朊蛋白在耐阿霉素胃癌细胞系SGC7901/ADR中的过表达及其意义

目的 探讨朊蛋白(PrP)在耐阿霉素胃癌细胞系SGC7901/ADR中过表达及其与胃癌多药耐药性的相关性。方法(1)利用Northern印迹和Western印迹分别从RNA 水平和蛋白质水平检测朊蛋白在胃癌耐药细胞系SGC7901/ADR和SGC7901/VCR及其亲本细胞SGC7901中的表达;(2)借助DNA重组技术构建朊蛋白基因的正反义真核表达载体;(3)通过电穿孔方法将正反义真核表达载体分别转入SGC7901和SGC7901/ADR细胞;(4)以流式细胞仪检测瞬时转染细胞中的阿霉素蓄积和潴留。结果(1)Northern印迹和Western印迹结果提示朊蛋白在SGC7901/ADR和SGC7901/VCR中的表达显著高于其在SGC7901中的表达;(2)将正反义真核表达载体转入SGC7901(命名为PS)和SGC7901/ADR(命名为PA)中,PCDNA3.1空载体转入SGC7901(命名为BS)和SGC7901/ADR(命名为BA);转染48h后检测转染细胞的平均阿霉素荧光强度,阿霉素蓄积BS为8.9±0.7,PS为6.6±0.3,BA为5.5±0.7,PA7.5±0.6,阿霉素潴留BS为8.0±0.7,PS为5.9±0.5,BA5.1±0.7,PA为7.1±0.5,PS与BS相比两组均为P<0.01,BA与BA相比均为P<0.01表达,并对胃癌细胞,具有统计学意义。结论 朊蛋白在胃癌耐药细胞系SGC7901/ADR和SGC7901/VCR中高表达并对胃癌细胞的药物蓄积有影响。

The overexpression of prion protein in drug resistant gastric cancer cell line SGC7901/ADR and its significance

OBJECTIVE: To investigate the overexpression of prion protein (PrP) in drug-resistant gastric cancer cell line SGC7901/ADR and its role in multidrug resistance in gastric cancer. METHODS: (1) The expression of PrP in SGC7901/ADR, SGC790/VCR and their parental cell line SGC7901 was detected with Northern and Western blot at the mRNA and protein level. (2) Eukaryotic sense and antisense expression vector were constructed based on DNA recombination technology and (3) introduced into SGC7901 and SGC7901/ADR cell lines through electroporation. (4) The accumulation and retention of ADR in transiently transfected cells were detected by flow cytometry. RESULTS: (1) Northern and western blot suggested significantly higher expression of PrP in SGC7901/ADR and SGC7901/VCR than that in SGC7901. (2) 48 hours after the vectors transfection, the average fluorescence intensity of Adr in transfected cells were detected. The accumulation intensity were 8.9 +/- 0.7 in BS, 6.6 +/- 0.3 in PS and 7.5 +/- 0.6 in PA. The retention intensity were 9.3 +/- 0.6 in SGC7901, 5.9 +/- 0.5 in PS and 7.1 +/- 0.5 in PA. There were significant difference between PS and BS with P < 0.01, as well as RA and BA with P < 0.01. These data suggested that PrP gene could affect the drug accumulation in gastric cancer cells after its transfected into cells. CONCLUSION: PrP was highly expressed in gastric cancer cell lines SGC7901/ADR and SGC7901/VCR. Overexpression of PrP had certain effect on drug accumulation in gastric cancer cells.