Serum miR-483-5p: a novel diagnostic and prognostic biomarker for patients with oral squamous cell carcinoma

miR-483-5p orchestrates the initiation of protein synthesis by facilitating the decrease in phosphorylated Ser209eIF4E and 4E-BP1 levels

Eukaryotic initiation factor 4E (eIF4E) is a pivotal protein involved in the regulatory mechanism for global protein synthesis in both physiological and pathological conditions. MicroRNAs (miRNAs) play a significant role in regulating gene expression by targeting mRNA. However, the ability of miRNAs to regulate eIF4E and its phosphorylation remains relatively unknown. In this study, we predicted and experimentally verified targets for miR-483-5p, including eukaryotic translation initiation factor eIF4E and its binding proteins, 4E-BPs, that regulate protein synthesis. Using the Web of Science database, we identified 28 experimentally verified miR-483-5p targets, and by the TargetScan database, we found 1818 predicted mRNA targets, including EIF4E, EIF4EBP1, and EIF4EBP2. We verified that miR-483-5p significantly reduced ERK1 and MKNK1 mRNA levels in HEK293 cells. Furthermore, we discovered that miR-483-5p suppressed EIF4EBP1 and EIF4EBP2, but not EIF4E. Finally, we found that miR-483-5p reduced the level of phosphorylated eIF4E (pSer209eIF4E) but not total eIF4E. In conclusion, our study suggests that miR-483-5p's multi-targeting effect on the ERK1/ MKNK1 axis modulates the phosphorylation state of eIF4E. Unlike siRNA, miRNA can have multiple targets in the pathway, and thereby exploring the role of miR-483-5p in various cancer models may uncover therapeutic options.

Unraveling the role of miRNAs in the diagnosis, progression, and drug resistance of oral cancer

Oral cancer (OC) is a widely observed neoplasm on a global scale. Over time, there has been an increase in both its fatality and incidence rates. Oral cancer metastasis is a complex process that involves a number of cellular mechanisms, including invasion, migration, proliferation, and escaping from malignant tissue through either lymphatic or vascular channels. MicroRNAs (miRNAs) are a crucial class of short non-coding RNAs recognized as significant modulators of diverse cellular processes and exert a pivotal influence on the carcinogenesis pathway, functioning either as tumor suppressors or as oncogenes. It has been shown that microRNAs (miRNAs) have a role in metastasis at several stages, including epithelial-mesenchymal transition, migration, invasion, and colonization. This regulation is achieved by targeting key genes involved in these pathways by miRNAs. This paper aims to give a contemporary analysis of OC, focusing on its molecular genetics. The current literature and emerging advancements in miRNA dysregulation in OC are thoroughly examined. This project would advance OC diagnosis, prognosis, therapy, and therapeutic implications.

Unveiling the Potential of Serum MiR-483-5p: A Promising Diagnostic and Prognostic Biomarker in OLP and OSCC Patients by In silico Analysis of Differential Gene Expression

BACKGROUND

Oral squamous cell carcinoma (OSCC) and oral lichen planus (OLP) are two separate conditions affecting the mouth and result in varying clinical outcomes and levels of malignancy. Achieving early diagnosis and effective therapy planning requires the identification of reliable diagnostic biomarkers for these disorders. MicroRNAs (miRNAs) have recently received attention as powerful biomarkers for various illnesses, including cancer. In particular, miR-483-5p is a promising diagnostic and prognostic biomarker in various cancers. Therefore, this study aimed to investigate the role of serum miR-483-5p in the diagnosis and prognosis of OLP and OSCC patients by in silico analysis of differential gene expression.

METHODS

GSE23558 and GSE52130 data sets were selected, and differential gene expression analysis was performed using microarray data from GSE52130 and GSE23558. The analysis focused on comparing OLP and OSCC samples with normal samples. The genes intersected through the differential gene expression analysis were then extracted to determine the overlapping genes among the upregulated or downregulated DEGs. The downregulated genes among the DEGs were subsequently imported into the miRWalk database to search for potential target genes of miRNA 483-5p that lacked validation. To gain insight into the biological pathways associated with the DEGs, we conducted pathway analysis utilizing tools, such as Enrichr. Additionally, the cellular components associated with these DEGs were investigated by analyzing the String database. On the other hand, blood serum samples were collected from 35 OSCC patients, 34 OLP patients, and 34 healthy volunteers. The expression level of miR-483-5p was determined using quantitative reverse transcription polymerase chain reaction (RT-qPCR). The Kruskal-Wallis test was utilized to investigate the considerable correlation. Moreover, this study explored the prognostic value of miR-483-5p through its association with clinicopathological parameters in OSCC patients.

RESULTS

The results showed that serum expression of miR-483-5p was considerably higher in OSCC patients compared to OLP patients and healthy controls (p 0.0001) and that this difference was statistically significant. Furthermore, elevated miR-483-5p expression was associated with tumor size, lymph node metastasis, and stage of tumor nodal metastasis in OSCC patients (p 0.001, p 0.038, and p 0.0001, respectively). In silico analysis found 71 upregulated genes at the intersection of upregulated DEGs and 44 downregulated genes at the intersection of downregulated DEGs, offering insight into the potential underlying mechanisms of miR-483-5p's engagement in OSCC and OLP. The majority of these DEGs were found to be involved in autophagy pathways, but DEGs involved in the histidine metabolism pathway showed significant results. Most of these DEGs were located in the extracellular region. After screening for downregulated genes that were invalidated, miRNA 483-5p had 7 target genes.

CONCLUSION

This study demonstrates the potential of serum miR-483-5p as a promising diagnostic and prognostic biomarker in OSCC and OLP patients. Its upregulation in OSCC patients and its association with advanced tumor stage and potential metastasis suggest the involvement of miR-483-5p in critical signaling pathways involved in cell proliferation, apoptosis, and cell cycle regulation, making it a reliable indicator of disease progression. Nevertheless, additional experimental studies are essential to validate these findings and establish a foundation for the advancement of targeted therapies and personalized treatment approaches.

Identification of a serum-based microRNA signature that detects recurrent oral squamous cell carcinoma before it is clinically evident

BACKGROUND

Survival rates for oral squamous cell carcinoma (OSCC) have remained poor for decades, a fact largely attributable to late-stage diagnoses and high recurrence rates. We report analysis of serum miRNA expression in samples from patients with high-risk oral lesions (HRL, including OSCC/carcinoma in situ lesions) and healthy non-cancer controls, with the aim of non-invasively detecting primary or recurrent disease before it is clinically evident.

METHODS

Discovery, test, and validation sets were defined from a total of 468 serum samples (305 HRL and 163 control samples). Samples were analysed using multiple qRT-PCR platforms.

RESULTS

A two-miRNA classifier comprised of miR-125b-5p and miR-342-3p was defined following discovery and test analyses. Analysis in an independent validation cohort reported sensitivity and specificity of ~74% for this classifier. Significantly, when this classifier was applied to serial serum samples taken from patients both before treatment and during post-treatment surveillance, it identified recurrence an average of 15 months prior to clinical presentation.

CONCLUSIONS

These results indicate this serum miRNA classifier is effective as a simple, non-invasive monitoring tool for earlier detection of recurrent disease when lesions are typically smaller and amenable to a wider array of treatment options to improve survival.

Emerging cell cycle related non-coding RNA biomarkers from saliva and blood for oral squamous cell carcinoma

The unnotified or undifferentiable early stages of oral squamous cell carcinoma (OSCC) progression are the prime reasons for late-stage detection and poor survival outcomes of oral cancer. This review summarizes the prior research and recent advancements on the influence of dysregulated non-coding RNA (ncRNA) on cell cycle and their employability as diagnostic and prognostic biomarkers of oral cancer. The literature search was performed using the following keywords: 'serum/saliva non-coding RNAs' and 'serum/saliva non-coding RNAs and cell cycle', 'serum/saliva dysregulated ncRNAs and cell cycle', 'Cdk/CKI and ncRNAs', 'tissue ncRNAs' concerning 'oral cancer''. The compiled data focuses mainly on the diagnostic and prognostic significance of MicroRNAs (miRNAs), Circular RNAs (circRNAs), and Long noncoding RNAs (lncRNAs) on oral cancer and all other cancers as well as subject-relevant articles published in languages other than English are beyond the scope of this review and excluded from the study. Moreover, articles focusing on DNA, protein, and metabolite markers are eliminated from the study. While there exist various potential biomolecules such as DNA, RNA, proteins, metabolites, and specific antigens representing predictive biomarkers in body fluids for oral cancer, this review completely focuses on non-coding RNAs restricted to saliva and blood, picking out a few of the reliable ones amongst the recent investigations based on the sophisticated techniques, cohort, and sensitivity as well as specificity, i.e., salivary miR-1307-5p, miR-3928, hsa_circ_0001874 and ENST00000412740, NR_131012, ENST00000588803, NR_038323, miR-21 in circulation. Thus, further studies are required to clinically confirm the usage of these non-invasive biomarkers in oral cancer.

miR-99a-5p as a biomarker for lymph node metastasis prediction in oral squamous cell carcinoma patients

BACKGROUND

Metastatic lymph node involvement influences therapy decisions and serves as a prognostic indicator in oral squamous cell carcinoma (OSCC). However, many early-stage patients with clinically negative lymph nodes exhibit no metastasis upon surgical staging. This study aimed to identify differentially expressed miRNAs capable of distinguishing pathologically positive (pN+) from negative (pN0) nodes in OSCC patients without clinical evidence of lymph node metastases (cN0).

METHODS

Expression levels of 798 miRNAs were assessed in tumor samples from 10 pN+ and 10 pN0 patients using the Nanostring nCounter platform. Validation was performed in an independent cohort of 15 pN+ and 24 pN0 patients through RT-qPCR.

RESULTS

Eight miRNAs exhibited differential expression between pN0 and pN+ patients. Notably, hsa-miR-99a-5p demonstrated high sensitivity and specificity in predicting patients at higher risk of positive lymph nodes.

CONCLUSIONS

These findings highlight hsa-miR-99a-5p as a potential biomarker for detecting lymph node metastasis in primary OSCC tumors.

Identification of Neck Lymph Node Metastasis-Specific microRNA-Implication for Use in Monitoring or Prediction of Neck Lymph Node Metastasis

MicroRNAs (miRNAs) have attracted attention as non-invasive cancer biomarkers in various cancers; however, they have not been adequately investigated in oral squamous cell carcinoma (OSCC). This study investigated the diagnostic performance of serum-derived miRNAs at initial diagnosis for primary neck lymph node metastasis and the predictive performance for late neck lymph node metastasis based on long-term (up to approximately 8 years) follow-up of patients with OSCC. The expression of miRNAs in 40 patients with OSCC was quantified using real-time PCR (qPCR), and a comprehensive statistical analysis of the correlation of miRNA expression for primary and late neck lymph node metastases was performed. For the diagnosis of primary neck lymph node metastases, miR-423 and miR-125 were accurate. The miRNA index for primary metastasis diagnosis (miR-PM) calculated by regression analysis showed high diagnostic accuracy. The miR-5100 was useful for predicting late neck lymph node metastases. The miRNA index for late metastasis prediction (miR-LM) calculated using regression analysis showed high prediction accuracy. MiRNAs were useful for diagnosing primary neck lymph node metastases in OSCC and predicting late neck lymph node metastases. It may help to consider individualized treatment, including follow-up, surgical methods, and postoperative management.

miRNAs as potential game-changers in head and neck cancer: Future clinical and medicinal uses

Head and neck cancers (HNCs) are a group of heterogeneous tumors formed most frequently from epithelial cells of the larynx, lips, oropharynx, nasopharynx, and mouth. Numerous epigenetic components, including miRNAs, have been demonstrated to have an impact on HNCs characteristics like progression, angiogenesis, initiation, and resistance to therapeutic interventions. The miRNAs may control the production of numerous genes linked to HNCs pathogenesis. The roles that miRNAs play in angiogenesis, invasion, metastasis, cell cycle, proliferation, and apoptosis are responsible for this impact. The miRNAs also have an impact on crucial HNCs-related mechanistic networks like the WNT/β-catenin signaling, PTEN/Akt/mTOR pathway, TGFβ, and KRAS mutations. miRNAs may affect how the HNCs respond to treatments like radiation and chemotherapy in addition to pathophysiology. This review aims to demonstrate the relationship between miRNAs and HNCs with a particular emphasis on how miRNAs impact HNCs signaling networks.

Circulating miRNA as a Biomarker in Oral Cancer Liquid Biopsy

Oral cancer is currently challenging the healthcare system, with a high incidence among the population and a poor survival rate. One of the main focuses related to this malignancy is the urge to implement a viable approach for improving its early diagnosis. By introducing the use of liquid biopsy and the identification of potential biomarkers, aiming for a noninvasive approach, new advancements offer promising perspectives in the diagnosis of oral cancer. The present review discusses the potential of circulating miRNAs as oral cancer biomarkers identified in body fluids such as serum, plasma, and saliva samples of oral cancer patients. Existing results reveal an important implication of different miRNA expressions involved in the initiation, development, progression, and metastasis rate of oral malignancy. Liquid biomarkers can play a crucial role in the development of the concept of personalized medicine, providing a wide range of clinical applications and future targeted therapies.

MiRNAs as non-invasive biomarkers in the serum of Oral Squamous Cell Carcinoma (OSCC) and Oral Potentially Malignant Disorder (OPMD) patients

OBJECTIVE

Cell-free microRNAs have shown differential levels in the serum of individuals under disease conditions suggesting its potential to act as biomarkers. A population specific miRNA signature in oral cancer is reported in different studies. We aim to identify a set of serum specific miRNAs that may differentiate oral cancer, oral pre-malignant conditions from the healthy individuals.

DESIGN

We investigated the levels of 24 miRNAs in the serum of 47 Oral squamous cell carcinoma (OSCC) patients, 20 patients with Oral potentially malignant disorders (OPMD) and 42 healthy controls from Eastern India. Small RNAs were isolated from serum samples followed by cDNA synthesis. Levels of miRNAs were determined using qRT-PCR. The sources of serum specific miRNAs were evaluated using GTEx-RNAseq and TCGA-HNSCC database.

RESULTS

Five miRNAs, miR-483-5p, miR-31-5p, Let-7b-5p, miR-486-5p and miR-30e-5p showed significant elevation in OSCC patients. An Elastic-Net model with 4 miRNAs classified OSCC from healthy controls with 80 % sensitivity, 64.3 % specificity, and 72.4 % accuracy. Mir-483-5p and miR-31-5p was significantly overexpressed in OSCC tissues as well as significantly higher in the serum of Leukoplakia and Verrucous carcinoma patients suggesting their potential as early disease markers. MiR-483-5p showed a consistent elevated level in the serum/plasma of oral cancer patients across different population and was found to be tumour specific while, the rest of the miRNAs showed variable results across different studies.

CONCLUSIONS

Our study suggested that the serum miRNAs in oral cancer and pre-malignant disorder conditions can be used as a non-invasive marker for screening of these oral conditions.

The paradigm of miRNA and siRNA influence in Oral-biome

Short nucleotide sequences like miRNA and siRNA have attracted a lot of interest in Oral-biome investigations. miRNA is a small class of non-coding RNA that regulates gene expression to provide effective regulation of post-transcription. On contrary, siRNA is 21-25 nucleotide dsRNA impairing gene function post-transcriptionally through inhibition of mRNA for homologous dependent gene silencing. This review highlights the application of miRNA in oral biome including oral cancer, dental implants, periodontal diseases, gingival fibroblasts, oral submucous fibrosis, radiation-induced oral mucositis, dental Pulp, and oral lichenoid disease. Moreover, we have also discussed the application of siRNA against the aforementioned disease along with the impact of miRNA and siRNA to the various pathways and molecular effectors pertaining to the dental diseases. The influence of upregulation and downregulation of molecular effector post-treatment with miRNA and siRNA and their impact on the clinical setting has been elucidated. Thus, the mentioned details on application of miRNA and siRNA will provide a novel gateway to the scholars to not only mitigate the long-lasting issue in dentistry but also develop new theragnostic approaches.

Integrating Cutting-Edge Methods to Oral Cancer Screening, Analysis, and Prognosis

Oral cancer (OC) has become a significant barrier to health worldwide due to its high morbidity and mortality rates. OC is among the most prevalent types of cancer that affect the head and neck region, and the overall survival rate at 5 years is still around 50%. Moreover, it is a multifactorial malignancy instigated by genetic and epigenetic variabilities, and molecular heterogeneity makes it a complex malignancy. Oral potentially malignant disorders (OPMDs) are often the first warning signs of OC, although it is challenging to predict which cases will develop into malignancies. Visual oral examination and histological examination are still the standard initial steps in diagnosing oral lesions; however, these approaches have limitations that might lead to late diagnosis of OC or missed diagnosis of OPMDs in high-risk individuals. The objective of this review is to present a comprehensive overview of the currently used novel techniques viz., liquid biopsy, next-generation sequencing (NGS), microarray, nanotechnology, lab-on-a-chip (LOC) or microfluidics, and artificial intelligence (AI) for the clinical diagnostics and management of this malignancy. The potential of these novel techniques in expanding OC diagnostics and clinical management is also reviewed.

The clinical implications of circulating microRNAs as potential biomarkers in screening oral squamous cell carcinoma

Background

Recent studies have highlighted the biomarker role of circulating miRNAs in oral squamous cell carcinoma (OSCC), indicating their potential application as early diagnostic markers for OSCC. However, the diagnostic results have proven inconclusive. This study was conducted to evaluate the diagnostic value of circulating miRNAs for OSCC diagnosis.

Methods

Eligible published studies were identified by a literature search carried out in several databases by using combinations of keywords associated with OSCC, circulating miRNAs, and diagnosis. The bivariate meta-analysis model was adopted to summarize the pooled parameters. Afterwards, we thoroughly explored the sources of heterogeneity after evaluating the risk of bias.

Results

A total of 60 studies focusing on 41 circulating miRNAs were included. The pooled sensitivity, specificity, and AUC were 0.75 (95%CI: 0.69-0.80), 0.76 (0.70-0.81), 0.82 (0.79-0.85), respectively. Subgroup analyses showed that miRNA combinations were more accurate than single miRNAs. Additionally, plasma may be a better matrix for miRNAs assays in OSCC diagnosis as the plasma-based miRNA assay had a higher level of diagnostic accuracy than serum-based miRNA assay. Subgroup analyses also suggested that using circulating miRNAs for OSCC diagnosis is more effective in Caucasians than in Asian ethnic groups. Finally, circulating miRNA assays based on large sample sizes have superior diagnostic accuracy than small sample sizes.

Conclusion

Circulating miRNAs might be applied as effective surrogate biomarkers for early diagnosis of OSCC. Nevertheless, future larger-scale prospective studies should be performed to enhance the diagnostic efficiency and investigate the miRNA combinations with more pronounced accuracy.

Promising Biomarkers in Head and Neck Cancer: The Most Clinically Important miRNAs

Head and neck cancers (HNCs) comprise a heterogeneous group of tumors that extend from the oral cavity to the upper gastrointestinal tract. The principal etiologic factors for oral tumors include tobacco smoking and alcohol consumption, while human papillomavirus (HPV) infections have been accused of a high incidence of pharyngeal tumors. Accordingly, HPV detection has been extensively used to categorize carcinomas of the head and neck. The diverse nature of HNC highlights the necessity for novel, sensitive, and precise biomarkers for the prompt diagnosis of the disease, its successful monitoring, and the timely prognosis of patient clinical outcomes. In this context, the identification of certain microRNAs (miRNAs) and/or the detection of alterations in their expression patterns, in a variety of somatic fluids and tissues, could serve as valuable biomarkers for precision oncology. In the present review, we summarize some of the most frequently studied miRNAs (including miR-21, -375, -99, -34a, -200, -31, -125a/b, -196a/b, -9, -181a, -155, -146a, -23a, -16, -29, and let-7), their role as biomarkers, and their implication in HNC pathogenesis. Moreover, we designate the potential of given miRNAs and miRNA signatures as novel diagnostic and prognostic tools for successful patient stratification. Finally, we discuss the currently ongoing clinical trials that aim to identify the diagnostic, prognostic, or therapeutic utility of miRNAs in HNC.

The Connection between MicroRNAs and Oral Cancer Pathogenesis: Emerging Biomarkers in Oral Cancer Management

Oral cancer is a common human malignancy that still maintains an elevated mortality rate despite scientific progress. Tumorigenesis is driven by altered gene expression patterns of proto-oncogenes and tumor-suppressor genes. MicroRNAs, a class of short non-coding RNAs involved in gene regulation, seem to play important roles in oral cancer development, progression, and tumor microenvironment modulation. As properties of microRNAs render them stable in diverse liquid biopsies, together with their differential expression signature in cancer cells, these features place microRNAs at the top of promising biomarkers for diagnostic and prognostic values. In this review, we highlight eight expression levels and functions of the most relevant microRNAs involved in oral cancer development, progression, and microenvironment sustainability. Furthermore, we emphasize the potential of using these small RNA species as non-invasive biomarkers for the early detection of oral cancerous lesions. Conclusively, we highlight the perspectives and limitations of microRNAs as novel diagnostic tools, as well as therapeutic models.

Liquid Biopsy as a Tool for the Characterisation and Early Detection of the Field Cancerization Effect in Patients with Oral Cavity Carcinoma

Oral squamous cell carcinoma (OSCC) constitutes approximately 25% of all head and neck cancer, for which the consumption of tobacco and alcohol are the main associated risk factors. The field cancerization effect of OSCC is one of the main reasons for the poor survival rates associated with this disease. Despite some advances, its ccharacterization and early diagnosis continue to challenge modern oncology, and the goal of improving the prognosis remains to be achieved. Among new early diagnostic tools for OSCC that have been proposed, liquid biopsy appears to be an ideal candidate, as studies have shown that the analysis of blood and saliva provides promising data for the early detection of relapses or second tumours.

Aberrant expression of miR-483-5p in patients with asymptomatic carotid artery stenosis and its predictive value for cerebrovascular event occurrence

MicroRNAs (miRNAs/miRs) may be used as novel promising diagnostic and prognostic biomarkers for various diseases, including asymptomatic carotid artery stenosis (ACAS). The present study aimed to investigate the abnormal expression of microRNA-483-5p (miR-483-5p) in patients with ACAS and to evaluate its diagnostic value for ACAS screening and its predictive value for cerebrovascular events. A total of 128 patients with ACAS and 76 healthy controls were included in the present study. The expression of miR-483-5p in serum was measured by reverse transcription-quantitative PCR. Receiver operating characteristic (ROC) curve analysis was used to evaluate the diagnostic value of miR-483-5p in patients with ACAS. Kaplan-Meier curves were drawn and Cox regression analysis was used to determine the predictive value of miR-483-5p for cerebrovascular events in patients with ACAS. Serum miR-483-5p levels were significantly increased in patients with ACAS as compared with those in healthy controls. The expression of miR-483-5p was significantly associated with diabetes (P=0.011), dyslipidemia (P=0.047) and the degree of carotid stenosis (P=0.006) in patients with ACAS. In addition, the area under the ROC curve was 0.910, with a sensitivity of 80.5% and a specificity of 89.5% at the cutoff value of 0.705, indicating that serum miR-483-5p expression has a certain diagnostic value in patients with ACAS. Furthermore, the patients with high miR-483-5p expression had a higher proportion of cerebrovascular events than patients with low miR-483-5p levels (log-rank P=0.011) and miR-483-5p was an independent prognostic marker for predicting the occurrence of cerebrovascular events in patients with ACAS. The results indicated that miR-483-5p expression is significantly increased in patients with ACAS and that abnormal miR-483-5p expression may be a candidate biomarker for ACAS diagnosis and the prediction of cerebrovascular event occurrence.

The scope of liquid biopsy in the clinical management of oral cancer

Oral squamous cell carcinoma (OSCC) is one of the most prevalent forms of head and neck cancer, and it remains a leading cause of death in developing countries. Failure to detect the disease at an early stage is the main reason for the lack of improvement in the overall survival rate over the decades. Even though tissue biopsy is considered as the gold standard for diagnosis and molecular workup, it is an invasive, expensive and time-consuming procedure. Besides, it may not indicate the genetic status of the entire tumour owing to the heterogeneity of the cancer. In this context, liquid biopsy could be quite useful as it provides a more representative picture of the circulating tumour cells, circulating tumour DNA, circulating RNA, and tumour-derived exosomes obtained from all types of body fluids. This technique provides real-time assessment of variations in the molecular profile of the whole tumour and enables the serial monitoring of the disease status. The method has many advantages, such as easy accessibility, reliability, reproducibility and the possibility for early detection of the disease. However, the concept is still in its infancy, and the research on its application in various tumours including OSCC is rapidly progressing.

Detection of CAF-1/p60 in peripheral blood as a potential biomarker of HNSCC tumors

To date, a very small number of serum biomarkers have been identified for clinical use in squamous carcinomas of the head and neck region. Chromatin Assembly Factor-1 (CAF-1) heterotrimeric complex subunit CAF1/p60 expression levels have been reported to be of prognostic value in Oral Squamous Cell Carcinoma (OSCC), as well as in other human solid tumors. Here our aim was to detect and quantify CAF1/p60 in the peripheral blood of Head and Neck Squamous Cell Carcinoma (HNSCC) patients, and to investigate the possible associations between serum concentration of CAF-1/p60 and HNSCC tumors. A total of 63 HNSCC patients (51 OSCC, 8 OPSCC, 3 laryngeal SCC, and 1 rhinopharynx SCC) and 30 healthy controls were enrolled. The serum levels of CAF-1/p60 were measured by ELISA assay before and after surgery. Serum CAF-1/p60 concentration resulted significantly higher in cancer patients, compared with healthy controls, in pre-surgery samples (P < 0.05). Serum levels of CAF-1/p60 significantly decreased in serum samples taken after surgery (P < 0.05). Our results demonstrated that CAF-1/p60 may be detected in serum, suggesting a role for CAF-1/p60 as potential soluble biomarkers in HNSCC tumors.

Exosome-derived microRNAs in oral squamous cell carcinomas impact disease prognosis

OBJECTIVES

microRNA (miRNA) expression patterns have provided new insight as biomarkers of prognosis as well as novel therapeutic targets for several neoplasms. However, the role of exosomal miRNA in the prognosis of oral squamous cell carcinoma (OSCC) has not yet been completely clarified. Paired primary tumor and normal oral epithelial cells from OSCC patients were obtained, and the exosomal miRNA profiles between them were compared by miRNA microarray analysis. The miRNA levels in the serum exosomes of OSCC patients were verified by real-time quantitative reverse transcription PCR (qRT-PCR) analysis. Finally, the biological functions and the potential as a prognostic marker of the selected miRNA candidates were analyzed in the OSCC cells and patients, respectively.

RESULTS

Exosomal miR-155 and miR-21 were significantly upregulated, and exosomal miR-126 was dramatically downregulated in the primary OSCC cells and the serum of OSCC patients. In the analysis of oncogenic behaviors, coculture with either miR-155-rich or miR-21-rich exosomes could promote cell proliferation and invasion accompanied with downregulation of PTEN and Bcl-6 tumor suppressors. Moreover, treatment with miR-126-rich exosomes inhibited oncogenic behaviors and oncogene EGFL7 expression in OSCC cells. Finally, exosomal miR-126 was reduced in the serum of the late-staged OSCC patients, and downregulation of blood exosomal miR-126 was associated with poor survival in OSCC patients.

CONCLUSION

Exosomal miR-155 and miR-21 are oncogenic miRNAs which suppress PTEN and Bcl-6 expression, and exosomal miR-126 acts as a tumor suppressor which downregulates EGFL7 in OSCC. Furthermore, blood exosomal miRNAs may serve as biomarkers for the diagnosis and prognosis of OSCC.

High Expression of miR-483-5p Predicts Chemotherapy Resistance in Epithelial Ovarian Cancer

BACKGROUND

Ovarian cancer is the most deadly that requires novel diagnostics and therapeutics. MicroRNAs are viewed as essential gene regulatory elements involved in different pathobiological mechanisms of many cancers, including ovarian cancer.

OBJECTIVE

This study examined the relationship between microRNA (miRNA) expression and response to platinum-based chemotherapy.

METHODS

Genome-wide miRNA expression analysis was conducted using epithelial ovarian cancer (EOC) tissues from 25 patients with 17 malignant tumors and eight benign ovarian tumors. Candidate miRNAs that respond to platinum-based chemotherapy were selected for validation by quantitative RT-PCR.

RESULTS

Among 2,578 mature human miRNAs, high expression of miR-483-5p correlated with poor responses to platinum-based chemotherapy in EOC patients. Furthermore, high levels of miR-483-5p in the resistant group suppressed expression of the apoptotic regulator TAOK-1.

CONCLUSION

A possible marker for the prediction of chemotherapy response and resistance in patients may be miR-483-5p. Choosing the right treatment for each patient with EOC can avoid the risk of developing chemotherapy resistance.

MicroRNAs as Modulators of Oral Tumorigenesis-A Focused Review

Oral cancers constitute the majority of head and neck tumors, with a relatively high incidence and poor survival rate in developing countries. While the five-year survival rates of the oral cancer patients have increased to 65%, the overall survival for advanced stages has been at 27% for the past ten years, emphasizing the necessity for further understanding the etiology of the disease, diagnosis, and formulating possible novel treatment regimens. MicroRNAs (miRNAs), a family of small non-coding RNA, have emerged as master modulators of gene expression in various cellular and biological process. Aberrant expression of these dynamic molecules has been associated with many human diseases, including oral cancers. The deregulated miRNAs have been shown to control various oncogenic processes, including sustaining proliferative signaling, evading growth suppressors, resisting cell death activating invasion and metastasis, and inducing angiogenesis. Hence, the aberrant expression of miRNAs associated with oral cancers, makes them potential candidates for the investigation of functional markers, which will aid in the differential diagnosis, prognosis, and development of novel therapeutic regimens. This review presents a holistic insight into our understanding of the role of miRNAs in regulating various hallmarks of oral tumorigenesis.

The Emerging Role of Exosomes in Oral Squamous Cell Carcinoma

Oral cancer constitutes approximately 2% of all cancers, while the most common type, oral squamous cell carcinoma (OSCC) represents 90% of oral cancers. Although the treatment of OSCC has improved recently, it still has a high rate of local recurrence and poor prognosis, with a 5-year survival rate of only 50%. Advanced stage OSCC tends to metastasize to lymph nodes. Thus, exploring new therapeutic strategies for OSCC is therefore an urgent priority. Exosomes, the small membrane vesicles derived from endosomes, have been detected in a wide array of bodily fluids. Exosomes contain a diversity of proteins, mRNAs, and non-coding RNAs, including microRNAs, long non-coding RNAs, piRNAs, circular RNAs, tsRNAs, and ribosomal RNAs, which are delivered to neighboring cells or even transported to distant sites. Exosomes have been associated with the tumorigenesis of OSCC, promote the proliferation, colonization, and metastasis of OSCC by transferring their contents to the target cells. Furthermore, exosomes are involved in the regulation of the tumor microenvironment to transform conditions favoring cancer progression in vivo. In this review, we summarize the crucial role of exosomes in the tumorigenesis and progression of OSCC and discuss the potential clinical application of exosomes in OSCC treatment.

Circulating Non-Coding RNAs in Head and Neck Cancer: Roles in Diagnosis, Prognosis, and Therapy Monitoring

Head and neck cancer (HNC), the seventh most common form of cancer worldwide, is a group of epithelial malignancies affecting sites in the upper aerodigestive tract. The 5-year overall survival for patients with HNC has stayed around 40–50% for decades, with mortality being attributable mainly to late diagnosis and recurrence. Recently, non-coding RNAs, including tRNA halves, YRNA fragments, microRNAs (miRNAs), and long non-coding RNAs (lncRNAs), have been identified in the blood and saliva of patients diagnosed with HNC. These observations have recently fueled the study of their potential use in early detection, diagnosis, and risk assessment. The present review focuses on recent insights and the potential impact that circulating non-coding RNA evaluation may have on clinical decision-making in the management of HNC.

MicroRNA profile in the squamous cell carcinoma: prognostic and diagnostic roles

Head and neck squamous cell carcinomas (HNSCCs) are human malignancies associated with both genetic and environmental factors. MicroRNAs (miRNAs) as a group of small non-coding RNAs have prominent roles in the development of this kind of cancer. Expressions of several miRNAs have been demonstrated to be increased in HNSCC samples vs. non-malignant tissues. In silico prediction tools and functional analyses have confirmed the function of some miRNAs in the modulation of cancer-associated targets, thus indicating these miRNAs as onco-miRs. Moreover, numerous miRNAs have been down-regulated in HNSCC samples. Their targets mostly enhance cell proliferation or inhibit apoptosis. miRNAs signature has practical implications in the diagnosis, staging, and management of HNSC. Most notably, numerous miRNAs have been shown to alter response of tumor cells to anti-cancer drugs such as cisplatin and doxorubicin. Circulating levels of these small transcripts have been suggested as promising biomarkers for diagnosis of HNSCC. In the present manuscript, we sum up the available literature regarding the miRNAs signature in HNSCC and their role as diagnostic/prognostic biomarkers.

Assessment of serum synuclein-γ and squamous cell carcinoma antigen as diagnostic biomarkers in patients with oral squamous cell carcinoma and oral potentially malignant disorders

BACKGROUND

Clinical diagnosis and monitoring are crucial to reduce the mortality from oral squamous cell carcinoma (OSCC) and oral potentially malignant disorders (OPMDs). It has been demonstrated that synuclein-γ (SNCG) and squamous cell carcinoma antigen (SCCAg) are highly expressed in patients with OSCC and perhaps participate in OSCC progression. This study analyzed the levels of serum SNCG and SCCAg in OSCC, OPMD, and control patients, and evaluated the diagnostic and clinical value of single and combined detection of serum SNCG and SCCAg in OSCC and OPMDs.

PATIENTS AND METHODS

Serum samples were collected from 197 patients including 87 patients with OSCC, 30 patients with OPMDs, and 80 healthy volunteers as controls. Enzyme-linked immunosorbent assay and statistical analysis were utilized to determine SNCG and SCCAg levels in serum.

RESULTS

The levels of SNCG and SCCAg in serum were significantly higher in OSCC compared with OPMDs and controls. There was a correlation between SNCG level and ethnicity, and SCCAg was correlated with differentiation. Furthermore, the area under the curves, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of combined detection of SNCG and SCCAg were better than any single detection.

CONCLUSION

The combined detection of SNCG and SCCAg in serum could become a new standard method to distinguish between OSCC and OPMDs and improve diagnostic performance for OSCC.

Blood-based circulating microRNAs as potential biomarkers for predicting the prognosis of head and neck cancer-a systematic review

OBJECTIVE

The aim of the present study was to systematically review the role of circulating miRNAs as potential prognostic biomarkers in head and neck cancer patients.

MATERIALS AND METHODS

PubMed, EMBASE, Scopus, Web of Science, and gray literature from January 1990 up to and including September 2019 were searched. The study selection was performed by two independent reviewers according to eligibility criteria.

RESULTS

A total of 13 studies that met the eligibility criteria were included. Significant number of studies were executed majorly in China and predominant number of them were case-control in nature. A total of 22 different miRNAs were found to be concomitant with very poor prognosis in cancers of the head and neck region. Of these, eighteen miRNAs (miR-375, miR-1234, miR-103, miR-638, miR-200b-3p, miR-191-5p, miR-24-3p, miR-572, miR-483-5p, miR-20a, miR-22, miR-29a, miR-29b, mir-let-7c, miR-17, miR-374b-5p, miR-425-5p, and miR-196a) were upregulated and four miRNAs (miR-9, miR-29c, miR-223, and miR-187∗) were downregulated. The hazard ratio (HR) ranged from twofold to fivefold.

CONCLUSION

Based on the results, circulating miRNA may assist in the prediction of prognosis of head and neck cancer. Further multi-center randomized controlled clinical trials with large sample size are required to validate the results of the present review.

CLINICAL RELEVANCE

Decoding the circulating miRNA profile could aid in accurate prognostication of head and neck cancer.

The roles of microRNAs in the stemness of oral cancer cells

Oral cancer (OC), which is the most common form of head and neck cancers, has one of the lowest (~50%) overall 5-year survival rates. The main reasons for this high mortality rate are diagnosis of OC in advanced stages in most patients and spread to distant organs via lymph node metastasis. Many studies have shown that a small population of cells within the tumor plays vital roles in the initiation, progression, and metastasis of the tumor, resistance to chemotherapeutic agents, and recurrence. These cells, identified as cancer stem cells (CSCs), are the main reasons for the failure of current treatment modalities. Deregulated expressions of microRNAs are closely related to tumor prognosis, metastasis and drug resistance. In addition, microRNAs play important roles in regulating the functions of CSCs. Until now, the roles of microRNAs in the acquisition and maintenance of OC stemness have not been elucidated in detail yet. Here in this review, we summarized significant findings and the latest literature to better understand the involvement of CSCs in association with dysregulated microRNAs in oral carcinogenesis. Possible roles of these microRNAs in acquisition and maintenance of CSCs features during OC pathogenesis were summarized.

miR-483-5p promotes esophageal cancer progression by targeting KCNQ1

OBJECTIVES

miR-483-5p has been reported to be an oncogene of various cancers, but its functional and regulatory mechanisms in esophageal cancer (EC) remain unclear. This study aimed to investigate the functional and molecular mechanisms of miR-483-5p in EC so as to provide a theoretical basis for exploring the therapeutic target for EC.

METHODS

miRNA expression profiles were downloaded from the TCGA-ESCA dataset to screen the target miRNA. Real-time quantitative PCR was performed to detect the transcriptional levels of miR-483-5p and KCNQ1 in EC cells. Western blot was conducted to determine the protein expression of KCNQ1. Cell Counting Kit-8 assay was carried out to assess cell proliferation. Transwell assay was performed to evaluate cell migration and invasion. Dual-luciferase reporter assay was conducted to verify the targeting relationship between miR-483-5p and KCNQ1.

RESULTS

miR-483-5p was up-regulated in EC cells and could bind to the 3'-untranslational region of KCNQ1. Over-expressing miR-483-5p suppressed KCNQ1 expression. Besides, miR-483-5p over-expression facilitated EC cell proliferation, migration and invasion, while its down-regulation triggered opposite result. Over-expressing miR-483-5p and KCNQ1 simultaneously could weaken the promoting effect of miR-483-5p over-expression on EC cell proliferation, migration and invasion.

CONCLUSION

miR-483-5p as an oncogene facilitated EC cell proliferation, migration and invasion by targeted silencing KCNQ1, which is likely to provide a basis for further exploring the molecular mechanism of EC progression.

Application of salivary noncoding microRNAs for the diagnosis of oral cancers

Oral cancer is on the rise globally and survival rates, despite improvements in clinical care, have not significantly improved. Early detection followed by immediate intervention is key to improving patient outcomes. The use of biomarkers has changed the diagnostic landscape for many cancers. For oral cancers, visual inspection followed by a tissue biopsy is standard practice. The discovery of microRNAs as potential biomarkers has attracted clinical interest but several challenges remain. These microRNAs can be found in bodily fluids such as blood and saliva which have been investigated as potential sources of biomarker discovery. As oral cancer is localized within the oral cavity, saliva may contain clinically relevant molecular markers for disease detection. Our review provides an outline of the current advances for the application of salivary microRNAs in oral cancer. We also provide a technical guide for the processing of salivary RNAs to ensure accurate clinical measurement and validation.

Functional Landscape of Dysregulated MicroRNAs in Oral Squamous Cell Carcinoma: Clinical Implications

MicroRNA (miRNA) dysregulation is associated with the pathogenesis of oral squamous cell carcinoma (OSCC), and its elucidation could potentially provide information on patient outcome. A growing body of translational research on miRNA biology is focusing on precision oncology, aiming to decode the miRNA regulatory network in the development and progression of cancer. Tissue-specific expression and stable presence in all body fluids are unique features of miRNAs, which could be potentially exploited in the clinical setting. Recent understanding of miRNA properties has led them to be useful, attractive, and potential tools either as biomarkers (distinct miRNA expression signature) for diagnosis and prognostic outcomes or as targets for novel therapeutic entities, enabling personalized treatment for OSCC. In this review, we discuss recent research on different aspects of alterations in miRNA profiles along with their clinical significance and strive to identify probable potential miRNA biomarkers for diagnosis and prognosis of OSCC. We also discuss the current understanding and scope of development of miRNA-based therapeutics against OSCC.

Cell-Free microRNAs as Potential Oral Cancer Biomarkers: From Diagnosis to Therapy

Oral cavity cancer is the most frequent malignancy of the head and neck. Unfortunately, despite educational interventions for prevention and early diagnosis, oral cancer patients are often diagnosed in advanced stages associated with poor prognosis and life expectancy. Therefore, there is an urgent need to find noninvasive biomarkers to improve early detection of this tumor. Liquid biopsy has emerged as a valuable tool in medical oncology which provides new horizons for improving clinical decision making. Notably, cell-free microRNAs (miRNAs), a class of short non-coding RNAs, are emerging as novel noninvasive cancer biomarkers. Here, we provide an overview of the potential clinical application of cell-free miRNAs as diagnostic, prognostic, and therapeutic biomarkers in oral cancer.

miRNAs in liquid biopsy for oral squamous cell carcinoma diagnosis: Systematic review and meta-analysis

Oral squamous cell carcinoma (OSCC) is often diagnosed at advanced stages and is associated with poor survival rates. Increasing evidence suggests that microRNAs (miRNAs) present in liquid biopsies could be potential biomarkers for non-invasive OSCC diagnosis. Here, we performed a comprehensive meta-analysis to evaluate the overall diagnostic accuracy of blood and salivary miRNAs in detecting OSCC. A literature search using PubMed EMBASE, Web of Science, LILACS, Scopus, and the Cochrane Library was undertaken up to February 2019. Study quality was assessed with the Quality Assessment for Studies of Diagnostic Accuracy-2, and sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and their corresponding 95% confidence intervals (CIs) were calculated using a bivariate random-effect meta-analysis model. Meta-regression and subgroup analyses were performed to assess the heterogeneity. Twenty-five study units from 16 articles with 2562 subjects were included in this meta-analysis. The pooled sensitivity and specificity of blood and salivary miRNAs in the diagnosis of OSCC were 0.78 (95% CI: 0.76-0.80) and 0.82 (95% CI: 0.79-0.84), respectively, and the pooled positive and negative likelihood ratios were 4.31 (95% CI: 3.38-5.51) and 0.25 (95% CI: 0.20-0.32), respectively. The overall area under the curve was 0.91 (95% CI: 0.88-0.93), with a diagnostic odds ratio of 21.46 (95% CI: 13.37-34.45). These findings provide evidence regarding the potential clinical application of blood and salivary miRNAs as a novel, non-invasive, and accurate diagnostic tool for OSCC.

Circulating MicroRNAs as Prognostic Molecular Biomarkers in Human Head and Neck Cancer: A Systematic Review and Meta-Analysis

Background

Circulating microRNAs (miRNAs) are potential molecular biomarkers for cancer detection; however, little is known about their prognostic role in head and neck cancer. This current study is aimed at evaluating the role of novel miRNAs in the survival of head and neck cancer patients.

Materials and Methods

We performed a systematic literature search using online databases for articles published between December 2006 and February 2019. A meta-analysis was conducted to assess the correlation between miRNA expressions and overall survival (OS) among the selected head and neck cancer studies. After multilevel screening by reviewers, meta-analysis was performed using hazard ratios (HR) and associated 95% confidence interval (CI) of survival to calculate a pooled effect size.

Result

A total of 1577 patients across 13 studies were included in the literature review, with 18 miRNAs upregulated and 4 miRNAs downregulated predicting a poor overall survival. The forest plot generated using cumulated survival data resulted in a pooled HR value of 2.943 (95% CI: 2.394-3.618) indicating a strong association of dysregulated miRNA expression with a poor outcome. Only 2 miRNAs—low levels of miR-9 and high levels of miR-483-5p—were observed in two studies, both showing a significant association with overall cancer survival.

Conclusion

To our knowledge, this is the first comprehensive systematic review and meta-analysis that examines the prognostic role of circulating miRNAs from blood in head and neck cancer patients. The combined effect estimates a HR across multiple studies and also supports the previous individual findings that an alteration in miRNA expression is highly associated with poor prognosis. This has the potential to use serum and/or plasma miRNAs as biomarkers and become novel tools for predicting the prognosis of head and neck cancer patients in the near future.

Extracellular miRNAs as Biomarkers of Head and Neck Cancer Progression and Metastasis

Head and neck squamous cell carcinomas (HNSCCs) contribute to over 300,000 deaths every year worldwide. Although the survival rates have improved in some groups of patients, mostly due to new treatment options and the increasing percentage of human papillomavirus (HPV)-related cancers, local recurrences and second primary tumors remain a great challenge for the clinicians. Presently, there is no biomarker for patient surveillance that could help identify patients with HNSCC that are more likely to experience a relapse or early progression, potentially requiring closer follow-up or salvage treatment. MicoRNAs (miRNAs) are non-coding RNA molecules that posttranscriptionally modulate gene expression. They are highly stable and their level can be measured in biofluids including serum, plasma, and saliva, enabling quick results and allowing for repeated analysis during and after the completion of therapy. This has cemented the role of miRNAs as biomarkers with a huge potential in oncology. Since altered miRNA expression was described in HNSCC and many miRNAs play a role in radio- and chemotherapy resistance, cancer progression, and metastasis, they can be utilized as biomarkers of these phenomena. This review outlines recent discoveries in the field of extracellular miRNA-based biomarkers of HNSCC progression and metastasis, with a special focus on HPV-related cancers and radioresistance.

Prospective applications of microRNAs in oral cancer

MicroRNAs (miRNAs) are non-coding RNA molecules that are generally encoded by endogenous genes and exert suppressive effects on post-transcriptional regulation of their target genes by translation repression or degradation of mRNA. This subsequently mediates activation or blocking of downstream signaling pathways associated with oral malignancies. Aberrant levels of certain miRNAs have been identified in cell experiments, clinical carcinomatous specimens, saliva, serum or plasma samples of patients with oral malignancies. miRNAs are associated with multiple aspects of oral cancer, including tumor growth, cellular proliferation, apoptosis, migration, invasion, metastasis, glycometabolism, radiosensitivity and chemosensitivity. miRNAs have the potential to be used in clinical applications as minimally invasive or non-invasive tools for early diagnosis and prognosis by the detection of serum, plasma and saliva levels, and may provide a new ancillary or additional reference index of traditional pathological grading and clinical staging. Furthermore, miRNAs may be used as prognostic biomarkers or targets for novel therapies for oral cancer.

Prognostic Value of miRNAs in Head and Neck Cancers: A Comprehensive Systematic and Meta-Analysis

Head and Neck Cancer (HNC) is the sixth most common type of cancer across the globe, with more than 300,000 deaths each year, globally. However, there are currently no standardised molecular markers that assist in determining HNC prognosis. The literature for this systematic review and meta-analysis were sourced from multiple bibliographic databases. This review followed PRISMA guidelines. The Hazard Ratio (HR) was selected as the effect size metric to independently assess overall survival (OS), disease-free survival (DFS), and prognosis. Subgroup analysis was performed for individual highly represented miRNA. A total of 6843 patients across 50 studies were included in the systematic review and 34 studies were included in the meta-analysis. Studies across 12 countries were assessed, with China representing 36.7% of all included studies. The analysis of the survival endpoints of OS and DFS were conducted separately, with the overall pooled effect size (HR) for each being 1.825 (95% CI 1.527–2.181; p < 0.05) and 2.596 (95% CI 1.917–3.515; p < 0.05), respectively. Subgroup analysis was conducted for impact of miR-21, 200b, 155, 18a, 34c-5p, 125b, 20a and 375 on OS, and miR-21 and 34a on DFS. The pooled results were found to be statistically significant for both OS and DFS. The meta-analysis indicated that miRNA alterations can account for an 82.5% decrease in OS probability and a 159.6% decrease in DFS probability. These results indicate that miRNAs have potential clinical value as prognostic biomarkers in HNC, with miR-21, 125b, 34c-5p and 18a, in particular, showing great potential as prognostic molecular markers. Further large scale cohort studies focusing on these miRNAs are recommended to verify the clinical utility of these markers individually and/or in combination.

Circulating microRNAs in head and neck cancer: a scoping review of methods

Circulating microRNAs have been described as head and neck cancer biomarkers in multiple anatomical subsites including the oral cavity, nasopharynx, larynx, salivary glands and the skin. While there is an expanding volume of published literature showing the significance of individual or panels of microRNAs, the clinical validation of candidate biomarkers is lacking. The various methods used to collect, store, process and interpret these microRNAs are likely introducing bias and contributing to the inconsistent results. A systematic scoping review was conducted using PRISMA standards to identify published English literature between 2007 and 2018. Pubmed and EMBASE databases were searched using specific keyword combinations related to head and neck cancer, circulating samples (whole blood, plasma or serum) and microRNA. Following the title and abstract review, two primary authors appraised the articles for their suitability to include in the review based on the detail of methodological descriptions. Thirty suitable articles were identified relating to nasopharyngeal carcinoma, oral cavity, oropharyngeal and laryngeal squamous cell carcinoma as well as primary salivary gland malignancies. Comprehensive methodological analysis identified poor reporting of detailed methodology, variations in collection, storage, pre-processing, RNA isolation and relative quantification including normalisation method. We recommend standardising the pre-processing, RNA isolation, normalisation and relative quantitation steps at biomarker discovery phase. Such standardisation would allow for bias minimisation and effective progression into clinical validation phases.

Serum miR-626 and miR-5100 are Promising Prognosis Predictors for Oral Squamous Cell Carcinoma

Although serum microRNAs (miRNAs) are currently being considered as promising noninvasive biomarkers for cancers, their role in the prognosis of oral squamous cell carcinoma (OSCC) has not been elucidated. Here we aimed to identify serum miRNA biomarkers that could be used as prognosis predictors of OSCC.

Methods: A cohort of 260 serum miRNA samples was assessed in a three-step approach that included a screening stage, a training stage, and a testing stage. The correlation between prognosis of OSCC and the miRNAs expression was comprehensively analyzed.

Results: A two-miRNA signature involving miR-626 and miR-5100 has been developed. Patients defined to be high-risk group by the two-miRNA signature had significantly shortened median survival time compared with the low-risk group. In multivariate analysis, this two-miRNA signature was independently predictive of survival, and achieved a superior predictive value compared with that of traditional clinicopathologic factors such as pathology grade as well as tumor and node metastasis (TNM) stage. An integrated prognostic model combining the TNM stage and miRNA signature displayed the highest prognostic performance (AUC value: 0.787, specificity: 0.884, sensitivity: 0.573) compared to the TNM stage-alone (AUC value: 0.630, specificity: 0.526, sensitivity: 0.733) or miRNA signature-alone model (AUC value: 0.771, specificity: 0.768, sensitivity: 0.773). In addition, we found that OSCC tumor cells not only expressed a high level of these two miRNAs, but also secreted certain miRNAs into the extracellular environment, suggesting these miRNAs may originate from tumor cells.

Conclusion: In our study, we established a two-miRNA signature that was strongly and independently associated with prognosis in OSCC, and may serve as a promising prognosis predictor.

Liquid biopsy: miRNA as a potential biomarker in oral cancer

Oral cancer is one of the leading cancers in South-Asian countries. Despite the easy access of the oral cavity, the detection and five year survival rates of OSCC patients are dismal. Identification of non-invasive biomarkers to determine the progression and recurrence of OSCC could be of immense help to patients. Recent studies on oral cancer suggest the importance of non-invasive biomarker development. Micro-RNAs (miRNAs) are one of the important components of the cell-free nucleic acids available in different body fluids. Here, we have reviewed the current understanding of circulating miRNAs as non-invasive biomarkers in different body fluids of oral cancer patients. A number of circulating miRNAs are found to be common in the body fluids of OSCC patients, while many of these are study specific, the possible sources of this variability could be due to differences in sample processing, assay procedure, clinical stage of the disease, oral habit and environmental factors. The prognostic and therapeutic significance of these circulating miRNAs are suggested by several studies. Mir-371, mir-150, mir-21 and mir-7d were found to be potential prognostic markers, while mir-134, mir-146a, mir-338 and mir-371 were associated with metastases. The prognostic markers, mir-21 and mir-7d were also found to be significantly correlated with resistance to chemotherapy, while mir-375, mir-196 and mir-125b were significantly correlated with sensitivity to radiotherapy. Despite the promising roles of circulating miRNAs, challenges still remain in unravelling the exact regulation of these miRNAs before using them for targeted therapy.

Apurinic/Apyrimidinic Endonuclease 1/Redox Factor-1 Could Serve as a Potential Serological Biomarker for the Diagnosis and Prognosis of Oral Squamous Cell Carcinoma

PURPOSE

Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein that shows elevated expression in many cancers, including oral squamous cell carcinoma (OSCC). However, the serum APE1/REF-1 level remains unknown in such patients. The purpose of the present study was to estimate the serum APE/Ref-1 levels in patients with OSCC and measure its association with the diagnosis, clinicopathologic features, and prognosis of OSCC.

PATIENTS AND METHODS

A total of 98 primary patients with OSCC and 109 age- or gender-matched normal controls were included in our case-control study. The predictor variable was the serum APE1/Ref-1 level, which was measured using an enzyme-linked immunosorbent assay. The outcome variables included diagnosis, clinicopathologic characteristics, treatment response, and OSCC prognosis. The optimal cutoff points of serum APE1/Ref-1 were identified using the X-tile program with minimum P values. Prognostic factors were evaluated using univariate and multivariate Cox regression models.

RESULTS

The average patient and control age was 51.6 ± 8.7 years (63 men; 35 women) and 52.4 ± 10.3 years (67 men; 42 women), respectively. The serum APE1/Ref-1 level was significantly greater in patients with OSCC than that in the controls (4.56 ± 1.09 ng/mL vs 3.18 ± 0.88 ng/mL; P < .01). Much higher serum APE1/Ref-1 levels were observed in those with OSCC with late TNM stage, lymph node metastases, and worse pathologic differentiation. The receiver operating characteristic curve analysis illustrated that the serum APE1/Ref-1 level was a potential biomarker for differentiating OSCC, with an area under the curve of 0.83 (95% confidence interval, 0.78 to 0.88; sensitivity, 0.87; specificity, 0.68). The log-rank analysis revealed that patients with OSCC and a low APE1/Ref-1 level experienced longer disease-free survival after postoperative cisplatin chemotherapy and overall survival (P < .05).

CONCLUSIONS

An elevated APE1/Ref-1 level might serve as a novel potential diagnostic biomarker for OSCC and can reflect the treatment response to cisplatin chemotherapy and prognosis.

Biomarkers: paving stones on the road towards the personalized precision medicine for oral squamous cell carcinoma

Traditional therapeutics have encountered a bottleneck caused by diagnosis delay and subjective and unreliable assessment. Biomarkers can overcome this bottleneck and guide us toward personalized precision medicine for oral squamous cell carcinoma. To achieve this, it is important to efficiently and accurately screen out specific biomarkers from among the huge number of molecules. Progress in omics-based high-throughput technology has laid a solid foundation for biomarker discovery. With credible and systemic biomarker models, more precise and personalized diagnosis and assessment would be achieved and patients would be more likely to be cured and have a higher quality of life. However, this is not straightforward owing to the complexity of molecules involved in tumorigenesis. In this context, there is a need to focus on tumor heterogeneity and homogeneity, which are discussed in detail. In this review, we aim to provide an understanding of biomarker discovery and application for precision medicine of oral squamous cell carcinoma, and have a strong belief that biomarker will pave the road toward future precision medicine.

The Glucose-Regulated MiR-483-3p Influences Key Signaling Pathways in Cancer

The hsa-mir-483 gene, located within the IGF2 locus, transcribes for two mature microRNAs, miR-483-5p and miR-483-3p. This gene, whose regulation is mediated by the the CTNNB1/USF1 complex, shows an independent expression from its host gene IGF2. The miR-483-3p affects the Wnt/β-catenin, the TGF-β, and the TP53 signaling pathways by targeting several genes as CTNNB1, SMAD4, IGF1, and BBC3. Accordingly, miR-483-3p is associated with various tissues specific physiological properties as insulin and melanin production, as well as with cellular physiological functions such as wounding, differentiation, proliferation, and survival. Deregulation of miR-483-3p is observed in different types of cancer, and its overexpression can inhibit the pro-apoptotic pathway induced by the TP53 target effectors. As a result, the oncogenic characteristics of miR-483-3p are linked to the effect of some of the most relevant cancer-related genes, TP53 and CTNNB1, as well as to one of the most important cancer hallmark: the aberrant glucose metabolism of tumor cells. In this review, we summarize the recent findings regarding the miR-483-3p, to elucidate its functional role in physiological and pathological contexts, focusing overall on its involvement in cancer and in the TP53 pathway.

MicroRNA-22 suppresses cell proliferation, migration and invasion in oral squamous cell carcinoma by targeting NLRP3

MicroRNAs (miRNAs) have been implicated as important regulators of carcinogenesis and tumor development. Recently, microRNA-22 (miR-22) has been reported to be a cancer-related miRNA in several types of tumors. In this study, we aimed to investigate the role of miR-22 in oral squamous cell carcinoma (OSCC). We found that miR-22 expression was significantly decreased in OSCC tissues compared with that in the adjacent noncancerous tissues. Furthermore, lentivirus-mediated miR-22 overexpression markedly reduced OSCC cell viability, migration and invasion, whereas miR-22 inhibitor promoted these parameters. Mechanistically, NLR family pyrin domain containing three (NLRP3) was identified as a direct target of miR-22. miR-22 expression was inversely correlated with NLRP3 expression both in OSCC tissues and cell lines. Moreover, overexpression of miR-22 in OSCC cells could reverse the tumor-promoting effect of the activated NLRP3 inflammasome and vice versus. Therefore, our results indicate that miR-22 may play a suppressive role in OSCC by targeting NLRP3, which offer new insights into the molecular mechanisms of the growth and metastasis of OSCC.

Predicting Value of ALCAM as a Target Gene of microRNA-483-5p in Patients with Early Recurrence in Hepatocellular Carcinoma

The long-term survival rate of hepatocellular carcinoma (HCC) is poor. One of the reasons for the poor rate of survival is the high rate of recurrence caused by intrahepatic metastas is that adversely affects long-term outcome. Many studies have indicated that microRNAs play an important role in HCC, but there has been no research of clonal origins on recurrent HCC (RHCC) by analzing microRNAs. In the present study, we found that miR-483-5p was significantly upregulated in RHCC tissues of short-term recurrence (≤ 2 years) by miRNA microarray screening, and can significantly promote migration and invasion of HCC cells in vitro and increase intrahepatic metastasis in nude mice in vivo. Furthermore, we demonstrated that activated leukocyte cell adhesion molecule (ALCAM), which significantly suppressed migration and invasion of HCC cells, was a direct target of miR-483-5p, and the re-introduction of ALCAM expression could antagonize the promoting effects of miR-483-5p on the capacity of HCC cells for migration and invasion. In addition, expression level of ALCAM was negatively correlated with microvascular invasion and tumor size recognized as prognostic factors. The cases which were negative for ALCAM expression had shorter time to recurrence than positive cases, and univariate and multivariate survival analyses showed that ALCAM was an independent risk factor of HCC recurrence. qRT-PCR and Western blotting showed that the expression of EMT related genes (MMP-2, MMP-9, E-caherin and vimentin) significantly changed as a result of interfering or overexpression of ALCAM, and ALCAM was significantly associated with EMT in HCC. These results suggest that the miR-483-5p/ALCAM axis is an important regulator in invasion and metastasis and biomarker for recurrence risk assessment of HCC.