BAG3 promotes proliferation and migration of arterial smooth muscle cells by regulating STAT3 phosphorylation in diabetic vascular remodeling.

BACKGROUND: Diabetic vascular remodeling is the most important pathological basis of diabetic cardiovascular complications. The accumulation of advanced glycation end products (AGEs) caused by elevated blood glucose promotes the proliferation and migration of vascular smooth muscle cells (VSMCs), leading to arterial wall thickening and ultimately vascular remodeling. Therefore, the excessive proliferation and migration of VSMCs is considered as an important therapeutic target for vascular remodeling in diabetes mellitus. However, due to the lack of breakthrough in experiments, there is currently no effective treatment for the excessive proliferation and migration of VSMCs in diabetic patients. Bcl-2-associated athanogene 3 (BAG3) protein is a multifunctional protein highly expressed in skeletal muscle and myocardium. Previous research has confirmed that BAG3 can not only regulate cell survival and apoptosis, but also affect cell proliferation and migration. Since the excessive proliferation and migration of VSMCs is an important pathogenesis of vascular remodeling in diabetes, the role of BAG3 in the excessive proliferation and migration of VSMCs and its molecular mechanism deserve further investigation. METHODS: In this study, BAG3 gene was manipulated in smooth muscle to acquire SM22αCre; BAG3FL/FL mice and streptozotocin (STZ) was used to simulate diabetes. Expression of proteins and aortic thickness of mice were detected by immunofluorescence, ultrasound and hematoxylin-eosin (HE) staining. Using human aorta smooth muscle cell line (HASMC), cell viability was measured by CCK-8 and proliferation was measured by colony formation experiment. Migration was detected by transwell, scratch experiments and Phalloidin staining. Western Blot was used to detect protein expression and Co-Immunoprecipitation (Co-IP) was used to detect protein interaction. RESULTS: In diabetic vascular remodeling, AGEs could promote the interaction between BAG3 and signal transducer and activator of transcription 3 (STAT3), leading to the enhanced interaction between STAT3 and Janus kinase 2 (JAK2) and reduced interaction between STAT3 and extracellular signal-regulated kinase 1/2 (ERK1/2), resulting in accumulated p-STAT3(705) and reduced p-STAT3(727). Subsequently, the expression of matrix metallopeptidase 2 (MMP2) is upregulated, thus promoting the migration of VSMCs. CONCLUSIONS: BAG3 upregulates the expression of MMP2 by increasing p-STAT3(705) and decreasing p-STAT3(727) levels, thereby promoting vascular remodeling in diabetes. This provides a new orientation for the prevention and treatment of diabetic vascular remodeling.

Dissecting genetic architecture of rare dystonia: genetic, molecular and clinical insights.

BACKGROUND: Dystonia is one of the most common movement disorders. To date, the genetic causes of dystonia in populations of European descent have been extensively studied. However, other populations, particularly those from the Middle East, have not been adequately studied. The purpose of this study is to discover the genetic basis of dystonia in a clinically and genetically well-characterised dystonia cohort from Turkey, which harbours poorly studied populations. METHODS: Exome sequencing analysis was performed in 42 Turkish dystonia families. Using co-expression network (CEN) analysis, identified candidate genes were interrogated for the networks including known dystonia-associated genes and genes further associated with the protein-protein interaction, animal model-based characteristics and clinical findings. RESULTS: We identified potentially disease-causing variants in the established dystonia genes (PRKRA, SGCE, KMT2B, SLC2A1, GCH1, THAP1, HPCA, TSPOAP1, AOPEP; n=11 families (26%)), in the uncommon forms of dystonia-associated genes (PCCB, CACNA1A, ALDH5A1, PRKN; n=4 families (10%)) and in the candidate genes prioritised based on the pathogenicity of the variants and CEN-based analyses (n=11 families (21%)). The diagnostic yield was found to be 36%. Several pathways and gene ontologies implicated in immune system, transcription, metabolic pathways, endosomal-lysosomal and neurodevelopmental mechanisms were over-represented in our CEN analysis. CONCLUSIONS: Here, using a structured approach, we have characterised a clinically and genetically well-defined dystonia cohort from Turkey, where dystonia has not been widely studied, and provided an uncovered genetic basis, which will facilitate diagnostic dystonia research.

MiR-181a protects the heart against myocardial infarction by regulating mitochondrial fission via targeting programmed cell death protein 4.

Worldwide, myocardial infarction (MI) is the leading cause of death and disability-adjusted life years lost. Recent researches explored new methods of detecting biomarkers that can predict the risk of developing myocardial infarction, which includes identifying genetic markers associated with increased risk. We induced myocardial infarction in mice by occluding the left anterior descending coronary artery and performed TTC staining to assess cell death. Next, we performed ChIP assays to measure the enrichment of histone modifications at the promoter regions of key genes involved in mitochondrial fission. We used qPCR and western blot to measure expression levels of relative apoptotic indicators. We report that miR-181a inhibits myocardial ischemia-induced apoptosis and preserves left ventricular function after MI. We show that programmed cell death protein 4 (PDCD4) is the target gene involved in miR-181a-mediated anti-ischemic injury, which enhanced BID recruitment to the mitochondria. In addition, we discovered that p53 inhibits the expression of miR-181a via transcriptional regulation. Here, we discovered for the first time a mitochondrial fission and apoptosis pathway which is controlled by miR-181a and involves PDCD4 and BID. This pathway may be controlled by p53 transcriptionally, and we presume that miR-181a may lead to the discovery of new therapeutic and preventive targets for ischemic heart diseases.

In silico design of potential Mcl-1 peptide-based inhibitors.

CONTEXT: BIM (Bcl-2 interacting mediator of apoptosis)-derived peptides that specifically target over-expressed Mcl-1 (myeloid cell leukemia-1) protein and induce apoptosis are potentially anti-cancer agents. Since the helicity of BIM-derived peptides has a crucial role in their functionality, a range of strategies have been used to increase the helicity including the introduction of unnatural residues and stapling methods that have some drawbacks such as the accumulation in the liver. To avoid these drawbacks, this study aimed to design a more helical peptide by utilizing bioinformatics algorithms and molecular dynamics simulations without exploiting unnatural residues and stapling methods. MM-PBSA results showed that the mutations of A4fE and A2eE in analogue 5 demonstrate a preference towards binding with Mcl-1. As evidenced by Circular dichroism results, the helicity increases from 18 to 34%, these findings could enhance the potential of analogue 5 as an anti-cancer agent targeting Mcl-1. The applied strategies in this research could shed light on the in silico peptide design. Moreover, analogue 5 as a drug candidate can be evaluated in vitro and in vivo studies. METHODS: The sequence of the lead peptide was determined using the ApInAPDB database and PRALINE program. Contact finder and PDBsum web server softwares were used to determine the contact involved amino acids in complex with Mcl-1. All identified salt bridge contributing residues were unaltered to preserve the binding affinity. After proposing novel analogues, their secondary structures were predicted by Cham finder web server software and GOR, Neural Network, and Chou-Fasman algorithms. Finally, molecular dynamics simulations run for 100 ns were done using the GROMACS, version 5.0.7, with the CHARMM36 force field. MM-PBSA was used to assess binding affinity specificity in targeting Mcl-1 and Bcl-xL (B-cell lymphoma extra-large).

PDCD4 deficiency improved 4-vinylcyclohexene dioxide-induced mouse premature ovarian insufficiency.

RESEARCH QUESTION: What role does programmed cell death 4 (PDCD4) play in premature ovarian insufficiency (POI)? DESIGN: A PDCD4 gene knockout (PDCD4-/-) mouse model was constructed, a POI mouse model was established similar to human POI with 4-vinylcyclohexene dioxide (VCD), a PDCD4-overexpressed adenovirus was designed and the regulatory role in POI in vitro and in vivo was investigated. RESULTS: PDCD4 expression was significantly increased in the ovarian granulosa cells of patients with POI (P ≤ 0.002 protein and mRNA) and mice with VCD-induced POI (P < 0.001 protein expression in both mouse ovaries and granulosa cells). In POI-induced mice model, PDCD4 knockouts significantly increased anti-Müllerian hormone, oestrodiol and numbers of developing follicles, and the PI3K-AKT-Bcl2/Bax signalling pathway is involved in it. CONCLUSION: The expression and regulation of PDCD4 significantly affects the POI pathology in a mouse model. This effect is closely related to the regulation of Bcl2/Bax and the activation of the PI3K-AKT signalling pathway.

The role of the C-terminal tail region as a plug to regulate XKR8 lipid scramblase.

XK-related 8 (XKR8), in complex with the transmembrane glycoprotein basigin, functions as a phospholipid scramblase activated by the caspase-mediated cleavage or phosphorylation of its C-terminal tail. It carries a putative phospholipid translocation path of multiple hydrophobic and charged residues in the transmembrane region. It also has a crucial tryptophan at the exoplasmic end of the path that regulates its scrambling activity. We herein investigated the tertiary structure of the human XKR8-basigin complex embedded in lipid nanodiscs at an overall resolution of 3.66 Å. We found that the C-terminal tail engaged in intricate polar and van der Waals interactions with a groove at the cytoplasmic surface of XKR8. These interactions maintained the inactive state of XKR8. Point mutations to disrupt these interactions strongly enhanced the scrambling activity of XKR8, suggesting that the activation of XKR8 is mediated by releasing the C-terminal tail from the cytoplasmic groove. We speculate that the cytoplasmic tail region of XKR8 functions as a plug to prevent the scrambling of phospholipids.

Roles and signaling pathways of CITED1 in tumors: overview and novel insights.

CBP/p300 interacting transactivator with Glu/Asp-rich carboxy-terminal domain 1 (CITED1) is a transcriptional activator belonging to the non-DNA-binding transcription co-regulator family. It regulates diverse pathways, including the transforming growth factor/bone morphogenetic protein/SMAD, estrogen, Wnt-ß-catenin, and androgen-AR signaling pathways, by binding to CBP/p300 co-activators through its conserved transactivation domain CR2. CITED1 plays an important role in embryonic development and a certain regulatory role in the occurrence and development of various tumors. In this article, the biological characteristics, expression regulation, participating signaling pathways, and potential roles of CITED1 in the clinical diagnosis and treatment of tumors are reviewed.

Large-Scale Screening: Phenotypic and Mutational Spectrum in Isolated and Combined Dystonia Genes.

BACKGROUND: Pathogenic variants in several genes have been linked to genetic forms of isolated or combined dystonia. The phenotypic and genetic spectrum and the frequency of pathogenic variants in these genes have not yet been fully elucidated, neither in patients with dystonia nor with other, sometimes co-occurring movement disorders such as Parkinson's disease (PD). OBJECTIVES: To screen >2000 patients with dystonia or PD for rare variants in known dystonia-causing genes. METHODS: We screened 1207 dystonia patients from Germany (DysTract consortium), Spain, and South Korea, and 1036 PD patients from Germany for pathogenic variants using a next-generation sequencing gene panel. The impact on DNA methylation of KMT2B variants was evaluated by analyzing the gene's characteristic episignature. RESULTS: We identified 171 carriers (109 with dystonia [9.0%]; 62 with PD [6.0%]) of 131 rare variants (minor allele frequency <0.005). A total of 52 patients (48 dystonia [4.0%]; four PD [0.4%, all with GCH1 variants]) carried 33 different (likely) pathogenic variants, of which 17 were not previously reported. Pathogenic biallelic variants in PRKRA were not found. Episignature analysis of 48 KMT2B variants revealed that only two of these should be considered (likely) pathogenic. CONCLUSION: This study confirms pathogenic variants in GCH1, GNAL, KMT2B, SGCE, THAP1, and TOR1A as relevant causes in dystonia and expands the mutational spectrum. Of note, likely pathogenic variants only in GCH1 were also found among PD patients. For DYT-KMT2B, the recently described episignature served as a reliable readout to determine the functional effect of newly identified variants. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Multifaceted roles of CCAR family proteins in the DNA damage response and cancer.

The cell cycle apoptosis regulator (CCAR) family of proteins consists of two proteins, CCAR1 and CCAR2, that play a variety of roles in cellular physiology and pathology. These multidomain proteins are able to perform multiple interactions and functions, playing roles in processes such as stress responses, metabolism, and the DNA damage response. The evolutionary conservation of CCAR family proteins allows their study in model organisms such as Caenorhabditis elegans, where a role for CCAR in aging was revealed. This review particularly highlights the multifaceted roles of CCAR family proteins and their implications in the DNA damage response and in cancer biology.

Generation of CRISPR-Cas9 edited human induced pluripotent stem cell line carrying BAG3 V468M mutation in its BAG domain.

BCL2-Associated Athanogene 3 (BAG3) gene was identified mutated in patients with dilated cardiomyopathy (DCM), an important cause of heart failure and premature death. BAG3 is a cytoprotective co-chaperonne protein involved in many cellular process with a central role in the maintenance of protostasis. We generated two human induced pluripotent stem cell lines (hiPSc), one carrying the heterozygous, the other the homozygous p.V468M mutation identified in DCM familial cases. All lines expressed pluripotent markers, had normal karyotype, and differentiated into derivatives of the three germ layers. Sudies of hiPSc derived cardiomyocytes will help to understand the role of BAG3 in DCM.

A peptide encoded by the circular form of the SHPRH gene induces apoptosis in neuroblastoma cells.

Background: Circular RNAs (circRNAs) and their derived peptides represent largely unchartered areas in cellular biology, with many potential roles yet to be discovered. This study aimed to elucidate the role and molecular interactions of circSHPRH and its peptide derivative SHPRH-146aa in the pathogenesis of neuroblastoma (NB). Methods: NB samples in the GSE102285 dataset were analyzed to measure circSHPRH expression, followed by in vitro experiments for validation. The role of SHPRH-146aa in NB cell proliferation, migration, and invasion was then examined, and luciferase activity assay was performed after SHPRH-146aa and RUNX1 transfection. Finally, the regulation of NB cell apoptosis by SHPRH-146aa combined with NFKBIA was tested. Results: The GSE102285 dataset indicated overexpression of circSHPRH in NB samples, further supported by in vitro findings. Overexpression of circ-SHPRH and SHPRH-146aa inhibited proliferation, migration, and invasion of NB cells. A significant increase in apoptosis was observed, with upregulation of Caspase-3 and downregulation of Bcl-2. Furthermore, the peptide derivative SHPRH-146aa, derived from circSHPRH, suppressed NB cell malignancy traits, suggesting its role as a therapeutic target. A direct interaction between SHPRH-146aa and the transcription factor RUNX1 was identified, subsequently leading to increased NFKBIA expression. Notably, NFKBIA knockdown inhibited the pro-apoptotic effect of SHPRH-146aa on NB cells. Conclusion: The study demonstrates that circ-SHPRH and SHPRH-146aa play significant roles in inhibiting the malignant progression of NB. They induce apoptosis primarily by modulating key apoptotic proteins Caspase-3 and Bcl-2, a process that appears to be regulated by NFKBIA. The SHPRH-146aa-RUNX1 interaction further elucidates a novel pathway in the regulation of apoptosis in NB. These findings indicate that circ-SHPRH and its derived peptide SHPRH-146aa could be potential therapeutic targets for NB treatment.

Cerebral cavernous malformation proteins, CCM1, CCM2 and CCM3, are decreased in metastatic lesions in a murine breast carcinoma model.

Three genes are associated with cerebral cavernous malformations (CCMs): CCM1, CCM2 and CCM3. These genes participate in microvascular angiogenesis, cell-to-cell junctions, migration and apoptosis. We evaluated the expression in vivo of CCM genes in primary tumors and metastastases in a murine model of metastatic breast carcinoma. We used cell lines obtained from metastasis of 4T1, 4TLM and 4THM breast cancer to liver and heart. These cells were injected into the mammary ridge of Balb/C female mice. After 27 days, the primary tumors, liver and lung were removed and CCM proteins were assessed using immunohistochemistry and western blot analysis. CCM proteins were expressed in primary tumor tissues of all tumor-injected animals; however, no CCM protein was expressed in metastatic tumor cells that migrated into other tissues. CCM proteins still were observed in the lung and liver tissue cells. Our findings suggest that CCM proteins are present during primary tumor formation, but when these cells develop metastatic potential, they lose CCM protein expression. CCM protein expression was lost or reduced in metastatic tissues compared to the primary tumor, which indicates that CCM proteins might participate in tumorigenesis and metastasis.

Maturity-onset Diabetes of the Young Type 7 (MODY7) and the Krüppellike Factor 11 Mutation (KLF11). A Review.

INTRODUCTION: Maturity-onset diabetes of the young (MODY) is a rare disease due to a single gene mutation that affects several family members in most cases. The Krüppel-like factor 11 (KLF11) gene mutation is associated with decreased insulin sensitivity to high glucose levels. KLF 11 has been implicated in the pathogenesis of MODY type 7 but given its low prevalence, prolonged subclinical period, and the emergence of new information, doubts are raised about its association. METHODS: A literature search of the PubMed, Scopus, and EBSCO databases was performed. The terms "Diabetes Mellitus, Type 2/genetics", "Mason-Type Diabetes" , "Maturity-Onset diabetes of the young", "KLF11 protein, human", and "Maturity-Onset Diabetes of the Young, Type 7" were used"., "Diagnosis" The search selection was not standardized. RESULTS: The KLF1 mutation is rare and represents <1% of the mutations associated with monogenic diabetes. Its isolation in European family lines in the first studies and the emergence of new variants pose new diagnostic challenges. This article reviews the definition, epidemiology, pathophysiology, diagnosis, and treatment of MODY type 7. CONCLUSION: MODY type 7 diabetes represents a rare form of monogenic diabetes with incomplete penetrance. Given its rarity, its association with impaired glucose metabolism has been questioned. Strict evaluation of glycemic control and the appearance of microvascular complications are key areas in the follow-up of patients diagnosed with MODY 7. More studies will be required to characterize the population with KLF11 mutation and clarify its correlation with MODY.

Distal hereditary motor neuronopathy as a new phenotype associated with variants in BAG3.

OBJECTIVE: To describe a new phenotype associated with a novel variant in BAG3: autosomal dominant adult-onset distal hereditary motor neuronopathy. METHODS: This study enrolled eight affected individuals from a single family and included a comprehensive evaluation of the clinical phenotype, neurophysiologic testing, muscle MRI, muscle biopsy and western blot of BAG3 protein in skeletal muscle. Genetic workup included whole exome sequencing and segregation analysis of the detected variant in BAG3. RESULTS: Seven patients developed slowly progressive and symmetric distal weakness and atrophy of lower limb muscles, along with absent Achilles reflexes. The mean age of onset was 46 years. The neurophysiological examination was consistent with the diagnosis of distal motor neuronopathy. One 57-year-old female patient was minimally symptomatic. The pattern of inheritance was autosomal dominant, with one caveat: one female patient who was an obligate carrier of the variant died at the age of 73 years without exhibiting any muscle weakness. The muscle biopsies revealed neurogenic changes. A novel heterozygous truncating variant c.1513_1514insGGAC (p.Val505GlyfsTer6) in the gene BAG3 was identified in all affected family members. CONCLUSIONS: We report an autosomal dominant adult-onset distal hereditary motor neuronopathy with incomplete penetrance in women as a new phenotype related to a truncating variant in the BAG3 gene. Our findings expand the phenotypic spectrum of BAG3-related disorders, which previously included dilated cardiomyopathy, myofibrillar myopathy and adult-onset Charcot-Marie-Tooth type 2 neuropathy. Variants in BAG3 should be considered in the differential diagnosis of distal hereditary motor neuronopathies.

Impact of TP53-induced glycolysis and apoptosis regulator on malignant activity and resistance to ferroptosis in intrahepatic cholangiocarcinoma.

TP53-induced glycolysis and apoptosis regulator (TIGAR) is an important gene that encodes a regulatory enzyme of glycolysis and reactive oxygen species (ROS) detoxification and is associated with worse prognosis in various cancers. Ferroptosis is a recently identified type of programmed cell death that is triggered by iron-dependent lipid peroxidation. There are no reports on the prognostic impact of TIGAR on intrahepatic cholangiocarcinoma (ICC), and its role in ferroptosis is unclear. Ninety ICC patients who had undergone hepatic resection were enrolled. Immunohistochemical staining for TIGAR was performed. The regulation of malignant activity by TIGAR and the association between ferroptosis and TIGAR were investigated in vitro. Twenty-two (24.4%) patients were categorized into TIGAR-high and -low groups by immunohistochemical staining. There were no noticeable differences in background factors between the two groups, but TIGAR positivity was an independent prognostic factor in disease-free survival (hazard ratio [HR], 2.00; 95% confidence interval [CI], 1.04-3.85, p = 0.0378) and overall survival (HR, 2.10; 95% CI, 1.03-4.30, p = 0.00422) in a multivariate analysis. In vitro, TIGAR knockdown (KD) decreased cell motility (cell proliferation/migration/invasion/colony-forming capabilities) and elevated ROS and lipid peroxidation. This indicated that TIGAR KD induced ferroptosis. TIGAR KD-induced ferroptosis was suppressed using liproxstatin. TIGAR KD decreased the expression of glutathione peroxidase 4, known as factor-suppressing ferroptosis. The combination of TIGAR KD with cisplatin significantly induced more ferroptosis. In conclusion, TIGAR is associated with poor outcomes in ICC patients and resistance to ferroptosis.

WWP2 binds to NKRF, enhances the NF-κB signaling, and promotes malignant phenotypes of acute myeloid leukemia cells.

Acute myeloid leukemia (AML) is one of the hematological malignancies with a high recurrence rate. WW domain-containing E3 ubiquitin protein ligase 2 (WWP2) is identified as a pivotal regulator of tumor progression. This study aimed to assess the possible role of WWP2 in AML. Analysis of the GEPIA database indicated an elevated WWP2 expression in AML. We established stable WWP2-overexpressed or WWP2-silenced cells using lentivirus loaded with cDNA encoding WWP2 mRNA or shRNA targeting WWP2. Notably, WWP2 overexpression facilitated cell proliferation and cell cycle progression, which was manifested as the increase of colony formation number, S-phase percentage and cell cycle related protein levels. As observed, WWP2 knockdown presented opposite effects, leading to inhibition of tumorigenicity. Strikingly, WWP2 knockdown induced apoptosis, accompanied by upregulation of pro-apoptosis proteins cleaved caspase-9, Bax and cleaved caspase-3 and downregulation of anti-apoptosis protein Bcl-2. Functionally, we further confirmed that WWP2 overexpression enhanced the NF-κB signaling and upregulated the levels of downstream genes, which may contribute to aggravating the development of AML. More importantly, by co-immunoprecipitation assay, we verified that WWP2 bound to NF-κB-repressing factor (NKRF) and promoted NKRF ubiquitylation. Dramatically, NKRF overexpression abolished the role of WWP2 in facilitating the process of AML. Overall, our observations confirm that WWP2 exerts a critical role in the tumorigenicity of AML, and NKRF is regarded as an essential factor in the WWP2-mediated AML progression. WWP2 may be proposed as a promising target of AML.

The mechanism of anticancer effects of some pyrrolopyrimidine derivatives on HT-29 human colon cancer cells.

In the present work, the mechanism of anticancer activity of some pyrrolopyrimidine derivatives was evaluated. Compounds 5 and 8 exhibiting significant antiproliferative activity against HT-29 cells with IC50 values of 4.17 µM and 2.96, arrested the cells at the G2/M phase and significantly induced apoptosis. The apoptotic potential of the compounds has been verified via ELISA assay, which resulted in increased BAX, PUMA, BIM, and cleaved caspase 3 expression and decreased BCL-XL and MCL-1 protein levels in HT-29 cells. Moreover, the immunofluorescence technique showing that compounds 5 and 8-treatment reduced Ki67 immunolocalization and increased the caspase 3 and p53 immunolocalization confirmed the apoptotic activity. While treatment of HT-29 cells to compounds 5 and 8 inhibited Akt and ERK1/2, there are no alterations in JNK and p38 signaling pathways. According to molecular docking results, compounds 5 and 8 occupied the active site of Akt kinase and showed important hydrogen bonding interactions with key amino acids. Also, siRNA-mediated depletion of BIM, PUMA, and BAX/BAK expression decreased apoptotic response in HT-29 cells upon exposure to compound 5 and compound 8. Compounds 5 and 8 trigger the activation of mitochondrial apoptosis in HT-29 cells. Additionally, we found that proapoptotic BH3-only proteins BIM and PUMA are required for the full engagement of mitochondrial apoptosis signaling. However, p53 was dispensable for compound 5- or compound 8-induced apoptosis in HT-29 cells.

Hsp70-Bim incoherent feedforward loop contributes to cell-fate heterogeneity and fractional killing.

BACKGROUND AND PURPOSE: Although chemotherapeutics or molecular targeted drugs often elicit profound initial responses, fractional killing capable of driving acquired resistance can persist. Identifying stress-induced negative feedback or an incoherent feedforward loop (IFFL), which may contribute to fractional killing, is urgently needed. EXPERIMENTAL APPROACH: Mathematical modelling was used to identify how and to what extent a recently reported Hsp70-Bim protein-protein interaction (PPI) contributes to the adaptation of the Bcl-2 network. Experimental validation was made by using a specific inhibitor of Hsp70-Bim PPI, S1g-2, as chemical tool. Bifurcation analysis and stochastic simulation were used for the theoretical study of the impact of Hsp70-Bim PPI on cell-fate heterogeneity and factional killing. KEY RESULTS: The Hsp70-Bim-AKT circuit forms an IFFL that greatly contributes to the adaptation of the Bcl-2-regulated apoptosis network, thus leading to fractional killing. This adaptive programme enhances noise-induced cell-fate heterogeneity by shifting from a saddle-node to a saddle-collision transition scenario. CONCLUSION AND IMPLICATIONS: Hsp70-Bim IFFL serves as a molecular pathway induced by DNA damaging drugs or tyrosine kinase inhibitors that enabled fractional killing, whereby acquired resistance emerges. A synergistic strategy is unveiled for overcoming fractional killing by suppressing Hsp70-Bim PPI.

Combined absence of TRP53 target genes ZMAT3, PUMA and p21 cause a high incidence of cancer in mice.

Transcriptional activation of target genes is essential for TP53-mediated tumour suppression, though the roles of the diverse TP53-activated target genes in tumour suppression remains poorly understood. Knockdown of ZMAT3, an RNA-binding zinc-finger protein involved in regulating alternative splicing, in haematopoietic cells by shRNA caused leukaemia only with the concomitant absence of the PUMA and p21, the critical effectors of TRP53-mediated apoptosis and cell cycle arrest respectively. We were interested to further investigate the role of ZMAT3 in tumour suppression beyond the haematopoietic system. Therefore, we generated Zmat3 knockout and compound gene knockout mice, lacking Zmat3 and p21, Zmat3 and Puma or all three genes. Puma-/-p21-/-Zmat3-/- triple knockout mice developed tumours at a significantly higher frequency compared to wild-type, Puma-/-Zmat3-/- or p21-/-Zmat3-/-deficient mice. Interestingly, we observed that the triple knockout and Puma-/-Zmat3-/- double deficient animals succumbed to lymphoma, while p21-/-Zmat3-/- animals developed mainly solid cancers. This analysis suggests that in addition to ZMAT3 loss, additional TRP53-regulated processes must be disabled simultaneously for TRP53-mediated tumour suppression to fail. Our findings reveal that the absence of different TRP53 regulated tumour suppressive processes changes the tumour spectrum, indicating that different TRP53 tumour suppressive pathways are more critical in different tissues.

Identification of novel rare variants for anxiety: an exome-wide association study in the UK Biobank.

BACKGROUND: Rare variants are believed to play a substantial role in the genetic architecture of mental disorders, particularly in coding regions. However, limited evidence supports the impact of rare variants on anxiety. METHODS: Using whole-exome sequencing data from 200,643 participants in the UK Biobank, we investigated the contribution of rare variants to anxiety. Firstly, we computed genetic risk score (GRS) of anxiety utilizing genotype data and summary data from a genome-wide association study (GWAS) on anxiety disorder. Subsequently, we identified individuals within the lowest 50% GRS, a subgroup more likely to carry pathogenic rare variants. Within this subgroup, we classified individuals with the highest 10% 7-item Generalized Anxiety Disorder scale (GAD-7) score as cases (N = 1869), and those with the lowest 10% GAD-7 score were designated as controls (N = 1869). Finally, we conducted gene-based burden tests and single-variant association analyses to assess the relationship between rare variants and anxiety. RESULTS: Totally, 47,800 variants with MAF ≤0.01 were annotated as non-benign coding variants, consisting of 42,698 nonsynonymous SNVs, 489 nonframeshift substitution, 236 frameshift substitution, 617 stop-gain and 40 stop-loss variants. After variation aggregation, 5066 genes were included in gene-based association analysis. Totally, 11 candidate genes were detected in burden test, such as RNF123 (PBonferroni adjusted = 3.40 × 10-6), MOAP1(PBonferroni adjusted = 4.35 × 10-4), CCDC110 (PBonferroni adjusted = 5.83 × 10-4). Single-variant test detected 9 rare variants, such as rs35726701(RNF123)(PBonferroni adjusted = 3.16 × 10-10) and rs16942615(CAMTA2) (PBonferroni adjusted = 4.04 × 10-4). Notably, RNF123, CCDC110, DNAH2, and CSKMT gene were identified in both tests. CONCLUSIONS: Our study identified novel candidate genes for anxiety in protein-coding regions, revealing the contribution of rare variants to anxiety.