Department of Stomatology, The First Affiliated Hospital of Jinzhou Medical University, Jinzhou, Liaoning, China.
Department of Pathology, The Fourth Hospital of Jinan, Jinan, Shandong, China.
Cell Biochem Funct. 2020 Oct;38(7):943-954. doi: 10.1002/cbf.3520. Epub 2020 Apr 23.
Growing data have recognized the significance of Response Gene to Complement (RGC)-32 in numerous tumour developments. Notwithstanding, the functional role and underlying mechanism of it in tongue squamous cell carcinoma (TSCC) remain enigmatic. Here, to identify the impact of RGC-32 in TSCC, its expression in multiple TSCC cells was measured and loss-of-function experiments in cell lines were performed to illuminate the function of it induced TSCC progression, via si-RNA knockdown, CCK-8, colony formation, wound-healing, transwell, flow cytometry and western blot assays. To clarify potential mechanism, expressions of hallmarks in epithelial-mesenchymal transition (EMT) process and PI3K/AKT signalling were assessed, and the upstream miR regulator of RGC-32 was predicted and verified by applying bioinformatic approaches and dual-luciferase reporter assay, respectively. Finally, the rescue experiments were applied to better elucidate the effect of miR-26b/RGC-32 axis in TSCC behaviours. As a result, RGC-32 was upregulated in TSCC cells and knocking down of it abrogated cell proliferation, trans-migration and invasion, whilst promoted apoptosis in TSCC, which was regulated through repressing EMT and inactivation of PI3K/AKT signalling. Subsequently, miR-26b was predicted and identified as an upstream regulator of RGC-32, and the pro-tumorigenic effect of RGC-32 was reversed by miR-26b overexpression. Collectively, our results demonstrated that RGC-32 facilitated TSCC progression, which was modulated by activations of PI3K/AKT pathway and EMT process, and reduction of its negative regulator of miR-26b. These findings highlight a novel role of miR-26b/RGC-32 axis in TSCC and underlying mechanism, encouraging a potent usage in TSCC treatment. SIGNIFICANCE OF THE STUDY: We first uncovered that Response Gene to Complement-32 played a significantly pro-tumorigenic role in tongue squamous cell carcinoma (TSCC), which was closely regulated by downregulation of miR-26b and activations of epithelial-mesenchymal transition process and PI3K/AKT signalling. These findings contribute to better understand the molecular mechanism in carcinogenesis of TSCC, and shed some light on promising strategy for TSCC therapeutics.
越来越多的数据表明，补体反应基因（RGC）-32 在多种肿瘤的发展中具有重要意义。然而，其在舌鳞状细胞癌（TSCC）中的功能作用和潜在机制仍不清楚。在这里，为了确定 RGC-32 在 TSCC 中的作用，我们测量了多种 TSCC 细胞中的表达，并通过 si-RNA 敲低、CCK-8、集落形成、划痕愈合、transwell、流式细胞术和 Western blot 实验，在细胞系中进行了功能丧失实验，以阐明它诱导 TSCC 进展的功能。为了阐明潜在的机制，评估了上皮-间充质转化（EMT）过程和 PI3K/AKT 信号通路中的标志性表达，并分别应用生物信息学方法和双荧光素酶报告基因实验预测和验证了 RGC-32 的上游 miR 调节物。最后，应用挽救实验来更好地阐明 miR-26b/RGC-32 轴在 TSCC 行为中的作用。结果表明，RGC-32 在 TSCC 细胞中上调，敲低它可阻止细胞增殖、迁移和侵袭，同时促进 TSCC 细胞凋亡，这是通过抑制 EMT 和失活 PI3K/AKT 信号通路来调节的。随后，预测并鉴定 miR-26b 为 RGC-32 的上游调节物，过表达 miR-26b 可逆转 RGC-32 的促肿瘤作用。总之，我们的研究结果表明，RGC-32 促进了 TSCC 的进展，这是由 PI3K/AKT 通路和 EMT 过程的激活以及其负调节因子 miR-26b 的减少所调节的。这些发现突出了 miR-26b/RGC-32 轴在 TSCC 中的新作用及其潜在机制，为 TSCC 的治疗提供了有力的依据。
我们首次发现，补体反应基因-32 在舌鳞状细胞癌（TSCC）中发挥了显著的促肿瘤作用，其受到 miR-26b 的下调以及上皮-间充质转化过程和 PI3K/AKT 信号通路的激活的紧密调节。这些发现有助于更好地了解 TSCC 发生过程中的分子机制，并为 TSCC 的治疗提供了有前途的策略。
