Department of Pharmacy, Jingmen No.1 People's Hospital, No.3, Shenzhen Avenue, Duodao District, Jingmen, 448000, Hubei, China.
J Orthop Surg Res. 2021 Aug 18;16(1):510. doi: 10.1186/s13018-021-02631-y.
The occurrence of chemoresistance is a common problem in tumor treatment. Circular RNA (circRNA) has been confirmed to be related to tumor chemoresistance. However, the role and the underlying molecular mechanism of hsa_circ_0004674 in the chemoresistance of osteosarcoma (OS) are still unclear.
The expression of hsa_circ_0004674, miR-342-3p, and fibrillin-1 (FBN1) was determined by qRT-PCR. Cell counting kit 8 assay was used to evaluate the doxorubicin (DXR) resistance of cells. The proliferation and apoptosis of cells were measured using colony formation assay and flow cytometry. Western blot analysis was utilized to examine the protein levels of resistance markers, Wnt/β-catenin pathway markers and FBN1. The interaction between miR-342-3p and hsa_circ_0004674 or FBN1 was confirmed by dual-luciferase reporter assay and RNA pull-down assay. Moreover, animal experiments were performed to assess the effect of hsa_circ_0004674 silencing on the DXR sensitive of OS in vivo.
The upregulated hsa_circ_0004674 was found in DXR-resistant OS tissues and cells. Knockdown of hsa_circ_0004674 could inhibit the DXR resistance of OS cells in vitro and promote the DXR sensitive of OS tumors in vivo. In addition, we discovered that hsa_circ_0004674 could sponge miR-342-3p, and miR-342-3p could target FBN1. MiR-342-3p inhibitor could reverse the inhibition effect of hsa_circ_0004674 knockdown on the DXR resistance of OS cells. Similarly, the suppressive effect of miR-342-3p on the DXR resistance of OS cells also could be reversed by FBN1 overexpression. Furthermore, we revealed that hsa_circ_0004674 silencing inhibited the activity of Wnt/β-catenin pathway by the miR-342-3p/FBN1 axis.
Hsa_circ_0004674 facilitated the DXR resistance of OS through Wnt/β-catenin pathway via regulating the miR-342-3p/FBN1 axis, suggesting that hsa_circ_0004674 was a promising target for the chemoresistance of OS.
化疗耐药的发生是肿瘤治疗中的一个常见问题。环状 RNA（circRNA）已被证实与肿瘤化疗耐药有关。然而，hsa_circ_0004674 在骨肉瘤（OS）化疗耐药中的作用及其潜在的分子机制尚不清楚。
通过 qRT-PCR 检测 hsa_circ_0004674、miR-342-3p 和原纤维蛋白 1（FBN1）的表达。用细胞计数试剂盒 8 检测细胞对阿霉素（DXR）的耐药性。通过集落形成实验和流式细胞术检测细胞的增殖和凋亡。用 Western blot 分析检测耐药标志物、Wnt/β-catenin 通路标志物和 FBN1 的蛋白水平。通过双荧光素酶报告基因检测和 RNA 下拉实验证实 miR-342-3p 与 hsa_circ_0004674 或 FBN1 的相互作用。此外，还进行了动物实验以评估 hsa_circ_0004674 沉默对体内 OS 的 DXR 敏感性的影响。
在 DXR 耐药的骨肉瘤组织和细胞中发现 hsa_circ_0004674 上调。hsa_circ_0004674 的敲低可抑制 OS 细胞的 DXR 耐药性，并促进体内 OS 肿瘤对 DXR 的敏感性。此外，我们发现 hsa_circ_0004674 可以海绵吸附 miR-342-3p，miR-342-3p 可以靶向 FBN1。miR-342-3p 抑制剂可逆转 hsa_circ_0004674 敲低对 OS 细胞 DXR 耐药性的抑制作用。同样，miR-342-3p 对 OS 细胞 DXR 耐药性的抑制作用也可被 FBN1 过表达逆转。此外，我们揭示 hsa_circ_0004674 沉默通过 miR-342-3p/FBN1 轴抑制 Wnt/β-catenin 通路的活性。
hsa_circ_0004674 通过调节 miR-342-3p/FBN1 轴促进 OS 的 DXR 耐药性，通过 Wnt/β-catenin 通路，提示 hsa_circ_0004674 是骨肉瘤化疗耐药的一个有前途的靶点。
