Cancer Biology Commons^™

Tumor Cell-Organized Fibronectin Is Required To Maintain A Dormant Breast Cancer Population, Lauren E. Barney, Christopher L. Hall, Alyssa D. Schwartz, Akia N. Parks, Christopher Sparages, Sualyneth Galarza, Manu O. Platt, Arthur M. Mercurio, Shelly R. Peyton

Arthur M. Mercurio

Tumors can undergo long periods of dormancy, with cancer cells entering a largely quiescent, non-proliferative state before reactivation and outgrowth. For a patient, these post-remission tumors are often drug resistant and highly aggressive, resulting in poor prognosis. To understand the role of the extracellular matrix (ECM) in regulating tumor dormancy, we created an in vitro cell culture system that combines carefully controlled ECM substrates with nutrient deprivation to observe entrance into and exit from dormancy with live imaging. We saw that cell populations capable of surviving entrance into long-term dormancy were heterogeneous, containing quiescent, cell cycle arrested, and actively proliferating …

Vegf/Neuropilin Signaling In Cancer Stem Cells, Arthur M. Mercurio

Arthur M. Mercurio

The function of vascular endothelial growth factor (VEGF) in cancer extends beyond angiogenesis and vascular permeability. Specifically, VEGF-mediated signaling occurs in tumor cells and this signaling contributes to key aspects of tumorigenesis including the self-renewal and survival of cancer stem cells (CSCs). In addition to VEGF receptor tyrosine kinases, the neuropilins (NRPs) are critical for mediating the effects of VEGF on CSCs, primarily because of their ability to impact the function of growth factor receptors and integrins. VEGF/NRP signaling can regulate the expression and function of key molecules that have been implicated in CSC function including Rho family guanosine triphosphatases …

Intracellular Signaling And Trafficking In Cancer: Role Of Rab5-Gtpase In Migration And Invasion Of Breast Cells, Nicole Porther

Nicole Porther

Metastasis is characterized pathologically by uncontrolled cell invasion, proliferation, migration and angiogenesis. Steroid hormones, such as estrogen, and growth factors, which include insulin growth factor I/II (IGF-1/IGF-2) therapy has been associated with most if not all of the features of metastasis. It has been determined that IGF-1 increases cell survival of cancer cells and potentiate the effect of E2 and other ligand growth factors on breast cancer cells. However not much information is available that comprehensively expounds on the roles of insulin growth factor receptor (IGFR) and Rab GTPases may play in breast cancer. The latter, Rab GTPases, are small …

Impact Of The C-Mybe308g Mutation On Mouse Myelopoiesis And Dendritic Cell Development, Peter Papathanasiou, Sawang Petvises, Ying-Ying Hey, Andrew C Perkins, Helen C O'Neill

Helen O'Neill

Booreana mice carrying the c-Myb308G point mutation were analyzed to determine changes in early hematopoiesis in the bone marrow and among mature cells in the periphery. This point mutation led to increased numbers of early hematopoietic stem and progenitor cells (HSPCs), with a subsequent reduction in the development of B cells, erythroid cells, and neutrophils, and increased numbers of myeloid cells and granulocytes. Myelopoiesis was further investigated by way of particular subsets affected. A specific question addressed whether booreana mice contained increased numbers of dendritic-like cells (L-DC subset) recently identified in the spleen, since L-DCs arise in vitro by direct …

Sumo-Targeted Ubiquitin Ligase (Stubl) Slx5 Regulates Proteolysis Of Centromeric Histone H3 Variant Cse4 And Prevents Its Mislocalization To Euchromatin, Kentaro Ohkuni, Yoshimitsu Takahashi, Alyona Flup, Josh La, Wei-Chun Au, Nagesh Pasupala, Ruben Levy-Meyers, Jack Warren, Alexander Strunnikov, Richard E. Baker, Oliver Kerscher, Kerry Bloom, Munira A. Basrai

Oliver Kerscher

Centromeric histone H3, CENP-ACse4, is essential for faithful chromosome segregation. Stringent regulation of cellular levels of CENP-ACse4 restricts its localization to centromeres. Mislocalization of CENP-ACse4 is associated with aneuploidy in yeast and flies and tumorigenesis in human cells; thus defining pathways that regulate CENP-A levels is critical for understanding how mislocalization of CENP-A contributes to aneuploidy in human cancers. Previous work in budding yeast shows that ubiquitination of overexpressed Cse4 by Psh1, an E3 ligase, partially contributes to proteolysis of Cse4. Here we provide the first evidence that Cse4 is sumoylated by E3 ligases Siz1 and Siz2 in vivo and …

P-Rex1 Promotes Resistance To Vegf/Vegfr-Targeted Therapy In Prostate Cancer, Hira Lal Goel, Bryan M. Pursell, Leonard D. Shultz, Dale L. Greiner, Rolf A. Brekken, Craig W. Vander Kooi, Arthur M. Mercurio

Arthur M. Mercurio

Autocrine VEGF signaling is critical for sustaining prostate and other cancer stem cells (CSCs), and it is a potential therapeutic target, but we observed that CSCs isolated from prostate tumors are resistant to anti-VEGF (bevacizumab) and anti-VEGFR (sunitinib) therapy. Intriguingly, resistance is mediated by VEGF/neuropilin signaling, which is not inhibited by bevacizumab and sunitinib, and it involves the induction of P-Rex1, a Rac GEF, and consequent Rac1-mediated ERK activation. This induction of P-Rex1 is dependent on Myc. CSCs isolated from the PTEN(pc-/-) transgenic model of prostate cancer exhibit Rac1-dependent resistance to bevacizumab. Rac1 inhibition or P-Rex1 downregulation increases the sensitivity …

Alcoholic Hepatitis Accelerates Early Hepatobiliary Cancer By Increasing Stemness And Mir-122-Mediated Hif-1alpha Activation, Aditya Ambade, Abhishek Satishchandran, Gyongyi Szabo

Gyongyi Szabo

Alcohol-related hepatocellular carcinoma (HCC) develops with advanced alcoholic liver disease and liver fibrosis. Using adult mice, we evaluate the effect of alcoholic steatohepatitis on early hepatobiliary carcinoma after initiation by diethyl-nitrosamine (DEN). Here we show that alcohol-fed DEN-injected mice have higher ALT and liver-to-body weight ratio compared to pair-fed DEN-injected mice. Alcohol feeding results in steatohepatitis indicated by increased pro-inflammatory cytokines and fibrotic genes. MRI and liver histology of alcohol+DEN mice shows hepatobiliary cysts, early hepatic neoplasia and increase in serum alpha-fetoprotein. Proliferation makers (BrdU, cyclin D1, p53) and cancer stem cell markers (CD133 and nanog) are significantly up-regulated in …

Identification And Validation Of The Potential Biomarker Insulin-Like Growth Factor Binding Protein Acid-Labile Subunit For Breast Cancer In African American Women, Padma P. Tadi Uppala, Carlos A. Garberoglio, Sharon Lum, Willie L. Davis, Michael Liebman, Keiji Oda, Utkarsh P. Patel

Padma Tadi Uppala

Erbeta Regulation Of Nf-Kb Activation In Prostate Cancer Is Mediated By Hif-1, Paul Mak, Jiarong Li, Sanjoy Samanta, Arthur M. Mercurio

Arthur M. Mercurio

We examined the regulation of NF-kappaB in prostate cancer by estrogen receptor beta (ERbeta) based on the inverse correlation between p65 and ERbeta expression that exists in prostate carcinomas and reports that ERbeta can inhibit NF-kappaB activation, although the mechanism is not known. We demonstrate that ERbeta functions as a gate-keeper for NF-kappaB p65 signaling by repressing its expression and nuclear translocation. ERbeta regulation of NF-kappaB signaling is mediated by HIF-1. Loss of ERbeta or hypoxia stabilizes HIF-1alpha, which we found to be a direct driver of IKKbeta transcription through a hypoxia response element present in the promoter of the …

Crosstalk Between Brca-Fanconi Anemia And Mismatch Repair Pathways Prevents Msh2-Dependent Aberrant Dna Damage Responses, Min Peng, Jenny X. Xie, Anna J. Ucher, Janet Stavnezer, Sharon B. Cantor

Janet M. Stavnezer

Several proteins in the BRCA-Fanconi anemia (FA) pathway, such as FANCJ, BRCA1, and FANCD2, interact with mismatch repair (MMR) pathway factors, but the significance of this link remains unknown. Unlike the BRCA-FA pathway, the MMR pathway is not essential for cells to survive toxic DNA interstrand crosslinks (ICLs), although MMR proteins bind ICLs and other DNA structures that form at stalled replication forks. We hypothesized that MMR proteins corrupt ICL repair in cells that lack crosstalk between BRCA-FA and MMR pathways. Here, we show that ICL sensitivity of cells lacking the interaction between FANCJ and the MMR protein MLH1 is …

Na/K-Atpase Mimetic Pnaktide Peptide Inhibits The Growth Of Human Cancer Cells, Zhichuan Li, Zhongbing Zhang, Joe X. Xie, Xin Li, Jiang Tian, Ting Cai, Hongaun Cui, Hanfei Ding, Joseph I. Shapiro Md, Zijian Xie

Zijian Xie

Cells contain a large pool of non-pumping Na/K-ATPase that participates in signal transduction. Here, we show that the expression of α1 Na/K-ATPase is significantly reduced in human prostate carcinoma as well as in several human cancer cell lines. This down-regulation impairs the ability of Na/K-ATPase to regulate Src-related signaling processes. Supplement of pNaKtide, a peptide derived from α1 Na/K-ATPase, reduces activities of Src and Src effectors. Consequently, these treatments stimulate apoptosis and inhibit growth in cultures of human cancer cells. Moreover, administration of pNaKtide inhibits angiogenesis and growth of tumor xenograft. Thus, the new findings demonstrate the in vivo effectiveness …

Na/K-Atpase Mimetic Pnaktide Peptide Inhibits The Growth Of Human Cancer Cells, Zhichuan Li, Zhongbing Zhang, Joe X. Xie, Xin Li, Jiang Tian, Ting Cai, Hongaun Cui, Hanfei Ding, Joseph I. Shapiro Md, Zijian Xie

Joseph I Shapiro MD

Cells contain a large pool of non-pumping Na/K-ATPase that participates in signal transduction. Here, we show that the expression of α1 Na/K-ATPase is significantly reduced in human prostate carcinoma as well as in several human cancer cell lines. This down-regulation impairs the ability of Na/K-ATPase to regulate Src-related signaling processes. Supplement of pNaKtide, a peptide derived from α1 Na/K-ATPase, reduces activities of Src and Src effectors. Consequently, these treatments stimulate apoptosis and inhibit growth in cultures of human cancer cells. Moreover, administration of pNaKtide inhibits angiogenesis and growth of tumor xenograft. Thus, the new findings demonstrate the in vivo effectiveness …

Prostate Tumorigenesis Induced By Pten Deletion Involves Estrogen Receptor Beta Repression, Paul Mak, Jianrong Li, Sanjoy Samanta, Cheng Chang, D. Joseph Jerry, Roger J. Davis, Irwin Leav, Arthur M. Mercurio

Arthur M. Mercurio

The role of ERbeta in prostate cancer is unclear, although loss of ERbeta is associated with aggressive disease. Given that mice deficient in ERbeta do not develop prostate cancer, we hypothesized that ERbeta loss occurs as a consequence of tumorigenesis caused by other oncogenic mechanisms and that its loss is necessary for tumorigenesis. In support of this hypothesis, we found that ERbeta is targeted for repression in prostate cancer caused by PTEN deletion and that loss of ERbeta is important for tumor formation. ERbeta transcription is repressed by BMI-1, which is induced by PTEN deletion and important for prostate tumorigenesis. …

A Laminin 511 Matrix Is Regulated By Taz And Functions As The Ligand For The Alpha6bbeta1 Integrin To Sustain Breast Cancer Stem Cells, Cheng Chang, Hira Lal Goel, Huijie Gao, Bryan M. Pursell, Leonard D. Shultz, Dale L. Greiner, Sulev Ingerpuu, Manuel Patarroyo, Shiliang Cao, Elgene Lim, Junhao Mao, Karen Kulju. Mckee, Peter D. Yurchenco, Arthur M. Mercurio

Arthur M. Mercurio

Understanding how the extracellular matrix impacts the function of cancer stem cells (CSCs) is a significant but poorly understood problem. We report that breast CSCs produce a laminin (LM) 511 matrix that promotes self-renewal and tumor initiation by engaging the alpha6Bbeta1 integrin and activating the Hippo transducer TAZ. Although TAZ is important for the function of breast CSCs, the mechanism is unknown. We observed that TAZ regulates the transcription of the alpha5 subunit of LM511 and the formation of a LM511 matrix. These data establish a positive feedback loop involving TAZ and LM511 that contributes to stemness in breast cancer.

Gene Expression Profiles Identify Features Common To Lobular And Ductal Premalignant Breast Lesions, Amy L. Roberts, D. Joseph Jerry, Kelly J. Gauger, Sallie S. Schneider, Giovanna M. Crisi, Grace Makari-Judson, Ashraf Khan, Karl Simin

Grace Makari-Judson MD

Premalignant lesions have been identified in both the ductal and lobular units of the breast epithelium. These lesions have a 4-fold increase in risk of progression to invasive breast cancer, but 80% will remain indolent. This may be due, in part, to the uncertainty of diagnoses as inter-observer reproducibility is poor. When treated with prophylactic hormone therapies blocking the estrogen receptor, up to 40% of women still develop tumors. Therefore the challenge is to develop diagnostic tests that identify the subset of high-risk lesions and provide appropriate prophylactic therapies. We undertook genome-wide expression studies to define sets of genes that …

The Nuclear Factor Of Activated T Cells (Nfat) Transcription Factor Nfatp (Nfatc2) Is A Repressor Of Chondrogenesis, Ann M. Ranger, Louis C. Gerstenfeld, Jinxi Wang, Tamiyo Kon, Hyunsu Bae, Ellen M. Gravallese, Melvin J. Glimcher, Laurie H. Glimcher

Ellen M. Gravallese

Nuclear factor of activated T cells (NFAT) transcription factors regulate gene expression in lymphocytes and control cardiac valve formation. Here, we report that NFATp regulates chondrogenesis in the adult animal. In mice lacking NFATp, resident cells in the extraarticular connective tissues spontaneously differentiate to cartilage. These cartilage cells progressively differentiate and the tissue undergoes endochondral ossification, recapitulating the development of endochondral bone. Proliferation of already existing articular cartilage cells also occurs in some older animals. At both sites, neoplastic changes in the cartilage cells occur. Consistent with these data, NFATp expression is regulated in mesenchymal stem cells induced to differentiate …

Introduction To Gene Enrichment Analysis Tools, Rolando Garcia-Milian

Rolando Garcia-Milian

Bioinformatics enrichment tools play an important role in identifying, annotating, and functionally analyzing large list of genes generated by high-throughput technologies (e.g. microarrary, RNA-seq, ChIP-chip). This workshop will provide an overview of the principle, type of enrichments, and the infrastructure of enrichment tools. By using concrete examples, it will also introduce some of the most popular tools for gene enrichment analysis such as DAVID, GSEA, and WebGestalt.

Nuclear Pore Component Nup98 Is A Potential Tumor Suppressor And Regulates Posttranscriptional Expression Of Select P53 Target Genes, Stephan Singer, Ruiying Zhao, Anthony M. Barsotti, Anette Ouwehand, Mina Fazollahi, Elias Coutavas, Kai Breuhahn, Olaf Neumann, Thomas Longerich, Tobias Pusterla, Maureen A. Powers, Keith M. Giles, Peter J. Leedman, Jochen Hess, David Grunwald, Harmen J. Bussemaker, Robert H. Singer, Peter Schirmacher, Carol Prives

David Grünwald

The p53 tumor suppressor utilizes multiple mechanisms to selectively regulate its myriad target genes, which in turn mediate diverse cellular processes. Here, using conventional and single-molecule mRNA analyses, we demonstrate that the nucleoporin Nup98 is required for full expression of p21, a key effector of the p53 pathway, but not several other p53 target genes. Nup98 regulates p21 mRNA levels by a posttranscriptional mechanism in which a complex containing Nup98 and the p21 mRNA 3'UTR protects p21 mRNA from degradation by the exosome. An in silico approach revealed another p53 target (14-3-3sigma) to be similarly regulated by Nup98. The expression …

Imp3 Expression Is Associated With Poor Outcome And Epigenetic Deregulation In Intrahepatic Cholangiocarcinoma, Yuanyuan Gao, Michelle Yang, Zhong Jiang, Bruce A. Woda, Arthur M. Mercurio, Jianjie Qin, Xinli Huang, Feng Zhang

Arthur M. Mercurio

IMP3 is a fetal protein not expressed in normal adult tissues. IMP3 is an oncoprotein and a useful biomarker for a variety of malignancies and is associated with reduced overall survival of a number of them. IMP3 expression and its prognostic value for patients with intrahepatic cholangiocarcinoma (ICC) have not been well investigated. The molecular mechanism underlying IMP3 expression in human cancer cells remains to be elucidated. Here we investigated IMP3 expression in ICC and adjacent nonneoplastic liver in 72 unifocal primary ICCs from a single institute by immunohistochemistry, immunoblotting, and real-time polymerase chain reaction. IMP3 was specifically expressed in …

Regulated Splicing Of The Alpha6 Integrin Cytoplasmic Domain Determines The Fate Of Breast Cancer Stem Cells, Hira Lal Goel, Tatiana Gritsko, Bryan Pursell, Cheng Chang, Leonard D. Shultz, Dale L. Greiner, Jens Henrik Norum, Rune Toftgard, Leslie M. Shaw, Arthur M. Mercurio

Arthur M. Mercurio

Although the alpha6beta1 integrin has been implicated in the function of breast and other cancer stem cells (CSCs), little is known about its regulation and relationship to mechanisms involved in the genesis of CSCs. We report that a CD44(high)/CD24(low) population, enriched for CSCs, is comprised of distinct epithelial and mesenchymal populations that differ in expression of the two alpha6 cytoplasmic domain splice variants: alpha6A and alpha6B. alpha6Bbeta1 expression defines the mesenchymal population and is necessary for CSC function, a function that cannot be executed by alpha6A integrins. The generation of alpha6Bbeta1 is tightly controlled and occurs as a consequence of …

Quantification Of Protoporphyrin Ix Accumulation In Glioblastoma Cells – A New Technique, Johnathan Lawrence, Ashish Patel, Richard Rovin, Robert Belton, Catherine Bammert, Robert Winn

Johnathan Lawrence

Introduction. 5-Aminolevulinic Acid (5-ALA) is a precursor of heme synthesis. A metabolite, protoporphyrin IX (PpIX), selectively accumulates in neoplastic tissue including glioblastoma. Presurgical administration of 5-ALA forms the basis of fluorescence-guided resection (FGR) of glioblastoma (GBM) tumors. However, not all gliomas accumulate sufficient quantities of PpIX to fluoresce, thus limiting the utility of FGR. We therefore developed an assay to determine cellular and pharmacological factors that impact PpIX fluorescence in GBM. This assay takes advantage of a GBM cell line engineered to express yellow fluorescent protein. Methods. The human GBM cell line U87MG was transfected with a YFP expression vector. …

A Functional Notch-Survivin Gene Signature In Basal Breast Cancer, Connie Wing-Ching Lee, Karl Simin, Qin Liu, Janet Plescia, Minakshi Guha, Ashraf Khan, Chung-Cheng Hsieh, Dario C. Altieri

Qin Liu

INTRODUCTION: Basal-type, or triple-negative, breast cancer (lacking estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 expression) is a high-risk disease for which no molecular therapies are currently available. We studied genetic signatures of basal breast cancer potentially suitable for therapeutic intervention. METHODS: We analyzed protein expression of the Notch-1 intracellular domain and survivin by immunohistochemistry in a series of basal breast cancer patients. A hierarchical clustering and overall survival analysis was carried out on a microarray mRNA database of 232 breast cancer patients. Fifteen published mRNA datasets containing estrogen receptor-negative or estrogen receptor-positive samples were subjected to meta-analysis …

Therapeutic Approaches To Aggressive Carcinomas Based On A Novel Vegf/Neuropilin Autocrine Pathway, Hira Lal Goel, Arthur M. Mercurio

Arthur M. Mercurio

Summary: Autocrine VEGF signaling in tumor cells contributes to de-differentiation and function of tumor initiating/stem cells. NRP2 is the nexus of a signaling pathway that promotes de-differentiation and sustains tumor initiating/stem sells. Anti-NRP2 therapy is worth pursuing, especially for high-grade cancers. Therapeutic Abs are available. This presentation was part of the retreat mini-symposium entitled: Biomarker Discovery and Targeted Therapeutics in Cancer.

Repression Of Mir-143 Mediates Cr (Vi)-Induced Tumor Angiogenesis Via Igf-Ir/Irs1/Erk/Il-8 Pathway., Jun He

Jun He

Hexavalent chromium [Cr (VI)] is a well-known human carcinogen associated with the increased risk of lung cancer. However, the mechanism underlying the Cr (VI)-induced carcinogenesis remains unclear due to the lack of suitable experimental models. In this study, we developed an in vitro model by transforming nontumorigenic human lung epithelial BEAS-2B cells through long-term exposure to Cr (VI). By utilizing this model, we found that miR-143 expression levels were dramatically repressed in Cr (VI)-transformed cells. The repression of miR-143 led to Cr (VI)-induced cell malignant transformation and angiogenesis via upregulation of insulin-like growth factor-1 receptor (IGF-IR) and insulin receptor substrate-1 …

Phenytoin Reduces 5-Ala Mediated Fluorescence In Glioblastoma Cells, Christopher Steele, Johnathan E. Lawrence, Richard A. Rovin, Robert J. Winn

Johnathan Lawrence

Glioblastoma multiforme (GBM) is a devastating form of cancer, and essentially all GBM tumors recur causing fatality. A new surgical technique, fluorescence-guided resection of GBM using 5-aminolevulinic acid (5-ala), improves the extent of resection and positively impacts the length and quality of patient survival. The fluorescence achieved in neoplastic tissue depends directly on the accumulation of porphyrins derived from the metabolism of the 5-ala prodrug within the cancer cell. However, 5-ala induced fluorescence has been reported to be inconsistent. In an effort to determine the cause of the inconsistent fluorescence, the authors investigated the effect of medications commonly prescribed to …

Glioblastoma Derived Exosomes Induce Apoptosis In Cytotoxic T Cells Through A Fas Ligand Mediated Mechanism, Keith Sabin, Richard Rovin, Johnathan Lawrence, Robert Belton, Robert Winn

Johnathan Lawrence

INTRODUCTION: Glioblastoma multiforme deploy s a number of weapons to thwart the immune system. Within the tumor microenvironment, cytotoxic T cells fall victim to Fas ligand (FasL) induced apoptosis. In prostate and colorectal cancer, exosomes can mediate this FasL induced T cell apoptosis. Exosomes are tiny, membrane bound vesicles that are released from a cell. They contain functional mRNA and protein and have cell surface molecules representative of their parent cell. It is not known if GBM derived exosomes can also mediate FasL triggered apoptosis. In this study, the role of tumor derived exosomes as the delivery vehicle for FasL …

Leptin Promotes Glioblastoma, Johnathan Lawrence, Nicholas Cook, Richard Rovin, Robert Winn

Johnathan Lawrence

The hormone leptin has a variety of functions. Originally known for its role in satiety and weight loss, leptin more recently has been shown to augment tumor growth in a variety of cancers. Within gliomas, there is a correlation between tumor grade and tumor expression of leptin and its receptor. This suggests that autocrine signaling within the tumor microenvironment may promote the growth of high-grade gliomas. Leptin does this through stimulation of cellular pathways that are also advantageous for tumor growth and recurrence: antiapoptosis, proliferation, angiogenesis, and migration. Conversely, a loss of leptin expression attenuates tumor growth. In animal models …

Effects Of Ss3-Adrenergic Receptor Agonist On Gene Expression Of Leptin In Glioblastoma, Johnathan E. Lawrence, Nicholas J. Cook, Richard A. Rovin, Robert J. Belton, Robert J. Winn

Johnathan Lawrence

In the 25 years since temozolomide entered phase I clinical trials, few new primary or adjuvant therapies have been developed for the treatment of glioblastoma multiforme (GBM) tumors. Our laboratory has been exploring novel methods for the treatment of GBMs. Recent studies indicate that the expression of the hormone leptin and its receptor (OBR) increases in gliomas and positively correlates with the malignancy of the tumor. Interestingly, ß3-adrenergic receptor agonists are known to decrease leptin expression in adipocytes but have not been examined in GBM cells. We hypothesized that b3-adrenergic agonists downregulate the expression of leptin and its receptor. In …

7 Alpha-Hydroxy-Beta-Sitosterol From Chisocheton Tomentosus Induces Apoptosis Via Dysregulation Of Cellular Bax/Bcl-2 Ratio And Cell Cycle Arrest By Downregulating Erk1/2 Activation, Noor Hasima Nagoor

Noor Hasima Nagoor

In continuation of our interest towards the elucidation of apoptotic pathways of cytotoxic phytocompounds, we have embarked upon a study on the anticancer effects of 7 alpha-hydroxy-beta-sitosterol (CT1), a rare natural phytosterol oxide isolated from Chisocheton tomentosus. CT1 was found to be cytotoxic on three different human tumor cell lines with minimal effects on normal cell controls, where cell viability levels were maintained >= 80% upon treatment. Our results showed that cell death in MCF-7 breast tumor cells was achieved through the induction of apoptosis via downregulation of the ERK1/2 signaling pathway. CT1 was also found to increase proapoptotic Bax …

Role Of Hypoxia And Glycolysis In The Development Of Multi-Drug Resistance In Human Tumor Cells And The Establishment Of An Orthotopic Multi-Drug Resistant Tumor Model In Nude Mice Using Hypoxic Pre-Conditioning, Lara Milane, Zhenfeng Duan, Mansoor M. Amiji

Mansoor M. Amiji

Background The development of multi-drug resistant (MDR) cancer is a significant challenge in the clinical treatment of recurrent disease. Hypoxia is an environmental selection pressure that contributes to the development of MDR. Many cancer cells, including MDR cells, resort to glycolysis for energy acquisition. This study aimed to explore the relationship between hypoxia, glycolysis, and MDR in a panel of human breast and ovarian cancer cells. A second aim of this study was to develop an orthotopic animal model of MDR breast cancer. Methods Nucleic and basal protein was extracted from a panel of human breast and ovarian cancer cells; …