Medical Sciences Commons^™

Small Extracellular Vesicle-Mediated Itgb6 Sirna Delivery Downregulates The Αvβ6 Integrin And Inhibits Adhesion And Migration Of Recipient Prostate Cancer Cells, Shiv Ram Krishn, Vaughn Garcia, Nicole M Naranjo, Fabio Quaglia, Christopher D Shields, Maisha A Harris, Andrew V Kossenkov, Qin Liu, Eva Corey, Dario C Altieri, Lucia R Languino

Department of Cancer Biology Faculty Papers

The αVβ6 integrin, an epithelial-specific cell surface receptor absent in normal prostate and expressed during prostate cancer (PrCa) progression, is a therapeutic target in many cancers. Here, we report that transcript levels of ITGB6 (encoding the β6 integrin subunit) are significantly increased in metastatic castrate-resistant androgen receptor-negative prostate tumors compared to androgen receptor-positive prostate tumors. In addition, the αVβ6 integrin protein levels are significantly elevated in androgen receptor-negative PrCa patient derived xenografts (PDXs) compared to androgen receptor-positive PDXs. In vitro, the androgen receptor-negative PrCa cells express high levels of the αVβ6 integrin compared to androgen receptor-positive PrCa cells. Additionally, …

Stabilized Core Gene And Pathway Election Uncovers Pan-Cancer Shared Pathways And A Cancer-Specific Driver, Pathum Kossinna, Weijia Cai, Xuewen Lu, Carrie S Shemanko, Qingrun Zhang

Department of Cancer Biology Faculty Papers

Approaches systematically characterizing interactions via transcriptomic data usually follow two systems: (i) coexpression network analyses focusing on correlations between genes and (ii) linear regressions (usually regularized) to select multiple genes jointly. Both suffer from the problem of stability: A slight change of parameterization or dataset could lead to marked alterations of outcomes. Here, we propose Stabilized COre gene and Pathway Election (SCOPE), a tool integrating bootstrapped least absolute shrinkage and selection operator and coexpression analysis, leading to robust outcomes insensitive to variations in data. By applying SCOPE to six cancer expression datasets (BRCA, COAD, KIRC, LUAD, PRAD, and THCA) in …

The Nogo Receptor Ngr2, A Novel Αvβ3 Integrin Effector, Induces Neuroendocrine Differentiation In Prostate Cancer, Fabio Quaglia, Shiv Ram Krishn, Khalid Sossey-Alaoui, Priyanka Shailendra Rana, Elzbieta Pluskota, Pyung Hun Park, Christopher D. Shields, Stephen Lin, Peter Mccue, Andrew V. Kossenkov, Yanqing Wang, David W. Goodrich, Sheng-Yu Ku, Himisha Beltran, William K. Kelly, Eva Corey, Maja Klose, Christine Bandtlow, Qin Liu, Dario C. Altieri, Edward F. Plow, Lucia R. Languino

Department of Cancer Biology Faculty Papers

Androgen deprivation therapies aimed to target prostate cancer (PrCa) are only partially successful given the occurrence of neuroendocrine PrCa (NEPrCa), a highly aggressive and highly metastatic form of PrCa, for which there is no effective therapeutic approach. Our group has demonstrated that while absent in prostate adenocarcinoma, the αVβ3 integrin expression is increased during PrCa progression toward NEPrCa. Here, we show a novel pathway activated by αVβ3 that promotes NE differentiation (NED). This novel pathway requires the expression of a GPI-linked surface molecule, NgR2, also known as Nogo-66 receptor homolog 1. We show here that NgR2 is upregulated by αVβ3, …

Ctpathway: A Crosstalk-Based Pathway Enrichment Analysis Method For Cancer Research, Haizhou Liu, Mengqin Yuan, Ramkrishna Mitra, Xu Zhou, Min Long, Wanyue Lei, Shunheng Zhou, Yu-E Huang, Fei Hou, Christine M. Eischen, Wei Jiang

Department of Cancer Biology Faculty Papers

Background: Pathway enrichment analysis (PEA) is a common method for exploring functions of hundreds of genes and identifying disease-risk pathways. Moreover, different pathways exert their functions through crosstalk. However, existing PEA methods do not sufficiently integrate essential pathway features, including pathway crosstalk, molecular interactions, and network topologies, resulting in many risk pathways that remain uninvestigated.

Methods: To overcome these limitations, we develop a new crosstalk-based PEA method, CTpathway, based on a global pathway crosstalk map (GPCM) with >440,000 edges by combing pathways from eight resources, transcription factor-gene regulations, and large-scale protein-protein interactions. Integrating gene differential expression and crosstalk effects in …

Lysine Methyltransferase Nsd1 And Cancers: Any Role In Melanoma?, Imène Krossa, Thomas Strub, Andrew E Aplin, Robert Ballotti, Corine Bertolotto

Department of Cancer Biology Faculty Papers

Epigenetic regulations, that comprise histone modifications and DNA methylation, are essential to processes as diverse as development and cancer. Among the histone post-translational modifications, lysine methylation represents one of the most important dynamic marks. Here, we focused on methyltransferases of the nuclear binding SET domain 1 (NSD) family, that catalyze the mono- and di-methylation of histone H3 lysine 36. We review the loss of function mutations of NSD1 in humans that are the main cause of SOTOS syndrome, a disease associated with an increased risk of developing cancer. We then report the role of NSD1 in triggering tumor suppressive or …

A Genome-Wide Screen Identifies Pdpk1 As A Target To Enhance The Efficacy Of Mek1/2 Inhibitors, Weijia Cai, Nicole A. Wilski, Timothy J. Purwin, Megane Vernon, Manoela Tiago, Andrew E. Aplin

Department of Cancer Biology Faculty Papers

Melanomas frequently harbor activating NRAS mutations. However, limited advance has been made in developing targeted therapy options for NRAS mutant melanoma patients. MEK inhibitors (MEKi) show modest efficacy in the clinic and their actions need to be optimized. In this study, we performed a genome-wide CRISPR-Cas9-based screen and demonstrated that loss of Phosphoinositide-dependent kinase-1 (PDPK1) enhances the efficacy of MEKi. The synergistic effects of PDPK1 loss and MEKi was validated in NRAS mutant melanoma cell lines using pharmacological and molecular approaches. Combined PDPK1 inhibitors (PDPK1i) with MEKi suppressed NRAS mutant xenograft growth and induced gasdermin E-associated pyroptosis. In an immune-competent …

The Future Of Targeted Kinase Inhibitors In Melanoma, Signe Caksa, Usman Baqai, A E Aplin

Department of Cancer Biology Faculty Papers

Melanoma is a cancer of the pigment-producing cells of the body and its incidence is rising. Targeted inhibitors that act against kinases in the MAPK pathway are approved for BRAF-mutant metastatic cutaneous melanoma and increase patients' survival. Response to these therapies is limited by drug resistance and is less durable than with immune checkpoint inhibition. Conversely, rare melanoma subtypes have few therapeutic options for advanced disease and MAPK pathway targeting agents show minimal anti-tumor effects. Nevertheless, there is a future for targeted kinase inhibitors in melanoma: in new applications such as adjuvant or neoadjuvant therapy and in novel combinations with …

Targeting Sox10-Deficient Cells To Reduce The Dormant-Invasive Phenotype State In Melanoma, Claudia Capparelli, Timothy J. Purwin, Mckenna Glasheen, Signe Caksa, Manoela Tiago, Nicole A. Wilski, Danielle Pomante, Sheera Rosenbaum, Mai Q Nguyen, Weijia Cai, Janusz Franco-Barraza, R. Zheng, Md, Gaurav Kumar, I Chervoneva, Ayako Shimada, Vito W Rebecca, Adam E. Snook, Kim Hookim, Xiaowei Xu, Edna Cukierman, Meenhard Herlyn, A E Aplin

Department of Cancer Biology Faculty Papers

Cellular plasticity contributes to intra-tumoral heterogeneity and phenotype switching, which enable adaptation to metastatic microenvironments and resistance to therapies. Mechanisms underlying tumor cell plasticity remain poorly understood. SOX10, a neural crest lineage transcription factor, is heterogeneously expressed in melanomas. Loss of SOX10 reduces proliferation, leads to invasive properties, including the expression of mesenchymal genes and extracellular matrix, and promotes tolerance to BRAF and/or MEK inhibitors. We identify the class of cellular inhibitor of apoptosis protein-1/2 (cIAP1/2) inhibitors as inducing cell death selectively in SOX10-deficient cells. Targeted therapy selects for SOX10 knockout cells underscoring their drug tolerant properties. Combining cIAP1/2 inhibitor …

Ras-Mediated Tumor Stress Adaptation And The Targeting Opportunities It Presents, Alexandra Redding, A E Aplin, Elda Grabocka

Department of Cancer Biology Faculty Papers

Cellular stress is known to function in synergistic cooperation with oncogenic mutations during tumorigenesis to drive cancer progression. Oncogenic RAS is a strong inducer of a variety of pro-tumorigenic cellular stresses, and also enhances the ability of cells to tolerate these stresses through multiple mechanisms. Many of these oncogenic, RAS-driven, stress-adaptive mechanisms have also been implicated in tolerance and resistance to chemotherapy and to therapies that target the RAS pathway. Understanding how oncogenic RAS shapes cellular stress adaptation and how this functions in drug resistance is of vital importance for identifying new therapeutic targets and therapeutic combinations to treat RAS-driven …

Novel Oncogenic Transcription Factor Cooperation In Rb-Deficient Cancer, Amy C. Mandigo, Ayesha A Shafi, Jennifer J Mccann, Wei Yuan, Talya Laufer, Denisa Bogdan, Lewis Gallagher, Emanuela Dylgjeri, Galina Semenova, Irina A Vasilevskaya, M J Schiewer, Chris M Mcnair, Johann S De Bono, Karen E Knudsen

Department of Cancer Biology Faculty Papers

The retinoblastoma tumor suppressor (RB) is a critical regulator of E2F-dependent transcription, controlling a multitude of protumorigenic networks including but not limited to cell-cycle control. Here, genome-wide assessment of E2F1 function after RB loss in isogenic models of prostate cancer revealed unexpected repositioning and cooperation with oncogenic transcription factors, including the major driver of disease progression, the androgen receptor (AR). Further investigation revealed that observed AR/E2F1 cooperation elicited novel transcriptional networks that promote cancer phenotypes, especially as related to evasion of cell death. These observations were reflected in assessment of human disease, indicating the clinical relevance of the AR/E2F1 cooperome …

Sox10 Requirement For Melanoma Tumor Growth Is Due, In Part, To Immune-Mediated Effects, Sheera Rosenbaum, Manoela Tiago, Signe Caksa, Claudia Capparelli, Timothy J. Purwin, Gaurav Kumar, Mckenna Glasheen, Danielle Pomante, Daniel Kotas, I Chervoneva, A E Aplin

Department of Cancer Biology Faculty Papers

Developmental factors may regulate the expression of immune modulatory proteins in cancer, linking embryonic development and cancer cell immune evasion. This is particularly relevant in melanoma because immune checkpoint inhibitors are commonly used in the clinic. SRY-box transcription factor 10 (SOX10) mediates neural crest development and is required for melanoma cell growth. In this study, we investigate immune-related targets of SOX10 and observe positive regulation of herpesvirus entry mediator (HVEM) and carcinoembryonic-antigen cell-adhesion molecule 1 (CEACAM1). Sox10 knockout reduces tumor growth in vivo, and this effect is exacerbated in immune-competent models. Modulation of CEACAM1 expression but not HVEM elicits modest …

Targeting The Cdk6 Dependence Of Ph+ Acute Lymphoblastic Leukemia, Patrizia Porazzi, Marco De Dominici, Joseph Salvino, Bruno Calabretta

Department of Cancer Biology Faculty Papers

Ph+ ALL is a poor-prognosis leukemia subtype driven by the BCR-ABL1 oncogene, either the p190-or the p210-BCR/ABL isoform in a 70:30 ratio. Tyrosine Kinase inhibitors (TKIs) are the drugs of choice in the therapy of Ph+ ALL. In combination with standard chemotherapy, TKIs have markedly improved the outcome of Ph+ ALL, in particular if this treatment is followed by bone marrow transplantation. However, resistance to TKIs develops with high frequency, causing leukemia relapse that results in

A Cancer Ubiquitome Landscape Identifies Metabolic Reprogramming As Target Of Parkin Tumor Suppression, Ekta Agarwal, Aaron R Goldman, Hsin-Yao Tang, Andrew V Kossenkov, Jagadish C Ghosh, Lucia Languino, Valentina Vaira, David W Speicher, Dario C Altieri

Department of Cancer Biology Faculty Papers

Changes in metabolism that affect mitochondrial and glycolytic networks are hallmarks of cancer, but their impact in disease is still elusive. Using global proteomics and ubiquitome screens, we now show that Parkin, an E3 ubiquitin ligase and key effector of mitophagy altered in Parkinson's disease, shuts off mitochondrial dynamics and inhibits the non-oxidative phase of the pentose phosphate pathway. This blocks tumor cell movements, creates metabolic and oxidative stress, and inhibits primary and metastatic tumor growth. Uniformly down-regulated in cancer patients, Parkin tumor suppression requires its E3 ligase function, is reversed by antioxidants, and is independent of mitophagy. These data …

'Educated' Osteoblasts Reduce Osteoclastogenesis In A Bone-Tumor Mimetic Microenvironment., Alexus D. Kolb, Jinlu Dai, Evan T. Keller, Karen M. Bussard

Department of Cancer Biology Faculty Papers

Breast cancer (BC) metastases to bone disrupt the balance between osteoblasts and osteoclasts, leading to excessive bone resorption. We identified a novel subpopulation of osteoblasts with tumor-inhibitory properties, called educated osteoblasts (EOs). Here we sought to examine the effect of EOs on osteoclastogenesis during tumor progression. We hypothesized that EOs affect osteoclast development in the bone-tumor niche, leading to suppressed pre-osteoclast fusion and bone resorption. Conditioned media (CM) was analyzed for protein expression of osteoclast factors receptor activator of nuclear factor kappa-β ligand (RANKL), osteoprotegerin (OPG), and tumor necrosis factor alpha (TNFα) via ELISA. EOs were co-cultured with pre-osteoclasts on …

Myc Regulates Ribosome Biogenesis And Mitochondrial Gene Expression Programs Through Its Interaction With Host Cell Factor-1., Tessa M. Popay, Jing Wang, Clare M. Adams, Gregory Caleb Howard, Simona G. Codreanu, Stacy D. Sherrod, John A. Mclean, Lance R. Thomas, Shelly L. Lorey, Yuichi J. Machida, April M. Weissmiller, Christine M. Eischen, Qi Liu, William P. Tansey

Department of Cancer Biology Faculty Papers

The oncoprotein transcription factor MYC is a major driver of malignancy and a highly validated but challenging target for the development of anticancer therapies. Novel strategies to inhibit MYC may come from understanding the co-factors it uses to drive pro-tumorigenic gene expression programs, providing their role in MYC activity is understood. Here we interrogate how one MYC co-factor, host cell factor (HCF)-1, contributes to MYC activity in a human Burkitt lymphoma setting. We identify genes connected to mitochondrial function and ribosome biogenesis as direct MYC/HCF-1 targets and demonstrate how modulation of the MYC-HCF-1 interaction influences cell growth, metabolite profiles, global …

Hitting The Bullseye: Are Extracellular Vesicles On Target?, Nicole Noren Hooten, María Yáñez-Mó, Rachel M. Derita, Ashley Russell, Peter Quesenberry, Bharat Ramratnam, Paul D Robbins, Dolores Di Vizio, Sicheng Wen, Kenneth W Witwer, Lucia R Languino

Department of Cancer Biology Faculty Papers

No abstract provided.

The Membrane-Associated Form Of Cyclin D1 Enhances Cellular Invasion, Ke Chen, Xuanmao Jiao, Anthony Ashton, Agnese Di Rocco, Timothy G Pestell, Yunguang Sun, Jun Zhao, Mathew C Casimiro, Zhiping Li, Michael P Lisanti, Peter Mccue, Duanwen Shen, Samuel Achilefu, Hallgeir Rui, Richard G Pestell

Department of Cancer Biology Faculty Papers

The essential G1-cyclin, CCND1, is a collaborative nuclear oncogene that is frequently overexpressed in cancer. D-type cyclins bind and activate CDK4 and CDK6 thereby contributing to G1-S cell-cycle progression. In addition to the nucleus, herein cyclin D1 was also located in the cytoplasmic membrane. In contrast with the nuclear-localized form of cyclin D1 (cyclin D1NL), the cytoplasmic membrane-localized form of cyclin D1 (cyclin D1MEM) induced transwell migration and the velocity of cellular migration. The cyclin D1MEM was sufficient to induce G1-S cell-cycle progression, cellular proliferation, and colony formation. The cyclin D1MEM was sufficient to induce phosphorylation of the serine threonine …

Endogenous Cyclin D1 Promotes The Rate Of Onset And Magnitude Of Mitogenic Signaling Via Akt1 Ser473 Phosphorylation., Ke Chen, Xuanmao Jiao, Agnese Di Rocco, Duanwen Shen, Shaohua Xu, Adam Ertel, Zuoren Yu, Gabriele Di Sante, Min Wang, Zhiping Li, Timothy G Pestell, Mathew C Casimiro, Emmanuel Skordalakes, Samuel Achilefu, Richard G Pestell

Department of Cancer Biology Faculty Papers

Cyclin D1 encodes the regulatory subunit of a holoenzyme that phosphorylates RB and functions as a collaborative nuclear oncogene. The serine threonine kinase Akt plays a pivotal role in the control of cellular metabolism, survival, and mitogenic signaling. Herein, Akt1-mediated phosphorylation of downstream substrates in the mammary gland is reduced by cyclin D1 genetic deletion and is induced by mammary-gland-targeted cyclin D1 overexpression. Cyclin D1 is associated with Akt1 and augments the rate of onset and maximal cellular Akt1 activity induced by mitogens. Cyclin D1 is identified in a cytoplasmic-membrane-associated pool, and cytoplasmic-membrane-localized cyclin D1-but not nuclear-localized cyclin D1-recapitulates Akt1 …

Interaction Of The Oncoprotein Transcription Factor Myc With Its Chromatin Cofactor Wdr5 Is Essential For Tumor Maintenance., Lance R. Thomas, Clare M. Adams, Jing Wang, April M. Weissmiller, Joy Creighton, Shelly L. Lorey, Qi Liu, Stephen W. Fesik, Christine M. Eischen, William P. Tansey

Department of Cancer Biology Faculty Papers

The oncoprotein transcription factor MYC is overexpressed in the majority of cancers. Key to its oncogenic activity is the ability of MYC to regulate gene expression patterns that drive and maintain the malignant state. MYC is also considered a validated anticancer target, but efforts to pharmacologically inhibit MYC have failed. The dependence of MYC on cofactors creates opportunities for therapeutic intervention, but for any cofactor this requires structural understanding of how the cofactor interacts with MYC, knowledge of the role it plays in MYC function, and demonstration that disrupting the cofactor interaction will cause existing cancers to regress. One cofactor …

Sighting Acute Myocardial Infarction Through Platelet Gene Expression., Giuliana Gobbi, Cecilia Carubbi, Guidantonio Malagoli Tagliazucchi, Elena Masselli, Prisco Mirandola, Filippo Pigazzani, Antonio Crocamo, Maria Francesca Notarangelo, Sergio Suma, Elvezia Paraboschi, Giuseppe Maglietta, Srikanth Nagalla, Giulia Pozzi, Daniela Galli, Mauro Vaccarezza, Paolo Fortina, Sankar Addya, Adam Ertel, Paul Bray, Stefano Duga, Carlo Berzuini, Marco Vitale, Diego Ardissino

Department of Cancer Biology Faculty Papers

Acute myocardial infarction is primarily due to coronary atherosclerotic plaque rupture and subsequent thrombus formation. Platelets play a key role in the genesis and progression of both atherosclerosis and thrombosis. Since platelets are anuclear cells that inherit their mRNA from megakaryocyte precursors and maintain it unchanged during their life span, gene expression profiling at the time of an acute myocardial infarction provides information concerning the platelet gene expression preceding the coronary event. In ST-segment elevation myocardial infarction (STEMI), a gene-by-gene analysis of the platelet gene expression identified five differentially expressed genes: FKBP5, S100P, SAMSN1, CLEC4E and S100A12. The logistic regression …

Slc36a1-Mtorc1 Signaling Drives Acquired Resistance To Cdk4/6 Inhibitors., Akihiro Yoshida, Yiwen Bu, Shuo Qie, John Wrangle, E. Ramsay Camp, E. Starr Hazard, Gary Hardiman, Renée De Leeuw, Karen E. Knudsen, J. Alan Diehl

Department of Cancer Biology Faculty Papers

The cyclin-dependent kinase 4/6 (CDK4/6) kinase is dysregulated in melanoma, highlighting it as a potential therapeutic target. CDK4/6 inhibitors are being evaluated in trials for melanoma and additional cancers. While beneficial, resistance to therapy is a concern, and the molecular mechanisms of such resistance remain undefined. We demonstrate that reactivation of mammalian target of rapamycin 1 (mTORC1) signaling through increased expression of the amino acid transporter, solute carrier family 36 member 1 (SLC36A1), drives resistance to CDK4/6 inhibitors. Increased expression of SLC36A1 reflects two distinct mechanisms: (i) Rb loss, which drives SLC36A1 via reduced suppression of E2f; (ii) fragile X …

Identification Of Monocyte-Like Precursors Of Granulocytes In Cancer As A Mechanism For Accumulation Of Pmn-Mdscs., Jérôme Mastio, Thomas Condamine, George Dominguez, Andrew V Kossenkov, Laxminarasimha Donthireddy, Filippo Veglia, Cindy Lin, Fang Wang, Shuyu Fu, Jie Zhou, Patrick Viatour, Sergio Lavilla-Alonso, Alexander T. Polo, Evgenii N. Tcyganov, Charles Mulligan, Brian Nam, Joseph Bennett, Gregory Masters, Michael Guarino, Amit Kumar, Yulia Nefedova, Robert H. Vonderheide, Lucia R. Languino, Scott I. Abrams, Dmitry I. Gabrilovich

Department of Cancer Biology Faculty Papers

We have identified a precursor that differentiates into granulocytes in vitro and in vivo yet belongs to the monocytic lineage. We have termed these cells monocyte-like precursors of granulocytes (MLPGs). Under steady state conditions, MLPGs were absent in the spleen and barely detectable in the bone marrow (BM). In contrast, these cells significantly expanded in tumor-bearing mice and differentiated to polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs). Selective depletion of monocytic cells had no effect on the number of granulocytes in naive mice but decreased the population of PMN-MDSCs in tumor-bearing mice by 50%. The expansion of MLPGs was found to be …

The Bone Extracellular Matrix As An Ideal Milieu For Cancer Cell Metastases., Alexus D. Kolb, Karen M. Bussard

Department of Cancer Biology Faculty Papers

Bone is a preferential site for cancer metastases, including multiple myeloma, prostate, and breast cancers.The composition of bone, especially the extracellular matrix (ECM), make it an attractive site for cancer cell colonization and survival. The bone ECM is composed of living cells embedded within a matrix composed of both organic and inorganic components. Among the organic components, type I collagen provides the tensile strength of bone. Inorganic components, including hydroxyapatite crystals, are an integral component of bone and provide bone with its rigidity. Under normal circumstances, two of the main cell types in bone, the osteoblasts and osteoclasts, help to …

Myc-Mediated Transcriptional Regulation Of The Mitochondrial Chaperone Trap1 Controls Primary And Metastatic Tumor Growth., Ekta Agarwal, Brian J. Altman, Jae Ho Seo, Jagadish C. Ghosh, Andrew V Kossenkov, Hsin-Yao Tang, Shiv Ram Krishn, Lucia R. Languino, Dmitry I. Gabrilovich, David W. Speicher, Chi V. Dang, Dario C. Altieri

Department of Cancer Biology Faculty Papers

The role of mitochondria in cancer continues to be debated, and whether exploitation of mitochondrial functions is a general hallmark of malignancy or a tumor- or context-specific response is still unknown. Using a variety of cancer cell lines and several technical approaches, including siRNA-mediated gene silencing, ChIP assays, global metabolomics and focused metabolite analyses, bioenergetics, and cell viability assays, we show that two oncogenic Myc proteins, c-Myc and N-Myc, transcriptionally control the expression of the mitochondrial chaperone TNFR-associated protein- 1 (TRAP1) in cancer. In turn, this Myc-mediated regulation preserved the folding and function of mitochondrial oxidative phosphorylation (OXPHOS) complex II …

M6a Mrna Demethylase Fto Regulates Melanoma Tumorigenicity And Response To Anti-Pd-1 Blockade, Seungwon Yang, Jiangbo Wei, Yan-Hong Cui, Gayoung Park, Palak Shah, Yu Deng, Andrew E. Aplin, Zhike Lu, Seungmin Hwang, Chuan He, Yu-Ying He

Department of Cancer Biology Faculty Papers

Melanoma is one of the most deadly and therapy-resistant cancers. Here we show that N⁶-methyladenosine (m⁶A) mRNA demethylation by fat mass and obesity-associated protein (FTO) increases melanoma growth and decreases response to anti-PD-1 blockade immunotherapy. FTO level is increased in human melanoma and enhances melanoma tumorigenesis in mice. FTO is induced by metabolic starvation stress through the autophagy and NF-κB pathway. Knockdown of FTO increases m⁶A methylation in the critical protumorigenic melanoma cell-intrinsic genes including PD-1 (PDCD1), CXCR4, and SOX10, leading to increased RNA decay through the m⁶A reader YTHDF2. Knockdown of …

Tumor-Derived Extracellular Vesicles Require Β1 Integrins To Promote Anchorage-Independent Growth., Rachel M. Derita, Aejaz Sayeed, Vaughn Garcia, Shiv Ram Krishn, Christopher D. Shields, Srawasti Sarker, Andrea Friedman, Peter Mccue, Sudheer Kumar Molugu, Ulrich Rodeck, Adam P. Dicker, Lucia R. Languino

Department of Cancer Biology Faculty Papers

The β1 integrins, known to promote cancer progression, are abundant in extracellular vesicles (EVs). We investigated whether prostate cancer (PrCa) EVs affect anchorage-independent growth and whether β1 integrins are required for this effect. Specifically using a cell-line-based genetic rescue and an in vivo PrCa model, we show that gradient-purified small EVs (sEVs) from either cancer cells or blood from tumor-bearing TRAMP (transgenic adenocarcinoma of the mouse prostate) mice promote anchorage-independent growth of PrCa cells. In contrast, sEVs from cultured PrCa cells harboring a short hairpin RNA to β1, from wild-type mice or from TRAMP mice carrying a β1 conditional ablation …

Osteoblasts Are "Educated" By Crosstalk With Metastatic Breast Cancer Cells In The Bone Tumor Microenvironment., Alexus D. Kolb, Alison B. Shupp, Dimpi Mukhopadhyay, Frank C. Marini, Karen M. Bussard

Department of Cancer Biology Faculty Papers

INTRODUCTION: In a cancer-free environment in the adult, the skeleton continuously undergoes remodeling. Bone-resorbing osteoclasts excavate erosion cavities, and bone-depositing osteoblasts synthesize osteoid matrix that forms new bone, with no net bone gain or loss. When metastatic breast cancer cells invade the bone, this balance is disrupted. Patients with bone metastatic breast cancer frequently suffer from osteolytic bone lesions that elicit severe bone pain and fractures. Bisphosphonate treatments are not curative. Under ideal circumstances, osteoblasts would synthesize new matrix to fill in erosion cavities caused by osteoclasts, but this is not what occurs. Our prior evidence demonstrated that osteoblasts are …

Cyclin D1 Integrates G9a-Mediated Histone Methylation., Zhiping Li, Xuanmao Jiao, Gabriele Di Sante, Adam Ertel, Mathew C. Casimiro, Min Wang, Sanjay Katiyar, Xiaoming Ju, D. V. Klopfenstein, Aydin Tozeren, William Dampier, Iouri Chepelev, Albert Jeltsch, Richard G. Pestell

Department of Cancer Biology Faculty Papers

Lysine methylation of histones and non-histone substrates by the SET domain containing protein lysine methyltransferase (KMT) G9a/EHMT2 governs transcription contributing to apoptosis, aberrant cell growth, and pluripotency. The positioning of chromosomes within the nuclear three-dimensional space involves interactions between nuclear lamina (NL) and the lamina-associated domains (LAD). Contact of individual LADs with the NL are dependent upon H3K9me2 introduced by G9a. The mechanisms governing the recruitment of G9a to distinct subcellular sites, into chromatin or to LAD, is not known. The cyclin D1 gene product encodes the regulatory subunit of the holoenzyme that phosphorylates pRB and NRF1 thereby governing cell-cycle …

Parp-1 Regulates Dna Repair Factor Availability., M J Schiewer, Amy C. Mandigo, Nicolas Gordon, Fangjin Huang, Sanchaika Gaur, Renée De Leeuw, Shuang G Zhao, Joseph Evans, Sumin Han, Theodore Parsons, Ruth Birbe, Peter Mccue, Christopher Mcnair, Saswati N. Chand, Ylenia Cendon-Florez, Peter Gallagher, Jennifer J Mccann, Neermala Poudel Neupane, Ayesha A Shafi, Emanuela Dylgjeri, Lucas J Brand, Tapio Visakorpi, Ganesh V Raj, Costas D. Lallas, Edouard J Trabulsi, Leonard G Gomella, Adam Dicker Md, Phd, William Kevin Kelly, Benjamin E Leiby, Beatrice Knudsen, Felix Y Feng, Karen E Knudsen

Department of Cancer Biology Faculty Papers

PARP-1 holds major functions on chromatin, DNA damage repair and transcriptional regulation, both of which are relevant in the context of cancer. Here, unbiased transcriptional profiling revealed the downstream transcriptional profile of PARP-1 enzymatic activity. Further investigation of the PARP-1-regulated transcriptome and secondary strategies for assessing PARP-1 activity in patient tissues revealed that PARP-1 activity was unexpectedly enriched as a function of disease progression and was associated with poor outcome independent of DNA double-strand breaks, suggesting that enhanced PARP-1 activity may promote aggressive phenotypes. Mechanistic investigation revealed that active PARP-1 served to enhance E2F1 transcription factor activity, and specifically promoted …

Mir-196b Target Screen Reveals Mechanisms Maintaining Leukemia Stemness With Therapeutic Potential., Sara E. Meyer, David E. Muench, Andrew M. Rogers, Tess J. Newkold, Emily Orr, Eric O'Brien, John P. Perentesis, John G. Doench, Ashish Lal, Patrick J. Morris, Craig J. Thomas, Judy Lieberman, Edwina Mcglinn, Bruce J. Aronow, Nathan Salomonis, H. Leighton Grimes

Department of Cancer Biology Faculty Papers

We have shown that antagomiR inhibition of miRNA miR-21 and miR-196b activity is sufficient to ablate MLL-AF9 leukemia stem cells (LSC) in vivo. Here, we used an shRNA screening approach to mimic miRNA activity on experimentally verified miR-196b targets to identify functionally important and therapeutically relevant pathways downstream of oncogenic miRNA in MLL-r AML. We found Cdkn1b (p27^Kip1) is a direct miR-196b target whose repression enhanced an embryonic stem cell–like signature associated with decreased leukemia latency and increased numbers of leukemia stem cells in vivo. Conversely, elevation of p27^Kip1 significantly reduced MLL-r leukemia self-renewal, promoted monocytic differentiation …