Oral inflammation promotes oral squamous cell carcinoma invasion

Basement membrane-associated gene expression as a predictor of survival in oral cancer

BACKGROUND

This study sought to investigate the prognostic value of basement membrane (BM)-associated gene expressions in oral cancer.

METHODS

We harvested and integrated data on BM-associated genes (BMGs), the oral cancer transcriptome, and clinical information from public repositories. After identifying differentially expressed BMGs, we used Cox and Lasso regression analyses to create a BMG-based risk score for overall survival at various intervals. We then validated this score using the GSE42743 cohort as a validation set. The prognostic potential of the risk scores and their relations to clinical features were assessed. Further, we conducted functional pathway enrichment, immune cell infiltration, and immune checkpoint analyses to elucidate the immunological implications and therapeutic potential of the BMG-based risk score and constituent genes. To confirm the expression levels of the BMG LAMA3 in clinical samples of oral cancer tissue, we performed quantitative real-time PCR (qRT-PCR) and immunohistochemical staining.

RESULTS

The BMGs LAMA3, MMP14, and GPC2 demonstrated notable prognostic significance, facilitating the construction of a BMG-based risk score. A higher risk score derived from BMGs correlated with a poorer survival prognosis for oral cancer patients. Moreover, the risk-associated BMGs exhibited a significant relationship with immune function variability (P < 0.05), discrepancies in infiltrating immune cell fractions, and immune checkpoint expressions (P < 0.05). The upregulated expression levels of LAMA3 in oral cancer tissues were substantiated through qRT-PCR and immunohistochemical staining.

CONCLUSION

The BMG-based risk score emerged as a reliable prognostic tool for oral cancer, meriting further research for validation and potential clinical application.

Tumor microenvironment of ameloblastoma with a focus on osteoclastogenesis, cell migration, and malignant transformation

BACKGROUND

Odontogenic tumors arise in the jawbone and originate from cells associated with tooth development. Therefore, understanding odontogenic tumors requires knowledge of all aspects of dental research, including tooth development and eruption. Ameloblastoma is the most common odontogenic tumor.

HIGHLIGHT

Although a benign tumor, ameloblastoma progresses with marked jawbone resorption. Because of its locally aggressive features, it can be treated surgically by resecting the surrounding bone. From a molecular pathology perspective, several genetic mutations and dysregulated signaling pathways involved in ameloblastoma tumorigenesis have been identified. Histopathologically, ameloblastomas consist of peripheral ameloblast-like cells and an inner stellate reticulum. The stromal region consists of fibrovascular connective tissue, showing a characteristic sparse myxoid histology. In general, the tumor microenvironment, including the surrounding non-tumor cells, contributes to tumorigenesis and progression. In this review, we focus on the tumor microenvironment of ameloblastomas. In addition, we present some of our recent studies on osteoclastogenesis, tubulin acetylation-induced cell migration, and hypoxia-induced epithelial-mesenchymal transition in ameloblastomas.

CONCLUSION

Further research on ameloblastomas can lead to the development of new treatments and improve patients' quality of life.

Up-regulation of extracellular-matrix and inflammation related genes in oral squamous cell carcinoma

OBJECTIVE

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy with late-presentation, site-specific heterogeneity, and high-propensity for recurrence/metastasis that has shown rise in mortality. Lately, research emphasize on dynamic interactions between tumor-cells and extracellular-matrix components within tumor-microenvironment that promote tissue integrity loss and carcinogenesis. Therefore, OSCC clinical-management is still challenging.

DESIGN

Present study validated clinical utility of a 13 gene-panel in two chief sub-sites of OSCC: Buccal mucosa squamous cell carcinoma (BMSCC) (N = 50) and Tongue squamous cell carcinoma (TSCC) (N = 52) using qRT-PCR. Principal component analysis and binary logistic regression analysis were applied to acquire definite multi gene models. Protein expression analysis was employed using the Human Protein Atlas, UALCAN and TIMER 2.0 databases to explore potential correlation between immune cells and gene-panels.

RESULTS

Significant up-regulation of CXCL8, CXCL10, FN1, GBP1, IFIT3, ISG15, MMP1, MMP3, MMP10, PLAU, SERPINE1 and SPP1 except OASL was observed in OSCC tissue in comparison of absolute normal controls. Although, this gene-panel could potentially discriminate OSCC tissues from absolute normal controls as solitarily diagnostic and/or predictive biomarkers, models generated also showed substantial discriminating efficacy. Eight-genes were found to be significantly associated with poor-prognosis on clinico-pathological association. Protein-expression confirmed overexpression of gene-panel and added advantage of being secretory-protein. Importantly, up-regulated genes in our study showed significant relation with immune-cells infiltration suggesting their contribution in immune-escape.

CONCLUSION

Thus, we propose that the 13 gene-panel could pave the way to effective and personalized clinical-management of OSCC in terms of diagnostic and prognostic measures and thereby as therapeutic targets.

Verification of the expression trend and interaction prediction of innate immune cells and immune-checkpoint molecules in the process of oral mucosal carcinogenesis

OBJECTIVES

This study aimed to explore the expression trends of innate immune cells and immune-checkpoint molecules validated by data calculation in the process of oral mucosal carcinogenesis, as well as to explore methods of suppressing oral mucosal carcinogenesis based on immunotherapy by predicting their interactions. Me-thods 1) The cancer genome atlas (TCGA) database comprehensively scores immune cells and immune-checkpoint molecules in the process of oral mucosal carcinogenesis and screens out intrinsic immune cells and immune-checkpoint molecules that interfere with tumor immune escape. 2) Clinical patient blood routine data were collected for the statistical analysis of peripheral blood immune cells during the progression of oral mucosal carcinogenesis. Immune cells in peripheral blood that may affect the progression of oral mucosal carcinogenesis were screened. 3) Immunohistochemical staining was performed on intrinsic immune cells and immune-checkpoint molecules validated based on data calculation in various stages of oral mucosal carcinogenesis. 4) Special staining was used to identify innate immune cells in various stages of oral mucosal carcinogenesis based on data-calculation verification. 5) Survival analysis was conducted on intrinsic immune cells and immune-checkpoint molecules validated based on data calculation during the process of oral mucosal carcinogenesis. The association of intrinsic immune cells and immune-checkpoint molecules with the prognosis of oral squamous cell carcinoma was verified.

RESULTS

The expression of monocytes and neutrophils increased during the process of oral mucosal carcinogenesis. The expression of eosinophils showed a single peak trend of up and down. The expression of mast cells decreased. In the process of oral mucosal carcinogenesis, the expression of the immune-checkpoint molecules cytotoxic T-lymphocyte-associated protein 4 (CTLA4) and programmed cell death-ligand (PD-L1) increased. The expression trends of monocytes, neutrophils, and eosinophils were positively correlated with those of CTLA4 and PD-L1 immune-checkpoint molecules. The expression trend of mast cells was negatively correlated with the expression of CTLA4 and PD-L1. Monocytes, neutrophils, and eosinophils may promote tumor immune escape mediated by CTLA4 and/or PD-L1, thereby accelerating the progression of oral mucosal carcinogenesis. Mast cells may inhibit tumor immune escape mediated by CTLA4 and/or PD-L1, delaying the progression of oral mucosal carcinogenesis.

CONCLUSIONS

Therefore, interference with specific immune cells in innate immunity can regulate the expression of CTLA4 and/or PD-L1 to a certain extent, inhibit tumor immune escape, and delay the progression of oral mucosal carcinogenesis.

Poor Dental Health as a Risk Factor for Alveolar Ridge Malignancies

OBJECTIVE

To determine the association between poor dental health and risk of oral cavity squamous cell cancer (OCSCC) at individual tumor subsites.

STUDY DESIGN

Case-control and cross-sectional METHODS: A case-control study was performed using a population-based cohort in North Carolina (Carolina Head and Neck Cancer Epidemiology Study [CHANCE]). A secondary cross-sectional analysis was performed with an institutional cohort (WashU/Siteman). Cases were adults with primary OCSCC and an identifiable tumor subsite. In the CHANCE cohort, controls were adults without head and neck cancer. In the Washington University/Siteman cohort, patients with tongue cancer served as the comparator group. We used number of missing teeth (categorized 0-6, 7-24, 25-28) as a surrogate for poor dental health, which was self-reported in CHANCE and measured on a pretreatment computed tomography scan in the WashU/Siteman study. Adjusted odds ratios (aORs) for missing teeth were estimated for each tumor subsite using binomial logistic regression models.

RESULTS

Near complete tooth loss (25-28 teeth) was associated with a 3.5-fold increased risk of alveolar ridge malignancy (aOR: 3.51; 95% confidence interval [CI]: 1.14-11.01, P = .03) in the CHANCE study. This association was confirmed in our cross-sectional analysis (WashU/Siteman study) where missing 25-28 teeth was associated with an increased risk of alveolar ridge compared to tongue cancer (aOR: 4.60; 95% CI: 1.97-11.10, P = .001).

CONCLUSIONS

This study suggests an association between poor dental health and risk of alveolar ridge cancer independent of smoking, alcohol use, age, race, and sex. Future prospective and translational studies are needed to confirm this association and elucidate the mechanism of dental disease in alveolar ridge malignancies.

Immunophenotypic and Gene Expression Analyses of the Inflammatory Microenvironment in High-Grade Oral Epithelial Dysplasia and Oral Lichen Planus

BACKGROUND

Oral lichen planus (OLP) and oral epithelial dysplasia (OED) present diagnostic challenges due to clinical and histologic overlap. This study explores the immune microenvironment in OED, hypothesizing that immune signatures could aid in diagnostic differentiation and predict malignant transformation.

METHODS

Tissue samples from OED and OLP cases were analyzed using immunofluorescence/immunohistochemistry (IF/IHC) for CD4, CD8, CD163/STAT1, and PD-1/PDL-1 expression. RNA-sequencing was performed on the samples, and data was subjected to CIBERSORTx analysis for immune cell composition. Gene Ontology analysis on the immune differentially expressed genes was also conducted.

RESULTS

In OED, CD8 + T-cells infiltrated dysplastic epithelium, correlating with dysplasia severity. CD4 + lymphocytes increased in the basal layer. STAT1/CD163 + macrophages correlated with CD4 + intraepithelial distribution. PD-1/PDL-1 expression varied. IF/IHC analysis revealed differential immune cell composition between OED and OLP. RNA-sequencing identified upregulated genes associated with cytotoxic response and immunosurveillance in OED. Downregulated genes were linked to signaling, immune cell recruitment, and tumor suppression.

CONCLUSIONS

The immune microenvironment distinguishes OED and OLP, suggesting diagnostic potential. Upregulated genes indicate cytotoxic immune response in OED. Downregulation of TRADD, CX3CL1, and ILI24 implies dysregulation in TNFR1 signaling, immune recruitment, and tumor suppression. This study contributes to the foundation for understanding immune interactions in OED and OLP, offering insights into future objective diagnostic avenues.

Depth of invasion of oral squamous cell carcinoma in Nos2-knockout mice correlated to alterations in systemic inflammatory markers following 4NQO treatment

BACKGROUND

Peripheral blood analysis is a non-invasive and low-cost technique of prognostic value for several diseases, including oral cancer. Considering the role of inducible nitric oxide synthase in tumor-associated inflammation, this study purposed to evaluate the influence of this enzyme on peripheral blood parameters and systemic inflammatory biomarkers during murine oral carcinogenesis.

METHODS

A 50 μg/mL solution of 4-nitroquinoleine-N-oxide was provided to 15 C57BL/6J (Nos2+/+ ) and 16 B6.129P2-Nos2tm1Lau /J (Nos2-/- ) for 16 weeks. Animals were followed for 8 weeks after treatment. Blood samples and tongues were collected for hematological and histopathological analyses. Red blood cells, white blood cells, and platelet cell parameters were analyzed. The neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and the systemic immune-inflammation index were also calculated. The depth of invasion of all carcinomas was measured.

RESULTS

Differences were found in several blood parameters. The depth of invasion in Nos2-/- was lower than in Nos2+/+ (p = 0.009), and strong correlations were found between depth of invasion and neutrophil count (ρ = -0.68, p = 0.017), lymphocyte count (ρ = 0.72, p = 0.011), neutrophil-to-lymphocyte ratio (ρ = -0.65, p = 0.025), platelet-to-lymphocyte ratio (ρ = -0.73, p = 0.013), and systemic immune-inflammation index (ρ = -0.67, p = 0.037) in Nos2-/- mice.

CONCLUSION

Inducible nitric oxide synthase seems to have an important role in OSCC invasion and progression, which might be associated to alterations in immune-inflammatory cell dynamics evidenced by peripheral blood and systemic inflammatory biomarkers.

An immune cell infiltration landscape classification to predict prognosis and immunotherapy effect in oral squamous cell carcinoma

Tumor immune cell infiltration (ICI) is associated with the prognosis of oral squamous cell carcinoma (OSCC) patients and the effect of immunotherapy. The combat algorithm was used to merge the data from three databases and the Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) algorithm to quantify the amount of infiltrated immune cells. Unsupervised consistent cluster analysis was used to determine ICI subtypes, and differentially expressed genes (DEGs) were determined according to these subtypes. The DEGs were then clustered again to obtain the ICI gene subtypes. The principal component analysis (PCA) and the Boruta algorithm were used to construct the ICI scores. Three different ICI clusters and gene clusters with a prognosis of significant difference were found and the ICI score was constructed. Patients with higher ICI scores have a better prognosis following internal and external verification. Besides, the proportion of patients with effective immunotherapy was higher than those with low scores in two external datasets with immunotherapy. This study shows that the ICI score is an effective prognostic biomarker and a predictor of immunotherapy.

Spatial subsetting enables integrative modeling of oral squamous cell carcinoma multiplex imaging data

Oral squamous cell carcinoma (OSCC), a prevalent and aggressive neoplasm, poses a significant challenge due to poor prognosis and limited prognostic biomarkers. Leveraging highly multiplexed imaging mass cytometry, we investigated the tumor immune microenvironment (TIME) in OSCC biopsies, characterizing immune cell distribution and signaling activity at the tumor-invasive front. Our spatial subsetting approach standardized cellular populations by tissue zone, improving feature reproducibility and revealing TIME patterns accompanying loss-of-differentiation. Employing a machine-learning pipeline combining reliable feature selection with multivariable modeling, we achieved accurate histological grade classification (AUC = 0.88). Three model features correlated with clinical outcomes in an independent cohort: granulocyte MAPKAPK2 signaling at the tumor front, stromal CD4+ memory T cell size, and the distance of fibroblasts from the tumor border. This study establishes a robust modeling framework for distilling complex imaging data, uncovering sentinel characteristics of the OSCC TIME to facilitate prognostic biomarkers discovery for recurrence risk stratification and immunomodulatory therapy development.

Real-Time PCR Detection of Candida Species in Biopsy Samples from Non-Smokers with Oral Dysplasia and Oral Squamous Cell Cancer: A Retrospective Archive Study

The impact of Candida sp. in the development of oral cancer remains uncertain and requires sensitive analytical approaches for clarification. Given the invasive capabilities of these microorganisms in penetrating and invading host tissues through hyphal invasion, this study sought to detect the presence of five Candida sp. in oral biopsy tissue samples from non-smoker patients. Samples were obtained from patients at varying stages of oral carcinogenesis, including dysplasia, carcinoma in situ, OSCC, and histologically benign lesions, and analyzed using Real-Time PCR. Oral tissue samples from 80 patients (46 males and 34 females) were included. Significantly higher C. albicans presence was detected in the mild/moderate dysplasia group compared to the healthy (p = 0.001), carcinoma in situ (p = 0.031) and OSCC groups (p = 0.000). Similarly, C. tropicalis carriage was higher in tissues with mild/moderate dysplasia compared to healthy (p = 0.004) and carcinoma in situ (p = 0.019). Our results showed a significant increase in the presence of C. albicans and C. tropicalis within the mild/moderate dysplasia group compared to other cohorts. Coexistence of these two microorganisms was observed, suggesting a potential transition from a commensal state to an opportunistic pathogen, which could be particularly linked to the onset of oral neoplasia.

Salivary Chemical Barrier Proteins in Oral Squamous Cell Carcinoma-Alterations in the Defense Mechanism of the Oral Cavity

Oral squamous cell carcinoma (OSCC) is one of the most frequent types of head and neck cancer. Despite the genetic and environmental risk factors, OSCC is also associated with microbial infections and/or dysbiosis. The secreted saliva serves as the chemical barrier of the oral cavity and, since OSCC can alter the protein composition of saliva, our aim was to analyze the effect of OSCC on the salivary chemical barrier proteins. Publicly available datasets regarding the analysis of salivary proteins from patients with OSCC and controls were collected and examined in order to identify differentially expressed chemical barrier proteins. Network analysis and gene ontology (GO) classification of the differentially expressed chemical barrier proteins were performed as well. One hundred and twenty-seven proteins showing different expression pattern between the OSCC and control groups were found. Protein-protein interaction networks of up- and down-regulated proteins were constructed and analyzed. The main hub proteins (IL-6, IL-1B, IL-8, TNF, APOA1, APOA2, APOB, APOC3, APOE, and HP) were identified and the enriched GO terms were examined. Our study highlighted the importance of the chemical barrier of saliva in the development of OSCC.

Intratumoral Microbiota Changes with Tumor Stage and Influences the Immune Signature of Oral Squamous Cell Carcinoma

Characterization of the oral microbiota profile through various studies has shown an association between the microbiome and oral cancer; however, stage-specific determinants of dynamic changes in microbial communities of oral cancer remain elusive. Additionally, the influence of the intratumoral microbiota on the intratumoral immune system remains largely unexplored. Therefore, this study aims to stratify microbial abundance in the early-onset and subsequent stages of oral cancer and analyze their influence on clinical-pathological and immunological features. The microbiome composition of tissue biopsy samples was identified using 16S rRNA amplicon sequencing, while intratumoral and systemic immune profiling was done with flow cytometry and immunohistochemistry-based analysis. The bacterial composition differed significantly among precancer, early cancer, and late cancer stages with the enrichment of genera Capnocytophaga, Fusobacterium, and Treponema in the cancer group, while Streptococcus and Rothia were enriched in the precancer group. Late cancer stages were significantly associated with Capnocytophaga with high predicting accuracy, while Fusobacterium was associated with early stages of cancer. A dense intermicrobial and microbiome-immune network was observed in the precancer group. At the cellular level, intratumoral immune cell infiltration of B cells and T cells (CD4+ and CD8+) was observed with enrichment of the effector memory phenotype. Naive and effector subsets of tumor-infiltrating lymphocytes (TILs) and related gene expression were found to be distinctly associated with bacterial communities; most importantly, highly abundant bacterial genera of the tumor microenvironment were either negatively correlated or not associated with the effector lymphocytes, which led to the conclusion that the tumor microenvironment favors an immunosuppressive and nonimmunogenic microbiota. IMPORTANCE The gut microbiome has been explored extensively for its importance in the modulation of systemic inflammation and immune response; in contrast, the intratumoral microbiome is less studied for its influence on immunity in cancer. Given the established correlation between intratumoral lymphocyte infiltration and patient survival in cases of solid tumors, it was pertinent to explore the extrinsic factor influencing immune cell infiltration in the tumor. Modulation of intratumoral microbiota could have a beneficial effect on the antitumor immune response. This study stratifies the microbial profile of oral squamous cell carcinoma starting from precancer to late-stage cancer and provides evidence for their immunomodulatory role in the tumor microenvironment. Our results suggest combining microbiome study with immunological signatures of tumors for their prognostic and diagnostic application.

The Role of IL-17 in the Pathogenesis of Oral Squamous Cell Carcinoma

Elucidating the inflammatory mechanisms underlying formation and progression of oral squamous cell carcinoma (OSCC) is crucial for discovering new targeted therapeutics. The proinflammatory cytokine IL-17 has proven roles in tumor formation, growth, and metastasis. The presence of IL-17 is demonstrated in both in vitro and in vivo models, and in OSCC patients, is mostly accompanied by enhanced proliferation and invasiveness of cancer cells. Here we review the known facts regarding the role of IL-17 in OSCC pathogenesis, namely the IL-17 mediated production of proinflammatory mediators that mobilize and activate myeloid cells with suppressive and proangiogenic activities and proliferative signals that directly induce proliferation of cancer cells and stem cells. The possibility of a potential IL-17 blockade in OSCC therapy is also discussed.

Identification of Potential Molecular Mechanisms and Prognostic Markers for Oral Squamous Cell Carcinoma: A Bioinformatics Analysis

Aims and Objectives

The goal of this study was to uncover crucial biochemical pathways, prognostic indicators, and therapeutic targets in patients with oral cancer in order to enhance therapy strategies.

Materials and Methods

Five gene expression omnibus datasets were analyzed by using bioinformatics approaches to identify differentially expressed genes (DEGs). To determine biological alterations, gene ontology (GO) and KEGG pathway analyses were implied using the identified DEGs. Hub genes were determined using protein-protein interaction (PPI) network analysis and an interactome was constructed using NetworkAnalyst. Furthermore, five hub genes were evaluated for use as prognostic markers by using the human protein atlas (HPA) and the GEPIA2.0 database. In addition, the correlations between hub-gene expression and immune cell infiltration of oral squamous cell carcinoma (OSCC) tumors were analyzed using the tWumor immune estimation resource (TIMER) database.

Results

A total of 2071 upregulated genes and 1893 downregulated genes were identified. GO and pathway analysis showed DEGs were enriched in multiple immune response terms and interaction of inflammatory cytokines. From the PPI network, five hub genes were identified that have a crucial role in OSCC. These included interferon regulatory factor 4 (IRF4), chemokine receptor 7 (CCR7), TNF receptor superfamily member 17 (TNFRSF17), CD27, and sphingosine-1-phosphate receptor 4 (S1PR4), which were predicted to be favorable prognostic markers for OSCC using HPA. Overall survival analysis revealed that low expression of the five hub genes was significantly associated with worse overall survival. Our analysis of tumor-associated immune infiltration revealed that increased IRF4 expression was positively correlated with the gene expression profiles suggestive of infiltration of all immune cell types, whereas increased CCR7 expression was negatively correlated with neutrophil infiltration. Increased expression of CD27, S1PR4, and TNFRSF17 was found to be negatively correlated with dendritic cell, M0 macrophage, and neutrophil infiltration.

Conclusion

In summary, inflammation, and the immune response play an important role in OSCC. All five hub genes were good predictors of OSCC prognosis, suggesting that they could be used as potential therapeutic targets and tumor markers.

Tumour Necrosis Factor Alpha (TNF-α) and Oral Squamous Cell Carcinoma

Uncovering the inflammatory mechanisms underpinning initiation, progression, and promotion of oral squamous cell carcinoma (OSCC) development is fundamental to the rational pursuit of targeted therapeutics. Here we present a review of the current knowledge of the role of TNF-α in the aetiology, pathogenesis, and potential therapies with regards to OSCC. TNF-α is worthy of particular attention in OSCC, with its presence demonstrated to enhance cell proliferation and its downregulation demonstrated to inhibit proliferation and migration in other carcinomas in both in vitro and in vivo models and oral cancer patients. Increased TNF-α in the OSCC tumour microenvironment has been demonstrated to favour invasion through promotion of firstly the pro-inflammatory, pro-invasive phenotypes of OSCC cells and secondly its paracrine mechanism mediating recruitment and activation of inflammatory cells. Polymorphisms affecting the gene expression of TNF-α have been strongly associated with an increased risk for oral squamous cell carcinoma. A number of studies have considered TNF-α within biofluids, including saliva and serum, as a potential biomarker for the early detection of OSCC, as well as its staging, differentiation, and prognosis. The broad and multifaceted role that TNF-α plays in many inflammatory states presents an obvious confounder, particularly with demonstrated increased TNF-α levels in common oral disease states. Lastly, biologic agents targeting TNF-α are currently in clinical use for immune-mediated inflammatory rheumatological and gastrointestinal diseases. There is the potential that these biological agents might have an adjunctive role in OSCC prevention and treatment.

CAR-T cells targeting HLA-G as potent therapeutic strategy for EGFR-mutated and overexpressed oral cancer

Oral squamous cell carcinoma (OSCC) is a common malignancy in the world. Recently, scientists have focused on therapeutic strategies to determine the regulation of tumors and design molecules for specific targets. Some studies have demonstrated the clinical significance of human leukocyte antigen G (HLA-G) in malignancy and NLR family pyrin domain-containing 3 (NLRP3) inflammasome in promoting tumorigenesis in OSCC. This is the first study to investigate whether aberrant epidermal growth factor receptor (EGFR) induces HLA-G expression through NLRP3 inflammasome-mediated IL-1β secretion in OSCC. Our results showed that the upregulation of NLRP3 inflammasome leads to abundant HLA-G in the cytoplasm and cell membrane of FaDu cells. In addition, we also generated anti-HLA-G chimeric antigen receptor (CAR)-T cells and provided evidence for their effects in EGFR-mutated and overexpressed oral cancer. Our results may be integrated with OSCC patient data to translate basic research into clinical significance and may lead to novel EGFR-aberrant OSCC treatment.

Differential Regulation of Innate Lymphoid Cells in Human and Murine Oral Squamous Cell Carcinoma

Oral squamous cell carcinomas (OSCC) remain a major healthcare burden in Asian countries. In Pakistan alone, it is the most common cancer in males and second only to breast cancer in females. Alarmingly, treatment options for OSCC remain limited. With this context, investigations made to explore the inflammatory milieu of OSCC become highly relevant, with the hope of practicing immunotherapeutic approaches to address this highly prevalent tumor. We investigated the newly identified innate lymphoid cells (ILCs) and associated cytokines in well-defined human oral squamous cell carcinoma (OSCC) as well as in a 7,12-dimethylbenz[a]anthracene (DMBA)-induced murine model of OSCC using flow cytometry and quantitative real-time polymerase chain reaction (qPCR). We further went on to explore molecular circuitry involved in OSCC by developing a murine model of OSCC and using an α-Thy1 antibody to inhibit ILCs. Amongst the ILCs that we found in human OSCC, ILC3 (23%) was the most abundant, followed by ILC2 (17%) and ILC1 (1%). Mice were divided into four groups: DMBA (n = 33), DMBA+antibody (Ab) (n = 30), acetone (n = 5), and control (n = 5). In murine OSCC tissues, ILC1 and ILC3 were down-infiltrated, while ILC2 remained unchanged compared to controls. Interestingly, compared to the controls (DMBA group), mice treated with the α-Thy1 antibody showed fewer numbers of large tumors, and a larger percentage of these mice were tumor-free at this study's end point. We present novel data on the differential expansion/downsizing of ILCs in OSCC, which provides a pivotal basis to dive deeper into molecular circuitry and the OSCC tumor niche to devise novel diagnostic, therapeutic, and prognostic strategies to prevent/treat oral cancers.

Effect of ethanol extract from Chrysanthemum cinerariifolium leaves on Ki-67 proliferation and dysplasia severity in a rat model of oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is a malignant tumor that can rapidly infiltrate the oral epithelial tissue and cause high mortality worldwide because the available therapies are less effective. Chrysanthemum cinerariifolium leaf contains secondary metabolites as anti-inflammatory, antioxidant, anticancer, and antimutagenic.

Aims

The study aimed to analyze the ethanolic extract of C. cinerariifolium leaf in reducing proliferation (Ki-67) and the degree of dysplasia in OSCC rats.

Methods

This study used male Sprague Dawley induced by 7,12-dimethylbenz(a)anthracene (DMBA) 0.5% and divided into five treatment groups, namely positive control/C+ (sick), negative control/C- (healthy), and treatment group induced with DMBA and given extract C. cinerariifolium leaf with successive doses of T1, T2, and T3 (50, 100, and 200 mg/kg bw). The oral epithelium was stained with hematoxylin and eosin and immunohistochemically stained with a Ki-67 monoclonal antibody. The statistical analysis utilizes the one-way analysis of variance test.

Results

The results showed that T1 at a dose of 200 mg/kg bw could significantly reduce Ki-67 expression and the degree of oral epithelial dysplasia (OED; p < 0.05) close to healthy controls.

Conclusion

The conclusion shows that C. cinerariifolium leaf extract can be a therapy against OSCC by decreasing cell proliferation and the degree of OED.

Risk of subsequent primary oral cancer in a cohort of 69,460 5-year survivors of childhood and adolescent cancer in Europe: the PanCareSurFup study

BACKGROUND

Survivors of childhood cancer are at risk of subsequent primary malignant neoplasms (SPNs), but the risk for rarer types of SPNs, such as oral cancer, is uncertain. Previous studies included few oral SPNs, hence large-scale cohorts are required to identify groups at risks.

METHODS

The PanCareSurFup cohort includes 69,460 5-year survivors of childhood cancer across Europe. Risks of oral SPNs were defined by standardised incidence ratios (SIRs), absolute excess risks and cumulative incidence.

RESULTS

One hundred and forty-five oral SPNs (64 salivary gland, 38 tongue, 20 pharynx, 2 lip, and 21 other) were ascertained among 143 survivors. Survivors were at 5-fold risk of an oral SPN (95% CI: 4.4-5.6). Survivors of leukaemia were at greatest risk (SIR = 19.2; 95% CI: 14.6-25.2) followed by bone sarcoma (SIR = 6.4, 95% CI: 3.7-11.0), Hodgkin lymphoma (SIR = 6.2, 95% CI: 3.9-9.9) and soft-tissue sarcoma (SIR = 5.0, 95% CI: 3.0-8.5). Survivors treated with radiotherapy were at 33-fold risk of salivary gland SPNs (95% CI: 25.3-44.5), particularly Hodgkin lymphoma (SIR = 66.2, 95% CI: 43.6-100.5) and leukaemia (SIR = 50.5, 95% CI: 36.1-70.7) survivors. Survivors treated with chemotherapy had a substantially increased risk of a tongue SPN (SIR = 15.9, 95% CI: 10.6-23.7).

CONCLUSIONS

Previous radiotherapy increases the risk of salivary gland SPNs considerably, while chemotherapy increases the risk of tongue SPNs substantially. Awareness of these risks among both health-care professionals and survivors could play a crucial role in detecting oral SPNs early.

Potential Histopathological and Immune Biomarkers in Malignant and Non-Malignant Oral Lesions

Objectives

The presented case-control study was developed to characterize the clinical, histopathological and immunological profile of patients with traumatic injuries, benign neoplasms, potentially malignant oral disorders and malignant neoplasms of the oral cavity, in order to identify biomarkers of malignancy.

Material and Methods

Clinical information was collected from dental records and several techniques were performed, including histopathological evaluation in sections stained with haematoxylin and eosin, immunohistochemistry for programmed death ligand-1 and measurement of serum levels of interferon-gamma, interleukin-6, -10 and -12. Statistical analysis was performed using IBM SPSS^® Statistics software.

Results

This study included 8 patients with traumatic injuries, 8 with benign neoplasms, 6 with potentially malignant oral disorders and 11 with malignant neoplasms. An association was observed between the classification of the lesion and smoking (P < 0.05), the size of the lesion (P < 0.05), the density of the inflammatory infiltrate (P < 0.001), the degree of dysplasia (P < 0.01) and programmed death ligand-1 expression (P < 0.01).

Conclusions

Therefore, it is suggested that smoking, the size of the lesion, the inflammatory infiltrate and the programmed death ligand-1 expression can be considered potential biomarkers of oral malignancy.

Immunology of Oral Squamous Cell Carcinoma-A Comprehensive Insight with Recent Concepts

This review aims to understand the concept of oral cancer immunology through the notion of immune profiling, immunoediting and immunotherapy, and to gain knowledge regarding its application for the management of oral cancer patients. Oral cancer is an immunogenic tumor where the cells of the tumor microenvironment play an important role in tumorigenesis. Understanding the mechanism of these modulations can help design immunotherapeutic strategies in oral cancer patients. This article gives an overview of immunomodulation in the oral cancer tumor microenvironment, with concepts of immune profiling, immunoediting and immunotherapy. English literature searches via Google Scholar, Web of Science, EBSCO, Scopus, and PubMed database were performed with the key words immunology, tumor microenvironment, cells, cross talk, immune profiling, biomarkers, inflammation, gene expression, techniques, immunoediting, immunosurveillance, tumor escape, immunotherapy, immune checkpoint inhibitors, vaccines in cancer, oral cancer, and head and neck cancer. Original research articles, reviews, and case reports published from 2016-2021 (n = 81) were included to appraise different topics, and were discussed under the following subsections. Literature published on oral cancer immunology reveals that oral cancer immune profiling with appropriate markers and techniques and knowledge on immunoediting concepts can help design and play an effective role in immunotherapeutic management of oral cancer patients. An evaluation of oral cancer immunology helps to determine its role in tumorigenesis, and immunotherapy could be the emerging drift in the effective management of oral cancer.

Prognostic Value of Neutrophil Percentage-to-Albumin Ratio in Patients with Oral Cavity Cancer

This study investigated preoperative neutrophil percentage-to-albumin ratio (NPAR) for predicting oral cavity squamous cell carcinoma (OSCC) survival. We retrospectively analyzed 368 patients who received curative OSCC surgery between 2008 and 2017. Receiver operating characteristic curve analyses were employed to identify the optimal NPAR cutoff (16.93), and the patients were then separated into low-NPAR and high-NPAR groups. Intergroup differences in survival were determined through Kaplan−Meier analysis and log-rank tests. Disease-free survival (DFS) and overall survival (OS) predictors were identified using Cox proportional-hazards models. A nomogram integrating independent prognostic factors was proposed to increase the accuracy of OS prediction. A high NPAR (≥16.93) was associated with worse median OS and DFS than was a low NPAR (both p < 0.001); this finding was confirmed through multivariate analyses (hazard ratio (HR) for OS = 2.697, p < 0.001; and HR for DFS = 1.671, p = 0.008). The nomogram’s favorable predictive ability was confirmed by the calibration plots and concordance index (0.784). The preoperative NPAR is thus a promising prognostic biomarker in patients with OSCC after external validation in a larger cohort. Our nomogram can facilitate clinical use of the NPAR and provides accurate individualized OS predictions.

The Assessment of Serum Cytokines in Oral Squamous Cell Carcinoma Patients: An Observational Prospective Controlled Study

Background: The oral squamous cell carcinoma (OSCC) tumor microenvironment (TME) is a complex interweb of cells and mediators balancing carcinogenesis, inflammation, and the immune response. However, cytokines are not only secreted within the TME but also released by a variety of other cells that do not comprise the TME; therefore, a thorough assessment of humoral changes in OSCC should include the measurement of serum cytokines. Methods: We assessed the role of various serum cytokines in the evolution of OSCC, before and after treatment, versus a control group. We measured the serum concentrations of MIP-1α, IL-1β, IL-4, IL-6, IL-8, IL-10, and TNF-α. Results: Significantly higher values (p < 0.01) were noted for IL-1β, IL-6, IL-8, IL-10, and TNF-α in the OSCC group before treatment (n = 13) compared with the control group (n = 14), and the increased concentrations persisted after treatment (n = 11). Furthermore, the variations in the values of MIP-1α, IL-1β, IL-10, and TNF-α are correlated both before and after treatment (p < 0.01). In the pretherapeutic group, IL-6 and IL-8 concentrations also correlate with IL-1β and IL-10 serum levels (p < 0.01), while in the posttherapeutic group, IL-4 varies with MIP-1α and TNF-α (p < 0.01). Conclusion: In OSCC patients, serum cytokine levels are significantly higher compared with control, but they are not significantly altered by treatment, therefore implying that they are also influenced by systemic factors. The interactions between all involved cytokines and the various pathways they regulate warrant further studies to clarify their definitive roles.

Transcriptional analysis highlights three distinct immune profiles of high-risk oral epithelial dysplasia

Oral potentially malignant disorders (OPMD) are precursors of oral squamous cell carcinoma (OSCC), and the presence of oral epithelial dysplasia (OED) in OPMD confers an increased risk of malignant transformation. Emerging evidence has indicated a role for the immune system in OPMD disease progression; however, the underlying immune mechanisms remain elusive. In this study, we used immune signatures established from cancer to delineate the immune profiles of moderate and severe OED, which are considered high-risk OPMD. We demonstrated that moderate and severe OEDs exhibit high lymphocyte infiltration and upregulation of genes involved in both immune surveillance (major histocompatibility complex-I, T cells, B cells and cytolytic activity) and immune suppression (immune checkpoints, T regulatory cells, and tumor-associated macrophages). Notably, we identified three distinct subtypes of moderate and severe OED: immune cytotoxic, non-cytotoxic and non-immune reactive. Active immune surveillance is present in the immune cytotoxic subtype, whereas the non-cytotoxic subtype lacks CD8 immune cytotoxic response. The non-immune reactive subtype showed upregulation of genes involved in the stromal microenvironment and cell cycle. The lack of T cell infiltration and activation in the non-immune reactive subtype is due to the dysregulation of CTNNB1, PTEN and JAK2. This work suggests that moderate and severe OED that harbor the non-cytotoxic or non-immune reactive subtype are likely to progress to cancer. Overall, we showed that distinct immune responses are present in high-risk OPMD, and revealed targetable pathways that could lead to potential new approaches for non-surgical management of OED.

Inflammation and Invasion in Oral Squamous Cell Carcinoma Cells Exposed to Electronic Cigarette Vapor Extract

Electronic cigarettes (eCig) represent a new avenue of tobacco exposure that involves heating oil-based liquids and the delivery of aerosolized flavors with or without nicotine, yet little is known about their overall health impact. The oral cavity is an anatomic gateway for exposure that can be compromised by activating myriad of signaling networks. Oral squamous cell carcinoma (OSSC) is a common malignancy affecting 30,000 people in the United States each year. Our objective was to determine the impact of eCig and nicotine on gingival OSSC invasion and their secretion of pro-inflammatory molecules. Gingiva-derived Ca9-22 cells and tongue-derived Cal27 cells were exposed to eCig vapor extract (EVE) generated from Red Hot or Green Apple (Apple) flavored eCig solution +/- nicotine for 6 hours. Isolation of protein lysates and collection conditioned media was done after treatment. Real-time cellular invasion was assessed using a RTCA DP instrument. Protein expression was determined using western blot. Compared to controls, we observed: elevated NF-kB, TNF-α, ERK, JNK, MMP-13 and cell invasion by Ca9-22 treated with Apple EVE; increased TNF-α and JNK by Ca9-22 treated with Red Hot EVE; and increased TNF-α and JNK by Cal27 cells treated with both Apple and Red Hot EVE. We conclude that eCig flavoring and nicotine orchestrated differential cell invasion and inflammatory effects. This study provides an important initial step in dissecting mechanisms of cancerous invasion and molecular avenues employed by OSCC.

Digesting the Role of JAK-STAT and Cytokine Signaling in Oral and Gastric Cancers

When small proteins such as cytokines bind to their associated receptors on the plasma membrane, they can activate multiple internal signaling cascades allowing information from one cell to affect another. Frequently the signaling cascade leads to a change in gene expression that can affect cell functions such as proliferation, differentiation and homeostasis. The Janus kinase-signal transducer and activator of transcription (JAK-STAT) and the tumor necrosis factor receptor (TNFR) are the pivotal mechanisms employed for such communication. When deregulated, the JAK-STAT and the TNF receptor signaling pathways can induce chronic inflammatory phenotypes by promoting more cytokine production. Furthermore, these signaling pathways can promote replication, survival and metastasis of cancer cells. This review will summarize the essentials of the JAK/STAT and TNF signaling pathways and their regulation and the molecular mechanisms that lead to the dysregulation of the JAK-STAT pathway. The consequences of dysregulation, as ascertained from founding work in haematopoietic malignancies to more recent research in solid oral-gastrointestinal cancers, will also be discussed. Finally, this review will highlight the development and future of therapeutic applications which modulate the JAK-STAT or the TNF signaling pathways in cancers.

Regulation of Carcinogenesis by Sensory Neurons and Neuromediators

Simple Summary

Sensory nerve fibers extensively innervate the entire body. They are the first to sense danger signals, including the ones coming from newly formed cancer cells. Various studies have demonstrated that the inactivation of sensory nerve fibers as well as the vagus nerve enhances tumor growth and spread in models including breast, pancreatic, and gastric cancer. On the other hand, there are also contradictory findings that show the opposite, namely that the inactivation of nerve fibers inhibits tumor growth. These discrepancies are likely caused by the stage and the level of aggressiveness of the tumor model used. Hence, further studies are required to determine the factors involved in neuro-immunological mechanisms of tumor growth and spread.

Abstract

Interactions between the immune system and the nervous system are crucial in maintaining homeostasis, and disturbances of these neuro-immune interactions may participate in carcinogenesis and metastasis. Nerve endings have been identified within solid tumors in humans and experimental animals. Although the involvement of the efferent sympathetic and parasympathetic innervation in carcinogenesis has been extensively investigated, the role of the afferent sensory neurons and the neuropeptides in tumor development, growth, and progression is recently appreciated. Similarly, current findings point to the significant role of Schwann cells as part of neuro-immune interactions. Hence, in this review, we mainly focus on local and systemic effects of sensory nerve activity as well as Schwann cells in carcinogenesis and metastasis. Specific denervation of vagal sensory nerve fibers, or vagotomy, in animal models, has been reported to markedly increase lung metastases of breast carcinoma as well as pancreatic and gastric tumor growth, with the formation of liver metastases demonstrating the protective role of vagal sensory fibers against cancer. Clinical studies have revealed that patients with gastric ulcers who have undergone a vagotomy have a greater risk of stomach, colorectal, biliary tract, and lung cancers. Protective effects of vagal activity have also been documented by epidemiological studies demonstrating that high vagal activity predicts longer survival rates in patients with colon, non-small cell lung, prostate, and breast cancers. However, several studies have reported that inhibition of sensory neuronal activity reduces the development of solid tumors, including prostate, gastric, pancreatic, head and neck, cervical, ovarian, and skin cancers. These contradictory findings are likely to be due to the post-nerve injury-induced activation of systemic sensory fibers, the level of aggressiveness of the tumor model used, and the local heterogeneity of sensory fibers. As the aggressiveness of the tumor model and the level of the inflammatory response increase, the protective role of sensory nerve fibers is apparent and might be mostly due to systemic alterations in the neuro-immune response. Hence, more insights into inductive and permissive mechanisms, such as systemic, cellular neuro-immunological mechanisms of carcinogenesis and metastasis formation, are needed to understand the role of sensory neurons in tumor growth and spread.

Genetic Changes Driving Immunosuppressive Microenvironments in Oral Premalignancy

Oral premalignant lesions (OPLs) are the precursors to oral cavity cancers, and have variable rates of progression to invasive disease. As an intermediate state, OPLs have acquired a subset of the genomic alterations while arising in an oral inflammatory environment. These specific genomic changes may facilitate the transition to an immune microenvironment that permits malignant transformation. Here, we will discuss mechanisms by which OPLs develop an immunosuppressive microenvironment that facilitates progression to invasive cancer. We will describe how genomic alterations and immune microenvironmental changes co-evolve and cooperate to promote OSCC progression. Finally, we will describe how these immune microenvironmental changes provide specific and unique evolutionary vulnerabilities for targeted therapies. Therefore, understanding the genomic changes that drive immunosuppressive microenvironments may eventually translate into novel biomarker and/or therapeutic approaches to limit the progression of OPLs to potential lethal oral cancers.

Characterization of Oral Squamous Cell Carcinoma Associated Inflammation: A Pilot Study

Background: Oral squamous cell carcinoma (OSCC) is a devastating disease that is usually associated with a dense associated inflammatory infiltrate. Characterizing tumor-associated inflammation is critical to understand the pathogenies of tumor development and progression.

Methods: We have tested a protocol to analyze tissue and salivary immune cells and mediators of 37 patients with OSCC at different stages and compared to eight chronic periodontitis patients and 24 healthy controls. Tissue analysis was based on fluorescent immunohistochemistry (FIHC) and inflammatory mediators were analyzed using a Luminex-based 30-Plex panel. Immune cells were analyzed using multichannel flow cytometry including CD45, CD66b, CD3, CD4, CD8, CD25, CD56, CD68, CD138, PD-1, and PD-L1.

Results: We show an increase in OSCC-associated inflammation characterized by increased pro-inflammatory cytokines including IL-6, IL-8, TNFα, and GMCSF and increased salivary immune cells.

Conclusion: We described a new method to analyze salivary inflammatory markers that can be used in future studies to monitor disease progression and prognosis.

Inflammatory Mediators in Oral Cancer: Pathogenic Mechanisms and Diagnostic Potential

Approximately 15% of cancers are attributable to the inflammatory process, and growing evidence supports an association between oral squamous cell carcinoma (OSCC) and chronic inflammation. Different oral inflammatory conditions, such as oral lichen planus (OLP), submucous fibrosis, and oral discoid lupus, are all predisposing for the development of OSCC. The microenvironment of these conditions contains various transcription factors and inflammatory mediators with the ability to induce proliferation, epithelial-to-mesenchymal transition (EMT), and invasion of genetically predisposed lesions, thereby promoting tumor development. In this review, we will focus on the main inflammatory molecules and transcription factors activated in OSCC, with emphasis on their translational potential.

A Novel Autophagy-Related Prognostic Risk Model and a Nomogram for Survival Prediction of Oral Cancer Patients

Background. This study is aimed at constructing a risk signature to predict survival outcomes of ORCA patients. Methods. We identified differentially expressed autophagy-related genes (DEARGs) based on the RNA sequencing data in the TCGA database; then, four independent survival-related ARGs were identified to construct an autophagy-associated signature for survival prediction of ORCA patients. The validity and robustness of the prognostic model were validated by clinicopathological data and survival data. Subsequently, four independent prognostic DEARGs that composed the model were evaluated individually. Results. The expressions of 232 autophagy-related genes (ARGs) in 127 ORCA and 13 control tissues were compared, and 36 DEARGs were filtered out. We performed functional enrichment analysis and constructed protein–protein interaction network for 36 DEARGs. Univariate and multivariate Cox regression analyses were adopted for searching prognostic ARGs, and an autophagy-associated signature for ORCA patients was constructed. Eventually, 4 desirable independent survival-related ARGs (WDR45, MAPK9, VEGFA, and ATIC) were confirmed and comprised the prognostic model. We made use of multiple ways to verify the accuracy of the novel autophagy-related signature for survival evaluation, such as receiver-operator characteristic curve, Kaplan–Meier plotter, and clinicopathological correlational analyses. Four independent prognostic DEARGs that formed the model were also associated with the prognosis of ORCA patients. Conclusions. The autophagy-related risk model can evaluate OS for ORCA patients independently since it is accurate and stable. Four prognostic ARGs that composed the model can be studied deeply for target treatment.

αTAT1-induced tubulin acetylation promotes ameloblastoma migration and invasion

Ameloblastoma (AB) is the most common benign epithelial odontogenic tumor occurring in the jawbone. AB is a slowly growing tumor but sometimes shows a locally invasive and an aggressive growth pattern with a marked bone resorption. In addition, the local recurrence and distant metastasis of AB also sometimes occurs, which resembles one of the typical malignant potentials. From these points of view, to understand better the mechanisms of AB cell migration or invasion is necessary for the better clinical therapy and improvements of the patients' quality of life. Microtubules in eukaryotic cells reveal the shape of hollow cylinders made up of polymerized alpha (α)- and beta (β)-tubulin dimers and form the cytoskeleton together with microfilaments and intermediate filaments. Microtubules play important roles in cell migration by undergoing assembly and disassembly with post-translational modifications. Stability of microtubules caused by their acetylation is involved in cell migration. In this study, we investigated the expression and distribution of acetylated α-tubulin and alpha-tubulin N-acetyltransferase 1 (αTAT1), an enzyme which acetylates Lys-40 in α-tubulin, in AB specimens, and analyzed how tubulin was acetylated by αTAT1 activation in a human AB cell line, AM-1. Finally, we clarified that TGF-β-activated kinase1 (TAK1) was phosphorylated by TGF-β stimulation, then, induced tubulin acetylation via αTAT1 activation, which subsequently activated the migration and invasion of AB cells.

Effects of Red Blood Cell Transfusions on Distant Metastases of Oral Squamous Cell Carcinomas

Simple Summary

Patients with distant metastasis of oral squamous cell carcinoma should be identified at an early stage of disease. In this study, we investigated if patients who received red blood cell transfusions are at risk for the development of distant metastasis. A positive correlation was found between RBC transfusion (HR = 2.42) and the occurrence of M+ in a multivariate regression model. Therefore, the administration of RBC can be considered as an independent prognostic factor and special attention should be paid to its detrimental effects in the perioperative management of OSCC patients.

Abstract

There is no consensus on the effect of red blood cell (RBC) transfusions on patients with oral squamous cell carcinoma (OSCC). The aim of this study was to investigate the association between RBC administration and the occurrence of distant metastases (M+) after surgical treatment of OSCC. All medical records of patients who underwent primary surgery for OSCC in our department (2003–2019) were analyzed retrospectively (n = 609). Chi and Cox regression models were used to analyze the influence of transfusion on the development of M+, and survival rates. Kaplan–Meier curves were used for graphical presentation. A multitude of patient-specific factors showed a statistical impact in univariate analysis (transfusion, age, gender, diabetes, pT, pN, L, V, Pn, G, UICC, adjuvant therapy, free microvascular transplant, preoperative hemoglobin level). Transfusion status and pN stage were the only variables that showed a significant correlation to M+ in the multivariate Cox model. The hazard ratios for the occurrence of M+ were 2.42 for RBC transfusions and 2.99 for pN+. Administration of RBC transfusions was identified as a significant prognostic parameter for the occurrence of distant metastases after surgical treatment of OSCC. Hence, the administration of RBC transfusions should be considered carefully in the perioperative management.

The application value of contrast-enhanced computed tomography in cervical lymph node metastasis of oral carcinomas: A protocol for systematic review and meta-analysis

BACKGROUND

Oral carcinomas is a concerning condition around the world. Globally, it is the 11th most common form of cancer. Over 90% of oral carcinomas are squamous cell carcinomas. Smoking, tobacco intake, smokeless tobacco (snuff or chewing tobacco), excessive sunlight exposure, alcohol, betel nut consumption, human papillomavirus, and reverse end smoking are the most common causes of oral carcinomas. Oral carcinomas are prone to neck lymph mode metastasis, which has an impact on the prognosis of patients and the five-year survival rate. Thus, precise lymph node metastasis and staging of oral carcinomas are critical. With the development of nuclear medicine and molecular imaging, an increasing number of studies have found that Contrast-Enhanced Computed Tomography (CECT) has high diagnostic value for tumors.

METHODS AND ANALYSES

The reviewers will conduct a thorough search for related literature in 6 online databases, including The Cochrane Library, PubMed, WanFang database, Web of Science, Chinese biomedical literature database, and the China National Knowledge Infrastructure. The authors will obtain full text of studies deemed to be eligible to extract and synthesize data. The present systematic review will be reported in accordance with the Preferred Reporting Project (PRISMA-P) of the 2015 System Review and Meta-Analysis Protocol.

RESULTS

The present systematic analysis will pool the results of individual studies to assess the value of CECT in cervical lymph node metastasis of oral carcinomas.

CONCLUSION

The results in the proposed research will determine whether CECT is an efficient diagnostic method for cervical lymph node metastasis of oral carcinomas.

ETHICS AND DISSEMINATION

This study will utilize secondary data from pre-published studies. Therefore, an ethical clearance is not required. The research outcomes shall be disseminated in conference reports and peer-reviewed publications.

OSF REGISTRATION NUMBER

Oct 13, 2021.osf.io/k5nr9. (https://osf.io/k5nr9/).

TNFα Signaling Is Increased in Progressing Oral Potentially Malignant Disorders and Regulates Malignant Transformation in an Oral Carcinogenesis Model

Oral carcinogenesis represents a multi-stage process which encompasses several genetic and molecular changes that promote the progression of oral potentially malignant disorders (OPMDs) to oral squamous cell carcinomas (OSCCs). A better understanding of critical pathways governing the progression of OMPDs to OSCCs is critical to improve oncologic outcomes in the future. Previous studies have identified an important role of tumor necrosis factor α (TNFα) and TNF receptor 1 (TNFR1) in the invasiveness of oral cancer cell lines. Here, we investigate the expression of TNFα and TNFR1 in human OPMDs that progress to OSCC compared to non-progressing OPMDs utilizing fluorescent immunohistochemistry (FIHC) to show increased TNFα/TNFR1 expression in progressing OPMDs. In order to interrogate the TNFα/TNFR1 signaling pathway, we utilized a 4-nitroquinoline 1-oxide (4-NQO) mouse model of oral carcinogenesis to demonstrate that TNFα/TNFR1 expression is upregulated in 4-NQO-induced OSCCs. TNFα neutralization decreased serum cytokines, inhibited the development of invasive lesions and reduced tumor-associated neutrophils in vivo. Combined, this data supports the role of TNFα in oral malignant transformation, suggesting that critical immunoregulatory events occur downstream of TNFR1 leading to malignant transformation. Our results advance the understanding of the mechanisms governing OSCC invasion and may serve as a basis for alternative diagnostic and therapeutic approaches to OPMDs and OSCC management.

IL-1/IL-1R Signaling in Head and Neck Cancer

Decades ago, the study of cancer biology was mainly focused on the tumor itself, paying little attention to the tumor microenvironment (TME). Currently, it is well recognized that the TME plays a vital role in cancer development and progression, with emerging treatment strategies focusing on different components of the TME, including tumoral cells, blood vessels, fibroblasts, senescent cells, inflammatory cells, inflammatory factors, among others. There is a well-accepted relationship between chronic inflammation and cancer development. Interleukin-1 (IL-1), a potent pro-inflammatory cytokine commonly found at tumor sites, is considered one of the most important inflammatory factors in cancer, and has been related with carcinogenesis, tumor growth and metastasis. Increasing evidence has linked development of head and neck squamous cell carcinoma (HNSCC) with chronic inflammation, and particularly, with IL-1 signaling. This review focuses on the most important members of the IL-1 family, with emphasis on how their aberrant expression can promote HNSCC development and metastasis, highlighting possible clinical applications.

Salivary Cytokines as Biomarkers for Oral Squamous Cell Carcinoma: A Systematic Review

The prognosis of patients with oral squamous carcinoma (OSCC) largely depends on the stage at diagnosis, the 5-year survival rate being approximately 30% for advanced tumors. Early diagnosis, including the detection of lesions at risk for malignant transformation, is crucial for limiting the need for extensive surgery and for improving disease-free survival. Saliva has gained popularity as a readily available source of biomarkers (including cytokines) useful for diagnosing specific oral and systemic conditions. Particularly, the close interaction between oral dysplastic/neoplastic cells and saliva makes such fluid an ideal candidate for the development of non-invasive and highly accurate diagnostic tests. The present review has been designed to answer the question: "Is there evidence to support the role of specific salivary cytokines in the diagnosis of OSCC?" We retrieved 27 observational studies satisfying the inclusion and exclusion criteria. Among the most frequent cytokines investigated as candidates for OSCC biomarkers, IL-6, IL-8, TNF-α are present at higher concentration in the saliva of OSCC patients than in healthy controls and may therefore serve as basis for the development of rapid tests for early diagnosis of oral cancer.

Comparative sera proteomics analysis of differentially expressed proteins in oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) has increased in incidence from 1990 to 2017, especially in South and Southeast Asia. It is often diagnosed at an advanced stage with a poor prognosis. Therefore, early detection of OSCC is essential to improve the prognosis of OSCC. This study aims to identify the differentially expressed serum proteins as potential biomarkers for oral squamous cell carcinoma (OSCC).

Methods

Comparative proteomics profiling of serum samples from OSCC patients, oral potentially malignant disorder (OPMD) patients, and healthy individuals were performed using two-dimensional gel electrophoresis (2-DE) coupled with mass spectrometry (MS) (n = 60) and bioinformatics analysis. The enzyme-linked immunosorbent assay (ELISA) (n = 120) and immunohistochemistry (IHC) (n = 70) were used to confirm our findings.

Results

The 2-DE analysis revealed that 20 differentially expressed proteins were detected in OPMD and OSCC (p < 0.05). Bioinformatics analysis indicated that the activation of classical complement, liver X receptor/retinoid X receptor (LXR/RXR) activation, and acute phase response signaling pathway are associated with the development and progression of OSCC. Most of the detected proteins are acute-phase proteins and were related to inflammation and immune responses, including apolipoprotein A-I (APOA1), complement C3 (C3), clusterin (CLU), and haptoglobin (HP). The expression levels of CLU and HP in ELISA are consistent with the findings from the 2-DE analysis, except for the mean serum level of HP in OPMD, whereby it was slightly higher than that in control. IHC results demonstrated that CLU and HP are significantly decreased in OSCC tissues.

Conclusion

Decreased expression of CLU and HP could serve as complementary biomarkers of OSCC. These proteins may assist in predicting the outcomes of OSCC patients. However, a larger cohort is needed for further investigation.

Nano formulated Resveratrol inhibits metastasis and angiogenesis by reducing inflammatory cytokines in oral cancer cells by targeting tumor associated macrophages

Tumor associated macrophages in the tumor microenvironment secrete multiple cytokines, which regulate cancer cells growth and invasiveness. We systematically studied the role of cytokines in the induction of cancer stem like cells (CSCs) in oral cancer cells niche and evaluated the mechanism of Resveratrol nanoparticle (Res-Nano) mediated-reduction of CSCs properties in cells. A highly M1-like macrophages-enriched conditioned medium (CM) was generated by treating fixed doses of PMA and LPS in THP-1 cells alone as well as co-cultured of H-357 plus THP-1 cells. These M1-like macrophages increased the production of cytokines (e.g., TNF-α, IL-6, IL-1β, etc.). A CSCs populated environment was created after addition of cytokine-enriched-CM of co-culture of H-357 and THP-1 cells to cancer cells and cytokine enriched CM of THP-1 cells to patient derived primary oral cancer cells, respectively. After incubation with CM, enhancement of stemness, angiogenic and metastatic properties of both H-357 and primary oral cancer cells were noted. Res-NP decreased the cytokines level in CSCs-enriched cells and reduced the invasion, proliferation and growth of CSCs. Representative metastatic (CD133, ALDH1, CXCR4, etc.) and angiogenic markers (MMPs, iNOS, VEGF-A, etc.) were decreased after Res-NP treatment in CSCs enriched oral cancer cells niche. It also disrupted angiogenesis, depleted nitric oxide production in fertilized chick embryos and reduced the expression of metastatic and angiogenic markers in xenograft mice model system. Thus, this study concluded that CSCs-mediated stemness is a cytokine dependent phenomena and treatment of Res-NP inhibit this process in in vitro, in vivo and ex vivo systems.

The Response of the Tongue Epithelial on Cigarette Smoke Exposure as a Risk Factor for Oral Cancer Development

OBJECTIVE

 The aim of this study is to analyze the tongue epithelial response to cigarette smoke exposure on a number of macrophages, lymphocytes, plasma cells, and matrix metalloproteinase 9 (MMP-9) expression to determine the risk factor of oral cancer development.

MATERIALS AND METHODS

 Thirty Rattus norvegicus will be exposed to two kinds of cigarette smoke by a smoking pump for 4 and 8 weeks. The tongues were collected to analyze the number of macrophages, lymphocytes, and plasma cells with hematoxylin-eosin. The MMP-9 expression was similarly analyzed with immunohistochemical staining and then compared with the control group.

RESULTS

 The number of macrophages, lymphocytes, and MMP-9 expression was higher in the 8-week cigarette smoke exposure compared to the 4-week cigarette smoke exposure and the control group (p < 0.000). The number of plasma cell did not differ in the 8-week cigarette smoke exposure from that of the control group (p > 0.05). The number of plasma cells in the tongue tissue during the 4-week cigarette smoke exposure was not determined.

CONCLUSION

 Cigarette smoke exposure induces the risk of oral cancer development as a result of an increase in the number of macrophages, lymphocytes, and MMP-9 expression in the tongue epithelial.

Proteomic and phosphoproteomic profiling of shammah induced signaling in oral keratinocytes

Shammah is a smokeless tobacco product often mixed with lime, ash, black pepper and flavorings. Exposure to shammah has been linked with dental diseases and oral squamous cell carcinoma. There is limited literature on the prevalence of shammah and its role in pathobiology of oral cancer. In this study, we developed a cellular model to understand the effect of chronic shammah exposure on oral keratinocytes. Chronic exposure to shammah resulted in increased proliferation and invasiveness of non-transformed oral keratinocytes. Quantitative proteomics of shammah treated cells compared to untreated cells led to quantification of 4712 proteins of which 402 were found to be significantly altered. In addition, phosphoproteomics analysis of shammah treated cells compared to untreated revealed hyperphosphorylation of 36 proteins and hypophosphorylation of 83 proteins (twofold, p-value ≤ 0.05). Bioinformatics analysis of significantly altered proteins showed enrichment of proteins involved in extracellular matrix interactions, necroptosis and peroxisome mediated fatty acid oxidation. Kinase-Substrate Enrichment Analysis showed significant increase in activity of kinases such as ROCK1, RAF1, PRKCE and HIPK2 in shammah treated cells. These results provide better understanding of how shammah transforms non-neoplastic cells and warrants additional studies that may assist in improved early diagnosis and treatment of shammah induced oral cancer.

Key proteins of invadopodia are overexpressed in oral squamous cell carcinoma suggesting an important role of MT1-MMP in the tumoral progression

BACKGROUND

Oral squamous cell carcinoma (OSCC) is the most relevant malignant neoplasm among all head and neck tumours due to its high prevalence and unfavourable prognosis. Tumour invasion and metastasis that affect prognosis are result of a set of complex events that cells with invasive potential use to spread to other regions. These cells use several mechanisms to invade tissues, including a type of finger-like membrane protrusion called invadopodia. This study aims to investigate the immunoexpression of invaopodia related-proteins TKs5, cortactin, TKs4 and MT1-MMP in OSCC and correlate it to clinicopathological data.

METHODS

An immunohistochemical evaluation of fifty cases of OSCCs and 20 cases of oral mucosa (OM) were assessed. The expression of invadopodia proteins were analysed in comparison to normal tissue (OM) and correlated to different clinical-stage and histological grade of OSCC.

RESULTS

TKs5, cortactin, TKs4 and MT1-MMP were significantly overexpressed in OSCC when compared to OM (p < 0.0001). Among tumour stages, TKs5 showed a statistical difference in immunolabelling between stage I and III (p = 0.026). Cortactin immunolabelling was statistically higher in grade I than in grade II and III. No differences were seen on TKs4 expression based on tumour staging or grading. MT1-MMP was higher expressed and showed statistical difference between stages I and III and grades I compared to II and III.

CONCLUSIONS

The invadopodia related-proteins were found to be overexpressed in OSCC when compared to OM, suggesting invadopodia formation and activity. Besides overexpressed in OSCC, cortactin, TKs4 and TKs5 showed no or ambiguous differences in protein expression when compared among clinical-stages or histological grades groups. Conversely, the expression of MT1-MMP increased in advanced stages and less differentiated tumours, suggesting MT1-MMP expression as a promising prognostic marker in OSCC.

The role of icIL-1RA in keratinocyte senescence and development of the senescence-associated secretory phenotype

There is compelling evidence that senescent cells, through the senescence-associated secretory phenotype (SASP), can promote malignant transformation and invasion. Interleukin-1 (IL-1) is a key mediator of this cytokine network, but the control of its activity in the senescence programme has not been elucidated. IL-1 signalling is regulated by IL-1RA, which has four variants. Here, we show that expression of intracellular IL-1RA type 1 (icIL-1RA1), which competitively inhibits binding of IL-1 to its receptor, is progressively lost during oral carcinogenesis ex vivo and that the pattern of expression is associated with keratinocyte replicative fate in vitro We demonstrate that icIL-1RA1 is an important regulator of the SASP in mortal cells, as CRISPR/Cas9-mediated icIL-1RA1 knockdown in normal and mortal dysplastic oral keratinocytes is followed by increased IL-6 and IL-8 secretion, and rapid senescence following release from RhoA-activated kinase inhibition. Thus, we suggest that downregulation of icIL-1RA1 in early stages of the carcinogenesis process can enable the development of a premature and deregulated SASP, creating a pro-inflammatory state in which cancer is more likely to arise.

TNFα promotes oral cancer growth, pain, and Schwann cell activation

Oral cancer is very painful and impairs a patient's ability to eat, talk, and drink. Mediators secreted from oral cancer can excite and sensitize sensory neurons inducing pain. Cancer mediators can also activate Schwann cells, the peripheral glia that regulates neuronal function and repair. The contribution of Schwann cells to oral cancer pain is unclear. We hypothesize that the oral cancer mediator TNFα activates Schwann cells, which further promotes cancer progression and pain. We demonstrate that TNFα is overexpressed in human oral cancer tissues and correlates with increased self-reported pain in patients. Antagonizing TNFα reduces oral cancer proliferation, cytokine production, and nociception in mice with oral cancer. Oral cancer or TNFα alone increases Schwann cell activation (measured by Schwann cell proliferation, migration, and activation markers), which can be inhibited by neutralizing TNFα. Cancer- or TNFα-activated Schwann cells release pro-nociceptive mediators such as TNFα and nerve growth factor (NGF). Activated Schwann cells induce nociceptive behaviors in mice, which is alleviated by blocking TNFα. Our study suggests that TNFα promotes cancer proliferation, progression, and nociception at least partially by activating Schwann cells. Inhibiting TNFα or Schwann cell activation might serve as therapeutic approaches for the treatment of oral cancer and associated pain.

Social isolation stress facilitates chemically induced oral carcinogenesis

Social isolation has affected a large number of people and may lead to impairment of physical and mental health. Although stress resulting from social isolation may increase cancer progression, its interference on tumorigenesis is poorly known. In this study, we used a preclinical model to evaluate the effects of social isolation stress on chemically induced oral carcinogenesis. Sixty-two 21-day-old male Wistar rats were divided into isolated and grouped groups. After 90 days of age, the rats from both groups underwent oral carcinogenesis with 4-nitroquinoline 1-oxide (4NQO) for 20 weeks. All rats were assessed for depressive-like behavior and euthanized for oral squamous cell carcinoma (OSCC) diagnosis and measurement of inflammatory mediators in the tumor microenvironment. Social isolation stress increased the OSCC occurrence by 20.4% when compared to control. Isolated rats also showed higher tumor volume and cachexia than the grouped rats. Social isolation did not induce changes in the depressive-like behavior after carcinogenic induction. Tumors from stressed rats had increased levels of the inflammatory mediators, TNF-alpha, IL1-beta and MCP-1. The concentrations of TNF-alpha and MCP-1 were significantly increased in the large tumors from isolated animals. Higher tumor levels of TNF-alpha, IL-6, IL1-beta and MCP-1 were positively correlated with OSCC growth. This study provides the first evidence that social isolation stress may facilitate OSCC occurrence and tumor progression, an event accompanied by increased local levels of inflammatory mediators.

[6]-Gingerol impedes 7,12-dimethylbenz(a)anthracene-induced inflammation and cell proliferation-associated hamster buccal pouch carcinogenesis through modulating Nrf2 signaling events

The present study examines the chemopreventive role of [6]-gingerol, an active component of ginger, on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch (HBP) carcinogenesis models. The HBP has been developed with an addition of 0.5% of DMBA to the HBP area three times per week, up to the end of the 16th experimental week. At the end of the experiment, we noticed 100% tumor incidence and precancerous lesions, such as dysplasia, hyperplasia, keratosis, and well-differentiated squamous cell carcinoma, in DMBA-induced HBP. Furthermore, we observed that [6]-gingerol inhibited the increased thiobarbituric acid-reactive substances and decreased antioxidant levels in DMBA-induced hamsters. Moreover, [6]-gingerol inhibits DMBA-exposed over expression of inflammatory markers (inducible nitric oxide synthase, interleukin [IL]-1β, IL-6, cyclooxygenase-2, and tumor necrosis factor-α) and cell proliferation markers (cyclin D1, proliferating cell nuclear antigen); induces proapoptotic markers in HBP. Nuclear factor erythroid-2-related factor-2 (Nrf2) is a major antioxidant transcription factor, which regulates the antioxidant gene-dependent scavenge of tumor proliferation and apoptosis. Overexpression of Nrf2 signaling plays a pivotal role and can be a novel target in preventing carcinogenesis. In this study, [6]-gingerol restores the DMBA-induced depletion of Nrf2 signaling and thereby prevents buccal pouch carcinogenesis in hamsters. These results point out that [6]-gingerol impedes the responses of inflammatory and cell proliferation-associated progression of cancer through the action of Nrf2 signaling.

Oral Neutrophils: Underestimated Players in Oral Cancer

The composition of the oral milieu reflects oral health. Saliva provides an environment for multiple microorganisms, and contains soluble factors and immune cells. Neutrophils, which rapidly react on the changes in the microenvironment, are a major immune cell population in saliva and thus may serve as a biomarker for oral pathologies. This review focuses on salivary neutrophils in the oral cavity, their phenotype changes in physiological and pathological conditions, as well as on factors regulating oral neutrophil amount, activation and functionality, with special emphasis on oral cancer and its risk factors.

Expression of invadopodia markers can identify oral lesions with a high risk of malignant transformation

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor of the oral cavity and is usually preceded by a range of premalignant tissue abnormalities termed oral potentially malignant disorders. Identifying malignant transformation is critical for early treatment and consequently improved survival and decreased morbidity. Invadopodia (INV) are specialized subcellular structures required for cancer cell invasion. We developed a new method to visualize INV in keratinocytes using fluorescent immunohistochemistry (FIHC) and semi‐automated images analysis. The presence of INV was used to determine the risk of malignant transformation. We analyzed 145 formalin‐fixed, paraffin‐embedded (FFPE) oral biopsy samples from 95 patients diagnosed as nondysplastic, dysplastic, and OSCC including 49 patients whose lesions transformed to OSCC (progressing) and 46 cases that did not transform to OSCC (control). All samples were stained for Cortactin, tyrosine kinase substrate with five SH3 domains (Tks5) and matrix metallopeptidase 14 (MMP14) using FIHC, imaged using confocal microscopy and analyzed using a multichannel colocalization analysis. The areas of colocalization were used to generate an INV score. Using the INV score, we were able to identify progressing lesions with a sensitivity of 75–100% and specificity of 72–76%. A positive INV score was associated with increased risk of progression to OSCC. Our results suggest that INV markers can be used in conjunction with the current diagnostic standard for early detection of OSCC.