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Long COVID (LC) refers to a condition characterized by a variety of lingering symptoms that persist for more than 4 to 12 weeks following the initial acute SARS-CoV-2 infection. Recent research has suggested that the FOXP4 gene could potentially be a significant factor contributing to LC. Owing to that, this study investigates FOXP4's role in LC by analyzing public datasets to understand its evolution and expression in diverse human populations and searching for drugs to reduce LC symptoms. Population genetic analysis of FOXP4 across human populations unmasks distinct genetic diversity patterns and positive selection signatures, suggesting potential population-specific susceptibilities to conditions like LC. Further, we also observed that FOXP4 experiences high expression during LC. To identify potential inhibitors, drug screening analysis identifies synthetic drugs like Glisoxepide, and natural compounds Kapurimycin A3 produced from Streptomyces sp, and Cucurbitacin B from Begonia nantoensis as promising candidates. Overall, our research contributes to understanding how FOXP4 may serve as a therapeutic target for mitigating the impact of LC., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: The clinical manifestations of COVID-19 range from asymptomatic, mild to moderate, severe, and critical disease. Host genetic variants were recognized to affect the disease severity. However, the genetic landscape differs among various populations. Therefore, we explored the variants associated with COVID-19 severity in the Guangdong population., Methods: A total of 314 subjects were selected, of which the severe and critical COVID-19 patients were defined as "cases", and the mild and moderate patients were defined as "control". Twenty-two variants in interferon-related genes and FOXP4 were genotyped using the MassARRAY technology platform., Results: IFN signaling gene MX1 rs17000900 CA + AA genotype was correlated with a reduced risk of severe COVID-19 in males (P = 0.001, OR = 0.050, 95%CI = 0.008-0.316). The AT haplotype comprised of MX1 rs17000900 and rs2071430 was more likely to protect against COVID-19 severity (P = 6.3E-03). FOXP4 rs1886814 CC genotype (P = 0.001, OR = 3.747, 95%CI = 1.746-8.043) and rs2894439 GA + AA genotype (P = 0.001, OR = 5.703, 95% CI = 2.045-15.903) were correlated with increased risk of severe COVID-19. Haplotype CA comprised of rs1886814 and rs2894439 was found to be correlated with adverse outcomes (P = 7.0E-04). FOXP4 rs1886814 CC (P = 0.0004) and rs2894439 GA + AA carriers had higher neutralizing antibody titers (P = 0.0018). The CA + AA genotype of MX1 rs17000900 tended to be correlated with lower neutralizing antibody titers than CC genotype (P = 0.0663), but the difference was not statistically significant., Conclusion: Our study found a possible association between MX1 and FOXP4 polymorphisms and the severity of COVID-19. Distinguishing high-risk patients who develop severe COVID-19 will provide clues for early intervention and individual treatment strategies., (© 2024. The Author(s).)

Objective: In recent decades, thyroid cancer (TC) has exhibited a rising incidence pattern. Elevated levels of the transcription factor FOXP4 have been strongly linked to the progression of diverse tumors; nevertheless, its specific role in thyroid cancer remains underexplored. The primary objective of this study was to elucidate the functions of FOXP4 and its associated target gene, FBXW7, in the context of thyroid cancer., Methods: FOXP4 and FBXW7 expression levels in TC tissues and cell lines were assessed through immunohistochemistry and RT-qPCR analyses. The functional aspects of FOXP4, including its effects on cell proliferation, migration capabilities, cell cycle regulation, and epithelial-mesenchymal transition (EMT), were investigated. Furthermore, the interaction between FOXP4 and FBXW7 was confirmed using chromatin immunoprecipitation (ChIP) assays. The impact of FBXW7 on FOXP4-mediated cellular phenotypes was subsequently examined. Additionally, the in vivo role of FOXP4 and FBXW7 in tumor growth was elucidated through the establishment of a murine tumor model., Results: Elevated levels of FOXP4 were observed in papillary carcinoma tissues, and patients exhibiting high FBXW7 levels showed a more favorable prognosis. KTC-1 cells displayed a concomitant increase in FOXP4 expression and decrease in FBXW7 expression. FOXP4 overexpression in these cells enhanced cell proliferation, migration capabilities, and EMT. The interaction between the FOXP4 protein and the FBXW7 promoter was confirmed, and the effects of FOXP4 were mitigated upon overexpression of FBXW7. Furthermore, knockdown of FOXP4 led to decelerated growth of transplanted tumors and increased FBXW7 levels within the tumors., Conclusion: The findings of the current study underscore the regulatory role of FOXP4 in the transcription of FBXW7 and establish a clear link between aberrations in FBXW7 expression and the manifestation of malignant phenotypes in highly aggressive TC cells., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Accumulating studies have demonstrated the important role of circular RNAs (circRNAs) in the progression of different human tumors, including non-small-cell lung cancer (NSCLC). The purpose of this study was to deeply study the function and mechanism of circ_0017956 in NSCLC. Real-time quantitative polymerase chain reaction (RT-qPCR) was applied to detect the expression of circ_0017956, microRNA-758-3p (miR-758-3p), and Forkhead Box P4 (FOXP4). Western blot was performed to determine the protein levels. Cell proliferation was examined by cell counting kit-8 (CCK-8) assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. Flow cytometry was used to evaluate the apoptosis of NSCLC cells. Transwell assay was applied to detect cell migratory and invasive capacities. The angiogenesis ability was evaluated by tube formation experiment. The target relationship between miR-758-3p and circ_0017956 or FOXP4 was confirmed by dual-luciferase reporter assay. Animal experiment was conducted to assess the effect of circ_0017956 in vivo. Circ_0017956 and FOXP4 were upregulated, while miR-758-3p was downregulated in NSCLC tissues and cells. Silencing of circ_0017956 significantly suppressed cell proliferation, migration, invasion, and angiogenesis, but promoted cell apoptosis in NSCLC cells. Mechanically, circ_0017956 functioned as a sponge for miR-758-3p and miR-758-3p could directly interact with FOXP4. Moreover, silencing of miR-758-3p or overexpression of FOXP4 could overturn the anticancer influence of circ_0017956 interference on NSCLC cells. Besides that, circ_0017956 knockdown hindered tumor growth in vivo. Altogether, circ_0017956 promoted the progression of NSCLC by regulating FOXP4 through sponging miR-758-3p., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

FOXP1 encodes a transcription factor involved in tissue regulation and cell-type-specific functions. Haploinsufficiency of FOXP1 is associated with a neurodevelopmental disorder: autosomal dominant mental retardation with language impairment with or without autistic features. More recently, heterozygous FOXP1 variants have also been shown to cause a variety of structural birth defects including central nervous system (CNS) anomalies, congenital heart defects, congenital anomalies of the kidney and urinary tract, cryptorchidism, and hypospadias. In this report, we present a previously unpublished case of an individual with congenital diaphragmatic hernia (CDH) who carries an approximately 3.8 Mb deletion. Based on this deletion, and deletions previously reported in two other individuals with CDH, we define a CDH critical region on chromosome 3p13 that includes FOXP1 and four other protein-coding genes. We also provide detailed clinical descriptions of two previously reported individuals with CDH who carry de novo, pathogenic variants in FOXP1 that are predicted to trigger nonsense-mediated mRNA decay. A subset of individuals with putatively deleterious FOXP4 variants has also been shown to develop CDH. Since FOXP proteins function as homo- or heterodimers and the homologs of FOXP1 and FOXP4 are expressed at the same time points in the embryonic mouse diaphragm, they may function together as a dimer, or in parallel as homodimers, to regulate gene expression during diaphragm development. Not all individuals with heterozygous, loss-of-function changes in FOXP1 develop CDH. Hence, we conclude that FOXP1 acts as a susceptibility factor that contributes to the development of CDH in conjunction with other genetic, epigenetic, environmental, and/or stochastic factors., Competing Interests: Conflict of Interest None declared., (Thieme. All rights reserved.)

Objective: Thyroid cancer (THCA) is the most common endocrine cancer in the world. Although most patients with THCA have a good prognosis, the prognosis of those with THCA who have an extra-glandular invasion, vascular invasion, and distant metastasis is poor. Therefore, it is very important to find potential biomarkers that can effectively predict the prognosis and progression of highly aggressive THCAs. It has been identified that forkhead box P4 (FOXP4) may be a new biomarker for the proliferation and prognosis for tumor diagnosis. However, the expression and function of FOXP4 in THCA remain to be determined., Methods: In the present study, the function of FOXP4 in cells was investigated through the comprehensive analysis of data in The Cancer Genome Atlas and combined with experiments including immunohistochemistry (IHC), colony formation, Cell Counting Kit-8 assay, wound scratch healing, and transwell invasion assay., Results: In the present study, relevant bioinformatic data showed that FOXP4 was highly expressed in THCA, which was consistent with the results of the IHC and cell experiments. Meanwhile, 10 FOXP4-related hub genes were identified as potential diagnostic genes for THCA. It was found in further experiments that FOXP4 was located in the nucleus of THCA cells, and the expression of FOXP4 in the nucleus was higher than that in the cytoplasm. FOXP4 knockdown inhibited in vitro proliferation of the THCA cells, whereas overexpression promoted the proliferation and migration of THCA cells. Furthermore, deficiency of FOXP4 induced cell-cycle arrest., Conclusion: FOXP4 might be a potential target for diagnosing and treating THCA.

Although the human papillomavirus (HPV) vaccine is effective for preventing cervical cancers, this vaccine does not eliminate pre-existing infections, and alternative strategies have been warranted. Here, we report that FOXP4 is a new target molecule for differentiation therapy of cervical intraepithelial neoplasia (CIN). An immunohistochemical study showed that FOXP4 was expressed in columnar epithelial, reserve, and immature squamous cells, but not in mature squamous cells of the normal uterine cervix. In contrast with normal mature squamous cells, FOXP4 was expressed in atypical squamous cells in CIN and squamous cell carcinoma lesions. The FOXP4-positive areas significantly increased according to the CIN stages from CIN1 to CIN3. In monolayer cultures, downregulation of FOXP4 attenuated proliferation and induced squamous differentiation in CIN1-derived HPV 16-positive W12 cells via an ELF3-dependent pathway. In organotypic raft cultures, FOXP4-downregulated W12 cells showed mature squamous phenotypes of CIN lesions. In human keratinocyte-derived HaCaT cells, FOXP4 downregulation also induced squamous differentiation via an ELF3-dependent pathway. These findings suggest that downregulation of FOXP4 inhibits cell proliferation and promotes the differentiation of atypical cells in CIN lesions. Based on these results, we propose that FOXP4 is a novel target molecule for nonsurgical CIN treatment that inhibits CIN progression by inducing squamous differentiation., (© 2022 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Papillary thyroid carcinoma, also known as PTC, is one of the commonest malignancies in the endocrine system. Long non-coding RNAs (lncRNAs) in PTC could maintain proliferative signaling, induce therapeutic resistance, activate invasion and migration, and sustain stem cell-like characteristics. In this paper, results showed that lncRNA forkhead box P4 antisense RNA 1 (FOXP4-AS1) is downregulated in PTC tissues and cell lines. Patients in TCGA cohort with a higher FOXP4-AS1 expression showed a higher disease-free interval (DFI) rate, and the expression of FOXP4-AS1 is shown to be linked to the clinical stage, T stage, N stage, and extraglandular invasion condition of the TC patients. FOXP4-AS1 is localized in the cell cytoplasmic domain of PTC cells. Functionally, upregulated FOXP4-AS1 inhibited PTC cell proliferation, apoptosis, and migration, whereas it downregulated FOXP4-AS1-promoted progression of PTC. In vivo assay also confirmed the tumor inhibitory effect of FOXP4-AS1 in PTC growth. Mechanism analysis indicated that FOXP4-AS1 can play its functions by regulating the AKT signaling pathway, and AKT inhibitor treatment could attenuate the impact of FOXP4-AS1 on PTC progression. Furthermore, FOXP4-AS1 also negatively regulates the expression of its host gene FOXP4. Collectively, we showed that FOXP4-AS1 inhibited PTC progression although AKT signaling and FOXP4-AS1 plays a tumor-suppressor role in PTC tumorigenesis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Luo, Gao, Zhou, Tang, Zhao, Zhang, Wang, Ye, Chen, Chen, Tang and Zhao.)

Beige adipocytes have a discrete developmental origin and possess notable plasticity in their thermogenic capacity in response to various environmental cues, but the transcriptional machinery controlling beige adipocyte development and thermogenesis remains largely unknown. By analyzing beige adipocyte-specific knockout mice, we identified a transcription factor, forkhead box P4 (FOXP4), that differentially governs beige adipocyte differentiation and activation. Depletion of Foxp4 in progenitor cells impaired beige cell early differentiation. However, we observed that ablation of Foxp4 in differentiated adipocytes profoundly potentiated their thermogenesis capacity upon cold exposure. Of note, the outcome of Foxp4 deficiency on UCP1-mediated thermogenesis was confined to beige adipocytes, rather than to brown adipocytes. Taken together, we suggest that FOXP4 primes beige adipocyte early differentiation, but attenuates their activation by potent transcriptional repression of the thermogenic program., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)

Malignant tumors are a grave threat to human health. Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal malignant tumor. China has a high incidence of ESCC, and its morbidity and mortality are higher than the global average. Increasingly, studies have shown that long noncoding RNAs (lncRNAs) play a vital function in the occurrence and development of tumors. Although the biological function of FOXP4-AS1 has been demonstrated in various tumors, the potential molecular mechanism of FOXP4-AS1 in ESCC is still poorly understood. The expression of FOXP4 and FOXP4-AS1 was detected in ESCC by quantitative real-time PCR (qRT-PCR) or SP immunohistochemistry (IHC). shRNA was used to silence gene expression. Apoptosis, cell cycle, MTS, colony formation, invasion and migration assays were employed to explore the biological functions of FOXP4 and FOXP4-AS1. The potential molecular mechanism of FOXP4-AS1 in ESCC was determined by dual-luciferase reporter, RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP). Here, we demonstrated that FOXP4-AS1 was significantly increased in ESCC tissues and cell lines, associated with lymph node metastasis and TNM staging. Cell function experiments showed that FOXP4-AS1 promoted the proliferation, invasion and migration ability of ESCC cells. The expression of FOXP4-AS1 and FOXP4 in ESCC tissues was positively correlated. Further research found that FOXP4-AS1, upregulated in ESCC, promotes FOXP4 expression by enriching MLL2 and H3K4me3 in the FOXP4 promoter through a "molecular scaffold". Moreover, FOXP4, a transcription factor of β-catenin, promotes the transcription of β-catenin and ultimately leads to the malignant progression of ESCC. Finally, FOXP4-AS1 may be a new therapeutic target for ESCC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Niu, Wang, Li, Guo, Guo and Dong.)

Background: Lung squamous cell carcinoma (LUSC) is one of the commonest malignancies worldwide. Long noncoding RNAs (lncRNAs) have been revealed to engage in cancer development. LncRNA RP11-116G8.5 is a new founded lncRNA that has not been clearly elucidated in LUSC., Materials and Methods: Expression levels of RNAs in LUSC cells were measured through qRT-PCR. To identify the functions of RP11-116G8.5, CCK-8 assay, colony formation assay and EdU assay were conducted in indicated LUSC cells. Mechanism experiments, including RNA pull down assay, Ago2-RIP assay and luciferase reporter assay were performed to demonstrate the interaction between RP11-116G8.5 and miR-3150b-3p/miR-6870-5p. Meanwhile, the interaction between miR-3150b-3p/miR-6870-5p and their downstream targets PHD finger protein 12 (PHF12), and forkhead box P4 (FOXP4) were also proven in the same methods., Results: RP11-116G8.5 was expressed at high level in LUSC cell lines. Down-regulated RP11-116G8.5 repressed cell proliferation, migration and invasion, but accelerated apoptosis. Furthermore, it was proven that RP11-116G8.5 could act as sponges for miR-3150b-3p and miR-6870-5p these miRNAs were found to act as cancer suppressors in LUSC cells. PHF12 and FOXP4 were verified as the target gene of miR-3150b-3p and miR-6870-5p separately. Overexpression of PHF12 and FOXP4 could reverse the repressive effect of RP11-116G8.5 knockdown on LUSC progression. Additionally, Paired Box 5 (PAX-5) was proven to be the transcription factor for RP11-116G8.5 in LUSC cells., Conclusions: LncRNA RP11-116G8.5 promotes malignant behaviors of LUSC through sponging miR-3150b-3p/miR-6870-5p to upregulate PHF12/FOXP4 expression., Availability of Data: The research data is confidential., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Circular RNAs (circRNAs) have been demonstrated to play critical roles in the initiation and development of breast cancer (BC). This study aimed to uncover the regulatory roles of a novel circRNA, circRPPH1 (hsa_circ_0000514) in BC progression. CircRPPH1, miR-296-5p and FOXP4 levels were determined by qRT-PCR. CircRPPH1 stability was detected in response to ribonuclease (RNase) R digestion and actinomycin D treatment. Cell growth, migration and invasion were evaluated using various functional experiments. Protein levels of proliferating cell nuclear antigen (PCNA), matrix metalloproteinase 9 (MMP-9), hexokinase 2 (HK2) and forkhead box protein 4 (FOXP4) were measured by Western blotting. Metabolic alterations of BC cells were evaluated using commercial kits. The interaction between miR-296-5p and circRPPH1/FOXP4 was assessed using dual-luciferase assay, RNA pull-down, and RNA immunoprecipitation (RIP) assay. The in vivo tumorigenesis was assessed in nude mice. According to the results, up-regulation of circRPPH1 was closely correlated with the poor prognosis of BC patients. Functional experiments showed that knockdown of circRPPH1 repressed BC cell growth, migration, invasion, glycolysis, and in vivo tumor growth. In addition, circRPPH1 could sponge miR-296-5p to enhance FOXP4 expression in BC cells. miR-296-5p inhibition or FOXP4 overexpression restored the malignant properties of circRPPH1-silenced BC cells. Thus, circRPPH1 promoted BC malignant progression through regulating miR-296-5p/FOXP4 axis, indicating a possible novel therapeutic strategy involving circRNA for BC patients., Competing Interests: None., (AJTR Copyright © 2021.)

Ovarian cancer (OV) is the main cause of deaths worldwide in female reproductive system malignancies. Enhancer RNAs (eRNAs) are derived from the transcription of enhancers and has attracted increasing attention in cancers recently. However, the biological functions and clinical significance of eRNAs in OV have not been well described presently. We used an integrated data analysis to identify prognostic-related eRNAs in OV. Tissue-specific enhancer-derived RNAs and their regulating genes were considered as putative eRNA-target pairs using the computational pipeline PreSTIGE. Gene expression profiles and clinical data of OV and 32 other cancer types were obtained from the UCSC Xena platform. Altogether, 71 eRNAs candidates showed significant correlation with overall survival (OS) of OV samples (Kaplan-Meier log-rank test, P<0.05). Among which, 23 were determined to be correlated with their potential target genes (Spearman's r > 0.3, P<0.001). It was found that among the 23 prognostic-related eRNAs, the expression of forkhead box P4 antisense RNA 1 (FOXP4-AS1) had the highest positive correlation with its predicted target gene FOXP4 (Spearman's r = 0.61). Moreover, the results were further validated by RT-qPCR analysis in an independent OV cohort. Our results suggested the eRNA FOXP4-AS1 expression index may be a favorable independent prognostic biomarker candidate in OV., (© 2021 The Author(s).)

Purpose: Heterozygous pathogenic variants in various FOXP genes cause specific developmental disorders. The phenotype associated with heterozygous variants in FOXP4 has not been previously described., Methods: We assembled a cohort of eight individuals with heterozygous and mostly de novo variants in FOXP4: seven individuals with six different missense variants and one individual with a frameshift variant. We collected clinical data to delineate the phenotypic spectrum, and used in silico analyses and functional cell-based assays to assess pathogenicity of the variants., Results: We collected clinical data for six individuals: five individuals with a missense variant in the forkhead box DNA-binding domain of FOXP4, and one individual with a truncating variant. Overlapping features included speech and language delays, growth abnormalities, congenital diaphragmatic hernia, cervical spine abnormalities, and ptosis. Luciferase assays showed loss-of-function effects for all these variants, and aberrant subcellular localization patterns were seen in a subset. The remaining two missense variants were located outside the functional domains of FOXP4, and showed transcriptional repressor capacities and localization patterns similar to the wild-type protein., Conclusion: Collectively, our findings show that heterozygous loss-of-function variants in FOXP4 are associated with an autosomal dominant neurodevelopmental disorder with speech/language delays, growth defects, and variable congenital abnormalities.

Background: Non-small cell lung cancer (NSCLC) is one of the most malignant cancers worldwide and its pathogenesis is not completely clear. In this study, we explored the functions and mechanisms of exosomes transferring miR-3180-3p in NSCLC progression., Methods: The expression levels of miR-3180-3p in NSCLC tissues and paracarcinoma tissues was obtained from the GEO database (GEO: GSE53882). Exosomes derived from A549 cells were identified. Proliferation, migration and invasion were measured after treatment with exosomal miR-3180-3p or transfection using miR-3180-3p mimics. The relationship between miR-3180-3p and forkhead box P4 (FOXP4) was predicted using a bioinformatic tool and measured using a dual-luciferase reporter gene assay and western blotting. Finally, a mouse xenograft model of NSCLC cells was established to verify the function of exosomal miR-3180-3p in vivo., Results: We found that miR-3180-3p decreased in both NSCLC cell lines and patient tissues. Overexpression of miR-3180-3p or treatment with exosomal miR-3180-3p significantly suppressed cell proliferation and metastasis in NSCLC cell lines. Subsequently, we found miR-3180-3p downregulated FOXP4 protein expression levels. Furthermore, the volumes and weights of nude mouse tumors expressing exosomal miR-3180-3p were significantly reduced., Conclusions: Exosomal miR-3180-3p suppresses NSCLC progression by downregulating FOXP4 expression., Key Points: SIGNIFICANT FINDINGS OF THE STUDY: We found that exosomal miR-3180-3p suppressed NSCLC progression and also identified a miR-3180-3p target gene. These findings provide a foundation to determine innovative therapeutic strategies., What This Study Adds: This study contributes to research investigating exosomal containing miRNAs., (© 2020 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.)

Forkhead box transcription factors have been shown to be involved in various developmental and differentiation processes. In particular, members of the FoxP family have been previously characterized in depth for their participation in the regulation of lung and neuronal cell differentiation and T-cell development and function; however, their role in adipocyte functionality has not yet been investigated. Here, we report for the first time that Forkhead box P4 (FoxP4) is expressed at high levels in subcutaneous fat depots and mature thermogenic adipocytes. Through molecular and gene expression analyses, we revealed that FoxP4 is induced in response to thermogenic stimuli, both in vivo and in isolated cells, and is regulated directly by the heat shock factor protein 1 through a heat shock response element identified in the proximal promoter region of FoxP4. Further detailed analysis involving chromatin immunoprecipitation and luciferase assays demonstrated that FoxP4 directly controls the levels of uncoupling protein 1, a key regulator of thermogenesis that uncouples fatty acid oxidation from ATP production. In addition, through our gain-of-function and loss-of-function studies, we showed that FoxP4 regulates the expression of a number of classic brown and beige fat genes and affects oxygen consumption in isolated adipocytes. Overall, our data demonstrate for the first time the novel role of FoxP4 in the regulation of thermogenic adipocyte functionality., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Esophageal squamous cell carcinoma (ESCC) belongs to one of the most common malignant tumors worldwide and possesses high mortality. Long non-coding RNAs (lncRNAs) have been demonstrated to be essential biological participants in the progression of ESCC. On the basis of bio-informatics prediction, forkhead box P4 antisense RNA 1 (FOXP4-AS1) and forkhead box P4 (FOXP4) were upregulated in esophageal carcinoma samples and were positively correlated with each other. The present study aimed to explore the function of FOXP4-AS1 and FOXP4 in ESCC cells. Function assays disclosed that knockdown of FOXP4-AS1 or FOXP4 efficiently suppressed cell proliferation and induced cell apoptosis. Moreover, FOXP4-AS1 positively regulated FOXP4 by interacting with insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) to stabilize FOXP4 messenger RNA. In addition, FOXP4-AS1 could upregulate the expression of FOXP4 by sponging miR-3184-5p. Finally, we found that Yin Yang 1 (YY1) is a transcription factor that can transcriptionally activate both FOXP4-AS1 and FOXP4 in ESCC cells. In a word, YY1-induced upregulation of FOXP4-AS1 and FOXP4 promote the proliferation of ESCC cells., (© 2020 International Federation for Cell Biology.)

MicroRNAs (miRNAs) belong to the subgroup of small noncoding RNAs, which typically serve as important gene regulators to participate in different biological events, such as tumor cell growth and apoptosis. Recent studies indicated microRNA-4651 (miR-4651) was involved in hepatocellular carcinoma (HCC) progression. The certain role of miRNA-4651 during the progression of HCC, however, remains unclear. Herein, we investigated the mRNA expression level of miR-4651 in HCC tissues and HCC cell lines and found miR-4651 was noticeably down-regulated compared with the normal liver tissues and QSG-7701 cell line, respectively. Then, miR-4561 overexpression obviously repressed the proliferation and promoted apoptosis in two HCC cell lines. Interestingly, we further identified that miR-4561 could directly interact with FOXP4 in HCC cells by using bio-informatic method and report assay. Moreover, forced expression of FOXP4 showed an opposite effect compared with miR-4561 in HCC cell lines. Hence, our findings strongly indicated that miR-4561 regulated the HCC cell growth and apoptosis mainly through targeting the FOXP4 genes. Clinically, the miR-4561/FOXP4 axis might be a potential target for therapeutic application of HCC patient treatment., (© 2020 The Author(s).)

Objective: Laryngeal cancer is a common malignant tumor in the ENT, of which laryngeal squamous cell carcinoma (LSCC) accounts for more than 90% of laryngeal cancer. The purpose of this study is to investigate the regulatory mechanism of lncRNA SNHG16 in LSCC., Materials and Methods: Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to measure mRNA expression. Cell Counting Kit (CCK-8), Transwell and luciferase reporter assays, flow cytometric analysis and Western blot analysis were used to investigate the function of lncRNA SNHG16 in LSCC., Results: SNHG16 expression was increased in LSCC tissues and cells. The abnormal expression of SNHG16 was associated with clinical stage and lymph node metastasis in LSCC patients. In addition, knockdown of SNHG16 restrained cell proliferation, migration and invasion in LSCC. More importantly, SNHG16 acted as a competitive endogenous RNA in LSCC and regulated FOXP4 expression by making miR-877-5p sponge. Further, SNHG16 promoted LSCC progression by interacting with miR-877-5p and FOXP4., Conclusion: LncRNA SNHG16 promotes the progression of LSCC by sponging miR-877-5p and upregulating FOXP4., Competing Interests: The authors report no conflicts of interest in this work., (© 2020 Wang et al.)

Mutations in the transcription factors FOXP1 and FOXP2 are associated with speech impairments. FOXP1 is additionally linked to cognitive deficits, as is FOXP4. These FoxP proteins are highly conserved in vertebrates and expressed in comparable brain regions, including the striatum. In male zebra finches, experimental manipulation of FoxP2 in Area X, a striatal song nucleus essential for vocal production learning, affects song development, adult song production, dendritic spine density, and dopamine-regulated synaptic transmission of striatal neurons. We previously showed that, in the majority of Area X neurons FoxP1, FoxP2, and FoxP4 are coexpressed, can dimerize and multimerize with each other and differentially regulate the expression of target genes. These findings raise the possibility that FoxP1, FoxP2, and FoxP4 (FoxP1/2/4) affect neural function differently and in turn vocal learning. To address this directly, we downregulated FoxP1 or FoxP4 in Area X of juvenile zebra finches and compared the resulting song phenotypes with the previously described inaccurate and incomplete song learning after FoxP2 knockdown. We found that experimental downregulation of FoxP1 and FoxP4 led to impaired song learning with partly similar features as those reported for FoxP2 knockdowns. However, there were also specific differences between the groups, leading us to suggest that specific features of the song are differentially impacted by developmental manipulations of FoxP1/2/4 expression in Area X. SIGNIFICANCE STATEMENT We compared the effects of experimentally reduced expression of the transcription factors FoxP1, FoxP2, and FoxP4 in a striatal song nucleus, Area X, on vocal production learning in juvenile male zebra finches. We show, for the first time, that these temporally and spatially precise manipulations of the three FoxPs affect spectral and temporal song features differentially. This is important because it raises the possibility that the different FoxPs control different aspects of vocal learning through combinatorial gene expression or by acting in different microcircuits within Area X. These results are consistent with the deleterious effects of human FOXP1 and FOXP2 mutations on speech and language and add FOXP4 as a possible candidate gene for vocal disorders., (Copyright © 2019 the authors.)

In recent years, circular RNAs (circRNAs) have been identified to be essential regulators of various human cancers. However, knowledge of the functions of circRNAs in prostate cancer remains very limited. The correlation between circABCC4 and human cancer is largely unknown. This study aims to investigate the biological functions of circABCC4 in prostate cancer progression and illustrate the underlying mechanism. We found that circABCC4 was remarkably up-regulated in prostate cancer tissues and cell lines and promoted FOXP4 expression by sponging miR-1182 in prostate cancer cells. CircABCC4 knockdown markedly suppressed prostate cancer cell proliferation, cell-cycle progression, migration and invasion in vitro. Furthermore, silencing of the circRNA also delayed tumor growth in vivo. Taken together, our findings indicated that circABCC4 facilitates the malignant behaviour of prostate cancer by promoting FOXP4 expression through sponging of miR-1182. The circABCC4-miR-1182-FOXP4 regulatory loop may be a promising therapeutic target for prostate cancer intervention., (© 2019 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Long non-coding RNAs (lncRNAs) function as critical regulator in human cancers. However, the biological regulatory mechanisms of lncRNAs in Ewing's sarcoma are still elusive. This study tries to investigate the clinical significance and pathological role of lncRNA SOX2 overlapping transcript (SOX2OT) in Ewing's sarcoma progression. SOX2OT was identified to be up-regulated in Ewing's sarcoma tissue and cells. In vitro, SOX2OT knockdown suppressed Ewing's sarcoma cells proliferation and invasion, and triggered apoptosis. In vivo xenograft assays, SOX2OT knockdown significantly inhibited Ewing's sarcoma growth. With the help of bioinformatics analysis and luciferase assay, SOX2OT was validated to harbor miR-363, acting as miRNA sponge or competing endogenous RNA (ceRNA). Furthermore, FOXP4 was validated to be the target protein of miR-363. Western blot and RT-PCR confirmed that SOX2OT was positively correlated with FOXP4 protein via sponging miR-363, forming a negative cascade regulation. In conclusion, our study realizes that SOX2OT acted as oncogene in the tumorigenesis of Ewing's sarcoma, suggesting the SOX2OT/miR-363/FOXP4 pathway in Ewing's sarcoma., Competing Interests: None.

Background: Family of forkhead box transcription factors has been found to play key roles in multiple types of cancer., Materials and Methods: Our study is to decipher the effects of FOXP4 in human breast cancer (BC). Quantitative real-time polymerase chain reaction and Western blot analyses were performed to determine the mRNA and protein expressions of FOXP4 in BC tissue samples and cell lines. The gain and loss of function assay were used to explore the detailed roles of FOXP4 in breast cell lines, including MDA-MB-231 and MCF-7 cells. Its effect on BC growth, migration, and invasion were evaluated by colony formation assay, CCK-8 assay, wound-healing assay, and transwell invasion assay, respectively., Results: Our findings revealed that FOXP4 promotes cell proliferation, migration, as well as invasion of BC cells. Furthermore, FOXP4 also facilitates epithelial-mesenchymal transition. ChIP, qChIP assay, and dual luciferase reporter assay were used to examine whether Snail is a downstream target of FOXP4. Moreover, overexpression of Snail could partially rescue the effects of FOXP4 inhibition on cancer cell migration and invasion., Conclusion: Our findings revealed that FOXP4 is a critical regulator in BC., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Previous studies have indicated that FoxP1, FoxP2 and FoxP3 play important roles in hepatocellular carcinoma (HCC). However, the effect of FoxP4 in HCC requires further elucidation. The aim of the present study was to explore the roles of FoxP4 in HCC and further decipher the detailed mechanism. In present study, it was found that FoxP4, which is overexpressed in HCC tissues and cell lines, facilitated EMT in HCC cell lines through regulation of Slug. First, increased expression of FoxP4 was identified in 110 pairs of human HCC tumor and their adjacent normal tissues. In addition, the association between FoxP4 expression and clinicopathological features of HCC patients indicated that FoxP4 played vital roles in HCC development. Subsequently, gain- and loss-of-function experiments indicated that FoxP4 promoted cellular proliferation, migration as well invasion. In addition, EMT, a key mechanism during cancer metastasis, was regulated by FoxP4. Furthermore, ChIP and qChIP as well as luciferase reporter assays indicated that Slug, an EMT-associated transcription factor, was transcriptionally regulated by FoxP4. In conclusion, FoxP4 functioned as a tumor promoter in HCC cells by transcriptionally regulating Slug, and the present study highlighted the potential effects of FoxP4 on the prognosis and treatment of HCC.

MicroRNAs are noncoding RNAs of 21 to 23 nucleotides in length that play important roles in almost all biological pathways. The roles of microRNA-299-3p in the development and progression of oral squamous cell carcinoma remain unclear. Expression level of microRNA-299-3p in oral squamous cell carcinoma cell lines was analyzed. Then, the effects of microRNA-299-3p on oral squamous cell carcinoma cell proliferation and migration were investigated. Moreover, bioinformation algorithm and Western blot were conducted to explore whether forkhead box P4 was a direct target of miR-299-3p. We showed that microRNA-299-3p expression was significantly reduced in oral squamous cell carcinoma cell lines. Next, overexpression of microRNA-299-3p was found to inhibit oral squamous cell carcinoma cell proliferation and migration but promote apoptosis. In addition, forkhead box P4 was identified as a functional target of microRNA-299-3p. Our results provide a new perspective for the mechanisms underlying the progression of oral squamous cell carcinoma and a novel target for the treatment of oral squamous cell carcinoma.

References: ATCC. www.lgcstandards-atcc.org/Products/All/CRL-1441.aspx?geo&#95;country=it Memorial Sloan Kettering Cancer Cancer. https://www.mskcc.org/research-advantage/support/technology/tangiblematerial/sk-nep-1-human-ewing-sarcoma-cell-line.

Recently, circular RNAs (circRNAs) have been demonstrated as essential regulators in human cancers. However, the function and mechanism of circRNAs in breast cancer (BC) remain largely unknown and require to be investigated. In the present study, we found that circMYO9B was highly expressed in BC tissues by bioinformatics analysis. And we showed that circMYO9B expression was positively correlated with patients' prognosis. Moreover, we found that circMYO9B knockdown significantly suppressed the proliferation, migration and invasion of BC cells in vitro. In vivo assays also indicated that circMYO9B silence delayed tumor growth. In mechanism, we found that circMYO9B promoted the expression of FOXP4 by sponging miR-4316 in BC cells. We showed that the expression of miR-4316 was inversely associated with that of circMYO9B or FOXP4 in BC tissues. Finally, we found that restoration of FOXP4 expression significantly reversed the effects of circMYO9B knockdown on BC cell proliferation, migration and invasion. In conclusion, our findings demonstrated a key role of circMYO9B/miR-4316/FOXP4 axis in regulating BC progression., (Copyright © 2018 Elsevier Inc. All rights reserved.)

The Forkhead transcription factor FOXP2 is implicated in speech perception and production. The avian homolog, FoxP2 contributes to song learning and production in birds. In human cell lines, transcriptional activity of FOXP2 requires homo-dimerization or dimerization with paralogs FOXP1 or FOXP4. Whether FoxP dimerization occurs in the brain is unknown. We recently showed that FoxP1, FoxP2 and FoxP4 (FoxP1/2/4) proteins are co-expressed in neurons of Area X, a song control region in zebra finches. We now report on dimer- and oligomerization of zebra finch FoxPs and how this affects transcription. In cell lines and in the brain we identify homo- and hetero-dimers, and an oligomer composed of FoxP1/2/4. We further show that FoxP1/2 but not FoxP4 bind to the regulatory region of the target gene Contactin-associated protein-like 2 ( CNTNAP2 ). In addition, we demonstrate that FoxP1/4 bind to the regulatory region of very low density lipoprotein receptor ( VLDLR ), as has been shown for FoxP2 previously. Interestingly, FoxP1/2/4 individually or in combinations regulate the promoters for SV40, zebra finch VLDLR and CNTNAP2 differentially. These data exemplify the potential for complex transcriptional regulation of FoxP1/2/4, highlighting the need for future functional studies dissecting their differential regulation in the brain.

Epigenetic changes in articular chondrocytes are associated with osteoarthritis (OA) disease progression. Numerous studies have identified differentially methylated cytosines in OA tissues; however, the consequences of altered CpG methylation at single nucleotides on gene expression and phenotypes are difficult to predict. With the objective of detecting novel genes relevant to OA, we conducted a genome-wide assessment of differentially methylated sites (DMSs) and differentially methylated regions (DMRs). DNA was extracted from visually damaged and normal appearing, non-damaged human knee articular cartilage from the same joint and then subjected to reduced representation bisulfite sequencing. DMRs were identified using a genome-wide systematic bioinformatics approach. A sliding-window of 500 bp was used for screening the genome for regions with clusters of DMSs. Gene expression levels were assessed and cell culture demethylation experiments were performed to further examine top candidate genes associated with damaged articular cartilage. More than 1000 DMRs were detected in damaged osteoarthritic cartilage. Nineteen of these contained five or more DMSs and were located in gene promoters or first introns and exons. Gene expression assessment revealed that hypermethylated DMRs in damaged samples were more consistently associated with gene repression than hypomethylated DMRs were with gene activation. Accordingly, a demethylation agent induced expression of most hypermethylated genes in chondrocytes. Our study revealed the utility of a systematic DMR search as an alternative to focusing on single nucleotide data. In particular, this approach uncovered promising candidates for functional studies such as the hypermethylated protein-coding genes FOXP4 and SHROOM1, which appear to be linked to OA pathology in humans and warrant further investigation., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Family of forkhead box transcription factors, including forkhead box P4 (FOXP4), plays an important role in oncogenesis. The current study is to evaluate the role of FOXP4 in regulating human non-small cell lung cancer (NSCLC). Quantitative RT-PCR and Western blot were performed to evaluate the gene and protein expressions of FOXP4 in six NSCLC cell lines and 55 NSCLC patients. Lentivirus of small hairpin RNA (FOXP4-shRNA) was used to downregulate FOXP4 in NSCLC cell lines A549 and H1703 cells. Its effect on NSCLC growth, invasion, and cell cycle were evaluated by cell proliferation assay, migration assay, and cell cycle assay, respectively. Dual luciferase assay and Western blot were used to examine whether microRNA-138 (miR-138) was an upstream regulator of FOXP4. The dependence of FOXP4 on miR-138 associated signaling pathway was evaluated by ectopically overexpressing enhancer of zeste homolog 2 (EZH2), a known miR-138 target in NSCLC. FOXP4 was highly expressed in both NSCLC cell lines and NSCLC patients. FOXP4 downregulation by FOXP4-shRNA markedly reduced cancer cell growth and invasion, as well as induced cell cycle arrest in A549 and H1703 cells. MiR-138 was confirmed to be an upstream regulator of FOXP4 and directly regulated FOXP4 expression in A549 and H1703 cells. FOXP4 downregulation-mediated inhibition on cancer cell growth and invasion was independent on overexpressing EZH2, another direct target of miR-138 in NSCLC. Our data demonstrated that FOXP4 was a critical regulator in NSCLC and independently associated with miR-138 regulation.

Osteoblast induction and differentiation in developing long bones is dynamically controlled by the opposing action of transcriptional activators and repressors. In contrast to the long list of activators that have been discovered over past decades, the network of repressors is not well-defined. Here we identify the expression of Foxp1/2/4 proteins, comprised of Forkhead-box (Fox) transcription factors of the Foxp subfamily, in both perichondrial skeletal progenitors and proliferating chondrocytes during endochondral ossification. Mice carrying loss-of-function and gain-of-function Foxp mutations had gross defects in appendicular skeleton formation. At the cellular level, over-expression of Foxp1/2/4 in chondroctyes abrogated osteoblast formation and chondrocyte hypertrophy. Conversely, single or compound deficiency of Foxp1/2/4 in skeletal progenitors or chondrocytes resulted in premature osteoblast differentiation in the perichondrium, coupled with impaired proliferation, survival, and hypertrophy of chondrocytes in the growth plate. Foxp1/2/4 and Runx2 proteins interacted in vitro and in vivo, and Foxp1/2/4 repressed Runx2 transactivation function in heterologous cells. This study establishes Foxp1/2/4 proteins as coordinators of osteogenesis and chondrocyte hypertrophy in developing long bones and suggests that a novel transcriptional repressor network involving Foxp1/2/4 may regulate Runx2 during endochondral ossification., (Copyright © 2014 Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) are a class of small, non-coding RNAs, which have demonstrated to important gene regulators, and have critical roles in diverse biological processes including cancer cell proliferation. Previous studies suggested microRNA-338-3p (miR-338-3p) was down-regulated and play tumor suppressor roles in gastric cancer, colorectal carcinoma and lung cancer. However, the role of miR-338-3p in hepatocellular carcinoma (HCC) is still unclear. In this study, we analyzed the expression of miR-338-3p in HCC tissues and HCC cell lines. We find that miR-338-3p was downregulated in HCC tissues and cell lines. Then functional studies demonstrate ectopic miR-338-3p expression significantly suppressed the in vitro proliferation and colony formation of HCC cells and cause to cell cycle arrest. Using bio-informatic method and report assay we identified a novel miR-338-3p target, FOXP4 in HCC cells. Furthermore, knockdown of FOXP4 have the similar effects in HCC corrected with miR-338-3p. These findings suggest that miR-338-3p regulates survival of HCC cells partially through the downregulation of FOXP4. Therefore, targeting with the miR-338-3p/FOXP4 axis might serve as a novel therapeutic application to treat HCC patients.