Jetten A M, Vollberg T M, Nervi C, George M D
Cell Biology Section, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
Am Rev Respir Dis. 1990 Dec;142(6 Pt 2):S36-9. doi: 10.1164/ajrccm/142.6_Pt_2.S36.
The lung (in particular the bronchial epithelium) is a major site for tumor formation in humans. Environmental factors in conjunction with genetic factors are important determinants in this disease. The acquisition of defects in the control of proliferation and differentiation appears to constitute crucial steps in the transition of a normal to a neoplastic cell. Several factors have been identified that control positively or negatively the proliferation and differentiation of tracheobronchial epithelial cells. These factors include EGF/TGF alpha, TGF beta, insulin/IGFI, KGF, certain cytokines, retinoids, and activators of protein kinase C. Studies with neoplastic cells have identified several protooncogenes and tumor suppressor genes whose gene products are involved in the regulation of cell growth of normal tracheobronchial epithelial cells, and when mutated, lost, or activated, bring about a neoplastic phenotype. Future studies on the precise function of these genes will help to elucidate the mechanisms by which proliferation and differentiation in normal tracheobronchial epithelial cells are regulated and help to understand the molecular changes involved in diseases such as cancer.
肺（尤其是支气管上皮）是人类肿瘤形成的主要部位。环境因素与遗传因素共同作用是这种疾病的重要决定因素。在增殖和分化控制方面出现缺陷似乎是正常细胞向肿瘤细胞转变的关键步骤。已经确定了几种对气管支气管上皮细胞增殖和分化起正向或负向控制作用的因素。这些因素包括表皮生长因子/转化生长因子α、转化生长因子β、胰岛素/胰岛素样生长因子I、角质形成细胞生长因子、某些细胞因子、类视黄醇以及蛋白激酶C的激活剂。对肿瘤细胞的研究已经确定了几种原癌基因和肿瘤抑制基因，其基因产物参与正常气管支气管上皮细胞的细胞生长调节，当发生突变、缺失或激活时，会导致肿瘤表型。对这些基因精确功能的未来研究将有助于阐明正常气管支气管上皮细胞增殖和分化的调节机制，并有助于理解癌症等疾病所涉及的分子变化。
