Quantitative analysis of S100 proteins, given as box-plot graphs, of matched breast cancer tissues (BCT) and non tumoral adjacent tissues (NAT). Quantification was deduced by the 2 D gels, analyzed by Image-Master software. In ordinate are the values of N%V. Statistical significance was analyzed by the Student's t-test: *p < 0.05 was considered significant; **p < 0.01 highly significant; ***p < 0.001 very highly significant. The data in the graphs are expressed as median ±SD.