PDF(Pubmed)
Abstract：
HER2-targeted therapies, such as Trastuzumab (Tz), have significantly improved the clinical outcomes for patients with HER2+ breast cancer (BC). However, treatment resistance remains a major obstacle. To elucidate functional and metabolic changes associated with acquired resistance, we characterized protein profiles of BC Tz-responder spheroids (RSs) and non-responder spheroids (nRSs) by a proteomic approach. Three-dimensional cultures were generated from the HER2+ human mammary adenocarcinoma cell line BT-474 and a derived resistant cell line. Before and after a 15-day Tz treatment, samples of each condition were collected and analyzed by liquid chromatography-mass spectrometry. The analysis of differentially expressed proteins exhibited the deregulation of energetic metabolism and mitochondrial pathways. A down-regulation of carbohydrate metabolism and up-regulation of mitochondria organization proteins, the tricarboxylic acid cycle, and oxidative phosphorylation, were observed in nRSs. Of note, Complex I-related proteins were increased in this condition and the inhibition by metformin highlighted that their activity is necessary for nRS survival. Furthermore, a correlation analysis showed that overexpression of Complex I proteins NDUFA10 and NDUFS2 was associated with high clinical risk and worse survival for HER2+ BC patients. In conclusion, the non-responder phenotype identified here provides a signature of proteins and related pathways that could lead to therapeutic biomarker investigation.
摘要：
HER2靶向治疗,如曲妥珠单抗(Tz)，显著改善了HER2+乳腺癌（BC）患者的临床预后。然而,治疗阻力仍然是一个主要障碍。为了阐明与获得性抗性相关的功能和代谢变化，我们通过蛋白质组学方法表征了BCTz反应球体（RSs）和非反应球体（nRSs）的蛋白质谱。从HER2+人乳腺腺癌细胞系BT-474和衍生的抗性细胞系产生三维培养物。在15天的Tz治疗之前和之后，收集每种条件的样品，并通过液相色谱-质谱分析。差异表达蛋白质的分析显示能量代谢和线粒体途径的失调。碳水化合物代谢的下调和线粒体组织蛋白的上调，三羧酸循环，和氧化磷酸化，在NRS中观察到。值得注意的是，在这种情况下，复合物I相关蛋白增加，二甲双胍的抑制作用强调了它们的活性是nRS存活所必需的。此外，相关分析显示,在HER2+BC患者中,复合物I蛋白NDUFA10和NDUFS2的过度表达与高临床风险和低生存率相关.总之,此处鉴定的无应答者表型提供了可能导致治疗性生物标志物研究的蛋白质和相关途径的特征.
