Table 1.

Expression of chemokine receptors at the surface of melanoma cells involved in tumor progression.

Chemokine Receptor	Roles in tumor development/progression	Clinical association	Cohort details	Statistical analyses	References
CCR4	Favor tumor cell viability, migration, primary tumor growth, and brain metastases formation	Not known	In vitro and preclinical models		(37)
CCR6	Enhanced tumor cell migration, proliferation, tumor growth, and lung metastasis formation	Not associated with patient outcome*	40 primary melanomas	Log-rank and Cox regression	(38)
CCR7	Associated with regional lymph node metastases	Poor prognosis	Preclinical model and 38 primary human samples	Log rank test—P = 0.009	(39, 40)
CCR9	Expressed on tumor cells localized in the small intestine–Sensitive to CCL25 stimulation	Not associated with patient outcome* or not assessed	38 primary samples	Log rank test	(40–42)
CCR10	Associated with an increase of regional lymph node metastases, metastatic sentinel lymph node, thickening of primary lesions and poor T cell density	Shorter progression free survival	40 primary lesions and 38 primary melanoma samples	Spearman correlation and Log rank test–P = 0.002	(40, 43, 44)
CXCR3	Associated with thick primary lesions, the absence of lymphocytic infiltration and the presence of distant metastases—Increase in cell adhesion, migration, and invasion of CXCR3 expressing melanoma cells lines upon stimulation.	Not associated with patient outcome*	Primary melanomas and 9 Lymph node metastases	χ2, Mann-Whitney U and Kruskal Wallis tests—Log-rank test and Cox regression	(45–48)
CXCR4	Associated with the presence of ulceration, thicker lesions—Induce tumor cell proliferation, migration, and invasion—Associated with liver and lung metastases	Reduced disease-free and overall survival	Primary melanomas and metastatic samples	χ2 2-sided test—Log-rank test and Cox regression	(47, 49–52)

^*Complementary analyses on larger cohorts are warranted.