AIM:To explore the expression of RhoC in oral squamous cell carcinoma(OSCC)and its effects on the malignant biological behavior of OSCC cells.METHODS:The UALCAN and K-M plotter databases,alongside tis-sue sample analyses,facilitated understanding RhoC expression in cancer and its links to clinicopathological traits.Two small interfering RNAs(RhoC-siRNA)were constructed according to the RhoC gene sequence.The mRNA and protein ex-pression levels of RhoC in OSCC cells were determined.The protein levels of FAK,p-FAK,MAPK,p-MAPK,matrix me-talloproteinase-2(MMP-2)and MMP-9 were also examined by Western blot.Furthermore,the invasion and migration of OSCC cells were analyzed by Transwell assay and scratch test.Finally,the pulmonary metastasis model of nude mice was established.RESULTS:The results of the databases showed that RhoC was highly expressed in OSCC tissues,which was closely related to pathological stage,pathological grade and lymph node metastasis,but not significantly related to the sur-vival rate of patients.Furthermore,compared with paracancer tissues,the mRNA and protein expression levels of RhoC were increased in OSCC tissues(P<0.01).Silencing of RhoC prominently reduced the migration and invasion of OSCC cells as well as the protein levels of p-FAK,p-MAPK,MMP2 and MMP9(P<0.05).The protein levels of MAPK and FAK were unchanged(P>0.05).The fluorescence intensity of the experimental group was significantly lower than that of the control group,and the results of HE staining showed that the number of lung nodules in the experimental group was sig-nificantly reduced(P<0.05).CONCLUSION:RhoC can effectively influence the migration and invasion of OSCC cells,and its potential mechanism may be related to FAK/MAPK/MMPs signaling pathway.

Objective: To explore whether RhoA plays a role in the migration and invasion of the salivary adenoid cystic carcinoma cell lines SACC-LM and SACC-83. Methods: Total RNA and total protein were extracted from 20 salivary adenoid cystic carcinoma (SACC) and normal adjacent tissues frozen in liquid nitrogen to detect RhoA expression. RhoA-siRNA was constructed to transfect two cell lines (SACC-LM and SACC-83) for cytological experiments. The research included an experimental group (RhoA-siRNA transfection), negative control group (siRNA-NC transfection) and blank group by transient transfection with liposomes. Expression of RhoA mRNA and protein as well as the protein expression of biomarkers of epithelial-mesenchymal transition (EMT) were analyzed, including E-cadherin, N-cadherin, and Vimentin. Furthermore, the changes in invasion and migration of cells in each group were analyzed by comparing the number of transmembrane cells in the Transwell assay and the results of the scratch test. Results: Compared with normal adjacent tissues, RhoA protein and mRNA levels increased in SACC tissues. Compared with the control group, the relative expression levels of RhoA mRNA and protein decreased (P < 0.01), the relative expression levels of E-cadherin protein increased, and the relative expression levels of N-cadherin and vimentin protein increased in the experimental group (P < 0.01). Additionally, the trial results revealed that RhoA knockdown restrained cell migration and invasion (P < 0.01). Conclusion RhoA expression increased in SACC tissue. Silencing RhoA in vitro could effectively restrain cell migration and invasion in SACC-LM and SACC-83 cells through the regulation of EMT signaling pathways.