BCL2 and breast adenocarcinoma: Baseline expression analysis by quantitative RT-PCR revealed that BCL-2 mRNA is significantly overexpressed in MCF-7 (human breast adenocarcinoma) and HepG2 (human hepatocellular carcinoma) cells relative to HFL-1 (normal human lung fibroblasts), indicating these cell lines are suitable models for investigating BCL-2-targeted gene knockdown (Figure 2A).