Targeting the tumor microenvironment by liposomal Epacadostat in combination with liposomal gp100 vaccine.

Indoleamine-2,3-dioxygenase (IDO1) pathway has vital role in cancer immune escape and its upregulation leads to immunosuppressive environment which is associated with poor prognosis and progression in various cancers like melanoma. Previously, we showed the antitumoral efficacy of nanoliposomal form of Epacadostat (Lip-EPA), as an IDO1 inhibitor. Herein, we used Lip-EPA as a combination approach with liposomal gp100 (Lip-gp100) anti-cancer vaccine in melanoma model. Here, we showed that B16F10 tumor express IDO1 so using Lip-EPA will enhance the efficacy of vaccine therapy. The biodistribution of ICG-labelled liposomal form of EPA showed the remarkable accumulation of drug at tumor site. In an in vivo study, Lip-EPA enhanced the antitumor efficacy of Lip-gp100 in which the IDO mRNA expression was decreased (~ fourfold) in tumor samples. Also, we identified a significant increase in the number of infiltrated T lymphocytes (p < 0.0001) with enhanced in interferon gamma (IFN-γ) production (p < 0.0001). Additionally, Lip-EPA + Lip-gp100 significantly modulated intratumoral regulatory T cells which altogether resulted in the highest delay in tumor growth (TGD = 56.54%) and increased life span (ILS > 47.36%) in treated mice. Our study demonstrated that novel combination of Lip-EPA and Lip-gp100 was effective treatment with capability of being used in further clinical studies.

Anti-Proliferative Potential of Fluorinated Curcumin Analogues: Experimental and Computational Analysis and Review of the Literature.

BACKGROUND: Curcuminoids, flavoring, and coloring agents in food have potent antioxidant, anti-tumor activity, and anti-inflammatory effects. However, they are rapidly metabolized to lesser active metabolites. Therefore, various studies have been conducted to synthesize new and stable curcumin analogues with enhanced therapeutic activity. METHODS: Fluorinated curcumin compounds (2a-2f) were synthesized by Knoevenagel condensation between fluorobenzaldehydes (1a-1f) with curcumin. Fluorinated demethoxycurcumin (3a) was synthesized by condensation between demethoxycurcumin and 3,4-difluorobenzaldehyde (1f). The structures of these compounds were confirmed by FTIR, 1H-NMR, 13C-NMR, 19FNMR, and mass spectroscopy. Antiproliferative activities of these synthetic compounds were evaluated against breast cancer cells (4T1), melanoma cancer cells (B16F10), and normal cell lines (NIH 3T3) using MTT assay. The interaction of curcumin, 2f and 3a with several proteins (1HCL, 2ZOQ, 3D94, 5EW3, 4WA9, 1XKK, 6CCY) was investigated. The structural preservation of the epidermal growth factor receptor (EGFR) was investigated by molecular dynamics simulation. RESULTS: The spectroscopic data obtained confirmed the proposed structure of fluorinated analogues. The results showed that compounds 2f and 3a inhibited cancer cells proliferation significantly more than other compounds. Compounds 2f and 3a showed the highest affinity and lowest binding energy with EGFR. The binding energies were -7.8, -10, and - 9.8 kcal/mol for curcumin, 2f and 3a with EGFR, respectively. The molecular docking results demonstrated that compounds 2f and 3a were firmly bound in a complex with EGFR via the formation of a hydrogen bond. CONCLUSION: In summary, we found that fluorinated demethoxycurcumin and fluorinated curcumin induces cancer cell death and binds to EGFR with high affinity.

pH-Sensitive PEGylated Liposomal Silybin: Synthesis, In Vitro and In Vivo Anti-Tumor Evaluation.

The drug delivery systems improve the efficacy of chemotherapeutics through enhanced targeting and controlled release however, biological barriers of tumor microenvironment greatly impede the penetration of nanomedicine within the tumor. We report herein the fabrication of a PEG-detachable silybin (SLB) pH-sensitive liposome decorated with TAT-peptide. For this, Acyl hydrazide-activated PEG2000 was prepared and linked with ketone-derivatized DPPE via an acid-labile hydrazone bond to form mPEG2000-HZ-DPPE. TAT peptide was conjugated with a shorter -PEG1000-DSPE spacer and post-inserted into PEGylated liposome (DPPC: mPEG2000-DSPE: Chol). To prepare nanoliposomes (around 100 nm), first, a novel method was used to prepare SLB-Soya PC (SLB-SPC) complex, then this complex was incorporated into nanoliposomes. The pH-sensitivity and shielding effect of long PEG chain on TAT peptide was investigated using DiI liposome and FACS analysis. Pre-treatment to the lowered pH enhanced cellular association of TAT-modified pH-sensitive liposome due to the cleavage of hydrazone bond and TAT exposure. Besides, TAT-modified pH-sensitive liposomes significantly reduced cell viability compared to the plain liposome. In vivo results were very promising with pH-sensitive liposome by detaching PEG moieties upon exposure to the acidic tumor microenvironment, enhancing cellular uptake, retarding tumor growth, and prolonging the survival of 4T1 breast tumor-bearing BALB/c mice. TAT modification of pH-sensitive liposome improved cancer cell association and cytotoxicity and demonstrated potential intracellular delivery upon exposure to acidic pH. However, in in vivo studies, TAT as a targeting ligand significantly decreased the therapeutic efficacy of the formulation attributed to an inefficient tumor accumulation and higher release rate in the circulation. The results of this study indicated that pH-sensitive liposome containing SLB, which was prepared with a novel method with a significant SLB loading efficiency, is very effective in the treatment of 4T1 breast tumor-bearing BALB/c mice and merits further investigation.

Improvement of the pharmacokinetic characteristics of liposomal doxorubicin using CD47 biomimickry.

OBJECTIVES: In view of their biodegradability, biocompatibility, encapsulation efficiency and targeted release, as well as low toxicity, liposomes are being widely used in the context of drug delivery. However, the efficiency of such drug delivery systems might face limitations by macrophage-mediated clearance (CL), which reduces circulation half-life (T½). This problem can be resolved through surface functionalization via poly (ethylene glycol) (PEG) in the process of PEGylation. However, the use of PEG might have its own disadvantages. Accordingly, the main purpose of this study was to produce novel stealth nanoliposomes using CD47 mimicry peptide [namely self-peptide (SP)] as an alternative to PEG for minimizing macrophage-mediated CL and enhancing circulation T½. METHODS: At first, doxorubicin (Dox)-containing liposomes [i.e.liposomal Dox (LD)] were coated with different concentrations of SP (viz. SP-LD) (0.5%, 1% and 2%). In addition, PEG-functionalized LD (i.e. PLD) was fabricated as a standard control group. Then, various types of liposomal formulae were injected into a population of mice, assigned to six groups (four mice per group) for biodistribution. After sacrificing these animals in prespecified time points (namely 0.5, 6, 12, 24, 48, 72, 96 and 168 h), serum, liver, spleen, heart, kidney and lung samples were collected to estimate the encapsulated drug content in different groups through measuring intrinsic autofluorescence signal of Dox. KEY FINDINGS: The tissue distribution results in the liver, spleen, heart, kidney and lung samples indicated a significant difference between the SP-LD and the PLD groups. Furthermore, the examination of Dox content, 6 h after administration, showed a growth rate of 28% in Dox content in the SP group compared with the PLD one. Subsequently, these values were, respectively, 63% and 75% at 24 and 48 h. CONCLUSIONS: The results of tissue distribution and serum kinetic analysis correspondingly revealed that the use of the SP could augment the circulation time of Dox in comparison with PEG, and it could additionally minimize the tissue accumulation of the drug, which is normally the cause of drug-induced toxicity. The use of the SP on nanoliposomes could prolong the circulation of T½ and diminish the tissue accumulation of LD. These findings are relevant for improving therapeutic efficacy and reducing the toxicity of liposomal drugs.

Anti-Tumor Efficacy of Pyrvinium Pamoate Nanoliposomes in an Experimental Model of Melanoma.

BACKGROUND: Pyrvinium Pamoate (PP) is an old drug approved by the FDA for the treatment of pinworm infections. Recently, it has been introduced as an anti-tumor agent, however, low aqueous solubility severely limits its potential effects. In this study, we developed a liposomal formulation of pyrvinium pamoate to investigate its in vitro cytotoxicity and in vivo efficacy against melanoma cells. MATERIALS & METHODS: As drug carriers, liposomes were fabricated using the thin-film method. PP was encapsulated within the liposomes using a remote loading method. We evaluated the morphology, particle size, and Zeta potential of the liposomes. Additionally, High-Performance Liquid Chromatography (HPLC) was employed for qualitative and quantitative analysis. Then we investigated our liposomal PP for its in vitro cytotoxicity as well as the tumor growth inhibition in C57BL/6 mice bearing B16F0 melanoma tumors. RESULTS: Based on the analytical result, the liposomal drug delivery system is a homogeneous and stable colloidal suspension of PP particles. The images of Atomic force microscopy and particle size data showed that all the prepared nanocarriers were spherical with a diameter of approximately 101 nm. According to both in vitro and in vivo studies, nanoliposomal PP exhibited an improved anti-proliferative potential against B16F10 melanoma tumor compared to free PP. CONCLUSION: Liposomal encapsulation improves the water solubility of PP and enhances its anti-cancer activity.

Liposomal gp100 vaccine combined with CpG ODN sensitizes established B16F10 melanoma tumors to anti PD-1 therapy.

OBJECTIVES: Program death 1 (PD-1)/ program death-ligand 1 (PD-L1) pathways, as the main inhibitory checkpoints, induce immunosuppression in the tumor microenvironment (TME). Despite the importance of inhibitor checkpoint receptor (ICR) blockers, their outcomes have been limited by the low immune response rate and induced acquired resistance. Pre-existing tumor-specific T cells is related to the improvement of their therapeutic efficacy. In the present study, we show that the combination of liposomal gp100 nanovaccine with anti PD-1 monoclonal antibody (mAb) potentiates the therapeutic effect in the melanoma model. MATERIALS AND METHODS: In this study, we first decorate the cationic liposome with gp10025-33 self-antigen and then characterize it. Mice bearing B16F10 melanoma tumors were vaccinated with different formulations of gp100 peptide (free or liposomal form) with or without CpG ODN adjuvant in combination with anti PD-1 mAb. RESULTS: Therapeutic combination of liposomal nanovaccine and CpG with anti PD-1 mAb, demonstrated the increased number of tumor infiltrated lymphocytes (TILs) in TME with the highest IFN-γ production and cytotoxic activity, which led to remarkable tumor regression. CONCLUSION: Our results demonstrated the synergism between Lip-peptide+CpG nanovaccine and anti PD-1 regime, which improved the therapeutic efficacy of PD-1 checkpoint blocker in melanoma mice models.

Vaccination with dendritic cells pulsed ex vivo with gp100 peptide-decorated liposomes enhances the efficacy of anti PD-1 therapy in a mouse model of melanoma.

BACKGROUND: Targeting antigens to dendritic cells (DCs) via nanoparticles is a powerful strategy which improves the efficacy of ex vivo antigen-pulsed DC vaccines. METHODS: In this study, liposomes were first decorated with gp10025-33 self-antigen and then characterized. Then, DCs were pulsed ex vivo with liposomal gp100 and injected subcutaneously in mice bearing B16F10 established melanoma tumors in combination with anti-PD-1 therapy. RESULTS: Treatment with liposomal pulsed DC vaccine elicited the strongest anticancer immunity and enhanced intratumoral immune responses based on infiltration of gp100-specific CD4+ and CD8+ T cells to the tumor leading to significant tumor growth regression and prolonged survival rate. Treatment with liposomal pulsed DC vaccine also markedly enhanced specific cytotoxic T lymphocytes (CTL) responses with a significant higher titer of IFN-γ in the spleen. Moreover, a significant increase of PD-1 expressing CD8+ tumor infiltrating lymphocytes (TILs) was detected in tumors. CONCLUSION: Our results demonstrate an optimum dose of liposomal gp100 significantly increases the efficacy of anti-PD-1 therapy in mice and might be an effective strategy to overcome resistance to anti-PD-1 therapy.

Harnessing CD47 mimicry to inhibit phagocytic clearance and enhance anti-tumor efficacy of nanoliposomal doxorubicin.

BACKGROUND: We hypothesized if phagocytosis of liposomes by macrophages could be mitigated through incorporation of a CD47 mimicry peptide (Self peptide: SP) on the surface of liposomes. METHODS: Thin film hydration method followed by extrusion was used to prepare nanoliposomes, and Dox encapsulation in liposomes was done via remote-loading method. Decorated liposomes with SP peptide (SP-LD) at different peptide densities (300 and 600 peptides on the surface of each liposome) were prepared using a pre-insertion technique. Macrophage cell lines were used to compare the cellular uptake of decorated and unmodified liposomes. For biodistribution studies, tumor-bearing mice received the preparations, and fluorescence signals of Dox in different tissues were measured. To evaluate anti-tumor efficacy, tumor size and survival rates were assessed. Also, pharmacokinetic parameters were determined. RESULTS: Compared with PEGylated liposomes, uptake by macrophages was largely decreased when SP was incorporated on liposomes. Following intravenous injection, SP-liposomes were cleared more slowly compared with PEGylated liposomes. Eventually, SP-liposomes were highly distributed to tumor tissues compared with PEGylated liposomes, and significantly reduced tumor size and improved the survival of tumor-bearing mice. CONCLUSIONS: This research showed reduced macrophage uptake, increased blood circulation, and enhanced tumor accumulation of liposomes through SP incorporation on the surface of particles.

Liposome Circulation Time is Prolonged by CD47 Coating.

INTRODUCTION: Bio-degradable nano-particles have many applications as drug delivery vehicles because of their good bio-availability, controlled release, low toxicity and potential for encapsulation. However, the most important obstacle to nanoparticulate drug delivery is elimination by macrophages which reduces the residence time of nanoparticles in the blood. To overcome this problem, the surface of the nanoparticle can be passivated by coating with Polyethylene glycol (PEG). However, the use of PEG has its own disadvantages. CD47 receptor acts as a self marker on the surface of many cells and inhibits phagocytosis. This study used a CD47 mimicry peptide as a substitute for PEG to fabricate "stealth" nanoliposome with reduced macrophage clearance. METHODS: Doxorubibin was used as a model drug because of its inherent fluorescence. Doxorubicin- containing liposomes were coated with different percentages of CD47 mimicry peptide (0.5% and 1%). PEG-functionalized doxorubicin-containing liposomes, were used as a comparator. The liposomal formulations were intravenously injected into mice. Serum was collected at pre-defined time points and tissue samples were taken at 24 hours. Fluorescence was used to determine the concentration doxorubicin in serum, heart, spleen, kidney, liver and lung tissues. RESULTS: Tissue biodistribution and serum kinetic studies indicated that compared with PEG, the use of CD47 mimicry peptide increased the circulation time of doxorubicin in the circulation. Moreover, unwanted accumulation of doxorubicin in the reticuloendothelial tissues (liver and spleen), kidney and heart was significantly decreased by the CD47 mimicry peptide. CONCLUSION: The use of a CD47 mimicry peptide on the surface of nanoliposomes improved the residence time of liposomal doxorubicin in the circulation. The accumulation of drug in non-target tissues was reduced, thereby potentially reducing toxicity.

Author Correction: Liposomal formulation of Galbanic acid improved therapeutic efficacy of pegylated liposomal Doxorubicin in mouse colon carcinoma.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Evaluation of the Anti-Tumor Activity of Niclosamide Nanoliposomes Against Colon Carcinoma.

BACKGROUND AND AIMS: Niclosamide is an established anti-helminthic drug, which has recently been shown to inhibit the growth of various cancer cells. To exploit the potential anti-tumor activity of this drug for systemic use, the problem of low aqueous solubility should be addressed. The present study tested the in vivo anti-tumor effects of a recently developed nanoliposomal preparation of niclosamide in an experimental model of colon carcinoma. METHODS: The cytotoxicity of nanoliposomal niclosamide on CT26 colon carcinoma cells was evaluated using the MTT test. Inhibition of tumor growth was investigated in BALB/c mice bearing CT26 colon carcinoma cells. The animals were randomly divided into 4 groups including: 1) untreated control, 2) liposomal doxorubicin (15 mg/kg; single intravenous dose), 3) liposomal niclosamide (1 mg/kg/twice a week; intravenously for 4 weeks), and 4) free niclosamide (1 mg/kg/twice a week; intravenously for 4 weeks). To study therapeutic efficacy, tumor size and survival were monitored in 2-day intervals for 40 days. RESULTS: In vitro results indicated that nanoliposomal and free niclosamide could exert cytotoxic effects with IC50 values of 4.5 and 2.5 µM, respectively. According to in vivo studies, nanoliposomal niclosamide showed a higher growth inhibitory activity against CT26 colon carcinoma cells compared with free niclosamide as revealed by delayed tumor growth and prolongation of survival. CONCLUSION: Nnaoliposomal encapsulation enhanced anti-tumor properties of niclosamide in an experimental model of colon carcinoma.

CD47: role in the immune system and application to cancer therapy.

BACKGROUND: CD47 is a widely expressed cellular receptor well known for its immunoregulatory functions. By interacting with its ligands, including thrombospondin-1 (TSP-1), signal regulatory protein α (SIRPα), integrins, and SH2-domain bearing protein tyrosine phosphatase substrate-1 (SHPS-1), it modulates cellular phagocytosis by macrophages, transmigration of neutrophils and activation of dendritic cells, T cells and B cells. Ample studies have shown that various types of cancer express high levels of CD47 to escape from the immune system. Based on this observation, CD47 is currently considered as a prominent target in cancer therapy. CONCLUSIONS: Here, we review the role of CD47 in the maintenance of immune system homeostasis. We also depict three emerging CD47-targeting strategies for cancer therapy, including the use of mimicry peptides, antibodies, and gene silencing strategies. Among these approaches, the most advanced one is the use of anti-CD47 antibodies, which enhances cancer cell phagocytosis via inhibition of the CD47-SIRPα axis. These antibodies can also achieve higher anti-cancer efficacies when combined with chemotherapy and immunotherapy and hold promise for improving the survival of patients with cancer.

Development of a topical liposomal formulation of Amphotericin B for the treatment of cutaneous leishmaniasis.

BACKGROUND: Currently, there is no topical treatment available for any form of cutaneous leishmaniasis (CL) in most of the endemic areas. The aim of the current study was to develop a topical nano-liposomal Amphotericin B (AmB) for the treatment of CL. METHODOLOGY/PRINCIPAL FINDINGS: Liposomes containing 0.1, 0.2 and 0.4% AmB (Lip-AmB) were formulated and characterized for the size, entrapment efficiency, long term stability, and skin penetration properties using Franz diffusion cells. Liposomes diameters were around 100 nm with no change during more than 20 months' storage either at 4 °C or at room temperature. Franz diffusion cells studies showed that almost 4% of the applied formulations penetrated across the skin and the highest skin retention (73.92%) observed with Lip-AmB 0.4%. The median effective doses (ED50), the doses of AmB required to kill 50% of L. major amastigotes were 0.151, 0.151, and 0.0856 (µg/mL) in Lip-AmB 0.1, 0.2, 0.4%, respectively. Lip-AmB 0.4% caused 80% reduction in fluorescence intensity of GFP+ L. tropica infected macrophages at 5 µg/mL of AmB concentration. Topical Lip-AmB was applied twice a day for 4 weeks to the skin of BALB/c mice to treat lesions caused by L. major. Results showed the superiority of Lip-AmB 0.4% compared to Lip-AmB 0.2 and 0.1%. The parasite was completely cleared from the skin site of infection and spleens at week 8 and 12 post-infection in mice treated with Lip-AmB 0.4%. The results suggest that topical Lip-AmB 0.4% may be a useful tool in the treatment of CL and merits further investigation.

Demethoxycurcumin: A naturally occurring curcumin analogue for treating non-cancerous diseases.

Turmeric extracts contain three primary compounds, which are commonly referred to as curcuminoids. They are curcumin, demethoxycurcumin (DMC), and bisdemethoxycurcumin. While curcumin has been the most extensively studied of the curcuminoids, it suffers from low overall oral bioavailability due to extremely low absorption as a result of low water solubility and instability at acidic pH, as well as rapid metabolism and clearance from the body. However, DMC, which lacks the methoxy group on the benzene ring of the parent structure, has much greater chemical stability at physiological pH and has been recently reported to exhibit antitumor properties. However, the treatment of noncancerous diseases with DMC has not been comprehensively reviewed. Therefore, here we evaluate published scientific literature on the therapeutic properties of DMC. The beneficial pharmacological actions of DMC include anti-inflammatory, neuroprotective, antihypertensive, antimalarial, antimicrobial, antifungal, and vasodilatory properties. In addition, DMC's ability to ameliorate the effects of free radicals and an environment characterized by oxidative stress caused by the accumulation of advanced glycation end-products associated with diabetic nephropathy, as well as DMC's capacity to inhibit the migration and proliferation of vascular smooth muscle cells following balloon angioplasty are also addressed. This review collates the available literature regarding the therapeutic possibilities of DMC in noncancerous conditions.

Nanoliposomal Encapsulation Enhances In Vivo Anti-Tumor Activity of Niclosamide against Melanoma.

BACKGROUND: Niclosamide is an FDA-approved and old anti-helminthic drug used to treat parasitic infections. Recent studies have shown that niclosamide has broad anti-tumor effects relevant to the treatment of cancer. However, this drug has a low aqueous solubility hindering its systemic use. Herein, we report the preparation and characterization of niclosamide nanoliposomes and their in vivo anti-tumor effects. METHODS: Nanoliposomes were prepared using thin-film method and the drug was encapsulated with a remote loading method. The nanoliposomes were investigated by the observation of morphology, analysis of particle size and zeta potential. Additionally, qualitative and quantitative analyses were performed using HPLC. We assessed the in vitro cytotoxicity of the nanoliposomal niclosamide on B16F10 melanoma cells. Inhibition of tumor growth was investigated in C57BL/6 mice bearing B16F0 melanoma cancer. RESULTS: Analytical results indicated that the nanoliposomal system is a homogeneous and stable colloidal dispersion of niclosamide particles. Atomic force microscopy images and particle size analysis revealed that all niclosamide particles had a spherical shape with a diameter of approximately 108nm. According to in vitro and in vivo studies, nanoliposomal niclosamide exhibited a better anti-tumor activity against B16F10 melanoma tumor compared with free niclosamide. CONCLUSION: Nanoliposomal encapsulation enhanced the aqueous solubility of niclosamide and improved its anti-tumor properties.

Liposomal formulation of Galbanic acid improved therapeutic efficacy of pegylated liposomal Doxorubicin in mouse colon carcinoma.

Galbanic acid (Gba), a sesquiterpene coumarin, with strong antiangiogenic activity could serve as an excellent anti-cancer agent. However, Gba is a poor water-solube which hampered its clinical application. In this study, a pegylated liposomal Gba (PLGba) with HSPC/Cholesterol/mPEG2000-DSPE (56.2, 38.3, 5.3% molar ratio) was developed by the thin film hydration plus extrusion and calcium acetate gradient remote loading method, to address the issue of poor Gba solubility. Moreover, an integrin-targeting ligand (RGD peptide, cyclo[Arg-Gly-Asp-D-Tyr-Cys]) was post-inserted into liposomes in order to increase Gba cell delivery. Using fluorescently-labeled model liposomes, it was found that the targeting could improve the integrin-mediated cellular uptake of the liposomes in vitro in human umbilical vein endothelial cells (HUVECs), and in vivo as evidenced by chicken chorioallantoic membrane angiogenesis (CAM) model. It also could enrich the liposome accumulation in C26 tumor. Interestingly, co-treatment with PLGba and pegylated liposomal doxorubicin (PLD, also known as Doxil®) had a synergistic and antagonistic antiproliferative effect on the C26 tumor cell line and the normal HUVEC, respectively. In C26 tumor bearing BALB/c mice, the PLGba and PLD combinatorial therapy improved the antitumor efficacy of the treatment as compared to those of single agents. This results have clear implications for cancer therapy.

MPL nano-liposomal vaccine containing P5 HER2/neu-derived peptide pulsed PADRE as an effective vaccine in a mice TUBO model of breast cancer.

Liposomal peptide-based vaccines can potentially suppress cancer cells proliferation in the host. To enhance the effectiveness of vaccination against cancer, additional strategies should also be employed. One strategy to promote peptide-based vaccine efficacy and induce powerful immune responses, is simultaneous activation of CD4+ and CD8+ T cells. To address this problem, we tested the efficacy of a nano-liposomal vaccine containing P5 peptide, a cytotoxic T lymphocytes (CTL) specific peptide derivative of rat HER2/neu protein, Pan HLA-DR (PADRE) peptide, a universal CD4+ T helper cell epitope and monophosphoryl lipid A (MPL) a toll-like receptor 4 ligand. We observed potent CD8+ T cell immune responses in TUBO mice vaccinated with liposomal P5 peptide in combination with PADRE and MPL. Also, this formulation remarkably improved anti-tumor effects against cells overexpressing HER2 in BALB/c mice compared to liposomal vaccine containing P5 only. Furthermore, we found that vaccination with Lip-P5- Integrated PADRE-MPL formulation significantly induced IFN-γ production, increased CD8+ T cells numbers and enhanced survival compared to other groups of treated mice. In conclusion, our study indicated that Lip-P5-Integrated PADRE-MPL, after further confirmatory investigations, could be employed as a promising vaccine to generate potent CTL anti-tumor immune responses that could be beneficial to treatment of HER2+ breast cancer.

Trehalose administration attenuates atherosclerosis in rabbits fed a high-fat diet.

Disruption of macrophage autophagy is a major contributor to macrophage dysfunction and subsequent inflammation leading to atherosclerosis. Trehalose is a natural disaccharide that is able to induce macrophage autophagy-lysosomal biogenesis and reduce inflammation. Here, we studied the efficacy of intravenous trehalose administration in reducing atherosclerotic plaque burden in high-cholesterol-fed rabbits. Adult male New Zealand white Rabbits were fed with a high-fat diet containing 1% cholesterol for 8 weeks followed by a cholesterol-free diet for the next 4 weeks. In the latter 4-week phase of the cholesterol-free diet, one group received intravenous trehalose solution at a dose of 350 mg/kg, three times per week. In the control group, an equivalent volume of PBS (3 mL) was administered with the same protocol. At the end of the 12th week of the study, all rabbits were anesthetized and aortic arch sections were collected followed by hematoxylin and eosin staining and assessment of plaque grading. Fasting serum lipids were also measured using routine enzymatic methods. At the end of the 12th week, there were no significant differences in the body weight and blood lipids between the control- and trehalose-treated groups. Intravenous trehalose administration significantly attenuated atherosclerotic plaque development as revealed by reduced plaque grading ( P = 0.048) and intima/media thickness ratio ( P = 0.017). Intimal thickening was also found to be reduced in the trehalose versus control group, though this reduction did not reach statistical significance. The present study provided evidence as to the efficacy of short-term intravenous trehalose administration in regressing atherosclerotic plaque in high-fat-fed rabbits.

Demethoxycurcumin: A naturally occurring curcumin analogue with antitumor properties.

The eradication of cancer in a patient remains an elusive challenge despite advances in early detection and diagnosis, chemo- and immunotherapy, pinpoint radiation treatments, and expert surgical intervention. Although significant gains have been made in our understanding of cancer cell biology, a definite cure for most cancers does not exist at present. Thus, it is not surprising that the research and medical communities continue to explore the importance and therapeutic potential of natural products in their multimodality cancer treatment approach. Curcuminoids found in turmeric are one such class of natural products that have been extensively investigated for their potential to halt the progression of cancer cell proliferation and, more important, to stop metastasis from occurring. In this review, we examine one curcuminoid (demethoxycurcumin [DMC]) largely because of its increased stability and better aqueous solubility at physiological pH, unlike the more well-known curcuminoid (curcumin), which is largely unabsorbed after oral ingestion. The present review will focus on the signaling pathways that DMC utilizes to modulate the growth, invasion, and metastasis of cancer cells in an effort to provide enhanced mechanistic insight into DMC's action as it pertains to brain, ovarian, breast, lung, skin, and prostate cancer. Additionally, this review will attempt to provide an overview of DMC's mechanism of action by modulating apoptosis, cell cycle, angiogenesis, metastasis, and chemosensitivity. Lastly, it is hoped that increased understanding will be gained concerning DMC's interactive role with microRNA-551a, 5' adenosine monophosphate-activated protein kinase, nuclear factor-κB, Wnt inhibitory factor-1, and heat shock protein 70 to affect the progression of cancer.

One Molecule, Many Targets and Numerous Effects: The Pleiotropy of Curcumin Lies in its Chemical Structure.

Curcumin quite possibly represents one of the most diverse therapeutic agents yet isolated from natural sources. Therapeutic benefits of this extraordinary natural compound have been demonstrated during treatment of a variety of diseases, including cancer, inflammatory processes, immunological disorders, Diabetes, and oxidative stress often associated with hyperlipidemia. Due to its unique molecular chemical structure and functional groups, curcumin may bind with and subsequently either inhibit or activate a variety of endogenous biomolecules, including enzymes, receptors, signaling molecules, metals, transcription factors, and even certain proteins located in cell membranes. In fact, curcumin exerts pharmacologically useful effects through non-covalent interactions with biomolecules. With so many varied biological targets, curcumin (a polyphenol) elicits numerous pleiotropic effects, which is therapeutically advantageous owing to the fact that many pathological disease states involve more than one signaling pathway, receptor, protein/enzyme, or gene. In this paper, we will discuss the underlying mechanisms responsible for the chemical interaction of curcumin with selected classes of biomolecules, rather than attempt to provide an exhaustive list of each and every biomolecule with which curcumin may chemically interact.