{"title":"Inhibition of PSF activity overcomes resistance to treatment in cancers harboring mutant p53.","authors":"Ken-Ichi Takayama, Tomohiro Sato, Teruki Honma, Minoru Yoshida, Satoshi Inoue","doi":"10.1158/1535-7163.MCT-24-0418","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0418","url":null,"abstract":"<p><p>Mutations in the TP53 tumor suppressor genes are prevalent in aggressive cancers. Pharmacological reactivation of dysfunctional p53 due to mutations is a promising strategy for treating such cancers. Recently, a multifunctional proline- and glutamine-rich protein, PTB-associated splicing factor (PSF), was identified as a key driver of aggressive cancers. PSF promotes the expression of numerous oncogenes by modulating epigenetic and splicing mechanisms. We previously screened a small-molecule library and discovered compound No.10-3 as a potent PSF inhibitor. Here, we report the discovery of a No.10-3 analog, C-30, as a potent PSF inhibitor. Compared to No.10-3, C-30 treatment specifically suppressed the growth and induced apoptosis of mutant p53-bearing and therapy-resistant cancer cells. Interestingly, C-30 activated a set of p53-regulated genes in therapy-resistant cancer cells. A comprehensive analysis of PSF and p53 binding regions demonstrated a higher level of PSF-binding potential in mutant p53-expressing cancer cells around genomic regions identified as p53-binding peaks in p53-wild type cancer cells. Treatment of mutant p53-expressing cancer cells with C-30 decreases PSF binding around these sites, leading to activated histone acetylation. We further demonstrated that C-30 impaired tumor growth and increased the expression of p53-target genes in vivo. These results suggested that C-30 produces tumor-suppressive effects similar to the functional reactivation of p53, providing a rationale for the inhibition of PSF activity as a promising therapy against treatment-resistant cancer.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142770321","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}
Xinyi Yang, Yuanyuan Liu, Peng Wang, Min Li, Tong Xiang, Songzuo Xie, Minxing Li, Yan Wang, Desheng Weng, Jingjing Zhao
{"title":"Targeting PDHK1 by DCA to Restore NK Cell Function in Hepatocellular Carcinoma.","authors":"Xinyi Yang, Yuanyuan Liu, Peng Wang, Min Li, Tong Xiang, Songzuo Xie, Minxing Li, Yan Wang, Desheng Weng, Jingjing Zhao","doi":"10.1158/1535-7163.MCT-24-0222","DOIUrl":"10.1158/1535-7163.MCT-24-0222","url":null,"abstract":"<p><p>Pyruvate dehydrogenase complex is a crucial enzyme involved in the oxidation of glucose. It is regulated by pyruvate dehydrogenase kinase (PDHK) and pyruvate dehydrogenase phosphatase. Studies have demonstrated that PDHK1, a key enzyme in glucose metabolism, behaves like oncogenes. It is highly expressed in tumors and is associated with poor patient prognosis. However, there is limited research on how PDHK1 affects immune cell function. We have established a model of NK cell exhaustion to investigate the impact of dichloroacetate (DCA) on NK cell function. The production of granzyme B, IFNγ, TNFα, and CD107a by NK cells was explored by flow cytometry. The real-time live-cell imaging system was used to monitor the ability of NK cells against tumor cells. The Seahorse analyzer was utilized to measure the oxygen consumption rate and extracellular acidification rate of NK cells. A mouse model was used to investigate the potential of combining DCA with adjuvant NK cell infusion. Our study demonstrated that the hepatocellular carcinoma microenvironment mediated NK cellular exhaustion and high expression of PDHK1 and reduced cytokine secretion. We discovered that the PDHK1 inhibitor DCA enhances the activity and function of exhausted NK cells infiltrating the tumor microenvironment. Furthermore, in a s.c. hepatocellular carcinoma mouse model, DCA combined with NK cell treatment resulted in retarding cancer progression. This study indicates the potential of DCA in rescuing NK cell exhaustion and eliciting antitumor immunity.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1731-1742"},"PeriodicalIF":5.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142004820","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}
Robinson Triboulet, Khikmet Sadykov, Darren M Harvey, David M Wilson, Michael J Steinbaugh, Christopher B Mayo, Dillon Hawley, Andrew Madanjian, Corey Fyfe, Christina Bracken, Izarys Rivera-Rivera, Anna Ericsson, Andrew R Snyder, Sarah K Knutson, Ross L Stein, Veronica Gibaja, Shomir Ghosh, Robert M Campbell
{"title":"Targeting the Synthetic Lethal Relationship between FOCAD and TUT7 Represents a Potential Therapeutic Opportunity for TUT4/7 Small-Molecule Inhibitors in Cancer.","authors":"Robinson Triboulet, Khikmet Sadykov, Darren M Harvey, David M Wilson, Michael J Steinbaugh, Christopher B Mayo, Dillon Hawley, Andrew Madanjian, Corey Fyfe, Christina Bracken, Izarys Rivera-Rivera, Anna Ericsson, Andrew R Snyder, Sarah K Knutson, Ross L Stein, Veronica Gibaja, Shomir Ghosh, Robert M Campbell","doi":"10.1158/1535-7163.MCT-24-0176","DOIUrl":"10.1158/1535-7163.MCT-24-0176","url":null,"abstract":"<p><p>Targeting synthetic lethal interactions among genes has emerged as a promising strategy for cancer therapy. This study explores the intricate interplay among terminal uridylyltransferase 4 (TUT4) and terminal uridylyltransferase 7 (TUT7), the 3'-5' exoribonuclease DIS3L2, and the superkiller (SKI) complex-interacting factor focadhesin (FOCAD) in the context of cancer vulnerability. Using CRISPR and public functional genomics data, we show impairment of cell proliferation upon knockout of TUT7 or DIS3L2, but not TUT4, on cancer cells with FOCAD loss. Moreover, we report the characterization of the first potent and selective TUT4/7 inhibitors that substantially reduce uridylation and demonstrate in vitro and in vivo antiproliferative activity specifically in FOCAD-deleted cancer. FOCAD deficiency posttranscriptionally disrupts the stability of the SKI complex, whose role is to safeguard cells against aberrant RNA. Reintroduction of FOCAD restores the SKI complex and makes these cells less sensitive to TUT4/7 inhibitors, indicating that TUT7 dependency is driven by FOCAD loss. We propose a model in which, in the absence of FOCAD, TUT7 and DIS3L2 function as a salvage mechanism that degrades aberrant RNA, and genetic or pharmacologic inhibition of this pathway leads to cell death. Our findings underscore the significance of FOCAD loss as a genetic driver of TUT7 vulnerability and provide insights into the potential utility of TUT4/7 inhibitors for cancer treatment.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1779-1788"},"PeriodicalIF":5.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142133245","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 Giarrizzo, Joseph F LaComb, Hetvi R Patel, Rohan G Reddy, John D Haley, Lee M Graves, Edwin J Iwanowicz, Agnieszka B Bialkowska
{"title":"TR-107, an Agonist of Caseinolytic Peptidase Proteolytic Subunit, Disrupts Mitochondrial Metabolism and Inhibits the Growth of Human Colorectal Cancer Cells.","authors":"Michael Giarrizzo, Joseph F LaComb, Hetvi R Patel, Rohan G Reddy, John D Haley, Lee M Graves, Edwin J Iwanowicz, Agnieszka B Bialkowska","doi":"10.1158/1535-7163.MCT-24-0170","DOIUrl":"10.1158/1535-7163.MCT-24-0170","url":null,"abstract":"<p><p>Oxidative phosphorylation is an essential metabolic process for cancer proliferation and therapy resistance. The ClpXP complex maintains mitochondrial proteostasis by degrading misfolded proteins. Madera Therapeutics has developed a class of highly potent and selective small-molecule activators (TR compounds) of the ClpXP component caseinolytic peptidase proteolytic subunit (ClpP). This approach to cancer therapy eliminates substrate recognition and activates nonspecific protease function within mitochondria, which has shown encouraging preclinical efficacy in multiple malignancies. The class-leading compound TR-107 has demonstrated significantly improved potency in ClpP affinity and activation and enhanced pharmacokinetic properties over the multitargeting clinical agent ONC201. In this study, we investigate the in vitro efficacy of TR-107 against human colorectal cancer cells. TR-107 inhibited colorectal cancer cell proliferation in a dose- and time-dependent manner and induced cell cycle arrest at low nanomolar concentrations. Mechanistically, TR-107 downregulated the expression of proteins involved in the mitochondrial unfolded protein response and mitochondrial DNA transcription and translation. TR-107 attenuated oxygen consumption rate and glycolytic compensation, confirming inactivation of oxidative phosphorylation and a reduction in total cellular respiration. Multiomics analysis of treated cells indicated a downregulation of respiratory chain complex subunits and an upregulation of mitophagy and ferroptosis pathways. Further evaluation of ferroptosis revealed a depletion of antioxidant and iron toxicity defenses that could potentiate sensitivity to combinatory chemotherapeutics. Together, this study provides evidence and insight into the subcellular mechanisms employed by colorectal cancer cells in response to potent ClpP agonism. Our findings demonstrate a productive approach to disrupting mitochondrial metabolism, supporting the translational potential of TR-107.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1761-1778"},"PeriodicalIF":5.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11614700/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142133246","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":"Advanced Human Papillomavirus-Negative Head and Neck Squamous Cell Carcinoma: Unmet Need and Emerging Therapies.","authors":"Robin Park, Christine H Chung","doi":"10.1158/1535-7163.MCT-24-0281","DOIUrl":"10.1158/1535-7163.MCT-24-0281","url":null,"abstract":"<p><p>Despite notable progress in the treatment of advanced head and neck squamous cell carcinoma (HNSCC), survival remains poor in patients with recurrent and/or metastatic (R/M) human papillomavirus (HPV)-negative HNSCC. Worse outcomes in patients who are HPV-negative may be partly related to loss of cell-cycle regulators and tumor suppressors as well as a noninflamed and hypoxic tumor microenvironment, both of which contribute to treatment resistance and disease progression. Anti-programmed cell death protein 1-based regimens as current standard-of-care treatment for R/M HNSCC are associated with durable responses in a limited number of patients. The anti-EGFR mAb, cetuximab, has antitumor activity in this treatment setting, but responses are short-lived and inevitably curtailed due to treatment resistance. Crosstalk between the EGFR and hepatocyte growth factor-dependent mesenchymal-epithelial transition (c-MET) receptor tyrosine kinase pathway is a known mechanism of resistance to cetuximab. Dual targeting of EGFR and c-MET pathways may overcome resistance to cetuximab in patients with HPV-negative HNSCC. Here, we review clinical data of treatments evaluated in patients with R/M HPV-negative HNSCC and highlight the potential role of combining hepatocyte growth factor/c-MET and EGFR pathway inhibitors to overcome cetuximab resistance in this population.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":"1717-1730"},"PeriodicalIF":5.3,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11612620/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142291432","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}
Geertruid J Brink, Nizar Hami, Sander Mertens, Hans W Nijman, Luc Rcw van Lonkhuijzen, Eva Maria Roes, Christine A R Lok, Cornelis D de Kroon, Jurgen Mj Piek, Ward Hofhuis, Hugo J G Snippert, Jolijn Willemijntje Groeneweg, Petronella O Witteveen, Ronald P Zweemer
{"title":"Response to systemic therapies in patient-derived cell lines from primary and recurrent adult granulosa cell tumors.","authors":"Geertruid J Brink, Nizar Hami, Sander Mertens, Hans W Nijman, Luc Rcw van Lonkhuijzen, Eva Maria Roes, Christine A R Lok, Cornelis D de Kroon, Jurgen Mj Piek, Ward Hofhuis, Hugo J G Snippert, Jolijn Willemijntje Groeneweg, Petronella O Witteveen, Ronald P Zweemer","doi":"10.1158/1535-7163.MCT-24-0223","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0223","url":null,"abstract":"<p><p>In patients with the rare adult-type granulosa cell tumors (aGCT), surgery is the primary treatment for both primary and recurrent disease. In cases of inoperable disease, systematic therapy is administered, but variable response rates and drug resistance complicate predicting the most effective therapy. Drug screen testing on patient-derived cell lines may offer a solution. In a national prospective study on aGCT, fresh tissue was cultured into 2D cell lines, testing 27 clinically and experimental drugs. Dose-response curves and synergy were calculated using GraphPad Prism and Compusyn software. We established 34 patient-derived cell lines from tissue of 20 adult granulosa cell tumor patients. Of these, seven patients had a primary diagnosis of adult granulosa cell tumor and 13 patients had recurrent disease. In eight patients multiple tumor locations were cultured. On each cell line 10 monotherapies and 17 combinations of drugs were tested. Carboplatin/gemcitabine showed efficacy and synergy in almost all patient-derived cell lines. Synergy could not be detected in the regular carboplatin/paclitaxel and carboplatin/etoposide combinations. Experimental combinations alpelisib/fulvestrant and alpelisib/gemcitabine showed efficacy of more than 75%. Drug screens on patient-derived tumor cell lines reflects the reality of the variable response of systemic therapy in aGCT patients. In future research, this technique may be used to personalize the systemic treatment of aGCT patients in a clinical study. The good response to carboplatin/gemcitabine in our patient-derived cell lines can then be confirmed in a clinical setting.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142730738","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}
Xuemei Xie, Maroua Manai, Dileep R Rampa, Jon A Fuson, Elizabeth S Nakasone, Troy Pearson, Bharat S Kuntal, Debu Tripathy, Naoto T Ueno, Jangsoon Lee
{"title":"Targeting CDK7 enhances the antitumor efficacy of enzalutamide in androgen receptor-positive triple-negative breast cancer by inhibiting c-MYC-mediated tumorigenesis.","authors":"Xuemei Xie, Maroua Manai, Dileep R Rampa, Jon A Fuson, Elizabeth S Nakasone, Troy Pearson, Bharat S Kuntal, Debu Tripathy, Naoto T Ueno, Jangsoon Lee","doi":"10.1158/1535-7163.MCT-23-0386","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-23-0386","url":null,"abstract":"<p><p>Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer. Among TNBC subtypes, the luminal androgen receptor (LAR) subtype expresses high levels of androgen receptor (AR) and generally responds poorly to neoadjuvant chemotherapy. AR has been reported as a promising therapeutic target for the LAR TNBC subtype. Here, we evaluated the preclinical antitumor efficacy of enzalutamide, an AR inhibitor, in TNBC. Enzalutamide had moderate anti-proliferation activity against AR-positive (AR+) TNBC cells (IC50 > 15 µM). To enhance its antitumor efficacy, we performed high-throughput kinome siRNA screening and identified the cell cycle pathway as a potential target. Inhibition of cell cycle progression using the CDK7 inhibitor KRLS-017 showed a synergistic anti-proliferation effect with enzalutamide in AR+ LAR MDA-MB-453 and SUM185 TNBC cells. Downstream target analysis revealed that enzalutamide and KRLS-017 combination dramatically reduced c-MYC expression at both mRNA and protein levels. c-MYC knockdown significantly suppressed growth of MDA-MB-453 and SUM185 cells to a degree comparable to that of enzalutamide and KRLS-017 combination treatment, whereas c-MYC overexpression reversed the synergistic effect. An enhancement in inhibition of tumor growth and suppression of c-MYC expression was further confirmed when enzalutamide combined with KRLS-017 in an MDA-MB-453 mouse model. Our study suggests that KRLS-017 enhances the antitumor efficacy of enzalutamide by inhibiting c-MYC-mediated tumorigenesis and presents a potential new approach for treating AR+ LAR TNBC.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142716593","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}
Aaron E Fan, Hussein Sultan, Takumi Kumai, Valentyna I Fesenkova, Juan Wu, John D Klement, Joshua D Bernstock, Gregory K Friedman, Esteban Celis
{"title":"STAT5 activation enhances adoptive therapy combined with peptide vaccination by preventing PD-1 inhibition.","authors":"Aaron E Fan, Hussein Sultan, Takumi Kumai, Valentyna I Fesenkova, Juan Wu, John D Klement, Joshua D Bernstock, Gregory K Friedman, Esteban Celis","doi":"10.1158/1535-7163.MCT-24-0505","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0505","url":null,"abstract":"<p><p>Adoptive cell therapy (ACT) using retrovirally transduced T cells represents a promising strategy for enhancing antitumor responses. When used with TriVax, a peptide vaccination strategy, this approach synergistically expands antigen-specific cell populations. STAT5 plays a vital role as a transcription factor in regulating T cell proliferation and their differentiation into effector and memory T cells. We aimed to explore the combination therapy using CD8 T cells engineered to express constitutively active STAT5 (CA-STAT5) with vaccines. CD8 T cells were transduced with a retrovirus (RV) encoding the mouse gp100 T cell receptor (TCR). In certain treatment groups, cells were also co-transduced with RV encoding CA-STAT5. We assessed transduction efficiency and functional activity through flow cytometry and various functional assays. B16F10 tumor-bearing mice were treated with ACT using RV-transduced CD8 T cells and subsequently vaccinated with TriVax. We demonstrate that TriVax selectively enhanced the expansion of ACT cell populations bearing gp100-specific TCRs. T cells engineered to express CA-STAT5 showed not only increased expansion and polyfunctionality but also reduced PD-1 expression, leading to decreased cellular exhaustion. In a B16F10 melanoma mouse model, our approach yielded a potent antitumor effect, with CA-STAT5 further amplifying this response. We found that CA-STAT5 improved antitumor activities, in part, by attenuating the PD-1/PD-L1 inhibitory pathway. These findings indicate that TCR-transduced CD8 T cells can undergo antigen-dependent expansion when exposed to TriVax. Additionally, the expression of CA-STAT5 enhances T cell proliferation and persistence, partly by promoting resistance to PD-1/PD-L1-mediated inhibition in antitumor T cells.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142709746","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":"A novel designed anti-PD-L1/OX40 bispecific antibody augments both peripheral and tumor-associated immune responses for boosting anti-tumor immunity.","authors":"Baocun Li, Shiyong Gong, Nianying Zhang, Beilei Shi, Zhou Lv, Yu Zhang, Naren Gaowa, Liqin Dong, Danqing Wu, Jianfu Wu, Fan Liu, Rui Zhang, Ramin Behzadigohar, Vinod Ganju, Chengbin Wu, Xuan Wu","doi":"10.1158/1535-7163.MCT-24-0330","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0330","url":null,"abstract":"<p><p>Bispecific antibodies (BsAbs) combining simultaneous PD-L1 blockade and conditional co-stimulatory receptor activation have been developed to improve immune checkpoint therapy response. However, several PD-L1-based BsAbs have encountered clinical challenges, including insufficient activity or unexpected toxicity. In this study, we propose OX40 as a more suitable target partner for PD-L1-based BsAb design compared to ongoing clinical partners (CD27 and 4-1BB). We present a novel Fc-silenced tetravalent PD-L1/OX40 BsAb (EMB-09), which efficiently blocks PD-1/PD-L1 interactions and induces PD-L1-dependent OX40 activation, leading to enhanced T cell activation. EMB-09 demonstrated improved anti-tumor activity compared to the anti-PD-L1 monoclonal antibody. Significantly, EMB-09 activated effector memory T cells in peripheral immune system, promoted the influx of stem-like CD8+ T cells into the tumor site, resulting in a more active phenotype of CD8+ tumor-infiltrating lymphocytes. In an ongoing first-in-human study in patients with advanced refractory solid tumors (NCT05263180), EMB-09 demonstrated a consistent pharmacodynamic response and early efficacy signals.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142687683","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}
Eleni Papacharisi, Alexandra Braun, Marija Vranic, Andreas M Pahl, Torsten Hechler
{"title":"Novel Amanitin-based Antibody Drug Conjugates (ATAC®) targeting TROP2 for the treatment of Pancreatic Cancer.","authors":"Eleni Papacharisi, Alexandra Braun, Marija Vranic, Andreas M Pahl, Torsten Hechler","doi":"10.1158/1535-7163.MCT-24-0266","DOIUrl":"https://doi.org/10.1158/1535-7163.MCT-24-0266","url":null,"abstract":"<p><p>Trophoblast cell surface antigen 2 (TROP2) exhibits aberrant expression in pancreatic cancer, correlating with metastasis, advanced tumor stage and poor prognosis of pancreatic ductal adenocarcinoma (PDAC) patients. TROP2 has been recognized as a promising therapeutic target for antibody drug conjugates (ADCs), as evidenced by the approval of the anti-TROP2 ADC Trodelvy® for the treatment of triple negative breast cancer. In this study we report the generation of novel second-generation amanitin based ADCs (ATAC®s) targeting TROP2, comprising the humanized RS7 antibody of Trodelvy® (hRS7) and the highly potent payload amanitin. The specific in vitro binding, efficient antigen internalization, and high cytotoxicity of hRS7 ATAC®s with half maximal effective concentration (EC50) values in the picomolar range in TROP2-expressing cells constituted the foundation for preclinical in vivo evaluation. The hRS7 ATAC®s demonstrated a significant reduction in tumor growth in vivo in subcutaneous xenograft mouse models of pancreatic cancer and triple negative breast cancer at well-tolerated doses. The antitumor efficacy correlated with the level of TROP2 expression on the tumors and the in vivo tumor uptake of the ATAC®s. The long half-life of 9.7-10.7 days of hRS7 ATAC®s without premature payload release in serum supported a high therapeutic index. Notably, the efficacy of the hRS7 ATAC®s was superior to that of Trodelvy® with complete tumor eradication in both, refractory pancreatic and triple negative breast cancer xenograft models. In summary, hRS7 ATAC®s represent a highly effective and well-tolerated targeted therapy, and our data support their development for pancreatic cancer and other TROP2-expressing tumors.</p>","PeriodicalId":18791,"journal":{"name":"Molecular Cancer Therapeutics","volume":" ","pages":""},"PeriodicalIF":5.3,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142676379","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}