C型凝集素样受体CLEC-2通过PKM2促进非小细胞肺癌吉非替尼耐药的功能机制研究

The occurrence of drug resistance on lung cancer is the most important factor in failure of molecular therapy. Continuous gefitinib treatment beyond progression has shown promising benefit for some patients but with acquired resistance to gefitinib. Unfortunately, there is no effective way to the reversion of drug-resistant currently. Study found that the molecular mechanism of drug-resistant on tumor cells is very complex. In addition to the reduction of drug concentration in the tumor cells, the target gene mutation, amplification, acceleration of DNA break repair, alteration of apoptosis genes expression all contribute to the occurrence of drug-resistance the cells. CLEC-2 is an important pattern recognition receptor, which meditates physiologic processes including siganalling transduction, immune response, inflammation reaction and cell migration. Recently, our preliminary lab study found that CLEC-2 can sensitize tumor cells to migration, and CLEC-2 is closely linked to the tolerance of drug on tumor in human. This project has shown that CLEC-2 expression level in lung cancer is significantly higher than that in normal lung tissue, suggesting that CLEC-2 may be involved in drug-resistance on human non-small cell lung cancer. By using quantitative real time PCR technology, CCK8 assay, flow cytometry, we investigated the relationship between CLEC-2 and apoptosis-related gene expression, apoptosis and the drug-resistant lung cancer cells. Moreover, we found CLEC-2 interacts with Warburg effect kinase PKM2 and regulate the expression of PKM2, which leads to gefitinib-resistance in non-small cell lung cancer. The goal of our study is to find a new way which might be helpful for the reversion of gefitinib-resistance in non-small cell lung cancer and could enhance the effects of molecular targeted therapy for the NSCLC. At the same time, we anticipate that CLEC-2 might be a new target for the treatment of lung cancer.

肿瘤细胞耐药是导致非小细胞肺癌（NSCLC）分子靶向治疗失败的主要原因，研究发现肿瘤细胞耐药的分子机制很复杂，除了药物进入肿瘤细胞内浓度减少外，靶基因突变、细胞抗/促凋亡基因表达差异等都会导致肿瘤细胞耐药，对NSCLC耐药分子机制的进一步探讨和逆转肺癌耐药方法的研究已成为当今科研热点。CLEC-2是一类重要的抗原分子模式识别受体，参与信号传导、免疫应答、炎症反应以及细胞迁移等重要生理学过程。我们前期工作发现CLEC-2高表达NSCLC细胞及组织上，并通过免疫组化分析及肿瘤生物学行为实验证实CLEC-2表达与人NSCLC发展密切相关，此外，我们还通过质谱组学方法发现CLEC-2与Warburg效应激酶PKM2相互作用，进一步研究发现PKM2影响CLEC-2介导的NSCLC吉非替尼抵抗。本项目拟通过体深入探究CLEC-2促进NSCLC吉非替尼耐药的作用及机制来寻找解决吉非替尼疗效耐受的新途径。

糖链是细胞表面普遍的一种修饰结构，细胞表面糖链的异常与肿瘤发展密切相关，而糖链的细胞通讯作用依赖于其和凝集素相互作用。C型凝集素是一类重要的抗原分子模式识别受体，参与机体信号传导、免疫应答、炎症反应以及细胞迁移等重要生理学过程。我们研究发现C型凝集素CLEC-2在肺癌中表达上调，并通过结合丙酮酸酸激酶PKM2介导肺癌细胞gefitinib抵抗，同时，我们探究C型凝集素CLEC-2的糖配体通过CLEC-2抑制胃癌细胞TGF-β1分泌以及胃癌细胞恶性表型转化的机制。此外，我们还发现C型凝集素LOX-1通过激活PI3K/Akt/GSK3β信号通路促进胃癌细胞迁移侵袭能力，促进胰腺癌细胞IL-6分泌表达上调以及上皮间质转化来影响肿瘤细胞生物学行为。该项目研究阐明了C型凝集素在肿瘤中异常表达导致肿瘤细胞上皮间质转化以及肿瘤耐药的机理，为凝集素在肿瘤生物学功能方面的研究提供了新视角，并推进我们对凝集素与肿瘤发展关联的深入理解，也为靶向凝集素的药物研究奠定了重要的分子生物学基础。