丝氨酸/苏氨酸蛋白激酶通路介导的p53基因抑制口腔鳞状细胞癌增殖和侵袭的实验研究

目的 探讨人重组p53腺病毒（rAd-p53）注射液抑制口腔鳞状细胞癌增殖和侵袭的分子机制。方法 采用 rAd-p53注射液转染人舌鳞状细胞癌细胞系Tca8113，观察p53基因过表达对该细胞系增殖及侵袭能力的影响，并用蛋白免疫印迹的方法检测Ad-p53转染前后Tca8113细胞系内丝裂原激活的蛋白激酶（MAPK）、丝氨酸/苏氨酸蛋白激酶（AKT）信号通路相关蛋白，细胞周期及凋亡调控蛋白细胞周期素D1（Cydin D1）、P21、Bcl-2的表达。结果 Ad-p53 转染后显著抑制Tca8113细胞系增殖和侵袭（P<0.01），并促进细胞凋亡（P<0.001）。蛋白免疫印迹结果显示，rAd-p53 转染后显著提高了Tca8113细胞P53和P21蛋白的表达，同时显著下调了Cydin D1、Bcl-2蛋白的表达及AKT蛋白的磷酸化（P<0.01）。结论 AKT信号通路可能是p53引起的口腔鳞癌细胞增殖和侵袭抑制的关键分子机制，Cyclin D1、P21和Bcl-2蛋白可能是AKT信号通路的下游调控基因，AKT信号通路及下游调控基因有望成为肿瘤基因治疗靶点。

The study of serine/threonine kinase signaling pathway-mediated inhibition of proliferation and invasion of oral squamous cell carcinoma transfected with p53 gene

Objective  To evaluate the molecular mechanism of proliferation and invasion inhibition in oral squamous cell carcinoma transfected with recombinant adenovirus-p53 (Ad-p53) . Methods  Tca8113 cell lines were transfected with Ad-p53. Then the effect of p53 overexpression on cancer cells proliferation and invasion was observed. The expression of mitogen -activated protein kinase (MAPK) , serine/threonine kinase (AKT) signaling pathway related proteins, cell cycle and apoptosis related proteins Cyclin D1, P21 and Bcl-2 were detected by Western blotting analysis. Results  After transfected with Ad-p53, the proliferation and invasion of Tca8113 cells were significantly inhibited (P<0.01) and the apoptosis of Tca8113 cells significantly increased (P<0.001). The results of Western blotting demonstrated that the protein expression of P53 and P21 significantly increased, Cyclin D1 and Bcl-2 protein expression and phosphorylation of AKT protein significantly decreased (P<0.01) . Conclusion  The AKT signaling pathway may be a key molecular mechanism for proliferation and invasion inhibition of oral squamous cell carcinoma caused by p53. The protein of Cyclin D1, P21 and Bcl-2 may be the downstream targets of AKT signaling pathway. This may provide a new evidence for AKT pathway and downstream targets as a promising therapeutic target for malignant tumors.