Loss of fragile histidine triad expression in colorectal carcinoma

To investigate the expression of fragile histidine triad (FHIT) gene protein, FHIT and the possible relationship between FHIT expression and clinicopathological indices in colorectal carcinoma.

Detecting FHIT protein expression in 60 cases of formalin-fixed, paraffin-embedded colorectal carcinoma by citrate-microwave-SP immunohistochemical method, and analyzing its relationship to histological grade, Dukes' stage and 5-year survival rate.

55% of the carcinomas showed a marked loss or absence of FHIT expression compared with their matched normal mucosa. Carcinomas with reduced expression of FHIT correlated with their histological grade, Dukes' stage (P < 0.05) and 5-year survival rate. The distribution of decreased expression of FHIT was 7/16 in grade I carcinoma, 14/30 in grade II, 12/14 in grade III, respectively. The correlation between decreased expression of FHIT and Dukes' staging was 5/11 in stage A, 12/28 in stage B, and 16/21 in stage C. The difference between stage A, B with no lymph nodes metastases and the stage C with lymph nodes metastases was of significance (P < 0.05). The follow-up data of 39 cases showed that in the 5-year survival group, 13/25 were of the low FHIT expression carcinomas, while in 5-year deceased group 12/14 were of the low FHIT expression carcinomas (P < 0.05).

The reduced expression of FHIT may be associated with decreasing differentiation, metastasis and 5-year survival rate in colorectal carcinoma. It is suggested that decreased FHIT expression plays an important role in the development and progression of the tumor, and thus may become a new prognostic marker in colorectal carcinoma.