Abstract
Notch 1 is a key component of the Notch pathway, which performs a crucial role in clear cell renal cell carcinoma (CCRCC) development. The present study aimed to investigate whether Notch 1 could serve as a potential target for CCRCC treatment. Firstly, an association analysis was performed using 52 CCRCC cases and 30 normal controls. The results indicated that Notch 1 protein expression in renal tissues was closely associated with the incidence of CCRCC. In addition, higher Notch 1 expression in CCRCC tissues was positively associated with higher tumor-node-metastasis stage and Fuhrman grade, in addition to larger tumor size. Subsequently, an in vitro study was conducted to examine the biological functions of Notch 1 in CCRCC 786-O cells through inhibiting the Notch 1 expression with Notch 1-specific small interfering RNA (siRNA). As a result, the inhibition of Notch 1 expression by increasing concentrations of Notch 1-specific siRNA dose-dependently decreased cell proliferation and increased cell apoptosis in 786-O cells. Furthermore, B-cell lymphoma-2 and procaspase-3 expression exhibited a dose-dependent decrease accompanied with a dose-dependent inactivation of the Akt/mammalian target of rapamycin (mTOR) signaling pathway in Notch 1 siRNA-treated 786-O cells. These findings demonstrated that Notch 1 was associated with CCRCC carcinogenesis and progression, the underlying mechanism of which was that Notch 1 acted as an activator for cell proliferation and a suppressor for cell apoptosis through the Akt/mTOR signaling-dependent pathway in CCRCC. In conclusion, the present study confirmed that Notch 1 is a valuable target against cell survival and proliferation in CCRCC treatment.