BCL2 and cancer: For example, Warenius et al reported that upregulated cyclinD1 might be responsible for cis-diamminedichloroplatinum (CDDP) resistance in cancer cells [20], and Zhang et al suggested that the cell cycle inhibitor p21waf1 might synergize with bcl-2 to confer drug resistance by inhibiting anti-cancer drug induced-apoptosis [21].