Heat Shock Protein Research Articles

Viral proteins resolve the virus-vector conundrum during hemipteran-mediated transmission by subverting salicylic acid signaling pathway

Hemipteran insects transmit viruses when infesting plants, during which vectors activate salicylic acid (SA)-regulated antiviral defenses. How vector-borne plant viruses circumvent these antiviral defenses is largely unexplored. During co-infections of begomoviruses and betasatellites in plants, betasatellite-encoded βC1 proteins interfere with SA signaling and reduce the activation of antiviral resistance. βC1 inhibits SA-induced degradation of NbNPR3 (Nicotiana benthamiana nonexpressor of pathogenesis-related genes 3), a negative regulator of SA signaling. βC1 does not bind directly to NbNPR3, but regulates NbNPR3 degradation via heat shock protein 90s (NbHSP90s). NbHSP90s bind to both NbNPR3 and βC1 and suppress SA signaling. This viral success strategy appears to be conserved as it is also documented for viral proteins encoded by two aphid-borne viruses. Our findings reveal an exquisite mechanism that facilitates the persistence of vector-borne plant viruses and provide important insights into the intricacies of the virus life cycle.

Neuroprotective Effect of Natural Indole and β-carboline Alkaloids against Parkinson's Disease: An Overview.

Parkinson's disease (PD) is a devastating neurodegenerative condition that mostly damages dopaminergic neurons in the substantia nigra and impairs human motor function. Males are more likely than females to have PD. There are two main pathways associated with PD: one involves the misfolding of α-synuclein, which causes neurodegeneration, and the other is the catalytic oxidation of dopamine via MAO-B, which produces hydrogen peroxide that can cause mitochondrial damage. Parkin (PRKN), α-synuclein (SNCA), heat shock protein (HSP), and leucine-rich repeat kinase-2 (LRRK2) are some of the target areas for genetic alterations that cause neurodegeneration in Parkinson's disease (PD). Under the impact of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which is also important in Parkinson's disease (PD), inhibition of mitochondrial complex 1 results in enhanced ROS generation in neuronal cells. Natural products are still a superior option in the age of synthetic pharmaceuticals because of their lower toxicity and moderate side effects. A promising treatment for PD has been discovered using beta-carboline (also known as " β-carboline") and indole alkaloids. However, there are not many studies done on this particular topic. In the herbs containing β-carbolines and indoles, the secondary metabolites and alkaloids, β-carbolines and indoles, have shown neuroprotective and cognitive-enhancing properties. In this review, we have presented results from 18 years of research on the effects of indole and β-carboline alkaloids against oxidative stress and MAO inhibition, two key targets in PD. In the SAR analysis, the activity has been correlated with their unique structural characteristics. This study will undoubtedly aid researchers in looking for new PD treatment options.

Hydroxy-selenomethionine helps cows to overcome heat stress by enhancing antioxidant capacity and alleviating blood-milk barrier damage

Heat stress can lead to decreased feed intake, apoptosis of mammary epithelial cells, and decreased milk yield and quality. Selenium is an important element in the composition of at least 25 selenoproteins. Hydroxy-selenomethionine (HMSeBA; Andy Su Life Science Products Co., Ltd., Shanghai, China) is a novel organic selenium that has been shown to have a better deposition effect. However, whether HMSeBA alleviates damage to the mammary gland blood-milk barrier caused by heat stress and how this affects the performance of dairy cows remain largely unexplored. Therefore, 32 healthy Holstein cows with similar gestation days (150.41 ± 20.07 d), milk yield (36.15 ± 3.02 kg) and parity (3.25 ± 0.51) were selected and randomly divided into two total mixed rations with different selenium (Se) sources: sodium selenite (SSe) and HMSeBA. This study evaluated the outcomes of HMSeBA on antioxidant capacity, immunity, and blood-milk barrier damage in dairy cows during heat stress by collecting the samples of blood, rumen fluid and mammary gland biopsy. The experiment was conducted over 35 d, including a 5-day pre-feeding period and a 30-day experimental period. The temperature and humidity index (THI) were all above 80 throughout the experiment period. The results showed that HMSeBA decreased the respiratory rate (P < 0.001) and the content of inflammatory cytokines in the serum and increased the content of immune factors and antioxidant capacity (P < 0.05). In addition, HMSeBA reduced the expression of inflammatory cytokines and heat shock proteins in mammary gland (P < 0.05). Hematoxylin-eosin-stained pathological sections showed massive thickening of acinar walls and severe destruction of glandular structures in the SSe group, but the structure of the acinar mammary gland in the HMSeBA group was intact. Furthermore, HMSeBA promoted the expression of the phosphatidylinositol 3-kinase (PI3K, P < 0.001)/protein kinase B (AKT, P = 0.011)/mammalian target of rapamycin (mTOR, P = 0.008) pathway and improved the expression of zonula occludens-1 (ZO-1, P = 0.014) and occluding (OCLN, P = 0.012) in the mammary gland, suggesting less damage caused by heat stress to the blood-milk barrier. Our results demonstrated that HMSeBA can improve the antioxidant capacity and immunity of dairy cows and the expression of tight junction proteins in mammary gland to help alleviate the blood-milk barrier damage by heat stress, which could reduce the damage of heat stress on milk yield.

Causal relationship between ferroptosis-related gene HSPA5 and hepatocellular carcinoma: study based on mendelian randomization and mediation analysis.

To explore the causal relationship between ferroptosis-related gene heat shock protein A5 (HSPA5) and hepatocellular carcinoma (HCC). A two-sample Mendelian randomization (MR) design was employed to evaluate the causal relationships among HSPA5, regulatory T cells (Tregs), and liver cancer. Single nucleotide polymorphisms (SNPs) associated with HSPA5, HCC and Tregs were selected as instrumental variables through publicly available genome-wide association studies (GWAS) databases. MR analysis was used to assess the direct effect of HSPA5 on HCC, followed by two-step MR to analyze the potential mediating role of Tregs. Reverse MR analysis was conducted with liver cancer as the exposure and HSPA5 as the outcome. Inverse variance weighting (IVW) was the primary method for testing causal associations in all MR analyses. Robustness of the results was confirmed through MR Egger, weighted median, weighted mode, and simple mode methods. Heterogeneity of instrumental variables was evaluated using Cochrane's Q statistic, while pleiotropy was tested by MR-Egger intercept and MR-PRESSO, with leave-one-out sensitivity analysis performed for robustness. Data from The Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) were utilized to verify the expression levels of HSPA5 in liver cancer tissues and its correlation with Tregs to reveal the interaction mechanisms between HSPA5 and Tregs in HCC progression and their relationship with patient prognosis. MR analysis showed a positive correlation between elevated HSPA5 expression and liver cancer risk (all P<0.01), while reverse MR analysis found no statistically significant association between liver cancer and HSPA5 (P>0.05). HSPA5 expression was significantly correlated with Tregs function (all P<0.05), and the enrichment of Tregs in the liver cancer microenvironment was positively associated with liver cancer progression (all P<0.05). Mediation analysis indicated that Tregs accounted for 5.00% and 7.45% of the mediation effect between HSPA5 and liver cancer. TCGA and HPA database analysis revealed that both HSPA5 mRNA and protein expression levels were higher in liver cancer tissues compared to normal tissues, and high HSPA5 expression was significantly associated with poor patient prognosis. Immune infiltration analysis confirmed a significant positive correlation between HSPA5 and Tregs, with high Tregs infiltration closely related to HCC progression. Elevated HSPA5 expression is significantly associated with HCC development and poor prognosis. HSPA5 may promote HCC progression by regulating the function of Tregs in the tumor microenvironment.

Lysosomal damage triggers a p38 MAPK-dependent phosphorylation cascade to promote lysophagy via the small heat shock protein HSP27.

Maintenance of lysosomal integrity is essential for cell viability. Upon injury, lysosomes may be targeted for degradation via a selective form of autophagy known as lysophagy. The engulfment of a damaged lysosome by an autophagosome is mediated by the recruitment of adaptor proteins, including SQSTM1/p62. p62 promotes lysophagy via the formation of phase-separated condensates in a mechanism that is regulated by the heat shock protein HSP27. Here, we demonstrate a direct interaction between HSP27 and p62. We used structural modeling to predict the binding interface between HSP27 and p62 and identify several disease-associated mutations that map to this interface. We used proteomics to identify post-translational modifications of HSP27 that regulate HSP27 recruitment to stressed lysosomes, finding robust phosphorylation at several serine residues. Next, we characterized the upstream signaling mechanism leading to HSP27 phosphorylation and found that p38 mitogen-activated protein kinase (MAPK) and its effector kinase MAP kinase-activated protein kinase 2 (MK2) are activated upon lysosomal damage by the kinase mTOR and the production of intracellular reactive oxygen species (ROS). Increased ROS activates p38 MAPK, which in turn allows MK2-dependent phosphorylation of HSP27. Depletion of HSP27 or the inhibition of HSP27 phosphorylation alters the dynamics of p62 condensates on stressed lysosomes, significantly inhibiting p62-dependent lysophagy. Thus, we define a novel lysosomal quality control mechanism in which lysosomal injury triggers a p38 MAPK/MK2 signaling cascade promoting p62-dependent lysophagy. Further, this signaling cascade is activated by many cellular stressors, including oxidative and heat stress, suggesting that other forms of selective autophagy may be regulated by p38 MAPK/MK2/HSP27.

Tissue-specific, temporal, and core gene-dependent expression patterns of Hsp70s reveal functional allocation in Chlamys farreri under heat stress

Heat shock proteins 70 KDa (Hsp70s) engage in a broad spectrum of cellular functions in response to various stressors. Marine bivalves face substantial threats from the rising seawater temperature attributed to global warming. In the present study, expression patterns of Hsp70s in Zhikong scallop Chlamys farreri (CfHsp70s) were determined in embryos and larvae at all developmental stages, in healthy adult tissues, and across four various tissues exposed to high temperature for acute and chronic periods through in silico analysis. Spatiotemporal expressions suggested CfHsp70s performed specific functional differentiations in scallop's development and growth. Regulatory expression patterns of CfHsp70s, characterized by predominant down-regulation in the mantle, gill and hemocytes, as well as contrasting up-regulation in the heart, suggest differential functional allocation of CfHsp70s among tissues in response to heat stress. Particularly, a core set of 14 CfHsp70s, especially the nine members of the Hsp70B2s, characterized by gene expansion, intron-less structure, shorter gene length, preference for hydrophilic amino acids, and coordinated expression profiles, was predominantly responsible for the inducible up-regulations observed across all four tissue types. Collectively, the tissue-specific, temporal and core gene-dependent expression patterns of CfHsp70s illustrate the functional allocation and molecular evolution of Hsp70 family members in Zhikong scallops.

Exploring heat shock proteins as therapeutic targets for Parkinson’s disease

Exploring heat shock proteins as therapeutic targets for Parkinson’s disease

Regulation of NRF2 by Phosphoinositides and Small Heat Shock Proteins.

Phosphoinositides are coupled to NRF2 by PIPKIγ, and HSP27 is recruited and stabilizes NRF2, promoting stress-resistance.

Tandem mass tag-based proteomics reveals the antiepileptic mechanism of steroidal saponins from Anemarrhena asphodeloides in Kainic acid induced epileptic rat model.

Epilepsy (EP) is one of the most common neurological diseases in the world. Anemarrhena asphodeloides Bunge. (AA), as a typical heat-cleaning medicine, has been proven to possess the antiepileptic effect in clinical and experimental studies. Anemarrhena asphodeloides steroidal saponins (AAS) are main components. However, the therapeutic effects and underlying mechanisms of AAS against EP are not been fully elucidated. In this study, 63 steroidal saponins were discovered in AAS by UPLC-Q-TOF/MS analysis. Pharmacological and behavioral analysis demonstrated that AAS could significantly lower the Racine classification and reduce the frequency of generalized spike rhythm the rate of tetanic seizures in kainic acid-induced epileptic rats. Hematoxylin and eosin and Nissl staining-indicated AAS could significantly improve hippocampal injury and neuron loss in epileptic rats. TMT proteomic analysis discovered 26 different expressed proteins (DEPs), which were identified as the rescue proteins. After bioinformatic analysis, Heat Shock Protein 90 Alpha Family Class B Member 1 (Hsp90ab1) and Tyrosine 3-Monooxygenase (Ywhab) were screened as key DEPs and verified by western blotting. AAS could significantly inhibited the up-regulation of Hsp90ab1 and Ywhab in EP rats; these two proteins might be the key targets of AAS in treating EP.

Homology Modelling and Molecular Docking of Some Natural Compounds as Inhibitors of Anopheles gambiae Heat Shock Protein 70KDa and Bifunctional Glutamyl/prolyl-tRNA Synthetase

Homology Modelling and Molecular Docking of Some Natural Compounds as Inhibitors of Anopheles gambiae Heat Shock Protein 70KDa and Bifunctional Glutamyl/prolyl-tRNA Synthetase

Extracellular Hsp90 of Candida albicans contributes to the virulence of the pathogen by activating the NF-κB signaling pathway and inducing macrophage pyroptosis

Strategies aimed at targeting fungal extracellular heat shock protein 90 (eHsp90) using vaccines and antibodies have demonstrated encouraging potential in the prevention and management of invasive fungal diseases (IFDs). However, the precise underlying mechanism by which eHsp90 contributes to the heightened virulence of Candida albicans (C. albicans) remains an enigma, awaiting further elucidation. In our current research, we have found that the 47-kDa fragment of C. albicans Hsp90 (CaHsp90), which serves as the primary antigenic determinant, is not degraded within C. albicans cells. Moreover, we have discovered that extracellular CaHsp90 (eCaHsp90) is derived from the components of lysed C. albicans cells. We also generated recombinant CaHsp90 in Escherichia coli, and found that eCaHsp90 spreads beyond the initial C. albicans colonization site, thereby enhancing the overall virulence of the organism. Our results further clarify that eCaHsp90 activates the nuclear factor kappa-B (NF-κB) signaling pathway and upregulates the expression of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3). This upregulation results in the activation of Gasdermin D (GSDMD) and subsequent macrophage pyroptosis, ultimately increasing the virulence of C. albicans. This study provides valuable insights into the mechanism by which eCaHsp90 contributes to the virulence of C. albicans, offering a pharmacological basis for antifungal strategies targeting fungal eHsp90.

Effects of intensive and conventional farming on oxidative stress and meat quality biomarkers in holstein and simmental cattle

This study investigates the intricate factors influencing meat quality, including breed, rearing conditions, and processing, with a primary focus on oxidative stress in Holstein Friesian and Simmental cattle within conventional and intensive production systems. A notable difference in oxidative stress was found between animals subjected to intensive-farming versus conventional practices, with Holstein cattle showing a more pronounced antioxidant gene response than Simmental. The analysis revealed that intensive rearing conditions resulted in increased DNA repair activity and expression of stress-response proteins like heat shock proteins, suggestive of greater cellular damage and an adaptive stress response. Muscle tissue analyses, revealed a clear distinction in gene expression associated with meat quality between the breeds and the type of farming system. A negative correlation emerged between oxidative stress levels and genes related to muscle development, which affects meat quality. Intensive farming conditions altered the expressions of apoptotic proteins, impacting meat quality at the molecular level. These results underscore the profound effect rearing conditions have on meat quality, driven by stress-related molecular responses. This highlights the need for further research into the influence of husbandry practices on animal welfare and meat quality, with the intention of developing strategies to mitigate the negative consequences of intensive-farming.

Perfusate Biomarkers of DCD Cardiac Graft Quality Identified With Proteomics: Studies in an Isolated Rat Heart Model.

Heart transplantation with donation after circulatory death (DCD) enhances cardiac graft availability, but exposes hearts to potentially damaging conditions, such as warm ischemia. Normothermic machine perfusion (NMP), used for graft transportation, allows biomarker determination in perfusate. Using our isolated, rat heart model of DCD, we evaluated potent. Isolated, perfused adult male Wistar rat hearts (n = 5/group) underwent different warm ischemic durations to simulate DCD, followed by reperfusion to simulate NMP. Perfusate samples were collected after 10 min reperfusion, and proteins were analyzed using mass spectrometry. Cardiac recovery was evaluated after 60 min reperfusion. The relationship between perfusate proteins and cardiac recovery was investigated. Cardiac recovery decreased with increasing ischemic duration. Principal component analysis of perfusate proteins demonstrated segregation by ischemic group. Several proteins demonstrated an On-Off pattern, and correlated with key outcome measurements. Other proteins were released by all hearts and were confirmed as predictors of cardiac recovery, for example, heat shock protein 70 and valosin-containing protein (area under the curve [AUC] = 0.962-0.968, respectively; P < 0.05 for all). Additionally, proteins such as glycogen phosphorylase, muscle associated (AUC = 0.9632; P < 0.05) showed potential as novel biomarkers for evaluating cardiac graft quality, unlike lactate release after 10 min of reperfusion (AUC = 0.60). Multiple perfusate proteins, such as heat shock protein 70, valosin-containing protein, or glycogen phosphorylase, muscle associated, released during early reperfusion are promising as biomarkers for assessing graft quality during NMP. Perfusate proteins, as biomarkers, offer the possibility of both rapid immune detection and out-of-hospital implementation, and may provide valuable information about graft quality, especially when profiled with serial sampling during NMP.

HSP90 Enhances Mitophagy to Improve the Resistance of Car-Diomyocytes to Heat Stress in Wenchang Chickens.

Heat shock protein 90 (HSP90) is recognized for its protective effects against heat stress damage; however, the specific functions and underlying molecular mechanisms of HSP90 in heat-stressed cardiomyocytes remain largely unexplored, particularly in tropical species. In our study, Wenchang chickens (WCCs) were classified into two groups: the heat stress survival (HSS) group and the heat stress death (HSD) group, based on their survival following exposure to heat stress. Heat stress resulted in significant cardiomyocyte damage, mitochondrial dysfunction, and apoptosis in the HSD group, while the damage was less pronounced in the HSS group. We further validated these findings in primary cardiomyocytes derived from Wenchang chickens (PCWs). Additionally, heat stress was found to upregulate Pink1/Parkin-mediated mitophagy, which was accompanied by an increase in HSP90 expression in both cardiomyocytes and PCWs. Our results demonstrated that HSP90 overexpression enhances PINK1/Parkin-mediated mitophagy, ultimately inhibiting apoptosis and oxidative stress in heat-stressed PCWs. However, the application of Geldanamycin (GA) reversed these effects. Notably, we discovered that HSP90 interacts with Beclin-1 through mitochondrial translocation and directly regulates mitophagy levels in PCWs. In summary, we have elucidated a novel role for HSP90 and mitophagy in regulating heat stress-induced acute cardiomyocyte injury.

Are There Non-Invasive Biomarker(s) That Would Facilitate the Detection of Ovarian Torsion? A Systematic Review and Meta-Analysis.

Ovarian torsion (OT) is a rare gynaecological emergency that requires a prompt diagnosis for optimal patient management. To determine whether there were any biomarkers suitable for the non-invasive detection of OT, two independent reviewers performed systematic searches of five literature databases (PubMed, Medline, Scopus, Cochrane, and CINAHL) from inception until October 1st, 2023. Following the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, the search included patients with OT that had quantified biomarker expression with no age, geographical location, publication date, language, or setting restrictions. Articles were excluded if OT was found incidentally, was based on qualitative analyses, or were not primary research articles. Full texts of 23 selected articles were assessed for risk of bias and quality assurance using a modified Newcastle-Ottawa Scale (NOS) for clinical studies and SYRCLE's risk of bias tool for the assessment of pre-clinical (animal) studies. A total of 11 articles described studies on animals and all described serum biomarkers comparing results between OT versus a sham operation, a control group, or readings before and after OT. Ischaemia-modified albumhumin (IMA), serum D-dimer (s-DD), heat shock protein-70 (hsp-70), Pentraxin-3 (PTX3), and c-reactive protein (CRP) each showed the most promise, with p-values for the difference between OT and control groups achieving ≤ 0.001. In studies of humans, the biomarkers ranged from 16.4 to 92.3% sensitivity and 77-100% specificity. The most promising biomarkers for the early prediction of OT in patients included s-DD, interleukin-6 (IL-6), IMA, and tumour necrosis factor-alpha (TNF-α). Signal peptide, CUB domain, and EGF-like domain-containing 1 (SCUBE1) had a high specificity at 93.3%, second only to s-DD and a positive likelihood ratio (LR) > 10. IMA was the only other biomarker that also had a positive LR > 10, making it a promising diagnostic biomarker. The studies identified by this systematic literature review each analysed small patient groups but IMA, DD, and SCUBE1 nevertheless showed promise as serum biomarkers with a pooled LR > 10. However, further well-designed studies are needed to identify and evaluate individual markers or diagnostic panels to help clinicians manage this important organ-threatening condition.

Effective Antitumor Synergistic Treatment with Fiber-Photothermal Therapy and Heat Shock Protein Inhibitors.

Effective treatment of malignant tumors remains a thorny issue in current medicine. As a new type of anticancer strategy, photothermal therapy (PTT) has attracted tremendous attention due to its favorable therapeutic effectiveness, high spatial-temporal controllability, and low occurrence of side effects. However, the efficacy of PTT is significantly reduced due to the limited penetration of light and heat-induced overexpression of heat shock protein (Hsp). Herein, we propose an antitumor synergistic therapy that combines fiber-optic PTT and Hsp inhibitors. A rare-earth-doped optical fiber was used as the PTT actuator, and the Hsp inhibitor AT533 was loaded on the fiber surface by use of a hydrogel layer. PTT fibers can be guided to reach tumor lesions directly without being subject to the light penetration limit. The Hsp inhibitor can be released upon the softening of the hydrogel layer under photoheating to deactivate Hsp in the tumor and thus reduce the resistance of the tumor to PTT. This synergistic treatment enhanced the effect of PTT and successfully eradicated tumors in colorectal cancer (CRC) xenograft mouse models, providing a feasible way to realize antitumor and antirecurrence treatment. More importantly, the success of the synergistic treatment of PTT and Hsp inhibition opens new avenues for the development of multimodal and multitype synergistic fiber-optic treatments, which offer pronounced enhancement of therapeutic effectiveness for treating cancer.

Heat shock protein HSPA8 impedes hemin-induced cellular-toxicity in liver

Accumulation of hemin in cells, tissues, and organs is one of the major pathological conditions linked to hemolytic diseases like malaria. Pro-oxidant hemin confers high toxicity following its accumulation. We tested the cellular toxicity of hemin on HepG2 cells by exploring modulation in various cellular characteristics. Hemin reduces the viability of HepG2 cells and brings about visible morphological changes. Hemin causes perforations on the surface of HepG2 cells observed through SEM. Hemin leads to the extracellular release of liver enzymes and reduces the wound-healing potential of HepG2 cells. Hemin leads to the fragmentation of HepG2 DNA, arrests the cell cycle progression in the S-phase and induces apoptosis in these cells. Western blot analysis revealed that hemin triggers both the extrinsic and intrinsic pathways of apoptosis in HepG2 cells. We have already shown that the cytoprotective protein HSPA8 can polymerize hemin and minimize its toxicity. Similar experiments with hemin in the presence and absence of HSPA8 showed that HSPA8 reverses all the tested toxic effects of hemin on HepG2 cells. The protection from hemin toxicity in HepG2 cells appeared to be due to the extracellular polymerization of hemin by HSPA8.

Extracellular Hsp70 and Circulating Endometriotic Cells as Novel Biomarkers for Endometriosis.

Stress-inducible heat shock protein 70 (Hsp70), which functions as a molecular chaperone and is frequently overexpressed in different cancer cell types, is present on the cell surface of tumor cells and is actively released into the circulation in free and extracellular lipid vesicle-associated forms. Since the exact pathomechanism of endometriosis has not yet been elucidated (although it has been associated with the development of endometrial and ovarian cancer), we asked whether extracellular Hsp70 and circulating endometriotic cells (CECs) reflect the presence and development of endometriosis. Therefore, circulating levels of free and lipid microvesicle-associated Hsp70 were measured using the Hsp70-exo ELISA, and the presence of circulating CECs in the peripheral blood of patients with endometriosis was determined using membrane Hsp70 (mHsp70) and EpCAM monoclonal antibody (mAb)-based bead isolation approaches. Isolated CECs were further characterized by immunofluorescence using reagents directed against cytokeratin (epithelial marker), CD45 (leukocyte marker), CD105/CD44 (mesenchymal stemness markers) and by comparative RNA analysis. Similar to the situation in patients with cancer, the levels of circulating Hsp70 were elevated in the blood of patients with histologically proven endometriosis compared to a healthy control cohort, with significantly elevated Hsp70 levels in endometriosis patients with lesions outside the uterine cavity. Moreover, CECs could be isolated using the cmHsp70.1 mAb-based, and to a lesser extent EpCAM mAb-based, bead approach in all patients with endometriosis, with the highest counts obtained using the mHsp70-targeting procedure in patients with extra-uterine involvement. The longevity in cell culture and the expression of the cytokeratins CD105 and CD44, together with differentially expressed genes related to epithelial-to-mesenchymal transition (EMT), revealed similarities between mHsp70-expressing CECs and circulating tumor cells (CTCs) and suggest a mesenchymal stem cell origin. These findings support the involvement of mHsp70-positive stem cell-like cells in the development of endometriotic lesions. In summary, elevated levels of Hsp70 and CECs in the circulation could serve as liquid biopsy markers for endometriosis with extra-uterine involvement and help to elucidate the underlying pathomechanism of the disease.

EGFR-mediated HSP70 phosphorylation facilitates PCNA association with chromatin and DNA replication.

Efficient DNA replication requires highly coordinated programs for the timely recruitment of protein complexes to DNA replication forks. Defects in this process result in replication stress, which in turn activates cell cycle checkpoints, suppresses cell proliferation and induces apoptosis. In response to persistent cell growth signals that speed up DNA replication processes, cells accelerate the recruitment of DNA replication proteins to avoid DNA replication stress. The mechanisms by which cell growth signals induce processes to facilitate the recruitment of DNA replication proteins onto the replication sites remain unclear. Here, we report that the epidermal growth factor receptor (EGFR) phosphorylates heat shock protein 70 (HSP70) for DNA replication. Such a modification promotes nuclear localization and chromatin association of HSP70, which interacts with the DNA replication coordinator, proliferating cell nuclear antigen (PCNA). HSP70 subsequently facilitates the loading of PCNA onto chromatin. Knockdown or chemical inhibition of HSP70 suppresses PCNA association with chromatin and impairs DNA synthesis and Okazaki fragment maturation, leading to replicative DNA double-strand breaks and apoptosis. Furthermore, chemical inhibition of HSP70 potentiates EGFR-tyrosine kinase inhibitor-induced tumor reduction in vivo. This work expands our understanding of oncogenesis-induced DNA replication processes and provides a foundation for improved treatments for EGFR-mutated lung cancer by simultaneously targeting HSP70.

The Effect of Variegated Grasshopper Meal (Zonocerous variegatus) on Growth, Nutrient Utilization and Gene Expression Study in Juvenile Clarias gariepinus (Burchell, 1822)

Over the years there has been research on how to improve fish yield. This study investigated the effects of variegated grasshopper meal (Zonocerous variegatus) on growth performance, nutrient utilization, and gene expressions in juvenile Clarias gariepinus (African catfish). The variegated grasshopper meal diets (VGDMs) were incorporated with the other feed ingredients at 25% (VGDM1), 50% (VGDM2), 75% (VGDM2), and 100% (VGDM3) diets while the remaining group served as control. Growth performance, nutrient utilization, and gene expression study were evaluated. The mRNA expression of Growth hormone (GH), Heat Shock Protein (HSP70), Melatonin (MEL 1C), tumour necrosis factor-alpha (TNF-α), and interleukin 1 beta (IL-1β) were investigated in the liver and muscle of C. gariepinus fed with varying doses of grasshopper meals (VGDMs) using reverse transcriptase–polymerase chain reaction. There were significant (p&gt;0.05) variations in all parameters in all the treatments. There was a significant upregulation (p&lt;0.05) in the gene expression of GH, HSP70, MEL 1C, and TNF-α in VGDM1 compared to control in both tissue groups. In addition, there was significant downregulation (p&lt;0.05) in interleukin 1 (IL-1β) gene expression in liver VGDM2. This study suggests that dietary variations involving VGMD have the potential to boost growth and improve the immune responses of this fish species.