Search results for "P[6]"

Post-translational modifications of hsp60 and its extracellular release via exosomes are induced by the histone deacetylase inhibitor (HDACi) SAHA in…

2015

The chaperonin Hsp60 has multiple functions, among which that of supporting the growth of some type of tumours (1). HDACi (histone-deacetylase inhibitors) are drugs that regulate gene expression via modulation of epigenetic mechanisms, and induce tumor-cell death (2). Here, we show that in the tumor cells H292 the HDACi SAHA decreases the intracellular level of Hps60 and promotes its extracellular trafficking by exosomal vesicles. SAHA caused a time- and dose-dependent decrease in cell viability with a G/2M cell-cycle arrest at 24 h and cell death at 48 h. These effects were accompanied by production of reactive oxygen species and mitochondrial membrane-potential dissipation. The marked dec…

Changes in immunohistochemical levels and subcellular localization after therapy and correlation and colocalization with CD68 suggest a pathogenetic …

2011

In an earlier work, the role of heat shock protein (Hsp60) in the pathogenesis of ulcerative colitis (UC) was suggested by its significant increase in the pathological mucosa parallel with an increase in inflammatory cells. More data in this direction are reported in this work. We analyzed by immunohistochemistry biopsies of colon tissue from 2 groups of patients with UC and treated with either 5-aminosalicylic acid (5-ASA) alone or in combination with a probiotic. We looked for inflammatory markers and Hsp60. Both the treatments were effective in reducing symptoms but the group treated with both 5-ASA and probiotics showed better clinical results. Amelioration of symptoms was associated wi…

Hsp60 levels in the skeletal muscle are fibre-type specific and increase after endurance training

2014

Naïve Hsp60, similarly to GroEL, oligomerizes to build heptameric and tetradecameric structures.

2013

Heat shock protein 60 (Hsp60) modulation by the Histon Deacetylase Inhibitor (HDAC-i) SAHA in mucoepidermoid tumor H292 cells

2014

Immune evasion proteins gpUS2 and gpUS11 of human cytomegalovirus incompletely protect infected cells from CD8 T cell recognition

2009

AbstractHuman cytomegalovirus (HCMV) encodes four glycoproteins, termed gpUS2, gpUS3, gpUS6 and gpUS11 that interfere with MHC class I biosynthesis and antigen presentation. Despite gpUS2–11 expression, however, HCMV infection is efficiently controlled by cytolytic CD8 T lymphocytes (CTL). To address the role of gpUS2 and gpUS11 in antigen presentation during viral infection, HCMV mutants were generated that expressed either gpUS2 or gpUS11 alone without coexpression of the three other proteins. Fibroblasts infected with these viruses showed reduced HLA-A2 and HLA-B7 surface expression. Surprisingly, however, CTL directed against the tegument protein pp65 and the regulatory IE1 protein stil…

Serological, immunomorphological and bioinformatics analyses suggest Hsp60 is involved in Hashimoto’s thyroiditis pathogenesis.

2013

Hsp60 chaperonopathies and chaperonotherapy: targets and agents

2014

Hsp60 (Cpn60) assembles into a tetradecamer that interacts with the co-chaperonin Hsp10 (Cpn10) to assist client polypeptides to fold, but it also has other roles, including participation in pathogenic mechanisms.Hsp60 chaperonopathies are pathological conditions, inherited or acquired, in which the chaperone plays a determinant etiologic-pathogenic role. These diseases justify selection of Hsp60 as a target for developing agents that interfere with its pathogenic effects. We provide information on how to proceed.The information available encourages the development of ways to improve Hsp60 activity (positive chaperonotherapy) when deficient or to block it (negative chaperonotherapy) when pa…

Data mining-based statistical analysis of biological data uncovers hidden significance: clustering Hashimoto’s thyroiditis patients based on the resp…

2014

The pathogenesis of Hashimoto's thyroiditis includes autoimmunity involving thyroid antigens, autoantibodies, and possibly cytokines. It is unclear what role plays Hsp60, but our recent data indicate that it may contribute to pathogenesis as an autoantigen. Its role in the induction of cytokine production, pro- or anti-inflammatory, was not elucidated, except that we found that peripheral blood mononucleated cells (PBMC) from patients or from healthy controls did not respond with cytokine production upon stimulation by Hsp60 in vitro with patterns that would differentiate patients from controls with statistical significance. This "negative” outcome appeared when the data were pooled and ana…

Study of the cytolethal distending toxin (CDT)-activated cell cycle checkpoint. Involvement of the CHK2 kinase.

2001

AbstractThe bacterial cytolethal distending toxin (CDT) triggers a G2/M cell cycle arrest in eukaryotic cells by inhibiting the CDC25C phosphatase-dependent CDK1 dephosphorylation and activation. We report that upon CDT treatment CDC25C is fully sequestered in the cytoplasmic compartment, an effect that is reminiscent of DNA damage-dependent checkpoint activation. We show that the checkpoint kinase CHK2, an upstream regulator of CDC25C, is phosphorylated and activated after CDT treatment. In contrast to what is observed with other DNA damaging agents, we demonstrate that the activation of CHK2 can only take place during S-phase. Use of wortmannin and caffeine suggests that this effect is no…