gsp癌基因在人垂体生长激素腺瘤的表达及与GHRH对生长激素分泌效应比较

Expression of gsp Oncogenes in Human Somatotrophinomas and Their Correlation with Effects of GHRH on Growth Hormone Secretion

采用聚合酶链反应和直接序列分析法评价了30例肢端肥大症肿瘤组织的gsp癌基因,发现9例30％为gsp癌基因阳性。结果与生长激素释放激素对生长激素分泌效应比较,发现gsp癌基因阳性和阴性肿瘤体外生化特征各自差异较大,推测可能与细胞间多信号传导系统介入有关。

A subgroup of growth hormone (GH)-secreting pituitary adenomas carried somatic point-mu- tations within the gene coding for a subunit of the stimulatory heterotrimetic GTP-binding protein, G,α. These so-called gsp oncogenes were proposed to play an important role in the development of human pituitary adenomas. We used in vitro cell culture to compare the stimulatory effects of GH-releasing hormone (GHRH) on the GH secretion of somatotrophinomas examined, 9 (30%) proved to be gsp positive, as deter- mined by direct sequencing analysis of DNA generated by the polymerase chain reaction (PCR). The results showed highly variable effects of GHRH on GH secretion of both types of somatotrophinomas. This suggests the complex control of GH secretion via multiple signal transduction pathways at the cellular level.