Abstract
Glioblastoma multiforme is the most aggressive primary brain cancer in adults. Therefore, it is important to investigate the mechanisms associated with cell viability and invasion ability of the cells in glioblastoma multiforme. The opposite strand of the glial cell line-derived neurotrophic factor (GDNF) gene is used to transcribe the cis-antisense GDNF opposite strand (GDNFOS) gene, which belongs to the long noncoding RNAs. The current study assessed the effects of GDNFOS1 overexpression and interference on GDNF expression, cell viability and invasion ability in U87 and U251 MG glioblastoma cells. Overexpression and interference were performed using constructed lentiviral vectors, including long non-coding RNA GDNFOS1 overexpression vector, pL-short hairpin RNA (shRNA)-GDNFOS1-9, pL-shRNA-GDNFOS1-49, pL-shRNA-GDNFOS1-248, pL-shRNA-GDNFOS1-9+49, pL-shRNA-GDNFOS1-9+248 and pL-shRNA-GDNFOS1-49+248. Reverse transcription-quantitative PCR was used to determine the efficiency of interference and overexpression of GDNFOS1 in U87 and U251 MG cells. GDNF protein expression in U87 and U251 MG cells was detected using western blot analysis. In addition, cell viability was detected using a cell counting kit-8 assay at 24, 48 and 72 h after GDNFOS1 overexpression or interference. A transwell invasion assay was used to detect invasion ability. Different shRNA sequences were tested and the results revealed that a combination (pL-shRNA-GDNFOS1-49+248) was most effective in the knock-down GDNFOS1. Compared with the control group, GDNF expression in U87 MG cells was significantly increased in the GDNFOS1 overexpression group and decreased in the shRNA-GDNFOS1-248 group. U87 MG cell viability was significantly increased in the GDNFOS1 overexpression group at 24, 48 and 72 h compared with the negative control group. The viability of U87 MG cells was decreased in the GDNFOS1 interference group at 72 h when compared with the control group. The relative invasive ability was significantly increased in the GDNFOS1 overexpression group when compared with the negative control group. The invasive ability was significantly decreased in the GDNFOS1 interference group when compared with the negative control group. Similar results were exhibited by the U251 MG cells. Overall, GDNF expression, cell viability and invasion ability of glioblastoma cells significantly increased with GDNFOS1 overexpression and decreased with GDNFOS1 interference.