John M, Meyerhof W, Richter D, Waser B, Schaer J C, Scherübl H, Boese-Landgraf J, Neuhaus P, Ziske C, Mölling K, Riecken E O, Reubi J C, Wiedenmann B
Department of Gastroenterology, Benjamin Franklin Medical Centre, Freie Universität Berlin, Germany.
Gut. 1996 Jan;38(1):33-9. doi: 10.1136/gut.38.1.33.
Somatostatin receptor scintigraphy (SRS) is positive in approximately 75% of all patients with neuroendocrine gastroenteropancreatic tumours. This study aimed to identify specific somatostatin receptor (sstr) subtypes, which are responsible for the in vivo binding of the widely used somatostatin analogue, octreotide in human neuroendocrine gastroenteropancreatic tumours. Twelve patients underwent SRS with radiolabelled octreotide. After surgical resection, tumour tissues were analysed in vitro for somatostatin and octreotide binding sites by autoradiography. In addition, for the first time, sstr subtype mRNA expression was examined by semiquantitative reverse transcription polymerase chain reaction (RT-PCR). Tumour tissues from all SRS positive patients were positive by autoradiography. Semiquantitative RT-PCR revealed most prominently sstr2 expression in scintigraphically positive tumours. Two SRS negative tumours contained in vitro octreotide binding sites as well as high levels of sstr1 and sstr2 mRNAs. Positive SRS is mainly due to sstr2. sstr1, 3, 4, and probably 5 are less important for in vivo octreotide binding. False negative scintigraphic results seem to be influenced by factors independent of the expression of specific sstr.
生长抑素受体闪烁扫描术（SRS）在大约75%的神经内分泌胃肠胰腺肿瘤患者中呈阳性。本研究旨在确定特定的生长抑素受体（sstr）亚型，这些亚型负责广泛使用的生长抑素类似物奥曲肽在人类神经内分泌胃肠胰腺肿瘤中的体内结合。12例患者接受了放射性标记奥曲肽的SRS检查。手术切除后，通过放射自显影术在体外分析肿瘤组织中的生长抑素和奥曲肽结合位点。此外，首次通过半定量逆转录聚合酶链反应（RT-PCR）检测sstr亚型mRNA表达。所有SRS阳性患者的肿瘤组织经放射自显影均呈阳性。半定量RT-PCR显示，闪烁扫描阳性肿瘤中sstr2表达最为显著。两个SRS阴性肿瘤含有体外奥曲肽结合位点以及高水平的sstr1和sstr2 mRNA。SRS阳性主要归因于sstr2。sstr1、3、4以及可能的sstr5对体内奥曲肽结合的重要性较低。假阴性闪烁扫描结果似乎受独立于特定sstr表达的因素影响。
