Sinonasal IP is histologically benign but shows a propensity for malignant transformation. Survivin, a member of the inhibitor of the apoptosis family of proteins that controls cell division, apoptosis, metastasis, and, probably, also neoangiogenesis, is overexpressed in virtually all human cancers. Overexpression of the multidomain protein cortactin has also been associated with increased cell migration, invasion, and metastatic potential in several malignancies.
The aim of the present study was to preliminarily investigate survival and cortactin expression in a consecutive series of sinonasal IPs and IP-associated SCC.
Immunohistochemical expression of nuclear survival and cortactin was measured in 19 consecutive sinonasal IPs and 3 IP-associated SCCs.
The mean ± standard deviation nuclear survival expression was 9.4 ± 9.2% and 31.7% ± 15.4% in sinonasal IPs and SCCs, respectively. Results of cortactin immunostaining were strongly positive in the cytoplasm of both sinonasal IPs and SCCs: no significant difference emerged between the IP and SCC epithelial components.
Nuclear survival expression was significantly higher in SCCs than in IPs. Prospective, multi-institutional prognostic studies, preferably on an international scale, are needed to confirm survivin’s role in IP malignant transformation.