Chen J, Liu T, Cui Q
Department of Pathology, Peking Union Medical College Hospital, Beijing.
Zhonghua Bing Li Xue Za Zhi. 1995 Feb;24(1):25-8.
Gene expression of growth factors including epidermal growth factor (EGF), transforming growth factor alpha (TGF alpha), epidermal growth factor receptor (EGFR), oncogenes such as c-myc, N-ras, c-erbB2 and tumor suppressor gene P53 were studied in 4 human lung cancer cell lines using Northern blot technique. Among these cell lines were 2 adenocarcinoma cell lines, one large cell carcinoma cell line and one small cell carcinoma cell line. Expression of EGF and TGF alpha mRNAs were found in all 4 cell lines and EFGR mRNA was seen in 3 out of 4 cell lines. Among these cell lines, 2 cell lines with weaker expression of EGF and TGF alpha, expressed c-myc mRNA. Another 2 cell lines had no c-myc but expressed large amounts of EGF and TGF alpha mRNA. No expression of N-ras, c-erbB2 and p53 were found in these cell lines. The results indicate the presence of autocrine loop of growth factors in these cancer cells. The autostimulation of growth factors may be the main cause for the uncontrolled growth of cancer cells. After treating the cancer cells with EGF, anti-EGF and anti-EGFR antibodies, EGF was found to exert a mild stimulating effect on the growth of one cell line, but no effect on the other cell lines. Anti-EGF and anti-EGFR antibodies inhibited the cell growth on all cell lines. These results provided further evidence for the presence of autocrine loop of growth factors in these lung cancer cell lines.
运用Northern印迹技术，对4种人肺癌细胞系中包括表皮生长因子（EGF）、转化生长因子α（TGFα）、表皮生长因子受体（EGFR）等生长因子的基因表达，以及c-myc、N-ras、c-erbB2等癌基因和肿瘤抑制基因P53进行了研究。这些细胞系中有2种腺癌细胞系、1种大细胞癌细胞系和1种小细胞癌细胞系。在所有4种细胞系中均发现了EGF和TGFα mRNA的表达，4种细胞系中有3种可见EGFR mRNA的表达。在这些细胞系中，2种EGF和TGFα表达较弱的细胞系表达c-myc mRNA。另外2种细胞系无c-myc表达，但表达大量的EGF和TGFα mRNA。在这些细胞系中未发现N-ras、c-erbB2和p53的表达。结果表明这些癌细胞中存在生长因子的自分泌环。生长因子的自刺激可能是癌细胞失控生长的主要原因。在用EGF、抗EGF和抗EGFR抗体处理癌细胞后，发现EGF对一种细胞系的生长有轻微刺激作用，但对其他细胞系无作用。抗EGF和抗EGFR抗体抑制了所有细胞系的细胞生长。这些结果为这些肺癌细胞系中存在生长因子自分泌环提供了进一步的证据。
