An altered apoptotic response represents a pivotal feature of cancer, contributing to carcinogenesis and resistance to therapy. Our recent studies demonstrate high expression of Mcl-1, bclxL and bclw transcripts in oral cancer cell lines (Gurav, Dwivedi) and in immortalized fetal buccal mucosa cell line (FBM) using the Ribonuclease Protection assay. In addition 65% of the oral tumor samples examined by RPA assay also exhibited upregulation of Mcl-1(L) transcript which is an anti-apoptotic form.

Defects in cellular apoptosis and proliferation play an important role in tumor pathogenesis allowing neoplastic cells to survive beyond their normal intended lifespan. Our earlier studies indicate an inhibition of cell death, enhancement of proliferation and frequent overexpression of p53, bcl-2 and bax, members of the p53-dependent apoptotic pathway in the transition from oral lesions to oral cancer. The present project proposes to determine the expression pattern of apoptotic genes involved in the intrinsic and extrinsic cell death pathways (Fig.1) (viz.