[Effect of Caveolin-1 on growth and apoptosis of human breast carcinoma cell line Hs578T/Dox].

BACKGROUND AND OBJECTIVE

Caveolin-1 is a marker protein of caveolae which is related with oncogenesis as a signal transduction hinge. This study was to investigate the effect of Caveolin-1 on the growth and apoptosis of doxorubicin-resistant human breast carcinoma cell line Hs578T/Dox.

METHODS

Plasmids pCI-neo-caveolin-1 and pCI-neo-vector (control) were transfected into Hs578T/Dox cells, respectively. The expression of Caveolin-1 was detected by Western blot. Cell proliferation was detected by MTT assay. Cell cycle was detected by flow cytometry (FCM). Colony formation potential on soft agar was evaluated. Cell apoptosis was detected by FCM when cells were cultured for 48 h or cultured with staurosporine for 8 h.

RESULTS

Caveolin-1 was overexpressed in Hs578T/Dox-cav-1 cells. The proliferation of Hs578T/Dox-cav-1 cells was obviously promoted when compared with that of Hs578T/Dox-vector cells (P<0.01). Colony size was larger in Hs578T/Dox-cav-1 group than in Hs578T/Dox-vector group. More colonies were formed in Hs578T/Dox-cav-1 group as compare with those in Hs578T/Dox-vector group (983.6+/-75.0 vs. 700.8+/-78.9, P<0.01). The proportions of cells at S and G2/M phases were higher in Hs578T/Dox-cav-1 group than in Hs578T/Dox-vector group. The proliferation rate of Hs578T/Dox-cav-1 cells was also higher than that of Hs578T/Dox-vector cells [(76.6+/-4.0)% vs. (58.0+/-4.1)%]. Over-expressed Caveolin-1 significantly reduced apoptosis index when the cells were cultured for 48 h [(5.7+/-0.5)% vs. (11.3+/-0.8)%] or cultured with staurosporine for 8 h [(13.8+/-1.2)% vs (21.4+/-1.9)%].

CONCLUSION

Overexpression of Caveolin-1 protein may promote the growth and anti-apoptosis ability of Hs578T/Dox cells.