Development of Systems for Comprehensive Genetic Diagnosis of Human Cancers and for Early Detection of Cancer-patients.

1996年，我们在遗传不稳定（MI+）结直肠癌的一个子集中发现了编码E2 F4转录调节因子的基因中的一种新的肿瘤特异性突变。发现该突变是DNA错配修复基因hMSH 3基因失活移码突变的结果。因此，E2 F4基因首次被鉴定为涉及hMSH 3蛋白的缺陷性错配修复功能的靶标。这一观点已得到许多支持性论文的证实。与此相关的是，我们在弥漫性大B细胞淋巴瘤细胞系中发现了人p107基因（肿瘤抑制基因RB的近亲）内的间质缺失。我们发现缺失是由两个包含约15 kbp的重复序列之间的重组引起的。通过我们的基因组扫描方法，我们在约30%的肾细胞癌中发现了染色体14 q24 -31的一个新的杂合性缺失（洛）区域，并在这个狭窄区域中鉴定了两个候选肿瘤抑制基因（TSG）。 ...更多信息 吉翁。通过常规微卫星分析，我们发现在人类头颈部肿瘤中染色体13 q34处的洛缺失发生率很高。已知的候选TSG，ING 1，位于该研究中心。本研究阐明了ING 1基因的全基因组结构，并在3例原发性头颈部肿瘤中发现了3个13 q34洛缺失的失活点突变，首次证明p107和ING 1基因具有TSG的功能，同时发现了一个新的蛋白酪氨酸磷酸酶基因HD-PTP作为TSG的候选基因。该基因位于染色体3p21.3，该区域被认为包含许多类型人类癌症的多个TSG。通过类似的方法，我们在7个癌症/肿瘤组的8个染色体区域中发现了至少10个TSG候选者。除TSG外，我们还分离到一个编码新POZ锌指蛋白的cDNA，该蛋白的表达导致受体细胞恶性表型，表明该基因是一个新的癌基因。该基因定位于3q 26 -27，与已知的癌基因Bcl-6相关。在肿瘤的分子诊断方面，我们报道了一种系统的检测骨/软组织肉瘤中肿瘤特异性融合基因mRNA的方法。我们已经开发了一种新的策略来定量血清/血浆中游离DNA的量，具有非常高的灵敏度（比常规方法高约一万倍）。在这些血清DNA中可以检测到癌症特异性的基因改变，如K-ras和p53突变，因此，利用血浆/血清中的游离DNA开发了用于早期检测潜在癌症患者的有希望的策略。少

We have found a novel tumor-specific mutation in the gene encoding E2F4 transcription regulator in a subset of genetically unstable (MI+) colorectal cancers in 1996. The mutation was found to be a result of the inactivating frame-shift mutation of the hMSH3 gene, a DNA mismatch-repair gene. Thus, the E2F4 gene was identified, for the first time, as a target of the defective mismatch repair function involving hMSH3 protein. This notion has been confirmed bv many supporting papers. Relevant to this result, we have found an interstitial deletion within the human p107 gene, a close relative of the tumor suppressor gene RB, in a diffuse-large B cell lymphoma cell line. We found the deletion was raised by a recombination between two Alu-repeats encompassing about 15 kbp. By our genomic scanning method, we found a novel region of loss of heterozygosity (LOH) at chromosome 14q24-31 in about 30% of renal cell carcinomas and identified two candidate tumor suppressor genes (TSG) in this narrow re … More gion. By conventional microsatellite analysis, we found a high incidence of LOH at chromosome 13q34 in human head and neck cancers. The known candidate TSG, ING1, resides at this site. We clarified the whole genomic structure of the ING1 gene and found 3 inactivating point mutations in 3 primary head and neck cancers with 13q34 LOH.These are the first evidence indicatins that the p107 and ING1 genes function as TSG.Further, we discovered a novel protein tyrosine-phosphatase gene, HD-PTP, as a novel TSG candidate. The gene resides at chromosome 3p21.3, the region thought to contain multiple TSG for many types of human cancer. By similar approaches we found at least 10 TSG candidates at 8 chromosomal regions in 7 cancer/tumor groups. In addition to TSG, we isolated a cDNA encoding a novel POZ-Zn-Finger protein, whose expression led the recipient cells to malignant phenotype, suggesting that the gene is a novel oncogene. The gene locates on 3q26-27 and related to the known oncogene, Bcl-6.As to the molecular diagnosis of cancer, we reported a systematic method for detecting tumor-specific, fused-gene mRNAs in several bone/soft-tissue sarcomas. We have developed a new strategy to quantitate the amounts of free DNA in sera/plasma with a very high sensitivity (about ten thousand-fold higher than conventional methods). Cancer-specific genetic alterations, like as K-ras and p53 mutations, could be detected in these serum-DNA.Thus, promising strategies for early detection of potential cancer-patients were developed with free DNA in plasma/serum. Less