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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Basigin, Cell Communication, Cell Line, Tumor, Coculture Techniques, Humans, Leukemia, Monocytic, Acute, Mesenchymal Stem Cells, Neoplasm Invasiveness, Receptors, CXCR4.
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Does direct contact with bone marrow stromal cells promote the invasions of SHI-1 leukemia cells? Context: Interactions of tumor cells with the microenvironment were deemed to promote the tumor invasion and metastasis. CXC chemokine receptor 4 (CXCR4) and extracellular matrix metalloproteinase inducer (EMMPRIN) had reported to participate in this process. However the roles of bone marrow microenvironment in leukemic infiltration were not well investigated. A co-culture system between SHI-1 cells and bone marrow stromal cells (BMSCs) is used to simulate the interactions of leukemic cells with their microenvironment. The trans-matrigel invasion was used to detect the capability of SHI-1 cells invasion. The BMSCs and SHI-1 cells were mixed in a ratio of 1:10 and added to the millicell chamber coated with matrigel. Either the co-culture supernatant or the functional blocking peptide of CXCR4 and EMMPRIN were added to the trans-matrigel invasion system. The expressions of EMMPRIN in SHI-1 cells and BMSCs were detected by RT-PCR. The changes of the expression of matrix metalloproteinase-2, 9 (MMP-2, MMP-9), tissue inhibitor of metalloproteinase 2 (TIMP-2), and CXCR4 mRNA in SHI-1 cells were determined by real-time PCR. The concentration of stromal cell derived factor 1 (SDF-1) in serum free supernatant was measured by ELISA. Both SHI-1 cells and BMSCs express EMMPRIN. SHI-1 cells could hardly invade the matrigel membrane; the coculture supernatant did not induce the invasion of SHI-1 cells. When contacting directly with BMSCs, SHI-1 cells invaded to the lower chamber of millicell were significantly increased. The functional blocking peptide of CXCR4 and EMMPRIN could significantly inhibit the invasion triggered by BMSCs. When co-culturing with BMSCs, the expression of CXCR4, MMP-2, MMP-9 and TIMP-2 mRNA in SHI-1 cells were significantly elevated in company with a significantly higher level of SDF-1 in the co-cultured serum-free supernatant.
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The interactions of leukemic cells and BMSCs play important roles in leukemic cell infiltration. Final Decision: yes