Caveolae/caveolin-1 are important modulators of store-operated calcium entry in Hs578/T breast cancer cells.
Caveolin-1 is a principal component of caveolae, invaginations of the plasma membrane that are enriched in cholesterol and sphingolipids. The expression of caveolin-1 has been shown to be tightly correlated to the progression of breast cancer tumors. However, the consequences of altered caveolin-1 expression during tumor progression still remain unclear. Modification of caveolin-1 expression modulates store-operated Ca(2+) entry (SOCE) in various cell types. SOCE is a ubiquitous Ca(2+) entry pathway that previous studies have linked to apoptosis and tumor progression in prostate cancer cells. In this study, we tested the effect of altering caveolin-1 expression on SOCE in Hs578/T breast cancer cells. Through overexpression of caveolin-1 and small hairpin RNA (shRNA) knockdown, we generated four stable cell lines that have 3 different caveolin-1 protein levels. Cav-1 overexpression could increase SOCE activity, while knockdown of caveolin-1 significantly reduced SOCE activity. These functional consequences were correlated with changes in caveolae number in Hs578/T cells. Our results suggest alteration of SOCE by caveolin-1 expression changes could be one of the mechanisms contributing to the progression of breast cancer.
Zhu
Hua
H
The Cancer Institute of New Jersey, University of Medicine and Dentistry of New Jersey, New Brunswick 08901, USA. Zhuhu2@umdnj.edu
Weisleder
Noah
N
Wu
Ping
P
Cai
Chuanxi
C
Chen
Jian-wen
JW
D001943:Breast Neoplasms / Q000378:metabolism* / Q000648:ultrastructure; D002118:Calcium / Q000378:metabolism*; D021941:Caveolae / Q000378:metabolism* / Q000648:ultrastructure; D051242:Caveolin 1 / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D034622:RNA Interference
C495540:CAV1 protein, human; D051242:Caveolin 1; D002118:Calcium