Distributional comparison of different AAV vectors after unilateral cochlear administration.

The adeno-associated virus (AAV) gene therapy has been widely applied to mouse models for deafness. But, AAVs could transduce non-targeted organs after inner ear delivery due to their low cell-type specificity. This study compares transgene expression and biodistribution of AAV1, AAV2, Anc80L65, AAV9, AAV-PHP.B, and AAV-PHP.eB after round window membrane (RWM) injection in neonatal mice. The highest virus concentration was detected in the injected cochlea. AAV2, Anc80L65, AAV9, AAV-PHP.B, and AAV-PHP.eB transduced both inner hair cells (IHCs) and outer hair cells (OHCs) with high efficiency, while AAV1 transduced IHCs with high efficiency but OHCs with low efficiency. All AAV subtypes finitely transduced contralateral inner ear, brain, heart, and liver compared with the injected cochlea. In most brain regions, the enhanced green fluorescent protein (eGFP) expression of AAV1 and AAV2 was lower than that of other four subtypes. We suggested the cochlear aqueduct might be one of routes for vectors instantaneously infiltrating into the brain from the cochlea through a dye tracking test. In summary, our results provide available data for further investigating the biodistribution of vectors through local inner ear injection and afford a reference for selecting AAV serotypes for gene therapy toward deafness.

Luteolin inhibits the JAK/STAT pathway to alleviate auditory cell apoptosis of acquired sensorineural hearing loss based on network pharmacology, molecular docking, molecular dynamics simulation, and experiments in vitro.

PURPOSE: The study aimed to explore the mechanisms of luteolin in acquired sensorineural hearing loss (SNHL) through network pharmacology, molecular docking, molecular dynamics simulation, and experimental verification. METHODS: First, the practices of network pharmacology were used to obtain the intersecting targets of luteolin and acquired SNHL, construct the PPI (Protein-Protein Interaction) network, conduct GO and KEGG enrichments, and establish luteolin-acquired SNHL-target-pathway network, aiming to gain the core targets and pathways. Then, the affinity between the core targets and luteolin was verified by molecular docking. Moreover, molecular dynamics (MD) simulation was applied to simulate the binding between targets and luteolin. Finally, with the HEI-OC1 cell line, some molecular biology techniques were adopted to verify the pharmacological actions of luteolin and the significance of the pathway from KEGG enrichment in luteolin-protecting auditory cell damage related to acquired SNHL. RESULTS: 14 intersecting targets were obtained, and the 10 core targets were further verified through molecular docking and MD simulation to get 5 core targets. The JAK/STAT was selected as the critical pathway through KEGG enrichment. Luteolin could dose-dependently alleviate auditory cell apoptosis by inhibiting the JAK/STAT pathway, confirmed by a series of experiments in vitro. CONCLUSION: This study manifested that luteolin could reduce acquired SNHL-related auditory cell apoptosis through the JAK/STAT pathway, which provided a new idea for acquired SNHL pharmacological treatment.

Circ_0000052/miR-382-3p axis induces PD-L1 expression and regulates cell proliferation and immune evasion in head and neck squamous cell carcinoma.

A better understanding of the mechanisms underlying PD-L1 aberrant expression in head and neck squamous cell carcinoma (HNSCC) will help reveal predictive biomarkers and overcome resistance to treatment. In this study, the prognostic significance of PD-L1 in forty-five HNSCC archival samples was determined by qRT-PCR. The biological function associated with malignant behaviour was assessed by PD-L1 depletion, miR-382-3p re-expression and regulation of circ_0000052. The interactions of PD-L1-miRNA and miRNA-circRNA were determined by qRT-PCR, Western blot analysis, dual-luciferase reporter assays and RNA immunoprecipitation assays. PD-L1 was highly expressed in patient samples and cancer cell lines. Higher levels of PD-L1 were associated with patient recurrences and play a pivotal role in regulating cell proliferation, migration, invasion, clonogenicity and apoptosis. In addition to demonstrating that the IFN-γ/JAK2/STAT1 signalling pathway can induce PD-L1 overexpression in HNSCC, a novel mechanism by which upregulated circ_0000052 mediates PD-L1 overexpression was also demonstrated. To do this, circ_0000052 competitively binds to miR-382-3p and alleviates its repression of PD-L1. This leads to overexpression of PD-L1, causing the aggressiveness of the cells. Our data demonstrate that circ_0000052 is oncogenic, and the circ_0000052/miR-382-3p/PD-L1 axis is critical in HNSCC progression. The manipulation of circRNAs/miRNAs in combination with anti-PD-L1 therapy may improve personalized disease management.

The Diagnosis and Management of Advanced Endolymphatic Sac Tumor.

Endolymphatic sac tumor (ELST) is a group of low-grade malignant tumors originating from the endolymphatic sac of the inner ear. It is rare in the clinic and has the biological characteristics of slow growth and local aggression. Due to the lack of specificity in the clinical manifestations of patients with ELST, many cases have entered the advanced stage at the time of diagnosis. However, there are still great challenges in the treatment of advanced ELSTs. Here, the authors describe a case of advanced ELST, which relapsed after 2 operations. This time, the authors chose the transotic approach for tumor resection, which achieved the goal of complete resection of the tumor, and the patient recovered smoothly after surgery. There were no surgical complications and no tumor recurrence after the follow-up. Through literature review and our own experience, the authors suggest that complete surgical resection is the first choice for both primary and recurrent advanced ELSTs. The choice of a reasonable surgical approach is the key to ensuring complete resection of the tumor, while preoperative angiography and embolization, fine treatment of important structures during surgery, and postoperative long-term follow-up are equally important for patients with advanced ELST to obtain a good prognosis.

Erratum: Overexpression of lncRNA H19/miR-675 promotes tumorigenesis in head and neck squamous cell carcinoma: Erratum.

[This corrects the article DOI: 10.7150/ijms.16571.].

Cochlear Implantation in a Patient with Neurofibromatosis Type 2 and an Intracochlear Schwannoma: A Case Report and Literature Review.

A primary intracochlear schwannoma (ICS) is a unique type of vestibular schwannoma (VS); the tumor originates from the terminal branches of the cochlear nerve and is confined to the cochlea. An ICS is the most common subtype of schwannoma in the inner ear. As an ICS is clinically rare, diagnosis and treatment remain challenging. We report a rare case of cochlear implantation (CI) in a patient with neurofibromatosis type 2 and an ICS. The patient exhibited bilateral, profound, sensorineural hearing loss. The tumor on one side was a common VS treated via tumor and acoustic nerve resection and that on the other side an ICS. To ensure auditory rehabilitation via CI, we performed CI while removing part of the ICS via an enlarged round window. Auditory rehabilitation was satisfactory. Thus, ICS patients, especially those who urgently require auditory rehabilitation, can undergo simultaneous CI and (total or partial) tumor removal. However, the long-term results require close observation.

Total Resection of Cerebellopontine Angle Meningioma via Presigmoid Transmastoid Approach: An Otologist's Perspective.

PURPOSE: Cerebellopontine angle meningiomas (CPAMs) are benign tumors that arise from the dura mater of the petrosal surface of the temporal bone, lateral to the trigeminal nerve. This study aimed to describe 1 case of CPAMs violating the mastoid and highlight the unique superiority of the presigmoid transmastoid approach for this type of CPAMs from an otologist's perspective. METHODS: One case of specific CPAMs treated by total resection via presigmoid transmastoid approach in otomicrosurgery was described. RESULTS: A patient was referred for the left intracranial space-occupying lesion found in physical examination. Surgical resection via presigmoid transmastoid approach was performed and there was no sign of recurrence of tumor 2 years after the operation. CONCLUSIONS: Presigmoid transmastoid approach in otomicrosurgery is suitable for CPAMs invading the mastoid. It is suggested that neurosurgeons and ear surgeons should comprehensively analyze the type and extent of the tumor and flexibly adopt surgical methods to ensure it is the best for patients.

Retracted: Mukonal Inhibits Cell Proliferation, Alters Mitochondrial Membrane Potential and Induces Apoptosis and Autophagy in Human CNE1 Nasopharyngeal Carcinoma Cells.

Retracted, due to breach of publishing guidelines, following the identification of non-original content. Reference: Mukonal Inhibits Cell Proliferation, Alters Mitochondrial Membrane Potential and Induces Apoptosis and Autophagy in Human CNE1 Nasopharyngeal Carcinoma Cells Yingyuan Guo, Yanru Hao, Guofang Guan, Shuaishuai Ma, Zhiling Zhu, Fang Guo, Jie Bai Med Sci Monit 2019; 25:1976-1983 10.12659/MSM.913915.

A Case of Atypical Skull Base Osteomyelitis Secondary to Otitis Media Due to Delayed Diagnosis.

ABSTRACT: Skull base osteomyelitis that is secondary to otitis media is extremely rare in the modern antibiotic era. The authors present an 84-year-old male with atypical skull base osteomyelitis that developed from otitis media during the COVID-19 pandemic due to delayed diagnosis and partial treatment which is blamed for development of skull base osteomyelitis. The atypical presentations of skull base osteomyelitis pose a diagnostic challenge. This case highlights that even otitis media is a potentially fatal infection in older patients with diabetes. Early diagnosis and aggressive management of skull base osteomyelitis are of upmost importance and will ensure a more favorable prognosis.

A Rare Instance of Primary Oncocytic Schneiderian Papilloma of Middle Ear and Eustachian Tube With a Combined Trans Oto and Nasal Approach Resection.

Oncocytic Schneiderian papillomas are rare tumours which usually arise in the sinonasal region. This paper presents, to the authors' knowledge, the first reported case of oncocytic Schneiderian papilloma arising primarily from the middle ear and eustachian tube. The resection of the tumor was performed with an endoscopic approach of combined trans oto and nasal. Oncocytic Schneiderian papilloma in the middle ear and eustachian tube is extremely rare as a primary lesion and challenging to manage. Very few documents have provided guide of resection using the endoscopic approach when this tumor extends to involve the eustachian tube. Our study illustrates that the endoscopic approach of combined trans oto and nasal is a good choice for tumor resection of middle ear and eustachian tube.

Mukonal Inhibits Cell Proliferation, Alters Mitochondrial Membrane Potential and Induces Apoptosis and Autophagy in Human CNE1 Nasopharyngeal Carcinoma Cells.

BACKGROUND Nasopharyngeal carcinoma results in high patient morbidity and mortality, due to early metastasis, and toxicity due to chemotherapy. Mukonal is plant-derived carbazole alkaloid that has been used in traditional Chinese medicine to treat several types of cancer. This study aimed to investigate the effects of mukonal on cell proliferation, apoptosis, autophagy, and the mitochondrial membrane potential of nasopharyngeal carcinoma cells in vitro. MATERIAL AND METHODS CNE1 human nasopharyngeal carcinoma cells and NP69 normal nasopharyngeal epithelial cells were cultured with and without treatment with increasing doses of mukonal. Cell viability was determined by the MTT assay. Fluorescence microscopy was used to detect reactive oxygen species (ROS), mitochondrial membrane potential, and the release of cytochrome C. Flow cytometry was used to examine changes in the cell cycle, electron microscopy examined cell autophagy, and Western blot was performed to measure levels of proteins associated with autophagy and apoptosis. RESULTS Mukonal had an antiproliferative effect on CNE1 cells, with an IC50 of 9 µM and there were effects of toxicity on normal NP69 cells. Mukonal triggered ROS-mediated changes in mitochondrial membrane potential which was also accompanied by the discharge of cytochrome C in the CNE1 cells. Mukonal activated autophagy and apoptosis in CNE1 cells, which was also associated with upregulation of the autophagy-related proteins, LC3 II and beclin-1, as well as apoptosis-associated proteins, Bax, cleaved caspase-3 and -9. Mukonal treatment also resulted in CNE1 cells cycle arrest at G2/M. CONCLUSIONS Mukonal inhibited the growth of human CNE1 nasopharyngeal carcinoma cells in vitro.

Expression of RNA-binding motif 10 is associated with advanced tumor stage and malignant behaviors of lung adenocarcinoma cancer cells.

This study assessed RNA-binding motif 10 expression in lung adenocarcinoma tissues and examined the role and mechanism of RNA-binding motif 10 in the regulation of lung adenocarcinoma malignancy. Lung adenocarcinoma and corresponding adjacent non-tumor lung tissues from 41 patients were subjected to reverse transcription-polymerase chain reaction and Western blot assessment to detect RNA-binding motif 10 expression. Recombinant lentivirus carrying RNA-binding motif 10 complementary DNA was used to infect lung adenocarcinoma cell lines, A549 and H1299 cells. Complementary DNA microarray was used to profile RNA-binding motif 10-regulated genes. Levels of RNA-binding motif 10 messenger RNA and protein were significantly lower in lung adenocarcinoma tissues than those in paired non-tumor tissues (p < 0.001). Reduced RNA-binding motif 10 expression was found to be associated with an advanced tumor stage. RNA-binding motif 10 overexpression inhibited viability and colony formation capacity of lung adenocarcinoma cell lines and induced cell-cycle arrest at G0/G1 phase in A549 cells and at S phase in H1299 cells. Complementary DNA microarray analysis identified 304 upregulated and 386 downregulated genes induced by RNA-binding motif 10 overexpression, which may be involved in cancer, focal adhesion, peroxisome proliferator-activated receptor-regulated gene pathway, cytokine-cytokine receptor interaction, mitogen-activated protein kinase signaling, complement and coagulation cascades, platelet amyloid precursor protein pathway, extracellular matrix-receptor interaction, and small cell lung cancer-related genes. Expression of FGF2, EGFR, WNT5A, NF-κB, and RAP1A was downregulated, whereas expression of AKT2, BIRC3, and JUN was upregulated. RNA-binding motif 10 messenger RNA and protein were reduced in lung adenocarcinoma tissues, and RNA-binding motif 10 overexpression inhibited lung adenocarcinoma cancer cell malignant behavior in vitro. Molecularly, RNA-binding motif 10 regulates many gene pathways involving in the tumor development or progression.

Overexpression of lncRNA H19/miR-675 promotes tumorigenesis in head and neck squamous cell carcinoma.

There is accumulating evidence indicating that long non-coding RNA H19 and its mature product miR-675 play essential roles for tumor growth and progression. However, their prognostic value in human head and neck squamous cell carcinoma (HNSCC), particular in laryngeal carcinoma, remains to be elucidated. In this study, we observed that both H19 and miR-675 were significantly overexpressed in a cohort of 65 primary tumor samples and two HNSCC cell lines. Importantly, when paired with patient follow-up data, higher expression of either H19 or miR-675 was significantly correlated with higher risk of patient relapse, and associated with worse overall survival and poor disease-free survival. Knockdown miR-675 caused significant reduction of cell viability, migratory and invasive capabilities. Taken together, these results suggest that the strong correlation of H19 overexpression together with higher miR-675 and lymph node metastases could be useful predictive markers, indicating a potentially therapeutic strategy for HNSCC patients.

Constitutive secretion of Interleukin-4 dictates CD133+ side population cells to resist drug treatment and cell death.

PURPOSE: In the present study, we made an attempt to elucidate the role of oversecretion of interleukin-4 (IL-4) in cancer stem cells (CSCs) of head and neck squamous cell carcinoma (HNSCC). METHODS: HNSCC samples were analyzed for the presence of CSCs by flow cytometry. In addition, we have performed drug and apoptosis resistance assays to determine the role of IL-4 in CSCs. RESULTS: HNSCC samples contained 3.3% of CD133+ cancer stem like side population (SP) cells in HNSCC which displayed infinite cell proliferation and they had high self-renewal capacity. These CD133+ cells displayed enhanced expression of IL-4, which promoted multidrug and apoptosis resistance. After neutralizing IL-4, the CD133+ SP cells became more sensitive to drug treatment and apoptosis. CONCLUSIONS: Our data suggest that the autocrine secretion of IL-4 is a potential target for the development of novel anticancer drugs to prevent the CSCs-mediated therapy failure and tumorigenesis.

Salmonella typhimurium mediated delivery of Apoptin in human laryngeal cancer.

An effective cancer therapeutic should target tumours specifically with limited systemic toxicity. Here, we transformed an attenuated Salmonella typhimurium (S. typhimurium) with an Apoptin expressing plasmid into a human laryngeal carcinoma cell line. The expression of the inserted gene was measured using fluorescence and immunoblotting assays. The attenuated S. typhimurium-mediated Apoptin significantly decreased cytotoxicity and strongly increased cell apoptosis through the activation of caspase-3. The process was mediated by Bax, cytochrome c and caspase-9. A syngeneic nude murine tumour model was used to determine the anti-tumour effects of the recombinant bacteria in vivo. Systemic injection of the recombinant bacteria with and without re-dosing caused significant tumour growth delay and reduced tumour microvessel density, thereby extending host survival. Our findings indicated that the use of recombinant Salmonella typhimurium as an Apoptin expression vector has potential cancer therapeutic benefits.

Low-grade fibromyxoid sarcoma in the middle ear as a rare location: a case report.

Background: Low-grade fibromyxoid sarcoma (LGFMS) is a rare soft tissue tumor with a misleadingly bland histological appearance and fully malignant behavior, typically occurring in the deep soft tissues of the proximal extremities or trunk of young adults. However, no cases of primary middle ear LGFMS have been reported previously. LGFMS is characterized by high rates of local recurrence and metastatic spread, which should be attached of great importance to clinical diagnosis and treatment. Case Description: Herein, we report an unusual case of LGFMS occurring primarily in the middle ear of a 12-year-old boy, who presented with aural fullness and gradually progressive hearing loss in the left ear for 6 months, without other related symptoms and family history. Preoperative imaging examination suggested that the lesions were located in the tympanic cavity, tympanic antrum, and mastoid portion, with equisignal or hypointense on T1 weighted image (T1WI), apparent hyperintense on T2 weighted image (T2WI), and slight enhancement on T1WI following administration of gadolinium. A decision was made to perform mastoidectomy, as the lesion was limited to the middle ear and did not invade the facial nerve canal or the inner ear. During the surgery, the mass exhibited a hard texture and smooth surface that was approximately 1.0 cm × 1.5 cm in size, not easy to bleed, and non-adherent to surrounding tissues. After consultation, a diagnosis of LGFMS was made by postoperative pathology. The patient showed an excellent recovery from surgery without any complications. At present, the patient has been followed up for 24 months, and no local recurrence or distant metastasis has been observed. Conclusions: The primary LGFMS in the middle ear is very rare, and the clinical manifestations and related examinations lack specificity, so a clinical diagnosis of LGFMS is very difficult, and the final diagnosis is mainly determined by pathological diagnosis. Due to its malignant behavior, clinical diagnosis and treatment should be vigilant against it. Treatment of LGFMS mainly requires extensive resection combined with radiotherapy and chemotherapy if necessary, and long-term follow-up is essential. Reporting and identification of this rare case are imperative to improving our understanding of LGFMS and reducing misdiagnosis.

Expression of PD-L1 and CD4+ tumor-infiltrating lymphocytes predict survival in head and neck squamous cell carcinoma.

The clinical efficacy of immune checkpoint blockade has been recently demonstrated in a variety of cancer types. The aim of the present study was to characterize the expression profile of tumor-infiltrating lymphocytes (TILs) and programmed death-ligand 1 (PD-L1) in head and neck squamous carcinoma (HNSCC). A total of 63 patients with HNSCC were enrolled in the present study. CD3+ and CD4+ TILs and the expression of PD-L1 were detected by immunohistochemistry. PD-L1 mRNA levels were evaluated by reverse transcription-quantitative PCR analysis. The association of TILs and PD-L1 with patient clinicopathological characteristics was also assessed. CD3+ and CD4+ TILs were detected in 100% of the samples. CD3+ was the predominant subset of TILs. PD-L1 was expressed in 53 of 61 (86%) patients when a score of ≥1 on tumor cells was considered positive and in 28 patients (45.2%) when a score of >5 on tumor cells was considered positive. PD-L1 mRNA levels were determined to be significantly correlated with PD-L1 protein expression. Survival analysis demonstrated that high CD4+ TILs were associated with improved overall survival (OS) and disease-free survival (DFS), and furthermore, the association of high PD-L1 expression with unfavorable OS and DFS was statistically significant. Multivariate analysis identified CD4+ TILs and PD-L1 as prognostic markers for HNSCC. The results of the present study suggested that increased CD4+ TILs in HNSCC may be associated with improved outcomes, while high expression of PD-L1 may indicate unfavorable OS and DFS; thus, these factors may serve as predictors of the response to immune checkpoint therapy.

Prevalence and Characteristics of STRC Gene Mutations (DFNB16): A Systematic Review and Meta-Analysis.

Background: Mutations in the STRC (MIM 606440) gene, inducing DFNB16, are considered a major cause of mild-moderate autosomal recessive non-syndromic hearing loss (ARNSHL). We conducted a systematic review and meta-analysis to determine the global prevalence and characteristics of STRC variations, important information required for genetic counseling. Methods: PubMed, Google Scholar, Medline, Embase, and Web of Science were searched for relevant articles published before January 2021. Results: The pooled prevalence of DFNB16 in GJB2-negative patients with hearing loss was 4.08% (95% CI: 0.0289-0.0573), and the proportion of STRC variants in the mild-moderate hearing loss group was 14.36%. Monoallelic mutations of STRC were 4.84% (95% CI: 0.0343-0.0680) in patients with deafness (non-GJB2) and 1.36% (95% CI: 0.0025-0.0696) in people with normal hearing. The DFNB16 prevalence in genetically confirmed patients (non-GJB2) was 11.10% (95% CI: 0.0716-0.1682). Overall pooled prevalence of deafness-infertility syndrome (DIS) was 36.75% (95% CI: 0.2122-0.5563) in DFNB16. The prevalence of biallelic deletions in STRC gene mutations was 70.85% (95% CI: 0.5824-0.8213). Conclusion: Variants in the STRC gene significantly contribute to mild-moderate hearing impairment. Moreover, biallelic deletions are a main feature of STRC mutations. Copy number variations associated with infertility should be seriously considered when investigating DFNB16.

A novel missense mutation in SMPX causes a rare form of X-linked postlingual sensorineural hearing loss in a Chinese family.

BACKGROUND: X-linked deafness-4 (DFNX4) caused by the functional loss of the SMPX gene is one form of nonsyndromic hearing loss with postlingual onset. This study aimed to investigate the cause of X-linked inherited sensorineural nonsyndromic hearing loss in a four-generation Chinese family and to explain the reason for extremely different hearing phenotypes between the proband and other family members. METHODS: Whole-exome sequencing (WES) and co-segregation analysis were used to identify the pathogenic variants. Furthermore, methylation differences among the androgen receptor genes were utilized to investigate whether the severe phenotype of the proband is related to X-chromosome inactivation (Xi). RESULTS: We described in detail the clinical characteristics of the family and identified a novel missense mutation (c.262C>G: p.Gln88Glu) in SMPX by WES. This variant was co-segregated with the postlingual hearing loss phenotype and was absent in 300 normal controls. Also, we found that the proband, a 4-year-old female, carries two new compound heterozygous mutations (c.9259G>A: p.Val3087Ile and c.8576G>A: p.Arg2859His) in the USH2A gene, but to date without any other symptoms except profound sensorineural hearing loss. Additionally, analysis of X-chromosome inactivation indicated moderate skewing in the proband, which is probably related to the heterogeneity of clinical characteristics. CONCLUSIONS: This is the first study to report a missense mutation of SMPX in a Chinese family. Our findings have enriched the mutation and phenotypic spectrum of the SMPX gene.

Identifying the mechanisms underlying the protective effect of tetramethylpyrazine against cisplatin­induced in vitro ototoxicity in HEI­OC1 auditory cells using gene expression profiling.

Sensorineural hearing loss is prevalent in patients receiving cisplatin therapy. Tetramethylpyrazine (Tet) and tanshinone IIA (Tan IIA) have protective roles against hearing impairment or ototoxicity. The present study aimed to investigate the molecular mechanisms underlying cisplatin­induced ototoxicity and the protective effect of Tet and Tan IIA against it. House Ear Institute­Organ of Corti 1 auditory cells were treated with titrating doses of Tan IIA, Tet, and cisplatin. In a cell viability assay, cisplatin, Tan IIA and Tet had IC50 values of 42.89 µM, 151.80 and 1.04x103 mg/l, respectively. Tan IIA augmented cisplatin­induced cytotoxicity. However, Tet concentrations <75 mg/l attenuated cisplatin­induced cytotoxicity and apoptosis. Moreover, RNA sequencing analysis was carried out on auditory cells treated for 30 h with 30 µM cisplatin alone for 48 h or combined with 37.5 mg/l Tet for 30 h. Differentially expressed genes (DEGs) induced in these conditions were identified and examined using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis. Cisplatin increased the expression of genes related to the p53 and FoxO pathways, such as Fas, p21/CDKN1A, and Bcl­2 binding component 3, but decreased the expression of insulin­like growth factor 1 (IGF1), as well as genes in the histone (Hist)1 and Hist2 clusters. Treatment with Tet downregulated FOXO3 and Bcl­2 binding component 3, and increased the expression of IGF1. Moreover, Tet upregulated genes associated with Wnt signaling, but not p53­related genes. Thus, the otoprotective properties of Tet might be mediated by activation of Wnt and IGF1 signaling, and inhibition of FoxO signaling.