野甘草醇对胸腺激酶依赖的更昔洛韦阻断前列腺癌进展的增效作用

Synergistic effect of scopadulciol in treating human prostate cancer by TK-dependent ganciclovir

目的观察野甘草醇（SDC）在人端粒酶逆转录酶（hTERT）启动子调控腺病毒介导的单纯疱疹病毒胸腺激酶基因／更昔洛韦（HSV—tk／GCV）自杀基因系统对人前列腺癌细胞的杀伤作用中的增效作用。方法测定胸苷激酶（TK）活性，应用高效液相色谱（HPLC）法测定三磷酸更昔洛韦（GCV—TP）在肿瘤细胞内的浓度，将不同配伍浓度的SDC、Ad—hTERT—HSV—tk、更昔洛韦（GCV）应用于前列腺癌细胞，观察体外对前列腺癌细胞的杀伤作用、旁杀伤效应。结果SDC对转染Ad—hTERT—HSV—tk的LNCaP、PC3细胞的TK酶活性影响不明显。应用高效液相色谱法分析，以单加GCV组的GCV—TP浓度计作100％。在加入0．04umolSDC后，GCV—TP浓度与不加SDC比较提高到（101．0±1．5）％，但差异无统计学意义（P〉0．05）；加入5倍治疗剂量0．20umolSDC后，GCV-TP浓度提高到（106．0±4．5）％，差异有统计学意义（P〈0．05）。并进一步通过细胞实验证实，SDC对Ad—bTERT—HSV—tk＋GCV杀伤前列腺癌细胞无明显增效作用，但是旁杀伤效应增加明显。结论SDC对胸腺激酶依赖的GCV阻断前列腺癌进展有一定的增效作用，将天然药物SDC与我们构建的具有肿瘤特异性的重组腺病毒Ad—hTERT—HSV—tk以及GCV联合应用，可以达到增效减毒的目的。

Objective To investigate the synergistic elect of scopadulciol （SDC） on the killing effect on antitumor actions by Ad-hTERT-HSV-tk/ganciclovir （GCV） suicide gene system on prostate cancer cells in vitro. Methods To clarify the mechanism of enhanced effect of SDC in the gene therapy of human prostate cancer by TK-dependent GCV in molecular level, the TK enzyme activity and the concentration of GCV-TP in the tumor cells were measured by using high performance liquid chromatography （HPLC）. The prostate cancer cells, respectively, were treated with Ad-hTERT-HSV-tk or GCV in combination with SDC with different doses and different concentrations. The killing effect and the bystander effect of these drugs in the therapy of human prostate cancer ceils were observed. Results SDC had slightly effect on the TK enzyme activity of LNCaP and PC3 cells that were transduced by Ad-hTERT-HSV-tk. The GCV-TP concentration in the GCV treatment group was 100%. The GCV-TP concentration was （ 101.0 ± 1. 5 ） % when 0. 04 umol/L SDC was added, but there was no significant difference. The GCV-TP concentration was up to （ 106. 0 ±4. 5） % when adding 0. 20 umol/L SDC that was 5-fold higher for the dose of the therapy, and there was significant difference campared to the GCV treatment group （P 〈 0. 05）. It was confirmed that SDC had strong bystander effect and weak killing effect on the prostate cancer cells by conbination of Ad-hTERT-HSV-tk and GCV. Conclusion The synergistic effect of SDC is significantly shown in the therapy of human prostate cancer cells by TK-dependent GCV. SDC is effective in the Ad-hTERT-HSV-tk/GCV administration system in killing prostate cancer cells.