The purpose of the present study was to investigate the underlying molecular mechanism of hepatocellular carcinoma (HCC) using bioinformatics approaches. The microarray dataset GSE64041 was downloaded from the Gene Expression Omnibus database, which included 60 tumor liver samples and 60 matched control samples. Differentially expressed genes (DEGs) between HCC and control groups were identified. Then functional enrichment analyses, protein‑protein interaction (PPI) network, sub‑network and integrated transcription factor (TF)‑microRNA (miRNA)‑target network analyses were performed for these DEGs. A total of 378 DEGs were obtained, including 101 upregulated and 277 downregulated DEGs. In addition, functional enrichment analysis for DEGs in the sub‑network revealed 'cell division' and 'cell cycle' as key Gene Ontology (GO) terms and pathways. Topoisomerase (DNA) IIα (TOP2A) and integrin subunit α2 (ITGA2) were hub nodes in the PPI network. TOP2A, cyclin dependent kinase 1 (CDK1) and polo like kinase 1 (PLK1) were revealed to be hub nodes in the sub‑network. Finally, 4 TFs including forkhead box M1 (FOXM1), E2F transcription factor 4 (E2F4), SIN3 transcription regulator family member A (SIN3A) and transcription factor 7 like 1 (TCF7L1) were obtained through integrated network analysis. TOP2A, ITGA2, PLK1 and CDK1 may be key genes involved in HCC development. 'Cell division' and 'cell cycle' were indicated to act as key GO terms and Kyoto Encyclopedia of Genes and Genomes pathways in HCC. In addition, FOXM1, TCF7L1, E2F4 and SIN3A were revealed to be key TFs associated with HCC.

Nasopharyngeal carcinoma (NPC) is a highly invasive malignancy with cervical lymphopathy as the initial presentation. Epithelial‑mesenchymal transition (EMT), a process by which epithelial cells lose cell‑cell adhesion and gain migratory and invasive properties, has a pivotal role in metastasis. Forkhead box C1 (FoxC1), a member of the forkhead family of transcription factors, induces EMT and has a critical role in metastasis of multiple human cancers. However, the role of FoxC1 in the progression of NPC has remained elusive. The present study revealed that the expression of FoxC1 was markedly elevated in NPC tissues compared with that in chronically inflamed nasopharyngeal tissues and was closely correlated with vimentin, fibronectin and N‑cadherin expression as indicated by immunohistochemical assays. In addition, high FoxC1 expression was positively associated with lymph node metastasis, distant metastasis and an advanced clinical stage in patients with NPC. Furthermore, FoxC1 expression was high in NPC cell lines while being low in an immortalized normal nasopharyngeal epithelial cell line. In vitro, knockdown of FoxC1 in the CNE2 human NPC cell line by small interfering RNA downregulated vimentin, fibronectin and N‑cadherin expression and reduced the migratory and invasive capacity of CNE2 cells. In conclusion, the present study indicated that FoxC1 has a pivotal role in EMT through the upregulation of vimentin, fibronectin and N‑cadherin expression. Thus, FoxC1 may be a potential therapeutic target in NPC.

3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosyl-cycloastragenol, or Astragaloside IV (AST), is one of the major active ingredients isolated from Astragalus membranaceous with distinct pharmacological effects, and possesses anti-inflammatory, immunoregulatory and antifibrotic properties. However, the effects of AST on allergic rhinitis remain to be elucidated. The present study aimed to examine the effects of AST on immunoglobulin (Ig) E‑mediated allergic reactions in vivo, by using a mouse model of allergic rhinitis established via repetitive sensitization and intranasal challenge with ovalbumin (OVA). Intragastric administration of AST (25 mg/kg or 50 mg/kg) or dexamethasone (DEX; 3 mg/kg) significantly alleviated the inflammatory response, nasal symptoms and mucosa remodeling, and decreased the serum levels of OVA‑specific IgE in allergic mice. Furthermore, treatment with AST or DEX significantly suppressed the mRNA and protein expression levels of the transcription factor GATA‑3 and retinoic acid receptor‑related orphan nuclear receptor (ROR)γt in tissue samples isolated from the spleen and nasal mucosa of mice with allergic rhinitis. Conversely, mRNA and protein expression levels of T‑box protein expressed in T cells (T‑bet) and forkhead box protein 3 (Foxp3) were upregulated in the spleen and nasal mucosa of mice with allergic rhinitis following treatment with AST or DEX, and spleen protein levels of signal transducer and activator of transcription 3 followed a similar trend. In addition, treatment with AST was associated with fewer adverse events compared with treatment with DEX. The present results suggested that treatment with AST may attenuate OVA‑induced allergic rhinitis via regulating the expression of the transcription factors GATA‑3, RORγt, T‑bet and Foxp3, which commit T helper cells to the Th1 phenotype. Therefore, AST may represent an alternative therapeutic approach for the treatment of patients with allergic rhinitis.

Hilar cholangiocarcinoma (HC) has a poor outcome in terms of survival. Forkhead box K1 (FOXK1) dysregulation is critical in solid tumors, which serves a pivotal role in the biological characteristics, such as invasion and migration, but its expression and functions in HC are unclear. The present study investigated the clinical significance and biological functions of FOXK1 in HC. Tumor microarrays and immunohistochemistry were used to evaluate FOXK1 in HC and its expression was modulated to determine its effects on chemoresistance and tumorigenesis. FOXK1 was highly expressed in HC and cell lines, which was associated with tumor invasion, regional lymph node metastasis, tumor recurrence and poor prognosis. Silencing FOXK1 in HC cells inhibited invasion and migration, upregulated E-cadherin, and downregulated vimentin, matrix metallopeptidase 9 and Twist in HC cells. Sensitivity to 5-fluorouracil and cisplatin was increased, and glutathione S-transferase π, multidrug resistance mutation 1 and P-glycoprotein expression levels were downregulated in RBE cells in vitro following FOXK1 knockdown. These results indicated that FOXK1 plays an oncogenic role in HC progression and can serve as a novel therapeutic target for HC.

Forkhead box (FOX) proteins are multifaceted transcription factors that have been shown to be involved in cell cycle progression, proliferation and metastasis. FOXP4, a member of the FOX family, has been implicated in diverse biological processes in tumor initiation and progression. However, the molecular mechanisms of FOXP4 in laryngeal squamous cell carcinoma (LSCC) remain unknown. In the present study, differentially expressed transcripts in transforming growth factor‑β‑treated TU177 cells were screened using microarrays and it was found that FOXP4 was significantly upregulated. The high expression of FOXP4 was detected in LSCC tissues and cells, and predicted poor prognosis. The role of FOXP4 in laryngeal cancer cell proliferation, migration and invasion was determined by gain‑ and loss‑of‑function assays. Besides, FOXP4 was demonstrated to participate in the epithelial‑mesenchymal transition process at the mRNA and protein levels. Mechanically, FOXP4 directly bound to the promoter of lymphoid enhancer‑binding factor 1 and activated Wnt signaling pathway, which was confirmed via chromatin immunoprecipitation and luciferase reporter assays. Consequently, these findings provided novel mechanisms of FOXP4 in LSCC progression, which may be considered as potential therapeutic and prognostic targets for LSCC.

The aim of the present study was to establish an integrated network of DNA methylation and RNA expression in an ovalbumin (OVA)‑induced asthma model, and to investigate the epigenetically‑regulated genes involved in asthma development. Genome‑wide CpG‑DNA methylation profiling was conducted through the use of a methylated DNA immunoprecipitation microarray and RNA sequencing was performed using three lung samples from mice with OVA‑induced asthma. A total of 35,401 differentially methylated regions (DMRs) were identified between mice with OVA‑induced asthma and control mice. Of these, 3,060 were located in promoter regions and 370 of the genes containing these DMRs demonstrated an inverse correlation between methylation and gene expression. Kyoto Encyclopedia of Genes and Genomes pathway analysis identified that 368 genes were upregulated or downregulated in OVA‑induced asthma samples, including genes involved in 'chemokine signalling pathway', 'focal adhesion', 'leukocyte transendothelial migration' and 'vascular smooth muscle contraction signaling' pathways. Integrated network analysis identified four hub genes, consisting of three upregulated genes [forkhead box O1 (FOXO1), SP1 transcription factor (SP1) and amyloid β precursor protein (APP)], and one downregulated gene [RUNX family transcription factor 1 (RUNX1)], all of which demonstrated an association between DNA methylation and gene expression. These genes were highly interconnected nodes in the Ingenuity Pathway Analysis module and were functionally significant. A total of four interconnected hub genes, FOXO1, RUNX1, SP1 and APP, were identified from the integrated DNA methylation and gene expression networks involved in asthma development. These results suggested that modulating these four genes could effectively control the development of asthma.

Rheumatoid arthritis (RA) is a common systemic autoimmune disorder of unknown etiology, which threatens public health. The regulatory role of tripartite motif‑containing 22 (TRIM22) has been reported in multiple types of cancers and disease, but not in RA. The aim of the present study was therefore to elucidate the potential roles and underlying mechanisms of TRIM22 in fibroblast‑like synoviocytes (FLSs) in RA. The Gene Expression Omnibus database was used to examine TRIM22 mRNA expression levels in synovial tissue samples of patients with RA and healthy controls. TRIM22 and forkhead box C1 (FOXC1) mRNA and protein expression levels in normal FLSs and RA‑FLSs were assessed using reverse transcription‑quantitative PCR (RT‑qPCR) and western blotting, respectively. The Cell Counting Kit‑8 assay was used to assess cell proliferation. Cell apoptosis was analyzed using flow cytometry. The migratory and invasive abilities of RA‑FLSs were assessed using Transwell assays. Western blotting was used to analyze the protein expression levels of apoptosis‑related factors, MMP2, MMP9 and NF‑κB signaling pathway‑related proteins. Inflammatory factors levels were assessed via ELISA and RT‑qPCR. Furthermore, the JASPAR database, chromatin immunoprecipitation and the dual‑luciferase reporter assays were used to determine the interaction between FOXC1 and the TRIM22 promoter. The results of the present study demonstrated that TRIM22 expression levels were significantly elevated in the synovial tissue samples of patients with RA and RA‑FLSs. Moreover, FOXC1 was also significantly overexpressed in RA‑FLSs. TRIM22 knockdown significantly reduced cell proliferation, migration, invasion and the inflammatory response, whereas cell apoptosis was significantly increased. Furthermore, the results demonstrated that FOXC1 may have positively mediated TRIM22 expression via binding to the TRIM22 promoter. Moreover, FOXC1 overexpression significantly reversed the outcome of TRIM22 knockdown on the proliferation, apoptosis, migration, invasion and inflammation of RA‑FLSs. FOXC1 overexpression also significantly reversed the inactivation of the NF‑κB signaling pathway caused by TRIM22 knockdown. In summary, the present study demonstrated that TRIM22 was potentially activated via FOXC1, which contributed to the progression of RA via the NF‑κB signaling pathway.

Theaflavins (TFs) are the main bioactive polyphenols in tea and contribute to protection against oxidative stress. Excessive reactive oxygen species (ROS) accumulation can lead to the disruption of cartilage homeostasis. The present study examined the potential effects of TFs on H2O2‑induced cartilage degeneration in vitro. Cell Counting kit (CCK‑8) was used to determine cell viability, and flow cytometric analysis was used to detect ROS, apoptosis and DNA damage. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting were used to detect the expression levels of target factors. The present study revealed that TFs effectively reduced the expression of catabolic factors, including matrix metalloproteinase‑13, interleukin‑1 and cartilage glycoprotein 39. TFs inhibited ROS generation in cartilage degeneration, and suppressed apoptosis and DNA damage caused by oxidative stress. TFs also downregulated the expression levels of cleaved caspase‑3 and B‑cell lymphoma 2‑associated X protein, and the DNA damage‑related genes, ATR serine/threonine kinase and ATM serine/threonine kinase. Furthermore, TFs enhanced the activity of glutathione peroxidase 1 and catalase, but reduced the expression levels of phosphorylated (p)‑AKT serine/threonine kinase (AKT) and p‑Forkhead box O3 (FOXO3)a. Conversely, the effects of TFs on apoptosis and DNA damage were reversed by persistent activation of AKT. In conclusion, TFs prevented cartilage degeneration via AKT/FOXO3 signaling in vitro. The present study suggested that TFs may be a potential candidate drug for the prevention of cartilage degeneration.

MicroRNAs (miRNAs) are upstream regulators of gene expression and are involved in several biological processes. The purpose of the present study was to obtain a detailed spatiotemporal miRNA expression profile in mouse retina, to identify one or more miRNAs that are key to mouse retinal development and to investigate the roles and mechanisms of these miRNAs. The miRNA expression pattern of the developing mouse retina was acquired from Locked Nucleic Acid microarrays. Data were processed to identify differentially expressed miRNAs (DE‑miRNAs) using the linear model in Python 3.6. Following bioinformatics analysis and reverse transcription‑quantitative polymerase chain reaction validation, 8 miRNAs (miR‑9‑5p, miR‑130a‑3p, miR‑92a‑3p, miR‑20a‑5p, miR‑93‑5p, miR‑9‑3p, miR‑709 and miR‑124) were identified as key DE‑miRNAs with low variability during mouse retinal development. Gene Ontology analysis revealed that the target genes of the DE‑miRNAs were enriched in cellular metabolic processes. Kyoto Encyclopedia of Genes and Genomes analysis demonstrated that the target genes of the DE‑miRNAs were significantly enriched in PI3K/AKT/mTOR, class O of forkhead box transcription factors, mitogen‑activated protein kinase (MAPK), neurotrophin and transforming growth factor (TGF)‑β signaling, as well as focal adhesion and the axon guidance pathway. PI3K, AKT, PTEN, MAPK1, Son of Sevenless, sphingosine‑1‑phosphate receptor 1, BCL‑2L11, TGF‑β receptor type 1/2 and integrin α (ITGA)/ITGAB, which are key components of the aforementioned pathways and were revealed to be target genes of several of the DE‑miRNAs. The present study used a linear model to identify several DE‑miRNAs, as well as their target genes and associated pathways, which may serve crucial roles in mouse retinal development. Therefore, the results obtained in the present study may provide the groundwork for further experiments.

Precocious puberty (PP) is a developmental disorder. Hypothalamic cells can produce gonadotropin‑releasing hormone (GnRH), the final output of neuroendocrine regulation that occurs during puberty. The aim of the present study was to investigate the role of live kinase B1 (LKB1), also known as serine/threonine kinase, in the progression of PP and identify the underlying mechanisms. First, the levels of LKB1 in peripheral blood and peripheral blood mononuclear cells of children with PP were detected by reverse transcription‑quantitative (RT‑q) PCR or western blotting. After the GT1‑7 mouse hypothalamus cell line was treated with high glucose (HG) and high fat (HF), the expression of LKB1 and GnRH was tested. LKB1 was overexpressed by transfection with a pcDNA3.1 plasmid and the levels of inflammatory factors, GnRH, PP‑related factors and proteins in the AMP‑activated protein kinase (AMPK)/forkhead box protein O1 (FOXO1) pathway were determined using RT‑qPCR or western blot analysis. Subsequently, Compound C, an inhibitor of AMPK/FOXO1 signaling, was used to clarify whether the effects of LKB1 on PP were mediated by the regulation of this pathway. Results indicated that children with PP exhibited a lower LKB1 expression. In addition, HG and HF culture resulted in an enhanced GnRH expression and a reduced LKB1 expression in GT1‑7 cells. LKB1 overexpression inhibited the contents of TNF‑α, IL‑6 and GnRH in in GT1‑7 cells exposed to HG and HF and reduced the expression of PP‑related proteins, including estrogen receptor‑β, cluster of differentiation 36 and G‑protein‑coupled receptor. In addition, the expression of phosphorylated (p)‑AMPK and p‑FOXO1 was markedly downregulated following LKBI overexpression. Furthermore, compound C intervention partially diminished the inhibitory effects of LKB1‑mediated upregulation on the levels of inflammation and PP‑related factors. In conclusion, these results demonstrated that LKB1 alleviated HG‑ and HF‑induced inflammation, as well as the expression of GnRH and sexual precocity‑related genes, in GT1‑7 cells by activating the AMPK/FOXO1 signaling pathway.