Expression levels of netrin-1 (NTN1), DCC, UNC5B and UNC5D were measured by quantitative RT-PCR. Breast cancer (HBL100), lung cancer (A549R, H322, H358), colon cancer (HCT116, HCT8), pancreatic cancer (MiaPacA-2, Panc-1), neuroblastoma (SH-Sy5y, IMR32), glioblastoma (SF767, U87MG) and ovarian cancer (PA-1, TOV-112D, NIH-OVCAR3) cell lines were treated with classical chemotherapeutic drugs (Doxorubicin, Cisplatin, 5-Fluorouracil and Taxol), at different drugs concentration dependent on IC50 values calculated for each cell line and drug treatment for 24 h. Netrin-1 and its receptors gene expression was compared to control, not-treated cells, values indicate fold over control changes. Standard deviation and statistical analysis are also indicated. –, no changes or downregulation; n.e., not expressed. Positive cell lines were determined for gene expression variations more than twofold over control. Grey boxes represent resistant (i.e. more than 50% cell survival after treatment with maximal drugs concentrations) cancer cell lines. p53 status is indicated for each cell line (WT, wild-type p53; MUT, mutated p53; NULL, deleted p53).