Growth inhibition and mechanisms of human bladder cancer T24 cells by adenovirus-mediated ING4 gene in vitro

Abstract

To explore the inhibitory effect and anti-cancer mechanisms of adenovirus-mediated ING4 gene on the human bladder cancer T24 cells in vitro. The methods of reverse transcription-polymerase chain reaction (RT-PCR) and Western blot were used to detect the expression of ING4 in human bladder urothelial carcinoma T24 line. The influence of Ad-ING4 transfection on cell proliferation was evaluated by MTT assay and cell apoptosis by Hochest33258 staining and flow cytometry. RT-PCR and Western blot were performed to detect the transcriptional level of such apoptosis-related genes as Bcl-2, Bax, p53, HIF-1α and caspase-3. Human ING4 was successfully transcribed in T24 cell. Apoptosis rate of T24 cell in Ad-ING4 group was significant higher than that in control groups (17.2% ± 4.1% vs 4.7% ± 1.2% and 4.8% ± 1.2%, P < 0.05). Ad-ING4 not only up-regulated the expression of p53 and Bax(1.40 ± 0.11 vs 0.27 ± 0.04, 1.50 ± 0.12 vs 0.60 ± 0.05) and down-regulated the expression of Bcl-2 and HIF-1α (0.19 ± 0.02 vs 1.20 ± 0.08, 0.33 ± 0.03 vs 0.98 ± 0.06, all P < 0.05), but also enhanced the caspase-3 activation and eventually led to apoptosis. Adenovirus-mediated ING4 gene exhibits anti-tumor capacity in T24 human bladder cancer cell and induces in vitro apoptosis. It may be related to the up-regulation of P53 and Bax/Bcl-2, and the down-regulation of HIF-1α. Thus the caspase-3 activation is enhanced so as to lead to apoptosis.