Human melanoma metastases express functional CXCR4.
OBJECTIVE
The chemokine receptor CXCR4 was identified as an independent predictor of poor prognosis in primary melanoma. The aim of the study was to investigate the role of CXCR4 in human melanoma metastases.


METHODS
CXCR4 expression was evaluated in melanoma metastases and in metastatic cell lines through immunohistochemistry, immunoblotting, immunofluorescence, and reverse transcription-PCR. The function of CXCR4 was tested in the presence of the ligand, CXCL12, through induction of extracellular signal-regulated kinase-1 and -2 (Erk-1 and -2) phosphorylation, proliferation, apoptosis, and migration capabilities.


RESULTS
CXCR4 expression was detected in 33 out of 63 (52.4%) metastases from cutaneous melanomas. Metastatic melanoma cell lines expressed cell surface CXCR4; PES 43, Alo 40, and COPA cell lines showed the highest levels of CXCR4 (>90% of positive cells); PES 41, Alo 39, PES 47, POAG, and CIMA cell lines showed low to moderate degrees of expression (5-65% of positive cells). Other chemokine receptors, CCR7 and CCR10, were detected on the melanoma cell lines; CXCL12 activated Erk-1 and Erk-2, the whose induction was specifically inhibited by AMD3100 treatment. CXCL12 increased the growth in PES 41, PES 43, and PES 47 cells under suboptimal (1% serum) and serum-free culture conditions; AMD3100 (1 mumol/L) inhibited the spontaneous and CXCL12-induced proliferation. No rescue from apoptosis was shown but PES 41, PES 43, and PES 47 cells migrate toward CXCL12.


CONCLUSIONS
These findings indicate that CXCR4 is expressed and active in human melanoma metastases, suggesting that active inhibitors such as AMD3100 may be experienced in human melanoma.
Scala
Stefania
S
Department of Clinical Immunology, National Cancer Institute, G. Pascale Foundation, Naples, Italy.
Giuliano
Paola
P
Ascierto
Paolo A
PA
Ieranò
Caterina
C
Franco
Renato
R
Napolitano
Maria
M
Ottaiano
Alessandro
A
Lombardi
Maria L
ML
Luongo
Monica
M
Simeone
Ester
E
Castiglia
Daniele
D
Mauro
Francesca
F
De Michele
Ileana
I
Calemma
Rosa
R
Botti
Gerardo
G
Caracò
Corrado
C
Nicoletti
Gianfranco
G
Satriano
Rocco A
RA
Castello
Giuseppe
G
D001596:Benzylamines; D015153:Blotting, Western; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D054377:Chemokine CXCL12; D019743:Chemokines, CXC / Q000494:pharmacology; D000080027:Cyclams; D004789:Enzyme Activation / Q000187:drug effects; D005455:Fluorescent Antibody Technique; D015972:Gene Expression Regulation, Neoplastic; D006571:Heterocyclic Compounds / Q000494:pharmacology; D006801:Humans; D007150:Immunohistochemistry; D008545:Melanoma / Q000235:genetics / Q000378:metabolism / Q000556:secondary*; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D019718:Receptors, CXCR4 / Q000096:biosynthesis* / Q000235:genetics; D019707:Receptors, Chemokine / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012867:Skin / Q000737:chemistry / Q000378:metabolism / Q000473:pathology; D013997:Time Factors
D001596:Benzylamines; C515255:CXCL12 protein, human; D054377:Chemokine CXCL12; D019743:Chemokines, CXC; D000080027:Cyclams; D006571:Heterocyclic Compounds; D019718:Receptors, CXCR4; D019707:Receptors, Chemokine; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; C088327:plerixafor