Rygaard K, Nakamura T, Spang-Thomsen M
University Institute of Pathological Anatomy, Copenhagen, Denmark.
Br J Cancer. 1993 Jan;67(1):37-46. doi: 10.1038/bjc.1993.7.
We examined a panel of 25 small cell lung cancer (SCLC) cell lines and nude mouse xenografts for expression of the proto-oncogenes c-met and c-kit, and for expression of the corresponding ligands, hepatocyte growth factor (HGF) (also known as scatter factor (SF)), and stem cell factor (SCF), respectively. Expression of mRNA was detected by Northern blotting, and c-met and c-kit protein expression was detected by Western blotting and immunocytochemistry. c-met and c-kit mRNA was expressed in 22 of the examined cell lines or xenografts, and coexpression of the two proto-oncogenes was observed in 20 tumours. Expression of c-met and c-kit protein paralleled in the mRNA expression. HGF/SF mRNA was expressed in two of the examined tumours, and only one of these also expressed the c-met proto-oncogene. SCF mRNA was expressed in 19 of the examined tumours, and in 18 of these coexpression of c-kit and SCF was present. The high percentage of SCLC tumours expressing c-met and c-kit indicates that these proto-oncogenes may have an important function in this disease. The rare coexpression of c-met and HGF/SF is evidence that an autocrine regulatory pathway is not present for this receptor/ligand system in SCLC, while the frequent coexpression of c-kit and SCF indicates that this receptor/ligand system may have an autocrine function in SCLC.
我们检测了一组25种小细胞肺癌（SCLC）细胞系及裸鼠异种移植瘤，以分别检测原癌基因c-met和c-kit的表达，以及相应配体肝细胞生长因子（HGF，也称为分散因子（SF））和干细胞因子（SCF）的表达。通过Northern印迹法检测mRNA表达，通过Western印迹法和免疫细胞化学检测c-met和c-kit蛋白表达。在所检测的22种细胞系或异种移植瘤中检测到c-met和c-kit mRNA表达，在20个肿瘤中观察到这两种原癌基因的共表达。c-met和c-kit蛋白表达与mRNA表达情况相似。在所检测的肿瘤中有2个表达HGF/SF mRNA，其中只有1个也表达c-met原癌基因。在所检测的肿瘤中有19个表达SCF mRNA，其中18个同时存在c-kit和SCF的共表达。小细胞肺癌肿瘤中高比例表达c-met和c-kit表明这些原癌基因可能在该疾病中具有重要功能。c-met和HGF/SF罕见的共表达证明小细胞肺癌中该受体/配体系统不存在自分泌调节途径，而c-kit和SCF频繁的共表达表明该受体/配体系统可能在小细胞肺癌中具有自分泌功能。
