Adenovirus-Mediated E2F-1 Gene Transfer Augments Gemcitabine-Induced Apoptosis in Human Colon Cancer Cells
| Autor: | Yun Jiang, Gang Liu, Ziying Lin, Nina Ren, Ya-Peng Shi, Wenya Xu |
|---|---|
| Rok vydání: | 2015 |
| Předmět: |
Cell Survival
Cell Apoptosis DNA Fragmentation Biology Deoxycytidine General Biochemistry Genetics and Molecular Biology Viral vector Adenoviridae Inhibitory Concentration 50 Cell Line Tumor medicine Humans E2F Cell Cycle Gene Transfer Techniques Cell cycle Molecular biology Gemcitabine medicine.anatomical_structure Microscopy Fluorescence Cell culture Cancer cell Colonic Neoplasms Mutation Cancer research Tumor Suppressor Protein p53 E2F1 Transcription Factor medicine.drug |
| Zdroj: | Clinical laboratory. 61(10) |
| ISSN: | 1433-6510 |
| Popis: | Background E2F-1 is a transcription factor that stimulates cellular proliferation and cell cycle progression. E2F-1 alone is sufficient to stimulate cells to initiate DNA synthesis, and this unscheduled entry into S phase is a potent trigger of apoptosis. Gemcitabine, a novel pyrimidine analogue with structural and metabolic similarities to cytarabine, also can efficiently induce apoptosis, especially for cancer cells that are already in S phase. Gemcitabine has established antitumor activity against solid tumors, including head and neck, ovarian, and non-small cell lung cancers. Therefore, we hypothesized that exogenous E2F-1 expression could accumulate cells in the S phase and thus sensitize them to gemcitabine. Methods We constructed an adenoviral vector (AdCMVE2F-1) to transduce the exogenous E2F-1 gene into human cancer cells. Infection of human colon cancer cells with AdCMVE2F-1 resulted in the overexpression of E2F-1 mRNA and protein in a dose-dependent manner and consequently induced accumulation in S phase as measured by FACS analysis. To assess the synergistic antitumor effect of AdCMVE2F-1 and gemcitabine, the human colon cancer cel lines SW620, DLD-1, and LoVo were infected with AdCMVE2F-1 at various multiplicities of infection and then exposed to various concentrations of gemcitabine 24 hours after infection. Result Isobologram analysis showed that E2F-1-transduced cancer cells exhibited higher sensitivity to gemcitabine treatment compared to control virus-infected cells. Treatment with AdCMVE2F-1 plus gemcitabine enhanced endogenous p53 expression in LoVo cells, which contain wild-type p53; however, the finding that the synergistic effect can also be observed in mutant p53-expressing SW620 and DLD-1 cells suggests that wild-type p53 function may not be necessary for the therapeutic effects of this drug combination. Conclusions: Our data demonstrate that overexpression of ectopic E2F-1 protein may render cels more sensitive to gemcitabine-mediated apoptosis, an outcome that has important general implications for the treatment of human cancer. |
| Databáze: | OpenAIRE |
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