A growing amount of evidence has confirmed the crucial role of the prolyl isomerase PIN1 in aging and age-related diseases. However, the mechanism of PIN1 in age-related hearing loss (ARHL) remains unclear. Pathologically, ARHL is primarily due to the loss and dysfunction of hair cells (HCs) and spiral ganglion cells (SGCs) in the cochlea. Therefore, in this study, we aimed to investigate the role of PIN1 in protecting hair cells and auditory HEI-OC1 cells from senescence. Enzyme-linked immunosorbent assays, immunohistochemistry, and immunofluorescence were used to detect the PIN1 protein level in the serum of ARHL patients and C57BL/6 mice in different groups, and in the SGCs and HCs of young and aged C57BL/6 mice. In addition, a model of HEI-OC1 cell senescence induced by H2O2 was used. Adult C57BL/6 mice were treated with juglone, or juglone and NAC, for 4 weeks. Interestingly, we found that the PIN1 protein expression decreased in the serum of patients with ARHL, in senescent HEI-OC1 cells, and in the cochlea of aged mice. Moreover, under H2O2 and juglone treatment, a large amount of ROS was produced, and phosphorylation of p53 was induced. Importantly, PIN1 expression was significantly increased by treatment with the p53 inhibitor pifithrin-α. Overexpression of PIN1 reversed the increased level of p-p53 and rescued HEI-OC1 cells from senescence. Furthermore, PIN1 mediated cellular senescence by the PI3K/Akt/mTOR signaling pathway. In vivo data from C57BL/6 mice showed that treatment with juglone led to hearing loss. Taken together, these findings demonstrated that PIN1 may act as a vital modulator in hair cell and HEI-OC1 cell senescence.

Laryngeal squamous cell carcinoma (LSCC) is an aggressive and lethal malignant neoplasm with extremely poor prognoses. Accumulating evidence has indicated that preferentially expressed antigen in melanoma (PRAME) is correlated with several kinds of cancers. However, there is little direct evidence to substantiate the biological function of PRAME in LSCC. The purpose of the current study is to explore the oncogenic role of PRAME in LSCC. PRAME expression was analyzed in 57 pairs of LSCC tumor tissue samples through quantitative real-time PCR, and the correlation between PRAME and clinicopathological features was analyzed. The result indicated that PRAME was overexpressed in the LSCC patients and correlated with the TNM staging and lymphatic metastasis. The biological functions and molecular mechanism of PRAME in LSCC progression were investigated through in vitro and in vivo assays. Functional studies confirmed that PRAME facilitated the proliferation, invasion, migration, and epithelial–mesenchymal transition of LSCC cells, and PRAME also promoted tumor growth in vivo. HDAC5 was identified as an upstream regulator that can affect the expression of PRAME. Moreover, PRAME played the role at least partially by activating PI3K/AKT/mTOR pathways. The above findings elucidate that PRAME may be a valuable oncogene target, contributing to the diagnosis and therapy of LSCC.

The present study aimed to investigate LINC00278 expression in laryngeal squamous cell carcinoma (LSCC) and its involvement in the process of proliferation, migration, and invasion, providing a rationale for mining potential diagnostic and therapeutic targets of LSCC. Univariate and multivariate Cox regression analyses were performed to identify optimal prognostic lncRNAs. MTS, colony formation, wound healing, and Transwell invasion assays were used to determine the effects of LINC00278 overexpression on the proliferation, migration, and invasion of cancer cells. The expressions of signaling pathway-related proteins and epithelial-mesenchymal transition (EMT) marker proteins were detected using western blot. The chromatin immunoprecipitation (ChIP) and dual-luciferase reporter assays were performed to demonstrate the binding of ETS proto-oncogene 1, transcription factor (ETS1), and LINC00278 promoter region. The molecular targets of LINC00278 were identified by RNA sequencing analysis and co-expression analysis. Kaplan-Meier analysis and CIBERSORT algorithm were used to analyze survival and immune cell infiltration based on LINC00278, COL4A1, and COL4A2. Multivariate Cox regression was used to establish a six-gene prognostic model. LINC00278 expression was low in LSCC tissues, and it was significantly associated with the TNM (tumors/nodes/metastases) stage (p<0.001), lymphatic metastasis (p<0.01), and pathological differentiation (p<0.01). LINC00278 overexpression significantly reduced LSCC cell proliferation, migration, and invasion in TU686, TU177, and AMC-HN-8 cell lines. E-cadherin protein expression was increased, while N-cadherin, Vimentin, Zeb1, and Snail protein expression was decreased in the LINC00278 group, compared to the pcDNA3.1 group. Additionally, in AMC-HN-8 and FaDu cell lines, the LINC00278-treated group had significantly lower p-AKT and p-mTOR protein levels than the control group. ETS1 is a direct transcriptional regulator of the LINC00278 gene based on luciferase reporter assays and ChIP experiments. Western blot analysis demonstrated that high LINC00278 expression inhibited both ETS1 expression and phosphorylation. COL4A1/COL4A2 were identified as potential downstream targets of LINC00278. Meanwhile, the LINC00278/COL4A1/COL4A2-dominated low-risk group showed higher antigen-presenting activity and a higher immune score than the high-risk group. The findings indicated that ETS1 upregulated LINC00278 expression on the Y chromosome, which in turn inhibited LSCC growth in vivo and in vitro by inhibiting the AKT/mTOR signaling pathway via downregulation of COL4A1/COL4A2.

Long noncoding RNAs (lncRNAs) have an effect on the occurrence and progression of a considerable number of diseases, especially cancer. Existing research has suggested that MAGI2 antisense RNA 3 (MAGI2-AS3) takes on a critical significance in the development of hepatocellular carcinoma and lung cancer. However, the functions of MAGI2-AS3 in laryngeal squamous cell carcinoma (LSCC) remain unclear. In this study, MAGI2-AS3 expression level in LSCC tissue and cell lines was detected, and the effect of MAGI2-AS3 overexpressed on LSCC phenotypes and the possible influence mechanisms were examined. MAGI2-AS3 was downregulated in the tissues of LSCC patients versus non-tumor tissues, and it was correlated with advanced TNM (tumor, node, metastasis) stage and lymph node metastases, as indicated by the results of this study. MAGI2-AS3 inhibited the proliferation, migration, and invasion of LSCC cells in vitro and in vivo. Furthermore, the hypermethylation level of the MAGI2-AS3 promoter region was indicated by bisulfite genomic sequencing and methylation-specific polymerase chain reaction, such that MAGI2-AS3 expression was downregulated. Besides, MAGI2-AS3 promoter hypermethylation was regulated by DNA methyltransferase 1 (DNMT1), and MAGI2-AS3 expression was reversed by 5-Aza-2′-deoxycytidine (5-Aza). Moreover, the result of the RNA pull-down experiment suggested that 38 proteins were enriched in the MAGI2-AS3 group versus the control group in TU177 cells. To be specific, SPT6 (ie, a conserved protein) was enriched by fold change >10. SPT6 knockdown reduced the antitumor effect of MAGI2-AS3 in TU177 and AMC-HN-8 cells. Meanwhile, SPT6 overexpression inhibited the proliferation, metastasis, and invasion of TU177 and AMC-HN-8 cells. As revealed by the above findings, DNMT1-regulated MAGI2-AS3 promoter hypermethylation led to downregulated MAGI2-AS3 expression, such that the presence and progression of LSCC were inhibited in an SPT6 binding-dependent manner.

This study aims to elucidate the potential genes of the matrix metalloproteinase (MMP) family, responsible for the progression of laryngeal squamous cell carcinoma (LSCC). Besides, we ascertained the changes in common malignant behaviors in vitro by knocking down MMP1. TCGA, GEO, Oncomine, and Microarray data were conducted to analyze the expression levels of MMPs and to find tissue-specific genes in LSCC. Univariate and multivariate Cox regression analyses were established in the construction of a prognostic model based on expression profiles and clinical information of LSCC in TCGA. We then comprehensively analyzed survival, co-expression network, and immune infiltration based on a prognostic model by Kaplan-Meier analysis, WGCNA, and CIBERSORT. Thereafter, qRT-PCR, proliferation, Transwell, and wound healing assays were used to assess the accuracy of the bioinformatics data. A total of seven genes in the MMP family were identified as differentially expressed genes (DEGs) by integrating three public databases and microarray data. Additionally, multivariate Cox regression was used to establish a four-gene (MMP1/3/8/10) prognostic model, which exhibited a better predictive accuracy than the TNM (tumors/nodes/metastases) based model. The prognostic model was related to plasma cells, CD8+ T cells, follicular helper T cells, resting NK cells, and M0 macrophages infiltration. The expression of MMP1, MMP3, and MMP10 was the highest in head and neck squamous cell carcinoma (HNSC) compared to other cancer in the Oncomine and GEPIA dataset. Further, MMP1 demonstrated significant upregulation in 40 paired LSCC tissues. Eventually, MMP1 downregulation inhibited cell viability, colony formation, and cell migration in TU686 and FaDu cells. Our findings suggest that the four-gene signature might be associated with the prognos is. Further, we revealed that MMP1 is a pivotal biomarker for the biotherapy and prognostic evaluation of patients with LSCC.