Department of Bone Metabolism, School and Hospital of Stomatology, Cheeloo College of Medicine, Shandong University & Shandong Key Laboratory of Oral Tissue Regeneration & Shandong Engineering Laboratory for Dental Materials and Oral Tissue Regeneration, Jinan 250012, China.
Department of Orthodontics, Sichuan University, West China Hospital of Stomatology, State Key laboratory of Oral Diseases, National Clinical Research Center of Oral Diseases, Chengdu 610041, China.
Int J Biochem Cell Biol. 2022 Dec;153:106316. doi: 10.1016/j.biocel.2022.106316. Epub 2022 Oct 22.
Notum, which belongs to the α/β hydrolase family, is a deacylated extracellular protein that regulates the Wnt signaling pathway. Studies have found that Notum participates in the progression of colorectal cancer and hepatocellular carcinoma, but its role in oral squamous cell carcinoma (OSCC) is currently unclear. This study aimed to explore the role of Notum in regulating OSCC and further reveal the underlying mechanisms. Various approaches including bioinformatics analysis, enzyme-linked immunosorbent assay and immunohistochemical staining were used to detect the expression of Notum in OSCC cells and tissues. Cell counting kit-8 assay, clone formation assay, wound healing assay, transwell assay and in-gel zymography assay were explored to evaluate the regulation of Notum in OSCC proliferation and migration. Hoechst 33342/PI assay, cell immunofluorescence, flow cytometry and in vivo tumorigenesis experiment were applied for OSCC apoptosis. Real-time quantitative polymerase chain reaction analysis was performed for mRNA level while western blotting was conducted to detect protein expression. The results showed that Notum was highly expressed in OSCC tissues and cells, and Notum promoted the proliferation and migration of OSCC cells while it inhibited their apoptosis. Furthermore, signaling pathway analysis showed that Notum led to potential pro-survival of OSCC through crosstalk between sonic hedgehog (Shh) and Wnt/β-catenin signaling via phosphorylation of glycogen synthase kinase-3 beta. These results will help to elucidate the mechanism and also provide new ideas for targeted treatment of OSCC.
Notum 属于 α/β 水解酶家族，是一种去酰化的细胞外蛋白，可调节 Wnt 信号通路。研究发现，Notum 参与结直肠癌和肝细胞癌的进展，但它在口腔鳞状细胞癌（OSCC）中的作用目前尚不清楚。本研究旨在探讨 Notum 在调节 OSCC 中的作用，并进一步揭示其潜在机制。采用生物信息学分析、酶联免疫吸附试验和免疫组织化学染色等多种方法检测 OSCC 细胞和组织中 Notum 的表达。通过细胞计数试剂盒-8 测定、克隆形成测定、划痕愈合测定、Transwell 测定和凝胶酶谱分析，探讨 Notum 对 OSCC 增殖和迁移的调节作用。采用 Hoechst 33342/PI 测定、细胞免疫荧光、流式细胞术和体内肿瘤生成实验评估 OSCC 细胞凋亡。采用实时定量聚合酶链反应分析检测 mRNA 水平，采用 Western blot 检测蛋白表达。结果表明，Notum 在 OSCC 组织和细胞中高表达，Notum 促进 OSCC 细胞的增殖和迁移，同时抑制其凋亡。此外，信号通路分析表明，Notum 通过磷酸化糖原合酶激酶-3β，导致 Sonic Hedgehog（Shh）和 Wnt/β-catenin 信号通路之间的串扰，从而导致 OSCC 的潜在存活。这些结果将有助于阐明机制，并为 OSCC 的靶向治疗提供新的思路。
