KLF7 regulates super-enhancer-driven IGF2BP2 overexpression to promote the progression of head and neck squamous cell carcinoma.

BACKGROUND: Head and neck squamous carcinoma (HNSCC) is known for its high aggressiveness and susceptibility to cervical lymph node metastasis, which greatly contributes to its poor prognosis. During tumorigenesis, many types of cancer cells acquire oncogenic super-enhancers (SEs) that drive the overexpression of oncogenes, thereby maintaining malignant progression. This study aimed to identify and validate the role of oncogenic SE-associated genes in the malignant progression of HNSCC. METHODS: We identified HNSCC cell-specific SE-associated genes through H3K27Ac ChIP-seq and overlapped them with HNSCC-associated genes obtained from The Cancer Genome Atlas (TCGA) dataset and Gene Expression Omnibus (GEO) datasets using weighted gene coexpression network analysis (WGCNA) to identify hub genes. The expression of IGF2BP2 and KLF7 in HNSCC was detected using clinical samples. To determine the biological role of IGF2BP2, we performed CCK-8, colony formation assay, Transwell migration assay, invasion assay, and orthotopic xenograft model experiments. Furthermore, we utilized a CRISPR/Cas9 gene-editing system, small-molecule inhibitors, ChIP-qPCR, and dual-luciferase reporter assays to investigate the molecular mechanisms of IGF2BP2 and its upstream transcription factors. RESULTS: Our study identified IGF2BP2 as a hub SE-associated gene that exhibited aberrant expression in HNSCC tissues. Increased expression of IGF2BP2 was observed to be linked with malignant progression and unfavorable prognosis in HNSCC patients. Both in vitro and in vivo experiments confirmed that IGF2BP2 promotes the tumorigenicity and metastasis of HNSCC by promoting cell proliferation, migration, and invasion. Mechanistically, the IGF2BP2-SE region displayed enrichment for H3K27Ac, BRD4, and MED1, which led to the inhibition of IGF2BP2 transcription and expression through deactivation of the SE-associated transcriptional program. Additionally, KLF7 was found to induce the transcription of IGF2BP2 and directly bind to its promoter and SE regions. Moreover, the abundance of KLF7 exhibited a positive correlation with the abundance of IGF2BP2 in HNSCC. Patients with high expression of both KLF7 and IGF2BP2 showed poorer prognosis. Lastly, we demonstrated that the small molecule inhibitor JQ1, targeting BRD4, attenuated the proliferation and metastatic abilities of HNSCC cells. CONCLUSIONS: Our study reveals the critical role of IGF2BP2 overexpression mediated by SE and KLF7 in promoting HNSCC progression. Targeting SE-associated transcriptional programs may represent a potential therapeutic strategy in managing HNSCC.

FTO Sensitizes Oral Squamous Cell Carcinoma to Ferroptosis via Suppressing ACSL3 and GPX4.

Ferroptosis is a newly established form of regulated cell death characterized by intracellular lipid peroxidation and iron accumulation that may be a promising cancer treatment strategy. However, the function and therapeutic value of ferroptosis in oral squamous cell carcinoma (OSCC) remain inadequately understood. In the present study, we investigated the biological role of the fat mass and obesity-associated gene (FTO) in ferroptosis in the context of OSCC. We found that OSCC had greater potential for ferroptosis, and FTO is associated with ferroptosis. Furthermore, higher FTO expression sensitized OSCC cells to ferroptosis in vitro and in vivo. Mechanistically, FTO suppressed the expression of anti-ferroptotic factors, acyl-CoA synthetase long-chain family member 3 (ACSL3) and glutathione peroxidase 4 (GPX4), by demethylating the m6A modification on the mRNA of ACSL3 and GPX4 and decreasing their stability. Taken together, our findings revealed that FTO promotes ferroptosis through ACSL3 and GPX4 regulation. Thus, ferroptosis activation in OSCC with high FTO levels may serve as a potential therapeutic target.

Identification of CKS2 as a novel prognostic biomarker and potential therapeutic target for oral squamous cell carcinoma.

Background: The cyclin-dependent kinase subunit 2 (CKS2) is recognized to have a substantial impact on the pathogenesis and advancement of several malignant neoplasms. Nevertheless, its biological function and prognostic significance in oral squamous cell carcinoma (OSCC) have yet to be thoroughly investigated. Our primary objective was to clarify the contribution of CKS2 in the progression and prognosis of OSCC. Methods: We first conducted a thorough examination of online databases to investigate the expression of CKS2, and subsequently corroborated our discoveries by analyzing clinical specimens that we collected. According to the clinicopathological data, we then explored the prognostic significance of CKS2. Furthermore, we predicted the role of CKS2 in OSCC progression by employing weighted gene co-expression network analysis (WGCNA) in conjunction with functional enrichment analysis. We conducted functional experiments in vitro to confirm our speculations. Additionally, we explored other potential functions of CKS2 in immune infiltration, tumor mutation burden (TMB), and drug sensitivity. Finally, we established and validated a nomogram that effectively integrated CKS2-related genes and other relevant clinical factors. Results: Our findings indicated a significant upregulation of CKS2 expression in OSCC tissues compared to normal groups, which was positively associated with poor clinical outcomes. We also predicted and validated the role of CKS2 in promoting proliferation by regulating the cell cycle. Additionally, its upregulation was significantly correlated to enhanced immune cell infiltration, high TMB, and increased sensitivity of anti-tumor agents. Following verification, the nomogram was conducted to quantify an individual's survival probability. Conclusions: In general, our study indicates that CKS2 is a novel prognostic biomarker and potential therapeutic target in OSCC.

METTL14 inhibits malignant progression of oral squamous cell carcinoma by targeting the autophagy-related gene RB1CC1 in an m6A-IGF2BP2-dependent manner.

N6-methyladenosine (m6A) plays crucial roles in tumorigenesis and autophagy. However, the underlying mechanisms mediated by m6A and autophagy in the malignant progression of oral squamous cell carcinoma (OSCC) remain unclear. In the present study, we revealed that down-regulated expression of METTL14 was correlated with advanced clinicopathological characteristics and poor prognosis in OSCC. METTL14 knockdown significantly inhibited autophagy and facilitated malignant progression in vitro, and promoted tumor growth and metastasis in vivo. A cell model of rapamycin-induced autophagy was established to identify RB1CC1 as a potential target gene involved in m6A-regulated autophagy in OSCC, through RNA sequencing and methylated RNA immunoprecipitation sequencing (meRIP-seq) analysis. Mechanistically, we confirmed that METTL14 posttranscriptionally enhanced RB1CC1 expression in an m6A-IGF2BP2-dependent manner, thereby affecting autophagy and progression in OSCC, through methylated RNA immunoprecipitation qRT-PCR (meRIP-qPCR), RNA stability assays, mutagenesis assays and dual-luciferase reporter. Collectively, our findings demonstrated that METTL14 serves as an OSCC suppressor by regulating the autophagy-related gene RB1CC1 through m6A modification, which may provide a new insight for the diagnosis and therapy of OSCC.

Integrative Analysis of N6-Methyladenosine-Related Enhancer RNAs Identifies Distinct Prognosis and Tumor Immune Micro-Environment Patterns in Head and Neck Squamous Cell Carcinoma.

At present, the prognostic value of N6-methyladenosine (m6A)-related enhancer RNAs (eRNAs) for head and neck squamous cell carcinoma (HNSCC) still remains unclear. Our study aims to explore the prognostic value of m6A-related eRNAs in HNSCC patients and their potential significance in immune infiltration and immunotherapy. We constructed a 5 m6A-related eRNAs risk model from The Cancer Genome Atlas (TCGA) HNSCC dataset, using univariate and multivariate Cox and least absolute shrinkage and selection operator (LASSO) regression analysis. Based on the SRAMP website and in vitro experiments, it was verified that these 5 m6A-related eRNAs had m6A sites, the expression of which was regulated by corresponding m6A regulators. Moreover, we constructed a nomogram base on 5 m6A-related eRNAs and confirmed the consistency and robustness of an internal TCGA testing set. Further analysis found that the risk score was positively associated with low overall survival (OS), tumor cell metastasis, metabolic reprogramming, low immune surveillance, lower expression of immune-related genes, and higher expression of targeted genes. Finally, we verified that silencing MIR4435-2HG inhibited HNSCC cell migration and invasion. This study contributes to the understanding of the characteristics of m6A-related eRNAs in HNSCC and provides a reference for effective immunotherapy and targeted therapy.

The systemic inflammation response index predicts the survival of patients with clinical T1-2N0 oral squamous cell carcinoma.

OBJECTIVE: The systemic inflammation response index (SIRI) is an independent prognostic factor for many malignant tumors. However, the value of this factor in patients with clinical T1-2N0 (cT1-2N0) oral squamous cell carcinoma (OSCC) is still unclear. METHODS: We calculated SIRI of 235 cT1-2N0 OSCC patients from 2013 to 2017. Multivariate cox regression analysis was applied to verify the prognostic significance of SIRI. Kaplan-Meier curves were plotted to analyze the overall survival (OS) and disease-specific survival (DSS) for cT1-2N0 OSCC patients. RESULTS: According to the optimal cutoff point of SIRI, we divided cT1-2N0 OSCC patients into high SIRI group (SIRI ≥ 1.3) and low SIRI group (SIRI < 1.3). SIRI was an independent prognostic indicator for OS (HR = 2.87; 95% CI = 1.35-6.10; p = .006) and DSS (HR = 2.17; 95% CI = 1.10-4.27; p = .025). High SIRI had a significantly poorer OS (p = .001) and DSS (p = .007) in survival analysis than the low SIRI. Moreover, the prognostic value of SIRI was significantly stronger than neutrophil-to-lymphocyte ratio (NLR) and monocyte-to-lymphocyte ratio (MLR). CONCLUSIONS: Preoperative SIRI can be regarded as a meaningful indicator for poor survival of cT1-2N0 OSCC patients, and it is a promising tool to formulate the best individualized treatment for high-risk patients.