Invasion of canine mammary cancer cell lines and growth characteristics in Matrigel matrix. (A) The graph of fluorescence intensity related to invasion of canine mammary cancer cell lines (CMT-U27, CMT-U309, P114, CMT-W1 and CMT-W2) grown as a mono-culture (ctrl) and as a co-culture with macrophages (+MQ). The statistical analysis was performed using Prism version 5.00 software (GraphPad Software, USA). The unpaired t-test was applied to analyze the results. p < 0.05 was regarded as significant and marked as * whereas p < 0.001 was regarded as highly significant and marked as ***. (B) Pictures of highly invaded CMT-W1 and CMT-W2 cells (green fluorescence) obtained using Olympus BX60 microscope examined in control conditions and after co-culturing with macrophages. (C) Growth characteristics of CMT-U27, CMT-U309, P114, CMT-W1 and CMT-W2 cell lines (phase contrast micrographs) grown on Matrigel matrix for 24 hrs.