RT Journal Article SR Electronic T1 DNMT3L Is a Novel Marker and Is Essential for the Growth of Human Embryonal Carcinoma JF Clinical Cancer Research JO Clin Cancer Res FD American Association for Cancer Research SP 2751 OP 2759 DO 10.1158/1078-0432.CCR-09-3338 VO 16 IS 10 A1 Minami, Kahori A1 Chano, Tokuhiro A1 Kawakami, Takahiro A1 Ushida, Hiroshi A1 Kushima, Ryoji A1 Okabe, Hidetoshi A1 Okada, Yusaku A1 Okamoto, Keisei YR 2010 UL http://clincancerres.aacrjournals.org/content/16/10/2751.abstract AB Purpose: Testicular germ cell tumors (TGCT) have a unique epigenetic profile distinct from that of other types of cancer. Elucidation of these properties has a potential to identify novel markers for TGCTs.Experimental Design: We conducted comprehensive analysis of DNA methyltransferase (DNMT) gene expression in TGCTs. Based on the expression profiles of DNMT genes in TGCTs, we generated a rabbit polyclonal anti-human DNMT3L antibody. We then studied the role of DNMT3L in TGCTs by the treatment of two embryonal carcinoma (EC) cell lines with a small interfering RNA system. Finally, we evaluated the immunohistochemical detection of DNMT3L in TGCT tissues. We also compared the patterns of DNMT3L immunohistochemistry with those of CD30 and SOX2.Results: Among the DNMT genes, we found that mRNA for DNMT3L was specifically expressed in TGCTs, but neither in normal testicular tissues nor in cancer cells of somatic tissue origin. DNMT3L protein was strongly expressed in two EC cell lines, but not in the cell lines of somatic tissue origin. Transfection of small interfering RNA for DNMT3L significantly reduced DNMT3L expression and resulted in growth suppression and apoptosis in EC cells. Immunohistochemical analysis showed that DNMT3L protein was present only in EC cells, but not in the other types of TGCT components and cancer cells of somatic tissue origin. DNMT3L staining was more prominent and specific than CD30 or SOX2 staining for detecting EC cells.Conclusion: DNMT3L is a novel marker and is essential for the growth of human embryonal carcinoma. Clin Cancer Res; 16(10); 2751–9. ©2010 AACR.