The protozoan parasite Theileria annulata alters the differentiation state of the infected macrophage and suppresses musculoaponeurotic fibrosarcoma oncogene (MAF) transcription factors
INTERNATIONAL JOURNAL FOR PARASITOLOGY
Authors: Jensen, Kirsty; Makins, Giles D.; Kaliszewska, Anna; Hulme, Martin J.; Paxton, Edith; Glass, Elizabeth J.
Abstract
The tick-borne protozoan parasite Theileria annulata causes a debilitating disease of cattle called Tropical Theileriosis. The parasite predominantly invades bovine macrophages (m phi) and induces host cell transformation by a mechanism that has not been fully elucidated. Infection is associated with loss of characteristic m phi functions and phenotypic markers, indicative of host cell de-differentiation. We have investigated the effect of T annulata infection on the expression of the m phi differentiation marker c-maf. The up-regulation of c-maf mRNA levels observed during bovine monocyte differentiation to m phi was suppressed by T annulata infection. Furthermore, mRNA levels for c-maf and the closely related transcription factor mafB were significantly lower in established T. annulata-infected cell-lines than in bovine monocyte-derived m phi. Treatment of T. annulata-infected cells with the theileriacidal drug buparvaquone induced up-regulation of c-maf and malB, which correlated with altered expression of down-stream target genes, e.g. up-regulation of integrin B7 and clown-regulation of IL12A. Furthermore, T. annulata infection is associated with the Suppression of the transcription factors, Pu.1 and RUNX1, and colony stimulating factor 1 receptor (CSF1R) which are also involved in the regulation of monocyte/m phi differentiation. We believe these results provide the first direct evidence that T. annulata modulates the host m phi differentiation state, which may diminish the defence capabilities of the infected cell and/or promote cell proliferation. Musculoaponeurotic fibrosarcoma oncogene (MAF) transcription factors play an important role in cell proliferation, differentiation and survival; therefore regulation of these genes may be a major mechanism employed by T. annulata to Survive within the infected m phi. (C) 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.
Association of JAK-STAT pathway related genes with lymphoma risk: results of a European case-control study (EpiLymph)
BRITISH JOURNAL OF HAEMATOLOGY
Authors: Butterbach, Katja; Beckmann, Lars; de Sanjose, Silvia; Benavente, Yolanda; Becker, Nikolaus; Foretova, Lenka; Maynadie, Marc; Cocco, Pierluigi; Staines, Anthony; Boffetta, Paolo; Brennan, Paul; Nieters, Alexandra
Abstract
P>Previous studies have suggested an important role for the Janus kinase-signal transducer and activator of transcription (JAK-STAT) signalling pathway in tumour development. Therefore, we explored genetic variants in JAK-STAT pathway associated genes with lymphoma risk. In samples of the EpiLymph case-control study we genotyped 1536 single nucleotide polymorphisms (SNPs) using GoldenGate BeadArray (TM) Technology (Illumina, San Diego, CA, USA). Here, we report the associations between selected SNPs and haplotypes of the JAK-STAT pathway and risk of Hodgkin lymphoma (HL), B-cell non-Hodgkin lymphoma (B-NHL) and most frequent B-NHL subtypes. Among 210 relevant JAK-STAT pathway-related SNPs, polymorphisms in nine genes (BMF, IFNG, IL12A, SOCS1, STAT1, STAT3, STAT5A, STAT6, TP63) were significantly associated with lymphoma risk. At a study-wise significance level, we obtained a risk reduction of 28% among carriers of the heterozygous genotype of the STAT3 variant (rs1053023) for B-NHL. For six other variants within the STAT3 gene we observed an inverse association with different lymphoma subtypes. A reduced risk for HL was observed for the heterozygous genotype of the STAT6 SNP (rs324011). This is an explorative investigation to examine associations between JAK-STAT signalling related genes and lymphoma risk. The results implicate a relevant role of certain pathway-related genes in lymphomagenesis, but still need to be approved by independent studies.