Methylation status of SFRP1, SFRP2, RASSF1A, RARβ and DAPK1 genes in patients with oral squamous cell carcinoma

The association between DNA methylation status and Epstein-Barr virus infection in laryngeal carcinomas

INTRODUCTION

Infection with Epstein-Barr virus is a known risk factor for laryngeal carcinogenesis; it might influence DNA methylation acting as an epigenetic driver in this type of malignancy.

METHODS

Paired laryngeal tissues (neoplastic and peri-neoplastic) harvested from 24 patients were included in the study. Eleven patients expressing latent/lytic EBV genes were considered positive. 5-mC% was determined using ELISA technique and TSGs (PDLIM4, WIF1, DAPK1) promoters' methylation percentages were quantified by qMS-PCR. DNMTs (DNMT1 and DNMT3B) expression levels were quantified in qRT-PCR.

RESULTS

Overall, in laryngeal neoplastic samples vs peri-neoplastic ones, lower 5mC% (p=0.004) and higher TSGs promoters hypermethylation were found (p<0.0001). Significant correlation between PDLIM4 and DAPK1 promoter methylation and 5-mC% (PDLIM4 p=0.0186; DAPK1 p=0.0259) was noted. Higher 5-mC% (p=0.0041), lower PDLIM4 gene promoter methylation (p=0.0017) and overexpression of DNMTs (DNMT1: p=0.0018, respectively DNMT3B: p=0.0017) were associated with EBV infection. Also, significant differences between EBV-positive and EBV-negative cases based on tumor stage (T) were noted for 5mC% in both T1/T2 (p=0.0364) and T3/T4 stages (p=0.0275), and for PDLIM4 promoter methylation in T1/T2 stages (p=0.0121).

CONCLUSION

Future studies are needed to more effectively illustrate the interplay between EBV infection and these epigenetic mechanisms. Notably, our study highlighted a correlation between EBV and epigenetic changes in laryngeal carcinoma.

Immunohistochemical Expression of DAPK-1 in Oral Leukoplakia And Oral Squamous Cell Carcinoma: A Preliminary Study

INTRODUCTION

The silencing of death-associated protein kinase 1 (DAPK-1) is an effective way of inactivating a tumor-suppressing mechanism. The aim of this study was to investigate the immunohistochemical expression of DAPK-1 in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC).

METHODS

The immunohistochemical (IHC) detection of DAPK-1 was carried out in cases of OLs and OSCCs. DAPK-1 molecules' tissue distribution in OLs/OSCCs tissues was evaluated using semiquantitative immunohistochemistry in representative paraffin-embedded tissue samples (57 in total) from 2004-2019, retrieved from the archives of the Department of Oral Medicine/Pathology, School of Dentistry, Aristotle University of Thessaloniki, Greece and the St Lukas Hospital of Thessaloniki, Greece. The inclusion criterion was the presence of sufficient precancerous or cancerous biological material (estimated as more than 70% per tissue specimen) in the paraffin cubes. The exclusion criterion was the opposite, i.e. the lack of sufficient material due to previous sections. Statistics for IHC were evaluated by a non-parametric Mann-Whitney U Test. A two-sided p-value < 0.05 was considered statistically significant.

RESULTS

DAPK-1 IHC expression was increased in OLs without dysplasia and with OLs with mild dysplasia compared to moderate/severe dysplasia (p=0.019, Mann-Whitney U Test) and OSCCs (p=0.003, Mann-Whitney U Test).  Conclusions: DAPK-1 seemed to function as an oncosuppressor molecular biomarker, as its expression was decreased in areas of cellular dysplasia in OLs and in areas of OSCCs composed of less differentiated cells. The clinical application of this biomarker is that the positively stained, potentially malignant lesions are less likely to transition into malignancy, and cancerous lesions are more likely to behave non-aggressively. On the other hand, the lack of staining could signify the loss of this oncosuppressing ability, and it could be a potential prognostic biomarker for OSCC's aggressive biologic behavior if considered with other clinical parameters and a prognostic factor of malignant transformation of potentially malignant lesions. Since this is a preliminary study, more studies with larger sample sizes are required to support these conclusions.

Expression, prognosis, immunological infiltration, and DNA methylation of members of the SFRP gene family in colorectal cancer: a comparative bioinformatic and experimental analysis

This study aimed to investigate the expression, prognostic significance, methylation, and immune invasion levels of secreted frizzled-related proteins (SFRP1-5) in colorectal cancer (CRC). Additionally, the relationship between SFRP1/2 methylation and immune infiltration in CRC was explored. The expression of SFRP1-5 was analyzed using several databases, including GEO, TCGA, TIMER, STRING, and GEPIA. Molecular interactions with SFRPs were examined via Cytoscape software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes, and Genomes (KEGG) pathway analyses were conducted using the DAVID database. Methylation levels of SFRP1/2 in CRC were assessed through methylation-specific PCR (MSP) and bisulfite sequencing PCR (BSP) experiments. Apoptosis and proliferation in CRC cells following the knockdown of SFRP1/2 expression were evaluated using flow cytometry and CCK-8 assays. The TISIDB database was used to analyze the relationship between SFRP1/2 methylation levels and immune infiltration. The expression of SFRP1, SFRP2, and SFRP5 was significantly lower in CRC patients, while SFRP4 expression was higher compared to that in healthy individuals. Elevated mRNA expression of SFRP2 was significantly associated with improved overall survival (OS), disease-specific survival, and progression-free intervals. SFRP1/2 expression was also linked to immune invasion, with higher levels correlating with increased immune infiltration. Both SFRP1 and SFRP2 showed hypermethylation in CRC. Knockdown of SFRP1/2 expression resulted in increased proliferation of CRC cells, and their methylation levels were inversely correlated with immune cell presence. The expression, methylation, and immune cell infiltration patterns of the SFRP family in CRC differed markedly from those in healthy individuals. These findings suggest that SFRPs may serve as potential therapeutic targets and key genes associated with immune cell infiltration in CRC.

DNA hypermethylation of tumor suppressor genes among oral squamous cell carcinoma patients: a prominent diagnostic biomarker

Oral Squamous Cell Carcinoma is a globally revealing form of oral malignancy. Epigenetics, which studies genetic modifications in gene expression without altering the sequence of DNA, is crucial for understanding OSCC. Key epigenetic modifications such as histone modifications, DNA methylation, and microRNA regulation play significant roles in Oral carcinoma. Aberrant methylation of DNA of tumor suppressor genes which leads to their inactivation, promoting cancer development, and specific methylation patterns are emerging as biomarkers for early OSCC detection.Current treatments like surgery, radiotherapy, and chemotherapy often fall short, prompting research into epigenetic therapies. Agents like DNMT and HDAC inhibitors demonstrate the potential for reversing aberrant epigenetic patterns, perhaps reactivating silenced TSGs, and suppressing oncogenes. Despite early promise, the development of effective combination medicines and the identification of reliable biomarkers continue to present challenges.In OSCC, resistance to therapy is also influenced by epigenetic processes. Aberrant DNA methylation and changes in histone modifications impact genes involved in medication metabolism and the survival of cells. Enhancing treatment efficacy and overcoming medication resistance may be possible by recognizing and focusing on these processes. This review explores the interplay between epigenetic changes and OSCC, their role in the disease's initiation and progression, and their impact on diagnosis and treatment. It also discusses the potential of epigenetic drugs (epi-drugs) to improve diagnostic precision and treatment outcomes.

HOXA1 3'UTR Methylation Is a Potential Prognostic Biomarker in Oral Squamous cell Carcinoma

BACKGROUND

HOXA1 is a prognostic marker and a potential predictive biomarker for radioresistance in head and neck tumors. Its overexpression has been associated with promoter methylation and a worse prognosis in oral squamous cell carcinoma (OSCC) patients. However, opposite outcomes are also described. The effect of the methylation of this gene on different gene regions, other than the promoter, remains uncertain. We investigated the methylation profile at different genomic regions of HOXA1 in OSCC and correlated differentially methylated CpG sites with clinicopathological data.

METHODS

The HOXA1 DNA methylation status was evaluated by analyzing data from The Cancer Genome Atlas and three Gene Expression Omnibus datasets. Significant differentially methylated CpG sites were considered with a |∆β| ≥ 0.10 and a Bonferroni-corrected p-value < 0.01. Differentially methylated CpGs were validated by pyrosequencing using two independent cohorts of 15 and 47 OSCC patients, respectively.

RESULTS

Compared to normal tissues, we found significantly higher DNA methylation levels in the 3'UTR region of HOXA1 in OSCC. Higher methylation levels in tumor samples were positively correlated with smoking habits and patients' overall survival.

CONCLUSIONS

Our findings suggest that HOXA1 gene body methylation is a promising prognostic biomarker for OSCC with potential clinical applications in patient monitoring.

Epigenetics in the diagnosis and prognosis of head and neck cancer: A systematic review

BACKGROUND

Aberrant epigenetic modifications significantly develop and progress human malignancies including head and neck squamous cell carcinoma (HNSCC). Taking into account issues of late diagnosis and poor prognosis associated with HNSCC, this systematic review is designed to provide an up-to-date insight of epigenetic changes in the management of HNSCC.

METHODS

All studies that assessed the diagnostic and prognostic utilities of epigenetic changes (DNA methylation and histone modifications) among patients diagnosed with HNSCC or oral potentially malignant disorders (OPMDs) were considered for inclusion till June 2023. Pre-defined Medical Subject Headings terms were used to search Web of Science, Pubmed, Scopus and Embase Ovid databases.

RESULTS

Twenty-five studies were deemed eligible for inclusion with a total number of 3790 samples (2123 HNSCCs, 334 OPMDs and 1333 as controls). DNA methylation was investigated in 18 studies while the role of histone modifications was assessed in seven studies. The most investigated biomarkers among the studies were H3, DAPK and TIMP3. The diagnostic accuracy of the epigenetic biomarkers in detecting HNSCC was assessed in eight studies where the following biomarkers showed the highest area under the curve values: TIPM3, DCC, DAPK, SEPT9, SHOX9, HOXA9 and TRH. None of the studies assessed the predictability of the epigenetic biomarkers in HNSCC and OPMDs.

CONCLUSION

Although initial promising results were seen using the epigenetic biomarkers in the early detection of HNSCC, the limited number of patients and the absence of well-designed longitudinal studies limit the clinical applicability of the outcomes.

Methylation of the tumor associated genes in head and neck squamous cell carcinoma

Introduction. Head and neck cancer is a heterogenous group of malignant tumors of different etiologies, molecular mechanisms of which are still insufficiently studied.

Aim. Investigation of DNA methylation status of some tumor associated genes (RASSF1A, RASSF2, RASSF5, CDO1, MEST and WIF1) in patients with head and neck squamous cell carcinoma.

Materials and methods. The DNA methylation level of normal and tumor tissues was analyzed using bisulfite conversion and methylation-sensitive high-resolution melting in 25 patients (21 men and 4 women) diagnosed with neck squamous cell carcinoma.

Results. There were significant differences in levels of DNA methylation between tumor and normal tissues in the CDO1 and WIF1 genes in all groups and subgroups of patients (larynx and other cancers, squamous cell carcinoma keratinizing and non-keratinizing, primary and recurrent tumor, smokers and non-smokers). The methylation level in the CDO1 gene in tumor tissue was significantly increased in the T4 and T3 stage subgroups compared to T2.

Conclusion. The increased level of methylation of the CDO1 and WIF1 genes, as well as changes in their expression are among the molecular mechanisms involved in the neck squamous cell carcinoma development. They can be considered as prognostic and diagnostic markers for this pathology.

"Losing the Brakes"-Suppressed Inhibitors Triggering Uncontrolled Wnt/ß-Catenin Signaling May Provide a Potential Therapeutic Target in Elderly Acute Myeloid Leukemia

Dysregulated Wnt/β-catenin signal transduction is implicated in initiation, propagation, and poor prognosis in AML. Epigenetic inactivation is central to Wnt/β-catenin hyperactivity, and Wnt/β-catenin inhibitors are being investigated as targeted therapy. Dysregulated Wnt/β-catenin signaling has also been linked to accelerated aging. Since AML is a disease of old age (>60 yrs), we hypothesized age-related differential activity of Wnt/β-catenin signaling in AML patients. We probed Wnt/β-catenin expression in a series of AML in the elderly (>60 yrs) and compared it to a cohort of pediatric AML (<18 yrs). RNA from diagnostic bone marrow biopsies (n = 101) were evaluated for key Wnt/β-catenin molecule expression utilizing the NanoString platform. Differential expression of significance was defined as >2.5-fold difference (p < 0.01). A total of 36 pediatric AML (<18 yrs) and 36 elderly AML (>60 yrs) were identified in this cohort. Normal bone marrows (n = 10) were employed as controls. Wnt/β-catenin target genes (MYC, MYB, and RUNX1) showed upregulation, while Wnt/β-catenin inhibitors (CXXR, DKK1-4, SFRP1-4, SOST, and WIFI) were suppressed in elderly AML compared to pediatric AML and controls. Our data denote that suppressed inhibitor expression (through mutation or hypermethylation) is an additional contributing factor in Wnt/β-catenin hyperactivity in elderly AML, thus supporting Wnt/β-catenin inhibitors as potential targeted therapy.

Novel multiplex stool-based assay for the detection of early-stage colon cancer in a Chinese population

BACKGROUND

Stool DNA (sDNA) methylation analysis is a promising, noninvasive approach for colorectal cancer screening; however, reliable biomarkers for detecting early-stage colon cancer (ECC) are lacking, particularly in the Chinese population.

AIM

To identify a novel stool-based assay that can improve the effectiveness of ECC screening.

METHODS

A blinded case-control study was performed using archived stool samples from 125 ECC patients, and 125 control subjects with normal colonoscopy. The cohort was randomly divided into training and test sets at a 1.5:1 ratio. Targeted bisulfite sequencing (TBSeq) was conducted on five pairs of preoperative and postop-erative sDNA samples from ECC patients to identify DNA methylation biomarkers, which were validated using pyrosequencing. By logistic regression analysis, a multiplex stool-based assay was developed in the training set, and the detection performance was further assessed in the test set and combined set. The χ² test was used to investigate the association of detection sensitivity with clinico-pathological features.

RESULTS

Following TBSeq, three hypermethylated cytosine-guanine sites were selected as biomarkers, including paired box 8, Ras-association domain family 1 and secreted frizzled-related protein 2, which differed between the groups and were involved in important cancer pathways. An sDNA panel containing the three biomarkers was constructed with a logistic model. Receiver operating characteristic (ROC) analysis revealed that this panel was superior to the fecal immunochemical test (FIT) or serum carcinoembryonic antigen for the detection of ECC. We further found that the combination of the sDNA panel with FIT could improve the screening effectiveness. In the combined set, the sensitivity, specificity and area under the ROC curve for this multiplex assay were 80.0%, 93.6% and 0.918, respectively, and the performance remained excellent in the subgroup analysis by tumor stage. In addition, the detection sensitivity did not differ with tumor site, tumor stage, histological differentiation, age or sex, but was significantly higher in T4 than in T1-3 stage tumors (P = 0.041).

CONCLUSION

We identified a novel multiplex stool-based assay combining sDNA methylation biomarkers and FIT, which could detect ECC with high sensitivity and specificity throughout the colon, showing a promising application perspective.

DNA Methylation Markers from Negative Surgical Margins Can Predict Recurrence of Oral Squamous Cell Carcinoma

The identification of molecular markers in negative surgical margins of oral squamous cell carcinoma (OSCC) might help in identifying residual molecular aberrations, and potentially improve the prediction of prognosis. We performed an Infinium MethylationEPIC BeadChip array on 32 negative surgical margins stratified based on the status of tumor recurrence in order to identify recurrence-specific aberrant DNA methylation (DNAme) markers. We identified 2512 recurrence-associated Differentially Methylated Positions (DMPs) and 392 Differentially Methylated Regions (DMRs) which were enriched in cell signaling and cancer-related pathways. A set of 14-CpG markers was able to discriminate recurrent and non-recurrent cases with high specificity and sensitivity rates (AUC 0.98, p = 3 × 10-6; CI: 0.95-1). A risk score based on the 14-CpG marker panel was applied, with cases classified within higher risk scores exhibiting poorer survival. The results were replicated using tumor-adjacent normal HNSCC samples from The Cancer Genome Atlas (TCGA). We identified residual DNAme aberrations in the negative surgical margins of OSCC patients, which could be informative for patient management by improving therapeutic intervention. This study proposes a novel DNAme-based 14-CpG marker panel as a promising predictor for tumor recurrence, which might contribute to improved decision-making for the personalized treatment of OSCC cases.

MicroRNA-27a targets Sfrp1 to induce renal fibrosis in diabetic nephropathy by activating Wnt/β-Catenin signalling

Diabetic nephropathy (DN) commonly causes end-stage renal disease (ESRD). Increasing evidence indicates that abnormal miRNA expression is tightly associated with chronic kidney disease (CKD). This work aimed to investigate whether miR-27a can promote the occurrence of renal fibrosis in DN by suppressing the expression of secreted frizzled-related protein 1 (Sfrp1) to activate Wnt/β-catenin signalling. Therefore, we assessed the expression levels of miR-27a, Sfrp1, Wnt signalling components, and extracellular matrix (ECM)-related molecules in vitro and in vivo. Sfrp1 was significantly down-regulated in a high-glucose environment, while miR-27a levels were markedly increased. A luciferase reporter assay confirmed that miR-27a down-regulated Sfrp1 by binding to the 3′ untranslated region directly. Further, NRK-52E cells under high-glucose conditions underwent transfection with miR-27a mimic or the corresponding negative control, miR-27a inhibitor or the corresponding negative control, si-Sfrp1, or combined miR-27a inhibitor and si-Sfrp1. Immunoblotting and immunofluorescence were performed to assess the relative expression levels of Wnt/β-catenin signalling and ECM components. The mRNA levels of Sfrp1, miR-27a, and ECM-related molecules were also detected by quantitative real-time PCR (qPCR). We found that miR-27a inhibitor inactivated Wnt/β-catenin signalling and reduced ECM deposition. Conversely, Wnt/β-catenin signalling was activated, while ECM deposition was increased after transfection with si-Sfrp1. Interestingly, miR-27a inhibitor attenuated the effects of si-Sfrp1. We concluded that miR-27a down-regulated Sfrp1 and activated Wnt/β-catenin signalling to promote renal fibrosis.

Comprehending the crosstalk between Notch, Wnt and Hedgehog signaling pathways in oral squamous cell carcinoma - clinical implications

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a malignant oral cavity neoplasm that affects many people, especially in developing countries. Despite several advances that have been made in diagnosis and treatment, the morbidity and mortality rates due to OSCC remain high. Accumulating evidence indicates that aberrant activation of cellular signaling pathways, such as the Notch, Wnt and Hedgehog pathways, occurs during the development and metastasis of OSCC. In this review, we have articulated the roles of the Notch, Wnt and Hedgehog signaling pathways in OSCC and their crosstalk during tumor development and progression. We have also examined possible interactions and associations between these pathways and treatment regimens that could be employed to effectively tackle OSCC and/or prevent its recurrence.

CONCLUSIONS

Activation of the Notch signaling pathway upregulates the expression of several genes, including c-Myc, β-catenin, NF-κB and Shh. Associations between the Notch signaling pathway and other pathways have been shown to enhance OSCC tumor aggressiveness. Crosstalk between these pathways supports the maintenance of cancer stem cells (CSCs) and regulates OSCC cell motility. Thus, application of compounds that block these pathways may be a valid strategy to treat OSCC. Such compounds have already been employed in other types of cancer and could be repurposed for OSCC.

Hypermethylated PAX1 and ZNF582 genes in the tissue sample are associated with aggressive progression of oral squamous cell carcinoma

BACKGROUND

DNA methylation of paired box gene 1 (PAX1) and zinc finger 582 (ZNF582) is promising cancer biomarkers for oral squamous cell carcinoma detection. This study aims to investigate the correlation between PAX1 or ZNF582 methylation and the progression of oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

A total of 135 OSCC cases from Peking University School and Hospital of Stomatology were enrolled in this study. Tissue specimens were collected from the lesion site and corresponding adjacent normal site. The methylation level of these two genes was evaluated in primary and recurrent OSCC group.

RESULTS

Hypermethylation of PAX1 or ZNF582 was observed in lesion sites among primary and recurrent OSCC cases. In the lesion site of primary cases, promoter methylation was observed in T3/T4 (PAX1: P = .02; ZNF582: P = .01), stage III/IV (PAX1: P = .03; ZNF582: P = .01), and bone invasion cases (PAX1: P = .02; ZNF582: P = .047). In the subgroup analysis, the correlation between hypermethylation and OSCC severity remains significant with exposure to smoking/alcohol consumption.

CONCLUSIONS

Hypermethylated PAX1 and ZNF582 can sufficiently act as biomarkers to reflect the severity or progression of OSCC.

Epigenetic Modifications in Head and Neck Cancer

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common human malignancy in the world, with high mortality and poor prognosis for patients. Among the risk factors are tobacco and alcohol intake, human papilloma virus, and also genetic and epigenetic modifications. Many studies show that epigenetic events play an important role in HNSCC development and progression, including DNA methylation, chromatin remodeling, histone posttranslational covalent modifications, and effects of non-coding RNA. Epigenetic modifications may influence silencing of tumor suppressor genes by promoter hypermethylation, regulate transcription by microRNAs and changes in chromatin structure, or induce genome instability through hypomethylation. Moreover, getting to better understand aberrant patterns of methylation may provide biomarkers for early detection and diagnosis, while knowledge about target genes of microRNAs may improve the therapy of HNSCC and extend overall survival. The aim of this review is to present recent studies which demonstrate the role of epigenetic regulation in the development of HNSCC.