Furthermore, MN1 overexpression also increases the penetrance of T-cell lymphoblastic leukemia and lymphoma (T-ALL/T-LBL) in combination with T-cell specific deletion of the tumour suppressor Pten. Finally, we confirm that luciferase-positive primary murine AML and T-ALL/T-LBL cells are transplantable in secondary recipients and can be readily used for preclinical drug testing purposes. The gene discussed is MN1; the disease is lymphoma.