The prognostic significance of Caspase-3 and survivin expression in colorectal cancer patients

Purpose: To investigate the expressions of caspase-3 and survivin in colorectal cancer patients and their possible associations with clinicopathological parameters and the oncological outcome. Methods: Between January 2008 and December 2011, 85 patients with sporadic colorectal cancer were submitted to colectomy with curative intent. Postoperatively, all patients were followed every three months up to the 36th month. Immunohistochemical detection of the apoptosis-related proteins was carried out on 4-mu m-thick deparaffinized sections from all primary tumors. Univariate and multivariate analyses were performed by using the R software for Windows, version 3.3.2. Results: Setting the cut-off point for caspase-3 positivity at 5%, 48% of the patients were characterized as caspase-3(+). Caspase-3 positivity was not found related either to any clinicopathological parameter or to the oncological outcome. Choosing simple survivin positivity as the cut-off point for its expression, 78% of the patients were considered as survivin(+). Survivin inexpression predisposed to poorly differentiated tumors of advanced T stage. However, neither a dismal nor a favorable prognostic role for survivin expression or inexpression was disclosed. By dividing all enrolled patients in four different groups, a trend for worse 3-year overall survival rate in the caspase-3(-)/survivin(-) subgroup of patients was noticed (p=0.067). Conclusion: Caspase-3 expression was unrelated to the oncological outcome in colorectal cancer patients. The proposed favorable prognostic role for survivin inexpression was not confirmed. On the contrary, survivin(-) tumors were mainly of poor differentiation and advanced T stage. An inverse relationship between caspase-3 and survivin expressions was also not confirmed. Future studies focusing on specific survivin isoforms expression or inexpression may give answers on apoptotic-antiapoptotic interactions on cancer cell death