Although clinical observation can often reveal individual differences in the severity of lung fibrosis after radiation therapy, the actual influences of inherent individual factor is difficult to determine a clinical setting. In this paper, the usefulness of mouse model for research of heterogeneity in response of cancer treatment was investigated.C57BL/6J and C3H/HeMs mice were used for pathological and transcriotional experiments. The thorax of mice was locally irradiated at a dose of 10 or 20 Gy. Four-fold more CD44 positive cells had accumulated in the lungs of C3H/HeMs than of C57BL/6J mice. At sites of lung inflammation, HA accumulated at 12 hours after irradiation and the rapid resolution was achieved within 2 weeks in the lungs in both C57BL/6J mice and C3H/HheMs mice. An immunochemical investigation of C57BL/6J mice lungs revealed dense collagen accumulation at 8 weeks. The expression of Cap1, II18 and Rad51ap1 was constantly higher for 72 hours in C3H/HeMs mice than C57BL/6J mice. The expression of Mmp12 and Per3 was more induced in C3H/HeMs mice than C57BL/6J mice at 12 hours after irradiation. The expresion of Ltf was especially higher at 1 hour after iiradiation and that of Ifi202a was more induced at 72 hour in C57BL/6J mice than C3H/HeMs mice. Investigations into the mechanism of radiation-induced lung damage using animal models showed a powerful impact upon molecular studies of individual radiosensitivity.Mouse Models of Human Cancer (B7
