DMF treatment inhibits CTCL cell and tumor growth in subcutaneous and orthotopic xenograft mouse models. NSG mice were xenografted with HH cells intradermally and treated once daily with either 30 mg/kg bodyweight of DMF or PBS by IP injection. (n = 37 each). In the subcutaneous model, the NSG mice were xenografted with HH cells subcutaneously and treated once daily with either 20 mg/kg bodyweight of DMF or PBS orally by gavage (n = 20 each). (A) Macroscopic pictures of a representative primary HH tumor of the respective mouse from either a PBS-treated (upper) or a DMF-treated (lower) animal in the intradermal model. (B) Survival curves of NSG mice. Decrease in survival is either caused by spontaneous death or by reaching critical tumor size of 1.5 cm at the largest diameter. (C) Percent survival rate of orthotopically xenografted mice treated with PBS or DMF at day 29, the end of the treatment phase. (D) Median time of tumor growth in PBS- and DMF-treated intradermal CTCL xenograft mice from first detection of a tumor to either death or the end of the experiment. (E) Median tumor volume of PBS- and DMF-treated intradermal CTCL xenograft mice over time. (F) Median tumor volume of subcutaneous HH xenografts of mice treated with either 20 mg/kg bodyweight DMF or PBS by oral gavage (n = 20, each) over time. (G) Median tumor volume in PBS- and DMF-treated subcutaneous CTCL xenografts at day 20. *P < .05.