AIM: To investigate the expression of fragile histidine triad (FHIT) protein in 64 patients with ulcerative colitis (UC) and Crohn’s disease (CD), and its relation with clinicopathological data. METHODS: Rabbit-anti-FHIT antibody was used to detect FHIT protein expression in 64 formalin-fixed, paraffin-embedded tissue specimens of inflammatory bowel disease (IBD) by citrate-microwave-streptavidin (SP)-HRP immunohistochemical method. RESULTS: The positive FHIT protein expression was 22.79% ± 16.16%, 42.14% ± 16.82% in active and remittent phases of UC, 36.07% ± 19.23% in CD, and 57.05% ± 8.86% in normal colon mucosa. Statistically signifi cant differences in FHIT protein expression were observed between the active and remittent phases of UC, between the active phase of UC and normal colon mucosa, as well as between the remittent phase of UC and normal colon mucosa, and between CD and normal colon mucosa. CONCLUSION: Our results show that FHIT protein expression is completely absent or reduced in IBD, suggesting that the FHIT gene might be associated with the oncogenesis and progression of IBD, an early event from in? ammatory conditions to carcinoma in IBD. AIM: To investigate the expression of fragile histidine triad (FHIT) protein in 64 patients with ulcerative colitis (UC) and Crohn’s disease (CD), and its relation with clinicopathological data. METHODS: Rabbit-anti-FHIT antibody was used to detect FHIT RESULTS: The positive FHIT protein expression was 22.79% ± 16.16%, 42.14%. The protein expression was 64 formalin-fixed, paraffin-embedded tissue specimens of inflammatory bowel disease (IBD) by citrate-microwave- streptavidin (SP) ± 16.82% in active and remittent phases of UC, 36.07% ± 19.23% in CD, and 57.05% ± 8.86% in normal colon mucosa. Statistically signifi cant differences in FHIT protein expression were observed between the active and remittent phases of UC, between the active phase of UC and normal colon mucosa, as well as between the remittent phase of UC and normal colon mucosa, and between CD and normal colon mucosa. CONCLUSION: Our results show that FHIT protein expression is completely absen suggesting that the FHIT gene might be associated with the oncogenesis and progression of IBD, an early event from in? ammatory conditions to carcinoma in IBD.