DNASE1L3, an enzyme highly expressed in dendritic cells, is functionally important for regulating autoimmune responses to self-DNA and chromatin. Deficiency of DNASE1L3 leads to development of autoimmune diseases in both humans and mice. However, despite the well-established causal relationship between DNASE1L3 and immunity, little is known about the involvement of DNASE1L3 in regulation of anti-tumor immunity, the foundation of modern anti-tumor immunotherapy. In this study, we identify DNASE1L3 as a new regulator of anti-tumor immunity and a tumor suppressor in colon cancer. In humans, DNASE1L3 is downregulated in tumor-infiltrating dendritic cells, and this downregulation is associated with poor patient prognosis and reduced tumor immune cell infiltration in many cancer types. In mice, Dnase1l3 deficiency in the tumor microenvironment enhances tumor formation and growth in several colon cancer models. Notably, the increased tumor formation and growth in Dnase1l3-deficient mice are associated with impaired anti-tumor immunity, including a substantial reduction of cytotoxic T cells and a unique subset of dendritic cells. Consistently, Dnase1l3-deficient dendritic cells directly modulate cytotoxic T cells in vitro. Collectively, our study unveils a previously unknown link between DNASE1L3 and anti-tumor immunity, and further suggests that restoration of DNASE1L3 activity may represent a potential therapeutic approach for anti-cancer therapy.
Wenling Li, Hideki Nakano, Wei Fan, Yuanyuan Li, Payel Sil, Keiko Nakano, Fei Zhao, Peer W. Karmaus, Sara A. Grimm, Min Shi, Xin Xu, Ryushin Mizuta, Daisuke Kitamura, Yisong Wan, Michael B. Fessler, Donald N. Cook, Igor Shats, Xiaoling Li, Leping Li
Lysine-specific demethylase 1 (LSD1) is a histone demethylase that promotes stemness and cancer cell survival, including in prostate cancer. Most prostate malignancies are adenocarcinomas with luminal differentiation. However, some tumors undergo cellular reprogramming to a more lethal subset termed neuroendocrine prostate cancer (NEPC) with neuronal differentiation. The frequency of NEPC is increasing since widespread use of potent androgen receptor signaling inhibitors. Currently, there are no effective treatments for NEPC. We previously determined that LSD1 promotes survival of prostate adenocarcinoma tumors. However, the role of LSD1 in NEPC is unknown. Here, we determined that LSD1 is highly upregulated in NEPC vs. adenocarcinoma patient tumors. LSD1 suppression with RNAi or allosteric LSD1 inhibitors—but not catalytic inhibitors—reduced NEPC cell survival. RNA-seq analysis revealed that LSD1 represses pathways linked to luminal differentiation, and TP53 was the top reactivated pathway. We confirmed that LSD1 suppressed the TP53 pathway by reducing TP53 occupancy at target genes while LSD1’s catalytic function was dispensable for this effect. Mechanistically, LSD1 inhibition disrupted LSD1-HDAC interactions, increasing histone acetylation at TP53 targets. Finally, LSD1 inhibition suppressed NEPC tumor growth in vivo. These findings suggest that blocking LSD1’s non-catalytic function may be a promising new treatment strategy for NEPC.
Anbarasu Kumaraswamy, Zhi Duan, Diana Flores, Chao Zhang, Archana Sehrawat, Ya-Mei Hu, Olivia A. Swaim, Eva Rodansky, William K. Storck, Joshua A. Kuleape, Karan Bedi, Rahul Mannan, Xiao-Ming Wang, Aaron M. Udager, Visweswaran Ravikumar, Armand Bankhead III, Ilsa Coleman, John K. Lee, Colm Morrissey, Peter S. Nelson, Arul Chinnaiyan, Arvind Rao, Zheng Xia, Joel A. Yates, Joshi J. Alumkal
Glioblastomas (GBM) are aggressive tumors that lack effective treatments. Here, we show that the Rho family guanine nucleotide exchange factor Syx promotes GBM cell growth both in vitro and in orthotopic xenografts derived from patients with GBM. Growth defects upon Syx depletion are attributed to prolonged mitosis, increased DNA damage, G2/M cell cycle arrest, and cell apoptosis, mediated by altered mRNA and protein expression of various cell cycle regulators. These effects are phenocopied by depletion of the Rho downstream effector Dia1 and are due, at least in part, to increased phosphorylation, cytoplasmic retention, and reduced activity of the YAP/TAZ transcriptional coactivators. Furthermore, targeting Syx signaling cooperates with radiation treatment and temozolomide (TMZ) to decrease viability in GBM cells, irrespective of their inherent response to TMZ. The data indicate that a Syx-RhoA-Dia1-YAP/TAZ signaling axis regulates cell cycle progression, DNA damage, and therapy resistance in GBM and argue for its targeting for cancer treatment.
Wan-Hsin Lin, Ryan W. Feathers, Lisa M. Cooper, Laura J. Lewis-Tuffin, Jiaxiang Chen, Jann N. Sarkaria, Panos Z. Anastasiadis
Epigenetic aberrations, including posttranslational modifications of core histones, are major contributors to cancer. Here, we define the status of histone H2B monoubiquitylation (H2Bub1) in clear cell ovarian carcinoma (CCOC), low-grade serous carcinoma, and endometrioid carcinomas. We report that clear cell carcinomas exhibited profound loss, with nearly all cases showing low or negative H2Bub1 expression. Moreover, we found that H2Bub1 loss occurred in endometriosis and atypical endometriosis, which are established precursors to CCOCs. To examine whether dysregulation of a specific E3 ligase contributes to the loss of H2Bub1, we explored expression of ring finger protein 40 (RNF40), ARID1A, and UBR7 in the same case cohort. Loss of RNF40 was significantly and profoundly correlated with loss of H2Bub1. Using genome-wide DNA methylation profiles of 230 patients with CCOC, we identified hypermethylation of RNF40 in CCOC as a likely mechanism underlying the loss of H2Bub1. Finally, we demonstrated that H2Bub1 depletion promoted cell proliferation and clonogenicity in an endometriosis cell line. Collectively, our results indicate that H2Bub1 plays a tumor-suppressive role in CCOCs and that its loss contributes to disease progression.
Adam J. Ferrari, Priyanka Rawat, Hannah S. Rendulich, Akshaya V. Annapragada, Yasuto Kinose, Xiaoming Zhang, Kyle Devins, Anna Budina, Robert B. Scharpf, Marilyn A. Mitchell, Janos L. Tanyi, Mark A. Morgan, Lauren E. Schwartz, T. Rinda Soong, Victor E. Velculescu, Ronny Drapkin
The omentum contains immune cell structures called milky spots that are niches for transcoelomic metastasis. It is difficult to remove the omentum completely, and there are no effective strategies to minimize the risk of colonization of preserved omental tissues by cancer cells that circulate in the peritoneal fluid. Normal saline is commonly administered into the peritoneal cavity for diagnostic and intraoperative lavage. Here we show that normal saline, when administered into the peritoneal cavity of mice, is prominently absorbed by the omentum, exfoliates its mesothelium, and induces expression of CX3CL1, the ligand for CX3CR1, within and surrounding the omental vasculature. Studies using CX3CR1-competent and CX3CR1-deficient mice showed that the predominant response in the omentum following saline administration is an accumulation of CX3CR1+ monocytes/macrophages that expand milky spots and promote neoangiogenesis within these niches. Moreover, saline administration promoted the implantation of cancer cells of ovarian and colorectal origin onto the omentum. By contrast, these deleterious effects were not observed following i.p. administration of lactated Ringer’s solution. Our findings suggest that normal saline stimulates the receptivity of the omentum for cancer cells and that the risk of colonization can be minimized by using a biocompatible crystalloid for lavage procedures.
Hironari Akasaka, WonJae Lee, Song Yi Ko, Ernst Lengyel, Honami Naora
Vincristine is a widely used chemotherapeutic drug for the treatment of multiple malignant diseases that causes a dose-limiting peripheral neurotoxicity. There is no clinically effective preventative treatment for vincristine-induced sensory peripheral neurotoxicity (VIPN), and mechanistic details of this side effect remain poorly understood. We hypothesized that VIPN is dependent on transporter-mediated vincristine accumulation in dorsal root ganglion neurons. Using a xenobiotic transporter screen, we identified OATP1B3 as a neuronal transporter regulating the uptake of vincristine. In addition, genetic or pharmacological inhibition of the murine orthologue transporter OATP1B2 protected mice from various hallmarks of VIPN, including mechanical-induced allodynia, thermal hyperalgesia, and changes in digital maximal action potential amplitudes and neuronal morphology, without negatively affecting plasma levels or antitumor effects of vincristine. Finally, we identified α-tocopherol from an untargeted metabolomics analysis as a circulating endogenous biomarker of neuronal OATP1B2 function, which could serve as a future companion diagnostic to guide dose selection of OATP1B-type transport modulators given in combination with vincristine to prevent VIPN. Collectively, our findings shed light on the fundamental basis of VIPN and provide a rationale for the clinical development of transporter inhibitors to prevent this debilitating side effect.
Yang Li, Thomas Drabison, Mahesh Nepal, Richard H. Ho, Alix F. Leblanc, Alice A. Gibson, Yan Jin, Wenjian Yang, Kevin M. Huang, Muhammad Erfan Uddin, Mingqing Chen, Duncan F. DiGiacomo, Xihui Chen, Sobia Razzaq, Jeffrey R. Tonniges, Dana M. McTigue, Alice S. Mims, Maryam B. Lustberg, Yijia Wang, Amanda B. Hummon, William E. Evans, Sharyn D. Baker, Guido Cavaletti, Alex Sparreboom, Shuiying Hu
The RNA-binding protein LIN28B is overexpressed in over 30% of patients with colorectal cancer (CRC) and is associated with poor prognosis. In the present study, we unravel a novel mechanism by which LIN28B regulates colonic epithelial cell-cell junctions and CRC metastasis. Using human CRC cells (DLD-1, Caco-2 and LoVo) with either knockdown or overexpression of LIN28B, we identified Claudin 1 (CLDN1) tight junction protein as a direct downstream target and effector of LIN28B. RNA immunoprecipitation revealed that LIN28B directly binds to and post-transcriptionally regulates CLDN1 mRNA. Furthermore, using in vitro assays and a novel murine model of metastatic CRC, we show that LIN28B-mediated CLDN1 expression enhances collective invasion, cell migration, and metastatic liver tumor formation. Bulk RNA-sequencing of the metastatic liver tumors identified NOTCH3 as a downstream effector of the LIN28B-CLDN1 axis. Additionally, genetic and pharmacologic manipulation of NOTCH3 signaling revealed that NOTCH3 was necessary for invasion and metastatic liver tumor formation. In summary, our results suggest that LIN28B promotes invasion and liver metastasis of CRC by post-transcriptionally regulating CLDN1 and activating NOTCH3 signaling. This discovery offers a promising new therapeutic option for metastatic CRC to the liver, an area where therapeutic advancements have been relatively scarce.
Kensuke Sugiura, Yasunori Masuike, Kensuke Suzuki, Alice E. Shin, Nozomu Sakai, Hisahiro Matsubara, Masayuki Ohtsuka, Peter A. Sims, Christopher J. Lengner, Anil K. Rustgi
Radiation therapy is an effective cancer treatment although damages to healthy tissues are common. Here we analyzed cell-free, methylated DNA released from dying cells into the circulation to evaluate radiation-induced cellular damages in different tissues. To map the circulating DNA fragments to human and mouse tissues, we established sequencing-based, cell-type specific reference DNA methylation atlases. We found that cell-type specific DNA blocks were mostly hypomethylated and located within signature genes of cellular identity. Cell-free DNA fragments were captured from serum samples by hybridization to CpG-rich DNA panels and mapped to the DNA methylation atlases. In a mouse model, thoracic radiation-induced tissue damages were reflected by dose-dependent increases in lung endothelial and cardiomyocyte methylated DNA in serum. The analysis of serum samples from breast cancer patients undergoing radiation treatment revealed distinct dose-dependent and tissue-specific epithelial and endothelial responses to radiation across multiple organs. Strikingly, patients treated for right-sided breast cancers also showed increased hepatocyte and liver endothelial DNA in the circulation indicating the impact on liver tissues. Thus, changes in cell-free methylated DNA can uncover cell-type specific effects of radiation and provide a readout of the biologically effective radiation dose received by healthy tissues.
Megan E. McNamara, Netanel Loyfer, Amber J. Kiliti, Marcel O. Schmidt, Sapir Shabi-Porat, Sidharth S. Jain, Sarah Martinez Roth, A. Patrick McDeed IV, Nesreen Shahrour, Elizabeth Ballew, Yun-Tien Lin, Heng-Hong Li, Anne Deslattes Mays, Sonali Rudra, Anna T. Riegel, Keith Unger, Tommy Kaplan, Anton Wellstein
Forkhead box M1 (FOXM1) plays a critical role in development physiologically and tumorigenesis pathologically. However, insufficient efforts have been dedicated to exploring the regulation, in particular the degradation of FOXM1. Here, the ON-TARGETplus siRNA library targeting E3 ligases was used to screen potential candidates to repress FOXM1. Of note, mechanism study revealed that RNF112 directly ubiquitinates FOXM1 in gastric cancer, resulting in a decreased FOXM1 transcriptional network and suppressing the proliferation and invasion of gastric cancer. Interestingly, the well-established small-molecule compound RCM-1 significantly enhanced the interaction between RNF112 and FOXM1, which further promoted FOXM1 ubiquitination and subsequently exerted promising anticancer effects in vitro and in vivo. Altogether, we demonstrate that RNF112 suppresses gastric cancer progression by ubiquitinating FOXM1 and highlight the RNF112/FOXM1 axis serves as both prognosis biomarker and therapeutic target in gastric cancer.
Shengwei Zhang, Jing Wang, Weichao Hu, Lijiao He, Qingyun Tang, Jie Li, Mengmeng Jie, Xinzhe Li, Cheng Liu, Qin Ouyang, Shiming Yang, Changjiang Hu
Osteosarcoma (OS) is the most common primary bone tumor of childhood. Approximately 20-30% of OS carry amplification of chromosome 8q24, which harbors the oncogene c-Myc and correlates with a poor prognosis. To understand the mechanisms that underlie the ability of Myc to alter both the tumor and its surrounding tumor microenvironment (TME), we generated and molecularly characterized an osteoblast-specific Cre-Lox-Stop-Lox;(LSL)-c-MycT58A;p53fl/+ knock-in genetically engineered mouse model (GEMM). Phenotypically, the Myc knockin-GEMM had rapid tumor development with a high incidence of metastasis. Myc-dependent gene signatures in our murine model demonstrated significant homology to the human hyperactivated Myc OS. We established that hyperactivation of Myc leads to an immune-depleted TME in OS demonstrated by the reduced number of leukocytes, particularly macrophages. Myc-hyperactivation leads to the downregulation of macrophage-colony-stimulating factor (CSF-1), through increased miR-17/20a expression, causing a reduction of macrophage population in the TME of OS. Furthermore, we developed cell lines from the GEMM tumors, including a dTAG-Myc model system, which validated our Myc-dependent findings both in vitro and in vivo. Our studies utilized innovative, and clinically relevant models to identify a novel molecular mechanism through which Myc regulates the profile and function of the osteosarcoma immune landscape.
Bikesh K. Nirala, Tajhal D. Patel, Lyazat Kurenbekova, Ryan Shuck, Atreyi Dasgupta, Nino Rainusso, Cristian Coarfa, Jason T. Yustein
No posts were found with this tag.