Abstract:

Background and purpose: The interaction of CXC motif chemokine receptor (CXCR) on the cell surface of multiple myeloma (MM) with chemokines in the bone marrow microenvironment is involved in proliferation, survival and extramedullary invasion of MM cells. Sinomenine derivative YL064 exerts its biological effects by targeting intracellular signaling regulators in MM cells. This study aimed to explore possible modulating and biological effects of sinomenine derivative YL064 on CXCR3 in MM cells. Methods: The MM cell lines H929 and MM1.S were used as in vitro models. H929-OE and MM1.S-OE cells with stable overexpression of CXCR3 were constructed with lentivirus vector. The effects of CXCR3 on clonal formation and migration of MM cells were detected by clone spot formation and transwell migration assay. Meanwhile, flow cytometry was used to analyze apoptotic rates of H929, H929-OE, MM1.S and MM1.S-OE cells treated with different concentrations of YL064. Furthermore, real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) and Western blot assay were applied to detect expression levels of CXCR3 and its downstream signal regulators extracellular regulated protein kinase (ERK) and p-protein kinase B (p-AKT) in H929 and MM1.S cells before and after the treatment with YL064. Results: The clonal formation rates of H929-OE and MM1.S-OE cells with CXCR3 overexpression reached to 81.33%±5.79% and 73.00%±4.90%, which were significantly higher compared with H929 (58.33%±3.30%) and MM1.S cells (41.00%±3.14%). The migration proportion of H929-OE and MM1.S-OE cells were 7.90%±0.81% and 23.00%±1.63%, which were significantly higher compared with H929 (4.63%±0.37%) and MM1.S cells (14.63%±1.04%). After treatment with YL064, the apoptotic rates of H929-OE and MM1.S-OE cells were 29.80%±0.30% and 14.20%±0.26%, which were lower than those of H929 (33.40%±0.25%) and MM1.S cells (21.60%±0.21%). It was also shown that YL064 could reduce clonal formation and migration, inhibit CXCR3 gene transcription and downregulate expressions of CXCR3, ERK and AKT in H929 and MM1.S cells. Conclusions: CXCR3 might promote proliferation and invasion of MM cells. Sinomenine derivative YL064 could downregulate expressions of CXCR3 and its downstream signal regulators in MM cells, reduce abilities of clonal formation and migration, and induce apoptosis.

Key words: Multiple myeloma, Sinomenine derivative, CXCR3