ABSTRACT
ObjectiveTo investigate the efficacy and mechanism of berberine hydrochloride （BBH） against lung cancer cells through the mevalonate （MVA） pathway. MethodHuman lung cancer A549 cells and mouse Lewis lung carcinoma （LLC） cells were used as research subjects. Cell proliferation and cell counting kit-8 （CCK-8） assay were performed to detect the inhibitory effect of BBH （10， 20， 30， 40， 50 μmol·L-1） on the proliferation of the two kinds of cells （48 h）. Then cell scratch assay was used to explore the influence of BBH （40 μmol·L-1） on the migration of A549 and LLC cells （24， 48 h）， and colony formation assay was conducted to compare the colony formation ability of the cells under different concentrations of BBH （10， 20， 40 μmol·L-1）. Moreover， the effects of BBH （40 μmol·L-1） on the content of acetyl-coenzyme A （A-CoA） and total cholesterol （TC） in A549 and LLC cells were determined by kit assay. AutoDock Vina was used for the dock of BBH and MVA pathway regulatory protein， sterol regulatory element-binding protein 2 （SREBP2）. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was used to observe the effects of BBH （40 μmol·L-1） on the mRNA expression of nine genes related to the MVA pathway in A549 and LLC cells： hydroxymethylglutaryl-CoA synthase 1 （HMGCS1）， hydroxymethylglutaryl-CoA Reductase （HMGCR）， mevalonate kinase （MVK）， phosphomevalonate kinase （PMVK）， mevalonate 5-pyrophosphate decarboxylase （MVD）， farnesyl diphosphate synthase （FDPS）， squalene epoxidase （SQLE）， farnesyl-diphosphate farnesyltransferase 1 （FDFT1）， and geranylgeranyl diphosphate synthase 1 （GGPS1）. Western blot was performed to clarify the effects of BBH （40 μmol·L-1） on the expression of three key proteins of the MVA pathway： HMGCS1， HMGCR， and FDFT1. The Cancer Genome Atlas （TCGA） database was searched to analyze the relationship between HMGCS1， HMGCR， FDFT1 and transcription gene SREBF2 in non-small cell lung cancer （NSCLC）. ResultCompared with the conditions in the control group， the proliferation， migration， and colony formation of A549 and LLC cells in the BBH group were decreased （P<0.01）， while the cell apoptosis rate was increased （P<0.01）. Molecular docking showed that BBH had good binding activity with SREBP2. In addition， the content of A-CoA and TC of the MVA pathway was reduced （P<0.01）. BBH down-regulated the mRNA expression of HMGCS1， HMGCR， MVK， PMVK， MVD， FDPS， SQLE， FDFT1， and GGPS1 in A549 and LLC cells （P<0.01）， and lowered the levels of HMGCS1， HMGCR， and FDFT1 proteins （P<0.05， P<0.01）. In NSCLC patients， HMGCS1， HMGCR， and FDFT1 were highly correlated with SREBF2 （R=0.54， R=0.57， and R=0.48）. ConclusionBBH can inhibit the proliferation， migration， and colony formation of A549 and LLC cells and promote cell apoptosis， which may be related to the regulation of MVA pathway by BBH binding to SREBP2.