Isolation and characterization of endophytic taxol-producing fungi from Taxus chinensis.

PubMed

Liu, Kaihui; Ding, Xiaowei; Deng, Baiwan; Chen, Wenqiang

2009-09-01

This study investigated the endophytic fungi diversity of Taxus chinensis and screened the taxol-producing fungi in the host. A total of 115 endophytic fungi isolates obtained from bark segments of T. chinensis were grouped into 23 genera based on the morphological traits and sequence analysis of the internal transcribed spacers (ITS1-5.8S-ITS2), indicating endophytic fungi in T. chinensis are diverse and abundant. Diaporthe, Phomopsis (anamorph of Diaporthe), Acremonium, and Pezicula were the dominant genera, whereas the remaining genera were infrequent groups. The 13 representative species of the distinct genera were capable of producing taxol verified by reverse-phase high performance liquid chromatography (HPLC). Among the taxol-producing fungi, the yield of taxol produced by the Metarhizium anisopliae, H-27 was 846.1 microg l(-1) in reformative potato dextrose liquid medium, and the fungal taxol was further validated by mass spectrometry (MS). The taxol-producing fungi (92.3%) were infrequent communities, suggesting that infrequent fungi associated with T. chinensis might be a fascinating reservoir of taxol-generating fungi.

Occurrence of taxol and related taxanes in the wood of Pacific yew

Treesearch

John R. Obst

1993-01-01

Maximizing the yield of taxol per tree is important for the best management of the yew resource. Therefore, the possibility of obtaining additional taxol from the wood was explored. Initial reports form our laboratory, in cooperation with the National Cancer Institute, indicated relatively high concentrations of taxol in Pacific yew heartwood. Although these taxol...

A new large-scale process for taxol and related taxanes from Taxus brevifolia.

PubMed

Rao, K V; Hanuman, J B; Alvarez, C; Stoy, M; Juchum, J; Davies, R M; Baxley, R

1995-07-01

In view of the demonstrated antitumor activity of taxol, ready availability of the drug is important. The current isolation methods starting from the bark of Taxus brevifolia involve multiple manipulations, leading to only taxol and in a yield of 0.01%. A new process consisting of a single reverse phase column is introduced here, and the present purpose is to determine its large scale applicability. The chloroform extractable fraction of the bark of T. brevifolia is applied directly on to a C-18 bonded silica column in 25% acetonitrile/water, with elution using a step gradient: 30-50% acetonitrile/water. On standing, eight different taxanes, including taxol, crystallize out directly from different fractions. The crystals are filtered and purified further by recrystallization. Taxol and four other taxanes are purified this way. The other three require a short silica column. Taxol is freed from cephalomannine by selective ozonolysis. The large scale process gave taxol (0.04%), 10-deacetylbaccatin III (0.02%), 10-deacetyl taxol-7-xyloside (0.1%), 10-deacetyl taxol-C-7-xyloside (0.04%), 10-deacetyl cephalomannine-7-xyloside (0.006%), taxol-7-xyloside (0.008%), 10-deacetyl taxol (0.008%) and cephalomannine (0.004%). Processing of the needles of T. brevifolia gave brevifoliol (0.17%), and that of the wood, 10-deacetyl taxol-C-7-xyloside (0.01%) and 10-deacetyl taxol-C. The reverse phase column process is simpler (one column, direct crystallization), more efficient (eight taxanes obtained simultaneously) and also gives higher yields.

Insulin-Like Growth Factor 2 Silencing Restores Taxol Sensitivity in Drug Resistant Ovarian Cancer

PubMed Central

Brouwer-Visser, Jurriaan; Lee, Jiyeon; McCullagh, KellyAnne; Cossio, Maria J.; Wang, Yanhua; Huang, Gloria S.

2014-01-01

Drug resistance is an obstacle to the effective treatment of ovarian cancer. We and others have shown that the insulin-like growth factor (IGF) signaling pathway is a novel potential target to overcome drug resistance. The purpose of this study was to validate IGF2 as a potential therapeutic target in drug resistant ovarian cancer and to determine the efficacy of targeting IGF2 in vivo. An analysis of The Cancer Genome Atlas (TCGA) data in the serous ovarian cancer cohort showed that high IGF2 mRNA expression is significantly associated with shortened interval to disease progression and death, clinical indicators of drug resistance. In a genetically diverse panel of ovarian cancer cell lines, the IGF2 mRNA levels measured in cell lines resistant to various microtubule-stabilizing agents including Taxol were found to be significantly elevated compared to the drug sensitive cell lines. The effect of IGF2 knockdown on Taxol resistance was investigated in vitro and in vivo. Transient IGF2 knockdown significantly sensitized drug resistant cells to Taxol treatment. A Taxol-resistant ovarian cancer xenograft model, developed from HEY-T30 cells, exhibited extreme drug resistance, wherein the maximal tolerated dose of Taxol did not delay tumor growth in mice. Blocking the IGF1R (a transmembrane receptor that transmits signals from IGF1 and IGF2) using a monoclonal antibody did not alter the response to Taxol. However, stable IGF2 knockdown using short-hairpin RNA in HEY-T30 effectively restored Taxol sensitivity. These findings validate IGF2 as a potential therapeutic target in drug resistant ovarian cancer and show that directly targeting IGF2 may be a preferable strategy compared with targeting IGF1R alone. PMID:24932685

Taxol induces concentration-dependent phosphatidylserine (PS) externalization and cell cycle arrest in ASTC-a-1 cells

NASA Astrophysics Data System (ADS)

Guo, Wen-jing; Chen, Tong-sheng

2010-02-01

Taxol (Paclitaxel) is an important natural product for the treatment of solid tumors. Different concentrations of taxol can trigger distinct effects on both the cellular microtubule network and biochemical pathways. Apoptosis induced by low concentrations (5-30 nM) of taxol was associated with mitotic arrest, alteration of microtubule dynamics and/or G2/M cell cycle arrest, whereas high concentrations of this drug (0.2-30 μM) caused significant microtubule damage, and was found recently to induce cytoplasm vacuolization in human lung adenocarcinoma (ASTC-a-1) cells. In present study, cell counting kit (CCK-8) assay, confocal microscope, and flow cytometry analysis were used to analyze the cell death form induced by 35 nM and 70 μM of taxol respectively in human lung adenocarcinoma (ASTC-a-1) cells. After treatment of 35 nM taxol for 48 h, the OD450 value was 0.80, and 35 nM taxol was found to induce dominantly cell death in apoptotic pathway such as phosphatidylserine (PS) externalization, G2/M phase arrest after treatment for 24 h, and nuclear fragmentation after treatment for 48 h. After 70 μM taxol treated the cell for 24 h, the OD450 value was 1.01, and 70 μM taxol induced cytoplasm vacuolization programmed cell death (PCD) and G2/M phase as well as the polyploidy phase arrest in paraptotic-like cell death. These findings imply that the regulated signaling pathway of cell death induced by taxol is dependent on taxol concentration in ASTC-a-1 cells.

Effect of taxol from Pestalotiopsis mangiferae on A549 cells-In vitro study.

PubMed

Kathiravan, Govindarajan; Sureban, Sripathi M

2009-12-01

Pestalotiopsis mangiferae Coelomycete fungi were used to examine the production of taxol. The taxol isolated from this fungus is biologically active against cancer cell lines were investigated for its antiproliferative activity in human Non Small Cell Lung Cancer A549 cells. The results showed that the methylene chloride extraction of Pestalotiopsis mangiferae inhibited the proliferation of A 549 cells as measured by MTT and Trypan blue assay. Flow cytometric analysis showed that methylene chloride extraction of Pestalotiopsis mangiferae blocked cell cycle progression in G0/G1 phase. In addition fungal taxol induced A549 cell apoptosis as determined by propidium iodide staining. Further the percentage of LDH release was increased at increasing concentrations which is a measure of cell death. The levels of sialic acid levels and DNA, RNA and protein levels were decreased after treatment with methylene chloride extraction of Pestalotiopsis mangiferae. We suggests that methylene chloride extraction of Pestalotiopsis mangiferae might be considered for future therapeutic application with further studies against lung cancer.

[Clinical efficacy and adverse effects of taxol plus carboplatin or gemcitabine plus carboplatin in patients with advanced non-small-cell lung carcinoma].

PubMed

Wang, Xiao-Yun; Zhao, Yu-Liang

2010-12-21

To observe the clinical efficacy and adverse effects of taxol plus carboplatin (TP) or gemcitabine plus carboplatin (GP) in patients with advanced non-small-cell lung carcinoma. A total of 86 patients with advanced non-small-cell lung carcinoma with a histologically confirmed diagnosis at our department were treated with at least two cycles of drug therapy according to the WHO standard. There were 43 cases in TP group and 43 cases in GP group. TP group: taxol 150 mg/m(2), d1, carboplatin 300 mg/m(2) in d1; GP group: gemcitabine 1000 mg/m(2), 30 min, d1, 8, carboplatin 300 mg/m(2) in d1, 3 weeks a cycle. The efficacy and side effects were analyzed after two cycles of chemotherapy. When TP and GP groups were compared, the effective rate was 44.2% vs 39.5%; disease control rate (CR + PR + SD): 81.4% vs 74.4%; median time to progress (TTP): 4.6 vs 4.5 months; medium survivals: 8.6 vs 8.8 months; 1-year survival rates: 17.2% vs 18.1%; 2-year survival rates: 8% vs 10%. The statistic analysis showed that the two groups had no significant difference. The main cytotoxicities of GP and TP groups were predominantly thrombocytopenia and leucopenia respectively. The two groups had no significant statistical difference. The incidences of allergen, alopecia and peripheral neurotoxicity were higher in the TP group. The two groups had statistical difference. Tolerance was excellent in both groups. The therapeutic effect and tolerance are excellent for advanced non-small cell lung carcinoma. The efficacy and survival rate of two groups show no statistical difference.

Transcriptome-wide identification and screening of WRKY factors involved in the regulation of taxol biosynthesis in Taxus chinensis.

PubMed

Zhang, Meng; Chen, Ying; Nie, Lin; Jin, Xiaofei; Liao, Weifang; Zhao, Shengying; Fu, Chunhua; Yu, Longjiang

2018-03-26

WRKY, a plant-specific transcription factor family, plays important roles in pathogen defense, abiotic cues, phytohormone signaling, and regulation of plant secondary metabolism. However, little is known about the roles, functions, and mechanisms of WRKY in taxane biosynthesis in Taxus spp. In this study, 61 transcripts were identified from Taxus chinensis transcriptome datasets by using hidden Markov model search. All of these transcripts encoded proteins containing WRKY domains, which were designated as TcWRKY1-61. After phylogenetic analysis of the WRKY domains of TcWRKYs and AtWRKYs, 16, 8, 10, 14, 5, 7, and 1 TcWRKYs were cladded into Group I, IIa-IIe, and III, respectively. Then, six representative TcWRKYs were selected to classify their effects on taxol biosynthesis. After MeJA (methyl jasmonate acid) and SA (salicylic acid) treatments, all of the six TcWRKYs were upregulated by MeJA treatment. TcWRKY44 (IId) and TcWRKY47 (IIa) were upregulated, whereas TcWRKY8 (IIc), TcWRKY20 (III), TcWRKY26 (I), TcWRKY41 (IIe), and TcWRKY52 (IIb) were downregulated by SA treatment. Overexpression experiments showed that the six selected TcWRKYs exerted different effects on taxol biosynthesis. In specific, TcWRKY8 and TcWRKY47 significantly improved the expression levels of taxol-biosynthesis-related genes. Transcriptome-wide identification of WRKY factors in Taxus not only enhances our understanding of plant WRKY factors but also identifies candidate regulators of taxol biosynthesis.

Evaluation of anticancer effects and enhanced doxorubicin cytotoxicity of xanthine derivatives using canine hemangiosarcoma cell lines.

PubMed

Motegi, Tomoki; Katayama, Masaaki; Uzuka, Yuji; Okamura, Yasuhiko

2013-10-01

Methylxanthine derivatives increase cAMP and are known to have diuretic, cardiac, and central nervous system stimulatory effects. Moreover, caffeine inhibits the development of tumors induced by various carcinogens. The aim of this work was to elucidate the anticancer effects on apoptosis of xanthine derivatives alone and with doxorubicin in canine hemangiosarcoma cells. Xanthine derivatives with or without doxorubicin were administered to cells, and the effects were investigated by measuring tumor cell proliferation, cell death (cytotoxicity) induction, and apoptosis by the expression of annexin V or caspase 3/7. Both caffeine and theophylline induced apoptosis, and the treated cells expressed annexin V and caspase 3/7. Both drugs enhanced doxorubicin-induced cytotoxicity; however, hypoxanthine showed no effect. These results indicate that theophylline is similar to caffeine; both drugs may enhance doxorubicin-induced cytotoxicity by inhibiting ATM/ATR kinases. Our data suggest that caffeine and theophylline have anticancer effects and can improve the treatment effect in canine hemangiosarcoma patients. Copyright © 2013 Elsevier Ltd. All rights reserved.

Live morphological analysis of taxol-induced cytoplasmic vacuolization [corrected] in human lung adenocarcinoma cells.

PubMed

Wang, Xiao-Ping; Chen, Tong-Sheng; Sun, Lei; Cai, Ji-Ye; Wu, Ming-Qian; Mok, Martin

2008-12-01

Taxol (paclitaxel), one of the most active cancer chemotherapeutic agents, can cause programmed cell death (PCD) and cytoplasmic vacuolization. The objective of this study was to analyze the morphological characteristics induced by taxol. Human lung adenocarcinoma (ASTC-a-1) cells were exposed to various concentration of taxol. CCK-8 was used to assay the cell viability. Atomic force microscopy (AFM), plasmid transfection and confocal fluorescence microscopy were performed to image the cells morphological change induced by taxol. Fluorescence resonance energy transfer (FRET) was used to monitor the caspase-3 activation in living cells during taxol-induced cell death. Cells treated with taxol exhibited significant swelling and cytoplasmic vacuolization which may be due to endoplasmic reticulum (ER) vacuolization. Caspase-3 was not activated during taxol-induced cytoplasmic vacuolization and cell death. These findings suggest that taxol induces caspase-3-independent cytoplasmic vacuolization, cell swelling and cell death through ER vacuolization.

Effect of taxol from Pestalotiopsis mangiferae on A549 cells-In vitro study

PubMed Central

Kathiravan, Govindarajan; Sureban, Sripathi M.

2009-01-01

Pestalotiopsis mangiferae Coelomycete fungi were used to examine the production of taxol. The taxol isolated from this fungus is biologically active against cancer cell lines were investigated for its antiproliferative activity in human Non Small Cell Lung Cancer A549 cells. The results showed that the methylene chloride extraction of Pestalotiopsis mangiferae inhibited the proliferation of A 549 cells as measured by MTT and Trypan blue assay. Flow cytometric analysis showed that methylene chloride extraction of Pestalotiopsis mangiferae blocked cell cycle progression in G0/G1 phase. In addition fungal taxol induced A549 cell apoptosis as determined by propidium iodide staining. Further the percentage of LDH release was increased at increasing concentrations which is a measure of cell death. The levels of sialic acid levels and DNA, RNA and protein levels were decreased after treatment with methylene chloride extraction of Pestalotiopsis mangiferae. We suggests that methylene chloride extraction of Pestalotiopsis mangiferae might be considered for future therapeutic application with further studies against lung cancer. PMID:25206246

Greater taxol yield of fungus Pestalotiopsis hainanensis from dermatitic scurf of the giant panda (Ailuropoda melanoleuca).

PubMed

Gu, Yu; Wang, Yanlin; Ma, Xiaoping; Wang, Chengdong; Yue, Guizhou; Zhang, Yuetian; Zhang, Yunyan; Li, Shanshan; Ling, Shanshan; Liu, Xiaomin; Wen, Xintian; Cao, Sanjie; Huang, Xiaobo; Deng, Junliang; Zuo, Zhicai; Yu, Shumin; Shen, Liuhong; Wu, Rui

2015-01-01

While taxol yields of fungi from non-animal sources are still low, whether Pestalotiopsis hainanensis isolated from the scurf of a dermatitic giant panda, Ailuropoda melanoleuca, provides a greater taxol yield remains unknown. The objective of the study was to determine the corresponding taxol yield. The structure of the taxol produced by the fungus was evaluated by thin layer chromatography (TLC), ultraviolet (UV) spectroscopy, high-performance liquid chromatography (HPLC), (1)H and (13)C nuclear magnetic resonance spectroscopy ((1)H-NMR and (13)C-NMR), and time-of-flight mass spectrometry (TOF-MS), with standard taxol as a control. The results demonstrated that the P. hainanensis fungus produced taxol, which had the same structure as the standard taxol and yield of 1,466.87 μg/L. This fungal taxol yield from the dermatitic giant panda was significantly greater than those of fungus from non-animal sources. The taxol-producing fungus may be a potential candidate for the production of taxol on an industrial scale.

Inhibition of heme oxygenase-1 enhances the cytotoxic effect of gemcitabine in urothelial cancer cells.

PubMed

Miyake, Makito; Fujimoto, Kiyohide; Anai, Satoshi; Ohnishi, Sayuri; Nakai, Yasushi; Inoue, Takeshi; Matsumura, Yoshiaki; Tomioka, Atsushi; Ikeda, Tomohiro; Okajima, Eijiro; Tanaka, Nobumichi; Hirao, Yoshihiko

2010-06-01

Elevated heme oxygenase-1 (HO-1) is associated with resistance to chemo- and radiotherapy through anti-apoptotic function. The present study evaluated whether the HO-1 inhibitor, zinc protoporphyrin IX (ZnPP), enhances the cytotoxic effect of gemcitabine in urothelial carcinoma (UC). The in vitro cytotoxic effect of combination treatment of gemcitabine and ZnPP on UC cells was examined. The in vivo growth inhibitory effects of intraperitoneal administration of gemcitabine and/or ZnPP on mouse subcutaneous tumours were examined. The apoptotic changes were analysed with the detection of DNA fragmentation and cleaved caspase-3. HO-1 was up-regulated by both gemcitabine and irradiation treatment in vitro. ZnPP sensitised the UC cells to both therapies. Enhanced apoptosis was induced by the ZnPP combined with gemicitabine. ZnPP enhanced the antitumour effect of gemcitabine in vivo along with decreased numbers of proliferating cells and increased numbers of apoptotic cells. These findings suggest that ZnPP combined with gemcitabine or irradiation therapy may be an effective therapeutic modality for UC patients.

In vitro cell cultures obtained from different explants of Corylus avellana produce Taxol and taxanes

PubMed Central

Bestoso, Federica; Ottaggio, Laura; Armirotti, Andrea; Balbi, Alessandro; Damonte, Gianluca; Degan, Paolo; Mazzei, Mauro; Cavalli, Francesca; Ledda, Bernardetta; Miele, Mariangela

2006-01-01

Background Taxol is an effective antineoplastic agent, originally extracted from the bark of Taxus brevifolia with a low yield. Many attempts have been made to produce Taxol by chemical synthesis, semi-synthesis and plant tissue cultures. However, to date, the availability of this compound is not sufficient to satisfy the commercial requirements. The aim of the present work was to produce suspension cell cultures from plants not belonging to Taxus genus and to verify whether they produced Taxol and taxanes. For this purpose different explants of hazel (Corylus avellana species) were used to optimize the protocol for inducing in vitro callus, an undifferentiated tissue from which suspension cell cultures were established. Results Calli were successfully induced from stems, leaves and seeds grown in various hormone concentrations and combinations. The most suitable callus to establish suspension cell cultures was obtained from seeds. Media recovered from suspension cell cultures contained taxanes, and showed antiproliferative activity on human tumour cells. Taxol, 10-deacetyltaxol and 10-deacetylbaccatin III were the main taxanes identified. The level of Taxol recovered from the media of hazel cultures was similar to that found in yew cultures. Moreover, the production of taxanes in hazel cell cultures increased when elicitors were used. Conclusion Here we show that hazel cell cultures produce Taxol and taxanes under controlled conditions. This result suggests that hazel possesses the enzymes for Taxol production, which until now was considered to be a pathway particular to Taxus genus. The main benefit of producing taxanes through hazel cell cultures is that hazel is widely available, grows at a much faster rate in vivo, and is easier to cultivate in vitro than yew. In addition, the production of callus directly from hazel seeds shortens the culture time and minimizes the probability of contamination. Therefore, hazel could become a commercial source of Taxol and

Induction of oxidative stress by Taxol® vehicle Cremophor-EL triggers production of interleukin-8 by peripheral blood mononuclear cells through the mechanism not requiring de novo synthesis of mRNA.

PubMed

Ilinskaya, Anna N; Clogston, Jeffrey D; McNeil, Scott E; Dobrovolskaia, Marina A

2015-11-01

Understanding the ability of cytotoxic oncology drugs, and their carriers and formulation excipients, to induce pro-inflammatory responses is important for establishing safe and efficacious formulations. Literature data about cytokine response induction by the traditional formulation of paclitaxel, Taxol®, are controversial, and no data are available about the pro-inflammatory profile of the nano-albumin formulation of this drug, Abraxane®. Herein, we demonstrate and explain the difference in the cytokine induction profile between Taxol® and Abraxane®, and describe a novel mechanism of cytokine induction by a nanosized excipient, Cremophor EL, which is not unique to Taxol® and is commonly used in the pharmaceutical industry for delivery of a wide variety of small molecular drugs. Advances in nanotechnology have enabled the production of many nano-formulation drugs. The cellular response to drugs has been reported to be different between traditional and nano-formulations. In this article, the authors investigated and compared cytokine response induction profiles between Taxol® and Abraxane®. The findings here provided further understanding to create drugs with better safety profiles. Copyright © 2015 Elsevier Inc. All rights reserved.

Induction of taxol metabolism in the rat by dexamethasone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, C.D.; Gondi, K.N.; Walle, T.

1994-12-31

The antitumor drug taxol was metabolized to two major metabolites (RM1 and RM2) in adult male and female rat liver microsomes. The male rats produced RM1 2.6 fold faster than the females, and they produced RM2 3 fold faster than the females. This correlated well with the sex differences noticed in liver microsomal cytochrome P450 (CYP) 3A content (4.4 fold greater in male) and 6{beta}-hydroxylation of testosterone (2.4 fold greater in male). Taxol was metabolized to three major metabolites (RM1, RM2, and RM3) in adult male and female rat liver microsomes from rats pretreated with dexamethasone. Production of RM1 andmore » RM2 was increased in these rats (2.3 and 3.3 fold respectively in males; 6.5 and 8.7 fold respectively in females) as compared to the untreated rats. These results compared well with the induction of CYP 3A proteins (3.5 fold in male, 10 fold in female) and induction of 6{beta}-hydroxylation (1.9 fold in males, 3.8 fold in females). RM3, which was produced only by the rats pretreated with dexamethasone, had a retention time of 0.58 relative to taxol which corresponds to 6{alpha}- hydroxytaxol, the major human metabolite of taxol. This study indicates that taxol metabolism in the rat is likely due to CYP 3A enzymes. Although the evidence points toward CYP 3A1 as the major isoform involved, it does not rule out others. The findings also suggest that CYP 3A1 is responsible for the induced metabolite, RM3.« less

Lipid-laden macrophage infiltration of human adenocarcinoma in vivo associated with taxol and GCSF treatment.

PubMed

Abramson, N; Castro, S; Goldstein, J D

1997-01-01

This brief report illustrates the presence of lipid-laden macrophages in proximity to metastatic adenocarcinoma cells within the bone marrow of a patient receiving taxol and GCSF therapy. The pathophysiological mechanism is uncertain. Taxol, which is associated with macrophage function in vitro, may have been responsible for the recruitment of macrophages in this patient. GCSF could have contributed as well; however, GCSF usually has little effect on monocytes and macrophages.

Fluorescence imaging analysis of taxol-induced ASTC-a-1 cell death with cell swelling and cytoplasmic vacuolization

NASA Astrophysics Data System (ADS)

Chen, Tong-sheng; Sun, Lei; Wang, Longxiang; Wang, Huiying

2008-02-01

Taxol (Paclitaxel), an isolated component from the bark of the Pacific yew Taxus brevifolia, exhibits a broad spectrum of clinical activity against human cancers. Taxol can promote microtubule (MT) assembly, inhibit depolymerization, and change MT dynamics, resulting in disruption of the normal reorganization of the microtubule network required for mitosis and cell proliferation. However, the molecular mechanism of taxol-induced cell death is still unclear. In this report, CCK-8 was used to assay the inhibition of taxol on the human lung adenocarcinoma (ASTC-a-1) cells viability, confocal fluorescence microscope was used to monitor the morphology changes of cells with taxol treatment. We for the first time describe the characteristics of taxol-induced cells swelling, cytoplasmic vacuolization and cell death. Taxol induced swelling, cytoplasmatic vacuolization and cell death without cell shrinkage and membrane rupture. These features differ from those of apoptosis and resemble the paraptosis, a novel nonapoptotic PCD.

Interactions between Co-Habitating fungi Elicit Synthesis of Taxol from an Endophytic Fungus in Host Taxus Plants

PubMed Central

Soliman, Sameh S. M.; Raizada, Manish N.

2012-01-01

Within a plant, there can exist an ecosystem of pathogens and endophytes, the latter described as bacterial and fungal inhabitants that thrive without causing disease to the host. Interactions between microbial inhabitants represent a novel area of study for natural products research. Here we analyzed the interactions between the fungal endophytes of Taxus (yew) trees. Fungal endophytes of Taxus have been proposed to produce the terpenoid secondary metabolite, Taxol, an anti-cancer drug. It is widely reported that plant extracts stimulate endophytic fungal Taxol production, but the underlying mechanism is not understood. Here, Taxus bark extracts stimulated fungal Taxol production 30-fold compared to a 10-fold induction with wood extracts. However, candidate plant-derived defense compounds (i.e., salicylic acid, benzoic acid) were found to act only as modest elicitors of fungal Taxol production from the endophytic fungus Paraconiothyrium SSM001, consistent with previous studies. We hypothesized the Taxus plant extracts may contain elicitors derived from other microbes inhabiting these tissues. We investigated the effects of co-culturing SSM001 with other fungi observed to inhabit Taxus bark, but not wood. Surprisingly, co-culture of SSM001 with a bark fungus (Alternaria) caused a ∼threefold increase in Taxol production. When SSM001 was pyramided with both the Alternaria endophyte along with another fungus (Phomopsis) observed to inhabit Taxus, there was an ∼eightfold increase in fungal Taxol production from SSM001. These results suggest that resident fungi within a host plant interact with one another to stimulate Taxol biosynthesis, either directly or through their metabolites. More generally, our results suggest that endophyte secondary metabolism should be studied in the context of its native ecosystem. PMID:23346084

The influence of the combined treatment with Vadimezan (ASA404) and taxol on the growth of U251 glioblastoma xenografts

PubMed Central

2012-01-01

Background One of the most important biological characteristics of Glioblastoma multiforme (GBM) is high vascular density. Vadimezan (ASA404, DMXAA) belongs to the class of small molecule vascular disrupting agents (VDA) that cause disruption of established tumor vessels and subsequent tumor hemorrhagic necrosis. Its selective antivascular effect is mediated by intratumoral induction of several cytokines including tumor necrosis factor-α (TNF-α), granulocyte-colony-stimulating factor (G-CSF), interleukin 6 (IL-6) and macrophage inflammatory protein 1α (MIP-1α). Preclinical studies have demonstrated that ASA404 acts synergistically with taxanes. In this study, we investigated if treatment of mice bearing U251 human glioblastoma xenografts with ASA404 and taxol may be synergistic. Therapy response was evaluated by measuring changes in tumor size and metabolic activity using 18F-FDG PET (Fluorodeoxyglucose - positron emision tomography) imaging. Methods U251 cells were inoculated s.c. in the right hind limb of NMRI-Foxn1nu athymic female nude mice. Animals were randomly assigned into 4 groups (7–9 animals/group) for treatment: control, taxol, ASA404, and ASA404 plus taxol. The animals received either a single dose of taxol (10 mg/kg), ASA404 (27.5 mg/kg), or taxol (10 mg/kg) plus ASA404 (27.5 mg/kg) administered i.p.; ASA404 was administred 24 h after the treatment with taxol. 4 and 24 h after treatment with ASA404 (28 and 48 h hours after treatment with taxol) 18 F-FDG PET scans were performed. Results The treatment with taxol did not affect the tumor growth in comparison to untreated controls. The treatment of animals with single dose ASA404 alone or in combination with taxol caused a significant delay in tumor growth. The combined treatment did not decrease the growth of the xenografts significantly more than ASA404 alone, but early changes in tumor 18 F-FDG uptake preceded subsequent growth inhibition. The tumor weights, which were

Uremic toxins enhance statin-induced cytotoxicity in differentiated human rhabdomyosarcoma cells.

PubMed

Uchiyama, Hitoshi; Tsujimoto, Masayuki; Shinmoto, Tadakazu; Ogino, Hitomi; Oda, Tomoko; Yoshida, Takuya; Furukubo, Taku; Izumi, Satoshi; Yamakawa, Tomoyuki; Tachiki, Hidehisa; Minegaki, Tetsuya; Nishiguchi, Kohshi

2014-09-03

The risk of myopathy and rhabdomyolysis is considerably increased in statin users with end-stage renal failure (ESRF). Uremic toxins, which accumulate in patients with ESRF, exert cytotoxic effects that are mediated by various mechanisms. Therefore, accumulation of uremic toxins might increase statin-induced cytotoxicity. The purpose of this study was to determine the effect of four uremic toxins-hippuric acid, 3-carboxy-4-methyl-5-propyl-2-furanpropionate, indole-3-acetic acid, and 3-indoxyl sulfate-on statin-induced myopathy. Differentiated rhabdomyosarcoma cells were pre-treated with the uremic toxins for seven days, and then the cells were treated with pravastatin or simvastatin. Cell viability and apoptosis were assessed by viability assays and flow cytometry. Pre-treatment with uremic toxins increased statin- but not cisplatin-induced cytotoxicity (p < 0.05 vs. untreated). In addition, the pre-treatment increased statin-induced apoptosis, which is one of the cytotoxic factors (p < 0.05 vs. untreated). However, mevalonate, farnesol, and geranylgeraniol reversed the effects of uremic toxins and lowered statin-induced cytotoxicity (p < 0.05 vs. untreated). These results demonstrate that uremic toxins enhance statin-induced apoptosis and cytotoxicity. The mechanism underlying this effect might be associated with small G-protein geranylgeranylation. In conclusion, the increased severity of statin-induced rhabdomyolysis in patients with ESRF is likely due to the accumulation of uremic toxins.

Isolation of anticancer drug TAXOL from Pestalotiopsis breviseta with apoptosis and B-Cell lymphoma protein docking studies.

PubMed

Kathiravan, G; Sureban, Sripathi M; Sree, Harsha N; Bhuvaneshwari, V; Kramony, Evelin

2012-12-01

Extraction and investigation of TAXOL from Pestalotiopsis breviseta (Sacc.) using protein docking, which is a computational technique that samples conformations of small molecules in protein-binding sites. Scoring functions are used to assess which of these conformations best complements the protein binding site and active site prediction. Coelomycetous fungi P. breviseta (Sacc.) Steyaert was screened for the production of TAXOL, an anticancer drug. TAXOL PRODUCTION WAS CONFIRMED BY THE FOLLOWING METHODS: Ultraviolet (UV) spectroscopic analysis, Infrared analysis, High performance liquid chromatography analysis (HPLC), and Liquid chromatography mass spectrum (LC-MASS). TAXOL produced by the fungi was compared with authentic TAXOL, and protein docking studies were performed. The BCL2 protein of human origin showed a higher affinity toward the compound paclitaxel. It has the binding energy value of -13.0061 (KJ/Mol) with four hydrogen bonds.

[Apoptosis mechanism of taxol combined with resveratrol on human laryngeal carcinoma Hep-2 cells].

PubMed

Lu, Chen-Xin; Sun, Jing-Hui; Wu, Chun-Lian

2016-02-01

Laryngeal cancer is one of the most common malignant tumors in the respiratory tumors, and its incidence ranks second highest in the respiratory tumors. Resveratrol (Res) is a kind of polyphenols, which can inhibit nucleotides can inhibit the growth of liver cancer cells, gastric cancer cells, pancreatic cells and other tumor cells by inhibiting ribonucleotide reductase in the cells. Taxol (Tax) is a kind of secondary metabolites of Taxus chinensis, which has anti-tumor activity for breast cancer, cervical cancer, ovarian cancer and other tumors by inhibiting cellular microtubule depolymerization. But at present the effects of resveratrol combined with taxol on human laryngeal carcinoma cell strain Hep-2 and their underlying molecular mechanisms are rarely reported. After human laryngeal cancer cell Hep-2 cells were processed with resveratrol (Res) and taxol (Tax), CCK-8 assay was used to evaluate the effect of these two herbs on the proliferation of cancer cells; AO/PI staining and JC-1 were used to detect Hep-1 cells apoptosis; the expression of Bax, Bcl-2, PARP, TRIB3, and XIAP genes was detected by real time quantitative PCR; the activity of caspase-3 and caspase-8 was determined with quantitative fluorescence method. The experimental results showed that compared with Tax, Res medication alone, joint group significantly enhanced inhibition of Hep-2 cells activity, decreased the dosage of Tax, increased the expression of Bax and PARP, TRIB3, reduced the expression of the Bcl-2 and XIAP, and promoted the activity of caspase-3 and caspase-8. The test results showed that compared with the single medication, combined group could significantly increase the inhibitory effect on Hep-2 cells, significantly reduce Tax dosage, increase expressions of Bax, PARP, TRIB3, reduce expressions of Bcl-2, XIAP, and promote activity of caspase-3, caspase-8. This indicated apoptosis of human laryngeal carcinoma cell strain Hep-2 may be induced with Res, Tax, and the combination of

Synthetic miR-145 Mimic Enhances the Cytotoxic Effect of the Antiangiogenic Drug Sunitinib in Glioblastoma.

PubMed

Liu, Hongwei; Liu, Zhixiong; Jiang, Bing; Huo, Lei; Liu, Jinfang; Lu, Jingchen

2015-06-01

Although aggressive therapeutic regimen has been applied in the treatment of Glioblastoma (GBM), the prognosis of patients with GBM remains poor. Preclinical studies have demonstrated the efficacy of Suntinib in GBM both in vitro and in vivo. In this study, we showed that the cytotoxicity was enhanced by transfection with miR-145 mimic. In addition, we suggested that the enhanced cytotoxicity of Sunitinib by miR-145 mimic was mediated by inhibition of both P-gp and Bcrp.

Ionic-Liquid-Based Paclitaxel Preparation: A New Potential Formulation for Cancer Treatment.

PubMed

Chowdhury, Md Raihan; Moshikur, Rahman Md; Wakabayashi, Rie; Tahara, Yoshiro; Kamiya, Noriho; Moniruzzaman, Muhammad; Goto, Masahiro

2018-06-04

Paclitaxel (PTX) injection (i.e., Taxol) has been used as an effective chemotherapeutic treatment for various cancers. However, the current Taxol formulation contains Cremophor EL, which causes hypersensitivity reactions during intravenous administration and precipitation by aqueous dilution. This communication reports the preliminary results on the ionic liquid (IL)-based PTX formulations developed to address the aforementioned issues. The formulations were composed of PTX/cholinium amino acid ILs/ethanol/Tween-80/water. A significant enhancement in the solubility of PTX was observed with considerable correlation with the density and viscosity of the ILs, and with the side chain of the amino acids used as anions in the ILs. Moreover, the formulations were stable for up to 3 months. The driving force for the stability of the formulation was hypothesized to be the involvement of different types of interactions between the IL and PTX. In vitro cytotoxicity and antitumor activity of the IL-based formulations were evaluated on HeLa cells. The IL vehicles without PTX were found to be less cytotoxic than Taxol, while both the IL-based PTX formulation and Taxol exhibited similar antitumor activity. Finally, in vitro hypersensitivity reactions were evaluated on THP-1 cells and found to be significantly lower with the IL-based formulation than Taxol. This study demonstrated that specially designed ILs could provide a potentially safer alternative to Cremophor EL as an effective PTX formulation for cancer treatment giving fewer hypersensitivity reactions.

Androgen and taxol cause cell type-specific alterations of centrosome and DNA organization in androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cells

NASA Technical Reports Server (NTRS)

Schatten, H.; Ripple, M.; Balczon, R.; Weindruch, R.; Chakrabarti, A.; Taylor, M.; Hueser, C. N.

2000-01-01

We investigated the effects of androgen and taxol on the androgen-responsive LNCaP and androgen-independent DU145 prostate cancer cell lines. Cells were treated for 48 and 72 h with 0.05-1 nM of the synthetic androgen R1881 and with 100 nM taxol. Treatment of LNCaP cells with 0.05 nM R1881 led to increased cell proliferation, whereas treatment with 1 nM R1881 resulted in inhibited cell division, DNA cycle arrest, and altered centrosome organization. After treatment with 1 nM R1881, chromatin became clustered, nuclear envelopes convoluted, and mitochondria accumulated around the nucleus. Immunofluorescence microscopy with antibodies to centrosomes showed altered centrosome structure. Although centrosomes were closely associated with the nucleus in untreated cells, they dispersed into the cytoplasm after treatment with 1 nM R1881. Microtubules were only faintly detected in 1 nM R1881-treated LNCaP cells. The effects of taxol included microtubule bundling and altered mitochondria morphology, but not DNA organization. As expected, the androgen-independent prostate cancer cell line DU145 was not affected by R1881. Treatment with taxol resulted in bundling of microtubules in both cell lines. Additional taxol effects were seen in DU145 cells with micronucleation of DNA, an indication of apoptosis. Simultaneous treatment with R1881 and taxol had no additional effects on LNCaP or DU145 cells. These results suggest that LNCaP and DU145 prostate cancer cells show differences not only in androgen responsiveness but in sensitivity to taxol as well. Copyright 2000 Wiley-Liss, Inc.

Isolation of anticancer drug TAXOL from Pestalotiopsis breviseta with apoptosis and B-Cell lymphoma protein docking studies

PubMed Central

Kathiravan, G.; Sureban, Sripathi M.; Sree, Harsha N.; Bhuvaneshwari, V.; Kramony, Evelin

2012-01-01

Background: Extraction and investigation of TAXOL from Pestalotiopsis breviseta (Sacc.) using protein docking, which is a computational technique that samples conformations of small molecules in protein-binding sites. Scoring functions are used to assess which of these conformations best complements the protein binding site and active site prediction. Materials and Methods: Coelomycetous fungi P. breviseta (Sacc.) Steyaert was screened for the production of TAXOL, an anticancer drug. Results: TAXOL production was confirmed by the following methods: Ultraviolet (UV) spectroscopic analysis, Infrared analysis, High performance liquid chromatography analysis (HPLC), and Liquid chromatography mass spectrum (LC-MASS). TAXOL produced by the fungi was compared with authentic TAXOL, and protein docking studies were performed. Conclusion: The BCL2 protein of human origin showed a higher affinity toward the compound paclitaxel. It has the binding energy value of −13.0061 (KJ/Mol) with four hydrogen bonds. PMID:24808664

The flavonoid quercetin transiently inhibits the activity of taxol and nocodazole through interference with the cell cycle

PubMed Central

Samuel, Temesgen; Fadlalla, Khalda; Turner, Timothy; Yehualaeshet, Teshome E.

2010-01-01

Quercetin is a flavonoid with anticancer properties. In this study, we examined the effects of quercetin on cell cycle, viability and proliferation of cancer cells, either singly or in combination with the microtubule-targeting drugs taxol and nocodazole. Although quercetin induced cell death in a dose dependent manner, 12.5-50μM quercetin inhibited the activity of both taxol and nocodazole to induce G2/M arrest in various cell lines. Quercetin also partially restored drug-induced loss in viability of treated cells for up to 72 hours. This antagonism of microtubule-targeting drugs was accompanied by a delay in cell cycle progression and inhibition of the buildup of cyclin-B1 at the microtubule organizing center of treated cells. However, quercetin did not inhibit the microtubule targeting of taxol or nocodazole. Despite the short-term protection of cells by quercetin, colony formation and clonogenicity of HCT116 cells were still suppressed by quercetin or quercetin-taxol combination. The status of cell adherence to growth matrix was critical in determining the sensitivity of HCT116 cells to quercetin. We conclude that while long-term exposure of cancer cells to quercetin may prevent cell proliferation and survival, the interference of quercetin with cell cycle progression diminishes the efficacy of microtubule-targeting drugs to arrest cells at G2/M. PMID:21058190

IFNγ enhances cytotoxic efficiency of the cytotoxic T lymphocytes against human glioma cells.

PubMed

Shao, Shengwen; Risch, Eric; Burner, Danielle; Lu, Lingeng; Minev, Boris; Ma, Wenxue

2017-06-01

Cytotoxic T lymphocytes (CTLs) are a key player in cancer immunotherapies, and MHC class I molecules on the cell surface are crucial for cellular recognition. However, the aberrant expression of MHC class I molecules is frequently found in various malignancies. IFNγ has dual functions in cancer progression, and its effect on tumor immunity is controversial. To investigate whether IFNγ can enhance cytotoxic efficiency of the tumor antigen-specific CTLs, we generated the CTLs using modified human dendritic cells as antigen presenting cells, then studied the activities of CTLs on human leukocyte antigen (HLA)-A2 positive glioma cells treated with, or without IFNγ. The results from both ELISpot and cytotoxicity assays demonstrated that the CTLs recognized and eliminated the HLA-A2 positive glioma cells treated with IFNγ more effectively when compared to the glioma cells deprived of IFNγ treatment. In addition, in vitro experiments showed that the levels of MHC class I molecules were upregulated in all of the HLA-A2 positive glioma cells. Using the publicly accessed TCGA data of low-grade glioma, we found significantly positive associations between IFNγ and both MHC class I molecules and CD8 + T cell activation score (p<0.0001). Furthermore, we found a significantly reduced risk of death in the glioma patients with high T cell activation score in comparison to those with low score (p=0.022). These findings suggest that a clinical application of IFNγ treatment may have potential benefits. Copyright © 2017. Published by Elsevier B.V.

Suppression of miR-19b enhanced the cytotoxic effects of mTOR inhibitors in human neuroblastoma cells.

PubMed

Chen, Yun; Tsai, Ya-Hui; Tseng, Bor-Jiun; Pan, Hsin-Yen; Tseng, Sheng-Hong

2016-11-01

Mammalian target of rapamycin (mTOR) inhibitors exert significant antitumor effects on several cancer cell types. In this study, we investigated the effects of mTOR inhibitors, in particular the regulation of the microRNA, in neuroblastoma cells. AZD8055 (a new mTOR inhibitor)- or rapamycin-induced cytotoxic effects on neuroblastoma cells were studied. Western blotting was used to investigate the expression of various proteins in the mTOR pathway. MicroRNA precursors and antagomirs were transfected into cells to manipulate the expression of target microRNA. AZD8055 exerted stronger cytotoxic effects than rapamycin in neuroblastoma cells (p<0.03). In addition, AZD8055 suppressed the mTOR pathway and increased the expression of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in the neuroblastoma cells. AZD8055 significantly decreased miR-19b expression (p<0.005); in contrast, rapamycin increased miR-19b expression (p<0.05). Transfection of miR-19b antagomir into the neuroblastoma cells mimicked the effects of AZD8055 treatment, whereas miR-19b overexpression reversed the effects of AZD8055. Combination of miR-19b knockdown and rapamycin treatment significantly improved the sensitivity of neuroblastoma cells to rapamycin (p<0.02). Suppression of miR-19b may enhance the cytotoxic effects of mTOR inhibitors in neuroblastoma cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Enhanced cytotoxicity of anticancer drug delivered by novel nanoscale polymeric carrier

NASA Astrophysics Data System (ADS)

Stoika, R.; Boiko, N.; Senkiv, Y.; Shlyakhtina, Y.; Panchuk, R.; Finiuk, N.; Filyak, Y.; Bilyy, R.; Kit, Y.; Skorohyd, N.; Klyuchivska, O.; Zaichenko, A.; Mitina, N.; Ryabceva, A.

2013-04-01

We compared in vitro action of highly toxic anticancer drug doxorubicin under its delivery to the mammalian tumor cells in free form and after encapsulation in novel bio-functionalized nanoscale polymeric carrier. Such encapsulation was found to enhance significantly drug uptake by the targeted cells, as well as its cytotoxic action. 10 times higher cytotoxicity of the carrier-immobilized doxorubicin comparing to its free form was demonstrated by direct cell counting, and 5 times higher cytotoxicity of encapsulated doxorubicin was shown by FACS analysis. The polymeric carrier itself did not possess significant toxicity in vitro or in vivo (laboratory mice). The carrier protected against negative side effects of doxorubicin in mice with experimental NK/Ly lymphoma. The life duration of tumor-bearing animals treated with doxorubicin-carrier complex was significantly longer than life duration in animals treated with free doxorubicin. Besides, the effective treatment dose of the carrier-delivered doxorubicin in tumor-bearing mice was 10 times lower than such dose of free doxorubicin. Thus, novel nanoscale polymers possess high potential as drug carrier.

Association between Twist and multidrug resistance gene-associated proteins in Taxol®-resistant MCF-7 cells and a 293 cell model of Twist overexpression.

PubMed

Wang, Li; Tan, Rui-Zhi; Zhang, Zhi-Xia; Yin, Rui; Zhang, Yong-Liang; Cui, Wei-Jia; He, Tao

2018-01-01

Multidrug resistance (MDR) severely limits the effectiveness of chemotherapy. Previous studies have identified Twist as a key factor of acquired MDR in breast, gastric and prostate cancer. However, the underlying mechanisms of action of Twist in MDR remain unclear. In the present study, the expression levels of MDR-associated proteins, including lung resistance-related protein (LRP), topoisomerase IIα (TOPO IIα), MDR-associated protein (MRP) and P-glycoprotein (P-gp), and the expression of Twist in cancerous tissues and pericancerous tissues of human breast cancer, were examined. In order to simulate Taxol ® resistance in cells, a Taxol ® -resistant human mammary adenocarcinoma cell subline (MCF-7/Taxol ® ) was established by repeatedly exposing MCF-7 cells to high concentrations of Taxol ® (up to 15 µg/ml). Twist was also overexpressed in 293 cells by transfecting this cell line with pcDNA5/FRT/TO vector containing full-length hTwist cDNA to explore the dynamic association between Twist and MDR gene-associated proteins. It was identified that the expression levels of Twist, TOPO IIα, MRP and P-gp were upregulated and LRP was downregulated in human breast cancer tissues, which was consistent with the expression of these proteins in the Taxol ® -resistant MCF-7 cell model. Notably, the overexpression of Twist in 293 cells increased the resistance to Taxol ® , Trichostatin A and 5-fluorouracil, and also upregulated the expression of MRP and P-gp. Taken together, these data demonstrated that Twist may promote drug resistance in cells and cancer tissues through regulating the expression of MDR gene-associated proteins, which may assist in understanding the mechanisms of action of Twist in drug resistance.

The combination of dimethoxycurcumin with DNA methylation inhibitor enhances gene re-expression of promoter-methylated genes and antagonizes their cytotoxic effect

PubMed Central

Hassan, Hazem E.; Keita, Jean-Arnaud; Narayan, Lawrence; Brady, Sean M.; Frederick, Richard; Carlson, Samuel; C. Glass, Karen; Natesan, Senthil; Buttolph, Thomm; Fandy, Tamer E.

2016-01-01

ABSTRACT Curcumin and its analogs exhibited antileukemic activity either as single agent or in combination therapy. Dimethoxycurcumin (DMC) is a more metabolically stable curcumin analog that was shown to induce the expression of promoter-methylated genes without reversing DNA methylation. Accordingly, co-treatment with DMC and DNA methyltransferase (DNMT) inhibitors could hypothetically enhance the re-expression of promoter-methylated tumor suppressor genes. In this study, we investigated the cytotoxic effects and epigenetic changes associated with the combination of DMC and the DNMT inhibitor decitabine (DAC) in primary leukemia samples and cell lines. The combination demonstrated antagonistic cytotoxic effects and was minimally cytotoxic to primary leukemia cells. The combination did not affect the metabolic stability of DMC. Although the combination enhanced the downregulation of nuclear DNMT proteins, the hypomethylating activity of the combination was not increased significantly compared to DAC alone. On the other hand, the combination significantly increased H3K27 acetylation (H3K27Ac) compared to the single agents near the promoter region of promoter-methylated genes. Furthermore, sequential chromatin immunoprecipitation (ChIP) and DNA pyrosequencing of the chromatin-enriched H3K27Ac did not show any significant decrease in DNA methylation compared to other regions. Consequently, the enhanced induction of promoter-methylated genes by the combination compared to DAC alone is mediated by a mechanism that involves increased histone acetylation and not through potentiation of the DNA hypomethylating activity of DAC. Collectively, our results provide the mechanistic basis for further characterization of this combination in leukemia animal models and early phase clinical trials. PMID:27588609

KHYG-1, a model for the study of enhanced natural killer cell cytotoxicity.

PubMed

Suck, Garnet; Branch, Donald R; Smyth, Mark J; Miller, Richard G; Vergidis, Joanna; Fahim, Soad; Keating, Armand

2005-10-01

To compare the cytotoxicity of KHYG-1 with other natural killer (NK)/NK T-cell lines and identify molecules that may be associated with enhanced cytotoxicity, thereby eventually leading to improved NK cell-mediated cancer immunotherapy. NK/NK T-cell lines KHYG-1, NK-92, YT, and SNT-8 were compared with a novel flow cytometric cytotoxicity assay under different culture conditions. Transcription, expression, and phosphorylation studies were performed using polymerase chain reaction sequence-specific primers, reverse transcription polymerase chain reaction, immunoblotting, and flow cytometry. KHYG-1 is a highly cytotoxic cell line, exceeding the cytolytic capacity of the other cell lines against K562. KHYG-1 is also highly cytotoxic against the leukemia cell lines EM2, EM3, and HL60. The novel activation receptor NKp44 and its adaptor, DAP12, NKG2D, and constitutively phosphorylated ERK2 may be associated with the enhanced cytotoxicity of KHYG-1. This cell line most likely mediates cytolysis by granzyme M (but not granzymes A and B) together with perforin, which is constitutively fully cleaved to the 60-kD form, in contrast to the other cell lines. KHYG-1 is a valuable model for the study of enhanced cytotoxicity by NK cells. In addition to the activation of NKp44, KHYG-1 may induce apoptosis of tumor cells by the newly described granzyme M/perforin pathway. Targeted modifications of effector molecules demonstrated in this model could generate NK cells with even greater killing ability that may be particularly attractive for clinical application. Moreover, our demonstration of greater cytotoxicity of KHYG-1 versus NK-92 cells, already in clinical trials, suggests a direct therapeutic role for KHYG-1.

Enhanced cytotoxic effect of cisplatin using diagnostic ultrasound and microbubbles in vitro

NASA Astrophysics Data System (ADS)

Sasaki, Noboru; Nakamura, Kensuke; Murakami, Masahiro; Lim, Sue Yee; Ohta, Hiroshi; Yamasaki, Masahiro; Takiguchi, Mitsuyoshi

2012-10-01

Diagnostic ultrasound has accomplished drug and gene delivery by ultrasound targeted microbubble destruction (UTMD). However, the efficacy of delivery is still relatively low. Therefore, we optimized conditions of UTMD using diagnostic ultrasound and ultrasound contrast agent microbubbles. Canine thyroid adenocarcinoma cells were cultured in a 96-well plate. After addition of cisplatin and Sonazoid®, the plate was inverted to raise microbubbles near cells and incubated. Cells were exposed to diagnostic ultrasound using a linear probe operated in the contrast harmonic imaging mode. The center frequency was 2.5 MHz with a mechanical index of 1.33 and a frame rate of 48 frames/sec. Cytotoxic effect of cisplatin was evaluated 24h after exposure using trypan blue dye exclusion test. We optimized incubation duration, cisplatin concentration, and the relationship between microbubble concentration and exposure duration. The optimum enhancement was observed at incubation duration of 5min, cisplatin concentration of 1 μg/ml, and microbubble concentration of 2.4 × 105 microbubbles/ml. Exposure duration did not influence the enhancement at the microbubble concentration of 2.4 × 105 microbubbles/ml. Our results suggest that relative low concentrations of drug and microbubbles with short exposure duration might be sufficient for drug delivery by UTMD using diagnostic ultrasound.

Redistribution of fluorescently labeled tubulin in the mitotic apparatus of sand dollar eggs and the effects of taxol.

PubMed

Hamaguchi, Y; Toriyama, M; Sakai, H; Hiramoto, Y

1987-02-01

Fluorescently labeled tubulin was quickly incorporated into the mitotic apparatus when injected into a live sand dollar egg. After a rectangular area (1.6 X 16 microns) of the mitotic spindle was photobleached at metaphase or anaphase by the irradiation of a laser microbeam, redistribution of fluorescence was almost complete within 30 sec. The photobleached area did not change in shape during the redistribution. During the period of redistribution, the bleached area moved slightly toward the near pole at metaphase and anaphase (means: 1.6 and 1.8 micron/min, respectively). These results indicate that redistribution was not due to the exchange of tubulin subunits only at the ends of microtubules but to their rapid exchange at sites along the microtubules in the bleached region. Furthermore, treadmilling of tubulin molecules along with the spindle microtubules possibly occurred at the rate of 1.6 micron/min at metaphase. Birefringence of the mitotic apparatus increased with a large increase in both the number and length of astral rays shortly after taxol was injected. However, the microtubules did not all seem to elongate at the same rate but appeared to become equalized in length. Chromosome movement stopped within 60 sec after the injection. Centrospheres became large and the labeled tubulin already incorporated into the centrospheres was excluded from the enlarged centrospheres. Shortly after the labeled tubulin was injected following the injection of taxol, it accumulated in the peripheral region of the centrospheres, suggesting that microtubules first assembled at this region. Fluorescently labeled tubulin in the mitotic apparatus in the egg after injection of taxol was redistributed much more slowly after photobleaching than in uninjected eggs.

Bioreactor engineering as an enabling technology to tap biodiversity. The case of taxol.

PubMed

Shuler, M L

1994-11-30

One barrier to exploiting the chemical and genetic diversity in nature is the difficulty of cultivating many organisms in a controlled manner. In some cases it is difficult to achieve growth. In many others, good growth is achieved, but the expression of the organism's genetic potential to make a desired product is not realized. The thesis of this paper is that a coupling of an understanding of reactor engineering principles with the basic knowledge of the biology is often necessary to circumvent these barriers. In many cases the construction of appropriate cultivation systems is a necessary step to better understanding of cellular physiology. In some cases the chemical of interest is of high social utility and comes from a natural source that is uncommon and difficult to secure. In these cases a method of controlled cultivation becomes a prerequisite for commercial exploitation. These points were illustrated using a taxol. Taxol is an important new anticancer drug whose development has been greatly impeded by supply problems. Taxol has been derived from the park of the pacific yew tree, a process that kills the tree. The pacific yew is a relatively uncommon tree and very slow growing. One alternative to the natural source is plant cell culture. Such cultures can produce significant levels of taxol with substantial release into the medium. Taxane products not observed in typical extracts from field-grown plants can be found in cell cultures, indicating the potential unmasking of pathways. These cultures are quite responsive to changes in their environments as illustrated by the summary of initial observations. With regard to natural compounds, biochemical engineers can play a major role in the capture and preservation of producing systems, in the discovery of useful compounds, and in providing the basis for commercial production of natural compounds.

Proanthocyanidins from Uncaria rhynchophylla induced apoptosis in MDA-MB-231 breast cancer cells while enhancing cytotoxic effects of 5-fluorouracil.

PubMed

Chen, Xiao-Xin; Leung, George Pak-Heng; Zhang, Zhang-Jin; Xiao, Jian-Bo; Lao, Li-Xing; Feng, Feng; Mak, Judith Choi-Wo; Wang, Ying; Sze, Stephen Cho-Wing; Zhang, Kalin Yan-Bo

2017-09-01

Breast cancer is the most frequently diagnosed cancer and cause of cancer death in women worldwide. Current treatments often result in systematic toxicity and drug resistance. Combinational use of non-toxic phytochemicals with chemotherapeutic agents to enhance the efficacy and reduce toxicity would be one promising approach. In this study, bioactive proanthocyanidins from Uncaria rhynchophylla (UPAs) were isolated and their anti-breast cancer effects alone and in combination with 5- fluorouracil (5-FU) were investigated in MDA-MB-231 breast cancer cells. The results showed that UPAs significantly inhibited cell viability and migration ability in a dose-dependent manner. Moreover, UPAs induced apoptosis in a dose-dependent manner which was associated with increased cellular reactive oxygen species production, loss of mitochondrial membrane potential, increases of Bax/Bcl-2 ratio and levels of cleaved caspase 3. Treatments of the cells with UPAs resulted in an increase in G2/M cell cycle arrest. Cytotoxic effects of 5-FU against MDA-MB-231 cells were enhanced by UPAs. The combination treatment of UPAs and 5-FU for 48 h elicited a synergistic cytotoxic effect on MDA-MB-231 cells. Altogether, these data suggest that UPAs are potential therapeutic agents for breast cancer. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cytotoxic and anti-angiogenic paclitaxel solubilized and permeation-enhanced by natural product nanoparticles

PubMed Central

Liu, Zhijun; Zhang, Fang; Koh, Gar Yee; Dong, Xin; Hollingsworth, Javoris; Zhang, Jian; Russo, Paul S.; Yang, Peiying; Stout, Rhett W.

2014-01-01

Paclitaxel (PTX) is one of the most potent intravenous chemotherapeutic agents to date, yet an oral formulation has been problematic due to its low solubility and permeability. Using the recently discovered solubilizing properties of rubusoside (RUB), we investigated this unique PTX-RUB formulation. Paclitaxel was solubilized by RUB in water to levels of 1.6 to 6.3 mg/mL at 10 to 40% weight/volume. These, nanomicellar, PTX-RUB complexes were dried to a powder which was subsequently reconstituted in physiologic solutions. After 2.5 hrs in gastric fluid 85 to 99% of PTX-RUB remained soluble, while 79 to 96% remained soluble in intestinal fluid. The solubilization of PTX was mechanized by the formation of water-soluble spherical nanomicelles between PTX and RUB with an average diameter of 6.6 nm. Compared with Taxol®, PTX-RUB nanoparticles were nearly four times more permeable in Caco-2 cell monocultures. In a side-by-side comparison with DMSO-solubilized PTX, PTX-RUB maintained the same level of cytotoxicity against three human cancer cell lines with IC50 values ranging from 4 nM to 20 nM. Additionally, tubular formation and migration of HUVECs were inhibited at levels as low as 5 nM. These chemical and biological properties demonstrated by the PTX-RUB nanoparticles may improve oral bioavailability and enable further pharmacokinetic, toxicologic, and efficacy investigations. PMID:25243454

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

PubMed

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

2016-09-09

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.

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

Platinum anticancer agents and antidepressants: desipramine enhances platinum-based cytotoxicity in human colon cancer cells

PubMed Central

Kabolizadeh, Peyman; Engelmann, Brigitte J.; Pullen, Nicholas; Stewart, Jennifer K.; Ryan, John J.

2011-01-01

A unique synergistic effect on platinum drug cytotoxicity is noted in the presence of the tricyclic anti-depressant desipramine. Desipramine is used for treating neuropathic pain, particularly in prostate cancer patients. The clinically used drugs cisplatin (cis-[PtCl2(NH3)2]), oxaliplatin [1,2-diaminocyclohexaneoxalatoplatinum(II)], and the cationic trinuclear agent BBR3464 [{trans-PtCl(NH3)2}2-μ-(trans-Pt(NH3)2(H2N(CH2)6NH2)2)]4+, which has undergone evaluation in phase II clinical trials for activity in lung and ovarian cancers, were evaluated. Surprisingly, desipramine greatly augments the cytotoxicity of all the platinum-based chemotherapeutics in HCT116 colorectal carcinoma cell lines. Desipramine enhanced cellular accumulation of cisplatin, but had no effect on the accumulation of oxaliplatin or BBR3464, suggesting that enhanced accumulation could not be a consistent means by which desipramine altered the platinum-drug-mediated cytotoxicity. The desipramine/cisplatin combination resulted in increased levels of p53 as well as mitochondrial damage, caspase activation, and poly(ADP ribose) polymerase cleavage, suggesting that desipramine may synergize with cisplatin more than with other platinum chemotherapeutics partly by activating distinct apoptotic pathways. The study argues that desipramine may be a means of enhancing chemoresponsiveness of platinum drugs and the results warrant further investigation. The results emphasize the importance of understanding the differential pharmacological action of adjuvants employed in combinations with cancer chemotherapeutics. PMID:21918844

Modulation of cytotoxic T lymphocyte, natural killer cell, antibody-dependent cellular cytotoxicity, and antibody-dependent complement-mediated cytotoxicity by Vernonia cinerea L. and vernolide-A in BALB/c mice via enhanced production of cytokines IL-2 and IFN-γ.

PubMed

Pratheeshkumar, Poyil; Kuttan, Girija

2012-02-01

Effect of Vernonia cinerea L. and vernolide-A on cell-mediated immune (CMI) response was studied in normal as well as tumor-bearing BALB/c mice. Administration of V. cinerea and vernolide-A significantly enhanced natural killer (NK) cell activity in both normal as well as tumor-bearing animals, and the activity was observed earlier than in tumor-bearing control animals. Antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent complement-mediated cytotoxicity (ACC) were also enhanced significantly in both normal as well as tumor-bearing animals after V. cinerea and vernolide-A administration compared with untreated control tumor-bearing animals. Extract and vernolide-A showed a significant increase in cytotoxic T lymphocyte (CTL) production in both the in vivo and in vitro models. The level of cytokines such as interleukin (IL)-2 and interferon (IFN)-γ were also enhanced by the treatment of V. cinerea and vernolide-A in both normal as well as tumor-bearing animals. This study demonstrated that V. cinerea extract and vernolide-A stimulate the CTL, NK cell, ADCC, and ADCC through enhanced secretion of IL-2 and IFN-γ.

Zinc enhances temozolomide cytotoxicity in glioblastoma multiforme model systems

PubMed Central

Toren, Amos; Pismenyuk, Tatyana; Yalon, Michal; Freedman, Shani; Simon, Amos J.; Fisher, Tamar; Moshe, Itai; Reichardt, Juergen K.V.; Constantini, Shlomi; Mardor, Yael; Last, David; Guez, David; Daniels, Dianne; Assoulin, Moria; Mehrian-Shai, Ruty

2016-01-01

Temozolomide (TMZ) is an alkylating agent that has become the mainstay treatment of the most malignant brain cancer, glioblastoma multiforme (GBM). Unfortunately only a limited number of patients positively respond to it. It has been shown that zinc metal reestablishes chemosensitivity but this effect has not been tested with TMZ. Using both in vitro and in vivo experimental approaches, we investigated whether addition of zinc to TMZ enhances its cytotoxicity against GBM. In vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased with addition of zinc and this response was accompanied by an elevation of p21, PUMA, BAX and Caspase-3 expression and a decrease in growth fraction as manifested by low ki67 and lower colony formation. Analysis of GBM as intracranial xenografts in athymic mice and administration of concurrent TMZ and zinc yielded results consistent with those of the in vitro analyses. The co-treatment resulted in significant reduction in tumor volume in TMZ/zinc treated mice relative to treatment with TMZ alone. Our results suggest that zinc may serve as a potentiator of TMZ therapy in GBM patients. PMID:27556862

Zinc enhances temozolomide cytotoxicity in glioblastoma multiforme model systems.

PubMed

Toren, Amos; Pismenyuk, Tatyana; Yalon, Michal; Freedman, Shani; Simon, Amos J; Fisher, Tamar; Moshe, Itai; Reichardt, Juergen K V; Constantini, Shlomi; Mardor, Yael; Last, David; Guez, David; Daniels, Dianne; Assoulin, Moria; Mehrian-Shai, Ruty

2016-11-15

Temozolomide (TMZ) is an alkylating agent that has become the mainstay treatment of the most malignant brain cancer, glioblastoma multiforme (GBM). Unfortunately only a limited number of patients positively respond to it. It has been shown that zinc metal reestablishes chemosensitivity but this effect has not been tested with TMZ. Using both in vitro and in vivo experimental approaches, we investigated whether addition of zinc to TMZ enhances its cytotoxicity against GBM. In vitro cell viability analysis showed that the cytotoxic activity of TMZ was substantially increased with addition of zinc and this response was accompanied by an elevation of p21, PUMA, BAX and Caspase-3 expression and a decrease in growth fraction as manifested by low ki67 and lower colony formation. Analysis of GBM as intracranial xenografts in athymic mice and administration of concurrent TMZ and zinc yielded results consistent with those of the in vitro analyses. The co-treatment resulted in significant reduction in tumor volume in TMZ/zinc treated mice relative to treatment with TMZ alone. Our results suggest that zinc may serve as a potentiator of TMZ therapy in GBM patients.

Magnetic fluid hyperthermia enhances cytotoxicity of bortezomib in sensitive and resistant cancer cell lines.

PubMed

Alvarez-Berríos, Merlis P; Castillo, Amalchi; Rinaldi, Carlos; Torres-Lugo, Madeline

2014-01-01

The proteasome inhibitor bortezomib (BZ) has shown promising results in some types of cancer, but in others it has had minimal activity. Recent studies have reported enhanced efficacy of BZ when combined with hyperthermia. However, the use of magnetic nanoparticles to induce hyperthermia in combination with BZ has not been reported. This novel hyperthermia modality has shown better potentiation of chemotherapeutics over other types of hyperthermia. We hypothesized that inducing hyperthermia via magnetic nanoparticles (MFH) would enhance the cytotoxicity of BZ in BZ-sensitive and BZ-resistant cancer cells more effectively than hyperthermia using a hot water bath (HWH). Studies were conducted using BZ in combination with MFH in two BZ-sensitive cell lines (MDA-MB-468, Caco-2), and one BZ-resistant cell line (A2780) at two different conditions, ie, 43°C for 30 minutes and 45°C for 30 minutes. These experiments were compared with combined application of HWH and BZ. The results indicate enhanced potentiation between hyperthermic treatment and BZ. MFH combined with BZ induced cytotoxicity in sensitive and resistant cell lines to a greater extent than HWH under the same treatment conditions. The observation that MFH sensitizes BZ-resistant cell lines makes this approach a potentially effective anticancer therapy platform.

Acetaminophen Enhances Cisplatin- and Paclitaxel-mediated Cytotoxicity to SKOV3 Human Ovarian Carcinoma

PubMed Central

Wu, Y. Jeffrey; Neuwelt, Alexander J.; Muldoon, Leslie L.; Neuwelt, Edward A.

2013-01-01

Background Ovarian cancer is commonly treated with cisplatin/paclitaxel but many tumors become resistant. Acetaminophen reduced glutathione and enhanced chemotherapy efficacy in treating hepatic cancer. The objective of this study was to examine if acetaminophen enhances the cytotoxicity of cisplatin/paclitaxel in ovarian cancer. Materials and Methods SKOV3 human ovarian carcinoma cells in vitro and a subcutaneous tumor nude rat model were used and treated with cisplatin/paclitaxel with or without acetaminophen. Results In vitro, acetaminophen enhanced apoptosis induced by cisplatin and paclitaxel with similar effects on glutathione, reactive oxygen species and mitochondrial membrane potential but different effects on nuclear factor erythroid 2-related factor 2 (NRF2) translocation. In vivo, acetaminophen was uniformly distributed in tissue and significantly reduced hepatic glutathione. Acetaminophen enhanced cisplatin chemotherapeutic effect by reducing tumor recurrence Conclusion Our results suggest that acetaminophen as a chemoenhancing adjuvant could improve the efficacy of cisplatin and paclitaxel in treating patients with ovarian carcinoma and other tumor types. PMID:23749887

Discovery of potent cytotoxic ortho-aryl chalcones as new scaffold targeting tubulin and mitosis with affinity-based fluorescence.

PubMed

Zhu, Cuige; Zuo, Yinglin; Wang, Ruimin; Liang, Baoxia; Yue, Xin; Wen, Gesi; Shang, Nana; Huang, Lei; Chen, Yu; Du, Jun; Bu, Xianzhang

2014-08-14

A series of new ortho-aryl chalcones have been designed and synthesized. Many of these compounds were found to exhibit significant antiproliferation activity toward a panel of cancer cell lines. Selected compounds show potent cytotoxicity against several drug resistant cell lines including paclitaxel (Taxol) resistant human ovarian carcinoma cells, vincristine resistant human ileocecum carcinoma cells, and doxorubicin resistant human breast carcinoma cells. Further investigation revealed that active analogues could inhibit the microtubule polymerization by binding to colchicine site and thus induce multipolar mitosis, G2/M phase arrest, and apoptosis of cancer cells. Furthermore, affinity-based fluorescence enhancement was observed during the binding of active compounds with tubulin, which greatly facilitated the determination of tubulin binding site of the compounds. Finally, selected compound 26 was found to exhibit obvious in vivo antitumor activity in A549 tumor xenografts model. Our systematic studies implied a new scaffold targeting tubulin and mitosis for novel antitumor drug discovery.

Astaxanthin enhances pemetrexed-induced cytotoxicity by downregulation of thymidylate synthase expression in human lung cancer cells.

PubMed

Liao, Kai-Sheng; Wei, Chia-Li; Chen, Jyh-Cheng; Zheng, Hao-Yu; Chen, Wen-Ching; Wu, Chia-Hung; Wang, Tai-Jing; Peng, Yi-Shuan; Chang, Po-Yuan; Lin, Yun-Wei

2016-11-01

Pemetrexed, a multitargeted antifolate agent, has demonstrated clinical activity in non-small cell lung cancer (NSCLC) cells. Increased expression of thymidylate synthase (TS) is thought to be associated with resistance to pemetrexed. Astaxanthin exhibits a wide range of beneficial effects including anti-cancer and anti-inflammatory properties. In this study, we showed that down-regulating of TS expression in two NSCLC cell lines, human lung adenocarcinoma H1650 and squamous cell carcinoma H1703 cells, with astaxanthin were associated with decreased MKK1/2-ERK1/2 activity. Enforced expression of constitutively active MKK1 (MKK1-CA) vector significantly rescued the decreased TS mRNA and protein levels in astaxanthin-treated NSCLC cells. Combined treatment with a MKK1/2 inhibitor (U0126 or PD98059) further decreased the TS expression in astaxanthin-exposed NSCLC cells. Knockdown of TS using small interfering RNA (siRNA) or inhibiting ERK1/2 activity enhanced the cytotoxicity and cell growth inhibition of astaxanthin. Combination of pemetrexed and astaxanthin resulted in synergistic enhancing cytotoxicity and cell growth inhibition in NSCLC cells, accompanied with reduced activation of phospho-MKK1/2, phopho-ERK1/2, and TS expression. Overexpression of MKK1/2-CA reversed the astaxanthin and pemetrexed-induced synergistic cytotoxicity. Our findings suggested that the down-regulation of MKK1/2-ERK1/2-mediated TS expression by astaxanthin is an important regulator of enhancing the pemetrexed-induced cytotoxicity in NSCLC cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Improved Micellar Formulation for Enhanced Delivery for Paclitaxel.

PubMed

Xu, Jieni; Zhang, Xiaolan; Chen, Yichao; Huang, Yixian; Wang, Pengcheng; Wei, Yuan; Ma, Xiaochao; Li, Song

2017-01-03

We have previously improved the bioactivity of PEG 5k -FTS 2 system by incorporating disulfide bond (PEG 5k -S-S-FTS 2 ) to facilitate the release of farnesyl thiosalicylic acid (FTS).1 Later, fluorenylmethyloxycarbonyl (Fmoc) moiety has been introduced to PEG 5k -FTS 2 system (PEG 5k -Fmoc-FTS 2 ) in order to enhance drug loading capacity (DLC) and formulation stability.2 In this study, we have brought in both disulfide linkage and Fmoc group to PEG 5k -FTS 2 to form a simple PEG 5k -Fmoc-S-S-FTS 2 micellar system. PEG 5k -Fmoc-S-S-FTS 2 conjugate formed filamentous micelles with a ∼10-fold decrease in critical micellar concentration (CMC). Compared with PEG 5k -Fmoc-FTS 2 , our novel system exhibited further strengthened DLC and colloidal stability. More FTS was freed from PEG 5k -Fmoc-S-S-FTS 2 in treated tumor cells compared to PEG 5k -Fmoc-FTS 2 , which was correlated to an increased cytotoxicity of our new carrier in these cancer cells. After loading Paclitaxel (PTX) into PEG 5k -Fmoc-S-S-FTS 2 micelles, it showed more potent efficiency in inhibition of tumor cell proliferation than Taxol and PTX-loaded PEG 5k -Fmoc-FTS 2 . PTX release kinetics of PTX/PEG 5k -Fmoc-S-S-FTS 2 was much slower than that of Taxol and PTX/PEG 5k -Fmoc-FTS 2 in normal release medium. In contrast, in glutathione (GSH)-containing medium, PTX in PEG 5k -Fmoc-S-S-FTS 2 micelles revealed faster and more complete release. Pharmacokinetics and tissue distribution study showed that our PEG 5k -Fmoc-S-S-FTS 2 system maintained PTX in circulation for a longer time and delivered more PTX to tumor sites with less accumulation in major organs. Finally, PTX-loaded PEG 5k -Fmoc-S-S-FTS 2 micelles resulted in a superior therapeutic effect in vivo compared to Taxol and PTX formulated in PEG 5k -Fmoc-FTS 2 micelles.

Hypoxia Enhances the Antiglioma Cytotoxicity of B10, a Glycosylated Derivative of Betulinic Acid

PubMed Central

Thiepold, Anna-Luisa; Harter, Patrick N.; Reichert, Sebastian; Kögel, Donat; Paschke, Reinhard; Mittelbronn, Michel; Weller, Michael; Steinbach, Joachim P.; Fulda, Simone; Bähr, Oliver

2014-01-01

B10 is a glycosylated derivative of betulinic acid with promising activity against glioma cells. Lysosomal cell death pathways appear to be essential for its cytotoxicity. We investigated the influence of hypoxia, nutrient deprivation and current standard therapies on B10 cytotoxicity. The human glioma cell lines LN-308 and LNT-229 were exposed to B10 alone or together with irradiation, temozolomide, nutrient deprivation or hypoxia. Cell growth and viability were evaluated by crystal violet staining, clonogenicity assays, propidium iodide uptake and LDH release assays. Cell death was examined using an inhibitor of lysosomal acidification (bafilomycin A1), a cathepsin inhibitor (CA074-Me) and a short-hairpin RNA targeting cathepsin B. Hypoxia substantially enhanced B10-induced cell death. This effect was sensitive to bafilomycin A1 and thus dependent on hypoxia-induced lysosomal acidification. Cathepsin B appeared to mediate cell death because either the inhibitor CA074-Me or cathepsin B gene silencing rescued glioma cells from B10 toxicity under hypoxia. B10 is a novel antitumor agent with substantially enhanced cytotoxicity under hypoxia conferred by increased lysosomal cell death pathway activation. Given the importance of hypoxia for therapy resistance, malignant progression, and as a result of antiangiogenic therapies, B10 might be a promising strategy for hypoxic tumors like malignant glioma. PMID:24743710

Enhancement of cytotoxicity of antimicrobial peptide magainin II in tumor cells by bombesin-targeted delivery

PubMed Central

Liu, Shan; Yang, Hao; Wan, Lin; Cai, Hua-wei; Li, Sheng-fu; Li, You-ping; Cheng, Jing-qiu; Lu, Xiao-feng

2011-01-01

Aim: To investigate whether the conjugation of magainin II (MG2), an antimicrobial peptides (AMPs), to the tumor-homing peptide bombesin could enhance its cytotoxicity in tumor cells. Methods: A magainin II-bombesin conjugate (MG2B) was constructed by attaching magainin II (MG2) to bombesin at its N-terminus. The peptides were synthesized using Fmoc-chemistry. The in vitro cytotoxicity of the peptide in cancer cells was quantitatively determined using the CCK-8 cell counting kit. Moreover, the in vivo antitumor effect of the peptide was determined in tumor xenograft models. Results: The IC50 of MG2B for cancer cells (10–15 μmol/L) was at least 10 times lower than the IC50 of unconjugated MG2 (125 μmol/L). Moreover, the binding affinity of MG2B for cancer cells was higher than that of unconjugated MG2. In contrast, conjugation to a bombesin analog lacking the receptor-binding domain failed to increase the cytotoxicity of MG2, suggesting that bombesin conjugation enhances the cytotoxicity of MG2 in cancer cells through improved binding. Indeed, MG2B selectively induced cell death in cancer cells in vitro with the IC50 ranging from 10 to 15 μmol/L, which was about 6–10 times lower than the IC50 for normal cells. MG2B (20 mg/kg per day, intratumorally injected for 5 d) also exhibited antitumor effects in mice bearing MCF-7 tumor grafts. The mean weights of tumor grafts in MG2B- and PBS-treated mice were 0.21±0.05 g and 0.59±0.12 g, respectively. Conclusion: The results suggest that conjugation of AMPs to bombesin might be an alternative approach for targeted cancer therapy. PMID:21131998

Enhancement of cytotoxicity of antimicrobial peptide magainin II in tumor cells by bombesin-targeted delivery.

PubMed

Liu, Shan; Yang, Hao; Wan, Lin; Cai, Hua-wei; Li, Sheng-fu; Li, You-ping; Cheng, Jing-qiu; Lu, Xiao-feng

2011-01-01

To investigate whether the conjugation of magainin II (MG2), an antimicrobial peptides (AMPs), to the tumor-homing peptide bombesin could enhance its cytotoxicity in tumor cells. A magainin II-bombesin conjugate (MG2B) was constructed by attaching magainin II (MG2) to bombesin at its N-terminus. The peptides were synthesized using Fmoc-chemistry. The in vitro cytotoxicity of the peptide in cancer cells was quantitatively determined using the CCK-8 cell counting kit. Moreover, the in vivo antitumor effect of the peptide was determined in tumor xenograft models. The IC(50) of MG2B for cancer cells (10-15 μmol/L) was at least 10 times lower than the IC(50) of unconjugated MG2 (125 μmol/L). Moreover, the binding affinity of MG2B for cancer cells was higher than that of unconjugated MG2. In contrast, conjugation to a bombesin analog lacking the receptor-binding domain failed to increase the cytotoxicity of MG2, suggesting that bombesin conjugation enhances the cytotoxicity of MG2 in cancer cells through improved binding. Indeed, MG2B selectively induced cell death in cancer cells in vitro with the IC(50) ranging from 10 to 15 μmol/L, which was about 6-10 times lower than the IC(50) for normal cells. MG2B (20 mg/kg per day, intratumorally injected for 5 d) also exhibited antitumor effects in mice bearing MCF-7 tumor grafts. The mean weights of tumor grafts in MG2B- and PBS-treated mice were 0.21±0.05 g and 0.59±0.12 g, respectively. The results suggest that conjugation of AMPs to bombesin might be an alternative approach for targeted cancer therapy.

Curcumin enhances the mitomycin C-induced cytotoxicity via downregulation of MKK1/2-ERK1/2-mediated Rad51 expression in non-small cell lung cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ko, Jen-Chung; Department of Nursing, Yuanpei University, HsinChu, Taiwan; Graduate Institute of Technology Law, National Chiao Tung University, Taiwan

2011-09-15

Curcumin (diferuloylmethane), a major active component of turmeric (Curcuma longa), has been reported to suppress the proliferation of a wide variety of tumor cells. Rad51 is a key protein in the homologous recombination (HR) pathway of DNA double-strand break repair, and HR represents a novel target for cancer therapy. A high expression of Rad51 has been reported in chemo- or radio-resistant carcinomas. Therefore, in the current study, we will examine whether curcumin could enhance the effects of mitomycin C (MMC), a DNA interstrand cross-linking agent, to induce cytotoxicity by decreasing Rad51 expression. Exposure of two human non-small lung cancer (NSCLC)more » cell lines (A549 and H1975) to curcumin could suppress MMC-induced MKK1/2-ERK1/2 signal activation and Rad51 protein expression. Enhancement of ERK1/2 activation by constitutively active MKK1/2 (MKK1/2-CA) increased Rad51 protein levels in curcumin and MMC co-treated human lung cells. Moreover, the synergistic cytotoxic effect induced by curcumin combined with MMC was decreased by MKK1-CA-mediated enhancement of ERK1/2 activation by a significant degree. In contrast, MKK1/2 inhibitor, U0126 was shown to augment the cytotoxicity of curcumin and MMC through downregulation of ERK1/2 activation and Rad51 expression. Depletion of endogenous Rad51 expression by siRad51 RNA transfection significantly enhanced MMC and/or curcumin induced cell death and cell growth inhibition. In contrast, an overexpression of Rad51 protected lung cancer cells from synergistic cytotoxic effects induced by curcumin and MMC. We concluded that Rad51 inhibition may be an additional action mechanism for enhancing the chemosensitization of MMC by curcumin in NSCLC. - Highlights: > Curcumin downregulates MKK-ERK-mediated Rad51 expression. > Curcumin enhances mitomycin C-induced cytotoxicity. > Rad51 protects cells from cytotoxic effects induced by curcumin and mitomycin C. > Rad51 inhibition enhances the chemosensitization of

Evaluation of cytotoxicity and radiation enhancement using 1.9 nm gold particles: potential application for cancer therapy

PubMed Central

Butterworth, K T; Coulter, J A; Jain, S; Forker, J; McMahon, S J; Schettino, G; Prise, K M; Currell, F J; Hirst, D G

2010-01-01

High atomic number (Z) materials such as gold preferentially absorb kilovoltage x-rays compared to soft tissue and may be used to achieve local dose enhancement in tumours during treatment with ionizing radiation. Gold nanoparticles have been demonstrated as radiation dose enhancing agents in vivo and in vitro. In the present study, we used multiple endpoints to characterize the cellular cytotoxic response of a range of cell lines to 1.9 nm gold particles and measured dose modifying effects following transient exposure at low concentrations. Gold nanoparticles caused significant levels of cell type specific cytotoxicity, apoptosis and increased oxidative stress. When used as dose modifying agents, dose enhancement factors varied between the cell lines investigated with the highest enhancement being 1.9 in AGO-1522B cells at a nanoparticle concentration of 100 μg ml−1. This study shows exposure to 1.9 nm gold particles to induce a range of cell line specific responses including decreased clonogenic survival, increased apoptosis and induction of DNA damage which may be mediated through the production of reactive oxygen species. This is the first study involving 1.9 nm nanometre sized particles to report multiple cellular responses which impact on the radiation dose modifying effect. The findings highlight the need for extensive characterization of responses to gold nanoparticles when assessing dose enhancing potential in cancer therapy. PMID:20601762

Rapamycin enhances docetaxel-induced cytotoxicity in a androgen-independent prostate cancer xenograft model by survivin downregulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morikawa, Yasuyuki, E-mail: yasu-m@med.gunma-u.ac.jp; Koike, Hidekazu; Sekine, Yoshitaka

Highlights: Black-Right-Pointing-Pointer Rapamycin (RPM) enhances the susceptibility of PC3 cells to docetaxel. Black-Right-Pointing-Pointer Low-dosage of docetaxel (DTX) did not reduce survivin expression levels in PC3 cells. Black-Right-Pointing-Pointer Combination treatment of RPM with DTX suppressed the expression of surviving. Black-Right-Pointing-Pointer SiRNA against survivin enhanced the susceptibility of PC3 cells to DTX. Black-Right-Pointing-Pointer RPM and DTX cotreatment inhibited PC3 cell growth and decreased surviving in vivo. -- Abstract: Background: Docetaxel is a first-line treatment choice in castration-resistant prostate cancer (CRPC). However, the management of CRPC remains an important challenge in oncology. There have been many reports on the effects of rapamycin, whichmore » is an inhibitor of the mammalian target of rapamycin (mTOR), in the treatment of carcinogenesis. We assessed the cytotoxic effects of the combination treatment of docetaxel and rapamycin in prostate cancer cells. Furthermore, we examined the relationship between these treatments and survivin, which is a member of the inhibitory apoptosis family. Methods: Prostate cancer cells were cultured and treated with docetaxel and rapamycin. The effects on proliferation were evaluated with the MTS assay. In addition, we evaluated the effect on proliferation of the combination treatment induced knockdown of survivin expression by small interfering RNA transfection and docetaxel. Protein expression levels were assayed using western blotting. PC3 cells and xenograft growth in nude mice were used to evaluate the in vivo efficacy of docetaxel and its combination with rapamycin. Results: In vitro and in vivo, the combination of rapamycin with docetaxel resulted in a greater inhibition of proliferation than treatment with rapamycin or docetaxel alone. In addition, in vitro and in vivo, rapamycin decreased basal surviving levels, and cotreatment with docetaxel further decreased these

Effect of citral on the cytotoxicity of doxorubicin in human B-lymphoma cells.

PubMed

Dangkong, Darinee; Limpanasithikul, Wacharee

2015-02-01

Doxorubicin is a chemotherapy agent used in non-Hodgkin's lymphoma but side effects limit its use. Citral is a mixture of neral and geranial found in essential oils of lemon grass. We evaluated the activity of citral, doxorubicin, and combination on cytotoxicity, apoptosis, and anti-proliferative effects using human lymphoma Ramos cells. Cells were treated with doxorubicin alone or in combination with citral (10, 20, and 40 μM). Cytotoxic and apoptosis studies were done after 24 and 18 h incubations, respectively. Cytotoxic effects of citral on normal human peripheral blood mononuclear cells (PBMCs) were also investigated for its safety. Changes in the expression of BCL-2 family genes were analyzed by quantitative RT-PCR. Citral had cytotoxicity on cells with an IC50 value of 77.19 ± 4.95 µM. Citral at concentrations of 10, 20, and 40 µM additively increased the cytotoxic and apoptotic effects of doxorubicin, leading to decreased IC50 (µM) of the drug from 2.50 ± 0.01 to 2.16 ± 0.03, 1.90 ± 0.04, and 1.23 ± 0.04, respectively. Enhanced cytotoxicity was not observed in normal human PBMCs. Citral (40 µM) in combination with doxorubicin (1.5 µM) increased the expression of pro-apoptotic protein BAK but significantly decreased the expression of anti-apoptotic protein BCL-XL to 5.26-fold compared with doxorubicin-treated cells. It did not change the anti-proliferative activity of drug. Citral potentiated cytotoxicity of doxorubicin by increasing apoptotic effects. We conclude that citral may have beneficial effects in patients with B cell lymphoma treated with chemotherapy.

Surface modification of paclitaxel-loaded tri-block copolymer PLGA- b-PEG- b-PLGA nanoparticles with protamine for liver cancer therapy

NASA Astrophysics Data System (ADS)

Gao, Nansha; Chen, Zhihong; Xiao, Xiaojun; Ruan, Changshun; Mei, Lin; Liu, Zhigang; Zeng, Xiaowei

2015-08-01

In order to enhance the therapeutic effect of chemotherapy on liver cancer, a biodegradable formulation of protamine-modified paclitaxel-loaded poly(lactide- co-glycolide)- b-poly(ethylene glycol)- b-poly(lactide- co-glycolide) (PLGA- b-PEG- b-PLGA) nanoparticles (PTX-loaded/protamine NPs) was prepared. Tri-block copolymer PLGA- b-PEG- b-PLGA was synthesized by ring-opening polymerization and characterized by 1H NMR spectroscopy and gel permeation chromatography. PTX-loaded and PTX-loaded/protamine NPs were characterized in terms of size, size distribution, zeta potential, surface morphology, drug encapsulation efficiency, and drug release. Confocal laser scanning microscopy showed that coumarin 6-loaded/protamine NPs were internalized by hepatocellular carcinoma cell line HepG2. The cellular uptake efficiency of NPs was obviously elevated after protamine modification. With commercial formulation Taxol® as the reference, HepG2 cells were also used to study the cytotoxicity of the NPs. PTX-loaded/protamine NPs exhibited significantly higher cytotoxicity than PTX-loaded NPs and Taxol® did. All the results suggested that surface modification of PTX-loaded PLGA- b-PEG- b-PLGA NPs with protamine boosted the therapeutic efficacy on liver cancer.

[Immunomodulators of microbial origin enhance cytotoxicity of human mononuclear leukocytes and reduce metastatic progression of Lewis lung carcinoma in mice].

PubMed

Akhmatova, N K; Semenova, I B; Donenko, F V; Kiselevskiĭ, M V; Kurbatova, E A; Egorova, N B

2006-01-01

Effect of immunomodulators for microbial origin on innate immunity and antitumor system was continued to study. Immunomodificator Immunovac VP-4, purified staphylococcal toxoid and glucosaminyl muramyl dipeptide (GMDP) equally enhanced cytotoxicity of mononuclear leukocytes of peripheral blood of healthy donors. Index of cytotoxicity was 2.78, 2.77 and 2.70 respectively. Reduced metastatic progression of Lewis lung carcinoma in mice was observed after Immunovac VP-4 and GMDP administration. Effectiveness was seen when preparations administered according to schedules including their administration before implantation of the tumor. If preparations were administered number of metastases reduced in 4.4-5.6 times and size of metastases reduced in 7-10 times. Interplay between antitumor activity of studied immunomodulators and cytotoxic activity of NK-cells, which are base effectors of antitumor immune response, are discussed.

Oridonin enhances the cytotoxicity of 5-FU in renal carcinoma cells by inducting necroptotic death.

PubMed

Zheng, Wei; Zhou, Chun-Yan; Zhu, Xin-Qing; Wang, Xue-Jian; Li, Zi-Yao; Chen, Xiao-Chi; Chen, Feng; Che, Xiang-Yu; Xie, Xin

2018-06-26

5-fluorouracil (5-FU) is widely used for the treatment of renal carcinoma. However, drug resistance remains the reason for failure of chemotherapy. Oridonin, extracted from Chinese herb medicine, displays anti-tumor effect in several types of cancer. Whether oridonin could enhance the effect of 5-FU in renal carcinoma has not been studied. 786-O cells were used in the current study. Cell death was measured by MTT assay or live- and dead-cell staining assay. Glutathione (GSH) level was examined by ELISA. Necroptosis was identified by protein levels of receptors interaction protein-1 (RIP-1) and RIP-3, lactate dehydrogenase (LDH) and high mobility group box-1 protein (HMGB1) release, and poly [ADP-ribose] polymerase-1 (Parp-1) activity. Using a xenograft assay in nude mice, we tested the anti-tumor effects of the oridonin combined with 5-FU. 5-FU only induced apoptosis in 786-O cells. Oridonin activated both apoptosis and necroptosis in 786-O cells. Oridonin-induced necroptosis was reversed by addition of GSH or its precursorN-acetylcysteine (NAC). Oridonin-induced necroptosis was associated by activated JNK, p38, and ERK in 786-O cells, which were abolished by GSH or NAC treatment. However, JNK, p38, and ERK inhibitors showed no effect on oridonin induced-cell death. GSH or NAC treatment partly abolished the synergistic effects of oridonin and 5-FU on cell death. Oridonin enhanced the cytotoxicity of 5-FU both in vitro and in vivo. Oridonin enhances the cytotoxicity of 5-FU in renal cancer cells partially through inducing necroptosis, providing evidence of using necroptosis inducers in combination with chemotherapeutic agents for cancer treatment. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Effect of Toxoplasma lysate antigen (TLA) on feline cytotoxicity against FeLV positive lymphoma cells.

PubMed

Yang, M P; Goitsuka, R; Ono, K; Suzuki, N; Hasegawa, A

1990-08-01

The cytotoxic activities of feline spleen cells treated with Toxoplasma lysate antigen (TLA) were assayed against feline leukemia virus (FeLV)-producing lymphoma. FL74 cells, and xenogeneic target lymphoma, mouse YAC-1 cells. The TLA treatments were performed in vivo alone, in vitro alone, and in vivo plus in vitro, respectively. In vivo plus in vitro treatments with TLA induced a marked augmentation in cytotoxic activity of spleen cells to FL74 cells. The treatment with TLA in vivo alone showed an enhancement of cytotoxic activity but in vitro alone did not. The cytotoxic effects of TLA-treated spleen cells obtained from the cats which had been previously immunized with live FL74 cells were similar to those of spleen cells from non-immunized cats treated with TLA. However, no increase of cytotoxicity was shown in the response to mouse YAC-1 cells regardless of TLA treatments. These results indicated that the in vivo TLA treatment augmented the cytotoxicity of feline spleen cells against FeLV-producing lymphoma cell.

The selective cytotoxicity elicited by phytochemical extract from Senecio graveolens (Asteraceae) on breast cancer cells is enhanced by hypoxia.

PubMed

Echiburú-Chau, Carlos; Alfaro-Lira, Susana; Brown, Nelson; Salas, Cristian O; Cuellar, Mauricio; Santander, Javier; Ogalde, Juan Pablo; Rothhammer, Francisco

2014-04-01

Breast cancer is the second cause of cancer‑related deaths in woman and the incidence of the disease has increased worldwide, in part due to improvements in early detection. Several drugs with anticancer effects have been extracted from plants in the last 20 years, many of which are particularly effective against breast cancer cells. In particular, we have become interested in the ethanolic extract from Senecio graveolens (synonym of S. nutans), a plant commonly called Chachacoma, in an effort to isolate compounds that could demonstrate cytotoxic effects on breast cancer cells. Senecio (Asteraceae) is the largest gender in Chile comprising approximatly 200 species. These herbs inhabit areas over 3,500 meters above the sea level in the Andes Mountains. S. graveolens is commonly used by local communities for its medicinal properties, particularly its capacity to ameliorate high-altitude-associated sickness. The cytotoxic effect of the alcoholic extract from S. graveolens, as well as its most abundant compound 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone, were tested in the breast cancer cell lines ZR-75-1, MCF-7 and MDA-MB‑231, and non-tumorigenic MCF-10F cells. We show that the phytochemical extract was able to induce cytotoxicity in cancer cells but not in MCF-10F. Importantly, this effect was enhanced under hypoxic conditions. However, 4-hydroxy-3-(3-methyl-2-butenyl)acetophenone, the main compound, did not by itself show an effective anticarcinogenic activity in comparison to the whole extract. Interestingly, the cytotoxic effect of the phytochemical extract was dependent on the basal MnSOD protein expression. Thus, cytotoxicity was increased when MnSOD levels were low, but resistance was evident when protein levels were high. Additionally, the crude extract seems to trigger cell death by a variety of processes, including autophagy, apoptosis and necrosis, in MCF-7 cells. In summary, S. graveolens extract possess anticancer activity displaying a specific

High-Content, High-Throughput Screening for the Identification of Cytotoxic Compounds Based on Cell Morphology and Cell Proliferation Markers

PubMed Central

Martin, Heather L.; Adams, Matthew; Higgins, Julie; Bond, Jacquelyn; Morrison, Ewan E.; Bell, Sandra M.; Warriner, Stuart; Nelson, Adam; Tomlinson, Darren C.

2014-01-01

Toxicity is a major cause of failure in drug discovery and development, and whilst robust toxicological testing occurs, efficiency could be improved if compounds with cytotoxic characteristics were identified during primary compound screening. The use of high-content imaging in primary screening is becoming more widespread, and by utilising phenotypic approaches it should be possible to incorporate cytotoxicity counter-screens into primary screens. Here we present a novel phenotypic assay that can be used as a counter-screen to identify compounds with adverse cellular effects. This assay has been developed using U2OS cells, the PerkinElmer Operetta high-content/high-throughput imaging system and Columbus image analysis software. In Columbus, algorithms were devised to identify changes in nuclear morphology, cell shape and proliferation using DAPI, TOTO-3 and phosphohistone H3 staining, respectively. The algorithms were developed and tested on cells treated with doxorubicin, taxol and nocodazole. The assay was then used to screen a novel, chemical library, rich in natural product-like molecules of over 300 compounds, 13.6% of which were identified as having adverse cellular effects. This assay provides a relatively cheap and rapid approach for identifying compounds with adverse cellular effects during screening assays, potentially reducing compound rejection due to toxicity in subsequent in vitro and in vivo assays. PMID:24505478

Endophytic Fungi—Alternative Sources of Cytotoxic Compounds: A Review

PubMed Central

Uzma, Fazilath; Mohan, Chakrabhavi D.; Hashem, Abeer; Konappa, Narasimha M.; Rangappa, Shobith; Kamath, Praveen V.; Singh, Bhim P.; Mudili, Venkataramana; Gupta, Vijai K.; Siddaiah, Chandra N.; Chowdappa, Srinivas; Alqarawi, Abdulaziz A.; Abd_Allah, Elsayed F.

2018-01-01

Cancer is a major cause of death worldwide, with an increasing number of cases being reported annually. The elevated rate of mortality necessitates a global challenge to explore newer sources of anticancer drugs. Recent advancements in cancer treatment involve the discovery and development of new and improved chemotherapeutics derived from natural or synthetic sources. Natural sources offer the potential of finding new structural classes with unique bioactivities for cancer therapy. Endophytic fungi represent a rich source of bioactive metabolites that can be manipulated to produce desirable novel analogs for chemotherapy. This review offers a current and integrative account of clinically used anticancer drugs such as taxol, podophyllotoxin, camptothecin, and vinca alkaloids in terms of their mechanism of action, isolation from endophytic fungi and their characterization, yield obtained, and fungal strain improvement strategies. It also covers recent literature on endophytic fungal metabolites from terrestrial, mangrove, and marine sources as potential anticancer agents and emphasizes the findings for cytotoxic bioactive compounds tested against specific cancer cell lines. PMID:29755344

Circumvention of Taxol-Resistance in Human Breast Cancers by Improved Water Soluble Taxanes

DTIC Science & Technology

2001-10-01

possible roles of interferon alpha, tumor necrosis factor alpha and transforming growth factor beta in Mn-SOD induction by polysaccharide K. Cancer ...chemoembolization in combination with local hyperthermia. Japanese Journal of Cancer & Chemotherapy. 16:2957-2960 61. Kidd P. (2000) The use of mushroom glucans ...Circumvention of Taxol-Resistance in Human Breast Cancers by Improved Water Soluble Taxanes PRINCIPAL INVESTIGATOR: Li-Xi Yang, M.D., Ph.D. CONTRACTING

The effect of bicarbonate on menadione-induced redox cycling and cytotoxicity: potential involvement of the carbonate radical.

PubMed

Aljuhani, Naif; Michail, Karim; Karapetyan, Zubeida; Siraki, Arno G

2013-10-01

We have investigated the effect of NaHCO3 on menadione redox cycling and cytotoxicity. A cell-free system utilized menadione and ascorbic acid to catalyze a redox cycle, and we utilized murine hepatoma (Hepa 1c1c7) cells for in vitro experiments. Experiments were performed using low (2 mmol/L) and physiological (25 mmol/L) levels of NaHCO3 in buffer equilibrated to physiological pH. Using oximetry, ascorbic acid oxidation, and ascorbyl radical detection, we found that menadione redox cycling was enhanced by NaHCO3. Furthermore, Hepa 1c1c7 cells treated with menadione demonstrated cytotoxicity that was significantly increased with physiological concentrations of NaHCO3 in the media, compared with low levels of NaHCO3. Interestingly, the inhibition of superoxide dismutase (SOD) with 2 different metal chelators was associated with a protective effect against menadione cytotoxicity. Using isolated protein, we found a significant increase in protein carbonyls with menadione-ascorbate-SOD with physiological NaHCO3 levels; low NaHCO3 or SOD-free reactions produced lower levels of protein carbonyls. In conclusion, these findings suggest that the hydrogen peroxide generated by menadione redox cycling together with NaHCO3-CO2 are potential substrates for SOD peroxidase activity that can lead to carbonate-radical-enhanced cytotoxicity. These findings demonstrate the importance of NaHCO3 in menadione redox cycling and cytotoxicity.

Montelukast is a potent and durable inhibitor of multidrug resistance protein 2 (MRP2)-mediated efflux of taxol and saquinavir

PubMed Central

Roy, Upal; Chakravarty, Geetika; Honer Zu Bentrup, Kerstin; Mondal, Debasis

2009-01-01

The ATP binding cassette (ABC)-transporters are energy dependent efflux pumps which regulate the pharmacokinetics of both anti-cancer chemotherapeutic agents, e.g. taxol, and of HIV-1 protease inhibitors (HPIs), e.g. saquinavir. Increased expression of several ABC-transporters, especially P-gp and MRP2, are observed in multidrug resistant (MDR) tumor cells and on HIV-1 infected lymphocytes. In addition, due to their apical expression on vascular endothelial barriers, both P-gp and MRP2 are of crucial importance towards dictating drug access into sequestered tissues. However, although a number of P-gp inhibitors are currently in clinical trials, possible inhibitors of MRP2 are not being thoroughly investigated. The experimental leukotriene receptor antagonist (LTRA), MK-571 is known to be a potent inhibitor of MRP transporters. Using the MRP2 over-expressing cell line, MDCKII-MRP2, we evaluated whether the clinically approved LTRAs, e.g. montelukast (Singulair™) and zafirlukast (Accolate™), can similarly suppress MRP2-mediated efflux. We compared the efficacy of increasing concentrations (20-100 μM) of MK-571, montelukast, and zafirlukast, in suppressing the efflux of calcein-AM, a fluorescent MRP substrate, and the radiolabeled [3H-] drugs, taxol and saquinavir. Montelukast was the most potent inhibitor (p<0.01) of MRP2-mediated efflux of all three substrates. Montelukast also increased (p<0.01) the duration of intracellular retention of both taxol and saquinavir. More than 50% of the drugs were retained in cells even after 90 mins post removal of montelukast from the medium. Our findings implicate that montelukast, a relatively safe anti-asthmatic agent, may be used as an adjunct therapy to suppress the efflux of taxol and saquinavir from MRP2 overexpressing cells. PMID:19952419

Au@Pt nanoparticles as catalase mimics to attenuate tumor hypoxia and enhance immune cell-mediated cytotoxicity

NASA Astrophysics Data System (ADS)

Liang, Hong; Wu, Ying; Ou, Xiang-Yu; Li, Jing-Ying; Li, Juan

2017-11-01

Hypoxic tumor microenvironment (TME) is closely linked to tumor progression, heterogeneity and immune suppression. Therefore, the development of effective methods to overcome hypoxia and substantially enhance the immunotherapy efficacy remains a desirable goal. Herein, we engineered a biocompatible Au core/Pt shell nanoparticles (Au@Pt NPs) to reoxygenate the TME by reacting with endogenous H2O2. Treatment with Au@Pt NPs appeared to improve oxygen in intracellular environments and decrease hypoxia-inducible factor-1α expression. Furthermore, the integration of high catalytic efficiency of Au@Pt NPs with cytokine-induced killer (CIK) cell immunotherapy, could lead to significantly improve the effect of CIK cell-mediated cytotoxicity. These results suggest great potential of Au@Pt NPs for regulation of the hypoxic TME and enhance immune cell mediated anti-tumor immunity.

Characterization of Thermally Activated Metalloenediyne Cytotoxicity in Human Melanoma Cells.

PubMed

Keller, Eric J; Porter, Meghan; Garrett, Joy E; Varie, Meredith; Wang, Haiyan; Pollok, Karen E; Turchi, John J; Zaleski, Jeffrey M; Dynlacht, Joseph R

2018-05-15

ED, platinated PyED (Pt-PyED). Pt-PyED binds to DNA-like cisplatin, and much like PyED, cytotoxicity is greatly enhanced after treatment with the drug at elevated temperatures. However, in contrast to PyED, Pt-PyED is only minimally cytotoxic at 37°C, at concentrations at which cytotoxicity is enhanced by hyperthermia. Further development of cisplatin-based enediynes may result in compounds which, when activated, will possess multiple DNA binding modalities similar to cisplatin, but produce less side effects in tissues at normothermic temperatures.

Effect of Aerva lanata on cell-mediated immune responses and cytotoxic T-lymphocyte generation in normal and tumor-bearing mice.

PubMed

Siveen, K S; Kuttan, Girija

2012-01-01

Cell-mediated immunity offers protection against virus-infected cells and tumor cells, involves activation of natural killer (NK) cells, production of antigen-specific cytotoxic T-lymphocytes, and release of various cytokines in response to an antigen. Administration of an ethanolic extract of Aerva lanata was found to stimulate cell-mediated immunological responses in normal and tumor-bearing BALB/c mice. A significant enhancement in NK cell activity in both normal and tumor-bearing hosts was observed after administration of A. lanata. Antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent complement-mediated cytotoxicity (ACC) were significantly enhanced as well in both sets of treated hosts. In addition, in vivo production of IL-2 and IFNg were each significantly enhanced by extract treatment. The stimulatory effect of A. lanata on cytotoxic T-lymphocyte (CTL) production was determined by Winn's neutralization assay using CTL-sensitive EL4 thymoma cells. A. lanata treatment caused a significant increase in CTL production in both in vivo and in vitro models, in each case as indicated by a significant increase in the life-spans of tumor-injected mice. Taken together, all of these results in the murine model indicate that administration of an ethanolic extract of A. lanata could enhance the cell-mediated anti-tumor response.

PLGA-soya lecithin based micelles for enhanced delivery of methotrexate: Cellular uptake, cytotoxic and pharmacokinetic evidences.

PubMed

Singh, Anupama; Thotakura, Nagarani; Kumar, Rajendra; Singh, Bhupinder; Sharma, Gajanand; Katare, Om Prakash; Raza, Kaisar

2017-02-01

Biocompatible and biodegradable polymers like PLGA have revolutionized the drug delivery approaches. However, poor drug loading and substantially high lipophilicity, pave a path for further tailing of this promising agent. In this regard, PLGA was feathered with biocompatible phospholipid and polymeric micelles were developed for delivery of Methotrexate (MTX) to cancer cells. The nanocarriers (114.6nm±5.5nm) enhanced the cytotoxicity of MTX by 2.13 folds on MDA-MB-231 cells. Confocal laser scanning microscopy confirmed the increased intracellular delivery. The carrier decreased the protein binding potential and enhanced the bioavailable fraction of MTX. Pharmacokinetic studies vouched substantial enhancement in AUC and bioresidence time, promising an ideal carrier to effectively deliver the drug to the site of action. The developed nanocarriers offer potential to deliver the drug in the interiors of cancer cells in an effective manner for improved therapeutic action. Copyright © 2016 Elsevier B.V. All rights reserved.

Participation of MT3 melatonin receptors in the synergistic effect of melatonin on cytotoxic and apoptotic actions evoked by chemotherapeutics.

PubMed

Pariente, Roberto; Bejarano, Ignacio; Espino, Javier; Rodríguez, Ana B; Pariente, José A

2017-11-01

Melatonin has antitumor activity via several mechanisms including its antiproliferative and proapoptotic effects in addition to its potent antioxidant actions. Therefore, melatonin may be useful in the treatment of tumors in association with chemotherapy drugs. This study was performed to study the role of melatonin receptors on the cytotoxicity and apoptosis induced by the chemotherapeutic agents cisplatin and 5-fluorouracil in two tumor cell lines, such as human colorectal cancer HT-29 cells and cervical cancer HeLa cells. We found that both melatonin and the two chemotherapeutic agents tested induced a decrease in HT-29 and HeLa cell viability. Furthermore, melatonin significantly increased the cytotoxic effect of chemotherapeutic agents, particularly, in 5-fluorouracil-challenged cells. Stimulation of cells with either of the two chemotherapeutic agents in the presence of melatonin further increased caspase-3 activation. Concomitant treatments with melatonin and chemotherapeutic agents augmented the population of apoptotic cells compared to the treatments with chemotherapeutics alone. Blockade of MT1 and/or MT2 receptors with luzindole or 4-P-PDOT was unable to reverse the enhancing effects of melatonin on both cytotoxicity, caspase-3 activation and the amount of apoptotic cells evoked by the chemotherapeutic agents, whereas when MT3 receptors were blocked with prazosin, the synergistic effect of melatonin with chemotherapy on cytotoxicity and apoptosis was reversed. Our findings provided evidence that in vitro melatonin strongly enhances chemotherapeutic-induced cytotoxicity and apoptosis in two tumor cell lines, namely HT-29 and HeLa cells and, this potentiating effect of melatonin is mediated by MT3 receptor stimulation.

Native or Proteolytically Activated NanI Sialidase Enhances the Binding and Cytotoxic Activity of Clostridium perfringens Enterotoxin and Beta Toxin.

PubMed

Theoret, James R; Li, Jihong; Navarro, Mauricio A; Garcia, Jorge P; Uzal, Francisco A; McClane, Bruce A

2018-01-01

Many Clostridium perfringens strains produce NanI as their major sialidase. Previous studies showed that NanI could potentiate C. perfringens epsilon toxin cytotoxicity by enhancing the binding of this toxin to host cells. The present study first determined that NanI exerts similar cytotoxicity-enhancing effects on C. perfringens enterotoxin and beta toxin, which are also important toxins for C. perfringens diseases (enteritis and enterotoxemia) originating in the gastrointestinal (GI) tract. Building upon previous work demonstrating that purified trypsin can activate NanI activity, this study next determined that purified chymotrypsin or mouse intestinal fluids can also activate NanI activity. Amino acid sequencing then showed that this effect involves the N-terminal processing of the NanI protein. Recombinant NanI (rNanI) species corresponding to major chymotrypsin- or small intestinal fluid-generated NanI fragments possessed more sialidase activity than did full-length rNanI, further supporting the proteolytic activation of NanI activity. rNanI species corresponding to proteolysis products also promoted the cytotoxic activity and binding of enterotoxin and beta toxin more strongly than did full-length rNanI. Since enterotoxin and beta toxin are produced in the intestines during human and animal disease, these findings suggest that intestinal proteases may enhance NanI activity, which in turn could further potentiate the activity of intestinally active toxins during disease. Coupling these new results with previous findings demonstrating that NanI is important for the adherence of C. perfringens to enterocyte-like cells, NanI sialidase is now emerging as a potential auxiliary virulence factor for C. perfringens enteritis and enterotoxemia. Copyright © 2017 American Society for Microbiology.

Auxotrophic recombinant Mycobacterium bovis BCG overexpressing Ag85B enhances cytotoxicity on superficial bladder cancer cells in vitro.

PubMed

Begnini, Karine Rech; Rizzi, Caroline; Campos, Vinicius Farias; Borsuk, Sibele; Schultze, Eduarda; Yurgel, Virginia Campello; Nedel, Fernanda; Dellagostin, Odir Antônio; Collares, Tiago; Seixas, Fabiana Kömmling

2013-02-01

BCG therapy remains at the forefront of immunotherapy for treating patients with superficial bladder cancer. The high incidence of local side effects and the presence of non-responder diseases have led to efforts to improve the therapy. Hence, we proposed that an auxotrophic recombinant BCG strain overexpressing Ag85B (BCG ∆leuD/Ag85B), could enhance the cytotoxicity to the human bladder carcinoma cell line 5637. The rBCG was generated using an expression plasmid encoding the mycobacterial antigen Ag85B to transform a BCG ∆leuD strain. The inhibitory effect of BCG ∆leuD/Ag85B on 5637 cells was determined by the MTT method, morphology observation and a LIVE/DEAD assay. Gene expression profiles for apoptotic, cell cycle-related and oxidative stress-related genes were investigated by qRT-PCR. Bax, bcl-2 and p53 induction by BCG ∆leuD/Ag85B treatment was evaluated by Western blotting. BCG ∆leuD/Ag85B revealed a superior cytotoxicity effect compared to the control strains used in this study. The results showed that the expression level of pro-apoptotic and cell cycle-related genes increased after BCG ∆leuD/Ag85B treatment, whereas the mRNA levels of anti-apoptotic genes decreased. Interestingly, BCG ∆leuD/Ag85B also increased the mRNA level of antioxidant enzymes in the bladder cancer cell line. Bax and p53 proteins levels increased following treatment. In conclusion, these results suggest that treatment with BCG ∆leuD/Ag85B enhances cytotoxicity for superficial bladder cancer cells in vitro. Therefore, rBCG therapy may have potential benefits in the treatment of bladder cancer.

Down-Regulation of Glucose-Regulated Protein (GRP) 78 Potentiates Cytotoxic Effect of Celecoxib in Human Urothelial Carcinoma Cells

PubMed Central

Huang, Kuo-How; Kuo, Kuan-Lin; Chen, Shyh-Chyan; Weng, Te-I; Chuang, Yuan-Ting; Tsai, Yu-Chieh; Pu, Yeong-Shiau; Chiang, Chih-Kang; Liu, Shing-Hwa

2012-01-01

Celecoxib is a selective cyclooxygenase-2 (COX-2) inhibitor that has been reported to elicit anti-proliferative response in various tumors. In this study, we aim to investigate the antitumor effect of celecoxib on urothelial carcinoma (UC) cells and the role endoplasmic reticulum (ER) stress plays in celecoxib-induced cytotoxicity. The cytotoxic effects were measured by MTT assay and flow cytometry. The cell cycle progression and ER stress-associated molecules were examined by Western blot and flow cytometry. Moreover, the cytotoxic effects of celecoxib combined with glucose-regulated protein (GRP) 78 knockdown (siRNA), (−)-epigallocatechin gallate (EGCG) or MG132 were assessed. We demonstrated that celecoxib markedly reduces the cell viability and causes apoptosis in human UC cells through cell cycle G1 arrest. Celecoxib possessed the ability to activate ER stress-related chaperones (IRE-1α and GRP78), caspase-4, and CCAAT/enhancer binding protein homologous protein (CHOP), which were involved in UC cell apoptosis. Down-regulation of GRP78 by siRNA, co-treatment with EGCG (a GRP78 inhibitor) or with MG132 (a proteasome inhibitor) could enhance celecoxib-induced apoptosis. We concluded that celecoxib induces cell cycle G1 arrest, ER stress, and eventually apoptosis in human UC cells. The down-regulation of ER chaperone GRP78 by siRNA, EGCG, or proteosome inhibitor potentiated the cytotoxicity of celecoxib in UC cells. These findings provide a new treatment strategy against UC. PMID:22438966

Enhancement of doxorubicin cytotoxicity of human cancer cells by tyrosine kinase inhibition of insulin receptor and type I IGF receptor

PubMed Central

Zeng, Xianke; Zhang, Hua; Oh, Annabell; Zhang, Yan; Yee, Douglas

2015-01-01

The type I insulin-like growth factor receptor (IGF1R) contributes to cancer cell biology. Disruption of IGF1R signaling alone or in combination with cytotoxic agents has emerged as a new therapeutic strategy. Our laboratory has shown that sequential treatment with doxorubicin (DOX) and anti-IGF1R antibodies significantly enhanced the response to chemotherapy. In this study, we examined whether inhibition of the tyrosine kinase activity of this receptor family would also enhance chemotherapy response. Cis-3-[3-(4-methyl-piperazin-l-yl)-cyclobutyl]-1-(2-phenyl-quinolin-7-yl)-imidazo[1,5-a]pyrazin-8-ylamine (PQIP) inhibited IGF1R and insulin receptor (InsR) kinase activity and downstream activation of ERK1/2 and Akt in MCF-7 and LCC6 cancer cells. PQIP inhibited both monolayer growth and anchorage-independent growth in a dose-dependent manner. PQIP did not induce apoptosis, but rather, PQIP treatment was associated with an increase in autophagy. We examined whether sequential or combination therapy of PQIP with DOX could enhance growth inhibition. PQIP treatment together with DOX or DOX followed by PQIP significantly inhibited anchorage-independent growth in MCF-7 and LCC6 cells compared to single agent alone. In contrast, pre-treatment with PQIP followed by DOX did not enhance the cytotoxicity of DOX in vitro. Furthermore, OSI-906, a PQIP derivative, inhibited IGF-I signaling in LCC6 xenograft tumors in vivo. When given once a week, simultaneous administration of OSI-906 and DOX significantly enhanced the anti-tumor effect of DOX. In summary, these results suggest that timing and duration of the IGF1R/InsR tyrosine kinase inhibitors with chemotherapeutic agents should be evaluated in clinical trials. Long-term disruption of IGF1R/InsR may not be necessary when combined with cytotoxic chemotherapy. PMID:21850397

Cytotoxic effect of disulfiram/copper on human glioblastoma cell lines and ALDH-positive cancer-stem-like cells

PubMed Central

Liu, P; Brown, S; Goktug, T; Channathodiyil, P; Kannappan, V; Hugnot, J-P; Guichet, P-O; Bian, X; Armesilla, A L; Darling, J L; Wang, W

2012-01-01

Background: Glioblastoma multiforme (GBM) cells are resistant to anticancer drugs. Cancer stem cells (CSCs) are a key mediator of chemoresistance. We have reported that disulfiram (DS), an aldehyde dehydrogenase (ALDH) inhibitor, targets breast CSC-like cells. In this study, the effect of DS and combination of DS and gemcitabine (dFdC) on GBM cells and GBM stem-like cells was investigated. Methods: 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI)-isobologram, western blot, luciferase reporter gene assay, electrophoretic mobility-shift assay and ALDH analysis were used in this study. Results: Disulfiram is cytotoxic in GBM cell lines in a copper (Cu)-dependent manner. Disulfiram/copper enhances the cytotoxicity of dFdC. Combination index-isobologram analysis indicates a synergistic effect between DS/Cu and dFdC. Disulfiram/copper induces reactive oxygen species (ROS), activates JNK and p38 pathways and inhibits nuclear factor-kappa B activity in GBM cell lines. Disulfiram/copper may trigger intrinsic apoptotic pathway via modulation of the Bcl2 family. Disulfiram/copper abolishes stem-like cell population in GBM cell lines. Conclusion: Our findings indicate that the cytotoxicity of DS/Cu and the enhancing effect of DS/Cu on the cytotoxicity of dFdC in GBM stem-like cells may be caused by induction of ROS and inhibition of both ALDH and the NFkB pathway. Both DS and dFdC can traverse the blood–brain barrier. Further study may lead them into GBM chemotherapy. PMID:23033007

Effects of total flavonoids of sea buckthorn ( Hippophae rhamnoides L.) on cytotoxicity of NK92-MI cells.

PubMed

Hou, Diandong; Wang, Decheng; Ma, Xiande; Chen, Wenna; Guo, Shengnan; Guan, Hongquan

2017-12-01

Sea buckthorn ( Hippophae rhamnoides L.) has multifarious medicinal properties including immunoregulatory effect. The total flavonoids of Hippophae rhamnoides L. (TFH) are the main active components isolated from berries of sea buckthorn. The aim of this study was to evaluate the effects of TFH on the cytotoxicity of NK92-MI cells and its possible mechanisms. NK92-MI cells were treated with TFH (2.5 or 5.0 mg/L) or phosphate-buffered saline (PBS) for 24 h, the cytotoxicity against K562 was detected by measuring the release of lactate dehydrogenase (LDH), expression levels of NCRs (NKp30, NKp44, NKp46) and NKG2D were detected by flow cytometry, and expression levels of perforin and granzyme B were detected by western blot. Cytokine Antibody Arrays with 80 cytokine proteins were used to profile the effect of TFH on cytokines. Western blot was adopted to detect the effects of TFH on STAT1, STAT4, and STAT5 signal pathway. Compared with the normal control group, TFH could significantly enhance NK92-MI cell cytotoxicity against K562 cells, upregulate expressions of NKp44, NKp46, perforin, and granzyme B. TFH could upregulate expressions of IL-1α, IL-2, IL-7, IL-15, CSF-2, CSF-3, MCP-1, MIG, IFN-γ, TNF-α, and TNF-β and downregulate expressions of IL-16, MIP-1β, CX3CL-1, and MIF. TFH could increase expressions of phospho-STAT1 and phospho-STAT5. The results suggest that TFH stimulated NK92-MI cells to activate and enhance cytotoxicity of NK92-MI cells.

3-bromopyruvate enhanced daunorubicin-induced cytotoxicity involved in monocarboxylate transporter 1 in breast cancer cells.

PubMed

Liu, Zhe; Sun, Yiming; Hong, Haiyu; Zhao, Surong; Zou, Xue; Ma, Renqiang; Jiang, Chenchen; Wang, Zhiwei; Li, Huabin; Liu, Hao

2015-01-01

Increasing evidence demonstrates that the hexokinase inhibitor 3-bromopyruvate (3-BrPA) induces the cell apoptotic death by inhibiting ATP generation in human cancer cells. Interestingly, some tumor cell lines are less sensitive to 3-BrPA-induced apoptosis than others. Moreover, the molecular mechanism of 3-BrPA-trigged apoptosis is unclear. In the present study, we examined the effects of 3-BrPA on the viability of the breast cancer cell lines MDA-MB-231 and MCF-7. We further investigated the potential roles of monocarboxylate transporter 1 (MCT1) in drug accumulation and efflux of breast cancer cells. Finally, we explored whether 3-BrPA enhanced daunorubicin (DNR)-induced cytotoxicity through regulation of MCT1 in breast cancer cells. MTT and colony formation assays were used to measure cell viability. Western blot analysis, flow cytometric analysis and fluorescent microscopy were used to determine the molecular mechanism of actions of MCT1 in different breast cancer cell lines. Whole-body bioluminescence imaging was used to investigate the effect of 3-BrPA in vivo. We found that 3-BrPA significantly inhibited cell growth and induced apoptosis in MCF-7 cell line, but not in MDA-MB-231 cells. Moreover, we observed that 3-BrPA efficiently enhanced DNR-induced cytotoxicity in MCF-7 cells by inhibiting the activity of ATP-dependent efflux pumps. We also found that MCT1 overexpression increased the efficacy of 3-BrPA in MDA-MB-231 cells. 3-BrPA markedly suppressed subcutaneous tumor growth in combination with DNR in nude mice implanted with MCF-7 cells. Lastly, our whole-body bioluminescence imaging data indicated that 3-BrPA promoted DNR accumulation in tumors. These findings collectively suggest that 3-BrPA enhanced DNR antitumor activity in breast cancer cells involved MCT-1, suggesting that inhibition of glycolysis could be an effective therapeutic approach for breast cancer treatment.

Unsaturated fatty acids lactose esters: cytotoxicity, permeability enhancement and antimicrobial activity.

PubMed

Lucarini, Simone; Fagioli, Laura; Campana, Raffaella; Cole, Hannah; Duranti, Andrea; Baffone, Wally; Vllasaliu, Driton; Casettari, Luca

2016-10-01

Sugar based surfactants conjugated with fatty acid chains are an emerging broad group of highly biocompatible and biodegradable compounds with established and potential future applications in the pharmaceutical, cosmetic and food industries. In this work, we investigated absorption enhancing and antimicrobial properties of disaccharide lactose, monoesterified with unsaturated fatty acids through an enzymatic synthetic approach. After chemical and cytotoxicity characterizations, their permeability enhancing activity was demonstrated using intestinal Caco-2 monolayers through transepithelial electrical resistance (TEER) and permeability studies. The synthesized compounds, namely lactose palmitoleate (URB1076) and lactose nervonate (URB1077), were shown to exhibit antimicrobial activity versus eight pathogenic species belonging to Gram-positive, Gram-negative microorganisms and fungi. Copyright © 2016 Elsevier B.V. All rights reserved.

Microvesicle- and exosome-mediated drug delivery enhances the cytotoxicity of Paclitaxel in autologous prostate cancer cells.

PubMed

Saari, Heikki; Lázaro-Ibáñez, Elisa; Viitala, Tapani; Vuorimaa-Laukkanen, Elina; Siljander, Pia; Yliperttula, Marjo

2015-12-28

Extracellular vesicles (EVs) are naturally occurring membrane particles that mediate intercellular communication by delivering molecular information between cells. In this study, we investigated the effectiveness of two different populations of EVs (microvesicle- and exosome-enriched) as carriers of Paclitaxel to autologous prostate cancer cells. EVs were isolated from LNCaP- and PC-3 prostate cancer cell cultures using differential centrifugation and characterized by electron microscopy, nanoparticle tracking analysis, and Western blot. The uptake of microvesicles and exosomes by the autologous prostate cancer cells was assessed by flow cytometry and confocal microscopy. The EVs were loaded with Paclitaxel and the effectiveness of EV-mediated drug delivery was assessed with viability assays. The distribution of EVs and EV-delivered Paclitaxel in cells was inspected by confocal microscopy. Our main finding was that the loading of Paclitaxel to autologous prostate cancer cell-derived EVs increased its cytotoxic effect. This capacity was independent of the EV population and the cell line tested. Although the EVs without the drug increased cancer cell viability, the net effect of enhanced cytotoxicity remained. Both EV populations delivered Paclitaxel to the recipient cells through endocytosis, leading to the release of the drug from within the cells. The removal of EV surface proteins did not affect exosomes, while the drug delivery mediated by microvesicles was partially inhibited. Cancer cell-derived EVs can be used as effective carriers of Paclitaxel to their parental cells, bringing the drug into the cells through an endocytic pathway and increasing its cytotoxicity. However, due to the increased cell viability, the use of cancer cell-derived EVs must be further investigated before any clinical applications can be designed. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

Curcumin stably interacts with DNA hairpin through minor groove binding and demonstrates enhanced cytotoxicity in combination with FdU nucleotides.

PubMed

Ghosh, Supratim; Mallick, Sumana; Das, Upasana; Verma, Ajay; Pal, Uttam; Chatterjee, Sabyasachi; Nandy, Abhishek; Saha, Krishna D; Maiti, Nakul Chandra; Baishya, Bikash; Suresh Kumar, G; Gmeiner, William H

2018-03-01

We report, based on biophysical studies and molecular mechanical calculations that curcumin binds DNA hairpin in the minor groove adjacent to the loop region forming a stable complex. UV-Vis and fluorescence spectroscopy indicated interaction of curcumin with DNA hairpin. In this novel binding motif, two ɣ H of curcumin heptadiene chain are closely positioned to the A 16 -H8 and A 17 -H8, while G 12 -H8 is located in the close proximity of curcumin α H. Molecular dynamics (MD) simulations suggest, the complex is stabilized by noncovalent forces including; π-π stacking, H-bonding and hydrophobic interactions. Nuclear magnetic resonance (NMR) spectroscopy in combination with molecular dynamics simulations indicated curcumin is bound in the minor groove, while circular dichroism (CD) spectra suggested minute enhancement in base stacking and a little change in DNA helicity, without significant conformational change of DNA hairpin structure. The DNA:curcumin complex formed with FdU nucleotides rather than Thymidine, demonstrated enhanced cytotoxicity towards oral cancer cells relative to the only FdU substituted hairpin. Fluorescence co-localization demonstrated stability of the complex in biologically relevant conditions, including its cellular uptake. Acridine orange/EtBr staining further confirmed the enhanced cytotoxic effects of the complex, suggesting apoptosis as mode of cell death. Thus, curcumin can be noncovalently complexed to small DNA hairpin for cellular delivery and the complex showed increased cytotoxicity in combination with FdU nucleotides, demonstrating its potential for advanced cancer therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Antimicrobial and cytotoxic effects of Mexican medicinal plants.

PubMed

Jacobo-Salcedo, Maria del Rosario; Alonso-Castro, Angel Josabad; Salazar-Olivo, Luis A; Carranza-Alvarez, Candy; González-Espíndola, Luis Angel; Domínguez, Fabiola; Maciel-Torres, Sandra Patricia; García-Lujan, Concepción; González-Martínez, Marisela del Rocio; Gómez-Sánchez, Maricela; Estrada-Castillón, Eduardo; Zapata-Bustos, Rocio; Medellin-Milán, Pedro; García-Carrancá, Alejandro

2011-12-01

The antimicrobial effects of the Mexican medicinal plants Guazuma ulmifolia, Justicia spicigera, Opuntia joconostle, O. leucotricha, Parkinsonia aculeata, Phoradendron longifolium, P. serotinum, Psittacanthus calyculatus, Tecoma stans and Teucrium cubense were tested against several human multi-drug resistant pathogens, including three Gram (+) and five Gram (-) bacterial species and three fungal species using the disk-diffusion assay. The cytotoxicity of plant extracts on human cancer cell lines and human normal non-cancerous cells was also evaluated using the MTT assay. Phoradendron longifolium, Teucrium cubense, Opuntia joconostle, Tecoma stans and Guazuma ulmifolia showed potent antimicrobial effects against at least one multidrug-resistant microorganism (inhibition zone > 15 mm). Only Justicia spicigera and Phoradendron serotinum extracts exerted active cytotoxic effects on human breast cancer cells (IC50 < or = 30 microg/mL). The results showed that Guazuma ulmifolia produced potent antimicrobial effects against Candida albicans and Acinetobacter lwoffii, whereas Justicia spicigera and Phoradendron serotinum exerted the highest toxic effects on MCF-7 and HeLa, respectively, which are human cancer cell lines. These three plant species may be important sources of antimicrobial and cytotoxic agents.

Antibody engineering of a cytotoxic monoclonal antibody 84 against human embryonic stem cells: Investigating the effects of multivalency on cytotoxicity.

PubMed

Klement, Maximilian; Zheng, Jiyun; Liu, Chengcheng; Tan, Heng-Liang; Wong, Victor Vai Tak; Choo, Andre Boon-Hwa; Lee, Dong-Yup; Ow, Dave Siak-Wei

2017-02-10

Antibody fragments have shown targeted specificity to their antigens, but only modest tissue retention times in vivo and in vitro. Multimerization has been used as a protein engineering tool to increase the number of binding units and thereby enhance the efficacy and retention time of antibody fragments. In this work, we explored the effects of valency using a series of self-assembling polypeptides based on the GCN4 leucine zipper multimerization domain fused to a single-chain variable fragment via an antibody upper hinge sequence. Four engineered antibody fragments with a valency from one to four antigen-binding units of a cytotoxic monoclonal antibody 84 against human embryonic stem cells (hESC) were constructed. We hypothesized that higher cytotoxicity would be observed for fragments with increased valency. Flow cytometry analysis revealed that the trimeric and tetrameric engineered antibody fragments resulted in the highest degree of cytotoxicity to the undifferentiated hESC, while the engineered antibody fragments were observed to have improved tissue penetration into cell clusters. Thus, a trade off was made for the trimeric versus tetrameric fragment due to improved tissue penetration. These results have direct implications for antibody-mediated removal of undifferentiated hESC during regenerative medicine and cell therapy. Copyright © 2016 The Author(s). Published by Elsevier B.V. All rights reserved.

Epidermal Cadm1 expression promotes autoimmune alopecia via enhanced T cell adhesion and cytotoxicity.

PubMed

Giangreco, Adam; Hoste, Esther; Takai, Yoshimi; Rosewell, Ian; Watt, Fiona M

2012-02-01

Autoimmune alopecia is characterized by an extensive epidermal T cell infiltrate that mediates hair follicle destruction. We have investigated the role of cell adhesion molecule 1 (Cadm1; Necl2) in this disease. Cadm1 is expressed by epidermal cells and mediates heterotypic adhesion to lymphocytes expressing class 1-restricted T cell-associated molecule (CRTAM). Using a murine autoimmune alopecia model, we observed an increase in early-activated cytotoxic (CD8-restricted, CRTAM-expressing) T cells, which preferentially associated with hair follicle keratinocytes expressing Cadm1. Coculture with Cadm1-transduced MHC-matched APCs stimulated alopecic lymph node cells to release IL-2 and IFN-γ. Overexpression of Cadm1 in cultured human keratinocytes did not promote cytokine secretion, but led to increased adhesion of alopecic cytotoxic T cells and enhanced T cell cytotoxicity in an MHC-independent manner. Epidermal overexpression of Cadm1 in transgenic mice led to increased autoimmune alopecia susceptibility relative to nontransgenic littermate controls. Our findings reveal that Cadm1 expression in the hair follicle plays a role in autoimmune alopecia.

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

PubMed Central

Bisetto, Sara; Newberg, Andrew; Doria, Cataldo; Levine, Mark; Monti, Daniel A.; Hoek, Jan B.

2016-01-01

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 pharmacological dose (5-20 mM) 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 (1 mM) 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

Engineering of dendrimer surfaces to enhance transepithelial transport and reduce cytotoxicity.

PubMed

Jevprasesphant, Rachaneekorn; Penny, Jeffrey; Attwood, David; McKeown, Neil B; D'Emanuele, Antony

2003-10-01

To evaluate the cytotoxicity, permeation, and transport mechanisms of PAMAM dendrimers and surface-modified cationic PAMAM dendrimers using monolayers of the human colon adenocarcinoma cell line, Caco-2. Cytotoxicity was determined using the MTT assay. The effect of dendrimers on monolayer integrity was determined from measurements of transepithelial electrical resistance (TEER) and [14C]mannitol apparent permeability coefficient (Papp). The Papp of dendrimers through monolayers was measured in both the apical (A)-to-basolateral (B) and B --> A directions at 4 degrees C and 37 degrees C and also in the presence and absence of ethylenediamine tetraacetic acid (EDTA) and colchicine. The cytotoxicity and permeation of dendrimers increased with both concentration and generation. The cytotoxicity of cationic dendrimers (G2, G3, G4) was greater than that of anionic dendrimers (G2.5, G3.5) but was reduced by conjugation with lauroyl chloride: the least cytotoxic conjugates were those with six attached lauroyl chains. At 37 degrees C the Papp of cationic dendrimers was higher than that of anionic dendrimers and, in general, increased with the number of attached lipid chains. Cationic dendrimers decreased TEER and significantly increased the Papp of mannitol. Modified dendrimers also reduced TEER and caused a more marked increase in the Papp of mannitol. The Papp values of dendrimers and modified dendrimers were higher in the presence of EDTA, lower in the presence of colchicine, and lower at 4 degrees C than at 37 degrees C. The properties of dendrimers may be significantly modified by surface engineering. Conjugation of cationic PAMAM dendrimers with lauroyl chloride decreased their cytotoxicity and increased their permeation through Caco-2 cell monolayers. Both PAMAM dendrimers and lauroyl-PAMAM dendrimer conjugates can cross epithelial monolayers by paracellular and transcellular pathways.

Phosphate-enhanced cytotoxicity of zinc oxide nanoparticles and agglomerates.

PubMed

Everett, W Neil; Chern, Christina; Sun, Dazhi; McMahon, Rebecca E; Zhang, Xi; Chen, Wei-Jung A; Hahn, Mariah S; Sue, H-J

2014-02-10

Zinc oxide (ZnO) nanoparticles (NPs) have been found to readily react with phosphate ions to form zinc phosphate (Zn3(PO4)2) crystallites. Because phosphates are ubiquitous in physiological fluids as well as waste water streams, it is important to examine the potential effects that the formation of Zn3(PO4)2 crystallites may have on cell viability. Thus, the cytotoxic response of NIH/3T3 fibroblast cells was assessed following 24h of exposure to ZnO NPs suspended in media with and without the standard phosphate salt supplement. Both particle dosage and size have been shown to impact the cytotoxic effects of ZnO NPs, so doses ranging from 5 to 50 μg/mL were examined and agglomerate size effects were investigated by using the bioinert amphiphilic polymer polyvinylpyrrolidone (PVP) to generate water-soluble ZnO ranging from individually dispersed 4 nm NPs up to micron-sized agglomerates. Cell metabolic activity measures indicated that the presence of phosphate in the suspension media can led to significantly reduced cell viability at all agglomerate sizes and at lower ZnO dosages. In addition, a reduction in cell viability was observed when agglomerate size was decreased, but only in the phosphate-containing media. These metabolic activity results were reflected in separate measures of cell death via the lactate dehydrogenase assay. Our results suggest that, while higher doses of water-soluble ZnO NPs are cytotoxic, the presence of phosphates in the surrounding fluid can lead to significantly elevated levels of cell death at lower ZnO NP doses. Moreover, the extent of this death can potentially be modulated or offset by tuning the agglomerate size. These findings underscore the importance of understanding how nanoscale materials can interact with the components of surrounding fluids so that potential adverse effects of such interactions can be controlled. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Analysis of Breast Cell-Lineage Response Differences to Taxol Using a Novel Co-Culture System

DTIC Science & Technology

2005-06-01

as the Hayflick limit [159], is thought to be a "mitotic clock" preventing cumulative cell damage from progressing to tumorigenesis [164-166] and...TERMS Breast cancer, co-culture, gene expression profiles, Taxol, transport mechanisms 16. SECURITY CLASSIFICATION OF: 17. LIMITATION 18. NUMBER 19a...proteins have been shown to bind and inactivate p53 and pRb respectively [25]. While the mortal cells have limited replicative potential in culture and

Piper betle leaf extract enhances the cytotoxicity effect of 5-fluorouracil in inhibiting the growth of HT29 and HCT116 colon cancer cells.

PubMed

Ng, Pek Leng; Rajab, Nor Fadilah; Then, Sue Mian; Mohd Yusof, Yasmin Anum; Wan Ngah, Wan Zurinah; Pin, Kar Yong; Looi, Mee Lee

2014-08-01

The combination effect of Piper betle (PB) and 5-fluorouracil (5-FU) in enhancing the cytotoxic potential of 5-FU in inhibiting the growth of colon cancer cells was investigated. HT29 and HCT116 cells were subjected to 5-FU or PB treatment. 5-FU and PB were then combined and their effects on both cell lines were observed after 24 h of treatment. PB-5-FU interaction was elucidated by isobologram analysis. Apoptosis features of the treated cells were revealed by annexin V/PI stain. High-performance liquid chromatography (HPLC) was performed to exclude any possible chemical interaction between the compounds. In the presence of PB extract, the cytotoxicity of 5-FU was observed at a lower dose (IC50 12.5 µmol/L) and a shorter time (24 h) in both cell lines. Both cell lines treated with 5-FU or PB alone induced a greater apoptosis effect compared with the combination treatment. Isobologram analysis indicated that PB and 5-FU interacted synergistically and antagonistically in inhibiting the growth of HT29 and HCT116 cells, respectively. In the presence of PB, a lower dosage of 5-FU is required to achieve the maximum drug effect in inhibiting the growth of HT29 cells. However, PB did not significantly reduce 5-FU dosage in HCT116 cells. Our result showed that this interaction may not solely contribute to the apoptosis pathway.

Piper betle leaf extract enhances the cytotoxicity effect of 5-fluorouracil in inhibiting the growth of HT29 and HCT116 colon cancer cells*

PubMed Central

Ng, Pek Leng; Rajab, Nor Fadilah; Then, Sue Mian; Mohd Yusof, Yasmin Anum; Wan Ngah, Wan Zurinah; Pin, Kar Yong; Looi, Mee Lee

2014-01-01

Objective: The combination effect of Piper betle (PB) and 5-fluorouracil (5-FU) in enhancing the cytotoxic potential of 5-FU in inhibiting the growth of colon cancer cells was investigated. Methods: HT29 and HCT116 cells were subjected to 5-FU or PB treatment. 5-FU and PB were then combined and their effects on both cell lines were observed after 24 h of treatment. PB-5-FU interaction was elucidated by isobologram analysis. Apoptosis features of the treated cells were revealed by annexin V/PI stain. High-performance liquid chromatography (HPLC) was performed to exclude any possible chemical interaction between the compounds. Results: In the presence of PB extract, the cytotoxicity of 5-FU was observed at a lower dose (IC50 12.5 μmol/L) and a shorter time (24 h) in both cell lines. Both cell lines treated with 5-FU or PB alone induced a greater apoptosis effect compared with the combination treatment. Isobologram analysis indicated that PB and 5-FU interacted synergistically and antagonistically in inhibiting the growth of HT29 and HCT116 cells, respectively. Conclusions: In the presence of PB, a lower dosage of 5-FU is required to achieve the maximum drug effect in inhibiting the growth of HT29 cells. However, PB did not significantly reduce 5-FU dosage in HCT116 cells. Our result showed that this interaction may not solely contribute to the apoptosis pathway. PMID:25091987

Cytotoxic Effects of Temozolomide and Radiation are Additive- and Schedule-Dependent

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chalmers, Anthony J., E-mail: a.j.chalmers@sussex.ac.u; Genome Damage and Stability Centre, University of Sussex, Falmer; Ruff, Elliot M.

2009-12-01

Purpose: Despite aggressive therapy comprising radical radiation and temozolomide (TMZ) chemotherapy, the prognosis for patients with glioblastoma multiforme (GBM) remains poor, particularly if tumors express O{sup 6}-methylguanine-DNA-methyltransferase (MGMT). The interactions between radiation and TMZ remain unclear and have important implications for scheduling and for developing strategies to improve outcomes. Methods and Materials: Factors determining the effects of combination therapy on clonogenic survival, cell-cycle checkpoint signaling and DNA repair were investigated in four human glioma cell lines (T98G, U373-MG, UVW, U87-MG). Results: Combining TMZ and radiation yielded additive cytotoxicity, but only when TMZ was delivered 72 h before radiation. Radiosensitization wasmore » not observed. TMZ induced G2/M cell-cycle arrest at 48-72 h, coincident with phosphorylation of Chk1 and Chk2. Additive G2/M arrest and Chk1/Chk2 phosphorylation was only observed when TMZ preceded radiation by 72 h. The ataxia-telangiectasia mutated (ATM) inhibitor KU-55933 increased radiation sensitivity and delayed repair of radiation-induced DNA breaks, but did not influence TMZ effects. The multiple kinase inhibitor caffeine enhanced the cytotoxicity of chemoradiation and exacerbated DNA damage. Conclusions: TMZ is not a radiosensitizing agent but yields additive cytotoxicity in combination with radiation. Our data indicate that TMZ treatment should commence at least 3 days before radiation to achieve maximum benefit. Activation of G2/M checkpoint signaling by TMZ and radiation has a cytoprotective effect that can be overcome by dual inhibition of ATM and ATR. More specific inhibition of checkpoint signaling will be required to increase treatment efficacy without exacerbating toxicity.« less

Enhancement of nitrosourea cytotoxicity by misonidazole in vitro: correlation with carbamoylating potential.

PubMed Central

Mulcahy, R. T.; Dembs, N. L.; Ublacker, G. A.

1984-01-01

We have investigated the relationships between nitrosourea structure and physicochemical properties and the ability of misonidazole (MISO) to potentiate nitrosourea cytotoxicity in an in vitro model system. EMT-6/Ro tumour cells were exposed in suspension to each of 9 different nitrosourea anti-tumour drugs under hypoxic and aerobic culture conditions. Additional cultures were similarly treated with nitrosoureas in the presence of 1.0 mM MISO. Seven of the 9 nitrosoureas did not demonstrate any selective toxicity toward aerobic or hypoxic cells. In contrast, chlorozotocin (CHLZ) was slightly more toxic toward hypoxic cells while Bis-OH CyNU more effectively killed aerobic cells. The addition of MISO to the drug treatment enhanced the effectiveness of all the nitrosoureas under hypoxic conditions, with the exception of CHLZ which was uninfluenced by MISO. The magnitude of the MISO dose enhancement factor (DEF, defined as the ratio of drug doses required to reduce cell survival to S = 10(-3) in 4 hours in the absence and presence of 1.0 mM MISO) for each combination was examined as a function of the relative carbamoylating or alkylating activity of the nitrosourea included in that combination. Such an analysis revealed a significant (P less than 0.05) positive correlation between relative carbamoylating potency and DEF. No significant (P greater than 0.20) relationship could be established for DEF and alkylating activity. PMID:6704305

Reovirus-Mediated Cytotoxicity and Enhancement of Innate Immune Responses Against Acute Myeloid Leukemia

PubMed Central

Hall, Kathryn; Scott, Karen J.; Rose, Ailsa; Desborough, Michael; Harrington, Kevin; Pandha, Hardev; Parrish, Christopher; Vile, Richard; Coffey, Matt; Bowen, David; Errington-Mais, Fiona

2012-01-01

Abstract Reovirus is a naturally occurring oncolytic virus that has shown preclinical efficacy in the treatment of a wide range of tumor types and has now reached phase III testing in clinical trials. The anti-cancer activity of reovirus has been attributed to both its direct oncolytic activity and the enhancement of anti-tumor immune responses. In this study, we have investigated the direct effect of reovirus on acute myeloid leukemia (AML) cells and its potential to enhance innate immune responses against AML, including the testing of primary samples from patients. Reovirus was found to replicate in and kill AML cell lines, and to reduce cell viability in primary AML samples. The pro-inflammatory cytokine interferon alpha (IFNα) and the chemokine (C-C motif) ligand 5 (known as RANTES [regulated upon activation, normal T-cell expressed, and secreted]) were also secreted from AML cells in response to virus treatment. In addition, reovirus-mediated activation of natural killer (NK) cells, within the context of peripheral blood mononuclear cells, stimulated their anti-leukemia response, with increased NK degranulation and IFNγ production and enhanced killing of AML targets. These data suggest that reovirus has the potential as both a direct cytotoxic and an immunotherapeutic agent for the treatment of AML. PMID:23515241

Histone Deacetylase Inhibitors Enhance Cytotoxicity Towards Breast Tumors While Preserving the Wound-Healing Function of Adipose-Derived Stem Cells.

PubMed

Koko, Kiavash R; Chang, Shaohua; Hagaman, Ashleigh L; Fromer, Marc W; Nolan, Ryan S; Gaughan, John P; Zhang, Ping; Carpenter, Jeffrey P; Brown, Spencer A; Matthews, Martha; Bird, Dorothy

2017-06-01

Paclitaxel improves the oncologic response of breast cancer resections; however, it may negatively affect the wound-healing potential of human adipose-derived stem cells (hASCs) for fat grafting and reconstructive surgery. Histone deacetylase inhibitors (HDACis) modify the epigenetic regulation of gene expression and stabilize microtubules similarly to paclitaxel, thus, creating a synergistic mechanism of cell cycle arrest. We aim to combine these drugs to enhance cytotoxicity towards breast cancer cells, while preserving the wound-healing function of hASCs for downstream reconstructive applications. Triple negative breast cancer cells (MBA-MB-231) and hASCs (institutional review board-approved clinical isolates) were treated with a standard therapeutic dose of paclitaxel (1.0 μM) or with low-dose paclitaxel (0.1 μM) combined with the HDACi suberoylanilide hydroxamic acid or trichostatin A. Cell viability, gene expression, apoptosis, and wound-healing/migration were measured via methylthiazol tetrazolium assay, quantitative real-time polymerase chain reaction, annexin V assay, and fibroblast scratch assay, respectively. Combined HDACi and low-dose paclitaxel therapy maintained cytotoxicity towards breast cancer cells and preserved adipose-derived stem cell viability. Histone deacetylase inhibitor demonstrated selective anti-inflammatory effects on adipose-derived stem cell gene expression and decreased expression of the proapoptotic gene FAS. Furthermore, HDACi therapy did not increase relative apoptosis within hASCs. A scratch assay demonstrated enhanced wound healing among injured fibroblasts indirectly co-cultured with HDACi-treated hASCs. Combining HDACi with low-dose paclitaxel improved cytotoxicity towards breast cancer cells and preserved hASC viability. Furthermore, enhanced wound healing was observed by improved migration in a fibroblast scratch assay. These results suggest that the addition of HDACi to taxane chemotherapy regimens may improve oncologic

Extracellular biosynthesis of gadolinium oxide (Gd2O3) nanoparticles, their biodistribution and bioconjugation with the chemically modified anticancer drug taxol

PubMed Central

Khan, Shadab Ali; Gambhir, Sanjay

2014-01-01

Summary As a part of our programme to develop nanobioconjugates for the treatment of cancer, we first synthesized extracellular, protein-capped, highly stable and well-dispersed gadolinium oxide (Gd2O3) nanoparticles by using thermophilic fungus Humicola sp. The biodistribution of the nanoparticles in rats was checked by radiolabelling with Tc-99m. Finally, these nanoparticles were bioconjugated with the chemically modified anticancer drug taxol with the aim of characterizing the role of this bioconjugate in the treatment of cancer. The biosynthesized Gd2O3 nanoparticles were characterized by UV–vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoemission spectroscopy (XPS). The Gd2O3–taxol bioconjugate was confirmed by UV–vis spectroscopy and fluorescence microscopy and was purified by using high performance liquid chromatography (HPLC). PMID:24778946

Effector CD8+ T cell IFN-γ production and cytotoxicity are enhanced by mild hyperthermia

PubMed Central

Mace, Thomas A.; Zhong, Lingwen; Kokolus, Kathleen M.; Repasky, Elizabeth A.

2012-01-01

Purpose Clinical trials combining hyperthermia with radiation and/or chemotherapy for cancer treatment have resulted in improved overall survival and control of local recurrences. The contribution of thermally enhanced anti-immune function in these effects is of considerable interest, but not understood; studies on the fundamental effects of elevated temperature on immune effector cells are needed. The goal of this study is to investigate the potential of mild hyperthermia to impact tumor antigen-specific (Ag) effector CD8+ T cell functions. Method Pmel-1 Ag-specific CD8+ T cells were exposed to mild hyperthermia and tested for changes in IFN-γ production and cytotoxicity. Additionally, overall plasma membrane organization and the phosphorylation of signaling proteins were also investigated following heat treatment. Results Exposing effector Pmel-1 specific CD8+ T cells to mild hyperthermia (39.5°C) resulted in significantly enhanced Ag-specific IFN-γ production and tumor target cell killing compared to that seen using lower temperatures (33 and 37°C). Further, inhibition of protein synthesis during hyperthermia did not reduce subsequent Ag-induced IFN-γ production by CD8+ T cells. Correlated with these effects, we observed a distinct clustering of GM1+ lipid microdomains at the plasma membrane and enhanced phosphorylation of LAT and PKCθ which may be related to an observed enhancement of Ag-specific effector CD8+ T cell IFN-γ gene transcription following mild hyperthermia. However, mitogen–mediated production of IFN-γ, which bypasses T cell receptor activation with antigen, was not enhanced. Conclusions Antigen-dependent effector T cell activity is enhanced following mild hyperthermia. These effects could potentially occur in patients being treated with thermal therapies. These data also provide support for the use of thermal therapy as an adjuvant for immunotherapies to improve CD8+ effector cell function. PMID:22235780

Role of heteromeric gap junctions in the cytotoxicity of cisplatin.

PubMed

Tong, Xuhui; Dong, Shuying; Yu, Meiling; Wang, Qin; Tao, Liang

2013-08-09

In several systems, the presence of gap junctions made of a single connexin has been shown to enhance the cytotoxicity of cisplatin. However, most gap junction channels in vivo appear to be heteromeric (composed of more than one connexin isoform). Here we explore in HeLa cells the cytotoxicity to cisplatin that is enhanced by heteromeric gap junctions composed of Cx26 and Cx32, which have been shown to be more selective among biological permeants than the corresponding homomeric channels. We found that survival and subsequent proliferation of cells exposed to cisplatin were substantially reduced when gap junctions were present than when there were no gap junctions. Functional inhibition of gap junctions by oleamide enhanced survival/proliferation, and enhancement of gap junctions by retinoic acid decreased survival/proliferation. These effects occurred only in high density cultures, and the treatments were without effect when there was no opportunity for gap junction formation. The presence of functional gap junctions enhanced apoptosis as reflected in markers of both early-stage and late-stage apoptosis. Furthermore, analysis of caspases 3, 8 and 9 showed that functional gap junctions specifically induced apoptosis by the mitochondrial pathway. These results demonstrate that heteromeric Cx26/Cx32 gap junctions increase the cytotoxicity of cisplatin by induction of apoptosis via the mitochondrial pathway. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

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. Copyright © 2016 Elsevier Inc. All rights reserved.

Antagonism of Taxol Cytotoxicity by Prolactin: Implication for Patient Resistance to Chemotherapy

DTIC Science & Technology

2008-03-01

Perspectives I. Introduction SINCE ITS DISCOVERY in the 1930s as a distinct pituitaryhormone that stimulates milk production in rabbits, prolactin...vitellogenin ERE sequence (GGTCAnnn TGACC), is located at the distal rPRL enhancer next to the 1d Pit-1 site (Fig. 1), enabling physical association between Pit...1 and ER via the AF-2 domain of ER (19). Complex formation between Pit-1 and ER involves coactivators/corepressors, with SRC-1 and GRIP1 stimulating

Effects of the ACTH(4-9) analogue, ORG 2766, on vincristine cytotoxicity in two human lymphoma cell lines, U937 and U715.

PubMed Central

Kiburg, B.; van de Loosdrecht, A. A.; Schweitzer, K. M.; Ossenkoppele, G. J.; Müller, L. J.; Heimans, J. J.; Huijgens, P. C.

1994-01-01

The use of cytotoxic drug vincristine (VCR) is limited by the occurrence of peripheral neuropathy. A neurotrophic ACTH(4-9) analogue, ORG 2766, is being studied for its protective effect. Possible modulatory effects of ORG 2766 on tumour cell growth and interference with the cytotoxic efficacy of VCR were studied in two human lymphoma cell lines, U937 and U715. The effects of ORG 2766 on cell growth and survival and on VCR-mediated cytotoxicity were investigated using two MTT-based assays to study direct cytotoxic effects and to assess residual growth after pretreatment. Treatment with ORG 2766 alone had no effect on cell growth and survival. Neither did this drug affect VCR cytotoxicity. However, after 96 h pretreatment with ORG 2766 and a culture period of 7 days, a reduction in residual growth and a potentiation of VCR-induced inhibition of growth capacity was observed in U715 cells, and to some extent also in U937 cells. It is concluded that ORG 2766 has no stimulatory effects on tumour growth and does not negatively interfere with VCR-mediated cytotoxicity. Rather it enhances the cytostatic effect of VCR. It is suggested that ORG 2766 can safely be used in clinical trials investigating the ability of ORG 2766 to counteract VCR-induced neurotoxicity. PMID:8123480

Celecoxib-Induced Cytotoxic Effect Is Potentiated by Inhibition of Autophagy in Human Urothelial Carcinoma Cells

PubMed Central

Ho, I-Lin; Chang, Hong-Chiang; Chuang, Yuan-Ting; Lin, Wei-Chou; Lee, Ping-Yi; Chang, Shih-Chen; Chiang, Chih-Kang; Pu, Yeong-Shiau; Chou, Chien-Tso; Hsu, Chen-Hsun; Liu, Shing-Hwa

2013-01-01

Celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, can elicit anti-tumor effects in various malignancies. Here, we sought to clarify the role of autophagy in celecoxib-induced cytotoxicity in human urothelial carcinoma (UC) cells. The results shows celecoxib induced cellular stress response such as endoplasmic reticulum (ER) stress, phosopho-SAPK/JNK, and phosopho-c-Jun as well as autophagosome formation in UC cells. Inhibition of autophagy by 3-methyladenine (3-MA), bafilomycin A1 or ATG7 knockdown potentiated celecoxib-induced apoptosis. Up-regulation of autophagy by rapamycin or GFP-LC3B-transfection alleviated celecoxib-induced cytotoxicity in UC cells. Taken together, the inhibition of autophagy enhances therapeutic efficacy of celecoxib in UC cells, suggesting a novel therapeutic strategy against UC. PMID:24349176

Overexpression of the Anthocyanidin Synthase Gene in Strawberry Enhances Antioxidant Capacity and Cytotoxic Effects on Human Hepatic Cancer Cells.

PubMed

Giampieri, Francesca; Gasparrini, Massimiliano; Forbes-Hernandez, Tamara Y; Mazzoni, Luca; Capocasa, Franco; Sabbadini, Silvia; Alvarez-Suarez, Josè M; Afrin, Sadia; Rosati, Carlo; Pandolfini, Tiziana; Molesini, Barbara; Sánchez-Sevilla, José F; Amaya, Iraida; Mezzetti, Bruno; Battino, Maurizio

2018-01-24

Food fortification through the increase and/or modulation of bioactive compounds has become a major goal for preventing several diseases, including cancer. Here, strawberry lines of cv. Calypso transformed with a construct containing an anthocyanidin synthase (ANS) gene were produced to study the effects on anthocyanin biosynthesis, metabolism, and transcriptome. Three strawberry ANS transgenic lines (ANS L5, ANS L15, and ANS L18) were analyzed for phytochemical composition and total antioxidant capacity (TAC), and their fruit extracts were assessed for cytotoxic effects on hepatocellular carcinoma. ANS L18 fruits had the highest levels of total phenolics and flavonoids, while those of ANS L15 had the highest anthocyanin concentration; TAC positively correlated with total polyphenol content. Fruit transcriptome was also specifically affected in the polyphenol biosynthesis and in other related metabolic pathways. Fruit extracts of all lines exerted cytotoxic effects in a dose/time-dependent manner, increasing cellular apoptosis and free radical levels and impairing mitochondrial functionality.

Gold-Containing Indoles as Anti-Cancer Agents that Potentiate the Cytotoxic Effects of Ionizing Radiation

PubMed Central

Craig, Sandra; Gao, Lei; Lee, Irene; Gray, Thomas; Berdis, Anthony J.

2012-01-01

This report describes the design and application of several distinct gold-containing indoles as anti-cancer agents. When used individually, all gold-bearing compounds display cytostatic effects against leukemia and adherent cancer cell lines. However, two gold-bearing indoles show unique behavior by increasing the cytotoxic effects of clinically relevant levels of ionizing radiation. Quantifying the amount of DNA damage demonstrates that each gold-indole enhances apoptosis by inhibiting DNA repair. Both Au(I)-indoles were tested for inhibitory effects against various cellular targets including thioredoxin reductase, a known target of several gold compounds, and various ATP-dependent kinases. While neither compound significantly inhibits the activity of thioreoxin reductase, both showed inhibitory effects against several kinases associated with cancer initiation and progression. The inhibition of these kinases provides a possible mechanism for the ability of these Au(I)-indoles potentiate the cytotoxic effects of ionizing radiation. Clinical applications of combining Au(I)-indoles with ionizing radiation are discussed as a new strategy to achieve chemosensitization of cancer cells. PMID:22289037

Anti-inflammatory, gastroprotective, and cytotoxic effects of Sideritis scardica extracts.

PubMed

Tadić, Vanja M; Jeremic, Ivica; Dobric, Silva; Isakovic, Aleksandra; Markovic, Ivanka; Trajkovic, Vladimir; Bojovic, Dragica; Arsic, Ivana

2012-03-01

Sideritis scardica Griseb. (ironwort, mountain tea), an endemic plant of the Balkan Peninsula, has been used in traditional medicine in the treatment of gastrointestinal complaints, inflammation, and rheumatic disorders. This study aimed to evaluate its gastroprotective and anti-inflammatory activities. Besides, continuously increasing interest in assessing the role of the plant active constituents preventing the risk of cancer was a reason to make a detailed examination of the investigated ethanol, diethyl ether, ethyl acetate, and N-butanol extracts regarding cytotoxicity. Oral administration of the investigated extracts caused a dose-dependent anti-inflammatory effect in a model of carrageenan-induced rat paw edema. Gastroprotective activity of the extracts was investigated using an ethanol-induced acute stress ulcer in rats. The cytotoxic activity of plant extracts was assessed on PBMC, B16, and HL-60 cells and compared to the cytotoxicity of phenolic compounds identified in extracts. Apoptotic and necrotic cell death were analyzed by double staining with fluoresceinisothiocyanate (FITC)-conjugated annexin V and PI. The developed HPLC method enabled qualitative fingerprint analysis of phenolic compounds in the investigated extracts. Compared to the effect of the positive control, the anti-inflammatory drug indomethacine (4 mg/kg), which produced a 50 % decrease in inflammation, diethyl ether and N-butanol extracts exhibited about the same effect in doses of 200 and 100 mg/kg (53.6 and 48.7 %; 48.4 and 49.9 %, respectively). All investigated extracts produced dose-dependent gastroprotective activity with the efficacy comparable to that of the reference drug ranitidine. The diethyl ether extract showed significant dose-dependent cytotoxicity on B16 cells and HL-60 cells, decreasing cell growth to 51.3 % and 77.5 % of control, respectively, when used at 100 µg/mL. It seems that phenolic compounds (apigenin, luteolin, and their corresponding glycosides) are

Interleukin-2 activation of cytotoxic cells in postmastectomy seroma.

PubMed

Gercel-Taylor, C; Hoffman, J P; Taylor, D D; Owens, K J; Eisenberg, B L

1996-02-15

Lymphocytes were isolated from breast seroma fluids and used to study the mechanism of activation of cytotoxic lymphocytes and possible role of immunological potentiation following surgery in breast cancer patients. Single or serial samples were obtained from patients who had undergone mastectomy or lumpectomy with axillary node dissection. Lymphocytes were activated with rIL-2 (interleukin-2) and their cytotoxic activity was studied against Daudi and K562 cells and against a breast tumor line (SKBr-3). All of the patients (21/21) responded to IL-2 stimulation by significant activation of cytotoxic activity. The unstimulated cytotoxic activity of these cells against NK targets was low with less than 10% specific release in cytotoxicity assays. In simultaneous experiments, autologous seroma fluid was included during activation of lymphocytes to study possible regulatory molecules that may be present. In 17/21 patients, the presence of their seroma fluid, during the activation period, enhanced or did not effect the cytotoxic potential of their lymphocytes; inhibition was observed when seroma fluids from 4/21 patients were included. Analysis of the cytotoxic population derived from combined IL-2 and seroma treatments indicates the presence of cells with increased expression of CD56, and CD2, as well as in some cases CD16 expression. Cytotoxic lymphocytes derived from IL-2 and seroma treatments appeared to be more effective killers. Modulation of CD2 expression with seroma alone appeared to result in the generation of this highly cytotoxic population. This study demonstrates the role of CD2 expression in the effectiveness of LAK cell killing and also potential benefit of an immunotherapeutic approach to the postoperative treatment of carcinoma of the breast.

A photosensitizer delivered by bispecific antibody redirected T lymphocytes enhances cytotoxicity against EpCAM-expressing carcinoma cells upon light irradiation.

PubMed

Blaudszun, André-René; Moldenhauer, Gerhard; Schneider, Marc; Philippi, Anja

2015-01-10

Recently conducted clinical trials have provided impressive evidence that chemotherapy resistant metastatic melanoma and several hematological malignancies can be cured using adoptive T cell therapy or T cell-recruiting bispecific antibodies. However, a significant fraction of patients did not benefit from these treatments. Here we have evaluated the feasibility of a novel combination therapy which aims to further enhance the killing potential of bispecific antibody-redirected T lymphocytes by using these cells as targeted delivery system for photosensitizing agents. For a first in vitro proof-of-concept study, ex vivo activated human donor T cells were loaded with a poly(styrene sulfonate) (PSS)-complex of the model photosensitizer 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin (mTHPP). In the absence of light and when loading with the water-soluble PSS/mTHPP-complex occurred at a tolerable concentration, viability and cytotoxic function of loaded T lymphocytes were not impaired. When "drug-enhanced" T cells were co-cultivated with EpCAM-expressing human carcinoma cells, mTHPP was transferred to target cells. Notably, in the presence of a bispecific antibody, which cross-links effector and target cells thereby inducing the cytolytic activity of cytotoxic T lymphocytes, significantly more photosensitizer was transferred. Consequently, upon irradiation of co-cultures, redirected drug-loaded T cells were more effective in killing A549 lung and SKOV-3 ovarian carcinoma cells than retargeted unloaded T lymphocytes. Particularly, the additive approach using redirected unloaded T cells in combination with appropriate amounts of separately applied PSS/mTHPP was less efficient as well. Thus, by loading T lymphocytes with a stimulus-sensitive anti-cancer drug, we were able to enhance the cytotoxic capacity of carrier cells. Photosensitizer boosted T cells could open new perspectives for adoptive T cell therapy as well as targeted photodynamic therapy. Copyright © 2014

Comparison of free amino acids, antioxidants, soluble phenolic acids, cytotoxicity and immunomodulation of fermented mung bean and soybean.

PubMed

Ali, Norlaily Mohd; Yeap, Swee-Keong; Yusof, Hamidah Mohd; Beh, Boon-Kee; Ho, Wan-Yong; Koh, Soo-Peng; Abdullah, Mohd Puad; Alitheen, Noorjahan Banu; Long, Kamariah

2016-03-30

Mung bean and soybean have been individually reported previously to have antioxidant, cytotoxic and immunomodulatory effects, while fermentation is a well-known process to enhance the bioactive compounds that contribute to higher antioxidant, cytotoxic and immunomodulation effects. In this study, the free amino acids profile, soluble phenolic acids content, antioxidants, cytotoxic and immunomodulatory effects of fermented and non-fermented mung bean and soybean were compared. Fermented mung bean was recorded to have the highest level of free amino acids, soluble phenolic acids (especially protocatechuic acid) and antioxidant activities among all the tested products. Both fermented mung bean and soybean possessed cytotoxicity activities against breast cancer MCF-7 cells by arresting the G0/G1 phase followed by apoptosis. Moreover, fermented mung bean and soybean also induced splenocyte proliferation and enhanced the levels of serum interleukin-2 and interferon-γ. Augmented amounts of free amino acids and phenolic acids content after fermentation enhanced the antioxidants, cytotoxicity and immunomodulation effects of mung bean and soybean. More specifically, fermented mung bean showed the best effects among all the tested products. This study revealed the potential of fermented mung bean and soybean as functional foods for maintenance of good health. © 2015 Society of Chemical Industry.

Low-intensity ultrasound adjuvant therapy: enhancement of doxorubicin-induced cytotoxicity and the acoustic mechanisms involved.

PubMed

Kondo, Takashi; Yoshida, Toru; Ogawa, Ryohei; Hassan, Mariame A; Furusawa, Yukihiro; Zhao, Qing-Li; Watanabe, Akihiko; Morii, Akihiro; Feril, Loreto B; Tachibana, Katsuro; Kitagawa, Hiroshi; Tabuchi, Yoshiaki; Takasaki, Ichiro; Shehata, Mohammad H; Kudo, Nobuki; Tsukada, Kazuhiro

2009-06-01

In this study, the effects of low-intensity pulsed ultrasound (LIU) as an adjuvant to doxorubicin (DOX) treatment was further investigated in comparison to hyperthermia as another widely used adjuvant. The effects were compared with respect to cell killing and apoptosis induction in U937 cells. Human primary liver cancer (PLC) cells were also used to evaluate the effects of the combinations. The use of an echo contrast agent was investigated for further enhancement of cytotoxicity. Finally, the acoustic mechanisms involved were investigated. The effects of different treatment regimens on cell viability were determined using the Trypan blue dye-exclusion test. Apoptosis induction was detected by flow cytometry using fluorescein isothiocyanate-annexin V and propidium iodide staining. The mechanistic study involved electron paramagnetic spin trapping for detecting free radical formation as an indicator of the occurrence of inertial cavitation and spectrophotometry for sucrose hydrolysis as an indicator for noncavitational effects. The combination treatments exerted synergistic effects on cytotoxicity depending on the acoustic conditions used. The use of LIU as an adjuvant to DOX treatment was shown to be superior to the use of hyperthermia as an adjuvant. Moreover, the combination seems to be promising for other cancer types provided that the acoustic conditions are properly selected with respect to drug concentration. The key ultrasound mechanism responsible for the synergism observed was shown to be the production of free radicals by inertial cavitation. Non-cavitational forces were also shown to contribute to the effect. This study is motivating to engage in in vivo research with various cancer types as a step toward clinical applicability and is emphasizing on the importance of developing therapeutic protocols for setting LIU parameters with respect to other therapeutic conditions.

Blockade of interleukin-6 signalling with siltuximab enhances melphalan cytotoxicity in preclinical models of multiple myeloma.

PubMed

Hunsucker, Sally A; Magarotto, Valeria; Kuhn, Deborah J; Kornblau, Steven M; Wang, Michael; Weber, Donna M; Thomas, Sheeba K; Shah, Jatin J; Voorhees, Peter M; Xie, Hong; Cornfeld, Mark; Nemeth, Jeffrey A; Orlowski, Robert Z

2011-03-01

Signalling through the interleukin (IL)-6 pathway induces proliferation and drug resistance of multiple myeloma cells. We therefore sought to determine whether the IL-6-neutralizing monoclonal antibody siltuximab, formerly CNTO 328, could enhance the activity of melphalan, and to examine some of the mechanisms underlying this interaction. Siltuximab increased the cytotoxicity of melphalan in KAS-6/1, INA-6, ANBL-6, and RPMI 8226 human myeloma cell lines (HMCLs) in an additive-to-synergistic manner, and sensitized resistant RPMI 8226.LR5 cells to melphalan. These anti-proliferative effects were accompanied by enhanced activation of drug-specific apoptosis in HMCLs grown in suspension, and in HMCLs co-cultured with a human-derived stromal cell line. Siltuximab with melphalan enhanced activation of caspase-8, caspase-9, and the downstream effector caspase-3 compared with either of the single agents. This increased induction of cell death occurred in association with enhanced Bak activation. Neutralization of IL-6 also suppressed signalling through the phosphoinositide 3-kinase/Akt pathway, as evidenced by decreased phosphorylation of Akt, p70 S6 kinase and 4E-BP1. Importantly, the siltuximab/melphalan regimen demonstrated enhanced anti-proliferative effects against primary plasma cells derived from patients with myeloma, monoclonal gammopathy of undetermined significance, and amyloidosis. These studies provide a rationale for translation of siltuximab into the clinic in combination with melphalan-based therapies. © 2011 Blackwell Publishing Ltd.

Bcl-2 inhibitors potentiate the cytotoxic effects of radiation in Bcl-2 overexpressing radioresistant tumor cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hara, Takamitsu; Omura-Minamisawa, Motoko; Chao Cheng

Purpose: Bcl-2, an inhibitor of apoptosis frequently shows elevated expression in human tumors, thus resulting in resistance to radiation therapy. Therefore, inhibiting Bcl-2 function may enhance the radiosensitivity of tumor cells. Tetrocarcin A (TC-A) and bcl-2 antisense oligonucleotides exhibit antitumor activity by inhibiting Bcl-2 function and transcription, respectively. We investigated whether these antitumor agents would enhance the cytotoxic effects of radiation in tumor cells overexpressing Bcl-2. Methods and materials: We used HeLa/bcl-2 cells, a stable Bcl-2-expressing cell line derived from wild-type HeLa (HeLa/wt) cells. Cells were incubated with TC-A and bcl-2 antisense oligonucleotides for 24 h after irradiation, and cellmore » viability was then determined. Apoptotic cells were quantified by flow cytometric assay. Results: The HeLa/bcl-2 cells were more resistant to radiation than HeLa/wt cells. At concentrations that are not inherently cytotoxic, both TC-A and bcl-2 antisense oligonucleotides increased the cytotoxic effects of radiation in HeLa/bcl-2 cells, but not in HeLa/wt cells. However, in HeLa/bcl-2 cells, additional treatment with TC-A in combination with radiation did not significantly increase apoptosis. Conclusions: The present results suggest that TC-A and bcl-2 antisense oligonucleotides reduce radioresistance of tumor cells overexpressing Bcl-2. Therefore, a combination of radiotherapy and Bcl-2 inhibitors may prove to be a useful therapeutic approach for treating tumors that overexpress Bcl-2.« less

Effects of polysaccharide peptide (PSP) from Coriolus versicolor on the pharmacokinetics of cyclophosphamide in the rat and cytotoxicity in HepG2 cells.

PubMed

Chan, Siu-Lung; Yeung, John H K

2006-05-01

Polysaccharide peptide (PSP), isolated from Coriolus versicolor COV-1, has been shown to restore the immunological effects against cyclophosphamide-induced immuno-suppression, although the mechanism(s) involved remain uncertain. This study investigated the PSP-cyclophosphamide interaction by studying the effects of PSP on the pharmacokinetic of cyclophosphamide in the rat and the effect of PSP on the cytotoxic effects of cyclophosphamide on a cancer cell line (HepG2 cells). In the pharmacokinetic studies in the rat, acute pre-treatment of PSP (4 micromol/kg/day, i.p.) decreased the clearance (CL) of cyclophosphamide by 31%, with a concomitant increase in the area under concentration-time curve (AUC) by 44%, and prolongation of the plasma half-life (T(1/2)) by 43%. Sub-chronic pre-treatment of PSP (2 micromol/kg/day, i.p., 3 days) decreased the CL of cyclophosphamide by 33%, with a concomitant increase in the AUC by 50%, and prolongation of the plasma T(1/2) by 34%. In cytotoxicity studies using HepG2 cells, non-toxic dose of PSP (1-10 microM) enhanced the cytotoxicity of cyclophosphamide. PSP at 10 microM further decreased HepG2 cell viability by 22% compared to when cyclophosphamide was present alone. In summary, PSP enhanced the cytotoxic effect of cyclophosphamide on a cancer cell line in vitro and altered the pharmacokinetics of cyclophosphamide in vivo in the rat. Both of these effects may be beneficial in the use of PSP as an adjunct to cyclophosphamide treatment.

Microbicidal and cytotoxic effects of functional water in vitro.

PubMed

Gomi, Kazuhiro; Makino, Tomohiko; Suzuki, Shinichi; Hasegawa, Masako; Maeda, Nobuko; Arai, Takashi

2010-10-01

Several kinds of functional water are used in the fields of food hygiene and medicine. The purpose of this study was to evaluate both the disinfection and cytotoxic effects of functional water in comparison with commonly used root canal irrigants such as sodium hypochlorite solution and hydrogen peroxide solution. Three kinds of functional water were examined: alkaline electrolysis water (AEW), strong acid electrolyzed water (SAEW), and hypochlorous acid water (HAW). The disinfection effect was studied using Enterococcus faecalis and Candida albicans with or without organic substance. Each kind of functional water was applied to samples, and the colony formation was evaluated. The cytotoxic effect was evaluated by mitogenic assay (MTT) and alkaline phosphatase (ALPase) activity in pulp cells. SAEW and HAW showed microbicidal effects in the presence of organic substance, with an effect almost similar to sodium hypochlorite solution. AEW did not show any microbicidal effect. SAEW, AEW, and HAW at 10- and 1,000-times dilution did not inhibit the MTT assay and ALPase activity. The cytotoxicity of SAEW and HAW against pulp cells was mild compared to that of sodium hypochlorite solution. Functional water like SAEW and HAW have a good microbicidal effect under existing organic substance and are also mild to pulp cells.

The p53-reactivating small-molecule RITA enhances cisplatin-induced cytotoxicity and apoptosis in head and neck cancer.

PubMed

Roh, Jong-Lyel; Ko, Jung Ho; Moon, Soo Jin; Ryu, Chang Hwan; Choi, Jun Young; Koch, Wayne M

2012-12-01

We evaluated whether the restoration of p53 function by the p53-reactivating small molecule RITA (reactivation of p53 and induction of tumor cell apoptosis enhances cisplatin-induced cytotoxicity and apoptosis in head-and-neck cancer (HNC). RITA induced prominent accumulation and reactivation of p53 in a wild-type TP53-bearing HNC cell line. RITA showed maximal growth suppression in tumor cells showing MDM2-dependent p53 degradation. RITA promoted apoptosis in association with upregulation of p21, BAX, and cleaved caspase-3; notably, the apoptotic response was blocked by pifithrin-α, demonstrating its p53 dependence. With increasing concentrations, RITA strongly induced apoptosis rather than G2-phase arrest. In combination therapy, RITA enhanced cisplatin-induced growth inhibition and apoptosis of HNC cells invitro and in vivo. Our data suggest that the restoration of p53 tumor-suppressive function by RITA enhances the cytotoxicity and apoptosis of cisplatin, an action that may offer an attractive strategy for treating HNC. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Heavy metal-induced cytotoxicity to cultured human epidermal keratinocytes and effects of antioxidants.

PubMed

Kappus, H; Reinhold, C

1994-04-01

Human epidermal keratinocytes which have been cultured were treated with the heavy metal ions of cadmium, mercury, copper and zinc. Cytotoxicity was measured either by protein estimation or by using the neutral red assay. Antioxidants were added in order to find out whether heavy metal-induced cytotoxicity is related to oxidative stress. All metals used showed considerable cytotoxic effects within 24 h in moderate concentrations. None of the antioxidants vitamin E (alpha-tocopherol), pyrogallol, propyl gallate, BHT or ebselen showed any protective or preventive effect. This indicates that oxidative stress may not be involved in the cytotoxicity induced by heavy metals in human epidermal keratinocytes. The cells used are, however, a valuable tool to study mechanisms of cytotoxicity.

Low-dose naltrexone suppresses ovarian cancer and exhibits enhanced inhibition in combination with cisplatin.

PubMed

Donahue, Renee N; McLaughlin, Patricia J; Zagon, Ian S

2011-07-01

Ovarian cancer is the leading cause of death from gynecological malignancies. Although initial therapeutic modalities are successful, 65% of these women relapse with only palliative treatments available thereafter. Endogenous opioids repress the proliferation of human ovarian cancer cells in vitro, and do so in a receptor-mediated manner. The present study examined whether modulation of opioid systems by the opioid antagonist naltrexone (NTX), alone or in combination with standard of care therapies (taxol/paclitaxel, cisplatin), alters human ovarian cancer cell proliferation in tissue culture and tumor progression in mice. Administration of NTX for six hours every two days, but not continuously, reduced DNA synthesis and cell replication from vehicle-treated controls in tissue culture. Moreover, brief exposure to NTX in combination with taxol or cisplatin had an enhanced anticancer action. Mice with established ovarian tumors and treated with a low dosage of NTX (LDN), which invokes a short period of opioid receptor blockade, repressed tumor progression in a non-toxic fashion by reducing DNA synthesis and angiogenesis but not altering cell survival. The combination of LDN with cisplatin, but not taxol, resulted in an additive inhibitory effect on tumorigenesis with enhanced depression of DNA synthesis and angiogenesis. LDN combined with cisplatin alleviated the toxicity (e.g. weight loss) associated with cisplatin. LDN treatment upregulated the expression of the opioid growth factor (OGF, chemical term ([Met(5)]-enkephalin) and its receptor, OGFr. Previous tissue culture studies have reported that OGF is the only opioid peptide with antiproliferative activity on ovarian cancer cells, with OGF action mediated by OGFr. Thus, the common denominator of intermittent opioid receptor blockade by short-term NTX or LDN on ovarian cancer proliferation and tumorigenesis recorded herein appears to be related to the OGF-OGFr axis. These preclinical data may offer a non

Beyond taxol: microtubule-based treatment of disease and injury of the nervous system

PubMed Central

Ahmad, Fridoon J.

2013-01-01

Contemporary research has revealed a great deal of information on the behaviours of microtubules that underlie critical events in the lives of neurons. Microtubules in the neuron undergo dynamic assembly and disassembly, bundling and splaying, severing, and rapid transport as well as integration with other cytoskeletal elements such as actin filaments. These various behaviours are regulated by signalling pathways that affect microtubule-related proteins such as molecular motor proteins and microtubule severing enzymes, as well as a variety of proteins that promote the assembly, stabilization and bundling of microtubules. In recent years, translational neuroscientists have earmarked microtubules as a promising target for therapy of injury and disease of the nervous system. Proof-of-principle has come mainly from studies using taxol and related drugs to pharmacologically stabilize microtubules in animal models of nerve injury and disease. However, concerns persist that the negative consequences of abnormal microtubule stabilization may outweigh the positive effects. Other potential approaches include microtubule-active drugs with somewhat different properties, but also expanding the therapeutic toolkit to include intervention at the level of microtubule regulatory proteins. PMID:23811322

Altered UV absorbance and cytotoxicity of chlorinated sunscreen agents.

PubMed

Sherwood, Vaughn F; Kennedy, Steven; Zhang, Hualin; Purser, Gordon H; Sheaff, Robert J

2012-12-01

Sunscreens are widely utilized due to the adverse effects of ultraviolet (UV) radiation on human health. The safety of their active ingredients as well as that of any modified versions generated during use is thus of concern. Chlorine is used as a chemical disinfectant in swimming pools. Its reactivity suggests sunscreen components might be chlorinated, altering their absorptive and/or cytotoxic properties. To test this hypothesis, the UV-filters oxybenzone, dioxybenzone, and sulisobenzone were reacted with chlorinating agents and their UV spectra analyzed. In all cases, a decrease in UV absorbance was observed. Given that chlorinated compounds can be cytotoxic, the effect of modified UV-filters on cell viability was examined. Chlorinated oxybenzone and dioxybenzone caused significantly more cell death than unchlorinated controls. In contrast, chlorination of sulisobenzone actually reduced cytotoxicity of the parent compound. Exposing a commercially available sunscreen product to chlorine also resulted in decreased UV absorbance, loss of UV protection, and enhanced cytotoxicity. These observations show chlorination of sunscreen active ingredients can dramatically decrease UV absorption and generate derivatives with altered biological properties.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tang, Xiao-han; Deng, Suo; Li, Meng

Highlights: Black-Right-Pointing-Pointer HB-EGF over-expression in A2780/Taxol, A2780/CDDP cells and the matched xenografts. Black-Right-Pointing-Pointer CRM197 induces enhanced apoptosis in A2780/Taxol and A2780/CDDP cells. Black-Right-Pointing-Pointer CRM197 arrests A2780/Taxol and A2780/CDDP cells at G0/G1 phase. Black-Right-Pointing-Pointer CRM197 suppressed the A2780/Taxol and A2780/CDDP growth of xenografts. -- Abstract: Heparin-binding epidermal growth factor-like growth factor (HB-EGF) is a promising target for ovarian cancer therapy. Cross-reacting material 197 (CRM197), a specific HB-EGF inhibitor, has been proven to represent possible chemotherapeutic agent for ovarian cancer. However, the effect of CRM197 on the resistant ovarian carcinoma cells has not been sufficiently elucidated. Here, we found that HB-EGF wasmore » over-expressed in a paclitaxel-resistant human ovarian carcinoma cell line (A2780/Taxol) and a cisplatin-resistant cell line (A2780/CDDP), as well as the xenograft mouse tissue samples with these cells. To investigate the possible significance of the HB-EGF over-expression in A2780/Taxol and A2780/CDDP cells, we inhibited HB-EGF expression by CRM197 to investigate the effect of CRM197 treatment on these cells. We observed that CRM197 significantly induced anti-proliferative activity in a dose-dependent manner with the cell-cycle arrest at the G0/G1 phase and enhanced apoptosis in A2780/Taxol and A2780/CDDP cells. The sensitive ovarian carcinoma parental cell line (A2780), A2780/Taxol and A2780/CDDP cells formed tumors in nude mice, and enhanced tumorigenicity was observed in drug-resistant tumors. Furthermore, we observed that CRM197 significantly suppressed the growth of drug-resistant ovarian cancer xenografts in vivo (p < 0.001). These results suggest that CRM197 as an HB-EGF-targeted agent has potent anti-tumor activity in paclitaxel- and cisplatin-resistant ovarian cancer which over-express HB-EGF.« less

Antigen delivery by α2-macroglobulin enhances the cytotoxic T lymphocyte response

PubMed Central

Bowers, Edith V.; Horvath, Jeffrey J.; Bond, Jennifer E.; Cianciolo, George J.; Pizzo, Salvatore V.

2009-01-01

α2M* targets antigens to APCs for rapid internalization, processing, and presentation. When used as an antigen-delivery vehicle, α2M* amplifies MHC class II presentation, as demonstrated by increased antibody titers. Recent evidence, however, suggests that α2M* encapsulation may also enhance antigen-specific CTL immunity. In this study, we demonstrate that α2M*-delivered antigen (OVA) enhances the production of specific in vitro and in vivo CTL responses. Murine splenocytes expressing a transgenic TCR specific for CTL peptide OVA257–264 (SIINFEKL) demonstrated up to 25-fold greater IFN-γ and IL-2 secretion when treated in vitro with α2M*-OVA compared with soluble OVA. The frequency of IFN-γ-producing cells was increased ∼15-fold, as measured by ELISPOT. Expansion of the OVA-specific CD8+ T cell population, as assayed by tetramer binding and [3H]thymidine incorporation, and OVA-specific cell-mediated cytotoxicity, as determined by a flow cytometric assay, were also enhanced significantly by α2M*-OVA. Furthermore, significant CTL responses were observed at antigen doses tenfold lower than those required with OVA alone. Finally, we also observed enhanced humoral and CTL responses by naïve mice following intradermal immunization with α2M*-OVA. These α2M*-OVA-immunized mice demonstrated increased protection against a s.c.-implanted, OVA-expressing tumor, as demonstrated by delayed tumor growth and prolonged animal survival. The observation that α2M*-mediated antigen delivery elicits specific CTL responses suggests the cross-presentation of antigen onto MHC class I. These results support α2M* as an effective antigen-delivery system that may be particularly useful for vaccines based on weakly immunogenic subunits or requiring dose sparing. PMID:19652028

Evaluation of the Cytotoxic Effects of Hyperthermia and 5-Fluorouracil Loaded Magnetic Nanoparticles on Human Colon Cancer Cell Line HT-29.

PubMed

Eynali, Samira; Khoei, Samideh; Khoei, Sepideh; Esmaelbeygi, Elaheh

2016-10-04

The purpose of this study was to evaluate the combined effects of heat and poly lactic-co-glycolic acid (PLGA) nanoparticles, as 5-fluorouracil carriers with/without iron oxide core, on the viability and proliferation capacity of human colon cancer cell line HT-29 in the spheroid model. HT-29 spheroid cells were treated with different concentrations of 5-FU or 5-FU loaded into both nanoparticles for 74 h. Hyperthermia was then performed at 43°C for 60 min. Finally, the effects of the mentioned treatments on cell viability and proliferation capacity were evaluated using the trypan blue dye exclusion test and colony formation assay, respectively. Our results showed that hyperthermia, in combination with 5-FU or PLGA nanoparticles as 5-FU carriers, significantly enhanced the cytotoxic effects as compared to the control group. Considering that nanoparticles could increase the intracellular concentration of drugs in cancer cells, the extent of cytotoxic effects following treatment with 5-FU loaded into both nanoparticles was significantly higher than that with free 5-FU. In addition, the presence of iron oxide cores in nanoparticles during hyperthermia enhanced the cytotoxic effects of hyperthermia compared with nanoparticles without iron oxide core. Based on this study, hyperthermia in combination with 5-FU-loaded PLGA nanoparticles with iron oxide core drastically reduced the proliferation capacity of HT-29 cells; therefore, it may be considered a new direction in the treatment of colon cancer.

Regulation of NK92-MI cell cytotoxicity by substance P.

PubMed

Fu, W X; Qin, B; Zhou, A P; Yu, Q Y; Huang, Q J; Liang, Z F

2011-08-01

The neuropeptide substance P (SP) can regulate a number of immunological functions in vitro and in vivo and may regulate natural killer (NK) cell activity. Here, we investigated whether SP has a role in regulating NK92-MI cell function in vitro, and how it influences NK cell activity. We found that SP dose dependently increased the cytotoxicity of NK92-MI cells and had a maximal effect at a concentration of 10(-12) and 10(-10) m. Furthermore, the expression of cytotoxic-associated molecules (perforin, granzyme) and activating receptor NKp46 [a member of natural cytotoxicity receptors (NCRs)] was observed to be upregulated by SP at optimal concentration, at which SP enhanced the cytotoxicity of NK92-MI cells. Neurokinin-1 receptor (NK-1R), a functional receptor of SP, was found on NK92-MI cells, and the observed effects of SP on NK92-MI cells could be more partially blocked by an NK-1R antagonist. Our data suggest that SP induces NK92-MI cell cytotoxicity by directly increasing the expression of cytotoxic granules and upregulates NK92-MI cell receptor-mediated functions indirectly. Thus, SP may regulate NK cell function mainly through NK-1R. © 2011 The Authors. Scandinavian Journal of Immunology © 2011 Blackwell Publishing Ltd.

Effects of retinoic acid-inducible gene-I-like receptors activations and ionizing radiation cotreatment on cytotoxicity against human non-small cell lung cancer in vitro.

PubMed

Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo

2018-04-01

Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis.

Effects of retinoic acid-inducible gene-I-like receptors activations and ionizing radiation cotreatment on cytotoxicity against human non-small cell lung cancer in vitro

PubMed Central

Yoshino, Hironori; Iwabuchi, Miyu; Kazama, Yuka; Furukawa, Maho; Kashiwakura, Ikuo

2018-01-01

Retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs) are pattern-recognition receptors that recognize pathogen-associated molecular patterns and induce antiviral immune responses. Recent studies have demonstrated that RLR activation induces antitumor immunity and cytotoxicity against different types of cancer, including lung cancer. However a previous report has demonstrated that ionizing radiation exerts a limited effect on RLR in human monocytic cell-derived macrophages, suggesting that RLR agonists may be used as effective immunostimulants during radiation therapy. However, it is unclear whether ionizing radiation affects the cytotoxicity of RLR agonists against cancer cells. Therefore, in the present study the effects of cotreatment with ionizing radiation and RLR agonists on cytotoxicity against human non-small cell lung cancer cells A549 and H1299 was investigated. Treatment with RLR agonist poly(I:C)/LyoVec™ [poly(I:C)] exerted cytotoxic effects against human non-small cell lung cancer. The cytotoxic effects of poly(I:C) were enhanced by cotreatment with ionizing radiation, and poly(I:C) pretreatment resulted in the radiosensitization of non-small cell lung cancer. Furthermore, cotreatment of A549 and H1299 cells with poly(I:C) and ionizing radiation effectively induced apoptosis in a caspase-dependent manner compared with treatment with poly(I:C) or ionizing radiation alone. These results indicate that RLR agonists and ionizing radiation cotreatment effectively exert cytotoxic effects against human non-small cell lung cancer through caspase-mediated apoptosis. PMID:29541243

The vitamin C:vitamin K3 system - enhancers and inhibitors of the anticancer effect.

PubMed

Lamson, Davis W; Gu, Yu-Huan; Plaza, Steven M; Brignall, Matthew S; Brinton, Cathy A; Sadlon, Angela E

2010-12-01

The oxidizing anticancer system of vitamin C and vitamin K₃ (VC:VK₃, producing hydrogen peroxide via superoxide) was combined individually with melatonin, curcumin, quercetin, or cholecalciferol (VD₃) to determine interactions. Substrates were LNCaP and PC-3 prostate cancer cell lines. Three of the tested antioxidants displayed differences in cell line cytotoxicity. Melatonin combined with VC:VK₃ quenched the oxidizing effect, while VC:VK₃ applied 24 hours after melatonin showed no quenching. With increasing curcumin concentrations, an apparent combined effect of VC:VK₃ and curcumin occurred in LNCaP cells, but not PC-3 cells. Quercetin alone was cytotoxic on both cell lines, but demonstrated an additional 50-percent cytotoxicity on PC-3 cells when combined with VC:VK₃. VD₃ was effective against both cell lines, with more effect on PC-3. This effect was negated on LNCaP cells with the addition of VC:VK₃. In conclusion, a natural antioxidant can enhance or decrease the cytotoxicity of an oxidizing anticancer system in vitro, but generalizations about antioxidants cannot be made.

Silver ion-enhanced particle-specific cytotoxicity of silver nanoparticles and effect on the production of extracellular secretions of Phanerochaete chrysosporium.

PubMed

Huang, Zhenzhen; Xu, Piao; Chen, Guiqiu; Zeng, Guangming; Chen, Anwei; Song, Zhongxian; He, Kai; Yuan, Lei; Li, Hui; Hu, Liang

2018-04-01

This study investigated the influence of silver ions (Ag + ) on the cytotoxicity of silver nanoparticles (AgNPs) in Phanerochaete chrysosporium and noted the degree of extracellular secretions in response to the toxicant's stress. Oxalate production was elicited with moderate concentrations of 2,4-dichlorophenol (2,4-DCP) and AgNPs reaching a plateau at 10 mg/L and 10 μM, respectively. Increased oxalate accumulation was accompanied by higher activities of manganese peroxidase (MnP) and lignin peroxidase (LiP). However, the secretion of oxalate, MnP and LiP was significantly inhibited owing to Ag + incorporation into AgNP solution. Production of extracellular polymeric substances (EPS) significantly elevated with an increase in 2,4-DCP concentrations; however, after 24 h of exposure to 100 mg/L 2,4-DCP, an obvious decrease in EPS occurred, indicating that part of EPS could be consumed as carbon and energy sources to ameliorate biological tolerance to toxic stress. Furthermore, AgNP-induced "particle-specific" cytotoxicity was substantially enhanced with additional Ag + as evidenced by its significant negative impact on cellular growth, plasma membrane integrity, and morphological preservation compared with AgNPs at equal Ag concentration. Copyright © 2017 Elsevier Ltd. All rights reserved.

Astaxanthin down-regulates Rad51 expression via inactivation of AKT kinase to enhance mitomycin C-induced cytotoxicity in human non-small cell lung cancer cells.

PubMed

Ko, Jen-Chung; Chen, Jyh-Cheng; Wang, Tai-Jing; Zheng, Hao-Yu; Chen, Wen-Ching; Chang, Po-Yuan; Lin, Yun-Wei

2016-04-01

Astaxanthin has been demonstrated to exhibit a wide range of beneficial effects, including anti-inflammatory and anti-cancer properties. However, the molecular mechanism of astaxanthin-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells has not been identified. Rad51 plays a central role in homologous recombination, and studies show that chemo-resistant carcinomas exhibit high levels of Rad51 expression. In this study, astaxanthin treatment inhibited cell viability and proliferation of two NSCLC cells, A549 and H1703. Astaxanthin treatment (2.5-20 μM) decreased Rad51 expression and phospho-AKT(Ser473) protein level in a time and dose-dependent manner. Furthermore, expression of constitutively active AKT (AKT-CA) vector rescued the decreased Rad51 mRNA and protein levels in astaxanthin-treated NSCLC cells. Combined treatment with phosphatidylinositol 3-kinase (PI3K) inhibitors (LY294002 or wortmannin) further decreased the Rad51 expression in astaxanthin-exposed A549 and H1703 cells. Knockdown of Rad51 expression by transfection with si-Rad51 RNA or cotreatment with LY294002 further enhanced the cytotoxicity and cell growth inhibition of astaxanthin. Additionally, mitomycin C (MMC) as an anti-tumor antibiotic is widely used in clinical NSCLC chemotherapy. Combination of MMC and astaxanthin synergistically resulted in cytotoxicity and cell growth inhibition in NSCLC cells, accompanied with reduced phospho-AKT(Ser473) level and Rad51 expression. Overexpression of AKT-CA or Flag-tagged Rad51 reversed the astaxanthin and MMC-induced synergistic cytotoxicity. In contrast, pretreatment with LY294002 further decreased the cell viability in astaxanthin and MMC co-treated cells. In conclusion, astaxanthin enhances MMC-induced cytotoxicity by decreasing Rad51 expression and AKT activation. These findings may provide rationale to combine astaxanthin with MMC for the treatment of NSCLC. Copyright © 2016 Elsevier Inc. All rights reserved.

Metformin, at concentrations corresponding to the treatment of diabetes, potentiates the cytotoxic effects of carboplatin in cultures of ovarian cancer cells.

PubMed

Erices, Rafaela; Bravo, Maria Loreto; Gonzalez, Pamela; Oliva, Bárbara; Racordon, Dusan; Garrido, Marcelo; Ibañez, Carolina; Kato, Sumie; Brañes, Jorge; Pizarro, Javier; Barriga, Maria Isabel; Barra, Alejandro; Bravo, Erasmo; Alonso, Catalina; Bustamente, Eva; Cuello, Mauricio A; Owen, Gareth I

2013-12-01

The use of the type 2 diabetics drug metformin has been correlated with enhanced progression-free survival in ovarian cancer. The literature has speculated that this enhancement is due to the high concentration of metformin directly causing cancer cell death. However, this explanation does not fit with clinical data reporting that the women exposed to constant micromolar concentrations of metformin, as present in the treatment of diabetes, respond better to chemotherapy. Herein, our aim was to examine whether micromolar concentrations of metformin alone could bring about cancer cell death and whether micromolar metformin could increase the cytotoxic effect of commonly used chemotherapies in A2780 and SKOV3 cell lines and primary cultured cancer cells isolated from the peritoneal fluid of patients with advanced ovarian cancer. Our results in cell lines demonstrate that no significant loss of viability or change in cell cycle was observed with micromolar metformin alone; however, we observed cytotoxicity with micromolar metformin in combination with chemotherapy at concentrations where the chemotherapy alone produced no loss in viability. We demonstrate that previous exposure and maintenance of metformin in conjunction with carboplatin produces a synergistic enhancement in cytotoxicity of A2780 and SKOV3 cells (55% and 43%, respectively). Furthermore, in 5 (44%) of the 11 ovarian cancer primary cultures, micromolar metformin improved the cytotoxic response to carboplatin but not paclitaxel or doxorubicin. In conclusion, we present data that support the need for a clinical study to evaluate the adjuvant maintenance or prescription of currently approved doses of metformin during the chemotherapeutic treatment of ovarian cancer.

Inhibition of the MUC1-C oncoprotein is synergistic with cytotoxic agents in the treatment of breast cancer cells

PubMed Central

Uchida, Yasumitsu; Raina, Deepak; Kharbanda, Surender; Kufe, Donald

2013-01-01

Mucin 1 (MUC1) is a heterodimeric glycoprotein that is aberrantly overexpressed in most human breast cancers. The oncogenic MUC1-C subunit promotes survival and blocks the apoptotic response to genotoxic anticancer agents. In the present studies, human MCF-7 and ZR-75-1 breast cancer cells were treated with the MUC1-C inhibitor, GO-203, a cell-penetrating peptide that blocks MUC1-C homodimerization and thereby its oncogenic function. Treatment with GO-203 was found to promote the apoptotic response of MCF-7 and ZR-75-1 cells to the therapeutic drugs taxol and doxorubicin (DOX). This effect was (1) attenuated by a pan-caspase inhibitor, and (2) mediated, at least in part, by activation of the effector caspase-7 and cleavage of the downstream substrate PARP. Further analysis of the interaction between GO-203 and taxol using isobolograms, which evaluate the nature of the interaction of two drugs, demonstrated that the combination is highly synergistic. These results were supported by combination index (CI) analysis with values of less than 1. GO-203 was also highly synergistic with DOX in studies of both MCF-7 and ZR-75-1 breast cancer cells. These findings indicate that blocking MUC1-C function could be effective in combination with taxol and DOX for the treatment of breast cancer. PMID:23114713

Poly-L-arginine: Enhancing Cytotoxicity and Cellular Uptake of Doxorubicin and Necrotic Cell Death.

PubMed

Movafegh, Bahareh; Jalal, Razieh; Mohammadi, Zobeideh; Aldaghi, Seyyede Araste

2018-04-11

Cell resistance to doxorubicin and its toxicity to healthy tissue reduce its efficiency. The use of cell penetrating peptides as drug delivery system along with doxorubicin is a strategy to reduce its side effects. In this study, the influence of poly-L-arginine on doxorubicin cytotoxicity, its cellular uptake and doxorubicin-induced apoptosis on human prostate cancer DU145 cells are assessed. The cytotoxicity of doxorubicin and poly-L-arginine, alone and in combination, in DU145 cells was evaluated at different exposure times using MTT assay. The influence of poly-L-arginine on doxorubicin delivery into cells was evaluated by fluorescence microscopy and ultraviolet spectroscopy. DAPI and ethidium bromide-acridine orange stainings, flow cytometry using annexin V/propidium iodide, western blot analysis with anti-p21 antibody and caspase-3 activity were used to examine the influence of poly-L-arginine on doxorubicin-induced cell death. Poly-L-arginine had no cytotoxicity at low concentrations and short exposure times. Poly-L-arginine increased the cytotoxic effect of doxorubicin in DU145 cells in a time-dependent manner. But no significant reduction was found in HFF cell viability. Poly-L-arginine seems to facilitate doxorubicin uptake and increase its intracellular concentration. 24 h combined treatment of cells with doxorubicin (0.5 μM) and poly-L-arginine (1 μg ml-1) caused a small increase in doxorubicin-induced apoptosis and significant elevated necrosis in DU145 cells as compared to each agent alone. Conlusion: Our results indicate that poly-L-arginine at lowest and highest concentrations act as proliferation-inducing and antiproliferative agents, respectively. Between these concentrations, poly-L-arginine increases the cellular uptake of doxorubicin and its cytotoxicity through induction of necrosis. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Gingerol Synergizes the Cytotoxic Effects of Doxorubicin against Liver Cancer Cells and Protects from Its Vascular Toxicity.

PubMed

Al-Abbasi, Fahad A; Alghamdi, Eman A; Baghdadi, Mohammed A; Alamoudi, Abdulmohsin J; El-Halawany, Ali M; El-Bassossy, Hany M; Aseeri, Ali H; Al-Abd, Ahmed M

2016-07-08

Hydroxyphenylalkanes and diarylheptanoids possess potential therapeutic value in different pathophysiological conditions, such as malignancy. In the current study, naturally isolated hydroxyphenylalkane and diarylheptanoid compounds were investigated for potential chemo-modulatory effects in addition to potential vascular protective roles with doxorubicin. Diarylheptanoids showed stronger antioxidant effects, in comparison to hydroxyphenylalkanes, as demonstrated by DPPH assay and amelioration of CCl₄-induced disturbed intracellular GSH/GSSG balance. Shogaol and 4'-methoxygingerol showed considerable cytotoxic effects against HCT116, HeLa, HepG2 and MCF7 cells, with IC50 values ranging from 3.1 to 19.4 µM. Gingerol significantly enhanced the cytotoxic profile of doxorubicin against HepG₂ and Huh7, cells decreasing its IC50s by 10- and 4-fold, respectively. Cell cycle distribution was studied using DNA cytometry. Doxorubicin alone induced cell accumulation at S-phase and G₂/M-phase, while in combination with gingerol it significantly induced cell cycle arrest at the G₂/M-phase. Additionally, the vascular protective effect of gingerol against doxorubicin (10 µM) was examined on isolated aortic rings. Co-incubation with 6-gingerol (30 µM) completely blocked the exaggerated vasoconstriction and impaired vascular relaxation induced by doxorubicin. In conclusion, despite its relatively weak antioxidant properties, gingerol protected from DOX-induced vascular damage, apparently not through a ROS scavenging mechanism. Besides, gingerol synergized the cytotoxic effects of DOX against liver cancer cells without influencing the cellular pharmacokinetics.

A semi high-throughput method for screening small bispecific antibodies with high cytotoxicity.

PubMed

Sugiyama, Aruto; Umetsu, Mitsuo; Nakazawa, Hikaru; Niide, Teppei; Onodera, Tomoko; Hosokawa, Katsuhiro; Hattori, Shuhei; Asano, Ryutaro; Kumagai, Izumi

2017-06-06

Small bispecific antibodies that induce T-cell-mediated cytotoxicity have the potential to damage late-stage tumor masses to a clinically relevant degree, but their cytotoxicity is critically dependent on their structural and functional properties. Here, we constructed an optimized procedure for identifying highly cytotoxic antibodies from a variety of the T-cell-recruiting antibodies engineered from a series of antibodies against cancer antigens of epidermal growth factor receptor family and T-cell receptors. By developing and applying a set of rapid operations for expression vector construction and protein preparation, we screened the cytotoxicity of 104 small antibodies with diabody format and identified some with 10 3 -times higher cytotoxicity than that of previously reported active diabody. The results demonstrate that cytotoxicity is enhanced by synergistic effects between the target, epitope, binding affinity, and the order of heavy-chain and light-chain variable domains. We demonstrate the importance of screening to determine the critical rules for highly cytotoxic antibodies.

Certain (-)-epigallocatechin-3-gallate (EGCG) auto-oxidation products (EAOPs) retain the cytotoxic activities of EGCG.

PubMed

Wei, Yaqing; Chen, Pingping; Ling, Tiejun; Wang, Yijun; Dong, Ruixia; Zhang, Chen; Zhang, Longjie; Han, Manman; Wang, Dongxu; Wan, Xiaochun; Zhang, Jinsong

2016-08-01

(-)-Epigallocatechin-3-gallate (EGCG) from green tea has anti-cancer effect. The cytotoxic actions of EGCG are associated with its auto-oxidation, leading to the production of hydrogen peroxide and formation of numerous EGCG auto-oxidation products (EAOPs), the structures and bioactivities of them remain largely unclear. In the present study, we compared several fundamental properties of EGCG and EAOPs, which were prepared using 5mg/mL EGCG dissolved in 200mM phosphate buffered saline (pH 8.0 at 37°C) and normal oxygen partial pressure for different periods of time. Despite the complete disappearance of EGCG after the 4-h auto-oxidation, 4-h EAOPs gained an enhanced capacity to deplete cysteine thiol groups, and retained the cytotoxic effects of EGCG as well as the capacity to produce hydrogen peroxide and inhibit thioredoxin reductase, a putative target for cancer prevention and treatment. The results indicate that certain EAOPs possess equivalent cytotoxic activities to EGCG, while exhibiting simultaneously enhanced capacity for cysteine depletion. These results imply that EGCG and EAOPs formed extracellularly function in concert to exhibit cytotoxic effects, which previously have been ascribed to EGCG alone. Copyright © 2016 Elsevier Ltd. All rights reserved.

Inhibition of ERK activity enhances the cytotoxic effect of peroxisome proliferator-activated receptor γ (PPARγ) agonists in HeLa cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Ha Kyun; Kim, Dae Seong; Chae, Jung Jun

In this study, we examined whether the peroxisome proliferator-activated receptor γ (PPARγ) agonists, ciglitazone (CGZ) and troglitazone (TGZ), induce cell death in human cervical cancer HeLa cells. The cells were treated with a range of CGZ or TGZ doses for 24 or 48 h. Low concentrations of CGZ (≤10 μM) or TGZ (≤20 μM) had no effect on cell viability whereas higher doses induced cell death in a time- and dose-dependent manner as evidenced by the detection of activated caspase-3 and PARP cleavage. Treatment with the PPARγ antagonist GW9662 followed by PPARγ agonists did not increase CGZ- or TGZ-induced cell death, indicating thatmore » PPARγ agonists induced HeLa cell death independently of PPARγ. Moreover, ERK1/2 activation was observed at a CGZ concentration of 25 μM and a TGZ concentration of 35 μM, both of which induced cell death. To elucidate the role of ERK1/2 activated by the two PPARγ agonists, the effect of U0126, an inhibitor of ERK1/2, on PPARγ-agonist-induced cell death was examined. Treatment with 10 or 20 μM U0126 followed by CGZ or TGZ induced the down-regulation of ERK1/2 activity and a decrease in Bcl-2 expression accompanied by the collapse of mitochondrial membrane potential, which in turn significantly enhanced CGZ- or TGZ-induced apoptotic cell death. Our results suggest that PPARγ agonists are capable of inducing apoptotic cell death in HeLa cells independently of PPARγ and that inhibition of ERK1/2 activity offers a strategy to enhance the cytotoxicity of PPARγ agonists in the treatment of cervical cancer. - Highlights: • The PPARγ agonists CGZ and TGZ induce apoptotic cell death in HeLa cells. • CGZ or TGZ induces apoptotic cell death independently of PPARγ in HeLa cells. • Inhibition of ERK1/2 enhances CGZ- or TGZ-induced cell death via the collapse of MMP.« less

Cytotoxicity of modified glass ionomer cement on odontoblast cells.

PubMed

Chen, Song; Mestres, Gemma; Lan, Weihua; Xia, Wei; Engqvist, Håkan

2016-07-01

Recently a modified glass ionomer cement (GIC) with enhanced bioactivity due to the incorporation of wollastonite or mineral trioxide aggregate (MTA) has been reported. The aim of this study was to evaluate the cytotoxic effect of the modified GIC on odontoblast-like cells. The cytotoxicity of a conventional GIC, wollastonite modified GIC (W-mGIC), MTA modified GIC (M-mGIC) and MTA cement has been evaluated using cement extracts, a culture media modified by the cement. Ion concentration and pH of each material in the culture media were measured and correlated to the results of the cytotoxicity study. Among the four groups, conventional GIC showed the most cytotoxicity effect, followed by W-mGIC and M-mGIC. MTA showed the least toxic effect. GIC showed the lowest pH (6.36) while MTA showed the highest (8.62). In terms of ion concentration, MTA showed the largest Ca(2+) concentration (467.3 mg/L) while GIC showed the highest concentration of Si(4+) (19.9 mg/L), Al(3+) (7.2 mg/L) and Sr(2+) (100.3 mg/L). Concentration of F(-) was under the detection limit (0.02 mg/L) for all samples. However the concentrations of these ions are considered too low to be toxic. Our study showed that the cytotoxicity of conventional GIC can be moderated by incorporating calcium silicate based ceramics. The modified GIC might be promising as novel dental restorative cements.

Carnosine's Effect on Amyloid Fibril Formation and Induced Cytotoxicity of Lysozyme

PubMed Central

Wu, Josephine W.; Liu, Kuan-Nan; How, Su-Chun; Chen, Wei-An; Lai, Chia-Min; Liu, Hwai-Shen; Hu, Chaur-Jong; Wang, Steven S. -S.

2013-01-01

Carnosine, a common dipeptide in mammals, has previously been shown to dissemble alpha-crystallin amyloid fibrils. To date, the dipeptide's anti-fibrillogensis effect has not been thoroughly characterized in other proteins. For a more complete understanding of carnosine's mechanism of action in amyloid fibril inhibition, we have investigated the effect of the dipeptide on lysozyme fibril formation and induced cytotoxicity in human neuroblastoma SH-SY5Y cells. Our study demonstrates a positive correlation between the concentration and inhibitory effect of carnosine against lysozyme fibril formation. Molecular docking results show carnosine's mechanism of fibrillogenesis inhibition may be initiated by binding with the aggregation-prone region of the protein. The dipeptide attenuates the amyloid fibril-induced cytotoxicity of human neuronal cells by reducing both apoptotic and necrotic cell deaths. Our study provides solid support for carnosine's amyloid fibril inhibitory property and its effect against fibril-induced cytotoxicity in SH-SY5Y cells. The additional insights gained herein may pave way to the discovery of other small molecules that may exert similar effects against amyloid fibril formation and its associated neurodegenerative diseases. PMID:24349167

Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

PubMed

Cho, Fu-Nan; Chang, Tsung-Hsien; Shu, Chih-Wen; Ko, Ming-Chin; Liao, Shuen-Kuei; Wu, Kang-Hsi; Yu, Ming-Sun; Lin, Shyh-Jer; Hong, Ying-Chung; Chen, Chien-Hsun; Hung, Chien-Hui; Chang, Yu-Hsiang

2014-01-01

Natural killer (NK) cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs), which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL) cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

Protective Effects of Liposomal N-Acetylcysteine against Paraquat-Induced Cytotoxicity and Gene Expression

PubMed Central

Mitsopoulos, Panagiotis; Suntres, Zacharias E.

2011-01-01

Paraquat (PQ) is a herbicide that preferentially accumulates in the lung and exerts its cytotoxicity via the generation of reactive oxygen species (ROS). There is no specific treatment for paraquat poisoning. Attempts have been made to increase the antioxidant status in the lung using antioxidants (e.g., superoxide dismutase, vitamin E, N-acetylcysteine) but the outcome from such treatments is limited. Encapsulation of antioxidants in liposomes improves their therapeutic potential against oxidant-induced lung damage because liposomes facilitate intracellular delivery and prolong the retention of entrapped agents inside the cell. In the present study, we compared the effectiveness of conventional N-acetylcysteine (NAC) and liposomal-NAC (L-NAC) against PQ-induced cytotoxicity and examined the mechanism(s) by which these antioxidant formulations conferred cytoprotection. The effects of NAC or L-NAC against PQ-induced cytotoxicity in A549 cells were assessed by measuring cellular PQ uptake, intracellular glutathione content, ROS levels, mitochondrial membrane potential, cellular gene expression, inflammatory cytokine release and cell viability. Pretreatment of cells with L-NAC was significantly more effective than pretreatment with the conventional drug in reducing PQ-induced cytotoxicity, as indicated by the biomarkers used in this study. Our results suggested that the delivery of NAC as a liposomal formulation improves its effectiveness in counteracting PQ-induced cytotoxicity. PMID:21584258

Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity

NASA Astrophysics Data System (ADS)

Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M.; Deng, Wei

2018-02-01

We developed light-triggered liposomes incorporating gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized by adjusting the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of HSPC: PE-NH2: gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of these liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox loaded liposomes were applied to human colorectal cancer cells, HCT116, and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity, compared to the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may have improved therapeutic efficacy in photodynamic therapy and chemotherapy.

Gold Nanoparticles Cytotoxicity

NASA Astrophysics Data System (ADS)

Mironava, Tatsiana

Over the last two decades gold nanoparticles (AuNPs) have been used for many scientific applications and have attracted attention due to the specific chemical, electronic and optical size dependent properties that make them very promising agents in many fields such as medicine, imagine techniques and electronics. More specifically, biocompatible gold nanoparticles have a huge potential for use as the contrast augmentation agent in X-ray Computed Tomography and Photo Acoustic Tomography for early tumor diagnostic as well these nanoparticles are extensively researched for enhancing the targeted cancer treatment effectiveness such as photo-thermal and radiotherapy. In most biomedical applications biocompatible gold nanoparticles are labeled with specific tumor or other pathology targeting antibodies and used for site specific drug delivery. However, even though gold nanoparticles poses very high level of anti cancer properties, the question of their cytotoxicity ones they are released in normal tissue has to be researched. Moreover, the huge amount of industrially produced gold nanoparticles raises the question of these particles being a health hazard, since the penetration is fairly easy for the "nano" size substances. This study focuses on the effect of AuNPs on a human skin tissue, since it is fall in both categories -- the side effects for biomedical applications and industrial workers and users' exposure during production and handling. Therefore, in the present project, gold nanoparticles stabilized with the biocompatible agent citric acid were generated and characterized by Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). The cytotoxic effect of AuNPs release to healthy skin tissue was modeled on 3 different cell types: human keratinocytes, human dermal fibroblasts, and human adipose derived stromal (ADS) cells. The AuNPs localization inside the cell was found to be cell type dependent. Overall cytotoxicity was found to be dependent

A novel paclitaxel-loaded poly(d,l-lactide-co-glycolide)-Tween 80 copolymer nanoparticle overcoming multidrug resistance for lung cancer treatment

PubMed Central

Yuan, Xun; Ji, Wenxiang; Chen, Si; Bao, Yuling; Tan, Songwei; Lu, Shun; Wu, Kongming; Chu, Qian

2016-01-01

Drug resistance has become a main obstacle for the effective treatment of lung cancer. To address this problem, a novel biocompatible nanoscale package, poly(d,l-lactide-co-glycolide)-Tween 80, was designed and synthesized to overcome paclitaxel (PTX) resistance in a PTX-resistant human lung cancer cell line. The poly(d,l-lactide-co-glycolide) (PLGA)-Tween 80 nanoparticles (NPs) could efficiently load PTX and release the drug gradually. There was an increased level of uptake of PLGA-Tween 80 in PTX-resistant lung cancer cell line A549/T, which achieved a significantly higher level of cytotoxicity than both PLGA NP formulation and Taxol®. The in vivo antitumor efficacy also showed that PLGA-Tween 80 NP was more effective than Taxol®, indicating that PLGA-Tween 80 copolymer was a promising carrier for PTX in resistant lung cancer. PMID:27307727

Effects of in vivo hydrocortisone on lymphocyte-mediated cytotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Katz, P.; Zaytoun, A.M.; Lee, J.H. Jr.

To examine the effects of in vivo hydrocortisone sodium succinate (HC) on natural killer (NK) cell and antibody-dependent cellular cytotoxicity (ADCC), 11 normal adults received a single intravenous bolus of 400 mg hydrocortisone. Lymphocytes were tested for NK activity and ADCC using 51chromium (51Cr)-release and single cell cytotoxicity assays against Molt-4 and sensitized RL O leads to target cells, respectively. Four hours after injection, both NK and ADCC activity were transiently increased in the 51Cr-release system. At 4 hours, there was a twofold increase in the relative frequency of potentially cytotoxic target binding cells but the absolute number of thesemore » cells did not change. However, the percentage lysis of bound targets at 4 hours was not altered. These data suggest that: 1) lymphocytes participating in NK and ADCC reactions are refractory to the kinetic and functional effects of HC; 2) the increased lytic activity observed at 4 hours is due to a selective depletion of noncytotoxic cells from the circulation; and 3) NK and ADCC activity did not differ in their responses to HC.« less

Cytotoxic and hemolytic effects of Tritrichomonas foetus on mammalian cells.

PubMed Central

Burgess, D E; Knoblock, K F; Daugherty, T; Robertson, N P

1990-01-01

Geographically distinct lines of Tritrichomonas foetus were assayed for their ability to cause cytotoxicity in nucleated mammalian cells and lysis of bovine erythrocytes. T. foetus was highly cytotoxic toward a human cervical cell line (HeLa) and early bovine lymphosarcoma (BL-3) but displayed low levels of cytotoxicity against African green monkey kidney (Vero) cells. In addition to variation in the extent of cytotoxicity toward different targets, differences in the levels of cytotoxicity in the same nucleated target occurred with different parasite lines. Whole T. foetus, unfractionated whole-cell extracts, and parasite-conditioned medium (RPMI 1640 without serum) all caused lysis of bovine erythrocytes. Lytic activity in the conditioned medium was substantially reduced by repeated freezing and thawing or heating to 90 degrees C for 30 min. Damage of mammalian target cells by live T. foetus could be reduced by the presence of protease inhibitors; however, such inhibitors did not diminish the lytic effects of conditioned medium. These results suggested that proteolytic enzymes were necessary for the lytic mechanism of the live parasites but were not required once lytic factors were released into the parasite-conditioned medium. They further suggested that the lytic molecules were either proteins or had proteinaceous components. Images PMID:2228233

Enhancement of mitomycin C-induced cytotoxicity by curcumin results from down-regulation of MKK1/2-ERK1/2-mediated thymidine phosphorylase expression.

PubMed

Weng, Shao-Hsing; Tsai, Min-Shao; Chiu, Yu-Fan; Kuo, Ya-Hsun; Chen, Huang-Jen; Lin, Yun-Wei

2012-03-01

Curcumin (diferuloylmethane), a phenolic compound obtained from the rhizome of Curcuma longa, has been found to inhibit cell proliferation in various human cancer cell lines, including non-small cell lung cancer (NSCLC). Thymidine phosphorylase (TP) is considered an attractive therapeutic target, because increased TP expression can suppress cancer cell death induced by DNA-damaging agents. Mitomycin C (MMC), a chemotherapeutic agent used to treat NSCLC, inhibits tumour growth through DNA cross-linking and breaking. Whether MMC can affect TP expression in NSCLC is unknown. Therefore, in this study, we suggested that curcumin enhances the effects of MMC-mediated cytotoxicity by decreasing TP expression and ERK1/2 activation. Exposure of human NSCLC cell lines H1975 and H1650 to curcumin decreased MMC-elicited phosphorylated MKK1/2-ERK1/2 protein levels. Moreover, curcumin significantly decreased MMC-induced TP protein levels by increasing TP mRNA and protein instability. Enhancement of ERK1/2 activation by constitutively active MKK1/2 (MKK1/2-CA) increased TP protein levels and cell viability in curcumin- and MMC-co-treated cells. In contrast, U0126, a MKK1/2 inhibitor, augmented the cytotoxic effect and the down-regulation of TP by curcumin and MMC. Specific inhibition of TP by siRNA significantly enhanced MMC-induced cell death and cell growth inhibition. Our results suggest that suppression of TP expression or administration of curcumin along with MMC may be a novel lung cancer therapeutic modality in the future. © 2011 The Authors. Basic & Clinical Pharmacology & Toxicology © 2011 Nordic Pharmacological Society.

Curcumin downregulates p38 MAPK-dependent X-ray repair cross-complement group 1 (XRCC1) expression to enhance cisplatin-induced cytotoxicity in human lung cancer cells.

PubMed

Tung, Chun-Liang; Jian, Yi-Jun; Chen, Jyh-Cheng; Wang, Tai-Jing; Chen, Wen-Ching; Zheng, Hao-Yu; Chang, Po-Yuan; Liao, Kai-Sheng; Lin, Yun-Wei

2016-06-01

Cisplatin is a well-studied and widely used chemotherapeutic agent and is effective in the treatment of the advanced human non-small cell lung cancer (NSCLC). Curcumin is a yellow pigment derived from the rhizome of Curcuma longa and has been proved to have antioxidant and antitumor properties. XRCC1 is an important scaffold protein involved in base excision repair and plays an important role in the development of lung cancer. In this study, we characterize the role of curcumin in the cytotoxicity, p38 MAPK activation, and XRCC1 expression affected by cisplatin in NSCLC cells. We show that curcumin enhanced the cytotoxicity induced by cisplatin in two NSCLC cells, A549 and H1703. Treatment with cisplatin alone increased XRCC1 mRNA and protein expression through p38 MAPK activation. Moreover, SB2023580 (p38 inhibitor) decreased the XRCC1 mRNA and protein stability upon cisplatin treatment. Knockdown of XRCC1 in NSCLC cells by transfection of XRCC1 siRNA or inactivation of p38 MAPK resulted in enhancing the cytotoxicity and cell growth inhibition induced by cisplatin. Curcumin inhibited the expression of XRCC1 in cisplatin-exposed NSCLC cells. Furthermore, transfection with constitutive active MKK6 or HA-p38 MAPK vectors rescued the XRCC1 protein level and also the cell survival suppressed by cisplatin and curcumin combination in A549 and H1703 cells. These findings suggested that the downregulation of XRCC1 expression by curcumin can enhance the chemosensitivity of cisplatin in NSCLC cells.

Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers.

PubMed

van Haaften, Caroline; Duke, Colin C; Weerheim, Arij M; Smit, Nico Pm; van Haard, Paul Mm; Darroudi, Firouz; Trimbos, Baptist Jmz

2011-03-14

Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue.In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid.Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL).Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects.Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. For the first time both crude plant extract

Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers

PubMed Central

2011-01-01

Background Ovarian cancer remains the leading cause of death from gynaecological malignancy. More than 60% of the patients are presenting the disease in stage III or IV. In spite of combination of chemotherapy and surgery the prognosis stays poor for therapy regimen. Methods The leaves of a plant endemic to Australia, Calomeria amaranthoides, were extracted and then fractionated by column chromatography. In vitro cytotoxicity tests were performed with fractions of the plant extract and later with an isolated compound on ovarian cancer cell lines, as well as normal fibroblasts at concentrations of 1-100 μg/mL (crude extract) and 1-10 μg/mL (compound). Cytotoxicity was measured after 24, 48 and 72 hours by using a non-fluorescent substrate, Alamar blue. In vivo cytotoxicity was tested on ascites, developed in the abdomen of nude mice after inoculation with human OVCAR3 cells intraperitoneally. The rate of change in abdomen size for the mice was determined by linear regression and statistically evaluated for significance by the unpaired t test. Results Two compounds were isolated by chromatographic fractionation and identified by 1H-NMR, 13C-NMR and mass spectrometry analyses, EPD, an α-methylene sesquiterpene lactone of the eremophilanolide subtype, and EPA, an α-methylene carboxylic acid. Cytotoxicity of EPD for normal fibroblasts at all time points IC50 was greater than 10 μg/mL, whereas, for OVCAR3 cells at 48 hours IC50 was 5.3 μg/mL (95% confidence interval 4.3 to 6.5 μg/mL). Both, the crude plant extract as well as EPD killed the cancer cells at a final concentration of 10 μg/mL and 5 μg/mL respectively, while in normal cells only 20% cell killing effect was observed. EPA had no cytotoxic effects. Changes in abdomen size for control versus Cisplatin treated mice were significantly different, P = 0.023, as were control versus EPD treated mice, P = 0.025, whereas, EPD versus Cisplatin treated mice were not significantly different, P = 0.13. Conclusions

Aptamer-functionalized PEG-PLGA nanoparticles for enhanced anti-glioma drug delivery.

PubMed

Guo, Jianwei; Gao, Xiaoling; Su, Lina; Xia, Huimin; Gu, Guangzhi; Pang, Zhiqing; Jiang, Xinguo; Yao, Lei; Chen, Jun; Chen, Hongzhuan

2011-11-01

Targeted delivery of therapeutic nanoparticles in a disease-specific manner represents a potentially powerful technology especially when treating infiltrative brain tumors such as gliomas. We developed a nanoparticulate drug delivery system decorated with AS1411 (Ap), a DNA aptamer specifically binding to nucleolin which was highly expressed in the plasma membrane of both cancer cells and endothelial cells in angiogenic blood vessels, as the targeting ligand to facilitate anti-glioma delivery of paclitaxel (PTX). Ap was conjugated to the surface of PEG-PLGA nanoparticles (NP) via an EDC/NHS technique. With the conjugation confirmed by Urea PAGE and XPS, the resulting Ap-PTX-NP was uniformly round with particle size at 156.0 ± 54.8 nm and zeta potential at -32.93 ± 3.1 mV. Ap-nucleolin interaction significantly enhanced cellular association of nanoparticles in C6 glioma cells, and increased the cytotoxicity of its payload. Prolonged circulation and enhanced PTX accumulation at the tumor site was achieved for Ap-PTX-NP, which eventually obtained significantly higher tumor inhibition on mice bearing C6 glioma xenografts and prolonged animal survival on rats bearing intracranial C6 gliomas when compared with PTX-NP and Taxol(®). The results of this contribution demonstrated the potential utility of AS1411-functionalized nanoparticles for a therapeutic application in the treatment of gliomas. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cancer cell specific cytotoxic effect of Rhoeo discolor extracts and solvent fractions.

PubMed

García-Varela, Rebeca; Fajardo Ramírez, Oscar Raúl; Serna-Saldivar, Sergio O; Altamirano, Julio; Cardineau, Guy A

2016-08-22

Traditional or folk medicine has led to the discovery of important bioactive substances used in several health-related areas. Phytochemicals in Rhoeo discolor (R. discolor) extracts have proven to have important cancer cell specific cytotoxic activity. In the present research, we determined the cytotoxic effect of extracts of R. discolor, a plant commonly used in Mexico for both medicinal and ornamental purposes. We evaluated the cytotoxic effects against three representative human cancer cell lines: HT-29 colon cancer, Hep-G2 liver cancer and PC-3 prostate cancer cell lines, as well as a control fibroblast cell line NIH 3T3. Ten different crude extracts were tested along with fractions derived from the five most bioactive crude extracts. Analytical data, HPLC-MS-TOF, revealed a high content of phenolic compounds such as anthocyanins, ferulic, vanillic, chlorogenic and p-coumaric acid in the extracts. Phenolic compounds have previously been reported as health beneficial with antioxidant and potential cancer specific cytotoxic effects. Studies revealed that low concentrations of these crude bioactive extracts (10µg/ml) and their fractions (50µg/ml) were effective as cancer specific cytotoxic agents, since they caused a significant proliferation inhibition on cancer cell lines (up to 94.2% in HT-29, 92.9% in Hep-G2 and 61.8% in PC-3 of apoptosis induction) with little harm to the control cell line (no higher than 28.3% apoptosis induction), and, importantly, the most effective extracts were mainly water, methanol and ethanol based. These results suggest that a diet containing these compounds may function as a medical aid or chemoprotective. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Anti-apoptotic effect of esculin on dopamine-induced cytotoxicity in the human neuroblastoma SH-SY5Y cell line.

PubMed

Zhao, Da-Long; Zou, Li-Bo; Lin, Sheng; Shi, Jian-Gong; Zhu, Hai-Bo

2007-11-01

Dopamine (DA), as a neurotoxin, can elicit severe Parkinson's disease-like syndrome by elevating intracellular reactive oxygen species (ROS) levels and apoptotic activity. In this study, we examined the effect of esculin, which was extracted from Fraxinus sielboldiana blume, on DA-induced cytotoxicity and the underlying mechanism in human neuroblastoma SH-SY5Y cells. Our results suggest that the protective effects of esculin (10(-7), 10(-6) and 10(-5) M) on DA-induced cytotoxicity may be ascribed to its anti-oxidative properties by reducing ROS level, and its anti-apoptotic effect via protecting mitochondrion membrane potential (DeltaPsim), enhancing superoxide dismutaese (SOD) activity and reduced glutathione (GSH) levels, and regulating P53, Bax and Bcl-2 expression. In addition, esculin inhibited the release of cytochrome c and apoptosis-inducing factor (AIF), and the protein expression of activated caspase 3. These data indicate that esculin may provide a useful therapeutic strategy for the treatment of progressive neurodegenerative diseases such as Parkinson's disease (PD).

[Cytotoxic effect of Vibrio cholerae non-O1 on Vero cells].

PubMed

Figueroa-Arredondo, P; García-Lozano, H; Gutiérrez-Cogco, L; Valdespino-Gómez, J L

1994-01-01

At the present time there is still in Mexico a diarrhoeal outbreak due to Vibrio cholerae O1. In INDRE we have isolated from the same outbreak last year (jan-apr), 70 strains of Vibrio cholerae Non-O1. These were isolated from patients with a diarrhoeal illness different from cholera. Patients were of different ages and sex, and from various geographic areas. The isolated strains were confirmed by serological agglutination test with polyclonal antisera, and they neither belong to O1 serogroup or O139. We assayed all the 70 strains in Vero cells, searching for cytotoxic effect, probably attributed to cholera toxin, or any other toxin. The strains were screened by PCR for cholera toxin gene detection, and negative results were obtained. We have found only one CT-producer strain, but it was a rough one so, we are not able to affirm that is not a V. cholerae O1 serotype. Vibrio cholerae Non-O1 strains, tested in Vero cells assay, produced cytotoxic effect within 24 h. It was found that 48/70 strains (66.6%), had cytotoxic activity, showing rounding and then lysis of cells. From our results we concluded that this cytotoxic effect, is not cholera toxin related, instead we propose it could be due to an unknown virulence factor, probably a different toxin in mexican Vibrio cholerae Non-O1 strains.

Cytotoxic Effect Associated with Overexpression of QNR Proteins in Escherichia coli.

PubMed

Machuca, Jesús; Diaz de Alba, Paula; Recacha, Esther; Pascual, Álvaro; Rodriguez-Martinez, José Manuel

2017-10-01

The objective was to evaluate the cytotoxic effect associated with overexpression of multiple Qnr-like plasmid-mediated quinolone resistance (PMQR) mechanisms in Escherichia coli. Coding regions of different PMQR genes (qnrA1, qnrB1, qnrC, qnrD1, qnrS1, and qepA2) and efsqnr were cloned into pET29a(+) vector and overexpressed in E. coli BL21. E. coli BL21 with and without an empty pET29a(+) vector were used as controls. The cytotoxic effect associated with PMQR mechanism overexpression was determined by transmission electron microscopy and viability assays. Overexpressed qnr genes produced loss of bacterial viability in the range of 77-97% compared with the controls, comparable with loss of viability associated with EfsQnr overexpression (97%). No loss of viability was observed in E. coli overexpressing QepA2. In transmission electron microscopy assays, signs of cytotoxicity were observed in E. coli cells overexpressing EfsQnr and Qnr proteins (30-45% of the bacterial population showed morphological changes). Morphological changes were observed in less than 5% of bacterial populations from the control strains and E. coli overexpressing QepA2. Overexpression of qnr genes produces a cytotoxic cellular and structural effect in E. coli, the magnitude of which varies depending on the family of Qnr proteins.

Immunomodulatory properties of medicinal mushrooms: differential effects of water and ethanol extracts on NK cell-mediated cytotoxicity.

PubMed

Lu, Chia-Chen; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Martel, Jan; Ojcius, David M; Ko, Yun-Fei; Lai, Hsin-Chih; Young, John D

2016-10-01

Medicinal mushrooms have been used for centuries in Asian countries owing to their beneficial effects on health and longevity. Previous studies have reported that a single medicinal mushroom may produce both stimulatory and inhibitory effects on immune cells, depending on conditions, but the factors responsible for this apparent dichotomy remain obscure. We show here that water and ethanol extracts of cultured mycelium from various species (Agaricus blazei Murrill, Antrodia cinnamomea, Ganoderma lucidum and Hirsutella sinensis) produce opposite effects on NK cells. Water extracts enhance NK cell cytotoxic activity against cancer cells, whereas ethanol extracts inhibit cytotoxicity. Water extracts stimulate the expression and production of cytolytic proteins (perforin and granulysin) and NKG2D/NCR cell surface receptors, and activate intracellular signaling kinases (ERK, JNK and p38). In contrast, ethanol extracts inhibit expression of cytolytic and cell surface receptors. Our results suggest that the mode of extraction of medicinal mushrooms may determine the nature of the immunomodulatory effects produced on immune cells, presumably owing to the differential solubility of stimulatory and inhibitory mediators. These findings have important implications for the preparation of medicinal mushrooms to prevent and treat human diseases. © The Author(s) 2016.

Thioredoxin reductase 1 knockdown enhances selenazolidine cytotoxicity in human lung cancer cells via mitochondrial dysfunction

PubMed Central

Poerschke, Robyn L.; Moos, Philip J.

2010-01-01

Thioredoxin reductase (TR1) is a selenoprotein that is involved in cellular redox status control and deoxyribonucleotide biosynthesis. Many cancers, including lung, overexpress TR1, making it a potential cancer therapy target. Previous work has shown that TR1 knockdown enhances the sensitivity of cancer cells to anticancer treatments, as well as certain selenocompounds. However, it is unknown if TR1 knockdown produces similar effect on the sensitivity of human lung cancer cells. To further elucidate the role of TR1 in the mechanism of selenocompounds in lung cancer, a lentiviral microRNA delivery system to knockdown TR1 expression in A549 human lung adenocarcinoma cells was utilized. Cell viability was assessed after 48 hr treatment with the selenocysteine prodrug selenazolidines 2-butylselenazolidine-4(R)-carboxylic acid (BSCA) and 2-cyclohexylselenazolidine-4-(R)-carboxylic acid (ChSCA), selenocystine (SECY), methylseleninic acid (MSA), 1,4-phenylenebis(methylene)selenocyanate (p-XSC), and selenomethionine (SEM). TR1 knockdown increased the cytotoxicity of BSCA, ChSCA, and SECY but did not sensitize cells to MSA, SEM, or p-XSC. GSH and TR1 depletion together decreased cell viability, while no change was observed with GSH depletion alone. Reactive oxygen species generation was induced only in TR1 knockdown cells treated with the selenazolidines or SECY. These three compounds also decreased total intracellular glutathione levels and oxidized thioredoxin, but in a TR1 independent manner. TR1 knockdown increased selenazolidine and SECY-induced mitochondrial membrane depolarization, as well as DNA strand breaks and AIF translocation from the mitochondria. These results indicate the ability of TR1 to modulate the cytotoxic effects of BSCA, ChSCA and SECY in human lung cancer cells through mitochondrial dysfunction. PMID:20920480

Cholera toxin B-subunit gene enhances mucosal immunoglobulin A, Th1-type, and CD8+ cytotoxic responses when coadministered intradermally with a DNA vaccine.

PubMed

Sanchez, Alba E; Aquino, Guillermo; Ostoa-Saloma, Pedro; Laclette, Juan P; Rocha-Zavaleta, Leticia

2004-07-01

A plasmid vector encoding the cholera toxin B subunit (pCtB) was evaluated as an intradermal genetic adjuvant for a model DNA vaccine expressing the human papillomavirus type 16 L1 capsid gene (p16L1) in mice. p16L1 was coadministered with plasmid pCtB or commercial polypeptide CtB as a positive control. Coadministration of pCtB induced a significant increment of specific anti-L1 immunoglobulin A (IgA) antibodies in cervical secretions (P < 0.05) and fecal extracts (P < 0.005). Additionally, coadministration of pCtB enhanced the production of interleukin-2 and gamma interferon by spleen cells but did not affect the production of interleukin-4, suggesting a Th1-type helper response. Furthermore, improved CD8+ T-cell-mediated cytotoxic activity was observed in mice vaccinated with the DNA vaccine with pCtB as an adjuvant. This adjuvant effect was comparable to that induced by the CtB polypeptide. These results indicate that intradermal coadministration of pCtB is an adequate means to enhance the mucosa-, Th1-, and CD8(+)-mediated cytotoxic responses induced by a DNA vaccine.

Cytotoxic Drug Dispersal, Cytotoxic Safety, and Cytotoxic Waste Management: Practices and Proposed India-specific Guidelines

PubMed Central

Capoor, Malini R; Bhowmik, Kumar Tapas

2017-01-01

This article deals with practices related to cytotoxic drug dispersal, cytotoxic safety, and cytotoxic waste management and attempts at India-specific guidelines for their dispersal and disposal. The articles related to cytotoxic drug dispersal, cytotoxic safety, and cytotoxic waste management were reviewed from PubMed and their applicability in Indian health-care facilities (HCFs) was also reviewed. All HCFs dealing with cytotoxic drugs should consider cytotoxic policy, patient safety and health-care worker safety, and environmental monitoring program as per the available international guidelines customized as per Indian conditions. Utmost care in handling cytotoxic waste is quintessential. The formation of India-specific cytotoxic guidelines requires the inputs from all stakeholders. Cytotoxic waste, cytotoxic safety, and cytotoxic waste management should be the subject of a national strategy with an infrastructure, cradle-to-grave legislation, competent regulatory authority, and trained personnel. PMID:28900329

Stimulation of Breast Tumor Cell Proliferative Recovery by the Peptide Hormone Erythropoietin

DTIC Science & Technology

2006-08-01

against apoptosis induced by chemotherapy, F-MEL leukemic cells treated with or without EPO were exposed to either cytarabine (Ara-C) or daunorubicin...F-MEL erythroleukemia cells is suppressed by treatment with cytarabine ( Ara C) or daunorubicin. Cells were incubated in the absence or presence...antiproliferative and/or cytotoxic effects of Adriamycin,Taxol, and tamoxifen in breast tumor cells (or of cytarabine and daunorubicin in F-MEL cells). EPO failed to

Shenmai injection enhances the cytotoxicity of chemotherapeutic drugs against colorectal cancers via improving their subcellular distribution

PubMed Central

Liu, Wen-yue; Zhang, Jing-wei; Yao, Xue-quan; Jiang, Chao; He, Ji-chao; Ni, Pin; Liu, Jia-li; Chen, Qian-ying; Li, Qing-ran; Zang, Xiao-jie; Yao, Lan; Liu, Ya-zhong; Wang, Mu-lan; Shen, Pei-qiang; Wang, Guang-ji; Zhou, Fang

2017-01-01

Shenmai injection (SMI) is a Chinese patent-protected injection, which was mainly made of Red Ginseng and Radix Ophiopogonis and widely used for treating coronary heart disease and tumors by boosting Qi and nourishing Yin. In this study we examined whether SMI could produce direct synergetic effects on the cytoxicity of adriamycin (ADR) and paclitaxel (PTX) in colorectal cancers in vivo and in vitro, and explored the underlying pharmacokinetic mechanisms. BALB/c nude mice with LoVo colon cancer xenografts were intraperitoneally injected with ADR (2 mg·kg−1·3d−1) or PTX (7.5 mg·kg−1·3d−1) with or without SMI (0.01 mL·g−1·d−1) for 13 d. Co-administration of SMI significantly enhanced the chemotherapeutic efficacy of ADR and PTX, whereas administration of SMI alone at the given dosage did not produce visible anti-cancer effects, The chemosensitizing action of SMI was associated with increased concentrations of ADR and PTX in the plasma and tumors. In Caco-2 and LoVo cells in vitro, co-treatment with SMI (2 μL/mL) significantly enhanced the cytotoxicity of ADR and PTX, and resulted in some favorable pharmacokinetic changes in the subcellular distribution of ADR and PTX. In addition, SMI-induced intracellular accumulation of ADR was closely correlated with the increased expression levels of P-glycoprotein in 4 colon cancer cell lines (r2=+0.8558). SMI enhances the anti-cancer effects of ADR and PTX in colon cancers in vivo and in vitro by improving the subcellular distributions of ADR and PTX. PMID:27867186

Cytotoxic, antioxidative, genotoxic and antigenotoxic effects of Horchata, beverage of South Ecuador.

PubMed

Bailon-Moscoso, Natalia; Tinitana, Fani; Martínez-Espinosa, Ruth; Jaramillo-Velez, Andrea; Palacio-Arpi, Alejandra; Aguilar-Hernandez, Jessica; Romero-Benavides, Juan Carlos

2017-12-19

"Horchata" is an herbal mixture infusion consumed in Southern Ecuador; 66% of its plants are anti-inflammatory medicinal plant, and 51% are analgesics. Anti-inflammatory substances can prevent carcinogenesis mediated by cytotoxic effects and can prevent DNA damage. The aim of this study was to evaluate the cytotoxicity and apoptotic/antigenotoxic effects of horchata as well as its mechanism. Nine different varieties of horchata were prepared in the traditional way and then freeze-dried. Phytochemical screening tested for the presence of secondary metabolites using standard procedures and antioxidant activities. The cytotoxic activity was evaluated on cerebral astrocytoma (D-384), prostate cancer (PC-3), breast cancer (MCF-7), colon cancer (RKO), lung cancer (A-549), immortalized Chinese hamster ovary cells (CHO-K1), and human peripheral blood lymphocytes via a MTS assay. The pro-apoptotic effects were evaluated with Anexin V/Propidium Iodide and western blot of Bax, Bcl-2, TP53, and TP73. Induction and reduction of ROS were assessed by fluorimetry. Genotoxic and antigenotoxic effects were evaluated with a comet assay and micronuclei on binucleated cells. Five of nine horchatas had cytotoxic effects against D-384 while not affecting normal cells. These horchatas induce cell death by apoptosis modulated by p53/p73. In CHO-K1 cells, the horchatas decrease the damage induced by hydrogen peroxide and Mitomycin C measured in the comet and micronucleus assay respectively. The IC 50 range of effective horchatas in D-384 was 41 to 122 μg·mL -1 . This effect may be related to its use in traditional medicine (brain tonic). On the other hand, immortalized Chinese hamster ovary cells (CHO-K1) and lymphocytes did not show a cytotoxic effect. The most potent horchata induced apoptosis via a p53/p73-mediated mechanism. The horchatas present antigenotoxic properties, which may be related to the antioxidant capacity. Future studies on horchata components are necessary to

Down-regulation of ERK1/2 and AKT-mediated X-ray repair cross-complement group 1 protein (XRCC1) expression by Hsp90 inhibition enhances the gefitinib-induced cytotoxicity in human lung cancer cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tung, Chun-Liang; Jian, Yi-Jun; Department of Biochemical Science and Technology, National Chiayi University, 300 Syuefu Road, Chiayi 600, Taiwan

2015-05-15

Gefitinib (Iressa{sup R}, ZD1839) is a selective epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) that blocks growth factor-mediated cell proliferation and extracellular signal-regulated kinases 1/2 (ERK1/2) and AKT signaling activation. It has been shown that inhibition of Hsp90 function can enhance antitumor activity of EGFR-TKI. XRCC1 is an important scaffold protein in base excision repair, which could be regulated by ERK1/2 and AKT pathways. However, the role of ERK1/2 and AKT-mediated XRCC1 expression in gefitinib alone or combination with an Hsp90 inhibitor-induced cytotoxicity in non-small cell lung cancer (NSCLC) cells has not been identified. In this study, gefitinib treatment decreasedmore » XRCC1 mRNA and protein expression through ERK1/2 and AKT inactivation in two NSCLC cells, A549 and H1975. Knocking down XRCC1 expression by transfection with small interfering RNA of XRCC1 enhanced the cytotoxicity and cell growth inhibition of gefitinib. Combining treatment of gefitinib with an Hsp90 inhibitor resulted in enhancing the reduction of XRCC1 protein and mRNA levels in gefitinib-exposed A549 and H1975 cells. Compared to a single agent alone, gefitinib combined with an Hsp90 inhibitor resulted in cytotoxicity and cell growth inhibition synergistically in NSCLC cells. Furthermore, transfection with constitutive active MKK1 or AKT vectors rescued the XRCC1 protein level as well as the cell survival suppressed by an Hsp90 inhibitor and gefitinib. These findings suggested that down-regulation of XRCC1 can enhance the sensitivity of gefitinib for NSCLC cells. - Highlights: • Gefitinib treatment decreased XRCC1 mRNA and protein expression in NSCLC cells. • Knocking down XRCC1 expression enhanced the cytotoxic effect of gefitinib. • Gefitinib combined with an Hsp90 inhibitor resulted in synergistically cytotoxicity.« less

Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity.

PubMed

Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M; Deng, Wei

2017-01-01

We developed light-triggered liposomes incorporating 3-5 nm hydrophobic gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized for varying the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of hydrogenated soy l-α-phosphatidylcholine:1,2-dioleoyl- sn -glycero-3-phosphoethanolamine- N -(hexanoylamine):gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of gold-loaded liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox-loaded liposomes were applied to human colorectal cancer cells (HCT116) and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity compared with the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy.

Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity

PubMed Central

Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M; Deng, Wei

2017-01-01

We developed light-triggered liposomes incorporating 3–5 nm hydrophobic gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized for varying the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of hydrogenated soy l-α-phosphatidylcholine:1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(hexanoylamine):gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of gold-loaded liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox-loaded liposomes were applied to human colorectal cancer cells (HCT116) and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity compared with the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy. PMID:28203076

Emodin enhances cisplatin-induced cytotoxicity in human bladder cancer cells through ROS elevation and MRP1 downregulation.

PubMed

Li, Xinxing; Wang, Haolu; Wang, Juan; Chen, Yuying; Yin, Xiaobin; Shi, Guiying; Li, Hui; Hu, Zhiqian; Liang, Xiaowen

2016-08-02

Chemoresistance is one of the most leading causes for tumor progression and recurrence of bladder cancer. Reactive oxygen species (ROS) plays a key role in the chemosensitivity of cancer cells. In the present study, emodin (1,3,8-trihydroxy-6-methylanthraquinone) was applied as a ROS generator in combination with cisplatin in T24 and J82 human bladder cancer cells. Cell viability and apoptosis rate of different treatment groups were detected by 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and flow cytometry (FCM). The expression of transporters was measured at both the transcription and translation levels using PCR and western blotting. In vitro findings were confirmed by in vivo experiments using tumor-bearing mice. The expression of multidrug resistance-associated protein 1 (MRP1) in tumour tissue was measured using immunohistochemistry and side effects of the emodin/cisplatin co-treatment were investigated by histological examination. Emodin increased the cellular ROS level and effectively enhanced the cisplatin-induced cytotoxicity of T24 and J82 human bladder cancer cells through decreasing glutathione-cisplatin (GSH-cisplatin) conjugates. It blocked the chemoresistance of T24 and J82 cells to cisplatin through suppressing the expression of MRP1. This effect was specific in T24 and J82 cells but not in HCV-29 normal bladder epithelial cells. Consistent with in vitro experiments, emodin/cisplatin co-treatment increased the cell apoptosis and repressed the MRP1 expression in xenograft tumors, and without obvious systemic toxicity. This study revealed that emodin could increase the cisplatin-induced cytotoxicity against T24 and J82 cells via elevating the cellular ROS level and downregulating MRP1 expression. We suggest that emodin could serve as an effective adjuvant agent for the cisplatin-based chemotherapy of bladder cancer.

Selective cytotoxic effect of non-thermal micro-DBD plasma

NASA Astrophysics Data System (ADS)

Kwon, Byung-Su; Choi, Eun Ha; Chang, Boksoon; Choi, Jeong-Hyun; Kim, Kyung Sook; Park, Hun-Kuk

2016-10-01

Non-thermal plasma has been extensively researched as a new cancer treatment technology. We investigated the selective cytotoxic effects of non-thermal micro-dielectric barrier discharge (micro-DBD) plasma in cervical cancer cells. Two human cervical cancer cell lines (HeLa and SiHa) and one human fibroblast (HFB) cell line were treated with micro-DBD plasma. All cells underwent apoptotic death induced by plasma in a dose-dependent manner. The plasma showed selective inhibition of cell proliferation in cervical cancer cells compared to HFBs. The selective effects of the plasma were also observed between the different cervical cancer cell lines. Plasma treatment significantly inhibited the proliferation of SiHa cells in comparison to HeLa cells. The changes in gene expression were significant in the cervical cancer cells in comparison to HFBs. Among the cancer cells, apoptosis-related genes were significantly enriched in SiHa cells. These changes were consistent with the differential cytotoxic effects observed in different cell lines.

Enhanced anti-tumor activity and cytotoxic effect on cancer stem cell population of metformin-butyrate compared with metformin HCl in breast cancer.

PubMed

Lee, Kyung-Min; Lee, Minju; Lee, Jiwoo; Kim, Sung Wuk; Moon, Hyeong-Gon; Noh, Dong-Young; Han, Wonshik

2016-06-21

Metformin, which is a drug commonly used to treat type 2 diabetes, has shown anti-tumor effects in numerous experimental, epidemiologic, observational, and clinical studies. Here, we report a new metformin derivative, metformin-butyrate (MFB). Compared to metformin-HCl, it more potently activates AMPK, inhibits mTOR, and impairs cell cycle progression at S and G2/M phases. Moreover, MFB inhibits the mammosphere formation of breast cancer cells and shows cytotoxic effects against CD44+CD24-/low populations in vitro and in vivo, indicating that it might have preferential effects on the cancer stem cell population. MFB showed synergistic cytotoxicity with docetaxel and cisplatin, and MFB pretreatment of breast cancer cells prior to their injection into the mammary fat pads of mice significantly decreased the obtained xenograft tumor volumes, compared with untreated or metformin-pretreated cells. Overall, MFB showed greater anti-neoplastic activity and greater efficacies in targeting the G2/M phase and breast cancer stem cell population, compared to metformin-HCl. This suggests that MFB may be a promising therapeutic agent against aggressive and resistant breast cancers.

In vitro cytotoxicity of Manville Code 100 glass fibers: Effect of fiber length on human alveolar macrophages

PubMed Central

Zeidler-Erdely, Patti C; Calhoun, William J; Ameredes, Bill T; Clark, Melissa P; Deye, Gregory J; Baron, Paul; Jones, William; Blake, Terri; Castranova, Vincent

2006-01-01

-exposed human macrophage cultures. In contrast, rat macrophages exhibited both incomplete phagocytosis of long fibers and length-dependent toxicity. The results of the human and rat cell studies suggest that incomplete engulfment may enhance cytotoxicity of fiber glass. However, the possibility should not be ruled out that differences between human versus rat macrophages other than cell diameter could account for differences in fiber effects. PMID:16569233

Curcumin-cyclodextrin encapsulated chitosan nanoconjugates with enhanced solubility and cell cytotoxicity.

PubMed

Popat, Amirali; Karmakar, Surajit; Jambhrunkar, Siddharth; Xu, Chun; Yu, Chengzhong

2014-05-01

Curcumin (CUR), a naturally derived anti-cancer cocktail is arguably the most widely studied neutraceutical. Despite a lot of promises, it is yet to reach the market as an active anti-cancer formulation. In the present study, we have prepared highly soluble (3 mg/ml) CUR-γ-hydroxypropyl cyclodextrin (CUR-CD) hollow spheres. CUR-CD hollow spheres were prepared by a novel and scalable spray drying method. CUR-CD was then encapsulated into positively charged biodegradable chitosan (CUR-CD-CS) nanoparticles. The CUR-CD-CS nanoparticles were characterised by TEM, SEM, DLS, drug loading and in vitro release. We tested the efficacy of these CUR-CD-CS nanoparticles in SCC25 cell lines using MTT assay and investigated its cellular uptake mechanism. We also studied Oligo DNA loading in CUR-CD-CS nanoparticles and its delivery via confocal imaging and FACS analysis. Our results demonstrated that CUR-CD-CS nanoparticles showed superior in vitro release performance and higher cytotoxicity in SCC25 cell line amongst all tested formulations. The cytotoxicity results were corroborated by cell cycle analysis and apoptosis test, showing nearly 100% apoptotic cell death in the case of CUR-CD-CS nanoparticles. Compared to CS nanoparticles, CS-CD nanoformulation showed higher cellular delivery of Cy3-Oligo DNA which was tested quantitatively using flowcytometry analysis, indicating that CD not only enhanced CUR solubility but also boosted the cellular uptake. Our study shows that rationally designed bio-degradable natural biomaterials have great potential as next generation nano-carriers for hydrophobic drug delivery such as CUR with potential of dual drug-gene delivery. Copyright © 2014 Elsevier B.V. All rights reserved.

Optimizing the design and in vitro evaluation of bioreactive glucose oxidase-microspheres for enhanced cytotoxicity against multidrug resistant breast cancer cells.

PubMed

Cheng, Ji; Liu, Qun; Shuhendler, Adam J; Rauth, Andrew M; Wu, Xiao Yu

2015-06-01

Glucose oxidase (GOX) encapsulated in alginate-chitosan microspheres (GOX-MS) was shown in our previous work to produce reactive oxygen species (ROS) in situ and exhibit anticancer effects in vitro and in vivo. The purpose of present work was to optimize the design and thus enhance the efficacy of GOX-MS against multidrug resistant (MDR) cancer cells. GOX-MS with different mean diameters of 4, 20 or 140 μm were prepared using an emulsification-internal gelation-adsorption-chitosan coating method with varying compositions and conditions. The GOX loading efficiency, loading level, relative bioactivity of GOX-MS, and GOX leakage were determined and optimal chitosan concentrations in the coating solution were identified. The influence of particle size on cellular uptake, ROS generation, cytotoxicity and their underlying mechanisms was investigated. At the same GOX dose and incubation time, smaller sized GOX-MS produced larger amounts of H2O2 in cell culture medium and greater cytotoxicity toward murine breast cancer MDR (EMT6/AR1.0) and wild type (EMT6/WT) cells. Fluorescence and confocal laser scanning microscopy revealed significant uptake of small sized (4 μm) GOX-MS by both MDR and WT cells, but no cellular uptake of large (140 μm) GOX-MS. The GOX-MS were equally effective in killing both MDR cells and WT cells. The cytotoxicity of the GOX formulations was positively correlated with membrane damage and lipid peroxidation. GOX-MS induced greater membrane damage and lipid peroxidation in MDR cells than the WT cells. These results suggest that the optimized, small micron-sized GOX-MS are highly effective against MDR breast cancer cells. Copyright © 2015 Elsevier B.V. All rights reserved.

Cytotoxicity of denture base resins: effect of water bath and microwave postpolymerization heat treatments.

PubMed

Jorge, Janaina Habib; Giampaolo, Eunice Teresinha; Vergani, Carlos Eduardo; Machado, Ana Lúcia; Pavarina, Ana Cláudia; Carlos, Iracilda Zeppone

2004-01-01

This study compared the effect of two postpolymerization heat treatments on the cytotoxicity of three denture base resins on L929 cells using 3H-thymidine incorporation and MTT assays. Sample disks of Lucitone 550, QC 20, and Acron MC resins were fabricated under aseptic conditions and stored in distilled water at 37 degrees C for 48 hours. Specimens were then divided into three groups: (1) heat treated in microwave oven for 3 minutes at 500 W; (2) heat treated in water bath at 55 degrees C for 60 minutes; and (3) no heat treatment. Eluates were prepared by placing three disks into a sterile glass vial with 9 mL of Eagle's medium and incubating at 37 degrees C for 24 hours. The cytotoxic effect from the eluates was evaluated using the 3H-thymidine incorporation and MTT assays, which reflect DNA synthesis levels and cell metabolism, respectively. The components leached from the resins were cytotoxic to L929 cells when 3H-thymidine incorporation assay was employed. In contrast, eluates from all resins revealed noncytotoxic effects as measured by MTT assay. For both MTT assay and 3H-thymidine incorporation, the heat treatments did not decrease the cytotoxicity of the materials tested. Resins were graded by 3H-thymidine incorporation assay as slightly cytotoxic and by MTT assay as noncytotoxic. Cytotoxicity of the denture base materials was not influenced by microwave or water bath heat treatment.

Effect of N-acetyl cysteine on orthodontic primers cytotoxicity.

PubMed

D'Antò, Vincenzo; Spagnuolo, Gianrico; Schweikl, Helmut; Rengo, Sandro; Ambrosio, Luigi; Martina, Roberto; Valletta, Rosa

2011-02-01

The aims of this study were to evaluate the cytotoxicity of four orthodontic primers, including two hydrophilic and two hydrophobic materials, and to investigate the role of the reactive oxygen species (ROS) in induced cell damage. Moreover, the effects of the anti-oxidant N-acetyl cysteine (NAC) on primers toxicity was analyzed. Human gingival fibroblasts (HGF) were exposed to different concentrations of primers (0-0.25 mg/ml) in the presence or absence of NAC, and the cytotoxicity was assessed by the MTT assay, while cell death was quantified by flow cytometry after propidium iodide staining. The increase in the induced ROS levels was detected by flow cytometry measuring the fluorescence of the oxidation-sensitive dye 2',7'-dichlorofluorescein diacetate (DCFH-DA). All materials decreased cell viability in a dose-related manner after a 24 h exposure period. Cytotoxicity of orthodontic primers based on concentrations which caused a 50% decrease in cell viability (TC₅₀) in HGF was ranked as follows (median values): Eagle Fluorsure (0.078 mg/ml)>Transbond XT (0.081 mg/ml)>Transbond MIP (0.128 mg/ml)>Ortho solo (0.130 mg/ml). Moreover, in HGF cells, all materials induced a dose-dependent increase in ROS levels compared to untreated cells. Incubation of HGF with NAC significantly reduced ROS production and decreased the cell damage and cytotoxicity caused by all materials tested (p<0.001). Our results suggested that hydrophilic primers were less cytotoxic than hydrophobic materials. Moreover, we demonstrated a major role of ROS in the induction of cell death since the antioxidant N-acetyl cysteine was able to prevent cell damage induced by all materials tested. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Cytotoxic, anti-cancer, and anti-microbial effects of different extracts obtained from Artemisia rupestris.

PubMed

Nokerbek, Shamshabanu; Sakipova, Zuriyadda; Chalupová, Marta; Nejezchlebová, Marcela; Hošek, Jan

2017-01-01

Artemisia rupestris is a part of traditional Kazakh folk medicine. Extracts obtained from this plant are used to treat various diseases, including cancer. This study evaluates the anti-microbial, cytotoxic, and anti-cancer effects of different extracts of the plant. Different extraction techniques were used and the resultant activities were compared. Extracts of A. rupestris were prepared from the flowers plus the leaves and from the stems. The antimicrobial activity against Candida albicans and Staphylococcus aureus was quantified. Cell lines L1210 and THP-1 were used to evaluate the cytotoxic potential of these extracts in vitro. The anti-cancer effect was tested using L1210-induced tumorgenesis in mouse model. The aqueous extract of stems was the most active against C. albicans, whereas the methanolic extract of flowers plus leaves especially inhibited the growth of S. aureus. The aqueous extracts were found to be non-cytotoxic for both cell lines, whereas the lipophilic extracts showed cytotoxic effects. The extract obtained from flowers plus leaves was more cytotoxic than that from stems. The tested extracts showed no anti-cancer potential. The results obtained testify to the relatively safe consumption of aqueous extracts of A. rupestris, but lipophilic extracts showed toxic effects and their consumption should be considered more carefully.Key words: L1210 cell line THP-1 cell line microwave-assisted extraction ultrasonic-assisted extraction Candida albicans Staphylococcus aureus.

Enhancement of phagocytosis and cytotoxicity in macrophages by tumor-derived IL-18 stimulation

PubMed Central

Henan, Xu; Toyota, Naoka; Yanjiang, Xing; Fujita, Yuuki; Zhijun, Huang; Touma, Maki; Qiong, Wu; Sugimoto, Kenkichi

2014-01-01

Inoculation of mice with the murine NFSA cell line caused the formation of large tumors with necrotic tumor cores. FACS analysis revealed accumulations of CD11b+ cells in the tumors. Microarray analysis indicated that the NFSA cells expressed a high level of the pro-inflammatory factor interleukin-18 (il-18), which is known to play a critical role in macrophages. However, little is known about the physiological function of IL-18-stimulated macrophages. Here, we provide direct evidence that IL-18 enhances the phagocytosis of RAW264 cells and peritoneal macrophages, accompanied by the increased expression of tumor necrosis factor (tnf-α), interleukin-6 (il-6) and inducible nitric oxide synthase (Nos2). IL-18-stimulated RAW264 cells showed an enhanced cytotoxicity to endothelial F-2 cells via direct cell-to-cell interaction and the secretion of soluble mediators. Taken together, our results demonstrate that tumor-derived IL-18 plays an important role in the phagocytosis of macrophages and that IL-18-stimulated macrophages may damage tumor endothelial cells. [BMB Reports 2014; 47(5): 286-291] PMID:24286318

Neutral sphingomyelinase 2 modulates cytotoxic effects of protopanaxadiol on different human cancer cells

PubMed Central

2013-01-01

Background Some of ginsenosides, root extracts from Panax ginseng, exert cytotoxicity against cancer cells through disruption of membrane subdomains called lipid rafts. Protopanaxadiol (PPD) exhibits the highest cytotoxic effect among 8 ginsenosides which we evaluated for anti-cancer activity. We investigated if PPD disrupts lipid rafts in its cytotoxic effects and also the possible mechanisms. Methods Eight ginsenosides were evaluated using different cancer cells and cell viability assays. The potent ginsenoside, PPD was investigated for its roles in lipid raft disruption and downstream pathways to apoptosis of cancer cells. Anti-cancer effects of PPD was also investigated in vivo using mouse xenograft model. Results PPD consistently exerts its potent cytotoxicity in 2 cell survival assays using 5 different cancer cell lines. PPD disrupts lipid rafts in different ways from methyl-β-cyclodextrin (MβCD) depleting cholesterol out of the subdomains, since lipid raft proteins were differentially modulated by the saponin. During disruption of lipid rafts, PPD activated neutral sphingomyelinase 2 (nSMase 2) hydrolyzing membrane sphingomyelins into pro-apoptotic intracellular ceramides. Furthermore, PPD demonstrated its anti-cancer activities against K562 tumor cells in mouse xenograft model, confirming its potential as an adjunct or chemotherapeutic agent by itself in vivo. Conclusions This study demonstrates that neutral sphingomyelinase 2 is responsible for the cytotoxicity of PPD through production of apoptotic ceramides from membrane sphingomyelins. Thus neutral sphingomyelinase 2 and its relevant mechanisms may potentially be employed in cancer chemotherapies. PMID:23889969

Transactivation of bad by vorinostat-induced acetylated p53 enhances doxorubicin-induced cytotoxicity in cervical cancer cells.

PubMed

Lee, Sook-Jeong; Hwang, Sung-Ook; Noh, Eun Joo; Kim, Dong-Uk; Nam, Miyoung; Kim, Jong Hyeok; Nam, Joo Hyun; Hoe, Kwang-Lae

2014-02-14

Vorinostat (VOR) has been reported to enhance the cytotoxic effects of doxorubicin (DOX) with fewer side effects because of the lower DOX dosage in breast cancer cells. In this study, we investigated the novel mechanism underlying the synergistic cytotoxic effects of VOR and DOX co-treatment in cervical cancer cells HeLa, CaSki and SiHa cells. Co-treatment with VOR and DOX at marginal doses led to the induction of apoptosis through caspase-3 activation, poly (ADP-ribose) polymerase cleavage and DNA micronuclei. Notably, the synergistic growth inhibition induced by the co-treatment was attributed to the upregulation of the pro-apoptotic protein Bad, as the silencing of Bad expression using small interfering RNA (siRNA) abolished the phenomenon. As siRNA against p53 did not result in an increase in acetylated p53 and the consequent upregulation of Bad, the observed Bad upregulation was mediated by acetylated p53. Moreover, a chromatin immunoprecipitation analysis showed that the co-treatment of HeLa cells with VOR and DOX increased the recruitment of acetylated p53 to the bad promoter, with consequent bad transactivation. Conversely, C33A cervical cancer cells containing mutant p53 co-treated with VOR and DOX did not exhibit Bad upregulation, acetylated p53 induction or consequent synergistic growth inhibition. Together, the synergistic growth inhibition of cervical cancer cell lines induced by co-treatment with VOR and DOX can be attributed to the upregulation of Bad, which is induced by acetylated p53. These results show for the first time that the acetylation of p53, rather than histones, is a mechanism for the synergistic growth inhibition induced by VOR and DOX co-treatments.

Melatonin sensitizes human cervical cancer HeLa cells to cisplatin-induced cytotoxicity and apoptosis: effects on oxidative stress and DNA fragmentation.

PubMed

Pariente, Roberto; Pariente, José A; Rodríguez, Ana B; Espino, Javier

2016-01-01

Melatonin has antitumor activity via several mechanisms including its antiproliferative and pro-apoptotic effects as well as its potent antioxidant actions, although recent evidence has indicated that melatonin may perform pro-oxidant actions in tumor cells. Therefore, melatonin may be useful in the treatment of tumors in association with chemotherapy drugs. This study was intended to evaluate the in vitro effect of melatonin on the cytotoxic and pro-apoptotic actions of various chemotherapeutic agents in cervical cancer HeLa cells. Herein, we found that both melatonin and three of the chemotherapeutic drugs tested, namely cisplatin (CIS), 5-fluorouracil (5-FU), and doxorubicin, induced a decrease in HeLa cell viability. Furthermore, melatonin significantly increased the cytotoxic effect of such chemotherapeutic agents. Consistently, costimulation of HeLa cells with any chemotherapeutic agent in the presence of melatonin further increased caspase-3 activation, particularly in CIS- and 5-FU-challenged cells. Likewise, concomitant treatments with melatonin and CIS significantly enhanced the ratio of cells entering mitochondrial apoptosis due to reactive oxygen species (ROS) overproduction, substantially augmented the population of apoptotic cells, and markedly enlarged DNA fragmentation compared to the treatments with CIS alone. Nonetheless, melatonin only displayed moderate chemosensitizing effects in 5-FU-stimulated HeLa cells, as suggested by slight increments in the percentage of cells stimulated for ROS production and in the proportion of early apoptotic cells compared to the treatments with 5-FU alone. In summary, our findings provided evidence that in vitro melatonin strongly enhances CIS-induced cytotoxicity and apoptosis in HeLa cells and, hence, the indoleamine could be potentially applied to cervical cancer treatment as a powerful synergistic agent. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cytotoxic and glycosaminoglycan priming activities of novel 4-anilinequinazoline β-D-xylosides.

PubMed

Wang, Jinpeng; Chang, Yajing; Dong, Xueyang; Zhang, Renshuai; Tang, Yang; Zhang, Meng; Yu, Rilei; Jiang, Tao; Zhang, Lijuan

2018-06-30

β-D-xylosides with cytotoxic aglycones have augmented cytotoxicity towards animal cells because β-D-xyloside-primed glycosaminoglycans further enhance the aglycone's cytotoxicity. In this study, we designed and synthesized different 4-anilinequinazoline β-D-xylosides and found that compounds 7-10 possessing 3-chloro-4-((3-fluorobenzyl)oxy)aniline group as in anticancer drug lapatinib also primed glycosaminoglycans and were highly cytotoxic to cancer cells. Copyright © 2018. Published by Elsevier Ltd.

Gemcitabine: Selective cytotoxicity, induction of inflammation and effects on urothelial function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Farr, Stefanie E; Chess-Williams, Russ; McDermott,

Intravesical gemcitabine has recently been introduced for the treatment of superficial bladder cancer and has a favourable efficacy and toxicity profile in comparison to mitomycin c (MMC), the most commonly used chemotherapeutic agent. The aim of this study was to assess the cytotoxic potency of gemcitabine in comparison to MMC in urothelial cell lines derived from non-malignant (UROtsa) and malignant (RT4 and T24) tissues to assess selectivity. Cells were treated with gemcitabine or mitomycin C at concentrations up to the clinical doses for 1 or 2 h respectively (clinical duration). Treatment combined with hyperthermia was also examined. Cell viability, ROSmore » formation, urothelial function (ATP, acetylcholine and PGE2 release) and secretion of inflammatory cytokines were assessed. Gemcitabine displayed a high cytotoxic selectivity for the two malignant cell lines (RT4, T24) compared to the non-malignant urothelial cells (UROtsa, proliferative and non-proliferative). In contrast, the cytotoxic effects of MMC were non-selective with equivalent potency in each of the cell lines. The cytotoxic effect of gemcitabine in the malignant cell lines was associated with an elevation in free radical formation and was significantly decreased in the presence of an equilibrative nucleoside transporter inhibitor. Transient changes in urothelial ATP and PGE{sub 2} release were observed, with significant increase in release of interleukin-6, interleukin-8 and interleukin-1β from urothelial cells treated with gemcitabine. The selectivity of gemcitabine for malignant urothelial cells may account for the less frequent adverse urological effects with comparison to other commonly used chemotherapeutic agents. - Highlights: • Intravesical gemcitabine has recently been introduced to treat bladder cancer. • Gemcitabine is selectively toxic for malignant urothelial cells. • Urothelial ATP, PGE{sub 2} and inflammatory cytokines were altered by gemcitabine. • Selectivity of

Cytotoxic effect of indigenously fabricated dental magnets for application in prosthodontics.

PubMed

Guttal, Satyabodh Shesharaj; Nadiger, Ramesh K; Shetty, Pravinkumar

2018-01-01

Dental magnets are used for retaining removable prostheses such as a removable partial denture, complete denture, and maxillofacial prosthesis. They provide good retention for the prostheses. However, the elements released from the magnets may be cytotoxic for the tissues. Therefore, it is necessary to evaluate their cytotoxic effect on cell lines. The aim of the study is to check the cytotoxic effect of indigenously fabricated dental magnets on animal cell lines. Neodymium-iron-boron (Nd-Fe-B) magnet was tested for cytotoxicity. The magnet was encased in a teflon cylinder. Magnets were placed in the well tissue-cultured plates together with a suspension containing NIH 3T3 mouse fibroblasts (5 × 10 5 cells/ml). After 3 days of incubation at 37°C, cell viability was determined by mean transit time (MTT) assay. Cells were subsequently dissolved in 100 μl dimethyl sulfoxide with gentle shaking for 2 h at room temperature followed by measurement of absorbance at 570 nm. Eight replicate wells were used at each point in each of four separate measurements. Measured absorbance values were directly used for calculating percent of viable cells remaining after the respective treatment. Data were analyzed statistically with significance level set at P < 0.05. The control group had highest absorbance reading for the MTT assay followed by test group. The lowest values were found with bare Nd-Fe-B magnets. One-way ANOVA test was performed for the data obtained. There was a statistical significant difference seen in the positive control (bare magnets, 44.96) and the test (teflon cased magnets, 96.90) group. More number of viable cells was visible in test group cells indicating that the indigenously fabricated dental magnet did not show any cytotoxicity.

Role of glycogen synthase kinase 3 beta (GSK3beta) in mediating the cytotoxic effects of the histone deacetylase inhibitor trichostatin A (TSA) in MCF-7 breast cancer cells.

PubMed

Alao, John P; Stavropoulou, Alexandra V; Lam, Eric W-F; Coombes, R Charles

2006-10-03

Histone deacetylase inhibitors (HDACIs) have been shown to induce apoptotic and autophagic cell death in vitro and in vivo. The molecular mechanisms that underlie these cytotoxic effects are not yet clearly understood. Recently, HDACIs were shown to induce Akt dephosphorylation by disrupting HDAC-protein phosphatase 1 (PP1) complexes. This disruption results in the increased association of PP1 with Akt, resulting in the dephosphorylation and consequent inactivation of the kinase. Akt enhances cellular survival through the phosphorylation-dependent inhibition of several pro-apoptotic proteins. Akt is an important negative regulator of GSK3beta, a kinase that has been shown to regulate apoptosis in response to various stimuli. In the present study, we investigated the role of GSK3beta in mediating the cytotoxic effects in MCF-7 breast cancer cells treated with trichostatin A (TSA), a prototype HDACI. We show that TSA induces Akt dephosphorylation in a PP1-dependent manner, resulting in activation of GSK3beta in MCF-7 cells. Similarly, knockdown of HDAC1 and-2 by small interfering RNA (siRNA) resulted in the dephosphorylation of Akt and GSK3beta. Selective inhibition of GSK3beta attenuated TSA induced cytotoxicity and resulted in enhanced proliferation following drug removal. Our findings identify GSK3beta as an important mediator of TSA-induced cytotoxicity in MCF-7 breast cancer cells.

In vitro cytotoxicity of maxillofacial silicone elastomers: effect of accelerated aging.

PubMed

Bal, Bilge Turhan; Yilmaz, Handan; Aydin, Cemal; Karakoca, Seçil; Yilmaz, Sükran

2009-04-01

The purpose of this in vitro study was to evaluate the cytotoxicity of three maxillofacial silicone elastomers at 24, 48, and 72 h on L-929 cells and to determine the effect of accelerated aging on the cytotoxicity of these silicone elastomers. Disc-shaped test samples of maxillofacial silicone elastomers (Cosmesil, Episil, Multisil) were fabricated according to manufacturers' instructions under aseptic conditions. Samples were then divided into three groups: (1) not aged; (2) aged for 150 h with an accelerated weathering tester; and (3) aged for 300 h. Then the samples were placed in Dulbecco's Modified Eagle Medium/Ham's F12 (DMEM/F12) for 24, 48, and 72 h. After the incubation periods, cytotoxicity of the extracts to cultured fibroblasts (L-929) was measured by MTT assay. The degree of cytotoxicity of each sample was determined according to the reference value represented by the cells with a control (culture without sample). Statistical significance was determined by repeated measurement ANOVA (p < 0.01) followed by Duncan's test (p < 0.05). All test materials in each group demonstrated high survival rates in MTT assay (Episil; 93.84%, Multisil; 88.30%, Cosmesil; 87.50%, respectively); however, in all groups, Episil material demonstrated significantly higher cell survival rate after each of the experimental incubation periods (p < 0.05). Accelerated aging for 150 and 300 h had no significant effect on the biocompatibility of maxillofacial silicone elastomers tested (p > 0.05).

Cytotoxicity and the effect of cationic peptide fragments against cariogenic bacteria under planktonic and biofilm conditions.

PubMed

Kreling, Paula Fernanda; Aida, Kelly Limi; Massunari, Loiane; Caiaffa, Karina Sampaio; Percinoto, Célio; Bedran, Telma Blanca Lombardo; Spolidorio, Denise Madalena Palomari; Abuna, Gabriel Flores; Cilli, Eduardo Maffud; Duque, Cristiane

2016-10-01

This study evaluated the cytotoxicity and effect of fragments derived from three oral cationic peptides (CP): LL-37, D6-17 and D1-23 against cariogenic bacteria under planktonic and biofilm conditions. For cytotoxicity analysis, two epithelial cell lines were used. The minimum inhibitory concentration and the minimal bactericidal concentration were determined for the CP fragments and the control (chlorhexidine-CHX) against cariogenic bacteria. The fractional inhibitory concentration was obtained for the combinations of CP fragments on Streptococcus mutans. Biofilm assays were conducted with the best antimicrobial CP fragment against S. mutans. The results indicated that D6-17 was not cytotoxic. D1-23, LL-37 and CHX were not cytotoxic in low concentrations. D1-23 presented the best bactericidal activity against S. mutans, S. mitis and S. salivarius. Combinations of CP fragments did not show a synergic effect. D1-23 presented a higher activity against S. mutans biofilm than CHX. It was concluded that D1-23 showed a substantial effect against cariogenic bacteria and low cytotoxicity.

The Effect of Ultrafine Process on the Dissolution, Antibacterial Activity, and Cytotoxicity of Coptidis rhizoma

PubMed Central

Jiang, Zhen-Yu; Deng, Hai-Ying; Yu, Zhi-Jun; Ni, Jun-Yan; Kang, Si-He

2016-01-01

Background: The dosage of herb ultrafine particle (UFP) depended on the increased level of its dissolution, toxicity, and efficacy. Objective: The dissolution, antibacterial activity, and cytotoxicity of Coptidis rhizoma (CR) UFP were compared with those of traditional decoction (TD). Materials and Methods: The dissolution of berberine (BBR) of CR TD and UFP was determined by high-performance liquid chromatography. The antibacterial activity of CR extract was assayed by plate-hole diffusion and broth dilution method; the inhibitory effect of rat serums against bacteria growth was evaluated after orally given CR UFP or TD extract. The cytotoxicity of CR extract was evaluated by 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay. Results: The dissolution amount of BBR from CR UFP increased 6–8-folds in comparison to TD at 2 min, the accumulative amount of BBR in both UFP and TD group increased in a time-dependent manner. The minimal inhibitory concentrations and minimal bactericidal concentrations of CR UFP extract decreased to 1/2~1/4 of those of TD extract. The inhibitory effect of rat serums against bacteria growth decreased time-dependently, and no statistical difference was observed between two groups at each time point. The 50% cytotoxic concentrations of UFP extract increased 1.66~1.97 fold than those of TD. Conclusions: The antibacterial activity and cytotoxicity of CR UFP increased in a dissolution-effect manner in vitro, the increased level of cytotoxicity was lower than that of antibacterial activity, and the inhibitory effect of rat serums containing drugs of UFP group did not improve. SUMMARY Ultrafine grinding process caused a rapid increase of BBR dissolution from CR.The antibacterial activity and cytotoxicity of UFP extract in vitro increased in a dissolution-effect manner, but the cytotoxicity increased lower than the antibacterial activity.The antibacterial activity of rat serums of UFP group did not improve in comparison to that

β4-integrin-mediated cytotoxic activity of AexU in human prostate cancer PC3 cells

PubMed Central

KUMANO, MASAFUMI; MIYAKE, HIDEAKI; ABOLGHAIT, SAID K.; BEHNSAWY, HOSNY M.; FUJISAWA, MASATO

2013-01-01

The present study aimed to characterize the cytotoxic activity of AexU, an effector-mediating type three secretion system (TTSS) of gram-negative bacteria, in human prostate cancer cells, focusing on the association with β4-integrin expression. The cytotoxic effects of AexU either alone or in combination with chemotherapeutic agents were evaluated using several human prostate cancer cell lines. Human prostate cancer PC3 cells, in which an expression vector containing siRNA targeting β4-integrin had been introduced, were established (PC3/sh-In), and the cytotoxic effects of AexU on the PC3/sh-In cells were compared with the PC3 cells that were transfected with a control vector (PC3/C). The expression levels of β4-integrin in the PC3 cells were markedly higher compared with those in the LNCaP or DU145 cells, and the cytotoxic effects of AexU in the PC3 cells were more pronounced compared with those in the LNCaP or DU145 cells. The sensitivity of the PC3 cells to docetaxel and cisplatin was significantly enhanced following treatment with AexU, resulting in a decrease in the IC50 of the two agents by ~90%. The cytotoxic effect of AexU in the PC3/C cells was more marked compared with that in the PC3/sh-In cells, and the phosphorylation of Akt in the PC3/C cells appeared to be significantly more inhibited by the treatment with AexU compared with the PC3/sh-In cells. In conclusion, treatment with AexU may be a useful therapeutic option for prostate cancer when β4-integrin is overexpressed. The treatment appears to exert its effects through growth inhibition and by enhancing the sensitivity of the cancer cells to chemotherapeutic agents. PMID:24179545

Cisplatin Induces a Mitochondrial-ROS Response That Contributes to Cytotoxicity Depending on Mitochondrial Redox Status and Bioenergetic Functions

PubMed Central

Marullo, Rossella; Werner, Erica; Degtyareva, Natalya; Moore, Bryn; Altavilla, Giuseppe; Ramalingam, Suresh S.; Doetsch, Paul W.

2013-01-01

Cisplatin is one of the most effective and widely used anticancer agents for the treatment of several types of tumors. The cytotoxic effect of cisplatin is thought to be mediated primarily by the generation of nuclear DNA adducts, which, if not repaired, cause cell death as a consequence of DNA replication and transcription blockage. However, the ability of cisplatin to induce nuclear DNA (nDNA) damage per se is not sufficient to explain its high degree of effectiveness nor the toxic effects exerted on normal, post-mitotic tissues. Oxidative damage has been observed in vivo following exposure to cisplatin in several tissues, suggesting a role for oxidative stress in the pathogenesis of cisplatin-induced dose-limiting toxicities. However, the mechanism of cisplatin-induced generation of ROS and their contribution to cisplatin cytotoxicity in normal and cancer cells is still poorly understood. By employing a panel of normal and cancer cell lines and the budding yeast Saccharomyces cerevisiae as model system, we show that exposure to cisplatin induces a mitochondrial-dependent ROS response that significantly enhances the cytotoxic effect caused by nDNA damage. ROS generation is independent of the amount of cisplatin-induced nDNA damage and occurs in mitochondria as a consequence of protein synthesis impairment. The contribution of cisplatin-induced mitochondrial dysfunction in determining its cytotoxic effect varies among cells and depends on mitochondrial redox status, mitochondrial DNA integrity and bioenergetic function. Thus, by manipulating these cellular parameters, we were able to enhance cisplatin cytotoxicity in cancer cells. This study provides a new mechanistic insight into cisplatin-induced cell killing and may lead to the design of novel therapeutic strategies to improve anticancer drug efficacy. PMID:24260552

Effect of strontium addition and chitosan concentration variation on cytotoxicity of chitosan-alginate-carbonate apatite based bone scaffold

NASA Astrophysics Data System (ADS)

Perkasa, Rilis Eka; Umniati, B. Sri; Sunendar, Bambang

2017-09-01

Bone scaffold is one of the most important component in bone tissue engineering. Basically, bone scaffold is a biocompatible structure designed to replace broken bone tissue temporarily. Unlike conventional bone replacements, an advanced bone scaffold should be bioactive (e.g: supporting bone growth) and biodegradable as new bone tissue grow, while retain its mechanical properties similarity with bone. It is also possible to add more bioactive substrates to bone scaffold to further support its performance. One of the substrate is strontium, an element that could improve the ability of the bone to repair itself. However, it must be noted that excessive consumption of strontium could lead to toxicity and diseases, such as osteomalacia and hypocalcemia. This research aimed to investigate the effect of strontium addition to the cytotoxic property of chitosan-alginate-carbonate apatite bone scaffold. The amount of strontium added to the bone scaffold was 5% molar of the carbonate apatite content. As a control, bone scaffold without stronsium (0% molar) were also made. The effect of chitosan concentration variation on the cytotoxicity were also observed, where the concentration varies on 1% and 3% w/v of chitosan solution. The results showed an optimum result on bone scaffold sample with 5% molar of strontium and 3% chitosan, where 87.67% cells in the performed MTS-Assay cytotoxicity testing survived. This showed that the use of up to 5% molar addition of strontium and 3% chitosan could enhance the survivability of the cell.

Cytotoxic, mutagenicity, and genotoxicity effects of guanylhydrazone derivatives.

PubMed

Pinhatti, Valéria Rodrigues; da Silva, Juliana; Martins, Tales Leandro Costa; Moura, Dinara Jaqueline; Rosa, Renato Moreira; Villela, Izabel; Stopiglia, Cheila Denise Ottonelli; da Silva Santos, Selma; Scroferneker, Maria Lúcia; Machado, Carlos Renato; Saffi, Jenifer; Henriques, João Antonio Pêgas

2016-08-01

Several studies have reported that guanylhydrazones display a variety of desirable biological properties, such as antihypertensive, antibacterial, and antimalarial behaviour. They furthermore promote anti-pneumocystosis and anti-trypanosomiasis, exhibit antitumor activity, and show significant cytotoxicity against cancer cell lines. In this work, we have evaluated the cytotoxicity, mutagenicity, and genotoxicity of two guanylhydrazones derivatives, (E)-2-[(2,3-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (2,3-DMeB) and (E)-2-[(3,4-dimethoxyphenyl) methylene] hydrazine carboxymidamide hydrochloride (3,4-DMeB), in different biological models. Both 2,3-DMeB and 3,4-DMeB induce weak cytotoxic and mutagenic effects in bacteria and yeast. The genotoxicity of these compounds was determined in a fibroblast cell line (V79) using alkaline comet assay, as well as a modified comet assay with bacterial enzymes formamidopyrimidine DNA-glycosylase (FPG) and endonuclease III (EndoIII). Both guanylhydrazone derivatives induced DNA damage. Treatment of V79 cells with EndoIII and FPG proteins demonstrated a significant effect of 2,3-DMeB and 3,4-DMeB with respect to oxidized bases. In addition, the derivatives induced a significant increase in the frequency of micronucleated cells at high doses. The antifungal and anti-trypanosomal properties of these guanylhydrazone derivatives were also evaluated, and the obtained results suggest that 2,3-DMeB is more effective than 3,4-DMeB. The biological activity of 2,3-DMeB and 3,4-DMeB may thus be related, at least in part, to their oxidative potential, as well as to their ability to interact with DNA. Considering the previously reported in vitro antitumor activity of guanylhydrazone derivatives in combination with the lack of acute toxicity and the fact that DNA damage is only observed at high doses should render both compounds good candidates for in vivo studies on antitumor activity. Copyright © 2016 Elsevier B

The Gα1-cAMP signaling pathway controls conidiation, development and secondary metabolism in the taxol-producing fungus Pestalotiopsis microspora.

PubMed

Yu, Xi; Liu, Heng; Niu, Xueliang; Akhberdi, Oren; Wei, Dongsheng; Wang, Dan; Zhu, Xudong

2017-10-01

G-protein-mediated signaling pathways regulate fungal morphogenesis, development and secondary metabolism. In this study, we report a gene, pgα1, that putatively encodes the α-subunit of a group I G protein in Pestalotiopsis microspora NK17, which is known to produce various secondary metabolites, including the antitumor drug taxol and pestalotiollide B (PB). Mutants of pgα1 showed retarded vegetative growth, aging of the mycelium, premature conidiation, deformed conidia, significantly increased melanin production, and a sharp decrease in PB production. The introduction of extra copies of pgα1 led to a different phenotype that was characterized by enhanced production of PB. qRT-PCR revealed that the expression of pks1, which encodes melanin polyketide synthase, an enzyme that is involved in 1, 8-dihydroxynaphthalene (DHN) melanin biosynthesis, was up regulated by 55-fold in the absence of pgα1. Changes in conidiation and PB production in pgα1 mutants were able to be restored by the addition of exogenous cAMP. The deficiencies of PB production and conidiation in Δpgα1 were not able to be rescued by deletion or overexpression of a previously reported histone deacetylase gene (hid1), suggesting that pgα1 is able to override the effect of hid1 on PB production and conidiation. Our results suggested that the G protein-cAMP pathway plays a critical role in vegetative growth as well as in asexual development of P. microspora. Copyright © 2017 Elsevier GmbH. All rights reserved.

Side effects of oxysterols: cytotoxicity, oxidation, inflammation, and phospholipidosis.

PubMed

Vejux, A; Malvitte, L; Lizard, G

2008-07-01

Oxysterols are 27-carbon atom molecules resulting from autoxidation or enzymatic oxidation of cholesterol. They are present in numerous foodstuffs and have been demonstrated to be present at increased levels in the plasma of patients with cardiovascular diseases and in atherosclerotic lesions. Thus, their role in lipid disorders is widely suspected, and they might also be involved in important degenerative diseases such as Alzheimer's disease, osteoporosis, and age-related macular degeneration. Since atherosclerosis is associated with the presence of apoptotic cells and with oxidative and inflammatory processes, the ability of some oxysterols, especially 7-ketocholesterol and 7beta-hydroxycholesterol, to trigger cell death, activate inflammation, and modulate lipid homeostasis is being extensively studied, especially in vitro. Thus, since there are a number of essential considerations regarding the physiological/pathophysiological functions and activities of the different oxysterols, it is important to determine their biological activities and identify their signaling pathways, when they are used either alone or as mixtures. Oxysterols may have cytotoxic, oxidative, and/or inflammatory effects, or none whatsoever. Moreover, a substantial accumulation of polar lipids in cytoplasmic multilamellar structures has been observed with cytotoxic oxysterols, suggesting that cytotoxic oxysterols are potent inducers of phospholipidosis. This basic knowledge about oxysterols contributes to a better understanding of the associated pathologies and may lead to new treatments and new drugs. Since oxysterols have a number of biological activities, and as oxysterol-induced cell death is assumed to take part in degenerative pathologies, the present review will focus on the cytotoxic activities of these compounds, the corresponding cell death signaling pathways, and associated events (oxidation, inflammation, and phospholipidosis).

Silver nanoparticles: Antimicrobial activity, cytotoxicity, and synergism with N-acetyl cysteine.

PubMed

Hamed, Selwan; Emara, Mohamed; Shawky, Riham M; El-Domany, Ramadan A; Youssef, Tareq

2017-08-01

The fast progression of nanotechnology has led to novel therapeutic interventions. Antimicrobial activities of silver nanoparticles (Ag NPs) were tested against standard ATCC strains of Staphylococcus aureus (ATCC 9144), Escherichia coli (O157:H7), Pseudomonas aeruginosa (ATCC 27853), and Candida albicans (ATCC 90028) in addition to 60 clinical isolates collected from cancer patients. Antimicrobial activity was tested by disk diffusion method and MIC values for Ag NPs alone and in combination with N-acetylcysteine (NAC) against tested pathogens were determined by broth microdilution method. Ag NPs showed a robust antimicrobial activity against all tested pathogens and NAC substantially enhanced the antimicrobial activity of Ag NPs against all tested pathogens. Synergism between Ag NPs and NAC has been confirmed by checkerboard assay. The effect of Ag NPs on tested pathogens was further scrutinized by Transmission Electron Microscope (TEM) which showed disruption of cell wall in both bacteria and fungi. Ag NPs abrogated the activity of respiratory chain dehydrogenase of all tested pathogens and released muramic acid content from S. aureus in culture. The cytotoxic effect of Ag NPs alone and in combination with NAC was examined using human HepG2 cells and this revealed no cytotoxicity at MIC values of Ag NPs and interestingly, NAC reduced the cytotoxic effect of Ag NPs at concentrations higher than their MIC values. Taken together, Ag NPs have robust antimicrobial activity and NAC substantially enhances their antimicrobial activities against MDR pathogens which would provide a novel safe, effective, and inexpensive therapeutic approach to control the prevalence of MDR pathogens. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Vorinostat Enhances Cytotoxicity of SN-38 and Temozolomide in Ewing Sarcoma Cells and Activates STAT3/AKT/MAPK Pathways

PubMed Central

Sampson, Valerie B.; Vetter, Nancy S.; Kamara, Davida F.; Collier, Anderson B.; Gresh, Renee C.; Kolb, E. Anders

2015-01-01

Histone deacetylase inhibitors (HDACi) have been evaluated in patients with Ewing sarcoma (EWS) but demonstrated limited activity. To better understand the potential for HDACi in EWS, we evaluated the combination of the HDACi vorinostat, with DNA damaging agents SN-38 (the active metabolite of irinotecan and topoisomerase 1 inhibitor) plus the alkylating agent temozolomide (ST). Drugs were evaluated in sequential and simultaneous combinations in two EWS cell lines. Results demonstrate that cell viability, DNA damage and reactive oxygen species (ROS) production are dependent on the sequence of drug administration. Enhanced cytotoxicity is exhibited in vitro in EWS cell lines treated with ST administered before vorinostat, which was modestly higher than concomitant treatment and superior to vorinostat administered before ST. Drug combinations downregulate cyclin D1 to induce G0/G1 arrest and promote apoptosis by cleavage of caspase-3 and PARP. When ST is administered before or concomitantly with vorinostat there is activation of STAT3, MAPK and the p53 pathway. In contrast, when vorinostat is administered before ST, there is DNA repair, increased AKT phosphorylation and reduced H2B acetylation. Inhibition of AKT using the small molecule inhibitor MK-2206 did not restore H2B acetylation. Combining ST with the dual ALK and IGF-1R inhibitor, AZD3463 simultaneously inhibited STAT3 and AKT to enhance the cytotoxic effects of ST and further reduce cell growth suggesting that STAT3 and AKT activation were in part mediated by ALK and IGF-1R signaling. In summary, potent antiproliferative and proapoptotic activity were demonstrated for ST induced DNA damage before or simultaneous with HDAC inhibition and cell death was mediated through the p53 pathway. These observations may aid in designing new protocols for treating pediatric patients with high-risk EWS. PMID:26571493

Cytotoxic effects of basic FGF and heparin binding EGF conjugated with cytotoxin saporin on vascular cell cultures.

PubMed

Chen, C; Li, J; Micko, C J; Pierce, G F; Cunningham, M R; Lumsden, A B

1998-02-15

Vascular smooth muscle cell (SMC) proliferation is an integral component of intimal lesion formation. In this study we compared the mitogenic effects of basic fibroblast growth factor (bFGF) and heparin binding epidermal growth factor (HBEGF) and the cytotoxic effects of bFGF and HBEGF conjugated with plant cytotoxin saporin (SAP) on vascular cell cultures. Human vascular SMCs and endothelial cells were cultured and FGF receptor-1 (FGFR-1) and EGF receptor (EGFR) expression were detected by immunohistochemical staining. Cells were grown in 24-well plates. Variable amounts of testing drugs (bFGF, HBEGF, SAP, bFGF-SAP, or HBEGF-SAP) were added to quadruplicate wells after 24 h. Cells without drugs were used as control. The total number of cells was counted at 72 h using a hemocytometer. The cultured human vascular SMCs and endothelial cells expressed both FGFR-1 and EGFR with predominant perinuclear localization. bFGF and HBEGF demonstrated equally potent mitogenic effects on SMC proliferation. SAP alone showed a limited cytotoxic effect on both SMCs and endothelial cells. bFGF had a more potent effect on endothelial cell proliferation than HBEGF. bFGF-SAP was equally cytotoxic for both SMCs and endothelial cells, while HBEGF-SAP had a more selectively cytotoxic effect on SMCs than on endothelial cells. These data suggest that the mitogenic effects of bFGF and HBEGF and the cytotoxic effects of bFGF-SAP and HBEGF-SAP may both be mediated by their corresponding growth factor receptors. Because of its selective cytotoxic effect on SMCs, HBEGF-SAP may become a more attractive agent for controlling intimal lesion formation.

Shape-dependent antibacterial effects of non-cytotoxic gold nanoparticles

PubMed Central

Penders, Jelle; Stolzoff, Michelle; Hickey, Daniel J; Andersson, Martin; Webster, Thomas J

2017-01-01

Gold nanoparticles (AuNPs) of various shapes (including spheres, stars and flowers), with similar dimensions, were synthesized and evaluated for their antibacterial effects toward Staphylococcus aureus, a bacterium responsible for numerous life-threatening infections worldwide. Optical growth curve measurements and Gompertz modeling showed significant AuNP shape- and concentration-dependent decreases in bacterial growth with increases in bacterial growth lag time. To evaluate prospective use in in vivo systems, the cytotoxicity of the same AuNPs was evaluated toward human dermal fibroblasts in vitro by 3-(4,5 dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) viability assays and confocal microscopy. No indication of any mammalian cell toxicity or morphological effects was found. Additionally, it was observed that the AuNPs were readily internalized in fibroblasts after 4 days of incubation. Most importantly, the results of the present study showed that gold nanoflowers in particular possessed the most promising non-cytotoxic mammalian cell behavior with the greatest shape-dependent antibacterial activity-promising properties for their future investigation in a wide range of anti-infection applications. PMID:28408817

Protective effects of melatonin-loaded lipid-core nanocapsules on paraquat-induced cytotoxicity and genotoxicity in a pulmonary cell line.

PubMed

Charão, Mariele F; Baierle, Marília; Gauer, Bruna; Goethel, Gabriela; Fracasso, Rafael; Paese, Karina; Brucker, Natália; Moro, Angela M; Bubols, Guilherme B; Dias, Bruna B; Matte, Ursula S; Guterres, Silvia S; Pohlmann, Adriana R; Garcia, Solange C

2015-06-01

Many acute poisonings lack effective and specific antidotes. Due to both intentional and accidental exposures, paraquat (PQ) causes thousands of deaths annually, especially by pulmonary fibrosis. Melatonin (Mel), when incorporated into lipid-core nanocapsules (Mel-LNC), has enhanced antioxidant properties. The effects of such a formulation have not yet been studied with respect to mitigation of PQ- induced cytotoxicity and DNA damage. Here, we have tested whether Mel-LNC can ameliorate PQ-induced toxicity in the A549 alveolar epithelial cell line. Physicochemical characterization of the formulations was performed. Cellular uptake was measured using nanocapsules marked with rhodamine B. Cell viability was determined by the MTT assay and DNA damage was assessed by the comet assay. The enzyme-modified comet assay with endonuclease III (Endo III) and formamidopyrimidine glycosylase (FPG) were used to investigate oxidative DNA damage. Incubation with culture medium for 24h did not alter the granulometric profile of Mel-LNC formulations. Following treatment (3 and 24h), red fluorescence was detected around the cell nucleus, indicating internalization of the formulation. Melatonin solution (Mel), Mel-LNC, and LNC did not have significant effects on cell viability or DNA damage. Pre-treatment with Mel-LNC enhanced cell viability and showed a remarkable reduction in % DNA in tail compared to the PQ group; this was not observed in cells pre-treated with Mel. PQ induces oxidative DNA damage detected with the enzyme-modified comet assay. Mel-LNC reduced this damage more effectively than did Mel. In summary, Mel-LNC is better than Mel at protecting A549 cells from the cytotoxic and genotoxic effects of PQ. Copyright © 2015 Elsevier B.V. All rights reserved.

Curcumin enhances the cytogenotoxic effect of etoposide in leukemia cells through induction of reactive oxygen species

PubMed Central

Papież, Monika A; Krzyściak, Wirginia; Szade, Krzysztof; Bukowska-Straková, Karolina; Kozakowska, Magdalena; Hajduk, Karolina; Bystrowska, Beata; Dulak, Jozef; Jozkowicz, Alicja

2016-01-01

Curcumin may exert a more selective cytotoxic effect in tumor cells with elevated levels of free radicals. Here, we investigated whether curcumin can modulate etoposide action in myeloid leukemia cells and in normal cells of hematopoietic origin. HL-60 cell line, normal myeloid progenitor cluster of differentiation (CD)-34+ cells, and granulocytes were incubated for 4 or 24 hours at different concentrations of curcumin and/or etoposide. Brown Norway rats with acute myeloid leukemia (BNML) were used to prove the influence of curcumin on etoposide action in vivo. Rats were treated with curcumin for 23 days and etoposide was administered for the final 3 days of the experiment. Curcumin synergistically potentiated the cytotoxic effect of etoposide, and it intensified apoptosis and phosphorylation of the histone H2AX induced by this cytostatic drug in leukemic HL-60 cells. In contrast, curcumin did not significantly modify etoposide-induced cytotoxicity and H2AX phosphorylation in normal CD34+ cells and granulocytes. Curcumin modified the cytotoxic action of etoposide in HL-60 cells through intensification of free radical production because preincubation with N-acetyl-l-cysteine (NAC) significantly reduced the cytotoxic effect of curcumin itself and a combination of two compounds. In contrast, NAC did not decrease the cytotoxic effect of etoposide. Thus, oxidative stress plays a greater role in the cytotoxic effect of curcumin than that of etoposide in HL-60 cells. In vitro results were confirmed in a BNML model. Pretreatment with curcumin enhanced the antileukemic activity of etoposide in BNML rats (1.57-fold tumor reduction versus etoposide alone; P<0.05) and induced apoptosis of BNML cells more efficiently than etoposide alone (1.54-fold change versus etoposide alone; P<0.05), but this treatment protected nonleukemic B-cells from apoptosis. Thus, curcumin can increase the antileukemic effect of etoposide through reactive oxygen species in sensitive myeloid leukemia

Enhanced sensitivity of A549 cells to the cytotoxic action of anticancer drugs via suppression of Nrf2 by procyanidins from Cinnamomi Cortex extract

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohnuma, Tomokazu; Matsumoto, Takashi; Itoi, Ayano

Highlights: {yields} We found a novel inhibitor of Nrf2 known as a chemoresistance factor. {yields} Overexpressed Nrf2 in lung cancer cells was suppressed by Cinnamomi Cortex extract. {yields} Cytotoxic action of anticancer drugs in cells treated with the extract was enhanced. {yields} Procyanidin tetramers and pentamers were active components in suppressing Nrf2. -- Abstract: Nuclear factor-E2-related factor 2 (Nrf2) is an important cytoprotective transcription factor because Nrf2-regulated enzymes play a key role in antioxidant and detoxification processes. Recent studies have reported that lung cancer cells overexpressing Nrf2 exhibit increased resistance to chemotherapy. Suppression of overexpressed Nrf2 is needed for amore » new therapeutic approach against lung cancers. In the present study, we found that Cinnamomi Cortex extract (CCE) has an ability to suppress Nrf2-regulated enzyme activity and Nrf2 expression in human lung cancer A549 cells with high Nrf2 activity. Moreover, we demonstrated that CCE significantly enhances sensitivity of A549 cells to the cytotoxic action of doxorubicin and etoposide as well as increasing the intracellular accumulation of both drugs. These results suggest that CCE might be an effective concomitant agent to reduce anticancer drug resistance derived from Nrf2 overexpression. Bioactivity-guided fractionation revealed that procyanidin tetramers and pentamers contained in CCE were active components in suppressing Nrf2.« less

Prevention of growth and metastasis of murine melanoma through enhanced natural-killer cytotoxicity by fatty acid-conjugate of protopanaxatriol.

PubMed

Hasegawa, Hideo; Suzuki, Ryuichi; Nagaoka, Takema; Tezuka, Yasuhiro; Kadota, Shigetoshi; Saiki, Ikuo

2002-07-01

Ginsenosides, the glycosides of Panax ginseng, are metabolized (deglycosylated) by intestinal bacteria after oral administration. 20(S)-Protopanaxatriol (M4) is the main bacterial metabolite of protopanaxatriol-type ginsenosides and mediates their antitumor effects. To clarify the mechanism of the M4-mediated antitumor effect, the antitumor activity and metabolism of M4 was examined, using the C57BL/6 mice implanted with B16-BL6 melanoma. The chronic oral administration of M4 inhibited the growth of B16-BL6 melanoma at the implanted site. Analyses using TLC, HPLC, MS and NMR suggest that orally administered M4 was absorbed from the small intestine into the mesenteric lymphatics followed by the rapid esterification of M4 with fatty acids and its accumulation in the tissues including the liver and lung. The administration of M4 prior to the intravenous injection of B16-BL6 cells abrogated the enhanced lung metastasis in the mice pretreated with 2-chloroadenosine more effectively than in those pretreated with anti-asialo GM1. The esterified M4 (EM4) did not directly affect tumor growth in vitro, whereas it stimulated splenic NK cells to become cytotoxic to tumor cells. These results indicate that the antitumor activity of M4 is based on the NK cell-mediated tumor lysis enhanced by EM4.

Fibrin matrices enhance the transplant and efficacy of cytotoxic stem cell therapy for post-surgical cancer

PubMed Central

Bagó, Juli R.; Pegna, Guillaume J.; Okolie, Onyi; Hingtgen, Shawn D.

2016-01-01

Tumor-homing cytotoxic stem cell (SC) therapy is a promising new approach for treating the incurable brain cancer glioblastoma (GBM). However, problems of retaining cytotoxic SCs within the post-surgical GBM resection cavity are likely to significantly limit the clinical utility of this strategy. Here, we describe a new fibrin-based transplant approach capable of increasing cytotoxic SC retention and persistence within the resection cavity, yet remaining permissive to tumoritropic migration. This fibrin-based transplant can effectively treat both solid and post-surgical human GBM in mice. Using our murine model of image-guided model of GBM resection, we discovered that suspending human mesenchymal stem cells (hMSCS) in a fibrin matrix increased initial retention in the surgical resection cavity 2-fold and prolonged persistence in the cavity 3-fold compared to conventional delivery strategies. Time-lapse motion analysis revealed that cytotoxic hMSCs in the fibrin matrix remain tumoritropic, rapidly migrating from the fibrin matrix to co-localize with cultured human GBM cells. We encapsulated hMSCs releasing the cytotoxic agent TRAIL (hMSC-sTR) in fibrin, and found hMSC-sTR/fibrin therapy reduced the viability of multiple 3-D human GBM spheroids and regressed established human GBM xenografts 3-fold in 11 days. Mimicking clinical therapy of surgically resected GBM, intra-cavity seeding of therapeutic hMSC-sTR encapsulated in fibrin reduced post-surgical GBM volumes 6-fold, increased time to recurrence 4-fold, and prolonged median survival from 15 to 36 days compared to control-treated animals. Fibrin-based SC therapy could represent a clinically compatible, viable treatment to suppress recurrence of post-surgical GBM and other lethal cancer types. PMID:26803410

Contrast-Enhanced Computed Tomography Evaluation of Hepatic Metastases in Breast Cancer Patients Before and After Cytotoxic Chemotherapy or Targeted Therapy.

PubMed

He, Hongying; Cai, Chunyan; Charnsangavej, Chusilp; Theriault, Richard L; Green, Marjorie; Quraishi, Mohammad A; Yang, Wei T

2015-11-01

To evaluate change in size vs computed tomography (CT) density of hepatic metastases in breast cancer patients before and after cytotoxic chemotherapy or targeted therapy. A database search in a single institution identified 48 breast cancer patients who had hepatic metastases treated with either cytotoxic chemotherapy alone or targeted therapy alone, and who had contrast-enhanced CT (CECT) scans of the abdomen at baseline and within 4 months of initiation of therapy in the past 10 years. Two radiologists retrospectively evaluated CT scans and identified up to 2 index lesions in each patient. The size (centimeters) of each lesion was measured according to Response Evaluation Criteria in Solid Tumors (RECIST) criteria, and CT density (Hounsfield units) was measured by drawing a region of interest around the margin of the entire lesion. The percent change in sum of lesion size and mean CT density on pre- and post-treatment scans was computed for each patient; results were compared within each treatment group. Thirty-nine patients with 68 lesions received cytotoxic chemotherapy only; 9 patients with 15 lesions received targeted therapy only. The mean percent changes in sum of lesion size and mean CT density were statistically significant within the cytotoxic chemotherapy group before and after treatment, but not significant in the targeted therapy group. The patients in the targeted therapy group tend to have better 2-year survival. The patients who survived at 2 years tend to have more decrease in tumour size in the cytotoxic chemotherapy group. Cytotoxic chemotherapy produced significant mean percent decrease in tumour size and mean CT density of hepatic metastases from breast cancer before and after treatment, whereas targeted therapy did not. Nonetheless, there is a trend that the patients in the targeted therapy group had better 2-year survival rate. This suggests that RECIST is potentially inadequate in evaluating tumour response in breast cancer liver

IL-2 activation of STAT5 enhances production of IL-10 from human cytotoxic regulatory T cells, HOZOT.

PubMed

Tsuji-Takayama, Kazue; Suzuki, Motoyuki; Yamamoto, Mayuko; Harashima, Akira; Okochi, Ayumi; Otani, Takeshi; Inoue, Toshiya; Sugimoto, Akira; Motoda, Ryuichi; Yamasaki, Fumiyuki; Nakamura, Shuji; Kibata, Masayoshi

2008-02-01

Interleukin (IL)-10 is an immunosuppressive cytokine produced by many cell types, including T cells. We previously reported that a novel type of regulatory T (Treg) cells, termed HOZOT, which possesses a FOXP3+CD4+CD8+CD25+ phenotype and dual suppressor/cytotoxic activities, produced high levels of IL-10. In this study, we examined the mechanisms of high IL-10 production by HOZOT, focusing on Janus activating kinase (JAK)/signal transducers and activators of transcription (STAT) signaling pathway. We prepared five different types of T cells, including HOZOT from human umbilical cord blood. Cytokine productions of IL-10, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha) were compared among these T cells after anti-CD3/CD28 antibody stimulation in the presence or absence of IL-2. Specific inhibitors for JAK/STAT, nuclear factor-kappaB (NF-kappaB), and nuclear factor for activated T cell (NFAT) were used to analyze signal transduction mechanisms. IL-10 production by HOZOTs was greatly enhanced by the addition of IL-2. Little or no enhancement of IFN-gamma and TNF-alpha production was observed under the same conditions. The enhancing effect of IL-2 was specific for both HOZOT and IL-10-secreting Treg cells. T helper type 2 cells, whose IL-10 production mechanisms involve GATA-3, failed to show IL-2-mediated enhancement of IL-10. Similar enhancing effects of IL-15 and IFN-alpha suggested a major role of JAK/STAT activation pathway for high IL-10 production. Further inhibitor experiments demonstrated that STAT5 rather than STAT3 was critically involved in this mechanism. Our results demonstrated that IL-2 selectively enhanced production of IL-10 in HOZOT primarily through activation of STAT5, which synergistically acts with NF-kappaB/NFAT activation, implying a novel regulatory mechanism of IL-10 production in Treg cells.

Cytotoxic effect of Reseda lutea L.: A case of forgotten remedy.

PubMed

Radulović, Niko S; Zlatković, Dragan B; Ilić-Tomić, Tatjana; Senerović, Lidija; Nikodinovic-Runic, Jasmina

2014-04-11

Reseda lutea L. (Resedaceae) or Wild Mignonette is a widely distributed plant species. Pliny the Elder (AD 23-AD 79), a Roman scholar and naturalist, reported the use of R. lutea for reducing tumors in his Historia naturalis. Accounts of the beneficial effects of R. lutea in tumor treatment could also be found in the works of later authors, such as Étienne François Geoffroy (1672-1731) and Samuel Frederick Gray (1766-1828). However, to date no in vivo or in vitro evidence exists in support of the alleged tumor healing properties of R. lutea. The composition of autolysates obtained from different organs (root, flower and fruit) of R. lutea was investigated by GC and GC-MS analyses and IR, 1D and 2D NMR spectroscopy. These analyses led to the discovery of a new compound isolated in pure form from the flower autolysate. Autolysates and their major constituents were submitted to MTT-dye reduction cytotoxic assay on human A375 (melanoma) and MRC5 (fibroblast) cell lines. Mechanism of the cytotoxic effects was studied by cell cycle analysis and Annexin V assay. Benzyl isothiocyanate and 2-(α-l-rhamnopyranosyloxy)benzyl isothiocyanate were identified as the major constituents of the root and flower autolysates, respectively (the later represents a new natural product). These compounds showed significant antiproliferative effects against both cell lines, which could also explain the observed high cytotoxic activity of the tested autolysates. Cell cycle analysis revealed apoptosis as the probable mechanism of cell death. Tumor healing properties attributed to R. lutea in the pre-modern texts were substantiated by the herein obtained results. Two isothiocyanates were found to be the major carriers of the observed activity. Although there was a relatively low differential effect of the plant metabolites on transformed and non-transformed cell lines, one can argue that the noted strong cytotoxicity provides first evidence that could explain the long forgotten use of this

The effect of heating temperature on cytotoxicity and α-mangostin yield: Mangosteen pericarp juice and mangosteen extract

NASA Astrophysics Data System (ADS)

Mulia, Kamarza; Hasanah, Fitria; Krisanti, Elsa A.

2018-03-01

The pericarp of mangosteen (Garcinia mangostana L.) contains bioactive xanthones, with α-mangostin being the major component, has been known to possess antitumor, antiviral, and other pharmacological activities. In this study, the effect of elevated temperature during the preparation step of fresh mangosteen pericarp juice and mangosteen extract, on their α-mangostin yield and cytotoxicities was investigated. The cytotoxicity activity of fresh juice and mangosteen extract was investigated using the brine shrimp test. Heating the fresh pericarp mangosteen in water at 65°C for 30 minutes prior to blending produced a juice with higher α-mangostin yield and cytotoxicity compared to the traditional way of blending the juice at room temperature. Increasing α-mangostin yield of 9%-w/w due to heating was also observed when mangosteen extract was heated at 65°C, consistent with the increased cytotoxicity in terms of LC50 value. It is concluded that the effect of temperature on α-mangostin yield was in line with the temperature effect on cytotoxicity activity in all samples of pericarp juice and mangosteen extract in ethyl acetate fraction.

Defense mechanism of heme oxygenase-1 against cytotoxic and receptor activator of nuclear factor-kappaB ligand inducing effects of hydrogen peroxide in human periodontal ligament cells.

PubMed

Pi, S-H; Kim, S-C; Kim, H-T; Lee, H-J; Lee, S-K; Kim, E-C

2007-08-01

Although induction of heme oxygenase-1 by H2O2 has been reported, the protective role of heme oxygenase-1 against the cytotoxic and osteoclastogenic effects of H2O2 have not been elucidated in human periodontal ligament cells. The aim of this work was to investigate the defense mechanism of heme oxygenase-1 on H2O2-induced cytotoxicity and to analyze the expression of receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin as markers for osteoclast differentiation in periodontal ligament cells. Using human periodontal ligament cells, cytotoxicity was measured by the 3,4,5-dimethylthiazol-2-yl-2,5-diphenyl tetrazolium bromide (MTT) assay, and expression of heme oxygenase-1, RANKL, and osteoprotegerin mRNA was determined by reverse transcription-polymerase chain reaction. H2O2 produced a cytotoxic effect by reducing the cell viability and enhancing the expression of heme oxygenase-1 and RANKL mRNAs in a concentration- and time-dependent manner. Additional experiments revealed that heme oxygenase-1 inducer (hemin), a membrane-permeable cGMP analog (8-bromo-cGMP), carbon monoxide, extracellular signal-regulated kinase, p38 mitogen-activated protein kinase inhibitor, protein kinase inhibitor (KT5823), and nuclear factor-kappaB inhibitor (pyrrolidine dithiocarbamate) also blocked the effects of H2O2 on cell viability and RANKL mRNA expression in periodontal ligament cells. These data suggest that heme oxygenase-1 induction plays a protective role in periodontal ligament cells against the cytotoxic and RANKL-inducing effects of H2O2, through multiple signaling pathways.

Evaluation of scopadulciol-related molecules for their stimulatory effect on the cytotoxicity of acyclovir and ganciclovir against Herpes simplex virus type 1 thymidine kinase gene-transfected HeLa cells.

PubMed

Hayashi, Kyoko; Rahman, S M Abdur; Ohno, Hiroaki; Tanaka, Tetsuaki; Toyooka, Naoki; Nemoto, Hideo; Hayashi, Toshimitsu

2004-08-01

Herpes simplex virus type 1 thymidine kinase (HSV TK) is involved in both antiherpetic therapy and cancer gene therapy with acyclovir (ACV) and ganciclovir (GCV). Enhanced sensitivity to these drugs is advantageous in their clinical use. In the present study, scopadulciol (SDC) and its related compounds were evaluated for their stimulatory effect on the cytotoxicity of ACV and GCV by determination of selective toxicities against HSV TK-expressing HeLa cells. Although SDC remarkably potenciated the cytotoxicity of ACV and GCV, the other tested compounds showed only weak selectivity, except for compound 34.

Sulforaphane synergistically enhances the cytotoxicity of arsenic trioxide in multiple myeloma cells via stress-mediated pathways

PubMed Central

DOUDICAN, NICOLE A.; WEN, SHIH YA; MAZUMDER, AMITABHA; ORLOW, SETH J.

2012-01-01

Persistent paraprotein production in plasma cells necessitates a highly developed rough endoplasmic reticulum (ER) that is unusually susceptible to perturbations in protein synthesis. This biology is believed to account for the exquisite sensitivity of multiple myeloma (MM) to the proteasomal inhibitor bortezomib (BTZ). Despite remarkable response rates to BTZ in MM, BTZ carries the potential for serious side-effects and development of resistance. We, therefore, sought to identify therapeutic combinations that effectively disrupt proteostasis in order to provide new potential treatments for MM. We found that sulforaphane, a dietary isothiocyanate found in cruciferous vegetables, inhibits TNFα-induced Iκβ proteasomal degradation in a manner similar to BTZ. Like BTZ, sulforaphane synergistically enhances the cytotoxicity of arsenic trioxide (ATO), an agent with clinical activity in MM. ATO and sulforaphane co-treatment augmented apoptotic induction as demonstrated by cleavage of caspase-3, -4 and PARP. The enhanced apoptotic response was dependent upon production of reactive oxygen species (ROS) as demonstrated by glutathione depletion and partial inhibition of the apoptotic cascade after pretreatment with the radical scavenger N-acetyl-cysteine (NAC). Combination treatment resulted in enhanced ER stress signaling and activation of the unfolded protein response (UPR), indicative of perturbation of proteostasis. Specifically, combination treatment caused elevated expression of the molecular chaperone HSP90 (heat shock protein 90) along with increased PERK (protein kinase RNA-like endoplasmic reticulum kinase) and eIF2α phosphorylation and XBP1 (X-box binding protein 1) splicing, key indicators of UPR activation. Moreover, increased splicing of XBP1 was apparent upon combination treatment compared to treatment with either agent alone. Sulforaphane in combination with ATO effectively disrupts protein homeostasis through ROS generation and induction of ER stress to

Cytotoxic effects of pyrrolidine dithiocarbamate in small-cell lung cancer cells, alone and in combination with cisplatin.

PubMed

Tahata, Shinichi; Yuan, Bo; Kikuchi, Hidetomo; Takagi, Norio; Hirano, Toshihiko; Toyoda, Hiroo

2014-10-01

The cytocidal effect of pyrrolidine dithiocarbamate (PDTC) was investigated by focusing on cell viability, cell cycle arrest and apoptosis induction in small-cell lung cancer (SCLC) cell lines (NCI-H196 and NCI-H889). PDTC exhibited a much stronger dose-dependent cytotoxic activity against NCI-H196 compared to NCI-H889, while no such activity was observed in normal human embryonal lung fibroblast MRC-5 cells. Cell cycle arrest in S phase paralleled with suppression of c-myc expression without accompanying DNA fragmentation was observed in NCI-H196 cells. A transient increase in the intracellular ROS accompanied with an alteration of expression of oxidative stress-related genes was also confirmed in NCI-H196 cells. Furthermore, the addition of N-acetyl-l-cysteine (NAC), a free radical scavenger, not only abolished PDTC-trigger alterations of expression of these oxidative-related genes, but also almost completely abrogated PDTC-induced reduction in cell viability and morphological changes associated with cell damage. These results thus suggest that PDTC-induced cytotoxicity is attributed to its pro-oxidant activity. PDTC-induced cytotoxicity was further enhanced by CuCl2, however, abolished by bathocuproine disulfonate (BCPS), a non-permeable copper-specific chelator, supporting the plausibility that accumulation of intracellular Cu plays an important role in the cytotoxicity. Importantly, we demonstrated for the first time that PDTC downregulated the expression of ATP7A, known to be responsible for Cu efflux, but did not affect the expression of CTR1, known as a copper uptake transporter. Intriguingly, combination of much lower dose of cisplatin (5 µM) and non-toxic dose of PDTC (0.1 µM) synergistically induced a significant cytotoxicity in NCI-H196 cells. Given that ATP7A plays a critical role in the resistance of platinum-drug (such as cisplatin) representing a first-line treatment for SCLC, PDTC could be a promising candidate of adjunct therapeutic reagent

Mapping of binding epitopes of a human decay-accelerating factor monoclonal antibody capable of enhancing rituximab-mediated complement-dependent cytotoxicity.

PubMed

Guo, Bo; Ma, Zheng-wei; Li, Hua; Xu, Gui-lian; Zheng, Ping; Zhu, Bo; Wu, Yu-Zhang; Zou, Qiang

2008-08-01

Complement-dependent cytotoxicity (CDC) is thought to be one of the most important mechanisms of action of therapeutic monoclonal antibodies (mAbs). The decay-accelerating factor (DAF) overexpressed in certain tumors limits the CDC effect of the therapeutic anticancer antibodies. The use of DAF blocking antibodies targeted specifically at cancer cells in combination with immunotherapeutic mAbs of cancer may improve the therapeutic effect in cancer patients. In this study, the lysis of Raji cells mediated by CDC was determined after blocking DAF function by anti-DAF polyclonal antibody and 3 mAbs (DG3, DG9, DA11) prepared in our laboratory, respectively, in the presence of the anti-CD20 chimeric mAb rituximab. The binding domains of the three anti-DAF mAbs were identified using yeast surface display technique, and the mimic epitopes of mAb DG3 were screened from a random phage-display nonapeptide library. The results showed that blocking DAF function by anti-DAF polyclonal antibody enhanced complement-mediated killing of Raji cells. Among the 3 mAbs against DAF, only DG3 was found to be able to remarkably enhance the CDC effect of the therapeutic mAb rituximab. DG3 bound to the third short consensus repeat (SCR) of DAF. Binding of DG3 to immobilized DAF was inhibited by mimic epitope peptides screened from the peptide library. Our results suggest that a higher level of DAF expressed by certain tumor cells is significant to abolish the CDC effect of therapeutic anticancer antibodies, and mAbs binding to SCR3 can enhance the complement-mediated killing of Raji cells. It is of significance to identify the DAF epitopes required in inhibiting CDC not only for better understanding of the relationship between the structure and function of DAF, but also for designing and developing anti-DAF mAbs capable of enhancing CDC.

BTK inhibitor ibrutinib is cytotoxic to myeloma and potently enhances bortezomib and lenalidomide activities through NF-κB.

PubMed

Rushworth, Stuart A; Bowles, Kristian M; Barrera, Lawrence N; Murray, Megan Y; Zaitseva, Lyubov; MacEwan, David J

2013-01-01

Ibrutinib (previously known as PCI-32765) has recently shown encouraging clinical activity in chronic lymphocytic leukaemia (CLL) effecting cell death through inhibition of Bruton's tyrosine kinase (BTK). In this study we report for the first time that ibrutinib is cytotoxic to malignant plasma cells from patients with multiple myeloma (MM) and furthermore that treatment with ibrutinib significantly augments the cytotoxic activity of bortezomib and lenalidomide chemotherapies. We describe that the cytotoxicity of ibrutinib in MM is mediated via an inhibitory effect on the nuclear factor-κB (NF-κB) pathway. Specifically, ibrutinib blocks the phosphorylation of serine-536 of the p65 subunit of NF-κB, preventing its nuclear translocation, resulting in down-regulation of anti-apoptotic proteins Bcl-xL, FLIP(L) and survivin and culminating in caspase-mediated apoptosis within the malignant plasma cells. Taken together these data provide a platform for clinical trials of ibrutinib in myeloma and a rationale for its use in combination therapy, particularly with bortezomib. Copyright © 2012 Elsevier Inc. All rights reserved.

Paracellular permeation-enhancing effect of AT1002 C-terminal amidation in nasal delivery

PubMed Central

Song, Keon-Hyoung; Kim, Sang-Bum; Shim, Chang-Koo; Chung, Suk-Jae; Kim, Dae-Duk; Rhee, Sang-Ki; Choi, Guang J; Kim, Chul-Hyun; Kim, Kiyoung

2015-01-01

Background The identification of permeation enhancers has gained interest in the development of drug delivery systems. A six-mer peptide, H-FCIGRL-OH (AT1002), is a tight junction modulator with promising permeation-enhancing activity. AT1002 enhances the transport of molecular weight markers or agents with low bioavailability with no cytotoxicity. However, AT1002 is not stable in neutral pH or after incubation under physiological conditions, which is necessary to fully uncover its permeation-enhancing effect. Thus, we increased the stability or mitigated the instability of AT1002 by modifying its terminal amino acids and evaluated its subsequent biological activity. Methods C-terminal-amidated (FCIGRL-NH2, Pep1) and N-terminal-acetylated (Ac-FCIGRL, Pep2) peptides were analyzed by liquid chromatography–mass spectrometry. We further assessed cytotoxicity on cell monolayers, as well as the permeation-enhancing activity following nasal administration of the paracellular marker mannitol. Results Pep1 was nontoxic to cell monolayers and showed a relatively low decrease in peak area compared to AT1002. In addition, administration of mannitol with Pep1 resulted in significant increases in the area under the plasma concentration–time curve and peak plasma concentration at 3.63-fold and 2.68-fold, respectively, compared to mannitol alone. In contrast, no increase in mannitol concentration was shown with mannitol/AT1002 or mannitol/Pep2 compared to the control. Thus, Pep1 increased the stability or possibly reduced the instability of AT1002, which resulted in an increased permeation-enhancing effect of AT1002. Conclusion These results suggest the potential usefulness of C-terminal-amidated AT1002 in enhancing nasal drug delivery, which may lead to the development of a practical drug delivery technology for drugs with low bioavailability. PMID:25848218

Increased betulinic acid induced cytotoxicity and radiosensitivity in glioma cells under hypoxic conditions.

PubMed

Bache, Matthias; Zschornak, Martin P; Passin, Sarina; Kessler, Jacqueline; Wichmann, Henri; Kappler, Matthias; Paschke, Reinhard; Kaluđerović, Goran N; Kommera, Harish; Taubert, Helge; Vordermark, Dirk

2011-09-09

Betulinic acid (BA) is a novel antineoplastic agent under evaluation for tumor therapy. Because of the selective cytotoxic effects of BA in tumor cells (including gliomas), the combination of this agent with conservative therapies (such as radiotherapy and chemotherapy) may be useful. Previously, the combination of BA with irradiation under hypoxic conditions had never been studied. In this study, the effects of 3 to 30 μM BA on cytotoxicity, migration, the protein expression of PARP, survivin and HIF-1α, as well as radiosensitivity under normoxic and hypoxic conditions were analyzed in the human malignant glioma cell lines U251MG and U343MG. Cytotoxicity and radiosensitivity were analyzed with clonogenic survival assays, migration was analyzed with Boyden chamber assays (or scratch assays) and protein expression was examined with Western blot analyses. Under normoxic conditions, a half maximal inhibitory concentration (IC50) of 23 μM was observed in U251MG cells and 24 μM was observed in U343MG cells. Under hypoxic conditions, 10 μM or 15 μM of BA showed a significantly increased cytotoxicity in U251MG cells (p = 0.004 and p = 0.01, respectively) and U343MG cells (p < 0.05 and p = 0.01, respectively). The combination of BA with radiotherapy resulted in an additive effect in the U343MG cell line under normoxic and hypoxic conditions. Weak radiation enhancement was observed in U251MG cell line after treatment with BA under normoxic conditions. Furthermore, under hypoxic conditions, the incubation with BA resulted in increased radiation enhancement. The enhancement factor, at an irradiation dose of 15 Gy after treatment with 10 or 15 μM BA, was 2.20 (p = 0.02) and 4.50 (p = 0.03), respectively. Incubation with BA led to decreased cell migration, cleavage of PARP and decreased expression levels of survivin in both cell lines. Additionally, BA treatment resulted in a reduction of HIF-1α protein under hypoxic conditions. Our results suggest that BA is capable of

MK-2206 induces apoptosis of AML cells and enhances the cytotoxicity of cytarabine.

PubMed

Lu, Jeng-Wei; Lin, Yu-Min; Lai, Yen-Ling; Chen, Chien-Yuan; Hu, Chung-Yi; Tien, Hwei-Fang; Ou, Da-Liang; Lin, Liang-In

2015-07-01

Genetic alterations in the PI3K/AKT cascade have been linked to various human cancers including acute myeloid leukemia (AML) and have emerged to be promising targets for treatment. In this study, we explored the molecular mechanism and clinical implication of a specific allosteric AKT inhibitor, MK-2206, in the treatment of AML. Four leukemia cell lines, MV-4-11, MOLM-13, OCI/AML3, and U937, were used. Apoptosis and cell cycle distribution were determined by flow cytometry analysis. Expression of anti-apoptotic protein family and glycogen synthase kinase 3β (GSK3β) signaling was determined by western blotting. Drug combination effects of MK-2206 with cytarabine were evaluated by cell proliferation assay, and the combination index values were calculated by CompuSyn software. MK-2206 had no effect on normal peripheral blood mononuclear cells, but induced G1-phase arrest and apoptosis in leukemia cells. Among anti-apoptotic Bcl-2 family members, only myeloid cell leukemia-1 (Mcl-1) was significantly suppressed. Mcl-1 suppression by MK-2206 was closely associated with decreased GSK3β phosphorylation at Ser9, an event leads to GSK3β activation. Furthermore, the effect of MK-2206 on Mcl-1 downregulation was abolished by GSK3β inhibitor, lithium chloride and proteasome inhibitor, MG-132, suggesting that MK-2206 acted through a GSK3β-mediated, proteasome-dependent protein degradation. In addition, co-administration of MK-2206 with cytarabine could enhance the cytotoxic efficacy of cytarabine in leukemia cell lines. In conclusion, we have demonstrated that MK-2206 is an active agent in AML and its efficacy as in combination with cytarabine is implicated.

Plasma stable, pH-sensitive non-ionic surfactant vesicles simultaneously enhance antiproliferative effect and selectivity of Sirolimus.

PubMed

Ghanbarzadeh, Saeed; Khorrami, Arash; Pourmoazzen, Zhaleh; Arami, Sanam

2015-05-01

The purpose of the present investigation was to prepare a plasma stable, pH-sensitive niosomal formulation to enhance Sirolimus efficacy and selectivity. pH-sensitive niosomal formulations bearing PEG-Poly (monomethyl itaconate)-CholC6 (PEG-PMMI-CholC6) copolymers and cholesteryl hemisuccinate (CHEMS) were prepared by a modified ethanol injection method and characterized with regard to pH-responsiveness and stability in human serum. The ability of pH-sensitive niosomes to enhance the Sirolimus cytotoxicity was evaluated in vitro using human erythromyeloblastoid leukemia cell line (K562) and compared with cytotoxicity effect on human umbilical vein endothelial cells (HUVEC). This study showed that both formulations can be rendered pH-sensitive property and were found to rapidly release their contents under mildly acidic conditions. However, the CHEMS-based niosomes lost their pH-sensitivity after incubation in plasma, whereas, PEG-PMMI-CholC6 niosomes preserved their ability to respond to pH change. Sirolimus encapsulated in pH-sensitive niosomes exhibited a higher cytotoxicity than the control conventional formulation on K562 cell line. On the other hand, both pH-sensitive niosomes showed lower antiproliferative effect on HUVEC cells. Plasma stable, pH-sensitive PEG-PMMI-CholC6-based niosomes can improve the in vitro efficiency and also reduce the side effects of Sirolimus.

Isoprenoid-substituted flavonoids from wood of Artocarpus heterophyllus on B16 melanoma cells: cytotoxicity and structural criteria.

PubMed

Arung, Enos Tangke; Yoshikawa, Keisuke; Shimizu, Kuniyoshi; Kondo, Ryuichiro

2010-03-01

As a result of cytotoxicity-guided fractionation, nine flavonoids, artocarpin (1), cudraflavone C (2), 6-prenylapigenin (3), kuwanon C (4), norartocarpin (5), albanin A (6), cudraflavone B (7), brosimone I (8) and artocarpanone (9) were identified from the methanol extract of the wood of Artocarpus heterophyllus, known commonly as Nangka in Indonesia. A structure-activity investigation of the effect of these isolated compounds (1-9) and structurally related compounds on B16 melanoma cells indicated that isoprenoid moiety substitutions in flavonoids enhance their cytotoxicity, and that the position of attachment and the number of isoprenoid-substituent moieties per molecule influence flavonoid cytotoxicity. 2009 Elsevier B.V. All rights reserved.

Mechanisms of Dihydroartemisinin and Dihydroartemisinin/Holotransferrin Cytotoxicity in T-Cell Lymphoma Cells

PubMed Central

Zhao, Xindong; Zhao, Chunting; Zhao, Hongguo; Huo, Lanfen

2015-01-01

The validated therapeutic effects of dihydroartemisinin (DHA) in solid tumors have encouraged us to explore its potential in treating T-cell lymphoma. We found that Jurkat cells (a T-cell lyphoma cell line) were sensitive to DHA treatment with a IC50 of dihydroartemisinin. The cytotoxic effect of DHA in Jurkat cells showed a dose- and time- dependent manner. Interestingly, the cytotoxic effect of DHA was further enhanced by holotransferrin (HTF) due to the high expression of transferrin receptors in T-cell lymphoma. Mechanistically, DHA significantly increased the production of intracellular reactive oxygen species, which led to cell cycle arrest and apoptosis. The DHA treatment also inhibited the expression of protumorgenic factors including VEGF and telomerase catalytic subunit. Our results have proved the therapeutic effect of DHA in T-cell lymphoma. Especially in combination with HTF, DHA may provide a novel efficient approach in combating the deadly disease. PMID:26502166

Effect of PEG molecular weight on stability, T₂ contrast, cytotoxicity, and cellular uptake of superparamagnetic iron oxide nanoparticles (SPIONs).

PubMed

Park, Yoonjee C; Smith, Jared B; Pham, Tuan; Whitaker, Ragnhild D; Sucato, Christopher A; Hamilton, James A; Bartolak-Suki, Elizabeth; Wong, Joyce Y

2014-07-01

Superparamagnetic iron oxide nanoparticles (SPIONs) are currently unavailable as MRI contrast agents for detecting atherosclerosis in the clinical setting because of either low signal enhancement or safety concerns. Therefore, a new generation of SPIONs with increased circulation time, enhanced image contrast, and less cytotoxicity is essential. In this study, monodisperse SPIONs were synthesized and coated with polyethylene glycol (PEG) of varying molecular weights. The resulting PEGylated SPIONs were characterized, and their interactions with vascular smooth muscle cells (VSMCs) were examined. SPIONs were tested at different concentrations (100 and 500 ppm Fe) for stability, T2 contrast, cytotoxicity, and cellular uptake to determine an optimal formulation for in vivo use. We found that at 100 ppm Fe, the PEG 2K SPIONs showed adequate stability and magnetic contrast, and exhibited the least cytotoxicity and nonspecific cellular uptake. An increase in cell viability was observed when the SPION-treated cells were washed with PBS after 1h incubation compared to 5 and 24h incubation without washing. Our investigation provides insight into the potential safe application of SPIONs in the clinic. Copyright © 2014 Elsevier B.V. All rights reserved.

Glycovariant anti-CD37 monospecific protein therapeutic exhibits enhanced effector cell-mediated cytotoxicity against chronic and acute B cell malignancies

PubMed Central

Rafiq, Sarwish; Siadak, Anthony; Butchar, Jonathan P.; Cheney, Carolyn; Lozanski, Gerard; Jacob, Naduparambil K.; Lapalombella, Rosa; McGourty, Jackie; Moledor, Meghan; Lowe, Richard; Setter, Ben; Jones, Jeffrey; Flynn, Joseph M.; Andritsos, Leslie; Devine, Steven; Mo, Xiaokui; Jarjoura, David; Tridandapani, Susheela; Algate, Paul; Byrd, John C.; Muthusamy, Natarajan

2013-01-01

TRU-016 is a SMIPTM (monospecific protein therapeutic) molecule against the tetraspanin transmembrane family protein CD37 that is currently in Phase 2 trials in Chronic Lymphocytic Leukemia (CLL) and Non-Hodgkin Lymphoma (NHL). In an attempt to enhance the ADCC function of SMIP-016, the chimeric version of TRU-016, SMIP-016GV was engineered with a modification in a glycosylation site in the Fc domain. The wild-type and glycovariant SMIP proteins mediate comparable Type I antibody-like direct cytotoxicity in the presence of anti-human Fc crosslinker and show a similar tyrosine phosphorylation pattern post-treatment. However, NK cells stimulated with the SMIP-016GV exhibit enhanced activation and release 3-fold more interferon-γ compared with SMIP-016. SMIP-016GV shows enhanced ADCC function against cells expressing CD37 with NK cell effectors derived from both normal and CLL-affected individuals. Enhanced ADCC is observed against CLL cells and is sustained at concentrations of SMIP-016GV as low at 5E−6 µg/mL on cells expressing minimal CD37 antigen. In support of the biological relevance of this, SMIP-016GV mediates effective ADCC against primary acute lymphoblastic leukemia (ALL) cells with low surface expression of CD37. Collectively, these data suggest potential use of the novel therapeutic agent SMIP-016GV with enhanced effector function for B cell malignancies, including CLL and ALL therapy. PMID:23883821

Effects of asarinin on dopamine biosynthesis and 6-hydroxydopamine-induced cytotoxicity in PC12 cells.

PubMed

Park, Hyun Jin; Lee, Kyung Sook; Zhao, Ting Ting; Lee, Kyung Eun; Lee, Myung Koo

2017-05-01

This study investigated the effects of asarinin on dopamine biosynthesis and 6-hydroxydopamine (6-OHDA)-induced cytotoxicity in rat adrenal pheochromocytoma (PC12) cells. Treatment with asarinin (25-50 μM) increased intracellular dopamine levels and enhanced L-DOPA-induced increases in dopamine levels. Asarinin (25 μM) induced cyclic AMP-dependent protein kinase A (PKA) signaling, leading to increased cyclic AMP-response element binding protein (CREB) and tyrosine hydroxylase (TH) phosphorylation, which in turn stimulated dopamine production. Asarinin (25 μM) also activated transient phosphorylation of extracellular signal-regulated kinase (ERK1/2) and Bad phosphorylation at Ser 112, both of which have been shown to promote cell survival. In contrast, asarinin (25 μM) inhibited sustained ERK1/2, Bax, c-Jun N-terminal kinase (JNK1/2) and p38 mitogen-activated protein kinase (p38MAPK) phosphorylation and caspase-3 activity, which were induced by 6-OHDA (100 μM). These results suggest that asarinin induces dopamine biosynthesis via activation of the PKA-CREB-TH system and protects against 6-OHDA-induced cytotoxicity by inhibiting the sustained activation of the ERK-p38MAPK-JNK1/2-caspase-3 system in PC12 cells.

Duration and mechanisms of the increased natural cytotoxicity seen after chronic voluntary exercise in rats.

PubMed

Jonsdottir, I H; Johansson, C; Asea, A; Johansson, P; Hellstrand, K; Thorén, P; Hoffmann, P

1997-08-01

We have recently shown that in vivo natural cytotoxicity is enhanced after chronic exercise in spontaneously hypertensive rats (SHRs). In the present report, we have studied the duration of this augmentation and some possible mechanisms involved. Exercise consisted of voluntary running for 4-5 weeks, with the running distance ranging from 2.7-15.6 km day(-1) during the last week of running. In vivo cytotoxicity was measured as clearance of injected 51Cr-labelled YAC-1 lymphoma cells from the lungs. The in vivo natural cytotoxicity was increased in running SHRs, and also in SHRs that had their running wheel locked for 24 and 48 h prior to the experiment, and was still present after 96 h. The enhancement of in vivo cytotoxicity after 5 weeks of exercise was abolished after an acute injection of the beta-adrenergic receptor antagonist timolol (0.5 mg kg(-1) i.v.), indicating that catecholamines are involved in this augmentation. Interestingly, 24 h after the last exercise bout, the increased natural cytotoxicity could be blocked by timolol. The opioid receptor antagonist naloxone given subcutaneously for 7 days by osmotic pumps (6 mg kg(-1) h(-1)) could not reverse the increased in vivo cytotoxicity seen in the running SHRs, suggesting that opioid receptor mechanisms are not involved, or at least not the naloxone-sensitive mu-receptor. Natural immunity was not influenced by the histamine H2 receptor antagonist ranitidine, either in controls or in runners, indicating that the natural killer cell-regulatory effect of histamine is not present in SHRs and does not seem to be involved in the exercise-induced changes in natural immune function. We conclude that the augmentation of in vivo natural cytotoxicity after voluntary chronic exercise in rats is long-lasting and that the augmentation is partly mediated by beta-adrenergic receptors.

Simultaneous delivery of cytotoxic and biologic therapeutics using nanophotoactivatable liposomes enhances treatment efficacy in a mouse model of pancreatic cancer.

PubMed

Tangutoori, Shifalika; Spring, Bryan Q; Mai, Zhiming; Palanisami, Akilan; Mensah, Lawrence B; Hasan, Tayyaba

2016-01-01

A lack of intracellular delivery systems has limited the use of biologics such as monoclonal antibodies (mAb) that abrogate molecular signaling pathways activated to promote escape from cancer treatment. We hypothesized that intracellular co-delivery of the photocytotoxic chromophore benzoporphyrin derivative monoacid A (BPD) and the anti-VEGF mAb bevacizumab in a nanophotoactivatable liposome (nanoPAL) might enhance the efficacy of photodynamic therapy (PDT) combined with suppression of VEGF-mediated signaling pathways. As a proof-of-concept we found that nanoPAL-PDT induced enhanced extra- and intracellular bevacizumab delivery and enhanced acute cytotoxicity in vitro. In an in vivo subcutaneous mouse model of pancreatic ductal adenocarcinoma, nanoPAL-PDT achieved significantly enhanced tumor reduction. We attribute this to the optimal incorporation of insoluble BPD into the lipid bilayer, enhancing photocytotoxicity, and the simultaneous spatiotemporal delivery of bevacizumab, ensuring efficient neutralization of the rapid but transient burst of VEGF following PDT. From the Clinical Editor: Most patients with pancreatic ductal adenocarcinoma (PDAC) by the time present the disease it is very advanced, which unavoidably translates to poor survival. For these patients, use of traditional chemotherapy often becomes ineffective due to tumor resistance to drugs. Photodynamic therapy (PDT) can be an effective modality against chemo-resistant cancers. In this article, the authors investigated the co-delivery of a photocytotoxic agent and anti-VEGF mAb using liposomes. This combination was shown to results in enhanced tumor killing. This method should be applicable to other combination of treatments. Copyright © 2015 Elsevier Inc. All rights reserved.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Honma, Yuichi; Harada, Masaru, E-mail: msrharada@med.uoeh-u.ac.jp

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 onmore » 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.« less

Roles of phospholipid methyltransferases in pycnidia development, stress tolerance and secondary metabolism in the taxol-producing fungus Pestalotiopsis microspore.

PubMed

Akhberdi, Oren; Zhang, Qian; Wang, Haichuan; Li, Yingying; Chen, Longfei; Wang, Dan; Yu, Xi; Wei, Dongsheng; Zhu, Xudong

2018-05-01

Phosphatidylcholine (PC) is an important membrane component of the eukaryotic cell. In yeast fungi, two phospholipid methyltransferases catalyze consecutive steps of methylation in the formation of phosphatidylcholine from phosphatidylethanolamine. However, roles of phospholipid methyltransferases in filamentous fungi remains less investigated. We report here the characterization of two genes, choA and choC, that putatively encoded phospholipid methyltransferases in the taxol-producing fungus Pestalotiopsis microspora. Deletion of choC resulted in defects in PC production, vegetative growth and development of asexual structure. The mutant strains exhibited multiple morphological abnormalities, e.g. swollen hyphal tips and enhanced hyphal branching, and even mycelial autolysis. Some novel roles for the genes were also revealed, for instance, the deletion of either choC or choA impaired the development of pycnidia and conidia, the cell wall integrity. The mutant strains displayed a hypersensitivity to stress conditions, e.g. osmotic stress, cold and metal ions. The osmotic hypersensitivity indicates a crosstalk of PC pathways to other signaling pathways, such as the HOG pathway. Still more, choA, but not choC, was required for the production of secondary metabolites, e.g. pestalotiollide B, suggesting distinct roles of the two genes. This work would contribute to better understanding the function of phospholipid methyltransferases in fungi. Copyright © 2018 Elsevier GmbH. All rights reserved.

Cytotoxic effects of residual chemicals from polymeric biomaterials for artificial soft intraocular lenses.

PubMed

Chirila, T V; Walker, L N; Constable, I J; Thompson, D E; Barrett, G D

1991-03-01

Development of improved hydrogels for soft intraocular lenses, based on 2-hydroxyethyl methacrylate monomer, requires the use of various other monomers and polymerization additives which have potential ocular toxicity. Three monomers, 2-hydroxyethyl methacrylate, methyl methacrylate, and 2-ethoxyethyl methacrylate, as well as two common inhibitors, hydroquinone and 4-methoxyphenol, were subjected to in vitro cytotoxicity assays as aqueous solutions at different concentrations. A new polymerization initiator, 2,2'-azo-bis-(2,4-dimethyl valeronitrile), was thermally decomposed in water at different concentrations and the products were also assayed for cytotoxicity. Assays were based on incubation with human choroidal fibroblasts. Cell death was evaluated by trypan blue dye exclusion, DNA synthesis inhibition, and lactate dehydrogenase tests. While methyl methacrylate and 2-ethoxyethyl methacrylate were found nontoxic, the other chemicals displayed high cytotoxicity. However, when extracts of synthesized poly(2-hydroxyethyl methacrylate) specimens, differentially treated after polymerization, were subjected to the same assays it was found that toxicity from residual 2-hydroxyethyl methacrylate monomer was lost during steam sterilization and storage in water because of the removal of the monomer through aqueous washing. The lack of toxicity in these specimens suggests that residual contents of inhibitor and initiator are too low to cause toxic effects on choroidal fibroblasts. It is concluded that hydrogels have low cytotoxic effects in vitro.

Solar light irradiation significantly reduced cytotoxicity and disinfection byproducts in chlorinated reclaimed water.

PubMed

Lv, Xiao-Tong; Zhang, Xue; Du, Ye; Wu, Qian-Yuan; Lu, Yun; Hu, Hong-Ying

2017-11-15

Chlorinated reclaimed water is widely used for landscaping and recreational purposes, resulting in human exposure to toxic disinfection byproducts. Although the quality of chlorinated reclaimed water might be affected by sunlight during storage, the effects of solar light irradiation on the toxicity remain unknown. This study investigated the changes in cytotoxicity and total organic halogen (TOX) of chlorinated reclaimed water exposed to solar light. Irradiation with solar light for 12 h was found to significantly reduce the cytotoxicity of chlorinated reclaimed water by about 75%, with ultraviolet light being responsible for the majority of this reduction. Chlorine residual in reclaimed water tended to increase the cytotoxicity, and the synergy between solar light and free chlorine could not enhance the reduction of cytotoxicity. Adding hydroxyl radical scavengers revealed that the contribution of hydroxyl radical to cytotoxicity reduction was limited. Solar light irradiation concurrently reduced TOX. The low molecular weight (<1 kDa) fraction was the major contributor of cytotoxicity and TOX in chlorinated reclaimed water. Detoxification of the low molecular weight fraction by light irradiation was mainly a result of TOX dehalogenation, while detoxification of the high molecular weight (>1 kDa) fraction was probably caused by photoconversion from high toxic TOX to low toxic TOX. Copyright © 2017 Elsevier Ltd. All rights reserved.

Cyclosporine A and palmitic acid treatment synergistically induce cytotoxicity in HepG2 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Luo, Yi, E-mail: yi.luo@pfizer.com; Rana, Payal; Will, Yvonne

Immunosuppressant cyclosporine A (CsA) treatment can cause severe side effects. Patients taking immunosuppressant after organ transplantation often display hyperlipidemia and obesity. Elevated levels of free fatty acids have been linked to the etiology of metabolic syndromes, nonalcoholic fatty liver and steatohepatitis. The contribution of free fatty acids to CsA-induced toxicity is not known. In this study we explored the effect of palmitic acid on CsA-induced toxicity in HepG2 cells. CsA by itself at therapeutic exposure levels did not induce detectible cytotoxicity in HepG2 cells. Co-treatment of palmitic acid and CsA resulted in a dose dependent increase in cytotoxicity, suggesting thatmore » fatty acid could sensitize cells to CsA-induced cytotoxicity at the therapeutic doses of CsA. A synergized induction of caspase-3/7 activity was also observed, indicating that apoptosis may contribute to the cytotoxicity. We demonstrated that CsA reduced cellular oxygen consumption which was further exacerbated by palmitic acid, implicating that impaired mitochondrial respiration might be an underlying mechanism for the enhanced toxicity. Inhibition of c-Jun N-terminal kinase (JNK) attenuated palmitic acid and CsA induced toxicity, suggesting that JNK activation plays an important role in mediating the enhanced palmitic acid/CsA-induced toxicity. Our data suggest that elevated FFA levels, especially saturated FFA such as palmitic acid, may be predisposing factors for CsA toxicity, and patients with underlying diseases that would elevate free fatty acids may be susceptible to CsA-induced toxicity. Furthermore, hyperlipidemia/obesity resulting from immunosuppressive therapy may aggravate CsA-induced toxicity and worsen the outcome in transplant patients. -- Highlights: ► Palmitic acid and cyclosporine (CsA) synergistically increased cytotoxicity. ► The impairment of mitochondrial functions may contribute to the enhanced toxicity. ► Inhibition of JNK activity

Anti-inflammatory, anti-cholinergic and cytotoxic effects of Sida rhombifolia.

PubMed

Mah, Siau Hui; Teh, Soek Sin; Ee, Gwendoline Cheng Lian

2017-12-01

Sida (Malvaceae) has been used as a traditional remedy for the treatment of diarrhoea, malarial, gastrointestinal dysentery, fevers, asthma and inflammation. This study evaluates the anti-inflammatory, cytotoxic and anti-cholinergic activities of Sida rhombifolia Linn. whole plant for the first time. S. rhombifolia whole plant was extracted by n-hexane, ethyl acetate and methanol using Soxhlet apparatus. The plant extracts were evaluated for their antioxidant (DPPH, FIC and FRAP), anti-inflammatory (NO and protein denaturation inhibitions), cytotoxic (MTT) and anti-cholinesterase (AChE) properties in a range of concentrations to obtain IC 50 values. GC-MS analysis was carried out on the n-hexane extract. The ethyl acetate extract exhibited the most significant antioxidant activities by scavenging DPPH radicals and ferrous ions with EC 50 of 380.5 and 263.4 μg/mL, respectively. In contrast, the n-hexane extract showed the strongest anti-inflammatory activity with IC 50 of 52.16 and 146.03 μg/mL for NO and protein denaturation inhibition assays, respectively. The same extract also revealed the strongest effects in anti-cholinesterase and cytotoxic tests at the concentration of 100 μg/mL, AChE enzyme inhibition was 58.55% and human cancer cells, SNU-1 and Hep G2 inhibition was 68.52% and 47.82%, respectively. The phytochemicals present in the n-hexane extract are palmitic acid, linoleic acid and γ-sitosterol. The present study revealed that the n-hexane extract possessed relatively high pharmacological activities in anti-inflammation, cytotoxicity and anti-cholinesterase assays. Thus, further work on the detail mechanism of the bioactive phytochemicals which contribute to the biological properties are strongly recommended.

Atorvastatin Promotes Cytotoxicity and Reduces Migration and Proliferation of Human A172 Glioma Cells.

PubMed

Oliveira, Karen A; Dal-Cim, Tharine; Lopes, Flávia G; Ludka, Fabiana K; Nedel, Cláudia B; Tasca, Carla I

2018-02-01

Malignant gliomas have resistance mechanisms to chemotherapy that enable tumor invasiveness and aggressiveness. Alternative therapies in cancer treatment, as statins, have been suggested to decrease proliferation, inhibit cell migration, and induce cell death. The aim of this study was to evaluate the effect of atorvastatin (ATOR) on cell viability, migration, proliferation, apoptosis, and autophagy in A172 human glioma cells. Temozolomide (TMZ), a chemotherapic used to glioma treatment, was tested as a comparison to cytotoxic effects on gliomas. Cell viability was also assessed in primary culture of cortical astrocytes. ATOR treatment (0.1 to 20 μM) did not alter astrocytic viability. However, in glioma cells, ATOR showed cytotoxic effect at 10 and 20 μM concentrations. TMZ (500 μM) reduced cell viability similarly to ATOR, and drug association did not show additive effect on cell viability. ATOR, TMZ, and their association decreased cell migration. ATOR also decreased glioma cell proliferation. ATOR increased apoptosis, and TMZ association showed a potentiation effect, enhancing it. ATOR and TMZ treatment increased acidic vesicular organelle (AVO) presence in A172 cells, an indicative of autophagy. ATOR effect of reducing A172 cell viability did not alter glutamate transport and glutamine synthetase activity, but it was partially prevented through antagonism of ionotropic and metabotropic glutamate receptors. Our data shows a cytotoxic effect of ATOR on glioma cells, whereas no toxicity was observed to astrocytes. ATOR showed similar cytotoxic effect as TMZ to glioma cells, and it may be a safer drug, regarding side effect induction, than chemotherapic agents.

Chemically dispersed oil is cytotoxic and genotoxic to sperm whale skin cells.

PubMed

Wise, Catherine F; Wise, James T F; Wise, Sandra S; Wise, John Pierce

2018-06-01

Two major oil crises in United States history, the 1989 Exxon-Valdez oil spill in Alaska and the 2010 Deepwater Horizon Oil Rig explosion in the Gulf of Mexico, drew attention to the need for toxicological experiments on oil and chemically dispersed oil. We are still learning the effects these spills had on wildlife. However, little data is known about the toxicity of these substances in marine mammals. The objective of this study is to determine the toxicity of Alaskan oil, as well as chemically dispersed oil. Oil experiments were performed using the water accommodated fraction of Alaskan oil (WAF) and the chemically enhanced water accommodated fraction of Alaskan oil (CEWAF). The Alaskan WAF is not cytotoxic to sperm whale skin cells though it did induce chromosome damage; S9-mediated metabolism did not affect the cytotoxicity of WAF but did increase the levels of chromosome damage. Alaskan CEWAF is more cytotoxic and genotoxic than the WAF; S9 mediated metabolism increased both cytotoxicity and genotoxicity of CEWAF. Analysis of the PAH content of Alaskan WAF and CEWAF revealed a forty-fold increase in the total levels of PAHs in CEWAF compared to WAF. These findings show that chemically dispersed oil leads to higher levels of PAH exposure which are more toxic and likely to lead to longer and more persistent health effects. Copyright © 2017 Elsevier Inc. All rights reserved.

PEGylation of polypropylenimine dendrimers: effects on cytotoxicity, DNA condensation, gene delivery and expression in cancer cells.

PubMed

Somani, Sukrut; Laskar, Partha; Altwaijry, Najla; Kewcharoenvong, Paphitchaya; Irving, Craig; Robb, Gillian; Pickard, Benjamin S; Dufès, Christine

2018-06-20

Diaminobutyric polypropylenimine (DAB) dendrimers have been shown to be highly efficient non-viral gene delivery systems for cancer therapy. However, their cytotoxicity currently limits their applications. To overcome this issue, PEGylation of DAB dendrimer, using various PEG molecular weights and dendrimer generations, has been attempted to decrease the cytotoxicity and enhance the DNA condensation, size and zeta potential, cellular uptake and transfection efficacy of these dendriplexes. Among all the PEGylated dendrimers synthesized, generation 3- and generation 4-DAB conjugated to low molecular weight PEG (2 kDa) at a dendrimer: DNA ratio of 20:1 and 10:1 resulted in an increase in gene expression on almost all tested cancer cells lines (by up to 3.2-fold compared to unmodified dendrimer in A431 cells). The highest level of β-galactosidase gene expression (10.07 × 10 -3  ± 0.09 × 10 -3  U/mL) was obtained following treatment of B16F10-Luc cells with G4-dendrimer PEGylated with PEG2K at a dendrimer: DNA ratio of 20:1. These delivery systems significantly decreased cytotoxicity on B16F10-Luc cells, by more than 3.4-fold compared to unmodified dendrimer. PEGylated generations 3- and 4-DAB dendrimers are therefore promising gene delivery systems for cancer therapy, combining low cytotoxicity and high transfection efficacy.

A multifunctional lipid nanoparticle for co-delivery of paclitaxel and curcumin for targeted delivery and enhanced cytotoxicity in multidrug resistant breast cancer cells

PubMed Central

Baek, Jong-Suep; Cho, Cheong-Weon

2017-01-01

The objective of the work was to develop a multifunctional nanomedicine based on a folate-conjugated lipid nanoparticles loaded with paclitaxel and curcumin. The novel system combines therapeutic advantageous of efficient targeted delivery via folate and timed-release of curcumin and paclitaxel via 2-hydroxypropyl-ß-cyclodextrin, thereby overcoming multidrug resistance in breast cancer cells (MCF-7/ADR). The faster release of curcumin from the folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles enables sufficient p-glycoprotein inhibition, which allows increased cellular uptake and cytotoxicity of paclitaxel. In western blot assay, curcumin can efficiently inhibit the expression of p-glycoprotein, conformed the enhancement of cytotoxicity by paclitaxel. Furthermore, folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles exhibited increased uptake of paclitaxel and curcumin into MCF-7/ADR cells through the folate receptor-mediated internalization. Taken together, these results indicate that folate-conjugated curcumin and paclitaxel-loaded lipid nanoparticles enables the enhanced, folate-targeted delivery of multiple anticancer drugs by inhibiting the multi-drug resistance efficiently, which may also serve as a useful nano-system for co-delivery of other anticancer drugs. PMID:28423731

Synergistic cytotoxic effects of ions released by zinc-aluminum bronze and the metallic salts on osteoblastic cells.

PubMed

Grillo, Claudia A; Morales, María L; Mirífico, María V; Fernández Lorenzo de Mele, Mónica A

2013-07-01

The use of copper-based alloys for fixed dental crowns and bridges is increasingly widespread in several countries. The aim of this work is to study the dissolution of a zinc-aluminum-bronze and the cytotoxic effects of the ions released on UMR-106 osteoblastic cell line. Two sources of ions were used: (1) ions released by the metal alloy immersed in the cell culture and (2) salts of the metal ions. Conventional electrochemical techniques, atomic absorption spectroscopy [to obtain the average concentration of ions (AC) in solution], and energy dispersive X-ray (EDX) spectroscopy analysis were used to study the corrosion process. Corrosion tests revealed a strong influence of the composition of the electrolyte medium and the immersion time on the electrochemical response. The cytotoxicity was evaluated with (a) individual ions, (b) combinations of two ions, and (c) the mixture of all the ions released by a metal disc of the alloy. Importantly, synergistic cytotoxic effects were found when Al-Zn ion combinations were used at concentration levels lower than the cytotoxic threshold values of the individual ions. Cytotoxic effects in cells in the vicinity of the metal disc were also found. These results were interpreted considering synergistic effects and a diffusion controlled mechanism that yields to concentration levels, in the metal surroundings, several times higher than the measured AC value. Copyright © 2013 Wiley Periodicals, Inc.

Cytotoxic effect of the Her-2/Her-1 inhibitor PKI-166 on renal cancer cells expressing the connexin 32 gene.

PubMed

Fujimoto, Eriko; Yano, Tomohiro; Sato, Hiromi; Hagiwara, Kiyokazu; Yamasaki, Hiroshi; Shirai, Sumiko; Fukumoto, Keiko; Hagiwara, Hiromi; Negishi, Etsuko; Ueno, Koichi

2005-02-01

We have reported that connexin (Cx) 32 acts as a tumor suppressor gene in renal cancer cells partly due to Her-2 inactivation. Here, we determined if a Her-2/Her-1 inhibitor (PKI-166) can enhance the tumor-suppressive effect of Cx32 in Caki-2 cells from human renal cell carcinoma. The expression of Cx32 in Caki-2 cells was required for PKI-166-induced cytotoxic effect at lower doses. The cyctotoxicity was dependent on the occurrence of apoptosis and partly mediated by Cx32-driven gap junction intercellular communications. These results suggest that PKI-166 further supports the tumor-suppressive effect of the Cx32 gene in renal cancer cells through the induction of apoptosis.

Enhancement of antibody-dependent cellular cytotoxicity of cetuximab by a chimeric protein encompassing interleukin-15.

PubMed

Ochoa, Maria Carmen; Minute, Luna; López, Ascensión; Pérez-Ruiz, Elisabeth; Gomar, Celia; Vasquez, Marcos; Inoges, Susana; Etxeberria, Iñaki; Rodriguez, Inmaculada; Garasa, Saray; Mayer, Jan-Peter Andreas; Wirtz, Peter; Melero, Ignacio; Berraondo, Pedro

2018-01-01

Enhancement of antibody-dependent cellular cytotoxicity (ADCC) may potentiate the antitumor efficacy of tumor-targeted monoclonal antibodies. Increasing the numbers and antitumor activity of NK cells is a promising strategy to maximize the ADCC of standard-of-care tumor-targeted antibodies. For this purpose, we have preclinically tested a recombinant chimeric protein encompassing the sushi domain of the IL15Rα, IL-15, and apolipoprotein A-I (Sushi-IL15-Apo) as produced in CHO cells. The size-exclusion purified monomeric fraction of this chimeric protein was stable and retained the IL-15 and the sushi domain bioactivity as measured by CTLL-2 and Mo-7e cell proliferation and STAT5 phosphorylation in freshly isolated human NK and CD8 + T cells. On cell cultures, Sushi-IL15-Apo increases NK cell proliferation and survival as well as spontaneous and antibody-mediated cytotoxicity. Scavenger receptor class B type I (SR-B1) is the receptor for ApoA-I and is expressed on the surface of tumor cells. SR-B1 can adsorb the chimeric protein on tumor cells and can transpresent IL-15 to NK and CD8 + T cells. A transient NK-humanized murine model was developed to test the increase of ADCC attained by the chimeric protein in vivo . The EGFR + human colon cancer cell line HT-29 was intraperitoneally inoculated in immune-deficient Rag2 -/- γc -/- mice that were reconstituted with freshly isolated PBMCs and treated with the anti-EGFR mAb cetuximab. The combination of the Sushi-IL15-Apo protein and cetuximab reduced the number of remaining tumor cells in the peritoneal cavity and delayed tumor engraftment in the peritoneum. Furthermore, Sushi-IL15-Apo increased the anti-tumor effect of a murine anti-EGFR mAb in Rag1 -/- mice bearing subcutaneous MC38 colon cancer transfected to express EGFR. Thus, Sushi-IL15-Apo is a potent tool to increase the number and the activation of NK cells to promote the ADCC activity of antibodies targeting tumor antigens.

Effects of folic acid deficiency and MTHFRC677T polymorphisms on cytotoxicity in human peripheral blood lymphocytes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu Xiayu; Liang Ziqing; Zou Tianning

2009-02-13

Apoptosis (APO) and necrosis (NEC) are two different types of cell death occurring in response to cellular stress factors. Cells with DNA damage may undergo APO or NEC. Folate is an essential micronutrient associated with DNA synthesis, repair and methylation. Methylenetetrahydrofolate reductase (MTHFR) regulates intracellular folate metabolism. Folate deficiency and MTHFR C677T polymorphisms have been shown to be related to DNA damage. To verify the cytotoxic effects of folate deficiency on cells with different MTHFR C677T genotypes, 15 human peripheral lymphocyte cases with different MTHFR C677T genotypes were cultured in folic acid (FA)-deficient and -sufficient media for 9 days. Cytotoxicitymore » was quantified using the frequencies of APO and NEC as endpoints, the nuclear division index (NDI), and the number of viable cells (NVC). These results showed that FA is an important factor in reducing cytotoxicity and increasing cell proliferation. Lymphocytes with the TT genotype proliferated easily under stress and exhibited different responses to FA deficiency than lymphocytes with the CC and CT genotypes. A TT individual may accumulate more cytotoxicity under cytotoxic stress, suggesting that the effects of FA deficiency on cytotoxicity are greater than the effects in individuals with the other MTHFR C677T variants.« less

The ginsenoside PPD exerts anti-endometriosis effects by suppressing estrogen receptor-mediated inhibition of endometrial stromal cell autophagy and NK cell cytotoxicity.

PubMed

Zhang, Bing; Zhou, Wen-Jie; Gu, Chun-Jie; Wu, Ke; Yang, Hui-Li; Mei, Jie; Yu, Jia-Jun; Hou, Xiao-Fan; Sun, Jian-Song; Xu, Feng-Yuan; Li, Da-Jin; Jin, Li-Ping; Li, Ming-Qing

2018-05-14

Endometriosis (EMS) is an estrogen-dependent gynecological disease with a low autophagy level of ectopic endometrial stromal cells (eESCs). Impaired NK cell cytotoxic activity is involved in the clearance obstruction of the ectopic endometrial tissue in the abdominopelvic cavity. Protopanaxadiol (PPD) and protopanaxatriol (PPT) are two metabolites of ginsenosides, which have profound biological functions, such as anti-cancer activities. However, the role and mechanism of ginsenosides and metabolites in endometriosis are completely unknown. Here, we found that the compounds PPD, PPT, ginsenoside-Rg3 (G-Rg3), ginsenoside-Rh2 (G-Rh2), and esculentoside A (EsA) led to significant decreases in the viability of eESCs, particularly PPD (IC50 = 30.64 µM). In vitro and in vivo experiments showed that PPD promoted the expression of progesterone receptor (PR) and downregulated the expression of estrogen receptor α (ERα) in eESCs. Treatment with PPD obviously induced the autophagy of eESCs and reversed the inhibitory effect of estrogen on eESC autophagy. In addition, eESCs pretreated with PPD enhanced the cytotoxic activity of NK cells in response to eESCs. PPD decreased the numbers and suppressed the growth of ectopic lesions in a mouse EMS model. These results suggest that PPD plays a role in anti-EMS activation, possibly by restricting estrogen-mediated autophagy regulation and enhancing the cytotoxicity of NK cells. This result provides a scientific basis for potential therapeutic strategies to treat EMS by PPD or further structural modification.

Cytotoxicity and therapeutic effect of irinotecan combined with selenium nanoparticles.

PubMed

Gao, Fuping; Yuan, Qing; Gao, Liang; Cai, Pengju; Zhu, Huarui; Liu, Ru; Wang, Yaling; Wei, Yueteng; Huang, Guodong; Liang, Jian; Gao, Xueyun

2014-10-01

Although chemotherapeutic drugs are widely applied for clinic tumor treatment, severe toxicity restricts their therapeutic efficacy. In this study, we reported a new form of selenium, selenium nanoparticles (Nano Se) which have significant lower toxicity and acceptable bioavailability. We investigated Nano Se as chemotherapy preventive agent to protect against toxicities of anticancer drug irinotecan and synergistically enhance the anti-tumor treatment effect in vitro and in vivo. The underlying mechanisms were also investigated. The combination of Nano Se and irinotecan showed increased cytotoxic effect with HCT-8 tumor cells likely by p53 mediated apoptosis. Nano Se inhibited growth of HCT-8 tumor cells partially through caspases mediated apoptosis. In vivo experiment showed Nano Se at a dose of 4 mg/kg/day significantly alleviated adverse effects induced by irinotecan (60 mg/kg) treatment. Nano Se alone treatment did not induce any toxic manifestations. The combination of Nano Se and irinotecan dramatically inhibited tumor growth and significantly induced apoptosis of tumor cells in HCT-8 cells xenografted tumor. Tumor inhibition rate was about 17.2%, 48.6% and 62.1% for Nano Se, irinotecan and the combination of Nano Se and irinotecan, respectively. The beneficial effects of Nano Se for tumor therapy were mainly ascribed to selectively regulating Nrf2-ARE (antioxidant responsive elements) pathway in tumor tissues and normal tissues. Our results suggest Nano Se is a promising selenium species with potential application in cancer treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Indicine N-oxide binds to tubulin at a distinct site and inhibits the assembly of microtubules: a mechanism for its cytotoxic activity.

PubMed

Appadurai, Prakash; Rathinasamy, Krishnan

2014-02-10

Indicine N-oxide, a pyrrolizidine alkaloid present in the plant Heliotropium indicum had shown promising cytotoxic activity in various tumor models. The compound exhibited severe toxicity to hepatocytes and bone marrow cells. The present work was aimed to evaluate the molecular mechanism of the toxicity of indicine N-oxide. We found that indicine N-oxide inhibited the proliferation of various cancer cell lines in a concentration dependent manner with IC50 ranging from 46 to 100 μM. At the half maximal inhibitory concentration it blocked the cell cycle progression at mitosis without significantly altering the organization of the spindle and interphase microtubules. The toxicities of the compound at higher concentrations are attributed to its severe depolymerizing effect on both the interphase and spindle microtubules. Binding studies using purified goat brain tubulin indicated that indicine N-oxide binds to tubulin at a distinct site not shared by colchicine or taxol. It decreased the polymer mass of both purified tubulin and MAP-rich tubulin. It was found to induce cleavage of DNA using pUC18 plasmid. The interactions of indicine N-oxide on DNA were also confirmed by computational analysis; which predicted its binding site at the minor groove of DNA. These studies bring to light that the toxicities of indicine N-oxide were due to its DNA damaging effects and depolymerization of microtubules. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

The Key Role of Mitochondrial Apoptotic Pathway in the Cytotoxic Effect of Mushroom Extracts on Cancer Cells.

PubMed

Han, Mei; Ling, Ming-Tat; Chen, Jiezhong

2015-01-01

Mushroom extracts have been extensively studied for their medicinal effects. They can stimulate immune responses and thus have been explored in cancer treatment. Recently, it has also been shown that some mushroom extracts can produce direct cytotoxic effect on cancer cells. In this review, we summarize the cytotoxic effect of mushroom extracts in cancer treatment revealed by both in vitro and in vivo studies. We also summarize the current understanding of the mechanisms associated with such an effect with an emphasis on the mitochondrial apoptotic pathway. The recent finding that mushroom extracts have direct cytotoxic effects supplements their known immune stimulating effects. Thus, novel anticancer agents based on new findings from mushroom extracts may soon be added to the present pool of anticancer drugs. Specifically, we propose that nanodelivery of the bioactive compounds of mushroom extracts to mitochondria will further increase their potential treatment efficacy.

Cytotoxic Effects of Re-Activated Lunar Dust Stimulant on Human Lung Cells

NASA Technical Reports Server (NTRS)

Upadhyaya, Krishna

2009-01-01

Lunar dust has been of significant concern due to various problems observed on the Apollo missions. Reports from astronauts have shown that the dust may have caused eye and nasal irritation as well as possible hay fever like symptoms. As NASA hopes to go to the Moon within the next few years, we hope to understand the possible toxic effects the dust might have. In these studies, we are looking at the effect of "re-activated" lunar dust stimulant on human bronchial cells. A simple grinding analog as a method of simulating micrometeorite crushing on the moon is used to "activate" the dust stimulant, i.e. capable of producing hydroxyl radicals. These radicals could then interact with human cells and may lead to a loss in membrane integrity and cell death. (Castranova, 1994) Cells are exposed to the dust for 6 and 24 hour intervals to assess cytotoxicity. Cytotoxicity is measured by looking at the production of inflammatory cytokines. Cells are exposed to ground and unground stimulant and compared to cytokine production from cells exposed to quartz which have a known toxicity. Here we look at the cytotoxicity of the lunar dust stimulant relative to quartz by measuring the production of inflammatory cytokines.

SMIFH2-mediated mDia formin functional inhibition potentiates chemotherapeutic targeting of human ovarian cancer spheroids.

PubMed

Ziske, Megan A; Pettee, Krista M; Khaing, MaNada; Rubinic, Kaitlin; Eisenmann, Kathryn M

2016-03-25

Due to a lack of effective screening or prevention protocol for epithelial ovarian cancer (EOC), there is a critical unmet need to develop therapeutic interventions for EOC treatment. EOC metastasis is unique. Initial dissemination is not primarily hematogenous, yet is facilitated through shedding of primary tumor cells into the peritoneal fluid and accumulating ascites. Increasingly, isolated patient spheroids point to a clinical role for spheroids in EOC metastasis. EOC spheroids are highly invasive structures that disseminate upon peritoneal mesothelium, and visceral tissues including liver and omentum. Selection for this subset of chemoresistant EOC cells could influence disease progression and/or recurrence. Thus, targeting spheroid integrity/structure may improve the chemotherapeutic responsiveness of EOC. We discovered a critical role for mammalian Diaphanous (mDia)-related formin-2 in maintaining EOC spheroid structure. Both mDia2 and the related mDia1 regulate F-actin networks critical to maintain cell-cell contacts and the integrity of multi-cellular epithelial sheets. We investigated if mDia2 functional inhibition via a small molecule inhibitor SMIFH2 combined with chemotherapeutics, such as taxol and cisplatin, inhibits the viability of EOC monolayers and clinically relevant spheroids. SMIFH2-mediated mDia formin inhibition significantly reduced both ES2 and Skov3 EOC monolayer viability while spheroid viability was minimally impacted only at the highest concentrations. Combining either cisplatin or taxol with SMIFH2 did not significantly enhance the effects of either drug alone in ES2 monolayers, while Skov3 monolayers treated with taxol or cisplatin and SMIFH2 showed significant additive inhibition of viability. ES2 spheroids were highly responsive with clear additive anti-viability effects with dual taxol or cisplatin when combined with SMIFH2 treatments. While combined taxol with SMIFH2 in spheroids showed an additive effect relative to single

In vitro and in vivo antithrombotic and cytotoxicity effects of ferulic acid.

PubMed

Choi, Jun-Hui; Park, Jong-Kook; Kim, Ki-Man; Lee, Hyo-Jeong; Kim, Seung

2018-01-01

We discovered recently in vitro and in vivo antithrombotic and cytotoxicity effects of ferulic acid. The cytotoxicity assays showed that ferulic acid (∼300 μg/mL) did not cause any significant toxicity on three cell lines, platelets, leukocytes, and erythrocytes. In vitro assays showed inhibitory effects of ferulic acid on thrombin (THR)- or collagen/epinephrine-stimulated platelet activation by inhibiting platelet aggregation, and decreasing clot retraction activity. The in vitro effect of ferulic acid on THR-stimulated platelet activation was proved by the decrease in the secretion of serotonin from the platelets. The anticoagulant effects of ferulic acid were confirmed by the prolongation of the intrinsic or/and extrinsic pathways and the delay of recalcification time in plasma coagulation. Ferulic acid had antithrombotic effect in acute thromboembolism model in vivo, and decreased the expression of α IIb β 3 /FIB and phosphorylation of AKT in THR-stimulated platelet activation in vivo, and their antithrombotic efficacies hold promise for therapeutic targeting in our ongoing studies. © 2017 Wiley Periodicals, Inc.

Cytotoxicity of isolated compounds from the extracts of Struchium sparganophora (Linn) Ktze asteraceae.

PubMed

Kasim, Lateef Saka; Ferro, Valerie; Odukoya, Oluwakemi A; Ukpo, Grace Eigbibhalu; Seidel, Veronique; Gray, Alexander I; Waigh, Roger

2011-10-01

Chemical investigation of the leaves of Struchium sparganophora by the application of VLC, CL and PTLC resulted in isolation of three compounds. The cytotoxicity activity of these compounds on malignant human cultured cells was examined. Vernodalin showed a significant cytotoxic activity on the melanoma and ovarian cancer cell lines (P<0.05) while the conjugated 3 methyl, 2, 6 hexacosedienol and luteolin caused cell death after 48h reculture without them. These compounds portend an effective remedy if subjected to structural modification to enhance its' efficacy and the dietary importance of this plant as a culinary herb in west Africa countries is evidence by the presence of these antitumour compounds in this plant.

Effect of LTB4 on the inhibition of natural cytotoxic activity by PGE2.

PubMed

Vaillier, D; Daculsi, R; Gualde, N; Bezian, J H

1992-01-01

NK activity is regulated by arachidonic acid metabolites. More precisely PGE2 and LTB4 decreases and increases respectively non-MHC-restricted cytotoxicity in humans. We have observed similar data in mice since NK activity was inhibited by PGE2 (10(-6) to 10(-8) M) and enhanced by LTB4 (10(-8) to 10(-12) M). On the other hand when PGE2 and LTB4 were combined during the same assay the lysis percentage was smaller than the one which was induced by PGE2 alone. Because PGE2 increases intracellular cyclic AMP and that LTB4 augments cyclic GMP we used a cAMP inducer (forskolin) and a cGMP analogue (8 Br-cGMP) instead of eicosanoids and we observed similar data (i.e., a decrease of natural killing) as when PGE2 was combined with LTB4. When splenocytes are cultured for 1-4 days alone, cytotoxic activity decreases unless they are cultured in the presence of indomethacin. Cytotoxic activity of spleen cells cultured in the presence of PGE2 or LTB4 is respectively decreased or increased. However, splenocytes that were cultured alone for at least 24 hr were no longer sensitive to inhibition by PGE2 but were still PGE2-sensitive when cultured in the presence of LTB4.

Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Guo, Li-Wu; Wu, Qiangen; Green, Bridgett

2012-07-15

Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCSmore » (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.« less

Evaluation of cytotoxicity of different tobacco product preparations.

PubMed

Arimilli, Subhashini; Damratoski, Brad E; Bombick, Betsy; Borgerding, Michael F; Prasad, G L

2012-12-01

Acute exposure to cigarette smoke or its components triggers diverse cellular effects, including cytotoxicity. However, available data regarding the potential cytotoxic effects of smokeless tobacco (ST) extracts lack consensus. Here, we investigated the relative biological effects of 2S3 reference ST, and whether ST elicits differential cellular/molecular responses compared to combustible tobacco product preparations (TPPs) prepared from 3R4F cigarettes. Total particulate matter (TPM) and whole smoke conditioned medium (WS-CM) were employed as combustible TPPs, while the ST extract was used as non-combustible TPP. HL60, THP1 cells and human PBMCs were used to examine the effects of TPPs in short-term cell culture. Corresponding EC(50) values, normalized for nicotine content of the TPPs, suggest that combustible TPPs induced higher cytotoxicity as follows: WS-CM TPM ≥ ≫ST extract>nicotine. While all three TPPs induced detectable levels of DNA damage and IL8 secretion, the combustible TPPs were significantly more potent than the ST preparation. The major PBMC subsets showed differential cytotoxicity to combustible TPPs as follows: CD4>CD8>monocytes>NK cells. These findings suggest that, relative cytotoxic and other cell biological effects of TPPs are dose-dependent, and that ST extract is the least cytotoxic TPP tested in this study. Copyright © 2012 Elsevier Inc. All rights reserved.

Antioxidative, antimicrobial and cytotoxic effects of the phenolics of Leea indica leaf extract

PubMed Central

Rahman, Md. Atiar; Imran, Talha bin; Islam, Shahidul

2012-01-01

This study investigated the phytochemical, antioxidative, antimicrobial and cytotoxic effects of Leea indica leaf ethanol extract. Phytochemical values namely total phenolic and flavonoid contents, total antioxidant capacity, DPPH radical scavenging effect, FeCl3 reducing power, DMSO superoxide scavenging effect and Iron chelating effects were studied by established methods. Antibacterial, antifungal and cytotoxic effects were screened by disk diffusion technique, food poison technique and brine shrimp bioassay, respectively. Results showed the total phenolic content 24.00 ± 0.81 g GAE/100 g, total flavonoid content 194.68 ± 2.43 g quercetin/100 g and total antioxidant capacity 106.61 ± 1.84 g AA/100 g dry extract. Significant (P < 0.05) IC50 values compared to respective standards were recorded in DPPH radical scavenging (139.83 ± 1.40 μg/ml), FeCl3 reduction (16.48 ± 0.64 μg/ml), DMSO superoxide scavenging (676.08 ± 5.80 μg/ml) and Iron chelating (519.33 ± 16.96 μg/ml) methods. In antibacterial screening, the extract showed significant (P < 0.05) zone of inhibitions compared to positive controls Ampicillin and Tetracycline against Gram positive Bacillus subtilis, Bacillus cereus, Bacillus megaterium, and Staphylococcus aureus and Gram negative Salmonella typhi, Salmonella paratyphi, Pseudomonas aeroginosa, Shigella dysenteriae, Vibrio cholerae, and Escherichia coli. Significant minimum inhibitory concentrations compared to tetracycline were obtained against the above organisms. In antifungal assay, the extract inhibited the growth of Aspergillus flavus, Candida albicans and Fusarium equisetii by 38.09 ± 0.59, 22.58 ± 2.22, and 22.58 ± 2.22%, respectively. The extract showed a significant LC50 value compared to vincristine sulfate in cytotoxic assay. The results evidenced the potential antioxidative, antimicrobial and cytotoxic capacities of Leea inidica leaf extract to be processed for pharmaceutical use. PMID

Oxygen and indocyanine green loaded phase-transition nanoparticle-mediated photo-sonodynamic cytotoxic effects on rheumatoid arthritis fibroblast-like synoviocytes.

PubMed

Tang, Qin; Cui, Jianyu; Tian, Zhonghua; Sun, Jiangchuan; Wang, Zhigang; Chang, Shufang; Zhu, Shenyin

2017-01-01

Photodynamic therapy and sonodynamic therapy are developing, minimally invasive, and site-specific modalities for cancer therapy. A combined strategy PSDT (photodynamic therapy followed by sonodynamic therapy) has been proposed in this study. Here, we aimed to develop novel biodegradable poly(DL-lactide- co -glycolic acid) phase-transition nanoparticles simultaneously loaded with oxygen and indocyanine green (OI-NPs) and to investigate the cytotoxic effects and the potential mechanisms of OI-NP-mediated PSDT on MH7A synoviocytes. The OI-NPs were prepared using a modified double emulsion method and the physicochemical properties were determined. The cellular uptake of OI-NPs was detected by confocal microscopy and flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay, flow cytometry, and Hoechst 33342/propidium iodide double staining were used to determine the cytotoxic effect of OI-NP-mediated PSDT on MH7A cells. Fluorescence microscope and fluorescence microplate reader were used to detect reactive oxygen species (ROS) generation. The OI-NPs were a stable and efficient carrier to deliver oxygen and indocyanine green, and enhanced cellular uptake was observed in MH7A cells with the nanoparticles. OI-NP-mediated PSDT caused more serious cell damage and more evident cell apoptosis, compared with other groups. Furthermore, increased generation of intracellular ROS was detected in MH7A cells treated with PSDT. Interestingly, the OI-NP-mediated PSDT-induced cell viability loss was effectively rescued by pretreatment with the ROS scavenger N -acetylcysteine. Multifunctional OI-NPs were successfully developed and characterized for the combined delivery of oxygen and indocyanine green, and OI-NP-mediated PSDT would be a potential cytotoxic treatment for MH7A cells. This study may provide a novel strategy for the treatment of RA and develop a model of theranostic application through phase-transition nanoparticle-mediated PSDT in the future.

Oxygen and indocyanine green loaded phase-transition nanoparticle-mediated photo-sonodynamic cytotoxic effects on rheumatoid arthritis fibroblast-like synoviocytes

PubMed Central

Tang, Qin; Cui, Jianyu; Tian, Zhonghua; Sun, Jiangchuan; Wang, Zhigang; Chang, Shufang; Zhu, Shenyin

2017-01-01

Background Photodynamic therapy and sonodynamic therapy are developing, minimally invasive, and site-specific modalities for cancer therapy. A combined strategy PSDT (photodynamic therapy followed by sonodynamic therapy) has been proposed in this study. Here, we aimed to develop novel biodegradable poly(DL-lactide-co-glycolic acid) phase-transition nanoparticles simultaneously loaded with oxygen and indocyanine green (OI-NPs) and to investigate the cytotoxic effects and the potential mechanisms of OI-NP–mediated PSDT on MH7A synoviocytes. Methods The OI-NPs were prepared using a modified double emulsion method and the physicochemical properties were determined. The cellular uptake of OI-NPs was detected by confocal microscopy and flow cytometry. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay, flow cytometry, and Hoechst 33342/propidium iodide double staining were used to determine the cytotoxic effect of OI-NP–mediated PSDT on MH7A cells. Fluorescence microscope and fluorescence microplate reader were used to detect reactive oxygen species (ROS) generation. Results The OI-NPs were a stable and efficient carrier to deliver oxygen and indocyanine green, and enhanced cellular uptake was observed in MH7A cells with the nanoparticles. OI-NP–mediated PSDT caused more serious cell damage and more evident cell apoptosis, compared with other groups. Furthermore, increased generation of intracellular ROS was detected in MH7A cells treated with PSDT. Interestingly, the OI-NP–mediated PSDT-induced cell viability loss was effectively rescued by pretreatment with the ROS scavenger N-acetylcysteine. Conclusion Multifunctional OI-NPs were successfully developed and characterized for the combined delivery of oxygen and indocyanine green, and OI-NP–mediated PSDT would be a potential cytotoxic treatment for MH7A cells. This study may provide a novel strategy for the treatment of RA and develop a model of theranostic application through phase

Sulforaphane increases drug-mediated cytotoxicity toward cancer stem-like cells of pancreas and prostate.

PubMed

Kallifatidis, Georgios; Labsch, Sabrina; Rausch, Vanessa; Mattern, Juergen; Gladkich, Jury; Moldenhauer, Gerhard; Büchler, Markus W; Salnikov, Alexei V; Herr, Ingrid

2011-01-01

Despite intense efforts to develop treatments against pancreatic cancer, agents that cure this highly resistant and metastasizing disease are not available. Considerable attention has focused on broccoli compound sulforaphane (SF), which is suggested as combination therapy for targeting of pancreatic cancer stem cells (CSCs). However, there are concerns that antioxidative properties of SF may interfere with cytotoxic drugs-as suggested, e.g., for vitamins. Therefore we investigated a combination therapy using established pancreatic CSCs. Although cisplatin (CIS), gemcitabine (GEM), doxorubicin, 5-flurouracil, or SF effectively induced apoptosis and prevented viability, combination of a drug with SF increased toxicity. Similarly, SF potentiated the drug effect in established prostate CSCs revealing that SF enhances drug cytotoxicity also in other tumor entities. Most importantly, combined treatment intensified inhibition of clonogenicity and spheroid formation and aldehyde dehydrogenase 1 (ALDH1) activity along with Notch-1 and c-Rel expression indicating that CSC characteristics are targeted. In vivo, combination treatment was most effective and totally abolished growth of CSC xenografts and tumor-initiating potential. No pronounced side effects were observed in normal cells or mice. Our data suggest that SF increases the effectiveness of various cytotoxic drugs against CSCs without inducing additional toxicity in mice.

Sulforaphane Increases Drug-mediated Cytotoxicity Toward Cancer Stem-like Cells of Pancreas and Prostate

PubMed Central

Kallifatidis, Georgios; Labsch, Sabrina; Rausch, Vanessa; Mattern, Juergen; Gladkich, Jury; Moldenhauer, Gerhard; Büchler, Markus W.; Salnikov, Alexei V.; Herr, Ingrid

2011-01-01

Despite intense efforts to develop treatments against pancreatic cancer, agents that cure this highly resistant and metastasizing disease are not available. Considerable attention has focused on broccoli compound sulforaphane (SF), which is suggested as combination therapy for targeting of pancreatic cancer stem cells (CSCs). However, there are concerns that antioxidative properties of SF may interfere with cytotoxic drugs—as suggested, e.g., for vitamins. Therefore we investigated a combination therapy using established pancreatic CSCs. Although cisplatin (CIS), gemcitabine (GEM), doxorubicin, 5-flurouracil, or SF effectively induced apoptosis and prevented viability, combination of a drug with SF increased toxicity. Similarly, SF potentiated the drug effect in established prostate CSCs revealing that SF enhances drug cytotoxicity also in other tumor entities. Most importantly, combined treatment intensified inhibition of clonogenicity and spheroid formation and aldehyde dehydrogenase 1 (ALDH1) activity along with Notch-1 and c-Rel expression indicating that CSC characteristics are targeted. In vivo, combination treatment was most effective and totally abolished growth of CSC xenografts and tumor-initiating potential. No pronounced side effects were observed in normal cells or mice. Our data suggest that SF increases the effectiveness of various cytotoxic drugs against CSCs without inducing additional toxicity in mice. PMID:20940707

Controlled cytotoxicity of plasma treated water formulated by open-air hybrid mode discharge

NASA Astrophysics Data System (ADS)

Lu, P.; Boehm, D.; Cullen, P.; Bourke, P.

2017-06-01

Plasma treated liquids (PTLs) provide a means to convey a broad range of effects of relevance for food, environmental, or clinical decontamination, plant growth promotion, and therapeutic applications. Devising the reactive species ingredients and controlling the biological response of PTLs are of great interest. We demonstrate an approach by using an open-air hybrid mode discharge (HMD) to control the principal reactive species composition within plasma treated water (PTW), which is then demonstrated to regulate the cytotoxicity of PTW. The cytotoxicity of HMD produced PTW demonstrates a non-monotonic change over the discharge time. Although hydrogen peroxide and nitrite are not the sole effectors for cell death caused by PTW, using them as principal reactive species indicators, cytotoxicity can be removed and/or enhanced by formulating their concentrations and composition through adjusting the discharge mode and time on-line during PTW generation without the addition of additional working gas or chemical scavengers. This work demonstrates that a hybrid mode discharge can be employed to generate a PTW formulation to control a biological response such as cytotoxicity. This provides insights into how plasma treated liquids may be harnessed for biological applications in a specific and controllable manner.

Enhanced preferential cytotoxicity through surface modification: synthesis, characterization and comparative in vitro evaluation of TritonX-100 modified and unmodified zinc oxide nanoparticles in human breast cancer cell (MDA-MB-231).

PubMed

Kc, Biplab; Paudel, Siddhi Nath; Rayamajhi, Sagar; Karna, Deepak; Adhikari, Sandeep; Shrestha, Bhupal G; Bisht, Gunjan

2016-01-01

biocompatible surface coating. Both samples show significantly less toxicity towards NIH 3T3 in concentration independent manner. But use of Triton-X, a biocompatible polymer, enhances this preferentiality effect. Since therapeutic significance should be analyzed through its comparative effect on both normal and cancer cells, possible application of biocompatible polymer modified nanoparticles as therapeutic agent holds better promise.Graphical abstractSurface coating, characterization and comparative in vitro cytotoxicity study on MDA-MB 231 and NIH 3T3 of ZnO NPs showing enhanced preferentiality by biocompatible surface modification.

In vitro immunomodulatory activity, cytotoxicity and chemistry of some central European polypores.

PubMed

Doskocil, Ivo; Havlik, Jaroslav; Verlotta, Roberta; Tauchen, Jan; Vesela, Lucia; Macakova, Katerina; Opletal, Lubomir; Kokoska, Ladislav; Rada, Vojtech

2016-11-01

Context Some mushrooms of the order Polyporales are known for their immunomodulatory actions. Objective The objective of this study is to evaluate the in vitro phagocytic and cytotoxic effects of extracts from polyporales native to Central Europe. Materials and methods The effects of ethanol extracts from 27 polypore species on opsonized zymosan-induced phagocytosis of isolated human neutrophils were tested by a chemiluminescence method. Colon epithelial cell lines, Caco-2 and HT-29, were used for cytotoxicity assays, and extracts were chemically characterized in terms of total phenolic and β-glucan content. Results We observed phagocytosis or respiratory burst enhancing activity in 17 extracts, of which five species, namely Aurantiporus fissilis (Berk. & M.A. Curtis) H. Jahn ex Ryvarden, Trametes gibbosa (Pers.) Fr., Piptoporus betulinus (Bull.) P. Karst, Neolentinus lepideus (Fr.) Redhead & Ginns, Polyporus squamosus (Huds.) Fr., significantly increased phagocytosis in granulocytes by 205, 181, 158, 155 and 141%, respectively. The β-glucan content of the three most potent extracts was 58, 42 and 74 mg/g, respectively, and the polyphenol content was 155.6, 133.5 and 155.2 μmol of gallic acid equivalent/g, respectively. Some extracts showed cytotoxic activity, with higher cytotoxicity in Caco-2 than in HT-29 cells. Pycnoporus cinnabarinus (Jacq.) P. Karst. extract was cytotoxic to both cell lines, with IC 50 values of 81 and 31 μg/mL, respectively. Discussion and conclusion The most promising extracts were from N. lepideus and Polyporus squamosus, which are edible species and may be considered safe. Our findings support their use as culinary preparations or food supplements for various immunological gut disorders.

Physico-chemical properties and cytotoxic effects of sugar-based surfactants: Impact of structural variations.

PubMed

Lu, Biao; Vayssade, Muriel; Miao, Yong; Chagnault, Vincent; Grand, Eric; Wadouachi, Anne; Postel, Denis; Drelich, Audrey; Egles, Christophe; Pezron, Isabelle

2016-09-01

Surfactants derived from the biorefinery process can present interesting surface-active properties, low cytotoxicity, high biocompatibility and biodegradability. They are therefore considered as potential sustainable substitutes to currently used petroleum-based surfactants. To better understand and anticipate their performances, structure-property relationships need to be carefully investigated. For this reason, we applied a multidisciplinary approach to systematically explore the effect of subtle structural variations on both physico-chemical properties and biological effects. Four sugar-based surfactants, each with an eight carbon alkyl chain bound to a glucose or maltose head group by an amide linkage, were synthesized and evaluated together along with two commercially available standard surfactants. Physico-chemical properties including solubility, Krafft point, surface-tension lowering and critical micellar concentration (CMC) in water and biological medium were explored. Cytotoxicity evaluation by measuring proliferation index and metabolic activity against dermal fibroblasts showed that all surfactants studied may induce cell death at low concentrations (below their CMC). Results revealed significant differences in both physico-chemical properties and cytotoxic effects depending on molecule structural features, such as the position of the linkage on the sugar head-group, or the orientation of the amide linkage. Furthermore, the cytotoxic response increased with the reduction of surfactant CMC. This study underscores the relevance of a methodical and multidisciplinary approach that enables the consideration of surfactant solution properties when applied to biological materials. Overall, our results will contribute to a better understanding of the concomitant impact of surfactant structure at physico-chemical and biological levels. Copyright © 2016 Elsevier B.V. All rights reserved.

Mitigation of Quantum Dot Cytotoxicity by Microencapsulation

PubMed Central

Romoser, Amelia; Ritter, Dustin; Majitha, Ravish; Meissner, Kenith E.; McShane, Michael; Sayes, Christie M.

2011-01-01

When CdSe/ZnS-polyethyleneimine (PEI) quantum dots (QDs) are microencapsulated in polymeric microcapsules, human fibroblasts are protected from acute cytotoxic effects. Differences in cellular morphology, uptake, and viability were assessed after treatment with either microencapsulated or unencapsulated dots. Specifically, QDs contained in microcapsules terminated with polyethylene glycol (PEG) mitigate contact with and uptake by cells, thus providing a tool to retain particle luminescence for applications such as extracellular sensing and imaging. The microcapsule serves as the “first line of defense” for containing the QDs. This enables the individual QD coating to be designed primarily to enhance the function of the biosensor. PMID:21814567

Lipoplexes prepared from cationic liposomes and mammalian DNA induce CpG-independent, direct cytotoxic effects in cell cultures and in mice.

PubMed

Khazanov, Elena; Simberg, Dmitri; Barenholz, Yechezkel

2006-08-01

Recent studies demonstrated the cytotoxic activity of bacterial DNA (pDNA) complexed with cationic lipids. This cytotoxicity is related to the ability of pDNA to induce potently the immune system, which is associated with release of inflammatory cytokines. Both activities seem to be related to the nonmethylated CpG sequences present in the pDNA. Here we study the cytotoxic activity of nonbacterial DNA complexed with cationic lipids against various tumor cell lines. Various nucleic acids complexed with cationic liposomes were prepared and their cytotoxic activity was studied in cell cultures and in tumor-bearing mice. Cell uptake of lipoplexes was evaluated, and mechanism of DNA cytotoxic activity was studied. We found that nonbacterial (vertebrate) genomic DNA when complexed with cationic lipids is highly cytotoxic against C-26 and M-109 tumor cells. Cationic lipids alone were not toxic to these cells. The cytotoxic activity does not result from nonspecific acidification of the intracellular milieu, as substitution of DNA by poly-L-glutamate did not result in cytotoxicity, although the level of uptake of anionic charges per cell was similar to that of the nucleic acids, suggesting that this cytotoxic effect is specific to nucleic acids. By studying the nucleic acid fate using confocal microscopy, we found that cytotoxicity correlated with the release of DNA into the cytoplasm following uptake of lipoplexes. Injection of calf thymus DNA-based lipoplexes to mice with peritoneal C-26 metastases resulted in doubling of median survival time and long-term survival in 20% of the tumor-bearing mice. Judging by low levels of IFN-gamma, TNF-alpha and IL-6 in the treated mice, this effect cannot be ascribed to Th-1 inflammation, but rather to a direct cytotoxic effect on the tumor cells. The above data provide a new insight into the mechanisms of lipoplex-mediated antitumor effects in vitro and in vivo and new perspectives in cancer therapy. 2006 John Wiley & Sons, Ltd.

Cytotoxic effects of dimethyl sulphoxide (DMSO) on cochlear organotypic cultures

PubMed Central

Qi, Weidong; Ding, Dalian; Salvi*, Richard J.

2008-01-01

The amphipathic molecule dimethyl sulphoxide (DMSO) is a solvent often used to dissolve compounds applied to the inner ear; however, little is known about its potential cytotoxic side effects. To address this question, we applied 0.1 to 6% DMSO for 24 h to cochlear organotypic cultures from postnatal day 3 rats and examined its cytotoxic effects. DMSO concentrations of 0.1% and 0.25% caused little or no damage. However, concentrations between 0.5 and 6% resulted in stereocilia damage, hair cell swelling and a dose-dependent loss of hair cells. Hair cell damage began in the basal turn of the cochlea and spread towards the apex with increasing concentration. Surprisingly, DMSO-induced damage was greater for inner hair cells than outer hair cell whereas nearby supporting cells were largely unaffected. Most hair cell death was associated with nuclear shrinkage and fragmentation, morphological features consistent with apoptosis. DMSO treatment induced TUNEL positive staining in many hair cells and activated both initiator caspase-9 and caspase-8 and executioner caspase-3; this suggests that apoptosis is initiated by both intrinsic mitochondrial and extrinsic membrane cell death signaling pathways. PMID:18207679

Uptake and cytotoxic effects of multi-walled carbon nanotubes in human bronchial epithelial cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hirano, Seishiro, E-mail: seishiro@nies.go.j; Fujitani, Yuji; Furuyama, Akiko

Carbon nanotubes (CNT) are cytotoxic to several cell types. However, the mechanism of CNT toxicity has not been fully studied, and dosimetric analyses of CNT in the cell culture system are lacking. Here, we describe a novel, high throughput method to measure cellular uptake of CNT using turbimetry. BEAS-2B, a human bronchial epithelial cell line, was used to investigate cellular uptake, cytotoxicity, and inflammatory effects of multi-walled CNT (MWCNT). The cytotoxicity of MWCNT was higher than that of crocidolite asbestos in BEAS-2B cells. The IC{sub 50} of MWCNT was 12 {mu}g/ml, whereas that of asbestos (crocidolite) was 678 {mu}g/ml. Overmore » the course of 5 to 8 h, BEAS-2B cells took up 17-18% of the MWCNT when they were added to the culture medium at a concentration of 10 {mu}g/ml. BEAS-2B cells were exposed to 2, 5, or 10 {mu}g/ml of MWCNT, and total RNA was extracted for cytokine cDNA primer array assays. The culture supernatant was collected for cytokine antibody array assays. Cytokines IL-6 and IL-8 increased in a dose dependent manner at both the mRNA and protein levels. Migration inhibitory factor (MIF) also increased in the culture supernatant in response to MWCNT. A phosphokinase array study using lysates from BEAS-2B cells exposed to MWCNT indicated that phosphorylation of p38, ERK1, and HSP27 increased significantly in response to MWCNT. Results from a reporter gene assays using the NF-{kappa}B or AP-1 promoter linked to the luciferase gene in transiently transfected CHO-KI cells revealed that NF-{kappa}B was activated following MWCNT exposure, while AP-1 was not changed. Collectively, MWCNT activated NF-{kappa}B, enhanced phosphorylation of MAP kinase pathway components, and increased production of proinflammatory cytokines in human bronchial epithelial cells.« less

Silymarin attenuated paraquat-induced cytotoxicity in macrophage by regulating Trx/TXNIP complex, inhibiting NLRP3 inflammasome activation and apoptosis.

PubMed

Liu, Zhenning; Sun, Mingli; Wang, Yu; Zhang, Lichun; Zhao, Hang; Zhao, Min

2018-02-01

Oxidative stress and inflammation are involved in paraquat-induced cytotoxicity. Silymarin can exert a potent antioxidative and anti-inflammatory effect in various pathophysiological processes. The aim of this current study is to explore the protective effect and potential mechanism of silymarin in paraquat-induced macrophage injury. Cells were pretreated with different doses of silymarin for 3h before exposure to paraquat. At 24h after exposure to paraquat, the paraquat-induced cytotoxicity to macrophage was measured via the MTT assay and LDH release. The levels of intracellular reactive oxygen species, GSH-Px, SOD, and lipid peroxidation product malondialdehyde were measured to evaluate the oxidative effect of paraquat. NLRP3 inflammasome and cytokines secretion in macrophage exposed to paraquat at 24h were measured via immunofluorescence microscopy, western blot or Elisa. Our results revealed that paraquat could dramatically cause cytotoxicity and reactive oxygen species generation, enhance TXNIP expression, and induce NLRP3 inflammasome activation and cytokines secretion. The pretreatment with silymarin could remarkably reduce the cytotoxicity, promote the expression of Trx and antioxidant enzymes, and suppress the TXNIP and NLRP3 inflammasome activation. In conclusion, silymarin attenuated paraquat-induced cytotoxicity in macrophage by inhibiting oxidative stress, NLRP3 inflammasome activation, cytokines secretion and apoptosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prevention effect of rare ginsenosides against stress-hormone induced MTOC amplification

PubMed Central

Lee, Jee-Hyun; Cheong, Kyu Jin; Jung, Youn-Sang; Woo, Tae-Gyun; Yoon, Min-Ho; Oh, Ah-Young; Kang, So-Mi; Lee, Chunghui; Sun, Hokeun; Hwang, Jihwan; Song, Gyu-Yong; Park, Bum-Joon

2016-01-01

Stress has been suggested as one of important cause of human cancer without molecular biological evidence. Thus, we test the effect of stress-related hormones on cell viability and mitotic fidelity. Similarly to estrogen, stress hormone cortisol and its relative cortisone increase microtubule organizing center (MTOC) number through elevated expression of γ-tubulin and provide the Taxol resistance to human cancer cell lines. However, these effects are achieved by glucocorticoid hormone receptor (GR) but not by estrogen receptor (ER). Since ginsenosides possess steroid-like structure, we hypothesized that it would block the stress or estrogen-induced MTOC amplification and Taxol resistance. Among tested chemicals, rare ginsenoside, CSH1 (Rg6) shows obvious effect on inhibition of MTOC amplification, γ-tubulin induction and Taxol resistance. Comparing to Fulvestant (FST), ER-α specific inhibitor, this chemical can block the cortisol/cortisone-induced MTOC deregulation as well as ER-α signaling. Our results suggest that stress hormone induced tumorigenesis would be achieved by MTOC amplification, and CSH1 would be useful for prevention of stress-hormone or steroid hormone-induced chromosomal instability. PMID:27147573

Analysis of the Effects of Cell Stress and Cytotoxicity on In ...

EPA Pesticide Factsheets

Chemical toxicity can arise from disruption of specific biomolecular functions or through more generalized cell stress and cytotoxicity-mediated processes. Here, concentration-dependent responses of 1063 chemicals including pharmaceuticals, natural products, pesticidals, consumer, and industrial chemicals across a diverse battery of 821 in vitro assay endpoints from 7 high-throughput assay technology platforms were analyzed in order to better distinguish between these types of activities. Both cell-based and cell-free assays showed a rapid increase in the frequency of responses at concentrations where cell stress / cytotoxicity responses were observed in cell-based assays. Chemicals that were positive on at least two viability/cytotoxicity assays within the concentration range tested (typically up to 100 M) activated a median of 12% of assay endpoints while those that were not cytotoxic in this concentration range activated 1.3% of the assays endpoints. The results suggest that activity can be broadly divided into: (1) specific biomolecular interactions against one or more targets (e.g., receptors or enzymes) at concentrations below which overt cytotoxicity-associated activity is observed; and (2) activity associated with cell stress or cytotoxicity, which may result from triggering of specific cell stress pathways, chemical reactivity, physico-chemical disruption of proteins or membranes, or broad low-affinity non-covalent interactions. Chemicals showing a g

Suppressive effects of 3-methylcholanthrene on the in vitro antitumor activity of naturally cytotoxic cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lill, P.H.; Gangemi, D.

1986-01-01

Transient suppression of splenic natural killer (NK), natural cytotoxic (NC) and peritoneal macrophage cytotoxicity was observed following a single injection of 3-methylcholanthrene (3-MC) into C3H/HeN mice. Natural killer cell activity was depressed by 30-60% 4-6 d after injection of 1.0 mg 3-MC. Levels of NK reactivity returned to normal 8 d post 3-MC injection, and no suppression of natural killing was seen when tested 6 wk after 3-MC treatment. 3-MC did not affect propionibacterium acnes augmentation of NK cell activity when tested both 6 d and 6 wk after carcinogen injection. The results indicate that the observed suppression of naturallymore » cytotoxic cells may not be important in allowing 3-MC-induced tumors to grow, since suppression is not long-lasting. Therefore, any effect on tumor growth mediated by a suppression of naturally cytotoxic cells would have to be exerted at the earliest stages of tumor development.« less

Spirulina Extract Enhanced a Protective Effect in Type 1 Diabetes by Anti-Apoptosis and Anti-ROS Production

PubMed Central

Lee, Jiyeong; Park, Arum; Kim, Mi Jeong; Lim, Hee-Joung; Rha, Young-Ah

2017-01-01

Interest in the nutritional value and pharmacological activities of blue-green algae has gradually increased. Spirulina extracts show protective effects against apoptosis and inflammatory damage in various cell types. Here, we investigated the protective effects of extracts from Spirulina maxima in a cytokine-mediated type 1 diabetes model in vitro and in streptozotocin-induced diabetic Wistar rats in vivo. Interleukin-1β and interferon-gamma induced substantial cytotoxicity to RINm5F rat insulinoma cells, increasing nitric oxide (NO) production, nuclear factor-kappa B (NF-κB) activity, the expression of endoplasmic reticulum (ER) stress genes, and activation of mitogen-activated protein kinases and key genes related apoptosis. However, the cytotoxicity of cytokines was significantly attenuated by Spirulina extract, which effectively prevented NO production by inhibiting the synthesis of cytokine-activated NO synthase (iNOS), and apoptosis was suppressed. These results suggest that Spirulina extract might be effective to preserve the viability and function of pancreatic β-cells against cytotoxic conditions. Moreover, diabetic mice orally administered Spirulina extract showed decreased glucose levels, increased insulin, and improvement in liver enzyme markers. The antioxidant effect of Spirulina extract may be helpful in treating type 1 diabetes by enhancing the survival, and reducing or delaying cytokine-mediated β-cells destruction. PMID:29244751

Antibacterial Effect of Copaifera duckei Dwyer Oleoresin and Its Main Diterpenes against Oral Pathogens and Their Cytotoxic Effect

PubMed Central

Abrão, Fariza; Alves, Jessica A.; Andrade, Gessica; de Oliveira, Pollyanna F.; Ambrósio, Sérgio R.; Veneziani, Rodrigo C. S.; Tavares, Denise C.; Bastos, Jairo K.; Martins, Carlos H. G.

2018-01-01

This study evaluates the antibacterial activity of the Copaifera duckei Dwyer oleoresin and two isolated compounds [eperu-8(20)-15,18-dioic acid and polyalthic acid] against bacteria involved in primary endodontic infections and dental caries and assesses the cytotoxic effect of these substances against a normal cell line. MIC and MBC assays pointed out the most promising metabolites for further studies on bactericidal kinetics, antibiofilm activity, and synergistic antibacterial action. The oleoresin and polyalthic acid but not eperu-8(20)-15,18-dioic provided encouraging MIC and MBC results at concentrations lower than 100 μg mL−1. The oleoresin and polyalthic acid activities depended on the evaluated strain. A bactericidal effect on Lactobacillus casei (ATCC 11578 and clinical isolate) emerged before 8 h of incubation. For all the tested bacteria, the oleoresin and polyalthic acid inhibited biofilm formation by at least 50%. The oleoresin and polyalthic acid gave the best activity against Actinomyces naeslundii (ATCC 19039) and L. casei (ATCC 11578), respectively. The synergistic assays combining the oleoresin or polyalthic acid with chlorhexidine did not afford interesting results. We examined the cytotoxicity of C. duckei oleoresin, eperu-8(20)-15,18-dioic acid, and polyalthic acid against Chinese hamster lung fibroblasts. The oleoresin and polyalthic acid were cytotoxic at concentrations above 78.1 μg mL−1, whereas eperu-8(20)-15,18-dioic displayed cytotoxicity at concentrations above 312.5 μg mL−1. In conclusion, the oleoresin and polyalthic acid are potential sources of antibacterial agents against bacteria involved in primary endodontic infections and dental caries in both the sessile and the planktonic modes at concentrations that do not cause cytotoxicity. PMID:29515530

Cytotoxic T lymphocyte antigen 4 decreases humoral and cellular immunity by adenovirus to enhance target GFP gene transfer in C57BL/6 mice.

PubMed

Bai, Dou; Zhu, Wei; Zhang, Yu; Long, Ling; Zhu, Naishuo

2015-01-01

Adenoviruses (Ad) are once potential and promising vectors for gene delivery, but the immunogenicity attenuates its transfer efficiency. Cytotoxic T lymphocyte antigen 4 (CTLA-4) can inhibit T cell immunity. Thus, we aimed to study the effect of CTLA-4 in the process of Ad-mediated gene transfer. The C57BL/6 mice were injected by Ad vectors at twice, and CTLA-4 was administrated after the first Ad injection. Then, the CD3(+)CD4(+) T cells and circulating levels of IL-2, IL-4, and anti-Ad IgG were decreased by CTLA-4, while Ad generated immune responses. The green fluorescence protein (GFP) expressions of tissues were enhanced by CTLA-4 till injection of Ad at twice. Our results indicate that CTLA-4 can inhibit humoral and cellular immunity by adenovirus generation to enhance GFP delivery, and provide a potential way to assist in Ad-mediated gene transfer.

D-piece modifications of the hemiasterlin analog HTI-286 produce potent tubulin inhibitors.

PubMed

Zask, Arie; Birnberg, Gary; Cheung, Katherine; Kaplan, Joshua; Niu, Chuan; Norton, Emily; Yamashita, Ayako; Beyer, Carl; Krishnamurthy, Girija; Greenberger, Lee M; Loganzo, Frank; Ayral-Kaloustian, Semiramis

2004-08-16

Modifications of the D-piece carboxylic acid group of the hemiasterlin analog HTI-286 gave tubulin inhibitors which were potent cytotoxic agents in taxol resistant cell lines expressing P-glycoprotein. Amides derived from proline had potency comparable to HTI-286. Reduction of the carboxylic acid to ketones and alcohols or its conversion to acidic heterocycles also gave potent analogs. Synthetic modifications of the carboxylic acid could be carried out selectively using a wide range of synthetic reagents. Proline analog 3 was found to be effective in a human xenograft model in athymic mice.

Poly(ADP-ribose) polymerase-independent potentiation of nitrosourea cytotoxicity by 3-aminobenzamide in human malignant glioma cells.

PubMed

Winter, S; Weller, M

2000-06-16

Poly(ADP-ribose) polymerase is a zinc-finger DNA-binding protein that detects specifically DNA strand breaks generated by genotoxic agents and is thought to be involved in DNA repair. Here, we examined the effects of 3-aminobenzamide, a poly(ADP-ribose) polymerase inhibitor, on the chemosensitivity of human malignant glioma cells. 3-Aminobenzamide selectively potentiated the cytotoxicity of the nitrosoureas, nimustine, carmustine and lomustine in 10 of 12 human malignant glioma cell lines. In contrast, 3-aminobenzamide did not modulate the cytotoxic effects of doxorubicine, teniposide, vincristine, camptothecin or cytarabine. The nitrosoureas did not induce poly(ADP-ribose) polymerase activity in the glioma cells. Ectopic expression of truncated poly(ADP-ribose) polymerase containing the poly(ADP-ribose) polymerase DNA-binding domain, which acts as a dominant-negative mutant, in LN-18 or LN-229 cells did not alter the 3-aminobenzamide effect on nitrosourea-mediated cytotoxicity. Thus, 3-aminobenzamide may target another nicotinamide adenine dinucleotide (NAD)-requiring enzyme, but not poly(ADP-ribose) polymerase, when enhancing nitrosourea cytotoxicity in human malignant glioma cells. Carmustine cytotoxicity was associated with a G2/M arrest. Coexposure to carmustine and 3-aminobenzamide overcame this G2/M arrest in T98G cells, which are sensitized to carmustine by 3-aminobenzamide, but not in U251MG cells, which are refractory to 3-aminobenzamide-mediated sensitization to carmustine. Thus, 3-aminobenzamide-mediated sensitization to carmustine cytotoxicity may result from interference with the stable G2/M arrest response to carmustine in human glioma cells.

Biological effects of a de novo designed myxoma virus peptide analogue: evaluation of cytotoxicity on tumor cells.

PubMed

Istivan, Taghrid S; Pirogova, Elena; Gan, Emily; Almansour, Nahlah M; Coloe, Peter J; Cosic, Irena

2011-01-01

The Resonant Recognition Model (RRM) is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV) proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity. The analogue RRM-MV was designed by RRM as a linear 18 aa 2.3 kDa peptide. The biological activity of this computationally designed peptide analogue against cancer and normal cell lines was investigated. The cellular cytotoxicity effects were confirmed by confocal immunofluorescence microscopy, by measuring the levels of cytoplasmic lactate dehydrogenase (LDH) and by Prestoblue cell viability assay for up to 72 hours in peptide treated and non-treated cell cultures. Our results revealed that RRM-MV induced a significant dose and time-dependent cytotoxic effect on murine and human cancer cell lines. Yet, when normal murine cell lines were similarly treated with RRM-MV, no cytotoxic effects were observed. Furthermore, the non-bioactive RRM designed peptide RRM-C produced negligible cytotoxic effects on these cancer and normal cell lines when used at similar concentrations. The presence/absence of phosphorylated Akt activity in B16F0 mouse melanoma cells was assessed to indicate the possible apoptosis signalling pathway that could be affected by the peptide treatment. So far, Akt activity did not seem to be significantly affected by RRM-MV as is the case for the original viral protein. Our findings indicate the successful application of the RRM concept to design a bioactive peptide analogue (RRM-MV) with cytotoxic effects on tumor cells only. This 2.345 kDa peptide analogue to a 49 kDa viral protein may be suitable to be developed as a potential cancer therapeutic. These results also open a new direction to the rational design of therapeutic agents for future cancer treatment.

Biological Effects of a De Novo Designed Myxoma Virus Peptide Analogue: Evaluation of Cytotoxicity on Tumor Cells

PubMed Central

Istivan, Taghrid S.; Pirogova, Elena; Gan, Emily; Almansour, Nahlah M.; Coloe, Peter J.; Cosic, Irena

2011-01-01

Background The Resonant Recognition Model (RRM) is a physico-mathematical model that interprets protein sequence linear information using digital signal processing methods. In this study the RRM concept was employed for structure-function analysis of myxoma virus (MV) proteins and the design of a short bioactive therapeutic peptide with MV-like antitumor/cytotoxic activity. Methodology/Principal Findings The analogue RRM-MV was designed by RRM as a linear 18 aa 2.3 kDa peptide. The biological activity of this computationally designed peptide analogue against cancer and normal cell lines was investigated. The cellular cytotoxicity effects were confirmed by confocal immunofluorescence microscopy, by measuring the levels of cytoplasmic lactate dehydrogenase (LDH) and by Prestoblue cell viability assay for up to 72 hours in peptide treated and non-treated cell cultures. Our results revealed that RRM-MV induced a significant dose and time-dependent cytotoxic effect on murine and human cancer cell lines. Yet, when normal murine cell lines were similarly treated with RRM-MV, no cytotoxic effects were observed. Furthermore, the non-bioactive RRM designed peptide RRM-C produced negligible cytotoxic effects on these cancer and normal cell lines when used at similar concentrations. The presence/absence of phosphorylated Akt activity in B16F0 mouse melanoma cells was assessed to indicate the possible apoptosis signalling pathway that could be affected by the peptide treatment. So far, Akt activity did not seem to be significantly affected by RRM-MV as is the case for the original viral protein. Conclusions/Significance Our findings indicate the successful application of the RRM concept to design a bioactive peptide analogue (RRM-MV) with cytotoxic effects on tumor cells only. This 2.345 kDa peptide analogue to a 49 kDa viral protein may be suitable to be developed as a potential cancer therapeutic. These results also open a new direction to the rational design of therapeutic

Triggering of the TRPV2 channel by cannabidiol sensitizes glioblastoma cells to cytotoxic chemotherapeutic agents.

PubMed

Nabissi, Massimo; Morelli, Maria Beatrice; Santoni, Matteo; Santoni, Giorgio

2013-01-01

The aggressive behavior of Glioblastoma multiforme (GBM) is mainly due to high invasiveness and proliferation rate as well as to high resistance to standard chemotherapy. Several chemotherapeutic agents like temozolomide (TMZ), carmustine (BCNU) or doxorubicin (DOXO) have been employed for treatment of GBM, but they display limited efficacy. Therefore, it is important to identify new treatment modalities to improve therapeutic effects and enhance GBM chemosensitivity. Recently, activation of the transient receptor potential vanilloid type 2 (TRPV2) has been found to inhibit human GBM cell proliferation and overcome BCNU resistance of GBM cells. Herein, we evaluated the involvement of cannabidiol (CBD)-induced TRPV2 activation, in the modulation of glioma cell chemosensitivity to TMZ, BCNU and DOXO. We found that CBD increases TRPV2 expression and activity. CBD by triggering TRPV2-dependent Ca(2+) influx increases drug uptake and synergizes with cytotoxic agents to induce apoptosis of glioma cells, whereas no effects were observed in normal human astrocytes. Moreover, as the pore region of transient receptor potential (TRP) channels is critical for ion channel permeation, we demonstrated that deletion of TRPV2 poredomain inhibits CBD-induced Ca(2+) influx, drug uptake and cytotoxic effects. Overall, we demonstrated that co-administration of cytotoxic agents together with the TRPV2 agonist CBD increases drug uptake and parallelly potentiates cytotoxic activity in human glioma cells.

Cytotoxic and apoptotic effects of bortezomib and gefitinib compared to alkylating agents on human glioblastoma cells.

PubMed

Pédeboscq, Stéphane; L'Azou, Béatrice; Passagne, Isabelle; De Giorgi, Francesca; Ichas, François; Pometan, Jean-Paul; Cambar, Jean

2008-01-01

Glioblastoma is a malignant astrocytic tumor with a median survival of about 12 months for which new therapeutic strategies are required. We therefore examined the cytotoxicity of anticancer drugs with different mechanisms of action on two human glioblastoma cell lines expressing various levels of EGFR (epidermal growth factor receptor). Apoptosis induced by these anticancer agents was evaluated by flow cytometry. The cytotoxicity of alkylating drugs followed a dose-effect curve and cytotoxicity index values were lower with carboplatin than with BCNU and temozolomide. Anti-EGFR gefitinib (10 microM) cytotoxicity on DBTRG.05-MG expressing high levels of EGFR was significantly higher than on U87-MG expressing low levels of EGFR. Carboplatin and temozolomide cytotoxicity was potentiated with the addition of gefitinib on DBTRG.05-MG. Among the anticancer agents tested, the proteasome inhibitor bortezomib was the most cytotoxic with very low IC50 on the two cell lines. Moreover, all anticancer drugs tested induced apoptosis in a concentration-dependent manner. Bortezomib proved to be a more potent inductor of apoptosis than gefitinib and alkylating agents. These results show the efficacy of bortezomib and of the association between conventional chemotherapy and gefitinib on glioblastoma cells and therefore suggest the interest of these molecules in the treatment of glioblastoma.

The effect of poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity.

PubMed

Yan, Fei; Zhang, Chao; Zheng, Yi; Mei, Lin; Tang, Lina; Song, Cunxian; Sun, Hongfan; Huang, Laiqiang

2010-02-01

The aim of this work was to investigate the effect of triblock copolymer poloxamer 188 on nanoparticle morphology, size, cancer cell uptake, and cytotoxicity. Docetaxel-loaded nanoparticles were prepared by oil-in-water emulsion/solvent evaporation technique using biodegradable poly(lactic-co-glycolic acid) (PLGA) with or without addition of poloxamer 188, respectively. The resulting nanoparticles were found to be spherical with a rough and porous surface. The nanoparticles had an average size of around 200 nm with a narrow size distribution. The in vitro drug-release profile of both nanoparticle formulations showed a biphasic release pattern. An increased level of uptake of PLGA/poloxamer 188 nanoparticles in the docetaxel-resistant MCF-7 TAX30 human breast cancer cell line could be found in comparison with that of PLGA nanoparticles. In addition, the docetaxel-loaded PLGA/poloxamer 188 nanoparticles achieved a significantly higher level of cytotoxicity than that of docetaxel-loaded PLGA nanoparticles and Taxotere (P < .05). In conclusion, the results showed advantages of docetaxel-loaded PLGA nanoparticles incorporated with poloxamer 188 compared with the nanoparticles without incorporation of poloxamer 188 in terms of sustainable release and efficacy in breast cancer chemotherapy. The effects of poloxamer 188, a triblock copolymer were studied on nanoparticle morphology, size, cancer cell uptake and cytotoxicity. An increased level of uptake of PLGA/poloxamer 188 nanoparticles in resistant human breast cancer cell line was demonstrated, resulting in a significantly higher level of cytotoxicity. Copyright 2010 Elsevier Inc. All rights reserved.

Withania somnifera Root Extract Has Potent Cytotoxic Effect against Human Malignant Melanoma Cells

PubMed Central

Halder, Babli; Singh, Shruti; Thakur, Suman S.

2015-01-01

In Ayurveda, Withania somnifera is commonly known as Ashwagandha, its roots are specifically used in medicinal and clinical applications. It possesses numerous therapeutic actions which include anti-inflammatory, sedative, hypnotic and narcotic. Extracts from this plant have been reported for its anticancer properties. In this study we evaluated for the first time, the cytotoxic effect of Withania root extract on human malignant melanoma A375 cells. The crude extract of Withania was tested for cytotoxicity against A375 cells by MTT assay. Cell morphology of treated A375 cells was visualized through phase contrast as well as fluorescence microscopy. Agarose gel electrophoresis was used to check DNA fragmentation of the crude extract treated cells. Crude extract of Withania root has the potency to reduce viable cell count in dose as well as time dependent manner. Morphological change of the A375 cells was also observed in treated groups in comparison to untreated or vehicle treated control. Apoptotic body and nuclear blebbing were observed in DAPI stained treated cells under fluorescence microscope. A ladder of fragmented DNA was noticed in treated cells. Thus it might be said that the crude water extract of Withania somnifera has potent cytotoxic effect on human malignant melanoma A375 cells. PMID:26334881

Green vegetables, red meat and colon cancer: chlorophyll prevents the cytotoxic and hyperproliferative effects of haem in rat colon.

PubMed

de Vogel, Johan; Jonker-Termont, Denise S M L; van Lieshout, Esther M M; Katan, Martijn B; van der Meer, Roelof

2005-02-01

Diets high in red meat and low in green vegetables are associated with increased colon cancer risk. This association might be partly due to the haem content of red meat. In rats, dietary haem is metabolized in the gut to a cytotoxic factor that increases colonic cytotoxicity and epithelial proliferation. Green vegetables contain chlorophyll, a magnesium porphyrin structurally analogous to haem. We studied whether green vegetables inhibit the unfavourable colonic effects of haem. First, rats were fed a purified control diet or purified diets supplemented with 0.5 mmol haem/kg, spinach (chlorophyll concentration 1.2 mmol/kg) or haem plus spinach (n = 8/group) for 14 days. In a second experiment we also studied a group that received haem plus purified chlorophyll (1.2 mmol/kg). Cytotoxicity of faecal water was determined with a bioassay and colonic epithelial cell proliferation was quantified in vivo by [methyl-(3)H]thymidine incorporation into newly synthesized DNA. Exfoliation of colonocytes was measured as the amount of rat DNA in faeces. In both studies haem increased cytotoxicity of the colonic contents approximately 8-fold and proliferation of the colonocytes almost 2-fold. Spinach or an equimolar amount of chlorophyll supplement in the haem diet inhibited these haem effects completely. Haem clearly inhibited exfoliation of colonocytes, an effect counteracted by spinach and chlorophyll. Finally, size exclusion chromatography showed that chlorophyll prevented formation of the cytotoxic haem metabolite. We conclude that green vegetables may decrease colon cancer risk because chlorophyll prevents the detrimental, cytotoxic and hyperproliferative colonic effects of dietary haem.

Cytotoxic effects in 3T3-L1 mouse and WI-38 human fibroblasts following 72 hour and 7 day exposures to commercial silica nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stępnik, Maciej, E-mail: mstep@imp.lodz.pl; Arkusz, Joanna; Smok-Pieniążek, Anna

The potential toxic effects in murine (3T3-L1) and human (WI-38) fibroblast cell lines of commercially available silica nanoparticles (NPs), Ludox CL (nominal size 21 nm) and CL-X (nominal size of 30 nm) were investigated with particular attention to the effect over long exposure times (the tests were run after 72 h exposure up to 7 days). These two formulations differed in physico-chemical properties and showed different stabilities in the cell culture medium used for the experiments. Ludox CL silica NPs were found to be cytotoxic only at the higher concentrations to the WI-38 cells (WST-1 and LDH assays) but notmore » to the 3T3-L1 cells, whereas the Ludox CL-X silica NPs, which were less stable over the 72 h exposure, were cytotoxic to both cell lines in both assays. In the clonogenic assay both silica NPs induced a concentration dependent decrease in the surviving fraction of 3T3-L1 cells, with the Ludox CL-X silica NPs being more cytotoxic. Cell cycle analysis showed a trend indicating alterations in both cell lines at different phases with both silica NPs tested. Buthionine sulfoximine (γ-glutamylcysteine synthetase inhibitor) combined with Ludox CL-X was found to induce a strong decrease in 3T3-L1 cell viability which was not observed for the WI-38 cell line. This study clearly indicates that longer exposure studies may give important insights on the impact of nanomaterials on cells. However, and especially when investigating nanoparticle effects after such long exposure, it is fundamental to include a detailed physico-chemical characterization of the nanoparticles and their dispersions over the time scale of the experiment, in order to be able to interpret eventual impacts on cells. -- Highlights: ► Ludox CL silica NPs are cytotoxic to WI-38 fibroblasts but not to 3T3-L1 fibroblasts. ► Ludox CL-X silica NPs are cytotoxic to both cell lines. ► In clonogenic assay both silica NPs induce cytotoxicity, higher for CL-X silica. ► Cell cycle analysis

Targeted Modification of Mitochondrial ROS Production Converts High Glucose-Induced Cytotoxicity to Cytoprotection: Effects on Anesthetic Preconditioning.

PubMed

Sedlic, Filip; Muravyeva, Maria Y; Sepac, Ana; Sedlic, Marija; Williams, Anna Marie; Yang, Meiying; Bai, Xiaowen; Bosnjak, Zeljko J

2017-01-01

Contradictory reports on the effects of diabetes and hyperglycemia on myocardial infarction range from cytotoxicity to cytoprotection. The study was designed to investigate acute effects of high glucose-driven changes in mitochondrial metabolism and osmolarity on adaptive mechanisms and resistance to oxidative stress of isolated rat cardiomyocytes. We examined the effects of high glucose on several parameters of mitochondrial bioenergetics, including changes in oxygen consumption, mitochondrial membrane potential, and NAD(P)H fluorometry. Effects of high glucose on the endogenous cytoprotective mechanisms elicited by anesthetic preconditioning (APC) and the mediators of cell injury were also tested. These experiments included real-time measurements of reactive oxygen species (ROS) production and mitochondrial permeability transition pore (mPTP) opening in single cells by laser scanning fluorescence confocal microscopy, and cell survival assay. High glucose rapidly enhanced mitochondrial energy metabolism, observed by increase in NAD(P)H fluorescence intensity, oxygen consumption, and mitochondrial membrane potential. This substantially elevated production of ROS, accelerated opening of the mPTP, and decreased survival of cells exposed to oxidative stress. Abrogation of high glucose-induced mitochondrial hyperpolarization with 2,4 dinitrophenol (DNP) significantly, but not completely, attenuated ROS production to a level similar to hyperosmotic mannitol control. DNP treatment reversed high glucose-induced cytotoxicity to cytoprotection. Hyperosmotic mannitol treatment also induced cytoprotection. High glucose abrogated APC-induced mitochondrial depolarization, delay in mPTP opening and cytoprotection. In conclusion, high glucose-induced mitochondrial hyperpolarization abolishes APC and augments cell injury. Attenuation of high glucose-induced ROS production by eliminating mitochondrial hyperpolarization protects cardiomyocytes. J. Cell. Physiol. 232: 216-224, 2017

Synthesis of non-cytotoxic poly(ester-amine) dendrimers as potential solubility enhancers for drugs: methotrexate as a case study.

PubMed

Soto-Castro, Delia; Cruz-Morales, Jorge A; Ramírez Apan, María Teresa; Guadarrama, Patricia

2010-11-09

This study describes the synthesis of two new families of dendrimers based on the esterification of N-alkylated 3-amine-1-propanol with two different cores, adipic acid (1st and 2nd generations) and ethylenediamine (generation 1.5), both with carboxylic acid end groups, offering a wide variety of further modifications at the periphery. According to the cytotoxic evaluation of the dendrimers and their possible degradation products within cell lines, these materials could be considered as innocuous. In preliminary studies, the synthesized dendrimers proved to be potential enhancers of solubility of highly hydrophobic drugs, like methotrexate, widely used in chemotherapy.

Evaluation of a UCMK/dCK fusion enzyme for gemcitabine-mediated cytotoxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, Adam J.; Brown, Melissa N.; Black, Margaret E., E-mail: blackm@vetmed.wsu.edu

2011-12-09

Highlights: Black-Right-Pointing-Pointer Goal was to enhance dFdC cytotoxicity by the creation of a UCMK/dCK fusion enzyme. Black-Right-Pointing-Pointer The UCMK/dCK fusion enzyme possesses both native activities. Black-Right-Pointing-Pointer The fusion renders cells equally sensitive to dFdC relative to dCK expression alone. Black-Right-Pointing-Pointer Dual activities of fusion not sufficient to augment cell dFdC sensitivity in vitro. Black-Right-Pointing-Pointer Data may warrant the implementation of UCMK mutagenesis studies. -- Abstract: While gemcitabine (2 Prime -2 Prime -difluoro-2 Prime -deoxycytidine, dFdC) displays wide-ranging antineoplastic activity as a single agent, variable response rates and poor intracellular metabolism often limit its clinical efficacy. In an effort to enhancemore » dFdC cytotoxicity and help normalize response rates, we created a bifunctional fusion enzyme that combines the enzymatic activities of deoxycytidine kinase (dCK) and uridine/cytidine monophosphate kinase (UCMK) in a single polypeptide. Our goal was to evaluate whether the created fusion could induce beneficial, functional changes toward dFdC, expedite dFdC conversion to its active antimetabolites and consequently amplify cell dFdC sensitivity. While kinetic analyses revealed the UCMK/dCK fusion enzyme to possess both native activities, the fusion rendered cells sensitive to the cytotoxic effects of dFdC at the same level as dCK expression alone. These results suggest that increased wild-type UCMK expression does not provide a significant enhancement in dFdC-mediated cytotoxicity and may warrant the implementation of studies aimed at engineering UCMK variants with improved activity toward gemcitabine monophosphate.« less

Nanosecond pulsed electric field (nsPEF) enhance cytotoxicity of cisplatin to hepatocellular cells by microdomain disruption on plasma membrane.

PubMed

Yin, Shengyong; Chen, Xinhua; Xie, Haiyang; Zhou, Lin; Guo, Danjing; Xu, Yuning; Wu, Liming; Zheng, Shusen

2016-08-15

Previous studies showed nanosecond pulsed electric field (nsPEF) can ablate solid tumors including hepatocellular carcinoma (HCC) but its effect on cell membrane is not fully understood. We hypothesized nsPEF disrupt the microdomains on outer-cellular membrane with direct mechanical force and as a result the plasma membrane permeability increases to facilitate the small molecule intake. Three HCC cells were pulsed one pulse per minute, an interval longer than nanopore resealing time. The cationized ferritin was used to mark up the electronegative microdomains, propidium iodide (PI) for membrane permeabilization, energy dispersive X-ray spectroscopy (EDS) for the negative cell surface charge and cisplatin for inner-cellular cytotoxicity. We demonstrated that the ferritin marked-microdomain and negative cell surface charge were disrupted by nsPEF caused-mechanical force. The cell uptake of propidium and cytotoxicity of DNA-targeted cisplatin increased with a dose effect. Cisplatin gains its maximum inner-cellular cytotoxicity when combining with nsPEF stimulation. We conclude that nsPEF disrupt the microdomains on the outer cellular membrane directly and increase the membrane permeabilization for PI and cisplatin. The microdomain disruption and membrane infiltration changes are caused by the mechanical force from the changes of negative cell surface charge. Copyright © 2016 Elsevier Inc. All rights reserved.

Inhibition of the B7-H3 immune checkpoint limits tumor growth by enhancing cytotoxic lymphocyte function.

PubMed

Lee, Young-Hee; Martin-Orozco, Natalia; Zheng, Peilin; Li, Jing; Zhang, Peng; Tan, Haidong; Park, Hyun Jung; Jeong, Mira; Chang, Seon Hee; Kim, Byung-Seok; Xiong, Wei; Zang, Wenjuan; Guo, Li; Liu, Yang; Dong, Zhong-Jun; Overwijk, Willem W; Hwu, Patrick; Yi, Qing; Kwak, Larry; Yang, Zhiying; Mak, Tak W; Li, Wei; Radvanyi, Laszlo G; Ni, Ling; Liu, Dongfang; Dong, Chen

2017-08-01

The interaction between tumor and the immune system is still poorly understood. Significant clinical responses have been achieved in cancer patients treated with antibodies against the CTLA4 and PD-1/PD-L1 checkpoints; however, only a small portion of patients responded to the therapies, indicating a need to explore additional co-inhibitory molecules for cancer treatment. B7-H3, a member of the B7 superfamily, was previously shown by us to inhibit T-cell activation and autoimmunity. In this study, we have analyzed the function of B7-H3 in tumor immunity. Expression of B7-H3 was found in multiple tumor lines, tumor-infiltrating dendritic cells, and macrophages. B7-H3-deficient mice or mice treated with an antagonistic antibody to B7-H3 showed reduced growth of multiple tumors, which depended on NK and CD8 + T cells. With a putative receptor expressed by cytotoxic lymphocytes, B7-H3 inhibited their activation, and its deficiency resulted in increased cytotoxic lymphocyte function in tumor-bearing mice. Combining blockades of B7-H3 and PD-1 resulted in further enhanced therapeutic control of late-stage tumors. Taken together, our results indicate that the B7-H3 checkpoint may serve as a novel target for immunotherapy against cancer.

Bu-Zhong-Yi-Qi Decoction, the Water Extract of Chinese Traditional Herbal Medicine, Enhances Cisplatin Cytotoxicity in A549/DDP Cells through Induction of Apoptosis and Autophagy

PubMed Central

Xiong, Ying

2017-01-01

Cisplatin is one of the most active cytotoxic agents for non-small cell lung cancer (NSCLC) treatment. However, the development of cisplatin resistance is common. Bu-Zhong-Yi-Qi decoction (BZYQD), a Chinese traditional herbal medicine, is widely used for the enhancement of antitumor effect in other medications. In this study, we evaluated the effect and drug-resistance reversal mechanism of BZYQD combined with cisplatin on cisplatin-resistant A549/DDP cells. Our results showed that BZYQD exhibited direct cytotoxic and chemosensitizing effects. Cotreatment with BZYQD and cisplatin induced intrinsic apoptotic pathways which were measured by condensed nuclear chromatin, Annexin V/PI apoptosis assay, and apoptosis related proteins expression. In addition, cotreatment with BZYQD and cisplatin also activated autophagy, as indicated by an increase in LC3 puncta, classical autophagosomes and/or autolysosomes, and an accumulation of LC3-II and ATG7 protein. Finally, cotreatment with BZYQD and cisplatin resulted in the generation of ROS and scavenging ROS by NAC almost completely suppressing cell death. These results suggest that cotreatment with BZYQD and cisplatin might reverse cisplatin resistance by inducing ROS accumulation, which activates apoptosis and autophagy by oxidative stress. The combination of BZYQD and cisplatin may represent a novel approach in treatment for NSCLC and thus offer a new target for chemotherapy. PMID:28154825

Cytotoxic chalcones from some Indonesian Cryptocarya

NASA Astrophysics Data System (ADS)

Kurniadewi, F.; Syah, Y. M.; Juliawaty, L. D.; Hakim, E. H.; Koyama, K.; Kinoshita, K.

2017-07-01

Malignant tumors are one of the main causes of death in the world. Until now the search for cytotoxic (antitumor) compounds from nature, particularly from plants, is being a continuation activities. One group of plants that produce potential cytotoxic compounds is the Cryptocarya, one of the large genera of the Lauraceae family. As a part of our chemical and cytotoxic evaluation of the Cryptocarya species, we examined three species of Indonesian Cryptocarya. The sample of the wood of C. konishii hayata was collected from Cibodas Botanical Garden, West Java while the stem bark of C. phoebeopsis and C. cagayanensis were obtained from Sorong, Papua. Our investigation of flavonoid constituents on these species afforded three chalcone compounds i.e. desmethylinfectocaryone (1), infectocaryone (2) and cryptocaryone (3). The molecular structures of the isolated compounds were determined based on spectroscopic data, including UV, IR, 1D and 2D NMR. Cytotoxic effects of the compounds were evaluated using MTT [3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide] assay. Compound 1, 2 and 3 displayed strong cytotoxic properties (IC50 < 2 μg/mL) against Murine Leukemia P388 and HL 60 (blood premyelocytic leukemia) cells whereas 2 and 3 exhibited strong cytotoxicity properties against HCT116 (colon cancer). Cryptocaryone (3) also showed moderate cytotoxic properties (IC50 < 10 μg/mL) towards A549 (human lung adenocarcinoma epithelial) cells.

Evaluation of the cytotoxic and genotoxic effects of benchmark multi-walled carbon nanotubes in relation to their physicochemical properties.

PubMed

Louro, Henriqueta; Pinhão, Mariana; Santos, Joana; Tavares, Ana; Vital, Nádia; Silva, Maria João

2016-11-16

To contribute with scientific evidence to the grouping strategy for the safety assessment of multi-walled carbon nanotubes (MWCNTs), this work describes the investigation of the cytotoxic and genotoxic effects of four benchmark MWCNTs in relation to their physicochemical characteristics, using two types of human respiratory cells. The cytotoxic effects were analysed using the clonogenic assay and replication index determination. A 48h-exposure of cells revealed that NM-401 was the only cytotoxic MWCNT in both cell lines, but after 8-days exposure, the clonogenic assay in A549 cells showed cytotoxic effects for all the tested MWCNTs. Correlation analysis suggested an association between the MWCNTs size in cell culture medium and cytotoxicity. No induction of DNA damage was observed after any MWCNTs in any cell line by the comet assay, while the micronucleus assay revealed that both NM-401 and NM-402 were genotoxic in A549 cells. NM-401 and NM-402 are the two longest MWCNTs analyzed in this work, suggesting that length may be determinant for genotoxicity. No induction of micronuclei was observed in BBEAS-2Beas-2B cell line and the different effect in both cell lines is explained in view of the size-distribution of MWCNTs in the cell culture medium, rather than cell's specificities. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Cytotoxicity of silica-glass fiber reinforced composites.

PubMed

Meriç, Gökçe; Dahl, Jon E; Ruyter, I Eystein

2008-09-01

Silica-glass fiber reinforced polymers can be used for many kinds of dental applications. The fiber reinforcement enhances the mechanical properties of the polymers, and they have good esthetic attributes. There is good initial bonding of glass fibers to polymers via an interface made from silane coupling agents. The aim of this in vitro study was to determine the cytotoxicity of two polymers reinforced with two differently sized silica-glass fibers before and after thermal cycling. Cytotoxicity of the polymers without fibers was also evaluated. Two different resin mixtures (A and B) were prepared from poly(vinyl chloridecovinylacetate) powder and poly(methyl methacrylate) (PMMA) dissolved in methyl methacrylate and mixed with different cross-linking agents. The resin A contained the cross-linking agents ethylene glycol dimethacrylate and 1,4-butanediol dimethacrylate, and for resin B diethylene glycol dimethacrylate was used. Woven silica-glass fibers were used for reinforcement. The fibers were sized with either linear poly(butyl methacrylate)-sizing or cross-linking PMMA-sizing. Cytotoxicity was evaluated by filter diffusion test (ISO 7405:1997) of newly made and thermocycled test specimens. Extracts were prepared according to ISO 10993-12 from newly made and from thermocycled specimens and tested by the MTT assay. The results from the experiments were statistically analyzed by one-way ANOVA and Tukey's test (rho<0.05). The filter diffusion test disclosed no change in staining intensity at the cell-test sample contact area indicating non-cytotoxicity in all experimental groups. Cell viability assessed by MTT assay was more than 90% in all experimental groups. All are non-cytotoxic. It can be concluded that correctly processed heat polymerized silica-glass fiber reinforced polymers induced no cytotoxicity and that thermocycling did not alter this property.

Assessment of in vitro genotoxic and cytotoxic effects of flurbiprofen on human cultured lymphocytes.

PubMed

Timocin, Taygun; Ila, Hasan Basri; Dordu, Tuba; Husunet, Mehmet Tahir; Tazehkand, Mostafa Norizadeh; Valipour, Ebrahim; Topaktas, Mehmet

2016-01-01

Flurbiprofen is non-steroidal anti-inflammatory drug which is commonly used for its analgesic, antipyretic, and anti-inflammatory effects. The purpose of the study was to explore the genotoxic and cytotoxic effects of flurbiprofen in human cultured lymphocytes by sister chromatid exchange, chromosome aberration, and cytokinesis-blocked micronucleus tests. 10, 20, 30, and 40 μg/mL concentrations of flurbiprofen (solvent is DMSO) were used to treatment of human cultured lymphocytes at two different treatment periods (24 and 48 h). Flurbiprofen had no significant genotoxic effect in any of these tests. But exposing to flurbiprofen for 24 and 48 h led to significant decrease on proliferation index, mitotic index, and nuclear division index (NDI). Also, all decreases were concentration-dependent (except NDI at 24 h treatment period). Consequently, the findings of this research showed that flurbiprofen had cytotoxic effects in human blood lymphocytes.

Copper doping enhanced the oxidative stress-mediated cytotoxicity of TiO2 nanoparticles in A549 cells.

PubMed

Ahmad, J; Siddiqui, M A; Akhtar, M J; Alhadlaq, H A; Alshamsan, A; Khan, S T; Wahab, R; Al-Khedhairy, A A; Al-Salim, A; Musarrat, J; Saquib, Q; Fareed, M; Ahamed, M

2018-05-01

Physicochemical properties of titanium dioxide nanoparticles (TiO 2 NPs) can be tuned by doping with metals or nonmetals. Copper (Cu) doping improved the photocatalytic behavior of TiO 2 NPs that can be applied in various fields such as environmental remediation and nanomedicine. However, interaction of Cu-doped TiO 2 NPs with human cells is scarce. This study was designed to explore the role of Cu doping in cytotoxic response of TiO 2 NPs in human lung epithelial (A549) cells. Characterization data demonstrated the presence of both TiO 2 and Cu in Cu-doped TiO 2 NPs with high-quality lattice fringes without any distortion. The size of Cu-doped TiO 2 NPs (24 nm) was lower than pure TiO 2 NPs (30 nm). Biological results showed that both pure and Cu-doped TiO 2 NPs induced cytotoxicity and oxidative stress in a dose-dependent manner. Low mitochondrial membrane potential and higher caspase-3 enzyme (apoptotic markers) activity were also observed in A549 cells exposed to pure and Cu-doped TiO 2 NPs. We further observed that cytotoxicity caused by Cu-doped TiO 2 NPs was higher than pure TiO 2 NPs. Moreover, antioxidant N-acetyl cysteine effectively prevented the reactive oxygen species generation, glutathione depletion, and cell viability reduction caused by Cu-doped TiO 2 NPs. This is the first report showing that Cu-doped TiO 2 NPs induced cytotoxicity and oxidative stress in A549 cells. This study warranted further research to explore the role of Cu doping in toxicity mechanisms of TiO 2 NPs.

Fish oil feeding enhances lymphocyte proliferation but impairs virus-specific T lymphocyte cytotoxicity in mice following challenge with influenza virus

PubMed Central

Byleveld, M; Pang, G T; Clancy, R L; Roberts, D C K

2000-01-01

The effect of a fish oil diet on virus-specific cytotoxicity and lymphocyte proliferation was investigated. Mice were fed fish oil (17 g fish oil and 3 g sunflower/100 g) or beef tallow (17 g tallow and 3 g sunflower/100 g) diets for 14 days before intranasal challenge with influenza virus. At day 5 after infection, lung virus-specific T lymphocyte, but not macrophage or natural killer (NK) cell, cytotoxicity was significantly lower in mice fed fish oil, while bronchial lymph node cell proliferation to virus was significantly higher. In mice fed fish oil, spleen cell proliferation to virus was also significantly higher following immunization. The results showed that, despite improved lymphocyte proliferation, fish oil impairs primary virus-specific T lymphocyte cytotoxicity. This impairment may explain the delayed virus clearance that we have previously reported in infected mice fed the fish oil diet. PMID:10632664

Fish oil feeding enhances lymphocyte proliferation but impairs virus-specific T lymphocyte cytotoxicity in mice following challenge with influenza virus.

PubMed

Byleveld, M; Pang, G T; Clancy, R L; Roberts, D C

2000-02-01

The effect of a fish oil diet on virus-specific cytotoxicity and lymphocyte proliferation was investigated. Mice were fed fish oil (17 g fish oil and 3 g sunflower/100 g) or beef tallow (17 g tallow and 3 g sunflower/100 g) diets for 14 days before intranasal challenge with influenza virus. At day 5 after infection, lung virus-specific T lymphocyte, but not macrophage or natural killer (NK) cell, cytotoxicity was significantly lower in mice fed fish oil, while bronchial lymph node cell proliferation to virus was significantly higher. In mice fed fish oil, spleen cell proliferation to virus was also significantly higher following immunization. The results showed that, despite improved lymphocyte proliferation, fish oil impairs primary virus-specific T lymphocyte cytotoxicity. This impairment may explain the delayed virus clearance that we have previously reported in infected mice fed the fish oil diet.

Effect of reduced exposure times on the cytotoxicity of resin luting cements cured by high-power led

PubMed Central

ERGUN, Gulfem; EGILMEZ, Ferhan; YILMAZ, Sukran

2011-01-01

Objective Applications of resin luting agents and high-power light-emitting diodes (LED) light-curing units (LCUs) have increased considerably over the last few years. However, it is not clear whether the effect of reduced exposure time on cytotoxicity of such products have adequate biocompatibility to meet clinical success. This study aimed at assessing the effect of reduced curing time of five resin luting cements (RLCs) polymerized by high-power LED curing unit on the viability of a cell of L-929 fibroblast cells. Material and Methods Disc-shaped samples were prepared in polytetrafluoroethylene moulds with cylindrical cavities. The samples were irradiated from the top through the ceramic discs and acetate strips using LED LCU for 20 s (50% of the manufacturer's recommended exposure time) and 40 s (100% exposure time). After curing, the samples were transferred into a culture medium for 24 h. The eluates were obtained and pipetted onto L-929 fibroblast cultures (3x104 per well) and incubated for evaluating after 24 h. Measurements were performed by dimethylthiazol diphenyltetrazolium assay. Statistical significance was determined by two-way ANOVA and two independent samples were compared by t-test. Results Results showed that eluates of most of the materials polymerized for 20 s (except Rely X Unicem and Illusion) reduced to a higher extent cell viability compared to samples of the same materials polymerized for 40 s. Illusion exhibited the least cytotoxicity for 20 s exposure time compared to the control (culture without samples) followed by Rely X Unicem and Rely X ARC (90.81%, 88.90%, and 83.11%, respectively). For Rely X ARC, Duolink and Lute-It 40 s exposure time was better (t=-1.262 p=0,276; t=-9.399 p=0.001; and t=-20.418 p<0.001, respectively). Conclusion The results of this study suggest that reduction of curing time significantly enhances the cytotoxicity of the studied resin cement materials, therefore compromising their clinical performance. PMID

Can immunostimulatory agents enhance the abscopal effect of radiotherapy?

PubMed

Levy, Antonin; Chargari, Cyrus; Marabelle, Aurelien; Perfettini, Jean-Luc; Magné, Nicolas; Deutsch, Eric

2016-07-01

Ionising radiation (IR) may harm cancer cells through a rare indirect out-of-field phenomenon described as the abscopal effect. Increasing evidence demonstrates that radiotherapy could be capable of generating tumour-specific immune responses. On the other hand, effects of IR also include inhibitory immune signals on the tumour microenvironment. Following these observations, and in the context of newly available immunostimulatory agents in metastatic cancers (anti-cytotoxic T lymphocyte-associated antigen 4 and programmed cell death protein-1 or -ligand 1 [PD1 or PDL-1]), there is a remarkable potential for synergistic combinations of IR with such agents that act through the reactivation of immune surveillance. Here, we present and discuss the pre-clinical and clinical rationale supporting the enhancement of the abscopal effect of IR on the blockade of immune checkpoints and discuss the evolving potential of immunoradiotherapy. Copyright © 2016 Elsevier Ltd. All rights reserved.

Design of New Antibacterial Enhancers Based on AcrB's Structure and the Evaluation of Their Antibacterial Enhancement Activity.

PubMed

Song, Yi; Qin, Rongxin; Pan, Xichun; Ouyang, Qin; Liu, Tianyu; Zhai, Zhaoxia; Chen, Yingchun; Li, Bin; Zhou, Hong

2016-11-18

Previously, artesunate (AS) and dihydroartemisinine 7 (DHA7) were found to have antibacterial enhancement activity against Escherichia coli via inhibition of the efflux pump AcrB. However, they were only effective against E. coli standard strains. This study aimed to develop effective antibacterial enhancers based on the previous work. Our results demonstrate that 86 new antibacterial enhancers were designed via 3D-SAR and molecular docking. Among them, DHA27 had the best antibacterial enhancement activity. It could potentiate the antibacterial effects of ampicillin against not only E. coli standard strain but also clinical strains, and of β-lactam antibiotics, not non-β-lactamantibiotics. DHA27 could increase the accumulation of daunomycin and nile red within E. coli ATCC 35218, but did not increase the bacterial membrane permeability. DHA27 reduced acrB 's mRNA expression of E. coli ATCC 35218 in a dose-dependent manner, and its antibacterial enhancement activity is related to the degree of acrB mRNA expression in E. coli clinical strains. The polypeptides from AcrB were obtained via molecular docking assay; the pre-incubated polypeptides could inhibit the activity of DHA27. Importantly, DHA27 had no cytotoxicity on cell proliferation. In conclusion, among newly designed antibacterial enhancers, DHA27 had favorable physical and pharmacological properties with no significant cytotoxicity at effective concentrations, and might serve as a potential efflux pump inhibitor in the future.

Cytotoxicity of Protein-Carbon Nanotubes on J774 Macrophages Is a Functionalization Grade-Dependent Effect

PubMed Central

Montes-Fonseca, Silvia Lorena; Sánchez-Ramírez, Blanca; Luna-Velasco, Antonia; Arzate-Quintana, Carlos; Silva-Cazares, Macrina Beatriz; González Horta, Carmen

2015-01-01

Carbon nanotubes (CNTs) are used as carriers in medicine due to their ability to be functionalized with chemical substances. However, cytotoxicity analysis is required prior to use for in vivo models. The aim of this study was to evaluate the cytotoxic effect of CNTs functionalized with a 46 kDa surface protein from Entamoeba histolytica (P46-CNTs) on J774A macrophages. With this purpose, CNTs were synthesized by spray pyrolysis and purified (P-CNTs) using sonication for 48 h. A 46 kDa protein, with a 4.6–5.4 pI range, was isolated from E. histolytica HM1:IMSS strain trophozoites using an OFFGEL system. The P-CNTs were functionalized with the purified 46 kDa protein, classified according to their degree of functionalization, and characterized by Raman and Infrared spectroscopy. In vitro cytotoxicity was evaluated by MTT, apoptosis, and morphological assays. The results demonstrated that P46-CNTs exhibited cytotoxicity dependent upon the functionalized grade. Contrary to what was expected, P46-CNTs with a high grade of functionalization were more toxic to J774 macrophages than P46-CNTs with a low grade of functionalization, than P-CNTs, and had a similar level of toxicity as UP-CNT. This suggests that the nature of the functionalized protein plays a key role in the cytotoxicity of these nanoparticles. PMID:26075262

Tribody [(HER2)2xCD16] Is More Effective Than Trastuzumab in Enhancing γδ T Cell and Natural Killer Cell Cytotoxicity Against HER2-Expressing Cancer Cells.

PubMed

Oberg, Hans H; Kellner, Christian; Gonnermann, Daniel; Sebens, Susanne; Bauerschlag, Dirk; Gramatzki, Martin; Kabelitz, Dieter; Peipp, Matthias; Wesch, Daniela

2018-01-01

An enhanced expression of human epidermal growth factor receptor 2 (HER2, ErbB2) often occurs in an advanced stage of breast, ovarian, gastric or esophageal cancer, and pancreatic ductal adenocarcinoma (PDAC). Commonly, HER2 expression is associated with poor clinical outcome or chemoresistance in ovarian and breast cancer patients. Treatment with humanized anti-HER2 monoclonal antibodies, such as trastuzumab or pertuzumab, has improved the outcome of patients with HER2-positive metastatic gastric or breast cancer, but not all patients benefit. In this study, the bispecific antibody [(HER2) 2 xCD16] in the tribody format was employed to re-direct CD16-expressing γδ T lymphocytes as well as natural killer (NK) cells to the tumor-associated cell surface antigen HER2 to enhance their cytotoxic anti-tumor activity. Tribody [(HER2) 2 xCD16] comprises two HER2-specific single chain fragment variable fused to a fragment antigen binding directed to the CD16 (FcγRIII) antigen expressed on γδ T cells and NK cells. Our results revealed the superiority of tribody [(HER2) 2 xCD16] compared to trastuzumab in triggering γδ T cell and NK cell-mediated lysis of HER2-expressing tumor cells, such as PDAC, breast cancer, and autologous primary ovarian tumors. The increased efficacy of [(HER2) 2 xCD16] can be explained by an enhanced degranulation of immune cells. Although CD16 expression was decreased on γδ T cells in several PDAC patients and the number of tumor-infiltrating NK cells and γδ T cells was impaired in ovarian cancer patients, [(HER2) 2 xCD16] selectively enhanced cytotoxicity of cells from these patients. Here, unique anti-tumor properties of tribody [(HER2) 2 xCD16] are identified which beyond addressing HER2 overexpressing solid tumors may allow to treat with similar immunoconstructs combined with the adoptive transfer of γδ T cells and NK cells refractory hematological malignancies. A major advantage of γδ T cells and NK cells in the transplant

Tribody [(HER2)2xCD16] Is More Effective Than Trastuzumab in Enhancing γδ T Cell and Natural Killer Cell Cytotoxicity Against HER2-Expressing Cancer Cells

PubMed Central

Oberg, Hans H.; Kellner, Christian; Gonnermann, Daniel; Sebens, Susanne; Bauerschlag, Dirk; Gramatzki, Martin; Kabelitz, Dieter; Peipp, Matthias; Wesch, Daniela

2018-01-01

An enhanced expression of human epidermal growth factor receptor 2 (HER2, ErbB2) often occurs in an advanced stage of breast, ovarian, gastric or esophageal cancer, and pancreatic ductal adenocarcinoma (PDAC). Commonly, HER2 expression is associated with poor clinical outcome or chemoresistance in ovarian and breast cancer patients. Treatment with humanized anti-HER2 monoclonal antibodies, such as trastuzumab or pertuzumab, has improved the outcome of patients with HER2-positive metastatic gastric or breast cancer, but not all patients benefit. In this study, the bispecific antibody [(HER2)2xCD16] in the tribody format was employed to re-direct CD16-expressing γδ T lymphocytes as well as natural killer (NK) cells to the tumor-associated cell surface antigen HER2 to enhance their cytotoxic anti-tumor activity. Tribody [(HER2)2xCD16] comprises two HER2-specific single chain fragment variable fused to a fragment antigen binding directed to the CD16 (FcγRIII) antigen expressed on γδ T cells and NK cells. Our results revealed the superiority of tribody [(HER2)2xCD16] compared to trastuzumab in triggering γδ T cell and NK cell-mediated lysis of HER2-expressing tumor cells, such as PDAC, breast cancer, and autologous primary ovarian tumors. The increased efficacy of [(HER2)2xCD16] can be explained by an enhanced degranulation of immune cells. Although CD16 expression was decreased on γδ T cells in several PDAC patients and the number of tumor-infiltrating NK cells and γδ T cells was impaired in ovarian cancer patients, [(HER2)2xCD16] selectively enhanced cytotoxicity of cells from these patients. Here, unique anti-tumor properties of tribody [(HER2)2xCD16] are identified which beyond addressing HER2 overexpressing solid tumors may allow to treat with similar immunoconstructs combined with the adoptive transfer of γδ T cells and NK cells refractory hematological malignancies. A major advantage of γδ T cells and NK cells in the transplant situation of

Pharmacologic modification of the cytotoxic effects of cadmium in LLC-PK sub 1 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Battaglia, D.R.; Kahan, B.S.; Niewenhuis, R.J.

1989-02-09

Recent results from our laboratories have shown that exposure to cadmium causes LLC-PK{sub 1} cells to shrink, detach and assume a spherical shape. The purpose of the present studies was to determine whether various pharmacologic agents can reduce or prevent these cytotoxic effects of Cd{sup 2+}. Confluent monolayers of LLC-PK{sub 1} cells were incubated with the drugs of interest (50 microM final concentration) for 2 hours. CadCl{sub 2} (final concentration = 75 microM) was then added and the cells were incubated for another 20 hours. Morphologic changes were assessed qualitatively by viewing the cells with a phase contrast microscope. Themore » extent of Cd{sup 2+}-induced cellular damage was also quantified by staining the cells that remained on the growing surface with methylene blue, solubilizing the stained cells, and determining the absorbance at 660 nm. The results showed that several drugs, particularly the calmodulin antagonists trifluoperazine chlorpromazine, and the calcium channel blocker verapamil, significant reduced the severity of Cd{sup 2+}-induced cytotoxicity. By contrast, a variety of other agents, such as chlorpromazine sulfoxide, trifluoperazine sulfoxide, phenytoin and zinc, had no such protective effect. These findings indicate that Ca{sup 2+} antagonists can attenuate the cytotoxic effects of Cd{sup 2+} and that Cd{sup 2+} may produce some of its effects by activating Ca{sup 2+} -dependent systems.« less

Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset.

PubMed

Gualde, N; Goodwin, J S

1984-04-01

Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less [3H]thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced [3H]thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), and OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.

Differential role of thiopurine methyltransferase in the cytotoxic effects of 6-mercaptopurine and 6-thioguanine on human leukemia cells.

PubMed

Karim, Hazhar; Ghalali, Aram; Lafolie, Pierre; Vitols, Sigurd; Fotoohi, Alan K

2013-07-26

The thiopurine antimetabolites, 6-mercaptopurine (6-MP) and 6-thioguanine (6-TG) are inactive pro-drugs that require intracellular metabolism for activation to cytotoxic metabolites. Thiopurine methyltransferase (TPMT) is one of the most important enzymes in this process metabolizing both 6-MP and 6-TG to different methylated metabolites including methylthioinosine monophosphate (meTIMP) and methylthioguanosine monophosphate (meTGMP), respectively, with different suggested pharmacological and cytotoxic properties. While meTIMP is a potent inhibitor of de novo purine synthesis (DNPS) and significantly contributes to the cytotoxic effects of 6-MP, meTGMP, does not add much to the effects of 6-TG, and the cytotoxicity of 6-TG seems to be more dependent on incorporation of thioguanine nucleotides (TGNs) into DNA rather than inhibition of DNPS. In order to investigate the role of TPMT in metabolism and thus, cytotoxic effects of 6-MP and 6-TG, we knocked down the expression of the gene encoding the TPMT enzyme using specifically designed small interference RNA (siRNA) in human MOLT4 leukemia cells. The knock-down was confirmed at RNA, protein, and enzyme function levels. Apoptosis was determined using annexin V and propidium iodide staining and FACS analysis. The results showed a 34% increase in sensitivity of MOLT4 cells to 1μM 6-TG after treatment with TPMT-targeting siRNA, as compared to cells transfected with non-targeting siRNA, while the sensitivity of the cells toward 6-MP was not affected significantly by down-regulation of the TPMT gene. This differential contribution of the enzyme TPMT to the cytotoxicity of the two thiopurines is probably due to its role in formation of the meTIMP, the cytotoxic methylated metabolite of 6-MP, while in case of 6-TG methylation by TPMT substantially deactivates the drug. Copyright © 2013 Elsevier Inc. All rights reserved.

Evaluation of cytotoxicity of surfactants used in self-micro emulsifying drug delivery systems and their effects on paracellular transport in Caco-2 cell monolayer.

PubMed

Ujhelyi, Zoltán; Fenyvesi, Ferenc; Váradi, Judit; Fehér, Pálma; Kiss, Tímea; Veszelka, Szilvia; Deli, Mária; Vecsernyés, Miklós; Bácskay, Ildikó

2012-10-09

The objective of this study was to examine the cellular effects of the members of two non-ionic amphiphilic tenside groups and their mixtures on human Caco-2 cell monolayers as dependent upon their chemical structures and physicochemical properties. The first group of polyethylene glycol esters is represented by Polysorbates and Labrasol alone and in blends, while the members of the second group. Capryol 90, Capryol PGMC, Lauroglycol 90 and Lauroglycol FCC were used as propylene glycol esters. They are increasingly used in SMEDDS as recent tensides or co-tensides to increase hydrophobic bioavailability of a drug. Critical micelle concentration was measured by determination of surface tension. CMC refers to the ability of solubilization of surfactants. Cytotoxicity tests were performed on Caco-2 cell monolayers by MTT and LDH methods. Paracellular permeability as a marker of the integrity of cell monolayers, was examined with Lucifer yellow assays combined with TransEpithelial Electrical Resistance (TEER) measurements. The effect of these surfactants on tight junctions as evidence for paracellular pathway was also characterized. The results of cytotoxicity assays were in agreement, and showed significant differences among the cytotoxic properties of surfactants in a concentration-dependent manner. Polysorbates 20, 60, 80 are the most toxic compounds. In the case of Labrasol, the degree of esterification and lack of sorbit component decreased cytotoxicity. If the hydrophyl head was changed from polyethylene glycol to propylene glycol the main determined factor of cytotoxicity was the monoester content and the length of carbon chain. In our CMC experiments, we found that only Labrasol showed expressed cytotoxicity above the CMC. It refers to good ability of micelle solubilization of Labrasol. In our paracellular transport experiments each of polyethylene glycol surfactants (Polysorbates and Labrasol) altered TEER values, but propylene glycol esters did not modify the

Multiwalled carbon nanotubes effect on the bioavailability of artemisinin and its cytotoxity to cancerous cells

NASA Astrophysics Data System (ADS)

Rezaei, Behzad; Majidi, Najmeh; Noori, Shokoofe; Hassan, Zuhair M.

2011-12-01

Artemisinin regarded as one of the most promising anticancer drugs can bind to DNA with a binding constant of 1.04 × 104 M-1. The electrochemical experiments indicated that for longer incubation time periods, the reduction peak current of artemisinin on carbon nanotube modified electrode increases. Therefore, the uptake of drug molecules from a solution into CNTs will be achieved automatically by adsorption of 88.7% of artemisinin onto carbon nanotubes surface without alteration in drug properties. Hence, capability of carbon nanotubes to have synergistic effect on the bioavailability of artemisinin was investigated. Experimental tests on K562 cancer cell lines growth by MTT assay proved that multi-walled carbon nanotubes can enhance the cytotoxity of artemisinin to the targeted cancer cells with unprecedented accuracy and efficiency. The IC50 values were 65 and 35 μM for artemisinin and artemisinin loaded on multi-walled carbon nanotubes, respectively; demonstrating that artemisinin loaded on multi-walled carbon nanotubes is more effective in inhibition of cancer cell lines growth.

The Genotoxic and Cytotoxic Effects of Bisphenol-A (BPA) in MCF-7 Cell Line and Amniocytes.

PubMed

Aghajanpour-Mir, Seyed Mohsen; Zabihi, Ebrahim; Akhavan-Niaki, Haleh; Keyhani, Elahe; Bagherizadeh, Iman; Biglari, Sajjad; Behjati, Farkhondeh

2016-01-01

Bisphenol-A (BPA) is an industrial xenoestrogen used widely in our living environment. Recently, several studies suggested that BPA has destructive effects on DNA and chromosomes in normal body cells via estrogen receptors (ER). Therefore, BPA could be considered as an important mediator in many diseases such as cancer. However, there are still many controversial issues which need clarification. In this study, we investigated the BPA-induced chromosomal damages in MCF-7 cell line, ER-positive and negative amniocyte cells. Cytotoxicity and genotoxicity effects of BPA were also compared between these three cell groups. Expression of estrogen receptors was determined using immunocytochemistry technique. The cell cytotoxicity of BPA was measured by MTT assay. Classic cytogenetic technique was carried out for the investigation of chromosome damage. BPA, in addition to cytotoxicity, had remarkable genotoxicity at concentrations close to the traceable levels in tissues or biological fluids. Although some differences were observed in the amount of damages between ER-positive and negative fetal cells, interestingly, these differences were not significant. The present study showed that BPA could lead to chromosomal aberrations in both ER-dependent and independent pathways at some concentrations or in cell types yet not reported. Also, BPA could probably be considered as a facilitator for some predisposed cells to be cancerous by raising the chromosome instability levels. Finally, estrogen receptor seems to have a different role in cytotoxicity and genotoxicity effects.

CYTOTOXIC EFFECTS OF SOME MINERAL DUSTS ON SYRIAN HAMSTER PERITONEAL MACROPHAGES

PubMed Central

Bey, Elke; Harington, J. S.

1971-01-01

Hamster peritoneal macrophages were grown in cell culture and their response to various conditions was examined. The cultures responded favorably to high concentrations of serum and to medium which had been preconditioned by contact with tumor cells. After 2–3 days of adaptation, they entered into a period of stability which lasted from the 4th to the 9th day. Macrophage cultures in this stable phase were treated with various samples of mineral dusts and their response determined by counting the number of viable macrophages/cm2 at intervals over a period of 72 hr. Crystalline silica Snowit was found to be nontoxic. Amorphous silica Fransil caused a characteristic cytotoxic effect and a rapid decline in cell population at doses less than 150 µg/5 x 105 cells. Of the three different kinds of asbestos used, chrysotile was toxic and amosite and crocidolite nontoxic at equivalent concentrations. A comparison of two preparations of chrysotile which differed in surface area showed that weight rather than surface area determines toxicity. Pretreatment of chrysotile with tryptose phosphate broth under drastic conditions accelerated but did not increase the final intensity of the cytotoxic effect. PMID:4101804

Microbial-assisted synthesis and evaluation the cytotoxic effect of tellurium nanorods.

PubMed

Forootanfar, Hamid; Amirpour-Rostami, Sahar; Jafari, Mandana; Forootanfar, Amir; Yousefizadeh, Zahra; Shakibaie, Mojtaba

2015-04-01

The present study was designed to isolate bacterial strain capable of tellurium nanorods' (Te NRs) production followed by purification and evaluation of the cytotoxic effect of Te NRs. Among 25 environmental samples collected for screening of Te NR-producer bacterial strains one bacterial colony (isolated from hot spring and identified as Pseudomonas pseudoalcaligenes strain Te) was selected and applied for biosynthesis of Te NRs. Thereafter, an organic-aqueous partitioning system was applied for the purification of the biogenic Te NRs and the purified Te NRs were characterized using transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction spectroscopy (XRD), UV-visible spectroscopy, and Fourier transform infrared spectroscopy (FTIR) techniques. The cytotoxic effect of biologically synthesized Te NRs and potassium tellurite on four cell lines of MCF-7, HT1080, HepG2 and A549 was then determined using the MTT assay method. The obtained results revealed lower toxicity for the rod-shaped biogenic tellurium nanostructures (~22nm diameter by 185nm length) compared to K2TeO3. Copyright © 2014. Published by Elsevier B.V.

Comparative evaluation of cytotoxicity of a glucosamine-TBA conjugate and a chitosan-TBA conjugate.

PubMed

Guggi, Davide; Langoth, Nina; Hoffer, Martin H; Wirth, Michael; Bernkop-Schnürch, Andreas

2004-07-08

D-glucosamine and chitosan were modified by the immobilization of thiol groups utilizing 2-iminothiolane. The toxicity profile of the resulting D-glucosamine-TBA (4-thiobutylamidine) conjugate, of chitosan-TBA conjugate and of the corresponding unmodified controls was evaluated in vitro. On the one hand, the cell membrane damaging effect of 0.025% solutions of the test compounds was investigated via red blood cell lysis test. On the other hand, the cytotoxity of 0.025, 0.25 and 0.5% solutions of the test compounds was evaluated on L-929 mouse fibroblast cells utilizing two different bioassays: the MTT assay (3-[4,5-dimethylthiazol-2yl]-2,5-diphenyltetrazolium bromide), which assess the mitochondrial metabolic activity of the cells, and the BrdU-based enzyme-linked immunosorbent assay, which measures the incorporation in the DNA of 5-bromo-2'-deoxyuridine and consequently the cell proliferation. Results of the red blood cell lysis test showed that both thiolated compounds displayed a lower membrane damaging effect causing a significantly lower haemoglobine release than the unmodified compounds. Data obtained by the MTT assay and the BrdU assay revealed a concentration dependent relative cytotoxicity for all tested compounds. The covalent linkage of the TBA-substructure to D-glucosamine did not cause a significant increase in cytotoxicity, whereas at higher concentrations a slightly enhanced cytotoxic effect was caused by the derivatisation of chitosan. In conclusion, the -TBA derivatives show a comparable toxicity profile to the corresponding unmodified compounds, which should not compromise their future use as save pharmaceutical excipients.

A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines.

PubMed

Solarte, Víctor A; Rosas, Jaiver E; Rivera, Zuly J; Arango-Rodríguez, Martha L; García, Javier E; Vernot, Jean-Paul

2015-01-01

Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC) cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20-25)4, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90%) in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC.

Cytotoxicity and mycotoxin production of shellfish-derived Penicillium spp., a risk for shellfish consumers.

PubMed

Geiger, M; Guitton, Y; Vansteelandt, M; Kerzaon, I; Blanchet, E; Robiou du Pont, T; Frisvad, J C; Hess, P; Pouchus, Y F; Grovel, O

2013-11-01

In order to assess the putative toxigenic risk associated with the presence of fungal strains in shellfish-farming areas, Penicillium strains were isolated from bivalve molluscs and from the surrounding environment, and the influence of the sample origin on the cytotoxicity of the extracts was evaluated. Extracts obtained from shellfish-derived Penicillia exhibited higher cytotoxicity than the others. Ten of these strains were grown on various media including a medium based on mussel extract (Mytilus edulis), mussel flesh-based medium (MES), to study the influence of the mussel flesh on the production of cytotoxic compounds. The MES host-derived medium was created substituting the yeast extract of YES medium by an aqueous extract of mussel tissues, with other constituent identical to YES medium. When shellfish-derived strains of fungi were grown on MES medium, extracts were found to be more cytotoxic than on the YES medium for some of the strains. HPLC-UV/DAD-MS/MS dereplication of extracts from Penicillium marinum and P. restrictum strains grown on MES medium showed the enhancement of the production of some cytotoxic compounds. The mycotoxin patulin was detected in some P. antarcticum extracts, and its presence seemed to be related to their cytotoxicity. Thus, the enhancement of the toxicity of extracts obtained from shellfish-derived Penicillium strains grown on a host-derived medium, and the production of metabolites such as patulin suggests that a survey of mycotoxins in edible shellfish should be considered. © 2013 The Society for Applied Microbiology.

Before In Vivo Imaging: Evaluation of Fluorescent Probes Using Fluorescence Microscopy, Multiplate Reader, and Cytotoxicity Assays.

PubMed

Zhang, Shaojuan

2016-01-01

Fluorescent probes are widely utilized for noninvasive fluorescence imaging. Continuing efforts have been made in developing novel fluorescent probes with improved fluorescence quantum yield, enhanced target-specificity, and lower cytotoxicity. Before such probes are administrated into a living system, it is essential to evaluate the subcellular uptake, targeting specificity, and cytotoxicity in vitro. In this chapter, we briefly outline common methods used to evaluate fluorescent probes using fluorescence microscopy, multiplate reader, and cytotoxicity assay.

Paclitaxel Enhances Carboplatin-DNA Adduct Formation and Cytotoxicity

DOE PAGES

Jiang, Shuai; Pan, Amy W.; Lin, Tzu-yin; ...

2015-11-06

This rapid report focuses on the pharmacodynamic mechanism of the carboplatin/paclitaxel combination and correlates it with its cytotoxicity. Consistent with the synergistic to additive antitumor activity (the combination index ranging from 0.53 to 0.94), cells exposed to this combination had significantly increased carboplatin-DNA adduct formation when compared to that of carboplatin alone (450 ± 30 versus 320 ± 120 adducts per 10 8 nucleotides at 2 h, p = 0.004). Removal of paclitaxel increased the repair of carboplatin-DNA adducts: 39.4 versus 33.1 adducts per 10 8 nucleotides per hour in carboplatin alone (p = 0.021). In conclusion, this rapid reportmore » provides the first pharmacodynamics data to support the use of carboplatin/paclitaxel combination in the clinic.« less

Analysis of cytotoxic effects of silver nanoclusters on human peripheral blood mononuclear cells 'in vitro'.

PubMed

Orta-García, Sandra Teresa; Plascencia-Villa, Germán; Ochoa-Martínez, Angeles Catalina; Ruiz-Vera, Tania; Pérez-Vázquez, Francisco Javier; Velázquez-Salazar, J Jesús; Yacamán, Miguel José; Navarro-Contreras, Hugo Ricardo; Pérez-Maldonado, Iván N

2015-10-01

The antimicrobial properties of silver nanoparticles (AgNPs) have made these particles one of the most used nanomaterials in consumer products. Therefore, an understanding of the interactions (unwanted toxicity) between nanoparticles and human cells is of significant interest. The aim of this study was to assess the in vitro cytotoxicity effects of silver nanoclusters (AgNC, < 2 nm diameter) on peripheral blood mononuclear cells (PBMC). Using flow cytometry and comet assay methods, we demonstrate that exposure of PBMC to AgNC induced intracellular reactive oxygen species (ROS) generation, DNA damage and apoptosis at 3, 6 and 12 h, with a dose-dependent response (0.1, 1, 3, 5 and 30 µg ml(-1)). Advanced electron microscopy imaging of complete and ultrathin-sections of PBMC confirmed the cytotoxic effects and cell damage caused by AgNC. The present study showed that AgNC produced without coating agents induced significant cytotoxic effects on PBMC owing to their high aspect ratio and active surface area, even at much lower concentrations (<1 µg ml(-1)) than those applied in previous studies, resembling what would occur under real exposure conditions to nanosilver-functionalized consumer products. Copyright © 2015 John Wiley & Sons, Ltd.

Photo-inducible cytotoxic and clastogenic activities of 3,6-di-substituted acridines obtained by acylation of proflavine.

PubMed

Benchabane, Yohann; Di Giorgio, Carole; Boyer, Gérard; Sabatier, Anne-Sophie; Allegro, Diane; Peyrot, Vincent; De Méo, Michel

2009-06-01

The cytotoxicity and photo-enhanced cytotoxicity of a series of 18 3,6-di-substituted acridines were evaluated on both tumour CHO cells and human normal keratinocytes, and compared to their corresponding clastogenicity as assessed by the micronucleus assay. Compounds 2f tert-butyl N-[(6-tert-butoxycarbonylamino)acridin-3-yl]carbamate and 2d N-[6-(pivalamino)acridin-3-yl]pivalamide displayed a specific cytotoxicity on CHO cells. These results suggested that the two derivatives could be considered as interesting candidates for anticancer chemotherapy and hypothesized that the presence of 1,1-dimethylethyl substituents was responsible for a strong nonclastogenic cytotoxicity. Compounds 2b and 2c, on the contrary, displayed a strong clastogenicity. They indicated that the presence of nonbranched aliphatic chains on positions 3 and 6 of the acridine rings tended to induce a significant clastogenic effect. Finally, they established that most of the acridine compounds could be photo-activated by UVA-visible rays and focussed on the significant role of light irradiation on their biological properties.

Antiproliferative/cytotoxic effects of molecular iodine, povidone-iodine and Lugol's solution in different human carcinoma cell lines.

PubMed

Rösner, Harald; Möller, Wolfgang; Groebner, Sabine; Torremante, Pompilio

2016-09-01

Clinical trials have revealed that molecular iodine (I 2 ) has beneficial effects in fibrocystic breast disease and in cyclic mastalgia. Likewise, povidone-iodine (PVP-I), which is widely used in clinical practice as an antiseptic agent following tumour surgery, has been demonstrated to have cytotoxic effects on colon cancer and ascites tumour cells. Our previous study indicated that the growth of breast cancer and seven other human malignant cell lines was variably diminished by I 2 and iodolactones. With the intention of developing an iodine-based anticancer therapy, the present investigations extended these studies by comparing the cytotoxic capacities of I 2 , potassium iodide (KJ), PVP-I and Lugol's solution on various human carcinoma cell lines. Upon staining the cell nuclei with Hoechst 33342, the cell densities were determined microscopically. While KJ alone did not affect cell proliferation, it enhanced the antiproliferative activity of I 2 . In addition, PVP-I significantly inhibited the proliferation of human MCF-7 breast carcinoma, IPC melanoma, and A549 and H1299 lung carcinoma cells in a concentration corresponding to 20 µM I 2 . Likewise, Lugol's solution in concentrations corresponding to 20-80 µM I 2 were observed to reduce the growth of MCF-7 cells. Experiments with fresh human blood samples revealed that the antiproliferative activity of PVP-I and I 2 is preserved in blood plasma to a high degree. These findings suggest that PVP-I, Lugol's solution, and a combination of iodide and I 2 may be potent agents for use in the development of antitumour strategies.

Antiproliferative/cytotoxic effects of molecular iodine, povidone-iodine and Lugol's solution in different human carcinoma cell lines

PubMed Central

Rösner, Harald; Möller, Wolfgang; Groebner, Sabine; Torremante, Pompilio

2016-01-01

Clinical trials have revealed that molecular iodine (I2) has beneficial effects in fibrocystic breast disease and in cyclic mastalgia. Likewise, povidone-iodine (PVP-I), which is widely used in clinical practice as an antiseptic agent following tumour surgery, has been demonstrated to have cytotoxic effects on colon cancer and ascites tumour cells. Our previous study indicated that the growth of breast cancer and seven other human malignant cell lines was variably diminished by I2 and iodolactones. With the intention of developing an iodine-based anticancer therapy, the present investigations extended these studies by comparing the cytotoxic capacities of I2, potassium iodide (KJ), PVP-I and Lugol's solution on various human carcinoma cell lines. Upon staining the cell nuclei with Hoechst 33342, the cell densities were determined microscopically. While KJ alone did not affect cell proliferation, it enhanced the antiproliferative activity of I2. In addition, PVP-I significantly inhibited the proliferation of human MCF-7 breast carcinoma, IPC melanoma, and A549 and H1299 lung carcinoma cells in a concentration corresponding to 20 µM I2. Likewise, Lugol's solution in concentrations corresponding to 20–80 µM I2 were observed to reduce the growth of MCF-7 cells. Experiments with fresh human blood samples revealed that the antiproliferative activity of PVP-I and I2 is preserved in blood plasma to a high degree. These findings suggest that PVP-I, Lugol's solution, and a combination of iodide and I2 may be potent agents for use in the development of antitumour strategies. PMID:27602156

Cytotoxic effect induced by retinoic acid loaded into galactosyl-sphingosine containing liposomes on human hepatoma cell lines.

PubMed

Díaz, Cecilia; Vargas, Ernesto; Gätjens-Boniche, Omar

2006-11-15

Two retinoids, ATRA and 13cisRA, were incorporated into liposomes of different composition and charge and added to two hepatoma cell lines with different degree of transformation to measure cytotoxicity by MTT assay. Retinoid-free cationic liposomes were more toxic than the other kinds (anionic and made only of PC) but were also the best delivery system for retinoic acid to induce specific cytotoxic effects on these tumor hepatoma cell lines. Galactosyl-sphingosine containing cationic liposomes increased the cytotoxic effect induced by ATRA on Hep3B cells when compared to glucosyl-sphingosine cationic liposomes, but did not improve the effect induced by free retinoid or ATRA loaded into liposomes without glycolipids. This suggests that in this cell line, ATRA is being incorporated by a mechanism mediated by the asialoglycoprotein receptor, but at the same time, non-specific sugar-independent capture is also taking place as well as free diffusion of ATRA directly through the membrane. Galactose-specific effect was not observed in HepG2 cells treated with ATRA or both cell lines treated with 13cisRA. In fact, treatment of HepG2 cells with retinoids entrapped into liposomes likely induces proliferation instead of cytotoxicity, a result that interferes with the measurement of cell death by MTT. Compared to the specific effect of ATRA entrapped into cationic liposomes, vesicles made only by PC, did not mediate a specific mechanism, since differences between ATRA in galactosyl- and glucosyl-shpingosine PC-liposomes were not statistically significant. The specific mechanism was not present in the myoblastic cell line C2C12, where ATRA incorporated into galactosyl- and glucosyl-sphingosine containing cationic and PC-liposomes, was able to induce cytotoxicity at the same extent. Micelles containing ATRA and galactosyl-sphingosine had a significantly more toxic effect than the retinoid administered together with glucosyl-sphingosine, in Hep3B cells. Also, micelles containing

Lenalidomide Synergistically Enhances the Effect of Dendritic Cell Vaccination in a Model of Murine Multiple Myeloma.

PubMed

Nguyen-Pham, Thanh-Nhan; Jung, Sung-Hoon; Vo, Manh-Cuong; Thanh-Tran, Huong-Thi; Lee, Youn-Kyung; Lee, Hyun-Ju; Choi, Nu-Ri; Hoang, My-Dung; Kim, Hyeoung-Joon; Lee, Je-Jung

2015-10-01

We investigated the efficacy of lenalidomide (LEN) in combination with dendritic cell (DC) vaccination in the MOPC-315 murine myeloma model. After tumor growth, LEN was injected intraperitoneally for 4 consecutive days in combination with DC vaccination. The combination of LEN and vaccination efficiently inhibited tumor growth compared with the single agents alone. A cytotoxic assay revealed that the anticancer effects of DC vaccination plus LEN involved not only generation of antigen-specific cytotoxic T lymphocytes but also NK cells. Vaccinated mice had reduced numbers of suppressor cells, including both myeloid-derived suppressor cells and regulatory T cells, in the spleen. The proportions of CD4+ and CD8+ T cells increased in the spleen, and a Th1 cytokine (interferon-γ) rather than a Th2 cytokine (interleukin-10) was synthesized in response to tumor antigens. LEN enhanced the innate immune response by modulating NK cell numbers and function. In addition, LEN reduced the production levels of angiogenesis-inducing factors in tumor-bearing mice. Together, these results suggest that a combination of LEN and DC vaccination may synergistically enhance anticancer immunity in the murine myeloma model, by inhibiting immunosuppressor cells and stimulating effector cells, as well as effectively polarizing the Th1/Th2 balance in favor of a Th1-specific immune response.

Singlet Oxygen Scavenging Activity and Cytotoxicity of Essential Oils from Rutaceae

PubMed Central

Ao, Yoko; Satoh, Kazue; Shibano, Katsushige; Kawahito, Yukari; Shioda, Seiji

2008-01-01

Since we have been exposed to excessive amounts of stressors, aromatherapy for the relaxation has recently become very popular recently. However, there is a problem which responds to light with the essential oil used by aromatherapy. It is generally believed that singlet oxygen is implicated in the pathogenesis of various diseases such as light-induced skin disorders and inflammatory responses. Here we studied whether essential oils can effectively scavenge singlet oxygen upon irradiation, using the electron spin resonance (ESR) method. Green light was used to irradiate twelve essential oils from rutaceae. Among these twelve essential oils, eight were prepared by the expression (or the compression) method (referred to as E oil), and four samples were prepared by the steam distillation method (referred to as SD oil). Five E oils enhanced singlet oxygen production. As these essential oils may be phototoxic, it should be used for their use whit light. Two E oils and three SD oils showed singlet oxygen scavenging activity. These results may suggest that the antioxidant activity of essential oils are judged from their radical scavenging activity. Essential oils, which enhance the singlet oxygen production and show higher cytotoxicity, may contain much of limonene. These results suggest that limonene is involved not only in the enhancement of singlet oxygen production but also in the expression of cytotoxic activity, and that attention has to be necessary for use of blended essential oils. PMID:18648659

Enhancement in in vitro anti-angiogenesis activity and cytotoxicity in lung cancer cell by pectin-PVP based curcumin particulates.

PubMed

Gaikwad, Dinanath; Shewale, Rajnita; Patil, Vinit; Mali, Dipak; Gaikwad, Uday; Jadhav, Namdeo

2017-11-01

The aim of this work was to prepare pectin-poly (vinyl pyrrolidone) [PVP] based curcumin particulates to enhance the anticancer potential of curcumin, solubility and allow its localized controlled release. Pectin-PVP based curcumin particulates (PECTIN-PVP CUR) were prepared by spray drying technique in different ratios and were evaluated for surface morphology, micromeritics, flowability, particle size, drug content, in vitro dissolution, inhalable fraction, anti-angiogenesis/angiolysis and cytotoxicity. Results of micromeritic properties, Carr's index, Hausner's ratio and angle of repose were satisfactory. The batch CP3 was considered as optimum, due to excellent flowability, acceptable aggregation and enhanced solubility. The particle size and size distribution data of selected batch CP3 showed 90% of curcumin particulates having size less than 2.74μm, which may deposit to lungs. Twin Impinger studies showed that 29% of respirable fraction was generated, which could be directly delivered to lungs. The in vitro dissolution data showed many fold increase in dissolution rate. Angiolytic activity and MTT assay of PECTIN-PVP CUR have demonstrated enhancement in the anti-tumor potential, compared to curcumin alone. Altogether, PECTIN-PVP CUR were found suitable for local delivery and enhance its anticancer potential of curcumin. Copyright © 2017 Elsevier B.V. All rights reserved.

Cytotoxic effect of menadione and sodium orthovanadate in combination on human glioma cells.

PubMed

Delwar, Zahid M; Avramidis, Dimitrios; Follin, Elna; Hua, Yan; Siden, Åke; Cruz, Mabel; Paulsson, Kajsa M; Yakisich, Juan Sebastian

2012-08-01

Gliomas are the most common primary brain tumor, and their treatment is still a challenge. Here, we evaluated the antiproliferative effect of a novel combination of two potent oxidative stress enhancers: menadione (M) and sodium orthovanadate (SO). We observed both short-term and prolonged growth inhibitory effects of M or SO alone as well as in combination (M:SO) on DBTRG.05MG human glioma cells. A stronger antiproliferative effect was observed in the short-term proliferation assay with the M:SO combination compared to either investigated agent alone. In the long-term proliferation assay, a 10-day exposure to M:SO at concentrations of 10 μM:17.5 μM or 17.5 μM:10 μM was enough to kill 100% of the cells; no cell regrowth was observed after re-incubation in drug-free media. When used in combination, the single concentration of M and SO could be decreased by 2.5- to 5-fold of those used for each experimental drug alone and still obtain a similar antiproliferative effect. The underlying molecular mechanism was investigated by co-incubating M:SO with dithiothreitol (DTT) and genistein. Both substances partially neutralized the effects of the M:SO combination, showing additive effects. This observation suggests a role of oxidative stress and tyrosine kinase stimulation in the M:SO cytotoxic effect. Our results indicate that M:SO combination is an attractive alternative for glioma treatment that encourages further study. The neutralizing effects of genistein and DTT reveal a possibility for their use in the minimization of potential M:SO systemic toxicity.

Cytotoxic effects of resin-modified orthodontic band adhesives. Are they safe?

PubMed

Malkoc, Siddik; Corekci, Bayram; Botsali, Hayriye Esra; Yalçin, Muhammet; Sengun, Abdülkadir

2010-09-01

To evaluate the cytotoxic effects of three different resin-modified orthodontic band adhesives. Three resin-modified orthodontic band adhesives (Bisco Ortho Band Paste LC, Multi-Cure Glass Ionomer Band Cement, and Transbond Plus Light Cure Band Adhesive) were prepared and the samples were extracted in 3 mL of Basal Medium Eagle with 10% newborn calf serum for 24 hours. The L929 cells were plated (25,000 cells/mL) in wells of 96-well dishes and maintained in a humidified incubator for 24 hours at 37 degrees C, 5% CO(2), and 95% air. After 24-hour incubation of the cells, the incubation medium was replaced by the immersed medium in which the samples were stored. Then L929 cells were incubated in contact with eluates for 24 hours. The cell mitochondrial activity was evaluated by the methyltetrazolium test. Twelve wells were used for each specimen, and methyltetrazolium tests were applied two times. The data were statistically analyzed using one-way analysis of variance and Tukey Honestly Significantly Different tests. Results with L929 fibroblasts demonstrated that all freshly prepared resin-modified orthodontic band adhesive materials reduced vital cell numbers (P > .05), in comparison to the control group. Our data demonstrate that all materials showed significant cytotoxicity compared to the control group. The results indicate that all materials showed significant cytotoxicity compared to the control group, and further studies using different test methods are needed for all resin-modified orthodontic band adhesives.

Potentiation by Tumor Necrosis Factor of Mitoxantrone Cytotoxicity to Human Ovarian Cancer Cell Lines

PubMed Central

Parodi, Silvio; Billi, Giovanna; Oliva, Cristina; Venturing, Marco; Noviello, Elvira; Conte, PierFranco

1992-01-01

The cytotoxic activity of human recombinant tumor necrosis factor (rHuTNF) (from 0.01 to 10000 U/ml) was assayed on six human ovarian cancer cell lines and one human cervical carcinoma cell line using a crystal violet assay. rHuTNF was cytotoxic to four cell lines (A2780, A2774, SW626, PAD, while 3 cell lines (IGROV1, SKOV3, Mel80) were marginally sensitive to its activity. However, under the same experimental conditions rHuTNF markedly enhanced the cytotoxicity of mitoxantrone, a chemotherapeutic drug targeted at DNA topoisomerase II, in six cell lines. The potentiation of mitoxantrone cytotoxicity was not caused by increased drug accumulation after rHuTNF treatment. No significant increase in cytotoxicity to Me180 cell line was seen when rHuTNF was added to mitoxantrone. PMID:1517145

Anti-Fas Antibody Conjugated Nanoparticles Enhancing the Antitumor Effect of Camptothecin by Activating the Fas-FasL Apoptotic Pathway.

PubMed

Yu, Hongliang; He, Jian; Lu, Qian; Huo, Da; Yuan, Shanmei; Zhou, Zhengyang; Xu, Peipei; Hu, Yong

2016-11-09

Emerging evidence suggest that the introduction of Fas ligand (FasL) can enhance the Fas-dependent apoptosis and induce durable immune responses against tumor. However, selective triggering of apoptosis in tumor cells while sparing normal cells remains a great challenge for the application of FasL-based therapeutic strategies. Herein, smart nanoparticles (NPs) with a sandwich structure were fabricated. These NPs consist of a matrix metalloproteinase (MMP) cleavable PEG outer layer, an anti-Fas antibody middle layer, and a camptothecin (CPT)-loaded inner core. They could accumulate at a tumor site by the enhanced permeability and retention (EPR) effect. The removable PEG layer protects the cytotoxic anti-Fas antibody from premature contact with normal tissues, thus avoiding the unexpected lethal side effect before they reach the tumor site. Due to the high level of MMP expressed by tumor cells inside the tumor tissue, these NPs would shed their PEG layers, resulting in the exposure of anti-Fas antibody to bind the Fas receptor and triggering the apoptosis of tumor cells. Results of Western blot confirmed that these NPs could mimic the function of activated cytotoxic lymphocyte (CTL) to activate the Fas-FasL apoptosis pathway of tumor cells. With the aid of CPT payload, these anti-Fas antibody conjugated NPs achieved a high tumor inhibition in the B16 allograft tumor animal model. The design of these NPs provides a method for delivering cytotoxic ligand to targeting tissue, which may be valuable in cancer therapy.

Analogues of the epoxy resin monomer diglycidyl ether of bisphenol F: effects on contact allergenic potency and cytotoxicity.

PubMed

O'Boyle, Niamh M; Delaine, Tamara; Luthman, Kristina; Natsch, Andreas; Karlberg, Ann-Therese

2012-11-19

Diglycidyl ethers of bisphenol A (DGEBA) and bisphenol F (DGEBF) are widely used as components in epoxy resin thermosetting products. They are known to cause occupational and nonoccupational allergic contact dermatitis. The aim of this study is to investigate analogues of DGEBF with regard to contact allergy and cytotoxicity. A comprehensive knowledge of the structural features that contribute to the allergenic and cytotoxic effects of DGEBF will guide the development of future novel epoxy resin systems with reduced health hazards for those coming into contact with them. It was found that the allergenic effects of DGEBF were dependent on its terminal epoxide groups. In contrast, it was found that the cytotoxicity in monolayer cell culture was dependent not only on the presence of epoxide groups but also on other structural features.

Modification of the fluorescent antibody virus neutralisation test--elimination of the cytotoxic effect for the detection of rabies virus neutralising antibodies.

PubMed

Bedeković, Tomislav; Lemo, Nina; Lojkić, Ivana; Mihaljević, Zeljko; Jungić, Andreja; Cvetnić, Zeljko; Cač, Zeljko; Hostnik, Peter

2013-04-01

The virus neutralisation test is used for the quantitation of specific antibodies in serum samples. However, the success of the test depends on the quality of samples. In the case of poor quality samples, a cytotoxic effect can be observed and the results of the test can be compromised. Additionally, the cytotoxic effect limits the use of different substances, such as muscle extract or liquid from thoracic cavity (thoracic liquid), as a sample for the detection of rabies virus neutralising antibodies in the follow-up of fox oral vaccination campaigns. To eliminate the cytotoxic effect, a modified fluorescent antibody virus neutralisation (mFAVN) test was developed and evaluated. In the mFAVN test, inocula were removed after a 1h and the cytotoxic effect was prevented. According to the results obtained, the specificity of the mFAVN test compared to the FAVN test was 88.8% and the sensitivity was 94.4%. The diagnostic validity of the test was 0.99 (CI=0.98-1.00). To evaluate the possibility of using muscle extract and thoracic liquid as samples for the virus neutralisation test, 102 sera, muscle extract and thoracic liquid samples of dog origin were tested with the mFAVN test. The correlation between sera and muscle extracts was 87.9% (r=0.88, p<0.001). The correlation between sera and thoracic liquid was 94.2% (r=0.94, p<0.001). These findings indicated that both muscle extract and thoracic liquid could be used as samples for detection of rabies virus neutralising antibodies in the follow-up of oral vaccination campaigns. To evaluate the level of elimination of the cytotoxic effect, the 102 samples of sera, muscle extracts and thoracic liquid of dog origin were also tested in parallel using the mFAVN and FAVN tests. In the mFAVN test, no instance of cytotoxic effect was observed in the cells. In the FAVN test, two sera (1.9%), 35 muscle extracts (34.3%) and 56 thoracic liquid samples (54.9%) showed cytotoxic effect. The results of this study strongly suggest that

Cytotoxic and radioprotective effects of Podophyllum hexandrum.

PubMed

Shukla, Sandeep Kumar; Chaudhary, Pankaj; Prem Kumar, Indracanti; Afrin, Farhat; Puri, Satish Chandra; Qazi, Ghulam Nabi; Sharma, Rakesh Kumar

2006-07-01

Podophyllum hexandrum, a herb thriving in Himalayas has already been reported to exhibit antitumor and radioprotective properties. Present study was undertaken to unravel the possible mechanism responsible for the cytotoxic and radioprotective properties of REC-2001, a fraction isolated from the rhizome of P. hexandrum using murine peritoneal macrophages and plasmid DNA as model systems. Cell death, levels of intracellular reactive oxygen species (ROS) and apoptosis were studied employing trypan blue exclusion assay, dichlorofluorescein diacetate and DNA fragmentation assay, respectively. Superoxide anions, hydroxyl radicals and DNA damage were estimated following nitroblue tetrazolium, 2-deoxyribose degradation and plasmid DNA relaxation assays, respectively. Pre-irradiation administration of REC-2001 to peritoneal macrophages in the concentration range of 25-200μg/ml significantly reduced radiation induced ROS generation, DNA damage, apoptosis and cell killing in comparison to radiation control group indicating radioprotective potential. Studies with plasmid DNA indicated the ability of REC-2001 to inhibit 20Gy induced single and double strand breaks further supporting the antioxidative potential. However, REC-2001 in a dose-dependent fashion induced cell death, ROS and DNA fragmentation indicating the cytotoxic nature. REC-2001, in presence of 100μM copper sulfate, generated significant amount of hydroxyl radicals and superoxide anions indicating ability to act as a pro-oxidant in presence of metal ions. The superoxide anion generation was found to be sensitive to metal chelators like EDTA and deferoxamine mesylate (DFR). These results suggest that the ability of REC-2001 to act as a pro-oxidant in presence of metal ions and antioxidant in presence of free radicals might be responsible for cytotoxic and radioprotective properties.

4-Methoxychalcone Enhances Cisplatin-Induced Oxidative Stress and Cytotoxicity by Inhibiting the Nrf2/ARE-Mediated Defense Mechanism in A549 Lung Cancer Cells

PubMed Central

Lim, Juhee; Lee, Sung Ho; Cho, Sera; Lee, Ik-Soo; Kang, Bok Yun; Choi, Hyun Jin

2013-01-01

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcriptional regulator for the protection of cells against oxidative and xenobiotic stresses. Recent studies have demonstrated that high constitutive expression of Nrf2 is observed in many types of cancer cells showing resistance to anti-cancer drugs, suggesting that the suppression of overexpressed Nrf2 could be an attractive therapeutic strategy to overcome cancer drug resistance. In the present study, we aimed to find small molecule compounds that enhance the sensitivity of tumor cells to cisplatin induced cytotoxicity by suppressing Nrf2-mediated defense mechanism. A549 lung cancer cells were shown to be more resistant to the anti-cancer drug cisplatin than HEK293 cells, with higher Nrf2 signaling activity; constitutively high amounts of Nrf2-downstream target proteins were observed in A549 cells. Among the three chalcone derivatives 4-methoxy-chalcone (4-MC), hesperidin methylchalcone, and neohesperidin dihydrochalcone, 4-MC was found to suppress transcriptional activity of Nrf2 in A549 cells but to activate it in HEK293 cells. 4-MC was also shown to down-regulate expression of Nrf2 and the downstream phase II detoxifying enzyme NQO1 in A549 cells. The PI3K/Akt pathway was found to be involved in the 4-MC-induced inhibition of Nrf2/ARE activity in A549 cells. This inhibition of Nrf2 signaling results in the accelerated generation of reactive oxygen species and exacerbation of cytotoxicity in cisplatin-treated A549 cells. Taken together, these results suggest that the small molecule compound 4-MC could be used to enhance the sensitivity of tumor cells to the therapeutic effect of cisplatin through the regulation of Nrf2/ARE signaling. PMID:24046186

4-methoxychalcone enhances cisplatin-induced oxidative stress and cytotoxicity by inhibiting the Nrf2/ARE-mediated defense mechanism in A549 lung cancer cells.

PubMed

Lim, Juhee; Lee, Sung Ho; Cho, Sera; Lee, Ik-Soo; Kang, Bok Yun; Choi, Hyun Jin

2013-10-01

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a key transcriptional regulator for the protection of cells against oxidative and xenobiotic stresses. Recent studies have demonstrated that high constitutive expression of Nrf2 is observed in many types of cancer cells showing resistance to anti-cancer drugs, suggesting that the suppression of overexpressed Nrf2 could be an attractive therapeutic strategy to overcome cancer drug resistance. In the present study, we aimed to find small molecule compounds that enhance the sensitivity of tumor cells to cisplatin induced cytotoxicity by suppressing Nrf2-mediated defense mechanism. A549 lung cancer cells were shown to be more resistant to the anti-cancer drug cisplatin than HEK293 cells, with higher Nrf2 signaling activity; constitutively high amounts of Nrf2-downstream target proteins were observed in A549 cells. Among the three chalcone derivatives 4-methoxy-chalcone (4-MC), hesperidin methylchalcone, and neohesperidin dihydrochalcone, 4-MC was found to suppress transcriptional activity of Nrf2 in A549 cells but to activate it in HEK293 cells. 4-MC was also shown to down-regulate expression of Nrf2 and the downstream phase II detoxifying enzyme NQO1 in A549 cells. The PI3K/Akt pathway was found to be involved in the 4-MC-induced inhibition of Nrf2/ARE activity in A549 cells. This inhibition of Nrf2 signaling results in the accelerated generation of reactive oxygen species and exacerbation of cytotoxicity in cisplatin-treated A549 cells. Taken together, these results suggest that the small molecule compound 4-MC could be used to enhance the sensitivity of tumor cells to the therapeutic effect of cisplatin through the regulation of Nrf2/ARE signaling.

Expression of a CD20-specific chimeric antigen receptor enhances cytotoxic activity of NK cells and overcomes NK-resistance of lymphoma and leukemia cells.

PubMed

Müller, Tina; Uherek, Christoph; Maki, Guitta; Chow, Kai Uwe; Schimpf, Annemarie; Klingemann, Hans-Georg; Tonn, Torsten; Wels, Winfried S

2008-03-01

Despite the clinical success of CD20-specific antibody rituximab, malignancies of B-cell origin continue to present a major clinical challenge, in part due to an inability of the antibody to activate antibody-dependent cell-mediated cytotoxicity (ADCC) in some patients, and development of resistance in others. Expression of chimeric antigen receptors in effector cells operative in ADCC might allow to bypass insufficient activation via FcgammaRIII and other resistance mechanisms that limit natural killer (NK)-cell activity. Here we have generated genetically modified NK cells carrying a chimeric antigen receptor that consists of a CD20-specific scFv antibody fragment, via a flexible hinge region connected to the CD3zeta chain as a signaling moiety. As effector cells we employed continuously growing, clinically applicable human NK-92 cells. While activity of the retargeted NK-92 against CD20-negative targets remained unchanged, the gene modified NK cells displayed markedly enhanced cytotoxicity toward NK-sensitive CD20 expressing cells. Importantly, in contrast to parental NK-92, CD20-specific NK cells efficiently lysed CD20 expressing but otherwise NK-resistant established and primary lymphoma and leukemia cells, demonstrating that this strategy can overcome NK-cell resistance and might be suitable for the development of effective cell-based therapeutics for the treatment of B-cell malignancies.

Cytotoxic effects of octenidine mouth rinse on human fibroblasts and epithelial cells - an in vitro study.

PubMed

Schmidt, J; Zyba, V; Jung, K; Rinke, S; Haak, R; Mausberg, R F; Ziebolz, D

2016-01-01

This study compared the cytotoxicity of a new octenidine mouth rinse (MR) against gingival fibroblasts and epithelial cells with different established MRs. The following MRs were used: Octenidol (OCT), Chlorhexidine 0.2% (CHX), Listerine (LIS), Meridol (MER), Betaisodona (BET); and control (medium only). Human primary gingiva fibroblasts and human primary nasal epithelial cells were cultivated in cell-specific media (2 × 10(5) cells/ml) and treated with MR for 1, 5, and 15 min. Each test was performed 12 times. Metabolism activity was measured using a cytotoxicity assay. A cellometer analyzed cell viability, cell number, and cell diameter. The data were analyzed by two-way analysis of variance with subsequent Dunnett's test and additional t-tests. The cytotoxic effects of all MRs on fibroblasts and epithelial cells compared to the control depended on the contact time (p < 0.001). OCT and BET showed less influence on cell metabolism in fibroblasts than other MRs. OCT also demonstrated comparable but not significant results in epithelial cells (p > 0.005). Cell numbers of both cell types at all contact times revealed that OCT showed a less negative effect (p > 0.005), especially for epithelial cells compared to CHX after 15 min (p < 0.005). OCT and BET showed the best results for viability in fibroblasts (p > 0.005), but MER showed less influence than OCT in epithelial cells (p < 0.005). OCT is a potential alternative to CHX regarding cytotoxicity because of its lower cell-toxic effect against fibroblasts and epithelial cells.

Impact of calcium ion on cytotoxic effect of the boroxine derivative, K2[B3O3F4OH].

PubMed

Ivankovic, Sinisa; Stojkovic, Ranko; Maksimovic, Milka; Galic, Borivoj; Milos, Mladen

2016-01-01

The effect of Ca 2+ ions on the cytotoxic ability of boron heterocyclic compound dipotassium-trioxohydroxytetrafluorotriborate (K 2 [B 3 O 3 F 4 OH]), on in vitro tumor cells (mammary adenocarcinoma 4T1, melanoma B16F10 and squamous cell carcinoma SCCVII) and non-tumoral fibroblast cells (mouse dermal L929 and hamster lung V79) was examined. At small concentrations of Ca 2+ ions (0.42 mM), K 2 [B 3 O 3 F 4 OH] (3.85 mM) has a very strong cytotoxic effect on all cancer cells tested (89.1, 85.6 and 84.6%) and significantly less effect on normal cells (19.5 and 24.2%), respectively. Applying larger concentrations of Ca 2+ ions (9.42-72.42 mM), at the same concentration of K 2 [B 3 O 3 F 4 OH], no significant cytotoxic effect was detected on cancer cells and normal cells investigated. The selective ability of K 2 [B 3 O 3 F 4 OH], in the medium with a low concentration of Ca 2+ ions has a strong cytotoxic effect on cancer cells and very weak effect in normal cells, opens up the possibility of its application in antitumor therapy.

Nitric oxide releasing plasma polymer coating with bacteriostatic properties and no cytotoxic side effects.

PubMed

Michl, Thomas D; Coad, Bryan R; Doran, Michael; Osiecki, Michael; Kafshgari, Morteza Hasanzadeh; Voelcker, Nicolas H; Hüsler, Amanda; Vasilev, Krasimir; Griesser, Hans J

2015-04-25

We report a stable plasma polymer coating, using isopentyl nitrite as a volatile precursor, which releases nitric oxide at bacteriostatic concentrations when contacted with water, inhibiting bacterial growth without cytotoxic side effects to human mesenchymal stem/stromal cells.

In vitro cytotoxicity of iron oxide nanoparticles: effects of chitosan and polyvinyl alcohol as stabilizing agents

NASA Astrophysics Data System (ADS)

Tran, Phong A.; Nguyen, Hiep T.; Fox, Kate; Tran, Nhiem

2018-03-01

Iron oxide magnetic nanoparticles have significant potential in biomedical applications such as in diagnosis, imaging and therapeutic agent delivery. The choice of stabilizers and surface functionalization is important as it is known to strongly influence the cytotoxicity of the nanoparticles. The present study aimed at investigating the effects of surface charges on the cytotoxicity of iron oxide nanoparticles. We used a co-precipitation method to synthesize iron oxide nanoparticles which were then stabilized with either chitosan (CS) or polyvinyl alcohol (PVA) which have net positive charge and zero charge at physiological pH, respectively. The nanoparticles were characterized in terms of size, charges and chemical oxidation state. Cytotoxicity of the nanoparticles was assessed using mouse fibroblast cells and was correlated with surface charges of the nanoparticles and their aggregation.

Low doses of Paclitaxel repress breast cancer invasion through DJ-1/KLF17 signalling pathway.

PubMed

Ismail, Ismail Ahmed; El-Sokkary, Gamal H; Saber, Saber H

2018-04-27

Paclitaxel (taxol) is an important agent against many tumours, including breast cancer. Ample data documents that paclitaxel inhibits breast cancer metastasis while others prove that paclitaxel enhances breast cancer metastasis. The mechanisms by which paclitaxel exerts its action are not well established. This study focuses on the effect of paclitaxel, particularly the low doses on breast cancer metastasis and the mechanisms that regulate it. Current results show that, paclitaxel exerts significant cytotoxicity even at low doses in both MCF-7 and MDA-MB-231 cells. Interestingly, paclitaxel significantly inhibits cell invasion and migration, decreases Snail and increases E-cadherin mRNA expression levels at the indicated low doses. Furthermore, paclitaxel-inhibiting breast cancer metastasis is associated with down-regulation of DJ-1 and ID-1 mRNA expression level with a concurrent increase in KLF17 expression. Under the same experimental conditions, paclitaxel induces KLF17 and concurrently represses ID-1 protein levels. Our results show for the first time that paclitaxel inhibits breast cancer metastasis through regulating DJ-1/KLF17/ID-1 signalling pathway; repressed DJ-1 and ID-1 and enhanced KLF17 expression. © 2018 John Wiley & Sons Australia, Ltd.

Effect of prostaglandin E2 on cytotoxic activity and granzyme A protease release by murine adherent IL-2 activated killer cells.

PubMed

Vaillier, D; Daculsi, R; Gualde, N

1994-04-01

The effects of prostaglandin E2 (PGE2) have been studied on a highly purified population of murine IL-2 activated killer cells obtained by selecting plastic-adherent splenocytes (AK cells) after incubation with high doses of recombinant IL-2. AK cells were highly cytotoxic for YAC-1 target cells. The cytotoxic activity was detectable at one hour after initiation of the cytotoxic assay and then increased with time. Cytotoxic activity of AK cells was inhibited by the addition of PGE2 or forskolin during the cytotoxic assay. When AK cells were generated in the presence of PGE2, the yielding cytotoxic activity was lower than the one expressed by "regular" AK cells but were insensitive to the inhibitory effect of PGE2 even if their lytic capability was still suppressed by forskolin. The presence of PGE2 during the AK cell culture had no effect on the cellular proliferation. Moreover, using tetrazolium-based colorimetric assay which reflects the cellular activation, it was observed that AK cells cultured in presence of PGE2 had an increased capacity to cleave the tetrazolium salt to formazan. Since the cytotoxic activity of killer cells is related to expression of serine esterase enzymes we evaluated the effects of PGE2 on serine esterase (Granzyme A) release after one hour of incubation of AK cells either alone or in presence of PGE2, YAC-1 cells or both. We observed that (i) AK cells spontaneously release granzyme A, (ii) the level of granzyme A was significantly increased when AK cells were incubated either with YAC-1 cells or PGE2 but did not change when YAC-1 cells and PGE2 were both associated with AK cells.

Myeloid Cell COX-2 deletion reduces mammary tumor growth through enhanced cytotoxic T-lymphocyte function

PubMed Central

Chen, Edward P.; Markosyan, Nune; Connolly, Emma; Lawson, John A.; Li, Xuanwen; Grant, Gregory R.; Grosser, Tilo; FitzGerald, Garret A.; Smyth, Emer M.

2014-01-01

Cyclooxygenase-2 (COX-2) expression is associated with poor prognosis across a range of human cancers, including breast cancer. The contribution of tumor cell-derived COX-2 to tumorigenesis has been examined in numerous studies; however, the role of stromal-derived COX-2 is ill-defined. Here, we examined how COX-2 in myeloid cells, an immune cell subset that includes macrophages, influences mammary tumor progression. In mice engineered to selectively lack myeloid cell COX-2 [myeloid-COX-2 knockout (KO) mice], spontaneous neu oncogene-induced tumor onset was delayed, tumor burden reduced, and tumor growth slowed compared with wild-type (WT). Similarly, growth of neu-transformed mammary tumor cells as orthotopic tumors in immune competent syngeneic myeloid-COX-2 KO host mice was reduced compared with WT. By flow cytometric analysis, orthotopic myeloid-COX-2 KO tumors had lower tumor-associated macrophage (TAM) infiltration consistent with impaired colony stimulating factor-1-dependent chemotaxis by COX-2 deficient macrophages in vitro. Further, in both spontaneous and orthotopic tumors, COX-2-deficient TAM displayed lower immunosuppressive M2 markers and this was coincident with less suppression of CD8+ cytotoxic T lymphocytes (CTLs) in myeloid-COX-2 KO tumors. These studies suggest that reduced tumor growth in myeloid-COX-2 KO mice resulted from disruption of M2-like TAM function, thereby enhancing T-cell survival and immune surveillance. Antibody-mediated depletion of CD8+, but not CD4+ cells, restored tumor growth in myeloid-COX-2 KO to WT levels, indicating that CD8+ CTLs are dominant antitumor effectors in myeloid-COX-2 KO mice. Our studies suggest that inhibition of myeloid cell COX-2 can potentiate CTL-mediated tumor cytotoxicity and may provide a novel therapeutic approach in breast cancer therapy. PMID:24590894

Effect of Processing, Post-Harvest Irradiation, and Production System on the Cytotoxicity and Mutagenicity of Vitis labrusca L. Juices in HTC Cells

PubMed Central

Düsman, Elisângela; de Almeida, Igor Vivian; Lucchetta, Luciano; Vicentini, Veronica Elisa Pimenta

2014-01-01

The juices of grapes (Vitis labrusca L.) are similar to the fruit itself because the main constituents of the fruit are present in the juice. However, their quality characteristics may be modified by the harsh technological processes used for the production of integral food, such as production systems of raw materials and post-harvest treatment of grapes with ultraviolet (UV) irradiation. Therefore, the present study analyzed juices produced naturally (by liquefying the fruit) or by the technological process of extraction by steam distillation (90°C) of grapes from organic and conventional production systems that were untreated or treated with UV type C (65.6 J/m2 for 10 minutes). Using cultures of Rattus norvegicus hepatoma cells (HTC) in vitro, cytotoxic effects were assayed by the MTT test and by calculating the cytokinesis blocked proliferation index (CBPI), and mutagenic effects were measured by the cytokinesis block micronucleus assay. The results of the MTT assay and the CBPIs indicated that none of the juices were cytotoxic, including those that induced cell proliferation. The results of the micronucleus assay showed that none of the juices were mutagenic. However, the average number of micronuclei was lower in the juices produced from organic grapes, and cell proliferation, soluble acids and phenolic compounds were significantly higher. Compared with the natural juices, the integral juices of conventional grapes showed a higher average number of micronuclei as well as lower stimulation of cell proliferation and lower levels of bioactive compounds. The results demonstrate a beneficial effect of UV-C irradiation of post-harvest grapes in stimulating the synthesis of nutraceutical compounds without generating cytotoxic or mutagenic substances. Taken together, our findings support the consumption of grape juice and the application of food production techniques that enhance its nutritional value and promote its production, marketing and consumption. PMID

Effect of processing, post-harvest irradiation, and production system on the cytotoxicity and mutagenicity of Vitis labrusca L. juices in HTC cells.

PubMed

Düsman, Elisângela; de Almeida, Igor Vivian; Lucchetta, Luciano; Vicentini, Veronica Elisa Pimenta

2014-01-01

The juices of grapes (Vitis labrusca L.) are similar to the fruit itself because the main constituents of the fruit are present in the juice. However, their quality characteristics may be modified by the harsh technological processes used for the production of integral food, such as production systems of raw materials and post-harvest treatment of grapes with ultraviolet (UV) irradiation. Therefore, the present study analyzed juices produced naturally (by liquefying the fruit) or by the technological process of extraction by steam distillation (90°C) of grapes from organic and conventional production systems that were untreated or treated with UV type C (65.6 J/m² for 10 minutes). Using cultures of Rattus norvegicus hepatoma cells (HTC) in vitro, cytotoxic effects were assayed by the MTT test and by calculating the cytokinesis blocked proliferation index (CBPI), and mutagenic effects were measured by the cytokinesis block micronucleus assay. The results of the MTT assay and the CBPIs indicated that none of the juices were cytotoxic, including those that induced cell proliferation. The results of the micronucleus assay showed that none of the juices were mutagenic. However, the average number of micronuclei was lower in the juices produced from organic grapes, and cell proliferation, soluble acids and phenolic compounds were significantly higher. Compared with the natural juices, the integral juices of conventional grapes showed a higher average number of micronuclei as well as lower stimulation of cell proliferation and lower levels of bioactive compounds. The results demonstrate a beneficial effect of UV-C irradiation of post-harvest grapes in stimulating the synthesis of nutraceutical compounds without generating cytotoxic or mutagenic substances. Taken together, our findings support the consumption of grape juice and the application of food production techniques that enhance its nutritional value and promote its production, marketing and consumption.

Chrysin enhances doxorubicin-induced cytotoxicity in human lung epithelial cancer cell lines: The role of glutathione

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brechbuhl, Heather M.; Kachadourian, Remy; Min, Elysia

We hypothesized that flavonoid-induced glutathione (GSH) efflux through multi-drug resistance proteins (MRPs) and subsequent intracellular GSH depletion is a viable mechanism to sensitize cancer cells to chemotherapies. This concept was demonstrated using chrysin (5–25 μM) induced GSH efflux in human non-small cell lung cancer lines exposed to the chemotherapeutic agent, doxorubicin (DOX). Treatment with chrysin resulted in significant and sustained intracellular GSH depletion and the GSH enzyme network in the four cancer cell types was predictive of the severity of chrysin induced intracellular GSH depletion. Gene expression data indicated a positive correlation between basal MRP1, MRP3 and MRP5 expression andmore » total GSH efflux before and after chrysin exposure. Co-treating the cells for 72 h with chrysin (5–30 μM) and DOX (0.025–3.0 μM) significantly enhanced the sensitivity of the cells to DOX as compared to 72-hour DOX alone treatment in all four cell lines. The maximum decrease in the IC{sub 50} values of cells treated with DOX alone compared to co-treatment with chrysin and DOX was 43% in A549 cells, 47% in H157 and H1975 cells and 78% in H460 cells. Chrysin worked synergistically with DOX to induce cancer cell death. This approach could allow for use of lower concentrations and/or sensitize cancer cells to drugs that are typically resistant to therapy. -- Graphical abstract: Possible mechanisms by which chrysin enhances doxorubicin-induced toxicity in cancer cells. Highlights: ► Chyrsin sustains a significant depletion of GSH levels in lung cancer cells. ► Chyrsin synergistically potentiates doxorubicin-induced cancer cell cytotoxicity. ► Cancer cell sensitivity correlated with GSH and MRP gene network expression. ► This approach could allow for lower side effects and targeting resistant tumors.« less

Effect of irradiation on human T-cell proliferation: low dose irradiation stimulates mitogen-induced proliferation and function of the suppressor/cytotoxic T-cell subset

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gualde, N.; Goodwin, J.S.

1984-04-01

Unfractionated human T cells exposed to 10-50 rad of X irradiation incorporated less (/sup 3/H)thymidine than nonirradiated T cells when subsequently cultured with PHA or Con A. The cytotoxic/suppressor T-cell subset, isolated as either OKT8(+) or OKT4(-) cells, demonstrated significantly enhanced (/sup 3/H)thymidine incorporation in PHA- or Con A-stimulated cultures after exposure to 10-50 rad, compared to unirradiated cells, while the proliferation of the OKT4(+) helper/inducer subset was inhibited by low dose irradiation. It has been previously reported that approximately 30% of the cytotoxic/suppressor subset also stains with OKM1. When the cytotoxic/suppressor subset was further subdivided into OKT4(-), OKM1(+), andmore » OKT4(-), OKM1(-) cells, proliferation of the OKT4(-), OKM1(+) population was inhibited by exposure to 25 rad while proliferation of the OKT4(-), OKM1(-) population was stimulated. The increase in proliferation of the cytotoxic/suppressor T-cell subset after low dose irradiation is paralleled by an increase in suppressor activity of these cells. T cells exposed to 25 rad and then cultured with Con A for 48 hr caused greater inhibition of IgG production when added to fresh autologous lymphocytes stimulated by pokeweed mitogen than did unirradiated cells. Thus, low dose irradiation enhances both the proliferation and function of the human suppressor T-cell subset.« less

Polymer nanoparticles for cross-presentation of exogenous antigens and enhanced cytotoxic T-lymphocyte immune response

PubMed Central

Song, Chanyoung; Noh, Young-Woock; Lim, Yong Taik

2016-01-01

Effective induction of an antigen-specific cytotoxic T lymphocyte (CTL) immune response is one of the key goals of cancer immunotherapy. We report the design and fabrication of polyethylenimine (PEI)-coated polymer nanoparticles (NPs) as efficient antigen-delivery carriers that can induce antigen cross-presentation and a strong CTL response. After synthesis of poly(d,l-lactide-co-glycolide) (PLGA) NPs containing ovalbumin (OVA) by the double-emulsion solvent-evaporation method, cationic-charged PLGA NPs were generated by coating them with PEI. In a methyl tetrazolium salt assay, no discernible cytotoxic effect of PEI-coated PLGA (OVA) NPs was observed. The capacity and mechanism of PEI-coated PLGA (OVA) NPs for antigen delivery and cross-presentation on dendritic cells (DCs) were determined by fluorescence microscopy and flow cytometry. PEI-coated PLGA (OVA) NPs were internalized efficiently via phagocytosis or macropinocytosis in DCs and induced efficient cross-presentation of the antigen on MHC class I molecules via both endosome escape and a lysosomal processing mechanism. The DCs treated with PEI-coated PLGA (OVA) NPs induced a release of IL-2 cytokine from OVA-specific CD8-OVA1.3 T cells more efficiently than DCs treated with PLGA (OVA) NPs. Therefore, the PEI-coated PLGA (OVA) NPs can induce antigen cross-presentation and are expected to be used for induction of a strong CTL immune response and for efficient anticancer immunotherapy. PMID:27540289

Protective effects of Asian green vegetables against oxidant induced cytotoxicity

PubMed Central

Rose, Peter; Ong, Choon Nam; Whiteman, Matt

2005-01-01

AIM: To evaluate the antioxidant and phase II detoxification enzyme inducing ability of green leaf vegetables consumed in Asia. METHODS: The antioxidant properties of six commonly consumed Asian vegetables were determined using the ABTS, DPPH, deoxyribose, PR bleaching and iron- ascorbate induced lipid peroxidation assay. Induce of phase II detoxification enzymes was also determined for each respective vegetable extract. Protection against authentic ONOO- and HOCl mediated cytotoxicity in human colon HCT116 cells was determined using the MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide) viability assay. RESULTS: All of the extracts derived from green leaf vegetables exhibited antioxidant properties, while also having cytoprotective effects against ONOO- and HOCl mediated cytotoxicity. In addition, evaluation of the phase II enzyme inducing ability of each extract, as assessed by quinone reductase and glutathione-S-transferase activities, showed significant variation between the vegetables analyzed. CONCLUSION: Green leaf vegetables are potential sources of antioxidants and phase II detoxification enzyme inducers in the Asian diet. It is likely that consumption of such vegetables is a major source of beneficial phytochemical constituents that may protect against colonic damage. PMID:16437686

Macrolide Antibiotics Exhibit Cytotoxic Effect under Amino Acid-Depleted Culture Condition by Blocking Autophagy Flux in Head and Neck Squamous Cell Carcinoma Cell Lines

PubMed Central

Hirasawa, Kazuhiro; Moriya, Shota; Miyahara, Kana; Kazama, Hiromi; Hirota, Ayako; Takemura, Jun; Abe, Akihisa; Inazu, Masato; Hiramoto, Masaki; Tsukahara, Kiyoaki

2016-01-01

Autophagy, a self-digestive system for cytoplasmic components, is required to maintain the amino acid pool for cellular homeostasis. We previously reported that the macrolide antibiotics azithromycin (AZM) and clarithromycin (CAM) have an inhibitory effect on autophagy flux, and they potently enhance the cytocidal effect of various anticancer reagents in vitro. This suggests that macrolide antibiotics can be used as an adjuvant for cancer chemotherapy. Since cancer cells require a larger metabolic demand than normal cells because of their exuberant growth, upregulated autophagy in tumor cells has now become the target for cancer therapy. In the present study, we examined whether macrolides exhibit cytotoxic effect under an amino acid-starving condition in head and neck squamous cancer cell lines such as CAL 27 and Detroit 562 as models of solid tumors with an upregulated autophagy in the central region owing to hypovascularity. AZM and CAM induced cell death under the amino acid-depleted (AAD) culture condition in these cell lines along with CHOP upregulation, although they showed no cytotoxicity under the complete culture medium. CHOP knockdown by siRNA in the CAL 27 cells significantly suppressed macrolide-induced cell death under the AAD culture condition. CHOP-/- murine embryonic fibroblast (MEF) cell lines also attenuated AZM-induced cell death compared with CHOP+/+ MEF cell lines. Using a tet-off atg5 MEF cell line, knockout of atg5, an essential gene for autophagy, also induced cell death and CHOP in the AAD culture medium but not in the complete culture medium. This suggest that macrolide-induced cell death via CHOP induction is dependent on autophagy inhibition. The cytotoxicity of macrolide with CHOP induction was completely cancelled by the addition of amino acids in the culture medium, indicating that the cytotoxicity is due to the insufficient amino acid pool. These data suggest the possibility of using macrolides for “tumor-starving therapy”. PMID

A Tetrameric Peptide Derived from Bovine Lactoferricin Exhibits Specific Cytotoxic Effects against Oral Squamous-Cell Carcinoma Cell Lines

PubMed Central

Solarte, Víctor A.; Rosas, Jaiver E.; Rivera, Zuly J.; Arango-Rodríguez, Martha L.; García, Javier E.; Vernot, Jean-Paul

2015-01-01

Several short linear peptides derived from cyclic bovine lactoferricin were synthesized and tested for their cytotoxic effect against the oral cavity squamous-cell carcinoma (OSCC) cell lines CAL27 and SCC15. As a control, an immortalized and nontumorigenic cell line, Het-1A, was used. Linear peptides based on the RRWQWR core sequence showed a moderate cytotoxic effect and specificity towards tumorigenic cells. A tetrameric peptide, LfcinB(20–25)4, containing the RRWQWR motif, exhibited greater cytotoxic activity (>90%) in both OSCC cell lines compared to the linear lactoferricin peptide or the lactoferrin protein. Additionally, this tetrameric peptide showed the highest specificity towards tumorigenic cells among the tested peptides. Interestingly, this effect was very fast, with cell shrinkage, severe damage to cell membrane permeability, and lysis within one hour of treatment. Our results are consistent with a necrotic effect rather than an apoptotic one and suggest that this tetrameric peptide could be considered as a new candidate for the therapeutic treatment of OSCC. PMID:26609531

The Chemical Synthesis of Discodermolide

NASA Astrophysics Data System (ADS)

Paterson, I.; Florence, G. J.

The marine sponge-derived polyketide discodermolide is a potent antimitotic agent that represents a promising natural product lead structure in the treatment of cancer. Discodermolide shares the same microtubule-stabilising mechanism of action as Taxol®, inhibits the growth of solid tumours in animal models and shows synergy with Taxol. The pronounced cytotoxicity of discodermolide, which is maintained against cancer cell lines that display resistance to Taxol and other drugs, combined with its scarce availability from its natural source, has fuelled significant academic and industrial interest in devising a practical total synthesis as a means of ensuring a sustainable supply for drug development. This chapter surveys the various total syntheses of discodermolide that have been completed over the period 1993-2007, focusing on the strategies employed for introduction of the multiple stereocentres and achieving control over the alkene geometry, along with the various methods used for realising the pivotal fragment couplings to assemble progressively the full carbon skeleton. This dedicated synthetic effort has triumphed in removing the supply problem for discodermolide, providing sufficient material for extensive biological studies and enabling its early stage clinical development, as well as facilitating SAR studies for lead optimisation.

Evaluation of the cytotoxic and antimutagenic effects of biflorin, an antitumor 1,4 o-naphthoquinone isolated from Capraria biflora L.

PubMed

Vasconcellos, Marne C; Moura, Dinara J; Rosa, Renato M; Machado, Miriana S; Guecheva, Temenouga N; Villela, Izabel; Immich, Bruna F; Montenegro, Raquel C; Fonseca, Aluísio M; Lemos, Telma L G; Moraes, Maria Elisabete A; Saffi, Jenifer; Costa-Lotufo, Letícia V; Moraes, Manoel O; Henriques, João A P

2010-10-01

Biflorin is a natural quinone isolated from Capraria biflora L. Previous studies demonstrated that biflorin inhibits in vitro and in vivo tumor cell growth and presents potent antioxidant activity. In this paper, we report concentration-dependent cytotoxic, genotoxic, antimutagenic, and protective effects of biflorin on Salmonella tiphymurium, yeast Saccharomyces cerevisiae, and V79 mammalian cells, using different approaches. In the Salmonella/microsome assay, biflorin was not mutagenic to TA97a TA98, TA100, and TA102 strains. However, biflorin was able to induce cytotoxicity in haploid S. cerevisiae cells in stationary and exponential phase growth. In diploid yeast cells, biflorin did not induce significant mutagenic and recombinogenic effects at the employed concentration range. In addition, the pre-treatment with biflorin prevented the mutagenic and recombinogenic events induced by hydrogen peroxide (H(2)O(2)) in S. cerevisiae. In V79 mammalian cells, biflorin was cytotoxic at higher concentrations. Moreover, at low concentrations biflorin pre-treatment protected against H(2)O(2)-induced oxidative damage by reducing lipid peroxidation and DNA damage as evaluated by normal and modified comet assay using DNA glycosylases. Our results suggest that biflorin cellular effects are concentration dependent. At lower concentrations, biflorin has significant antioxidant and protective effects against the cytotoxicity, genotoxicity, mutagenicity, and intracellular lipid peroxidation induced by H(2)O(2) in yeast and mammalian cells, which can be attributed to its hydroxyl radical-scavenging property. However, at higher concentrations, biflorin is cytotoxic and genotoxic.

Cytokinetic study of MCF-7 cells treated with commercial and recombinant bromelain.

PubMed

Fouz, Nour; Amid, Azura; Hashim, Yumi Zuhanis Has-Yun

2014-01-01

Breast cancer is a leading cause of death in women. The available chemotherapy drugs have been associated with many side effects. Bromelain has novel medicinal qualities including anti-inflammatory, anti-thrombotic, fibrinolytic and anti-cancer functions. Commercially available bromelain is obtained through tedious methods; therefore, recombinant bromelain may provide a cheaper and simpler choice with similar quality. This study aimed to assess the effects of commercial and recombinant bromelain on the cytokinetic behavior of MCF-7 breast cancer cells and their potential as therapeutic alternatives in cancer treatment. Cytotoxic activities of commercial and recombinant bromelain were determined using (sulforhodamine) SRB assay. Next, cell viability assays were conducted to determine effects of commercial and recombinant bromelain on MCF-7 cell cytokinetic behavior. Finally, the established growth kinetic data were used to modify a model that predicts the effects of commercial and recombinant bromelain on MCF-7 cells. Commercial and recombinant bromelain exerted strong effects towards decreasing the cell viability of MCF-7 cells with IC50 values of 5.13 μg/mL and 6.25 μg/mL, respectively, compared to taxol with an IC50 value of 0.063 μg/mL. The present results indicate that commercial and recombinant bromelain both have anti-proliferative activity, reduced the number of cell generations from 3.92 to 2.81 for commercial bromelain and to 2.86 for recombinant bromelain, while with taxol reduction was to 3.12. Microscopic observation of bromelain-treated MCF-7 cells demonstrated detachment. Inhibition activity was verified with growth rates decreased dynamically from 0.009 h-1 to 0.0059 h-1 for commercial bromelain and to 0.0063 h-1 for recombinant bromelain. Commercial and recombinant bromelain both affect cytokinetics of MCF-7 cells by decreasing cell viability, demonstrating similar strength to taxol.

Cytotoxic and genotoxic effects of defence secretion of Ulomoides dermestoides on A549 cells.

PubMed

Crespo, Rosana; Villaverde, M Luciana; Girotti, Juan R; Güerci, Alba; Juárez, M Patricia; de Bravo, Margarita G

2011-06-14

Ulomoides dermestoides (Fairmaire, 1893) is a cosmopolitan tenebrionid beetle reared by Argentine people who consume them alive as an alternative medicine in the treatment of different illnesses such as asthma, Parkinson's, diabetes, arthritis, HIV and specially cancer. To evaluate the cytotoxicity and DNA damage of the major volatile components released by Ulomoides dermestoides on human lung carcinoma epithelial cell line A549. The defence compounds of Ulomoides dermestoides were extracted with dichloromethane and analyzed and quantified by capillary gas chromatography. The toxicity effects of the beetle's extract against A549 cell line were evaluated. Cytotoxicity was evaluated by MTT test and Trypan blue assay and genotoxicity was evaluated by the comet assay. The synthetic compounds, individually or combined, were also tested in A549 cells and normal mononuclear human cells. The defence compounds of Ulomoides dermestoides extracted with dichloromethane (methyl-1,4-benzoquinones, ethyl-1,4-benzoquinones and 1-pentadecene as major components) showed cytotoxic activity on A549 cells demonstrated by MTT test and Trypan blue assay, with IC(50) values of 0.26equivalent/ml and 0.34equivalent/ml, respectively (1equivalent=amount of components extracted per beetle). The inhibition of A549 cell proliferation with the synthetic blend (1,4-benzoquinone and 1-pentadecene) or 1,4-benzoquinone alone was similar to that obtained with the insect extract. 1-Pentadecene showed no inhibitory effect. Low doses of insect extract or synthetic blend (0.15equivalent/ml) inhibited mononuclear cell proliferation by 72.2±2.7% and induced significant DNA damage both in tumor and mononuclear cells. Results of this study demonstrated that defence compounds of Ulomoides dermestoides reduced cell viability and induced DNA damage. We also concluded that the insect benzoquinones are primarily responsible for inducing cytotoxicity and genotoxicity in culture cells. Copyright © 2011 Elsevier

Cytochrome P450 peroxidase/peroxygenase mediated xenobiotic metabolic activation and cytotoxicity in isolated hepatocytes.

PubMed

Anari, M R; Khan, S; Liu, Z C; O'Brien, P J

1995-12-01

Cytochrome P450 (P450) can utilize organic hydroperoxides and peracids to support hydroxylation and dealkylation of various P450 substrates. However, the biological significance of this P450 peroxygenase/peroxidase activity in the bioactivation of xenobiotics in intact cells has not been demonstrated. We have shown that tert-butyl hydroperoxide (tBHP) markedly enhances 3-20-fold the cytotoxicity of various aromatic hydrocarbons and their phenolic metabolites. The tBHP-enhanced hepatocyte cytotoxicity of 4-nitroanisole (4-NA) and 4-hydroxyanisole (4-HA) was also accompanied by an increase in the hepatocyte O-demethylation of 4-NA and 4-HA up to 7.5- and 21-fold, respectively. Hepatocyte GSH conjugation by 4-HA was also markedly increased by tBHP. An LC/MS analysis of the GSH conjugates identified hydroquinone-GSH and 4-methoxy-catechol:GSH conjugates as the predominant adducts. Pretreatment of hepatocytes with P450 inhibitors, e.g., phenylimidazole, prevented tBHP-enhanced 4-HA metabolism, GSH depletion, and cytotoxicity. In conclusion, hydroperoxides can therefore be used by intact cells to support the bioactivation of xenobiotics through the P450 peroxidase/peroxygenase system.

Localized Irradiation of Cell Membrane by Auger Electrons Is Cytotoxic Through Oxidative Stress-Mediated Nontargeted Effects.

PubMed

Paillas, Salomé; Ladjohounlou, Riad; Lozza, Catherine; Pichard, Alexandre; Boudousq, Vincent; Jarlier, Marta; Sevestre, Samuel; Le Blay, Marion; Deshayes, Emmanuel; Sosabowski, Jane; Chardès, Thierry; Navarro-Teulon, Isabelle; Mairs, Robert J; Pouget, Jean-Pierre

2016-09-10

We investigated whether radiation-induced nontargeted effects are involved in the cytotoxic effects of anticell surface monoclonal antibodies labeled with Auger electron emitters, such as iodine 125 (monoclonal antibodies labeled with (125)I [(125)I-mAbs]). We showed that the cytotoxicity of (125)I-mAbs targeting the cell membrane of p53(+/+) HCT116 colon cancer cells is mainly due to nontargeted effects. Targeted and nontargeted cytotoxicities were inhibited in vitro following lipid raft disruption with Methyl-β-cyclodextrin (MBCD) or filipin or use of radical oxygen species scavengers. (125)I-mAb efficacy was associated with acid sphingomyelinase activation and modulated through activation of the AKT, extracellular signal-related kinase ½ (ERK1/2), p38 kinase, c-Jun N-terminal kinase (JNK) signaling pathways, and also of phospholipase C-γ (PLC-γ), proline-rich tyrosine kinase 2 (PYK-2), and paxillin, involved in Ca(2+) fluxes. Moreover, the nontargeted response induced by directing 5-[(125)I]iodo-2'-deoxyuridine to the nucleus was comparable to that of (125)I-mAb against cell surface receptors. In vivo, we found that the statistical significance of tumor growth delay induced by (125)I-mAb was removed after MBCD treatment and observed oxidative DNA damage beyond the expected Auger electron range. These results suggest the involvement of nontargeted effects in vivo also. Low-energy Auger electrons, such as those emitted by (125)I, have a short tissue range and are usually targeted to the nucleus to maximize their cytotoxicity. In this study, we show that targeting the cancer cell surface with (125)I-mAbs produces a lipid raft-mediated nontargeted response that compensates for the inferior efficacy of non-nuclear targeting. Our findings describe the mechanisms involved in the efficacy of (125)I-mAbs targeting the cancer cell surface. Antioxid. Redox Signal. 25, 467-484.

Cytotoxic Effects of Dillapiole on Embryonic Development of Mouse Blastocysts in Vitro and in Vivo

PubMed Central

Chan, Wen-Hsiung

2014-01-01

We examined the cytotoxic effects of dillapiole, a phenylpropanoid with antileishmanial, anti-inflammatory, antifungal, and acaricidal activities, on the blastocyst stage of mouse embryos, subsequent embryonic attachment and outgrowth in vitro, and in vivo implantation via embryo transfer. Blastocysts treated with 2.5–10 μM dillapiole exhibited a significant increase in apoptosis and corresponding decrease in total cell number. Notably, the implantation success rates of blastocysts pretreated with dillapiole were lower than those of their control counterparts. Moreover, in vitro treatment with 2.5–10 μM dillapiole was associated with increased resorption of post-implantation embryos and decreased fetal weight. Our results collectively indicate that dillapiole induces apoptosis and retards early post-implantation development, both in vitro and in vivo. However, the extent to which this organic compound exerts teratogenic effects on early human development is not known at present. Further studies are required to establish effective protection strategies against the cytotoxic effects of dillapiole. PMID:24933639

In Vitro Comparison of Cytotoxic and Antibacterial Effects of 16 Commercial Toothpastes

PubMed Central

Ghapanchi, Jannan; Kamali, Fereshteh; Moattari, Afagh; Poorshahidi, Sara; Shahin, Esmaiel; Rezazadeh, Fahimeh; Khorshidi, Hooman; Jamshidi, Samira

2015-01-01

Background: Toothpastes are considered as one of the most common and usable cosmetic and hygienic materials. Such materials contain chemicals which may have an adverse effect on oral tissue in humans. The present study aimed to compare the toxic effect of current commercial toothpastes including Iranian products and imported types which are consumed globally on oral epithelial- and HeLa cells as well as to evaluate their antibacterial effect on Streptococcus mutans in Shiraz, Iran. Materials and Methods: In this experimental study, 16 types of commercial toothpastes were prepared, and their effect was determined on primer epithelial cells of the oral cavity and HeLa cells. Toothpastes anti streptococcal property and toxicity were examined in vitro in different intervals of 1, 2, and 5 min. Data collection and analysis were done using one-way analysis of variance. Results: All experimented toothpastes revealed variable toxic effects on cultured cells. Through an increase in the time of exposure with toothpastes, the toxicity of these materials substantially increased (P = 0.005). On the other hand, all tested toothpastes showed varying degrees of anti-streptococcal effect in the laboratory (P = 0.005). Conclusions: The most cytotoxic effect on primer epithelial cells of oral mucosa and HeLa cells, respectively, belongs to Bath, Daroogar2, Latifeh2, Crend, Sehat, Nasim and Aqua fresh toothpastes; however, the least cytotoxic effect on primer epithelial cells of oral mucosa and HeLa cells, respectively, belongs to Pronamel followed by Crest (sensitive), Close-up, Oral-B, Signal, Colgate, Paradent, and AME. PMID:25878477

Prolonged cytotoxic effect of colchicine released from biodegradable microspheres.

PubMed

Muvaffak, Asli; Gurhan, Ismet; Hasirci, Nesrin

2004-11-15

One the main problems of cancer chemotherapy is the unwanted damage to normal cells caused by the high toxicities of anticancer drugs. Any system of controlled drug delivery that would reduce the total amount of drug required, and thus reduce the side effects, would potentially help to improve chemotherapy. In this respect, biodegradable gelatin microspheres were prepared by water/oil emulsion polymerization and by crosslinking with glutaraldehyde (GTA) as the drug-carrier system. Microspheres were loaded with colchicine, a model antimitotic drug, which was frequently used as an antimitotic agent in cancer research involving cell cultures. Microsphere sizes, swelling and degradation properties, drug-release kinetics, and cytotoxities were studied. Swelling characteristics of microspheres changed upon changing GTA concentration. A decrease in swelling values was recorded as GTA crosslink density was increased. In vitro drug release in PBS (0.01M, pH 7.4) showed rapid colchicine release up to approximately 83% (at t = 92 h) for microspheres with low GTA (0.05% v/v), whereas a slower release profile (only approximately 39%) was obtained for microspheres with high GTA (0.50% v/v) content, for the same period. Cytotoxicity tests with MCF-7, HeLa and H-82 cancer cell lines showed that free colchicine was very toxic, showing an approximately 100% lethal effect in both HeLa and H-82 cell lines and more than 50% decrease in viability in MCF-7 cells in 4 days. Indeed, entrapped colchicine indicated similar initial high toxic effect on cell viability in MCF-7 cell line and this effect became more dominant as colchicine continued to be released from microspheres in the same period. In conclusion, the control of the release rate of colchicine from gelatin microspheres was achieved under in vitro conditions by gelatin through the alteration of crosslinking conditions. Indeed, the results suggested the potential application of gelatin microspheres crosslinked with GTA as a

Differentiation of HL-60 cells distinguishes between cytostatic and cytotoxic effects of the alkylphospholipid ET-18-OCH3.

PubMed

Civoli, F; Pauig, S B; Daniel, L W

1996-01-01

The synthetic dialkylphospholipid 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET-18-OCH3) inhibits growth of the acute myelogenous leukemia cell line HL-60. Incubation of HL-60 cells with demethyl-sulfoxide causes the cells to differentiate to a granulocyte-like phenotype and become quiescent. Incubation of the DMSO-treated cells with ET-18-OCH3 results in a reduction in cell numbers due to cytotoxicity. In contrast, treatment of undifferentiated HL-60 cells with lower concentrations of ET-18-OCH3 leads to growth inhibition. These data indicate that the model of differentiated HL-60 cells currently used for the study of resistance to growth inhibition is inappropriate. HL-60 cells can be used to measure growth inhibition and at higher doses cytotoxicity. However, the differentiated, nonproliferative, cells can only be used to measure direct cytotoxicity. Therefore, the results of studies directly comparing the effects of ET-18-OCH3 in proliferative HL-60 cells and quiescent DMSO-treated HL-60 cells should be reevaluated. An evaluation of the effects of low concentrations of ET-18-OCH3 (0.5-1.5 microM) in proliferative HL-60 cells indicated that ET-18-OCH3 was an effective cytostatic agent at nontoxic concentrations. In summary, studies on the mechanism of action of ET-18-OCH3, or related ether lipids, should carefully investigate differences in the effects at cytostatic versus cytotoxic concentrations.

Patent Survey of Resveratrol, Taxol, Podophyllotoxin, Withanolides and Their Derivatives Used in Anticancer Therapy.

PubMed

Routh, Shreya; Nandagopal, Krishnadas

2017-01-01

Resveratrol, taxol, podophyllotoxin, withanolides and their derivatives find applications in anti-cancer therapy. They are plant-derived compounds whose chemical structures and synthesis limit their natural availability and restrict a large-scale industrial production. Hence, their production by various biotechnological approaches may hold promise for a continuous and reliable mode of supply. We review process and product patents in this regard. Accordingly, we provide a general outline to search the freely accessible WIPO, EPO, USPTO and Cambia databases with several keywords and patent codes. We have tabulated both granted and filed patents from the said databases. We retrieved ~40 patents from these databases. Novel biotechnological processes for production of these anticancer compounds include Agrobacterium rhizogenes-mediated hairy root culture, suspension culture, cell culture with elicitors, use of recombinant microorganisms, and bioreactors among others. The results are indicative of being both database-specific as well as queryspecific. A ten-year search window yielded 33 patents. The utility of the search strategy is discussed in the light of biotechnological developments in the field. Those who examine patent literature using similar search strategies may complement their knowledge obtained from perusal of mainstream journal resources. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

New insights into cytotoxicity induced by microcystin-LR, estradiol, and ractopamine with mathematical models: Individual and combined effects.

PubMed

Ma, Min; Pi, Fuwei; Wang, Jiasheng; Ji, Jian; Sun, Xiulan

2017-02-01

Humans are most likely to be exposed to microcystins (MCs) combined with other water pollutants rather than to individual compounds through the consumption of contaminated drinking water or through recreational activities, such as swimming. However, the combined effects of MC-LR, estradiol (EST), and ractopamine (RAC) have not been extensively researched. The goal of this study was to investigate the combined effects of these compounds. For this purpose, cytotoxicity was evaluated in HepG2 cells treated with single or combined doses of MC-LR, EST, and RAC based on concentration addition (CA), independent action (IA), and Chou-Talalay's combination-index (CI) methods. Singly applied MC-LR and EST induced HepG2 cellular proliferation at low-concentration levels (1 × 10 -12 -1 × 10 -9  M), and decreased viability at higher doses of exposure (1 × 10 -9 -1 × 10 -6  M). Exposure to binary or ternary mixtures of MC-LR, EST, and RAC exhibited synergistic effects at high concentrations, irrespective of the models used. In contrast, antagonism was observed for the mixture of MC-LR and EST at relatively low concentrations. A synergistic effect on reactive oxygen species (ROS) generation was observed for the combined drugs at high concentrations. Additionally, the ratio of apoptotic cells was increased more by the combined drugs than the single drugs, consistent with the inhibition of cell viability. The ROS increase after treatment with the combined drugs may enhance cytotoxicity and subsequently lead to cell apoptosis. Given the interactions between MC-LR, EST, and RAC, government regulatory standards for MC-LR should consider the toxicological interactions between MC-LR and other environment pollutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genotoxic and cytotoxic effects of different types of dental cement on normal cultured human lymphocytes.

PubMed

Bakopoulou, A; Mourelatos, D; Tsiftsoglou, A S; Giassin, N P; Mioglou, E; Garefis, P

2009-01-31

In this study we have investigated the genotoxic and cytotoxic effects of eluates derived from different types of commercially available dental cements, including glass ionomer cements (GICs) (Ketac Cem/3M ESPE and GC Fuji I/GC Corp), resin-modified glass ionomer cements (RM-GICs) (RelyX Luting/3M ESPE and Vitrebond/3M ESPE) and dual-cure resin cements (RCs) (Variolink II/ Ivoclar-Vivadent and Panavia F 2.0/Kuraray) on normal cultured human lymphocytes. Lymphocyte primary cultures obtained from blood samples of three healthy donors were exposed to serial dilutions of eluates derived from specimens of each material tested. Metaphases were induced with phytohaemagglutinin, collected after 72h treatment by use of colchicine and stained according to the fluorescence plus giemsa (FPG) procedure. Preparations were scored for sister chromatid exchange (SCE) and chromosomal aberrations (CAs), while the proliferation rate index (PRI) was also calculated. Our results show that eluates derived from the RM-GICs and RCs caused severe genotoxic effects by significantly increasing the frequencies of SCEs and CAs in cultures of peripheral blood lymphocytes and by decreasing the relevant PRI values in a dose-dependent manner, whereas the two GICs caused only minor cytogenetic effects. Eluates of the two RM-GICs (Vitrebond and RelyX) were also very cytotoxic, as the first serial dilutions of both materials caused a complete mitotic arrest in lymphocyte cultures. Overall, the degree of genotoxicity and cytotoxicity caused by dental cements decreased as follows: Viterbond>Rely X>Panavia F 2.0>Variolink II>Ketac Cem=GC Fuji I. These results indicate that different types of dental cement differ extensively in their genotoxic and cytotoxic potential and their ability to affect chromosomal integrity, cell-cycle progression, DNA replication and repair. Although these results cannot be directly extrapolated to the clinical situation, the potential occurrence of adverse effects caused by the

Effects of lipopolysaccharide on interleukin-2-induced cytotoxic activity of murine splenocyte cultures: role of prostaglandin E2 and interferons.

PubMed

Vaillier, D; Daculsi, R; Gualde, N

1992-01-01

Splenocytes cultured for 24 h in the presence of interleukin-2 (IL-2), lipopolysaccharide (LPS) or both together expressed a cytotoxic activity against the YAC-1 lymphoma cell line and to a lesser extent against P815 mastocytoma cells. The association of IL-2 and LPS had an additive effect on induction of cytotoxicity. The IL-2-induced cytotoxic activity lasted for the whole of the culture; however, the addition of LPS at the initiation of the culture increased the cytotoxic activity during its the early phase, the increment being followed by a fall of lytic activity after 72 h of culture. Assessment of interferon (IFN) in the culture supernatants showed (a) a production of IFN gamma by IL-2-supplemented cultures, (b) a more potent IFN production by cultures treated with IL-2 plus LPS (including 20% IFN alpha/beta, (c) and that indomethacin (1 microM) potentiated the effect of either IL-2 or LPS used alone but did not significantly increase the cytotoxic activity of cultures treated with IL-2 plus LPS (the one that produced a high level of IFN). When cultures were treated by an anti-IFN gamma antibody we observed no change in the cytotoxic activity; however, in the presence of anti-IFN alpha/beta serum the cytotoxic activity of cultures treated with IL-2 plus LPS was inhibited after 24 h but stimulated after 72 h. When cultures treated with IL-2 plus LPS were supplemented with both indomethacin and anti-IFN alpha/beta the cytotoxic activity assessed after 72 h of culture was maintained at the same level as that of IL-2-treated cultures, hence the fall after 72 h of the cytotoxicity of cultures initiated in the presence of LPS alone was affected by both the immune serum and the cyclooxygenase inhibitor. Altogether these data show that when splenocytes are cultured for more than 72 h in the presence of IL-2 and LPS their cytotoxic activity decreases, and it is likely that this diminution is linked to the endogenous production of prostaglandin E2 and INF alpha/beta.

Cytotoxic Effects of PEGylated Anti-EGFR Immunoliposomes Combined with Doxorubicin and Rhenium-188 Against Cancer Cells.

PubMed

Hsu, Wei-Chuan; Cheng, Chu-Nian; Lee, Te-Wei; Hwang, Jeng-Jong

2015-09-01

We aimed to construct epidermal growth factor receptor (EGFR)-targeting cetuximab-immunoliposomes (IL-C225) for targeted delivery of doxorubicin and rhenium-188 (Re-188) to EGFR(+) cancer cells. Synthesized IL-C225 was analyzed by dynamic light scattering, transmission electron microscopy, and matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy. Cell binding and internalization were examined using doxorubicin-loaded IL-C225 (DXR-IL-C225) with confocal microscopy. IL-C225 combined with doxorubicin and Re-188 ((188)Re-DXR-IL-C225) was synthesized, and the cytotoxic effects of (188)Re-DXR-IL-C225 were analyzed in EGFR(+) cancer cells using cell viability assays. IL-C225 bound to EGFR on A431 cancer cells and was rapidly internalized. Furthermore, IL-C225 localized within the tumor cells efficiently. (188)Re-DXR-IL-C225 exhibited outstanding cytotoxic effects against EGFR(+) cancer cells in vitro and showed superior cytotoxic effects compared to DXR-IL-C225 or (188)Re-IL-C225 alone. The new formulation of (188)Re-DXR-IL-C225 may be a potential theranostic vehicle for delivery of drugs in the treatment of EGFR-overexpressing human cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

Cytotoxic effects of 2-methoxyestradiol in the hepatocellular carcinoma cell line HepG2.

PubMed

El Naga, Reem N Abou; El-Demerdash, Ebtehal; Youssef, Samar S; Abdel-Naim, Ashraf B; El-Merzabani, Mahmoud

2009-01-01

The study was designed to examine the potential cytotoxicity of 2-methoxyestradiol (2ME2), a natural 17beta-estradiol metabolite, in hepatocellular carcinoma and the possible underlying mechanisms for this cytotoxicity. The cell line HepG2 was treated with different concentrations of 2ME2 for 48 and 72 h. Using the sulforhodamine B assay, HepG2 was sensitive to the cytotoxic effect of 2ME2. 2ME2 induced cell arrest at the G(2)/M phase and a significant high percentage of apoptotic cells compared to the control group. Also, 2ME2 induced a significant increase in caspase 9 enzymatic activity after 48 and 72 h of treatment compared with control values. The DNA laddering was observed only in cells treated for 72 h. Furthermore, 2ME2 induced a significant decrease in the expression levels of vascular endothelial growth factor (VEGF) gene compared to the control values. 2ME2 exerts cytotoxic activity in the HepG2 cell line by preferential cell blocking at the G(2)/M phase as well as induction of apoptosis as evidenced by increased caspase 9 enzymatic activity and observed DNA laddering in 2ME2-treated HepG2 cells. In addition, a reduction in hypervascularity is an important postulated mechanism as indicated by the significant reduction in the expression of VGEF, one of the most important angiogenic factors.

Mechanism of arctigenin-mediated specific cytotoxicity against human lung adenocarcinoma cell lines.

PubMed

Susanti, Siti; Iwasaki, Hironori; Inafuku, Masashi; Taira, Naoyuki; Oku, Hirosuke

2013-12-15

The lignan arctigenin (ARG) from the herb Arctium lappa L. possesses anti-cancer activity, however the mechanism of action of ARG has been found to vary among tissues and types of cancer cells. The current study aims to gain insight into the ARG mediated mechanism of action involved in inhibiting proliferation and inducing apoptosis in lung adenocarcinoma cells. This study also delineates the cancer cell specificity of ARG by comparison with its effects on various normal cell lines. ARG selectively arrested the proliferation of cancer cells at the G0/G1 phase through the down-regulation of NPAT protein expression. This down-regulation occurred via the suppression of either cyclin E/CDK2 or cyclin H/CDK7, while apoptosis was induced through the modulation of the Akt-1-related signaling pathway. Furthermore, a GSH synthase inhibitor specifically enhanced the cytotoxicity of ARG against cancer cells, suggesting that the intracellular GSH content was another factor influencing the susceptibility of cancer cells to ARG. These findings suggest that specific cytotoxicity of ARG against lung cancer cells was explained by its selective modulation of the expression of NPAT, which is involved in histone biosynthesis. The cytotoxicity of ARG appeared to be dependent on the intracellular GSH level. Copyright © 2013 Elsevier GmbH. All rights reserved.

Assessment of antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of titanium oxide: An in-vitro study.

PubMed

Baby, Roshen Daniel; Subramaniam, Siva; Arumugam, Ilakkiya; Padmanabhan, Sridevi

2017-04-01

Our objective was to assess the antibacterial and cytotoxic effects of orthodontic stainless steel brackets coated with different phases of photocatalytic titanium oxide. From a total sample of 115 brackets, 68 orthodontic stainless steel brackets were coated with titanium oxide using a radiofrequency magnetron sputtering machine. The coated brackets were then converted into 34 each of the anatase and rutile phases of titanium oxide. These brackets were subdivided into 4 groups for antibacterial study and 3 groups for cytotoxicity study. Brackets for the antibacterial study were assessed against the Streptococcus mutans species using microbiologic tests. Three groups for the cytotoxicity study were assessed using the thiazolyl tetrazolium bromide assay. The antibacterial study showed that both phases were effective, but the rutile phase of photocatalytic titanium oxide had a greater bactericidal effect than did the anatase phase. The cytotoxicity study showed that the rutile phase had a greater decrease in viability of cells compared with the anatase phase. It is recommended that orthodontic brackets be coated with the anatase phase of titanium oxide since they exhibited a significant antibacterial property and were only slightly cytotoxic. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

Endosulfan decreases cytotoxic activity of nonspecific cytotoxic cells and expression of granzyme gene in Oreochromis niloticus.

PubMed

Téllez-Bañuelos, Martha Cecilia; Ortiz-Lazareno, Pablo Cesar; Jave-Suárez, Luis Felipe; Siordia-Sánchez, Victor Hugo; Bravo-Cuellar, Alejandro; Santerre, Anne; Zaitseva, Galina P

2014-05-01

The effect of the organochlorinated insecticide endosulfan, on the cytotoxic activity of Nile tilapia nonspecific cytotoxic cells (NCC) was assessed. Juvenile Nile tilapia were exposed to endosulfan (7 ppb) for 96 h and splenic NCC were isolated. Flow cytometric phenotyping of NCC was based on the detection of the NCC specific membrane signaling protein NCCRP-1 by using the monoclonal antibody Mab 5C6; granzyme expression was evaluated by quantitative RT-PCR. The cytotoxic activity of sorted NCC on HL-60 tumoral cells was assessed using propidium iodide (PI) staining of DNA in HL-60 nuclei, indicating dead cells. Nile tilapia splenic NCC had the ability to kill HL-60 tumoral cells, however, the exposure to endosulfan significantly reduced, by a 65%, their cytotoxic activity when using the effector:target ratio of 40:1. Additionally, the exposure to endosulfan tended to increase the expression of NCCRP-1, which is involved in NCC antigen recognition and signaling. Moreover, it decreased the expression of the granzyme gene in exposed group as compared with non-exposed group; however significant differences between groups were not detected. In summary, the acute exposure of Nile tilapia to sublethal concentration of endosulfan induces alteration in function of NCC: significant decrease of cytotoxic activity and a tendency to lower granzyme expression, severe enough to compromise the immunity of this species. Copyright © 2014 Elsevier Ltd. All rights reserved.

Protection of vascular endothelial cells from high glucose-induced cytotoxicity by emodin.

PubMed

Gao, Yun; Zhang, Jun; Li, Guilin; Xu, Hong; Yi, Yun; Wu, Qin; Song, Miaomiao; Bee, Yong Mong; Huang, Liping; Tan, Mengxia; Liang, Shangdong; Li, GuoDong

2015-03-01

Induction of endothelial cytotoxicity by hyperglycemia in diabetes has been widely accepted. Emodin is a natural anthraquinone in rhubarb used for treatment of diabetes, but its mechanism of action is not fully understood. This study aimed to examine the potential beneficial effects of emodin on endothelial cytotoxicity caused by high glucose milieu. Culture of human umbilical vein endothelial cells (HUVECs) with high concentrations of glucose resulted in damage to the cells, leading to decreased formazan products by 14-27%, reduced DNA contents by 12-19%, and increased hypodiploid apoptosis by 40-109%. These adverse effects of high glucose could be prevented to a large extent by co-culture with 3 μM of emodin which per se did not affect HUVECs viability. In addition, CCL5 expression of HUVECs cultured in high glucose medium was significantly elevated at both mRNA and protein levels, an effect abolished after treatment with emodin. Moreover, the enhanced adhesion of monocytes to HUVECs (2.1-2.2 fold over control) and elevated chemotaxis activities (2.3-2.4 fold over control) in HUVECs cultured in high glucose medium were completely reversed by emodin. Emodin also suppressed activation of p38 MAPK and ERK1/2 due to high glucose. Our data demonstrated that endothelial cytotoxicity occurred clearly when HUVECs were exposed to high glucose milieu and emodin was able to alleviate the impairments. The protective effects of emodin might be related to the inhibition of CCL5 expression and subsequent cell stress/inflammatory events possibly mediated by activation of MAPK signaling pathways. Copyright © 2015 Elsevier Inc. All rights reserved.

Cytotoxic constituents of Pachyrhizus tuberosus from Peruvian amazon.

PubMed

Leuner, Olga; Havlik, Jaroslav; Budesinsky, Milos; Vrkoslav, Vladimir; Chu, Jessica; Bradshaw, Tracey D; Hummelova, Jana; Miksatkova, Petra; Lapcik, Oldrich; Valterova, Irena; Kokoska, Ladislav

2013-10-01

Investigations into the chemical constituents of the seeds of the neglected tuber crop Pachyrhizus tuberosus (Leguminosae) resulted in the isolation of seven components: five rotenoids [12a-hydroxyerosone (1), 12a-hydroxydolineone (2), erosone (3), 12a-hydroxyrotenone (4) and rotenone (6)], a phenylfuranocoumarin [pachyrrhizine (5)] and an isoflavanone [neotenone (7)]. The compounds were isolated using several chromatography techniques and characterized and verified by NMR and HPLC/MS. The MTT assay was used to examine the selective cytotoxic effects of the methanolic P. tuberosus extract and isolated compounds in two human cancer cell lines [breast (MCF-7) and colorectal (HCT-116)] and in non-transformed human fibroblasts (MRC-5); IC50 values were calculated. The methanolic P. tuberosus extract displayed respectable cytotoxic effects against HCT-116 and MCF-7 cells with IC50 values of 7.3 and 6.3 microg/mL, respectively. Of the compounds, 6 exacted greatest cytotoxicity and selectivity towards the cancer cell lines tested, yielding IC50 values of 0.3 microg/mL against both MCF-7 and HCT-116 cells, and a 6-fold reduced activity against MRC-5 fibroblasts. Compound 4 also demonstrated cytotoxicity against MCF-7 and HCT-116 (1.1 and 1.8 microg/mL, respectively), and reduced cytotoxicity towards MRC-5 cells (7.5 mirog/mL). The results revealed from the in vitro cytotoxic MTT assay are worthy of further antitumor investigation.

Preferential cytotoxicity of bortezomib toward highly malignant human liposarcoma cells via suppression of MDR1 expression and function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hu, Yamei; Wang, Lingxian; Wang, Lu

2015-02-15

Liposarcoma is the most common soft tissue sarcoma with a high risk of relapse. Few therapeutic options are available for the aggressive local or metastatic disease. Here, we report that the clinically used proteasome inhibitor bortezomib exhibits significantly stronger cytotoxicity toward highly malignant human liposarcoma SW872-S cells compared with its parental SW872 cells, which is accompanied by enhanced activation of apoptotic signaling both in vitro and in vivo. Treatment of cells with Jun-N-terminal kinase (JNK) inhibitor SP60015 or the translation inhibitor cycloheximide ameliorated this enhanced apoptosis. Bortezomib inhibited MDR1 expression and function more effectively in SW872-S cells than in SW872more » cells, indicating that the increased cytotoxicity relies on the degree of proteasome inhibition. Furthermore, the pharmacological or genetic inhibition of sarco/endoplasmic reticulum calcium-ATPase (SERCA) 2, which is highly expressed in SW872-S cells, resulted in partial reversal of cell growth inhibition and increase of MDR1 expression in bortezomib-treated SW872-S cells. These results show that bortezomib exhibits preferential cytotoxicity toward SW872-S cells possibly via highly expressed SERCA2-associated MDR1 suppression and suggest that bortezomib may serve as a potent agent for treating advanced liposarcoma. - Highlights: • We compare the cytotoxicity of different drugs between SW872-S and SW872 cells. • Highly malignant liposarcoma cells SW872-S show hypersensitivity to bortezomib. • Apoptotic signaling is robustly enhanced in bortezomib-treated SW872-S cells. • Bortezomib has strong suppression on MDR1 expression and function in SW872-S cells. • Inhibition of SERCA2 protects SW872-S cells from bortezomib.« less

Disease-associated mutations in CNGB3 promote cytotoxicity in photoreceptor-derived cells

PubMed Central

Liu, Chunming; Sherpa, Tshering

2013-01-01

Purpose To determine if achromatopsia associated F525N and T383fsX mutations in the CNGB3 subunit of cone photoreceptor cyclic nucleotide-gated (CNG) channels increases susceptibility to cell death in photoreceptor-derived cells. Methods Photoreceptor-derived 661W cells were transfected with cDNA encoding wild-type (WT) CNGA3 subunits plus WT or mutant CNGB3 subunits, and incubated with the membrane-permeable CNG channel activators 8-(4-chlorophenylthio) guanosine 3′,5′-cyclic monophosphate (CPT-cGMP) or CPT-adenosine 3′,5′-cyclic monophosphate (CPT-cAMP). Cell viability under these conditions was determined by measuring lactate dehydrogenase release. Channel ligand sensitivity was calibrated by patch-clamp recording after expression of WT or mutant channels in Xenopus oocytes. Results Coexpression of CNGA3 with CNGB3 subunits containing F525N or T383fsX mutations produced channels exhibiting increased apparent affinity for CPT-cGMP compared to WT channels. Consistent with these effects, cytotoxicity in the presence of 0.1 μM CPT-cGMP was enhanced relative to WT channels, and the increase in cell death was more pronounced for the mutation with the largest gain-of-function effect on channel gating, F525N. Increased susceptibility to cell death was prevented by application of the CNG channel blocker L-cis-diltiazem. Increased cytotoxicity was also found to be dependent on the presence of extracellular calcium. Conclusions These results indicate a connection between disease-associated mutations in cone CNG channel subunits, altered CNG channel-activation properties, and photoreceptor cytotoxicity. The rescue of cell viability via CNG channel block or removal of extracellular calcium suggests that cytotoxicity in this model depends on calcium entry through hyperactive CNG channels. PMID:23805033

Enhancement of the cytotoxic effects of Cytarabine in synergism with Hesperidine and Silibinin in Acute Myeloid Leukemia: An in-vitro approach.

PubMed

Desai, Urja N; Shah, Krupa P; Mirza, Sheefa H; Panchal, Darshil K; Parikh, Sonia K; Rawal, Rakesh M

2015-01-01

Acute Myeloid Leukemia (AML) therapy continues to be a daunting challenge. Cytosine Arabinoside (Ara-C) is widely used to treat hematological malignancy in humans, but often becomes ineffective because of increased resistance to the drug which may lead to a worse prognosis. Therefore new strategies are needed to understand the mechanism responsible for drug resistance and to develop new therapies to overcome it. Research evidence based on natural compounds used alone or in combination with current chemotherapeutic agents proved their efficacy to treat and prevent cancer. Hesperidin and Silibinin displayed anti-cancer activity against various types of cancers and cell lines and can be used in combination with Cytarabine with the aim to increase cytotoxicy profile and reduction in drug resistance. Experimental Work: Primary cells obtained from AML patient's bone marrow were used to develop in-vitro model and further exposed to various concentration of Cytarabine (10 nM-5000 nM), Hesperidin (0.5 μM-100 μM) and Silibinin (0.5 μM-100 μM) alone and in combination with Cytarabine (Hesperidin-25 μM, Silibinin10 μM) to check cytotoxicity using MTT assay. Synergistic effect was evaluated by Combination Index method. In-vitro study of Hesperidin and Silibinin indicated their cytotoxicity at IC 50 value 50.12 μM and 16.2 μM, respectively. Combination Index study revealed Hesperidin and Silibinin both showed synergistic potential and decreased the IC 50 value of Cytarabine by ~5.9 and ~4.5 folds, respectively. Both natural compounds showed potential anti-leukemic activity hence may be used for AML therapy alone or in combination with other chemotherapeutic agents.

The effect of glycosylation on cytotoxicity of Ibaraki virus nonstructural protein NS3

PubMed Central

URATA, Maho; WATANABE, Rie; IWATA, Hiroyuki

2015-01-01

The cytotoxicity of Ibaraki virus nonstructural protein NS3 was confirmed, and the contribution of glycosylation to this activity was examined by using glycosylation mutants of NS3 generated by site-directed mutagenesis. The expression of NS3 resulted in leakage of lactate dehydrogenase to the culture supernatant, suggesting the cytotoxicity of this protein. The lack of glycosylation impaired the transport of NS3 to the plasma membrane and resulted in reduced cytotoxicity. Combined with the previous observation that NS3 glycosylation was specifically observed in mammalian cells (Urata et al., Virus Research 2014), it was suggested that the alteration of NS3 cytotoxicity through modulating glycosylation is one of the strategies to achieve host specific pathogenisity of Ibaraki virus between mammals and vector arthropods. PMID:26178820

Cytotoxic effects of Pinus eldarica essential oil and extracts on HeLa and MCF-7 cell lines.

PubMed

Sarvmeili, Najmeh; Jafarian-Dehkordi, Abbas; Zolfaghari, Behzad

2016-12-01

Several attempts have so far been made in the search of new anticancer agents of plant origin. Some studies have reported that different species of Pine genus possess cytotoxic activities against various cancer cell lines. In the present study, we evaluated the cytotoxic effects of Pinus eldarica bark and leaf extracts or leaf essential oil on HeLa and MCF-7 tumor cell lines. Hydroalcoholic and phenolic extracts and the essential oil of plant were prepared. Total phenolic contents of the extracts were measured using Folin-Ciocalteu reagent. Essential oil components were determined by gas chromatography-mass spectroscopy (GC-MS). Cytotoxic activity of the extracts and essential oil against HeLa and MCF-7 tumor cell lines were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The polyphenolic content of hydroalcoholic and phenolic extracts of the bark and hydroalcoholic extract of the leaf were 48.31%, 47.2%, and 8.47%, respectively. According to the GC-MS analysis, the major components of the leaf oil of P. eldarica were: β -caryophyllene (14.8%), germacrene D (12.9%), α-terpinenyl acetate (8.15%), α -pinene (5.7%), and -α humulene (5.9%). Bark extracts and leaf essential oil of P. eldarica significantly reduced the viability of both HeLa and MCF-7 cells in a concentration dependent manner. However, leaf extract showed less inhibitory effects against both cell lines. The essential oil of P. eldarica was more cytotoxic than its hydroalcoholic and phenolic extracts. The terpenes and phenolic compounds were probably responsible for cytotoxicity of P. eldarica . Therefore, P. eldarica might have a good potential for active anticancer agents.

Changes in chemical components and cytotoxicity at different maturity stages of Pleurotus eryngii fruiting body.

PubMed

Cui, Fengjie; Li, Yunhong; Yang, Yan; Sun, Wenjing; Wu, Di; Ping, Lifeng

2014-12-31

The present study investigated the changes of the chemical components and cytotoxicity potency at 5 developmental stages of Pleurotus eryngii fruiting body. The carbohydrate and protein contents increased along the maturity of fruiting body while fat content decreased. By comparison, the polysaccharide-protein fractions had the highest antiproliferative effect on SGC-7901 and HepG-2 cells in vitro and increasing activity with growing maturity of P. eryngii fruiting body.The maturation process increased the protein content and acid property through the enhanced relative abundance of Asp, Thr, and Glu in polysaccharide-protein fractions. Further purification and electrophoresis identified that the polysaccharide-protein PEG-1with three subunits possibly was the target cytotoxical component. Our findings proved that mature fruiting body of P. eryngii containing these polysaccharide-proteins possessed highly nutritional values and therapeutical benefits.

Suppression of ErbB-2 in androgen-independent human prostate cancer cells enhances cytotoxic effect by gemcitabine in an androgen-reduced environment.

PubMed

Zhang, Li; Davis, Jeffrey S; Zelivianski, Stanislav; Lin, Fen-Fen; Schutte, Rachel; Davis, Thomas L; Hauke, Ralph; Batra, Surinder K; Lin, Ming-Fong

2009-11-18

We examined the efficacy of combination treatments utilizing cytotoxic drugs plus inhibitors to members of the ErbB-ERK signal pathway in human prostate cancer (PCa) LNCaP C-81 cells. Under an androgen-reduced condition, 50nM gemcitabine caused about 40% growth suppression on C-81 cells. Simultaneous treatment of gemcitabine plus 10microM AG825 produced 60% suppression (p<0.03); while, 85% growth inhibition (p<0.02) was seen if AG825 was added to gemcitabine-treated cells after a 24h-interval. Our data thus showed that in androgen-reduced conditions, inhibition of ErbB-2 increases the cytotoxic efficacy of gemcitabine in PCa cells. This finding has significant implications in the choice of drugs for combination therapy as well as the order of administration for treating cancer patients.

Cytotoxic effects of oosporein isolated from endophytic fungus Cochliobolus kusanoi

PubMed Central

Ramesha, Alurappa; Venkataramana, M.; Nirmaladevi, Dhamodaran; Gupta, Vijai K.; Chandranayaka, S.; Srinivas, Chowdappa

2015-01-01

In the present study, oosporein, a fungal toxic secondary metabolite known to be a toxic agent causing chronic disorders in animals, was isolated from fungus Cochliobolus kusanoi of Nerium oleander L. Toxic effects of oosporein and the possible mechanisms of cytotoxicity as well as the role of oxidative stress in cytotoxicity to Madin-Darby canine kidney kidney cells and RAW 264.7 splene cells were evaluated in vitro. Also to know the possible in vivo toxic effects of oosporein on kidney and spleen, Balb/C mouse were treated with different concentrations of oosporein ranging from 20 to 200 μM). After 24 h of exposure histopathological observations were made to know the effects of oosporein on target organs. Oosporein induced elevated levels of reactive oxygen species (ROS) generation and high levels of malondialdehyde, loss of mitochondrial membrane potential, induced glutathione hydroxylase (GSH) production was observed in a dose depended manner. Effects oosporein on chromosomal DNA damage was assessed by Comet assay, and increase in DNA damage were observed in both the studied cell lines by increasing the oosporein concentration. Further, oosporein treatment to studied cell lines indicated significant suppression of oxidative stress related gene (Superoxide dismutase1 and Catalase ) expression, and increased levels of mRNA expression in apoptosis or oxidative stress inducing genes HSP70, Caspase3, Caspase6, and Caspase9 as measured by quantitative real time-PCR assay. Histopathological examination of oosporein treated mouse kidney and splenocytes further revealed that, oosporein treated target mouse tissues were significantly damaged with that of untreated sam control mice and these effects were in directly proportional to the the toxin dose. Results of the present study reveals that, ROS is the principle event prompting increased oosporein toxicity in studied in vivio and in vitro animal models. The high previlance of these fungi in temperate climates further

Cytotoxicity of natural ginseng glycosides and semisynthetic analogues.

PubMed

Atopkina, L N; Malinovskaya, G V; Elyakov, G B; Uvarova, N I; Woerdenbag, H J; Koulman, A; Pras, N; Potier, P

1999-02-01

The cytotoxicity of natural glycosides from Ginseng, semisynthetic analogues and related triterpenes of the dammarane series, isolated from the leaves of the Far-East species of the genus Betula was studied in order to elucidate structure-activity relationships. Some of the compounds studied were active against the human lung carcinoma GLC4 and adenocarcinoma COLO 320 cell lines. The natural glycosides displayed the lowest cytotoxicity. The triterpenes of the dammarane series used as starting aglycones for semisynthetic derivatives were moderately cytotoxic. The dammarane triterpenes possessing keto groups and their semisynthetic glucosides were the most active compounds tested. Cytotoxic effects of the dammarane glucosides were inversely proportional both to the number of sugars attached to the aglycones and to the number of hydroxy groups of the aglycones. The type of side chain and the configuration of the hydroxy group at C-3 in aglycones did not have a significant influence on the cytotoxicity.

Amino group of salicylic acid exhibits enhanced inhibitory potential against insulin amyloid fibrillation with protective aptitude toward amyloid induced cytotoxicity.

PubMed

Zaman, Masihuz; Khan, Mohsin Vahid; Zakariya, Syed Mohammad; Nusrat, Saima; Meeran, Syed Mustapha; Alam, Parvez; Ajmal, Mohammad Rehan; Wahiduzzaman, Wahiduzzaman; Shahein, Yasser E; Abouelella, Amira M; Khan, Rizwan Hasan

2018-05-01

Protein misfolding and aggregation lead to amyloid generation that in turn may induce cell membrane disruption and leads to cell apoptosis. In an effort to prevent or treat amyloidogenesis, large number of studies has been paying attention on breakthrough of amyloid inhibitors. In the present work, we aim to access the effect of two drugs, that is, acetylsalicylic acid and 5-amino salicylic acid on insulin amyloids by using various biophysical, imaging, cell viability assay, and computational approaches. We established that both drugs reduce the turbidity, light scattering and fluorescence intensity of amyloid indicator dye thioflavin T. Premixing of drugs with insulin inhibited the nucleation phase and inhibitory potential was boosted by increasing the concentration of the drug. Moreover, addition of drugs at the studied concentrations attenuated the insulin fibril induced cytotoxicity in breast cancer cell line MDA-MB-231. Our results highlight the amino group of salicylic acid exhibited enhanced inhibitory effects on insulin fibrillation in comparison to acetyl group. It may be due to presence of amino group that helps it to prolong the nucleation phase with strong binding as well as disruption of aromatic and hydrophobic stacking that plays a key role in amyloid progression. © 2017 Wiley Periodicals, Inc.

MRI-visible liposome nanovehicles for potential tumor-targeted delivery of multimodal therapies

NASA Astrophysics Data System (ADS)

Ren, Lili; Chen, Shizhen; Li, Haidong; Zhang, Zhiying; Ye, Chaohui; Liu, Maili; Zhou, Xin

2015-07-01

Real-time diagnosis and monitoring of disease development, and therapeutic responses to treatment, are possible by theranostic magnetic resonance imaging (MRI). Here we report the synthesis of a multifunctional liposome, which contains Gd-DOTA (an MRI probe), paclitaxel and c(RGDyk) (a targeted peptide). This nanoparticle overcame the insolubility of paclitaxel, reduced the side effects of FDA-approved formulation of PTX-Cre (Taxol®) and improved drug delivery efficiency to the tumor. c(RGDyk) modification greatly enhanced the cytotoxicity of the drug in tumor cells A549. The T1 relaxivity in tumor cells treated with the targeted liposome formulation was increased 16-fold when compared with the non-targeted group. In vivo, the tumors in mice were visualized using T1-weighted imaging after administration of the liposome. Also the tumor growth could be inhibited well after the treatment. Fluorescence images in vitro and ex vivo also showed the targeting effect of this liposome in tumor cells, indicating that this nanovehicle could limit the off-target side effects of anticancer drugs and contrast agents. These findings lay the foundation for further tumor inhibition study and application of this delivery vehicle in cancer therapy settings.

Antibacterial Synthetic Peptides Derived from Bovine Lactoferricin Exhibit Cytotoxic Effect against MDA-MB-468 and MDA-MB-231 Breast Cancer Cell Lines.

PubMed

Vargas Casanova, Yerly; Rodríguez Guerra, Jorge Antonio; Umaña Pérez, Yadi Adriana; Leal Castro, Aura Lucía; Almanzar Reina, Giovanni; García Castañeda, Javier Eduardo; Rivera Monroy, Zuly Jenny

2017-09-29

Linear, dimeric, tetrameric, and cyclic peptides derived from lactoferricin B, containing the RRWQWR motif, were designed, synthesized, purified, and characterized using RP-HPLC chromatography and MALDI-TOF mass spectrometry. The antibacterial activity of the designed peptides against E. coli (ATCC 11775 and 25922) and their cytotoxic effect against MDA-MB-468 and MDA-MB-231 breast cancer cell lines were evaluated. Dimeric and tetrameric peptides showed higher antibacterial activity in both bacteria strains than linear peptides. The dimeric peptide (RRWQWR)₂K-Ahx exhibited the highest antibacterial activity against the tested bacterial strains. Furthermore, the peptides with high antibacterial activity exhibited significant cytotoxic effect against the tested breast cancer cell lines. This cytotoxic effect was fast and dependent on the peptide concentration. The tetrameric molecule containing RRWQWR motif has an optimal cytotoxic effect at a concentration of 22 µM. The evaluated dimeric and tetrameric peptides could be considered as candidates for developing new therapeutic agents against breast cancer. Polyvalence of linear sequences could be considered as a novel and versatile strategy for obtaining molecules with high anticancer activity.

Evaluation of the cytotoxicity of dihydroxytryptamines and 5-hydroxytryptamine antagonists as cytotoxic agents in dimethylhydrazine-induced adenocarcinomata.

PubMed

Tutton, P J; Barkla, D H

1978-01-01

The cytotoxicity of 5,6-dihydroxytryptamine (5,6-DHT), 5,7-dihydroxytryptamine (5,7-DHT), bromolysergic acid diethylamide (BOL), methysergide, and cyproheptadine, and also of 5,6-DHT together with either BOL, methysergide, or cyproheptadine in dimethylhydrazine-induced (DMH) carcinomata of rat colon was evaluated by estimating the percentage of necrotic cells in histological sections of tissues taken 15 h after injection of each of the drugs. In addition, the influence of methysergide and cyproheptadine on the tumour cell mitotic rate was estimated by means of a stathmokinetic technique. Both 5,6-DHT and 5,7-DHT were cytotoxic at each dose tested and for each of these agents the percentage of necrotic cells was directly correlated with the dose of drug used. BOL was not found to be cytotoxic to the colonic carcinomata, whereas both methysergide and cyproheptadine did cause detectable tumour cell necrosis. Methysergide was also found to accelerate tumour cell proliferation, whereas cyproheptadine did not. BOL competitively inhibited the cytotoxicity of 5,6-DHT and neither methysergide nor cyproheptadine potentiated the effect of 5,6 DHT.

Evaluation of the mutagenic and cytotoxic effects of mercurous chloride by the micronuclei technique in golden Syrian hamsters.

PubMed

Cortés-Gutiérrez, Elva I; Cerda-Flores, Ricardo M; González-Ramírez, Diego; Zúñiga-Charles, Miguel A; Lazcano-Martínez, Sigifredo; Sampayo-Reyes, Adriana; Leal-Garza, Carlos H

2004-05-01

The aims of this study were to evaluate the mutagenic and cytotoxic activity of mercurous chloride by the micronucleus technique in vivo on the bone marrow of golden Syrian hamsters after a single i.p. drug administration. Forty male golden Syrian hamsters were classified into eight groups: negative control, positive control and six groups treated with different doses of mercurous chloride (1.25, 2.5, 5, 10, 20 and 40 mg/kg). The negative control was injected with physiological saline i.p. and the positive control with cyclophosphamide at a dose of 80 mg/kg i.p. With respect to mutagenic effect, the average number of micronucleated polychromatic erythrocytes (MPE) in hamsters treated with different doses of mercurous chloride was not significant compared with the negative control. With respect to cytotoxic effect, the average polychromatic erythrocyte/red blood cell ratio showed a significant decrease when the doses were higher than the 2.5 mg/kg dose compared with the negative control. In conclusion, this preliminary study shows a cytotoxic effect but not a mutagenic effect of calomel in vivo at one time point (24 h).

Evaluation of protective and therapeutic effects of dexpanthenol on nasal decongestants and preservatives: results of cytotoxic studies in vitro.

PubMed

Klöcker, Norbert; Rudolph, Peter; Verse, Thomas

2004-01-01

More than 600 million units of nasal decongestants are sold worldwide annually. The cytotoxic and ciliary toxic potential of decongestants, as well as the preservatives of these products, in particular benzalkonium chloride (BKC), is well established. Recently, a beneficial effect of dexpanthenol on the tolerability of the alpha-sympathomimetic xylometazoline and BKC has been described; however, it was unclear if this effect, resulting in significantly higher cell counts in a cytotoxicity study and an increase in ciliary beat frequency in a ciliary toxicity study was of protective or therapeutic nature. The objective of this study was (a) to evaluate whether dexpanthenol would be a useful additive to nasal decongestants to counter the cytotoxic and ciliary toxic effects of the active ingredient and the preservative and (b) to find out whether this beneficial effect is of protective or therapeutic nature. Systematic cytotoxic in vitro tests were performed. After exposure to xylometazoline (0.1%), the effect of dexpanthenol (5%) and BKC (0.01%) was determined by placebo-controlled assessment of cell growth in a human amniotic cell line. Dexpanthenol significantly reduces the toxic effects of xylometazoline regarding cell growth (p < 0.001) when applied in advance. When BKC is eliminated from the nasal sprays, a further significant increase of cell growth was found (p < 0.001). When dexpanthenol is therapeutically applied after xylometazoline, effects on cell growth are only one-half of those of the protective approach. The additive application of dexpanthenol (5%) given before nasal decongestants or preserved nasal sprays is able to improve the tolerability of these substances and to counteract the toxic effects.

CD16A Activation of NK Cells Promotes NK Cell Proliferation and Memory-Like Cytotoxicity against Cancer Cells.

PubMed

Pahl, Jens H W; Koch, Joachim; Götz, Jana-Julia; Arnold, Annette; Reusch, Uwe; Gantke, Thorsten; Rajkovic, Erich; Treder, Martin; Cerwenka, Adelheid

2018-05-01

CD16A is a potent cytotoxicity receptor on human natural killer (NK) cells, which can be exploited by therapeutic bispecific antibodies. So far, the effects of CD16A-mediated activation on NK cell effector functions beyond classical antibody-dependent cytotoxicity have remained poorly elucidated. Here, we investigated NK cell responses after exposure to therapeutic antibodies such as the tetravalent bispecific antibody AFM13 (CD30/CD16A), designed for the treatment of Hodgkin lymphoma and other CD30 + lymphomas. Our results reveal that CD16A engagement enhanced subsequent IL2- and IL15-driven NK cell proliferation and expansion. This effect involved the upregulation of CD25 (IL2Rα) and CD132 (γ c ) on NK cells, resulting in increased sensitivity to low-dose IL2 or to IL15. CD16A engagement initially induced NK cell cytotoxicity. The lower NK cell reactivity observed 1 day after CD16A engagement could be recovered by reculture in IL2 or IL15. After reculture in IL2 or IL15, these CD16A-experienced NK cells exerted more vigorous IFNγ production upon restimulation with tumor cells or cytokines. Importantly, after reculture, CD16A-experienced NK cells also exerted increased cytotoxicity toward different tumor targets, mainly through the activating NK cell receptor NKG2D. Our findings uncover a role for CD16A engagement in priming NK cell responses to restimulation by cytokines and tumor cells, indicative of a memory-like functionality. Our study suggests that combination of AFM13 with IL2 or IL15 may boost NK cell antitumor activity in patients by expanding tumor-reactive NK cells and enhancing NK cell reactivity, even upon repeated tumor encounters. Cancer Immunol Res; 6(5); 517-27. ©2018 AACR . ©2018 American Association for Cancer Research.

Magnetic nanoparticles for enhancing the effectiveness of ultrasonic hyperthermia

NASA Astrophysics Data System (ADS)

Józefczak, A.; Kaczmarek, K.; Hornowski, T.; Kubovčíková, M.; Rozynek, Z.; Timko, M.; Skumiel, A.

2016-06-01

Ultrasonic hyperthermia is a method of cancer treatment in which tumors are exposed to an elevated cytotoxic temperature using ultrasound (US). In conventional ultrasonic hyperthermia, the ultrasound-induced heating in the tumor is achieved through the absorption of wave energy. However, to obtain appropriate temperature in reasonable time, high US intensities, which can have a negative impact on healthy tissues, are required. The effectiveness of US for medical purposes can be significantly improved by using the so-called sonosensitizers, which can enhance the thermal effect of US on the tissue by increasing US absorption. One possible candidate for such sonosensitizers is magnetic nanoparticles with mean sizes of 10-300 nm, which can be efficiently heated because of additional attenuation and scattering of US. Additionally, magnetic nanoparticles are able to produce heat in the alternating magnetic field (magnetic hyperthermia). The synergetic application of ultrasonic and magnetic hyperthermia can lead to a promising treatment modality.

Chitosan as an adjuvant-like substrate for dendritic cell culture to enhance antitumor effects.

PubMed

Lin, Yong-Chong; Lou, Pei-Jen; Young, Tai-Horng

2014-10-01

To induce monocyte differentiation into dendritic cells (DCs) is the essential protocol for the DC-mediated cancer immunotherapy. In this study, monocytes isolated from mouse bone marrow were cultured on chitosan substrate to evaluate the effect of the chitosan culture system on the induction and tumor protection of DCs. Compared to tissue culture polystyrene (TCPS), the chitosan culture system could enhance monocyte aggregation and detachment with increased MTT reduction activity and expression of DC marker CD11c and LPS co-receptor CD14. Moreover, compared to TCPS, chitosan could enhance lipopolysaccharides (LPS)-stimulated DCs to secrete higher amount of IL-12. More importantly, vaccination of tumor lysate-pulsed DCs harvested from chitosan could increase cytotoxic T-lymphocyte (CTL) activity and showed significantly enhanced anti-tumor effect than those from TCPS. Therefore, the current study demonstrated that a protocol to culture DCs on a less-adherent chitosan substrate followed by treatment with tumor lysate has the potential in future DC-based vaccine application. Copyright © 2014 Elsevier Ltd. All rights reserved.

Correlation between luminescence intensity and cytotoxicity in cell-based cytotoxicity assay using luciferase.

PubMed

Wakuri, S; Yamakage, K; Kazuki, Y; Kazuki, K; Oshimura, M; Aburatani, S; Yasunaga, M; Nakajima, Y

2017-04-01

The luciferase reporter assay has become one of the conventional methods for cytotoxicity evaluation. Typically, the decrease of luminescence expressed by a constitutive promoter is used as an index of cytotoxicity. However, to our knowledge, there have been no reports of the correlation between cytotoxicity and luminescence intensity. In this study, to accurately verify the correlation between them, beetle luciferase was stably expressed in human hepatoma HepG2 cells harboring the multi-integrase mouse artificial chromosome vector. We showed that the cytotoxicity assay using luciferase does not depend on the stability of luciferase protein and the kind of constitutive promoter. Next, HepG2 cells in which green-emitting beetle luciferase was expressed under the control of CAG promoter were exposed to 58 compounds. The luminescence intensity and cytotoxicity curves of cells exposed to 48 compounds showed similar tendencies, whereas those of cells exposed to 10 compounds did not do so, although the curves gradually approached each other with increasing exposure time. Finally, we demonstrated that luciferase expressed under the control of a constitutive promoter can be utilized both as an internal control reporter for normalizing a test reporter and for monitoring cytotoxicity when two kinds of luciferases are simultaneously used in the cytotoxicity assay. Copyright © 2017 Elsevier Inc. All rights reserved.

Cytotoxic activity against human neuroblastoma and melanoma cells mediated by IgM antibodies derived from peripheral blood of healthy donors.

PubMed

Devarapu, Satish Kumar; Mamidi, Srinivas; Plöger, Frank; Dill, Othmar; Blixt, Ola; Kirschfink, Michael; Schwartz-Albiez, Reinhard

2016-06-15

A small percentage of healthy donors identified in the Western population carry antibodies in their peripheral blood which convey cytotoxic activity against certain human melanoma and neuroblastoma cell lines. We measured the cytotoxic activity of sera and plasmas from healthy donors on the human neuroblastoma cell line Kelly and various melanoma cell lines. Antibodies of IgM isotype, presumably belonging to the class of naturally occurring antibodies, exerted cytotoxic activity in a complement-dependent fashion. Apart from complement-dependent tumor cell lysis, we observed C3 opsonization in all tumor cell lines upon treatment with cytotoxic plasmas. Cell lines tested primarily expressed membrane complement regulatory proteins (mCRP) CD46, CD55 and CD59 to various extents. Blocking of mCRPs by monoclonal antibodies enhanced cell lysis and opsonization, though some melanoma cells remained resistant to complement attack. Epitopes recognized by cytotoxic antibodies were represented by gangliosides such as GD2 and GD3, as evidenced by cellular sialidase pretreatment and enhanced expression of distinct gangliosides. It remains to be clarified why only a small fraction of healthy persons carry these antitumor cytotoxic antibodies. © 2016 UICC.

Hypoxia-activated cytotoxic agent tirapazamine enhances hepatic artery ligation-induced killing of liver tumor in HBx transgenic mice

PubMed Central

Lin, Wei-Hsiang; Yeh, Shiou-Hwei; Yeh, Kun-Huei; Chen, Kai-Wei; Cheng, Ya-Wen; Su, Tung-Hung; Jao, Ping; Ni, Lin-Chun; Chen, Pei-Jer; Chen, Ding-Shinn

2016-01-01

Transarterial chemoembolization (TACE) is the main treatment for intermediate stage hepatocellular carcinoma (HCC) with Barcelona Clinic Liver Cancer classification because of its exclusive arterial blood supply. Although TACE achieves substantial necrosis of the tumor, complete tumor necrosis is uncommon, and the residual tumor generally rapidly recurs. We combined tirapazamine (TPZ), a hypoxia-activated cytotoxic agent, with hepatic artery ligation (HAL), which recapitulates transarterial embolization in mouse models, to enhance the efficacy of TACE. The effectiveness of this combination treatment was examined in HCC that spontaneously developed in hepatitis B virus X protein (HBx) transgenic mice. We proved that the tumor blood flow in this model was exclusively supplied by the hepatic artery, in contrast to conventional orthotopic HCC xenografts that receive both arterial and venous blood supplies. At levels below the threshold oxygen levels created by HAL, TPZ was activated and killed the hypoxic cells, but spared the normoxic cells. This combination treatment clearly limited the toxicity of TPZ to HCC, which caused the rapid and near-complete necrosis of HCC. In conclusion, the combination of TPZ and HAL showed a synergistic tumor killing activity that was specific for HCC in HBx transgenic mice. This preclinical study forms the basis for the ongoing clinical program for the TPZ-TACE regimen in HCC treatment. PMID:27702890

Activation of microbubbles by low-intensity pulsed ultrasound enhances the cytotoxicity of curcumin involving apoptosis induction and cell motility inhibition in human breast cancer MDA-MB-231 cells.

PubMed

Li, Yixiang; Wang, Pan; Chen, Xiyang; Hu, Jianmin; Liu, Yichen; Wang, Xiaobing; Liu, Quanhong

2016-11-01

Ultrasound and microbubbles-mediated drug delivery has become a promising strategy to promote drug delivery and its therapeutic efficacy. The aim of this research was to assess the effects of microbubbles (MBs)-combined low-intensity pulsed ultrasound (LPUS) on the delivery and cytotoxicity of curcumin (Cur) to human breast cancer MDA-MB-231 cells. Under the experimental condition, MBs raised the level of acoustic cavitation and enhanced plasma membrane permeability; and cellular uptake of Cur was notably improved by LPUS-MBs treatment, aggravating Cur-induced MDA-MB-231 cells death. The combined treatment markedly caused more obvious changes of cell morphology, F-actin cytoskeleton damage and cell migration inhibition. Our results demonstrated that combination of MBs and LPUS may be an efficient strategy for improving anti-tumor effect of Cur, suggesting a potential effective method for antineoplastic therapy. Copyright © 2016 Elsevier B.V. All rights reserved.

Tretinoin-loaded lipid-core nanocapsules overcome the triple-negative breast cancer cell resistance to tretinoin and show synergistic effect on cytotoxicity induced by doxorubicin and 5-fluororacil.

PubMed

Schultze, Eduarda; Buss, Julieti; Coradini, Karine; Begnini, Karine Rech; Guterres, Silvia S; Collares, Tiago; Beck, Ruy Carlos Ruver; Pohlmann, Adriana R; Seixas, Fabiana Kömmling

2017-12-01

Nanostructured drug delivery systems have been extensively studied, mainly for applications in cancer therapy. The advantages of these materials include protection against drug degradation and improvement in both the relative solubility of poorly water soluble drugs as in targeting of therapy, due to the enhanced permeability and retention effect on tumor sites. In this work, we evaluate the antitumor activity of tretinoin-loaded lipid core nanocapsules (TT-LNC) in a tretinoin-resistant breast cancer cell-line, MDA-MB- 231, as well as the synergistic effect of combination of this treatment with 5-FU or DOXO. The inhibition of cell growth was assayed by MTT reduction. Live/Dead assay and DAPI staining evaluated cytotoxicity. Apoptosis was evaluated by Annexin V-PE/7AAD and the effect of chronic exposure was evaluated by colony formation assay. TT-LNC reduced the cell viability even at lower concentrations (1μM) and displayed synergistic effect with 5-FU or DOXO on cytotoxicity and colony formation inhibition. Our work shows a possibility of using nanocapsules to improve the antitumoral activity of TT for its use either alone or in combination with other chemotherapeutic drugs, especially considering the chronic effect. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Cytotoxic effects of Mn(III) N-alkylpyridylporphyrins in the presence of cellular reductant, ascorbate

PubMed Central

Ye, Xiaodong; Fels, Diane; Tovmasyan, Artak; Aird, Katherine M.; Dedeugd, Casey; Allensworth, Jennifer L.; Kos, Ivan; Park, Won; Spasojevic, Ivan; Devi, Gayathri R.; Dewhirst, Mark W.; Leong, Kam W.; Batinic-Haberle, Ines

2012-01-01

Due to the ability to easily accept and donate electrons Mn(III) N-alkylpyridylporphyrins (MnPs) can dismute O2˙−, reduce peroxynitrite, but also generate reactive species and behave as pro-oxidants if conditions favour such action. Herein two ortho isomers, MnTE-2-PyP5+, MnTnHex-2-PyP5+, and a meta isomer MnTnHex-3-PyP5+, which differ greatly with regard to their metal-centered reduction potential, E1/2 (MnIIIP/MnIIP) and lipophilicity, were explored. Employing MnIIIP/MnIIP redox system for coupling with ascorbate, these MnPs catalyze ascorbate oxidation and thus peroxide production. Consequently, cancer oxidative burden may be enhanced, which in turn would suppress its growth. Cytotoxic effects on Caco-2, Hela, 4T1, HCT116 and SUM149 were studied. When combined with ascorbate, MnPs killed cancer cells via peroxide produced outside of the cell. MnTE-2-PyP5+ was the most efficacious catalyst for peroxide production, while MnTnHex-3-PyP5+ is most prone to oxidative degradation with H2, and thus the least efficacious. A 4T1 breast cancer mouse study of limited scope and success was conducted. The tumour oxidative stress was enhanced and its microvessel density reduced when mice were treated either with ascorbate or MnP/ascorbate; the trend towards tumour growth suppression was detected. PMID:21859376

Cytotoxic cells induced after Chlamydia psittaci infection in mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lammert, J.K.

1982-03-01

The ability of spleen cells from Chlamydia psittaci-infected mice to lyse C. psittaci-infected and uninfected target cell monolayers was studied. The cytotoxicity assay used was a terminal label method in which the number of adherent target cells surviving the interaction with effector cells was determined by measuring the uptake of (3H)uridine by such cells. It was observed that in the first few days postinfection (3 to 5), spleens contained cells that lysed infected and uninfected targets with equal efficiency. Subsequently, infected targets were killed primarily. The activity of effector spleen cells for infected targets continued, although at a reduced level,more » beyond 21 days postinfection. Intact effector cells were required since a disruption by sonication resulted in a loss of cytotoxicity. The enhanced killing observed with infected targets was also observed when target cells were sensitized with heat- or UV-inactivated C. psittaci. This study suggests that the induction of cytotoxic cells after C. psittaci infection may contribute to the ability of the host to control multiplication of the microorganism.« less

Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.