Overexpression of cofilin 1 in prostate cancer and the corresponding clinical implications.

Cofilin 1 (CFL1) is a cytoskeletal protein and overexpression of the protein has been associated with aggressiveness in certain types of malignancies. The aim of the present study was to investigate the clinical implications of CFL1 expression in prostate cancer (PCa). Immunohistochemical analysis was performed using formalin-fixed paraffin-embedded tissue sections obtained from 111 patients with PCa and 47 patients with benign prostatic hyperplasia (BPH). In total, 78 (70.3%) out of 111 PCa tissues were found to express the CFL1 protein, while no expression was detected in BPH tissues. In addition, CFL1 was also observed to be significantly associated with the Gleason score (GS; <7 vs. ≥7; P<0.0001) and presence of lymph node metastasis (presence vs. absence; P<0.0001). However, there was no association between the expression of CFL1 and other clinicopathological variables, such as age (<69 years vs. ≥69 years; P=0.54), pre-operative prostate specific antigen level (<20 ng/ml vs. ≥20 ng/ml; P=0.45) and pathological stage (T2 vs. ≥T3a; P=0.055). In addition, 35 tissues (31.5%) were observed to possess a CFL1-positive mesenchyme. CFL1 expression was revealed to be an independent predictive factor for a high GS. The status of CFL1 expression in the mesenchyme also found to individually predict extraprostatic extension in PCa patients, based on multivariate analysis. The results of the present study indicated that CFL1 may specifically predict the development of PCa, and that the expression of CFL1 in the mesenchyme may be closely associated with the development of lymph node metastasis.