Loss of DOK2 induces carboplatin resistance in ovarian cancer via suppression of apoptosis
Loss of DOK2 induces carboplatin resistance in ovarian cancer via suppression of apoptosis
复制标题
DOI：
10.1016/j.ygyno.2013.05.002
复制
发表时间：
2013-08-01
影响因子：
4.7
通讯作者：
Lucito, Robert
中科院分区：
文献类型：
--
作者：
Lum, Elena;Vigliotti, Michele;Lucito, Robert
Objective.卵巢癌是高度异质性的，虽然化疗是首选的治疗方法，但许多患者具有内在耐药性或迅速产生耐药性。此外，所有复发的肿瘤最终都会产生耐药性。最近的证据表明，表观遗传失调可能是一个关键因素的发病和维持的化疗耐药性。我们着手鉴定影响耐药性的表观遗传学沉默基因。分析总共45个卵巢样品的表观基因组以鉴定与铂反应分离的表观遗传改变的基因，并进一步用表达数据过滤以鉴定被抑制的基因。组织培养卡铂耐药筛选用于功能验证这组候选铂耐药基因。我们的筛选正确地鉴定了19个基因，这些基因在被抑制时改变了培养物中细胞的化学抗性。在筛选中鉴定的基因中，我们进一步表征了一个基因，对接蛋白2（DOK2），酪氨酸激酶下游的衔接蛋白，以确定我们是否可以阐明它增加抗性的机制。DOK2的缺失降低了卡铂诱导的细胞凋亡水平。此外，在DOK2减少的细胞中，失巢凋亡水平降低。我们已经开发了一种筛选方法，分析表观基因组和信息识别候选基因，然后在体外培养筛选的候选基因。为了验证我们的筛选方法，我们进一步表征了一个候选基因DOK2，并表明DOK2的缺失通过降低对治疗的细胞凋亡水平来诱导化疗耐药性。(C)2013作者爱思唯尔公司出版All rights reserved.
Objective. Ovarian cancers are highly heterogeneous and while chemotherapy is the preferred treatment many patients are intrinsically resistant or quickly develop resistance. Furthermore, all tumors that recur ultimately become resistant. Recent evidence suggests that epigenetic deregulation may be a key factor in the onset and maintenance of chemoresistance. We set out to identify epigenetically silenced genes that affect chemoresistance.Methods. The epigenomes of a total of 45 ovarian samples were analyzed to identify epigenetically altered genes that segregate with platinum response, and further filtered with expression data to identify genes that were suppressed. A tissue culture carboplatin resistance screen was utilized to functionally validate this set of candidate platinum resistance genes.Results. Our screen correctly identified 19 genes that when suppressed altered the chemoresistance of the cells in culture. Of the genes identified in the screen we further characterized one gene, docking protein 2 (DOK2), an adapter protein downstream of tyrosine kinase, to determine if we could elucidate the mechanism by which it increased resistance. The loss of DOK2 decreased the level of apoptosis in response to carboplatin. Furthermore, in cells with reduced DOK2, the level of anoikis was decreased.Conclusions. We have developed a screening methodology that analyzes the epigenome and informatically identifies candidate genes followed by in vitro culture screening of the candidate genes. To validate our screening methodology we further characterized one candidate gene, DOK2, and showed that loss of DOK2 induces chemotherapy resistance by decreasing the level of apoptosis in response to treatment. (C) 2013 The Authors. Published by Elsevier Inc. All rights reserved.