胸苷酸合成酶、胸苷酸磷酸化酶的表达与培美曲塞时辰化疗的疗效分析

目的构建肺腺癌A549细胞的裸鼠皮下移植瘤模型，研究按昼夜不同时辰给予培美曲塞是否能提高疗效和降低不良反应，分析胸苷酸合成酶（TS）mRNA和胸苷酸磷酸化酶（TP）mRNA表达高低与培美曲塞疗效以及不良反应的关系。方法 常规方法体外培养肺腺癌A549细胞。待肿瘤体积生长至0.5~1.5 cm³，随机将荷瘤鼠分为四组，每组5只，其中三组严格按照每昼夜24 h的三个时间点给药即:早晨7点（光照后0 h）、中午15点（光照后8 h）、晚间23点（光照后16 h）进行腹腔给药，第四组为对照组，腹腔给予同体积的0.9%氯化钠溶液。培美曲塞按照150 mg/kg应用，每天一次，连续4天。以后每周测量瘤体积，裸鼠体重，观察裸鼠的行为状态、精神以及食欲变化。实验结束时称量剥离的裸瘤重量。应用实时荧光定量PCR（Real-Time PCR）检测肿瘤组织中TS mRNA和TPmRNA的表达水平。结果7 h给药组裸鼠体重增长较快（P=0.041），化疗不良反应较小，瘤体积生长最慢（P=0.032），抑瘤率最大（P=0.000）。7 h给药组的肿瘤组织中TS mRNA相对表达量最低，TP mRNA的相对表达量对高，差异有统计学意义（P<0.01）。结论培美曲塞对肺腺癌裸鼠移植瘤有明显的抑制作用，疗效及不良反应与时辰给药有关，7 h给药组疗效最佳，化疗不良反应最小;TS和TP可以作为培美曲塞的疗效预测因子，为培美曲塞的个体化临床用药提供参考。

TS mRNA and TP mRNA of Transplantation Lung Adenocarcinoma Tumor in Nude Mice and Pemetrexed Chrono-chemotherapy for Therapeutic Effect Analysis

Objective
To evaluate if pemetrexed disodium was given to the nude mice bearing lung adenocarcinoma cell line A549 cells at
different times in the day and night according to the theory of chronopharmacology can enhance the curative
effect and reduce side-effects.Methods1×10⁷ A549 cells in exponential phase of growth were vaccinated in the
good health body of Balb/c nude mice by subcutaneous injection(injection under the skin).When tumor volume
reached 0.5~1.5 cm3，tumor-burdened nude mice was divided randomly into four groups and each group has 5 mice，
Three groups were randomly appointed to 7 hour group，15 hour group and 23 hour group according to the three time
of injection of 07:00， 15:00，23:00， for abdominal administration.The remainder group was left for blank
controlled group，for abdominal the same volume of saline.The tumor tissue was measured from major axis to
minimum width once a week,and calculated the volume for drawing the growth curve.As the tumor,tissue growing to
meet the volume of 0.5~1.5cm³,intraperritoneal injection with pemetrexed disodium was performed at 150 mg/kg
(total dose，600 mg) in 200 μl PBS i.p.for 4 consecutive days (days 0~3).Meanwhile,The observiation was carried
out as the following:the appetite,the movement,and the mental state of nude mouse,as well as the tumor size.The
weight of the nude mice was measured once a week for drawing the chart.The tumor weight of the nude mice was
calculated for counting the tumor inhibition rate.qRT-PCR was applied to detect the expression of the TS mRNA and
TP mRNA in the tumor tissue.Results Pemetrexed for lung adenocarcinoma nude mice transplant tumor has good
curative effect，7 h group tumour inhibition rate was the highest（P=0.000），the slowest tumor growth（P=0.032）
，the more nude mice weight（P=0.041）relative express level of TS mRNA of 7 h group tumor tissue was the lowest
，however，TP mRNA was the highest.Difference was statistically significant（P<0.05）.ConclusionPemetrexed for
lung adenocarcinoma nude mice transplant tumor has apparent inhibition and efficacy and side effects appears hour
rhythm changes，the curative effect of 7 h group was the best.it looks on TS mRNA and TPmRNA as side effects and
curative effect biological marker of pemetrexed，it provideds us reference for rationalization and individualized
clinical application of pemetrexed.