It is therefore also noteworthy that the selective tumor p27Kip1 induction and tumor growth inhibition associated with Dex treatment of mice bearing the isogenic GR-high tumor xenografts vs. GR-low tumors, demonstrates that systemic factors do not play a significant role in the antitumor effects of Dex and that tumor GR status is the principal determinant of tumor sensitivity to Dex. The gene discussed is CDKN1B; the disease is neoplasm.