基于质谱的药物蛋白质组学研究血清生物标志物与赫赛汀疗效相关性及其分子机制

Due to the characters of its strong invasion, metastasis ability and high recurrence frequency, HER-2 positive breast cancer becomes one of major troubles of breast cancer clinical therapy. Herceptin is currently the main drug for clinical therapy of HER-2 positive breast cancer, but drug resistance limits its application. Our previous study showed that serum IGFBP5 had significantly higher expression in Herceptin resistant HER-2 positive breast cancer using a developed LC-MS/MS based pharmaco-targeted proteomics. On the other hand, literature retrieval and cell experiments suggested that IGFBP5 might play a biological role. Additional bioinformatics analysis indicated that CXCR1 could be a candidate target protein of IGFBP5. On the basis of previous research, we further optimized the developed LC-MS/MS based pharmaco-targeted proteomics and applied this approach into the expanded samples, to clarify the relationship between serum IGFBP5 and herceptin response. Moreover, over expression and knock down strategies were used to illuminate the effect of IGFBP5 on regulation Herceptin resistance; subsequently analyze the underlying mechanism between IGFBP5 and CXCR1 protein. To date, there was no report about the function and mechanism of IGFBP5 in the regulating the herceptin resistance of HER-2 positive breast cancer, and our study may provide a new biomarker for HER-2 positive breast cancer therapy and intervention targets.

HER-2阳性乳腺癌由于侵袭转移能力强、复发率高，是乳腺癌临床治疗的重大难题。赫赛汀是目前临床用于治疗HER-2阳性乳腺癌的主要药物，但耐药限制了它的应用。前期研究中，我们通过建立基于质谱的药物定向蛋白质组学方法测定血清蛋白含量发现，血清IGFBP5在赫赛汀耐药的HER-2阳性乳腺癌显著高表达；文献检索和细胞实验提示IGFBP5可能发挥生物学功能；生物信息学分析发现CXCR1可能为IGFBP5作用蛋白。本项目拟在已有研究基础上，进一步优化已建立的药物定向蛋白质组学方法，对扩大的样本进行检测，明确IGFBP5与赫赛汀应答的关系。同时采用过表达和干扰策略，明确IGFBP5对赫赛汀耐药的影响；并以CXCR1为机制主线，探讨IGFBP5与CXCR1的相互作用及调控机制。本课题具有源头创新性，将有望为HER-2阳性乳腺癌的精准治疗提供新的生物标志物和干预靶标。

人表皮生长因子受体2（HER2）阳性是一种侵袭性特别强的乳腺癌。以曲妥珠单抗为基础的治疗是HER2阳性乳腺癌的标准治疗方法，但有些患者对该疗法产生了耐药性。血清蛋白已被用于预测各种癌症的治疗效果，但血清蛋白是否可以作为HER2阳性乳腺癌的生物标志物尚不清楚。采用基于等压力串联质谱标记（TMT）的定量蛋白质组学方法，我们在曲妥珠单抗治疗耐药患者治疗前的血清中发现了18种差异表达的蛋白质。然后，利用基于LC–MS/MS的多反应监测定量方法选择并验证了四种蛋白质，并证实了三种蛋白质（SRGN、LDHA和CST3）与曲妥珠单抗治疗耐药相关。最后，根据这三种蛋白的水平，通过logistic回归模型计算并获得以曲妥珠单抗为基础的抗药性诊断得分。综上所述，我们开发了一种基于血清蛋白质含量为基础的风险评分，它可以预测以曲妥珠单抗为基础的治疗HER2阳性乳腺癌患者的疗效。