Abstract: Described are methods for reducing the proliferation cancer cells by modulating the expression or activity of TOX such as by use of a TOX inhibitor. Inhibiting TOX expression with antisense nucleic acids is shown to reduce the proliferation of malignant T cells. Also described are methods for the treatment of cancer in a subject in need thereof comprising administering to the subject a TOX inhibitor. Optionally, the cancer is a T cell malignancy such as Cutaneous T cell Lymphoma (CTCL).

Abstract: Described are biomarkers including TOX useful for the diagnosis or prognosis of T cell malignancy. A level of a biomarker is determined in a sample from a subject and compared to a control level, wherein an increased level of the biomarker in the sample relative to the control level indicates that the subject has T cell malignancy. The T cell malignancy may be a cutaneous T cell lymphoma (CTCL) such as mycosis fungoides or Sezary syndrome.