Soluble Tumor Necrosis Factor-related Apoptosis-inducing Ligand Research Articles

Heparan sulfate promotes TRAIL-induced tumor cell apoptosis.

TRAIL (TNF-related apoptosis-inducing ligand) is a potent inducer of tumor cell apoptosis through TRAIL receptors. While it has been previously pursued as a potential anti-tumor therapy, the enthusiasm subsided due to unsuccessful clinical trials and the fact that many tumors are resistant to TRAIL. In this report, we identified heparan sulfate (HS) as an important regulator of TRAIL-induced apoptosis. TRAIL binds HS with high affinity (KD = 73 nM) and HS induces TRAIL to form higher-order oligomers. The HS-binding site of TRAIL is located at the N-terminus of soluble TRAIL, which includes three basic residues. Binding to cell surface HS plays an essential role in promoting the apoptotic activity of TRAIL in both breast cancer and myeloma cells, and this promoting effect can be blocked by heparin, which is commonly administered to cancer patients. We also quantified HS content in several lines of myeloma cells and found that the cell line showing the most resistance to TRAIL has the least expression of HS, which suggests that HS expression in tumor cells could play a role in regulating sensitivity towards TRAIL. We also discovered that death receptor 5 (DR5), TRAIL, and HS can form a ternary complex and that cell surface HS plays an active role in promoting TRAIL-induced cellular internalization of DR5. Combined, our study suggests that TRAIL-HS interactions could play multiple roles in regulating the apoptotic potency of TRAIL and might be an important point of consideration when designing future TRAIL-based anti-tumor therapy.

Human Soluble TRAIL Secreted by Modified Lactococcus lactis Bacteria Promotes Tumor Growth in the Orthotopic Mouse Model of Colorectal Cancer.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis of sensitive cancer cells, including colorectal cancer (CRC). Due to its short biological half-life after intravenous administration and related clinical ineffectiveness, novel formulations of TRAIL need to be developed. Here we propose Lactococcus lactis bacteria as a vehicle for local delivery of human soluble TRAIL (hsTRAIL) in CRC. The use of common probiotics targeting guts as carriers for TRAIL could ensure its sustained release at the tumor site and extend the duration of its activity. We have already engineered hsTRAIL-secreting L.lactis bacteria and showed their effectiveness in elimination of human CRC cells in vitro and in vivo in a mouse subcutaneous model. Here, L.lactis(hsTRAIL+) were administered by gastric gavage to SCID mice with orthotopically developed HCT116 tumor in cecum, in monotherapy or in combination with metformin (MetF), already shown to enhance the hsTRAIL anti-tumor activity in subcutaneous CRC model. Oral administration of L.lactis(hsTRAIL+) resulted in significant progression of HCT116 tumors and shortening of the colon crypts. Secretion of hsTRAIL in the colon was accompanied by infiltration of the primary tumor with M2-macrophages, while MetF promoted transient colonization of the gut by L.lactis. Our study indicates that L.lactis bacteria after oral administration enable delivery of biologically active hsTRAIL to colon, however its potential therapeutic effect in CRC treatment is abolished by its pro-tumorigenic signalling, leading to the recruitment of M2-macrophages and tumor growth promotion.

Oxaliplatin Enhances the Apoptotic Effect of Mesenchymal Stem Cells, Delivering Soluble TRAIL in Chemoresistant Colorectal Cancer.

A key problem in colorectal cancer (CRC) is the development of resistance to current therapies due to the presence of cancer stem cells (CSC), which leads to poor prognosis. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a protein that activates apoptosis in cancer cells through union with TRAIL death receptors. Cell therapies as delivery systems can produce soluble TRAIL (sTRAIL) and full-length TRAIL (flTRAIL), showing a high capacity to produce apoptosis in vitro and in vivo assays. However, the apoptotic activity of TRAIL as monotherapy had limitations, so it is important to explore other ways to enhance susceptibility to TRAIL. This study evaluated the cytotoxic and proapoptotic activity of soluble TRAIL overexpressed by mesenchymal stem cells (MSC) in an oxaliplatin-resistant CRC cell line. Bone marrow-MSC were lentiviral transduced for soluble TRAIL expression. DR5 death receptor expression was determined in Caco-2 and CMT-93 CRC cell lines. Sensitivity to first-line chemotherapies and recombinant TRAIL was evaluated by half-maximal inhibitory concentrations. Cytotoxic and proapoptotic activity of soluble TRAIL-MSC alone and combined with chemotherapy pre-treatment was evaluated using co-cultures. Caco-2 and CMT-93 cell lines expressed 59.08 ± 5.071 and 51.65 ± 11.99 of DR5 receptor and had IC50 of 534.15 ng/mL and 581.34 ng/mL for recombinant murine TRAIL (rmTRAIL), respectively. This finding was classified as moderate resistance to TRAIL. The Caco-2 cell line showed resistance to oxaliplatin and irinotecan. MSC successfully overexpressed soluble TRAIL and induced cancer cell death at a 1:6 ratio in co-culture. Oxaliplatin pre-treatment in the Caco-2 cell line increased the cell death percentage (50%) and apoptosis by sTRAIL. This finding was statistically different from the negative control (p < 0.05), and activity was even higher with the oxaliplatin-flTRAIL combination. Thus, oxaliplatin increases apoptotic activity induced by soluble TRAIL in a chemoresistant CRC cell line.

Dose-related immunomodulatory effects of recombinant TRAIL in the tumor immune microenvironment

BackgroundIn addition to specifically inducing tumor cell apoptosis, recombinant tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) has also been reported to influence the cancer immune microenvironment; however, its underlying effects and mechanisms remain unclear. Investigating the immunomodulatory effects and mechanisms of recombinant TRAIL in the tumor microenvironment (TME) may provide an important perspective and facilitate the exploration of novel TRAIL strategies for tumor therapy.MethodsImmunocompetent mice with different tumors were treated with three doses of recombinant TRAIL, and then the tumors were collected for immunological detection and mechanistic investigation. Methodological approaches include flow cytometry analysis and single-cell sequencing.ResultsIn an immunocompetent mouse model, recombinant soluble mouse TRAIL (smTRAIL) had dose-related immunomodulatory effects. The optimal dose of smTRAIL (2 mg/kg) activated innate immune cells and CD8+ T cells, whereas higher doses of smTRAIL (8 mg/kg) promoted the formation of a tumor-promoting immune microenvironment to counteract the apoptotic effects on tumor cells. The higher doses of smTRAIL treatment promoted M2-like macrophage recruitment and polarization and increased the production of protumor inflammatory cytokines, such as IL-10, which deepened the suppression of natural killer (NK) cells and CD8+ T cells in the tumor microenvironment. By constructing an HU-HSC-NPG.GM3 humanized immune system mouse model, we further verified the immunomodulatory effects induced by recombinant soluble human TRAIL (shTRAIL) and found that combinational administration of shTRAIL and trabectedin, a macrophage-targeting drug, could remodel the tumor immune microenvironment, further enhance antitumor immunity, and strikingly improve antitumor effects.ConclusionOur results highlight the immunomodulatory role of recombinant TRAIL and suggest promising therapeutic strategies for clinical application.Graphical

Abstract 2739: Genetic modification of mesothelial cells with full length membrane-bound TRAIL for ovarian cancer treatment

Abstract Mesothelial cells lining the peritoneum play an important role in epithelial ovarian cancer (EOC) locoregional spreading by promoting cancer cell proliferation, adhesion, and invasion into the peritoneal wall and organs. Peritoneal dissemination represents a critical first step in EOC progression, and we posit that genetic modification of mesothelial cells with full length membrane-bound TRAIL is a practical approach to intervention and will provide local control of EOC progression. Here, we stably overexpressed full length tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) with a lentiviral vector in the immortalized mesothelial cell line, MeT5A. Overexpression of TRAIL on the cell surface of MeT5A was confirmed by flow cytometry, and no obvious changes in proliferation or morphology were observed when MeT5A/TRAIL cells were grown in culture. In co-culture experiments, however, MeT5A/TRAIL cells induced apoptosis of surrounding cancer cells and continued proliferating until the culture surface was confluent with mesothelial cells alone. Interestingly, MeT5A/TRAIL not only induced cell death of TRAIL-sensitive cancer cells, such as OVCAR3 and H460, but it also induced significant apoptosis of cancer cells previously deemed resistant to soluble TRAIL, such as A2780, and OVCAR8. This finding suggests that full length TRAIL (amino acid 1-281) expressed on the cell surface is capable of activating death receptor-mediated apoptotic pathways that are not reactive to the soluble form of TRAIL (amino acid 114-281), which was previously developed as a cancer therapeutic and thoroughly evaluated in animal models and clinical trials. When co-cultured with MeT5A/TRAIL, primary ovarian cancer cells from patients also underwent apoptosis as detected by flow cytometry and the upregulation of cleaved caspase-3, caspase-8, caspase-9, PARP, and Bid on Western blots. Next, we assessed the anticancer potential of mesothelial cells expressing membrane-bound TRAIL in a NSG xenograft mouse model of ovarian cancer. Intraperitoneal inoculation of MeT5A/TRAIL cells significantly reduced overall cancer burden in mice where OVCAR3, A2780, and OVCAR8 cancer cells were pre-established. Intraperitoneal gene delivery of TRAIL to resident peritoneal mesothelial cells utilizing a conditionally replicative adenovirus vector also prolonged survival of NSG mice bearing A2780 xenografts. Our data suggest that genetic modification of mesothelial cells with full length membrane-bound TRAIL is feasible and has therapeutic potential for disrupting EOC progression. Citation Format: Er Yue, Tonya Walser, Tamara Mirzapoiazova, Ravi Salgia, Edward W. Wang. Genetic modification of mesothelial cells with full length membrane-bound TRAIL for ovarian cancer treatment [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2739.

Impact of soluble tumor necrosis factor-related apoptosis-inducing ligand released by engineered adipose mesenchymal stromal cells on white blood cells

Background aimsThe proapoptotic protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is physiologically expressed by immune cells and performs regulatory functions in infections, autoimmune diseases and cancer, where it acts as a tumor suppressor. Adipose-derived mesenchymal stromal cells (AD-MSCs) also may play immunomodulatory roles in both primary and acquired immune responses. We have previously demonstrated the efficacy of an anticancer gene therapy based on AD-MSC engineered to secrete a soluble TRAIL variant (sTRAIL) against pancreatic cancer. However, the impact of AD-MSC sTRAIL on leukocyte subsets has been not yet considered also to predict a possible immunotoxicity profile in the clinical translation of this cell-based anticancer strategy. MethodsMonocytes, polymorphonuclear cells and T lymphocytes were freshly isolated from the peripheral blood of healthy donors. Immunophenotype and functional (DR4 and DR5) and decoy (DcR1 and DcR2) TRAIL receptors were tested by flow cytometry. The viability of white blood cells treated with sTRAIL released by gene-modified AD-MSC or co-cultured with AD-MSC sTRAIL was then evaluated by both metabolic assays and flow cytometry. In addition, cytokine profile in co-cultures was analyzed by multiplex enzyme-linked immunosorbent assay. ResultsMonocytes and polymorphonuclear cells showed high positivity for DR5 and DcR2, respectively, whereas T cells revealed negligible expression of all TRAIL receptors. Irrespective of TRAIL receptors’ presence on the cell membrane, white blood cells were refractory to the proapoptotic effect displayed by sTRAIL secreted by gene-modified AD-MSC, and direct cell-to-cell contact with AD-MSC sTRAIL had negligible impact on T-cell and monocyte viability. Cytokine crosstalk involving interleukin 10, tumor necrosis factor alpha, and interferon gamma secreted by T lymphocytes and vascular endothelial growth factor A and interleukin 6 released by AD-MSC was highlighted in T-cell and AD-MSC sTRAIL co-cultures. ConclusionsIn summary, this study demonstrates the immunological safety and thus the clinical feasibility of an anticancer approach based on AD-MSC expressing the proapoptotic molecule sTRAIL.

Tumor necrosis factor-related apoptosis-inducing ligand gene polymorphism and its plasma phenotype in relation to Crohn's disease

Objectives: To investigate the associations of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene polymorphism and plasma soluble TRAIL level (sTRAIL) with Crohn's disease (CD) and to retrospectively analyze the effects of TRAIL gene variants and plasma sTRAIL levels on clinical response to infliximab (IFX). Methods: From January 2012 to January 2021, 312 CD patients [205 males, 107 females, average age (33.9±9.8) years] and 514 age-and gender-matched healthy controls [304 males, 210 females, average age (34.9±9.4) years] were recruited from the Department of Gastroenterology, the Second Affiliated Hospital of Wenzhou Medical University. Among them, 72 patients with active CD who were ineffective or intolerant to traditional drug therapy regularly received IFX (5 mg/kg) treatment. According to the changes in the Harvey-Bradshaw index (HBI) and the Simplified Endoscopic Score for Crohn's Disease (SES-CD) in the 14th week, these patients were classified into response group (a decrease in HBI≥3 or a decrease in SES-CD≥50%) and non-response group. TRAIL (rs1131568) gene polymorphism was analyzed by matrix-assisted laser desorption/ionization time of flight mass spectrometry technique. The plasma sTRAIL level was examined by enzyme-linked immunosorbent assay (ELISA). Based on the Montreal CD classification criteria, all CD patients were divided into different subgroups. Finally, a comprehensive analysis was performed to investigate the relationship between TRAIL (rs1131568) gene polymorphism, the plasma sTRAIL level and the risk of CD, the clinicopathological characteristics of CD patients, and the clinical response to IFX. Results: The recessive model analysis showed that the homozygous variant genotype (CC) was more prevalent in patients with moderately to severely active CD than in those with mildly active CD (45.34% vs 29.23%, P=0.005). Both variant allele (C) and homozygous variant genotype (CC) in patients with stricturing and penetrating CD were more frequent than those in patients with non-stricturing and non-penetrating CD (65.48% vs 57.53%, P=0.046; 49.21% vs 31.18%, P=0.001). The dominant model analysis showed that variant allele (C) and variant genotype (TC+CC) was higher in CD patients with perianal lesions than in those without perianal lesions (66.83% vs 58.17%, P=0.037; 92.31% vs 78.37%, P=0.002). The average plasma sTRAIL level was higher in CD patients than in healthy controls [(243.04±42.74) ng/L vs (194.16±31.14) ng/L, P<0.001]. Compared with the patients with mildly active CD, the plasma sTRAIL level was increased in those with moderately to severely active CD [263.47(242.09, 281.91) ng/L vs 231.13(211.11, 247.11) ng/L, P<0.001]. The same conclusion was also drawn for the patients with stricturing and penetrating CD in contrast to those with non-stricturing and non-penetrating CD [266.18 (246.68, 289.91) ng/L vs 227.19 (204.57, 249.59) ng/L, P<0.001]. The plasma sTRAIL level was also higher in patients with perianal disease than in those without perianal disease [(261.40±41.51) ng/L vs (233.86±40.41) ng/L, P<0.001]. Multiple linear regression analysis further showed that disease activity (β=22.640, P<0.001) and homozygous variant genotype (CC) (β=16.814, P<0.001) may be positively related to the plasma sTRAIL level in CD patients independently. At the 14th week of IFX treatment, the plasma sTRAIL level in the response group was lower than that in the non-response group [205.98(190.72, 214.56) ng/L vs (238.33±29.38) ng/L, P<0.001]. Compared with week 0, the plasma sTRAIL level was decreased in the response group in the 14th week [(205.98 (190.72, 214.56) ng/L vs (239.89±42.43) ng/L, P<0.001]. Non-conditional logistic regression analysis showed that variant allele (C) and variant genotype (TC+CC) were less frequent in the response group than in the non-response group (53.33% vs 70.83%, P=0.037; 70.00% vs 91.67%, P=0.036). Conclusions: The increased plasma sTRAIL level may be a risk factor for CD. TRAIL (rs1131568) gene variation and the increase of plasma sTRAIL level may be associated with the increased disease activity of CD and may be the risk factors for stenosis, penetration, and perianal lesions in CD patients. In addition, TRAIL (rs1131568) gene variation or the increase of plasma sTRAIL level may be related to no response to IFX treatment in CD patients.

DR5 Up-Regulation Induced by Dichloroacetate Sensitizes Tumor Cells to Lipid Nanoparticles Decorated with TRAIL.

Cancer resistance to treatments is a challenge that researchers constantly seek to overcome. For instance, TNF-related apoptosis-inducing ligand (TRAIL) is a potential good prospect as an anti-cancer therapy, as it attacks tumor cells but not normal cells. However, treatments based in soluble TRAIL provided incomplete clinical results and diverse formulations have been developed to improve its bioactivity. In previous works, we generated a new TRAIL formulation based in its attachment to the surface of unilamellar nanoliposomes (LUV-TRAIL). This formulation greatly increased apoptosis in a wide selection of tumor cell types, albeit a few of them remained resistant. On the other hand, it has been described that a metabolic shift in cancer cells can also alter its sensitivity to other treatments. In this work, we sought to increase the sensitivity of several tumor cell types resistant to LUV-TRAIL by previous exposure to the metabolic drug dichloroacetate (DCA), which forces oxidative phosphorylation. Results showed that DCA + LUV-TRAIL had a synergistic effect on both lung adenocarcinoma A549, colorectal HT29, and breast cancer MCF7 cells. Despite DCA inducing intracellular changes in a cell-type specific way, the increase in cell death by apoptosis was clearly correlated with an increase in death receptor 5 (DR5) surface expression in all cell lines. Therefore, DCA-induced metabolic shift emerges as a suitable option to overcome TRAIL resistance in cancer cells.

Production of Soluble Murine TRAILs in Escherichia coli with Zn2+ Supplementation.

Accumulating evidence has demonstrated the immunomodulatory effects of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) in rheumatoid arthritis and the tumor microenvironment, besides its known capacity of specifically inducing the apoptosis of cancer cells. Mice are common available animal models for studying the roles of TRAIL. However, mice express only a single TRAIL receptor (mTRAILR) with an intracellular death domain, in contrast to the two TRAIL receptors (TRAILR1 and TRAILR2) in humans. Moreover, human TRAIL binds weakly to mTRAILR, whereas mouse TRAIL has a high affinity for human TRAIL-Rs. Therefore, we considered that murine TRAIL would be more suitable than human TRAIL for exploring the immunoregulatory effect of TRAIL in immunocompetent mice or when using mouse cells as the target. To our knowledge, the detailed method for the production of recombinant murine TRAIL has not been reported. In this study, we aimed to design and express two soluble forms of murine TRAIL and verify the properties of the protein. Recombinant murine TRAILs were expressed in Escherichia coli BL21 (DE3, and Nichelating affinity chromatography was used for protein purification. SDS-PAGE, GDS-PAGE and HPLC were applied to analyze the protein structure. The cytotoxicity of our purified murine TRAILs was evaluated in the TRAIL-sensitive human breast cancer ZR-75-30 cells and murine breast cancer 4T1 cells. Finally, validation of the tumor-killing ability of the murine protein in vivo. Two soluble forms of murine TRAILs (mT_N99 and mT_N188) were purified and demonstrated with high purity and trimeric structure. In addition, Zn2+ supplement was essential to produce soluble murine TRAILs in E.coli BL21 (DE3). The two purified soluble mTRAILs showed similar cytotoxicity to cancer cells, moreover, mT_N99 also showed a good anti-tumor effect in vivo and is more suitable for the treatment of murine tumor models. A production approach for recombinant murine TRAIL was determined, which covered the design of shortened forms, expression, purification and characterization.

Generation Natural Killer Cell-Mimic Nanoparticles for Active Targeting of Acute Myeloid Leukemia

Natural killer (NK) cells play a crucial role in recognizing and killing emerging tumor cells. Via an array of activating and inhibitory receptors, NK cells can target and kill abnormal cells, including tumor cells, without prior antigen sensitization. However, fully-established tumors employ numerous mechanisms to inactivate NK cells or hide from them, for example by shedding NK cell-activating ligands, like NK2GD (Chiossone et al., 2018). Here, we describe the engineering of nanoparticles (NPs) functionalized with tumor-recognizing and cytotoxic components of NK cells to address this problem and develop a nanoparticle-based treatment strategy simulating NK cell functionality. Liposomes were synthesized using the thin film hydration method followed by extrusion and functionalized them with the death ligand, TRAIL (tumor necrosis factor-related apoptosis-inducing ligand), immunoglobulin Fc-binding peptide (FCP, replicating the function of NK CD16 receptor) and the therapeutic antibody, anti-CD38 (daratumumab, Panel A) to target acute myeloid leukemia (AML). Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to monitor morphology and size of liposomes. The potential of NK cell-mimic NPs (CD38-NK.NPs) to target and kill AML cells was evaluated on primary AML blasts and a disseminated AML xenograft for which the CD38-positive AML cell line, OCI-AML2 was engrafted into 8-9 week-old female NSG mice. Upon establishment of AML, the mice were injected intraperitoneally (i.p) with 5 doses of either naked liposomes (as vehicle control), soluble TRAIL protein (sTRAIL), LP/TRAIL or CD38-NK.NPs every two days. Tumor burden was monitored by determining the frequency of live human CD45+ cells in the peripheral blood, spleen and bone marrow with flow cytometry. Liposome was chosen as the base of the NP due to its high biocompatibility, biodegradability, cell-like characteristics and capability to penetrate through vessel walls (Pattni, Chupin and Torchilin, 2015). TEM and DLS measurements showed the generated NK.NPs were monodisperse with an average diameter of 145 nm, a size enabling vessel transmigration and avoiding kidney filtration (Gaumet et al., 2008). Immunofluorescent labelling of TRAIL, FCP and antibody verified CD38-NK.NPs functionalization. In vitro, both TRAIL-conjugated liposomes and CD38-NK.NPs were more effective in killing AML cell lines (ML-1, ML-2, Kasumi-1, and OCI-AML2) than sTRAIL, indicating that TRAIL-mediated cytotoxicity can be enhanced by presenting TRAIL in a conformation close to its membrane-bound structure. No significant difference could be detected between LP/TRAIL vs. CD38-NK.NP cytotoxicity in the in vitro assays. On the other hand, CD38-NK.NPs were more effective in killing primary AML blasts than non-targeted, NP-conjugated TRAIL (LP/TRAIL, 13±17% vs 4±15% killing, respectively). Moreover, CD38-NK.NPs showed considerably higher activity relative to the NK cell line, KHYG-1, against CD38-positive AML cell lines. Notably, CD38-NK.NPs showed no significant cytotoxic effect on non-malignant peripheral blood leukocytes. In vivo, NK cell-mimic NPs were more efficient in targeting and eradicating CD38-positive AML cells that either sTRAIL or LP/TRAIL, shown by the reduced percentage of circulating hCD45+ AML cells in treated mice (Panel B). CD38-NK.NPs were also more efficient in inhibiting accumulation of AML cells in the bone and spleen than sTRAIL and LP/TRAIL (Panel B), confirming the ability of CD38-NK.NPs to actively target AML cells expressing the targeted biomarker. Of note, CD38-NK.NPs showed no detectable systemic toxicity or damage to kidneys, liver and pancreas in healthy NSG mice. Overall, we have developed an NK cell-mimic nanoparticle able to actively target AML based on AML surface marker expression without any detectable systematic toxicity. Importantly, due to the modular built of the NK.NPs, they can be functionalized by any therapeutic tumor-targeting antibody via the immunoglobulin-binding peptide (FCP), thus enabling selective targeting tumor cells based on expression of tumor-specific markers and enabling personalized therapy. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Human Umbilical Cord MSC Delivered-Soluble TRAIL Inhibits the Proliferation and Promotes Apoptosis of B-ALL Cell In Vitro and In Vivo.

The TNF-related apoptosis-inducing ligand (TRAIL) could induce apoptosis of leukemic cells, while showed no cytotoxic effect on normal cells. One of the limitations for application of recombinant TRAIL (rhTRAIL) in leukemia treatment is that the serum half-life of this protein is short. Gene delivery is a good strategy to prolong the half-life of TRAIL. In this study, we genetically engineered umbilical cord-MSCs to continuously express and secrete soluble TRAIL (MSC-sTRAIL), to investigate the effects of MSC-sTRAIL on B-cell acute lymphocytic leukemia (B-ALL) cells. In vitro, MSC-sTRAIL significantly inhibited the proliferation of B-ALL cells by suppressing PI3K/AKT and MEK/ERK signaling pathways, and induced apoptosis of B-ALL cells via the caspase cascade-mediated pathway and mitochondrial-mediated pathway. In vivo, MSC-sTRAIL dramatically inhibited B-ALL cell growth. Meanwhile, B-ALL-induced splenic and renal injuries were significantly alleviated after MSC-sTRAIL treatment. Moreover, the serum levels of MSC-secreted sTRAIL were still high in MSC-sTRAIL treated mice, indicating an extended half-life of sTRAIL. Our study suggests that MSC delivered-TRAIL secretion is a potential therapeutic strategy for B-ALL treatment.

Elevated soluble death receptor 5 can predict poor prognosis in patients with acute respiratory distress syndrome

ABSTRACT Background The tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and its receptor, death receptor 5 (DR5), participate in pulmonary cell apoptosis. This study aimed to investigate the clinical value of soluble DR5 and TRAIL for prognosis assessment in acute respiratory distress syndrome (ARDS). Research design and methods Serum and bronchoalveolar lavage fluid (BALF) samples were collected from ARDS patients and controls. Patients were followed-up until death or discharge. Soluble DR5, TRAIL, TNF-α, soluble receptor for advanced glycation end-products (sRAGE), and albumin levels were measured using the Magnetic Luminex or enzyme-linked immunosorbent assays. Data were analyzed according to their distributions and statistical purposes. Results Serum and BALF DR5 levels were elevated in patients with ARDS; TRAIL elevation and reduction was observed in BALF and serum, respectively. Serum DR5 was higher in non-survivors compared to survivors. Serum DR5 was positively correlated with serum TNF-α and critical illness scores and negatively correlated with serum TRAIL. Serum DR5 exhibited potential for predicting mortality in patients with ARDS. Conclusions Serum soluble DR5 elevation, a valuable prognosis predictor in ARDS, may be associated with alveolar epithelial cell apoptosis. Trial Registration http://www.chictr.org.cn/index.aspx.Uniqueidentifier:ChiCTR-DDD-17013370.

Repositioning the Role of Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) on the TRAIL to the Development of Diabetes Mellitus: An Update of Experimental and Clinical Evidence.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a member of the TNF protein superfamily, represents a multifaceted cytokine with unique biological features including both proapoptotic and pro-survival effects in different cell types depending on receptor interactions and local stimuli. Beyond its extensively studied anti-tumor and immunomodulatory properties, a growing body of experimental and clinical evidence over the past two decades suggests a protective role of TRAIL in the development of type 1 (T1DM) and type 2 (T2DM) diabetes mellitus. This evidence can be briefly summarized by the following observations: (i) acceleration and exacerbation of T1DM and T2DM by TRAIL blockade or genetic deficiency in animal models, (ii) prevention and amelioration of T1DM and T2DM with recombinant TRAIL treatment or systemic TRAIL gene delivery in animal models, (iii) significantly reduced circulating soluble TRAIL levels in patients with T1DM and T2DM both at disease onset and in more advanced stages of diabetes-related complications such as cardiovascular disease and diabetic nephropathy, (iv) increase of serum TRAIL levels in diabetic patients after initiation of antidiabetic treatment and metabolic improvement. To explore the underlying mechanisms and provide mechanistic links between TRAIL and diabetes, a number of animal and in vitro studies have reported direct effects of TRAIL on several tissues involved in diabetes pathophysiology such as pancreatic islets, skeletal muscle, adipose tissue, liver, kidney, and immune and vascular cells. Residual controversy remains regarding the effects of TRAIL on adipose tissue homeostasis. Although the existing evidence is encouraging and paves the way for investigating TRAIL-related interventions in diabetic patients with cardiometabolic abnormalities, caution is warranted in the extrapolation of animal and in vitro data to the clinical setting, and further research in humans is imperative in order to uncover all aspects of the TRAIL-diabetes relationship and delineate its therapeutic implications in metabolic disease.

Microglial cathepsin E plays a role in neuroinflammation and amyloid β production in Alzheimer's disease.

Regulation of neuroinflammation and β‐amyloid (Aβ) production are critical factors in the pathogenesis of Alzheimer's disease (AD). Cathepsin E (CatE), an aspartic protease, is widely studied as an inducer of growth arrest and apoptosis in several types of cancer cells. However, the function of CatE in AD is unknown. In this study, we demonstrated that the ablation of CatE in human amyloid precursor protein knock‐in mice, called APPNL−G−F mice, significantly reduced Aβ accumulation, neuroinflammation, and cognitive impairments. Mechanistically, microglial CatE is involved in the secretion of soluble TNF‐related apoptosis‐inducing ligand, which plays an important role in microglia‐mediated NF‐κB‐dependent neuroinflammation and neuronal Aβ production by beta‐site APP cleaving enzyme 1. Furthermore, cannula‐delivered CatE inhibitors improved memory function and reduced Aβ accumulation and neuroinflammation in AD mice. Our findings reveal that CatE as a modulator of microglial activation and neurodegeneration in AD and suggest CatE as a therapeutic target for AD by targeting neuroinflammation and Aβ pathology.

TRAIL Coated Genetically Engineered Immunotherapeutic Nano‐Ghosts Vesicles Target Human Melanoma‐Avoiding the Need for High Effective Therapeutic Concentration of TRAIL

AbstractCancer cell therapy using cytotoxic T lymphocytes (CTL) or mesenchymal stem cells (MSC) possesses hurdles due to the cells, susceptibility to host induced changes. Here, versatile inanimate broadly applicable nanovesicles, termed immunotherapeutic‐nano‐ghosts (iNGs), are armed with inherent surface‐associated targeting and therapeutic capabilities in which the promise and benefits of MSC therapy and T cell immunotherapy are combined into one powerful off‐the‐shelf approach for treating malignant diseases. To mimic the cytotoxic or immunosuppressive functions of T cells, iNG are produced from MSC that were genetically engineered (GE) or metabolically manipulated to express additional membrane‐bound proteins, endowing the NGs derived therefrom with additional surface‐associated functions such as tumor necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL). iNGs from GE‐MSCs (GE‐iNGs) show superior TRAIL retention and induce apoptosis in different cancer cell lines in vitro. In vivo studies on a human melanoma model demonstrate that a systemic, three‐day frequency, administration of GE‐iNGs result in tumor inhibition comparable to a six orders of magnitude higher concentration of soluble TRAIL. The iNGs are therefore a promising nanovesicle platform that can affect tumors in a non‐immunogenic manner while avoiding the need for a highly effective therapeutic concentration.

Embelin downregulated cFLIP in breast cancer cell lines facilitate anti-tumor effect of IL-1\u03b2-stimulated human umbilical cord mesenchymal stem cells

Breast cancer is the leading cause of cancer-related death for women. In breast cancer treatment, targeted therapy would be more effective and less harmful than radiotherapy or systemic chemotherapy. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been shown to induce apoptosis in cancer cells but not in normal cells. Mesenchymal stem cells have shown great therapeutic potential in cancer therapy owing to their ability of homing to tumor sites and secreting many kinds of anti-tumor proteins including TRAIL. In this study, we found that IL-1β-stimulated human umbilical cord-derived mesenchymal stem cells (hUCMSCs) enhance the expression of membrane-bound and soluble TRAIL. Cellular FADD-like IL-1β-converting enzyme inhibitory protein (cFLIP) is an important regulator in TRAIL-mediated apoptosis and relates to TRAIL resistance in cancer cells. Previous studies have shown that embelin, which is extracted from Embelia ribes, can increase the TRAIL sensitivity of cancer cells by reducing cFLIP expression. Here we have demonstrated that cFLIPL is correlated with TRAIL-resistance and that embelin effectively downregulates cFLIPL in breast cancer cells. Moreover, co-culture of IL-1β-stimulated hUCMSCs with embelin-treated breast cancer cells could effectively induce apoptosis in breast cancer cells. The combined effects of embelin and IL-1β-stimulated hUCMSCs may provide a new therapeutic strategy for breast cancer therapy.

TRAIL-R3 Expression on Myeloid Leukemic Blasts Is Related to a Shortened Overall Survival.

Since chemotherapy and transplantation can cure only around 35% of patients with acute myeloid leukemia (AML), there is still need for complementary and targeted treatment modalities. One of them could be the use of TNF-related apoptosis-inducing ligand (TRAIL). TRAIL is expressed by effector T cells and induces apoptosis via the death receptor intrinsic pathway. Activation of this pathway in addition to the mitochondrial pathway (by chemotherapy) has synergistic effects in vitro. In human, 4 membrane bound receptors have been identified: two of them (R1 and R2) contain a functional death domain and are capable of starting the apoptotic cascade, and two others (R3 and R4) lack a functional death domain and function as decoy receptors. Most normal cells express R3 and R4, where many tumor cells express R1 and R2. This makes soluble recombinant TRAIL an attractive candidate for targeted therapy; phase 1 clinical studies for solid tumors are launched. Until now, sparse data on TRAIL sensitivity of myeloid leukemic cells have demonstrated low TRAIL sensitivity. We investigated blood and bone-marrow samples of 113 patients with AML for TRAIL receptor expression by flow-cytometry. In contrast with published data, we found presumably (pro-apoptotic) R1 and R2 expression (mean percentage positive cells 16% and 34%, range 0–79% and 0–97% respectively) versus R3 and R4 expression (mean 9% and 10%, range 0–71% an 0–45%) indicating a TRAIL sensitive profile for myeloid blasts. Surprisingly, the expression of the anti-apoptotic R3 strongly correlated to survival. Expression of > 25% blasts positive for R3 resulted in shortened overall survival (p=0.0051), see figure 1. In multivariate analysis R3 expression remained a significant prognostic factor next to cytogenetics (p=0.03 and p= 0.015 respectively). In vitro studies on 4 myeloid leukemic cell lines confirmed TRAIL sensitivity in cell lines that expressed R1 and R2. Furthermore, simultaneous expression of R3 clearly reduced the amount of apoptosis, suggesting that TRAIL effects are inhibited by binding to R3. TRAIL induction studies on fresh leukemic samples are currently underway in our laboratory.In conclusion, our data suggest that, in contrast to earlier reports, there might be a role for TRAIL in apoptosis induction of AML blasts. R3 expression is a strong predictor for overall survival and modulation of R3 might yield additional new therapeutic options for AML patients. [Display omitted]

The Anti-Tumor Effect of Lactococcus lactis Bacteria-Secreting Human Soluble TRAIL Can Be Enhanced by Metformin Both In Vitro and In Vivo in a Mouse Model of Human Colorectal Cancer.

Simple SummaryColorectal cancer (CRC) is a major cause of morbidity and mortality in Europe, and accounts for over 10% of all cancer-related deaths worldwide. These indicate an urgent need for novel therapeutic options in CRC. Here, we analysed if genetically modified non-pathogenic Lactococcus lactis bacteria can be used for local delivery of human recombinant Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) and induction of tumor cells death in vitro and in vivo in CRC mouse model. We showed that modified L. lactis bacteria were able to secrete biologically active human soluble TRAIL (L. lactis(hsTRAIL+)), which selectively eliminated human CRC cells in vitro, and was further strengthened by metformin (MetF). Our results from in vitro studies were confirmed in vivo using subcutaneous NOD-SCID mouse model of human CRC. The data showed a significant reduction of the tumor growth by intratumor injection of L. lactis(hsTRAIL+) bacteria producing hsTRAIL. This effect could be further enhanced by oral administration of MetF.Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) induces apoptosis of many cancer cells, including CRC cells, being non-harmful for normal ones. However, recombinant form of human TRAIL failed in clinical trial when administered intravenously. To assess the importance of TRAIL in CRC patients, new form of TRAIL delivery would be required. Here we used genetically modified, non-pathogenic Lactococcus lactis bacteria as a vehicle for local delivery of human soluble TRAIL (hsTRAIL) in CRC. Operating under the Nisin Controlled Gene Expression System (NICE), the modified bacteria (L. lactis(hsTRAIL+)) were able to induce cell death of HCT116 and SW480 human cancer cells and reduce the growth of HCT116-tumor spheres in vitro. This effect was cancer cell specific as the cells of normal colon epithelium (FHC cells) were not affected by hsTRAIL-producing bacteria. Metformin (MetF), 5-fluorouracil (5-FU) and irinotecan (CPT-11) enhanced the anti-tumor actions of hsTRAIL in vitro. In the NOD-SCID mouse model, treatment of subcutaneous HCT116-tumors with L. lactis(hsTRAIL+) bacteria given intratumorally, significantly reduced the tumor growth. This anti-tumor activity of hsTRAIL in vivo was further enhanced by oral administration of MetF. These findings indicate that L. lactis bacteria could be suitable for local delivery of biologically active human proteins. At the same time, we documented that anti-tumor activity of hsTRAIL in experimental therapy of CRC can be further enhanced by MetF given orally, opening a venue for alternative CRC-treatment strategies.

TRAIL-Armed ER Nanosomes Induce Drastically Enhanced Apoptosis in Resistant Tumor in Combination with the Antagonist of IAPs (AZD5582).

Although mesenchymal stem cells (MSCs) can be engineered to deliver the TNF-related apoptosis-inducing ligand (TRAIL) as an effective anticancer therapy, the clinical application is hampered by the costly manufacturing of therapeutic MSCs. Therefore, it is needed to find an alternative cell-free therapy. In this study, TRAIL-armed endoplasmic reticulum (ER)-derived nanosomes (ERN-T) are successfully prepared with an average size of 70.6nm in diameter from TRAIL transduced MSCs. It is demonstrated that the ERN-T is significantly more efficient for cancer cell killing than the soluble recombinant TRAIL (rTRAIL). AZD5582 is an antagonist of the inhibitors of apoptosis proteins (IAPs), and its combination with ERN-T induces strikingly enhanced apoptosis in cancerous but not normal cells. AZD5582 sensitizes resistant cancer cells to TRAIL through concomitant downregulation of IAP members like XIAP and the Bcl2 family member Mcl-1. Intravenously infused ERN-Ts accumulate in tumors for over 48 h indicating good tumor tropism and retention. The combination of ERN-T and AZD5582 drastically promotes therapeutic efficacy comparing with the cotreatment by rTRAIL and AZD5582 in a subcutaneous MDA-MB-231 xenograft tumor model. The data thus demonstrate that ERN-T can be a novel cell-free alternative to TRAIL-expressing MSC-based anticancer therapy and its efficacy can be drastically enhanced through combination with AZD5582.

A self-sustained nanoplatform reverses TRAIL-resistance of pancreatic cancer through coactivating of exogenous and endogenous apoptotic pathway

Since the 5-year survival rate of pancreatic cancer is only 10.0%, new therapies are urgently needed. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) induces apoptosis specifically on tumor cells, nevertheless its clinical application was seriously restricted by resistance and short in vivo half-life. Herein, a novel multifunctional R6ST protein equipped with cell penetrating peptides R6, intrinsic apoptosis inducing tetrapeptide AVPI and soluble TRAIL was designed and constructed. Then, it was recruited to prepare self-sustained nanoplatform (SSN) to reverse TRAIL-resistance of pancreatic cancer through simultaneously promoting extrinsic and intrinsic apoptotic pathway, as well to elongate circulation time. Once administrated, high tumor accumulation and cellular uptake of SSN were achieved through prolonged circulation time, targeting ability of soluble TRAIL to death receptors and positive-charged R6, and further enhanced through reversed upregulation of death receptors on TRAIL-resistant tumor cells by the cumulated artesunate released in cytoplasm as a positive feedback loop. Furthermore, this loop simultaneously promoted extrinsic apoptosis of TRAIL fragment via the upregulated death receptors on TRAIL-resistant pancreatic cancer cells and intrinsic apoptosis of AVPI tetrapeptide via the efficient accumulation and uptake of R6ST on SSN. Hence, SSN exhibited synergistic antitumor effect and provided a new strategy for TRAIL-resistant pancreatic cancer therapy.