Project description:Cdk4/6 inhibitors have shown to increase overall survival in hormone-positive breast tumors, but whether other solid tumors could respond to these inhibitors has not yet defined. Here we show that Palbociclib (a Cdk4/6 specific inhibitor in clinic use) + cisplatin (CDDP, a chemotherapeutic agent most active in locally or advanced bladder cancer patients) treatment exerts antiproliferative effects in vivo using a bladder cancer mouse model.
Project description:Cdk4/6 inhibitors have shown to increase overall survival in hormone-positive breast tumors, but whether other solid tumors could respond to these inhibitors has not yet defined. Here we show that Palbociclib (a Cdk4/6 specific inhibitor in clinic use) treatment exerts antiproliferative effects in vivo using a bladder cancer cell lines.
Project description:KRAS mutant pancreatic tumors have poor prognosis and few therapeutic options. Here, Frank et al. show that the combination of RMC4550 (SHP2 inhibitor) and LY3214996 (ERK inhibitor) effectively impairs tumor growth and induces tumor regression in multiplein vivo models of PDAC .
Project description:KRAS mutant pancreatic tumors have poor prognosis and few therapeutic options. Here, Frank et al. show that the combination of RMC4550 (SHP2 inhibitor) and LY3214996 (ERK inhibitor) effectively impairs tumor growth and induces tumor regression in multiplein vivo models of PDAC .
Project description:Numerous case studies have reported spontaneous regression of metastases following tumor excision, but underlying mechanisms are elusive. Here we present a model of metastases regression and latency elicited by the removal of a primary tumor, and identify underlying mechanisms. Human breast cancer cells, expressing highly sensitive luciferase, were implanted into the mammary fat-pad of mice, and the progression of early stage micrometastases, was monitored. Upon establishment of micrometastases, the primary tumor was excised, inducing a robust regression of metastatic signal, resulting in latent foci. In vivo supplementation of tumor secretome immediately upon tumor excision diminished this regression, implicating primary tumor secreted factors in promotion of metastatic growth. In vitro, cancer cell conditioned medium reduced apoptosis and enhanced adhesion of non-confluent cancer cells, and induced angiogenesis in endothelial cells. Cytokine array and proteomic analysis of cancer cells secretome identified 359 extracellular secreted factors, with significant enrichment of angiogenic factors, growth factors activity, focal adhesion, apoptosis, and metalloprotease processes. In vivo blockade of four key potential mediators of these processes, IL-8, PDGFaa, Serpin E1 (PAI-1), and MIF, arrested development of micrometastases. Moreover, high protein levels of these four factors were correlated with poor patient outcome. These results demonstrate regression and latency of metastases following tumor excision and a crucial role for primary tumor secretome in promoting early metastatic stages, suggesting novel mechanisms to control minimal residual disease.
Project description:Resistance to aromatase inhibitor (AI) treatment and combined CDK4/6 inhibitor (CDK4/6i) and endocrine therapy (ET) are crucial clinical challenges in treating estrogen receptor-positive (ER+) breast cancer. Understanding the resistance mechanisms and identifying reliable predictive biomarkers and novel treatment combinations to overcome resistance are urgently needed. Herein, we show that upregulation of CDK6, p-CDK2, and/or cyclin E1 is associated with adaptation and resistance to AI-monotherapy and combined CDK4/6i and ET in ER+ advanced breast cancer. Importantly, co-targeting CDK2 and CDK4/6 with ET synergistically impairs cellular growth, induces cell cycle arrest and apoptosis, and delays progression in AI-resistant and combined CDK4/6i and fulvestrant-resistant cell models and in an AI-resistant autocrine breast tumor in a postmenopausal xenograft model. Analysis of CDK6, p-CDK2, and/or cyclin E1 expression as a combined biomarker in metastatic lesions of ER+ advanced breast cancer patients treated with AI-monotherapy or combined CDK4/6i and ET revealed a correlation between high biomarker expression and shorter progression-free survival (PFS), and the biomarker combination was an independent prognostic factor in both patients cohorts. Our study supports the clinical development of therapeutic strategies co-targeting ER, CDK4/6 and CDK2 following progression on AI-monotherapy or combined CDK4/6i and ET to improve survival of patients exhibiting high tumor levels of CDK6, p-CDK2, and/or cyclin E1.
Project description:We investigated the mechanisms of acquired resistance to the CDK4 selective inhibitor atirmociclib in HR+ HER2- breast cancer in vivo, using the ZR751 xenograft model. Atirmociclib resistant tumors appeared after long-term (>50 day) treatment with atirmociclib. Tumor material was isolated from resistant (85-day treatment) as well as sensitive/vehicle treated (3-day) tumor bearing mice and subjected to RNA-seq analysis.
Project description:Background: Despite current therapeutic treatments including surgery, chemotherapy, radiotherapy and recently immunotherapy, the mortality rate of lung cancer stays high. Regarding lung cancer, epigenetic modifications altering cell cycle, angiogenesis and programmed cancer cell death are therapeutic targets to combine with immunotherapy to improve treatment success. In a recent study, we uncovered a dual function of a molecule called QAPHA ((E)-3-(5-((2-cyanoquinolin-4-yl)(methyl)amino)-2-methoxyphenyl)-N-hydroxyacrylamide) as both a tubulin polymerization and HDAC inhibitors. Here, we investigate the impact of this novel dual inhibitor on the lung cancer immune response. Methods: To elucidate the mechanism of action of QAPHA, we conducted a chemical proteomics analysis. Using an in vivo mouse model of lung cancer (TC-1 tumor cells), we assessed the effects of QAPHA on tumor regression. Tumor infiltrating immune cells were characterize by flow cytometry. Results In this study, we first show that QAPHA can inhibit HDAC6, leading to upregulation of HSP90, cytochrome C and caspases, found by proteomic analysis. We also confirm that QAPHA induces immunogenic cell death (ICD) by upregulating HMGB1 in vitro and demonstrated its effectiveness as a vaccine in vivo. Remarkably, even at a low concentration (0.5mg/kg), QAPHA achieved complete tumor regression in approximately 60% of intratumorally treated mice, establishing a long-lasting anticancer immune response. Moreover, QAPHA treatment promoted infiltration of neutrophils in the treated mice, reflecting inflammatory cell death promoted. Very interestingly, we show that QAPHA is also able to upregulate MHC-II expression on TC-1 tumor cells in vitro and in vivo. This process participates to the recruitment of CD4+ NKG2D+ CRTAM+ Perforin+ T cells in tumor infiltrate, defined as cytotoxic CD4+ T cells (CD4+ CTL). Finally, we show that tumor regression is strongly correlated to MHC-II expression level on tumor cell and CD4+ CTL infiltrate. Conclusion Collectively, our findings shed light on the discovery of a new multi-target inhibitor able to induce ICD and MHC-II upregulation in TC-1 tumor cell. These two processes participate to enhance a specific CD4+ cytotoxic T cell-mediated anti-tumor response in vivo in our model of lung cancer. This breakthrough suggests the potential of QAPHA as a promising therapeutic agent for cancer treatment.
Project description:Metastatic bladder cancer is a malignant tumor with high metastatic potential. The etiology and molecular mechanism are still not fully understood. This study aimed to investigate the effect of PGC-1 α siRNA delivered by liposomal nanoparticles on bladder cancer cells, in order to reveal its mechanism in tumor cell reprogramming and energy metabolism regulation. Through transcriptome, proteome and metabolomics, we found that PGC-1 α was significantly upregulated in bladder cancer metastasis, and constructed a nanoparticle delivery system for efficient delivery of PGC-1 α siRNA. In vitro results showed that PGC-1 α silencing inhibited mitochondrial biogenesis and energy metabolism in bladder cancer cells, and interfered with the extranuclear transport of mRNA. Metabolomic analysis further confirmed the changes in cellular metabolism, especially the effects of glycolysis and tricarboxylic acid cycle pathways. The in vivo model further verified that si-pgc-1 α LNP could significantly reduce the number of lung metastases of metastatic bladder cancer, showing anti metastatic potential. These findings reveal the important role of PGC-1 α in the regulation of energy metabolism and metastasis of bladder cancer cells, and provide a new strategic direction for the treatment of metastatic bladder cancer.