Expression of chemokine CXCL12 and its receptor (CXCR4 and CXCR7) in different molecular subtypes of human breast carcinoma and the clinical significance

Abstract

To study the expressions and the clinical significance of chemokine CXCL12 and its receptor CXCR4, CXCR7 in the human breast carcinoma (BC) with different molecular subtypes. Methods: The mRNA expressions of CXCL12, CXCR4 and CXCR7 in tissues from 80 patients with different molecular subtype of BC were measured by qRT-PCR. The protein expressions of CXCL12, CXCR4 and CXCR7 in paraffin-embedded samples from 160 patients with different molecular subtypes were detected by immunohistochemical staining. Results: The mRNA expression levels of CXCL12, CXCR4 and CXCR7 in HER-2 positive BC and TNBC tissues were significantly higher than those in luminal A and luminal B subtype BC tissues (all P<0.05), but their expressions were not different between luminal A and luminal B subtype BC tissues or between HER-2 positive BC and TNBC tissues. The positive expression rates of CXCL12 protein in HER-2 positive BC and TNBC tissues were significantly higher than those in luminal A and luminal B subtype BC tissues (all P<0.05), while their expressions were not different between luminal A and luminal B subtype BC tissues or between HER-2 positive BC and TNBC tissues. High expressions of the gene CXCL12 and its receptor CXCR4 and CXCR7 in HER-2 positive BC and TNBC may be closely associated with their poor prognosis. Inhibition of their expressions in HER-2 positive BC and TNBC may provide a strategy for treating BC in clinic.