The non-tumorigenic melan-a melanocyte lineage[19] was cultured at 37°C in humidified 95% air-5% CO2 in RPMI pH 6.9 supplemented with 5% fetal bovine serum
(Invitrogen,Scotland,UK),200 nM 12-phorbol-13-myristate acetate(PMA;Calbiochem,Darmstadt,Germany),100 U/ml penicillin, and 100 U/ml streptomycin
(Invitrogen,GrandIsland,NY).PMA activates protein kinase C,and is required for melanocytes to survival and proliferate in culture [19].Pre-malignant 4C melanocyte
lineage, non-metastatic 4C11- and metastatic 4C11+ melanoma cell lines were cultured as melan-a cells,but in the absence of PMA,since they lost the requirement
of this factor to grow.Stably Timp1-overexpressing melan-a(MaT1S) and the control MaGFP were cultured in the same conditions described above in the presence
of PMA.The plasmid construction and transfection was previously described[17].Primary human melanocytes MP#2,kindly provided by Dr.Silvya Stuchi Maria-Engler (Faculdade de Ciências Farmacêuticas,Universidade de São Paulo),was cultured at 37°C in humidified 95% air-5 %CO2 in Cascade growth medium 254(Gibco,GrandIsland,NY) supplemented with 200 μM CaCl2 and 1% HGMS (human growth melanocyte supplement).The patient-derived metastatic melanoma cells Mel2,Mel3,
Mel4,Mel11,Mel14,Mel21,Mel25,Mel28 and Mel33 kindly provided by Dr.Débora C.P. Silva (Ludwig Institute for Cancer Research,São Paulo),were cultured at
37°C in humidified 95% air-5% CO2 in RPMI pH 7.2 supplemented with 15% fetal bovine serum (Invitrogen, Scotland,UK),1 mM sodium piruvate, 2 mM Lglutamine and antibiotics (Gibco,Grand Island,NY).