Schmidt B, Ackermann R, Hartmann M, Strohmeyer T
Department of Urology, Heinrich-Heine-University, Düsseldorf, Germany.
J Urol. 1997 Nov;158(5):2000-5. doi: 10.1016/s0022-5347(01)64201-0.
The putative metastasis suppressor genes nm23-H1, nm23-H2 and the c-myc proto-oncogene were investigated in testicular germ cell tumors (GCTs) using Southern and Northern blotting as well as semiquantitative reverse transcription polymerase chain reaction (RT-PCR) and single strand conformation polymorphism (SSCP) analysis. When studying Bgl II RFLPs, allelic losses of the nm23 gene were found in 3/12 (25%) informative tumors, and all 3 had lymph node and/or distant metastases. A 2 to 7 fold nm23 mRNA overexpression was found in 22/34 (64.7%) tumors examined. RT-PCR revealed that this phenomenon is mainly a consequence of nm23-H2 overexpression. Overexpression of both the H1 and the H2 gene was predominantly found in the seminoma subtype and was not associated with tumor stage. Only 1/25 tumors, a seminoma with distant metastases, had a point mutation in the coding region of the nm23-H2 gene as demonstrated by SSCP analysis. None of the 8 seminomas and only 1/13 non-seminomas had c-myc overexpression. No abnormalities of the c-myc gene could be detected on the DNA level. Despite the fact that in previous investigations nm23-H2 was demonstrated to be a putative transcription factor for c-myc, no coexpression of c-myc and nm23-H2 was found by quantitative RT-PCR in this study.
采用Southern印迹法、Northern印迹法、半定量逆转录聚合酶链反应（RT-PCR）及单链构象多态性（SSCP）分析，对睾丸生殖细胞肿瘤（GCT）中的假定转移抑制基因nm23-H1、nm23-H2和原癌基因c-myc进行了研究。在研究Bgl II限制性片段长度多态性（RFLP）时，在12例信息充分的肿瘤中有3例（25%）发现nm23基因的等位基因缺失，且这3例均有淋巴结和/或远处转移。在所检测的34例肿瘤中有22例（64.7%）发现nm23 mRNA过表达2至7倍。RT-PCR显示，这种现象主要是nm23-H2过表达的结果。H1和H2基因的过表达主要见于精原细胞瘤亚型，且与肿瘤分期无关。如SSCP分析所示，在25例肿瘤中只有1例有远处转移的精原细胞瘤在nm23-H2基因编码区存在点突变。8例精原细胞瘤中无一例、13例非精原细胞瘤中仅1例有c-myc过表达。在DNA水平未检测到c-myc基因异常。尽管在先前的研究中nm23-H2被证明是c-myc的假定转录因子，但在本研究中通过定量RT-PCR未发现c-myc与nm23-H2共表达。
