Acute lymphoblastic leukemia (ALL) is the commonest childhood malignancy and is characterized by recurring structural genetic alterations. Previous studies of DNA methylation suggest epigenetic alterations may also be important, but an integrated genome-wide analysis of genetic and epigenetic alterations in ALL has not been performed. We analyzed 137 B-lineage and 30 T-lineage childhood ALL cases using microarray analysis of DNA copy number alterations and gene expression, and genome-wide cytosine methylation profiling using the
Maria E. Figueroa, Shann-Ching Chen, Anna K. Andersson, Letha A. Phillips, Yushan Li, Jason Sotzen, Mondira Kundu, James R. Downing, Ari Melnick, Charles G. Mullighan
Host response to cancer signals has emerged as a key factor in cancer development; however, the underlying molecular mechanism is not well understood. In this report, we demonstrate that activating transcription factor 3 (ATF3), a hub of the cellular adaptive response network, plays an important role in host cells to enhance breast cancer metastasis. Immunohistochemical analysis of patient tumor samples revealed that expression of ATF3 in stromal mononuclear cells, but not cancer epithelial cells, is correlated with worse clinical outcomes and is an independent predictor for breast cancer death. This finding was corroborated by data from mouse models showing less efficient breast cancer metastasis in
Chris C. Wolford, Stephen J. McConoughey, Swati P. Jalgaonkar, Marino Leon, Anand S. Merchant, Johnna L. Dominick, Xin Yin, Yiseok Chang, Erik J. Zmuda, Sandra A. O’Toole, Ewan K.A. Millar, Stephanie L. Roller, Charles L. Shapiro, Michael C. Ostrowski, Robert L. Sutherland, Tsonwin Hai
Metabolic reprogramming is an important driver of tumor progression; however, the metabolic regulators of tumor cell motility and metastasis are not understood. Here, we show that tumors maintain energy production under nutrient deprivation through the function of HSP90 chaperones compartmentalized in mitochondria. Using cancer cell lines, we found that mitochondrial HSP90 proteins, including tumor necrosis factor receptor–associated protein-1 (TRAP-1), dampen the activation of the nutrient-sensing AMPK and its substrate UNC-51–like kinase (ULK1), preserve cytoskeletal dynamics, and release the cell motility effector focal adhesion kinase (FAK) from inhibition by the autophagy initiator FIP200. In turn, this results in enhanced tumor cell invasion in low nutrients and metastatic dissemination to bone or liver in disease models in mice. Moreover, we found that phosphorylated ULK1 levels were correlated with shortened overall survival in patients with non–small cell lung cancer. These results demonstrate that mitochondrial HSP90 chaperones, including TRAP-1, overcome metabolic stress and promote tumor cell metastasis by limiting the activation of the nutrient sensor AMPK and preventing autophagy.
M. Cecilia Caino, Young Chan Chae, Valentina Vaira, Stefano Ferrero, Mario Nosotti, Nina M. Martin, Ashani Weeraratna, Michael O’Connell, Danielle Jernigan, Alessandro Fatatis, Lucia R. Languino, Silvano Bosari, Dario C. Altieri
Hormone therapies for advanced prostate cancer target the androgen receptor (AR) ligand-binding domain (LBD), but these ultimately fail and the disease progresses to lethal castration-resistant prostate cancer (CRPC). The mechanisms that drive CRPC are incompletely understood, but may involve constitutively active AR splice variants that lack the LBD. The AR N-terminal domain (NTD) is essential for AR activity, but targeting this domain with small-molecule inhibitors is complicated by its intrinsic disorder. Here we investigated EPI-001, a small-molecule antagonist of AR NTD that inhibits protein-protein interactions necessary for AR transcriptional activity. We found that EPI analogs covalently bound the NTD to block transcriptional activity of AR and its splice variants and reduced the growth of CRPC xenografts. These findings suggest that the development of small-molecule inhibitors that bind covalently to intrinsically disordered proteins is a promising strategy for development of specific and effective anticancer agents.
Jae-Kyung Myung, Carmen A. Banuelos, Javier Garcia Fernandez, Nasrin R. Mawji, Jun Wang, Amy H. Tien, Yu Chi Yang, Iran Tavakoli, Simon Haile, Kate Watt, Iain J. McEwan, Stephen Plymate, Raymond J. Andersen, Marianne D. Sadar
Some solid tumors have reduced posttranscriptional RNA editing by adenosine deaminase acting on RNA (ADAR) enzymes, but the functional significance of this alteration has been unclear. Here, we found the primary RNA-editing enzyme ADAR1 is frequently reduced in metastatic melanomas. In situ analysis of melanoma samples using progression tissue microarrays indicated a substantial downregulation of ADAR1 during the metastatic transition. Further, ADAR1 knockdown altered cell morphology, promoted in vitro proliferation, and markedly enhanced the tumorigenicity in vivo. A comparative whole genome expression microarray analysis revealed that ADAR1 controls the expression of more than 100 microRNAs (miRNAs) that regulate many genes associated with the observed phenotypes. Importantly, we discovered that ADAR1 fundamentally regulates miRNA processing in an RNA binding–dependent, yet RNA editing–independent manner by regulating Dicer expression at the translational level via let-7. In addition, ADAR1 formed a complex with DGCR8 that was mutually exclusive with the DGCR8-Drosha complex that processes pri-miRNAs in the nucleus. We found that cancer cells silence
Yael Nemlich, Eyal Greenberg, Rona Ortenberg, Michal J. Besser, Iris Barshack, Jasmine Jacob-Hirsch, Elad Jacoby, Eran Eyal, Ludmila Rivkin, Victor G. Prieto, Nitin Chakravarti, Lyn M. Duncan, David M. Kallenberg, Eitan Galun, Dorothy C. Bennett, Ninette Amariglio, Menashe Bar-Eli, Jacob Schachter, Gideon Rechavi, Gal Markel
Small intestine neuroendocrine tumors (SI-NETs) are the most common malignancy of the small bowel. Several clinical trials target PI3K/Akt/mTOR signaling; however, it is unknown whether these or other genes are genetically altered in these tumors. To address the underlying genetics, we analyzed 48 SI-NETs by massively parallel exome sequencing. We detected an average of 0.1 somatic single nucleotide variants (SNVs) per 106 nucleotides (range, 0–0.59), mostly transitions (C>T and A>G), which suggests that SI-NETs are stable cancers. 197 protein-altering somatic SNVs affected a preponderance of cancer genes, including
Michaela S. Banck, Rahul Kanwar, Amit A. Kulkarni, Ganesh K. Boora, Franziska Metge, Benjamin R. Kipp, Lizhi Zhang, Erik C. Thorland, Kay T. Minn, Ramesh Tentu, Bruce W. Eckloff, Eric D. Wieben, Yanhong Wu, Julie M. Cunningham, David M. Nagorney, Judith A. Gilbert, Matthew M. Ames, Andreas S. Beutler
TNF has remarkable antitumor activities; however, therapeutic applications have not been possible because of the systemic and lethal proinflammatory effects induced by TNF. Both the antitumor and inflammatory effects of TNF are mediated by the TNF receptor p55 (p55TNFR) (encoded by the
Filip Van Hauwermeiren, Marietta Armaka, Niki Karagianni, Ksanthi Kranidioti, Roosmarijn E. Vandenbroucke, Sonja Loges, Maarten Van Roy, Jan Staelens, Leen Puimège, Ajay Palagani, Wim Vanden Berghe, Panayiotis Victoratos, Peter Carmeliet, Claude Libert, George Kollias
JAK2 activity is tightly controlled through a self-inhibitory effect via its JAK homology domain 2 (JH2), which restricts the strength and duration of JAK2/STAT3 signaling under physiological conditions. Although multiple mutations within
Xiuting Chen, Zhe Ying, Xi Lin, Huanxin Lin, Jueheng Wu, Mengfeng Li, Libing Song
We examined the role of microRNAs (miRNAs) in targeting the stromal-derived factor 1α/CXCR4 (SDF-1α/CXCR4) axis to overcome chemoresistance of AML cells. Microarray analysis of OCI-AML3 cells revealed that the miRNA let-7a was downregulated by SDF-1α–mediated CXCR4 activation and increased by CXCR4 inhibition. Overexpression of let-7a in AML cell lines was associated with decreased c-Myc and BCL-XL protein expression and enhanced chemosensitivity, both in vitro and in vivo. We identified the transcription factor Yin Yang 1 (YY1) as a link between SDF-1α/CXCR4 signaling and let-7a, as YY1 was upregulated by SDF-1α and downregulated by treatment with a CXCR4 antagonist. ChIP assay confirmed the binding of YY1 to unprocessed let-7a DNA fragments, and treatment with
Ye Chen, Rodrigo Jacamo, Marina Konopleva, Ramiro Garzon, Carlo Croce, Michael Andreeff
High-risk types of human papilloma virus (HPV) are increasingly associated with oropharyngeal squamous cell carcinoma (OPSCC). Strikingly, patients with HPV-positive OPSCC are highly curable with ionizing radiation and have better survival compared with HPV-negative patients, but the underlying molecular mechanisms remain poorly understood. We applied an array-based approach to monitor global changes in CpG island hypermethylation between HPV-negative and HPV-positive OPSCCs and identified a specific pattern of differentially methylated regions that critically depends on the presence of viral transcripts. HPV-related alterations were confirmed for the majority of candidate gene promoters by mass spectrometric, quantitative methylation analysis. There was a significant inverse correlation between promoter hypermethylation of
Efterpi Kostareli, Dana Holzinger, Olga Bogatyrova, Thomas Hielscher, Gunnar Wichmann, Michaela Keck, Bernd Lahrmann, Niels Grabe, Christa Flechtenmacher, Christopher R. Schmidt, Tanguy Seiwert, Gerhard Dyckhoff, Andreas Dietz, Daniela Höfler, Michael Pawlita, Axel Benner, Franz X. Bosch, Peter Plinkert, Christoph Plass, Dieter Weichenhan, Jochen Hess