A Role for ch1 in colorectal carcinoma

结肠癌的发展似乎与多种肿瘤抑制基因的失活有关。结肠癌的细胞遗传学和DNA分析检测到染色体1p缺失的频率很高，这表明存在肿瘤抑制基因。因此，我们尝试用含有正常染色体1p34-36的非致瘤性结肠癌细胞和致瘤性逆转细胞分离1号染色体上的抑瘤基因。利用oligo(dT)30-Latex构建非致瘤性结肠癌细胞特异性减法cDNA文库。通过筛选，我们获得了一个克隆（G13），该克隆表达正常染色体1p34-36引入细胞和A9chl，但不表达亲本COKFu和逆转细胞。Northern bolt分析显示G13在正常粘膜中高表达，而在结肠癌中表达减少。接下来，我们对各种人体组织进行northern blot分析，在结肠、小肠、卵巢、睾丸、心脏和胎盘中检测到G13转录本，该基因在进化上是保守的。现在，我们尝试用RACE方法获得全长基因。

Development of colon carcinomas appears to be associated with inactivation of multiple tumor suppressor genes. Cytogenetic and DNA analyses of colon carcinoma have detected a high frequency of chromosome 1p deletion, which suggersts the presence of a tumor suppressor gene. So, we tried the isolation of tumor suppressor gene on chromosome 1 using nontumorigenic colon carcinoma cells containing normal chromosome 1p34-36 and tumorigenic revertantcells.A subtractive cDNA library specific to nontumorigenic colon carcinoma cells was constructed using oligo(dT)30-Latex. As a results of screening, we obtained a clone (G13) which expressed normal chromosome 1p34-36introduced cells and A9chl but not express parental COKFu and revertant cells. Northern bolt analysis revealed that G13 is highly expressed in normal mucosa but reduced in colon carcinomas. Next, we performed northern blot analysis on various human tissues, G13 transcripts were detected in colon, small intestine, ovary, testis, heart, and placenta and the gene evolutionarily conserved. Now, we try the full length gene by the RACE method.