Downstream Target Research Articles

Exploring the Dual Role of MALAT1 in Thyroid Tumorigenesis: Oncogenic or Tumor Suppressor?

Thyroid cancer is the most prevalent form of endocrine cancer. Therefore, the administration of new therapeutic agents for thyroid cancer patients is necessary. One of the recent successes in thyroid cancer research is the identification of the role of signaling pathways in the pathogenesis of the disease. Emerging evidence reveals that long non-coding RNAs (lncRNAs) can serve as novel therapeutic approaches for the diagnosis and treatment of thyroid cancer. The lncRNA metastasis-associated lung adenocarcinoma transcript-1 (MALAT1) plays key roles in gene expression, RNA processing, and epigenetic regulation. It is believed that MALAT1 can regulate several cancer-related processes, including tumour cell growth, proliferation, and metastasis. MALAT1 is involved in the pathogenesis of thzroid cancers by targeting multiple downstream targets and miRNA/mRNA axes. Here, we summarize the emerging roles of MALAT1 in this cancer.

HPV16 integration regulates ferroptosis resistance via the c-Myc/miR-142-5p/HOXA5/SLC7A11 axis during cervical carcinogenesis

BackgroundFerroptosis, a newly identified form of regulated cell death triggered by small molecules or specific conditions, plays a significant role in virus-associated carcinogenesis. However, whether tumours arising after high-risk HPV integration are associated with ferroptosis is unexplored and remains enigmatic.MethodsHigh-risk HPV16 integration was analysed by high­throughput viral integration detection (HIVID). Ferroptosis was induced by erastin, and the levels of ferroptosis were assessed through the measurement of lipid-reactive oxygen species (ROS), malondialdehyde (MDA), intracellular Fe2+ level and transmission electron microscopy (TEM). Additionally, clinical cervical specimens and an in vivo xenograft model were utilized for the study.ResultsExpression of HPV16 integration hot spot c-Myc negatively correlates with ferroptosis during the progression of cervical squamous cell carcinoma (CSCC). Further investigation revealed that the upregulated oncogene miR-142-5p in HPV16-integrated CSCC cells served as a critical downstream effector of c-Myc in its target network. Inhibiting miR-142-5p significantly decreased the ferroptosis-suppressing effect mediated by c-Myc. Through a combination of computational and experimental approaches, HOXA5 was identified as a key downstream target gene of miR-142-5p. Overexpression of miR-142-5p suppressed HOXA5 expression, leading to decreased accumulation of intracellular Fe2+ and lipid peroxides (ROS and MDA). HOXA5 increased the sensitivity of CSCC cells to erastin-induced ferroptosis via transcriptional downregulation of SLC7A11, a negative regulator of ferroptosis. Importantly, c-Myc knockdown increased the anti-tumour activity of erastin by promoting ferroptosis both in vitro and in vivo.ConclusionsCollectively, these data indicate that HPV16 integration hot spot c-Myc plays a novel and indispensable role in ferroptosis resistance by regulating the miR-142-5p/HOXA5/SLC7A11 signalling axis and suggest a potential therapeutic approach for HPV16 integration-related CSCC.

Downregulation of hsa_circ_0006620 inhibits the malignant progression of prostate cancer by regulation of the miR-502-3p/HK2 axis mediated by aerobic glycolysis.

Circular RNAs (circRNA) are a class of covalently-closed, single-stranded RNAs that have been implicated in cancer progression due to their regulation of metabolism. However, the roles of circRNA in prostate cancer remain largely unknown. In this study, fluorescence in situ hybridization and RT-qPCR were used to investigate hsa_circ_0006620 expressions in both prostate cancer cells and tissues, after high-throughput sequencing. The luciferase reporter assay was used to identify hsa_circ_0006620 downstream targets. Transwell migration assays, 5-ethynyl-20-deoxyuridine assays, and Cell Counting Kit-8assays were used to investigate both proliferation and migration. In vivo tumorigenesis and metastasis assays were performed to investigate the role of hsa_circ_0006620 in prostate cancer. The results showed that hsa_circ_0006620 expression increased in prostate cancer cells and tissues. Hsa_circ_0006620 downregulation inhibited prostate cancer cell proliferation as well as in vivo and in vitro migrations. The luciferase results validated that miR-502-3p and hexokinase 2 (HK2) were hsa_circ_0006620 downstream targets. HK2 overexpression or miR-502-3p inhibition reversed prostate cancer cell migration after hsa_circ_0006620 silencing. The study also found that overexpression of HK2 or inhibition of prostate cancer reversed aerobic glycolysis after hsa_circ_0006620 silencing. In summary, the results showed thathsa_circ_0006620 downregulation inhibited prostate cancerby regulation of the miR-502-3p/HK2 axis mediated by aerobic glycolysis.

TME-responsive nanoplatform for multimodal imaging-guided synergistic precision therapy of esophageal cancer via inhibiting HIF-1α signal pathway

Esophageal cancer (EC) is the sixth leading cause of cancer-related deaths, and its treatment poses significant challenges. In recent years, photodynamic, photothermal, and chemodynamic therapies have emerged as alternative strategies for tumor intervention. However, limitations such as poor tumor targeting, insufficient microenvironment responsiveness, and unclear mechanisms hinder their application. In this study, we found that hypoxia-inducible factor 1 alpha (HIF-1α) was highly expressed in clinical EC samples, which contributed to tumor malignancy and metastasis. We developed a carbon dots (CDs)-based tumor microenvironment (TME)-responsive nanoplatform, CDs-MnO2-Au-Cet (CMAC), designed for multimodal imaging-guided precision therapy in EC. Both in vitro and in vivo experiments demonstrated that CMAC effectively targeted and imaged EC cells and tissues. CMAC significantly inhibited tumor growth by inducing apoptosis and reducing lung metastasis. Mechanistically, CMAC administration led to a substantial downregulation of HIF-1α and its downstream targets, GLUT1 and MMP9. In summary, we presented a novel nanoplatform for imaging-guided synergistic therapy in EC, which demonstrated excellent anti-tumor growth and metastasis capabilities, along with favorable biocompatibility. This study laid the groundwork for developing innovative theranostic strategies for EC.

UBC18 E2 conjugating enzyme depends on SINAT1 E3 ligase to destabilize the ESCRT component FREE1 in plant iron deficiency responses.

E2 ubiquitin-conjugating enzymes play a crucial role in the ubiquitination process by catalyzing ubiquitin transfer. Although the function of ubiquitin-protein ligases (E3s) in plants response to diverse abiotic stress by targeting specific substrates has been well studied, the involvement of E2s in environmental responses and their downstream targets are not well understood. In this study, we demonstrated that the E2 ubiquitin-conjugating enzyme 18 (UBC18) influences the stability of FREE1 to modulate iron deficiency stress. UBC18 affects the ubiquitination of FREE1 and promotes its degradation, and overexpression of UBC18 decreases plants' sensitivity to iron deficiency by reducing FREE1 level, whereas the ubc18 mutant exhibits sensitivity due to elevated FREE1 accumulation. This study also identified that lysine residues K227, K295, K315, and K540 are required for FREE1 ubiquitination and stability regulation. Mutating these lysine residues in FREE1 resulted in plants' sensitivity to iron starvation. Taken together, our findings shed light on the mechanism of UBC18 in responding to iron deficiency stress by modulating the abundance of FREE1, and further elucidate the role of ubiquitination sites in FREE1 stability regulation and the plant iron deficiency response.

The Induction of Drug Uptake Transporter Organic Anion Transporting Polypeptide 1A2 by Radiation Is Mediated by the Nonreceptor Tyrosine Kinase v-YES-1 Yamaguchi Sarcoma Viral Oncogene Homolog 1.

Organic anion transporting polypeptides (OATP, gene symbol SLCO) are well-recognized key determinants for the absorption, distribution, and excretion of a wide spectrum of endogenous and exogenous compounds including many antineoplastic agents. It was therefore proposed as a potential drug target for cancer therapy. In our previous study, it was found that low-dose X-ray and carbon ion irradiation both upregulated the expression of OATP family member OATP1A2 and in turn, led to a more dramatic killing effect when cancer cells were cotreated with antitumor drugs such as methotrexate. In the present study, the underlying mechanism of the phenomenon was explored in breast cancer cell line MCF-7. It was found that the nonreceptor tyrosine kinase v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1 (YES-1) was temporally coordinated with the change of OATP1A2 after irradiation. The overexpression of YES-1 significantly increased OATP1A2 both at the mRNA and protein level. The signal transducer and activator of transcription 3 (STAT3) pathway is likely the downstream target of YES-1 because phosphorylation and nuclear accumulation of STAT3 were both enhanced after overexpressing YES-1 in MCF-7 cells. Further investigation revealed that there are two possible binding sites of STAT3 localized at the upstream sequence of SLCO1A2, the encoding gene of OATP1A2. Electrophoretic mobility shift assay and chromatin immunoprecipitation analysis suggested that these two sites bound to STAT3 specifically and the overexpression of YES-1 significantly increased the association of the transcription factor with the putative binding sites. Finally, inhibition or knockdown of YES-1 attenuated the induction effect of radiation on the expression of OATP1A2. SIGNIFICANCE STATEMENT: The present study found that the effect of X-rays on v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1 (YES-1) and organic anion transporting polypeptides (OATP)1A2 was temporally coordinated. YES-1 phosphorylates and increases the nuclear accumulation of signal transducer and activator of transcription 3, which in turn binds to the upstream regulatory sequences of SLCO1A2, the coding gene for OATP1A2. Hence, inhibitors of YES-1 may suppress the radiation induction effect on OATP1A2.

Hypoxic glioma-derived exosomal miR-25-3p promotes macrophage M2 polarization by activating the PI3K-AKT-mTOR signaling pathway

BackgroundExosomes (EXO) play crucial roles in intercellular communication and glioma microenvironment modulation. Tumor-associated macrophages are more likely to become M2-like type macrophages in the immunosuppressive microenvironment. Here, we aimed to investigate the effects and molecular mechanisms of hypoxic glioma-derived exosomes mediated M2-like macrophage polarization.MethodsHighly expressed miRNAs in exosomes derived from glioma cells cultured under hypoxia condition compared to normoxic condition were identified through microRNA sequencing. The polarization status of macrophages was determined using qRT-PCR, Western blotting, flow cytometry, and immunohistochemistry. By using RNA-seq, we aimed to identify the downstream target genes regulated by miR-25-3p in macrophages and investigate the mechanistic pathways through which it exerts its effects. The proliferation and migration capabilities of glioma cells were assessed through EdU, Transwell assays, and in vivo experiments.ResultsWe found that miR-25-3p was upregulated in the exosomes derived from hypoxic glioma cells and can be transferred to the macrophage. In macrophages, miR-25-3p downregulates the expression of PHLPP2, thereby activating the PI3K-AKT-mTOR signaling pathway, ultimately leading to macrophage M2 polarization. As part of a feedback loop, M2-polarized macrophages can, in turn, promote malignant glioma progression.ConclusionOur study reveals that miR-25-3p from hypoxic glioma cells is delivered to macrophages via exosomes as a mediator, promoting M2 polarization of macrophages through the miR-25-3p/PHLPP2/PI3K-AKT signaling pathway. This study suggests that targeted interventions to modulate miR-25-3p expression, transmission, or inhibition of PI3K-AKT pathway activation can disrupt the immune-suppressive microenvironment, providing a novel approach for immunotherapy in gliomas.Graphical

Identifying HIF1A and HGF as two hub genes in aortic dissection and function analysis by integrating RNA sequencing and single-cell RNA sequencing data.

Aortic dissection (AD) is a severe aortic disease with high mortality, and its pathogenesis remains elusive. To explore the regulatory mechanisms of AD, we integrated public RNA sequencing (RNA-seq) and single-cell RNA sequencing (scRNA-seq) datasets to screen the hub genes of AD and further analyzed their functions, which may provide references to the diagnosis and treatment of AD. Four AD-related datasets were obtained from the Gene Expression Omnibus (GEO) database. Weighted gene co-expression network analysis and differential expression analysis were applied to identify overlapping genes in dataset GSE153434. Protein-protein interaction (PPI) network was constructed based on overlapping genes. Five methods (closeness, degree, EPC, MCC, and MNN) were used to pick hub genes. The receiver operating characteristic curve was used to evaluate the diagnostic efficiency of the hub genes in extra datasets GSE98770 and GSE52093. scRNA-seq dataset GSE213740 was used to explore the expression and function of the hub genes at the single-cell level. Quantitative real-time polymerase chain reaction was used to verify the expression of hub genes in beta-aminopropionitrile (BAPN)-induced mouse thoracic aortic aneurysm and dissection (TAAD) model. A total of 71 overlapping genes were screened by intersecting the significant genes in the pink module and the differentially expressed genes. A PPI network with 45 nodes and 74 edges was generated, and five top hub genes (HIF1A, HGF, HMOX1, ITGA5, and ITGB3) were identified. All the hub genes had area under the curve values above 0.55. scRNA-seq data analysis showed that HIF1A was significantly upregulated in macrophages and HGF was significantly upregulated in vascular smooth muscle cells (SMCs) of the ascending aortas in AD patients. HIF1A may transcriptionally regulate multiple downstream target genes involving inflammation (TLR2, ALOX5AP, and MIF), glycolysis (ENO1, LDHA, and GAPDH), tissue remodeling (PLAU), and angiogenesis (SERPIN and VEGFA). HGF may participate in the signaling among SMCs, fibroblasts, and endothelial cells through binding to different receptors (MET, EGFR, IGF1R, and KDR). The mRNA expression of Hif1a, Hgf, and their target genes, including Alox5ap, Serpine1, Tlr2, Plau, Egfr, and Igf1r, was significantly upregulated in aortic tissues of BAPN-treated mice. By integrating RNA-seq and scRNA-seq data, we identified HIF1A and HGF as two hub genes with good diagnostic efficiency for AD. HIF1A in macrophages may promote AD formation by promoting inflammation, glycolysis, tissue remodeling, and angiogenesis, and HGF may mediate signaling among SMCs, fibroblasts, and endothelial cells in the development of AD.

O-GlcNAcylation regulates osteoblast differentiation through the morphological changes in mitochondria, cytoskeleton, and endoplasmic reticulum.

To explore the potential mechanisms which O-linked-N-acetylglucosaminylation (O-GlcNAcylation) regulates osteogenesis, a publicly RNA-seq dataset was re-analyzed with literature-mining and showed the primary targets of O-GlcNAcylation in osteoblasts are mitochondria/cytoskeleton. Although the O-GlcNAcylation-regulated mitochondria/cytoskeleton has been extensively studied, its specific role during osteogenesis remains unclear. To address this, we knocked out Ogt (Ogt-KO) in MC3T3-E1 osteoblastic cells. Then, significantly reduced osteoblast differentiation, motility, proliferation, mitochondria-endoplasmic reticulum (Mito-ER) coupling, volume of ER, nuclear tubulins, and oxygen metabolism were observed in Ogt-KO cells. Through artificial intelligence (AI)-predicted cellular structures, the time-lapse live cells imaging with reactive-oxygen-species/hypoxia staining showed that lower cell proliferation and altered oxygen metabolism in the Ogt-KO cells were correlated with the Mito-ER coupling. Bioinformatics analysis, combined with correlated mRNA and protein expression, suggested that Ezh2 and its downstream targets (Opa1, Gsk3a, Wnt3a, Hif1a, and Hspa9) may be involved in O-GlcNAcylation-regulated Mito-ER coupling, ultimately impacting osteoblast differentiation. In conclusion, our findings indicate that O-GlcNAcylation-regulated osteoblast differentiation is linked to morphological changes in mitochondria, cytoskeleton, and ER, with Ezh2 potentially playing a crucial role.

MiR-21-5p Promotes Osteogenic Differentiation and Calcification of Valvular Interstitial Cells by Targeting TGFBI in Calcific Aortic Valve Disease.

Calcific aortic valve disease (CAVD) is the most common heart relating disease with high morbidity and mortality, especially in elderly population. While extensive investigations have been devoted to the study of mechanistic pathways related to CAVD, the key factors and mechanisms mediating valve mineralization remain unclear. The aim of this study is to investigate the role of mirnas and their downstream targets in CAVD disease progression. A previous recent multi-omics study suggested a novel CAVD molecular interaction network contained miR-21-5p. CAV and their pair-matched adjacent normal tissues were obtained from 15 patients pathologically diagnosed as CAVD and admitted in Yancheng Third People's Hospital (The Sixth Affiliated Hospital of Nantong University) from 2019-2021. RT-qPCR was utilized for detection of miR-21-5p and related protein expression levels to confirm the related factors in CAVD progression. Western blotting was applied to strengthen the results of RT-qPCR and confirm osteogenic differentiation of VICs via biomarker detection. The staining of alkaline phosphatase (ALP) and alizarin red was performed to assess the degree of VIC mineralization. We found that miR-21-5p was remarkably increased (P<0.0001) in calcified aortic valves (AVs) whereas TGFBI was diminished (P<0.01) in CAVD samples compared to the paired normal tissues from CAVD patients. Additionally, TGFBI was targeted by miR-21-5p. Furthermore, overexpressing TGFBI could block VIC osteogenic differentiation mediated by miR-21-5p. To sum up, miR-21-5p promotes VIC osteogenic differentiation and calcification via TGFBI in CAVD progression. Our work might bring a sight on underlying mechanisms of CAVD progression and provide a possible therapeutic target for diagnosis and treatment.

PSAT1 is upregulated by METTL3 to attenuate high glucose-induced retinal pigment epithelial cell apoptosis and oxidative stress

BackgroundDiabetic retinopathy (DR) is a major ocular complication of diabetes mellitus, and a significant cause of visual impairment and blindness in adults. Phosphoserine aminotransferase 1 (PSAT1) is an enzyme participating in serine synthesis, which might improve insulin signaling and insulin sensitivity. Furthermore, it has been reported that the m6A methylation in mRNA controls gene expression under many physiological and pathological conditions. Nevertheless, the influences of m6A methylation on PSAT1 expression and DR progression at the molecular level have not been reported.MethodsHigh-glucose (HG) was used to treat human retinal pigment epithelial cells (ARPE-19) to construct a cell injury model. PSAT1 and Methyltransferase-like 3 (METTL3) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). PSAT1, B-cell lymphoma-2 (Bcl-2), Bcl-2 related X protein (Bax), and METTL3 protein levels were examined by western blot assay. Cell viability and apoptosis were detected by Cell Counting Kit-8 (CCK-8) and TUNEL assays. Reactive oxygen species (ROS), malondialdehyde (MDA), and Glutathione peroxidase (GSH-Px) levels were examined using special assay kits. Interaction between METTL3 and PSAT1 was verified using methylated RNA immunoprecipitation (MeRIP) and dual-luciferase reporter assay.ResultsPSAT1 and METTL3 levels were decreased in DR patients and HG-treated ARPE-19 cells. Upregulation of PSAT1 might attenuate HG-induced cell viability inhibition and apoptosis and oxidative stress promotion in ARPE-19 cells. Moreover, PSAT1 was identified as a downstream target of METTL3-mediated m6A modification. METTL3 might improve the stability of PSAT1 mRNA via m6A methylation.ConclusionMETTL3 might mitigate HG-induced ARPE-19 cell damage partly by regulating the stability of PSAT1 mRNA, providing a promising therapeutic target for DR.

PFKP inhibition protects against pathological cardiac hypertrophy by regulating protein synthesis

Metabolic reprogramming precedes most alterations during pathological cardiac hypertrophy and heart failure (HF). Recent studies have revealed that Phosphofructokinase, platelet (PFKP) has a wealth of metabolic and non-metabolic functions. In this study, we explored the role of PFKP in cardiac hypertrophic growth and HF. The expression level of PFKP was elevated both in pathological cardiac remodeling mouse model challenged by transverse aortic constriction (TAC) surgery and in the neonatal rat cardiomyocytes (NRCMs) stimulated by phenylephrine (PE). In global PFKP knockout (PFKP-KO) mice, cardiac hypertrophy was ameliorated under TAC surgery, while overexpression of PFKP by intravenous injection of adeno-associated virus 9 (AAV9) under the cardiac troponin T (cTnT) promoter worsened myocardial hypertrophy and fibrosis. In NRCMs, small interfering RNA (SiRNA) knockdown or adenovirus (Adv) overexpression of PFKP was employed and the intervention of PFKP showed a similar phenotype. Mechanistically, immunoprecipitation combined with liquid chromatography-tandem mass spectrometry (IP-MS/MS) analysis was used to identify the interacting proteins of PFKP. Eukaryotic translation initiation factor 2 subunit beta (EIF2S2) was identified as the downstream target of PFKP. In the PE-stimulated NRCM hypertrophy model and mouse TAC model, knocking down EIF2S2 after PFKP overexpression reduced the synthesis of new proteins and alleviated the hypertrophy phenotype. Our findings illuminate that PFKP participates in pathological cardiac hypertrophy partly by regulating protein synthesis through EIF2S2, which provides a new clue for the involvement of metabolic intermediates in signal transduction.

The potential role of Circular RNA New biomarkers for the prognosis of hepatocellular carcinoma

Abstract Introduction/Objective Hepatocellular carcinoma (HCC) is the most commonly diagnosed cancer with related deaths worldwide. The non-coding RNAs as the functions of circRNAs in tumor progression have attracted great attention to the clinicopathological characteristics of HCC. Methods/Case Report The present study was conducted to investigate and evaluate the expression level of hsa_circ_2124, and hsa_circ_4018 downstream target gene pathways related to clinico-pathological parameters of HCC. Cell proliferation was examined by West-1 assay and protein expression levels by using western blotting analysis. Results (if a Case Study enter NA) The hsa_circ_2124 expression level was up-regulated in HepG2 and Hep3B cells, respectively compared to normal liver cells. Furthermore, hsa_circ_4018 was down-regulated in two HCC cell lines compared to the normal cell line (LO2 cells), demonstrating the heterogeneity characteristics of the circRNA expressions in different HCC cell lines. Our data showed a significant inhibition of hsa_circ_4018 in HCC cell lines which in turn inhibited cell proliferation and migration. Besides, there is an inhibition in cell proliferation after hsa_circ_2124 knockdown in the tested cell lines. In addition, our data reported that the Knockdown of hsa_circ_2124 reduced the expression of ERK, c-Myc, and β-catenin expression in Hep-G2 cells. Furthermore, hsa_circ_4018 showed significant inhibition in β-catenin and c-Myc expression levels in Hep3B cells compared to the control. The knockdown of hsa_circ_2124 induced G1-phase arrest in HepG2 cells compared to control, suggesting the role of hsa_circ_2124 in the inhibition of HCC progression. Conclusion All in all, our data revealed that hsa_circ_2124 or hsa_circ_4018 plays a role in the regulation of MAPK and Wnt/β-catenin signaling pathways, which might be potential therapeutic biomarkers for HCC.

NLRP3 deficiency improves bone healing of tooth extraction sockets through SMAD2/3-RUNX2 mediated osteoblast differentiation.

Impaired bone healing following tooth extraction poses a significant challenge for implantation. As a crucial component of the natural immune system, the NLRP3 inflammasome is one of the most extensively studied Pattern-Recognition Receptors (PRRs), and is involved in multiple diseases. Yet, the role of NLRP3 in bone healing remains to be clarified. Here, to investigate the effect of NLRP3 on bone healing, we established a maxillary first molar extraction model in wild-type (WT) and NLRP3KO mice using minimally invasive techniques. We observed that NLRP3 was activated during the bone repair phase, and its depletion enhanced socket bone formation and osteoblast differentiation. Moreover, NLRP3 inflammasome activation was found to inhibit osteogenic differentiation in alveolar bone-derived mesenchymal stem cells (aBMSCs), an effect mitigated by NLRP3 deficiency. Mechanistically, we established that SMAD2/3-RUNX2 signaling pathway is a downstream target of NLRP3 inflammasome activation, and SMAD2/3 knockdown partially reversed the significant decrease in expression of RUNX2, OSX, and ALP induced by NLRP3. Thus, our findings demonstrate that NLRP3 negatively modulates alveolar socket bone healing and contribute to the understanding of the NLRP3-induced signaling pathways involved in osteogenesis regulation.

Transforming growth factor-beta and Epithelial-mesenchymal transition is considered an attractive pivotal Genetic-Biomarker for Hepatocellular carcinoma with hepatitis C virus-infection patients

Abstract Introduction/Objective Hepatocellular carcinoma (HCC) is the most common cause of cancer worldwide. HCC is induced by hepatitis C-virus (HCV) which represents a major health problem in Egypt. The transforming growth factor- beta (TGF-β) is a potent cytokine that has a multifunctional pro-fibrotic activity, for enhancing liver-inflammation, fibrosis, tumor-progression, and metastasis. TGF-β has a vital role in the regulation of tumorigenesis, by controlling epithelial-mesenchymal-transition (EMT), apoptosis, proliferation, and differentiation process. The dysregulation of TGF-β, Wnt/β-catenin signaling pathways, by HCV-core protein is implicated in the development of HCC. Methods/Case Report The study aims to determine the effect of the HCV-infection in HCC patients with a set of growth-factors, EMT, and anti-apoptotic protein expression levels by using western blotting and immunohistochemistry staining analysis. Results (if a Case Study enter NA) These results observed an insignificant increase in the expression of TGF-β protein for HCC/HCV-infected cells compared to the HCV-uninfected cells, and the expression of the β-catenin protein level is elevated in the nucleus. Also, it showed that Bcl-2 protein is a significant increase in HCV-infected when compared to HCV-free groups. Positive staining for p53 protein was detected in the HCC/HCV-infected, more than in HCC/HCV-uninfected cells. This data indicated that the core-protein of HCV can switch TGF-β from a tumor suppressor to a tumor promoter by suppressing apoptosis of hepatocytes and increasing EMT expression by activation of Wnt/β-catenin signaling pathway. Therefore, HCV-core protein enhances the nuclear accumulation of β-catenin expression protein to activate downstream target genes, which regulate cell-growth and cell-cycle progression. Conclusion It is speculated that HCV may exert an anti-apoptotic effect, and thus enhance tumorigenesis. Also, the accumulation of nuclear Wnt/β-catenin and p53 correlates with TGF-β expression, typically a late event in hepato- carcinogenesis. Taken together, the expression level of TGF-β, Wnt/β-catenin, Bcl-2, and p53 genotype in HCV is considered an indicator of shortened survival in patients, and may be an attractive clinically pivotal genetic biomarker to mediate liver pathogenesis.

Epigenetic regulation by polycomb repressive complex 1 promotes cerebral cavernous malformations.

Cerebral cavernous malformations (CCMs) are anomalies of the cerebral vasculature. Loss of the CCM proteins CCM1/KRIT1, CCM2, or CCM3/PDCD10 trigger a MAPK-Krüppel-like factor 2 (KLF2) signaling cascade, which induces a pathophysiological pattern of gene expression. The downstream target genes that are activated by KLF2 are mostly unknown. Here we show that Chromobox Protein Homolog 7 (CBX7), component of the Polycomb Repressive Complex 1, contributes to pathophysiological KLF2 signaling during zebrafish cardiovascular development. CBX7/cbx7a mRNA is strongly upregulated in lesions of CCM patients, and in human, mouse, and zebrafish CCM-deficient endothelial cells. The silencing or pharmacological inhibition of CBX7/Cbx7a suppresses pathological CCM phenotypes in ccm2 zebrafish, CCM2-deficient HUVECs, and in a pre-clinical murine CCM3 disease model. Whole-transcriptome datasets from zebrafish cardiovascular tissues and human endothelial cells reveal a role of CBX7/Cbx7a in the activation of KLF2 target genes including TEK, ANGPT1, WNT9, and endoMT-associated genes. Our findings uncover an intricate interplay in the regulation of Klf2-dependent biomechanical signaling by CBX7 in CCM. This work also provides insights for therapeutic strategies in the pathogenesis of CCM.

ALKBH5 governs human endoderm fate by regulating the DKK1/4-mediated Wnt/β-catenin activation.

N6-methyladenonsine (m6A) is ubiquitously distributed in mammalian mRNA. However, the precise involvement of m6A in early development has yet to be fully elucidated. Here, we report that deletion of the m6A demethylase ALKBH5 in human embryonic stem cells (hESCs) severely impairs definitive endoderm (DE) differentiation. ALKBH5-/- hESCs fail to undergo the primitive streak (PS) intermediate transition that precedes endoderm specification. Mechanistically, we show that ALKBH5 deficiency induces m6A hypermethylation around the 3' untranslated region (3'UTR) of GATA6 transcripts and destabilizes GATA6 mRNA in a YTHDF2-dependent manner. Moreover, GATA6 binds to the promoters of critical regulatory genes involved in Wnt/β-catenin signaling transduction, including the canonical Wnt antagonist DKK1 and DKK4, which are unexpectedly repressed upon the dysregulation of GATA6 mRNA metabolism. Remarkably, DKK1 and DKK4 both exhibit a pleiotropic effect in modulating the Wnt/β-catenin cascade and guard the endogenous signaling activation underlying DE formation as potential downstream targets of the ALKBH5-GATA6 regulation. Here, we unravel a role of ALKBH5 in human endoderm formation in vitro by modulating the canonical Wnt signaling logic through the previously unrecognized functions of DKK1/4, thus capturing a more comprehensive role of m6A in early human embryogenesis.

Improvement of primary Sjögren's syndrome salivary gland function by Xinfeng capsule and its effect on EGR1-STAT3 signaling pathway.

The study was aimed to investigate the effects of Xinfeng capsule (XFC) on tissue morphology, and gland function of the salivary gland (SG) in a primary Sjögren's syndrome (pSS) mouse model. An animal model of pSS was established by inducing SG protein in C57BL/6 mice. SG tissues were collected for tissue sequencing and subsequent experiments to detect the expression of cholinergic receptor muscarinic 3(M3R), early growth response factor 1 (EGR1) and target genes in the SG before and after XFC intervention, with in vitro validation. Downstream targets of the EGR1 gene were predicted and analyzed using data analysis. EGR1 showed high expression and was selected for subsequent experiments. Administration of XFC significantly increased saliva production (P < 0.001) and reduced the extent of lymphatic infiltration observed in SG. Furthermore, the expression of EGR1 was increased in the model group with statistical significance in contrast with the control group but decreased after administration of XFC (P < 0.05). Data analysis predicted the downstream target of EGR1 as signal transducer and activator of transcription 3 (STAT3), which was validated in SG tissues of mice (P < .05). XFC demonstrated a significant improvement in the salivary secretion function of the SG in pSS mice. EGR1 can serve as a biomarker and therapeutic target for pSS.

Exosomal circPTPRK promotes angiogenesis after radiofrequency ablation in hepatocellular carcinoma.

Radiofrequency ablation (RFA) is an effective treatment for hepatocellular carcinoma (HCC), but the recurrence rate remains high due to angiogenesis in residual cancer cells. We used thermal stimulation to simulate the post-RFA microenvironment. The expression profile of circRNAs between normal control HCC cell-derived exosomes and exosomes after heat stimulation were analyzed by RNA sequencing. Quantitative real-time PCR was applied to evaluate the expression of circPTPRK in exosomes and human umbilical vein endothelial cells (HUVECs). Then, the functions of heat-stimulated HCC cell-derived exosomes and exosomal circPTPRK on HUVECs were unveiled. Transcriptome sequencing was utilized to determine targeted genes of circPTPRK. Heat-stimulated HCC cell-derived exosomes augmented cell proliferation, migration, and angiogenesis of HUVECs. In total, 229 differentially expressed circRNAs were obtained, including 211 upregulated circRNAs and 18 downregulated circRNAs in heat-stimulated HCC cell-derived exosomes. The expression of circPTPRK was remarkably increased in heat-stimulated HCC cell-derived exosomes and the HUVECs incubated with them. Heat-stimulated HCC cell-derived exosomes with circPTPRK knockdown significantly inhibited cell proliferation, migration, and angiogenesis of HUVECs. Mechanistic studies indicated that PLA2G4E is a downstream target of circPTPRK, and PLA2G4E overexpression reversed the inhibitory effect of circPTPRK knockdown on HUVEC angiogenesis. Our results indicated that exosomal circPTPRK activated HUVEC angiogenesis by upregulating PLA2G4E expression.

RBM15 drives the progression of lung adenocarcinoma by regulating N6-methyladenosine-mediated LDHA mRNA stability

Abnormal N6-methyladenosine (m6A) methylation in RNA plays a pivotal role in the pathogenesis of many types of tumors by influencing mRNA metabolism, alternative splicing, translocation, stability and translation. However, the specific regulators and underlying mechanisms of m6A modification in the progression of lung adenocarcinoma are not well understood. In this study, we analyzed the RNA-seq transcriptome data downloaded from The Cancer Genome Atlas (TCGA) database, and identified “m6A writer” RNA binding motif protein 15 (RBM15) expression was significantly elevated in lung adenocarcinoma (LUAD) biopsies, and the higher RBM15 levels were correlated with the poorer overall survival (OS) of LUAD patients. Further study confirmed RBM15 was prominently expressed in LUAD tissues and cell lines. Moreover, silencing RBM15 in PC9 and H1299 cells reduced cell proliferation both in vitro and in vivo, while overexpression of RBM15 in A549 cells promoted cell growth. Mechanistically, lactate dehydrogenase A (LDHA) acted as a downstream target of RBM15. RBM15-mediated m6A modification of LDHA mRNA enhanced its stability to exert an oncogenic role in LUAD. Taken together, our findings suggest that the RBM15/LDHA axis might be a novel and promising therapeutic target for LUAD.