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Sample records for polyploidy tumor-cell invasion

  1. The more the better? The role of polyploidy in facilitating plant invasions

    PubMed Central

    te Beest, Mariska; Le Roux, Johannes J.; Richardson, David M.; Brysting, Anne K.; Suda, Jan; Kubešová, Magdalena; Pyšek, Petr

    2012-01-01

    Background Biological invasions are a major ecological and socio-economic problem in many parts of the world. Despite an explosion of research in recent decades, much remains to be understood about why some species become invasive whereas others do not. Recently, polyploidy (whole genome duplication) has been proposed as an important determinant of invasiveness in plants. Genome duplication has played a major role in plant evolution and can drastically alter a plant's genetic make-up, morphology, physiology and ecology within only one or a few generations. This may allow some polyploids to succeed in strongly fluctuating environments and/or effectively colonize new habitats and, thus, increase their potential to be invasive. Scope We synthesize current knowledge on the importance of polyploidy for the invasion (i.e. spread) of introduced plants. We first aim to elucidate general mechanisms that are involved in the success of polyploid plants and translate this to that of plant invaders. Secondly, we provide an overview of ploidal levels in selected invasive alien plants and explain how ploidy might have contributed to their success. Conclusions Polyploidy can be an important factor in species invasion success through a combination of (1) ‘pre-adaptation’, whereby polyploid lineages are predisposed to conditions in the new range and, therefore, have higher survival rates and fitness in the earliest establishment phase; and (2) the possibility for subsequent adaptation due to a larger genetic diversity that may assist the ‘evolution of invasiveness’. Alternatively, polyploidization may play an important role by (3) restoring sexual reproduction following hybridization or, conversely, (4) asexual reproduction in the absence of suitable mates. We, therefore, encourage invasion biologists to incorporate assessments of ploidy in their studies of invasive alien species. PMID:22040744

  2. A novel asymmetric 3D in-vitro assay for the study of tumor cell invasion

    PubMed Central

    2009-01-01

    Background The induction of tumor cell invasion is an important step in tumor progression. Due to the cost and slowness of in-vivo invasion assays, there is need for quantitative in-vitro invasion assays that mimic as closely as possible the tumor environment and in which conditions can be rigorously controlled. Methods We have established a novel asymmetric 3D in-vitro invasion assay by embedding a monolayer of tumor cells between two layers of collagen. The cells were then allowed to invade the upper and lower layers of collagen. To visualize invading cells the gels were sectioned perpendicular to the monolayer so that after seeding the monolayer appears as a thin line precisely defining the origin of invasion. The number of invading tumor cells, their proliferation rate, the distance they traverse and the direction of invasion could then be determined quantitatively. Results The assay was used to compare the invasive properties of several tumor cell types and the results compare well with those obtained by previously described assays. Lysyl-oxidase like protein-2 (Loxl2) is a potent inducer of invasiveness. Using our assay we show for the first time that inhibition of endogenous Loxl2 expression in several types of tumor cells strongly inhibits their invasiveness. We also took advantage of the asymmetric nature of the assay in order to show that fibronectin enhances the invasiveness of breast cancer cells more potently than laminin. The asymmetric properties of the assay were also used to demonstrate that soluble factors derived from fibroblasts can preferentially attract invading breast cancer cells. Conclusion Our assay displays several advantages over previous invasion assays as it is allows the quantitative analysis of directional invasive behavior of tumor cells in a 3D environment mimicking the tumor microenvironment. It should be particularly useful for the study of the effects of components of the tumor microenvironment on tumor cell invasiveness. PMID

  3. Survivin promotes oxidative phosphorylation, subcellular mitochondrial repositioning, and tumor cell invasion

    PubMed Central

    Rivadeneira, Dayana B.; Caino, M. Cecilia; Seo, Jae Ho; Angelin, Alessia; Wallace, Douglas C.; Languino, Lucia R.; Altieri, Dario C.

    2015-01-01

    Survivin promotes cell division and suppresses apoptosis in many human cancers, and increased abundance correlates with metastasis and poor prognosis. Here, we showed that a pool of survivin that localized to the mitochondria of certain tumor cell lines enhanced the stability of oxidative phosphorylation Complex II, which promoted cellular respiration. Survivin also supported the subcellular trafficking of mitochondria to the cortical cytoskeleton of tumor cells, which was associated with increased membrane ruffling, increased focal adhesion complex turnover, and increased tumor cell migration and invasion in cultured cells, and enhanced metastatic dissemination in vivo. Therefore, we found that mitochondrial respiration enhanced by survivin contributes to cancer metabolism, and relocalized mitochondria may provide a “regional” energy source to fuel tumor cell invasion and metastasis. PMID:26268608

  4. Interleukin-8 derived from local tissue-resident stromal cells promotes tumor cell invasion.

    PubMed

    Welte, Gabriel; Alt, Eckhard; Devarajan, Eswaran; Krishnappa, Srinivasalu; Jotzu, Constantin; Song, Yao-Hua

    2012-11-01

    The aim of this study is to evaluate the role of adipose tissue resident stromal cells on tumor cell invasion. Our data show that a subpopulation of adipose tissue derived stromal cells expressing Nestin, NG2, α-smooth muscle actin and PDGFR-α migrate toward the cancer cells. Microarray analysis revealed the upregulation of IL-8 in the migrated cells. We demonstrated that stromal cell derived IL-8 promote the invasion and the anchorage-independent growth of cancer cells. We conclude that human breast cancer cells attract a subpopulation of stromal cells that secrete IL-8 to promote tumor cell invasion in a paracrine fashion.

  5. Endothelial Cells Enhance Tumor Cell Invasion through a Crosstalk Mediated by CXC Chemokine Signaling1

    PubMed Central

    Warner, Kristy A; Miyazawa, Marta; Cordeiro, Mabel M R; Love, William J; Pinsky, Matthew S; Neiva, Kathleen G; Spalding, Aaron C; Nör, Jacques E

    2008-01-01

    Field cancerization involves the lateral spread of premalignant or malignant disease and contributes to the recurrence of head and neck tumors. The overall hypothesis underlying this work is that endothelial cells actively participate in tumor cell invasion by secreting chemokines and creating a chemotactic gradient for tumor cells. Here we demonstrate that conditioned medium from head and neck tumor cells enhance Bcl-2 expression in neovascular endothelial cells. Oral squamous cell carcinoma-3 (OSCC3) and Kaposi's sarcoma (SLK) show enhanced invasiveness when cocultured with pools of human dermal microvascular endothelial cells stably expressing Bcl-2 (HDMEC-Bcl-2), compared to cocultures with empty vector controls (HDMEC-LXSN). Xenografted OSCC3 tumors vascularized with HDMEC-Bcl-2 presented higher local invasion than OSCC3 tumors vascularized with control HDMEC-LXSN. CXCL1 and CXCL8 were upregulated in primary endothelial cells exposed to vascular endothelial growth factor (VEGF), as well as in HDMEC-Bcl-2. Notably, blockade of CXCR2 signaling, but not CXCR1, inhibited OSCC3 and SLK invasion toward endothelial cells. These data demonstrate that CXC chemokines secreted by endothelial cells induce tumor cell invasion and suggest that the process of lateral spread of tumor cells observed in field cancerization is guided by chemotactic signals that originated from endothelial cells. PMID:18283335

  6. PI3K therapy reprograms mitochondrial trafficking to fuel tumor cell invasion.

    PubMed

    Caino, M Cecilia; Ghosh, Jagadish C; Chae, Young Chan; Vaira, Valentina; Rivadeneira, Dayana B; Faversani, Alice; Rampini, Paolo; Kossenkov, Andrew V; Aird, Katherine M; Zhang, Rugang; Webster, Marie R; Weeraratna, Ashani T; Bosari, Silvano; Languino, Lucia R; Altieri, Dario C

    2015-07-14

    Molecular therapies are hallmarks of "personalized" medicine, but how tumors adapt to these agents is not well-understood. Here we show that small-molecule inhibitors of phosphatidylinositol 3-kinase (PI3K) currently in the clinic induce global transcriptional reprogramming in tumors, with activation of growth factor receptors, (re)phosphorylation of Akt and mammalian target of rapamycin (mTOR), and increased tumor cell motility and invasion. This response involves redistribution of energetically active mitochondria to the cortical cytoskeleton, where they support membrane dynamics, turnover of focal adhesion complexes, and random cell motility. Blocking oxidative phosphorylation prevents adaptive mitochondrial trafficking, impairs membrane dynamics, and suppresses tumor cell invasion. Therefore, "spatiotemporal" mitochondrial respiration adaptively induced by PI3K therapy fuels tumor cell invasion, and may provide an important antimetastatic target. PMID:26124089

  7. PI3K therapy reprograms mitochondrial trafficking to fuel tumor cell invasion

    PubMed Central

    Caino, M. Cecilia; Ghosh, Jagadish C.; Chae, Young Chan; Vaira, Valentina; Rivadeneira, Dayana B.; Faversani, Alice; Rampini, Paolo; Kossenkov, Andrew V.; Aird, Katherine M.; Zhang, Rugang; Webster, Marie R.; Weeraratna, Ashani T.; Bosari, Silvano; Languino, Lucia R.; Altieri, Dario C.

    2015-01-01

    Molecular therapies are hallmarks of “personalized” medicine, but how tumors adapt to these agents is not well-understood. Here we show that small-molecule inhibitors of phosphatidylinositol 3-kinase (PI3K) currently in the clinic induce global transcriptional reprogramming in tumors, with activation of growth factor receptors, (re)phosphorylation of Akt and mammalian target of rapamycin (mTOR), and increased tumor cell motility and invasion. This response involves redistribution of energetically active mitochondria to the cortical cytoskeleton, where they support membrane dynamics, turnover of focal adhesion complexes, and random cell motility. Blocking oxidative phosphorylation prevents adaptive mitochondrial trafficking, impairs membrane dynamics, and suppresses tumor cell invasion. Therefore, “spatiotemporal” mitochondrial respiration adaptively induced by PI3K therapy fuels tumor cell invasion, and may provide an important antimetastatic target. PMID:26124089

  8. The role of fibroblast Tiam1 in tumor cell invasion and metastasis

    PubMed Central

    Xu, Kun; Rajagopal, Soumitra; Klebba, Ina; Dong, Shumin; Ji, Yuxin; Liu, Jiewei; Kuperwasser, Charlotte; Garlick, Jonathan A.; Naber, Stephen P.; Buchsbaum, Rachel J.

    2010-01-01

    The co-evolution of tumors and their microenvironment involves bidirectional communication between tumor cells and tumor-associated stroma. Various cell types are present in tumor-associated stroma, of which fibroblasts are the most abundant. The Rac exchange factor Tiam1 is implicated in multiple signaling pathways in epithelial tumor cells and lack of Tiam1 in tumor cells retards tumor growth in Tiam1 knock-out mouse models. Conversely, tumors arising in Tiam1 knock-out mice have increased invasiveness. We have investigated the role of Tiam1 in tumor-associated fibroblasts as a modulator of tumor cell invasion and metastasis, using retroviral delivery of short hairpin RNA to suppress Tiam1 levels in three different experimental models. In spheroid co-culture of mammary epithelial cells and fibroblasts, Tiam1 silencing in fibroblasts led to increased epithelial cell outgrowth into matrix. In tissue-engineered human skin, Tiam1 silencing in dermal fibroblasts led to increased invasiveness of epidermal keratinocytes with premalignant features. In a model of human breast cancer in mice, co-implantation of mammary fibroblasts inhibited tumor invasion and metastasis, which was reversed by Tiam1 silencing in co-injected fibroblasts. These results suggest that stromal Tiam1 may play a role in modulating the effects of the tumor microenvironment on malignant cell invasion and metastasis. This suggests a set of pathways for further investigation, with implications for future therapeutic targets. PMID:20802514

  9. Extracellular microvesicles and invadopodia mediate non-overlapping modes of tumor cell invasion

    PubMed Central

    Sedgwick, Alanna E.; Clancy, James W.; Olivia Balmert, M.; D’Souza-Schorey, Crislyn

    2015-01-01

    Tumor cell invasion requires the molecular and physical adaptation of both the cell and its microenvironment. Here we show that tumor cells are able to switch between the use of microvesicles and invadopodia to facilitate invasion through the extracellular matrix. Invadopodia formation accompanies the mesenchymal mode of migration on firm matrices and is facilitated by Rac1 activation. On the other hand, during invasion through compliant and deformable environments, tumor cells adopt an amoeboid phenotype and release microvesicles. Notably, firm matrices do not support microvesicle release, whereas compliant matrices are not conducive to invadopodia biogenesis. Furthermore, Rac1 activation is required for invadopodia function, while its inactivation promotes RhoA activation and actomyosin contractility required for microvesicle shedding. Suppression of RhoA signaling blocks microvesicle formation but enhances the formation of invadopodia. Finally, we describe Rho-mediated pathways involved in microvesicle biogenesis through the regulation of myosin light chain phosphatase. Our findings suggest that the ability of tumor cells to switch between the aforementioned qualitatively distinct modes of invasion may allow for dissemination across different microenvironments. PMID:26458510

  10. Hypoxia promotes Rab5 activation, leading to tumor cell migration, invasion and metastasis.

    PubMed

    Silva, Patricio; Mendoza, Pablo; Rivas, Solange; Díaz, Jorge; Moraga, Carolina; Quest, Andrew F G; Torres, Vicente A

    2016-05-17

    Hypoxia, a common condition of the tumor microenvironment, is associated with poor patient prognosis, tumor cell migration, invasion and metastasis. Recent evidence suggests that hypoxia alters endosome dynamics in tumor cells, leading to augmented cell proliferation and migration and this is particularly relevant, because endosomal components have been shown to be deregulated in cancer. The early endosome protein Rab5 is a small GTPase that promotes integrin trafficking, focal adhesion turnover, Rac1 activation, tumor cell migration and invasion. However, the role of Rab5 and downstream events in hypoxia remain unknown. Here, we identify Rab5 as a critical player in hypoxia-driven tumor cell migration, invasion and metastasis. Exposure of A549 human lung carcinoma, ZR-75, MDA-MB-231 and MCF-7 human breast cancer and B16-F10 mouse melanoma cells to hypoxia increased Rab5 activation, followed by its re-localization to the leading edge and association with focal adhesions. Importantly, Rab5 was required for hypoxia-driven cell migration, FAK phosphorylation and Rac1 activation, as shown by shRNA-targeting and transfection assays with Rab5 mutants. Intriguingly, the effect of hypoxia on both Rab5 activity and migration was substantially higher in metastatic B16-F10 cells than in poorly invasive B16-F0 cells. Furthermore, exogenous expression of Rab5 in B16-F0 cells predisposed to hypoxia-induced migration, whereas expression of the inactive mutant Rab5/S34N prevented the migration of B16-F10 cells induced by hypoxia. Finally, using an in vivo syngenic C57BL/6 mouse model, Rab5 expression was shown to be required for hypoxia-induced metastasis. In summary, these findings identify Rab5 as a key mediator of hypoxia-induced tumor cell migration, invasion and metastasis.

  11. Hypoxia promotes Rab5 activation, leading to tumor cell migration, invasion and metastasis

    PubMed Central

    Silva, Patricio; Mendoza, Pablo; Rivas, Solange; Díaz, Jorge; Moraga, Carolina; Quest, Andrew F.G.; Torres, Vicente A.

    2016-01-01

    Hypoxia, a common condition of the tumor microenvironment, is associated with poor patient prognosis, tumor cell migration, invasion and metastasis. Recent evidence suggests that hypoxia alters endosome dynamics in tumor cells, leading to augmented cell proliferation and migration and this is particularly relevant, because endosomal components have been shown to be deregulated in cancer. The early endosome protein Rab5 is a small GTPase that promotes integrin trafficking, focal adhesion turnover, Rac1 activation, tumor cell migration and invasion. However, the role of Rab5 and downstream events in hypoxia remain unknown. Here, we identify Rab5 as a critical player in hypoxia-driven tumor cell migration, invasion and metastasis. Exposure of A549 human lung carcinoma, ZR-75, MDA-MB-231 and MCF-7 human breast cancer and B16-F10 mouse melanoma cells to hypoxia increased Rab5 activation, followed by its re-localization to the leading edge and association with focal adhesions. Importantly, Rab5 was required for hypoxia-driven cell migration, FAK phosphorylation and Rac1 activation, as shown by shRNA-targeting and transfection assays with Rab5 mutants. Intriguingly, the effect of hypoxia on both Rab5 activity and migration was substantially higher in metastatic B16-F10 cells than in poorly invasive B16-F0 cells. Furthermore, exogenous expression of Rab5 in B16-F0 cells predisposed to hypoxia-induced migration, whereas expression of the inactive mutant Rab5/S34N prevented the migration of B16-F10 cells induced by hypoxia. Finally, using an in vivo syngenic C57BL/6 mouse model, Rab5 expression was shown to be required for hypoxia-induced metastasis. In summary, these findings identify Rab5 as a key mediator of hypoxia-induced tumor cell migration, invasion and metastasis. PMID:27121131

  12. Hypoxia promotes Rab5 activation, leading to tumor cell migration, invasion and metastasis.

    PubMed

    Silva, Patricio; Mendoza, Pablo; Rivas, Solange; Díaz, Jorge; Moraga, Carolina; Quest, Andrew F G; Torres, Vicente A

    2016-05-17

    Hypoxia, a common condition of the tumor microenvironment, is associated with poor patient prognosis, tumor cell migration, invasion and metastasis. Recent evidence suggests that hypoxia alters endosome dynamics in tumor cells, leading to augmented cell proliferation and migration and this is particularly relevant, because endosomal components have been shown to be deregulated in cancer. The early endosome protein Rab5 is a small GTPase that promotes integrin trafficking, focal adhesion turnover, Rac1 activation, tumor cell migration and invasion. However, the role of Rab5 and downstream events in hypoxia remain unknown. Here, we identify Rab5 as a critical player in hypoxia-driven tumor cell migration, invasion and metastasis. Exposure of A549 human lung carcinoma, ZR-75, MDA-MB-231 and MCF-7 human breast cancer and B16-F10 mouse melanoma cells to hypoxia increased Rab5 activation, followed by its re-localization to the leading edge and association with focal adhesions. Importantly, Rab5 was required for hypoxia-driven cell migration, FAK phosphorylation and Rac1 activation, as shown by shRNA-targeting and transfection assays with Rab5 mutants. Intriguingly, the effect of hypoxia on both Rab5 activity and migration was substantially higher in metastatic B16-F10 cells than in poorly invasive B16-F0 cells. Furthermore, exogenous expression of Rab5 in B16-F0 cells predisposed to hypoxia-induced migration, whereas expression of the inactive mutant Rab5/S34N prevented the migration of B16-F10 cells induced by hypoxia. Finally, using an in vivo syngenic C57BL/6 mouse model, Rab5 expression was shown to be required for hypoxia-induced metastasis. In summary, these findings identify Rab5 as a key mediator of hypoxia-induced tumor cell migration, invasion and metastasis. PMID:27121131

  13. Gelsolin Induces Colorectal Tumor Cell Invasion via Modulation of the Urokinase-Type Plasminogen Activator Cascade

    PubMed Central

    Zhuo, Jingli; Tan, Ee Hong; Yan, Benedict; Tochhawng, Lalchhandami; Jayapal, Manikandan; Koh, Shiuan; Tay, Hwee Kee; Maciver, Sutherland K.; Hooi, Shing Chuan; Salto-Tellez, Manuel; Kumar, Alan Prem; Goh, Yaw Chong; Lim, Yaw Chyn; Yap, Celestial T.

    2012-01-01

    Gelsolin is a cytoskeletal protein which participates in actin filament dynamics and promotes cell motility and plasticity. Although initially regarded as a tumor suppressor, gelsolin expression in certain tumors correlates with poor prognosis and therapy-resistance. In vitro, gelsolin has anti-apoptotic and pro-migratory functions and is critical for invasion of some types of tumor cells. We found that gelsolin was highly expressed at tumor borders infiltrating into adjacent liver tissues, as examined by immunohistochemistry. Although gelsolin contributes to lamellipodia formation in migrating cells, the mechanisms by which it induces tumor invasion are unclear. Gelsolin’s influence on the invasive activity of colorectal cancer cells was investigated using overexpression and small interfering RNA knockdown. We show that gelsolin is required for invasion of colorectal cancer cells through matrigel. Microarray analysis and quantitative PCR indicate that gelsolin overexpression induces the upregulation of invasion-promoting genes in colorectal cancer cells, including the matrix-degrading urokinase-type plasminogen activator (uPA). Conversely, gelsolin knockdown reduces uPA levels, as well as uPA secretion. The enhanced invasiveness of gelsolin-overexpressing cells was attenuated by treatment with function-blocking antibodies to either uPA or its receptor uPAR, indicating that uPA/uPAR activity is crucial for gelsolin-dependent invasion. In summary, our data reveals novel functions of gelsolin in colorectal tumor cell invasion through its modulation of the uPA/uPAR cascade, with potentially important roles in colorectal tumor dissemination to metastatic sites. PMID:22927998

  14. Anti-VEGF treatment reduces blood supply and increases tumor cell invasion in glioblastoma

    PubMed Central

    Keunen, Olivier; Johansson, Mikael; Oudin, Anaïs; Sanzey, Morgane; Rahim, Siti A. Abdul; Fack, Fred; Thorsen, Frits; Taxt, Torfinn; Bartos, Michal; Jirik, Radovan; Miletic, Hrvoje; Wang, Jian; Stieber, Daniel; Stuhr, Linda; Moen, Ingrid; Rygh, Cecilie Brekke; Bjerkvig, Rolf; Niclou, Simone P.

    2011-01-01

    Bevacizumab, an antibody against vascular endothelial growth factor (VEGF), is a promising, yet controversial, drug in human glioblastoma treatment (GBM). Its effects on tumor burden, recurrence, and vascular physiology are unclear. We therefore determined the tumor response to bevacizumab at the phenotypic, physiological, and molecular level in a clinically relevant intracranial GBM xenograft model derived from patient tumor spheroids. Using anatomical and physiological magnetic resonance imaging (MRI), we show that bevacizumab causes a strong decrease in contrast enhancement while having only a marginal effect on tumor growth. Interestingly, dynamic contrast-enhanced MRI revealed a significant reduction of the vascular supply, as evidenced by a decrease in intratumoral blood flow and volume and, at the morphological level, by a strong reduction of large- and medium-sized blood vessels. Electron microscopy revealed fewer mitochondria in the treated tumor cells. Importantly, this was accompanied by a 68% increase in infiltrating tumor cells in the brain parenchyma. At the molecular level we observed an increase in lactate and alanine metabolites, together with an induction of hypoxia-inducible factor 1α and an activation of the phosphatidyl-inositol-3-kinase pathway. These data strongly suggest that vascular remodeling induced by anti-VEGF treatment leads to a more hypoxic tumor microenvironment. This favors a metabolic change in the tumor cells toward glycolysis, which leads to enhanced tumor cell invasion into the normal brain. The present work underlines the need to combine anti-angiogenic treatment in GBMs with drugs targeting specific signaling or metabolic pathways linked to the glycolytic phenotype. PMID:21321221

  15. PI3K{gamma} activation by CXCL12 regulates tumor cell adhesion and invasion

    SciTech Connect

    Monterrubio, Maria; Mellado, Mario; Carrera, Ana C.

    2009-10-16

    Tumor dissemination is a complex process, in which certain steps resemble those in leukocyte homing. Specific chemokine/chemokine receptor pairs have important roles in both processes. CXCL12/CXCR4 is the most commonly expressed chemokine/chemokine receptor pair in human cancers, in which it regulates cell adhesion, extravasation, metastatic colonization, angiogenesis, and proliferation. All of these processes require activation of signaling pathways that include G proteins, phosphatidylinositol-3 kinase (PI3K), JAK kinases, Rho GTPases, and focal adhesion-associated proteins. We analyzed these pathways in a human melanoma cell line in response to CXCL12 stimulation, and found that PI3K{gamma} regulates tumor cell adhesion through mechanisms different from those involved in cell invasion. Our data indicate that, following CXCR4 activation after CXCL12 binding, the invasion and adhesion processes are regulated differently by distinct downstream events in these signaling cascades.

  16. Sortilin is associated with breast cancer aggressiveness and contributes to tumor cell adhesion and invasion

    PubMed Central

    Roselli, Séverine; Pundavela, Jay; Demont, Yohann; Faulkner, Sam; Keene, Sheridan; Attia, John; Jiang, Chen Chen; Zhang, Xu Dong; Walker, Marjorie M.; Hondermarck, Hubert

    2015-01-01

    The neuronal membrane protein sortilin has been reported in a few cancer cell lines, but its expression and impact in human tumors is unclear. In this study, sortilin was analyzed by immunohistochemistry in a series of 318 clinically annotated breast cancers and 53 normal breast tissues. Sortilin was detected in epithelial cells, with increased levels in cancers, as compared to normal tissues (p = 0.0088). It was found in 79% of invasive ductal carcinomas and 54% of invasive lobular carcinomas (p < 0.0001). There was an association between sortilin expression and lymph node involvement (p = 0.0093), suggesting a relationship with metastatic potential. In cell culture, sortilin levels were higher in cancer cell lines compared to non-tumorigenic breast epithelial cells and siRNA knockdown of sortilin inhibited cancer cell adhesion, while proliferation and apoptosis were not affected. Breast cancer cell migration and invasion were also inhibited by sortilin knockdown, with a decrease in focal adhesion kinase and SRC phosphorylation. In conclusion, sortilin participates in breast tumor aggressiveness and may constitute a new therapeutic target against tumor cell invasion. PMID:25871389

  17. Plasminogen activator system modulates invasive capacity and proliferation in prostatic tumor cells.

    PubMed

    Festuccia, C; Dolo, V; Guerra, F; Violini, S; Muzi, P; Pavan, A; Bologna, M

    1998-08-01

    The malignant phenotype of prostatic tumor cells correlates with the expression of both uPA and its cell-membrane receptor (uPAR); however, there is little information concerning the role of cell-bound uPA in matrix degradation and invasion. Our results suggest that cell-associated uPA plays a key role in regulating the amount of plasmin present at the surface of prostatic carcinoma (PRCA) cells and show that differential production of uPA corresponds with the capacity to bind and activate plasminogen. In addition, we provide direct evidence that both uPA secretion and the presence of uPA-uPAR complexes characterize the invasive phenotype of PRCA cells and suggest the existence of several pathways by which tumor cells acquire plasmin activity. LNCaP cells (which do not produce uPA but express uPAR) may activate plasmin through exogenous uPA. In vivo, the source of uPA may be infiltrating macrophages and/or fibroblasts as observed in several other systems. PAI-1 accumulation in the conditioned medium (CM) limits plasmin action to the pericellular microenvironment. Our results indicate that MMP-9 and MMP-2 are also activated by plasmin generated by cell-bound but not by soluble, extracellular uPA. Plasmin activation and triggering of the proteolytic cascade involved in Matrigel invasion is blocked by antibodies against uPA (especially by anti- A-chain of uPA which interacts with uPAR) and by PA inhibitors such as p-aminobenzamidine which may regulate levels of cell-bound uPA. uPA may also regulate growth in PRCA cells. Indeed, antibodies against uPA A-chain (and also p-aminobenzamidine treatment) interfere with the ATF domain and inhibit cell growth in uPA-producing PC3 and DU145 prostate cancer cell lines, whereas exogenous uPA (HMW-uPA with ATF) induces growth of LNCaP prostate tumor cell line. These data support the hypothesis that in prostatic cancer patients at risk of progression, uPA/plasmin blockade may be of therapeutic value by blocking both growth of the

  18. Rab'ing tumor cell migration and invasion: focal adhesion disassembly driven by Rab5.

    PubMed

    Torres, Vicente A

    2014-01-01

    The small GTPase Rab5 has been extensively studied in the context of endocytic trafficking because it is critical in the regulation of early endosome dynamics. In addition to this canonical role, evidence obtained in recent years implicates Rab5 in the regulation of cell migration. This novel role of Rab5 is based not only on an indirect relationship between cell migration and endosomal trafficking as separate processes, but also on the direct regulation of signaling proteins implicated in cell migration. However, the precise mechanisms underlying this connection have remained elusive. Recent studies have shown that the activation of Rab5 is a critical event for maintaining the dynamics of focal adhesions, which is fundamental in regulating not only cell migration but also tumor cell invasion.

  19. Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells

    SciTech Connect

    Heisel, M.A.; Laug, W.E.; Stowe, S.M.; Jones, P.A.

    1984-06-01

    Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation.

  20. Effects of X-irradiation on artificial blood vessel wall degradation by invasive tumor cells.

    PubMed

    Heisel, M A; Laug, W E; Stowe, S M; Jones, P A

    1984-06-01

    Artificial vessel wall cultures, constructed by growing arterial endothelial cells on preformed layers of rat smooth muscle cells, were used to evaluate the effects of X-irradiation on tumor cell-induced tissue degradation. Bovine endothelial cells had radiation sensitivities similar to those of rat smooth muscle cells. Preirradiation of smooth muscle cells, before the addition of human fibrosarcoma (HT 1080) cells, did not increase the rate of degradation and destruction by the invasive cells. However, the degradation rate was decreased if the cultures were irradiated after the addition of HT 1080 cells. The presence of bovine endothelial cells markedly inhibited the destructive abilities of fibrosarcoma cells, but preirradiation of artificial vessel walls substantially decreased their capabilities to resist HT 1080-induced lysis. These findings suggest that the abilities of blood vessels to limit extravasation may be compromised by ionizing radiation.

  1. Inhibition of tumor-cell invasion with chlorotoxin-bound superparamagnetic nanoparticles.

    PubMed

    Veiseh, Omid; Gunn, Jonathan W; Kievit, Forrest M; Sun, Conroy; Fang, Chen; Lee, Jerry S H; Zhang, Miqin

    2009-02-01

    Nanoparticles have been investigated as drug delivery vehicles, contrast agents, and multifunctional devices for patient care. Current nanoparticle-based therapeutic strategies for cancer treatment are mainly based on delivery of chemotherapeutic agents to induce apoptosis or DNA/siRNA to regulate oncogene expression. Here, a nanoparticle system that demonstrates an alternative approach to the treatment of cancers through the inhibition of cell invasion, while serving as a magnetic resonance and optical imaging contrast agent, is presented. The nanoparticle comprises an iron oxide nanoparticle core conjugated with an amine-functionalized poly(ethylene glycol) silane and a small peptide, chlorotoxin (CTX), which enables the tumor cell-specific binding of the nanoparticle. It is shown that the nanoparticle exhibits substantially enhanced cellular uptake and an invasion inhibition rate of approximately 98% compared to unbound CTX ( approximately 45%). Significantly, the investigation from flow cytometry analysis, transmission electron microscopy, and fluorescent imaging reveals that the CTX-enabled nanoparticles deactivated the membrane-bound matrix metalloproteinase 2 (MMP-2) and induced increased internalization of lipid rafts that contain surface-expressed MMP-2 and volume-regulating ion channels through receptor-mediated endocytosis, leading to enhanced prohibitory effects. Since upregulation and activity of MMP-2 have been observed in tumors of neuroectodermal origin, and in cancers of the breast, colon, skin, lung, prostate, ovaries, and a host of others, this nanoparticle system can be potentially used for non-invasive diagnosis and treatment of a variety of cancer types.

  2. Regulation of V-ATPase assembly and function of V-ATPases in tumor cell invasiveness.

    PubMed

    McGuire, Christina; Cotter, Kristina; Stransky, Laura; Forgac, Michael

    2016-08-01

    V-ATPases are ATP-driven proton pumps that function within both intracellular compartments and the plasma membrane in a wide array of normal physiological and pathophysiological processes. V-ATPases are composed of a peripheral V(1) domain that hydrolyzes ATP and an integral V(0) domain that transports protons. Regulated assembly of the V-ATPase represents an important mechanism of regulating V-ATPase activity in response to a number of environmental cues. Our laboratory has demonstrated that glucose-dependent assembly of the V-ATPase complex in yeast is controlled by the Ras/cAMP/PKA pathway. By contrast, increased assembly of the V-ATPase during dendritic cell maturation involves the PI-3 kinase and mTORC1 pathways. Recently, we have shown that amino acids regulate V-ATPase assembly in mammalian cells, possibly as a means to maintain adequate levels of amino acids upon nutrient starvation. V-ATPases have also been implicated in cancer cell survival and invasion. V-ATPases are targeted to different cellular membranes by isoforms of subunit a, with a3 targeting V-ATPases to the plasma membrane of osteoclasts. We have shown that highly invasive human breast cancer cell lines express higher levels of the a3 isoform than poorly invasive lines and that knockdown of a3 reduces both expression of V-ATPases at the plasma membrane and in vitro invasion of breast tumor cells. Moreover, overexpression of a3 in a non-invasive breast epithelial line increases both plasma membrane V-ATPases and in vitro invasion. Finally, specific ablation of plasma membrane V-ATPases in highly invasive human breast cancer cells using either an antibody or small molecule approach inhibits both in vitro invasion and migration. These results suggest that plasma membrane and a3-containing V-ATPases represent a novel and important target in the development of therapeutics to limit breast cancer metastasis. This article is part of a Special Issue entitled 'EBEC 2016: 19th European Bioenergetics

  3. Multi-photon imaging of tumor cell invasion in an orthotopic mouse model of oral squamous cell carcinoma.

    PubMed

    Gatesman Ammer, Amanda; Hayes, Karen E; Martin, Karen H; Zhang, Lingqing; Spirou, George A; Weed, Scott A

    2011-07-25

    Loco-regional invasion of head and neck cancer is linked to metastatic risk and presents a difficult challenge in designing and implementing patient management strategies. Orthotopic mouse models of oral cancer have been developed to facilitate the study of factors that impact invasion and serve as model system for evaluating anti-tumor therapeutics. In these systems, visualization of disseminated tumor cells within oral cavity tissues has typically been conducted by either conventional histology or with in vivo bioluminescent methods. A primary drawback of these techniques is the inherent inability to accurately visualize and quantify early tumor cell invasion arising from the primary site in three dimensions. Here we describe a protocol that combines an established model for squamous cell carcinoma of the tongue (SCOT) with two-photon imaging to allow multi-vectorial visualization of lingual tumor spread. The OSC-19 head and neck tumor cell line was stably engineered to express the F-actin binding peptide LifeAct fused to the mCherry fluorescent protein (LifeAct-mCherry). Fox1(nu/nu) mice injected with these cells reliably form tumors that allow the tongue to be visualized by ex-vivo application of two-photon microscopy. This technique allows for the orthotopic visualization of the tumor mass and locally invading cells in excised tongues without disruption of the regional tumor microenvironment. In addition, this system allows for the quantification of tumor cell invasion by calculating distances that invaded cells move from the primary tumor site. Overall this procedure provides an enhanced model system for analyzing factors that contribute to SCOT invasion and therapeutic treatments tailored to prevent local invasion and distant metastatic spread. This method also has the potential to be ultimately combined with other imaging modalities in an in vivo setting.

  4. Polyethylenimine-coated SPION exhibits potential intrinsic anti-metastatic properties inhibiting migration and invasion of pancreatic tumor cells.

    PubMed

    Mulens-Arias, Vladimir; Rojas, José Manuel; Pérez-Yagüe, Sonia; Morales, María del Puerto; Barber, Domingo F

    2015-10-28

    Due to its aggressive behavior, pancreatic cancer is one of the principal causes of cancer-related deaths. The highly metastatic potential of pancreatic tumor cells demands the development of more effective anti-metastatic approaches for this disease. Although polyethylenimine-coated superparamagnetic iron oxide nanoparticles (PEI-coated SPIONs) have been studied for their utility as transfection agents, little is known of their effect on tumor cell biology. Here we demonstrated that PEI-coated SPIONs have potent inhibitory effects on pancreatic tumor cell migration/invasion, through inhibition of Src kinase and decreased expression of MT1-MMP and MMP2 metalloproteinases. When treated with PEI-coated SPIONs, the pancreatic tumor cell line Pan02 showed reduced invadosome density and thus, a decrease in their ability to invade through basement membrane. These nanoparticles temporarily downmodulated microRNA-21, thereby upregulating the cell migration inhibitors PTEN, PDCD4 and Sprouty-1. PEI-coated SPIONs thus show intrinsic, possibly anti-metastatic properties for modulating pancreatic tumor cell migration machinery, which indicates their potential as anti-metastatic agents for treatment of pancreatic cancer.

  5. Biodegradable nano-films for capture and non-invasive release of circulating tumor cells

    PubMed Central

    Park, Myoung-Hwan; Castleberry, Steven; Deng, Jason Z.; Hsu, Bryan; Mayner, Sarah; Jensen, Anne E.; Sequist, Lecia V.; Maheswaran, Shyamala; Haber, Daniel A.; Toner, Mehmet; Stott, Shannon L.; Hammond, Paula T.

    2016-01-01

    Selective isolation and purification of circulating tumor cells (CTCs) from whole blood is an important capability for both clinical medicine and biological research. Current techniques to perform this task place the isolated cells under excessive stresses that reduce cell viability, and potentially induce phenotype change, therefore losing valuable information about the isolated cells. We present a biodegradable nano-film coating on the surface of a microfluidic chip, which can be used to effectively capture as well as non-invasively release cancer cell lines such as PC-3, LNCaP, DU 145, H1650 and H1975. We have applied layer-by-layer (LbL) assembly to create a library of ultrathin coatings using a broad range of materials through complementary interactions. By developing an LbL nano-film coating with an affinity-based cell-capture surface that is capable of selectively isolating cancer cells from whole blood, and that can be rapidly degraded on command, we are able to gently isolate cancer cells and recover them without compromising cell viability or proliferative potential. Our approach has the capability to overcome practical hurdles and provide viable cancer cells for downstream analyses, such as live cell imaging, single cell genomics, and in vitro cell culture of recovered cells. Furthermore, CTCs from cancer patients were also captured, identified, and successfully released using the LbL-modified microchips. PMID:26142780

  6. Protein interacting with C kinase 1 suppresses invasion and anchorage-independent growth of astrocytic tumor cells

    PubMed Central

    Cockbill, Louisa M. R.; Murk, Kai; Love, Seth; Hanley, Jonathan G.

    2015-01-01

    Astrocytic tumors are the most common form of primary brain tumor. Astrocytic tumor cells infiltrate the surrounding CNS tissue, allowing them to evade removal upon surgical resection of the primary tumor. Dynamic changes to the actin cytoskeleton are crucial to cancer cell invasion, but the specific mechanisms that underlie the particularly invasive phenotype of astrocytic tumor cells are unclear. Protein interacting with C kinase 1 (PICK1) is a PDZ and BAR domain–containing protein that inhibits actin-related protein 2/3 (Arp2/3)-dependent actin polymerization and is involved in regulating the trafficking of a number of cell-surface receptors. Here we report that, in contrast to other cancers, PICK1 expression is down-regulated in grade IV astrocytic tumor cell lines and also in clinical cases of the disease in which grade IV tumors have progressed from lower-grade tumors. Exogenous expression of PICK1 in the grade IV astrocytic cell line U251 reduces their capacity for anchorage-independent growth, two-dimensional migration, and invasion through a three-dimensional matrix, strongly suggesting that low PICK1 expression plays an important role in astrocytic tumorigenesis. We propose that PICK1 negatively regulates neoplastic infiltration of astrocytic tumors and that manipulation of PICK1 is an attractive possibility for therapeutic intervention. PMID:26466675

  7. Recombinant disintegrin domain of human ADAM9 inhibits migration and invasion of DU145 prostate tumor cells

    PubMed Central

    Martin, Ana Carolina Baptista Moreno; Cardoso, Ana Carolina Ferreira; Selistre-de-Araujo, Heloisa Sobreiro; Cominetti, Márcia Regina

    2015-01-01

    One of the most important features of malignant cells is their capacity to invade adjacent tissues and metastasize to distant organs. This process involves the creation, by tumor and stroma cells, of a specific microenvironment, suitable for proliferation, migration and invasion of tumor cells. The ADAM family of proteins has been involved in these processes. This work aimed to investigate the role of the recombinant disintegrin domain of the human ADAM9 (rADAM9D) on the adhesive and mobility properties of DU145 prostate tumor cells. rADAM9D was able to support DU145 cell adhesion, inhibit the migration of DU145 cells, as well as the invasion of this cell line through matrigel in vitro. Overall this work demonstrates that rADAM9D induces specific cellular migratory properties when compared with different constructs having additional domains, specially those of metalloproteinase and cysteine-rich domains. Furthermore, we showed that rADAM9D was able to inhibit cell adhesion, migration and invasion mainly through interacting with α6β1 in DU145 tumor cell line. These results may contribute to the development of new therapeutic strategies for prostate cancer. PMID:26211476

  8. Angiostatin directly inhibits human prostate tumor cell invasion by blocking plasminogen binding to its cellular receptor, CD26

    SciTech Connect

    Gonzalez-Gronow, Mario . E-mail: gonza002@mc.duke.edu; Grenett, Hernan E.; Gawdi, Govind; Pizzo, Salvatore V.

    2005-02-01

    Previous studies demonstrate that one of the six plasminogen type 2 glycoforms, plasminogen 2{epsilon}, enhances invasiveness of the 1-LN human prostate tumor cell line in an in vitro model. Binding of plasminogen 2{epsilon} to CD26 on the cell surface induces a Ca{sup 2+} signaling cascade which stimulates the expression of matrix metalloproteinase-9, required by these cells to invade Matrigel registered . We now report that angiostatin, a fragment derived from plasminogen which prevents endothelial cell proliferation, is also a potent, direct inhibitor of 1-LN tumor cell invasiveness. We studied the effect of individual plasminogen 2 glycoform-derived angiostatins and found that only angiostatin 2{epsilon} binds to CD26 on the surface of 1-LN cells at a site also recognized by plasminogen 2{epsilon}. As a result, the plasminogen 2{epsilon}-induced Ca{sup 2+} signaling cascade is inhibited, the expression of matrix metalloproteinase-9 is suppressed, and invasion of Matrigel registered by 1-LN cells is blocked. Angiostatin 2{epsilon} is also the only angiostatin glycoform which is able to inhibit in vitro endothelial cell proliferation and tubule formation. These studies suggest that, in addition to its ability to inhibit tumor vascularization, angiostatin 2{epsilon} may also directly block tumor metastasis.

  9. Misregulation of Stromelysin-1 in Mouse Mammary Tumor Cells Accompanies Acquisition of Stromelysin-1 dependent Invasive Properties

    SciTech Connect

    Lochter, A.; Srebrow, A.; Sympson, C.J.; Terracio, N.; Werb, Z.; Bissell, M.J.

    1997-02-21

    Stromelysin-1 is a member of the metalloproteinase family of extracellular matrix-degrading enzymes that regulates tissue remodeling. We previously established a transgenic mouse model in which rat stromelysin-1 targeted to the mammary gland augmented expression of endogenous stromelysin-1, disrupted functional differentiation, and induced mammary tumors. A cell line generated from an adenocarcinoma in one of these animals and a previously described mammary tumor cell line generated in culture readily invaded both a reconstituted basement membrane and type I collagen gels, whereas a nonmalignant, functionally normal epithelial cell line did not. Invasion of Matrigel by tumor cells was largely abolished by metalloproteinase inhibitors, but not by inhibitors of other proteinase families. Inhibition experiments with antisense oligodeoxynucleotides revealed that Matrigel invasion of both cell lines was critically dependent on stromelysin-1 expression. Invasion of collagen, on the other hand, was reduced by only 40-50%. Stromelysin-1 was expressed in both malignant and nonmalignant cells grown on plastic substrata. Its expression was completely inhibited in nonmalignant cells, but up-regulated in tumor cells, in response to Matrigel. Thus misregulation of stromelysin-1 expression appears to be an important aspect of mammary tumor cell progression to an invasive phenotype. The matrix metalloproteinases (MMPs) are a family of extracellular matrix (ECM)-degrading enzymes that have been implicated in a variety of normal developmental and pathological processes, including tumorigenesis. The MMP family comprises at least 15 members with different, albeit overlapping, substrate specificities. During activation of latent MMPs, their propeptides are cleaved and they are converted to a lower molecular weight form by other enzymes, including serine proteinases, and by autocatalytic cleavage. Among the MMPs, stromelysin-1 (SL1) possesses the broadest substrate specificity. Despite

  10. ROCK- and myosin-dependent matrix deformation enables protease-independent tumor-cell invasion in vivo.

    PubMed

    Wyckoff, Jeffrey B; Pinner, Sophie E; Gschmeissner, Steve; Condeelis, John S; Sahai, Erik

    2006-08-01

    Tumor cells invading three-dimensional matrices need to remodel the extracellular matrix (ECM) in their path. Many studies have focused on the role of extracellular proteases; however, cells with amoeboid or rounded morphologies are able to invade even when these enzymes are inhibited. Here, we describe the mechanism by which cells move through a dense ECM without proteolysis. Amoeboid tumor cells generate sufficient actomyosin force to deform collagen fibers and are able to push through the ECM. Force generation is elevated in metastatic MTLn3E cells, and this correlates with increased invasion and altered myosin light chain (MLC) organization. In metastatic cells, MLC is organized perpendicularly to the direction of movement behind the invading edge. Both the organization of MLC and force generation are dependent upon ROCK function. We demonstrate that ROCK regulates the phosphorylation of MLC just behind the invading margin of the cell. Imaging of live tumors shows that MLC is organized in a similar ROCK-dependent fashion in vivo and that inhibition of ROCK but not matrix-metalloproteases reduces cancer cell motility in vivo.

  11. Isoginkgetin inhibits tumor cell invasion by regulating phosphatidylinositol 3-kinase/Akt-dependent matrix metalloproteinase-9 expression.

    PubMed

    Yoon, Sang-Oh; Shin, Sejeong; Lee, Ho-Jae; Chun, Hyo-Kon; Chung, An-Sik

    2006-11-01

    Matrix metalloproteinase (MMP)-9 plays a key role in tumor invasion. Inhibitors of MMP-9 were screened from Metasequoia glyptostroboides (Dawn redwood) and one potent inhibitor, isoginkgetin, a biflavonoid, was identified. Noncytotoxic levels of isoginkgetin decreased MMP-9 production profoundly, but up-regulated the level of tissue inhibitor of metalloproteinase (TIMP)-1, an inhibitor of MMP-9, in HT1080 human fibrosarcoma cells. The major mechanism of Ras-dependent MMP-9 production in HT1080 cells was phosphatidylinositol 3-kinase (PI3K)/Akt/nuclear factor-kappaB (NF-kappaB) activation. Expression of dominant-active H-Ras and p85 (a subunit of PI3K) increased MMP-9 activity, whereas dominant-negative forms of these molecules decreased the level of MMP-9. H-Ras did not increase MMP-9 in the presence of a PI3K inhibitor, LY294002, and a NF-kappaB inhibitor, SN50. Further studies showed that isoginkgetin regulated MMP-9 production via PI3K/Akt/NF-kappaB pathway, as evidenced by the findings that isoginkgetin inhibited activities of both Akt and NF-kappaB. PI3K/Akt is a well-known key pathway for cell invasion, and isoginkgetin inhibited HT1080 tumor cell invasion substantially. Isoginkgetin was also quite effective in inhibiting the activities of Akt and MMP-9 in MDA-MB-231 breast carcinomas and B16F10 melanoma. Moreover, isoginkgetin treatment resulted in marked decrease in invasion of these cells. In summary, PI3K/Akt is a major pathway for MMP-9 expression and isoginkgetin markedly decreased MMP-9 expression and invasion through inhibition of this pathway. This suggests that isoginkgetin could be a potential candidate as a therapeutic agent against tumor invasion.

  12. The effect of fibrillar matrix architecture on tumor cell invasion of physically challenging environments.

    PubMed

    Guzman, Asja; Ziperstein, Michelle J; Kaufman, Laura J

    2014-08-01

    Local invasion by and dissemination of cancer cells from a primary tumor are key initial steps of metastasis, the most lethal aspect of cancer. To study these processes in vitro, the invasion of cells from multicellular breast cancer aggregates embedded in three-dimensional (3D) extracellular matrix culture systems was studied. This work showed that in 3D fibrillar environments composed of collagen I, pore size--not the viscoelastic properties of the matrix--was the biophysical characteristic controlling breast cancer cell invasion efficiency. Furthermore, it was shown that fibrillar matrix architecture is a crucial factor that allows for efficient 3D invasion. In a 3D non-fibrillar environment composed of basement membrane extract (BME), invasion efficiency was greatly diminished, the mesenchymal individual mode of 3D invasion was abolished, and establishment of cell polarity and protrusions was compromised. These effects were seen even though the BME matrix has invasion permissive viscoelasticity and suitable adhesion ligands. The altered and limited invasive behavior observed in BME was rescued through introduction of fibrillar collagen into the non-fibrillar matrix. The biophysical cues of fibrillar collagen facilitated efficient invasion of sterically disadvantageous environments through assisting cell polarization and formation of stable cell protrusions. Finally, we suggest the composite matrices employed in this study consisting of fibrillar collagen I and BME in either a liquid-like or gelled state are suitable for a wide range of 3D cell studies, as these matrices combine fibrillar features that require cells to deploy integrin-dependent mechanotransduction machinery and a tunable non-fibrillar component that may require cells to adopt alternative migratory modes.

  13. MicroRNA-588 suppresses tumor cell migration and invasion by targeting GRN in lung squamous cell carcinoma

    PubMed Central

    Qian, Li; Lin, Longlong; Du, Yufeng; Hao, Xiaoyan; Zhao, Yuze; Liu, Xuejun

    2016-01-01

    MicroRNAs (miRNAs) have been demonstrated to be critical in regulating tumor development and progression. The present study investigated the expression of miR-588 using reverse transcription-quantitative polymerase chain reaction analysis in 85 cases of lung squamous cell carcinoma (SCC), and observed the correlation between the expression of miR-588 with clinical pathologic features. The results indicated that the expression of miR-588 was predominantly lower in the tumor samples, compared with non-tumorous samples, and was negatively associated with tumor stages and lymph node invasion. The present study also examined the significance of the expression of miR-588 in SCC using gain- and loss-of-function analyses. It was found that miR-588 inhibited tumor cell migration and invasion. In addition, it was revealed that the overexpression of miR-588 in SCC cells reduced the mRNA and protein levels of progranulin (GRN), whereas miR-588 silencing increased the expression of GRN. A luciferase activity assay showed that miR-588 was able to directly bind to the 3′untranslated region of GRN and regulate its expression. Furthermore, it was found that the expression of GRN was inversely correlated with the expression of miR-588 in 85 paired SCC samples. These results indicated that GRN was involved in the miR-588-mediated suppressive functions in the progression of SCC. PMID:27571908

  14. Co-Crystal Structures of Inhibitors with MRCKβ, a Key Regulator of Tumor Cell Invasion

    PubMed Central

    Heikkila, Timo; Wheatley, Edward; Crighton, Diane; Schroder, Ewald; Boakes, Alexandra; Kaye, Sarah J.; Mezna, Mokdad; Pang, Leon; Rushbrooke, Mathew; Turnbull, Andrew; Olson, Michael F.

    2011-01-01

    MRCKα and MRCKβ (myotonic dystrophy kinase-related Cdc42-binding kinases) belong to a subfamily of Rho GTPase activated serine/threonine kinases within the AGC-family that regulate the actomyosin cytoskeleton. Reflecting their roles in myosin light chain (MLC) phosphorylation, MRCKα and MRCKβ influence cell shape and motility. We report further evidence for MRCKα and MRCKβ contributions to the invasion of cancer cells in 3-dimensional matrix invasion assays. In particular, our results indicate that the combined inhibition of MRCKα and MRCKβ together with inhibition of ROCK kinases results in significantly greater effects on reducing cancer cell invasion than blocking either MRCK or ROCK kinases alone. To probe the kinase ligand pocket, we screened 159 kinase inhibitors in an in vitro MRCKβ kinase assay and found 11 compounds that inhibited enzyme activity >80% at 3 µM. Further analysis of three hits, Y-27632, Fasudil and TPCA-1, revealed low micromolar IC50 values for MRCKα and MRCKβ. We also describe the crystal structure of MRCKβ in complex with inhibitors Fasudil and TPCA-1 bound to the active site of the kinase. These high-resolution structures reveal a highly conserved AGC kinase fold in a typical dimeric arrangement. The kinase domain is in an active conformation with a fully-ordered and correctly positioned αC helix and catalytic residues in a conformation competent for catalysis. Together, these results provide further validation for MRCK involvement in regulation of cancer cell invasion and present a valuable starting point for future structure-based drug discovery efforts. PMID:21949762

  15. Nestin regulates proliferation and invasion of gastrointestinal stromal tumor cells by altering mitochondrial dynamics.

    PubMed

    Wang, J; Cai, J; Huang, Y; Ke, Q; Wu, B; Wang, S; Han, X; Wang, T; Wang, Y; Li, W; Lao, C; Song, W; Xiang, A P

    2016-06-16

    Nestin is widely expressed in numerous tumors and has become a diagnostic and prognostic indicator. However, the exact mechanism by which nestin contributes to tumor malignancy remains poorly understood. Here, we found marked upregulation of nestin expression in highly proliferative and invasive gastrointestinal stromal tumor (GIST) specimens. Nestin knockdown in GIST cells reduced the proliferative and invasive activity owing to a decrease of mitochondrial intracellular reactive oxygen species (ROS) generation. Furthermore, nestin was co-localized with mitochondria, and knockdown of nestin increased mitochondrial elongation and influenced the mitochondrial function, including oxygen consumption rates, ATP generation and mitochondrial membrane potential and so on. In exploring the underlying mechanism, we demonstrated nestin knockdown inhibited the mitochondrial recruitment of Dynamin-related protein1 and induced the change of mitochondrial dynamics. Thus, nestin may have an important role in GIST malignancy by regulating mitochondrial dynamics and altering intracellular ROS levels. The findings provide new clues to reveal mechanisms by which nestin mediates the proliferation and invasion of GISTs.

  16. Inhibition of arachidonic acid metabolism decreases tumor cell invasion and matrix metalloproteinase expression.

    PubMed

    Koontongkaew, Sittichai; Monthanapisut, Paopanga; Saensuk, Theeranuch

    2010-11-01

    Head and neck cancers are known to synthesize arachidonic acid metabolites. Interfering with arachidonic acid metabolism may inhibit growth and invasiveness of cancer cells. In this study we investigate effects of sulindac (the non-selective COX inhibitor), aspirin (the irreversible, preferential COX-1 inhibitor), NS-398 (the selective COX-2 inhibitor), NDGA (nordihydroguaiaretic acid, the selective LOX inhibitor) and ETYA (5,8,11,14-eicosatetraynoic acid, the COX and LOX inhibitor) on cell viability, MMP-2 and MMP-9 activities, and in vitro invasion of cancer cells derived from primary and metastatic head and neck, and colon cancers. The inhibitors of COX and/or LOX could inhibit cell proliferation, MMP activity and invasion in head and neck and colon cancer cells. However, the inhibitory effect was obviously observed in colon cancer cells. Inhibition of arachidonic acid metabolism caused a decrease in cancer cell motility, which partially explained by the inhibition of MMPs. Therefore, COX and LOX pathways play important roles in head and neck cancer cell growth. PMID:20654727

  17. Three-dimensional cell culture model for measuring the effects of interstitial fluid flow on tumor cell invasion.

    PubMed

    Tchafa, Alimatou M; Shah, Arpit D; Wang, Shafei; Duong, Melissa T; Shieh, Adrian C

    2012-07-25

    The growth and progression of most solid tumors depend on the initial transformation of the cancer cells and their response to stroma-associated signaling in the tumor microenvironment (1). Previously, research on the tumor microenvironment has focused primarily on tumor-stromal interactions (1-2). However, the tumor microenvironment also includes a variety of biophysical forces, whose effects remain poorly understood. These forces are biomechanical consequences of tumor growth that lead to changes in gene expression, cell division, differentiation and invasion(3). Matrix density (4), stiffness (5-6), and structure (6-7), interstitial fluid pressure (8), and interstitial fluid flow (8) are all altered during cancer progression. Interstitial fluid flow in particular is higher in tumors compared to normal tissues (8-10). The estimated interstitial fluid flow velocities were measured and found to be in the range of 0.1-3 μm s(-1), depending on tumor size and differentiation (9, 11). This is due to elevated interstitial fluid pressure caused by tumor-induced angiogenesis and increased vascular permeability (12). Interstitial fluid flow has been shown to increase invasion of cancer cells (13-14), vascular fibroblasts and smooth muscle cells (15). This invasion may be due to autologous chemotactic gradients created around cells in 3-D (16) or increased matrix metalloproteinase (MMP) expression (15), chemokine secretion and cell adhesion molecule expression (17). However, the mechanism by which cells sense fluid flow is not well understood. In addition to altering tumor cell behavior, interstitial fluid flow modulates the activity of other cells in the tumor microenvironment. It is associated with (a) driving differentiation of fibroblasts into tumor-promoting myofibroblasts (18), (b) transporting of antigens and other soluble factors to lymph nodes (19), and (c) modulating lymphatic endothelial cell morphogenesis (20). The technique presented here imposes interstitial

  18. LIMK Regulates Tumor-Cell Invasion and Matrix Degradation Through Tyrosine Phosphorylation of MT1-MMP

    PubMed Central

    Lagoutte, Emilie; Villeneuve, Clémentine; Lafanechère, Laurence; Wells, Claire M.; Jones, Gareth E.; Chavrier, Philippe; Rossé, Carine

    2016-01-01

    During their metastatic spread, cancer cells need to remodel the extracellular matrix in order to migrate through stromal compartments adjacent to the primary tumor. Dissemination of breast carcinoma cells is mediated by membrane type 1-matrix metalloproteinase (MT1-MMP/MMP14), the main invadopodial matrix degradative component. Here, we identify MT1-MMP as a novel interacting partner of dual-specificity LIM Kinase-1 and -2 (LIMK1/2), and provide several evidence for phosphorylation of tyrosine Y573 in the cytoplasmic domain of MT1-MMP by LIMK. Phosphorylation of Y573 influences association of F-actin binding protein cortactin to MT1-MMP-positive endosomes and invadopodia formation and matrix degradation. Moreover, we show that LIMK1 regulates cortactin association to MT1-MMP-positive endosomes, while LIMK2 controls invadopodia-associated cortactin. In turn, LIMK1 and LIMK2 are required for MT1-MMP-dependent matrix degradation and cell invasion in a three-dimensional type I collagen environment. This novel link between LIMK1/2 and MT1-MMP may have important consequences for therapeutic control of breast cancer cell invasion. PMID:27116935

  19. CD44-related chondroitin sulfate proteoglycan, a cell surface receptor implicated with tumor cell invasion, mediates endothelial cell migration on fibrinogen and invasion into a fibrin matrix.

    PubMed Central

    Henke, C A; Roongta, U; Mickelson, D J; Knutson, J R; McCarthy, J B

    1996-01-01

    Microvascular endothelial cell invasion into the fibrin provisional matrix is an integral component of angiogenesis during wound repair. Cell surface receptors which interact with extracellular matrix proteins participate in cell migration and invasion. Malignant cells use CD44-related chondroitin sulfate proteoglycan (CSPG) as a matrix receptor to mediate migration and invasion. In this study, we examine whether cell surface CSPG can mediate similar events in nonmalignant wound microvascular endothelial cells or whether use of CSPG for migration and invasion is a property largely restricted to malignant cells. After inhibiting CSPG synthesis with p-nitrophenyl beta-d xylopyranoside (beta-d xyloside), wound microvascular endothelial cells were capable of attaching and spreading on the surface of a fibrin gel; however, their ability to invade the fibrin matrix was virtually eliminated. To begin to examine the mechanism by which endothelial cells use CSPG to invade fibrin matrices, cell adhesion and migration on fibrinogen was examined. Endothelial cell adhesion and migration on fibrinogen were inhibited by both beta-d xyloside and after cleavage of chondroitin sulfate from the core protein by chondroitinase ABC. We have determined that wound microvascular endothelial cells express the majority of their proteoglycan as CSPG and that the CSPG core protein is immunologically related to CD44. PCR studies show that these cells express both the "standard" (CD44H) isoform and an isoform containing the variably spliced exon V3. In addition, anti-CD44 antibody blocks endothelial cell migration on fibrinogen. Affinity chromatography studies reveal that partially purified microvascular endothelial cell CSPG binds fibrinogen. These findings suggest that CD44-related CSPG, a molecule implicated in the invasive behavior of tumor cells, is capable of binding fibrinogen/fibrin, thereby mediating endothelial cell migration and invasion into the fibrin provisional matrix during wound

  20. BCAT1 promotes tumor cell migration and invasion in hepatocellular carcinoma

    PubMed Central

    Xu, Meng; Liu, Qingquan; Jia, Yuli; Tu, Kangsheng; Yao, Yingmin; Liu, Qingguang; Guo, Cheng

    2016-01-01

    Branched-chain amino acid transaminase 1 (BCAT1) has been associated with numerous types of tumors; however, few previous studies have evaluated the expression and role of BCAT1 in hepatocellular carcinoma (HCC). In the present study, the expression of BCAT1 was detected by reverse transcription-quantitative polymerase chain reaction and immunoblotting in six HCC cell lines and 74 pairs of HCC and adjacent non-cancerous liver tissues. In addition, the correlation between the expression levels of c-Myc and BCAT1 was analyzed using immunohistochemistry. Furthermore, RNA silencing was performed using c-Myc-specific or BCAT1-specific small interfering RNA, after which wound healing and Transwell cell invasion assays were performed. Finally, the clinicopathological characteristics of BCAT1 in patients with HCC were analyzed. It was shown that the expression of BCAT1 was significantly higher in HCC tissues compared with adjacent non-tumor tissues (P<0.001), and in HCC cell lines compared within the L-02 hepatic cell line (P<0.001). In addition, immunohistochemical analyses indicated that the expression of BCAT1 was positively correlated with c-Myc (r=0.706, P<0.001). BCAT1 expression was shown to be downregulated in c-Myc-knockdown cells, and silencing of BCAT1 expression reduced the invasion and migration of HCC cells. Furthermore, a clinical analysis indicated that BCAT1 expression in HCC tissues was significantly associated with the tumor-node-metastasis stage, tumor number and tumor differentiation (all P<0.05), and that BCAT1 was able to predict the 5-year survival and disease-free survival rates of patients with HCC (both P<0.001). The results of the present study suggested that BCAT1 expression is upregulated in patients with HCC, and that BCAT1 may serve as a potential molecular target for the diagnosis and treatment of HCC.

  1. Mammary Tumor-Associated RNAs Impact Tumor Cell Proliferation, Invasion, and Migration.

    PubMed

    Diermeier, Sarah D; Chang, Kung-Chi; Freier, Susan M; Song, Junyan; El Demerdash, Osama; Krasnitz, Alexander; Rigo, Frank; Bennett, C Frank; Spector, David L

    2016-09-27

    Long non-coding RNAs (lncRNAs) represent the largest and most diverse class of non-coding RNAs, comprising almost 16,000 currently annotated transcripts in human and 10,000 in mouse. Here, we investigated the role of lncRNAs in mammary tumors by performing RNA-seq on tumor sections and organoids derived from MMTV-PyMT and MMTV-Neu-NDL mice. We identified several hundred lncRNAs that were overexpressed compared to normal mammary epithelium. Among these potentially oncogenic lncRNAs we prioritized a subset as Mammary Tumor Associated RNAs (MaTARs) and determined their human counterparts, hMaTARs. To functionally validate the role of MaTARs, we performed antisense knockdown and observed reduced cell proliferation, invasion, and/or organoid branching in a cancer-specific context. Assessing the expression of hMaTARs in human breast tumors revealed that 19 hMaTARs are significantly upregulated and many of these correlate with breast cancer subtype and/or hormone receptor status, indicating potential clinical relevance. PMID:27681436

  2. Autocrine CSF1R signaling mediates switching between invasion and proliferation downstream of TGFβ in claudin-low breast tumor cells.

    PubMed

    Patsialou, A; Wang, Y; Pignatelli, J; Chen, X; Entenberg, D; Oktay, M; Condeelis, J S

    2015-05-21

    Patient data suggest that colony-stimulating factor-1 (CSF1) and its receptor (CSF1R) have critical roles during breast cancer progression. We have previously shown that in human breast tumors expressing both CSF1 and CSF1R, invasion in vivo is dependent both on a paracrine interaction with tumor-associated macrophages and an autocrine regulation of CSF1R in the tumor cells themselves. Although the role of the paracrine interaction between tumor cells and macrophages has been extensively studied, very little is known about the mechanism by which the autocrine CSF1R signaling contributes to tumor progression. We show here that breast cancer patients of the claudin-low subtype have significantly increased expression of CSF1R. Using a panel of breast cancer cell lines, we confirm that CSF1R expression is elevated and regulated by TGFβ specifically in claudin-low cell lines. Abrogation of autocrine CSF1R signaling in MDA-MB-231 xenografts (a claudin-low cell line) leads to increased tumor size by enhanced proliferation, but significantly reduced invasion, dissemination and metastasis. Indeed, we show that proliferation and invasion are oppositely regulated by CSF1R downstream of TGFβ only in claudin-low cell lines. Intravital multiphoton imaging revealed that inhibition of CSF1R in the tumor cells leads to decreased in vivo motility and a more cohesive morphology. We show that, both in vitro and in vivo, CSF1R inhibition results in a reversal of claudin-low marker expression by significant upregulation of luminal keratins and tight-junction proteins such as claudins. Finally, we show that artificial overexpression of claudins in MDA-MB-231 cells is sufficient to tip the cells from an invasive state to a proliferative state. Our results suggest that autocrine CSF1R signaling is essential in maintaining low claudin expression and that it mediates a switch between the proliferative and the invasive state in claudin-low tumor cells downstream of TGFβ.

  3. Tamoxifen inhibits tumor cell invasion and metastasis in mouse melanoma through suppression of PKC/MEK/ERK and PKC/PI3K/Akt pathways

    SciTech Connect

    Matsuoka, Hiroshi; Tsubaki, Masanobu; Yamazoe, Yuzuru; Ogaki, Mitsuhiko; Satou, Takao; Itoh, Tatsuki; Kusunoki, Takashi; Nishida, Shozo

    2009-07-15

    In melanoma, several signaling pathways are constitutively activated. Among these, the protein kinase C (PKC) signaling pathways are activated through multiple signal transduction molecules and appear to play major roles in melanoma progression. Recently, it has been reported that tamoxifen, an anti-estrogen reagent, inhibits PKC signaling in estrogen-negative and estrogen-independent cancer cell lines. Thus, we investigated whether tamoxifen inhibited tumor cell invasion and metastasis in mouse melanoma cell line B16BL6. Tamoxifen significantly inhibited lung metastasis, cell migration, and invasion at concentrations that did not show anti-proliferative effects on B16BL6 cells. Tamoxifen also inhibited the mRNA expressions and protein activities of matrix metalloproteinases (MMPs). Furthermore, tamoxifen suppressed phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and Akt through the inhibition of PKC{alpha} and PKC{delta} phosphorylation. However, other signal transduction factor, such as p38 mitogen-activated protein kinase (p38MAPK) was unaffected. The results indicate that tamoxifen suppresses the PKC/mitogen-activated protein kinase kinase (MEK)/ERK and PKC/phosphatidylinositol-3 kinase (PI3K)/Akt pathways, thereby inhibiting B16BL6 cell migration, invasion, and metastasis. Moreover, tamoxifen markedly inhibited not only developing but also clinically evident metastasis. These findings suggest that tamoxifen has potential clinical applications for the treatment of tumor cell metastasis.

  4. RNA interference-mediated targeting of DKK1 gene expression in Ishikawa endometrial carcinoma cells causes increased tumor cell invasion and migration

    PubMed Central

    YI, NUO; LIAO, QIN-PING; LI, ZHEN-HUA; XIE, BAO-JIANG; HU, YU-HONG; YI, WEI; LIU, MIN

    2013-01-01

    The Wnt signaling pathway plays an essential role in tumor invasion and migration. DKK1 functions as an important inhibitor of the pathway and represents a promising target for cancer therapy. The aim of the present study was to determine the role of DKK1 in endometrial carcinoma (EC) cell invasion and migration using RNA interference (RNAi) technology. Ishikawa EC cells were transfected at high efficiency with specific DKK1 siRNA. RT-PCR and western blot analysis were used to determine the mRNA and protein levels of DKK1, β-catenin and metalloproteinase 14 (MMP14) in siRNA-treated and -untreated cells. In addition, the invasion and migration of the EC cells were detected by invasion and migration assays. Transient transfection of DKK1 siRNA significantly inhibited the mRNA and protein levels of DKK1. Markedly increased cell invasion and migration was observed following treatment with DKK1 siRNA when compared with the negative control siRNA-treated and siRNA-untreated cells. The knockdown of DKK1 also elevated the mRNA and protein levels of β-catenin and MMP14 involved in the Wnt signaling pathway, indicating that targeting this gene may promote intracellular Wnt signal transduction and thus, accelerate EC cell invasion and migration in vitro. The RNAi-mediated targeting of DKK1 gene expression in Ishikawa EC cells resulted in increased tumor cell invasion and migration. DKK1 was identified as an inhibitor of EC cell invasion and migration via its novel role in the Wnt signaling pathway. Targeting DKK1 may therefore represent an effective anti-invasion and -migration strategy for the treatment of EC. PMID:24137406

  5. The NHERF1 PDZ2 Domain Regulates PKA–RhoA–p38-mediated NHE1 Activation and Invasion in Breast Tumor Cells

    PubMed Central

    Cardone, Rosa A.; Bellizzi, Antonia; Busco, Giovanni; Weinman, Edward J.; Dell'Aquila, Maria E.; Casavola, Valeria; Azzariti, Amalia; Mangia, Anita; Paradiso, Angelo

    2007-01-01

    Understanding the signal transduction systems governing invasion is fundamental for the design of therapeutic strategies against metastasis. Na+/H+ exchanger regulatory factor (NHERF1) is a postsynaptic density 95/disc-large/zona occludens (PDZ) domain-containing protein that recruits membrane receptors/transporters and cytoplasmic signaling proteins into functional complexes. NHERF1 expression is altered in breast cancer, but its effective role in mammary carcinogenesis remains undefined. We report here that NHERF1 overexpression in human breast tumor biopsies is associated with metastatic progression, poor prognosis, and hypoxia-inducible factor-1α expression. In cultured tumor cells, hypoxia and serum deprivation increase NHERF1 expression, promote the formation of leading-edge pseudopodia, and redistribute NHERF1 to these pseudopodia. This pseudopodial localization of NHERF1 was verified in breast biopsies and in three-dimensional Matrigel culture. Furthermore, serum deprivation and hypoxia stimulate the Na+/H+ exchanger, invasion, and activate a protein kinase A (PKA)-gated RhoA/p38 invasion signal module. Significantly, NHERF1 overexpression was sufficient to induce these morphological and functional changes, and it potentiated their induction by serum deprivation. Functional experiments with truncated and binding groove-mutated PDZ domain constructs demonstrated that NHERF1 regulates these processes through its PDZ2 domain. We conclude that NHERF1 overexpression enhances the invasive phenotype in breast cancer cells, both alone and in synergy with exposure to the tumor microenvironment, via the coordination of PKA-gated RhoA/p38 signaling. PMID:17332506

  6. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion.

    PubMed

    Zhou, Pengcheng; Erfani, Sonia; Liu, Zeyi; Jia, Changhe; Chen, Yecang; Xu, Bingwei; Deng, Xinyu; Alfáro, Jose E; Chen, Li; Napier, Dana; Lu, Michael; Huang, Jian-An; Liu, Chunming; Thibault, Olivier; Segal, Rosalind; Zhou, Binhua P; Kyprianou, Natasha; Horbinski, Craig; Yang, Xiuwei H

    2015-10-01

    Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p < 0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma. PMID:26377974

  7. CD151-α3β1 integrin complexes are prognostic markers of glioblastoma and cooperate with EGFR to drive tumor cell motility and invasion

    PubMed Central

    Xu, Bingwei; Deng, Xinyu; Alfáro, Jose E.; Chen, Li; Napier, Dana; Lu, Michael; Huang, Jian-An; Liu, Chunming; Thibault, Olivier; Segal, Rosalind; Zhou, Binhua P.; Kyprianou, Natasha; Horbinski, Craig; Yang, Xiuwei H.

    2015-01-01

    Glioblastoma, one of the most aggressive forms of brain cancer, is featured by high tumor cell motility and invasiveness, which not only fuel tumor infiltration, but also enable escape from surgical or other clinical interventions. Thus, better understanding of how these malignant traits are controlled will be key to the discovery of novel biomarkers and therapies against this deadly disease. Tetraspanin CD151 and its associated α3β1 integrin have been implicated in facilitating tumor progression across multiple cancer types. How these adhesion molecules are involved in the progression of glioblastoma, however, remains largely unclear. Here, we examined an in-house tissue microarray-based cohort of 96 patient biopsies and TCGA dataset to evaluate the clinical significance of CD151 and α3β1 integrin. Functional and signaling analyses were also conducted to understand how these molecules promote the aggressiveness of glioblastoma at molecular and cellular levels. Results from our analyses showed that CD151 and α3 integrin were significantly elevated in glioblastomas at both protein and mRNA levels, and exhibited strong inverse correlation with patient survival (p < 0.006). These adhesion molecules also formed tight protein complexes and synergized with EGF/EGFR to accelerate tumor cell motility and invasion. Furthermore, disruption of such complexes enhanced the survival of tumor-bearing mice in a xenograft model, and impaired activation of FAK and small GTPases. Also, knockdown- or pharmacological agent-based attenuation of EGFR, FAK or Graf (ARHGAP26)/small GTPase-mediated pathways markedly mitigated the aggressiveness of glioblastoma cells. Collectively, our findings provide clinical, molecular and cellular evidence of CD151-α3β1 integrin complexes as promising prognostic biomarkers and therapeutic targets for glioblastoma. PMID:26377974

  8. CCN5/WISP-2 expression in breast adenocarcinoma is associated with less frequent progression of the disease and suppresses the invasive phenotypes of tumor cells.

    PubMed

    Banerjee, Snigdha; Dhar, Gopal; Haque, Inamul; Kambhampati, Suman; Mehta, Smita; Sengupta, Krishanu; Tawfik, Ossama; Phillips, Teresa A; Banerjee, Sushanta K

    2008-09-15

    Although previous in vitro studies predicted that CCN5/WISP-2 may act as an anti-invasive gene in breast cancer, the distribution pattern of CCN5 in breast cancer samples is conflicting. Thus, we systematically investigated the CCN5 expression profile in noninvasive and invasive breast tumor samples and its functional relevance in breast cancer progression. The studies showed that CCN5 expression is biphasic, such that in normal samples CCN5 expression is undetectable, whereas its expression is markedly increased in noninvasive breast lesions, including atypical ductal hyperplasia and ductal carcinoma in situ. Further, CCN5 mRNA and protein levels are significantly reduced as the cancer progresses from a noninvasive to invasive type. Additionally, we showed that CCN5 mRNA and protein level was almost undetectable in poorly differentiated cancers compared with the moderately or well-differentiated samples and its expression inversely correlated with lymph node positivity. The result was further supported by evaluating the RNA expression profile in microdissected sections using real-time PCR analysis. Therefore, our data suggest a protective function of CCN5 in noninvasive breast tumor cells. This hypothesis was further supported by our in vitro studies illuminating that CCN5 is a negative regulator of migration and invasion of breast cancer cells, and these events could be regulated by CCN5 through the modulation of the expression of genes essential for an invasive front. These include Snail-E-cadherin signaling and matrix metalloproteinase (MMP)-9 and MMP-2. Collectively, these studies suggest that the protective effect of CCN5 in breast cancer progression may have important therapeutic implications.

  9. XR5967, a novel modulator of plasminogen activator inhibitor-1 activity, suppresses tumor cell invasion and angiogenesis in vitro.

    PubMed

    Brooks, Teresa D; Wang, Shouming W; Brünner, Nils; Charlton, Peter A

    2004-01-01

    Recent reports suggest that elevated levels of plasminogen activator inhibitor (PAI)-1 may contribute to tumor progression. We have recently shown that antibodies to PAI-1 block the invasive and migratory potential of human fibrosarcoma cells and suppress angiogenesis in vitro. Here we report the in vitro evaluation of a low-molecular-weight modulator of PAI-1, XR5967, on invasion, migration and angiogenesis. XR5967, a diketopiperazine, dose-dependently inhibited the activity of human and murine PAI-1, towards urokinase plasminogen activator (uPA), with IC50 values of 800 nM and 8.3 microM, respectively. This was confirmed by SDS-PAGE, revealing that XR5967 inhibited complex formation between PAI-1 and uPA. This suppression may be caused by XR5967 promoting insertion of the reactive center loop within PAI-1. XR5967 dose-dependently inhibited the invasion of human HT1080 fibrosarcoma cells through Matrigel. Their invasion was reduced by 57% (p<0.001) at 5 microM. HT1080 cell migration was inhibited in a similar manner, indicating that PAI-1 may play an additional role in invasion, which is distinct to its role in the regulation of proteolysis. The potential of XR5967 to inhibit the invasion/migration of human endothelial cells was investigated in an in vitro model of angiogenesis. In this model XR5967 reduced tubule formation by 77% at 5 microM (p<0.001), highlighting a crucial role for PAI-1 in angiogenesis. These data stress the importance of a balanced proteolysis in the processes of invasion, migration and angiogenesis. Our results support the clinical findings and indicate that modulation of PAI-1 activity, with low-molecular-weight inhibitor of PAI-1 activity, may be of therapeutic benefit for the treatment of cancer.

  10. miR-940 Suppresses Tumor Cell Invasion and Migration via Regulation of CXCR2 in Hepatocellular Carcinoma

    PubMed Central

    Ding, Dong; Zhang, Yaodong; Yang, Renjie; Wang, Xing; Ji, Guwei; Huo, Liqun; Shao, Zicheng

    2016-01-01

    Aim. To investigate the expression of miR-940 in the hepatocellular carcinoma (HCC) and its impact on function and biological mechanism in the HCC cells. Methods. Quantitative RT-PCR analysis was used to quantify miR-940 expression in 46 cases of tissues and cells. Transfection of HCC cell lines was performed by miR-940 mimics; the abilities of invasion and migration were assessed through Transwell array. Western blot represents the alteration in expression of CXCR2 by miR-940 mimics. Results. miR-940 expression was decreased significantly in the HCC tissues and the relevant cell lines. miR-940 upregulation suppressed the invasion and migration of HCC cells in vitro. Furthermore, the CXCR2 was downregulated to suppress invasion and migration after miR-940 mimics. Moreover, decreased miR-940 expression was negatively correlated with Edmondson grade (P = 0.008), tumor microsatellite or multiple tumors (P = 0.04), vascular invasion (P = 0.035), and recurrence and metastasis (P = 0.038). Kaplan-Meier analysis demonstrated that decreased miR-940 expression contributed to poor overall survival (P < 0.05). Conclusions. Our findings present that miR-940 acts as a pivotal adaptor of CXCR2 and its transcription downregulated CXCR2 expression to decrease HCC invasion and migration in vitro. Our study suggests that miR-940 may be a novel poor prognostic biomarker for HCC. PMID:27807540

  11. Metastasis-associated Protein 1 Drives Tumor Cell Migration and Invasion through Transcriptional Repression of RING Finger Protein 144A*

    PubMed Central

    Marzook, Hezlin; Li, Da-Qiang; Nair, Vasudha S.; Mudvari, Prakriti; Reddy, Sirigiri Divijendra Natha; Pakala, Suresh B.; Santhoshkumar, T. R.; Pillai, M. Radhakrishna; Kumar, Rakesh

    2012-01-01

    Metastasis-associated protein 1 (MTA1), a component of the nucleosome-remodeling and histone deacetylase complex, is widely up-regulated in human cancers and significantly correlated with tumor invasion and metastasis, but the mechanisms involved remain largely unknown. Here, we report that MTA1 transcriptionally represses the expression of RING finger protein 144A (RNF144A), an uncharacterized gene whose protein product possesses potential E3 ubiquitin ligase activity, by recruiting the histone deacetylase 2 (HDAC2) and CCAAT/enhancer-binding protein α (c/EBPα) co-repressor complex onto human RNF144A promoter. Furthermore, an inverse correlation between the expression levels of MTA1 and RNF144A was demonstrated in publicly available breast cancer microarray datasets and the MCF10 breast cancer progression model system. To address functional aspects of MTA1 regulation of RNF144A, we demonstrate that RNF144A is a novel suppressor of cancer migration and invasion, two requisite steps of metastasis in vivo, and knockdown of endogenous RNF144A by small interfering RNAs accelerates the migration and invasion of MTA1-overexpressing cells. These results suggest that RNF144A is partially responsible for MTA1-mediated migration and invasion and that MTA1 overexpression in highly metastatic cancer cells drives cell migration and invasion by, at least in part, interfering with the suppressive function of RNF144A through transcriptional repression of RNF144A expression. Together, these findings provide novel mechanistic insights into regulation of tumor progression and metastasis by MTA1 and highlight a previously unrecognized role of RNF144A in MTA1-driven cancer cell migration and invasion. PMID:22184113

  12. Does polyploidy facilitate long-distance dispersal?

    PubMed Central

    Linder, H. Peter; Barker, Nigel P.

    2014-01-01

    Background and Aims The ability of plant lineages to reach all continents contributes substantially to their evolutionary success. This is exemplified by the Poaceae, one of the most successful angiosperm families, in which most higher taxa (tribes, subfamilies) have global distributions. Due to the old age of the ocean basins relative to the major angiosperm radiations, this is only possible by means of long-distance dispersal (LDD), yet the attributes of lineages with successful LDD remain obscure. Polyploid species are over-represented in invasive floras and in the previously glaciated Arctic regions, and often have wider ecological tolerances than diploids; thus polyploidy is a candidate attribute of successful LDD. Methods The link between polyploidy and LDD was explored in the globally distributed grass subfamily Danthonioideae. An almost completely sampled and well-resolved species-level phylogeny of the danthonioids was used, and the available cytological information was assembled. The cytological evolution in the clade was inferred using maximum likelihood (ML) as implemented in ChromEvol. The biogeographical evolution in the clade was reconstructed using ML and Bayesian approaches. Key Results Numerous increases in ploidy level are demonstrated. A Late Miocene–Pliocene cycle of polyploidy is associated with LDD, and in two cases (the Australian Rytidosperma and the American Danthonia) led to secondary polyploidy. While it is demonstrated that successful LDD is more likely in polyploid than in diploid lineages, a link between polyploidization events and LDD is not demonstrated. Conclusions The results suggest that polyploids are more successful at LDD than diploids, and that the frequent polyploidy in the grasses might have facilitated the extensive dispersal among continents in the family, thus contributing to their evolutionary success. PMID:24694830

  13. Manganese superoxide dismutase promotes interaction of actin, S100A4 and Talin, and enhances rat gastric tumor cell invasion

    PubMed Central

    Indo, Hiroko P.; Matsui, Hirofumi; Chen, Jing; Zhu, Haining; Hawkins, Clare L.; Davies, Michael J.; Yarana, Chontida; St. Clair, Daret K.; Majima, Hideyuki J.

    2015-01-01

    It has been demonstrated that cancer cells are under high levels of oxidative stress and express high levels of Manganese superoxide dismutase (MnSOD) to protect themselves and support the anabolic metabolism needed for growth and cell motility. The aim of this study was to identify proteins that may have a correlation with invasion and redox regulation by mitochondrial reactive oxygen species (ROS). MnSOD scavenges superoxide anions generated from mitochondria and is an important regulator of cellular redox status. Oxidative posttranslational modification of cysteine residues is a key mechanism that regulates protein structure and function. We hypothesized that MnSOD regulates intracellular reduced thiol status and promotes cancer invasion. A proteomic thiol-labeling approach with 5-iodoacetamidofluorescein was used to identify changes in intracellular reduced thiol-containing proteins. Our results demonstrate that overexpression of MnSOD maintained the major structural protein, actin, in a reduced state, and enhanced the invasion ability in gastric mucosal cancer cells, RGK1. We also found that the expression of Talin and S100A4 were increased in MnSOD-overexpressed RGK1 cells. Moreover, Talin bound not only with actin but also with S100A4, suggesting that the interaction of these proteins may, in part, contribute to the invasive ability of rat gastric cancer. PMID:26236095

  14. miR-129 suppresses tumor cell growth and invasion by targeting PAK5 in hepatocellular carcinoma

    SciTech Connect

    Zhai, Jian; Qu, Shuping; Li, Xiaowei; Zhong, Jiaming; Chen, Xiaoxia; Qu, Zengqiang; Wu, Dong

    2015-08-14

    Emerging evidence suggests that microRNAs (miRNAs) play important roles in regulating HCC development and progression; however, the mechanisms by which their specific functions and mechanisms remained to be further explored. miR-129 has been reported in gastric cancers, lung cancer and colon cancer. In this study, we disclosed a new tumor suppresser function of miR-129 in HCC. We also found the downregulation of miR-129 occurred in nearly 3/4 of the tumors examined (56/76) compared with adjacent nontumorous tissues, which was more importantly, correlated to the advanced stage and vascular invasion. We then demonstrated that miR-129 overexpression attenuated HCC cells proliferation and invasion, inducing apoptosis in vitro. Moreover, we used miR-129 antagonist and found that anti-miR-129 promoted HCC cells malignant phenotypes. Mechanistically, our further investigations revealed that miR-129 suppressed cell proliferation and invasion by targeting the 3’-untranslated region of PAK5, as well as miR-129 silencing up-regulated PAK5 expression. Moreover, miR-129 expression was inversely correlated with PAK5 expression in 76 cases of HCC samples. RNA interference of PAK5 attenuated anti-miR-129 mediated cell proliferation and invasion in HCC cells. Taken together, these results demonstrated that miR-129 suppressed tumorigenesis and progression by directly targeting PAK5, defining miR-129 as a potential treatment target for HCC. - Highlights: • Decreased of miR-129 is found in HCC and associated with advanced stage and metastasis. • miR-129 suppresses proliferation and invasion of HCC cells. • miR-129 directly targets the 3′ UTR of PAK5 and diminishes PAK5 expression. • PAK5 is involved in miR-129 mediated suppression functions.

  15. Development of a specific affinity-matured exosite inhibitor to MT1-MMP that efficiently inhibits tumor cell invasion in vitro and metastasis in vivo

    PubMed Central

    Botkjaer, Kenneth A.; Kwok, Hang Fai; Terp, Mikkel G.; Karatt-Vellatt, Aneesh; Santamaria, Salvatore; McCafferty, John; Andreasen, Peter A.; Itoh, Yoshifumi; Ditzel, Henrik J.; Murphy, Gillian

    2016-01-01

    The membrane-associated matrix metalloproteinase-14, MT1-MMP, has been implicated in pericellular proteolysis with an important role in cellular invasion of collagenous tissues. It is substantially upregulated in various cancers and rheumatoid arthritis, and has been considered as a potential therapeutic target. Here, we report the identification of antibody fragments to MT1-MMP that potently and specifically inhibit its cell surface functions. Lead antibody clones displayed inhibitory activity towards pro-MMP-2 activation, collagen-film degradation and gelatin-film degradation, and were shown to bind to the MT1-MMP catalytic domain outside the active site cleft, inhibiting binding to triple helical collagen. Affinity maturation using CDR3 randomization created a second generation of antibody fragments with dissociation constants down to 0.11 nM, corresponding to an improved affinity of 332-fold with the ability to interfere with cell-surface MT1-MMP functions, displaying IC50 values down to 5 nM. Importantly, the new inhibitors were able to inhibit collagen invasion by tumor-cells in vitro and in vivo primary tumor growth and metastasis of MDA-MB-231 cells in a mouse orthotopic xenograft model. Herein is the first demonstration that an inhibitory antibody targeting sites outside the catalytic cleft of MT1-MMP can effectively abrogate its in vivo activity during tumorigenesis and metastasis. PMID:26934448

  16. E2F3 amplification and overexpression is associated with invasive tumor growth and rapid tumor cell proliferation in urinary bladder cancer.

    PubMed

    Oeggerli, Martin; Tomovska, Sanja; Schraml, Peter; Calvano-Forte, Daniele; Schafroth, Salome; Simon, Ronald; Gasser, Thomas; Mihatsch, Michael J; Sauter, Guido

    2004-07-22

    E2F3 is located in the 6p22 bladder amplicon and encodes a transcription factor important for cell cycle regulation and DNA replication. To further investigate the role of E2F3 in bladder cancer, a tissue microarray containing samples from 2317 bladder tumors was used for gene copy number and expression analysis by means of fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC). E2F3 amplification was strongly associated with invasive tumor phenotype and high tumor grade (P < 0.0001 each). None of 272 pTaG1/G2 tumors, but 35 of 311 pT1-4 carcinomas (11.3%), had E2F3 amplification. A high E2F3 expression level was associated with high grade, advanced stage, and E2F3 gene amplification (P < 0.0001 each). To evaluate whether E2F3 expression correlates with tumor proliferation, the Ki67 labeling index (LI) was analysed for each tumor. There was a strong association between a high Ki67 LI and E2F3 expression (P < 0.0001), which was independent of grade and stage. We conclude that E2F3 is frequently amplified and overexpressed in invasively growing bladder cancer (stage pT1-4). E2F3 expression appears to provide a growth advantage to tumor cells by activating cell proliferation in a subset of bladder tumors.

  17. Self-assembled HCV core virus-like particles targeted and inhibited tumor cell migration and invasion

    NASA Astrophysics Data System (ADS)

    Li, Xiang; Xu, Xuehe; Jin, Aihui; Jia, Qunying; Zhou, Huaibin; Kang, Shuai; Lou, Yongliang; Gao, Jimin; Lu, Jianxin

    2013-09-01

    We used a baculovirus expression system to express fusion proteins of HCV core, RGD (Arg-Gly-Asp) peptide, and IFN-α2a fragments in Sf9 cells. Western blotting and electron microscopy demonstrate that HCV core, peptides RGD, and IFN-α2a fusion proteins assemble into 30 to 40 nm nano-particles (virus-like particles, VLPs). Xenograft assays show that VLPs greatly reduced tumor volume and weight with regard to a nontreated xenograft. Migration and invasion results show that VLPs can inhibit the migration and invasion of the breast cancer cells MDA-MB231. This study will provide theoretical and experimental basis for the establishment of safe and effective tumor-targeted drug delivery systems and clinical application of VLPs carrying cell interacting cargo.

  18. MicroRNA-940 promotes tumor cell invasion and metastasis by downregulating ZNF24 in gastric cancer

    PubMed Central

    Zhang, Zhe; Zhang, Xiaowei; Chang, Jinjia; Wu, Zheng; Tang, Wenbo; Gan, Lu; Sun, Menghong; Li, Jin

    2015-01-01

    Growing evidence indicates that microRNA (miRNA) plays a vital role in progression and metastasis of gastric cancer (GC). However, the underlying mechanism of miRNA-mediated metastasis has not been fully understood. Recently, miRNA-940 (miR-940) was found to be overexpressed in GC, which correlated with malignant progression and poor survival. Mechanistically, we found that miR-940 promoted GC cell migration, invasion, and metastasis in vivo by directly and functionally repressing the expression of Zinc Finger Transcription Factor 24 (ZNF24). Importantly, upregulation of ZNF24 could re-inhibit miR-940-induced migration and invasion. Hence, we demonstrated the oncogenic role of miR-940 in GC, finding that miR-940 promoted GC progression by directly downregulating ZNF24 expression, and targeting miR-940 could serve as a novel strategy for future GC therapy. PMID:26317898

  19. Species interactions and plant polyploidy.

    PubMed

    Segraves, Kari A; Anneberg, Thomas J

    2016-07-01

    Polyploidy is a common mode of speciation that can have far-reaching consequences for plant ecology and evolution. Because polyploidy can induce an array of phenotypic changes, there can be cascading effects on interactions with other species. These interactions, in turn, can have reciprocal effects on polyploid plants, potentially impacting their establishment and persistence. Although there is a wealth of information on the genetic and phenotypic effects of polyploidy, the study of species interactions in polyploid plants remains a comparatively young field. Here we reviewed the available evidence for how polyploidy may impact many types of species interactions that range from mutualism to antagonism. Specifically, we focused on three main questions: (1) Does polyploidy directly cause the formation of novel interactions not experienced by diploids, or does it create an opportunity for natural selection to then form novel interactions? (2) Does polyploidy cause consistent, predictable changes in species interactions vs. the evolution of idiosyncratic differences? (3) Does polyploidy lead to greater evolvability in species interactions? From the scarce evidence available, we found that novel interactions are rare but that polyploidy can induce changes in pollinator, herbivore, and pathogen interactions. Although further tests are needed, it is likely that selection following whole-genome duplication is important in all types of species interaction and that there are circumstances in which polyploidy can enhance the evolvability of interactions with other species. PMID:27370313

  20. Long noncoding RNA-EBIC promotes tumor cell invasion by binding to EZH2 and repressing E-cadherin in cervical cancer.

    PubMed

    Sun, Ning-xia; Ye, Chen; Zhao, Qian; Zhang, Qing; Xu, Chen; Wang, Shao-bing; Jin, Zhi-jun; Sun, Shu-han; Wang, Fang; Li, Wen

    2014-01-01

    In recent years, long noncoding RNAs (lncRNAs) have been demonstrated to play key roles in tumorgenesis. However, the contributions of lncRNAs to cervical cancer (CC) remain largely unknown. In this study, differentially expressed lncRNAs and mRNAs in cervical cancer and paired peritumoral tissues were detected by transcriptome microarray analysis. We found 708 probe sets of lncRNAs increased and 836 probe sets decreased in CC tissues, while 1288 mRNA differential probe sets increased and 901 mRNA probe sets decreased. The results were validated by quantitative real-time polymerase chain reaction (qPCR). Then, we found a specific differentially expressed lncRNA can physically bind to enhancer of zeste homolog2 (EZH2) by using RNA immunoprecipitation. We termed it as EZH2-binding lncRNA in cervical cancer [lncRNA-EBIC]. Wound healing assays and Matrigel invasion assays were used to determine the function of this lncRNA by silencing it. We observed that the migration and invasion of cervical cancer cells in vitro were inhibited upon suppression of lncRNA-EBIC by siRNA. We also found that the association between lncRNA-EBIC and EZH2 was required for the repression of E-cadherin, which was a key molecular in the metastasis of cervical cancer. Conclusion: These results demonstrated that lncRNA-EBIC was an oncogenic lncRNA, which could promote tumor cell invasion in CC by binding to EZH2 and inhibiting E-cadherin expression.

  1. Long Noncoding RNA-EBIC Promotes Tumor Cell Invasion by Binding to EZH2 and Repressing E-Cadherin in Cervical Cancer

    PubMed Central

    Zhao, Qian; Zhang, Qing; Xu, Chen; Wang, Shao-bing; Jin, Zhi-jun; Sun, Shu-han; Wang, Fang; Li, Wen

    2014-01-01

    In recent years, long noncoding RNAs (lncRNAs) have been demonstrated to play key roles in tumorgenesis. However, the contributions of lncRNAs to cervical cancer (CC) remain largely unknown. In this study, differentially expressed lncRNAs and mRNAs in cervical cancer and paired peritumoral tissues were detected by transcriptome microarray analysis. We found 708 probe sets of lncRNAs increased and 836 probe sets decreased in CC tissues, while 1288 mRNA differential probe sets increased and 901 mRNA probe sets decreased. The results were validated by quantitative real-time polymerase chain reaction (qPCR). Then, we found a specific differentially expressed lncRNA can physically bind to enhancer of zeste homolog2 (EZH2) by using RNA immunoprecipitation. We termed it as EZH2-binding lncRNA in cervical cancer [lncRNA-EBIC]. Wound healing assays and Matrigel invasion assays were used to determine the function of this lncRNA by silencing it. We observed that the migration and invasion of cervical cancer cells in vitro were inhibited upon suppression of lncRNA-EBIC by siRNA. We also found that the association between lncRNA-EBIC and EZH2 was required for the repression of E-cadherin, which was a key molecular in the metastasis of cervical cancer. Conclusion These results demonstrated that lncRNA-EBIC was an oncogenic lncRNA, which could promote tumor cell invasion in CC by binding to EZH2 and inhibiting E-cadherin expression. PMID:25007342

  2. MicroRNA-126 inhibits tumor cell invasion and metastasis by downregulating ROCK1 in renal cell carcinoma

    PubMed Central

    ZHANG, GUI-MING; LUO, LEI; DING, XUE-MEI; DONG, DA-HAI; LI, BIN; MA, XIAO-CHENG; SUN, LI-JIANG

    2016-01-01

    MicroRNAs (miRNAs) are involved in cancer development and progression. Renal cell carcinoma (RCC) frequently undergoes metastasis and has a high mortality rate. The current study measured miRNA-126 (miR-126) expression levels in 128 pairs of clear cell RCC and adjacent normal kidney tissue samples by reverse transcription-quantitative polymerase chain reaction, and analyzed the association between miR-126 and various clinicopathological parameters. In addition, cell proliferation, wound healing and cell invasion assays were conducted using RCC cells overexpressing miR-126. Potential miR-126 target genes and the signaling pathways that may be regulated by miR-126 were then examined. miR-126 expression was significantly reduced in patients with metastatic RCC compared with patients without metastasis. Consistently, overexpression of miR-126 in RCC cells significantly inhibited cell proliferation, migration and invasion in vitro compared with negative control miRNA. A luciferase reporter assay demonstrated that miR-126 targets Rho associated coiled-coil containing protein kinase 1 (ROCK1) by directly binding the 3′-untranslated region. Furthermore, western blotting identified miR-126 as an important regulator of the AKT and extracellular signal-regulated 1/2 signaling pathways. The results of the present study indicate that miR-126 inhibits RCC cell proliferation, migration and invasion by downregulating ROCK1. These findings suggest that miR-126 may be valuable as a potential target for therapeutic intervention in RCC. PMID:27108693

  3. Acidic mucopolysaccharide from Holothuria leucospilota has antitumor effect by inhibiting angiogenesis and tumor cell invasion in vivo and in vitro.

    PubMed

    Zhang, Weiwei; Lu, Yin; Xu, Bo; Wu, Jiaming; Zhang, Lijuan; Gao, Ming; Zheng, Shizhong; Wang, Aiyun; Zhang, Changbin; Chen, Lei; Lei, Na

    2009-08-01

    Acidic mucopolysaccharide from Holothuria Leucospilota (HS) may affect some steps in metastasis cascade. In vitro, HS inhibited the growth of B16F10 cells and proliferation of VEGF-induced HUVEC dose-dependently compared to the control, VEGF-induced capillary-like tube networks and the numbers of migratory and invasive cells were significantly inhibited by HS in a dose-dependent manner under the cytotoxic doses. Additionally, VEGF-induced vessel sprouting of rat aortic ring was also inhibited by HS. It also has been demonstrated that the invasive ability of B16F10 melanoma cells through the Matrigel-embedded Boyden chamber was suppressed by 0.5 muM HS. The protein level secreted by B16F10 cells of MMP-2,-9 and VEGF were decreased by HS treatment. In vivo, a tumor growth inhibition study was carried out using mice bearing B16F10 cells model of metastasis, no matter experimental or spontaneous, showed that HS at 5.2, 11.6 and 26 mg/kg (weight of mice) could markedly decreased the metastatic tumors in mouse lung in a dose-dependent manner. In CAM assay and Matrigel plug assay in vivo, HS (50 microg/egg and 100 microg/egg) inhibited new blood vessel formation on the growing chick chorioallantoic membrane, and HS (5.2 and 26 mg/kg body weight) reduced the vessel density in Matrigel plugs implanted in mice. Taken together, these results demonstrate that HS has antimetastasic properties possibly via its antiangiogenesis induced by downregulation of VEGF and suppression of invasive ability of cancer cells mediated by downregulation of MMP-2, -9 and their activities.

  4. Regulation of survival, proliferation, invasion, angiogenesis, and metastasis of tumor cells through modulation of inflammatory pathways by nutraceuticals

    PubMed Central

    Gupta, Subash C.; Kim, Ji Hye; Prasad, Sahdeo

    2010-01-01

    Almost 25 centuries ago, Hippocrates, the father of medicine, proclaimed “Let food be thy medicine and medicine be thy food.” Exploring the association between diet and health continues today. For example, we now know that as many as 35% of all cancers can be prevented by dietary changes. Carcinogenesis is a multistep process involving the transformation, survival, proliferation, invasion, angiogenesis, and metastasis of the tumor and may take up to 30 years. The pathways associated with this process have been linked to chronic inflammation, a major mediator of tumor progression. The human body consists of about 13 trillion cells, almost all of which are turned over within 100 days, indicating that 70,000 cells undergo apoptosis every minute. Thus, apoptosis/cell death is a normal physiological process, and it is rare that a lack of apoptosis kills the patient. Almost 90% of all deaths due to cancer are linked to metastasis of the tumor. How our diet can prevent cancer is the focus of this review. Specifically, we will discuss how nutraceuticals, such as allicin, apigenin, berberine, butein, caffeic acid, capsaicin, catechin gallate, celastrol, curcumin, epigallocatechin gallate, fisetin, flavopiridol, gambogic acid, genistein, plumbagin, quercetin, resveratrol, sanguinarine, silibinin, sulforaphane, taxol, γ-tocotrienol, and zerumbone, derived from spices, legumes, fruits, nuts, and vegetables, can modulate inflammatory pathways and thus affect the survival, proliferation, invasion, angiogenesis, and metastasis of the tumor. Various cell signaling pathways that are modulated by these agents will also be discussed. PMID:20737283

  5. Tumor Cell Invasion Can Be Blocked by Modulators of Collagen Fibril Alignment That Control Assembly of the Extracellular Matrix.

    PubMed

    Grossman, Moran; Ben-Chetrit, Nir; Zhuravlev, Alina; Afik, Ran; Bassat, Elad; Solomonov, Inna; Yarden, Yosef; Sagi, Irit

    2016-07-15

    Abnormal architectures of collagen fibers in the extracellular matrix (ECM) are hallmarks of many invasive diseases, including cancer. Targeting specific stages of collagen assembly in vivo presents a great challenge due to the involvement of various crosslinking enzymes in the multistep, hierarchical process of ECM build-up. Using advanced microscopic tools, we monitored stages of fibrillary collagen assembly in a native fibroblast-derived 3D matrix system and identified anti-lysyl oxidase-like 2 (LOXL2) antibodies that alter the natural alignment and width of endogenic fibrillary collagens without affecting ECM composition. The disrupted collagen morphologies interfered with the adhesion and invasion properties of human breast cancer cells. Treatment of mice bearing breast cancer xenografts with the inhibitory antibodies resulted in disruption of the tumorigenic collagen superstructure and in reduction of primary tumor growth. Our approach could serve as a general methodology to identify novel therapeutics targeting fibrillary protein organization to treat ECM-associated pathologies. Cancer Res; 76(14); 4249-58. ©2016 AACR.

  6. Regulation of survival, proliferation, invasion, angiogenesis, and metastasis of tumor cells through modulation of inflammatory pathways by nutraceuticals.

    PubMed

    Gupta, Subash C; Kim, Ji Hye; Prasad, Sahdeo; Aggarwal, Bharat B

    2010-09-01

    Almost 25 centuries ago, Hippocrates, the father of medicine, proclaimed "Let food be thy medicine and medicine be thy food." Exploring the association between diet and health continues today. For example, we now know that as many as 35% of all cancers can be prevented by dietary changes. Carcinogenesis is a multistep process involving the transformation, survival, proliferation, invasion, angiogenesis, and metastasis of the tumor and may take up to 30 years. The pathways associated with this process have been linked to chronic inflammation, a major mediator of tumor progression. The human body consists of about 13 trillion cells, almost all of which are turned over within 100 days, indicating that 70,000 cells undergo apoptosis every minute. Thus, apoptosis/cell death is a normal physiological process, and it is rare that a lack of apoptosis kills the patient. Almost 90% of all deaths due to cancer are linked to metastasis of the tumor. How our diet can prevent cancer is the focus of this review. Specifically, we will discuss how nutraceuticals, such as allicin, apigenin, berberine, butein, caffeic acid, capsaicin, catechin gallate, celastrol, curcumin, epigallocatechin gallate, fisetin, flavopiridol, gambogic acid, genistein, plumbagin, quercetin, resveratrol, sanguinarine, silibinin, sulforaphane, taxol, gamma-tocotrienol, and zerumbone, derived from spices, legumes, fruits, nuts, and vegetables, can modulate inflammatory pathways and thus affect the survival, proliferation, invasion, angiogenesis, and metastasis of the tumor. Various cell signaling pathways that are modulated by these agents will also be discussed.

  7. Indacaterol inhibits tumor cell invasiveness and MMP-9 expression by suppressing IKK/NF-κB activation.

    PubMed

    Lee, Su Ui; Ahn, Kyung-Seop; Sung, Min Hee; Park, Ji-Won; Ryu, Hyung Won; Lee, Hyun-Jun; Hong, Sung-Tae; Oh, Sei-Ryang

    2014-08-01

    The β2 adrenergic receptor (ADRB2) is a G protein-coupled transmembrane receptor expressed in the human respiratory tract and widely recognized as a pharmacological target for treatments of asthma and chronic obstructive pulmonary disorder (COPD). Although a number of ADRB2 agonists have been developed for use in asthma therapy, indacaterol is the only ultra-long-acting inhaled β2-agonist (LABA) approved by the FDA for relieving the symptoms in COPD patients. The precise molecular mechanism underlying the pharmacological effect of indacaterol, however, remains unclear. Here, we show that β-arrestin-2 mediates the internalization of ADRB2 following indacaterol treatment. Moreover, we demonstrate that indacaterol significantly inhibits tumor necrosis factor-α (TNF-α)-induced NF-κB activity by reducing levels of both phosphorylated-IKK and -IκBα, thereby decreasing NF-κB nuclear translocation and the expression of MMP-9, an NF-κB target gene. Subsequently, we show that indacaterol significantly inhibits TNF-α/NF-κB-induced cell invasiveness and migration in a human cancer cell line. In conclusion, we propose that indacaterol may inhibit NF-κB activity in a β-arrestin2-dependent manner, preventing further lung damage and improving lung function in COPD patients.

  8. KDM1A promotes tumor cell invasion by silencing TIMP3 in non-small cell lung cancer cells

    PubMed Central

    Li, Wang; Yang, Yan; Tian, Ye; Wang, Xujun; Chen, Sujun; Yang, Yuxin; Huang, Tianhao; Zhao, Tian; Tang, Liang; Su, Bo; Li, Fei; Liu, X. Shirley; Zhang, Fan

    2016-01-01

    Epigenetic regulation plays an important role in tumor metastasis. KDM1A is a histone demethylase specific for H3K4me2/me1 demethylation, and has been found to be overexpressed in many cancers, including non-small cell lung cancer (NSCLC). However, the role of KDM1A in lung cancer remains unclear. Here, we show that KDM1A promotes cancer metastasis in NSCLC cells by repressing TIMP3 (tissue inhibitor of metalloproteinase 3) expression. Consistently with this, overexpression of TIMP3 inhibited MMP2 expression and JNK phosphorylation, both of which are known to be important for cell invasion and migration. Importantly, knockdown of TIMP3 in KDM1A-deficient cells rescued the metastatic capability of NSCLC cells. These findings were also confirmed by pharmacological inhibition assays. We further demonstrate that KDM1A removes H3K4me2 at the promoter of TIMP3, thus repressing the transcription of TIMP3. Finally, high expression of KDM1A and low expression of TIMP3 significantly correlate with a poor prognosis in NSCLC patients. This study establishes a mechanism by which KDM1A promotes cancer metastasis in NSCLC cells, and we suggest that KDM1A may be a potential therapeutic target for NSCLC treatment. PMID:27058897

  9. The retinoblastoma protein regulates hypoxia-inducible genetic programs, tumor cell invasiveness and neuroendocrine differentiation in prostate cancer cells

    PubMed Central

    Labrecque, Mark P.; Takhar, Mandeep K.; Nason, Rebecca; Santacruz, Stephanie; Tam, Kevin J.; Massah, Shabnam; Haegert, Anne; Bell, Robert H.; Altamirano-Dimas, Manuel; Collins, Colin C.; Lee, Frank J.S.; Prefontaine, Gratien G.; Cox, Michael E.; Beischlag, Timothy V.

    2016-01-01

    Loss of tumor suppressor proteins, such as the retinoblastoma protein (Rb), results in tumor progression and metastasis. Metastasis is facilitated by low oxygen availability within the tumor that is detected by hypoxia inducible factors (HIFs). The HIF1 complex, HIF1α and dimerization partner the aryl hydrocarbon receptor nuclear translocator (ARNT), is the master regulator of the hypoxic response. Previously, we demonstrated that Rb represses the transcriptional response to hypoxia by virtue of its association with HIF1. In this report, we further characterized the role Rb plays in mediating hypoxia-regulated genetic programs by stably ablating Rb expression with retrovirally-introduced short hairpin RNA in LNCaP and 22Rv1 human prostate cancer cells. DNA microarray analysis revealed that loss of Rb in conjunction with hypoxia leads to aberrant expression of hypoxia-regulated genetic programs that increase cell invasion and promote neuroendocrine differentiation. For the first time, we have established a direct link between hypoxic tumor environments, Rb inactivation and progression to late stage metastatic neuroendocrine prostate cancer. Understanding the molecular pathways responsible for progression of benign prostate tumors to metastasized and lethal forms will aid in the development of more effective prostate cancer therapies. PMID:27015368

  10. Involvement of S100-related calcium-binding protein pEL98 (or mts1) in cell motility and tumor cell invasion.

    PubMed

    Takenaga, K; Nakamura, Y; Endo, H; Sakiyama, S

    1994-08-01

    We examined the relationship between cell motility and the expressions of pEL98 (mts1) mRNA and protein in various murine normal and transformed cells. The expression of pEL98 (mts1) in v-Ha-ras-transformed NIH3T3 cells and in normal rat kidney cells transformed by either v-Ha-ras or v-src was increased over that in the corresponding parental cells at both mRNA and protein levels. The expression in normal rat fibroblasts (3Y1) transformed by v-Ha-ras was also increased compared with that in 3Y1 cells. However, the expression of pEL98 (mts1) in 3Y1 cells transformed by v-src was increased in one clone (src 3Y1-K), but decreased in another clone (src 3Y1-H). The expression level of pEL98 (mts1) correlated well with cell motility, which was examined by measuring cell tracks by phagokinesis. In order to test direct involvement of the pEL98 (mts1) protein in cell motility, src 3Y1-H cells that showed low cell motility were transfected with pEL98 cDNA. The transfectants expressing large amounts of the pEL98 protein showed significantly higher cell motility than src 3Y1-H cells. The expression of pEL98 (mts1) was also found to be correlated with motile and invasive abilities in various clones derived from Lewis lung carcinoma. These results suggest that the pEL98 (mts1) protein plays a role in regulating cell motility and tumor cell invasiveness. PMID:7928629

  11. Polyploidy in the Arabidopsis genus.

    PubMed

    Bomblies, Kirsten; Madlung, Andreas

    2014-06-01

    Whole genome duplication (WGD), which gives rise to polyploids, is a unique type of mutation that duplicates all the genetic material in a genome. WGD provides an evolutionary opportunity by generating abundant genetic "raw material," and has been implicated in diversification, speciation, adaptive radiation, and invasiveness, and has also played an important role in crop breeding. However, WGD at least initially challenges basic biological functions by increasing cell size, altering relationships between cell volume and DNA content, and doubling the number of homologous chromosome copies that must be sorted during cell division. Newly polyploid lineages often have extensive changes in gene regulation, genome structure, and may suffer meiotic or mitotic chromosome mis-segregation. The abundance of species that persist in nature as polyploids shows that these problems are surmountable and/or that advantages of WGD might outweigh drawbacks. The molecularly especially tractable Arabidopsis genus has several ancient polyploidy events in its history and contains several independent more recent polyploids. This genus can thus provide important insights into molecular aspects of polyploid formation, establishment, and genome evolution. The ability to integrate ecological and evolutionary questions with molecular and genetic understanding makes comparative analyses in this genus particularly attractive and holds promise for advancing our general understanding of polyploid biology. Here, we highlight some of the findings from Arabidopsis that have given us insights into the origin and evolution of polyploids. PMID:24788061

  12. Up-regulation of Histone Methyltransferase, DOT1L, by Matrix Hyaluronan Promotes MicroRNA-10 Expression Leading to Tumor Cell Invasion and Chemoresistance in Cancer Stem Cells from Head and Neck Squamous Cell Carcinoma.

    PubMed

    Bourguignon, Lilly Y W; Wong, Gabriel; Shiina, Marisa

    2016-05-13

    Human head and neck squamous cell carcinoma is a solid tumor malignancy associated with major morbidity and mortality. In this study, we determined that human head and neck squamous cell carcinoma-derived HSC-3 cells contain a subpopulation of cancer stem cells (CSCs) characterized by a high level of CD44v3 and aldehyde dehydrogenase-1 (ALDH1) expression. Importantly, matrix hyaluronan (HA) induces the up-regulation of stem cell markers that display the hallmark CSC properties. Histone methyltransferase, DOT1L, is also up-regulated by HA in CSCs (isolated from HSC-3 cells). Further analyses indicate that the stimulation of microRNA-10b (miR-10b) expression is DOT1L-specific and HA/CD44-dependent in CSCs. This process subsequently results in the overexpression of RhoGTPases and survival proteins leading to tumor cell invasion and cisplatin resistance. Treatment of CSCs with DOT1L-specific small interfering RNAs (siRNAs) effectively blocks HA/CD44-mediated expression of DOT1L, miR-10b production, and RhoGTPase/survival protein up-regulation as well as reduces tumor cell invasion and enhances chemosensitivity. CSCs were also transfected with a specific anti-miR-10b inhibitor to silence miR-10b expression and block its target functions. Our results demonstrate that the anti-miR-10 inhibitor not only decreases RhoGTPase/survival protein expression and tumor cell invasion, but also increases chemosensitivity in HA-treated CSCs. Taken together, these findings strongly support the contention that histone methyltransferase, DOT1L-associated epigenetic changes induced by HA play pivotal roles in miR-10 production leading to up-regulation of RhoGTPase and survival proteins. All of these events are critically important for the acquisition of cancer stem cell properties, including self-renewal, tumor cell invasion, and chemotherapy resistance in HA/CD44-activated head and neck cancer.

  13. Tumor cell metabolism

    PubMed Central

    Romero-Garcia, Susana; Lopez-Gonzalez, Jose Sullivan; B´ez-Viveros, José Luis; Aguilar-Cazares, Dolores

    2011-01-01

    Cancer is a genetic disease that is caused by mutations in oncogenes, tumor suppressor genes and stability genes. The fact that the metabolism of tumor cells is altered has been known for many years. However, the mechanisms and consequences of metabolic reprogramming have just begun to be understood. In this review, an integral view of tumor cell metabolism is presented, showing how metabolic pathways are reprogrammed to satisfy tumor cell proliferation and survival requirements. In tumor cells, glycolysis is strongly enhanced to fulfill the high ATP demands of these cells; glucose carbons are the main building blocks in fatty acid and nucleotide biosynthesis. Glutaminolysis is also increased to satisfy NADPH regeneration, whereas glutamine carbons replenish the Krebs cycle, which produces metabolites that are constantly used for macromolecular biosynthesis. A characteristic feature of the tumor microenvironment is acidosis, which results from the local increase in lactic acid production by tumor cells. This phenomenon is attributed to the carbons from glutamine and glucose, which are also used for lactic acid production. Lactic acidosis also directs the metabolic reprogramming of tumor cells and serves as an additional selective pressure. Finally, we also discuss the role of mitochondria in supporting tumor cell metabolism. PMID:22057267

  14. Altered Tumor-Cell Glycosylation Promotes Metastasis

    PubMed Central

    Häuselmann, Irina; Borsig, Lubor

    2014-01-01

    Malignant transformation of cells is associated with aberrant glycosylation presented on the cell-surface. Commonly observed changes in glycan structures during malignancy encompass aberrant expression and glycosylation of mucins; abnormal branching of N-glycans; and increased presence of sialic acid on proteins and glycolipids. Accumulating evidence supports the notion that the presence of certain glycan structures correlates with cancer progression by affecting tumor-cell invasiveness, ability to disseminate through the blood circulation and to metastasize in distant organs. During metastasis tumor-cell-derived glycans enable binding to cells in their microenvironment including endothelium and blood constituents through glycan-binding receptors – lectins. In this review, we will discuss current concepts how tumor-cell-derived glycans contribute to metastasis with the focus on three types of lectins: siglecs, galectins, and selectins. Siglecs are present on virtually all hematopoietic cells and usually negatively regulate immune responses. Galectins are mostly expressed by tumor cells and support tumor-cell survival. Selectins are vascular adhesion receptors that promote tumor-cell dissemination. All lectins facilitate interactions within the tumor microenvironment and thereby promote cancer progression. The identification of mechanisms how tumor glycans contribute to metastasis may help to improve diagnosis, prognosis, and aid to develop clinical strategies to prevent metastasis. PMID:24592356

  15. Molecular basis to understand polyploidy.

    PubMed

    Baatout, S

    1999-08-01

    Polyploidy which is defined as an increase in chromosome number by an exact multiple of the haploid chromosome number is a typical characteristic of plant species but can also be found in almost all organisms from protists to humans. In the plant kingdom, since the reproduction can occur vegetatively, polyploid cells have time to settle down from the evolution point of view as a stable genetic system. So, 30 to 70% of angiosperms, including many important crop plants, are estimated to have polyploidy in their lineages. The success of polyploid species in plants has been attributed to their ability to colonise a wider range of habitats and to survive better in unstable climates compared with their diploid progenitors, presumably due to increased heterozygosity and flexibility provided by the presence of additional alleles.

  16. Contractile forces in tumor cell migration.

    PubMed

    Mierke, Claudia Tanja; Rösel, Daniel; Fabry, Ben; Brábek, Jan

    2008-09-01

    Cancer is a deadly disease primarily because of the ability of tumor cells to spread from the primary tumor, to invade into the connective tissue, and to form metastases at distant sites. In contrast to cell migration on a planar surface where large cell tractions and contractile forces are not essential, tractions and forces are thought to be crucial for overcoming the resistance and steric hindrance of a dense three-dimensional connective tissue matrix. In this review, we describe recently developed biophysical tools, including 2-D and 3-D traction microscopy to measure contractile forces of cells. We discuss evidence indicating that tumor cell invasiveness is associated with increased contractile force generation.

  17. Interaction of tumor cells with the microenvironment

    PubMed Central

    2011-01-01

    Recent advances in tumor biology have revealed that a detailed analysis of the complex interactions of tumor cells with their adjacent microenvironment (tumor stroma) is mandatory in order to understand the various mechanisms involved in tumor growth and the development of metastasis. The mutual interactions between tumor cells and cellular and non-cellular components (extracellular matrix = ECM) of the tumor microenvironment will eventually lead to a loss of tissue homeostasis and promote tumor development and progression. Thus, interactions of genetically altered tumor cells and the ECM on the one hand and reactive non-neoplastic cells on the other hand essentially control most aspects of tumorigenesis such as epithelial-mesenchymal-transition (EMT), migration, invasion (i.e. migration through connective tissue), metastasis formation, neovascularisation, apoptosis and chemotherapeutic drug resistance. In this mini-review we will focus on these issues that were recently raised by two review articles in CCS. PMID:21914164

  18. The response to epidermal growth factor of human maxillary tumor cells in terms of tumor growth, invasion and expression of proteinase inhibitors.

    PubMed

    Mizoguchi, H; Komiyama, S; Matsui, K; Hamanaka, R; Ono, M; Kiue, A; Kobayashi, M; Shimizu, N; Welgus, H G; Kuwano, M

    1991-11-11

    Three cancer cell lines, IMC-2, IMC-3 and IMC-4, were established from a single tumor of a patient with maxillary cancer. We examined responses to epidermal growth factor (EGF) of these 3 cell lines with regard to cell growth and tumor invasion. The growth rate of IMC-2 in nude mice was markedly faster than that of the IMC-3 and IMC-4 cell lines. Assay for invasion through fibrin gels showed significantly enhanced invasive capacity of IMC-2 cells in response to EGF, but no change for IMC-3 and IMC-4 cells. We examined response to EGF of IMC-2 cells with regard to expression of a growth-related oncogene (c-fos), proteinases and their inhibitors. Expression of c-fos was transiently increased in IMC-2 cells at rates comparable to those seen in the 2 other lines in the presence of EGF. There was no apparent effect of EGF on the expression of urokinase-type plasminogen activator and 72-kDa type-IV collagenase in IMC-2 cells. In contrast, EGF specifically enhanced the expression of plasminogen activator inhibitor-I (PAI-I) and tissue inhibitor of metalloproteinases-I (TIMP-I) in IMC-2 cells. Our data suggest that proteinase inhibitors or other related factors may play an important role in tumor growth and invasion in response to EGF.

  19. Expression of hyaluronidase by tumor cells induces angiogenesis in vivo.

    PubMed Central

    Liu, D; Pearlman, E; Diaconu, E; Guo, K; Mori, H; Haqqi, T; Markowitz, S; Willson, J; Sy, M S

    1996-01-01

    Hyaluronic acid is a proteoglycan present in the extracellular matrix and is important for the maintenance of tissue architecture. Depolymerization of hyaluronic acid may facilitate tumor invasion. In addition, oligosaccharides of hyaluronic acid have been reported to induce angiogenesis. We report here that a hyaluronidase similar to the one on human sperm is expressed by metastatic human melanoma, colon carcinoma, and glioblastoma cell lines and by tumor biopsies from patients with colorectal carcinomas, but not by tissues from normal colon. Moreover, angiogenesis is induced by hyaluronidase+ tumor cells but not hyaluronidase- tumor cells and can be blocked by an inhibitor of hyaluronidase. Tumor cells thus use hyaluronidase as one of the "molecular saboteurs" to depolymerize hyaluronic acid to facilitate invasion. As a consequence, breakdown products of hyaluronic acid can further promote tumor establishment by inducing angiogenesis. Hyaluronidase on tumor cells may provide a target for anti-neoplastic drugs. Images Fig. 1 Fig. 2 Fig. 3 PMID:8755562

  20. Cellular apoptosis susceptibility (CAS) is linked to integrin β1 and required for tumor cell migration and invasion in hepatocellular carcinoma (HCC)

    PubMed Central

    Winkler, Juliane; Roessler, Stephanie; Sticht, Carsten; DiGuilio, Amanda L.; Drucker, Elisabeth; Holzer, Kerstin; Eiteneuer, Eva; Herpel, Esther; Breuhahn, Kai; Gretz, Norbert; Schirmacher, Peter; Ori, Alessandro; Singer, Stephan

    2016-01-01

    Importins and exportins represent an integral part of the nucleocytoplasmic transport machinery with fundamental importance for eukaryotic cell function. A variety of malignancies including hepatocellular carcinoma (HCC) show de-regulation of nuclear transport factors such as overexpression of the exportin Cellular Apoptosis Susceptibility (CAS). The functional implications of CAS in hepatocarcinogenesis remain, however, poorly understood. Here we integrated proteomics, transcriptomics and functional assays with patient data to further characterize the role of CAS in HCC. By analyzing ∼ 1700 proteins using quantitative mass spectrometry in HCC cells we found that CAS depletion by RNAi leads to de-regulation of integrins, particularly down-regulation of integrin β1. Consistent with this finding, CAS knockdown resulted in substantially reduced migration and invasion of HCC cell lines as analyzed by 2D ‘scratch’ and invasion chamber assays, respectively. Supporting the potential in vivo relevance, high expression levels of CAS in HCC tissue samples were associated with macroangioinvasion and poorer patient outcome. Our data suggest a previously unanticipated link between CAS and integrin signaling which correlates with an aggressive HCC phenotype. PMID:27015362

  1. Elevated expression of Fn14 in non-small cell lung cancer correlates with activated EGFR and promotes tumor cell migration and invasion.

    PubMed

    Whitsett, Timothy G; Cheng, Emily; Inge, Landon; Asrani, Kaushal; Jameson, Nathan M; Hostetter, Galen; Weiss, Glen J; Kingsley, Christopher B; Loftus, Joseph C; Bremner, Ross; Tran, Nhan L; Winkles, Jeffrey A

    2012-07-01

    Lung cancer is the leading cause of cancer deaths worldwide; approximately 85% of these cancers are non-small cell lung cancer (NSCLC). Patients with NSCLC frequently have tumors harboring somatic mutations in the epidermal growth factor receptor (EGFR) gene that cause constitutive receptor activation. These patients have the best clinical response to EGFR tyrosine kinase inhibitors (TKIs). Herein, we show that fibroblast growth factor-inducible 14 (Fn14; TNFRSF12A) is frequently overexpressed in NSCLC tumors, and Fn14 levels correlate with p-EGFR expression. We also report that NSCLC cell lines that contain EGFR-activating mutations show high levels of Fn14 protein expression. EGFR TKI treatment of EGFR-mutant HCC827 cells decreased Fn14 protein levels, whereas EGF stimulation of EGFR wild-type A549 cells transiently increased Fn14 expression. Furthermore, Fn14 is highly expressed in EGFR-mutant H1975 cells that also contain an EGFR TKI-resistance mutation, and high TKI doses are necessary to reduce Fn14 levels. Constructs encoding EGFRs with activating mutations induced Fn14 expression when expressed in rat lung epithelial cells. We also report that short hairpin RNA-mediated Fn14 knockdown reduced NSCLC cell migration and invasion in vitro. Finally, Fn14 overexpression enhanced NSCLC cell migration and invasion in vitro and increased experimental lung metastases in vivo. Thus, Fn14 may be a novel therapeutic target for patients with NSCLC, in particular for those with EGFR-driven tumors who have either primary or acquired resistance to EGFR TKIs. PMID:22634180

  2. Circulating Tumor Cells.

    PubMed

    Paoletti, Costanza; Hayes, Daniel F

    2016-01-01

    Circulating Tumor Cells (CTC) are shed from primary or secondary tumors. Prior studies have demonstrated that enumeration of CTC is a robust independent prognostic factor of progression free and overall survival in patients with early and metastatic breast cancer. CTC, as well as other circulating tumor markers, have the appealing advantages over tissue biopsy of (1) ease of collection, (2) serial evaluation, and (3) interrogation of the entire tumor burden instead of just a limited part of the tumor. Advances have been recently made in phenotyping and genotyping of CTC, which should provide insights into the predictive role of CTC for sensitivity or resistance to therapies. In addition, CTC phenotypic marker changes during the course of treatment may serve as pharmacodynamic monitoring tools. Therefore, CTC may be considered "liquid biopsies," providing prognostic and predictive clinical information as well as additional understanding of tumor heterogeneity.

  3. Overexpression of Rap-1A indicates a poor prognosis for oral cavity squamous cell carcinoma and promotes tumor cell invasion via Aurora-A modulation.

    PubMed

    Chen, Chang-Han; Chuang, Hui-Ching; Huang, Chao-Cheng; Fang, Fu-Min; Huang, Hsuan-Ying; Tsai, Hsin-Ting; Su, Li-Jen; Shiu, Li-Yen; Leu, Steve; Chien, Chih-Yen

    2013-02-01

    The functions of Rap-1A in oral carcinogenesis are largely unexplored. In this study, we examined the expression of Rap-1A at different malignant stages of oral cavity squamous cell carcinoma (OCSCC). Semiquantitative RT-PCR, quantitative RT-PCR, and Western blotting were used to evaluate Rap-1A mRNA and protein expressions, respectively, in paired OCSCC patient specimens. To determine the possible correlation between Rap-1A expression and various clinical characteristics, 256 samples from patients with OCSCC were evaluated by immunohistochemical staining. Strong Rap-1A expression was a significant prognostic marker and predictor of aggressive OCSCC. The overall and disease-specific 5-year survival rates were significantly correlated with strong expression of Rap-1A (P < 0.001). Functionally, overexpressed Rap-1A could promote oral cancer cell migration and invasion by Transwell chambers and wound healing assay. Conversely, the suppression of Rap-1A expression using Rap-1A-mediated siRNA was sufficient to decrease cell motility. Furthermore, our data also illustrated that Aurora-A could not only induce mRNA and protein expressions of Rap-1A for enhancing cancer cell motility but also co-localize and form a complex with Rap-1A in the oral cancer cell line. Finally, immunohistochemical staining, indirect immunofluorescence, and Western blotting analysis of human aggressive OCSCC specimens revealed a significantly positive correlation between Rap-1A and Aurora-A expression. Taken together, our results suggest that the Aurora-A/Rap-1A pathway is associated with survival, tumor progression, and metastasis of OCSCC patients.

  4. Polyploidy can drive rapid adaptation in yeast

    NASA Astrophysics Data System (ADS)

    Selmecki, Anna M.; Maruvka, Yosef E.; Richmond, Phillip A.; Guillet, Marie; Shoresh, Noam; Sorenson, Amber L.; de, Subhajyoti; Kishony, Roy; Michor, Franziska; Dowell, Robin; Pellman, David

    2015-03-01

    Polyploidy is observed across the tree of life, yet its influence on evolution remains incompletely understood. Polyploidy, usually whole-genome duplication, is proposed to alter the rate of evolutionary adaptation. This could occur through complex effects on the frequency or fitness of beneficial mutations. For example, in diverse cell types and organisms, immediately after a whole-genome duplication, newly formed polyploids missegregate chromosomes and undergo genetic instability. The instability following whole-genome duplications is thought to provide adaptive mutations in microorganisms and can promote tumorigenesis in mammalian cells. Polyploidy may also affect adaptation independently of beneficial mutations through ploidy-specific changes in cell physiology. Here we perform in vitro evolution experiments to test directly whether polyploidy can accelerate evolutionary adaptation. Compared with haploids and diploids, tetraploids undergo significantly faster adaptation. Mathematical modelling suggests that rapid adaptation of tetraploids is driven by higher rates of beneficial mutations with stronger fitness effects, which is supported by whole-genome sequencing and phenotypic analyses of evolved clones. Chromosome aneuploidy, concerted chromosome loss, and point mutations all provide large fitness gains. We identify several mutations whose beneficial effects are manifest specifically in the tetraploid strains. Together, these results provide direct quantitative evidence that in some environments polyploidy can accelerate evolutionary adaptation.

  5. Polyploidy and ecological adaptation in wild yarrow

    PubMed Central

    Ramsey, Justin

    2011-01-01

    Chromosome evolution in flowering plants is often punctuated by polyploidy, genome duplication events that fundamentally alter DNA content, chromosome number, and gene dosage. Polyploidy confers postzygotic reproductive isolation and is thought to drive ecological divergence and range expansion. The adaptive value of polyploidy, however, remains uncertain; ecologists have traditionally relied on observational methods that cannot distinguish effects of polyploidy per se from genic differences that accumulate after genome duplication. Here I use an experimental approach to test how polyploidy mediates ecological divergence in Achillea borealis (Asteraceae), a widespread tetraploid plant with localized hexaploid populations. In coastal California, tetraploids and hexaploids occupy mesic grassland and xeric dune habitats, respectively. Using field transplant experiments with wild-collected plants, I show that hexaploids have a fivefold fitness advantage over tetraploids in dune habitats. Parallel experiments with neohexaploids—first-generation mutants screened from a tetraploid genetic background—reveal that a 70% fitness advantage is achieved via genome duplication per se. These results suggest that genome duplication transforms features of A. borealis in a manner that confers adaptation to a novel environment. PMID:21402904

  6. Polyploidy can drive rapid adaptation in yeast

    PubMed Central

    Selmecki, Anna; Maruvka, Yosef E.; Richmond, Phillip A.; Guillet, Marie; Shoresh, Noam; Sorenson, Amber; De, Subhajyoti; Kishony, Roy; Michor, Franziska; Dowell, Robin; Pellman, David

    2015-01-01

    Polyploidy is observed across the tree of life, yet its influence on evolution remains incompletely understood1–4. Polyploidy, usually whole genome duplication (WGD), is proposed to alter the rate of evolutionary adaptation. This could occur through complex effects on the frequency or fitness of beneficial mutations 2,5–7. For example, in diverse cell types and organisms, immediately after a WGD, newly formed polyploids missegregate chromosomes and undergo genetic instability8–13. The instability following WGDs is thought to provide adaptive mutations in microorganisms13,14 and can promote tumorigenesis in mammalian cells11,15. Polyploidy may also affect adaptation independent of beneficial mutations through ploidy-specific changes in cell physiology16. Here, we performed in vitro evolution experiments to directly test whether polyploidy can accelerate evolutionary adaptation. Compared to haploids and diploids, tetraploids underwent significantly faster adaptation. Mathematical modeling suggested that rapid adaptation of tetraploids was driven by higher rates of beneficial mutations with stronger fitness effects, which was supported by whole-genome sequencing and phenotypic analyses of evolved clones. Chromosome aneuploidy, concerted chromosome loss, and point mutations all provided large fitness gains. We identified several mutations whose beneficial effects were manifest specifically in the tetraploid strains. Together, these results provide direct quantitative evidence that in some environments polyploidy can accelerate evolutionary adaptation. PMID:25731168

  7. A paracrine loop between tumor cells and macrophages is required for tumor cell migration in mammary tumors.

    PubMed

    Wyckoff, Jeffrey; Wang, Weigang; Lin, Elaine Y; Wang, Yarong; Pixley, Fiona; Stanley, E Richard; Graf, Thomas; Pollard, Jeffrey W; Segall, Jeffrey; Condeelis, John

    2004-10-01

    Invasion of tumor cells into the surrounding connective tissue and blood vessels is a key step in the metastatic spread of breast tumors. Although the presence of macrophages in primary tumors is associated with increased metastatic potential, the mechanistic basis for this observation is unknown. Using a chemotaxis-based in vivo invasion assay and multiphoton-based intravital imaging, we show that the interaction between macrophages and tumor cells facilitates the migration of carcinoma cells in the primary tumor. Gradients of either epidermal growth factor (EGF) or colony-stimulating factor 1 (CSF-1) stimulate collection into microneedles of tumor cells and macrophages even though tumor cells express only EGF receptor and macrophages express only CSF-1 receptor. Intravital imaging shows that macrophages and tumor cells migrate toward microneedles containing either EGF or CSF-1. Inhibition of either CSF-1- or EGF-stimulated signaling reduces the migration of both cell types. This work provides the first direct evidence for a synergistic interaction between macrophages and tumor cells during cell migration in vivo and indicates a mechanism for how macrophages may contribute to metastasis.

  8. Curcumin targets fibroblast–tumor cell interactions in oral squamous cell carcinoma

    SciTech Connect

    Dudás, József; Fullár, Alexandra; Romani, Angela; Pritz, Christian; Kovalszky, Ilona; Hans Schartinger, Volker; Mathias Sprinzl, Georg; Riechelmann, Herbert

    2013-04-01

    Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of OSCC tumor cells. We hypothesized that Curcumin targets this dynamic mutual interaction between CAFs and tumor cells. Normal and 2 μM Curcumin-treated co-culture were performed for 4 days, followed by analysis of tumor cell invasivity, mRNA/protein expression of EMT-markers and mediators, activity measure of matrix metalloproteinase 9 (MMP-9), and western blot analysis of signal transduction in tumor cells and fibroblasts. In Curcumin-treated co-culture, in tumor cells, the levels of nuclear factor κB (NFκBα) and early response kinase (ERK)—decreased, in fibroblasts, integrin αv protein synthesis decreased compared to corresponding cells in normal co-culture. The signal modulatory changes induced by Curcumin caused decreased release of EMT-mediators in CAFs and reversal of EMT in tumor cells, which was associated with decreased invasion. These data confirm the palliative potential of Curcumin in clinical application. - Graphical abstract: Co-culture of periodontal ligament fibroblasts (PDLs) and SCC-25 oral squamous carcinoma cells (OSCC) results in conversion of PDLs into carcinoma-associated fibroblasts (CAFs) and induces epithelial-to mesenchymal transition (EMT) of tumor cells. Curcumin targets this dynamic mutual interaction between CAFs and tumor cells by inhibiting the production of EMT mediators in CAFs and by modification of intracellular signaling in tumor cells. This causes less invasivity and reversal of EMT in tumor cells. Highlights: ► Curcumin targets tumor–fibroblast interaction in head and neck cancer. ► Curcumin suppresses mediators of epithelial–mesenchymal transition. ► Curcumin decreases the invasivity of tumor cells.

  9. Circulating tumor cells in germ cell tumors: are those biomarkers of real prognostic value? A review

    PubMed Central

    CEBOTARU, CRISTINA LIGIA; OLTEANU, ELENA DIANA; ANTONE, NICOLETA ZENOVIA; BUIGA, RARES; NAGY, VIORICA

    2016-01-01

    Analysis of circulating tumor cells from patients with different types of cancer is nowadays a fascinating new tool of research and their number is proven to be useful as a prognostic factor in metastatic breast, colon and prostate cancer patients. Studies are going beyond enumeration, exploring the circulating tumor cells to better understand the mechanisms of tumorigenesis, invasion and metastasis and their value for characterization, prognosis and tailoring of treatment. Few studies investigated the prognostic significance of circulating tumor cells in germ cell tumors. In this review, we examine the possible significance of the detection of circulating tumor cells in this setting. PMID:27152069

  10. Detection of circulating tumor cells.

    PubMed

    de Wit, Sanne; van Dalum, Guus; Terstappen, Leon W M M

    2014-01-01

    The increasing number of treatment options for patients with metastatic carcinomas has created an accompanying need for methods to determine if the tumor will be responsive to the intended therapy and to monitor its effectiveness. Ideally, these methods would be noninvasive and provide quantitative real-time analysis of tumor activity in a variety of carcinomas. Assessment of circulating tumor cells shed into the blood during metastasis may satisfy this need. Here we review the CellSearch technology used for the detection of circulating tumor cells and discuss potential future directions for improvements.

  11. Detection of Circulating Tumor Cells

    PubMed Central

    Terstappen, Leon W. M. M.

    2014-01-01

    The increasing number of treatment options for patients with metastatic carcinomas has created an accompanying need for methods to determine if the tumor will be responsive to the intended therapy and to monitor its effectiveness. Ideally, these methods would be noninvasive and provide quantitative real-time analysis of tumor activity in a variety of carcinomas. Assessment of circulating tumor cells shed into the blood during metastasis may satisfy this need. Here we review the CellSearch technology used for the detection of circulating tumor cells and discuss potential future directions for improvements. PMID:25133014

  12. Tumor heterogeneity and circulating tumor cells.

    PubMed

    Zhang, Chufeng; Guan, Yan; Sun, Yulan; Ai, Dan; Guo, Qisen

    2016-05-01

    In patients with cancer, individualized treatment strategies are generally guided by an analysis of molecular biomarkers. However, genetic instability allows tumor cells to lose monoclonality and acquire genetic heterogeneity, an important characteristic of tumors, during disease progression. Researchers have found that there is tumor heterogeneity between the primary tumor and metastatic lesions, between different metastatic lesions, and even within a single tumor (either primary or metastatic). Tumor heterogeneity is associated with heterogeneous protein functions, which lowers diagnostic precision and consequently becomes an obstacle to determining the appropriate therapeutic strategies for individual cancer patients. With the development of novel testing technologies, an increasing number of studies have attempted to explore tumor heterogeneity by examining circulating tumor cells (CTCs), with the expectation that CTCs may comprehensively represent the full spectrum of mutations and/or protein expression alterations present in the cancer. In addition, this strategy represents a minimally invasive approach compared to traditional tissue biopsies that can be used to dynamically monitor tumor evolution. The present article reviews the potential efficacy of using CTCs to identify both spatial and temporal tumor heterogeneity. This review also highlights current issues in this field and provides an outlook toward future applications of CTCs.

  13. The biology of circulating tumor cells.

    PubMed

    Pantel, K; Speicher, M R

    2016-03-10

    Metastasis is a biologically complex process consisting of numerous stochastic events which may tremendously differ across various cancer types. Circulating tumor cells (CTCs) are cells that are shed from primary tumors and metastatic deposits into the blood stream. CTCs bear a tremendous potential to improve our understanding of steps involved in the metastatic cascade, starting from intravasation of tumor cells into the circulation until the formation of clinically detectable metastasis. These efforts were propelled by novel high-resolution approaches to dissect the genomes and transcriptomes of CTCs. Furthermore, capturing of viable CTCs has paved the way for innovative culturing technologies to study fundamental characteristics of CTCs such as invasiveness, their kinetics and responses to selection barriers, such as given therapies. Hence the study of CTCs is not only instrumental as a basic research tool, but also allows the serial monitoring of tumor genotypes and may therefore provide predictive and prognostic biomarkers for clinicians. Here, we review how CTCs have contributed to significant insights into the metastatic process and how they may be utilized in clinical practice.

  14. Patterns of invasive growth in vitro. Human decidua graviditatis confronted with established human cell lines and primary human explants.

    PubMed

    Schleich, A B; Frick, M; Mayer, A

    1976-02-01

    Human decidua graviditatis was used as a receptor tissue to demonstrate invasive properties of human cells in vitro. In the confrontation between decidua and established cell lines of tumors and of normal origin as well as primary explanted cells, we noted differences in the cells' interactions with decidual tissue. The two original tumor cell lines, HeLa (carcinoma) and AFi (sarcoma), and a spontaneously transformed lymphoblastoid cell line showed aggressiveness, i.e., invasion, rapid proliferation, injury, and destruction of the decidual tissue. Strain HeLa S3 and two established cell lines, FL (amnion) and Girardi Heart, which are regarded as transformed cells because of their increased mitotic rate and polyploidy, exhibited various degrees of aggressiveness but did not invade. Freshly explanted fetal lung and endometrium caused no injury to the receptor tissue and were included in the decidual tissue.

  15. Physical Biology in Cancer. 4. Physical cues guide tumor cell adhesion and migration

    PubMed Central

    Stroka, Kimberly M.

    2013-01-01

    As tumor cells metastasize from the primary tumor location to a distant secondary site, they encounter an array of biologically and physically heterogeneous microenvironments. While it is well established that biochemical signals guide all stages of the metastatic cascade, mounting evidence indicates that physical cues also direct tumor cell behavior, including adhesion and migration phenotypes. Physical cues acting on tumor cells in vivo include extracellular matrix mechanical properties, dimensionality, and topography, as well as interstitial flow, hydrodynamic shear stresses, and local forces due to neighboring cells. State-of-the-art technologies have recently enabled us and other researchers to engineer cell microenvironments that mimic specific physical properties of the cellular milieu. Through integration of these engineering strategies, along with physics, molecular biology, and imaging techniques, we have acquired new insights into tumor cell adhesion and migration mechanisms. In this review, we focus on the extravasation and invasion stages of the metastatic cascade. We first discuss the physical role of the endothelium during tumor cell extravasation and invasion and how contractility of endothelial and tumor cells contributes to the ability of tumor cells to exit the vasculature. Next, we examine how matrix dimensionality and stiffness coregulate tumor cell adhesion and migration beyond the vasculature. Finally, we summarize how tumor cells translate and respond to physical cues through mechanotransduction. Because of the critical role of tumor cell mechanotransduction at various stages of the metastatic cascade, targeting signaling pathways involved in tumor cell mechanosensing of physical stimuli may prove to be an effective therapeutic strategy for cancer patients. PMID:24133064

  16. The polyploidy revolution then…and now: Stebbins revisited.

    PubMed

    Soltis, Douglas E; Visger, Clayton J; Soltis, Pamela S

    2014-07-20

    Polyploidy has long been considered a major force in plant evolution. G. Ledyard Stebbins, Jr., an architect of the Modern Synthesis, elegantly addressed a broad range of topics, from genes to chromosomes to deep phylogeny, but some of his most lasting insights came in the study of polyploidy. Here, we review the immense impact of his work on polyploidy over more than 60 years, from his entrance into this fledgling field in the 1920s until the end of his career. Stebbins and his contemporaries developed a model of polyploid evolution that persisted for nearly half a century. As new perspectives emerged in the 1980s and new genetic tools for addressing key aspects of polyploidy have become available, a new paradigm of polyploidy has replaced much of the Stebbinsian framework. We review that paradigm shift and emphasize those areas in which the ideas of Stebbins continue to propel the field forward, as well as those areas in which the field was held back; we also note new directions that plant geneticists and evolutionists are now exploring in polyploidy research. Perhaps the most important conclusion from recent and ongoing studies of polyploidy is that, following Levin and others, polyploidy may propel a population into a new adaptive sphere given the myriad changes that accompany genome doubling.

  17. Has the connection between polyploidy and diversification actually been tested?

    PubMed

    Kellogg, Elizabeth A

    2016-04-01

    Many major clades of angiosperms have several whole genome duplications (polyploidization events) in their distant past, suggesting that polyploidy drives or at least permits diversification. However, data on recently diverged groups are more equivocal, finding little evidence of elevated diversification following polyploidy. The discrepancy may be attributable at least in part to methodology. Many studies use indirect methods, such as chromosome numbers, genome size, and Ks plots, to test polyploidy, although these approaches can be misleading, and often lack sufficient resolution. A direct test of diversification following polyploidy requires a sequence-based approach that traces the history of nuclear genomes rather than species. These methods identify the point of coalescence of ancestral genomes, but may be misleading about the time and thus the extent of diversification. Limitations of existing methods mean that the connection between polyploidy and diversification has not been rigorously tested and remains unknown.

  18. Polyploidy in fungi: evolution after whole-genome duplication

    PubMed Central

    Albertin, Warren; Marullo, Philippe

    2012-01-01

    Polyploidy is a major evolutionary process in eukaryotes—particularly in plants and, to a less extent, in animals, wherein several past and recent whole-genome duplication events have been described. Surprisingly, the incidence of polyploidy in other eukaryote kingdoms, particularly within fungi, remained largely disregarded by the scientific community working on the evolutionary consequences of polyploidy. Recent studies have significantly increased our knowledge of the occurrence and evolutionary significance of fungal polyploidy. The ecological, structural and functional consequences of polyploidy in fungi are reviewed here and compared with the knowledge acquired with conventional plant and animal models. In particular, the genus Saccharomyces emerges as a relevant model for polyploid studies, in addition to plant and animal models. PMID:22492065

  19. Automated genotyping of circulating tumor cells.

    PubMed

    Stakenborg, Tim; Liu, Chengxun; Henry, Olivier; Borgen, Elin; Laddach, Nadja; Roeser, Tina; Ritzi-Lehnert, Marion; Fermér, Christian; Hauch, Sigfried; O'Sullivan, Ciara K; Lagae, Liesbet

    2010-09-01

    Cancer remains a prominent health concern in modern societies. Continuous innovations and introduction of new technologies are essential to level or reduce current healthcare spending. A diagnostic platform to detect circulating tumor cells (CTCs) in peripheral blood may be most promising in this respect. CTCs have been proposed as a minimally invasive, prognostic and predictive marker to reflect the biological characteristics of tumors and are implemented in an increasing number of clinical studies. Still, their detection remains a challenge as they may occur at concentrations below one single cell per ml of blood. To facilitate their detection, here we describe microfluidic modules to isolate and genotype CTCs directly from clinical blood samples. In a first cell isolation and detection module, the CTCs are immunomagnetically enriched, separated and counted. In a second module and after cell lysis, the mRNA is reversely transcripted to cDNA, followed by a multiplex ligation probe amplification of 20 specific genetic markers and two control fragments. Following the multiplex ligation probe amplification reaction, the amplified fragments are electrochemically detected in a third and final module. Besides the design of the modules, their functionality is described using control samples. Further testing using clinical samples and integration of all modules in a single, fully automated smart miniaturized system will enable minimal invasive testing for frequent detection and characterization of CTCs.

  20. Effects of polyploidy and reproductive mode on life history trait expression.

    PubMed

    Larkin, Katelyn; Tucci, Claire; Neiman, Maurine

    2016-02-01

    Ploidy elevation is increasingly recognized as a common and important source of genomic variation. Even so, the consequences and biological significance of polyploidy remain unclear, especially in animals. Here, our goal was to identify potential life history costs and benefits of polyploidy by conducting a large multiyear common garden experiment in Potamopyrgus antipodarum, a New Zealand freshwater snail that is a model system for the study of ploidy variation, sexual reproduction, host-parasite coevolution, and invasion ecology. Sexual diploid and asexual triploid and tetraploid P. antipodarum frequently coexist, allowing for powerful direct comparisons across ploidy levels and reproductive modes. Asexual reproduction and polyploidy are very often associated in animals, allowing us to also use these comparisons to address the maintenance of sex, itself one of the most important unresolved questions in evolutionary biology. Our study revealed that sexual diploid P. antipodarum grow and mature substantially more slowly than their asexual polyploid counterparts. We detected a strong negative correlation between the rate of growth and age at reproductive maturity, suggesting that the relatively early maturation of asexual polyploid P. antipodarum is driven by relatively rapid growth. The absence of evidence for life history differences between triploid and tetraploid asexuals indicates that ploidy elevation is unlikely to underlie the differences in trait values that we detected between sexual and asexual snails. Finally, we found that sexual P. antipodarum did not experience discernable phenotypic variance-related benefits of sex and were more likely to die before achieving reproductive maturity than the asexuals. Taken together, these results suggest that under benign conditions, polyploidy does not impose obvious life history costs in P. antipodarum and that sexual P. antipodarum persist despite substantial life history disadvantages relative to their asexual

  1. Effects of polyploidy and reproductive mode on life history trait expression.

    PubMed

    Larkin, Katelyn; Tucci, Claire; Neiman, Maurine

    2016-02-01

    Ploidy elevation is increasingly recognized as a common and important source of genomic variation. Even so, the consequences and biological significance of polyploidy remain unclear, especially in animals. Here, our goal was to identify potential life history costs and benefits of polyploidy by conducting a large multiyear common garden experiment in Potamopyrgus antipodarum, a New Zealand freshwater snail that is a model system for the study of ploidy variation, sexual reproduction, host-parasite coevolution, and invasion ecology. Sexual diploid and asexual triploid and tetraploid P. antipodarum frequently coexist, allowing for powerful direct comparisons across ploidy levels and reproductive modes. Asexual reproduction and polyploidy are very often associated in animals, allowing us to also use these comparisons to address the maintenance of sex, itself one of the most important unresolved questions in evolutionary biology. Our study revealed that sexual diploid P. antipodarum grow and mature substantially more slowly than their asexual polyploid counterparts. We detected a strong negative correlation between the rate of growth and age at reproductive maturity, suggesting that the relatively early maturation of asexual polyploid P. antipodarum is driven by relatively rapid growth. The absence of evidence for life history differences between triploid and tetraploid asexuals indicates that ploidy elevation is unlikely to underlie the differences in trait values that we detected between sexual and asexual snails. Finally, we found that sexual P. antipodarum did not experience discernable phenotypic variance-related benefits of sex and were more likely to die before achieving reproductive maturity than the asexuals. Taken together, these results suggest that under benign conditions, polyploidy does not impose obvious life history costs in P. antipodarum and that sexual P. antipodarum persist despite substantial life history disadvantages relative to their asexual

  2. Metastasis and Circulating Tumor Cells.

    PubMed

    van Dalum, Guus; Holland, Linda; Terstappen, Leon Wmm

    2012-10-01

    Cancer is a prominent cause of death worldwide. In most cases, it is not the primary tumor which causes death, but the metastases. Metastatic tumors are spread over the entire human body and are more difficult to remove or treat than the primary tumor. In a patient with metastatic disease, circulating tumor cells (CTCs) can be found in venous blood. These circulating tumor cells are part of the metastatic cascade. Clinical studies have shown that these cells can be used to predict treatment response and their presence is strongly associated with poor survival prospects. Enumeration and characterization of CTCs is important as this can help clinicians make more informed decisions when choosing or evaluating treatment. CTC counts are being included in an increasing number of studies and thus are becoming a bigger part of disease diagnosis and therapy management. We present an overview of the most prominent CTC enumeration and characterization methods and discuss the assumptions made about the CTC phenotype. Extensive CTC characterization of for example the DNA, RNA and antigen expression may lead to more understanding of the metastatic process.

  3. Metastasis and Circulating Tumor Cells

    PubMed Central

    van Dalum, Guus; Holland, Linda

    2012-01-01

    Cancer is a prominent cause of death worldwide. In most cases, it is not the primary tumor which causes death, but the metastases. Metastatic tumors are spread over the entire human body and are more difficult to remove or treat than the primary tumor. In a patient with metastatic disease, circulating tumor cells (CTCs) can be found in venous blood. These circulating tumor cells are part of the metastatic cascade. Clinical studies have shown that these cells can be used to predict treatment response and their presence is strongly associated with poor survival prospects. Enumeration and characterization of CTCs is important as this can help clinicians make more informed decisions when choosing or evaluating treatment. CTC counts are being included in an increasing number of studies and thus are becoming a bigger part of disease diagnosis and therapy management. We present an overview of the most prominent CTC enumeration and characterization methods and discuss the assumptions made about the CTC phenotype. Extensive CTC characterization of for example the DNA, RNA and antigen expression may lead to more understanding of the metastatic process. PMID:27683421

  4. Metastasis and Circulating Tumor Cells

    PubMed Central

    van Dalum, Guus; Holland, Linda

    2012-01-01

    Cancer is a prominent cause of death worldwide. In most cases, it is not the primary tumor which causes death, but the metastases. Metastatic tumors are spread over the entire human body and are more difficult to remove or treat than the primary tumor. In a patient with metastatic disease, circulating tumor cells (CTCs) can be found in venous blood. These circulating tumor cells are part of the metastatic cascade. Clinical studies have shown that these cells can be used to predict treatment response and their presence is strongly associated with poor survival prospects. Enumeration and characterization of CTCs is important as this can help clinicians make more informed decisions when choosing or evaluating treatment. CTC counts are being included in an increasing number of studies and thus are becoming a bigger part of disease diagnosis and therapy management. We present an overview of the most prominent CTC enumeration and characterization methods and discuss the assumptions made about the CTC phenotype. Extensive CTC characterization of for example the DNA, RNA and antigen expression may lead to more understanding of the metastatic process.

  5. Three-dimensional chemotaxis-driven aggregation of tumor cells

    PubMed Central

    Puliafito, Alberto; De Simone, Alessandro; Seano, Giorgio; Gagliardi, Paolo Armando; Di Blasio, Laura; Chianale, Federica; Gamba, Andrea; Primo, Luca; Celani, Antonio

    2015-01-01

    One of the most important steps in tumor progression involves the transformation from a differentiated epithelial phenotype to an aggressive, highly motile phenotype, where tumor cells invade neighboring tissues. Invasion can occur either by isolated mesenchymal cells or by aggregates that migrate collectively and do not lose completely the epithelial phenotype. Here, we show that, in a three-dimensional cancer cell culture, collective migration of cells eventually leads to aggregation in large clusters. We present quantitative measurements of cluster velocity, coalescence rates, and proliferation rates. These results cannot be explained in terms of random aggregation. Instead, a model of chemotaxis-driven aggregation – mediated by a diffusible attractant – is able to capture several quantitative aspects of our results. Experimental assays of chemotaxis towards culture conditioned media confirm this hypothesis. Theoretical and numerical results further suggest an important role for chemotactic-driven aggregation in spreading and survival of tumor cells. PMID:26471876

  6. Circulating Tumor Cells in Breast Cancer Patients.

    PubMed

    Hall, Carolyn; Valad, Lily; Lucci, Anthony

    2016-01-01

    Breast cancer is the most commonly diagnosed cancer among women, resulting in an estimated 40,000 deaths in 2014.1 Metastasis, a complex, multi-step process, remains the primary cause of death for these patients. Although the mechanisms involved in metastasis have not been fully elucidated, considerable evidence suggests that metastatic spread is mediated by rare cells within the heterogeneous primary tumor that acquire the ability to invade into the bloodstream. In the bloodstream, they can travel to distant sites, sometimes remaining undetected and in a quiescent state for an extended period of time before they establish distant metastases in the bone, lung, liver, or brain. These occult micrometastatic cells (circulating tumor cells, CTCs) are rare, yet their prognostic significance has been demonstrated in both metastatic and non-metastatic breast cancer patients. Because repeated tumor tissue collection is typically not feasible and peripheral blood draws are minimally invasive, serial CTC enumeration might provide "real-time liquid biopsy" snapshots that could be used to identify early-stage breast cancer patients with micrometastatic disease who are at risk for disease progression and monitor treatment response in patients with advanced disease. In addition, characterizing CTCs might aid in the development of novel, personalized therapies aimed at eliminating micrometastases. This review describes current CTC isolation, detection, and characterization strategies in operable breast cancer. PMID:27481009

  7. Investigating Polyploidy: Using Marigold Stomates and Fingernail Polish.

    ERIC Educational Resources Information Center

    Hunter, Kimberly L.; Leone, Rebecca S.; Kohlhepp, Kimberly; Hunter, Richard B.

    2002-01-01

    Describes a science activity on polyploidy targeting middle and high school students which can be used to discuss topics such as chromosomes, cells, plant growth, and functions of stomates. Integrates mathematics in data collection. (Contains 13 references.) (YDS)

  8. Different cell fates after mitotic slippage: From aneuploidy to polyploidy.

    PubMed

    Ohashi, Akihiro

    2016-03-01

    The molecular mechanism responsible for cell fate after mitotic slippage remains unclear. We investigated the different postmitotic effects of aneuploidy versus polyploidy using chemical inhibitors of centromere-associated protein-E (CENP-E) and kinesin family member 11 (KIF11, also known as Eg5). Aneuploidy caused substantial proteotoxic stress and DNA damage accompanied by p53-mediated postmitotic apoptosis, whereas polyploidy did not induce these antiproliferative effects. PMID:27308610

  9. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    PubMed

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  10. Natural polyploidy in Vanilla planifolia (Orchidaceae).

    PubMed

    Bory, Séverine; Catrice, Olivier; Brown, Spencer; Leitch, Ilia J; Gigant, Rodolphe; Chiroleu, Frédéric; Grisoni, Michel; Duval, Marie-France; Besse, Pascale

    2008-10-01

    Vanilla planifolia accessions cultivated in Reunion Island display important phenotypic variation, but little genetic diversity is demonstrated by AFLP and SSR markers. This study, based on analyses of flow cytometry data, Feulgen microdensitometry data, chromosome counts, and stomatal length measurements, was performed to determine whether polyploidy could be responsible for some of the intraspecific phenotypic variation observed. Vanilla planifolia exhibited an important variation in somatic chromosome number in root cells, as well as endoreplication as revealed by flow cytometry. Nevertheless, the 2C-values of the 50 accessions studied segregated into three distinct groups averaging 5.03 pg (for most accessions), 7.67 pg (for the 'Stérile' phenotypes), and 10.00 pg (for the 'Grosse Vanille' phenotypes). For the three groups, chromosome numbers varied from 16 to 32, 16 to 38, and 22 to 54 chromosomes per cell, respectively. The stomatal length showed a significant variation from 37.75 microm to 48.25 microm. Given that 2C-values, mean chromosome numbers, and stomatal lengths were positively correlated and that 'Stérile' and 'Grosse Vanille' accessions were indistinguishable from 'Classique' accessions using molecular markers, the occurrence of recent autotriploid and autotetraploid types in Reunion Island is supported. This is the first report showing evidence of a recent autopolyploidy in V. planifolia contributing to the phenotypic variation observed in this species.

  11. Polyploidy in pleomorphic adenomas with cytological atypia.

    PubMed

    Thunnissen, F B; Peterse, J L; Buchholtz, R; Van der Beek, J M; Bosman, F T

    1992-01-01

    Occasionally, in fine-needle aspirates of pleomorphic salivary gland adenomas, considerable cytonuclear atypia is present, which may give rise to a false-positive diagnosis. In this study DNA cytophotometry was performed on Feulgen restained smears prepared from material obtained by needle aspirates of normal salivary glands (n = 4), pleomorphic adenomas with (n = 5) and without (n = 4) atypia and a carcinoma in a pleomorphic adenoma. The results showed a clear diploid DNA histogram in the specimens of normal salivary gland and pleomorphic adenomas without atypia. In contrast, in the pleomorphic adenomas with atypia a distinct polyploid pattern was present in three out of the five DNA histograms with DNA values in 2c, 4c and 8c ranges. In two of these cases a 16c peak was also present and in the two remaining cases tetraploidy was demonstrated. In the carcinoma a main stemline at 4c was found. This report once more emphasizes the possible atypia which may be present in FNA of pleomorphic adenomas of the salivary gland. The atypia is due to polyploidy in a histologically benign tumour.

  12. SNAP23, Syntaxin4, and vesicle-associated membrane protein 7 (VAMP7) mediate trafficking of membrane type 1-matrix metalloproteinase (MT1-MMP) during invadopodium formation and tumor cell invasion.

    PubMed

    Williams, Karla C; McNeilly, Rachael E; Coppolino, Marc G

    2014-07-01

    Movement through the extracellular matrix (ECM) requires cells to degrade ECM components, primarily through the action of matrix metalloproteinases (MMPs). Membrane type 1-matrix metalloproteinase (MT1-MMP) has an essential role in matrix degradation and cell invasion and localizes to subcellular degradative structures termed invadopodia. Trafficking of MT1-MMP to invadopodia is required for the function of these structures, and here we examine the role of N-ethylmaleimide-sensitive factor-activating protein receptor (SNARE)-mediated membrane traffic in the transport of MT1-MMP to invadopodia. During invadopodium formation in MDA-MB-231 human breast cancer cells, increased association of SNAP23, Syntaxin4, and vesicle-associated membrane protein 7 (VAMP7) is detected by coimmunoprecipitation. Blocking the function of these SNAREs perturbs invadopodium-based ECM degradation and cell invasion. Increased level of SNAP23-Syntaxin4-VAMP7 interaction correlates with decreased Syntaxin4 phosphorylation. These results reveal an important role for SNARE-regulated trafficking of MT1-MMP to invadopodia during cellular invasion of ECM.

  13. PIK3R1 targeting by miR-21 suppresses tumor cell migration and invasion by reducing PI3K/AKT signaling and reversing EMT, and predicts clinical outcome of breast cancer.

    PubMed

    Yan, Li-Xu; Liu, Yan-Hui; Xiang, Jian-Wen; Wu, Qi-Nian; Xu, Lei-Bo; Luo, Xin-Lan; Zhu, Xiao-Lan; Liu, Chao; Xu, Fang-Ping; Luo, Dong-Lan; Mei, Ping; Xu, Jie; Zhang, Ke-Ping; Chen, Jie

    2016-02-01

    We have previously shown that dysregulation of miR-21 functioned as an oncomiR in breast cancer. The aim of the present study was to elucidate the mechanisms by which miR-21 regulate breast tumor migration and invasion. We applied pathway analysis on genome microarray data and target-predicting algorithms for miR-21 target screening, and used luciferase reporting assay to confirm the direct target. Thereafter, we investigated the function of the target gene phosphoinositide-3-kinase, regulatory subunit 1 (α) (PIK3R1), and detected PIK3R1 coding protein (p85α) by immunohistochemistry and miR-21 by RT-qPCR on 320 archival paraffin-embedded tissues of breast cancer to evaluate the correlation of their expression with prognosis. First, we found that PIK3R1 suppressed growth, invasiveness, and metastatic properties of breast cancer cells. Next, we identified the PIK3R1 as a direct target of miR-21 and showed that it was negatively regulated by miR-21. Furthermore, we demonstrated that p85α overexpression phenocopied the suppression effects of antimiR-21 on breast cancer cell growth, migration and invasion, indicating its tumor suppressor role in breast cancer. On the contrary, PIK3R1 knockdown abrogated antimiR‑21-induced effect on breast cancer cells. Notably, antimiR-21 induction increased p85α, accompanied by decreased p-AKT level. Besides, antimiR-21/PIK3R1-induced suppression of invasiveness in breast cancer cells was mediated by reversing epithelial-mesenchymal transition (EMT). p85α downregulation was found in 25 (7.8%) of the 320 breast cancer patients, and was associated with inferior 5-year disease-free survival (DFS) and overall survival (OS). Taken together, we provide novel evidence that miR-21 knockdown suppresses cell growth, migration and invasion partly by inhibiting PI3K/AKT activation via direct targeting PIK3R1 and reversing EMT in breast cancer. p85α downregulation defined a specific subgroup of breast cancer with shorter 5-year DFS and OS

  14. PIK3R1 targeting by miR-21 suppresses tumor cell migration and invasion by reducing PI3K/AKT signaling and reversing EMT, and predicts clinical outcome of breast cancer

    PubMed Central

    YAN, LI-XU; LIU, YAN-HUI; XIANG, JIAN-WEN; WU, QI-NIAN; XU, LEI-BO; LUO, XIN-LAN; ZHU, XIAO-LAN; LIU, CHAO; XU, FANG-PING; LUO, DONG-LAN; MEI, PING; XU, JIE; ZHANG, KE-PING; CHEN, JIE

    2016-01-01

    We have previously shown that dysregulation of miR-21 functioned as an oncomiR in breast cancer. The aim of the present study was to elucidate the mechanisms by which miR-21 regulate breast tumor migration and invasion. We applied pathway analysis on genome microarray data and target-predicting algorithms for miR-21 target screening, and used luciferase reporting assay to confirm the direct target. Thereafter, we investigated the function of the target gene phosphoinositide-3-kinase, regulatory subunit 1 (α) (PIK3R1), and detected PIK3R1 coding protein (p85α) by immunohistochemistry and miR-21 by RT-qPCR on 320 archival paraffin-embedded tissues of breast cancer to evaluate the correlation of their expression with prognosis. First, we found that PIK3R1 suppressed growth, invasiveness, and metastatic properties of breast cancer cells. Next, we identified the PIK3R1 as a direct target of miR-21 and showed that it was negatively regulated by miR-21. Furthermore, we demonstrated that p85α overexpression phenocopied the suppression effects of antimiR-21 on breast cancer cell growth, migration and invasion, indicating its tumor suppressor role in breast cancer. On the contrary, PIK3R1 knockdown abrogated antimiR-21-induced effect on breast cancer cells. Notably, antimiR-21 induction increased p85α, accompanied by decreased p-AKT level. Besides, antimiR-21/PIK3R1-induced suppression of invasiveness in breast cancer cells was mediated by reversing epithelial-mesenchymal transition (EMT). p85α downregulation was found in 25 (7.8%) of the 320 breast cancer patients, and was associated with inferior 5-year disease-free survival (DFS) and overall survival (OS). Taken together, we provide novel evidence that miR-21 knockdown suppresses cell growth, migration and invasion partly by inhibiting PI3K/AKT activation via direct targeting PIK3R1 and reversing EMT in breast cancer. p85α downregulation defined a specific subgroup of breast cancer with shorter 5-year DFS and OS

  15. Patient-Derived Antibody Targets Tumor Cells

    Cancer.gov

    An NCI Cancer Currents blog on an antibody derived from patients that killed tumor cells in cell lines of several cancer types and slowed tumor growth in mouse models of brain and lung cancer without evidence of side effects.

  16. Evolutionary Consequences, Constraints and Potential of Polyploidy in Plants

    PubMed Central

    Weiss-Schneeweiss, H.; Emadzade, K.; Jang, T.-S.; Schneeweiss, G.M.

    2013-01-01

    Polyploidy, the possession of more than 2 complete genomes, is a major force in plant evolution known to affect the genetic and genomic constitution and the phenotype of an organism, which will have consequences for its ecology and geography as well as for lineage diversification and speciation. In this review, we discuss phylogenetic patterns in the incidence of polyploidy including possible underlying causes, the role of polyploidy for diversification, the effects of polyploidy on geographical and ecological patterns, and putative underlying mechanisms as well as chromosome evolution and evolution of repetitive DNA following polyploidization. Spurred by technological advances, a lot has been learned about these aspects both in model and increasingly also in nonmodel species. Despite this enormous progress, long-standing questions about polyploidy still cannot be unambiguously answered, due to frequently idiosyncratic outcomes and insufficient integration of different organizational levels (from genes to ecology), but likely this will change in the near future. See also the sister article focusing on animals by Choleva and Janko in this themed issue. PMID:23796571

  17. Ecological studies of polyploidy in the 100 years following its discovery

    PubMed Central

    Ramsey, Justin; Ramsey, Tara S.

    2014-01-01

    Polyploidy is a mutation with profound phenotypic consequences and thus hypothesized to have transformative effects in plant ecology. This is most often considered in the context of geographical and environmental distributions—as achieved from divergence of physiological and life-history traits—but may also include species interactions and biological invasion. This paper presents a historical overview of hypotheses and empirical data regarding the ecology of polyploids. Early researchers of polyploidy (1910s–1930s) were geneticists by training but nonetheless savvy to its phenotypic effects, and speculated on the importance of genome duplication to adaptation and crop improvement. Cytogenetic studies in the 1930s–1950s indicated that polyploids are larger (sturdier foliage, thicker stems and taller stature) than diploids while cytogeographic surveys suggested that polyploids and diploids have allopatric or parapatric distributions. Although autopolyploidy was initially regarded as common, influential writings by North American botanists in the 1940s and 1950s argued for the principle role of allopolyploidy; according to this view, genome duplication was significant for providing a broader canvas for hybridization rather than for its phenotypic effects per se. The emphasis on allopolyploidy had a chilling effect on nascent ecological work, in part due to taxonomic challenges posed by interspecific hybridization. Nonetheless, biosystematic efforts over the next few decades (1950s–1970s) laid the foundation for ecological research by documenting cytotype distributions and identifying phenotypic correlates of polyploidy. Rigorous investigation of polyploid ecology was achieved in the 1980s and 1990s by population biologists who leveraged flow cytometry for comparative work in autopolyploid complexes. These efforts revealed multi-faceted ecological and phenotypic differences, some of which may be direct consequences of genome duplication. Several classical

  18. Autophagy sensitivity of neuroendocrine lung tumor cells.

    PubMed

    Hong, Seung-Keun; Kim, Jin-Hwan; Starenki, Dmytro; Park, Jong-In

    2013-12-01

    Neuroendocrine (NE) phenotypes characterize a spectrum of lung tumors, including low-grade typical and intermediate-grade atypical carcinoid, high-grade large-cell NE carcinoma and small cell lung carcinoma. Currently, no effective treatments are available to cure NE lung tumors, demanding identification of biological features specific to these tumors. Here, we report that autophagy has an important role for NE lung tumor cell proliferation and survival. We found that the expression levels of the autophagy marker LC3 are relatively high in a panel of lung tumor cell lines expressing high levels of neuron-specific enolase (NSE), a key NE marker in lung tumors. In response to bafilomycin A1 and chloroquine, NE lung tumor cells exhibited cytotoxicity whereas non-NE lung tumor cells exhibited cytostasis, indicating a distinct role of autophagy for NE lung tumor cell survival. Intriguingly, in certain NE lung tumor cell lines, the levels of processed LC3 (LC3-II) were inversely correlated with AKT activity. When AKT activity was inhibited using AKTi or MK2206, the levels of LC3-II and SQSTM1/p62 were increased. In contrast, torin 1, rapamycin or mTOR knockdown increased p62 levels, suggesting that these two pathways have opposing effects on autophagy in certain NE lung tumors. Moreover, inhibition of one pathway resulted in reduced activity of the other, suggesting that these two pathways crosstalk in the tumors. These results suggest that NE lung tumor cells share a common feature of autophagy and are more sensitive to autophagy inhibition than non-NE lung tumor cells. PMID:24126619

  19. Deformability of Tumor Cells versus Blood Cells

    PubMed Central

    Shaw Bagnall, Josephine; Byun, Sangwon; Begum, Shahinoor; Miyamoto, David T.; Hecht, Vivian C.; Maheswaran, Shyamala; Stott, Shannon L.; Toner, Mehmet; Hynes, Richard O.; Manalis, Scott R.

    2015-01-01

    The potential for circulating tumor cells (CTCs) to elucidate the process of cancer metastasis and inform clinical decision-making has made their isolation of great importance. However, CTCs are rare in the blood, and universal properties with which to identify them remain elusive. As technological advancements have made single-cell deformability measurements increasingly routine, the assessment of physical distinctions between tumor cells and blood cells may provide insight into the feasibility of deformability-based methods for identifying CTCs in patient blood. To this end, we present an initial study assessing deformability differences between tumor cells and blood cells, indicated by the length of time required for them to pass through a microfluidic constriction. Here, we demonstrate that deformability changes in tumor cells that have undergone phenotypic shifts are small compared to differences between tumor cell lines and blood cells. Additionally, in a syngeneic mouse tumor model, cells that are able to exit a tumor and enter circulation are not required to be more deformable than the cells that were first injected into the mouse. However, a limited study of metastatic prostate cancer patients provides evidence that some CTCs may be more mechanically similar to blood cells than to typical tumor cell lines. PMID:26679988

  20. When Bigger Is Better: The Role of Polyploidy in Organogenesis

    PubMed Central

    Orr-Weaver, Terry L.

    2015-01-01

    Defining how organ size is regulated, a process controlled by not only the number of cells but also the size of the cells, is a frontier in developmental biology. Large cells are produced by increasing DNA content or ploidy, a developmental strategy employed throughout the plant and animal kingdoms. The wide-spread use of polyploidy during cell differentiation makes it important to define how this hypertrophy contributes to organogenesis. I discuss here examples from a variety of animals and plants in which polyploidy controls organ size, the size and function of specific tissues within an organ, or the differentiated properties of cells. In addition, I highlight how polyploidy functions in wound healing and tissue regeneration. PMID:25921783

  1. Polyclonal breast cancer metastases arise from collective dissemination of keratin 14-expressing tumor cell clusters

    PubMed Central

    Cheung, Kevin J.; Padmanaban, Veena; Silvestri, Vanesa; Schipper, Koen; Cohen, Joshua D.; Fairchild, Amanda N.; Gorin, Michael A.; Verdone, James E.; Pienta, Kenneth J.; Bader, Joel S.; Ewald, Andrew J.

    2016-01-01

    Recent genomic studies challenge the conventional model that each metastasis must arise from a single tumor cell and instead reveal that metastases can be composed of multiple genetically distinct clones. These intriguing observations raise the question: How do polyclonal metastases emerge from the primary tumor? In this study, we used multicolor lineage tracing to demonstrate that polyclonal seeding by cell clusters is a frequent mechanism in a common mouse model of breast cancer, accounting for >90% of metastases. We directly observed multicolored tumor cell clusters across major stages of metastasis, including collective invasion, local dissemination, intravascular emboli, circulating tumor cell clusters, and micrometastases. Experimentally aggregating tumor cells into clusters induced a >15-fold increase in colony formation ex vivo and a >100-fold increase in metastasis formation in vivo. Intriguingly, locally disseminated clusters, circulating tumor cell clusters, and lung micrometastases frequently expressed the epithelial cytoskeletal protein, keratin 14 (K14). RNA-seq analysis revealed that K14+ cells were enriched for desmosome and hemidesmosome adhesion complex genes, and were depleted for MHC class II genes. Depletion of K14 expression abrogated distant metastases and disrupted expression of multiple metastasis effectors, including Tenascin C (Tnc), Jagged1 (Jag1), and Epiregulin (Ereg). Taken together, our findings reveal K14 as a key regulator of metastasis and establish the concept that K14+ epithelial tumor cell clusters disseminate collectively to colonize distant organs. PMID:26831077

  2. Snail levels control the migration mechanism of mesenchymal tumor cells

    PubMed Central

    BELGIOVINE, CRISTINA; CHIESA, GIULIO; CHIODI, ILARIA; FRAPOLLI, ROBERTA; BONEZZI, KATIUSCIA; TARABOLETTI, GIULIA; D'INCALCI, MAURIZIO; MONDELLO, CHIARA

    2016-01-01

    Cancer cells use two major types of movement: Mesenchymal, which is typical of cells of mesenchymal origin and depends on matrix metalloproteinase (MMP) activity, and amoeboid, which is characteristic of cells with a rounded shape and relies on the activity of Rho-associated kinase (ROCK). The present authors previously demonstrated that, during neoplastic transformation, telomerase-immortalized human fibroblasts (cen3tel cells) acquired a ROCK-dependent/MMP independent mechanism of invasion, mediated by the downregulation of the ROCK cellular inhibitor Round (Rnd)3/RhoE. In the present study, cen3tel transformation was also demonstrated to be paralleled by downregulation of Snail, a major determinant of the mesenchymal movement. To test whether Snail levels could determine the type of movement adopted by mesenchymal tumor cells, Snail was ectopically expressed in tumorigenic cells. It was observed that ectopic Snail did not increase the levels of typical mesenchymal markers, but induced cells to adopt an MMP-dependent mechanism of invasion. In cells expressing ectopic Snail, invasion became sensitive to the MMP inhibitor Ro 28–2653 and insensitive to the ROCK inhibitor Y27632, suggesting that, once induced by Snail, the mesenchymal movement prevails over the amoeboid one. Snail-expressing cells had a more aggressive behavior in vivo, and exhibited increased tumor growth rate and metastatic ability. These results confirm the high plasticity of cancer cells, which can adopt different types of movement in response to changes in the expression of specific genes. Furthermore, the present findings indicate that Rnd3 and Snail are possible regulators of the type of invasion mechanism adopted by mesenchymal tumor cells. PMID:27347214

  3. DAPK loss in colon cancer tumor buds: implications for migration capacity of disseminating tumor cells

    PubMed Central

    Karamitopoulou, Eva; Dawson, Heather; Koelzer, Viktor Hendrik; Agaimy, Abbas; Garreis, Fabian; Söder, Stephan; Laqua, William; Lugli, Alessandro; Hartmann, Arndt; Rau, Tilman T.; Schneider-Stock, Regine

    2015-01-01

    Defining new therapeutic strategies to overcome therapy resistance due to tumor heterogeneity in colon cancer is challenging. One option is to explore the molecular profile of aggressive disseminating tumor cells. The cytoskeleton-associated Death-associated protein kinase (DAPK) is involved in the cross talk between tumor and immune cells at the invasion front of colorectal cancer. Here dedifferentiated tumor cells histologically defined as tumor budding are associated with a high risk of metastasis and poor prognosis. Analyzing samples from 144 colorectal cancer patients we investigated immunhistochemical DAPK expression in different tumor regions such as center, invasion front, and buds. Functional consequences for tumor aggressiveness were studied in a panel of colon tumor cell lines using different migration, wound healing, and invasion assays. DAPK levels were experimentally modified by siRNA transfection and overexpression as well as inhibitor treatments. We found that DAPK expression was reduced towards the invasion front and was nearly absent in tumor buds. Applying the ECIS system with HCT116 and HCT116 stable lentiviral DAPK knock down cells (HCTshDAPK) we identified an important role for DAPK in decreasing the migratory capacity whereas proliferation was not affected. Furthermore, the migration pattern differed with HCTshDAPK cells showing a cluster-like migration of tumor cell groups. DAPK inhibitor treatment revealed that the migration rate was independent of DAPK's catalytic activity. Modulation of DAPK expression level in SW480 and DLD1 colorectal cancer cells significantly influenced wound closure rate. DAPK seems to be a major player that influences the migratory capability of disseminating tumor cells and possibly affects the dynamic interface between pro- and anti-survival factors at the invasion front of colorectal cancer. This interesting and new finding requires further evaluation. PMID:26405175

  4. Targeting tumor cell motility to prevent metastasis

    PubMed Central

    Palmer, Trenis D.; Ashby, William J.; Lewis, John D.; Zijlstra, Andries

    2011-01-01

    Mortality and morbidity in patients with solid tumors invariably results from the disruption of normal biological function caused by disseminating tumor cells. Tumor cell migration is under intense investigation as the underlying cause of cancer metastasis. The need for tumor cell motility in the progression of metastasis has been established experimentally and is supported empirically by basic and clinical research implicating a large collection of migration-related genes. However, there are few clinical interventions designed to specifically target the motility of tumor cells and adjuvant therapy to specifically prevent cancer cell dissemination is severely limited. In an attempt to define motility targets suitable for treating metastasis, we have parsed the molecular determinants of tumor cell motility into five underlying principles including cell autonomous ability, soluble communication, cell-cell adhesion, cell-matrix adhesion, and integrating these determinants of migration on molecular scaffolds. The current challenge is to implement meaningful and sustainable inhibition of metastasis by developing clinically viable disruption of molecular targets that control these fundamental capabilities. PMID:21664937

  5. Energy and Redox Homeostasis in Tumor Cells

    PubMed Central

    de Oliveira, Marcus Fernandes; Amoêdo, Nívea Dias; Rumjanek, Franklin David

    2012-01-01

    Cancer cells display abnormal morphology, chromosomes, and metabolism. This review will focus on the metabolism of tumor cells integrating the available data by way of a functional approach. The first part contains a comprehensive introduction to bioenergetics, mitochondria, and the mechanisms of production and degradation of reactive oxygen species. This will be followed by a discussion on the oxidative metabolism of tumor cells including the morphology, biogenesis, and networking of mitochondria. Tumor cells overexpress proteins that favor fission, such as GTPase dynamin-related protein 1 (Drp1). The interplay between proapoptotic members of the Bcl-2 family that promotes Drp 1-dependent mitochondrial fragmentation and fusogenic antiapoptotic proteins such as Opa-1 will be presented. It will be argued that contrary to the widespread belief that in cancer cells, aerobic glycolysis completely replaces oxidative metabolism, a misrepresentation of Warburg's original results, mitochondria of tumor cells are fully viable and functional. Cancer cells also carry out oxidative metabolism and generally conform to the orthodox model of ATP production maintaining as well an intact electron transport system. Finally, data will be presented indicating that the key to tumor cell survival in an ROS rich environment depends on the overexpression of antioxidant enzymes and high levels of the nonenzymatic antioxidant scavengers. PMID:22693511

  6. Circulating tumor cells exhibit a biologically aggressive cancer phenotype accompanied by selective resistance to chemotherapy.

    PubMed

    Pavese, Janet M; Bergan, Raymond C

    2014-10-01

    With prostate cancer (PCa), circulating tumor cells (CTCs) and disseminated tumor cells (DTCs) portend a poor clinical prognosis. Their unknown biology precludes rational therapeutic design. We demonstrate that CTC and DTC cell lines, established from mice bearing human PCa orthotopic implants, exhibit increased cellular invasion in vitro, increased metastasis in mice, and express increased epithelial to mesenchymal transition biomarkers. Further, they are selectively resistant to growth inhibition by mitoxantrone-like agents. These findings demonstrate that CTC formation is accompanied by phenotypic progression without obligate reversion. Their increased metastatic potential, selective therapeutic resistance, and differential expression of potential therapeutic targets provide a rational basis to test further interventions.

  7. Interaction of MSC with tumor cells.

    PubMed

    Melzer, Catharina; Yang, Yuanyuan; Hass, Ralf

    2016-01-01

    Tumor development and tumor progression is not only determined by the corresponding tumor cells but also by the tumor microenvironment. This includes an orchestrated network of interacting cell types (e.g. immune cells, endothelial cells, fibroblasts, and mesenchymal stroma/stem cells (MSC)) via the extracellular matrix and soluble factors such as cytokines, chemokines, growth factors and various metabolites. Cell populations of the tumor microenvironment can interact directly and indirectly with cancer cells by mutually altering properties and functions of the involved partners. Particularly, mesenchymal stroma/stem cells (MSC) play an important role during carcinogenesis exhibiting different types of intercellular communication. Accordingly, this work focusses on diverse mechanisms of interaction between MSC and cancer cells. Moreover, some functional changes and consequences for both cell types are summarized which can eventually result in the establishment of a carcinoma stem cell niche (CSCN) or the generation of new tumor cell populations by MSC-tumor cell fusion. PMID:27608835

  8. Imaging Tumor Cell Movement In Vivo

    PubMed Central

    Entenberg, David; Kedrin, Dmitriy; Wyckoff, Jeffrey; Sahai, Erik; Condeelis, John; Segall, Jeffrey E.

    2013-01-01

    This unit describes the methods that we have been developing for analyzing tumor cell motility in mouse and rat models of breast cancer metastasis. Rodents are commonly used both to provide a mammalian system for studying human tumor cells (as xenografts in immunocompromised mice) as well as for following the development of tumors from a specific tissue type in transgenic lines. The Basic Protocol in this unit describes the standard methods used for generation of mammary tumors and imaging them. Additional protocols for labeling macrophages, blood vessel imaging, and image analysis are also included. PMID:23456602

  9. Case study of the morphologic variation of circulating tumor cells.

    PubMed

    Marrinucci, Dena; Bethel, Kelly; Bruce, Richard H; Curry, Douglas N; Hsieh, Ben; Humphrey, Mark; Krivacic, Robert T; Kroener, Joan; Kroener, Lindsay; Ladanyi, Andras; Lazarus, Nicole H; Nieva, Jorge; Kuhn, Peter

    2007-03-01

    We report a detailed cytomorphologic evaluation of the circulating component of widely metastatic breast carcinoma. A previously healthy 38-year-old woman was diagnosed with breast cancer. Wide local excision revealed a 1.7-cm infiltrating ductal adenocarcinoma, BSR score 7/9 with angiolymphatic invasion, and 4/20 lymph nodes positive for carcinoma. Five years later, a bone marrow biopsy revealed involvement of bone marrow by metastatic breast carcinoma, and shortly thereafter, metastases were identified in the liver and lung hilum. She enrolled in a clinical investigation for the detection of circulating tumor cells (CTCs) in breast carcinoma. A total of 659 CTCs were identified in a 10-mL blood sample using an immunofluorescent protocol targeting cytokeratins and detected using fiber-optic array scanning technology. The detected CTCs were subsequently stained with a Wright-Giemsa stain, and representative cells were evaluated in detail by light microscopy for morphologic evaluation. We find that the patient's CTCs exhibit a high degree of pleomorphism including CTCs with high and low nuclear-to-cytoplasmic ratios along with CTCs exhibiting early and late apoptotic changes. In addition, in comparison with her tumor cells in other sites, the full morphologic spectrum of cancer cells present in primary and metastatic tumor is also present in peripheral blood circulation. PMID:17188328

  10. Circulating tumor cells as promising novel biomarkers in solid cancers.

    PubMed

    Lianidou, Evi S; Strati, Areti; Markou, Athina

    2014-06-01

    The presence of circulating tumor cells (CTCs) in peripheral blood can serve as a "liquid biopsy" approach and has thus emerged lately as one of the hottest fields in cancer research. CTCs can be isolated from blood in a non-invasive approach, and can be used to follow patients over time since these cells can provide significant information for a better understanding of tumor biology and tumor cell dissemination. CTC molecular characterization offers the unique potential to better understand the biology of metastasis and resistance to established therapies, and analysis of these cells presents a promising field for both advanced and early-stage patients. CTC detection, enumeration, and molecular characterization are very challenging since CTCs are rare, and the amount of available sample is very limited. Since detection of CTCs has been shown to be of considerable utility in the clinical management of patients with solid cancers, various analytical systems for their isolation and detection have been developed. New areas of research are directed towards developing novel assays for single-CTC isolation and molecular characterization. The clinical significance of CTCs has been evaluated in many types of solid cancers, and the CTC enumeration test in metastatic breast, colorectal, and prostate cancer was cleared by the FDA almost a decade ago. This review is mainly focused on the clinical potential of CTCs as novel biomarkers in 10 different types of solid cancers: breast, ovarian, prostate, lung, colorectal, hepatocellular carcinoma, pancreatic, head and neck, bladder cancer and melanoma.

  11. Mechanical response of tumor cells flowing through a microfluidic capillary

    NASA Astrophysics Data System (ADS)

    Khan, Zeina S.; Kamyabi, Nabiollah; Hussain, Fazle; Vanapalli, Siva A.

    2014-03-01

    Circulating tumor cells, the primary cause of cancer metastasis, are transported throughout the body to distant organs by blood flow. Despite the importance of cell transport and deformability in the vasculature for cancer metastasis, quantitative understanding of the hydrodynamic interactions between the cells and the blood vessel walls is lacking. Using a model microfluidic capillary of rectangular cross-section with an on-chip manometer coupled with high speed video imaging, we quantitatively investigate the hydrodynamic behavior via the cell excess pressure drop. By characterizing our device with simple model systems including viscous drops and soft elastic particles, we find that the excess pressure drop shows no apparent dependence on elastic modulus or interfacial tension, but depends significantly on internal viscosity for moderate confinements and shear stresses within the physiological range of 1-10 Pa. This suggests that the metastatic potential of circulating cells can be characterized by the effective viscosity. We test this hypothesis with several tumor cell lines and find that the effective cell viscosity determined from excess pressure drop measurements can be used to differentiate highly from lowly invasive cells.

  12. Circulating tumor cells in colorectal cancer patients.

    PubMed

    Torino, Francesco; Bonmassar, Enzo; Bonmassar, Laura; De Vecchis, Liana; Barnabei, Agnese; Zuppi, Cecilia; Capoluongo, Ettore; Aquino, Angelo

    2013-11-01

    The availability of sensitive methods has allowed the detailed study of circulating tumor cells only recently. Evolving evidence support the prognostic and predictive role of these cells in patients affected by several solid tumors, including colorectal cancer. Ongoing studies are aimed at confirming that the molecular characterization of circulating tumor cells in peripheral blood and in bone marrow of patients is a powerful tool to improve the patient risk-stratification, to monitor activity of the drugs, to develop more appropriate targeted therapies and tailored treatments. In parallel, results from these correlative studies promise to gain a better biological understanding of the metastatic process. The clinical utility of the detection of circulating tumor cells in patients affected by colorectal cancer is still hampered by a number of specific hurdles. Improvement in sensitivity and specificity of the available methods of detection, standardization of these methods and functional characterization of circulating tumor cells in well designed and statistically well powered studies are the key steps to reach these ambitious objectives in colorectal cancer patients as well.

  13. Evolution of cooperation among tumor cells.

    PubMed

    Axelrod, Robert; Axelrod, David E; Pienta, Kenneth J

    2006-09-01

    The evolution of cooperation has a well established theoretical framework based on game theory. This approach has made valuable contributions to a wide variety of disciplines, including political science, economics, and evolutionary biology. Existing cancer theory suggests that individual clones of cancer cells evolve independently from one another, acquiring all of the genetic traits or hallmarks necessary to form a malignant tumor. It is also now recognized that tumors are heterotypic, with cancer cells interacting with normal stromal cells within the tissue microenvironment, including endothelial, stromal, and nerve cells. This tumor cell-stromal cell interaction in itself is a form of commensalism, because it has been demonstrated that these nonmalignant cells support and even enable tumor growth. Here, we add to this theory by regarding tumor cells as game players whose interactions help to determine their Darwinian fitness. We marshal evidence that tumor cells overcome certain host defenses by means of diffusible products. Our original contribution is to raise the possibility that two nearby cells can protect each other from a set of host defenses that neither could survive alone. Cooperation can evolve as by-product mutualism among genetically diverse tumor cells. Our hypothesis supplements, but does not supplant, the traditional view of carcinogenesis in which one clonal population of cells develops all of the necessary genetic traits independently to form a tumor. Cooperation through the sharing of diffusible products raises new questions about tumorigenesis and has implications for understanding observed phenomena, designing new experiments, and developing new therapeutic approaches.

  14. Nanotechnology for enrichment and detection of circulating tumor cells

    PubMed Central

    Bhana, Saheel; Wang, Yongmei; Huang, Xiaohua

    2015-01-01

    Circulating tumor cells (CTCs) are a hallmark of invasive behavior of cancer, responsible for the development of metastasis. Their detection and analysis have significant impacts in cancer biology and clinical practice. However, CTCs are rare events and contain heterogeneous subpopulations, requiring highly sensitive and specific techniques to identify and capture CTCs with high efficiency. Nanotechnology shows strong promises for CTC enrichment and detection owning to the unique structural and functional properties of nanoscale materials. In this review, we discuss the CTC enrichment and detection technologies based on a variety of functional nanosystems and nanostructured substrates, with the goal to highlight the role of nanotechnology in the advancement of basic and clinical CTC research. PMID:26139129

  15. [Circulating tumor cells in head and neck cancer].

    PubMed

    Guntinas-Lichius, O; Pachmann, K

    2015-06-01

    Circulating tumor cells are defined as tumor cells which are circulating in the peripheral blood of the cancer patient. While several large studies have investigated the role of circulating tumor cells in other solid tumors, the importance of these tumor cells in patients with head and neck cancer was turned into the focus not until the recent years. In other solid tumor the presence of circulating tumor cells often seems to be a negative prognostic marker and seems to be a marker for therapy response. The present article wants to give an overview about the knowledge on circulating tumor cells and their clinical relevance in head and neck cancer. The methodology to detect circulating tumor cells will be critically reflected. The future potential of the detection of circulating tumor cells in head and neck cancer patients will be discussed.

  16. Anatomical alterations due to polyploidy in cassava, Manihot esculenta Crantz.

    PubMed

    Nassar, Nagib M A; Graciano-Ribeiro, D; Fernandes, S D C; Araujo, P C

    2008-01-01

    Information on anatomical structure is needed by breeders working on improvement for drought tolerance. For studying the effect of polyploidy on cassava anatomy and its significance to tolerance to drought, we induced a polyploidy type of a selected clone (UnB 530) by applying an aqueous solution of 0.2% colchicine on lateral buds for a period of 12 h. The stem identified as tetraploid was propagated to produce the whole plant. Free-hand cross-sections of the median portion between stem internodes were made. They were clarified using 50% sodium hypochlorite solution, stained with 1% safranin-alcian blue, passed through an ethanol series and butyl acetate and mounted in synthetic resin. The tetraploid type showed more prismatic and druse crystals in the cortical parenchyma, and its pericycle fibers had thicker walls. The secondary xylem of tetraploid types was wider than diploid ones, having thinner walls and less starch. PMID:18551393

  17. Polyploidy alters advertisement call structure in gray treefrogs.

    PubMed Central

    Keller, M. J.; Gerhardt, H. C.

    2001-01-01

    Whole-genome duplication is believed to have played a significant role in the early evolution and diversification of vertebrate animals. The establishment of newly arisen polyploid lineages of sexually reproducing animals requires assortative mating between polyploids. Here, we show that genome duplication can directly alter a phenotypic trait mediating mate choice in the absence of genotypic change. Our results suggest that the direct effect of polyploidy on behaviour is a consequence of increased cell size. PMID:11270429

  18. High frequency of tumor cells with nuclear Egr-1 protein expression in human bladder cancer is associated with disease progression

    PubMed Central

    2009-01-01

    Background Egr-1 (early growth response-1 transcription factor) has been proposed to be involved in invasion and metastasis processes of human bladder cancer, but Egr-1 protein expression levels in human bladder cancer have not been investigated. In the present study we investigated the expression levels of Egr-1 protein in early stages of human bladder cancer and correlated it to later progression. Methods Expression of Egr-1 protein in human bladder cancer was examined by immunohistochemistry, on a tissue microarray constructed from tumors from 289 patients with non-muscle invasive urothelial bladder cancer. Results The frequency of tumor cells with nuclear Egr-1 immunolabelling correlated to bladder cancer stage, grade and to later progression to muscle-invasive bladder cancer (T2-4). Stage T1 tumors exhibited significantly higher frequencies of tumor cells with nuclear Egr-1 immunolabelling than Ta tumors (P = 0.001). Furthermore, Kaplan-Meier survival analysis showed that a high frequency of tumor cells with nuclear Egr-1 immunolabelling was significantly associated with a higher risk of progression to stage T2-4 (log-rank test, P = 0.035). Tumor cells with nuclear Egr-1 immunolabelling were found to localize at the tumor front in some of the tumor biopsies. Conclusion The results from this study support a potential involvement of Egr-1 in the progression from non-muscle invasive bladder cancers to muscle invasive bladder cancer. PMID:19878561

  19. Determination of EGFR mutations in single cells microdissected from enriched lung tumor cells in peripheral blood.

    PubMed

    Ran, Ran; Li, Longyun; Wang, Mengzhao; Wang, Shulan; Zheng, Zhi; Lin, Peter Ping

    2013-09-01

    A minimally invasive and repeatable approach for real-time epidermal growth factor receptor (EGFR) mutation surveillance would be highly beneficial for individualized therapy of late stage lung cancer patients whose surgical specimens are often not available. We aim to develop a viable method to detect EGFR mutations in single circulating tumor cells (CTCs). Using a model CTC system of spiked tumor cells in whole blood, we evaluated EGFR mutation determination in single tumor cells enriched from blood. We used magnetic beads labeled with antibody against leukocyte surface antigens to deplete leukocytes and enrich native CTCs independent of epithelial marker expression level. We then used laser cell microdissection (LCM) to isolate individual CTCs, followed by whole-genome amplification of the DNA for exon 19 microdeletion, L858R and T790M mutation detection by PCR sequencing. EGFR mutations were successfully measured in individual spiked tumor cells enriched from 7.5 ml whole blood. Whole-genome amplification provided sufficient DNA for mutation determination at multiple sites. Ninety-five percent of the single CTCs microdissected by LCM (19/20) yielded PCR amplicons for at least one of the three mutation sites. The amplification success rates were 55 % (11/20) for exon 19 deletion, 45 % (9/20) for T790M, and 85 % (17/20) for L858R. Sequencing of the amplicons showed allele dropout in the amplification reactions, but mutations were correctly identified in 80 % of the amplicons. EGFR mutation determination from single captured tumor cells from blood is feasible with the approach described here. However, to overcome allele dropout and to obtain reliable information about the tumor's EGFR status, multiple individual tumor cells should be assayed. PMID:23828210

  20. HAMLET (human alpha-lactalbumin made lethal to tumor cells) triggers autophagic tumor cell death.

    PubMed

    Aits, Sonja; Gustafsson, Lotta; Hallgren, Oskar; Brest, Patrick; Gustafsson, Mattias; Trulsson, Maria; Mossberg, Ann-Kristin; Simon, Hans-Uwe; Mograbi, Baharia; Svanborg, Catharina

    2009-03-01

    HAMLET, a complex of partially unfolded alpha-lactalbumin and oleic acid, kills a wide range of tumor cells. Here we propose that HAMLET causes macroautophagy in tumor cells and that this contributes to their death. Cell death was accompanied by mitochondrial damage and a reduction in the level of active mTOR and HAMLET triggered extensive cytoplasmic vacuolization and the formation of double-membrane-enclosed vesicles typical of macroautophagy. In addition, HAMLET caused a change from uniform (LC3-I) to granular (LC3-II) staining in LC3-GFP-transfected cells reflecting LC3 translocation during macroautophagy, and this was blocked by the macroautophagy inhibitor 3-methyladenine. HAMLET also caused accumulation of LC3-II detected by Western blot when lysosomal degradation was inhibited suggesting that HAMLET caused an increase in autophagic flux. To determine if macroautophagy contributed to cell death, we used RNA interference against Beclin-1 and Atg5. Suppression of Beclin-1 and Atg5 improved the survival of HAMLET-treated tumor cells and inhibited the increase in granular LC3-GFP staining. The results show that HAMLET triggers macroautophagy in tumor cells and suggest that macroautophagy contributes to HAMLET-induced tumor cell death.

  1. Regulation of vimentin by SIP1 in human epithelial breast tumor cells.

    PubMed

    Bindels, S; Mestdagt, M; Vandewalle, C; Jacobs, N; Volders, L; Noël, A; van Roy, F; Berx, G; Foidart, J-M; Gilles, C

    2006-08-17

    The expression of Smad interacting protein-1 (SIP1; ZEB2) and the de novo expression of vimentin are frequently involved in epithelial-to-mesenchymal transitions (EMTs) under both normal and pathological conditions. In the present study, we investigated the potential role of SIP1 in the regulation of vimentin during the EMT associated with breast tumor cell migration and invasion. Examining several breast tumor cell lines displaying various degrees of invasiveness, we found SIP1 and vimentin expression only in invasive cell lines. Also, using a model of cell migration with human mammary MCF10A cells, we showed that SIP1 is induced specifically in vimentin-positive migratory cells. Furthermore, transfection of SIP1 cDNA in MCF10A cells increased their vimentin expression both at the mRNA and protein levels and enhanced their migratory abilities in Boyden Chamber assays. Inversely, inhibition of SIP1 expression by RNAi strategies in BT-549 cells and MCF10A cells decreased vimentin expression. We also showed that SIP1 transfection did not activate the TOP-FLASH reporter system, suggesting that the beta-catenin/TCF pathway is not implicated in the regulation of vimentin by SIP1. Our results therefore implicate SIP1 in the regulation of vimentin observed in the EMT associated with breast tumor cell migration, a pathway that may contribute to the metastatic progression of breast cancer.

  2. Electric Field Analysis of Breast Tumor Cells

    PubMed Central

    Sree, V. Gowri; Udayakumar, K.; Sundararajan, R.

    2011-01-01

    An attractive alternative treatment for malignant tumors that are refractive to conventional therapies, such as surgery, radiation, and chemotherapy, is electrical-pulse-mediated drug delivery. Electric field distribution of tissue/tumor is important for effective treatment of tissues. This paper deals with the electric field distribution study of a tissue model using MAXWELL 3D Simulator. Our results indicate that tumor tissue had lower electric field strength compared to normal cells, which makes them susceptible to electrical-pulse-mediated drug delivery. This difference could be due to the altered properties of tumor cells compared to normal cells, and our results corroborate this. PMID:22295214

  3. [Cancer stemness and circulating tumor cells].

    PubMed

    Saito, Tomoko; Mimori, Koshi

    2015-05-01

    The principle concept of cancer stem cells (CSCs) giving rise to the carcinogenesis, relapse or metastasis of malignancy is broadly recognized. On the other hand, circulating tumor cells (CTCs) also plays important roles in relapse or metastasis of malignancy, and there has been much focused on the association between CSCs and CTCs in cancer cases. The technical innovations for detection of CTCs enabled us to unveil the nature of CTCs. We now realize that CTCs isolated by cell surface antibodies, such as DCLK1, LGR5 indicated CSC properties, and CTCs with epitherial-mesenchymal transition(EMT) phenotype showed characteristics of CSCs. PMID:25985635

  4. Leptin and Adiponectin: new players in the field of tumor cell and leukocyte migration

    PubMed Central

    2009-01-01

    Adipose tissue is no longer considered to be solely an energy storage, but exerts important endocrine functions, which are primarily mediated by a network of various soluble factors derived from fat cells, called adipocytokines. In addition to their responsibility to influence energy homeostasis, new studies have identified important pathways linking metabolism with the immune system, and demonstrating a modulatory role of adipocytokines in immune function. Additionally, epidemiological studies underline that obesity represents a significant risk factor for the development of cancer, although the exact mechanism of this relationship remains to be determined. Whereas a possible influence of adipocytokines on the proliferation of tumor cells is already known, new evidence has come to light elucidating a modulatory role of this signaling substances in the regulation of migration of leukocytes and tumor cells. The migration of leukocytes is a key feature to fight cancer cells, whereas the locomotion of tumor cells is a prerequisite for tumor formation and metastasis. We herein review the latest tumor biological findings on the role of the most prominent adipocytokines leptin and adiponectin, which are secreted by fat cells, and which are involved in leukocyte migration, tumor growth, invasion and metastasis. This review thus accentuates the complex, interactive involvement of adipocytokines in the regulation of migration of both leukocytes and tumor cells, and gives an insight in the underlying molecular mechanisms. PMID:20030801

  5. Second-harmonic generation scattering directionality predicts tumor cell motility in collagen gels.

    PubMed

    Burke, Kathleen A; Dawes, Ryan P; Cheema, Mehar K; Van Hove, Amy; Benoit, Danielle S W; Perry, Seth W; Brown, Edward

    2015-05-01

    Second-harmonic generation (SHG) allows for the analysis of tumor collagen structural changes throughout metastatic progression. SHG directionality, measured through the ratio of the forward-propagating to backward-propagating signal (F/B ratio), is affected by collagen fibril diameter, spacing, and disorder of fibril packing within a fiber. As tumors progress, these parameters evolve, producing concurrent changes in F/B. It has been recently shown that the F/B of highly metastatic invasive ductal carcinoma (IDC) breast tumors is significantly different from less metastatic tumors. This suggests a possible relationship between the microstructure of collagen, as measured by the F/B, and the ability of tumor cells to locomote through that collagen. Utilizing in vitro collagen gels of different F/B ratios, we explored the relationship between collagen microstructure and motility of tumor cells in a “clean” environment, free of the myriad cells, and signals found in in vivo. We found a significant relationship between F/B and the total distance traveled by the tumor cell, as well as both the average and maximum velocities of the cells. Consequently, one possible mechanism underlying the observed relationship between tumor F/B and metastatic output in IDC patient samples is a direct influence of collagen structure on tumor cell motility. PMID:25625899

  6. Second-harmonic generation scattering directionality predicts tumor cell motility in collagen gels

    NASA Astrophysics Data System (ADS)

    Burke, Kathleen A.; Dawes, Ryan P.; Cheema, Mehar K.; Van Hove, Amy; Benoit, Danielle S. W.; Perry, Seth W.; Brown, Edward

    2015-05-01

    Second-harmonic generation (SHG) allows for the analysis of tumor collagen structural changes throughout metastatic progression. SHG directionality, measured through the ratio of the forward-propagating to backward-propagating signal (F/B ratio), is affected by collagen fibril diameter, spacing, and disorder of fibril packing within a fiber. As tumors progress, these parameters evolve, producing concurrent changes in F/B. It has been recently shown that the F/B of highly metastatic invasive ductal carcinoma (IDC) breast tumors is significantly different from less metastatic tumors. This suggests a possible relationship between the microstructure of collagen, as measured by the F/B, and the ability of tumor cells to locomote through that collagen. Utilizing in vitro collagen gels of different F/B ratios, we explored the relationship between collagen microstructure and motility of tumor cells in a "clean" environment, free of the myriad cells, and signals found in in vivo. We found a significant relationship between F/B and the total distance traveled by the tumor cell, as well as both the average and maximum velocities of the cells. Consequently, one possible mechanism underlying the observed relationship between tumor F/B and metastatic output in IDC patient samples is a direct influence of collagen structure on tumor cell motility.

  7. Circulating Tumor Cells Measurements in Hepatocellular Carcinoma

    PubMed Central

    Chiappini, Franck

    2012-01-01

    Liver cancer is the fifth most common cancer in men and the seventh in women. During the past 20 years, the incidence of HCC has tripled while the 5-year survival rate has remained below 12%. The presence of circulating tumor cells (CTC) reflects the aggressiveness nature of a tumor. Many attempts have been made to develop assays that reliably detect and enumerate the CTC during the development of the HCC. In this case, the challenges are (1) there are few markers specific to the HCC (tumor cells versus nontumor cells) and (2) they can be used to quantify the number of CTC in the bloodstream. Another technical challenge consists of finding few CTC mixed with million leukocytes and billion erythrocytes. CTC detection and identification can be used to estimate prognosis and may serve as an early marker to assess antitumor activity of treatment. CTC can also be used to predict progression-free survival and overall survival. CTC are an interesting source of biological information in order to understand dissemination, drug resistance, and treatment-induced cell death. Our aim is to review and analyze the different new methods existing to detect, enumerate, and characterize the CTC in the peripheral circulation of patients with HCC. PMID:22690340

  8. Transcapillary Trafficking of Clustered Circulating Tumor Cells

    NASA Astrophysics Data System (ADS)

    Storey, Brian; Au, Sam; Chen, Yeng-Long; Sarioglu, Fatih; Javaid, Sarah; Haber, Daniel; Maheswaran, Shyamala; Stott, Shannon; Toner, Mehmet

    2015-11-01

    Aggregates of circulating tumor cells (CTC-clusters) are known to be more metastatic than equal numbers of singlet circulating tumor cells. Yet the mechanisms responsible for CTC-cluster dissemination and tumor seeding are still largely unknown. Without direct experimental evidence, it was assumed that because of their size, CTC-clusters would occlude and rupture capillaries. In this work, we have challenged this assumption by investigating the transit of CTC-clusters through microfluidic capillary constrictions under physiological pressures. Remarkably, cancer cell aggregates containing 2-20 cells were observed to successfully traverse constrictions 5-10 microns with over 90% efficiency. Clusters rapidly and reversibly reorganized into chain-like geometries to pass through constrictions in single file. This observation was verified by computational simulation of clusters modeled with physiological cell-cell interaction energies. Hydrodynamic analysis suggested that CTC-clusters were able to pass narrow constrictions by acting as individual cells in series, not as cohesive units. Upon exiting constrictions, clusters remained viable, proliferative and rapidly returned to `typical' cluster morphologies.

  9. Differential effects of serine proteases on the migration of normal and tumor cells: implications for tumor microenvironment.

    PubMed

    Elzer, Kirsten L; Heitzman, Deborah A; Chernin, Mitchell I; Novak, Josef F

    2008-12-01

    The supporting role of proteases in tumor progression and invasion is well known; however, the use of proteases as therapeutic agents has also been demonstrated. In this article, the authors report on the differential effects of exogenous serine proteases on the motility of tumor and normal cells. The treatment of normal and tumor cells with a single dose of pancreatic serine proteases, trypsin (TR) and chymotrypsin (CH), leads to a concentration-dependent response by cells, first accelerating and then slowing mobility. Tumor cells are 10 to 20 times more sensitive to exogenous TR/CH, suggesting that a single dose of proteases may cause discordant movements of normal and tumor cells within the tumor environment. The inhibitory effects of TR on cell motility are contradicted by thrombin (TH), particularly in the regulation of normal cells' migration. The purpose of this investigation was to ascertain the role of protease-activated receptors (PARs) in terms of normal and tumor cell motility. Duplicate treatments with proteases resulted in diminished mobility of both normal and tumor cells. Repeated application of TR and TH in 1-hour treatment intervals initially desensitizes cell surface PARs. However, cell surface PARs reappear regardless of subsequent protease treatments in both normal and tumor cells. The resensitization process is retarded in tumor cells when compared with normal cells. This is evidenced by lower expression of PARs as well as by their relocalization at the tumor cell surfaces. Under these conditions, normal cells remain responsive to exogenous proteases in terms of cell motility. Exogenous proteases do not modulate motility of repeatedly stimulated tumor cells, and consequently, the migration of tumor cells appears disconnected from the PAR signaling pathways. The use of activating peptides in lieu of the cognate proteases for a given PAR system indicated that proteases may act through additional targets not regulated by PAR signaling. We

  10. Polyploidy-associated genome modifications during land plant evolution

    PubMed Central

    Jiao, Yuannian; Paterson, Andrew H.

    2014-01-01

    The occurrence of polyploidy in land plant evolution has led to an acceleration of genome modifications relative to other crown eukaryotes and is correlated with key innovations in plant evolution. Extensive genome resources provide for relating genomic changes to the origins of novel morphological and physiological features of plants. Ancestral gene contents for key nodes of the plant family tree are inferred. Pervasive polyploidy in angiosperms appears likely to be the major factor generating novel angiosperm genes and expanding some gene families. However, most gene families lose most duplicated copies in a quasi-neutral process, and a few families are actively selected for single-copy status. One of the great challenges of evolutionary genomics is to link genome modifications to speciation, diversification and the morphological and/or physiological innovations that collectively compose biodiversity. Rapid accumulation of genomic data and its ongoing investigation may greatly improve the resolution at which evolutionary approaches can contribute to the identification of specific genes responsible for particular innovations. The resulting, more ‘particulate’ understanding of plant evolution, may elevate to a new level fundamental knowledge of botanical diversity, including economically important traits in the crop plants that sustain humanity. PMID:24958928

  11. Quantitative tracking of tumor cells in phase-contrast microscopy exploiting halo artifact pattern

    NASA Astrophysics Data System (ADS)

    Kang, Mi-Sun; Song, Soo-Min; Lee, Hana; Kim, Myoung-Hee

    2012-03-01

    Tumor cell morphology is closely related to its invasiveness characteristics and migratory behaviors. An invasive tumor cell has a highly irregular shape, whereas a spherical cell is non-metastatic. Thus, quantitative analysis of cell features is crucial to determine tumor malignancy or to test the efficacy of anticancer treatment. We use phase-contrast microscopy to analyze single cell morphology and to monitor its change because it enables observation of long-term activity of living cells without photobleaching and phototoxicity, which is common in other fluorescence-labeled microscopy. Despite this advantage, there are image-level drawbacks to phase-contrast microscopy, such as local light effect and contrast interference ring, among others. Thus, we first applied a local filter to compensate for non-uniform illumination. Then, we used intensity distribution information to detect the cell boundary. In phase-contrast microscopy images, the cell normally appears as a dark region surrounded by a bright halo. As the halo artifact around the cell body is minimal and has an asymmetric diffusion pattern, we calculated the cross-sectional plane that intersected the center of each cell and was orthogonal to the first principal axis. Then, we extracted the dark cell region by level set. However, a dense population of cultured cells still rendered single-cell analysis difficult. Finally, we measured roundness and size to classify tumor cells into malignant and benign groups. We validated segmentation accuracy by comparing our findings with manually obtained results.

  12. The Carbamoylmannose Moiety of Bleomycin Mediates Selective Tumor Cell Targeting

    PubMed Central

    2015-01-01

    Recently, we reported that both bleomycin (BLM) and its disaccharide, conjugated to the cyanine dye Cy5**, bound selectively to cancer cells. Thus, the disaccharide moiety alone recapitulates the tumor cell targeting properties of BLM. Here, we demonstrate that the conjugate of the BLM carbamoylmannose moiety with Cy5** showed tumor cell selective binding and also enhanced cellular uptake in most cancer cell lines. The carbamoyl functionality was required for tumor cell targeting. A dye conjugate prepared from a trivalent cluster of carbamoylmannose exhibited levels of tumor cell binding and internalization significantly greater than those of the simple carbamoylmannose–dye conjugate, consistent with a possible multivalent receptor. PMID:24811347

  13. Circulating tumor cells: utopia or reality?

    PubMed

    Conteduca, Vincenza; Zamarchi, Rita; Rossi, Elisabetta; Condelli, Valentina; Troiani, Laura; Aieta, Michele

    2013-09-01

    Circulating tumor cells (CTCs) could be considered a sign of tumor aggressiveness, but highly sensitive and specific methods of CTC detection are necessary owing to the rarity and heterogeneity of CTCs in peripheral blood. This review summarizes recent studies on tumor biology, with particular attention to the metastatic cascade, and the molecular characterization and clinical significance of CTCs. Recent technological approaches to enrich and detect these cells and challenges of CTCs for individualized cancer treatment are also discussed. This review also provides an insight into the positive and negative features of the future potential applications of CTC detection, which sometimes remains still a 'utopia', but its actual utility remains among the fastest growing research fields in oncology. PMID:23980681

  14. Circulating tumor cells: utopia or reality?

    PubMed

    Conteduca, Vincenza; Zamarchi, Rita; Rossi, Elisabetta; Condelli, Valentina; Troiani, Laura; Aieta, Michele

    2013-09-01

    Circulating tumor cells (CTCs) could be considered a sign of tumor aggressiveness, but highly sensitive and specific methods of CTC detection are necessary owing to the rarity and heterogeneity of CTCs in peripheral blood. This review summarizes recent studies on tumor biology, with particular attention to the metastatic cascade, and the molecular characterization and clinical significance of CTCs. Recent technological approaches to enrich and detect these cells and challenges of CTCs for individualized cancer treatment are also discussed. This review also provides an insight into the positive and negative features of the future potential applications of CTC detection, which sometimes remains still a 'utopia', but its actual utility remains among the fastest growing research fields in oncology.

  15. Acoustic separation of circulating tumor cells.

    PubMed

    Li, Peng; Mao, Zhangming; Peng, Zhangli; Zhou, Lanlan; Chen, Yuchao; Huang, Po-Hsun; Truica, Cristina I; Drabick, Joseph J; El-Deiry, Wafik S; Dao, Ming; Suresh, Subra; Huang, Tony Jun

    2015-04-21

    Circulating tumor cells (CTCs) are important targets for cancer biology studies. To further elucidate the role of CTCs in cancer metastasis and prognosis, effective methods for isolating extremely rare tumor cells from peripheral blood must be developed. Acoustic-based methods, which are known to preserve the integrity, functionality, and viability of biological cells using label-free and contact-free sorting, have thus far not been successfully developed to isolate rare CTCs using clinical samples from cancer patients owing to technical constraints, insufficient throughput, and lack of long-term device stability. In this work, we demonstrate the development of an acoustic-based microfluidic device that is capable of high-throughput separation of CTCs from peripheral blood samples obtained from cancer patients. Our method uses tilted-angle standing surface acoustic waves. Parametric numerical simulations were performed to design optimum device geometry, tilt angle, and cell throughput that is more than 20 times higher than previously possible for such devices. We first validated the capability of this device by successfully separating low concentrations (∼100 cells/mL) of a variety of cancer cells from cell culture lines from WBCs with a recovery rate better than 83%. We then demonstrated the isolation of CTCs in blood samples obtained from patients with breast cancer. Our acoustic-based separation method thus offers the potential to serve as an invaluable supplemental tool in cancer research, diagnostics, drug efficacy assessment, and therapeutics owing to its excellent biocompatibility, simple design, and label-free automated operation while offering the capability to isolate rare CTCs in a viable state.

  16. Acoustic separation of circulating tumor cells

    PubMed Central

    Li, Peng; Mao, Zhangming; Peng, Zhangli; Zhou, Lanlan; Chen, Yuchao; Huang, Po-Hsun; Truica, Cristina I.; Drabick, Joseph J.; El-Deiry, Wafik S.; Dao, Ming; Suresh, Subra; Huang, Tony Jun

    2015-01-01

    Circulating tumor cells (CTCs) are important targets for cancer biology studies. To further elucidate the role of CTCs in cancer metastasis and prognosis, effective methods for isolating extremely rare tumor cells from peripheral blood must be developed. Acoustic-based methods, which are known to preserve the integrity, functionality, and viability of biological cells using label-free and contact-free sorting, have thus far not been successfully developed to isolate rare CTCs using clinical samples from cancer patients owing to technical constraints, insufficient throughput, and lack of long-term device stability. In this work, we demonstrate the development of an acoustic-based microfluidic device that is capable of high-throughput separation of CTCs from peripheral blood samples obtained from cancer patients. Our method uses tilted-angle standing surface acoustic waves. Parametric numerical simulations were performed to design optimum device geometry, tilt angle, and cell throughput that is more than 20 times higher than previously possible for such devices. We first validated the capability of this device by successfully separating low concentrations (∼100 cells/mL) of a variety of cancer cells from cell culture lines from WBCs with a recovery rate better than 83%. We then demonstrated the isolation of CTCs in blood samples obtained from patients with breast cancer. Our acoustic-based separation method thus offers the potential to serve as an invaluable supplemental tool in cancer research, diagnostics, drug efficacy assessment, and therapeutics owing to its excellent biocompatibility, simple design, and label-free automated operation while offering the capability to isolate rare CTCs in a viable state. PMID:25848039

  17. Acoustic separation of circulating tumor cells.

    PubMed

    Li, Peng; Mao, Zhangming; Peng, Zhangli; Zhou, Lanlan; Chen, Yuchao; Huang, Po-Hsun; Truica, Cristina I; Drabick, Joseph J; El-Deiry, Wafik S; Dao, Ming; Suresh, Subra; Huang, Tony Jun

    2015-04-21

    Circulating tumor cells (CTCs) are important targets for cancer biology studies. To further elucidate the role of CTCs in cancer metastasis and prognosis, effective methods for isolating extremely rare tumor cells from peripheral blood must be developed. Acoustic-based methods, which are known to preserve the integrity, functionality, and viability of biological cells using label-free and contact-free sorting, have thus far not been successfully developed to isolate rare CTCs using clinical samples from cancer patients owing to technical constraints, insufficient throughput, and lack of long-term device stability. In this work, we demonstrate the development of an acoustic-based microfluidic device that is capable of high-throughput separation of CTCs from peripheral blood samples obtained from cancer patients. Our method uses tilted-angle standing surface acoustic waves. Parametric numerical simulations were performed to design optimum device geometry, tilt angle, and cell throughput that is more than 20 times higher than previously possible for such devices. We first validated the capability of this device by successfully separating low concentrations (∼100 cells/mL) of a variety of cancer cells from cell culture lines from WBCs with a recovery rate better than 83%. We then demonstrated the isolation of CTCs in blood samples obtained from patients with breast cancer. Our acoustic-based separation method thus offers the potential to serve as an invaluable supplemental tool in cancer research, diagnostics, drug efficacy assessment, and therapeutics owing to its excellent biocompatibility, simple design, and label-free automated operation while offering the capability to isolate rare CTCs in a viable state. PMID:25848039

  18. Altered tumor cell growth and tumorigenicity in models of microgravity

    NASA Astrophysics Data System (ADS)

    Yamauchi, K.; Taga, M.; Furian, L.; Odle, J.; Sundaresan, A.; Pellis, N.; Andrassy, R.; Kulkarni, A.

    Spaceflight environment and microgravity (MG) causes immune dysfunction and is a major health risk to humans, especially during long-term space missions. The effects of microgravity environment on tumor growth and carcinogenesis are yet unknown. Hence, we investigated the effects of simulated MG (SMG) on tumor growth and tumorigenicity using in vivo and in vitro models. B16 melanoma cells were cultured in static flask (FL) and rotating wall vessel bioreactors (BIO) to measure growth and properties, melanin production and apoptosis. BIO cultures had 50% decreased growth (p<0.01), increased doubling time and a 150% increase in melanin production (p<0.05). Flow cytometric analysis showed increased apoptosis in BIO. When BIO cultured melanoma cells were inoculated sc in mice there was a significant increase in tumorigenicity as compared to FL cells. Thus SMG may have supported &selected highly tumorigenic cells and it is pos sible that in addition to decreased immune function MG may alter tumor cell characteristics and invasiveness. Thus it is important to study effects of microgravity environment and its stressors using experimental tumors and SMG to understand and evaluate carcinogenic responses to true microgravity. Further studies on carcinogenic events and their mechanisms will allow us develop and formulate countermeasures and protect space travelers. Additional results will be presented. (Supported by NASA NCC8-168 grant, ADK)

  19. Circulating Tumor Cells in the Adenocarcinoma of the Esophagus

    PubMed Central

    Gallerani, Giulia; Fabbri, Francesco

    2016-01-01

    Circulating tumor cells (CTCs) are elements of indisputable significance as they seem to be responsible for the onset of metastasis. Despite this, research into CTCs and their clinical application have been hindered by their rarity and heterogeneity at the molecular and cellular level, and also by a lack of technical standardization. Esophageal adenocarcinoma (EAC) is a highly aggressive cancer that is often diagnosed at an advanced stage. Its incidence has increased so much in recent years that new diagnostic, prognostic and predictive biomarkers are urgently needed. Preliminary findings suggest that CTCs could represent an effective, non-invasive, real-time assessable biomarker in all stages of EAC. This review provides an overview of EAC and CTC characteristics and reports the main research results obtained on CTCs in this setting. The need to carry out further basic and translational research in this area to confirm the clinical usefulness of CTCs and to provide oncologists with a tool to improve therapeutic strategies for EAC patients was herein highlighted. PMID:27527155

  20. Circulating tumor cell enrichment based on physical properties

    PubMed Central

    Harouaka, Ramdane A.; Nisic, Merisa; Zheng, Si-Yang

    2013-01-01

    The metastatic dissemination and spread of malignant circulating tumor cells (CTCs) accounts for over 90% of cancer related deaths. CTCs detach from a primary tumor, travel through the circulatory system, then invade and proliferate in distant organs. The detection of CTCs from blood has been established for prognostic monitoring and is predictive of patient outcome. Analysis of CTCs could enable the means for early detection and screening in cancer, as well as provide diagnostic access to tumor tissues in a minimally invasive way. The fundamental challenge with analyzing CTCs is the fact that they occur at extremely low concentrations in blood, on the order of one out of a billion cells. Various technologies have been proposed to isolate CTCs for enrichment. Here we focus on antigen-independent approaches that are not limited by specific capture antibodies. Intrinsic physical properties of CTCs including cell size, deformability, and electrical properties are reviewed, and technologies developed to exploit them for enrichment from blood are summarized. Physical enrichment technologies are of particular interest as they have the potential to increase yield, and enable the analysis of rare CTC phenotypes that may not be otherwise obtained. PMID:23832928

  1. Polyploidy and its effect on evolutionary success: old questions revisited with new tools

    PubMed Central

    Madlung, A

    2013-01-01

    Polyploidy, the condition of possessing more than two complete genomes in a cell, has intrigued biologists for almost a century. Polyploidy is found in many plants and some animal species and today we know that polyploidy has had a role in the evolution of all angiosperms. Despite its widespread occurrence, the direct effect of polyploidy on evolutionary success of a species is still largely unknown. Over the years many attractive hypotheses have been proposed in an attempt to assign functionality to the increased content of a duplicated genome. Among these hypotheses are the proposal that genome doubling confers distinct advantages to a polyploid and that these advantages allow polyploids to thrive in environments that pose challenges to the polyploid's diploid progenitors. This article revisits these long-standing questions and explores how the integration of recent genomic developments with ecological, physiological and evolutionary perspectives has contributed to addressing unresolved problems about the role of polyploidy. Although unsatisfactory, the current conclusion has to be that despite significant progress, there still isn't enough information to unequivocally answer many unresolved questions about cause and effect of polyploidy on evolutionary success of a species. There is, however, reason to believe that the increasingly integrative approaches discussed here should allow us in the future to make more direct connections between the effects of polyploidy on the genome and the responses this condition elicits from the organism living in its natural environment. PMID:23149459

  2. Tracking and Functional Characterization of Epithelial-Mesenchymal Transition and Mesenchymal Tumor Cells during Prostate Cancer Metastasis.

    PubMed

    Ruscetti, Marcus; Quach, Bill; Dadashian, Eman L; Mulholland, David J; Wu, Hong

    2015-07-01

    The epithelial-mesenchymal transition (EMT) has been postulated as a mechanism by which cancer cells acquire the invasive and stem-like traits necessary for distant metastasis. However, direct in vivo evidence for the role of EMT in the formation of cancer stem-like cells (CSC) and the metastatic cascade remains lacking. Here we report the first isolation and characterization of mesenchymal-like and EMT tumor cells, which harbor both epithelial and mesenchymal characteristics, in an autochthonous murine model of prostate cancer. By crossing the established Pb-Cre(+/-);Pten(L/L);Kras(G12D) (/+) prostate cancer model with a vimentin-GFP reporter strain, generating CPKV mice, we were able to isolate epithelial, EMT, and mesenchymal-like cancer cells based on expression of vimentin and EpCAM. CPKV mice (but not mice with Pten deletion alone) exhibited expansion of cells with EMT (EpCAM(+)/Vim-GFP(+)) and mesenchymal-like (EpCAM(-)/Vim-GFP(+)) characteristics at the primary tumor site and in circulation. These EMT and mesenchymal-like tumor cells displayed enhanced stemness and invasive character compared with epithelial tumor cells. Moreover, they displayed an enriched tumor-initiating capacity and could regenerate epithelial glandular structures in vivo, indicative of epithelia-mesenchyme plasticity. Interestingly, while mesenchymal-like tumor cells could persist in circulation and survive in the lung following intravenous injection, only epithelial and EMT tumor cells could form macrometastases. Our work extends the evidence that mesenchymal and epithelial states in cancer cells contribute differentially to their capacities for tumor initiation and metastatic seeding, respectively, and that EMT tumor cells exist with plasticity that can contribute to multiple stages of the metastatic cascade. PMID:25948589

  3. Signaling between tumor cells and the host bone marrow microenvironment.

    PubMed

    Kovacic, Natasa; Croucher, Peter I; McDonald, Michelle M

    2014-01-01

    Tumor cells with high skeletal homing affinity express numerous cell surface receptors that bind ligands produced in bone. Upon arrival, these cells survive in the host environment, encompassed in close proximity to bone marrow cells. Interactions between tumor cells and cells of the host microenvironment are essential to not only tumor cell survival but also their activation and proliferation into environment-modifying tumors. Through the production of RANKL, PTHrP, cytokines, and integrins, activated tumor cells stimulate osteoclastogenesis, enhance bone resorption, and subsequently release matrix-bound proteins that further promote tumor growth and bone resorption. In addition, alterations in the TGF-β/BMP and Wnt signaling pathways via tumor cell growth can either stimulate or suppress osteoblastic bone formation and function, leading to sclerotic or lytic bone disease, respectively. Hence, the presence of tumor cells in bone dysregulates bone remodeling, dramatically impairing skeletal integrity. Furthermore, through complex mechanisms, cells of the immune system interact with tumor cells to further impact bone remodeling. Lastly, with alterations in bone cell activity, the environment is permissive to promoting tumor growth further, suggesting an interdependence between tumor cells and bone cells in metastatic bone disease and multiple myeloma.

  4. Experimental Adaptation of Rotaviruses to Tumor Cell Lines

    PubMed Central

    Guerrero, Carlos A.; Guerrero, Rafael A.; Silva, Elver; Acosta, Orlando; Barreto, Emiliano

    2016-01-01

    A number of viruses show a naturally extended tropism for tumor cells whereas other viruses have been genetically modified or adapted to infect tumor cells. Oncolytic viruses have become a promising tool for treating some cancers by inducing cell lysis or immune response to tumor cells. In the present work, rotavirus strains TRF-41 (G5) (porcine), RRV (G3) (simian), UK (G6-P5) (bovine), Ym (G11-P9) (porcine), ECwt (murine), Wa (G1-P8), Wi61 (G9) and M69 (G8) (human), and five wild-type human rotavirus isolates were passaged multiple times in different human tumor cell lines and then combined in five different ways before additional multiple passages in tumor cell lines. Cell death caused by the tumor cell-adapted isolates was characterized using Hoechst, propidium iodide, 7-AAD, Annexin V, TUNEL, and anti-poly-(ADP ribose) polymerase (PARP) and -phospho-histone H2A.X antibodies. Multiple passages of the combined rotaviruses in tumor cell lines led to a successful infection of these cells, suggesting a gain-of-function by the acquisition of greater infectious capacity as compared with that of the parental rotaviruses. The electropherotype profiles suggest that unique tumor cell-adapted isolates were derived from reassortment of parental rotaviruses. Infection produced by such rotavirus isolates induced chromatin modifications compatible with apoptotic cell death. PMID:26828934

  5. Antitumor efficacy of vaccinia virus-modified tumor cell vaccine

    SciTech Connect

    Ito, T.; Wang, D.Q.; Maru, M.; Nakajima, K.; Kato, S.; Kurimura, T.; Wakamiya, N. )

    1990-11-01

    The antitumor efficacies of vaccinia virus-modified tumor cell vaccines were examined in murine syngeneic MH134 and X5563 tumor cells. UV-inactivated vaccinia virus was inoculated i.p. into C3H/HeN mice that had received whole body X-irradiation at 150 rads. After 3 weeks, the vaccines were administered i.p. 3 times at weekly intervals. One week after the last injection, mice were challenged i.p. with various doses of syngeneic MH134 or X5563 viable tumor cells. Four methods were used for preparing tumor cell vaccines: X-ray irradiation; fixation with paraformaldehyde for 1 h or 3 months; and purification of the membrane fraction. All four vaccines were effective, but the former two vaccines were the most effective. A mixture of the membrane fraction of untreated tumor cells and UV-inactivated vaccinia virus also had an antitumor effect. These results indicate that vaccine with the complete cell structure is the most effective. The membrane fraction of UV-inactivated vaccinia virus-absorbed tumor cells was also effective. UV-inactivated vaccinia virus can react with not only intact tumor cells but also the purified membrane fraction of tumor cells and augment antitumor activity.

  6. Cell surface syndecan-1 contributes to binding and function of macrophage migration inhibitory factor (MIF) on epithelial tumor cells.

    PubMed

    Pasqualon, Tobias; Lue, Hongqi; Groening, Sabine; Pruessmeyer, Jessica; Jahr, Holger; Denecke, Bernd; Bernhagen, Jürgen; Ludwig, Andreas

    2016-04-01

    Surface expressed proteoglycans mediate the binding of cytokines and chemokines to the cell surface and promote migration of various tumor cell types including epithelial tumor cells. We here demonstrate that binding of the chemokine-like inflammatory cytokine macrophage migration inhibitory factor (MIF) to epithelial lung and breast tumor cell lines A549 and MDA-MB231 is sensitive to enzymatic digestion of heparan sulphate chains and competitive inhibition with heparin. Moreover, MIF interaction with heparin was confirmed by chromatography and a structural comparison indicated a possible heparin binding site. These results suggested that proteoglycans carrying heparan sulphate chains are involved in MIF binding. Using shRNA-mediated gene silencing, we identified syndecan-1 as the predominant proteoglycan required for the interaction with MIF. MIF binding was decreased by induction of proteolytic shedding of syndecan-1, which could be prevented by inhibition of the metalloproteinases involved in this process. Finally, MIF induced the chemotactic migration of A549 cells, wound closure and invasion into matrigel without affecting cell proliferation. These MIF-induced responses were abrogated by heparin or by silencing of syndecan-1. Thus, our study indicates that syndecan-1 on epithelial tumor cells promotes MIF binding and MIF-mediated cell migration. This may represent a relevant mechanism through which MIF enhances tumor cell motility and metastasis.

  7. Polyploidy and small RNA regulation of cotton fiber development.

    PubMed

    Guan, Xueying; Song, Qingxin; Chen, Z Jeffrey

    2014-08-01

    Cotton is not only the most important source of renewal textile fibers, but also an excellent model for studying cell fate determination and polyploidy effects on gene expression and evolution of domestication traits. The combination of A and D-progenitor genomes into allotetraploid cotton induces intergenomic interactions and epigenetic effects, leading to the unequal expression of homoeologous genes. Small RNAs regulate the expression of transcription and signaling factors related to cellular growth, development and adaptation. An example is miRNA-mediated preferential degradation of homoeologous mRNAs encoding MYB-domain transcription factors that are required for the initiation of leaf trichomes in Arabidopsis and of seed fibers in cotton. This example of coevolution between small RNAs and their homoeologous targets could shape morphological traits such as fibers during the selection and domestication of polyploid crops.

  8. Activated tumor cell integrin αvβ3 cooperates with platelets to promote extravasation and metastasis from the blood stream

    PubMed Central

    Weber, Martin R.; Zuka, Masahiko; Lorger, Mihaela; Tschan, Mario; Torbett, Bruce E.; Zijlstra, Andries; Quigley, James P.; Staflin, Karin; Eliceiri, Brian P.; Krueger, Joseph S.; Marchese, Patricia; Ruggeri, Zaverio M.; Felding, Brunhilde H.

    2016-01-01

    Metastasis is the main cause of death in cancer patients, and understanding mechanisms that control tumor cell dissemination may lead to improved therapy. Tumor cell adhesion receptors contribute to cancer spreading. We noted earlier that tumor cells can expressing the adhesion receptor integrin αvβ3 in distinct states of activation, and found that cells which metastasize from the blood stream express it in a constitutively high affinity form. Here, we analyzed steps of the metastatic cascade in vivo and asked, when and how the affinity state of integrin αvβ3 confers a critical advantage to cancer spreading. Following tumor cells by real time PCR, non-invasive bioluminescence imaging, intravital microscopy and histology allowed us to identify tumor cell extravasation from the blood stream as a rate-limiting step supported by high affinity αvβ3. Successful transendothelial migration depended on cooperation between tumor cells and platelets involving the high affinity tumor cell integrin and release of platelet granules. Thus, this study identifies the high affinity conformer of integrin αvβ3 and its interaction with platelets as critical for early steps during hematogenous metastasis and target for prevention of metastatic disease. PMID:27067975

  9. Host adaptation and speciation through hybridization and polyploidy in Phytophthora.

    PubMed

    Bertier, Lien; Leus, Leen; D'hondt, Liesbet; de Cock, Arthur W A M; Höfte, Monica

    2013-01-01

    It is becoming increasingly evident that interspecific hybridization is a common event in phytophthora evolution. Yet, the fundamental processes underlying interspecific hybridization and the consequences for its ecological fitness and distribution are not well understood. We studied hybridization events in phytophthora clade 8b. This is a cold-tolerant group of plant pathogenic oomycetes in which six host-specific species have been described that mostly attack winter-grown vegetables. Hybrid characterization was done by sequencing and cloning of two nuclear (ITS and Ypt1) and two mitochondrial loci (Cox1 and Nadh1) combined with DNA content estimation using flow cytometry. Three different mtDNA haplotypes were recovered among the presumed hybrid isolates, dividing the hybrids into three types, with different parental species involved. In the nuclear genes, additivity, i.e. the presence of two alleles coming from different parents, was detected. Hybrid isolates showed large variations in DNA content, which was positively correlated with the additivity in nuclear loci, indicating allopolyploid hybridization followed by a process of diploidization. Moreover, indications of homeologous recombination were found in the hybrids by cloning ITS products. The hybrid isolates have been isolated from a range of hosts that have not been reported previously for clade 8b species, indicating that they have novel pathogenic potential. Next to this, DNA content measurements of the non-hybrid clade 8b species suggest that polyploidy is a common feature of this clade. We hypothesize that interspecific hybridization and polyploidy are two linked phenomena in phytophthora, and that these processes might play an important and ongoing role in the evolution of this genus.

  10. Host Adaptation and Speciation through Hybridization and Polyploidy in Phytophthora

    PubMed Central

    Bertier, Lien; Leus, Leen; D’hondt, Liesbet; de Cock, Arthur W. A. M.; Höfte, Monica

    2013-01-01

    It is becoming increasingly evident that interspecific hybridization is a common event in phytophthora evolution. Yet, the fundamental processes underlying interspecific hybridization and the consequences for its ecological fitness and distribution are not well understood. We studied hybridization events in phytophthora clade 8b. This is a cold-tolerant group of plant pathogenic oomycetes in which six host-specific species have been described that mostly attack winter-grown vegetables. Hybrid characterization was done by sequencing and cloning of two nuclear (ITS and Ypt1) and two mitochondrial loci (Cox1 and Nadh1) combined with DNA content estimation using flow cytometry. Three different mtDNA haplotypes were recovered among the presumed hybrid isolates, dividing the hybrids into three types, with different parental species involved. In the nuclear genes, additivity, i.e. the presence of two alleles coming from different parents, was detected. Hybrid isolates showed large variations in DNA content, which was positively correlated with the additivity in nuclear loci, indicating allopolyploid hybridization followed by a process of diploidization. Moreover, indications of homeologous recombination were found in the hybrids by cloning ITS products. The hybrid isolates have been isolated from a range of hosts that have not been reported previously for clade 8b species, indicating that they have novel pathogenic potential. Next to this, DNA content measurements of the non-hybrid clade 8b species suggest that polyploidy is a common feature of this clade. We hypothesize that interspecific hybridization and polyploidy are two linked phenomena in phytophthora, and that these processes might play an important and ongoing role in the evolution of this genus. PMID:24386473

  11. Circulating tumor cells in lung cancer.

    PubMed

    Young, Rachel; Pailler, Emma; Billiot, Fanny; Drusch, Françoise; Barthelemy, Amélie; Oulhen, Marianne; Besse, Benjamin; Soria, Jean-Charles; Farace, Françoise; Vielh, Philippe

    2012-01-01

    Circulating tumor cells (CTCs) have emerged as potential biomarkers in several cancers such as colon, prostate, and breast carcinomas, with a correlation between CTC number and patient prognosis being established by independent research groups. The detection and enumeration of CTCs, however, is still a developing field, with no universal method of detection suitable for all types of cancer. CTC detection in lung cancer in particular has proven difficult to perform, as CTCs in this type of cancer often present with nonepithelial characteristics. Moreover, as many detection methods rely on the use of epithelial markers to identify CTCs, the loss of these markers during epithelial-to-mesenchymal transition in certain metastatic cancers can render these methods ineffective. The development of personalized medicine has led to an increase in the advancement of molecular characterization of CTCs. The application of techniques such as FISH and RT-PCR to detect EGFR, HER2, and KRAS abnormalities in lung, breast, and colon cancer, for example, could be used to characterize CTCs in real time. The use of CTCs as a 'liquid biopsy' is therefore an exciting possibility providing information on patient prognosis and treatment efficacy. This review summarizes the state of CTC detection today, with particular emphasis on lung cancer, and discusses the future applications of CTCs in helping the clinician to develop new strategies in patient treatment. PMID:23207444

  12. Isolation of Circulating Tumor Cells by Dielectrophoresis

    PubMed Central

    Gascoyne, Peter R. C.; Shim, Sangjo

    2014-01-01

    Dielectrophoresis (DEP) is an electrokinetic method that allows intrinsic dielectric properties of suspended cells to be exploited for discrimination and separation. It has emerged as a promising method for isolating circulation tumor cells (CTCs) from blood. DEP-isolation of CTCs is independent of cell surface markers. Furthermore, isolated CTCs are viable and can be maintained in culture, suggesting that DEP methods should be more generally applicable than antibody-based approaches. The aim of this article is to review and synthesize for both oncologists and biomedical engineers interested in CTC isolation the pertinent characteristics of DEP and CTCs. The aim is to promote an understanding of the factors involved in realizing DEP-based instruments having both sufficient discrimination and throughput to allow routine analysis of CTCs in clinical practice. The article brings together: (a) the principles of DEP; (b) the biological basis for the dielectric differences between CTCs and blood cells; (c) why such differences are expected to be present for all types of tumors; and (d) instrumentation requirements to process 10 mL blood specimens in less than 1 h to enable routine clinical analysis. The force equilibrium method of dielectrophoretic field-flow fractionation (DEP-FFF) is shown to offer higher discrimination and throughput than earlier DEP trapping methods and to be applicable to clinical studies. PMID:24662940

  13. Selective gene-expression profiling of migratory tumor cells in vivo predicts clinical outcome in breast cancer patients

    PubMed Central

    2012-01-01

    Introduction Metastasis of breast cancer is the main cause of death in patients. Previous genome-wide studies have identified gene-expression patterns correlated with cancer patient outcome. However, these were derived mostly from whole tissue without respect to cell heterogeneity. In reality, only a small subpopulation of invasive cells inside the primary tumor is responsible for escaping and initiating dissemination and metastasis. When whole tissue is used for molecular profiling, the expression pattern of these cells is masked by the majority of the noninvasive tumor cells. Therefore, little information is available about the crucial early steps of the metastatic cascade: migration, invasion, and entry of tumor cells into the systemic circulation. Methods In the past, we developed an in vivo invasion assay that can capture specifically the highly motile tumor cells in the act of migrating inside living tumors. Here, we used this assay in orthotopic xenografts of human MDA-MB-231 breast cancer cells to isolate selectively the migratory cell subpopulation of the primary tumor for gene-expression profiling. In this way, we derived a gene signature specific to breast cancer migration and invasion, which we call the Human Invasion Signature (HIS). Results Unsupervised analysis of the HIS shows that the most significant upregulated gene networks in the migratory breast tumor cells include genes regulating embryonic and tissue development, cellular movement, and DNA replication and repair. We confirmed that genes involved in these functions are upregulated in the migratory tumor cells with independent biological repeats. We also demonstrate that specific genes are functionally required for in vivo invasion and hematogenous dissemination in MDA-MB-231, as well as in patient-derived breast tumors. Finally, we used statistical analysis to show that the signature can significantly predict risk of breast cancer metastasis in large patient cohorts, independent of well

  14. Effects of limonoid cedrelone on MDA-MB-231 breast tumor cells in vitro.

    PubMed

    Fuzer, Angelina M; Filho, Júlio César C; Becceneri, Amanda B; Dos Santos, Damiana A; da Silva, Maria Fátima das G F; Vieira, Paulo C; Fernandes, João B; Selistre-de-Araujo, Heloisa S; Cazal, Cristiane M; Cominetti, Márcia R

    2013-12-01

    Cancer is the second leading cause of death, preceded only by cardiovascular diseases, and there is epidemiological evidence that demonstrate this tendency is emerging worldwide. Brazil has an extensive vegetal biodiversity with more than 55,000 species listed. Such biodiversity collaborates with the finding of compounds which could be the basis for the design of new anti-tumor drugs, with fewer side effects than the conventional chemotherapy used currently. Cedrelone is a limonoid isolated from Trichilia catigua (Meliaceae) which is a native Brazilian plant. This study demonstrates that cedrelone inhibits proliferation, adhesion, migration and invasion of breast tumor cells from the line MDA-MB-231. The effects of cell migration and invasion on MDA-MB-231 cell may be explained, at least in part, by the ability of cedrelone to inhibit MMP activity. We also demonstrate that cedrelone is able to induce apoptosis in MDA-MB-231 cells. There are only a few works investigating the effect of limonoids in cellular processes closely related to tumor progression such as adhesion, migration and invasion. To the best of our knowledge, this is the first work describing the effects of a limonoid on tumor and non-tumor cell adhesion process. PMID:23869780

  15. Integrins and bone metastasis: integrating tumor cell and stromal cell interactions.

    PubMed

    Schneider, Jochen G; Amend, Sarah R; Weilbaecher, Katherine N

    2011-01-01

    Integrins on both tumor cells and the supporting host stromal cells in bone (osteoclasts, new blood vessels, inflammatory cells, platelets and bone marrow stromal cells) play key roles in enhancing bone metastasis. Tumor cells localize to specific tissues through integrin-mediated contacts with extracellular matrix and stromal cells. Integrin expression and signaling are perturbed in cancer cells, allowing them to "escape" from cell-cell and cell-matrix tethers, invade, migrate and colonize within new tissues and matrices. Integrin signaling through αvβ3 and VLA-4 on tumor cells can promote tumor metastasis to and proliferation in the bone microenvironment. Osteoclast (OC) mediated bone resorption is a critical component of bone metastasis and can promote tumor growth in bone and αvβ3 integrins are critical to OC function and development. Tumors in the bone microenvironment can recruit new blood vessel formation, platelets, pro-tumor immune cells and bone marrow stromal cells that promote tumor growth and invasion in bone. Integrins and their ligands play critical roles in platelet aggregation (αvβ3 and αIIbβ3), hematopoietic cell mobilization (VLA-4 and osteopontin), neoangiogenesis (αvβ3, αvβ5, α6β4, and β1 integrin) and stromal function (osteopontin and VLA-4). Integrins are involved in the pathogenesis of bone metastasis at many levels and further study to define integrin dysregulation by cancer will yield new therapeutic targets for the prevention and treatment of bone metastasis.

  16. Ectonucleotidases in Tumor Cells and Tumor-Associated Immune Cells: An Overview

    PubMed Central

    Bergamin, Letícia Scussel; Braganhol, Elizandra; Zanin, Rafael Fernandes; Edelweiss, Maria Isabel Albano; Battastini, Ana Maria Oliveira

    2012-01-01

    Increasing evidence points out that genetic alteration does not guarantee the development of a tumor and indicates that complex interactions of tumor cells with the microenvironment are fundamental to tumorigenesis. Among the pathological alterations that give tumor cells invasive potential, disruption of inflammatory response and the purinergic signaling are emerging as an important component of cancer progression. Nucleotide/nucleoside receptor-mediated cell communication is orchestrated by ectonucleotidases, which efficiently hydrolyze ATP, ADP, and AMP to adenosine. ATP can act as danger signaling whereas adenosine, acts as a negative feedback mechanism to limit inflammation. Many tumors exhibit alterations in ATP-metabolizing enzymes, which may contribute to the pathological events observed in solid cancer. In this paper, the main changes occurring in the expression and activity of ectonucleotidases in tumor cells as well as in tumor-associated immune cells are discussed. Furthermore, we focus on the understanding of the purinergic signaling primarily as exemplified by research done by the group on gliomas. PMID:23118517

  17. Comparative evidence for the correlated evolution of polyploidy and self-compatibility in Solanaceae.

    PubMed

    Robertson, Kelly; Goldberg, Emma E; Igić, Boris

    2011-01-01

    Breakdown of self-incompatibility occurs repeatedly in flowering plants with important evolutionary consequences. In plant families in which self-incompatibility is mediated by S-RNases, previous evidence suggests that polyploidy may often directly cause self-compatibility through the formation of diploid pollen grains. We use three approaches to examine relationships between self-incompatibility and ploidy. First, we test whether evolution of self-compatibility and polyploidy is correlated in the nightshade family (Solanaceae), and find the expected close association between polyploidy and self-compatibility. Second, we compare the rate of breakdown of self-incompatibility in the absence of polyploidy against the rate of breakdown that arises as a byproduct of polyploidization, and we find the former to be greater. Third, we apply a novel extension to these methods to show that the relative magnitudes of the macroevolutionary pathways leading to self-compatible polyploids are time dependent. Over small time intervals, the direct pathway from self-incompatible diploids is dominant, whereas the pathway through self-compatible diploids prevails over longer time scales. This pathway analysis is broadly applicable to models of character evolution in which sequential combinations of rates are compared. Finally, given the strong evidence for both irreversibility of the loss of self-incompatibility in the family and the significant association between self-compatibility and polyploidy, we argue that ancient polyploidy is highly unlikely to have occurred within the Solanaceae, contrary to previous claims based on genomic analyses.

  18. Circulating tumor cells in pancreatic cancer patients: Enrichment and cultivation

    PubMed Central

    Bobek, Vladimir; Gurlich, Robert; Eliasova, Petra; Kolostova, Katarina

    2014-01-01

    AIM: To investigate the feasibility of separation and cultivation of circulating tumor cells (CTCs) in pancreatic cancer (PaC) using a filtration device. METHODS: In total, 24 PaC patients who were candidates for surgical treatment were enrolled into the study. Peripheral blood samples were collected before an indicated surgery. For each patient, approximately 8 mL of venous blood was drawn from the antecubital veins. A new size-based separation MetaCell® technology was used for enrichment and cultivation of CTCs in vitro. (Separated CTCs were cultured on a membrane in FBS enriched RPMI media and observed by inverted microscope. The cultured cells were analyzed by means of histochemistry and immunohistochemistry using the specific antibodies to identify the cell origin. RESULTS: CTCs were detected in 16 patients (66.7%) of the 24 evaluable patients. The CTC positivity did not reflect the disease stage, tumor size, or lymph node involvement. The same percentage of CTC positivity was observed in the metastatic and non-metastatic patients (66.7% vs 66.7%). We report a successful isolation of CTCs in PaC patients capturing proliferating cells. The cells were captured by a capillary action driven size-based filtration approach that enabled cells cultures from the viable CTCs to be unaffected by any antibodies or lysing solutions. The captured cancer cells displayed plasticity which enabled some cells to invade the separating membrane. Further, the cancer cells in the “bottom fraction”, may represent a more invasive CTC-fraction. The CTCs were cultured in vitro for further downstream applications. CONCLUSION: The presented size-based filtration method enables culture of CTCs in vitro for possible downstream applications. PMID:25493031

  19. Circulating Tumor Cell Composition in Renal Cell Carcinoma

    PubMed Central

    Bublitz, Kira; Lazaridis, Lazaros; Goergens, André; Giebel, Bernd; Schuler, Martin; Hoffmann, Andreas-Claudius

    2016-01-01

    Purpose Due to their minimal-invasive yet potentially current character circulating tumor cells (CTC) might be useful as a “liquid biopsy” in solid tumors. However, successful application in metastatic renal cell carcinoma (mRCC) has been very limited so far. High plasticity and heterogeneity of CTC morphology challenges currently available enrichment and detection techniques with EpCAM as the usual surface marker being underrepresented in mRCC. We recently described a method that enables us to identify and characterize non-hematopoietic cells in the peripheral blood stream with varying characteristics and define CTC subgroups that distinctly associate to clinical parameters. With this pilot study we wanted to scrutinize feasibility of this approach and its potential usage in clinical studies. Experimental Design Peripheral blood was drawn from 14 consecutive mRCC patients at the West German Cancer Center and CTC profiles were analyzed by Multi-Parameter Immunofluorescence Microscopy (MPIM). Additionally angiogenesis-related genes were measured by quantitative RT-PCR analysis. Results We detected CTC with epithelial, mesenchymal, stem cell-like or mixed-cell characteristics at different time-points during anti-angiogenic therapy. The presence and quantity of N-cadherin-positive or CD133-positive CTC was associated with inferior PFS. There was an inverse correlation between high expression of HIF1A, VEGFA, VEGFR and FGFR and the presence of N-cadherin-positive and CD133-positive CTC. Conclusions Patients with mRCC exhibit distinct CTC profiles that may implicate differences in therapeutic outcome. Prospective evaluation of phenotypic and genetic CTC profiling as prognostic and predictive biomarker in mRCC is warranted. PMID:27101285

  20. Tanaka Circulating Tumor Cells (CTCs) — EDRN Public Portal

    Cancer.gov

    Circulating tumor cells (CTC) can be found and quantitatively evaluated with a semiautomated system (CellSearch) in patients with primary lung cancer. CTC count is a useful diagnostic marker to predict development of distant metastasis.

  1. Distinctive responses of brain tumor cells to TLR2 ligands.

    PubMed

    Yoon, Hee Jung; Jeon, Sae-Bom; Koh, Han Seok; Song, Jae-Young; Kim, Sang Soo; Kim, In-Hoo; Park, Eun Jung

    2015-05-01

    Malignant brain tumor mass contains significant numbers of infiltrating glial cells that may intimately interact with tumor cells and influence cancer treatments. Understanding of characteristic discrepancies between normal GLIA and tumor cells would, therefore, be valuable for improving anticancer therapeutics. Here, we report distinct differences in toll-like receptors (TLR)-2-mediated responses between normal glia and primary brain tumor cell lines. We found that tyrosine phosphorylation of STAT1 by TLR2 ligands and its downstream events did not occur in mouse, rat, or human brain tumor cell lines, but were markedly induced in normal primary microglia and astrocytes. Using TLR2-deficient, interferon (IFN)-γ-deficient, and IFNγ-receptor-1-deficient mice, we revealed that the impaired phosphorylation of STAT1 might be linked with defective TLR2 system in tumor cells, and that a TLR2-dependent pathway, not IFNγ-receptor machinery, might be critical for tyrosine STAT1 phosphorylation by TLR2 ligands. We also found that TLR2 and its heterodimeric partners, TLR1 and 6, on brain tumor cells failed to properly respond to TLR2 ligands, and representative TLR2-dependent cellular events, such as inflammatory responses and cell death, were not detected in brain tumor cells. Similar results were obtained in in vitro and in vivo experiments using orthotopic mouse and rat brain tumor models. Collectively, these results suggest that primary brain tumor cells may exhibit a distinctive dysfunction of TLR2-associated responses, resulting in abnormal signaling and cellular events. Careful targeting of this distinctive property could serve as the basis for effective therapeutic approaches against primary brain tumors.

  2. Stromal Activation by Tumor Cells: An in Vitro Study in Breast Cancer

    PubMed Central

    Merlino, Giuseppe; Miodini, Patrizia; Paolini, Biagio; Carcangiu, Maria Luisa; Gennaro, Massimiliano; Dugo, Matteo; Daidone, Maria Grazia; Cappelletti, Vera

    2016-01-01

    Background: The tumor microenvironment participates in the regulation of tumor progression and influences treatment sensitivity. In breast cancer, it also may play a role in determining the fate of non-invasive lesions such as ductal carcinoma in situ (DCIS), a non-obligate precursor of invasive diseases, which is aggressively treated despite its indolent nature in many patients since no biomarkers are available to predict the progression of DCIS to invasive disease. In vitro models of stromal activation by breast tumor cells might provide clues as to specific stromal genes crucial for the transition from DCIS to invasive disease. Methods: normal human dermal fibroblasts (NHDF) were treated under serum-free conditions with cell culture media conditioned by breast cancer cell lines (SkBr3, MDA-MB-468, T47D) for 72 h and subjected to gene expression profiling with Illumina platform. Results: TGM2, coding for a tissue transglutaminase, was identified as candidate gene for stromal activation. In public transcriptomic datasets of invasive breast tumors TGM2 expression proved to provide prognostic information. Conversely, its role as an early biosensor of tumor invasiveness needs to be further investigated by in situ analyses. Conclusion: Stromal TGM2 might probably be associated with precancerous evolution at earlier stages compared to DCIS. PMID:27600076

  3. Stromal Activation by Tumor Cells: An in Vitro Study in Breast Cancer

    PubMed Central

    Merlino, Giuseppe; Miodini, Patrizia; Paolini, Biagio; Carcangiu, Maria Luisa; Gennaro, Massimiliano; Dugo, Matteo; Daidone, Maria Grazia; Cappelletti, Vera

    2016-01-01

    Background: The tumor microenvironment participates in the regulation of tumor progression and influences treatment sensitivity. In breast cancer, it also may play a role in determining the fate of non-invasive lesions such as ductal carcinoma in situ (DCIS), a non-obligate precursor of invasive diseases, which is aggressively treated despite its indolent nature in many patients since no biomarkers are available to predict the progression of DCIS to invasive disease. In vitro models of stromal activation by breast tumor cells might provide clues as to specific stromal genes crucial for the transition from DCIS to invasive disease. Methods: normal human dermal fibroblasts (NHDF) were treated under serum-free conditions with cell culture media conditioned by breast cancer cell lines (SkBr3, MDA-MB-468, T47D) for 72 h and subjected to gene expression profiling with Illumina platform. Results: TGM2, coding for a tissue transglutaminase, was identified as candidate gene for stromal activation. In public transcriptomic datasets of invasive breast tumors TGM2 expression proved to provide prognostic information. Conversely, its role as an early biosensor of tumor invasiveness needs to be further investigated by in situ analyses. Conclusion: Stromal TGM2 might probably be associated with precancerous evolution at earlier stages compared to DCIS.

  4. Increased efficiency of immunotherapy using irradiated tumor cells.

    PubMed

    Wu, J M; Fitzgerald, J; Sonis, S; Ravikumar, T; Wilson, R

    1987-01-01

    The efficacy of irradiated tumor cells combined with chemotherapy or non-specific immunostimulation with complete Freund's adjuvant was tested in a model of minimal residual tumor-bearing syngeneic mice. Male C57BL/6J mice were innoculated in the right rear leg with live tumor cells from a methylcholanthrene induced fibrosarcoma. The tumor was resected when it reached 0.7 cm in diameter and animals were treated with doses of irradiated tumor cells (XTC) from the primary tumor ranging in number from 1 X 10(3) to 9 X 10(3). Best survival was noted using 5 X 10(3) XTC combined with irradiated tumor cells of liver or pulmonary metastases origin, complete Freund's adjuvant or cytoxan. The combination of irradiated tumor cells of metastatic origin did not enhance the therapeutic effect of XTC alone. Freund's adjuvant was not of benefit in enhancing the efficacy of XTC. However, improved survival was noted when chemotherapy in the form of cytoxan was used to supplement XTC. Our data suggests that XTC is more efficacious as a mode of immunotherapy than are live tumor cells. The dose of XTC used is critical in determining its effect. Chemotherapy appears to enhance the benefit of XTC.

  5. Wound-Induced Polyploidy Is Required for Tissue Repair

    PubMed Central

    Losick, Vicki P.

    2016-01-01

    Significance: All organs suffer wounds to some extent during an animal's lifetime and to compensate for cell loss, tissues often rely on cell division. However, many organs are made up of differentiated cells with only a limited capacity to divide. It is not well understood how cells are replaced in the absence of cell division. Recent Advances: Recent studies in the model organism Drosophila melanogaster have proven that wound-induced polyploidy (WIP) is an essential mechanism to replace tissue mass and restore tissue integrity in the absence of cell division. In this repair mechanism, preexisting differentiated cells increase their DNA content and cell size by becoming polyploid. Critical Issues: Cells within mammalian organs such as the liver, heart, and cornea have also been observed to increase their DNA ploidy in response to injury, suggesting that WIP may be an evolutionarily conserved mechanism to compensate for cell loss. Future Directions: The Hippo signal transduction pathway is required for differentiated cells to initiate WIP in Drosophila. Continued studies in Drosophila will help to identify other signaling pathways required for WIP as well as the conserved mechanisms that polyploid cells may play during wound repair in all organisms. PMID:27274437

  6. Influence of Anti-Mouse Interferon Serum on the Growth and Metastasis of Tumor Cells Persistently Infected with Virus and of Human Prostatic Tumors in Athymic Nude Mice

    NASA Astrophysics Data System (ADS)

    Reid, Lola M.; Minato, Nagahiro; Gresser, Ion; Holland, John; Kadish, Anna; Bloom, Barry R.

    1981-02-01

    Baby hamster kidney or HeLa cells form tumors in 100% of athymic nude mice. When such cells are persistently infected (PI) with RNA viruses, such as mumps or measles virus, the tumor cells either fail to grow or form circumscribed benign nodules. Neither the parental nor the virus PI tumor cells form invasive or metastatic lesions in nude mice. Previous studies have indicated a correlation between the susceptibility of virus-PI tumor cells in vitro and the cytolytic activity of natural killer (NK) cells and their failure to grow in vivo. Because interferon (IF) is the principal regulatory molecule governing the differentiation of NK cells, it was possible to test the relevance of the IF--NK cell system in vivo to restriction of tumor growth by treatment of nude mice with anti-IF globulin. This treatment was shown to reduce both IF production and NK activity in spleen cells. Both parental and virus-PI tumor cells grew and formed larger tumors in nude mice treated with anti-IF globulin than in control nude mice. The viral-PI tumor cells and the uninfected parental cells formed tumors in treated mice that were highly invasive and often metastatic. Some human tumor types have been notoriously difficult to establish as tumor lines in nude mice (e.g., primary human prostatic carcinomas). When transplanted into nude mice treated either with anti-IF globulin or anti-lymphocyte serum, two prostatic carcinomas grew and produced neoplasms with local invasiveness and some metastases. The results are consistent with the view that interferon may be important in restricting the growth, invasiveness, and metastases of tumor cells by acting indirectly through components of the immune system, such as NK cells.

  7. Imaging Circulating Tumor Cells in Freely Moving Awake Small Animals Using a Miniaturized Intravital Microscope

    PubMed Central

    Sasportas, Laura Sarah; Gambhir, Sanjiv Sam

    2014-01-01

    Metastasis, the cause for 90% of cancer mortality, is a complex and poorly understood process involving the invasion of circulating tumor cells (CTCs) into blood vessels. These cells have potential prognostic value as biomarkers for early metastatic risk. But their rarity and the lack of specificity and sensitivity in measuring them render their interrogation by current techniques very challenging. How and when these cells are circulating in the blood, on their way to potentially give rise to metastasis, is a question that remains largely unanswered. In order to provide an insight into this "black box" using non-invasive imaging, we developed a novel miniature intravital microscopy (mIVM) strategy capable of real-time long-term monitoring of CTCs in awake small animals. We established an experimental 4T1-GL mouse model of metastatic breast cancer, in which tumor cells express both fluorescent and bioluminescent reporter genes to enable both single cell and whole body tumor imaging. Using mIVM, we monitored blood vessels of different diameters in awake mice in an experimental model of metastasis. Using an in-house software algorithm we developed, we demonstrated in vivo CTC enumeration and computation of CTC trajectory and speed. These data represent the first reported use we know of for a miniature mountable intravital microscopy setup for in vivo imaging of CTCs in awake animals. PMID:24497977

  8. Efficient Purification and Release of Circulating Tumor Cells by Synergistic Effect of Biomarker and SiO2 @Gel-Microbead-Based Size Difference Amplification.

    PubMed

    Huang, Qinqin; Cai, Bo; Chen, Bolei; Rao, Lang; He, Zhaobo; He, Rongxiang; Guo, Feng; Zhao, Libo; Kondamareddy, Kiran Kumar; Liu, Wei; Guo, Shishang; Zhao, Xing-Zhong

    2016-07-01

    Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies. PMID:27028055

  9. Targeting VEGFR1- and VEGFR2-expressing non-tumor cells is essential for esophageal cancer therapy

    PubMed Central

    Xu, Wen Wen; Li, Bin; Lam, Alfred KY; Tsao, Sai Wah; Law, Simon YK; Chan, Kwok Wah; Yuan, Qiu Ju; Cheung, Annie LM

    2015-01-01

    Increasing appreciation of tumor heterogeneity and the tumor-host interaction has stimulated interest in developing novel therapies that target both tumor cells and tumor microenvironment. Bone marrow derived cells (BMDCs) constitute important components of the tumor microenvironment. In this study, we aim to investigate the significance of VEGFR1- and VEGFR2-expressing non-tumor cells, including BMDCs, in esophageal cancer (EC) progression and in VEGFR1/VEGFR2-targeted therapies. Here we report that VEGFR1 or VEGFR2 blockade can significantly attenuate VEGF-induced Src and Erk signaling, as well as the proliferation and migration of VEGFR1+ and VEGFR2+ bone marrow cells and their pro-invasive effect on cancer cells. Importantly, our in vivo data show for the first time that systemic blockade of VEGFR1+ or VEGFR2+ non-tumor cells with neutralizing antibodies is sufficient to significantly suppress esophageal tumor growth, angiogenesis and metastasis in mice. Moreover, our tissue microarray study of human EC clinical specimens showed the clinicopathological significance of VEGFR1 and VEGFR2 in EC, which suggest that anti-VEGFR1/VEGFR2 therapies may be particularly beneficial for patients with aggressive EC. In conclusion, this study demonstrates the important contributions of VEGFR1+ and VEGFR2+ non-tumor cells in esophageal cancer progression, and substantiates the validity of these receptors as therapeutic targets for this deadly disease. PMID:25595897

  10. How does cancer cell metabolism affect tumor migration and invasion?

    PubMed

    Han, Tianyu; Kang, De; Ji, Daokun; Wang, Xiaoyu; Zhan, Weihua; Fu, Minggui; Xin, Hong-Bo; Wang, Jian-Bin

    2013-01-01

    Cancer metastasis is the major cause of cancer-associated death. Accordingly, identification of the regulatory mechanisms that control whether or not tumor cells become "directed walkers" is a crucial issue of cancer research. The deregulation of cell migration during cancer progression determines the capacity of tumor cells to escape from the primary tumors and invade adjacent tissues to finally form metastases. The ability to switch from a predominantly oxidative metabolism to glycolysis and the production of lactate even when oxygen is plentiful is a key characteristic of cancer cells. This metabolic switch, known as the Warburg effect, was first described in 1920s, and affected not only tumor cell growth but also tumor cell migration. In this review, we will focus on the recent studies on how cancer cell metabolism affects tumor cell migration and invasion. Understanding the new aspects on molecular mechanisms and signaling pathways controlling tumor cell migration is critical for development of therapeutic strategies for cancer patients.

  11. Current challenges in metastasis: disseminated and circulating tumor cells detection.

    PubMed

    Shahneh, Fatemeh Zare

    2013-01-01

    Metastatic dissemination of the primary tumor is responsible for the majority of cancer-related morbidity and mortality. Detection of disseminated tumor cells in the bone marrow and circulating tumor cells in the peripheral blood is associated with early metastatic recurrence in cancer. Circulating tumor cells (CTCs) shed from the site of disease in metastatic or primary tumor that can be recognized and enriched in the peripheral blood of cancer patients. The detection of rare circulating tumor cells (CTC) is an objective of numerous oncologists' researches. Circulating tumor cells have the potential to help to detect cancer recurrence at its earlier stage, determine therapy resistance before full blown progression, distinguish molecular changes during treatment, monitor efficacy therapy during treatment, guide therapy choice, and predict clinical outcome. In future perspective, standardization of the different enrichment methods in clinical trial is integrated. Developments in CTC detection methods will improve a wide range of clinical applications, as well as the discovery of biomarkers to predict treatment responses and disease progression. In order to identifying, several techniques have been applied to detect and isolate CTC in a heterogeneous population for management and monitoring response to therapy in clinical course in patients with localized or metastatic disease.

  12. Apoptosis and tumor cell death in response to HAMLET (human alpha-lactalbumin made lethal to tumor cells).

    PubMed

    Hallgren, Oskar; Aits, Sonja; Brest, Patrick; Gustafsson, Lotta; Mossberg, Ann-Kristin; Wullt, Björn; Svanborg, Catharina

    2008-01-01

    HAMLET (human alpha-lactalbumin made lethal to tumor cells) is a molecular complex derived from human milk that kills tumor cells by a process resembling programmed cell death. The complex consists of partially unfolded alpha-lactalbumin and oleic acid, and both the protein and the fatty acid are required for cell death. HAMLET has broad antitumor activity in vitro, and its therapeutic effect has been confirmed in vivo in a human glioblastoma rat xenograft model, in patients with skin papillomas and in patients with bladder cancer. The mechanisms of tumor cell death remain unclear, however. Immediately after the encounter with tumor cells, HAMLET invades the cells and causes mitochondrial membrane depolarization, cytochrome c release, phosphatidyl serine exposure, and a low caspase response. A fraction of the cells undergoes morphological changes characteristic of apoptosis, but caspase inhibition does not rescue the cells and Bcl-2 overexpression or altered p53 status does not influence the sensitivity of tumor cells to HAMLET. HAMLET also creates a state of unfolded protein overload and activates 20S proteasomes, which contributes to cell death. In parallel, HAMLET translocates to tumor cell nuclei, where high-affinity interactions with histones cause chromatin disruption, loss of transcription, and nuclear condensation. The dying cells also show morphological changes compatible with macroautophagy, and recent studies indicate that macroautophagy is involved in the cell death response to HAMLET. The results suggest that HAMLET, like a hydra with many heads, may interact with several crucial cellular organelles, thereby activating several forms of cell death, in parallel. This complexity might underlie the rapid death response of tumor cells and the broad antitumor activity of HAMLET.

  13. Watching the grin fade: tracing the effects of polyploidy on different evolutionary time scales.

    PubMed

    Mayfield-Jones, Dustin; Washburn, Jacob D; Arias, Tatiana; Edger, Patrick P; Pires, J Chris; Conant, Gavin C

    2013-04-01

    Polyploidy, or whole-genome duplication (WGD), is a recurrent mutation both in cell lineages and over evolutionary time. By globally changing the relationship between gene copy number and other cellular entities, it can induce dramatic changes at the cellular and phenotypic level. Perhaps surprisingly, then, the insights that these events can bring to understanding other cellular features are not as well appreciated as they could be. In this review, we draw on examples of polyploidy from animals, plants and yeast to explore how investigations of polyploid cells have improved our understanding of the cell cycle, biological network complexity, metabolic phenotypes and tumor biology. We argue that the study of polyploidy across organisms, cell types, and time scales serves not only as a window into basic cell biology, but also as a basis for a predictive biology with applications ranging from crop improvement to treating cancer.

  14. [Tumor Cells and Micro-environment in Brain Metastases].

    PubMed

    Zhong, Wen; Hu, Chengping

    2016-09-20

    Improvements in survival and quality of life of patients with lung cancer had been achieved due to the progression of early diagnosis and precision medicine at recent years, however, until now, treatments targeted at lesions in central nervous system are far from satisfying, thus threatening livelihood of patients involved. After all, in the issue of prophylaxis and therapeutics of brain metastases, it is crucial to learn about the biological behavior of tumor cells in brain metastases and its mechanism underlying, and the hypothesis "seed and soil", that is, tumor cells would generate series of adaptive changes to fit in the new environment, is liable to help explain this process well. In this assay, we reviewed documents concerning tumor cells, brain micro-environments and their interactions in brain metastases, aiming to provide novel insight into the treatments of brain metastases. PMID:27666556

  15. Non-coding RNAs regulate tumor cell plasticity.

    PubMed

    Liu, Bodu; Sun, Lijuan; Song, Erwei

    2013-10-01

    Tumor metastasis is one of the most serious challenges for human cancers as the majority of deaths caused by cancer are associated with metastasis, rather than the primary tumor. Recent studies have demonstrated that tumor cell plasticity plays a critical role in tumor metastasis by giving rise to various cell types which is necessary for tumor to invade adjacent tissues and form distant metastasis. These include differentiation of cancer stem cells (CSCs), or epithelial-mesenchymal transition (EMT) and its reverse process, mesenchymal-epithelial transition (MET). A growing body of evidence has demonstrated that the biology of tumor cell plasticity is tightly linked to functions of non-coding RNAs (ncRNAs), especially microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Therefore, understanding the mechanisms how non-coding RNAs regulate tumor cell plasticity is essential for discovery of new diagnostic markers and therapeutic targets to overcome metastasis.

  16. HAMLET interacts with histones and chromatin in tumor cell nuclei.

    PubMed

    Düringer, Caroline; Hamiche, Ali; Gustafsson, Lotta; Kimura, Hiroshi; Svanborg, Catharina

    2003-10-24

    HAMLET is a folding variant of human alpha-lactalbumin in an active complex with oleic acid. HAMLET selectively enters tumor cells, accumulates in their nuclei and induces apoptosis-like cell death. This study examined the interactions of HAMLET with nuclear constituents and identified histones as targets. HAMLET was found to bind histone H3 strongly and to lesser extent histones H4 and H2B. The specificity of these interactions was confirmed using BIAcore technology and chromatin assembly assays. In vivo in tumor cells, HAMLET co-localized with histones and perturbed the chromatin structure; HAMLET was found associated with chromatin in an insoluble nuclear fraction resistant to salt extraction. In vitro, HAMLET bound strongly to histones and impaired their deposition on DNA. We conclude that HAMLET interacts with histones and chromatin in tumor cell nuclei and propose that this interaction locks the cells into the death pathway by irreversibly disrupting chromatin organization.

  17. Plasma-activated medium induced apoptosis on tumor cells

    NASA Astrophysics Data System (ADS)

    Hori, Masaru; Tanaka, Hiromasa; Mizuno, Masaaki; Nakamura, Kae; Kajiyama, Hiroaki; Takeda, Keigo; Ishikawa, Kenji; Kano, Hiroyuki; Kikkawa, Fumitaka

    2013-09-01

    The non-equilibrium atmospheric pressure plasma (NEAPP) has attracted attention in cancer therapy. In this study, the fresh medium was treated with our developed NEAPP, ultra-high electron density (approximately 2 × 1016 cm-3). The medium called the plasma-activated medium (PAM) killed not normal cells but tumor cells through induction of apoptosis. Cell proliferation assays showed that the tumor cells were selectively killed by the PAM. Those cells induced apoptosis using an apoptotic molecular marker, cleaved Caspase3/7. The molecular mechanisms of PAM-mediated apoptosis in the tumor cells were also found that the PAM downregulated the expression of AKT kinase, a marker molecule in a survival signal transduction pathway. These results suggest that PAM may be a promising tool for tumor therapy by downregulating the survival signals in cancers.

  18. Tumor cell traffic through the extracellular matrix is controlled by the membrane-anchored collagenase MT1-MMP

    PubMed Central

    Sabeh, Farideh; Ota, Ichiro; Holmbeck, Kenn; Birkedal-Hansen, Henning; Soloway, Paul; Balbin, Milagros; Lopez-Otin, Carlos; Shapiro, Steven; Inada, Masaki; Krane, Stephen; Allen, Edward; Chung, Duane; Weiss, Stephen J.

    2004-01-01

    As cancer cells traverse collagen-rich extracellular matrix (ECM) barriers and intravasate, they adopt a fibroblast-like phenotype and engage undefined proteolytic cascades that mediate invasive activity. Herein, we find that fibroblasts and cancer cells express an indistinguishable pericellular collagenolytic activity that allows them to traverse the ECM. Using fibroblasts isolated from gene-targeted mice, a matrix metalloproteinase (MMP)–dependent activity is identified that drives invasion independently of plasminogen, the gelatinase A/TIMP-2 axis, gelatinase B, collagenase-3, collagenase-2, or stromelysin-1. In contrast, deleting or suppressing expression of the membrane-tethered MMP, MT1-MMP, in fibroblasts or tumor cells results in a loss of collagenolytic and invasive activity in vitro or in vivo. Thus, MT1-MMP serves as the major cell-associated proteinase necessary to confer normal or neoplastic cells with invasive activity. PMID:15557125

  19. Newcastle disease virus selectively kills human tumor cells.

    PubMed

    Reichard, K W; Lorence, R M; Cascino, C J; Peeples, M E; Walter, R J; Fernando, M B; Reyes, H M; Greager, J A

    1992-05-01

    Newcastle disease virus (NDV), strain 73-T, has previously been shown to be cytolytic to mouse tumor cells. In this study, we have evaluated the ability of NDV to replicate in and kill human tumor cells in culture and in athymic mice. Plaque assays were used to determine the cytolytic activity of NDV on six human tumor cell lines, fibrosarcoma (HT1080), osteosarcoma (KHOS), cervical carcinoma (KB8-5-11), bladder carcinoma (HCV29T), neuroblastoma (IMR32), and Wilm's tumor (G104), and on nine different normal human fibroblast lines. NDV formed plaques on all tumor cells tested as well as on chick embryo cells (CEC), the native host for NDV. Plaques did not form on any of the normal fibroblast lines. To detect NDV replication, virus yield assays were performed which measured virus particles in infected cell culture supernatants. Virus yield increased 10,000-fold within 24 hr in tumor and CEC supernatants. Titers remained near zero in normal fibroblast supernatants. In vivo tumoricidal activity was evaluated in athymic nude Balb-c mice by subcutaneous injection of 9 x 10(6) tumor cells followed by intralesional injection of either live or heat-killed NDV (1.0 x 10(6) plaque forming units [PFU]), or medium. After live NDV treatment, tumor regression occurred in 10 out of 11 mice bearing KB8-5-11 tumors, 8 out of 8 with HT-1080 tumors, and 6 out of 7 with IMR-32 tumors. After treatment with heat-killed NDV no regression occurred (P less than 0.01, Fisher's exact test). Nontumor-bearing mice injected with 1.0 x 10(8) PFU of NDV remained healthy. These results indicate that NDV efficiently and selectively replicates in and kills tumor cells, but not normal cells, and that intralesional NDV causes complete tumor regression in athymic mice with a high therapeutic index.

  20. Ovarian Tumor Cells Studied Aboard the International Space Station (ISS)

    NASA Technical Reports Server (NTRS)

    2001-01-01

    In August 2001, principal investigator Jeanne Becker sent human ovarian tumor cells to the International Space Station (ISS) aboard the STS-105 mission. The tumor cells were cultured in microgravity for a 14 day growth period and were analyzed for changes in the rate of cell growth and synthesis of associated proteins. In addition, they were evaluated for the expression of several proteins that are the products of oncogenes, which cause the transformation of normal cells into cancer cells. This photo, which was taken by astronaut Frank Culbertson who conducted the experiment for Dr. Becker, shows two cell culture bags containing LN1 ovarian carcinoma cell cultures.

  1. Single-cell analyses of circulating tumor cells

    PubMed Central

    Chen, Xi-Xi; Bai, Fan

    2015-01-01

    Circulating tumor cells (CTCs) are a population of tumor cells mediating metastasis, which results in most of the cancer related deaths. The number of CTCs in the peripheral blood of patients is rare, and many platforms have been launched for detection and enrichment of CTCs. Enumeration of CTCs has already been used as a prognosis marker predicting the survival rate of cancer patients. Yet CTCs should be more potential. Studies on CTCs at single cell level may help revealing the underlying mechanism of tumorigenesis and metastasis. Though far from developed, this area of study holds much promise in providing new clinical application and deep understanding towards metastasis and cancer development. PMID:26487963

  2. Single-cell analyses of circulating tumor cells.

    PubMed

    Chen, Xi-Xi; Bai, Fan

    2015-09-01

    Circulating tumor cells (CTCs) are a population of tumor cells mediating metastasis, which results in most of the cancer related deaths. The number of CTCs in the peripheral blood of patients is rare, and many platforms have been launched for detection and enrichment of CTCs. Enumeration of CTCs has already been used as a prognosis marker predicting the survival rate of cancer patients. Yet CTCs should be more potential. Studies on CTCs at single cell level may help revealing the underlying mechanism of tumorigenesis and metastasis. Though far from developed, this area of study holds much promise in providing new clinical application and deep understanding towards metastasis and cancer development.

  3. X-ray sensitivity of human tumor cells in vitro

    SciTech Connect

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-04-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D/sub 0/). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability.

  4. Identification of genomic signatures in circulating tumor cells from breast cancer.

    PubMed

    Kanwar, Nisha; Hu, Pingzhao; Bedard, Philippe; Clemons, Mark; McCready, David; Done, Susan J

    2015-07-15

    Levels of circulating tumor cells (CTCs) in blood have prognostic value in early and metastatic breast cancer. CTCs also show varying degrees of concordance with molecular markers of primary tumors they originate from. It is expected that individual cells reflect the heterogeneity and evolution of tumor cells as they acquire new functions and differential responses to chemotherapy. However, a degree of commonality is also plausible, highlighting alterations that allow tumor cells to perform CTC-defining activities such as invasion and intravasation. Using a matched tumor-normal approach, we performed high-resolution copy number profiling of CTCs from breast cancer to identify occult changes occurring during progression to metastasis. We identified a signature of recurrent gain in CTCs, consisting of 90 minimal common regions (MCRs) of copy number gain. These were predominantly found across chromosome 19 and were identified at low frequencies (3-4%) in 787 primary breast carcinomas examined. CTC genomic signatures clustered into two groups independent of subtype: a dormancy-related signature with 16 MCRs (AKT2, PTEN, CADM2); and a tumor-aggressiveness related signature with 358 MCRs (ANGPTL4, BSG, MIR-373). There were two MCRs in common between the groups on 19q13 and 21q21, containing genes involved in resistance to anoikis, TGFβ-signaling and metastasis (TFF3, LTBP4, NUMBL). Furthermore, a region harboring the ERBB2 gene was gained in a majority of patients. Regions 20q13 and 15q24 were associated with distant metastasis. The distinctiveness of CTC signatures highlights cell populations with different functional or metastatic potential. Such novel targets could help to specifically identify and block dissemination.

  5. The biological and clinical importance of epithelial-mesenchymal transition in circulating tumor cells.

    PubMed

    Liu, Huiying; Zhang, Xiaofeng; Li, Jun; Sun, Bin; Qian, Haihua; Yin, Zhengfeng

    2015-02-01

    Movement of tumor cells from a primary tumor to a nonadjacent or distant site is a contiguous and complex process. Among the multiple natural cellular programs that promote initiation and progression of tumor metastasis, epithelial-mesenchymal transition (EMT) may play a key role in the ultimate generation of a metastatic foci. Acquisition of the EMT phenotype by tumor cells not only increases their migration and invasion potentials, thereby facilitating their ability to infiltrate blood vessels and to produce circulating tumor cells (CTCs), but also promotes survival of CTCs in the bloodstream and their ability to extravasate out of the circulatory system and invade proximal tissues. In organs distal to the primary tumor, the phenotypic switching mechanism of mesenchymal-epithelial transition (MET) enables CTCs to grow and colonize, enhancing the likelihood of establishing metastasis. In addition, CTCs that have undergone EMT attain increased resistance to chemotherapy and targeted therapy. CTCs with the EMT phenotype have become recognized as an active source of metastases, and targeting EMT/MET processes during the individual steps of tumor metastasis represents a promising new approach for alleviating cancer metastasis and recurrence. In this article, we focus on the biological and clinical importance of EMT and/or MET in CTCs during the individual steps of tumor metastasis, summarizing the recent findings of the regulatory roles played by EMT and/or MET in the generation, survival, and recolonization of CTCs and discussing the EMT-targeting strategies developed for tumor diagnosis as well as their potential for management of metastatic malignant diseases.

  6. The same and not the same: heterogeneous functional activation of prostate tumor cells by TLR ligation

    PubMed Central

    2014-01-01

    Background Many types of tumors are organized in a hierarchy of heterogeneous cell populations with different molecular signature. Such heterogeneity may be associated with different responsiveness to microenvironment stimuli. In the present study, the effects of lipopolysaccharide (LPS) and lipoteichoic acid (LTA), as well-known mediators of inflammation, on cancerous behavior of three prostate tumor cells, LNCaP, PC3 and DU145, were investigated. Methods Expression of TLR1-10, CD14 and MyD88 transcripts was investigated by RT-PCR. Protein expression of TLR2 and 4 was scrutinized by flow cytometry, immunofluorescent staining and Western blotting. Experiments were set up to assess the effects of LPS and LTA at different concentrations and times on cell proliferation, extracellular matrix invasion, adhesion and cytokine production. Results We showed that prostate cancer cell lines differentially express TLR1-10, MyD88 and CD14 transcripts. DU145 failed to express TLR4 gene. Positively-identified TLR2 protein in all prostate cancer cells and TLR4 protein in PC3 and LNCaP by Western blotting was not accompanied by cell surface expression, as judged by flow cytometry. Immunofluorescent staining clearly demonstrated predominantly perinuclear localization of TLR2 and TLR4. LTA activation of all prostate cancer cells significantly increased cell proliferation. Regardless of lacking TLR4, DU145 cells proliferated in response to LPS treatment. While LPS caused increased invasiveness of LNCaP, invasive capacity of PC3 was significantly reduced after LPS or LTA stimulation. Stimulation of all prostate tumor cells with LTA was associated with increased cell adhesion and IL-8 production. IL-6 production, however, was differentially regulated by LPS stimulation in prostate tumor cells. Conclusion The data shows that cancer cells originated from the same histologically origin exhibit heterogeneous response to the same TLR ligand. Therefore, a thorough and comprehensive judgment

  7. Fes tyrosine kinase expression in the tumor niche correlates with enhanced tumor growth, angiogenesis, circulating tumor cells, metastasis, and infiltrating macrophages.

    PubMed

    Zhang, Shengnan; Chitu, Violeta; Stanley, E Richard; Elliott, Bruce E; Greer, Peter A

    2011-02-15

    Fes is a protein tyrosine kinase with cell autonomous oncogenic activities that are well established in cell culture and animal models, but its involvement in human cancer has been unclear. Abundant expression of Fes in vascular endothelial cells and myeloid cell lineages prompted us to explore roles for Fes in the tumor microenvironment. In an orthotopic mouse model of breast cancer, we found that loss of Fes in the host correlated with reductions in engrafted tumor growth rates, metastasis, and circulating tumor cells. The tumor microenvironment in Fes-deficient mice also showed reduced vascularity and fewer macrophages. In co-culture with tumor cells, Fes-deficient macrophages also poorly promoted tumor cell invasive behavior. Taken together, our observations argue that Fes inhibition might provide therapeutic benefits in breast cancer, in part by attenuating tumor-associated angiogenesis and the metastasis-promoting functions of tumor-associated macrophages.

  8. Ganglioside GM2 mediates migration of tumor cells by interacting with integrin and modulating the downstream signaling pathway.

    PubMed

    Kundu, Manjari; Mahata, Barun; Banerjee, Avisek; Chakraborty, Sohini; Debnath, Shibjyoti; Ray, Sougata Sinha; Ghosh, Zhumur; Biswas, Kaushik

    2016-07-01

    The definitive role of ganglioside GM2 in mediating tumor-induced growth and progression is still unknown. Here we report a novel role of ganglioside GM2 in mediating tumor cell migration and uncovered its mechanism. Data shows differential expression levels of GM2-synthase as well as GM2 in different human cancer cells. siRNA mediated knockdown of GM2-synthase in CCF52, A549 and SK-RC-26B cells resulted in significant inhibition of tumor cell migration as well as invasion in vitro without affecting cellular proliferation. Over-expression of GM2-synthase in low-GM2 expressing SK-RC-45 cells resulted in a consequent increase in migration thus confirming the potential role GM2 and its downstream partners play in tumor cell migration and motility. Further, treatment of SK-RC-45 cells with exogenous GM2 resulted in a dramatic increase in migratory and invasive capacity with no change in proliferative capacity, thereby confirming the role of GM2 in tumorigenesis specifically by mediating tumor migration and invasion. Gene expression profiling of GM2-synthase silenced cells revealed altered expression of several genes involved in cell migration primarily those controlling the integrin mediated signaling. GM2-synthase knockdown resulted in decreased phosphorylation of FAK, Src as well as Erk, while over-expression and/or exogenous GM2 treatment caused increased FAK and Erk phosphorylation respectively. Again, GM2 mediated invasion and Erk phosphorylation is blocked in integrin knockdown SK-RC-45 cells, thus confirming that GM2 mediated migration and phosphorylation of Erk is integrin dependent. Finally, confocal microscopy suggested co-localization while co-immunoprecipitation and surface plasmon resonance (SPR) confirmed direct interaction of membrane bound ganglioside, GM2 with the integrin receptor. PMID:27066976

  9. Ganglioside GM2 mediates migration of tumor cells by interacting with integrin and modulating the downstream signaling pathway.

    PubMed

    Kundu, Manjari; Mahata, Barun; Banerjee, Avisek; Chakraborty, Sohini; Debnath, Shibjyoti; Ray, Sougata Sinha; Ghosh, Zhumur; Biswas, Kaushik

    2016-07-01

    The definitive role of ganglioside GM2 in mediating tumor-induced growth and progression is still unknown. Here we report a novel role of ganglioside GM2 in mediating tumor cell migration and uncovered its mechanism. Data shows differential expression levels of GM2-synthase as well as GM2 in different human cancer cells. siRNA mediated knockdown of GM2-synthase in CCF52, A549 and SK-RC-26B cells resulted in significant inhibition of tumor cell migration as well as invasion in vitro without affecting cellular proliferation. Over-expression of GM2-synthase in low-GM2 expressing SK-RC-45 cells resulted in a consequent increase in migration thus confirming the potential role GM2 and its downstream partners play in tumor cell migration and motility. Further, treatment of SK-RC-45 cells with exogenous GM2 resulted in a dramatic increase in migratory and invasive capacity with no change in proliferative capacity, thereby confirming the role of GM2 in tumorigenesis specifically by mediating tumor migration and invasion. Gene expression profiling of GM2-synthase silenced cells revealed altered expression of several genes involved in cell migration primarily those controlling the integrin mediated signaling. GM2-synthase knockdown resulted in decreased phosphorylation of FAK, Src as well as Erk, while over-expression and/or exogenous GM2 treatment caused increased FAK and Erk phosphorylation respectively. Again, GM2 mediated invasion and Erk phosphorylation is blocked in integrin knockdown SK-RC-45 cells, thus confirming that GM2 mediated migration and phosphorylation of Erk is integrin dependent. Finally, confocal microscopy suggested co-localization while co-immunoprecipitation and surface plasmon resonance (SPR) confirmed direct interaction of membrane bound ganglioside, GM2 with the integrin receptor.

  10. X-ray enabled detection and eradication of circulating tumor cells with nanoparticles.

    PubMed

    Hossain, Mainul; Luo, Yang; Sun, Zhaoyong; Wang, Chaoming; Zhang, Minghui; Fu, Hanyu; Qiao, Yong; Su, Ming

    2012-01-01

    The early detection and eradication of circulating tumor cells (CTCs) play an important role in cancer metastasis management. This paper describes a new nanoparticle-enabled technique for integrated enrichment, detection and killing of CTCs by using magnetic nanoparticles and bismuth nanoparticles, X-ray fluorescence spectrometry, and X-ray radiation. The nanoparticles are modified with tumor targeting agents and conjugated with tumor cells through folate receptors over-expressed on cancer cells. A permanent micro-magnet is used to collect CTCs suspended inside a flowing medium that contains phosphate buffered saline (PBS) or whole blood. The characteristic X-ray emissions from collected bismuth nanoparticles, upon excitation with collimated X-rays, are used to detect CTCs. Results show that the method is capable of selectively detecting CTCs at concentrations ranging from 100-100,000 cells/mL in the buffer solution, with a detection limit of ≈ 100 CTCs/mL. Moreover, the dose of primary X-rays can be enhanced to kill the localized CTCs by radiation induced DNA damage, with minimal invasiveness, thus making in vivo personalized CTC management possible.

  11. Anticancer strategies based on the metabolic profile of tumor cells: therapeutic targeting of the Warburg effect

    PubMed Central

    Chen, Xi-sha; Li, Lan-ya; Guan, Yi-di; Yang, Jin-ming; Cheng, Yan

    2016-01-01

    Tumor cells rely mainly on glycolysis for energy production even in the presence of sufficient oxygen, a phenomenon termed the Warburg effect, which is the most outstanding characteristic of energy metabolism in cancer cells. This metabolic adaptation is believed to be critical for tumor cell growth and proliferation, and a number of onco-proteins and tumor suppressors, including the PI3K/Akt/mTOR signaling pathway, Myc, hypoxia-inducible factor and p53, are involved in the regulation of this metabolic adaptation. Moreover, glycolytic cancer cells are often invasive and impervious to therapeutic intervention. Thus, altered energy metabolism is now appreciated as a hallmark of cancer and a promising target for cancer treatment. A better understanding of the biology and the regulatory mechanisms of aerobic glycolysis has the potential to facilitate the development of glycolysis-based therapeutic interventions for cancer. In addition, glycolysis inhibition combined with DNA damaging drugs or chemotherapeutic agents may be effective anticancer strategies through weakening cell damage repair capacity and enhancing drug cytotoxicity. PMID:27374491

  12. 3D culture broadly regulates tumor cell hypoxia response and angiogenesis via pro-inflammatory pathways

    PubMed Central

    DelNero, Peter; Lane, Maureen; Verbridge, Scott S.; Kwee, Brian; Kermani, Pouneh; Hempstead, Barbara; Stroock, Abraham; Fischbach, Claudia

    2015-01-01

    Oxygen status and tissue dimensionality are critical determinants of tumor angiogenesis, a hallmark of cancer and an enduring target for therapeutic intervention. However, it is unclear how these microenvironmental conditions interact to promote neovascularization, due in part to a lack of comprehensive, unbiased data sets describing tumor cell gene expression as a function of oxygen levels within three-dimensional (3D) culture. Here, we utilized alginate-based, oxygen-controlled 3D tumor models to study the interdependence of culture context and the hypoxia response. Microarray gene expression analysis of tumor cells cultured in 2D versus 3D under ambient or hypoxic conditions revealed striking interdependence between culture dimensionality and hypoxia response, which was mediated in part by pro-inflammatory signaling pathways. In particular, interleukin-8 (IL-8) emerged as a major player in the microenvironmental regulation of the hypoxia program. Notably, this interaction between dimensionality and oxygen status via IL-8 increased angiogenic sprouting in a 3D endothelial invasion assay. Taken together, our data suggest that pro-inflammatory pathways are critical regulators of tumor hypoxia response within 3D environments that ultimately impact tumor angiogenesis, potentially providing important therapeutic targets. Furthermore, these results highlight the importance of pathologically relevant tissue culture models to study the complex physical and chemical processes by which the cancer microenvironment mediates new vessel formation. PMID:25934456

  13. Mechanical phenotyping of tumor cells using a microfluidic cell squeezer device

    NASA Astrophysics Data System (ADS)

    Khan, Zeina S.; Kamyabi, Nabiollah; Vanapalli, Siva A.

    2013-03-01

    Studies have indicated that cancer cells have distinct mechanical properties compared to healthy cells. We are investigating the potential of cell mechanics as a biophysical marker for diagnostics and prognosis of cancer. To establish the significance of mechanical properties for cancer diagnostics, a high throughput method is desired. Although techniques such as atomic force microscopy are very precise, they are limited in throughput for cellular mechanical property measurements. To develop a device for high throughput mechanical characterization of tumor cells, we have fabricated a microfludic cell squeezer device that contains narrow micrometer-scale pores. Fluid flow is used to drive cells into these pores mimicking the flow-induced passage of circulating tumor cells through microvasculature. By integrating high speed imaging, the device allows for the simultaneous characterization of five different parameters including the blockage pressure, cell velocity, cell size, elongation and the entry time into squeezer. We have tested a variety of in vitro cell lines, including brain and prostate cancer cell lines, and have found that the entry time is the most sensitive measurement capable of differentiating between cell lines with differing invasiveness.

  14. Type I collagen aging impairs discoidin domain receptor 2-mediated tumor cell growth suppression

    PubMed Central

    Saby, Charles; Buache, Emilie; Brassart-Pasco, Sylvie; El Btaouri, Hassan; Courageot, Marie-Pierre; Van Gulick, Laurence; Garnotel, Roselyne; Jeannesson, Pierre; Morjani, Hamid

    2016-01-01

    Tumor cells are confronted to a type I collagen rich environment which regulates cell proliferation and invasion. Biological aging has been associated with structural changes of type I collagen. Here, we address the effect of collagen aging on cell proliferation in a three-dimensional context (3D). We provide evidence for an inhibitory effect of adult collagen, but not of the old one, on proliferation of human fibrosarcoma HT-1080 cells. This effect involves both the activation of the tyrosine kinase Discoidin Domain Receptor 2 (DDR2) and the tyrosine phosphatase SHP-2. DDR2 and SHP-2 were less activated in old collagen. DDR2 inhibition decreased SHP-2 phosphorylation in adult collagen and increased cell proliferation to a level similar to that observed in old collagen. In the presence of old collagen, a high level of JAK2 and ERK1/2 phosphorylation was observed while expression of the cell cycle negative regulator p21CIP1 was decreased. Inhibition of DDR2 kinase function also led to an increase in ERK1/2 phosphorylation and a decrease in p21CIP1 expression. Similar signaling profile was observed when DDR2 was inhibited in adult collagen. Altogether, these data suggest that biological collagen aging could increase tumor cell proliferation by reducingthe activation of the key matrix sensor DDR2. PMID:27121132

  15. 3D culture broadly regulates tumor cell hypoxia response and angiogenesis via pro-inflammatory pathways.

    PubMed

    DelNero, Peter; Lane, Maureen; Verbridge, Scott S; Kwee, Brian; Kermani, Pouneh; Hempstead, Barbara; Stroock, Abraham; Fischbach, Claudia

    2015-07-01

    Oxygen status and tissue dimensionality are critical determinants of tumor angiogenesis, a hallmark of cancer and an enduring target for therapeutic intervention. However, it is unclear how these microenvironmental conditions interact to promote neovascularization, due in part to a lack of comprehensive, unbiased data sets describing tumor cell gene expression as a function of oxygen levels within three-dimensional (3D) culture. Here, we utilized alginate-based, oxygen-controlled 3D tumor models to study the interdependence of culture context and the hypoxia response. Microarray gene expression analysis of tumor cells cultured in 2D versus 3D under ambient or hypoxic conditions revealed striking interdependence between culture dimensionality and hypoxia response, which was mediated in part by pro-inflammatory signaling pathways. In particular, interleukin-8 (IL-8) emerged as a major player in the microenvironmental regulation of the hypoxia program. Notably, this interaction between dimensionality and oxygen status via IL-8 increased angiogenic sprouting in a 3D endothelial invasion assay. Taken together, our data suggest that pro-inflammatory pathways are critical regulators of tumor hypoxia response within 3D environments that ultimately impact tumor angiogenesis, potentially providing important therapeutic targets. Furthermore, these results highlight the importance of pathologically relevant tissue culture models to study the complex physical and chemical processes by which the cancer microenvironment mediates new vessel formation.

  16. Type I collagen aging impairs discoidin domain receptor 2-mediated tumor cell growth suppression.

    PubMed

    Saby, Charles; Buache, Emilie; Brassart-Pasco, Sylvie; El Btaouri, Hassan; Courageot, Marie-Pierre; Van Gulick, Laurence; Garnotel, Roselyne; Jeannesson, Pierre; Morjani, Hamid

    2016-05-01

    Tumor cells are confronted to a type I collagen rich environment which regulates cell proliferation and invasion. Biological aging has been associated with structural changes of type I collagen. Here, we address the effect of collagen aging on cell proliferation in a three-dimensional context (3D).We provide evidence for an inhibitory effect of adult collagen, but not of the old one, on proliferation of human fibrosarcoma HT-1080 cells. This effect involves both the activation of the tyrosine kinase Discoidin Domain Receptor 2 (DDR2) and the tyrosine phosphatase SHP-2. DDR2 and SHP-2 were less activated in old collagen. DDR2 inhibition decreased SHP-2 phosphorylation in adult collagen and increased cell proliferation to a level similar to that observed in old collagen.In the presence of old collagen, a high level of JAK2 and ERK1/2 phosphorylation was observed while expression of the cell cycle negative regulator p21CIP1 was decreased. Inhibition of DDR2 kinase function also led to an increase in ERK1/2 phosphorylation and a decrease in p21CIP1 expression. Similar signaling profile was observed when DDR2 was inhibited in adult collagen. Altogether, these data suggest that biological collagen aging could increase tumor cell proliferation by reducingthe activation of the key matrix sensor DDR2. PMID:27121132

  17. Development of a Biomimetic Chondroitin Sulfate-modified Hydrogel to Enhance the Metastasis of Tumor Cells

    PubMed Central

    Liu, Yang; Wang, Shujun; Sun, Dongsheng; Liu, Yongdong; Liu, Yang; Wang, Yang; Liu, Chang; Wu, Hao; Lv, Yan; Ren, Ying; Guo, Xin; Sun, Guangwei; Ma, Xiaojun

    2016-01-01

    Tumor metastasis with resistance to anticancer therapies is the main cause of death in cancer patients. It is necessary to develop reliable tumor metastasis models that can closely recapitulate the pathophysiological features of the native tumor tissue. In this study, chondroitin sulfate (CS)-modified alginate hydrogel beads (ALG-CS) are developed to mimic the in vivo tumor microenvironment with an abnormally increased expression of CS for the promotion of tumor cell metastasis. The modification mechanism of CS on alginate hydrogel is due to the cross-linking between CS and alginate molecules via coordination of calcium ions, which enables ALG-CS to possess significantly different physical characteristics than the traditional alginate beads (ALG). And quantum chemistry calculations show that in addition to the traditional egg-box structure, novel asymmetric egg-box-like structures based on the interaction between these two kinds of polymers are also formed within ALG-CS. Moreover, tumor cell metastasis is significantly enhanced in ALG-CS compared with that in ALG, as confirmed by the increased expression of MMP genes and proteins and greater in vitro invasion ability. Therefore, ALG-CS could be a convenient and effective 3D biomimetic scaffold that would be used to construct standardized tumor metastasis models for tumor research and anticancer drug screening. PMID:27432752

  18. Platelets and tumor cells: a new form of border control

    PubMed Central

    Stanger, Ben Z.; Kahn, Mark L.

    2013-01-01

    Tumor metastasis is the primary cause of death due to cancer, but the mechanisms by which tumor cells metastasize remain incompletely understood. In this issue of CancerCell, Schumacher et al. suggest that ATP released from tumor-associated platelets in the blood facilitates tumor metastasis by relaxing endothelial barrier function. PMID:23845439

  19. Modified Bleomycin Disaccharides Exhibiting Improved Tumor Cell Targeting

    PubMed Central

    2015-01-01

    The bleomycins (BLMs) are a family of antitumor antibiotics used clinically for anticancer chemotherapy. Their antitumor selectivity derives at least in part from their ability to target tumor cells, a property that resides in the carbohydrate moiety of the antitumor agent. In earlier studies, we have demonstrated that the tumor cell selectivity resides in the mannose carbamoyl moiety of the BLM saccharide and that both the BLM disaccharide and monosaccharide containing the carbamoyl moiety were capable of the delivery/uptake of a conjugated cyanine dye into cultured cancer cell lines. Presently, the nature of the participation of the carbamoyl moiety has been explored further to provide compounds of utility for defining the nature of the mechanism of tumor cell recognition and uptake by BLM saccharides and in the hope that more efficient compounds could be identified. A library of seven disaccharide–Cy5** dye conjugates was prepared that are structural analogues of the BLM disaccharide. These differed from the natural BLM disaccharide in the position, orientation, and substitution of the carbamoyl group. Studies of these compounds in four matched sets of tumor and normal cell lines revealed a few that were both tumor cell selective and internalized 2–4-fold more efficiently than the natural BLM disaccharide. PMID:25272367

  20. After clouds sun again shines on circulating tumor cells research

    PubMed Central

    Barriere, Guislaine

    2013-01-01

    In the Science issue of first February 2013 Yu M et al. characterized epithelial and mesenchymal circulating tumor cells (CTC) by RNA-in situ hybridization. In this editorial we comment their results and emphasize the different CTC subpopulations arising from epithelial mesenchymal transition (EMT). PMID:25332963

  1. After clouds sun again shines on circulating tumor cells research.

    PubMed

    Barriere, Guislaine; Rigaud, Michel

    2013-07-01

    In the Science issue of first February 2013 Yu M et al. characterized epithelial and mesenchymal circulating tumor cells (CTC) by RNA-in situ hybridization. In this editorial we comment their results and emphasize the different CTC subpopulations arising from epithelial mesenchymal transition (EMT).

  2. Tumor cell vascular mimicry: Novel targeting opportunity in melanoma.

    PubMed

    Hendrix, Mary J C; Seftor, Elisabeth A; Seftor, Richard E B; Chao, Jun-Tzu; Chien, Du-Shieng; Chu, Yi-Wen

    2016-03-01

    In 1999, the American Journal of Pathology published an article, entitled "Vascular channel formation by human melanoma cells in vivo and in vitro: vasculogenic mimicry" by Maniotis and colleagues, which ignited a spirited debate for several years and earned the journal's distinction of a "citation classic" (Maniotis et al., 1999). Tumor cell vasculogenic mimicry (VM), also known as vascular mimicry, describes the plasticity of aggressive cancer cells forming de novo vascular networks and is associated with the malignant phenotype and poor clinical outcome. The tumor cells capable of VM share the commonality of a stem cell-like, transendothelial phenotype, which may be induced by hypoxia. Since its introduction as a novel paradigm for melanoma tumor perfusion, many studies have contributed new findings illuminating the underlying molecular pathways supporting VM in a variety of tumors, including carcinomas, sarcomas, glioblastomas, astrocytomas, and melanomas. Of special significance is the lack of effectiveness of angiogenesis inhibitors on tumor cell VM, suggesting a selective resistance by this phenotype to conventional therapy. Facilitating the functional plasticity of tumor cell VM are key proteins associated with vascular, stem cell, extracellular matrix, and hypoxia-related signaling pathways--each deserving serious consideration as potential therapeutic targets and diagnostic indicators of the aggressive, metastatic phenotype. This review highlights seminal findings pertinent to VM, including the effects of a novel, small molecular compound, CVM-1118, currently under clinical development to target VM, and illuminates important molecular pathways involved in the suppression of this plastic, aggressive phenotype, using melanoma as a model.

  3. Induced Polyploidy in Diploid Ornamental Ginger (Hedychium muluense) Using Colchicine and Oryzalin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ploidy level of H. muluense, a diploid (2n = 2x = 34) and dwarf ornamental ginger species, has been determined and is reported for the first time. Oryzalin and colchicine were successfully used to induce polyploidy in Hedychium muluense in vitro. Embryogenic cell lines were treated with oryzalin...

  4. Differential effects of polyploidy and diploidy on fitness of apomictic Boechera.

    PubMed

    Voigt-Zielinski, Marie-Luise; Piwczyński, Marcin; Sharbel, Timothy F

    2012-06-01

    The co-occurrence of apomixis (asexual reproduction) and polyploidy in plants has been the subject of debate in regard to the origin and evolution of asexuality. In recent years, polyploidy has been postulated as a maintenance and stabilization factor rather than as a source of apomixis origin. It is assumed polyploidy facilitates the compensation for mutation accumulation, and hence, the rare occurrence of diploid apomixis indirectly supports this finding. Nevertheless, diploid apomicts exist and are successful, especially in the genus Boechera. While comparing phenotypic traits, fitness-related traits and apomixis penetrance between both diploid and triploid apomicts in the genus Boechera, it was expected to find trait variance that can be attributed to ploidy. Surprisingly, little trait variation could be assigned to ploidy, but rather trait variations were mainly genotype-specific. Additionally, it is shown that paternal contribution is very important for trait success, even though all offspring are genetically identical to the mother plant. This harbors implications for the introduction of apomixis into crop plants, considering the effects of paternal contribution during asexual reproduction. Nevertheless, polyploidy is an efficient way to buffer deleterious mutations, but the flexibility of diploid apomicts of the genus Boechera for rare sexual events contributes to their success in nature.

  5. Multiple polyploidy events in the early radiation of nodulating and non-nodulating legumes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unresolved questions about evolution of the large and diverse legume family include the timing of polyploidy (whole-genome duplication; WGDs) relative to the origin of the major lineages within the Fabaceae and to the origin of symbiotic nitrogen fixation. Previous work has established that a WGD af...

  6. HAMLET binding to α-actinin facilitates tumor cell detachment.

    PubMed

    Trulsson, Maria; Yu, Hao; Gisselsson, Lennart; Chao, Yinxia; Urbano, Alexander; Aits, Sonja; Mossberg, Ann-Kristin; Svanborg, Catharina

    2011-03-08

    Cell adhesion is tightly regulated by specific molecular interactions and detachment from the extracellular matrix modifies proliferation and survival. HAMLET (Human Alpha-lactalbumin Made LEthal to Tumor cells) is a protein-lipid complex with tumoricidal activity that also triggers tumor cell detachment in vitro and in vivo, suggesting that molecular interactions defining detachment are perturbed in cancer cells. To identify such interactions, cell membrane extracts were used in Far-western blots and HAMLET was shown to bind α-actinins; major F-actin cross-linking proteins and focal adhesion constituents. Synthetic peptide mapping revealed that HAMLET binds to the N-terminal actin-binding domain as well as the integrin-binding domain of α-actinin-4. By co-immunoprecipitation of extracts from HAMLET-treated cancer cells, an interaction with α-actinin-1 and -4 was observed. Inhibition of α-actinin-1 and α-actinin-4 expression by siRNA transfection increased detachment, while α-actinin-4-GFP over-expression significantly delayed rounding up and detachment of tumor cells in response to HAMLET. In response to HAMLET, adherent tumor cells rounded up and detached, suggesting a loss of the actin cytoskeletal organization. These changes were accompanied by a reduction in β1 integrin staining and a decrease in FAK and ERK1/2 phosphorylation, consistent with a disruption of integrin-dependent cell adhesion signaling. Detachment per se did not increase cell death during the 22 hour experimental period, regardless of α-actinin-4 and α-actinin-1 expression levels but adherent cells with low α-actinin levels showed increased death in response to HAMLET. The results suggest that the interaction between HAMLET and α-actinins promotes tumor cell detachment. As α-actinins also associate with signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, additional α-actinin-dependent mechanisms are discussed.

  7. Host epithelial geometry regulates breast cancer cell invasiveness

    PubMed Central

    Boghaert, Eline; Gleghorn, Jason P.; Lee, KangAe; Gjorevski, Nikolce; Radisky, Derek C.; Nelson, Celeste M.

    2012-01-01

    Breast tumor development is regulated in part by cues from the local microenvironment, including interactions with neighboring nontumor cells as well as the ECM. Studies using homogeneous populations of breast cancer cell lines cultured in 3D ECM have shown that increased ECM stiffness stimulates tumor cell invasion. However, at early stages of breast cancer development, malignant cells are surrounded by normal epithelial cells, which have been shown to exert a tumor-suppressive effect on cocultured cancer cells. Here we explored how the biophysical characteristics of the host microenvironment affect the proliferative and invasive tumor phenotype of the earliest stages of tumor development, by using a 3D microfabrication-based approach to engineer ducts composed of normal mammary epithelial cells that contained a single tumor cell. We found that the phenotype of the tumor cell was dictated by its position in the duct: proliferation and invasion were enhanced at the ends and blocked when the tumor cell was located elsewhere within the tissue. Regions of invasion correlated with high endogenous mechanical stress, as shown by finite element modeling and bead displacement experiments, and modulating the contractility of the host epithelium controlled the subsequent invasion of tumor cells. Combining microcomputed tomographic analysis with finite element modeling suggested that predicted regions of high mechanical stress correspond to regions of tumor formation in vivo. This work suggests that the mechanical tone of nontumorigenic host epithelium directs the phenotype of tumor cells and provides additional insight into the instructive role of the mechanical tumor microenvironment. PMID:23150585

  8. The pentose phosphate pathway: an antioxidant defense and a crossroad in tumor cell fate.

    PubMed

    Riganti, Chiara; Gazzano, Elena; Polimeni, Manuela; Aldieri, Elisabetta; Ghigo, Dario

    2012-08-01

    The pentose phosphate pathway, one of the main antioxidant cellular defense systems, has been related for a long time almost exclusively to its role as a provider of reducing power and ribose phosphate to the cell. In addition to this "traditional" correlation, in the past years multiple roles have emerged for this metabolic cascade, involving the cell cycle, apoptosis, differentiation, motility, angiogenesis, and the response to anti-tumor therapy. These findings make the pentose phosphate pathway a very interesting target in tumor cells. This review summarizes the latest discoveries relating the activity of the pentose phosphate pathway to various aspects of tumor metabolism, such as cell proliferation and death, tissue invasion, angiogenesis, and resistance to therapy, and discusses the possibility that drugs modulating the pathway could be used as potential tools in tumor therapy.

  9. Fibroblasts induce epithelial to mesenchymal transition in breast tumor cells which is prevented by fibroblasts treatment with histamine in high concentration.

    PubMed

    Porretti, Juliana C; Mohamad, Nora A; Martín, Gabriela A; Cricco, Graciela P

    2014-06-01

    Epithelial to mesenchymal transition (EMT) of cancer cells is an essential process in cancer progression. Cancer cells that undergone EMT loose cell-cell contacts, acquire mesenchymal properties and develop migratory and invasive abilities. In previous studies we have demonstrated that histamine may modify the invasive phenotype of pancreatic and mammary tumor cells. In this work we proposed to investigate whether histamine may also influence the interaction between tumor cells and normal fibroblasts. The potential activation of normal CCD-1059Sk fibroblasts by histamine and EMT phenotypic changes induced in MCF-7 and MDA-MB-231 breast tumor cells by the conditioned media (CM) derived from fibroblasts were evaluated. Initially, we determined the presence of H1, H2 and H4 histamine receptors and matrix metalloproteinase 2 (MMP2) mRNA in CCD-1059Sk fibroblasts. MMP2 gelatinolytic activity, cell migration and alpha-smooth muscle actin expression were increased in fibroblasts by low doses (<1μM) and decreased by high doses (20μM) of histamine. MCF-7 cells cultured with CM from fibroblasts exhibited spindle-shaped morphology, cell spreading and cytoplasmic expression of β-catenin but there was no change in MMP2 activity and cell migration. MDA-MB-231 cells cultured with CM from fibroblasts showed a more elongated phenotype, cell spreading, cytoplasmic β-catenin, increased MMP2 activity and endogenous TGF-β1 expression, and enhanced cell migration and invasion. Notably, all these features were reversed when mammary tumor cells were cultured with CM from fibroblasts treated with 20μM histamine. In conclusion, high doses of histamine may prevent the activation of fibroblasts and also avert the EMT related changes induced in epithelial tumor cells by fibroblasts CM.

  10. Independent regulation of tumor cell migration by matrix stiffness and confinement

    PubMed Central

    Pathak, Amit; Kumar, Sanjay

    2012-01-01

    Tumor invasion and metastasis are strongly regulated by biophysical interactions between tumor cells and the extracellular matrix (ECM). While the influence of ECM stiffness on cell migration, adhesion, and contractility has been extensively studied in 2D culture, extension of this concept to 3D cultures that more closely resemble tissue has proven challenging, because perturbations that change matrix stiffness often concurrently change cellular confinement. This coupling is particularly problematic given that matrix-imposed steric barriers can regulate invasion speed independent of mechanics. Here we introduce a matrix platform based on microfabrication of channels of defined wall stiffness and geometry that allows independent variation of ECM stiffness and channel width. For a given ECM stiffness, cells confined to narrow channels surprisingly migrate faster than cells in wide channels or on unconstrained 2D surfaces, which we attribute to increased polarization of cell-ECM traction forces. Confinement also enables cells to migrate increasingly rapidly as ECM stiffness rises, in contrast with the biphasic relationship observed on unconfined ECMs. Inhibition of nonmuscle myosin II dissipates this traction polarization and renders the relationship between migration speed and ECM stiffness comparatively insensitive to matrix confinement. We test these hypotheses in silico by devising a multiscale mathematical model that relates cellular force generation to ECM stiffness and geometry, which we show is capable of recapitulating key experimental trends. These studies represent a paradigm for investigating matrix regulation of invasion and demonstrate that matrix confinement alters the relationship between cell migration speed and ECM stiffness. PMID:22689955

  11. Effect of Fe3O4 Nanoparticles on Skin Tumor Cells and Dermal Fibroblasts

    PubMed Central

    Alili, Lirija; Chapiro, Swetlana; Marten, Gernot U.; Schmidt, Annette M.; Zanger, Klaus; Brenneisen, Peter

    2015-01-01

    Iron oxide (Fe3O4) nanoparticles have been used in many biomedical approaches. The toxicity of Fe3O4 nanoparticles on mammalian cells was published recently. Though, little is known about the viability of human cells after treatment with Fe3O4 nanoparticles. Herein, we examined the toxicity, production of reactive oxygen species, and invasive capacity after treatment of human dermal fibroblasts (HDF) and cells of the squamous tumor cell line (SCL-1) with Fe3O4 nanoparticles. These nanoparticles had an average size of 65 nm. Fe3O4 nanoparticles induced oxidative stress via generation of reactive oxygen species (ROS) and subsequent initiation of lipid peroxidation. Furthermore, the question was addressed of whether Fe3O4 nanoparticles affect myofibroblast formation, known to be involved in tumor invasion. Herein, Fe3O4 nanoparticles prevent the expression alpha-smooth muscle actin and therefore decrease the number of myofibroblastic cells. Moreover, our data show in vitro that concentrations of Fe3O4 nanoparticles, which are nontoxic for normal cells, partially reveal a ROS-triggered cytotoxic but also a pro-invasive effect on the fraction of squamous cancer cells surviving the treatment with Fe3O4 nanoparticles. The data herein show that the Fe3O4 nanoparticles appear not to be adequate for use in therapeutic approaches against cancer cells, in contrast to recently published data with cerium oxide nanoparticles. PMID:26090418

  12. Self-assembly synthesis, tumor cell targeting, and photothermal capabilities of antibody-coated indocyanine green nanocapsules.

    PubMed

    Yu, Jie; Javier, David; Yaseen, Mohammad A; Nitin, Nitin; Richards-Kortum, Rebecca; Anvari, Bahman; Wong, Michael S

    2010-02-17

    New colloidal materials that can generate heat upon irradiation are being explored for photothermal therapy as a minimally invasive approach to cancer treatment. The near-infrared dye indocyanine green (ICG) could serve as a basis for such a material, but its encapsulation and subsequent use are difficult to carry out. We report the three-step room-temperature synthesis of approximately 120-nm capsules loaded with ICG within salt-cross-linked polyallylamine aggregates, and coated with antiepidermal growth factor receptor (anti-EGFR) antibodies for tumor cell targeting capability. We studied the synthesis conditions such as temperature and water dilution to control the capsule size and characterized the size distribution via dynamic light scattering and scanning electron microscopy. We further studied the specificity of tumor cell targeting using three carcinoma cell lines with different levels of EGFR expression and investigated the photothermal effects of ICG containing nanocapsules on EGFR-rich tumor cells. Significant thermal toxicity was observed for encapsulated ICG as compared to free ICG at 808 nm laser irradiation with radiant exposure of 6 W/cm(2). These results illustrate the ability to design a colloidal material with cell targeting and heat generating capabilities using noncovalent chemistry.

  13. Enhanced and Differential Capture of Circulating Tumor Cells from Lung Cancer Patients by Microfluidic Assays Using Aptamer Cocktail

    PubMed Central

    Zhao, Libo; Tang, Chuanhao; Xu, Li; Zhang, Zhen; Li, Xiaoyan; Hu, Haixu; Cheng, Si; Zhou, Wei; Huang, Mengfei; Fong, Anna; Liu, Bing; Tseng, Hsian-Rong; Gao, Hongjun; Liu, Yi; Fang, Xiaohong

    2016-01-01

    Collecting circulating tumor cells (CTCs) shed from solid tumor through a minimally invasive approach provides an opportunity to solve a long-standing oncology problem, the real-time monitoring of tumor state and analysis of tumor heterogeneity. However, efficient capture and detection of CTCs with diverse phenotypes is still challenging. In this work, a microfluidic assay is developed using the rationally-designed aptamer cocktails with synergistic effect. Enhanced and differential capture of CTCs for nonsmall cell lung cancer (NSCLC) patients is achieved. It is also demonstrated that the overall consideration of CTC counts obtained by multiple aptamer combinations can provide more comprehensive information in treatment monitoring. PMID:26763166

  14. Characterization of DNA Methylation in Circulating Tumor Cells

    PubMed Central

    Pixberg, Constantin F.; Schulz, Wolfgang A.; Stoecklein, Nikolas H.; Neves, Rui P. L.

    2015-01-01

    Epigenetics contributes to molecular mechanisms leading to tumor cell transformation and systemic progression of cancer. However, the dynamics of epigenetic remodeling during metastasis remains unexplored. In this context, circulating tumor cells (CTCs) might enable a direct insight into epigenetic mechanisms relevant for metastasis by providing direct access to systemic cancer. CTCs can be used as prognostic markers in cancer patients and are regarded as potential metastatic precursor cells. However, despite substantial technical progress, the detection and molecular characterization of CTCs remain challenging, in particular the analysis of DNA methylation. As recent studies have started to address the epigenetic state of CTCs, we discuss here the potential of such investigations to elucidate mechanisms of metastasis and to develop tumor biomarkers. PMID:26506390

  15. Adjuvants for enhancing the immunogenicity of whole tumor cell vaccines.

    PubMed

    Chiang, Cheryl Lai-Lai; Kandalaft, Lana E; Coukos, George

    2011-01-01

    Whole tumor cell lysates can serve as excellent multivalent vaccines for priming tumor-specific CD8(+) and CD4(+) T cells. Whole cell vaccines can be prepared with hypochlorous acid oxidation, UVB-irradiation and repeat cycles of freeze and thaw. One major obstacle to successful immunotherapy is breaking self-tolerance to tumor antigens. Clinically approved adjuvants, including Montanide™ ISA-51 and 720, and keyhole-limpet proteins can be used to enhance tumor cell immunogenicity by stimulating both humoral and cellular anti-tumor responses. Other potential adjuvants, such as Toll-like receptor agonists (e.g., CpG, MPLA and PolyI:C), and cytokines (e.g., granulocyte-macrophage colony stimulating factor), have also been investigated. PMID:21557641

  16. Transport processes in biological systems: Tumoral cells and human brain

    NASA Astrophysics Data System (ADS)

    Lucia, Umberto

    2014-01-01

    The entropy generation approach has been developed for the analysis of complex systems, with particular regards to biological systems, in order to evaluate their stationary states. The entropy generation is related to the transport processes related to exergy flows. Moreover, cancer can be described as an open complex dynamic and self-organizing system. Consequently, it is used as an example useful to evaluate the different thermo-chemical quantities of the transport processes in normal and in tumoral cells systems.

  17. Tumor cell lysates as immunogenic sources for cancer vaccine design

    PubMed Central

    González, Fermín E; Gleisner, Alejandra; Falcón-Beas, Felipe; Osorio, Fabiola; López, Mercedes N; Salazar-Onfray, Flavio

    2015-01-01

    Autologous dendritic cells (DCs) loaded with tumor-associated antigens (TAAs) are a promising immunological tool for cancer therapy. These stimulate the antitumor response and immunological memory generation. Nevertheless, many patients remain refractory to DC approaches. Antigen (Ag) delivery to DCs is relevant to vaccine success, and antigen peptides, tumor-associated proteins, tumor cells, autologous tumor lysates, and tumor-derived mRNA have been tested as Ag sources. Recently, DCs loaded with allogeneic tumor cell lysates were used to induce a potent immunological response. This strategy provides a reproducible pool of almost all potential Ags suitable for patient use, independent of MHC haplotypes or autologous tumor tissue availability. However, optimizing autologous tumor cell lysate preparation is crucial to enhancing efficacy. This review considers the role of cancer cell-derived lysates as a relevant source of antigens and as an activating factor for ex vivo therapeutic DCs capable of responding to neoplastic cells. These promising therapies are associated with the prolonged survival of advanced cancer patients. PMID:25625929

  18. Microvascular Transport and Tumor Cell Adhesion in the Microcirculation

    PubMed Central

    Fu, Bingmei M.; Liu, Yang

    2016-01-01

    One critical step in tumor metastasis is tumor cell adhesion to the endothelium forming the microvessel wall. Understanding this step may lead to new therapeutic concepts for tumor metastasis. Vascular endothelium forming the microvessel wall and the glycocalyx layer at its surface are the principal barriers to, and regulators of the material exchange between circulating blood and body tissues. The cleft between adjacent ECs (interendothelial cleft) is the principal pathway for water and solutes transport through the microvessel wall in health. It is also suggested to be the pathway for high molecular weight plasma proteins, leukocytes and tumor cells across microvessel walls in disease. Thus the first part of the review introduced the mathematical models for water and solutes transport through the interendothelial cleft. These models, combined with the experimental results from in vivo animal studies and electron microscopic observations, are used to evaluate the role of the endothelial surface glycocalyx, the junction strand geometry in the interendothelial cleft, and the surrounding extracellular matrix and tissue cells, as the determinants of microvascular transport. The second part of the review demonstrated how the microvascular permeability, hydrodynamic factors, microvascular geometry and cell adhesion molecules affect tumor cell adhesion in the microcirculation. PMID:22476895

  19. Hyperdiploid tumor cells increase phenotypic heterogeneity within Glioblastoma tumors.

    PubMed

    Donovan, Prudence; Cato, Kathleen; Legaie, Roxane; Jayalath, Rumal; Olsson, Gemma; Hall, Bruce; Olson, Sarah; Boros, Samuel; Reynolds, Brent A; Harding, Angus

    2014-04-01

    Here we report the identification of a proliferative, viable, and hyperdiploid tumor cell subpopulation present within Glioblastoma (GB) patient tumors. Using xenograft tumor models, we demonstrate that hyperdiploid cell populations are maintained in xenograft tumors and that clonally expanded hyperdiploid cells support tumor formation and progression in vivo. In some patient tumorsphere lines, hyperdiploidy is maintained during long-term culture and in vivo within xenograft tumor models, suggesting that hyperdiploidy can be a stable cell state. In other patient lines hyperdiploid cells display genetic drift in vitro and in vivo, suggesting that in these patients hyperdiploidy is a transient cell state that generates novel phenotypes, potentially facilitating rapid tumor evolution. We show that the hyperdiploid cells are resistant to conventional therapy, in part due to infrequent cell division due to a delay in the G₀/G₁ phase of the cell cycle. Hyperdiploid tumor cells are significantly larger and more metabolically active than euploid cancer cells, and this correlates to an increased sensitivity to the effects of glycolysis inhibition. Together these data identify GB hyperdiploid tumor cells as a potentially important subpopulation of cells that are well positioned to contribute to tumor evolution and disease recurrence in adult brain cancer patients, and suggest tumor metabolism as a promising point of therapeutic intervention against this subpopulation. PMID:24448662

  20. Kaposi's sarcoma tumor cells preferentially express Bcl-xL.

    PubMed Central

    Foreman, K. E.; Wrone-Smith, T.; Boise, L. H.; Thompson, C. B.; Polverini, P. J.; Simonian, P. L.; Nunez, G.; Nickoloff, B. J.

    1996-01-01

    Several recently identified proteins such as Bcl-2 and Bcl-x have been found to regulate programmed cell death (i.e., apoptosis). In this report, we examined the levels of expression of proteins that can either prevent apoptosis (i.e., Bcl-2 or the long form of Bcl-x, designated Bcl-x1) or promote apoptosis (i.e., Bax or the short form of Bcl-x, designated Bcl-xs) in proliferating benign and malignant endothelial cells (ECs). In normal skin with quiescent ECs, no detection by immunohistochemical staining was observed for Bcl-xL, Bcl-xs, or Bcl-2. However, in diseased skin samples that feature a prominent angiogenic response such as in psoriasis or pyogenic granulomas, the proliferating ECs markedly overexpressed Bcl-xL, with little to no Bcl-2. In an acquired-immune-deficiency-syndrome-related neoplasm, Kaposi's sarcoma, the spindle-shaped tumor cells also overexpressed Bcl-xL compared with Bcl-2. These in vivo studies were extended in vitro using cultured ECs and Kaposi's sarcoma tumor cells that were examined by flow cytometry and immunoblot analysis. Both cultured ECs and Kaposi's sarcoma tumor cells express significantly higher levels of Bcl-xL than Bcl-2. Such overexpression of cell survival gene products may contribute to prolonging the longevity of EC-derived cells in several different benign and neoplastic skin disorders that are characterized by a prominent angiogenic tissue response. Images Figure 1 Figure 3 PMID:8780384

  1. Microfluidic Device for Studying Tumor Cell Extravasation in Cancer Metastasis

    SciTech Connect

    Lin, Henry K; Thundat, Thomas George; Evans III, Boyd Mccutchen; Datar, Ram H; Reese, Benjamin E; Zheng, Siyang

    2010-01-01

    Metastasis is the process by which cancer spreads to form secondary tumors at downstream locations throughout the body. This uncontrolled spreading is the leading cause of death in patients with epithelial cancers and is the main reason that suppressing and targeting cancer has proven to be so challenging. Tumor cell extravasation is one of the key steps in cancer s progression towards a metastatic state. This occurs when circulating tumor cells found within the blood stream are able to transmigrate through the endothelium lining and basement membrane of the vasculature to form metastatic tumors at secondary sites within the body. Predicting the likelihood of this occurrence in patients, or being able to determine specific markers involved in this process could lead to preventative measures targeting these types of cancer; moreover, this may lead to the discovery of novel anti-metastatic drugs. We have developed a microfluidic device that has shown the extravasation of fluorescently labeled tumor cells across an endothelial cell lined membrane coated with matrigel followed by the formation of colonies. This device provides the advantages of combining a controlled environment, mimicking that found within the body, with real-time monitoring capabilities allowing for the study of these biomarkers and cellular interactions along with other potential mechanisms involved in the process of extravasation.

  2. IL-12 could induce monocytic tumor cells directional differentiation.

    PubMed

    Ma, Ting-Ting; Wu, Bi-Tao; Lin, Yan; Xiong, Hai-Yu; Wang, Qin; Li, Zi-Wei; Cheng, Feng; Tu, Zhi-Guang

    2015-04-01

    Interleukin-12 (IL-12), a member of interleukin family, plays a critical role in immune responses and anti-tumor activity. In this study, the effects of IL-12 on monocytic tumor cell lines differentiation to macrophagocyte and its likely mechanism was investigated. We examined the differentiation markers, morphological and functional changes, and possible mechanism in IL-12-treated THP-1 and U937 cells. It was found that IL-12 could up-regulated macrophage surface marker CD68 and CD11b expression in a time-dependent manner. Morphologically, after IL-12 treatment, THP-1 and U937 cells became round or irregular shape, even stretched many cell membrane protuberances; some cell nuclei became fuzzy or completely disappeared, and the chromatin appeared dense and cordlike. Furthermore, IL-12-induced monocytic tumor cell differentiation was accompanied by the growth arrest with G1-phase accumulation and S-phase reduction; apoptosis increased with anti-apoptosis protein Bcl-2 down-expression and pro-apoptosis protein Fas up-regulation, and enhanced phagocytosis function. The IL-12-induced macrophage differentiation of THP-1 and U937 cells was associated with the up-regulation of c-fms expression and the CSF-1R Tyr 809 site phosphorylation. These findings have revealed that IL-12 could induce monocytic tumor cells directional differentiation into macrophage-like cells, and its mechanism is possible connected with the up-regulation of c-fms expression and the phosphorylation of CSF-1R Tyr-809 site.

  3. [Diagnostic hysteroscopy and risk of peritoneal dissemination of tumor cells].

    PubMed

    Yazbeck, C; Dhainaut, C; Batallan, A; Benifla, J-L; Thoury, A; Madelenat, P

    2005-04-01

    Questions have been raised about the safety of diagnostic hysteroscopy preceding surgical treatment of endometrial carcinoma. Several studies showed that the risk of a positive cytology among patients presenting endometrial adenocarcinoma was increased after diagnostic hysteroscopy, suggesting a peritoneal dissemination of tumor cells due to the exploration. We studied this hypothesis on the basis of a systematic review of the scientific data. Five studies fulfilling inclusion criteria have been selected and have been introduced into a fixed model of meta-analysis. On a total of 756 studied patients, 79 presented a positive peritoneal cytology. The diagnostic hysteroscopy did not increase significantly the risk of abdominal dissemination of tumor cells, the peritoneal cytology being positive among 38 patients in the group having undergone this intervention vs 41 patients in the control group (OR = 1,64; 95% CI: 0,96-2,80). In conclusion, no formal evidence is currently available concerning the role of diagnostic hysteroscopy on the frequency of peritoneal dissemination of tumor cells, or on the vital prognosis of the patients presenting with endometrial carcinoma. From the data available, there is not any reason to avoid diagnostic hysteroscopy in the initial workup of endometrial cancer. PMID:15894211

  4. Filtration parameters influencing circulating tumor cell enrichment from whole blood.

    PubMed

    Coumans, Frank A W; van Dalum, Guus; Beck, Markus; Terstappen, Leon W M M

    2013-01-01

    Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·10(4)∶10(2)∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm(2) track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC.

  5. Filtration Parameters Influencing Circulating Tumor Cell Enrichment from Whole Blood

    PubMed Central

    Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    Filtration can achieve circulating tumor cell (CTC) enrichment from blood. Key parameters such as flow-rate, applied pressure, and fixation, vary largely between assays and their influence is not well understood. Here, we used a filtration system, to monitor these parameters and determine their relationships. Whole blood, or its components, with and without spiked tumor cells were filtered through track-etched filters. We characterize cells passing through filter pores by their apparent viscosity; the viscosity of a fluid that would pass with the same flow. We measured a ratio of 5·104∶102∶1 for the apparent viscosities of 15 µm diameter MDA-231 cells, 10 µm white cells and 90 fl red cells passing through a 5 µm pore. Fixation increases the pressure needed to pass cells through 8 µm pores 25-fold and halves the recovery of spiked tumor cells. Filtration should be performed on unfixed samples at a pressure of ∼10 mbar for a 1 cm2 track-etched filter with 5 µm pores. At this pressure MDA-231 cells move through the filter in 1 hour. If fixation is needed for sample preservation, a gentle fixative should be selected. The difference in apparent viscosity between CTC and blood cells is key in optimizing recovery of CTC. PMID:23658615

  6. Intracellular particle tracking as a tool for tumor cell characterization

    NASA Astrophysics Data System (ADS)

    Li, Yixuan; Schnekenburger, Juergen; Duits, Michael H. G.

    2009-11-01

    We studied the dynamics of two types of intracellular probe particles, ballistically injected latex spheres and endogenous granules, in tumor cell lines of differerent metastatic potential: breast tumor cells (MCF-7 malignant, MCF-10A benign) and pancreas adenocarcinoma (PaTu8988T malignant, PaTu8988S benign). For both tissue types and for both probes, the mean squared displacement (MSD) function measured in the malignant cells was substantially larger than in the benign cells. Only a few cells were needed to characterize the tissue as malignant or benign based on their MSD, since variations in MSD within the same cell line were relatively small. These findings suggest that intracellular particle tracking (IPT) can serve as a simple and reliable method for characterization of cell states obtained from a small amount of cell sample. Mechanical analysis of the same cell lines with atomic force microscopy (AFM) in force-distance mode revealed that AFM could distinguish between the benign and malignant breast cancer cells but not the pancreatic tumor cell lines. This underlines the potential value of IPT as a complementary nanomechanical tool for studying cell-state-dependent mechanical properties.

  7. Single cell molecular recognition of migrating and invading tumor cells using a targeted fluorescent probe to receptor PTPmu.

    PubMed

    Burden-Gulley, Susan M; Qutaish, Mohammed Q; Sullivant, Kristin E; Tan, Mingqian; Craig, Sonya E L; Basilion, James P; Lu, Zheng-Rong; Wilson, David L; Brady-Kalnay, Susann M

    2013-04-01

    Detection of an extracellular cleaved fragment of a cell-cell adhesion molecule represents a new paradigm in molecular recognition and imaging of tumors. We previously demonstrated that probes that recognize the cleaved extracellular domain of receptor protein tyrosine phosphatase mu (PTPmu) label human glioblastoma brain tumor sections and the main tumor mass of intracranial xenograft gliomas. In this article, we examine whether one of these probes, SBK2, can label dispersed glioma cells that are no longer connected to the main tumor mass. Live mice with highly dispersive glioma tumors were injected intravenously with the fluorescent PTPmu probe to test the ability of the probe to label the dispersive glioma cells in vivo. Analysis was performed using a unique three-dimensional (3D) cryo-imaging technique to reveal highly migratory and invasive glioma cell dispersal within the brain and the extent of colabeling by the PTPmu probe. The PTPmu probe labeled the main tumor site and dispersed cells up to 3.5 mm away. The cryo-images of tumors labeled with the PTPmu probe provide a novel, high-resolution view of molecular tumor recognition, with excellent 3D detail regarding the pathways of tumor cell migration. Our data demonstrate that the PTPmu probe recognizes distant tumor cells even in parts of the brain where the blood-brain barrier is likely intact. The PTPmu probe has potential translational significance for recognizing tumor cells to facilitate molecular imaging, a more complete tumor resection and to serve as a molecular targeting agent to deliver chemotherapeutics to the main tumor mass and distant dispersive tumor cells.

  8. Spontaneous rejection of intradermally transplanted non-engineered tumor cells by neutrophils and macrophages from syngeneic strains of mice.

    PubMed

    Ibata, Minenori; Takahashi, Takeshi; Shimizu, Tetsunosuke; Inoue, Yoshihiro; Maeda, Shogo; Tashiro-Yamaji, Junko; Okada, Masashi; Ueda, Koichi; Kubota, Takahiro; Yoshida, Ryotaro

    2011-10-01

    It is not surprising that tumors arising spontaneously are rarely rejected by T cells, because in general they lack molecules to elicit a primary T-cell response. In fact, cytokine-engineered tumors can induce granulocyte infiltration leading to tumor rejection. In the present study, we i.d. injected seven kinds of non-engineered tumor cells into syngeneic strains of mice. Three of them (i.e. B16, KLN205, and 3LL cells) continued to grow, whereas four of them (i.e. Meth A, I-10, CL-S1, and FM3A cells) were spontaneously rejected after transient growth or without growth. In contrast to the i.d. injection of B16 cells into C57BL/6 mice, which induces infiltration of TAMs into the tumors, the i.d. injection of Meth A cells into BALB/c mice induced the invasion of cytotoxic inflammatory cells, but not of TAMs, into or around the tumors leading to an IFN-γ-dependent rejection. On day 5, the cytotoxic activity against the tumor cells reached a peak; and the effector cells were found to be neutrophils and macrophages. The i.d. Meth A or I-10 cell-immunized, but not non-immunized, mice rejected i.p.- or i.m.-transplanted Meth A or I-10 cells without growth, respectively. The main effector cells were CTLs; and there was no cross-sensitization between these two kinds of tumor cells, suggesting specific rejection of tumor cells by CTLs from i.d. immunized mice. These results indicate that infiltration of cytotoxic myeloid cells (i.e. neutrophils and macrophages, but not TAMs) into or around tumors is essential for their IFN-γ-dependent spontaneous rejection.

  9. Single cell molecular recognition of migrating and invading tumor cells using a targeted fluorescent probe to receptor PTPmu.

    PubMed

    Burden-Gulley, Susan M; Qutaish, Mohammed Q; Sullivant, Kristin E; Tan, Mingqian; Craig, Sonya E L; Basilion, James P; Lu, Zheng-Rong; Wilson, David L; Brady-Kalnay, Susann M

    2013-04-01

    Detection of an extracellular cleaved fragment of a cell-cell adhesion molecule represents a new paradigm in molecular recognition and imaging of tumors. We previously demonstrated that probes that recognize the cleaved extracellular domain of receptor protein tyrosine phosphatase mu (PTPmu) label human glioblastoma brain tumor sections and the main tumor mass of intracranial xenograft gliomas. In this article, we examine whether one of these probes, SBK2, can label dispersed glioma cells that are no longer connected to the main tumor mass. Live mice with highly dispersive glioma tumors were injected intravenously with the fluorescent PTPmu probe to test the ability of the probe to label the dispersive glioma cells in vivo. Analysis was performed using a unique three-dimensional (3D) cryo-imaging technique to reveal highly migratory and invasive glioma cell dispersal within the brain and the extent of colabeling by the PTPmu probe. The PTPmu probe labeled the main tumor site and dispersed cells up to 3.5 mm away. The cryo-images of tumors labeled with the PTPmu probe provide a novel, high-resolution view of molecular tumor recognition, with excellent 3D detail regarding the pathways of tumor cell migration. Our data demonstrate that the PTPmu probe recognizes distant tumor cells even in parts of the brain where the blood-brain barrier is likely intact. The PTPmu probe has potential translational significance for recognizing tumor cells to facilitate molecular imaging, a more complete tumor resection and to serve as a molecular targeting agent to deliver chemotherapeutics to the main tumor mass and distant dispersive tumor cells. PMID:22987116

  10. Induction of protein tyrosine phosphorylation in macrophages incubated with tumor cells.

    PubMed

    Sodhi, A; Shrivastava, A; Kumar, R

    1995-03-01

    The cellular and molecular interaction between monocyte/macrophage and tumor cells leading to macrophage activation is not clearly understood. Since protein tyrosine phosphorylation appears to be a major intracellular signalling event, we checked whether the tumor cells alter tyrosine phosphorylation of proteins in macrophages. We found that both L929 and Yac-1 tumor cells induced increased tyrosine phosphorylation of several polypeptides in peritoneal as well as P388D-1 and IC-21 macrophages. Macrophages co-cultured with tumor cells also showed increased fluorescence with anti-phosphotyrosine-FITC antibody. These observations suggest that increased tyrosine phosphorylation plays a role in tumor cell-induced activation of macrophages. PMID:7539664

  11. Evolutionary history of two divergent Dmrt1 genes reveals two rounds of polyploidy origins in gibel carp.

    PubMed

    Li, Xi-Yin; Zhang, Xiao-Juan; Li, Zhi; Hong, Wei; Liu, Wei; Zhang, Jun; Gui, Jian-Fang

    2014-09-01

    Polyploidy lineages, despite very rare in vertebrates, have been proposed to play significant role in speciation and evolutionary success, but the occurrence history and consequences are still largely unknown. In this study, we used the conserved Dmrt1 to analyze polyploidy occurrence and evolutionary process in polyploid gibel carp. We identified two divergent Dmrt1 genes and respectively localized the two genes on three homologous chromosomes. Subsequently, the corresponding full-length cDNAs and genomic sequences of Dmrt1 genes were also characterized from the closely related species including Carassius auratus auratus and Cyprinus carpio, and their two Dmrt1 genes were respectively localized on two homologous chromosomes. Significantly, the evolutionary relationship analyses among cDNA and genomic DNA sequences of these Dmrt1 genes revealed two rounds of polyploidy origins in the gibel carp: an early polyploidy might result in an common tetraploid ancestor of Carassius auratus gibelio, Carassius auratus auratus and Cyprinus carpio before 18.49 million years ago (Mya), and an late polyploidy might occur from evolutionary branch of Carassius auratus at around 0.51 Mya, which lead to the occurrence of the hexaploid gibel carp. Therefore, this study provides clear genetic evidence for understanding occurrence time and historical process of polyploidy in polyploid vertebrates.

  12. Influence of preharvest tumor cell contamination in bone marrow or blood does not predict resultant tumor cell contamination of granulocyte colony-stimulating factor mobilized stem cells.

    PubMed

    Krüger, W; Kröger, N; Tögel, F; Badbaran, A; Renges, H; Gieseking, F; Gutensohn, K; Jänicke, F; Zander, A R

    2001-04-01

    Tumor cell contamination of stem cell collections harvested from breast cancer patients is a common phenomenon described by several investigators but with findings that vary among reports. Although so-called co-mobilization of these cells has been hypothesized, the origin of tumor cell contamination in stem cells is still unknown. A total of 47 G-CSF mobilized stem cell grafts from patients with nodal-positive (n = 30), chemosensitive metastatic (n = 11), and 5 women with inflammatory breast cancer were evaluated for cancer cells by immunocytochemistry. Additionally, 40 bone marrow aspirations and 23 peripheral blood samples collected prior to apheresis and after one to two cycles of conventional chemotherapy were available for examination. Tumor cell contamination of leukapheresis correlated best with preharvest blood state. This was valid when the nominal (positive/negative) presence of tumor cells in blood was compared to the nominal presence of tumor cells in apheresis samples and when the it was correlated to the tumor cell load of apheresis samples (TCL = tumor cells per 10(6) nucleated cells investigated). The correlation between blood and stem cells was better (nominal and quantitative) than that between marrow and stem cells, despite the larger sample size of marrow aspirations. The presence or absence of cancer cells in apheresis samples could not be safely predicted by the presence or absence of tumor cells in marrow or blood alone. Diagnostic specificity seems to improve from a combination of results from marrow and blood analysis. No correlation was found in quantitative analysis of tumor cell contamination between marrow and blood. In conclusion, the results suggest that blood and bone marrow represent different compartments for epithelial cancer cells and that contaminating tumor cells in stem cell harvests may be derived from the blood and/or marrow compartment. The tumor cell contamination of a stem cell harvest cannot be safely predicted by a

  13. A Comparative Epigenomic Analysis of Polyploidy-Derived Genes in Soybean and Common Bean1[OPEN

    PubMed Central

    Kim, Kyung Do; El Baidouri, Moaine; Abernathy, Brian; Iwata-Otsubo, Aiko; Chavarro, Carolina; Gonzales, Michael; Libault, Marc; Grimwood, Jane; Jackson, Scott A.

    2015-01-01

    Soybean (Glycine max) and common bean (Phaseolus vulgaris) share a paleopolyploidy (whole-genome duplication [WGD]) event, approximately 56.5 million years ago, followed by a genus Glycine-specific polyploidy, approximately 10 million years ago. Cytosine methylation is an epigenetic mark that plays an important role in the regulation of genes and transposable elements (TEs); however, the role of DNA methylation in the fate/evolution of genes following polyploidy and speciation has not been fully explored. Whole-genome bisulfite sequencing was used to produce nucleotide resolution methylomes for soybean and common bean. We found that, in soybean, CG body-methylated genes were abundant in WGD genes, which were, on average, more highly expressed than single-copy genes and had slower evolutionary rates than unmethylated genes, suggesting that WGD genes evolve more slowly than single-copy genes. CG body-methylated genes were also enriched in shared single-copy genes (single copy in both species) that may be responsible for the broad and high expression patterns of this class of genes. In addition, diverged methylation patterns in non-CG contexts between paralogs were due mostly to TEs in or near genes, suggesting a role for TEs and non-CG methylation in regulating gene expression post polyploidy. Reference methylomes for both soybean and common bean were constructed, providing resources for investigating epigenetic variation in legume crops. Also, the analysis of methylation patterns of duplicated and single-copy genes has provided insights into the functional consequences of polyploidy and epigenetic regulation in plant genomes. PMID:26149573

  14. Transforming potential and matrix stiffness co-regulate confinement sensitivity of tumor cell migration

    PubMed Central

    Pathak, Amit

    2013-01-01

    It is now well established that tumor cell invasion through tissue is strongly regulated by the microstructural and mechanical properties of the extracellular matrix (ECM). However, it remains unclear how these physical microenvironmental inputs are jointly processed with oncogenic lesions to drive invasion. In this study, we address this open question by combining a microfabricated polyacrylamide channel (μPAC) platform that enables independent control of ECM stiffness and confinement with an isogenically-matched breast tumor progression series in which the oncogenes ErbB2 and 14-3-3ζ are overexpressed independently or in tandem. We find that increasing channel confinement and overexpressing ErbB2 both promote cell migration to a similar degree when other parameters are kept constant. In contrast, 14-3-3ζ overexpression slows migration speed, and does so in a fashion that dwarfs effects of ECM confinement and stiffness. We also find that ECM stiffness dramatically enhances cell motility when combined with ErbB2 overexpression, demonstrating that biophysical cues and cell-intrinsic parameters promote cell invasion in an integrative manner. Morphometric analysis of cells inside the μPAC platform reveals that the rapid cell migration induced by narrow channels and ErbB2 overexpression both are accompanied by increased cell polarization. Disruption of this polarization by pharmacological inhibition of Rac GTPase phenocopies 14-3-3ζ overexpression by reducing cell polarization and slowing migration. By systematically measuring migration speed as a function of matrix stiffness and confinement, we also quantify for the first time the sensitivity of migration speed to microchannel properties and transforming potential. These results demonstrate that oncogenic lesions and ECM biophysical properties can synergistically interact to drive invasive migration, and that both inputs may act through common molecular mechanisms to enhance migration speed. PMID:23832051

  15. Passive Entrapment of Tumor Cells Determines Metastatic Dissemination to Spinal Bone and Other Osseous Tissues.

    PubMed

    Broggini, Thomas; Piffko, Andras; Hoffmann, Christian J; Harms, Christoph; Vajkoczy, Peter; Czabanka, Marcus

    2016-01-01

    During the metastatic process tumor cells circulate in the blood stream and are carried to various organs. In order to spread to different organs tumor cell-endothelial cell interactions are crucial for extravasation mechanisms. It remains unclear if tumor cell dissemination to the spinal bone occurs by passive entrapment of circulating tumor cells or by active cellular mechanisms mediated by cell surface molecules or secreted factors. We investigated the seeding of three different tumor cell lines (melanoma, lung and prostate carcinoma) to the microvasculature of different organs. Their dissemination was compared to biologically passive microbeads. The spine and other organs were resected three hours after intraarterial injection of tumor cells or microbeads. Ex vivo homogenization and fluorescence analysis allowed quantification of tumor cells or microbeads in different organs. Interestingly, tumor cell distribution to the spinal bone was comparable to dissemination of microbeads independent of the tumor cell type (melanoma: 5.646% ± 7.614%, lung: 6.007% ± 1.785%, prostate: 3.469% ± 0.602%, 7 μm beads: 9.884% ± 7.379%, 16 μm beads: 7.23% ± 1.488%). Tumor cell seeding differed significantly between tumor cells and microbeads in all soft tissue organs. Moreover, there were significant differences between the different tumor cell lines in their dissemination behaviour to soft tissue organs only. These findings demonstrate that metastatic dissemination of tumor cells to spinal bone and other osseous organs is mediated by passive entrapment of tumor cells similar to passive plugging of microvasculature observed after intraarterial microbeads injection. PMID:27603673

  16. Determination by flow cytometry polyploidy inducing-capacity of colchicine in Cajanus cajan (L.) Mill sp.

    PubMed

    Udensi, O U; Ontui, V

    2013-07-01

    The need to optimize flow cytometric analysis for the determination of ploidy level is a worthwhile venture to precisely know at what concentration of a mutagen and at what time of exposure polyploidy could be induced. Flow cytometry was used to determine the polyploidy inducing-capacity of colchicine in pigeon pea (Cajanus cajan (L.) Mill sp). Seeds of pigeon pea were soaked in three different concentrations of colchicine-5 mg, 10 and 15 mg L(-1) for 24, 48 and 72 h, respectively, while the control group was soaked in water. Treated seeds and those from the control were planted in a greenhouse using a Completely Randomized Design (CRD). Results show that colchicine induced tetraploids (4n) and mixoploids (2n+ 4n) as the concentration of colchicine increased and soaking duration. Days to seedling emergence increased as concentration of colchicine and duration of soaking increased while germination rate decreased proportionately with the increase in colchicine concentration and soaking duration but did not significantly affect percentage seedling survival. Explicitly, colchicine has the capacity of inducing polyploidy; especially tetraploids on the seeds of pigeon pea, which obviously could be harnessed for further breeding and improvement of the pigeon pea. PMID:24505986

  17. Expression partitioning between genes duplicated by polyploidy under abiotic stress and during organ development.

    PubMed

    Liu, Zhenlan; Adams, Keith L

    2007-10-01

    Allopolyploidy has been a prominent mode of speciation and a recurrent process during plant evolution and has contributed greatly to the large number of duplicated genes in plant genomes [1-4]. Polyploidy often leads to changes in genome organization and gene expression [5-9]. The expression of genes that are duplicated by polyploidy (termed homeologs) can be partitioned between the duplicates so that one copy is expressed and functions only in some organs and the other copy is expressed only in other organs, indicative of subfunctionalization [10]. To determine how homeologous-gene expression patterns change during organ development and in response to abiotic stress conditions, we have examined expression of the alcohol dehydrogenase gene AdhA in allopolyploid cotton (Gossypium hirsutum). Expression ratios of the two homeologs vary considerably during the development of organs from seedlings and fruits. Abiotic stress treatments, including cold, dark, and water submersion, altered homeologous-gene expression. Most notably, only one copy is expressed in hypocotyls during a water-submersion treatment, and only the other copy is expressed during cold stress. These results imply that subfunctionalization of genes duplicated by polyploidy has occurred in response to abiotic stress conditions. Partitioning of duplicate gene expression in response to environmental stress may lead to duplicate gene retention during subsequent evolution. PMID:17825563

  18. The metabolic interactions between tumor cells and tumor-associated stroma (TAS) in prostatic cancer.

    PubMed

    Giatromanolaki, Alexandra; Koukourakis, Michael I; Koutsopoulos, Anastasios; Mendrinos, Savvas; Sivridis, Efthimios

    2012-11-01

    Tumor-associated stroma (TAS) is not simply a supporting element for cancer cells, but plays an important role in tumor growth, invasion and metastasis. Changes on the level of stromal constituents, such as loss of Caveolin-1 and increased thymidine phosphorylase (TP) expression, have been associated with tumor aggressiveness. The mutual cooperation between stromal fibroblasts and cancer cells is another distinguishing feature, which has recently emerged. In this investigation, both the loss of Caveolin-1 and the increased TP expression in the prostatic TAS was associated with high Gleason score (p = 0.0002 and 0.003, respectively); the two proteins were acting both independently and synergistically. In addition, TP was significantly associated with high stromal Ki-67 (MIB1) proliferation index (p = 0.03). Analysis of the metabolic interactions between stromal and epithelial elements showed that, while prostatic cancer cells express principally (> 91%) lactate dehydrogenase-5 (LDH-5) (anaerobic metabolism), the tumor-associated fibroblasts/myofibroblasts (TAFs) express largely (67.8%) LDH-1 (aerobic metabolism)-the terms TAFs and TAS are used interchangeably. These two isoenzyme pathways act complementary; the LDH-5 pathway converts pyruvate to lactate, whereas the LDH-1 enzyme system utilizes the secreted metabolite lactate to produce pyruvate, essential for continuous energy supply to tumor cells. Monocarboxylate transporter-1 (MCT-1)-the main facilitator of lactate uptake in tumor cells, was expressed exclusively in prostate cancer cells and related directly to LDH-5 overexpression. These findings support and extend our previous studies on energy recycling between the aerobic stroma and the anaerobic cancer cells within the framework of Warburg effect.

  19. The Ultrasound effects on non tumoral cell line at 1 MHz therapeutic frequency

    NASA Astrophysics Data System (ADS)

    Di Giambattista, L.; Grimaldi, P.; Udroiu, I.; Pozzi, D.; Cinque, G.; Frogley, M. D.; Cassarà, A. M.; Bedini, A.; Giliberti, C.; Palomba, R.; Buogo, S.; Giansanti, A.; Congiu Castellano, A.

    2011-02-01

    The aim of this research is to investigate some bioeffects due to Therapeutic Ultrasound (1 MHz and 50tumoral cells. Ultrasound (US) has been demonstrated to alter the cell membrane permeability due to a biophysical mechanism, Sonoporation, and exploited as a promising non-invasive gene transfer method. We have used the NIH-3T3 cell line as a model system and exposed it to US medical equipment for 15, 30, 45, 60 minutes at distances of 10 and 15 cm from the source transducer, corresponding to the far field region where cm. We have worked with the maximum power in pulsed system with 75% duty cycle. Characterization of the unfocused, planar and with a circular geometry 1 MHz source transducer, was performed and the acoustics pressure was measured by a calibrated 0.5 mm needle hydrophone; moreover, the pressure field generated by the source transducer was simulated. The US effects on cells were assessed by Fourier transform infrared (FTIR) Imaging with focal plane array (FPA) detector. By the IR analysis, the US exposure on non tumoral cells has induced a change of the intensity for CH2 asymmetric stretching (2924 cm-1) band in the lipid region (3000-2800 cm-1) that it could detect an energy-dependent process. It has already shown that cells invest energy to catalyze lipid movement in order to maintain a specific transmembrane phospholipid distribution. Although asymmetry is the rule for control cells, the loss of asymmetry could be associated with the permeability change of plasma membrane inducing temporary pores.

  20. Diagnostic Applications and Methods to Isolate Circulating Tumor Cells (CTCs) from Blood

    NASA Astrophysics Data System (ADS)

    Tang, Cha-Mei

    2013-03-01

    Each year a million new cancer cases are diagnosed in the United States. Ninety percent of the deaths will be the result of metastasis, not from the primary tumor. Tissue biopsy is a universally accepted tool for cancer diagnosis and determination of treatment. The procedure varies, but is invasive, costly, and can be fatal, and for these reasons is seldom repeated after initial diagnosis. Monitoring of treatment response and for possible relapse is usually done by CT or MRI scan, both of which are expensive and require the tumor to change size perceptibly. Further, cancer can mutate or develop resistance to therapeutics and require modification of the treatment regimen. The initial tissue biopsy often cannot reflect the disease as it progresses, requiring new biopsy samples to determine a change of treatment. All carcinomas, about 80% of all cancer, shed tumor cells into the circulation, most often at the later stages when treatment is more critical. These circulating tumor cells (CTCs) are the cause of metastasis, and can be isolated from patient blood to serve as ``liquid biopsy''. These CTCs contain a valuable trove of information that help both patient and clinician understand disease status. In addition to counting the number of CTCs (known to be a prognostic indicator of survival), CTCs can provide biomarker information such as protein expressions and gene mutations, amplifications, and translocations. This information can be used to determine treatment. During treatment, the number of intact and apoptotic CTCs can be measured on a repeated basis to measure the patient's response to treatment and disease progression. Following treatment, liquid biopsy can be repeated at regular intervals to watch for relapse. Methods to isolate CTCs can be grouped into three categories: i) immunocapture based on surface markers of CTCs, ii) size exclusion based on CTC size, typically larger than blood cells, and iii) negative selection utilizing red blood cell lysis, white

  1. Simultaneous Detection of Disseminated and Circulating Tumor Cells in Primary Breast Cancer Patients

    PubMed Central

    Hartkopf, Andreas D.; Wallwiener, Markus; Hahn, Markus; Fehm, Tanja N.; Brucker, Sara Y.; Taran, Florin-Andrei

    2016-01-01

    Purpose Disseminated tumor cells (DTCs) from bone marrow (BM) are a surrogate of minimal residual disease (MRD) in primary breast cancer (PBC) patients and associated with an adverse prognosis. However, BM sampling is an invasive procedure. Although there is growing evidence that circulating tumor cells (CTCs) from the blood are also suitable for monitoring MRD, data on the simultaneous detection of DTCs and CTCs are limited. Materials and Methods We determined the presence of DTCs using immunocytochemistry and the pan-cytokeratin antibody A45-B/B3. CTCs were determined simultaneously using a reverse transcription-polymerase chain reaction–based assay (AdnaTest Breast Cancer) and CellSearch (at least one CTC per 7.5 mL blood). We compared the detection of DTCs and CTCs and evaluated their impact on disease-free and overall survival. Results Of 585 patients, 131 (22%) were positive for DTCs; 19 of 202 (9%) and 18 of 383 (5%) patients were positive for CTCs, as shown by AdnaTest and CellSearch, respectively. No significant association was observed between DTCs and CTCs (p=0.248 and p=0.146 as shown by AdnaTest and CellSearch, respectively). The presence of DTCs (p=0.046) and the presence of CTCs as shown by CellSearch (p=0.007) were predictive of disease-free survival. Conclusion Our data confirm the prognostic relevance of DTCs and CTCs in patients with PBC. As we found no significant relationship between DTCs and CTCs, prospective trials should include their simultaneous detection. Within those trials, the question of whether or not DTCs and CTCs are independent subpopulations of malignant cell clones should be determined by molecular characterization. PMID:25687853

  2. Probing the compressibility of tumor cell nuclei by combined atomic force-confocal microscopy.

    PubMed

    Krause, Marina; Te Riet, Joost; Wolf, Katarina

    2013-12-01

    The cell nucleus is the largest and stiffest organelle rendering it the limiting compartment during migration of invasive tumor cells through dense connective tissue. We here describe a combined atomic force microscopy (AFM)-confocal microscopy approach for measurement of bulk nuclear stiffness together with simultaneous visualization of the cantilever-nucleus contact and the fate of the cell. Using cantilevers functionalized with either tips or beads and spring constants ranging from 0.06-10 N m(-1), force-deformation curves were generated from nuclear positions of adherent HT1080 fibrosarcoma cell populations at unchallenged integrity, and a nuclear stiffness range of 0.2 to 2.5 kPa was identified depending on cantilever type and the use of extended fitting models. Chromatin-decondensating agent trichostatin A (TSA) induced nuclear softening of up to 50%, demonstrating the feasibility of our approach. Finally, using a stiff bead-functionalized cantilever pushing at maximal system-intrinsic force, the nucleus was deformed to 20% of its original height which after TSA treatment reduced further to 5% remaining height confirming chromatin organization as an important determinant of nuclear stiffness. Thus, combined AFM-confocal microscopy is a feasible approach to study nuclear compressibility to complement concepts of limiting nuclear deformation in cancer cell invasion and other biological processes.

  3. Probing the compressibility of tumor cell nuclei by combined atomic force-confocal microscopy

    NASA Astrophysics Data System (ADS)

    Krause, Marina; te Riet, Joost; Wolf, Katarina

    2013-12-01

    The cell nucleus is the largest and stiffest organelle rendering it the limiting compartment during migration of invasive tumor cells through dense connective tissue. We here describe a combined atomic force microscopy (AFM)-confocal microscopy approach for measurement of bulk nuclear stiffness together with simultaneous visualization of the cantilever-nucleus contact and the fate of the cell. Using cantilevers functionalized with either tips or beads and spring constants ranging from 0.06-10 N m-1, force-deformation curves were generated from nuclear positions of adherent HT1080 fibrosarcoma cell populations at unchallenged integrity, and a nuclear stiffness range of 0.2 to 2.5 kPa was identified depending on cantilever type and the use of extended fitting models. Chromatin-decondensating agent trichostatin A (TSA) induced nuclear softening of up to 50%, demonstrating the feasibility of our approach. Finally, using a stiff bead-functionalized cantilever pushing at maximal system-intrinsic force, the nucleus was deformed to 20% of its original height which after TSA treatment reduced further to 5% remaining height confirming chromatin organization as an important determinant of nuclear stiffness. Thus, combined AFM-confocal microscopy is a feasible approach to study nuclear compressibility to complement concepts of limiting nuclear deformation in cancer cell invasion and other biological processes.

  4. Detection of Circulating Tumor Cells by Fluorescent Immunohistochemistry in Patients with Esophageal Squamous Cell Carcinoma: Potential Clinical Applications

    PubMed Central

    Li, Shu-Ping; Guan, Quan-Lin; Zhao, Da; Pei, Guang-Jun; Su, Hong-Xin; Du, Lan-Ning; He, Jin-Xiang; Liu, Zhao-Chen

    2016-01-01

    Background Circulating tumor cells (CTCs) are tumor cells that leave the primary tumor site and enter the bloodstream, where they can spread to other organs; they are very important in the diagnosis, treatment, and prognosis of malignant tumors. However, few studies have investigated CTCs in esophageal squamous cell carcinoma (ESCC). The aim of this study was to investigate the CTCs in blood of ESCC patients and its potential relevance to clinicopathological features and prognosis. Material/Methods CTCs were acquired by a negative enrichment method that used magnetic activated cell sorting (MACSTM). Fluorescent immunohistochemistry (IHC) was used to identify the CTCs. Then, the positive CTC patients with ESCC were analyzed, after which the relationship between CTCs and clinicopathologic features was evaluated. Results In the present study, 62 out of 140 (44.3%) patients with ESCC were positive for CTCs. The positive rate of CTCs was significantly related with stage of ESCC patients (P=0.013). However, there was no relationship between CTC status and age, sex, smoking tumor history, tumor location, differentiation of tumor, lymphatic invasion, or lymph venous invasion (P>0.05). Kaplan-Meier analysis showed that patients positive for CTCs had significantly shorter survival time than patients negative for CTCs. Multivariate analysis demonstrated that stage and CTC status were significant prognostic factors for patients with ESCC. Conclusions CTCs positivity is an independent prognostic biomarker that indicates a worse prognosis for patients with ESCC. PMID:27184872

  5. Ceramide Kinase Promotes Tumor Cell Survival and Mammary Tumor Recurrence

    PubMed Central

    Payne, Ania W.; Pant, Dhruv K.; Pan, Tien-chi; Chodosh, Lewis A.

    2014-01-01

    Recurrent breast cancer is typically an incurable disease and, as such, is disproportionately responsible for deaths from this disease. Recurrent breast cancers arise from the pool of disseminated tumor cells (DTCs) that survive adjuvant or neoadjuvant therapy, and patients with detectable DTCs following therapy are at substantially increased risk for recurrence. Consequently, the identification of pathways that contribute to the survival of breast cancer cells following therapy could aid in the development of more effective therapies that decrease the burden of residual disease and thereby reduce the risk of breast cancer recurrence. We now report that Ceramide Kinase (Cerk) is required for mammary tumor recurrence following HER2/neu pathway inhibition and is spontaneously up-regulated during tumor recurrence in multiple genetically engineered mouse models for breast cancer. We find that Cerk is rapidly up-regulated in tumor cells following HER2/neu down-regulation or treatment with Adriamycin and that Cerk is required for tumor cell survival following HER2/neu down-regulation. Consistent with our observations in mouse models, analysis of gene expression profiles from over 2,200 patients revealed that elevated CERK expression is associated with an increased risk of recurrence in women with breast cancer. Additionally, although CERK expression is associated with aggressive subtypes of breast cancer, including those that are ER–, HER2+, basal-like, or high grade, its association with poor clinical outcome is independent of these clinicopathological variables. Together, our findings identify a functional role for Cerk in breast cancer recurrence and suggest the clinical utility of agents targeted against this pro-survival pathway. PMID:25164007

  6. Correlation of proliferative and clonogenic tumor cells in multiple myeloma

    SciTech Connect

    Karp, J.E.; Burke, P.J.; Saylor, P.L.; Humphrey, R.L.

    1984-09-01

    To expand on the findings from previous clinical trials that the growth of residual tumor is increased at a predictable time following initial drug administration, malignant plasma cells from bone marrows of patients with multiple myeloma (MM) were examined for changes in proliferation and clonogenicity induced in vivo by cyclophosphamide and in vitro by drug-induced humoral stimulatory activity. Peak plasma cell (/sup 3/H)thymidine labeling index (LI) occurred predictably following drug and paralleled changes in agar colony formation by marrow cells obtained during therapy. Colony-forming capacity of pretreatment MM marrow populations was enhanced when those cells were cultured with humoral stimulatory activity, similar to the increased colony formation detected in Day 9 postcyclophosphamide marrows at the time of peak plasma cell LI. To further define a relationship between proliferative plasma cells and colony-forming tumor cells, MM marrows were fractionated by sedimentation on an isokinetic gradient. Enrichment of a proliferative tumor cell cohort was achieved, evidenced by (/sup 3/H)thymidine LI. Colony-forming cells were also enriched by isokinetic gradient sedimentation, and agar colony formation by MM marrow cell fractions correlated with the kinetic characteristics of the isolated subpopulations. These studies of whole and fractionated human MM marrow cell populations suggest that the kinetically active cells which are induced to proliferate in vivo and in vitro are closely related to the clonogenic tumor cells which produce colonies in agar and which, like those cells measured by (/sup 3/H)thymidine LI, respond to growth stimulation by drug-induced humoral stimulatory activity.

  7. P97/CDC-48: proteostasis control in tumor cell biology.

    PubMed

    Fessart, Delphine; Marza, Esther; Taouji, Saïd; Delom, Frédéric; Chevet, Eric

    2013-08-28

    P97/CDC-48 is a prominent member of a highly evolutionary conserved Walker cassette - containing AAA+ATPases. It has been involved in numerous cellular processes ranging from the control of protein homeostasis to membrane trafficking through the intervention of specific accessory proteins. Expression of p97/CDC-48 in cancers has been correlated with tumor aggressiveness and prognosis, however the precise underlying molecular mechanisms remain to be characterized. Moreover p97/CDC-48 inhibitors were developed and are currently under intense investigation as anticancer drugs. Herein, we discuss the role of p97/CDC-48 in cancer development and its therapeutic potential in tumor cell biology.

  8. Passive Entrapment of Tumor Cells Determines Metastatic Dissemination to Spinal Bone and Other Osseous Tissues

    PubMed Central

    Piffko, Andras; Hoffmann, Christian J.; Harms, Christoph; Vajkoczy, Peter; Czabanka, Marcus

    2016-01-01

    During the metastatic process tumor cells circulate in the blood stream and are carried to various organs. In order to spread to different organs tumor cell—endothelial cell interactions are crucial for extravasation mechanisms. It remains unclear if tumor cell dissemination to the spinal bone occurs by passive entrapment of circulating tumor cells or by active cellular mechanisms mediated by cell surface molecules or secreted factors. We investigated the seeding of three different tumor cell lines (melanoma, lung and prostate carcinoma) to the microvasculature of different organs. Their dissemination was compared to biologically passive microbeads. The spine and other organs were resected three hours after intraarterial injection of tumor cells or microbeads. Ex vivo homogenization and fluorescence analysis allowed quantification of tumor cells or microbeads in different organs. Interestingly, tumor cell distribution to the spinal bone was comparable to dissemination of microbeads independent of the tumor cell type (melanoma: 5.646% ± 7.614%, lung: 6.007% ± 1.785%, prostate: 3.469% ± 0.602%, 7 μm beads: 9.884% ± 7.379%, 16 μm beads: 7.23% ± 1.488%). Tumor cell seeding differed significantly between tumor cells and microbeads in all soft tissue organs. Moreover, there were significant differences between the different tumor cell lines in their dissemination behaviour to soft tissue organs only. These findings demonstrate that metastatic dissemination of tumor cells to spinal bone and other osseous organs is mediated by passive entrapment of tumor cells similar to passive plugging of microvasculature observed after intraarterial microbeads injection. PMID:27603673

  9. The Challenges of Detecting Circulating Tumor Cells in Sarcoma.

    PubMed

    Tellez-Gabriel, Marta; Brown, Hannah K; Young, Robin; Heymann, Marie-Françoise; Heymann, Dominique

    2016-01-01

    Sarcomas are a heterogeneous group of malignant neoplasms of mesenchymal origin, many of which have a propensity to develop distant metastases. Cancer cells that have escaped from the primary tumor are able to invade into surrounding tissues, to intravasate into the bloodstream to become circulating tumor cells (CTCs), and are responsible for the generation of distant metastases. Due to the rarity of these tumors and the absence of specific markers expressed by sarcoma tumor cells, the characterization of sarcoma CTCs has to date been relatively limited. Current techniques for isolating sarcoma CTCs are based on size criteria, the identification of circulating cells that express either common mesenchymal markers, sarcoma-specific markers, such as CD99, CD81, or PAX3, and chromosomal translocations found in certain sarcoma subtypes, such as EWS-FLI1 in Ewing's sarcoma, detection of osteoblast-related genes, or measurement of the activity of specific metabolic enzymes. Further studies are needed to improve the isolation and characterization of sarcoma CTCs, to demonstrate their clinical significance as predictive and/or prognostic biomarkers, and to utilize CTCs as a tool for investigating the metastatic process in sarcoma and to identify novel therapeutic targets. The present review provides a short overview of the most recent literature on CTCs in sarcoma. PMID:27656422

  10. The Challenges of Detecting Circulating Tumor Cells in Sarcoma

    PubMed Central

    Tellez-Gabriel, Marta; Brown, Hannah K.; Young, Robin; Heymann, Marie-Françoise; Heymann, Dominique

    2016-01-01

    Sarcomas are a heterogeneous group of malignant neoplasms of mesenchymal origin, many of which have a propensity to develop distant metastases. Cancer cells that have escaped from the primary tumor are able to invade into surrounding tissues, to intravasate into the bloodstream to become circulating tumor cells (CTCs), and are responsible for the generation of distant metastases. Due to the rarity of these tumors and the absence of specific markers expressed by sarcoma tumor cells, the characterization of sarcoma CTCs has to date been relatively limited. Current techniques for isolating sarcoma CTCs are based on size criteria, the identification of circulating cells that express either common mesenchymal markers, sarcoma-specific markers, such as CD99, CD81, or PAX3, and chromosomal translocations found in certain sarcoma subtypes, such as EWS-FLI1 in Ewing’s sarcoma, detection of osteoblast-related genes, or measurement of the activity of specific metabolic enzymes. Further studies are needed to improve the isolation and characterization of sarcoma CTCs, to demonstrate their clinical significance as predictive and/or prognostic biomarkers, and to utilize CTCs as a tool for investigating the metastatic process in sarcoma and to identify novel therapeutic targets. The present review provides a short overview of the most recent literature on CTCs in sarcoma. PMID:27656422

  11. Identification of peptides that bind to irradiated pancreatic tumor cells

    SciTech Connect

    Huang Canhui; Liu, Xiang Y.; Rehemtulla, Alnawaz; Lawrence, Theodore S. . E-mail: tsl@med.umich.edu

    2005-08-01

    Purpose: Peptides targeting tumor vascular cells or tumor cells themselves have the potential to be used as vectors for delivering either DNA in gene therapy or antitumor agents in chemotherapy. We wished to determine if peptides identified by phage display could be used to target irradiated pancreatic cancer cells. Methods and Materials: Irradiated Capan-2 cells were incubated with 5 x 10{sup 12} plaque-forming units of a phage display library. Internalized phage were recovered and absorbed against unirradiated cells. After five such cycles of enrichment, the recovered phage were subjected to DNA sequencing analysis and synthetic peptides made. The binding of both phage and synthetic peptides was evaluated by fluorescence staining and flow cytometry in vitro and in vivo. Results: We identified one 12-mer peptide (PA1) that binds to irradiated Capan-2 pancreatic adenocarcinoma cells but not to unirradiated cells. The binding of peptide was significant after 48 h incubation with cells. In vivo experiments with Capan-2 xenografts in nude mice demonstrated that these small peptides are able to penetrate tumor tissue after intravenous injections and bind specifically to irradiated tumor cells. Conclusion: These data suggest that peptides can be identified that target tumors with radiation-induced cell markers and may be clinically useful.

  12. Silicon Micropore based Electromechanical Transducer to Differentiate Tumor Cells

    NASA Astrophysics Data System (ADS)

    Ali, Waqas; Raza, Muhammad U.; Khanzada, Raja R.; Kim, Young-Tae; Iqbal, Samir M.

    2015-03-01

    Solid-state micropores have been used before to differentiate cancer cells from normal cells using size-based filtering. Tumor cells differ from normal ones not only in size but also in physical properties like elasticity, shape, motility etc. Tumor cells show different physical attributes depending on the stage and type of cancer. We report a micropore based electromechanical transducer that differentiated cancer cells based on their mechanophysical properties. The device was interfaced with a high-speed patch-clamp measurement system that biased the ionic solution across the silicon-based membrane. The bias resulted in the flow of ionic current. Electrical pulses were generated when cells passed through. Different cells depicted characteristic pulses. Translocation profiles of cells that were either small or were more elastic and flexible caused electrical pulses shorter in widths and amplitudes whereas cells with larger size or lesser elasticity/flexibility showed deeper and wider pulses. Three non-small cell lung cancer (NSCLC) cell lines NCI-H1155, A549 and NCI-H460 were successfully differentiated. NCI-H1155, due to their comparatively smaller size, were found quickest in translocating through. The solid-sate micropore based electromechanical transducer could process the whole blood sample of cancer patient without any pre-processing requirements and is ideal for point-of-care applications. Support Acknowledged from NSF through ECCS-1201878.

  13. Hedgehog signaling in myofibroblasts directly promotes prostate tumor cell growth†

    PubMed Central

    Domenech, Maribella; Bjerregaard, Robert; Bushman, Wade; Beebe, David J.

    2012-01-01

    Despite strong evidence for the involvement of the stroma in Hedgehog signaling, little is known about the identity of the stromal cells and the signaling mechanisms that mediate the growth promoting effect of Hh signaling. We developed an in vitro co-culture model using microchannel technology to examine the effect of paracrine Hh signaling on proliferation of prostate cancer cells. We show here that activation of Hh signaling in myofibroblasts is sufficient to accelerate tumor cell growth. This effect was independent of any direct effect of Hh ligand on tumor cells or other cellular components of the tumor stroma. Further, the trophic effect of Hh pathway activation in myofibroblasts does not require collaboration of other elements of the stroma or direct physical interaction with the cancer cells. By isolating the tropic effect of Hh pathway activation in prostate stroma, we have taken the first step toward identifying cell-specific mechanisms that mediate the effect of paracrine Hh signaling on tumor growth. PMID:22234342

  14. Isolation and characterization of circulating tumor cells in prostate cancer

    PubMed Central

    Diamond, Elan; Lee, Guang Yu; Akhtar, Naveed H.; Kirby, Brian J.; Giannakakou, Paraskevi; Tagawa, Scott T.; Nanus, David M.

    2012-01-01

    Circulating tumor cells (CTCs) are tumor cells found in the peripheral blood that putatively originate from established sites of malignancy and likely have metastatic potential. Analysis of CTCs has demonstrated promise as a prognostic marker as well as a source of identifying potential targets for novel therapeutics. Isolation and characterization of these cells for study, however, remain challenging owing to their rarity in comparison with other cellular components of the peripheral blood. Several techniques that exploit the unique biochemical properties of CTCs have been developed to facilitate their isolation. Positive selection of CTCs has been achieved using microfluidic surfaces coated with antibodies against epithelial cell markers or tumor-specific antigens such as EpCAM or prostate-specific membrane antigen (PSMA). Following isolation, characterization of CTCs may help guide clinical decision making. For instance, molecular and genetic characterization may shed light on the development of chemotherapy resistance and mechanisms of metastasis without the need for a tissue biopsy. This paper will review novel isolation techniques to capture CTCs from patients with advanced prostate cancer, as well as efforts to characterize the CTCs. We will also review how these analyzes can assist in clinical decision making. Conclusion: The study of CTCs provides insight into the molecular biology of tumors of prostate origin that will eventually guide the development of tailored therapeutics. These advances are predicated on high yield and accurate isolation techniques that exploit the unique biochemical features of these cells. PMID:23087897

  15. Porous biodegradable EW62 medical implants resist tumor cell growth.

    PubMed

    Hakimi, O; Ventura, Y; Goldman, J; Vago, R; Aghion, E

    2016-04-01

    Magnesium alloys have been widely investigated for biodegradable medical applications. However, the shielding of harmful cells (eg. bacteria or tumorous cells) from immune surveillance may be compounded by the increased porosity of biodegradable materials. We previously demonstrated the improved corrosion resistance and mechanical properties of a novel EW62 (Mg-6%Nd-2%Y-0.5%Zr)) magnesium alloy by rapid solidification followed by extrusion (RS) compared to its conventional counterpart (CC). The present in vitro study evaluated the influence of rapid solidification on cytotoxicity to murine osteosarcoma cells. We found that CC and RS corrosion extracts significantly reduced cell viability over a 24-h exposure period. Cell density was reduced over 48 h following direct contact on both CC and RS surfaces, but was further reduced on the CC surface. The direct presence of cells accelerated corrosion for both materials. The corroded RS material exhibited superior mechanical properties relative to the CC material. The data show that the improved corrosion resistance of the rapidly solidified EW62 alloy (RS) resulted in a relatively reduced cytotoxic effect on tumorous cells. Hence, the tested alloy in the form of a rapidly solidified substance may introduce a good balance between its biodegradation characteristics and cytotoxic effect towards cancerous and normal cells. PMID:26838879

  16. Cancer procoagulant in human tumor cells: evidence from melanoma patients.

    PubMed

    Donati, M B; Gambacorti-Passerini, C; Casali, B; Falanga, A; Vannotti, P; Fossati, G; Semeraro, N; Gordon, S G

    1986-12-01

    It has repeatedly been proposed that fibrin plays a role in tumor growth and metastasis. Among tumor cell products or activities which may promote clot formation, cancer procoagulant (CP), a direct activator of coagulation factor X, has been suggested to be selectively associated with the malignant phenotype. We report here the enzymatic and immunological identification of this cysteine proteinase procoagulant in extracts and cells from human melanoma. CP activity was independent of both the intrinsic and extrinsic pathways of blood coagulation, using factor IX and factor VII deficient plasmas, and was inhibited by the cysteine proteinase inhibitors iodoacetamide and HgCl2. CP activity was detectable in extracts and cell suspensions from all 32 patients studied and was higher in extracts from metastases (14.8 +/- 3.9 units/mg protein) than from the primary tumors (3.7 +/- 1.0 units/mg protein). CP activity was not affected by an anti-apoprotein III antibody or by concanavalin A, a known inhibitor of thromboplastin. In contrast, no CP activity or antigen was detected in extracts from six benign melanocytic lesions. The procoagulant activity was dependent on factor VII and was inhibited by anti-apoprotein III antibody and by concanavalin A, properties that suggest that the procoagulant was tissue thromboplastin. These data indicate that CP can be expressed by human tumor cells and that, among melanotic lesions, its presence is associated with the malignant phenotype and its activity is particularly high in metastatic cells.

  17. The Challenges of Detecting Circulating Tumor Cells in Sarcoma

    PubMed Central

    Tellez-Gabriel, Marta; Brown, Hannah K.; Young, Robin; Heymann, Marie-Françoise; Heymann, Dominique

    2016-01-01

    Sarcomas are a heterogeneous group of malignant neoplasms of mesenchymal origin, many of which have a propensity to develop distant metastases. Cancer cells that have escaped from the primary tumor are able to invade into surrounding tissues, to intravasate into the bloodstream to become circulating tumor cells (CTCs), and are responsible for the generation of distant metastases. Due to the rarity of these tumors and the absence of specific markers expressed by sarcoma tumor cells, the characterization of sarcoma CTCs has to date been relatively limited. Current techniques for isolating sarcoma CTCs are based on size criteria, the identification of circulating cells that express either common mesenchymal markers, sarcoma-specific markers, such as CD99, CD81, or PAX3, and chromosomal translocations found in certain sarcoma subtypes, such as EWS-FLI1 in Ewing’s sarcoma, detection of osteoblast-related genes, or measurement of the activity of specific metabolic enzymes. Further studies are needed to improve the isolation and characterization of sarcoma CTCs, to demonstrate their clinical significance as predictive and/or prognostic biomarkers, and to utilize CTCs as a tool for investigating the metastatic process in sarcoma and to identify novel therapeutic targets. The present review provides a short overview of the most recent literature on CTCs in sarcoma.

  18. Genetic engineering of platelets to neutralize circulating tumor cells.

    PubMed

    Li, Jiahe; Sharkey, Charles C; Wun, Brittany; Liesveld, Jane L; King, Michael R

    2016-04-28

    Mounting experimental evidence demonstrates that platelets support cancer metastasis. Within the circulatory system, platelets guard circulating tumor cells (CTCs) from immune elimination and promote their arrest at the endothelium, supporting CTC extravasation into secondary sites. Neutralization of CTCs in blood circulation can potentially attenuate metastases to distant organs. Therefore, extensive studies have explored the blockade of platelet-CTC interactions as an anti-metastatic strategy. Such an intervention approach, however, may cause bleeding disorders since the platelet-CTC interactions inherently rely on the blood coagulation cascade including platelet activation. On the other hand, platelets have been genetically engineered to correct inherited bleeding disorders in both animal models and human clinical trials. In this study, inspired by the physical association between platelets and CTCs, platelets were genetically modified to express surface-bound tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a cytokine known to induce apoptosis specifically in tumor cells. The TRAIL-expressing platelets were demonstrated to kill cancer cells in vitro and significantly reduce metastases in a mouse model of prostate cancer metastasis. Our results suggest that using platelets to produce and deliver cancer-specific therapeutics can provide a Trojan-horse strategy of neutralizing CTCs to attenuate metastasis.

  19. Let-7 Sensitizes KRAS Mutant Tumor Cells to Chemotherapy

    PubMed Central

    Dai, Xin; Jiang, Ying; Tan, Chalet

    2015-01-01

    KRAS is the most commonly mutated oncogene in human cancers and is associated with poor prognosis and drug resistance. Let-7 is a family of tumor suppressor microRNAs that are frequently suppressed in solid tumors, where KRAS mutations are highly prevalent. In this study, we investigated the potential use of let-7 as a chemosensitizer. We found that let-7b repletion selectively sensitized KRAS mutant tumor cells to the cytotoxicity of paclitaxel and gemcitabine. Transfection of let-7b mimic downregulated the expression of mutant but not wild-type KRAS. Combination of let-7b mimic with paclitaxel or gemcitabine diminished MEK/ERK and PI3K/AKT signaling concurrently, triggered the onset of apoptosis, and reverted the epithelial-mesenchymal transition in KRAS mutant tumor cells. In addition, let-7b repletion downregulated the expression of β-tubulin III and ribonucleotide reductase subunit M2, two proteins known to mediate tumor resistance to paclitaxel and gemcitabine, respectively. Let-7 may represent a new class of chemosensitizer for the treatment of KRAS mutant tumors. PMID:25946136

  20. Dynamic visualization the whole process of cytotoxic T lymphocytes killing the B16 tumor cells in vitro

    NASA Astrophysics Data System (ADS)

    Qi, Shuhong; Zhang, Zhihong

    2016-03-01

    Cytotoxic T lymphocytes (CTLs) played a key role in the immune system to destroy the tumor cells. Although some mechanisms of CTLs killing the tumor cells are revealed already, the dynamic information of CTLs interaction with tumor cells are still not known very clearly. Here we used confocal microscopy to visualize the whole process of CTLs killing the tumor cells in vitro. The imaging data showed that CTLs destroyed the target tumor cells rapidly and efficiently. Several CTLs surrounded one or some tumor cells and the average time for CTLs destroying one tumor cell is just a few minutes in vitro. The study displayed the temporal events of CTLs interacting with tumor cells at the beginning and finally killing them and directly presented the efficient tumor cell cytotoxicity of the CTLs. The results helped us to deeply understand the mechanism of the CTLs destroying the tumor cells and to develop the cancer immunotherapy.

  1. High Specificity in Circulating Tumor Cell Identification Is Required for Accurate Evaluation of Programmed Death-Ligand 1

    PubMed Central

    Schultz, Zachery D.; Warrick, Jay W.; Guckenberger, David J.; Pezzi, Hannah M.; Sperger, Jamie M.; Heninger, Erika; Saeed, Anwaar; Leal, Ticiana; Mattox, Kara; Traynor, Anne M.; Campbell, Toby C.; Berry, Scott M.; Beebe, David J.; Lang, Joshua M.

    2016-01-01

    Background Expression of programmed-death ligand 1 (PD-L1) in non-small cell lung cancer (NSCLC) is typically evaluated through invasive biopsies; however, recent advances in the identification of circulating tumor cells (CTCs) may be a less invasive method to assay tumor cells for these purposes. These liquid biopsies rely on accurate identification of CTCs from the diverse populations in the blood, where some tumor cells share characteristics with normal blood cells. While many blood cells can be excluded by their high expression of CD45, neutrophils and other immature myeloid subsets have low to absent expression of CD45 and also express PD-L1. Furthermore, cytokeratin is typically used to identify CTCs, but neutrophils may stain non-specifically for intracellular antibodies, including cytokeratin, thus preventing accurate evaluation of PD-L1 expression on tumor cells. This holds even greater significance when evaluating PD-L1 in epithelial cell adhesion molecule (EpCAM) positive and EpCAM negative CTCs (as in epithelial-mesenchymal transition (EMT)). Methods To evaluate the impact of CTC misidentification on PD-L1 evaluation, we utilized CD11b to identify myeloid cells. CTCs were isolated from patients with metastatic NSCLC using EpCAM, MUC1 or Vimentin capture antibodies and exclusion-based sample preparation (ESP) technology. Results Large populations of CD11b+CD45lo cells were identified in buffy coats and stained non-specifically for intracellular antibodies including cytokeratin. The amount of CD11b+ cells misidentified as CTCs varied among patients; accounting for 33–100% of traditionally identified CTCs. Cells captured with vimentin had a higher frequency of CD11b+ cells at 41%, compared to 20% and 18% with MUC1 or EpCAM, respectively. Cells misidentified as CTCs ultimately skewed PD-L1 expression to varying degrees across patient samples. Conclusions Interfering myeloid populations can be differentiated from true CTCs with additional staining criteria

  2. Triple combination of irradiation, chemotherapy (pemetrexed), and VEGFR inhibition (SU5416) in human endothelial and tumor cells

    SciTech Connect

    Bischof, Marc; Abdollahi, Amir; Gong Ping; Stoffregen, Clemens; Lipson, Kenneth E.; Debus, Juergen; Weber, Klaus J.; Huber, Peter E. . E-mail: p.huber@dkfz.de

    2004-11-15

    Purpose: This is the first preclinical report evaluating a trimodal therapy consisting of irradiation, chemotherapy, and antiangiogenesis in the context of a multimodal anticancer strategy. The combination of the folate antimetabolite pemetrexed, SU5416, a receptor tyrosine kinase inhibitor of VEGFR2, and irradiation was investigated in human endothelial cells and tumor cell lines. Methods and materials: Primary isolated human umbilical vein endothelial cells (HUVEC), human dermal microvascular endothelial cells (HDMEC), and human glioblastoma (U87) and prostate cancer cells (PC3) were exposed to pemetrexed (2 h) alone and in combination with SU5416 (2 h). When combined with irradiation up to 8 Gy, fixed concentrations of pemetrexed (1.06 {mu}M) and SU5416 (1.0 {mu}M) were used. Proliferation and clonogenic assays were conducted with endothelial and tumor cells. The migration/invasion ability of endothelial cells and the ability to produce tubular structures were tested in Matrigel and tube formation assays. Apoptosis was measured by sub-G1 DNA and caspase-3 flow cytometry. To investigate underlying cell signaling, immunocytochemistry was used to detect Akt survival signaling involvement. Results: Triple combination using only a low-toxicity drug exposure of pemetrexed and SU5416 results in greater response than each treatment alone or than each combination of two modalities in all tested endothelial and tumor cell models. Triple combination substantially inhibits proliferation, migration/invasion, tube formation, and clonogenic survival. Triple combination also induced the highest rate of apoptosis in HDMEC and HUVEC as indicated by sub-1 G1 and caspase-3 assessment. Interestingly, triple combination therapy also reduces proliferation and clonogenic survival significantly in U87 and PC3 tumor cell lines. SU5416 potently inhibited Akt phosphorylation which could be induced by radiation and radiochemotherapy in human endothelial cells. Conclusions: Our findings

  3. In vitro regulation of pericellular proteolysis in prostatic tumor cells treated with bombesin.

    PubMed

    Festuccia, C; Guerra, F; D'Ascenzo, S; Giunciuglio, D; Albini, A; Bologna, M

    1998-01-30

    Bombesin is a potent inducer of signal trasduction pathways involved in the proliferation and invasion of androgen-insensitive prostatic tumor cells. This study examines the bombesin-mediated modulation of pericellular proteolysis, monitoring cell capability to migrate and invade basement membranes, using a chemo-invasion assay and analyzing protease production. The results suggest that bombesin could modulate the invasive potential of prostatic cell lines regulating secretion and cell-surface uptake of uPA and MMP-9 activation. In fact, in PC3 and DU145 cells but not in LNCaP cells, urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) are induced by bombesin treatment. Bombesin also stimulates cell proliferation and this effect can be inhibited blocking uPA by antibodies and/or uPA inhibitor p-aminobenzamidine. Moreover, HMW-uPA induces cell proliferation in LNCaP cells, which do not produce uPA in the basal conditions, while PC3 and DU145 cell growth is supported by autocrine production of uPA. The increment of uPA activity on the external plasma membrane causes an increased pericellular plasmin activation. This effect is inhibited by antibodies against uPA and by p-aminobenzamidine. Similarly to EGF, bombesin stimulates secretion and activation of MMP-9 and TIMP-1 production. MMP-9 activation can be also obtained by HMW-uPA treatment, suggesting that plasma-membrane-bound uPA can start a proteolytic cascade involving MMP-9. Therefore, in in vitro assays, bombesin is able to modulate pericellular proteolysis and cell proliferation, differently distributing and activating proteolytic activities. This effect can be related to the "non-random" degradation of the extracellular matrix in which membrane uPA-uPAreceptor complexes could start bombesin-induced directional protein degradation during metastatic spread. PMID:9455804

  4. HAMLET kills tumor cells by apoptosis: structure, cellular mechanisms, and therapy.

    PubMed

    Gustafsson, Lotta; Hallgren, Oskar; Mossberg, Ann-Kristin; Pettersson, Jenny; Fischer, Walter; Aronsson, Annika; Svanborg, Catharina

    2005-05-01

    New cancer treatments should aim to destroy tumor cells without disturbing normal tissue. HAMLET (human alpha-lactalbumin made lethal to tumor cells) offers a new molecular approach to solving this problem, because it induces apoptosis in tumor cells but leaves normal differentiated cells unaffected. After partial unfolding and binding to oleic acid, alpha-lactalbumin forms the HAMLET complex, which enters tumor cells and freezes their metabolic machinery. The cells proceed to fragment their DNA, and they disintegrate with apoptosis-like characteristics. HAMLET kills a wide range of malignant cells in vitro and maintains this activity in vivo in patients with skin papillomas. In addition, HAMLET has striking effects on human glioblastomas in a rat xenograft model. After convection-enhanced delivery, HAMLET diffuses throughout the brain, selectively killing tumor cells and controlling tumor progression without apparent tissue toxicity. HAMLET thus shows great promise as a new therapeutic with the advantage of selectivity for tumor cells and lack of toxicity.

  5. Tumor-Related Methylated Cell-Free DNA and Circulating Tumor Cells in Melanoma

    PubMed Central

    Salvianti, Francesca; Orlando, Claudio; Massi, Daniela; De Giorgi, Vincenzo; Grazzini, Marta; Pazzagli, Mario; Pinzani, Pamela

    2016-01-01

    Solid tumor release into the circulation cell-free DNA (cfDNA) and circulating tumor cells (CTCs) which represent promising biomarkers for cancer diagnosis. Circulating tumor DNA may be studied in plasma from cancer patients by detecting tumor specific alterations, such as genetic or epigenetic modifications. Ras association domain family 1 isoform A (RASSF1A) is a tumor suppressor gene silenced by promoter hypermethylation in a variety of human cancers including melanoma. The aim of the present study was to assess the diagnostic performance of a tumor-related methylated cfDNA marker in melanoma patients and to compare this parameter with the presence of CTCs. RASSF1A promoter methylation was quantified in cfDNA by qPCR in a consecutive series of 84 melanoma patients and 68 healthy controls. In a subset of 68 cases, the presence of CTCs was assessed by a filtration method (Isolation by Size of Epithelial Tumor Cells, ISET) as well as by an indirect method based on the detection of tyrosinase mRNA by RT-qPCR. The distribution of RASSF1A methylated cfDNA was investigated in cases and controls and the predictive capability of this parameter was assessed by means of the area under the ROC curve (AUC). The percentage of cases with methylated RASSF1A promoter in cfDNA was significantly higher in each class of melanoma patients (in situ, invasive and metastatic) than in healthy subjects (Pearson chi-squared test, p < 0.001). The concentration of RASSF1A methylated cfDNA in the subjects with a detectable quantity of methylated alleles was significantly higher in melanoma patients than in controls. The biomarker showed a good predictive capability (in terms of AUC) in discriminating between melanoma patients and healthy controls. This epigenetic marker associated to cfDNA did not show a significant correlation with the presence of CTCs, but, when the two parameters are jointly considered, we obtain a higher sensitivity of the detection of positive cases in invasive and

  6. Gene modification of primary tumor cells for active immunotherapy of human breast and ovarian cancer.

    PubMed

    Philip, R; Clary, B; Brunette, E; Kilinski, L; Murugesh, D; Sorich, M; Yau, J; Lebkowski, J; Lyerly, H K; Philip, M

    1996-01-01

    We have previously shown that cationic liposomes facilitate adeno-associated virus (AAV) plasmid transfections of primary and cultured cell types. To test the clinical feasibility of using genetically modified tumor vaccines for the treatment of breast and ovarian cancers, we have constructed an expression plasmid pMP6IL2 and investigated the use of liposome-mediated gene delivery into primary, uncultured human breast and ovarian tumor cells to produce interleukin 2 (IL-2)-secreting tumor cells. We have demonstrated significant levels of IL-2 expression in tumor cell lines and primary breast and ovarian tumor cells using this AAV-based expression plasmid complexed to cationic liposomes. Transfections with the non-AAV plasmid containing the identical expression cassette as the AAV plasmid induced IL-2 expression in the tumor cell line but failed to produce IL-2 in primary tumor cells. Significant levels of IL-2 were induced with the AAV plasmid regardless of liposome compositions used for transfection. The transfected breast cell line and primary tumor cells were able to express the transgene product for up to 28 days after lethal radiation. The transfection efficiency was comparable for both the tumor cell line and primary tumor cells and ranged from 20 to 50% for both cell types as assessed by intracellular IL-2 staining. Although the primary tumor cell preparations consist of mixed population of cells, at least 40% of the tumor cells expressed the transgene as assessed by immunostaining for IL-2. The ability to efficiently express transgenes in freshly isolated, nondividing tumor cells may potentiate active immunotherapy strategies for gene-based cancer treatment.

  7. Amplification of mouse mammary tumor virus genomes in non-mammary tumor cells.

    PubMed Central

    Racevskis, J; Beyer, H

    1989-01-01

    Extra proviral copies of mouse mammary tumor virus (MMTV) are known to be present in the genomes of certain T-cell lymphomas of mice. Analysis of additional non-mammary tumor cell types known to express MMTV transcripts and antigens revealed the presence of extra acquired MMTV proviruses in a pituitary tumor cell line, a macrophage line, and Leydig testicular tumor cells. The nature of the amplified MMTV proviruses in these various tumor cell types differed with regard to copy number and presence of alterations in the long terminal repeat region. Images PMID:2535749

  8. Apoptosis as a mechanism of cytolysis of tumor cells by a pathogenic free-living amoeba.

    PubMed

    Alizadeh, H; Pidherney, M S; McCulley, J P; Niederkorn, J Y

    1994-04-01

    Previous studies have shown that trophozoites of the pathogenic free-living amoeba Acanthamoeba castellanii rapidly lysed a variety of tumor cells in vitro. Tumor cells undergoing parasite-mediated lysis displayed characteristic cell membrane blebbing reminiscent of apoptosis. The present investigation examined the role of apoptosis (programmed cell death) in Acanthamoeba-mediated tumor cell lysis. The results showed that more than 70% of tumor cell DNA was fragmented following exposure to Acanthamoeba cell extracts. By contrast, only 7% of untreated control cells underwent DNA fragmentation. DNA fragmentation increased significantly in a dose-dependent fashion following concentration of the parasite extract. Apoptosis was also confirmed by DNA ladder formation. Characteristic DNA ladders, consisting of multimers of approximately 180 to 200 bp, were produced by tumor cells exposed to Acanthamoeba cell extracts. The morphology of tumor cell lysis was examined by light and scanning electron microscopy. Tumor cells exposed to parasite extract displayed morphological features characteristic of apoptosis including cell shrinkage, cell membrane blebbing, formation of apoptotic bodies, and nuclear condensation. By contrast, similar effects were not found in tumor cells exposed to extract similarly prepared from normal mammalian cells (i.e., human keratocytes). The results suggest that at least one species of pathogenic free-living amoeba is able to lyse tumor cells by a process that culminates in apoptosis. PMID:8132336

  9. Coupling Immunodeficiency factors to a normal cell system growing conjointly with tumor cells

    NASA Astrophysics Data System (ADS)

    Shojania Feizabadi, Mitra; Witten, Tarynn M.

    2014-03-01

    In this work, we modify Witten's conjoint normal-tumor cell model in order to incorporate the presence of a simple immune system. We first examine the behavior of normal and tumor cells when tumor cells interact with surrounding normal cells. We then extend our model and add the effects of a simple immune system, immune-suppression factors and immune-chemotherapeutics agents. The evolution of the system variables is investigated via computer simulation. We show that the evolution of normal and tumor cells population is significantly affected by the choice of drug or immunodeficiency.

  10. Internalization of Vectored Liposomes in a Culture of Poorly Differentiated Tumor Cells.

    PubMed

    Mel'nikov, P A; Baklaushev, V P; Gabashvili, A N; Nukolova, N V; Levinsky, A B; Chehonin, V P

    2016-08-01

    Internalization of liposomal nanocontainers conjugated with monoclonal antibodies to VEGF, VEGFR2 (KDR), and proteins overproduced in the tumor tissue was studied in vitro on cultures of poorly differentiated tumor cells. Comparative analysis of accumulation of vectored liposomes in the tumor cells was performed by evaluating co-localization of labeled containers and cell organelles by laser scanning confocal microscopy. We observed nearly 2 times more active penetration and accumulation of liposomes vectored with antibodies in the tumor cells in comparison with non-vectored liposomes. Selective clathrin-dependent penetration of vectored liposomes into tumor cells was demonstrated by using pharmacological agents inhibiting endocytosis. PMID:27590766

  11. Epidermal growth factor induces WISP-2/CCN5 expression in estrogen receptor-alpha-positive breast tumor cells through multiple molecular cross-talks.

    PubMed

    Banerjee, Snigdha; Sengupta, Krishanu; Saxena, Neela K; Dhar, Kakali; Banerjee, Sushanta K

    2005-03-01

    Epidermal growth factor (EGF) is a mitogen for estrogen receptor (ER)-positive breast tumor cells, and it has been proven that EGF occasionally mimicked estrogen action and cross-talks with ER-alpha to exert its activity. Therefore, the present study was undertaken to explore whether EGF is able to modulate the expression of Wnt-1-induced signaling protein-2/connective tissue growth factor/cysteine-rich 61/nephroblastoma overexpressed 5 (WISP-2/CCN5), an estrogen-responsive gene, in normal and transformed cell lines of the human breast and, if so, whether this induction is critical for EGF mitogenesis and what downstream signaling pathways are associated with this event. Here, we show that EGF-induced WISP-2 expression in ER- and EGF receptor-positive noninvasive MCF-7 breast tumor cells was dose and time dependent and that expression was modulated at transcription level. A synergism was seen in combination with estrogen. Moreover, small interfering RNA-mediated inhibition of WISP-2/CCN5 activity in MCF-7 cells resulted in abrogation of proliferation by EGF. The multiple molecular cross-talks, including the interactions between phosphatidylinositol 3-kinase/Akt and mitogen-activated protein kinase signaling pathways and two diverse receptors (i.e., ER-alpha and EGFR), were essential in the event of EGF-induced WISP-2/CCN5 up-regulation in MCF-7 cells. Moreover, EGF action on WISP-2/CCN5 is restricted to ER- and EGFR-positive noninvasive breast tumor cells, and this effect of EGF cannot be instigated in ER-alpha-negative and EGFR-positive normal or invasive breast tumor cells by introducing ER-alpha. Finally, regulation of phosphorylation of ER-alpha and EGFR may play critical roles in EGF-induced transcriptional activation of WISP-2 gene in breast tumor cells.

  12. Correlations of polyploidy and apomixis with elevation and associated environmental gradients in an alpine plant

    PubMed Central

    Schinkel, Christoph C. F.; Kirchheimer, Bernhard; Dellinger, Agnes S.; Klatt, Simone; Winkler, Manuela; Dullinger, Stefan; Hörandl, Elvira

    2016-01-01

    Apomictic plants expand their geographical distributions more to higher elevations compared to their sexual progenitors. It was so far unclear whether this tendency is related to mode of reproduction itself or represents a side effect of polyploidy. Apomixis is advantageous for range expansions as no mating partners and pollinators are needed (Baker’s rule). Polyploidy is thought to infer fitness advantages and a higher vigour that would enable plants to adjust better to more extreme climatic conditions. However, little is known about actual performance of plants at higher elevations. We analyzed 81 populations of Ranunculus kuepferi from the whole distribution area in the European Alps to quantify apomictic versus sexual seed formation via flow cytometric seed screening. Seed set and vegetative growth were measured as fitness parameters. All parameters were correlated to geographical distribution, elevation, temperature and precipitation. Flow cytometric seed screening revealed predominantly obligate sexuality (88.9 %) and facultative apomixis in diploid populations, while tetraploid populations are predominantly facultative (65.4 %) to obligate apomictic. Apomictic seed formation correlated significantly to higher elevations, which explains also the observed niche shift to lower temperatures. However, within the tetraploid range, there is no apparent correlation of degree of facultative apomixis to geographical distance. Apomixis appeared in diploids three times independently in separated, otherwise sexual populations in the southwestern refugial areas of the Alps. Diploid apomixis was not successful in range expansions, and obligate sexual polyploids were not observed. Polyploidy may relate to cold tolerance as an adaptation to conditions at high elevations, where diploid sexuals have no fitness advantage. Instead, facultative apomixis may have aided colonization of higher elevations and range expansions in the Alps without mate and pollinator limitation

  13. Genome size variation and incidence of polyploidy in Scrophulariaceae sensu lato from the Iberian Peninsula

    PubMed Central

    Castro, Mariana; Castro, Sílvia; Loureiro, João

    2012-01-01

    Background and aims In the last decade, genomic studies using DNA markers have strongly influenced the current phylogeny of angiosperms. Genome size and ploidy level have contributed to this discussion, being considered important characters in biosystematics, ecology and population biology. Despite the recent increase in studies related to genome size evolution and polyploidy incidence, only a few are available for Scrophulariaceae. In this context, we assessed the value of genome size, mostly as a taxonomic marker, and the role of polyploidy as a process of genesis and maintenance of plant diversity in Scrophulariaceae sensu lato in the Iberian Peninsula. Methodology Large-scale analyses of genome size and ploidy-level variation across the Iberian Peninsula were performed using flow cytometry. One hundred and sixty-two populations of 59 distinct taxa were analysed. A bibliographic review on chromosome counts was also performed. Principal results From the 59 sampled taxa, 51 represent first estimates of genome size. The majority of the Scrophulariaceae species presented very small to small genome sizes (2C ≤ 7.0 pg). Furthermore, in most of the analysed genera it was possible to use this character to separate several taxa, independently if these genera were homoploid or heteroploid. Also, some genome-related phenomena were detected, such as intraspecific variation of genome size in some genera and the possible occurrence of dysploidy in Verbascum spp. With respect to polyploidy, despite a few new DNA ploidy levels having been detected in Veronica, no multiple cytotypes have been found in any taxa. Conclusions This work contributed with important basic scientific knowledge on genome size and polyploid incidence in the Scrophulariaceae, providing important background information for subsequent studies, with several perspectives for future studies being opened. PMID:23240073

  14. Water permeation drives tumor cell migration in confined microenvironments.

    PubMed

    Stroka, Kimberly M; Jiang, Hongyuan; Chen, Shih-Hsun; Tong, Ziqiu; Wirtz, Denis; Sun, Sean X; Konstantopoulos, Konstantinos

    2014-04-24

    Cell migration is a critical process for diverse (patho)physiological phenomena. Intriguingly, cell migration through physically confined spaces can persist even when typical hallmarks of 2D planar migration, such as actin polymerization and myosin II-mediated contractility, are inhibited. Here, we present an integrated experimental and theoretical approach ("Osmotic Engine Model") and demonstrate that directed water permeation is a major mechanism of cell migration in confined microenvironments. Using microfluidic and imaging techniques along with mathematical modeling, we show that tumor cells confined in a narrow channel establish a polarized distribution of Na+/H+ pumps and aquaporins in the cell membrane, which creates a net inflow of water and ions at the cell leading edge and a net outflow of water and ions at the trailing edge, leading to net cell displacement. Collectively, this study presents an alternate mechanism of cell migration in confinement that depends on cell-volume regulation via water permeation. PMID:24726433

  15. Isolation and retrieval of circulating tumor cells using centrifugal forces

    PubMed Central

    Hou, Han Wei; Warkiani, Majid Ebrahimi; Khoo, Bee Luan; Li, Zi Rui; Soo, Ross A.; Tan, Daniel Shao-Weng; Lim, Wan-Teck; Han, Jongyoon; Bhagat, Ali Asgar S.; Lim, Chwee Teck

    2013-01-01

    Presence and frequency of rare circulating tumor cells (CTCs) in bloodstreams of cancer patients are pivotal to early cancer detection and treatment monitoring. Here, we use a spiral microchannel with inherent centrifugal forces for continuous, size-based separation of CTCs from blood (Dean Flow Fractionation (DFF)) which facilitates easy coupling with conventional downstream biological assays. Device performance was optimized using cancer cell lines (> 85% recovery), followed by clinical validation with positive CTCs enumeration in all samples from patients with metastatic lung cancer (n = 20; 5–88 CTCs per mL). The presence of CD133+ cells, a phenotypic marker characteristic of stem-like behavior in lung cancer cells was also identified in the isolated subpopulation of CTCs. The spiral biochip identifies and addresses key challenges of the next generation CTCs isolation assay including antibody independent isolation, high sensitivity and throughput (3 mL/hr); and single-step retrieval of viable CTCs. PMID:23405273

  16. Hyperthermic effects of gold nanorods on tumor cells

    PubMed Central

    Huff, Terry B.; Tong, Ling; Zhao, Yan; Hansen, Matthew N.; Cheng, Ji-Xin; Wei, Alexander

    2008-01-01

    Summary Plasmon-resonant gold nanorods, which have large absorption cross sections at near-infrared (NIR) frequencies, are excellent candidates as multifunctional agents for image-guided therapies based on localized hyperthermia. The controlled modification of the nanorods' surface chemistry is of critical importance, as issues of cell-specific targeting and nonspecific uptake must be addressed prior to clinical evaluation. Nanorods coated with CTAB (a cationic surfactant used in nanorod synthesis) are internalized within hours into KB cells by a nonspecific uptake pathway, whereas the careful removal of CTAB from nanorods functionalized with folate results in their accumulation on the cell surface over the same time interval. In either case, the nanorods render the tumor cells highly susceptible to photothermal damage when irradiated at the nanorods' longitudinal plasmon resonance, generating extensive blebbing of the cell membrane at laser fluences as low as 44 W/cm2. PMID:17716198

  17. Water Permeation Drives Tumor Cell Migration in Confined Microenvironments

    PubMed Central

    Stroka, Kimberly M.; Jiang, Hongyuan; Chen, Shih-Hsun; Tong, Ziqiu; Wirtz, Denis; Sun, Sean X.; Konstantopoulos, Konstantinos

    2014-01-01

    SUMMARY Cell migration is a critical process for diverse (patho) physiological phenomena. Intriguingly, cell migration through physically confined spaces can persist even when typical hallmarks of 2D planar migration, such as actin polymerization and myosin II-mediated contractility, are inhibited. Here, we present an integrated experimental and theoretical approach (“Osmotic Engine Model”) and demonstrate that directed water permeation is a major mechanism of cell migration in confined microenvironments. Using microfluidic and imaging techniques along with mathematical modeling, we show that tumor cells confined in a narrow channel establish a polarized distribution of Na+/H+ pumps and aquaporins in the cell membrane, which creates a net inflow of water and ions at the cell leading edge and a net outflow of water and ions at the trailing edge, leading to net cell displacement. Collectively, this study presents an alternate mechanism of cell migration in confinement that depends on cell-volume regulation via water permeation. PMID:24726433

  18. Nanostructured substrates for isolation of circulating tumor cells

    PubMed Central

    Wang, Lixue; Asghar, Waseem; Demirci, Utkan; Wan, Yuan

    2014-01-01

    Summary Circulating tumor cells (CTCs) originate from the primary tumor mass and enter into the peripheral bloodstream. CTCs hold the key to understanding the biology of metastasis and also play a vital role in cancer diagnosis, prognosis, disease monitoring, and personalized therapy. However, CTCs are rare in blood and hard to isolate. Additionally, the viability of CTCs can easily be compromised under high shear stress while releasing them from a surface. The heterogeneity of CTCs in biomarker expression makes their isolation quite challenging; the isolation efficiency and specificity of current approaches need to be improved. Nanostructured substrates have emerged as a promising biosensing platform since they provide better isolation sensitivity at the cost of specificity for CTC isolation. This review discusses major challenges faced by CTC isolation techniques and focuses on nanostructured substrates as a platform for CTC isolation. PMID:24944563

  19. Significance of Circulating Tumor Cells in Soft Tissue Sarcoma

    PubMed Central

    Nicolazzo, Chiara; Gradilone, Angela

    2015-01-01

    Circulating tumor cells can be detected from the peripheral blood of cancer patients. Their prognostic value has been established in the last 10 years for metastatic colorectal, breast, and prostate cancer. On the contrary their presence in patients affected by sarcomas has been poorly investigated. The discovery of EpCAM mRNA expression in different sarcoma cell lines and in a small cohort of metastatic sarcoma patients supports further investigations on these rare tumors to deepen the importance of CTC isolation. Although it is not clear whether EpCAM expression might be originally present on tumor sarcoma cells or acquired during the mesenchymal-epithelial transition, the discovery of EpCAM on circulating sarcoma cells opens a new scenario in CTC detection in patients affected by a rare mesenchymal tumor. PMID:26167450

  20. Akt-dependent metabolic reprogramming regulates tumor cell histone acetylation

    PubMed Central

    Snyder, Nathaniel W.; Wei, Shuanzeng; Venneti, Sriram; Worth, Andrew J.; Yuan, Zuo-Fei; Lim, Hee-Woong; Liu, Shichong; Jackson, Ellen; Aiello, Nicole M.; Haas, Naomi B.; Rebbeck, Timothy R.; Judkins, Alexander; Won, Kyoung-Jae; Chodosh, Lewis A.; Garcia, Benjamin A.; Stanger, Ben Z.; Feldman, Michael D.; Blair, Ian A.; Wellen, Kathryn E.

    2014-01-01

    SUMMARY Histone acetylation plays important roles in gene regulation, DNA replication, and the response to DNA damage, and it is frequently deregulated in tumors. We postulated that tumor cell histone acetylation levels are determined in part by changes in acetyl-CoA availability mediated by oncogenic metabolic reprogramming. Here, we demonstrate that acetyl-CoA is dynamically regulated by glucose availability in cancer cells and that the ratio of acetyl-CoA: coenzyme A within the nucleus modulates global histone acetylation levels. In vivo, expression of oncogenic Kras or Akt stimulates histone acetylation changes that precede tumor development. Furthermore, we show that Akt's effects on histone acetylation are mediated through the metabolic enzyme ATP-citrate lyase (ACLY), and that pAkt(Ser473) levels correlate significantly with histone acetylation marks in human gliomas and prostate tumors. The data implicate acetyl-CoA metabolism as a key determinant of histone acetylation levels in cancer cells. PMID:24998913

  1. What's new on circulating tumor cells? A meeting report

    PubMed Central

    2010-01-01

    Circulating tumor cells (CTCs) provide unique information for the management of cancer patients. The 7th International Symposium on Minimal Residual Cancer has focused on state of the art research, including exciting advances in understanding the biology of metastasis, CTCs and tumor dormancy. Particular emphasis was placed on the relationship of CTCs to cancer stem cells (CSCs) and the relevance of most recent findings for the development of new targeted therapies. CTCs were evaluated as promising tumor biomarkers and the design and results of the first clinical trials to determine their clinical utility were discussed together with state of the art technology platforms for CTC imaging, detection, quantification and molecular characterization. A liquid biopsy approach that can be used for prognostic and predictive purposes was proposed for the analysis of CTCs. PMID:20727231

  2. Nexavar/Stivarga and viagra interact to kill tumor cells.

    PubMed

    Tavallai, Mehrad; Hamed, Hossein A; Roberts, Jane L; Cruickshanks, Nichola; Chuckalovcak, John; Poklepovic, Andrew; Booth, Laurence; Dent, Paul

    2015-09-01

    We determined whether the multi-kinase inhibitor sorafenib or its derivative regorafenib interacted with phosphodiesterase 5 (PDE5) inhibitors such as Viagra (sildenafil) to kill tumor cells. PDE5 and PDGFRα/β were over-expressed in liver tumors compared to normal liver tissue. In multiple cell types in vitro sorafenib/regorafenib and PDE5 inhibitors interacted in a greater than additive fashion to cause tumor cell death, regardless of whether cells were grown in 10 or 100% human serum. Knock down of PDE5 or of PDGFRα/β recapitulated the effects of the individual drugs. The drug combination increased ROS/RNS levels that were causal in cell killing. Inhibition of CD95/FADD/caspase 8 signaling suppressed drug combination toxicity. Knock down of ULK-1, Beclin1, or ATG5 suppressed drug combination lethality. The drug combination inactivated ERK, AKT, p70 S6K, and mTOR and activated JNK. The drug combination also reduced mTOR protein expression. Activation of ERK or AKT was modestly protective whereas re-expression of an activated mTOR protein or inhibition of JNK signaling almost abolished drug combination toxicity. Sildenafil and sorafenib/regorafenib interacted in vivo to suppress xenograft tumor growth using liver and colon cancer cells. From multiplex assays on tumor tissue and plasma, we discovered that increased FGF levels and ERBB1 and AKT phosphorylation were biomarkers that were directly associated with lower levels of cell killing by 'rafenib + sildenafil. Our data are now being translated into the clinic for further determination as to whether this drug combination is a useful anti-tumor therapy for solid tumor patients. PMID:25704960

  3. Murine macrophage heparanase: inhibition and comparison with metastatic tumor cells

    SciTech Connect

    Savion, N.; Disatnik, M.H.; Nevo, Z.

    1987-01-01

    Circulating macrophages and metastatic tumor cells can penetrate the vascular endothelium and migrate from the circulatory system to extravascular compartments. Both activated murine macrophages and different metastatic tumor cells attach, invade, and penetrate confluent vascular endothelial cell monolayer in vitro, by degrading heparan sulfate proteoglycans in the subendothelial extracellular matrix. The sensitivity of the enzymes from the various sources degrading the heparan sulfate proteoglycan was challenged and compared by a series of inhibitors. Activated macrophages demonstrate a heparanase with an endoglycosidase activity that cleaves from the (/sup 35/S)O/sub 4//sup -/-labeled heparan sulfate proteoglycans of the extracellular matrix 10 kDa glycosaminoglycan fragments. The degradation of (/sup 35/S)O/sub 4//sup -/-labeled extracellular matrix proteoglycans by the macrophages' heparanase is significantly inhibited in the presence of heparan sulfate (10..mu..g/ml), arteparon (10..mu..g/ml), and heparin at a concentration of 3 ..mu..g/ml. Degradation of this heparan sulfate proteoglycan is a two-step sequential process involving protease activity followed by heparanase activity. B16-BL6 metastatic melanoma cell heparanase, which is also a cell-associated enzyme, was inhibited by heparin to the same extent as the macrophage haparanase. On the other hand, heparanase of the highly metastatic variant (ESb) of a methylcholanthrene-induced T lymphoma, which is an extracellular enzyme released by the cells to the incubation medium, was more sensitive to heparin and arteparon than the macrophages' heparanase. These results may indicate the potential use of heparin or other glycosaminoglycans as specific and differential inhibitors for the formation in certain cases of blood-borne tumor metastasis.

  4. Apoptosis by Direct Current Treatment in Tumor Cells and Tissues

    NASA Astrophysics Data System (ADS)

    Kim, Hongbae; Sim, Sungbo; Ahn, Saeyoung

    2003-10-01

    Electric field induces cell fusion, electroporation on biological cells, including apoptosis. Apoptosis is expressed in a series of natural enzymatic reactions for the natural elimination of unhealthy, genetically damaged, or otherwise aberrant cells that are not needed or not advantageous to the well-being of the organism. Its markers involve cell shrinkage, activation of intracellular caspase proteases, externalization of phosphatidylserine at the plasma membrane, and fragmentation of DNA. Direct electric fields using direct current have been exploited recently to investigate its effects on tumor cells and tissues, but the mechanism of direct electric fields has not been exhibited clearly other than by electroosmosis or pH changes. Direct electric field induces apoptosis in tumor cells cultured and tumor tissues as indicated by cell shrinkage, DNA fragmentation and tumor suppression. In our experiment that direct electric field was applied to tumor tissues via two needle electrodes inserted into tumor tissue 5mm at distance in parallel, pH changes resulted from electrochemical reaction, exhibiting about pH 9.0, 1.83, 2.0 in the vicinity of cathodic and anodic electrode, and at their mid-point, respectively. DNA fragmentation of tumor tissues destructed by direct electric field was analyzed by Tunel assay by ApopTag technology. As a result of this analysis, it showed that apoptosis in tumor tissue destructed was increased up to 59.1normal(control) tissues, showing 41.1, 31.1cathodic tissues. In vitro cell survival was exhibited that it was decreased with enhancing electric current intensity in the same condition of electrical charge 5C having different time applied. We will show results of apoptosis analyzed by flow cytometry in vitro.

  5. Nexavar/Stivarga and Viagra Interact to Kill Tumor Cells

    PubMed Central

    Tavallai, Mehrad; Hamed, Hossein A.; Roberts, Jane L.; Cruickshanks, Nichola; Chuckalovcak, John; Poklepovic, Andrew; Booth, Laurence

    2015-01-01

    We determined whether the multi‐kinase inhibitor sorafenib or its derivative regorafenib interacted with phosphodiesterase 5 (PDE5) inhibitors such as Viagra (sildenafil) to kill tumor cells. PDE5 and PDGFRα/β were over‐expressed in liver tumors compared to normal liver tissue. In multiple cell types in vitro sorafenib/regorafenib and PDE5 inhibitors interacted in a greater than additive fashion to cause tumor cell death, regardless of whether cells were grown in 10 or 100% human serum. Knock down of PDE5 or of PDGFRα/β recapitulated the effects of the individual drugs. The drug combination increased ROS/RNS levels that were causal in cell killing. Inhibition of CD95/FADD/caspase 8 signaling suppressed drug combination toxicity. Knock down of ULK‐1, Beclin1, or ATG5 suppressed drug combination lethality. The drug combination inactivated ERK, AKT, p70 S6K, and mTOR and activated JNK. The drug combination also reduced mTOR protein expression. Activation of ERK or AKT was modestly protective whereas re‐expression of an activated mTOR protein or inhibition of JNK signaling almost abolished drug combination toxicity. Sildenafil and sorafenib/regorafenib interacted in vivo to suppress xenograft tumor growth using liver and colon cancer cells. From multiplex assays on tumor tissue and plasma, we discovered that increased FGF levels and ERBB1 and AKT phosphorylation were biomarkers that were directly associated with lower levels of cell killing by ‘rafenib + sildenafil. Our data are now being translated into the clinic for further determination as to whether this drug combination is a useful anti‐tumor therapy for solid tumor patients. J. Cell. Physiol. 230: 2281–2298, 2015. © 2015 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc. PMID:25704960

  6. Characterization of circulating tumor cells by fluorescence in situ hybridization.

    PubMed

    Swennenhuis, Joost F; Tibbe, Arjan G J; Levink, Rianne; Sipkema, Ronald C J; Terstappen, Leon W M M

    2009-06-01

    Tumor cells in blood of patients with metastatic carcinomas have been associated with poor survival prospects. Further characterization of these cells may provide further insights into the metastatic process. Circulating Tumor Cells (CTC) were enumerated in 7.5 mL of blood with the CellSearch system. After enumeration of Cytokeratin+, CD45-, nucleated cells, the cells are fixed in the cartridge while maintaining their original position. Cartridges were hybridized with FISH probes against the centromeric regions of chromosome 1, 7, 8, and 17. Next fluorescence images of the FISH probes of the previous identified CTC were acquired. Leukocytes surrounding the CTC were used as internal controls. The number of copies of chromosome 1, 7, 8, and 17 could be determined in 118 CTC containing blood samples from 59 metastatic prostate cancer patients. The samples contained a total of 21,751 CTC (mean 184, median 16, SD 650). Chromosome counts were obtained in 61% of the relocated CTC. On an average, these CTC contained 2.8 copies of chromosome 1, 2.7 copies of chromosome 7, 3.1 copies of chromosome 8, and 2.3 copies of chromosome 17. CTC in which no chromosome count was obtained most likely underwent apoptosis indicated by the expression of M30. In 6/59 patients only diploid CTC were detected these samples, however, only contained 1-5 CTC. Heterogeneity in the chromosomal abnormalities was observed between CTC of different patients as well as among CTC of the same patient. Cytogenetic composition of CTC can be reliably assessed after they have been identified by the CellSearch system. The majority of CTC in hormone refractory prostate cancer are aneuploid confirming that they indeed are cancer cells. An extensive heterogeneity in the copy number of each of the chromosomes was observed.

  7. Filter Characteristics Influencing Circulating Tumor Cell Enrichment from Whole Blood

    PubMed Central

    Beck, Markus; Terstappen, Leon W. M. M.

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45−DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9–19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11–13 µm should be used to challenge the system. PMID:23626725

  8. Filter characteristics influencing circulating tumor cell enrichment from whole blood.

    PubMed

    Coumans, Frank A W; van Dalum, Guus; Beck, Markus; Terstappen, Leon W M M

    2013-01-01

    A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45-DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9-19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11-13 µm should be used to challenge the system.

  9. Expression of stage-specific embryonic antigen-4 (SSEA-4) defines spontaneous loss of epithelial phenotype in human solid tumor cells.

    PubMed

    Sivasubramaniyan, Kavitha; Harichandan, Abhishek; Schilbach, Karin; Mack, Andreas F; Bedke, Jens; Stenzl, Arnulf; Kanz, Lothar; Niederfellner, Gerhard; Bühring, Hans-Jörg

    2015-08-01

    Stage-specific embryonic antigen-4 (SSEA-4) is a glycosphingolipid, which is overexpressed in some cancers and has been linked to disease progression. However, little is known about the functions of SSEA-4 and the characteristics of SSEA-4 expressing tumor cells. Our studies identified SSEA-4 expression on a subpopulation of cells in many solid tumor cell lines but not in leukemic cell lines. Fluorescence-activated cell sorting-sorted SSEA-4(+) prostate cancer cells formed fibroblast-like colonies with limited cell-cell contacts, whereas SSEA-4(-) cells formed cobblestone-like epithelial colonies. Only colonies derived from SSEA-4(+) cells were enriched for pluripotent embryonic stem cell markers. Moreover, major epithelial cell-associated markers Claudin-7, E-cadherin, ESRP1 and GRHL2 were down-regulated in the SSEA-4(+) fraction of DU145 and HCT-116 cells. Similar to cell lines, SSEA-4(+) primary prostate tumor cells also showed down-regulation of epithelial cell-associated markers. In addition, they showed up-regulation of epithelial-to-mesenchymal transition as well as mesenchymal markers. Furthermore, SSEA-4(+) cells escape from adhesive colonies spontaneously and form invadopodia-like migratory structures, in which SSEA-4, cortactin as well as active pPI3K, pAkt and pSrc are enriched and colocalized. Finally, SSEA-4(+) cells displayed strong tumorigenic ability and stable knockdown of SSEA-4 synthesis resulted in decreased cellular adhesion to different extracellular matrices. In conclusion, we introduce SSEA-4 as a novel marker to identify heterogeneous, invasive subpopulations of tumor cells. Moreover, increased cell-surface SSEA-4 expression is associated with the loss of cell-cell interactions and the gain of a migratory phenotype, suggesting an important role of SSEA-4 in cancer invasion by influencing cellular adhesion to the extracellular matrix.

  10. Mutational analysis of single circulating tumor cells by next generation sequencing in metastatic breast cancer

    PubMed Central

    Galardi, Francesca; Pestrin, Marta; Gabellini, Stefano; Simi, Lisa; Mancini, Irene; Vannucchi, Alessandro Maria; Pazzagli, Mario; Di Leo, Angelo; Pinzani, Pamela

    2016-01-01

    Circulating Tumor Cells (CTCs) represent a “liquid biopsy” of the tumor potentially allowing real-time monitoring of cancer biology and therapies in individual patients. The purpose of the study was to explore the applicability of a protocol for the molecular characterization of single CTCs by Next Generation Sequencing (NGS) in order to investigate cell heterogeneity and provide a tool for a personalized medicine approach. CTCs were enriched and enumerated by CellSearch in blood from four metastatic breast cancer patients and singularly isolated by DEPArray. Upon whole genome amplification 3–5 single CTCs per patient were analyzed by NGS for 50 cancer-related genes. We found 51 sequence variants in 25 genes. We observed inter- and intra-patient heterogeneity in the mutational status of CTCs. The highest number of somatic deleterious mutations was found in the gene TP53, whose mutation is associated with adverse prognosis in breast cancer. The discordance between the mutational status of the primary tumor and CTCs observed in 3 patients suggests that, in advanced stages of cancer, CTC characteristics are more closely linked to the dynamic modifications of the disease status. In one patient the mutational profiles of CTCs before and during treatment shared only few sequence variants. This study supports the applicability of a non-invasive approach based on the liquid biopsy in metastatic breast cancer patients which, in perspective, should allow investigating the clonal evolution of the tumor for the development of new therapeutic strategies in precision medicine. PMID:27034166

  11. Receptor tyrosine kinase expression of circulating tumor cells in small cell lung cancer

    PubMed Central

    Hamilton, Gerhard; Rath, Barbara; Klameth, Lukas; Hochmair, Maximilian

    2015-01-01

    Small cell lung cancer (SCLC) has a poor prognosis and is found disseminated at first presentation in the majority of cases. The cell biological mechanisms underlying metastasis and drug resistance are not clear. SCLC is characterized by high numbers of circulating tumor cells (CTCs) and we were able to expand several CTC lines ex vivo and to relate chitinase-3-like-1/YKL-40 (CHI3L1) as marker. Availability of expanded SCLC CTC cells allowed for a screening of receptor tyrosine kinases (RTKs) expressed. The metastatic CHI3L1-negative SCLC cell line SCLC26A, established from a pleural effusion was used for comparison. The CTC cell line BHGc10 was found to exhibit increased expression of RYK, AXL, Tie-1, Dtk, ROR1/2, several ephrins (Eph) and FGF/EGF receptors compared to SCLC26A. All of these RTKs have been associated with cell motility, invasion and poor prognosis in diverse cancer entities without knowledge of their association with CTCs. The identification of RYK, AXL and ROR1/2 as pseudokinases, lacking activity, seems to be related to the observed failure of RTK inhibitors in SCLC. These kinases are involved in the noncanonical WNT pathway and their expression in SCLC CTCs represents a cancer stem cell-like phenotype. PMID:26328272

  12. A fully continuous individual-based model of tumor cell evolution.

    PubMed

    Gómez-Mourelo, Pablo; Sánchez, Eva; Casasús, Luis; Webb, Glenn F

    2008-11-01

    The aim of this work is to develop and study a fully continuous individual-based model (IBM) for cancer tumor invasion into a spatial environment of surrounding tissue. The IBM improves previous spatially discrete models, because it is continuous in all variables (including spatial variables), and thus not constrained to lattice frameworks. The IBM includes four types of individual elements: tumor cells, extracellular macromolecules (MM), a matrix degradative enzyme (MDE), and oxygen. The algorithm underlying the IBM is based on the dynamic interaction of these four elements in the spatial environment, with special consideration of mutation phenotypes. A set of stochastic differential equations is formulated to describe the evolution of the IBM in an equivalent way. The IBM is scaled up to a system of partial differential equations (PDE) representing the limiting behavior of the IBM as the number of cells and molecules approaches infinity. Both models (IBM and PDE) are numerically simulated with two kinds of initial conditions: homogeneous MM distribution and heterogeneous MM distribution. With both kinds of initial MM distributions spatial fingering patterns appear in the tumor growth. The output of both simulations is quite similar.

  13. Do Circulating Tumor Cells, Exosomes, and Circulating Tumor Nucleic Acids Have Clinical Utility?

    PubMed Central

    Gold, Bert; Cankovic, Milena; Furtado, Larissa V.; Meier, Frederick; Gocke, Christopher D.

    2016-01-01

    Diagnosing and screening for tumors through noninvasive means represent an important paradigm shift in precision medicine. In contrast to tissue biopsy, detection of circulating tumor cells (CTCs) and circulating tumor nucleic acids provides a minimally invasive method for predictive and prognostic marker detection. This allows early and serial assessment of metastatic disease, including follow-up during remission, characterization of treatment effects, and clonal evolution. Isolation and characterization of CTCs and circulating tumor DNA (ctDNA) are likely to improve cancer diagnosis, treatment, and minimal residual disease monitoring. However, more trials are required to validate the clinical utility of precise molecular markers for a variety of tumor types. This review focuses on the clinical utility of CTCs and ctDNA testing in patients with solid tumors, including somatic and epigenetic alterations that can be detected. A comparison of methods used to isolate and detect CTCs and some of the intricacies of the characterization of the ctDNA are also provided. PMID:25908243

  14. Using circulating tumor cells to inform on prostate cancer biology and clinical utility

    PubMed Central

    Li, Jing; Gregory, Simon G.; Garcia-Blanco, Mariano A.; Armstrong, Andrew J.

    2016-01-01

    Substantial advances in the molecular biology of prostate cancer have led to the approval of multiple new systemic agents to treat men with metastatic castration-resistant prostate cancer (mCRPC). These treatments encompass androgen receptor directed therapies, immunotherapies, bone targeting radiopharmaceuticals and cytotoxic chemotherapies. There is, however, great heterogeneity in the degree of patient benefit with these agents, thus fueling the need to develop predictive biomarkers that are able to rationally guide therapy. Circulating tumor cells (CTCs) have the potential to provide an assessment of tumor-specific biomarkers through a non-invasive, repeatable “liquid biopsy” of a patient’s cancer at a given point in time. CTCs have been extensively studied in men with mCRPC, where CTC enumeration using the Cellsearch® method has been validated and FDA approved to be used in conjunction with other clinical parameters as a prognostic biomarker in metastatic prostate cancer. In addition to enumeration, more sophisticated molecular profiling of CTCs is now feasible and may provide more clinical utility as it may reflect tumor evolution within an individual particularly under the pressure of systemic therapies. Here, we review technologies used to detect and characterize CTCs, and the potential biological and clinical utility of CTC molecular profiling in men with metastatic prostate cancer. PMID:26079252

  15. Liquid biopsy in patients with pancreatic cancer: Circulating tumor cells and cell-free nucleic acids

    PubMed Central

    Imamura, Taisuke; Komatsu, Shuhei; Ichikawa, Daisuke; Kawaguchi, Tsutomu; Miyamae, Mahito; Okajima, Wataru; Ohashi, Takuma; Arita, Tomohiro; Konishi, Hirotaka; Shiozaki, Atsushi; Morimura, Ryo; Ikoma, Hisashi; Okamoto, Kazuma; Otsuji, Eigo

    2016-01-01

    Despite recent advances in surgical techniques and perioperative management, the prognosis of pancreatic cancer (PCa) remains extremely poor. To provide optimal treatment for each patient with Pca, superior biomarkers are urgently needed in all phases of management from early detection to staging, treatment monitoring, and prognosis. In the blood of patients with cancer, circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs), such as DNA, mRNA, and noncoding RNA have been recognized. In the recent years, their presence in the blood has encouraged researchers to investigate their potential use as novel blood biomarkers, and numerous studies have demonstrated their potential clinical utility as a biomarker for certain types of cancer. This concept, called “liquid biopsy” has been focused on as a less invasive, alternative approach to cancer tissue biopsy for obtaining genetic and epigenetic aberrations that contribute to oncogenesis and cancer progression. In this article, we review the available literature on CTCs and cfNAs in patients with cancer, particularly focusing on PCa, and discuss future perspectives in this field. PMID:27433079

  16. Circulating Tumor Cells: A Review of Present Methods and the Need to Identify Heterogeneous Phenotypes

    PubMed Central

    Millner, Lori M.; Linder, Mark W.; Valdes, Roland

    2016-01-01

    The measurement and characterization of circulating tumor cells (CTCs) hold promise for advancing personalized therapeutics. CTCs are the precursor to metastatic cancer and thus have the potential to radically alter patient treatment and outcome. Currently, clinical information provided by the enumeration of CTCs is limited to predicting clinical outcome. Other areas of interest in advancing the practice of pathology include: using CTCs for early detection of potential metastasis, determining and monitoring the efficacy of individualized treatment regimens, and predicting site-specific metastasis. Important hurdles to overcome in obtaining this type of clinical information involve present limitations in defining, detecting, and isolating CTCs. Currently, CTCs are detected using epithelial markers. The definition of what distinguishes a CTC should be expanded to include CTCs with heterogeneous phenotypes, and markers should be identified to enable a more comprehensive capture. Additionally, most methods available for detecting CTCs do not capture functionally viable CTCs. Retaining functional viability would provide a significant advantage in characterizing CTC-subtypes that may predict the site of metastatic invasion and thus assist in selecting effective treatment regimens. In this review we describe areas of clinical interest followed by a summary of current circulating cell-separation technologies and present limitations. Lastly, we provide insight into what is required to overcome these limitations as they relate to applications in advancing the practice of pathology and laboratory medicine. PMID:23884225

  17. B7-1/CD80-transduced tumor cells elicit better systemic immunity than wild-type tumor cells admixed with Corynebacterium parvum.

    PubMed

    Chen, L; McGowan, P; Ashe, S; Johnston, J V; Hellström, I; Hellström, K E

    1994-10-15

    Tumor cells genetically modified by transduction of B7 (B7-1/CD80), a natural ligand for the T-cell costimulatory molecules CD28 and CTLA-4, can elicit potent tumor immunity, and they can be effective for treatment of established cancers in animal models. In this study, three tumor lines, the EL4 lymphoma, the P815 mastocytoma, and the MCA102 sarcoma were transduced with recombinant retrovirus containing the murine B7 gene, and their potency to induce systemic immunity protective against challenge with wild-type tumor was compared to that of the same tumor cells admixed with the commonly used adjuvant Corynebacterium parvum. While admixture of tumor cells with C. parvum resulted in complete regression of tumors in syngeneic mice, it did not induce protective immunity against a subsequent challenge of wild-type cells from any of the 3 tumors tested. In contrast, B7-transduced EL4 and P815 tumors regressed locally and induced a potent systemic immunity to wild-type tumors and a higher level of cytotoxic T-cell activity than did tumor cells admixed with C. parvum. No systemic immunity was induced by B7-transduced nonimmunogenic MCA102 sarcoma cells. Our results demonstrate that immunogenic tumor cells transduced with the B7 gene are superior to tumor cells mixed with C. parvum for the induction of systemic tumor immunity. PMID:7522958

  18. Bladder cancers respond to intravesical instillation of HAMLET (human alpha-lactalbumin made lethal to tumor cells).

    PubMed

    Mossberg, Ann-Kristin; Wullt, Björn; Gustafsson, Lotta; Månsson, Wiking; Ljunggren, Eva; Svanborg, Catharina

    2007-09-15

    We studied if bladder cancers respond to HAMLET (human alpha-lactalbumin made lethal to tumor cells) to establish if intravesical HAMLET application might be used to selectively remove cancer cells in vivo. Patients with nonmuscle invasive transitional cell carcinomas were included. Nine patients received 5 daily intravesical instillations of HAMLET (25 mg/ml) during the week before scheduled surgery. HAMLET stimulated a rapid increase in the shedding of tumor cells into the urine, daily, during the 5 days of instillation. The effect was specific for HAMLET, as intravesical instillation of NaCl, PBS or native alpha-lactalbumin did not increase cell shedding. Most of the shed cells were dead and an apoptotic response was detected in 6 of 9 patients, using the TUNEL assay. At surgery, morphological changes in the exophytic tumors were documented by endoscopic photography and a reduction in tumor size or change in tumor character was detected in 8 of 9 patients. TUNEL staining was positive in biopsies from the remaining tumor in 4 patients but adjacent healthy tissue showed no evidence of apoptosis and no toxic response. The results suggest that HAMLET exerts a direct and selective effect on bladder cancer tissue in vivo and that local HAMLET administration might be of value in the future treatment of bladder cancers.

  19. HGFL supports mammary tumorigenesis by enhancing tumor cell intrinsic survival and influencing macrophage and T-cell responses

    PubMed Central

    Benight, Nancy M.; Wagh, Purnima K.; Zinser, Glendon M.; Peace, Belinda E.; Stuart, William D.; Vasiliauskas, Juozas; Pathrose, Peterson; Starnes, Sandra L.; Waltz, Susan E.

    2015-01-01

    The Ron receptor is overexpressed in human breast cancers and is associated with heightened metastasis and poor survival. Ron overexpression in the mammary epithelium of mice is sufficient to induce aggressive mammary tumors with a high degree of metastasis. Despite the well-documented role of Ron in breast cancer, few studies have examined the necessity of the endogenous Ron ligand, hepatocyte growth factor-like protein (HGFL) in mammary tumorigenesis. Herein, mammary tumor growth and metastasis were examined in mice overexpressing Ron in the mammary epithelium with or without HGFL. HGFL ablation decreased oncogenic Ron activation and delayed mammary tumor initiation. HGFL was important for tumor cell proliferation and survival. HGFL loss resulted in increased numbers of macrophages and T-cells within the tumor. T-cell proliferation and cytotoxicity dramatically increased in HGFL deficient mice. Biochemical analysis of HGFL proficient tumors showed increased local HGFL production, with HGFL loss decreasing β-catenin expression and NF-κB activation. Re-expression of HGFL in HGFL deficient tumor cells stimulated cell migration and invasion with coordinate activation of NF-κB and reduced apoptosis. Together, these results demonstrate critical in vivo functions for HGFL in promoting breast tumorigenesis and suggest that targeting HGFL may inhibit tumor growth and reactivate anti-tumor immune responses. PMID:25938541

  20. p53-Dependent activation of a molecular beacon in tumor cells following exposure to doxorubicin chemotherapy.

    PubMed

    Shah, Rishita; El-Deiry, Wafik S

    2004-09-01

    In an effort to begin developing a non-invasive strategy for in-vivo detection of the cellular DNA damage response, we engineered a molecular beacon to detect expression of p21(WAF1/CIP1), a gene whose transcription is directly activated by the p53 tumor suppressor protein. Introduction of a phosphorothioate-modified p21-beacon by transfection in human tumor cells led to a slight background signal that increased in a dose dependent manner between 50 and 400 nM beacon. Strong nuclear signal was observed following treatment of wild-type p53-expressing human H460 lung cancer cells for 8 hours with the chemotherapeutic agent doxorubicin (adriamycin). Similar induction was observed in wild-type p53-expressing HCT116 cells. Interestingly, following doxorubicin exposure, there was activation of the p21-beacon in p21-null HCT116 cells, which was not observed in p53-null HCT116, or mutant p53-expressing DLD1 cells that are either wild-type or p21-null. Increased signal from the phosphorothioate-modified p21-beacon in doxorubicin-treated cells likely resulted from sequence-specific hybridization as well as sequence-independent cleavage that may occur due to p53-dependent activation of endonucleases during apoptosis. We conclude that activation of p53 by chemotherapy leads to a strong signal from a p21-beacon that may be useful in further testing both in vitro and in vivo. Strategies need to be developed to optimize the gene or damage specificity as well as the sensitivity to therapeutic response of this non-invasive imaging approach.

  1. Optical Detection and Virotherapy of Live Metastatic Tumor Cells in Body Fluids with Vaccinia Strains

    PubMed Central

    Minev, Boris R.; Zimmermann, Martina; Aguilar, Richard J.; Zhang, Qian; Sturm, Julia B.; Fend, Falko; Yu, Yong A.; Cappello, Joseph; Lauer, Ulrich M.; Szalay, Aladar A.

    2013-01-01

    Metastatic tumor cells in body fluids are important targets for treatment, and critical surrogate markers for evaluating cancer prognosis and therapeutic response. Here we report, for the first time, that live metastatic tumor cells in blood samples from mice bearing human tumor xenografts and in blood and cerebrospinal fluid samples from patients with cancer were successfully detected using a tumor cell-specific recombinant vaccinia virus (VACV). In contrast to the FDA-approved CellSearch system, VACV detects circulating tumor cells (CTCs) in a cancer biomarker-independent manner, thus, free of any bias related to the use of antibodies, and can be potentially a universal system for detection of live CTCs of any tumor type, not limited to CTCs of epithelial origin. Furthermore, we demonstrate for the first time that VACV was effective in preventing and reducing circulating tumor cells in mice bearing human tumor xenografts. Importantly, a single intra-peritoneal delivery of VACV resulted in a dramatic decline in the number of tumor cells in the ascitic fluid from a patient with gastric cancer. Taken together, these results suggest VACV to be a useful tool for quantitative detection of live tumor cells in liquid biopsies as well as a potentially effective treatment for reducing or eliminating live tumor cells in body fluids of patients with metastatic disease. PMID:24019862

  2. Multimodality Raman and photoacoustic imaging of surface-enhanced-Raman-scattering-targeted tumor cells

    NASA Astrophysics Data System (ADS)

    Shi, Wei; Paproski, Robert J.; Shao, Peng; Forbrich, Alexander; Lewis, John D.; Zemp, Roger J.

    2016-02-01

    A multimodality Raman and photoacoustic imaging system is presented. This system has ultralow background and can detect tumor cells labeled with modified surface-enhanced-Raman-scattering (SERS) nanoparticles in vivo. Photoacoustic imaging provides microvascular context and can potentially be used to guide magnetic trapping of circulating tumor cells for SERS detection in animal models.

  3. Effect of epithermal neutrons on viability of glioblastoma tumor cells in vitro.

    PubMed

    Mostovich, L A; Gubanova, N V; Kutsenko, O S; Aleinik, V I; Kuznetsov, A S; Makarov, A N; Sorokin, I N; Taskaev, S Yu; Nepomnyashchikh, G I; Grigor'eva, E V

    2011-06-01

    We studied in vitro effect of epithermal neutrons in various doses on viability of glioblastoma U87 tumor cells. Increasing the dose from 1.9 to 4.1 Sv promoted cell death. Cytofluorimetric analysis revealed no activation of apoptosis in the irradiated cells, which attested to necrotic death of the tumor cells exposed to epithermal neutron radiation.

  4. HAMLET triggers apoptosis but tumor cell death is independent of caspases, Bcl-2 and p53.

    PubMed

    Hallgren, O; Gustafsson, L; Irjala, H; Selivanova, G; Orrenius, S; Svanborg, C

    2006-02-01

    HAMLET (Human alpha-lactalbumin Made Lethal to Tumor cells) triggers selective tumor cell death in vitro and limits tumor progression in vivo. Dying cells show features of apoptosis but it is not clear if the apoptotic response explains tumor cell death. This study examined the contribution of apoptosis to cell death in response to HAMLET. Apoptotic changes like caspase activation, phosphatidyl serine externalization, chromatin condensation were detected in HAMLET-treated tumor cells, but caspase inhibition or Bcl-2 over-expression did not prolong cell survival and the caspase response was Bcl-2 independent. HAMLET translocates to the nuclei and binds directly to chromatin, but the death response was unrelated to the p53 status of the tumor cells. p53 deletions or gain of function mutations did not influence the HAMLET sensitivity of tumor cells. Chromatin condensation was partly caspase dependent, but apoptosis-like marginalization of chromatin was also observed. The results show that tumor cell death in response to HAMLET is independent of caspases, p53 and Bcl-2 even though HAMLET activates an apoptotic response. The use of other cell death pathways allows HAMLET to successfully circumvent fundamental anti-apoptotic strategies that are present in many tumor cells.

  5. Platelets alter tumor cell attributes to propel metastasis: programming in transit.

    PubMed

    Gay, Laurie J; Felding-Habermann, Brunhilde

    2011-11-15

    Metastasis of epithelial tumors critically depends on acquisition of a disseminating phenotype that allows tumor cells to colonize distant organs. In this issue of Cancer Cell, Labelle et al. demonstrate that an epithelial-mesenchymal-like transition can be induced by interaction between platelets and tumor cells.

  6. A recent polyploidy superimposed on older large-scale duplications in the Arabidopsis genome.

    PubMed

    Blanc, Guillaume; Hokamp, Karsten; Wolfe, Kenneth H

    2003-02-01

    The Arabidopsis genome contains numerous large duplicated chromosomal segments, but the different approaches used in previous analyses led to different interpretations regarding the number and timing of ancestral large-scale duplication events. Here, using more appropriate methodology and a more recent version of the genome sequence annotation, we investigate the scale and timing of segmental duplications in Arabidopsis. We used protein sequence similarity searches to detect duplicated blocks in the genome, used the level of synonymous substitution between duplicated genes to estimate the relative ages of the blocks containing them, and analyzed the degree of overlap between adjacent duplicated blocks. We conclude that the Arabidopsis lineage underwent at least two distinct episodes of duplication. One was a polyploidy that occurred much more recently than estimated previously, before the Arabidopsis/Brassica rapa split and probably during the early emergence of the crucifer family (24-40 Mya). An older set of duplicated blocks was formed after the monocot/dicot divergence, and the relatively low level of overlap among these blocks indicates that at least some of them are remnants of a larger duplication such as a polyploidy or aneuploidy.

  7. Effect of induced polyploidy on some biochemical parameters in Cannabis sativa L.

    PubMed

    Bagheri, Mahsa; Mansouri, Hakimeh

    2015-03-01

    This study is aimed at testing the efficiency of colchicine on inducing polyploidy in Cannabis sativa L. and investigation of effects of polyploidy induction on some primary and secondary metabolites. Shoot tips were treated with three different concentrations of colchicine (0, 0.1, 0.2 % w/v) for 24 or 48 h. The biggest proportion of the almost coplanar tetraploids (43.33 %) and mixoploids (13.33 %) was obtained from the 24-h treatment in 0.2 and 0.1 % w/v, respectively. Colchicine with 0.2 % concentration and 48 h duration was more destructive than 24 h. The ploidy levels were screened with flow cytometry. The biochemical analyses showed that reducing sugars, soluble sugars, total protein, and total flavonoids increased significantly in mixoploid plants compared with tetraploid and diploid plants. Tetraploid plants had a higher amount of total proteins, total flavonoids, and starch in comparison with control plants. The results showed that polyploidization could increase the contents of tetrahydrocannabinol in mixoploid plants only, but tetraploid plants had lower amounts of this substance in comparison with diploids. Also, we found such changes in protein concentration in electrophoresis analysis. In overall, our study suggests that tetraploidization could not be useful to produce tetrahydrocannabinol for commercial use, and in this case, mixoploids are more suitable. PMID:25492688

  8. p73 suppresses polyploidy and aneuploidy in the absence of functional p53.

    PubMed

    Talos, Flaminia; Nemajerova, Alice; Flores, Elsa R; Petrenko, Oleksi; Moll, Ute M

    2007-08-17

    Previous studies showed that p53 plays a central role in G1 and DNA damage checkpoints, thus contributing to genomic stability. We show here that p73 also plays a role in genomic integrity but this mechanism is manifest only when p53 is lost. Isolated p73 loss in primary cells does not induce genomic instability. Instead, it results in impaired proliferation and premature senescence due to compensatory activation of p53. Combined loss of p73 and p53 rescues these defects, but at the expense of exacerbated genomic instability. This leads to rapid increase in polyploidy and aneuploidy, markedly exceeding that of p53 loss alone. Constitutive deregulation of cyclin-Cdk activities and excess failure of the G2/M DNA damage checkpoint appear to fuel increased ploidy abnormalities upon p53/p73 loss, while primary mitotic defects do not play a causal role. These data indicate that p73 is essential for suppressing polyploidy and aneuploidy when p53 is inactivated.

  9. Effect of induced polyploidy on some biochemical parameters in Cannabis sativa L.

    PubMed

    Bagheri, Mahsa; Mansouri, Hakimeh

    2015-03-01

    This study is aimed at testing the efficiency of colchicine on inducing polyploidy in Cannabis sativa L. and investigation of effects of polyploidy induction on some primary and secondary metabolites. Shoot tips were treated with three different concentrations of colchicine (0, 0.1, 0.2 % w/v) for 24 or 48 h. The biggest proportion of the almost coplanar tetraploids (43.33 %) and mixoploids (13.33 %) was obtained from the 24-h treatment in 0.2 and 0.1 % w/v, respectively. Colchicine with 0.2 % concentration and 48 h duration was more destructive than 24 h. The ploidy levels were screened with flow cytometry. The biochemical analyses showed that reducing sugars, soluble sugars, total protein, and total flavonoids increased significantly in mixoploid plants compared with tetraploid and diploid plants. Tetraploid plants had a higher amount of total proteins, total flavonoids, and starch in comparison with control plants. The results showed that polyploidization could increase the contents of tetrahydrocannabinol in mixoploid plants only, but tetraploid plants had lower amounts of this substance in comparison with diploids. Also, we found such changes in protein concentration in electrophoresis analysis. In overall, our study suggests that tetraploidization could not be useful to produce tetrahydrocannabinol for commercial use, and in this case, mixoploids are more suitable.

  10. DNA as a phosphate storage polymer and the alternative advantages of polyploidy for growth or survival.

    PubMed

    Zerulla, Karolin; Chimileski, Scott; Näther, Daniela; Gophna, Uri; Papke, R Thane; Soppa, Jörg

    2014-01-01

    Haloferax volcanii uses extracellular DNA as a source for carbon, nitrogen, and phosphorous. However, it can also grow to a limited extend in the absence of added phosphorous, indicating that it contains an intracellular phosphate storage molecule. As Hfx. volcanii is polyploid, it was investigated whether DNA might be used as storage polymer, in addition to its role as genetic material. It could be verified that during phosphate starvation cells multiply by distributing as well as by degrading their chromosomes. In contrast, the number of ribosomes stayed constant, revealing that ribosomes are distributed to descendant cells, but not degraded. These results suggest that the phosphate of phosphate-containing biomolecules (other than DNA and RNA) originates from that stored in DNA, not in rRNA. Adding phosphate to chromosome depleted cells rapidly restores polyploidy. Quantification of desiccation survival of cells with different ploidy levels showed that under phosphate starvation Hfx. volcanii diminishes genetic advantages of polyploidy in favor of cell multiplication. The consequences of the usage of genomic DNA as phosphate storage polymer are discussed as well as the hypothesis that DNA might have initially evolved in evolution as a storage polymer, and the various genetic benefits evolved later. PMID:24733558

  11. Overexpression of CAP1 and its significance in tumor cell proliferation, migration and invasion in glioma.

    PubMed

    Fan, Yue-Chao; Cui, Chen-Chen; Zhu, Yi-Shuo; Zhang, Lei; Shi, Meng; Yu, Jin-Song; Bai, Jin; Zheng, Jun-Nian

    2016-09-01

    Adenylate cyclase-associated protein 1 (CAP1), a protein related to the regulation of actin filaments and the Ras/cAMP pathway, is associated with tumor progression. Nevertheless, the expression level and effects of CAP1 in regards to glioma have not been reported. In the present study, we examined the expression of CAP1 in glioma and tumor adjacent normal brain tissues by tissue microarray and immunohistochemistry. Our results showed that CAP1 was overexpressed in glioma tissues in comparison with that noted in the tumor adjacent normal brain tissues and increased staining of CAP1 was found to be correlated with WHO stage. In addition, we discovered that knockdown of CAP1 by specific RNA interference markedly inhibited cell growth and caused downregulation of the proliferation markers, PCNA and cyclin A. We further demonstrated that knockdown of CAP1 inhibited cell metastatic abilities by downregulating N-cadherin and vimentin and upregulating E-cadherin. These findings revealed that CAP1 expression is markedly increased in human glioma and that downregulation of CAP1 in tumors may serve as a treatment for glioma patients. PMID:27432289

  12. Maximum recovery potential of human tumor cells may predict clinical outcome in radiotherapy

    SciTech Connect

    Weichselbaum, R.R.; Beckett, M.

    1987-05-01

    We studied inherent radiosensitivity/resistance (D0), ability to accumulate sublethal damage (n) and repair of potentially lethal damage (PLDR) in established human tumor cell lines as well as early passage human tumor cell lines derived from patients with known outcome following radiotherapy. Survival 24 hrs after treatment of human tumor cells with X rays in plateau phase cultures is a function of initial damage (D0, n), as well as recovery over 24 hrs (PLDR). A surviving fraction greater than .1 24 hrs following treatment with 7 Gy in plateau phase cultures is associated with tumor cell types (melanoma, osteosarcoma) with a high probability of radiotherapy failure or tumor cells derived from patients who actually failed radiotherapy. Therefore, total cellular recovery following radiation may be an important determinant of radiocurability. Accurate assays of radiotherapy outcome may need to account for all these radiobiological parameters.

  13. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs.

    PubMed

    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-04-02

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors.

  14. Reduced mtDNA copy number increases the sensitivity of tumor cells to chemotherapeutic drugs

    PubMed Central

    Mei, H; Sun, S; Bai, Y; Chen, Y; Chai, R; Li, H

    2015-01-01

    Many cancer drugs are toxic to cells by activating apoptotic pathways. Previous studies have shown that mitochondria have key roles in apoptosis in mammalian cells, but the role of mitochondrial DNA (mtDNA) copy number variation in the pathogenesis of tumor cell apoptosis remains largely unknown. We used the HEp-2, HNE2, and A549 tumor cell lines to explore the relationship between mtDNA copy number variation and cell apoptosis. We first induced apoptosis in three tumor cell lines and one normal adult human skin fibroblast cell line (HSF) with cisplatin (DDP) or doxorubicin (DOX) treatment and found that the mtDNA copy number significantly increased in apoptotic tumor cells, but not in HSF cells. We then downregulated the mtDNA copy number by transfection with shRNA-TFAM plasmids or treatment with ethidium bromide and found that the sensitivity of tumor cells to DDP or DOX was significantly increased. Furthermore, we observed that levels of reactive oxygen species (ROS) increased significantly in tumor cells with lower mtDNA copy numbers, and this might be related to a low level of antioxidant gene expression. Finally, we rescued the increase of ROS in tumor cells with lipoic acid or N-acetyl-L-cysteine and found that the apoptosis rate decreased. Our studies suggest that the increase of mtDNA copy number is a self-protective mechanism of tumor cells to prevent apoptosis and that reduced mtDNA copy number increases ROS levels in tumor cells, increases the tumor cells' sensitivity to chemotherapeutic drugs, and increases the rate of apoptosis. This research provides evidence that mtDNA copy number variation might be a promising new therapeutic target for the clinical treatment of tumors. PMID:25837486

  15. Microchip-based immunomagnetic detection of circulating tumor cells.

    PubMed

    Hoshino, Kazunori; Huang, Yu-Yen; Lane, Nancy; Huebschman, Michael; Uhr, Jonathan W; Frenkel, Eugene P; Zhang, Xiaojing

    2011-10-21

    Screening for circulating tumor cells (CTCs) in blood has been an object of interest for evidence of progressive disease, status of disease activity, recognition of clonal evolution of molecular changes and for possible early diagnosis of cancer. We describe a new method of microchip-based immunomagnetic CTC detection, in which the benefits of both immunomagnetic assay and the microfluidic device are combined. As the blood sample flows through the microchannel closely above arrayed magnets, cancer cells labeled with magnetic nanoparticles are separated from blood flow and deposited at the bottom wall of the glass coverslip, which allows direct observation of captured cells with a fluorescence microscope. A polydimethylsiloxane (PDMS)-based microchannel fixed on a glass coverslip was used to screen blood samples. The thin, flat dimensions of the microchannel, combined with the sharp magnetic field gradient in the vicinity of arrayed magnets with alternate polarities, lead to an effective capture of labeled cells. Compared to the commercially available CellSearch™ system, fewer (25%) magnetic particles are required to achieve a comparable capture rate, while the screening speed (at an optimal blood flow rate of 10 mL h(-1)) is more than five times faster than those reported previously with a microchannel-based assay. For the screening experiment, blood drawn from healthy subjects into CellSave™ tubes was spiked with cultured cancer cell lines of COLO205 and SKBR3. The blood was then kept at room temperature for 48 hours before the screening, emulating the actual clinical cases of blood screening. Customized Fe(3)O(4) magnetic nanoparticles (Veridex Ferrofluid™) conjugated to anti-epithelial cell adhesion molecule (EpCAM) antibodies were introduced into the blood samples to label cancer cells, and the blood was then run through the microchip device to capture the labelled cells. After capture, the cells were stained with fluorescent labelled anti

  16. The Janus Face of Lipids in Human Breast Cancer: How Polyunsaturated Fatty Acids Affect Tumor Cell Hallmarks

    PubMed Central

    Chénais, Benoît; Blanckaert, Vincent

    2012-01-01

    For several years, lipids and especially n − 3 and n − 6 polyunsaturated fatty acids (PUFAs) receive much attention in human health. Epidemiological studies tend to correlate a PUFA-rich diet with a reduced incidence of cancer, including breast cancer. However, the molecular and cellular mechanisms supporting the effect of PUFAs in breast cancer cells remain relatively unknown. Here, we review some recent progress in understanding the impact that PUFA may have on breast cancer cell proliferation, apoptosis, migration, and invasion. While most of the results obtained with docosahexaenoic acid and/or eicosapentaenoic acid show a decrease of tumor cell proliferation and/or aggressivity, there is some evidence that other lipids, which accumulate in breast cancer tissues, such as arachidonic acid may have opposite effects. Finally, lipids and especially PUFAs appear as potential adjuvants to conventional cancer therapy. PMID:22811918

  17. Circulating tumor cells are correlated with disease progression and treatment response in an orthotopic hepatocellular carcinoma model.

    PubMed

    Yan, Jun; Fan, Zhichao; Wu, Xiufeng; Xu, Min; Jiang, Jiahao; Tan, Changjun; Wu, Weizhong; Wei, Xunbin; Zhou, Jian

    2015-11-01

    Hepatocellular carcinoma (HCC) is a highly malignant tumor characterized by rapid progression, poor prognosis, and frequent hematogenous metastasis. A minimally invasive diagnostic biomarker that can predict disease progression and treatment response would be of extraordinary benefit. Therefore, we have investigated whether the number of circulating tumor cells (CTCs) is correlated with disease progression and treatment response in HCC. Here we report that the number of CTCs, monitored by in vivo flow cytometry (IVFC), is strongly correlated with disease progression and treatment response in a highly metastatic orthotopic nude mouse model of green fluorescent protein (GFP)-labeled HCC. Sorafenib treatment reduces the number of CTCs significantly. The decreased number of CTCs is consistent with low lung metastasis. This study has demonstrated a considerable clinical value of CTCs as a biomarker in predicting disease progression and monitoring therapeutic efficacy in patients with HCC.

  18. Breast cancer cell behaviors on staged tumorigenesis-mimicking matrices derived from tumor cells at various malignant stages

    SciTech Connect

    Hoshiba, Takashi; Tanaka, Masaru

    2013-09-20

    Highlights: •Models mimicking ECM in tumor with different malignancy were prepared. •Cancer cell proliferation was suppressed on benign tumor ECM. •Benign tumor cell proliferation was suppressed on cancerous ECM. •Chemoresistance of cancer cell was enhanced on cancerous ECM. -- Abstract: Extracellular matrix (ECM) has been focused to understand tumor progression in addition to the genetic mutation of cancer cells. Here, we prepared “staged tumorigenesis-mimicking matrices” which mimic in vivo ECM in tumor tissue at each malignant stage to understand the roles of ECM in tumor progression. Breast tumor cells, MDA-MB-231 (invasive), MCF-7 (non-invasive), and MCF-10A (benign) cells, were cultured to form their own ECM beneath the cells and formed ECM was prepared as staged tumorigenesis-mimicking matrices by decellularization treatment. Cells showed weak attachment on the matrices derived from MDA-MB-231 cancer cells. The proliferations of MDA-MB-231 and MCF-7 was promoted on the matrices derived from MDA-MB-231 cancer cells whereas MCF-10A cell proliferation was not promoted. MCF-10A cell proliferation was promoted on the matrices derived from MCF-10A cells. Chemoresistance of MDA-MB-231 cells against 5-fluorouracil increased on only matrices derived from MDA-MB-231 cells. Our results showed that the cells showed different behaviors on staged tumorigenesis-mimicking matrices according to the malignancy of cell sources for ECM preparation. Therefore, staged tumorigenesis-mimicking matrices might be a useful in vitro ECM models to investigate the roles of ECM in tumor progression.

  19. Whole genome duplication in coast redwood (Sequoia sempervirens) and its implications for explaining the rarity of polyploidy in conifers.

    PubMed

    Scott, Alison Dawn; Stenz, Noah W M; Ingvarsson, Pär K; Baum, David A

    2016-07-01

    Polyploidy is common and an important evolutionary factor in most land plant lineages, but it is rare in gymnosperms. Coast redwood (Sequoia sempervirens) is one of just two polyploid conifer species and the only hexaploid. Evidence from fossil guard cell size suggests that polyploidy in Sequoia dates to the Eocene. Numerous hypotheses about the mechanism of polyploidy and parental genome donors have been proposed, based primarily on morphological and cytological data, but it remains unclear how Sequoia became polyploid and why this lineage overcame an apparent gymnosperm barrier to whole-genome duplication (WGD). We sequenced transcriptomes and used phylogenetic inference, Bayesian concordance analysis and paralog age distributions to resolve relationships among gene copies in hexaploid coast redwood and close relatives. Our data show that hexaploidy in coast redwood is best explained by autopolyploidy or, if there was allopolyploidy, it happened within the Californian redwood clade. We found that duplicate genes have more similar sequences than expected, given the age of the inferred polyploidization. Conflict between molecular and fossil estimates of WGD can be explained if diploidization occurred very slowly following polyploidization. We extrapolate from this to suggest that the rarity of polyploidy in gymnosperms may be due to slow diploidization in this clade.

  20. Whole genome duplication in coast redwood (Sequoia sempervirens) and its implications for explaining the rarity of polyploidy in conifers.

    PubMed

    Scott, Alison Dawn; Stenz, Noah W M; Ingvarsson, Pär K; Baum, David A

    2016-07-01

    Polyploidy is common and an important evolutionary factor in most land plant lineages, but it is rare in gymnosperms. Coast redwood (Sequoia sempervirens) is one of just two polyploid conifer species and the only hexaploid. Evidence from fossil guard cell size suggests that polyploidy in Sequoia dates to the Eocene. Numerous hypotheses about the mechanism of polyploidy and parental genome donors have been proposed, based primarily on morphological and cytological data, but it remains unclear how Sequoia became polyploid and why this lineage overcame an apparent gymnosperm barrier to whole-genome duplication (WGD). We sequenced transcriptomes and used phylogenetic inference, Bayesian concordance analysis and paralog age distributions to resolve relationships among gene copies in hexaploid coast redwood and close relatives. Our data show that hexaploidy in coast redwood is best explained by autopolyploidy or, if there was allopolyploidy, it happened within the Californian redwood clade. We found that duplicate genes have more similar sequences than expected, given the age of the inferred polyploidization. Conflict between molecular and fossil estimates of WGD can be explained if diploidization occurred very slowly following polyploidization. We extrapolate from this to suggest that the rarity of polyploidy in gymnosperms may be due to slow diploidization in this clade. PMID:26996245

  1. Effects of Charged Particles on Human Tumor Cells

    PubMed Central

    Held, Kathryn D.; Kawamura, Hidemasa; Kaminuma, Takuya; Paz, Athena Evalour S.; Yoshida, Yukari; Liu, Qi; Willers, Henning; Takahashi, Akihisa

    2016-01-01

    The use of charged particle therapy in cancer treatment is growing rapidly, in large part because the exquisite dose localization of charged particles allows for higher radiation doses to be given to tumor tissue while normal tissues are exposed to lower doses and decreased volumes of normal tissues are irradiated. In addition, charged particles heavier than protons have substantial potential clinical advantages because of their additional biological effects, including greater cell killing effectiveness, decreased radiation resistance of hypoxic cells in tumors, and reduced cell cycle dependence of radiation response. These biological advantages depend on many factors, such as endpoint, cell or tissue type, dose, dose rate or fractionation, charged particle type and energy, and oxygen concentration. This review summarizes the unique biological advantages of charged particle therapy and highlights recent research and areas of particular research needs, such as quantification of relative biological effectiveness (RBE) for various tumor types and radiation qualities, role of genetic background of tumor cells in determining response to charged particles, sensitivity of cancer stem-like cells to charged particles, role of charged particles in tumors with hypoxic fractions, and importance of fractionation, including use of hypofractionation, with charged particles. PMID:26904502

  2. Regulation of Proliferation-Survival Decisions during Tumor Cell Hypoxia

    PubMed Central

    Schmaltz, Cornelius; Hardenbergh, Patricia Harrigan; Wells, Audrey; Fisher, David E.

    1998-01-01

    Hypoxia may influence tumor biology in paradoxically opposing ways: it is lethal as a direct stress trigger, yet hypoxic zones in solid tumors harbor viable cells which are particularly resistant to treatment and contribute importantly to disease relapse. To examine mechanisms underlying growth-survival decisions during hypoxia, we have compared genetically related transformed and untransformed fibroblast cells in vitro for proliferation, survival, clonogenicity, cell cycle, and p53 expression. Hypoxia induces G0/G1 arrest in primary fibroblasts but triggers apoptosis in oncogene-transformed derivatives. Unexpectedly, the mechanism of apoptosis is seen to require accumulated acidosis and is rescued by enhanced buffering. The direct effect of hypoxia under nonacidotic conditions is unique to transformed cells in that they override the hypoxic G0/G1 arrest of primary cells. Moreover, when uncoupled from acidosis, hypoxia enhances tumor cell viability and clonogenicity relative to normoxia. p53 is correspondingly upregulated in response to hypoxia-induced acidosis but downregulated during hypoxia without acidosis. Hypoxia may thus produce both treatment resistance and a growth advantage. Given strong evidence that hypoxic regions in solid tumors are often nonacidotic (G. Helmlinger, F. Yuan, M. Dellian, and R. K. Jain, Nat. Med. 3:177–182, 1997), this behavior may influence relapse and implicates such cells as potentially important therapeutic targets. PMID:9566903

  3. Fractal Dimensions of In Vitro Tumor Cell Proliferation

    PubMed Central

    Lambrou, George I.

    2015-01-01

    Biological systems are characterized by their potential for dynamic adaptation. One of the challenges for systems biology approaches is their contribution towards the understanding of the dynamics of a growing cell population. Conceptualizing these dynamics in tumor models could help us understand the steps leading to the initiation of the disease and its progression. In vitro models are useful in answering this question by providing information over the spatiotemporal nature of such dynamics. In the present work, we used physical quantities such as growth rate, velocity, and acceleration for the cellular proliferation and identified the fractal structures in tumor cell proliferation dynamics. We provide evidence that the rate of cellular proliferation is of nonlinear nature and exhibits oscillatory behavior. We also calculated the fractal dimensions of our cellular system. Our results show that the temporal transitions from one state to the other also follow nonlinear dynamics. Furthermore, we calculated self-similarity in cellular proliferation, providing the basis for further investigation in this topic. Such systems biology approaches are very useful in understanding the nature of cellular proliferation and growth. From a clinical point of view, our results may be applicable not only to primary tumors but also to tumor metastases. PMID:25883653

  4. Nanotechnology for the detection and kill of circulating tumor cells

    PubMed Central

    2014-01-01

    Circulating tumor cells (CTCs) represent a surrogate biomarker of hematogenous metastases and thus could be considered as a ‘liquid biopsy’ which reveals metastasis in action. But it is absolutely a challenge to detect CTCs due to their extreme rarity. At present, the most common principle is to take advantage of the epithelial surface markers of CTCs which attach to a specific antibody. Antibody-magnetic nanobeads combine with the epithelial surface markers, and then the compound is processed by washing, separation, and detection. However, a proportion of CTC antigen expressions are down-regulated or lost in the process of epithelial-mesenchymal transition (EMT), and thus, this part of CTCs cannot be detected by classical detection methods such as CellSearch. To resolve this problem, some multiple-marker CTC detections have been developed rapidly. Additionally, nanotechnology is a promising approach to kill CTCs with high efficiency. Implantable nanotubes coated with apoptosis-promoting molecules improve the disease-free survival and overall survival. The review introduces some novel CTC detection techniques and therapeutic methods by virtue of nanotechnology to provide a better knowledge of the progress about CTC study. PMID:25258614

  5. Immunonanoshells for targeted photothermal ablation of tumor cells

    PubMed Central

    Lowery, Amanda R; Gobin, André M; Day, Emily S; Halas, Naomi J; West, Jennifer L

    2006-01-01

    Consisting of a silica core surrounded by a thin gold shell, nanoshells possess an optical tunability that spans the visible to the near infrared (NIR) region, a region where light penetrates tissues deeply. Conjugated with tumor-specific antibodies, NIR-absorbing immunonanoshells can preferentially bind to tumor cells. NIR light then heats the bound nanoshells, thus destroying the targeted cells. Antibodies can be consistently bound to the nanoshells via a bifunctional polyethylene glycol (PEG) linker at a density of ~150 antibodies per nanoshell. In vitro studies have confirmed the ability to selectively induce cell death with the photothermal interaction of immunonanoshells and NIR light. Prior to incubation with anti-human epidermal growth factor receptor (HER2) immunonanoshells, HER2-expressing SK-BR-3 breast carcinoma cells were seeded alone or adjacent to human dermal fibroblasts (HDFs). Anti-HER2 immunonanoshells bound to HER2-expressing cells resulted in the death of SK-BR-3 cells after NIR exposure only within the irradiated area, while HDFs remained viable after similar treatment since the immunonanoshells did not bind to these cells at high levels. Control nanoshells, conjugated with nonspecific anti-IgG or PEG, did not bind to either cell type, and cells continued to be viable after treatment with these control nanoshells and NIR irradiation. PMID:17722530

  6. Autologous tumor cells engineered to express bacterial antigens.

    PubMed

    Ramiya, Vijayakumar K; Jerald, Maya M; Lawman, Patricia D; Lawman, Michael J P

    2014-01-01

    Cancer immunotherapies are emerging as promising treatment modalities in the management of the disease. As a result, cancer vaccines are considered to be immensely crucial in preventing recurrence, a well-known nemesis in cancer patients because they have the potential to activate memory antitumor immunity. Due to poor antigenicity and self-tolerance, most tumor antigens require interventional vaccine therapies to provide an adequate "danger" signal to the immune system in order to activate a robust, clinically meaningful antitumor immunity. It has been postulated that this requirement may be achieved by providing bacterial and/or viral immunogens to prime this type of immune response. Briefly, we provide here a method of transfecting whole tumor cells with plasmid DNA encoding an immunogenic bacterial protein such as Emm55, which was derived from Streptococcus pyogenes (S. pyogenes). Subsequent inactivation of the transfected cells by irradiation (100 Gray) prevents replication. This type of whole-cell vaccine, e.g., ImmuneFx™, has demonstrated activity in a murine neuroblastoma model, in canine lymphoma patients with naturally occurring disease, and in many cancer types in companion animals. The protocols described in this chapter provide the necessary materials and methodologies to manufacture such a vaccine.

  7. Electrical Detection Method for Circulating Tumor Cells Using Graphene Nanoplates.

    PubMed

    Han, Song-I; Han, Ki-Ho

    2015-10-20

    This paper presents a microfluidic device for electrical discrimination of circulating tumor cells (CTCs) using graphene nanoplates (GNPs) as a highly conductive material bound to the cell surface. For two-step cascade discrimination, the microfluidic device is composed of a CTC-enrichment device and an impedance cytometry. Using lateral magnetophoresis, the CTC-enrichment device enriches rare CTCs from millions of background blood cells. Then, the impedance cytometry electrically identifies CTCs from the enriched sample, containing CTCs and persistent residual blood cells, based on the electrical impedance of CTCs modified by the GNPs. GNPs were used as a highly conductive material for modifying surface conductivity of CTCs, thereby improving the accuracy of electrical discrimination. The experimental results showed that a colorectal cancer cell line (DLD-1) spiked into peripheral blood was enriched by nearly 500-fold by the CTC-enrichment device. The phase of the electrical signal measured from DLD-1 cells covered by GNPs shifted by about 100° in comparison with that from normal blood cells, which allows the impedance cytometry to identify CTCs at a rate of 94% from the enriched samples. PMID:26402053

  8. Specific Visualization of Tumor Cells Using Upconversion Nanophosphors

    PubMed Central

    Grebenik, E. A.; Generalova, A. N.; Nechaev, A. V.; Khaydukov, E.V.; Mironova, K. E.; Stremovskiy, O. A.; Lebedenko, E.N.; Zvyagin, A. V.; Deyev, S. M.

    2014-01-01

    The development of targeted constructs on the basis of photoluminescent nanoparticles with a high photo- and chemical stability and absorption/emission spectra in the “transparency window” of biological tissues is an important focus area of present-day medical diagnostics. In this work, a targeted two-component construct on the basis of upconversion nanophosphors (UCNPs) and anti-tumor 4D5 scFv was developed for selective labeling of tumor cells overexpressing the HER2 tumor marker characteristic of a number of human malignant tumors. A high affinity barnase : barstar (Bn : Bs) protein pair, which exhibits high stability in a wide range of pH and temperatures, was exploited as a molecular adapter providing self-assembly of the two-component construct. High selectivity for the binding of the two-component 4D5 scFv-Bn : UCNP-Bs construct to human breast adenocarcinoma SK-BR-3 cells overexpressing HER2 was demonstrated. This approach provides an opportunity to produce similar constructs for the visualization of different specific markers in pathogenic tissues, including malignant tumors. PMID:25558394

  9. Interaction of tumor cells and lymphatic vessels in cancer progression.

    PubMed

    Alitalo, A; Detmar, M

    2012-10-18

    Metastatic spread of cancer through the lymphatic system affects hundreds of thousands of patients yearly. Growth of new lymphatic vessels, lymphangiogenesis, is activated in cancer and inflammation, but is largely inactive in normal physiology, and therefore offers therapeutic potential. Key mediators of lymphangiogenesis have been identified in developmental studies. During embryonic development, lymphatic endothelial cells derive from the blood vascular endothelium and differentiate under the guidance of lymphatic-specific regulators, such as the prospero homeobox 1 transcription factor. Vascular endothelial growth factor-C (VEGF-C) and VEGF receptor 3 signaling are essential for the further development of lymphatic vessels and therefore they provide a promising target for inhibition of tumor lymphangiogenesis. Lymphangiogenesis is important for the progression of solid tumors as shown for melanoma and breast cancer. Tumor cells may use chemokine gradients as guidance cues and enter lymphatic vessels through intercellular openings between endothelial cell junctions or, possibly, by inducing larger discontinuities in the endothelial cell layer. Tumor-draining sentinel lymph nodes show enhanced lymphangiogenesis even before cancer metastasis and they may function as a permissive 'lymphovascular niche' for the survival of metastatic cells. Although our current knowledge indicates that the development of anti-lymphangiogenic therapies may be beneficial for the treatment of cancer patients, several open questions remain with regard to the frequency, mechanisms and biological importance of lymphatic metastases.

  10. Transport Mechanisms of Circulating Tumor Cells in Microfluidic Devices

    NASA Astrophysics Data System (ADS)

    Rangharajan, Kaushik; Conlisk, A. T.; Prakash, Shaurya

    2014-11-01

    Lab-on-a-chip (LoC) devices are becoming an essential tool for several emerging point-of-care healthcare needs and applications. Among the plethora of challenging problems in the personalized healthcare domain, early detection of cancer continues to be a challenge. For instance, identification of most tumors occurs by the time the tumor comprises approximately 1 billion cells, with poor prognosis for metastatic disease. The key obstacle in identifying and subsequent capture of circulating tumor cells (CTCs) is that the amount of CTCs in the blood stream is ~1 in 109 cells. The fundamental challenge in design and fabrication of microfluidic devices arises due to lack of information on suitable sorting needed for sample preparation before any labeling or capture scheme can be employed. Moreover, the ability to study these low concentration cells relies on knowledge of their physical and chemical properties, of which the physical properties are poorly understood. Also, nearly all existing microfluidic mixers were developed for aqueous electrolyte solutions to enhance mixing in traditional low Re flows. However, no systematic studies have developed design rules for particle mixing. Therefore, we present a numerical model to discuss design rules for microscale mixers and sorters for particle sorting for high efficiency antibody labeling of CTCs along with presenting a pathway for a device to capture CTCs without the need for labeling based on particle electrical properties. NSF Nanoscale Science and Engineering Center (NSEC) for the Affordable Nanoengineering of Polymeric Biomedical Devices EEC-0914790.

  11. Nanotechnology for the detection and kill of circulating tumor cells

    NASA Astrophysics Data System (ADS)

    Gao, Yang; Yuan, Zhou

    2014-09-01

    Circulating tumor cells (CTCs) represent a surrogate biomarker of hematogenous metastases and thus could be considered as a `liquid biopsy' which reveals metastasis in action. But it is absolutely a challenge to detect CTCs due to their extreme rarity. At present, the most common principle is to take advantage of the epithelial surface markers of CTCs which attach to a specific antibody. Antibody-magnetic nanobeads combine with the epithelial surface markers, and then the compound is processed by washing, separation, and detection. However, a proportion of CTC antigen expressions are down-regulated or lost in the process of epithelial-mesenchymal transition (EMT), and thus, this part of CTCs cannot be detected by classical detection methods such as CellSearch. To resolve this problem, some multiple-marker CTC detections have been developed rapidly. Additionally, nanotechnology is a promising approach to kill CTCs with high efficiency. Implantable nanotubes coated with apoptosis-promoting molecules improve the disease-free survival and overall survival. The review introduces some novel CTC detection techniques and therapeutic methods by virtue of nanotechnology to provide a better knowledge of the progress about CTC study.

  12. Collective behavior of brain tumor cells: The role of hypoxia

    NASA Astrophysics Data System (ADS)

    Khain, Evgeniy; Katakowski, Mark; Hopkins, Scott; Szalad, Alexandra; Zheng, Xuguang; Jiang, Feng; Chopp, Michael

    2011-03-01

    We consider emergent collective behavior of a multicellular biological system. Specifically, we investigate the role of hypoxia (lack of oxygen) in migration of brain tumor cells. We performed two series of cell migration experiments. In the first set of experiments, cell migration away from a tumor spheroid was investigated. The second set of experiments was performed in a typical wound-healing geometry: Cells were placed on a substrate, a scratch was made, and cell migration into the gap was investigated. Experiments show a surprising result: Cells under normal and hypoxic conditions have migrated the same distance in the “spheroid” experiment, while in the “scratch” experiment cells under normal conditions migrated much faster than under hypoxic conditions. To explain this paradox, we formulate a discrete stochastic model for cell dynamics. The theoretical model explains our experimental observations and suggests that hypoxia decreases both the motility of cells and the strength of cell-cell adhesion. The theoretical predictions were further verified in independent experiments.

  13. Photoacoustic monitoring of circulating tumor cells released during medical procedures

    NASA Astrophysics Data System (ADS)

    Juratli, Mazen A.; Sarimollaoglu, Mustafa; Nedosekin, Dmitry A.; Galanzha, Ekaterina; Suen, James Y.; Zharov, Vladimir P.

    2013-03-01

    Many cancer deaths are related to metastasis to distant organs due to dissemination of circulating tumor cells (CTCs) shed from the primary tumor. For many years, oncologists believed some medical procedures may provoke metastasis; however, no direct evidence has been reported. We have developed a new, noninvasive technology called in vivo photoacoustic (PA) flow cytometry (PAFC), which provides ultrasensitive detection of CTCs. When CTCs with strongly light-absorbing intrinsic melanin pass through a laser beam aimed at a peripheral blood vessel, laser-induced acoustic waves from CTCs were detected using an ultrasound transducer. We focused on melanoma as it is one of the most metastatically aggressive malignancies. The goal of this research was to determine whether melanoma manipulation, like compression, incisional biopsy, or tumor excision, could enhance penetration of cancer cells from the primary tumor into the circulatory system. The ears of nude mice were inoculated with melanoma cells. Blood vessels were monitored for the presence of CTCs using in vivo PAFC. We discovered some medical procedures, like compression of the tumor, biopsy, and surgery may either initiate CTC release in the blood which previously contained no CTCs, or dramatically increased (10-30-fold) CTC counts above the initial level. Our results warn oncologists to use caution during physical examination, and surgery. A preventive anti-CTC therapy during or immediately after surgery, by intravenous drug administration could serve as an option to treat the resulting release of CTCs.

  14. Detection and isolation of circulating tumor cells: principles and methods.

    PubMed

    Esmaeilsabzali, Hadi; Beischlag, Timothy V; Cox, Michael E; Parameswaran, Ash M; Park, Edward J

    2013-11-15

    Efforts to improve the clinical management of several cancers include finding better methods for the quantitative and qualitative analysis of circulating tumor cells (CTCs). However, detection and isolation of CTCs from the blood circulation is not a trivial task given their scarcity and the lack of reliable markers to identify these cells. With a variety of emerging technologies, a thorough review of the exploited principles and techniques as well as the trends observed in the development of these technologies can assist researchers to recognize the potential improvements and alternative approaches. To help better understand the related biological concepts, a simplified framework explaining cancer formation and its spread to other organs as well as how CTCs contribute to this process has been presented first. Then, based on their basic working-principles, the existing methods for detection and isolation of CTCs have been classified and reviewed as nucleic acid-based, physical properties-based and antibody-based methods. The review of literature suggests that antibody-based methods, particularly in conjunction with a microfluidic lab-on-a-chip setting, offer the highest overall performance for detection and isolation of CTCs. Further biological and engineering-related research is required to improve the existing methods. These include finding more specific markers for CTCs as well as enhancing the throughput, sensitivity, and analytic functionality of current devices.

  15. Circulating tumor cell detection using photoacoustic spectral methods

    NASA Astrophysics Data System (ADS)

    Strohm, Eric M.; Berndl, Elizabeth S. L.; Kolios, Michael C.

    2014-03-01

    A method to detect and differentiate circulating melanoma tumor cells (CTCs) from blood cells using ultrasound and photoacoustic signals with frequencies over 100 MHz is presented. At these frequencies, the acoustic wavelength is similar to the dimensions of a cell, which results in unique features in the signal; periodically varying minima and maxima occur throughout the power spectrum. The spacing between minima depends on the ratio of the size to sound speed of the cell. Using a 532 nm pulsed laser and a 375 MHz center frequency wide-bandwidth transducer, the ultrasound and photoacoustic signals were measured from single cells. A total of 80 cells were measured, 20 melanoma cells, 20 white blood cells (WBCs) and 40 red blood cells (RBCs). The photoacoustic spectral spacing Δf between minima was 95 +/- 15 MHz for melanoma cells and greater than 230 MHz for RBCs. No photoacoustic signal was detected from WBCs. The ultrasonic spectral spacing between minima was 46 +/- 9 MHz for melanoma cells and 98 +/- 11 for WBCs. Both photoacoustic and ultrasound signals were detected from melanoma cells, while only ultrasound signals were detected from WBCs. RBCs showed distinct photoacoustic spectral variations in comparison to any other type of cell. Using the spectral spacing and signal amplitudes, each cell type could be grouped together to aid in cell identification. This method could be used for label-free counting and classifying cells in a sample.

  16. Dynamic Fluctuation of Circulating Tumor Cells during Cancer Progression.

    PubMed

    Juratli, Mazen A; Sarimollaoglu, Mustafa; Nedosekin, Dmitry A; Melerzanov, Alexander V; Zharov, Vladimir P; Galanzha, Ekaterina I

    2014-01-01

    Circulating tumor cells (CTCs) are a promising diagnostic and prognostic biomarker for metastatic tumors. We demonstrate that CTCs' diagnostic value might be increased through real-time monitoring of CTC dynamics. Using preclinical animal models of breast cancer and melanoma and in vivo flow cytometry with photoacoustic and fluorescence detection schematics, we show that CTC count does not always correlate with the primary tumor size. Individual analysis elucidated many cases where the highest level of CTCs was detected before the primary tumor starts progressing. This phenomenon could be attributed to aggressive tumors developing from cancer stem cells. Furthermore, real-time continuous monitoring of CTCs reveals that they occur at highly variable rates in a detection point over a period of time (e.g., a range of 0-54 CTCs per 5 min). These same fluctuations in CTC numbers were observed in vivo in epithelial and non-epithelial metastatic tumors, in different stages of tumor progression, and in different vessels. These temporal CTC fluctuations can explain false negative results of a one-time snapshot test in humans. Indeed, we observed wide variations in the number of CTCs in subsequent blood samples taken from the same metastatic melanoma patient, with some samples being CTC-free. If these phenomena are confirmed in our ongoing in vivo clinical trials, this could support a personalized strategy of CTC monitoring for cancer patients. PMID:24434542

  17. Clusters of circulating tumor cells traverse capillary-sized vessels

    PubMed Central

    Au, Sam H.; Storey, Brian D.; Moore, John C.; Tang, Qin; Chen, Yeng-Long; Javaid, Sarah; Sarioglu, A. Fatih; Sullivan, Ryan; Madden, Marissa W.; O’Keefe, Ryan; Haber, Daniel A.; Maheswaran, Shyamala; Langenau, David M.; Stott, Shannon L.; Toner, Mehmet

    2016-01-01

    Multicellular aggregates of circulating tumor cells (CTC clusters) are potent initiators of distant organ metastasis. However, it is currently assumed that CTC clusters are too large to pass through narrow vessels to reach these organs. Here, we present evidence that challenges this assumption through the use of microfluidic devices designed to mimic human capillary constrictions and CTC clusters obtained from patient and cancer cell origins. Over 90% of clusters containing up to 20 cells successfully traversed 5- to 10-μm constrictions even in whole blood. Clusters rapidly and reversibly reorganized into single-file chain-like geometries that substantially reduced their hydrodynamic resistances. Xenotransplantation of human CTC clusters into zebrafish showed similar reorganization and transit through capillary-sized vessels in vivo. Preliminary experiments demonstrated that clusters could be disrupted during transit using drugs that affected cellular interaction energies. These findings suggest that CTC clusters may contribute a greater role to tumor dissemination than previously believed and may point to strategies for combating CTC cluster-initiated metastasis. PMID:27091969

  18. Interpretation of Changes in Circulating Tumor Cell Counts12

    PubMed Central

    Coumans, Frank AW; Ligthart, Sjoerd T; Terstappen, Leon WMM

    2012-01-01

    The presence of circulating tumor cells (CTCs) in the blood of cancer patients may guide the use of therapy. We investigated how to evaluate a reduction in the number of CTCs after administration of therapy. CTCs were enumerated with the CellSearch system in 111 metastatic breast and 185 metastatic prostate cancer patients before start of a new line of chemotherapy and after initiation of therapy. Different means to express changes in CTC counts were evaluated with respect to overall survival (OS). A static CTC cutoff is the best method to determine whether a therapy is effective. This is exemplified by the highest Cox hazard ratio of 2.1 for OS; three methods to express relative differences performed worse. A lookup table is provided from which the significance of a change in CTCs can be derived. The aim of therapy should be the elimination of all CTCs. A period of 10 to 12 weeks of therapy is needed to reach the treatment effect on CTCs. PMID:23323160

  19. Interpretation of changes in circulating tumor cell counts.

    PubMed

    Coumans, Frank Aw; Ligthart, Sjoerd T; Terstappen, Leon Wmm

    2012-12-01

    The presence of circulating tumor cells (CTCs) in the blood of cancer patients may guide the use of therapy. We investigated how to evaluate a reduction in the number of CTCs after administration of therapy. CTCs were enumerated with the CellSearch system in 111 metastatic breast and 185 metastatic prostate cancer patients before start of a new line of chemotherapy and after initiation of therapy. Different means to express changes in CTC counts were evaluated with respect to overall survival (OS). A static CTC cutoff is the best method to determine whether a therapy is effective. This is exemplified by the highest Cox hazard ratio of 2.1 for OS; three methods to express relative differences performed worse. A lookup table is provided from which the significance of a change in CTCs can be derived. The aim of therapy should be the elimination of all CTCs. A period of 10 to 12 weeks of therapy is needed to reach the treatment effect on CTCs.

  20. Role for histone deacetylase 1 in human tumor cell proliferation.

    PubMed

    Senese, Silvia; Zaragoza, Katrin; Minardi, Simone; Muradore, Ivan; Ronzoni, Simona; Passafaro, Alfonso; Bernard, Loris; Draetta, Giulio F; Alcalay, Myriam; Seiser, Christian; Chiocca, Susanna

    2007-07-01

    Posttranslational modifications of core histones are central to the regulation of gene expression. Histone deacetylases (HDACs) repress transcription by deacetylating histones, and class I HDACs have a crucial role in mouse, Xenopus laevis, zebra fish, and Caenorhabditis elegans development. The role of individual class I HDACs in tumor cell proliferation was investigated using RNA interference-mediated protein knockdown. We show here that in the absence of HDAC1 cells can arrest either at the G(1) phase of the cell cycle or at the G(2)/M transition, resulting in the loss of mitotic cells, cell growth inhibition, and an increase in the percentage of apoptotic cells. On the contrary, HDAC2 knockdown showed no effect on cell proliferation unless we concurrently knocked down HDAC1. Using gene expression profiling analysis, we found that inactivation of HDAC1 affected the transcription of specific target genes involved in proliferation and apoptosis. Furthermore, HDAC2 downregulation did not cause significant changes compared to control cells, while inactivation of HDAC1, HDAC1 plus HDAC2, or HDAC3 resulted in more distinct clusters. Loss of these HDACs might impair cell cycle progression by affecting not only the transcription of specific target genes but also other biological processes. Our data support the idea that a drug targeting specific HDACs could be highly beneficial in the treatment of cancer.

  1. The ADAMTS12 metalloprotease gene is epigenetically silenced in tumor cells and transcriptionally activated in the stroma during progression of colon cancer.

    PubMed

    Moncada-Pazos, Angela; Obaya, Alvaro J; Fraga, Mario F; Viloria, Cristina G; Capellá, Gabriel; Gausachs, Mireia; Esteller, Manel; López-Otín, Carlos; Cal, Santiago

    2009-08-15

    Proteases have long been associated with tumor progression, given their ability to degrade extracellular matrix components and facilitate invasion and metastasis. However, recent findings indicate that different proteases can also act as tumor-suppressor enzymes. We have recently reported that lung carcinoma cells expressing the ADAMTS-12 metalloprotease show a remarkable impairment of growth in immunodeficient mice as compared with parental cells. Here, we show that ADAMTS12 promoter is hypermethylated in cancer cell lines and tumor tissues. Interestingly, ADAMTS12 expression in the stromal cells surrounding epithelial malignant cells is higher than in the paired normal tissues. Moreover, the expression of this metalloprotease in colon fibroblasts co-cultured with colon cancer cell lines is higher than in those cultured alone. Furthermore, the expression of ADAMTS-12 by these fibroblasts is linked with an anti-proliferative effect on tumor cells. Based on these findings, we hypothesize that ADAMTS-12 is a novel anti-tumor protease that can reduce the proliferative properties of tumor cells. This function is lost by epigenetic silencing in tumor cells, but concurrently induced in stromal cells, probably as part of a response of the normal tissue aimed at controlling the progression of cancer.

  2. Novel cancer vaccines prepared by anchoring cytokines to tumor cells avoiding gene transfection

    NASA Astrophysics Data System (ADS)

    Nizard, Philippe; Gross, David-Alexandre; Chenal, Alexandre; Beaumelle, Bruno; Kosmatopoulos, Konstadinos; Gillet, Daniel

    2002-06-01

    Cytokines have a strong potential for triggering anticancer immunity if released in the tumor microenvironment. Successful vaccines have been engineered using tumor cells genetically modified to secrete the cytokines. Unfortunately, this approach remains difficult and hazardous to perform in the clinic. We describe a new way of combining cytokines with tumor cells to prepare anticancer vaccines. This consists in anchoring recombinant cytokines to the membrane of killed tumor cells. Attachment is mediated by a fragment of diphtheria toxin (T) genetically connected to the cytokine. It is triggered by an acid pH pulse. The method was applied to IL-2, a potent anti-tumor cytokine. IL-2 anchored to the surface of tumor cells by the T anchor retained its IL-2 activity and remained exposed several days. Interestingly, vaccination of mice with these modified tumor cells induced a protective anti-tumor immunity mediated by tumor-specific cytotoxic T lymphocytes. This procedure presents several advantages as compared to the conventional approaches based on the transfection of tumor cells with cytokine genes. It does not require the culture of tumor cells from the patients and eliminates the safety problems connected with viral vectors while allowing the control of the amount of cytokines delivered with the vaccine.

  3. X-ray responses of human colon tumor cells grown in artificial capillary culture

    SciTech Connect

    Nakazawa, M.; Leith, J.T.; Glicksman, A.S.

    1984-06-01

    Clone A human colon adenocarcinoma cells were grown in three-dimensional artificial capillary culture (ACC) to determine responses of capillaries treated 3 weeks after tumor cell inoculation with a specific, easily quantifiable cytotoxic agent, ionizing radiation. Changes in extracapillary space (ECS) fluid concentrations of lactate dehydrogenase (LDH) and aspartate aminotransferase (GOT) and the utilization of glucose in circulating medium were monitored after a supralethal radiation dose (90 Gy) of X-rays. Immediately after irradiation, increased levels of LDH and GOT were found that reached maximum levels about four to five times those found in nonirradiated control capillaries at 10-13 days post irradiation and then declined. Patterns of enzyme production appeared to correlate with the numbers of nonviable tumor cells collected from the ECS of the artificial capillaries. In contrast, glucose utilization showed little correlation with either enzyme concentration or dead cell production. In other studies, tumor cells were removed from unirradiated capillaries by trypsinization and used to obtain complete survival curves after graded doses of X-radiation. The dose-response curves obtained indicate that clone A colon tumor cells grown in ACC show a marked decrease in their ability to accumulate sublethal radiation injury as compared to responses of these cells growing exponentially in asynchronous monolayer cultures, to synchronized mid-G1 tumor cells, or to tumor cells in stationary growth phase. These data suggest that ACC is a potentially useful model to study the effects of cytotoxic agents on human tumor cells.

  4. Tumor cells disseminate early, but immunosurveillance limits metastatic outgrowth, in a mouse model of melanoma

    PubMed Central

    Eyles, Jo; Puaux, Anne-Laure; Wang, Xiaojie; Toh, Benjamin; Prakash, Celine; Hong, Michelle; Tan, Tze Guan; Zheng, Lin; Ong, Lai Chun; Jin, Yi; Kato, Masashi; Prévost-Blondel, Armelle; Chow, Pierce; Yang, Henry; Abastado, Jean-Pierre

    2010-01-01

    Although metastasis is the leading cause of cancer-related death, it is not clear why some patients with localized cancer develop metastatic disease after complete resection of their primary tumor. Such relapses have been attributed to tumor cells that disseminate early and remain dormant for prolonged periods of time; however, little is known about the control of these disseminated tumor cells. Here, we have used a spontaneous mouse model of melanoma to investigate tumor cell dissemination and immune control of metastatic outgrowth. Tumor cells were found to disseminate throughout the body early in development of the primary tumor, even before it became clinically detectable. The disseminated tumor cells remained dormant for varying periods of time depending on the tissue, resulting in staggered metastatic outgrowth. Dormancy in the lung was associated with reduced proliferation of the disseminated tumor cells relative to the primary tumor. This was mediated, at least in part, by cytostatic CD8+ T cells, since depletion of these cells resulted in faster outgrowth of visceral metastases. Our findings predict that immune responses favoring dormancy of disseminated tumor cells, which we propose to be the seed of subsequent macroscopic metastases, are essential for prolonging the survival of early stage cancer patients and suggest that therapeutic strategies designed to reinforce such immune responses may produce marked benefits in these patients. PMID:20501944

  5. Inhibition of tumor cell proliferation and motility by fibroblasts is both contact and soluble factor dependent

    PubMed Central

    Alkasalias, Twana; Flaberg, Emilie; Kashuba, Vladimir; Alexeyenko, Andrey; Pavlova, Tatiana; Savchenko, Andrii; Szekely, Laszlo; Klein, George; Guven, Hayrettin

    2014-01-01

    Normal human and murine fibroblasts can inhibit proliferation of tumor cells when cocultured in vitro. The inhibitory capacity varies depending on the donor and the site of origin of the fibroblast. We showed previously that effective inhibition requires formation of a morphologically intact fibroblast monolayer before seeding of the tumor cells. Here we show that inhibition is extended to motility of tumor cells and we dissect the factors responsible for these inhibitory functions. We find that inhibition is due to two different sets of molecules: (i) the extracellular matrix (ECM) and other surface proteins of the fibroblasts, which are responsible for contact-dependent inhibition of tumor cell proliferation; and (ii) soluble factors secreted by fibroblasts when confronted with tumor cells (confronted conditioned media, CCM) contribute to inhibition of tumor cell proliferation and motility. However, conditioned media (CM) obtained from fibroblasts alone (nonconfronted conditioned media, NCM) did not inhibit tumor cell proliferation and motility. In addition, quantitative PCR (Q-PCR) data show up-regulation of proinflammatory genes. Moreover, comparison of CCM and NCM with an antibody array for 507 different soluble human proteins revealed differential expression of growth differentiation factor 15, dickkopf-related protein 1, endothelial-monocyte-activating polypeptide II, ectodysplasin A2, Galectin-3, chemokine (C-X-C motif) ligand 2, Nidogen1, urokinase, and matrix metalloproteinase 3. PMID:25404301

  6. Aligned Nanotopography Promotes a Migratory State in Glioblastoma Multiforme Tumor Cells

    PubMed Central

    Beliveau, Alexander; Thomas, Gawain; Gong, Jiaxin; Wen, Qi; Jain, Anjana

    2016-01-01

    Glioblastoma multiforme (GBM) is an aggressive, Grade IV astrocytoma with a poor survival rate, primarily due to the GBM tumor cells migrating away from the primary tumor site along the nanotopography of white matter tracts and blood vessels. It is unclear whether this nanotopography influences the biomechanical properties (i.e. cytoskeletal stiffness) of GBM tumor cells. Although GBM tumor cells have an innate propensity to migrate, we believe this capability is enhanced due to the influence of nanotopography on the tumor cells’ biomechanical properties. In this study, we used an aligned nanofiber film that mimics the nanotopography in the tumor microenvironment to investigate the mechanical properties of GBM tumor cells in vitro. The data demonstrate that the cytoskeletal stiffness, cell traction stress, and focal adhesion area were significantly lower in the GBM tumor cells compared to healthy astrocytes. Moreover, the cytoskeletal stiffness was significantly reduced when cultured on aligned nanofiber films compared to smooth and randomly aligned nanofiber films. Gene expression analysis showed that tumor cells cultured on the aligned nanotopography upregulated key migratory genes and downregulated key proliferative genes. Therefore, our data suggest that the migratory potential is elevated when GBM tumor cells are migrating along aligned nanotopographical substrates. PMID:27189099

  7. Structural Features Facilitating Tumor Cell Targeting and Internalization by Bleomycin and Its Disaccharide

    PubMed Central

    2016-01-01

    We have shown previously that the bleomycin (BLM) carbohydrate moiety can recapitulate the tumor cell targeting effects of the entire BLM molecule, that BLM itself is modular in nature consisting of a DNA-cleaving aglycone which is delivered selectively to the interior of tumor cells by its carbohydrate moiety, and that there are disaccharides structurally related to the BLM disaccharide which are more efficient than the natural disaccharide at tumor cell targeting/uptake. Because BLM sugars can deliver molecular cargoes selectively to tumor cells, and thus potentially form the basis for a novel antitumor strategy, it seemed important to consider additional structural features capable of affecting the efficiency of tumor cell recognition and delivery. These included the effects of sugar polyvalency and net charge (at physiological pH) on tumor cell recognition, internalization, and trafficking. Since these parameters have been shown to affect cell surface recognition, internalization, and distribution in other contexts, this study has sought to define the effects of these structural features on tumor cell recognition by bleomycin and its disaccharide. We demonstrate that both can have a significant effect on tumor cell binding/internalization, and present data which suggests that the metal ions normally bound by bleomycin following clinical administration may significantly contribute to the efficiency of tumor cell uptake, in addition to their characterized function in DNA cleavage. A BLM disaccharide-Cy5** conjugate incorporating the positively charged dipeptide d-Lys-d-Lys was found to associate with both the mitochondria and the nuclear envelope of DU145 cells, suggesting possible cellular targets for BLM disaccharide–cytotoxin conjugates. PMID:25905565

  8. Magnetic levitating polymeric nano/microparticular substrates for three-dimensional tumor cell culture.

    PubMed

    Lee, Woong Ryeol; Oh, Kyung Taek; Park, So Young; Yoo, Na Young; Ahn, Yong Sik; Lee, Don Haeng; Youn, Yu Seok; Lee, Deok-Keun; Cha, Kyung-Hoi; Lee, Eun Seong

    2011-07-01

    Herein, we describe magnetic cell levitation models using conventional polymeric microparticles or nanoparticles as a substrate for the three-dimensional tumor cell culture. When the magnetic force originating from the ring-shaped magnets overcame the gravitational force, the magnetic field-levitated KB tumor cells adhered to the surface area of magnetic iron oxide (Fe(3)O(4))-encapsulated nano/microparticles and concentrated clusters of levitated cells, ultimately developing tumor cells to tumor spheroids. These simple cell culture models may prove useful for the screening of anticancer drugs and their formulations. PMID:21420837

  9. Direct visualization of macrophage-assisted tumor cell intravasation in mammary tumors.

    PubMed

    Wyckoff, Jeffrey B; Wang, Yarong; Lin, Elaine Y; Li, Jiu-feng; Goswami, Sumanta; Stanley, E Richard; Segall, Jeffrey E; Pollard, Jeffrey W; Condeelis, John

    2007-03-15

    Although the presence of macrophages in tumors has been correlated with poor prognosis, until now there was no direct observation of how macrophages are involved in hematogenous metastasis. In this study, we use multiphoton microscopy to show, for the first time, that tumor cell intravasation occurs in association with perivascular macrophages in mammary tumors. Furthermore, we show that perivascular macrophages of the mammary tumor are associated with tumor cell intravasation in the absence of local angiogenesis. These results show that the interaction between macrophages and tumor cells lying in close proximity defines a microenvironment that is directly involved in the intravasation of cancer cells in mammary tumors.

  10. Magnetic levitating polymeric nano/microparticular substrates for three-dimensional tumor cell culture.

    PubMed

    Lee, Woong Ryeol; Oh, Kyung Taek; Park, So Young; Yoo, Na Young; Ahn, Yong Sik; Lee, Don Haeng; Youn, Yu Seok; Lee, Deok-Keun; Cha, Kyung-Hoi; Lee, Eun Seong

    2011-07-01

    Herein, we describe magnetic cell levitation models using conventional polymeric microparticles or nanoparticles as a substrate for the three-dimensional tumor cell culture. When the magnetic force originating from the ring-shaped magnets overcame the gravitational force, the magnetic field-levitated KB tumor cells adhered to the surface area of magnetic iron oxide (Fe(3)O(4))-encapsulated nano/microparticles and concentrated clusters of levitated cells, ultimately developing tumor cells to tumor spheroids. These simple cell culture models may prove useful for the screening of anticancer drugs and their formulations.

  11. Gibberellic-acid-induced cell elongation in pea epicotyls: Effect on polyploidy and DNA content.

    PubMed

    Boeken, G; Van Oostveldt, P

    1977-01-01

    In gibberellic-acid(GA3)-treated epicotyls of dwarf peas (Pisum sativum L.) grown in the light, DNA (per cell and per epicotyl) is followed. Histofluorometric DNA determinations show that GA3-promoted cell elongation is not accompanied by increased endomitosis, but chemical estimations show an increased DNA content per epicotyl. This difference must therefore be the result of increased mitotic activity in the GA3-treated tissue. Epicotyls of seedlings grown with or without cotyledons under continuous light with GA3 are tetraploid, as are those of ecotylized embryos grown in darkness. These epicotyls reach no more than half the length of octaploid epicotyls of seedlings grown in darkness. This result provides evidence for a relationship between polyploidy and final possible cell length. PMID:24419898

  12. The microRNA-200/Zeb1 axis regulates ECM-dependent β1-integrin/FAK signaling, cancer cell invasion and metastasis through CRKL

    PubMed Central

    Ungewiss, Christin; Rizvi, Zain H.; Roybal, Jonathon D.; Peng, David H.; Gold, Kathryn A.; Shin, Dong-Hoon; Creighton, Chad J.; Gibbons, Don L.

    2016-01-01

    Tumor cell metastasis is a complex process that has been mechanistically linked to the epithelial-mesenchymal transition (EMT). The double-negative feedback loop between the microRNA-200 family and the Zeb1 transcriptional repressor is a master EMT regulator, but there is incomplete understanding of how miR-200 suppresses invasion. Our recent efforts have focused on the tumor cell-matrix interactions essential to tumor cell activation. Herein we utilized both our Kras/p53 mutant mouse model and human lung cancer cell lines to demonstrate that upon miR-200 loss integrin β1-collagen I interactions drive 3D in vitro migration/invasion and in vivo metastases. Zeb1-dependent EMT enhances tumor cell responsiveness to the ECM composition and activates FAK/Src pathway signaling by de-repression of the direct miR-200 target, CRKL. We demonstrate that CRKL serves as an adaptor molecule to facilitate focal adhesion formation, mediates outside-in signaling through Itgβ1 to drive cell invasion, and inside-out signaling that maintains tumor cell-matrix contacts required for cell invasion. Importantly, CRKL levels in pan-cancer TCGA analyses were predictive of survival and CRKL knockdown suppressed experimental metastases in vivo without affecting primary tumor growth. Our findings highlight the critical ECM-tumor cell interactions regulated by miR-200/Zeb1-dependent EMT that activate intracellular signaling pathways responsible for tumor cell invasion and metastasis. PMID:26728244

  13. The microRNA-200/Zeb1 axis regulates ECM-dependent β1-integrin/FAK signaling, cancer cell invasion and metastasis through CRKL.

    PubMed

    Ungewiss, Christin; Rizvi, Zain H; Roybal, Jonathon D; Peng, David H; Gold, Kathryn A; Shin, Dong-Hoon; Creighton, Chad J; Gibbons, Don L

    2016-01-01

    Tumor cell metastasis is a complex process that has been mechanistically linked to the epithelial-mesenchymal transition (EMT). The double-negative feedback loop between the microRNA-200 family and the Zeb1 transcriptional repressor is a master EMT regulator, but there is incomplete understanding of how miR-200 suppresses invasion. Our recent efforts have focused on the tumor cell-matrix interactions essential to tumor cell activation. Herein we utilized both our Kras/p53 mutant mouse model and human lung cancer cell lines to demonstrate that upon miR-200 loss integrin β1-collagen I interactions drive 3D in vitro migration/invasion and in vivo metastases. Zeb1-dependent EMT enhances tumor cell responsiveness to the ECM composition and activates FAK/Src pathway signaling by de-repression of the direct miR-200 target, CRKL. We demonstrate that CRKL serves as an adaptor molecule to facilitate focal adhesion formation, mediates outside-in signaling through Itgβ1 to drive cell invasion, and inside-out signaling that maintains tumor cell-matrix contacts required for cell invasion. Importantly, CRKL levels in pan-cancer TCGA analyses were predictive of survival and CRKL knockdown suppressed experimental metastases in vivo without affecting primary tumor growth. Our findings highlight the critical ECM-tumor cell interactions regulated by miR-200/Zeb1-dependent EMT that activate intracellular signaling pathways responsible for tumor cell invasion and metastasis. PMID:26728244

  14. A new role for GABA: inhibition of tumor cell migration.

    PubMed

    Ortega, Arturo

    2003-04-01

    GABA, the main inhibitory neurotransmitter in the vertebrate brain, participates outside the CNS in diverse functions such as platelet aggregation and the acrosomal reaction in spermatozoa. A recent study now demonstrates that GABA inhibits the migration of colon carcinoma cells, paving the way to the development of specific pharmacological agents that delay or inhibit invasion and metastasis of various cancer types.

  15. Rapid reuptake of granzyme B leads to emperitosis: an apoptotic cell-in-cell death of immune killer cells inside tumor cells.

    PubMed

    Wang, S; He, M-f; Chen, Y-h; Wang, M-y; Yu, X-M; Bai, J; Zhu, H-y; Wang, Y-y; Zhao, H; Mei, Q; Nie, J; Ma, J; Wang, J-f; Wen, Q; Ma, L; Wang, Y; Wang, X-n

    2013-01-01

    A cell-in-cell process refers to the invasion of one living cell into another homotypic or heterotypic cell. Different from non-apoptotic death processes of internalized cells termed entosis or cannibalism, we previously reported an apoptotic cell-in-cell death occurring during heterotypic cell-in-cell formation. In this study, we further demonstrated that the apoptotic cell-in-cell death occurred only in internalized immune killer cells expressing granzyme B (GzmB). Vacuole wrapping around the internalized cells inside the target cells was the common hallmark during the early stage of all cell-in-cell processes, which resulted in the accumulation of reactive oxygen species and subsequent mitochondrial injury of encapsulated killer or non-cytotoxic immune cells. However, internalized killer cells mediated rapid bubbling of the vacuoles with the subsequent degranulation of GzmB inside the vacuole of the target cells and underwent the reuptake of GzmB by killer cells themselves. The confinement of GzmB inside the vacuole surpassed the lysosome-mediated cell death occurring in heterotypic or homotypic entosis processes, resulting in a GzmB-triggered caspase-dependent apoptotic cell-in-cell death of internalized killer cells. On the contrary, internalized killer cells from GzmB-deficient mice underwent a typical non-apoptotic entotic cell-in-cell death similar to that of non-cytotoxic immune cells or tumor cells. Our results thus demonstrated the critical involvement of immune cells with cytotoxic property in apoptotic cell-in-cell death, which we termed as emperitosis taken from emperipolesis and apoptosis. Whereas entosis or cannibalism may serve as a feed-on mechanism to exacerbate and nourish tumor cells, emperitosis of immune killer cells inside tumor cells may serve as an in-cell danger sensation model to prevent the killing of target cells from inside, implying a unique mechanism for tumor cells to escape from immune surveillance. PMID:24113190

  16. Detection of live circulating tumor cells by a class of near-infrared heptamethine carbocyanine dyes in patients with localized and metastatic prostate cancer.

    PubMed

    Shao, Chen; Liao, Chun-Peng; Hu, Peizhen; Chu, Chia-Yi; Zhang, Lei; Bui, Matthew H T; Ng, Christopher S; Josephson, David Y; Knudsen, Beatrice; Tighiouart, Mourad; Kim, Hyung L; Zhau, Haiyen E; Chung, Leland W K; Wang, Ruoxiang; Posadas, Edwin M

    2014-01-01

    Tumor cells are inherently heterogeneous and often exhibit diminished adhesion, resulting in the shedding of tumor cells into the circulation to form circulating tumor cells (CTCs). A fraction of these are live CTCs with potential of metastatic colonization whereas others are at various stages of apoptosis making them likely to be less relevant to understanding the disease. Isolation and characterization of live CTCs may augment information yielded by standard enumeration to help physicians to more accurately establish diagnosis, choose therapy, monitor response, and provide prognosis. We previously reported on a group of near-infrared (NIR) heptamethine carbocyanine dyes that are specifically and actively transported into live cancer cells. In this study, this viable tumor cell-specific behavior was utilized to detect live CTCs in prostate cancer patients. Peripheral blood mononuclear cells (PBMCs) from 40 patients with localized prostate cancer together with 5 patients with metastatic disease were stained with IR-783, the prototype heptamethine cyanine dye. Stained cells were subjected to flow cytometric analysis to identify live (NIR(+)) CTCs from the pool of total CTCs, which were identified by EpCAM staining. In patients with localized tumor, live CTC counts corresponded with total CTC numbers. Higher live CTC counts were seen in patients with larger tumors and those with more aggressive pathologic features including positive margins and/or lymph node invasion. Even higher CTC numbers (live and total) were detected in patients with metastatic disease. Live CTC counts declined when patients were receiving effective treatments, and conversely the counts tended to rise at the time of disease progression. Our study demonstrates the feasibility of applying of this staining technique to identify live CTCs, creating an opportunity for further molecular interrogation of a more biologically relevant CTC population. PMID:24551200

  17. Detection of live circulating tumor cells by a class of near-infrared heptamethine carbocyanine dyes in patients with localized and metastatic prostate cancer.

    PubMed

    Shao, Chen; Liao, Chun-Peng; Hu, Peizhen; Chu, Chia-Yi; Zhang, Lei; Bui, Matthew H T; Ng, Christopher S; Josephson, David Y; Knudsen, Beatrice; Tighiouart, Mourad; Kim, Hyung L; Zhau, Haiyen E; Chung, Leland W K; Wang, Ruoxiang; Posadas, Edwin M

    2014-01-01

    Tumor cells are inherently heterogeneous and often exhibit diminished adhesion, resulting in the shedding of tumor cells into the circulation to form circulating tumor cells (CTCs). A fraction of these are live CTCs with potential of metastatic colonization whereas others are at various stages of apoptosis making them likely to be less relevant to understanding the disease. Isolation and characterization of live CTCs may augment information yielded by standard enumeration to help physicians to more accurately establish diagnosis, choose therapy, monitor response, and provide prognosis. We previously reported on a group of near-infrared (NIR) heptamethine carbocyanine dyes that are specifically and actively transported into live cancer cells. In this study, this viable tumor cell-specific behavior was utilized to detect live CTCs in prostate cancer patients. Peripheral blood mononuclear cells (PBMCs) from 40 patients with localized prostate cancer together with 5 patients with metastatic disease were stained with IR-783, the prototype heptamethine cyanine dye. Stained cells were subjected to flow cytometric analysis to identify live (NIR(+)) CTCs from the pool of total CTCs, which were identified by EpCAM staining. In patients with localized tumor, live CTC counts corresponded with total CTC numbers. Higher live CTC counts were seen in patients with larger tumors and those with more aggressive pathologic features including positive margins and/or lymph node invasion. Even higher CTC numbers (live and total) were detected in patients with metastatic disease. Live CTC counts declined when patients were receiving effective treatments, and conversely the counts tended to rise at the time of disease progression. Our study demonstrates the feasibility of applying of this staining technique to identify live CTCs, creating an opportunity for further molecular interrogation of a more biologically relevant CTC population.

  18. Pollen and stomata morphometrics and polyploidy in Eriotheca (Malvaceae-Bombacoideae).

    PubMed

    Marinho, R C; Mendes-Rodrigues, C; Bonetti, A M; Oliveira, P E

    2014-03-01

    Approximately 70% of the angiosperm species are polyploid, an important phenomenon in the evolution of those plants. But ploidy estimates have often been hindered because of the small size and large number of chromosomes in many tropical groups. Since polyploidy affects cell size, morphometric analyses of pollen grains and stomata have been used to infer ploidy level. Polyploidy is present in many species of the Cerrado, the Neotropical savanna region in Central Brazil, and has been linked to apomixis in some taxa. Eriotheca gracilipes and Eriotheca pubescens are common tree species in this region, and present cytotypes that form reproductive mosaics. Hexaploid individuals (2n = 6x = 276) are polyembryonic and apomictic, while tetraploid and diploid individuals (2n = 2x = 92, 2n = 4x = 184) are sexual and monoembryonic. We tested whether morphometric analysis can be used to estimate ploidy levels in E. gracilipes and E. pubescens individuals. Pollen material from diploid and hexaploid individuals of E. gracilipes, and tetraploid and hexaploid individuals of E. pubescens, were fixed in 50% FAA, and expanded leaves were dried in silica gel. Pollen grains and stomata of at least five individuals from each population were measured. The results demonstrate that all measures were significantly different among cytotypes. Individuals with higher levels of ploidy (hexaploid) all presented measurements that were higher than those with lower levels (diploid and tetraploid). There was no overlap between ploidy levels in each species at 95% confidence interval. Thus, the size of the pollen grains and stomata are effective parameters for analysis of ploidy levels in E. gracilipes and E. pubescens.

  19. Pollen and stomata morphometrics and polyploidy in Eriotheca (Malvaceae-Bombacoideae).

    PubMed

    Marinho, R C; Mendes-Rodrigues, C; Bonetti, A M; Oliveira, P E

    2014-03-01

    Approximately 70% of the angiosperm species are polyploid, an important phenomenon in the evolution of those plants. But ploidy estimates have often been hindered because of the small size and large number of chromosomes in many tropical groups. Since polyploidy affects cell size, morphometric analyses of pollen grains and stomata have been used to infer ploidy level. Polyploidy is present in many species of the Cerrado, the Neotropical savanna region in Central Brazil, and has been linked to apomixis in some taxa. Eriotheca gracilipes and Eriotheca pubescens are common tree species in this region, and present cytotypes that form reproductive mosaics. Hexaploid individuals (2n = 6x = 276) are polyembryonic and apomictic, while tetraploid and diploid individuals (2n = 2x = 92, 2n = 4x = 184) are sexual and monoembryonic. We tested whether morphometric analysis can be used to estimate ploidy levels in E. gracilipes and E. pubescens individuals. Pollen material from diploid and hexaploid individuals of E. gracilipes, and tetraploid and hexaploid individuals of E. pubescens, were fixed in 50% FAA, and expanded leaves were dried in silica gel. Pollen grains and stomata of at least five individuals from each population were measured. The results demonstrate that all measures were significantly different among cytotypes. Individuals with higher levels of ploidy (hexaploid) all presented measurements that were higher than those with lower levels (diploid and tetraploid). There was no overlap between ploidy levels in each species at 95% confidence interval. Thus, the size of the pollen grains and stomata are effective parameters for analysis of ploidy levels in E. gracilipes and E. pubescens. PMID:24341784

  20. Instant magnetic labeling of tumor cells by ultrasound in vitro

    NASA Astrophysics Data System (ADS)

    Mo, Runyang; Yang, Jian; Wu, Ed X.; Lin, Shuyu

    2011-09-01

    Magnetic labeling of living cells creates opportunities for numerous biomedical applications. Here we describe an instantly cell magnetic labeling method based on ultrasound. We present a detailed study on the ultrasound performance of a simple and efficient labeling protocol for H-22 cells in vitro. High frequency focus ultrasound was investigated as an alternative method to achieve instant cell labeling with the magnetic particles without the need for adjunct agents or initiating cell cultures. Mean diameter of 168 nm dextran-T40 coated superparamagnetic iron oxide (SPIO) nanoparticles were prepared by means of classical coprecipitation in solution in our laboratory. H-22 tumor cells suspended in phosphate-buffered saline (PBS, pH=7.2) were exposed to ultrasound at 1.37 MHz for up to 120 s in the presence of SPIOs. The cellular uptake of iron oxide nanoparticles was detected by prussion blue staining. The viability of cells was determined by a trypan blue exclusion test. At 2 W power and 60 s ultrasound exposure in presence of 410 μg/ml SPIOs, H-22 cell labeling efficiency reached 69.4±6.3% and the labeled cells exhibited an iron content of 10.38±2.43 pg per cell. Furthermore, 95.2±3.2% cells remained viable. The results indicated that the ultrasound protocol could be potentially applied to label cells with large-sized magnetic particles. We also calculated the shear stress at the 2 W power and 1.37 MHz used in experiments. The results showed that the shear stress threshold for ultrasonically induced H-22 cell reparable sonoporation was 697 Pa. These findings provide a quantitative guidance in designing ultrasound protocols for cell labeling.

  1. Morphological effect of oscillating magnetic nanoparticles in killing tumor cells

    PubMed Central

    2014-01-01

    Forced oscillation of spherical and rod-shaped iron oxide magnetic nanoparticles (MNPs) via low-power and low-frequency alternating magnetic field (AMF) was firstly used to kill cancer cells in vitro. After being loaded by human cervical cancer cells line (HeLa) and then exposed to a 35-kHz AMF, MNPs mechanically damaged cell membranes and cytoplasm, decreasing the cell viability. It was found that the concentration and morphology of the MNPs significantly influenced the cell-killing efficiency of oscillating MNPs. In this preliminary study, when HeLa cells were pre-incubated with 100 μg/mL rod-shaped MNPs (rMNP, length of 200 ± 50 nm and diameter of 50 to 120 nm) for 20 h, MTT assay proved that the cell viability decreased by 30.9% after being exposed to AMF for 2 h, while the cell viability decreased by 11.7% if spherical MNPs (sMNP, diameter of 200 ± 50 nm) were used for investigation. Furthermore, the morphological effect of MNPs on cell viability was confirmed by trypan blue assay: 39.5% rMNP-loaded cells and 15.1% sMNP-loaded cells were stained after being exposed to AMF for 2 h. It was also interesting to find that killing tumor cells at either higher (500 μg/mL) or lower (20 μg/mL) concentration of MNPs was less efficient than that achieved at 100 μg/mL concentration. In conclusion, the relatively asymmetric morphological rod-shaped MNPs can kill cancer cells more effectively than spherical MNPs when being exposed to AMF by virtue of their mechanical oscillations. PMID:24872797

  2. Analysis of circulating tumor cells derived from advanced gastric cancer.

    PubMed

    Toyoshima, Kosei; Hayashi, Akira; Kashiwagi, Masahide; Hayashi, Naoko; Iwatsuki, Masaaki; Ishimoto, Takatsugu; Baba, Yoshifumi; Baba, Hideo; Ohta, Yoshikazu

    2015-08-15

    Studies in circulating tumor cells (CTCs) have proceeded to be accepted as prognostic markers in several types of cancers. But they are still limited because many are mainly from enumeration of CTCs. Here, we tried to evaluate the tumorigenicity of CTCs from advanced gastric cancer patients (n = 42). Peripheral blood mononuclear cells (PBMC) from the patients were separated into CD45 negative and positive fractions and both were subcutaneously injected into immunodeficient mice. Within 5 months nine tumor-like-structures from six patients but not from healthy volunteers were established. They were durable for passages and all had been confirmed human origin. Eight of the nine tumor-like-structures were from nonauthorized CTC containing cells expressing CD45 and B-cell markers. On the contrary, one of them was developed from CD45(-) PBMC fraction of a patient with bone marrow metastasis reflecting authorized CTCs. Histopathology showed common features with that of original gastric tumor. The cells isolated from the tumor-like-structure expressed EpCAM and CEA further supporting they were from the original tumor. Moreover the cells were CD44 positive to varying degree and a limiting dilution study showed that the CD44(+/high) fraction had tumorigenicity. The CD44 was dominantly in the form of CD44 variant 8-10. The CD44(+/high) cells had higher expression of the glutamate/cysteine transporter xCT compared with the CD44(-/low) cells. Our results showed the existence of tumor-initiating cells in blood of advanced gastric cancer patients and they could be a therapeutic target and prospective tool for further investigations.

  3. Lab-on-chip platform for circulating tumor cells isolation

    NASA Astrophysics Data System (ADS)

    Maurya, D. K.; Fooladvand, M.; Gray, E.; Ziman, M.; Alameh, K.

    2015-12-01

    We design, develop and demonstrate the principle of a continuous, non-intrusive, low power microfluidics-based lab-ona- chip (LOC) structure for Circulating Tumor Cell (CTC) separation. Cell separation is achieved through 80 cascaded contraction and expansion microchannels of widths 60 μm and 300 μm, respectively, and depth 60 μm, which enable momentum-change-induced inertial forces to be exerted on the cells, thus routing them to desired destinations. The total length of the developed LOC is 72 mm. The LOC structure is simulated using the COMSOL multiphysics software, which enables the optimization of the dimensions of the various components of the LOC structure, namely the three inlets, three filters, three contraction and expansion microchannel segments and five outlets. Simulation results show that the LOC can isolate CTCs of sizes ranging from 15 to 30 μm with a recovery rate in excess of 90%. Fluorescent microparticles of two different sizes (5 μm and 15 μm), emulating blood and CTC cells, respectively, are used to demonstrate the principle of the developed LOC. A mixture of these microparticles is injected into the primary LOC inlet via an electronically-controlled syringe pump, and the large-size particles are routed to the primary LOC outlet through the contraction and expansion microchannels. Experimental results demonstrate the ability of the developed LOC to isolate particles by size exclusion with an accuracy of 80%. Ongoing research is focusing on the LOC design improvement for better separation efficiency and testing of biological samples for isolation of CTCs.

  4. Circulating tumors cells as biomarkers: progress toward biomarker qualification.

    PubMed

    Danila, Daniel C; Pantel, Klaus; Fleisher, Martin; Scher, Howard I

    2011-01-01

    Personalized cancer medicine requires the development of tumor-specific biomarkers to optimize selection of targeted therapies and to better assess response to therapy. Current efforts in several tumor types have shown that patients in whom circulating tumor cells (CTCs) are detected have an inferior prognosis relative to those in whom CTCs are not detected and that the elimination or decrease of CTCs following treatment is associated with improved clinical outcomes. Technological advances in the detection, isolation, capture, and characterization of CTCs from phlebotomy samples obtained in a routine clinical practice setting have enabled the evaluation of different CTC biomarkers. Unmet needs in cancer diagnosis and treatment where CTC biomarkers have been studied include determining prognosis, assessing the effects of treatment, and as a source of tumor for the biologic identification and characterization of determinants to predict sensitivity to one form of treatment versus another and to understand mechanisms of treatment resistance.At present, there is no single definition of a CTC and no single CTC "biomarker." Rather, multiple assays (tests) are in development for CTC biomarkers. However, before the role of any biomarker in medical decision making can be determined, it is essential that the assays used to measure the biomarker are analytically validated in a sequence of trials to generate the evidence to support the biomarker's use in the given context of use. It is against this background that this review focuses on the process of developing CTC biomarker assays, with the objective of outlining the necessary steps to qualify specific CTC tests for medical decision making in clinical practice or drug development. The potential for point-of-care tests is clear.

  5. Micro FT-IR Characterization Of Human Lung Tumor Cells

    NASA Astrophysics Data System (ADS)

    Benedetti, Enzo; Teodori, L.; Vergamini, Piergiorgio; Trinca, M. L.; Mauro, F.; Salvati, F.; Spremolla, Giuliano

    1989-12-01

    FT-IR spectroscopy has opened up a new approach to the analytical study of cell transformation. Investigations carried out in normal and leukemic lymphocytes have evidenced an increase in DNA with respect to proteic components in neoplastic cells.(1) The evaluation of the ratio of the integrated areas(A) of the bands at 1080 cm-1 (mainly DNA) and at 1540 cm-1 (proteic components) has allowed us to establish a parameter which indicates, for values above 1.5, the neoplastic nature of cells. Recently, this approach has been applied to the study of human lung tumor cells. Several monocellular suspension procedures of the tissue fragment (mechanical and/or chemical) were tested to obtain reproducible and reliable spectra able to differentiate clearly between normal and patological cells. Chemical treatment (EDTA, Pepsin, Collagenase, etc.) produced additional bands in the spectra of the cells causing distortion of the profiles of some absorptions, and as a result, mechanical treatment was preferred. The normal and neoplastic cells homogeneously distributed by cytospin preparation on BaF2 windows were examined by means of FT-IR microscopy. An examination of several microareas of each sample yielded reproducible spectra, with values of the A 1080 cm-1 / A 1540 cm-1 parameter within a very narrow range for each sample, even if certain differences still remained among the different cases, in good agreement with the results obtained for leukemic cells.(1) The value of this parameter was found to be lower for cells isolated from the normal area of lung, than in the case of those corresponding to the tumoral area, meaning that an increase occurs in DNA with respect to the proteic components. These insights, which provide a basis to obtain indications at the molecular level, can open up new possibilities in clinical practice, in order to obtain diagnosis confirmation, to detect early stages of disease and to offer additional indications in cases of dubious interpretation.

  6. Biomarker utility of circulating tumor cells in metastatic cutaneous melanoma.

    PubMed

    Khoja, Leila; Lorigan, Paul; Zhou, Cong; Lancashire, Matthew; Booth, Jessica; Cummings, Jeff; Califano, Raffaele; Clack, Glen; Hughes, Andrew; Dive, Caroline

    2013-06-01

    The incidence of melanoma is increasing worldwide. Advances in targeted agents and immunotherapy have improved outcomes in metastatic disease, but biomarkers are required to optimize treatment. We determined the prevalence of circulating tumor cells (CTCs) and explored their utility as prognostic and pharmacodynamic biomarkers. A total of 101 patients with metastatic cutaneous melanoma were recruited prospectively. CTC number was determined using the CellSearch platform and melanoma kits in samples taken at baseline and serially during treatment. CTC numbers ranged between 0 and 36 per 7.5 ml blood; 26% of patients had ≥ 2 CTCs. Baseline CTC number was prognostic for median overall survival (OS) in univariate analysis (2.6 vs. 7.2 months (P<0.011) for patients with ≥ 2 CTCs vs. <2 CTCs, respectively). In multivariate analysis, CTC number was an independent prognostic biomarker of OS (hazard ratio (HR) 2.403, 95% confidence interval (CI) 1.303-4.430, P=0.005). Patients receiving treatment in whom CTC number remained ≥ 2 CTCs during treatment had shorter median OS than those who maintained <2 CTCs (7 vs. 10 months, HR 0.34, 95% CI 0.14-0.81, log-rank test P=0.015). In conclusion, CTC number in metastatic cutaneous melanoma patients is prognostic for OS with a cutoff of 2 CTCs per 7.5 ml blood. CTC number measured before and throughout treatment provided additional prognostic information. Larger studies are warranted to confirm CTC biomarker utility in melanoma patients. PMID:23223143

  7. Automated identification of circulating tumor cells by image cytometry.

    PubMed

    Scholtens, Tycho M; Schreuder, Frederik; Ligthart, Sjoerd T; Swennenhuis, Joost F; Greve, Jan; Terstappen, Leon W M M

    2012-02-01

    Presence of circulating tumor cells (CTC), as detected by the CellSearch System, in patients with metastatic carcinomas is associated with poor survival prospects. CellTracks TDI, a dedicated image cytometer, was developed to improve the enumeration of these rare CTC. The CellSearch System was used to enumerate CTC in 7.5 mL blood of 68 patients with cancer and 9 healthy controls. Cartridges containing the fluorescently labeled CTC from this system were reanalyzed using the image cytometer, which acquires images with a TDI camera using a 40×/0.6 NA objective and lasers as light source. Automated classification of events was performed by the Random Forest method using Matlab. An automated classifier was developed to classify events into CTC, apoptotic CTC, CTC debris, leukocytes, and debris not related to CTC. A high agreement in classification was obtained between the automated classifier and five expert reviewers. Comparison of images from the same events in CellTracks TDI and CellTracks Analyzer II shows improved resolution in fluorescence images and improved classification by adding bright-field images. Improved detection efficiency for CD45-APC avoids the classification of leukocytes nonspecifically binding to cytokeratin as CTC. The correlation between number of CTC detected in CellTracks TDI and CellTracks Analyzer II is good with a slope of 1.88 and a correlation coefficient of 0.87. Automated classification of events by CellTracks TDI eliminates the operator error in classification of events as CTC and permits quantitative assessment of parameters. The clinical relevance of various CTC definitions can now be investigated.

  8. Importance of circulating tumor cells in newly diagnosed colorectal cancer.

    PubMed

    van Dalum, Guus; Stam, Gerrit-Jan; Scholten, Loes F A; Mastboom, Walter J B; Vermes, Istvan; Tibbe, Arjan G J; De Groot, Marco R; Terstappen, Leon W M M

    2015-03-01

    Presence of circulating tumor cells (CTC) is associated with poor prognosis in patients with metastatic colorectal cancer (CRC). The present study was conducted to determine if the presence of CTC prior to surgery and during follow‑up in patients with newly diagnosed non-metastatic CRC can identify patients at risk for disease recurrence. In a prospective single center study 183 patients with newly diagnosed non-disseminated CRC, scheduled for surgery, were enrolled and followed-up for a median of 5.1 years. CTC were enumerated with the CellSearch system in 4 aliquots of 7.5 ml of blood before surgery and at several time-points during follow-up after surgery. The results showed that ≥1 CTC/30 ml of blood were detected in 44 (24%) patients before surgery. Patients with CTC before surgery had a significant decrease in recurrence-free survival (RFS, log-rank test p=0.014) and colon cancer related survival (CCRS, p=0.002). The 5-year RFS dropped from 75 to 61% and the 5-year CCRS from 83 to 69% for patients with CTC before surgery. The presence of CTC and positive lymph nodes remained significant factors in multivariate analysis for recurrence-free survival (RFS). Surprisingly, the presence of CTC weeks after surgery was not significantly associated with RFS and CCRD whereas CTC 2-3 years after surgery was again significantly associated with RFS and CCRD. The presence of CTC in patients with stage I-III CRC before surgery is associated with a significant reduction in RFS and CCRS. These findings suggest a role of CTC detection to assess which patients need adjuvant treatment.

  9. Inhibitory effect of delphinidin from Solanum melongena on human fibrosarcoma HT-1080 invasiveness in vitro.

    PubMed

    Nagase, H; Sasaki, K; Kito, H; Haga, A; Sato, T

    1998-04-01

    We investigated the inhibitory effect of eggplant (Solanum melongena var. marunasu) extract on human fibrosarcoma HT-1080 cell invasion of reconstituted basement membrane [Matrigel (MG)]. We found that the effective component of the plant extract was delphinidin, a flavonoid pigment contained in the peel. The extract and delphinidin did not affect tumor cell adhesion to MG or haptotactic migration to MG. HT-1080 secretes matrix metalloproteinase(MMP)-2 and MMP-9, which degrade extracellular matrix as part of the invasive process. Delphinidin slightly inhibited the activity of MMPs, which may have been responsible, in part, for the inhibition of tumor cell invasiveness. PMID:9581517

  10. Effect of immunomodulation on the fate of tumor cells in the central nervous system and systemic organs of mice. Distribution of (/sup 125/I)5-iodo-2'-deoxyuridine-labeled KHT tumor cells after left intracardial injection

    SciTech Connect

    Conley, F.K.

    1982-08-01

    The effect of systemic immunomodulation on tumor cell arrest and retention in the central nervous system was studied by following radioactively labeled tumor cells. KHT mouse sarcoma tumor cells were labeled in vitro with (/sup 125/I)IdUrd, and 1x10/sup 5/ tumor cells were injected into the left side of the hearts of syngeneic C3H mice. Experimental groups consisted of untreated normal mice, mice pretreated iv with Corynebacterium parvum, and mice chronically infected with Toxoplasma gondii; in this model both groups of immunomodulated mice are protected from developing systemic metastatic tumor, but only Toxoplasma-infected mice have protection against metastatic brain tumor. At time intervals from 1 to 96 hours, groups of mice from each experimental group were killed, and the brain and other organs were monitored for radioactivity to determine the number of viable tumor cells that had been present at the time of death. Normal mice demonstrated significant retention of tumor cells in the brain and kidneys plus adrenals at 96 hours. By contrast, in both groups of immunomodulated mice tumor cells were rapidly eliminated from systemic organs, but tumor cells were significantly retained in the central nervous system even at 96 hours after tumor cell injections. The results indicated that generalized immunomodulation had more effect in elimination of tumor cells from systemic organs than from the brain and that the elimination of tumor cells from the brain in Toxoplasma-infected mice was a delayed phenomenon.

  11. Over-expression of tetraspanin 8 in malignant glioma regulates tumor cell progression

    SciTech Connect

    Pan, Si-Jian; Wu, Yue-Bing; Cai, Shang; Pan, Yi-Xin; Liu, Wei; Bian, Liu-Guan; Sun, Bomin; Sun, Qing-Fang

    2015-03-13

    Tumor cell invasion and proliferation remain the overwhelming causes of death for malignant glioma patients. To establish effective therapeutic methods, new targets implied in these processes have to be identified. Tetraspanin 8 (Tspn8) forms complexes with a large variety of trans-membrane and/or cytosolic proteins to regulate several important cellular functions. In the current study, we found that Tspn8 was over-expressed in multiple clinical malignant glioma tissues, and its expression level correlated with the grade of tumors. Tspn8 expression in malignant glioma cells (U251MG and U87MG lines) is important for cell proliferation and migration. siRNA-mediated knockdown of Tspn8 markedly reduced in vitro proliferation and migration of U251MG and U87MG cells. Meanwhile, Tspn8 silencing also increased the sensitivity of temozolomide (TMZ), and significantly increased U251MG or U87MG cell death and apoptosis by TMZ were achieved with Tspn8 knockdown. We observed that Tspn8 formed a complex with activated focal adhesion kinase (FAK) in both human malignant glioma tissues and in above glioma cells. This complexation appeared required for FAK activation, since Tspn8 knockdown inhibited FAK activation in U251MG and U87MG cells. These results provide evidence that Tspn8 contributes to the pathogenesis of glioblastoma probably by promoting proliferation, migration and TMZ-resistance of glioma cells. Therefore, targeting Tspn8 may provide a potential therapeutic intervention for malignant glioma. - Highlights: • Tspn8 is over-expressed in multiple clinical malignant glioma tissues. • Tspn8 expression is correlated with the grade of malignant gliomas. • Tspn8 knockdown suppresses U251MG/U87MG proliferation and in vitro migration. • Tspn8 knockdown significantly increases TMZ sensitivity in U251MG/U87MG cells. • Tspn8 forms a complex with FAK, required for FAK activation.

  12. Classification of large circulating tumor cells isolated with ultra-high throughput microfluidic Vortex technology

    PubMed Central

    Che, James; Yu, Victor; Dhar, Manjima; Renier, Corinne; Matsumoto, Melissa; Heirich, Kyra; Garon, Edward B.; Goldman, Jonathan; Rao, Jianyu; Sledge, George W.; Pegram, Mark D.; Sheth, Shruti; Jeffrey, Stefanie S.; Kulkarni, Rajan P.; Sollier, Elodie; Di Carlo, Dino

    2016-01-01

    Circulating tumor cells (CTCs) are emerging as rare but clinically significant non-invasive cellular biomarkers for cancer patient prognosis, treatment selection, and treatment monitoring. Current CTC isolation approaches, such as immunoaffinity, filtration, or size-based techniques, are often limited by throughput, purity, large output volumes, or inability to obtain viable cells for downstream analysis. For all technologies, traditional immunofluorescent staining alone has been employed to distinguish and confirm the presence of isolated CTCs among contaminating blood cells, although cells isolated by size may express vastly different phenotypes. Consequently, CTC definitions have been non-trivial, researcher-dependent, and evolving. Here we describe a complete set of objective criteria, leveraging well-established cytomorphological features of malignancy, by which we identify large CTCs. We apply the criteria to CTCs enriched from stage IV lung and breast cancer patient blood samples using the High Throughput Vortex Chip (Vortex HT), an improved microfluidic technology for the label-free, size-based enrichment and concentration of rare cells. We achieve improved capture efficiency (up to 83%), high speed of processing (8 mL/min of 10x diluted blood, or 800 μL/min of whole blood), and high purity (avg. background of 28.8±23.6 white blood cells per mL of whole blood). We show markedly improved performance of CTC capture (84% positive test rate) in comparison to previous Vortex designs and the current FDA-approved gold standard CellSearch assay. The results demonstrate the ability to quickly collect viable and pure populations of abnormal large circulating cells unbiased by molecular characteristics, which helps uncover further heterogeneity in these cells. PMID:26863573

  13. The significance of circulating tumor cells in prostate cancer patients undergoing adjuvant or salvage radiation therapy

    PubMed Central

    Lowes, L E; Lock, M; Rodrigues, G; D'Souza, D; Bauman, G; Ahmad, B; Venkatesan, V; Allan, A L; Sexton, T

    2015-01-01

    Background: Following radical prostatectomy, success of adjuvant and salvage radiation therapy (RT) is dependent on the absence of micrometastatic disease. However, reliable prognostic/predictive factors for determining this are lacking. Therefore, novel biomarkers are needed to assist with clinical decision-making in this setting. Enumeration of circulating tumor cells (CTCs) using the regulatory-approved CellSearch System (CSS) is prognostic in metastatic prostate cancer. We hypothesize that CTCs may also be prognostic in the post-prostatectomy setting. Methods: Patient blood samples (n=55) were processed on the CSS to enumerate CTCs at 0, 6, 12 and 24 months after completion of RT. CTC values were correlated with predictive/prognostic factors and progression-free survival. Results: CTC status (presence/absence) correlated significantly with positive margins (increased likelihood of CTCneg disease; P=0.032), and trended toward significance with the presence of seminal vesicle invasion (CTCpos; P=0.113) and extracapsular extension (CTCneg; P=0.116). Although there was a trend toward a decreased time to biochemical failure (BCF) in baseline CTC-positive patients (n=9), this trend was not significant (hazard ratio (HR)=0.3505; P=0.166). However, CTC-positive status at any point (n=16) predicted for time to BCF (HR=0.2868; P=0.0437). Conclusions: One caveat of this study is the small sample size utilized (n=55) and the low number of patients with CTC-positive disease (n=16). However, our results suggest that CTCs may be indicative of disseminated disease and assessment of CTCs during RT may be helpful in clinical decision-making to determine, which patients may benefit from RT versus those who may benefit more from systemic treatments. PMID:26238233

  14. Classification of large circulating tumor cells isolated with ultra-high throughput microfluidic Vortex technology.

    PubMed

    Che, James; Yu, Victor; Dhar, Manjima; Renier, Corinne; Matsumoto, Melissa; Heirich, Kyra; Garon, Edward B; Goldman, Jonathan; Rao, Jianyu; Sledge, George W; Pegram, Mark D; Sheth, Shruti; Jeffrey, Stefanie S; Kulkarni, Rajan P; Sollier, Elodie; Di Carlo, Dino

    2016-03-15

    Circulating tumor cells (CTCs) are emerging as rare but clinically significant non-invasive cellular biomarkers for cancer patient prognosis, treatment selection, and treatment monitoring. Current CTC isolation approaches, such as immunoaffinity, filtration, or size-based techniques, are often limited by throughput, purity, large output volumes, or inability to obtain viable cells for downstream analysis. For all technologies, traditional immunofluorescent staining alone has been employed to distinguish and confirm the presence of isolated CTCs among contaminating blood cells, although cells isolated by size may express vastly different phenotypes. Consequently, CTC definitions have been non-trivial, researcher-dependent, and evolving. Here we describe a complete set of objective criteria, leveraging well-established cytomorphological features of malignancy, by which we identify large CTCs. We apply the criteria to CTCs enriched from stage IV lung and breast cancer patient blood samples using the High Throughput Vortex Chip (Vortex HT), an improved microfluidic technology for the label-free, size-based enrichment and concentration of rare cells. We achieve improved capture efficiency (up to 83%), high speed of processing (8 mL/min of 10x diluted blood, or 800 μL/min of whole blood), and high purity (avg. background of 28.8±23.6 white blood cells per mL of whole blood). We show markedly improved performance of CTC capture (84% positive test rate) in comparison to previous Vortex designs and the current FDA-approved gold standard CellSearch assay. The results demonstrate the ability to quickly collect viable and pure populations of abnormal large circulating cells unbiased by molecular characteristics, which helps uncover further heterogeneity in these cells. PMID:26863573

  15. Systematization of the Mechanism by Which Plasma Irradiation Causes Cell Growth and Tumor Cell Death

    NASA Astrophysics Data System (ADS)

    Shimizu, Nobuyuki

    2015-09-01

    New methods and technologies have improved minimally invasive surgical treatment and saved numerous patients. Recently, plasma irradiation has been demonstrated that might be useful in medical field and the plasma irradiation device is expected to become practically applicable. Mild plasma coagulator showed some advantages such as hemostasis and adhesion reduction in experimental animal model, but the mechanism of plasma irradiation remains unclear. Our study group aim to clarify the mechanism of plasma irradiation effects, mainly focusing on oxidative stress using cultured cell lines and small animal model. First, a study using cultured cell lines showed that the culture medium that was activated by plasma irradiation (we called this kind of medium as ``PAM'' -plasma activated medium-) induced tumor cell death. Although this effect was mainly found to be due to hydrogen peroxide, the remaining portion was considered as the specific effect of the plasma irradiation and we are now studying focusing on this effect. Second, we established a mouse intra-peritoneal adhesion model and checked biological reaction that occurred in the adhesion part. Histopathological study showed inflammatory cells infiltration into adhesion part and the expression of PTX3 that might involve tissue repair around adhesion part. We also confirmed that cytokines IL-6 and IL-10 might be useful as a marker of adhesion formation in this model. Applying ``PAM'' or mild plasma irradiation in this model, we examine the effects of plasma on inflamed cells. The samples in these experiments would be applied to targeted proteomics analysis, and we aim to demonstrate the systematization of the cell's reaction by plasma irradiation.

  16. The antiproliferative effect of bovine lactoferrin on canine mammary gland tumor cells.

    PubMed

    Yamada, Yuichi; Sato, Reeko; Kobayashi, Saori; Hankanga, Careen; Inanami, Osamu; Kuwabara, Mikinori; Momota, Yutaka; Tomizawa, Nobuyuki; Yasuda, Jun

    2008-05-01

    Lactoferrin has several biological activities, including antitumor activities in some human and animal tumor cells. Clinical trials have been carried out in human medicine based on these effects. However, the antitumor effects of lactoferrin in veterinary medicine remain unknown. In this in vitro study, we demonstrated that co-incubation of canine mammary gland tumor cells (CIPp and CHMp) and bovine lactoferrin induced growth arrest of tumor cells. This growth arrest was associated with induction of G1 arrest. Furthermore, this effect was stronger in tumor cells than in normal cells. These findings demonstrate that bovine lactoferrin has anti-tumor activity in canine mammary tumors and has the potential for use in tumor-bearing dogs.

  17. Soluble fibrin inhibits monocyte adherence and cytotoxicity against tumor cells: implications for cancer metastasis

    PubMed Central

    Biggerstaff, John P; Weidow, Brandy; Vidosh, Jacqueline; Dexheimer, Judith; Patel, Shonak; Patel, Pretesh

    2006-01-01

    Background Soluble fibrin (sFn) is a marker for disseminated intravascular coagulation and may have prognostic significance, especially in metastasis. However, a role for sFn in the etiology of metastatic cancer growth has not been extensively studied. We have reported that sFn cross-linked platelet binding to tumor cells via the major platelet fibrin receptor αIIbβ3, and tumor cell CD54 (ICAM-1), which is the receptor for two of the leukocyte β2 integrins (αLβ2 and aMβ2). We hypothesized that sFn may also affect leukocyte adherence, recognition, and killing of tumor cells. Furthermore, in a rat experimental metastasis model sFn pre-treatment of tumor cells enhanced metastasis by over 60% compared to untreated cells. Other studies have shown that fibrin(ogen) binds to the monocyte integrin αMβ2. This study therefore sought to investigate the effect of sFn on β2 integrin mediated monocyte adherence and killing of tumor cells. Methods The role of sFn in monocyte adherence and cytotoxicity against tumor cells was initially studied using static microplate adherence and cytotoxicity assays, and under physiologically relevant flow conditions in a microscope perfusion incubator system. Blocking studies were performed using monoclonal antibodies specific for β2 integrins and CD54, and specific peptides which inhibit sFn binding to these receptors. Results Enhancement of monocyte/tumor cell adherence was observed when only one cell type was bound to sFn, but profound inhibition was observed when sFn was bound to both monocytes and tumor cells. This effect was also reflected in the pattern of monocyte cytotoxicity. Studies using monoclonal blocking antibodies and specific blocking peptides (which did not affect normal coagulation) showed that the predominant mechanism of fibrin inhibition is via its binding to αMβ2 on monocytes, and to CD54 on both leukocytes and tumor cells. Conclusion sFn inhibits monocyte adherence and cytotoxicity of tumor cells by blocking

  18. Enhanced relative biological effectiveness of proton radiotherapy in tumor cells with internalized gold nanoparticles

    SciTech Connect

    Polf, Jerimy C.; Gillin, Michael; Bronk, Lawrence F.; Driessen, Wouter H. P.; Arap, Wadih; Pasqualini, Renata

    2011-05-09

    The development and use of sensitizing agents to improve the effectiveness of radiotherapy have long been sought to improve our ability to treat cancer. In this letter, we have studied the relative biological effectiveness of proton beam radiotherapy on prostate tumor cells with and without internalized gold nanoparticles. The effectiveness of proton radiotherapy for the killing of prostate tumor cells was increased by approximately 15%-20% for those cells containing internalized gold nanoparticles.

  19. Lymphocyte response to autochthonous human solid tumor cells: relationship to histological types and tumor load.

    PubMed

    Kurosu, Y; Honjo, H; Hironaka, T; Morita, K

    1979-12-01

    Mixed lymphocyte--tumor cell cultures were made with materials from patients with various histological types of cancer. In 25 out of 89 patients, positive lymphocyte response to tumor cells was observed. There appeared to be an inverse relationship between the frequency of positive responses and extent of the disease. Patients with neuroblastoma, however, showed more frequent positive responses in cases of widespread disease. The data obtained may have valuable clinical implications, supporting the possibility of immunotherapy of cancer patients.

  20. Enhanced relative biological effectiveness of proton radiotherapy in tumor cells with internalized gold nanoparticles

    NASA Astrophysics Data System (ADS)

    Polf, Jerimy C.; Bronk, Lawrence F.; Driessen, Wouter H. P.; Arap, Wadih; Pasqualini, Renata; Gillin, Michael

    2011-05-01

    The development and use of sensitizing agents to improve the effectiveness of radiotherapy have long been sought to improve our ability to treat cancer. In this letter, we have studied the relative biological effectiveness of proton beam radiotherapy on prostate tumor cells with and without internalized gold nanoparticles. The effectiveness of proton radiotherapy for the killing of prostate tumor cells was increased by approximately 15%-20% for those cells containing internalized gold nanoparticles.

  1. Maspin Expression in Prostate Tumor Cells Averts Stemness and Stratifies Drug Sensitivity

    PubMed Central

    Bernardo, M. Margarida; Kaplun, Alexander; Dzinic, Sijana H.; Li, Xiaohua; Irish, Jonathan; Mujagic, Adelina; Jakupovic, Benjamin; Back, Jessica B.; Van Buren, Eric; Han, Xiang; Dean, Ivory; Chen, Yong Q.; Heath, Elisabeth; Sakr, Wael; Sheng, Shijie

    2015-01-01

    Future curative cancer chemotherapies have to overcome tumor cell heterogeneity and plasticity. To test the hypothesis that the tumor suppressor maspin may reduce microenvironment-dependent prostate tumor cell plasticity and thereby modulate drug sensitivity, we established a new schematic combination of 2D, 3D and suspension cultures to enrich prostate cancer cell subpopulations with distinct differentiation potentials. We report here that, depending on the level of maspin expression, tumor cells in suspension and 3D collagen I manifest the phenotypes of stem-like and dormant tumor cell populations, respectively. In suspension, the surviving maspin-expressing tumor cells lost the self-renewal capacity, underwent senescence, lost the ability to dedifferentiate in vitro and failed to generate tumors in vivo. Maspin-nonexpressing tumor cells that survived the suspension culture in compact tumorspheres, displayed a higher level of stem cell marker expression, maintained the self-renewal capacity, formed tumorspheres in 3D matrices in vitro and were tumorigenic in vivo. The drug sensitivities of the distinct cell subpopulations depend on the drug target and the differentiation state of the cells. In 2D, Docetaxel, MS275 and Salinomycin were all cytotoxic. In suspension, while MS275 and Salinomycin were toxic, Docetaxel showed no effect. Interestingly, cells adapted to 3D collagen I were only responsive to Salinomycin. Maspin expression correlated with higher sensitivity to MS275 in both 2D and suspension, and to Salinomycin in 2D and 3D collagen I. Our data suggest that maspin reduces prostate tumor cell plasticity, and enhances tumor sensitivity to Salinomycin which may hold promise in overcoming tumor cell heterogeneity and plasticity. PMID:26208903

  2. Diagnostics of tumor cells by combination of Raman spectroscopy and microfluidics

    NASA Astrophysics Data System (ADS)

    Neugebauer, U.; Dochow, S.; Krafft, C.; Bocklitz, T.; Clement, J. H.; Popp, J.

    2011-07-01

    Circulating epithelial tumor cells are of increasing importance for tumor diagnosis and therapy monitoring of cancer patients. The definite identification of the rare tumor cells within numerous blood cells is challenging. Therefore, within the research initiative "Jenaer Zell-Identifizierungs-Gruppe" (JenZIG) we develop new methods for cell identification, micromanipulation and sorting based on spectroscopic methods and microfluidic systems. In this contribution we show, that classification models based on Raman spectroscopic analysis allow a precise discrimination of tumor cells from non-tumor cells with high prediction accuracies, up to more than 99% for dried cells. That holds true for unknown cell mixtures (tumor cells and leukocytes/erythrocytes) under dried conditions as well as in solution using the Raman laser as an optical tweezers to keep the cells in focus. We extended our studies by using a capillary system consisting of a quartz capillary, fiber optics and an adjustable fitting to trap cells. This system allows a prediction accuracy of 92.2% on the single cell level, and is a prerequisite for the development of a cell sorting and identification device based on a microfluidic chip. Initial experiments show that tumor cell lines can be differentiated from healthy leukocyte cells with an accuracy of more than 98%.

  3. Ghrelin promotes oral tumor cell proliferation by modifying GLUT1 expression.

    PubMed

    Kraus, Dominik; Reckenbeil, Jan; Wenghoefer, Matthias; Stark, Helmut; Frentzen, Matthias; Allam, Jean-Pierre; Novak, Natalija; Frede, Stilla; Götz, Werner; Probstmeier, Rainer; Meyer, Rainer; Winter, Jochen

    2016-03-01

    In our study, ghrelin was investigated with respect to its capacity on proliferative effects and molecular correlations on oral tumor cells. The presence of all molecular components of the ghrelin system, i.e., ghrelin and its receptors, was analyzed and could be detected using real-time PCR and immunohistochemistry. To examine cellular effects caused by ghrelin and to clarify downstream-regulatory mechanisms, two different oral tumor cell lines (BHY and HN) were used in cell culture experiments. Stimulation of either cell line with ghrelin led to a significantly increased proliferation. Signal transduction occurred through phosphorylation of GSK-3β and nuclear translocation of β-catenin. This effect could be inhibited by blocking protein kinase A. Glucose transporter1 (GLUT1), as an important factor for delivering sufficient amounts of glucose to tumor cells having high requirements for this carbohydrate (Warburg effect) was up-regulated by exogenous and endogenous ghrelin. Silencing intracellular ghrelin concentrations using siRNA led to a significant decreased expression of GLUT1 and proliferation. In conclusion, our study describes the role for the appetite-stimulating peptide hormone ghrelin in oral cancer proliferation under the particular aspect of glucose uptake: (1) tumor cells are a source of ghrelin. (2) Ghrelin affects tumor cell proliferation through autocrine and/or paracrine activity. (3) Ghrelin modulates GLUT1 expression and thus indirectly enhances tumor cell proliferation. These findings are of major relevance, because glucose uptake is assumed to be a promising target for cancer treatment.

  4. Inhibition of adhesion and proliferation of peritoneally disseminated tumor cells by pegylated catalase.

    PubMed

    Hyoudou, Kenji; Nishikawa, Makiya; Kobayashi, Yuki; Kuramoto, Yukari; Yamashita, Fumiyoshi; Hashida, Mitsuru

    2006-01-01

    Hydrogen peroxide may aggravate the peritoneal dissemination of tumor cells by activating the expression of a variety of genes. In this study, we used pegylated catalase (PEG-catalase) to examine whether prolonged retention of catalase activity within the peritoneal cavity is effective in inhibiting peritoneal dissemination in mouse models. Murine B16-BL6 cells or colon 26 cells labeled with firefly luciferase gene were inoculated intraperitoneally into syngeneic mice. Compared with unmodified catalase, PEG-catalase was retained in the peritoneal cavity for a long period after intraperitoneal injection. A single injection of PEG-catalase just before tumor inoculation significantly reduced the number of the tumor cells at 1 and 7 days. The changes in the expression of molecules involved in the metastasis were evaluated by real time quantitative PCR analysis. Inoculation of the tumor cells increased the expression of intercellular adhesion molecule (ICAM)-1 in the greater omentum, which was inhibited by PEG-catalase. An injection of PEG-catalase at 3 days after tumor inoculation also reduced the number of the tumor cells, suggesting that processes other than the adhesion of tumor cells to peritoneal organs are also inhibited. Daily doses of PEG-catalase significantly prolonged the survival time of tumor-bearing mice. These results indicate that intraperitoneal injection of PEG-catalase inhibits the multiple processes of peritoneal dissemination of tumor cells by scavenging hydrogen peroxide in the peritoneal cavity. PMID:17086358

  5. Arctigenin preferentially induces tumor cell death under glucose deprivation by inhibiting cellular energy metabolism.

    PubMed

    Gu, Yuan; Qi, Chunting; Sun, Xiaoxiao; Ma, Xiuquan; Zhang, Haohao; Hu, Lihong; Yuan, Junying; Yu, Qiang

    2012-08-15

    Selectively eradicating cancer cells with minimum adverse effects on normal cells is a major challenge in the development of anticancer therapy. We hypothesize that nutrient-limiting conditions frequently encountered by cancer cells in poorly vascularized solid tumors might provide an opportunity for developing selective therapy. In this study, we investigated the function and molecular mechanisms of a natural compound, arctigenin, in regulating tumor cell growth. We demonstrated that arctigenin selectively promoted glucose-starved A549 tumor cells to undergo necrosis by inhibiting mitochondrial respiration. In doing so, arctigenin elevated cellular level of reactive oxygen species (ROS) and blocked cellular energy metabolism in the glucose-starved tumor cells. We also demonstrated that cellular ROS generation was caused by intracellular ATP depletion and played an essential role in the arctigenin-induced tumor cell death under the glucose-limiting condition. Furthermore, we combined arctigenin with the glucose analogue 2-deoxyglucose (2DG) and examined their effects on tumor cell growth. Interestingly, this combination displayed preferential cell-death inducing activity against tumor cells compared to normal cells. Hence, we propose that the combination of arctigenin and 2DG may represent a promising new cancer therapy with minimal normal tissue toxicity.

  6. Intraoperative near-infrared fluorescence imaging and spectroscopy identifies residual tumor cells in wounds.

    PubMed

    Holt, David; Parthasarathy, Ashwin B; Okusanya, Olugbenga; Keating, Jane; Venegas, Ollin; Deshpande, Charuhas; Karakousis, Giorgos; Madajewski, Brian; Durham, Amy; Nie, Shuming; Yodh, Arjun G; Singhal, Sunil

    2015-07-01

    Surgery is the most effective method to cure patients with solid tumors, and 50% of all cancer patients undergo resection. Local recurrences are due to tumor cells remaining in the wound, thus we explore near-infrared (NIR) fluorescence spectroscopy and imaging to identify residual cancer cells after surgery. Fifteen canines and two human patients with spontaneously occurring sarcomas underwent intraoperative imaging. During the operation, the wounds were interrogated with NIR fluorescence imaging and spectroscopy. NIR monitoring identified the presence or absence of residual tumor cells after surgery in 14/15 canines with a mean fluorescence signal-to-background ratio (SBR) of ∼16 . Ten animals showed no residual tumor cells in the wound bed (mean SBR<2 , P<0.001 ). None had a local recurrence at >1-year follow-up. In five animals, the mean SBR of the wound was >15 , and histopathology confirmed tumor cells in the postsurgical wound in four/five canines. In the human pilot study, neither patient had residual tumor cells in the wound bed, and both remain disease free at >1.5-year follow up. Intraoperative NIR fluorescence imaging and spectroscopy identifies residual tumor cells in surgical wounds. These observations suggest that NIR imaging techniques may improve tumor resection during cancer operations.

  7. Combination treatment with decitabine and ionizing radiation enhances tumor cells susceptibility of T cells

    PubMed Central

    Son, Cheol-Hun; Lee, Hong-Rae; Koh, Eun-Kyoung; Shin, Dong-Yeok; Bae, Jae-Ho; Yang, Kwangmo; Park, You-Soo

    2016-01-01

    Decitabine has been found to have anti-metabolic and anti-tumor activities in various tumor cells. Recently, the use of decitabine in combination with other conventional therapies reportedly resulted in improved anti-tumor activity against various tumors. Ionizing radiation (IR) is widely used as a cancer treatment. Decitabine and IR improve immunogenicity and susceptibility of tumor cells to immune cells by up-regulating the expression of various molecules such as major histocompatibility complex (MHC) class I; natural-killer group 2, member D (NKG2D) ligands; and co-stimulatory molecules. However, the effects of combining decitabine and IR therapies are largely unknown. Our results indicate that decitabine or IR treatment upregulates MHC class I, along with various co-stimulatory molecules in target tumor cells. Furthermore, decitabine and IR combination treatment further upregulates MHC class I, along with the co-stimulatory molecules, when compared to the effect of each treatment alone. Importantly, decitabine treatment further enhanced T cell-mediated cytotoxicity and release of IFN- γ against target tumor cells which is induced by IR. Interestingly, decitabine did not affect NKG2D ligand expression or NK cell-mediated cytotoxicity in target tumor cells. These observations suggest that decitabine may be used as a useful immunomodulator to sensitize tumor cells in combination with other tumor therapies. PMID:27671170

  8. Intraoperative near-infrared fluorescence imaging and spectroscopy identifies residual tumor cells in wounds

    NASA Astrophysics Data System (ADS)

    Holt, David; Parthasarathy, Ashwin B.; Okusanya, Olugbenga; Keating, Jane; Venegas, Ollin; Deshpande, Charuhas; Karakousis, Giorgos; Madajewski, Brian; Durham, Amy; Nie, Shuming; Yodh, Arjun G.; Singhal, Sunil

    2015-07-01

    Surgery is the most effective method to cure patients with solid tumors, and 50% of all cancer patients undergo resection. Local recurrences are due to tumor cells remaining in the wound, thus we explore near-infrared (NIR) fluorescence spectroscopy and imaging to identify residual cancer cells after surgery. Fifteen canines and two human patients with spontaneously occurring sarcomas underwent intraoperative imaging. During the operation, the wounds were interrogated with NIR fluorescence imaging and spectroscopy. NIR monitoring identified the presence or absence of residual tumor cells after surgery in 14/15 canines with a mean fluorescence signal-to-background ratio (SBR) of ˜16. Ten animals showed no residual tumor cells in the wound bed (mean SBR<2, P<0.001). None had a local recurrence at >1-year follow-up. In five animals, the mean SBR of the wound was >15, and histopathology confirmed tumor cells in the postsurgical wound in four/five canines. In the human pilot study, neither patient had residual tumor cells in the wound bed, and both remain disease free at >1.5-year follow up. Intraoperative NIR fluorescence imaging and spectroscopy identifies residual tumor cells in surgical wounds. These observations suggest that NIR imaging techniques may improve tumor resection during cancer operations.

  9. Intraoperative near-infrared fluorescence imaging and spectroscopy identifies residual tumor cells in wounds

    PubMed Central

    Holt, David; Parthasarathy, Ashwin B.; Okusanya, Olugbenga; Keating, Jane; Venegas, Ollin; Deshpande, Charuhas; Karakousis, Giorgos; Madajewski, Brian; Durham, Amy; Nie, Shuming; Yodh, Arjun G.; Singhal, Sunil

    2015-01-01

    Abstract. Surgery is the most effective method to cure patients with solid tumors, and 50% of all cancer patients undergo resection. Local recurrences are due to tumor cells remaining in the wound, thus we explore near-infrared (NIR) fluorescence spectroscopy and imaging to identify residual cancer cells after surgery. Fifteen canines and two human patients with spontaneously occurring sarcomas underwent intraoperative imaging. During the operation, the wounds were interrogated with NIR fluorescence imaging and spectroscopy. NIR monitoring identified the presence or absence of residual tumor cells after surgery in 14/15 canines with a mean fluorescence signal-to-background ratio (SBR) of ∼16. Ten animals showed no residual tumor cells in the wound bed (mean SBR<2, P<0.001). None had a local recurrence at >1-year follow-up. In five animals, the mean SBR of the wound was >15, and histopathology confirmed tumor cells in the postsurgical wound in four/five canines. In the human pilot study, neither patient had residual tumor cells in the wound bed, and both remain disease free at >1.5-year follow up. Intraoperative NIR fluorescence imaging and spectroscopy identifies residual tumor cells in surgical wounds. These observations suggest that NIR imaging techniques may improve tumor resection during cancer operations. PMID:26160347

  10. Glioblastoma: A Pathogenic Crosstalk between Tumor Cells and Pericytes

    PubMed Central

    Redondo-Garcia, Carolina; Martinez, Salvador

    2014-01-01

    Cancers likely originate in progenitor zones containing stem cells and perivascular stromal cells. Much evidence suggests stromal cells play a central role in tumor initiation and progression. Brain perivascular cells (pericytes) are contractile and function normally to regulate vessel tone and morphology, have stem cell properties, are interconvertible with macrophages and are involved in new vessel formation during angiogenesis. Nevertheless, how pericytes contribute to brain tumor infiltration is not known. In this study we have investigated the underlying mechanism by which the most lethal brain cancer, Glioblastoma Multiforme (GBM) interacts with pre-existing blood vessels (co-option) to promote tumor initiation and progression. Here, using mouse xenografts and laminin-coated silicone substrates, we show that GBM malignancy proceeds via specific and previously unknown interactions of tumor cells with brain pericytes. Two-photon and confocal live imaging revealed that GBM cells employ novel, Cdc42-dependent and actin-based cytoplasmic extensions, that we call flectopodia, to modify the normal contractile activity of pericytes. This results in the co-option of modified pre-existing blood vessels that support the expansion of the tumor margin. Furthermore, our data provide evidence for GBM cell/pericyte fusion-hybrids, some of which are located on abnormally constricted vessels ahead of the tumor and linked to tumor-promoting hypoxia. Remarkably, inhibiting Cdc42 function impairs vessel co-option and converts pericytes to a phagocytic/macrophage-like phenotype, thus favoring an innate immune response against the tumor. Our work, therefore, identifies for the first time a key GBM contact-dependent interaction that switches pericyte function from tumor-suppressor to tumor-promoter, indicating that GBM may harbor the seeds of its own destruction. These data support the development of therapeutic strategies directed against co-option (preventing incorporation and

  11. Soluble fibrin augments platelet/tumor cell adherence in vitro and in vivo, and enhances experimental metastasis.

    PubMed

    Biggerstaff, J P; Seth, N; Amirkhosravi, A; Amaya, M; Fogarty, S; Meyer, T V; Siddiqui, F; Francis, J L

    1999-01-01

    There is considerable evidence for a relationship between hemostasis and malignancy. Since platelet adhesion to tumor cells has been implicated in the metastatic process and plasma levels of fibrinogen (Fg) and soluble fibrin (sFn) monomer are increased in cancer, we hypothesized that these molecules might enhance tumor-platelet interaction. We therefore studied binding of sFn monomer to tumor cells in a static microplate adhesion assay and determined the effect of pre-treating tumor cells with sFn on tumor cell-induced thrombocytopenia and experimental metastasis. Soluble fibrin (produced by adding thrombin to FXIII- and plasminogen-free Fg in the presence of Gly-Pro-Arg-Pro-amide (GPRP-NH2) significantly increased platelet adherence to tumor cells. This effect was primarily mediated by the integrins alphaIIb beta3 on the platelet and CD 54 (ICAM-1) on the tumor cells. Platelets adhered to untreated A375 cells (28 +/- 8 platelets/tumor cell) and this was not significantly affected by pre-treatment of the tumor cells with fibrinogen or GPRP-NH2. Although thrombin treatment increased adherence, pre-incubation of the tumor cells with sFn resulted in a further increase in platelet binding to tumor cells. In contrast to untreated tumor cells, intravenous injection of sFn-treated A 375 cells reduced the platelet count in anticoagulated mice, supporting the in vitro finding that sFn enhanced tumor cell-platelet adherence. In a more aggressive model of experimental metastasis, treating tumor cells with sFn enhanced lung seeding by 65% compared to untreated cells. Extrapolation of our data to the clinical situation suggests that coagulation activation, and subsequent increase in circulating Fn monomer, may enhance platelet adhesion to circulating tumor cells and thereby facilitate metastatic spread.

  12. Soluble fibrin augments platelet/tumor cell adherence in vitro and in vivo, and enhances experimental metastasis.

    PubMed

    Biggerstaff, J P; Seth, N; Amirkhosravi, A; Amaya, M; Fogarty, S; Meyer, T V; Siddiqui, F; Francis, J L

    1999-01-01

    There is considerable evidence for a relationship between hemostasis and malignancy. Since platelet adhesion to tumor cells has been implicated in the metastatic process and plasma levels of fibrinogen (Fg) and soluble fibrin (sFn) monomer are increased in cancer, we hypothesized that these molecules might enhance tumor-platelet interaction. We therefore studied binding of sFn monomer to tumor cells in a static microplate adhesion assay and determined the effect of pre-treating tumor cells with sFn on tumor cell-induced thrombocytopenia and experimental metastasis. Soluble fibrin (produced by adding thrombin to FXIII- and plasminogen-free Fg in the presence of Gly-Pro-Arg-Pro-amide (GPRP-NH2) significantly increased platelet adherence to tumor cells. This effect was primarily mediated by the integrins alphaIIb beta3 on the platelet and CD 54 (ICAM-1) on the tumor cells. Platelets adhered to untreated A375 cells (28 +/- 8 platelets/tumor cell) and this was not significantly affected by pre-treatment of the tumor cells with fibrinogen or GPRP-NH2. Although thrombin treatment increased adherence, pre-incubation of the tumor cells with sFn resulted in a further increase in platelet binding to tumor cells. In contrast to untreated tumor cells, intravenous injection of sFn-treated A 375 cells reduced the platelet count in anticoagulated mice, supporting the in vitro finding that sFn enhanced tumor cell-platelet adherence. In a more aggressive model of experimental metastasis, treating tumor cells with sFn enhanced lung seeding by 65% compared to untreated cells. Extrapolation of our data to the clinical situation suggests that coagulation activation, and subsequent increase in circulating Fn monomer, may enhance platelet adhesion to circulating tumor cells and thereby facilitate metastatic spread. PMID:10919717

  13. Vinculin contributes to Cell Invasion by Regulating Contractile Activation

    NASA Astrophysics Data System (ADS)

    Mierke, Claudia Tanja

    2008-07-01

    Vinculin is a component of the focal adhesion complex and is described as a mechano-coupling protein connecting the integrin receptor and the actin cytoskeleton. Vinculin knock-out (k.o.) cells (vin-/-) displayed increased migration on a 2-D collagen- or fibronectin-coated substrate compared to wildtype cells, but the role of vinculin in cell migration through a 3-D connective tissue is unknown. We determined the invasiveness of established tumor cell lines using a 3-D collagen invasion assay. Gene expression analysis of 4 invasive and 4 non-invasive tumor cell lines revealed that vinculin expression was significantly increased in invasive tumor cell lines. To analyze the mechanisms by which vinculin increased cell invasion in a 3-D gel, we studied mouse embryonic fibroblasts wildtype and vin-/- cells. Wildtype cells were 3-fold more invasive compared vin-/- cells. We hypothesized that the ability to generate sufficient traction forces is a prerequisite for tumor cell migration in a 3-D connective tissue matrix. Using traction microscopy, we found that wildtype exerted 3-fold higher tractions on fibronectin-coated polyacrylamide gels compared to vin-/- cells. These results show that vinculin controls two fundamental functions that lead to opposite effects on cell migration in a 2-D vs. a 3-D environment: On the one hand, vinculin stabilizes the focal adhesions (mechano-coupling function) and thereby reduces motility in 2-D. On the other hand, vinculin is also a potent activator of traction generation (mechano-regulating function) that is important for cell invasion in a 3-D environment.

  14. Release of Membrane-Bound Vesicles and Inhibition of Tumor Cell Adhesion by the Peptide Neopetrosiamide A

    PubMed Central

    Austin, Pamela; Heller, Markus; Williams, David E.; McIntosh, Lawrence P.; Vogl, A. Wayne; Foster, Leonard J.; Andersen, Raymond J.; Roberge, Michel; Roskelley, Calvin D.

    2010-01-01

    Background Neopetrosiamide A (NeoA) is a 28-amino acid tricyclic peptide originally isolated from a marine sponge as a tumor cell invasion inhibitor whose mechanism of action is unknown. Methodology/Principal Findings We show that NeoA reversibly inhibits tumor cell adhesion, disassembles focal adhesions in pre-attached cells, and decreases the level of β1 integrin subunits on the cell surface. NeoA also induces the formation of dynamic, membrane-bound protrusions on the surface of treated cells and the release of membrane-bound vesicles into the culture medium. Proteomic analysis indicates that the vesicles contain EGF and transferrin receptors as well as a number of proteins involved in adhesion and migration including: β1 integrin and numerous α integrin subunits; actin and actin-binding proteins such as cofilin, moesin and myosin 1C; and membrane modulating eps15 homology domain (EHD) proteins. Surface labeling, trafficking inhibition, and real-time imaging experiments all suggest that β1 integrin-containing vesicles are released directly from NeoA-induced cell surface protrusions rather than from vesicles generated intracellularly. The biological activity of NeoA is dependent on its disulfide bond pattern and NMR spectroscopy indicates that the peptide is globular with a continuous ridge of hydrophobic groups flanked by charged amino acid residues that could facilitate a simultaneous interaction with lipids and proteins in the membrane. Conclusions/Significance NeoA is an anti-adhesive peptide that decreases cell surface integrin levels through a novel, yet to be elucidated, mechanism that involves the release of adhesion molecule-containing vesicles from the cell surface. PMID:20520768

  15. Combination therapy targeting both cancer stem-like cells and bulk tumor cells for improved efficacy of breast cancer treatment.

    PubMed

    Wang, Tao; Narayanaswamy, Radhika; Ren, Huilan; Torchilin, Vladimir P

    2016-06-01

    Many types of tumors are organized in a hierarchy of heterogeneous cell populations. The cancer stem-like cells (CSCs) hypothesis suggests that tumor development and metastasis are driven by a minority population of cells, which are responsible for tumor initiation, growth and recurrences. The inability to efficiently eliminate CSCs during chemotherapy, together with CSCs being highly tumorigenic and invasive, may result in treatment failure due to cancer relapse and metastases. CSCs are emerging as a promising target for the development of translational cancer therapies. Ideal panacea for cancer would kill all malignant cells, including CSCs and bulk tumor cells. Since both chemotherapy and CSCs-specific therapy are insufficient to cure cancer, we propose combination therapy with CSCs-targeted agents and chemotherapeutics for improved breast cancer treatment. We generated in vitro mammosphere of 2 breast cancer cell lines, and demonstrated ability of mammospheres to grow and enrich cancer cells with stem-like properties, including self-renewal, multilineage differentiation and enrichment of cells expressing breast cancer stem-like cell biomarkers CD44(+)/CD24(-/low). The formation of mammospheres was significantly inhibited by salinomycin, validating its pharmacological role against the cancer stem-like cells. In contrast, paclitaxel showed a minimal effect on the proliferation and growth of breast cancer stem-like cells. While combination therapies of salinomycin with conventional chemotherapy (paclitaxel or lipodox) showed a potential to improve tumor cell killing, different subtypes of breast cancer cells showed different patterns in response to the combination therapies. While optimization of combination therapy is warranted, the design of combination therapy should consider phenotypic attributes of breast cancer types. PMID:27259361

  16. Combination therapy targeting both cancer stem-like cells and bulk tumor cells for improved efficacy of breast cancer treatment.

    PubMed

    Wang, Tao; Narayanaswamy, Radhika; Ren, Huilan; Torchilin, Vladimir P

    2016-06-01

    Many types of tumors are organized in a hierarchy of heterogeneous cell populations. The cancer stem-like cells (CSCs) hypothesis suggests that tumor development and metastasis are driven by a minority population of cells, which are responsible for tumor initiation, growth and recurrences. The inability to efficiently eliminate CSCs during chemotherapy, together with CSCs being highly tumorigenic and invasive, may result in treatment failure due to cancer relapse and metastases. CSCs are emerging as a promising target for the development of translational cancer therapies. Ideal panacea for cancer would kill all malignant cells, including CSCs and bulk tumor cells. Since both chemotherapy and CSCs-specific therapy are insufficient to cure cancer, we propose combination therapy with CSCs-targeted agents and chemotherapeutics for improved breast cancer treatment. We generated in vitro mammosphere of 2 breast cancer cell lines, and demonstrated ability of mammospheres to grow and enrich cancer cells with stem-like properties, including self-renewal, multilineage differentiation and enrichment of cells expressing breast cancer stem-like cell biomarkers CD44(+)/CD24(-/low). The formation of mammospheres was significantly inhibited by salinomycin, validating its pharmacological role against the cancer stem-like cells. In contrast, paclitaxel showed a minimal effect on the proliferation and growth of breast cancer stem-like cells. While combination therapies of salinomycin with conventional chemotherapy (paclitaxel or lipodox) showed a potential to improve tumor cell killing, different subtypes of breast cancer cells showed different patterns in response to the combination therapies. While optimization of combination therapy is warranted, the design of combination therapy should consider phenotypic attributes of breast cancer types.

  17. p53 Restoration in Induction and Maintenance of Senescence: Differential Effects in Premalignant and Malignant Tumor Cells.

    PubMed

    Harajly, Mohamad; Zalzali, Hasan; Nawaz, Zafar; Ghayad, Sandra E; Ghamloush, Farah; Basma, Hussein; Zainedin, Samiha; Rabeh, Wissam; Jabbour, Mark; Tawil, Ayman; Badro, Danielle A; Evan, Gerard I; Saab, Raya

    2016-02-01

    The restoration of p53 has been suggested as a therapeutic approach in tumors. However, the timing of p53 restoration in relation to its efficacy during tumor progression still is unclear. We now show that the restoration of p53 in murine premalignant proliferating pineal lesions resulted in cellular senescence, while p53 restoration in invasive pineal tumors did not. The effectiveness of p53 restoration was not dependent on p19(Arf) expression but showed an inverse correlation with Mdm2 expression. In tumor cells, p53 restoration became effective when paired with either DNA-damaging therapy or with nutlin, an inhibitor of p53-Mdm2 interaction. Interestingly, the inactivation of p53 after senescence resulted in reentry into the cell cycle and rapid tumor progression. The evaluation of a panel of human supratentorial primitive neuroectodermal tumors (sPNET) showed low activity of the p53 pathway. Together, these data suggest that the restoration of the p53 pathway has different effects in premalignant versus invasive pineal tumors, and that p53 activation needs to be continually sustained, as reversion from senescence occurs rapidly with aggressive tumor growth when p53 is lost again. Finally, p53 restoration approaches may be worth exploring in sPNET, where the p53 gene is intact but the pathway is inactive in the majority of examined tumors. PMID:26598601

  18. Dissecting the Heterogeneity of Circulating Tumor Cells in Metastatic Breast Cancer: Going Far Beyond the Needle in the Haystack

    PubMed Central

    Bulfoni, Michela; Turetta, Matteo; Del Ben, Fabio; Di Loreto, Carla; Beltrami, Antonio Paolo; Cesselli, Daniela

    2016-01-01

    Although the enumeration of circulating tumor cells (CTC) defined as expressing both epithelial cell adhesion molecule and cytokeratins (EpCAM+/CK+) can predict prognosis and response to therapy in metastatic breast, colon and prostate cancer, its clinical utility (i.e., the ability to improve patient outcome by guiding therapy) has not yet been proven in clinical trials. Therefore, scientists are now focusing on the molecular characterization of CTC as a way to explore its possible use as a “surrogate” of tumor tissues to non-invasively assess the genomic landscape of the cancer and its evolution during treatment. Additionally, evidences confirm the existence of CTC in epithelial-to-mesenchymal transition (EMT) characterized by a variable loss of epithelial markers. Since the EMT process can originate cells with enhanced invasiveness, stemness and drug-resistance, the enumeration and characterization of this population, perhaps the one truly responsible of tumor recurrence and progression, could be more clinically useful. For these reasons, several devices able to capture CTC independently from the expression of epithelial markers have been developed. In this review, we will describe the types of heterogeneity so far identified and the key role played by the epithelial-to-mesenchymal transition in driving CTC heterogeneity. The clinical relevance of detecting CTC-heterogeneity will be discussed as well. PMID:27783057

  19. p53 Restoration in Induction and Maintenance of Senescence: Differential Effects in Premalignant and Malignant Tumor Cells

    PubMed Central

    Harajly, Mohamad; Zalzali, Hasan; Nawaz, Zafar; Ghayad, Sandra E.; Ghamloush, Farah; Basma, Hussein; Zainedin, Samiha; Rabeh, Wissam; Jabbour, Mark; Tawil, Ayman; Badro, Danielle A.; Evan, Gerard I.

    2015-01-01

    The restoration of p53 has been suggested as a therapeutic approach in tumors. However, the timing of p53 restoration in relation to its efficacy during tumor progression still is unclear. We now show that the restoration of p53 in murine premalignant proliferating pineal lesions resulted in cellular senescence, while p53 restoration in invasive pineal tumors did not. The effectiveness of p53 restoration was not dependent on p19Arf expression but showed an inverse correlation with Mdm2 expression. In tumor cells, p53 restoration became effective when paired with either DNA-damaging therapy or with nutlin, an inhibitor of p53-Mdm2 interaction. Interestingly, the inactivation of p53 after senescence resulted in reentry into the cell cycle and rapid tumor progression. The evaluation of a panel of human supratentorial primitive neuroectodermal tumors (sPNET) showed low activity of the p53 pathway. Together, these data suggest that the restoration of the p53 pathway has different effects in premalignant versus invasive pineal tumors, and that p53 activation needs to be continually sustained, as reversion from senescence occurs rapidly with aggressive tumor growth when p53 is lost again. Finally, p53 restoration approaches may be worth exploring in sPNET, where the p53 gene is intact but the pathway is inactive in the majority of examined tumors. PMID:26598601

  20. OASIS/CREB3L1 is epigenetically silenced in human bladder cancer facilitating tumor cell spreading and migration in vitro

    PubMed Central

    Rose, Michael; Schubert, Claudia; Dierichs, Laura; Gaisa, Nadine T; Heer, Matthias; Heidenreich, Axel; Knüchel, Ruth; Dahl, Edgar

    2014-01-01

    CREB3L1 has been recently proposed as a novel metastasis suppressor gene in breast cancer. Our current study highlights CREB3L1 expression, regulation, and function in bladder cancer. We demonstrate a significant downregulation of CREB3L1 mRNA expression (n = 64) in primary bladder cancer tissues caused by tumor-specific CREB3L1 promoter hypermethylation (n = 51). Based on pyrosequencing CREB3L1 methylation was shown to be potentially associated with a more aggressive phenotype of bladder cancer. These findings were verified by an independent public data set containing data from 184 bladder tumors. In addition, immunohistochemical evaluation showed that CREB3L1 protein expression is decreased in bladder cancer tissues as well. Interestingly, protein loss is predominately observed in the nuclei of aggressive tumor cells. Based on in vitro models we clearly show that CREB3L1 re-expression mediates suppression of tumor cell migration and colony growth of high grade and invasive bladder cancer cells. The candidate tumor suppressor and TGF-β signaling inhibitor HTRA3 was furthermore identified as putative target gene of CREB3L1 in both invasive J82 bladder cells and primary bladder tumors. Hence, our data provide for the first time evidence that the transcription factor CREB3L1 may have an important role as a putative tumor suppressor in bladder cancer. PMID:25625847

  1. Historical biogeography of the fern genus Deparia (Athyriaceae) and its relation with polyploidy.

    PubMed

    Kuo, Li-Yaung; Ebihara, Atsushi; Shinohara, Wataru; Rouhan, Germinal; Wood, Kenneth R; Wang, Chun-Neng; Chiou, Wen-Liang

    2016-11-01

    The wide geographical distribution of many fern species is related to their high dispersal ability. However, very limited studies surveyed biological traits that could contribute to colonization success after dispersal. In this study, we applied phylogenetic approaches to infer historical biogeography of the fern genus Deparia (Athyriaceae, Eupolypods II). Because polyploids are suggested to have better colonization abilities and are abundant in Deparia, we also examined whether polyploidy could be correlated to long-distance dispersal events and whether polyploidy could play a role in these dispersals/establishment and range expansion. Maximum likelihood and Bayesian phylogenetic reconstructions were based on a four-region combined cpDNA dataset (rps16-matK IGS, trnL-L-F, matK and rbcL; a total of 4252 characters) generated from 50 ingroup (ca. 80% of the species diversity) and 13 outgroup taxa. Using the same sequence alignment and maximum likelihood trees, we carried out molecular dating analyses. The resulting chronogram was used to reconstruct ancestral distribution using the DEC model and ancestral ploidy level using ChromEvol. We found that Deparia originated around 27.7Ma in continental Asia/East Asia. A vicariant speciation might account for the disjunctive distribution of East Asia-northeast North America. There were multiple independent long-distance dispersals to Africa/Madagascar (at least once), Southeast Asia (at least once), south Pacific islands (at least twice), Australia/New Guinea/New Zealand (at least once), and the Hawaiian Islands (at least once). In particular, the long-distance dispersal to the Hawaiian Islands was associated with polyploidization, and the dispersal rate was slightly higher in the polyploids than in diploids. Moreover, we found five species showing recent infraspecific range expansions, all of which took place concurrently with polyploidization. In conclusion, our study provides the first investigation using phylogenetic

  2. Historical biogeography of the fern genus Deparia (Athyriaceae) and its relation with polyploidy.

    PubMed

    Kuo, Li-Yaung; Ebihara, Atsushi; Shinohara, Wataru; Rouhan, Germinal; Wood, Kenneth R; Wang, Chun-Neng; Chiou, Wen-Liang

    2016-11-01

    The wide geographical distribution of many fern species is related to their high dispersal ability. However, very limited studies surveyed biological traits that could contribute to colonization success after dispersal. In this study, we applied phylogenetic approaches to infer historical biogeography of the fern genus Deparia (Athyriaceae, Eupolypods II). Because polyploids are suggested to have better colonization abilities and are abundant in Deparia, we also examined whether polyploidy could be correlated to long-distance dispersal events and whether polyploidy could play a role in these dispersals/establishment and range expansion. Maximum likelihood and Bayesian phylogenetic reconstructions were based on a four-region combined cpDNA dataset (rps16-matK IGS, trnL-L-F, matK and rbcL; a total of 4252 characters) generated from 50 ingroup (ca. 80% of the species diversity) and 13 outgroup taxa. Using the same sequence alignment and maximum likelihood trees, we carried out molecular dating analyses. The resulting chronogram was used to reconstruct ancestral distribution using the DEC model and ancestral ploidy level using ChromEvol. We found that Deparia originated around 27.7Ma in continental Asia/East Asia. A vicariant speciation might account for the disjunctive distribution of East Asia-northeast North America. There were multiple independent long-distance dispersals to Africa/Madagascar (at least once), Southeast Asia (at least once), south Pacific islands (at least twice), Australia/New Guinea/New Zealand (at least once), and the Hawaiian Islands (at least once). In particular, the long-distance dispersal to the Hawaiian Islands was associated with polyploidization, and the dispersal rate was slightly higher in the polyploids than in diploids. Moreover, we found five species showing recent infraspecific range expansions, all of which took place concurrently with polyploidization. In conclusion, our study provides the first investigation using phylogenetic

  3. MERTK Inhibition Induces Polyploidy and Promotes Cell Death and Cellular Senescence in Glioblastoma Multiforme

    PubMed Central

    Sufit, Alexandra; Lee-Sherick, Alisa B.; DeRyckere, Deborah; Rupji, Manali; Dwivedi, Bhakti; Varella-Garcia, Marileila; Pierce, Angela M.; Kowalski, Jeanne; Wang, Xiaodong; Frye, Stephen V.; Earp, H. Shelton

    2016-01-01

    Background MER receptor tyrosine kinase (MERTK) is expressed in a variety of malignancies, including glioblastoma multiforme (GBM). Our previous work demonstrated that inhibition of MERTK using RNA interference induced cell death and chemosensitivity in GBM cells, implicating MERTK as a potential therapeutic target. Here we investigate whether a novel MERTK-selective small molecule tyrosine kinase inhibitor, UNC2025, has similar anti-tumor effects in GBM cell lines. Methods Correlations between expression of GAS6, a MERTK ligand, and prognosis were determined using data from the TCGA database. GBM cell lines (A172, SF188, U251) were treated in vitro with increasing doses of UNC2025 (50-400nM). Cell count and viability were determined by trypan blue exclusion. Cell cycle profiles and induction of apoptosis were assessed by flow cytometric analysis after BrdU or Po-Pro-1/propidium iodide staining, respectively. Polyploidy was detected by propidium iodide staining and metaphase spread. Cellular senescence was determined by β-galactosidase staining and senescence-associated secretory cytokine analysis. Results Decreased overall survival significantly correlated with high levels of GAS6 expression in GBM, highlighting the importance of TAM kinase signaling in GBM tumorigenesis and/or therapy resistance and providing strong rationale for targeting these pathways in the clinic. All three GBM cell lines exhibited dose dependent reductions in cell number and colony formation (>90% at 200nM) after treatment with UNC2025. Cell cycle analysis demonstrated accumulation of cells in the G2/M phase and development of polyploidy. After extended exposure, 60–80% of cells underwent apoptosis. The majority of surviving cells (65–95%) were senescent and did not recover after drug removal. Thus, UNC2025 mediates anti-tumor activity in GBM by multiple mechanisms. Conclusions The findings described here provide further evidence of oncogenic roles for MERTK in GBM, demonstrate the

  4. Extracellular vesicles from malignant effusions induce tumor cell migration: inhibitory effect of LMWH tinzaparin.

    PubMed

    Gamperl, Hans; Plattfaut, Corinna; Freund, Annika; Quecke, Tabea; Theophil, Friederike; Gieseler, Frank

    2016-10-01

    Elevated levels of extracellular vesicles (EVs) have been correlated with inflammatory diseases as well as progressive and metastatic cancer. By presenting tissue factor (TF) on their membrane surface, cellular microparticles (MPs) activate both the coagulation system and cell-signaling pathways such as the PAR/ERK pathway. We have shown before that malignant effusions are a rich source of tumor cell-derived EVs. Here, we used EVs from malignant effusions from three different patients after serial low-speed centrifugation steps as recommended by the ISTH (lsEV). Significant migration of human pancreatic carcinoma cells could be induced by lsEVs and was effectively inhibited by pre-incubation with tinzaparin, a low-molecular-weight heparin. Tinzaparin induced tissue factor pathway inhibitor (TFPI) release from tumor cells, and recombinant TFPI inhibited EV-induced tumor cell migration. EVs also induced ERK phosphorylation, whereas inhibitors of PAR2 and ERK suppressed EV-induced tumor cell migration. LsEVs have been characterized by high-resolution flow cytometry and, after elimination of smaller vesicles including exosomes, by further high-speed centrifugation (hsEV). The remaining population consisting primarily of MPs is indeed the main migration-inducing population with tenase activity. Compared to other LMWHs, tinzaparin is suggested to have high potency to induce TFPI release from epithelial cells. The migration-inhibitory effect of TFPI and the interruption of tumor cell migration by inhibitors of PAR2 and ERK suggest that lsEVs induce tumor cell migration by activating the PAR2 signaling pathway. Tinzaparin might inhibit this process at least partly by inducing the release of TFPI from tumor cells, which blocks PAR-activating TF complexes. The clinical relevance of the results is discussed.

  5. Transmission of endoplasmic reticulum stress and pro-inflammation from tumor cells to myeloid cells

    PubMed Central

    Mahadevan, Navin R.; Rodvold, Jeffrey; Sepulveda, Homero; Rossi, Steven; Drew, Angela F.; Zanetti, Maurizio

    2011-01-01

    Metabolic, infectious, and tumor cell-intrinsic noxae can all evoke the endoplasmic reticulum (ER) stress response in tumor cells, which is critical for tumor cell growth and cancer progression. Evidence exists that the ER stress response can drive a proinflammatory program in tumor cells and macrophages but, to our knowledge, a role for the tumor ER stress response in influencing macrophages and inflammation in the tumor microenvironment has not been suggested. Here we show that macrophages cultured in conditioned medium from ER-stressed tumor cells become activated, and themselves undergo ER stress with the up-regulation of Grp78, Gadd34, Chop, and Xbp-1 splicing, suggesting a general activation of the ER stress-signaling pathways. Furthermore, these macrophages recapitulate, amplify and expand the proinflammatory response of tumor cells. We term this phenomenon “transmissible” ER stress. Although neither Toll-like receptor (TLR)2 nor interleukin 6 receptor (IL6R) signaling is involved, a reduction was observed in the transmission of ER stress to TLR4 KO macrophages, consistent with the fact that a second signal through TLR4 combined with exposure to tumor ER stress-conditioned medium results in a faster ER stress response and an enhancement of proinflammatory cytokine production in macrophages. The injection of tumor ER stress-conditioned medium into WT mice elicited a generalized ER stress response in the liver. We suggest that transmissible ER stress is a mechanism through which tumor cells can control myeloid cells by directing them toward a proinflammatory phenotype, thus facilitating tumor progression. PMID:21464300

  6. Differential arrest and adhesion of tumor cells and microbeads in the microvasculature.

    PubMed

    Guo, Peng; Cai, Bin; Lei, Ming; Liu, Yang; Fu, Bingmei M

    2014-06-01

    To investigate the mechanical mechanisms behind tumor cell arrest in the microvasculature, we injected fluorescently labeled human breast carcinoma cells or similarly sized rigid beads into the systemic circulation of a rat. Their arrest patterns in the microvasculature of mesentery were recorded and quantified. We found that 93% of rigid beads were arrested either at arteriole-capillary intersections or in capillaries. Only 3% were at the capillary-postcapillary venule intersections and in postcapillary venules. In contrast, most of the flexible tumor cells were either entrapped in capillaries or arrested at capillary or postcapillary venule-postcapillary venule intersections and in postcapillary venules. Only 12% of tumor cells were arrested at the arteriole-capillary intersections. The differential arrest and adhesion of tumor cells and microbeads in the microvasculature was confirmed by a χ(2) test (p < 0.001). These results demonstrate that mechanical trapping was responsible for almost all the arrest of beads and half the arrest of tumor cells. Based on the measured geometry and blood flow velocities at the intersections, we also performed a numerical simulation using commercial software (ANSYS CFX 12.01) to depict the detailed distribution profiles of the velocity, shear rate, and vorticity at the intersections where tumor cells preferred to arrest and adhere. Simulation results reveal the presence of localized vorticity and shear rate regions at the turning points of the microvessel intersections, implying that hemodynamic factors play an important role in tumor cell arrest in the microcirculation. Our study helps elucidate long-debated issues related to the dominant factors in early-stage tumor hematogenous metastasis.

  7. Extracellular vesicles from malignant effusions induce tumor cell migration: inhibitory effect of LMWH tinzaparin.

    PubMed

    Gamperl, Hans; Plattfaut, Corinna; Freund, Annika; Quecke, Tabea; Theophil, Friederike; Gieseler, Frank

    2016-10-01

    Elevated levels of extracellular vesicles (EVs) have been correlated with inflammatory diseases as well as progressive and metastatic cancer. By presenting tissue factor (TF) on their membrane surface, cellular microparticles (MPs) activate both the coagulation system and cell-signaling pathways such as the PAR/ERK pathway. We have shown before that malignant effusions are a rich source of tumor cell-derived EVs. Here, we used EVs from malignant effusions from three different patients after serial low-speed centrifugation steps as recommended by the ISTH (lsEV). Significant migration of human pancreatic carcinoma cells could be induced by lsEVs and was effectively inhibited by pre-incubation with tinzaparin, a low-molecular-weight heparin. Tinzaparin induced tissue factor pathway inhibitor (TFPI) release from tumor cells, and recombinant TFPI inhibited EV-induced tumor cell migration. EVs also induced ERK phosphorylation, whereas inhibitors of PAR2 and ERK suppressed EV-induced tumor cell migration. LsEVs have been characterized by high-resolution flow cytometry and, after elimination of smaller vesicles including exosomes, by further high-speed centrifugation (hsEV). The remaining population consisting primarily of MPs is indeed the main migration-inducing population with tenase activity. Compared to other LMWHs, tinzaparin is suggested to have high potency to induce TFPI release from epithelial cells. The migration-inhibitory effect of TFPI and the interruption of tumor cell migration by inhibitors of PAR2 and ERK suggest that lsEVs induce tumor cell migration by activating the PAR2 signaling pathway. Tinzaparin might inhibit this process at least partly by inducing the release of TFPI from tumor cells, which blocks PAR-activating TF complexes. The clinical relevance of the results is discussed. PMID:27435911

  8. Ganglioside GD2 in reception and transduction of cell death signal in tumor cells

    PubMed Central

    2014-01-01

    Background Ganglioside GD2 is expressed on plasma membranes of various types of malignant cells. One of the most promising approaches for cancer immunotherapy is the treatment with monoclonal antibodies recognizing tumor-associated markers such as ganglioside GD2. It is considered that major mechanisms of anticancer activity of anti-GD2 antibodies are complement-dependent cytotoxicity and/or antibody-mediated cellular cytotoxicity. At the same time, several studies suggested that anti-GD2 antibodies are capable of direct induction of cell death of number of tumor cell lines, but it has not been investigated in details. In this study we investigated the functional role of ganglioside GD2 in the induction of cell death of multiple tumor cell lines by using GD2-specific monoclonal antibodies. Methods Expression of GD2 on different tumor cell lines was analyzed by flow cytometry using anti-GD2 antibodies. By using HPTLC followed by densitometric analysis we measured the amount of ganglioside GD2 in total ganglioside fractions isolated from tumor cell lines. An MTT assay was performed to assess viability of GD2-positive and -negative tumor cell lines treated with anti-GD2 mAbs. Cross-reactivity of anti-GD2 mAbs with other gangliosides or other surface molecules was investigated by ELISA and flow cytometry. Inhibition of GD2 expression was achieved by using of inhibitor for ganglioside synthesis PDMP and/or siRNA for GM2/GD2 and GD3 synthases. Results Anti-GD2 mAbs effectively induced non-classical cell death that combined features of both apoptosis and necrosis in GD2-positive tumor cells and did not affect GD2-negative tumors. Anti-GD2 mAbs directly induced cell death, which included alteration of mitochondrial membrane potential, induction of apoptotic volume decrease and cell membrane permeability. This cytotoxic effect was mediated exclusively by specific binding of anti-GD2 antibodies with ganglioside GD2 but not with other molecules. Moreover, the level of GD2

  9. Whole Tumor Cell Vaccine Adjuvants: Comparing IL-12 to IL-2 and IL-15.

    PubMed

    Sheikhi, Abdolkarim; Jafarzadeh, Abdollah; Kokhaei, Parviz; Hojjat-Farsangi, Mohammad

    2016-09-01

    Cancer immunotherapy (passive or active) involves treatments which promote the ability of the immune system to fight tumor cells. Several types of immunotherapeutic agents, such as monoclonal antibodies, immune checkpoint inhibitors, non-specific immunomodulatory agents, and cancer vaccines are currently under intensive investigation in preclinical and clinical trials. Cancer vaccines induce permanent activation of the immune system and may be considered the most promising method for cancer treatment, especially in combination with other agents of passive immunotherapy. Among various approaches to cancer vaccines, whole tumor cell vaccines have been attracting attention for several years. Despite their low to moderate clinical effects, these vaccines have numerous advantages. Their ability to generate immune responses against tumor-associated antigens reduces the possibility for tumor cells to escape and facilitates the development of "off-the-shelf" allogeneic tumor vaccines. Understanding the reciprocal interactions between tumor cells and leukocytes is a key to harness the full potential of whole cell vaccination. Cytokines are considered as potent immunomodulatory molecules which behave as adjuvants in whole tumor cell vaccines. Improved mechanistic understanding of key cytokines in tumor immunity will serve as a resource for rational design of whole cell cancer vaccines. Although there are several reports about the use of different immunostimulatory cytokines as adjuvants, interleukin (IL)-12 appears to have superior effects compared to other cytokines. This review describes the effects of IL-12 compared to other immunomodulatory cytokines, such as IL-2 and IL-15, and highlights its application in whole cell tumor vaccination. PMID:27671507

  10. Omega 3 fatty acids increase spontaneous release of cytosolic components from tumor cells

    SciTech Connect

    Jenski, L.J.; Sturdevant, L.K.; Ehringer, W.D.; Stillwell, W. )

    1991-05-01

    Mice fed menhaden (fish) oil or coconut oil-rich diets were inoculated intraperitoneally with a rapidly growing leukemia, T27A. After one week, the tumor cells were harvested, and 51Cr was used to label intracellular molecules. Spontaneous release of 51Cr was used as a measure of plasma membrane permeability. Compared to cells from mice fed coconut oil (rich in saturated fatty acids), tumor cells from mice fed menhaden oil (rich in long chain polyunsaturated omega 3 fatty acids) showed an increased level of spontaneous 51Cr release, which was exacerbated by increased temperature and reduced by extracellular protein. At physiological salt concentrations, the released 51Cr was detected in particles of approximately 2700 daltons. Enhanced permeability correlated with the incorporation of dietary (fish oil) omega 3 polyunsaturated fatty acids docosahexaenoic and eicosapentaenoic acid into the tumor cells. The results demonstrate that omega 3 fatty acids are incorporated into cellular constituents of tumor cells and change properties associated with the plasma membrane. This result suggests that dietary manipulation may be used to enhance tumor cell permeability and contribute to tumor eradication.

  11. Nifurtimox Is Effective Against Neural Tumor Cells and Is Synergistic with Buthionine Sulfoximine

    PubMed Central

    Du, Michael; Zhang, Linna; Scorsone, Kathleen A.; Woodfield, Sarah E.; Zage, Peter E.

    2016-01-01

    Children with aggressive neural tumors have poor survival rates and novel therapies are needed. Previous studies have identified nifurtimox and buthionine sulfoximine (BSO) as effective agents in children with neuroblastoma and medulloblastoma. We hypothesized that nifurtimox would be effective against other neural tumor cells and would be synergistic with BSO. We determined neural tumor cell viability before and after treatment with nifurtimox using MTT assays. Assays for DNA ladder formation and poly-ADP ribose polymerase (PARP) cleavage were performed to measure the induction of apoptosis after nifurtimox treatment. Inhibition of intracellular signaling was measured by Western blot analysis of treated and untreated cells. Tumor cells were then treated with combinations of nifurtimox and BSO and evaluated for viability using MTT assays. All neural tumor cell lines were sensitive to nifurtimox, and IC50 values ranged from approximately 20 to 210 μM. Nifurtimox treatment inhibited ERK phosphorylation and induced apoptosis in tumor cells. Furthermore, the combination of nifurtimox and BSO demonstrated significant synergistic efficacy in all tested cell lines. Additional preclinical and clinical studies of the combination of nifurtimox and BSO in patients with neural tumors are warranted. PMID:27282514

  12. Identification of thyroid tumor cell vulnerabilities through a siRNA-based functional screening

    PubMed Central

    Cetti, Elena; Fraietta, Ivan; Todoerti, Katia; Miranda, Claudia; Mazzoni, Mara; Re, Claudia; Colombo, Riccardo; Ukmar, Giorgio; Camisasca, Stefano; Pagliardini, Sonia; Pierotti, Marco A.; Neri, Antonino; Galvani, Arturo; Greco, Angela

    2015-01-01

    The incidence of thyroid carcinoma is rapidly increasing. Although generally associated with good prognosis, a fraction of thyroid tumors are not cured by standard therapy and progress to aggressive forms for which no effective treatments are currently available. In order to identify novel therapeutic targets for thyroid carcinoma, we focused on the discovery of genes essential for sustaining the oncogenic phenotype of thyroid tumor cells, but not required to the same degree for the viability of normal cells (non-oncogene addiction paradigm). We screened a siRNA oligonucleotide library targeting the human druggable genome in thyroid cancer BCPAP cell line in comparison with immortalized normal human thyrocytes (Nthy-ori 3–1). We identified a panel of hit genes whose silencing interferes with the growth of tumor cells, while sparing that of normal ones. Further analysis of three selected hit genes, namely Cyclin D1, MASTL and COPZ1, showed that they represent common vulnerabilities for thyroid tumor cells, as their inhibition reduced the viability of several thyroid tumor cell lines, regardless the histotype or oncogenic lesion. This work identified non-oncogenes essential for sustaining the phenotype of thyroid tumor cells, but not of normal cells, thus suggesting that they might represent promising targets for new therapeutic strategies. PMID:26431489

  13. Targeting Mitochondrial Function to Treat Quiescent Tumor Cells in Solid Tumors

    PubMed Central

    Zhang, Xiaonan; de Milito, Angelo; Olofsson, Maria Hägg; Gullbo, Joachim; D’Arcy, Padraig; Linder, Stig

    2015-01-01

    The disorganized nature of tumor vasculature results in the generation of microenvironments characterized by nutrient starvation, hypoxia and accumulation of acidic metabolites. Tumor cell populations in such areas are often slowly proliferating and thus refractory to chemotherapeutical drugs that are dependent on an active cell cycle. There is an urgent need for alternative therapeutic interventions that circumvent growth dependency. The screening of drug libraries using multicellular tumor spheroids (MCTS) or glucose-starved tumor cells has led to the identification of several compounds with promising therapeutic potential and that display activity on quiescent tumor cells. Interestingly, a common theme of these drug screens is the recurrent identification of agents that affect mitochondrial function. Such data suggest that, contrary to the classical Warburg view, tumor cells in nutritionally-compromised microenvironments are dependent on mitochondrial function for energy metabolism and survival. These findings suggest that mitochondria may represent an “Achilles heel” for the survival of slowly-proliferating tumor cells and suggest strategies for the development of therapy to target these cell populations. PMID:26580606

  14. 53BP1 foci as a marker of tumor cell radiosensitivity.

    PubMed

    Markova, E; Vasilyev, S; Belyaev, I

    2015-01-01

    Predicting tumor radiosensitivity has yet to be routinely integrated into radiotherapy. We analyzed the possibility to assess radiosensitivity of tumor cells based on endogenous and radiation-induced 53BP1 foci which are molecular markers of DNA double strand breaks (DSB). In eleven tumor cell lines of different origin, radiosensitivity was assessed by surviving cell fraction following irradiation with 2 Gy (SF2). 53BP1 foci were measured at 4 and 12 h post-irradiation by confocal laser microscopy and dedicated software. The correlation of 53BP1 foci and their post-irradiation kinetics with SF2 was assessed using Spearman rank test. The SF2 correlated with both excess of radiation-induced 53BP1 foci per cell at 4 h after irradiation and decay in number of 53BP1 foci from 4 to 12 h post-irradiation. The fraction of cells with multiple endogenous 53BP1 foci also correlated with SF2 of tumor cells. We conclude that the radiosensitivity of tumor cells can be predicted by kinetics of formation and decay of 53BP1 foci after irradiation. For the first time we report that the fraction of cells with multiple endogenous 53BP1 foci can be used as a marker of tumor cell radiosensitivity. PMID:26278144

  15. Mobilization of Viable Tumor Cells Into the Circulation During Radiation Therapy

    SciTech Connect

    Martin, Olga A.; Anderson, Robin L.; Russell, Prudence A.; Ashley Cox, R.; Ivashkevich, Alesia; Swierczak, Agnieszka; Doherty, Judy P.; Jacobs, Daphne H.M.; Smith, Jai; Siva, Shankar; Daly, Patricia E.; Ball, David L.; and others

    2014-02-01

    Purpose: To determine whether radiation therapy (RT) could mobilize viable tumor cells into the circulation of non-small cell lung cancer (NSCLC) patients. Methods and Materials: We enumerated circulating tumor cells (CTCs) by fluorescence microscopy of blood samples immunostained with conventional CTC markers. We measured their DNA damage levels using γ-H2AX, a biomarker for radiation-induced DNA double-strand breaks, either by fluorescence-activated cell sorting or by immunofluorescence microscopy. Results: Twenty-seven RT-treated NSCLC patients had blood samples analyzed by 1 or more methods. We identified increased CTC numbers after commencement of RT in 7 of 9 patients treated with palliative RT, and in 4 of 8 patients treated with curative-intent RT. Circulating tumor cells were also identified, singly and in clumps in large numbers, during RT by cytopathologic examination (in all 5 cases studied). Elevated γ-H2AX signal in post-RT blood samples signified the presence of CTCs derived from irradiated tumors. Blood taken after the commencement of RT contained tumor cells that proliferated extensively in vitro (in all 6 cases studied). Circulating tumor cells formed γ-H2AX foci in response to ex vivo irradiation, providing further evidence of their viability. Conclusions: Our findings provide a rationale for the development of strategies to reduce the concentration of viable CTCs by modulating RT fractionation or by coadministering systemic therapies.

  16. Morphological evidence of neutrophil-tumor cell phagocytosis (cannibalism) in human gastric adenocarcinomas.

    PubMed

    Caruso, R A; Muda, A O; Bersiga, A; Rigoli, L; Inferrera, C

    2002-01-01

    The phenomenon of neutrophil-tumor cell emperipolesis or phagocytosis has been documented by light microscopy in various human carcinomas, but little is known about the cellular pathological processes and the morphological changes involved. In an attempt to clarify the nature of this phenomenon, the authors' ultrastructural studies on the relationships among neutrophils and tumor cells in human gastric carcinomas are reviewed and analyzed. At the electron microscopy level, apoptotic neutrophils were found within vacuoles of adenocarcinoma cells in 2 cases. They showed either early apoptotic morphology with perinuclear chromatin aggregation but cytoplasm integrity or late apoptotic morphology with uniform, collapsed nucleus and tightly packed cytoplasmic granules. A light microscopy review of 200 cases of resected gastric carcinomas identified 22 cases (11%) that were characterized by neutrophil-tumor cell phagocytosis (cannibalism). TUNEL staining confirmed the presence of apoptotic neutrophils within the cytoplasm of the tumor cells. This study provides light and electron microscopic evidence of apoptotic neutrophils phagocytosed by gastric adenocarcinoma cells. The morphological features of neutrophil-tumor cell phagocytosis (cannibalism) would suggest a particular mechanism of tumor-immune escape in human gastric carcinoma. PMID:12396242

  17. Recognition of tumor cells by Dectin-1 orchestrates innate immune cells for anti-tumor responses

    PubMed Central

    Chiba, Shiho; Ikushima, Hiroaki; Ueki, Hiroshi; Yanai, Hideyuki; Kimura, Yoshitaka; Hangai, Sho; Nishio, Junko; Negishi, Hideo; Tamura, Tomohiko; Saijo, Shinobu; Iwakura, Yoichiro; Taniguchi, Tadatsugu

    2014-01-01

    The eradication of tumor cells requires communication to and signaling by cells of the immune system. Natural killer (NK) cells are essential tumor-killing effector cells of the innate immune system; however, little is known about whether or how other immune cells recognize tumor cells to assist NK cells. Here, we show that the innate immune receptor Dectin-1 expressed on dendritic cells and macrophages is critical to NK-mediated killing of tumor cells that express N-glycan structures at high levels. Receptor recognition of these tumor cells causes the activation of the IRF5 transcription factor and downstream gene induction for the full-blown tumoricidal activity of NK cells. Consistent with this, we show exacerbated in vivo tumor growth in mice genetically deficient in either Dectin-1 or IRF5. The critical contribution of Dectin-1 in the recognition of and signaling by tumor cells may offer new insight into the anti-tumor immune system with therapeutic implications. DOI: http://dx.doi.org/10.7554/eLife.04177.001 PMID:25149452

  18. The Effects of Nanotexturing Microfluidic Platforms to Isolate Brain Tumor Cells

    NASA Astrophysics Data System (ADS)

    Islam, Muhymin; Sajid, Adeel; Kim, Young-Tae; Iqbal, Samir M.

    2015-03-01

    Detection of tumor cells in the early stages of disease requires sensitive and selective approaches. Nanotextured polydimethylsiloxane (PDMS) substrates were implemented to detect metastatic human glioblastoma (hGBM) cells. RNA aptamers that were specific to epidermal growth factor receptors (EGFR) were used to functionalize the substrates. EGFR is known to be overexpressed on many cancer cells including hGBM. Nanotextured PDMS was prepared by micro reactive ion etching. PDMS surfaces became hydrophilic uponnanotexturing. Nanotextured substrates were incubated in tumor cell solution and density of captured cells was determined. Nanotextured PDMS provided >300% cell capture compared to plain PDMS due to increased effective surface area of roughened substrates at nanoscale as well as mire focal points for cell adhesion. Next, aptamer functionalized nanotextured PDMS was incorporated in microfluidic device to detect tumor cells at different flow velocities. The shear stress introduced by the flow pressure and heterogeneity of the EGFR overexpression on cell membranes of the tumor cells had significant impact on the cell capture efficiency of aptamer anchored nanotextured microfluidic devices. Eventually tumor cells were detected from the mixture of white blood cells at an efficiency of 73% using the microfluidic device. The interplay of binding energies and surface energies was major factor in this system. Support Acknowledged from NSF through ECCS-1407990.

  19. sup 51 Cr loss and lactate dehydrogenase (LDH) release in irradiated human tumor cells

    SciTech Connect

    Ts'ao, C.; Molteni, A.; Hinz, J. )

    1991-03-11

    Much of what is known about tumor cell radiosensitivity in vitro derives from the colony formation assay. Other endpoints of cytotoxicity in irradiated tumor cells are rarely examined. The purpose of this study was to determine whether loss of {sup 51}Cr from prelabeled cells and release of LDH could be used to quantify radiation injury in two cultured human tumor cell lines: a prostate carcinoma and a melanoma. Bovine aortic endothelial cells (EC) known to release {sup 51}Cr and LDH following irradiation, were cotested. Radioactivity and LDH activity in the culture medium were determined after 0-40 Gy of {sup 60}CO {gamma} rays. Proliferation of irradiated tumor cells was also studied. EC exhibited a time- and radiation dose-dependent increase in {sup 51}Cr and LDH release. Both tumor cell lines showed a time-dependent increase in {sup 51}Cr release, but this baseline release was not elevated after irradiation. LDH release from the prostate cancer cell line was observed within 8 hr after 40 Gy, and at 48 hr by 10 Gy. Irradiated melanoma cells, in contrast, never release excess LDH into the culture medium. Melanoma cells continued to proliferate after 10 Gy, while proliferation of prostate cancer cells was totally arrested by this dose of exposure. While {sup 51}Cr loss and LDH release appear to be sensitive indicators of radiation-induced damage in EC, they have limited value in the assessment of radiation-induced cytotoxicity in human prostate cancer and melanoma cells.

  20. Tumor cells prevent mouse dendritic cell maturation induced by TLR ligands.

    PubMed

    Idoyaga, Juliana; Moreno, José; Bonifaz, Laura

    2007-08-01

    Tumor cells can evade the immune system through several mechanisms, one of which is to block DC maturation. It has been suggested that signaling via Toll-like receptors (TLR) may be involved in the induction of prophylactic anti-cancer immunity and in the treatment of established tumors. In the present study we found that high numbers of tumor cells interfere with BMDC activation induced by the TLR ligands LPS and poly IC. Tumor cells blocked TLR3- and TLR4-mediated induction of MHCII and the co-stimulatory molecules CD40 and CD86, as well as the cytokines IL-12, TNF-alpha and IL-6. Importantly, tumor cells induced inhibitory molecules (B7-DC, B7-H1 and CD80) on spleen DC in vivo and on BMDC, even in the presence of TLR ligands. Moreover, after a long exposure with tumor cells, purified BMDC were unable to respond to a second challenge with TLR ligands. The failure of tumor exposed-BMDC to express co-stimulatory molecules and cytokines in the presence of TLR ligands has implications for the future development of DC-based cancer immune therapies using TLR ligands as adjuvants for the activation of DC.

  1. Identification of thyroid tumor cell vulnerabilities through a siRNA-based functional screening.

    PubMed

    Anania, Maria; Gasparri, Fabio; Cetti, Elena; Fraietta, Ivan; Todoerti, Katia; Miranda, Claudia; Mazzoni, Mara; Re, Claudia; Colombo, Riccardo; Ukmar, Giorgio; Camisasca, Stefano; Pagliardini, Sonia; Pierotti, Marco; Neri, Antonino; Galvani, Arturo; Greco, Angela

    2015-10-27

    The incidence of thyroid carcinoma is rapidly increasing. Although generally associated with good prognosis, a fraction of thyroid tumors are not cured by standard therapy and progress to aggressive forms for which no effective treatments are currently available. In order to identify novel therapeutic targets for thyroid carcinoma, we focused on the discovery of genes essential for sustaining the oncogenic phenotype of thyroid tumor cells, but not required to the same degree for the viability of normal cells (non-oncogene addiction paradigm). We screened a siRNA oligonucleotide library targeting the human druggable genome in thyroid cancer BCPAP cell line in comparison with immortalized normal human thyrocytes (Nthy-ori 3-1). We identified a panel of hit genes whose silencing interferes with the growth of tumor cells, while sparing that of normal ones. Further analysis of three selected hit genes, namely Cyclin D1, MASTL and COPZ1, showed that they represent common vulnerabilities for thyroid tumor cells, as their inhibition reduced the viability of several thyroid tumor cell lines, regardless the histotype or oncogenic lesion. This work identified non-oncogenes essential for sustaining the phenotype of thyroid tumor cells, but not of normal cells, thus suggesting that they might represent promising targets for new therapeutic strategies. PMID:26431489

  2. Impact of polyploidy on fertility variation of Mediterranean Arundo L. (Poaceae).

    PubMed

    Hardion, Laurent; Verlaque, Régine; Rosato, Marcela; Rosselló, Josep A; Vila, Bruno

    2015-05-01

    Failure of seed production in the genus Arundo L. (Poaceae) is often attributed to polyploidy. This study tested the impact of two ploidy levels (2n=12 and 18x) on the fertility of four Mediterranean Arundo. Viable pollen was screened from its production to its germination, and seed occurrence was monitored in admixture or isolated conditions. In addition, insights on restructuration of polyploid genomes were analysed using molecular cytogenetics. Our results show that high ploidy levels do not automatically induce failure of sexual reproduction. The two ploidy levels are able to produce viable pollen and seed set depending on species and cultural conditions. The sterility of A. micrantha (2n=12x) and A. donax (2n=18x) is due to the early failures of gametogenesis steps. For 18x cytotypes of A. donaciformis and A. plinii, seed absence for isolated genotype vs. seed production in admixed culture support their auto-incompatibility. PMID:25908118

  3. Cip/Kip cyclin-dependent protein kinase inhibitors and the road to polyploidy

    PubMed Central

    Ullah, Zakir; Lee, Chrissie Y; DePamphilis, Melvin L

    2009-01-01

    Cyclin-dependent kinases (CDKs) play a central role in the orderly transition from one phase of the eukaryotic mitotic cell division cycle to the next. In this context, p27Kip1 (one of the CIP/KIP family of CDK specific inhibitors in mammals) or its functional analogue in other eukarya prevents a premature transition from G1 to S-phase. Recent studies have revealed that expression of a second member of this family, p57Kip2, is induced as trophoblast stem (TS) cells differentiate into trophoblast giant (TG) cells. p57 then inhibits CDK1 activity, an enzyme essential for initiating mitosis, thereby triggering genome endoreduplication (multiple S-phases without an intervening mitosis). Expression of p21Cip1, the third member of this family, is also induced in during differentiation of TS cells into TG cells where it appears to play a role in suppressing the DNA damage response pathway. Given the fact that p21 and p57 are unique to mammals, the question arises as to whether one or both of these proteins are responsible for the induction and maintenance of polyploidy during mammalian development. PMID:19490616

  4. The “virgin birth”, polyploidy, and the origin of cancer

    PubMed Central

    Erenpreisa, Jekaterina; Salmina, Kristine; Huna, Anda; Jackson, Thomas R.; Vazquez-Martin, Alejandro; Cragg, Mark S.

    2015-01-01

    Recently, it has become clear that the complexity of cancer biology cannot fully be explained by somatic mutation and clonal selection. Meanwhile, data have accumulated on how cancer stem cells or stemloids bestow immortality on tumour cells and how reversible polyploidy is involved. Most recently, single polyploid tumour cells were shown capable of forming spheroids, releasing EMT-like descendents and inducing tumours in vivo. These data refocus attention on the centuries-old embryological theory of cancer. This review attempts to reconcile seemingly conflicting data by viewing cancer as a pre-programmed phylogenetic life-cycle-like process. This cycle is apparently initiated by a meiosis-like process and driven as an alternative to accelerated senescence at the DNA damage checkpoint, followed by an asexual syngamy event and endopolyploid-type embryonal cleavage to provide germ-cell-like (EMT) cells. This cycle is augmented by genotoxic treatments, explaining why chemotherapy is rarely curative and drives resistance. The logical outcome of this viewpoint is that alternative treatments may be more efficacious - either those that suppress the endopolyploidy-associated ‘life cycle’ or, those that cause reversion of embryonal malignant cells into benign counterparts. Targets for these opposing strategies are components of the same molecular pathways and interact with regulators of accelerated senescence. PMID:25821840

  5. The flavonoid eupatorin inactivates the mitotic checkpoint leading to polyploidy and apoptosis.

    PubMed

    Salmela, Anna-Leena; Pouwels, Jeroen; Kukkonen-Macchi, Anu; Waris, Sinikka; Toivonen, Pauliina; Jaakkola, Kimmo; Mäki-Jouppila, Jenni; Kallio, Lila; Kallio, Marko J

    2012-03-10

    The spindle assembly checkpoint (SAC) is a conserved mechanism that ensures the fidelity of chromosome distribution in mitosis by preventing anaphase onset until the correct bipolar microtubule-kinetochore attachments are formed. Errors in SAC function may contribute to tumorigenesis by inducing numerical chromosome anomalies (aneuploidy). On the other hand, total disruption of SAC can lead to massive genomic imbalance followed by cell death, a phenomena that has therapeutic potency. We performed a cell-based high-throughput screen with a compound library of 2000 bioactives for novel SAC inhibitors and discovered a plant-derived phenolic compound eupatorin (3',5-dihydroxy-4',6,7-trimethoxyflavone) as an anti-mitotic flavonoid. The premature override of the microtubule drug-imposed mitotic arrest by eupatorin is dependent on microtubule-kinetochore attachments but not interkinetochore tension. Aurora B kinase activity, which is essential for maintenance of normal SAC signaling, is diminished by eupatorin in cells and in vitro providing a mechanistic explanation for the observed forced mitotic exit. Eupatorin likely has additional targets since eupatorin treatment of pre-mitotic cells causes spindle anomalies triggering a transient M phase delay followed by impaired cytokinesis and polyploidy. Finally, eupatorin potently induces apoptosis in multiple cancer cell lines and suppresses cancer cell proliferation in organotypic 3D cell culture model.

  6. The flavonoid eupatorin inactivates the mitotic checkpoint leading to polyploidy and apoptosis

    SciTech Connect

    Salmela, Anna-Leena; Pouwels, Jeroen; Kukkonen-Macchi, Anu; Waris, Sinikka; Toivonen, Pauliina; Jaakkola, Kimmo; Maeki-Jouppila, Jenni; Kallio, Lila; Kallio, Marko J.

    2012-03-10

    The spindle assembly checkpoint (SAC) is a conserved mechanism that ensures the fidelity of chromosome distribution in mitosis by preventing anaphase onset until the correct bipolar microtubule-kinetochore attachments are formed. Errors in SAC function may contribute to tumorigenesis by inducing numerical chromosome anomalies (aneuploidy). On the other hand, total disruption of SAC can lead to massive genomic imbalance followed by cell death, a phenomena that has therapeutic potency. We performed a cell-based high-throughput screen with a compound library of 2000 bioactives for novel SAC inhibitors and discovered a plant-derived phenolic compound eupatorin (3 Prime ,5-dihydroxy-4 Prime ,6,7-trimethoxyflavone) as an anti-mitotic flavonoid. The premature override of the microtubule drug-imposed mitotic arrest by eupatorin is dependent on microtubule-kinetochore attachments but not interkinetochore tension. Aurora B kinase activity, which is essential for maintenance of normal SAC signaling, is diminished by eupatorin in cells and in vitro providing a mechanistic explanation for the observed forced mitotic exit. Eupatorin likely has additional targets since eupatorin treatment of pre-mitotic cells causes spindle anomalies triggering a transient M phase delay followed by impaired cytokinesis and polyploidy. Finally, eupatorin potently induces apoptosis in multiple cancer cell lines and suppresses cancer cell proliferation in organotypic 3D cell culture model.

  7. The association between polyploidy and clonal reproduction in diploid and tetraploid Chamerion angustifolium.

    PubMed

    Baldwin, Sarah J; Husband, Brian C

    2013-04-01

    Clonal reproduction is associated with the incidence of polyploidy in flowering plants. This pattern may arise through selection for increased clonality in polyploids compared to diploids to reduce mixed-ploidy mating. Here, we test whether clonal reproduction is greater in tetraploid than diploid populations of the mixed-ploidy plant, Chamerion angustifolium, through an analysis of the size and spatial distribution of clones in natural populations using AFLP genotyping and a comparison of root bud production in a greenhouse study. Natural tetraploid populations (N = 5) had significantly more AFLP genotypes (x¯ = 10.8) than diploid populations (x¯ = 6.0). Tetraploid populations tended to have fewer ramets per genotype and fewer genotypes with >1 ramet. In a spatial autocorrelation analysis, ramets within genotypes were more spatially aggregated in diploid populations than in tetraploid populations. In the greenhouse, tetraploids allocated 90.4% more dry mass to root buds than diploids, but tetraploids produced no more root buds and 44% fewer root buds per unit root mass than diploids. Our results indicate that clonal reproduction is significant in most populations, but tetraploid populations are not more clonal than diploids, nor are their clones more spatially aggregated. As a result, tetraploids may be less sheltered from mixed-ploidy mating and diploids more exposed to inbreeding, the balance of which could influence the establishment of tetraploids in diploid populations. PMID:23432094

  8. Polyploidy can Confer Superiority to West African Acacia senegal (L.) Willd. Trees

    PubMed Central

    Diallo, Adja M.; Nielsen, Lene R.; Kjær, Erik D.; Petersen, Karen K.; Ræbild, Anders

    2016-01-01

    Polyploidy is a common phenomenon in the evolution of angiosperms. It has been suggested that polyploids manage harsh environments better than their diploid relatives but empirical data supporting this hypothesis are scarce, especially for trees. Using microsatellite markers and flow cytometry, we examine the frequency of polyploids and diploids in a progeny trial testing four different populations of Acacia senegal, a species native to sub-Saharan regions of Africa. We compare growth between cytotypes and test whether polyploid seedlings grow better than diploids. Our results show that polyploids coexist with diploids in highly variable proportions among populations in Senegal. Acacia senegal genotypes were predominantly diploid and tetraploid, but triploid, pentaploid, hexaploid, and octaploid forms were also found. We find that polyploids show faster growth than diploids under our test conditions: in an 18 years old field trial, polyploid superiority was estimated to be 17% in trunk diameter and 9% in height while in a growth chamber experiment, polyploids grew 28% taller, but only after being exposed to drought stress. The results suggest that polyploid A. senegal can have an adaptive advantage in some regions of Africa. PMID:27379120

  9. Intraspecific and interspecific polyploidy of Brazilian species of the genus Inga (Leguminosae: Mimosoideae).

    PubMed

    Figueiredo, M F; Bruno, R L A; Barros e Silva, A E; Nascimento, S; Oliveira, I G; Felix, L P

    2014-04-29

    We investigated the karyotypes of 13 species of six sections of the genus Inga (Leguminosae-Mimosoideae) from Brazil. We used conventional Giemsa staining to identify numerical chromosomal variations and looked for karyotypic evolutionary patterns. The karyotypes generally had small chromosomes, varying from metacentric to submetacentric, with a basic number x=13. Nine of the species showed 2n=2x=26 (I. thibaudiana, I. cayennensis, I. ingoides, I. edulis, I. vera, I. subnuda, I. striata, I. bollandii, and Inga sp), while 2n=4x=52 was seen in a population of Inga cylindrical and of I. capitata, and in five populations of I. laurina. Additionally, 2n=8x=104 was observed in a population of I. cayennensis. Eight of these counts were new, while the counts of 2n=52 for I. laurina and 2n=26 for I. marginata, I. vera, I. subnuda, and I. edulis confirmed previous studies. We did not find cytological stability among the sections studied, with occurrence of significant intra- and inter-specific numerical variations. We conclude that polyploidy has played a significant role in karyotypic evolution in this group and that it occurred independently in several sections of the genus.

  10. Regulation of DNA replication and chromosomal polyploidy by the MLL-WDR5-RBBP5 methyltransferases

    PubMed Central

    Lu, Fei; Wu, Xiaojun; Yin, Feng; Chia-Fang Lee, Christina; Yu, Min; Mihaylov, Ivailo S.; Yu, Jiekai; Sun, Hong

    2016-01-01

    ABSTRACT DNA replication licensing occurs on chromatin, but how the chromatin template is regulated for replication remains mostly unclear. Here, we have analyzed the requirement of histone methyltransferases for a specific type of replication: the DNA re-replication induced by the downregulation of either Geminin, an inhibitor of replication licensing protein CDT1, or the CRL4CDT2 ubiquitin E3 ligase. We found that siRNA-mediated reduction of essential components of the MLL-WDR5-RBBP5 methyltransferase complexes including WDR5 or RBBP5, which transfer methyl groups to histone H3 at K4 (H3K4), suppressed DNA re-replication and chromosomal polyploidy. Reduction of WDR5/RBBP5 also prevented the activation of H2AX checkpoint caused by re-replication, but not by ultraviolet or X-ray irradiation; and the components of MLL complexes co-localized with the origin recognition complex (ORC) and MCM2-7 replicative helicase complexes at replication origins to control the levels of methylated H3K4. Downregulation of WDR5 or RBBP5 reduced the methylated H3K4 and suppressed the recruitment of MCM2-7 complexes onto replication origins. Our studies indicate that the MLL complexes and H3K4 methylation are required for DNA replication but not for DNA damage repair. PMID:27744293

  11. Polyploidy can Confer Superiority to West African Acacia senegal (L.) Willd. Trees.

    PubMed

    Diallo, Adja M; Nielsen, Lene R; Kjær, Erik D; Petersen, Karen K; Ræbild, Anders

    2016-01-01

    Polyploidy is a common phenomenon in the evolution of angiosperms. It has been suggested that polyploids manage harsh environments better than their diploid relatives but empirical data supporting this hypothesis are scarce, especially for trees. Using microsatellite markers and flow cytometry, we examine the frequency of polyploids and diploids in a progeny trial testing four different populations of Acacia senegal, a species native to sub-Saharan regions of Africa. We compare growth between cytotypes and test whether polyploid seedlings grow better than diploids. Our results show that polyploids coexist with diploids in highly variable proportions among populations in Senegal. Acacia senegal genotypes were predominantly diploid and tetraploid, but triploid, pentaploid, hexaploid, and octaploid forms were also found. We find that polyploids show faster growth than diploids under our test conditions: in an 18 years old field trial, polyploid superiority was estimated to be 17% in trunk diameter and 9% in height while in a growth chamber experiment, polyploids grew 28% taller, but only after being exposed to drought stress. The results suggest that polyploid A. senegal can have an adaptive advantage in some regions of Africa. PMID:27379120

  12. Vita-Assay™ Method of Enrichment and Identification of Circulating Cancer Cells/Circulating Tumor Cells (CTCs).

    PubMed

    Tulley, Shaun; Zhao, Qiang; Dong, Huan; Pearl, Michael L; Chen, Wen-Tien

    2016-01-01

    The ability to capture, enrich, and propagate circulating cancer cells/circulating tumor cells (CTCs) for downstream analyses such as ex vivo drug-sensitivity testing of short-term cultures of CTCs, single cell sorting of CTCs by fluorescence activated cell sorting (FACS), animal injection tumor and/or metastasis formation studies, next generation sequencing (NGS), gene expression profiling, gene copy number determination, and epigenomic analyses is of high priority and of immense importance to both the basic research and translational/clinical research communities. Vitatex Inc.'s functional cell separation technology, constructed as Vita-Assay™ (AG6W, AN6W, AR6W) culture plates, is based on the preferential adhesion of invasive rare blood cells of tissue origin to a tissue or tumor microenvironment mimic-the so-called cell adhesion matrix (CAM), which has a demonstrated ability to enrich viable CTCs from blood up to one-million fold.The CAM-scaffold allows for the functional capture and identification of invasive CTCs (iCTCs) including invasive tumor progenitor (TP) cells from cancer-patients' blood. CAM-captured CTCs are capable of ingesting the CAM (CAM+) itself. Green and red fluorescent versions of Vita-Assay™ (AG6W and AR6W) allow for direct visualization of CAM-uptake by cancer cells. Vita-Assay™ CAM-enrichment has allowed for sensitive multiplex flow cytometric and microscopic detection of iCTCs from patients with cancers of the breast, ovary, prostate, pancreas, colorectum, and lung; it has also been successfully utilized for ex vivo drug-sensitivity testing of ovarian-cancer patient CTCs. The CAM enrichment method is equally suitable for the separation of iCTCs and TP cells in ascites and pleural fluid.

  13. An epigenetically distinct breast cancer cell subpopulation promotes collective invasion.

    PubMed

    Westcott, Jill M; Prechtl, Amanda M; Maine, Erin A; Dang, Tuyen T; Esparza, Matthew A; Sun, Han; Zhou, Yunyun; Xie, Yang; Pearson, Gray W

    2015-05-01

    Tumor cells can engage in a process called collective invasion, in which cohesive groups of cells invade through interstitial tissue. Here, we identified an epigenetically distinct subpopulation of breast tumor cells that have an enhanced capacity to collectively invade. Analysis of spheroid invasion in an organotypic culture system revealed that these "trailblazer" cells are capable of initiating collective invasion and promote non-trailblazer cell invasion, indicating a commensal relationship among subpopulations within heterogenous tumors. Canonical mesenchymal markers were not sufficient to distinguish trailblazer cells from non-trailblazer cells, suggesting that defining the molecular underpinnings of the trailblazer phenotype could reveal collective invasion-specific mechanisms. Functional analysis determined that DOCK10, ITGA11, DAB2, PDFGRA, VASN, PPAP2B, and LPAR1 are highly expressed in trailblazer cells and required to initiate collective invasion, with DOCK10 essential for metastasis. In patients with triple-negative breast cancer, expression of these 7 genes correlated with poor outcome. Together, our results indicate that spontaneous conversion of the epigenetic state in a subpopulation of cells can promote a transition from in situ to invasive growth through induction of a cooperative form of collective invasion and suggest that therapeutic inhibition of trailblazer cell invasion may help prevent metastasis.

  14. An epigenetically distinct breast cancer cell subpopulation promotes collective invasion

    PubMed Central

    Westcott, Jill M.; Prechtl, Amanda M.; Maine, Erin A.; Dang, Tuyen T.; Esparza, Matthew A.; Sun, Han; Zhou, Yunyun; Xie, Yang; Pearson, Gray W.

    2015-01-01

    Tumor cells can engage in a process called collective invasion, in which cohesive groups of cells invade through interstitial tissue. Here, we identified an epigenetically distinct subpopulation of breast tumor cells that have an enhanced capacity to collectively invade. Analysis of spher