Anthraquinone modifier KA-4c triggers endoplasmic reticulum stress and targets ATF6 against breast cancer cells / 中国药理学通报

Aim To explore the mechanism of the effect of anthraquinone modifier KA-4c on breast cancer cells, and determine its action target by drug affinity reaction target stability technique (DARTS). Methods The cell viability was detected by MTT method. The effect of KA-4c on the morphology of breast cancer cells was studied by HE staining, ER-Tracker Red and electron microscope. The apoptosis rate of breast cancer cells induced by KA-4c was detected by flow cytometry. The expression of apoptotic protein was detected by Western blotting. DARTS and CETSA were used to determine the target of KA-4c. Results KA-4c had the most significant inhibitory effect on the proliferation of triple negative breast cancer MDA-MB231 cells, and could cause endoplasmic reticulum and mitochondrial vacuolation to damage the cells. The apoptosis rate and the expression of apoptosis-related proteins CHOP and caspase-7 increased with the increase of KA-4c concentration. DARTS results showed that KA-4c could activate endoplasmic reticulum protein processing signaling pathway, in which KA-4c bound to ATF6 protein and was resistant to protease hydrolysis. The results of CETSA experiments showed that KA-4c could enhance the expression of ATF6 protein in a concentration-dependent manner. Conclusions KA-4 triggers endoplasmic reticulum stress to induce apoptosis in breast cancer cells. ATF6 may be one of the targets of KA-4c.

A cyclodextrin-based nanoformulation achieves co-delivery of ginsenoside Rg3 and quercetin for chemo-immunotherapy in colorectal cancer

The immune checkpoint blockade therapy has profoundly revolutionized the field of cancer immunotherapy. However, despite great promise for a variety of cancers, the efficacy of immune checkpoint inhibitors is still low in colorectal cancer (CRC). This is mainly due to the immunosuppressive feature of the tumor microenvironment (TME). Emerging evidence reveals that certain chemotherapeutic drugs induce immunogenic cell death (ICD), demonstrating great potential for remodeling the immunosuppressive TME. In this study, the potential of ginsenoside Rg3 (Rg3) as an ICD inducer against CRC cells was confirmed using in vitro and in vivo experimental approaches. The ICD efficacy of Rg3 could be significantly enhanced by quercetin (QTN) that elicited reactive oxygen species (ROS). To ameliorate in vivo delivery barriers associated with chemotherapeutic drugs, a folate (FA)-targeted polyethylene glycol (PEG)-modified amphiphilic cyclodextrin nanoparticle (NP) was developed for co-encapsulation of Rg3 and QTN. The resultant nanoformulation (CD-PEG-FA.Rg3.QTN) significantly prolonged blood circulation and enhanced tumor targeting in an orthotopic CRC mouse model, resulting in the conversion of immunosuppressive TME. Furthermore, the CD-PEG-FA.Rg3.QTN achieved significantly longer survival of animals in combination with Anti-PD-L1. The study provides a promising strategy for the treatment of CRC.

Clinical and genetic features of a Chinese family with ATF6-associated achromatopsia / 中华实验眼科杂志

Objective:To identify the clinical characteristics and pathogenic gene of a Chinese Han family with achromatopsia (ACHM).Methods:The method of pedigree investigation was adopted.A Chinese Han ACHM family was recruited in Peking Union Medical College Hospital form July 2010 to July 2019, including 5 members of 2 generations.There were 2 patients and 3 phenotypically normal individuals.The medical history was collected and comprehensive ophthalmic examinations were performed, including visual acuity, colour vision, color fundus photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), visual field and electroretinogram (ERG).Genomic DNA was extracted from peripheral blood sample from the patients and family members.Pathogenic variant was screened by whole exome sequencing (WES) and verified by Sanger sequencing and co-segregation analysis.The variant was annotated with the 1000 Genomes, Human Gene Mutation Database (HGMD), ExAC, ClinVar and OMIM databases to detect the single nucleotide polymorphism and whether it had been reported previously.The pathogenicity of the variant was evaluated according to the standards and guidelines of the American College of Medical Genetics and Genomics (ACMG).This study adhered to the Declaration of Helsinki.The study protocol was approved by the Institutional Review Board of Peking Union Medical College Hospital (No.JS-2059).Written informed consent was obtained from the guardians of juvenile patients.Results:There was consanguinity between the proband's parents and this family was consistent with autosomal recessive inheritance.Both male patients presented the reduction of visual acuity accompanied with photophobia and color blindness since childhood.Barely visible foveal light reflex in fundus images, hypofluorescence of foveal areas in FAF images, foveal defect with disruption of ellipsoid zone and interdigitation zone in OCT images were found in both patients.Central scotoma with or without peripheral visual field defects was detected.Generally normal scotopic 0.01, 3.0 and 10.0 responses, decreased oscillatory potentials amplitudes, no photopic 3.0 and 30 Hz flicker responses were observed.No sign of progression was found during the 9-year follow-up.It was confirmed that both patients carried a novel homozygous disease-causing variant c. 947insA (p.Asn316Lysfs*46) in ATF6 gene.Their mother had the heterozygous variant.The unaffected brother did not carry the variant.This family was consistent with co-segregation.This variant was labeled as pathogenic according to the ACMG standards and guidelines. Conclusions:A novel variant c.947insA (p.Asn316Lysfs*46) in ATF6 gene is the pathogenic variant of this achromatopsia family.This is the first time that this variant has been reported.

FoxO1 regulates Hcyinduced hepatocyte apoptosis through ATF6 / 中国药理学通报

: Aim To explore the role and possible mechanism of forked transcription factor (FoxO1) in hepatocyte apoptosis induced by homocysteine (Hey) . Methods The male cbs

SMYD3-PARP16 axis accelerates unfolded protein response and mediates neointima formation

Neointimal hyperplasia after vascular injury is a representative complication of restenosis. Endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) is involved in the pathogenesis of vascular intimal hyperplasia. PARP16, a member of the poly(ADP-ribose) polymerases family, is correlated with the nuclear envelope and the ER. Here, we found that PERK and IRE1

Natural compounds modulate the autophagy with potential implication of stroke

Stroke is considered a leading cause of mortality and neurological disability, which puts a huge burden on individuals and the community. To date, effective therapy for stroke has been limited by its complex pathological mechanisms. Autophagy refers to an intracellular degrading process with the involvement of lysosomes. Autophagy plays a critical role in maintaining the homeostasis and survival of cells by eliminating damaged or non-essential cellular constituents. Increasing evidence support that autophagy protects neuronal cells from ischemic injury. However, under certain circumstances, autophagy activation induces cell death and aggravates ischemic brain injury. Diverse naturally derived compounds have been found to modulate autophagy and exert neuroprotection against stroke. In the present work, we have reviewed recent advances in naturally derived compounds that regulate autophagy and discussed their potential application in stroke treatment.

A small molecule UPR modulator for diabetes identified by high throughput screening

Unfolded protein response (UPR) is a stress response that is specific to the endoplasmic reticulum (ER). UPR is activated upon accumulation of unfolded (or misfolded) proteins in the ER's lumen to restore protein folding capacity by increasing the synthesis of chaperones. In addition, UPR also enhances degradation of unfolded proteins and reduces global protein synthesis to alleviate additional accumulation of unfolded proteins in the ER. Herein, we describe a cell-based ultra-high throughput screening (uHTS) campaign that identifies a small molecule that can modulate UPR and ER stress in cellular and

A preliminary study on thapsigargin promoting coxsackievirus B3 replication through activating transcription factor 6 pathway / 中华实验和临床病毒学杂志

Objective@#To investigate the effect of thapsigargin (TG) which can induce endoplasmic reticulum stress (ERS) on the replication of coxsackievirus B 3 (CV-B3).@*Methods@#After 10 MOI CV-B3 infected HeLa cells were exposed 0.25 μmol/L TG for 3 h, 6 h and 9 h, virus RNA of HeLa cells were extracted and viral replication was evaluated by real time PCR. After 0.25 μmol/L、0.08 μmol/L and 0.025 μmol/L TG exposed, the plaque of CV-B3 was used to confirm further replication of CV-B3. To verify TG induced ERS through three signal pathway, one of among PERK, ATF6 and IRE1 inhibitors GSK2656157, AEBSF and STF-083010, and 0.25 μmol/L TG were used in HeLa cells infected with 10 MOI CV-B3, replication of CV-B3 was evaluated by qRT-PCR.@*Results@#The stimulation of TG did not induce increase of virus replication after post-infection 3 h. However, TG induced replication of virus to increase 2.5 times after post-infection 6 h and 158.6 times after post-infection 9 h. And, the area of viral plaque was significantly increased. ATF6 inhibitors AEBSF significantly inhibited promotion of virus replication from TG.@*Conclusions@#TG can promote the replication of CV-B3 through ATF6 signal pathway.

Protective effect of notoginsenoside R1 on neuron injury induced by OGD/R through ATF6/Akt signaling pathway / 中国中药杂志

Notoginsenoside R1(NGR1),a critical compound in traditional herb Panax notoginseng, is a kind of estrogen receptor agonist.It is reported to exhibit anti-apoptotic,anti-oxidative and anti-inflammatory properties activity, so it is widely used for treatment of various diseases.In order to investigate the potential neuroprotective effect of NGR1 in hypoxic-ischemic brain damage(HIBD), primary cortical neurons were used in this study to establish oxygen-glucose deprivation/reoxygenation(OGD/R) injury models. They were treated with NGR1 and estrogen receptor inhibitor ICI-182780 respectively, then the neuronal survival, cell membrane integrity and apoptosis were assessed by MTT assay,lactate dehydrogenase test(LDH) and Hoechst 33342 stain respectively, while the protein expression levels of ATF6α,p-Akt,Akt,Bax and Cleaved Caspase-3 were measured by Western blotting. Results indicated that as compared with the blank control group,OGD/R could induce cell injury and apoptosis(P<0.05), reduce relative integrity of cell membrane(P<0.05), decrease protein expression of ATF6α,p-Akt(P<0.05), and increase protein expression of Bax and Cleaved Caspase-3(P<0.05) in the primary cortical cells. After NGR1 treatment, the expression levels of ATF6α,p-Akt were obviously increased, and the expression levels of Bax and Cleaved Caspase-3 and the apoptosis of neuron were decreased(P<0.05). However, these neuroprotective properties of NGR1 against ODG/R-induced cell damage could be blocked by ICI-182780. This finding indicated that NGR1 may protect the primary cortical neurons against OGD/R induced injury,and the mechanism may be associated with accelerating the activation of the ATF6/Akt signaling pathway via estrogen receptors.

Polymorphisms of ATF6B Are Potentially Associated With FEV1 Decline by Aspirin Provocation in Asthmatics

PURPOSE: Endoplasmic reticulum (ER) stress has recently been observed to activate NF-kappaB and induce inflammatory responses such as asthma. Activating transcription factor 6beta (ATF6B) is known to regulate ATFalpha-mediated ER stress response. The aim of this study is to investigate the associations of ATF6B genetic variants with aspirin-exacerbated respiratory disease (AERD) and its major phenotype, % decline of FEV1 by aspirin provocation. METHODS: Four common single nucleotide polymorphisms (SNPs) of ATF6B were genotyped and statistically analyzed in 93 AERD patients and 96 aspirin-tolerant asthma (ATA) as controls. RESULTS: Logistic analysis revealed that 2 SNPs (rs2228628 and rs8111, P=0.008; corrected P=0.03) and 1 haplotype (ATF6B-ht4, P=0.005; corrected P=0.02) were significantly associated with % decline of FEV1 by aspirin provocation, whereas ATF6B polymorphisms and haplotypes were not associated with the risk of AERD. CONCLUSIONS: Although further functional and replication studies are needed, our preliminary findings suggest that ATF6B may be related to obstructive phenotypes in response to aspirin exposure in adult asthmatics.