ABSTRACT
Herein, we found that serum concentration of superoxide dismutase 3 (SOD3) was significantly reduced in children with mycoplasma pneumonia (MP) infection. To study the roles of SOD3 in inflammatory regulation of MP infection, human A549 type II alveolar epithelial cells were stimulated with 107 CCU/ml of MP to build MP infection in vitro. Secretion of pro-inflammatory cytokine interleukin (IL)-8 and tumor necrosis factor (TNF)-α were measured via enzyme-linked immunosorbent assay (ELISA) to assess the inflammatory response of A549 cells. Levofloxacin (LVFX) was used as an anti-inflammatory drug while recombinant TNF-α was used as an inflammatory promotor in MP-infected cells. Transcriptional activity of nuclear factor (NF)-κB was assessed by detecting protein levels of nuclear NF-κB and cytoplasm NF-κB using Western blot analysis. Our data suggested that the expression of SOD3 mRNA and protein, as well as content of SOD3 in cultured supernatant, were time-dependently inhibited in MP-infected A549 cells. However, lentiviruses-mediated SOD3 overexpression alleviated inflammatory response of MP-infected A549 cells, and prevented the unclear translocation of NF-κB, as evidenced by obviously reducing the production of IL-8 and TNF-α in cell cultured supernatant, as well as decreasing nuclear NF-κB while increasing cytoplasm NF-κB. Inspiringly, SOD3 overexpression induced anti-inflammatory effect and the inactivation of NF-κB was similar to that of 2 lg/ml of LVFX, but reversed by additional TNF-α treatment. Therefore, we can conclude that transcriptional activity of NF-jB was the underlying mechanism, by which SOD3 regulated inflammatory response in MP infection in vitro.
Subject(s)
Inflammation/genetics , Interleukin-8/genetics , Pneumonia, Mycoplasma/genetics , Superoxide Dismutase/genetics , Tumor Necrosis Factor-alpha/genetics , A549 Cells , Cell Nucleus/drug effects , Cell Nucleus/genetics , Child , Humans , Inflammation/drug therapy , Inflammation/microbiology , Levofloxacin/pharmacology , Lipopolysaccharides/pharmacology , Mycoplasma pneumoniae/pathogenicity , Pneumonia, Mycoplasma/microbiology , Pneumonia, Mycoplasma/pathology , RNA, Messenger/geneticsABSTRACT
OBJECTIVE: To evaluate in vitro antitumor effects of chemotherapeutic drugs, and investgate the relationship with expression of hTERT mRNA in human gastric cancer tissues. METHODS: Fresh samples of gastric cancer obtained from operation room were prepared to single-cell suspension (3 x 10(5) to 5 x 10(5) cells ml(-1)) and were separately exposed to taxol (TAX), cisplatin (CDDP), 5-fluorouracil (5-Fu), adriamycin (ADM), mitomycin (MMC) for 48 hours. Metabolic activity and inhibitory rate of the cells were determined by trypan blue exclusion and MTT assay. Expression of hTERT mRNA was detected by in situ hybridization (ISH). RESULTS: The inhibition rate of cancer cells exposed to chemotherapeutic drugs was different, and that of TAX, CDDP, 5-Fu was significantly higher than that of ADM and MMC. The positive rate of hTERT mRNA expression was 90.0% (54/60) and positive cells showed resistance to 5-Fu and ADM. CONCLUSION: Overexpression of hTERT mRNA may contribute to primary drug-resistance of tumors. Chemosensitivity tests by MTT assay may contribute to prediction of effectness in applying chemotherapeutic drugs and identify drug-resistant cases.
