tetracycline and Precursor-Cell-Lymphoblastic-Leukemia-Lymphoma

The tetracycline regulatory system provides a tractable strategy to interrogate the role of oncogenes in the initiation and maintenance of tumorigenesis through both spatial and temporal control of expression. This approach has several potential advantages over conventional methods to generate genetically engineered mouse models. First, continuous constitutive overexpression of an oncogene can be lethal to the host impeding further study. Second, constitutive overexpression fails to model adult onset of disease. Third, constitutive deletion does not permit, whereas conditional overexpression of an oncogene enables the study of the consequences of restoring expression of an oncogene back to endogenous levels. Fourth, the conditional activation of oncogenes enables examination of specific and/or developmental state-specific consequences. Hence, by allowing precise control of when and where a gene is expressed, the tetracycline regulatory system provides an ideal approach for the study of putative oncogenes in both the initiation and maintenance of tumorigenesis. In this protocol, we describe the methods involved in the development of a conditional mouse model of MYC-induced T-cell acute lymphoblastic leukemia.

Topics: Animals; Cell Line; Disease Models, Animal; Female; Gene Expression; Gene Expression Regulation, Neoplastic; Gene Targeting; Genetic Vectors; Isografts; Male; Mice; Mice, Transgenic; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Proto-Oncogene Proteins c-myc; Tetracycline

Patients with ARF and haematological malignancy (excluding myeloma), presenting to a single unit over 10 years were analyzed to see if patients likely to benefit from intensive renal supportive therapy could be identified. 31 episodes of ARF were identified in 29 patients (mean age 51 +/- 2.9 yr): 19 were associated with acute leukaemia (13 AML, 6 ALL); 10 with lymphoma. Acute tubular necrosis (ATN) was identified as the cause of ARF in 26 cases, with sepsis (96%) and exposure to nephrotoxic drugs (88%), especially aminoglycosides, being the commonest precipitating factors. Toxic levels of the latter were commonly documented. Patient survival was 45%. Requirement for mechanical ventilation resulted in a universally fatal outcome; age greater than 55 yr and the presence of CNS symptoms or signs were also significantly associated with a poor outcome. Non-ATN causes (urate nephropathy or obstruction) carried a better prognosis. However, only 4 patients (14%) lived for more than 6 months following ARF. Thus, although a subgroup of patients more likely to benefit from treatment can be identified, the overall prognosis is poor and limited by that of the underlying disease. The potential benefit of avoiding nephrotoxic drugs, especially aminoglycosides, in these patients is highlighted by this study.

Topics: Acute Kidney Injury; Adolescent; Adult; Age Factors; Aged; Aminoglycosides; Cyclosporins; Female; Humans; Kidney Tubular Necrosis, Acute; Leukemia, Myeloid; Lymphoma; Male; Middle Aged; Neoplasms; Precursor Cell Lymphoblastic Leukemia-Lymphoma; Retrospective Studies; Risk Factors; Tetracycline