Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, Suzhou 215123, China; Jiangsu Key Laboratory of Clinical Immunology, Soochow University, Suzhou 215123, China; Department of Gastroenterology, The First Affiliated Hospital of Soochow University, Suzhou 215000, China; Department of Oncology, The First Affiliated Hospital of Naval Military Medical University, Shanghai 200003, China.
Jiangsu Key Laboratory of Clinical Immunology, Soochow University, Suzhou 215123, China; Department of Gastroenterology, The First Affiliated Hospital of Soochow University, Suzhou 215000, China.
Tissue Cell. 2024 Oct;90:102518. doi: 10.1016/j.tice.2024.102518. Epub 2024 Aug 10.
Aberrant expression of B7 homolog 3 protein (B7-H3) has been detected in various cancers including colorectal cancer (CRC) and implicated in modulating multiple biological functions of CRC cells. However, its role in CRC metastasis has not yet been determined. This study aims to explore and unravel the underlying mechanisms through which B7-H3 contributes to migration, invasion and actin cytoskeleton in CRC.
The expression of B7-H3 and LIMK1 in CRC tumor samples was determined by IHC staining. Transwell and F-actin immunofluorescence staining assays were performed to explore the role of B7-H3 in migration, invasion and actin filament accumulating of CRC cells. RNA-seq and Western blot assays were used to investigate the molecular mechanisms.
B7-H3 was highly expressed in CRC tissues and positively associated with poor prognosis of CRC patients by immunohistochemistry. Migration and invasion assays showed that B7-H3 knockdown significantly inhibited the migration and invasion of CRC cells. B7-H3 overexpression had the opposite effect. Moreover, we determined that B7-H3 could regulate actin cytoskeleton and the RhoA/ROCK1/LIMK1 pathway by F-actin immunofluorescence staining and Western blot. Importantly, the BDP5290, an inhibitor of the RhoA/ROCK1/(LIM domain kinase 1) LIMK1 axis, reversed the effects of B7-H3 overexpression on actin filament accumulating, migration, and invasion of CRC cells.
Our study concluded that B7-H3 facilitated CRC cell actin filament accumulating, migration, and invasion through the RhoA/ROCK1/LIMK1 axis.
B7 同源物 3 蛋白（B7-H3）的异常表达已在多种癌症中被检测到，包括结直肠癌（CRC），并被认为调节 CRC 细胞的多种生物学功能。然而，其在 CRC 转移中的作用尚未确定。本研究旨在探索和揭示 B7-H3 通过何种机制促进 CRC 细胞迁移、侵袭和肌动蛋白细胞骨架。
通过免疫组化染色测定 CRC 肿瘤样本中 B7-H3 和 LIMK1 的表达。通过 Transwell 和 F-肌动蛋白免疫荧光染色实验来研究 B7-H3 在 CRC 细胞迁移、侵袭和肌动蛋白丝积累中的作用。使用 RNA-seq 和 Western blot 实验来研究分子机制。
B7-H3 在 CRC 组织中高表达，免疫组化染色显示其与 CRC 患者的预后不良呈正相关。迁移和侵袭实验表明，B7-H3 敲低显著抑制了 CRC 细胞的迁移和侵袭。B7-H3 过表达则产生相反的效果。此外，我们通过 F-肌动蛋白免疫荧光染色和 Western blot 确定，B7-H3 可以调节肌动蛋白细胞骨架和 RhoA/ROCK1/LIMK1 通路。重要的是，BDP5290 是 RhoA/ROCK1/(LIM 结构域激酶 1) LIMK1 轴的抑制剂，它逆转了 B7-H3 过表达对 CRC 细胞肌动蛋白丝积累、迁移和侵袭的影响。
我们的研究表明，B7-H3 通过 RhoA/ROCK1/LIMK1 轴促进 CRC 细胞肌动蛋白丝积累、迁移和侵袭。
