Tu1321 Effect of Granulocyte and Monocyte Adsorption Apheresis With Thiopurines in Patients With Early Diagnosed Crohn's Disease

BACKGROUND: While radiation therapy is considered useful in the treatment of gynecological malignant tumors such as uterine cervical cancer, it may cause radiation colitis and colitis-associated cancer.We have reported that extra-colonic cells contribute to abnormal repair of colonic tissues in radiation colitis.Here we show that evidence for latent precursor (gamma-H2AX signature) that may precede colitis-associated cancer, which has precursor lesions; aberrant crypt foci (ACF) commonly express markers of an activated DNA damage response.Our data indicate that chronic inflammation predisposed the tissue to cancer by inducing breakdown of an ATR/ATM-regulated DNA damage response network.METHODS: 1) Female rats were transplanted with male marrow (BMT) after sublethal irradiation.2) Colitis was induced by once focal colonic irradiation of 22.5 Gy Xray 5 weeks after the BMT for 8-9 weeks.The numbers of apoptosis and mitosis in the crypt and ACF in the colonic mucosa and histologic examination were estimated by H&E stained sections.3) Yand 12-chrompsome signals in the colonic mucosal cells were detected by FISH (Y Cy3 / 12 FITC).FISH Index: signal number ratio of Y-and 12-chromosome, fusion 4) P53, gamma-H2AX and gamma tubulin protein expression in the colonic tissue was detected by immunohistochemistry and western blotting methods.RESULTS: The number of apoptosis increased, and mitosis decreased in the crypt by 3 days after irradiation.The onset of colitis was at 7 -11 days after irradiation.Regenerative crypts were observed at 11 days after irradiation, after that focally ACF expressed and normal crypt repopulated.Twenty one out of 56 (46.4%)X-irradiated rats developed well differentiated adenocarcinomas in the colon 8-9 weeks after irradiation.FISH indices of ACF cells and normal crypt cells were 0.317+0.026and 0.065+0.014 in the crypt of colon 9 weeks after irradiation.Fusion chromosomes were observed in the crypt of adenocarcinoma.Moreover, we observed supernumerary centrosomes; gamma-tubulin over-expression, in the ACF.Gamma-H2AX expression was observed early in the irradiated crypts 1 and 6 hours after irradiation by immunohistochemistry and subsequently disappeared.Thereafter Ubiquitous gamma-H2AX protein expression with slightly p53 expression was appeared again in the ACF and the crypt of adenocarcinoma.Conclusion: These data indicated that evidence for latent precursor (gamma-H2AX signature) that may precede colitis-associated cancer with abnormal repair enhanced contribution of bone marrow-derived cells to colon.