RESUMEN
OBJECTIVE: To investigate the relationship between p53, COX-2, Bax, c-myc genes and colorectal carcinoma complicated with chronic schistosomiasis. METHODS: One hundred and sixty patients with colorectal carcinoma were selected and divided into two groups; a schistosomiasis group (colorectal carcinoma complicated with chronic schistosomiasis, n = 80) and a non-schistosomiasis group (colorectal carcinoma uncomplicated with chronic schistosomiasis, n = 80). The tissue microarray techniques and immunohistochemistry method were used in all the patients to detect the expressions of p53, COX-2, Bax and c-myc proteins. RESULTS: The positive rate and level of p53 protein expression in the schistosomiasis group were lower than those in the non-schistosomiasis group, but there were no significant differences between the two groups (both P > 0.05). The COX-2 protein in both groups was positive, but the positive expression level of COX-2 in the schistosomiasis group was higher than that in the nonschistosomiasis group, and there was a significant difference between the two groups (P < 0.01). The positive rate and level of Bax protein expression were not significantly different between the two groups (both P > 0.05). The positive rate of c-myc expression in the schistosomiasis group was higher than that in the non-schistosomiasis group, with a significant difference (P < 0.01), but the positive expression level was lower than that in the non-schistosomiasis group, and there was a significant difference between the two groups (P < 0.01). CONCLUSIONS: Schistosome infection may impact on the deficiency of p53 of human colorectal cancer cells. It may promote the excessive expression of COX-2 protein, which is an indirect carcinogenic factor. The expression of Bax gene has no correlation with schistosome infection. The schistosome chronic infection may cause a persistent low level expression of c-myc gene.