It has been reported that metastasis-associated gene 1 (Mta1) is overexpressed in many malignant tumors with high metastatic potential. In addition, some studies indicated that MTA1 participated in invasion, metastasis, and survival of cancer cells by regulating cell migration, adhesion and proliferation. But the role of MTA1 is unclear in vitro in the development of cervical cancer cells. This study investigated whether and how MTA1 mediated cell proliferation, migration, invasion and adhesion in cervical cancer. MTA1 expression level was detected by Western blot in two cervical cancer cell lines of different invasion potentials. The effects of MTA1 expression on SiHa cell apoptosis, cycle, proliferation, migration, invasion and adhesion were tested by flow cytometry, MTT, wound-healing assay, Transwell assay and adhesion assay, respectively. The expression levels of p53, E-cadherin, and β-catenin activity were evaluated in untreated and treated cells. The results showed that MTA1 protein expression was significantly higher in SiHa than in HeLa, which was correlated well with the potential of migration and invasion in both cell lines. Furthermore, the cell invasion, migration and adhesion capabilities were decreased after inhibition of MTA1 expression mediated by Mta1-siRNA transfection in SiHa. However, no significant differences were found in cell apoptosis, cycle, and proliferation. In addition, E-cadherin and p53 protein levels were significantly up-regulated, while β-catenin was significantly down-regulated in SiHa transfected with the siRNA. These results demonstrated that MTA1 played an important role in the migration and invasion of cervical cancer cells. It was speculated that the decreased migration and invasion capability by inhibiting the MTA1 expression in the SiHa cell line may be mediated through the altered expression of p53, and E-cadherin/β-catenin complex. MTA1 could serve as a potential therapeutic target in cervical cancer.
目的以柯萨奇-腺病毒受体(Coxsackie and adenovirus receptor,CAR)蛋白结构的功能解析作为切入点,构建不同CAR胞内域缺失突变的表达载体。方法利用定点缺失突变策略构建CAR胞内域PKC、CK2、TYR磷酸化位点的缺失突变体及胞内域完全缺失的突变体。利用三步PCR法扩增获得相关的基因片段后,将其克隆入真核表达载体pcDNA3.1/V5/His,通过双酶切及测序进行鉴定后,分别转染至低表达CAR的人卵巢癌细胞系SKOV3细胞中,并用Werstern blot检测细胞转染后CAR的表达水平。结果所有突变体经过测序分析均证实序列与设想的突变序列相符,各突变体在SKOV3细胞中获得了满意的表达。结论成功构建不同CAR胞内功能域缺失突变表达载体,为后续研究CAR及其胞内不同功能域在卵巢癌中的作用机制提供了研究基础。
柯萨奇-腺病毒受体(Coxsackie and adenovirus receptor,CAR)最早作为2型和5型腺病毒的受体而被人们发现和认识。大量研究发现CAR可以影响肿瘤细胞的生长、细胞骨架的变化、细胞间的粘附等,从而在肿瘤侵袭转移过程中起非常重要的作用。而且,CAR的表达与肿瘤的预后和腺病毒介导的减瘤效应也有密切的关系。基于CAR的重要作用,CAR已逐渐成为肿瘤发生发展机制及治疗领域研究中新的"热点",本文结合CAR的基本结构及功能对以上研究的进展作一综述。
