c-Maf suppresses human T-cell leukemia virus type 1 Tax by competing for CREB-binding protein

IFN-α affects Th17/Treg cell balance through c-Maf and associated with the progression of EBV- SLE

OBJECTIVES

Systemic lupus erythematosus (SLE) is a multi-organ autoimmune disease, of which the pathogens is remains obscure. Viral infection, particularly Epstein Barr viru (EBV) infection, has been considered a common pathogenic factor. This study suggests that c-Maf may be an important target in T cell differentiation during SLE progression, providing a potentially new perspective on the role of viral infection in the pathogenesis of autoimmune diseases.

METHODS

Cytokines of EBV-infected SLE patients were measured by ELISA and assessed in conjunction with their clinical data. IFN-α, c-Maf, and the differentiation of Th17/Treg cells in SLE patients and MRL/LPR mice were analyzed using FCM, WB, RT-PCR, etc. Following the infection of cells and mice with EBV or viral mimic poly (dA:dT), the changes of the aforementioned indicators were investigated. The relationship among IFN-α, STAT3, c-Maf and Th17 cells was determined by si-RNA technique.

RESULTS

Many SLE patients are found to be complicated by viral infections; Further, studies have demonstrated that viral infection, especially EBV, is involved in SLE development. This study showed that viral infections might promote IFN-α secretion, inhibit c-Maf expression by activating STAT3, increase Th17 cell differentiation, and lead to the immune imbalance of Th17/Treg cells, thus playing a role in the onset and progression of SLE.

CONCLUSION

This study demonstrates that EBV infections may contribute to SLE development by activating STAT3 through IFN-α, inhibiting c-Maf, and causing Th17/Treg immune imbalance. Our work provided a new insight into the pathogenesis and treatment of SLE.

SOX4 is a direct target gene of FRA-2 and induces expression of HDAC8 in adult T-cell leukemia/lymphoma

SOX4 is consistently expressed in ATL, is involved in ATL cell growth, and induces genes such as GCRK, NAP1, and HDAC8 in ATL. FRA-2/JUND and SOX4 form an important oncogenic cascade in ATL, leading to upregulation of genes such as HDAC8.

HTLV tax: a fascinating multifunctional co-regulator of viral and cellular pathways

Human T-cell lymphotropic virus type 1 (HTLV-1) has been identified as the causative agent of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The virus infects between 15 and 20 million people worldwide of which approximately 2-5% develop ATL. The past 35 years of research have yielded significant insight into the pathogenesis of HTLV-1, including the molecular characterization of Tax, the viral transactivator, and oncoprotein. In spite of these efforts, the mechanisms of oncogenesis of this pleiotropic protein remain to be fully elucidated. In this review, we illustrate the multiple oncogenic roles of Tax by summarizing a recent body of literature that refines our understanding of cellular transformation. A focused range of topics are discussed in this review including Tax-mediated regulation of the viral promoter and other cellular pathways, particularly the connection of the NF-κB pathway to both post-translational modifications (PTMs) of Tax and subcellular localization. Specifically, recent research on polyubiquitination of Tax as it relates to the activation of the IkappaB kinase (IKK) complex is highlighted. Regulation of the cell cycle and DNA damage responses due to Tax are also discussed, including Tax interaction with minichromosome maintenance proteins and the role of Tax in chromatin remodeling. The recent identification of HTLV-3 has amplified the importance of the characterization of emerging viral pathogens. The challenge of the molecular determination of pathogenicity and malignant disease of this virus lies in the comparison of the viral transactivators of HTLV-1, -2, and -3 in terms of transformation and immortalization. Consequently, differences between the three proteins are currently being studied to determine what factors are required for the differences in tumorogenesis.