Nuclear heat shock protein 110 expression is associated with poor prognosis and hyperthermo-chemotherapy resistance in gastric cancer patients with peritoneal metastasis

Exploration of small-molecule inhibitors targeting Hsp110 as novel therapeutics

The heat shock protein (HSP) 110 family has a key role as a unique class of molecular chaperones maintaining cellular proteostasis in eukaryotes. Abnormal activation of Hsp110 has been implicated in several diseases. Given its important role in pathogenesis, Hsp110 has become a novel drug target for disease diagnosis and targeted therapy. Thus, targeting Hsp110 or its interactions with client proteins offers new therapeutic approaches. Recent studies of small-molecule inhibitors that target Hsp110 in vitro and in vivo have yielded encouraging results. In this review, we provide an overview of novel therapeutics targeting Hsp110, mainly inhibitors of protein-protein interactions (PPIs), together with a brief discussion of the relevant challenges, opportunities, and future directions.

Heat shock protein 110: A novel candidate for disease diagnosis and targeted therapy

The heat shock protein 110 (Hsp110) family in eukaryotes plays a pivotal role in maintaining cellular proteostasis. As a unique class of molecular chaperones, Hsp110s act as both independent chaperones and cochaperones for other essential molecular chaperones. Malfunction of Hsp110s is involved in many diseases. Thus targeting Hsp110s or its interactions with client proteins may provide new approaches for developing therapeutics. In this review, we describe the current understanding of the role and molecular mechanism of Hsp110s in disease development, and discuss the recent exploration of Hsp110s as potential targets to provide a novel direction for disease diagnosis and targeted therapy.

Inhibition of breast cancer growth with AN-329, a novel Hsp110 inhibitor, by inactivating p-STAT3/c-Myc axis

Breast cancer, a leading cause of cancer-related mortality in women, is characterized by its propensity for metastasis. Heat shock protein 110 (Hsp110), a molecular chaperone encoded by the HSPH1 gene, has been implicated in cancer progression, including breast cancer, where it is upregulated and associated with worse outcomes. However, the role of Hsp110 in breast cancer pathogenesis and its potential as a therapeutic target have not been thoroughly investigated. This study utilized the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) database to analyze HSPH1 gene expression in breast cancer and its correlation with tumor progression and survival. Furthermore, a comprehensive screen of the Specs database led to the identification of AN-329, a novel inhibitor that binds directly to the nucleotide-binding domain of Hsp110, neutralizing its chaperone activity and inhibiting breast cancer cell growth. AN-329 was validated in vitro for its antitumor efficacy and was found to regulate the cell cycle through the p-STAT3/c-Myc axis. This work suggests that AN-329 could be a promising lead for developing innovative therapeutic agents against breast cancer, warranting further research and potential clinical translation.

Knockdown of HSP110 attenuates hypoxia-induced pulmonary hypertension in mice through suppression of YAP/TAZ-TEAD4 pathway

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.

The Role of Hyperthermia in the Treatment of Peritoneal Surface Malignancies

PURPOSE OF REVIEW

Hyperthermia is used to treat peritoneal surface malignancies (PSM), particularly during hyperthermic intraperitoneal chemotherapy (HIPEC). This manuscript provides a focused update of hyperthermia in the treatment of PSM.

RECENT FINDINGS

The heterogeneous response to hyperthermia in PSM can be explained by tumor and treatment conditions. PSM tumors may resist hyperthermia via metabolic and immunologic adaptation. The thermodynamics of HIPEC are complex and require computational fluid dynamics (CFD). The clinical evidence supporting the benefit of hyperthermia is largely observational. Continued research will allow clinicians to characterize and predict the individual response of PSM to hyperthermia. The application of hyperthermia in current HIPEC protocols is mostly empirical. Thus, modeling heat transfer with CFD is a necessary task if we are to achieve consistent and reproducible hyperthermia. Although observational evidence suggests a survival benefit of hyperthermia, no clinical trial has tested the individual role of hyperthermia in PSM.

HSP70 promotes tumor progression by stabilizing Skp2 expression in gastric cancer cells

Gastric cancer (GC) has one of the highest tumor incidences worldwide. Heat shock protein 70 (HSP70) is highly expressed and plays a critical role in the occurrence, progression, metastasis, poor prognosis, and drug resistance of GC. However, the underlying mechanisms of HSP70 are not clear. To explore the regulatory role of HSP70 in GC, we performed cell counting kit-8 (CCK-8) and EdU staining assays to assess cell proliferation; immunohistochemistry and western blot analyses to assess protein expression; coimmunoprecipitation (Co-IP) assays to assess interactions between two proteins; and immunofluorescence to assess protein expression and localization. HSP70 was highly expressed in clinical samples from patients with GC and indicated a poor prognosis. HSP70 inhibition enhanced the sensitivity of GC cells to thermochemotherapy. Furthermore, we found that S phase kinase-associated protein 2 (Skp2) was highly expressed in GC and correlated with HSP70 in array data from The Cancer Genome Atlas (TCGA). Importantly, HSP70 inhibition promoted Skp2 degradation. Skp2 overexpression abrogated HSP70 inhibition-induced cell cycle arrest, suggesting that the role of HSP70 in GC depends on Skp2 expression. Our results illustrate a possible regulatory mechanism of HSP70 and may provide a therapeutic strategy for overcoming resistance to thermochemotherapy.

The Prognostic Significance of Hsp70 in Patients with Colorectal Cancer Patients: A PRISMA-Compliant Meta-Analysis

Background

Hsp70 (heat shock protein 70) plays a key role in carcinogenesis and cancer progression. However, the relationship between the Hsp70 expression level and the colorectal cancer patient survival is unknown. This study is aimed at investigating the relationship between Hsp70 and the prognosis of colorectal carcinoma patients.

Methods

PubMed, Web of Science, and Embase were used for systematic computer literature retrieval. Stata SE14.0 software was used for quantitative meta-analysis. Besides, data was extracted from selected articles. Relationships between Hsp70 expression level and prognosis were further studied. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were also computed.

Results

A total of 11 potentially eligible studies with 2269 patients were identified in 10 tumors from PubMed, Web of Science, and Embase. Hsp70 overexpression was associated with poor overall survival (OS) and disease-free survival (DFS) in colorectal carcinoma patients (HRs, 0.65 (95% CI: 0.52-0.78) and 0.77 (95% CI: 0.23-1.32), respectively).

Conclusions

Hsp70 overexpression can predict poor survival in colorectal cancer patients.

Nanofitins targeting heat shock protein 110: An innovative immunotherapeutic modality in cancer

The presence of an inactivating heat shock protein 110 (HSP110) mutation in colorectal cancers has been correlated with an excellent prognosis and with the ability of HSP110 to favor the formation of tolerogenic (M2-like) macrophages. These clinical and experimental results suggest a potentially powerful new strategy against colorectal cancer: the inhibition of HSP110. In this work, as an alternative to neutralizing antibodies, Nanofitins (scaffold ~7 kDa proteins) targeting HSP110 were isolated from the screening of a synthetic Nanofitin library, and their capacity to bind (immunoprecipitation, biolayer interferometry) and to inhibit HSP110 was analyzed in vitro and in vivo. Three Nanofitins were found to inhibit HSP110 chaperone activity. Interestingly, they share a high degree of homology in their variable domain and target the peptide-binding domain of HSP110. In vitro, they inhibited the ability of HSP110 to favor M2-like macrophages. The Nanofitin with the highest affinity, A-C2, was studied in the CT26 colorectal cancer mice model. Our PET/scan experiments demonstrate that A-C2 may be localized within the tumor area, in accordance with the reported HSP110 abundance in the tumor microenvironment. A-C2 treatment reduced tumor growth and was associated with an increase in immune cells infiltrating the tumor and particularly cytotoxic macrophages. These results were confirmed in a chicken chorioallantoic membrane tumor model. Finally, we showed the complementarity between A-C2 and an anti-PD-L1 strategy in the in vivo and in ovo tumor models. Overall, Nanofitins appear to be promising new immunotherapeutic lead compounds.

KNK437 restricts the growth and metastasis of colorectal cancer via targeting DNAJA1/CDC45 axis

As an inhibitor of heat shock proteins (HSPs), KNK437 has been reported to play an anti-tumor role in several cancers. But its therapeutic effect and mechanisms in colorectal cancer (CRC) remain unclear. Here, KNK437 sharply inhibited the level of DnaJ heat shock protein family (Hsp40) member A1 (DNAJA1), followed by DNAJB1, but had little effect on the levels of HSP27, HSP105, HSP90, and HSP70 in CRC cells. DNAJA1 promoted CRC cell proliferation in vitro and tumor growth and metastasis in vivo. Mechanistically, DNAJA1 was activated by E2F transcription factor 1 (E2F1) and then promoted cell cycle by stabilizing cell division cycle protein 45 (CDC45), which could be reversed by KNK437. DNAJA1 was significantly upregulated in CRC tissues and positively correlated with serosa invasion, lymph node metastasis. High level of DNAJA1 predicted poor prognosis for CRC patients. Its expression was highly linked with E2F1 and CDC45 in CRC tissues. More importantly, KNK437 significantly suppressed the growth of DNAJA1 expressing tumor in vivo. The combined treatment of KNK437 with 5-FU/L-OHP chemotherapy reduced liver metastasis of CRC. These data reveal a novel mechanism of KNK437 in anti-tumor therapy of CRC and provides a newly therapeutic strategy with potential translation to the CRC patients.

Heat Shock Proteins and Ovarian Cancer: Important Roles and Therapeutic Opportunities

Ovarian cancer is a serious cause of death in gynecological oncology. Delayed diagnosis and poor survival rates associated with late stages of the disease are major obstacles against treatment efforts. Heat shock proteins (HSPs) are stress responsive molecules known to be crucial in many cancer types including ovarian cancer. Clusterin (CLU), a unique chaperone protein with analogous oncogenic criteria to HSPs, has also been proven to confer resistance to anti-cancer drugs. Indeed, these chaperone molecules have been implicated in diagnosis, prognosis, metastasis and aggressiveness of various cancers. However, relative to other cancers, there is limited body of knowledge about the molecular roles of these chaperones in ovarian cancer. In the current review, we shed light on the diverse roles of HSPs as well as related chaperone proteins like CLU in the pathogenesis of ovarian cancer and elucidate their potential as effective drug targets.

Selecting the first chemical molecule inhibitor of HSP110 for colorectal cancer therapy

Pro-survival stress-inducible chaperone HSP110 is the only HSP for which a mutation has been found in a cancer. Multicenter clinical studies demonstrated a direct association between HSP110 inactivating mutation presence and excellent prognosis in colorectal cancer patients. Here, we have combined crystallographic studies on human HSP110 and in silico modeling to identify HSP110 inhibitors that could be used in colorectal cancer therapy. Two molecules (foldamers 33 and 52), binding to the same cleft of HSP110 nucleotide-binding domain, were selected from a chemical library (by co-immunoprecipitation, AlphaScreening, Interference-Biolayer, Duo-link). These molecules block HSP110 chaperone anti-aggregation activity and HSP110 association to its client protein STAT3, thereby inhibiting STAT3 phosphorylation and colorectal cancer cell growth. These effects were strongly decreased in HSP110 knockdown cells. Foldamer's 33 ability to inhibit tumor growth was confirmed in two colorectal cancer animal models. Although tumor cell death (apoptosis) was noted after treatment of the animals with foldamer 33, no apparent toxicity was observed, notably in epithelial cells from intestinal crypts. Taken together, we identified the first HSP110 inhibitor, a possible drug-candidate for colorectal cancer patients whose unfavorable outcome is associated to HSP110.