BCL2 and breast cancer: Moreover, it has been reported that the development of pregnancy-dependent mammary tumors to malignant tumors was accompanied by an intense expression of Bcl-2 and was associated with the overexpression of PKCε [167] In addition, it has recently been found that overexpression of PKCε in MCF-7 cells increased Bcl-2 mRNA and protein level and, concomitantly, decreased the proapoptotic protein Bid.