Fig. 4

hNET-homing peptides do not display a direct cytotoxicity in neuroblastoma cells. a Cytotoxicity profiles of varying concentrations of peptides GASNGINAYL, GASNGINAYLC, SLWERLAYGI or SLWERLAYGIC for SH-SY5Y (upper panel) and UKF-NB-4 (lower panel) cells upon 24 h treatment. b Representative microarray (left panel) and expression heatmap (right panel) revealing expression of cancer-biomarker genes (one spot per one gene) in non-treated SH-SY5Y cells, and SH-SY5Y cells treated with GASNGINAYLC and SLWERLAYGIC peptides. c Venn diagram summarizing the number of up- (Ca) and down-regulated (Cb) genes by both or individual hNET-homing peptides. (Da) qPCR showing differences in relative expression of monoamine transporter genes SLC6A2 (encoding hNET), SLC6A3 (encoding hDAT) and SLC6A4 (encoding hSERT) in neuroblastoma cell lines (expression normalized to HPRT1) (Db) Electrophoretic analysis of qPCR amplicons. L—100 bp DNA molecular weight marker. CTR—qPCR amplicons from UKF-NB-4 cDNA. NTC non-template control