Several canonical translocations produce oncofusion genes that can initiate Acute Myeloid Leukemia (AML). Although each translocation is associated with unique features, the mechanisms responsible remain unclear. While proteins interacting with each oncofusion are known to be relevant for how they act, these interactions have not yet been systematically defined. To address this issue in an unbiased fashion, we fused a promiscuous biotin ligase ("TurboID") in-frame with three favorable-risk acute myeloid leukemia (AML) oncofusion cDNAs (PML::RARA, RUNX1::RUNX1T1, and CBFB::MYH11), and identified their interacting proteins in primary murine hematopoietic cells. The PML::RARA- and RUNX1::RUNX1T1-TurboID fusion proteins labeled common and unique nuclear repressor complexes, implying their nuclear localization. However, CBFB::MYH11-TurboID interacting proteins were largely cytoplasmic, probably due to an interaction of the MYH11 domain with several cytoplasmic myosin-related proteins. Using a variety of methods, we showed that the CBFB domain of CBFB::MYH11 sequesters RUNX1 in cytoplasmic aggregates; these findings were confirmed in primary human AML cells. Paradoxically, CBFB::MYH11 expression was associated with increased RUNX1/2 expression, suggesting the presence of a sensor for reduced functional RUNX1 protein, and a feedback loop that that may attempt to compensate by increasing RUNX1/2 transcription. These findings may have broad implications for AML pathogenesis.
Ryan B. Day, Julia A. Hickman, Ziheng Xu, Casey D.S. Katerndahl, Francesca Ferraro, Sai Mukund Ramakrishnan, Petra Erdmann-Gilmore, Robert W. Sprung, Yiling Mi, R. Reid Townsend, Christopher A. Miller, Timothy J. Ley
Microscopic hemorrhage is a common aspect of cancers, yet its potential role as an independent factor influencing both cancer progression and therapeutic response is largely ignored. Recognizing the essential function of macrophages in red blood cell disposal, we explored a pathway that connects intratumoral hemorrhage with the formation of cancer-promoting tumor-associated macrophages (TAMs). Using spatial transcriptomics, we found that NRF2-activated myeloid cells possessing characteristics of procancerous TAMs tend to cluster in peri-necrotic hemorrhagic tumor regions. These cells resembled anti-inflammatory erythrophagocytic macrophages. We identified heme, a red blood cell metabolite, as a pivotal microenvironmental factor steering macrophages toward protumorigenic activities. Single-cell RNA-seq and functional assays of TAMs in 3D cell culture spheroids revealed how elevated intracellular heme signals via the transcription factor NRF2 to induce cancer-promoting TAMs. These TAMs stabilized epithelial-mesenchymal transition, enhancing cancer invasiveness and metastatic potential. Additionally, NRF2-activated macrophages exhibited resistance to reprogramming by IFNγ and anti-CD40 antibodies, reducing their tumoricidal capacity. Furthermore, MC38 colon adenocarcinoma-bearing mice with NRF2 constitutively activated in leukocytes were resistant to anti-CD40 immunotherapy. Overall, our findings emphasize hemorrhage-activated NRF2 in TAMs as a driver of cancer progression, suggesting that targeting this pathway could offer new strategies to enhance cancer immunity and overcome therapy resistance.
Dominik J. Schaer, Nadja Schulthess-Lutz, Livio Baselgia, Kerstin Hansen, Raphael M. Buzzi, Rok Humar, Elena Dürst, Florence Vallelian
Acute myeloid leukemia (AML) presents a pressing medical need in that it is largely resistant to standard chemotherapy as well as modern therapeutics such as targeted therapy and immunotherapy, including anti-PD therapy. We demonstrate that Programmed Death-1 Homolog (PD-1H), an immune co-inhibitory molecule is highly expressed in blasts from the bone marrow of AML patients, while normal myeloid cell subsets and T cells have the expression of PD-1H. In studies employing syngeneic and humanized AML mouse models, overexpression of PD-1H promoted the growth of AML cells, mainly by evading T cell-mediated immune responses. Importantly, ablation of AML cell surface PD-1H by antibody blockade or genetic targeting significantly inhibited AML progression by promoting T cell activity. In addition, the genetic deletion of PD-1H from host normal myeloid cells inhibited AML progression as well and the combination of PD-1H blockade with PD-1 blockade conferred a synergistic anti-leukemia effect. Our findings provide the basis for PD-1H as an attractive therapeutic target to treat human AML.
Tae Kon Kim, Xue Han, Qianni Hu, Esten N. Vandsemb, Carly M. Fielder, Junshik Hong, Kwang Woon Kim, Emily F. Mason, R. Skipper Plowman, Jun Wang, Qi Wang, Jian-Ping Zhang, Ti Badri, Miguel F. Sanmamed, Linghua Zheng, Tianxiang Zhang, Jude Alawa, Sang Won Lee, Amer M. Zeidan, Stephanie Halene, Manoj M. Pillai, Namrata S. Chandhok, Jun Lu, Mina L. Xu, Steven D. Gore, Lieping Chen
Oxygen and nutrient deprivation is a common feature of solid tumours. Although abnormal alternative splicing (AS) has been found to be a new driving force in tumour pathogenesis and progression, the regulatory mechanisms of AS underlying the adaptation of cancer cells to harsh microenvironments remain unclear. Here, we found that hypoxia- and nutrient deprivation-induced asparagine endopeptidase (AEP) specifically cleaves DDX3X in a HIF1A-dependent manner. This cleavage yields truncated carboxyl-terminal DDX3X (tDDX3X-C), which translocates and aggregates in the nucleus. Unlike intact DDX3X, nuclear tDDX3X-C complexes with an array of splicing factors and induces AS events of many pre-mRNAs; for example, enhanced exon skipping (ES) in exon 2 of the classic tumour suppressor PRDM2 leads to a frameshift mutation of PRDM2. Intriguingly, the novel isoform ARRB1△exon13 binds to glycolytic enzymes and regulates glycolysis. By utilizing in vitro assays, glioblastoma organoids and animal models, we revealed that AEP/tDDX3X-C promotes tumour malignancy via these isoforms. More importantly, high AEP/tDDX3X-C/ARRB1△exon13 in cancerous tissues was tightly associated with poor patient prognosis. Overall, our discovery of the effect of AEP-cleaved DDX3X switching on alternative RNA splicing events identifies a new mechanism in which cancer cells adapt to oxygen/nutrient shortages and provides novel diagnostic/therapeutic targets.
Wenrui Zhang, Lu Cao, Jian Yang, Shuai Zhang, Jianyi Zhao, Zhonggang Shi, Keman Liao, Haiwei Wang, Binghong Chen, Zhongrun Qian, Haoping Xu, Linshi Wu, Hua Liu, Hongxiang Wang, Chunhui Ma, Yongming Qiu, Jianwei Ge, Jiayi Chen, Yingying Lin
While the poor prognosis of glioblastoma arises from the invasion of a subset of tumor cells, little is known of the metabolic alterations within these cells that fuel invasion. We integrated spatially addressable hydrogel biomaterial platforms, patient site-directed biopsies, and multi-omics analyses to define metabolic drivers of invasive glioblastoma cells. Metabolomics and lipidomics revealed elevations in the redox buffers cystathionine, hexosylceramides, and glucosyl ceramides in the invasive front of both hydrogel-cultured tumors and patient site-directed biopsies, with immunofluorescence indicating elevated reactive oxygen species (ROS) markers in invasive cells. Transcriptomics confirmed upregulation of ROS-producing and response genes at the invasive front in both hydrogel models and patient tumors. Amongst oncologic ROS, H2O2 specifically promoted glioblastoma invasion in 3D hydrogel spheroid cultures. A CRISPR metabolic gene screen revealed cystathionine gamma-lyase (CTH), which converts cystathionine to the non-essential amino acid cysteine in the transsulfuration pathway, to be essential for glioblastoma invasion. Correspondingly, supplementing CTH knockdown cells with exogenous cysteine rescued invasion. Pharmacologic CTH inhibition suppressed glioblastoma invasion, while CTH knockdown slowed glioblastoma invasion in vivo. Our studies highlight the importance of ROS metabolism in invasive glioblastoma cells and support further exploration of the transsulfuration pathway as a mechanistic and therapeutic target.
Joseph H. Garcia, Erin A. Akins, Saket Jain, Kayla J. Wolf, Jason Zhang, Nikita Choudhary, Meeki Lad, Poojan Shukla, Jennifer Rios, Kyounghee Seo, Sabraj A. Gill, William H. Carson, Luis R. Carrete, Allison C. Zheng, David R. Raleigh, Sanjay Kumar, Manish K. Aghi
Prostate cancer is generally considered an immunologically “cold” tumor type that is insensitive to immunotherapy. Targeting surface antigens on tumors through cellular therapy can induce a potent antitumor immune response to “heat up” the tumor microenvironment. However, many antigens expressed on prostate tumor cells are also found on normal tissues, potentially causing on-target, off-tumor toxicities and a suboptimal therapeutic index. Our studies revealed that six-transmembrane epithelial antigen of prostate-2 (STEAP2) was a prevalent prostate cancer antigen that displayed high, homogeneous cell surface expression across all stages of disease with limited distal normal tissue expression, making it ideal for therapeutic targeting. A multifaceted lead generation approach enabled development of an armored STEAP2 chimeric antigen receptor T cell (CAR-T) therapeutic candidate, AZD0754. This CAR-T product was armored with a dominant-negative TGF-β type II receptor, bolstering its activity in the TGF-β–rich immunosuppressive environment of prostate cancer. AZD0754 demonstrated potent and specific cytotoxicity against antigen-expressing cells in vitro despite TGF-β–rich conditions. Further, AZD0754 enforced robust, dose-dependent in vivo efficacy in STEAP2-expressing cancer cell line–derived and patient-derived xenograft mouse models, and exhibited encouraging preclinical safety. Together, these data underscore the therapeutic tractability of STEAP2 in prostate cancer as well as build confidence in the specificity, potency, and tolerability of this potentially first-in-class CAR-T therapy.
Peter Zanvit, Dewald van Dyk, Christine Fazenbaker, Kelly McGlinchey, Weichuan Luo, Jessica M. Pezold, John Meekin, Chien-ying Chang, Rosa A. Carrasco, Shannon Breen, Crystal Sao-Fong Cheung, Ariel Endlich-Frazier, Benjamin Clark, Nina J. Chu, Alessio Vantellini, Philip L. Martin, Clare E. Hoover, Kenesha Riley, Steve M. Sweet, David Chain, Yeoun Jin Kim, Eric Tu, Nathalie Harder, Sandrina Phipps, Melissa Damschroder, Ryan N. Gilbreth, Mark Cobbold, Gordon Moody, Emily E. Bosco
Effective eradication of leukemic stem cells (LSCs) remains the greatest challenge in treating acute myeloid leukemia (AML). The immune receptor LAIR-1 has been shown to regulate LSC survival; however, the therapeutic potential of this pathway remains unexplored. We developed a therapeutic LAIR-1 agonist antibody, NC525, that induced cell death of LSCs, but not healthy hematopoietic stem cells in vitro, and killed LSCs and AML blasts in both cell- and patient-derived xenograft models. We showed that LAIR-1 agonism drives a unique apoptotic signaling program in leukemic cells that was enhanced in the presence of collagen. NC525 also significantly improved the activity of azacitidine and venetoclax to establish LAIR-1 targeting as a therapeutic strategy for AML that may synergize with standard-of-care therapies.
Rustin R. Lovewell, Junshik Hong, Subhadip Kundu, Carly M. Fielder, Qianni Hu, Kwang Woon Kim, Haley E. Ramsey, Agnieszka E. Gorska, Londa S. Fuller, Linjie Tian, Priyanka Kothari, Ana Paucarmayta, Emily F. Mason, Ingrid Meza, Yanira Manzanarez, Jason Bosiacki, Karla Maloveste, Ngan Mitchell, Emilia A. Barbu, Aaron Morawski, Sebastien Maloveste, Zac Cusumano, Shashank J. Patel, Michael R. Savona, Solomon Langermann, Han Myint, Dallas B. Flies, Tae Kon Kim
The heterogeneity of cancer stem cells (CSCs) within tumors presents a challenge in therapeutic targeting. To decipher the cellular plasticity that fuels phenotypic heterogeneity, we undertook single-cell transcriptomics analysis in triple-negative breast cancer (TNBC) to identify subpopulations in CSCs. We found a subpopulation of CSCs with ancestral features that is marked by FXYD domain–containing ion transport regulator 3 (FXYD3), a component of the Na+/K+ pump. Accordingly, FXYD3+ CSCs evolve and proliferate, while displaying traits of alveolar progenitors that are normally induced during pregnancy. Clinically, FXYD3+ CSCs were persistent during neoadjuvant chemotherapy, hence linking them to drug-tolerant persisters (DTPs) and identifying them as crucial therapeutic targets. Importantly, FXYD3+ CSCs were sensitive to senolytic Na+/K+ pump inhibitors, such as cardiac glycosides. Together, our data indicate that FXYD3+ CSCs with ancestral features are drivers of plasticity and chemoresistance in TNBC. Targeting the Na+/K+ pump could be an effective strategy to eliminate CSCs with ancestral and DTP features that could improve TNBC prognosis.
Mengjiao Li, Tatsunori Nishimura, Yasuto Takeuchi, Tsunaki Hongu, Yuming Wang, Daisuke Shiokawa, Kang Wang, Haruka Hirose, Asako Sasahara, Masao Yano, Satoko Ishikawa, Masafumi Inokuchi, Tetsuo Ota, Masahiko Tanabe, Kei-ichiro Tada, Tetsu Akiyama, Xi Cheng, Chia-Chi Liu, Toshinari Yamashita, Sumio Sugano, Yutaro Uchida, Tomoki Chiba, Hiroshi Asahara, Masahiro Nakagawa, Shinya Sato, Yohei Miyagi, Teppei Shimamura, Luis Augusto E. Nagai, Akinori Kanai, Manami Katoh, Seitaro Nomura, Ryuichiro Nakato, Yutaka Suzuki, Arinobu Tojo, Dominic C. Voon, Seishi Ogawa, Koji Okamoto, Theodoros Foukakis, Noriko Gotoh
Mutations in the BRCA2 tumor suppressor gene have been associated with an increased risk of developing prostate cancer. One of the paradoxes concerning BRCA2 is the fact that its inactivation affects genetic stability and is deleterious for cellular and organismal survival, while BRCA2-mutated cancer cells adapt to this detriment and malignantly proliferate. Therapeutic strategies for tumors arising from BRCA2 mutations may be discovered by understanding these adaptive mechanisms. In this study, we conducted forward genetic synthetic viability screenings in C. elegans brc-2 (Cebrc-2) mutants and found that Ceubxn-2 inactivation rescued the viability of Cebrc-2 mutants. Moreover, loss of NSFL1C, the mammalian ortholog of CeUBXN-2, suppressed the spindle assembly checkpoint (SAC) activation and promoted the survival of BRCA2-deficient cells. Mechanistically, NSFL1C recruited USP9X to inhibit the polyubiquitination of AURKB and reduce the removal of AURKB from the centromeres by VCP, which is essential for SAC activation. SAC inactivation is common in BRCA2-deficient prostate cancer patients, but PP2A inhibitors could reactivate the SAC and achieve BRCA2-deficient prostate tumor synthetic lethality. Our research reveals the survival adaptation mechanism of BRCA2-deficient prostate tumor cells and provides different angles for exploring synthetic lethal inhibitors in addition to targeting DNA damage repair pathways.
Jian Wang, Yuke Chen, Shiwei Li, Wanchang Liu, Xiao Albert Zhou, Yefei Luo, Zhanzhan Xu, Yundong Xiong, Kaiqi Cheng, Mingjian Ruan, Wei Yu, Xiaoman Li, Weibin Wang, Jiadong Wang
BACKGROUND. PATRIOT was the first-in-human phase I study of the oral ATR (ataxia telangiectasia and Rad3-related) inhibitor ceralasertib (AZD6738) in advanced solid tumors. METHODS. Primary objective was safety. Secondary objectives included assessment of anti-tumor responses, pharmacokinetic (PK) and pharmacodynamic (PD) studies. Sixty-seven patients received ceralasertib 20-240 mg BD continuously or intermittently (14 of a 28-day cycle). RESULTS. Intermittent dosing was better tolerated than continuous, which was associated with dose-limiting hematological toxicity. The recommended phase 2 dose of ceralasertib was 160 mg twice daily for 2 weeks in a 4-weekly cycle. Modulation of target and increased DNA damage were identified in tumor and surrogate PD. There were 5 (8%) confirmed partial responses (PR, 40-240 mg BD), 34 (52%) stable disease (SD) including 1 unconfirmed partial response, and 27 (41%) progressive disease. Durable responses were seen in tumors with loss of AT-rich interactive domain-containing protein 1A (ARID1A) and DNA damage response defects. Treatment modulated tumor and systemic immune markers and responding tumors were more immune-inflamed than non-responding. CONCLUSION. Ceralasertib monotherapy was tolerated at 160 mg BD intermittent and associated with anti-tumor activity. TRIAL REGISTRATION. Clinicaltrials.gov: NCT02223923, EudraCT: 2013-003994-84. FUNDING. Cancer Research UK, AstraZeneca, UK Department of Health (National Institute for Health Research), Rosetrees Trust, Experimental Cancer Medicine Centre. FUNDING. AstraZeneca provided funding for components of the clinical conduct of PATRIOT and drug supply and labelling.
Magnus T. Dillon, Jeane Guevara, Kabir Mohammed, Emmanuel Christian Patin, Simon A. Smith, Emma Dean, Gemma N. Jones, Sophie E. Willis, Marcella Petrone, Carlos Silva, Khin Thway, Catey Bunce, Ioannis Roxanis, Pablo Nenclares, Anna Wilkins, Martin McLaughlin, Adoracion Jayme-Laiche, Sarah Benafif, Georgios Nintos, Vineet Kwatra, Lorna Grove, David C. Mansfield, Paula Proszek, Philip Martin, Luiza Moore, Karen E. Swales, Udai Banerji, Mark P. Saunders, James Spicer, Martin D. Forster, Kevin J. Harrington