Krϋppel-like factors (KLFs) in renal physiology and disease

Construction and validation of a multi-mRNA panel and genetic scores for Krüppel-like factors for acute ischemic stroke

Cellular and animal experiments suggest that Krϋppel-like factors (KLFs) may be involved in the pathological mechanisms of acute ischemic stroke (AIS), but epidemiological research on KLFs in AIS is still limited. Therefore, we conducted two AIS case-control studies, and three prospective cohort studies to elucidate the contribution of 14 KLFs' distinct leukocytes mRNA expression (360 AIS cases vs. 363 controls) and 21 genetic tagSNPs (3651 AIS cases vs. 3900 controls) to the etiology and prognosis of AIS. We found KLFs mRNA score constructed by differentially expressed mRNAs significantly enhances the discriminative value for AIS compared to the traditional risk factors [the area under the curve (AUC) increased from 0.724 to 0.871]. Additionally, the KLFs polygenetic risk score could effectively stratify the susceptibility to AIS incidence (Ptrend < 0.001) and the highest PRS group has an increased 42.4 % risk of AIS onset in the cohort study. Furthermore, KLF12 mRNA negatively related to modified Rankin Scale (mRS) both at admission and discharge and KLF12 variants contributed to an elevated risk of IS death after AIS. In conclusion, this study provides new insights into the novel contribution of KLFs mRNA and genetic variants to the incidence risk and prognosis of AIS.

FBXW7 mediates high glucose-induced epithelial to mesenchymal transition via KLF5 in renal tubular cells of diabetic kidney disease

F-box and WD repeat domain-containing 7 (FBXW7) protein is known as one of the crucial components of the E3 ubiquitin ligase called the Skp1-Cullin1-F-box (SCF) complex, which regulates the degradation of a network of proteins via the ubiquitin-proteasome system. In our study, we investigated the latent impact of FBXW7 on renal tubular cells injury and its molecular mechanism in diabetic kidney disease (DKD). FBXW7 was upregulated in kidneys of diabetic mice and human renal proximal tubular cells exposed to high glucose. Again, the function of experiment found that overexpression of FBXW7 led to epithelial-mesenchymal transition (EMT) of HK2 cells, as indicated by decreased E-cadherin and increased α-smooth muscle actin (α-SMA). Knockdown of FBXW7 ameliorated high glucose-induced EMT of HK2 cells via downregulation of TGF-β1. Then, FBXW7 overexpression downregulated the stability of the KLF5 protein and promoted protein ubiquitination in normal glucose-cultured HK2 cells, which was significantly reversed by the addition of MG132, a specific proteasome inhibitor. Furthermore, overexpression of KLF5 effectively prevented FBXW7 upregulation-induced EMT in HK2 cells. Finally, chemical inhibitors or mTOR kinase dead vector to interfere the activity of mTOR effectively suppressed FBXW7 expression in HK2 cells treated with high glucose. Taken together, these above data suggest that mTOR signaling pathway-regulated FBXW7 mediates high glucose-induced EMT of renal tubular cells by affecting the stability of KLF5.

KLF10 Induced by Hypothermic Machine Perfusion Alleviates Renal Inflammation Through BIRC2 /Noncanonical NF-κB Pathway

BACKGROUND

Hypothermic machine perfusion (HMP) is becoming the main preservation method for donation after circulatory death (DCD) kidneys. It can provide continuous flow and form shear stress (SS) upon endothelial cells (ECs), thereby regulating EC injury. Krüppel-like factor 10 (KLF10) has been shown to lessen vascular damage. However, how SS and KLF10 impact HMP-regulated injury is unclear.

METHODS

In this study, we investigated the influences of KLF10 on HMP in animal models and human renal biopsy and explored how SS affected KLF10 expression in a parallel-plate flow chamber system. Chromatin Immunoprecipitation sequencing and luciferase assay were performed to seek the target genes of KLF10. The influences of KLF10 on HMP-regulated injury were investigated by transfecting si-KLF10 adeno-associated virus serotype 9 into rat kidneys. The molecular expression was examined using immunofluorescence staining, Western blotting, and quantitative polymerase chain reaction.

RESULTS

Our results show KLF10 expression was augmented in human, rabbit, and rat DCD kidneys after HMP. HMP improved ECs and tubule injury and attenuated inflammation; however, the knockdown of KLF10 reversed this effect. SS regulated KLF10 expression in ECs by affecting F-actin, and KLF10 could maintain ECs homeostasis. Chromatin Immunoprecipitation sequencing and luciferase assay revealed that baculoviral inhibitor of apoptosis protein repeat-containing 2 (BIRC2) is a target gene of KLF10. Furthermore, BIRC2 linked to nuclear factor kappa B (NF-κB)-inducing kinase, induced NF-κB)-inducing kinase ubiquitination, and resulted in inhibiting the noncanonical NF-κB pathway.

CONCLUSIONS

SS can mediate KLF10 expression, whereas HMP can protect against warm ischemic injury by reducing inflammation via KLF10/BIRC2/noncanonical NF-κB pathway. Therefore, KLF10 might be a novel target for improving DCD kidney quality.

EPB41L3 Inhibits the Progression of Cervical Cancer Via the ERK/p38 MAPK Signaling Pathway

This study was aimed to uncover the character and potential regulatory mechanism of EPB41L3 in cervical cancer (CC). CC cells were injected into BALB/c nude mice (female) to construct a xenograft tumor model. Real-time quantitative polymerase chain reaction (qRT-PCR) and western blot were performed to evaluate the expression of EPB41L3, ERK/p38 MAPK signal markers in CC tissues and cells. Cell counting kit-8 (CCK-8) and Transwell was applied to analyze the viability, invasion, and migration of CC cell lines. EPB41L3 was substantially decreased both in CC tissues and cells. Cell viability, invasion, and migration of CC cells were reduced by overexpressing EPB41L3. Bioinformatics analysis prerdicted that EPB41L3 was strongly related to the ERK/p38 MAPK pathway. Compared with Ad-nc mice, the volume and weight of tumors and ERK/p38 MAPK signal markers were down-regulated in Ad-EPB41L3 mice. After knocking down EPB41L3 with EPB41L3 siRNA (siEPB41L3), the ERK/p38 MAPK pathway was activated. Moreover, SB203580 treatment reversed the effect of EPB41L3 silencing on the improvement in viability, migration, and invasion of CC cells. EPB41L3 suppresses the progression of CC via activating the ERK/p38 MAPK pathway. EPB41L3 may serve as an effective therapeutic target for CC.

Apelin/APJ alleviates diabetic nephropathy by improving glomerular endothelial cells dysfunction via SIRT3‑KLF15

Glomerular basement membrane (GBM) thickening, the earliest morphological change of diabetic nephropathy (DN), is related to glomerular endothelial cells (GECs) dysfunction which increase extracellular matrix (ECM) synthesizing. Apelin, the endogenous ligand for apelin/apelin receptor (APJ), is reported to alleviate endothelial cell dysfunction in DN. Therefore, it was hypothesized that apelin/APJ reduced GBM thickening by decreasing the synthesis of ECM in GECs. The results showed that apelin reduced glomerular fibrosis and GBM thickening by decreasing the expression of laminin and collagen IV in diabetic mice, which were cancelled following APJ knockout in GECs. Furthermore, apelin/APJ inhibited the synthesis of laminin and collagen IV in GECs by increasing the expression and activity of SIRT3, which promoted KLF15 deacetylation and translocation into nucleus. In conclusion, apelin/APJ reduced GBM thickening in diabetes mellitus by preventing laminin and collagen IV synthesizing via SIRT3‑KLF15 pathway in GECs.

The integrin repertoire drives YAP-dependent epithelial:stromal interactions during injury of the kidney glomerulus

The kidney glomerulus is a filtration barrier in which capillary loop architecture depends on epithelial-stromal interactions between podocytes and mesangial cells. Podocytes are terminally differentiated cells within the glomerulus that express YAP and TAZ. Here we test the hypotheses that YAP and TAZ are required in podocytes to maintain capillary loop architecture and that shifts in the integrin repertoire during podocyte injury affect transcriptional activity of YAP and TAZ. Loss of YAP in podocytes of adult mice renders them more sensitive to injury, whereas loss of both YAP and TAZ in podocytes rapidly compromises the filtration barrier. α3β1 and αvβ5 are two prominent integrins on murine podocytes. Podocyte injury or loss of α3β1 leads to increased abundance of αvβ5 and nuclear localization of YAP. In vitro, blockade of αvβ5 decreases nuclear YAP. Increased αv integrins are found in human kidney disease. Thus, our studies demonstrate the crucial regulatory interplay between cell adhesion and transcriptional regulation as an important determinant of human disease.

Inflammation in glomerular diseases

The structural and functional integrity of glomerular cells is critical for maintaining normal kidney function. Glomerular diseases, which involve chronic histological damage to the kidney, are related to injury to glomerular cells such as endothelial cells, mesangial cells (MCs), and podocytes. When faced with pathogenic conditions, these cells release pro-inflammatory cytokines such as chemokines, inflammatory factors, and adhesion factors. These substances interact with glomerular cells through specific inflammatory pathways, resulting in damage to the structure and function of the glomeruli, ultimately causing glomerular disease. Although the role of inflammation in chronic kidney diseases is well known, the specific molecular pathways that result in glomerular diseases remain largely unclear. For a long time, it has been believed that only immune cells can secrete inflammatory factors. Therefore, targeted therapies against immune cells were considered the first choice for treating inflammation in glomerular disease. However, emerging research indicates that non-immune cells such as glomerular endothelial cells, MCs, and podocytes can also play a role in renal inflammation by releasing inflammatory factors. Similarly, targeted therapies against glomerular cells should be considered. This review aims to uncover glomerular diseases related to inflammation and pathways in glomerular inflammation, and for the first time summarized that non-immune cells in the glomerulus can participate in glomerular inflammatory damage by secreting inflammatory factors, providing valuable references for future strategies to prevent and treat glomerular diseases. More importantly, we emphasized targeted glomerular cell therapy, which may be a key direction for the future treatment of glomerular diseases.

High Glucose Treatment Induces Nuclei Aggregation of Microvascular Endothelial Cells via the foxo1a-klf2a Pathway

BACKGROUND

Hyperglycemia is a major contributor to endothelial dysfunction and blood vessel damage, leading to severe diabetic microvascular complications. Despite the growing body of research on the underlying mechanisms of endothelial cell (EC) dysfunction, the available drugs based on current knowledge fall short of effectively alleviating these complications. Therefore, our endeavor to explore novel insights into the cellular and molecular mechanisms of endothelial dysfunction is crucial for the field.

METHODS

In this study, we performed a high-resolution imaging and time-lapse imaging analysis of the behavior of ECs in Tg(kdrl:ras-mCherry::fli1a:nGFP) zebrafish embryos upon high glucose treatment. Genetic manipulation and chemical biology approaches were utilized to analyze the underlying mechanism of high glucose-induced nuclei aggregation and aberrant migration of zebrafish ECs and cultured human ECs. Bioinformatical analysis of single-cell RNA-sequencing data and molecular biological techniques was performed to identify the target genes of foxo1a.

RESULTS

In this study, we observed that the high glucose treatment resulted in nuclei aggregation of ECs in zebrafish intersegmental vessels. Additionally, the aberrant migration of microvascular ECs in high glucose-treated embryos, which might be a cause of nuclei aggregation, was discovered. High glucose induced aggregation of vascular endothelial nuclei via foxo1a downregulation in zebrafish embryos. Then, we revealed that high glucose resulted in the downregulation of foxo1a expression and increased the expression of its direct downstream effector, klf2a, through which the aberrant migration and aggregation of vascular endothelial nuclei were caused.

CONCLUSIONS

High glucose treatment caused the nuclei of ECs to aggregate in vivo, which resembles the crowded nuclei of ECs in microaneurysms. High glucose suppresses foxo1a expression and increases the expression of its downstream effector, klf2a, thereby causing the aberrant migration and aggregation of vascular endothelial nuclei. Our findings provide a novel insight into the mechanism of microvascular complications in hyperglycemia.

Finerenone Ameliorates High Glucose-Induced Podocytes Epithelial-Mesenchymal Transition Through the Regulation of Krüppel-Like Factor 5 in Diabetic Nephropathy

Introduction

Diabetic nephropathy (DN) could impair the function of the glomerular filtration barrier by damaging the podocytes. Extant research has demonstrated that aldosterone plays a crucial role in this progression. Finerenone is a novel, high-selective mineralocorticoid receptor antagonist that has been demonstrated to be efficacious in renal protection in DN patients, albeit with an unclear underlying mechanism.

Methods

Podocytes were stimulated with RPMI 1640 medium containing different concentrations of glucose and treated with finerenone to evaluate the protective effect of finerenone on podocytes in high glucose environment. Intraperitoneal injection of STZ was used to induce diabetic nephropathy rats and intragastric administration with finerenone or vehicles, and the changes of renal function, renal pathological changes and renal tissue protein expression were assayed.

Results

Cell experiment showed that high glucose could induce epithelial-mesenchymal transition (EMT). After finerenone treatment, we accessed the EMT-related protein and found EMT was reversed. Besides, the cell migration capacity and cytoskeleton were also ameliorated. To further explore the mechanism, we found that finerenone could upregulate the expression of Krüppel-like factor 5 (KLF5) which was downregulated in a high glucose environment. After the silence of KLF5 in the presence of finerenone, the rescue experiment showed the protective function of finerenone is counteracted by KLF5. In animal experiment, after the treatment of finerenone, the level of blood creatinine decreased compared with the DN group while blood urea nitrogen (BUN) and potassium showed no significant difference. The pathological alterations of the treatment group also got ameliorated. Finerenone could normalize the level of EMT-related protein, nephrin, and KLF5 of kidney tissue in DN rats.

Conclusion

Our results suggest that finerenone could alleviate high glucose-induced podocyte EMT via regulating KLF5. Further investigation is warranted to elucidate the precise underlying mechanism.

The miR-1305/KLF5 negative regulatory loop affects pancreatic cancer cell proliferation and apoptosis

Pancreatic cancer (PC) is characterized by a high relapse rate and unfavorable prognosis. Currently, the optimal treatment for PC is complete resection followed by adjuvant systemic chemotherapy. Nevertheless, tumor cell repopulation and subsequent tumor relapse and metastasis after chemotherapy result in a poor prognosis. Therefore, it is of great value to explore the potential molecular mechanisms underlying PC for developing novel treatment strategies. Herein, we aimed to investigate the potential regulatory mechanism of miR-1305 upon aerobic proliferation, metastasis, and apoptosis in PC. miR-1305 was downregulated in PC tissues and cell lines. miR-1305 overexpression prominently inhibited PC cell proliferation and metastasis promoted cell apoptosis in vitro, and alleviated PC formation in vivo. As predicted, KLF5 could directly bind to miR-1305. Silencing of KLF5 or KLF5 inhibitor (ML264) suppressed PC cell viability and cell invasion, and enhanced cell apoptosis. KLF5 restrained miR-1305 transcription and expression by binding to its promoter region. miR-1305 exerted a suppressive effect on PC cell proliferation and apoptosis via regulation of the KLF5-ERBB2 axis; KLF5 gene is a transcriptional regulator of miR-1305, promising to be a new target for the diagnosis and treatment of PC.

ITGA5+ synovial fibroblasts orchestrate proinflammatory niche formation by remodelling the local immune microenvironment in rheumatoid arthritis

OBJECTIVES

To investigate the phenotypic heterogeneity of tissue-resident synovial fibroblasts and their role in inflammatory response in rheumatoid arthritis (RA).

METHODS

We used single-cell and spatial transcriptomics to profile synovial cells and spatial gene expressions of synovial tissues to identify phenotypic changes in patients with osteoarthritis, RA in sustained remission and active state. Immunohistology, multiplex immunofluorescence and flow cytometry were used to identify synovial fibroblasts subsets. Deconvolution methods further validated our findings in two cohorts (PEAC and R4RA) with treatment response. Cell coculture was used to access the potential cell-cell interactions. Adoptive transfer of synovial cells in collagen-induced arthritis (CIA) mice and bulk RNA sequencing of synovial joints further validate the cellular functions.

RESULTS

We identified a novel tissue-remodelling CD45-CD31-PDPN+ITGA5+ synovial fibroblast population with unique transcriptome of POSTN, COL3A1, CCL5 and TGFB1, and enriched in immunoregulatory pathways. This subset was upregulated in active and lympho-myeloid type of RA, associated with an increased risk of multidrug resistance. Transforming growth factor (TGF)-β1 might participate in the differentiation of this subset. Moreover, ITGA5+ synovial fibroblasts might occur in early stage of inflammation and induce the differentiation of CXCL13hiPD-1hi peripheral helper T cells (TPHs) from naïve CD4+ T cells, by secreting TGF-β1. Intra-articular injection of ITGA5+ synovial fibroblasts exacerbates RA development and upregulates TPHs in CIA mice.

CONCLUSIONS

We demonstrate that ITGA5+ synovial fibroblasts might regulate the RA progression by inducing the differentiation of CXCL13hiPD-1hi TPHs and remodelling the proinflammatory microenvironments. Therapeutic modulation of this subpopulation could therefore be a potential treatment strategy for RA.

Transcription factor specificity protein (SP) family in renal physiology and diseases

Dysregulated specificity proteins (SPs), members of the C2H2 zinc-finger family, are crucial transcription factors (TFs) with implications for renal physiology and diseases. This comprehensive review focuses on the role of SP family members, particularly SP1 and SP3, in renal physiology and pathology. A detailed analysis of their expression and cellular localization in the healthy human kidney is presented, highlighting their involvement in fatty acid metabolism, electrolyte regulation, and the synthesis of important molecules. The review also delves into the diverse roles of SPs in various renal diseases, including renal ischemia/reperfusion injury, diabetic nephropathy, renal interstitial fibrosis, and lupus nephritis, elucidating their molecular mechanisms and potential as therapeutic targets. The review further discusses pharmacological modulation of SPs and its implications for treatment. Our findings provide a comprehensive understanding of SPs in renal health and disease, offering new avenues for targeted therapeutic interventions and precision medicine in nephrology.

METTL10 attenuates adriamycin-induced podocyte injury by targeting cell dedifferentiation

Chronic kidney disease (CKD) is a worldwide public health problem. Podocyte damage is a hallmark of glomerular diseases including focal segmental glomerulosclerosis (FSGS) and one of the leading causes of CKD. Lysine methylation is a crucial post-translational modification. Beyond epidemic regulation, various lysine methyltransferases have been recently reported to participate in disease progression, including cancers and kidney diseases. Among them, Methyltransferase-like 10 (METTL10), is recognized as a gene associated with estimated glomerular filtration rate (eGFR) and CKD risk. However, its role in podocyte damage remains unclear. We identified the differentially expressed genes(DEGs)in podocyte injury by bioinformatics analysis. Patients diagnosed as idiopathic FSGS by renal biopsy were enrolled. Mouse model was established by Adriamycin(ADR) and urinary albumin/ creatinine ratio(UACR) was detected. Murine podocyte cell line was stimulated with ADR. We determined METTL10 was one of the significantly downregulated genes in damaged podocytes, confirmed the decreased glomerular expression of METTL10 in patients with idiopathic FSGS and in mice with ADR-induced nephrosis, respectively. Moreover, we found a negative correlation between glomerular METTL10 levels and UACR in mice. METTL10 was reduced in ADR-treated podocytes, accompanied by podocyte dedifferentiation (loss of synaptopodin, podocin, nephrin, WT-1) and acquisition of mesenchymal cell markers (snail, desmin, pax2). Knockdown of METTL10 promoted their dedifferentiation. METTL10 regulates podocyte dedifferentiation under damaging stimuli and protects podocytes.

USP11 promotes renal tubular cell pyroptosis and fibrosis in UUO mice via inhibiting KLF4 ubiquitin degradation

The pyroptosis of renal tubular epithelial cells leads to tubular loss and inflammation and then promotes renal fibrosis. The transcription factor Krüppel-like factor 4 (KLF4) can bidirectionally regulate the transcription of target genes. Our previous study revealed that sustained elevation of KLF4 is responsible for the transition of acute kidney injury (AKI) into chronic kidney disease (CKD) and renal fibrosis. In this study, we explored the upstream mechanisms of renal tubular epithelial cell pyroptosis from the perspective of posttranslational regulation and focused on the transcription factor KLF4. Mice were subjected to unilateral ureteral obstruction (UUO) surgery and euthanized on D7 or D14 for renal tissue harvesting. We showed that the pyroptosis of renal tubular epithelial cells mediated by both the Caspase-1/GSDMD and Caspase-3/GSDME pathways was time-dependently increased in UUO mouse kidneys. Furthermore, we found that the expression of the transcription factor KLF4 was also upregulated in a time-dependent manner in UUO mouse kidneys. Tubular epithelial cell-specific Klf4 knockout alleviated UUO-induced pyroptosis and renal fibrosis. In Ang II-treated mouse renal proximal tubular epithelial cells (MTECs), we demonstrated that KLF4 bound to the promoter regions of Caspase-3 and Caspase-1 and directly increased their transcription. In addition, we found that ubiquitin-specific protease 11 (USP11) was increased in UUO mouse kidneys. USP11 deubiquitinated KLF4. Knockout of Usp11 or pretreatment with the USP11 inhibitor mitoxantrone (3 mg/kg, i.p., twice a week for two weeks before UUO surgery) significantly alleviated the increases in KLF4 expression, pyroptosis and renal fibrosis. These results demonstrated that the increased expression of USP11 in renal tubular cells prevents the ubiquitin degradation of KLF4 and that elevated KLF4 promotes inflammation and renal fibrosis by initiating tubular cell pyroptosis.

Knockdown of KLF6 ameliorates myocardial infarction by regulating autophagy via transcriptional regulation of PTTG1

Krüppel-like factor 6 (KLF6) knockdown provides protection against kidney ischemia/reperfusion injury and ischemic stroke. However, it is unclear whether it plays a role in myocardial infarction (MI). Here, the expression of KLF6 was analyzed using the Gene Expression Omnibus (GEO) database and determined in patients with MI. The impact of KLF6 knockdown was further confirmed in in vivo and in vitro models of MI. The interaction between KLF6 and pituitary tumor-transforming gene 1 (PTTG1) was also evaluated. According to the GEO database, KLF6 expression was found to be upregulated in mouse hearts after MI compared to sham-operated mice. The upregulation of KLF6 in hearts from mice post-MI and in patients with MI was confirmed. KLF6 knockdown was found to alleviate myocardial injury, diminish infarct size, and suppress apoptosis and autophagy in mice with MI. In addition, inactivation of the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) signaling was observed after KLF6 knockdown in mice with MI. In an in vitro model of MI, the knockdown of KLF6 increased cell survival and inhibited autophagy through the AMPK/mTOR pathway. In addition, KLF6 interacted with the promoter of PTTG1 and negatively regulated its expression. Knockdown of PTTG1 abolished the function of KLF6 knockdown in vitro. This study demonstrates the protective effect of KLF6 knockdown against MI, which is attributed to the elevation of PTTG1 expression and inhibition of the AMPK/mTOR pathway. These findings provide a novel insight into MI treatment.NEW & NOTEWORTHY Our study demonstrates for the first time the role of Krüppel-like factor 6 (KLF6)/PTTG1 axis in myocardial infarction (MI). This study demonstrates the protective effect of KLF6 knockdown against MI, which is attributed to the elevation of PTTG1 expression and inhibition of the AMPK/mTOR pathway. These findings provide a novel insight into MI treatment.

Bioactive Flavonoids in Protecting Against Endothelial Dysfunction and Atherosclerosis

Atherosclerosis is a common cardiovascular disease closely associated with factors such as hyperlipidaemia and chronic inflammation. Among them, endothelial dysfunction serves as a major predisposing factor. Vascular endothelial dysfunction is manifested by impaired endothelium-dependent vasodilation, enhanced oxidative stress, chronic inflammation, leukocyte adhesion and hyperpermeability, endothelial senescence, and endothelial-mesenchymal transition (EndoMT). Flavonoids are known for their antioxidant activity, eliminating oxidative stress induced by reactive oxygen species (ROS), thereby preventing the oxidation of low-density lipoprotein (LDL) cholesterol, reducing platelet aggregation, alleviating ischemic damage, and improving vascular function. Flavonoids have also been shown to possess anti-inflammatory activity and to protect the cardiovascular system. This review focuses on the protective effects of these naturally-occuring bioactive flavonoids against the initiation and progression of atherosclerosis through their effects on endothelial cells including, but not limited to, their antioxidant, anti-inflammatory, anti-thrombotic, and lipid-lowering properties. However, more clinical evidences are still needed to determine the exact role and optimal dosage of these compounds in the treatment of atherosclerosis.

KLF5 silencing restrains proliferation, invasion, migration and angiogenesis of gallbladder carcinoma cells by transcriptional regulation of PDGFA

BACKGROUND

Krüppel-like factor 5 (KLF5) is recognized as a tumor mediator in multiple types of tumors. Nevertheless, whether KLF5 plays a role in gallbladder cancer (GBC) remains to be elucidated. This study aims to clarify the role of KLF5 in the proliferation, migration and angiogenesis in GBC cells.

METHODS

The expressions of KLF5 and platelet-derived growth factor subunit A (PDGFA) in GBC cell lines were analyzed by qRT-PCR and western blot assay. Cell proliferation was assessed utilizing the Cell Counting Kit-8 assay and EDU staining. Cell apoptosis was evaluated using flow cytometry, and apoptosis-related proteins was examined by western blotting. The migratory and invasive capabilities were evaluated utilizing wound healing and Transwell. Angiogenesis was assessed by ELISA, tube formation assay and western blot. The interaction between KLF5 and PDGFA was confirmed by ChIP assay, as well as luciferase reporter assay.

RESULTS

In this study, we discovered that the levels of KLF5 and PDGFA were upregulated in GBC cells. Silencing of KLF5 reduced the viability and suppressed the proliferation of GBC cells, as well as promoting the apoptosis. In addition, KLF5 silencing restrained the invasion and migration and angiogenesis in NOZ and GBC-SD cells. KLF5 transcription activated PDGFA expression and KLF5 was proved to bind to PDGFA promoter in NOZ cells. Following the silencing of PDGFA, the proliferation, invasion, migration, angiogenesis and apoptosis exhibited similar changes to KLF5 silencing. Additionally, PDGFA overexpression reversed the effects of KLF5 silencing on NOZ cells.

CONCLUSION

Collectively, our results suggest that KLF5 regulates GBC cell proliferation, invasion, migration, angiogenesis, as well as apoptosis, via mediating PDGFA transcriptionally, which might provide a novel therapeutic strategy for treatment of human GBC.

Exploring the Functionality of the Krüppel-like Factors in Kidney Development, Metabolism, and Diseases

The kidneys contribute to the overall health of an organism by maintaining systemic homeostasis. This process involves various biological mechanisms, in which the Krüppel-like factors (KLFs), a family of transcription factors, are essential for regulating development, differentiation, proliferation, and cellular apoptosis. They also play a role in the metabolic regulation of essential nutrients, such as glucose and lipids. The dysregulation of these transcription factors is associated with the development of various pathologies, which can ultimately lead to renal fibrosis, severely compromising kidney function. In this context, the present article provides a comprehensive review of the existing literature, offering an enriching analysis of the findings related to the role of KLFs in nephrology, while also highlighting their potential therapeutic role in the treatment of renal diseases.

A Small Molecule Agonist of Krüppel-Like Factor 15 in Proteinuric Kidney Disease

Key Points

A human podocyte-based high-throughput screen identified a novel agonist of Krüppel-like factor 15 (BT503), independent of glucocorticoid signaling. BT503 demonstrated renoprotective effects in three independent proteinuric kidney murine models. BT503 directly binds to inhibitor of nuclear factor kappa-B kinase subunit beta to inhibit NF-κB activation, which, subsequently restores Krüppel-like factor 15 under cell stress.

Background

Podocyte loss is the major driver of primary glomerular diseases such as FSGS. While systemic glucocorticoids remain the initial and primary therapy for these diseases, high-dose and chronic use of glucocorticoids is riddled with systemic toxicities. Krüppel-like factor 15 (KLF15) is a glucocorticoid-responsive gene, which is essential for the restoration of mature podocyte differentiation markers and stabilization of actin cytoskeleton in the setting of cell stress. Induction of KLF15 attenuates podocyte injury and glomerulosclerosis in the setting of cell stress.

Methods

A cell-based high-throughput screen with a subsequent structure–activity relationship study was conducted to identify novel agonists of KLF15 in human podocytes. Next, the agonist was tested in cultured human podocytes under cell stress and in three independent proteinuric models (LPS, nephrotoxic serum nephritis, and HIV-1 transgenic mice). A combination of RNA sequencing and molecular modeling with experimental validation was conducted to demonstrate the direct target of the agonist.

Results

The high-throughput screen with structure–activity relationship study identified BT503, a urea-based compound, as a novel agonist of KLF15, independent of glucocorticoid signaling. BT503 demonstrated protective effects in cultured human podocytes and in three independent proteinuric murine models. Subsequent molecular modeling with experimental validation shows that BT503 targets the inhibitor of nuclear factor kappa-B kinase complex by directly binding to inhibitor of nuclear factor kappa-B kinase subunit beta to inhibit canonical NF-κB signaling, which, in turn, restores KLF15 under cell stress, thereby rescuing podocyte loss and ameliorating kidney injury.

Conclusions

By developing and validating a cell-based high-throughput screen in human podocytes, we identified a novel agonist for KLF15 with salutary effects in proteinuric murine models through direct inhibition of inhibitor of nuclear factor kappa-B kinase subunit beta kinase activity.

Biochanin A suppresses Klf6-mediated Smad3 transcription to attenuate renal fibrosis in UUO mice

BACKGROUND

Renal fibrosis is a hallmark of chronic kidney disease (CKD). Smad3 serves as the principal transcription factor mediating the pro-fibrosis effects of TGF-β signaling in renal fibrosis. Biochanin A (BCA), a natural isoflavone, has been shown to attenuate renal fibrosis by inhibiting TGF-β signaling but the detailed mechanisms remain unresolved. This study aimed to elucidate the specific mechanisms by which BCA modulates TGF-β signaling.

METHODS

Renal fibrosis models were established both in vitro, using TGF-β1-stimulated mouse renal tubular TCMK1 cells, and in vivo, employing mice with unilateral ureter obstruction (UUO). RNA-seq was conducted to identify BCA-regulated genes. The AnimalTFDB4.0 database was utilized to predict transcription factors with potential binding to Smad3 promoter. The activities of TGF-β signaling and the cloned mouse Smad3 promoter were assessed using luciferase reporter assays. Plasmid transfection was performed using polyethylenimine in TCMK1 cells or ultrasound microbubbles in UUO kidneys. Gene expression was analyzed by RT-PCR, western blot, and immunohistochemistry assays.

RESULTS

BCA significantly inhibited TGF-β signaling activity and suppressed TGF-β1-induced fibrotic gene expression in TCMK1 cells. RNA-seq and in silico analyses identified Smad3 as the key gene downregulated by BCA, while leaving Smad2 unaffected. This selective transcriptional suppression of Smad3 by BCA was validated by luciferase reporter assays using the cloned Smad3 promoter. Furthermore, transcription factor binding prediction identified that Klf6, a transcription factor downregulated by BCA, has binding potential to the Smad3 promoter and promotes Smad3 transcription. Klf6 expression was induced in TGF-β1-stimulated TCMK1 cells and UUO kidneys, but this induction was abolished upon BCA treatment. Importantly, Klf6 overexpression restored Smad3 expression and counteracted the anti-fibrosis effects of BCA in both TGF-β1-stimulated TCMK1 cells and UUO kidneys.

CONCLUSION

TGF-β-responsive Klf6 transcriptionally transactivates Smad3 expression. BCA exerts anti-renal fibrosis effects by inhibiting the Klf6-Smad3 signaling axis, underscoring its therapeutic potential in the treatment of CKD.

Krüppel-like factor 4 modulates the miR-101/COL10A1 axis to inhibit renal fibrosis after AKI by regulating epithelial-mesenchymal transition

Acute kidney injury (AKI) can progress to renal fibrosis and chronic kidney disease (CKD), which reduces quality of life and increases the economic burden on patients. However, the molecular mechanisms underlying renal fibrosis following AKI remain unclear. This study tested the hypothesis that the Krüppel-like factor 4 (KLF4)/miR-101/Collagen alpha-1X (COL10A1) axis could inhibit epithelial-mesenchymal transition (EMT) and renal fibrosis after AKI in a mouse model of ischemia-reperfusion (I/R)-induced renal fibrosis and HK-2 cells by gene silencing, overexpression, immunofluorescence, immunohistochemistry, real-time quantitative PCR, Western blotting, dual-luciferase reporter assay, fluorescence in situ hybridization (FISH) and ELISA. Compared with the Sham group, I/R induced renal tubular and glomerular injury and fibrosis, and increased the levels of BUN, serum Scr and neutrophil gelatinase-associated lipocalin (NGAL), Col10a1 and Vimentin expression, but decreased E-cadherin expression in the kidney tissues of mice at 42 days post-I/R. Similarly, hypoxia promoted fibroblastic morphological changes in HK-2 cells and enhanced NGAL, COL10A1, Vimentin, and α-SMA expression, but reduced E-cadherin expression in HK-2 cells. These pathological changes were significantly mitigated in COL10A1-silenced renal tissues and HK-2 cells. KLF4 induces miR-101 transcription. More importantly, hypoxia upregulated Vimentin and COL10A1 expression, but decreased miR-101, KLF4, and E-cadherin expression in HK-2 cells. These hypoxic effects were significantly mitigated or abrogated by KLF4 over-expression in the HK-2 cells. Our data indicate that KLF4 up-regulates miR-101 expression, leading to the downregulation of COL10A1 expression, inhibition of EMT and renal fibrosis during the pathogenic process of I/R-related renal fibrosis.

KLF7 Promotes Hepatocellular Carcinoma Progression Through Regulating SLC1A5-Mediated Tryptophan Metabolism

Krüppel-like factor 7 is a transcriptional activator and acts as an oncogene in human cancers, including hepatocellular carcinoma (HCC). Tryptophan metabolism is important for HCC cell proliferation, metastasis, and invasion. It is unclear whether KLF7 could regulate Trp metabolism in HCC. In this study, we found that Trp metabolism was suppressed in HCC cells with KLF7 knockdown. The mRNA and protein levels of SLC1A5, SLC7A5, and TPH1, as well as the content of Trp and serotonin, were reduced after KLF7 knockdown, and were potentiated following KLF7 overexpression. Increasing the content of serotonin could restore the malignancy of tumour cells in vitro and tumour growth in vivo. Conversely, decreasing the content of serotonin suppressed HCC cell proliferation. The binding activity of KLF7 was on the promoter of SLC1A5, and KLF7 positively regulated the expression of SLC1A5. KLF7 contributed to the proliferation and migration of HCC cells by up-regulation of SLC1A5. Collectively, KLF7 promotes the progression of HCC through regulating Trp metabolism. The newly identified axis of KLF7/ SLC1A5 in HCC could represent a potential target for HCC therapy.

Diagnostic and Prognostic Values of KLF5 and RUNX1 in Acute Kidney Injury in Septic Patients

Diagnostic and prognostic values of Kruppel-like factor 5 (KLF5) and Runt-related transcription factor 1 (RUNX1) were determined in sepsis-induced acute kidney injury (SI-AKI). The study included 120 septic patients and set two groups: SI-AKI group (n = 60) or non-AKI group (n = 60). Fasting venous blood was drawn, and KLF5 and RUNX1 levels were measured. The receiver operating characteristic curve was plotted for diagnostic evaluation of KLF5 and RUNX1 in SI-AKI. The correlation between KLF5 and RUNX1 and serum creatinine (Scr), cystatin C (Cys-C), and kidney injury molecule 1 (KIM-1) were assessed by Pearson method. Predictive values of KLF5 and RUNX1 in 28-day survival of SI-AKI patients were considered by Kaplan-Meier survival curves and multivariate Cox regression analysis. Serum KLF5 and RUNX1 in SI-AKI patients were upregulated. Serum KLF5 and RUNX1 were of high diagnostic value in distinguishing SI-AKI patients from non-AKI patients. KLF5 and RUNX1 were in a positive correlation with Scr, Cys-C, and KIM-1, respectively. The 28-day survival of SI-AKI patients with high serum KLF5 or RUNX1 expression was poor, and serum KLF5 and RUNX1 expression were independently correlated with SI-AKI patients' survival. KLF5 and RUNX1 have diagnostic and prognostic values in SI-AKI patients.

KLF15 suppresses stemness of pancreatic cancer by decreasing USP21-mediated Nanog stability

The existence of cancer stem cells (CSCs) in pancreatic ductal adenocarcinoma (PDAC) is considered to be the key factor for metastasis and chemoresistance. Thus, novel therapeutic strategies for eradicating CSCs are urgently needed. Here we aimed to explore the role of KLF15 in stemness and the feasibility of using KLF15 to inhibit CSCs and improve chemotherapy sensitivity in PDAC. In this study, we report that KLF15 is negatively associated with poor survival and advanced pathological staging of PDAC. Moreover, tumorous KLF15 suppresses the stemness of PDAC by promoting the degradation of Nanog, and KLF15 directly interacts with Nanog, inhibiting interaction between Nanog with USP21. We also demonstrate that the KLF15/Nanog complex inhibit the stemness in vivo and in PDX cells. Tazemetostat suppresses stemness and sensitizes PDAC cells to gemcitabine by promoting KLF15 expression in PDAC. In summary, the findings of our study confirm the value of KLF15 level in diagnosis and prognosis of PDAC, it is the first time to explore the inhibition role of KLF15 in stemness of PDAC and the regulation mechanism of Nanog, contributing to provide a new therapeutic strategy that using Tazemetostat sensitizes PDAC cells to gemcitabine by promoting KLF15 expression for PDAC.

Krüppel-like factors family in health and disease

Krüppel-like factors (KLFs) are a family of basic transcription factors with three conserved Cys2/His2 zinc finger domains located in their C-terminal regions. It is acknowledged that KLFs exert complicated effects on cell proliferation, differentiation, survival, and responses to stimuli. Dysregulation of KLFs is associated with a range of diseases including cardiovascular disorders, metabolic diseases, autoimmune conditions, cancer, and neurodegenerative diseases. Their multidimensional roles in modulating critical pathways underscore the significance in both physiological and pathological contexts. Recent research also emphasizes their crucial involvement and complex interplay in the skeletal system. Despite the substantial progress in understanding KLFs and their roles in various cellular processes, several research gaps remain. Here, we elucidated the multifaceted capabilities of KLFs on body health and diseases via various compliable signaling pathways. The associations between KLFs and cellular energy metabolism and epigenetic modification during bone reconstruction have also been summarized. This review helps us better understand the coupling effects and their pivotal functions in multiple systems and detailed mechanisms of bone remodeling and develop potential therapeutic strategies for the clinical treatment of pathological diseases by targeting the KLF family.

A review of KLF4 and inflammatory disease: Current status and future perspective

Inflammation is the response of the human body to injury, infection, or other abnormal states, which is involved in the development of many diseases. As a member of the Krüppel-like transcription factors (KLFs) family, KLF4 plays a crucial regulatory role in physiological and pathological processes due to its unique dual domain of transcriptional activation and inhibition. A growing body of evidence has demonstrated that KLF4 plays a pivotal role in the pathogenesis of various inflammatory disorders, including inflammatory bowel disease, osteoarthritis, renal inflammation, pneumonia, neuroinflammation, and so on. Consequently, KLF4 has emerged as a promising new therapeutic target for inflammatory diseases. This review systematically generalizes the molecular regulatory network, specific functions, and mechanisms of KLF4 to elucidate its complex roles in inflammatory diseases. An in-depth study on the biological function of KLF4 is anticipated to offer a novel research perspective and potential intervention strategies for inflammatory diseases.

Prognostic value of KLFs family genes in renal clear cell carcinoma

Numerous studies have shown that the Krüppel-like factors (KLFs) family of transcription factors regulate various eukaryotic physiological processes including the proliferation, differentiation, senescence, death, and carcinogenesis of animal cells. In addition, they are involved in the regulation of key biological processes such as cell cycle, DNA repair, and immune response. Current studies focus on investigating the role of KLFs in normal physiological conditions and the incidence and development of diseases. However002C the significance of KLFs family genes in clear cell renal cell carcinoma (ccRCC) remains partly understood; therefore, an in-depth investigation of their role and clinical value in this cancer is desired. The study aimed to investigate the role of KLF family genes in the incidence, development, and prognosis of ccRCC, and to identify the related potential biomarkers and therapeutic targets. The expression of KLFs in the RNA sequencing data of 613 ccRCCs from the TCGA database was analyzed using R software, and UALCAN and GEPIA assessed the expression of KLF genes in ccRCC. Real-time fluorescence quantitative PCR analysis was performed using 10 pairs of paired ccRCC sample tissues and renal cancer cell lines from the First Affiliated Hospital of Nanchang University. Overall survival (OS), progression-free interval (PFI), and disease-specific survival (DSS) of Kidney Clear Cell Carcinoma (KIRC) samples at differential expressions of KLFs in the TCGA database were analyzed using the R software, followed by generating a nomogram prediction model. GSCALite assessed the interactions of KLF genes with miRNAs and generated network maps. Protein interaction network maps of 50 neighboring genes associated with KLF mutations were analyzed using STRING with GO and KEGG functional enrichment analyses. The cBioPortal determined the probability of KLF gene mutations and their impact on OS and disease-free survival (DFS) in patients with ccRCC. Immune cell infiltration of KLFs was analyzed using TIMER. Finally, GSCALite was used to analyze the drug sensitivity and associated pathways of action of KLFs. Correlation validation using cellular experiments. KLF3/5/9/15 were significantly downregulated in ccRCC tissues, whereas KLF16/17 were upregulated compared with the adjacent tissues. Patients with high mRNA levels of KLF16/17 showed significantly lower OS, PFI, and DSS, whereas KLF3/5/9 showed a reverse trend. In patients with ccRCC, a significant correlation was observed between KLF mutations and OS and DSS. Furthermore, the correlation of KLF3/5/9 with immune cell infiltration was stronger than that of KLF15/16, while KLF17 was significantly associated with the Epithelial-Mesenchymal Transition (EMT) pathway. Overexpression of KLF5 inhibits the proliferative and migratory capacity of renal cancer cells (786-O and OS-RC-2), as well as their sensitivity to relevant small molecule drugs. Our research revealed the expression levels and biological significance of KLF genes in ccRCC, particularly highlighting the potential of KLF5 as a promising biomarker and therapeutic target for effective prognosis and diagnosis of ccRCC.

A single-cell profile reveals the transcriptional regulation responded for Abelmoschus manihot (L.) treatment in diabetic kidney disease

BACKGROUND

Huangkui capsule (HKC), as an ethanol extract of Abelmoschus manihot (L.), has a significant efficacy in treatment of the patients with diabetic kidney disease (DKD). The bioactive ingredients of HKC mainly include the flavonoids such as rutin, hyperoside, hibifolin, isoquercetin, myricetin, quercetin and quercetin-3-O-robinobioside.

PURPOSE

To explore the molecular mechanisms of A. manihot in treatment of DKD.

STUDY DESIGN

A single-cell RNA sequencing analysis of kidneys in db/db mice with and without HKC administration.

METHODS

Urinary biochemical and histopathological examination in C57BL/6 and db/db mice of DKD and HKC groups was done. Single-cell RNA sequencing pipeline was then performed. The regulatory mechanisms of seven flavonoids in HKC were revealed by cell communication, prediction of transcription factor regulatory network, and molecular docking.

RESULTS

By constructing ligand-receptor regulatory network and performing molecular docking between 75 receptors with different activities and seven flavonoids. 11 key receptors in 4 cell types (segment 3 proximal convoluted tubular cell, ascending limbs of the loop of Henle, distal convoluted tubule, and T cell) in kidneys were found to be directly interacted with HKC. The interactions regulated 8 downstream regulons. The docking receptors in T cell led to transcriptional event differences in the regulons such as Cebpb, Rel, Tbx21 and Klf2 and consequently affected the activation, differentiation, and infiltration of T cell, while the receptors Tgfbr1 and Ldlr in stromal cells of kidneys were closely associated with the downstream transcriptional events of renal injury and proteinuria in DKD.

CONCLUSION

The current study provides novel information of the key receptors and regulons in renal cells for a better understanding of the cell type specific molecular mechanisms of A. manihot in treatment of DKD.

Deletion of the endothelial glycocalyx component endomucin leads to impaired glomerular structure and function

Background

Endomucin (EMCN), an endothelial-specific glycocalyx component, was found to be highly expressed by the endothelium of the renal glomerulus. We reported an anti-inflammatory role of EMCN and its involvement in the regulation of vascular endothelial growth factor (VEGF) activity through modulating VEGF receptor 2 (VEGFR2) endocytosis. The goal of this study is to investigate the phenotypic and functional effects of EMCN deficiency using the first global EMCN knockout mouse model.

Methods

Global EMCN knockout mice were generated by crossing EMCN-floxed mice with ROSA26-Cre mice. Flow cytometry was employed to analyze infiltrating myeloid cells in the kidneys. The ultrastructure of the glomerular filtration barrier was examined by transmission electron microscopy, while urinary albumin, creatinine, and total protein levels were analyzed from freshly collected urine samples. Expression and localization of EMCN, EGFP, CD45, CD31, CD34, podocin, albumin, and α-smooth muscle actin were examined by immunohistochemistry. Mice were weighed regularly, and their systemic blood pressure was measured using a non-invasive tail-cuff system. Glomerular endothelial cells and podocytes were isolated by fluorescence-activated cell sorting for RNA-seq. Transcriptional profiles were analyzed to identify differentially expressed genes in both endothelium and podocytes, followed by gene ontology analysis of up- and down-regulated genes. Protein levels of EMCN, albumin, and podocin were quantified by Western blot.

Results

EMCN -/- mice were viable with no gross anatomical defects in kidneys. The EMCN -/- mice exhibited increased infiltration of CD45 + cells, with an increased proportion of Ly6G high Ly6C high myeloid cells and higher VCAM-1 expression. EMCN -/- mice displayed albuminuria with increased albumin in the Bowman's space compared to the EMCN +/+ littermates. Glomeruli in EMCN -/- mice revealed fused and effaced podocyte foot processes and disorganized endothelial fenestrations. We found no significant difference in blood pressure between EMCN knockout mice and their wild-type littermates. RNA-seq of glomerular endothelial cells revealed downregulation of cell-cell adhesion and MAPK/ERK pathways, along with glycocalyx and extracellular matrix remodeling. In podocytes, we observed reduced VEGF signaling and alterations in cytoskeletal organization. Notably, there was a significant decrease in both mRNA and protein levels of podocin, a key component of the slit diaphragm.

Conclusion

Our study demonstrates a critical role of the endothelial marker EMCN in supporting normal glomerular filtration barrier structure and function by maintaining glomerular endothelial tight junction and homeostasis and podocyte function through endothelial-podocyte crosstalk.

KLF15-activated MARCH2 boosts cell proliferation and epithelial-mesenchymal transition and presents diagnostic significance for hepatocellular carcinoma

PURPOSE

Membrane associated ubiquitin ligase MARCH2 majorly involves in inflammation response and protein trafficking. However, its comprehensive role in hepatocellular carcinoma (HCC) is largely unknown.

METHODS

Firstly, multiple bioinformatic analyses were applied to determine MARCH2 mRNA level, its expression comparison in diverse molecular and immune subtypes, and diagnostic value in HCC. Subsequently, RNA-seq, real-time quantitative PCR, immunohistochemistry and cell proliferation assay are used to explore the epithelial-mesenchymal transition (EMT) and proliferation by gene-silencing or overexpressing in cultured HCC cells or in vivo xenograft. Moreover, dual luciferase reporter assay and immunoblotting are delved into verify the transcription factor that activating MARCH2 promoter.

RESULTS

Multiple bioinformatic analyses demonstrate that MARCH2 is upregulated in multiple cancer types and exhibits startling diagnostic value as well as distinct molecular and immune subtypes in HCC. RNA-seq analysis reveals MARCH2 may promote EMT, cell proliferation and migration in HepG2 cells. Furthermore, overexpression of MARCH2 triggers EMT and significantly enhances HCC cell migration, proliferation and colony formation in a ligase activity-dependent manner. Additionally, above observations are validated in the HepG2 mice xenografts. For up-stream mechanism, transcription factor KLF15 is highly expressed in HCC and activates MARCH2 expression.

CONCLUSION

KLF15 activated MARCH2 triggers EMT and serves as a fascinating biomarker for precise diagnosis of HCC. Consequently, MARCH2 emerges as a promising candidate for target therapy in cancer management.

Hypoxia-inducible factor-1α attenuates renal podocyte injury in male rats in a simulated high-altitude environment by upregulating Krüppel-like factor 4 expression

Previous studies have shown that podocyte injury is involved in the development of proteinuria in rats under hypobaric hypoxia conditions. Prolyl hydroxylase inhibitors (PHIs) may reduce proteinuria. This study aimed to further investigate whether the protective effects of hypoxia-inducible factor 1α (HIF1α) on podocyte injury induced by hypobaric hypoxia are related to Krüppel-like factor 4 (KLF4). Rats were housed in a low-pressure oxygen chamber to simulate a high-altitude environment (5000 m), and a PHI was intraperitoneally injected. Urinary protein electrophoresis was performed and the morphology of the podocytes was observed by electron microscopy. Rat podocytes were cultured under 1% O2, and siRNA was used to interfere with KLF4 expression. The protein expression levels of HIF1α, KLF4, CD2-associated protein (CD2AP) and nephrin were determined by western blotting. Compared with those in the experimental group, the rats in the intervention group on day 14 had lower urinary protein levels, increased protein expression levels of CD2AP and nephrin, and reduced podocyte injury. The results of in vitro experiments showed that the protein expression levels of KLF4, CD2AP and nephrin were greater in the PHI intervention group and lower in the HIF1α inhibitors group than in the low-oxygen group. The protein expression of CD2AP and nephrin in the siKLF4-transfected podocytes treated with PHI and HIF1α inhibitors did not differ significantly from that in the low-oxygen group. HIF1α may be involved in reducing progressive high-altitude proteinuria by regulating KLF4 expression and contributing to the repair of podocyte injury induced by hypobaric hypoxia.

Tripterygium drug-loaded liposome alleviates renal function by promoting vascularization and inhibiting fibrosis

Introduction: Tripterygium species have been traditionally used in Chinese medicine for treating various conditions. The aim of the study was to construct a drug-modified renal infarction targeting liposome (rTor-LIP) containing Tripterygium in order to improve the therapeutic effect on renal injury. Methods: rTor-LIP was prepared using the extruder method containing Tripterygium solution. The preparation was characterized by transmission electron microscopy, Marvin laser particle size analyzer, and Western blotting. In vitro experiments were conducted to verify the biocompatibility of rTor-LIP, and in vivo experiments were conducted to verify the therapeutic effect of rTor- LIP on renal injury. Results and discussion: The surface of rTor-LIP was regular and oval. In vitro results showed that after co-incubation with rTor-LIP, endothelial cells did not show significant apoptosis, and there were no significant abnormalities in the mitochondrial metabolism. The in vivo results showed that the morphology of endothelial cells in the rTor-LIP group was uniform and the cytoplasmic striations were clear, but the local striations had disappeared. Thus, rTor-LIP nano-targeted liposomes can effectively target hypoxic kidney tissue, providing a new idea for the treatment of renal infarction.

CD226 promotes renal fibrosis by regulating macrophage activation and migration

It has been found that CD226 plays an important role in regulating macrophage function, but its expression and function in macrophages during renal fibrogenesis have not been studied. Our data demonstrated that CD226 expression in macrophages was obviously upregulated in the unilateral ureteral obstruction model, while CD226 deficiency attenuated collagen deposition in renal interstitium along with fewer M1 within renal cortex and renal medulla and a lower level of proinflammatory factors compared to that of control littermates. Further studies demonstrated that Cd226-/- bone marrow-derived macrophages transferring could significantly reduce the tubular injury, collagen deposition, and proinflammatory cytokine secretion compared with that of Cd226+/+ bone marrow-derived macrophages transferring in the unilateral ureteral obstruction model. Mechanistic investigations revealed that CD226 promoted proinflammatory M1 macrophage accumulation in the kidney via suppressing KLF4 expression in macrophages. Therefore, our results uncovered a pathogenic role of CD226 during the development of chronic kidney disease by promoting monocyte infiltration from peripheral blood into the kidney and enhancing macrophage activation toward the inflammatory phenotype by suppressing KLF4 expression.

KLF4 Suppresses the Progression of Hepatocellular Carcinoma by Reducing Tumor ATP Synthesis through Targeting the Mir-206/RICTOR Axis

To address the increased energy demand, tumor cells undergo metabolic reprogramming, including oxidative phosphorylation (OXPHOS) and aerobic glycolysis. This study investigates the role of Kruppel-like factor 4 (KLF4), a transcription factor, as a tumor suppressor in hepatocellular carcinoma (HCC) by regulating ATP synthesis. Immunohistochemistry was performed to assess KLF4 expression in HCC tissues. Functional assays, such as CCK-8, EdU, and colony formation, as well as in vivo assays, including subcutaneous tumor formation and liver orthotopic xenograft mouse models, were conducted to determine the impact of KLF4 on HCC proliferation. Luciferase reporter assay and chromatin immunoprecipitation assay were utilized to evaluate the interaction between KLF4, miR-206, and RICTOR. The findings reveal low KLF4 expression in HCC, which is associated with poor prognosis. Both in vitro and in vivo functional assays demonstrate that KLF4 inhibits HCC cell proliferation. Mechanistically, it was demonstrated that KLF4 reduces ATP synthesis in HCC by suppressing the expression of RICTOR, a core component of mTORC2. This suppression promotes glutaminolysis to replenish the TCA cycle and increase ATP levels, facilitated by the promotion of miR-206 transcription. In conclusion, this study enhances the understanding of KLF4's role in HCC ATP synthesis and suggests that targeting the KLF4/miR-206/RICTOR axis could be a promising therapeutic approach for anti-HCC therapeutics.

A protective role of nintedanib in peritoneal fibrosis through H19-EZH2-KLF2 axis via impeding mesothelial-to-mesenchymal transition

BACKGROUND

Peritoneal fibrosis (PF), a common complication of long-term peritoneal dialysis, accounts for peritoneal ultrafiltration failure to develop into increased mortality. Nintedanib has previously been shown to protect against multi-organ fibrosis, including PF. Unfortunately, the precise molecular mechanism underlying nintedanib in the pathogenesis of PF remains elusive.

METHODS

The mouse model of PF was generated by chlorhexidine gluconate (CG) injection with or without nintedanib administration, either with the simulation for the cell model of PF by constructing high-glucose (HG)-treated human peritoneal mesothelial cells (HPMCs). HE and Masson staining were applied to assess the histopathological changes of peritoneum and collagen deposition. FISH, RT-qPCR, western blot and immunofluorescence were employed to examine distribution or expression of targeted genes. Cell viability was detected using CCK-8 assay. Cell morphology was observed under a microscope. RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays were applied to validate the H19-EZH2-KLF2 regulatory axis.

RESULTS

Aberrantly overexpressed H19 was observed in both the mouse and cell model of PF, of which knockdown significantly blocked HG-induced mesothelial-to-mesenchymal transition (MMT) of HPMCs. Moreover, loss of H19 further strengthened nintedanib-mediated suppressive effects against MMT process in a mouse model of PF. Mechanistically, H19 could epigenetically repressed KLF2 via recruiting EZH2. Furthermore, TGF-β/Smad pathway was inactivated by nintedanib through mediating H19/KLF2 axis.

CONCLUSION

In summary, nintedanib disrupts MMT process through regulating H19/EZH2/KLF2 axis and TGF-β/Smad pathway, which laid the experimental foundation for nintedanib in the treatment of PF.

Machine learning application identifies plasma markers for proteinuria in metastatic colorectal cancer patients treated with Bevacizumab

BACKGROUND AND OBJECTIVES

Proteinuria is a common complication after the application of bevacizumab therapy in patients with metastatic colorectal cancer, and severe proteinuria can lead to discontinuation of the drug. There is a lack of sophisticated means to predict bevacizumab-induced proteinuria, so the present study aims to predict bevacizumab-induced proteinuria using peripheral venous blood samples.

METHODS

A total of 122 subjects were enrolled and underwent pre-treatment plasma markers, and we followed them for six months with proteinuria as the endpoint event. We then analyzed the clinical features and plasma markers for grade ≥ 2 proteinuria occurrence using machine learning to construct a model with predictive utility.

RESULTS

One hundred sixteen subjects were included in the statistical analysis. We found that high baseline systolic blood pressure, low baseline HGF, high baseline ET1, high baseline MMP2, and high baseline ACE1 were risk factors for the development of grade ≥ 2 proteinuria in patients with metastatic colorectal cancer who received bevacizumab. Then, we constructed a support vector machine model with a sensitivity of 0.889, a specificity of 0.918, a precision of 0.615, and an F1 score of 0.727.

CONCLUSION

We constructed a machine learning model for predicting grade ≥ 2 bevacizumab-induced proteinuria, which may provide proteinuria risk assessment for applying bevacizumab in patients with metastatic colorectal cancer.

NSUN2 facilitates tenogenic differentiation of rat tendon-derived stem cells via m5C methylation of KLF2

Introduction

Tendon-derived stem cells (TDSCs) play a critical role in tendon repair. N5-methylcytosine (m5C) is a key regulator of cellular processes such as differentiation. This study aimed to investigate the impact of m5C on TDSC differentiation and the underlying mechanism.

Methods

TDSCs were isolated from rats and identified, and a tendon injury rat model was generated. Tenogenic differentiation in vitro was evaluated using Sirius red staining and quantitative real-time polymerase chain reaction, while that in vivo was assessed using immunohistochemistry and hematoxylin‒eosin staining. m5C methylation was analyzed using methylated RNA immunoprecipitation, dual-luciferase reporter assay, and RNA stability assay.

Results

The results showed that m5C levels and NSUN2 expression were increased in TDSCs after tenogenic differentiation. Knockdown of NSUN2 inhibited m5C methylation of KLF2 and decreased its stability, which was recognized by YBX1. Moreover, interfering with KLF2 suppressed tenogenic differentiation of TDSCs, which could be abrogated by KLF2 overexpression. Additionally, TDSCs after NSUN2 overexpression contributed to ameliorating tendon injury in vivo. In conclusion, NSUN2 promotes tenogenic differentiation of TDSCs via m5C methylation of KLF2 and accelerates tendon repair.

Conclusions

The findings suggest that overexpression of NSUN2 can stimulate the differentiation ability of TDSCs, which can be used in the treatment of tendinopathy.

Multi-Omic Analysis Reveals Genetic Determinants and Therapeutic Targets of Chronic Kidney Disease and Kidney Function

Chronic kidney disease (CKD) presents a significant global health challenge, characterized by complex pathophysiology. This study utilized a multi-omic approach, integrating genomic data from the CKDGen consortium alongside transcriptomic, metabolomic, and proteomic data to elucidate the genetic underpinnings and identify therapeutic targets for CKD and kidney function. We employed a range of analytical methods including cross-tissue transcriptome-wide association studies (TWASs), Mendelian randomization (MR), summary-based MR (SMR), and molecular docking. These analyses collectively identified 146 cross-tissue genetic associations with CKD and kidney function. Key Golgi apparatus-related genes (GARGs) and 41 potential drug targets were highlighted, with MAP3K11 emerging as a significant gene from the TWAS and MR data, underscoring its potential as a therapeutic target. Capsaicin displayed promising drug-target interactions in molecular docking analyses. Additionally, metabolome- and proteome-wide MR (PWMR) analyses revealed 33 unique metabolites and critical inflammatory proteins such as FGF5 that are significantly linked to and colocalized with CKD and kidney function. These insights deepen our understanding of CKD pathogenesis and highlight novel targets for treatment and prevention.

[Upregulating KLF11 ameliorates intestinal inflammation in mice with 2, 4, 6-trinitrobenesulfonic acid-induced colitis by inhibiting the JAK2/STAT3 signaling pathway]

OBJECTIVE

To investigate the expression level of Kruppel-like transcription factor family member KLF11 in intestinal mucosal tissues of Crohn's disease (CD) and its regulatory effect on intestinal inflammation in CD-like colitis.

METHODS

We examined KLF11 expression levels in diseased and normal colon mucosal tissues from 12 CD patients and 12 patients with colorectal cancer using immunofluorescence staining. KLF11 expression was also detected in the colon mucosal tissues of a mouse model of 2, 4, 6-trinitrobenesulfonic acid (TNBS)-induced colitis. A recombinant adenoviral vector was used to upregulate KLF11 expression in the mouse models and the changes in intestinal inflammation was observed. A Caco-2 cell model with stable KLF11 overexpression was constructed by lentiviral infection. The effect of KLF11 overexpression on expressions of JAK2/STAT3 signaling pathway proteins was investigated using immunoblotting in both the mouse and cell models. The mouse models were treated with coumermycin A1, a JAK2/STAT3 signaling pathway agonist, and the changes in intestinal inflammatory responses were observed.

RESULTS

The expression level of KLF11 was significantly lowered in both the clinical specimens of diseased colon mucosal tissues and the colon tissues of mice with TNBS-induced colitis (P < 0.05). Adenovirus-mediated upregulation of KLF11 significantly improved intestinal inflammation and reduced the expression levels of inflammatory factors in the intestinal mucosa of the colitis mouse models (P < 0.05). Overexpression of KLF11 significantly inhibited the expression levels of p-JAK2 and p-STAT3 in intestinal mucosal tissues of the mouse models and in Caco-2 cells (P < 0.05). Treatment with coumermycin A1 obviously inhibited the effect of KLF11 upregulation for improving colitis and significantly increased the expression levels of inflammatory factors in the intestinal mucosa of the mouse models (P < 0.05).

CONCLUSION

KLF11 is downregulated in the intestinal mucosa in CD, and upregulation of KLF11 can improve intestinal inflammation and reduce the production of inflammatory factors probably by inhibiting the JAK2/STAT3 signaling pathway.

KLF transcription factors in bone diseases

Krüppel-like factors (KLFs) are crucial in the development of bone disease. They are a family of zinc finger transcription factors that are unusual in containing three highly conserved zinc finger structural domains interacting with DNA. It has been discovered that it engages in various cell functions, including proliferation, apoptosis, autophagy, stemness, invasion and migration, and is crucial for the development of human tissues. In recent years, the role of KLFs in bone physiology and pathology has received adequate attention. In addition to regulating the normal growth and development of the musculoskeletal system, KLFs participate in the pathological process of the bones and joints and are intimately linked to several skeletal illnesses, such as osteoarthritis (OA), rheumatoid arthritis (RA), osteoporosis (OP) and osteosarcoma (OS). Consequently, targeting KLFs has emerged as a promising therapeutic approach for an array of bone disorders. In this review, we summarize the current literature on the importance of KLFs in the emergence and regulation of bone illnesses, with a particular emphasis on the pertinent mechanisms by which KLFs regulate skeletal diseases. We also discuss the need for KLFs-based medication-targeted treatment. These endeavours offer new perspectives on the use of KLFs in bone disorders and provide prognostic biomarkers, therapeutic targets and possible drug candidates for bone diseases.

Protective Role of the Podocyte IL-15 / STAT5 Pathway in Focal Segmental Glomerulosclerosis

Introduction

During glomerular diseases, podocyte-specific pathways can modulate the intensity of histological disease and prognosis. The therapeutic targeting of these pathways could thus improve the management and prognosis of kidney diseases. The Janus Kinase/Signal Transducer and Activator of Transcription (JAK/STAT) pathway, classically described in immune cells, has been recently described in detail in intrinsic kidney cells.

Methods

We describe STAT5 expression in human kidney biopsies from patients with focal segmental glomerulosclerosis (FSGS) and studied mice with a podocyte-specific Stat5 deletion in experimental glomerular diseases.

Results

Here, we show, for the first time, that STAT5 is activated in human podocytes in FSGS. In addition, podocyte-specific Stat5 inactivation aggravates the structural and functional alterations in a mouse model of FSGS. This could be due, at least in part, to an inhibition of autophagic flux. Finally, interleukin 15 (IL-15), a classical activator of STAT5 in immune cells, increases STAT5 phosphorylation in human podocytes, and its administration alleviates glomerular injury in vivo by maintaining autophagic flux in podocytes.

Conclusion

Activating podocyte STAT5 with commercially available IL-15 represents a potential new therapeutic avenue for FSGS.

Research progress in the role of gut microbiota in acute kidney injury

Acute kidney injury (AKI) remains a global public health problem with high incidence, high mortality rates, expensive medical costs, and limited treatment options. AKI can further progress to chronic kidney disease (CKD) and eventually end-stage renal disease (ESRD). Previous studies have shown that trauma, adverse drug reactions, surgery, and other factors are closely associated with AKI. With further in-depth exploration, the role of gut microbiota in AKI is gradually revealed. After AKI occurs, there are changes in the composition of gut microbiota, leading to disruption of the intestinal barrier, intestinal immune response, and bacterial translocation. Meanwhile, metabolites of gut microbiota can exacerbate the progression of AKI. Therefore, elucidating the specific mechanisms by which gut microbiota is involved in the occurrence and development of AKI can provide new insights from the perspective of intestinal microbiota for the prevention and treatment of AKI.

Acetyl-CoA synthetase 2 induces pyroptosis and inflammation of renal epithelial tubular cells in sepsis-induced acute kidney injury by upregulating the KLF5/NF-κB pathway

BACKGROUND

Pyroptosis of the renal tubular epithelial cells (RTECs) and interstitial inflammation are central pathological characteristics of acute kidney injury (AKI). Pyroptosis acts as a pro-inflammatory form of programmed cell death and is mainly dependent on activation of the NLRP3 inflammasome. Previous studies revealed that acetyl-CoA synthetase 2 (ACSS2) promotes inflammation during metabolic stress suggesting that ACSS2 might regulate pyroptosis and inflammatory responses of RTECs in AKI.

METHODS AND RESULTS

The expression of ACSS2 was found to be significantly increased in the renal epithelial cells of mice with lipopolysaccharide (LPS)-induced AKI. Pharmacological and genetic strategies demonstrated that ACSS2 regulated NLRP3-mediated caspase-1 activation and pyroptosis through the stimulation of the KLF5/NF-κB pathway in RTECs. The deletion of ACSS2 attenuated renal tubular pathological injury and inflammatory cell infiltration in an LPS-induced mouse model, and ACSS2-deficient mice displayed impaired NLRP3 activation-mediated pyroptosis and decreased IL-1β production in response to the LPS challenge. In HK-2 cells, ACSS2 deficiency suppressed NLRP3-mediated caspase-1 activation and pyroptosis through the downregulation of the KLF5/NF-κB pathway. The KLF5 inhibitor ML264 suppressed NF-κB activity and NLRP3-mediated caspase-1 activation, thus protecting HK-2 cells from LPS-induced pyroptosis.

CONCLUSION

Our results suggested that ACSS2 regulates activation of the NLRP3 inflammasome and pyroptosis by inducing the KLF5/NF-κB pathway in RTECs. These results identified ACSS2 as a potential therapeutic target in AKI.

MiR-15b-3p weakens bicalutamide sensitivity in prostate cancer via targeting KLF2 to suppress ferroptosis

Bicalutamide (BIC) resistance impedes the treatment of prostate cancer (PCa) and seems to involve ferroptosis; however, the underlying mechanism remains unclear. Our study aimed to explore how miR-15b-3p modulates ferroptosis in response to BIC resistance and determine whether the miRNA is suitable for early screening of PCa. Here, we found that PCa tissues had significantly higher miR-15b-3p expression than adjacent normal tissues. Analysis of blood samples in patients who underwent prostate-specific antigen (PSA) screening revealed that miR-15b-3p was a more accurate diagnostic than PSA (miR-15b-3p area under the curve [AUC] = 0.941, PSA AUC = 0.815). In vitro experiments then demonstrated that miR-15b-3p expression was markedly higher in LNCaP, PC-3, and DU145 cells than in RWPE-1 cells. Treatment with BIC decreased miR-15b-3p expression and progressive ferroptosis. Mechanistically, we identified KLF2 as the downstream target of miR-15b-3p. Overexpressing KLF2 facilitated ferroptosis via augmenting MDA and iron concentrations, in turn inhibiting the SLC7A11/GPX4 axis and decreasing GSH concentration. Through modulating ferroptosis, miR-15b-3p mimic and inhibitor weakened and enhanced BIC sensitivity, respectively. Furthermore, BIC treatment limited xenograft tumor volume in vivo, whereas agomir-15b-3p promoted tumor growth, indicating that miR-15b-3p attenuated the tumor-suppressive effects of BIC. Taken together, our results suggested that miR-15b-3p is crucial to BIC resistance, specifically via targeting KLF2 and thereby suppressing ferroptosis. High miR-15b-3p expression in early PCa screening should reflect a higher probability of cancer. In conclusion, miR-15b-3p has strong potential as a screening and diagnostic biomarker with reliable prospects for clinical application. Furthermore, because patients with high miR-15b-3p and low KLF2 expression have a greater risk of BIC resistance and malignant progression, targeting the miRNA and its downstream protein may be a new treatment strategy.

PRMT5 activates KLF5 by methylation to facilitate lung cancer

The highly expressed oncogenic factor Krüppel-like factor 5 (KLF5) promotes various cancerous processes, such as cell growth, survival, anti-apoptosis, migration and metastasis, particularly in lung cancer. Nevertheless, the modifications to KLF5 after translation are poorly understood. Protein arginine methyltransferase 5 (PRMT5) is considered as an oncogene known to be involved in different types of carcinomas, including lung cancer. Here, we show that the expression levels of PRMT5 and KLF5 are highly expressed lung cancer. Moreover, PRMT5 interacts with KLF5 and facilitates the dimethylation of KLF5 at Arginine 41 in a manner that depends on methyltransferase activity. Downregulation or pharmaceutical suppression of PRMT5 reduces the expression of KLF5 and its downstream targets both in vitro and in vivo. Mechanistically, the dimethylation of KLF5 by PRMT5 promotes the maintenance and proliferation of lung cancer cells at least partially by stabilising KLF5 via regulation of the Akt/GSK3β signalling axis. In summary, PRMT5 methylates KLF5 to prevent its degradation, thereby promoting the maintenance and proliferation of lung cancer cells. These results suggest that targeting PRMT5/KLF5 axis may offer a potential therapeutic strategy for lung cancer.

Integrative ATAC-seq and RNA-seq analysis associated with diabetic nephropathy and identification of novel targets for treatment by dapagliflozin

Dapagliflozin (DAPA) are clinically effective in improving diabetic nephropathy (DN). However, whether and how chromatin accessibility changed by DN responds to DAPA treatment is unclear. Therefore, we performed ATAC-seq, RNA-seq, and weighted gene correlation network analysis to identify the chromatin accessibility, the messenger RNA (mRNA) expression, and the correlation between clinical phenotypes and mRNA expression using kidney from three mouse groups: db/m mice (Controls), db/db mice (case group), and those treated with DAPA (treatment group). RNA-Seq and ATAC-seq conjoint analysis revealed many overlapping pathways and networks suggesting that the transcriptional changes of DN and DAPA intervention largely occured dependently on chromatin remodeling. Specifically, the results showed that some key signal transduction pathways, such as immune dysfunction, glucolipid metabolism, oxidative stress and xenobiotic and endobiotic metabolism, were repeatedly enriched in the analysis of the RNA-seq data alone, as well as combined analysis with ATAC-seq data. Furthermore, we identified some candidate genes (UDP glucuronosyltransferase 1 family, Dock2, Tbc1d10c, etc.) and transcriptional regulators (KLF6 and GFI1) that might be associated with DN and DAPA restoration. These reversed genes and regulators confirmed that pathways related to immune response and metabolism pathways were critically involved in DN progression.

Modulation of Krüppel-like factors (KLFs) interaction with their binding partners in cancers through acetylation and phosphorylation

Post-translational modifications (PTMs) of transcription factors regulate transcriptional activity and play a key role in essentially all biological processes and generate indispensable insight towards biological function including activity state, subcellular localization, protein solubility, protein folding, substrate trafficking, and protein-protein interactions. Amino acids modified chemically via PTMs, function as molecular switches and affect the protein function and characterization and increase the proteome complexity. Krüppel-like transcription factors (KLFs) control essential cellular processes including proliferation, differentiation, migration, programmed cell death and various cancer-relevant processes. We investigated the interactions of KLF group-2 members with their binding partners to assess the role of acetylation and phosphorylation in KLFs on their binding affinity. It was observed that acetylation and phosphorylation at different positions in KLFs have a variable effect on binding with specific partners. KLF2-EP300, KLF4-SP1, KLF6-ATF3, KLF6-JUN, and KLF7-JUN show stabilization upon acetylation or phosphorylation at variable positions. On the other hand, KLF4-CBP, KLF4-EP300, KLF5-CBP, KLF5-WWP1, KLF6-SP1, and KLF7-ATF3 show stabilization or destabilization due to acetylation or phosphorylation at variable positions in KLFs. This provides a molecular explanation of the experimentally observed dual role of KLF group-2 members as a suppressor or activator of cancers in a PTM-dependent manner.

Novel therapeutic targets, including IGFBP3, of umbilical cord mesenchymal stem-cell-conditioned medium in intrauterine adhesion

Mesenchymal stem cells play important roles in repairing injured endometrium. However, the molecular targets and potential mechanism of the endometrial recipient cells for stem cell therapy in intrauterine adhesion (IUA) are poorly understood. In this study, umbilical cord mesenchymal stem-cell-conditioned medium (UCMSCs-CM) produced positive effects on a Transforming growth factor beta (TGF-β) induced IUA cell model. RNA-sequencing was performed on clinical IUA tissues, and the top 40 upregulated and top 20 downregulated mRNAs were selected and verified using high-throughput (HT) qPCR in both tissues and cell models. Based on a bioinformatic analysis of RNA-sequencing and HT-qPCR results, 11 mRNAs were uncovered to be the intervention targets of UCMSCs-CM on IUA endometrium cell models. Among them, IGFBP3 was striking as a key pathogenic gene and a potential diagnostic marker of IUA, which exhibited the area under the curve (AUC), sensitivity, specificity were 0.924, 93.1% and 80.6%, respectively in 60 endometrial tissues. The silencing of IGFBP3 exerted positive effects on the IUA cell model through partially upregulating MMP1 and KLF2. In conclusion, RNA-sequencing combined with HT qPCR based on clinical tissues and IUA cell models were used in IUA research and our results may provide some scientific ideas for the diagnosis and treatment of IUA.

KLF15 transcriptionally activates LINC00689 to inhibit colorectal cancer development

Colorectal cancer is a grievous health concern, we have proved long non-coding RNA LINC00689 is considered as a potential diagnosis biomarker for colorectal cancer, and it is necessary to further investigate its upstream and downstream mechanisms. Here, we show that KLF15, a transcription factor, exhibits the reduced expression in colorectal cancer. KLF15 suppresses the proliferative and metastatic capacities of colorectal cancer cells both in vitro and in vivo by transcriptionally activating LINC00689. Subsequently, LINC00689 recruits PTBP1 protein to enhance the stability of LATS2 mRNA in the cytoplasm. This stabilization causes the suppression of the YAP1/β-catenin pathway and its target downstream genes. Our findings highlight a regulatory network involving KLF15, LINC00689, PTBP1, LATS2, and the YAP1/β-catenin pathway in colorectal cancer, shedding light on potential therapeutic targets for colorectal cancer therapy.

Integrative single-cell characterization of a frugivorous and an insectivorous bat kidney and pancreas

Frugivory evolved multiple times in mammals, including bats. However, the cellular and molecular components driving it remain largely unknown. Here, we use integrative single-cell sequencing (scRNA-seq and scATAC-seq) on insectivorous (Eptesicus fuscus; big brown bat) and frugivorous (Artibeus jamaicensis; Jamaican fruit bat) bat kidneys and pancreases and identify key cell population, gene expression and regulatory differences associated with the Jamaican fruit bat that also relate to human disease, particularly diabetes. We find a decrease in loop of Henle and an increase in collecting duct cells, and differentially active genes and regulatory elements involved in fluid and electrolyte balance in the Jamaican fruit bat kidney. The Jamaican fruit bat pancreas shows an increase in endocrine and a decrease in exocrine cells, and differences in genes and regulatory elements involved in insulin regulation. We also find that these frugivorous bats share several molecular characteristics with human diabetes. Combined, our work provides insights from a frugivorous mammal that could be leveraged for therapeutic purposes.