Background and objective: Multidrug resistance (MDR) is the main cause of chemotherapeutic failure in lung cancer, and vinorelbine (NVB) is one of the most efficient drugs that threaten non-small cell lung cancer (NSCLC). The current study aims to establish tumor xenografts and investigate the molecular mechanisms involved in the resistance of NVB in lung adenocarcinoma.
Methods: Nude mice were implanted with Anip973 and Anip973/NVB, and tumor-bearing mice were divided into the Anip973 treatment, Anip973 control, Anip973/NVB treatment, and Anip973/NVB control groups, respectively. The current study observes tumor growth, draws growth curves, and calculates inhibitory rates. The morphological changes in cell tumor were observed through the immunohistochemical method using an electron microscope to detect the expressions of MRP3 and Bcl-2 and to investigate the molecular mechanisms of Anip973/NVB cells.
Results: The tumor inhibitory rates of the Anip973 and Anip973/NVB cells treated with NVB were 60.00% and 4.65%, respectively, compared with the control group. The growth inhibition in the Anip973/NVB cell transplantation tumor had no significant difference. Apoptosis was observed using TEM when the Anip973 transplantation tumor was treated with NVB. On the other hand, no apoptosis was found in the Anip973/NVB transplantation tumor using TEM. Immunohistochemical staining (SP) shows the positive expressions of Bcl-2 and MRP3 proteins in Anip973/NVB transplantation tumor, which were observed to be higher than those in the Anip973 transplantation tumor.
Conclusions: The overexpression of Bcl-2 and MRP3 might be one of the major mechanisms of the MDR of Anip973/NVB.
背景与目的: 肿瘤的多药耐药性（multidrug resistance, MDR）是导致肺癌化疗失败的主要原因，长春瑞滨（Vinorelbine，诺维本，NVB）是治疗非小细胞肺癌最有效的化疗药物之一，本研究旨在建立人肺腺癌Anip973/NVB耐药细胞的动物模型，并初步探讨其耐药机制。
方法: 采用皮下注射法建立人肺腺癌Anip973细胞和耐药细胞Anip973/NVB的裸鼠移植瘤模型，分成Anip973治疗组、Anip973对照组、Anip973/NVB治疗组、Anip973/NVB对照组。观察肿瘤生长情况，绘制生长曲线，计算抑瘤率；通过电镜观察移植瘤的细胞形态学变化；通过免疫组化法检测移植瘤中Bcl-2蛋白和MRP3蛋白的表达来进一步研究人肺腺癌Anip973/NVB细胞的耐药机制。
结果: 与空白对照组比较，Anip973细胞和Anip973/NVB细胞移植瘤经NVB治疗后抑瘤率分别为60.00%、4.65%，Anip973/NVB细胞移植瘤生长受抑无统计学差异；电镜显示：经NVB治疗后，Anip973细胞出现特异性的凋亡形态学特征改变，而Anip973/NVB细胞仍然呈肿瘤细胞生长的典型形态。免疫组织化学染色结果显示：Bcl-2和MRP3蛋白在Anip973/NVB细胞移植瘤中的阳性表达率均明显高于在Anip973细胞移植瘤中的表达（P < 0.001）。
结论: Bcl-2及MRP3蛋白在Anip973/NVB耐药细胞裸鼠移植瘤内的高表达可能是该细胞系耐药的重要机制之一。