Caveolin-1 haploinsufficiency leads to partial transformation of human breast epithelial cells.

ABSTRACT

BACKGROUND: Caveolin-1 (Cav-1), a principal component of caveolae membranes, may function as a tumor suppressor in several types of human cancer. MATERIALS AND METHODS: In this report, we employed a retrovirus-mediated poly-A gene trapping approach to inactivate expression of genes that may be involved in transformation of mammary cells and screened for cell growth in soft agar. RESULTS: We found two anchorage-independent clones (ST1 and ST3) that expressed reduced levels (approximately 50%) of Cav-1 mRNA and protein, suggesting the inactivation of one allele of Cav gene. However, haploinsufficiency of Cav-1 expression did not induce significant tumor formation when tested in nude mice. CONCLUSION: Cav-1 haploinsufficiency in human breast epithelial cells can lead to partial transformation.