ABSTRACT
To explore the effect of lycorine in inducing apoptosis of pulmonary carcinoma cell A549 and its mechanism. In the study, pulmonary carcinoma cell A549 were taken as the experimental subject and processed with different concentrations of lycorine (0, 0.5, 1.0, 2.0, 4.0 and 8.0 μmol x L(-1)). The MTT method was used to observe the cell proliferation. The apoptosis rate of A549 cells was determined by Annexin FITC/PI double staining. The microplate reader was used to detect the activities of Bcl-2, Bax and p53. The changes in mitochondrial membrane potential were measured by the flow cytometry. The expressions of apoptosis-related factors Bcl-2, Bax, p53 and Survivin were determined by Real-time PCR. The results showed that lycorine significantly inhibited the proliferation of A549 cells (P < 0.05), induced the apoptosis on A549 cells (P < 0.05), increased the activities of Bax and p53, reduced Bcl-2 activity and mitochondrial membrane potential, and notably changed the gene expressions of Bcl-2, Bax, p53 and Survivin (P < 0.05). In conclusion, lycorine can induce the apoptosis of A549 cells and be applied to treat pulmonary carcinoma. Its mechanism may be related to the activation of relevant factors in Bcl-2 signaling pathway.
Subject(s)
Humans , Amaryllidaceae Alkaloids , Pharmacology , Antineoplastic Agents, Phytogenic , Pharmacology , Apoptosis , Carcinoma , Drug Therapy , Genetics , Metabolism , Cell Line, Tumor , Cell Proliferation , Drugs, Chinese Herbal , Pharmacology , Lung Neoplasms , Drug Therapy , Genetics , Metabolism , Phenanthridines , Pharmacology , Proto-Oncogene Proteins c-bcl-2 , Genetics , Metabolism , Signal Transduction , Tumor Suppressor Protein p53 , Genetics , Metabolism , bcl-2-Associated X Protein , Genetics , MetabolismABSTRACT
Objective To observe the effects of hypoxia on the expression of connective tissue growth factor(CTGF)and matrix metalloproteinase 9(MMP-9)in lung fibroblasts at different time points.Methods Fibroblasts were cultured at hypoxic condition 0,1.5,3,6,12 h respectively.CTGF mRNA and MMP-9 mRNA level were detected in each group by reverse transcription-polymerase chain reaction(RT-PCR).The concen- tration of CTGF and MMP-9 protein in fibroblasts supernatant were determined using enzyme-linked im- munosorbent assay(ELISA).Results Hypoxia stimulated fibroblasts increased the level of CTGF mRNA with- in 1.5 h,and the levels remained at a plateau up to 6 h,and then decreased by 12 h.The level of MMP-9 mRNA increased significantly within 3 h,and the levels kept the trend for increasing.ELISA revealed that the levels of both CTGF and MMP-9 protein/cell in medium conditioned by fibroblasts exposed to hypoxia were maximal at 12 h.The level of MMP in the CTGF-Ab treated groups was significantly decreased compared to the untreated groups.Conclusions These findings suggest that hypoxia stimulates fibroblasts to release CTGF as a mitogen factor,which initiates the fibrosis cascade and airway remodeling by regulating the balance of extracellular ma- trix synthesis and degradation via MMP-9 which is secreted by fibroblast cells in response to CTGF.