A gene expression profile for non-smoking and non-drinking patients with head and neck cancer

OBJECTIVE: A small subset of patients with head and neck squamous cell carcinoma are non-smoking and nondrinking and have distinct clinical characteristics. We aimed to identify a possible different genetic profile for these patients when compared with their smoking and drinking counterparts. MATERIALS AND METHODS: The gene expression data previously detected from primary tumors located in the oral cavity and oropharynx, using DNA microarray was analyzed for their differential expression between non-smoking and non-drinking patients (n = 15) and smoking and drinking patients (n = 89). Student's T-test (P < 0.05) and 10-fold cross-validation procedure (100 times repeated) were performed to determine differentially expressed genes. RESULTS: Non-smoking and non-drinking patients were older, mostly female and had oral cavity-localized tumors, whereas smoking and drinking patients were younger male patients with 81% oral cavity and 19% oropharynx tumors. A set of 49 differentially expressed genes were detected. Among others, seven genes related to interferon-c were upregulated and two genes linked to NFKB pathway were downregulated. CONCLUSIONS: Differentially expressed genes in nonsmoking and non-drinking patients possibly indicate the presence of a different cellular response to carcinogenic events in these patients. Further studies are warranted to validate this gene set and explore possible therapeutic implications to improve prognosis for these patients. Oral Diseases (2012) 18, 178-183