Wnt5a promotes ewing sarcoma cell migration through upregulating CXCR4 expression

Abstract

BackgroundAs 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.MethodsExpression 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.ResultsWnt5a 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.ConclusionsWnt5a 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.

Non-canonical WNT5A is a potential regulator of granulosa cell function in cattle

“…The increase in JUN mRNA levels was reflected by an increase in JUN protein levels. These data are consistent with studies showing that knock-down of WNT5A decreased phospho-JUN levels in a sarcoma cell line (Jin et al, 2012) and that WNT5A upregulated phospho-JUN levels in NIH3T3 fibroblasts (Nomachi et al, 2008). Pharmacological inhibition of MAPK8 or Rac1 blocked the ability of WNT5A to stimulate phosphorylation of JUN and expression of JUN and FOS (present study).…”

Stress-Induced CXCR4 Promotes Migration and Invasion of Ewing Sarcoma

“…Studies of Ewing sarcoma tumors and cell lines have previously identified a potential role for the CXCR4/SDF-1α axis in Ewing sarcoma pathogenesis [4, 16, 28, 29]. In particular, interrogation of gene expression databases identified an association between high levels of the CXCR4 transcript and metastatic disease [4].…”

LDOC1 regulates Wnt5a expression and osteosarcoma cell metastasis and is correlated with the survival of osteosarcoma patients

“…35 Many studies have reported that Wnt5a can increase the metastasis of osteosarcoma. [5][6][7][8][9][10] One study showed that Wnt5a can promote breast cancer cell migration via the Dvl2/Rab35/Rac1 signaling pathway. 36 In this study, we found that increased LDOC1 expression in osteosarcoma cells specifically decreases Wnt5a, but not Dvl2, levels.…”

“…2 The Wnt5a signaling pathway is involved in metastasis regulation in many tumor types, including osteosarcoma. [5][6][7][8][9][10] The LDOC1 (leucine zipper, down-regulated in cancer 1) protein has been shown to localize to the nucleus, and its expression is down-regulated in pancreatic and gastric cancer cells, compared to the corresponding normal human tissue. 11,12 These observations led to the hypothesis that LDOC1 functions as a tumor suppressor.…”