Kaempferol suppresses human gastric cancer SNU- 216 cell proliferation, promotes cell autophagy, but has no influence on cell apoptosis

Abstract

Gastric cancer remains a serious threat to human health worldwide. Kaempferol is a plant-derived flavonoid compound with a wide range of pharmacological activities. This study aimed to investigate the effects of kaempferol on gastric cancer SNU-216 cell proliferation, apoptosis, and autophagy, as well as underlying potential mechanisms. Viability, proliferation, and apoptosis of SNU-216 cells after kaempferol treatment were evaluated using cell counting kit-8 assay, 5-btomo-20-deoxyuridine incorporation assay, and annexin V-FITC/PI staining, respectively. Quantitative reverse transcription PCR was performed to measure the mRNA expressions of cyclin D1 and microRNA-181a (miR-181a) in SNU-216 cells. Cell transfection was used to down-regulate the expression of miR-181a. The protein expression levels of cyclin D1, bcl-2, bax, caspase 3, caspase 9, autophagy-related gene 7, microtubule-associated protein 1 light chain 3-I (LC3-I), LC3-II, Beclin 1, p62, mitogen-activated protein kinase (MAPK), extracellular regulated protein kinases (ERK), and phosphatidylinositol 3 kinase (PI3K) in SNU-216 cells were detected using western blotting. Results showed that kaempferol significantly suppressed SNU-216 cell viability and proliferation but had no influence on cell apoptosis. Further results suggested that kaempferol significantly induced SNU-216 cell autophagy. The expression of miR-181a in SNU-216 cells after kaempferol treatment was enhanced. Kaempferol significantly inactivated MAPK/ERK and PI3K pathways in SNU-216 cells. Suppression of miR-181a significantly reversed the kaempferol-induced MAPK/ERK and PI3K pathways inactivation in SNU-216 cells. This research demonstrated that kaempferol suppressed proliferation and promoted autophagy of human gastric cancer SNU-216 cells by up-regulating miR-181a and inactivating MAPK/ERK and PI3K pathways.