Genetic alterations within the retinoblastoma locus in colorectal carcinomas. Relation to DNA ploidy pattern studied by flow cytometric analysis.
Genetic alterations within the retinoblastoma locus in colorectal carcinomas. Relation to DNA ploidy pattern studied by flow cytometric analysis.
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DOI：
10.1038/bjc.1991.334
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发表时间：
1991-09
影响因子：
8.8
通讯作者：
Rognum, T O
中科院分区：
文献类型：
--
作者：
Meling, G I;Lothe, R A;Borresen, A L;Hauge, S;Graue, C;Clausen, O P;Rognum, T O
用VNTR探针p68RS2.0检测255例结直肠癌中Rb基因的改变，并结合流式细胞术DNA分析。总共有35.3%的肿瘤在Rb基因内发生了改变。29.5%的肿瘤表现为一个等位基因扩增，11.5%的肿瘤表现为杂合性缺失。未发现Rb基因扩增与患者的临床病理特征之间存在关联。Rb基因内的高频率的改变表明，该基因与结直肠癌的发生有关，扩增是迄今为止最丰富的遗传改变。这可能意味着Rb基因在结直肠癌中具有癌基因样功能，而不是作为肿瘤抑制基因。63%的肿瘤为DNA异倍体，Rb基因扩增与DNA异倍体之间存在显著相关性（P <0.01）。另外两个染色体基因座分别在染色体1p（探针pYNZ 2）和染色体2p（探针pYNH 24）上进行了分析。在染色体1p上，在22.2%的肿瘤中发现杂合丢失，表明该染色体参与了结肠直肠癌的一个子集。
Alterations within the retinoblastoma (Rb) gene, as detected by the VNTR probe p68RS2.0, and flow cytometric DNA pattern have been analysed in 255 colorectal carcinomas. A total of 35.3% of the tumours had alterations within the Rb gene. Amplification of one allele was demonstrated in 29.5% of the tumours, and loss of heterozygosity was found in 11.5%. No association was found between amplification within the Rb gene and clinicopathological characteristics of the patients. The high frequency of alterations demonstrated within the Rb gene, suggests that this gene is involved in colorectal carcinogenesis with amplification as by far the most abundant genetic alteration. This may imply that the Rb gene has an oncogene-like function in colorectal carcinomas, rather than acting as a tumour suppressor gene. Sixty-three per cent of the carcinomas were DNA aneuploid, and a significant association was demonstrated between amplification within the Rb gene and DNA aneuploidy (P less than 0.01). Two other chromosome loci were analysed, on chromosome 1p (probe pYNZ2) and on chromosome 2p (probe pYNH24), respectively. On chromosome 1p, heterozygous loss was found in 22.2% of the tumours, indicating an involvement of this chromosome in a subset of colorectal carcinomas.