METTL16 deficiency attenuates apoptosis through translational control of extrinsic death receptor during nutrient deprivation

METTL16 is a well-characterized m6A methyltransferase that has been reported to contribute to tumorigenesis in various types of cancer. However, the effect of METTL16 on tumor progression under restricted nutrient conditions, which commonly occur in tumor microenvironment, has yet to be elucidated. Herein, our study initially reported the inhibitory effect of METTL16 depletion on apoptosis under amino acid starvation conditions. Mechanistically, we determined that the METTL16 knockdown represses the expression of extrinsic death receptors at both transcription and translation levels. Depletion of METTL16 prevented protein synthesis of GCN2, resulting in diminished ATF4 expression in a GCN2-eIF2α-dependent manner. Reduction of ATF4 further declined the expression of apoptotic receptor protein DR5. Meanwhile, METTL16 deficiency directly hampered protein synthesis of FADD and DR5, thereby impairing apoptosis and promoting cancer cell survival. Taken together, our study provides novel evidence for the involvement of METTL16 in regulating cancer progression, suggesting that METTL16 as a potential therapeutic target for cancer treatment.

Non-oxidized and oxidized flaxseed orbitides differently induce HepG2 cell apoptosis: involvement of cellular uptake and membrane death receptor DR4

BACKGROUND

Flaxseed orbitides have health-promoting properties, particularly potent anti-cancer activity. However, flaxseed orbitides containing a methionine structure, such as [1-9-NαC]-linusorb B2 (CLB), are easily oxidized to sulfoxide ([1-9-NαC],[1-Rs,Ss-MetO]-linusorb-B2 (CLC)) and sulfone ([1-9-NαC], [1-MetO]-linusorb B2 (CLK)), with CLC having less anti-cancer ability than CLB. It is unclear why oxidized flaxseed orbitides are less effective against cancer than non-oxidized flaxseed orbitide.

RESULTS

Non-oxidized ([1-9-NαC]-linusorb-B3 (CLA) and CLB) and oxidized (CLC and CLK) flaxseed orbitides were found to significantly upregulate the levels of pro-apoptotic proteins, including Bax/Bcl-2, CytoC, caspase-3, and caspase-8, in a dose-dependent manner, with non-oxidized flaxseed orbitides being more effective than oxidized flaxseed orbitides. Mechanically, the cellular absorption of non-oxidized flaxseed orbitides was higher than that of oxidized flaxseed orbitides. Moreover, the significant fluorescence quenching of DR4 protein by flaxseed orbitides (especially non-oxidized orbitides) indicated the formation of a DR4-orbitide complex. Molecular docking demonstrated that non-oxidized orbitides could easily dock into the active cavity of DR4 protein. Further blocking DR4 significantly reduced the ability of non-oxidized flaxseed orbitides to stimulate caspase-3 expression, whereas oxidized flaxseed orbitides retained this ability.

CONCLUSION

Non-oxidized flaxseed orbitides are more effective against cancer than oxidized flaxseed orbitides due to higher cellular uptake and activation of the DR4-mediated death receptor signaling pathway. © 2024 Society of Chemical Industry.

Employing Piezoelectric Mg2+-Doped Hydroxyapatite to Target Death Receptor-Mediated Necroptosis: A Strategy for Amplifying Immune Activation

Although immunogenic cell death (ICD) inducers evidently enhance the effectiveness of immunotherapy, their potential is increasingly restricted by the development of apoptosis resistance in tumor cells, poor immunogenicity, and low T-cell immune responsiveness. In this study, for the first time, piezoelectrically catalyzed Mg2+-doped hydroxyapatite (Mg-HAP) nanoparticles, which are coated with a mesoporous silica layer and loaded with ONC201 as an agonist to specifically target the death receptor DR5 on tumor cells, ultimately developing an Mg-HAP@MS/ONC201 nanoparticle (MHMO NP) system, are engineered. Owing to its excellent piezoelectric properties, MHMO facilitates the release of a significant amount of reactive oxygen species and Ca2+ within tumor cells, effectively promoting the upregulation of DR5 expression and inducing tumor cell necroptosis to ultimately overcome apoptosis resistance. Concurrently, Mg2+ released in the tumor microenvironment promotes CD8+ T receptor activation in response to the antitumor immune reaction induced by ICD. Using RNA-seq analysis, it is elucidated that MHMO can activate the NF-κB pathway under piezoelectric catalysis, thus inducing M1-type macrophage polarization. In summary, a dual-targeting therapy system that targets both tumor cells and the tumor microenvironment under piezoelectric catalysis is designed. This system holds substantial potential for advancements in tumor immunotherapy.

The outcome in patients with BRAF-mutated metastatic melanoma treated with anti-programmed death receptor-1 monotherapy or targeted therapy in the real-world setting

BACKGROUND

Immunotherapy and targeted therapy are currently two alternative backbones in the therapy of BRAF-mutated malignant melanoma. However, predictive biomarkers that would help with treatment selection are lacking.

METHODS

This retrospective study investigated outcomes of anti-programmed death receptor-1 monotherapy and targeted therapy in the first-line setting in patients with metastatic BRAF-mutated melanoma, focusing on clinical and laboratory parameters associated with treatment outcome.

RESULTS

Data from 174 patients were analysed. The median progression-free survival (PFS) was 17.0 months (95% CI; 8-39) and 12.5 months (95% CI; 9-14.2) for immunotherapy and targeted therapy, respectively. The 3-year PFS rate was 39% for immunotherapy and 25% for targeted therapy. The objective response rate was 72% and 51% for targeted therapy and immunotherapy. The median overall (OS) survival for immunotherapy has not been reached and was 23.6 months (95% CI; 16.1-38.2) for targeted therapy, with a 3-year survival rate of 63% and 40%, respectively. In a univariate analysis, age < 70 years, a higher number of metastatic sites, elevated serum LDH and a neutrophil-lymphocyte ratio above the cut-off value were associated with inferior PFS regardless of the therapy received, but only serum LDH level and the presence of lung metastases remained significant predictors of PFS in a multivariate analysis.

CONCLUSIONS

Present real-world data document the high effectiveness of immunotherapy and targeted therapy. Although targeted therapy had higher response rates, immunotherapy improved PFS and OS. While the prognostic value of LDH was confirmed, the potential use of blood cell count-derived parameters to predict outcomes needs further investigation.

The radiopharmaceutical radium-223 has immunomodulatory effects in patients and facilitates anti-programmed death receptor-1 therapy in murine models of bone metastatic prostate cancer

BACKGROUND & PURPOSE

Radium-223 (Ra223) improves survival in metastatic prostate cancer (mPC), but its impact on systemic immunity is unclear, and biomarkers of response are lacking. We examined markers of immunomodulatory activity during standard clinical Ra223 and studied the impact of Ra223 on response to immune checkpoint inhibition (ICI) in preclinical models.

MATERIALS & METHODS

We conducted a single-arm biomarker study of Ra223 in 22 bone mPC patients. We measured circulating immune cell subsets and a panel of cytokines before and during Ra223 therapy and correlated them with overall survival (OS). Using two murine mPC models-orthotopic PtenSmad4-null and TRAMP-C1 grafts in syngeneic immunocompetent mice-we tested the efficacy of combining Ra223 with ICI.

RESULTS

Above-median level of IL-6 at baseline was associated with a median OS of 358 versus 947 days for below levels; p = 0.044, from the log-rank test. Baseline PlGF and PSA inversely correlated with OS (p = 0.018 and p = 0.037, respectively, from the Cox model). Ra223 treatment was associated with a mild decrease in some peripheral immune cell populations and a shift in the proportion of MDSCs from granulocytic to myeloid. In mice, Ra223 increased the proliferation of CD8+ and CD4+ helper T cells without leading to CD8+ T cell exhaustion in the mPC lesions. In one of the models, combining Ra223 and anti-PD-1 antibody significantly prolonged survival, which correlated with increased CD8+ T cell infiltration in tumor tissue.

CONCLUSION

The inflammatory cytokine IL-6 and the angiogenic biomarker PlGF at baseline were promising outcome biomarkers after standard Ra223 treatment. In mouse models, Ra223 increased intratumoral CD8+ T cell infiltration and proliferation and could improve OS when combined with anti-PD-1 ICI.

Risk of hepatitis B virus reactivation and its effect on survival in advanced hepatocellular carcinoma patients treated with hepatic arterial infusion chemotherapy and lenvatinib plus programmed death receptor-1 inhibitors

Background

Hepatitis B virus (HBV) reactivation is a common complication in hepatocellular carcinoma (HCC) patients treated with chemotherapy or immunotherapy. This study aimed to evaluate the risk of HBV reactivation and its effect on survival in HCC patients treated with HAIC and lenvatinib plus PD1s.

Methods

We retrospectively collected the data of 213 HBV-related HCC patients who underwent HAIC and lenvatinib plus PD1s treatment between June 2019 to June 2022 at Sun Yat-sen University, China. The primary outcome was the risk of HBV reactivation. The secondary outcomes were overall survival (OS), progression-free survival (PFS), and treatment-related adverse events.

Results

Sixteen patients (7.5%) occurred HBV reactivation in our study. The incidence of HBV reactivation was 5% in patients with antiviral prophylaxis and 21.9% in patients without antiviral prophylaxis, respectively. The logistic regression model indicated that for HBV reactivation, lack of antiviral prophylaxis (P=0.003) and tumor diameter (P=0.036) were independent risk factors. The OS and PFS were significantly shorter in the HBV reactivation group than the non-reactivation group (P=0.0023 and P=0.00073, respectively). The number of AEs was more in HBV reactivation group than the non-reactivation group, especially hepatic AEs.

Conclusion

HBV reactivation may occur in HCC patients treated with HAIC and lenvatinib plus PD1s. Patients with HBV reactivation had shorter survival time compared with non-reactivation. Therefore, HBV-related HCC patients should undergo antiviral therapy and HBV-DNA monitoring before and during the combination treatment.

GZ17-6.02 interacts with bexarotene to kill mycosis fungoides cells

GZ17-6.02, composed of curcumin, harmine and isovanillin, has undergone phase I evaluation in patients with solid tumors (NCT03775525) with an RP2D of 375 mg PO BID. The biology of GZ17-6.02 in malignant T cells and in particular those derived from mycosis fungoides (MF) patients, has not been studied. GZ17-6.02 alone and in combination with standard-of-care agents was effective in killing MF cells. All three components are necessary for optimal killing of MF cells. GZ17-6.02 activated ATM, the AMPK, NFκB and PERK and inactivated ERK1/2, AKT, ULK1, mTORC1, eIF2α, and reduced the expression of BCL-XL and MCL1. GZ17-6.02 increased ATG13 S318 phosphorylation and the expression of Beclin1, ATG5, BAK and BIM. GZ17-6.02 in a dose-dependent fashion enhanced autophagosome formation and autophagic flux, and tumor cell killing. Signaling by ATM and AMPK were both required for efficient killing but not for the dose-response effect whereas ER stress (eIF2α) and macroautophagy (Beclin1, ATG5) were required for both efficient killing and the dose-response. Knock down of the death receptor CD95 reduced killing by ~20% and interacted with autophagy inhibition to further reduce killing, collectively, by ~70%. Inhibition of autophagy and knock down of death-mediators downstream of the mitochondrion, AIF and caspase 3, almost abolished tumor cell killing. Hence in MF cells, GZ17-6.02 is a multi-factorial killer, utilizing ER stress, macroautophagy, death receptor signaling and directly causing mitochondrial dysfunction.

Impaired FADD/BID signaling mediates cross-resistance to immunotherapy in Multiple Myeloma

The treatment landscape in multiple myeloma (MM) is shifting from genotoxic drugs to immunotherapies. Monoclonal antibodies, immunoconjugates, T-cell engaging antibodies and CART cells have been incorporated into routine treatment algorithms, resulting in improved response rates. Nevertheless, patients continue to relapse and the underlying mechanisms of resistance remain poorly understood. While Impaired death receptor signaling has been reported to mediate resistance to CART in acute lymphoblastic leukemia, this mechanism yet remains to be elucidated in context of novel immunotherapies for MM. Here, we describe impaired death receptor signaling as a novel mechanism of resistance to T-cell mediated immunotherapies in MM. This resistance seems exclusive to novel immunotherapies while sensitivity to conventional anti-tumor therapies being preserved in vitro. As a proof of concept, we present a confirmatory clinical case indicating that the FADD/BID axis is required for meaningful responses to novel immunotherapies thus we report impaired death receptor signaling as a novel resistance mechanism to T-cell mediated immunotherapy in MM.

MAP kinase ERK5 modulates cancer cell sensitivity to extrinsic apoptosis induced by death-receptor agonists

Death receptor ligand TRAIL is a promising cancer therapy due to its ability to selectively trigger extrinsic apoptosis in cancer cells. However, TRAIL-based therapies in humans have shown limitations, mainly due inherent or acquired resistance of tumor cells. To address this issue, current efforts are focussed on dissecting the intracellular signaling pathways involved in resistance to TRAIL, to identify strategies that sensitize cancer cells to TRAIL-induced cytotoxicity. In this work, we describe the oncogenic MEK5-ERK5 pathway as a critical regulator of cancer cell resistance to the apoptosis induced by death receptor ligands. Using 2D and 3D cell cultures and transcriptomic analyses, we show that ERK5 controls the proteostasis of TP53INP2, a protein necessary for full activation of caspase-8 in response to TNFα, FasL or TRAIL. Mechanistically, ERK5 phosphorylates and induces ubiquitylation and proteasomal degradation of TP53INP2, resulting in cancer cell resistance to TRAIL. Concordantly, ERK5 inhibition or genetic deletion, by stabilizing TP53INP2, sensitizes cancer cells to the apoptosis induced by recombinant TRAIL and TRAIL/FasL expressed by Natural Killer cells. The MEK5-ERK5 pathway regulates cancer cell proliferation and survival, and ERK5 inhibitors have shown anticancer activity in preclinical models of solid tumors. Using endometrial cancer patient-derived xenograft organoids, we propose ERK5 inhibition as an effective strategy to sensitize cancer cells to TRAIL-based therapies.

Impacts of exposure to nanopolystyrene and/or chrysene at ambient concentrations on neurotoxicity in Siniperca chuatsi

Health risks caused by widespread environmental pollutants such as nanopolystyrene (NP) and chrysene (CHR) in aquatic ecosystems have aroused considerable concern. The present study established juvenile Mandarin fish (Siniperca chuatsi) models of NP and/or CHR exposure at ambient concentrations for 21 days to systematically investigate the underlying neurotoxicity mechanisms. The results showed that single and combined exposure to NP and CHR not only reduced the density of small neuronal cells in the grey matter layer of the optic tectum, but also induced brain oxidative stress according to physiological parameters including CAT, GSH-Px, SOD, T-AOC, and MDA. The co-exposure alleviated the histopathological damage, compared to NP and CHR single exposure group. These results indicate that NP and/or CHR causes neurotoxicity in S. chuatsi, in accordance with decreased acetylcholinesterase activity and altered expression of several marker genes of nervous system functions and development including c-fos, shha, elavl3, and mbpa. Transcriptomics analysis was performed to further investigate the potential molecular mechanisms of neurotoxicity. We propose that single NP and co-exposure induced oxidative stress activates MMP, which degrades tight junction proteins according to decreased expression of claudin, JAM, caveolin and TJP, ultimately damaging the integrity of the blood-brain barrier in S. chuatsi. Remarkably, the co-exposure exacerbated the blood-brain barrier disruption. More importantly, single NP and co-exposure induced neuronal apoptosis mainly activates the expression of apoptosis-related genes through the death receptor apoptosis pathway, while CHR acted through both death receptor apoptosis and endoplasmic reticulum apoptosis pathways. Additionally, subchronic CHR exposure caused neuroinflammation, supported by activation of TNF/NF-κB and JAK-STAT signaling pathways via targeting-related genes, while the co-exposure greatly alleviated the neuroinflammation. Collectively, our findings illuminate the underlying neurotoxicity molecular mechanisms of NP and/or CHR exposure on aquatic organisms.

Tetrandrine synergizes with MAPK inhibitors in treating KRAS-mutant pancreatic ductal adenocarcinoma via collaboratively modulating the TRAIL-death receptor axis

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal malignancies lacking effective therapies. KRAS mutations that occur in over 90% of PDAC are major oncogenic drivers of PDAC. The MAPK signaling pathway plays a central role in KRAS-driven oncogenic signaling. However, pharmacological inhibitors of the MAPK pathway are poorly responded in KRAS-mutant PDAC, raising a compelling need to understand the mechanism behind and to seek new therapeutic solutions. Herein, we perform a screen utilizing a library composed of 800 naturally-derived bioactive compounds to identify natural products that are able to sensitize KRAS-mutant PDAC cells to the MAPK inhibition. We discover that tetrandrine, a natural bisbenzylisoquinoline alkaloid, shows a synergistic effect with MAPK inhibitors in PDAC cells and xenograft models. Mechanistically, pharmacological inhibition of the MAPK pathway exhibits a double-edged impact on the TRAIL-death receptor axis, transcriptionally upregulating TRAIL yet downregulating its agonistic receptors DR4 and DR5, which may explain the limited therapeutic outcomes of MAPK inhibitors in KRAS-mutant PDAC. Of great interest, tetrandrine stabilizes DR4/DR5 protein via impairing ubiquitination-mediated protein degradation, thereby allowing a synergy with MAPK inhibition in inducing apoptosis in KRAS-mutant PDAC. Our findings identify a new combinatorial approach for treating KRAS-mutant PDAC and highlight the role of TRAIL-DR4/DR5 axis in dictating the therapeutic outcome in KRAS-mutant PDAC.

FAM84B promotes breast cancer tumorigenesis through activation of the NF-κB and death receptor signaling pathways

Breast cancer (BC) occurs predominantly in women and leads to numerous deaths every year. The identification of effective therapeutic targets will benefit BC patients and increase the likelihood of finding a cure. Family with similar sequence 84, member B (FAM84B) has been implicated in the progression of many kinds of cancers, but its function in BC remains to be explored. In this study, online database analysis revealed that FAM84B expression was higher in BC patient tissues, especially in luminal BC tissues, than in the corresponding normal tissues; furthermore, increased FAM84B expression was related to poor prognosis. Additionally, western blot (WB) analysis revealed that the FAM84B protein was highly expressed in luminal BC cell lines compared to normal and basal-like BC cell lines. Moreover, clinical BC patient tissues were collected and subjected to WB and immunohistochemical (IHC) analyses, and the results showed that FAM84B was expressed mainly in luminal BC samples. Therefore, to determine the function of FAM84B in luminal BC cells, luminal BC cell lines with FAM84B knockout and overexpression were generated. In addition, the functions of FAM84B were evaluated in vitro (via cell proliferation, wound healing, colony formation and invasion assays) and in vivo (via a subcutaneous xenograft experiment), and the results showed that FAM84B regulated cell proliferation but not cell invasion. Furthermore, the results of RNA sequencing analysis in ZR-75-1 FAM84B knockout and FAM84B-overexpressing cells showed that FAM84B could affect the TNF signaling pathway. Subsequently, WB analysis of death receptor signaling and immunofluorescence (IF) analysis of NF-κB p65 localization revealed that FAM84B affected death receptor signaling and promoted NF-κB p65 nuclear entry. In conclusion, we found that FAM84B promotes luminal BC tumorigenesis through the activation of the NF-κB and death receptor signaling pathways.

Pressure-Enabled Drug Delivery (PEDD) of a class C TLR9 agonist in combination with checkpoint inhibitor therapy in a murine pancreatic cancer model

BACKGROUND

Systemic immunotherapy has had limited clinical benefit in pancreatic ductal adenocarcinoma. This is thought to be due to its desmoplastic immunosuppressive tumor microenvironment in addition to high intratumoral pressures that limit drug delivery. Recent preclinical cancer models and early-phase clinical trials have demonstrated the potential of toll-like receptor 9 agonists, including the synthetic CpG oligonucleotide SD-101, to stimulate a wide range of immune cells and eliminate suppressive myeloid cells. We hypothesized that Pressure-Enabled Drug Delivery via Pancreatic Retrograde Venous Infusion of toll-like receptor 9 agonist would improve responsiveness to systemic anti-programmed death receptor-1 checkpoint inhibitor therapy in a murine orthotopic pancreatic ductal adenocarcinoma model.

METHODS

Murine pancreatic ductal adenocarcinoma (KPC4580P) tumors were implanted into the pancreatic tails of C57BL/6J mice and treated 8 days after implantation. Mice were assigned to one of the following treatment groups: Pancreatic Retrograde Venous Infusion delivery of saline, Pancreatic Retrograde Venous Infusion delivery of toll-like receptor 9 agonist, systemic anti-programmed death receptor-1, systemic toll-like receptor 9 agonist, or the combination of Pancreatic Retrograde Venous Infusion delivery of toll-like receptor 9 agonist and systemic anti-programmed death receptor-1 (Combo). Fluorescently labeled toll-like receptor 9 agonist (radiant efficiency) was used to measure uptake of the drug on day 1. Changes in tumor burden were evaluated by necropsy at 2 different time points, 7 and 10 days after toll-like receptor 9 agonist treatment. Blood and tumors were collected at necropsy 10 days after toll-like receptor 9 agonist treatment for flow cytometric analysis of tumor-infiltrating leukocytes and plasma cytokines.

RESULTS

All mice analyzed survived to necropsy. Site of tumor fluorescence measurements revealed 3-fold higher intensity fluorescence in Pancreatic Retrograde Venous Infusion delivery of toll-like receptor 9 agonist compared to systemic toll-like receptor 9 agonist mice. Tumor weights were significantly lower in the Combo group compared to Pancreatic Retrograde Venous Infusion delivery of saline. Flow cytometry of the Combo group demonstrated significantly increased overall T-cell number, specifically CD4+ T-cells, and a trend toward increased CD8+ T-cells. Cytokine analysis showed significantly decreased IL-6 and CXCL1.

CONCLUSION

Pressure-Enabled Drug Delivery of toll-like receptor 9 agonist by Pancreatic Retrograde Venous Infusion with systemic anti-programmed death receptor-1 demonstrated improved pancreatic ductal adenocarcinoma tumor control in a murine pancreatic ductal adenocarcinoma model. These results support study of this combination therapy in pancreatic ductal adenocarcinoma patients and expansion of ongoing Pressure-Enabled Drug Delivery clinical trials.

Molecular dissection of anti-colon cancer activity of NARI-29: special focus on H2O2 modulated NF-κB and death receptor signaling

Accumulating evidence attributes the role of aldose reductase (AR) in modulating ROS and inflammation which are the main factor responsible for cancer progression and drug resistance. Epalrestat is the only AR inhibitor being used in Asian countries. It did not make it to the markets of the USA and Europe due to marginal efficacy as an antioxidant and anti-inflammatory agent owing to difficulty reaching intracellular targets. In our previous studies, we attempted to synthesize the epalrestat analogs and reported that the compound 4-((Z)-5-((Z)-2-Cyano-3-phenylallylidene)-4-oxo-2-thioxothiazolidin-3-yl) benzoic acid named as NARI-29 has potent AR inhibition compared to epalrestat. In the current study, we aimed to find the effect of NARI-29 on ROS-induced cancer progression and TRAIL resistance in colon cancer in vitro models. In the first part of the study, we demonstrated that the NARI-29 has specific AKR1B1 inhibition and superior drug-like properties than epalrestat using bioinformatics tools. In the second part of the study, it was proven that NARI-29 has induced the hydrogen peroxide-triggered TRAIL-induced apoptosis in the colon cancer cells via modulating the AKR1B1/4HNE/FOXO3a/DR axis. The selective cytotoxicity of NARI-29 (10-fold) compared to epalrestat (4-fold) toward cancer cells is due to its differential ROS regulation and anti-inflammatory activities. Altogether, these data show that NARI-29 may be a potential candidate for AR inhibitors, which will be used to prevent colon cancer progression and as adjuvant therapy for preventing TRAIL resistance.

Targeting multifunctional magnetic nanowires for drug delivery in cancer cell death: an emerging paradigm

Apoptosis, often known as programmed cell death is a mechanism used by numerous species to maintain tissue homeostasis. The process leading to cell death is complicated because it requires the stimulation of caspases. According to several studies, nanowires have important medical benefits, can kill cells by adhering to cancer cells, destroying them, and killing the entire cell using a triple attack that integrates vibration, heat, and drug delivery to trigger apoptosis. The sewage effluents and industrial, fertilizer and organic wastes decomposition can produce elevated levels of chemicals in the environment which may interrupt the cell cycle and activate apoptosis. The purpose of this review is to give a thorough summary of the evidence that is currently available on apoptosis. Current review discussed topics like the morphological and biochemical alterations that occur during apoptosis, as well as the various mechanisms that cause cell death, including the intrinsic (or mitochondrial), extrinsic (or death receptor), and intrinsic endoplasmic reticulum pathway. The apoptosis reduction in cancer development is mediated by (i) an imbalance between pro- and anti-apoptotic proteins, such as members of the B-cell lymphoma-2 (BCL2) family of proteins, tumour protein 53 and inhibitor of apoptosis proteins, (ii) a reduction in caspase activity, and (iii) impaired death receptor signalling. This review does an excellent task of outlining the function of nanowires in both apoptosis induction and targeted drug delivery for cancer cells. A comprehensive summary of the relevance of nanowires synthesised for the purpose of inducing apoptosis in cancer cells has been compiled collectively.

Clinical outcomes of lenvatinib plus transarterial chemoembolization with or without programmed death receptor-1 inhibitors in unresectable hepatocellular carcinoma

BACKGROUND

Programmed death receptor-1 (PD-1) inhibitors have been approved as second-line treatment regimen in hepatocellular carcinoma (HCC), but it is still worth studying whether patients can benefit from PD-1 inhibitors as first-line drugs combined with targeted drugs and locoregional therapy.

AIM

To estimate the clinical outcome of transarterial chemoembolization (TACE) and lenvatinib plus PD-1 inhibitors for patients with unresectable HCC (uHCC).

METHODS

We carried out retrospective research of 65 patients with uHCC who were treated at Peking Union Medical College Hospital from September 2017 to February 2022. 45 patients received the PD-1 inhibitors, lenvatinib, TACE (PD-1-Lenv-T) therapy, and 20 received the lenvatinib, TACE (Lenv-T) therapy. In terms of the dose of lenvatinib, 8 mg was given orally for patients weighing less than 60 kg and 12 mg for those weighing more than 60 kg. Of the patients in the PD-1 inhibitor combination group, 15 received Toripalimab, 14 received Toripalimab, 14 received Camrelizumab, 4 received Pembrolizumab, 9 received Sintilimab, and 2 received Nivolumab, 1 with Tislelizumab. According to the investigators’ assessment, TACE was performed every 4-6 wk when the patient had good hepatic function (Child-Pugh class A or B) until disease progression occurred. We evaluated the efficacy by the modified Response Evaluation Criteria in Solid Tumors (mRECIST criteria). We accessd the safety by the National Cancer Institute Common Terminology Criteria for Adverse Events, v 5.0. The key adverse events (AEs) after the initiation of combination therapy were observed.

RESULTS

Patients with uHCC who received PD-1-Lenv-T therapy (n = 45) had a clearly longer overall survival than those who underwent Lenv-T therapy (n = 20, 26.8 vs 14.0 mo; P = 0.027). The median progression-free survival time between the two treatment regimens was also measured {11.7 mo [95% confidence interval (CI): 7.7-15.7] in the PD-1-Lenv-T group vs 8.5 mo (95%CI: 3.0-13.9) in the Lenv-T group (P = 0.028)}. The objective response rates of the PD-1-Lenv-T group and Lenv-T group were 44.4% and 20% (P = 0.059) according to the mRECIST criteria, meanwhile the disease control rates were 93.3% and 64.0% (P = 0.003), respectively. The type and frequency of AEs showed little distinction between patients received the two treatment regimens.

CONCLUSION

Our results suggest that the early combination of PD-1 inhibitors has manageable toxicity and hopeful efficacy in patients with uHCC.

HPV upregulates MARCHF8 ubiquitin ligase and inhibits apoptosis by degrading the death receptors in head and neck cancer

The membrane-associated RING-CH-type finger ubiquitin ligase MARCHF8 is a human homolog of the viral ubiquitin ligases Kaposi's sarcoma herpesvirus K3 and K5 that promote host immune evasion. Previous studies have shown that MARCHF8 ubiquitinates several immune receptors, such as the major histocompatibility complex II and CD86. While human papillomavirus (HPV) does not encode any ubiquitin ligase, the viral oncoproteins E6 and E7 are known to regulate host ubiquitin ligases. Here, we report that MARCHF8 expression is upregulated in HPV-positive head and neck cancer (HNC) patients but not in HPV-negative HNC patients compared to normal individuals. The MARCHF8 promoter is highly activated by HPV oncoprotein E6-induced MYC/MAX transcriptional activation. The knockdown of MARCHF8 expression in human HPV-positive HNC cells restores cell surface expression of the tumor necrosis factor receptor superfamily (TNFRSF) death receptors, FAS, TRAIL-R1, and TRAIL-R2, and enhances apoptosis. MARCHF8 protein directly interacts with and ubiquitinates the TNFRSF death receptors. Further, MARCHF8 knockout in mouse oral cancer cells expressing HPV16 E6 and E7 augments cancer cell apoptosis and suppresses tumor growth in vivo. Our findings suggest that HPV inhibits host cell apoptosis by upregulating MARCHF8 and degrading TNFRSF death receptors in HPV-positive HNC cells.

In vivo and in vitro study on hepatotoxicity of Tris-(2, 3-dibromopropyl) isocyanurate exposure via mitochondrial and death receptor pathway

Tri-(2,3-dibromopropyl) isocyanate (TBC), a newly brominated flame retardant, is widely used in the synthesis of flame retardant materials with characteristics of persistent organic pollutants. To obtain environmental exposure risks of TBC, Wistar rats and HepG2 cell were used for in vivo and in vitro studies on the toxicity of TBC and relevant ecotoxicological mechanisms of apoptosis. 80 Wistar rats were randomly selected and divided into four exposure groups (0, 0.313, 0.625, 1.250) g/(kg·bw) TBC, half male and half female, with oral administration for 28 days. Wistar rats exhibited appetite loss, weight loss, and dull hair with increasing period of TBC exposure. The pathological examinations revealed the most severe damage of liver and the ratio of liver/body weight of 35.497 × 10^-3 for high-dosed group (1.250 g/kg·bw) was higher than that of 32.792 × 10^-3 for control group in female rats with identical trend in male rats. The above indicators was fairly consistent with the serum test results which further confirmed the liver to be the target organ. The exposure dosages of HepG2 cell were (0, 12.5, 25, 50) μg/mL, individually. The HepG2 cells exposed to TBC for 72 h displayed hazy cell contour and decreased density of cell growth. And there was an inhibition detected by MTT assay, where the maximum inhibition rate was 19.93% under the dose of 50 μg/mL TBC. Apoptosis rate detected by flow cytometry which was demonstrated to be positively correlated to exposure dosage of TBC. The apoptosis rates of the low, medium and high dose groups of TBC exposure were (1.082 ± 0.109) %, (3.017 ± 0.09) % and (6.813 ± 0.233) %, individually. Targeted genes and corresponding protein expressions that triggering apoptosis both in vivo and in vitro were significantly altered. Overall, this work discloses the impacts of TBC exposure on hepatotoxicity, which provides new insights for chemical risk assessments of accelerate cell apoptosis via mitochondrial and death receptor pathway.

Cocktail Effect of Endocrine Disrupting Chemicals: Application to Chlorpyrifos in Lavender Essential Oils

Chlorpyrifos is a pesticide that is toxic to human health and has been banned for the past decade. Due to its persistent and bioaccumulative properties, chlorpyrifos is still present in soil. Pregnant women can be exposed to chlorpyrifos through drinking water and herbal products, such as essential oils (EOs), resulting in adverse effects to the mother and fetus. Our objective was to evaluate and compare the potential endocrine disrupting effects of chlorpyrifos "free" or in contaminated lavender EO. We studied the release of four hormones and the activation of the P2X7 cell death receptor in human placental JEG-Tox cells as key biomarkers of endocrine toxicity for pregnant women (hPlacentox assay). We observed that "free" chlorpyrifos disrupted placental hormones and activated the P2X7 receptor, whereas chlorpyrifos in lavender EO disrupted only the placental hormones. We confirm that chlorpyrifos can be classified as an endocrine disrupting chemical (EDC) for pregnant women and point out that its endocrine disrupting effect may not be apparent when present in lavender EOs. Our results reveal the existence of specific reverse cocktail effects that may have protective properties against EDCs.

High blood Fas concentrations in non-survivor patients with traumatic brain injury

Fas is one of the main death receptors of the extrinsic pathway of apoptosis. A study has reported higher Fas expression in brain samples of non-surviving TBI patients than in survivors. The objective of our current study was to determine whether there is an association between Fas concentrations in blood and mortality of isolated TBI patients. Patients with severe TBI [< 9 points in Glasgow Coma Scale (GCS)] and isolated TBI (< 10 non-cranial aspects points on the Injury Severity Score) were included from 5 Intensive Care Units. We measured serum Fas concentrations on the day of TBI. Non-surviving (n = 23) compared to surviving patients (n = 57) had higher age (p = 0.01), lower GCS (p = 0.001), higher APACHE-II score (p < 0.001), higher ICP (p = 0.01), higher CT findings with high risk of death (p = 0.02) and higher serum Fas concentrations (p < 0.001). We found in regression analyses an association between serum Fas levels and mortality of TBI patients after controlling for CT findings, age and CGS (OR = 1.006; 95% CI 1.001-1.011; p = 0.02), and after controlling for CT findings, ICP and APACHE-II (OR = 1.007; 95% CI 1.001-1.012; p = 0.02). Thus, the most interesting and novel finding in this study is the association between high blood Fas concentrations and mortality in TBI patients.

Combined nivolumab and ipilimumab with or without stereotactic body radiation therapy for advanced Merkel cell carcinoma: a randomised, open label, phase 2 trial

BACKGROUND

Merkel cell carcinoma is among the most aggressive and lethal of primary skin cancers, with a high rate of distant metastasis. Anti-programmed death receptor 1 (anti-PD-1) and programmed death ligand 1 (PD-L1) monotherapy is currently standard of care for unresectable, recurrent, or metastatic Merkel cell carcinoma. We assessed treatment with combined nivolumab plus ipilimumab, with or without stereotactic body radiotherapy (SBRT) in patients with advanced Merkel cell carcinoma as a first-line therapy or following previous treatment with anti-PD-1 and PD-L1 monotherapy.

METHODS

In this randomised, open label, phase 2 trial, we randomly assigned adults from two cancer sites in the USA (one in Florida and one in Ohio) to group A (combined nivolumab and ipilimumab) or group B (combined nivolumab and ipilimumab plus SBRT) in a 1:1 ratio. Eligible patients were aged at least 18 years with histologically proven advanced stage (unresectable, recurrent, or stage IV) Merkel cell carcinoma, a minimum of two tumour lesions measureable by CT, MRI or clinical exam, and tumour tissue available for exploratory biomarker analysis. Patients were stratified by previous immune-checkpoint inhibitor (ICI) status to receive nivolumab 240 mg intravenously every 2 weeks plus ipilimumab 1 mg/kg intravenously every 6 weeks (group A) or the same schedule of combined nivolumab and ipilimumab with the addition of SBRT to at least one tumour site (24 Gy in three fractions at week 2; group B). Patients had to have at least two measurable sites of disease so one non-irradiated site could be followed for response. The primary endpoint was objective response rate (ORR) in all randomly assigned patients who received at least one dose of combined nivolumab and ipilimumab. ORR was defined as the proportion of patients with a complete response or partial response per immune-related Response Evaluation Criteria in Solid Tumours. Response was assessed every 12 weeks. Safety was assessed in all patients. This trial is registered with ClinicalTrials.gov, NCT03071406.

FINDINGS

50 patients (25 in both group A and group B) were enrolled between March 14, 2017, and Dec 21, 2021, including 24 ICI-naive patients (13 [52%] of 25 group A patients and 11 [44%] of 25 group B patients]) and 26 patients with previous ICI (12 [48%] of 25 group A patients and 14 [56%] of 25 group B patients]). One patient in group B did not receive SBRT due to concerns about excess toxicity. Median follow-up was 14·6 months (IQR 9·1-26·5). Two patients in group B were excluded from the analysis of the primary endpoint because the target lesions were irradiated and so the patients were deemed non-evaluable. Of the ICI-naive patients, 22 (100%) of 22 (95% CI 82-100) had an objective response, including nine (41% [95% CI 21-63]) with complete response. Of the patients who had previously had ICI exposure, eight (31%) of 26 patients (95% CI 15-52) had an objective response and four (15% [5-36]) had a complete response. No significant differences in ORR were observed between groups A (18 [72%] of 25 patients) and B (12 [52%] of 23 patients; p=0·26). Grade 3 or 4 treatment-related adverse events were observed in 10 (40%) of 25 patients in group A and 8 (32%) of 25 patients in group B.

INTERPRETATION

First-line combined nivolumab and ipilimumab in patients with advanced Merkel cell carcinoma showed a high ORR with durable responses and an expected safety profile. Combined nivolumab and ipilimumab also showed clinical benefit in patients with previous anti-PD-1 and PD-L1 treatment. Addition of SBRT did not improve efficacy of combined nivolumab and ipilimumab. The combination of nivolumab and ipilimumab represents a new first-line and salvage therapeutic option for advanced Merkel cell carcinoma.

FUNDING

Bristol Myers Squibb Rare Population Malignancy Program.

Examination of the role of necroptotic damage-associated molecular patterns in tissue fibrosis

Fibrosis is defined as the abnormal and excessive deposition of extracellular matrix (ECM) components, which leads to tissue or organ dysfunction and failure. However, the pathological mechanisms underlying fibrosis remain unclear. The inflammatory response induced by tissue injury is closely associated with tissue fibrosis. Recently, an increasing number of studies have linked necroptosis to inflammation and fibrosis. Necroptosis is a type of preprogrammed death caused by death receptors, interferons, Toll-like receptors, intracellular RNA and DNA sensors, and other mediators. These activate receptor-interacting protein kinase (RIPK) 1, which recruits and phosphorylates RIPK3. RIPK3 then phosphorylates a mixed lineage kinase domain-like protein and causes its oligomerization, leading to rapid plasma membrane permeabilization, the release of cellular contents, and exposure of damage-associated molecular patterns (DAMPs). DAMPs, as inflammatory mediators, are involved in the loss of balance between extensive inflammation and tissue regeneration, leading to remodeling, the hallmark of fibrosis. In this review, we discuss the role of necroptotic DAMPs in tissue fibrosis and highlight the inflammatory responses induced by DAMPs in tissue ECM remodeling. By summarizing the existing literature on this topic, we underscore the gaps in the current research, providing a framework for future investigations into the relationship among necroptosis, DAMPs, and fibrosis, as well as a reference for later transformation into clinical treatment.

Esophagogastric Cancers: Integrating Immunotherapy Therapy Into Current Practice

Immunotherapy (IO) agents have led to significant improvements in patient outcomes across many tumor types. There have been great efforts to introduce immune checkpoint inhibitors into the treatment paradigm of esophagogastric cancers as well. A number of randomized phase III trials, which will be reviewed here, established the role of these agents in both early-stage and advanced-stage disease. Adjuvant nivolumab is US Food and Drug Administration-approved after neoadjuvant chemoradiation and resection of esophageal and gastroesophageal junction cancers on the basis of the phase III CheckMate 577 trial. In the advanced setting, patients with programmed death receptor ligand-1-positive tumors should be recommended IO in combination with chemotherapy in the first-line setting on the basis of the results from KEYNOTE 590, CheckMate 649, and CheckMate 648. Across trials, chemotherapy continues to play a critical role in the first-line setting and should be offered to all patients who are eligible for systemic therapy, including those with biomarker select tumors. In the later lines of treatment, IO has modest activity, and prior studies have grown largely irrelevant because of the enrollment of IO-naive patients. Similar to other disease types, patients with microsatellite unstable (microsatellite instability high) tumors represent a unique cohort that is more sensitive to IO. However, there are no randomized studies evaluating how best to apply IO in early or advanced stages specifically for the treatment of patients with microsatellite instability high upper GI tumors. Questions remain how to best select patients who benefit from IO treatments, how to augment IO activity in programmed death receptor ligand-1-negative tumors, and how to incorporate IO in late-line settings or for recurrent disease that has been treated with IO-containing regimens during early stages.

Death receptor-dependent apoptosis and cell cycle delay induced by bioymifi in human cervical cancer cells

In chemotherapy applied against cervical cancer, non-specific cytotoxicity and drug resistance that develops over time are trying to be overcome. Therefore, the development of effective and innovative chemotherapeutic drugs for the treatment is among the priority issues in the medical field. The anticancer activity of the Bioymifi, which can activate apoptosis by inducing DR-5 clustering and aggregation against the human cervical cancer cell line, was investigated in the current study. The cytotoxic activity of Bioymifi on the HeLa cell line was identified using XTT assay. The pathway of the cell death mechanism was analyzed through the cell cycle and Annexin V assays by the flow cytometry. DAPI staining assay was applied under fluorescence microscopy to examine the nuclear morphology. Bioymifi appeared to have a remarkable IC₅₀ value (11.75μM) against HeLa cells. The cell cycle analysis demonstrated the increase of Bioymifi cured HeLa cells in the S phase. And also, 11.75µM of Bioymifi caused a significantly higher apoptotic effect compared to control. In addition, in vitro immunofluorescence experiments of this study represented that Bioymifi reduced Ki-67 localization in HeLa cells. Bioymifi has significantly anticancer actions in Human cervix cancer in vitro and can be combined with standard treatment.

Fusobacterium necrophorum Promotes Apoptosis and Inflammatory Cytokine Production Through the Activation of NF-κB and Death Receptor Signaling Pathways

Fusobacterium necrophorum can cause liver abscess, foot rot in ruminants, and Lemire syndrome in humans, Also, its virulence factors can induce the apoptosis of macrophages and neutrophils. However, the detailed mechanism has not been fully clarified. This study investigated the mechanisms of apoptosis and inflammatory factor production in F. necrophorum–induced neutrophils and macrophages (RAW246.7). After infection of macrophages with F. necrophorum, 5-ethynyl-2’-deoxyuridine labeling assays indicated that F. necrophorum inhibited macrophage proliferation in a time- and dose-dependent manner. Hoechst staining and DNA ladder assays showed significant condensation of the nucleus and fragmentation of genomic DNA in F. necrophorum–infected macrophages, Annexin V (FITC) and propidium iodide (PI) assay confirmed the emergence of apoptosis in the macrophages and sheep neutrophils with F. necrophorum compared with the control. The group with significant apoptosis was subjected to RNA sequencing (RNA-Seq), and the sequencing results revealed 2581 up– and 2907 downregulated genes. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of the differentially expressed genes showed that F. necrophorum drove apoptosis and production of inflammatory factors by activating genes related to the Nuclear Factor-κB (NF-κB) and death receptor pathways. Meanwhile, quantitative reverse transcription PCR and Western blot validation results were consistent with the results of transcriptome sequencing analysis. In conclusion, F. necrophorum induced apoptosis and production of pro-inflammatory factors through the NF-κB and death receptor signaling pathway, providing a theoretical basis for further mechanistic studies on the prevention and control of F. necrophorum disease treatment.

Extranodal NK/T-cell lymphoma: a case report of renal insufficiency during PD1 inhibitor treatment

BACKGROUND

Extranodal NK/T-cell lymphoma (ENKTL) is a subtype of non-Hodgkin's lymphoma that accounts for approximately 3-8% of all malignant lymphomas. So far, ENKTL has no standard treatment guidelines, and the current treatment methods pose adverse effects. The combination of programmed death receptors (PD-1) and programmed death receptors' ligands (PD-L1) downregulates effector T cells; hence, it may be an effective treatment for NK/T-cell lymphoma. Here, we report a patient diagnosed with ENKTL whose health was significantly improved after PD-1 immunotherapy. At the same time, the patient suffered from related renal toxic side effects. Immunotherapy is an emerging treatment method for tumors, and the early diagnosis and identification of its side effects are vital for the diagnosis and treatment of tumors.

CASE REPORT

Laboratory tests, pathological examinations, and the patient's history were performed to estimate the severity and the cause of renal insufficiency. The patient with ENKTL developed transient renal damage during immunotherapy. During the next treatment and examination, renal insufficiency was irrelevant to PD-1 inhibitors and avoided unnecessary drug withdrawal.

CONCLUSIONS

In the present case report, we discuss a patient who developed a severe transient renal impairment during immunotherapy and review published studies regarding immunotherapy and its renal-related side effects. We also outline how to critically distinguish whether a patient's kidney injury is anti-PD-1 treatment. We also provide insights to oncologists to develop an effective follow-up treatment plan for early detection and management of any anti-PD-1 treatment side effects.

Efficacy and Safety of PD-1/PD-L1 Inhibitor Chemotherapy Combined with Lung Cancer Fang No. 1 in Relapsed and Refractory SCLC: A Retrospective Observational Study

Background

Relapsed and refractory small cell lung cancer (SCLC) accounts for about 15% of all lung cancers. The prognosis of patients is poor. The 5-year survival rate is almost 0. The average survival time of patients who refuse to receive treatment is only 2-4 months. For patients with extensive-stage SCLC, the current first-line treatment regimens are mainly platinum-containing double-drug chemotherapy. Poside combined with cisplatin/carboplatin and irinotecan combined with cisplatin/carboplatin are commonly used clinical regimens for the treatment of patients with extensive-stage SCLC. Although SCLC is very sensitive to radiotherapy and chemotherapy, most patients will develop recurrence and metastasis after initial treatment. Therefore, it is necessary to study clinically effective therapeutic drugs for relapsed and refractory SCLC.

Objective

To investigate the relationship between programmed death receptor-1 (programmed death receptor-1 (PD-1)) and programmed death receptor-ligand 1 (programmed death-ligand 1 (PD-L1)) inhibitors and Lung Cancer No. 1 efficacy and safety of Lung Cancer Fang No. 1 in the treatment of relapsed and refractory SCLC.

Methods

80 patients with refractory SCLC were selected and randomly divided into control group and treatment group with 40 cases in each group. Among them, the control group received PD-1/PD-L1 inhibitor chemotherapy, and the treatment group received PD-1/PD-L1 inhibitor chemotherapy combined with Lung Cancer Fang No. 1 treatment. The differences in immune and tumor marker levels, clinical efficacy, and prognostic complications between the two groups before and after treatment were observed and compared.

Results

Before treatment, there was no significant difference in clinical improvement between the two groups. After treatment, the clinical symptom scores and body weight changes in the treatment group were significantly improved. The clinical symptom scores in the treatment group were lower than those in the control group, but the body weight changes were higher than those in the control group. The difference was statistically significant (P < 0.05). Before treatment, there was no significant difference in the levels of tumor markers between the two groups. After treatment, the levels of CYFRA21-1, CA125, and VGEF in the treatment group were significantly lower than those in the control group, and the difference was statistically significant (P < 0.05). There was no significant difference in the immune level between the two groups before treatment (P > 0.05), while the differences in CD4+, CD3+, and CD4+/CD8+ after treatment were significant, and the treatment group was higher than the control group, with statistical significance (P < 0.05). After treatment, the clinical efficacy of the two groups was significantly improved. The DCR90.00% of the treatment group was significantly higher than that of the control group, 67.50%, and the difference was statistically significant (P < 0.05). The analysis of complications after treatment showed that fatigue, anorexia, hypertension, hand-foot syndrome, diarrhea, leukopenia, thrombocytopenia, and urinary protein in the treatment group were significantly lower than those in the control group, and the difference was statistically significant (P < 0.05).

Conclusion

PD-1/PD-L1 inhibitor chemotherapy combined with Lung Cancer Fang No. 1 has a good and safe effect on SCLC patients. It has a good curative effect in improving the clinical symptoms of patients. It can stabilize the tumor, inhibit the development of lung cancer, improve the body's cellular immune function, adjust the level and expression of tumor markers, improve the body's material metabolism, and restore the balance of yin and yang in the body.

Inhibitors of ERp44, PDIA1, and AGR2 induce disulfide-mediated oligomerization of Death Receptors 4 and 5 and cancer cell death

Breast cancer mortality remains unacceptably high, indicating a need for safer and more effective therapeutic agents. Disulfide bond Disrupting Agents (DDAs) were previously identified as a novel class of anticancer compounds that selectively kill cancers that overexpress the Epidermal Growth Factor Receptor (EGFR) or its family member HER2. DDAs kill EGFR+ and HER2+ cancer cells via the parallel downregulation of EGFR, HER2, and HER3 and activation/oligomerization of Death Receptors 4 and 5 (DR4/5). However, the mechanisms by which DDAs mediate these effects are unknown. Affinity purification analyses employing biotinylated-DDAs reveal that the Protein Disulfide Isomerase (PDI) family members AGR2, PDIA1, and ERp44 are DDA target proteins. Further analyses demonstrate that shRNA-mediated knockdown of AGR2 and ERp44, or expression of ERp44 mutants, enhance basal DR5 oligomerization. DDA treatment of breast cancer cells disrupts PDIA1 and ERp44 mixed disulfide bonds with their client proteins. Together, the results herein reveal DDAs as the first small molecule, active site inhibitors of AGR2 and ERp44, and demonstrate roles for AGR2 and ERp44 in regulating the activity, stability, and localization of DR4 and DR5, and activation of Caspase 8.

Tislelizumab: A Modified Anti-tumor Programmed Death Receptor 1 Antibody

Tislelizumab is an anti-programmed death receptor 1 (PD-1) monoclonal immunoglobulin G 4 antibody developed by BeiGene. The structure of tislelizumab has been modified to maximally inhibit the binding of PD-1 to programmed death ligand 1 (PD-L1) and minimize the binding of tislelizumab to Fcγ receptors. In clinical studies, tislelizumab has shown preliminary anti-tumor effects in various solid tumors, such as Hodgkin's lymphoma, urothelial carcinoma, lung cancer, gastric and esophageal cancer, liver cancer, nasopharyngeal carcinoma, colorectal cancer, and microsatellite instability-high/mismatch repair-deficient tumors. In addition, it also showed new promise in solid tumor treatment in combination with ociperlimab. Due to its satisfactory anti-tumor effects, tislelizumab has received approvals in China for the treatment of classical Hodgkin's lymphoma, urothelial carcinoma, squamous non-small cell lung cancer, non-squamous non-small cell lung cancer, and hepatocellular carcinoma, and it is now under investigation for a new indication in microsatellite instability-high/mismatch repair-deficient tumors. Moreover, it has been granted orphan designations in hepatocellular carcinoma, esophageal cancer, and gastric cancer, including cancer of the gastroesophageal junction, by the US Food and Drug Administration. Tislelizumab has an acceptable safety profile; the most common adverse effects include fatigue, anemia, and decreased neutrophil count, while the most fatal events have been related to respiratory infection or failure, and hepatic injury. Tislelizumab has an economic advantage compared with other well-studied PD-1/PD-L1 inhibitors; thus, the introduction of it could provide clinical oncologists with an effective weapon against tumors and may alleviate the burden of cancer patients.

Hepatitis B virus infection does not affect the clinical outcome of anti-programmed death receptor-1 therapy in advanced solid malignancies: Real-world evidence from a retrospective study using propensity score matching

This study aimed to investigate the impact of hepatitis B virus (HBV) infection on the outcome of patients with advanced solid malignancies treated with programmed death receptor-1 (PD-1) inhibitors.We retrospectively included patients treated with PD-1 inhibitors between August 2018 and April 2020. Propensity score matching (PSM) was performed to match the characteristics of the HBV and non-HBV groups. Objective response rate (ORR) and disease control rate (DCR) were compared between HBV and non-HBV groups using χ2 or Fisher exact tests. Kaplan-Meier and log-rank tests were used to analyze overall survival (OS) and progression-free survival (PFS).A total of 120 patients, including 43 (35.8%) with HBV and 77 (64.2%) without HBV, were enrolled. Cases of HBV reactivation were not observed. In the entire study population, ORR and DCR did not significantly differ between both groups. After PSM, the study population comprised 39 patients, 15 with and 24 without HBV. The HBV group had an ORR of 55.6%, whereas the ORR in the non-HBV group was 36.8% (P = .35). Similarly, the DCR was 77.8% in the HBV group, as compared to 68.4% in the non-HBV group (P  = .61). Additionally, HBV infection did not significantly affect OS (P  = .54) and PFS (P  = .64) in the unmatched cohort. Moreover, statistically significant differences regarding OS (P  = .15) and PFS (P  = .23) were also not detected after PSM.In conclusion, the HBV infection status did not impact the therapy response or prognosis of patients treated with PD-1 inhibitors. Further prospective studies are needed to corroborate these findings.

Tannic acid repair of zearalenone-induced damage by regulating the death receptor and mitochondrial apoptosis signaling pathway in mice

Zearalenone (ZEA) is an estrogenic toxin produced by Fusarium strains, that is widely present in crops, and endangers the reproductive system of animals. Tannic acid (TA) is a natural polyphenolic substance that is widespread in the roots, stems, and leaves of plants, and has special pharmacological activity. This study was designed to investigate the therapeutic effect of TA on ZEA-induced ovarian damage in mice and to explore the molecular mechanism involved. Ninety healthy Kunming female mice were divided into six equal groups. All the groups but the control group were administered daily with ZEA [10 mg/kg body weight (bw)] orally, for 7 days, to induce damage to the reproductive system. Some groups were also administered with TA (50, 100, and 200 mg/bw) for 7 days. Mice were euthanized 24 h later to allow for collection of serum and ovaries. TA can effectively alleviate the appearance of congestion and redness of the ovary, caused by ZEA, and increase the number of healthy growing follicles. Moreover, the estrogen content and the levels of MDA and ROS in the ovaries can be effectively reduced by TA. It can also reduce the apoptosis of ovarian cells, decreases the protein expression of the estrogen receptor, Fas, Fasl, caspase-3, caspase-8, caspase-9, and Bax, and increases the protein expression of Bcl-2. Our study indicates that TA reduces the strong estrogen and oxidative damage induced by ZEA, and these therapeutic effects may be partially mediated by the death receptor and mitochondrial apoptosis signaling pathway.

The red blood cell death receptor and thrombosis

RBCs are the most abundant circulating cells in humans and typically comprise 35% to 45% of the blood volume (hematocrit). Anemia is associated with an increase in bleeding, and epidemiological studies have shown an association between an elevated hematocrit and thrombosis. RBCs may contribute to hemostasis and thrombosis via mechanisms that include platelet margination leading to an increase in the near-wall platelet concentration, blood viscosity, thrombin generation, and platelet activation. In this issue of the JCI, Klatt et al. report that binding of the Fas ligand FasL on the surface of platelets to its cognate receptor FasR on the surface of RBCs increases thrombin generation in vitro and thrombosis in mouse models. This represents a new mechanism by which RBCs contribute to thrombosis.

Mono(2-ethylhexyl) phthalate induces apoptosis in p53-silenced L02 cells via activation of both mitochondrial and death receptor pathways

Mono(2-ethylhexyl) phthalate (MEHP) is one of the main metabolites of di(2-ethylhexyl) phthalate. The evidence shows that DEHP may exert its toxic effects primarily via MEHP, which is 10-fold more potent than its parent compound in toxicity in vitro. MEHP-induced apoptosis is mediated by either p53-dependent or -independent pathway. However, the detailed mechanism of its toxicity remains unclear. In this study, immortalized normal human liver cell line L02 was chosen, as an in vitro model of nonmalignant liver, to elucidate the role of p53 in MEHP-induced apoptosis. The cells were treated with MEHP (6.25, 12.50, 25.00, 50.00, and 100.00 μM) for 24 and 36 h, then small interfering RNA (siRNA) was used to specifically silence p53 gene of L02 cells. The results indicated that MEHP caused oxidative DNA damage and apoptosis in L02 cells were associated with the p53 signaling pathway. Further study found that MEHP (50.00 and 100.00 μM) induced apoptosis in p53-silenced L02 cells, along with the up-regulations of Fas and FasL proteins as well as increased the Bax/Bcl-2 ratio and Caspase 3, 8, and 9 activities. Additionally, both FasL inhibitor (AF-016) and Caspase inhibitor N-benzyloxycarbonyl-Val-Ala-Asp- fluoromethylketone (Z-VAD-FMK) could prevent the cell apoptosis induced by MEHP. The findings suggested that MEHP-induced apoptosis in L02 cells involving a Caspases-mediated mitochondrial signaling pathway and/or death receptor pathway. p53 was not absolutely necessary for MEHP-induced L02 cell apoptosis.

Anti-tumor activities and apoptotic mechanism of ribosome-inactivating proteins

Ribosome-inactivating proteins (RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis. RIPs possess several biomedical properties, including anti-viral and anti-tumor activities. Multiple RIPs are known to inhibit tumor cell proliferation through inducing apoptosis in a variety of cancers, such as breast cancer, leukemia/lymphoma, and hepatoma. This review focuses on the anti-tumor activities of RIPs and their apoptotic effects through three closely related pathways: mitochondrial, death receptor, and endoplasmic reticulum pathways.

Chemical and biological insights into uranium-induced apoptosis of rat hepatic cell line

Uranium release into the environment is a threat to human health, and the mechanisms of cytotoxicity caused by uranium are not well-understood. To improve our understanding in this respect, we herein evaluated the effects of uranium exposure on normal rat hepatic BRL cells. As revealed by scanning electron microscopy and transmission electron microscope analysis, uranyl nitrate was found to be transformed into uranyl phosphate particles in the medium and taken up by BRL cells in an endocytotic uptake manner, which presumably initiates apoptosis of the cell, although soluble uranyl ion may also be toxic. The apoptosis of BRL cells upon uranium exposure was also confirmed by both the acridine orange and ethidium bromide double staining assay and the Annexin V/propidium iodide double staining assay. Further studies revealed that uranium induced the loss of mitochondrial membrane potential in a dose-dependent manner. Moreover, the uranium-induced apoptosis was found to be associated with the activation of caspase-3, caspase-8 and caspase-9, indicating both a mitochondria-dependent signaling pathway and a death receptor pathway by a crosstalk. This study provides new chemical and biological insights into the mechanism of uranium toxicity toward hepatic cells, which will help seek approaches for biological remediation of uranium.

Hsp70: anti-apoptotic and tumorigenic protein

Heat shock protein 70 (Hsp70) is a powerful chaperone whose expression is induced in response to a wide variety of physiological and environmental insults, including anticancer chemotherapy, thus allowing the cell to survive to lethal conditions. Hsp70 cytoprotective properties may be explained by its anti-apoptotic function. Indeed, this protein can inhibit key effectors of the apoptotic machinery at the pre- and postmitochondrial level. In cancer cells, the expression of Hsp70 is abnormally high, and Hsp70 may participate in oncogenesis and in resistance to chemotherapy. In rodent models, Hsp70 overexpression increases tumor growth and metastatic potential. Depletion or inhibition of Hsp70 frequently reduces the size of the tumors and even can cause their complete involution. But Hsp70 can also be found in the extracellular medium. Its role is then immunogenic and the term chaperokine to define the extracellular chaperones has been advanced. Hsp70 tumorigenic functions as well as the strategies that are being developed in cancer therapy in order to inhibit Hsp70 are commented in this chapter.

Phase I pharmacokinetic and biologic correlative study of mapatumumab, a fully human monoclonal antibody with agonist activity to tumor necrosis factor-related apoptosis-inducing ligand receptor-1

PURPOSE

To assess the safety, pharmacokinetics, and preliminary evidence of antitumor activity of mapatumumab (HGS-ETR1, TRM-1), a fully human agonist monoclonal antibody directed to the tumor necrosis factor-related apoptosis-inducing ligand receptor-1 (TRAIL-R1).

PATIENTS AND METHODS

Patients with advanced solid malignancies were treated with escalating doses of mapatumumab intravenously (IV) administered over 30 to 120 minutes, initially as a single dose and then repetitively. Plasma mapatumumab concentrations were measured and serum was assayed to detect human antimapatumumab antibody formation. Archival tumor specimens were collected to detect the presence of TRAIL-R1 by immunohistochemistry.

RESULTS

Forty-nine patients received 158 courses at doses ranging from 0.01 to 10 mg/kg IV. Initially, patients received mapatumumab as a single dose, then every 28 days repetitively, and then 10 mg/kg every 14 days. Mild (grade 1 or 2) fatigue, fever, and myalgia were the most frequently reported nonhematologic adverse events related to mapatumumab, whereas hematologic toxicity was not clinically significant. The mean (+/- standard deviation) clearance and terminal elimination half-life values for mapatumumab at 10 mg/kg every 14 days were 3.7 mL/d/kg (+/- 1.5 mL/d/kg) and 18.8 days (+/- 10.1 days), respectively. TRAIL-R1 was documented in 68% of patients' tumors assayed. Nineteen patients had stable disease, with two lasting 9 months.

CONCLUSION

Mapatumumab can be administered safely and feasibly at 10 mg/kg IV every 14 days. The absence of severe toxicities and the attainment of plasma mapatumumab concentrations that are active in preclinical models warrant further disease-directed studies of this agent alone and in combination with chemotherapy in a broad array of tumors.

Release of a membrane-bound death domain by gamma-secretase processing of the p75NTR homolog NRADD

Neurotrophin receptor alike death domain protein (NRADD) is a death-receptor-like protein with a unique ectodomain and an intracellular domain homologous to p75(NTR). Expression of NRADD results in apoptosis, but only in certain cell types. This paper characterizes the expression and proteolytic processing of the mature 55 kDa glycoprotein. N-terminally truncated NRADD is processed by a gamma-secretase activity that requires presenilins and has the same susceptibility to gamma-secretase inhibitors as the secretion of amyloid beta (A beta). The ectodomain of endogenous NRADD is shed by activation of metalloproteinases. Inhibitor studies provide evidence that NRADD is cleaved in two steps typical of regulated intramembrane proteolysis (RIP). Inhibition of gamma-secretase abrogates both the production of the soluble intracellular domain of NRADD and the appearance of NRADD in subnuclear structures. Thus, solubilized death domains with close homology to p75(NTR) might have a nuclear function. Furthermore, presenilin deficiency leads to abnormally glycosylated NRADD and overexpression of presenilin 2 inhibits NRADD maturation, which is dependent on the putative active site residue D366 but not on gamma-secretase activity. Our results demonstrate that NRADD is an additional gamma-secretase substrate and suggest that drugs against Alzheimer's disease will need to target gamma-secretase in a substrate-specific manner.

NRADD, a novel membrane protein with a death domain involved in mediating apoptosis in response to ER stress

NRADD (neurotrophin receptor alike death domain protein) is a novel protein with transmembrane and cytoplasmic regions highly homologous to death receptors, particularly p75(NTR). However, the short N-terminal domain is unique. Expression of NRADD induced apoptosis in a number of cell lines. The apoptotic mechanism involved the activation of caspase-8 and execution of apoptosis without requiring mitochondrial components. The activation of this death receptor-like mechanism required the N-terminal domain, which is N-glycosylated and needed for subcellular targeting. Deletion of the N-terminal domain produced a dominant-negative form of NRADD that protected neurons and Schwann cells from a variety of endoplasmic reticulum (ER) stressors. NRADD may therefore be a necessary component for generating an ER-induced proapoptotic signal.