Dong Xiaoya, Fang Zhigang, Yu Mingxue, Zhang Ling, Xiao Ruozhi, Li Xudong, Pan Guangjin, Liu Jiajun
Department of Hematology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
Guangzhou Academy of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou, China.
Cell Physiol Biochem. 2018;51(2):886-896. doi: 10.1159/000495387. Epub 2018 Nov 22.
BACKGROUND/AIMS: Among different molecular candidates, there is growing data to support that long noncoding RNAs (lncRNAs) play a significant role in acute myeloid leukemia (AML). HOXA-AS2 is significantly overexpressed in a variety of tumors and associated with anti-cancer drug resistance, however, little is known regarding the expression and function of HOXA-AS2 in the chemoresistance of AML. In this study, we aimed to determine the role and molecular mechanism of HOXA-AS2 in adriamycin-based chemotherapy resistance in AML cells.
Quantitative real-time PCR was used to detect HOXA-AS2 expression in the BM samples and ADR cell lines, U/A and T/A cells. Furthermore, the effects of HOXA-AS2 silencing on cell proliferation and apoptosis were assessed in vitro by CCK8 and flow cytometry, and on tumor growth in vivo. Furthermore, bioinformatics online programs predicted and luciferase reporter assay were used to validate the association of HOXA-AS2 and miR-520c-3p in AML.
In this study, we showed that HOXA-AS2 is significantly upregulated in BM samples from AML patients after treatment with adriamycin-based chemotherapy and in U/A and T/A cells. Knockdown of HOXA-AS2 inhibited ADR cell proliferation in vitro and in vivo and promoted apoptosis. Bioinformatics online programs predicted that HOXA-AS2 sponge miR-520c-3p at 3'-UTR with complementary binding sites, which was validated using luciferase reporter assay and anti-Ago2 RIP assay. HOXA-AS2 could negatively regulate the expression of miR-520c-3p in ADR cells. S100A4 was predicted as a downstream target of miR-520c-3p, which was confirmed by luciferase reporter assay.
Our results suggest that HOXA-AS2 plays an important role in the resistance of AML cells to adriamycin. Thus, HOXA-AS2 may represent a therapeutic target for overcoming resistance to adriamycin-based chemotherapy in AML.
背景/目的：在不同的分子候选物中，越来越多的数据支持长链非编码RNA（lncRNA）在急性髓系白血病（AML）中发挥重要作用。HOXA-AS2在多种肿瘤中显著过表达，并与抗癌药物耐药性相关，然而，关于HOXA-AS2在AML化疗耐药中的表达和功能知之甚少。在本研究中，我们旨在确定HOXA-AS2在AML细胞基于阿霉素的化疗耐药中的作用和分子机制。
采用定量实时PCR检测骨髓样本和阿霉素耐药细胞系U/A和T/A细胞中HOXA-AS2的表达。此外，通过CCK8和流式细胞术在体外评估HOXA-AS2沉默对细胞增殖和凋亡的影响，以及对体内肿瘤生长的影响。此外，利用生物信息学在线程序进行预测，并通过荧光素酶报告基因检测验证AML中HOXA-AS2与miR-520c-3p的关联。
在本研究中，我们发现HOXA-AS2在接受基于阿霉素化疗的AML患者的骨髓样本以及U/A和T/A细胞中显著上调。敲低HOXA-AS2可在体外和体内抑制阿霉素耐药细胞增殖并促进凋亡。生物信息学在线程序预测HOXA-AS2在3'-UTR处与miR-520c-3p有互补结合位点，通过荧光素酶报告基因检测和抗Ago2 RIP检测进行了验证。HOXA-AS2可负向调节阿霉素耐药细胞中miR-520c-3p的表达。S100A4被预测为miR-520c-3p的下游靶点，荧光素酶报告基因检测证实了这一点。
我们的结果表明HOXA-AS2在AML细胞对阿霉素的耐药中起重要作用。因此，HOXA-AS2可能是克服AML中基于阿霉素化疗耐药的治疗靶点。
