We postulate that E- and N-cadherin modulation by SFN depends on the initial protein composition of the tumor cells, whereby well-differentiated RT4 cells (strongly E-cadherin positive, N-cadherin negative) stand in opposition to poorly differentiated tumor cells, particularly TCCSUP and T24 (E-cadherin negative, N-cadherin positive). The gene discussed is CDH1; the disease is neoplasm.