Treatment of tumors with vitamin E suppresses myeloid derived suppressor cells and enhances CD8+ T cell-mediated antitumor effects

Delineating the Immunotherapeutic Potential of Vitamin E and Its Analogues in Cancer: A Comprehensive Narrative Review

Cancer is a disease resulting from uncontrolled cell division, which significantly contributes to human mortality rates. An alternative approach to cancer treatment, such as cancer immunotherapy, is needed as the existing chemotherapy and radiotherapy approaches target the cancer cells and healthy dividing cells. Vitamin E is a plant-derived lipid-soluble antioxidant with numerous health-promoting benefits, including anticancer and immunomodulatory properties. Vitamin E comprises eight natural isoforms: tocopherols (α, β, δ, and γ) and tocotrienols (α, β, δ, and γ). While initial research focused on the anticancer properties of α-tocopherol, there is growing interest in other natural forms and modified synthetic analogues of vitamin E due to their unique properties and enhanced anticancer effects. Hence, this review is aimed at outlining the effect of vitamin E and its analogues at various steps of the cancer-immunity cycle that can be used to stimulate anticancer immune responses.

Isolation, characterization and pharmacological potentials of methanol extract of Cassia fistula leaves: Evidenced from mice model along with molecular docking analysis

The purpose of the current investigation was to conduct a detailed analysis of the chemical components and medicinal properties of the methanolic crude extract derived from the leaves of Cassia fistula. This analysis was carried out using both experimental (in vivo) and computational (in silico) methods. Eleven chemicals were chromatographically isolated using GC-MS/MS, which utilizes a library of NIST and Wiley 2020 versions. FTIR analysis of the extract was performed to identify the functional group of the compounds. The glucose-lowering capacity, analgesic, and anti-diarrheal activities of methanolic crude extract were analyzed utilizing a well-known oral glucose tolerance test, tail immersion method, writhing assay, and castor oil-induced diarrheal mice methods, respectively. After 60 min, 120 min, and 180 min of loading the drugs, a significant reduction of blood glucose levels was examined (p < 0.05) in all the extracts of this plant (200 mg/kg, 400 mg/kg and 600 mg/kg) utilized in this research at a time-dependent manner. Similarly, all the crude extracts showed significant (p < 0.05) effects against pain centrally and peripherally compared to the standard drug morphine (2 mg/kg bw) and diclofenac sodium (50 mg/kg bw). Moreover, the methanol extract (400 mg/kg bw) manifested anti-diarrheal efficacy by inhibiting 72.0 % of the diarrheal episode in mice compared to the standard drug loperamide (inhibition = 80.0%). The results of the computational investigations corroborated existing in-vivo findings. Greater or close to equivalent binding affinity to the active binding sites of kappa opioid receptor, glucose transporter 3 (GLUT 3), and cyclooxygenase 2 was indicative of the potential anti-diarrheal, hypoglycemic, and analgesic characteristics of the isolated compounds (COX-2). Moreover, anticancer and antimicrobial potentiality was also found impressive through evaluation of binding affinity with epidermal growth factor receptor (EGFR) and dihydrofolate reductase (DHFR) receptors. Results from this study indicated that C. fistula might be a beneficial natural resource for treating diarrhea, hyperglycemia, and pain. However, additional research is required to conduct a comprehensive phytochemical screening and establish precise action mechanisms of the crude extract or the plant-derived compounds.

Antioxidant and Anti-Tumor Effects of Dietary Vitamins A, C, and E

Oxidative stress, a condition characterized by an imbalance between pro-oxidant molecules and antioxidant defense systems, is increasingly recognized as a key contributor to cancer development. This is because the reactive oxygen species (ROS) generated during oxidative stress can damage DNA, proteins, and lipids to facilitate mutations and other cellular changes that promote cancer growth. Antioxidant supplementation is a potential strategy for decreasing cancer incidence; by reducing oxidative stress, DNA damage and other deleterious cellular changes may be attenuated. Several clinical trials have been conducted to investigate the role of antioxidant supplements in cancer prevention. Some studies have found that antioxidant supplements, such as vitamin A, vitamin C, and vitamin E, can reduce the risk of certain types of cancer. On the other hand, some studies posit an increased risk of cancer with antioxidant supplement use. In this review, we will provide an overview of the current understanding of the role of oxidative stress in cancer formation, as well as the potential benefits of antioxidant supplementation in cancer prevention. Additionally, we will discuss both preclinical and clinical studies highlighting the potentials and limitations of preventive antioxidant strategies.

Fat-Soluble Vitamin Deficiencies and Disruption of the Immune System in Pancreatic Cancer: A Vicious Cycle

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is currently an increasing contributor to cancer-related mortality. Despite advances in cancer treatment, PDAC survival rates have remained roughly unchanged over the years. Specifically, late diagnosis and insensitivity to currently available therapeutic regimens have been identified as the main causes for its poor survival. Pancreatic exocrine insufficiency (PEI) is a typical complication associated with PDAC diagnosis and pancreatic surgery. Pancreatic exocrine insufficiency, a major contributor to maldigestion in PDAC, is often not treated because it remains undetected because of lack of overt signs and symptoms. In this review, we will focus on the major consequences of PEI, including the inadequacy of lipase excretion, which results in deficiency of fat-soluble vitamins. Because PDAC is known for its immune-high jacking mechanisms, we describe key features in which deficiencies of fat-soluble vitamins may contribute to the aggressive biological behavior and immune evasion in PDAC. Because PEI has been shown to worsen survival rates in patients with PDAC, detecting PEI and the related fat-soluble vitamin deficits at the time of PDAC diagnosis is critical. Moreover, timely supplementation of pancreatic enzymes and fat-soluble vitamins may improve outcomes for PDAC patients.

Natural Products and their Derivatives as Immune Check Point Inhibitors: Targeting Cytokine/Chemokine Signalling in Cancer

Cancer immunotherapy is the new generation and widely accepted form of tumour treatment. It is, however, associated with exclusive challenges which include organ-specific inflammation, and single-target strategies. Therefore, approaches that can enhance the efficiency of existing immunotherapies and expand their indications are required for the further development of immunotherapy. Natural products and medicines are stated to have this desired effect on cancer immunotherapy (adoptive immune-cells therapy, cancer vaccines, and immune-check point inhibitors). They refurbish the immunosuppressed tumour microenvironment, which is the primary location of interaction of tumour cells with the host immune system. Various immune cell subsets, via interaction with cytokine/chemokine receptors, are recruited into this microenvironment, and these subsets have roles in tumour progression and treatment responsiveness. This review summarises cytokine/chemokine signalling, types of cancer immunotherapy and the herbal medicine-derived natural products targeting cytokine/chemokines and immune checkpoints. These natural compounds possess immunomodulatory activities and exert their anti-tumour effect by either blocking the interaction or modulating the expression of the proteins linked with immune checkpoint signaling pathways. Some compounds also show a synergistic effect in combination with existing monoclonal antibody drugs to reverse the tumour microenvironment. Additionally, we have also reported some studies about the derivatives and formulations used to overcome the limitations of natural forms. This review can provide important insights for directing future research.

Multi-faced roles of reactive oxygen species in anti-tumor T cell immune responses and combination immunotherapy

T cells play a central role in anti-tumor immunity, and reactive oxygen species (ROS) lie at the crossroad on the anti-tumor T cell responses. To activate efficient T cell immunity, a moderate level of ROS is needed, however, excessive ROS would cause toxicity to the T cells, because the improper level leads to the formation and maintenance of an immunosuppressive tumor microenvironment. Up to date, strategies that modulate ROS, either increasing or decreasing, have been widely investigated. Some of them are utilized in anti-tumor therapies, showing inevitable impacts on the anti-tumor T cell immunity with both obverse and reverse sides. Herein, the impacts of ROS-increasing and ROS-decreasing treatments on the T cell responses in the tumor microenvironment are reviewed and discussed. At the same time, outcomes of combination immunotherapies are introduced to put forward inspirations to unleash the potential of immunotherapies.

Landscape of Myeloid-derived Suppressor Cell in Tumor Immunotherapy

Myeloid-derived suppressor cells (MDSC) are a group of immature cells that produced by emergency myelopoiesis. Emerging evidences have identified the vital role of MDSC in cancer microenvironment, in which MDSC exerts both immunological and non-immunological activities to assist the progression of cancer. Advances in pre-clinical research have provided us the understanding of MDSC in cancer context from the perspective of molecular mechanism. In clinical scenario, MDSC and its subsets have been discovered to exist in peripheral blood and tumor site of patients from various types of cancers. In this review, we highlight the clinical value of MDSC in predicting prognosis of cancer patients and the responses of immunotherapies, therefore to propose the MDSC-inhibiting strategy in the scenario of cancer immunotherapies. Phenotypes and biological functions of MDSC in cancer microenvironment are comprehensively summarized to provide potential targets of MDSC-inhibiting strategy from the aspect of molecular mechanisms.

Improvement of hepatitis B vaccine to induce IFN-γ cytokine response: A new formulation

Hepatitis B virus (HBV) infection is limited through vaccination against HBsAg formulated in the Alum adjuvant. However, this alum-formulated vaccine fails to be preventive in some cases, also known as non-responders. Recent studies have shown the immunomodulatory effect of α-tocopherol in various models. Here, we developed a new formulation for HBsAg using α-tocopherol, followed by assessment of immune responses. Experimental BALB/c mice were immunized with a commercial alum-based vaccine or the one formulated in α-tocopherol at different doses. Mice were immunized subcutaneously with 5 μg of HBsAg with different formulations three times with 2-week intervals. Specific total IgG, IgG1, and IgG2a isotypes of antibodies were measured by ELISA. Immunologic cytokines, such as IFN-γ, IL-4, IL-2, and TNF-α, were also evaluated through commercial ELISA kits. Our results showed that the new α-tocopherol-formulated vaccine had the ability to reinforce specific total IgG responses. Moreover, α-tocopherol in the HBsAg vaccine increased IFN-γ, IL-2, and TNF-α cytokines at higher concentrations; however, the vaccine suppressed IL-4 cytokine release. At a lower concentration of α-tocopherol, the IL-4 cytokine response increased without a positive effect on IFN-γ and TNF-α cytokine response. It seems that α-tocopherol can change the immune responses against HBsAg; however, the type of response depends on the dose of α-tocopherol used in the vaccine formulation.

Metabolic reprogramming of myeloid-derived suppressor cells: An innovative approach confronting challenges

Immune cells such as T cells, macrophages, dendritic cells, and other immunoregulatory cells undergo metabolic reprogramming in cancer and inflammation-derived microenvironment to meet specific physiologic and functional demands. Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells that are characterized by immunosuppressive activity, which plays a key role in host immune homeostasis. In this review, we have discussed the core metabolic pathways, including glycolysis, lipid and fatty acid biosynthesis, and amino acid metabolism in the MDSCs under various pathologic situations. Metabolic reprogramming is a determinant of the phenotype and functions of MDSCs, and is therefore a novel therapeutic possibility in various diseases.

Targeting the tumor immune microenvironment with "nutraceuticals": From bench to clinical trials

The occurrence of immune effector cells in the tissue microenvironment during neoplastic progression is critical in determining tumor growth outcomes. On the other hand, tumors may also avoid immune system-mediated elimination by recruiting immunosuppressive leukocytes and soluble factors, which coordinate a tumor microenvironment that counteracts the efficiency of the antitumor immune response. Checkpoint inhibitor therapy results have indicated a way forward via activation of the immune system against cancer. Widespread evidence has shown that different compounds in foods, when administered as purified substances, can act as immunomodulators in humans and animals. Although there is no universally accepted definition of nutraceuticals, the term identifies a wide category of natural compounds that may impact health and disease statuses and includes purified substances from natural sources, plant extracts, dietary supplements, vitamins, phytonutrients, and various products with combinations of functional ingredients. In this review, we summarize the current knowledge on the immunomodulatory effects of nutraceuticals with a special focus on the cancer microenvironment, highlighting the conceptual benefits or drawbacks and subtle cell-specific effects of nutraceuticals for envisioning future therapies employing nutraceuticals as chemoadjuvants.

Natural products and their derivatives: Promising modulators of tumor immunotherapy

A wealth of evidence supports the role of tumor immunotherapy as a vital therapeutic option in cancer. In recent decades, accumulated studies have revealed the anticancer activities of natural products and their derivatives. Increasing interest has been driven toward finding novel potential modulators of tumor immunotherapy from natural products, a hot research topic worldwide. These works of research mainly focused on natural products, including polyphenols (e.g., curcumin, resveratrol), cardiotonic steroids (e.g., bufalin and digoxin), terpenoids (e.g., paclitaxel and artemisinins), and polysaccharide extracts (e.g., lentinan). Compelling data highlight that natural products have a promising future in tumor immunotherapy. Considering the importance and significance of this topic, we initially discussed the integrated research progress of natural products and their derivatives, including target T cells, macrophages, B cells, NKs, regulatory T cells, myeloid‐derived suppressor cells, inflammatory cytokines and chemokines, immunogenic cell death, and immune checkpoints. Furthermore, these natural compounds inactivate several key pathways, including NF‐κB, PI3K/Akt, MAPK, and JAK/STAT pathways. Here, we performed a deep generalization, analysis, and summarization of the previous achievements, recent progress, and the bottlenecks in the development of natural products as tumor immunotherapy. We expect this review to provide some insight for guiding future research.

Enhanced Prevention of Breast Tumor Metastasis by Nanoparticle-Delivered Vitamin E in Combination with Interferon-Gamma

Preventing cancer metastasis is one of the remaining challenges in cancer therapy. As an efficient natural product, alpha-tocopheryl succinate (α-TOS), the most effective form of vitamin E, holds great anticancer potential. To improve its efficacy and bioavailability, lipid-coated calcium carbonate/phosphate (LCCP) nanoparticles (NPs) with folic acid and PEG modification are synthesized for efficient delivery of α-TOS to 4T1 cancer cells. The optimized LCCP-FA NPs (NP-TOS15) show an α-TOS loading efficiency of around 60%, and enhanced uptake by 4T1 metastatic cancer cells. Consequently, NP-TOS15 significantly enhance the anticancer effect in combination with interferon-gamma (IFN-γ) in terms of apoptosis facilitation and migration inhibition. Importantly, NP-TOS15 upregulate the anticancer immunity via downregulating program death ligand 1 (PD-L1) expression that is initially induced by IFN-γ, and remarkably prevent the lung metastasis, particularly in combination with IFN-γ. Further investigation reveals that this combination therapy also modulates the cytotoxic lymphocyte infiltration into the tumor microenvironment for tumor elimination. Taken together, the NP delivery of α-TOS in combination with IFN-γ provides an applicable strategy for cancer therapy.

Myeloid-derived suppressor cells in hematological malignancies: friends or foes

Myeloid-derived suppressor cells (MDSCs) are newly identified immature myeloid cells that are characterized by the ability to suppress immune responses and expand during cancer, infection, and inflammatory diseases. Although MDSCs have attracted a lot of attention in the field of tumor immunology in recent years, little is known about their multiple roles in hematological malignancies as opposed to their roles in solid tumors. This review will help researchers better understand the various characteristics and functions of MDSCs, as well as the potential therapeutic applications of MDSCs in hematological malignancies, including lymphoma, multiple myeloma, leukemia, and hematopoietic stem cell transplantation.

RPN13/ADRM1 inhibitor reverses immunosuppression by myeloid-derived suppressor cells

Myeloid-derived-suppressor cells (MDSCs) are key mediators of immune suppression in the ovarian tumor microenvironment. Modulation of MDSC function to relieve immunosuppression may enhance the immunologic clearance of tumors. The bis-benzylidine piperidone RA190 binds to the ubiquitin receptor RPN13/ADRM1 on the 19S regulatory particle of the proteasome and directly kills ovarian cancer cells by triggering proteotoxic stress. Here we examine the effect of RA190 treatment on the immunosuppression induced by MDSCs in the tumor microenvironment, specifically on the immunosuppression induced by MDSCs. We show that RA190 reduces the expression of Stat3 and the levels of key immunosuppressive enzymes and cytokines arginase, iNOS, and IL-10 in MDSCs, while boosting expression of the immunostimulatory cytokine IL-12. Furthermore, we show that the RA190-treated MDSCs lost their capacity to suppress CD8+ T cell function. Finally, we show that RA190 treatment of mice bearing syngeneic ovarian tumor elicits potent CD8+ T cell antitumor immune responses and improves tumor control and survival. These data suggest the potential of RA190 for ovarian cancer treatment by both direct killing of tumor cells via proteasome inhibition and relief of MDSC-mediated suppression of CD8 T cell-dependent antitumor immunity elicited by the apoptotic tumor cells.

Metformin-Induced Reduction of CD39 and CD73 Blocks Myeloid-Derived Suppressor Cell Activity in Patients with Ovarian Cancer

Metformin is a broadly prescribed drug for type 2 diabetes that exerts antitumor activity, yet the mechanisms underlying this activity remain unclear. We show here that metformin treatment blocks the suppressive function of myeloid-derived suppressor cells (MDSC) in patients with ovarian cancer by downregulating the expression and ectoenzymatic activity of CD39 and CD73 on monocytic and polymononuclear MDSC subsets. Metformin triggered activation of AMP-activated protein kinase α and subsequently suppressed hypoxia-inducible factor α, which was critical for induction of CD39/CD73 expression in MDSC. Furthermore, metformin treatment correlated with longer overall survival in diabetic patients with ovarian cancer, which was accompanied by a metformin-induced reduction in the frequency of circulating CD39⁺CD73⁺ MDSC and a concomitant increase in the antitumor activities of circulating CD8⁺ T cells. Our results highlight a direct effect of metformin on MDSC and suggest that metformin may yield clinical benefit through improvement of antitumor T-cell immunity by dampening CD39/CD73-dependent MDSC immunosuppression in ovarian cancer patients.Significance: The antitumor activity of an antidiabetes drug is attributable to reduced immunosuppressive activity of myeloid-derived tumor suppressor cells. Cancer Res; 78(7); 1779-91. ©2018 AACR.

The Regulation of Pathways of Inflammation and Resolution in Immune Cells and Cancer Stem Cells by Selenium

Cancer is a complex disease where cancer stem cells (CSCs) maintain unlimited replicative potential, but evade chemotherapy drugs through cellular quiescence. CSCs are able to give rise to bulk tumor cells that have the capability to override antiproliferative signals and evade apoptosis. Numerous pathways are dysregulated in tumor cells, where increased levels of prooxidant reactive oxygen and nitrogen species can lead to localized inflammation to exacerbate all three stages of tumorigenesis: initiation, progression, and metastasis. Modulation of cellular metabolism in tumor cells as well as immune cells in the tumor microenvironment (TME) can impact inflammatory networks. Altering these pathways can potentially serve as a portal for therapy. It is well known that selenium, through selenoproteins, modulates inflammatory pathways in addition to regulating redox homeostasis in cells. Therefore, selenium has the potential to impact the interaction between tumor cells, CSCs, and immune cells. In the sections later, we review the current status of knowledge regarding this interaction, with reference to leukemia stem cells, and the importance of selenium-dependent regulation of inflammation as a potential mechanism to affect the TME and tumor cell survival.

Increased humoral immunity by DNA vaccination using an α-tocopherol-based adjuvant

DNA vaccines induce broad immunity, which involves both humoral and strong cellular immunity, and can be rapidly designed for novel or evolving pathogens such as influenza. However, the humoral immunogenicity in humans and higher animals has been suboptimal compared with that of traditional vaccine approaches. We tested whether the emulsion-based and α-tocopherol containing adjuvant Diluvac Forte® has the ability to enhance the immunogenicity of a naked DNA vaccine (i.e., plasmid DNA). As a model vaccine, we used plasmids encoding both a surface-exposed viral glycoprotein (hemagglutinin) and an internal non-glycosylated nucleoprotein in the Th1/Th2 balanced CB6F1 mouse model. The naked DNA (50 µg) was premixed at a 1:1 volume/volume ratio with Diluvac Forte®, an emulsion containing different concentrations of α-tocopherol, the emulsion alone or endotoxin-free phosphate-buffered saline (PBS). The animals received 2 intracutaneous immunizations spaced 3 weeks apart. When combined with Diluvac Forte® or the emulsion containing α-tocopherol, the DNA vaccine induced a more potent and balanced immunoglobulin G (IgG)1 and IgG2c response, and both IgG subclass responses were significantly enhanced by the adjuvant. The DNA vaccine also induced CD4+ and CD8+ vaccine-specific T cells; however, the adjuvant did not exert a significant impact. We concluded that the emulsion-based adjuvant Diluvac Forte® enhanced the immunogenicity of a naked DNA vaccine encoding influenza proteins and that the adjuvant constituent α-tocopherol plays an important role in this immunogenicity. This induction of a potent and balanced humoral response without impairment of cellular immunity constitutes an important advancement toward effective DNA vaccines.

The innate and adaptive infiltrating immune systems as targets for breast cancer immunotherapy

A cancer cell-centric view has long dominated the field of cancer biology. Research efforts have focussed on aberrant cancer cell signalling pathways and on changes to cancer cell DNA. Mounting evidence demonstrates that many cancer-associated cell types within the tumour stroma co-evolve and support tumour growth and development, greatly modifying cancer cell behaviour, facilitating invasion and metastasis and controlling dormancy and sensitivity to drug therapy. Thus, these stromal cells represent potential targets for cancer therapy. Among these cell types, immune cells have emerged as a promising target for therapy. The adaptive and the innate immune system play an important role in normal mammary development and breast cancer. The number of infiltrating adaptive immune system cells with tumour-rejecting capacity, primarily, T lymphocytes, is lower in breast cancer compared with other cancer types, but infiltration occurs in a large proportion of cases. There is strong evidence demonstrating the importance of the immunosuppressive role of the innate immune system during breast cancer progression. A consideration of components of both the innate and the adaptive immune system is essential for the design and development of immunotherapies in breast cancer. In this review, we focus on the importance of immunosuppressive myeloid-derived suppressor cells (MDSCs) as potential targets for breast cancer therapy.

Vitamin E-rich Nanoemulsion Enhances the Antitumor Efficacy of Low-Dose Paclitaxel by Driving Th1 Immune Response

PURPOSE

To overcome the drawbacks of high dose regimen and improve the outcomes of chemotherapy at a low dose, an immunotherapeutic nanoemulsion based combination of chemotherapeutic agent (paclitaxel) with immunomodulatory agent (vitamin E) was developed and evaluated for their antitumor effect against breast cancer.

METHODS

A total of five nanoemulsions loaded with various content of vitamin E were prepared and characterized. The immunoregulatory effects of vitamin E along with the overall antitumor efficacy of vitamin E-rich nanoemulsion with a low dose of paclitaxel were investigated through in vitro and in vivo experiments.

RESULTS

Vitamin E-rich nanoemulsion exhibited relatively narrow size distribution, high entrapment efficiency and controlled in vitro release profile. In RAW264.7 cells, vitamin E-rich nanoemulsion significantly enhanced the secretion of Th1 cytokines and down-regulated the secretion of Th2 cytokine. In a co-culture system, vitamin E-rich nanoemulsion induced a high apoptosis rate in MDA-MB-231 cells as compared with vitamin E-low nanoemulsion. Furthermore, vitamin E-rich nanoemulsion exhibited superior in vivo antitumor efficacy in comparison with Taxol and vitamin E-low nanoemulsion at a paclitaxel dose of 4 mg/kg.

CONCLUSIONS

Vitamin E-rich nanoemulsion has great potential for the treatment of breast cancers with a low dose of paclitaxel via driving Th1 immune response.

α-Tocopheryl Succinate Affects Malignant Cell Viability, Proliferation, and Differentiation

The widespread occurrence of malignant tumors motivates great attention to finding and investigating effective new antitumor preparations. Such preparations include compounds of the vitamin E family. Among them, α-tocopheryl succinate (vitamin E succinate (VES)) has the most pronounced antitumor properties. In this review, various targets and mechanisms of the antitumor effect of vitamin E succinate are characterized. It has been shown that VES has multiple intracellular targets and effects, and as a result VES is able to induce apoptosis in tumor cells, inhibit their proliferation, induce differentiation, prevent metastasizing, and inhibit angiogenesis. However, VES has minimal effects on normal cells and tissues. Due to the variety of targets and selectivity of action, VES is a promising agent against malignant neoplasms. More detailed studies in this area can contribute to development of effective and safe chemotherapeutic preparations.

Klotho sensitive regulation of dendritic cell functions by vitamin E

Background

Dendritic cells (DCs) are the most potent professional antigen-presenting cells for naive T cells to link innate and acquired immunity. Klotho, an anti-aging protein, participates in the regulation of Ca²⁺ dependent migration in DCs. Vitamin E (VitE) is an essential antioxidant to protect cells from damage and elicits its inhibitory effects on NF-κB-mediated inflammatory response. However, the roles of VitE on mouse DC functions and the contribution of klotho to those effects both are unknown. The present study explored the effects of VitE on klotho expression, maturation, ROS production and migration in DCs.

Methods

The mouse bone marrow cells were isolated and cultured with GM-CSF to attain bone marrow-derived DCs (BMDCs). Cells were stimulated with LPS (100 ng/ml) in the presence or absence of VitE (500 µM). RT-PCR and immunoprecipitation methods were employed to determine klotho expression, ELISA to determine cytokine release, flow cytometry to analyze number of CD86⁺CD11c⁺ cells, the intracellular expression of cytokines and reactive oxygen species (ROS) production and a transwell migration assay to trace migration.

Results

Klotho transcript level and this hormone secretion in DC supernatant were enhanced by VitE treatment and further increased in the presence of NF-κB inhibitor Bay 11-7082 (10 µM). Moreover, VitE treatment inhibited IL-12p70 protein expression of, ROS accumulation in and CCL21-dependent migration of LPS-triggered mature DCs, these effects were reversed following klotho silencing.

Conclusion

The up-regulation of klotho by VitE could contribute to the inhibitory effects of VitE on NF-κB-mediated DC functional maturation. The events might contribute to immunotherapeutic effect of VitE on the pathophysiology of klotho-related disease.

Toll-like receptor 3-induced immune response by poly(d,l-lactide-co-glycolide) nanoparticles for dendritic cell-based cancer immunotherapy

Dendritic cells (DCs) are potent professional antigen-presenting cells that are capable of initiating a primary immune response and activating T cells, and they play a pivotal role in the immune responses of the host to cancer. Prior to antigen presentation, efficient antigen and adjuvant uptake by DCs is necessary to induce their maturation and cytokine generation. Nanoparticles (NPs) are capable of intracellular delivery of both antigen and adjuvant to DCs. Here, we developed an advanced poly(d,l-lactide-co-glycolide) (PLGA)-NP encapsulating both ovalbumin (OVA) as a model antigen and polyinosinic-polycytidylic acid sodium salt (Toll-like receptor 3 ligand) as an adjuvant to increase intracellular delivery and promote DC maturation. The PLGA-NPs were taken up by DCs, and their uptake greatly facilitated major histocompatibility class I antigen presentation in vitro. Moreover, vaccination with PLGA-NP-treated DCs led to the generation of ovalbumin-specific CD8⁺ T cells, and the resulting antitumor efficacy was significantly increased in EG.7 and TC-1 tumor-bearing mice compared to control mice (P<0.01). Taken together, these findings demonstrated that the PLGA-NP platform may be an effective method for delivering tumor-specific antigens or adjuvants to DCs.

Reduction of Dacarbazine cytogenetic effects on somatic cells in male mice using bee glue (Propolis) to manifest the scientific miracles in the Quran

Objective

This study was carried out to investigate the ability of Propolis to ameliorate the adverse cytogenetic effects of Dacarbazine on bone marrow cells

Methods

In this experimental in vivo study, 18 mice were used, divided into four groups: control group; Propolis-treated group (treated with 50mg/kg Propolis); and Dacarbazine-treated group (treated with 3.5mg/kg Dacarbazine). The fourth, fifth, and sixth were treated with Dacarbazine and Propolis as pre 2h, post 2h, and concomitant treatment. After five days, the Bone Marrow (BM) samples were obtained for cytogenetic investigation.

Results

The in vivo studies revealed that Dacarbazine induced an abnormalities in polychromatic erythrocytes cells (PECs) as increase of cell with micronuclei, while the dual treatment accompanied with improvement of this abnormalities.

Conclusions

It could be concluded that there are protective effects of Propolis against the adverse effects of Dacarbazine. It could be recommended to use Propolis as an adjuvant with chemotherapeutic agents.

Protection against HPV-16-Associated Tumors Requires the Activation of CD8+ Effector Memory T Cells and the Control of Myeloid-Derived Suppressor Cells

Active anticancer immunotherapeutic approaches have been shown to induce cellular or humoral immune responses in patients, but, thus far, the observed outcomes did not ensure their recommendation for clinical use. The induction of tumor-specific CD8(+) T cells, although required for the clearance of most solid tumors, was shown to be insufficient for the development of a successful immunotherapeutic approach. The suppressive immune environment triggered by tumors, including the expansion of myeloid-derived suppressor cells (MDSC), is detrimental to the development of antitumor immune responses and precludes the generation of more promising clinical outcomes. In this work, we characterized the CD8(+) T-cell population specifically involved in the control of tumor growth and the role of MDSCs after administration of an antitumor therapeutic DNA vaccine targeting human papillomavirus type 16 (HPV-16)-associated tumors. Activation of cytotoxic high-avidity CD8(+) T cells with an effector memory phenotype was found in mice grafted with tumor cells expressing the HPV-16 oncoproteins. In addition, MDSC antibody depletion further enhanced the immunotherapeutic effects of the vaccine, resulting in the complete eradication of tumor cells. Collectively, the current results indicate that the simultaneous control of MDSCs and activation of high-avidity tumor-specific effector memory CD8(+) T cells are key features for tumor protection by immunotherapeutic approaches and deserve further testing under clinical conditions. Mol Cancer Ther; 15(8); 1920-30. ©2016 AACR.

Current state in the development of candidate therapeutic HPV vaccines

The identification of human papillomavirus (HPV) as an etiological factor for HPV-associated malignancies creates the opportunity to control these cancers through vaccination. Currently, available preventive HPV vaccines have not yet demonstrated strong evidences for therapeutic effects against established HPV infections and lesions. Furthermore, HPV infections remain extremely common. Thus, there is urgent need for therapeutic vaccines to treat existing HPV infections and HPV-associated diseases. Therapeutic vaccines differ from preventive vaccines in that they are aimed at generating cell-mediated immunity rather than neutralizing antibodies. The HPV-encoded early proteins, especially oncoproteins E6 and E7, form ideal targets for therapeutic HPV vaccines since they are consistently expressed in HPV-associated malignancies and precancerous lesions, playing crucial roles in the generation and maintenance of HPV-associated disease. Our review will cover various therapeutic vaccines in development for the treatment of HPV-associated lesions and cancers. Furthermore, we review strategies to enhance vaccine efficacy and the latest clinical trials on therapeutic HPV vaccines.

Effects of Antioxidants in Human Cancers: Differential Effects on Non-Coding Intronic RNA Expression

The notion that dietary antioxidants can help fight cancer is popular. However, the mechanism(s) behind the effect of antioxidants in cancer is still unclear. Previous studies indicate that supplements can influence gene expression; however, all of these studies were focused on the coding/exonic gene expression. Studies are now emerging to highlight critical functional roles for RNAs expressed from the non-coding regions. This project was designed to study the effect of antioxidant supplements on non-coding intronic RNA expression in human cancers. Vitamin E, N-Acetyl cysteine (NAC) and Sulforaphane are commonly used supplements to prevent diseases including cancers. We studied the effect of these antioxidant supplements on the non-coding intronic RNA expression using publicly available datasets from a mouse model for lung cancer and prostate cancer cell lines. Although high throughput polyA-enriched RNA-Seq data characterize spliced coding mRNA regions, recent studies reveal the expression of reads from the non-coding intronic regions. Our analyses indicate that cancer cells have higher expression of introns compared to that of normal cells and that treatment with antioxidant supplements reduces the increased expression of introns of several genes. However, we did find high expression of introns of multiple genes including many oncogenes in the supplement treated groups compared to that of the control; this effect was distinct depending on the cell type and the supplement studied. Using RT-PCRs, we validated the expression of introns of two oncogenes, DLK1 and LRG1, known to be key players in lung cancer progression, and demonstrate changed intronic expression with supplement treatment in cancer cells. With regard to the antioxidant system, supplements did not change the intronic RNAs for endogenous antioxidant enzymes except for a significant decrease in the expression of superoxide dismutase (SOD) intronic RNA. Concurrently, we also found that a prolonged (48 h) exposure to Vitamin C, Vitamin E and Green tea extract reduced the enzymatic activity of SOD in lung cancer cells. The results from this study reveal that the antioxidant supplements have a significant effect on the intronic RNA expression of many genes including cancer genes that are not directly linked to the body's antioxidant system. It is important to study this novel effect of antioxidant supplements in detail as it may have a significant role in disease progression.

Myeloid-derived suppressor cells as therapeutic target in hematological malignancies

Myeloid-derived suppressor cells (MDSC) are a heterogeneous population of immature myeloid cells that accumulate during pathological conditions such as cancer and are associated with a poor clinical outcome. MDSC expansion hampers the host anti-tumor immune response by inhibition of T cell proliferation, cytokine secretion, and recruitment of regulatory T cells. In addition, MDSC exert non-immunological functions including the promotion of angiogenesis, tumor invasion, and metastasis. Recent years, MDSC are considered as a potential target in solid tumors and hematological malignancies to enhance the effects of currently used immune modulating agents. This review focuses on the characteristics, distribution, functions, cell–cell interactions, and targeting of MDSC in hematological malignancies including multiple myeloma, lymphoma, and leukemia.