CRISPR/Cas9-mediated Knockout of LYVE1 In Human Tongue Cancer Cells Reveals Transcriptomic Changes in Metastasis-associated Pathways.

BACKGROUND/AIM: Tongue squamous cell carcinoma (TSCC), a highly aggressive subtype of head and neck cancers, is characterized by frequent lymphatic metastasis and poor prognosis. Recently, we showed that lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) is involved in TSCC progression, yet the underlying molecular mechanisms remain unclear. MATERIALS AND METHODS: CRISPR/Cas9 gene editing was employed to generate LYVE1 knockout (KO) TSCC cell lines. Single-cell clones were isolated, screened, and validated through sequencing and Inference of CRISPR Edits (ICE) analysis and qRT-PCR. RNA sequencing was performed on LYVE1 KO and wild-type (WT) cells to identify differentially expressed genes (DEGs). Bioinformatic analyses, including Gene Ontology (GO) enrichment and protein-protein interaction (PPI) network mapping, were conducted to explore affected pathways. Finally, network topology was examined using NetworkAnalyzer and cytoHubba plugins. RESULTS: Transcriptomic analysis revealed significant down-regulation of pro-metastatic pathways, including epithelial-mesenchymal transition (EMT), extracellular matrix remodeling, and immune modulation. DEG analysis identified 263 genes, with key down-regulated targets such as WNT5A, TGFB2, and MMP2, and up-regulation of tumor-suppressive genes including PTGS2. GO and PPI analyses highlighted LYVE1's pivotal role in regulating cell adhesion, migration, and immune response. CONCLUSION: LYVE1 KO reduces TSCC invasive potential by disrupting EMT and tumor-stroma interactions, aligning with previous experimental findings. These results suggest LYVE1 as a critical driver of metastasis, highlighting its potential as a therapeutic target.