In the present study, mesothelin expression was evaluated using five different mouse monoclonal antibodies against mesothelin (clone 5B2 and MN-1) and MPF (megakaryocyte potentiating factor)/precursor mesothelin (MPF25, MPF44 and MPF49), in order to determine the optimal antibodies for mesothelin detection in common carcinomas. The gene discussed is MSLN; the disease is carcinoma.