ABSTRACT
@# Objective: To investigate the effects of tumor-associated macrophages (TAM) on proliferation, migration, invation and apoptosis of gastric cancer MGC-803 cells and the possible mechanisms. Methods: Human monocyte THP-1 was cultured in vitro. After being added with PMA and IL-4, the levels of interleukin-12 (IL-12) and interleukin-10 (IL-10) in cell supernatant were detected by enzyme-linked immunosorbent assay (ELISA). MGC-803 cells at logarithmic phase and M2-type TAM cells were divided into single cell culture group, non-contact co-culture group and contact co-culture group according to different culture methods. MTT assay was used to detect the proliferation of MGC-803 cells, Transwell assay was used to detect cell migration and invasion, andAnnexin V-FITC/ PI staining flow cytometry was used to examine the apoptosis and cell cycle changes of MGC-803 cells; In addition, the mRNAand protein expressions of matrix metalloproteinase-9 (MMP-9) and MMP-2 were detected by Real-time fluorescence quantitative PCR (qPCR) and Western blotting. Results: Compared with PMA group, the level of IL-12 in cell supernatant of PMA+IL-4 group decreased significantly while the level of IL-10 increased significantly (all P<0.05), indicating THP-1 cells were successfully induced to differentiate into M2-type TAM. Compared with the single cell culture group, the non-contact co-culture group and the contact co-culture group exhibited: (1) significantly increased proliferation rate of MGC-803 cells (P<0.05)； (2) increased number of migrated and invaded cells (all P < 0.05)； (3) significantly decreased apoptotic rate (P<0.05)； (4) increased proportion of S, G2 phase cells and decreased proportion of G1 phase cells (all P<0.05)；and (5) significantly increased mRNA and protein expressions of MMP-9 and MMP-2 (all P<0.05). Conclusion: TAM can promote the proliferation, migration and invasion of gastric cancer MGC-803 cells, relieve G1 phase arrest and reduce cell apoptosis, which may be related to the up-regulation of MMP-9 and MMP-2 expression in gastric cancer cells.
ABSTRACT
BACKGROUND: Cholecyst cholesterol lithiasis is a common disease of the digestive system; however, the cause of lithogenesis is still unclear. Although bile salt export pump (BSEP), multidrug resistance protein 2 (MRP2), and multiple drug resistance 3 (MDR3) are 3 well-known transporting proteins, their effect on lithogenesis has not been elucidated. This study was undertaken to examine the relationship between BSEP, MRP2, MDR3, and cholesterol calculus formation. METHODS: Liver tissue specimens were taken from 20 patients with cholesterol calculus and from 10 patients with normal liver. mRNA and protein expressions of BSEP, MRP2, and MDR3 were determined by reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot, respectively. This study was approved by the ethics committee of China Medical University and informed consent was obtained from all patients. RESULTS: mRNA and protein expressions of BSEP, MRP2, and MDR3 were significantly down-regulated in the liver tissue of the patients with cholesterol calculus compared with normal liver tissue of the controls. CONCLUSION: The down-regulation of BSEP, MRP2, and MDR3 may be correlated with the formation of cholesterol calculus.
