In addition to these cancer related functions, observations such as occurrence of frequent structural and numerical aberrations in the chromosomal region 1q21 [42, 43] (where most of the S100 gene members are located [2]) in human cancers; and altered mRNA and protein expression levels of several of the S100 members in different human malignancies [44–51] suggest that these proteins are closely related to human malignancies. This evidence concerns the gene S100A1 and cancer.