NSC74859对食管鳞状细胞癌人源肿瘤异种移植模型的抗肿瘤作用研究

Antitumor effect of NSC74859 on patient-derived tumor xenograft of esophageal squamous cell carcinoma

目的观察小分子抑制剂NSC74859对食管鳞状细胞癌(ESCC)人源肿瘤异种移植模型(patient-derived tumor xenograft,PDX)的抗肿瘤作用及其机制。方法首先利用UALCAN分析信号转导和转录激活因子3(signal transducer and activator of transcription 3,STAT3)在肿瘤及正常样本中的表达。其次将临床手术切除的新鲜的ESCC组织经无菌条件处理后移植到高度免疫缺陷小鼠的皮下,建立ESCC皮下移植肿瘤模型,并将第零代PDX模型(F0)肿瘤组织在裸鼠体内传代至第4代(F4),将F4代ESCC PDX小鼠随机分为两组:NSC74859治疗组,5 mg/kg,每天腹腔注射1次,共给药7 d;溶媒对照组,等体积溶媒注射,每天腹腔注射1次,共给药7 d。每周2次测量裸鼠体重、肿瘤体积,计算相对肿瘤体积和相对肿瘤抑制率,绘制肿瘤生长曲线。观察28 d后脱颈椎处死各组小鼠,摘取肿瘤组织,称量肿瘤湿重。运用Western blot和免疫组织化学方法检测两组瘤体组织中STAT3及p-STAT3蛋白的表达。结果STAT3在多种肿瘤中高表达,在食管癌中表达量最高。ES0172模型在给药开始后第28天时,相对肿瘤抑制率TGI(%)为49.96%(P<0.05);ES0195模型在给药开始后第26天时,相对肿瘤抑制率TGI(%)为53.88%(P<0.05)。ES0172模型和ES0195模型中NSC74859治疗组瘤重都显著低于溶媒对照组瘤重(P<0.05)。p-STAT3在NSC74859治疗组中的表达水平显著低于溶媒对照组(P<0.05)。结论NSC74859能减轻ESCC肿瘤负荷,其抗肿瘤机制可能与下调STAT3的磷酸化水平有关。

Objective To investigate the antitumor effect and mechanism of NSC74859 on Patient-Derived tumor Xenograft(PDX)model of esophageal squamous cell carcinoma(ESCC).Methods Firstly,the expression of signal transduction and activator of transcription 3(STAT3)in tumor and normal samples was analyzed by UALCAN.Secondly,fresh ESCC tissues removed by clinical surgery were transplanted into the subcutaneous of mice with high immunodeficiency after sterile treatment to establish the subcutaneous tumor model of ESCC.Tumor tissues of the zero-generation PDX model(F0)were passed from nude mice to the fourth generation(F4).ESCC PDX mice of the F4 generation were randomly divided into two groups:NSC74859 treatment group,5 mg/kg,intraperitoneally injected once a day for a total of 7 days;in the vehicle control group,constant volume of vehicle was injected intraperitoneally once a day for a total of 7 days.The body weight and tumor volume of the nude mice were measured twice a week,the relative tumor volume and relative tumor inhibition rate were calculated,and the tumor growth curve was plotted.After 28 days of observation,mice in each group were sacrificed after cervical vertebra removal.Tumor tissues were extracted and the wet weight of tumors were weighed.Finally,the protein expression of STAT3 and p-STAT3 in the tumor tissues of the two groups were detected by Western blot and immunohistochemistry(IHC).Results STAT3 was highly expressed in many tumors,with the highest expression in esophageal cancer.The relative tumor inhibition rate(TGI%)of ES0172 model was 49.96%(P<0.05)on the 28th day after administration.The relative tumor inhibition rate(TGI%)of ES0195 model was 53.88%(P<0.05)on the 26th day after administration.Both in ES0172 model and ES0195 model,the tumor weight of treatment group was significantly lower than that of control group(P<0.05).The expression level of p-STAT3 in NSC74859 treatment group was significantly lower than that in vehicle control group(P<0.05).Conclusion NSC74859 can reduce the tumor load of ESCC,and its antitumor mechanism may be related to down-regulating the phosphorylation level of STAT3.