RESUMO
Currently, bifunctional agents with vasodilation and ameliorated vascular remodeling effects provide more advantages for the treatment of pulmonary arterial hypertension (PAH). In this study, we first screened the hit 1 with heat shock protein 110 (Hsp110) inhibition effect from our in-house compound library with soluble guanylate cyclase (sGC) activity. Subsequently, a series of novel bisamide derivatives were designed and synthesized as Hsp110/sGC dual-target regulators based on hit 1. Among them, 17i exhibited optimal Hsp110 and sGC molecular activities as well as remarkable cell malignant phenotypes inhibitory and vasodilatory effects in vitro. Moreover, compared to riociguat, 17i showed superior efficacy in attenuating pulmonary vascular remodeling and right ventricular hypertrophy via Hsp110 suppression in hypoxia-induced PAH rat models (i.g.). Notably, our study successfully demonstrated that the simultaneous regulation of Hsp110 and sGC dual targets was a novel and feasible strategy for PAH therapy, providing a promising lead compound for anti-PAH drug discovery.
Assuntos
Proteínas de Choque Térmico HSP110 , Guanilil Ciclase Solúvel , Animais , Guanilil Ciclase Solúvel/metabolismo , Humanos , Ratos , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP110/antagonistas & inibidores , Ratos Sprague-Dawley , Descoberta de Drogas , Hipertensão Arterial Pulmonar/tratamento farmacológico , Hipertensão Arterial Pulmonar/metabolismo , Masculino , Relação Estrutura-Atividade , Hipertensão Pulmonar/tratamento farmacológico , Remodelação Vascular/efeitos dos fármacosRESUMO
Activated B-cell-like diffuse large B-cell lymphoma (ABC-DLBCL) is driven by aberrant activation of the B-cell receptor (BCR) and the TLR/MyD88 signaling pathways. The heat-shock protein HSP110 is a candidate for their regulation as it stabilizes MyD88. However, its role in overall BCR signaling remains unknown. Here, we used first-in-class HSP110 inhibitors to address this question. HSP110 inhibitors decreased the survival of several ABC-DLBCL cell lines in vitro and in vivo, and reduced the phosphorylation of BCR signaling kinases, including BTK and SYK. We identified an interaction between HSP110 and SYK and demonstrated that HSP110 promotes SYK phosphorylation. Finally, the combination of the HSP110 inhibitor with the PI3K inhibitor copanlisib decreases SYK/BTK and AKT phosphorylation synergistically, leading to suppression of tumor growth in cell line xenografts and strong reduction in patient-derived xenografts. In conclusion, by regulating the BCR/TLR signaling pathway, HSP110 inhibitors are potential drug candidates for ABC-DLBCL patients.
Assuntos
Proteínas de Choque Térmico HSP110 , Linfoma Difuso de Grandes Células B , Receptores de Antígenos de Linfócitos B , Transdução de Sinais , Quinase Syk , Ensaios Antitumorais Modelo de Xenoenxerto , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Quinase Syk/antagonistas & inibidores , Quinase Syk/metabolismo , Humanos , Fosforilação/efeitos dos fármacos , Animais , Camundongos , Receptores de Antígenos de Linfócitos B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas de Choque Térmico HSP110/metabolismo , Pirimidinas/farmacologia , Linhagem Celular Tumoral , Células Tumorais Cultivadas , Camundongos SCID , QuinazolinasRESUMO
BACKGROUND: Primary mediastinal B-cell lymphoma (PMBL) and classical Hodgkin lymphoma (cHL) are distinct hematological malignancies of B-cell origin that share many biological, molecular, and clinical characteristics. In particular, the JAK/STAT signaling pathway is a driver of tumor development due to multiple recurrent mutations, particularly in STAT6. Furthermore, the XPO1 gene that encodes exportin 1 (XPO1) shows a frequent point mutation (E571K) resulting in an altered export of hundreds of cargo proteins, which may impact the success of future therapies in PMBL and cHL. Therefore, targeted therapies have been envisioned for these signaling pathways and mutations. METHODS: To identify novel molecular targets that could overcome the treatment resistance that occurs in PMBL and cHL patients, we have explored the efficacy of a first-in-class HSP110 inhibitor (iHSP110-33) alone and in combination with selinexor, a XPO1 specific inhibitor, both in vitro and in vivo. RESULTS: We show that iHSP110-33 decreased the survival of several PMBL and cHL cell lines and the size of tumor xenografts. We demonstrate that HSP110 is a cargo of XPO1wt as well as of XPO1E571K. Using immunoprecipitation, proximity ligation, thermophoresis and kinase assays, we showed that HSP110 directly interacts with STAT6 and favors its phosphorylation. The combination of iHSP110-33 and selinexor induces a synergistic reduction of STAT6 phosphorylation and of lymphoma cell growth in vitro and in vivo. In biopsies from PMBL patients, we show a correlation between HSP110 and STAT6 phosphorylation levels. CONCLUSIONS: These findings suggest that HSP110 could be proposed as a novel target in PMBL and cHL therapy.
Assuntos
Proteína Exportina 1 , Doença de Hodgkin , Carioferinas , Receptores Citoplasmáticos e Nucleares , Humanos , Carioferinas/antagonistas & inibidores , Carioferinas/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Animais , Camundongos , Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/patologia , Doença de Hodgkin/metabolismo , Doença de Hodgkin/genética , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/metabolismo , Linfoma de Células B/patologia , Linfoma de Células B/genética , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP110/genética , Linhagem Celular Tumoral , Neoplasias do Mediastino/tratamento farmacológico , Neoplasias do Mediastino/metabolismo , Neoplasias do Mediastino/patologia , Neoplasias do Mediastino/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Triazóis/farmacologia , Triazóis/uso terapêutico , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Feminino , Fator de Transcrição STAT6/metabolismo , Terapia de Alvo MolecularRESUMO
Sse1 is a cytosolic Hsp110 molecular chaperone of yeast, Saccharomyces cerevisiae. Its multifaceted roles in cellular protein homeostasis as a nucleotide exchange factor (NEF), as a protein-disaggregase and as a chaperone linked to protein synthesis (CLIPS) are well documented. In the current study, we show that SSE1 genetically interacts with IRE1 and HAC1, the endoplasmic reticulum-unfolded protein response (ER-UPR) sensors implicating its role in ER protein homeostasis. Interestingly, the absence of this chaperone imparts unusual resistance to tunicamycin-induced ER stress which depends on the intact Ire1-Hac1 mediated ER-UPR signaling. Furthermore, cells lacking SSE1 show inefficient ER-stress-responsive reorganization of translating ribosomes from polysomes to monosomes that drive uninterrupted protein translation during tunicamycin stress. In consequence, the sse1Δ strain shows prominently faster reversal from ER-UPR activated state indicating quicker restoration of homeostasis, in comparison to the wild-type (WT) cells. Importantly, Sse1 plays a critical role in controlling the ER-stress-mediated cell division arrest, which is escaped in sse1Δ strain during chronic tunicamycin stress. Accordingly, sse1Δ strain shows significantly higher cell viability in comparison to WT yeast imparting the stark fitness following short-term as well as long-term tunicamycin stress. These data, all together, suggest that cytosolic chaperone Sse1 is an important modulator of ER stress response in yeast and it controls stress-induced cell division arrest and cell death during overwhelming ER stress induced by tunicamycin.
Assuntos
Estresse do Retículo Endoplasmático , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Tunicamicina , Resposta a Proteínas não Dobradas , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Tunicamicina/farmacologia , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP110/genética , Transdução de Sinais , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/genética , Biossíntese de Proteínas , Chaperonas Moleculares/metabolismo , Chaperonas Moleculares/genética , Retículo Endoplasmático/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Glicoproteínas de Membrana , Proteínas Repressoras , Proteínas de Choque Térmico HSP70RESUMO
INTRODUCTION: Gastric cancer (GC) is one of the leading causes of cancer-related death worldwide. Recently, targeted therapies including PD1 (programmed cell death 1) antibodies have been used in advanced GC patients. However, identifying new biomarker for immunotherapy is still urgently needed. The objective of this study is to unveil the immune evasion mechanism of GC cells and identify new biomarkers for immune checkpoint blockade therapy in patients with GC. METHODS: Coimmunoprecipitation and meRIP were performed to investigate the mechanism of immune evasion of GC cells. Cocuture system was established to evaluate the cytotoxicity of cocultured CD8+ T cells. The clinical significance of HSPA4 upregulation was analyzed by multiplex fluorescent immunohistochemistry staining in GC tumor tissues. RESULTS: Histone acetylation causes HSPA4 upregulation in GC tumor tissues. HSPA4 upregulation increases the protein stability of m6A demethylase ALKBH5. ALKBH5 decreases CD58 in GC cells through m6A methylation regulation. The cytotoxicity of CD8+ T cells are impaired and PD1/PDL1 axis is activated when CD8+ T cells are cocultured with HSPA4 overexpressed GC cells. HSPA4 upregulation is associated with worse 5-year overall survival of GC patients receiving only surgery. It is an independent prognosis factor for worse survival of GC patients. In GC patients receiving the combined chemotherapy with anti-PD1 immunotherapy, HSPA4 upregulation is observed in responders compared with non-responders. CONCLUSION: HSPA4 upregulation causes the decrease of CD58 in GC cells via HSPA4/ALKBH5/CD58 axis, followed by PD1/PDL1 activation and impairment of CD8+ T cell's cytotoxicity, finally induces immune evasion of GC cells. HSPA4 upregulation is associated with worse overall survival of GC patients with only surgery. Meanwhile, HSPA4 upregulation predicts for better response in GC patients receiving the combined immunotherapy.
Assuntos
Linfócitos T CD8-Positivos , Neoplasias Gástricas , Humanos , Linfócitos T CD8-Positivos/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Regulação para Cima , Evasão da Resposta Imune , Quimioterapia Combinada , Proteínas de Choque Térmico HSP110/metabolismo , Homólogo AlkB 5 da RNA Desmetilase/metabolismoRESUMO
With the global rise in cancer incidence and mortality rates, research on the topic has become increasingly urgent. Among the significant players in this field are heat shock proteins (HSPs), particularly HSPA4 from the HSP70 subfamily, which has recently garnered considerable interest for its role in cancer progression. However, despite numerous studies on HSPA4 in specific cancer types, a comprehensive analysis across all cancer types is lacking. This study employs various bioinformatics techniques to delve into the role of HSPA4 in pan-cancer. Our objective is to assess its potential in clinical diagnosis, prognosis, and as a future molecular target for therapy. The research findings reveal significant differences in HSPA4 expression across different cancer types, suggesting its diagnostic value and close association with cancer staging and patient survival rates. Furthermore, genetic variations and methylation status of HSPA4 play critical roles in tumorigenesis. Lastly, the interaction of HSPA4 with immune cells is linked to the tumor microenvironment (TME) and immunotherapy. In summary, HSPA4 emerges as a promising cancer biomarker and a vital member of the HSPs family, holding potential applications in diagnosis, prognosis, and immunotherapy.
Assuntos
Proteínas de Choque Térmico HSP110 , Neoplasias , Humanos , Proteínas de Choque Térmico HSP110/genética , Proteínas de Choque Térmico HSP110/metabolismo , Prognóstico , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/terapia , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico/genética , Imunoterapia , Microambiente Tumoral/genéticaRESUMO
Glioma is still an incurable disease with high invasiveness. Heat shock 70 kDa protein 4 (HSPA4) is a member of the HSP110 family, and is associated with the development and progression of various cancers. In the current study, we assessed the expression of HSPA4 in clinical samples, and found that HSPA4 was up-regulated in glioma tissues and correlated with tumor recurrence and grade. Survival analyses demonstrated that glioma patients with high HSPA4 expression had lower overall survival and disease-free survival times. In vitro knockdown of HSPA4 inhibited glioma cell proliferation, mediated cell cycle arrest at G2 phase and apoptosis, and reduced the migration ability. In vivo, the growth of HSPA4-knockdown xenografts was markedly suppressed compared to the tumors formed by HSPA4-positive control cells. Additionally, Gene set enrichment analyses disclosed that HSPA4 was associated with the PI3K/Akt signaling pathway. The regulatory effect of the AKT activator SC79 on cell proliferation and apoptosis was suppressed by HSPA4 knockdown, indicating that HSPA4 is capable of promoting glioma development. In summary, these data showed that HSPA4 is likely to play a pivotal role in the progression of glioma, and consequently may be a promising therapeutic target for glioma therapy.
Assuntos
Glioma , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Glioma/genética , Glioma/patologia , Pontos de Checagem do Ciclo Celular , Proliferação de Células , Linhagem Celular Tumoral , Apoptose , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica , Proteínas de Choque Térmico HSP110/genética , Proteínas de Choque Térmico HSP110/metabolismoRESUMO
BACKGROUND: Pulmonary arterial hypertension (PAH) is a progressive and devastating disease characterized by pulmonary vascular remodeling which is associated with the malignant phenotypes of pulmonary vascular cells. Recently, the effects of heat shock protein 110 (Hsp110) in human arterial smooth muscle cells were reported. However, the underlying roles and mechanisms of Hsp110 in human pulmonary arterial endothelial cells (HPAECs) that was disordered firstly at the early stage of PAH remain unknown. METHODS: In this research, the expression of Hsp110 in PAH human patients and rat models was investigated, and the Hsp110 localization was determined both in vivo and in vitro. The roles and mechanism of elevated Hsp110 in excessive cell proliferation and migration of HPAECs were assessed respectively exposed to hypoxia. Small molecule inhibitors targeting Hsp110-STAT3 interaction were screened via fluorescence polarization, anti-aggregation and western blot assays. Moreover, the effects of compound 6 on HPAECs abnormal phenotypes in vitro and pulmonary vascular remodeling of hypoxia-indued PAH rats in vivo by interrupting Hsp110-STAT3 interaction were evaluated. RESULTS: Our studies demonstrated that Hsp110 expression was increased in the serum of patients with PAH, as well as in the lungs and pulmonary arteries of PAH rats, when compared to their respective healthy subjects. Moreover, Hsp110 levels were significantly elevated in HPAECs under hypoxia and mediated its aberrant phenotypes. Furthermore, boosted Hsp110-STAT3 interaction resulted in abnormal proliferation and migration via elevating p-STAT3 and c-Myc in HPAECs. Notably, we successfully identified compound 6 as potent Hsp110-STAT3 interaction inhibitor, which effectively inhibited HPAECs proliferation and migration, and significantly ameliorated right heart hypertrophy and vascular remodeling of rats with PAH. CONCLUSIONS: Our studies suggest that elevated Hsp110 plays a vital role in HPAECs and inhibition of the Hsp110-STAT3 interaction is a novel strategy for improving vascular remodeling. In addition, compound 6 could serve as a promising lead compound for developing first-in-class drugs against PAH.
Assuntos
Hipertensão Arterial Pulmonar , Humanos , Ratos , Animais , Hipertensão Arterial Pulmonar/metabolismo , Proteínas de Choque Térmico HSP110/metabolismo , Remodelação Vascular , Células Endoteliais/metabolismo , Hipertensão Pulmonar Primária Familiar , Artéria Pulmonar/patologia , Hipóxia/metabolismo , Miócitos de Músculo Liso/metabolismo , Proliferação de Células , Fator de Transcrição STAT3/metabolismoRESUMO
HSP70 and its evolutionarily diverged co-chaperone HSP110, forms an important node in protein folding cascade. How these proteins maintain the aggregation-prone proteome of malaria parasite in functional state remains underexplored, in contrast to its human orthologs. In this study, we have probed into conformational dynamics of plasmodial HSP70 and HSP110 through multiple µs MD-simulations (ATP-state) and compared with their respective human counterparts. Simulations covered sampling of 3.4 and 2.8 µs for HSP70 and HSP110, respectively, for parasite and human orthologs. We provide a comprehensive description of the dynamic behaviors that characterize the systems and also introduce a parameter for quantifying protein rigidity. For HSP70, the interspecies comparison reveals enhanced flexibility in IA and IB subdomain within the conserved NBD, lesser solvent accessibility of the interdomain linker and distinct dynamics of the SBDß of Pf HSP70 in comparison to Hs HSP70. In the case of HSP110, notable contrast in the dynamics of NBD, SBDß and SBDα was observed between parasite and human ortholog. Although HSP70 and HSP110 are members of the same superfamily, we identified specific differences in the subdomain contacts in NBD, linker properties and interdomain movements in their human and parasite orthologs. Our study suggests that differences in conformational dynamics may translate into species-specific differences in the chaperoning activities of HSP70-HSP110 in the parasite and human, respectively. Dynamical features of Pf HSP70-HSP110 may contribute to the maintenance of proteostasis in the parasite during its intracellular survival in the host.
Assuntos
Proteínas de Choque Térmico HSP110 , Plasmodium , Humanos , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Dobramento de ProteínaRESUMO
Perturbations in the native structure, often caused by stressing cellular conditions, not only impair protein function but also lead to the formation of aggregates, which can accumulate in the cell leading to harmful effects. Some organisms, such as plants, express the molecular chaperone HSP100 (homologous to HSP104 from yeast), which has the remarkable capacity to disaggregate and reactivate proteins. Recently, studies with animal cells, which lack a canonical HSP100, have identified the involvement of a distinct system composed of HSP70/HSP40 that needs the assistance of HSP110 to efficiently perform protein breakdown. As sessile plants experience stressful conditions more severe than those experienced by animals, we asked whether a plant HSP110 could also play a role in collaborating with HSP70/HSP40 in a system that increases the efficiency of disaggregation. Thus, the gene for a putative HSP110 from the cereal Sorghum bicolor was cloned and the protein, named SbHSP110, purified. For comparison purposes, human HsHSP110 (HSPH1/HSP105) was also purified and investigated in parallel. First, a combination of spectroscopic and hydrodynamic techniques was used for the characterization of the conformation and stability of recombinant SbHSP110, which was produced folded. Second, small-angle X-ray scattering and combined predictors of protein structure indicated that SbHSP110 and HsHSP110 have similar conformations. Then, the chaperone activities, which included protection against aggregation, refolding, and reactivation, were investigated, showing that SbHSP110 and HsHSP110 have similar functional activities. Altogether, the results add to the structure/function relationship study of HSP110s and support the hypothesis that plants have multiple strategies to act upon the reactivation of protein aggregates.
Assuntos
Proteínas de Saccharomyces cerevisiae , Sorghum , Animais , Humanos , Sorghum/metabolismo , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/metabolismo , Dobramento de Proteína , Saccharomyces cerevisiae , Proteínas de Choque Térmico HSP110/genética , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismoRESUMO
Apg2, one of the three cytosolic Hsp110 chaperones in humans, supports reactivation of unordered and ordered protein aggregates by Hsc70 (HspA8). Together with DnaJB1, Apg2 serves to nucleate Hsc70 molecules into sites where productive entropic pulling forces can be developed. During aggregate reactivation, Apg2 performs as a specialized nucleotide exchange factor, but the origin of its specialization is poorly defined. Here we report on the role of the distinctive C-terminal extension present in Apg2 and other metazoan homologs. We found that the first part of this Apg2 subdomain, with propensity to adopt α-helical structure, interacts with the nucleotide binding domain of Hsc70 in a nucleotide-dependent manner, contributing significantly to the stability of the Hsc70:Apg2 complex. Moreover, the second intrinsically disordered segment of Apg2 C-terminal extension plays an important role as a downregulator of nucleotide exchange. An NMR analysis showed that the interaction with Hsc70 nucleotide binding domain modifies the chemical environment of residues located in important functional sites such as the interface between lobe I and II and the nucleotide binding site. Our data indicate that Apg2 C-terminal extension is a fine-tuner of human Hsc70 activity that optimizes the substrate remodeling ability of the chaperone system.
Assuntos
Proteínas de Choque Térmico HSC70 , Proteínas de Choque Térmico HSP110 , Humanos , Proteínas de Choque Térmico HSC70/química , Proteínas de Choque Térmico HSC70/metabolismo , Proteínas de Choque Térmico HSP110/química , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP40/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Chaperonas Moleculares/metabolismo , Nucleotídeos/metabolismo , Agregados Proteicos , Ligação ProteicaRESUMO
BACKGROUND: Pulmonary hypertension (PH) is a progressive and fatal cardiopulmonary disease characterized by pulmonary vascular remodeling and increased pulmonary vascular resistance and artery pressure. Vascular remodeling is associated with the excessive cell proliferation and migration of pulmonary artery smooth muscle cells (PASMCs). In this paper, the effects of heat shock protein-110 (HSP110) on PH were investigated. METHODS: The C57BL/6 mice and human PASMCs (HPASMCs) were respectively exposed to hypoxia to establish and simulate PH model in vivo and cell experiment in vitro. To HSP110 knockdown, the hypoxia mice and HPASMCs were infected with adeno-associated virus or adenovirus carring the shRNAs (short hairpin RNAs) for HSP110 (shHSP110). For HSP110 and yes-associated protein (YAP) overexpression, HPASMCs were infected with adenovirus vector carring the cDNA of HSP110 or YAP. The effects of HSP110 on PH development in mice and cell proliferation, migration and autophagy of PASMCs under hypoxia were assessed. Moreover, the regulatory mechanisms among HSP110, YAP and TEA domain transcription factor 4 (TEAD4) were investigated. RESULTS: We demonstrated that expression of HSP110 was significantly increased in the pulmonary arteries of mice and HPASMCs under hypoxia. Moreover, knockdown of HSP110 alleviated hypoxia-induced right ventricle systolic pressure, vascular wall thickening, right ventricular hypertrophy, autophagy and proliferation of PASMCs in mice. In addition, knockdown of HSP110 inhibited the increases of proliferation, migration and autophagy of HPASMCs that induced by hypoxia in vitro. Mechanistically, HSP110 knockdown inhibited YAP and transcriptional co-activator with PDZ-binding motif (TAZ) activity and TEAD4 nuclear expression under hypoxia. However, overexpression of HSP110 exhibited the opposite results in HPASMCs. Additionally, overexpression of YAP partially restored the effects of shHSP110 on HPASMCs. The interaction of HSP110 and YAP was verified. Moreover, TEAD4 could promote the transcriptional activity of HSP110 by binding to the HSP110 promoter under hypoxia. CONCLUSIONS: Our findings suggest that HSP110 might contribute to the development of PH by regulating the proliferation, migration and autophagy of PASMCs through YAP/TAZ-TEAD4 pathway, which may help to understand deeper the pathogenic mechanism in PH development.
Assuntos
Hipertensão Pulmonar , Animais , Movimento Celular/genética , Proliferação de Células/genética , Células Cultivadas , Proteínas de Ligação a DNA , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP110/farmacologia , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/prevenção & controle , Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Musculares/metabolismo , Miócitos de Músculo Liso/metabolismo , Artéria Pulmonar/metabolismo , Fatores de Transcrição de Domínio TEA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Remodelação VascularRESUMO
Heat shock protein 70 (Hsp70) is a molecular chaperone and central regulator of protein homeostasis (proteostasis). Paramount to this role is Hsp70's binding to client proteins and co-chaperones to produce distinct complexes, such that understanding the protein-protein interactions (PPIs) of Hsp70 is foundational to describing its function and dysfunction in disease. Mounting evidence suggests that these PPIs include both "canonical" interactions, which are universally conserved, and "non-canonical" (or "secondary") contacts that seem to have emerged in eukaryotes. These two categories of interactions involve discrete binding surfaces, such that some clients and co-chaperones engage Hsp70 with at least two points of contact. While the contributions of canonical interactions to chaperone function are becoming increasingly clear, it can be challenging to deconvolute the roles of secondary interactions. Here, we review what is known about non-canonical contacts and highlight examples where their contributions have been parsed, giving rise to a model in which Hsp70's secondary contacts are not simply sites of additional avidity but are necessary and sufficient to impart unique functions. From this perspective, we propose that further exploration of non-canonical contacts will generate important insights into the evolution of Hsp70 systems and inspire new approaches for developing small molecules that tune Hsp70-mediated proteostasis.
Assuntos
Eucariotos , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Chaperonas Moleculares/metabolismo , Ligação Proteica , Dobramento de ProteínaRESUMO
Decreased estrogen levels in menopause are associated with anthropometric, metabolic, and inflammatory impairments, predisposing women to cardiometabolic risk factors such as diabetes. Menopause and type two diabetes (DM2) are marked by altered heat shock response (HSR), shown by decreased expression of the 70-kDa heat shock protein in the intracellular milieu (iHSP70). While iHSP70 plays an anti-inflammatory role, extracellular HSP70 (eHSP70) may mediate pro-inflammatory pathways and has been associated with insulin resistance in DM2. Considering the roles of these proteins according to localization, the eHSP70-to-iHSP70 ratio (H-index) has been proposed as a biomarker for HSR. We, therefore, evaluated whether this biomarker is associated with glycemic and inflammatory status in postmenopausal women. In this transversal study, 36 postmenopausal women were grouped according to fasting glycemia status as either the control group (normoglycemic, ≤ 99 mg/dL) or DM2 (prediabetic and diabetic, glycemia ≥ 100 mg/dL). DM2 group showed higher triglyceride/glucose (TyG) index and plasma atherogenic index (PAI), both of which are indicators of cardiometabolic risk. In addition, we found that the eHSP70-to-iHSP70 ratio (plasma/peripheral blood mononuclear cells-PBMC ratio) was higher in the DM2 group, compared with the control group. Furthermore, blood leukocyte and glycemia levels were positively correlated with the eHSP70-to-iHSP70 ratio in women that presented H-index values above 1.0 (a.u.). Taken together, our results highlight the eHSP70-to-iHSP70 ratio as a biomarker of altered HSR in DM2 postmenopausal women.
Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Proteínas de Choque Térmico HSP70 , Pós-Menopausa , Estado Pré-Diabético , Biomarcadores/metabolismo , Glicemia , Doenças Cardiovasculares/diagnóstico , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Estrogênios , Feminino , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Leucócitos Mononucleares/metabolismo , Estado Pré-Diabético/complicações , Estado Pré-Diabético/metabolismo , TriglicerídeosRESUMO
Placenta accreta spectrum (PAS) accounts for 7% of maternal mortality and is associated with intraoperative and postoperative morbidity caused by massive blood loss, infection, and adjacent organ damage. The aims of this study were to identify the protein biomarkers of PAS and to further explore their pathogenetic roles in PAS. For this purpose, we collected five placentas from pregnant subjects with PAS complications and another five placentas from normal pregnancy (NP) cases. Then, we enriched protein samples by specifically isolating the trophoblast villous, deeply invading into the uterine muscle layer in the PAS patients. Next, fluorescence-based two-dimensional difference gel electrophoresis (2D-DIGE) and MALDI-TOF/MS were used to identify the proteins differentially abundant between PAS and NP placenta tissues. As a result, nineteen spots were determined as differentially abundant proteins, ten and nine of which were more abundant in PAS and NP placenta tissues, respectively. Then, specific validation with western blot assay and immunohisto/cytochemistry (IHC) assay confirmed that heat shock 70 kDa protein 4 (HSPA4) and chorionic somatomammotropin hormone (CSH) were PAS protein biomarkers. Further tube formation assays demonstrated that HSPA4 promoted the in vitro angiogenesis ability of vessel endothelial cells, which is consistent with the in vivo scenario of PAS complications. In this study, we not only identified PAS protein biomarkers but also connected the promoted angiogenesis with placenta invasion, investigating the pathogenetic mechanism of PAS.
Assuntos
Proteínas de Choque Térmico HSP110 , Placenta Acreta , Biomarcadores , Cesárea , Células Endoteliais/patologia , Feminino , Proteínas de Choque Térmico HSP110/metabolismo , Humanos , Placenta/patologia , Placenta Acreta/patologia , Placenta Acreta/cirurgia , GravidezRESUMO
BACKGROUND: Molecular chaperones assist protein folding, facilitate degradation of misfolded polypeptides, and thereby maintain protein homeostasis. Impaired chaperone activity leads to defective protein quality control that is implicated in multiple skeletal muscle diseases. The heat shock protein A4 (HSPA4) acts as a co-chaperone for HSP70. Previously, we showed that Hspa4 deletion causes impaired protein homeostasis in the heart. However, its functional role in skeletal muscle has not been explored. METHODS: We performed a comparative phenotypic and biochemical analyses of Hspa4 knockout (KO) mice with wild-type (WT) littermates. RESULTS: HSPA4 is markedly upregulated in regenerating WT muscle in vivo, and in differentiated myoblasts in vitro. Hspa4-KO mice are marked by growth retardation and increased variability in body weight, accompanied by 35% mortality rates during the peri-weaning period. The surviving Hspa4-KO mice experienced progressive skeletal muscle myopathy, characterized by increased number of muscle fibers with centralized nuclei, heterogeneous myofiber size distribution, inflammatory cell infiltrates and upregulation of embryonic and perinatal myosin heavy chain transcripts. Hspa4-KO muscles demonstrated an accumulation of autophagosome-associated proteins including microtubule associated protein1 light chain 3-II (LC3-II) and p62/sequestosome accompanied by increased number of TUNEL-positive nuclei. CONCLUSIONS: Our findings underscore the indispensable role of HSPA4 in maintenance of muscle integrity through contribution in skeletal muscle autophagy and apoptosis, which might provide a novel therapeutic strategy for skeletal muscle morbidities.
Assuntos
Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Choque Térmico , Doenças Musculares , Animais , Apoptose , Autofagia , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Chaperonas Moleculares/metabolismo , Músculo Esquelético/metabolismo , Doenças Musculares/genética , Doenças Musculares/metabolismoRESUMO
As a deacetylase, SIRT1 plays essential roles in various physiological events, from development to lifespan regulation. SIRT1 has been shown neuroprotective effects in neurodegeneration disorders such as Parkinson's disease (PD). However, the underlying molecular mechanisms are still not well understood. Here, we generated transgenic mice with increased expression of Sirt1 in the brain and examined the potential roles of SIRT1 in PD. Our data showed that SIRT1 repressed proinflammatory cytokine expression both in microglia and astrocytes. In MPTP induced PD model mice, lower levels of microglia and astrocyte activation were observed in SIRT1 transgenic mice. Moreover, the tyrosine hydroxylase (TH) loss in the substantia nigra pars compacta (SNpc) and striatum induced by MPTP was also attenuated by SIRT1. As a consequence, the behavioral defects induced by MPTP were largely prevented in SIRT1 transgenic mice. Mechanistically, SIRT1 interacts with heat shock 70 kDa protein 4 (HSPA4) and deacetylates it at 305, 351 and 605 lysine residues. This deacetylation modification induces the nuclear translocation of HSPA4 and thus to repress proinflammatory cytokine expression. On the contrary, mutated HSPA4, in which 305/351/605 lysine residues were replaced with arginine, was mainly localized in the cytoplasm and losses its repression on proinflammatory cytokine expression. Taken together, our data indicate that SIRT1 plays beneficial roles in PD model mice, which is likely due to, at least in part, its anti-inflammation activity in glial cells by deacetylating HSPA4. Furthermore, HSPA4 might be a druggable target for developing novel agents for treating neuroinflammation associated disorders such as PD.
Assuntos
Doença de Parkinson , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Acetilação , Animais , Citocinas , Modelos Animais de Doenças , Proteínas de Choque Térmico HSP110/metabolismo , Lisina , Camundongos , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Sirtuína 1/genéticaRESUMO
BACKGROUND/AIM: Heat shock protein 105 (HSP105) is overexpressed in various cancers, but not in normal tissues. We investigated the expression levels of HSP105 in cervical cancer and the efficacy of immunotherapy targeting HSP105. MATERIALS AND METHODS: Previously, we established human leukocyte antigen-A*02:01 (HLA-A2) restricted HSP105 peptide-specific cytotoxic T lymphocyte (CTL) clones from a colorectal cancer patient vaccinated with an HSP105 peptide. Herein, we evaluated the expression of HSP105 in cervical cancer and cervical intraepithelial neoplasia. Moreover, we tested the effectiveness of an HLA-A2-restricted HSP105 peptide-specific CTL clone against cervical cancer cell lines. RESULTS: HSP105 was expressed in 95% (19/20) of examined cervical cancer tissues. Moreover, the HSP105 peptide-specific CTL clone recognized HSP105- and HLA-A*02:01-positive cervical cancer cell lines and also showed that cytotoxicity against the cervical cancer cell lines depends on HSP105 peptide and HLA class I restricted manners. CONCLUSION: HSP105 could be an effective target for immunotherapy in patients with cervical cancer.
Assuntos
Proteínas de Choque Térmico HSP110/imunologia , Imunoterapia/métodos , Neoplasias do Colo do Útero/terapia , Animais , Linhagem Celular Tumoral , Feminino , Antígeno HLA-A2/imunologia , Antígeno HLA-A2/metabolismo , Proteínas de Choque Térmico HSP110/metabolismo , Humanos , Camundongos , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/transplante , Neoplasias do Colo do Útero/imunologia , Neoplasias do Colo do Útero/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The mammalian HSP105/110 family consists of four members, including Hsp105 and Apg-1, which function as molecular chaperones. Recently, we reported that Hsp105 knockdown increases sensitivity to the DNA-damaging agent Adriamycin but decreases sensitivity to the microtubule-targeting agent paclitaxel. However, whether the other Hsp105/110 family proteins have the same functional property is unknown. Here, we show that Apg-1 has different roles from Hsp105 in cell proliferation, cell division, and drug sensitivity. We generated the Apg-1-knockdown HeLa S3 cells by lentiviral expression of Apg-1-targeting short hairpin RNA. Knockdown of Apg-1 but not Hsp105 decreased cell proliferation. Apg-1 knockdown increased cell death upon Adriamycin treatment without affecting paclitaxel sensitivity. The cell synchronization experiment suggests that Apg-1 functions in mitotic progression at a different mitotic subphase from Hsp105, which cause difference in paclitaxel sensitivity. Since Apg-1 is overexpressed in certain types of tumors, Apg-1 may become a potential therapeutic target for cancer treatment without causing resistance to the microtubule-targeting agents.
Assuntos
Divisão Celular , Resistencia a Medicamentos Antineoplásicos , Proteínas de Choque Térmico HSP110/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Proteínas de Choque Térmico HSP110/genética , Células HeLa , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genéticaRESUMO
Heat shock proteins of 110 kDa (Hsp110s), a unique class of molecular chaperones, are essential for maintaining protein homeostasis. Hsp110s exhibit a strong chaperone activity preventing protein aggregation (the "holdase" activity) and also function as the major nucleotide-exchange factor (NEF) for Hsp70 chaperones. Hsp110s contain two functional domains: a nucleotide-binding domain (NBD) and substrate-binding domain (SBD). ATP binding is essential for Hsp110 function and results in close contacts between the NBD and SBD. However, the molecular mechanism of this ATP-induced allosteric coupling remains poorly defined. In this study, we carried out biochemical analysis on Msi3, the sole Hsp110 in Candida albicans, to dissect the unique allosteric coupling of Hsp110s using three mutations affecting the domain-domain interface. All the mutations abolished both the in vivo and in vitro functions of Msi3. While the ATP-bound state was disrupted in all mutants, only mutation of the NBD-SBDß interfaces showed significant ATPase activity, suggesting that the full-length Hsp110s have an ATPase that is mainly suppressed by NBD-SBDß contacts. Moreover, the high-affinity ATP-binding unexpectedly appears to require these NBD-SBD contacts. Remarkably, the "holdase" activity was largely intact for all mutants tested while NEF activity was mostly compromised, although both activities strictly depended on the ATP-bound state, indicating different requirements for these two activities. Stable peptide substrate binding to Msi3 led to dissociation of the NBD-SBD contacts and compromised interactions with Hsp70. Taken together, our data demonstrate that the exceptionally strong NBD-SBD contacts in Hsp110s dictate the unique allosteric coupling and biochemical activities.