Metabolic profiling of cancer cells has recently been established as a promising tool for the development of therapies and identification of cancer biomarkers. Here we characterized the metabolomic profile of human breast tumors and uncovered intrinsic metabolite signatures in these tumors using an untargeted discovery approach and validation of key metabolites. The oncometabolite 2-hydroxyglutarate (2HG) accumulated at high levels in a subset of tumors and human breast cancer cell lines. We discovered an association between increased 2HG levels and MYC pathway activation in breast cancer, and further corroborated this relationship using MYC overexpression and knockdown in human mammary epithelial and breast cancer cells. Further analyses revealed globally increased DNA methylation in 2HG-high tumors and identified a tumor subtype with high tissue 2HG and a distinct DNA methylation pattern that was associated with poor prognosis and occurred with higher frequency in African-American patients. Tumors of this subtype had a stem cell–like transcriptional signature and tended to overexpress glutaminase, suggestive of a functional relationship between glutamine and 2HG metabolism in breast cancer. Accordingly, 13C-labeled glutamine was incorporated into 2HG in cells with aberrant 2HG accumulation, whereas pharmacologic and siRNA-mediated glutaminase inhibition reduced 2HG levels. Our findings implicate 2HG as a candidate breast cancer oncometabolite associated with MYC activation and poor prognosis.
Atsushi Terunuma, Nagireddy Putluri, Prachi Mishra, Ewy A. Mathé, Tiffany H. Dorsey, Ming Yi, Tiffany A. Wallace, Haleem J. Issaq, Ming Zhou, J. Keith Killian, Holly S. Stevenson, Edward D. Karoly, King Chan, Susmita Samanta, DaRue Prieto, Tiffany Y.T. Hsu, Sarah J. Kurley, Vasanta Putluri, Rajni Sonavane, Daniel C. Edelman, Jacob Wulff, Adrienne M. Starks, Yinmeng Yang, Rick A. Kittles, Harry G. Yfantis, Dong H. Lee, Olga B. Ioffe, Rachel Schiff, Robert M. Stephens, Paul S. Meltzer, Timothy D. Veenstra, Thomas F. Westbrook, Arun Sreekumar, Stefan Ambs
Breast cancer (BC) can recur as metastatic disease many years after primary tumor removal, suggesting that disseminated tumor cells survive for extended periods in a dormant state that is refractory to conventional therapies. We have previously shown that altering the tumor microenvironment through fibrosis with collagen and fibronectin deposition can trigger tumor cells to switch from a dormant to a proliferative state. Here, we used an in vivo preclinical model and a 3D in vitro model of dormancy to evaluate the role of Src family kinase (SFK) in regulating this dormant-to-proliferative switch. We found that pharmacological inhibition of SFK signaling or
Lara H. El Touny, Anthony Vieira, Arnulfo Mendoza, Chand Khanna, Mark J. Hoenerhoff, Jeffrey E. Green
There is a considerable resurgence of interest in the role of aerobic glycolysis in cancer; however, increased glycolysis is frequently viewed as a consequence of oncogenic events that drive malignant cell growth and survival. Here we provide evidence that increased glycolytic activation itself can be an oncogenic event in a physiologically relevant 3D culture model. Overexpression of glucose transporter type 3 (GLUT3) in nonmalignant human breast cells activated known oncogenic signaling pathways, including EGFR, β1 integrin, MEK, and AKT, leading to loss of tissue polarity and increased growth. Conversely, reduction of glucose uptake in malignant cells promoted the formation of organized and growth-arrested structures with basal polarity, and suppressed oncogenic pathways. Unexpectedly and importantly, we found that unlike reported literature, in 3D the differences between “normal” and malignant phenotypes could not be explained by HIF-1α/2α, AMPK, or mTOR pathways. Loss of epithelial integrity involved activation of RAP1 via exchange protein directly activated by cAMP (EPAC), involving also O-linked N-acetylglucosamine modification downstream of the hexosamine biosynthetic pathway. The former, in turn, was mediated by pyruvate kinase M2 (PKM2) interaction with soluble adenylyl cyclase. Our findings show that increased glucose uptake activates known oncogenic pathways to induce malignant phenotype, and provide possible targets for diagnosis and therapeutics.
Yasuhito Onodera, Jin-Min Nam, Mina J. Bissell
Approximately 85% of lung cancers are non–small-cell lung cancers (NSCLCs), which are often diagnosed at an advanced stage and associated with poor prognosis. Currently, there are very few therapies available for NSCLCs due to the recalcitrant nature of this cancer. Mutations that activate the small GTPase KRAS are found in 20% to 30% of NSCLCs. Here, we report that inhibition of superoxide dismutase 1 (SOD1) by the small molecule ATN-224 induced cell death in various NSCLC cells, including those harboring
Andrea Glasauer, Laura A. Sena, Lauren P. Diebold, Andrew P. Mazar, Navdeep S. Chandel
Recent studies have underscored the importance of memory T cells in mediating protective immunity against pathogens and cancer. Pharmacological inhibition of regulators that mediate T cell differentiation promotes the differentiation of activated CD8+ T cells into memory cells. Nonetheless, pharmacological agents have broad targets and can induce undesirable immunosuppressive effects. Here, we tested the hypothesis that aptamer-targeted siRNA inhibition of mTOR complex 1 (mTORC1) function in CD8+ T cells can enhance their differentiation into memory T cells and potentiate antitumor immunity more effectively than the pharmacologic inhibitor rapamycin. To specifically target activated cells, we conjugated an siRNA targeting the mTORC1 component raptor to an aptamer that binds 4-1BB, a costimulatory molecule that is expressed on CD8+ T cells following TCR stimulation. We found that systemic administration of the 4-1BB aptamer-raptor siRNA to mice downregulated mTORC1 activity in the majority of CD8+ T cells, leading to the generation of a potent memory response that exhibited cytotoxic effector functions and enhanced vaccine-induced protective immunity in tumor-bearing mice. In contrast, while treatment with the general mTORC1 inhibitor rapamycin also enhanced antigen-activated CD8+ T cell persistence, the cytotoxic effector functions of the reactivated memory cells were reduced and the alloreactivity of DCs was diminished. Consistent with the immunological findings, mice treated with rapamycin, but not with 4-1BB aptamer-raptor siRNA, failed to reject a subsequent tumor challenge.
Alexey Berezhnoy, Iris Castro, Agata Levay, Thomas R. Malek, Eli Gilboa
Ionizing radiation (IR) and germline mutations in the retinoblastoma tumor suppressor gene (
Maya Kansara, Huei San Leong, Dan Mei Lin, Sophie Popkiss, Puiyi Pang, Dale W. Garsed, Carl R. Walkley, Carleen Cullinane, Jason Ellul, Nicole M. Haynes, Rod Hicks, Marieke L. Kuijjer, Anne-Marie Cleton-Jansen, Philip W. Hinds, Mark J. Smyth, David M. Thomas
Malignant melanoma is frequently driven by mutational activation of v-raf murine sarcoma viral oncogene homolog B1 (
Victoria Marsh Durban, Marian M. Deuker, Marcus W. Bosenberg, Wayne Phillips, Martin McMahon
Epigenetic dysregulation has emerged as a major contributor to tumorigenesis. Histone methylation is a well-established mechanism of epigenetic regulation that is dynamically modulated by histone methyltransferases and demethylases. The pathogenic role of histone methylation modifiers in non–small cell lung cancer (NSCLC), which is the leading cause of cancer deaths worldwide, remains largely unknown. Here, we found that the histone H3 lysine 36 (H3K36) demethylase KDM2A (also called FBXL11 and JHDM1A) is frequently overexpressed in NSCLC tumors and cell lines. KDM2A and its catalytic activity were required for in vitro proliferation and invasion of KDM2A-overexpressing NSCLC cells. KDM2A overexpression in NSCLC cells with low KDM2A levels increased cell proliferation and invasiveness. KDM2A knockdown abrogated tumor growth and invasive abilities of NSCLC cells in mouse xenograft models. We identified dual-specificity phosphatase 3 (
Klaus W. Wagner, Hunain Alam, Shilpa S. Dhar, Uma Giri, Na Li, Yongkun Wei, Dipak Giri, Tina Cascone, Jae-Hwan Kim, Yuanqing Ye, Asha S. Multani, Chia-Hsin Chan, Baruch Erez, Babita Saigal, Jimyung Chung, Hui-Kuan Lin, Xifeng Wu, Mien-Chie Hung, John V. Heymach, Min Gyu Lee
Tumor vessel dysfunction is a pivotal event in cancer progression. Using an in vivo neovascularization model, we identified G protein–coupled receptor kinase 2 (GRK2) as a key angiogenesis regulator. An impaired angiogenic response involving immature vessels was observed in mice hemizygous for
Verónica Rivas, Rita Carmona, Ramón Muñoz-Chápuli, Marta Mendiola, Laura Nogués, Clara Reglero, María Miguel-Martín, Ramón García-Escudero, Gerald W. Dorn II, David Hardisson, Federico Mayor Jr., Petronila Penela
Growth factors and their receptors coordinate neuronal differentiation during development, yet their roles in the pediatric tumor neuroblastoma remain unclear. Comparison of mRNA from benign neuroblastic tumors and neuroblastomas revealed that expression of the type III TGF-β receptor (
Erik H. Knelson, Angela L. Gaviglio, Alok K. Tewari, Michael B. Armstrong, Karthikeyan Mythreye, Gerard C. Blobe