Synergistic effect of methionine encephalin (MENK) combined with pidotimod(PTD) on the maturation of murine dendritic cells (DCs)

The Opioid Growth Factor in Growth Regulation and Immune Responses in Cancer

It has become apparent that endogenous opioids act not only as neurotransmitters and neuromodulators, but have multiple functions in the body. Activation of the opioid system by opiate drugs is associated with a risk of cancer development through direct stimulation of tumor cell proliferation and through immunosuppression. In contrast, the endogenous peptide opioid [Met5]-enkephalin, now commonly referred to as Opioid Growth Factor (OGF), negatively regulates cell proliferation in a wide number of cells during development, homeostasis, and neoplasia. This action is mediated through the opioid growth factor receptor, originally designated the zeta (ζ) opioid receptor. Further, contrary to the traditional notion of opiates as immunosuppressive, endogenous OGF has been shown to possess a number of positive immunomodulatory properties and may provide a beneficial effect in cancer by augmenting the activity of cells involved in both innate and acquired immunity. Taken together, the evidence supports consideration of opioid peptides such as OGF as new strategies for cancer therapy.

Research Progress on the Mechanism of the Acupuncture Regulating Neuro-Endocrine-Immune Network System

As one of the conventional treatment methods, acupuncture is an indispensable component of Traditional Chinese Medicine. Currently, acupuncture has been partly accepted throughout the world, but the mechanism of acupuncture is still unclear. Since the theory of the neuro-endocrine-immune network was put forward, new insights have been brought into the understanding of the mechanism of acupuncture. Studies have proven that acupuncture is a mechanical stimulus that can activate local cell functions and neuroreceptors. It also regulates the release of related biomolecules (peptide hormones, lipid hormones, neuromodulators and neurotransmitters, and other small and large biomolecules) in the microenvironment, where they can affect each other and further activate the neuroendocrine-immune network to achieve holistic regulation. Recently, growing efforts have been made in the research on the mechanism of acupuncture. Some researchers have transitioned from studying the mechanism of acupuncture as a single linear pathway to using systems approaches, including metabolomics, genomics, proteomics and biological pathway analysis. This review summarizes the research progress on the neuro-endocrine-immune network related mechanism of acupuncture and discusses its current challenges and future directions.

Pidotimod enhanced the anti-growth effect of cisplatin on lung cancer in mice via promoting anti-tumor immune response

Cisplatin-based chemotherapeutics represent a mainstay of lung cancer therapy, but resistance limits their curative potential. In the current study, we reported that Pidotimod, which is an immunostimulant and used for the prevention of acute respiratory infections, elevated cisplatin sensitivity, leading to the synergistic attenuation of tumor growth in mouse lewis lung cancer (LLC) model. With further exploration, we found that Pidotimod enhanced the anti-growth effect of cisplatin on LLC via promoting anti-tumor response, such as increased infiltration of dendrite cells (DCs) and CD8⁺ T cells as well as enhancement of IFN-γ and Granzyme B expression. In summary, Pidotimod affects the anti-tumor function of cisplatin via promoting anti-tumor immune response and these findings provide a novel approach for the development of therapeutic strategies for lung cancer.

Prospective oncotarget for gynecological cancer: Opioid growth factor (OGF) - opioid growth factor receptor (OGFr) axis

The standard treatments for neoplasia include surgery, chemotherapy, hormone antagonists and radiotherapy, which can prolong survival, but rarely cure the tumors of gynecological cancer patients. OGF - OGFr expression, in various gynecologic cells and tissues, is an intersection point between cell development, neuroendocrine function and immune modulation. It has been identified that OGF and OGFr expression differs between gynecological tumor and normal cells. Further, exogenous or endogenous OGF and OGFr antagonists have been known to have a role in regulating cell viability and apoptosis. Moreover, the expression of proteins in the OGF - OGFr axis modulate differentiation and membrane expression of immune cells, which can enhance the immune response. In vivo and in vitro assays have shown that OGF and OGFr antagonists inhibit mitosis as well as induce apoptosis in gynecologic cancer cells. Although immune augmentation combination therapies can intensify cytotoxic activity, OGF or OGFr antagonists do not increase toxicities associated with dual-immune regulation. In conclusion, the OGF - OGFr axis provides significant strategies for antitumor efficiency in gynecological cancer.

Appropriate use of antibiotics: an unmet need

Increasing bacterial resistance combined with a steady decline in the discovery of new antibiotics has resulted in a global healthcare crisis. Overuse of antibiotics, for example, in the poultry and cattle industry, and misuse and improper prescription of antibiotics are leading causes of multidrug resistance (MDR). The increasing use of antibiotics, particularly in developing countries, is a big concern for antibiotic resistance and can cause other health threats such as increased risk of recurrent infections and increased risk of cardiovascular death with chronic use of macrolides. Carbapenems are the last line of defense in many cases of resistant infection, but trends show that resistance against these agents is also increasing. This narrative review is based on relevant literature according to the experience and expertise of the authors and presents an overview of the current knowledge on antibiotic resistance, the key driving factors, and possible strategies to tackle antibiotic resistance. Collectively, studies show that hospital-wide antibiotic stewardship programs are effective in decreasing the spread of antibacterial resistance. As resistance varies according to local patterns of use, it is essential to observe the epidemiology at both a regional and an institutional level. Furthermore, adaptation of clinical guidelines is necessary, particularly for inpatient care. Future guidelines should include a justification step for continued treatment of antibiotic treatments and criteria for selection of antibiotics at the start of treatment. Nonantibiotic prevention strategies can limit infections and should also be considered in treatment plans. Vaccines against MDR organisms have shown some efficacy in phase II trials in critical care patients. Nonimmunogenic and microbiologic treatment options such as fecal transplants may be particularly important for elderly and immune-compromised patients.

Methionine enkephalin (MENK) inhibits human gastric cancer through regulating tumor associated macrophages (TAMs) and PI3K/AKT/mTOR signaling pathway inside cancer cells

This study was to explore the effect and mechanisms of anti- human gastric cancer by MENK in vitro and in vivo. The results showed in MENK-treated xenograft tissue, the percentage of M2-type macrophages decreased while M1-type macrophages increased. MENK increased the expression of M1-related cytokine TNF-α and attenuated the expression of M2-related cytokine IL-10 expression. MENK upregulated the expression of opioid receptor (OGFr), while it inhibited HGC27 and SGC7901 cells through blocking PI3K/AKT/mTOR signal pathway in vitro and in vivo. These effects of MENK could be cancelled when OGFr was knockdown. This indicates that binding to OGFr by MENK appears to be essential for the anti- GC cells. Therefore, it is concluded that MENK might skew macrophage toward M2 phenotype from M1 phenotype within tumor and induce cells apoptosis though blocking OGFr/PI3K/AKT/mTOR signaling pathway.

The novel mechanism of anticancer effect on gastric cancer through inducing G0/G1 cell cycle arrest and caspase-dependent apoptosis in vitro and in vivo by methionine enkephalin

Background

Gastric cancer (GC) is the second cause of cancer-related deaths. Methionine enkephalin (MENK), an endogenous opioid peptide, has immunological and antitumor activity.

Purpose

The aim of this work was to investigate whether MENK could exhibit activity against human GC in vitro and in vivo.

Materials and methods

Human GC cells were treated with MENK. Cell viability, colony formation, cell morphology, cell cycle, and apoptosis were assessed. The effects of MENK on gene expression of OGFr, Bax, BCL-2, caspase-3, PARP, Ki67, cyclin D1, c-myc, survivin were quantifed by qRT-PCR. Western blot was used to analyze the effects of MENK on protein expression of OGFr, Bax, BCL-2, caspase-3, PARP. The anti-tumor activity of MENK in gastic carcinoma was also investigated with animal experiments.

Results

The results indicate that MENK could significantly inhibit the growth of human GC cells SGC7901 and HGC27 in a concentration- and time-dependent manner, decrease the number of cell colonies, and arrest cell cycle in the G0/G1 phase by causing a decrease in Ki67, cyclin D1, and c-myc mRNA. Furthermore, MENK could induce tumor cell apoptosis associated with the upregulation of Bax, a corresponding downregulation of BCL-2 and survivin, and activation of caspase-3 and PARP. Moreover, MENK upregulated the expression of opioid receptors (OGFr) in SGC7901 and HGC27 cells. The interaction between MENK and OGFr in SGC7901 and HGC27 cells appears to be essential for the antitumor activity of MENK.

Conclusion

We conclude that MENK may be a potential drug for the treatment of GC.

A novel modulation of structural and functional changes of mouse bone marrow derived dendritic cells (BMDCs) by interleukin-2(IL-2)

IL-2 is a pleiotropic cytokine produced by T cell after antigen activation of T cell and it is so called T cell growth factor. A large number of documents suggest that Il-2 plays pivotal roles in the immune response and now Il-2 is an approved drug being used for various kinds of diseases such as cancer and dermatitis. (1) The aim of present exploration was to look at effect of IL-2 on structural, phenotypic and functional maturation of murine BMDCs. The structural and phenotypic maturation of BMDCs under influence of IL-2 were evaluated by light microscope and flow cytometry (FCM). The functional maturation of BMDCs was confirmed by cytochemistry assay, FITC-dextran, acid phosphatase (ACP) activity, bio-assay and enzyme linked immunosorbent assay (ELISA).We elucidated that IL-2 up-regulated the expression of key surface markers such as: CD80, CD83, CD86, CD40 and MHC II molecules on BMDCs, down-regulated phagocytosis activity, induced more production of IL-12 and TNF-α secreted by BMDCs. Therefore it can be concluded that IL-2 effectively enhance the maturation of BMDCs. Our results provide direct evidence to support IL-2 would be used as a potent adjuvant in preparation of DC-based vaccines, as well as an immune remedy for cancer situation.

Methionine enkephalin (MENK) improves lymphocyte subpopulations in human peripheral blood of 50 cancer patients by inhibiting regulatory T cells (Tregs)

MENK, a penta-peptide is considered as being involved in the regulatory feedback loop between the immune and neuroendocrine systems, with marked modulation of various functions of human immune cells. The aim of the present work was to investigate change of lymphocyte subpopulations in peripheral blood of 50 cancer patients before and after treatment with MENK. Peripheral blood mononuclear cells (PBMCs) of peripheral blood from 50 cancer patients were isolated by density gradient centrifugation using Ficoll-Paque solution and cultured with MENK. We measured proliferation of total nucleated cells, subpopulations of individual CD4+T cells, CD8+T cells, CD4+CD25+ regulatory T cells (Treg), natural killer cells (NK) before and after treatment with 10(-12)M MENK in cell culture by flow cytometry (FCM). Our results indicated that MENK showed a strong inhibiting effect on Treg cells while it stimulated marked proliferation of other lymphocyte subpopulations. All data obtained were of significance statistically. It was therefore concluded that MENK could work as a strong immune booster with great potential in restoring damaged human immune system and we could consider MENK as a drug to treat cancer patients, whose immune systems are damaged by chemotherapy or radiotherapy. Furthermore we could consider MENK as a chemotherapy additive, which would sustain immune system of cancer patients during the process of chemotherapy to get maximized efficacy with minimized side effect.

Endogenous opiates and behavior: 2013

This paper is the thirty-sixth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2013 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia; stress and social status; tolerance and dependence; learning and memory; eating and drinking; alcohol and drugs of abuse; sexual activity and hormones, pregnancy, development and endocrinology; mental illness and mood; seizures and neurologic disorders; electrical-related activity and neurophysiology; general activity and locomotion; gastrointestinal, renal and hepatic functions; cardiovascular responses; respiration and thermoregulation; and immunological responses.

Low dose naltrexone (LDN) enhances maturation of bone marrow dendritic cells (BMDCs)

It has been demonstrated previously that immune cell activation and proliferation were sensitive to the effects of naltrexone, a non-peptidic δ-opioid receptor selective antagonist and opioid receptors on BMDCs have been detected [1]. However, there is little prior data published on naltrexone and DCs. Therefore, we hypothesized that LDN could exert modulating effect on BMDCs. In present study, we studied influence of LDN on both phenotypic and functional maturation of BMDCs. Changes of BMDC post-treatment with LDN were evaluated using conventional light microscope and transmission electron microscopy (TEM); flow cytometry(FCM); cytochemistry; acid phosphatase activity(ACP) test; FITC-dextran bio-assay; mixed lymphocytes and enzyme-linked immunosorbent assay (ELISA). We have found that LDN enhances maturation of BMDCs as evidenced by 1) up-regulating the expression of MHC II, CD40, CD83, CD80 and CD86 molecules on BMDCs; 2) down-regulating the rates of pinocytosis and phagocytosis accompanied by the results of decreased ACP, and FITC-dextran bio-assay; 3) mounting potential of BMDCs to drive T cell; and 4) inducing secretion of higher levels of IL-12 and TNF-α. It is therefore concluded that LDN can efficiently promote the maturation of BMDCs via precise modulation inside and outside BMDCs. Our study has provided meaningful mode of action on the role of LDN in immunoregulation, and rationale on future application of LDN for enhancing host immunity in cancer therapy and potent use in the design of DC-based vaccines for a number of diseases.

The novel role of thymopentin in induction of maturation of bone marrow dendritic cells (BMDCs)

Thymopentin is an immune-modulating peptide that can stimulate cellular immune responses and has been used in many immune handicapped cases [1]. However, despite documented reports proving its efficacy in immunoregulation, there have been no reports, as yet, concerning its impact on the maturation and function of dendritic cells (DCs). In this study, we analyzed the effects of thymopentin on the detailed regulation of maturation of murine bone-marrow-derived DCs (BMDCs). The phenotypic and structural maturation of BMDCs was confirmed by transmission electron microscopy (TEM) and flow cytometry (FCM). The functional maturation was confirmed by an acid phosphatase (ACP) activity test, FITC-dextran bio-assay, test of 5,6-carboxyfluorescein diacetate succinimidyl ester (CFSE), labeled CD4(+)T cell proliferation and enzyme-linked immunosorbent assay (ELISA). We determined that thymopentin up-regulated the expression of CD40, CD80, CD86, CD83, and MHC II molecules on BMDCs, down-regulated phagocytosis of BMDCs, increased BMDCs driven CD4(+)T cell proliferation, and enhanced BMDC production of IL-12 and TNF-α. Therefore, we concluded that thymopentin highly induces BMDC maturation and intensifies DC/T-cell pathways. These data also provide direct evidence and rationale concerning the potential clinical use of thymopentin in various immune handicapped cases and suggest that thymopentin should be considered as a potent adjuvant for DC-based vaccines.

Maturation inside and outside bone marrow dendritic cells (BMDCs) modulated by interferon-α (IFN-α)

Interferons are made by cells in response to appropriate stimuli such as viruses, bacteria, parasites or tumor cells and are released into the surrounding medium. They then bind to receptors on target cells to allow for communication between cells to trigger the protective defenses of the immune system that eradicate pathogens or tumors. IFN-α is produced by leukocytes and is mainly involved in innate immune response against viral or bacterial infections and for tumor control. The aim of this work is to explore the detailed modulation of IFN-α on phenotypic and functional maturation inside and outside murine bone marrow derived dendritic cells (BMDCs). The maturity of BMDCs post treatment with IFN-α was evaluated with conventional light microscope and transmission electron microscopy (TEM) for morphology changes; flow cytometry (FCM) for changes of surface molecules on BMDCs; cytochemistry, acid phosphatase activity (ACP) test, and FITC-dextran bio-assay for biochemistry analysis and enzyme-linked immunosorbent assay (ELISA) for cytokine production by BMDCs. We have shown that IFN-α 1) up-regulates the expression of MHC II, CD40, CD83, CD80 and CD86 molecules on BMDCs; 2) down-regulates the rates of pinocytosis and phagocytosis by BMDCs as evidenced by the results of decreased ACP, and FITC-dextran bio-assay; 3) enhances the ability of BMDCs to drive T cell function; and 4) induces higher levels of IL-12 and TNF-α secreted by BMDCs. Therefore, we conclude that IFN-α can efficiently promote the maturation of BMDCs through detailed modulation inside and outside BMDCs. Our study has provided more detailed data on changes of BMDCs modulated by IFN-α, and rationale on future application of IFN-α for enhancing host immunity and potent adjuvant administration in the design of DC-based vaccines.

Detailed modulation of phenotypes and functions of bone marrow dendritic cells (BMDCs) by interferon-gamma (IFN-γ)

IFN-γ is a cytokine that plays crucial role in innate and adaptive immunity against viral and intracellular bacterial infections and for tumor control. IFN-γ is also a key activator of macrophages [1,2]. In the present study, we studied detailed modulation of IFN-γ on phenotypic and functional maturation of murine bone marrow derived dendritic cells (BMDCs). Phenotypic and functional maturation of BMDCs was evaluated by light microscope, flow cytometry(FCM), transmission electron microscopy (TEM), cytochemistry method, acid phosphatase activity(ACP), FITC-dextran bio-assay and enzyme linked immunosorbent assay (ELISA). We elucidated that IFN-γ up-regulated the expression of MHC II, CD40, CD80, CD83 and CD86 molecules on BMDCs, down-regulated the activity of pinocytosis and phagocytosis by BMDCs, and induced higher levels of IL-12 and TNF-α secreted by BMDCs. It is therefore confirmed that IFN-γ can effectively promote the maturation of BMDCs. Our study provides more evidence and rationale on future application of IFN-γ for enhancing host immunity.