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Background: As one of the malignant tumors most often affecting children and young adults, Ewing sarcoma (ES) is characterized by early metastasis contributing to unfavorable prognosis. However, the molecular mechanisms responsible for ES metastasis remain poorly understood. In this study, we aimed to explore whether Wnt5a, a putative pro-metastatic factor, plays a role in ES metastasis. Methods: Expression of Wnt5a and CXCR4 was determined by real-time PCR or Western blot in 15 ES specimens and 4 ES cell lines, A-673, RD-ES, SK-N-MC and SK-ES-1. Expression of Wnt antagonists, SFRP1, SFRP2 and SFRP5, and some components in noncanonical Wnt pathway (p-JNK, p-cJUN and p-PKC) was also analyzed in this study. Methylation status of SFRP1, SFRP2 and SFRP5 was detected by Methylation-specific PCR (MSP). Wnt5a shRNA and pcDNA3.1 SFRP5 vector were used to abrogate Wnt5a expression and overexpress SFRP5 in ES cells, respectively. Results: Wnt5a expression was positively correlated with CXCR4 expression in ES specimens. Levels of both Wnt5a mRNA and CXCR4 mRNA were significantly higher in specimens from ES patients with metastasis at diagnosis compared with specimens from those without metastasis. Recombinant Wnt5a enhanced CXCR4 expression in ES cells, which was accompanied by increased ES cell migration, whereas Wnt5a shRNA has opposite effects. SFRP5 was methylated and silenced in ES cells, and both recombinant SFRP5 and pcDNA3.1 SFRP5 vector suppressed CXCR4 expression as well as ES cell migration. Wnt5a shRNA and recombinant SFRP5 inhibited phosphorylation of JNK and cJUN, and JNK inhibitor also reduced CXCR4 expression and cell migration in ES cells. Conclusions: Wnt5a increases ES cell migration via upregulating CXCR4 expression in the absence of Wnt antagonist SFRP5, suggesting that Wnt5a overexpression and SFRP5 deficiency may jointly promote ES metastasis. [ABSTRACT FROM AUTHOR]

C–C chemokine receptor 7 (CCR7) and its ligands CCL19 contributes to the directional migration of certain cancer cell lines, but its role in the migration of BMSCs remains vague. The aim of this study was to determine the possible interaction between CCL19-induced conditions and matrix metalloproteinases-9 (MMP9) expression in BMSCs. Cell migration using Transwell assay indicated that activation of CCR7 by its specific ligand, exogenous chemokine ligand 19 (CCL19), was associated with a significant linear increase. Western blot and real-time PCR indicated that CCL19/CCR7 significantly upregulated expression of MMP9, which is related to metastasis-associated genes. The CCL19/CCR7 interaction significantly enhanced phosphorylation of Akt, as measured by Western blot. P-Akt and MMP9 protein expression exhibited a time-dependent pattern, and the peak was at 48 h. LY294002 significantly abolished the effects of exogenous CCL19. These results suggest that CCL19/CCR7 contributes to the migration of BMSCs by upregulating MMP9 potentially via the PI3K/Akt pathway. [ABSTRACT FROM AUTHOR]