Lapatinib effects on Her2+ and Her2- canine mammary carcinoma cells cultured in vitro

Abstract

Breast neoplasms in female dogs, as well as in women, occur spontaneously and frequently. For this reason, the female dog is considered the main experimental model for this tumor in humans. Several drugs are used as adjuvant treatment for breast neoplasms, however some tumors do not respond adequately to established protocols. Lapatinib, a tyrosine kinase inhibitor, is a therapeutic alternative, especially against HER2+ neoplasms. HER2 is an upregulated proto-oncogene in 25 to 30% of breast neoplasms in women, and 21.8% in dogs. Thus, the study aims to evaluate the anti-tumor effect of lapatinib in canine mammary carcinoma HER2+ cells in vitro. The groups will be composed of HER2+ mammary carcinoma cells, HER2- mammary carcinoma cells and mammary cells without neoplastic alterations, treated or not with lapatinib. The samples will be obtained from a previously established canine mammary carcinoma cell bank. The concentration of lapatinib to inhibit 50% (IC 50) of cell growth will be determined. HER2 expression will be assessed by western blotting. Cell viability (tripan blue, MTT) and cell migration (wound healing) will be evaluated. Lapatinib is expected to inhibit HER2+ tumor growth as in humans, establishing its pathway in canine species. (AU)