Efficient Heat Shock Response Affects Hyperthermia-Induced Radiosensitization in a Tumor Spheroid Control Probability Assay

Hyperthermia (HT) combined with irradiation is a well-known concept to improve the curative potential of radiotherapy. Technological progress has opened new avenues for thermoradiotherapy, even for recurrent head and neck squamous cell carcinomas (HNSCC). Preclinical evaluation of the curative radiosensitizing potential of various HT regimens remains ethically, economically, and technically challenging. One key objective of our study was to refine an advanced 3-D assay setup for HT + RT research and treatment testing. For the first time, HT-induced radiosensitization was systematically examined in two differently radioresponsive HNSCC spheroid models using the unique in vitro “curative” analytical endpoint of spheroid control probability. We further investigated the cellular stress response mechanisms underlying the HT-related radiosensitization process with the aim to unravel the impact of HT-induced proteotoxic stress on the overall radioresponse. HT disrupted the proteome’s thermal stability, causing severe proteotoxic stress. It strongly enhanced radiation efficacy and affected paramount survival and stress response signaling networks. Transcriptomics, q-PCR, and western blotting data revealed that HT + RT co-treatment critically triggers the heat shock response (HSR). Pre-treatment with chemical chaperones intensified the radiosensitizing effect, thereby suppressing HT-induced Hsp27 expression. Our data suggest that HT-induced radiosensitization is adversely affected by the proteotoxic stress response. Hence, we propose the inhibition of particular heat shock proteins as a targeting strategy to improve the outcome of combinatorial HT + RT.

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The Heat-Shock Response and Expression of Heat-Shock Proteins in Wheat Under Diurnal Heat Stress and Field Conditions

Functional Plant Biology ◽

10.1071/pp9940857 ◽

1994 ◽

Vol 21 (6) ◽

pp. 857 ◽

Cited By ~ 14

Author(s):

HT Nguyen ◽

CP Joshi ◽

N Klueva ◽

J Weng ◽

KL Hendershot ◽

...

Keyword(s):

Heat Stress ◽

Heat Shock ◽

Heat Shock Proteins ◽

Heat Tolerance ◽

Heat Shock Response ◽

Field Conditions ◽

Shock Response ◽

Heat Tolerant ◽

Shock Proteins

The occurrence of heat-shock proteins (HSPs) in response to high temperature stress is a universal phenomenon in higher plants and has been well documented. However, in agriculturally important species, less is known about the expression of HSPs under natural environments. A review of the heat-shock response in wheat (Triticum aestivum L.) is presented and recent results on the expression of wheat HSPs under diurnal stress and field conditions are reported. In the field experiment, flag leaf blade temperatures were obtained and leaf blades collected for northern blot analysis using HSP 16.9 cDNA as a probe. Temperatures of leaf blades ranged from 32 to 35�C under the tested field conditions at New Deal near Lubbock, Texas. Messenger RNAs encoding a major class of low molecular weight HSPs, HSP 16.9, were detected in all wheat genotypes examined. The results suggested that HSPs are synthesised in response to heat stress under agricultural production, and furthermore, that HSPs are produced in wheats differing in geographic background. In the controlled growth chamber experiment, HSP expression in two wheat cultivars, Mustang (heat tolerant) and Sturdy (heat susceptible) were analysed to determine if wheat genotypes differing in heat tolerance differ in in vitro HSP synthesis (translatable HSP mRNAs) under a chronic, diurnal heat-stress regime. Leaf tissues were collected from seedlings over a time-course and poly (A)+RNAs were isolated for in vitro translation and 2-D gel electrophoresis. The protein profiles shown in the 2-D gel analysis revealed that there were not only quantitative differences of individual HSPs between these two wheat lines, but also some unique HSPs which were only found in the heat tolerant line. This data provides evidence of a correlation between HSP synthesis and heat tolerance in wheat under a simulated field environment and suggests that further genetic analysis of HSPs in a segregating population is worthy of investigation. In conclusion, the results of this study provide an impetus for the investigation of the roles of HSP genes in heat tolerance in wheat.

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Systemic activation coordinates the heat shock response of the insulin/IGF-1 pathway in Caenorhabditis elegans

10.1101/131375 ◽

2017 ◽

Author(s):

Ronen B Kopito ◽

Kathie Watkins ◽

Erel Levine

Keyword(s):

Caenorhabditis Elegans ◽

Stress Response ◽

Heat Shock ◽

Heat Shock Response ◽

Cellular Response ◽

Precise Control ◽

Cellular Processes ◽

Shock Response ◽

Stressed Cells ◽

Shock Proteins

Exposure to high temperatures has an adverse effect on cellular processes and results in activation of the cellular heat shock response (HSR), a highly conserved program of inducible genes to maintain protein homeostasis1. The insulin/IGF-1 signaling (IIS) pathway, which has diverse roles from metabolism to stress response and longevity, is activated as part of the HSR2–4. Recent evidence suggest that the IIS pathway is able to affect proteostasis non-autonomously5,6, yet it is not known if it is activated autonomously in stressed cells or systemically as part of an organismic program. In Caenorhabditis elegans, the single forkhead box O (FOXO) homologue DAF-16 functions as the major target of the IIS pathway7 and, together with the heat-shock factor HSF-1, induce the expression of small heat shock proteins in response to heat shock8–10,3. Here we use a novel microfluidic device that allows precise control of the spatiotemporal temperature profile to show that cellular activation of DAF-16 integrates local temperature sensation with systemic signals. We demonstrate that DAF-16 activation in head sensory neurons is essential for DAF-16 activation in other tissues, but show that no known thermosensory neuron is individually required. Our findings demonstrate that systemic and cell-autonomous aspects of stress response act together to facilitate a coordinated cellular response at the organismic level.

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Urocortin 3 overexpression reduces ER stress and heat shock response in 3T3-L1 adipocytes

Scientific Reports ◽

10.1038/s41598-021-95175-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sina Kavalakatt ◽

Abdelkrim Khadir ◽

Dhanya Madhu ◽

Heikki A. Koistinen ◽

Fahd Al-Mulla ◽

...

Keyword(s):

Stress Response ◽

Heat Shock ◽

Er Stress ◽

Glucose Uptake ◽

Heat Shock Response ◽

Cellular Stress Response ◽

Mrna Levels ◽

Obesity And Diabetes ◽

Shock Response ◽

Urocortin 3

AbstractThe neuropeptide urocortin 3 (UCN3) has a beneficial effect on metabolic disorders, such as obesity, diabetes, and cardiovascular disease. It has been reported that UCN3 regulates insulin secretion and is dysregulated with increasing severity of obesity and diabetes. However, its function in the adipose tissue is unclear. We investigated the overexpression of UCN3 in 3T3-L1 preadipocytes and differentiated adipocytes and its effects on heat shock response, ER stress, inflammatory markers, and glucose uptake in the presence of stress-inducing concentrations of palmitic acid (PA). UCN3 overexpression significantly downregulated heat shock proteins (HSP60, HSP72 and HSP90) and ER stress response markers (GRP78, PERK, ATF6, and IRE1α) and attenuated inflammation (TNFα) and apoptosis (CHOP). Moreover, enhanced glucose uptake was observed in both preadipocytes and mature adipocytes, which is associated with upregulated phosphorylation of AKT and ERK but reduced p-JNK. Moderate effects of UCN3 overexpression were also observed in the presence of 400 μM of PA, and macrophage conditioned medium dramatically decreased the UCN3 mRNA levels in differentiated 3T3-L1 cells. In conclusion, the beneficial effects of UCN3 in adipocytes are reflected, at least partially, by the improvement in cellular stress response and glucose uptake and attenuation of inflammation and apoptosis.

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Quantitative proteomics identifies the universally conserved ATPase Ola1p as a positive regulator of heat shock response in Saccharomyces cerevisiae

10.1101/2021.05.12.443772 ◽

2021 ◽

Author(s):

Stefan Dannenmaier ◽

Christine Desroches Altamirano ◽

Lisa Schueler ◽

Ying Zhang ◽

Johannes Hummel ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Heat Stress ◽

Heat Shock ◽

Heat Shock Response ◽

De Novo ◽

Stress Granules ◽

Cellular Stress Response ◽

Protein Ubiquitination ◽

Shock Response

The universally conserved P-loop ATPase Ola1 is implicated in various cellular stress response pathways, as well as in cancer and tumor progression. However, Ola1p functions are divergent between species and the involved mechanisms are only poorly understood. Here, we studied the role of Ola1p in the heat shock response of the yeast Saccharomyces cerevisiae using a combination of quantitative and pulse labeling-based proteomics approaches, in vitro studies and cell-based assays. Our data show that when heat stress is applied to cells lacking Ola1p, the expression of stress-protective proteins is enhanced. During heat stress Ola1p associates with detergent-resistant protein aggregates and rapidly forms assemblies that localize to stress granules. The assembly of Ola1p was also observed in vitro using purified protein and conditions, which resembled those in living cells. We show that loss of Ola1p results in increased protein ubiquitination of detergent-insoluble aggregates recovered from heat-shocked cells. When subsequently cells lacking Ola1p were relieved from heat stress, reinitiation of translation was delayed, whereas, at the same time, de novo synthesis of central factors required for protein refolding and the clearance of aggregates was enhanced when compared to wildtype cells. The combined data suggest that upon acute heat stress, Ola1p is involved in the stabilization of misfolded proteins, which become sequestered in cytoplasmic stress granules. This function of Ola1p enables cells to resume translation in a timely manner as soon as heat stress is relieved.

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The amino acid substitution affects cellular response to mistranslation

10.1101/2021.05.12.443880 ◽

2021 ◽

Author(s):

Matthew D. Berg ◽

Yanrui Zhu ◽

Bianca Y. Ruiz ◽

Raphaël Loll-Krippleber ◽

Joshua Isaacson ◽

...

Keyword(s):

Amino Acid ◽

Heat Shock ◽

Amino Acid Substitution ◽

Heat Shock Response ◽

Cellular Response ◽

Genetic Interactions ◽

Similar Frequency ◽

Proteotoxic Stress ◽

Shock Response ◽

The Impact

Mistranslation, the mis-incorporation of an amino acid not specified by the standard genetic code, occurs in all organisms. tRNA variants that increase mistranslation arise spontaneously and engineered tRNAs can achieve mistranslation frequencies approaching 10% in yeast and bacteria. Interestingly, human genomes contain tRNA variants with the potential to mistranslate. Cells cope with increased mistranslation through multiple mechanisms, though high levels cause proteotoxic stress. The goal of this study was to compare the genetic interactions and the impact on transcriptome and cellular growth of two tRNA variants that mistranslate at a similar frequency but create different amino acid substitutions in Saccharomyces cerevisiae. One tRNA variant inserts alanine at proline codons whereas the other inserts serine for arginine. Both tRNAs decreased growth rate, with the effect being greater for arginine to serine than for proline to alanine. The tRNA that substituted serine for arginine resulted in a heat shock response. In contrast, heat shock response was minimal for proline to alanine substitution. Further demonstrating the significance of the amino acid substitution, transcriptome analysis identified unique up- and downregulated genes in response to each mistranslating tRNA. Number and extent of negative synthetic genetic interactions also differed depending upon type of mistranslation. Based on the unique responses observed for these mistranslating tRNAs, we predict that the potential of mistranslation to exacerbate diseases caused by proteotoxic stress depends on the tRNA variant. Furthermore, based on their unique transcriptomes and genetic interactions, different naturally occurring mistranslating tRNAs have the potential to negatively influence specific diseases.

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The amino acid substitution affects cellular response to mistranslation

G3 Genes|Genome|Genetics ◽

10.1093/g3journal/jkab218 ◽

2021 ◽

Author(s):

Matthew D Berg ◽

Yanrui Zhu ◽

Bianca Y Ruiz ◽

Raphaël Loll-Krippleber ◽

Joshua Isaacson ◽

...

Keyword(s):

Amino Acid ◽

Heat Shock ◽

Amino Acid Substitution ◽

Heat Shock Response ◽

Cellular Response ◽

Genetic Interactions ◽

Similar Frequency ◽

Proteotoxic Stress ◽

Shock Response ◽

The Impact

Abstract Mistranslation, the mis-incorporation of an amino acid not specified by the “standard” genetic code, occurs in all organisms. tRNA variants that increase mistranslation arise spontaneously and engineered tRNAs can achieve mistranslation frequencies approaching 10% in yeast and bacteria. Interestingly, human genomes contain tRNA variants with the potential to mistranslate. Cells cope with increased mistranslation through multiple mechanisms, though high levels cause proteotoxic stress. The goal of this study was to compare the genetic interactions and the impact on transcriptome and cellular growth of two tRNA variants that mistranslate at a similar frequency but create different amino acid substitutions in Saccharomyces cerevisiae. One tRNA variant inserts alanine at proline codons whereas the other inserts serine for arginine. Both tRNAs decreased growth rate, with the effect being greater for arginine to serine than for proline to alanine. The tRNA that substituted serine for arginine resulted in a heat shock response. In contrast, heat shock response was minimal for proline to alanine substitution. Further demonstrating the significance of the amino acid substitution, transcriptome analysis identified unique up- and downregulated genes in response to each mistranslating tRNA. Number and extent of negative synthetic genetic interactions also differed depending upon type of mistranslation. Based on the unique responses observed for these mistranslating tRNAs, we predict that the potential of mistranslation to exacerbate diseases caused by proteotoxic stress depends on the tRNA variant. Furthermore, based on their unique transcriptomes and genetic interactions, different naturally occurring mistranslating tRNAs have the potential to negatively influence specific diseases.

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Urea sensitizes mIMCD3 cells to heat shock-induced apoptosis: protection by NaCl

AJP Cell Physiology ◽

10.1152/ajpcell.2001.280.3.c614 ◽

2001 ◽

Vol 280 (3) ◽

pp. C614-C620 ◽

Cited By ~ 11

Author(s):

Chantal Colmont ◽

Stéphanie Michelet ◽

Dominique Guivarc'h ◽

Germain Rousselet

Keyword(s):

Heat Shock ◽

Heat Shock Response ◽

Heat Sensitivity ◽

Osmotic Gradient ◽

Water Reabsorption ◽

Apoptotic Pathway ◽

Shock Response ◽

Induced Apoptosis ◽

Shock Proteins ◽

Dose Dependent

Urea, with NaCl, constitutes the osmotic gradient that allows water reabsorption in mammalian kidneys. Because NaCl induces heat shock proteins, we tested the responses to heat shock of mIMCD3 cells adapted to permissive urea and/or NaCl concentrations. We found that heat-induced cell death was stronger after adaptation to 250 mM urea. This effect was reversible, dose dependent, and, interestingly, blunted by 125 mM NaCl. Moreover, we have shown that urea-adapted cells engaged in an apoptotic pathway upon heat shock, as shown by DNA laddering. This sensitization is not linked to a defect in the heat shock response, because the induction of HSP70 was similar in isotonic and urea-adapted cells. Moreover, it is not linked to the presence of urea inside cells, because washing urea away did not restore heat resistance and because applying urea and heat shock at the same time did not lead to heat sensitivity. Together, these results suggest that urea modifies the heat shock response, leading to facilitated apoptosis.

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Development of the embryonic heat shock response and the impact of repeated thermal stress in early stage lake whitefish ( Coregonus clupeaformis ) embryos

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2017.08.013 ◽

2017 ◽

Vol 69 ◽

pp. 294-301 ◽

Cited By ~ 7

Author(s):

Lindy M. Whitehouse ◽

Chance S. McDougall ◽

Daniel I. Stefanovic ◽

Douglas R. Boreham ◽

Christopher M. Somers ◽

...

Keyword(s):

Thermal Stress ◽

Heat Shock ◽

Heat Shock Response ◽

Early Stage ◽

Coregonus Clupeaformis ◽

Lake Whitefish ◽

Shock Response ◽

The Impact

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Se Alleviated Oxidative Stress-Mediated Complex Poisoning Mechanism in Pb-Treated Chicken Kidneys: Inflammation, Heat Shock Response, and Autophagy

10.21203/rs.3.rs-146251/v1 ◽

2021 ◽

Author(s):

Zhiying Miao ◽

Weikang Yu ◽

Yueyang Wang ◽

Xianhong Gu ◽

Xiaohua Teng

Keyword(s):

Oxidative Stress ◽

Heat Shock ◽

Protein Expression ◽

Heat Shock Response ◽

Potable Water ◽

Histological Structure ◽

Standard Diet ◽

Shock Response ◽

Mrna And Protein Expression ◽

Shock Proteins

Abstract Background: Lead (Pb) is a toxic environmental pollutant and can exerts toxicity in kidneys. It is known that selenium (Se) has an antagonistic effect on Pb poisoning. However, biological events during the process were not well understood in chicken kidneys.Methods: One hundred and eighty male Hyline chickens (7-day-old) were randomly divided into the control group (offering standard diet and potable water), the Se group (offering Na2SeO3-added standard diet and potable water), the Pb group (offering standard diet and (CH3OO)2Pb-added potable water), and the Pb+Se group (offering Na2SeO3-added standard diet and (CH3OO)2Pb-added potable water). On 30th, 60th, and 90th days, kidneys were removed to perform the studies of histological structure, oxidative stress indicators, cytokines, heat shock proteins, and autophagy in the chicken kidneys.Results: The experimental results indicated that Pb poisoning changed renal histological structure; decreased catalase, glutathione-s-transferase, and total antioxidative capacity activities; increased hydrogen peroxide content; induced mRNA and protein expression of heat shock proteins; inhibited interleukin (IL)-2 mRNA expression, and induced IL-4 and IL-12β mRNA expression; inhibited mammalian target of rapamycin mRNA and protein expression, and induced autophagy-related gene mRNA and protein expression in the chicken kidneys. Supplement of Se mitigated the above changes caused by Pb.Conclusion: Our research strengthens the evidence that Pb induced oxidative stress, inflammation, heat shock response, and autophagy and Se administration alleviated Pb poisoning through mitigating oxidative stress in the chicken kidneys.

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Activation of the heat shock response in a primary cellular model of motoneuron neurodegeneration-evidence for neuroprotective and neurotoxic effects

Cellular & Molecular Biology Letters ◽

10.2478/s11658-009-0002-8 ◽

2009 ◽

Vol 14 (2) ◽

Cited By ~ 38

Author(s):

Bernadett Kalmar ◽

Linda Greensmith

Keyword(s):

Cell Death ◽

Heat Shock ◽

Heat Shock Response ◽

Apoptotic Cell ◽

Experimental Conditions ◽

Pharmacological Agents ◽

Shock Response ◽

Induced Apoptosis ◽

Shock Proteins ◽

The Relationship

AbstractPharmacological up-regulation of heat shock proteins (hsps) rescues motoneurons from cell death in a mouse model of amyotrophic lateral sclerosis. However, the relationship between increased hsp expression and neuronal survival is not straightforward. Here we examined the effects of two pharmacological agents that induce the heat shock response via activation of HSF-1, on stressed primary motoneurons in culture. Although both arimoclomol and celastrol induced the expression of Hsp70, their effects on primary motoneurons in culture were significantly different. Whereas arimoclomol had survival-promoting effects, rescuing motoneurons from staurosporin and H2O2 induced apoptosis, celastrol not only failed to protect stressed motoneurons from apoptosis under same experimental conditions, but was neurotoxic and induced neuronal death. Immunostaining of celastrol-treated cultures for hsp70 and activated caspase-3 revealed that celastrol treatment activates both the heat shock response and the apoptotic cell death cascade. These results indicate that not all agents that activate the heat shock response will necessarily be neuroprotective.

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