Forkhead Box K1 Research Articles

Dehydroabietylamine exerts antitumor effects by affecting nucleotide metabolism in gastric cancer.

Nucleotide metabolism is the ultimate and most critical link in the self-replication process of tumors, including gastric cancer (GC). However, in clinical treatment, classic antitumor drugs such as 5-fluorouracil (5-FU) are mostly metabolic analogs of purines or pyrimidines, which lack specificity for tumor cells and therefore have significant side effects. It is unclear whether there are other drugs that can target nucleotide metabolism, except for nucleic acid analogs. Here, we found that a natural compound, dehydroabietylamine (DHAA), significantly reduced the viability and proliferation of GC cells and organoids. DHAA disrupts the purine and pyrimidine metabolism of GC cells, causing DNA damage and further inducing apoptosis. DHAA treatment decreased transcription and protein levels of key enzymes involved in the nucleotide metabolism pathway, with significant reductions in the expression of pyrimidine metabolism key enzymes CAD, DHODH, and purine metabolism key enzymes PAICS. We also found that DHAA directly binds to and reduces the expression of Forkhead box K2 (FOXK2), a common transcription factor for these metabolic enzymes. Ultimately, DHAA was shown to delay tumorigenesis in K19-Wnt1/C2mE transgenic mice model and reduce levels of CAD, DHODH, and PAICS in vivo. We demonstrate that DHAA exerts an anticancer effect on GC by targeting transcription factor FOXK2, reducing transcription of key genes for nucleotide metabolism and impairing nucleotide biosynthesis, thus DHAA is a promising candidate for GC therapy.

Identification of differentially methylated regions associated with both liver fibrosis and hepatocellular carcinoma

BackgroundLiver fibrosis is a major risk factor for hepatocellular carcinoma (HCC). We have previously reported that differentially methylated regions (DMRs) are correlated with the fibrosis stages of metabolic dysfunction-associated steatotic liver disease (MASLD). In this study, the methylation levels of those DMRs in liver fibrosis and subsequent HCC were examined.MethodsThe methylation levels of DMRs were investigated using alcoholic cirrhosis and HCC (GSE60753). The data of hepatitis C virus-infected cirrhosis and HCC (GSE60753), and two datasets (GSE56588 and GSE89852) were used for replication analyses. The transcriptional analyses were performed using GSE114564, GSE94660, and GSE142530.ResultsHypomethylated DMR and increased transcriptional level of zinc finger and BTB domain containing 38 (ZBTB38) were observed in HCC. Hypermethylated DMRs, and increased transcriptional levels of forkhead box K1 (FOXK1) and zinc finger CCCH-type containing 3 (ZC3H3) were observed in HCC. The methylation levels of DMR of kazrin, periplakin interacting protein (KAZN) and its expression levels were gradually decreased as cirrhosis progressed to HCC.ConclusionsChanges in the methylation and transcriptional levels of ZBTB38, ZC3H3, FOXK1, and KAZN are important for the development of fibrosis and HCC; and are therefore potential therapeutic targets and diagnostic tools for cirrhosis and HCC.

Circ-ATAD1 as Competing Endogenous RNA for miR-191-5p Forces Non-small Cell Lung Cancer Progression.

The association of circular RNAs (circRNAs) with non-small cell lung cancer (NSCLC) has been recognized extensively. In view of this, our study particularly surveyed the underlying mechanism of circ-ATAD1 in the disease. First, an analysis of the clinical expression of circ-ATPase family AAA domain containing 1 (ATAD1) was performed, followed by further evaluation of the relationship between circ-ATAD1 expression and prognosis. Then, A549 cells were treated with single transfection or combined transfection with the plasmid vectors that interfere with circ-ATAD1 or miR-191-5p. circ-ATAD1 and miR-191-5p levels were detected by reverse transcription quantitative polymerase chain reaction to verify the transfection success. Then, cell proliferation was checked by cell count kit-8 and clonal formation test. Cell apoptosis was analyzed by flow cytometry. Cell migration and invasion were examined by wound healing assay and Transwell. Finally, the targeting of miR-191-5p to circ-ATAD1 or Forkhead Box K1 (FOXK1) was verified by bioinformation website starBase analysis and dual-luciferase reporter assay. circ-ATAD1 was expressed abundantly in tumor tissues of NSCLC patients and had a predictive value in poor prognosis. circ-ATAD1 underexpression or miR-191-5p overexpression could obstruct A549 cells to behave aggressively, while circ-ATAD1 upregulation or miR-191-5p depletion resulted in the promotion of aggressiveness of A549 cells. Interestingly, circ-ATAD1 could decoy miR-191-5p. miR-191-5p negatively regulated FOXK1 expression, and downregulating miR-191-5p or upregulating FOXK1 rescued circ-ATAD1 downregulation-mediated influences on NSCLC cells. circ-ATAD1 accelerates NSCLC progression by absorbing miR-191-5p to upregulate FOXK1 expression.

Foxk1 stimulates adipogenic differentiation via a peroxisome proliferator-activated receptor gamma 2-dependent mechanism.

Adipogenesis is a tightly regulated process, and its dysfunction has been linked to metabolic disorders such as obesity. Forkhead box k1 (Foxk1) is known to play a role in the differentiation of myogenic precursor cells and tumorigenesis of different types of cancers; however, it is not clear whether and how it influences adipocyte differentiation. Here, we found that Foxk1 was induced in mouse primary bone marrow stromal cells (BMSCs) and established mesenchymal progenitor/stromal cell lines C3H/10T1/2 and ST2 after adipogenic treatment. In addition, obese db/db mice have higher Foxk1 expression in inguinal white adipose tissue than nonobese db/m mice. Foxk1 overexpression promoted adipogenic differentiation of C3H/10T1/2, ST2 cells and BMSCs, along with the enhanced expression of CCAAT/enhancer binding protein-α, peroxisome proliferator-activated receptor γ (Pparγ), and fatty acid binding protein 4. Moreover, Foxk1 overexpression enhanced the expression levels of lipogenic factors during adipogenic differentiation in both C3H/10T1/2 cells and BMSCs. Conversely, Foxk1 silencing impaired these cells from fully differentiating. Furthermore, adipogenic stimulation induced the nuclear translocation of Foxk1, which depended on the mTOR and PI3-kinase signaling pathways. Subsequently, Foxk1 is directly bound to the Pparγ2 promoter, stimulating its transcriptional activity and promoting adipocyte differentiation. Collectively, our study provides the first evidence that Foxk1 promotes adipocyte differentiation from progenitor cells by promoting nuclear translocation and upregulating the transcriptional activity of the Pparγ2 promoter during adipogenic differentiation.

FOXK1 upregulation is correlated with tumor progression and tumor associated macrophages infiltration in renal cell carcinoma.

Renal cell carcinoma (RCC)is one of the most common urological cancers in adults. Forkhead box k1 (FOXK1)is a transcription factor involved in the progression of various malignant tumors. In this study, we aimed to investigate the expression and roles of FOXK1 in RCC development. Our findings revealed increased expression of FOXK1 in RCC tumor tissues and cell lines compared with normal controls. Functional assays demonstrated that knockdown of FOXK1 significantly inhibited proliferation, migration, invasion, and promoted apoptosis in RCC cells. Furthermore, FOXK1 knockdown suppressed epithelial-mesenchymal transition and Wnt signaling in RCC cells. Additionally, we observed a correlation between FOXK1 upregulation and tumor associated macrophages infiltration in RCC. These results suggest that FOXK1 acts as an oncogene in RCC and may serve as a potential therapeutic target for RCC treatment.

CangFu Daotan decoction improves polycystic ovarian syndrome by downregulating FOXK1

Objective: Polycystic ovarian syndrome (PCOS) is a prevalent gynecologic disorder, often associated with abnormal follicular development. Cangfu Daotan decoction (CFD) is a traditional Chinese medicine formula that is effective in alleviating PCOS clinically, but the specific mechanism remains unclear. Forkhead box K1 (FOXK1) is associated with cellular function. This study aimed to explore the effects of CFD and FOXK1 on PCOS.Methods: High-fat diet and letrozole were combined to establish PCOS rat models. Next, primary GCs were extracted from those PCOS rats. Then, GC cells were transfected with si-FOXK1 or oe-FOXK1. CFD-contain serum was prepared, and experiments were conducted to investigate the regulation of FOXK1 by CFD.Results: FOXK1 was highly expressed in GCs of PCOS rats. Further investigation revealed that FOXK1 overexpression resulted in inhibition of proliferation and DNA synthesis, along with promotion of apoptosis and autophagy in GCs. Additionally, it was found that FOXK1 promoted the expressions of the AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway-related proteins. Interestingly, treatment with CFD reversed all the effects of FOXK1 overexpression in GCs. Conclusion: This study demonstrated that CFD exerted a protective role in PCOS by inhibiting FOXK1, which provided a research basis for the application of CFD in PCOS, and suggested that FOXK1 is a novel therapeutic target in PCOS treatment.

FOXK2 regulates PFKFB3 in promoting glycolysis and tumorigenesis in multiple myeloma

Forkhead box K2 (FOXK2) is a transcription factor involved in regulating the pathophysiological processes in many types of cancers. Functioning as either an oncogene or tumor suppressor, FOXK2 is involved in cell proliferation, metastasis, DNA damage, metabolism, and autophagy. However, the functions of FOXK2 in multiple myeloma (MM) are still unexplored. Here we show that FOXK2 silencing by small interfering RNA (siRNA) prevented the expression of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) via dephosphorylation of an AMP-activated protein kinase (AMPK). Consistently, suppression of FOXK2 inhibited glycolysis and cell proliferation in MM cells. Furthermore, the correlation between FOXK2 expression and disease progression in MM was evaluated using the TCGA (The Cancer Genome Atlas) database. Taken together, we identified a novel FOXK2-dependent signaling pathway involved in the regulation of PFKFB3 expression in response to glycolysis, which might serve as a potential therapeutic target in MM.

FOXK1 promotes nonalcoholic fatty liver disease by mediating mTORC1-dependent inhibition of hepatic fatty acid oxidation

Nonalcoholic fatty liver disease (NAFLD) is a chronic metabolic disorder caused by overnutrition and can lead to nonalcoholic steatohepatitis (NASH) and hepatocellular carcinoma (HCC). The transcription factor Forkhead box K1 (FOXK1) is implicated in regulation of lipid metabolism downstream of mechanistic target of rapamycin complex 1 (mTORC1), but its role in NAFLD-NASH pathogenesis is understudied. Here, we show that FOXK1 mediates nutrient-dependent suppression of lipid catabolism in the liver. Hepatocyte-specific deletion of Foxk1 in mice fed a NASH-inducing diet ameliorates not only hepatic steatosis but also associated inflammation, fibrosis, and tumorigenesis, resulting in improved survival. Genome-wide transcriptomic and chromatin immunoprecipitation analyses identify several lipid metabolism-related genes, including Ppara, as direct targets of FOXK1 in the liver. Our results suggest that FOXK1 plays a key role in the regulation of hepatic lipid metabolism and that its inhibition is a promising therapeutic strategy for NAFLD-NASH, as well as for HCC.

MiR-144-3p represses hepatocellular carcinoma progression by affecting cell aerobic glycolysis via FOXK1.

Aerobic glycolysis is a unique mark of cancer cells, which enables therapeutic intervention in cancer. Forkhead box K1 (FOXK1) is a transcription factor that facilitates the progression of multiple cancers including hepatocellular carcinoma (HCC). Nevertheless, it is unclear whether or not FOXK1 can affect HCC cell glycolysis. This study attempted to study the effect of FOXK1 on HCC cell glycolysis. Expression of mature miRNAs and mRNAs, as well as clinical data, was downloaded from The Cancer Genome Atlas-Liver hepatocellular carcinoma (TCGA-LIHC) dataset. FOXK1 and miR-144-3p levels were assessed through quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Targeting of the relationship between miR-144-3p and FOXK1 was verified via a dual-luciferase assay. Pathway enrichment analysis of FOXK1 was performed by Gene Set Enrichment Analysis (GSEA). Cell function assays revealed the glycolytic ability, cell viability, migration, invasion, cell cycle, and apoptosis of HCC cells in each treatment group. Bioinformatics analysis suggested that FOXK1 was upregulated in tissues of HCC patients, while the upstream miR-144-3p was downregulated in tumour tissues. Dual-luciferase assay implied a targeting relationship between miR-144-3p and FOXK1. Cellular experiments implied that silencing FOXK1 repressed HCC cell glycolysis, which in turn inhibited the HCC malignant progression. Rescue assay confirmed that miR-144-3p repressed glycolysis in HCC cells by targeting FOXK1, and then repressed HCC malignant progression. miR-144-3p/FOXK1 axis repressed malignant progression of HCC via affecting the aerobic glycolytic process of HCC cells. miR-144-3p and FOXK1 have the potential to become new therapeutic targets for HCC, which provide new insights for HCC treatment.

FOXK2 transcription factor and its roles in tumorigenesis (Review).

Forkhead box K2 (FOXK2) is a central transcriptional regulator of embryonic development and cell homeostasis. Since its discovery, evidence has shown that FOXK2 mediates a variety of biological processes involving in genomic stability, DNA repair, cancer stem cell maintenance, cell proliferation, apoptosis and cell metabolism. The inherent structural characteristics of FOXK2 enable it as a transcriptional factor (TF) to cooperate with other active molecules in cancer development. FOXK2 mediates several significant chromatin events that are necessary for some chromatin accessibility and protein-protein interaction. FOXK2 is involved in the pathogenesis of a number of types of cancer as an oncoprotein or tumor suppressor depending on its interactive partners. Therefore, the loss of FOXK2 and its functions directly or indirectly affect the fate of cells. FOXK2 expresses differentially in a number of types of cancer and is involved in a number of aspects of carcinogenesis. However, its roles in tumorigenesis remain largely unexplored. The present review focused on the latest findings and evidence on the broad roles and possible mediating mechanisms of FOXK2 in carcinogenesis. The recent findings about FOXK2 may shed light on the direction of future FOXK2 research in tumorigenesis.

Regulation and roles of FOXK2 in cancer.

Forkhead box K2 (FOXK2) is a member of the forkhead box transcription factor family that contains an evolutionarily conserved winged-helix DNA-binding domain. Recently, an increasing number of studies have demonstrated that FOXK2 plays an important role in the transcriptional regulation of cancer. Here, we provide an overview of the mechanisms underlying the regulation of FOXK2 expression and function and discuss the roles of FOXK2 in tumor pathogenesis. Additionally, we evaluated the prognostic value of FOXK2 expression in patients with various cancers. This review presents an overview of the different roles of FOXK2 in tumorigenesis and will help inform the design of experimental studies involving FOXK2. Ultimately, the information presented here will help enhance the therapeutic potential of FOXK2 as a cancer target.

MicroRNA-16-5p suppresses cell proliferation and angiogenesis in colorectal cancer by negatively regulating forkhead box K1 to block the PI3K/Akt/mTOR pathway.

MicroRNAs (miRNAs/miRs) have aroused increasing attention in colorectal cancer (CRC) therapy. This study is designed for a detailed analysis of the roles of miR-16-5p and forkhead box K1 (FOXK1) in cell angiogenesis and proliferation during CRC in addition to their underlying mechanisms. CRC tissues and colon cancer cell lines (SW620 and HCT8) were investigated. qRT-PCR and Western blot were utilized to evaluate miR-16-5p and FOXK1 expression. Following gain- and loss-of-function assays on miR-16-5p or FOXK1, the effects of miR-16-5p and FOXK1 were assessed on cell angiogenesis and proliferation in CRC cells. A dual-luciferase reporter assay was employed to evaluate the binding relationship of miR-16-5p and FOXK1. Western blot was used to determine the effects of miR-16-5p and FOXK1 on key molecules of the PI3K/Akt/mTOR pathway. Highly expressed FOXK1 and lowly expressed miR-16-5p were observed in CRC cells and tissues. miR-16-5p overexpression or FOXK1 knockdown reduced CRC cell proliferation and angiogenesis of human umbilical vein endothelial cells co-cultured with the supernatant of CRC cells, whereas miR-16-5p silencing or FOXK1 upregulation caused opposite trends. Additionally, miR-16-5p negatively modulated FOXK1 expression. The blockade of the PI3K/Akt/mTOR pathway was triggered by miR-16-5p overexpression or FOXK1 silencing. In conclusion, miR-16-5p hampers cell angiogenesis and proliferation during CRC by targeting FOXK1 to block the PI3K/Akt/mTOR pathway.

ATF3 -activated accelerating effect of LINC00941/lncIAPF on fibroblast-to-myofibroblast differentiation by blocking autophagy depending on ELAVL1/HuR in pulmonary fibrosis

ABSTRACT Idiopathic pulmonary fibrosis (IPF) is characterized by lung scarring and has no effective treatment. Fibroblast-to-myofibroblast differentiation and myofibroblast proliferation and migration are major clinical manifestations of this disease; hence, blocking these processes is a practical treatment strategy. Here, highly upregulated LINC00941/lncIAPF was found to accelerate pulmonary fibrosis by promoting fibroblast-to-myofibroblast differentiation and myofibroblast proliferation and migration. Assay for transposase-accessible chromatin using sequencing and chromatin immunoprecipitation experiments elucidated that histone 3 lysine 27 acetylation (H3K27ac) activated the chromosome region opening in the LINC00941 promoter. As a consequence, the transcription factor ATF3 (activating transcription factor 3) bound to this region, and LINC00941 transcription was enhanced. RNA affinity isolation, RNA immunoprecipitation (RIP), RNase-RIP, half-life analysis, and ubiquitination experiments unveiled that LINC00941 formed a RNA-protein complex with ELAVL1/HuR (ELAV like RNA binding protein 1) to exert its pro-fibrotic function. Dual-fluorescence mRFP-GFP-MAP1LC3/LC3 (microtubule associated protein 1 light chain 3) adenovirus monitoring technology, human autophagy RT2 profiler PCR array, and autophagic flux revealed that the LINC00941-ELAVL1 axis inhibited autophagosome fusion with a lysosome. ELAVL1 RIP-seq, RIP-PCR, mRNA stability, and rescue experiments showed that the LINC00941-ELAVL1 complex inhibited autophagy by controlling the stability of the target genes EZH2 (enhancer of zeste 2 polycomb repressive complex 2 subunit), STAT1 (signal transducer and activators of transcription 1) and FOXK1 (forkhead box K1). Finally, the therapeutic effect of LINC00941 was confirmed in a mouse model and patients with IPF. This work provides a therapeutic target and a new effective therapeutic strategy related to autophagy for IPF. Abbreviations: ACTA2/a-SMA: actin alpha 2, smooth muscle; ATF3: activating transcription factor 3; ATG: autophagy related; Baf-A1: bafilomycin A1; BLM: bleomycin; CDKN: cyclin dependent kinase inhibitor; CLN3: CLN3 lysosomal/endosomal transmembrane protein, battenin; COL1A: collagen type I alpha; COL3A: collagen type III alpha; CXCR4: C-X-C motif chemokine receptor 4; DRAM2: DNA damage regulated autophagy modulator 2; ELAVL1/HuR: ELAV like RNA binding protein 1; EZH2: enhancer of zeste 2 polycomb repressive complex 2 subunit; FADD: Fas associated via death domain; FAP/FAPα: fibroblast activation protein alpha; FOXK1: forkhead box K1; FVC: forced vital capacity; GABARAP: GABA type A receptor-associated protein; GABARAPL2: GABA type A receptor associated protein like 2; IGF1: insulin like growth factor 1; IPF: idiopathic pulmonary fibrosis; LAMP: lysosomal associated membrane protein; lncRNA: long noncoding RNA; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; NPC1: NPC intracellular cholesterol transporter 1; RGS: regulator of G protein signaling; RPLP0: ribosomal protein lateral stalk subunit P0; ROC: receiver operating characteristic; S100A4: S100 calcium binding protein A4; SQSTM1/p62: sequestosome 1; STAT1: signal transducers and activators of transcription 1; TGFB1/TGF-β1: transforming growth factor beta 1; TNF: tumor necrosis factor; UIP: usual interstitial pneumonia; ULK1: unc-51 like autophagy activating kinase 1; VIM: vimentin.

CircFOXK2 enhances tumorigenesis and immune evasion in non-small cell lung cancer by miR-485-5p/PD-L1 axis.

Circular RNAs (circRNAs) serve a key role in lots of cancers. The outcomes of upregulated circular RNA forkhead box K2 (circFOXK2) on non-small cell lung cancer (NSCLC) persisted uncertainly. In this study, the role of circFOXK2 in NSCLC was inspected. The abundances of circFOXK2, microRNA-485-5p (miR-485-5p) and programmed cell death ligand-1 (PD-L1) were confirmed by quantitative real-time PCR and western blot. Cell counting kit-8 (CCK-8) assay and clonogenic assay were accomplished to conclude the proliferation of NSCLC cells. Wound healing and transwell assays were implemented to evaluate cell migration and invasion. Lactate dehydrogenase (LDH) cytotoxicity assay was enforced to quantify the cytotoxicity of CD8+ T cells. Flow cytometry assay was employed to detect apoptosis. Besides, the mice experiments were utilized for in vivo tumorigenesis analysis. Dual-luciferase reporter assay was carried out to reveal the associations between miR-485-5p and circFOXK2 or PD-L1. CircFOXK2 and PD-L1 levels were augmented in NSCLC. CircFOXK2 targeted miR-485-5p, which could bind to PD-L1. CircFOXK2 served a key role in NSCLC tumorigenesis and cytotoxicity of CD8+ T cells. MiR-485-5p inhibition or PD-L1 overexpression abolished the inhibitory effects of circFOXK2 lack on NSCLC tumorigenesis and cytotoxicity of CD8+ T cells. CircFOXK2 sponged miR-485-5p to stimulate PD-L1 and expedited NSCLC development.

Circular RNA Eps15-homology domain containing protein 2 motivates proliferation, glycolysis but refrains autophagy in non-small cell lung cancer via crosstalk with microRNA-3186-3p and forkhead box K1

ABSTRACT Numerous studies have clarified the involvement of circular RNAs (circRNAs) in modulating malignant behavior of non-small cell lung cancer (NSCLC), while the concrete mechanism is not completely elucidated. The aim of the study was to figure out the latent functions and molecular mechanisms of circRNA Eps15-homology domain containing protein 2 (EHD2) on NSCLC proliferation, glycolysis and autophagy. The results clarified in NSCLC elevated expression of circEHD2 and declined expression of microRNA (miR)-3186-3p. Repressive circEHD2 or enhancive miR-3186-3p facilitated cell apoptosis rate and autophagy substrates LC3BII and Beclin-1, but curbed the colony-formation and DNA replication ability of NSCLC, glucose consumption, lactic acid production, glycolytic rate-limiting enzyme HK-2 and glutamine hydrolase GLS1 and P62, while overexpressed circEHD2 was adverse. Meanwhile, the impacts of repressive and elevated circEHD2 on NSCLC were turned around via reduced miR-3186-3p or forkhead box k1 (FOXK1) separately. Mechanically, FOXK1 was augmented via circEHD2ʹs competitive integration of miR-3186-3p. Depressive circEHD2 refrained NSCLC tumor growth, which was accelerated via enhancive one. All in all, circEHD2 accelerates the proliferation and glycolysis of NSCLC, but refrains autophagy and apoptosis via strengthening FOXK1 via the adsorption of miR-3186-3p, which is supposed to be a latent molecular target for NSCLC therapy later.

Long noncoding RNASEH1-AS1 exacerbates the progression of non-small cell lung cancer by acting as a ceRNA to regulate microRNA-516a-5p/FOXK1 and thereby activating the Wnt/β-catenin signaling pathway.

BackgroundTill now, no study has focused on the functions of RNASEH1 antisense RNA 1 (RNASEH1‐AS1) in non‐small cell lung cancer (NSCLC). Accordingly, we measured the expression of RNASEH1‐AS1 in NSCLC and characterized its functions in detail. Finally, our research elucidated the mechanisms that occurred downstream of RNASEH1‐AS1.MethodsRNASEH1‐AS1 expression was examined utilizing TCGA database and qRT‐PCR. Functional experiments were conducted to study the tumor‐associated functions of RNASEH1‐AS1. The targeting relationship among RNASEH1‐AS1, microRNA‐516a‐5p (miR‐516a‐5p), and forkhead box K1 (FOXK1) was revealed utilizing RNA immunoprecipitation and luciferase reporter assays.ResultsUtilizing TCGA database and our own cohort, we found a significantly increased level of RNASEH1‐AS1 in NSCLC. The high level of RNASEH1‐AS1 was markedly related with poor clinical outcomes. Knockdown of RNASEH1‐AS1 expression inhibited NSCLC cell growth, metastatic capacities, and epithelial‐mesenchymal transition and promoted the apoptosis in vitro, whereas RNASEH1‐AS1 overexpression exerted the opposite effects. Additionally, knocking down RNASEH1‐AS1 expression suppressed tumor growth in vivo. RNASEH1‐AS1 was confirmed to act as a miR‐516a‐5p sponge, consequently upregulating FOXK1 expression in NSCLC cells. As revealed by the subsequent rescue experiments, the miR‐516a‐5p/FOXK1 axis served as a downstream effector of RNASEH1‐AS1. In addition, by controlling the miR‐516a‐5p/FOXK1 axis, RNASEH1‐AS1 was capable of activating the Wnt/β‐catenin pathway.ConclusionRNASEH1‐AS1 exacerbated the oncogenicity of NSCLC by affecting the miR‐516a‐5p/FOXK1 axis and consequently promoting the activation of Wnt/β‐catenin pathway. Our newly identified RNASEH1‐AS1/miR‐516a‐5p/FOXK1/Wnt/β‐catenin network may offer an interesting foundation for NSCLC treatment in the clinic.

Repression of lncRNA PART1 attenuates ovarian cancer cell viability, migration and invasion through the miR-503-5p/FOXK1 axis

BackgroundOvarian cancer (OC) is a female malignant tumor with a high fatality rate. Long non-coding RNAs (lncRNAs) are deeply involved in OC progression. The aim of this study is to explore the specific mechanism of lncRNA prostate androgen-regulated transcript 1 (PART1) in OC.MethodsQuantitative real time PCR was utilized to determine the expression levels of PART1, microRNA (miR)-503-5p and forkhead-box k1 (FOXK1) in OC tissues and/or cells. The cell viability, migration, and invasion in OC were evaluated by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-h-tetrazolium bromide assay, wound healing assay and transwell invasion assay, respectively. Flow cytometry was used to analyze the cell apoptosis. The xenograft tumor was conducted in nude mice to verify the effect of PART1 knockdown on OC in vivo. The target relationships among PART1, miR-503-5p and FOXK1 were predicted by StarBase, and verified by luciferase reporter assay. The level of FOXK1 was assessed by western blot.ResultsIncreased expression of PART1 and FOXK1 was observed in OC tissues or cells, whereas miR-503-5p was downregulated. PART1 silencing or miR-503-5p overexpression repressed the cell viability, migration and invasion, and protomed apoptosis. Meanwhile, miR-503-5p was a target of PART1, and FOXK1 was a direct target gene of miR-503-5p. Both downregulation of miR-503-5p and upregulation of FOXK1 partly relieved the suppressive effects of PART1 knockdown on the oncogenicity of OC in vitro.ConclusionDecreased PART1 represses the cell viability, migration and invasion of OC via regulating the miR-503-5p/FOXK1 axis, which provided an underlying target for treating OC.

Long non-coding RNA tumor protein 53 target gene 1 promotes cervical cancer development via regulating microRNA-33a-5p to target forkhead box K2

ABSTRACT Long non-coding RNA tumor protein 53 target gene 1 (TP53TG1) has been unraveled to exert regulatory effects on cancer progression, while the regulatory function of TP53TG1 on cervical cancer (CC) via regulating microRNA (miR)-33a-5p/Forkhead box K2 (FOXK2) axis remains rarely explored. This study aims to unearth the regulatory mechanism of TP53TG1/miR-33a-5p/FOXK2 axis in CC. The CC clinical samples were collected, and CC cells were cultured. TP53TG1, miR-33a-5p and FOXK2 levels were examined in CC tissues and cells. The CC cells were transfected with high- or low-expressed TP53TG1, FOXK2 or miR-33a-5p to determine the changes of CC cell biological activities and the status of phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. The tumorigenesis in nude mice was conducted. The relationship among TP53TG1, miR-33a-5p and FOXK2 was validated. TP53TG1 and FOXK2 expression levels were increased and miR-33a-5p expression level was reduced in CC cells and tissues. The silenced TP53TG1 or FOXK2, or elevated miR-33a-5p decelerated the CC cell development and restrained the activation of PI3K/AKT/mTOR signaling pathway. The depleted FOXK2 or elevated miR-33a-5p reversed the effects of decreased TP53TG1 on CC cell progression. TP53TG1 sponged miR-33a-5p, which targeted FOXK2. The experiment in vivo validated the outcomes of the experiment in vitro. TP53TG1 accelerates the CC development via regulating miR-33a-5p to target FOXK2 with the involvement of PI3K/AKT/mTOR signaling pathway. This study provides novel theory basis and distinct therapeutic targets for CC treatment.

Senescence Connects Autophagy Deficiency to Inflammation and Tumor Progression in the Liver.

Background & AimsCellular senescence frequently is present in injured livers. The induction mechanism and the pathologic role are not always clear. We aimed to understand the dynamics of senescence induction and progression, and the mechanism responsible for the pathology using a mouse model that disables the essential process of autophagy.MethodsMice deficient in key autophagy genes Atg7 or Atg5 in the liver were used. Senescence was measured using established cellular and molecular signatures. The mechanistic roles of nuclear factor erythroid 2 (NRF2), forkhead box K1, and C-C motif chemokine receptor 2 (CCR2) were assessed using mouse genetic models. Liver functions, pathology, and tumor development were measured using biochemical and histologic approaches.ResultsInducible deletion of Atg7 rapidly up-regulated cyclin-dependent kinase inhibitors independently of injury and induced senescence-associated β-galactosidase activities and senescence-associated secretory phenotype (SASP). Sustained activation of NRF2 was the major factor causing senescence by mediating oxidative DNA damage and up-regulating C-C motif chemokine ligand 2, a key component of autophagy-related SASP, via the NRF2–forkhead box K1 axis. Senescence was responsible for hepatic inflammation through CCR2-mediated recruitment of CD11b+ monocytes and CD3+ T cells. The CCR2-mediated process in turn enhanced senescence and SASP by up-regulating cyclin-dependent kinase inhibitors and chemokines. Thus, senescence and inflammation can mutually augment each other, forming an amplification loop for both events. The CCR2-mediated process also modulated liver injury and tumor progression at the later stage of autophagy deficiency–related pathology.ConclusionsThese results provide the insight that hepatic senescence can occur early in the disease process, triggers inflammation and is enhanced by inflammation, and has long-term effects on liver injury and tumor progression.

Histone deacetylase 3 contributes to the antiviral innate immunity of macrophages by interacting with FOXK1 to regulate STAT1/2 transcription.

It is well known that interferon (IFN)-α/-β activates the JAK/STAT signaling pathway and suppresses viral replication through the induction of IFN stimulated genes (ISGs). Here, we report that knockout of HDAC3 from macrophages results in the decreased expression of STAT1 and STAT2, leading to defective antiviral immunity in cells and mice. Further studies show that HDAC3 interacts with a conserved transcription factor Forkhead Box K1 (FOXK1), co-localizes with FOXK1 at the promoter of STAT1 and STAT2, and is required for protecting FOXK1 from lysosomal system-mediated degradation. FOXK1-deficient macrophages also show low STAT1 and STAT2 expression with defective responses to viruses. Thus, our studies uncover the biological importance of HDAC3 in regulating the antiviral immunity of macrophages through interacting with FOXK1 to regulate the expression of STAT1 and STAT2.