Fig. 6: CAFs increased ERβ expression via IGF-1/AKT/c-Jun signalling.

a The expression of IGF-1R and PI3K and the phosphorylation of the IGF-1R and AKT proteins were increased after co-culture, but these effects were reversed by blocking IGF-1. b Western blotting showed that adding the IGF-1R inhibitor AG (1 μM) to the co-culture system could partially reverse CAF-mediated increases in the protein expression of ERβ and Bcl-2 and the phosphorylation of IGF-1R and AKT. c Western blotting showed that ERβ and Bcl-2 expression and AKT phosphorylation were decreased when the cells were pretreated with the AKT inhibitor LY (10 μM) in the co-culture system. d qRT-PCR results showed changes in ERβ and Bcl-2 mRNA expression in BCa cells after co-culture upon pretreatment with AG (1 μM) and LY (10 μM) for 1 h before co-culture. The mean expression value of the control cells (T24, 5637) was defined as 1.0. e Both AG and LY can partially reverse the effects of CAFs on BCa cell resistance to cisplatin-induced apoptosis. f Phosphorylation of c-Jun was detected by western blotting in each group. g The cells were treated with or without IGF-1 for 8 h. Then, the cells were harvested and subjected to chromatin ChIP with anti-c-Jun or control IgG, followed by qRT-PCR. h ChIP products were measured by real-time PCR. The expression value in the control group was defined as 1. All procedures were conducted after cells were cultured in an appropriate concentration of cisplatin (T24, 25 mg/L; 5637, 6 mg/L). Data are presented as the mean ± SD. *P < 0.05