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

Soluble TRAIL in normal pregnancy and acute pyelonephritis: a potential explanation for the susceptibility of pregnant women to microbial products and infection

Objective: Pregnancy is characterized by activation of the innate immune response demonstrated by phenotypic and metabolic changes in granulocytes and monocytes. This state of activation has been implicated in the pathophysiology of multiorgan dysfunction of pregnant women with acute viral or bacterial infection. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is one of the mediators responsible for neutrophil apoptosis. Gene deletion of TRAIL results in delayed neutrophil apoptosis and resolution of inflammation after the administration of bacterial endotoxin. The aim of this study was to determine whether maternal plasma concentrations of the soluble form of TRAIL (sTRAIL) differ in women with uncomplicated pregnancy and those with acute pyelonephritis.Method: A cross-sectional study was conducted to include women in the following groups: (1) non-pregnant (n = 23); (2) uncomplicated pregnancies (n = 93) and (3) pregnancies with acute pyelonephritis (n = 23). Plasma concentrations of sTRAIL were determined by enzyme-linked immunoassay.Results: (1) Women with uncomplicated pregnancies had a lower mean plasma sTRAIL concentration (pg/mL) than non-pregnant women (31.5 ± 10.1 versus 53.3 ± 12.5; p < 0.001); (2) plasma sTRAIL concentrations did not change as a function of gestational age (Pearson correlation = −0.1; p = 0.4); (3) the mean plasma sTRAIL concentration (pg/mL) was significantly lower in pregnant women with acute pyelonephritis than in those with uncomplicated pregnancies (20.5 ± 6.6 versus 31.5 ± 10.1; p < 0.001) and (4) among patients with acute pyelonephritis, patients with bacteremia had a significantly lower mean plasma concentration of sTRAIL (pg/mL) than those without bacteremia (15.1 ± 4.8 versus 24.7 ± 4.6; p < 0.001).Conclusion: Women with uncomplicated pregnancies are associated with a significantly lower mean maternal plasma concentration of sTRAIL than that observed in non-pregnant women. Moreover, a further decrease in plasma sTRAIL concentration was observed in pregnant women with acute pyelonephritis, and this could account, at least in part, for the exaggerated intravascular inflammatory response previously reported in pyelonephritis during pregnancy.

TRAIL-Based Therapeutic Approaches for the Treatment of Pediatric Malignancies

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a pro-apoptotic ligand that has shown the exquisite ability to trigger extrinsic apoptosis in various types of cancer cells without significant toxicity toward normal cells, when compared to other pro-apoptotic ligands such as tumor necrosis factor (TNF) α or Fas ligand. Consequently, TRAIL-based therapies aim to trigger apoptosis in cancer cells by providing the soluble TRAIL or monoclonal antibodies targeting the death receptors TRAIL-R1 or TRAIL-R2. In this review, we start by highlighting the relevance of the tumor microenvironment in tumor development and elimination. We then address conventional and targeted therapeutic approaches for cancer treatment, highlighting the mechanisms involved or targeted. We describe the extrinsic and intrinsic pro-apoptotic pathways of TRAIL, together with the evidences for its pro-survival signaling, and with the relevance of these pathways in therapy. Possible mechanisms of resistance to TRAIL-induced apoptosis are highlighted (i.e. c-FLIP, Bcl-2, IAPs, p53, NF-κ B) and the rationale for the combined administration of TRAIL with drugs targeting these mechanisms is provided. Preclinical data are reported and show encouraging evidences for TRAIL consideration in pediatric malignancies (i.e., leukemia, lymphomas, neuroblastoma, osteosarcoma, medulloblastoma). Clinical trials of TRAIL-based therapies on the overall population are in phase I or II, and we put particular focus on the pediatric population, on which only few trials have been conducted or are ongoing. Finally, we consider emerging cellular therapies based on TRAIL, such as TRAIL-engineered mesenchymal stem cells or 'inflammatory' dendritic cells.

Down regulation of TRAIL and FasL on NK cells by Cyclosporin A in renal transplantation patients

TNF-related apoptosis-inducing ligand (TRAIL) and FasL can participate in cell mediated cytotoxicity via their death domain-mediated apoptotic signaling in the host-versus-graft disease occurred after renal transplantation. However, the effect of Cyclosporin A (CsA) commonly used as a drug to prevent and to treat renal transplant rejection, on these molecules have not been fully determined. In the present study, we found that with CsA administration, the expression of TRAIL and FasL predominantly on NK cells from renal transplantation patients was increased at day 5 after operation and went down to normal level on day 13. While, the levels of soluble TRAIL (sTRAIL) and sFasL in the serum increased within 25 days and went down to normal level three month later. In addition, we showed that a remarkable increase of TRAIL and FasL expression both on the surface of activated lymphocytes especially on NK cells and in the supernatants generated from mixed lymphocytes culture (MLC). Furthermore, the enhancement of these two molecules was greatly decreased by adding 500ng/mL CsA at the beginning of MLC. We conclude that CsA may inhibit the transplant rejection partially by down-regulating the expression of TRAIL and FasL on NK cells.

Levels of TNF-Related Apoptosis-Inducing Ligand (TRAIL) Show a Long-term Stability in the Breast Milk of Mothers of Preterm Infants

The immune modulator TNF-related apoptosis-inducing ligand (TRAIL) has been found at extremely high levels in human milk of women with normal gestation at day 5 after delivery. To investigate the presence and the levels of soluble TRAIL in human milk of women with preterm delivery at different time points post-partum (32, 34, and 36 weeks from conception). The levels of soluble TRAIL were analyzed by ELISA in the breast milk of a group of 25 women with preterm delivery at different gestational ages. Soluble TRAIL was present at high levels in human milk since early post-conceptional ages (32 weeks). No significant differences in TRAIL levels were noticed with respect to different gestational ages, or with respect to time of collection when comparing, in a selected group of patients, samples obtained between 15 and 26 days with those obtained 27 and 40 days after birth. Due to the key immunoregulatory role of human soluble TRAIL, the presence of high levels of TRAIL in the milk of women with preterm delivery and its maintenance at high levels up to 72 days after birth support the importance of breastfeeding the preterm newborn.

Prognostic Value of TNF-Related Apoptosis Inducing Ligand (TRAIL) in Acute Coronary Syndrome Patients

BackgroundApoptosis plays an important role in the development of heart failure. The aim of the prospectively designed study was to assess whether the concentration of apoptotic markers apoptosis-stimulating fragment (Fas, CD95/APO-1) and tumor necrosis factor-related apoptosis inducing ligand (TRAIL) can predict prognosis in patients with acute coronary syndromes.MethodsThe concentrations of soluble Fas and TRAIL were determined in 295 patients with acute coronary syndromes. The status of all patients was evaluated at 6 months. The primary goal was a composite end-point of death and hospitalization for heart failure. The secondary end-points were re-MI, death alone and stroke alone.ResultsDuring the median follow-up of 6 months, 26 patients experienced the composite end-point. Using multivariate logistic regression, the concentration of TRAIL was the strongest significant and independent predictor of composite end-point (OR 0.11 (95% CI 0.03–0.45), p = 0.002). Low concentration was associated with poor prognosis of patients. Other significant predictors of composite end-point were serum creatinine (OR 7.7 (95% CI 1.1–54.5, p = 0.041) and complete revascularization (OR 0.19 (95% CI 0.05–0.78, p = 0.02). Independent significant predictors of death in the multivariate analysis were the concentration of TRAIL (OR 0.053 (95% CI 0.004–0.744), p = 0.029), older age (OR 1.20 (95% CI 1.02–1.41, p = 0.026) and serum creatinine (OR 15.1 (95% CI 1.56–145.2), p = 0.0193). Re-MI or stroke could not be predicted by any combination of obtained parameters.ConclusionsLow concentrations of soluble TRAIL represent a strong predictor of a poor prognosis in patients with acute coronary syndrome. The predictive value of TRAIL concentration is independent of age, ejection fraction, index peak troponin level, concentration of BNP or serum creatinine.

Delivery of sTRAIL variants by MSCs in combination with cytotoxic drug treatment leads to p53-independent enhanced antitumor effects

Mesenchymal stem cells (MSCs) are able to infiltrate tumor tissues and thereby effectively deliver gene therapeutic payloads. Here, we engineered murine MSCs (mMSCs) to express a secreted form of the TNF-related apoptosis-inducing ligand (TRAIL), which is a potent inducer of apoptosis in tumor cells, and tested these MSCs, termed MSC.sTRAIL, in combination with conventional chemotherapeutic drug treatment in colon cancer models. When we pretreated human colorectal cancer HCT116 cells with low doses of 5-fluorouracil (5-FU) and added MSC.sTRAIL, we found significantly increased apoptosis as compared with single-agent treatment. Moreover, HCT116 xenografts, which were cotreated with 5-FU and systemically delivered MSC.sTRAIL, went into remission. Noteworthy, this effect was protein 53 (p53) independent and was mediated by TRAIL-receptor 2 (TRAIL-R2) upregulation, demonstrating the applicability of this approach in p53-defective tumors. Consequently, when we generated MSCs that secreted TRAIL-R2-specific variants of soluble TRAIL (sTRAIL), we found that such engineered MSCs, labeled MSC.sTRAILDR5, had enhanced antitumor activity in combination with 5-FU when compared with MSC.sTRAIL. In contrast, TRAIL-resistant pancreatic carcinoma PancTu1 cells responded better to MSC.sTRAILDR4 when the antiapoptotic protein XIAP (X-linked inhibitor of apoptosis protein) was silenced concomitantly. Taken together, our results demonstrate that TRAIL-receptor selective variants can potentially enhance the therapeutic efficacy of MSC-delivered TRAIL as part of individualized and tumor-specific combination treatments.

650: sTRAIL, a prognostic marker for future death from cardiovascular disease, is decreased in maternal plasma of patients with preeclampsia

650 sTRAIL, a prognostic marker for future death from cardiovascular disease, is decreased in maternal plasma of patients with preeclampsia Piya Chaemsaithong, Tinnakorn Chaiworapongsa, Tamara Stampalija, Nandor Gabor Than, Zhong Dong, Lami Yeo, Sonia Hassan, Roberto Romero NICHD/NIH/DHHS, Perinatology Research Branch, Detroit, MI, Wayne State University School of Medicine, Department of Obstetrics and Gynecology, Detroit, MI OBJECTIVE: Women who develop preeclampsia (PE) are at increased risk of cardiovascular disease later in life. Tumor necrosis factor (TNF)-Related Apoptosis-Inducing Ligand (TRAIL), a potent inducer of apoptosis, has anti-atherosclerotic effects on endothelial cells. Patients with acute coronary artery disease have lower serum concentrations of the soluble TRAIL (sTRAIL), with higher C-reactive protein (CRP) concentrations. sTRAIL and CRP confer a risk for future death (Hazard Ratio 0.93 and 2.2, respectively). The aim of this study was to determine if maternal plasma concentrations of sTRAIL and CRP change in pregnancies with preeclampsia. STUDY DESIGN: A cross-sectional study was conducted in the following groups: 1) normal pregnant women (n 93); and 2) women with PE (n 52). Patients with PE were sub-classified into preterm (n 38) and term ( 37 weeks) PE (n 14). Maternal plasma concentrations of sTRAIL and C-reactive protein (CRP) were determined by ELISA. RESULTS: 1) The median plasma concentration of sTRAIL was significantly lower in patients with PE than in normal pregnant women (25.6 pg/mL vs. 29.2 pg/mL; p 0.03); 2) the preterm (but not term) preeclampsia group had a significantly lower median plasma concentration of sTRAIL than the normal pregnancy group (24.8 pg/mL vs. 30.5 pg/mL; p 0.03 and 26.5 pg/mL vs. 26.8 pg/mL; p 0.7, respectively); and 3) the median plasma concentration of CRP was significantly higher in patients with PE (n 32) than in normal pregnant women (n 53) (8 ng/mL vs. 4.1 ng/mL; p 0.001); however, there was no significant correlation between maternal plasma concentrations of sTRAIL and CRP in either PE (p 0.1) or normal pregnancy (p 0.3). CONCLUSION: Preeclampsia was associated with a lower sTRAIL and a higher CRP concentration in maternal plasma. Both proteins may be involved in the mechanisms of predisposing patients with preeclampsia to future cardiovascular disease. 651 Prospective evaluation of circulating angiogenic factors in the prediction of earlyversus late-onset pre-eclampsia Rebecca Jessel, Ann Thomas, Kee-Hak Lim, Samuel Parry, Thomas McElrath Brigham and Women’s Hospital; Harvard Medical School, Department of Obstetrics and Gynecology, Boston, MA, Brigham and Women’s Hospital; Harvard Medical School, Department of Obstetrics and Gynecology; Division of Maternal Fetal Medicine, Boston, MA, Boston MFM; BIDMC; Harvard Medical School, Boston Maternal-Fetal Medicine, Boston, MA, Hospital of the University of Pennsylvania, Division of Maternal-Fetal Medicine, Hospital of the University of Pennsylvania, PA OBJECTIVE: Circulating angiogenic factors play a role in pathogenesis of preeclampsia (PE) but we have previously demonstrated that they have limited predictive capacity if PE is considered a single entity. However, PE is a heterogeneous disease with early ( 34w) and late onest PE possibly representing different entities. We tested the hypothesis that sequential measurement of sFlt-1 and PlGF in a longitudinal cohort of patients can distinguish patients who are more likely to develop and require delivery for early PE. STUDY DESIGN: 2,241 singleton pregnancies were followed prospectively from the initiation of prenatal care at three regional academic centers. Plasma sFlt-1 and PlGF levels were collected prospectively and quantified by immunoassay at approximately 10, 17, and 24 weeks gestation. Patients were followed through delivery. PE was diagnosed by ACOG criteria. Patients with chronic hypertension and diabetes were excluded from this analysis. RESULTS: Median analyte concentrations for early and late and testing characteristics for the prediction of early PE are presented in the table. Twenty patients developed PE before 34 weeks compared to 182 patients with late PE. Incidence of early PE was 1%. PlGF concentrations are significantly lower among early PE patients at all time points and magnitude of increase with gestation was lower than those with late PE. sFlt-1 concentrations and the ratio are significantly different at 26 weeks. However, the testing characteristics do not suggest clinical utility in the prediction of early PE. CONCLUSION: Our results support the suggestion that PE is a heterogeneous disease with early and late PE possibly representing different disease processes. Despite low incidence, the significant differences in analytes in early versus late suggests a more homogenous cohort. However, the analytes, do not appear to be clinically useful in the prediction of early PE.

Small-molecule activation of the TRAIL receptor DR5 in human cancer cells

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) activates apoptosis through the death receptors DR4 and DR5. Because of its superior safety profile and high tumor specificity compared to other TNF family members, recombinant soluble TRAIL and agonistic antibodies against its receptors are actively being developed for clinical cancer therapy. Here, we describe the identification and characterization of the small molecules that directly target DR5 to initiate apoptosis in human cancer cells. The activity was initially discovered through a high-throughput chemical screen for compounds that promote cell death in synergy with a small-molecule mimetic of Smac, the antagonist for inhibitor of apoptosis protein. Structure-activity relationship studies yielded a more potent analog called bioymifi, which can act as a single agent to induce DR5 clustering and aggregation, leading to apoptosis. Thus, this study identified potential lead compounds for the development of small-molecule TRAIL mimics targeting DR5 for cancer therapy.

The trail to deadly membrane rafts

Tumor necrosis factor-related apoptosis inducing ligand(TRAIL) may stimulate death receptors (DR4 and DR5),decoy receptors (DcR1 and DcR2) antagonizing DR4and DR5, and osteoprotegerin, a regulator of osteoclas-togenesis and soluble TRAIL receptor [1]. All fivereceptors are expressed in endothelial cells and partici-pate in the regulation of inflammation, proliferation,differentiation, and apoptosis [1]. Accordingly, TRAILmay stimulate or inhibit apoptosis. TRAIL-induced ap-optosis involves activation of acid sphingomyelinasewith subsequent generation of ceramide and formationof membrane signaling platforms via clustering of mem-brane rafts, outer cell membrane domains assemblingcholesterol and lipids with saturated acyl chains, suchas sphingolipids and glycosphingolipids [2]. Those plat-forms are particularly important for redox signaling, asthey recruit several molecules decisive for O

TRAIL suppresses tumor growth in mice by inducing tumor-infiltrating CD4(+)CD25 (+) Treg apoptosis.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), a promising and novel anticancer cytokine, specifically kills numerous tumor cells by apoptosis. However, some malignancies are resistant to TRAIL treatment in clinical trials, thus limiting its therapeutic potential. In the present study, the TRAIL-resistant murine hepatocellular carcinoma cell line Hepa1-6 was used to elucidate the physiological significance of TRAIL resistance, especially with respect to the immune regulatory function of TRAIL. Hepa1-6 cells were resistant to TRAIL-induced apoptosis in vitro; however, intratumoral injection of recombinant soluble TRAIL inhibited tumor growth and prolonged survival time in tumor-bearing mice. Local TRAIL treatment decreased the number of intratumoral CD4(+)CD25(+)Foxp3(+) regulatory T cells (Tregs) but did not affect CD4(+)CD25(+)Foxp3(+) Tregs in the draining lymph nodes and spleen. Further investigation showed that TRAIL induced apoptosis of tumor-activated CD4(+)CD25(+)Foxp3(+) Tregs, but not of CD4(+)CD25(-) T cells. Moreover, mouse TRAIL receptor DR5 expression was detected on the surface of the tumor-infiltrating CD4(+)CD25(+)Foxp3(+) Tregs, but not on naïve CD4(+)CD25(+)Foxp3(+) Tregs. Interestingly, intratumoral injection of TRAIL not only decreased the number of CD4(+)CD25(+)Foxp3(+) Tregs but also increased the number of tumor-specific CD8(+) CTL and augmented their cytotoxicity to the tumor cells. These data provide the novel evidence for an immune regulatory function of TRAIL and may shed light on the clinical application of TRAIL.

Synergetic toxicity of DATR, a recombinant soluble human TRAIL mutant, in combination with traditional chemotherapeutics in rats

The recombinant soluble human TRAIL mutant (DATR), derived from tumour necrosis factor-related apoptosis-inducing ligand (TRAIL), is a promising agent for cancer therapy. The present study evaluated the synergetic toxicity of DATR in combination with traditional chemotherapeutics, including irinotecan, polyene paclitaxel and oxaliplatin in rats. Rats treated with polyene paclitaxel alone or in combination with DATR showed severe diarrhea, appetite inhibition, increasing sodium (Na+), potassium (Cl−) and glucose (GLU) and serious disorders in the haematological system. Increasing total bilirubin (TBIL) and blood urea nitrogen (BUN) were detected in the rats treated with oxaliplatin alone or in combination with DATR. Furthermore, except that the BUN and Crea of male rats treated with irinotecan in combination with DATR were higher than those of treated with irinotecan, the addition of DATR does not increase the toxicity induced by irinotecan, polyene paclitaxel and oxaliplatin. In conclusion, DATR probably increases kidney lesions of rat with irinotecan, but does not increase the toxicity induced by polyene paclitaxel and oxaliplatin. This indicated that DATR has promising potential in clinical combination therapies. Furthermore, the toxicity induced by DATR on the liver, kidneys and haematological system should be considered carefully if DATR is used in combination with traditional chemotherapeutics.

Induction of non-small cell lung carcinoma apoptosis using soluble RGD-TRAIL by targeting the integrin receptor of tumor cells

The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a promising candidate for cancer therapeutics that exhibits the ability to preferentially induce apoptosis in malignant cells. RGD peptides bind to the integrins, ανβ3 and ανβ5, which are selectively expressed in tumor neovasculature and at the surface of certain tumor cells. To enhance the antitumor effect, an RGD-TRAIL protein, in which TRAIL was fused with the RGD motif-containing cell adhesive sequence, GRGDNP (gly-arg-gly-asp-asn-pro), was constructed and evaluated for bioactivity. The soluble TRAIL and RGD-TRAIL proteins were expressed in Escherichia coli BL21 (DE3) and purified using a non-denaturing method. The antitumor effect of the purified RGD-TRAIL on cell proliferation was evaluated invitro using MTT and wound healing assays and cell apoptosis was assessed by Hoechst 33342 staining and PARP expression analysis. The results revealed that RGD-TRAIL inhibited the proliferation of multiple tumor cell lines (A549, NCI-H1299 and HCC827). Western blot analysis demonstrated that the treatment of tumor cells with RGD-TRAIL activated the apoptotic pathway by the cleavage of PARP, in the same way as wild-type TRAIL (wtTRAIL). These results demonstrate that RGD-TRAIL possesses more potent antitumor effects than wtTRAIL and, therefore, merits further investigation in preclinical and clinical studies.

Soluble TRAIL is elevated in recurrent miscarriage and inhibits the in vitro adhesion and migration of HTR8 trophoblastic cells

What is the potential physiopathological role of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) in recurrent miscarriage (RM), characterized by at least three consecutive pregnancy losses. The levels of serum TRAIL immediately after miscarriage in RM patients are significantly elevated with respect to that in first-trimester normal pregnant women, and recombinant TRAIL inhibits the adhesion and migration of HTR8 trophoblastic cells in vitro. Both TRAIL and its trans-membrane receptors (TRAIL-R1, TRAIL-R2, TRAIL-R3and TRAIL-R4) have been documented in the placenta, but their physiopathological role is incompletely understood. The study populations consisted of RM patients (n = 80) and first-trimester normal pregnant women (n = 80). Blood samples were obtained within 24 h after abortion (RM) or at gestational 12-week (normal pregnant women). As additional controls, third-trimester normal pregnant women (n = 28) were examined before (within 72 h) and after (within 24 h) partum. The concentrations of TRAIL were analysed in serum samples by ELISA. In parallel, the effect of soluble recombinant TRAIL (0.1-1000 ng/ml) was analysed on the survival of primary extravillus trophoblasts (EVTs) and on the survival, proliferation, adhesion and migration of trophoblastic HTR8 cells. The circulating levels of TRAIL in RM women (median: 52.5 pg/ml; mean and SD: 55.5 ± 24.4 pg/ml) were significantly higher with respect to first-trimester normal pregnant women (median: 44.9 pg/ml; mean and SD: 47 ± 15.1 pg/ml) and third-trimester normal pregnant women, as assessed before (median: 45.1 pg/ml; mean and SD: 46 ± 12.4 pg/ml) and after partum (median: 35.4 pg/ml; mean and SD: 38 + 17.5 pg/ml). Both primary EVT and HTR8 cells expressed detectable levels of TRAIL death receptors, but exposure to soluble recombinant TRAIL did not induce cell death of trophoblastic cells. On the other hand, TRAIL dose-dependently inhibited the adhesion of HTR8 cells to decidual endothelial cells (DEC) as well as the migration of HTR8 in transwell assays using either fibronectin or DEC. Although this study suggests that TRAIL might have a pathogenic role in RM by inhibiting both the adhesion and migration capabilities of first trimester trophoblastic cells, there is a possibility that the elevated serum levels of TRAIL in RM are not cause but rather the result of RM. Our current findings together with data of other authors suggest that circulating TRAIL should be further analysed as a potential important biomarker in different physiopathological settings. This study was funded by FIRB projects (RBAP11Z4Z9_002 to Giorgio Zauli and RBAP10447J_002 to Paola Secchiero). The authors have no competing interests to declare.

Relationship between serum levels of tumour necrosis factor‐related apoptosis‐inducing ligand and the survival of Chinese peritoneal dialysis patients

Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) can counteract inflammation and atherosclerosis, both common causes of morbidity in peritoneal dialysis (PD) patients. We examined the relation between serum soluble TRAIL (sTRAIL) levels and the outcome of Chinese PD patients. We studied 116 new PD patients (67 males, age 56.7 ± 13.4 years). Baseline serum sTRAIL level was determined and grouped to tertiles 1 (lowest) to 3 (highest). All patients were followed for 20.9 ± 7.0 months. Patient survival was 83.4%, 74.2% and 100% for tertiles 1 to 3, respectively, at 24 months (P = 0.021). Multivariate Cox regression analysis showed that serum sTRAIL level was an independent predictor of patient survival after adjusting for confounding factors (adjusted hazard ratio 0.962, 95% confidence interval [CI] 0.935-0.991, P = 0.010). A higher baseline serum sTRAIL level was associated with a better survival of PD patients. The detailed mechanism deserves further investigation.

BCR-ABL regulates death receptor expression for TNF-related apoptosis-inducing ligand (TRAIL) in Philadelphia chromosome-positive leukemia

Allogeneic stem cell transplantation (allo-SCT) is a potentially curative therapy for chronic myeloid leukemia and Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia, and the graft-vs-leukemia (GVL) effect can eradicate residual leukemia after allo-SCT. Ph(+) leukemia cells frequently express death-inducing receptors (DR4 and DR5) for tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), which is one of the cytotoxic ligands expressed on cytotoxic T cells and natural killer cells mediating the GVL effect. Here we demonstrate that imatinib specifically downregulated DR4 and DR5 expression in cell lines and clinical samples of Ph(+) leukemia. Second-generation tyrosine kinase inhibitors (dasatinib and nilotinib) and short hairpin RNA against bcr-abl also downregulated DR4 and DR5 expression in Ph(+) leukemia cells, and transfection of bcr-abl into a Ph(-) leukemia cell line induced DR4 and DR5 expression, which was abrogated by imatinib treatment. Accordingly, Ph(+) leukemia cells that had been pretreated with imatinib showed resistance to the pro-apoptotic activity of recombinant human soluble TRAIL. These observations demonstrate that BCR-ABL is critically involved in the leukemia-specific expression of DR4 and DR5 and in the susceptibility of Ph(+) leukemia to TRAIL-mediated anti-leukemic activity, providing new insight into the mechanisms of the tumor-specific cytotoxic activities of TRAIL.

Oncogenic fusion E2A-HLF sensitizes t(17;19)-positive acute lymphoblastic leukemia to TRAIL-mediated apoptosis by upregulating the expression of death receptors

t(17;19)-acute lymphoblastic leukemia (ALL) shows extremely poor prognosis. E2A-HLF derived from t(17;19) blocks apoptosis induced by the intrinsic mitochondrial pathway and has a central role in leukemogenesis and chemoresistance. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is expressed on cytotoxic T cells and natural killer cells and binds with death receptors (DR4/DR5), inducing apoptosis by dual activation of intrinsic and extrinsic pathways, and TRAIL mediates the graft-versus-leukemia (GVL) effect after allogeneic stem cell transplantation (allo-SCT). We found that cell lines and patients' samples of t(17;19)-ALL expressed death receptors for TRAIL, and recombinant soluble TRAIL immediately induced apoptosis into t(17;19)-ALL cell lines. E2A-HLF induced gene expression of DR4/DR5, which was dependent on the DNA-binding and transactivation activities of E2A-HLF through the 5' upstream region of the start site at least in the DR4 gene. Introduction of E2A-HLF into non-t(17;19)-ALL cell line upregulated DR4 and DR5 expression, and sensitized to proapoptotic activity of recombinant soluble TRAIL. Finally, a newly diagnosed t(17;19)-ALL patient underwent allo-SCT immediately after induction of first complete remission, and the patient has survived without relapse for over 3-1/2 years after allo-SCT. These findings suggest that E2A-HLF sensitizes t(17;19)-ALL to the GVL effect by upregulating death receptors for TRAIL.

Correlations of genetic polymorphisms of tumor necrosis factor-related apoptosis-inducing ligand gene and its plasma phenotype with ulcerative colitis

To explore the correlations of genetic polymorphisms in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) gene and the plasma levels of soluble TRAIL (sTRAIL) with ulcerative colitis (UC). From May 2004 to April 2011, a total of 393 UC patients were recruited from Second and First Affiliated Hospitals of Wenzhou Medical College and Second Renmin Hospital of Wenzhou City. During the same period, a total of 1292 healthy controls were recruited from Physical Examination Center at Second Affiliated Hospital of Wenzhou Medical College. After PCR amplification, the genetic polymorphisms in TRAIL (G1525A, G1588A, C1595T) genes were examined by direct sequencing, and the haplotype analysis were also performed in all study subjects. Furthermore, the plasma levels of sTRAIL were determined by enzyme-linked immunosorbent assay (ELISA). The frequencies of variant genotypes in TRAIL (G1525A, G1588A, C1595T) genes were significantly lower in the UC patients than those in the controls (all P < 0.01). Both of variant allele frequencies in TRAIL G1525A and G1588A were significantly decreased in UC patients (40.08% (315/786) vs 54.95% (1420/2584), 49.49% (389/786) vs 55.53% (1435/2584), both P < 0.01). However, the variant allele frequency in TRAIL C1595T gene was not significantly lower in the UC patients (P = 0.133). According to disease severity, the UC patients were divided into mild, intermediate and severe groups. The frequencies of variant allele (T) and genotype (CT + TT) in TRAIL C1595T gene were also significantly higher in the patients with severe UC than those in others (63.50% (127/200) vs 49.15% (288/586), 77.00% (77/100) vs 61.43% (180/293), both P < 0.01). In haplotype analysis, the frequency of GAT haplotype was significantly higher in the UC patients than that in the controls. However, the frequency of AAT haplotype was significantly lower in the UC patients (both P < 0.01). Furthermore, the plasma levels of sTRAIL were significantly higher in the UC patients than those in the controls ((1.05 ± 0.48) vs (0.96 ± 0.90) ng/L, P < 0.01). The genetic polymorphisms of TRAIL (G1525A, G1588A, C1595T) and the plasma levels of sTRAIL are correlated with UC in Chinese patients.

Human Colostrum and Breast Milk Contain High Levels of TNF-Related Apoptosis-Inducing Ligand (TRAIL)

TNF-related apoptosis inducing ligand (TRAIL) is a pleiotropic cytokine, which plays a key role in the immune system as well as in controlling the balance of apoptosis and proliferation in various organs and tissues. To investigate the presence and levels of soluble TRAIL in human colostrum and milk. The levels of soluble human TRAIL were measured in human colostrum (day 2 after delivery) and breast milk (day 5 after delivery). The presence of TRAIL was also measured in infant formula. Levels of soluble TRAIL in the colostrum and mature human milk were, respectively, at least 400 and 100 fold higher than those detected in human serum. No TRAIL was detected in formula. Human soluble TRAIL is present at extremely high levels in human colostrum and human milk and might have a significant role in mediating the anti-cancer activity of human milk.

Molecular mechanism of hydroxyurea enhances K562 cell apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand

To explore the molecular mechanism via which the chemotherapeutic drug hydroxyurea (HU) enhances K562 cell apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). Chronic myelogenous leukemia-derived K562 and SVT-35 cells were treated with recombinant soluble TRAIL (rsTRAIL) alone or combined with HU for a time course, and the cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-4-sulfophenyl-2H-tetrazolium-phenazine methosulphate assay. Western blot was performed to analyze the activation of apoptosis-related protein kinases and the expression of apoptosis inhibitor molecules. The survival rates of SVT-35 and K562 cells treated with 1 μg/ml rsTRAIL for 24 hours were 32% and 93%, respectively. HU significantly increased the sensitivity of K562 cells to rsTRAIL cytotoxicity. Combination of rsTRAIL and HU resulted in the phosphorylation of rat sarcoma (RAS), mitogen-activated protein kinase/extracellular signal-regulated kinase kinase (MEK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase and in the significant reduction of apoptosis-inhibited molecule Fas associated death domain protein-like interleukin-1 beta-convening enzyme inhibitory protein and cellular inhibitor of apoptosis protein-1 in K562 cells. HU enhanced K562 cell sensitivity to rsTRAIL is mediated by Ras-MEK-ERK signaling pathway. Expression of antiapoptotic proteins cellular Fas associated death domain protein-like interleukin-1 beta-convening enzyme inhibitory protein and cellular inhibitor of apoptosis protein-1 is also down-regulated during this process. These results may through light on the therapeutic study of human chronic myelogenous leukemia.

277 Serum Soluble Trail Levels in Patients With Severe Persistent Allergic Asthma

BackgroundThe pathogenesis of allergic asthma and other allergic conditions are believed to be closely interrelated because of the similar dynamics of allergy-inducing cells and molecules, and the independent evidence for their clinical overlap. In this study we compare the diseases and the effect of Omalizumab treatment on the dynamics of cell apoptosis regulating molecules.MethodsIn the first group, 6 males and 8 females (a total of 14 patients) were selected with severe persistent asthma with a mean age of 42.4 years (Table I). All patients received omalizumab therapy for 4 months, with treatment administered every 2 weeks. Symptoms and severity of allergic reactions were recorded before and after treatment with omalizumab. Clinical changes and adverse effects were assessed and recorded at each patient visit. The second group consisted of 14 newly diagnosed allergic asthma patients with mean age was 43.8 years. All of these patients were followed up in the Immunology Allergy Clinic of the Antalya Education and Training Hospital, and were evaluated by clinical status. The third group consisted of 14 healthy volunteers, with no difference in age and sex (mean age was 43,3 years. Serum sTRAIL levels in all individuals (patients and healthy controls) were measured by a sandwich enzyme-linked immunosorbent assay (Diaclone, France).ResultsThere were no differences between the healthy controls, newly diagnosed allergic asthma patients and non-treated severe persistent allergic asthma patients during the active phase (P < 0.05). Interestingly, the variance levels in patients who received omalizumab treatment were significantly lower than the healthy controls.ConclusionsIn summary, we speculate that the physiological functions of sTRAIL in allergic conditions, and the elucidation of the molecular mechanisms by which sTRAIL: TRAIL receptor signals cells, will be of significant interest to the scientific allergy community in the coming years. Our study provides a novel perspective on severe persistent allergic asthma and the effect of omalizumab treatment on cell apoptosis, using serum sTRAIL measurements.