Beta-tubulin - Iii Of The Impact Of High-energy X-ray Irradiation On The Expression Of Lung Adenocarcinoma Cell Line A549

Objective To investigate the effects of high-energy X-ray radiation onβⅢ-tubulin in vitro expression of human lung adenocarcinoma cells.Method A549 human lung adenocarcinoma cells were maintained in RPMI1640 medium and exposed to high-energy X-ray radiation in incremental doses of 0,2,4 and 8 Gy. After exposure, those cells were cultured in the same medium for another 24 or 48 hours. RT-PCR was used to examine the mRNA ofβ-tubulin-Ⅲgene and immunohistochemistry was used to investigateβ-tubulin-Ⅲprotein at the same time.Results The results of F-test showed that there were significant differences in the levels ofβ-tubulin-ⅢmRNA (1) and protein (2) when tested at the same time but different does of radiation (1. F=51.09,49.52, q=4.48～16.83,p<0.05; 2. F=227.81,554.03,q=4.00～52.59, p<0.01 respectively). There were also significant differences at four iradaited doses levels(0,2,4,8Gy) between the 24 hours groups and 48 hours groups (3. t=-3.24～-2.86, p<0.05; 4. t=-11.13～-4.5, p<0.05,0.01).Conclusion The lung adenocarcinoma cells express different levels ofβ-tubulin-ⅢmRNA and protein after exposed to different doses of high-energy X-ray and the levels ofβ-tubulin-Ⅲand protein were different at different time after irradiation.We speculate that the relationship between the level ofβ-tubulin-ⅢmRNA and protein and irradiation is dose-dependent and time-dependent. This maybe part of the mechanism of the tumor drug-resistance after radiotherapy.