A Novel Tetravalent CD95/Fas Fusion Protein With Superior CD95L/FasL Antagonism.

Inhibition of CD95/Fas activation is currently under clinical investigation as a therapy for glioblastoma multiforme and preclinical studies suggest that disruption of the CD95-CD95L interaction could also be a strategy to treat inflammatory and neurodegenerative disorders. Besides neutralizing anti-CD95L/FasL antibodies, mainly CD95ed-Fc, a dimeric Fc fusion protein of the extracellular domain of CD95 (CD95ed), is used to prevent CD95 activation. In view of the fact that full CD95 activation requires CD95L-induced CD95 trimerization and clustering of the resulting liganded CD95 trimers, we investigated whether fusion proteins of the extracellular domain of CD95 with a higher valency than CD95ed-Fc have an improved CD95L-neutralization capacity. We evaluated an IgG1(N297A)-based tetravalent CD95ed fusion protein which was obtained by replacing the variable domains of IgG1(N297A) with CD95ed (CD95ed-IgG1(N297A)) and a hexavalent variant obtained by fusion of CD95ed with a TNC-Fc(DANA) scaffold (CD95ed-TNC-Fc(DANA)) promoting hexamerization. The established N297A and DANA mutations were used to minimize FcγR binding of the constructs under maintenance of neonatal Fc receptor (FcRn) binding. Size exclusion high-performance liquid chromatography indicated effective assembly of CD95ed-IgG1(N297A). More important, CD95ed-IgG1(N297A) was much more efficient than CD95ed-Fc in protecting cells from cell death induction by human and murine CD95L. Surprisingly, despite its hexavalent structure, CD95ed-TNC-Fc(DANA) displayed an at best minor improvement of the capacity to neutralize CD95L suggesting that besides valency, other factors, such as spatial organization and agility of the CD95ed domains, play also a role in neutralization of CD95L trimers by CD95ed fusion proteins. More studies are now required to evaluate the superior CD95L-neutralizing capacity of CD95ed-IgG1(N297A) in vivo.

The development of anti-PD-1 antibody-induced spinal cord injury in bone marrow transplant C57BL/6 Rag1-/- mouse model.

Aims: This paper was to scrutinize the toxicity mechanism of anti-programmed death 1 (anti-PD-1) therapy-caused spinal cord injury (SCI). Methods: Bone marrow transplant Rag1-/- mice were used to establish SCI model. Results: Anti-PD-1 results in SCI via CD8+ T-cells activation, while excessive activation of CD8+ T-cells further aggravated SCI. Both anti-PD-1 and the activation of CD8+ T-cells induced the expression of apoptosis-related perforin, GrB and FasL, but suppressed PI-9 level. The opposite results were observed in the effects of neuroserpin on these factors. CD8+ T-cells activation induced neurotoxicity via upregulation perforin, GrB and FasL and inhibiting PI-9. Additionally, neuroserpin suppressed CD8+ T-cells activation via perforin/GrB/PI-9/FasL pathways. Conclusion: These results may provide theoretical foundation for the clinical treatment of SCI caused by anti-PD-1.

What is this article about? In the process of treating cancer, immune checkpoint inhibitors such as anti-programmed death 1 (anti-PD-1) therapy, as a form of immunotherapy, have developed rapidly and changed the way to manage cancers significantly. However, some cancer patients who receive immune checkpoint blockade treatment suffer from severe adverse effects including spinal cord injury (SCI). This article for the first time constructed a bone marrow transplant mouse model to explore the toxicity mechanism of anti-PD-1 therapy-caused SCI.What were the results? We found that anti-PD-1 therapy can induce the activation of immune cells, while immune cell activation further promotes self-destruction of nerve cells by regulating cell death pathways.What do the results of the study mean? The mechanism of anti-PD-1 therapy-caused SCI is to activate of immune cells through regulating cell death pathways, thereby inducing self-destruction of nerve cells. These findings provide theoretical foundation for the clinical treatment of SCI caused by anti-PD-1 therapy.

Apoptotic Receptors and CD107a Expression by NK Cells in an Interaction Model with Trophoblast Cells.

Natural killer cells (NK cells) exert cytotoxicity towards target cells in several ways, including the expression of apoptosis-mediating ligands (TRAIL, FasL). In addition, NK cells themselves may be susceptible to apoptosis due to the expression of TRAIL receptors. These receptors include TRAIL-R1 (DR4), TRAIL-R2 (DR5), capable of inducing apoptosis, and TRAIL-R3 (DcR1), TRAIL-R4 (DcR2), the so-called "decoy receptors", which lack an intracellular domain initiating activation of caspases. Of particular interest is the interaction of uterine NK cells with cells of fetal origin, trophoblasts, which are potential targets for natural killer cells to carry out cytotoxicity. The aim of this work was to evaluate the expression of proapoptotic receptors and their ligands as well as CD107a expression by NK cells in a model of interaction with trophoblast cells. To evaluate NK cells, we used cells of the NK-92 line; cells of the JEG-3 line were used as target cells. The cytokines IL-1ß, IL-15, IL-18, TNFα, IL-10, TGFß and conditioned media (CM) of the first and third trimester chorionic villi explants were used as inducers. We established that cytokines changed the expression of apoptotic receptors by NK cells: in the presence of TNFα, the amount and intensity of Fas expression increased, while in the presence of TGFß, the amount and intensity of expression of the DR5 receptor decreased. Soluble chorionic villi factors alter the expression of TRAIL and FasL by NK-92 cells, which can reflect the suppression of the TRAIL-dependent mechanism of apoptosis in the first trimester and stimulating the Fas-dependent mechanism in the third trimester. In the presence of trophoblast cells, the expression of TRAIL and DcR1 by NK cells was reduced compared to intact cells, indicating an inhibitory effect of trophoblast cells on NK cell cytotoxicity. In the presence of chorionic villi CM and trophoblast cells, a reduced number of NK-92 cells expressing DR4 and DR5 was found. Therefore, soluble factors secreted by chorionic villi cells regulate the resistance of NK cells to death by binding TRAIL, likely maintaining their activity at a certain level in case of contact with trophoblast cells.

NFAT3-FasL axis synchronously regulates apoptosis and necroptosis in murine cochlear outer hair cells after noise trauma.

Existing studies have indicated that noise induces apoptosis and necroptosis in cochlear outer hair cells (OHCs). However, the role of the extrinsic cell death pathway, initiated by death ligands in the cochlea, remains unknown. In this study, we hypothesized that noise could induce the NFAT3/FasL axis-mediated extrinsic death pathway in the cochlea. We found that NFAT3/FasL signaling was silent in normal OHCs. Noise exposure induced apoptosis and necroptosis in OHCs with specifically high FasL expression. Multiplex immunofluorescence staining revealed that NFAT3 nuclear translocation and FasL upregulation were colocalized in the apoptotic and necroptotic OHCs following noise trauma. Administration of FK506 or 11R-vivit (an specific NFAT inhibitor) blocked NFAT3 nuclear translocation, inhibited FasL expression, mitigated apoptosis and necroptosis, and protected against noise-induced hearing loss (NIHL). Finally, FasL knockdown by delivering siRNA intratympanically attenuated apoptosis and necroptosis in OHCs and alleviated NIHL, confirming the role of FasL in OHC death. Collectively, our study demonstrates that the NFAT3/FasL axis mediates noise-induced extrinsic death pathway in OHCs, leading to their apoptosis and necroptosis.

FSH induces apoptosis in follicular granulosa cells of Tianzhu white yak and regulates the expression of Fas/FasL mRNA.

The Tianzhu white yak, a globally rare species, holds immense value as a source for yak materials. While the Fas/FasL pathway is pivotal in granulosa cells apoptosis, its precise molecular workings remain enigmatic. This study endeavours to decipher the role of follicle-stimulating hormone (FSH) in suppressing ovarian granulosa cells (GC) apoptosis in the Tianzhu white yak. Utilizing advanced cell culture techniques, we employed the MTT method, flow cytometry, fluorescence labelling and RT-PCR to investigate the apoptotic effects of FSH on yak GCs. Our results reveal that FSH's inhibitory effect on GC apoptosis follows a normal distribution pattern, peaking at an FSH concentration of 100 ng/mL with an apoptosis inhibition rate of 89.31%. When serum was withdrawn, an FSH concentration of 2 × 106 ng/mL reduced apoptosis by 72.84%. Annexin V-FITC staining revealed membrane invaginations, bubble and protrusion formation on the cell surface, and alterations in membrane structure and cell morphology. Flow cytometry analysis further demonstrated that FSH administration prior to early granulosa cell apoptosis had a more profound effect than during gradual apoptosis, both showing a suppressive effect on early follicular granulosa cell apoptosis. A transcription-level analysis conducted 3 h prior to serum withdrawal, with the addition of 100 ng/mL FSH, revealed intricate regulations in the expression of Fas/FasL. Notably, we observed a gradual increase in FasL expression over time, yet the presence of FSH effectively down-regulated FasL expression to baseline levels, without notable changes in Fas expression. Immunocytochemical analysis further confirmed the presence of both Fas and FasL on the cell membrane, nucleus and cytoplasm, with varying intensities depending on the duration of FSH treatment. Our findings suggest that FSH may suppress the apoptotic pathway in follicular primarily by down-regulating FasL expression, indicating that Fas-regulated mitochondrial pathways play a more prominent role compared to death receptor pathways. This study offers a fresh perspective on the mechanism underlying follicular atresia in Tianzhu white yaks and lays a solid theoretical foundation for the expansion of this endangered species' population.

Low-dose doxorubicin loaded extracellular vesicles combined Fas/FasL pathway-mediated chemo-sensitization and immunotherapy against tumor.

The clinical application of doxorubicin (DOX) is mainly restricted by its serious side effects, poor drug delivery efficiency, and limited immunogenic death (ICD) effect. To improve DOX-based chemotherapy and ameliorate its adverse effects, we utilized 3LL cell-derived extracellular vesicles to encapsulate DOX and sodium nitroprusside (SNP) to obtain DOX/SNP@CM, which could effectively target the tumor site by harnessing the inherent homologous targeting property of tumor cell membranes. DOX performed its role on chemotherapy, and SNP successfully respond to the intracellular GSH to continuously generate nitric oxide (NO). The in situ-produced NO upregulated the Fas expression on the tumor cell surface, thereby sensitizing the Fas/FasL pathway-mediated tumor cell apoptosis of DOX. Furthermore, NO also boosted the intratumoral infiltration of cytotoxic T cells by promoted ICD effect towards tumor cells. Importantly, the anti-tumor immunity tightly cooperated with Fas/FasL mediated tumor cell apoptosis by NO-mediated manipulation on Fas/FasL interaction, collectively making DOX/SNP@CM exert significant tumor growth inhibition with low-dose DOX. Remarkably, DOX and SNP both are widely used clinical medicines, ensuring DOX/SNP@CM a potential opportunity for future practical applications.

Matrix metalloproteinase/Fas ligand (MMP/FasL) interaction dynamics in COVID-19: An in silico study and neuroimmune perspective.

Background: The initiator of cytokine storm in Coronavirus disease (COVID-19) is still unknown. We recently suggested a complex interaction of matrix metalloproteinases (MMPs), Fas ligand (FasL), and viral entry factors could be responsible for the cytokine outrage In COVID-19. We explored the molecular dynamics of FasL/MMP7-9 in COVID-19 conditions in silico and provide neuroimmune insights for future. Methods: We enrolled and analyzed a clinical cohort of COVID-19 patients, and recorded their blood Na + levels and temperature at admission. A blood-like molecular dynamics simulation (MDS) box was then built. Four conditions were studied; MMP7/FasL (healthy), MMP7/FasL (COVID-19), MMP9-FasL (healthy), and MMP9/FasL (COVID-19). MDS was performed by GROningen MAchine for Chemical Simulation (GROMACS). We analyzed bonds, short-range energies, and free binding energies to draw conclusions on the interaction of MMP7/MMP9 and FasL to gain insights into COVID-19 immunopathology. Genevestigator was used study RNA-seq/microarray expression data of MMPs in the cells of immune and nervous systems. Finally, epitopes of MMP/FasL complexes were identified as drug targets by machine learning (ML) tools. Results: MMP7-FasL (Healthy), MMP7-FasL (COVID-19), MMP9-FasL (Healthy), and MMP9-FasL (COVID-19) systems showed 0, 1, 4, and 2 salt bridges, indicating MMP9 had more salt bridges. Moreover, in both COVID-19 and normal conditions, the number of interacting residues and surface area was higher for MMP9 compared to MMP7 group. The COVID-19 MMP9-FasL group had more H-bonds compared to MMP7-FasL group (12 vs. 7). 15 epitopes for FasL-MMP9 and 10 epitopes for FasL-MMP7 were detected. Extended MD simulation for 100 ns confirmed stronger binding of MMP9 based on Molecular Mechanics Generalized Borne Surface analysis (MM-GBSA) and Coul and Leonard-Jones (LJ) short-range energies. Conclusions: MMP9 interacts stronger than MMP7 with FasL, however, both molecules maintained strong interaction through the MDS. We suggested epitopes for MMP-FasL complexes as valuable therapeutic targets in COVID-19. These data could be utilized in future immune drug and protein design and repurposing efforts.

Effect of Granzyme K, FasL and Interferon-γ Expression in Placentas with Preeclampsia.

This study aimed to investigate the cytotoxic activity of decidual lymphocytes and the mRNA/protein expression of cytotoxic proteins in various cell types in the context of preeclampsia (PE) compared to those of healthy pregnancies. We analyzed fresh decidua basalis tissue and tissue embedded in paraffin (FFPE) from PE pregnancies (n = 15) and compared them with those of healthy pregnancies (n = 15) of the corresponding gestational age. Using double immunofluorescence staining, we observed differences in the intensity and distribution of staining for granzyme K (GZMK) and FasL in extravillous trophoblasts. RT-qPCR analysis of FFPE placental tissue showed that GZMK mRNA expression was statistically higher (p < 0.0001) in PE compared to that of healthy controls. On the contrary, there was a low expression (p < 0.001) of FasL mRNA in PE compared to controls, while there was no statistically significant difference for IFN-γ mRNA between PE and controls. Although the level of cytotoxic activity changed depending on the ratio of effector and target cells, there was no significant difference observed between PE and controls in this in vitro study. In conclusion, in PE, extravillous trophoblasts exhibited increased expression of GZMK and decreased expression of FasL. These changes may contribute to impaired trophoblast invasion. However, these alterations did not appear to affect the cytotoxic properties of decidual lymphocytes. Additionally, the possibility of cell sorter separation of decidual lymphocytes would greatly contribute to a better understanding of single cells' genetic profiles.

Fas ligand regulate nerve injury and repair by affecting AKT, ß-catenin, and NF-κB pathways.

Objective: To investigate the regulatory effect of Fas-L on the repair and regeneration of peripheral extension injury in rats. Methods: This study aimed to explore the effects of Fas-L on apoptosis and axonal regeneration of dorsal root ganglion (DRG) cells in rat peripheral nerve repair and regeneration by using several relevant experimental techniques from the injured nerve animal model, cell biology, and molecular biology. Results: The expression level of Fas-L in DRG tissues was significantly down-regulated after sciatic nerve injury. Interference with Fas-L can significantly promote the regeneration of DRG neuronal axons and inhibit apoptosis, while the overexpression of Fas-L is contrary to it. Moreover, Fas-L may play a role in the regulation of DRG function and the repair and regeneration of peripheral nerves in Sprague Dawley (SD) rats by affecting several signaling pathways, such as p-AKT/AKT, ß-catenin, and NF-κB. Conclusion: Fas-L may have a certain effect on the repair and regeneration of peripheral nerve injury in SD rats, which may provide an experimental basis and a new theoretical basis for the functional reconstruction of peripheral nerves. Significance statement: The expression level of Fas-L in DRG tissues was significantly down-regulated after sciatic nerve injury. Fas-L can significantly promote the regeneration of DRG neuronal axons and inhibit apoptosis. Fas-L may play a role in the regulation of DRG function and the repair and regeneration of peripheral nerves in SD rats by affecting several signaling pathways, such as p-AKT/AKT, ß-catenin, and NF-κB. Fas-L may have a certain effect on the repair and regeneration of peripheral nerve injury in SD rats, which may provide an experimental basis and a new theoretical basis for the functional reconstruction of peripheral nerves.

A novel triad for the diagnosis of endometriosis, the short anogenital distance combines with high endometrial BCL2 and low endometrial FASL.

OBJECTIVE: To investigate the anogenital distance from the upper verge of the anus to the posterior fourchette (AGDAF), FASL, and BCL2 combination as a reliable and non-invasive tool for the diagnosis of endometriosis. METHODS: This study included 100 women with endometriosis and 50 women without endometriosis as the control group. All cases underwent history taking, body mass index (BMI) measurement, AGD measurement, and FASL and BCL2 immunohistochemical staining of the eutopic endometrial tissue. RESULTS: This study included 150 women divided into endometriosis and control groups. Endometriosis cases significantly had shorter AGDAF, 22.9 ± 2.6 mm, compared with the control group, 27.3 ± 3.5 mm (P < 0.001). Lower FASL and higher BCL2 expression were associated with endometriosis (P < 0.001). The combined measurement of AGDAF (cut-off point 24.55 mm) with FASL and BCL2 was associated with endometriosis (P < 0.001). The combined diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of AGDAF, FASL, and BCL2 were 83%, 78%, 87.3%, and 69.6%, respectively. The area under the curve was greater for AGDAF, FASL, and BCL2 in combination than for individual measurements. CONCLUSION: Combining short AGDAF with high BCL2 and low FASL is a highly sensitive, non-invasive diagnostic tool for endometriosis.

Corrigendum: Blocking soluble Fas Ligand ameliorates pemphigus: PC111 efficacy in ex-vivo human pemphigus models.

[This corrects the article DOI: 10.3389/fimmu.2023.1193032.].

Tissue-targeted and localized AAV5-DCN and AAV5-PEDF combination gene therapy abrogates corneal fibrosis and concurrent neovascularization in rabbit eyes in vivo.

PURPOSE: Corneal fibrosis and neovascularization (CNV) after ocular trauma impairs vision. This study tested therapeutic potential of tissue-targeted adeno-associated virus5 (AAV5) mediated decorin (DCN) and pigment epithelium-derived factor (PEDF) combination genes in vivo. METHODS: Corneal fibrosis and CNV were induced in New Zealand White rabbits via chemical trauma. Gene therapy in stroma was delivered 30-min after chemical-trauma via topical AAV5-DCN and AAV5-PEDF application using a cloning cylinder. Clinical eye examinations and multimodal imaging in live rabbits were performed periodically and corneal tissues were collected 9-day and 15-day post euthanasia. Histological, cellular, and molecular and apoptosis assays were used for efficacy, tolerability, and mechanistic studies. RESULTS: The AAV5-DCN and AAV5-PEDF combination gene therapy significantly reduced corneal fibrosis (p < 0.01 or p < 0.001) and CNV (p < 0.001) in therapy-given (chemical-trauma and AAV5-DCN + AAV5-PEDF) rabbit eyes compared to the no-therapy given eyes (chemical-trauma and AAV5-naked vector). Histopathological analyses demonstrated significantly reduced fibrotic α-smooth muscle actin and endothelial lectin expression in therapy-given corneas compared to no-therapy corneas on day-9 (p < 0.001) and day-15 (p < 0.001). Further, therapy-given corneas showed significantly increased Fas-ligand mRNA levels (p < 0.001) and apoptotic cell death in neovessels (p < 0.001) compared to no-therapy corneas. AAV5 delivered 2.69 × 107 copies of DCN and 2.31 × 107 copies of PEDF genes per µg of DNA. AAV5 vector and delivered DCN and PEDF genes found tolerable to the rabbit eyes and caused no significant toxicity to the cornea. CONCLUSION: The combination AAV5-DCN and AAV5-PEDF topical gene therapy effectively reduces corneal fibrosis and CNV with high tolerability in vivo in rabbits. Additional studies are warranted.

The expression of corticotropin-releasing hormone family peptides in premalignant and malignant vulvar lesions.

OBJECTIVES: To examine the relation of corticotropin-releasing hormone (CRH) family peptides with inflammatory processes and oncogenesis, emphasizing in vulvar inflammatory, premalignant and malignant lesions, as well as to investigate the possibility of lesion cells immunoescaping, utilizing FAS/FAS-L complex. METHODS: Immunohistochemical expression of CRH, urocortin (UCN), FasL and their receptors CRHR1, CRHR2 and Fas was studied in vulvar tissue sections obtained from patients with histologically confirmed diagnosis of lichen, vulvar intraepithelial neoplasia (VIN) and vulvar squamous cell carcinoma (VSCC). The patient cohort was selected from a tertiary teaching Hospital in Greece, between 2005 and 2015. For each of the disease categories, immunohistochemical staining was evaluated and the results were statistically compared. RESULTS: A progressive increase of the cytoplasmic immunohistochemical expression of CRH and UCN, from precancerous lesions to VSCC was observed. A similar increase was detected for Fas and FasL expression. Nuclear localization of UCN was demonstrated in both premalignant and VSCC lesions, with staining being significantly intensified in carcinomas, particularly in the less differentiated tumor areas or in the areas at invasive tumor front. CONCLUSIONS: Stress response system and CRH family peptides seem to have a role in inflammation maintenance and progression of vulvar premalignant lesions to malignancy. It seems that stress peptides may locally modulate the stroma through Fas/FasL upregulation, possibly contributing to vulvar cancer development.

Fas ligand intracellular signaling: does PSTPIP mediate T cell death?

Fas and Fas ligand (FasL)-induced cell death is critical for the appropriate regulation of immune responses, especially those mediated by T cells. In this letter, several studies are discussed that reinforce the importance of FasL intracellular signaling for CD4 + T cell death, which might involve PSTPIP phosphatase and/or MAPKs.

Activation and Denitrosylation of Procaspase-3 in KA-induced Excitotoxicity.

BACKGROUND: It has been reported that activation of glutamate kainate receptor subunit 2 (GluK2) subunit-containing glutamate receptors and the following Fas ligand(FasL) up-regulation, caspase-3 activation, result in delayed apoptosis-like neuronal death in hippocampus CA1 subfield after cerebral ischemia and reperfusion. Nitric oxide-mediated S-nitrosylation might inhibit the procaspase activation, whereas denitrosylation might contribute to cleavage and activation of procaspases. OBJECTIVES: The study aimed to elucidate the molecular mechanisms underlying procaspase-3 denitrosylation and activation following kainic acid (KA)-induced excitotoxicity in rat hippocampus. METHODS: S-nitrosylation of procaspase-3 was detected by biotin-switch method. Activation of procaspase-3 was shown as cleavage of procaspase-3 detected by immunoblotting. FasL expression was detected by immunoblotting. Cresyl violets and TdT-mediated dUTP Nick-End Labeling (TUNEL) staining were used to detect apoptosis-like neuronal death in rat hippocampal CA1 and CA3 subfields. RESULTS: KA led to the activation of procaspase-3 in a dose- and time-dependent manner, and the activation was inhibited by KA receptor antagonist NS102. Procaspase-3 was denitrosylated at 3 h after kainic acid administration, and the denitrosylation was reversed by SNP and GSNO. FasL ASODNs inhibited the procaspase-3 denitrosylation and activation. Moreover, thioredoxin reductase (TrxR) inhibitor auranofin prevented the denitrosylation and activation of procaspase-3 in rat hippocampal CA1 and CA3 subfields. NS102, FasL AS-ODNs, and auranofin reversed the KAinduced apoptosis and cell death in hippocampal CA1 and CA3 subfields. CONCLUSIONS: KA led to denitrosylation and activation of procaspase-3 via FasL and TrxR. Inhibition of procaspase-3 denitrosylation by auranofin, SNP, and GSNO played protective effects against KA-induced apoptosis-like neuronal death in rat hippocampal CA1 and CA3 subfields. These investigations revealed that the procaspase-3 undergoes an initial denitrosylation process before becoming activated, providing valuable insights into the underlying mechanisms and possible treatment of excitotoxicity.

TP induces hepatic intolerance to FasL-mediated hepatocyte apoptosis by inhibiting XIAP.

Triptolide (TP) is extracted from the traditional Chinese medicine Tripterygium wilfordii Hook. F. (TWHF). Its severe toxic side effects, especially hepatotoxicity, have limited the clinical application of TP-related drugs. In this study, we investigated the mechanism of the hepatotoxic effects of TP from the perspective that TP inhibited the expression of the pro-survival protein X-linked inhibitor of apoptosis protein (XIAP) and enhanced FasL-mediated apoptosis of hepatocytes. TP and CD95/Fas antibody (Jo-2) were administered by gavage to C57BL/6 mice for 7 consecutive days. After co-administration of TP and Jo-2, mouse livers showed large areas of necrosis and apoptosis and significantly increased Caspase-3 activity. KEGG pathway enrichment analysis indicated that TP may cause the development of liver injury through the apoptotic signaling pathway. Proteinprotein interaction networks showed that XIAP played an essential role in this process. TP reduced the protein expression of XIAP after combination treatment with Jo-2/FasL in vivo/in vitro. TP and FasL co-stimulation significantly increased microRNA-137 (miR-137) levels in AML12 cells, while inhibition of miR-137 expression induced a rebound in XIAP protein expression. In conclusion, TP presensitizes hepatocytes and enhances the sensitivity of hepatocytes to the Fas/FasL pathway by inhibiting the protein expression of XIAP, leading to hepatocyte apoptosis.

Sulforaphene suppressed cell proliferation and promoted apoptosis of COV362 cells in endometrioid ovarian cancer.

Aim: N6-methyladenosine (m6A) RNA methylation exerts a regulatory effect on endometrioid ovarian cancer (EOC), but the specific m6A regulator genes in EOC remain to be explored. This study investigated that sulforaphene (Sul) is implicated in EOC development by regulating methyltransferase-like 3 (METTL3). Methods: The dysregulated m6A RNA methylation genes in EOC were determined by methylated RNA immunoprecipitation (MeRIP-seq) and RNA sequencing. The roles of METTL3 and/or Sul on viability, proliferative ability, cell cycle, and apoptosis of EOC cells were determined by MTT, colony formation, flow cytometry, and TUNEL staining assay, respectively. The expression of METTL3 and apoptosis-related proteins in EOC cells was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot assays. Results: Five m6A RNA methylation regulators (METTL3, ELF3, IGF2BP2, FTO, and METTL14) were differentially expressed in EOC, among which METTL3 had the highest expression level. Silencing METTL3 reduced the clonal expansion and viability of EOC cells, and caused the cells to arrest in the G0/G1 phase. This also promoted apoptosis in the EOC cells and activated the FAS/FADD and mitochondrial apoptosis pathways. In contrast, overexpressing METTL3 had the opposite effect. Sul, in a dose-dependent manner, reduced the viability of EOC cells but promoted their apoptosis. Sul also increased the levels of IGF2BP2 and FAS, while decreasing the levels of KRT8 and METTL3. Furthermore, Sul was able to reverse the effects of METTL3 overexpression on EOC cells. Conclusions: Sul could suppress cell proliferation and promote apoptosis of EOC cells by inhibiting the METTL3 to activate the FAS/FADD and apoptosis-associated pathways.

Let-7a promotes periodontal bone regeneration of bone marrow mesenchymal stem cell aggregates via the Fas/FasL-autophagy pathway.

Periodontal bone regeneration using bone marrow mesenchymal stem cell (BMMSC) transplantation is a promising method; however, the method for osteogenic differentiation of BMMSCs needs to be improved. In this research, we sought to identify the roles of let-7a in the osteogenesis of BMMSCs and to provide a potential method for periodontal bone regeneration. Our previous study revealed that Fas/FasL is a target of let-7a. In this study, we demonstrated that let-7a overexpression significantly enhanced BMMSC-CAs osteogenesis both in vitro and in vivo. Mechanistically, upregulation of Fas/FasL using the rfas/rfaslg plasmid obstructed the osteogenesis of BMMSCs by inhibiting autophagy. Furthermore, we confirmed that overexpression of let-7a activated autophagy and alleviated the inhibited osteogenesis by the autophagy inhibitor 3-MA and the rfas/rfaslg plasmid of BMMSCs. In general, our findings showed that let-7a promoted the osteogenesis of BMMSCs through the Fas/FasL-autophagy pathway, suggesting that the application of let-7a in BMMSC-CAs based periodontal bone regeneration could be a promising strategy.