Identification of metastasis suppressor genes for prostate cancer and establishment of genetic diagnosis and therapeutic system of prostate cancer.

识别前列腺癌进展的分子和细胞标志物将有助于开发前列腺癌亚分期的诊断方法。为了分离这些基因，我建立了一个大鼠前列腺癌系统。利用大鼠系统，我从8 p21 -22区域分离到了含有转移抑制基因的60-kb片段。这种转移抑制基因似乎没有被翻译成蛋白质。通过使用相同的方法，我已经证明了人类13号染色体含有转移抑制基因。本研究还探讨了人类10号染色体抑制转移的机制。为了从前列腺癌标本中分离出同质的癌组织，我们采用了激光捕获显微切割系统。从显微解剖的组织中提取高质量的DNA并进行遗传分析。比较基因组杂交分析表明，2 q、4 q、6 q、8 p、13 q、16 q和18 q的丢失频率较高。在pT 3肿瘤中观察到8 p和13 q的丢失比pT 2更频繁。Gleason评分≥ 7分的肿瘤中，13 q缺失的发生率更高。6 q缺失与生化复发有关。通过CGH分析鉴定的这些区域与先前通过PCR-LOH分析鉴定的区域基本相同。在本研究中，我还进行了常规的PCR-LOH分析，发现晚期前列腺癌病例中12 p13 - 12、2p16.3、2 p12-cen、2q21.3和2q23.1-32.1位点的丢失频繁。雄激素受体（AR）依赖性途径和AR非依赖性途径。我还进行了临床研究，以便将上述分子数据应用于临床。

Identification of molecular and cellular markers for the progression of prostate cancer would be useful in developing diagnostic methods for substaging prostate cancers. To isolate such genes, I have established a rat prostate cancer system. Clinical specimens have been also examined to identify molecular markers.By using the rat system, I have isolated the 60-kb fragment from 8p21-22 region, which contains the metastasis suppressor gene. This metastasis suppressor gene did not seem to be translated to a protein. By using the same method, I have shown that human chromosome 13 contains metastasis suppressor gene(s). I have also examined the mechanism of metastasis-suppressing function by human chromosome 10.In order to isolate homogeneous cancerous tissue form prostate cancer specimens, laser capture microdissection system was utilized. DNA of high quality was extracted from the microdissected tissue and was genetically analyzed. Comparative genomic hybridization analysis demonstrated that frequent losses of 2q,4q,6q,8p,13q,16q,and 18q. Losses of 8p and 13q were observed more frequently in the pT3 tumors than pT2. A loss of 13q was observed more frequently in the tumors with Gleason score 7 or more. A loss of 6q was related with biochemical recurrence. These regions identified by the CGH analysis were essentially same as those previously identified by the PCR-LOH analysis. In this study, I have also performed the conventional PCR-LOH analysis and have found frequent losses at 12p13-12,2p16.3,2p12-cen,2q21.3,and 2q23.1-32.1 of the cases with advanced cancer.I have reviewed the previous studies on development of hormone-refractory prostate cancer, and found that there are two major pathways, androgen receptor (AR)-dependent pathway and AR-independent pathway. I have also performed clinical studies in order to apply the molecular data above to the bedside.