MicroRNA-193b acts as a tumor suppressor in colon cancer progression via targeting RAB22A

To explore microRNA (miR)-193b expression and its potential role in colon cancer, reverse transcription-quantitative polymerase chain reaction was performed to detect the miR-193b expression levels in 62 colon cancer tissues and normal adjacent tissues. The miR-193b-overexpressed cell line SW620 was used to study the role of miR-193b in colon cancer. Subsequently, a Transwell assay and cell cycle assay were performed to observe the functional cell changes in the in vitro expression levels of miR-193b. Results indicated that miR-193b expression levels were significantly decreased in colon cancer tissues compared with adjacent normal tissue (P<0.001) and the expression of miR-193b was significantly correlated with TNM staging (P=0.03) and lymph node invasion (P=0.007). Furthermore, overexpression of miR-193b significantly decreased colon cancer cell cycle progression and its migration ability. In addition, the present findings suggested that the increased expression of miR-193b by RAB22A, inhibited downstream proteins involved in the Ras signaling pathway, including the Ras and extracellular signal-related kinase which may inhibit cancer proliferation and migration. In conclusion, the aim was to clarify the association of miR-193b expression with colon cancer, and to explore the mechanism of miR-193b in colon cancer proliferation and cell migration. The preliminary findings revealed that miR-193b may have an important role in the process in colon cancer cell cycle and migration by the RAB22A-Ras signaling pathway, thus providing a theoretical basis for miR-193b as a potential molecular target for colon cancer treatment.