Mouse models are irreplaceable tools for the study of carcinogenesis and the availability of rodent models have enabled rational screening of drugs. Hematological malignancies have been extensively studied in mouse models and broad range of lymphoid neoplasms has been reported in laboratory mice, occurring either spontaneously or after induction with radiation, chemicals or infection of newborn mice with leukemogenic viruses. Lymphomas are tumors that generally respond well to traditional therapies such as chemotherapy and radiotherapy. Dalton’s lymphoma is a transplantable T-cell lymphoma of spontaneous origin in thymus of murine host and has emerged as an interesting model for cancer research, because of its usefulness in pre-clinical system for evaluating new or known drugs in the treatment of various cancers and in drug discovery development process.

Introduction: Attention related to scientifi c and research interest towards naturally derived compounds from medicinal plant products as they are considered to have less toxic side effects as compared to current treatments such as chemotherapy. Medicinal plant produces naturally occurring secondary metabolites especially fl avonoids which are being investigated for their anticancer activities leading to the development of new clinical drugs.

We find more and more often patients with two or more synchronous or metachronous cancers, who raise various issues on the risk factors and pathways. A polycythemia vera male patient, diagnosed at 44 years, evolved towards secondary myeloid metaplasia which was then transformed into secondary acute myeloid leukemia. He also presented breast adenocarcinoma and a basal cell carcinoma of the nasal pyramid and of the internal angle of the left orbital region during those 13 years of evolution. Pathogenetic mechanisms are discussed, as well as the followed treatments and their effectiveness. The appearance of the four new malignancies infl uenced his quality of life and have reduced his survival.

Glucosylceramide synthase is the rate limiting enzyme in ceramide glycosylation and shifts the balance between ceramide and glycosphingolipids towards proliferation and survival of cancer cells. Increased glucose availability and glycolytic metabolism is preferentially used by cancer cells and has been linked to glycosphingolipid formation. We measured gene expression levels of glucosylceramide synthase and of glycolytic pathway enzymes, glucose transporter 1 and hexokinase II, as well as protein expression of glucosylceramide synthase, on trephine biopsy samples from 13 patients with hypereosinophilia, We found no signifi cant differences in expression levels of any of the enzymes in patients with secondary causes of hypereosinophilia compared to those with either suspected or proven clonal hypereosinophilia.