was more effective than single drug treatment and confirmed upregulation of BIM and downregulation of XIAP as seen in vitro. These results support the combination of these two classes of epigenetic regulators in treatment of melanoma including those resistant to BRAF inhibitors. PMID:26087189

  3. In vivo pharmacological evaluation of two novel type II (inducible) nitric oxide synthase inhibitors.

    PubMed

    Tracey, W R; Nakane, M; Basha, F; Carter, G

    1995-05-01

    Selective type II (inducible) nitric oxide synthase (NOS) inhibitors have several potential therapeutic applications, including treatment of sepsis, diabetes, and autoimmune diseases. The ability of two novel, selective inhibitors of type II NOS, S-ethylisothiourea (EIT) and 2-amino-5,6-dihydro-6-methyl-4H-1,3-thiazine (AMT), to inhibit type II NOS function in vivo was studied in lipopolysaccharide (LPS) treated rats. Type II NOS activity was assessed by measuring changes in plasma nitrite and nitrate concentrations ([NOx]). Both EIT and AMT elicited a dose-dependent and > 95% inhibition of the LPS-induced increase in plasma [NOx]. The ED50 values for EIT and AMT were 0.4 and 0.2 mg/kg, respectively. In addition, the administration of LPS and either NOS inhibitor resulted in a dose-dependent increase in animal mortality; neither compound was lethal when administered alone. Pretreatment with L-arginine (but not D-arginine) prevented the mortality, while not affecting the type II NOS-dependent NO production, suggesting the toxicity may be due to inhibition of one of the other NOS isoforms (endothelial or neuronal). Thus, although EIT and AMT are potent inhibitors of type II NOS function in vivo, type II NOS inhibitors of even greater selectivity may need to be developed for therapeutic applications. PMID:7585335

  4. Encapsulation-Induced Stress Helps Saccharomyces cerevisiae Resist Convertible Lignocellulose Derived Inhibitors

    PubMed Central

    Westman, Johan O.; Manikondu, Ramesh Babu; Franzén, Carl Johan; Taherzadeh, Mohammad J.

    2012-01-01

    The ability of macroencapsulated Saccharomyces cerevisiae CBS8066 to withstand readily and not readily in situ convertible lignocellulose-derived inhibitors was investigated in anaerobic batch cultivations. It was shown that encapsulation increased the tolerance against readily convertible furan aldehyde inhibitors and to dilute acid spruce hydrolysate, but not to organic acid inhibitors that cannot be metabolized anaerobically. Gene expression analysis showed that the protective effect arising from the encapsulation is evident also on the transcriptome level, as the expression of the stress-related genes YAP1, ATR1 and FLR1 was induced upon encapsulation. The transcript levels were increased due to encapsulation already in the medium without added inhibitors, indicating that the cells sensed low stress level arising from the encapsulation itself. We present a model, where the stress response is induced by nutrient limitation, that this helps the cells to cope with the increased stress added by a toxic medium, and that superficial cells in the capsules degrade convertible inhibitors, alleviating the inhibition for the cells deeper in the capsule. PMID:23109889

  5. Amelioration of cyclosporine induced nephrotoxicity by dipeptidyl peptidase inhibitor vildagliptin.

    PubMed

    Ateyya, Hayam

    2015-09-01

    Cyclosporine A (CsA) is an immunosuppressive drug used in organ transplantation and autoimmune diseases but its clinical uses may be limited due to its dose-related nephrotoxicity. This study was carried out to evaluate the possible protective effects of vildagliptin (VLD) against CsA-induced nephrotoxicity in rats. Animals were divided into four groups treated as follows: control group (CsA & VLD vehicle); VLD group (10mg/kg/day, orally); CsA group (20mg/kg in sunflower oil, S.C.); and CsA-VLD group (CsA &VLD). Induced nephrotoxicity was evidenced by a significant elevation of serum creatinine, blood urea nitrogen (BUN), lactate dehydrogenase (LDH) and urinary micro total proteins (MTP), while serum albumin and urinary creatinine clearance were significantly decreased compared to the control group. Moreover, renal dysfunction was further confirmed by a significant increase in renal lipid peroxide that was measured as renal malondialdehyde (MDA). Renal reduced glutathione (GSH) and superoxide dismutase (SOD) were significantly decreased. Nephrotoxicity was further confirmed by renal tissue histopathology. Also, a high protein expression of Bax with decreased Bcl-2 was revealed in the renal tissue of the CsA treated group. Administration of VLD significantly ameliorated the nephrotoxic effects of CsA suggesting antioxidant, anti-inflammatory and anti-apoptotic benefits of VLD in CsA-induced nephrotoxicity. PMID:26225924

  6. The interaction between Helminthosporium carbonum and maize: Induced resistance and the role of an inhibitor

    SciTech Connect

    Cantone, F.A.

    1989-01-01

    Helminthosporium carbonum race 1 produces large, necrotic lesions on susceptible leaves of maize, whereas race 2 causes small, chlorotic flecks. Resistance to race 1 on susceptible leaves was induced when race 2 was inoculated for at least 10 h prior to a challenge inoculation with the pathogen and was manifest as a decrease in the number of appressoria and reduced penetration by race 1 conidia. Induced resistance was prevented or reversed when HC-toxin was added to challenge race 1 inoculum. The basis for protection appears to be a volatile, inhibitory compound produced by the host. This inhibitor was always associated with treatments that resulted in resistance, whereas no inhibitory activity was detected in diffusates from susceptible reactions. The appearance of inhibitor in diffusates coincided with the appearance of protection on the leaf. In addition to race 2 of H. carbonum, other fungi (H. victoriae, H. turcicum, and Alternaria) also induced production of the inhibitor as well as resistance to race 1. The inhibitor prevented the germination of conidia of all fungi tested. The growth of two phytopathogenic bacteria was also completely inhibited. Incorporation of {sup 3}H-leucine and {sup 14}C-uridine into protein and RNA, respectively, by conidia of H. carbonum was prevented within 15 min of exposure to inhibitor. In addition, respiration of conidia in inhibitor was reduced within 90 min to just 25% of the rate of conidia germinated in water. However, inhibitory activity of the diffusates was readily reversed when conidia were rinsed with water or when organic or amino acids were added to inhibited conidia. The addition of sodium acetate to race 2 and race 1 inocula resulted in lesion enlargement and also nullified inhibitory activity in vitro.

  7. IKK inhibitor suppresses epithelial-mesenchymal transition and induces cell death in prostate cancer.

    PubMed

    Ping, Hao; Yang, Feiya; Wang, Mingshuai; Niu, Yinong; Xing, Nianzeng

    2016-09-01

    IκB kinase (IKK)/nuclear factor κB (NF-κB) pathway activation is a key event in the acquisition of invasive and metastatic capacities in prostate cancer. A potent small-molecule compound, BMS-345541, was identified as a highly selective IKKα and IKKβ inhibitor to inhibit kinase activity. This study explored the effect of IKK inhibitor on epithelial-mesenchymal transition (EMT), apoptosis and metastasis in prostate cancer. Here, we demonstrate the role of IKK inhibitor reducing proliferation and inducing apoptosis in PC-3 cells. Furthermore, BMS345541 inhibited IκBα phosphorylation and nuclear level of NF-κB/p65 in PC-3 cells. We also observed downregulation of the N-cadherin, Snail, Slug and Twist protein in a dose-dependent manner. BMS‑345541 induced upregulation of the epithelial marker E-cadherin and phosphorylated NDRG1 at protein level. Moreover, BMS‑345541 reduced invasion and metastasis of PC-3 cells in vitro. In conclusion, IKK has a key role in both EMT and apoptosis of prostate cancer. IKK inhibitor can reverse EMT and induce cell death in PCa cells. IKK was identified as a potential target structure for future therapeutic intervention in PCa. PMID:27432067

  8. Exercise-induced ventricular arrhythmias in congestive heart failure and role of ACE inhibitors.

    PubMed

    Hasija, P K; Karloopia, S D; Shahi, B N; Chauhan, S S

    1998-02-01

    Ventricular arrhythmias are considered to be related to left ventricular (LV) dysfunction. ACE inhibitors though improve LV function their beneficial role on exercise-induced ventricular arrhythmias is not established. To study the effects of ACE inhibitors on exercise capacity vis-a-vis their role on exercise-induced ventricular arrhythmias, 25 patients of congestive heart failure (CHF) of various etiologies in NYHA Class II and III were subjected to a prospective randomised controlled trial. The control group comprising of 12 patients received conventional treatment (digitalis and diuretics) and the test group was given enalapril/captopril in addition as tolerated. They were followed up for 3 months. Exercise testing on treadmill and monitoring of clinical and biochemical parameters were done at the beginning and end of study in all cases. Ventricular arrhythmias observed during exercise and post-exercise for 10 minutes was analysed using Lown's grading for frequency and severity of ventricular arrhythmia. The mean exercise duration showed significant improvement on ACE inhibitor as compared to the control group (p < 0.05) however there was no significant change in the grades of arrhythmia. Serum electrolytes and other bio-chemical parameter were within normal range. It is concluded that effect of ACE inhibitor on improving functional capacity in CHF is independent of it's any effect on exercise-induced ventricular arrhythmias. PMID:11273109

  9. NOVEL ATYPICAL PKC INHIBITORS PREVENT VASCULAR ENDOTHELIAL GROWTH FACTOR-INDUCED BLOOD-RETINAL BARRIER DYSFUNCTION

    PubMed Central

    Titchenell, Paul M.; Lin, Cheng-Mao; Keil, Jason M.; Sundstrom, Jeffrey M.; Smith, Charles D.; Antonetti, David A.

    2013-01-01

    SYNOPSIS Pro-inflammatory cytokines and growth factors such as vascular endothelial growth factor (VEGF) contribute to the loss of the blood-retinal barrier (BRB) and subsequent macular edema in various retinal pathologies. VEGF signaling requires conventional PKC (PKCβ) activity; however, PKCβ inhibition only partially prevents VEGF-induced endothelial permeability and does not affect pro-inflammatory cytokine-induced permeability suggesting the involvement of alternative signaling pathways. Here, we provide evidence for the involvement of atypical protein kinase C (aPKC) signaling in VEGF-induced endothelial permeability and identify a novel class of inhibitors of aPKC that prevent BRB breakdown in vivo. Genetic and pharmacological manipulations of aPKC isoforms were used to assess their contribution to endothelial permeability in culture. A chemical library was screened using an in vitro kinase assay to identify novel small molecule inhibitors and further medicinal chemistry was performed to delineate a novel pharmacophore. We demonstrate that aPKC isoforms are both sufficient and required for VEGF-induced endothelial permeability. Furthermore, these specific, potent, non-competitive, small molecule inhibitors prevented VEGF-induced tight junction internalization and retinal endothelial permeability in response to VEGF in both primary culture and in rodent retina. These data suggest that aPKC inhibition with 2-amino-4-phenyl-thiophene derivatives may be developed to preserve the BRB in retinal diseases such as diabetic retinopathy or uveitis and the blood-brain barrier (BBB) in the presence of brain tumors. PMID:22721706

  10. Natural antioxidants as inhibitors of oxygen species induced mutagenicity.

    PubMed

    Minnunni, M; Wolleb, U; Mueller, O; Pfeifer, A; Aeschbacher, H U

    1992-10-01

    A ternary antioxidant vitamin mix consisting of ascorbic acid, alpha-tocopherol and lecithin as well as a rosemary extract with carnosic acid and carnosol as the two major active ingredients were shown to exhibit strong antimutagenic effects in Ames tester strain TA102. This strain has been shown to be highly sensitive to reactive oxygen species. Mutagenicity was induced by the generation of oxygen radicals by tert-butyl-hydroperoxide (tBOOH) or hydrogen peroxide (H2O2); therefore, the antimutagenic property of the above substances was attributed to their antioxidant properties. In the case of the vitamin mix, ascorbic acid was held responsible for this inhibitory property, whereas for the rosemary extract carnosic acid was identified as the antimutagenic agent. Since oxygen radicals are known to be involved in the multiprocess of carcinogenicity, it is concluded that these antioxidants might exhibit anticarcinogenic properties. PMID:1383702

  11. Treatment with Dimethyl Fumarate attenuates calcineurin inhibitor-induced Nephrotoxicity

    PubMed Central

    Takasu, Chie; Vaziri, Nosratola D.; Li, Shiri; Robles, Lourdes; Vo, Kelly; Takasu, Mizuki; Pham, Christine; Liu, Shuman; Farzaneh, Seyed H.; Foster, Clarence E; Stamos, Michael J; Ichii, Hirohito

    2014-01-01

    Background Cyclosporine A (CsA) is an immunosuppressive drug which has been widely used to prevent rejection following organ transplantation. However, its therapeutic use is limited by nephrotoxicity, in part mediated by oxidative stress. The present study aims to investigate the protective effects of Dimethyl Fumarate (DMF) on CsA-induced nephrotoxicity by enhancing the antioxidant defense system. Methods Male Sprague-Dawley rats were treated with CsA (n=8, 20 mg/kg/day i.p.) orCsA + DMF (n=7, 50 mg/kg/day p.o.) for 28 days. Renal function, histopathology, malondialdehyde (MDA), myeloperoxidase (MPO) levels and anti-oxidant enzyme expression were determined. Results DMF co-treatment ameliorated CsA-induced renal dysfunction as evidenced by significant decrease in serum creatinine (CsA 0.79 ± 0.02 mg/dl vs. CsA + DMF 0.62 ± 0.04 mg/dl, P=0.001) and urea (CsA 66.9 ± 0.4 mg/dl vs. CsA + DMF 53.3 ± 2.6 mg/dl, P<0.0001) levels, as well as improvement of creatinine clearance. DMF also significantly decreased serum MDA and renal tissue MDA and MPO contents. The protein expression of NQO-1, a major cellular anti-oxidant and detoxifying enzyme was significantly enhanced by DMF administration in kidney. Conclusions Administration of DMF has a protective potential against CsA nephrotoxicity. The protection afforded by DMF is mediated in part through inhibiting oxidative stress and inflammation and enhancing the antioxidant capacity. PMID:25710612

  12. Sorafenib in advanced melanoma: a critical role for pharmacokinetics?

    PubMed Central

    Pécuchet, N; Lebbe, C; Mir, O; Billemont, B; Blanchet, B; Franck, N; Viguier, M; Coriat, R; Tod, M; Avril, M-F; Goldwasser, F

    2012-01-01

    Background: Inter-patient pharmacokinetic variability can lead to suboptimal drug exposure, and therefore might impact the efficacy of sorafenib. This study reports long-term pharmacokinetic monitoring of patients treated with sorafenib and a retrospective pharmacodynamic/pharmacokinetic analysis in melanoma patients. Patients and methods: Heavily pretreated patients with stage IV melanoma were started on sorafenib 400 mg twice daily (bid). In the absence of limiting toxicity, dose escalation of 200 mg bid levels was done every 2 weeks. Plasma sorafenib measurement was performed at each visit, allowing a retrospective pharmacodynamic/pharmacokinetic analysis for safety and efficacy. Results: In all, 19 of 30 patients underwent dose escalation over 400 mg bid, and 28 were evaluable for response. The overall disease control rate was 61% (95% confidence interval (CI): 42.6–78.8), including three confirmed responses (12%). Disease control rate and progression-free survival (PFS) were improved in patients with high vs low exposure (80% vs 32%, P=0.02, and 5.25 vs 2.5 months, P=0.005, hazard ratio (HR)=0.28 (95% CI: 0.11–0.73)). In contrast, drug dosing had no effect on PFS. In multivariate analysis, drug exposure was the only factor associated with PFS (HR=0.36 (95% CI: 0.13–0.99)). Diarrhoea and anorexia were correlated with drug dosing, while hypertension and hand–foot skin reaction were correlated with drug exposure. Conclusions: Although sorafenib had modest efficacy in melanoma, these results suggest a correlation between exposure and efficacy of sorafenib. Therefore, dose optimisation in patients with low exposure at standard doses should be evaluated in validated indications. PMID:22767146

  13. A novel histone deacetylase inhibitor Chidamide induces apoptosis of human colon cancer cells

    SciTech Connect

    Liu, Lin; Chen, Baoan; Qin, Shukui; Li, Suyi; He, Xiangming; Qiu, Shaomin; Zhao, Wei; Zhao, Hong

    2010-02-05

    Many studies have demonstrated that histone deacetylase (HDAC) inhibitors induce various tumor cells to undergo apoptosis, and such inhibitors have been used in different clinical trials against different human cancers. In this study, we designed and synthesized a novel HDAC inhibitor, Chidamide. We showed that Chidamide was able to increase the acetylation levels of histone H3 and to inhibit the PI3K/Akt and MAPK/Ras signaling pathways, which resulted in arresting colon cancer cells at the G1 phase of the cell cycle and promoting apoptosis. As a result, the proliferation of colon cancer cells was suppressed in vitro. Our data support the potential application of Chidamide as an anticancer agent in treating colon cancer. Future studies are needed to demonstrate its in vivo efficacy.

  14. Aromatase Inhibitor-Induced Erythrocytosis in a Patient Undergoing Hormonal Treatment for Breast Cancer

    PubMed Central

    Yeruva, Sri Lakshmi Hyndavi; Ogbonna, Onyekachi Henry; Oneal, Patricia

    2015-01-01

    Aromatase inhibitors (AIs) are most commonly used for breast cancer patients with hormone receptor positive disease. Although the side effect profile of aromatase inhibitors is well known, including common side effects like arthralgia, bone pain, arthritis, hot flashes, and more serious problems like osteoporosis, we present a case of an uncommon side effect of these medications. We report the case of a postmenopausal woman on adjuvant hormonal therapy with anastrozole after completing definitive therapy for stage IIIB estrogen receptor-positive breast cancer, who was referred to hematology service for evaluation of persistent erythrocytosis. Primary and known secondary causes of polycythemia were ruled out. On further evaluation, we found that her erythrocytosis began after initiation of anastrozole and resolved after it was discontinued. We discuss the pathophysiology of aromatase inhibitor-induced erythrocytosis and reference of similar cases reported in the literature. PMID:26137331

  15. Structural basis for induced-fit binding of Rho-kinase to the inhibitor Y-27632.

    PubMed

    Yamaguchi, Hiroto; Miwa, Yukiko; Kasa, Miyuki; Kitano, Ken; Amano, Mutsuki; Kaibuchi, Kozo; Hakoshima, Toshio

    2006-09-01

    Rho-kinase is a main player in the regulation of cytoskeletal events and a promising drug target in the treatment of both vascular and neurological disorders. Here we report the crystal structure of the Rho-kinase catalytic domain in complex with the specific inhibitor Y-27632. Comparison with the structure of PKA bound to this inhibitor revealed a potential induced-fit binding mode that can be accommodated by the phosphate binding loop. This binding mode resembles to that observed in the Rho-kinase-fasudil complex. A structural database search indicated that a pocket underneath the phosphate-binding loop is present that favors binding to a small aromatic ring. Introduction of such a ring group might spawn a new modification scheme of pre-existing protein kinase inhibitors for improved binding capability. PMID:16891330

  16. Novel Combination of Sorafenib and Celecoxib Provides Synergistic Anti-Proliferative and Pro-Apoptotic Effects in Human Liver Cancer Cells

    PubMed Central

    Lampiasi, Nadia; Cusimano, Antonella; Azzolina, Antonina; McCubrey, James A.; Montalto, Giuseppe

    2013-01-01

    Molecular targeted therapy has shown promise as a treatment for advanced hepatocellular carcinoma (HCC). Sorafenib, a multikinase inhibitor, recently received FDA approval for the treatment of advanced HCC. However, although sorafenib is well tolerated, concern for its safety has been expressed. Celecoxib (Celebrex®) is a selective cyclooxygenase-2 (COX-2) inhibitor which exhibits antitumor effects in human HCC cells. The present study examined the interaction between celecoxib and sorafenib in two human liver tumor cell lines HepG2 and Huh7. Our data showed that each inhibitor alone reduced cell growth and the combination of celecoxib with sorafenib synergistically inhibited cell growth and increased apoptosis. To better understand the molecular mechanisms underlying the synergistic antitumor activity of the combination, we investigated the expression profile of the combination-treated liver cancer cell lines using microarray analysis. Combination treatment significantly altered expression levels of 1,986 and 2,483 transcripts in HepG2 and Huh7 cells, respectively. Genes functionally involved in cell death, signal transduction and regulation of transcription were predominantly up-regulated, while genes implicated in metabolism, cell-cycle control and DNA replication and repair were mainly down-regulated upon treatment. However, combination-treated HCC cell lines displayed specificity in the expression and activity of crucial factors involved in hepatocarcinogenesis. The altered expression of some of these genes was confirmed by semi-quantitative and quantitative RT-PCR and by Western blotting. Many novel genes emerged from our transcriptomic analyses, and further functional analyses may determine whether these genes can serve as potential molecular targets for more effective anti-HCC strategies. PMID:23776502

  17. A novel role for the apoptosis inhibitor ARC in suppressing TNFα-induced regulated necrosis.

    PubMed

    Kung, G; Dai, P; Deng, L; Kitsis, R N

    2014-04-01

    TNFα signaling can promote apoptosis or a regulated form of necrosis. ARC (apoptosis repressor with CARD (caspase recruitment domain)) is an endogenous inhibitor of apoptosis that antagonizes both the extrinsic (death receptor) and intrinsic (mitochondrial/ER) apoptosis pathways. We discovered that ARC blocks not only apoptosis but also necrosis. TNFα-induced necrosis was abrogated by overexpression of wild-type ARC but not by a CARD mutant that is also defective for inhibition of apoptosis. Conversely, knockdown of ARC exacerbated TNFα-induced necrosis, an effect that was rescued by reconstitution with wild-type, but not CARD-defective, ARC. Similarly, depletion of ARC in vivo exacerbated necrosis caused by infection with vaccinia virus, which elicits severe tissue damage through this pathway, and sensitized mice to TNFα-induced systemic inflammatory response syndrome. The mechanism underlying these effects is an interaction of ARC with TNF receptor 1 that interferes with recruitment of RIP1, a critical mediator of TNFα-induced regulated necrosis. These findings extend the role of ARC from an apoptosis inhibitor to a regulator of the TNFα pathway and an inhibitor of TNFα-mediated regulated necrosis. PMID:24440909

  18. Retinal toxicity induced by small-molecule Hsp90 inhibitors in beagle dogs.

    PubMed

    Kanamaru, Chisako; Yamada, Yuichiro; Hayashi, Shuji; Matsushita, Tomochika; Suda, Atsushi; Nagayasu, Miho; Kimura, Kazuya; Chiba, Shuichi

    2014-02-01

    Heat shock protein 90 (Hsp90) is a constitutively expressed molecular chaperone and plays an important role in the folding of client proteins with key regulatory roles in growth, survival, differentiation and metastasis. Because inhibition of Hsp90 degrades multiple oncogenic client proteins, it is considered to be an attractive anticancer therapy, and clinical trials of several Hsp90 inhibitors have been carried out. In the present study, two structurally distinct Hsp90 inhibitors, CH5164840 and CH5449302, were orally administered to beagle dogs to evaluate systemic toxicity. CH5164840 induced symptoms that suggest visual disorder, and ophthalmological observation and electroretinography (ERG) revealed loss of pupillary light reflex and abnormal waveforms, respectively. Histopathological examination showed changes in the photoreceptor cell layer and the outer nuclear layer of retina. On the other hand, while there were no clinical symptoms related to visual disorder, animals treated with CH5449302 showed similar abnormalities of ERG responses and histopathological changes in the photoreceptor cell layer and the outer nuclear layer of retina. The visual symptoms and abnormalities of ERG responses were noted at an earlier stage or lower dose than other toxicities in both compounds. Considering that two structurally distinct Hsp90 inhibitors induced a retinal toxicity in dogs after repeated administration, and that visual disorders were also reported in some clinical trials of Hsp90 inhibitors, it would seem highly likely that Hsp90 inhibition induces retinal toxicity. Also, our study indicated that a detailed ocular examination to evaluate the safety of Hsp90 inhibitors would be useful in both preclinical and clinical studies. PMID:24418710

  19. Pulsed EPR Characterization of HIV-1 Protease Conformational Sampling and Inhibitor-Induced Population Shifts

    PubMed Central

    Liu, Zhanglong; Casey, Thomas M.; Blackburn, Mandy E.; Huang, Xi; Pham, Linh; de Vera, Ian Mitchelle S.; Carter, Jeffrey D.; Kear-Scott, Jamie L.; Veloro, Angelo M.; Galiano, Luis; Fanucci, Gail E.

    2015-01-01

    The conformational landscape of HIV-1 protease (PR) can be experimentally characterized by pulsed-EPR double electron-electron resonance (DEER). For this characterization, nitroxide spin labels are attached to an engineered cysteine residue in the flap region of HIV-1 PR. DEER distance measurements from spin-labels contained within each flap of the homodimer provide a detailed description of the conformational sampling of apo-enzyme as well as induced conformational shifts as a function inhibitor binding. The distance distribution profiles are further interpreted in terms of a conformational ensemble scheme that consists of four unique states termed “curled/tucked”, “closed”, “semi-open” and “wide-open” conformations. Reported here are the DEER results for a drug-resistant variant clinical isolate sequence, V6, in the presence of FDA approved protease inhibitors (PIs) as well as a non-hydrolyzable substrate mimic, CaP2. Results are interpreted in the context of the current understanding of the relationship between conformational sampling, drug resistance, and kinetic efficiency of HIV-1PR as derived from previous DEER and kinetic data for a series of HIV-1PR constructs that contain drug-pressure selected mutations or natural polymorphisms. Specifically, these collective results support the notion that inhibitor-induced closure of the flaps correlates with inhibitor efficiency and drug resistance. This body of work also suggests DEER as a tool for studying conformational sampling in flexible enzymes as it relates to function. PMID:26489725

  20. Pulsed EPR characterization of HIV-1 protease conformational sampling and inhibitor-induced population shifts.

    PubMed

    Liu, Zhanglong; Casey, Thomas M; Blackburn, Mandy E; Huang, Xi; Pham, Linh; de Vera, Ian Mitchelle S; Carter, Jeffrey D; Kear-Scott, Jamie L; Veloro, Angelo M; Galiano, Luis; Fanucci, Gail E

    2016-02-17

    The conformational landscape of HIV-1 protease (PR) can be experimentally characterized by pulsed-EPR double electron-electron resonance (DEER). For this characterization, nitroxide spin labels are attached to an engineered cysteine residue in the flap region of HIV-1 PR. DEER distance measurements from spin-labels contained within each flap of the homodimer provide a detailed description of the conformational sampling of apo-enzyme as well as induced conformational shifts as a function of inhibitor binding. The distance distribution profiles are further interpreted in terms of a conformational ensemble scheme that consists of four unique states termed "curled/tucked", "closed", "semi-open" and "wide-open" conformations. Reported here are the DEER results for a drug-resistant variant clinical isolate sequence, V6, in the presence of FDA approved protease inhibitors (PIs) as well as a non-hydrolyzable substrate mimic, CaP2. Results are interpreted in the context of the current understanding of the relationship between conformational sampling, drug resistance, and kinetic efficiency of HIV-1PR as derived from previous DEER and kinetic data for a series of HIV-1PR constructs that contain drug-pressure selected mutations or natural polymorphisms. Specifically, these collective results support the notion that inhibitor-induced closure of the flaps correlates with inhibitor efficiency and drug resistance. This body of work also suggests DEER as a tool for studying conformational sampling in flexible enzymes as it relates to function. PMID:26489725

  1. Inhibitors of hypoxia-inducible factor 1 block breast cancer metastatic niche formation and lung metastasis.

    PubMed

    Wong, Carmen Chak-Lui; Zhang, Huafeng; Gilkes, Daniele M; Chen, Jasper; Wei, Hong; Chaturvedi, Pallavi; Hubbi, Maimon E; Semenza, Gregg L

    2012-07-01

    Intratumoral hypoxia, a frequent finding in metastatic cancer, results in the activation of hypoxia-inducible factors (HIFs). HIFs are implicated in many steps of breast cancer metastasis, including metastatic niche formation through increased expression of lysyl oxidase (LOX) and lysyl oxidase-like (LOXL) proteins, enzymes that remodel collagen at the metastatic site and recruit bone marrow-derived cells (BMDCs) to the metastatic niche. We investigated the effect of two chemically and mechanistically distinct HIF inhibitors, digoxin and acriflavine, on breast cancer metastatic niche formation. Both drugs blocked the hypoxia-induced expression of LOX and LOXL proteins, collagen cross-linking, CD11b⁺ BMDC recruitment, and lung metastasis in an orthotopic breast cancer model. Patients with HIF-1 α-overexpressing breast cancers are at increased risk of metastasis and mortality and our results suggest that such patients may benefit from aggressive therapy that includes a HIF inhibitor. PMID:22231744

  2. Effects of the inducible nitric oxide synthase inhibitor aminoguanidine in two different rat models of schizophrenia.

    PubMed

    Lafioniatis, Anastasios; Orfanidou, Martha A; Papadopoulou, Evangelia S; Pitsikas, Nikolaos

    2016-08-01

    Several lines evidence indicate that the non-competitive N-methyl-d-aspartate (NMDA) receptor antagonist ketamine and the mixed dopamine (DA) D1/D2 receptor agonist apomorphine induce schizophrenia-like symptoms in rodents, including memory impairments and social withdrawal. Nitric oxide (NO) has been proposed to act as an intracellular messenger in the brain and its overproduction is associated with schizophrenia. The current study was designed to investigate the ability of the inducible NO synthase (iNOS) inhibitor aminoguanidine (AG) to counteract schizophrenia-like behavioural deficits produced by ketamine and apomorphine in rats. The efficacy of AG to antagonize extinction of recognition memory, ketamine and apomorphine-induced recognition memory impairments was tested utilizing the novel object recognition task (NORT). Further, the efficacy of AG to attenuate ketamine-induced social withdrawal was examined in the social interaction test. AG (25 and 50mg/kg) antagonized extinction of recognition memory and reversed ketamine (3mg/kg) and apomorphine (1mg/kg)-induced recognition memory deficits. In contrast, AG (50 and 100mg/kg) did not counteract the ketamine (8mg/kg)-induced social isolation. The present data show that the iNOS inhibitor AG counteracted extinction of recognition memory and reversed recognition memory deficits produced by dysfunction of the glutamatergic and the dopaminergic (DAergic) system in rats. Therefore, AG may be efficacious in attenuating memory impairments often observed in schizophrenia patients. PMID:27132765

  3. Optimal combination of gemcitabine, sorafenib, and S-1 shows increased efficacy in treating cholangiocarcinoma in vitro and in vivo.

    PubMed

    Li, Hao; Zhang, Zhengyun; Zhou, Zunqiang; Ding, Xianting; Zhou, Guangwen

    2016-08-01

    Cholangiocarcinoma (CCA) is one of the most difficult cancers to treat and lacks an established standard chemotherapy regimen. This study evaluated the effects of different combinations of gemcitabine, sorafenib, and S-1 on CCA cells to identify the optimal drug combination. A fractional factorial design method was applied in drug combination experiments to determine the optimal combination of these three drugs (gemcitabine=1.4 mmol/l, sorafenib=0.03 mmol/l, S-1=0.185 mmol/l). We constructed a mathematical model with a small number of runs (Y=1.14-0.377A-23.0B-1.81C+0.084A+109B+6.06C+3.83AB+0.175AC-40.4BC) to predict the efficacy of combinations of the drugs. The optimal combination can significantly inhibit the AKT/mTOR pathway, and thus CCA cell proliferation, and can induce cell apoptosis. In vivo, this combination (gemcitabine=1.4 mmol/l, sorafenib=0.03 mmol/l, S-1=0.185 mmol/l) can significantly inhibit tumor growth. The present study showed that the mathematical model was reliable and could predict the efficacy of the different drug combinations. The optimal combination of these drugs may aid the development of a promising standard chemotherapy regimen for CCA. PMID:27035747

  4. The Calpain Inhibitor MDL28170 Induces the Expression of Apoptotic Markers in Leishmania amazonensis Promastigotes

    PubMed Central

    Marinho, Fernanda A.; Gonçalves, Keyla C. S.; Oliveira, Simone S. C.; Gonçalves, Diego S.; Matteoli, Filipe P.; Seabra, Sergio H.; Oliveira, Ana Carolina S.; Bellio, Maria; Oliveira, Selma S.; Souto-Padrón, Thaïs; d'Avila-Levy, Claudia M.; Santos, André L. S.; Branquinha, Marta H.

    2014-01-01

    Background Human cutaneous leishmaniasis is caused by distinct species, including Leishmania amazonensis. Treatment of cutaneous leishmaniasis is far from satisfactory due to increases in drug resistance and relapses, and toxicity of compounds to the host. As a consequence for this situation, the development of new leishmanicidal drugs and the search of new targets in the parasite biology are important goals. Methodology/Principal Findings In this study, we investigated the mechanism of death pathway induced by the calpain inhibitor MDL28170 on Leishmania amazonensis promastigote forms. The combined use of different techniques was applied to contemplate this goal. MDL28170 treatment with IC50 (15 µM) and two times the IC50 doses induced loss of parasite viability, as verified by resazurin assay, as well as depolarization of the mitochondrial membrane, which was quantified by JC-1 staining. Scanning and transmission electron microscopic images revealed drastic alterations on the parasite morphology, some of them resembling apoptotic-like death, including cell shrinking, surface membrane blebs and altered chromatin condensation pattern. The lipid rearrangement of the plasma membrane was detected by Annexin-V labeling. The inhibitor also induced a significant increase in the proportion of cells in the sub-G0/G1 phase, as quantified by propidium iodide staining, as well as genomic DNA fragmentation, detected by TUNEL assay. In cells treated with MDL28170 at two times the IC50 dose, it was also possible to observe an oligonucleossomal DNA fragmentation by agarose gel electrophoresis. Conclusions/Significance The data presented in the current study suggest that MDL28170 induces apoptotic marker expression in promastigotes of L. amazonensis. Altogether, the results described in the present work not only provide a rationale for further exploration of the mechanism of action of calpain inhibitors against trypanosomatids, but may also widen the investigation of the

  5. Vascular Endothelial Growth Factor Inhibitor-Induced Hypertension: Basics for Primary Care Providers

    PubMed Central

    Escalante, Carmen P.; Zalpour, Ali

    2011-01-01

    Frequently, primary care providers continue to manage the overall medical care of cancer patients. With newer and often more potent antitumor agents, patients may present to their local physicians with drug-induced toxicities such as hypertension induced by vascular endothelial growth factor (VEGF) inhibitors. It is imperative that these healthcare providers are aware of basic aspects of this drug class, as its use has increased significantly in the last several years. Uncontrolled or malignant hypertension due to these agents should be recognized readily and treated early to prevent more severe outcomes. This overview provides a brief background on the role of VEGF and angiogenesis in tumor metabolism as well as theories of the mechanism of VEGF inhibitors and hypertension. Helpful clinical practice aspects including the types of inhibitors used in the United States and their pharmacologic characteristics will be discussed. Also, diagnosis and treatment of hypertension induced by vascular endothelial growth factors are reviewed. A summary of key aspects of this drug class and hypertension is included. PMID:21629798

  6. Binding interaction between sorafenib and calf thymus DNA: spectroscopic methodology, viscosity measurement and molecular docking.

    PubMed

    Shi, Jie-Hua; Chen, Jun; Wang, Jing; Zhu, Ying-Yao

    2015-02-01

    The binding interaction of sorafenib with calf thymus DNA (ct-DNA) was studied using UV-vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism (CD), viscosity measurement and molecular docking methods. The experimental results revealed that there was obvious binding interaction between sorafenib and ct-DNA. The binding constant (Kb) of sorafenib with ct-DNA was 5.6×10(3) M(-1) at 298 K. The enthalpy and entropy changes (ΔH(0) and ΔS(0)) in the binding process of sorafenib with ct-DNA were -27.66 KJ mol(-1) and -21.02 J mol(-1) K(-1), respectively, indicating that the main binding interaction forces were van der Waals force and hydrogen bonding. The docking results suggested that sorafenib preferred to bind on the minor groove of A-T rich DNA and the binding site of sorafenib was 4 base pairs long. The conformation change of sorafenib in the sorafenib-DNA complex was obviously observed and the change was close relation with the structure of DNA, implying that the flexibility of sorafenib molecule played an important role in the formation of the stable sorafenib-ct-DNA complex. PMID:25311519

  7. Binding interaction between sorafenib and calf thymus DNA: Spectroscopic methodology, viscosity measurement and molecular docking

    NASA Astrophysics Data System (ADS)

    Shi, Jie-Hua; Chen, Jun; Wang, Jing; Zhu, Ying-Yao

    2015-02-01

    The binding interaction of sorafenib with calf thymus DNA (ct-DNA) was studied using UV-vis absorption spectroscopy, fluorescence emission spectroscopy, circular dichroism (CD), viscosity measurement and molecular docking methods. The experimental results revealed that there was obvious binding interaction between sorafenib and ct-DNA. The binding constant (Kb) of sorafenib with ct-DNA was 5.6 × 103 M-1 at 298 K. The enthalpy and entropy changes (ΔH0 and ΔS0) in the binding process of sorafenib with ct-DNA were -27.66 KJ mol-1 and -21.02 J mol-1 K-1, respectively, indicating that the main binding interaction forces were van der Waals force and hydrogen bonding. The docking results suggested that sorafenib preferred to bind on the minor groove of A-T rich DNA and the binding site of sorafenib was 4 base pairs long. The conformation change of sorafenib in the sorafenib-DNA complex was obviously observed and the change was close relation with the structure of DNA, implying that the flexibility of sorafenib molecule played an important role in the formation of the stable sorafenib-ct-DNA complex.

  8. Transcription inhibitors prevent amnesia induced by NMDA antagonist-mediated impairment of memory reconsolidation.

    PubMed

    Nikitin, Vladimir P; Solntseva, Svetlana V; Shevelkin, Alexey V

    2016-09-01

    Recent studies report that long-term memory retrieval can induce memory reconsolidation, and impairment of this reconsolidation might lead to amnesia. Previously, we found that reconsolidation of a conditioned food aversion memory could be disrupted by translation inhibitors for up to 3 h following a reconsolidation event, thus inducing amnesia. We examined the role of transcription processes in the induction of amnesia in the land snail, Helix lucorum. It received N-methyl-D-aspartate (NMDA) glutamate receptor antagonist and transcription inhibitor 2 days after learning in a neutral context environment; it was then transferred to the learning context followed by reminder with conditioned food stimulus. NMDA receptor blockade, followed by a reminder session, impaired reconsolidation of an aversive memory. Simultaneous administration of an NMDA receptor antagonist and a transcription inhibitor prior to reminder of an aversive event prevented amnesia induction. In contrast, when a transcription inhibitor alone was injected prior to a reminder session, the blockade had no effect on memory. We found that transcription inhibition 0-6 h after amnesia induction suppressed memory loss, but this suppression was lost when inhibitors were administered 9 h after amnesia. Thus, amnesia is likely dependent on transcription processes within a 9-h time window. We can hypothesize that amnesia induction initiates synthesis of specific mRNAs and proteins; furthermore, these events occur within specific time-dependent windows. Our findings could prove useful for the analysis of amnesia formation and for the development of possible ways to prevent memory loss associated with various diseases and injuries in animals and humans. PMID:26742927

  9. Effects of inhibitors on 1-methyladenine induced maturation of starfish oocytes

    NASA Astrophysics Data System (ADS)

    Lee, Harold H.; Xu, Quanhan

    1986-12-01

    1-methladenine (1-MA) induces starfish oocytes maturation via surface reaction followed by the appearance of a cytoplasmic maturation factor which in turn induces germinal vesicle breakdown (GVBD) to resume meiosis. Cellular mechanisms involved in GVBD were investigated by microinjection of metabolic inhibitors. Colchicine (Co) inhibited maturation, cytochalasin-B (CB) delayed GVBD and actinomycin-D-(Act-D) and puromycin (Pu) had no effect. It appears that the microtubule and the microfilament systems are associated with the nuclear membrane dissolution during the process of oocyte maturation of starfish.

  10. Further studies of auxin and ACC induced feminization in the cucumber plant using ethylene inhibitors

    NASA Technical Reports Server (NTRS)

    Takahashi, H.; Jaffe, M. J.

    1984-01-01

    The present study was designed to establish the role of an essential hormone controlling sex expression in cucumber. A potent anti-ethylene agent, AgNO3, completely inhibited pistillate flower formation caused by IAA, ACC or ethephon. Inhibitors of ethylene biosynthesis, AVG and CoCl2 also suppressed feminization due to exogenous IAA or ACC. Though AVG also suppressed ethephon-induced feminization, this may be due to the second effect of AVG rather than the effect on ACC biosynthesis. These results confirm that ethylene is a major factor regulating feminization and that exogenous auxin induces pistillate flower formation through its stimulation of ethylene production, rather than ACC production.

  11. Quantification of dynamic contrast-enhanced ultrasound in HCC: prediction of response to a new combination therapy of sorafenib and panobinostat in advanced hepatocellular carcinoma.

    PubMed

    Knieling, Ferdinand; Waldner, Maximilian J; Goertz, Ruediger S; Strobel, Deike

    2012-01-01

    Here, we report the case of a patient, who showed an antitumour response to a new combination therapy of sorafenib and the histon deacetylase inhibitor panobinostat (LBH-589). D-CEUS (Dynamic contrast-enhanced ultrasonography) was able to predict response to the new therapy regime and may be an interesting tool in the early evaluation of response to therapy. It might be especially useful to differentiate between responders and non-responders of new-targeted pharmaceuticals like multikinase inhibitors in hepatocellular carcinomas. PMID:23257272

  12. Next-generation proteasome inhibitor MLN9708 sensitizes breast cancer cells to doxorubicin-induced apoptosis

    PubMed Central

    Wang, Hao; Yu, Yang; Jiang, Zheng; Cao, Wen-Ming; Wang, Zhenyu; Dou, Jun; Zhao, Yanling; Cui, Yunfu; Zhang, Hong

    2016-01-01

    Doxorubicin (Dox), one of the most effective chemotherapy drug for cancer treatment, is limited by its severe side effects and chemoresistance. Dox induces DNA damage and leads to significant proteomic changes in the cancer cells, which makes the ubiquitin-proteasome system a potential target to enhance the efficacy of Dox therapy. The unsuccessful clinical trials of proteasome inhibitor PS-341 (bortezomib) in solid tumors led to the invention of MLN9708 (ixazomib), an orally bioavailable next-generation proteasome inhibitor with improved pharmacokinetic and pharmacodynamic features. In this preclinical study, we used eight human breast cancer cell lines, which represent the major molecular subtypes of breast cancer, to validate the cytotoxic effects of MLN9708, alone and in combination with Dox. We found that MLN9708 had cytotoxic effects, induced autophagy and MKP-1 expression, and enhanced Dox-induced apoptosis in these cell lines. MLN9708 also enhanced Dox-induced JNK and p38 phosphorylation and inhibited Dox-induced IκBα degradation. Our in vitro results suggest that MLN9708 has antitumor effects in breast cancer and can sensitize breast cancer cells to Dox treatment. This promising combination may be an effective and feasible therapeutic option for treating breast cancer and warrants clinical validation. PMID:27217076

  13. Histone Deacetylase Inhibitors Facilitate Dihydroartemisinin-Induced Apoptosis in Liver Cancer In Vitro and In Vivo

    PubMed Central

    Zhang, Chris Zhiyi; Pan, Yinghua; Cao, Yun; Lai, Paul B. S.; Liu, Lili; Chen, George Gong; Yun, Jingping

    2012-01-01

    Liver cancer ranks in prevalence and mortality among top five cancers worldwide. Accumulating interests have been focused in developing new strategies for liver cancer treatment. We have previously showed that dihydroartemisinin (DHA) exhibited antitumor activity towards liver cancer. In this study, we demonstrated that histone deacetylase inhibitors (HDACi) significantly augmented the antineoplastic effect of DHA via increasing apoptosis in vitro and in vivo. Inhibition of ERK phosphorylation contributed to DHA-induced apoptosis, due to the fact that inhibitor of ERK phosphorylation (PD98059) increased DHA-induced apoptosis. Compared with DHA alone, the combined treatment with DHA and HDACi reduced mitochondria membrane potential, released cytochrome c into cytoplasm, increased p53 and Bak, decreased Mcl-1 and p-ERK, activated caspase 3 and PARP, and induced apoptotic cells. Furthermore, we showed that HDACi pretreatment facilitated DHA-induced apoptosis. In Hep G2-xenograft carrying nude mice, the intraperitoneal injection of DHA and SAHA resulted in significant inhibition of xenograft tumors. Results of TUNEL and H&E staining showed more apoptosis induced by combined treatment. Immunohistochemistry data revealed the activation of PARP, and the decrease of Ki-67, p-ERK and Mcl-1. Taken together, our data suggest that the combination of HDACi and DHA offers an antitumor effect on liver cancer, and this combination treatment should be considered as a promising strategy for chemotherapy. PMID:22761917

  14. Next-generation proteasome inhibitor MLN9708 sensitizes breast cancer cells to doxorubicin-induced apoptosis.

    PubMed

    Wang, Hao; Yu, Yang; Jiang, Zheng; Cao, Wen-Ming; Wang, Zhenyu; Dou, Jun; Zhao, Yanling; Cui, Yunfu; Zhang, Hong

    2016-01-01

    Doxorubicin (Dox), one of the most effective chemotherapy drug for cancer treatment, is limited by its severe side effects and chemoresistance. Dox induces DNA damage and leads to significant proteomic changes in the cancer cells, which makes the ubiquitin-proteasome system a potential target to enhance the efficacy of Dox therapy. The unsuccessful clinical trials of proteasome inhibitor PS-341 (bortezomib) in solid tumors led to the invention of MLN9708 (ixazomib), an orally bioavailable next-generation proteasome inhibitor with improved pharmacokinetic and pharmacodynamic features. In this preclinical study, we used eight human breast cancer cell lines, which represent the major molecular subtypes of breast cancer, to validate the cytotoxic effects of MLN9708, alone and in combination with Dox. We found that MLN9708 had cytotoxic effects, induced autophagy and MKP-1 expression, and enhanced Dox-induced apoptosis in these cell lines. MLN9708 also enhanced Dox-induced JNK and p38 phosphorylation and inhibited Dox-induced IκBα degradation. Our in vitro results suggest that MLN9708 has antitumor effects in breast cancer and can sensitize breast cancer cells to Dox treatment. This promising combination may be an effective and feasible therapeutic option for treating breast cancer and warrants clinical validation. PMID:27217076

  15. Translation inhibitors induce formation of cholesterol ester-rich lipid droplets.

    PubMed

    Suzuki, Michitaka; Ohsaki, Yuki; Tatematsu, Tsuyako; Shinohara, Yuki; Maeda, Takashi; Cheng, Jinglei; Fujimoto, Toyoshi

    2012-01-01

    Lipid droplets (LDs) in non-adipocytes contain triglycerides (TG) and cholesterol esters (CE) in variable ratios. TG-rich LDs are generated when unsaturated fatty acids are administered, but the conditions that induce CE-rich LD formation are less well characterized. In the present study, we found that protein translation inhibitors such as cycloheximide (CHX) induced generation of CE-rich LDs and that TIP47 (perilipin 3) was recruited to the LDs, although the expression of this protein was reduced drastically. Electron microscopy revealed that LDs formed in CHX-treated cells possess a distinct electron-dense rim that is not found in TG-rich LDs, whose formation is induced by oleic acid. CHX treatment caused upregulation of mTORC1, but the CHX-induced increase in CE-rich LDs occurred even when rapamycin or Torin1 was given along with CHX. Moreover, the increase in CE was seen in both wild-type and autophagy-deficient Atg5-null mouse embryonic fibroblasts, indicating that mTORC1 activation and suppression of autophagy are not necessary to induce the observed phenomenon. The results showed that translation inhibitors cause a significant change in the lipid ester composition of LDs by a mechanism independent of mTORC1 signaling and autophagy. PMID:22879956

  16. The c-Met Inhibitor MSC2156119J Effectively Inhibits Tumor Growth in Liver Cancer Models.

    PubMed

    Bladt, Friedhelm; Friese-Hamim, Manja; Ihling, Christian; Wilm, Claudia; Blaukat, Andree

    2014-01-01

    The mesenchymal-epithelial transition factor (c-Met) is a receptor tyrosine kinase with hepatocyte growth factor (HGF) as its only high-affinity ligand. Aberrant activation of c-Met is associated with many human malignancies, including hepatocellular carcinoma (HCC). We investigated the in vivo antitumor and antimetastatic efficacy of the c-Met inhibitor MSC2156119J (EMD 1214063) in patient-derived tumor explants. BALB/c nude mice were inoculated with MHCC97H cells or with tumor fragments of 10 patient-derived primary liver cancer explants selected according to c-Met/HGF expression levels. MSC2156119J (10, 30, and 100 mg/kg) and sorafenib (50 mg/kg) were administered orally as single-agent treatment or in combination, with vehicle as control. Tumor response, metastases formation, and alpha fetoprotein (AFP) levels were measured. MSC2156119J inhibited tumor growth and induced complete regression in mice bearing subcutaneous and orthotopic MHCC97H tumors. AFP levels were undetectable after 5 weeks of MSC2156119J treatment, and the number of metastatic lung foci was reduced. Primary liver explant models with strong c-Met/HGF activation showed increased responsiveness to MSC2156119J, with MSC2156119J showing similar or superior activity to sorafenib. Tumors characterized by low c-Met expression were less sensitive to MSC2156119J. MSC2156119J was better tolerated than sorafenib, and combination therapy did not improve efficacy. These findings indicate that selective c-Met/HGF inhibition with MSC2156119J is associated with marked regression of c-Met high-expressing tumors, supporting its clinical development as an antitumor treatment for HCC patients with active c-Met signaling. PMID:25256830

  17. Apoptosis and antitumor effects induced by the combination of an mTOR inhibitor and an autophagy inhibitor in human osteosarcoma MG63 cells

    PubMed Central

    HORIE, RYOSUKE; NAKAMURA, OSAMU; YAMAGAMI, YOSHIKI; MORI, MASAKI; NISHIMURA, HIDEKI; FUKUOKA, NATSUKO; YAMAMOTO, TETSUJI

    2016-01-01

    The inhibition of the mammalian target of rapamycin (mTOR) signaling pathway promotes the initiation of autophagy. Although it remains under debate whether chemotherapy-induced autophagy in tumor cells is a protective response or is invoked to promote cell death, recent studies indicate that autophagy is a self-defense mechanism of cancer cells that are subjected to antitumor agents and that blocking autophagy can trigger apoptosis. The aim of this study was to examine the effects of rapamycin, an mTOR inhibitor, on MG63 osteosarcoma cells. We further examined whether the combination of rapamycin and the small molecule inhibitor of autophagy Spautin-1 (specific and potent autophagy inhibitor-1) enhanced the rapamycin-induced apoptosis in MG63 cells. We examined the effects of rapamycin treatment on cell proliferation, phosphorylation of mTOR pathway components, and autophagy by western blot analysis. Furthermore, we examined the effects of rapamycin with or without Spautin-1 on the induction of apoptosis by western blot analysis and immunohistochemical staining. We found that rapamycin inhibited cell proliferation and decreased the phosphorylation of mTOR pathway components in MG63 cells. Rapamycin induced the apoptosis of MG63 cells, and this apoptosis was enhanced by Spautin-1. It was considered that Spautin-1 suppressed the protective mechanism induced by rapamycin in tumor cells and induced apoptosis. Therefore, the combination of an mTOR inhibitor and an autophagy inhibitor may be effective in the treatment of osteosarcoma because it effectively induces the apoptotic pathway. PMID:26530936

  18. Cell Death Inducing Microbial Protein Phosphatase Inhibitors--Mechanisms of Action.

    PubMed

    Kleppe, Rune; Herfindal, Lars; Døskeland, Stein Ove

    2015-10-01

    Okadaic acid (OA) and microcystin (MC) as well as several other microbial toxins like nodularin and calyculinA are known as tumor promoters as well as inducers of apoptotic cell death. Their intracellular targets are the major serine/threonine protein phosphatases. This review summarizes mechanisms believed to be responsible for the death induction and tumor promotion with focus on the interdependent production of reactive oxygen species (ROS) and activation of Ca(2+)/calmodulin kinase II (CaM-KII). New data are presented using inhibitors of specific ROS producing enzymes to curb nodularin/MC-induced liver cell (hepatocyte) death. They indicate that enzymes of the arachidonic acid pathway, notably phospholipase A2, 5-lipoxygenase, and cyclooxygenases, may be required for nodularin/MC-induced (and presumably OA-induced) cell death, suggesting new ways to overcome at least some aspects of OA and MC toxicity. PMID:26506362

  19. Natural furocoumarins as inducers and inhibitors of cytochrome P450 1A1 in rat hepatocytes.

    PubMed

    Baumgart, Annette; Schmidt, Melanie; Schmitz, Hans-Joachim; Schrenk, Dieter

    2005-02-15

    Furocoumarins are natural plant constituents present in medicinal plants and in a variety of foods such as grapefruit juice. They are phototoxic and act as potent inhibitors of drug metabolism. We have investigated the interaction of four furocoumarins angelicin, bergamottin, isopimpinellin, and 8-methoxypsoralen with the expression and activity of aryl hydrocarbon receptor (AhR)-regulated CYP1A1 in rat hepatocytes in primary culture, both in the presence and absence of light. In intact hepatocytes pretreated with 2,3,7,8-tetrachlorodibenzo-p-dioxin and in microsomes isolated thereof, all furocoumarins tested acted as potent inhibitors of CYP1A1 activity bergamottin being the most potent inhibitor in microsomes with an IC(50) of 10 nM in the presence and 60 nM in the absence of light. 8-Methoxypsoralen and angelicin led to a significant induction of CYP1A1 mRNA in hepatocytes, while all furocoumarins except bergamottin increased xenobiotic-responsive element-driven reporter gene expression in transfected H4IIE rat hepatoma cells when light was excluded. Furthermore, all furocoumarins tested induced the expression of endogenous, immunoreactive CYP1A1 protein, primarily in the dark. In conclusion, our results demonstrate that individual furocoumarins present in food and medicinal plants can interfere with AhR-regulated CYP1A1 expression and activity in at least three major ways, i.e., (i) act as highly potent inhibitors of the catalytic activity of CYP1A1 both in the presence and absence of light, (ii) induce CYP1A1 gene expression in the absence of light via activation of the AhR, and (iii) induce CYP1A1 gene expression without activation of the AhR. PMID:15670584

  20. Methods for the Analyses of Inhibitor-Induced Aberrant Multimerization of HIV-1 Integrase

    PubMed Central

    Kessl, Jacques J.; Sharma, Amit; Kvaratskhelia, Mamuka

    2016-01-01

    HIV-1 integrase (IN) is an important therapeutic target as its function is essential for the viral lifecycle. The discovery of multifunctional allosteric IN inhibitors or ALLINIs, which potently impair viral replication by promoting aberrant, higher order IN multimerization as well as inhibit IN interactions with its cellular cofactor, LEDGF/p75, has opened new venues to exploit IN multimerization as a therapeutic target. Furthermore, the recent discovery of multimerization selective IN inhibitors or MINIs, has provided new investigational probes to study the direct effects of aberrant IN multimerization in vitro and in infected cells. Here we describe three complementary methods designed to detect and quantify the effects of these new classes of inhibitors on IN multimerization. These methods include a homogenous time-resolved fluorescence-based assay which allows for measuring EC50 values for the inhibitor-induced aberrant IN multimerization, a dynamic light scattering-based assay which allows for monitoring the formation and sizes of oligomeric IN particles in a time-dependent manner, and a chemical cross-linking-based assay of interacting IN subunits which allows for the determination of IN oligomers in viral particles. PMID:26714710

  1. Protection from impulse noise-induced hearing loss with novel Src-protein tyrosine kinase inhibitors

    PubMed Central

    Bielefeld, Eric C.; Hangauer, David; Henderson, Donald

    2011-01-01

    Apoptosis is a significant mechanism of cochlear hair cell loss from noise. Molecules that inhibit apoptotic intracellular signaling reduce cochlear damage and hearing loss from noise. The current study is an extension of a previous study of the protective value of Src-protein tyrosine kinase inhibitors against noise (Harris et al., 2005). The current study tested three Src-inhibitors: the indole-based KX1-141, the biaryl-based KX2-329, and the ATP-competitive KX2-328. Each of the three drugs was delivered into the chinchillas’ cochleae by allowing the solutions to diffuse across the round window membrane thirty minutes prior to exposure to impulse noise. Hearing thresholds were measured using auditory evoked responses from electrodes in the inferior colliculi. Ears treated with KX2-329 showed significantly lower threshold shifts and outer hair cell losses than the control group. The cochleae treated with KX1-141 and KX2-328 did not show statistically significant protection from the impulse noise. The finding of protection with KX2-329 demonstrates that a biaryl-based Src inhibitor has protective capacity against noise-induced hearing loss that is as good as that demonstrated by KX1-004, a Src inhibitor drug that has been studied extensively as an otoprotectant against noise, and suggests that KX2-329 could be useful for protection against noise. PMID:21840347

  2. Methods for the Analyses of Inhibitor-Induced Aberrant Multimerization of HIV-1 Integrase.

    PubMed

    Kessl, Jacques J; Sharma, Amit; Kvaratskhelia, Mamuka

    2016-01-01

    HIV-1 integrase (IN) is an important therapeutic target as its function is essential for the viral lifecycle. The discovery of multifunctional allosteric IN inhibitors or ALLINIs, which potently impair viral replication by promoting aberrant, higher order IN multimerization as well as inhibit IN interactions with its cellular cofactor, LEDGF/p75, has opened new venues to exploit IN multimerization as a therapeutic target. Furthermore, the recent discovery of multimerization selective IN inhibitors or MINIs, has provided new investigational probes to study the direct effects of aberrant IN multimerization in vitro and in infected cells. Here we describe three complementary methods designed to detect and quantify the effects of these new classes of inhibitors on IN multimerization. These methods include a homogenous time-resolved fluorescence-based assay which allows for measuring EC50 values for the inhibitor-induced aberrant IN multimerization, a dynamic light scattering-based assay which allows for monitoring the formation and sizes of oligomeric IN particles in a time-dependent manner, and a chemical cross-linking-based assay of interacting IN subunits which allows for the determination of IN oligomers in viral particles. PMID:26714710

  3. Proton pump inhibitor alone vs proton pump inhibitor plus mucosal protective agents for endoscopic submucosal dissection-induced ulcer: a systematic review and meta-analysis

    PubMed Central

    Nishizawa, Toshihiro; Suzuki, Hidekazu; Kanai, Takanori; Yahagi, Naohisa

    2015-01-01

    Mucosal protective agents may improve healing of patients with endoscopic submucosal dissection-induced ulcers. The present study systematically evaluated published clinical trials to determine whether combined therapeutic use of mucosal protective agents and proton pump inhibitors can improve the outcome of patients with endoscopic submucosal dissection-induced ulcers compared to treatment with proton pump inhibitors alone. PubMed, the Cochrane Library, and the Igaku-Chuo-Zasshi database were searched to identify eligible randomized trials for systematic review. We identified 11 randomized trials for inclusion in our study (1,160 patients). Pooled endoscopic submucosal dissection-induced ulcer healing rates were 45.8% and 34.4% for patients with or without mucosal protective agents, respectively. The odds ratio was 2.28 (95% confidence interval, 1.57–3.31) with no significant study heterogeneity. In conclusion, the systematic review and meta-analysis showed that the combined therapeutic use of proton pump inhibitors and mucosal protective agents improved healing rates of endoscopic submucosal dissection-induced ulcers compared to treatment with proton pump inhibitor monotherapy. PMID:25759512

  4. Inhibitor of apoptosis signal-regulating kinase 1 protects against acetaminophen-induced liver injury

    SciTech Connect

    Xie, Yuchao; Ramachandran, Anup; Breckenridge, David G.; Liles, John T.; Lebofsky, Margitta; Farhood, Anwar; Jaeschke, Hartmut

    2015-07-01

    Metabolic activation and oxidant stress are key events in the pathophysiology of acetaminophen (APAP) hepatotoxicity. The initial mitochondrial oxidative stress triggered by protein adduct formation is amplified by c-jun-N-terminal kinase (JNK), resulting in mitochondrial dysfunction and ultimately cell necrosis. Apoptosis signal-regulating kinase 1 (ASK1) is considered the link between oxidant stress and JNK activation. The objective of the current study was to assess the efficacy and mechanism of action of the small-molecule ASK1 inhibitor GS-459679 in a murine model of APAP hepatotoxicity. APAP (300 mg/kg) caused extensive glutathione depletion, JNK activation and translocation to the mitochondria, oxidant stress and liver injury as indicated by plasma ALT activities and area of necrosis over a 24 h observation period. Pretreatment with 30 mg/kg of GS-459679 almost completely prevented JNK activation, oxidant stress and injury without affecting the metabolic activation of APAP. To evaluate the therapeutic potential of GS-459679, mice were treated with APAP and then with the inhibitor. Given 1.5 h after APAP, GS-459679 was still protective, which was paralleled by reduced JNK activation and p-JNK translocation to mitochondria. However, GS-459679 treatment was not more effective than N-acetylcysteine, and the combination of GS-459679 and N-acetylcysteine exhibited similar efficacy as N-acetylcysteine monotherapy, suggesting that GS-459769 and N-acetylcysteine affect the same pathway. Importantly, inhibition of ASK1 did not impair liver regeneration as indicated by PCNA staining. In conclusion, the ASK1 inhibitor GS-459679 protected against APAP toxicity by attenuating JNK activation and oxidant stress in mice and may have therapeutic potential for APAP overdose patients. - Highlights: • Two ASK1 inhibitors protected against acetaminophen-induced liver injury. • The ASK1 inhibitors protect when used as pre- or post-treatment. • Protection by ASK1 inhibitor is

  5. Calpain Inhibitor PD150606 Attenuates Glutamate Induced Spiral Ganglion Neuron Apoptosis through Apoptosis Inducing Factor Pathway In Vitro

    PubMed Central

    Song, Yong-Li; Chen, Xiao-Dong; Mi, Wen-Juan; Wang, Jian; Lin, Ying; Chen, Fu-Quan; Qiu, Jian-Hua

    2015-01-01

    Objective This research aimed to investigate whether glutamate induced spiral ganglion neurons (SGNs) apoptosis through apoptosis inducing factor (AIF) pathway. And verify whether PD150606, a calpain inhibitor could prevent apoptosis by inhibiting cleaving and releasing AIF in mitochondrion. Methods SGNs of postnatal days 0-3 were harvested and cultured in dishes. 20 mM Glu, the caspase inhibitor Z-VAD-FMK and calpain inhibitor PD150606 were added into cultured dishes separately. We used optical microscope and immunofluoresence staining to observe cell morphology and AIF distribution, RT-PCR and Westernblot to analyse AIF and calpain expression in SGNs. TUNEL assay was used to test cell apoptosis. Results Cell morphology and nuclear translocation of AIF were altered in SGNs by 20 mM Glu treated in vitro. The axon of SGN shortened, more apoptosis SGN were observed and the expression of AIF and calpain were up-regulated in Glu-treated group than the normal one (P<0.05). The same experiments were conducted in 20 mM+PD150606 treated group and 20 mM+Z-VAD-FMK group. Obviously AIF were located from cytoplasm to the nuclear and the expressions of AIF and calpain were down-regulated by PD150606 (P<0.05). Positive cells in TUNEL staining decreased after PD150606 treating. However, Z-VAD-FMK had no influence on AIF, calpain expression or cell apoptosis. Conclusion The AIF-related apoptosis pathway is involved in the process of Glu-induced SGN injury. Furthermore, the inhibition of calpain can prevent AIF from releasing the nuclear or inducing SGN apoptosis. PMID:25874633

  6. Bromophenacyl bromide, a phospholipase A2 inhibitor attenuates chemically induced gastroduodenal ulcers in rats

    PubMed Central

    Tariq, Mohammad; Elfaki, Ibrahim; Khan, Haseeb Ahmad; Arshaduddin, Mohammad; Sobki, Samia; Moutaery, Meshal Al

    2006-01-01

    AIM: To study the effect of bromophenacyl bromide (BPB), a phospholipase A2 inhibitor on gastric secretion and to protect chemically induced gastric and duodenal ulcers in rats. METHODS: Acid secretion studies were undertaken in pylorus-ligated rats with BPB treatment (0, 5, 15 and 45 mg/kg). Gastric and duodenal lesions in the rats were induced by ethanol and cysteamine respectively. The levels of gastric wall mucus, nonprotein sulfhydryls (NP-SH) and myeloperoxidase (MPO) were also measured in the glandular stomach of rats following ethanol induced gastric lesions. RESULTS: BPB produced a dose-dependent inhibition of gastric acid secretion and acidity in rats. Pretreatment with BPB significantly attenuated the formation of ethanol induced gastric lesion. BPB also protected intestinal mucosa against cysteamine-induced duodenal ulcers. The antiulcer activity of BPB was associated with significant inhibition of ethanol-induced depletion of gastric wall mucus, NP-SH and MPO. These findings pointed towards the mediation of sulfhydryls in BPB induced gastrointestinal cytoprotection. CONCLUSION: BPB possesses significant antiulcer and cytoprotective activity against experimentally induced gastroduodenal lesions. PMID:17007045

  7. CTA095, a novel Etk and Src dual inhibitor, induces apoptosis in prostate cancer cells and overcomes resistance to Src inhibitors.

    PubMed

    Guo, Wenchang; Liu, Ruiwu; Bhardwaj, Gaurav; Ma, Ai-Hong; Changou, Chun; Yang, Joy C; Li, Yuanpei; Feng, Caihong; Luo, Yan; Mazloom, Anisha; Sanchez, Eduardo; Wang, Yan; Huang, Wenzhe; Patterson, Randen; Evans, Christopher P; Lam, Kit S; Kung, Hsing-Jien

    2013-01-01

    Etk is a non-receptor tyrosine kinase, which provides a strong survival signal in human prostate cancer cells. Src, another tyrosine kinase that cross-activates with Etk, has been shown to play an important role in prostate cancer metastasis. Herein, we discovered a new class of Etk inhibitors. Within those inhibitors, CTA095 was identified as a potent Etk and Src dual inhibitor. CTA095 was found to induce autophagy as well as apoptosis in human prostate cancer cells. In addition, CTA095 inhibited HUVEC cell tube formation and "wound healing" of human prostate cancer cells, implying its role in inhibition of angiogenesis and metastasis of human prostate cancer. More interestingly, CTA095 could overcome Src inhibitor resistance in prostate cancer cells. It induces apoptosis in Src inhibitor resistant prostate cancer cells, likely through a mechanism of down regulation of Myc and BCL2. This finding indicates that simultaneously targeting Etk and Src could be a promising approach to overcome drug resistance in prostate cancer. PMID:23967135

  8. Detrimental Effect of the Proteasome Inhibitor, Bortezomib in Bacterial Superantigen- and Lipopolysaccharide-induced Systemic Inflammation

    PubMed Central

    Tilahun, Ashenafi Y; Theuer, Jayne E; Patel, Robin; David, Chella S; Rajagopalan, Govindarajan

    2010-01-01

    Bacterial superantigen (BSAg)–induced toxic shock syndrome (TSS) and bacterial lipopolysaccharide (LPS)–induced shock are characterized by severe systemic inflammation. As nuclear factor κB (NFκB) plays an important role in inflammation and bortezomib, a proteasome inhibitor widely used in cancer chemotherapy, is a potent inhibitor of NFκB activation, we evaluated the therapeutic and prophylactic use of bortezomib in these conditions using murine models. Bortezomib prophylaxis significantly reduced serum levels of many cytokines and chemokines induced by BSAg. However, at 3 hours, serum level of TNF-a, an important cytokine implicated in TSS, was significantly reduced but not abolished. At 6 hours, there was no difference in the serum TNF-a levels between bortezomib treated and untreated mice challenged with staphylococcal enterotoxin B (SEB). Paradoxically, all mice treated with bortezomib either before or after BSAg challenge succumbed to TSS. Neither bortezomib nor BSAg was lethal if given alone. Serum biochemical parameters and histopathological findings suggested acute liver failure as the possible cause of mortality. Liver tissue from SEB-challenged mice treated with bortezomib showed a significant reduction in NFκB activation. Because NFκB-dependent antiapoptotic pathways protect hepatocytes from TNF-α-induced cell death, inhibition of NFκB brought forth by bortezomib in the face of elevated TNF-α levels caused by BSAg or LPS is detrimental. PMID:20372109

  9. Detrimental effect of the proteasome inhibitor, bortezomib in bacterial superantigen- and lipopolysaccharide-induced systemic inflammation.

    PubMed

    Tilahun, Ashenafi Y; Theuer, Jayne E; Patel, Robin; David, Chella S; Rajagopalan, Govindarajan

    2010-06-01

    Bacterial superantigen (BSAg)-induced toxic shock syndrome (TSS) and bacterial lipopolysaccharide (LPS)-induced shock are characterized by severe systemic inflammation. As nuclear factor kappaB (NF kappaB) plays an important role in inflammation and bortezomib, a proteasome inhibitor widely used in cancer chemotherapy, is a potent inhibitor of NF kappaB activation, we evaluated the therapeutic and prophylactic use of bortezomib in these conditions using murine models. Bortezomib prophylaxis significantly reduced serum levels of many cytokines and chemokines induced by BSAg. However, at 3 hours, serum level of TNF-a, an important cytokine implicated in TSS, was significantly reduced but not abolished. At 6 hours, there was no difference in the serum TNF-a levels between bortezomib treated and untreated mice challenged with staphylococcal enterotoxin B (SEB). Paradoxically, all mice treated with bortezomib either before or after BSAg challenge succumbed to TSS. Neither bortezomib nor BSAg was lethal if given alone. Serum biochemical parameters and histopathological findings suggested acute liver failure as the possible cause of mortality. Liver tissue from SEB-challenged mice treated with bortezomib showed a significant reduction in NF kappaB activation. Because NF kappaB-dependent antiapoptotic pathways protect hepatocytes from TNF-alpha-induced cell death, inhibition of NF kappaB brought forth by bortezomib in the face of elevated TNF-alpha levels caused by BSAg or LPS is detrimental. PMID:20372109

  10. Histone deacetylase inhibitors and transforming growth factor-beta induce 15-hydroxyprostaglandin dehydrogenase expression in human lung adenocarcinoma cells.

    PubMed

    Tong, Min; Ding, Yunfei; Tai, Hsin-Hsiung

    2006-09-14

    Histone deacetylase (HDAC) inhibitors have been actively exploited as potential anticancer agents. To identify gene targets of HDAC inhibitors, we found that HDAC inhibitors such as sodium butyrate, scriptaid, apicidin and oxamflatin induced the expression of 15-hydroxyprostaglandin dehydrogenase (15-PGDH), a potential cyclooxygenase-2 (COX-2) antagonist and tumor suppressor, in a time and concentration dependent manner in A549 and H1435 lung adenocarcinoma cells. Detailed analyses indicated that HDAC inhibitors activated the 15-PGDH promoter-luciferase reporter construct in transfected A549 cells. A representative HDAC inhibitor, scriptaid, and its negative structural analog control, nullscript, were further evaluated at the chromatin level. Scriptaid but not nullscript induced a significant accumulation of acetylated histones H3 and H4 which were associated with the 15-PGDH promoter as determined by chromatin immunoprecipitation assay. Transforming growth factor-beta1 (TGF-beta1) also induced the expression of 15-PGDH in a time and concentration dependent manner in A549 and H1435 cells. Induction of 15-PGDH expression by TGF-beta1 was synergistically stimulated by the addition of Wnt3A which was inactive by itself. However, combination of TGF-beta and an HDAC inhibitor, scriptaid, only resulted in an additive effect. Together, our results indicate that 15-PGDH is one of the target genes that HDAC inhibitors and TGF-beta may induce to exhibit tumor suppressive effects. PMID:16844092

  11. Hybrid inhibitor of peripheral cannabinoid-1 receptors and inducible nitric oxide synthase mitigates liver fibrosis

    PubMed Central

    Liu, Ziyi; Cao, Zongxian; Jourdan, Tony; Erdelyi, Katalin; Godlewski, Grzegorz; Szanda, Gergő; Liu, Jie; Park, Joshua K.; Mukhopadhyay, Bani; Rosenberg, Avi Z.; Liow, Jeih-San; Lorenz, Robin G.; Pacher, Pal; Innis, Robert B.; Kunos, George

    2016-01-01

    Liver fibrosis, a consequence of chronic liver injury and a way station to cirrhosis and hepatocellular carcinoma, lacks effective treatment. Endocannabinoids acting via cannabinoid-1 receptors (CB1R) induce profibrotic gene expression and promote pathologies that predispose to liver fibrosis. CB1R antagonists produce opposite effects, but their therapeutic development was halted due to neuropsychiatric side effects. Inducible nitric oxide synthase (iNOS) also promotes liver fibrosis and its underlying pathologies, but iNOS inhibitors tested to date showed limited therapeutic efficacy in inflammatory diseases. Here, we introduce a peripherally restricted, orally bioavailable CB1R antagonist, which accumulates in liver to release an iNOS inhibitory leaving group. In mouse models of fibrosis induced by CCl4 or bile duct ligation, the hybrid CB1R/iNOS antagonist surpassed the antifibrotic efficacy of the CB1R antagonist rimonabant or the iNOS inhibitor 1400W, without inducing anxiety-like behaviors or CB1R occupancy in the CNS. The hybrid inhibitor also targeted CB1R-independent, iNOS-mediated profibrotic pathways, including increased PDGF, Nlrp3/Asc3, and integrin αvβ6 signaling, as judged by its ability to inhibit these pathways in cnr1−/− but not in nos2−/− mice. Additionally, it was able to slow fibrosis progression and to attenuate established fibrosis. Thus, dual-target peripheral CB1R/iNOS antagonists have therapeutic potential in liver fibrosis. PMID:27525312

  12. Suppression of VEGF-induced angiogenesis by the protein tyrosine kinase inhibitor, lavendustin A.

    PubMed Central

    Hu, D E; Fan, T P

    1995-01-01

    1. Vascular endothelial growth factor (VEGF) is a heparin-binding angiogenic factor which specifically acts on endothelial cells via distinct membrane-spanning tyrosine kinase receptors. Here we used the rat sponge implant model to test the hypothesis that the angiogenic activity of VEGF can be suppressed by protein tyrosine kinase (PTK) inhibitors. 2. Neovascular responses in subcutaneous sponge implants were determined by measurements of relative sponge blood flow by use of a 133Xe clearance technique, and confirmed by histological studies and morphometric analysis. 3. Daily local administration of 250 ng VEGF165 accelerated the rate of 133Xe clearance from the sponges and induced an intense neovascularisation. This VEGF165-induced angiogenesis was inhibited by daily co-administration of the selective PTK inhibitor, lavendustin A (10 micrograms), but not its negative control, lavendustin B (10 micrograms). Blood flow measurements and morphometric analysis of 8-day-old sponges showed that lavendustin A reduced the 133Xe clearance of VEGF165-treated sponges from 32.9 +/- 1.5% to 20.9 +/- 1.6% and the total fibrovascular growth area from 62.4 +/- 6.1% to 21.6 +/- 6.8% (n = 12, P < 0.05). 4. Co-injection of suramin (3 mg), an inhibitor of heparin-binding growth factors, also suppressed the VEGF165-elicited neovascular response. In contrast, neither lavendustin A nor suramin produced any effect on the basal sponge-induced angiogenesis. 5. When given alone, low doses of VEGF165 (25 ng) or basic fibroblast growth factor (bFGF; 10 ng) did not modify the basal sponge-induced neovascularisation.(ABSTRACT TRUNCATED AT 250 WORDS) Images Figure 2 Figure 2 PMID:7533611

  13. Interferon-α and cyclooxygenase-2 inhibitor cooperatively mediates TRAIL-induced apoptosis in hepatocellular carcinoma

    SciTech Connect

    Zuo, Chaohui; Qiu, Xiaoxin; Liu, Nianli; Yang, Darong; Xia, Man; Liu, Jingshi; Wang, Xiaohong; and others

    2015-05-01

    Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide. Interferon-alpha (IFN-α) has recently been recognized to harbor therapeutic potential in the prevention and treatment of HCC, but it remains controversial as to whether IFN-α exerts direct cytotoxicity against HCC. Cyclooxygenase-2 (COX-2) is overexpressed in HCC and is considered to play a role in hepatocarcinogenesis. Therefore, we aimed to elucidate the combined effect of a COX-2 inhibitor, celecoxib, and IFN-α on in vitro growth suppression of HCC using the hepatoma cell line HLCZ01 and the in vivo nude mouse xenotransplantation model using HLCZ01 cells. Treatment with celecoxib and IFN-α synergistically inhibited cell proliferation in a dose- and time-dependent manner. Apoptosis was identified by 4',6-diamidino-2-phenylindole dihydrochloride and fluorescent staining. IFN-α upregulated the expression of TRAIL, while celecoxib increased the expression of TRAIL receptors. The combined regimen with celecoxib and IFN-α reduced the growth of xenotransplanted HCCs in nude mice. The regulation of IFN-α- and COX-2 inhibitor-induced cell death is impaired in a subset of TRAIL-resistant cells. The molecular mechanisms of HCC cells resistant to TRAIL-induced apoptosis were explored using molecular biological and immunological methods. Interferon-α and the COX-2 inhibitor celecoxib synergistically increased TRAIL-induced apoptosis in hepatocellular carcinoma. These data suggest that IFN-α and celecoxib may offer a novel role with important implications in designing new therapeutics for TRAIL-resistant tumors. - Highlights: ●The cytotoxic effect of TRAIL on a developed HCC HLCZ01 cells infected with HBV. ●IFN-α and celecoxib induced apoptosis in HLCZ01 cells infected with HBV. ●The combined regime reduced the growth of xenotransplanted HCCs in nude mice model.

  14. ACE inhibitors can induce circulating antibodies directed to antigens of the superficial epidermal cells.

    PubMed

    Cozzani, Emanuele; Rosa, Gian Marco; Drosera, Massimo; Intra, Chiara; Barsotti, Antonio; Parodi, Aurora

    2011-07-01

    Drug-induced pemphigus has been reported in patients receiving angiotensin-converting enzyme inhibitors. The aim of this work was to study a group of hypertensive patients without skin diseases treated with angiotensin-converting enzyme (ACE) Inhibitors (I), to verify the presence of serum circulating anti-antibodies. The indirect immunofluorescence showed that 33 sera (52.38%) presented autoantibodies directed to an antigen of the cytoplasm of the superficial epidermal keratinocytes. Two of the 33 positive sera had antibodies to Dsg1 and/or 3 in ELISA. Immunoblot analyses were negative. All the 48 control sera were found to have no circulating antibodies using the three assays. Our results would confirm that ACEI drugs may trigger the production of circulating autoantibodies also in patients without clinical manifestations of pemphigus. PMID:20563876

  15. Hypoxia inducible factor 1α expression and effects of its inhibitors in canine lymphoma

    PubMed Central

    KAMBAYASHI, Satoshi; IGASE, Masaya; KOBAYASHI, Kosuke; KIMURA, Ayana; SHIMOKAWA MIYAMA, Takako; BABA, Kenji; NOGUCHI, Shunsuke; MIZUNO, Takuya; OKUDA, Masaru

    2015-01-01

    Hypoxic conditions in various cancers are believed to relate with their malignancy, and hypoxia inducible factor-1α (HIF-1α) has been shown to be a major regulator of the response to low oxygen. In this study, we examined HIF-1α expression in canine lymphoma using cell lines and clinical samples and found that these cells expressed HIF-1α. Moreover, the HIF-1α inhibitors, echinomycin, YC-1 and 2-methoxyestradiol, suppressed the proliferation of canine lymphoma cell lines. In a xenograft model using NOD/scid mice, echinomycin treatment resulted in a dose-dependent regression of the tumor. Our results suggest that HIF-1α contributes to the proliferation and/or survival of canine lymphoma cells. Therefore, HIF-1α inhibitors may be potential agents to treat canine lymphoma. PMID:26050843

  16. Acute abdomen due to intestinal angioedema induced by ACE inhibitors: not so rare?

    PubMed

    Dobbels, P; Van Overbeke, L; Vanbeckevoort, D; Hiele, M

    2009-01-01

    During the last 5 years we identified 7 patients with a history of episodic acute abdominal pain and subobstruction due to intestinal angioedema secondary to the use of Angiotensin Converting Enzyme (ACE) inhibitors. These cases were all diagnosed in one gastroenterology department. This is thereby the largest single centre case series of ACE inhibitor-induced angioedema that has been published until now. Our findings suggest that this syndrome is far more frequent than international literature would let us believe. We also describe one of the first male cases diagnosed with this entity for which there is a significant female predominance. In the presence of an appropriate history and suggestive findings on CT scan, this diagnosis can relatively easily be made if one is sufficiently intent on it. An appropriate diagnosis can save these patients a lot of unnecessary diagnostic procedures and discomfort. PMID:20163043

  17. A dual inhibitor of cyclooxygenase and 5-lipoxygenase protects against kainic acid-induced brain injury.

    PubMed

    Minutoli, Letteria; Marini, Herbert; Rinaldi, Mariagrazia; Bitto, Alessandra; Irrera, Natasha; Pizzino, Gabriele; Pallio, Giovanni; Calò, Margherita; Adamo, Elena Bianca; Trichilo, Vincenzo; Interdonato, Monica; Galfo, Federica; Squadrito, Francesco; Altavilla, Domenica

    2015-06-01

    Systemic administration of kainic acid causes inflammation and apoptosis in the brain, resulting in neuronal loss. Dual cyclooxygenase/5-lipoxygenase (COX/5-LOX) inhibitors could represent a possible neuroprotective approach in preventing glutamate excitotoxicity. Consequently, we investigated the effects of a dual inhibitor of COX/5-LOX following intraperitoneal administration of kainic acid (KA, 10 mg/kg) in rats. Animals were randomized to receive either the dual inhibitor of COX/5-LOX (flavocoxid, 20 mg/kg i.p.) or its vehicle (1 ml/kg i.p.) 30 min after KA administration. Sham brain injury rats were used as controls. We evaluated protein expression of phosphorylated extracellular signal-regulated kinase (p-ERK1/2) and tumor necrosis factor alpha (TNF-α) as well as levels of malondialdehyde (MDA), prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) in the hippocampus. Animals were also observed for monitoring behavioral changes according to Racine Scale. Finally, histological analysis and brain edema evaluation were carried out. Treatment with the dual inhibitor of COX/5-LOX decreased protein expression of p-ERK1/2 and TNF-α in hippocampus, markedly reduced MDA, LTB4 and PGE2 hippocampal levels, and also ameliorated brain edema. Histological analysis showed a reduction in cell damage in rats treated with the dual inhibitor of COX/5-LOX, particularly in hippocampal subregion CA3c. Moreover, flavocoxid significantly improved behavioral signs following kainic acid administration. Our results suggest that dual inhibition of COX/5-LOX by flavocoxid has neuroprotective effects during kainic acid-induced excitotoxicity. PMID:25893744

  18. [Aromatase inhibitor letrozole induces sex inversion in the protogynous red spotted grouper (Epinephelus akaara).].

    PubMed

    Li, Guang-Li; Liu, Xiao-Chun; Lin, Hao-Ran

    2005-08-25

    The objective of this study was to investigate the effects of the aromatase inhibitor (AI) letrozole on gonadal development, serum steroids and aromatase activities in 2-year-old female red spotted grouper (Epinephelus akaara) during reproductive season. Groupers were divided into two groups, one implanted with aromatase inhibitor (AI, 5 mg/kg body weight) and the other elastomer without AI into peritoneal cavity once every four weeks for 8 weeks. Spermiation was checked through gentle abdominal pressure every 2 weeks. Blood samples were obtained from 6 fish of each group every 4 weeks for later analysis of sex steroids. After blood samples were collected, forebrain, midbrain, hindbrain, and gonads were collected and stored at -70 degrees C for later aromatase activity measurement and gonadal histological study. Significantly lower gondadosomatic index (GSI) was observed in AI-implanted group. Fish implanted with AI once showed complete degradation of oocytes and sex inversion with developing testicular tissues in the 4th week. AI induced females to develop into functional males with authentic males testes similar in structure to those in normal males. Spermiating rate of AI-treated males were 14.3%, 35.3%, and 48.4%in the 4th, 6th, and 8th week, respectively, while all fish in the control group were still female with developing ovaries. Aromatase activities in gonads decreased significantly after implantation with aromatase inhibitor, but showed no significant difference between control and AI-implanted group. No difference in serum testosterone (T) levels was observed in control and AI-treated group, while serum levels of 17beta-estradiol (E(2)) decreased but 11-ketotestosterone (11-KT) concentration increased significantly. The present results suggest that the decrease in serum 17beta-estradiol (E(2)) and increase in 11-KT levels may be important for sex inversion induced by aromatase inhibitor in red spotted grouper. PMID:16094495

  19. p53 modulates the AMPK inhibitor compound C induced apoptosis in human skin cancer cells

    SciTech Connect

    Huang, Shi-Wei; Wu, Chun-Ying; Wang, Yen-Ting; Kao, Jun-Kai; Lin, Chi-Chen; Chang, Chia-Che; Mu, Szu-Wei; Chen, Yu-Yu; Chiu, Husan-Wen; Chang, Chuan-Hsun; Liang, Shu-Mei; Chen, Yi-Ju; Huang, Jau-Ling; Shieh, Jeng-Jer

    2013-02-15

    Compound C, a well-known inhibitor of the intracellular energy sensor AMP-activated protein kinase (AMPK), has been reported to cause apoptotic cell death in myeloma, breast cancer cells and glioma cells. In this study, we have demonstrated that compound C not only induced autophagy in all tested skin cancer cell lines but also caused more apoptosis in p53 wildtype skin cancer cells than in p53-mutant skin cancer cells. Compound C can induce upregulation, phosphorylation and nuclear translocalization of the p53 protein and upregulate expression of p53 target genes in wildtype p53-expressing skin basal cell carcinoma (BCC) cells. The changes of p53 status were dependent on DNA damage which was caused by compound C induced reactive oxygen species (ROS) generation and associated with activated ataxia-telangiectasia mutated (ATM) protein. Using the wildtype p53-expressing BCC cells versus stable p53-knockdown BCC sublines, we present evidence that p53-knockdown cancer cells were much less sensitive to compound C treatment with significant G2/M cell cycle arrest and attenuated the compound C-induced apoptosis but not autophagy. The compound C induced G2/M arrest in p53-knockdown BCC cells was associated with the sustained inactive Tyr15 phosphor-Cdc2 expression. Overall, our results established that compound C-induced apoptosis in skin cancer cells was dependent on the cell's p53 status. - Highlights: ► Compound C caused more apoptosis in p53 wildtype than p53-mutant skin cancer cells. ► Compound C can upregulate p53 expression and induce p53 activation. ► Compound C induced p53 effects were dependent on ROS induced DNA damage pathway. ► p53-knockdown attenuated compound C-induced apoptosis but not autophagy. ► Compound C-induced apoptosis in skin cancer cells was dependent on p53 status.

  20. Angiotensin II induces secretion of plasminogen activator inhibitor 1 and a tissue metalloprotease inhibitor-related protein from rat brain astrocytes

    SciTech Connect

    Olson, J.A. Jr.; Shiverick, K.T.; Ogilvie, S.; Buhi, W.C.; Raizada, M.K. )

    1991-03-01

    The present study investigates angiotensin (Ang) II effects on secretory protein synthesis in brain astrocytes cultured from neonatal and 21-day-old rats. Ang II-induced changes in the de novo synthesis of (35S)methionine-labeled secretory proteins were visualized using two-dimensional NaDodSO4/PAGE. Astrocytes from 21-day-old rat brain possess specific high-affinity receptors for Ang II. These cells express two Ang II-induced secretory proteins with Mr 55,000 (AISP-55K) and Mr 30,000 (AISP-30K), which were time- and dose-dependent (EC50, 1 nM). (Sar1, Ile8)Ang II (where Sar is sarcosine) inhibited Ang II-induced secretion of AISP-55K but not AISP-30K. N-terminal amino acid sequencing indicates that AISP-55K is identical to rat plasminogen activator inhibitor 1, whereas AISP-30K exhibits 72-81% identity to three closely related proteins: human tissue inhibitor of metalloproteases, a rat phorbol ester-induced protein, and the murine growth-responsive protein 16C8. Immunofluorescent staining with rat plasminogen activator inhibitor 1 antibody was induced in the majority of cells in culture after Ang II treatment of astrocytes from 21-day-old rat brains. Absence of this response to Ang II in astrocytes from neonatal rat brain provides evidence that this action of Ang II on astrocytes is developmentally regulated.

  1. Inhibitors of adriamycin-induced histamine release in vitro limit adriamycin cardiotoxicity in vivo.

    PubMed Central

    Klugmann, F. B.; Decorti, G.; Candussio, L.; Grill, V.; Mallardi, F.; Baldini, L.

    1986-01-01

    The activity of theophylline and disodium cromoglycate was tested on adriamycin-induced histamine release in vitro and on adriamycin cardiotoxicity in vivo. Both substances significantly inhibited the release of histamine induced by 100 micrograms ml-1 of adriamycin on rat peritoneal cells and produced significant protection against adriamycin-mediated acute and chronic cardiotoxicity in mice. N-acetylcysteine, a free radical scavenger, successfully used in the prevention of the cardiomyopathy, was also found to be an inhibitor of histamine release induced by adriamycin and compound 48/80 on rat peritoneal cells. This study further supports the hypothesis that the release of histamine may be involved in the pathogenesis of anthracycline cardiotoxicity. Images Figure 5 Figure 6 Figure 7 Figure 8 PMID:2432914

  2. Nonhypoxic regulation and role of hypoxia-inducible factor 1 in aromatase inhibitor resistant breast cancer

    PubMed Central

    2014-01-01

    Introduction Although aromatase inhibitors (AIs; for example, letrozole) are highly effective in treating estrogen receptor positive (ER+) breast cancer, a significant percentage of patients either do not respond to AIs or become resistant to them. Previous studies suggest that acquired resistance to AIs involves a switch from dependence on ER signaling to dependence on growth factor-mediated pathways, such as human epidermal growth factor receptor-2 (HER2). However, the role of HER2, and the identity of other relevant factors that may be used as biomarkers or therapeutic targets remain unknown. This study investigated the potential role of transcription factor hypoxia inducible factor 1 (HIF-1) in acquired AI resistance, and its regulation by HER2. Methods In vitro studies using AI (letrozole or exemestane)-resistant and AI-sensitive cells were conducted to investigate the regulation and role of HIF-1 in AI resistance. Western blot and RT-PCR analyses were conducted to compare protein and mRNA expression, respectively, of ERα, HER2, and HIF-1α (inducible HIF-1 subunit) in AI-resistant versus AI-sensitive cells. Similar expression analyses were also done, along with chromatin immunoprecipitation (ChIP), to identify previously known HIF-1 target genes, such as breast cancer resistance protein (BCRP), that may also play a role in AI resistance. Letrozole-resistant cells were treated with inhibitors to HER2, kinase pathways, and ERα to elucidate the regulation of HIF-1 and BCRP. Lastly, cells were treated with inhibitors or inducers of HIF-1α to determine its importance. Results Basal HIF-1α protein and BCRP mRNA and protein are higher in AI-resistant and HER2-transfected cells than in AI-sensitive, HER2- parental cells under nonhypoxic conditions. HIF-1α expression in AI-resistant cells is likely regulated by HER2 activated-phosphatidylinositide-3-kinase/Akt-protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway, as its expression was inhibited

  3. Acquisition and reinstatement of ethanol-induced conditioned place preference in rats: Effects of the cholinesterase inhibitors donepezil and rivastigmine.

    PubMed

    Gawel, Kinga; Labuz, Krzysztof; Gibula-Bruzda, Ewa; Jenda, Malgorzata; Marszalek-Grabska, Marta; Silberring, Jerzy; Kotlinska, Jolanta H

    2016-07-01

    The present study examined the influence of the cholinesterase inhibitors donepezil (a selective inhibitor of acetylcholinesterase) and rivastigmine (also an inhibitor of butyrylcholinesterase) on the acquisition and reinstatement of ethanol-induced conditioned place preference (CPP) in rats. Before the CPP procedure, animals received a single injection of ethanol (0.5 g/kg, 10% w/v, intraperitoneally [i.p.]) for 15 days. The ethanol-induced CPP (biased method) was developed by four injections of ethanol (0.5 g/kg, 10% w/v, i.p.) every second day. Control rats received saline instead of ethanol. Donepezil (0.5, 1 or 3 mg/kg, i.p.) or rivastigmine (0.03, 0.5 or 1 mg/kg, i.p.) were administered before ethanol during conditioning or before the reinstatement of ethanol-induced CPP. The cholinesterase inhibitors were equally effective in increasing (dose dependently) the acquisition of ethanol-induced CPP. Furthermore, priming injections of both inhibitors reinstated (cross-reinstatement) the ethanol-induced CPP with similar efficacy. These effects of both cholinesterase inhibitors were reversed by mecamylamine (3 mg/kg, i.p.), a nicotinic acetylcholine receptor antagonist, but not by scopolamine (0.5 mg/kg, i.p.), a muscarinic acetylcholine receptor antagonist. Thus, our results show that the cholinergic system is involved in the reinforcing properties of ethanol, and nicotinic acetylcholine receptors play an important role in the relapse to ethanol-seeking behaviour. PMID:27097732

  4. Effects of addition of a dipeptidyl peptidase IV inhibitor to metformin on sirolimus-induced diabetes mellitus.

    PubMed

    Jin, Long; Lim, Sun Woo; Jin, Jian; Chung, Byung Ha; Yang, Chul Woo

    2016-08-01

    The guideline for the management of new-onset diabetes after transplantation recommends metformin (MET) as a first-line drug, and addition of a second-line drug is needed to better control of hyperglycemia. We tested the effect of addition of a dipeptidyl peptidase IV (DPP IV) inhibitor to MET on sirolimus (SRL)-induced diabetes mellitus (DM). In animal model of SRL-induced DM, MET treatment improved pancreatic islet function (blood glucose level and insulin secretion) and attenuated oxidative stress and apoptotic cell death. Addition of a DPP IV inhibitor to MET improved these parameters more than MET alone. An in vitro study showed that SRL treatment increased pancreas beta cell death and production of reactive oxygen species (ROS), and pretreatment of ROS inhibitor, or p38MAPK inhibitor effectively decreased SRL-induced islet cell death. Exendin-4 (EXD), a substrate of DPP IV or MET significantly improved cell viability and decreased ROS production compared with SRL treatment, and combined treatment with the 2 drugs improved both parameters. At the subcellular level, impaired mitochondrial respiration by SRL were partially improved by MET or EXD and much improved further after addition of EXD to MET. Our data suggest that addition of a DPP IV inhibitor to MET decreases SRL-induced oxidative stress and improves mitochondrial respiration. This finding provides a rationale for the combined use of a DPP IV inhibitor and MET in treating SRL-induced DM. PMID:27059001

  5. Sorafenib treatment in children with relapsed and refractory neuroblastoma: an experience of four cases.

    PubMed

    Okada, Keiko; Nakano, Yoshiko; Yamasaki, Kai; Nitani, Chika; Fujisaki, Hiroyuki; Hara, Junichi

    2016-08-01

    Metastatic neuroblastoma is an aggressive malignancy with a poor prognosis. Recent findings have shown that sorafenib decreases cell viability and increases apoptosis in human neuroblastoma cell lines. We report an experience of compassionate use of sorafenib in children with treatment-refractory neuroblastoma. Sorafenib showed transient anti-tumor activity in all four patients without adverse effects. However, progression was observed after a short stabilization phase. While sorafenib showed minimal anti-tumor activity in our patients, it might still be effective in patients with neuroblastoma in an earlier stage. PMID:27264843

  6. Efficacy of combination treatment modalities for intermediate and advanced hepatocellular carcinoma: intra-arterial therapies, sorafenib and novel small molecules

    PubMed Central

    Gutierrez, Julio A.; Gish, Robert G.

    2015-01-01

    Hepatocellular carcinoma (HCC) is a growing epidemic with a high mortality rate and clear need for improved therapies. In patients with Barcelona-Clinic Liver Cancer (BCLC) B and C, treatment with transarterial chemoembolization (TACE) has been the gold standard in therapy as it delays progression; however, recurrence proves common. In the US, transarterial bead embolization (TABE) has uniformly replaced TACE. With this limited armamentarium, there is need for a shift to novel strategies combining different modalities to further improve patient outcomes. Historically, HCC drug discovery concentrated on common features of HCC including its highly vascular nature and dependence on growth factors (GFs). The multikinase inhibitor sorafenib acts on angiogenesis via modulation of vascular endothelial GF expression and was the first step toward systemic targeted therapy against HCC. Sorafenib has provided clinicians with a tool to modestly improve survival by 2–6 months or longer. Despite the progress in survival provided by TACE, TABE and sorafenib independently, rigorous combination clinical trials do not consistently show significant improvement over TACE/TABE monotherapy. Other novel small molecules targeting angiogenesis such as brivanib, linifanib and everolimus have failed or are in development. Anti-HCV treatment became more feasible with the novel direct-acting antiviral agents; with the much higher and more durable treatment responses that they provide, the risk of HCC progression may be reduced. The most effective strategies in developing combination therapies are hampered by the complexities of FDA testing along with intellectual property and economic issues. To achieve significant progress, more basic science studies are necessary to help understand which novel molecules demonstrate the greatest synergy. Individual patient genomic profiling and biomarkers may help guide therapy and improve the clinician’s ability to tailor treatment and to know when it

  7. Phase II Trial of Sorafenib in Patients with Chemotherapy Refractory Metastatic Esophageal and Gastroesophageal (GE) Junction Cancer

    PubMed Central

    Janjigian, Yelena Y.; Vakiani, Efsevia; Ku, Geoffrey Y.; Herrera, Jessica M.; Tang, Laura H.; Bouvier, Nancy; Viale, Agnès; Socci, Nicholas D.; Capanu, Marinela; Berger, Michael; Ilson, David H.

    2015-01-01

    Purpose Vascular endothelial growth factor receptor (VEGFR2) directed therapies result in a modest survival benefit for patients with advanced esophageal and gastroesophageal (GE) junction cancer. Platelet-derived growth factor receptor (PDGFR) may contribute to escape from VEGFR2 inhibition. We evaluated the efficacy of sorafenib, a broad spectrum tyrosine kinase inhibitor targeting VEGFR2 and PDGFR as well as RET and RAF1, in patients with metastatic chemotherapy refractory esophageal and GE junction cancer. Patients and Methods This phase II trial of sorafenib 400 mg twice daily enrolled chemotherapy refractory patients with metastatic esophageal and GE junction cancer with primary endpoint of progression-free survival (PFS) rate at two months. Secondary endpoints included overall survival, objective response rate and toxicity. Results Among 34 patients, 8 week Kaplan-Meier estimated PFS was 61% (90%CI 45 to 73%). Median PFS is 3.6 months (95% CI 1.8 to 3.9 months), with median overall survival OS 9.7 months (95% CI 5.9 to 11.6 months). Grade 3 toxicities were uncommon and included hand foot skin reaction, rash, dehydration and fatigue. One patient (3%) with ongoing complete response and remains on trial for over 5 years. Whole exome sequencing of this tumor revealed mutations in many cancer-associated genes including ARID1A, PIK3CA, and TP53, and focal amplifications of HMGA2 and MET. Conclusion Sorafenib therapy results in disease stabilization and encouraging PFS in patients with refractory esophageal and GE junction cancer. Trial Registration ClinicalTrials.gov NCT00917462 PMID:26275293

  8. AKT inhibitor suppresses hyperthermia-induced Ndrg2 phosphorylation in gastric cancer cells

    PubMed Central

    Tao, Yurong; Guo, Yan; Liu, Wenchao; Zhang, Jian; Li, Xia; Shen, Lan; Ru, Yi; Xue, Yan; Zheng, Jin; Liu, Xinping; Zhang, Jing; Yao, Libo

    2013-01-01

    Hyperthermia is one of the most effective adjuvant treatments for various cancers with few side effects. However, the underlying molecular mechanisms still are not known. N-myc downstream-regulated gene 2 (NDRG2), a tumor suppressor, has been shown to be involved in diverse cellular stresses including hypoxia, lipotoxicity, etc. In addition, Ndrg2 has been reported to be related to progression of gastric cancer. In the current study, our data showed that the apoptosis rate of MKN28 cells increased relatively rapidly to 13.4% by 24 h after treatment with hyperthermia (42°C for 1 h) compared to 5.1% in control cells (P < 0.05). Nevertheless, there was no obvious change in the expression level of total Ndrg2 during this process. Further investigation demonstrated that the relative phosphorylation levels of Ndrg2 at Ser332, Thr348 increased up to 3.2- and 1.9-fold (hyperthermia group vs control group) at 3 h in MKN28 cells, respectively (P < 0.05). We also found that heat treatment significantly increased AKT phosphorylation. AKT inhibitor VIII (10 µM) decreased the phosphorylation level of Ndrg2 induced by hyperthermia. Accordingly, the apoptosis rate rose significantly in MKN28 cells (16.4%) treated with a combination of AKT inhibitor VIII and hyperthermia compared to that (6.8%) of cells treated with hyperthermia alone (P < 0.05). Taken together, these data demonstrated that Ndrg2 phosphorylation could be induced by hyperthermia in an AKT-dependent manner in gastric cancer cells. Furthermore, AKT inhibitor VIII suppressed Ndrg2 phosphorylation and rendered gastric cancer cells susceptible to apoptosis induced by hyperthermia. PMID:23558861

  9. HDAC inhibitors induce epithelial-mesenchymal transition in colon carcinoma cells.

    PubMed

    Ji, Meiying; Lee, Eun Jeoung; Kim, Ki Bae; Kim, Yangmi; Sung, Rohyun; Lee, Sang-Jeon; Kim, Don Soo; Park, Seon Mee

    2015-05-01

    The effects of histone deacetylase (HDAC) inhibitors on epithelial-mesenchymal transition (EMT) differ in various types of cancers. We investigated the EMT phenotype in four colon cancer cell lines when challenged with HDAC inhibitors trichostatin A (TSA) and valproic acid (VPA) with or without transforming growth factor-β1 (TGF-β1) treatment. Four colon cancer cell lines with different phenotypes in regards to tumorigenicity, microsatellite stability and DNA mutation were used. EMT phenotypes were assessed by the expression of E-cadherin and vimentin using western blot analysis, immunofluorescence, quantitative real-time RT-PCR following treatment with TSA (100 or 200 nM) or VPA (0.5 mM) with or without TGF-β1 (5 ng/ml) for 24 h. Biological EMT phenotypes were also evaluated by cell morphology, migration and invasion assays. TSA or VPA induced mesenchymal features in the colon carcinoma cells by a decrease in E-cadherin and an increase in vimentin expression at the mRNA and protein levels. Confocal microscopy revealed membranous attenuation or nuclear translocation of E-cadherin and enhanced expression of vimentin. These responses occurred after 6 h and increased until 24 h. Colon cancer cells changed from a round or rectangular shape to a spindle shape with increased migration and invasion ability following TSA or VPA treatment. The susceptibility to EMT changes induced by TSA or VPA was comparable in microsatellite stable (SW480 and HT29) and microsatellite unstable cells (DLD1 and HCT116). TSA or VPA induced a mesenchymal phenotype in the colon carcinoma cells and these effects were augmented in the presence of TGF-β1. HDAC inhibitors require careful caution before their application as new anticancer drugs for colon cancers. PMID:25813246

  10. Cholinesterase inhibitors ameliorate behavioral deficits induced by MK-801 in mice.

    PubMed

    Csernansky, John G; Martin, Maureen; Shah, Renu; Bertchume, Amy; Colvin, Jenny; Dong, Hongxin

    2005-12-01

    Enhancing cholinergic function has been suggested as a possible strategy for ameliorating the cognitive deficits of schizophrenia. The purpose of this study was to examine the effects of acetylcholinesterase (AChE) inhibitors in mice treated with the noncompetitive N-methyl-d-aspartate (NMDA) receptor antagonist, MK-801, which has been suggested as an animal model of the cognitive deficits of schizophrenia. Three separate experiments were conducted to test the effects of physostigmine, donepezil, or galantamine on deficits in learning and memory induced by MK-801. In each experiment, MK-801 (0.05 or 0.10 mg/kg) or saline was administered i.p. 20 min prior to behavioral testing over a total of 12 days. At 30 min prior to administration of MK-801 or saline, one of three doses of the AChE inhibitor (ie physostigmine-0.03, 0.10, or 0.30 mg/kg; donepezil-0.10, 0.30, or 1.00 mg/kg; or galantamine-0.25, 0.50, or 1.00 mg/kg) or saline was administered s.c. Behavioral testing was performed in all experimental animals using the following sequence: (1) spatial reversal learning, (2) locomotion, (3) fear conditioning, and (4) shock sensitivity. Both doses of MK-801 produced impairments in spatial reversal learning and in contextual and cued memory, as well as hyperlocomotion. Physostigmine and donepezil, but not galantamine, ameliorated MK-801-induced deficits in spatial reversal learning and in contextual and cued memory in a dose-dependent manner. Also, physostigmine, but not donepezil or galantamine, reversed MK-801-induced hyperlocomotion. Galantamine, but not physostigmine or donepezil, altered shock sensitivity. These results suggest that AChE inhibitors may differ in their capacity to ameliorate learning and memory deficits produced by MK-801 in mice, which may have relevance for the cognitive effects of cholinomimetic drugs in patients with schizophrenia. PMID:15956997

  11. SELECTIVE AND NON-SELECTIVE METALLOPROTEINASE INHIBITORS REDUCE IL-1-INDUCED CARTILAGE DEGRADATION AND LOSS OF MECHANICAL PROPERTIES

    PubMed Central

    Wilson, Christopher G.; Palmer, Ashley W.; Zuo, Fengrong; Eugui, Elsie; Wilson, Stacy; Mackenzie, Rebecca; Sandy, John D.; Levenston, Marc E.

    2015-01-01

    Articular cartilage undergoes matrix degradation and loss of mechanical properties when stimulated with proinflammatory cytokines such as interleukin-1 (IL-1). Aggrecanases and matrix metalloproteinases (MMPs) are thought to be principal downstream effectors of cytokine-induced matrix catabolism, and aggrecanase- or MMP-selective inhibitors reduce or block matrix destruction in several model systems. The objective of this study was to use metalloproteinase inhibitors to perturb IL-1-induced matrix catabolism in bovine cartilage explants and examine their effects on changes in tissue compression and shear properties. Explanted tissue was stimulated with IL-1 for up to 24 days in the absence or presence of inhibitors which were aggrecanase-selective, MMP-selective, or non-selective. Analysis of conditioned media and explant digests revealed that aggrecanase-mediated aggrecanolysis was delayed to varying extents with all inhibitor treatments, but that aggrecan release persisted. Collagen degradation was abrogated by MMP- and non-selective inhibitors and reduced by the aggrecanase inhibitor. The inhibitors delayed but did not reduce loss of the equilibrium compression modulus, whereas the loss of dynamic compression and shear moduli was delayed and reduced. The data suggest that non-metalloproteinase mechanisms participate in IL-1-induced matrix degradation and loss of tissue material properties. PMID:17174540

  12. The gene coding for the mustard trypsin inhibitor-2 is discontinuous and wound-inducible.

    PubMed

    Ceci, L R; Spoto, N; de Virgilio, M; Gallerani, R

    1995-05-01

    The gene coding for the mustard trypsin inhibitor-2 has been isolated from a genomic library and characterized. Comparison of genomic and cDNA sequences indicates that the gene is interrupted by an intron of 193 bp. The eukaryotic peculiar regulatory sequences have been detected in the 5' flanking region of the gene. In addition, a decanucleotide has been detected that is highly similar to the proposed G-box and to the ABRE motifs required for the gene expression induced by methyl jasmonate and abscissic acid. Northern blot analysis demonstrates that the gene is expressed in immature seeds as well as in wounded leaves. PMID:7750566

  13. Effects of lipoxygenase inhibitors in a model of lens-induced uveitis in dogs.

    PubMed

    Dziezyc, J; Millichamp, N J; Rohde, B H; Baker, J S; Chiou, G C

    1989-11-01

    Uveitis was induced in dogs by intracameral injection of canine lens protein. The lipoxygenase inhibitors phenidone and norhydroguaiaretic acid, and dimethyl sulfoxide decreased fibrin production at 0.5 and 1 hour after induction of uveitis. Phenidone and norhydroguaiaretic acid also inhibited the initial increase in intraocular pressure early in the course of inflammation. Leukotriene B4 in the aqueous was measured by use of radioimmunoassay at 1 hour after inflammation. In control dogs, 230 to 1,700 pg of leukotriene B4/ml was measured; in dogs treated with phenidone, leukotriene B4 was not measured. PMID:2515781

  14. Heat shock protein inhibitors, 17-DMAG and KNK437, enhance arsenic trioxide-induced mitotic apoptosis

    SciTech Connect

    Wu Yichen; Yen Wenyen; Lee, T.-C. Yih, L.-H.

    2009-04-15

    Arsenic trioxide (ATO) has recently emerged as a promising therapeutic agent in leukemia because of its ability to induce apoptosis. However, there is no sufficient evidence to support its therapeutic use for other types of cancers. In this study, we investigated if, and how, 17-dimethylaminoethylamino-17-demethoxy-geldanamycin (17-DMAG), an antagonist of heat shock protein 90 (HSP90), and KNK437, a HSP synthesis inhibitor, potentiated the cytotoxic effect of ATO. Our results showed that cotreatment with ATO and either 17-DMAG or KNK437 significantly increased ATO-induced cell death and apoptosis. siRNA-mediated attenuation of the expression of the inducible isoform of HSP70 (HSP70i) or HSP90{alpha}/{beta} also enhanced ATO-induced apoptosis. In addition, cotreatment with ATO and 17-DMAG or KNK437 significantly increased ATO-induced mitotic arrest and ATO-induced BUBR1 phosphorylation and PDS1 accumulation. Cotreatment also significantly increased the percentage of mitotic cells with abnormal mitotic spindles and promoted metaphase arrest as compared to ATO treatment alone. These results indicated that 17-DMAG or KNK437 may enhance ATO cytotoxicity by potentiating mitotic arrest and mitotic apoptosis possibly through increased activation of the spindle checkpoint.

  15. mTOR inhibitors counteract tamoxifen-induced activation of breast cancer stem cells.

    PubMed

    Karthik, Govindasamy-Muralidharan; Ma, Ran; Lövrot, John; Kis, Lorand Levente; Lindh, Claes; Blomquist, Lennart; Fredriksson, Irma; Bergh, Jonas; Hartman, Johan

    2015-10-10

    Breast cancer cells with stem cell characteristics (CSC) are a distinct cell population with phenotypic similarities to mammary stem cells. CSCs are important drivers of tumorigenesis and the metastatic process. Tamoxifen is the most widely used hormonal therapy for estrogen receptor (ER) positive cancers. In our study, tamoxifen was effective in reducing proliferation of ER + adherent cancer cells, but not their CSC population. We isolated, expanded and incubated CSC from seven breast cancers with or without tamoxifen. By genome-wide transcriptional analysis we identified tamoxifen-induced transcriptional pathways associated with ribosomal biogenesis and mRNA translation, both regulated by the mTOR-pathway. We observed induction of the key mTOR downstream targets S6K1, S6RP and 4E-BP1 in-patient derived CSCs by tamoxifen on protein level. Using the mTOR inhibitors rapamycin, everolimus and PF-04691502 (a dual PI3K/mTOR inhibitor) and in combination with tamoxifen, significant reduction in mammosphere formation was observed. Hence, we suggest that the CSC population play a significant role during endocrine resistance through activity of the mTOR pathway. In addition, tamoxifen further stimulates the mTOR-pathway but can be antagonized using mTOR-inhibitors. PMID:26208432

  16. Saxagliptin: a dipeptidyl peptidase-4 inhibitor ameliorates streptozotocin induced Alzheimer's disease.

    PubMed

    Kosaraju, Jayasankar; Gali, Chaitanya Chakravarthi; Khatwal, Rizwan Basha; Dubala, Anil; Chinni, Santhivardhan; Holsinger, R M Damian; Madhunapantula, V Subba Rao; Muthureddy Nataraj, Satish Kumar; Basavan, Duraiswamy

    2013-09-01

    Type 2 diabetes (T2D) is one of the major risk factors associated with Alzheimer's disease (AD). Recent studies have found similarities in molecular mechanisms that underlie the respective degenerative developments in the two diseases. Pharmacological agents, such as dipeptidyl peptidase-4 (DPP-4) inhibitors, which increase the level of glucagon-like peptide-1 (GLP-1) and ameliorate T2D, have become valuable candidates as disease modifying agents in the treatment of AD. In addition, endogenous GLP-1 levels decrease amyloid beta (Aβ) peptide and tau phosphorylation in AD. The present study examines the efficacy of Saxagliptin, a DPP-4 inhibitor in a streptozotocin (STZ) induced rat model of AD. Three months following induction of AD by intracerebral administration of streptozotocin, animals were orally administered Saxagliptin (0.25, 0.5 and 1 mg/kg) for 60 days. The effect of the DPP-4 inhibitor on hippocampal GLP-1 levels, Aβ burden, tau phosphorylation, inflammatory markers and memory retention were evaluated. The results reveal an attenuation of Aβ, tau phosphorylation and inflammatory markers and an improvement in hippocampal GLP-1 and memory retention following treatment. This remarkable therapeutic effect of Saxagliptin mediated through DPP-4 inhibition demonstrates a unique mechanism for Aβ and tau clearance by increasing GLP-1 levels and reverses the behavioural deficits and pathology observed in AD. PMID:23603201

  17. A Novel Malate Dehydrogenase 2 Inhibitor Suppresses Hypoxia-Inducible Factor-1 by Regulating Mitochondrial Respiration.

    PubMed

    Ban, Hyun Seung; Xu, Xuezhen; Jang, Kusik; Kim, Inhyub; Kim, Bo-Kyung; Lee, Kyeong; Won, Misun

    2016-01-01

    We previously reported that hypoxia-inducible factor (HIF)-1 inhibitor LW6, an aryloxyacetylamino benzoic acid derivative, inhibits malate dehydrogenase 2 (MDH2) activity during the mitochondrial tricarboxylic acid (TCA) cycle. In this study, we present a novel MDH2 inhibitor compound 7 containing benzohydrazide moiety, which was identified through structure-based virtual screening of chemical library. Similar to LW6, compound 7 inhibited MDH2 activity in a competitive fashion, thereby reducing NADH level. Consequently, compound 7 reduced oxygen consumption and ATP production during the mitochondrial respiration cycle, resulting in increased intracellular oxygen concentration. Therefore, compound 7 suppressed the accumulation of HIF-1α and expression of its target genes, vascular endothelial growth factor (VEGF) and glucose transporter 1 (GLUT1). Moreover, reduction in ATP content activated AMPK, thereby inactivating ACC and mTOR the downstream pathways. As expected, compound 7 exhibited significant growth inhibition of human colorectal cancer HCT116 cells. Compound 7 demonstrated substantial anti-tumor efficacy in an in vivo xenograft assay using HCT116 mouse model. Taken together, a novel MDH2 inhibitor, compound 7, suppressed HIF-1α accumulation via reduction of oxygen consumption and ATP production, integrating metabolism into anti-cancer efficacy in cancer cells. PMID:27611801

  18. Changes of epidermal cell morphology and keratin expression induced by inhibitors of protein kinase C.

    PubMed

    Hegemann, L; Wevers, A; Bonnekoh, B; Mahrle, G

    1992-03-01

    Several lines of evidence show protein kinase C as being involved in various regulatory processes in keratinocyte biology, e.g. proliferation and differentiation. In the present study, we investigated the effects of three different inhibitors of protein kinase C, staurosporine, CP 46'665-1, and tiflucarbine, on cell morphology and keratin expression in a non-tumorigenic human keratinocyte cell line (HaCaT cells). Staurosporine, being the most potent inhibitor of protein kinase C activity in vitro, and CP 46'665-1 induced morphological transformation to a fibroblast-like cell shape. In contrast, no changes in cell morphology were observed after exposure to tiflucarbine. The investigation of keratin expression in HaCaT cells grown in the presence of the different compounds revealed the following changes: After 72 h of cultivation, keratins 8 and 18 were still expressed in treated cells, whereas expression of keratin 13 was decreased as compared to control cells. Immunoblotting to detect vimentin demonstrated its absence in treated and control cells. Since tiflucarbine is known as a dual protein kinase C/calmodulin inhibitor whereas staurosporine and CP 46'665-1 do not antagonize calmodulin function, it might be possible that not only protein kinase C but also calmodulin is involved in the process leading to the morphological changes. PMID:1376142

  19. Anti-Ulcer Efficacy of Soluble Epoxide Hydrolase Inhibitor TPPU on Diclofenac-Induced Intestinal Ulcers

    PubMed Central

    Goswami, Sumanta Kumar; Wan, Debin; Yang, Jun; Trindade da Silva, Carlos A.; Morisseau, Christophe; Kodani, Sean D.; Yang, Guang-Yu; Inceoglu, Bora

    2016-01-01

    Proton pump inhibitors such as omeprazole (OME) reduce the severity of gastrointestinal (GI) ulcers induced by nonsteroidal anti-inflammatory drugs (NSAIDs) but can also increase the chance of dysbiosis. The aim of this study was to test the hypothesis that preventive use of a soluble epoxide hydrolase inhibitor (sEHI) such as TPPU can decrease NSAID-induced ulcers by increasing anti-inflammatory epoxyeicosatrienoic acids (EETs). Dose- [10, 30, and 100 mg/kg, by mouth (PO)] and time-dependent (6 and 18 hours) ulcerative effects of diclofenac sodium (DCF, an NSAID) were studied in the small intestine of Swiss Webster mice. Dose-dependent effects of TPPU (0.001–0.1 mg/kg per day for 7 days, in drinking water) were evaluated in DCF-induced intestinal toxicity and compared with OME (20 mg/kg, PO). In addition, the effect of treatment was studied on levels of Hb in blood, EETs in plasma, inflammatory markers such as myeloperoxidase (MPO) in intestinal tissue homogenates, and tissue necrosis factor-α (TNF-α) in serum. DCF dose dependently induced ulcers that were associated with both a significant (P < 0.05) loss of Hb and an increase in the level of MPO and TNF-α, with severity of ulceration highest at 18 hours. Pretreatment with TPPU dose dependently prevented ulcer formation by DCF, increased the levels of epoxy fatty acids, including EETs, and TPPU’s efficacy was comparable to OME. TPPU significantly (P < 0.05) reversed the effect of DCF on the level of Hb, MPO, and TNF-α. Thus sEHI might be useful in the management of NSAID-induced ulcers. PMID:26989141

  20. Effect of the 5-lipoxygenase inhibitor ZD2138 on aspirin-induced asthma.

    PubMed Central

    Nasser, S. M.; Bell, G. S.; Foster, S.; Spruce, K. E.; MacMillan, R.; Williams, A. J.; Lee, T. H.; Arm, J. P.

    1994-01-01

    BACKGROUND--The cysteinyl leukotrienes may play a central part in the mechanisms of aspirin-sensitive asthma. Previous work has shown that individuals with aspirin-sensitive asthma have high basal urinary LTE4 levels which increase further upon aspirin ingestion, and that sulphidopeptide leukotriene receptor antagonists attenuate aspirin-induced airflow obstruction. If the cysteinyl leukotrienes cause aspirin-induced asthmatic reactions, inhibition of the 5-lipoxygenase pathway should prevent aspirin-induced bronchospasm. This hypothesis has been tested with ZD2138, a specific non-redox 5-lipoxygenase inhibitor. METHODS--Seven subjects (four men) with aspirin-sensitive asthma with baseline FEV1 values > 67% were studied. ZD2138 (350 mg) or placebo was given on two separate occasions two weeks apart in a randomised double blind fashion. A single dose of aspirin was administered four hours after dosing and FEV1 was measured for six hours. Inhibition of the 5-lipoxygenase pathway by ZD2138 was assessed by measurements of urinary LTE4 levels and ex vivo calcium ionophore stimulated LTB4 generation in whole blood, before administration of drug or placebo and at regular time intervals after dosing and aspirin administration. RESULTS--ZD2138 protected against the aspirin-induced reduction in FEV1 with a 20.3 (4.9)% fall in FEV1 following placebo compared with 4.9 (2.9)% following ZD2138. This was associated with 72% inhibition of ex vivo LTB4 generation in whole blood at 12 hours and a 74% inhibition of the rise in urinary LTE4 excretion at six hours after aspirin ingestion. CONCLUSIONS--In aspirin-sensitive asthma the 5-lipoxygenase inhibitor ZD2138 inhibits the fall in FEV1 induced by aspirin and this is associated with substantial inhibition of 5-lipoxygenase. PMID:8091318

  1. Topically applied Hsp90 inhibitor 17AAG inhibits UVR-induced cutaneous squamous cell carcinomas.

    PubMed

    Singh, Anupama; Singh, Ashok; Sand, Jordan M; Bauer, Samuel J; Hafeez, Bilal Bin; Meske, Louise; Verma, Ajit K

    2015-04-01

    We present here that heat-shock protein 90 (Hsp90) inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17AAG), when topically applied to mouse skin, inhibits UVR-induced development of cutaneous squamous cell carcinoma (SCC). In these experiments, DMSO:acetone (1:40 v/v) solution of 17AAG (500 nmol) was applied topically to mouse skin in conjunction with each UVR exposure (1.8 kJ m(-2)). The UVR source was Kodacel-filtered FS-40 sun lamps (approximately 60% UVB and 40% UVA). In independent experiments with three separate mouse lines (SKH-1 hairless mice, wild-type FVB, and protein kinase C epsilon (PKCɛ)-overexpressing transgenic FVB mice), 17AAG treatment increased the latency and decreased both the incidence and multiplicity of UVR-induced SCC. Topical 17AAG alone or in conjunction with UVR treatments elicited neither skin nor systemic toxicity. 17AAG-caused inhibition of SCC induction was accompanied by a decrease in UVR-induced (1) hyperplasia, (2) Hsp90β-PKCɛ interaction, and (3) expression levels of Hsp90β, Stat3, pStat3Ser727, pStat3Tyr705, pAktSer473, and matrix metalloproteinase (MMP). The results presented here indicate that topical Hsp90 inhibitor 17AAG is effective in prevention of UVR-induced epidermal hyperplasia and SCC. One may conclude from the preclinical data presented here that topical 17AAG may be useful for prevention of UVR-induced inflammation and cutaneous SCC either developed in UVR-exposed or organ transplant population. PMID:25337691

  2. Topically applied Hsp90 inhibitor 17AAG inhibits ultraviolet radiation-induced cutaneous squamous cell carcinomas

    PubMed Central

    Singh, Anupama; Singh, Ashok; Sand, Jordan M.; Bauer, Samuel J.; Hafeez, Bilal Bin; Meske, Louise; Verma, Ajit K.

    2014-01-01

    We present here that Heat shock protein 90 (Hsp90) inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17AAG), when topically applied to mouse skin, inhibits ultraviolet radiation (UVR)-induced development of cutaneous squamous cell carcinoma (SCC). In these experiments, DMSO:acetone (1:40 v/v) solution of 17AAG (500nmol) was applied topically to mouse skin in conjunction with each UVR exposure (1.8 kJ/m2). The UVR source was Kodacel-filtered FS-40 sun lamps (approximately 60% UVB and 40% UVA). In independent experiments with three separate mouse lines (SKH-1 hairless mice, wild-type FVB, and PKCε overexpressing transgenic FVB mice), 17AAG treatment increased the latency and decreased both the incidence and multiplicity of UVR-induced SCC. Topical 17AAG alone or in conjunction with UVR treatments elicited neither skin nor systemic toxicity. 17AAG-caused inhibition of SCC induction was accompanied by decrease in UVR-induced: 1) hyperplasia, 2) Hsp90β-PKCε interaction, 3) expression levels of Hsp90β, Stat3, pStat3Ser727, pStat3Tyr705, pAktSer473 and matrix metalloproteinase (MMPs). The results presented here indicate that topical Hsp90 inhibitor 17AAG is effective in prevention of UVR-induced epidermal hyperplasia and SCC. One may conclude from the preclinical data presented here that topical 17AAG may be useful for prevention of UVR-induced inflammation and cutaneous SCC either developed in UVR exposed or organ transplant population. PMID:25337691

  3. Anti-Ulcer Efficacy of Soluble Epoxide Hydrolase Inhibitor TPPU on Diclofenac-Induced Intestinal Ulcers.

    PubMed

    Goswami, Sumanta Kumar; Wan, Debin; Yang, Jun; Trindade da Silva, Carlos A; Morisseau, Christophe; Kodani, Sean D; Yang, Guang-Yu; Inceoglu, Bora; Hammock, Bruce D

    2016-06-01

    Proton pump inhibitors such as omeprazole (OME) reduce the severity of gastrointestinal (GI) ulcers induced by nonsteroidal anti-inflammatory drugs (NSAIDs) but can also increase the chance of dysbiosis. The aim of this study was to test the hypothesis that preventive use of a soluble epoxide hydrolase inhibitor (sEHI) such as TPPU can decrease NSAID-induced ulcers by increasing anti-inflammatory epoxyeicosatrienoic acids (EETs). Dose- [10, 30, and 100 mg/kg, by mouth (PO)] and time-dependent (6 and 18 hours) ulcerative effects of diclofenac sodium (DCF, an NSAID) were studied in the small intestine of Swiss Webster mice. Dose-dependent effects of TPPU (0.001-0.1 mg/kg per day for 7 days, in drinking water) were evaluated in DCF-induced intestinal toxicity and compared with OME (20 mg/kg, PO). In addition, the effect of treatment was studied on levels of Hb in blood, EETs in plasma, inflammatory markers such as myeloperoxidase (MPO) in intestinal tissue homogenates, and tissue necrosis factor-α (TNF-α) in serum. DCF dose dependently induced ulcers that were associated with both a significant (P < 0.05) loss of Hb and an increase in the level of MPO and TNF-α, with severity of ulceration highest at 18 hours. Pretreatment with TPPU dose dependently prevented ulcer formation by DCF, increased the levels of epoxy fatty acids, including EETs, and TPPU's efficacy was comparable to OME. TPPU significantly (P < 0.05) reversed the effect of DCF on the level of Hb, MPO, and TNF-α Thus sEHI might be useful in the management of NSAID-induced ulcers. PMID:26989141

  4. Cytoprotective effect of selective small-molecule caspase inhibitors against staurosporine-induced apoptosis

    PubMed Central

    Wu, Jianghong; Wang, Yuren; Liang, Shuguang; Ma, Haiching

    2014-01-01

    Caspases are currently known as the central executioners of the apoptotic pathways. Inhibition of apoptosis and promotion of normal cell survival by caspase inhibitors would be a tremendous benefit for reducing the side effects of cancer therapy and for control of neurodegenerative disorders such as Parkinson’s, Alzheimer’s, and Huntington’s diseases. The objective of this study was to discover small-molecule caspase inhibitors with which to achieve cytoprotective effect. We completed the high-throughput screening of Bionet’s 37,500-compound library (Key Organics Limited, Camelford, Cornwall, UK) against caspase-1, -3, and -9 and successfully identified 43 initial hit compounds. The 43 hit compounds were further tested for cytoprotective activity against staurosporine-induced cell death in NIH3T3 cells. Nineteen compounds were found to have significant cytoprotective effects in cell viability assays. One of the compounds, RBC1023, was demonstrated to protect NIH3T3 cells from staurosporine-induced caspase-3 cleavage and activation. RBC1023 was also shown to protect against staurosporine-induced impairment of mitochondrial membrane potential. DNA microarray analysis demonstrated that staurosporine treatment induced broad global gene expression alterations, and RBC1023 co-treatment significantly restored these changes, especially of the genes that are related to cell growth and survival signaling such as Egr1, Cdc25c, cdkn3, Rhob, Nek2, and Taok1. Collectively, RBC1023 protects NIH3T3 cells against staurosporine-induced apoptosis via inhibiting caspase activity, restoring mitochondrial membrane potential, and possibly upregulating some cell survival-related gene expressions and pathways. PMID:24920883

  5. Histone deacetylase inhibitor treatment induces ‘BRCAness’ and synergistic lethality with PARP inhibitor and cisplatin against human triple negative breast cancer cells

    PubMed Central

    Ha, Kyungsoo; Bhaskara, Srividya; Cerchietti, Leandro; Devaraj, Santhana G. T.; Shah, Bhavin; Sharma, Sunil; Chang, Jenny C.; Melnick, Ari M.; Hiebert, Scott; Bhalla, Kapil N.

    2014-01-01

    There is an unmet need to develop new, more effective and safe therapies for the aggressive forms of triple negative breast cancers (TNBCs). While up to 20% of women under 50 years of age with TNBC harbor germline mutations in BRCA1, and these tumors are sensitive to treatment with poly(ADP) ribose polymerase inhibitors, a majority of TNBCs lack BRCA1 mutations or loss of expression. Findings presented here demonstrate that by attenuating the levels of DNA damage response and homologous recombination proteins, pan-histone deacetylase inhibitor (HDI) treatment induces ‘BRCAness’ and sensitizes TNBC cells lacking BRCA1 to lethal effects of PARP inhibitor or cisplatin. Treatment with HDI also induced hyperacetylation of nuclear hsp90. Similar effects were observed following shRNA-mediated depletion of HDAC3, confirming its role as the deacetylase for nuclear HSP90. Furthermore, cotreatment with HDI and ABT-888 induced significantly more DNA strand breaks than either agent alone, and synergistically induced apoptosis of TNBC cells. Notably, co-treatment with HDI and ABT-888 significantly reduced in vivo tumor growth and markedly improved the survival of mice bearing TNBC cell xenografts. These findings support the rationale to interrogate the clinical activity of this novel combination against human TNBC, irrespective of its expression of mutant BRCA1. PMID:25026298

  6. Histone deacetylase inhibitor treatment induces 'BRCAness' and synergistic lethality with PARP inhibitor and cisplatin against human triple negative breast cancer cells.

    PubMed

    Ha, Kyungsoo; Fiskus, Warren; Choi, Dong Soon; Bhaskara, Srividya; Cerchietti, Leandro; Devaraj, Santhana G T; Shah, Bhavin; Sharma, Sunil; Chang, Jenny C; Melnick, Ari M; Hiebert, Scott; Bhalla, Kapil N

    2014-07-30

    There is an unmet need to develop new, more effective and safe therapies for the aggressive forms of triple negative breast cancers (TNBCs). While up to 20% of women under 50 years of age with TNBC harbor germline mutations in BRCA1, and these tumors are sensitive to treatment with poly(ADP) ribose polymerase inhibitors, a majority of TNBCs lack BRCA1 mutations or loss of expression. Findings presented here demonstrate that by attenuating the levels of DNA damage response and homologous recombination proteins, pan-histone deacetylase inhibitor (HDI) treatment induces 'BRCAness' and sensitizes TNBC cells lacking BRCA1 to lethal effects of PARP inhibitor or cisplatin. Treatment with HDI also induced hyperacetylation of nuclear hsp90. Similar effects were observed following shRNA-mediated depletion of HDAC3, confirming its role as the deacetylase for nuclear HSP90. Furthermore, cotreatment with HDI and ABT-888 induced significantly more DNA strand breaks than either agent alone, and synergistically induced apoptosis of TNBC cells. Notably, co-treatment with HDI and ABT-888 significantly reduced in vivo tumor growth and markedly improved the survival of mice bearing TNBC cell xenografts. These findings support the rationale to interrogate the clinical activity of this novel combination against human TNBC, irrespective of its expression of mutant BRCA1. PMID:25026298

  7. Eribulin synergizes with Polo-like kinase 1 inhibitors to induce apoptosis in rhabdomyosarcoma.

    PubMed

    Stehle, Angelika; Hugle, Manuela; Fulda, Simone

    2015-08-28

    Eribulin, a novel microtubule-interfering drug, was recently shown to exhibit high antitumor activity in vivo against various pediatric cancers. Here, we identify a novel synthetic lethal interaction of Eribulin together with Polo-like kinase 1 (PLK1) inhibitors against rhabdomyosarcoma (RMS) in vitro and in vivo. Eribulin and the PLK1 inhibitor BI 2536 at subtoxic concentrations synergize to induce apoptosis in RMS cells as confirmed by calculation of combination index (CI). Also, Eribulin/BI 2536 co-treatment is significantly more effective than monotherapy to reduce cell viability and inhibit colony formation of RMS cells. Similarly, Eribulin and BI 2536 act in concert to trigger apoptosis in a primary, patient-derived ARMS culture, underscoring the clinical relevance of this combination. Importantly, Eribulin and BI 2536 cooperate to suppress tumor growth in an in vivo model of RMS. On molecular grounds, Eribulin/BI 2536 co-treatment causes profound mitotic arrest, which is critically required for synergism, since inhibition of mitotic arrest by CDK1 inhibitor RO-3306 abolishes Eribulin/BI 2536-mediated apoptosis. Eribulin and BI 2536 cooperate to activate caspase-9, -3 and -8, which is necessary for apoptosis induction, since the broad-range caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (zVAD.fmk) reduces Eribulin/BI 2536-induced apoptosis significantly, yet partially. Intriguingly, knockdown of endonuclease G (ENDOG) also significantly inhibits Eribulin/BI 2536-triggered apoptosis, demonstrating the involvement of both caspase-dependent and -independent effector pathways. Synergistic induction of apoptosis is similarly found for Eribulin/BI 2536 co-treatment in neuroblastoma cells and for the combination of vincristine (another antimicrotubule chemotherapeutic) with Poloxin (another PLK1 inhibitor), thus pointing to a broader significance of this concomitant microtubule- and PLK1-targeting strategy for pediatric oncology. In

  8. High rate of hematological responses to sorafenib in FLT3-ITD acute myeloid leukemia relapsed after allogeneic hematopoietic stem cell transplantation.

    PubMed

    De Freitas, Tiago; Marktel, Sarah; Piemontese, Simona; Carrabba, Matteo G; Tresoldi, Cristina; Messina, Carlo; Lupo Stanghellini, Maria Teresa; Assanelli, Andrea; Corti, Consuelo; Bernardi, Massimo; Peccatori, Jacopo; Vago, Luca; Ciceri, Fabio

    2016-06-01

    Relapse represents the most significant cause of failure of allogeneic hematopoietic stem cell transplantation (HSCT) for FLT3-ITD-positive acute myeloid leukemia (AML), and available therapies are largely unsatisfactory. In this study, we retrospectively collected data on the off-label use of the tyrosine kinase inhibitor sorafenib, either alone or in association with hypomethylating agents and adoptive immunotherapy, in 13 patients with post-transplantation FLT3-ITD-positive AML relapses. Hematological response was documented in 12 of 13 patients (92%), and five of 13 (38%) achieved complete bone marrow remission. Treatment was overall manageable in the outpatient setting, although all patients experienced significant adverse events, especially severe cytopenias (requiring a donor stem cell boost in five patients) and typical hand-foot syndrome. None of the patients developed graft-vs.-host disease following sorafenib alone, whereas this was frequently observed when this was given in association with donor T-cell infusions. Six patients are alive and in remission at the last follow-up, and four could be bridged to a second allogeneic HSCT, configuring a 65 ± 14% overall survival at 100 d from relapse. Taken together, our data suggest that sorafenib might represent a valid treatment option for patients with FLT3-ITD-positive post-transplantation relapses, manageable also in combination with other therapeutic strategies. PMID:26260140

  9. Analysis of Sorafenib Outcome: Focusing on the Clinical Course in Patients with Hepatocellular Carcinoma

    PubMed Central

    Ogasawara, Sadahisa; Chiba, Tetsuhiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Inoue, Masanori; Wakamatsu, Toru; Tawada, Akinobu; Yokosuka, Osamu

    2016-01-01

    Background Treatment outcomes of sorafenib therapy may greatly vary depending not only on tumor spread but also on past clinical processes prior to sorafenib therapy and timing of sorafenib administration in the past clinical course of hepatocellular carcinoma (HCC). We evaluated the efficacy of sorafenib in patients with HCC, taking into account of their past clinical courses. Methods Patients with HCC treated with sorafenib as a first-line systemic therapy, whose courses documented from the time of the initial diagnosis, were retrospectively analyzed. Results Of the 123 patients receiving sorafenib therapy at an advanced-stage, baseline characteristics differed including the rate of hepatitis C virus, Child–Pugh class, and status of intrahepatic lesions according to stage progression processes. Overall survival (OS) in patients progressed directly from the early-stage (15.3 months) was significantly longer than that in patients diagnosed at the advanced-stage (5.3 months, P = 0.022) and progressed from the intermediate-stages (6.0 months, P = 0.041). Of 105 patients diagnosed at the intermediate-stage on past clinical courses, OS of starting sorafenib therapy before progression to the advanced-stage (67 patients) was significantly longer than for patients starting sorafenib therapy only after progression to the advanced-stage (38 patients) (P = 0.015). Conclusion Characteristic differences between past stage progression processes might affect prognosis in advanced-stage HCC patients receiving sorafenib. Switching to sorafenib therapy before progression to the advanced-stage appears more effective than that after progression to the advanced-stage in patients diagnosed in the intermediate-stage on past clinical courses prior to sorafenib administration. PMID:27537374

  10. Pharmacologic profiling of phosphoinositide 3-kinase inhibitors as mitigators of ionizing radiation-induced cell death.

    PubMed

    Lazo, John S; Sharlow, Elizabeth R; Epperly, Michael W; Lira, Ana; Leimgruber, Stephanie; Skoda, Erin M; Wipf, Peter; Greenberger, Joel S

    2013-12-01

    Ionizing radiation (IR) induces genotoxic stress that triggers adaptive cellular responses, such as activation of the phosphoinositide 3-kinase (PI3K)/Akt signaling cascade. Pluripotent cells are the most important population affected by IR because they are required for cellular replenishment. Despite the clear danger to large population centers, we still lack safe and effective therapies to abrogate the life-threatening effects of any accidental or intentional IR exposure. Therefore, we computationally analyzed the chemical structural similarity of previously published small molecules that, when given after IR, mitigate cell death and found a chemical cluster that was populated with PI3K inhibitors. Subsequently, we evaluated structurally diverse PI3K inhibitors. It is remarkable that 9 of 14 PI3K inhibitors mitigated γIR-induced death in pluripotent NCCIT cells as measured by caspase 3/7 activation. A single intraperitoneal dose of LY294002 [2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one], administered to mice at 4 or 24 hours, or PX-867 [(4S,4aR,5R,6aS,9aR,Z)-11-hydroxy-4-(methoxymethyl)-4a,6a-dimethyl-2,7,10-trioxo-1-(pyrrolidin-1-ylmethylene)-1,2,4,4a,5,6,6a,7,8,9,9a,10-dodecahydroindeno[4,5-H]isochromen-5-yl acetate (CID24798773)], administered 4 hours after a lethal dose of γIR, statistically significantly (P < 0.02) enhanced in vivo survival. Because cell cycle checkpoints are important regulators of cell survival after IR, we examined cell cycle distribution in NCCIT cells after γIR and PI3K inhibitor treatment. LY294002 and PX-867 treatment of nonirradiated cells produced a marked decrease in S phase cells with a concomitant increase in the G1 population. In irradiated cells, LY294002 and PX-867 treatment also decreased S phase and increased the G1 and G2 populations. Treatment with LY294002 or PX-867 decreased γIR-induced DNA damage as measured by γH2AX, suggesting reduced DNA damage. These results indicate pharmacologic inhibition of PI3K after

  11. Pharmacologic Profiling of Phosphoinositide 3-Kinase Inhibitors as Mitigators of Ionizing Radiation–Induced Cell Death

    PubMed Central

    Sharlow, Elizabeth R.; Epperly, Michael W.; Lira, Ana; Leimgruber, Stephanie; Skoda, Erin M.; Wipf, Peter; Greenberger, Joel S.

    2013-01-01

    Ionizing radiation (IR) induces genotoxic stress that triggers adaptive cellular responses, such as activation of the phosphoinositide 3-kinase (PI3K)/Akt signaling cascade. Pluripotent cells are the most important population affected by IR because they are required for cellular replenishment. Despite the clear danger to large population centers, we still lack safe and effective therapies to abrogate the life-threatening effects of any accidental or intentional IR exposure. Therefore, we computationally analyzed the chemical structural similarity of previously published small molecules that, when given after IR, mitigate cell death and found a chemical cluster that was populated with PI3K inhibitors. Subsequently, we evaluated structurally diverse PI3K inhibitors. It is remarkable that 9 of 14 PI3K inhibitors mitigated γIR-induced death in pluripotent NCCIT cells as measured by caspase 3/7 activation. A single intraperitoneal dose of LY294002 [2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one], administered to mice at 4 or 24 hours, or PX-867 [(4S,4aR,5R,6aS,9aR,Z)-11-hydroxy-4-(methoxymethyl)-4a,6a-dimethyl-2,7,10-trioxo-1-(pyrrolidin-1-ylmethylene)-1,2,4,4a,5,6,6a,7,8,9,9a,10-dodecahydroindeno[4,5-H]isochromen-5-yl acetate (CID24798773)], administered 4 hours after a lethal dose of γIR, statistically significantly (P < 0.02) enhanced in vivo survival. Because cell cycle checkpoints are important regulators of cell survival after IR, we examined cell cycle distribution in NCCIT cells after γIR and PI3K inhibitor treatment. LY294002 and PX-867 treatment of nonirradiated cells produced a marked decrease in S phase cells with a concomitant increase in the G1 population. In irradiated cells, LY294002 and PX-867 treatment also decreased S phase and increased the G1 and G2 populations. Treatment with LY294002 or PX-867 decreased γIR-induced DNA damage as measured by γH2AX, suggesting reduced DNA damage. These results indicate pharmacologic inhibition of PI3K after

  12. Suppression of PRKAR1A expression enhances anti-proliferative and apoptotic effects of protein kinase inhibitors and chemotherapeutic drugs on cholangiocarcinoma cells.

    PubMed

    Loilome, Watcharin; Juntana, Sirinun; Pinitsoontorn, Chadamas; Namwat, Nisana; Tassaneeyakul, Wichittra; Yongvanit, Puangrat

    2012-01-01

    Suppression of protein kinase A regulatory subunit 1 alpha (PRKAR1A) has been proven to inhibit cholangiocarcinoma (CCA) cell growth and enhance apoptosis. In the present study, we aimed to determine synergistic and/or additive effects of chemotherapeutic agents, including protein kinase inhibitors (i.e. sorafenib, sunitinib, gefitinib, Met inhibitor) and conventional chemotherapeutic drugs (i.e. 5-fluorouracil, doxorubicin, paclitaxel, gemcitabine), in PRKARIA knockdown CCA cell lines. The results revealed that PRKAR1A suppressed CCA cell lines demonstrated enhanced sensitivity to some chemotherapeutic drugs when compared to control cells. Moreover, PRKAR1A knockdown in combination with either sorafenib or 5-fluorouracil increased apoptotic effects on CCA cell lines. Therefore, selective inhibition of PRKAR1A appears to enhance the growth inhibitory effects of chemotherapeutic drugs as well as induce apoptotic cell death. Our findings suggest that additional suppression of PRKAR1A expression may increase the efficacy of conventional CCA chemotherapeutic treatment. Clinical studies in CCA patients now need to be conducted. PMID:23480756

  13. Respiratory inhibitors and uncouplers prevent the aeration-induced increase in mitochondrial anion conductivity.

    PubMed Central

    Halle-Smith, S C; Selwyn, M J

    1990-01-01

    1. When mitochondria are stirred in air the rate of anion conductivity increases, this effect being enhanced by the addition of respiratory substrate. 2. This effect is reversible if the mitochondria are stored for a period of time under N2. 3. The aeration-induced increase in mitochondrial anion conductivity can also be prevented by the addition of respiratory inhibitors rotenone and antimycin A, as well as by 30 microM-cyanide. 4. A decrease in this aeration-induced anion conductivity can also be observed upon the addition of the uncouplers carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (2 microM) and 2,4-dinitrophenol (100 microM). 5. Simultaneous measurements of mitochondrial anion conductivity and membrane potential show a relationship between the level of membrane potential and anion conductivity. 6. It is suggested that the level of membrane potential is either directly or indirectly responsible for the level of mitochondrial anion conductivity. PMID:2327957

  14. Respiratory inhibitors and uncouplers prevent the aeration-induced increase in mitochondrial anion conductivity.

    PubMed

    Halle-Smith, S C; Selwyn, M J

    1990-03-15

    1. When mitochondria are stirred in air the rate of anion conductivity increases, this effect being enhanced by the addition of respiratory substrate. 2. This effect is reversible if the mitochondria are stored for a period of time under N2. 3. The aeration-induced increase in mitochondrial anion conductivity can also be prevented by the addition of respiratory inhibitors rotenone and antimycin A, as well as by 30 microM-cyanide. 4. A decrease in this aeration-induced anion conductivity can also be observed upon the addition of the uncouplers carbonyl cyanide p-(trifluoromethoxy)phenylhydrazone (2 microM) and 2,4-dinitrophenol (100 microM). 5. Simultaneous measurements of mitochondrial anion conductivity and membrane potential show a relationship between the level of membrane potential and anion conductivity. 6. It is suggested that the level of membrane potential is either directly or indirectly responsible for the level of mitochondrial anion conductivity. PMID:2327957

  15. Cyclooxygenase inhibitor induces the upregulation of connexin-43 expression in C6 glioma cells

    PubMed Central

    QIN, LI-JUAN; JIA, YONG-SEN; ZHANG, YI-BING; WANG, YIN-HUAN

    2016-01-01

    The present study was performed to determine whether aspirin, a cyclooxygenase (COX) inhibitor, has an effect on the expression of connexin 43 (Cx43) in C6 glioma cells. Using an in vitro glioma invasion model, the expression of Cx43 protein in C6 cells was significantly increased following aspirin treatment at a dose of 8 mmol/l for 30, 60 and 120 min via western blot analysis. The peak value of the Cx43 expression was observed in C6 cells after 120 min of aspirin treatment, which was significantly reduced by prostaglandin E2 (PGE2). In addition, aspirin also significantly increased the gap junction intercellular communication (GJIC) activity and reduced glioma invasion, which was induced by PGE2. This led to the conclusion that the aspirin-induced glioma invasion decrease may be associated with the increased expression of Cx43 protein and formation of GJIC. PMID:27073629

  16. A clinical phase II study with sorafenib in patients with progressive hormone-refractory prostate cancer: a study of the CESAR Central European Society for Anticancer Drug Research-EWIV

    PubMed Central

    Steinbild, S; Mross, K; Frost, A; Morant, R; Gillessen, S; Dittrich, C; Strumberg, D; Hochhaus, A; Hanauske, A-R; Edler, L; Burkholder, I; Scheulen, M

    2007-01-01

    Sorafenib is a multi-kinase inhibitor with antiangiogenic and antiproliferative activity. The activity of sorafenib in progressive hormone-refractory prostate cancer (HRPC) patients was investigated in a phase II clinical study. Progressive HRPC patients received sorafenib 400 mg bid p.o. continuously. Only patients with no prior chemotherapy, and either one-unidimensional measurable lesion according to RECIST-criteria or increasing prostate-specific antigen (PSA) values reflecting a hormone-refractory situation, were eligible for study entry. The primary study objective was the rate of progression-free survival of ⩾12 weeks (PFS12). Secondary end points were overall response, overall survival, and toxicity. Fifty-seven patients with PC were enrolled. Two patients had to be withdrawn from the set of eligible patients. According to RECIST criteria, 4 patients out of 55 evaluable patients showed stable disease (SD). According to PSA–response, we saw 11 patients with SD PSA and 2 patients were responders at 12 weeks (PFS12=17/55=31%). Among the 257 adverse events, 15 were considered drug related of maximum CTC-grade 3. Twenty-four serious adverse events occurred in 14 patients (14/55=26%). Seven of them were determined to be drug related. No treatment-related death was observed. Sorafenib has antitumour activity in HRPCP when evaluated for RECIST- and PSA-based response. Further investigation as a component of combination regimens is necessary to evaluate its definite or overall clinical benefit for HRPCP. PMID:18040273

  17. The dietary histone deacetylase inhibitor sulforaphane induces human β-defensin-2 in intestinal epithelial cells

    PubMed Central

    Schwab, Markus; Reynders, Veerle; Loitsch, Stefan; Steinhilber, Dieter; Schröder, Oliver; Stein, Jürgen

    2008-01-01

    Antimicrobial peptides like human β-defensin-2 (HBD-2) play an important role in the innate immune system protecting the intestinal mucosa against bacterial invasion. The dietary histone deacetylase (HDAC) inhibitors sulforaphane (SFN) and butyrate have received a great deal of attention because of their ability to simultaneously modulate multiple cellular targets involved in cellular protection. In this study the influence of SFN and butyrate on HBD-2 expression as well as the molecular pathways involved in SFN-mediated induction of HBD-2 were scrutinized. Treatment of Caco-2, HT-29 and SW480 cells with SFN led to a time- and dose-dependent upregulation of HBD-2 mRNA expression as determined by semi-quantitative reverse transcription–polymerase chain reaction. Moreover, HBD-2 protein production increased in response to SFN, measured by enzyme-linked immunosorbent assay. Induction of HBD-2 was also observed in response to butyrate. Immunofluorescence analysis revealed that the protein was localized in the cytosol. Coincubation of SFN with a vitamin D receptor (VDR), or an extracellular-regulated kinase 1/2 or a nuclear factor-κB inhibitor all reduced HBD-2 mRNA upregulation. In contrast, transfection of cells with a dominant-negative peroxisome proliferator-activated receptor γ (PPARγ) mutant vector to inhibit PPARγ wild-type action and inhibition of p38 mitogen-activated protein kinase (MAPK) signalling did not affect SFN-mediated upregulation of HBD-2 mRNA. Moreover, SFN induced the expression of VDR, PPARγ and phosphorylated ERK1/2 but did not affect p38 MAPK activation. The data clearly demonstrate for the first time that the dietary HDAC inhibitor SFN is able to induce antimicrobial peptides in colonocytes. In this process HBD-2 expression is regulated via VDR, mitogen-activated protein kinase kinase/extracellular-regulated kinase and nuclear factor-κB signalling. PMID:18373608

  18. KEAP1-dependent synthetic lethality induced by AKT and TXNRD1 inhibitors in lung cancer

    PubMed Central

    Dai, Bingbing; Yoo, Suk-Yuong; Bartholomeusz, Geoffrey; Graham, Ryan A.; Majidi, Mourad; Yan, Shaoyu; Meng, Jieru; Ji, Lin; Coombes, Kevin; Minna, John D.; Fang, Bingliang; Roth, Jack A.

    2013-01-01

    Intrinsic resistance to agents targeting phosphatidylinositol-3-kinase (PI3K)/AKT pathway is one of the major challenges in cancer treatment with such agents. The objective of this study is to identify the genes or pathways that can be targeted to overcome the resistance of non-small cell lung cancer to the AKT inhibitor, MK2206, which is currently being evaluated in phase I and II clinical trials. Using a genome-wide small interfering RNA (siRNA) library screening and biological characterization we identified that inhibition of Thioredoxin Reductase-1 (TXNRD1), one of the key anti-oxidant enzymes, with siRNAs or its inhibitor, Auranofin, sensitized non-small cell lung cancer cells to MK2206 treatment in vitro and in vivo. We found that simultaneous inhibition of TXNRD1 and AKT pathways induced robust reactive oxygen species (ROS) production, which was involved in c-Jun N-terminal Kinase (JNK, MAPK8) activation and cell apoptosis. Furthermore we found that the synthetic lethality interaction between the TXNRD1 and AKT pathways occurred through the KEAP1/NRF2 cellular antioxidant pathway. Lastly, we found that synthetic lethality induced by TXNRD1 and AKT inhibitors relied on wild type KEAP1 function. Our study indicates that targeting the interaction between AKT and TXNRD1 antioxidant pathways with MK2206 and Auranofin, a FDA approved drug, is a rational strategy to treat lung cancer and that KEAP1 mutation status may offer a predicative biomarker for such combination approaches. PMID:23824739

  19. Phenotypic Screening Identifies Protein Synthesis Inhibitors as H-Ras-Nanocluster-Increasing Tumor Growth Inducers.

    PubMed

    Najumudeen, Arafath K; Posada, Itziar M D; Lectez, Benoit; Zhou, Yong; Landor, Sebastian K-J; Fallarero, Adyary; Vuorela, Pia; Hancock, John; Abankwa, Daniel

    2015-12-15

    Ras isoforms H-, N-, and K-ras are each mutated in specific cancer types at varying frequencies and have different activities in cell fate control. On the plasma membrane, Ras proteins are laterally segregated into isoform-specific nanoscale signaling hubs, termed nanoclusters. As Ras nanoclusters are required for Ras signaling, chemical modulators of nanoclusters represent ideal candidates for the specific modulation of Ras activity in cancer drug development. We therefore conducted a chemical screen with commercial and in-house natural product libraries using a cell-based H-ras-nanoclustering FRET assay. Next to established Ras inhibitors, such as a statin and farnesyl-transferase inhibitor, we surprisingly identified five protein synthesis inhibitors as positive regulators. Using commonly employed cycloheximide as a representative compound, we show that protein synthesis inhibition increased nanoclustering and effector recruitment specifically of active H-ras but not of K-ras. Consistent with these data, cycloheximide treatment activated both Erk and Akt kinases and specifically promoted H-rasG12V-induced, but not K-rasG12V-induced, PC12 cell differentiation. Intriguingly, cycloheximide increased the number of mammospheres, which are enriched for cancer stem cells. Depletion of H-ras in combination with cycloheximide significantly reduced mammosphere formation, suggesting an exquisite synthetic lethality. The potential of cycloheximide to promote tumor cell growth was also reflected in its ability to increase breast cancer cell tumors grown in ovo. These results illustrate the possibility of identifying Ras-isoform-specific modulators using nanocluster-directed screening. They also suggest an unexpected feedback from protein synthesis inhibition to Ras signaling, which might present a vulnerability in certain tumor cell types. PMID:26568031

  20. Identification of H7 as a novel peroxiredoxin I inhibitor to induce differentiation of leukemia cells

    PubMed Central

    Qin, Dongjun; Chen, Yingyi; Liu, Chuanxu; Xia, Li; Wang, Tongdan; Lei, Hu; Yu, Yun; Huang, Min; Tong, Yin; Xu, Hanzhang; Gao, Fenghou

    2016-01-01

    Identifying novel targets to enhance leukemia-cell differentiation is an urgent requirment. We have recently proposed that inhibiting the antioxidant enzyme peroxiredoxin I (Prdx I) may induce leukemia-cell differentiation. However, this concept remains to be confirmed. In this work, we identified H7 as a novel Prdx I inhibitor through virtual screening, in vitro activity assay, and surface plasmon resonance assay. Cellular thermal shift assay showed that H7 directly bound to Prdx I but not to Prdxs II–V in cells. H7 treatment also increased reactive oxygen species (ROS) level and cell differentiation in leukemia cells, as reflected by the upregulation of the cell surface differentiation marker CD11b/CD14 and the morphological maturation of cells. The differentiation-induction effect of H7 was further observed in some non-acute promyelocytic leukemia (APL) and primary leukemia cells apart from APL NB4 cells. Moreover, the ROS scavenger N-acetyl cysteine significantly reversed the H7-induced cell differentiation. We demonstrated as well that H7-induced cell differentiation was associated with the activation of the ROS-Erk1/2-C/EBPβ axis. Finally, we showed H7 treatment induced cell differentiation in an APL mouse model. All of these data confirmed that Prdx I was novel target for inducing leukemia-cell differentiation and that H7 was a novel lead compound for optimizing Prdx I inhibition. PMID:26716647

  1. Effects of matrix metalloproteinase inhibitor on LPS-induced goblet cell metaplasia.

    PubMed

    Kim, Je Hyeong; Lee, Sung Yong; Bak, Sang Myeon; Suh, In Bum; Lee, Sang Yeub; Shin, Chol; Shim, Jae Jeong; In, Kwang Ho; Kang, Kyung Ho; Yoo, Se Hwa

    2004-07-01

    Bacterial infections of the lung are known to induce inflammatory responses, which lead to mucus hypersecretion. Moreover, mucin synthesis in the airways has been reported to be regulated by neutrophilic inflammation-induced epidermal growth factor receptor (EGFR) expression and its activation. Furthermore, matrix metalloproteinases (MMPs), especially MMP-9, have been reported to promote the transmigration of activated neutrophils. In this study, we investigated the associations between lipopolysaccharide (LPS)-induced goblet cell (GC) metaplasia and EGFR expression and the effects of MMP inhibitor (MMPI). Various concentrations of LPS were instilled into the tracheas of pathogen-free Sprague-Dawley rats, and airways were examined at different times after LPS instillation. To examine the role of MMP-9, we treated rats 3 days before LPS instillation and daily thereafter with MMPI. Neutrophilic infiltration, Alcian blue/periodic acid-Schiff (AB/PAS) staining, and immunohistochemical staining for MUC5AC, EGFR, and MMP-9 were performed. The instillation of LPS increased AB/PAS and MUC5AC staining in time- and dose-dependent manners, and treatment with MMPI significantly prevented GC metaplasia. The instillation of LPS into the trachea also induced neutrophilic infiltration and EGFR and MMP-9 expression in the airway epithelium, and MMPI was found to significantly prevent neutrophil recruitment, GC metaplasia, and EGFR and MMP-9 expression. This study demonstrates that the MMP-9 and EGFR cascades are associated with LPS-induced mucus hypersecretion. PMID:15020297

  2. Histone deacetylase inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats

    PubMed Central

    Lee, Eunjo; Song, Min-ji; Lee, Hae-Ahm; Kang, Seol-Hee; Kim, Mina; Yang, Eun Kyoung; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung

    2016-01-01

    CG200745 is a novel inhibitor of histone deacetylases (HDACs), initially developed for treatment of various hematological and solid cancers. Because it is water-soluble, it can be administered orally. We hypothesized that the HDAC inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in deoxycorticosterone acetate (DOCA)-induced hypertensive rats. For establishment of hypertension, 40 mg/kg of DOCA was subcutaneously injected four times weekly into Sprague-Dawley rats. All the rats used in this study including those in the sham group had been unilaterally nephrectomized and allowed free access to drinking water containing 1% NaCl. Systolic blood pressure was measured by the tail-cuff method. Blood chemistry including sodium, potassium, glucose, triglyceride, and cholesterol levels was analyzed. Sections of the heart were visualized after trichrome and hematoxylin and eosin stain. The expression of hypertrophic genes such as atrial natriuretic peptide A (Nppa) and atrial natriuretic peptide B (Nppb) in addition to fibrotic genes such as Collagen-1, Collagen-3, connective tissue growth factor (Ctgf), and Fibronectin were measured by quantitative real-time PCR (qRT-PCR). Injection of DOCA increased systolic blood pressure, heart weight, and cardiac fibrosis, which was attenuated by CG200745. Neither DOCA nor CG200745 affected body weight, vascular contraction and relaxation responses, and blood chemistry. Injection of DOCA increased expression of both hypertrophic and fibrotic genes, which was abrogated by CG200745. These results indicate that CG200745 attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats. PMID:27610034

  3. Icariside II, a novel phosphodiesterase-5 inhibitor, attenuates streptozotocin-induced cognitive deficits in rats.

    PubMed

    Yin, Caixia; Deng, Yuanyuan; Gao, Jianmei; Li, Xiaohui; Liu, Yuangui; Gong, Qihai

    2016-07-22

    Beta-amyloid (Aβ) deposition and neuroinflammation are involved in Alzheimer's disease (AD)-type neurodegeneration with cognitive deficits. Phosphodiesterase-5 (PDE5) inhibitors have recently been studied as a potential target for cognitive enhancement by reducing inflammatory responses and Aβ levels. The present study was designed to investigate the effects of icariside II (ICS II), a novel PDE5 inhibitor derived from the traditional Chinese herb Epimedium brevicornum, on cognitive deficits, Aβ levels and neuroinflammation induced by intracerebroventricular-streptozotocin (ICV-STZ) in rats. The results demonstrated that ICV-STZ exhibited cognitive deficits and neuronal morphological damage, along with Aβ increase and neuroinflammation in the rat hippocampus. ICS II improved cognitive deficits, attenuated neuronal death, and decreased the levels of Aβ1-40, Aβ1-42 and PDE5 in the hippocampus of STZ rats. Furthermore, administration of ICS II at the dose of 10mg/kg for 21days significantly suppressed the expression of beta-amyloid precursor protein (APP), beta-secretase1 (BACE1) and increased the expressions of neprilysin (NEP) together with inhibited interleukin-1β (IL-1β), tumor necrosis factor (TNF)-α, cyclooxygenase-2 (COX-2) and transforming growth factor-β1 (TGF-β1) levels. In addition, ICS II exerted a beneficial effect on inhibition of IκB-α degradation and NF-κB activation induced by STZ. Taken together, the present study demonstrated that ICS II was a potential therapeutic agent for AD treatment. PMID:27109920

  4. Histone deacetylase inhibitors induce growth arrest and differentiation in uveal melanoma

    PubMed Central

    Landreville, Solange; Agapova, Olga A.; Matatall, Katie A.; Kneass, Zachary T.; Onken, Michael D.; Lee, Ryan S.; Bowcock, Anne M.; Harbour, J. William

    2011-01-01

    Purpose Metastasis is responsible for the death of most cancer patients, yet few therapeutic agents are available which specifically target the molecular events that lead to metastasis. We recently showed that inactivating mutations in the tumor suppressor gene BAP1 are closely associated with loss of melanocytic differentiation in uveal melanoma and metastasis (UM). The purpose of this study was to identify therapeutic agents that reverse the phenotypic effects of BAP1 loss in UM. Experimental Design In silico screens were performed to identify therapeutic compounds predicted to differentiate UM cells using Gene Set Enrichment Analysis and Connectivity Map databases. Valproic acid, trichostatin A, LBH-589 and suberoylanilide hydroxamic acid were evaluated for their effects on UM cells using morphologic evaluation, MTS viability assays, BrdU incorporation, flow cytometry, clonogenic assays, gene expression profiling, histone acetylation and ubiquitination assays, and a murine xenograft tumorigenicity model. Results HDAC inhibitors induced morphologic differentiation, cell cycle exit, and a shift to a differentiated, melanocytic gene expression profile in cultured UM cells. Valproic acid inhibited the growth of UM tumors in vivo. Conclusions These findings suggest that HDAC inhibitors may have therapeutic potential for inducing differentiation and prolonged dormancy of micrometastatic disease in UM. PMID:22038994

  5. Histone Deacetylase Inhibitors: The Epigenetic Therapeutics That Repress Hypoxia-Inducible Factors

    PubMed Central

    Chen, Shuyang; Sang, Nianli

    2011-01-01

    Histone deacetylase inhibitors (HDACIs) have been actively explored as a new generation of chemotherapeutics for cancers, generally known as epigenetic therapeutics. Recent findings indicate that several types of HDACIs repress angiogenesis, a process essential for tumor metabolism and progression. Accumulating evidence supports that this repression is mediated by disrupting the function of hypoxia-inducible factors (HIF-1, HIF-2, and collectively, HIF), which are the master regulators of angiogenesis and cellular adaptation to hypoxia. Since HIF also regulate glucose metabolism, cell survival, microenvironment remodeling, and other alterations commonly required for tumor progression, they are considered as novel targets for cancer chemotherapy. Though the precise biochemical mechanism underlying the HDACI-triggered repression of HIF function remains unclear, potential cellular factors that may link the inhibition of deacetylase activity to the repression of HIF function have been proposed. Here we review published data that inhibitors of type I/II HDACs repress HIF function by either reducing functional HIF-1α levels, or repressing HIF-α transactivation activity. In addition, underlying mechanisms and potential proteins involved in the repression will be discussed. A thorough understanding of HDACI-induced repression of HIF function may facilitate the development of future therapies to either repress or promote angiogenesis for cancer or chronic ischemic disorders, respectively. PMID:21151670

  6. Histone deacetylase inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats.

    PubMed

    Lee, Eunjo; Song, Min-Ji; Lee, Hae-Ahm; Kang, Seol-Hee; Kim, Mina; Yang, Eun Kyoung; Lee, Do Young; Ro, Seonggu; Cho, Joong Myung; Kim, Inkyeom

    2016-09-01

    CG200745 is a novel inhibitor of histone deacetylases (HDACs), initially developed for treatment of various hematological and solid cancers. Because it is water-soluble, it can be administered orally. We hypothesized that the HDAC inhibitor, CG200745, attenuates cardiac hypertrophy and fibrosis in deoxycorticosterone acetate (DOCA)-induced hypertensive rats. For establishment of hypertension, 40 mg/kg of DOCA was subcutaneously injected four times weekly into Sprague-Dawley rats. All the rats used in this study including those in the sham group had been unilaterally nephrectomized and allowed free access to drinking water containing 1% NaCl. Systolic blood pressure was measured by the tail-cuff method. Blood chemistry including sodium, potassium, glucose, triglyceride, and cholesterol levels was analyzed. Sections of the heart were visualized after trichrome and hematoxylin and eosin stain. The expression of hypertrophic genes such as atrial natriuretic peptide A (Nppa) and atrial natriuretic peptide B (Nppb) in addition to fibrotic genes such as Collagen-1, Collagen-3, connective tissue growth factor (Ctgf), and Fibronectin were measured by quantitative real-time PCR (qRT-PCR). Injection of DOCA increased systolic blood pressure, heart weight, and cardiac fibrosis, which was attenuated by CG200745. Neither DOCA nor CG200745 affected body weight, vascular contraction and relaxation responses, and blood chemistry. Injection of DOCA increased expression of both hypertrophic and fibrotic genes, which was abrogated by CG200745. These results indicate that CG200745 attenuates cardiac hypertrophy and fibrosis in DOCA-induced hypertensive rats. PMID:27610034

  7. Histone deacetylase inhibitors and aspirin interact synergistically to induce cell death in ovarian cancer cells.

    PubMed

    Sonnemann, Jürgen; Hüls, Isabel; Sigler, Michael; Palani, Chithra D; Hong, Le Thi Thu; Völker, Uwe; Kroemer, Heyo K; Beck, James F

    2008-07-01

    Histone deacetylase inhibitors (HDIs) as well as non-steroidal anti-inflammatory drugs including aspirin show promise as antineoplastic agents. The treatment with both HDIs and aspirin can result in hyperacetylation of proteins. In this study, we investigated whether HDIs and aspirin interacted in inducing anticancer activity and histone acetylation. We found that the HDIs, suberoylanilide hydroxamic acid and sodium butyrate, and aspirin cooperated to induce cell death in the ovarian cancer cell line, A2780. The effect was synergistic, as evidenced by CI-isobologram analysis. However, aspirin had no effect on histone acetylation, neither in the absence nor presence of HDIs. To gain insight into the mechanism underlying the synergistic action of HDIs and aspirin, we employed the deacetylated metabolite of aspirin, salicylic acid, and the cyclooxygenase-1- and -2-selective inhibitors, SC-560 and NS-398, respectively. We found that HDIs and salicylic acid interacted synergistically, albeit less efficiently than HDIs and aspirin, to induce cancer cell death, suggesting that the acetyl and the salicyl moiety contributed to the cooperative interaction of aspirin with HDIs. SC-560 and NS-398 had little effect both when applied alone or in conjunction with HDIs, indicating that the combinatorial effect of HDIs and aspirin was not the result of cyclo-oxygenase inhibition. In conclusion, our study demonstrates that HDIs and aspirin synergize to induce cancer cell death and, thus, provides a rationale for a more in-depth exploration into the potential of combining HDIs and aspirin as a strategy for anticancer therapy. PMID:18575740

  8. Bowman-Birk protease inhibitor from soybeans enhances cisplatin-induced cytotoxicity in human mesothelioma cells

    PubMed Central

    KASHIWAGI, KOREHITO; VIRGONA, NANTIGA; YAMADA, JIN; SATO, AYAMI; OTA, MASAKO; YAZAWA, TAKUYA; YANO, TOMOHIRO

    2011-01-01

    Malignant mesothelioma (MM) is an aggressive cancer with no effective treatment options. Enforced expression of the gap junction (GJ) component connexin 43 (Cx43) increases the sensitivity of MM cells to cisplatin. Bowman-Birk protease inhibitor (BBI) induces the restoration of Cx43 in several types of tumor cells. In this study, we examined the capability of BBI to enhance the cytotoxic effect of cisplatin in MM cells via the induction of Cx43. Human MM H28 cells were used. Cell viability was evaluated by a WST-1 assay and proteasomal activity was determined by fluorometric analysis. Protein and mRNA levels were determined by immunoblot analysis and real-time RT-PCR, respectively. GJ function mediated by Cx43 was evaluated using the scrape-loading method. BBI effectively inhibited H28 cell growth in a dose-dependent manner (200–400 μg/ml). In parallel with the growth inhibition, Cx43 levels (mRNA and protein) and GJ function were elevated by BBI treatment. Knockdown of BBI-induced Cx43 by an antisense nucleotide treatment almost cancelled the growth inhibition. BBI enhanced cisplatin-induced cytotoxicity in H28 cells, and down-regulation of Cx43 by the antisense nucleotide treatment abrogated the enhancing effect of BBI. The induction of Cx43 by BBI contributed to Src inactivation and subsequent induction of Bax. Furthermore, an Src inhibitor (SU6656) also enhanced cisplatin-induced cytotoxicity in H28 cells. These results suggest that BBI improves the cytotoxic efficacy of cisplatin in H28 cells via the inhibition of Src signaling. PMID:22977565

  9. Induced Resistance to Methionyl-tRNA Synthetase Inhibitors in Trypanosoma brucei Is Due to Overexpression of the Target

    PubMed Central

    Ranade, Ranae M.; Gillespie, J. Robert; Shibata, Sayaka; Verlinde, Christophe L. M. J.; Fan, Erkang; Hol, Wim G. J.

    2013-01-01

    New classes of antiparasitic drugs active against Trypanosoma brucei are needed to combat human African trypanosomiasis. Inhibitors of methionyl-tRNA synthetase (MetRS) have excellent potential to be developed for this purpose (S. Shibata, J. R. Gillespie, A. M. Kelley, A. J. Napuli, Z. Zhang, K. V. Kovzun, R. M. Pefley, J. Lam, F. H. Zucker, W. C. Van Voorhis, E. A. Merritt, W. G. Hol, C. L. Verlinde, E. Fan, and F. S. Buckner, Antimicrob. Agents Chemother. 55:1982–1989, 2011). In order to assess the potential for resistance to develop against this new class of inhibitors, T. brucei cultures were grown in the presence of MetRS inhibitors or comparison drugs. Resistance up to ∼50 times the baseline 50% inhibitory concentration (IC50) was induced against a MetRS inhibitor after ∼120 days. A similar level of resistance to the clinical drug eflornithine was induced after ∼50 days and for pentamidine after ∼80 days. Thus, resistance was induced more slowly against MetRS inhibitors than against clinically used drugs. The parasites resistant to the MetRS inhibitor were shown to overexpress MetRS mRNA by a factor of 35 over the parental strain. Southern analysis indicated that the MetRS gene was amplified in the genome by nearly 8-fold. When injected into mice, the MetRS inhibitor-resistant parasites caused a reduced level of infection, indicating that the changes associated with resistance attenuated their virulence. This finding and the fact that resistance to MetRS inhibitors developed relatively slowly are encouraging for further development of this class of compounds. Published studies on other antitrypanosomal drugs have primarily shown that alterations in membrane transporters were the mechanisms responsible for resistance. This is the first published report of induced drug resistance in the African trypanosome due to overexpression of the target enzyme. PMID:23587950

  10. Effect of the Angiotensin I Converting Enzyme Inhibitor, MK-421, on Experimentally Induced Drinking

    NASA Technical Reports Server (NTRS)

    Fregley, Melvin J.; Fater, Dennis C.; Greenleaf, John E.

    1982-01-01

    MK-421, the ethyl ester maleate salt of N-(S)-1-(ethoxycarbonyl)-3-phenyl-propyl- Ala-L-Pro, is an angiotensin I converting enzyme inhibitor. An initial objective was to determine whether MK-421, administered at 0, 2.5, 5.0, 10.0, 20.0 and 40.0 mg/kg, ip to 96 female rats 15 min prior to administration of the beta-adrenergic agonist, isoproterenol (25 microgram/kg, ip), would inhibit the drinking induced by isoproterenol during 2 h after its administration. The water intake induced by isoproterenol was inhibited significantly by 2.5 mg MK-421/kg. When a similar experiment was performed using Angiotensin I (AI) (200 microgram/kg, ip) as the dipsogenic agent, MK-421 (5 mg/kg, ip), administered 15 min prior to AI, inhibited significantly both the dipsogenic and the diuretic effect of AI. However, administration of angiotensin II (AII, 200 microgram/kg, ip) 15 min after MK-421 (5mg/kg) was accompanied by a water intake that did not differ from AII alone. The drink induced by ip administration of 1.0 m NaCl solution (1% of body wt, ip) was not inhibited by administration of MK-421 (5 mg/kg) 15 min prior to allowing access to water while the drink induced by a 24 h dehydration was partially inhibited. Thus, the drinks induced by administraition of either isoproterenol or AI are dependent on formation of AII. That induced by dehydration is partially dependent, while that induced by hypertonic siilinc is independent of the formation of AII.

  11. A rat retinal damage model predicts for potential clinical visual disturbances induced by Hsp90 inhibitors

    SciTech Connect

    Zhou, Dan; Liu, Yuan; Ye, Josephine; Ying, Weiwen; Ogawa, Luisa Shin; Inoue, Takayo; Tatsuta, Noriaki; Wada, Yumiko; Koya, Keizo; Huang, Qin; Bates, Richard C.; Sonderfan, Andrew J.

    2013-12-01

    In human trials certain heat shock protein 90 (Hsp90) inhibitors, including 17-DMAG and NVP-AUY922, have caused visual disorders indicative of retinal dysfunction; others such as 17-AAG and ganetespib have not. To understand these safety profile differences we evaluated histopathological changes and exposure profiles of four Hsp90 inhibitors, with or without clinical reports of adverse ocular effects, using a rat retinal model. Retinal morphology, Hsp70 expression (a surrogate marker of Hsp90 inhibition), apoptotic induction and pharmacokinetic drug exposure analysis were examined in rats treated with the ansamycins 17-DMAG and 17-AAG, or with the second-generation compounds NVP-AUY922 and ganetespib. Both 17-DMAG and NVP-AUY922 induced strong yet restricted retinal Hsp70 up-regulation and promoted marked photoreceptor cell death 24 h after the final dose. In contrast, neither 17-AAG nor ganetespib elicited photoreceptor injury. When the relationship between drug distribution and photoreceptor degeneration was examined, 17-DMAG and NVP-AUY922 showed substantial retinal accumulation, with high retina/plasma (R/P) ratios and slow elimination rates, such that 51% of 17-DMAG and 65% of NVP-AUY922 present at 30 min post-injection were retained in the retina 6 h post-dose. For 17-AAG and ganetespib, retinal elimination was rapid (90% and 70% of drugs eliminated from the retina at 6 h, respectively) which correlated with lower R/P ratios. These findings indicate that prolonged inhibition of Hsp90 activity in the eye results in photoreceptor cell death. Moreover, the results suggest that the retina/plasma exposure ratio and retinal elimination rate profiles of Hsp90 inhibitors, irrespective of their chemical class, may predict for ocular toxicity potential. - Highlights: • In human trials some Hsp90 inhibitors cause visual disorders, others do not. • Prolonged inhibition of Hsp90 in the rat eye results in photoreceptor cell death. • Retina/plasma ratio and retinal

  12. Phosphodiesterase 5 inhibitors prevent 3,4-methylenedioxymethamphetamine-induced 5-HT deficits in the rat.

    PubMed

    Puerta, Elena; Hervias, Isabel; Goñi-Allo, Beatriz; Lasheras, Berta; Jordan, Joaquin; Aguirre, Norberto

    2009-02-01

    inhibitor. In conclusion, sildenafil protects against MDMA-induced long-term reduction of indoles by a mechanism involving increased production of cGMP and subsequent activation of PKG and mitochondrial ATP-sensitive K(+) channel opening. PMID:19187094

  13. The B-RafV600E inhibitor dabrafenib selectively inhibits RIP3 and alleviates acetaminophen-induced liver injury

    PubMed Central

    Li, J-X; Feng, J-M; Wang, Y; Li, X-H; Chen, X-X; Su, Y; Shen, Y-Y; Chen, Y; Xiong, B; Yang, C-H; Ding, J; Miao, Z-H

    2014-01-01

    Receptor-interacting protein (RIP)3 is a critical regulator of necroptosis and has been demonstrated to be associated with various diseases, suggesting that its inhibitors are promising in the clinic. However, there have been few RIP3 inhibitors reported as yet. B-RafV600E inhibitors are an important anticancer drug class for metastatic melanoma therapy. In this study, we found that 6 B-Raf inhibitors could inhibit RIP3 enzymatic activity in vitro. Among them, dabrafenib showed the most potent inhibition on RIP3, which was achieved by its ATP-competitive binding to the enzyme. Dabrafenib displayed highly selective inhibition on RIP3 over RIP1, RIP2 and RIP5. Moreover, only dabrafenib rescued cells from RIP3-mediated necroptosis induced by the necroptosis-induced combinations, that is, tumor necrosis factor (TNF)α, TNF-related apoptosis-inducing ligand or Fas ligand plus Smac mimetic and the caspase inhibitor z-VAD. Dabrafenib decreased the RIP3-mediated Ser358 phosphorylation of mixed lineage kinase domain-like protein (MLKL) and disrupted the interaction between RIP3 and MLKL. Notably, RIP3 inhibition of dabrafenib appeared to be independent of its B-Raf inhibition. Dabrafenib was further revealed to prevent acetaminophen-induced necrosis in normal human hepatocytes, which is considered to be mediated by RIP3. In acetaminophen-overdosed mouse models, dabrafenib was found to apparently ease the acetaminophen-caused liver damage. The results indicate that the anticancer B-RafV600E inhibitor dabrafenib is a RIP3 inhibitor, which could serve as a sharp tool for probing the RIP3 biology and as a potential preventive or therapeutic agent for RIP3-involved necroptosis-related diseases such as acetaminophen-induced liver damage. PMID:24901049

  14. Inhibition of polyamine oxidase prevented cyclin-dependent kinase inhibitor-induced apoptosis in HCT 116 colon carcinoma cells.

    PubMed

    Gürkan, Ajda Coker; Arisan, Elif Damla; Obakan, Pinar; Palavan-Ünsal, Narçin

    2013-12-01

    Roscovitine and purvalanol are novel cyclin-dependent kinase (CDK) inhibitors that prevent cell proliferation and induce apoptotic cell death in various cancer cell lines. Although a number of studies have demonstrated the potential apoptotic role of roscovitine, there is limited data about the therapeutic efficiency of purvalanol on cancer cells. The natural polyamines (PAs) putrescine, spermidine, and spermine have essential roles in the regulation of cell differentiation, growth, and proliferation, and increased levels of these compounds have been associated with cancer progression. Recently, depletion of intracellular PA levels because of modulation of PA catabolic enzymes was shown to be an indicator of the efficacy of chemotherapeutic agents. In this study, our aim was to investigate the potential role of PA catabolic enzymes in CDK inhibitor-induced apoptosis in HCT 116 colon carcinoma cells. Exposure of cells to roscovitine or purvalanol decreased cell viability in a dose- and time-dependent manner. The selected concentrations of roscovitine and purvalanol inhibited cell viability by 50 % compared with control cells and induced apoptosis by activating the mitochondria-mediated pathway in a caspase-dependent manner. However, the apoptotic effect of purvalanol was stronger than that of roscovitine in HCT 116 cells. In addition, we found that CDK inhibitors decreased PA levels and significantly upregulated expression of key PA catabolic enzymes such as polyamine oxidase (PAO) and spermine oxidase (SMO). MDL-72,527, a specific inhibitor of PAO and SMO, decreased apoptotic potential of CDK inhibitors on HCT 116 cells. Moreover, transient silencing of PAO was also reduced prevented CDK inhibitor-induced apoptosis in HCT 116 cells. We conclude that the PA catabolic pathway, especially PAO, is a critical target for understanding the molecular mechanism of CDK inhibitor-induced apoptosis. PMID:23892915

  15. In vivo biodistribution, biocompatibility, and efficacy of sorafenib-loaded lipid-based nanosuspensions evaluated experimentally in cancer

    PubMed Central

    Yang, Shaomei; Zhang, Bo; Gong, Xiaowei; Wang, Tianqi; Liu, Yongjun; Zhang, Na

    2016-01-01

    Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. In this study, sorafenib-loaded lipid-based nanosuspensions (sorafenib-LNS) were first developed as an intravenous injectable formulation to increase the efficacy of sorafenib against HCC. LNS were used as nanocarriers for sorafenib owing to their desired features in increasing the solubility and dissolution velocity, improving the bioavailability of sorafenib. Sorafenib-LNS were prepared by nanoprecipitation and consisted of spherical particles with a uniform size distribution (164.5 nm, polydispersity index =0.202) and negative zeta potential (−11.0 mV). The drug loading (DL) was 10.55%±0.16%. Sorafenib-LNS showed higher in vitro cytotoxicity than sorafenib against HepG2 cells (P<0.05) and Bel-7402 cells (P<0.05). The in vivo biodistribution, biocompatibility, and antitumor efficacy of sorafenib-LNS were evaluated in H22-bearing liver cancer xenograft murine model. The results showed that sorafenib-LNS (9 mg/kg) exhibited significantly higher antitumor efficacy by reducing the tumor volume compared with the sorafenib oral group (18 mg/kg, P<0.05) and sorafenib injection group (9 mg/kg, P<0.05). Furthermore, the results of the in vivo biodistribution experiments demonstrated that sorafenib-LNS injected into H22 tumor-bearing mice exhibited increased accumulation in the tumor tissue, which was confirmed by in vivo imaging. In the current experimental conditions, sorafenib-LNS did not show significant toxicity both in vitro and in vivo. These results suggest that sorafenib-LNS are a promising nanomedicine for treating HCC. PMID:27307733

  16. Calcineurin inhibitors cyclosporine A and tacrolimus induce vascular inflammation and endothelial activation through TLR4 signaling.

    PubMed

    Rodrigues-Diez, Raquel; González-Guerrero, Cristian; Ocaña-Salceda, Carlos; Rodrigues-Diez, Raúl R; Egido, Jesús; Ortiz, Alberto; Ruiz-Ortega, Marta; Ramos, Adrián M

    2016-01-01

    The introduction of the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus greatly reduced the rate of allograft rejection, although their chronic use is marred by a range of side effects, among them vascular toxicity. In transplant patients, it is proved that innate immunity promotes vascular injury triggered by ischemia-reperfusion damage, atherosclerosis and hypertension. We hypothesized that activation of the innate immunity and inflammation may contribute to CNI toxicity, therefore we investigated whether TLR4 mediates toxic responses of CNIs in the vasculature. Cyclosporine and tacrolimus increased the production of proinflammatory cytokines and endothelial activation markers in cultured murine endothelial and vascular smooth muscle cells as well as in ex vivo cultures of murine aortas. CNI-induced proinflammatory events were prevented by pharmacological inhibition of TLR4. Moreover, CNIs were unable to induce inflammation and endothelial activation in aortas from TLR4(-/-) mice. CNI-induced cytokine and adhesion molecules synthesis in endothelial cells occurred even in the absence of calcineurin, although its expression was required for maximal effect through upregulation of TLR4 signaling. CNI-induced TLR4 activity increased O2(-)/ROS production and NF-κB-regulated synthesis of proinflammatory factors in cultured as well as aortic endothelial and VSMCs. These data provide new insight into the mechanisms associated with CNI vascular inflammation. PMID:27295076

  17. Targeting ER stress-induced autophagy overcomes BRAF inhibitor resistance in melanoma.

    PubMed

    Ma, Xiao-Hong; Piao, Sheng-Fu; Dey, Souvik; McAfee, Quentin; Karakousis, Giorgos; Villanueva, Jessie; Hart, Lori S; Levi, Samuel; Hu, Janice; Zhang, Gao; Lazova, Rossitza; Klump, Vincent; Pawelek, John M; Xu, Xiaowei; Xu, Wei; Schuchter, Lynn M; Davies, Michael A; Herlyn, Meenhard; Winkler, Jeffrey; Koumenis, Constantinos; Amaravadi, Ravi K

    2014-03-01

    Melanomas that result from mutations in the gene encoding BRAF often become resistant to BRAF inhibition (BRAFi), with multiple mechanisms contributing to resistance. While therapy-induced autophagy promotes resistance to a number of therapies, especially those that target PI3K/mTOR signaling, its role as an adaptive resistance mechanism to BRAFi is not well characterized. Using tumor biopsies from BRAF(V600E) melanoma patients treated either with BRAFi or with combined BRAF and MEK inhibition, we found that BRAFi-resistant tumors had increased levels of autophagy compared with baseline. Patients with higher levels of therapy-induced autophagy had drastically lower response rates to BRAFi and a shorter duration of progression-free survival. In BRAF(V600E) melanoma cell lines, BRAFi or BRAF/MEK inhibition induced cytoprotective autophagy, and autophagy inhibition enhanced BRAFi-induced cell death. Shortly after BRAF inhibitor treatment in melanoma cell lines, mutant BRAF bound the ER stress gatekeeper GRP78, which rapidly expanded the ER. Disassociation of GRP78 from the PKR-like ER-kinase (PERK) promoted a PERK-dependent ER stress response that subsequently activated cytoprotective autophagy. Combined BRAF and autophagy inhibition promoted tumor regression in BRAFi-resistant xenografts. These data identify a molecular pathway for drug resistance connecting BRAFi, the ER stress response, and autophagy and provide a rationale for combination approaches targeting this resistance pathway. PMID:24569374

  18. Inter-α inhibitor protein and its associated glycosaminoglycans protect against histone-induced injury

    PubMed Central

    Chaaban, Hala; Keshari, Ravi S.; Silasi-Mansat, Robert; Popescu, Narcis I.; Mehta-D’Souza, Padmaja; Lim, Yow-Pin

    2015-01-01

    Extracellular histones are mediators of tissue injury and organ dysfunction; therefore they constitute potential therapeutic targets in sepsis, inflammation, and thrombosis. Histone cytotoxicity in vitro decreases in the presence of plasma. Here, we demonstrate that plasma inter-α inhibitor protein (IAIP) neutralizes the cytotoxic effects of histones and decreases histone-induced platelet aggregation. These effects are mediated through the negatively charged glycosaminoglycans (GAGs) chondroitin sulfate and high-molecular-weight hyaluronan (HMW-HA) associated with IAIP. Cell surface anionic glycosaminoglycans heparan sulfate and HA protect the cells against histone-mediated damage in vitro. Surface plasmon resonance showed that both IAIP and HMW-HA directly bind to recombinant histone H4. In vivo neutralization of histones with IAIP and HMW-HA prevented histone-induced thrombocytopenia, bleeding, and lung microvascular thrombosis, decreased neutrophil activation, and averted histone-induced production of inflammatory cytokines and chemokines. IAIP and HMW-HA colocalized with histones in necrotic tissues and areas that displayed neutrophil extracellular traps. Increasing amounts of IAIP-histone complexes detected in the plasma of septic baboons correlated with increase in histones and/or nucleosomes and consumption of plasma IAIP. Our data suggest that IAIP, chondroitin sulfate, and HMW-HA are potential therapeutic agents to protect against histone-induced cytotoxicity, coagulopathy, systemic inflammation, and organ damage during inflammatory conditions such as sepsis and trauma. PMID:25631771

  19. Calcineurin inhibitors cyclosporine A and tacrolimus induce vascular inflammation and endothelial activation through TLR4 signaling

    PubMed Central

    Rodrigues-Diez, Raquel; González-Guerrero, Cristian; Ocaña-Salceda, Carlos; Rodrigues-Diez, Raúl R.; Egido, Jesús; Ortiz, Alberto; Ruiz-Ortega, Marta; Ramos, Adrián M.

    2016-01-01

    The introduction of the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus greatly reduced the rate of allograft rejection, although their chronic use is marred by a range of side effects, among them vascular toxicity. In transplant patients, it is proved that innate immunity promotes vascular injury triggered by ischemia-reperfusion damage, atherosclerosis and hypertension. We hypothesized that activation of the innate immunity and inflammation may contribute to CNI toxicity, therefore we investigated whether TLR4 mediates toxic responses of CNIs in the vasculature. Cyclosporine and tacrolimus increased the production of proinflammatory cytokines and endothelial activation markers in cultured murine endothelial and vascular smooth muscle cells as well as in ex vivo cultures of murine aortas. CNI-induced proinflammatory events were prevented by pharmacological inhibition of TLR4. Moreover, CNIs were unable to induce inflammation and endothelial activation in aortas from TLR4−/− mice. CNI-induced cytokine and adhesion molecules synthesis in endothelial cells occurred even in the absence of calcineurin, although its expression was required for maximal effect through upregulation of TLR4 signaling. CNI-induced TLR4 activity increased O2−/ROS production and NF-κB-regulated synthesis of proinflammatory factors in cultured as well as aortic endothelial and VSMCs. These data provide new insight into the mechanisms associated with CNI vascular inflammation. PMID:27295076

  20. The Na+/H+ exchange inhibitor HOE642 prevents stress-induced epithelial barrier dysfunction.

    PubMed

    Nowak, Peter; Blaheta, Roman; Schuller, Alina; Cinatl, Jindrich; Wimmer-Greinecker, Gerhard; Moritz, Anton; Scholz, Martin

    2004-08-01

    Recently, evidence has been obtained that the Na+/H+ exchange (NHE) inhibitor HOE642 may stabilize endothelial and epithelial barrier function in vivo. However, the underlying mechanisms are not known. Therefore, we studied the influence of HOE642 on the barrier function of the epithelial cell line CaCo2. The phorbolester phorbol 12-myristate 13-acetate (PMA) was used to induce hyperpermeability of the epithelial layer which was indirectly determined by measuring the transepithelial electrical resistance (TER). Confocal laser scan microscopy (LSM) served to analyze the intracellular localization of adherens and tight junction molecules. In five independent experiments we found that HOE642 increased TER in non-treated CaCo2 cells (control: 350 +/- 28 Omega/cm2; HOE642: 444 +/- 53 Omega/cm2) and prevented PMA-induced barrier dysfunction (PMA: 33 +/- 12 Omega/cm2; PMA plus HOE642: 496 +/- 47 Omega/cm2). LSM showed that HOE642 prevented the PMA-induced disassociation of the zonula adherens molecule beta-catenin from the cell membrane and the decreased expression of the zonula occludens molecule ZO-1. From our data we conclude that HOE642 may prevent stress-induced epithelial dysfunction by stabilization of cell membrane-associated junction molecules. PMID:15254761

  1. Attenuating Aβ1-42-induced toxicity by a novel acetylcholinesterase inhibitor.

    PubMed

    Mishra, N; Sasmal, D; Singh, K K

    2013-10-10

    We explored the attenuating effects of NP-9 on β-amyloid (Aβ) aggregation and amyloid-induced toxicity. NP-9 is a recently reported monoamine oxidase B (MAO-B), and acetylcholinesterase (AChE) inhibitor. In the present study, we found that NP-9 inhibited AChE activity in a dose-dependent manner with a maximal inhibition dose of 8 mg/kg, i.p. It inhibited Aβ aggregation, observed through thioflavin-T assay (IC50=60 μM) and scanning electron microscopy (S.E.M.) (no fibril formation). NP-9 has shown marked protection against scopolamine and Aβ1-42-induced memory impairments. It also minimized neuronal loss and amyloid plaque deposition in the brains of Aβ1-42-induced mice model. Therefore, NP-9 could be a promising lead molecule for AD, with effects against MAO-B, AChE, Aβ aggregation, and Aβ1-42 induced toxicity. PMID:23872389

  2. Deciphering the molecular and biologic processes that mediate histone deacetylase inhibitor-induced thrombocytopenia.

    PubMed

    Bishton, Mark J; Harrison, Simon J; Martin, Benjamin P; McLaughlin, Nicole; James, Chloé; Josefsson, Emma C; Henley, Katya J; Kile, Benjamin T; Prince, H Miles; Johnstone, Ricky W

    2011-03-31

    Histone deacetylase inhibitor (HDACI)-induced thrombocytopenia (TCP) is a major dose-limiting toxicity of this new class of drugs. Using preclinical models to study the molecular and biologic events that underpin this effect of HDACI, we found that C57BL/6 mice treated with both the HDAC1/2-selective HDACI romidepsin and the pan-HDACI panobinostat developed significant TCP. HDACI-induced TCP was not due to myelosuppression or reduced platelet lifespan, but to decreased platelet release from megakaryocytes. Cultured primary murine megakaryocytes showed reductions in proplatelet extensions after HDACI exposure and a dose-dependent increase in the phosphorylation of myosin light chain 2 (MLC2). Phosphorylation of MLC to phospho-MLC (pMLC) and subsequent proplatelet formation in megakaryocytes is regulated by the Rho-GTPase proteins Rac1, CDC42, and RhoA. Primary mouse megakaryocytes and the human megakaryoblastic cell line Meg-01 showed reductions in Rac1, CDC42, and RhoA protein levels after treatment with HDACIs. We were able to overcome HDACI-induced TCP by administering the mouse-specific thrombopoietin (TPO) mimetic AMP-4, which improved platelet numbers to levels similar to untreated controls. Our report provides the first detailed account of the molecular and biologic processes involved in HDACI-mediated TCP. Moreover, our preclinical studies provide evidence that dose-limiting TCP induced by HDACIs may be circumvented using a TPO mimetic. PMID:21292776

  3. Isoflurane-Induced Spatial Memory Impairment in Mice is Prevented by the Acetylcholinesterase Inhibitor Donepezil

    PubMed Central

    Wang, Beilei; Xu, Huan; Li, Wen; Chen, Jie; Wang, Xiangrui

    2011-01-01

    Although many studies have shown that isoflurane exposure impairs spatial memory in aged animals, there are no clinical treatments available to prevent this memory deficit. The anticholinergic properties of volatile anesthetics are a biologically plausible cause of cognitive dysfunction in elderly subjects. We hypothesized that pretreatment with the acetylcholinesterase inhibitor donepezil, which has been approved by the Food and Drug Administration (FDA) for the treatment of Alzheimer's disease, prevents isoflurane-induced spatial memory impairment in aged mice. In present study, eighteen-month-old mice were administered donepezil (5 mg/kg) or an equal volume of saline by oral gavage with a feeding needle for four weeks. Then the mice were exposed to isoflurane (1.2%) for six hours. Two weeks later, mice were subjected to the Morris water maze to examine the impairment of spatial memory after exposure to isoflurane. After the behavioral test, the mice were sacrificed, and the protein expression level of acetylcholinesterase (AChE), choline acetylase (ChAT) and α7 nicotinic receptor (α7-nAChR) were measured in the brain. Each group consisted of 12 mice. We found that isoflurane exposure for six hours impaired the spatial memory of the mice. Compared with the control group, isoflurane exposure dramatically decreased the protein level of ChAT, but not AChE or α7-nAChR. Donepezil prevented isoflurane-induced spatial memory impairments and increased ChAT levels, which were downregulated by isoflurane. In conclusions, pretreatment with the AChE inhibitor donepezil prevented isoflurane-induced spatial memory impairment in aged mice. The mechanism was associated with the upregulation of ChAT, which was decreased by isoflurane. PMID:22114680

  4. Isoflurane-induced spatial memory impairment in mice is prevented by the acetylcholinesterase inhibitor donepezil.

    PubMed

    Su, Diansan; Zhao, Yanxing; Wang, Beilei; Xu, Huan; Li, Wen; Chen, Jie; Wang, Xiangrui

    2011-01-01

    Although many studies have shown that isoflurane exposure impairs spatial memory in aged animals, there are no clinical treatments available to prevent this memory deficit. The anticholinergic properties of volatile anesthetics are a biologically plausible cause of cognitive dysfunction in elderly subjects. We hypothesized that pretreatment with the acetylcholinesterase inhibitor donepezil, which has been approved by the Food and Drug Administration (FDA) for the treatment of Alzheimer's disease, prevents isoflurane-induced spatial memory impairment in aged mice. In present study, eighteen-month-old mice were administered donepezil (5 mg/kg) or an equal volume of saline by oral gavage with a feeding needle for four weeks. Then the mice were exposed to isoflurane (1.2%) for six hours. Two weeks later, mice were subjected to the Morris water maze to examine the impairment of spatial memory after exposure to isoflurane. After the behavioral test, the mice were sacrificed, and the protein expression level of acetylcholinesterase (AChE), choline acetylase (ChAT) and α7 nicotinic receptor (α7-nAChR) were measured in the brain. Each group consisted of 12 mice. We found that isoflurane exposure for six hours impaired the spatial memory of the mice. Compared with the control group, isoflurane exposure dramatically decreased the protein level of ChAT, but not AChE or α7-nAChR. Donepezil prevented isoflurane-induced spatial memory impairments and increased ChAT levels, which were downregulated by isoflurane. In conclusions, pretreatment with the AChE inhibitor donepezil prevented isoflurane-induced spatial memory impairment in aged mice. The mechanism was associated with the upregulation of ChAT, which was decreased by isoflurane. PMID:22114680

  5. B-Raf inhibitors induce epithelial differentiation in BRAF-mutant colorectal cancer cells.

    PubMed

    Herr, Ricarda; Köhler, Martin; Andrlová, Hana; Weinberg, Florian; Möller, Yvonne; Halbach, Sebastian; Lutz, Lisa; Mastroianni, Justin; Klose, Martin; Bittermann, Nicola; Kowar, Silke; Zeiser, Robert; Olayioye, Monilola A; Lassmann, Silke; Busch, Hauke; Boerries, Melanie; Brummer, Tilman

    2015-01-01

    BRAF mutations are associated with aggressive, less-differentiated and therapy-resistant colorectal carcinoma. However, the underlying mechanisms for these correlations remain unknown. To understand how oncogenic B-Raf contributes to carcinogenesis, in particular to aspects other than cellular proliferation and survival, we generated three isogenic human colorectal carcinoma cell line models in which we can dynamically modulate the expression of the B-Raf(V600E) oncoprotein. Doxycyclin-inducible knockdown of endogenous B-Raf(V600E) decreases cellular motility and invasion in conventional and three-dimensional (3D) culture, whereas it promotes cell-cell contacts and induces various hallmarks of differentiated epithelia. Importantly, all these effects are recapitulated by B-Raf (PLX4720, vemurafenib, and dabrafenib) or MEK inhibitors (trametinib). Surprisingly, loss of B-Raf(V600E) in HT29 xenografts does not only stall tumor growth, but also induces glandular structures with marked expression of CDX2, a tumor-suppressor and master transcription factor of intestinal differentiation. By performing the first transcriptome profiles of PLX4720-treated 3D cultures of HT29 and Colo-205 cells, we identify several upregulated genes linked to epithelial differentiation and effector functions, such as claudin-1, a Cdx-2 target gene encoding a critical tight junction component. Thereby, we provide a mechanism for the clinically observed correlation between mutant BRAF and the loss of Cdx-2 and claudin-1. PLX4720 also suppressed several metastasis-associated transcripts that have not been implicated as targets, effectors or potential biomarkers of oncogenic B-Raf signaling so far. Together, we identify a novel facet of clinically applied B-Raf or MEK inhibitors by showing that they promote cellular adhesion and differentiation of colorectal carcinoma cells. PMID:25381152

  6. Adjuvant sorafenib in hepatocellular carcinoma: A cautionary comment of STORM trial

    PubMed Central

    Zhong, Jian-Hong; Du, Xue-Ke; Xiang, Bang-De; Li, Le-Qun

    2016-01-01

    Recurrence rate of hepatocellular carcinoma (HCC) is very high even after curative surgery, and no postoperative therapies have been definitively shown to prevent HCC recurrence. Sorafenib is proved to be effective for advanced HCC by two large randomized controlled trials in 2008 and 2009. Therefore it stands to reason to expect that adjuvant sorafenib may improve post-surgery outcomes of patients with HCC. However, many questions still exist about the value of sorafenib for patients with HCC after surgery or transarterial chemoembolization. In this editorial, we complehensively reviewed the safety and efficacy of adjuvant sorafenib for patients with hepatocellar carcinoma after surgery or transarterial chemoembolization. We emphasized the positive and negative role of sorafenib.

  7. Fulminant hepatitis in a patient with hepatocellular carcinoma related to nonalcoholic steatohepatitis treated with sorafenib.

    PubMed

    Brandi, Giovanni; De Lorenzo, Stefania; Di Girolamo, Stefania; Bellentani, Stefano; Saccoccio, Gioconda; Biasco, Guido

    2015-01-01

    We describe a case of acute liver failure in a patient with advanced hepatocellular carcinoma related to nonalcoholic steatohepatitis during sorafenib treatment. A 74-year-old man with diabetes mellitus and hypertension was diagnosed with hepatocellular carcinoma associated with fatty liver. Three weeks after sorafenib therapy, at Eastern Cooperative Oncology Group performance status 3, he developed jaundice, general weakness, flapping tremor, nausea, and anorexia. Sorafenib was stopped: laboratory tests showed a relevant elevation of transaminases suggesting diagnosis of acute hepatitis. During hospital admission, the patient died of liver failure. Sorafenib is the first successful target therapy effective for advanced hepatocellular carcinoma. The most common adverse events are fatigue, hand-foot skin reaction, skin rash/desquamation, diarrhea, and hypertension, whereas liver dysfunction is uncommon. To our knowledge, this is the first patient reported in the literature with hepatocellular carcinoma related to nonalcoholic steatohepatitis who died of rapid worsening of liver function during sorafenib treatment. PMID:25702656

  8. Adjuvant sorafenib in hepatocellular carcinoma: A cautionary comment of STORM trial.

    PubMed

    Zhong, Jian-Hong; Du, Xue-Ke; Xiang, Bang-De; Li, Le-Qun

    2016-08-18

    Recurrence rate of hepatocellular carcinoma (HCC) is very high even after curative surgery, and no postoperative therapies have been definitively shown to prevent HCC recurrence. Sorafenib is proved to be effective for advanced HCC by two large randomized controlled trials in 2008 and 2009. Therefore it stands to reason to expect that adjuvant sorafenib may improve post-surgery outcomes of patients with HCC. However, many questions still exist about the value of sorafenib for patients with HCC after surgery or transarterial chemoembolization. In this editorial, we complehensively reviewed the safety and efficacy of adjuvant sorafenib for patients with hepatocellar carcinoma after surgery or transarterial chemoembolization. We emphasized the positive and negative role of sorafenib. PMID:27621761

  9. Microinjection of histone deacetylase inhibitor into the ventrolateral orbital cortex potentiates morphine induced behavioral sensitization.

    PubMed

    Wei, Lai; Zhu, Yuan-Mei; Zhang, Yu-Xiang; Liang, Feng; Barry, Devin M; Gao, Hong-Yu; Li, Tao; Huo, Fu-Quan; Yan, Chun-Xia

    2016-09-01

    Accumulating evidence indicates that epigenetic regulation, such as changes in histone modification in reward-related brain regions, contributes to the memory formation of addiction to opiates and psychostimulants. Our recent results suggested that the ventrolateral orbital cortex (VLO) is involved in the memories of stress and drug addiction. Since addiction and stress memories share some common pathways, the present study was designed to investigate the role of histone deacetylase (HDAC) activity in the VLO during morphine induced-behavioral sensitization. Rats received a single exposure to morphine for establishing the behavioral sensitization model. The effect of HDAC activity in the VLO in morphine induced-behavioral sensitization was examined by microinjection of HDAC inhibitor Trichostatin A (TSA). Furthermore, the protein expression levels of extracellular signal-regulated kinase (ERK) and phosphorylated ERK (p-ERK), histone H3 lysine 9 acetylation (aceH3K9) and brain-derived neurotrophic factor (BDNF) in the VLO in morphine-induced behavioral sensitization were examined. The results showed that the bilateral VLO lesions suppressed the expression phase, but not the developmental phase of morphine-induced behavioral sensitization. Microinjection of TSA into the VLO significantly increased both the development and expression phases. Moreover, the protein levels of p-ERK, aceH3K9 and BDNF except ERK in the VLO were significantly upregulated in morphine-treated rats in the expression phase. These effects were further strengthened by intra-VLO injection of TSA. Our findings suggest that HDAC activity in the VLO could potentiate morphine-induced behavioral sensitization. The upregulated expression of p-ERK, aceH3K9 and BDNF in the VLO might be the underlying mechanism of histone acetylation enhancing the morphine-induced behavioral sensitization. PMID:27312092

  10. Inhibition of chlorine-induced lung injury by the type 4 phosphodiesterase inhibitor rolipram

    SciTech Connect

    Chang, Weiyuan; Chen, Jing; Schlueter, Connie F.; Rando, Roy J.; Pathak, Yashwant V.; Hoyle, Gary W.

    2012-09-01

    Chlorine is a highly toxic respiratory irritant that when inhaled causes epithelial cell injury, alveolar-capillary barrier disruption, airway hyperreactivity, inflammation, and pulmonary edema. Chlorine is considered a chemical threat agent, and its release through accidental or intentional means has the potential to result in mass casualties from acute lung injury. The type 4 phosphodiesterase inhibitor rolipram was investigated as a rescue treatment for chlorine-induced lung injury. Rolipram inhibits degradation of the intracellular signaling molecule cyclic AMP. Potential beneficial effects of increased cyclic AMP levels include inhibition of pulmonary edema, inflammation, and airway hyperreactivity. Mice were exposed to chlorine (whole body exposure, 228–270 ppm for 1 h) and were treated with rolipram by intraperitoneal, intranasal, or intramuscular (either aqueous or nanoemulsion formulation) delivery starting 1 h after exposure. Rolipram administered intraperitoneally or intranasally inhibited chlorine-induced pulmonary edema. Minor or no effects were observed on lavage fluid IgM (indicative of plasma protein leakage), KC (Cxcl1, neutrophil chemoattractant), and neutrophils. All routes of administration inhibited chlorine-induced airway hyperreactivity assessed 1 day after exposure. The results of the study suggest that rolipram may be an effective rescue treatment for chlorine-induced lung injury and that both systemic and targeted administration to the respiratory tract were effective routes of delivery. -- Highlights: ► Chlorine causes lung injury when inhaled and is considered a chemical threat agent. ► Rolipram inhibited chlorine-induced pulmonary edema and airway hyperreactivity. ► Post-exposure rolipram treatments by both systemic and local delivery were effective. ► Rolipram shows promise as a rescue treatment for chlorine-induced lung injury.

  11. Immune checkpoint inhibitors enhance cytotoxicity of cytokine-induced killer cells against human myeloid leukaemic blasts.

    PubMed

    Poh, Su Li; Linn, Yeh Ching

    2016-05-01

    We studied whether blockade of inhibitory receptors on cytokine-induced killer (CIK) cells by immune checkpoint inhibitors could increase its anti-tumour potency against haematological malignancies. CIK cultures were generated from seven normal donors and nine patients with acute myeloid leukaemia (AML), acute lymphoblastic leukaemia (ALL) or multiple myeloma (MM). The inhibitory receptors B and T lymphocyte attenuator, CD200 receptor, lymphocyte activation gene-3 (LAG-3) and T cell immunoglobulin and mucin-domain-containing-3 (TIM-3) were present at variable percentages in most CIK cultures, while cytotoxic T lymphocyte-associated protein 4 (CTLA-4), programmed death-1 (PD-1) and killer cell immunoglobulin-like receptors (KIR2DL1/2/3) were expressed at low level in most cultures. Without blockade, myeloid leukaemia cells were susceptible to autologous and allogeneic CIK-mediated cytotoxicity. Blockade of KIR, LAG-3, PD-1 and TIM-3 but not CTLA-4 resulted in remarkable increase in killing against these targets, even in those with poor baseline cytotoxicity. ALL and MM targets were resistant to CIK-mediated cytotoxicity, and blockade of receptors did not increase cytotoxicity to a meaningful extent. Combination of inhibitors against two receptors did not further increase cytotoxicity. Interestingly, potentiation of CIK killing by blocking antibodies was not predicted by expression of receptors on CIK and their respective ligands on the targets. Compared to un-activated T and NK cells, blockade potentiated the cytotoxicity of CIK cells to a greater degree and at a lower E:T ratio, but without significant increase in cytotoxicity against normal white cell. Our findings provide the basis for clinical trial combining autologous CIK cells with checkpoint inhibitors for patients with AML. PMID:26961084

  12. Amelioration of Acute Kidney Injury in Lipopolysaccharide-Induced Systemic Inflammatory Response Syndrome by an Aldose Reductase Inhibitor, Fidarestat

    PubMed Central

    Takahashi, Kazunori; Mizukami, Hiroki; Kamata, Kosuke; Inaba, Wataru; Kato, Noriaki; Hibi, Chihiro; Yagihashi, Soroku

    2012-01-01

    Background Systemic inflammatory response syndrome is a fatal disease because of multiple organ failure. Acute kidney injury is a serious complication of systemic inflammatory response syndrome and its genesis is still unclear posing a difficulty for an effective treatment. Aldose reductase (AR) inhibitor is recently found to suppress lipopolysaccharide (LPS)-induced cardiac failure and its lethality. We studied the effects of AR inhibitor on LPS-induced acute kidney injury and its mechanism. Methods Mice were injected with LPS and the effects of AR inhibitor (Fidarestat 32 mg/kg) before or after LPS injection were examined for the mortality, severity of renal failure and kidney pathology. Serum concentrations of cytokines (interleukin-1β, interleukin-6, monocyte chemotactic protein-1 and tumor necrosis factor-α) and their mRNA expressions in the lung, liver, spleen and kidney were measured. We also evaluated polyol metabolites in the kidney. Results Mortality rate within 72 hours was significantly less in LPS-injected mice treated with AR inhibitor both before (29%) and after LPS injection (40%) than untreated mice (90%). LPS-injected mice showed marked increases in blood urea nitrogen, creatinine and cytokines, and AR inhibitor treatment suppressed the changes. LPS-induced acute kidney injury was associated with vacuolar degeneration and apoptosis of renal tubular cells as well as infiltration of neutrophils and macrophages. With improvement of such pathological findings, AR inhibitor treatment suppressed the elevation of cytokine mRNA levels in multiple organs and renal sorbitol accumulation. Conclusion AR inhibitor treatment ameliorated LPS-induced acute kidney injury, resulting in the lowered mortality. PMID:22253906

  13. Hesperetin, a Selective Phosphodiesterase 4 Inhibitor, Effectively Suppresses Ovalbumin-Induced Airway Hyperresponsiveness without Influencing Xylazine/Ketamine-Induced Anesthesia

    PubMed Central

    Shih, Chung-Hung; Lin, Ling-Hung; Hsu, Hsin-Te; Wang, Kuo-Hsien; Lai, Chi-Yin; Chen, Chien-Ming; Ko, Wun-Chang

    2012-01-01

    Hesperetin, a selective phosphodiesterase (PDE)4 inhibitor, is present in the traditional Chinese medicine, “Chen Pi.” Therefore, we were interested in investigating its effects on ovalbumin- (OVA-) induced airway hyperresponsiveness, and clarifying its rationale for ameliorating asthma and chronic obstructive pulmonary disease (COPD). Hesperetin was revealed to have a therapeutic (PDE4H/PDE4L) ratio of >11. Hesperetin (10 ~ 30 μmol/kg, intraperitoneally (i.p.)) dose-dependently and significantly attenuated the airway hyperresponsiveness induced by methacholine. It also significantly suppressed the increases in total inflammatory cells, macrophages, lymphocytes, neutrophils, and eosinophils, and levels of cytokines, including interleukin (IL)-2, IL-4, IL-5, interferon-γ, and tumor necrosis factor-α in bronchoalveolar lavage fluid (BALF). It dose-dependently and significantly suppressed total and OVA-specific immunoglobulin E levels in the BALF and serum. However, hesperetin did not influence xylazine/ketamine-induced anesthesia, suggesting that hesperetin has few or no emetic effects. In conclusion, the rationales for ameliorating allergic asthma and COPD by hesperetin are anti-inflammation, immunoregulation, and bronchodilation. PMID:22454667

  14. Regulation of Multidrug Resistance Proteins by Genistein in a Hepatocarcinoma Cell Line: Impact on Sorafenib Cytotoxicity

    PubMed Central

    Rigalli, Juan Pablo; Ciriaci, Nadia; Arias, Agostina; Ceballos, María Paula; Villanueva, Silvina Stella Maris; Luquita, Marcelo Gabriel; Mottino, Aldo Domingo; Ghanem, Carolina Inés; Catania, Viviana Alicia; Ruiz, María Laura

    2015-01-01

    Hepatocellular carcinoma (HCC) is the fifth most frequent cancer worldwide. Sorafenib is the only drug available that improves the overall survival of HCC patients. P-glycoprotein (P-gp), Multidrug resistance-associated proteins 2 and 3 (MRP2 and 3) and Breast cancer resistance protein (BCRP) are efflux pumps that play a key role in cancer chemoresistance. Their modulation by dietary compounds may affect the intracellular accumulation and therapeutic efficacy of drugs that are substrates of these transporters. Genistein (GNT) is a phytoestrogen abundant in soybean that exerts its genomic effects through Estrogen-Receptors and Pregnane-X-Receptor (PXR), which are involved in the regulation of the above-mentioned transporters. We evaluated the effect of GNT on the expression and activity of P-gp, MRP2, MRP3 and BCRP in HCC-derived HepG2 cells. GNT (at 1.0 and 10 μM) increased P-gp and MRP2 protein expression and activity, correlating well with an increased resistance to sorafenib cytotoxicity as detected by the methylthiazole tetrazolium (MTT) assay. GNT induced P-gp and MRP2 mRNA expression at 10 but not at 1.0 μM concentration suggesting a different pattern of regulation depending on the concentration. Induction of both transporters by 1.0 μM GNT was prevented by cycloheximide, suggesting translational regulation. Downregulation of expression of the miR-379 by GNT could be associated with translational regulation of MRP2. Silencing of PXR abolished P-gp induction by GNT (at 1.0 and 10 μM) and MRP2 induction by GNT (only at 10 μM), suggesting partial mediation of GNT effects by PXR. Taken together, the data suggest the possibility of nutrient-drug interactions leading to enhanced chemoresistance in HCC when GNT is ingested with soy rich diets or dietary supplements. PMID:25781341

  15. Concurrent versus Sequential Sorafenib Therapy in Combination with Radiation for Hepatocellular Carcinoma

    PubMed Central

    Chettiar, Sivarajan T.; Aziz, Khaled; Gajula, Rajendra P.; Williams, Russell D.; Kumar, Rachit; Taparra, Kekoa; Zeng, Jing; Cades, Jessica A.; Velarde, Esteban; Menon, Siddharth; Geschwind, Jean F.; Cosgrove, David; Pawlik, Timothy M.; Maitra, Anirban; Wong, John; Hales, Russell K.; Torbenson, Michael S.; Herman, Joseph M.; Tran, Phuoc T.

    2013-01-01

    Sorafenib (SOR) is the only systemic agent known to improve survival for hepatocellular carcinoma (HCC). However, SOR prolongs survival by less than 3 months and does not alter symptomatic progression. To improve outcomes, several phase I-II trials are currently examining SOR with radiation (RT) for HCC utilizing heterogeneous concurrent and sequential treatment regimens. Our study provides preclinical data characterizing the effects of concurrent versus sequential RT-SOR on HCC cells both in vitro and in vivo. Concurrent and sequential RT-SOR regimens were tested for efficacy among 4 HCC cell lines in vitro by assessment of clonogenic survival, apoptosis, cell cycle distribution, and γ-H2AX foci formation. Results were confirmed in vivo by evaluating tumor growth delay and performing immunofluorescence staining in a hind-flank xenograft model. In vitro, concurrent RT-SOR produced radioprotection in 3 of 4 cell lines, whereas sequential RT-SOR produced decreased colony formation among all 4. Sequential RT-SOR increased apoptosis compared to RT alone, while concurrent RT-SOR did not. Sorafenib induced reassortment into less radiosensitive phases of the cell cycle through G1-S delay and cell cycle slowing. More double-strand breaks (DSBs) persisted 24 h post-irradiation for RT alone versus concurrent RT-SOR. In vivo, sequential RT-SOR produced the greatest tumor growth delay, while concurrent RT-SOR was similar to RT alone. More persistent DSBs were observed in xenografts treated with sequential RT-SOR or RT alone versus concurrent RT-SOR. Sequential RT-SOR additionally produced a greater reduction in xenograft tumor vascularity and mitotic index than either concurrent RT-SOR or RT alone. In conclusion, sequential RT-SOR demonstrates greater efficacy against HCC than concurrent RT-SOR both in vitro and in vivo. These results may have implications for clinical decision-making and prospective trial design. PMID:23762417

  16. Integrated Analysis of Drug-Induced Gene Expression Profiles Predicts Novel hERG Inhibitors

    PubMed Central

    Babcock, Joseph J.; Du, Fang; Xu, Kaiping; Wheelan, Sarah J.; Li, Min

    2013-01-01

    Growing evidence suggests that drugs interact with diverse molecular targets mediating both therapeutic and toxic effects. Prediction of these complex interactions from chemical structures alone remains challenging, as compounds with different structures may possess similar toxicity profiles. In contrast, predictions based on systems-level measurements of drug effect may reveal pharmacologic similarities not evident from structure or known therapeutic indications. Here we utilized drug-induced transcriptional responses in the Connectivity Map (CMap) to discover such similarities among diverse antagonists of the human ether-à-go-go related (hERG) potassium channel, a common target of promiscuous inhibition by small molecules. Analysis of transcriptional profiles generated in three independent cell lines revealed clusters enriched for hERG inhibitors annotated using a database of experimental measurements (hERGcentral) and clinical indications. As a validation, we experimentally identified novel hERG inhibitors among the unannotated drugs in these enriched clusters, suggesting transcriptional responses may serve as predictive surrogates of cardiotoxicity complementing existing functional assays. PMID:23936032

  17. [Vasoactive prostanoids and inhibitors of blood coagulation in pregnancy-induced hypertension].

    PubMed

    Peterseim, H; Kemkes-Matthes, B

    1994-01-01

    The aim of the present study was to investigate the occurrence of changes in the plasma levels of vasoactive prostanoids and inhibitors of blood coagulation in normal pregnancy and in cases of pregnancy induced hypertension. Levels of the coagulation inhibitors antithrombin III, protein C, Protein S as well as the prostaglandin metabolites thromboxane B2 and 6-oxo-prostaglandin F1 alpha were measured between 13 and 37 weeks gestation in 36 primigravidae. In 8 of the examined patients persistently raised blood pressure values of 140/90 and above were measured after 20 weeks of gestation. Our results indicated that an imbalance of vasoactive prostanoids may precede the appearance of clinical symptoms of PIH. The determination of coagulation factors before blood pressure is elevated has no predictive value regarding the later development of PIH. The reduced levels of protein C associated with our PIH group are considered to be the result of an activated coagulation followed by consumption of clotting factors. Reduced measured levels of protein S in normotensive as well as hypertensive pregnancies offer an explanation for the increased risk of thromboembolic disease. This increased susceptibility to thromboembolic disorders is further enhanced by the altered balance between the platelet aggregator and vasoconstrictor thromboxane A2 and its antagonist prostacyclin. PMID:8048287

  18. Chemically Accessible Hsp90 Inhibitor That Does Not Induce a Heat Shock Response

    PubMed Central

    2014-01-01

    Recent cancer therapies have focused on targeting biology networks through a single regulatory protein. Heat shock protein 90 (hsp90) is an ideal oncogenic target as it regulates over 400 client proteins and cochaperones. However, clinical inhibitors of hsp90 have had limited success; the primary reason being that they induce a heat shock response. We describe the synthesis and biological evaluation of a new hsp90 inhibitor, SM253. The previous generation on which SM253 is based (SM145) has poor overall synthetic yields, low solubility, and micromolar cytotoxicity. By comparison SM253 has relatively high overall yields, good aqueous solubility, and is more cytotoxic than its parent compound. Verification that hsp90 is SM253’s target was accomplished using pull-down and protein folding assays. SM253 is superior to both SM145 and the clinical candidate 17-AAG as it decreases proteins related to the heat shock response by 2-fold, versus a 2–4-fold increase observed when cells are treated with 17-AAG. PMID:25050163

  19. Activation of c-Jun predicts a poor response to sorafenib in hepatocellular carcinoma: Preliminary Clinical Evidence

    PubMed Central

    Chen, Wei; Xiao, Weikai; Zhang, Kunsong; Yin, Xiaoyu; Lai, Jiaming; Liang, Lijian; Chen, Dong

    2016-01-01

    We determined the mitogen-activated protein kinase (MAPK) gene expression profile of acquired resistance in sorafenib-sensitive hepatocellular carcinoma (HCC) cells and aimed to identify c-Jun as an important molecule mediating the efficacy of sorafenib. Differences in gene expression of the MAPK signaling between untreated and sorafenib-treated HCC cell lines were investigated using real-time polymerase chain reaction array. Western blot and real-time PCR further evaluated the expression of c-Jun. Pathological specimens from 50 patients with advanced HCC were collected to measure p-c-Jun expression. Sorafenib-resistant HCC cells demonstrated greater levels of basal c-Jun mRNA and protein compared with sorafenib-sensitive HCC cells. Sorafenib activated p-c-Jun in a dose- and time-dependent manner in PLC/PRF/5 and MHCC97H cell lines. Decreased expression levels of 6 genes after sorafenib treatment suggested a robust inhibitory impact of sorafenib on MAPK signaling in HCC cells. c-Jun and p-c-Jun expression levels were inversely correlated with the efficacy of sorafenib; a high expression level of p-c-Jun was associated with resistance to sorafenib and poor overall survival in patients with clinical HCC. p-c-Jun may act as a biomarker for predicting responses of sorafenib treatment, thus advocating targeting of JNK/c-Jun signaling as an optimal therapeutic strategy in a subset of HCC. PMID:26964667

  20. Fisetin, a dietary flavonoid, augments the anti-invasive and anti-metastatic potential of sorafenib in melanoma

    PubMed Central

    Pal, Harish C.; Diamond, Ariana C.; Strickland, Leah R.; Kappes, John C.; Katiyar, Santosh K.; Elmets, Craig A.; Athar, Mohammad; Afaq, Farrukh

    2016-01-01

    Melanoma is the most aggressive and deadly form of cutaneous neoplasm due to its propensity to metastasize. Oncogenic BRAF drives sustained activation of the BRAF/MEK/ERK (MAPK) pathway and cooperates with PI3K/AKT/mTOR (PI3K) signaling to induce epithelial to mesenchymal transition (EMT), leading to cell invasion and metastasis. Therefore, targeting these pathways is a promising preventive/therapeutic strategy. We have shown that fisetin, a flavonoid, reduces human melanoma cell invasion by inhibiting EMT. In addition, fisetin inhibited melanoma cell proliferation and tumor growth by downregulating the PI3K pathway. In this investigation, we aimed to determine whether fisetin can potentiate the anti-invasive and anti-metastatic effects of sorafenib in BRAF-mutated melanoma. We found that combination treatment (fisetin + sorafenib) more effectively reduced the migration and invasion of BRAF-mutated melanoma cells both in vitro and in raft cultures compared to individual agents. Combination treatment also effectively inhibited EMT as observed by a decrease in N-cadherin, vimentin and fibronectin and an increase in E-cadherin both in vitro and in xenograft tumors. Furthermore, combination therapy effectively inhibited Snail1, Twist1, Slug and ZEB1 protein expression compared to monotherapy. The expression of MMP-2 and MMP-9 in xenograft tumors was further reduced in combination treatment compared to individual agents. Bioluminescent imaging of athymic mice, intravenously injected with stably transfected CMV-luciferase-ires-puromycin. T2A.EGFP-tagged A375 melanoma cells, demonstrated fewer lung metastases following combination treatment versus monotherapy. Our findings demonstrate that fisetin potentiates the anti-invasive and anti-metastatic effects of sorafenib. Our data suggest that fisetin may be a worthy adjuvant chemotherapy for the management of melanoma. PMID:26517521

  1. Can Exercise Ameliorate Aromatase Inhibitor-Induced Cognitive Decline in Breast Cancer Patients?

    PubMed

    Li, Cuicui; Zhou, Chenglin; Li, Rena

    2016-08-01

    Aromatase inhibitors (AIs) have been commonly used as an effective adjuvant therapy in treatment of breast cancer, especially for menopausal women with estrogen receptor-positive breast cancer. Due to the nature of aromatase, the key enzyme for endogenous estrogen synthesis, inhibitory of aromatase-induced side effects, such as cognitive impairment has been reported in both human and animal studies. While extensive evidence suggested that physical exercises can improve learning and memory activity and even prevent age-related cognitive decline, basic research revealed some common pathways between exercise and estrogen signaling that affected cognitive function. This review draws on clinical and basic studies to assess the potential impact of exercise in cognitive function from women treated with AIs for breast cancer and explore the potential mechanism and effects of exercise on estrogen-related cognition. PMID:26223800

  2. Proton-pump inhibitor-induced hypomagnesemia: Current research and proposed mechanisms

    PubMed Central

    William, Jeffrey H; Danziger, John

    2016-01-01

    Since the early reports nearly a decade ago, proton-pump inhibitor-induced hypomagnesemia (PPIH) has become a well-recognized phenomenon. While many observational studies in the inpatient and outpatient populations have confirmed the association of PPI exposure and serum magnesium concentrations, there are no prospective, controlled studies to support causation. Molecular mechanisms of magnesium transporters, including the pH-dependent regulation of transient receptor potential melastatin-6 transporters in the colonic enterocyte, have been proposed to explain the effect of PPIs on magnesium reabsorption, but may be a small part of a more complicated interplay of molecular biology, pharmacology, and genetic predisposition. This review explores the current state of research in the field of PPIH and the proposed mechanisms of this effect. PMID:26981439

  3. MK2 inhibitor reduces alkali burn-induced inflammation in rat cornea

    PubMed Central

    Chen, Yanfeng; Yang, Wenzhao; Zhang, Xiaobo; Yang, Shu; Peng, Gao; Wu, Ting; Zhou, Yueping; Huang, Caihong; Reinach, Peter S.; Li, Wei; Liu, Zuguo

    2016-01-01

    MK2 activation by p38 MAPK selectively induces inflammation in various diseases. We determined if a MK2 inhibitor (MK2i), improves cornea wound healing by inhibiting inflammation caused by burning rat corneas with alkali. Our study, for the first time, demonstrated that MK2i inhibited alkali burn-induced MK2 activation as well as rises in inflammation based on: a) blunting rises in inflammatory index, inflammatory cell infiltration, ED1+ macrophage and PMN+ neutrophil infiltration; b) suppressing IL-6 and IL-1β gene expression along with those of macrophage inflammatory protein-1α (MIP-1α), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1); c) reducing angiogenic gene expression levels and neovascularization (NV) whereas anti-angiogenic PEDF levels increased. In addition, this study found that MK2i did not affect human corneal epithelial cell (HCEC) proliferation and migration and had no detectable side effects on ocular surface integrity. Taken together, MK2i selectively inhibited alkali burn-induced corneal inflammation by blocking MK2 activation, these effects have clinical relevance in the treatment of inflammation related ocular surface diseases. PMID:27329698

  4. FK506, a calcineurin inhibitor, prevents cadmium-induced testicular toxicity in mice.

    PubMed

    Martin, Lisa Joy; Chen, Haiyan; Liao, Xiaoyan; Allayee, Hooman; Shih, Diana Mouhan; Lee, Grace Sangeun; Hovland, David Norman; Robbins, Wendie Anne; Carnes, Kay; Hess, Rex Allen; Lusis, Aldons Jake; Collins, Michael David

    2007-12-01

    Cadmium, a ubiquitous environmental contaminant, damages several major organs in humans and other mammals. The molecular mechanisms for damage are not known. At high doses (5 mg/kg cadmium chloride or higher), testicular damage in mice, rats, and other rodents includes interstitial edema, hemorrhage, and changes in the seminiferous tubules affecting spermatogenesis. Necrosis is evident by 48 h. The goal of this study was to fine map and identify the cdm gene, a gene that when mutated prevents cadmium-induced testicular toxicity in mouse strains with a mutation in this gene. A serine-threonine phosphatase, calcineurin (CN), subunit A, alpha isoform (Ppp3ca), was one of the seven candidates in the cdm region that was narrowed from 5.6 to 2.0 Mb on mouse chromosome 3. An inhibitor of CN, the immunosuppressant, FK506, prevented cadmium-induced testicular damage in five pathological categories, including vascular endothelial and seminiferous epithelial endpoints. Inductively coupled plasma-mass spectrometry revealed that FK506 protected without lowering the amount of cadmium in the testes. Ppp3ca(-/-) mice were investigated but were found to exhibit endogenous testicular abnormalities, making them an inappropriate model for determining whether the inactivation of the Ppp3ca gene would afford protection from cadmium-induced testicular toxicity. The protection afforded by FK506, found by the current study, indicated that CN is likely to be important in the mechanism of cadmium toxicity in the testis and possibly other organs. PMID:17785681

  5. A Receptor Tyrosine Kinase Inhibitor, Dovitinib (TKI-258), Enhances BMP-2-Induced Osteoblast Differentiation In Vitro.

    PubMed

    Lee, Yura; Bae, Kyoung Jun; Chon, Hae Jung; Kim, Seong Hwan; Kim, Soon Ae; Kim, Jiyeon

    2016-05-31

    Dovitinib (TKI258) is a small molecule multi-kinase inhibitor currently in clinical phase I/II/III development for the treatment of various types of cancers. This drug has a safe and effective pharmacokinetic/pharmacodynamic profile. Although dovitinib can bind several kinases at nanomolar concentrations, there are no reports relating to osteoporosis or osteoblast differentiation. Herein, we investigated the effect of dovitinib on human recombinant bone morphogenetic protein (BMP)-2-induced osteoblast differentiation in a cell culture model. Dovitinib enhanced the BMP-2-induced alkaline phosphatase (ALP) induction, which is a representative marker of osteoblast differentiation. Dovitinib also stimulated the translocation of phosphorylated Smad1/5/8 into the nucleus and phosphorylation of mitogen-activated protein kinases, including ERK1/2 and p38. In addition, the mRNA expression of BMP-4, BMP-7, ALP, and OCN increased with dovitinib treatment. Our results suggest that dovitinib has a potent stimulating effect on BMP-2-induced osteoblast differentiation and this existing drug has potential for repositioning in the treatment of bone-related disorders. PMID:27025387

  6. Effects of a Soluble Epoxide Hydrolase Inhibitor on Lipopolysaccharide-Induced Acute Lung Injury in Mice

    PubMed Central

    Yang, Liu-Qing; Ma, Yong-Bo

    2016-01-01

    Objectives Inflammation plays a key role in the pathogenesis of acute lung injury (ALI). Soluble epoxide hydrolase (sEH) is suggested as a vital pharmacologic target for inflammation. In this study, we determined whether a sEH inhibitor, AUDA, exerts lung protection in lipopolysaccharide (LPS)-induced ALI in mice. Methods Male BALB/c mice were randomized to receive AUDA or vehicle intraperitoneal injection 4 h after LPS or phosphate buffered saline (PBS) intratracheal instillation. Samples were harvested 24 h post LPS or PBS administration. Results AUDA administration decreased the pulmonary levels of monocyte chemoattractant protein (MCP)-1 and tumor necrosis factor (TNF)-α. Improvement of oxygenation and lung edema were observed in AUDA treated group. AUDA significantly inhibited sEH activity, and elevated epoxyeicosatrienoic acids (EETs) levels in lung tissues. Moreover, LPS induced the activation of nuclear factor (NF)-κB was markedly dampened in AUDA treated group. Conclusion Administration of AUDA after the onset of LPS-induced ALI increased pulmonary levels of EETs, and ameliorated lung injury. sEH is a potential pharmacologic target for ALI. PMID:27490848

  7. A Receptor Tyrosine Kinase Inhibitor, Dovitinib (TKI-258), Enhances BMP-2-Induced Osteoblast Differentiation In Vitro

    PubMed Central

    Lee, Yura; Bae, Kyoung Jun; Chon, Hae Jung; Kim, Seong Hwan; Kim, Soon Ae; Kim, Jiyeon

    2016-01-01

    Dovitinib (TKI258) is a small molecule multi-kinase inhibitor currently in clinical phase I/II/III development for the treatment of various types of cancers. This drug has a safe and effective pharmacokinetic/pharmacodynamic profile. Although dovitinib can bind several kinases at nanomolar concentrations, there are no reports relating to osteoporosis or osteoblast differentiation. Herein, we investigated the effect of dovitinib on human recombinant bone morphogenetic protein (BMP)-2-induced osteoblast differentiation in a cell culture model. Dovitinib enhanced the BMP-2-induced alkaline phosphatase (ALP) induction, which is a representative marker of osteoblast differentiation. Dovitinib also stimulated the translocation of phosphorylated Smad1/5/8 into the nucleus and phosphorylation of mitogen-activated protein kinases, including ERK1/2 and p38. In addition, the mRNA expression of BMP-4, BMP-7, ALP, and OCN increased with dovitinib treatment. Our results suggest that dovitinib has a potent stimulating effect on BMP-2-induced osteoblast differentiation and this existing drug has potential for repositioning in the treatment of bone-related disorders. PMID:27025387

  8. A Phase I, Dose-Finding Study of Sorafenib in Combination with Gemcitabine and Radiation Therapy in Patients with Unresectable Pancreatic Adenocarcinoma: A Grupo Español Multidisciplinario en Cáncer Digestivo (GEMCAD) Study

    PubMed Central

    Aparicio, Jorge; García-Mora, Carmen; Martín, Marta; Petriz, Ma Lourdes; Feliu, Jaime; Sánchez-Santos, Ma Elena; Ayuso, Juan Ramón; Fuster, David; Conill, Carlos; Maurel, Joan

    2014-01-01

    Purpose Sorafenib, an oral inhibitor of B-raf, VEGFR2, and PDGFR2-beta, acts against pancreatic cancer in preclinical models. Due to the radio-sensitization activity of both sorafenib and gemcitabine, we designed a multicenter, phase I trial to evaluate the safety profile and the recommended dose of this combination used with concomitant radiation therapy. Methods Patients with biopsy-proven, unresectable pancreatic adenocarcinoma (based on vascular invasion detected by computed tomography) were treated with gemcitabine (300 mg/m2 i.v. weekly ×5 weeks) concurrently with radiation therapy (45 Gy in 25 fractions) and sorafenib (escalated doses in a 3+3 design, from 200 to 800 mg/day). Radiation portals included the primary tumor but not the regional lymph nodes. Patients with planning target volumes (PTV) over 500 cc were excluded. Cases not progressing during chemoradiation were allowed to continue with sorafenib until disease progression. Results Twelve patients were included. Three patients received 200 mg/day, 6 received 400 mg/day, and 3 received 800 mg/day; PTVs ranged from 105 to 500 cc. No dose-limiting toxicities occurred. The most common grade 2 toxicities were fatigue, neutropenia, nausea, and raised serum transaminases. Treatment was discontinued in one patient because of a reversible posterior leukoencephalopathy. There were no treatment-related deaths. Conclusion The addition of sorafenib to concurrent gemcitabine and radiation therapy showed a favorable safety profile in unresectable pancreatic adenocarcinoma. A dose of 800 mg/day is recommended for phase II evaluation. Trial Registration EudraCT 2007-003211-31 ClinicalTrials.gov 00789763 PMID:24416138

  9. Mitigation and Treatment of Radiation-Induced Thoracic Injury With a Cyclooxygenase-2 Inhibitor, Celecoxib

    SciTech Connect

    Hunter, Nancy R.; Valdecanas, David; Liao Zhongxing; Milas, Luka; Thames, Howard D.; Mason, Kathy A.

    2013-02-01

    Purpose: To test whether a cyclooxygenase-2 inhibitor (celecoxib) could reduce mortality resulting from radiation-induced pneumonitis. Methods and Materials: Celecoxib was given to mice twice daily for 40 consecutive days starting on the day of local thoracic irradiation (LTI) or 40 or 80 days later. C3Hf/KamLaw mice were observed for morbidity, and time to death was determined. Results were analyzed using the Cox proportional hazards model. Results: Timing of celecoxib relative to LTI determined efficacy. A significant reduction in time to death was achieved only when celecoxib was started 80 days after LTI, corresponding to the time when pneumonitis is expressed. For these mice the reduction in mortality was quantified as a hazard ratio for mortality of treated vs untreated of 0.36 (95% confidence interval [CI] 0.24-0.53), thus significantly less than 1.0. Correspondingly, the median lethal dose for treated mice (12.9 Gy; 95% CI 12.55-13.25 Gy) was significantly (P=.026) higher than for untreated mice (12.4 Gy; 95% CI 12.2-12.65 Gy). Conclusions: Celecoxib significantly reduced lung toxicity when administered months after LTI when the deleterious effects of radiation were expressed. The schedule-dependent reduction in fatal pneumonitis suggests that celecoxib could be clinically useful by reintroduction of treatment months after completion of radiation therapy. These findings may be important for designing clinical trials using cyclooxygenase-2 inhibitors to treat radiation-induced lung toxicity as a complement to concurrent radiation therapy of lung cancers.

  10. Renoprotective effect of the xanthine oxidoreductase inhibitor topiroxostat on adenine-induced renal injury.

    PubMed

    Kamijo-Ikemori, Atsuko; Sugaya, Takeshi; Hibi, Chihiro; Nakamura, Takashi; Murase, Takayo; Oikawa, Tsuyoshi; Hoshino, Seiko; Hisamichi, Mikako; Hirata, Kazuaki; Kimura, Kenjiro; Shibagaki, Yugo

    2016-06-01

    The aim of the present study was to reveal the effect of a xanthine oxidoreductase (XOR) inhibitor, topiroxostat (Top), compared with another inhibitor, febuxostat (Feb), in an adenine-induced renal injury model. We used human liver-type fatty acid-binding protein (L-FABP) chromosomal transgenic mice, and urinary L-FABP, a biomarker of tubulointerstitial damage, was used to evaluate tubulointerstitial damage. Male transgenic mice (n = 24) were fed a 0.2% (wt/wt) adenine-containing diet. Two weeks after the start of this diet, renal dysfunction was confirmed, and the mice were divided into the following four groups: the adenine group was given only the diet containing adenine, and the Feb, high-dose Top (Top-H), and low-dose Top (Top-L) groups were given diets containing Feb (3 mg/kg), Top-H (3 mg/kg), and Top-L (1 mg/kg) in addition to adenine for another 2 wk. After withdrawal of the adenine diet, each medication was continued for 2 wk. Serum creatinine levels, the degree of macrophage infiltration, tubulointerstitial damage, renal fibrosis, urinary 15-F2t-isoprostane levels, and renal XOR activity were significantly attenuated in the kidneys of the Feb, Top-L, and Top-H groups compared with the adenine group. Serum creatinine levels in the Top-L and Top-H groups as well as renal XOR in the Top-H group were significantly lower than those in the Feb group. Urinary excretion of L-FABP in both the Top-H and Top-L groups was significantly lower than in the adenine and Feb groups. In conclusion, Top attenuated renal damage in an adenine-induced renal injury model. PMID:27029427

  11. Angiotensin-converting enzyme inhibitor (enalapril maleate) accelerates recovery of mouse skin from UVB-induced wrinkles

    SciTech Connect

    Matsuura-Hachiya, Yuko; Arai, Koji Y.; Ozeki, Rieko; Kikuta, Ayako; Nishiyama, Toshio

    2013-12-06

    Highlights: •Angiotensin converting enzyme (ACE) increases in UVB-irradiated skin. •Administration of an ACE inhibitor improved UVB-induced skin wrinkle. •ACE inhibitor improved UVB-induced epidermal hypertrophy. •ACE inhibitor improved transepidermal water loss in the UVB-irradiated skin. -- Abstract: Angiotensin-converting enzyme (ACE) activity and angiotensin II signaling regulate cell proliferation, differentiation, and tissue remodeling, as well as blood pressure, while in skin, angiotensin II signaling is involved in wound healing, inflammation, and pathological scar formation. Therefore, we hypothesized that angiotensin II is also involved in photoaging of skin. In this study, we examined the effect of enalapril maleate, an ACE inhibitor, on recovery of wrinkled skin of hairless mice exposed to long-term UVB irradiation. Immunohistochemical observation revealed that expression of ACE, angiotensin II, and angiotensin II type 1 (AT1) and type 2 (AT2) receptors in the skin was increased after UVB irradiation (3 times/week at increasing intensities for 8 weeks). Administration of enalapril maleate (5 times/week for 6 weeks, starting 1 week after 10-week irradiation) accelerated recovery from UVB-induced wrinkles, epidermal hyperplasia and epidermal barrier dysfunction, as compared with the vehicle control. Our results indicate that ACE and angiotensin II activity are involved in skin photoaging, and suggest that ACE inhibitor such as enalapril maleate may have potential for improvement of photoaged skin.

  12. The kinesin Eg5 inhibitor K858 induces apoptosis but also survivin-related chemoresistance in breast cancer cells.

    PubMed

    De Iuliis, Francesca; Taglieri, Ludovica; Salerno, Gerardo; Giuffrida, Anna; Milana, Bernardina; Giantulli, Sabrina; Carradori, Simone; Silvestri, Ida; Scarpa, Susanna

    2016-08-01

    Inhibitors of kinesin spindle protein Eg5 are characterized by pronounced antitumor activity. Our group has recently synthesized and screened a library of 1,3,4-thiadiazoline analogues with the pharmacophoric structure of K858, an Eg5 inhibitor. We herein report the effects of K858 on four different breast cancer cell lines: MCF7 (luminal A), BT474 (luminal B), SKBR3 (HER2 like) and MDA-MB231 (basal like). We demonstrated that K858 displayed anti-proliferative activity on every analyzed breast cancer cell line by inducing apoptosis. However, at the same time, we showed that K858 up-regulated survivin, an anti-apoptotic molecule. We then performed a negative regulation of survivin expression, with the utilization of wortmannin, an AKT inhibitor, and obtained a significant increase of K858-dependent apoptosis. These data demonstrate that K858 is a potent inhibitor of replication and induces apoptosis in breast tumor cells, independently from the tumor phenotype. This anti-proliferative response of tumor cells to K858 can be limited by the contemporaneous over-expression of survivin; consequently, the reduction of survivin levels, obtained with AKT inhibitors, can sensitize tumor cells to K858-induced apoptosis. PMID:26994617

  13. In vitro effects of cysteine protease inhibitors on Trichomonas foetus-induced cytopathic changes in porcine intestinal epithelial cells.

    PubMed

    Tolbert, M Katherine; Brand, Mabre D; Gould, Emily N

    2016-08-01

    OBJECTIVE To investigate the effects of specific cysteine protease (CP) inhibitors on cytopathic changes to porcine intestinal epithelial cells induced by Tritrichomonas foetus isolated from naturally infected cats. SAMPLE T foetus isolates from 4 naturally infected cats and nontransformed porcine intestinal epithelial cells. PROCEDURES T foetus isolates were treated with or without 0.1 to 1.0mM of the CP inhibitors antipain, cystatin, leupeptin, and chymostatin and the vinyl sulfone inhibitors WRR-483 and K11777. In-gel gelatin zymography was performed to evaluate the effects of these inhibitors on CP activity of T foetus isolates. Each treated or untreated isolate was also cocultured with monolayers of porcine intestinal epithelial cells for 24 hours, and cytopathic effects of T foetus were evaluated by light microscopy and crystal violet spectrophotometry. RESULTS Results of in-gel gelatin zymography suggested an ability of WRR-483, K11777, and cystatin to target specific zones of CP activity of the T foetus isolates. These inhibitors had no effect on T foetus growth, and the cytopathic changes to the intestinal epithelium induced by all 4 T foetus isolates were significantly inhibited. CONCLUSIONS AND CLINICAL RELEVANCE This study revealed that certain protease inhibitors were capable of inhibiting regions of CP activity (which has been suggested to cause intestinal cell damage in cats) in T foetus organisms and of ameliorating T foetus-induced cytopathic changes to porcine intestinal epithelium in vitro. Although additional research is needed, these inhibitors might be useful in the treatment of cats with trichomonosis. PMID:27463553

  14. Silencing of the polyamine catabolic key enzyme SSAT prevents CDK inhibitor-induced apoptosis in Caco-2 colon cancer cells.

    PubMed

    Çoker, A; Arısan, E D; Palavan-Ünsal, N

    2012-04-01

    Roscovitine and purvalanol are purine derivative cyclin-dependent kinase (CDK) inhibitors that induce apoptosis in various types of cancer cells. However, their impact on the apoptotic cell death mechanism requires further elucidation. Natural polyamines putrescine, spermidine and spermine play essential roles in the regulation of cell growth and proliferation. Increased levels of polyamines in cells are considered to be involved in cancer progression. Intracellular polyamine levels are under the control of several catabolic enzymes, such as spermidine/spermine-N-acetyl transferase (SSAT), acetylpolyamine oxidase (APAO) and spermine oxidase (SMO), which could be altered by several therapeutic drugs. However, the possible role of polyamines in drug-induced apoptosis has yet to be clarified. In the present study, our aim was to determine the modulation of the polyamine catabolic pathway related to CDK inhibitor-induced apoptosis in Caco-2 cells. We found that roscovitine and purvalanol (each 20 µM) induced apoptosis by activating caspase-9 and -3, and inhibiting the mitochondrial membrane potential in Caco-2 cells. CDK inhibitors decreased the intracellular putrescine and spermine levels without affecting spermidine levels. Although both roscovitine and purvalanol induced SSAT expression, they did not exert a significant effect on the APAO expression profile. SSAT transient silencing prevented roscovitine-induced apoptosis compared to parental cells. Thus, we concluded that roscovitine and purvalanol significantly induce apoptosis in Caco-2 cells by modulating the polyamine catabolism, and that SSAT could be an important target in evaluating the potential role of polyamines in apoptotic cell death. PMID:22294330

  15. The novel HDAC inhibitor AR-42-induced anti-colon cancer cell activity is associated with ceramide production

    SciTech Connect

    Xu, Weihong; Xu, Bin; Yao, Yiting; Yu, Xiaoling; Shen, Jie

    2015-08-07

    In the current study, we investigated the potential activity of AR-42, a novel histone deacetylase (HDAC) inhibitor, against colon cancer cells. Our in vitro results showed that AR-42 induced ceramide production, exerted potent anti-proliferative and pro-apoptotic activities in established (SW-620 and HCT-116 lines) and primary human colon cancer cells. Exogenously-added sphingosine 1-phosphate (S1P) suppressed AR-42-induced activity, yet a cell-permeable ceramide (C4) facilitated AR-42-induced cytotoxicity against colon cancer cells. In addition, AR-42-induced ceramide production and anti-colon cancer cell activity were inhibited by the ceramide synthase inhibitor fumonisin B1, but were exacerbated by PDMP, which is a ceramide glucosylation inhibitor. In vivo, oral administration of a single dose of AR-42 dramatically inhibited SW-620 xenograft growth in severe combined immunodeficient (SCID) mice, without inducing overt toxicities. Together, these results show that AR-42 dramatically inhibits colon cancer cell proliferation in vitro and in vivo, and ceramide production might be the key mechanism responsible for its actions. - Highlights: • AR-42 is anti-proliferative against primary/established colon cancer cells. • AR-42 induces significant apoptotic death in primary/established colon cancer cells. • Ceramide production mediates AR-42-induced cytotoxicity in colon cancer cells. • AR-42 oral administration potently inhibits SW-620 xenograft growth in SCID mice.

  16. A small molecule inhibitor of ubiquitin-specific protease-7 induces apoptosis in multiple myeloma cells and overcomes bortezomib resistance.

    PubMed

    Chauhan, Dharminder; Tian, Ze; Nicholson, Benjamin; Kumar, K G Suresh; Zhou, Bin; Carrasco, Ruben; McDermott, Jeffrey L; Leach, Craig A; Fulcinniti, Mariaterresa; Kodrasov, Matthew P; Weinstock, Joseph; Kingsbury, William D; Hideshima, Teru; Shah, Parantu K; Minvielle, Stephane; Altun, Mikael; Kessler, Benedikt M; Orlowski, Robert; Richardson, Paul; Munshi, Nikhil; Anderson, Kenneth C

    2012-09-11

    Bortezomib therapy has proven successful for the treatment of relapsed/refractory, relapsed, and newly diagnosed multiple myeloma (MM); however, dose-limiting toxicities and the development of resistance limit its long-term utility. Here, we show that P5091 is an inhibitor of deubiquitylating enzyme USP7, which induces apoptosis in MM cells resistant to conventional and bortezomib therapies. Biochemical and genetic studies show that blockade of HDM2 and p21 abrogates P5091-induced cytotoxicity. In animal tumor model studies, P5091 is well tolerated, inhibits tumor growth, and prolongs survival. Combining P5091 with lenalidomide, HDAC inhibitor SAHA, or dexamethasone triggers synergistic anti-MM activity. Our preclinical study therefore supports clinical evaluation of USP7 inhibitor, alone or in combination, as a potential MM therapy. PMID:22975377

  17. Sorafenib and a novel immune therapy in lung metastasis from hepatocellular carcinoma following hepatectomy: A case report

    PubMed Central

    Yi, Yongxiang; Han, Jianbo; Fang, Yuan; Liu, Dongxiao; Wu, Zuoyou; Wang, Lili; Zhao, Liang; Wei, Qiang

    2016-01-01

    Sorafenib is the standard therapeutic strategy for recurrent hepatocellular carcinoma (HCC) following hepatectomy. However, only few patients truly benefit from this therapy. Thus, new strategies combined with sorafenib are urgently required. We herein present the case of a patient with hepatic and extrahepatic HCC recurrence following hepatectomy, who was treated by combined sorafenib, focused ultrasound knife and DRibbles-pulsed dendritic cell (DC) vaccine. Enzyme-Linked ImmunoSpot assay (ELISPOT) and intracellular staining (ICS) analysis were used to detect the secretion of interferon (IFN)-γ by T cells at different timepoints of the vaccine in order to evaluate the patient's specific T-cell response to SMMC-7721-derived DRibbles vaccine. The α-fetoprotein level decreased from 103,295 to 5 ng/ml and the patient displayed improved liver function, an Eastern Cooperative Oncology Group performance status score of 0, remission of liver metastases and disappearance of the lung metastases 8 months post-combination therapy. The computed tomography scan revealed the disappearance of liver metastases 2 years post-combination therapy. The ELISPOT data revealed a low antigen-specific T-cell response 4 weeks after the first vaccine cycle and the response decreased to nearly zero prior to the second cycle. However, high antigen-specific T-cell response was observed 2 weeks after the second vaccine cycle and did not decrease, even after 10 months, which was consistent with the result of the ICS analysis, which demonstrated that most of the secreted IFN-γ was produced by CD4+ T cells, whereas a low CD8+ T-cell response was observed (0.429 vs. 0.0665%, respectively). Our results demonstrated that antigen-specific T-cell response aimed to treat recurrent HCC may be induced through stimulation by the DC-DRibbles vaccine. The success of the treatment supports the combination of sorafenib, focused ultrasound knife and DC-DRibbles vaccine as a therapeutic strategy for patients

  18. Mice lacking the Raf-1 kinase inhibitor protein exhibit exaggerated hypoxia-induced pulmonary hypertension

    PubMed Central

    Morecroft, I; Doyle, B; Nilsen, M; Kolch, W; Mair, K; MacLean, MR

    2011-01-01

    BACKGROUND AND PURPOSE Increased pulmonary vascular remodelling, pulmonary arterial pressure and pulmonary vascular resistance characterize the development of pulmonary arterial hypertension (PAH). Activation of the Raf/mitogen-activated protein kinase/extracellular signal-regulated kinase (ERK)1/2 is thought to play an important role in PAH and Raf-1 kinase inhibitor protein (RKIP), negatively regulates this pathway. This study investigated whether genetic deletion of RKIP (and hence ERK1/2 up-regulation) resulted in a pulmonary hypertensive phenotype in mice and investigated a role for RKIP in mitogen-regulated proliferative responses in lung fibroblasts. EXPERIMENTAL APPROACH Pulmonary vascular haemodynamics and remodelling were assessed in mice genetically deficient in RKIP (RKIP−/−) after 2 weeks of either normoxia or hypoxia. Immunoblotting and immunohistochemistry were used to examine phosphorylation of Raf-1, RKIP and ERK1/2 in mouse pulmonary arteries. In vitro, RKIP inhibition of mitogen signalling was analysed in CCL39 hamster lung fibroblasts. KEY RESULTS RKIP−/− mice demonstrated elevated indices of PAH and ERK1/2 phosphorylation compared with wild-type (WT) mice. Hypoxic RKIP−/− mice exhibited exaggerated PAH indices. Hypoxia increased phosphorylation of Raf-1, RKIP and ERK1/2 in WT mouse pulmonary arteries and Raf-1 phosphorylation in RKIP−/− mouse pulmonary arteries. In CCL39 cells, inhibition of RKIP potentiated mitogen-induced proliferation and phosphorylation of RKIP, and Raf-1. CONCLUSIONS AND IMPLICATIONS The lack of RKIP protein resulted in a pulmonary hypertensive phenotype, exaggerated in hypoxia. Hypoxia induced phosphorylation of RKIP signalling elements in WT pulmonary arteries. RKIP inhibition potentiated mitogen-induced proliferation in lung fibroblasts. These results provide evidence for the involvement of RKIP in suppressing the development of hypoxia-induced PAH in mice. PMID:21385176

  19. A novel NF-κB inhibitor, DHMEQ, ameliorates pristane-induced lupus in mice.

    PubMed

    Qu, Huiqing; Bian, Weihua; Xu, Yanyan

    2014-07-01

    Nuclear factor (NF)-κB is strongly associated with the development of immune regulation and inflammation. The aim of the present study was to identify whether a NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), ameliorates systemic lupus erythematosus (SLE) in a pristane-induced mouse model. SLE was induced in 8-week-old female BALB/c mice by the injection of 0.5 ml pristane. The therapeutic effect of 12 mg/kg DHMEQ on the pristane-induced BALB/c mouse model of lupus was investigated to elucidate the effects on SLE. The intraperitoneal administration of DHMEQ three times per week was initiated when the mice were 16 weeks-old (8 weeks following the pristane injection) and the treatment was continued for 16 weeks. Serum IgG autoantibodies against nucleosomes, dsDNA and histones were detected at weeks 8, 16 and 32. In addition, the expression levels of interleukin (IL)-1β, 6 and 17, as well as tumor necrosis factor (TNF)-α, were analyzed at week 32. Renal lesions were also observed. DHMEQ was shown to antagonize the increasing levels of anti-nucleosome, anti-dsDNA and anti-histone autoantibodies, as well as the increasing levels of IL-1β, 6 and 17 and TNF-α. In addition, DHMEQ reduced the number of renal lesions caused by pristane, as reflected by milder proteinuria and reduced renal pathology. The renal expression levels of phosphorylated-p38 mitogen-activated protein kinase (MAPK), phosphorylated-c-Jun N-terminal kinase (JNK) and NF-κB p65 were significantly downregulated. Therefore, the results of the present study indicate that DHMEQ has a beneficial effect on pristane-induced lupus through regulating cytokine levels and the MAPK/JNK/NF-κB signaling pathway. PMID:24944605

  20. A novel NF-κB inhibitor, DHMEQ, ameliorates pristane-induced lupus in mice

    PubMed Central

    QU, HUIQING; BIAN, WEIHUA; XU, YANYAN

    2014-01-01

    Nuclear factor (NF)-κB is strongly associated with the development of immune regulation and inflammation. The aim of the present study was to identify whether a NF-κB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), ameliorates systemic lupus erythematosus (SLE) in a pristane-induced mouse model. SLE was induced in 8-week-old female BALB/c mice by the injection of 0.5 ml pristane. The therapeutic effect of 12 mg/kg DHMEQ on the pristane-induced BALB/c mouse model of lupus was investigated to elucidate the effects on SLE. The intraperitoneal administration of DHMEQ three times per week was initiated when the mice were 16 weeks-old (8 weeks following the pristane injection) and the treatment was continued for 16 weeks. Serum IgG autoantibodies against nucleosomes, dsDNA and histones were detected at weeks 8, 16 and 32. In addition, the expression levels of interleukin (IL)-1β, 6 and 17, as well as tumor necrosis factor (TNF)-α, were analyzed at week 32. Renal lesions were also observed. DHMEQ was shown to antagonize the increasing levels of anti-nucleosome, anti-dsDNA and anti-histone autoantibodies, as well as the increasing levels of IL-1β, 6 and 17 and TNF-α. In addition, DHMEQ reduced the number of renal lesions caused by pristane, as reflected by milder proteinuria and reduced renal pathology. The renal expression levels of phosphorylated-p38 mitogen-activated protein kinase (MAPK), phosphorylated-c-Jun N-terminal kinase (JNK) and NF-κB p65 were significantly downregulated. Therefore, the results of the present study indicate that DHMEQ has a beneficial effect on pristane-induced lupus through regulating cytokine levels and the MAPK/JNK/NF-κB signaling pathway. PMID:24944605

  1. Molecular characterization and phylogenetic studies of a wound-inducible proteinase inhibitor I gene in Lycopersicon species.

    PubMed

    Lee, J S; Brown, W E; Graham, J S; Pearce, G; Fox, E A; Dreher, T W; Ahern, K G; Pearson, G D; Ryan, C A

    1986-10-01

    A gene coding for proteinase inhibitor I, whose expression is induced in tomato leaves (Lycopersicon esculentum L. var. Bonny Best) in response to wounding or insect attacks, was isolated from a genomic library and characterized. The nucleotide sequence revealed that the gene is complete and encodes the sequence of an inhibitor I cDNA that was previously isolated from a cDNA library prepared from wound-induced mRNA from tomato leaves. This gene is located 13.1 kilobase pairs (kbp) upstream from an inhibitor II gene. The wound-inducible gene is interrupted by two intervening sequences of 445 and 404 bp, situated within the codons of amino acids 17 and 47, respectively, of the open reading frame. In addition to the presence of putative regulatory sequences, TATAAA and CCACT, two copies of an imperfect direct repeat approximately 100 bp long were identified in the 5'-flanking region. Phylogenetic comparisons of wound-inducible inhibitor I genes within the genomes of various Lycopersicon species revealed that the repeat is found in seven ancestral species of tomato. PMID:3463966

  2. Effect of NADPH-oxidase inhibitors in the experimental model of zymosan-induced shock in mice.

    PubMed

    Impellizzeri, Daniela; Mazzon, Emanuela; Di Paola, Rosanna; Paterniti, Irene; Bramanti, Placido; Cuzzocrea, Salvatore

    2011-07-01

    The aim of this study was to investigate the effects of NADPH-oxidase inhibitors, in a mouse model of zymosan. Zymosan-induced shock was induced in mice by administration of zymosan (500 mg/kg, i.p.). The pharmacological treatment was the administration of apocynin (5 mg/kg 10% DMSO i.p.) and diphenylene iodonium chloride (DPI) (1 mg/kg i.v.) 1 h and 6 h after zymosan administration. MOF and systemic inflammation in mice was assessed 18 h after administration of zymosan. NADPH-oxidase inhibitors caused a significant reduction of the (1) peritoneal exudate formation, (2) neutrophil infiltration, (3) multiple organ dysfunction syndrome, (4) nitrotyrosine, (5) poly (ADP-ribose) (PAR), (6) cytokine formation, (7) adhesion molecule expression, (8) nuclear factor (NF-κB) expression and (9) apoptosis induced by zymosan. Moreover, NADPH-oxidase inhibitors treatment significantly reduced the systemic toxicity, the loss in body weight and the mortality caused by zymosan. This study has shown that NADPH-oxidase inhibitors attenuate the degree of zymosan-induced non-septic shock in mice. PMID:21623687

  3. Resistance of Renal Cell Carcinoma to Sorafenib Is Mediated by Potentially Reversible Gene Expression

    PubMed Central

    Schor-Bardach, Rachel; Wang, Xiaoen; Collins, Michael P.; Panka, David; Putheti, Prabhakar; Signoretti, Sabina; Alsop, David C.; Libermann, Towia; Atkins, Michael B.; Mier, James W.; Goldberg, S. Nahum; Bhatt, Rupal S.

    2011-01-01

    Purpose Resistance to antiangiogenic therapy is an important clinical problem. We examined whether resistance occurs at least in part via reversible, physiologic changes in the tumor, or results solely from stable genetic changes in resistant tumor cells. Experimental Design Mice bearing two human RCC xenografts were treated with sorafenib until they acquired resistance. Resistant 786-O cells were harvested and reimplanted into naïve mice. Mice bearing resistant A498 cells were subjected to a 1 week treatment break. Sorafenib was then again administered to both sets of mice. Tumor growth patterns, gene expression, viability, blood vessel density, and perfusion were serially assessed in treated vs control mice. Results Despite prior resistance, reimplanted 786-O tumors maintained their ability to stabilize on sorafenib in sequential reimplantation steps. A transcriptome profile of the tumors revealed that the gene expression profile of tumors upon reimplantation reapproximated that of the untreated tumors and was distinct from tumors exhibiting resistance to sorafenib. In A498 tumors, revascularization was noted with resistance and cessation of sorafenib therapy and tumor perfusion was reduced and tumor cell necrosis enhanced with re-exposure to sorafenib. Conclusions In two RCC cell lines, resistance to sorafenib appears to be reversible. These results support the hypothesis that resistance to VEGF pathway therapy is not solely the result of a permanent genetic change in the tumor or selection of resistant clones, but rather is due to a great extent to reversible changes that likely occur in the tumor and/or its microenvironment. PMID:21559452

  4. Sorafenib treatment during partial hepatectomy reduces tumorgenesis in an inflammation-associated liver cancer model.

    PubMed

    Zahavi, Tamar; Lanton, Tali; Divon, Mali Salmon; Salmon, Asher; Peretz, Tamar; Galun, Eithan; Axelrod, Jonathan H; Sonnenblick, Amir

    2016-01-26

    The long-term prognosis after resection of hepatocellular carcinoma (HCC), which is one of the treatment options for early-stage HCC, remains unsatisfactory as a result of a high incidence of disease recurrence. Recent studies performed in murine models revealed a link between liver regeneration under chronic inflammation and hepatic tumorigenesis. Sorafenib is a potent drug for advanced HCC with multikinase inhibition activity. We propose that inhibition of signal transduction pathways which are activated during hepatectomy, using Sorafenib, will reduce accelerated tumorigenesis. To test this hypothesis, we studied the Mdr2-knockout (KO) mouse strain, a model of inflammation-associated cancer, which underwent partial hepatectomy (PHx) at three months of age, with or without Sorafenib.Here we show that Sorafenib treatment during PHx inhibited different signal transduction pathways at the multikinase levels, but did not result in increased morbidity or mortality. At the early stages after PHx, Sorafenib treatment had no effect on the course of proliferation, apoptosis and DNA repair in the regenerating liver, but resulted in decreased stellate cells activation and inflammatory response. Finally, we show that Sorafenib treatment during PHx at three months of age resulted in decreased fibrosis and tumor formation at 8.5 months.In conclusion our study indicates that short-term Sorafenib treatment during PHx is safe and effective in inhibiting inflammation-associated cancer, and is therefore a potential strategy for recurrence prevention in patients with early-stage HCC treated with PHx. PMID:26695439

  5. Sorafenib treatment during partial hepatectomy reduces tumorgenesis in an inflammation-associated liver cancer model

    PubMed Central

    Salmon, Asher; Peretz, Tamar; Galun, Eithan; Axelrod, Jonathan H.; Sonnenblick, Amir

    2016-01-01

    The long-term prognosis after resection of hepatocellular carcinoma (HCC), which is one of the treatment options for early-stage HCC, remains unsatisfactory as a result of a high incidence of disease recurrence. Recent studies performed in murine models revealed a link between liver regeneration under chronic inflammation and hepatic tumorigenesis. Sorafenib is a potent drug for advanced HCC with multikinase inhibition activity. We propose that inhibition of signal transduction pathways which are activated during hepatectomy, using Sorafenib, will reduce accelerated tumorigenesis. To test this hypothesis, we studied the Mdr2-knockout (KO) mouse strain, a model of inflammation-associated cancer, which underwent partial hepatectomy (PHx) at three months of age, with or without Sorafenib. Here we show that Sorafenib treatment during PHx inhibited different signal transduction pathways at the multikinase levels, but did not result in increased morbidity or mortality. At the early stages after PHx, Sorafenib treatment had no effect on the course of proliferation, apoptosis and DNA repair in the regenerating liver, but resulted in decreased stellate cells activation and inflammatory response. Finally, we show that Sorafenib treatment during PHx at three months of age resulted in decreased fibrosis and tumor formation at 8.5 months. In conclusion our study indicates that short-term Sorafenib treatment during PHx is safe and effective in inhibiting inflammation-associated cancer, and is therefore a potential strategy for recurrence prevention in patients with early-stage HCC treated with PHx. PMID:26695439

  6. [Plasma Biomarkers as Predictive Factors for Advanced Hepatocellular Carcinoma with Sorafenib].

    PubMed

    Shiozawa, Kazue; Watanabe, Manabu; Ikehara, Takashi; Matsukiyo, Yasushi; Kogame, Michio; Shinohara, Mie; Kikuchi, Yoshinori; Igarashi, Yoshinori; Sumino, Yasukiyo

    2016-07-01

    We examined plasma biomarkers as predictive factors for advanced hepatocellular carcinoma(ad-HCC)patients treated with sorafenib. We analyzed a-fetoprotein(AFP), AFP-L3, des-g-carboxy prothrombin(DCP), neutrophil-to-lymphocyte ratio(NLR), platelet-to-lymphocyte ratio(PLR), and vascular endothelial growth factor(VEGF)before sorafenib therapy, and changes in AFP-L3, NLR, PLR, and VEGF 1 month after sorafenib therapy in 16 patients. High AFP-L3(hazard ratio: 1.058, 95%CI: 1.019-1.098, p=0.003)and high NLR(hazard ratio: 1.475, 95%CI: 1.045-2.082, p=0.027)were significantly associated with poor prognosis in ad-HCC patients treated with sorafenib. There were no significant differences in changes in AFP-L3, NLR, PLR, and VEGF 1 month after sorafenib therapy. We suggest that AFP-L3 and NLR levels before sorafenib therapy in patients with ad-HCC are an important predictive factor for the therapeutic effect of sorafenib and patient survival. PMID:27431630

  7. Last line therapy with sorafenib in colorectal cancer: A retrospective analysis

    PubMed Central

    Martchenko, Ksenia; Schmidtmann, Irene; Thomaidis, Thomas; Thole, Verena; Galle, Peter R; Becker, Marc; Möhler, Markus; Wehler, Thomas C; Schimanski, Carl C

    2016-01-01

    AIM: To analyze the efficacy of last line sorafenib treatment in colorectal cancer patients. METHODS: All patients receiving chemotherapy for colorectal cancer in the outpatient clinic of the University of Mainz since 2006 were retrospectively analyzed for last line sorafenib exposure. Charts of identified patients were analyzed for clinic-pathological parameters, like data on gender, age, date of initial diagnosis, UICC stage, number and kind of the pre-therapies, therapy start and end of sorafenib, sorafenib mediated treatment cessation, side effects, response rates, time to progression and overall survival. RESULTS: Ten patients with a median of 3.0 prior chemotherapy lines had received a last line sorafenib therapy either alone (10%) or in combination with 5-fluorouracil derivates (90%). All patients suffered from colorectal cancer stage UICC 4 and were routinely seen in 2-wk intervals in the oncology outpatient clinic. Median duration of treatment was 142.0 d. At 8 wk 80% of patients showed stable disease but we did not observe any remissions. Median time to progression was 140.5 d (4.7 mo), while median overall survival reached 176.5 d. One patient ceased treatment due to side effects. Reason for treatment stop was bleeding complication in one case and non-specified sorafenib intolerance in another case. Due to the retrospective approach we did not further quantify side effects. CONCLUSION: This retrospective analysis encourages further investigation of sorafenib in colorectal cancer last line therapy. PMID:27340356

  8. MET inhibitor PHA-665752 suppresses the hepatocyte growth factor-induced cell proliferation and radioresistance in nasopharyngeal carcinoma cells

    SciTech Connect

    Liu, Tongxin; Li, Qi; Sun, Quanquan; Zhang, Yuqin; Yang, Hua; Wang, Rong; Chen, Longhua; Wang, Wei

    2014-06-20

    Highlights: • We demonstrated that irradiation induced MET overexpression and activation. • The aberrant MET signal mediated by HGF induced proliferation and radioresistance of NPC cells. • MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. • PHA-665752 suppressed the three downstream pathway of HGF/MET signal in a dose-dependent manner. - Abstract: Although ionizing radiation (IR) has provided considerable improvements in nasopharyngeal carcinoma (NPC), in subsets of patients, radioresistance is still a major problem in the treatment. In this study, we demonstrated that irradiation induced MET overexpression and activation, and the aberrant MET signal mediated by hepatocyte growth factor (HGF) induced radioresistance. We also found that MET inhibitor PHA-665752 effectively suppressed HGF induced cell proliferation and radioresistance in NPC cells. Further investigation indicated that PHA-665752 suppressed the phosphorylation of the Akt, ERK1/2, and STAT3 proteins in a dose-dependent manner. Our data indicated that the combination of IR with a MET inhibitor, such as PHA-665752, might be a promising therapeutic strategy for NPC.

  9. A novel tissue model for angiogenesis: evaluation of inhibitors or promoters in tissue level

    NASA Astrophysics Data System (ADS)

    Dai, Bingling; Zhang, Yanmin; Zhan, Yingzhuan; Zhang, Dongdong; Wang, Nan; He, Langchong

    2014-01-01

    A novel tissue model for angiogenesis (TMA) is established for effective evaluation of angiogenesis inhibitors or promoters in vitro. Lung tissues were cultured in fibrinogen ``sandwich'' structure which resembled the formation of neovessels in vivo. The cells and capillary-like structures grew from the lung tissues were identified as endothelial cells and neovessels. Both immunohistochemisty and western blot results indicated that autocrine VEGF bound to the KDR and induced KDR autophosphorylation that could induce the proliferation of endothelial cells and their migration as well as the formation of microvessels on the lung tissue edge. With addition of the TMA, the murine VEGF and cultured medium produced by A549 tumor cells apparently promoted the increase of neovessels. Sorafenib as a tumor angiogenesis inhibitor and Tongxinluo as an angiogenesis promoter were both used to evaluate the TMA performance and they exhibited a good effect on neovessels in the TMA. The model established imitated angiogenesis in vivo and could well serve as an effective method in evaluating the angiogenesis inhibitors or promoters, and could also be practical for screening small molecules that affect blood vessel formation.

  10. Modified transarterial chemoembolization with locoregional administration of sorafenib for treating hepatocellular carcinoma: feasibility, efficacy, and safety in the VX-2 rabbit liver tumor model

    PubMed Central

    Seidensticker, Max; Streit, Sebastian; Nass, Norbert; Wybranski, Christian; Jürgens, Julian; Brauner, Jan; Schulz, Nadine; Kalinski, Thomas; Seidensticker, Ricarda; Garlipp, Benjamin; Steffen, Ingo; Ricke, Jens; Dudeck, Oliver

    2016-01-01

    PURPOSE We aimed to assess the feasibility, efficacy and safety of a local application of sorafenib within a conventional transarterial chemoembolization in the VX-2 tumor-bearing rabbit model. METHODS VX-2 tumors were induced in the left liver lobe of 10 New Zealand White rabbits. After two weeks, growth was verified by contrast-enhanced computed tomography (CT). Five rabbits were treated by transarterial chemoembolization using an emulsion of sorafenib and ethiodized oil (referred to as SORATACE; n=5). Rabbits receiving oral sorafenib for two weeks (n=2) and untreated rabbits (n=3) served as controls. After two weeks, contrast-enhanced CT was performed, followed by animal necropsy. RESULTS The change in tumor diameter between baseline and follow-up was significantly different in the SORATACE group compared with the other groups; tumor shrinkage was observed in the SORATACE group only (P = 0.016). In both control groups, preserved hypervascularity was seen in the follow-up CT in all but one tumor. All tumors in the SORATACE group were devascularized in the follow-up CT. Importantly, substantial parenchymal damage in nontargeted areas of the tumor-bearing liver lobe was seen in rabbits treated with SORATACE. CONCLUSION SORATACE demonstrated high efficacy in the treatment of experimental VX-2 liver tumors but was also associated with substantial liver parenchymal toxicity. PMID:27328720

  11. Genistein cooperates with the histone deacetylase inhibitor vorinostat to induce cell death in prostate cancer cells

    PubMed Central

    2012-01-01

    Background Among American men, prostate cancer is the most common, non-cutaneous malignancy that accounted for an estimated 241,000 new cases and 34,000 deaths in 2011. Previous studies have suggested that Wnt pathway inhibitory genes are silenced by CpG hypermethylation, and other studies have suggested that genistein can demethylate hypermethylated DNA. Genistein is a soy isoflavone with diverse effects on cellular proliferation, survival, and gene expression that suggest it could be a potential therapeutic agent for prostate cancer. We undertook the present study to investigate the effects of genistein on the epigenome of prostate cancer cells and to discover novel combination approaches of other compounds with genistein that might be of translational utility. Here, we have investigated the effects of genistein on several prostate cancer cell lines, including the ARCaP-E/ARCaP-M model of the epithelial to mesenchymal transition (EMT), to analyze effects on their epigenetic state. In addition, we investigated the effects of combined treatment of genistein with the histone deacetylase inhibitor vorinostat on survival in prostate cancer cells. Methods Using whole genome expression profiling and whole genome methylation profiling, we have determined the genome-wide differences in genetic and epigenetic responses to genistein in prostate cancer cells before and after undergoing the EMT. Also, cells were treated with genistein, vorinostat, and combination treatment, where cell death and cell proliferation was determined. Results Contrary to earlier reports, genistein did not have an effect on CpG methylation at 20 μM, but it did affect histone H3K9 acetylation and induced increased expression of histone acetyltransferase 1 (HAT1). In addition, genistein also had differential effects on survival and cooperated with the histone deacteylase inhibitor vorinostat to induce cell death and inhibit proliferation. Conclusion Our results suggest that there are a number of

  12. Adjuvant sorafenib therapy in patients with resected hepatocellular carcinoma: evaluation of predictive factors.

    PubMed

    Zhang, Wei; Zhao, Gang; Wei, Kai; Zhang, Qingxiang; Ma, Weiwei; Wu, Qiang; Zhang, Ti; Kong, Dalu; Li, Qiang; Song, Tianqiang

    2015-04-01

    Currently there is no predictor for survival after adjuvant sorafenib in patients with hepatocellular carcinoma (HCC) who have undergone curative resection. Thirty-eight patients who underwent curative resection of HCC received adjuvant sorafenib therapy between August 2009 and March 2012. Clinicopathological parameters including patient factors, tumor factors, liver background, and inflammatory factors (before surgery and dynamic changes after sorafenib therapy) were evaluated to identify predictors for overall survival (OS) and recurrence-free survival (RFS). The recurrence rate, mortality rate, and clinicopathological data were also compared. Increased NLR after sorafenib (HR = 3.199, 95 % CI 1.365-7.545, P = 0.008), increased GGT after sorafenib (HR = 3.204, 95 % CI 1.333-7.700, P = 0.009), and the presence of portal vein thrombosis (HR = 2.381, 95 % CI 1.064-5.328, P = 0.035) were risk factors related to RFS. By contrast, increased NLR after sorafenib was the only independent risk factor related to OS (HR = 4.647, 95 % CI 1.266-17.053, P = 0.021). Patients with increased NLR or increased GGT after sorafenib had a higher incidence of recurrence and death. Patients who had increased NLR tended to have higher preoperative levels of NLR and GGT. There were no differences in clinicopathological factors in patients with increased GGT and decreased GGT. In conclusion, increased NLR predicted a worse OS and RFS in patients with HCC who underwent curative resection with adjuvant sorafenib therapy. Increased GGT predicted a worse OS. NLR and GGT can be monitored dynamically before and after sorafenib therapy. PMID:25750040

  13. Beneficial effects of nilotinib, tyrosine kinase inhibitor on cyclosporine-A induced renal damage in rats.

    PubMed

    Nader, Manar A; Attia, Ghalia M

    2016-04-01

    Nilotinib is a known tyrosine kinase inhibitor that has been approved for treatment of leukemia. The possible protective effect of nilotinib on cyclosporine A-induced nephropathy was investigated in this study and the possible underlying mechanism was explored. Nilotinib (25mg/kg, orally) and cyclosporine A (15 mg/kg/day, subcutaneous) were given to male SD rats for 28 days. Cyclosporine A alone was found to significantly increase serum creatinine, blood urea nitrogen, lactate dehydrogenase, urinary micrototal protein, renal thiobarbituric acid reactive substance, Bax, cytosol cytochrome c release and nuclear factor kappa B activation. Moreover, cyclosporine A significantly reduced serum albumin, creatinine clearance, urinary total antioxidant, superoxide dismutase, glutathione and Bcl2 protein levels. Pathological results showed that in the model group; there was an obvious shrinkage and congestion of the glomeruli and widening of urinary spaces of renal corpuscles, in addition to marked renal tubular injury and fibrosis, while in the group pretreated with nilotinib all measured serum, renal and pathological changes were significantly reduced. This protective effect of nilotinib is linked to the enhanced antioxidant status and reduced inflammation and apoptosis induced by cyclosporine A. PMID:26844915

  14. A lysophosphatidic acid analogue is revealed as a potent inhibitor of phosphatidylcholine synthesis, inducing apoptosis.

    PubMed Central

    Gueguen, Geneviéve; Granci, Virginie; Rogalle, Pierre; Briand-Mésange, Fabienne; Wilson, Michéle; Klaébé, Alain; Tercé, François; Chap, Hugues; Salles, Jean-Pierre; Simon, Marie-Françoise; Gaits, Frédérique

    2002-01-01

    A previous study demonstrated that cross-desensitization experiments performed with the lysophosphatidic acid (LPA) analogues (R)- and (S)-N-palmitoyl-norleucinol 1-phosphate (PNPAs) inhibited LPA-induced platelet aggregation without any stereospecificity. Here we report opposite biological effects of the two enantiomers on mitogenesis of IMR-90 fibroblasts in relation to their respective metabolism. (R)PNPA was proliferative, while (S)PNPA induced apoptosis by specifically inhibiting phosphatidylcholine biosynthesis at the last step of the CDP-choline pathway controlled by cholinephosphotransferase. This effect was not direct but required dephosphorylation of PNPAs by ecto-lipid phosphate phosphatase before cellular uptake of the generated N-palmitoyl-norleucinols (PNOHs). Inhibition of cholinephosphotransferase by the derivative (S)PNOH was confirmed by an in vitro assay. (S)PNPA proapoptotic effects led us to clarify the mechanism linking cholinephosphotransferase inhibition to apoptosis. Three proapoptotic responses were observed: the activation of caspase-3, the production of ceramides from newly synthesized pools (as demonstrated by the inhibitor Fumonisin B1) and finally the activation of stress-activated protein kinase, p38 and c-Jun N-terminal kinases 1/2, as a result of ceramide increase. Thus our data demonstrate that synthetic analogues of LPA might display stereospecific effects leading to apoptosis independently of classical LPA-activated pathways. PMID:12197836

  15. An NLRP3-specific inflammasome inhibitor attenuates crystal-induced kidney fibrosis in mice.

    PubMed

    Ludwig-Portugall, Isis; Bartok, Eva; Dhana, Ermanila; Evers, Beatrix D G; Primiano, Michael J; Hall, J Perry; Franklin, Bernardo S; Knolle, Percy A; Hornung, Veit; Hartmann, Gunther; Boor, Peter; Latz, Eicke; Kurts, Christian

    2016-09-01

    Intrarenal crystal formation activates the Nlrp3 inflammasome in myeloid cells and triggers a profound inflammatory response. Here, we studied whether a specific inhibitor of the Nlrp3 inflammasome, CP-456,773, can prevent kidney fibrosis in a murine model of crystal nephropathy induced by diets rich in oxalate or adenine. Inflammasome activation in renal dendritic cells and the resulting interleukin (IL)-1β and IL-18 production were markedly reduced by CP-456,773 treatment both ex vivo and in vivo. We directly visualized intrarenal inflammasome activation and its inhibition by CP-456,773 in vivo by adoptive transfer of bone marrow cells transduced with interleukin-1β-Gaussia luciferase, a proteolytic luciferase-based reporter for inflammasome activation, into irradiated mice. CP-456,773 treatment strongly attenuated kidney fibrosis when given early in the genesis of crystal nephropathy, but was unable to reverse established crystal-induced fibrosis. The urinary IL-18 concentration appeared to be a useful noninvasive biomarker for renal inflammasome activation. Finally, NLRP3 inhibition did not compromise adaptive immune responses as previously reported for the global inhibition of IL-1 signaling. Thus, early NLRP3 inhibition by CP-456,773 may be an effective treatment for crystal nephropathy. Use of iGLuc transfected cells introduces a novel imaging technique for inflammasome activation in mice. PMID:27262364

  16. Small molecule inhibitors of Clostridium difficile toxin B-induced cellular damage.

    PubMed

    Tam, John; Beilhartz, Greg L; Auger, Anick; Gupta, Pulkit; Therien, Alex G; Melnyk, Roman A

    2015-02-19

    Clostridium difficile causes life-threatening diarrhea through the actions of its homologous toxins TcdA and TcdB on human colonocytes. Therapeutic agents that block toxin-induced damage are urgently needed to prevent the harmful consequences of toxin action that are not addressed with current antibiotic-based treatments. Here, we developed an imaging-based phenotypic screen to identify small molecules that protected human cells from TcdB-induced cell rounding. A series of structurally diverse compounds with antitoxin activity were identified and found to act through one of a small subset of mechanisms, including direct binding and sequestration of TcdB, inhibition of endosomal maturation, and noncompetitive inhibition of the toxin glucosyltransferase activity. Distinct classes of inhibitors were used further to dissect the determinants of the toxin-mediated necrosis phenotype occurring at higher doses of toxin. These findings validate and inform novel targeting strategies for discovering small molecule agents to treat C. difficile infection. PMID:25619932

  17. The NADPH oxidase inhibitor apocynin induces nitric oxide synthesis via oxidative stress

    SciTech Connect

    Riganti, Chiara

    2008-05-01

    We have recently shown that apocynin elicits an oxidative stress in N11 mouse glial cells and other cell types. Here we report that apocynin increased the accumulation of nitrite, the stable derivative of nitric oxide (NO), in the extracellular medium of N11 cell cultures, and the NO synthase (NOS) activity in cell lysates. The increased synthesis of NO was associated with increased expression of inducible NOS (iNOS) mRNA, increased nuclear translocation of the redox-sensitive transcription factor NF-{kappa}B and decreased intracellular level of its inhibitor IkB{alpha}. These effects, accompanied by increased production of H{sub 2}O{sub 2}, were very similar to those observed after incubation with bacterial lipopolysaccharide (LPS) and were inhibited by catalase. These results suggest that apocynin, similarly to LPS, induces increased NO synthesis by eliciting a generation of reactive oxygen species (ROS), which in turn causes NF-{kappa}B activation and increased expression of iNOS. Therefore, the increased bioavailability of NO reported in the literature after in vivo or in vitro treatments with apocynin might depend, at least partly, on the drug-elicited induction of iNOS, and not only on the inhibition of NADPH oxidase and the subsequent decreased scavenging of NO by oxidase-derived ROS, as it is often supposed.

  18. Panhistone deacetylase inhibitors inhibit proinflammatory signaling pathways to ameliorate interleukin-18-induced cardiac hypertrophy

    PubMed Central

    Majumdar, Gipsy; Rooney, Robert J.; Johnson, I. Maria

    2011-01-01

    We investigated the genome-wide consequences of pan-histone deacetylase inhibitors (HDACIs) trichostatin A (TSA) and m-carboxycinnamic acid bis-hydroxamide (CBHA) in the hearts of BALB/c mice eliciting hypertrophy in response to interleukin-18 (IL-18). Both TSA and CBHA profoundly altered cardiac chromatin structure that occurred concomitantly with normalization of IL-18-induced gene expression and amelioration of cardiac hypertrophy. The hearts of mice exposed to IL-18 +/− TSA or CBHA elicited distinct gene expression profiles. Of 184 genes that were differentially regulated by IL-18 and TSA, 33 were regulated in an opposite manner. The hearts of mice treated with IL-18 and/or CBHA elicited 147 differentially expressed genes (DEGs), a third of which were oppositely regulated by IL-18 and CBHA. Ingenuity Pathways and Kyoto Encyclopedia of Genes and Genomes analyses of DEGs showed that IL-18 impinged on TNF-α- and IFNγ-specific gene networks relegated to controlling immunity and inflammation, cardiac metabolism and energetics, and cell proliferation and apoptosis. These TNF-α- and IFNγ-specific gene networks, extensively connected with PI3K, MAPK, and NF-κB signaling pathways, were oppositely regulated by IL-18 and pan-HDACIs. Evidently, both TSA and CBHA caused a two- to fourfold induction of phosphatase and tensin homolog expression to counteract IL-18-induced proinflammatory signaling and cardiac hypertrophy. PMID:21954451

  19. Effect of a p38 MAPK inhibitor on FFA-induced hepatic insulin resistance in vivo

    PubMed Central

    Pereira, S; Yu, W Q; Moore, J; Mori, Y; Tsiani, E; Giacca, A

    2016-01-01

    The mechanisms whereby prolonged plasma free fatty acids elevation, as found in obesity, causes hepatic insulin resistance are not fully clarified. We herein investigated whether inhibition of p38 mitogen-activated protein kinase (MAPK) prevented hepatic insulin resistance following prolonged lipid infusion. Chronically cannulated rats were subdivided into one of four intravenous (i.v.) treatments that lasted 48 h: Saline (5.5 μl min−1), Intralipid plus heparin (IH, 20% Intralipid+20 U ml−1 heparin; 5.5 μl min−1), IH+p38 MAPK inhibitor (SB239063) and SB239063 alone. During the last 2 h of treatment, a hyperinsulinemic (5 mU kg−1 min−1) euglycemic clamp together with [3-3H] glucose methodology was carried out to distinguish hepatic from peripheral insulin sensitivity. We found that SB239063 prevented IH-induced hepatic insulin resistance, but not peripheral insulin resistance. SB239063 also prevented IH-induced phosphorylation of activating transcription factor 2 (ATF2), a marker of p38 MAPK activity, in the liver. Moreover, in another lipid infusion model in mice, SB239063 prevented hepatic but not peripheral insulin resistance caused by 48 h combined ethyloleate plus ethylpalmitate infusion. Our results suggest that inhibition of p38 MAPK may be a useful strategy in alleviating hepatic insulin resistance in obesity-associated disorders. PMID:27136448

  20. Effect of a p38 MAPK inhibitor on FFA-induced hepatic insulin resistance in vivo.

    PubMed

    Pereira, S; Yu, W Q; Moore, J; Mori, Y; Tsiani, E; Giacca, A

    2016-01-01

    The mechanisms whereby prolonged plasma free fatty acids elevation, as found in obesity, causes hepatic insulin resistance are not fully clarified. We herein investigated whether inhibition of p38 mitogen-activated protein kinase (MAPK) prevented hepatic insulin resistance following prolonged lipid infusion. Chronically cannulated rats were subdivided into one of four intravenous (i.v.) treatments that lasted 48 h: Saline (5.5 μl min(-1)), Intralipid plus heparin (IH, 20% Intralipid+20 U ml(-1) heparin; 5.5 μl min(-1)), IH+p38 MAPK inhibitor (SB239063) and SB239063 alone. During the last 2 h of treatment, a hyperinsulinemic (5 mU kg(-1) min(-1)) euglycemic clamp together with [3-(3)H] glucose methodology was carried out to distinguish hepatic from peripheral insulin sensitivity. We found that SB239063 prevented IH-induced hepatic insulin resistance, but not peripheral insulin resistance. SB239063 also prevented IH-induced phosphorylation of activating transcription factor 2 (ATF2), a marker of p38 MAPK activity, in the liver. Moreover, in another lipid infusion model in mice, SB239063 prevented hepatic but not peripheral insulin resistance caused by 48 h combined ethyloleate plus ethylpalmitate infusion. Our results suggest that inhibition of p38 MAPK may be a useful strategy in alleviating hepatic insulin resistance in obesity-associated disorders. PMID:27136448

  1. A Sphingolipid Inhibitor Induces a Cytokinesis Arrest and Blocks Stage Differentiation in Giardia lamblia▿

    PubMed Central

    Sonda, Sabrina; Štefanić, Saša; Hehl, Adrian B.

    2008-01-01

    Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 μM. The inhibition of parasite replication was irreversible at 10 μM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents. PMID:18086854

  2. A sphingolipid inhibitor induces a cytokinesis arrest and blocks stage differentiation in Giardia lamblia.

    PubMed

    Sonda, Sabrina; Stefanic, Sasa; Hehl, Adrian B

    2008-02-01

    Sphingolipid biosynthesis pathways have recently emerged as a promising target for therapeutic intervention against pathogens, including parasites. A key step in the synthesis of complex sphingolipids is the glucosylation of ceramide, mediated by glucosylceramide (GlcCer) synthase, whose activity can be inhibited by PPMP (1-phenyl-2-palmitoylamino-3-morpholino-1-propanol). In this study, we investigated whether PPMP inhibits the proliferation and differentiation of the pathogenic parasite Giardia lamblia, the major cause of parasite-induced diarrhea worldwide. PPMP was found to block in vitro parasite replication in a dose-dependent manner, with a 50% inhibitory concentration of 3.5 muM. The inhibition of parasite replication was irreversible at 10 muM PPMP, a concentration that did not affect mammalian cell metabolism. Importantly, PPMP inhibited the completion of cell division at a specific stage in late cytokinesis. Microscopic analysis of cells incubated with PPMP revealed the aberrant accumulation of cellular membranes belonging to the endoplasmic reticulum network in the caudal area of the parasites. Finally, PPMP induced a 90% reduction in G. lamblia differentiation into cysts, the parasite stage responsible for the transmission of the disease. These results show that PPMP is a powerful inhibitor of G. lamblia in vitro and that as-yet-uncharacterized sphingolipid biosynthetic pathways are potential targets for the development of anti-G. lamblia agents. PMID:18086854

  3. HDAC inhibitors induce global changes in histone lysine and arginine methylation and alter expression of lysine demethylases.

    PubMed

    Lillico, Ryan; Sobral, Marina Gomez; Stesco, Nicholas; Lakowski, Ted M

    2016-02-01

    Histone deacetylase (HDAC) inhibitors are cancer treatments that inhibit the removal of the epigenetic modification acetyllysine on histones, resulting in altered gene expression. Such changes in expression may influence other histone epigenetic modifications. We describe a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify lysine acetylation and methylation and arginine methylation on histones extracted from cultured cells treated with HDAC inhibitors. The HDAC inhibitors vorinostat, mocetinostat and entinostat induced 400-600% hyperacetylation in HEK 293 and K562 cells. All HDAC inhibitors decreased histone methylarginines in HEK 293 cells but entinostat produced dose dependent reductions in asymmetric dimethylarginine, not observed in K562 cells. Vorinostat produced increases in histone lysine methylation and decreased expression of some lysine demethylases (KDM), measured by quantitative PCR. Entinostat had variable effects on lysine methylation and decreased expression of some KDM while increasing expression of others. Mocetinostat produced dose dependent increases in histone lysine methylation by LC-MS/MS. This was corroborated with a multiplex colorimetric assay showing increases in histone H3 lysine 4, 9, 27, 36 and 79 methylation. Increases in lysine methylation were correlated with dose dependent decreases in the expression of seven KDM. Mocetinostat functions as an HDAC inhibitor and a de facto KDM inhibitor. PMID:26721445

  4. Nitric oxide synthase inhibitors can antagonize neurogenic and calcitonin gene-related peptide induced dilation of dural meningeal vessels

    PubMed Central

    Akerman, S; Williamson, D J; Kaube, H; Goadsby, P J

    2002-01-01

    The detailed pathophysiology of migraine is beginning to be understood and is likely to involve activation of trigeminovascular afferents. Clinically effective anti-migraine compounds are believed to have actions that include peripheral inhibition of calcitonin gene-related peptide (CGRP) release from trigeminal neurones, or preventing dural vessel dilation, or both. CGRP antagonists can block both neurogenic and CGRP-induced dural vessel dilation. Nitric oxide (NO) can induce headache in migraine patients and often triggers a delayed migraine. The initial headache is thought to be caused via a direct action of the NO–cGMP pathway that causes vasodilation by vascular smooth muscle relaxation, while the delayed headache is likely to be a result of triggering trigeminovascular activation. Nitric oxide synthase (NOS) inhibitors are effective in the treatment of acute migraine. The present studies used intravital microscopy to examine the effects of specific NOS inhibitors on neurogenic dural vasodilation (NDV) and CGRP-induced dilation. The non-specific and neuronal NOS (nNOS) inhibitors were able to partially inhibit NDV, while the non-specific and endothelial NOS (eNOS) inhibitors were able to partially inhibit the CGRP induced dilation. There was no effect of the inducible NOS (iNOS) inhibitor. The data suggest that the delayed headache response triggered by NO donors in humans may be due, in part, to increased nNOS activity in the trigeminal system that causes CGRP release and dural vessel dilation. Further, eNOS activity in the endothelium causes NO production and smooth muscle relaxation by direct activation of the NO–cGMP pathway, and may be involved in the initial headache response. PMID:12183331

  5. Model boiler testing to evaluate inhibitors for caustic induced stress corrosion cracking of Alloy 600 tubes

    SciTech Connect

    Daret, J.; Paine, J.P.N.; Partridge, M.J.

    1995-12-31

    A series of model boiler tests, using a mixture of precracked and non-precracked (virgin) tube-to-tube support plate intersections was performed. The testing supported the qualification of inhibitors for mitigating the secondary side corrosion of alloy 600 steam generator tubes. Many utilities suspect that the caustic impurities come from the feedwater. Candidate inhibitors included boric acid (as a reference), cerous acetate, and two forms of titanium dioxide: a laboratory produced titania-silica sol-gel, and manometer sized anatase The latter was combined with a 150 C pre-soaking with a titanium lactate, and was tested with and without a zeta potential treatment by sodium aluminate. Effectiveness of boric acid to prevent and retard caustic induced intergranular corrosion was confirmed in all crevice configurations (open and packed). The cerous acetate treatment multiplied by two to four the time necessary to detect a primary-to-secondary leak on virgin tubes, and reduced the propagation rate on precracked tubes. Cerium was found intimately mixed, as cerianite, with the free span and crevice deposits, when the crevices were sufficiently accessible. Due to its very low solubility and large particle size, the titania-silica sol-gel was unable to penetrate the crevices and had no effect on the degradation process. The nanometric particle size titania treatment and/or the preceding soaking with soluble titanium lactate drastically increased the titanium concentration in free span and open crevice deposit (with no added sodium aluminate, titania reacted with magnetite to form ilmenite) and showed undeniable capacity to prevent tubing degradation. Its effectiveness, in the case of packed crevices and for arresting cracks, was not so conclusive.

  6. Dietary Inulin Fibers Prevent Proton-Pump Inhibitor (PPI)-Induced Hypocalcemia in Mice

    PubMed Central

    Hess, Mark W.; de Baaij, Jeroen H. F.; Gommers, Lisanne M. M.; Hoenderop, Joost G. J.; Bindels, René J. M.

    2015-01-01

    Background Proton-pump inhibitor-induced hypomagnesemia (PPIH) is the most recognized side effect of proton-pump inhibitors (PPIs). Additionally, PPIH is associated with hypocalcemia and hypokalemia. It is hypothesized that PPIs reduce epithelial proton secretion and thereby increase the pH in the colon, which may explain the reduced absorption of and Mg2+ and Ca2+. Fermentation of dietary oligofructose-enriched inulin fibers by the microflora leads to acidification of the intestinal lumen and by this enhances mineral uptake. This study aimed, therefore, to improve mineral absorption by application of dietary inulin to counteract PPIH. Methods Here, C57BL/J6 mice were supplemented with omeprazole and/or inulin. Subsequently, Mg2+ and Ca2+ homeostasis was assessed by means of serum, urine and fecal electrolyte measurements. Moreover, the mRNA levels of magnesiotropic and calciotropic genes were examined in the large intestine and kidney by real-time PCR. Results Treatment with omeprazole significantly reduced serum Mg2+ and Ca2+ levels. However, concomitant addition of dietary inulin fibers normalized serum Ca2+ but not serum Mg2+ concentrations. Inulin abolished enhanced expression of Trpv6 and S100g in the colon by omeprazole. Additionally, intestinal and renal mRNA levels of the Trpm6 gene were reduced after inulin intake. Conclusions This study suggests that dietary inulin counteracts reduced intestinal Ca2+ absorption upon PPI treatment. In contrast, inulin did not increase intestinal absorption of Mg2+ sufficiently to recover serum Mg2+. The clinical potential of dietary inulin treatment should be the subject of future studies. PMID:26397986

  7. Topoisomerase I inhibitor, camptothecin, induces apoptogenic signaling in human embryonic stem cells.

    PubMed

    García, Carolina Paola; Videla Richardson, Guillermo Agustín; Romorini, Leonardo; Miriuka, Santiago Gabriel; Sevlever, Gustavo Emilio; Scassa, María Elida

    2014-03-01

    Embryonic stem cells (ESCs) need to maintain their genomic integrity in response to DNA damage to safeguard the integrity of the organism. DNA double strand breaks (DSBs) are one of the most lethal forms of DNA damage and, if not repaired correctly, they can lead to cell death, genomic instability and cancer. How human ESCs (hESCs) maintain genomic integrity in response to agents that cause DSBs is relatively unclear. In the present study we aim to determine the hESC response to the DSB inducing agent camptothecin (CPT). We find that hESCs are hypersensitive to CPT, as evidenced by high levels of apoptosis. CPT treatment leads to DNA-damage sensor kinase (ATM and DNA-PKcs) phosphorylation on serine 1981 and serine 2056, respectively. Activation of ATM and DNA-PKcs was followed by histone H2AX phosphorylation on Ser 139, a sensitive reporter of DNA damage. Nuclear accumulation and ATM-dependent phosphorylation of p53 on serine 15 were also observed. Remarkably, hESC viability was further decreased when ATM or DNA-PKcs kinase activity was impaired by the use of specific inhibitors. The hypersensitivity to CPT treatment was markedly reduced by blocking p53 translocation to mitochondria with pifithrin-μ. Importantly, programmed cell death was achieved in the absence of the cyclin dependent kinase inhibitor, p21(Waf1), a bona fide p53 target gene. Conversely, differentiated hESCs were no longer highly sensitive to CPT. This attenuated apoptotic response was accompanied by changes in cell cycle profile and by the presence of p21(Waf1). The results presented here suggest that p53 has a key involvement in preventing the propagation of damaged hESCs when genome is threatened. As a whole, our findings support the concept that the phenomenon of apoptosis is a prominent player in normal embryonic development. PMID:24380814

  8. A phase 3 tRial comparing capecitabinE in combination with SorafenIb or pLacebo for treatment of locally advanced or metastatIc HER2-Negative breast CancEr (the RESILIENCE study): study protocol for a randomized controlled trial

    PubMed Central

    2013-01-01

    Background Sorafenib is an oral multikinase inhibitor with antiangiogenic/antiproliferative activity. A randomized phase 2b screening trial in human epidermal growth factor receptor 2 (HER2)-negative advanced breast cancer demonstrated a significant improvement in progression-free survival (PFS) when sorafenib was added to capecitabine versus placebo (median 6.4 versus 4.1 months; hazard ratio = 0.58; P = 0.001). Most drug-related adverse events were Grade 1/2 in severity with the exception of Grade 3 hand-foot skin reaction/syndrome (44% versus 14%, respectively). These results suggest a role for the combination of sorafenib and capecitabine in breast cancer and supported a phase 3 confirmatory trial. Here we describe RESILIENCE - a multinational, double-blind, randomized, placebo-controlled, phase 3 trial - assessing the addition of sorafenib to first- or second-line capecitabine in advanced HER2-negative breast cancer. Methods/design Eligibility criteria include ≥18 years of age, ≤1 prior chemotherapy regimen for metastatic disease, and resistant to/failed taxane and anthracycline or no indication for further anthracycline. Prior treatment with a vascular endothelial growth factor inhibitor is not allowed. Patients with significant cardiovascular disease or active brain metastases are not eligible. Patients are stratified by hormone-receptor status, geographic region, and prior metastatic chemotherapy status and randomized (1:1) to capecitabine (1000 mg/m2 orally twice daily (BID), days 1 to 14 of 21) in combination with sorafenib (orally BID, days 1 to 21, total dose 600 mg/day) or matching placebo. Capecitabine and sorafenib/placebo doses can be escalated to 1250 mg/m2 BID and 400 mg BID, respectively, as tolerated, or reduced to manage toxicity. Dose re-escalation after a reduction is allowed for sorafenib/placebo but not for capecitabine. This dosing algorithm was designed to mitigate dermatologic and other toxicity, in addition to detailed guidelines

  9. Long-term outcomes of patients with advanced hepatocellular carcinoma who achieved complete remission after sorafenib therapy

    PubMed Central

    2015-01-01

    Background/Aims Sorafenib is currently the sole molecular targeted agent that improves overall survival in advanced hepatocellular carcinoma (HCC). Despite the efficacy of sorafenib, the response rate varies in patients with advanced HCC. We retrospectively analyzed a series of Korean patients with advanced HCC with complete remission (CR) after sorafenib therapy. Methods In total, 523 patients with advanced HCC were treated with sorafenib in 3 large tertiary referral hospitals in Korea. A survey was conducted to collect data on patients who experienced CR after sorafenib monotherapy, and their medical records and follow-up data were analyzed. The tumor response and recurrence rates were assessed by radiologic study, based on modified response evaluation criteria in solid tumors. Results Seven patients with advanced HCC experienced CR after sorafenib therapy. The median time to tumor disappearance and the median disease-free survival time were 3 months and 9 months, respectively. HCC recurrence was identified in three cases (42.9%). Of these, two patients discontinued sorafenib before or after achieving CR and the other patient continued sorafenib after achieving CR. HCC recurred at 3, 10, and 42 months after CR in these three patients. Three patients needed dose reduction for toxicity and adverse events. Conclusions Though CR was achieved after sorafenib therapy in patients with advanced HCC, the recurrence rate was relatively high. Subsequent strategies to reduce a chance of recurrence after sorafenib therapy are required to investigate. PMID:26527250

  10. Tyrosine Kinase Inhibitors Induce Down-Regulation of c-Kit by Targeting the ATP Pocket

    PubMed Central

    Descarpentries, Clotilde; Frisan, Emilie; Adam, Kevin; Verdier, Frederique; Floquet, Célia; Dubreuil, Patrice; Lacombe, Catherine; Fontenay, Michaela; Mayeux, Patrick; Kosmider, Olivier

    2013-01-01

    The stem cell factor receptor (SCF) c-Kit plays a pivotal role in regulating cell proliferation and survival in many cell types. In particular, c-Kit is required for early amplification of erythroid progenitors, while it must disappear from cell surface for the cell entering the final steps of maturation in an erythropoietin-dependent manner. We initially observed that imatinib (IM), an inhibitor targeting the tyrosine kinase activity of c-Kit concomitantly down-regulated the expression of c-Kit and accelerated the Epo-driven differentiation of erythroblasts in the absence of SCF. We investigated the mechanism by which IM or related masitinib (MA) induce c-Kit down-regulation in the human UT-7/Epo cell line. We found that the down-regulation of c-Kit in the presence of IM or MA was inhibited by a pre-incubation with methyl-β-cyclodextrin suggesting that c-Kit was internalized in the absence of ligand. By contrast to SCF, the internalization induced by TKI was independent of the E3 ubiquitin ligase c-Cbl. Furthermore, c-Kit was degraded through lysosomal, but not proteasomal pathway. In pulse-chase experiments, IM did not modulate c-Kit synthesis or maturation. Analysis of phosphotyrosine peptides in UT-7/Epo cells treated or not with IM show that IM did not modify overall tyrosine phosphorylation in these cells. Furthermore, we showed that a T670I mutation preventing the full access of IM to the ATP binding pocket, did not allow the internalization process in the presence of IM. Altogether these data show that TKI-induced internalization of c-Kit is linked to a modification of the integrity of ATP binding pocket. PMID:23637779

  11. Trichostatin A, a histone deacetylase inhibitor, modulates unloaded-induced skeletal muscle atrophy.

    PubMed

    Dupré-Aucouturier, Sylvie; Castells, Josiane; Freyssenet, Damien; Desplanches, Dominique

    2015-08-15

    Skeletal muscle atrophy is commonly associated with immobilization, ageing, and catabolic diseases such as diabetes and cancer cachexia. Epigenetic regulation of gene expression resulting from chromatin remodeling through histone acetylation has been implicated in muscle disuse. The present work was designed to test the hypothesis that treatment with trichostatin A (TSA), a histone deacetylase inhibitor, would partly counteract unloading-induced muscle atrophy. Soleus muscle atrophy (-38%) induced by 14 days of rat hindlimb suspension was reduced to only 25% under TSA treatment. TSA partly prevented the loss of type I and IIa fiber size and reversed the transitions of slow-twitch to fast-twitch fibers in soleus muscle. Unloading or TSA treatment did not affect myostatin gene expression and follistatin protein. Soleus protein carbonyl content remained unchanged, whereas the decrease in glutathione vs. glutathione disulfide ratio and the increase in catalase activity (biomarkers of oxidative stress) observed after unloading were abolished by TSA treatment. The autophagy-lysosome pathway (Bnip3 and microtubule-associated protein 1 light chain 3 proteins, Atg5, Gabarapl1, Ulk1, and cathepsin B and L mRNA) was not activated by unloading or TSA treatment. However, TSA suppressed the rise in muscle-specific RING finger protein 1 (MuRF1) caused by unloading without affecting the forkhead box (Foxo3) transcription factor. Prevention of muscle atrophy by TSA might be due to the regulation of the skeletal muscle atrophy-related MuRF1 gene. Our findings suggest that TSA may provide a novel avenue to treat unloaded-induced muscle atrophy. PMID:26112243

  12. Xanthine crystals induced by topiroxostat, a xanthine oxidoreductase inhibitor, in rats, cause transitional cell tumors.

    PubMed

    Shimo, Takeo; Moto, Mitsuyoshi; Ashizawa, Naoki; Matsumoto, Koji; Iwanaga, Takashi; Saito, Kazuhiro

    2014-04-01

    The present study was performed to elucidate the underlying mechanism of transitional cell tumors found in the carcinogenicity testing of topiroxostat, a xanthine oxidoreductase inhibitor, in which topiroxostat was orally given to F344 rats at 0.3, 1, and 3 mg/kg for 2 years. In the urinary bladder, transitional cell papillomas and/or carcinomas were seen in males receiving 0.3, 1, and 3 mg/kg (1/49, 3/49, and 10/50, respectively). In the kidney, transitional cell papillomas and/or carcinomas in the pelvis were seen in 2/50 males and 1/50 females receiving 3 mg/kg. In the mechanistic study by 52-week oral treatment with topiroxostat at 3 mg/kg to F344 male rats, with and without citrate, simple and papillary transitional cell hyperplasias of the urinary bladder epithelium were observed in 5/17 in the topiroxostat-alone treatment group, along with xanthine-induced nephropathy, in contrast to neither xanthine crystals nor lesions in urinary organs by co-treatment group with citrate. As for sex differences of urinary bladder tumors, the BrdU labeling index for epithelial cells of the urinary bladder by 5-week oral treatment with topiroxostat at 10 mg/kg to F344 rats was increased in males only, showing consistency with histopathological findings. Therefore, the present study indicates that transitional cell tumors induced by topiroxostat in rats were due to physical stimulation to transitional cells of xanthine crystals/calculi and provides that other factors were not implicated in this tumorigenesis. Furthermore, the present study suggests that such tumors do not predict for humans since topiroxostat-induced xanthine deposition is a rodent-specific event. PMID:24448833

  13. Epilepsy and hippocampal neurodegeneration induced by glutamate decarboxylase inhibitors in awake rats.

    PubMed

    Salazar, Patricia; Tapia, Ricardo

    2015-10-01

    Glutamic acid decarboxylase (GAD), the enzyme responsible for GABA synthesis, requires pyridoxal phosphate (PLP) as a cofactor. Thiosemicarbazide (TSC) and γ-glutamyl-hydrazone (PLPGH) inhibit the free PLP-dependent isoform (GAD65) activity after systemic administration, leading to epilepsy in mice and in young, but not in adult rats. However, the competitive GAD inhibitor 3-mercaptopropionic acid (MPA) induces convulsions in both immature and adult rats. In the present study we tested comparatively the epileptogenic and neurotoxic effects of PLPGH, TSC and MPA, administered by microdialysis in the hippocampus of adult awake rats. Cortical EEG and motor behavior were analyzed during the next 2h, and aspartate, glutamate and GABA were measured by HPLC in the microdialysis-collected fractions. Twenty-four hours after drug administration rats were fixed for histological analysis of the hippocampus. PLPGH or TSC did not affect the motor behavior, EEG or cellular morphology, although the extracellular concentration of GABA was decreased. In contrast, MPA produced intense wet-dog shakes, EEG epileptiform discharges, a >75% reduction of extracellular GABA levels and remarkable neurodegeneration of the CA1 region, with >80% neuronal loss. The systemic administration of the NMDA glutamate receptor antagonist MK-801 30 min before MPA did not prevent the MPA-induced epilepsy but significantly protected against its neurotoxic effect, reducing neuronal loss to <30%. We conclude that in adult awake rats, drugs acting on PLP availability have only a weak effect on GABA neurotransmission, whereas direct GAD inhibition produced by MPA induces hyperexcitation leading to epilepsy and hippocampal neurodegeneration. Because this degeneration was prevented by the blockade of NMDA receptors, we conclude that it is due to glutamate-mediated excitotoxicity consequent to disinhibition of the hippocampal excitatory circuits. PMID:26354164

  14. Simotinib as a modulator of P-glycoprotein: substrate, inhibitor, or inducer?

    PubMed

    Huang, Lingling; Shen, Cheng; Chen, Yanfen; Yan, Huiwen; Cheng, Zeneng; Zhu, Qubo

    2016-04-01

    As a new antitumor drug, simotinib hydrochloride is prescribed for prolonged periods, often to patients with comorbidities. Therefore, the risk for developing drug resistance and drug-drug interactions between simotinib and other agents has to be taken into consideration. As P-glycoprotein (P-gp) is an efflux transporter, which plays a significant role in drug resistance and influences the pharmacological properties and toxicities of the drugs it interacts with, the interactions between simotinib and P-gp were investigated. Cytotoxicity was measured using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay. Intracellular drug concentrations were detected by high-performance liquid chromatography, fluorescence-activated cell sorting and using a fluorescence reader. P-gp ATPase activity was measured using the Pgp-Glo assay, and intracellular pH was assessed using the fluorescent probe 2',7'-bis(2-carboxyethyl)-5(6)-carboxyfluorescein acetoxymethyl. The expression and transcription of P-gp were detected by western blotting and the luciferase assay. Simotinib has no cross-resistance to P-gp substrates, and its efflux rate was independent of either the P-gp expression or the coadministered P-gp substrate. Simotinib reversed chemotherapeutic agent resistance in a short time by increasing the intracellular concentration of the chemotherapeutic agent and blocked rhodamine 123 efflux. Further studies demonstrated that simotinib inhibited P-gp activity by modulating its ATPase activity and the intracellular pH. Although simotinib induced P-gp expression after extended treatment, the induced expression of P-gp had little impact on drug resistance. Simotinib is not a substrate of P-gp. As a modulator, it functions mainly as an inhibitor of P-gp by modulating the intracellular pH and ATPase activity, although it also induces P-gp expression after extended treatment. PMID:26766493

  15. Flavone as PARP-1 inhibitor: its effect on lipopolysaccharide induced gene-expression.

    PubMed

    Geraets, Liesbeth; Moonen, Harald J J; Brauers, Karen; Gottschalk, Ralph W H; Wouters, Emiel F M; Bast, Aalt; Hageman, Geja J

    2007-11-14

    The nuclear enzyme poly(ADP-ribose) polymerase-1 (PARP-1) which was initially known for its role in the repair of oxidative stress-induced DNA damage, has also been reported to play a mediating role in the inflammatory response. Studies with PARP-1 knockout models have shown that PARP-1 is a co-activator of Nuclear Factor-kappa B (NF-kappaB), although this appears not to require its enzyme activity. In addition, drug-induced inhibition of the enzyme activity of PARP-1 was observed to reduce the production of pro-inflammatory mediators. In this study, the flavonoid compound flavone was demonstrated to significantly inhibit the enzyme activity of PARP-1. Further evaluation of flavone in N-methyl-N'-nitro-N-nitrosoguanidine (MNNG)-treated human pulmonary epithelial and vascular endothelial cells revealed that both the decrease in NAD(+) levels, as well as the formation of PAR-polymers was dose-dependently attenuated by flavone. In addition, flavone was found to reduce the lipopolysaccharide (LPS)-induced interleukin (IL)-8 production in pulmonary epithelial cells, which was confirmed by transcription analysis. Furthermore, the transcription Inhibitor kappa B alpha (of IkappaBalpha) was significantly increased by flavone. The results of the present study indicate that the flavonoid flavone could be a potential candidate for application in treatment of chronic inflammatory diseases. PARP-1 inhibition could have beneficial effects in such diseases as Chronic Obstructive Pulmonary Disease (COPD) and diabetes, by preservation of cellular NAD(+) levels and attenuating inflammatory conditions. PMID:17643414

  16. Treatment of sunitinib-induced hypertension in solid tumor by nitric oxide donors.

    PubMed

    León-Mateos, L; Mosquera, J; Antón Aparicio, L

    2015-12-01

    Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) are overexpressed in the majority of renal cell carcinomas. This characteristic has supported the rationale of targeting VEGF-driven tumour vascularization, especially in clear cell RCC. VEGF-inhibiting strategies include the use of tyrosine kinase inhibitors (sunitinib, axitinib, pazopanib, and sorafenib) and neutralizing antibodies such as bevacizumab. Hypertension (HTN) is one of the most common adverse effects of angiogenesis inhibitors. HTN observed in clinical trials appears to correlate with the potency of VEGF kinase inhibitor against VEGFR-2: agents with higher potency are associated with a higher incidence of HTN. Although the exact mechanism by tyrosine kinase inhibitors induce HTN has not yet been completely clarified, two key hypotheses have been postulated. First, some studies have pointed to a VEGF inhibitors-induced decrease in nitric oxide synthase (NOS) and nitric oxide (NO) production, that can result in vasoconstriction and increased blood pressure. VEGF, mediated by PI3K/Akt and MAPK pathway, upregulates the endothelial nitric oxide synthase enzyme leading to up-regulation of NO production. So inhibition of signaling through the VEGF pathway would lead to a decrease in NO production, resulting in an increase in vascular resistance and blood pressure. Secondly a decrease in the number of microvascular endothelial cells and subsequent depletion of normal microvessel density (rarefaction) occurs upon VEGF signaling inhibition. NO donors could be successfully used not only for the treatment of developed angiogenesis-inhibitor-induced hypertension but also for preventive effects. PMID:26386874

  17. Synthesis of thermosensitive magnetic nanocarrier for controlled sorafenib delivery.

    PubMed

    Heidarinasab, Amir; Ahmad Panahi, Homayon; Faramarzi, Mehdi; Farjadian, Fatemeh

    2016-10-01

    Allyl glycidyl ether/N-isopropylacrylamide-grafted magnetic nanoparticles were prepared using silica-coated magnetic nanoparticles as a substrate for radical copolymerization of allyl glycidyl ether and N-isopropylacrylamide. Chitosan was coupled with the prepared nanoparticles by opening the epoxy ring of the allyl glycidyl ether. The thermosensitive magnetic nanocarrier (TSMNC) obtained can be applied as a potent drug carrier. The TSMNC structure was characterized using Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, vibrating sample magnetometer, and elemental analysis. Its morphology and size were investigated using field emission scanning electron microscopy, transmission electron microscopy and dynamic light scattering. The feasibility of employing the TSMNC for adsorption and in vitro controlled release of the chemotherapeutic agent sorafenib was tested. The effect of the adsorption parameters of pH, temperature, and loading time of sorafenib onto TSMNC was evaluated. The adsorption data was fitted to the Langmuir and Freundlich isotherms and the relevant parameters derived. The drug release profile indicated that 88% of the adsorbed drug was released within 35h at 45°C and drug release was Fickian diffusion-controlled. The results confirmed that the TSMNC has a high adsorption capacity at low temperature and good controlled release in a slow rate at a high temperature and could be developed for further application as a drug nanocarrier. PMID:27287097

  18. The hsp70 inhibitor VER155008 induces paraptosis requiring de novo protein synthesis in anaplastic thyroid carcinoma cells.

    PubMed

    Kim, Si Hyoung; Kang, Jun Goo; Kim, Chul Sik; Ihm, Sung-Hee; Choi, Moon Gi; Yoo, Hyung Joon; Lee, Seong Jin

    2014-11-01

    In this study, we evaluated the effect of the hsp70 inhibitor VER155008 on survival of anaplastic thyroid carcinoma (ATC) cells. In ATC cells, VER155008 increased the percentages of dead cells and vacuolated cells. VER155008 did not lead to the cleavage of caspase-3 protein regardless of pretreatment with z-VAD-fmk. VER155008 increased LC3-II protein levels but the protein levels were not changed by autophagy inhibitors. VER155008 caused the dilatation of endoplasmic reticulum (ER), and the increased mRNA levels of Bip and CHOP, suggesting paraptosis. VER155008-induced paraptosis was attenuated by pretreatment with cycloheximide. In conclusion, VER155008 induces paraptosis characterized by cytoplasmic vacuolation, independence of caspase, dilatation of ER and induction of ER stress markers in ATC cells. Moreover, VER155008-induced paraptosis requires de novo protein synthesis in ATC cells. PMID:25450359

  19. Nucleoside Reverse Transcriptase Inhibitors Suppress Laser-Induced Choroidal Neovascularization in Mice

    PubMed Central

    Mizutani, Takeshi; Fowler, Benjamin J.; Kim, Younghee; Yasuma, Reo; Krueger, Laura A.; Gelfand, Bradley D.; Ambati, Jayakrishna

    2015-01-01

    Purpose To evaluate the efficacy of nucleoside reverse transcriptase inhibitors (NRTIs) in the laser-induced mouse model of choroidal neovascularization (CNV). Methods We evaluated the NRTIs lamivudine (3TC), zidovudine (AZT), and abacavir (ABC) and the P2X7 antagonist A438079. Choroidal neovascularization was induced by laser injury in C57BL/6J wild-type, Nlrp3−/−, and P2rx7−/− mice, and CNV volume was measured after 7 days by confocal microscopy. Drugs were administered by intravitreous injection immediately after the laser injury. Vascular endothelial growth factor-A in RPE-choroid lysates was measured 3 days after laser injury by ELISA. HEK293 cells expressing human and mouse P2X7 were exposed to the selective P2X7 receptor agonist 2′, 3′-(benzoyl-4-benzoyl)-ATP (Bz-ATP) with or without 3TC, and VEGF-A levels in media were measured by ELISA. Results Intravitreous injection of 3TC, AZT, and ABC significantly suppressed laser-induced CNV in C57BL/6J wild-type and Nlrp3−/− mice (P < 0.05) but not in P2rx7−/− mice. Intravitreous injection of A438079 also suppressed the laser-induced CNV (P < 0.05). The NRTIs 3TC, AZT, and ABC blocked VEGF-A levels in the RPE/choroid after laser injury in wild-type (P < 0.05) but not P2rx7−/− mice. Moreover, there was no additive effect of 3TC on CNV inhibition when coadministered with a neutralizing VEGF-A antibody. Stimulation of human and mouse P2X7-expressing HEK293 cells with Bz-ATP increased VEGF secretion (P < 0.001), which was abrogated by 3TC (P < 0.001). Stimulation of primary human RPE cells with Bz-ATP increased VEGFA and IL6 mRNA levels, which were abrogated by 3TC. Conclusions Multiple clinically relevant NRTIs suppressed laser-induced CNV and downregulated VEGF-A, via P2X7. PMID:26529046

  20. Histone deacetylase inhibitors suppress RSV infection and alleviate virus-induced airway inflammation.

    PubMed

    Feng, Qiuqin; Su, Zhonglan; Song, Shiyu; Χu, Hui; Zhang, Bin; Yi, Long; Tian, Man; Wang, Hongwei

    2016-09-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants and young children. However, the majority of RSV-infected patients only show mild symptoms. Different severities of infection and responses among the RSV-infected population indicate that epigenetic regulation as well as personal genetic background may affect RSV infectivity. Histone deacetylase (HDAC) is an important epigenetic regulator in lung diseases. The present study aimed to explore the possible connection between HDAC expression and RSV-induced lung inflammation. To address this question, RSV-infected airway epithelial cells (BEAS‑2B) were prepared and a mouse model of RSV infection was established, and then treated with various concentrations of HDAC inhibitors (HDACis), namely trichostatin A (TSA) and suberoylanilide hydroxamic acid (SAHA). Viral replication and markers of virus-induced airway inflammation or oxidative stress were assessed. The activation of the nuclear factor-κB (NF-κB), cyclo-oxygenase-2 (COX-2), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription 3 (STAT3) signaling pathways was evaluated by western blot analysis. Our results showed that RSV infection in airway epithelial cells (AECs) significantly decreased histone acetylation levels by altering HDAC2 expression. The treatment of RSV-infected AECs with HDACis significantly restricted RSV replication by upregulating the interferon-α (IFN-α) related signaling pathways. The treatment of RSV-infected AECs with HDACis also significantly inhibited RSV-induced pro-inflammatory cytokine release [interleukin (IL)-6 and IL-8] and oxidative stress-related molecule production [malondialdehyde (MDA), and nitrogen monoxide (NO)]. The activation of NF-κB, COX-2, MAPK and Stat3, which orchestrate pro‑inflammatory gene expression and oxidative stress injury, was also significantly inhibited. Our in vivo study using a mouse model of

  1. Histone deacetylase inhibitors suppress RSV infection and alleviate virus-induced airway inflammation

    PubMed Central

    Feng, Qiuqin; Su, Zhonglan; Song, Shiyu; Xu, Hui; Zhang, Bin; Yi, Long; Tian, Man; Wang, Hongwei

    2016-01-01

    Respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants and young children. However, the majority of RSV-infected patients only show mild symptoms. Different severities of infection and responses among the RSV-infected population indicate that epigenetic regulation as well as personal genetic background may affect RSV infectivity. Histone deacetylase (HDAC) is an important epigenetic regulator in lung diseases. The present study aimed to explore the possible connection between HDAC expression and RSV-