Role of Peroxisome Proliferator Activated Receptor-Gamma in Bacillus Calmette-Guérin Bladder Cancer Therapy

Purpose: We evaluated the effects of combined PPARg agonist with bacillus Calmette-Guérin in bladder cancer growth in vitro and in vivo, focusing on the tissue remodeling mechanisms induced by bacillus Calmette-Guérin. Materials and Methods: PPARs are a superfamily of nuclear receptors that are transcription factors activated by ligands. Activation of PPARg, the subtype, causes proliferation inhibition or differentiation of tumor cells. Previously, we reported that the inhibition of murine bladder tumor growth induced by bacillus Calmette-Guérin, which is the standard treatment for patients with nonmuscle invasive, high grade bladder cancer, increased PPARg expression in vitro and in vivo. In vitro the cell growth inhibition induced by bacillus Calmette-Guérin was enhanced by the PPARg agonist 15-d-PGJ2, raising the possibility that PPARg activation may be a therapeutic modality for this disease. Results: In MB49 cells bacillus Calmette-Guérin and 15-d-PGJ2 induced PPARg expression, nuclear translocation and transcriptional activity. In vivo bacillus Calmette-Guérin reduced tumor size, an effect that was partially reversed when bacillus Calmette-Guérin was combined with the PPARg agonist rosiglitazone. The same result was found when we analyzed the effect of the PPARg antagonist BADGE (Fluka Chemical, Buchs, Switzerland) combined with bacillus Calmette- Guérin. Analysis of the activation of macrophages and fibroblasts demonstrated that rosiglitazone inhibited the tissue remodeling mechanisms induced by bacillus Calmette-Guérin. Conclusions: Results suggest that PPARg is involved in the antitumor action of bacillus Calmette-Guérin. However, exogenous PPARg agonists would not be a favorable therapeutic modality because they can inhibit the tissue remodeling needed for an overall satisfactory bacillus Calmette-Guérin response.Fil: Langle, Yanina Verónica. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Lodillinsky, Catalina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; ArgentinaFil: Belgorosky, Denise. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sandes, Eduardo Omar. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; ArgentinaFil: Eiján, Ana Maria. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología; Argentin

Ephrin-B1 Is a novel biomarker of bladder cancer aggressiveness. studies in murine models and in human samples

Bladder cancer (BC) is the ninth most common cancer worldwide, but molecular changes are still under study. During tumor progression, Epithelial cadherin (E-cadherin) expression is altered and β-catenin may be translocated to the nucleus, where it acts as co-transcription factor of tumor invasion associated genes. This investigation further characterizes E-cadherin and β-catenin associated changes in BC, by combining bioinformatics, an experimental murine cell model (MB49/MB49-I) and human BC samples. In in silico studies, a DisGeNET (gene-disease associations database) analysis identified CDH1 (E-cadherin gene) as one with highest score among 130 BC related-genes. COSMIC mutation analysis revealed CDH1 low mutations rates. Compared to MB49 control BC cells, MB49-I invasive cells showed decreased E-cadherin expression, E- to P-cadherin switch, higher β-catenin nuclear signal and lower cytoplasmic p-Ser33-β-catenin signal, higher Ephrin-B1 ligand and EphB2 receptor expression, higher Phospho-Stat3 and Urokinase-type Plasminogen Activator (UPA), and UPA receptor expression. MB49-I cells transfected with Ephrin-B1 siRNA showed lower migratory and invasive capacity than control cells (scramble siRNA). By immunohistochemistry, orthotopic MB49-I tumors had lower E-cadherin, increased nuclear β-catenin, lower pSer33-β-catenin cytoplasmic signal, and higher Ephrin-B1 expression than MB49 tumors. Similar changes were found in human BC tumors, and 83% of infiltrating tumors depicted a high Ephrin-B1 stain. An association between higher Ephrin-B1 expression and higher stage and tumor grade was found. No association was found between abnormal E-cadherin signal, Ephrin-B1 expression or clinical-pathological parameter. This study thoroughly analyzed E-cadherin and associated changes in BC, and reports Ephrin-B1 as a new marker of tumor aggressiveness.Fil: Mencucci, Maria Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Endocrinología Experimental y Aplicada. Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Endocrinología Experimental y Aplicada; ArgentinaFil: Lapyckyj, Lara. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Rosso, Marina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Besso, María José. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Belgorosky, Denise. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Isola, Mariana. Hospital Italiano; ArgentinaFil: Vanzulli, Silvia. Academia Nacional de Medicina de Buenos Aires; ArgentinaFil: Lodillinsky, Catalina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Eiján, Ana María. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Tejerizo, Juan Carlos. Hospital Italiano; ArgentinaFil: González, Matías Ignacio. Hospital Italiano; ArgentinaFil: Zubieta, María Ercilia. Hospital Italiano; ArgentinaFil: Vazquez, Monica Hebe. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentin

Nitric oxide synthase, arginase and cyclooxygenase are involved in muscarinic receptor activation in different murine mammary adenocarcinoma cell lines

Investigations on the influence of the parasympathetic nervous system via muscarinic signaling in tumor progression have produced contradictory evidence. We investigated the expression of muscarinic acetylcholine receptors (mAchR) and their intracellular transduction pathways, in two murine mammary adenocarcinoma cell lines, LM3 and LM2 in comparison with the normal murine mammary epithelial cell line: NMuMG. Saturation binding assays with the tritiated muscarinic antagonist quinuclidinyl benzilate ([3H]-QNB) indicate that LM3 cells express higher amounts of mAchR than LM2 cells. Muscarinic receptor activation with carbachol (CARB) enhanced basal production of citrulline to a greater extent in LM3 cells than in LM2 cells. The nitric oxide synthase (NOS) inhibitor, NGmono-methyl-L-arginine (L-NMMA), blunted this effect only in LM3 cells while in LM2 cells the action of CARB was blocked by N? hydroxy-L-arginine (L-OH-Arg), which is known to inhibit the arginase pathway. Atropine blocks the action of CARB in both cell lines. Additionally, mAchR activation stimulates prostaglandin E2 (PGE2) synthesis only in LM2 cells. NMuMG cells show detectable basal amounts of nitric oxide and PGE2, but they did not respond to CARB. Binding experiments confirm the absence of mAchR in these cells. The findings indicate that mAchR expression in tumor cells, and its control on arginine metabolism, via NOS/arginase, and on PGE2 synthesis by COX activation, could be a switch on mechanism that might lead mammary cells from normal to malignant phenotype. Moreover, mAchR coupling to distinct effectors might be associated with differences in aggressiveness of tumor cells.Fil: Español, Alejandro Javier. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Eiján, Ana M.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Mazzoni, Esteban. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Davel, Lilia. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Jasnis, Maria Adela. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Sacerdote de Lustig, Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaFil: Sales, Maria E.. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Oncología "Ángel H. Roffo"; ArgentinaUnidad documental simpl

Identification of a key oncogenic role of p63 in altered-FGFR3 tumors through inference of bladder cancer gene regulatory network and functional validations

The alteration of the receptor tyrosine kinase FGFR3 through activating mutations or translocations is one of the most common genetic events in bladder cancer (BLCA). Despite the demonstration of the oncogenic potential of such alterations, the gene regulatory network of an altered-FGFR3 in bladder cancer remains poorly characterized. We combined here a bioinformatic reverse-engineering inference approach together with in vitro and in vivo FGFR3-perturbation experiments to determine a BLCA regulatory network of transcription factors and co-factors (TFs/coTFs) that are driven by an altered-FGFR3 and critical for its oncogenic activity. Amongst them, we identified p63 in both non-muscle (NMIBC) and muscle invasive bladder cancers (MIBC) and further demonstrated that it mediates tumor growth, cell proliferation and migration of FGFR3-dependent bladder cancer cells. In Ta NMIBC, we observed both higher p63 activity and increased tendency of recurrence in tumors harboring a mutated-FGFR3 as compared to tumors with the wild-type receptor, suggesting that p63 activation by FGFR3 could favor recurrence. Our results elucidate an unexpected oncogenic key role of p63 in luminal papillary tumors bearing FGFR3 mutations and provide a global BLCA specific FGFR3-induced gene regulatory network that should allow a better understanding of FGFR3 induced oncogenic dependency that could have clinical applications.</div

Metastasis-suppressor NME1 controls the invasive switch of breast cancer by regulating MT1-MMP surface clearance

International audienceAbstract Membrane Type 1 Matrix Metalloprotease (MT1-MMP) contributes to the invasive progression of breast cancers by degrading extracellular matrix tissues. Nucleoside diphosphate kinase, NME1/NM23-H1, has been identified as a metastasis suppressor; however, its contribution to local invasion in breast cancer is not known. Here, we report that NME1 is up-regulated in ductal carcinoma in situ (DCIS) as compared to normal breast epithelial tissues. NME1 levels drop in microinvasive and invasive components of breast tumor cells relative to synchronous DCIS foci. We find a strong anti-correlation between NME1 and plasma membrane MT1-MMP levels in the invasive components of breast tumors, particularly in aggressive histological grade III and triple-negative breast cancers. Knockout of NME1 accelerates the invasive transition of breast tumors in the intraductal xenograft model. At the mechanistic level, we find that MT1-MMP, NME1 and dynamin-2, a GTPase known to require GTP production by NME1 for its membrane fission activity in the endocytic pathway, interact in clathrin-coated vesicles at the plasma membrane. Loss of NME1 function increases MT1-MMP surface levels by inhibiting endocytic clearance. As a consequence, the ECM degradation and invasive potentials of breast cancer cells are enhanced. This study identifies the down-modulation of NME1 as a potent driver of the in situ-to invasive transition during breast cancer progression