BCL2 and cancer: Brefeldin A exhibited significant antitumor activity, its treatment causes apoptosis in several human cancer cell lines e.g. human glioblastoma (SA4, SA146, U87MG) and colon cancer cells (HCT-116) via arresting G0/G1 phase of cell cycle independent of Bcl-2/ Bax Mcl-1 and p53 [5].