ObjectiveTo examine the role of CCL14 in the neovascularization process and vulnerability progression within carotid plaques by investigating the mechanism of CCL14 regulation of VEGF-A. MethodsWe first performed histological analysis and immunohistochemical staining of human carotid plaque tissue to detect the expression of CCL14, JAK2, STAT3 and VEGF-A. We next examined the protein expression of CCL14, VEGF-A, JAK2, STAT3, and phosphorylation of JAK2 and STAT3 in human carotid atherosclerotic plaques by Western blotting. Finally, we performed in vitro culture of human umbilical vein endothelial cells (HUVEC). In the tube formation assay of HUVEC, we added CCL14 siRNA or VEGF-A siRNA to the culture medium using lentiviral transfection to knock down CCL14 or VEGF-A and grouped them for control assays, and detected the changes in the expression of the above proteins using Western blotting. ResultsHistological and Western blotting analysis of human carotid plaque samples showed that the expression of CCL14 and VEGF-A was higher in the vulnerable plaques than in stable plaques. In the in vitro cultures of HUVEC, CCL14 was found to increase the number and length of intercellularly generated tubular structures. CCL14 increases VEGF-A expression via activating JAK2/STAT3 signaling. ConclusionIn the human carotid plaques, CCL14 promotes angiogenesis by upregulation of VEGF-A via JAK2/STAT3 pathway and thus drives the progression of carotid plaques vulnerability.
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