Fig. 4

TGFβ1 regulates the members of the MMP family. A The ROC curve analysis of the potential association of the expression levels of 20 MMP genes with biochemical recurrence-free survival (BRFS) in the TCGA PRAD gene expression dataset (n = 493). ROC analysis was conducted using easyROC web-tool [57]. B Correlation of MMP11 and MMP26 gene expression with TGFB1 mRNA levels in the PCa gene expression datasets TCGA PRAD (n = 493), MSKCC primary (n = 131), Broad/Cornell (n = 31), DKFZ (n = 118), and SMMU (n = 65) and non-cancerous tissues (MSKCC cohort, n = 29); *p < 0.05; n.s.- non significant. C PC3 and DU145 cells were treated with 5 ng/ml of TGFβ1 for 48 h, and MMP11 levels were analysed by qPCR. n ≥ 3; Error bars = SD; *p < 0.05; **p < 0.01. D Analysis of the previously published dataset [68] indicated that TGF-β signaling in stroma cells induces MMP expression in LNCaP cells. LNCaP cells overexpressing TGFB1 and co-cultured with stroma cells were compared to the control LNCaP co-cultured with stroma. *p < 0.05. E qPCR analysis of the relative MMP11 expression in LNCaP and PC3 cells upon knockdown of ALDH1A1 or ALDH1A3. Cells transfected with scrambled siRNA (siScr) were used as controls. n = 3; Error bars = SD; *p < 0.05; **p < 0.01; n.s.- non significant. F qPCR analysis of the relative MMP11, ALDH1A1 and ALDH1A3 expression in LNCaP and PC3 cells upon MMP11 knockdown. Cells transfected with scrambled siRNA (siScr) were used as controls. n ≥ 3; Error bars = SD; *p < 0.05; **p < 0.01; ***p < 0.001. G Relative cell radiosensitivity was analysed by 2D radiobiological colony forming assay after siRNA-mediated knockdown of MMP11 in LNCaP and PC3 cells. Cells transfected with scrambled (Scr) siRNA were used as controls. n = 3; Error bars = SD; **p < 0.01. H PC3 cells were cultured either under 2D conventional adherent conditions, in the polymer-based microcapsules mimicking mechanical stress within tumors [42], or in 3D anchorage-free cultures as a model of the intermediate stage of metastasis, circulating tumor cells (CTC). In all conditions, cells were kept in the same culture media. At day 3, the cells were collected, and relative gene expression of TGFB1, MMP11, ALDHA1 and ALDHA3 was analysed by qPCR. n ≥ 3; Error bars = SD; *p < 0.05; ***p < 0.001. I ALDH1A1 regulates TGFB1 expression in androgen-sensitive cells through AR- and RA-dependent mechanisms. In contrast, the interplay between TGF-β1 and MMP11 is present in the androgen-sensitive and castration-resistant models of PCa (like in LNCaP and PC3 cells, respectively)