基于PI3K/AKT/mTOR和ERK/MAPK双信号通路探讨PAP-2抗肺癌机制研究

Lung cancer is one of the most common and fatal cancers in the world. The incidence and mortality of lung cancer in China has increased because of smoking and increased air pollution with the constant promotion of industrialization and urbanization. Currently, the treatment effect of lung cancer is poor and the long-term chemotherapy can damage the vital organs and cause drug resistance. Therefore, the research and development of more effective and less toxic antitumor drugs from natural sources is necessary. Based on the study of lung cancer occurrence, metastasis and related gene expression, an anti-cancer peptide PAP-2 with a molecular weight of 1080 Da was obtained from Perineries aibuhitensis by enzymolysis and purification strategies. In vitro and in vivo studies also showed it has significant effects on apoptosis and gene regulation of lung cancer cells. In this study, PAP-2 will be used to lung cancer cells H1299 to elucidate its drug targets and anti-lung cancer mechanisms on the basis of PI3K/AKT/mTOR and ERK/MAPK pathway. H1299 nude-mouse transplanted tumor model will also be established to explore the effects of PAP-2 and its anti-lung cancer mechanism in vivo .The program lays the foundation for the development of a research and development with independent intellectual property rights of marine peptide drugs against lung cancer. Therefore, it has important academic values and good application prospect.

肺癌是全球发病率最高的恶性肿瘤，已成为肿瘤相关死亡的首要病因。随着国家工业化、城镇化推进，导致雾霾日益加重，肺癌在我国成为全球重灾区。目前肺癌的治疗效果较差，长期化疗损害重要脏器且会产生耐药。因此，寻找低毒、高效新型抗癌药物势在必行。项目申请人在研究肺癌发生、转移及相关基因表达基础上，从双齿围沙蚕中筛选得到分子量为1080 Da、化学结构明确的活性多肽PAP-2，经前期体内外研究有显著诱导肺癌胞凋亡和基因调控作用。现将PAP-2作用于肺癌细胞株H1299，基于PI3K/AKT/mTOR和ERK/MAPK双信号通路，明确其药物靶点；研究PAP-2体内对肺癌H1299裸鼠移植瘤模型的药效学实验，探讨PAP-2抗肺癌机制，阐明其抗肺癌效果和相关基因表达。本研究为研发一种具有自主知识产权的抗肺癌海洋肽类药物的研发奠定基础。因此，具有重要的学术价值和良好的应用前景。

肺癌是全球发病率最高的恶性肿瘤，已成为肿瘤相关死亡的首要病因。目前肺癌的治疗效果较差，长期化疗损害重要脏器且会产生耐药。因此，从天然资源中寻找低毒、高效新型抗癌药物势在必行。项目组从双齿围沙蚕中筛选获得抗肺癌活性多肽PAP，氨基酸序列为Ile-Glu-Pro-Gly-Thr-Val-Gly-Met-Met-Phe，分子量为1080 Da。PAP对肺癌H1299细胞表现出明显的增殖抑制活性，并且呈现明显的剂量依赖性，与正常对照组相比，肺癌H1299细胞的早期凋亡率上升、线粒体膜电位下降，使H1299细胞阻滞在G2/M。PAP诱导H1299细胞凋亡，可能是通过下调抗凋亡基因Bcl-2蛋白表达，上调促凋亡基因Bax，激活p53基因，下调VEGF-单体、VEGF-二聚体表达，活化了的胱天蛋白酶Caspase-9蛋白，活化的Caspase-9激活下游的效应Caspase-3，并下调nm23-H1表达，减少转移，引发凋亡级联效应而实现的；PAP对肺癌细胞移植瘤有一定的抑制作用，PAP作用后其血液中的VEGF含量下降，肿瘤组织中Bax蛋白含量增加，Bcl-2蛋白含量减少，推测通过Bax/Bcl-2的比率来调控线粒体膜电位的变化，从而启动内源性凋亡的通路；活化p53蛋白，下调VEGF蛋白从而引起细胞凋亡，导致移植瘤变小。此外，本项目研究发现PI3K/AKT/mTOR是沙蚕蛋白酶NAP诱导H1299细胞凋亡的潜在信号通路机制之一。本项目研究为开发一种具有自主知识产权的抗肺癌海洋肽类药物奠定基础，具有重要的学术价值和良好的应用前景。