肺巨细胞癌高低转移株差异表达基因的鉴定

目的 从两株同源但转移能力不同的人肺巨细胞癌细胞株中分离并鉴定差异表达基因。方法 应用抑制消减杂交(SSH)技术,对来源相间、转移能力不同的人肺巨细胞癌细胞株PLA-801C和PLA-801D进行了两次实验。第1次SSH实验以PLA-801C株为实验方,第2次实验以PLA-801D株为实验方。将获得差异表达的片段点在氨基化的玻片上做成基因芯片,利用荧光标记的探针与芯片杂交,选取差异表达克隆,并利用RNA狭缝杂交或Northern杂交对若干片段进行验证。结果 在低转移肺巨细胞癌细胞株中,高表达的序列有16条;在高转移肺巨细胞癌细胞株中,高表达的序列有79条。测序后经过同源性分析,大部分序列均与已知序列高度间源,主要编码以下几类蛋白：(1)细胞因子及其受体相关蛋白;(2)激酶及其相关蛋白;(3)其他蛋白,包括酶类、热休克蛋白、受体蛋白、细胞骨架蛋白、线粒体蛋白和癌基因编码产物等;(4)一些未知功能的蛋白或是从核酸序列推出来的假想蛋白。结论 HSP70、AXL受体酪氨酸激酶和14-3-3ξ等多种已知基因表达情况的改变,可能影响肺癌的转移过程,此外还发现了一些可能的肿瘤转移相关新基因。

Differentially expressed genes in human giant-cell lung cancer lines with different metastatic potentials

OBJECTIVE: To screen genes differentially expressed in two human giant-cell lung cancer lines of same origin but with different metastasis potentials. METHODS: Suppression subtractive hybridization (SSH) was done twice on two giant-cell lung cancer lines, PLA-801C and PLA-801D (hereafter abbreviated as C and D), of same origin but with low (C) and high (D) metastatic potentials. In the first round, SSH C was used as tester and D as driver, while in the second round, the tester and driver were interchanged. The sequences acquired from both rounds of SSH were spotted on glass slides respectively and screened by hybridizing with two-color fluorescence probes. Clones that had different expression levels on chips were also confirmed by RNA dot blot or Northern blot. RESULTS: There were 16 sequences with high expression in C as compared to those in D, and 79 sequences with high expression in D compared to those in C. After sequencing, most of them were found to be highly homologous to those encoding the following proteins: (1) cytokines and their receptors; (2) kinases and related proteins; (3) other proteins including enzymes, heat shock proteins, receptors, proteins of cell skeleton and mitochondria, products of oncogenes, etc; (4) some proteins deduced from gene sequences with yet unknown functions. CONCLUSION: The alterations in expression of some known genes, including HSP70, AXL receptor tyrosine kinase and 14-3-3zeta, might have impact on metastasis of giant-cell lung cancer. Whether some differentially expressed genes newly revealed are metastasis-related needs further study.