Identification of high risk group for prostate cancer by investigation of vitamin D receptor gene

首先，利用介子8和外显子8之间的3个PCR-RFLP标记检测了健康志愿者和泌尿系统疾病（包括前列腺癌、其他癌症和尿石症）患者维生素D受体基因的单核苷酸多态性（snp）。3个酶切位点为ApaI、BamHI和TaqI。101份对照样品的基因型分别为：TaqI为TT（74.3%）、TT（24.8%）和TT (1.0%)， BamHI为BB（4.0%）、BB（27.7%）和BB (68.3%)， ApaI为AA（11.9%）、AA（43.6%）和AA（44.6%）。在尿石症患者中，该等位基因被认为是疾病复发的危险因素。其次，对40例肾细胞癌患者进行6号染色体缺失定位。对D6S975 ~ D6S1577 6q、22.3 cM的6个微卫星标记进行了分析。40例患者中有13例（33%）在5项标志物中至少有1项存在LOH。在LOH病例中，D6S311的17.1 cM区域和/或D6S441的9.8 cM区域的LOH发生率最高。在同样的分析中，在前列腺癌病例中没有发现显著的发现。再次，采用PCR-SSCP对BRG1基因进行突变分析。BRG1基因位于19p，在前列腺癌中经常出现缺失。BRG1基因的基因型在第9外显子出现变异。直接测序显示T/T、T/C、C/C基因SNP33978。T/T基因型SNP33978患者的诊断年龄明显较年轻（p=0.03）。T/T基因型的年轻患者（年龄<62岁）比T/C或C/C基因型的患者更容易发生高级别、晚期和转移性肿瘤（p=0.0134）。分析几种种系snp的变异和组合，有助于预防医学、制定治疗方案和预测癌症患者的预后。

Firstly, single nucleotide polymorphisms (SNPs) of vitamin D receptor gene were examined using three PCR-RFLP markers spanning between intron 8 and exon 8 in the healthy volunteers and the patients with urological problems including prostate cancer, other cancers and urolithiasis. Three restriction sites were ApaI, BamHI and TaqI. Genotypes in 101 of control samples were, TT (74.3%), Tt (24.8%) and tt (1.0%) for TaqI, BB (4.0%), Bb (27.7%) and bb (68.3%) for BamHI, AA (11.9%), Aa (43.6%), and aa (44.6%) for ApaI. In the patient with urolithiasis, t allele was indicated as a risk factor for the recurrent disease. Secondly, deletion mapping of chromosome 6 in 40 cases of renal cell carcinoma was performed. Six microsatellite markers on 6q, 22.3 cM from D6S975 to D6S1577 were analyzed. 13 cases out of 40 (33%) were found to have LOH at least one out of 5 markers. Among the cases with LOH, LOH in the 17.1 cM region with D6S311 and/or the 9.8 cM region with D6S441 were frequently observed. No remarkable findings were seen in prostate cancer cases in the same analysis. Thirdly, mutation analysis of BRG1 gene using PCR-SSCP was performed. BRG1 gene is located at 19p where deletion is frequently seen in prostate cancer. Variation of the genotype of BRG1 gene was observed in exon 9. Direct sequencing revealed SNP33978 of T/T, T/C, C/C. The patients with T/T genotype of SNP33978 were diagnosed at significantly younger ages (p=0.03). Young patients (age<62 years) with T/T genotype were more frequently to have high grade, advanced stage and metastatic tumors than patients with the T/C or C/C genotype (p=0.0134). It was suggested to be useful in preventive medicine, in decision making of therapeutic options and in predicting prognosis patients with cancer to analyze the variation and the combination of several germline SNPs.