Molecular biological study on genesis and proliferation of renal malignant tumor

我们利用肾细胞癌患者手术切除的组织材料，采用分子生物学技术，旨在阐明肾恶性肿瘤的发生和增殖机制。第一年对8例肾细胞癌进行了染色体分析。3号和7号染色体的数值畸变发生率相对较高，而2号和6号染色体的结构畸变发生率较低，即长臂畸变。第二年，从这8个肿瘤中提取dna，然后评估各种癌基因的表达。但未见明显异常。另一方面，聚合酶链反应（PCR）法在50例膀胱癌中2例（4%）成功检测到H-ras癌基因过表达及其点突变。该方法通过PCR扩增包含密码子12的DNA片段，检测反应产物对限制性内切酶的敏感性，并用寡核苷酸探针进行斑点杂交试验。从新鲜或冷冻肿瘤组织、尿细胞和石蜡切片中分离的少量dna中可检测到点突变。这些结果表明，我们的方法不优于筛选，但在随访容易阳性病例非常有用。特别强调的是尿液细胞作为测试样本的可行性，因为它们对患者的无创性和易于重复。在第三年，我们努力尝试公布我们的结果。

We started this study in aiming to clarify the mechanism of genesis and proliferation of renal malignant tumors by means of molecular biology technique utilizing tissue materials surgically extirpated from the patients with renal cell carcinoma.In the 1st year, chromosomal analysis was carried out on 8 tumors of renal cell carcinoma. There were relatively high incidence of numerical aberrations in #3 and #7 chromosoms, and a lesser incidence of constitutional aberrations, i.e. long-arm aberrations in #2 and #6 chromosoms.In the 2nd year, DNAs were extracted from these 8 tumors and then subjected to evaluation of various oncogene expression. However, no significant abnormaility was found. On the other hand, it was successful to detect over expression of H-ras oncogene and its point mutation by means of polymerase chain reaction(PCR) method in 2 out of 50 bladder cancers (4%). In this method, the DNA segments including codon 12 were amplified by PCR, and the reaction products were examined for their susceptibility to the restriction enzyme, and by dot blot hybridization assay with oligonucleotide probes.Point mutations were detectable in small amounts of DNAs isolated from fresh or frozen tumor tissues, urine cells and paraffin sections. These results indicated that our method was not superior as screening,but very useful in following up the readily positive cases. Particularly emphasized is feasibility of urine cells as test samples because of their non invasiveness to the patients and easy repeatability.In the 3rd year, we made efforts to try to publicate our results.