TRAIL Receptor Research Articles

TRAIL receptor agonists convert the response of breast cancer cells to ONC201 from anti-proliferative to apoptotic.

ONC201 was initially identified as an inducer of cell death through the tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) pathway. The compound is currently being tested in patients with hematological malignancies and solid tumors, including those of the breast. We investigated strategies to convert the response of breast cancers to ONC201 from anti-proliferative to apoptotic. ONC201 treatment upregulates TRAIL and primes TRAIL-resistant non-triple negative breast cancer (TNBC) cells to undergo cell death through the extrinsic pathway. Remarkably, the addition of exogenous recombinant human TRAIL (rhTRAIL) converts the response of TRAIL-resistant non-TNBC cells to ONC201 from anti-proliferative to apoptotic in a death receptor 5 (DR5)-dependent manner in vitro. Importantly, normal fibroblasts do not undergo apoptosis following rhTRAIL plus ONC201. In vivo, MDA-MB-361 tumor growth rate is significantly reduced following treatment with a combination of ONC201 and rhTRAIL as compared to control tumors. Natural killer (NK) cells which use TRAIL to kill DR5-expressing cancer cells, exhibit greater cytotoxicity against ONC201-treated breast cancer cells compared to controls. rhTRAIL also converts the response of cells from other tumor types to ONC201 from anti-proliferative to apoptotic. A monoclonal DR5-agonistic antibody converts the response of non-TNBC cells to ONC201 from anti-proliferative to apoptotic. Our findings describe a novel therapeutic strategy that potently converts the response of a cancer cell to ONC201 from anti-proliferative to apoptotic. This approach may be clinically relevant and has potential to induce tumor regression of patient tumors with relative resistance to ONC201 monotherapy.

Selinexor Sensitizes TRAIL-R2-Positive TNBC Cells to the Activity of TRAIL-R2xCD3 Bispecific Antibody.

Triple-negative breast cancer (TNBC) is an aggressive disease with poor prognosis and limited therapeutic options. Recent advances in the immunotherapy field have enabled the development of new treatment strategies, among which the use of bispecific antibodies (BsAbs), able to redirect T cells against tumors, has shown promising results. In particular, a BsAb that uses TNF-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) as a target was constructed and demonstrated good results in redirecting CD3+ T cells to kill TRAIL-R2-expressing TNBC cells. In the present study, we investigated whether treatment with selinexor, a selective inhibitor of nuclear export (SINE) targeting exportin-1/chromosome maintenance protein 1 (XPO1/CRM1), could potentiate the antitumor activity of this BsAb. In combination experiments, we found that selinexor-exposed TNBC cells exhibited greater growth inhibition when treated with the TRAIL-R2xCD3 BsAb than that expected by simple additivity. Similarly, the apoptosis rate in selinexor/TRAIL-R2xCD3 BsAb-treated TNBC cells was significantly higher than that observed after exposure to either single agent. Together, our results suggest that the combination of selinexor and TRAIL-R2xCD3 BsAb can be a viable anticancer strategy and indicate this treatment as a promising therapeutic option for TNBC patients.

Mcl-1 targeting strategies unlock the proapoptotic potential of TRAIL in melanoma cells.

TNF-related apoptosis-inducing ligand (TRAIL) induces apoptosis selectively in cancer cells. For melanoma, the targeting of TRAIL signaling appears highly attractive, due to pronounced TRAIL receptor expression in tumor tissue. However, mechanisms of TRAIL resistance observed in melanoma cells may limit its clinical use. The Bcl-2 family members are critical regulators of cell-intrinsic apoptotic pathways. Thus, the antiapoptotic Bcl-2 protein myeloid cell leukemia 1 (Mcl-1) is overexpressed in many tumor types and was linked to chemotherapy resistance in melanoma. In this study, we evaluated the involvement of antiapoptotic Bcl-2 proteins (Bcl-2, Bcl-xL , Bcl-w, Mcl-1, Bcl-A1, and Bcl-B) in TRAIL resistance. They were targeted by small interfering RNA-mediated silencing in TRAIL-sensitive (A-375, Mel-HO) and in TRAIL-resistant melanoma cell lines (Mel-2a, MeWo). This highlighted Mcl-1 as the most efficient target to overcome TRAIL resistance. In this context, we investigated the effects of Mcl-1-targeting microRNAs as well as the Mcl-1-selective inhibitor S63845. Both miR-193b and S63845 resulted in significant enhancement of TRAIL-induced apoptosis, associated with decreased cell viability. Apoptosis induction was mediated by caspase-3 processing as well as by Bax and Bak activation, indicating the critical involvement of intrinsic apoptosis pathways. These data may indicate a high relevance of Mcl-1 targeting also in melanoma therapy. Furthermore, the data may suggest to consider the use of the tumor suppressor miR-193b as a strategy for countering TRAIL resistance in melanoma.

Andrographolide sensitizes human renal carcinoma cells to TRAIL‑induced apoptosis through upregulation of death receptor 4

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) selectively induces apoptosis in cancer cells, with minimal toxicity to normal tissues. However, accumulating evidence suggests that certain cancer types are insensitive to TRAIL signaling. The aim of this study was to identify an effective combination regimen, which can overcome TRAIL resistance in renal cancer cell. Herein, we found that human renal carcinoma cells (RCCs) are widely resistant to TRAIL-mediated growth inhibition and subsequently identified that andrographolide (Andro), a major constituent of Andrographis paniculate, an annual herbaceous plant in the family Acanthaceae, counteracts TRAIL resistance in RCCs. Combined treatment with TRAIL and Andro suppressed cell viability as determined by MTS and proliferation as determined by EdU in a dose-dependent manner and inactivated the clonogenic and migration ability of RCCs. Andro significantly enhances TRAIL-mediated cell cycle arrest at the G2/M phase as determined by flow cytometry and senescence. Moreover, Andro restored TRAIL signaling, which in turns activated pro-apoptosis caspases as determined by immunoblot assay. The TRAIL receptor, death receptor (DR)4, but not DR5, was found to be significantly upregulated in Andro-treated RCC cells, which contributed to the role of Andro as a TRAIL sensitizer. The present study demonstrated that the combined treatment of Andro and TRAIL has potential therapeutic value against renal cancer.

Abstract 4668: Human CYP1B1 prevents TRAIL-DR4-mediated cancer cell apoptosis through downregulation of miR-375

Abstract Human cytochrome P450 1B1 (CYP1B1) is an important enzyme that catalyzes metabolism of 17β-estradiol (E2) to catechol estrogens, including carcinogenic metabolite 4-hydroxyestradiol (4-OHE2). CYP1B1 may play a crucial role in estrogen-mediated carcinogenesis since CYP1B1 shows tumor-specific expression pattern in various hormone-responsive tissues. However, the detailed mechanism of CYP1B1-dependent carcinogenesis remains still unclear. Here, we investigated the association between TRAIL, DR4, and CYP1B1 expression in human tumor cells, including MCF-7, MDA-MB-231, and HeLa cells. CYP1B1 can inhibit the expression and release of TRAIL simultaneously with the expression of the death receptor DR4/5, known as TRAIL receptors, to prevent apoptosis. Furthermore, we found that CYP1B1 represses the transcription of DR4 by inducing DNA methylation in the promoter region of DR4. In addition, we revealed that CYP1B1 regulates TRAIL and DR4 through activation of Sp1 transcription factor. CYP1B1 and its enzymatic product, 4-OHE2, promote Sp1 expression levels in both mRNA and protein levels. Interestingly, CYP1B1 elevated Sp1 through downregulation of miR-375, which is a candidate tumor suppressive microRNA and transcriptional inhibitor of Sp1. Taken together, our data suggest that CYP1B1 inhibits TRAIL-DR4-mediated cancer cell apoptosis through induction of Sp1 through repression of miR-375, which promotes cancer cell survival. Citation Format: Yeo-Jung Kwon, Dong-Jin Ye, Huoung-Seok Baek, Sangyun Shin, Tae-Uk Kwon, Eunah Cho, Hong-Gyu Ahn, Youngjin Chun. Human CYP1B1 prevents TRAIL-DR4-mediated cancer cell apoptosis through downregulation of miR-375 [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4668.

Abstract 6225: Addition of TRAIL receptor agonists after treatment with ONC201 or ONC212 converts pancreatic cancer cells from anti-proliferative to apoptotic in vitro

Abstract The 7% five-year survival rate for pancreatic cancer patients has remained unchanged for decades; the need for novel therapeutic interventions is imminent. ONC201 is the founding member of the impridone class, a class of orally bioavailable small molecules which show efficacy in multiple tumor types. ONC201 and ONC212, a fluorinated imipridone, have been shown to be potent inducers of the tumor necrosis factor related apoptosis inducing ligand (TRAIL) pathway. Both compounds are currently in clinical trials. In the context of pancreatic cancer, ONC201 and ONC212 induce either apoptotic or anti-proliferative effects. Additionally, both compounds activate the integrated stress response leading to DR5 upregulation in various cell types. We hypothesized that exogenous addition of TRAIL receptor agonists after pre-treatment with ONC201 or ONC212 could convert cells from anti-proliferative to apoptotic. Here, we examined both rhTRAIL and TLY012, a novel TRAIL receptor agonist with a substantially improved half-life. Pancreatic cancer cell lines were screened for synergy when treated with ONC201 or ONC212 for 72 hours followed by either rhTRAIL or TLY012 for 4 hours. Four cell lines (AsPC-1, BxPC3, Capan-1, and PANC-1) showed potent synergy with both rhTRAIL and TLY012. Growth inhibition was assessed through both Cell-Titer Glo and colony assays. Apoptotic synergy was determined using Cell-Titer Glo, western blots for PARP cleavage, and sub-G1 flow cytometric assays. Further analysis showed that ONC201 activates the integrated stress response and primes pancreatic cancer cells for TRAIL-induced apoptosis through regulation of key proteins. Upregulation of the integrated stress response and downregulation of XIAP, c-FLIP, and Bcl-XL was observed after treatment with ONC201 in BxPC3 and PANC-1 cell lines. The combination of ONC201 and TRAIL receptor agonists was non-toxic to human foreskin fibroblasts. Future experiments aim to examine G1 arrest after treatment with ONC201 and ONC212 via western blot and flow cytometry, to confirm surface expression of TRAIL and DR5 via flow cytometry, and to determine efficacy in pancreatic cancer xenografts. Taken together, these data indicate a novel therapeutic strategy for treatment of patients with ONC201 and ONC212 resistant pancreatic tumors. Citation Format: Aakash V. Jhaveri, Lanlan Zhou, Isacco Ferarrini, Young Lee, Wafik S. El-Deiry. Addition of TRAIL receptor agonists after treatment with ONC201 or ONC212 converts pancreatic cancer cells from anti-proliferative to apoptotic in vitro [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6225.

Multi-proteomic approach to predict specific cardiovascular events in patients with diabetes and myocardial infarction: findings from the EXAMINE trial.

Patients with diabetes who had a recent myocardial infarction (MI) are at high risk of cardiovascular events. Therefore, risk assessment is important for treatment and shared decisions. We used data from EXAMINE trial to investigate whether a multi-proteomic approach would provide specific proteomic signatures and also improve the prognostic capacity for determining the risk of cardiovascular death, MI, stroke, heart failure [HF], all-cause death, and combinations of these outcomes. 93 circulating proteins (92 from the Olink® CVDII plus troponin) were assessed in 5131 patients. Cox, competing risks, and reclassification measures were applied. The clinical model showed good discrimination and calibration for all outcomes. On top of theclinical model that included age, sex, smoking, diabetes duration, history of MI (prior to the index MI of inclusion), history of HF hospitalization, history of stroke, atrial fibrillation, hypertension, systolic blood pressure, statin therapy, estimated glomerular filtration rate, and study treatment (alogliptin or placebo), troponin and BNP added prognostic information to the composite of cardiovascular death, MI, or stroke (∆C-index + 5%) and cardiovascular death alone (∆C-index + 7%). Troponin, BNP, and TRAILR2 added prognostic information on all-cause death and the composite of cardiovascular death or HF hospitalization. HF hospitalization alone was improved by adding BNP and Gal-9. For MI, troponin, FGF23, and AMBP added prognostic value; whereas for stroke, only troponin added prognostic value (multi-proteomics improved C-index > 3% [p < 0.001] for all the studied outcomes). The addition of the final biomarker selection to the clinical model improved event reclassification (cNRI from + 23% to + 64%). Specifically, the addition of the biomarkers allowed a better classification of patients at low risk (as having "true" low risk) and patients and high risk (as having "true" high risk). These results were consistent for all the studied outcomes with even more marked differences in the fatal events. The addition of multi-proteomic biomarkers to a clinical model in this population with diabetes and a recent MI allowed a better risk prediction and event reclassification, potentially helping for better risk assessment and targeted treatment decisions. T2D type 2 diabetes, MI myocardial infarction, CV cardiovascular, HFH heart failure hospitalization, Δ delta, cNRI continuous net reclassification index, BNP brain natriuretic peptide, TRAILR2 trail receptor 2 (or death receptor 5), Gal-9 galectin-9, FGF23 fibroblast growth factor 23.

Abstract 4808: ONC201 decreases protein chaperone ClpX to unleash mitochondrial protease ClpP activity, intregrated stress response and tumor cell death

Abstract Brain tumors are one of the most lethal cancers in children and young adults. We previously reported that first-in-class small-molecule imipridone ONC201 can antagonize dopamine receptor D2 (DRD2), inactivate ERK/AKT, induce the integrated stress response (ISR), upregulate pro-apoptotic TRAIL receptor DR5, deplete cancer stem cells, and induce growth arrest or cell death in tumor cells. ONC201 crosses the blood-brain barrier and has induced durable tumor regressions in adult and pediatric H3K27M-mutant glioma patients. We hypothesized that ONC201 may synergize with radiotherapy and temozolomide in brain tumors. Glioblastoma (GBM: SNB19, T98G and U251), diffuse intrinsic pontine glioma (DIPG: SU-DIPG-IV and SU-DIPG-36) and atypical teratoid rhabdoid tumor (ATRT: BT-12, BT-16) cell lines were tested using cell viability or colony formation assays with ONC201 up to 20 μM alone or in combination with radiotherapy up to 8 Gy and temozolomide up to 100 μM. We observed synergy between ONC201 and radiation and temozolomide by multiple assays with the best combination index of 0.31 under the treatment of 0.625 μM ONC201, 25 μM TMZ and 4 Gy irradiation in cell viability assay. We observed induction of PKA substrate phosphorylation as a marker of DRD2 antagonism, induction of ATF4 as a marker of ISR activation, and multiple markers of cell death in treated brain tumor cells. Mitochondrial dysfunction induced by ONC201 was greatly reflected in reduction of maximal cell respiration in brain tumor cell lines. ClpXP is a proteolytic machine in mitochondria comprising of the protein chaperone ClpX and protease ClpP, a recently described binding target of ONC201. We have observed that ONC201 induced cytotoxicity depends on ClpP and knockdown of ClpP strongly protects multiple human cancer cell lines from ONC201-mediated (but not other drugs, e.g. temozolomide) cytotoxicity. The ClpX protein level decreased dramatically upon ONC201 treatment. We are exploring the potential interplay between ClpP, dopamine receptors, the ISR and TRAIL signaling pathways after single agent or combinatorial treatments. Our data suggests that ONC201 may be combined synergistically with temozolomide or radiation to address gliomas, along with potential pharmacodynamic biomarkers. The results implicate ClpX and ClpP in downstream cell death induction following ONC201 treatment of brain tumor cells. Citation Format: Lanlan Zhou, Howard P. Safran, Michael J. Glantz, Wafik S. El-Deiry. ONC201 decreases protein chaperone ClpX to unleash mitochondrial protease ClpP activity, intregrated stress response and tumor cell death [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 4808.

HIF-1α Mediates TRAIL-Induced Neuronal Apoptosis via Regulating DcR1 Expression Following Traumatic Brain Injury.

Background: Neuronal apoptosis involved in secondary injury following traumatic brain injury (TBI) significantly contributes to the poor outcomes of patients with TBI. The tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) can selectively induce apoptosis of tumor cells. Hypoxia factor (HIF) 1α is a controversial factor that mediates the neuronal apoptotic pathway. Herein, we hypothesize that HIF-1α may mediate the TRAIL-induced neuronal apoptosis after TBI.Methods: We used Western blots and immunofluorescence to study the expression and cell localization of TRAIL and death receptor 5 (DR5) after TBI in rats. Soluble DR5 (sDR5) administration was used to block the TRAIL-induced neuronal death and neural deficits. HIF-1α inhibitor 2ME and agonist DMOG were used to study the role of HIF-1α in TRAIL-induced neuronal death. Meanwhile, HIF-1α siRNA was used to investigate the role of HIF-1α in TRAIL-induced neuronal death in vitro.Results: The expressions of microglia-located TRAIL and neuron-located DR5 were significantly upregulated after TBI. sDR5 significantly attenuated TRAIL-induced neuronal apoptosis and neurological deficits. 2ME decreased neuronal apoptosis, lesion area, and brain edema and improved neurological function via increased expression of TRAIL decoy receptor 1 (DcR1), which inhibited TRAIL-induced apoptosis after TBI. The administration of DMOG produced the opposite effect than did 2ME. Similarly, HIF-1α siRNA attenuated TRAIL-induced neuronal death via increased DcR1 expression in vitro.Conclusion: Our findings suggested that the TRAIL/DR5 signaling pathway plays an important role after neuronal apoptosis after TBI. HIF-1α mediates TRAIL-induced neuronal apoptosis by regulating DcR1 expression following TBI.

Oral recombinant methioninase increases TRAIL receptor-2 expression to regress pancreatic cancer in combination with agonist tigatuzumab in an orthotopic mouse model.

Methionine addiction is a fundamental and general hallmark of cancer. Gene expression analysis showed that methionine restriction (MR) of methionine-addicted cancer cells increases TNF-related apoptosis-induced ligand receptor-2 (TRAIL-R2) expression. Here, we determined the effects of MR on TRAIL-R2 targeted therapy in pancreatic cancer by the TRAIL-R2 agonist tigatuzumab. Human pancreatic cancer cell lines were cultured in control or methionine-free medium. The effects of MR on TRAIL-R2 expression and sensitivity to tigatuzumab were evaluated in vitro. An orthotopic pancreatic cancer mouse model was established to evaluate the efficacy of MR using oral recombinant methioninase (o-rMETase), and the efficacy of tigatuzumab and their combination. MR enabled tigatuzumab-induced apoptosis, by increasing TRAIL-R2 expression in pancreatic cancer cells in vitro. The protein expression level of the melanoma-associated antigen MAGED2, which reduces TRAIL-R2 expression, was decreased by MR. In the orthotopic pancreatic cancer mouse model, o-rMETase increased TRAIL-R2 expression level in the tumors and enabled the antitumor efficacy of tigatuzumab. MR, effected by o-rMETase, enabled the efficacy of the TRAIL-R2 agonist tigatuzumab by increasing TRAIL-R2 expression in pancreatic cancer. Our results suggest that o-rMETase has clinical potential for treating pancreatic cancer.

Use of proteomics to identify biomarkers associated with chronic kidney disease and long-term outcomes in patients with myocardial infarction.

Patients with chronic kidney disease (CKD) have poor outcomes following myocardial infarction (MI). We performed an untargeted examination of 175 biomarkers to identify those with the strongest association with CKD and to examine the association of those biomarkers with long-term outcomes. A total of 175 different biomarkers from MI patients enrolled in the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART) registry were analysed either by a multiple reaction monitoring mass spectrometry assay or by a multiplex assay (proximity extension assay). Random forests statistical models were used to assess the predictor importance of biomarkers, CKD and outcomes. A total of 1098 MI patients with a median estimated glomerular filtration rate of 85mLmin-1 /1.73m2 were followed for a median of 3.2years. The random forests analyses, without and with adjustment for differences in demography, comorbidities and severity of disease, identified six biomarkers (adrenomedullin, TNF receptor-1, adipocyte fatty acid-binding protein-4, TNF-related apoptosis-inducing ligand receptor 2, growth differentiation factor-15 and TNF receptor-2) to be strongly associated with CKD. All six biomarkers were also amongst the 15 strongest predictors for death, and four of them were amongst the strongest predictors of subsequent MI and heart failure hospitalization. In patients with MI, a proteomic approach could identify six biomarkers that best predicted CKD. These biomarkers were also amongst the most important predictors of long-term outcomes. Thus, these biomarkers indicate underlying mechanisms that may contribute to the poor prognosis seen in patients with MI and CKD.

P-169 A first-in-human phase Ia/b, open-label, multicentre, dose-escalation study of BI 905711 in patients with advanced gastrointestinal cancers

Activation of the tumour necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAILR2) induces apoptosis via caspase activation. Hence, targeting TRAILR2 is an attractive therapeutic strategy; however, early trials of TRAILR2 agonists resulted, in some cases, in severe hepatotoxicity that may have been due to TRAILR2 activation on hepatocytes. Cadherin 17 (CDH17), a membrane protein highly expressed in gastrointestinal (GI) cancers, is not expressed in normal hepatic cells. Thus, the hepatotoxicity of prior TRAILR2 agonists may be avoided through crosslinking with CDH17.

Immunomodulation of NK Cells by Ionizing Radiation.

Natural killer (NK) cells play a critical role in the antitumor immunity. Ionizing radiation (IR) has a pronounced effect on modifying NK cell biology, while the molecular mechanisms remain elusive. In this review, we briefly introduce the anti-tumor activity of NK cells and summarize the impact of IR on NK cells both directly and indirectly. On one hand, low-dose ionizing radiation (LDIR) activates NK functions while high-dose ionizing radiation (HDIR) is likely to partially impair NK functions, which can be reversed by interleukin (IL)-2 pretreatment. On the other hand, NK functions may be adjusted by other immune cells and the alternated malignant cell immunogenicity under the settings of IR. Various immune cells, such as the tumor-associated macrophage (TAM), dendritic cell (DC), regulatory T cell (Treg), myeloid-derived suppressor cell (MDSC), and tumor exhibited ligands, such as the natural killer group 2 member D ligand (NKG2DL), natural cytotoxicity receptors (NCR) ligand, TNF-related apoptosis-inducing ligand-receptor (TRAIL-R), and FAS, have been involved in this process. Better understanding the molecular basis is a promising way in which to augment NK-cell-based antitumor immunity in combination with IR.

Enhancing radiation response by a second-generation TRAIL receptor agonist using a new in vitro organoid model system

BackgroundFor many cancer types, including colorectal carcinoma (CRC), combined modality treatments have shown to improve outcome, but are frequently associated with significant toxicity, illustrating the need for new therapeutic approaches. Based on preclinical data, TRAIL receptor agonists appeared to be promising agents for cancer therapy especially in combination with DNA damaging regimens. Here, we present the combination of the second-generation TRAIL receptor agonist APG-880 with radiation in a new and clinically relevant 3D model system. MethodsTo investigate the effect of APG-880 in combination with radiation we performed short-term cytotoxicity and long-term clonogenic survival assays in established CRC cell lines, and in tumor organoids derived from colon cancer patients. ResultsAPG-880 is a potent inducer of apoptosis in CRC cell lines and in patient-derived CRC organoids. Furthermore, a supra-additive effect on cytotoxicity was found when APG-880 and radiation were combined simultaneously, with combination indices around 0.7. Lastly, in the long-term survival assays, we demonstrated a radiosensitizing effect of APG-880 with dose enhancement factors between 1.3 and 1.5. ConclusionsIn a new, clinically relevant CRC-organoid model system we demonstrated a more than additive combined effect between the second-generation TRAIL receptor agonist APG-880 and radiation.

SO025DCR2 ACCELERATES RENAL FIBROSIS AND TUBULAR CELL SENESCENCE BY PHOSPHORYLATING TYR 194 OF PRDX1 IN DIABETIC NEPHROPATHY

Abstract Background and Aims Cell senescence of renal tubular epithelial cells (RTECs), which is involved in renal tubulointerstitial fibrosis (TIF), is a key event in the progression of diabetic nephropathy (DN). However, the underlying mechanism remains unclear. This study aims to investigate the role and mechanism of decoy receptor 2 (DcR2) in TIF and cell senescence of RTECs. Method Streptozotocin (STZ)-induced DN mice model and high glucose (HG)-induced cell senescent model were constructed. The expression of DcR2 were regulated by ultrasound-mediated gene transfer of DcR2-siRNA or DcR2-overexpression plasmid in vivo. The co-expression of DcR2 with senescent markers (p16, p21 and SA-β-gal) and fibrotic markers (FN, collagen I and α-SMA). The interaction of DcR2 and its ligand TRAIL and antagonistic receptor DR5 were detected by laser confocal and Co-IP. The DcR2-interaction proteins were screened in renal tissue of DN patients and HG-induced cells by Co-IP combining with LC-MS/MS. The interaction of DcR2 and PRDX1 was validated by Co-IP, pull down assay and immunofluorescence co-staining. Peroxidase activity of PRDX1 was assessed by the kits of reactive oxygen species (ROS) and specific 2-cys peroxidase activity. The level of PRDX1 phosphorylation was measured through WB and the phosphorylated site were studied by wild-type PRDX1 and mutant Tyr194 PRDX1. Results DcR2 was co-expressed with senescent markers and co-localization with fibrotic markers in DN patients and STZ-DN mice. Knockdown of DcR2 effectively decreased renal fibrosis and tubular cell senescence in STZ-induced DN mice. However, DcR2 overexpression showed the opposite effects. DcR2 didn’t interacted with TRAIL or DR5 in vivo and vitro. The following study indicated that PRDX1 is a novel DcR2-interacting protein using quantitative proteomics, which have peroxidase and antioxidant activity in cytoplasm. The interaction of DcR2-PRDX1 mediated RTEC senescence in vitro. Knockdown of DcR2 inhibited the level of ROS and promoted the peroxidase activity of PRDX1, resulting in oxidative stress and cell senescence, and DcR2 overexpression presented the contrary results. DcR2 regulated the level of PRDX1 phosphorylation by interacting Tyr194 of PRDX1, and the mutant Tyr194 of PRDX1 can’t be phosphorylated by DcR2. Conclusion DcR2 mediates renal fibrosis and RTEC senescence by phosphorylating with PRDX1, suggesting DcR2 could serve as a potential therapeutic target for the amelioration of DN progression.

Genetic variations in apoptosis genes are associated with acute adverse events in postoperative rectal cancer patients receiving concurrent chemoradiotherapy

Objective: To investigate the associations between the genetic variations of apoptosis genes and the adverse events of postoperative concurrent chemoradiotherapy in patients with rectal cancer. Methods: We enrolled 362 patients with stage Ⅱ to Ⅲ rectal cancer who received concurrent chemoradiotherapy. Whole blood sample (2 ml) was collected from patient at the time of enrollment before therapy. Sequenom MassARRAY was used to detect the genotypes of 29 haplotype-tagging single nucleotide polymorphisms (htSNPs) in eight apoptosis genes, including Fas cell surface death receptor(FAS), Fas ligand(FASL), apoptotic peptidase activating factor 1(APAF1), BCL2 associated X(BAX), TNF-related apoptosis-inducing ligand(TRAIL), TNF-related apoptosis-inducing ligand receptor 1(TRAILR1), TNF-related apoptosis-inducing ligand receptor 2(TRAILR2) and caspase-7(CASP7). The associations between genotypes and adverse events of chemoradiotherapy were measured by unconditional logistic regression model. Results: Three hundred and sixty two patients were treated with total mesorectal excision surgery followed by a total radiation dose of 50 Gy applied in 25 fractions over a period of 5 weeks concurrently with daily administration of capecitabine (1 600 mg/m(2) per day, continuously for 2 weeks and taking a week off every 21-day cycle). One hundred and six patients (29.3%) had grade≥2 myelosuppression. Three SNPs associated with the risk of grade ≥2 myelosuppression included FAS rs1468063 (OR=1.51, 95% CI: 1.07-2.15, P=0.020), APAF1 rs11296996 (OR=0.69, 95% CI: 0.49-0.98, P=0.039) and BAX rs4645904 (OR=0.69, 95% CI: 0.50-0.97, P=0.030). One hundred and sixty one patients (44.5%) developed grade≥2 diarrhea. Five SNPs that significantly associated with risk of grade≥2 diarrhea included APAF1 rs11296996 (OR=1.42, 95% CI: 1.02-2.00, P=0.040), rs74619561 (OR=2.16, 95% CI: 1.27-3.68, P=0.005), CASP7 rs12263370 (OR=1.67, 95% CI: 1.05-2.66, P=0.029), rs12247479 (OR=1.85, 95% CI: 1.12-3.08, P=0.017) and TRAIL rs112822654 (OR=0.68, 95% CI: 0.48-0.96, P=0.027). The remaining SNPs were not related to the adverse events of chemoradiotherapy (all P>0.05). Grade≥2 myelosuppression occurred less frequently in male than in female (P=0.046); Surgical treatment and tumor location had great impact on the occurrence of grade≥2 diarrhea (all P<0.001) and dermatitis (all P<0.05). Conclusions: The genetic variations of FAS, APAF1, BAX, TRAIL and CASP7 are related to the adverse events of concurrent chemoradiotherapy in patients with rectal cancer, which may be potential genetic biomarkers for individualized treatment of rectal cancer.

Inhibition of Importin β1 Augments the Anticancer Effect of Agonistic Anti-Death Receptor 5 Antibody in TRAIL-resistant Tumor Cells.

TNF-related apoptosis-inducing ligand (TRAIL) and an agonistic antibody against the death-inducing TRAIL receptor 5, DR5, are thought to selectively induce tumor cell death and therefore, have gained attention as potential therapeutics currently under investigation in several clinical trials. However, some tumor cells are resistant to TRAIL/DR5-induced cell death, even though they express DR5. Previously, we reported that DR5 is transported into the nucleus by importin β1, and knockdown of importin β1 upregulates cell surface expression of DR5 resulting in increased TRAIL sensitivity in vitro Here, we examined the impact of importin β1 knockdown on agonistic anti-human DR5 (hDR5) antibody therapy. Drug-inducible importin β1 knockdown sensitizes HeLa cells to TRAIL-induced cell death in vitro, and exerts an antitumor effect when combined with agonistic anti-hDR5 antibody administration in vivo Therapeutic importin β1 knockdown, administered via the atelocollagen delivery system, as well as treatment with the importin β inhibitor, importazole, induced regression and/or eradication of two human TRAIL-resistant tumor cells when combined with agonistic anti-hDR5 antibody treatment. Thus, these findings suggest that the inhibition of importin β1 would be useful to improve the therapeutic effects of agonistic anti-hDR5 antibody against TRAIL-resistant cancers.

Effects of Sulfonylureas Treatment on Apoptosis, Total Superoxide Dismutase activity and Some Biochemical Parameters in Type 2 Diabetic Patients

The purpose of this analysis was to evaluate the the influence of anti-diabetic drugs (sulfonylureas) in type two diabetic patients and the risk of developing diabetes complications related to kidney disease (Diabetic Nephropathy ) compared to healthy subjects by measuring influence of some apoptosis factors ( serum Tumor necrosis factor soluble Receptor-1(TNF-R1) and TNF-related apoptosis-inducing ligand receptor-2 (TRAIL-R2)) concentrations , Serum Small mothers against decapentaplegic (Smad1 ) as anew marker of diabetic nephropathy (DN) ,Superoxide dismutase concentration (SOD) ,Glycated hemoglobin (HbA1c%) , Fasting plasma glucose (FPG) ,insulin concentration , insulin resistance (IR) ,urea and creatinine .A samples of convenience composed of 17 type 2 diabetic patients with sulfonylureas monotherapy and 17 normal subjects above the age of 40 years were recruited . Age ,duration of disease and body mass index (BMI) was created. The mean levels of Smad1 and TRAIL- R2 in diabetics with sulfonylureas treatment , they were significantly higher compared to control subjects, while the means of SOD have low level in diabetic subjects , and the mean levels of TNF-R1 and IR were non-significant in diabetic with Sulfonylureas treatment compared to control subjects.

Enhancing the antitumor activity of an engineered TRAIL-coated oncolytic adenovirus for treating acute myeloid leukemia

The use of oncolytic viruses has emerged as a promising therapeutic approach due to the features of these viruses, which selectively replicate and destroy tumor cells while sparing normal cells. Although numerous oncolytic viruses have been developed for testing in solid tumors, only a few have been reported to target acute myeloid leukemia (AML) and overall patient survival has remained low. We previously developed the oncolytic adenovirus rAd5pz-zTRAIL-RFP-SΔ24E1a (A4), which carries the viral capsid protein IX linked to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and results in increased infection of cancer cells and improved tumor targeting. To further improve the therapeutic potential of A4 by enhancing the engagement of virus and leukemia cells, we generated a new version of A4, zA4, by coating A4 with additional soluble TRAIL that is fused with a leucine zipper-like dimerization domain (zipper). ZA4 resulted in enhanced infectivity and significant inhibition of the proliferation of AML cells from cell lines and primary patient samples that expressed moderate levels of TRAIL-related receptors. ZA4 also elicited enhanced anti-AML activity in vivo compared with A4 and an unmodified oncolytic adenoviral vector. In addition, we found that the ginsenoside Rh2 upregulated the expression of TRAIL receptors and consequently enhanced the antitumor activity of zA4. Our results indicate that the oncolytic virus zA4 might be a promising new agent for treating hematopoietic malignancies such as AML.

TWEAK Promotes the Proliferation of Squamous Cell Carcinoma Cells Through Activating cIAP1 Signals.

Recent studies showed that tumor necrosis factor (TNF)-like weak inducer of apoptosis (TWEAK) induces the proliferation of squamous cell carcinoma (SCC) cells. However, the precise mechanism underlying such effect of TWEAK remains unclear. This study was designed to elucidate the role of cellular inhibitor of apoptosis 1 (cIAP1) in TWEAK-induced proliferation of SCC cells. Human SCC cells (SCC-13, A431, and SCC-9) were cultured in vitro, receiving the stimulation of TWEAK or TNF-related apoptosis-inducing ligand (TRAIL). We found that TWEAK induced cytoplasmic cIAP1 importation and RIP1 ubiquitination in cells, followed by the activation of canonical nuclear factor kappa B signals. MV1, a cIAP1 inhibitor, abrogated TWEAK-induced proliferation of these cells. Moreover, the interaction between TWEAK and its receptor, fibroblast growth factor-inducible 14 (Fn14), enhanced the expression of TRAIL receptor types 3 and 4 (TRAIL-R3/4). Furthermore, the transfection of TRAIL-R3/4 siRNA abrogated the promotion effect of TWEAK on SCC-13 cell proliferation and cIAP1 expression. Therefore, TWEAK/Fn14 interaction promotes the proliferation of SCC cells through activating cIAP1 signals. Targeting the downstream cIAP1 signals might attenuate the effect of TWEAK on SCC cells.