{"title":"Discovery of RGT-018: a Potent, Selective and Orally Bioavailable SOS1 Inhibitor for KRAS-driven Cancers.","authors":"Fei Xiao, Kailiang Wang, Xinjuan Wang, Huijuan Li, Zhilong Hu, Xiaoming Ren, Wei Huang, Teng Feng, Lili Yao, Jing Lin, Chunlai Li, Zhuanzhuan Zhang, Liufeng Mei, Xiaotian Zhu, Wenge Zhong, Zhi Xie","doi":"10.1158/1535-7163.MCT-24-0049","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0049","url":null,"abstract":"<p><p>KRAS is the most frequently dysregulated oncogene with high prevalence in NSCLC, colorectal cancer, and pancreatic cancer. FDA-approved sotorasib and adagrasib provide breakthrough therapies for cancer patients with KRASG12C mutation. However, there is still high unmet medical need for new agents targeting broader KRAS-driven tumors. An emerging and promising opportunity is to develop a pan KRAS inhibitor by suppressing the upstream protein SOS1. SOS1 is a key activator of KRAS and facilitates the conversion of GDP-bound KRAS state to GTP-bound KRAS state. Binding to its catalytic domain, small molecule SOS1 inhibitor has demonstrated the ability to suppress KRAS activation and cancer cell proliferation. RGT-018, a potent and selective SOS1 inhibitor, was identified with optimal drug-like properties. In vitro, RGT-018 blocked the interaction of KRAS:SOS1 with single digit nM potency and is highly selective against SOS2. RGT-018 inhibited KRAS signaling and the proliferation of a broad spectrum of KRAS-driven cancer cells as a single agent in vitro. Further enhanced anti-proliferation activity was observed when RGT-018 was combined with MEK, KRASG12C, EGFR or CDK4/6 inhibitors. Oral administration of RGT-018 inhibited tumor growth and suppressed KRAS signaling in tumor xenografts in vivo. Combination with MEK or KRASG12C inhibitors led to significant tumor regression. Furthermore, RGT-018 overcame the resistance to the approved KRASG12C inhibitors caused by clinically acquired KRAS mutations either as a single agent or in combination. RGT-018 displayed promising pharmacological properties for combination with targeted agents to treat a broader KRAS-driven patient population.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141860321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Gregory S Parker, Julia I Toth, Sarah Fish, Gabrielle Blanco, Taylor Kampert, Xiaoming Li, Linette Yang, Craig R Stumpf, Kenneth Steadman, Aleksandar Jamborcic, Stephen Chien, Elizabeth Daniele, Alejandro Dearie, Geoffray Leriche, Simon Bailey, Peggy A Thompson
{"title":"Discovery of Monovalent Direct Degraders of BRD4 that Act via the Recruitment of DCAF11.","authors":"Gregory S Parker, Julia I Toth, Sarah Fish, Gabrielle Blanco, Taylor Kampert, Xiaoming Li, Linette Yang, Craig R Stumpf, Kenneth Steadman, Aleksandar Jamborcic, Stephen Chien, Elizabeth Daniele, Alejandro Dearie, Geoffray Leriche, Simon Bailey, Peggy A Thompson","doi":"10.1158/1535-7163.MCT-24-0219","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0219","url":null,"abstract":"<p><p>Targeted protein degradation (TPD) using the ubiquitin proteasome system (UPS) is a rapidly growing drug discovery modality to eliminate pathogenic proteins. Strategies for TPD have focused on heterobifunctional degraders that often suffer from poor drug-like properties, and molecular glues that rely on serendipitous discovery. Monovalent \"direct\" degraders represent an alternative approach, in which small molecules bind to a target protein and induce degradation of that protein through the recruitment of an E3 ligase complex. Using an ultra-high throughput cell-based screening platform, degraders of the bromodomain extraterminal protein BRD4 were identified and optimized to yield a lead compound, PLX-3618. In this paper, we demonstrate that PLX-3618 elicited UPS-mediated selective degradation of BRD4, resulting in potent antitumor activity in vitro and in vivo. Characterization of the degradation mechanism identified DCAF11 as the E3 ligase required for PLX-3618-mediated degradation of BRD4. Protein-protein interaction studies verified a BRD4:PLX-3618:DCAF11 ternary complex, and mutational studies provided further insights into the DCAF11-mediated degradation mechanism. Collectively, these results demonstrate the discovery and characterization of a novel small molecule that selectively degrades BRD4 through the recruitment of the E3 substrate receptor, DCAF11, and promotes potent antitumor activity in vivo.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"OF1-OF13"},"PeriodicalIF":5.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141534847","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alejandro A Puchol Tarazona, Alexander Schinagl, Irina Mirkina, Gregor Rossmueller, Randolf J Kerschbaumer, Friedmund Bachmann, Michael Thiele
{"title":"Pretargeted Radioimmunotherapy with the Novel Anti-oxMIF/HSG Bispecific Antibody ON105 Results in Significant Tumor Regression in Murine Models of Cancer.","authors":"Alejandro A Puchol Tarazona, Alexander Schinagl, Irina Mirkina, Gregor Rossmueller, Randolf J Kerschbaumer, Friedmund Bachmann, Michael Thiele","doi":"10.1158/1535-7163.MCT-24-0083","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0083","url":null,"abstract":"<p><p>Radioimmunotherapy (RIT) uses monoclonal antibodies to deliver radionuclides to cancer cells or the tumor microenvironment and has shown promise in treating localized and diffuse tumors. Although RIT agents have gained FDA/EMA approval for certain hematologic malignancies, effectiveness of RIT in treating solid tumors remains limited. In this study, we present PreTarg-it®, a novel approach for pretargeted RIT, providing optimized delivery of payloads in a two-step regimen. The effectiveness of PreTarg-it® is demonstrated by a powerful combination of ON105, a novel bispecific antibody against both oxidized macrophage migration inhibitory factor (oxMIF) and the histamine-succinyl-glycyl (HSG) hapten, as the first component and the radioactively labeled DOTA-di-HSG peptide as the second component in murine models of cancer. Mice bearing either subcutaneous mouse colorectal CT26 or human pancreatic CFPAC-1 tumors received an i.v. injection of ON105. After ON105 had accumulated in the tumor and cleared from circulation to approximately 1% to 3% of its peak concentration, 177Lu-DOTA-di-HSG peptide was administered. A single PreTarg-it® treatment cycle resulted in tumor regression when mice bearing CT26 tumors were given the highest treatment dose with a pretargeting delay of 3 days. Administered with a 5-day interval, the highest dose arrested tumor growth in both CT26 syngrafts and CFPAC-1 xenografts. In all cases, the highest treatment dose resulted in 100% survival at the study endpoint, whereas the control cohorts showed 0% and 60% survival in the CT26 and CFPAC-1 models, respectively. Therefore, PreTarg-it® holds potential as a novel and potent therapy for patients with hard-to-treat solid tumors, such as pancreatic cancer, as well as those with late-stage malignancies.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"OF1-OF11"},"PeriodicalIF":5.3,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141498501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ultrasensitive Response Explains the Benefit of Combination Chemotherapy Despite Drug Antagonism.","authors":"Sarah C Patterson, Amy E Pomeroy, Adam C Palmer","doi":"10.1158/1535-7163.MCT-23-0642","DOIUrl":"10.1158/1535-7163.MCT-23-0642","url":null,"abstract":"<p><p>Most aggressive lymphomas are treated with combination chemotherapy, commonly as multiple cycles of concurrent drug administration. Concurrent administration is in theory optimal when combination therapies have synergistic (more than additive) drug interactions. We investigated pharmacodynamic interactions in the standard 4-drug \"CHOP\" regimen in peripheral T-cell lymphoma (PTCL) cell lines and found that CHOP consistently exhibits antagonism and not synergy. We tested whether staggered treatment schedules could improve tumor cell kill by avoiding antagonism, using in vitro models of concurrent or staggered treatments. Surprisingly, we observed that tumor cell kill is maximized by concurrent drug administration despite antagonistic drug-drug interactions. We propose that an ultrasensitive dose response, as described in radiology by the linear-quadratic (LQ) model, can reconcile these seemingly contradictory experimental observations. The LQ model describes the relationship between cell survival and dose, and in radiology has identified scenarios favoring hypofractionated radiotherapy-the administration of fewer large doses rather than multiple smaller doses. Specifically, hypofractionated treatment can be favored when cells require an accumulation of DNA damage, rather than a \"single hit,\" to die. By adapting the LQ model to combination chemotherapy and accounting for tumor heterogeneity, we find that tumor cell kill is maximized by concurrent administration of multiple drugs, even when chemotherapies have antagonistic interactions. Thus, our study identifies a new mechanism by which combination chemotherapy can be clinically beneficial that is not contingent on positive drug-drug interactions.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"995-1009"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11219261/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140288567","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ukhyun Jo, Yasuhiro Arakawa, Astrid Zimmermann, Daiki Taniyama, Makito Mizunuma, Lisa M Jenkins, Tapan Maity, Suresh Kumar, Frank T Zenke, Naoko Takebe, Yves Pommier
{"title":"The Novel ATR Inhibitor M1774 Induces Replication Protein Overexpression and Broad Synergy with DNA-targeted Anticancer Drugs.","authors":"Ukhyun Jo, Yasuhiro Arakawa, Astrid Zimmermann, Daiki Taniyama, Makito Mizunuma, Lisa M Jenkins, Tapan Maity, Suresh Kumar, Frank T Zenke, Naoko Takebe, Yves Pommier","doi":"10.1158/1535-7163.MCT-23-0402","DOIUrl":"10.1158/1535-7163.MCT-23-0402","url":null,"abstract":"<p><p>Ataxia telangiectasia and Rad3-related (ATR) checkpoint kinase inhibitors are in clinical trials. Here we explored the molecular pharmacology and therapeutic combination strategies of the oral ATR inhibitor M1774 (Tuvusertib) with DNA-damaging agents (DDA). As single agent, M1774 suppressed cancer cell viability at nanomolar concentrations, showing greater activity than ceralasertib and berzosertib, but less potency than gartisertib and elimusertib in the small cell lung cancer H146, H82, and DMS114 cell lines. M1774 also efficiently blocked the activation of the ATR-CHK1 checkpoint pathway caused by replication stress induced by TOP1 inhibitors. Combination with non-toxic dose of M1774 enhanced TOP1 inhibitor-induced cancer cell death by enabling unscheduled replication upon replicative damage, thereby increasing genome instability. Tandem mass tag-based quantitative proteomics uncovered that M1774, in the presence of DDA, forces the expression of proteins activating replication (CDC45) and G2-M progression (PLK1 and CCNB1). In particular, the fork protection complex proteins (TIMELESS and TIPIN) were enriched. Low dose of M1774 was found highly synergistic with a broad spectrum of clinical DDAs including TOP1 inhibitors (SN-38/irinotecan, topotecan, exatecan, and exatecan), the TOP2 inhibitor etoposide, cisplatin, the RNA polymerase II inhibitor lurbinectedin, and the PARP inhibitor talazoparib in various models including cancer cell lines, patient-derived organoids, and mouse xenograft models. Furthermore, we demonstrate that M1774 reverses chemoresistance to anticancer DDAs in cancer cells lacking SLFN11 expression, suggesting that SLFN11 can be utilized for patient selection in upcoming clinical trials.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"911-923"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11555614/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140102031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characteristics of Carcinoembryonic Antigen-Related Cell Adhesion Molecules and Their Relationship to Cancer.","authors":"Ru-Xue Ma, Jian-Rui Wei, Yan-Wei Hu","doi":"10.1158/1535-7163.MCT-23-0461","DOIUrl":"10.1158/1535-7163.MCT-23-0461","url":null,"abstract":"<p><p>Carcinoembryonic antigen-related cell adhesion molecules (CEACAM), such as carcinoembryonic antigen (CEA) and the oncofetal glycoprotein family, are tumor markers. The CEACAMs consist of 12 different human CEACAMs and 5 different murine CEACAMs. The CEACAM family of proteins participates in multiple biological processes that include the immune response, angiogenesis, and cancer. CEACAMs play a significant role in cancer initiation and development. Increasing evidence suggests that family members may be new cancer biomarkers and targets in that CEACEAMs tend to be aberrantly expressed and therefore may have potential diagnostic and therapeutic importance. This review systematically summarizes the biogenesis, biological properties, and functions of CEACAMs, with a focus on their relationship with cancer and potential clinical application. As our knowledge of the relationships among CEACAMs and cancer increases, and as our understanding of the involved molecular mechanisms improves, new therapeutic strategies will evolve for cancer prevention and treatment of patients with cancer.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"939-948"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140137034","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Joshua P Plotnik, Adam E Richardson, Haopeng Yang, Estela Rojas, Velitchka Bontcheva, Colleen Dowell, Sydney Parsons, Ashley Wilson, Vida Ravanmehr, Christine Will, Paul Jung, Haizhong Zhu, Sarathy Karunan Partha, Sanjay C Panchal, Raghuveer Singh Mali, Frederick J Kohlhapp, Ryan A McClure, Cyril Y Ramathal, Mariam D George, Manisha Jhala, Nathaniel L Elsen, Wei Qiu, Russell A Judge, Chin Pan, Anthony Mastracchio, Jared Henderson, Jonathan A Meulbroek, Michael R Green, William N Pappano
{"title":"Inhibition of MALT1 and BCL2 Induces Synergistic Antitumor Activity in Models of B-Cell Lymphoma.","authors":"Joshua P Plotnik, Adam E Richardson, Haopeng Yang, Estela Rojas, Velitchka Bontcheva, Colleen Dowell, Sydney Parsons, Ashley Wilson, Vida Ravanmehr, Christine Will, Paul Jung, Haizhong Zhu, Sarathy Karunan Partha, Sanjay C Panchal, Raghuveer Singh Mali, Frederick J Kohlhapp, Ryan A McClure, Cyril Y Ramathal, Mariam D George, Manisha Jhala, Nathaniel L Elsen, Wei Qiu, Russell A Judge, Chin Pan, Anthony Mastracchio, Jared Henderson, Jonathan A Meulbroek, Michael R Green, William N Pappano","doi":"10.1158/1535-7163.MCT-23-0518","DOIUrl":"10.1158/1535-7163.MCT-23-0518","url":null,"abstract":"<p><p>The activated B cell (ABC) subset of diffuse large B-cell lymphoma (DLBCL) is characterized by chronic B-cell receptor signaling and associated with poor outcomes when treated with standard therapy. In ABC-DLBCL, MALT1 is a core enzyme that is constitutively activated by stimulation of the B-cell receptor or gain-of-function mutations in upstream components of the signaling pathway, making it an attractive therapeutic target. We discovered a novel small-molecule inhibitor, ABBV-MALT1, that potently shuts down B-cell signaling selectively in ABC-DLBCL preclinical models leading to potent cell growth and xenograft inhibition. We also identified a rational combination partner for ABBV-MALT1 in the BCL2 inhibitor, venetoclax, which when combined significantly synergizes to elicit deep and durable responses in preclinical models. This work highlights the potential of ABBV-MALT1 monotherapy and combination with venetoclax as effective treatment options for patients with ABC-DLBCL.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"949-960"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11217731/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140175644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Takuma Uo, Kayode K Ojo, Cynthia C T Sprenger, Kathryn S Epilepsia, B Gayani K Perera, Mamatha Damodarasamy, Shihua Sun, Soojin Kim, Hannah H Hogan, Matthew A Hulverson, Ryan Choi, Grant R Whitman, Lynn K Barrett, Samantha A Michaels, Linda H Xu, Vicky L Sun, Samuel L M Arnold, Haley J Pang, Matthew M Nguyen, Anna-Lena B G Vigil, Varun Kamat, Lucas B Sullivan, Ian R Sweet, Ram Vidadala, Dustin J Maly, Wesley C Van Voorhis, Stephen R Plymate
{"title":"A Compound That Inhibits Glycolysis in Prostate Cancer Controls Growth of Advanced Prostate Cancer.","authors":"Takuma Uo, Kayode K Ojo, Cynthia C T Sprenger, Kathryn S Epilepsia, B Gayani K Perera, Mamatha Damodarasamy, Shihua Sun, Soojin Kim, Hannah H Hogan, Matthew A Hulverson, Ryan Choi, Grant R Whitman, Lynn K Barrett, Samantha A Michaels, Linda H Xu, Vicky L Sun, Samuel L M Arnold, Haley J Pang, Matthew M Nguyen, Anna-Lena B G Vigil, Varun Kamat, Lucas B Sullivan, Ian R Sweet, Ram Vidadala, Dustin J Maly, Wesley C Van Voorhis, Stephen R Plymate","doi":"10.1158/1535-7163.MCT-23-0540","DOIUrl":"10.1158/1535-7163.MCT-23-0540","url":null,"abstract":"<p><p>Metastatic castration-resistant prostate cancer remains incurable regardless of recent therapeutic advances. Prostate cancer tumors display highly glycolytic phenotypes as the cancer progresses. Nonspecific inhibitors of glycolysis have not been utilized successfully for chemotherapy, because of their penchant to cause systemic toxicity. This study reports the preclinical activity, safety, and pharmacokinetics of a novel small-molecule preclinical candidate, BKIDC-1553, with antiglycolytic activity. We tested a large battery of prostate cancer cell lines for inhibition of cell proliferation, in vitro. Cell-cycle, metabolic, and enzymatic assays were used to demonstrate their mechanism of action. A human patient-derived xenograft model implanted in mice and a human organoid were studied for sensitivity to our BKIDC preclinical candidate. A battery of pharmacokinetic experiments, absorption, distribution, metabolism, and excretion experiments, and in vitro and in vivo toxicology experiments were carried out to assess readiness for clinical trials. We demonstrate a new class of small-molecule inhibitors where antiglycolytic activity in prostate cancer cell lines is mediated through inhibition of hexokinase 2. These compounds display selective growth inhibition across multiple prostate cancer models. We describe a lead BKIDC-1553 that demonstrates promising activity in a preclinical xenograft model of advanced prostate cancer, equivalent to that of enzalutamide. BKIDC-1553 demonstrates safety and pharmacologic properties consistent with a compound that can be taken into human studies with expectations of a good safety margin and predicted dosing for efficacy. This work supports testing BKIDC-1553 and its derivatives in clinical trials for patients with advanced prostate cancer.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"973-994"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11219269/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140175643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The CDK4/6 Inhibitor Palbociclib Synergizes with ATRA to Induce Differentiation in AML.","authors":"Linhui Hu, Qian Li, Jiyu Wang, Huiping Wang, Xiyang Ren, Keke Huang, Yangyang Wang, Xue Liang, Lianfang Pu, Shudao Xiong, Zhimin Zhai","doi":"10.1158/1535-7163.MCT-23-0528","DOIUrl":"10.1158/1535-7163.MCT-23-0528","url":null,"abstract":"<p><p>Differentiation therapy based on ATRA almost cured acute promyelocytic leukemia (APL). However, it is disappointing that ATRA is not effective against other acute myeloid leukemia (AML) subtypes. Developing new and effective anti-AML therapies that promote leukemia differentiation is necessary. The CDK4/6-cyclin D pathway is a key initiator of the G1-S phase transition, which determines cell fate. Herein, we investigated whether the CDK4/6 inhibitor palbociclib would synergize with ATRA to promote leukemia differentiation in vitro and in vivo. Our findings revealed that CDK4/6-cyclin D pathway genes were aberrantly expressed in AML, and we observed that palbociclib sensitized AML cells to ATRA-induced morphologic, biochemical, and functional changes indicative of myeloid differentiation. The combination of palbociclib and ATRA attenuated AML cell expansion in vivo. These enhanced differentiation effects may be associated with the regulation of transcription factors, including RARα, E2F1, and STAT1. Overall, our findings demonstrate that CDK4/6 inhibition sensitizes AML cells to ATRA and could guide the development of novel therapeutic strategies for patients with AML.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"961-972"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140175645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Michael S Nakazawa, Ian M Silverman, Victoria Rimkunas, Artur Veloso, Dominik Glodzik, Adrienne Johnson, Toshiro K Ohsumi, Shreyaskumar R Patel, Anthony P Conley, Christina L Roland, Pamela T Soliman, Hannah C Beird, Chia-Chin Wu, Davis R Ingram, Rossana Lazcano, Dawon Song, Khalida M Wani, Alexander J Lazar, Timothy A Yap, Wei-Lien Wang, J Andrew Livingston
{"title":"Loss of the DNA Repair Gene RNase H2 Identifies a Unique Subset of DDR-Deficient Leiomyosarcomas.","authors":"Michael S Nakazawa, Ian M Silverman, Victoria Rimkunas, Artur Veloso, Dominik Glodzik, Adrienne Johnson, Toshiro K Ohsumi, Shreyaskumar R Patel, Anthony P Conley, Christina L Roland, Pamela T Soliman, Hannah C Beird, Chia-Chin Wu, Davis R Ingram, Rossana Lazcano, Dawon Song, Khalida M Wani, Alexander J Lazar, Timothy A Yap, Wei-Lien Wang, J Andrew Livingston","doi":"10.1158/1535-7163.MCT-23-0761","DOIUrl":"10.1158/1535-7163.MCT-23-0761","url":null,"abstract":"<p><p>Targeting the DNA damage response (DDR) pathway is an emerging therapeutic approach for leiomyosarcoma (LMS), and loss of RNase H2, a DDR pathway member, is a potentially actionable alteration for DDR-targeted treatments. Therefore, we designed a protein- and genomic-based RNase H2 screening assay to determine its prevalence and prognostic significance. Using a selective RNase H2 antibody on a pan-tumor microarray (TMA), RNase H2 loss was more common in LMS (11.5%, 9/78) than across all tumors (3.8%, 32/843). In a separate LMS cohort, RNase H2 deficiency was confirmed in uterine LMS (U-LMS, 21%, 23/108) and soft-tissue LMS (ST-LMS; 30%, 39/102). In the TCGA database, RNASEH2B homozygous deletions (HomDels) were found in 6% (5/80) of LMS cases, with a higher proportion in U-LMS (15%; 4/27) compared with ST-LMS (2%; 1/53). Using the SNiPDx targeted-NGS sequencing assay to detect biallelic loss of function in select DDR-related genes, we found RNASEH2B HomDels in 54% (19/35) of U-LMS cases with RNase H2 loss by IHC, and 7% (3/43) HomDels in RNase H2 intact cases. No RNASEH2B HomDels were detected in ST-LMS. In U-LMS patient cohort (n = 109), no significant overall survival difference was seen in patients with RNase H2 loss versus intact, or RNASEH2B HomDel (n = 12) versus Non-HomDel (n = 37). The overall diagnostic accuracy, sensitivity, and specificity of RNase H2 IHC for detecting RNA-SEH2B HomDels in U-LMS was 76%, 93%, and 71%, respectively, and it is being developed for future predictive biomarker driven clinical trials targeting DDR in U-LMS.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1057-1065"},"PeriodicalIF":5.3,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11321279/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140336248","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}