Our results suggest that Pit-1-CXCL12-CXCR4 axis could be involved in chemotaxis guidance during the metastatic process, and may represent prognostic and/or therapeutic targets in breast tumors.
In particular, <i>Cxcl12</i> expression was strongly enhanced in interleukin 7-producing fibroblasts and cell type-specific genetic ablation and systemic pharmacological inhibition revealed that the CXCL12/CXCR4 axis impacts breast tumor cell stemness.
Analysis of the gene expression profiles of breast tumours revealed that the highest expression levels of CXCR4 and CXCR7 were in the Claudin-Low molecular subtype, which is markedly associated with EMT features.
Clinical analysis of data herein demonstrated for the first time that overexpression of LL-37 and CXCR4 co-existed in human primary breast tumors with lymph node metastases.
<i>in-silico</i> analysis finds that CXCL12-CXCR4 is associated with an increased expression of PDZK1, PI3k and Akt which lead the breast tumor towards metastasis.
We conclude that tumor cell-derived ANGPTL2 may increase bone metastasis by enhancing breast tumor cell responsiveness to CXCL12 signaling through up-regulation of tumor cell CXCR4 expression.
Inhibition of CXCR4 expression by TPD7 further correlated with the suppression of SDF-1α-induced migration and invasion in breast tumour cells, knockdown of CXCR4 attenuated TPD7-inhibitory effects.
We used dual luciferase imaging to investigate CXCR7-dependent scavenging of CXCL12 in breast tumors in vivo and quantify effects of CXCR7 on tumor growth and metastasis of a separate population of CXCR4+ breast cancer cells.
Finally, anti-metastatic activity of BD in vivo was further confirmed by the downregulation of expression of PLAU (urokinase plasminogen activator, uPA) and CXCR4 (C-X-C chemokine receptor-4) genes in breast tumors.
These data also provide support for distinct biological functions of CXCR4 and CXCR7 and suggest that targeting CXCR4 and/or CXCR7 would have distinct molecular effects on ER-positive breast tumors.
Human immunodeficiency virus-induced apoptosis of human breast cancer cells via CXCR4 is mediated by the viral envelope protein but does not require CD4.
Carboxyl-terminal Src kinase homologous kinase negatively regulates the chemokine receptor CXCR4 through YY1 and impairs CXCR4/CXCL12 (SDF-1alpha)-mediated breast cancer cell migration.