Wang Xiaoting, Huang Jun, You Ruolan, Hou Diyu, Liu Jingru, Wu Long, Yao Meihong, Yang Fuwen, Huang Huifang
Central Laboratory, Fujian Medical University Union Hospital, 29 Xinquan Road, Fuzhou, 350001, Fujian, China.
Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, China.
Protoplasma. 2023 Nov;260(6):1569-1580. doi: 10.1007/s00709-023-01873-3. Epub 2023 Jun 20.
ITGA5, a fibronectin receptor was highly expressed in laryngeal squamous cell carcinoma (LSCC) samples and was related to poor survival. However, the potential mechanism remains unclear. To elucidate the regulatory role of ITGA5 in LSCC progression, we investigated the effect of ITGA5 expression on lymphangiogenesis, migration, and invasion of LSCC cells in vitro and in vivo using immunohistochemistry, siRNA transfection, qRT-PCR, western blotting, enzyme-linked immunosorbent assay, flow cytometry, transwell co-culture, tube formation, cell migration, and invasion assays, and a subcutaneous graft tumor model. The expression of ITGA5 was higher in the LSCC tissues and linked to lymph node metastasis and T staging. Moreover, ITGA5 expression was significantly positively correlated with VEGF-C expression, and the lymphatic vessel density of patients with high ITGA5 expression was noticeably higher than that of patients with low ITGA5 expression. Additionally, it was found in vitro that downregulation of ITGA5 expression not only inhibited the expression and secretion of VEGF-C, but also suppressed the tube-forming ability of human lymphatic endothelial cells (HLECs) and the migration and invasion ability of LSCC cells, while exogenous VEGF-C supplementation reversed these phenomena. Furthermore, a tumor xenograft assay showed that si-ITGA5 restrained the growth and metastasis of TU212-derived tumors in vivo. Our findings suggested that ITGA5 induces lymphangiogenesis and LSCC cell migration and invasion by enhancing VEGF-C expression and secretion.
整合素α5（ITGA5）是一种纤连蛋白受体，在喉鳞状细胞癌（LSCC）样本中高表达，且与患者预后不良相关。然而，其潜在机制仍不清楚。为阐明ITGA5在LSCC进展中的调控作用，我们采用免疫组织化学、小干扰RNA（siRNA）转染、实时定量聚合酶链反应（qRT-PCR）、蛋白质免疫印迹法、酶联免疫吸附测定、流式细胞术、Transwell共培养、管腔形成、细胞迁移和侵袭实验以及皮下移植瘤模型，在体内外研究了ITGA5表达对LSCC细胞淋巴管生成、迁移和侵袭的影响。ITGA5在LSCC组织中的表达较高，且与淋巴结转移和T分期相关。此外，ITGA5表达与血管内皮生长因子C（VEGF-C）表达显著正相关，ITGA5高表达患者的淋巴管密度明显高于ITGA5低表达患者。另外，体外研究发现，下调ITGA5表达不仅抑制VEGF-C的表达和分泌，还抑制人淋巴管内皮细胞（HLEC）的管腔形成能力以及LSCC细胞的迁移和侵袭能力，而外源性补充VEGF-C可逆转这些现象。此外，肿瘤异种移植实验表明，si-ITGA5在体内抑制了TU212来源肿瘤的生长和转移。我们的研究结果表明，ITGA5通过增强VEGF-C的表达和分泌诱导淋巴管生成以及LSCC细胞的迁移和侵袭。
