Retroviral integration at the Epi1 locus cooperates with Nf1 gene loss in the progression to acute myeloid leukemia

Juvenile myelomonocytic leukemia (JMML) is a disease that occurs in young children and is associated with a high mortality rate. In most patients, JMML has a progressive course leading to death by virtue of infection, bleeding, or progression to acute myeloid leukemia (AML). As it is known that children with neurofibromatosis type 1 syndrome have a markedly increased risk of developing JMML, we have previously developed a mouse model of JMML through reconstitution of lethally irradiated mice with hematopoietic stem cells homozygous for a loss-of-function mutation in the Nf1 gene (D. L. Largaespada, C. I. Brannan, N. A. Jenkins, and N. G. Copeland, Nat. Genet. 12:137-143, 1996). In the course of these experiments, we found that all these genetically identical reconstituted mice developed a JMML-like disorder, but only a subset went on to develop more acute disease. This result strongly suggests that additional genetic lesions are responsible for disease progression to AML. Here, we describe the production of a unique tumor panel, created using the BXH-2 genetic background, for identification of these additional genetic lesions. Using this tumor panel, we have identified a locus, Epi1, which maps 30 to 40 kb downstream of the Myb gene and appears to be the most common site of somatic viral integration in BXH-2 mice. Our findings suggest that proviral integrations at Epi1 cooperate with loss of Nf1 to cause AML.     

Structure-based design of eugenol analogs as potential estrogen receptor antagonists

Eugenol is an essential oil mainly found in the buds and leaves of clove (Syzygium aromaticum (L.) Merrill and Perry), which has been reported to have activity on inhibition of cell proliferation and apoptosis induction in human MCF-7 breast cancer cells. This biological activity is correlated to its activity as an estrogen receptor antagonist. In this article, we present the construction and validation of structure-based virtual screening (SBVS) protocols to identify the potent estrogen receptor α (ER) antagonists. The selected protocol, which gave acceptable enrichment factors as a virtual screening protocol, subsequently used to virtually screen eugenol, its analogs and their dimers. Based on the virtual screening results, dimer eugenol of 4-[4-hydroxy-3-(prop-2-en-1- yl)phenyl]-2-(prop-2-en-1-yl)phenol is recommended to be developed further in order to discover novel and potent ER antagonists.     

Substitution of Cytokinins and Chlorophyll Breakdown in Detached Wheat Leaves

Four derivatives of benzyladenine with alkyl-substitution atthe 9 position, (9-methyl, 9-methoxymethyl, 9-tetrahydro-2-pyranyland 9-cyclopentyl-N⁶ benzyladenine), can slow, depending uponthe substituent and concentration, the breakdown of chlorophyllin detached wheat leaves. (Received June 9, 1984; Accepted September 25, 1984)