Clinical and histopathologic parameters in survival of oral squamous cell carcinoma

Mitochondrial DNA is a sensitive surrogate and oxidative stress target in oral cancer cells

Cellular oxidative stress mediated by intrinsic and/or extrinsic reactive oxygen species (ROS) is associated with disease pathogenesis. Oxidative DNA damage can naturally be substituted by mitochondrial DNA (mtDNA), leading to base lesion/strand break formation, copy number changes, and mutations. In this study, we devised a single test for the sensitive quantification of acute mtDNA damage, repair, and copy number changes using supercoiling-sensitive quantitative PCR (ss-qPCR) and examined how oxidative stress-related mtDNA damage responses occur in oral cancer cells. We observed that exogenous hydrogen peroxide (H2O2) induced dynamic mtDNA damage responses, as reflected by early structural DNA damage, followed by DNA repair if damage did not exceed a particular threshold. However, high oxidative stress levels induced persistent mtDNA damage and caused a 5-30-fold depletion in mtDNA copy numbers over late responses. This dramatic depletion was associated with significant growth arrest and apoptosis, suggesting persistent functional consequences. Moreover, oral cancer cells responded differentially to oxidative injury when compared with normal cells, and different ROS species triggered different biological consequences under stress conditions. In conclusion, we developed a new method for the sensitive detection of mtDNA damage and copy number changes, with exogenous H2O2 inducing dynamic mtDNA damage responses associated with functional changes in stressed cancer cells. Finally, our method can help characterize oxidative DNA damage in cancer and other human diseases.

Comprehensive survival analysis of oral squamous cell carcinoma patients undergoing initial radical surgery

OBJECTIVE

This study was designed to evaluate the five-year overall survival (OS) rate and postoperative survival time of patients diagnosed with oral squamous cell carcinoma (OSCC), as well as examine the clinical and pathological factors influencing survival outcomes in OSCC patients.

METHODS

Data were collected from OSCC patients who underwent their first radical surgical intervention in the Department of Maxillofacial Surgery at the First Affiliated Hospital of Chongqing Medical University between April 2014 and December 2016. Follow-up was conducted until March 2022.

RESULTS

The study included a total of 162 patients. The observed 5-year OS rate was 59.3%. Approximately 45.7% of OSCC patients experienced postoperative recurrence or metastasis, with a 5-year overall disease-free survival rate of 49.4%. There was no significant difference in the impact of sex, age, smoking, alcohol consumption, primary tumour location, depth of invasion or primary tumour size on the 5-year survival rate (p > 0.05). Univariate analysis revealed that clinical stage (Hazard Ratio = 2.239, p = 0.004), perineural invasion (PNI) (Hazard Ratio = 1.712, p = 0.03), lymph node metastasis (pN) (Hazard Ratio = 2.119, p = 0.002), pathological differentiation (Hazard Ratio = 2.715, p < 0.001), and recurrence or metastasis (Hazard Ratio = 10.02, p < 0.001) were significant factors influencing survival. Multivariate analysis further indicated that pathological differentiation (Hazard Ratio = 2.291, p = 0.001), PNI (Hazard Ratio = 1.765, p = 0.031) and recurrence or metastasis (Hazard Ratio = 9.256, p < 0.001) were independent risk factors of survival. Intriguingly, 11 OSCC patients were diagnosed with oesophageal squamous cell carcinoma (ESCC) within 1-4 years following surgery.

CONCLUSION

The survival prognosis of OSCC patients is significantly associated with clinical stage, PNI, lymph node metastasis, pathological differentiation, and recurrence or metastasis. Pathological differentiation, PNI and recurrence or metastasis are independent risk factors affecting survival. Routine clinical screening for ESCC may be recommended for OSCC patients with a history of alcohol consumption and tobacco use.

Impact of histopathological parameters in prognosis of oral squamous cell carcinoma

OBJECTIVE

Squamous cell carcinomas comprise approximately 90% of all oral malignancies. There is a wide geographical variation in the incidence of oral cancer, with South and South East Asia (SSEA) accounting for almost two third of new cases. The prognosis of oral cancer is influenced by a vast array of factors including demographic, clinical, histopathological and molecular factors. The objective this review is to analyse the impact of histopathological features assessed in hematoxylin and eosin stained sections on the prognosis of OSCC.

MATERIALS AND METHODS

Medline and Scopus data base search was performed in order to identify related articles on histopathological parameters in predicting prognosis of oral squamous cell carcinoma. The primary emphasis is on the studies conducted in SSEA, with an accompanying comparison of their findings with those from research conducted in other parts of the world.

RESULTS

It has been shown that the number of studies conducted in SSEA is not proportionate to the high prevalence of Oral Cancer in the region. There is no significant difference between the findings from SSEA compared to the rest of the world. It is clearly shown that most histopathological parameters can be accurately used to predict nodal metastasis and prognosis.

CONCLUSIONS

Histopathological parameters can be used reliably in planning treatment of Oral cancer. Clinicians should combine clinical and histopathological parameters in drawing treatment plan for Oral Cancer.

HPV and Other Risk Factors Involved in Pharyngeal Neoplasm-Clinical and Morphopathological Correlations in the Southwestern Region of Romania

Oropharyngeal squamous cell carcinoma (OPSCC) development is strongly associated with risk factors like smoking, chronic alcohol consumption, and the living environment, but also chronic human papilloma virus (HPV) infection, which can trigger cascade cellular changes leading to a neoplastic transformation. The prevalence of these factors differs among different world regions, and the prevention, diagnosis, and prognosis of OPSCC are highly dependent on them. We performed a retrospective study on 406 patients diagnosed with OPSCC in our region that were classified according to the tumor type, localization and diagnosis stage, demographic characteristics, risk factors, and histological and immunohistochemical features. We found that most of the patients were men from urban areas with a smoking habit, while most of the women in our study were diagnosed with tonsillar OPSCC and had a history of chronic alcoholism. During the immunohistochemical study, we analyzed the tumor immunoreactivity against anti-p16 and anti-HPV antibodies as markers of HPV involvement in tumor progression, as well as the correlation with the percentage of intratumoral nuclei immunomarked with the anti-Ki 67 antibody in serial samples. We observed that the percentage of Ki67-positive nuclei increased proportionally with the presence of intratumoral HPV; thus, active HPV infection leads to an increase in the rate of tumor progression. Our results support the implementation of strategies for OPSCC prevention and early diagnosis and can be a starting point for future studies aiming at adapting surgical and oncological treatment according to the HPV stage for better therapeutic results.

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.

Clinical implications of Cytokeratin 19 expression in patients with oral squamous cell carcinoma

Objective

This study was done to quantify the prevalence of high cytokeratin (CK) 19 expression in Indonesian oral squamous cell carcinoma (OSCC) patients and explore the prognostic role of CK19 in OSCC.

Methods

Clinical data and samples from 61 patients diagnosed with OSCC at a tertiary national referral hospital in Jakarta, Indonesia were analyzed in this retrospective cohort study. Immunohistochemical staining of CK19 was performed on all patients and its expression was scored using the H system. All patients were followed up for a minimum of 36 months after diagnosis. Comparative and survival analyses were performed.

Results

Twenty six point two percent of Indonesian OSCC patients had high CK19 expression. There were no differences in clinicopathological characteristics between patients with low and high CK19 expression. The 3-year overall survival (OS) of our cohort was 11.5%. Patients with high CK19 expression had lower 3-year OS compared to patients with low CK19 expression, even if the difference in OS was not statistically significant. Keratinization was an independent prognostic factor for survival in multivariate regression analysis.

Conclusions

Data obtained here indicate a possible prognostic role of CK19 in OSCC. This prognostic role should be confirmed in larger series.

Epidemiology of Oral Cancer in Taiwan: A Population-Based Cancer Registry Study

Oral cancer (OC) is one of the most common cancers worldwide, and its incidence has regional differences. In this study, the cancer registry database obtained from 1980 to 2019 was used to analyze the characteristic of incidence of OC by average annual percentage change (AAPC) and an age–period–cohort model. Spearman’s correlation was used to analyze the relationship between the age-standard incidence rates (ASR) of OC and related risk factors. Our results showed that the ASR of OC increased from 4.19 to 27.19 per 100,000 population with an AAPC of 5.1% (95% CI = 3.9–6.3, p value < 0.001) in men and from 1.16 to 2.8 per 100,000 population with an AAPC of 3.1% (95% CI = 2.6–3.6, p value < 0.001) in women between 1980–1984 and 2015–2019. The age–period–cohort model reported a trend of rising then declining for the rate ratio in men, with peaks occurring in the 1975 cohort, with a rate ratio of 6.80. The trend of incidence of oral cancer was related to changes in the consumption of cigarettes and alcohol and production of betel quid, with r values of 0.952, 0.979 and 0.963, respectively (all p values < 0.001). We strongly suggest avoiding these risk factors in order to prevent OC.

Interplay of adherens junctions and matrix proteolysis determines the invasive pattern and growth of squamous cell carcinoma

Cancers, such as squamous cell carcinoma, frequently invade as multicellular units. However, these invading units can be organised in a variety of ways, ranging from thin discontinuous strands to thick 'pushing' collectives. Here we employ an integrated experimental and computational approach to identify the factors that determine the mode of collective cancer cell invasion. We find that matrix proteolysis is linked to the formation of wide strands but has little effect on the maximum extent of invasion. Cell-cell junctions also favour wide strands, but our analysis also reveals a requirement for cell-cell junctions for efficient invasion in response to uniform directional cues. Unexpectedly, the ability to generate wide invasive strands is coupled to the ability to grow effectively when surrounded by extracellular matrix in three-dimensional assays. Combinatorial perturbation of both matrix proteolysis and cell-cell adhesion demonstrates that the most aggressive cancer behaviour, both in terms of invasion and growth, is achieved at high levels of cell-cell adhesion and high levels of proteolysis. Contrary to expectation, cells with canonical mesenchymal traits - no cell-cell junctions and high proteolysis - exhibit reduced growth and lymph node metastasis. Thus, we conclude that the ability of squamous cell carcinoma cells to invade effectively is also linked to their ability to generate space for proliferation in confined contexts. These data provide an explanation for the apparent advantage of retaining cell-cell junctions in squamous cell carcinomas.

Worst Pattern of Invasion as a Predictor of Nodal Metastasis in Early-Stage Oral Squamous Cell Carcinoma

About one-third of early stage oral cancer patients have occult nodal metastasis. High grade worst pattern of invasion (WPOI) is associated with an increased risk of nodal metastasis and poor prognosis. However, it still remains unanswered whether to perform an elective neck dissection for clinically node-negative disease or not. This study aims to evaluate the role of histological parameters including WPOI in predicting nodal metastasis in early-stage oral cancers. This analytical observational study comprised 100 patients of early-stage, node-negative, oral squamous cell carcinoma, admitted in the Surgical Oncology Department from April, 2018 till the sample size was reached. The socio-demographic data, clinical history, and findings of clinical and radiological examination were noted. The association of nodal metastasis with various histological parameters like tumour size, degree of differentiation, depth of invasion (DOI), WPOI, perineural invasion (PNI), lymphovascular invasion (LVI) and lymphocytic response was determined. SPSS 20.0 statistical tool; student's 't' test and chi-square tests were applied. While the buccal mucosa was the commonest site, the rate of occult metastasis was highest in the tongue. Nodal metastasis was not significantly associated with age, sex, smoking and primary site. While the nodal positivity was not significantly associated with tumour size, pathological stage, DOI, PNI and lymphocytic response, it was associated with LVI, degree of differentiation and WPOI. Increasing WPOI grade correlated significantly with the nodal stage, LVI and PNI, but not with DOI. WPOI is not only a significant predictor of occult nodal metastasis but can also be a novel therapeutic tool in the management of early-stage oral cancers. In patients with an aggressive WPOI pattern or other high-risk histological parameters, the neck can be addressed with either elective neck dissection or radiotherapy after wide excision of the primary tumor; otherwise, an active surveillance approach can be followed.

Patterns of Neck Nodal Metastasis from Oral Cavity Carcinoma

Nitin KhuntetaObjectives  The aim is to study the patterns of lymph node metastasis from various sites in oral cavity cancer and determine the risk factors for metastasis. Materials and Methods  It is a prospective observational study. The inclusion criteria were-245 patients of carcinoma buccal mucosa, anterior two-thirds of tongue, hard palate, oral surface of soft palate, floor of mouth, vestibule, and alveolus. The exclusion criteria were-patients who had received preoperative chemotherapy or radiotherapy and patients with recurrent disease. Statistical Methods  All data were analyzed using SPSS 18.0 and Graphpad prism 7 software for statistical analysis. Count data have been expressed as percentages (%). The χ ² test was used for univariate analysis of the risk factors of cervical lymph node metastasis. The odds ratio value (with 95% confidence interval) was used to express the risk of cervical lymph node metastasis. p -Value of <0.05 was considered as the difference with statistical significance. Results  The most common site involved was buccal mucosa. Patterned lymph node metastasis was seen in 93.5% cases. Skip metastasis was seen in 4.31% cases. Level I b was the most common site of nodal involvement for all primary subsites of oral cavity cancer. The incidence of positive nodes on histopathological analysis was highest in cases of lower alveolus (63.15%), followed by tongue. Conclusion  In our study, patterns of lymph node metastasis for oral cavity cancer were comparable to other studies with large number of subjects. The incidence of skip metastasis or aberrant status was low. On multivariate analysis, depth of invasion of tumor, pathologic grade, pathologic T stage, and morphologic type of growth were found to be independent predictors of risk for metastasis.

Involvement of AMPKα and MAPK-ERK/-JNK Signals in Docetaxel-Induced Human Tongue Squamous Cell Carcinoma Cell Apoptosis

Cancers of the oral cavity can develop in the anatomic area extending from the lip, gum, tongue, mouth, and to the palate. Histologically, about 85-90% of oral cavity cancers are of the type squamous cells carcinomas (SCCs). The incidence of oral tongue SCC is higher in the tongue than any other anatomic area of the oral cavity. Here, we investigated the therapeutic effects and molecular mechanisms of docetaxel, which is a paclitaxel antitumor agent, on the cell growth of a human tongue SCC-derived SAS cell line. The results showed that docetaxel (10-300 nM) induced cytotoxicity and caspase-3 activity in SAS cells. Moreover, docetaxel (100 nM) promoted the expression of apoptosis-related signaling molecules, including the cleavages of caspase-3, caspase-7, and poly (ADP-ribose) polymerase (PARP). In mitochondria, docetaxel (100 nM) decreased the mitochondrial membrane potential (MMP) and Bcl-2 mRNA and protein expression and increased cytosolic cytochrome c protein expression and Bax mRNA and protein expression. In terms of mitogen-activated protein kinase (MAPK) and adenosine monophosphate-activated protein kinase (AMPK) signaling, docetaxel increased the expression of phosphorylated (p)-extracellular signal-regulated kinase (ERK), p-c-Jun N-terminal kinase (JNK), and p-AMPKα protein expression but not p-p38 protein expression. Moreover, the increase in caspase-3/-7 activity and Bax protein expression and decreased Bcl-2 protein expression and MMP depolarization observed in docetaxel-treated SAS cells could be reversed by treatment with either SP600125 (a JNK inhibitor), PD98059 (an MEK1/2 (mitogen-activated protein kinase kinase 1/2) inhibitor), or compound c (an AMPK inhibitor). The docetaxel-induced increases in p-JNK, p-ERK, and p-AMPKα protein expression could also be reversed by treatment with either SP600125, PD98059, or compound c. These results indicate that docetaxel induces human tongue SCC cell apoptosis via interdependent MAPK-JNK, MAPK-ERK1/2, and AMPKα signaling pathways. Our results show that docetaxel could possibly exert a potent pharmacological effect on human oral tongue SCC cell growth.

Identifying Drug Targets of Oral Squamous Cell Carcinoma through a Systems Biology Method and Genome-Wide Microarray Data for Drug Discovery by Deep Learning and Drug Design Specifications

In this study, we provide a systems biology method to investigate the carcinogenic mechanism of oral squamous cell carcinoma (OSCC) in order to identify some important biomarkers as drug targets. Further, a systematic drug discovery method with a deep neural network (DNN)-based drug–target interaction (DTI) model and drug design specifications is proposed to design a potential multiple-molecule drug for the medical treatment of OSCC before clinical trials. First, we use big database mining to construct the candidate genome-wide genetic and epigenetic network (GWGEN) including a protein–protein interaction network (PPIN) and a gene regulatory network (GRN) for OSCC and non-OSCC. In the next step, real GWGENs are identified for OSCC and non-OSCC by system identification and system order detection methods based on the OSCC and non-OSCC microarray data, respectively. Then, the principal network projection (PNP) method was used to extract core GWGENs of OSCC and non-OSCC from real GWGENs of OSCC and non-OSCC, respectively. Afterward, core signaling pathways were constructed through the annotation of KEGG pathways, and then the carcinogenic mechanism of OSCC was investigated by comparing the core signal pathways and their downstream abnormal cellular functions of OSCC and non-OSCC. Consequently, HES1, TCF, NF-κB and SP1 are identified as significant biomarkers of OSCC. In order to discover multiple molecular drugs for these significant biomarkers (drug targets) of the carcinogenic mechanism of OSCC, we trained a DNN-based drug–target interaction (DTI) model by DTI databases to predict candidate drugs for these significant biomarkers. Finally, drug design specifications such as adequate drug regulation ability, low toxicity and high sensitivity are employed to filter out the appropriate molecular drugs metformin, gefitinib and gallic-acid to combine as a potential multiple-molecule drug for the therapeutic treatment of OSCC.

Clinicopathological characteristics predicting advanced stage and surgical margin invasion of oral squamous cell carcinoma: A single‑center study on 10 years of cancer registry data

The incidence profile of oral squamous cell carcinoma (OSCC) has not previously been comprehensively reported in Indonesia. The present study aimed to identify clinicopathological characteristics of patients with OSCC according to sex and age, to analyze histological differentiation patterns specific to tumor subsites, to highlight the role of lymphovascular invasion (LVI) in metastasis, and to develop a model to predict advanced stage and margin invasion. A retrospective cross-sectional study was performed using 581 medical records and pathological specimens from cancer registry data in the Dr Cipto Mangunkusumo Hospital (Jakarta, Indonesia), between January 2011 and December 2020. Clinicopathological characteristics were analyzed using parametric and non-parametric tests. Multivariate logistic regression analyses were performed for eligible parameters, identified using bivariate analysis, to predict advanced stage and margin invasion. Calibration of the prediction model was evaluated using the Hosmer-Lemeshow test, its discrimination value assessed using the receiver operating characteristic and area under the receiver operating characteristic curve (AUC). Sex-specific patterns in tumor subsites and differences in clinical staging according to age were demonstrated in the patients with OSCC. The proportion of well-differentiated cases was significantly higher in most tumor subsites, except in the buccal mucosa (more moderately differentiated cases) and floor of the mouth (well and moderately differentiated cases being equal). LVI was significantly associated with nodal metastasis but not distant metastasis. Multivariate analysis demonstrated that age ≤45 years [odds ratio (OR), 2.26] and LVI (OR, 8.42) predicted patients having advanced-stage OSCC among general populations (AUC, 0.773); however, LVI (OR, 8.28) was the sole predictor of advanced stage amongst young patients (AUC, 0.737). Margin invasion was predicted solely by tumor subsite, including mouth not otherwise specified (OR, 3.04) and palate (OR, 6.13), in the general population (AUC, 0.711). Furthermore, margin invasion was predicted by the palate subsite (OR, 38.77) and LVI (OR, 11.61) in young patients (AUC, 0.762). Investigating young patients thoroughly when finding SCC in the mouth and palate, and assessing LVI, especially among young patients, is critical to prevent advanced staging and margin invasion.

Survival rate and prognostic factors of oral squamous cell carcinoma in Indonesia: A single-center retrospective study

Background

Oral squamous cell carcinoma (OSCC) is the sixth most common malignancy in Asia. Most patients in Cipto Mangunkusumo Hospital have been diagnosed with an advanced stage. There had not been any survival study for OSCC in Indonesia. This study aimed to investigate the survival rate and prognostic factors of OSCC in Cipto Mangunkusumo Hospital.

Methods

A retrospective cohort study was conducted on OSCC patients diagnosed and treated in Cipto Mangunkusumo Hospital from 2014 to 2018. Data regarding age, gender, site of the primary lesion, clinical stage of the disease, tumor differentiation, invasion, and surgical margins were collected. The main outcomes measured were overall survival (OS) and disease-specific survival (DSS). The predictors of survival were then determined.

Result

169 patients were included. The majority of patients were male (51.5%) and above 50 years old (55.6%). The most prevalent tumor site was the tongue (72.8%) followed by buccal mucosa (13%). The majority (82.2%) of patients had advanced (clinical stage IV) disease at diagnosis. A smaller majority of patients had a well-differentiated tumor (60.4%) and a low-grade tumor (53.8%). The worst one-year and two-year overall survival rates were found in the stage IV group (53.5% and 37.5%, respectively). The disease-specific survival rate was 66.9%.

Conclusion

The one-year and two-year overall survival rates of OSCC in Cipto Mangunkusumo Hospital were 58.6% and 43.1%. Moreover, clinical stage, tumor size, and lymph node involvement were the most significant prognostic factors for OSCC.

Lack of association between dental implants and oral squamous cell carcinoma

Design A systematic review of the literature to identify and evaluate the epidemiologic profile, and screen for possible risk factors and spectrum of clinical characteristics of oral squamous cell carcinoma (OSCC) surrounding dental implants, was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement guidelines.Data sources A search of two databases, Medline and CENTRAL, was undertaken, limited to articles published in English from the oldest records until 10 July 2018. Google Scholar was the grey literature searched. The references list in the included articles was assessed for further inclusion suitability.Study selection Participants included patients diagnosed with OSCC surrounding dental implants. The comparator or control was patients diagnosed with OSCC without dental implants. The outcome was epidemiology and carcinogenesis. The considered study designs were case reports, case series and retrospective studies. Article selection was performed by screening titles and abstracts individually by two blind review authors using the Rayyan platform based on the inclusion criteria. Then, the full text of the selected articles was assessed to identify the eligible articles, and the reasons for exclusion were reported. When a consensus was not achieved between the review authors, a third review author, who acted as a tiebreaker, was consulted.Data extraction Two independent review authors extracted the data using a specific extraction form in Microsoft Office Excel (Microsoft Corporation, Redmond, WA, USA). The extraction form consisted of authors, publication year, country, study design, number of cases, age, sex, risk factors, region of interest, the clinical aspect of the lesion, radiographic findings, the period between implant placement and tumour diagnosis, treatment, and follow-up. The time reported in the studies was converted to months for comparison. A third review author validated the accuracy of the information collected.Synthesis Two independent review authors assessed the risk of bias by applying the Joanna Briggs Institute (JBI) Critical Appraisal Checklist (CAP) for Case Reports and the JBI CAP for Prevalence Studies (for example, retrospective studies). Disagreements were resolved by consulting a third co-author. The Grading of Recommendation, Assessment, Development and Evaluation (GRADE) tool evaluated the certainty of the evidence of the main outcomes. A PRISMA flow diagram was presented, and a table summary of descriptive characteristics of the 33 included studies. Among the figures available, bar graphs represented the 'clinical features' according to the previous history of oral potentially malignant disorders and regarding the malignancy of oral potentially malignant disorders. In addition, a stacked line with markers represented the sex of the number of cases, displaying the time until diagnosis after implant placement and the time to disease progression.Data analysis A qualitative synthesis was provided. No quantitative data synthesis nor inter-rater agreement assessment was conducted.Results Thirty-one case reports and two retrospective studies, published between 1983 and 2020, met the eligibility criteria. The total sample consisted of 63 patients (male = 44.5%) with an average of 66.7 years (range = 42 to 90 years). Oral potentially malignant disorders were found in 29 patients (46%), of which 65.5% were female patients. The most common lesions were oral lichen planus and leukoplakia in female patients (52.6% and 31.5%) and male patients (20% and 60%). In 25 patients (39.6%), there was information missing about the presence of potentially malignant oral disorders, and oral hygiene status was reported in only 17.4% of the cases. Fifty-six patients (88.8%) of OSCC with dental implants were located in the mandible, and the most common clinical presentations of OSCC with implants were exophytic mass (46%) and ulceration (36.5%). Peri-implant bone loss assessment was performed in 51 patients (80.9%), of which 44 (86.2%) had peri-implant bone loss. Thus, most of these lesions were originally treated as peri-implantitis.Conclusions Most patients with OSCC next to their dental implants were female patients lacking known risk factors, and the common location was the mandible with an exophytic mass or ulceration presentation. A major concern is that the clinical and radiographic features of OSCC could be misdiagnosed as peri-implantitis. Thus, OSCC should be considered in persistent lesions surrounding dental implants. Several of the included reports were missing previous medical history and follow-up information. Hence, better case series and studies are required to support or reject the notion of an association between dental implants and OSCC.

Significance of Pattern of Invasion in Tongue Squamous Cell Carcinoma—A Retrospective Study from a Regional Cancer Center of North-East India

Introduction Many multiparametric models and scoring systems had been proposed in oral tongue squamous cell carcinoma (OTSCC) to predict the survival and recurrence, out of which pattern of invasion (POI) is gaining focus recently.

Objective We conducted a retrospective study with the aim to see the prognostic significance of the POI and other parameters such as depth of invasion, perineural invasion (PNI), and lymph node status in OTSCC.

Materials and Methods The slides of already diagnosed OTSCC cases were prepared from January 2015 to December 2017 records and studied by two pathologists for different patterns using Brandwein-Gensler scoring system. The different clinicopathologic parameters were compared with different POI. Statistical analysis was performed to present cumulative survival outcomes and for comparison.

Results Most of our patients were > 40 years of age with male preponderance. Tumor differentiation pattern was assessed using Broders' system of grading that showed 85% of tumors were well, 12.5% tumors were moderately differentiated, and 2.5% tumors were poorly differentiated. The worst POI was predominantly pattern III (50%) followed by pattern II (32.5%) and pattern IV (13.8%). Most patients were in stage II (33.8%) followed by stage III (32.5%), stage IV (26.3%), and stage I (7.5%). There was an inverse relationship between POI with tumor stage and recurrence. A strong statistically significant association was found between POI with perineural infiltration and lymph node metastasis.

Conclusion We concluded from our study that worst POI is significantly associated with number of lymph nodes metastasis and perineural infiltration and hence can be used as an independent prognostic factor.

Diagnostic accuracy of conventional oral examination for detecting oral cavity cancer and potentially malignant disorders in patients with clinically evident oral lesions: Systematic review and meta-analysis

This systematic review evaluates the diagnostic accuracy of conventional oral examination (COE) versus incisional or excisional biopsy for the diagnosis of malignant and/or dysplastic lesions in patients with clinically evident lesions. Searches were conducted across five electronic databases from inception to January 2020. Meta‐analyses were undertaken, where appropriate. Among 18 included studies, 14 studies were included in the meta‐analysis, giving summary estimates for COE of 71% sensitivity and 85% specificity for the diagnosis of dysplastic and/or malignant lesions. The pooled diagnostic accuracy of identifying malignant‐only lesions was reported in seven studies, giving a pooled estimate of 88% sensitivity and 81% specificity. Diagnostic accuracy of different types of dental/medical professionals in identifying dysplastic or malignant lesions gave varying estimates of sensitivity and specificity across three studies. Further research is needed to improve the diagnostic accuracy of COE for early detection of dysplastic and malignant oral lesions.

Cancer-Associated Stromal Cells Promote the Contribution of MMP2-Positive Bone Marrow-Derived Cells to Oral Squamous Cell Carcinoma Invasion

Simple Summary

Based on its invasiveness, oral squamous cell carcinoma (OSCC) shows two different subtypes: less-invasive verrucous squamous carcinoma (VSCC) or highly invasive squamous cell carcinoma (SCC). The stromal component influences OSCC progression and invasion. On the other hand, bone marrow-derived cells (BMDCs) are recruited into tumors and involved in tumor development. We hypothesized that stromal factors might also affect the relation of BMDCs and tumor invasion. We established the OSCC models transplanted with stromal cells from VSCC and SCC, and we compared the potential stromal factors of VSCC and SCC for the involvement of BMDCs in tumor invasion. Our study showed that stromal factors IL6 and IL1B might promote the contribution of MMP-2 positive BMDCs to OSCC invasion.

Abstract

Tumor stromal components contribute to tumor development and invasion. However, the role of stromal cells in the contribution of bone marrow-derived cells (BMDCs) in oral squamous cell carcinoma (OSCC) invasion is unclear. In the present study, we created two different invasive OSCC patient-derived stroma xenografts (PDSXs) and analyzed and compared the effects of stromal cells on the relation of BMDCs and tumor invasion. We isolated stromal cells from two OSCC patients: less invasive verrucous OSCC (VSCC) and highly invasive conventional OSCC (SCC) and co-xenografted with the OSCC cell line (HSC-2) on green fluorescent protein (GFP)-positive bone marrow (BM) cells transplanted mice. We traced the GFP-positive BM cells by immunohistochemistry (IHC) and detected matrix metalloproteinase 2 (MMP2) expression on BM cells by double fluorescent IHC. The results indicated that the SCC-PDSX promotes MMP2-positive BMDCs recruitment to the invasive front line of the tumor. Furthermore, microarray analysis revealed that the expressions of interleukin 6; IL-6 mRNA and interleukin 1 beta; IL1B mRNA were higher in SCC stromal cells than in VSCC stromal cells. Thus, our study first reports that IL-6 and IL1B might be the potential stromal factors promoting the contribution of MMP2-positive BMDCs to OSCC invasion.

LncRNA LINC01303 Promotes the Progression of Oral Squamous Cell Carcinomas via the miR-429/ZEB1/EMT Axis

Objectives

The aim of this research was to uncover the biological role and mechanisms of LINC01303 in oral squamous cell carcinoma (OSCC).

Materials and Methods

Real-time quantitative PCR (qRT-PCR) was used to determine LINC01303 expression in OSCC tissues. Subcellular distribution of LINC01303 was examined by nuclear/cytoplasmic RNA fractionation and FISH experiments. The role of LINC01303 in the growth of TSCCA and SCC-25 was examined by CCK-8 assay, colony formation, transwell invasion assay in vitro, and xenograft tumor experiment in vivo. Dual-luciferase reporter assay was used to verify the interaction between LINC01303 and miR-429. RNA pull‐down assay was used to discover miR-429‐interacted protein, which was further examined by qRT-PCR, western blot, and rescue experiments.

Results

LINC01303 expression was higher in OSCC tissues compared with adjacent nontumor tissues. LINC01303 was found to be localized in the cytoplasm of OSCC cells. Knockdown of LINC01303 inhibited OSCC cell proliferation and invasion, whereas increasing the expression of LINC01303 showed the opposite effects. Furthermore, LINC01303 served as a miR-429 “sponge” and positively regulated ZEB1 expression. Moreover, LINC01303 promoted OSCC through miR-429/ZEB1 axis both in vivo and in vitro.

Conclusions

LINC01303 plays an oncogenic role in OSCC and is a promising biomarker for OSCC patients.

Isoprenylcysteine carboxyl methyltransferase promotes the progression of tongue squamous cell carcinoma via the K-Ras and RhoA signaling pathways

OBJECTIVE

This research investigated the biological role of isoprenylcysteine carboxyl methyltransferase (ICMT) in tongue squamous cell carcinoma (TSCC) progression meanwhile to explore the conceivable mechanism.

METHODS

The mRNA and protein expression were measured using real-time PCR and Western blot. Cell proliferation, apoptosis, cycle distribution, migration and invasion were evaluated by CCK-8 assay, flow cytometry, wound-healing assay and transwell assay. The anti-tumor activity of ICMT silencing was observed in nude mice.

RESULTS

Our results indicated that silencing of ICMT-mediated methylation effectively inhibited TSCC cells proliferation in vitro and reduced tumor growth in vivo. Moreover, ICMT knockdown also induced cell apoptosis and cell cycle arrest of both CAL-27 and SCC-4 cells. In addition, CAL-27 and SCC-4 cells migration and invasion were weakened by ICMT siRNA. Mechanistically, ICMT deficiency significantly decreased the K-Ras and RhoA membrane targeting localization, leading to the suppression of K-Ras- and RhoA-mediated downstream signaling in CAL-27 and SCC-4 cells.

CONCLUSIONS

Altogether, our findings identified a crucial role played by ICMT in the progression of TSCC and the potential mechanisms by which exerted its effects, indicating that targeting ICMT may represent a promising therapeutic strategy for TSCC.

Methanol extract of Sedum oryzifolium and its constituent, trehalose, impede the invasiveness of oral squamous cell carcinoma cell lines via downregulation of Slug

BACKGROUND

Sedum species are reported to possess diverse pharmacological activities in various solid tumors. However, the anticancer functions of Sedum orizyfolium and its constituents have never been determined in human cancers.

PURPOSE

The present study focused on addressing the inhibition efficacy of the methanol extract of S. orizyfolium (MESO) and its constituents and the molecular mechanism underlying invasion and epithelial-to-mesenchymal transition (EMT) in oral squamous cell carcinoma (OSCC) cell lines.

STUDY DESIGN/METHODS

After MESO treatment, a wound-healing assay, an invasion assay, and immunocytochemistry were performed in OSCC cell lines, coupled with in silico analysis and immunohistochemistry in OSCC patient samples, to investigate the role of the EMT transcription factor Slug. Trehalose, an active component of MESO, was identified through gas chromatography-mass spectrometry.

RESULTS

Among the methanol extracts of 18 various wild plants from South Korea, MESO exhibited the highest anticancer functionality in OSCC cells by downregulating Slug expression. In silico analysis and immunohistochemistry indicated that elevated Slug levels are remarkably associated with tumor progression and invasion in patients with OSCC, suggesting that changes in Slug expression alter EMT progression and invasion in OSCC. Notably, treatment with trehalose, a sugar component of MESO, inhibited invasiveness and Slug expression in OSCC cells.

CONCLUSION

Cumulatively, this study highlighted the beneficial role of MESO and trehalose in the inhibition of invasiveness of OSCC cells via suppression of Slug expression and suggested a new design for potential chemotherapeutic drugs against OSCC.

The Tissue Architecture of Oral Squamous Cell Carcinoma Visualized by Staining Patterns of Wheat Germ Agglutinin and Structural Proteins Using Confocal Microscopy

OBJECTIVES

Tissue architecture and cell morphology suffer profound alterations during oral cancer and are important markers for its progression and outcome. For precise visualization of tissue architecture in oral cancer, we used confocal microscopy to examine the staining pattern of wheat germ agglutinin, a lectin that binds membrane glycoproteins, and the staining patterns of structural proteins.

MATERIALS AND METHODS

Paraffin sections of oral squamous cell carcinoma were stained with fluorescently labeled wheat germ agglutinin and with antibodies against structural proteins, which were revealed by immunohistochemistry with tyramide signal amplification.

RESULTS

Membrane localization of wheat germ agglutinin was markedly decreased in the basal layers and in regions of tumor invasion, accompanied by cytoplasmic redistribution of E-cadherin, β-actin and syndecan-1. Wheat germ agglutinin staining clearly identified tumor clusters within the surrounding stroma, and tumor cells with elongated morphology.

CONCLUSIONS

Our results suggest that the wheat germ agglutinin staining pattern is indicative of the degree of cell cohesion in oral squamous cell carcinoma, which decreases in basal layers and invasive tumor clusters with more migratory morphologies. Wheat germ agglutinin staining in combination with confocal microscopy could constitute, therefore, a valuable tool for the study of tissue architecture in oral cancer.

Polydatin, a Glycoside of Resveratrol, Induces Apoptosis and Inhibits Metastasis Oral Squamous Cell Carcinoma Cells In Vitro

Although various methods, such as surgery and chemotherapy, are applied to the treatment of OSCC, there are problems, such as functional and aesthetic limitations of the mouth and face, drug side effects, and lymph node metastasis. Many researchers are making efforts to develop new therapeutic agents from plant-derived substances to overcome the side effects that occur in oral cancer treatment. Polydatin is known as a natural precursor of resveratrol, and research on its efficacy is being actively conducted recently. Therefore, we investigated whether polydatin can induce apoptosis and whether it affects cell migration and invasion through the regulation of EMT-related factors in OSCC. Polydatin decreased the survival and proliferation rates of CAL27 and Ca9-22 cells, and induced the release of cytochrome c, a factor related to apoptosis, and fragmentation of procaspase-3 and PARP. Another form of cell death, autophagy, was observed in polydatin-treated cells. In addition, polydatin inhibits cell migration and invasion, and it has been shown to occur through increased expression of E-cadherin, an EMT related factor, and decreased expression of N-cadherin and Slug and Snail proteins and genes. These findings suggest that polydatin is a potential oral cancer treatment.

Survival-Based Biomarker Module Identification Associated with Oral Squamous Cell Carcinoma (OSCC)

Simple Summary

In this study, four OSCC-specific hub genes were identified using high-throughput RNA-Seq data from TCGA cohort. The significant genes within tumor and normal samples were used for weighted PPI network construction based on survival of patients along with their expression profiles. The analysis revealed the most significant module in the training and test datasets. The genes from this module were used for pathway enrichment analysis followed by hub gene selection. These novel biomarkers might have clinical utility for diagnosis and prognosis prediction in OSCC, providing diagnosis at a very early stage. Moreover, a combination of all these biomarkers might distinguish the OSCC patients with low risk and high risk for cancer progression and recurrence, which will provide useful guidance for personalized and precision therapy. However, the results in the present study were obtained by integrative theoretical analysis, and the findings remain to be confirmed by further experimental validations.

Abstract

Head and neck squamous cell carcinoma (HNSC) is one of the most common malignant tumors worldwide with a high rate of morbidity and mortality, with 90% of predilections occurring for oral squamous cell carcinoma (OSCC). Cancers of the mouth account for 40% of head and neck cancers, including squamous cell carcinomas of the tongue, floor of the mouth, buccal mucosa, lips, hard and soft palate, and gingival. OSCC is the most devastating and commonly occurring oral malignancy, with a mortality rate of 500,000 deaths per year. This has imposed a strong necessity to discover driver genes responsible for its progression and malignancy. In the present study we filtered oral squamous cell carcinoma tissue samples from TCGA-HNSC cohort, which we followed by constructing a weighted PPI network based on the survival of patients and the expression profiles of samples collected from them. We found a total of 46 modules, with 18 modules having more than five edges. The KM and ME analyses revealed a single module (with 12 genes) as significant in the training and test datasets. The genes from this significant module were subjected to pathway enrichment analysis for identification of significant pathways and involved genes. Finally, the overlapping genes between gene sets ranked on the basis of weighted PPI module centralities (i.e., degree and eigenvector), significant pathway genes, and DEGs from a microarray OSCC dataset were considered as OSCC-specific hub genes. These hub genes were clinically validated using the IHC images available from the Human Protein Atlas (HPA) database.

Using the Exploratory Sequential Mixed Methods Design to Investigate Dental Patients' Perceptions and Needs Concerning Oral Cancer Information, Examination, Prevention and Behavior

Objectives: The objective of this study was to investigate dental patients’ behavior, thoughts, opinions and needs for oral cancer information, and dentists’ behavior regarding prevention and examination of oral cancer. Materials and Methods: This study utilized an exploratory sequential mixed methods design. Semi-structured interviews with open-ended questions were conducted for forty dental patients of both sexes. Based on the qualitative analysis, a structured questionnaire was developed and distributed among the participants. Data were analyzed for 315 participants to quantify their thoughts, needs, behavior and behavior expected from dentists regarding oral cancer. Frequency, percentages and cumulative percentages were calculated. Results: This study reveals that patients’ oral cancer knowledge levels were adequate, but most reported that their dentist had never examined them for oral cancer. Additionally, the participants had never performed self-examinations for oral cancer, nor were they aware of the possibility of doing so. Participants showed a preference for being examined and educated by their dentist about oral cancer and believed it would help early detection. Conclusions: The study participants are aware of oral cancer and its risk factors. The practice of oral cancer examinations and patient education of its risk factors by dental practitioners is limited. Patients feel a need for more attention to be paid to oral cancer examinations, preventive measures and targeted information on oral cancer risk factors.

Exploring the Cytotoxic Effects of the Extracts and Bioactive Triterpenoids from Dillenia indica against Oral Squamous Cell Carcinoma: A Scientific Interpretation and Validation of Indigenous Knowledge

Triterpenoids are ubiquitously distributed secondary metabolites, primarily scrutinized as a source of medication and preventive measures for various chronic diseases. The ease of isolation and excellent pharmacological properties of triterpenoids are notable reasons behind the exponential rise of extensive research on the bioactive triterpenoids over the past few decades. Herein, we attempted to explore the anticancer potential of the fruit extract of the ethnomedicinal plant Dillenia indica against oral squamous cell carcinoma (OSCC) and have exclusively attributed the efficacy of the extracts to the presence of two triterpenoids, namely, betulinic acid (BA) and koetjapic acid (KA). Preliminary in vitro screening of both BA and KA unveiled that the entities could impart cytotoxicity and induce apoptosis in OSCC cell lines, which were further well-supported by virtual screening based on ligand binding affinity and molecular dynamic simulations. Additionally, the aforementioned metabolites could significantly modulate the critical players such as Akt/mTOR, NF-κB, and JAK/STAT3 signaling pathways involved in the regulation of important hallmarks of cancer like cell survival, proliferation, invasion, angiogenesis, and metastasis. The present findings provide insight and immense scientific support and integrity to a piece of indigenous knowledge. However, in vivo validation is a requisite for moving to clinical trials and developing it as a commercial drug.

Oral squamous cell carcinoma around dental implants: a systematic review

OBJECTIVE

This systematic review aimed to evaluate the epidemiologic profile, screen for possible risk factors, and evaluate the spectrum of clinical characteristics of oral squamous cell carcinoma (OSCC) around dental implants (DIs).

METHODS

The systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta- Analyses statement.

RESULTS

Thirty-three articles met the eligibility criteria. In total, the sample consisted of 63 patients, and women comprised the majority (55.5%). The mean age of patients was 66.7 years. Oral potentially malignant disorders were reported in 46% of patients, of which 65.5% occurred in women. The most common lesion found in women was oral lichen planus (52.6%). In 88.8% of patients OSCC around DIs occurred in the mandible, and the most common clinical appearance of the lesions was an exophytic mass (46%). Most of these lesions were initially treated as peri-implantitis.

CONCLUSIONS

Most patients with OSCC around DIs were women without known risk factors. It is important to emphasize that these lesions may present clinical and radiographic features that could resemble peri-implantitis, which can lead to delay in the diagnosis and subsequent treatment.

Clinicopathological Features Associated with Fluorescence Alteration: Analysis of 108 Oral Malignant and Potentially Malignant Lesions

Background: Several noninvasive diagnostic tools have been developed to aid the early detection of oral cancer and for evaluation before definitive biopsy. Among these, devices evaluating a tissues autofluorescence (AF) are emerging. In particular, the most well known of these is the VELscope^® system (LED Medical Diagnostics, Inc., Barnaby, Canada), which emits a light of 400-460 nm. This study has been developed to describe the most relevant clinicopathological features associated with AF alterations in a set of patients with oral squamous cell carcinoma and potentially malignant disorders (PMDs). Materials and methods: Overall, 108 lesions from 60 patients with clinical diagnoses of potentially malignant oral disorders and carcinomas were included in the study. For each case, the following variables were recorded and compared with the AF pattern: (1) clinical appearance (white, red, and white/red); (2) histological diagnosis (no dysplasia, mild/moderate dysplasia, severe dysplasia/in situ carcinoma, invasive carcinoma, and verrucous carcinoma); and (3) clinicopathological diagnosis. Binomial logistic regression was performed to investigate whether clinical appearance and/or histological diagnosis were significant in determining the degree of AF. Results: Among the white lesions, 66% resulted in hyper-fluorescence, whereas the red lesions appeared hypo-fluorescent in 95.2% of cases. The AF was altered (both hypo-fluorescent and hyper-fluorescent) in 36% of lesions without dysplasia; in 75.9% of lesions with mild or moderate dysplasia and in the totality of the in situ, invasive, and verrucous carcinomas (p < 0.0001). With regard to the binomial logistic regression, variables were separately considered and both were extremely significant in determining the degree of AF. Conclusions: Promising evidence for the use of AF as an adjunctive tool to conventional oral examinations (COEs) has been demonstrated. However, although the sensitivity of AF examination associated with COE is very high, both the literature and this study agree to indicate a low specificity.

Identification of a Transcriptional Prognostic Signature From Five Metabolic Pathways in Oral Squamous Cell Carcinoma

Dysregulated metabolic pathways have been appreciated to be intimately associated with tumorigenesis and patient prognosis. Here, we sought to develop a novel prognostic signature based on metabolic pathways in patients with primary oral squamous cell carcinoma (OSCC). The original RNA-seq data of OSCC from The Cancer Genome Atlas (TCGA) project and Gene Expression Omnibus (GEO) database were transformed into a metabolic pathway enrichment score matrix by single-sample gene set enrichment analysis (ssGSEA). A novel prognostic signature based on metabolic pathways was constructed by LASSO and stepwise Cox regression analysis in the training cohort and validated in both testing and validation cohorts. The optimal cut-off value was obtained using the Youden index by receiver operating characteristic (ROC) curve. The overall survival curves were plotted by the Kaplan-Meier method. A time-dependent ROC curve analysis with 1, 3, 5 years as the defining point was performed to evaluate the predictive value of this prognostic signature. A 5-metabolic pathways prognostic signature (5MPS) for OSCC was constructed which stratified patients into subgroups with favorable or inferior survival. It served as an independent prognostic factor for patient survival and had a satisfactory predictive performance for OSCC. Our results developed a novel prognostic signature based on dysregulated metabolic pathways in OSCC and provided support for aberrant metabolism underlying OSCC tumorigenesis.

Epidemiological profile and clinical implications of oral squamous cell carcinoma adjacent to dental implants

OBJECTIVES

Describe the epidemiological profile of patients with oral squamous cell carcinoma (OSCC) around dental implants (DI), investigate the spectrum of clinical and pathological characteristics, and discuss the implications of diagnosis delay of these lesions.

METHODS

Retrospective analysis of patients treated of OSCC adjacent to DI at A.C. Camargo Cancer Center between 2009 and 2020.

RESULTS

Thirty one patients were identified, being women the majority (58.1%). The mean age of the patients was 68.8 years. Never smoker corresponds to 46.9% and never alcohol consumer to 54.9% of the sample. OPMD was reported in 45.2% of patients, affecting mainly women (78.5%). Leukoplakia (63.7%) followed by oral lichen planus (36.3%) was the most common OPMD found in women. OSCC adjacent to DI occurred in the inferior gingiva/alveolar mucosa in 48.3% of cases, and ulceration was the most common clinical appearance (87%). Peri-implantitis (PI) was initial clinical diagnosis in 16.1% of cases.

CONCLUSIONS

Oral squamous cell carcinoma adjacent to DI was more common in women over 70 years old, non-smokers and non-drinker, and the majority had oral leukoplakia before the diagnosis of OSCC. OSCC may present clinical and radiographic features that resemble PI which can delay the diagnosis and impair the prognosis.

Epidemiology and pathology of oral squamous cell carcinoma in a multi-ethnic population: Retrospective study of 154 cases over 7 years in Qatar

Background

Oral cancer (OC) is a neoplastic process of the oral cavity that has high mortality and significant effects on patients' aesthetics. The majority of OC is oral squamous cell carcinoma (OSCC) and resection remains the most frequent treatment. Recurrence is the main cause of tumor-related mortality.

Material and methods

A retrospective review of patients' charts at Hamad Medical Corporation examined 154 adults who were diagnosed as OSCC and referred to the national head and neck cancer multi-disciplinary team meetings between 2012 and 2018. The data extracted was demographic, pathologic and clinical. All patients with oral cavity tumors other than squamous cell carcinoma were excluded.

Results

Males comprised the majority of the sample, mean age was 46.93 years. Tongue was the most common location. The majority of the patients were diagnosed at early stages, and a small subset of patients had histologically-proven local recurrence.

Conclusion

The young male predominance of OSCC patients in Qatar is unprecedented worldwide. Most patients were non-Qataris, mainly from South Asia. Loss of follow-up was a challenge in assessing the long-term outcomes of OSCC. Our findings suggest the need for a more vigilant surveillance approach to oral lesions particularly in male South-Asian patients, as well as improving the follow-up strategies.

Impact of Histological and Molecular Parameters on Prognosis of Oral Squamous Cell Carcinoma: Analysis of 290 Cases

Background

Nodal metastasis is a critical factor in predicting the prognosis of oral squamous cell carcinoma (OSCC). When patients present with a clinically positive neck, the treatment of choice is radical neck dissection. However, management of a clinically negative neck is still a subject of significant controversy.

Aim

This study was carried out in order to propose a model to predict regional lymph node metastasis of OSCC using histological parameters such as tumour stage, tumour size, pattern of invasion (POI), differentiation of tumour, and host immune response, together with the expression levels of six biomarkers (periostin, HIF-1α, MMP-9, β-catenin, VEGF-C, and EGFR), and, furthermore, to compare the impact of all these parameters on recurrence and 3 yr and 5 yr survival rates. Materials and Method. Histological materials collected from the archives were used to evaluate histological parameters and immunohistochemical profiles. Standard methods were used for immunohistochemistry and for evaluation of results. Data related to recurrence and survival (3 and 5 years) was also recorded. Clinical data was collected from patients' records.

Results

Male to female ratio was 3 : 1. The commonest site of OSCC was the buccal mucosa, and majority of them were T3 or T4 tumours presented at stage 4. 62.5% of the tumours were well differentiated. Three-year and 5-year survival rates were significantly associated with lymph node metastasis and recurrence. POI was significantly correlated with tumour size, stage, 3-year survival, EGFR, HIF-1α, periostin, and MMP-9 (p < 0.05). Expression of EGFR showed a direct association with metastasis (p < 0.05).

Conclusion

POI, level of differentiation, and expression of EGFR are independent prognostic markers for lymph node metastasis. Therefore, these parameters may help in treatment planning of a clinically negative neck.

Dental Calculus as a Potential Biosource for Human Papillomavirus Detection in Oral Squamous Cell Carcinoma

OBJECTIVE

The infection of human papillomaviruses (HPVs) plays a role in the development of oral squamous cell carcinoma (OSCC). A poor oral hygiene and dental calculus may cause the infection to persist. Therefore, this study aimed to assess whether this dental calculus could serve as a potential biosource in early detection of HPVs in patients with OSCC.

METHODS

DNA was isolated from the dental calculus of people diagnosed with OSCC, and MY09/11 primer set was used to detect the presence of HPV. The positive samples were further sequenced and aligned using megablast NCBI BLAST tool to identify the HPV genotype.

RESULTS

Electrophoresis examination showed that 4 of 14 samples collected (29%) had a clear single band, of which three had 97% to 99% similarity to a high-risk genotype HPV-58. Meanwhile, the other sample had 99% similarity to an unclassified papillomaviridae.

CONCLUSION

Dental calculus is a promising source of HPV in oral cavity and could be used as a biomarker for early detection.

Obg-like ATPase 1 inhibited oral carcinoma cell metastasis through TGFβ/SMAD2 axis in vitro

BACKGROUND

The human Obg-like ATPase 1 (OLA1) protein has been reported to play an important role in cancer cell proliferation. The molecular mechanism underlying OLA1 regulated oral metastasis is still unknown. We investigated in this study the regulatory role of OLA1 playing in oral squamous cell metastasis.

RESULTS

A series of in vitro assays were performed in the cells with RNAi-mediated knockdown or overexpression to expound the regulatory function of OLA1 in oral cancer. We found that the endogenous level of OLA1 in a highly metastatic oral squamous cell line was significantly lower than that in low metastatic oral cells as well as in normal oral cells. Escalated expression of OLA1 resulted in a reduced ability of metastasis in highly metastatic cells, and enhanced its sensitivity to the paclitaxel treatment. Further analysis of the EMT markers showed that Snail, Slug, N-cadherin were up-expressed significantly. Meanwhile, E-cadherin was significantly down-regulated in the oral cancer cells with OLA1-knocked down, suggesting that OLA1 inactivated EMT process. Furthermore, we found that OLA1 suppressed oral squamous cell metastasis by suppressing the activity of a TGFβ/SMAD2/EMT pathway.

CONCLUSION

Our data suggests that OLA1 may be developed as a potential target for the treatment of oral cancer metastasis.

Biomarkers of progression to oral cancer in patients with dysplasia: A systematic review

Identifying oral dysplastic lesions with a high risk of malignant transformation may create opportunities for early therapeutic interventions. Several tissue biomarkers have been suggested to date as prognostic indicators of the progression of dysplastic lesions to oral cancer. We herein present a systematic review (PROSPERO CRD42018086476), with the aim of identifying, evaluating and summarizing evidence on prognostic biomarkers of progression to oral cancer in patients with dysplasia. A search through MEDLINE/PubMed and Scopus databases was performed. The review only included primary articles that reported risk values associated with malignancy after a multivariate analysis. The quality of the findings was analyzed using the Reporting Recommendations for Tumor Marker Prognostic Studies, and research trends were established using SciCurve Open. A total of 4 potential biomarkers were identified: Degree of dysplasia, and the proteins retinal dehydrogenase 1, prominin-1 and podoplanin. All 3 protein biomarkers have been recognized as cancer stem cell markers. The studies were of acceptable quality, although none included sample size determinations. Due to the lack of validation and follow-up studies, these biomarkers are considered to be in a discovery phase and require validation by prospective clinical trials. The present analysis indicated that there are currently insufficient data to include these biomarkers in the clinical decision-making process.

Differentially expressed full-length, fusion and novel isoforms transcripts-based signature of well-differentiated keratinized oral squamous cell carcinoma

Highly keratinized oral squamous cell carcinoma (OSCC) exhibits an improved response to treatment and prognosis compared with weakly keratinized OSCC. Therefore, we aimed to develop gene transcript signature and to identify novel full-length isoforms, fusion transcript and non-coding RNA to differentiate well-differentiated (WD) with Moderately Differentiated (MD)/Poorly Differentiated (PD)/WD-lymphadenopathy OSCC through, HTA, Isoform sequencing, and NanoString. Additionally, specific copy number gain and loss were also identify in WD keratinized OSCC through Oncoscan array and validated through Real-time PCR in histopathologically characterized FFPE-WD keratinized OSCC. Three-hundred-thirty-eight (338) differentially expressed full-length (FL) transcript isoforms (317 upregulated and 21 down-regulated in OSCC) were identified through Isoform Sequencing using the PacBio platform. Thirty-four (34) highly upregulated differentially expressed transcripts from IsoSeq data were also correlated with HTA2.0 and validated in 42 OSCC samples. We were able to identify 18 differentially expressed transcripts, 12 fusion transcripts, and two long noncoding RNAs. These transcripts were involved in increased cell proliferation, dysregulated metabolic reprogramming, oxidative stress, and immune system markers with enhanced immune rearrangements, suggesting a cancerous nature. However, an increase in proteasomal activity and hemidesmosome proteins suggested an improved prognosis and tumor cell stability in keratinized OSCC and helped to characterize WD with MD/PD/WD with lymphadenopathy OSCC. Additionally, novel isoforms of IL37, NAA10, UCHL3, SPAG7, and RAB24 were identified while in silico functionally validated SPAG7 represented the premalignant phenotype of keratinized (K4) OSCC. Most importantly we found copy number gain and overexpression of EGFR suggest that TKIs may also be used as therapeutics in WD-OSCCs.

Assessing the potential role of neutrophil elastase as a prognostic indicator in oral squamous cell carcinoma

Past decade has seen the advent of several prognosticators for oral squamous cell carcinoma (OSCC). Although TNM staging is still considered as the prognostic gold standard, it is not possible to obtain all the necessary information for a pathological TNM staging until excisional biopsy. Thus, it is necessary to identify features from the initial biopsy, which could aid in early prognostication.

Aim

To compare neutrophil elastase immuno-expression in oral squamous cell carcinoma patients with and without lymph node metastasis.

Materials and Methods

Archival specimens of 50 oral squamous cell carcinoma consisting of 25 cases with and 25 cases without lymph node metastasis were immuno-stained for neutrophil elastase.

Results

Statistically, a significant difference was noted in the neutrophil elastase staining between the 2 groups. 18 of the 25-oral squamous cell carcinoma cases with lymph node metastasis were positive and only 5 of the 25-oral squamous cell carcinoma cases without nodal involvement were positive.

Conclusion

Presence of neutrophil elastase in the lesional tissue is strongly associated with a lymph node involvement, and thus could serve as a prognostic factor for oral squamous cell carcinoma.

Identification of cancer hallmark-associated gene and lncRNA cooperative regulation pairs and dictate lncRNA roles in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common malignant tumour in the oral and maxillofacial region. Numerous cancers share ten common traits ("hallmarks") that govern the transformation of normal cells into cancer cells. Long non-coding RNAs (lncRNAs) are important factors that contribute to tumorigenesis. However, very little is known about the cooperative relationships between lncRNAs and cancer hallmark-associated genes in OSCC. Through integrative analysis of cancer hallmarks, somatic mutations, copy number variants (CNVs) and expression, some OSCC-specific cancer hallmark-associated genes and lncRNAs are identified. A computational framework to identify gene and lncRNA cooperative regulation pairs (GLCRPs) associated with different cancer hallmarks is developed based on the co-expression and co-occurrence of mutations. The distinct and common features of ten cancer hallmarks based on GLCRPs are characterized in OSCC. Cancer hallmark insensitivity to antigrowth signals and self-sufficiency in growth signals are shared by most GLCRPs in OSCC. Some key GLCRPs participate in many cancer hallmarks in OSCC. Cancer hallmark-associated GLCRP networks have complex patterns and specific functions in OSCC. Specially, some key GLCRPs are associated with the prognosis of OSCC patients. In summary, we generate a comprehensive landscape of cancer hallmark-associated GLCRPs that can act as a starting point for future functional explorations, the identification of biomarkers and lncRNA-based targeted therapy in OSCC.

Erianin Induces Apoptosis and Autophagy in Oral Squamous Cell Carcinoma Cells

Oral squamous cell carcinoma (OSCC) is a leading cause of cancer-related deaths worldwide. It has a very poor prognosis with over a 5-year survival rate of only 50%. Thus, it is important to identify effective therapeutic interventions against oral cancer. Apoptosis and autophagy have reported genetically regulated in physiology and diseases, which close relationship. Many natural compound study objects anticancer effect have been studied between apoptosis and autophagy relationship. The present study was designed to evaluate the effect of erianin on human oral cancer cell proliferation. Results of the study revealed that treatment with erianin significantly reduced the viability of different OSCC cell lines. Erianin exerted its cytotoxic effect by inducing cell cycle arrest and caspase-dependent apoptotic pathways. Both intrinsic and extrinsic pathways were found to be involved in erianin-mediated cell death. In addition, treatment with erianin also increased autophagy in OSCC cells. With further analysis, it was found that erianin induced both apoptosis and autophagy by regulating MAPK signaling pathways. Taken together, our study indicates that erianin plays an important role in reducing oral cancer cell viability, and thus, can be considered as a potential anticancer agent.

S. Pattern-Corrected Mitotic Activity Index (PMAI): A Novel Prognosticator of Oral Squamous Cell Carcinoma

OBJECTIVE

The main aim was to assess the efficiency of the Mitotic Activity Index (MAI) and a novel index devised by us, the Pattern-Corrected Mitotic Activity Index (PMAI) in prognostication of Oral Squamous Cell Carcinoma in terms of lymph node involvement, margin, recurrence and survival status.

MATERIAL AND METHOD

The study group consisted of 60 cases of histologically-proven Oral Squamous Cell Carcinoma with known status of prognostic indicators. Hematoxylin and eosin stained sections of the tumor proper were utilized for assessment of mitotic activity and pattern of invasion. The Mitotic Activity Index and Pattern-Corrected Mitotic Activity Index were then calculated and correlated with the prognosticators.

RESULTS

Mitotic Activity Index was higher in patients who had better survival and low recurrence rates. Pattern-Corrected Mitotic Activity Index showed the greatest percentage increase in relation to lymph node involvement as compared to the other indices. Kaplan Meier survival analysis showed that a higher Pattern-Corrected Mitotic Activity Index ( > 1.45) was associated with poorer survival (37.19 months).

CONCLUSION

Lack of significant association of the Mitotic Activity Index in relation to prognosticators could be attributed to a tumor having a migratory phenotype rather than a proliferative phenotype as seen in late-stage tumors. Late-stage tumors have more of a poorer pattern of invasion which is reflected best by Pattern-Corrected Mitotic Activity Index by correlating with poorer survival and lymph node involvement.

One-bead one-compound combinatorial library derived targeting ligands for detection and treatment of oral squamous cancer

Oral squamous cancers (OSC) are hallmarked by poor prognosis, delayed clinical detection, and a lack of defined, characteristic biomarkers. By screening combinatorial one-bead one-compound (OBOC) peptide libraries against oral squamous cancer cell lines, two cyclic peptide ligands, LLY12 and LLY13 were previously identified. These ligands are capable of specific binding to the oral cancer cell lines (MOK-101, HSC-3, SCC-4 and SCC-10a) but not non-cancerous keratinocytes, leukocytes, fibroblast, and endothelial cells. These two peptides were synthesized and evaluated for their binding property, cytotoxicity and cell permeability. In vitro studies indicate that both LLY12 and LLY13 were able to bind to oral cancer cells with high specificity but did not show any cytotoxicity against human keratinocytes. Biotinylated LLY13, in complex with streptavidin-alexa488 was taken up by live oral cancer cells, thus rendering it as an excellent candidate vehicle for efficient delivery of drug loaded-nanoparticles. In vivo and ex vivo near infra-red fluorescence imaging studies confirmed the in vivo targeting efficiency and specificity of LLY13 in oral cancer orthotopic murine xenograft model. In vivo studies also showed that LLY13 was able to accumulate in the OSC tumors and demarcate the tumor margins in orthotopic xenograft model. Together, our data supports LLY13 as a promising theranostic agent against OSC.

An immunohistochemical evaluation of podoplanin expression in oral leukoplakia and oral squamous cell carcinoma to explore its potential to be used as a predictor for malignant transformation

Background

Oral leukoplakia (OL) is a potentially malignant disorder with increased risk for the development of oral squamous cell carcinoma (OSCC). Many cases of OSCC arise from the malignant transformation of preexisting OL. However, the risk of progression into OSCC and the possible prediction of malignant potential of OL remain inconclusive. Recent studies have shown that podoplanin, a mucin-like transmembrane glycoprotein specifically expressed in lymphatic endothelial cells, is expressed in various neoplasms including OSCC, indicating its possible biologic role in tumor cells. In this study, an evaluation of podoplanin expression in OL and OSCC has been carried out to assess its potential role as a biomarker to predict the possibility of malignant transformation in OL cases.

Aims and Objectives

To assess the usefulness of podoplanin as a potential biomarker for predicting the risk of malignant transformation in OL, by comparing its immunohistochemical expression in OL and OSCC.

Materials and Methods

Archival paraffin-embedded blocks of 25 OL cases with varying grades of dysplasia and 30 OSCC cases showing its varying grades were selected. Sections were subjected to immunohistochemical staining for podoplanin and compared with the control group for evaluation of results in the three groups.

Results

A statistically significant increase in podoplanin expression was observed from normal mucosa through OL to OSCC. In the OL cases, the podoplanin staining score progressively increased from mild dysplasia to carcinoma in situ, whereas in OSCC, well-differentiated group showed the maximum expression of podoplanin.

Conclusion

The progressive increase in podoplanin expression through the increasing grades of dysplasia in OL is suggestive of an increased risk for malignant transformation with increased expression of podoplanin in OL cases. A high podoplanin expression in the well-differentiated OSCC may indicate a vital role for podoplanin in the early stages of tumorigenesis.

Tumor Budding and Worse Pattern of Invasion Can Predict Nodal Metastasis in Oral Cancers and Associated With Poor Survival in Early-Stage Tumors

The management and prognosis of oral squamous cell carcinoma (OSCC) depend on tumor stage and lymph node (LN) metastasis status. Early-stage (T1/T2 N0M0) OSCC comprises a heterogeneous group. We evaluated the role of histological parameters including worst pattern of invasion (WPOI) and tumor budding to determine the risk of LN metastasis in cases of OSCC and to determine the risk of recurrence and death in early-stage OSCC in north Indian patients. All cases of buccal mucosa and tongue SCC which underwent excision over 4 and half years were reviewed for histological parameters including histologic grade, WPOI, tumor budding, lymphovascular emboli (LVE), perineural invasion (PNI), depth of invasion (DOI), host lymphocyte response, and stromal response and compared to LN metastasis. Clinical follow-up of early-stage tumor was obtained and compared. A total of 126 cases of OSCC were included, of which 48 showed LN metastasis. Histological grade, WPOI, tumor budding (≥3/×40 field), LVE, and PNI were significantly associated with risk of LN metastasis. On multivariate analysis, WPOI and tumor budding were 2 most significant factors. Among the early-stage tumors with available follow up (n = 48), DOI, WPOI, tumor budding, and LVE were associated with a shorter overall survival, although it was not statistically significant. To conclude, WPOI and tumor budding are important risk factors for predicting LN metastasis in all stages of OSCC and associated with a poorer outcome in early-stage tumors. These are easy and reliable prognostic factors and should be included in the histopathological reporting guidelines.

Depth-resolved birefringence imaging of collagen fiber organization in the human oral mucosa in vivo

Stromal collagen organization has been identified as a potential prognostic indicator in a variety of cancers and other diseases accompanied by fibrosis. Changes in the connective tissue are increasingly considered for grading dysplasia and progress of oral squamous cell carcinoma, investigated mainly ex vivo by histopathology. In this study, polarization-sensitive optical coherence tomography (PS-OCT) with local phase retardation imaging is used for the first time to visualize depth-resolved (i.e., local) birefringence of healthy human oral mucosa in vivo. Depth-resolved birefringence is shown to reveal the expected local collagen organization. To demonstrate proof-of-principle, 3D image stacks were acquired at labial and lingual locations of the oral mucosa, chosen as those most commonly affected by cancerous alterations. To enable an intuitive evaluation of the birefringence images suitable for clinical application, color depth-encoded en-face projections were generated. Compared to en-face views of intensity or conventional cumulative phase retardation, we show that this novel approach offers improved visualization of the mucosal connective tissue layer in general, and reveals the collagen fiber architecture in particular. This study provides the basis for future prospective pathological and comparative in vivo studies non-invasively assessing stromal changes in conspicuous and cancerous oral lesions at different stages.

A Pilot Clinical Study on the Prognostic Relevance of Plasmatic Exosomes Levels in Oral Squamous Cell Carcinoma Patients

Background: To evaluate the relationship between the plasmatic CD63 and CAV1 positive exosome levels, in patients with OSCC before and after surgical treatment and to correlate it with their overall survival. Methods: A double-blind pilot study over 10 patients OSCC and T4 stage without distant metastases or local bone invasion has been performed. The average follow-up period was 37.64 months (34.3–40.84). We obtained 2 plasma tubes of 1 mL each before surgery and 7 days after surgery. Before performing the immunocapture-based analysis, EVs (Extracellular Vesicles) were isolated from the plasma and characterized with western blot analysis. Results: Mean values of CD63 positive plasmatic exosomes (EXO-CD63) after surgery decreased from 750.88 ± 286.67 to 541.71 ± 244.93 (p = 0.091). On the other hand, CAV-1 positive plasmatic exosomes (EXO-CAV-1) increased after surgery from 507 ± 483.39 to 1120.25 ± 1151.17 (p = 0.237). Patients with EXO-CD63 levels lower than the mean global value before the surgery had a survival of 36.04 months compared with the group with EXO-CD63 higher than the average who only survived 12.49 ± 1.67 months from the diagnosis, p = 0.225. When EXO-CAV-1 levels before surgery was lower than the average (813.94 ± 801.21) overall survival was 24.69 ± 22.23 months in contrast when it was higher that was only 11.64 months, p = 0.157. Patients with lower EXO-CD63 levels after surgery lived an average of 23.84 ± 23.9 months, while those with higher plasmatic levels of EXO-CD63 live 13.35 months, p = 0.808. When EXO-CAV-1 levels after surgery were lower, the average overall survival was 20.344 ± 15.40 months, in contrast when the EXO-CAV-1 levels were higher showing rather an estimate survival expectation of 1.64 months. Conclusions: Surgical treatment induced a dramatic reduction of the plasmatic levels of exosomes expressing CD63 as early as 1 week after resection. This first result suggests that the tumour mass is responsible of the high levels of circulating exosomes detected in cancer patients. At the same time point exosome expressing CAV-1 increased, possibly due to the inflammatory reaction immediately after surgery. Lastly, statistical analysis showed that lower levels of plasmatic exosomes both before and after surgery correlated with a better life expectancy of OSCC patients. Hopefully, this approach will prove useful in the clinical follow-up of cancer patients.

Oxidative Stress and Oral Mucosal Diseases: An Overview

BACKGROUND

Reactive oxygen species (ROS) and free radicals are physiologically produced during cellular metabolism. When their balance is disrupted in favor of ROS, a condition called oxidative stress occurs. Oxidative stress represents a widespread phenomenon involved in several pathological conditions. The aim of the present review was to report current knowledge on oxidative stress related to oral mucosal diseases.

MATERIALS AND METHODS

Articles from 2000 to 2018 were selected for relevance, validity and quality, from results obtained in PubMed, MEDLINE and Google Scholar using the following search terms: oxidative stress and oral lichen, oral pemphigus, aphthous stomatitis, oral leukoplakia, oral cancer, oral squamous cell carcinoma and oral carcinoma. All articles were independently screened for eligibility by the authors.

RESULTS

This narrative review integrates extensive information from all relevant published studies focusing on oxidative stress in oral mucosal diseases. We outline the pathogenetic function of oxidative stress in the most frequent inflammatory, potentially malignant and malignant diseases of the oral mucosa and provide detailed findings from human research.

CONCLUSION

Although variability in findings between individual studies exists, it justifies the conclusion that oxidative stress is a significant process in the oral mucosal diseases pathogenesis.