Risk factors for developing colorectal cancer in Japanese patients with ulcerative colitis: a retrospective observational study-CAPITAL (Cohort and Practice for IBD total management in Kyoto-Shiga Links) study I.

BACKGROUND AND AIMS: Patients with ulcerative colitis (UC) are at risk for developing colorectal cancer (CRC), despite the development of new therapeutic agents. Stratification of the individual UC-patient's risk would be helpful to validate the risk factors for CRC. The aim of this study was to evaluate the risk factors for the development of CRC in a large cohort of patients with UC. METHODS: Data were obtained from 12 hospitals in the Kyoto-Shiga region during 2003-2013. We performed a retrospective cohort study of 2137 patients with UC. RESULTS: In total, 60 lesions of CRC were detected in 43 (2.0%) of 2137 patients. 30 of the 43 patients were male. The median age was 53 years. The median duration of disease was 13 years, and 67.4% of these patients had a disease duration >10 years. Of the 43 patients, 34 (79.1%) had extensive colitis. Primary sclerosing cholangitis was detected in 2 patients (4.7%). The median corticosteroids (CS) dose was 6.4 g, and 4 patients were treated with a total of more than 10 g of CS. 18 of these patients underwent more than 1 year CS treatment. Of all 60 CRC lesions, 43 (71.7%) were located in the distal colon and 35 (58.3%) were of the superficial type. Moreover, the stage of CRC was stage 0 or I in 55.8% of the 43 patients with CRC. Multivariate analysis suggested that extensive colitis could be a risk factor for the development of advanced CRC in patients with UC. CONCLUSIONS: Our findings indicated that male, extensive colitis, long-term duration of UC and family history of CRC, but not concomitant primary sclerosing cholangitis, are important factors for predicting CRC in Japanese patients with UC. Moreover, long-standing extensive colitis might contribute to the progression of CRC. Further studies are required to establish CRC surveillance in Japanese patients with UC.

Apigenin induces cell cycle arrest and p21/WAF1 expression in a p53-independent pathway.

Apigenin, a common dietary flavonoid, has been shown to induce cell growth-inhibition and cell cycle arrest in many cancer cell lines. One important effect of apigenin is to increase the stability of the tumor suppressor p53 in normal cells. Therefore, apigenin is expected to play a large role in cancer prevention by modifying the effects of p53 protein. However, the mechanisms of apigenin's effects on p53-mutant cancer cells have not been revealed yet. We assessed the influence of apigenin on cell growth and the cell cycle in p53-mutant cell lines. Treatment with apigenin resulted in growth-inhibition and G2/M phase arrest in two p53-mutant cancer cell lines, HT-29 and MG63. These effects were associated with a marked increase in the protein expression of p21/WAF1. We have shown that p21/WAF1 mRNA expression was also markedly increased by treatment with apigenin in a dose- and time-dependent manner. However, we could not detect p21/WAF1 promoter activity following treatment with apigenin. Similarly, promoter activity from pG13-Luc, a p53-responsive promoter plasmid, was not activated by treatment with apigenin with or without p53 protein expression. These results suggest that there is a p53-independent pathway for apigenin in p53-mutant cell lines, which induces p21/WAF1 expression and growth-inhibition. Apigenin may be a useful chemopreventive agent not only in wild-type p53 status, but also in cancer with mutant p53.

Genistein induces Gadd45 gene and G2/M cell cycle arrest in the DU145 human prostate cancer cell line.

Genistein is the most abundant isoflavone of soybeans and has been shown to cause growth arrest in various human cancer cell lines. However, the precise mechanism for this is still unclear. We report here that the growth arrest and DNA damage-inducible gene 45 (gadd45) gene is induced by genistein via its promoter in a DU145 human prostate cancer cell line. The binding of transcription factor nuclear factor-Y to the CCAAT site of the gadd45 promoter appears to be important for this activation by genistein.