TTK contributes to tumor growth and metastasis of clear cell renal cell carcinoma by inducing cell proliferation and invasion

The aim of this study was to determine the expression levels of TTK in clear cell renal cell carcinoma (ccRCC) tissues and its possible link with the clinical pathologic characteristics and the prognosis of patients suffering this disease, and to further explore the potential role of TTK in the progression of ccRCC. Immunohistochemical (IHC) assays were performed to detect the expression levels of TTK in 112 samples of ccRCC tissues and corresponding non-tumor tissues. According to the results of IHC assays, patients were divided into TTK high expression and low expression group. Clinical analysis related to the clinical features (age, gender, T stage), and the potential link between TTK expression levels and clinical features were analyzed. In addition, the effects of TTK on the proliferation and invasion of ccRCC cells were detected through colony formation assay and transwell assays, respectively. The possible effects of TTK on tumor growth and metastasis were measured in mice. We found a high expression level of TTK in human ccRCC tissues from patients who received surgical treatment. We also found its expression level was obviously associated with clinical characteristics, such as T stage (p=0.008) and lymphatic metastasis (p=0.023). We further confirmed that knockdown of TTK suppressed cell proliferation and invasion in 2 types of ccRCC cells, HTB-47 and CRL-1932 cells. Furthermore, TTK contributes to tumor growth and metastasis of ccRCC in mice. We found that TTK affected the progression of ccRCC and further mechanically confirmed it could be a novel therapeutic target for ccRCC treatment.