Kallikrein 12 downregulation reduces AGS gastric cancer cell proliferation and migration.

Abnormal expression of the kallikrein (KLK) family of serine proteases closely correlates with onset, progression, and prognosis of endocrine gland-related malignant tumors. The aim of this study was to evaluate how downregulation of KLK12 influenced cell cycle and proliferation of the AGS gastric cancer cell line. KLK12 was detected by western blot in GES-1 normal gastric epithelial and AGS cells. AGS cells were transfected with KLK12 siRNA, a negative control siRNA, or subjected to a mock transfection, following which, we assessed mRNA and protein levels, cell proliferation, cell migration, and cell cycle progression. We found that KLK12 levels were significantly higher in AGS cells than in GES-1 cells. Transfection of AGS cells with KLK12 siRNA led to downregulation of KLK12 mRNA and protein expression, reduced cell proliferation (0.47 ± 0.03 vs 0.92 ± 0.04, P < 0.01), and lower cell counts (3.92 ± 0.25 x 105 vs 5.47 ± 0.50 x 105, P < 0.01) with respect to the negative control. We observed that KLK12 siRNA increased the number of AGS cells in G0/G1 and reduced those in S phase. Furthermore, downregulation of KLK12 in AGS cells decreased their ability to penetrate the membrane in a migration assay (P < 0.05). In conclusion, KLK12 siRNA inhibited the proliferation and migration of AGS gastric cancer cells and caused their arrest in the G0/G1 phase of the cell cycle.