Rho-associated kinase (ROCK)-associated proteins and genes-encoded proteins upregulated in lung squamous cell carcinoma (LUSC).

BACKGROUND: The Rho-associated kinase (ROCK) signaling pathway was reported to be overexpressed in cancer, as it promotes multiple hallmarks of cancer. However, the characterization of ROCK signaling pathway expression in dual-stage carcinogenesis of lung squamous cell carcinoma (LUSC) remains unclear. Therefore, this study aims to evaluate ROCK signaling pathway expression during LUSC progression in vivo. METHODS: Female BALB/c mice were treated with N-nitroso-tris-chloroethylurea (NTCU) to induce pre-malignant and malignant LUSC stages. The lung tissues were subjected to immunohistochemistry and Western blot for ROCK-associated protein expression analysis. Then, differentially expressed genes (DEGs) analysis from two expression profiling datasets: GSE30219 and GSE31446, was performed to determine the mRNA expression of ROCK-associated proteins in human LUSC. Protein-protein interaction (PPI) network (analysed via Cytoscape) and correlation analysis (analysed via Gene Expression Profiling Interactive Analysis 2; GEPIA2) were also conducted to identify the relationships between each ROCK-associated protein. RESULTS: This study found a significantly higher expression (p-value<0.05) of ROCK-associated proteins such as pFAK, RhoABC, ROCK1, ROCK2, and pMLC during LUSC progression via IHC and Western blot assays. Notably, RhoA, RhoB, and pMLC (MYL9) mRNA were significantly upregulated in human LUSC. The PPI and correlation analysis identified RhoA, ROCK1, and ROCK2 as highly correlated ROCK-associated genes encoded proteins in LUSC. CONCLUSION: Increased ROCK-associated proteins and genes expression in dual-stage carcinogenesis of LUSC may reflect their essential role in cancer growth. Bioinformatic analysis results verify the importance of ROCK signaling pathways in LUSC growth, making them promising targets for future LUSC treatment.