Zhao Fangfang, Pu Youguang, Cui Mingda, Wang Haiyan, Cai Shanbao
Cancer Epigenetics Program, Anhui Cancer Hospital, West Branch of Anhui Provincial Hospital, Anhui Medical University, Hefei, 230031 Anhui China.
Xinxiang Medical University, Xinxiang, 453003 Henan China.
Cancer Cell Int. 2017 Nov 2;17:100. doi: 10.1186/s12935-017-0470-2. eCollection 2017.
As one of the hallmarks of cancer, chemoresistance hinders curative cancer chemotherapy in osteosarcoma (OS). MicroRNAs (miRNAs) act as key regulators of gene expression in diverse biological processes including the multi-chemoresistance of cancers.
Based on the CCK8 experiments, we performed an RNA-seq-based miR-omic analysis of osteosarcoma (OS) cells (a multi-chemosensitive OS cell line G-292 and a multi-chemoresistant OS cell line SJSA-1) to detect the levels of miR-20a-5p. We predicted syndecan 2 (SDC2) as one of the target genes of miR-20a-5p via several websites, which was further validated by detecting their expression of both mRNA and protein level in both the miR-20a-5p-mimic transfected G-292 and miR-20a-5p-antagomiR transfected SJSA-1 cells. The involvement of SDC2 with OS chemoresistance was checked by siRNA-mediated repression or overexpression of SDC2 gene. Cell viability was assessed by CCK8 assay.
We found that the miR-20a-5p level was higher in G-292 cells than in SJSA-1 cells. Forced expression of miR-20a-5p counteracted OS chemoresistance in both cell culture and tumor xenografts in nude mice. As one of miR-20a-5p's targets, SDC2 was found to mediate the miR-20a-5p-induced repression of OS chemoresistance.
Our results suggest that miR-20a-5p and SDC2 contribute to OS chemoresistance. The key players in the miR-20a-5p/SDC2 axis may be a potential diagnostic biomarker and therapeutic target for OS patients.
化疗耐药作为癌症的标志之一,阻碍了骨肉瘤(OS)的根治性化疗。微小RNA(miRNA)在包括癌症多药耐药在内的多种生物学过程中作为基因表达的关键调节因子。
基于CCK8实验,我们对骨肉瘤(OS)细胞(多化学敏感的OS细胞系G - 292和多化学耐药的OS细胞系SJSA - 1)进行了基于RNA测序的miR组分析,以检测miR - 20a - 5p的水平。我们通过多个网站预测syndecan 2(SDC2)是miR - 20a - 5p的靶基因之一,并通过检测miR - 20a - 5p模拟物转染的G - 292细胞和miR - 20a - 5p拮抗剂转染的SJSA - 1细胞中mRNA和蛋白质水平的表达进一步验证。通过siRNA介导的SDC2基因抑制或过表达来检查SDC2与OS化疗耐药的关系。通过CCK8测定评估细胞活力。
我们发现G - 292细胞中miR - 20a - 5p水平高于SJSA - 1细胞。在细胞培养和裸鼠肿瘤异种移植中,miR - 20a - 5p的强制表达均抵消了OS化疗耐药。作为miR - 20a - 5p的靶标之一,发现SDC2介导miR - 20a - 5p诱导的OS化疗耐药抑制。
我们的结果表明miR - 20a - 5p和SDC2促成了OS化疗耐药。miR - 20a - 5p/SDC2轴中的关键分子可能是OS患者潜在的诊断生物标志物和治疗靶点。