The expression and clinical significance of apoptosis stimulating protein of p53 in nonsmall-cell lung cancer

Abstract

Objective To investigate the expression and regulation of ASPP family mRNA in NSCLC cell lines.and study the diagnostic and therapeutic significances of apoptosis stimulating of ps3 expression in NSCLC Patients.Methods Real-time fluorescence quantitative PCR wag established and used to measure the expression Ievels of ASPP mRNA in NSCLC cell lines A549(wild-type p53)and NCI-H157 (mutant-type p53)with p53 different genetic background,and ASPP mRNA was also detected in NSCLC tissue,peripheral blood of 37 NSCLC patients.Western Bloting was used to examine the levels of ASPP1 and ASPP2 proteins of NSCLC cell Iines.Chemosensitivity of the cell lines to CDDP was analyzed by MTT assay,and detect the change of ASPP1 and ASPP2.Compared with the ASPPs mRNA expression between NSCLC patients and healthy controls.and monitoring ASPPs mRNA expression in patients with NSCLC chemotherapy.Results The slope rotes of standard curves were-3.249,-3.358 respectively.and correlation coefficients were more than 0.98.Amplification efficiency of standard curves were 1.156.1.028 respectively.The IC50 values of NCI-H157 and A549 cells were 3.70.10.48 μg/ml respectively.Mean ASPP1 ASPP2 mRNA levels were a statistically significant 2.66 folds and 6.98 folds higher in NCI-H157 cell compared to A549 cell The levels of ASPP1 mRNA in tumor tissues and peripheral blood were (4.27±0.57)×103,(2.49±0.32)×103 in patients with NSCLC respectively,and the levels of ASPP2 mRNA in tumor tissues and peripheral blood were(2.34±0.75)×105,(7.00±1.17)×103 in Patients with NSCLC respectively.The levels of ASPP1 and ASPP2 mRNA in tissues and peripheral blood were(1.32±0.21)×104,(1.46±0.31)×104 and(1.38±0.19)×104,(1.28±0.18)×104 in control groups respectively.The ASPP1,ASPP2 mRNA levels in patients with NSCLC were significantly lower than those of control groups(t=2.58,3.94,3.62,3.76,P＜0.05).Before chemotherapy the levels of ASPP1 and ASPP2 mRNA in patients with NSCLc were(2.34±0.56)×103 and(6.64±0.72)×103,and after 2 periods of postoperative chemotherapy the levels were(3.66±0.64)×103 and(9.42±0.44)×103,the expression was higher than those of ehemotherapy before(t=3.02,4.50,P＜0.05).Conclusions The expression of ASPP1.ASPP2 mRNA in p53 mutant-type cell lines is higher than that in p53 wild-type cell lines.The expression of ASPP maybe has close relationship with chemotherapeutic sensitivity of NSCLC.In NSCLC patient chemotherapy process,the change of ASPP1 and ASPP2 mRNA expression may be related with chemotherapy medicine function.Enhance the expression of ASPP1 and ASPP2 will be beneficial to the tumot treatment. Key words: Apoptosis stimulating protein of p53; Nonsmall-cell lung cancer; Reversed Transcript-Polymanerase Chain Reaction