CXCL12 expression in breast normal and tumour cell lines and expression after 5-aza-2'-deoxycytidine (5-aza-CdR) treatment. (A) The bands represent positive results for CXCL12 expression (383 bps) and GAPDH gene was used as housekeeping control (296 bps). (B) CXCL12 expression evaluation after 5-aza-CdR treatment in MDA-MB-435, MDA-MB-436 and MDA-MB-231 cell lines. The cell lines named Mock were not treated, and those named 5-aza-CdR were treated showing the re-expression of CXCL12 on these cell lines. H2O was used as negative control and MM 100 bp was used as a molecular weight marker.