厄洛替尼时辰给药对肺癌模型裸鼠的抑瘤作用及作用机制

Inhibitory effect of chronopharmaceutical drug delivery of erlotinib in lung cancer nude mice model and its mechanism

目的探讨厄洛替尼按时辰给药对肺癌裸鼠模型的抑瘤作用及其可能的作用机制。方法制备HCC827人肺癌细胞皮下移植瘤裸鼠模型,并随机分为6个厄洛替尼组和模型组,每组10只。厄洛替尼组分别在08:00,12:00,16:00,20:00,24:00及次日04:00 ig给予厄洛替尼5 mg·kg-1,模型组给予与厄洛替尼组等体积分数的溶剂磺丁基醚-β-环糊精溶液。测量21 d内裸鼠肿瘤体积变化,处死裸鼠后剥离肿瘤并称量其质量,实时荧光定量PCR和Western蛋白印迹法检测肿瘤组织中表皮生长因子受体(EGFR)及其下游信号转导通路分子丝裂原激活蛋白激酶(MAPK)以及细胞周期蛋白依赖激酶抑制因子1A(P21Waf1)的m RNA和相关蛋白表达水平。结果与模型组比较,厄洛替尼08:00和次日04:00组肿瘤体积显著缩小(P<0.05);厄洛替尼08:00,12:00和次日04:00组肿瘤质量显著降低(P<0.05)。与20:00组〔(0.70±0.36)g〕比较,08:00〔(0.30±0.17)g〕和次日04:00〔(0.39±0.29)g〕组裸鼠肿瘤质量显著降低(P<0.05)。08:00组裸鼠肿瘤组织中EGFR和MAPK的m RNA表达水平显著低于20:00组(P<0.05),而P21Waf1 m RNA表达水平显著高于模型组(P<0.05)。厄洛替尼08:00和次日04:00组p-EGFR和p-MAPK蛋白表达显著低于模型组(P<0.05)。结论厄洛替尼时辰给药对裸鼠移植肺癌的抗肿瘤作用具有时辰节律性,08:00给药组效果最佳,其作用机制可能与EGFR/MAPK/P21Waf1信号转导通路有关。

OBJECTIVE To investigate the pharmacodynamics of chronopharmaceutical drug delivery of erlotinib in lung cancer model nude mice and its potential mechanism. METHODS A nude mouse model of human lung adenocarcinoma HCC827 cell subcutaneously implanted tumor was established and subsequently the nude mice were randomly divided into 6 erlotinib groups and a model group, with 10 nude mouse per group. Erlotinib groups were respectively gavaged with 5 mg.kg-1 erlotinib at 08：00, 12：00, 16：00, 20：00, 24：00 and morrow 04：00, while the model group was given the same volume fraction of captisol. The tumor volume and tumor mass were measured and the tumor growth inhibitory rate was calculated. The mRNA expression of epidermal growth factor receptor （EGFR）, mitogen-acti-vated protein kinase （MAPK）, cyclin-dependent kinase inhibitor 1A（P21Waf1） and the related protein level were detected by real-time quantitative PCR and Western blotting. RESULTS Compared with model group, the tumor volume and tumor mass of mice at the dosing time of 08：00 and morrow 04：00 were significantly decreased（P〈0.05）. Compared with dosing time at 20：00 group〔（0.70±0.36）g〕, the tumor mass of 08：00 group〔（0.30±0.17）g〕 and morrow 04：00〔（0.39±0.29）g〕 group was significantly decreased（P〈0.05）. The mRNA expression of EGFR and MAPK in the tumor group of 08：00 was lower than in group of 20：00（P〈0.05）, while the mRNA expression of P21Waf1 was significantly higher than that of model group（ P 〈0.05）. Compared with model group, the protein expression of p-EGFR and p-MAPK in tumor 08： 00 and morrow 04： 00 group was negative-regulated significantly （P〈0.05）. CONCLUSION The antitumor effect of erlotinib on the human lung adenocarcinoma implanted tumor nude mice model presents rhythmicity. The dosing time at 08：00 is the most effective. lts mechanism is likely related to EGFR/ MAPK/ P21Waf1 signal transduction pathway.