FOXP4 promotes laryngeal squamous cell carcinoma progression through directly targeting LEF‑1

Transcription factor FOXP4 inversely governs tumor suppressor genes and contributes to thyroid cancer progression

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.

The functions of FOXP transcription factors and their regulation by post-translational modifications

The forkhead box subfamily P (FOXP) of transcription factors, consisting of FOXP1, FOXP2, FOXP3, and FOXP4, is involved in the regulation of multisystemic functioning. Disruption of the transcriptional activity of FOXP proteins leads to neurodevelopmental disorders and immunological diseases, as well as the suppression or promotion of carcinogenesis. The transcriptional activities of FOXP proteins are directly or indirectly regulated by diverse post-translational modifications, including phosphorylation, ubiquitination, SUMOylation, acetylation, O-GlcNAcylation, and methylation. Here, we discuss how post-translational modifications modulate the multiple functions of FOXP proteins and examine the implications for tumorigenesis and cancer therapy.

FOXP family DNA methylation correlates with immune infiltration and prognostic value in NSCLC

Background: Forkhead box P (FOXP) family was introduced as a double-edged sword in tumorigenesis and influenced immunotherapy response by modulating host immunity. This study aimed to summarize the involvement of the FOXP family in non-small cell lung cancer (NSCLC).

Methods: The UALCAN, Gene Expression Profiling Interactive Analysis (GEPIA), and Reverse transcription-quantitative polymerase chain reaction (RT‒qPCR) were used to analyse the expression levels of the FOXP family in NSCLC. The prognostic impact was evaluated using Kaplan-Meier Plotter. MethSurv, UALCAN, and cBioPortal were applied to analyse the DNA methylation and mutation status of the FOXP family respectively. COEXPEDIA, STRING, and GeneMANIA were used to explore the interaction mechanism. Finally, TISIDB was used to investigate all of the immune-related characteristics regulated by the FOXP family.

Results: The expression levels of FOXP1/3/4 were dysregulated in NSCLC tissues than that in normal tissues. Groups with low expression levels of FOXP1/4 and high expression levels of FOXP2/3 were associated with poor prognosis in NSCLC. The transcriptional levels of FOXP2/3/4 were correlated with DNA methylation in NSCLC. FOXP1/3/4 DNA methylation were correlated with prognosis. Pathway enrichment analysis indicated the FOXP family was mainly related to immune-related pathways. After DNA methylation, the correlations between FOXP family and immune factors were opposite to that before alteration in NSCLC.

Conclusion: This study elucidated FOXP family could serve as vital diagnostic and prognostic biomarkers in NSCLC. Our study highlighted novel potential functions of FOXP family DNA methylation in regulation of immune-related signatures in NSCLC.

Epithelial-to-Mesenchymal Transition in Metastasis: Focus on Laryngeal Carcinoma

In epithelial neoplasms, such as laryngeal carcinoma, the survival indexes deteriorate abruptly when the tumor becomes metastatic. A molecular phenomenon that normally appears during embryogenesis, epithelial-to-mesenchymal transition (EMT), is reactivated at the initial stage of metastasis when tumor cells invade the adjacent stroma. The hallmarks of this phenomenon are the abolishment of the epithelial and acquisition of mesenchymal traits by tumor cells which enhance their migratory capacity. EMT signaling is mediated by complex molecular pathways that regulate the expression of crucial molecules contributing to the tumor’s metastatic potential. Effectors of EMT include loss of adhesion, cytoskeleton remodeling, evasion of apoptosis and immune surveillance, upregulation of metalloproteinases, neovascularization, acquisition of stem-cell properties, and the activation of tumor stroma. However, the current approach to EMT involves a holistic model that incorporates the acquisition of potentials beyond mesenchymal transition. As EMT is inevitably associated with a reverse mesenchymal-to-epithelial transition (MET), a model of partial EMT is currently accepted, signifying the cell plasticity associated with invasion and metastasis. In this review, we identify the cumulative evidence which suggests that various aspects of EMT theory apply to laryngeal carcinoma, a tumor of significant morbidity and mortality, introducing novel molecular targets with prognostic and therapeutic potential.

FOXP4 promotes proliferation of human spermatogonial stem cells

Continuous self-renewal and differentiation of spermatogonial stem cells (SSCs) is vital for maintenance of adult spermatogenesis. Although several spermatogonial stem cell regulators have been extensively investigated in rodents, regulatory mechanisms of human SSC self-renewal and differentiation have not been fully established. We analyzed single-cell sequencing data from the human testis and found that forkhead box P4 (FOXP4) expression gradually increased with development of SSCs. Further analysis of its expression patterns in human testicular tissues revealed that FOXP4 specifically marks a subset of spermatogonia with stem cell potential. Conditional inactivation of FOXP4 in human SSC lines suppressed SSC proliferation and significantly activated apoptosis. FOXP4 expressions were markedly suppressed in tissues with dysregulated spermatogenesis. These findings imply that FOXP4 is involved in human SSC proliferation, which will help elucidate on the mechanisms controlling the fate decisions in human SSCs.

LncRNA SNHG16 promotes proliferation and migration in laryngeal squamous cell carcinoma via the miR-140-5p/NFAT5/Wnt/β-catenin pathway axis

BACKGROUND

Recent studies demonstrate that long noncoding RNAs (lncRNAs) are involved in the development of various cancers. Many lncRNAs were reported to abnormally express in laryngeal squamous cell carcinoma (LSCC) and play pivotal roles in its development. LncRNA small nucleolar RNA host gene 16 (SNHG16) was previously validated as an oncogene in hepatocellular carcinoma. Nevertheless, the biological role of SNHG16 in LSCC still needs more explorations. The goal of this assay is to explore the function and molecular mechanism of lncRNA SNHG16 in the development of LSCC.

METHODS AND RESULTS

First, RT-qPCR demonstrated the upregulation of SNHG16 in LSCC cells and tissues. Loss-of-function assays determined the inhibitive influence of SNHG16 downregulation on cell viability, growth, and migration in LSCC. Furthermore, SNHG16 bound with miR-140-5p in LSCC. MiR-140-5p overexpression suppressed LSCC cell proliferation and migration. NFAT5 was identified as a direct target of miR-140-5p. Through rescue experiments, overexpression of NFAT5 reversed SNHG16 knockdown-mediated suppression on cell viability, growth, and migration in LSCC. Additionally, NFAT5 overexpression activated while NFAT5 downregulation inhibited the Wnt/β-catenin signaling pathway.

CONCLUSION

LncRNA SNHG16 is upregulated in LSCC and contributes to the development of LSCC via regulating the miR-140-5p/NFAT5/Wnt/β-catenin pathway axis. The SNHG16/miR-140-5p/NFAT5/Wnt/β-catenin pathway axis might provide a novel strategy for LSCC treatment.