Some Chemical Carcinogens for Leukaemia Induction and Their Animal Models

Animal models have been providing invaluable contributions to the better understanding of mechanisms of cancer (including leukaemias) development and effectiveness of most of the treatments. Chemical carcinogens are generally used to study the biology of cancers including leukaemias in many animal models, including rats and mice. The studies in most cases are aimed at the development and evaluation of cancer treatments and preventions. Some of the most common chemical carcinogens used in animal models for leukaemias include N-ethyl-N-nitrosourea (ENU), N-methyl-N-nitrosourea (MNU), dimethyl benz(a)anthracene (DMBA) and benzo(a)pyrene (BaP). This review provides highlights on different animal models of leukaemia induced by the chemical carcinogens mentioned earlier, at the same time discussing the contributions of these models to the leukaemia diagnosis in laboratory animal models for subsequent development of treatment.

Nestin Expression in the Adult Mouse Retina with Pharmaceutically Induced Retinal Degeneration

The present study investigated the temporal pattern and cellular localization of nestin in the adult mouse retina with pharmaceutically induced retinal degeneration using N-methyl-N-nitrosourea (MNU). After a single intraperitoneal injection of MNU in 8-week-old C57BL/6 mice, the animals were sacrificed at 1, 3, 5, 7, and 21 days (n = 6, in each stage). The eyes were examined by means of immunohistochemical tests using nestin, ionized calcium-binding adaptor molecule (Iba-1), CD11b, F4/80, and glial fibrillary acidic protein (GFAP). Western blot analysis and manual cell counting were performed for quantification. Nestin expression was increased after MNU administration. Nestin+/Iba-1+ cells were migrated into outer nuclear layer (ONL) and peaked at day 3 post injection (PI). Nestin+/CD11b+ cells were also mainly identified in ONL at day 3 PI and peaked at day 5. Nestin+/F4/80+ cells were shown in the subretinal space and peaked at day 3 PI. Nestin+/GFAP+ cells were distinctly increased at day 1 PI and peaked at day 5 PI. The up-regulation of nestin expression after MNU administration in adult mouse retinal microglia, and monocyte/macrophage suggests that when retinal degeneration progresses, these cells may revert to a more developmentally immature state. Müller cells also showed reactive gliosis and differentiational changes.