Veillette A, Foss F M, Sausville E A, Bolen J B, Rosen N
Medical Breast Cancer Section, National Cancer Institute, Bethesda, Maryland 20892.
Oncogene Res. 1987 Sep-Oct;1(4):357-74.
The tyrosine kinase p56lck is felt to be expressed solely in cells and tissues of lymphoid lineage. We have observed in the particulate fractions of colon carcinoma cells the presence of a 56 kilodalton (kD) alkali resistant phosphoprotein containing phosphotyrosine. Further analysis revealed that the partial proteolytic cleavage pattern of this protein is analogous to that of the lck gene product found in murine and human T-cells. We have confirmed by cDNA cloning that lck RNA is also expressed in these cells proportionally to the amount of p56lck found in membrane preparations. Additional analysis demonstrated that lck RNA is frequently expressed in certain non-lymphoid tumor cell lines such as cell lines derived from colon carcinomas and carcinomas of the lung. Interestingly, higher levels of lck expression were found in human tumor cell lines derived from metastatic tumor sites when compared to those derived from primary tumors. These observations raise the possibility that the lck gene product may be involved in progression of some non-lymphoid human tumors.
酪氨酸激酶p56lck被认为仅在淋巴谱系的细胞和组织中表达。我们在结肠癌细胞的颗粒部分观察到一种含有磷酸酪氨酸的56千道尔顿（kD）耐碱磷蛋白的存在。进一步分析表明，这种蛋白质的部分蛋白水解切割模式类似于在小鼠和人类T细胞中发现的lck基因产物。我们通过cDNA克隆证实，lck RNA在这些细胞中的表达也与膜制剂中发现的p56lck量成比例。额外的分析表明，lck RNA在某些非淋巴细胞肿瘤细胞系中经常表达，如源自结肠癌和肺癌的细胞系。有趣的是，与源自原发性肿瘤的细胞系相比，在源自转移瘤部位的人类肿瘤细胞系中发现了更高水平的lck表达。这些观察结果增加了lck基因产物可能参与某些非淋巴细胞性人类肿瘤进展的可能性。
