[Expression of LIM and SH3 protein 1 in renal clear cell carcinoma and its effects on invasion and migration of renal clear cell carcinoma 786-O cells].

Objective: To investigate the expression of LIM and SH3 protein 1 (LASP1) in renal cell carcinoma and its significance in the invasion and migration of renal clear cell carcinoma 786-O cell line. Methods: The expression level of LASP1 in 41 cases of renal cell carcinoma tissues and normal renal tissues was analyzed by immunohistochemistry. The relationship between the expression level of LASP1 and clinical characteristics was further analyzed. Expression of LASP1 in 10 cases of tumor tissues with or without lymph node metastasis was analyzed by Western blot. Furthermore, small interfering RNA (siRNA) targeting LASP1 was constructed and transfected into 786-O cells to downregulate LASP1 expression. The interference effect of LASP1 siRNA on LASP1 protein and the expression of related proteins in epithelial mesenchymal transition (EMT) pathway were detected by Western blot. The effects of LASP1 knockdown on cell proliferation, migration and invasion and gene expression were then assessed using CCK8 assay, transwell cell migration system and western blot analysis, respectively. Results: The positive rate of LASP1 expression in renal clear cell carcinoma tissues was 90.2% (37/41), which was significantly higher than that in the adjacent tissues (29.3%, P=0.002). The expression of LASP1 in renal cell carcinoma was positively correlated with lymph node metastasis and TNM stage of renal cell carcinoma (P<0.05). The results of Western blot showed that LASP1 (0.696±0.053) was highly expressed in renal cell carcinoma (1.459±0.628), especially in cases with lymph node metastasis (2.692±0.186, P<0.05). The LASP1 siRNA remarkably down-regulated the expression of LASP1 protein in 786-O cells. The abilities of proliferation, invasion and migration of 786-O cells were decreased significantly in the LASP1 siRNA groups.The relative expression of E-cadherin protein in the siRNA group (0.848±0.020) was significantly higher than those in the siRNA-NC group (0.671±0.018) and control group (0.691±0.037, P<0.05). The relative expression of N-cadherin protein in the siRNA group (0.449±0.047) was significantly lower than those in the siRNA-NC group (0.613±0.018) and control group (0.633±0.045, P<0.05). The relative expression of vimentin protein in the siRNA group (0.477±0.029) was significantly lower than those in the siRNA-NC group (0.598±0.069) and control group (0.633±0.045, P<0.05 for both). Conclusions: LASP1 is highly expressed in renal clear cell carcinoma, which is closely related to the development of the cancer. The effects of LASP1 on the invasion and migration of 786-O cells and lymph node metastasis may be related to the EMT.