RESUMEN
Increasing evidence supports the involvement of acetylcholinesterase and butyrylcholinesterase in cell proliferation control and differentiation, reinforcing the hypothesis that these enzymes might have an influence in tumorigenesis. It has already been shown that the cholinesterase genes are structurally altered or aberrantly expressed in a variety of tumor types. In this study, amplifications and deletions in the ACHE and BCHE genes were investigated in sporadic breast tumors using real-time polymerase chain reaction and the relative quantification method. The majority of the tumor tissues showed a notable number of both deletions and amplifications: 65.7% and 22.9%, respectively, in BCHE and 45.7% and 31.4%, respectively, in ACHE. Deletion of the ACHE gene was significantly correlated with amplification of the protooncogene ERBB2. Tumor size was significantly higher when the ACHE gene was amplified, and the total number of alterations (amplifications plus deletions) of the BCHE gene was positively correlated with tumor malignancy grade.