Correlation between Vascularity and Advancing Histological Grades of Oral Submucous Fibrosis with a Plausible Role in Malignisation: Systematic review of a persisting matter of conflict.

Objectives: This study aimed to quantify the vascularity in histological grades of oral submucous fibrosis (OSMF) and to determine if there is any connection between vasculogenesis and malignisation. Recent studies show no significant change in vascularity as the stage advances as opposed to the conventional concept. Methods: A comprehensive database search until December 2022 was conducted for published articles on vascularity in OSMF following preferred reporting items for systematic reviews and meta-analyses guidelines. Results: A total of 98 articles were screened of which 13 were included for systematic evaluation. The study included 607 cases, with a definite predilection for the male gender. Of the 13 studies, 11 evaluated mean vascular density. In more than half of the studies, the vascularity decreased as the stage advanced. Similar results were obtained for endothelial cells/µm2, mean vascular area percentage and mean vascular area. Conclusion: The present review supports the prevailing concept that vascularity decreases with the advancement of the OSMF stage. This denies the systemic absorption of carcinogens into the circulation with resultant longer exposure of compromised epithelium and malignisation.

Resveratrol nanoparticles induce apoptosis in oral cancer stem cells by disrupting the interaction between ß-catenin and GLI-1 through p53-independent activation of p21.

Cancer stem cells (CSCs) are mainly responsible for tumorigenesis, chemoresistance, and cancer recurrence. CSCs growth and progression are regulated by multiple signaling cascades including Wnt/ß-catenin and Hh/GLI-1, which acts independently or via crosstalk. Targeting the crosstalk of signaling pathways would be an effective approach to control the CSC population. Both Wnt/ß-catenin and Hh/GLI-1 signaling cascades are known to be regulated by p53/p21-dependent mechanism. However, it is interesting to delineate whether p21 can induce apoptosis in a p53-independent manner. Therefore, utilizing various subtypes of oral CSCs (SCC9-PEMT p53+/+p21+/+, SCC9-PEMT p53-/-p21+/+, SCC9-PEMT p53+/+p21-/- and SCC9-PEMT p53-/-p21-/-), we have examined the distinct roles of p53 and p21 in Resveratrol nanoparticle (Res-Nano)-mediated apoptosis. It is interesting to see that, besides the p53/p21-mediated mechanism, Res-Nano exposure also significantly induced apoptosis in oral CSCs through a p53-independent activation of p21. Additionally, Res-Nano-induced p21-activation deregulated the ß-catenin-GLI-1 complex and consequently reduced the TCF/LEF and GLI-1 reporter activities. In agreement with in vitro data, similar experimental results were obtained in in vivo mice xenograft model.

Prognostic importance of modified geriatric nutritional risk index in oral cavity squamous cell carcinoma.

We probed the associations of preoperative modified geriatric nutritional risk index (mGNRI) values with prognosis in patients receiving surgery for oral cavity squamous cell carcinoma (OCSCC). This retrospective study analyzed the clinical data of 333 patients with OCSCC and undergoing surgery between 2008 and 2017. The preoperative mGNRI was calculated using the following formula: (14.89/C-reactive protein level) + 41.7 × (actual body weight/ideal body weight). We executed receiver operating characteristic curve analyses to derive the optimal mGNRI cutoff and employed Kaplan-Meier survival curves and Cox proportional hazard model to probe the associations of the mGNRI with overall survival (OS) and disease-free survival (DFS). The optimal mGNRI cutoff was derived to be 73.3. We noted the 5-year OS and DFS rates to be significantly higher in the high-mGNRI group than in the low-mGNRI group (both p < 0.001). A preoperative mGNRI below 73.3 was independently associated with unfavorable DFS and OS. A mGNRI-based nomogram was constructed to provide accurate OS predictions (concordance index, 0.781). Hence, preoperative mGNRI is a valuable and cost-effective prognostic biomarker in patients with OCSCC. Our nomogram facilitates the practical use of mGNRI and offers individualized predictions of OS.

Survival estimation of oral cancer using fuzzy deep learning.

BACKGROUND: Oral cancer is a deadly disease and a major cause of morbidity and mortality worldwide. The purpose of this study was to develop a fuzzy deep learning (FDL)-based model to estimate the survival time based on clinicopathologic data of oral cancer. METHODS: Electronic medical records of 581 oral squamous cell carcinoma (OSCC) patients, treated with surgery with or without radiochemotherapy, were collected retrospectively from the Oral and Maxillofacial Surgery Clinic and the Regional Cancer Center from 2011 to 2019. The deep learning (DL) model was trained to classify survival time classes based on clinicopathologic data. Fuzzy logic was integrated into the DL model and trained to create FDL-based models to estimate the survival time classes. RESULTS: The performance of the models was evaluated on a test dataset. The performance of the DL and FDL models for estimation of survival time achieved an accuracy of 0.74 and 0.97 and an area under the receiver operating characteristic (AUC) curve of 0.84 to 1.00 and 1.00, respectively. CONCLUSIONS: The integration of fuzzy logic into DL models could improve the accuracy to estimate survival time based on clinicopathologic data of oral cancer.

F. Nucleatum enhances oral squamous cell carcinoma proliferation via E-cadherin/ß-Catenin pathway.

BACKGROUND: Fusobacterium nucleatum (F. nucleatum) is a microbial risk factor whose presence increases the risk of oral squamous cell carcinoma (OSCC) progression. However, whether it can promote the proliferation of OSCC cells remains unknown. METHODS: In this study, we investigated F. nucleatum effect on OSCC cell proliferation using in vitro and in vivo experiments. RESULTS: Our results showed that F. nucleatum promoted OSCC cell proliferation, doubling the cell count after 72 h (CCK-8 assay). Cell cycle analysis revealed G2/M phase arrest. F. nucleatum interaction with CDH1 triggered phosphorylation, upregulating downstream protein ß-catenin and activating cyclinD1 and Myc. Notably, F. nucleatum did not affect noncancerous cells, unrelated to CDH1 expression levels in CAL27 cells. Overexpression of phosphorylated CDH1 in 293T cells did not upregulate ß-catenin and cycle-related genes. In vivo BALB/c nude experiments showed increased tumor volume and Ki-67 proliferation index after F. nucleatum intervention. CONCLUSION: Our study suggests that F. nucleatum promotes OSCC cell proliferation through the CDH1/ß-catenin pathway, advancing our understanding of its role in OSCC progression and highlighting its potential as a therapeutic target.

Extracellular vesicles from Aggregatibacter actinomycetemcomitans exhibit potential antitumorigenic effects in oral cancer: a comparative in vitro study.

Aggregatibacter actinomycetemcomitans is an opportunistic Gram-negative periodontopathogen strongly associated with periodontitis and infective endocarditis. Recent evidence suggests that periodontopathogens can influence the initiation and progression of oral squamous cell carcinoma (OSCC). Herein we aimed to investigate the effect of A. actinomycetemcomitans-derived extracellular vesicles (EVs) on OSCC cell behavior compared with EVs from periodontopathogens known to associate with carcinogenesis. EVs were isolated from: A. actinomycetemcomitans and its mutant strains lacking the cytolethal distending toxin (CDT) or lipopolysaccharide (LPS) O-antigen; Porphyromonas gingivalis; Fusobacterium nucleatum; and Parvimonas micra. The effect of EVs on primary and metastatic OSCC cells was assessed using cell proliferation, apoptosis, migration, invasion, and tubulogenesis assays. A. actinomycetemcomitans-derived EVs reduced the metastatic cancer cell proliferation, invasion, tubulogenesis, and increased apoptosis, mostly in CDT- and LPS O-antigen-dependent manner. EVs from F. nucleatum impaired the metastatic cancer cell proliferation and induced the apoptosis rates in all OSCC cell lines. EVs enhanced cancer cell migration regardless of bacterial species. In sum, this is the first study demonstrating the influence of A. actinomycetemcomitans-derived EVs on oral cancer in comparison with other periodontopathogens. Our findings revealed a potential antitumorigenic effect of these EVs on metastatic OSCC cells, which warrants further in vivo investigations.

Challenges in the Assessment of Medullary Bone Invasion in Oral Cavity Cancers and Its Prognostic Significance.

BACKGROUND: As per AJCC 8th edition TNM staging system, bone invasion is a poor prognostic marker that upstages oral cavity squamous carcinoma (OSCC) to pT4a. Cortical erosion alone of bone or tooth socket by a gingival primary is not sufficient to upstage a tumour. The differentiation of cortical erosion from invasion through the cortical bone into the medulla is often challenging, limiting accurate staging. This review aims to assess the difficulties in differentiating cortical erosion from medullary invasion and evaluate the prognostic significance of different patterns of bone involvement. METHODS: A retrospective review of OSCC with primary curative surgery and bone resection treated at a single-center over 10 years, was performed to assess the prognostic significance of bone invasion. Hematoxylin-eosin stained slides of a subset of cases were re-reviewed in a planned manner to assess difficulties in precise categorization (no invasion/erosion/cortical invasion and medullary invasion), evaluate interobserver agreement, and correlate with clinical outcome. RESULTS: Five hundred and ninety patients were included, with a median follow-up of 28 months. On univariate analysis, the 3-year local, nodal and distant metastasis control were not significantly different in the 3 groups of no invasion, erosion, and invasion (p = 0.43, 0.47, and 0.47, respectively). Overall survival (OS) at 3 years was 78.1% and disease-free-survival(DFS) was 63.7% in the entire cohort. On univariate analysis, there was significant difference in OS and DFS based on these groups. This did not translate into independent prognostic benefit on multivariable analysis (p = 0.75 and 0.19, respectively). The independent prognostic factors were margin positivity, tumor differentiation, perineural invasion and pathological nodal involvement. Planned re-review of a subset of 202 cases resulted in a change in bone involvement category in 26/202 cases, which was mainly due to difficulty in assessing cortico-medullary junction near the tooth socket and bone fragmentation. The assessment showed moderate to near complete agreement (kappa 0.59-0.82) between 2 observers. CONCLUSION: Our study shows that bone involvement is not an independent prognostic marker and there is no specific correlation of medullary invasion with outcome over those that showed cortical erosion. Several factors contribute to difficulties and interobserver variability in assessing bone involvement.

In Response to "Acute Oral Mucositis During Hypo-Fractionated Radiation in Squamous Cell Carcinoma of Oral Cavity".

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Periodontitis and the risk of oral cancer: a meta-analysis of case-control studies.

OBJECTIVE: The current studies have yielded inconclusive findings regarding the connection between periodontitis  and oral cancer (OC). Therefore, our goal is to elucidate this relationship. MATERIALS AND METHODS: We conducted a thorough search of electronic databases (EMBASE, PubMed, Web of Science, and Cochrane Library) up to September 2023. The Newcastle-Ottawa Scale (NOS) was applied to assess study quality. To evaluate potential publication bias, both a funnel plot and Egger's test were employed. Additionally, a sensitivity analysis was conducted to explore the source of heterogeneity when the I2 statistic exceeded 50%. RESULTS: This systematic review encompassed 16 studies, involving a total of 6,032 OC patients and 7,432 healthy controls. Our meta-analysis, incorporating data from nine studies, revealed a significant correlation between periodontitis and the risk of OC (OR [odds ratio] = 2.94, 95% CI [confidence interval] (2.13, 4.07); five studies, 6,927 participants; low certainty of evidence). Findings also suggested that individuals with more than 15 missing teeth may have a heightened risk of OC (OR = 1.91, 95% CI (1.01, 3.62)). Furthermore, clinical attachment loss (CAL) and decayed, missing, and filled teeth (DMFT) in OC patients were more pronounced compared to the control group (CAL, SMD = 1.94, 95% CI (0.22, 3.66); DMFT, SMD = 0.65, 95% CI (0.12, 1.18)). CONCLUSION: Periodontitis may serve as a potential risk factor for OC. However, caution is warranted in interpreting these findings due to the substantial level of heterogeneity.

[Precancers of the oral mucosa: clinic, diagnostics]. / Predraki slizistoi obolochki rta: klinika i diagnostika.

OBJECTIVE: The aim of the study. Improving the efficiency of diagnosis and detailing the features of the clinic of «potentially malignant¼ diseases of the oral mucosa. MATERIALS AND METHODS: Clinical and laboratory examination of 124 patients of the department of oral mucosa diseases aged 35 to 80 years, among whom there were 75 women and 49 men, with diseases such as erythroplakia - 12 patients, verrucous leukoplakia - 52 patients, erosive form of leukoplakia - 35 patients, cheilitis Manganotti - 25 patients. Histological and immunohistochemical methods of investigation were used as diagnostics. To assess the proliferative activity of epithelial cells, the determination of the Ki-67 index was used. The synthesis of keratin 15 (K15) in epithelial layers was determined as a diagnostic criterion for the severity of neoplasia. The expression of human papillomavirus type 16 (HPV 16) antigens and p16INK4a protein in epithelial cells was studied, as well as the expression of p53 protein. RESULTS: A high prevalence of p53 mutations was observed in patients with erythroplakia. In leukoplakia, the expression of the Ki-67 protein was detected in the cell nuclei in both the basal and parabasal layers of the multilayer squamous epithelium, in 77% of cases, the expression of the p16INK4a protein in the epithelial nuclei with varying degrees of dysplastic changes was noted, and a positive reaction to HPV16 was also observed in the cell nuclei and cytoplasm of epithelial cells in the basal, parabasal and spiny epithelial layers. The appearance of K15 in the cytoplasm of cells above the basal layer with abrasive precancerous cheilitis was found in 48% of cases. CONCLUSION: To diagnose early manifestations of neoplastic processes in «potentially malignant¼ diseases of the oral mucosa, it is necessary to use both classical histological and immunohistochemical methods of investigation with various markers.

Role of Mutation of NOTCH1 gene in development of oral squamous cell carcinoma: a narrative review.

Cancer of the oral cavity has numerous types and, among all, oral squamous cell carcinoma represents >90% of all cancers of the oral area. Oral squamous cell carcinoma arises from the squamous lining of the oral cavity. Across the globe, most commonly it develops in the regions of tongue followed by floor of the mouth, and lower lip. Neurogenic locus notch homolog protein 1 gene has its association with oral squamous cell carcinoma and is known to be associated with both oncogenic and tumour suppressor roles. The current narrative review comprised literature published from 2013 to 2023. It was searched on Google Scholar, PubMed and Google databases. Globally, neurogenic locus notch homolog protein 1 mutations are associated with the development of oral squamous cell carcinoma. Most of the mutations are linked to ligand bind epidermal growth factor-like repeat region of extracellular domain of neurogenic locus notch homolog protein 1. Once activated, the pathway is involved in tumour progression and metastasis. The Asians compared to Caucasians are more affected by neurogenic locus notch homolog protein 1 mutations.

Beneath the surface: A systematic review on intraoperative imaging techniques for deep margin assessment in oral squamous cell carcinoma.

Resection margins of oral squamous cell carcinoma (SCC) are often inadequate. A systematic review on clinical intraoperative whole-specimen imaging techniques to obtain adequate deep resection margins in oral SCC is lacking. Such a review may render better alternatives for the current insufficient intraoperative techniques: palpation and frozen section analyses (FSA). This review resulted in ten publications investigating ultrasound (US), four investigating fluorescence, and three investigating MRI. Both US and fluorescence were able to image the tumor intraorally and perform ex-vivo imaging of the resection specimen. Fluorescence was also able to image residual tumor tissue in the wound bed. MRI could only be used on the ex-vivo specimen. The 95 % confidence intervals for sensitivity and specificity were large, due to the small sample sizes for all three techniques. The sensitivity and specificity of US for identifying < 5 mm margins ranged from 0 % to 100 % and 60 % to 100 %, respectively. For fluorescence, this ranged from 0 % to 100 % and 76 % to 100 %, respectively. For MRI, this ranged from 7 % to 100 % and 81 % to 100 %, respectively. US, MRI and fluorescence are the currently available imaging techniques that can potentially be used intraoperatively and which can image the entire tumor-free margin, although they have insufficient sensitivity for identifying < 5 mm margins. Further research on larger cohorts is needed to improve the sensitivity by determining cut-off points on imaging for inadequate margins. This improves the number of adequate resections of oral SCC's and pave the way for routine clinical implementation of these techniques.

N0 neck trial: Does intensification of follow-up (Ultrasound + Physical Examination) influence outcomes in early-stage oral cancer?

AIM OF THE STUDY: We previously reported a survival benefit of elective neck dissection (END) over therapeutic neck dissection (TND) in patients with clinically node-negative early-stage oral cancer. We now report the results of the second question in the same study addressing the impact of adding neck ultrasound to physical examination during follow-up on outcomes. METHODS: Patients with lateralized T1/T2 oral squamous cell carcinoma (SCC) were randomized to END or TND and to follow-up with physical-examination plus neck ultrasound (PE+US) versus physical-examination (PE). The primary endpoint was overall survival (OS). RESULTS: Between January 2004 and June 2014, 596 patients were enrolled. This is an intention to treat analysis of 592 analysable patients, of whom 295 were allocated to PE+US and 297 to PE with a median follow-up of 77.47 months (interquartile range (IQR) 54.51-126.48). There was no significant difference (unadjusted hazard ratio [HR], 0.92, 95% CI, 0.71-1.20, p = 0.54) in 5-year OS between PE+US (70.8%, 95% CI, 65.51-76.09) and PE (67.3%, 95% CI, 61.81-72.79). Among 131 patients with neck node relapse as the first event, the median time to relapse detection was 4.85 (IQR 2.33-9.60) and 7.62 (IQR 3.22-9.86) months in PE+US and PE arms, respectively. The N stage in the PE+US arm was N1 33.8%, N2a 7.4%, N2b/c 44.1% and N3 14.7% while in PE was N1 28.6%, N2a 9.5%, N2b/c 39.7%, N3 20.6% and unknown 1.6%. CONCLUSION: Adding neck ultrasound to physical examination during follow-up detects nodal relapses earlier but does not improve overall survival.

Addition of tumor microenvironment immune cell composition to improve the performance of a predictive model for oral squamous cell carcinoma.

BACKGROUND: Conventional clinicopathological characteristics insufficiently predict prognosis in oral squamous cell carcinoma (OSCC). We aimed to assess the added predictive value of tumor microenvironment immune cell composition (TMICC) in addition to conventional clinicopathological characteristics. METHODS: Primary tumor samples of 290 OSCC patients were immunohistochemically stained for CD4, CD8, CD20, CD68, CD163, CD57, FoxP3 and Programmed cell Death Ligand 1. Additionally, clinicopathological characteristics were obtained from patients' medical files. Predictive models were trained and validated by conducting Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses with cross-validation. To quantify the added predictive power of TMICC within models, receiver operating characteristic (ROC) analyses were used. RESULTS: Recurrence occurred in 74 patients (25.5%). Conventional clinicopathological characteristics (tumor localization, pathological T-stage, pathological N-stage, extracapsular spread, resection margin, differentiation grade, perineural invasion, lymphovascular invasion) and treatment modality, were used to build a LASSO logistic regression-based predictive model. Addition of TMICC to the model resulted in a comparable AUC of respectively 0.79 (±0.01) and 0.76 (±0.1) in the training and test sets. The model indicated that high numbers of CD4+ T cells protected against recurrence. Lymph node metastasis, extracapsular spread, perineural invasion, positive surgical margins and reception of adjuvant treatment were associated with increased risk for recurrence. CONCLUSIONS: The TMICC, specifically the number of CD4+ T cells, is an independent predictor , however, addition to conventional clinicopathological characteristics does not improve the performance of a predictive model for recurrence in OSCC.

EP4-induced mitochondrial localization and cell migration mediated by CALML6 in human oral squamous cell carcinoma.

Lymph node metastasis, primarily caused by the migration of oral squamous cell carcinoma (OSCC) cells, stands as a crucial prognostic marker. We have previously demonstrated that EP4, a subtype of the prostaglandin E2 (PGE2) receptor, orchestrates OSCC cell migration via Ca2+ signaling. The exact mechanisms by which EP4 influences cell migration through Ca2+ signaling, however, is unclear. Our study aims to clarify how EP4 controls OSCC cell migration through this pathway. We find that activating EP4 with an agonist (ONO-AE1-473) increased intracellular Ca2+ levels and the migration of human oral cancer cells (HSC-3), but not human gingival fibroblasts (HGnF). Further RNA sequencing linked EP4 to calmodulin-like protein 6 (CALML6), whose role remains undefined in OSCC. Through protein-protein interaction network analysis, a strong connection is identified between CALML6 and calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), with EP4 activation also boosting mitochondrial function. Overexpressing EP4 in HSC-3 cells increases experimental lung metastasis in mice, whereas inhibiting CaMKK2 with STO-609 markedly lowers these metastases. This positions CaMKK2 as a potential new target for treating OSCC metastasis. Our findings highlight CALML6 as a pivotal regulator in EP4-driven mitochondrial respiration, affecting cell migration and metastasis via the CaMKK2 pathway.

Systematic review of minimally-invasive reconstructive options for oral cavity defects.

The oral cavity is a primary site for malignant neoplasms of the head and neck region. Surgery, with or without adjuvant therapy, offers the highest probability of cure by focusing on radical tumour removal and organ function restoration. Reconstructive options are represented by local and free flaps, while small defects can be managed without reconstruction. For medium-sized defects without bone involvement, local flaps can be a good alternative to free flaps in selected patients. The purposes of this article are to analyse the main minimally-invasive reconstructive techniques in oral cancer surgery through a systematic review of the literature and develop a reconstructive algorithm based on the site and size of the defect. We defined minimally-invasive reconstruction as any reconstructive option not involving flap dissection from the neck or other distant areas from the oral cavity. Options considered include: local myo-mucosal or mucosal flaps (based on the facial or buccal arteries, and palatal flap), Bichat's fat pad flap, and nasolabial flap. Use of biological or synthetic materials is also described. In selected patients with small to moderate-sized defects, the possibility of reconstruction with local flaps can be a viable option.

Diagnostic accuracy of contrast-enhanced computed tomography in assessing bone invasion in patients with oral squamous cell carcinoma.

OBJECTIVES: This study aimed to evaluate the diagnostic accuracy of contrast-enhanced computed tomography (CT) in detecting bone invasion in oral squamous cell carcinoma (OSCC) patients and to explore clinicopathological factors associated with its reliability. MATERIALS AND METHODS: 417 patients underwent preoperative contrast-enhanced CT followed by radical surgery. The presence or absence of bone invasion served as the outcome variable, with histopathologic examination of the resection specimen considered the gold standard. Statistical analyses, comprising correlation analyses and the determination of sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV), were conducted. RESULTS: CT exhibited 76.85% sensitivity, 82.20% specificity, 47.14% PPV, and 89.67% NPV. False-positive and false-negative rates were 11.27% and 5.99%, respectively. Artifacts affected assessment in 44 patients, but not in those with bone invasion. Tumor size, depth of invasion (DOI), tumor localization at the upper jaw, lymphatic invasion, and perineural invasion correlated with incorrect identification of bone invasion (Chi-square, p < 0.05). CONCLUSIONS: Despite utilizing thin-section CT, notable false-positive and false-negative results persisted. Patients with T3 tumors, DOI ≥ 10 mm, or upper jaw tumors are at higher risk for misidentification of bone invasion. Combining multiple methods may enhance diagnostic accuracy, and the integration of artificial intelligence or tracking electrolyte disturbances by tumor depth profiling shows promise for further assessment of bone invasion before histopathology. CLINICAL RELEVANCE: Surgeons should consider these insights when planning tumor resection. Supplementary imaging may be warranted in cases with high risk factors for misidentification. Further methodological advancements are crucial for enhancing diagnostic precision.