ABSTRACT
Objective: To detect the dynamic change of expression of CD133, a marker of liver cancer stem cell, at different stages of liver carcinogenesis induced by chemicals in C57BL/6J mice. Methods: The tumorigenesis and the growth of chemical (diethylnirtosamine/carbon tetrachloride/ethanol)-induced primary HCC (hepatocellular carcinoma) in 50 male C57BL/6J mice were observed. Another 45 male C57BL/6J mice which had not been exposed to carcinogenic chemicals were used as the normal controls. The mice were randomly sacrificed every two weeks, and the liver tissues were removed to observe the change of pathology. The expression of CD133 mRNA was detected by RFQ-PCR (real-time fluorescent quantitative PCR), and the expression of CD133 protein was detected by immunohistochemistry and Western blotting. The percentage of CD133-positive cells was analyzed by FCM (flow cytometry). Results: The primary HCC was successfully induced in male C57BL/6J mice after chemical intervention for 20 weeks. The results of RFQ-PCR and FCM showed that the expression level of CD133 in the chemicalinduced group was obviously higher than that in the normal control group after 8 weeks (P < 0.05, P < 0.001). The expression level of CD133 kept on rising in the chemical-induced group as time progressed, and it was significantly higher at the 16th week than at earlier stages (P < 0.001). Western blotting result showed that the CD133 weak expression could be observed at the 4th week. As time progressed, the expression level of CD133 protein was gradually increased. The result of immunohistochemistry showed that the expressions of CD133 in the chemical-induced group were weakly, moderately and strongly positive at the 8th, 16th and 20th week, respectively; while the expression of CD133 was negative in the normal control group. Conclusion: The liver cancer stem cell marker CD133 is involved in the development and progression of liver cancer, and its expression level is gradually increased in the process of carcinogenesis. Copyright © 2012 by TUMOR.