Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease characterized by excessive ECM deposition and myofibroblast accumulation driven by cytokine dysregulation. This study identified granulocyte colony-stimulating factor 3 (CSF3) as a key mediator of IPF progression. Elevated CSF3 expression was observed in the lung tissues of IPF patients. Recombinant CSF3 promoted myofibrogenesis in lung fibroblasts, whereas CSF3-deficient mice were protected from bleomycin-induced pulmonary fibrosis. Treatment with novel CSF3-neutralizing antibodies significantly restored fibrosis in IPF mice by suppressing myofibroblast differentiation and reducing ECM deposition. Here, we demonstrated a reciprocal regulatory relationship between CSF3 and TGF-β that amplifies pro-fibrotic signaling. Our mechanistic studies revealed that CSF3 acts as an upstream regulator of TGF-β, forming a positive feedback loop that significantly accelerates the fibrotic process. Knockout or neutralization of CSF3 suppressed fibrosis by reducing TGF-β levels, whereas treatment with recombinant CSF3 promoted fibrosis with increased TGF-β expression. Notably, while CSF3 inhibition reduced TGF-β expression levels, it did not decrease them below normal levels. This finding suggests that inhibiting CSF3 could simultaneously reduce fibrosis by suppressing excessive TGF-β expression while also minimizing side effects by maintaining TGF-β homeostasis. Taken together, these results provide strong evidence that CSF3 is a critical driver of IPF pathogenesis and that targeting CSF3 may provide a therapeutic strategy by modulating TGF-β signaling and restoring the ECM and cellular homeostasis.
The urothelium is stratified into progenitor basal cells, intermediate cells, and terminally differentiated umbrella cells. Proper renewal of umbrella cells is necessary for maintaining urinary tract barrier integrity. To investigate whether mRNA alternative cleavage and polyadenylation (APA) regulates urothelial differentiation, we developed a single-cell polyadenylation site usage (scPASU) computational pipeline to map cell state-specific polyadenylation sites in single-cell RNA-seq data from 13,544 urothelial cells. Leveraging single-cell spatial imaging, we directly visualized APA events in situ, revealing their spatial specificity within the adult human ureter. APA shaped urothelial differentiation, independent of gene expression changes. Furthermore, key APA-regulated genes shared conserved motifs in their 3' UTRs, often containing Alu elements, suggesting a potential mechanism regulating poly(A) site selection. Our study establishes APA as a driver of urothelial transcriptome diversity. ### Competing Interest Statement The authors have declared no competing interest.
Anticancer drug resistance remains a significant challenge to the efficacy of cancer treatment, with DNA repair enzymes contributing to this resistance. We hypothesized that thymine DNA glycosylases (TDGs) may be involved in anticancer drug resistance given their dual function of DNA repair and demethylation as well as investigated their possible involvement in the induction of β-catenin in SNUC5 cells resistant to 5-fluorouracil (SNUC5/5-FUR) and oxaliplatin (SNUC5/OXTR). The expression of TDG and phospho-β-catenin increased in both resistant cell types when compared to that in SNUC5 cells. Moreover, knockdown of TDG significantly suppressed phospho-β-catenin expression in both resistant cell types, resulting in enhanced sensitivity to anticancer drugs. TDG binding to the β-catenin promoter was stronger in both resistant cell types than in SNUC5 cells, showing a decreased methylation pattern in the CpG islands of the β-catenin promoter. Furthermore, another DNA demethylase, ten-eleven translocation 1 (TET1), showed the same pattern as TDG in both resistant cell types. Additionally, TDG significantly interacted more with TET1 in both resistant cell types than in SNUC5 cells, enhancing binding to the same locus in the β-catenin promoter. These findings suggest that TDG may be a promising target molecule for overcoming drug resistance in colorectal cancer.
BACKGROUND:Cereblon (CRBN) serves as the substrate recognition subunit of the CRL4-CRBN E3 ubiquitin ligase complex and isthe primary target of immunomodulatory drugs (IMiDs) in cancer therapy. While CRBN mutations occur infrequently in cancer, reduced CRBN expression correlates with poor IMiD response and treatment resistance, suggesting nongeneticregulatory mechanisms may govern CRBN expression. OBJECTIVE:We investigated CRBN expression patterns across multiple cancer types and examined the role of promotermethylation in regulating CRBN expression and its clinical significance. METHODS:We analyzed CRBN expression patterns using GENT2 database analysis and examined CRBN methylation status indiverse human cancer cell lines using methylation-specific PCR (MSP) and bisulfite genomic sequencing. We analyzedthe clinical significance of CRBN methylation and expression using TCGA and GENT2 databases with Kaplan-Meiersurvival analyses. RESULTS:CRBN expression was significantly downregulated in breast, cervical, head and neck, lung, and skin cancers comparedto normal tissues. We identified a CpG island 1kb upstream of the CRBN transcriptional start site, with cancer celllines exhibiting partial methylation patterns. Bisulfite sequencing confirmed specific CpG methylation sites withinCRBN promoter regions. CRBN promoter hypermethylation significantly correlated with increased mortality risk inbreast, lung, acute myeloid leukemia, and bladder cancers, while low CRBN expression was associated with poorsurvival in breast, lung, brain, and ovarian cancers. Combined low expression and high methylation stronglypredicted poor outcomes in breast and lung cancers. CONCLUSIONS:CRBN expression is partially regulated by promoter methylation in specific cancer types, with epigenetic silencingcontributing to treatment resistance and poor prognosis. CRBN methylation and expression serve as important pancancerprognostic biomarkers, highlighting the potential for epigenetic therapies to restore CRBN function andovercome therapeutic resistance.
Specific sensitivity of the skin to ultraviolet B (UVB) rays is one of the mechanisms responsible for widespread skin damage. This study tested whether 1,3,5-trihydroxybenzene (THB), a compound abundant in marine products, might inhibit UVB radiation-induced NADPH oxidase 4 (NOX4) in both human HaCaT keratinocytes and mouse dorsal skin and explore its cytoprotective mechanism. The mechanism of action was determined using western blotting, immunocytochemistry, NADP+/NADPH assay, reactive oxygen species (ROS) detection, and cell viability assay. THB attenuated UVB-induced NOX4 expression both in vitro and in vivo, and suppressed UVB-induced ROS generation via NADP+ production, resulting in increased cell viability with decreased apoptosis. THB also reduced the expression of UVB-induced phosphorylated AMP-activated protein kinase (AMPK) and phosphorylated c-Jun N-terminal kinase (JNK). THB suppressed UVB-induced NOX4 expression and ROS generation by inhibiting AMPK and JNK signaling pathways, thereby inhibiting cellular damage. These results showed that THB could be developed as a UV protectant.
BRAF activating mutations occur in approximately 10% of metastatic colorectal cancer (CRCs) and are associated with worse prognosis due to an inferior response to standard chemotherapy. Standard of care for patients with refractory metastatic BRAF V600E CRC is treatment with BRAF and EGFR inhibitors. However, responses are not durable. Lineage plasticity to neuroendocrine cancer is an emerging mechanism of targeted therapy resistance in several cancer types. Enteroendocrine cells (EECs), the neuroendocrine cell of the intestine, are uniquely present in BRAF V600E CRC as compared to BRAF wildtype CRC. Here, we demonstrated that combined BRAF and EGFR inhibition enriches for EECs in several models of BRAF V600E CRC. Additionally, EECs and other secretory cell types were enriched in a subset of BRAF V600E CRC patient samples following targeted therapy. Importantly, inhibition of the lysine demethylase LSD1 with a clinically relevant inhibitor attenuated targeted therapy-induced EEC enrichment through blocking the interaction of LSD1, CoREST2 and STAT3. Statement of Significance:Our findings that BRAF plus EGFR inhibition induces lineage plasticity in BRAF V600E CRC represents a new paradigm for how resistance to BRAF plus EGFR inhibition occurs and our finding that LSD1 inhibition blocks lineage plasticity has the potential to improve responses to BRAF plus EGFR inhibitor therapy in patients.
Background Environmental exposure, medical diagnostic and therapeutic applications, and industrial utilization of radionuclides have prompted a growing focus on the risks associated with low-dose radiation (< 100 mGy). Current evidence suggests that such radiation can induce epigenetic changes. Nevertheless, whether exposure to low-dose radiation can disrupt endothelial cell function at the molecular level is unclear. Because endothelial cells play crucial roles in cardiovascular health and disease, we aimed to investigate whether low-dose radiation could lead to differential DNA methylation patterns at the genomic level in endothelial cell (EC) lines. Methods We screened for changes in DNA methylation patterns in primary human aortic (HAECs) and coronary artery endothelial cells following exposure to low-dose ionizing radiation. Using a subset of genes altered via DNA methylation by low-dose irradiation, we performed gene ontology (GO) analysis to predict the possible biological network mediating the effect of low-dose radiation. In addition, we performed comprehensive validation using methylation and gene expression analyses, and ChIP assay to identify useful biomarkers among candidate genes for use in detecting low-dose radiation exposure in human primary normal ECs. Results Low-dose radiation is sufficient to induce global DNA methylation alterations in normal EC lines. GO analysis demonstrated that these hyper- or hypo-methylated genes were linked to diverse biological pathways. Our findings indicated a robust correlation between promoter hypermethylation and transcriptional downregulation of four genes ( PGRMC1 , UNC119B , RERE , and FNDC3B ) in response to low-dose ionizing radiation in HAECs. Conclusions Based on these findings, the identified genes can serve as potential DNA methylation biomarkers for the assessment of cardiovascular risk upon exposure to low-dose radiation.
High-dose radiation (HDR) is widely used for cancer treatment, but the effectiveness of low-dose radiation (LDR) in the treatment of various diseases is controversial. Therefore, to safely utilize LDR for therapeutic purposes, further research on its numerous biological effects of LDR is required. Interest in the increased use of medical imaging devices or the effects of surrounding living environmental radiation on the human body, particularly on fibrosis, is rapidly increasing. Therefore, this study aimed to verify the relationship between LDR and pulmonary fibrosis by evaluating the changes in fibroblasts after LDR treatment and their associated signaling mechanisms. LDR increased the expression of fibrosis markers COL1A1 and α-SMA, cell proliferation, and migration by activating YAP1 and Twist in fibroblasts. Meanwhile, miRNA was employed as a tool to inhibit LDR-induced fibrosis and it was found that miR-765 simultaneously targeted COL1A1, α-SMA, and YAP1. At the cellular level, miR-765 reduced the proliferation and migration of fibroblasts by suppressing the expression of LDR-induced fibrosis factors COL1A1, α-SMA, and YAP1. The efficacy of miR-765 in vivo was confirmed using bleomycin (BLM)-induced fibrotic mouse model. The characteristics of pulmonary fibrosis were reduced after injection of miR-765-overexpressing cells into BLM-induced fibrotic mice. In addition, the suppression of miR-765 expression in the plasma of patients with pulmonary fibrosis confirmed the negative relationship between pulmonary fibrosis and miR-765 expression. Therefore, this study demonstrates that miR-765 is a potential novel diagnostic biomarker and major target for the development of therapeutic agents to inhibit pulmonary fibrosis.
BACKGROUND:Human endogenous retroviruses (HERVs), integrated into the human genome during primate evolution, constitute approximately 8% of the human genome. Although most HERVs are non-protein-coding owing to mutations, insertions, deletions, and truncations, recent research has revealed their diverse roles in biological processes, including disease pathogenesis. OBJECTIVE:Although many HERVs remain inactive, they have been implicated in various diseases, particularly cancer, prompting an increased interest in harnessing HERVs for therapeutic purposes. This review explores the recent advancements in our understanding of the biological roles of HERVs, emphasizing their clinical relevance in cancer treatment. METHODS:Here, we discuss how the detection of transposable elements (TEs), including HERVs, by the immune system triggers innate immune responses in human cancers. CONCLUSION:Additionally, we outline recent progress in elucidating the implications of HERV activation in cancer and how targeting HERVs holds promise for anti-cancer treatments by modulating epigenetic plasticity and disrupting cancer initiation and progression.
Triple-negative breast cancer (TNBC), the most aggressive subtype, presents a critical challenge due to the absence of approved targeted therapies. Hence, there is an urgent need to identify effective therapeutic targets for this condition. While epidermal growth factor receptor (EGFR) is prominently expressed in TNBC and recognized as a therapeutic target, anti-EGFR therapies have yet to gain approval for breast cancer treatment due to their associated side effects and limited efficacy. Here, we discovered that intercellular adhesion molecule-1 (ICAM-1) exhibits elevated expression levels in metastatic breast cancer and serves as a pivotal binding adaptor for EGFR activation, playing a crucial role in malignant progression. The activation of EGFR by tumor-expressed ICAM-1 initiates biased signaling within the JAK1/STAT3 pathway, consequently driving epithelial-to-mesenchymal transition and facilitating heightened metastasis without influencing tumor growth. Remarkably, ICAM-1-neutralizing antibody treatment significantly suppressed cancer metastasis in a breast cancer orthotopic xenograft mouse model. In conclusion, our identification of ICAM-1 as a novel tumor intrinsic regulator of EGFR activation offers valuable insights for the development of TNBC-specific anti-EGFR therapies.
Stimulation of human keratinocytes with particulate matter 2.5 (PM2.5) elicits complex signaling events, including a rise in the generation of reactive oxygen species (ROS). However, the mechanisms underlying PM2.5-induced ROS production remain unknown. Here, we show that PM2.5-induced ROS production in human keratinocytes is mediated via the NADPH oxidase (NOXs) system and the Ca2+ signaling pathway. PM2.5 treatment increased the expression of NOX1, NOX4, and a calcium-sensitive NOX, dual oxidase 1 (DUOX1), in human epidermal keratinocyte cell line. PM2.5 bound to aryl hydrocarbon receptor (AhR), and this complex bound to promoter regions of NOX1 and DUOX1, suggesting that AhR acted as a transcription factor of NOX1 and DUOX1. PM2.5 increased the transcription of DUOX1 via epigenetic modification. Moreover, a link between DNA demethylase and histone methyltransferase with the promoter regions of DUOX1 led to an elevation in the expression of DUOX1 mRNA. Interestingly, PM2.5 increased NOX4 expression and promoted the interaction of NOX4 and Ca2+ channels within the cytoplasmic membrane or endoplasmic reticulum, leading to Ca2+ release. The increase in intracellular Ca2+ concentration activated DUOX1, responsible for ROS production. Our findings provide evidence for a PM2.5-mediated ROS-generating system network, in which increased NOX1, NOX4, and DUOX1 expression serves as a ROS signal through AhR and Ca2+ activation.
Skin is a direct target of fine particulate matter (PM2.5), as it is constantly exposed. Herein, we investigate whether Korean red ginseng (KRG) can inhibit PM2.5-induced senescence in skin keratinocytes. PM2.5-treated human keratinocyte cell lines and normal human epidermal keratinocytes showed characteristics of cellular senescence, including flat and enlarged forms; however, KRG suppressed them in both cell types. Moreover, while cells exposed to PM2.5 showed a higher level of p16INK4A expression (a senescence inducer), KRG inhibited its expression. Epigenetically, KRG decreased the expression of the ten-eleven translocation (TET) enzyme, a DNA demethylase induced by PM2.5, and increased the expression of DNA methyltransferases suppressed by PM2.5, resulting in the decreased methylation of the p16INK4A promoter region. Additionally, KRG decreased the expression of mixed-lineage leukemia 1 (MLL1), a histone methyltransferase, and histone acetyltransferase 1 (HAT1) induced by PM2.5. Contrastingly, KRG increased the expression of the enhancer of zeste homolog 2, a histone methyltransferase, and histone deacetyltransferase 1 reduced by PM2.5. Furthermore, KRG decreased TET1, MLL1, and HAT1 binding to the p16INK4A promoter, corresponding with the decreased mRNA expression of p16INK4A. These results suggest that KRG exerts protection against the PM2.5-induced senescence of skin keratinocytes via the epigenetic regulation of p16INK4A.
- PDF file 64K, Supplementary Table S1. Primers used for MSP, RT-PCR, Bisulfite sequencing analyses
Supplementary Table 1 from Methylation of TFPI2 in Stool DNA: A Potential Novel Biomarker for the Detection of Colorectal Cancer
Although most human endogenous retroviruses (HERVs) have been silenced and lost their ability to translocate because of accumulated mutations during evolution, they still play important roles in human biology. Several studies have demonstrated that HERVs play pathological roles in numerous human diseases, especially cancer. A few studies have revealed that long non-coding RNAs that are transcribed from HERV sequences affect cancer progression. However, there is no study on microRNAs derived from HERVs related to cancer. In this study, we identified 29 microRNAs (miRNAs) derived from HERV sequences in the human genome. In particular, we discovered that miR-4454, which is HERV-H-derived miRNA, was upregulated in non-muscle-invasive bladder cancer (NMIBC) cells. To figure out the effects of upregulated miR-4454 in NMIBC, genes whose expression was downregulated in NMIBC, as well as tumor suppressor genes, were selected as putative target genes of miR-4454. The dual-luciferase assay was used to determine the negative relationship between miR-4454 and its target genes, DNAJB4 and SASH1, and they were confirmed to be promising target genes of miR-4454. Taken together, this study suggests that the upregulation of miR-4454 derived from HERV-H in NMIBC reduces the expression of the tumor suppressor genes, DNAJB4 and SASH1, to promote NMIBC progression.
Dipeptidyl peptidase-4 (DPP-4) inhibitors are glucose-lowering drugs for type 2 diabetes mellitus (T2DM). We investigated whether evogliptin® (EVO), a DPP-4 inhibitor, could protect against diabetic cardiomyopathy (DCM) and the underlying mechanisms. Eight-week-old diabetic and obese db/db mice were administered EVO (100 mg/kg/day) daily by oral gavage for 12 weeks. db/db control mice and C57BLKS/J as wild-type (WT) mice received equal amounts of the vehicle. In addition to the hypoglycemic effect, we examined the improvement in cardiac contraction/relaxation ability, cardiac fibrosis, and myocardial hypertrophy by EVO treatment. To identify the mechanisms underlying the improvement in diabetic cardiomyopathy by EVO treatment, its effect on lipotoxicity and the mitochondrial damage caused by lipid droplet accumulation in the myocardium were analyzed. EVO lowered the blood glucose and HbA1c levels and improved insulin sensitivity but did not affect the body weight or blood lipid profile. Cardiac systolic/diastolic function, hypertrophy, and fibrosis were improved in the EVO-treated group. EVO prevented cardiac lipotoxicity by reducing the accumulation of lipid droplets in the myocardium through suppression of CD36, ACSL1, FABP3, PPARgamma, and DGAT1 and enhancement of the phosphorylation of FOXO1, indicating its inhibition. The EVO-mediated improvement in mitochondrial function and reduction in damage were achieved through activation of PGC1a/NRF1/TFAM, which activates mitochondrial biogenesis. RNA-seq results for the whole heart confirmed that EVO treatment mainly affected the differentially expressed genes (DEGs) related to lipid metabolism. Collectively, these findings demonstrate that EVO improves cardiac function by reducing lipotoxicity and mitochondrial injury and provides a potential therapeutic option for DCM.
Supplementary Figure S2. Validation of up-regulation of gene expression after demethylation with DAC by qRT-PCR for 22 genes. Relative mRNA expression of 22 genes analyzed by qRT-PCR in ccRCC cell lines SKRC1, SKRC52 and SKRC59 treated with either mock or 5μm 5-aza-2'-deoxycytidine (DAC) for 96 hours. Expression levels were analyzed in triplo unless stated otherwise. Error bars indicate the standard error of the mean. * in duplo; ** single values due to technical failure; *** no expression in SKRC1 and SKRC59.
- PDF file 86K, Supplementary Table S2. BNC1 and ADAMTS1 Gene expression changes in pancreatic cancers from previously published microarray dataset