Fujita T, Yamaji Y, Sato M, Murao K, Takahara J
First Department of Internal Medicine, Kagawa Medical School, Japan.
Life Sci. 1994;55(23):1797-806. doi: 10.1016/0024-3205(94)90090-6.
Somatostatin (SS) acts as a universal endocrine off-swich, and also inhibits the growth of neuroendocrine tumors through its specific receptors. Small cell lung cancer (SCLC) demonstrates some neuroendocrine characteristics and has been proposed as a candidate for treatment with SS and its analogues. In the present study, we investigated the expression of somatostatin receptor (SSTR) subtype (SSTR1 and SSTR2) mRNA in various human lung cancer cell lines by the sensitive reverse-transcription-PCR method and Southern blotting. The levels of expression of SSTR1 mRNA were higher in both SCLC and squamous cell carcinoma than in adenocarcinoma cell lines. Interestingly, SSTR1 gene expression was independent of that of SSTR2 in each SCLC cell line, although the expression of both genes showed a positive correlation in non-SCLC cells. Membranes from a cell line exhibiting highest expression of SSTR2 gene bound SS and its analogue, octreotide, with moderate affinity. These findings may provide useful information for the future clinical application of SS and its analogues for the treatment of lung cancer.
生长抑素（SS）起着通用内分泌开关的作用，还通过其特异性受体抑制神经内分泌肿瘤的生长。小细胞肺癌（SCLC）表现出一些神经内分泌特征，并已被提议作为用SS及其类似物治疗的候选对象。在本研究中，我们通过灵敏的逆转录 - PCR方法和Southern印迹法研究了生长抑素受体（SSTR）亚型（SSTR1和SSTR2）mRNA在各种人肺癌细胞系中的表达。SSTR1 mRNA的表达水平在SCLC和鳞状细胞癌中均高于腺癌细胞系。有趣的是，在每个SCLC细胞系中，SSTR1基因表达与SSTR2基因表达无关，尽管这两个基因的表达在非SCLC细胞中呈正相关。来自表现出最高SSTR2基因表达的细胞系的膜以中等亲和力结合SS及其类似物奥曲肽。这些发现可能为SS及其类似物未来在肺癌治疗中的临床应用提供有用信息。
