RAP1B and esophageal squamous cell carcinoma: By inhibiting the expression of Rap1b, the proliferation and migration of hepatocellular carcinoma (HCC) [8], renal cell carcinoma (RCC) [9], esophageal squamous cell carcinoma (ESCC) [10], colorectal cancer cells (CRC) [11] and melanoma cells [12] had been inhibited.