4-1BBL在不同分化胃癌细胞株上的表达

The expression of 4-1BBL in different gastric cancer cell lines

目的观察共刺激分子4-1BBL在人胃高分化腺癌细胞株MKN-28、人胃中分化腺癌细胞株SGC-7901、人胃低分化腺癌细胞株BGC-823、人胃黏液腺癌细胞株MGC-803上的表达。方法用逆转录-聚合酶链反应（RT—PCR）和免疫细胞化学法检测以上4种胃癌细胞株4-1BBLmRNA和蛋白的表达；噻唑蓝（MTT）比色法检测人淋巴细胞对不同胃癌细胞的体外杀伤活性；酶联免疫吸附试验（ELISA）法检测人淋巴细胞与不同胃癌细胞共培养上清液中白细胞介素（IL）-2、IL-10、肿瘤坏死因子（TNF）-α的含量。结果RT—PCR结果示4-1BBLmRNA表达从高到低依次为MKN-28（46．63％）、SGC-7901（37．13％）、BGC-823（20．43％）、MGC-803（14．14％）。免疫细胞化学结果示4—1BBL着色程度由深到浅依次为MKN-28、SGC-7901、BGC-823、MGC-803。MTT结果示不同时段不同效靶比下人淋巴细胞对胃癌细胞的体外杀伤活性由高到低为MKN-28、SGC-7901、BGC-823、MGC-803。ELISA结果示不同效靶比下人淋巴细胞与胃癌细胞共培养48h上清液中IL-2、TNF-α的含量由高到低为MKN-28、SGC-7901、BGC-823、MGC-803。而IL-10的含量由高到低为MGC-803、BGC-823、SGC-7901、MKN-28。结论人胃癌细胞株MKN-28、SGC-7901、BGC-823、MGC-803中4-1BBL基因在蛋白和mRNA水平均有表达，且胃癌细胞株的分化程度越高4-1BBL表达水平越高。淋巴细胞对高表达4-1BBL胃癌细胞株的杀伤力较高，而且4—1BBL可能通过促进细胞因子TNF—α、IL-2和细胞抑制因子IL一10的产生调节肿瘤免疫。

Objective To study the expression of 4-1BBL and its biological function in different human gastric cancer cell lines. Methods The expression of 4-1BBL in different human gastric cancer cell lines was detected by using immunohistochemistry and reverse transcription-polymerase chain reaction （ RT-PCR ）. The killing activity of lymphocytes against gastric cancer cell lines was measured by MTF, and interleukin （IL）-2, IL-10 and tumor necrosis factor （TNF）-α were determined in the supernatant by enzyme-linked immunosorbent assay （ELISA）. Results The RT-PCR revealed that the 4-1BBL mRNA was expressed in MKN-28 （46. 63% ）, SGC-7901 （37. 13% ）, BGC-823 （20. 43% ） and MGC-803 （ 14. 14% ） in the sequence from high to low levels. The 4-1BBL protein was expressed in MKN-28, SGC-7901, BGC- 823 and MGC-803 in the sequence from high to low levels. MTF analysis indicated that the killing activity was found from high to low in MKN-28, SGC-7901, BGC-823, MGC-803. ELISA analysis showed that IL-2 and TNF-α were found in MKN-28, SGC-7901, BGC-823 and MGC-803, and IL-10 was found in MGC-803, BGC-823, SGC-7901 and MKN-28 from high to low. Conclusion The four different gastric cancer cell lines all express 4-1BBL at the mRNA and protein level. The expression level of 4-1BBL is related to differentiation of gastric cancer cell lines. The killing activity of lymphoeytes against gastric cancer cell lines is increases with the increased 4-1BBL expression. Moreover, 4-1BBL can regulate tumor immunity by promoting the production of TNF-α, IL-2 and IL-10.