RESUMO
The aim of the present study was to analyze the role of leucinerich repeatcontaining Gprotein coupled receptor 6 (Lgr6) in the proliferation and invasion of colorectal cancer (CRC) cells, and to investigate its possible mechanisms. The expression of Lgr6 in CRC tissues was observed by real timequantitative polymerase chain reaction and western blotting. Then cell viability, apoptosis and cell invasion was measured by MTT, flow cytometry or MatrigelTranswell system, respectively in CRC cells after transfected with Lgr6 siRNA or Lgr6 vector. Furthermore, the expression of apoptosisassociated protein and PI3K/AKT signaling (phosphorylatedPI3K, phosphorylatedAKT, tPI3K, tAKT) were measured by realtime PCR/or western blot analysis. The results demonstrated that the level of Lgr6 was higher in CRC tissues than that in adjacent tissues, and Lgr6 overexpression increased CRC proliferation, and invasion of CRC cells in vitro. Notably, suppressing the expression of Lgr6 in CRC cells increased the expression of Bcell lymphoma-2 (Bcl2)associated X protein and caspase3, but decreased the expression of Bcl2 at the mRNA and protein levels. Lgr6 also had the ability to regulate the phosphoinositide 3kinase/AKT signaling pathway. It was concluded that Lgr6 has a tumorpromoting role in the development of CRC, and may serve as a potential diagnostic and prognostic biomarker for the disease.