RESUMO
Sulfated polysaccharides (Ac-SPSs) of Antrodia cinnamomea present anti-cancer activity. However, the anti-cancer mechanism of Ac-SPSs is not fully understood and remains largely unexplored. In this study, we identify an Ac-SPS with 7.9 kDa, noted ZnF3, and aim to examine the dual anti-cancer functions of ZnF3 on inhibiting cancer cells and activating macrophages. A biological study shows that ZnF3 inhibits lung cancer cells by inducing subG1 population and apoptosis. ZnF3 downregulates the expression of TGFß receptor in lung cancer cells. In parallel, ZnF3 activates macrophages via induction of TNF-α and IL-6 secretion, NO production and phagocytosis. ZnF3 activates AKT/mTOR pathway and induces M1 type macrophage polarization. Cancer cells co-cultured with ZnF3-stimulated macrophages, leading to inhibition of lung cancer cells. This study demonstrates that ZnF3 not only directly inhibits cancer cells but also activates macrophages-mediated cytotoxic effect on cancer cells. Moreover, ZnF3 may be a supplement for suppressing lung cancer cells.
Assuntos
Antrodia , Neoplasias Pulmonares , Humanos , Sulfatos/farmacologia , Polissacarídeos/farmacologia , Apoptose , Morte Celular , Neoplasias Pulmonares/tratamento farmacológico , MacrófagosRESUMO
BACKGROUND: Ling Zhi-8 (LZ-8) and GMI are two fungal immunomodulatory proteins (FIPs) with a similar structure and amino acid sequence and are respectively obtained from the medicinal mushroom Ganoderma lucidum and Ganoderma microsporum. They present the anti-cancer progression and metastasis. We previously demonstrated that LZ-8 reduces the tumor progression in lung cancer LLC1 cell-bearing mouse. However, it is unclear whether these FIPs induce changes in the protein expression profile in cancer cells and the mechanism for such a process is not defined. PURPOSE: This study determines the changes in the proteomic profile for tumor lesions of LLC1 cell-bearing mouse received with LZ-8 and the potential mechanism for FIPs in anti-lung cancer cells. METHODS: The proteomic profile of tumor lesions was determined using two-dimensional electrophoresis and a LTQ-OrbitrapXL mass spectrometer (LC-MS/MS). The biological processes and the signaling pathway enrichment analysis were performed using Ingenuity Pathway Analysis (IPA). The differentially expressed proteins were verified by Western blot. Cell viability was determined by MTT assay. Cell morphology was characterized using electron microscopy. Migration was detected using the Transwell assay. The apoptotic response was determined using Western blot and flow cytometry. RESULTS: Obtained results showed that 21 proteins in the tumor lesions exhibited differential (2-fold change, p < 0.05) expression between PBS and LZ-8 treatment groups. LZ-8-induced changes in the proteomic profile that may relate to protein degradation pathways. Specifically, three heat shock proteins (HSPs), HSP60, 70 and 90, were significantly downregulated in tumor lesions of LLC1-bearing mouse received with LZ-8. Both LZ-8 and GMI reduced the protein levels for these HSPs in lung cancer cells. Functional studies showed that they inhibited cell migration but effectively induced apoptotic response in LLC1 cells in vitro. In addition, the inhibitors of HSP60 and HSP70 effectively inhibited cell migration and decreased cell viability of LLC1 cells. CONCLUSIONS: LZ-8 induced changes in the proteomic profile of tumor lesions which may regulate the HSPs-related cell viability. Moreover, inhibition of HSPs may be related to the anti-lung cancer activity.