CD44 and melanoma: Since high aldehyde dehydrogenase (ALDH) activity and increased expression of stem cell biomarkers, CD271, CD44 and CD34, were shown to be associated with the phenotypic plasticity of melanoma cells (Held et al., 2010; Luo et al., 2012; Paulis et al., 2015; Restivo et al., 2017), we performed the ALDEFLUOR assay and flow cytometry analysis to measure these biomarkers in GEM treated cells.