AMD3100 reduces CXCR4-mediated survival and metastasis of osteosarcoma by inhibiting JNK and Akt, but not p38 or Erk1/2, pathways in in vitro and mouse experiments

Abstract

Osteosarcoma (OS) has an unfavorable prognosis and tends to metastasize to lung tissue. Although the CXCL12-CXCR4 axis appears to affect progression and metastasis in numerous tumors, its mechanism and downstream pathways in OS remain unclear. We used western blotting and flow cytometry to detect CXCR4 and CXCR7 expression in two OS cell lines (LM8 and Dunn). An MTT assay was used to evaluate the effects of CXCL12 and AMD3100, a specific CXCR4 antagonist, on cell viability. Flow cytometry was utilized to analyze changes in apoptosis induced by serum deprivation following treatment with CXCL12 and AMD3100. A Transwell assay was used to assess cell migration in response to CXCL12 and AMD3100. Western blotting was performed to identify the phosphorylation of signaling molecules (JNK, c-Jun, Akt, p38 and Erk1/2) and expression of caspase-3 and -8, and PARP. Mouse models were employed to evaluate AMD3100 inhibition of primary OS growth and lung metastasis in vivo. CXCR4 expression was detected in LM8 but not Dunn cells, and neither cell line expressed CXCR7. The addition of CXCL12 induced the survival and migration of serum-starved CXCR4+ LM8 cells activating JNK and Akt pathways, which were abrogated by adding AMD3100. However, similar results were not observed in CXCR4− Dunn cells. CXCL12 protected LM8, but not Dunn cells, from apoptosis induced by serum deprivation by suppressing PARP cleavage, which was partly reversed by AMD3100. In a mouse model, AMD3100 reduced primary tumor growth and lung metastasis compared with the controls. Thus, the CXCL12-CXCR4 axis regulated OS survival and metastasis through the JNK and Akt pathways, and blocking them with AMD3100 was found to be a potential OS treatment.

CoCl2, a mimic of hypoxia, enhances bone marrow mesenchymal stem cells migration and osteogenic differentiation via STAT3 signaling pathway

“…FAK localizes to sites of transmembrane integrin receptor clustering, and facilitates intracellular signaling events and cell migration (Sieg et al, ; Thakur et al, ). JNK and FAK also signal via CXCR4 and MMP family to facilitate intracellular signaling and cell migration (Liao et al, ; Mon et al, ). We found that hypoxia enhanced JNK and FAK phosphorylation, and STAT3 inhibition suppressed JNK and FAK phosphorylation.…”

CXCL12 expression promotes esophageal squamous cell carcinoma proliferation and worsens the prognosis

“…Zhou et al reported that CXCR4 mediates survival of glioma cells through Akt pathway [ 30 ]. Moreover, Liao et al reported that AMD3100 reduces CXCR4-mediated survival and metastasis of osteosarcoma by inhibiting JNK and Akt, but not p38 or Erk1/2, pathways [ 31 ]. To assess whether CXCL12/CXCR4 is involved in survival or apoptosis of ESCC, further studies are needed, including an examination of signal transduction following CXCL12-CXCR4 binding.…”

CXCR4 and CCR7: Two eligible targets in targeted cancer therapy

“…Phosphoinositide 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways are important downstream pathways of CXCR4 with implication on tumor cell survival and migration (Barbero et al, 2003). It was demonstrated that SDF-1 induces matrix metalloproteinases 9 (MMP-9) expression in prostate cancer cells by activating PI3K-Akt and MEK pathways (Chinni et al, 2006) and that binding of SDF-1 to CXCR4 induces cell invasiveness by triggering the extracellular signal regulated kinases 1/2 (ERK1/2) and PI3K (Leelawat et al, 2007;Liao et al, 2015). Many proteinases are capable of degradation of extracellular matrix (ECM).…”