GMI, a Ganoderma Immunomodulatory Protein, Down-regulates Tumor Necrosis Factor α-Induced Expression of Matrix Metalloproteinase 9 via NF-κB Pathway in Human Alveolar Epithelial A549 Cells

Abstract

Matrix metalloproteinase 9 (MMP-9) has been implicated in airway injury in chronic obstructive pulmonary disease (COPD), lung inflammation, and lung cancer and plays a major role in tumor necrosis factor-α (TNF-α)-stimulated tumor invasion and lung inflammation. MMP-9 activity is promoted by the pro-inflammatory cytokine TNF-α. GMI, cloned from Ganoderma microsporum and purified, is one of the recombinant fungal immunomodulatory proteins. To understand the molecular mechanisms involved in the suppression of TNF-α-mediated tumor invasion and inflammation, GMI modulation of this pathway was investigated in human alveolar epithelial A549 cells in this study. GMI exhibited an inhibitory effect on TNF-α-induced invasion, with GMI treatment and TNF-α exposure presenting the most anti-invasive properties on Boyden chamber assay. GMI reduced TNF-α-induced MMP-9 activities on gelatin zymography assay through inhibition of MMP-9 transcriptional activity. RT-PCR and MMP-9 promoter luciferase analysis revealed that GMI inhibits the transcription of MMP-9 mRNA. Moreover, in vitro and in vivo binding experiments, an electrophoretic mobility shift assay (EMSA), and chromatin immunoprecipitation assay (ChIP) demonstrated that GMI suppresses DNA binding of nuclear factor (NF)-κB transcription factors to MMP-9 promoter. Western blot analysis indicated that GMI blocks the phosphorylation and degradation of IκBα, which in turn leads to suppression of the phosphorylation and nuclear translocation of p65. Thus, overall, our results indicated that GMI mediates antitumor invasion and anti-inflammatory effects through modulation of NF-κB/MMP-9 pathways.

Recombinant Expression of a Novel Fungal Immunomodulatory Protein with Human Tumor Cell Antiproliferative Activity from Nectria haematococca

“…Previous studies demonstrated that rLZ-8 and rFIP-gts inhibited cell proliferation by increasing G1 arrest [33,34,35,36], rFIP-fve suppressed A549 cell proliferation via the p53 activation pathway [37] and FIP-gmi inhibited metastatic ability regulated by epidermal growth factor in A549 cells [38]. These observations suggest that FIPs can be therapeutic.…”

Berberine Reverses Epithelial-to-Mesenchymal Transition and Inhibits Metastasis and Tumor-Induced Angiogenesis in Human Cervical Cancer Cells

“…Specific binding was confirmed with a 200-fold excess of unlabeled probe as a specific competitor. Gel shifts were visualized with a streptavidin-HRP followed by chemiluminescent detection (Lin et al, 2010).…”

“…After incubation with berberine, cells were collected and disrupted by the Luciferase Assay System (Promega, San Diego, CA). Firefly luciferase activities were standardized for b-galactosidase activity (Lin et al, 2010).…”

Proteome Exploration to Provide a Resource for the Investigation of Ganoderma lucidum

“…The examples include Fip-vvo from Volvariella volvacea [43], GMI from Ganoderma microsporum [44, 45], IPAF from Anoectochilus formosanus [46], AAL and AAL-2 from Agrocybe aegerita [47, 48], and immunomodulatory protein LZ-8 from G . lucidum [49, 50].…”