4月12日发表在《细胞》杂志的一项研究论文中,北卡罗莱纳大学教堂山分校研究人员介绍一种蛋白激酶测试技术可以研究癌症抗药性的机制,为肿瘤联合疗法的确定提供判断依据。
激酶在人体组织中发挥关键作用,特别是对癌症细胞的生长尤为重要。在518个已知的人类激酶中,约400个在癌症中表达,但在肿瘤中有哪一种激酶以及多少激酶是实际发挥作用的很难衡量。癌症研究人员为开发激酶抑制剂治疗癌症付出了巨大努力,一些药物也已经上市如Herceptin、Tykerb和Gleevec。然而,尽管这一类抗癌药物的有效性,但大多数癌症最终还是会产生耐药性。UNC研究团队开发出一种测试,可以测量所有存在和活动的激酶的60-70%,使研究者了解癌症如何逃避激酶抑制剂的治疗,使研究人员能够结合药物来阻止耐药性产生。
Gary Johnson博士,该研究的主要领导者说:单药激酶抑制剂的运用往往在实践中失败,因为肿瘤蛋白激酶的网络会学会如何处理这些抑制剂,导致快速药物抵抗。我们对我们实验室已开发的测试技术感到非常兴奋,因为它的工作原理在乳腺癌模型中得到很好运用,能很好地预测联合疗法的成功。Johnson医学博士是UNC医学院凯南特聘教授和药理学部门主席,也是UNC莱恩伯格综合癌症中心的成员。
研究人员表示:作为一个肿瘤学家,最令人沮丧的事情之一是当肿瘤病人接受治疗时产生耐药性。我们很高兴能检查在激酶抑制剂治疗前、中以及后肿瘤标本的激酶变化情况。
该小组希望能够在癌症治疗期间使用新的测试技术跟踪研究激酶“重新编程”过程,以确定什么样的药物组合将阻止癌症耐药性的产生。该测试技术的专利申请已提交。(生物谷:Bioon.com)
doi:10.1016/j.cell.2012.02.053
PMC:
PMID:
Dynamic Reprogramming of the Kinome in Response to Targeted MEK Inhibition in Triple-Negative Breast Cancer
James S. Duncan, Martin C. Whittle, Kazuhiro Nakamura, Amy N. Abell, Alicia A. Midland, Jon S. Zawistowski, Nancy L. Johnson, Deborah A. Granger, Nicole Vincent Jordan, David B. Darr et al
Kinase inhibitors have limited success in cancer treatment because tumors circumvent their action. Using a quantitative proteomics approach, we assessed kinome activity in response to MEK inhibition in triple-negative breast cancer (TNBC) cells and genetically engineered mice (GEMMs). MEK inhibition caused acute ERK activity loss, resulting in rapid c-Myc degradation that induced expression and activation of several receptor tyrosine kinases (RTKs). RNAi knockdown of ERK or c-Myc mimicked RTK induction by MEK inhibitors, and prevention of proteasomal c-Myc degradation blocked kinome reprogramming. MEK inhibitor-induced RTK stimulation overcame MEK2 inhibition, but not MEK1 inhibition, reactivating ERK and producing drug resistance. The C3Tag GEMM for TNBC similarly induced RTKs in response to MEK inhibition. The inhibitor-induced RTK profile suggested a kinase inhibitor combination therapy that produced GEMM tumor apoptosis and regression where single agents were ineffective. This approach defines mechanisms of drug resistance, allowing rational design of combination therapies for cancer.