Effects of smoke and smokeless tobacco products on gene expression and cellular pathways in oral cavity cells

Tobacco exposure has been established to be a major risk factor for developing oral squamous cell carcinoma (OSCC). The purpose of this study is to identify potential biomarkers to distinguish the biological effectsof combustible tobacco products from that of non-combustible tobacco products using normal human gingival epithelial cells (HGEC), non-metastatic (101A) and metastatic (101B) OSCC cell lines. We performed microarray-based gene expression profiling and combined with Gene Set Enrichment Analysis (GSEA) to determine a set of genes that showed common biological pathways in human oral cavity cells when when exposed to cigarette smoke total particulate matter (TPM), whole-smoke conditioned media (WS-CM), smokeless tobacco extract in complete artificial saliva (ST/CAS), or nicotine (NIC) alone.