Expression of Antioxidant Molecules and Heat Shock Protein 27 in Thyroid Tumors

Heat shock proteins in cancer - Known but always being rediscovered: Their perspectives in cancer immunotherapy

Heat shock proteins (HSPs) represent cellular chaperones that are classified into several families, including HSP27, HSP40, HSP60, HSP70, and HSP90. The role of HSPs in the cell includes the facilitation of protein folding and maintaining protein structure. Both processes play crucial roles during stress conditions in the cell such as heat shock, degradation, and hypoxia. Moreover, HSPs are important modulators of cellular proliferation and differentiation, and are strongly associated with the molecular orchestration of carcinogenesis. The expression and/or activity of HSPs in cancer cells is generally abnormally high and is associated with increased metastatic potential and activity of cancer stem cells, more pronounced angiogenesis, downregulated apoptosis, and the resistance to anticancer therapy in many patients. Based on the mentioned reasons, HSPs have strong potential as valid diagnostic, prognostic, and therapeutic biomarkers in clinical oncology. In addition, numerous papers describe the role of HSPs as chaperones in the regulation of immune responses inside and outside the cell. Importantly, highly expressed/activated HSPs may be inhibited via immunotherapeutic targets in various types of cancers. The aim of this work is to provide a comprehensive overview of the relationship between HSPs and the tumor cell with the intention of highlighting the potential use of HSPs in personalized cancer management.

Oxidative Stress Correlates with More Aggressive Features in Thyroid Cancer

Oxidative stress (OS) can have an impact in the pathogenesis and in the progression of thyroid cancer. We investigated the levels of reactive oxygen species (ROS) in 50 malignant and benign thyroid lesions and 41 normal tissues, and correlated them with the thyroid differentiation score-TDS and the clinico-pathologic features. NOX4 expression, GPx activity and the genetic pattern of tumors were evaluated. In malignant and benign lesions, ROS generation and NOX4 protein expression were higher than in normal tissues. Follicular (FTCs) and anaplastic/poorly differentiated cancers had increased OS relative to papillary tumors (PTCs). Moreover, OS in FTCs was higher than in follicular adenomas. Mutated PTCs showed increased OS compared with non-mutated PTCs. In malignant tumors, OS was inversely correlated with TDS, and directly correlated with tumor stage and ATA risk. GPx activity was increased in tumors compared with normal tissues, and inversely correlated to OS. In conclusion, our data indicate that thyroid tumors are exposed to higher OS compared with normal tissues, while showing a compensative increased GPx activity. OS correlates with tumor aggressiveness and mutations in the MEK-ERK pathway in PTC. The inverse correlation between OS and TDS suggests that ROS may repress genes involved in thyroid differentiation.

Selenium and Selenoproteins at the Intersection of Type 2 Diabetes and Thyroid Pathophysiology

Type 2 diabetes (T2D) is considered one of the largest global public-health concerns, affecting approximately more than 400 million individuals worldwide. The pathogenesis of T2D is very complex and, among the modifiable risk factors, selenium (Se) has recently emerged as a determinant of T2D pathogenesis and progression. Selenium is considered an essential element with antioxidant properties, and is incorporated into the selenoproteins involved in the antioxidant response. Furthermore, deiodinases, the enzymes responsible for homeostasis and for controlling the activity of thyroid hormones (THs), contain Se. Given the crucial action of oxidative stress in the onset of insulin resistance (IR) and T2D, and the close connection between THs and glucose metabolism, Se may be involved in these fundamental relationships; it may cover a dual role, both as a protective factor and as a risk factor of T2D, depending on its basal plasma concentration and the individual’s diet intake. In this review we discuss the current evidence (from experimental, observational and randomized clinical studies) on how Se is associated with the occurrence of T2D and its influence on the relationship between thyroid pathophysiology, IR and T2D.

Nestin Regulates Keap1-Nrf2-HO-1-Mediated Antioxidant Responses during Stress and Malignant Hematopoiesis

Objective

To investigate the role of nestin in regulating Keap1-nuclear factor erythroid-2-related factor 2 (Nrf2)-heme oxygenase-1-(HO-1-) mediated antioxidant responses in stress and malignant hematopoiesis.

Methods

The mRNA of peripheral blood mononuclear cells was extracted from 20 leukemia patients and 20 healthy people who were hospitalized in the Hematology Department of our hospital from September 2020 to December 2021, and the mRNA levels of nestin, Keap1, Nrf2, and HO-1 were detected by real-time- (RT-) PCR.

Results

Compared with healthy controls, the mRNA of nestin, Keap1, Nrf2, and HO-1 in peripheral blood mononuclear cells of leukemia patients was significantly upregulated.

Conclusion

The occurrence and development of leukemia are closely related to nestin regulating Keap1-Nrf2-Ho-1 signal pathway. Research Significance. This study determined the effect of nestin on the biological behavior of leukemia cells and its possible mechanism and confirmed that nestin may be a marker of tumor and tumor blood vessels.

Molecular Chaperones and Thyroid Cancer

Thyroid cancers are the most common of the endocrine system malignancies and progress must be made in the areas of differential diagnosis and treatment to improve patient management. Advances in the understanding of carcinogenic mechanisms have occurred in various fronts, including studies of the chaperone system (CS). Components of the CS are found to be quantitatively increased or decreased, and some correlations have been established between the quantitative changes and tumor type, prognosis, and response to treatment. These correlations provide the basis for identifying distinctive patterns useful in differential diagnosis and for planning experiments aiming at elucidating the role of the CS in tumorigenesis. Here, we discuss studies of the CS components in various thyroid cancers (TC). The chaperones belonging to the families of the small heat-shock proteins Hsp70 and Hsp90 and the chaperonin of Group I, Hsp60, have been quantified mostly by immunohistochemistry and Western blot in tumor and normal control tissues and in extracellular vesicles. Distinctive differences were revealed between the various thyroid tumor types. The most frequent finding was an increase in the chaperones, which can be attributed to the augmented need for chaperones the tumor cells have because of their accelerated metabolism, growth, and division rate. Thus, chaperones help the tumor cell rather than protect the patient, exemplifying chaperonopathies by mistake or collaborationism. This highlights the need for research on chaperonotherapy, namely the development of means to eliminate/inhibit pathogenic chaperones.

Molecular Chaperones in Osteosarcoma: Diagnosis and Therapeutic Issues

Osteosarcoma (OS) is the most common form of primary bone tumor affecting mainly children and young adults. Despite therapeutic progress, the 5-year survival rate is 70%, but it drops drastically to 30% for poor responders to therapies or for patients with metastases. Identifying new therapeutic targets is thus essential. Heat Shock Proteins (HSPs) are the main effectors of Heat Shock Response (HSR), the expression of which is induced by stressors. HSPs are a large family of proteins involved in the folding and maturation of other proteins in order to maintain proteostasis. HSP overexpression is observed in many cancers, including breast, prostate, colorectal, lung, and ovarian, as well as OS. In this article we reviewed the significant role played by HSPs in molecular mechanisms leading to OS development and progression. HSPs are directly involved in OS cell proliferation, apoptosis inhibition, migration, and drug resistance. We focused on HSP27, HSP60, HSP70 and HSP90 and summarized their potential clinical uses in OS as either biomarkers for diagnosis or therapeutic targets. Finally, based on different types of cancer, we consider the advantage of targeting heat shock factor 1 (HSF1), the major transcriptional regulator of HSPs in OS.

The Effect of Glutathione Peroxidase-1 Knockout on Anticancer Drug Sensitivities and Reactive Oxygen Species in Haploid HAP-1 Cells

The role of glutathione peroxidases (GPx) in cancer and their influence on tumor prognosis and the development of anticancer drug resistance has been extensively and controversially discussed. The aim of this study was to evaluate the influence of GPx1 expression on anticancer drug cytotoxicity. For this purpose, a GPx1 knockout of the near-haploid human cancer cell line HAP-1 was generated and compared to the native cell line with regards to morphology, growth and metabolic rates, and oxidative stress defenses. Furthermore, the IC₅₀ values of two peroxides and 16 widely used anticancer drugs were determined in both cell lines. Here we report that the knockout of GPx1 in HAP-1 cells has no significant effect on cell size, viability, growth and metabolic rates. Significant increases in the cytotoxic potency of hydrogen peroxide and tert-butylhydroperoxide, the anticancer drugs cisplatin and carboplatin as well as the alkylating agents lomustine and temozolomide were found. While a concentration dependent increases in intracellular reactive oxygen species (ROS) levels were observed for both HAP-1 cell lines treated with either cisplatin, lomustine or temozolamide, no significant enhancement in ROS levels was observed in the GPx1 knockout compared to the native cell line except at the highest concentration of temozolamide. On the other hand, a ca. 50% decrease in glutathione levels was noted in the GPx1 knockout relative to the native line, suggesting that factors other than ROS levels alone play a role in the increased cytotoxic activity of these drugs in the GPx1 knockout cells.

hMTH1 and GPX1 expression in human thyroid tissue is interrelated to prevent oxidative DNA damage

Oxidative stress (OS) is recognized as disturbance of cellular equilibrium between reactive oxygen species (ROS) formation and their elimination by antioxidant defense systems. One example of ROS-mediated damage is generation of potentially mutagenic DNA precursor, 8-oxodGTP. In human cells genomic 8-oxodGTP incorporation is prevented by the MutT homologue 1 (MTH1 or hMTH1 for human MTH1) protein. It is well established that malignant cells, including thyroid cancer cells, require hMTH1 for maintaining proliferation and cancerous transformation phenotype. Above observations led to the development of hMTH1 inhibitors as novel anticancer therapeutics. In the current study we present extensive analysis of oxidative stress responses determining sensitivity to hMTH1 deficiency in cultured thyroid cells. We observe here that hMTH1 depletion results in downregulation of several glutathione-dependent OS defense system factors, including GPX1 and GCLM, making some of the tested thyroid cell lines highly dependent on glutathione levels. This is evidenced by the increased ROS burden and enhanced proliferation defect after combination of hMTH1 siRNA and glutathione synthesis inhibition. Moreover, due to the lack of data on hMTH1 expression in human thyroid tumor specimens we decided to perform detailed analysis of hMTH1 expression in thyroid tumor and peri-tumoral tissues from human patients. Our results allow us to propose here that anticancer activity of hMTH1 suppression may be boosted by combination with agents modulating glutathione pool, but further studies are necessary to precisely identify backgrounds susceptible to such combination treatment.

Small Heat Shock Proteins in Cancers: Functions and Therapeutic Potential for Cancer Therapy

Small heat shock proteins (sHSPs) are ubiquitous ATP-independent chaperones that play essential roles in response to cellular stresses and protein homeostasis. Investigations of sHSPs reveal that sHSPs are ubiquitously expressed in numerous types of tumors, and their expression is closely associated with cancer progression. sHSPs have been suggested to control a diverse range of cancer functions, including tumorigenesis, cell growth, apoptosis, metastasis, and chemoresistance, as well as regulation of cancer stem cell properties. Recent advances in the field indicate that some sHSPs have been validated as a powerful target in cancer therapy. In this review, we present and highlight current understanding, recent progress, and future challenges of sHSPs in cancer development and therapy.

Extracellular Chaperones as Novel Biomarkers of Overall Cancer Progression and Efficacy of Anticancer Therapy

Exosomal heat shock proteins (Hsps) are involved in intercellular communication both in physiological and pathological conditions. They play a role in key processes of carcinogenesis including immune system regulation, cell differentiation, vascular homeostasis and metastasis formation. Thus, exosomal Hsps are emerging biomarkers of malignancies and possible therapeutic targets. Adolescents and young adults (AYAs) are patients aged 15–39 years. This age group, placed between pediatric and adult oncology, pose a particular challenge for cancer management. New biomarkers of cancer growth and progression as well as prognostic factors are desperately needed in AYAs. In this review, we attempted to summarize the current knowledge on the role of exosomal Hsps in selected solid tumors characteristic for the AYA population and/or associated with poor prognosis in this age group. These included malignant melanoma, brain tumors, and breast, colorectal, thyroid, hepatocellular, lung and gynecological tract carcinomas. The studies on exosomal Hsps in these tumors are limited; however; some have provided promising results. Although further research is needed, there is potential for future clinical applications of exosomal Hsps in AYA cancers, both as novel biomarkers of disease presence, progression or relapse, or as therapeutic targets or tools for drug delivery.

Heat shock proteins in thyroid malignancies: Potential therapeutic targets for poorly-differentiated and anaplastic tumours?

Thyroid cancer is the most common endocrine malignancy, with well-differentiated subtypes characterized by an excellent prognosis due to their optimal sensitivity to standard therapies whereas poorly differentiated and anaplastic tumours by chemo/radio-resistance and unfavourable outcome. Heat Shock Proteins (HSPs) are molecular chaperones overexpressed in thyroid malignancies and involved in crucial functions responsible for thyroid carcinogenesis, as protection from apoptosis, drug resistance and cell migration. Thus, HSPs inhibitors have been proposed as novel therapeutic agents in thyroid cancer to revert molecular mechanisms of tumour progression. In this review, we report an overview on the biological role of HSPs, and specifically HSP90s, in thyroid cancer and their potential involvement as biomarkers. We discuss the rationale to evaluate HSPs inhibitors as innovative anticancer agents in specific subtypes of thyroid cancer characterized by poor response to therapies with the objective to target single family chaperones to reduce, simultaneously, the expression/stability of multiple client proteins.

Effects of Prolonged Dietary Curcumin Exposure on Skeletal Muscle Biochemical and Functional Responses of Aged Male Rats

Oxidative stress resulting from decreased antioxidant protection and increased reactive oxygen and nitrogen species (RONS) production may contribute to muscle mass loss and dysfunction during aging. Curcumin is a phenolic compound shown to upregulate antioxidant defenses and directly quench RONS in vivo. This study determined the impact of prolonged dietary curcumin exposure on muscle mass and function of aged rats. Thirty-two-month-old male F344xBN rats were provided a diet with or without 0.2% curcumin for 4 months. The groups included: ad libitum control (CON; n = 18); 0.2% curcumin (CUR; n = 18); and pair-fed (PAIR; n = 18) rats. CUR rats showed lower food intake compared to CON, making PAIR a suitable comparison group. CUR rats displayed larger plantaris mass and force production (vs. PAIR). Nuclear fraction levels of nuclear factor erythroid-2 related-factor-2 were greater, and oxidative macromolecule damage was lower in CUR (vs. PAIR). There were no significant differences in measures of antioxidant status between any of the groups. No difference in any measure was observed between CUR and CON rats. Thus, consumption of curcumin coupled with reduced food intake imparted beneficial effects on aged skeletal muscle. The benefit of curcumin on aging skeletal muscle should be explored further.

The regulatory effect of saffron stigma on the gene expression of the glucose metabolism key enzymes and stress proteins in streptozotocin-induced diabetic rats

Oxidative stress plays a crucial role in the pathogenesis of hyperglycemia mediated complications. Since a great number of researches have reported antioxidant features of saffron, this study investigated the antioxidant effect of saffron stigma extract (SSE) in streptozotocin-induced diabetic rats. Twenty eight diabetic male Wistar rats were divided in four groups containing: two diabetic groups receiving 25 and 100 mg/kg SSE respectively, one diabetic group receiving glibenclamide (0.6 mg/kg) and one diabetic control group receiving normal saline. Seven healthy adult male Wistar rats were also used as normal control group. After treatment (21 days), fasting blood glucose, insulin, oxidative stress markers, and pancreatic regeneration were assessed. The gene expression level of heat shock factor1, heat shock protein 27, and heat shock protein 70, also glucokinase (GK), and glucose 6-phosphatase (G6Pase) were determined using real-time polymerase chain reaction (RT-PCR). SSE in high dose (100 mg/kg) reduced fasting blood glucose (8.3 ± 0.4 mmol/L) compared with diabetic control (24.6 ± 1.2 mmol/L) (P < 0.05). Furthermore, SSE in high dose increased insulin level compared with diabetic control group (12.7 ± 0.6 vs 7.1 ± 0.3 μU/mL). RT-PCR analysis revealed decline in mRNA levels of stress proteins and G6Pase and increase in mRNA level of GK in treatment diabetic groups compared with diabetic control group. Data showed antioxidant and antidiabetic effects of SSE through altering insulin release and glucose metabolism pathways. Hypoglycemic potential of SSE may be due to change in GK and G6Pase enzymes expression. These findings provide a basis for the therapeutic potential of saffron in treatment of diabetes.

Effect of liposome‑mediated HSP27 transfection on collagen synthesis in alveolar type II epithelial cells

To investigate the effect of liposome Lipofectamine® 2000‑mediated HSP27 plasmid transfection in A549 human alveolar type II epithelial cell line on collagen synthesis during transforming growth factor‑β1 (TGF‑β1)‑induced type II epithelial cell transition to myofibroblasts. Cells were transfected with varying ratios of the Lipofectamine® 2000‑mediated heat shock protein 27 (HSP27) plasmid and the transfection efficiency was determined using flow cytometry. The maximum transfection efficacy was confirmed by laser confocal microscopy. HSP gene expression and the most efficient HSP27 plasmid were determined using reverse transcription‑quantitative polymerase chain reaction. Western blot analysis was used to examine HSP27 and collagen expression levels. With a transfection efficiency of 83%, the 8 µg:20 µl ratio of liposome: Plasmid had the highest transfection levels. Among the four different interference sequences in the HSP27 plasmid, the D sequence had the highest interference effect with 70% silencing of the HSP27 gene. The expression of type I and III collagen in TGF‑β1‑induced transition of A549 human alveolar type II epithelial cell line to myofibroblasts was significantly downregulated by the successful transfection with HSP27‑interfering plasmid. The expression of type I and III collagen in the TGF‑β1‑induced transition of A549 cells to myofibroblasts was significantly downregulated by transfection of A549 cells with HSP27 plasmid D‑interfering sequence and optimal ratio of Lipofectamine® 2000 and HSP27 plasmid.

Targeting Heat Shock Proteins in Cancer: A Promising Therapeutic Approach

Heat shock proteins (HSPs) are a large family of chaperones that are involved in protein folding and maturation of a variety of "client" proteins protecting them from degradation, oxidative stress, hypoxia, and thermal stress. Hence, they are significant regulators of cellular proliferation, differentiation and strongly implicated in the molecular orchestration of cancer development and progression as many of their clients are well established oncoproteins in multiple tumor types. Interestingly, tumor cells are more HSP chaperonage-dependent than normal cells for proliferation and survival because the oncoproteins in cancer cells are often misfolded and require augmented chaperonage activity for correction. This led to the development of several inhibitors of HSP90 and other HSPs that have shown promise both preclinically and clinically in the treatment of cancer. In this article, we comprehensively review the roles of some of the important HSPs in cancer, and how targeting them could be efficacious, especially when traditional cancer therapies fail.

Heat Shock Proteins and Cancer

Heat shock proteins (HSPs) constitute a large family of proteins involved in protein folding and maturation whose expression is induced by heat shock or other stressors. The major groups are classified based on their molecular weights and include HSP27, HSP40, HSP60, HSP70, HSP90, and large HSPs. HSPs play a significant role in cellular proliferation, differentiation, and carcinogenesis. In this article we comprehensively review the roles of major HSPs in cancer biology and pharmacology. HSPs are thought to play significant roles in the molecular mechanisms leading to cancer development and metastasis. HSPs may also have potential clinical uses as biomarkers for cancer diagnosis, for assessing disease progression, or as therapeutic targets for cancer therapy.