Expression of CC chemokine ligand 18 in cutaneous malignant melanoma tissues and its relationship with vascular endothelial growth factor and Ki67 antigen expressions

Abstract

Objective To measure the expression of CC chemokine ligand 18 (CCL18) in cutaneous malignant melanoma (CMM) tissues, and to explore its clinical significance, as well as relationship with vascular endothelial growth factor (VEGF) and Ki67 antigen expressions. Methods Immunohistochemistry was performed to measure CCL18, VEGF and Ki67 expressions in 58 paraffin-embedded CMM tissue specimens, as well as CCL18 expression in 20 paraffin-embedded pigmented nevus specimens, and immunofluorescence assay to confirm the expression of CCL18 in fresh CMM tissue specimens. Correlations of CCL18 expression with CMM clinicopathologic features, VEGF and Ki67 expressions were analyzed. Results CCL18 was detected in 49 (84.48%) of 58 paraffin-embedded CMM specimens, but in none of the 20 paraffin-embedded pigmented nevus specimens, with a significant difference in the positive rate of CCL18 between the CMM group and pigmented nevus group (χ2 = 45.46, P 0.05). In addition, the expression of CCL18 in CMM tissues was positively correlated with that of VEGF (rs = 0.727, P 0.05). Immunofluorescence assay showed CCL18 expression in the cytoplasm of tumor cells in CMM tissues. Conclusion CCL18 is highly expressed in CMM tissues, and may be involved in tumor invasion and metastasis. Key words: Nevi and melanomas; Chemokine CCL18; Pathologic processes; Vascular endothelial growth factors; Ki-67 antigen