Search results for "Hsp70"
showing 10 items of 206 documents
Inhibition of HSP70: a challenging anti-cancer strategy.
2012
HSP70 is a chaperone that accumulates in the cells after many different stresses promoting cell survival in response to the adverse conditions. In contrast to normal cells, most cancer cells abundantly express HSP70 at the basal level to resist to various insults at different stages of tumorigenesis and during anti-cancer treatment. This cancer cells addiction for HSP70 is the rational for its targeting in cancer therapy. Much effort has been dedicated in the last years for the active search of HSP70 inhibitors. Additionally, the recent clinical trials on highly promising inhibitors of another stress protein, HSP90, showed compensatory increase in HSP70 levels and raised the question of nec…
Dual regulation of SPI1/PU.1 transcription factor by heat shock factor 1 (HSF1) during macrophage differentiation of monocytes
2014
International audience; : In addition to their cytoprotective role in stressful conditions, heat shock proteins (HSPs) are involved in specific differentiation pathways, e.g. we have identified a role for HSP90 in macrophage differentiation of human peripheral blood monocytes exposed to Macrophage Colony-Stimulating Factor (M-CSF). Here, we show that deletion of the main transcription factor involved in heat shock gene regulation, heat shock factor 1 (HSF1), affects M-CSF-driven differentiation of mouse bone marrow cells. HSF1 transiently accumulates in the nucleus of human monocytes undergoing macrophage differentiation, including M-CSF-treated peripheral blood monocytes and phorbol ester-…
Oligodendroglioma cells shed microvesicles which contain TRAIL as well as molecular chaperones and induce cell death in astrocytes.
2011
Microvesicles (MVs) shed from G26/24 oligodendroglioma cells were previously reported to cause a reproducible, dose-dependent, inhibitory effect on neurite outgrowth, and eventually neuronal apoptosis, when added to primary cultures of rat cortical neurons. These effects were reduced but not abolished by functional monoclonal antibodies against Fas-L. In order to investigate whether MVs contain other factors able to induce cell death, we tested them for TRAIL and found clear evidence of its presence in the vesicles. This finding suggests the possibility that Fas-L and TRAIL cooperate in inducing brain cell death. Aimed at understanding the route through which the vesicles deliver their mess…
Oncolytic parvovirus H1 induces release of heat-shock protein HSP72 in susceptible human tumor cells but may not affect primary immune cells.
2003
Certain autonomous parvoviruses preferentially replicate in and kill in vitro-transformed cells and may reduce the incidence of spontaneous and implanted tumors in animals. Hence, these viruses and their derivatives are currently under evaluation as antitumor vectors. However, the mechanisms underlying their tumor-suppressing properties are not yet understood. We asked whether the lytic parvovirus H1 may enhance the immunogenicity of infected tumor cells. Out of human melanoma and gastrointestinal tumor cells, we selected the cell line SK29-Mel-1 being very susceptible to H1-induced apoptotic killing. Here, no upregulation of HLA class I and costimulatory molecules could be observed followi…
Analysis of differentially expressed proteins in oral squamous cell carcinoma by MALDI-TOF MS
2010
J Oral Pathol Med (2010) 40: 369–379 Purpose: To explore the presence of differentially expressed proteins in OSCC for discrimination of tumour and normal mucosa to establish potential biomarkers and therapeutic targets. Experimental Design: Paired protein samples of 12 individuals (tongue cancer and non-cancerous mucosa) were separated by two-dimensional polyacrylamid gel electrophoresis. The protein patterns were compared pairwise and protein spots were quantified. We identified about 70 regulated proteins which we subsequently identified by MALDI-TOF mass spectrometry. Results: Cancerous and non-cancerous tissues could be most precisely distinguished by a panel of proteins. They inclu…
Molecular Approaches to Target Heat Shock Proteins for Cancer Treatment
2015
HSP90 was the first molecular target to inhibit the interaction of this heat shock protein (HSP) with client proteins in cancer cells and tissues. The HSP90 inhibition was attempted to liberate from this chaperone the oncogenic fusion proteins, mutated and activated serine/threonine protein kinases, tyrosine kinases, as well as transcription factors with oncogenic activity, in this manner, the free proteins could be recognized by the proteasome system to be degraded. We should remember here that many HSP family members are overexpressed in different kinds of cancer tissues, these molecules act as chaperones of tumorigenesis. In cancer patients, the first generation of HSP90 inhibitors showe…
1267 HSP70-2 polymorphism as a risk factor for carotid plaque rupture and cerebral ischaemia in old type 2 diabetes-atherosclerotic patients.
2005
Patients with type 2 diabetes mellitus (NIDDM) are at risk for macrovascular disease complications, such as myocardial infarction (MI) or stroke from plaque rupture. Cytokines play a key role in plaque vulnerability. IFN-gamma inhibits collagen synthesis thereby affecting plaque stability. High IL-6, TNF-alpha, and dyslipidemia are risk factors for thrombosis. Abnormal increments of HSP70 in atherosclerotic plaques might lead to plaque instability and rupture caused by chronic inflammation, which up-regulates the expression of pro-inflammatory cytokines (IL-6 and TNF-alpha) in human monocytes. Studies of a polymorphic PstI site lying in the coding region at position 1267 of the HSP70-2 gene…
Impacts of UV-B radiation on short-term cultures of sea urchin coelomocytes
2006
Three specialized cell types constitute the heterogeneous population present in the coelomic cavity fluid of sea urchins. The list includes: phagocytes, which undergo a stress-induced petaloid-filopodial transition, white or red amoebocytes and vibratile cells. As a whole, they act as the immune defense system of the sea urchin and respond to environmental and experimental challenge triggering specific stress markers. Here we extended our studies on coelomocytes short-term cultures by describing the morphology and occurrence of each cell type and analyzing their response to UV-B radiation at the biochemical level and with respect to DNA damage. The effects of different doses, ranging from 5…
Double Face of eHsp70 in Front of Different Situations
2018
The Hsp70 family is one of the best conserved and abundant member of the heat shock proteins (HSP). This family includes several members and in particular one constitutively expressed member (Hsc70) and another one inducibly expressed under several stress conditions (Hsp70). To date, the intracellular functions of Hsp70 are well defined, and increasing evidences establish its roles in the extracellular environment, such as cytoprotection and immunomodulation. Increasing evidences suggest that several cell types are able to release Hsp70 in the extracellular environment, both under physiological and stress conditions. At the same time many release mechanisms have been identified. This chapte…
The effect of cadmium on brain cells in culture
2009
Cadmium is a long-living heavy metal, abundantly present in the environment, which accumulates in the body. In this study, we investigated the effects of cadmium on the expression of molecular chaperones, and of certain cell-specific proteins, in a variety of brain cell types in culture, namely primary cultures of rat cortical neurons and astrocytes, a brain capillary endothelial cell line (RB4E.B cells), and pheochromocytoma cells (PC12), induced or not to differentiate by NGF treatment. The metal induces a dose-dependent increase of Hsp70 in all cell types. Responses to the metal are cell-specific in the case of Hsc70 and Hsp90: i) in astrocytes, as well as in PC12 cells, cadmium has no s…