Oncology
Abstract
We used the cancer intrinsic property of oncogene-induced DNA damage as the base for a conditional synthetic lethality approach. To target mechanisms important for cancer cell adaptation to genotoxic stress and thereby to achieve cancer cell-specific killing, we combined inhibition of the kinases ATR and Wee1. Wee1 regulates cell cycle progression, whereas ATR is an apical kinase in the DNA damage response. In an orthotopic breast cancer model, tumor-selective synthetic lethality between bioavailable ATR and Wee1 inhibitors led to tumor remission and inhibited metastasis with minimal side effects. ATR and Wee1 inhibition had a higher synergistic effect in cancer stem cells than in bulk cancer cells, compensating for the lower sensitivity of cancer stem cells to the individual drugs. Mechanistically, the combination treatment caused cells with unrepaired or under-replicated DNA to enter mitosis leading to mitotic catastrophe. As these inhibitors of ATR and Wee1 are already in phase I/II clinical trials, this knowledge could soon be translated into the clinic, especially as we showed that the combination treatment targets a wide range of tumor cells. Particularly the anti-metastatic effect of combined Wee1/ATR inhibition and the low toxicity of ATR inhibitors compared to Chk1 inhibitors has great clinical potential.
Authors
Amirali B. Bukhari, Cody W. Lewis, Joanna J. Pearce, Deandra Luong, Gordon K. Chan, Armin M. Gamper
PARP inhibition enhances tumor cell-intrinsic immunity in ERCC1-deficient non-small cell lung cancer
Abstract
The cyclic GMP-AMP synthase–stimulator of interferon genes (cGAS/STING) pathway detects cytosolic DNA to activate innate immune responses. Poly(ADP-ribose) polymerase inhibitors (PARPi) selectively target cancer cells with DNA repair deficiencies such as those caused by BRCA1 mutations or ERCC1 defects. Using isogenic cell lines and patient-derived samples, we showed that ERCC1-defective non-small cell lung cancer (NSCLC) cells exhibit an enhanced type I interferon transcriptomic signature, and that low ERCC1 expression correlates with increased lymphocytic infiltration. We demonstrated that clinical PARPi, including olaparib and rucaparib, have cell-autonomous immunomodulatory properties in ERCC1-defective NSCLC and BRCA1-defective triple-negative breast cancer (TNBC) cells. Mechanistically, PARPi generated cytoplasmic chromatin fragments with micronuclei characteristics; these were found to activate cGAS/STING, downstream type I interferon signaling and CCL5 secretion. Importantly, these effects were suppressed in PARP1-null TNBC cells, suggesting that this phenotype resulted from an on-target effect of PARPi on PARP1. PARPi also potentiated interferon-γ-induced PD-L1 expression in NSCLC cell lines and in fresh patient tumor cells; this effect was enhanced in ERCC1-deficient contexts. Our data provide the preclinical rationale for using PARPi as immunomodulatory agents in appropriately molecularly-selected populations.
Authors
Roman M. Chabanon, Gareth Muirhead, Dragomir B. Krastev, Julien Adam, Daphné Morel, Marlène Garrido, Andrew Lamb, Clémence Hénon, Nicolas Dorvault, Mathieu Rouanne, Rebecca Marlow, Ilirjana Bajrami, Marta Llorca Cardeñosa, Asha Konde, Benjamin Besse, Alan Ashworth, Stephen J. Pettitt, Syed Haider, Aurélien Marabelle, Andrew N.J. Tutt, Jean-Charles Soria, Christopher J. Lord, Sophie Postel-Vinay
Abstract
Adoptive transfer of T cell receptor–engineered (TCR-engineered) T cells is a promising approach in cancer therapy but needs improvement for more effective treatment of solid tumors. While most clinical approaches have focused on CD8+ T cells, the importance of CD4+ T cells in mediating tumor regression has become apparent. Regarding shared (self) tumor antigens, it is unclear whether the human CD4+ T cell repertoire has been shaped by tolerance mechanisms and lacks highly functional TCRs suitable for therapy. Here, TCRs against the tumor-associated antigen NY-ESO-1 were isolated either from human CD4+ T cells or from mice that express a diverse human TCR repertoire with HLA-DRA/DRB1*0401 restriction and are NY-ESO-1 negative. NY-ESO-1–reactive TCRs from the mice showed superior recognition of tumor cells and higher functional activity compared with TCRs from humans. We identified a candidate TCR, TCR-3598_2, which was expressed in CD4+ T cells and caused tumor regression in combination with NY-ESO-1–redirected CD8+ T cells in a mouse model of adoptive T cell therapy. These data suggest that MHC II–restricted TCRs against NY-ESO-1 from a nontolerant nonhuman host are of optimal affinity and that the combined use of MHC I– and II–restricted TCRs against NY-ESO-1 can make adoptive T cell therapy more effective.
Authors
Lucia Poncette, Xiaojing Chen, Felix K.M. Lorenz, Thomas Blankenstein
Abstract
While immune checkpoint blockade leads to potent antitumor efficacy, it also leads to immune-related adverse events in cancer patients. These toxicities stem from systemic immune activation resulting in inflammation of multiple organs, including the gastrointestinal tract, lung, and endocrine organs. We developed a dual variable domain immunoglobulin of anti-CTLA4 antibody (anti-CTLA4 DVD, where CTLA4 is defined as cytotoxic T lymphocyte–associated antigen-4) possessing an outer tumor-specific antigen-binding site engineered to shield the inner anti-CTLA4–binding domain. Upon reaching the tumor, the outer domain was cleaved by membrane type-serine protease 1 (MT-SP1) present in the tumor microenvironment, leading to enhanced localization of CTLA4 blockade. Anti-CTLA4 DVD markedly reduced multiorgan immune toxicity by preserving tissue-resident Tregs in Rag 1–/– mice that received naive donor CD4+ T cells from WT C57BL/6j mice. Moreover, anti-CTLA4 DVD induced potent antitumor effects by decreasing tumor-infiltrating Tregs and increasing the infiltration of antigen-specific CD8+ T lymphocytes in TRAMP-C2–bearing C57BL/6j mice. Treg depletion was mediated through the antibody-dependent cellular cytotoxicity (ADCC) mechanism, as anti-CTLA4 without the FcγR-binding portion (anti-CTLA4 DANA) spared Tregs, preventing treatment-induced toxicities. In summary, our results demonstrate an approach to anti-CTLA4 blockade that depletes tumor-infiltrating, but not tissue-resident, Tregs, preserving antitumor effects while minimizing toxicity. Thus, our tumor-conditional anti-CTLA4 DVD provides an avenue for uncoupling antitumor efficacy from immunotherapy-induced toxicities.
Authors
Chien-Chun Steven Pai, Donald M. Simons, Xiaoqing Lu, Michael Evans, Junnian Wei, Yung-hua Wang, Mingyi Chen, John Huang, Chanhyuk Park, Anthony Chang, Jiaxi Wang, Susan Westmoreland, Christine Beam, Dave Banach, Diana Bowley, Feng Dong, Jane Seagal, Wendy Ritacco, Paul L. Richardson, Soumya Mitra, Grace Lynch, Pete Bousquet, John Mankovich, Gillian Kingsbury, Lawrence Fong
Abstract
The adenomatous polyposis coli (APC) gene plays a pivotal role in the pathogenesis of colorectal carcinoma (CRC), but remains a challenge for drug development. Long non-coding RNAs (lncRNAs) are invaluable in identifying cancer pathologies, and providing therapeutic options for cancer patients. Here, we identified a lncRNA (lncRNA-APC1) activated by APC through lncRNA microarray screening, and examined its expression among a large cohort of CRC tissues. A decrease in lncRNA-APC1 expression was positively associated with lymph node and/or distant metastasis, a more advanced clinical stage, as well as a poor prognosis of CRC patients. Additionally, APC can enhance lncRNA-APC1 expression by suppressing the enrichment of PPARα on the lncRNA-APC1 promoter. Furthermore, enforced lncRNA-APC1 expression was sufficient to inhibit CRC cell growth, metastasis and tumor angiogenesis by suppressing exosome production through directly binding Rab5b mRNA and reducing its stability. Importantly, exosomes derived from lncRNA-APC1-silenced CRC cells promoted angiogenesis by activating the MAPK pathway in endothelial cells, and moreover, exosomal Wnt1 largely enhanced CRC cell proliferation and migration through non-canonicial Wnt signaling. Collectively, lncRNA-APC1 is a critical lncRNA regulated by APC in the pathogenesis of CRC. Our findings suggest an APC-regulated lncRNA-APC1 program as an exploitable therapeutic maneuver for CRC patients.
Authors
Feng-Wei Wang, Chen-Hui Cao, Kai Han, Yong-Xiang Zhao, Mu-Yan Cai, Zhi-Cheng Xiang, Jia-Xing Zhang, Jie-Wei Chen, Li-Ping Zhong, Yong Huang, Su-Fang Zhou, Xiao-Han Jin, Xin-Yuan Guan, Rui-Hua Xu, Dan Xie
Abstract
Prostate cancer (PCa) progressed to castration resistance (CRPC) is a fatal disease. CRPC tumors develop resistance to new-generation anti-androgen enzalutamide through lineage plasticity, characterized by epithelial-mesenchymal transition (EMT) and basal-like phenotype. FOXA1 is a transcription factor essential for epithelial lineage differentiation. Here, we demonstrate that FOXA1 loss leads to remarkable up-regulation of transforming growth factor beta 3 (TGFB3), which encodes a ligand of TGF-β pathway. Mechanistically, this is due to genomic occupancy of FOXA1 on an upstream enhancer of TGFB3 gene to directly inhibit its transcription. Functionally, FOXA1 down-regulation induces TGF-β signaling, EMT, and cell motility, which is effectively blocked by TGF-β receptor I inhibitor Galunisertib (LY2157299). Tissue microarray analysis confirmed reduced levels of FOXA1 protein and a concordant increase in TGF-β signaling, indicated by SMAD2 phosphorylation, in CRPC as compared to primary tumors. Importantly, combinatorial LY2157299 treatment sensitized PCa cells to enzalutamide, leading to synergistic effects in inhibiting cell invasion in vitro and xenograft CRPC tumor growth and metastasis in vivo. Therefore, our study establishes FOXA1 as an important regulator of lineage plasticity mediated in part by TGF-β signaling and supports a novel therapeutic strategy to control lineage switching and potentially extend clinical response to antiandrogen therapies.
Authors
Bing Song, Su-Hong Park, Jonathan C. Zhao, Ka-wing Fong, Shangze Li, Yongik Lee, Yeqing A. Yang, Subhasree Sridhar, Xiaodong Lu, Sarki A. Abdulkadir, Robert L. Vessella, Colm Morrissey, Timothy M. Kuzel, William J. Catalona, Ximing J. Yang, Jindan Yu
Abstract
Loss of phosphatase and tensin homolog (PTEN) represents one hallmark of prostate cancer (PCa). However, restoration of PTEN or inhibition of the activated PI3K-AKT pathway has shown limited success, prompting us to identify obligate targets for disease intervention. We hypothesized that PTEN loss might expose cells to unique epigenetic vulnerabilities. Here, we identified a synthetic lethal relationship between PTEN and BRG1, an ATPase subunit of the SWI/SNF chromatin remodeling complex. Higher BRG1 expression in tumors with low PTEN expression was associated with a worse clinical outcome. Genetically engineered mice (GEMs) and organoid assays confirmed that ablation of PTEN sensitized the cells to BRG1 depletion. Mechanistically, PTEN loss stabilized BRG1 protein through the inhibition of the AKT-GSK3β-FBXW7 axis. Increased BRG1 expression in PTEN-deficient PCa cells led to chromatin remodeling into configurations that drive a protumorigenic transcriptome, causing cells to become further addicted to BRG1. Furthermore, we showed in preclinical models that BRG1 antagonist selectively inhibited the progression of PTEN-deficient prostate tumors. Together, our results highlight the synthetic lethal relationship between PTEN and BRG1, and support targeting BRG1 as an effective approach to the treatment of PTEN-deficient PCa.
Authors
Yufeng Ding, Ni Li, Baijun Dong, Wangxin Guo, Hui Wei, Qilong Chen, Huairui Yuan, Ying Han, Hanwen Chang, Shan Kan, Xuege Wang, Qiang Pan, Ping Wu, Chao Peng, Tong Qiu, Qintong Li, Dong Gao, Wei Xue, Jun Qin
Abstract
Tumor cure with conventional fractionated radiotherapy is 65%, dependent on tumor cell-autonomous gradual buildup of DNA double strand break (DSB) misrepair. Here we report single dose radiotherapy (SDRT), a disruptive technique that ablates >90% of human cancers, operates a distinct dual-target mechanism, linking acid sphingomyelinase (ASMase)-mediated microvascular perfusion defects to DNA unrepair in tumor cells to confer tumor cell lethality. ASMase-mediated microcirculatory vasoconstriction post-SDRT conferred an ischemic stress response within parenchymal tumor cells, with reactive oxygen species triggering the evolutionarily conserved SUMO Stress Response, specifically depleting chromatin-associated free SUMO3. Whereas SUMO3, but not SUMO2, was indispensible for homology-directed repair (HDR) of DSBs, HDR loss-of-function post-SDRT yielded DSB unrepair, chromosomal aberrations and tumor clonogen demise. Vasoconstriction blockade with the endothelin-1 inhibitor BQ-123, or ROS scavenging post-SDRT using peroxiredoxin-6 overexpression or the SOD-mimetic tempol, prevented chromatin SUMO3 depletion, HDR loss-of-function and SDRT tumor ablation. We also provide evidence of mouse to human translation of this biology in a randomized clinical trial, showing 24Gy SDRT, but not 3x9Gy fractionation, coupled early tumor ischemia/reperfusion to human cancer ablation. The SDRT biology provides opportunities for mechanism-based selective tumor radiosensitization via accessing SDRT/ASMase signaling, as current studies indicate this pathway is tractable to pharmacologic intervention.
Authors
Sahra Bodo, Cecile Campagne, Tin Htwe Thin, Daniel S. Higginson, H. Alberto Vargas, Guoqiang Hua, John D. Fuller, Ellen Ackerstaff, James Russell, Zhigang Zhang, Stefan Klingler, HyungJoon Cho, Matthew G. Kaag, Yousef Mazaheri, Andreas Rimner, Katia Manova-Todorova, Boris Epel, Joan Zatcky, Cristian R. Cleary, Shyam S. Rao, Yoshiya Yamada, Michael J. Zelefsky, Howard J. Halpern, Jason A. Koutcher, Carlos Cordon-Cardo, Carlo Greco, Adriana Haimovitz-Friedman, Evis Sala, Simon N. Powell, Richard Kolesnick, Zvi Fuks
Abstract
Abnormal alternative splicing (AS) caused by alterations of splicing factors contributes to tumor progression. Serine/arginine splicing factor 1 (SRSF1) has emerged as a key oncodriver in numerous solid tumors, leaving its roles and mechanisms largely obscure in glioma. Herein we demonstrated that SRSF1 was increased in glioma tissues and cell lines. Moreover, its expression was correlated positively with tumor grade and Ki-67 index, but inversely with patients’ survival. Using RNA-seq, we comprehensively screened and identified multiple SRSF1-affected AS events. Motif analysis revealed a position-dependent modulation of AS by SRSF1 in glioma. Functionally, we verified that SRSF1 promoted cell proliferation, survival and invasion by specifically switching the AS of myosin IB (MYO1B) gene and facilitating the expression of the oncogenic and membrane-localized isoform, MYO1B-fl. Strikingly, MYO1B splicing was dysregulated in parallel with SRSF1 expression in gliomas, and predicted the poor prognosis of the patients. Further investigation revealed that SRSF1-guided AS of MYO1B gene increased the tumorigenic potentials of glioma cells through the PDK1/AKT and PAK/LIMK pathways. Taken together, we identify SRSF1 as an important oncodriver, which integrates the AS controlling of MYO1B into promotion of gliomagenesis, and represents a potential prognostic biomarker and target for glioma therapy.
Authors
Xuexia Zhou, Run Wang, Xuebing Li, Lin Yu, Dan Hua, Cuiyun Sun, Cuijuan Shi, Wenjun Luo, Chun Rao, Zhendong Jiang, Ying Feng, Qian Wang, Shizhu Yu
Abstract
Recurrent broad-scale heterozygous deletions are frequently observed in human cancer. Here we tested the hypothesis that compound haploinsufficiency of neighboring genes at chromosome 8p promotes tumorigenesis. By targeting the mouse orthologs of human DOK2 and DUSP4 genes, which were co-deleted in approximately half of human lung adenocarcinomas, we found that compound-heterozygous deletion of Dok2 and Dusp4 in mice resulted in lung tumorigenesis with short latency and high incidence, and that their co-deletion synergistically activated MAPK signaling and promoted cell proliferation. Conversely, restoration of DOK2 and DUSP4 in lung cancer cells suppressed MAPK activation and cell proliferation. Importantly, in contrast to downregulation of DOK2 or DUSP4 alone, concomitant downregulation of DOK2 and DUSP4 was associated with poor survival in human lung adenocarcinoma. Therefore, our findings lend in vivo experimental support to the notion that compound haploinsufficiency, due to broad-scale chromosome deletions, constitutes a driving force in tumorigenesis.
Authors
Ming Chen, Jiangwen Zhang, Alice H. Berger, Moussa S. Diolombi, Christopher Ng, Jacqueline Fung, Roderick T. Bronson, Mireia Castillo-Martin, Tin Htwe Thin, Carlos Cordon-Cardo, Robin Plevin, Pier Paolo Pandolfi
Copyright © 2019 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)