Effect of Δ40p53 isoform on enhancing the pro-apoptotic function of p53 in tumor cells
10.3760/cma.j.issn.0253-3766.2017.05.003
- VernacularTitle: Δ40p53对p53促肿瘤细胞凋亡作用的影响
- Author:
Bishi WANG
1
;
Hongwei ZHAO
2
;
Luxin QIAO
3
;
Junqi SHAN
1
;
Qingsheng HOU
1
;
Dexi CHEN
3
;
Hongliang GUO
1
Author Information
1. Department of General Surgery, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Cancer Hospital and Institute, Jinan 250117, China
2. Department of Medical Records Management, Shandong Cancer Hospital Affiliated to Shandong University, Shandong Cancer Hospital and Institute, Jinan 250117, China
3. Beijing Institute of Hepatology, Beijing You′ an Hospital, Capital Medical University, Beijing 100069, China
- Publication Type:Journal Article
- Keywords:
Neoplasms;
p53;
Δ40p53;
Apoptosis
- From:
Chinese Journal of Oncology
2017;39(5):332-338
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the effect of Δ40p53, an alternative spliced isoform of p53 lacking the N-ter minus, on the pro-apoptotic function of p53.
Methods:The wild-type p53 was ectopically expressed in HCT116-p53-/- (endogenous Δ40p53 expression), HCT116-p53+ /+ (wild-type p53) and H1299 (p53-null) cells by adenoviral delivery, while Δ40p53 plasmid were transfected into these cells to overexpress Δ40p53. The levels of Δ40p53 and p53 mRNA were detected by reverse transcription-polymerase chain reaction (RT-PCR) and quantitative PCR. The expression of related proteins was deter mined by Western blotting. The interaction of p53 and Δ40p53 was observed by co-immunoprecipitation assay. Calcein-AM/propidium iodide (PI) staining and flow cytometry were used to detect the apoptotic rate of tested cells in each group.
Results:HCT116-p53-/- cells expressed endogenous Δ40p53 isoform. Neither transcription nor protein expression of wild-type p53 was interfered by the increased expression of Δ40p53. Full length p53 and Δ40p53 could bind to each other. Calcein-AM/PI staining showed that the apoptotic rates of H1299-Control, HCT116-p53-/- -Control, H1299+ p53, HCT116-p53-/-+ p53, H1299+ oxaliplatin (Oxa), HCT116-p53-/-+ Oxa, H1299+ p53+ Oxa and HCT116-p53-/-+ p53+ Oxa groups were (2.50±0.47)%, (2.40±0.32)%, (5.20±0.58)%, (4.10±0.18)%, (22.40±1.73)%, (19.30±1.11)%, (29.90±1.15)% and (39.30±2.26)%, respectively. It was statistically significant between H1299+ p53+ Oxa and HCT116-p53-/-+ p53+ Oxa groups (t=3.721, P=0.0205). Moreover, the apoptotic rates of H1299-Control, H1299+ Δ40p53, H1299+ p53, H1299+ p53+ Δ40p53, H1299+ Oxa, H1299+ Δ40p53+ Oxa, H1299+ p53+ Oxa and H1299+ p53+ Δ40p53+ Oxa groups were (2.60±0.35)%, (2.20±0.17)%, (4.80±0.49)%, (4.90±1.10)%, (20.30±1.10)%, (19.60±1.45)%, (27.90±1.39)%, (35.20±1.43)%, respectively. Furthermore, flow cytometry assay showed that the apoptotic rates of above cells were (2.70±0.32)%, (2.20±0.24)%, (4.60±0.48)%, (3.90±0.67)%, (19.30±1.11)%, (17.70±0.66)%, (28.30±2.76)% and (37.50±1.51)%, respectively. H1299+ p53+ Δ40p53+ Oxa cells showed higher cell apoptosis than H1299+ p53+ Oxa cells (t=2.930, P=0.042).
Conclusion:Δ40p53 isoform can bind to full-length p53, and enhance its pro-apoptotic function in tumor cells.
