Conclusion
autophagy and apoptosis are independent processes of PCD in human ccRCC 786-O cells. Autophagy is the main type of PCD and may be closely associated with apoptosis through the classical death receptor, mitochondria and endoplasmic reticulum apoptosis pathway.
Methods
Atg7-overexpressing and -knockdown RCC 786-O cells (pLenti6.3-ATG7 and sh-ATG7-2 lv) were established using lentiviral transfection and interference shRNA. pLenti6.3-GFP and sh-scramb-con lv were used as controls. Cells were cultured in medium with or without the apoptosis inhibitor Z-VAD-FMK. Cell apoptosis were detected by flow cytometry. Cell proliferation was determined by MTT assay. Expression of apoptotic pathway proteins was measured by Western blot.
Objective
Autophagy plays important roles in tumor occurrence and development. The present study aimed to investigate the association between autophagy and apoptosis in clear cell renal carcinoma cells (ccRCCs).
Results
The apoptosis rate of Z-VAD-FMK-treated cells was significantly decreased compared with untreated cells (P < 0.05). However, no significant difference in the apoptosis rate was detected among cell groups with different autophage level. The Z-VAD-FMK treatment induced significant changes in apoptosis rate in all cell groups, but only slightly changed the cell proliferation. When cell apoptosis were inhibited by Z-VAD-FMK, the cell viability in pLenti6.3-ATG7 group was significantly reduced compared with 786-O control (P < 0.05), whereas the cell viability in sh-ATG7-2 lv was significantly enhanced (P < 0.05) indicating that cell proliferation was closely associated with the level of autophage. The expression of caspase proteins in pLenti6.3-ATG7 was significantly higher compared with sh-ATG7-2 lv group (P < 0.05).