Oral Cancer and Oral Precancerous Lesions in Inflammatory Bowel Diseases: A Systematic Review

Mucocutaneous manifestations of inflammatory bowel disease

Mucocutaneous manifestations can be indicative of a variety of gastrointestinal diseases, and the dermatologist needs to know how to recognize them to refer the right patients to the gastroenterologist. Conversely, the gastroenterologist is often confronted with mucocutaneous lesions that raise the question of a possible association with a known digestive disease. Among the extra-intestinal manifestations of inflammatory bowel disease (IBD), mucocutaneous manifestations are the most common. This review will provide a breakdown by classifying them into 4 groups: 1) reactive manifestations, which include neutrophilic dermatoses, aphthous stomatitis, erythema nodosum, and vasculitis; 2) Crohn's disease-specific granulomatous skin lesions, which are histologically characterized by tuberculoid granulomas similar to those found in the gastrointestinal tract; 3) nutritional deficiency manifestations secondary to anorexia, malabsorption, loss, and drug interactions; and 3) a variety of autonomous autoimmune or inflammatory skin diseases. Dermatologists may also be involved in the management of the adverse effects of IBD treatments, especially the so-called "paradoxical" psoriatic eruptions.

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.

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.

Systemic Inflammatory Disorders, Immunosuppressive Treatment and Increase Risk of Head and Neck Cancers-A Narrative Review of Potential Physiopathological and Biological Mechanisms

Head and neck cancers (HNCs) are known to present multiple factors likely to influence their development. This review aims to provide a comprehensive overview of the current scientific literature on the interplay between systemic inflammatory disorders, immunosuppressive treatments and their synergistic effect on HNC risk. Both cell-mediated and humoral-mediated systemic inflammatory disorders involve dysregulated immune responses and chronic inflammation and these inflammatory conditions have been associated with an increased risk of HNC development, primarily in the head and neck region. Likewise, the interaction between systemic inflammatory disorders and immunosuppressive treatments appears to amplify the risk of HNC development, as chronic inflammation fosters a tumor-promoting microenvironment, while immunosuppressive therapies further compromise immune surveillance and anti-tumor immune responses. Understanding the molecular and cellular mechanisms underlying this interaction is crucial for developing targeted prevention strategies and therapeutic interventions. Additionally, the emerging field of immunotherapy provides potential avenues for managing HNCs associated with systemic inflammatory disorders, but further research is needed to determine its efficacy and safety in this specific context. Future studies are warranted to elucidate the underlying mechanisms and optimize preventive strategies and therapeutic interventions.

Men with Crohn's disease may have an increased risk for head and neck squamous cell carcinoma - a nationwide register study

OBJECTIVE

Our goal was to study inflammatory bowel disease (IBD) patients' risk of head and neck squamous cell carcinoma (HNSCC), compared to general population.

MATERIALS AND METHODS

We performed a retrospective nationwide register-based study of Finnish individuals diagnosed with IBD between the years 1995 and 2015. The standardized incidence ratio (SIR) of HNSCC was calculated by comparing the cohort's complementary age-year-sex-person-year incidence to that of the whole Finnish population.

RESULTS

About 70,567 patients were diagnosed with IBD (Crohn's disease or ulcerative colitis). Later, 89 of them were diagnosed with HNSCC with mean time of 6.82 years. The incidence of HNSCC was increased in IBD patients compared to the Finnish population expectation (SIR 1.3, 95% CI 1.065-1.614, P = 0.062). When calculating Crohn's disease and ulcerative colitis separately as well as men and women separately, the incidence was particularly increased for men with Crohn's disease (SIR 1.951, 95% CI 1.216-2.935, P = 0.025).

CONCLUSION

An increased risk for HNSCC was found in men with Crohn's disease compared to the Finnish population expectations.

CLINICAL RELEVANCE

This study provides information that would improve follow-up protocols and treatment guidelines of IBD.

Towards multiomic analysis of oral mucosal pathologies

Oral mucosal pathologies comprise an array of diseases with worldwide prevalence and medical relevance. Affecting a confined space with crucial physiological and social functions, oral pathologies can be mutilating and drastically reduce quality of life. Despite their relevance, treatment for these diseases is often far from curative and remains vastly understudied. While multiple factors are involved in the pathogenesis of oral mucosal pathologies, the host's immune system plays a major role in the development, maintenance, and resolution of these diseases. Consequently, a precise understanding of immunological mechanisms implicated in oral mucosal pathologies is critical (1) to identify accurate, mechanistic biomarkers of clinical outcomes; (2) to develop targeted immunotherapeutic strategies; and (3) to individualize prevention and treatment approaches. Here, we review key elements of the immune system's role in oral mucosal pathologies that hold promise to overcome limitations in current diagnostic and therapeutic approaches. We emphasize recent and ongoing multiomic and single-cell approaches that enable an integrative view of these pathophysiological processes and thereby provide unifying and clinically relevant biological signatures.

Binding sites of miRNA on the overexpressed genes of oral cancer using 7mer-seed match

The microRNAs having a length of ~ 19-22 nucleotides are the small, non-coding RNAs. The evolution of microRNAs in many disorders may hold the key to tackle complex challenges. Oral cancer belongs to the group of head and neck cancer. It occurs in the mouth region that appears as an ulcer. In this study, we collected information on the overexpressed genes of oral cancer. The coding sequences of the genes were derived from NCBI and the entire set of human microRNAs present in miRBASE 21 was retrieved. The human microRNAs that can target the overexpressed genes of oral cancer were determined with the aid of our in-house software. The interaction between microRNAs and the overexpressed genes was evaluated with 7mer-m8 model of microRNA targeting. The genes DKK1 and APLN paired with only one miRNA i.e., miR-447 and miR-6087, respectively. But the genes INHBA and MMP1 were found to be targeted by 2 miRNAs, while the genes FN1, FAP, TGFPI, COL4A1, COL4A2, and LOXL2 were found to be targeted by 16, 5, 9, 18, 29, and 11 miRNAs. Subsequently, several measures such as free energy, translation efficiency, and cosine similarity metric were used to estimate the binding process. It was found that the target region's stability was higher than the upstream and downstream zones. The overexpressed genes' GC contents were calculated, revealing that the codons in target miRNA region were overall GC rich as well as GC3 rich. Lastly, gene ontology was performed to better understand each gene's involvement in biological processes, molecular function, and cellular component. Our study showed the role of microRNAs in gene repression, which could possibly aid in the prognosis and diagnosis of oral cancer.

Inflammatory Bowel disease promote oral cancer and pharyngeal cancer: new evidence of Mendelian randomization

BACKGROUND

Evidence from observational studies shows that inflammatory bowel disease (IBD) [comprising ulcerative colitis (UC) and Crohn's disease (CD)] is a risk factor to Oral cavity and pharyngeal cancer (OC&PC) [comprising Oral cavity cancer (OCC) and Oropharyngeal cancer (OPC)], but it is unclear whether these diseases have potential causality.

OBJECTIVES

We aimed to explore the causal relationship between IBD and OC&PC.

MATERIALS AND METHODS

A mendelian randomized (MR) study was performed to estimate the causal relationship between IBD and OC&PC.

RESULTS

The potential causal relationship was statistically significant between IBD and OCC (OR = 1.14, 95% confidence interval (CI): 1.02-1.27, p = .02), UC and OCC (OR = 1.13, 95% CI: 1.01-1.27, p = .03), respectively. There was a universal null effect of IBD on OC&PC (IBD: OR = 1.01, 95%CI: 0.93-1.10, p = .74; UC: OR = 1.00, 95%CI: 0.92-1.10, p = .94; CD: OR = 1.02, 95%CI: 0.94-1.09, p = .69), and IBD on OPC (IBD: OR = 0.93, 95%CI: 0.81-1.06, p = 0.26; UC: OR = 0.90, 95%CI: 0.79-1.03, p = .12; CD: OR = 1.04, 95%CI: 0.94-1.15, p = .44).

CONCLUSIONS AND SIGNIFICANCE

MR analyses support new evidence indicating there may be a positive causal effect of IBD (including UC) on OCC. Further investigation of the potential biological mechanisms is necessary.

Oral manifestations of inflammatory bowel disease: the neglected piece of the puzzle

Inflammatory bowel disease (IBD) is a chronic relapsing remitting autoimmune disease including Crohn's disease and ulcerative colitis. IBD is associated with various extra-intestinal manifestations including oral manifestation. To date, only limited studies addressing the characteristics of the oral manifestations are available. The aim of the present review is to report the oral manifestations and their characteristics in IBD. A Medline/PubMed and Embase databases search were conducted and all relevant studies were extracted and analyzed. Overall, the oral manifestations in IBD were mostly associated with Crohn's disease rather than Ulcerative colitis where their prevalence ranged from 8 to 50%. Specific lesions for Crohn's disease include mucosal tags, cobblestoning and deep linear ulcerations with vertical fissures, while for ulcerative colitis, pyostomatisis vegetans was more disease specific. Notably, most of the oral manifestations were unrelated to disease activity, however more data are needed to accurately assess this correlation. Oral manifestations among IBD patients are not uncommon as Crohn's disease account for most of them. More data are warranted to precisely characterize their prevalence and association to intestinal activity.

Oral Manifestations of Inflammatory Bowel Disease and the Role of Non-Invasive Surrogate Markers of Disease Activity

Inflammatory bowel disease (IBD), which includes Crohn's disease (CD) and ulcerative colitis (UC), can be associated with several extra-intestinal manifestations requiring a multidisciplinary management both in terms of work-up and therapy. Oral lesions are common in patients with IBD, with a prevalence ranging from 5% to 50%. These can represent an oral location of IBD as well as a side-effect of drugs used to treat the intestinal disease. Oral manifestations, occurring in patients with IBD, can be divided in nonmalignant, specific, and non-specific ones, and malignant lesions. While there is undoubtedly a need to search for an IBD in patients with oral lesions associated with intestinal symptoms, the work-up of those with an exclusive oral lesion should be personalized. Fecal calprotectin is a non-invasive marker of intestinal inflammation and may be used to select which patients need to undergo endoscopic examination, thereby avoiding unnecessary investigations. The pharmacological armamentarium to treat oral lesions associated with IBD includes topical or systemic corticosteroids, immunosuppressive agents, and biologic drugs.

Long non‑coding RNAs are novel players in oral inflammatory disorders, potentially premalignant oral epithelial lesions and oral squamous cell carcinoma (Review)

In recent years, a large number of studies have shown that the abnormal expression of long non‑coding (lnc)RNAs can lead to a variety of different diseases, including inflammatory disorders, cardiovascular disease, nervous system diseases, and cancers. Recent research has demonstrated the biological characteristics of lncRNAs and the important functions of lncRNAs in oral inflammation, precancerous lesions and cancers. The present review aims to explore and discuss the potential roles of candidate lncRNAs in oral diseases by summarizing multiple lncRNA profiles in diseased and healthy oral tissues to determine the altered lncRNA signatures. In addition, to highlight the exact regulatory mechanism of lncRNAs in oral inflammatory disorders, potentially premalignant oral epithelial lesions and oral squamous cell carcinoma. The detection of lncRNAs in oral samples has the potential to be used as a diagnostic and an early detection tool for oral diseases. Furthermore, lncRNAs are promising future therapeutic targets in oral diseases, and research in this field may expand in the future.

Noninvasive assessment of oral lesions using elastic light single-scattering spectroscopy: a pilot study

PURPOSE

In the present study, we investigated the potential application of elastic light single-scattering spectroscopy (ELSSS) as a noninvasive, adjunctive tool to differentiate between malignant and benign oral lesions in vivo.

METHODS

ELSSS spectra were acquired from 52 oral lesions of 47 patients prior to surgical biopsy using a single optical fiber probe. The sign of the spectral slope was used as a diagnostic parameter and was compared to the histopathology findings to obtain sensitivity and specificity of the ELSSS system in differentiating between benign and malignant tissues.

RESULTS

The sign of the spectral slope was positive for the benign tissues and negative for the malignant tissues. Nine malignant lesions and one high-grade dysplasia were correctly classified as cancerous. Six out of the ten low-grade dysplasia were correctly classified as cancerous, and four of them were misclassified as benign. Thirty benign lesions were correctly classified as benign, and two were misclassified as malignant. Our results indicate that the sign of the spectral slope enables the differentiation between malignant and benign oral lesions with a sensitivity of 80% and specificity of 94%.

CONCLUSIONS

ELSSS has the potential to be developed as an adjunctive screening tool in the noninvasive evaluation of oral lesions in vivo. This new diagnostic system may reduce the number of unnecessary biopsies.

Inferring novel genes related to oral cancer with a network embedding method and one-class learning algorithms

Oral cancer (OC) is one of the most common cancers threatening human lives. However, OC pathogenesis has yet to be fully uncovered, and thus designing effective treatments remains difficult. Identifying genes related to OC is an important way for achieving this purpose. In this study, we proposed three computational models for inferring novel OC-related genes. In contrast to previously proposed computational methods, which lacked the learning procedures, each proposed model adopted a one-class learning algorithm, which can provide a deep insight into features of validated OC-related genes. A network embedding algorithm (i.e., node2vec) was applied to the protein-protein interaction network to produce the representation of genes. The features of the OC-related genes were used in the training of the one-class algorithm, and the performance of the final inferring model was improved through a feature selection procedure. Then, candidate genes were produced by applying the trained inferring model to other genes. Three tests were performed to screen out the important candidate genes. Accordingly, we obtained three inferred gene sets, any two of which were different. The inferred genes were also different from previous reported genes and some of them have been included in the public Oral Cancer Gene Database. Finally, we analyzed several inferred genes to confirm whether they are novel OC-related genes.

Crohn's Disease and the Risk of Cancer

Crohn's disease is associated with various intestinal and extraintestinal malignancies. This article reviews the current literature regarding Crohn's disease and subsequent risk of cancer formation. Recognition of risk factors (both modifiable and unmodifiable) is essential for prevention and appropriate screening. Future investigations into the molecular mechanisms associated with Crohn-related malignancy will provide additional insight into carcinogenesis, potential for early intervention, and identification of at-risk patients.

Relationship of infiltrating intraepithelial T lymphocytes in the diagnosis of oral lichen planus versus oral epithelial dysplasia: a pilot study

OBJECTIVE

The aim of this study was to identify the type and distribution of CD4+ and CD8+ T lymphocytes in oral mucosal specimens to potentially distinguish between underlying alterations or patterns in oral epithelial dysplasia and oral lichen planus.

STUDY DESIGN

This pilot study included 10 archived tissue samples that were received at the University of North Carolina Oral and Maxillofacial Pathology Laboratory and were diagnosed as oral lichen planus and moderate to severe epithelial dysplasia. Dual staining with CD4 and CD8 antibodies was carried out on each case. Slides were scanned in the Aperio ScanScope FL (Leica Biosystems, Wetzlar, Germany) and archived. Histomorphometric analysis was performed to detect inflammatory cells expressing CD4 and CD8 biomarkers in the epithelial and connective tissue regions.

RESULTS

No differences were found in the amount and ratio of CD4+/CD8+ lymphocytes among the 3 groups analyzed; however, the intraepithelial CD8+ lymphocyte distribution was strikingly different between lichen planus and moderate to severe epithelial dysplasia.

CONCLUSIONS

The localization of CD8+ cells can be potentially useful as an adjunctive diagnostic procedure to distinguish oral epithelial dysplasia from other inflammatory entities, such as lichen planus.

Liquid Biopsy in Oral Cancer

Oral cancer is one of the most prevalent forms of cancer worldwide. Carcinogenesis is a complex process, in which heterogeneity plays an important role in the development and progression of the disease. This review provides an overview of the current biological and clinical significance of circulating tumour cells (CTCs), circulating tumour DNA (ctDNA), and exosomes for diagnosis and prognosis of oral cancer. We highlight the importance of liquid biopsy—using blood and saliva—which represents a potential alternative to solid biopsy for diagnosis and prognosis. Moreover, liquid biomarkers allow for the real-time monitoring of tumour evolution and therapeutic responses, initiating the era of personalized medicine. However, in oral cancer, the impact of liquid biopsies in clinical settings is still limited, requiring further studies to discover the best scenario for its clinical use.

Kallikrein-related peptidase 4 contributes to the tumor metastasis of oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a disfiguring malignancy and significantly impacts the quality of patient's life. Kallikrein-related peptidase 4 (KLK4), which is closely related to cancers, is highly expressed in OSCC. To explore the biological function of KLK4 in OSCC, a KLK4-specific shRNA was used to silence its endogenous expression, and then the migration and invasion of OSCC cells were explored. Results of our study showed that silencing KLK4 inhibited the migration and invasion of OSCC cells. The protein levels of epithelial mesenchymal transition-associated markers and proteases were also altered by KLK4 silencing. Further study showed that the phosphatidylinositol 3-kinase (PI3 K)/protein kinase B (AKT) signaling pathway was involved in the function of KLK4. Treatment with a PI3 K/AKT activator reversed the migration-inhibitory effect of KLK4 shRNA. Our study suggests that KLK4 may contribute to the metastasis of OSCC through the PI3 K/AKT signaling pathway.

Practical Approaches to "Top-Down" Therapies for Crohn's Disease

Crohn's disease (CD) is a chronic, progressive, and disabling disease that leads in most cases to the development of bowel damage presenting as a fistula, abscess, or stricture. For years, therapy for Crohn's disease has been based on a "step-up" approach, in which anti-TNF agents are administered after the failure of steroids and immunosuppressants. However, recent studies have suggested that early introduction of anti-TNF agents combined with immunosuppressants can modify the natural history of the disease. Patients who could benefit more of this "top-down" strategy would be those at elevated risk of a complicated or severe inflammatory bowel disease or with factors that can predict an aggressive disease course. Therefore, the management of a patient with CD should be personalized, taking into account the patient's specific characteristics and comorbidities, disease activity, site and behavior of the disease, and predictable factors of poor prognosis. A balance between medication and potential adverse effects should be achieved, trying to avoid under or overtreatment, always discussing the different therapeutic options with the patient. The natural history of ulcerative colitis differs from CD and, to date, there is not much scientific evidence on the use of early combined immunosuppression.

Experts Opinion on the Practical Use of Azathioprine and 6-Mercaptopurine in Inflammatory Bowel Disease

The relevance of azathioprine and 6-mercaptopurine therapy in inflammatory bowel disease, Crohn's disease, and ulcerative colitis, has been challenged in recent publications. In this article, a panel of experts gives advice, based on the relevant literature, on indications and practical use of azathioprine/6-mercaptopurine, prevention, and management of drug adverse reactions and special situations such as vaccination, pregnancy, and lactation.

Use of biologics and chemotherapy in patients with inflammatory bowel diseases and cancer

Patients with inflammatory bowel disease have an additional risk of developing cancer compared with the general population. This is due to local chronic inflammation that leads to the development of gastrointestinal cancers and the use of thiopurines, associated with a higher risk of lymphoproliferative disorders, skin cancers, or uterine cervical cancers. Similar to the general population, a previous history of cancer in inflammatory bowel disease patients increases the risk of developing a secondary cancer. Large studies have not shown an increased risk of cancer in patients treated with biologics. In this review we discuss the prevention and treatment of cancer in patients with inflammatory bowel disease.

Extraintestinal manifestations of inflammatory bowel disease

Inflammatory bowel disease (IBD) is a systemic disease, and it not only affects the gastrointestinal tract, but also may show a variety of extraintestinal manifestations (EIMs). EIMs can involve multiple systems. This paper reviews the EIMs of IBD for a more comprehensive understanding of IBD to guide its clinical diagnosis and treatment.