DNMT3B and nonpapillary renal cell carcinoma: Indeed, our results from real-time PCR analysis, which indicate that the relative abundance of DNMT3B4 mRNA to total DNMT3B mRNA is 1 to 1000, supports the hypothesis that while there may be no difference in DNMT3B mRNA expression between ccRCC tissue and normal tissue, DNMT3B4 overexpression plays an important role in tumorigenesis is in ccRCC.