Figure 4.

Inhibition of CBP and RFPL-3 suppresses the proliferation of breast cancer cells with cocultured ASCs following decreases in hTERT transcription in vitro and in vivo. (a) Real-time PCR and western blot analysis of the expression of hTERT mRNA and protein in MDA-MB-231 cells transfected with CBP siRNA and nonspecific siRNA. (b–c) The transfected MDA-MB-231 cells were treated with culture supernatant from ASCs, and the cell viability and proliferation were analyzed using CCK-8 assays and dsDNA quantification. (d) MDA-MB-231 cells were transfected with RFPL-3 siRNA and nonspecific siRNA, and then, hTERT mRNA and protein were examined using real-time-PCR and Western blot. (e–f) MDA-MB-231 cells transfected as above were treated with culture supernatant from ASCs, and then, the cell viability and proliferation were examined by CCK-8 assays and dsDNA quantification. (g) Tumor grafts up to 21 days after nude mice were injected with ASCs and cell lines stably expressing CBP shRNA, scramble shRNA, CBP shRNA + empty vector, and CBP shRNA + hTERT. (h) Tumor growth curves in nude mice. (i) The mean tumor weights 21 days after coinjection. (J) Western blot analysis of the expression of CBP and hTERT in tumor xenografts. ∗P < 0.05, ∗∗P < 0.01, ∗∗∗P < 0.001.