High expression of survivin and its splice variants survivin ΔEx3 and survivin 2 B in oral cancers.

Objectives We have previously reported inactivation of p53 in 46% of Indian patients with oral cancer. Survivin, a p53 target gene and an inhibitor of apoptosis protein (IAP), is overexpressed in several cancers, including oral cancers. Studies assessing the role of survivin and its splice variants in oral cancers are, however, rare. Materials and Methods The expression of 6 survivin isoforms in 4 oral cancer cell lines (AW8507, AW13516, UPCI-SCC040, UPCI-SCC029 B), a dysplastic oral cell line (DOK), 75 paired oral tumor and adjacent normal tissues, and 12 normal oral tissue samples from healthy individuals was analyzed by real-time PCR. The expression was correlated with clinicopathologic parameters, which included age, sex, tumor-node-metastasis (TNM) staging, tobacco and/or alcohol consumption, site, and differentiation status of tumor. Results This is the first study to find overexpression of the 6 characterized survivin isoforms in oral cancers compared with normal tissues ( P P P P Conclusions Our studies thus indicate that oral cancers overexpress the antiapoptotic survivin variants, which exhibit an association with advanced tumor stage, implying a role for these variants in oral tumorigenesis.