Clonal Origin Study Of Clear Cell Renal Carcinoma By X-chromosome Inactivation Pattern

Objective: Clear cell renal carcinoma (cc-RCC) is one of the most common pathological subtypes of kidney cancer .To assess the clonal origin of renal clear cell carcinomas by the study of X-chromosome inactivation pattern in female clear cell renal carcinomas and normal renal tissues.Methods: Tissue DNA from samples of 15 female clear cell renal carcinoma and the corresponding normal renal tissues was extracted,and digest with methylation sensitive restriction endonuclease HhaI.HUMARA fragment was amplified using polymerase chain reaction (PCR) method and PCR product was electrophoresed.Clonality was assessed by observing the electrophoresis bands.Results: Heterozygotic rate of HUMARA was 86.7%.Monoclonal rates of clear cell renal carcinomas and normal renal tissues were 84.6% and 7.7%,respectively, the difference was statistically significant(P=0.00).There was no significant difference in refer to clinical stages for monoclonal rates of clear renal cell carcinomas,with pT1 in 80%(4/5),pT2 in 100%(4/4) and pT3 in 75%(3/4), (P>0.05). And the monoclonal rate in tumors of G1 (75%,3/4),G2 (83%,5/6) and G3(100%,3/3) was also not significantly different (P>0.05).Conclusion: Clear cell renal carcinoma is a kind of monoclonal origin tumor and there is no significant associations between clonality and tumor staging and grading.