0000000000353847
AUTHOR
Christoph Plass
Differential expression of the tumor suppressor A-kinase anchor protein 12 in human diffuse and pilocytic astrocytomas is regulated by promoter methylation
The scaffold protein A-kinase anchor protein 12 (AKAP12) exerts tumor suppressor activity and is downregulated in several tumor entities. We characterized AKAP12 expression and regulation in astrocytomas, including pilocytic and diffusely infiltrating astrocytomas. We examined 194 human gliomas and 23 normal brain white matter samples by immunohistochemistry or immunoblotting for AKAP12 expression. We further performed quantitative methylation analysis of the AKAP12 promoter by MassARRAY® of normal brain, World Health Organization (WHO) grade I to IV astrocytomas, and glioma cell lines. Our results show that AKAP12 is expressed in a perivascular distribution in normal CNS, strongly upregula…
Epigenetic differences arise during the lifetime of monozygotic twins.
Monozygous twins share a common genotype. However, most monozygotic twin pairs are not identical; several types of phenotypic discordance may be observed, such as differences in susceptibilities to disease and a wide range of anthropomorphic features. There are several possible explanations for these observations, but one is the existence of epigenetic differences. To address this issue, we examined the global and locus-specific differences in DNA methylation and histone acetylation of a large cohort of monozygotic twins. We found that, although twins are epigenetically indistinguishable during the early years of life, older monozygous twins exhibited remarkable differences in their overall…
NFATc1 Is Transcriptionally Activated in Chronic Lymphocytic Leukemia (CLL) By Promotor DNA-Hypomethylation Which Correlates with in-Vitro Vulnerability to Calcineurin Inhibitors
Abstract Chronic lymphocytic leukemia (CLL), the most frequent adult leukemia in Western countries, is characterized by progressive accumulation of mature, monoclonal B lymphocytes in blood, bone marrow, and lymphoid tissues. In the pathogenesis and treatment of CLL, B cell receptor (BCR) signaling plays a crucial role, and aberrations in downstream pathways that become activated in CLL need to be better defined. One downstream target of BCR signaling is NFATc1, a transcription factor with a high oncogenic and transforming potential. Employing a genome-wide comparative DNA methylation analysis the NFATc1 5’ region was identified to be DNA hypomethylated in CLL patient samples. The pilot ser…