The la autoantigen is a malignancy-associated cell death target that is induced by DNA-damaging drugs
The la autoantigen is a malignancy-associated cell death target that is induced by DNA-damaging drugs
复制标题
DOI：
10.1158/1078-0432.ccr-07-0922
复制
发表时间：
2007-09-15
影响因子：
11.5
通讯作者：
Brown, Michael P.
中科院分区：
文献类型：
--
作者：
Al-Ejeh, Fares;Darby, Jocelyn M.;Brown, Michael P.
目的：评价La自身抗原作为dna损伤化疗后死亡癌细胞特异性单克隆抗体（mAb）结合的靶点。实验设计：利用免疫印迹和流式细胞术进行了la -特异性3139单抗与恶性和正常原代细胞结合的体外研究，并进行了细胞毒性药物治疗和不治疗。染色质结合研究和γ - H2AX作为DNA双链断裂标记物的免疫荧光检测，以及3139结合试验来测量DNA损伤反应。研究了转谷氨酰胺酶2 （TG2）底物的掺入和TG2的抑制作用，以测量死细胞中的蛋白质交联。结果：La在人癌细胞系中较正常原代细胞高表达。在dna损伤刺激后的3小时内，当La与γ - H2AX共定位时，它成为染色质结合。随后，在刺激导致细胞死亡后，La-specific 3139 mAb特异性和优先结合在死亡癌细胞的细胞质中。此外，3139与死亡癌细胞的结合随着DNA损伤的增加而增加。La和3139都通过TG2活性在死亡的癌细胞中交联。结论：La自身抗原在dna损伤化疗后死亡的癌细胞中选择性表达，是确定化疗反应的一个有希望的癌细胞死亡靶点。
Purpose: To evaluate the La autoantigen as a target for specific monoclonal antibody (mAb) binding in dead cancer cells after use of DNA-damaging chemotherapy.Experimental Design: In vitro studies of La-specific 3139 mAb binding to malignant and normal primary cells with and without cytotoxic drug treatment were done using immunoblotting and flow cytometry. Chromatin-binding studies and immunofluorescence detection of gamma H2AX as a marker of DNA double-stranded breaks together with 3139 binding assays were done to measure DNA damage responses. Incorporation of a transglutaminase 2 (TG2) substrate and TG2 inhibition were studied to measure protein cross-linking in dead cells.Results: La was overexpressed in human cancer cell lines with respect to normal primary cells. Within 3 h of the DNA-damaging stimulus, La became chromatin bound when it colocalized with,gamma H2AX. Later, after the stimulus produced cell death, La-specific 3139 mAb bound specifically and preferentially in the cytoplasm of dead cancer cells. Moreover, 3139 binding to dead cancer cells increased with increasing DNA damage. Both La and 3139 became cross-linked in dead cancer cells via TG2 activity.Conclusion: La autoantigen represents a promising cancer cell death target to determine chemotherapy response because its expression was selectively induced in dead cancer cells after DNA-damaging chemotherapy.