An Overview on Current Non-invasive Diagnostic Devices in Oral Oncology

Comprehensive insights into oral squamous cell carcinoma: Diagnosis, pathogenesis, and therapeutic advances

Oral squamous cell carcinoma (OSCC) is considered the most common type of head and neck squamous cell carcinoma (HNSCC) as it holds 90 % of HNSCC cases that arise from multiple locations in the oral cavity. The last three decades witnessed little progress in the diagnosis and treatment of OSCC the aggressive tumor. However, in-depth knowledge about OSCC's pathogenesis, staging & grading, hallmarks, and causative factors is a prime requirement in advanced diagnosis and treatment for OSCC patients. Therefore present review was intended to comprehend the OSCCs' prevalence, staging & grading, molecular pathogenesis including premalignant stages, various hallmarks, etiology, diagnostic methods, treatment (including FDA-approved drugs with the mechanism of action and side effects), and theranostic agents. The current review updates that for a better understanding of OSCC progress tumor-promoting inflammation, sustained proliferative signaling, and growth-suppressive signals/apoptosis capacity evasion are the three most important hallmarks to be considered. This review suggests that among all the etiology factors the consumption of tobacco is the major contributor to the high incidence rate of OSCC. In OSCC diagnosis biopsy is considered the gold standard, however, toluidine blue staining is the easiest and non-invasive method with high accuracy. Although there are various therapeutic agents available for cancer treatment, however, a few only are approved by the FDA specifically for OSCC treatment. The present review recommends that among all available OSCC treatments, the antibody-based CAR-NK is a promising therapeutic approach for future cancer treatment. Presently review also suggests that theranostics have boosted the advancement of cancer diagnosis and treatment, however, additional work is required to refine the role of theranostics in combination with different modalities in cancer treatment.

A simple and effective method for smartphone-based detection of polyamines in oral cancer

Oral cancer accounts for 50%-70% of all cancer-related deaths in India and ranks sixth among the most frequent cancers globally. Roughly 90% of oral malignancies are histologically arise from squamous cells and are therefore called oral squamous cell carcinoma. Organic polycations known as biogenic polyamines, for example, putrescine (Put), spermidine (Spd), and spermine (Spm), are vital for cell proliferation, including gene expression control, regulation of endonuclease-mediated fragmentation of DNA, and DNA damage inhibition. Higher Spm and Spd levels have been identified as cancer biomarkers for detecting tumour development in various cancers. The current study utilises tannic acid, a polyphenolic compound, as a reducing and capping agent to fabricate AuNPs via a one-step microwave-assisted synthesis. The fabricated TA@AuNPs were utilised as a nanoprobe for colourimetric sensing of polyamines in PBS. When TA@AuNPs are added to the polyamine, the amine groups in polyamines interact with the phenolic groups of TA@AuNPs via hydrogen bonding or electrostatic interactions. These interactions cause the aggregation of TA@AuNPs, resulting in a red shift of the Surface Plasmon Resonance band of TA@AuNPs from 530 nm to 560 nm. The nanoprobe was found to be highly specific for Spm at low concentrations. TA@AuNPs were able to detect Spm successfully in artificial saliva samples. On recording the RGB values of the sensing process using a smartphone app, it was found that as the nanoparticles aggregated due to the presence of Spm, the intensity of theR-value decreased, indicating the aggregation of TA@AuNPs due to interaction with the polyamine.

Novel ferroptosis signature for improving prediction of prognosis and indicating gene targets from single-cell level in oral squamous cell carcinoma

Background

Oral squamous cell carcinoma (OSCC) is one of the most prevalent kinds of cancers. Therefore, there is a pressing need to create a new risk scoring model to personalize the prognosis of OSCC patients and screen for patient-specific therapeutic agents and molecular targets.

Methods

Firstly, A series of bioinformatics was performed to construct a novel ferroptosis-related prognostic model; Further, drug sensitivity analysis was used to screen for specific therapeutic agents for OSCC; Single-cell analysis was employed to investigate the enrichment of FRDEGs (ferroptosis-related differentially expressed genes) in the OSCC microenvironment; Finally, various experiments were conducted to screen and validate molecular therapeutic targets for OSCC.

Results

In this study, we constructed a novel 10-FRDEGs risk scoring model. Base on the risk scoring model, we founded three potential chemotherapeutic agents for OSCC: 5Z)-7-Oxozeaenol, AT-7519, KIN001-266; In addition, FRDEGs were enriched in the epithelial cells of OSCC. Finally, we found that CA9 and CAV1 could regulate OSCC proliferation, migration and ferroptosis in vitro.

Conclusion

A novel 10-FRDEGs risk scoring model can predict the prognosis of patients with OSCC.Further,5Z)-7-Oxozeaenol, AT-7519, KIN001-266 are potential chemotherapeutic agents for OSCC.Moreover, we identified CA9、CAV1 as potential molecular target for the treatment of OSCC.Our findings provide new directions for prognostic assessment and precise treatment of oral cell squamous carcinoma.

A Prospective Double-Blinded Comparison of Reflectance Confocal Microscopy with Conventional Histopathology for In Vivo Assessment in Oral Cancer

PURPOSE

We investigated reflectance confocal microscopy (RCM) as a possible noninvasive approach for the diagnosis of cancer and real-time assessment of surgical margins.

EXPERIMENTAL DESIGN

In a phase I study on 20 patients, we established the RCM imaging morphologic features that distinguish oral squamous cell carcinoma (OSCC) from normal tissue with a newly developed intraoral RCM probe. Our subsequent phase II prospective double-blinded study in 60 patients tested the diagnostic accuracy of RCM against histopathology. Five RCM videos from the tumor and five from normal surrounding mucosa were collected on each patient, followed by a 3-mm punch biopsy of the imaged area. An experienced RCM reader, who was blinded to biopsy location and histologic diagnosis, examined the videos from both regions and classified each as "tumor" or "not tumor" based on RCM features established in phase I. Hematoxylin and eosin slides from the biopsies were read by a pathologist who was blinded to RCM results. Using histology as the gold standard, we calculated the sensitivity and specificity of RCM.

RESULTS

We report a high agreement between the blinded readers (95% for normal tissue and 81.7% for tumors), high specificity (98.3%) and negative predictive values (96.6%) for normal tissue identification, and high sensitivity (90%) and positive predictive values (88.2%) for tumor detection.

CONCLUSIONS

RCM imaging is a promising technology for noninvasive in vivo diagnosis of OSCC and for real-time intraoperative evaluation of mucosal surgical margins. Its inherent constraint, however, stems from the diminished capability to evaluate structures located at more substantial depths within the tissue.

Relationship between mastication and malnutrition in community-dwelling older adults: a meta-analysis

PURPOSE

To determine the relationship between mastication and malnutrition in community-dwelling older adults.

RESEARCH STRATEGIES

To establish the eligibility criteria, the acronym PECOS was used: Population: non-institutionalized older adults; Exposure: older adults with malnutrition; Control: older adults without malnutrition; Outcome: masticatory problems in malnourished older adults; Study types: observational studies.

SELECTION CRITERIA

It selected studies assessing malnutrition and mastication difficulties in non-institutionalized adults over 60 years old, of both sexes. Mastication and malnutrition were evaluated with questionnaires on self-reported symptoms and clinical and instrumental assessments. There were no restrictions on language, year of publication, or ethnicity.

DATA ANALYSIS

The included studies were evaluated for methodological quality with the Joanna Briggs Institute tool for cross-sectional studies. For the cross-sectional studies included, the odds ratio (OR) was calculated with 95% confidence intervals.

RESULTS

After searching the databases, 692 references were retrieved, with three studies selected for quantitative and qualitative analysis. The values obtained in the meta-analysis for association show that malnutrition and mastication difficulties were 2.21 times as likely to occur (OR = 2.21; 95%CI = 0.93 - 5.26; I2 = 94%) as individuals without malnutrition (p < 0.001). The assessment of the risk of bias presented a high-risk, a moderate-risk, and a low-risk study. The certainty of evidence was rated very low with the GRADE tool.

CONCLUSION

Individuals at risk of malnutrition are 2.21 times as likely to have mastication difficulties.

Determination of the anticancer activity of standardized extract of Centella asiatica (ECa 233) on cell growth and metastatic behavior in oral cancer cells

Background and purpose

The anticancer drugs used for oral cancer treatment present many disadvantages, such as low solubility, low permeability, and poor bioavailability. However, the anticancer activity of ECa 233 has not been widely studied. Therefore, the anticancer activity of ECa 233 was investigated in this study.

Experimental approach

MTT assay was carried out to determine cell viability. Characterizations of cell apoptosis were monitored using DAPI and FDA staining and Hoechst 33258 and AO staining. Confirmation of the apoptosis-induced KON cells was done using annexin V-FITC staining, and ROS generation was determined by DCFDA staining. Cell death and the cell cycle arrest activity of ECa 233 were demonstrated by a flow cytometer. The anti-migration and anti-invasion properties of ECa 233 were examined. The anti-proliferative of ECa 233 was investigated. Cellular uptake of ECa 233 was measured by TEER values. The pharmacokinetics of ECa 233 were estimated using the pkCSM web server.

Findings/Results

ECa 233 decreased the KON cell viability. Morphological analysis showed the KON cells' loss of cell stability and structure, disorganized nucleus and cytoplasm, and induced cell death. ECa 233 acted as a cell cycle arrest in the G0/G1 phase and reduced the migration and invasion ability in KON cells. TEER values significantly increased in KON cells, which decreased cell colony and multicellular spheroid formations. The pharmacokinetic profiles of the main components are of interest for future usage.

Conclusion and implication

ECa 233 can be used as an alternative therapy as well as a medicinal plant selected for sensitizing oral cancer cells to chemotherapy.

Chemopreventive and Biological Strategies in the Management of Oral Potentially Malignant and Malignant Disorders

Oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC) represent a significant global health burden due to their potential for malignant transformation and the challenges associated with their diagnosis and treatment. Chemoprevention, an innovative approach aimed at halting or reversing the neoplastic process before full malignancy, has emerged as a promising avenue for mitigating the impact of OPMD and OSCC. The pivotal role of chemopreventive strategies is underscored by the need for effective interventions that go beyond traditional therapies. In this regard, chemopreventive agents offer a unique opportunity to intercept disease progression by targeting the molecular pathways implicated in carcinogenesis. Natural compounds, such as curcumin, green tea polyphenols, and resveratrol, exhibit anti-inflammatory, antioxidant, and anti-cancer properties that could make them potential candidates for curtailing the transformation of OPMD to OSCC. Moreover, targeted therapies directed at specific molecular alterations hold promise in disrupting the signaling cascades driving OSCC growth. Immunomodulatory agents, like immune checkpoint inhibitors, are gaining attention for their potential to harness the body's immune response against early malignancies, thus impeding OSCC advancement. Additionally, nutritional interventions and topical formulations of chemopreventive agents offer localized strategies for preventing carcinogenesis in the oral cavity. The challenge lies in optimizing these strategies for efficacy, safety, and patient compliance. This review presents an up to date on the dynamic interplay between molecular insights, clinical interventions, and the broader goal of reducing the burden of oral malignancies. As research progresses, the synergy between early diagnosis, non-invasive biomarker identification, and chemopreventive therapy is poised to reshape the landscape of OPMD and OSCC management, offering a glimpse of a future where these diseases are no longer insurmountable challenges but rather preventable and manageable conditions.

Comprehensive analysis of m6A modifications in oral squamous cell carcinoma by MeRIP sequencing

N6-methyladenosine (m6A) modifications are the most abundant internal modifications of mRNA and have a significant role in various cancers; however, the m6A methylome profile of oral squamous cell carcinoma (OSCC) in the mRNA-wide remains unknown. In this study, we examined the relationship between m6A and OSCC. Four pairs of OSCC and adjacent normal tissues were compared by Methylated RNA immunoprecipitation sequencing (MeRIP-seq). Gene Ontology, Kyoto Encyclopedia of Genes and Genomes (KEGG), and Ingenuity Pathway Analysis (IPA) analyses were used to further analyze the MeRIP-seq data. A total of 2,348 different m6A peaks were identified in the OSCC group, including 85 m6A upregulated peaks and 2,263 m6A downregulated peaks. Differentially methylated m6A binding sites were enriched in the coding sequence in proximity to the stop codon of both groups. KEGG analysis revealed genes with upregulated m6A-modified sites in the OSCC group, which were prominently associated with the forkhead box O (FOXO) signaling pathway. Genes containing downregulated m6A-modified sites were significantly correlated with the PI3K/Akt signaling pathway, spliceosome, protein processing in the endoplasmic reticulum, and endocytosis. IPA analysis indicated that several genes with differential methylation peaks form networks with m6A regulators. Overall, this study established the mRNA-wide m6A map for human OSCC and indicated the potential links between OSCC and N6-methyladenosine modification.

Epidemiological evaluation of patient compliance regarding oral health and hygiene during the COVID-19 period

This work aimed to report values on oral hygiene habits at home during the pandemic and compare the differences between previous oral hygiene habits. A total of 1,136 questionnaires were filled in via a link sent through email to the patients. The answers show that although they had more time during the pandemic, they spent less time on dental and tongue hygiene. Dental and tongue hygiene are key to maintaining systemic health. The questionnaire was sent by e-mail to 1,136 male and female patients throughout Italy. Demonstrate and understand whether patients during the pandemic cleaned and spent time cleaning and maintaining their teeth and tongue hygiene. The questionnaire testifies to the fact that it is not the time but the patient's compliance and motivation that makes the difference.

OBJECTIVE

This work aimed to report values regarding oral hygiene habits at home during the pandemic and compare the difference with previous oral hygiene habits.

METHODS

This study was performed anonymously and had patients answer an online questionnaire. The questionnaire consisted of 11 closed-answer questions (except 1) concerning oral hygiene habits at home at the time of COVID-19 and participant characteristics, including gender and age. A total of 1,136 questionnaires were filled in via a link sent by email to the patients.

RESULTS

Among the 1,136 patients examined, 32.4% (372) were male and 67.6% (775) were female, and almost half (47.9%) of the patients who answered the questionnaire were aged 18-40 years. Patients who participated in our survey were asked questions related to dental and tongue hygiene. The answers showed that although they had more time during the pandemic, they brushed their teeth less and did not brush their tongues regularly.

CONCLUSION

Patients with periodontal problems usually have less time for brushing and do not have good plaque control. The questionnaire showed the opposite, such that the patient's compliance and motivation matters more than time. Thus, dentists and dental hygienists must encourage and make patients understand the importance of oral hygiene at home.

A combined autofluorescence and diffuse reflectance spectroscopy for mucosa tissue diagnosis: Dual-distance system and data-driven decision

Combined autofluorescence (AF) and diffuse reflectance (DR) spectroscopies have been expected to offer enhanced diagnostic accuracies for noninvasive early detection of mucosa lesions, that is, oral cavity carcinoma and cervical carcinoma. This work reports on a hybrid AF and DR spectroscopic system that is developed for quantification and diagnosis of mucosa abnormalities. The system stability and reliability are firstly assessed by phantom experiments, showing a measurement variation lower than 1% within 20 min. In vitro and in vivo validations are then conducted for tissue identification and lesion differentiation. For enhanced decision, a data-driven diagnosis algorithm is explored in pilot under different experimental configurations. The results conclude a promising accuracy of >96% for the in vivo classification as well as an excellent sensitivity of >88% for the in vitro mucosa lesions detection, and demonstrate sound potential of the system in early detection of mucosa lesions.

Piperlongumine Induces Apoptosis and Cytoprotective Autophagy via the MAPK Signaling Pathway in Human Oral Cancer Cells

Oral cancer is a malignant tumor that primarily affects areas such as the lips, tongue, buccal mucosa, salivary gland, and gingiva and has a very high malignancy. Piperlongumine (PL), isolated from long pepper (Piper longum L.), is a natural alkaloid with pharmacological effects, such as anti-inflammatory and anti-atherosclerotic effects. The effect and mechanism of PL in oral cancer cell lines has not been explored. Therefore, this study aimed to investigate the mechanism of anticancer effects of PL in the human oral cancer cell lines MC-3 and HSC-4 in vitro. This study demonstrated that PL inhibits cell proliferation by inducing apoptosis and autophagy in human oral cancer cell lines, which was confirmed by the levels of apoptosis- and autophagy-related proteins through Western blotting. Moreover, the pharmacological blockade of autophagy activation by hydroxychloroquine (HCQ), an autophagy inhibitor, significantly improved PL-induced apoptosis in MC-3 cells, suggesting a cytoprotective effect. In addition, activation of the mitogen-activated protein kinase (MAPK) signaling pathway contributed to PL-induced apoptosis. Collectively, the study suggested that combining an autophagy inhibitor with PL treatment can exert effective anticancer properties in oral cancer cells by inducing apoptosis and cytoprotective autophagy via the JNK-mediated MAPK pathway.

Proteomic and phosphoproteomic landscape of salivary extracellular vesicles to assess OSCC therapeutical outcomes

Circulating extracellular vesicles (EVs) have emerged as an appealing source for surrogates to evaluate the disease status. Herein, we present a novel proteomic strategy to identify proteins and phosphoproteins from salivary EVs to distinguish oral squamous cell carcinoma (OSCC) patients from healthy individuals and explore the feasibility to evaluate therapeutical outcomes. Bi-functionalized magnetic beads (BiMBs) with Ti (IV) ions and a lipid analog, 1,2-Distearoyl-3-sn-glycerophosphoethanolamine (DSPE) are developed to efficiently isolate EVs from small volume of saliva. In the discovery stage, label-free proteomics and phosphoproteomics quantification showed 315 upregulated proteins and 132 upregulated phosphoproteins in OSCC patients among more than 2500 EV proteins and 1000 EV phosphoproteins, respectively. We further applied targeted proteomics by coupling parallel reaction monitoring with parallel accumulation-serial fragmentation (prm-PASEF) to measure panels of proteins and phosphoproteins from salivary EVs collected before and after surgical resection. A panel of three total proteins and three phosphoproteins, most of which have previously been associated with OSCC and other cancer types, show sensitive response to the therapy in individual patients. Our study presents a novel strategy to the discovery of effective biomarkers for non-invasive assessment of OSCC surgical outcomes with small amount of saliva.

Multifunctional AuNPs@HRP@FeMOF immune scaffold with a fully automated saliva analyzer for oral cancer screening

Delayed diagnosis of cancer-causing death is a worldwide concern. General diagnosis methods are invasive, time-consuming, and operation complicated, which are not suitable for preliminary screening. To address these challenges, the sensing platform based on immune scaffold and fully automated saliva analyzer (FASA) was proposed for oral cancer screening for the first time by non-invasive detection of Cyfra21-1 in saliva. Through one-step synthesis method with unique covalent and electrostatic adsorption strategy, AuNPs@HRP@FeMOF immune scaffold features multiple functions including antibody carrier, catalytic activity, and signal amplification. Highly integrated FASA with the immune scaffold provides automatic testing to avoid false-positive results and reduce pretreatment time without any user intervention. Compared with the commercial analyzer, FASA has comparable performance for Cyfra21-1 detection with a detection range of 3.1-50.0 ng/mL and R² of 0.971, and superior features in full automation, high integration, time saving and low cost. Oral cancer patients could be distinguished accurately by the platform with an excellent correlation (R² of 0.904) and average RSD (5.578%) without sample dilution. The proposed platform provides an effective and promising tool for cancer screening in point-of-care applications, which can be further extended for biomarker detection in universal body fluids, disease screening, prognosis review and homecare monitoring.

Current advances in noninvasive methods for the diagnosis of oral squamous cell carcinoma: a review

Oral squamous cell carcinoma (OSCC), one of the most common types of cancers worldwide, is diagnosed mainly through tissue biopsy. However, owing to the tumor heterogeneity and other drawbacks, such as the invasiveness of the biopsy procedure and high cost and limited usefulness of longitudinal surveillance, there has been a focus on adopting more rapid, economical, and noninvasive screening methods. Examples of these include liquid biopsy, optical detection systems, oral brush cytology, microfluidic detection, and artificial intelligence auxiliary diagnosis, which have their own strengths and weaknesses. Extensive research is being performed on various liquid biopsy biomarkers, including novel microbiome components, noncoding RNAs, extracellular vesicles, and circulating tumor DNA. The majority of these elements have demonstrated encouraging clinical outcomes in early OSCC detection. This review summarizes the screening methods for OSCC with a focus on providing new guiding strategies for the diagnosis of the disease.

Non-invasive detection of oral potentially malignant and malignant lesions using an optical multispectral screening device

Oral carcinogenesis is a multistep process that usually arises in the superficial epithelial layer covering the lining of the body cavities. The early changes in the oral mucosa reflect as oral precancers or oral potentially malignant disorders (OPMD). The most common OPMD are erythroplakia and leukoplakia, with their chances of malignant transformation being approximately 90% and 10%, respectively. The development of epithelial precancers is initiated through changes in nuclear shape, size, and density of cells and overall thickening of the epithelial layer. Conventional oral examination (COE) with white light is the most common technique for detection of malignant changes in the oral cavity. This often poses a diagnostic challenge for the clinicians in differentiation of normal and early malignant changes. Thus, biopsy of the site is the accepted clinical procedure for diagnosis of the lesion. A major hurdle here is to identify visually, the most malignant location for a biopsy. As the selection of a site is subjective, the chosen site may not always be representative of the disease and this often leads to repeated biopsies and discomfort to the patients. A novel device known as OralScan was recently introduced by Sascan Meditech, Thiruvananthapuram, for screening and early detection of oral cancers. The clinical application of the device in different clinical scenarios are discussed in this case series report.

Identification of salivary autoantibodies as biomarkers of oral cancer with immunoglobulin A enrichment combined with affinity mass spectrometry

Globally, oral cavity squamous cell carcinoma (OSCC) is one of the most common fatal illnesses. Its high mortality is ascribed to the fact that the disease is often diagnosed at a late stage, which indicates an urgent need for approaches for the early detection of OSCC. The use of salivary autoantibodies (autoAbs) as OSCC biomarkers has numerous advantages such as easy access to saliva samples and efficient detection of autoAbs using well-established secondary reagents. To improve OSCC screening, we identified OSCC-associated autoAbs with the enrichment of salivary autoAbs combined with affinity mass spectrometry (MS). The salivary IgA of healthy individuals and OSCC patients was purified with peptide M-conjugated beads and then applied to immunoprecipitated antigens (Ags) in OSCC cells. Using tandem MS analysis and spectral counting-based quantitation, the level of 10 Ags increased in the OSCC group compared with the control group. Moreover, salivary levels of autoAbs to the 10 Ags were determined by a multiplexed bead-based immunoassay. Among them, seven were significantly higher in early-stage OSCC patients than in healthy individuals. A marker panel consisting of autoAbs to LMAN2, PTGR1, RAB13, and UQCRC2 was further developed to improve the early diagnosis of OSCC.

Influence of Nanocurcumin and Photodynamic Therapy Using Nanocurcumin in Treatment of Rat Tongue Oral Squamous Cell Carcinoma Through Histological Examination and Gene Expression of BCL2 and Caspase-3

Background

Oral squamous cell carcinoma (OSCC) is the sixth most common mouth cancer in the world. The aim of the present study is comparing the effects of using Nanocurcumin, and photodynamic therapy (PDT), alone or together in treatment of OSCC in rats.

Methods

Forty Wister male rats were divided into Control (group 1), 650 nm diode Laser only (group 2), Nanocurcumin alone (group 3), and PDT with a combination of laser with Nanocurcumin (group 4). Then, OSCC in the tongue induced by dimethylbenz anthracene (DMBA). The treatments were evaluated clinically, histopathologically, and immunohistochemically through BCL2 and Caspase-3 genes expression.

Results

Positive control with OSCC displayed significant weight loss, while PDT group gained more than nanocurcumin treated groups as well as laser groups comparing with control positive group. The histological examination of the tongue in PDT group showed improvement. In laser group, there were partial loss of surface epithelium with various ulcers and dysplasia and partial improvement by this type of treatment. The tongue in the positive control group showed ulcer in the dorsum surface with inflammatory cells, hyperplasia of the mucosa membrane around the ulcer (acanthosis) with increase of dentition, vacuolar degeneration of prickle cell layer and increase mitotic activity of basal cell layer together with dermal proliferation.

Conclusion

Under the condition of the present study, PDT using nanocurcumin photosensitizer was effective in the treatment of OSCC regarding clinical, histological and gene expression of BCL2 and Caspase-3.

Autofluorescence Image-Guided Endoscopy in the Management of Upper Aerodigestive Tract Tumors

At this juncture, autofluorescence and narrow-band imaging have resurfaced in the medicine arena in parallel with current technology advancement. The emergence of newly developed optical instrumentation in addition to the discovery of new fluorescence biomolecules have contributed to a refined management of diseases and tumors, especially in the management of upper aerodigestive tract tumors. The advancement in multispectral imaging and micro-endoscopy has also escalated the trends further in the setting of the management of this tumor, in order to gain not only the best treatment outcomes but also facilitate early tumor diagnosis. This includes the usage of autofluorescence endoscopy for screening, diagnosis and treatment of this tumor. This is crucial, as microtumoral deposit at the periphery of the gross tumor can be only assessed via an enhanced endoscopy and even more precisely with autofluorescence endoscopic techniques. Overall, with this new technique, optimum management can be achieved for these patients. Hence, the treatment outcomes can be improved and patients are able to attain better prognosis and survival.

Identification of RNA-splicing factor Lsm12 as a novel tumor-associated gene and a potent biomarker in Oral Squamous Cell Carcinoma (OSCC)

Background

Oral squamous cell carcinoma (OSCC) is one of the common cancers worldwide. The lack of specific biomarkers and therapeutic targets leads to delayed diagnosis and hence the poor prognosis of OSCC patients. Thus, it is urgent to identify effective biomarkers and therapeutic targets for OSCC.

Methods

We established the golden hamster carcinogenic model of OSCC induced by 7,12-dimethylbenz(a) anthrancene (DMBA) and used mRNA microarrays to detect the differentially expressed genes (DEGs). DEGs were validated in OSCC clinical tissue microarrays using immunohistochemistry method. Whole transcriptome sequencing was performed to obtain an overview of biological functions of Lsm12. PCR assay and sequencing were employed to investigate the alternative splicing of genes regulated by Lsm12. Cell proliferation, colony formation, Transwell migration and invasion assay and in vivo tumor formation assay were performed to investigate the roles of Lsm12 and two transcript variants of USO1 in OSCC cells.

Results

Lsm12 was identified to be significantly up-regulated in the animal model of OSCC tumorigenesis, which was validated in the clinical OSCC samples. In the paired normal tissues, Lsm12 staining was negative (91%, 92/101) or weak, while in OSCC tissues, positive rate is 100% and strong staining spread over the whole tissues in 93 (93/101, 92%) cases. Lsm12 overexpression significantly promoted OSCC cell growth, colony formation, migration and invasion abilities, while Lsm12 knockdown showed the opposite trends on these phenotypes and obviously inhibited the tumor formation in vivo. Furthermore, Lsm12 overexpression caused the inclusion of USO1 exon 15 and Lsm12 knockdown induced exon 15 skipping. Exon 15-retained USO1 significantly promoted the malignant phenotypes of OSCC cells when compared with the exon 15-deleted USO1.

Conclusions

We identified Lsm12, a novel tumorigenesis-related gene, as an important regulator involved in OSCC tumorigenesis. Lsm12 is a novel RNA-splicing related gene and can regulate the alternative splicing of USO1 exon 15 which was associated closely with OSCC carcinogenesis. Our findings thus provide that Lsm12 might be a potent biomarker and potential therapeutic target for OSCC.

Depletion of PARP10 inhibits the growth and metastatic potential of oral squamous cell carcinoma

Background: Although poly (ADP-ribose) polymerase family member 10 (PARP10) has been implicated in the progression of multiple cancer types, its role in oral squamous cell carcinoma (OSCC) remains unknown. This study aimed to examine the function of PARP10 in OSCC and investigate the underlying mechanisms.

Methods: The expression of PARP10 in OSCC was investigated in OSCC patient cohorts. Kaplan-Meier curve analysis was performed to assess the association between PARP10 and prognosis in OSCC. Correlation between PARP10 expression and the related variables was analyzed by χ² test. CKK-8, transwell assay, western blot, immunohistochemistry, immunofluorescence, and bioinformatic analysis, were applied to clarify the role of PARP10 in OSCC.

Results: PARP10 was found to be markedly elevated in OSCC tissues. The upregulation of PARP10 predicted shorter overall survival and disease-specific survival and was significantly correlated with several malignant features. Moreover, depletion of PARP10 markedly inhibited the proliferation, migration, and invasion of OSCC cells, and promoted OSCC cell apoptosis, and resulted in alterations of relevant proteins. Furthermore, a positive correlation was observed between the expression of PARP10 and Ki67, PARP1, MMP2, and VEGF. In addition, depletion of PARP10 impaired the PI3K-AKT and MAPK signaling pathways.

Conclusion: PARP10 is involved in the progression of OSCC via regulation of PI3K-AKT and MAPK signaling pathways.

Machine learning in point-of-care automated classification of oral potentially malignant and malignant disorders: a systematic review and meta-analysis

Machine learning (ML) algorithms are becoming increasingly pervasive in the domains of medical diagnostics and prognostication, afforded by complex deep learning architectures that overcome the limitations of manual feature extraction. In this systematic review and meta-analysis, we provide an update on current progress of ML algorithms in point-of-care (POC) automated diagnostic classification systems for lesions of the oral cavity. Studies reporting performance metrics on ML algorithms used in automatic classification of oral regions of interest were identified and screened by 2 independent reviewers from 4 databases. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. 35 studies were suitable for qualitative synthesis, and 31 for quantitative analysis. Outcomes were assessed using a bivariate random-effects model following an assessment of bias and heterogeneity. 4 distinct methodologies were identified for POC diagnosis: (1) clinical photography; (2) optical imaging; (3) thermal imaging; (4) analysis of volatile organic compounds. Estimated AUROC across all studies was 0.935, and no difference in performance was identified between methodologies. We discuss the various classical and modern approaches to ML employed within identified studies, and highlight issues that will need to be addressed for implementation of automated classification systems in screening and early detection.

To Evaluate the Efficacy of Tissue Autofluorescence (Velscope) in the Visualization of Oral Premalignant and Malignant Lesions among High-Risk Population Aged 18 Years and Above in Haroli Block of Una, Himachal Pradesh

Introduction

Visually enhanced lesion scope (Velscope) that identifies reduction in tissue fluorescence in dysplasia can prove to be effective in screening for potentially malignant lesions. The objective of the present study was to evaluate the effectiveness of device that utilizes the principles of tissue autofluorescence (Velscope) in the detection of dysplastic and/or neoplastic changes in oral mucosal lesions using biopsy and histopathology as "gold standard."

Materials and Methods

Out of nine hundred fifty patients with suspicious oral mucosal lesions, 250 patients were subjected to conventional oral examination followed by Velscope examination. The autofluorescence characteristics of 250 patients were compared with the results of histopathology. Biopsies were obtained from all suspicious areas identified on examination. The sensitivity, specificity, positive and negative predictive values were calculated for Velscope examination.

Results

The Velscope examination showed sensitivity and specificity values of 75.00% (95% CI: 69.63%-80.37%) and 61.39% (95% CI: 55.35%-67.42%) respectively while the positive and negative predictive values were 31.58% (95% CI: 25.82%-37.34%) and 91.18% (95% CI: 87.66%-94.69%) respectively.

Conclusion

The definite diagnosis of the presence of dysplastic tissue changes in the oral lesions cannot be made alone with the Velscopic examination. The high number of false-positive results limits its efficiency as an adjunct despite its reasonable sensitivity. However, It can serve to alleviate patient anxiety regarding suspicious mucosal lesions in a general practice setting due to high negative predictive value. Also, a combined approach of Velscope examination and conventional oral examination may prove to be an effective diagnostic tool for early detection of malignant oral mucosal lesions.

Prognostic significance of a 4-lncRNA glycolysis-related signature in oral squamous cell carcinoma

BACKGROUND/PURPOSE

Oral squamous cell carcinoma (OSCC) is a highly malignant tumor, and the overall survival (OS) time of patients with OSCC varies considerably. This study aimed to identify reliable biomarkers for OSCC and construct a new prognostic signature, which may guide personalized precision treatment.

MATERIALS AND METHODS

Transcriptome array data of 317 patients with OSCC from The Cancer Genome Atlas Project (TCGA) cohort were retrospectively analyzed. Single-sample gene set enrichment analysis (ssGSEA) and univariate Cox regression were performed to identify the prognostic significance of the hallmarks of each tumor in OSCC. Subsequently, lncRNAs related to glycolysis were identified through co-expression analysis. A glycolysis-related prognostic signature was constructed by combining univariate Cox regression, least absolute shrinkage and selection operator (Lasso) regression, and multivariate Cox regression analyses. Additionally, the infiltration of immune cells in OSCC was evaluated based on data from ssGSEA and TIMER databases.

RESULTS

Glycolysis was identified as the main risk factor for OS in a variety of cancer hallmarks. The 4-lncRNA glycolysis prognostic signature could distinguish high and low-risk patients. This risk signature was found to be an independent prognostic risk factor for OSCC, showing good predictive power compared with other clinicopathological indicators. Immune correlation analysis showed that patients in the low-risk group exhibited higher levels of immune cell infiltration.

CONCLUSION

The novel 4-lncRNA prognostic signature can predict the clinical outcome of patients with OSCC well, and it is expected to become a promising prognostic biomarker as well as a potential therapeutic target in the future.

The PER1/HIF-1alpha negative feedback loop promotes ferroptosis and inhibits tumor progression in oral squamous cell carcinoma

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PER1 is negatively correlated with GPX4 and HIF-1α expression in OSCC tissue.

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PER1 promotes ferroptosis in OSCC cells in a HIF-1α-dependent manner.

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PER1 binds with HIF-1α to promote HIF-1α degradation.

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HIF-1α binds to the PER1 promoter to inhibit PER1 transcription.

Current studies have proven that the decreased expression of the core circadian clock gene Period 1 (PER1) is closely related to the occurrence and progression of multiple malignant tumors, including oral squamous cell carcinoma (OSCC). But the mechanism involved is largely unknown. In this study, we found that PER1 was negatively correlated with the expression of the key ferroptosis-regulated proteins glutathione peroxidase (GPX4) and hypoxia inducible factor-1alpha (HIF-1α) in OSCC tissues. The expression of the ferroptosis related proteins GPX4, solute carrier family 7 member 11 (SLC7A11) and transferrin receptor (TFRC) and the levels of glutathione (GSH), malondialdehyde (MDA), reactive oxygen species (ROS) and Fe²⁺ were detected in OSCC cells with overexpression or silencing of PER1. Mitochondrial morphology changes were observed. We found that PER1 promotes ferroptosis depending on HIF-1α in OSCC cells. In vivo tumorigenicity assays proved that PER1 overexpression inhibits HIF-1α, promotes ferroptosis and suppresses OSCC growth. Mechanistically, coimmunoprecipitation and cycloheximide tracking assays proved that PER1 binds to HIF-1α to promote HIF-1α protein degradation. ChIP and dual luciferase reporter assays proved that HIF-1α binds to the PER1 promoter leading to feedback inhibition of PER1 transcription. Our findings suggest that targeting the PER1/HIF-1α negative feedback loop may provide a new strategy for OSCC treatment.

Developing an Algorithm for Discriminating Oral Cancerous and Normal Tissues Using Raman Spectroscopy

The aim of this study was to investigate the clinical potential of Raman spectroscopy (RS) in detecting oral squamous cell carcinoma (OSCC) in tumor and healthy tissues in surgical resection specimens during surgery. Raman experiments were performed on cryopreserved specimens from patients with OSCC. Univariate and multivariate analysis was performed based on the fingerprint region (700-1800 cm-1) of the Raman spectra. One hundred thirty-one ex-vivo Raman experiments were performed on 131 surgical resection specimens obtained from 67 patients. The principal component analysis (PCA) and partial least square (PLS) methods with linear discriminant analysis (LDA) were applied on an independent validation dataset. Both models were able to differentiate between the tissue types, but PLS-LDA showed 100% accuracy, sensitivity, and specificity. In this study, Raman measurements of fresh resection tissue specimens demonstrated that OSCC had significantly higher nucleic acid, protein, and several amino acid contents than adjacent healthy tissues. The specific spectral information obtained in this study can be used to develop an in vivo Raman spectroscopic method for the tumor-free resection boundary during surgery.

Protein Cargo of Salivary Small Extracellular Vesicles as Potential Functional Signature of Oral Squamous Cell Carcinoma

The early diagnosis of oral squamous cell carcinoma (OSCC) is still an investigative challenge. Saliva has been proposed as an ideal diagnostic medium for biomarker detection by mean of liquid biopsy technique. The aim of this pilot study was to apply proteomic and bioinformatic strategies to determine the potential use of saliva small extracellular vesicles (S/SEVs) as a potential tumor biomarker source. Among the twenty-three enrolled patients, 5 were free from diseases (OSCC_FREE), 6 were with OSCC without lymph node metastasis (OSCC_NLNM), and 12 were with OSCC and lymph node metastasis (OSCC_LNM). The S/SEVs from patients of each group were pooled and properly characterized before performing their quantitative proteome comparison based on the SWATH_MS (Sequential Window Acquisition of all Theoretical Mass Spectra) method. The analysis resulted in quantitative information for 365 proteins differentially characterizing the S/SEVs of analyzed clinical conditions. Bioinformatic analysis of the proteomic data highlighted that each S/SEV group was associated with a specific cluster of enriched functional network terms. Our results highlighted that protein cargo of salivary small extracellular vesicles defines a functional signature, thus having potential value as novel predict biomarkers for OSCC.

Diagnostic Concordance between Optical Coherence Tomography and Histological Investigations for Immune-Mediated Desquamative Gingivitis: Observational Study

Desquamative gingivitis (DG) denotes a heterogeneous immune-mediated disease for which early diagnosis represents a great challenge. The main aim of this study is to validate diagnostic concordance between specific Optical Coherence Tomography (OTC) patterns for DG related to oral Lichen Planus (OLP), Pemphigus Vulgaris (PV), and Mucous Membrane Pemphigoid (MMP) and definitive histological diagnosis. Forty-three patients with suspected immune-mediated DGs, were progressively recruited. Before biopsy, an OCT preliminary evaluation was performed using specific pre-determined OCT diagnostic patterns (i.e., morphology and localization of blisters, status of the basal membrane, epithelial thickness, presence/absence of acantholytic cells into blister and/or inflammatory infiltrate) related to OLP, PV and MMP. After histological confirmation, OCT and histological diagnoses were compared. Using pre-determined patterns, OCT diagnoses of DGs were: 22 (51%) OLP, of which 11 (26%) were with the bullous variant, 4 (9%) PV and 6 (14%) MMP. The same diagnoses were found by histological investigations (with the main OCT discriminatory potential for the bullous variant of OLP). The concordance between the two diagnostic methods was confirmed by the Fisher exact test (p-value < 0.01). These specific OCT patterns show a diagnostic reliability in 100% of the cases investigated, suggesting their accuracy to support the complex diagnosis and management of immune-mediated DGs.

Bimodal multispectral imaging system with cloud-based machine learning algorithm for real-time screening and detection of oral potentially malignant lesions and biopsy guidance

SIGNIFICANCE

Screening and early detection of oral potentially malignant lesions (OPMLs) are of great significance in reducing the mortality rates associated with head and neck malignancies. Intra-oral multispectral optical imaging of tissues in conjunction with cloud-based machine learning (CBML) can be used to detect oral precancers at the point-of-care (POC) and guide the clinician to the most malignant site for biopsy.

AIM

Develop a bimodal multispectral imaging system (BMIS) combining tissue autofluorescence and diffuse reflectance (DR) for mapping changes in oxygenated hemoglobin (HbO2) absorption in the oral mucosa, quantifying tissue abnormalities, and guiding biopsies.

APPROACH

The hand-held widefield BMIS consisting of LEDs emitting at 405, 545, 575, and 610 nm, 5MPx monochrome camera, and proprietary Windows-based software was developed for image capture, processing, and analytics. The DR image ratio (R610/R545) was compared with pathologic classification to develop a CBML algorithm for real-time assessment of tissue status at the POC.

RESULTS

Sensitivity of 97.5% and specificity of 92.5% were achieved for discrimination of OPML from patient normal in 40 sites, whereas 82% sensitivity and 96.6% specificity were obtained for discrimination of abnormal (OPML + SCC) in 89 sites. Site-specific algorithms derived for buccal mucosa (27 sites) showed improved sensitivity and specificity of 96.3% for discrimination of OPML from normal.

CONCLUSIONS

Assessment of oral cancer risk is possible by mapping of HbO2 absorption in tissues, and the BMIS system developed appears to be suitable for biopsy guidance and early detection of oral cancers.

Overview of oral cavity squamous cell carcinoma: Risk factors, mechanisms, and diagnostics

Oral cavity squamous cell carcinoma (OCSCC) is the most common malignancy of the oral cavity. The substantial risk factors for OCSCC are the consumption of tobacco products, alcohol, betel quid, areca nut, and genetic alteration. However, technological advancements have occurred in treatment, but the survival decreases with late diagnosis; therefore, new methods are continuously being investigated for treatment. In addition, the rate of secondary tumor formation is 3-7% yearly, which is incomparable to other malignancies and can lead to the disease reoccurrence. Oral cavity cancer (OCC) arises from genetic alterations, and a complete understanding of the molecular mechanism involved in OCC is essential to develop targeted treatments. This review aims to update the researcher on oral cavity cancer, risk factors, genetic alterations, molecular mechanism, classification, diagnostic approaches, and treatment.

Current Insights into Oral Cancer Diagnostics

Oral cancer is one of the most common head and neck malignancies and has an overall 5-year survival rate that remains below 50%. Oral cancer is generally preceded by oral potentially malignant disorders (OPMDs) but determining the risk of OPMD progressing to cancer remains a difficult task. Several diagnostic technologies have been developed to facilitate the detection of OPMD and oral cancer, and some of these have been translated into regulatory-approved in vitro diagnostic systems or medical devices. Furthermore, the rapid development of novel biomarkers, electronic systems, and artificial intelligence may help to develop a new era where OPMD and oral cancer are detected at an early stage. To date, a visual oral examination remains the routine first-line method of identifying oral lesions; however, this method has certain limitations and as a result, patients are either diagnosed when their cancer reaches a severe stage or a high-risk patient with OPMD is misdiagnosed and left untreated. The purpose of this article is to review the currently available diagnostic methods for oral cancer as well as possible future applications of novel promising technologies to oral cancer diagnosis. This will potentially increase diagnostic options and improve our ability to effectively diagnose and treat oral cancerous-related lesions.

Simulations of fluorescence imaging in the oral cavity

We describe an end-to-end image systems simulation that models a device capable of measuring fluorescence in the oral cavity. Our software includes a 3D model of the oral cavity and excitation-emission matrices of endogenous fluorophores that predict the spectral radiance of oral mucosal tissue. The predicted radiance is transformed by a model of the optics and image sensor to generate expected sensor image values. We compare simulated and real camera data from tongues in healthy individuals and show that the camera sensor chromaticity values can be used to quantify the fluorescence from porphyrins relative to the bulk fluorescence from multiple fluorophores (elastin, NADH, FAD, and collagen). Validation of the simulations supports the use of soft-prototyping in guiding system design for fluorescence imaging.

Identification of Salivary Proteomic Biomarkers for Oral Cancer Screening

BACKGROUND/AIM

The current study aimed to identify biomarkers for differentiating between patients with oral cancer (OC) and healthy controls (HCs) on the basis of the comprehensive proteomic analyses of saliva samples by using liquid chromatography-mass spectrometry (LC-MS/MS).

PATIENTS AND METHODS

Unstimulated saliva samples were collected from 39 patients with OC and from 31 HCs. Proteins in the saliva were comprehensively analyzed using LC-MS/MS. To differentiate between patients with OC and HCs, a multiple logistic regression model was developed for evaluating the discriminatory ability of a combination of multiple markers.

RESULTS

A total of 23 proteins were significantly differentially expressed between the patients with OC and the HCs. Six out of the 23 proteins, namely α-2-macroglobulin-like protein 1, cornulin, hemoglobin subunit β, Ig k chain V-II region Vk167, kininogen-1 and transmembrane protease serine 11D, were selected using the forward-selection method and applied to the multiple logistic regression model. The area under the curve for discriminating between patients with OC and HCs was 0.957 when the combination of the six metabolites was used (95% confidence interval=0.915-0.998; p<0.001). Furthermore, these candidate proteins did not show a stage-specific difference.

CONCLUSION

The results of the current study showed that six salivary proteins are potential non-invasive biomarkers for OC screening.

Noninvasive in vivo imaging of oral mucosa: state-of-the-art

Technological development has interested most of the dentistry's branches leading to the use of other medical technologies non previously involved in dental practice. This study aims to evaluate the potential role of non-invasive imaging techniques in oral pathology workflow. Optical coherence tomography has been described by several authors as a promising aid for differential diagnosis of autoimmune diseases and to detect epithelial subversion of the oral mucosa before the clinical manifestation of oral mucositis. High-frequency ultrasound offers the chance to assess lesional dimensions both in benign and malignant lesions with a high dimensional reliability compared with histopathology. Reflectance confocal microscopy seems to be helpful in the early detection of cytological changes due to its high resolution, suggesting a more interesting role in the analysis of malignant lesions. The study presented highlighted the potential role of noninvasive in vivo imaging although further studies are needed for the further validation of these techniques.

Noninvasive Imaging Methods to Improve the Diagnosis of Oral Carcinoma and Its Precursors: State of the Art and Proposal of a Three-Step Diagnostic Process

Simple Summary

Oral squamous cell carcinoma (OSCC) accounts for 90–95% of malignant tumors of the lip and oral cavity and is associated with high mortality in the advanced stages. Early diagnosis is a challenge for oral pathologists and dentists, due to the ambiguous appearance of early OSCC, which is often misdiagnosed, mistreated, and associated with diagnostic delay. The gold standards for OSCC diagnosis are biopsy and histopathological assessment, but these procedures are invasive and time-consuming. Adjunctive noninvasive techniques allow the definition of the malignant features of a suspicious lesion in real time and noninvasively, thus improving the diagnostic procedure. The present review aimed to focus on some of the main promising noninvasive imaging techniques, to highlight their perspective adoption in a three-step diagnosis, which is idealistically faster and better, as well as enables the patient’s compliance.

Abstract

Oral squamous cell carcinoma (OSCC) is the most prevalent form of cancer of lips and oral cavity, and its diagnostic delay, caused by misdiagnosis at the early stages, is responsible for high mortality ratios. Biopsy and histopathological assessment are the gold standards for OSCC diagnosis, but they are time-consuming, invasive, and do not always enable the patient’s compliance, mainly in cases of follow-up with the need for more biopsies. The use of adjunctive noninvasive imaging techniques improves the diagnostic approach, making it faster and better accepted by patients. The present review aims to focus on the most consolidated diagnostic techniques, such as vital staining and tissue autofluorescence, and to report the potential role of some of the most promising innovative techniques, such as narrow-band imaging, high-frequency ultrasounds, optical coherence tomography, and in vivo confocal microscopy. According to their contribution to OSCC diagnosis, an ideal three-step diagnostic procedure is proposed, to make the diagnostic path faster, better, and more accurate.

Plasma-Derived Exosomal microRNA-130a Serves as a Noninvasive Biomarker for Diagnosis and Prognosis of Oral Squamous Cell Carcinoma

Exosomal microRNAs (miRNAs) are considered as potential stable biomarkers in many types of human cancer, but investigations of plasma-derived exosomal miRNAs in oral squamous cell carcinoma (OSCC) are still lacking. The aim of this study is to evaluate the diagnostic and prognostic values of exosomal miR-130a in OSCC patients. Exosomes were isolated from plasma samples which were collected from 184 OSCC patients before surgery and 196 healthy individuals. Primary OSCC and paired adjacent noncancerous tissues were also obtained from 47 OSCC patients. The expression levels of miR-130a were analyzed by quantitative real-time PCR (qRT-PCR). Our results showed that the expression levels of exosomal miR-130a were significantly higher in OSCC patients than those of the healthy controls (p < 0.0001). Also, the expression of miR-130a was also significantly upregulated in OSCC tissues compared with paired adjacent noncancerous tissues (p < 0.0001). A significant positive correlation was found between exosomal miR-130a and tissue miR-130a levels. Receiver operating characteristic (ROC) analyses yielded an AUC value of 0.812 in discriminating OSCC patients from healthy controls. Furthermore, high levels of exosomal miR-130a were associated with the late T-stage (p=0.024), advanced TNM stage (p=0.003), and poorly differentiated OSCC (p=0.013). Patients with high exosomal miR-130a expression had significantly worse 3-year overall survival (OS) and recurrence-free survival (RFS). Multivariate analysis indicated that exosomal miR-130a was an independent prognostic factor for OS (p=0.001) and RFS (p=0.003). Our results suggest that exosomal miR-130a may serve as a promising diagnostic and prognostic biomarker for OSCC patients.

Recent advances in point-of-care diagnostics for oral cancer

Early-stage diagnosis is a crucial step in reducing the mortality rate in oral cancer cases. Point-of-care (POC) devices for oral cancer diagnosis hold great future potential in improving the survival rates as well as the quality of life of oral cancer patients. The conventional oral examination followed by needle biopsy and histopathological analysis have limited diagnostic accuracy. Besides, it involves patient discomfort and is not feasible in resource-limited settings. POC detection of biomarkers and diagnostic adjuncts has emerged as non- or minimally invasive tools for the diagnosis of oral cancer at an early stage. Various biosensors have been developed for the rapid detection of oral cancer biomarkers at the point-of-care. Several optical imaging methods have also been employed as adjuncts to detect alterations in oral tissue indicative of malignancy. This review summarizes the different POC platforms developed for the detection of oral cancer biomarkers, along with various POC imaging and cytological adjuncts that aid in oral cancer diagnosis, especially in low resource settings. Various immunosensors and nucleic acid biosensors developed to detect oral cancer biomarkers are summarized with examples. The different imaging methods used to detect oral tissue malignancy are also discussed herein. Additionally, the currently available commercial devices used as adjuncts in the POC detection of oral cancer are emphasized along with their characteristics. Finally, we discuss the limitations and challenges that persist in translating the developed POC techniques in the clinical settings for oral cancer diagnosis, along with future perspectives.

Patient perception after oral biopsies: an observational outpatient study

OBJECTIVE

The aim of this study was to evaluate the postoperative course in patients undergoing oral mucosal biopsies, considering clinical and patient's perception variables potentially correlated to poor healing.

SUBJECTS AND METHODS

Eighty patients underwent oral biopsies. All the variables connected with the surgery were recorded, and the harvested volume was calculated through image software (ImageJ, NIH, Betesda, USA). To evaluate the postoperative discomfort, the OHIP-14 and the numeric rating scale of pain (NRS) were administered at 6 h, 7 days and 21 days after biopsy.

RESULTS

Six hours after the biopsy, 22 (OHIP-14 ≥ 20) and 24 (NRS ≥ 4) patients experienced a troublesome or painful healing, respectively. A significant statistical correlation between poor healing and high scores of NRS and OHIP was detected (Pearson's correlation test p < 0.05). Higher values of OHIP-14 were correlated to the type of lesion (OR = 1.165; p < 0.05), whereas high values of NRS were correlated to the use of systemic drugs (p < 0.05). No surgical variable had a significant statistical correlation with any of the outcomes.

CONCLUSIONS

The clinical evaluation was correlated with the patient's perception of pain and discomfort. This finding could be suggestive of the fact that wound healing can be reliably monitored with the help of these tools.

CLINICAL RELEVANCE

Patient perception can be a predictor of the healing of biopsied tissues.

[Autofluorescence visualization of the oral malignant lesions]

OBJECTIVE

The aim of the present paper was to observe the main features of the autofluorescence emission of the oral epithelial carcinomas.

MATERIAL AND METHODS

The study included four patients aged 38-61 years with the oral epithelial carcinomas located at a cheek, a floor of the mouth, a bottom lip. All the diagnoses were later confirmed histologically. The oral cavity was inspected traditionally and then using autofluorescence visualization. For autofluorescence emission excitation we used the home-made LED-based device emitting near 400 nm.

RESULTS

The tissue autofluorescence was visualized in the broad and narrow spectral bands. In comparison with the healthy mucosa the pathological lesions showed the large losses of the green autofluorescence emissions ("dark sport effect") which have been visualized at both spectral bands. The visualization in the broad spectral band allowed to reveal that three lesions had the local sites of red fluorescence of the endogenous porphyrins traditionally connected with the local inflammation.

CONCLUSION

Autofluorescence stomatoscopy is not only important but also mandatory for oncological screening and should be widely used as the additional method of oral mucosa examination in the common dental practice.

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

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

Multimodal widefield fluorescence imaging with nonlinear optical microscopy workflow for noninvasive oral epithelial neoplasia detection: a preclinical study

SIGNIFICANCE

Early detection of epithelial cancers and precancers/neoplasia in the presence of benign lesions is challenging due to the lack of robust in vivo imaging and biopsy guidance techniques. Label-free nonlinear optical microscopy (NLOM) has shown promise for optical biopsy through the detection of cellular and extracellular signatures of neoplasia. Although in vivo microscopy techniques continue to be developed, the surface area imaged in microscopy is limited by the field of view. FDA-approved widefield fluorescence (WF) imaging systems that capture autofluorescence signatures of neoplasia provide molecular information at large fields of view, which may complement the cytologic and architectural information provided by NLOM.

AIM

A multimodal imaging approach with high-sensitivity WF and high-resolution NLOM was investigated to identify and distinguish image-based features of neoplasia from normal and benign lesions.

APPROACH

In vivo label-free WF imaging and NLOM was performed in preclinical hamster models of oral neoplasia and inflammation. Analyses of WF imaging, NLOM imaging, and dual modality (WF combined with NLOM) were performed.

RESULTS

WF imaging showed increased red-to-green autofluorescence ratio in neoplasia compared to inflammation and normal oral mucosa (p  <  0.01). In vivo assessment of the mucosal tissue with NLOM revealed subsurface cytologic (nuclear pleomorphism) and architectural (remodeling of extracellular matrix) atypia in histologically confirmed neoplastic tissue, which were not observed in inflammation or normal mucosa. Univariate and multivariate statistical analysis of macroscopic and microscopic image-based features indicated improved performance (94% sensitivity and 97% specificity) of a multiscale approach over WF alone, even in the presence of benign lesions (inflammation), a common confounding factor in diagnostics.

CONCLUSIONS

A multimodal imaging approach integrating strengths from WF and NLOM may be beneficial in identifying oral neoplasia. Our study could guide future studies on human oral neoplasia to further evaluate merits and limitations of multimodal workflows and inform the development of multiscale clinical imaging systems.

Spectroscopic Studies on the Biomolecular Recognition of Toluidine Blue: Key Information Towards Development of a Non-Contact, Non-Invasive Device for Oral Cancer Detection

Molecular interaction of aromatic dyes with biological macromolecules are important for the development of minimally invasive disease diagnostic biotechnologies. In the present work, we have used Toluidine Blue (TB) as a model dye, which is a well-known staining agent for the diagnosis of oral cancer and have studied the interaction of various biological macromolecules (protein and DNA) with the dye at different pH. Our spectroscopic studies confirm that TB interacts with Human Serum Albumin (HSA), a model protein at very high pH conditions which is very hard to achieve physiologically. On the other hand, TB significantly interacts with the DNA at physiological pH value (7.4). Our molecular studies strengthen the understanding of the Toluidine Blue staining of cancer cells, where the relative ratio of the nucleic acids is higher than the normal intracellular content. We have also developed a non-invasive, non-contact spectroscopic technique to explore the possibility of quantitatively detecting oral cancer by exploiting the interaction of TB with DNA. We have also reported development of a prototype named "Oral-O-Scope" for the detection of Oral cancer and have carried out human studies using the prototype.

Non-Invasive Early Detection of Oral Cancers Using Fluorescence Visualization with Optical Instruments

Simple Summary

Oral cancer has a high mortality rate. Then, oral cancer screening is needed for early detection and treatment. Fluorescence visualization is non-invasive, convenient, and in real-time, and examinations can be repeated. Our study aimed to show the usefulness of oral cancer screening with fluorescence visualization. A total of 502 patients were performed using fluorescence visualization that was analyzed using subjective and objective evaluation. Results of this study, subjective evaluation for detection oral cancer was high sensitivity and low specificity, while objective evaluation using imaging processing analysis was high sensitivity and high specificity. Therefore, oral cancer screening using fluorescence visualization is useful for the detection of oral cancer. The widespread use of this screening can reduce the mortality rate of oral cancer.

Abstract

Background: Oral cancer screening is important for early detection and early treatment, which help improve survival rates. Biopsy is the gold standard for a definitive diagnosis but is invasive and painful, while fluorescence visualization is non-invasive, convenient, and real-time, and examinations can be repeated using optical instruments. The purpose of this study was to clarify the usefulness of fluorescence visualization in oral cancer screening. Methods: A total of 502 patients, who were examined using fluorescence visualization with optical instruments in our hospitals between 2014 and 2019, were enrolled in this study. The final diagnosis was performed by pathological examination. Fluorescence visualization was analyzed using subjective and objective evaluations. Results: Subjective evaluations for detecting oral cancer offered 96.8% sensitivity and 48.4% specificity. Regarding the objective evaluations, sensitivity and specificity were 43.7% and 84.6% for mean green value, 55.2% and 67.0% for median green value, 82.0% and 44.2% for coefficient of variation of value, 59.6% and 45.3% for skewness, and 85.1% and 75.8% for value ratio. For the sub-analysis of oral cancer, all factors on objective and subjective evaluation showed no significant difference. Conclusions: Fluorescence visualization with subjective and objective evaluation is useful for oral cancer screening.

Italian Response to Coronavirus Pandemic in Dental Care Access: The DeCADE Study

The aim of the study was to evaluate the impact of the coronavirus pandemic on the willingness, anxiety and concerns of Italian people on undergoing dental appointments. An anonymous survey was posted online on social media on 11 May 2020 and was completed by 1003 respondents in one week. Multiple correspondence analysis and multiple logistic regression were used to evaluate the association between socio-demographic characteristics, dental care access, contagion fear of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), trust in dentists regarding sanitization procedures and perception of the impact of the risk of contagion on dental care. Subjects with a high level of education, attending public dental offices and that are used to go to dental offices for urgent care would not feel comfortable in undergoing a dental appointment and would prefer to postpone or cancel dental visits, waiting for a decrease in the number of the contagions. Moreover, the risk of canceling or postponing the appointment at the dentist was 1.59 times greater in those who claimed to be strongly influenced by SARS-CoV-2. Fear of coronavirus disease (COVID-19), new cases decrease and the not urgent nature of dental visits influenced more than the lowered income household on upcoming or resuming dental appointments. In the next months, despite the forecasted economic crisis caused by coronavirus pandemic, fear and anxiety generated by the spread of the virus will impact more than the lowered familiar income with regards to access to dental care.

Theoretical Background to Automated Diagnosing of Oral Leukoplakia: A Preliminary Report

Oral leukoplakia represents the most common oral potentially malignant disorder, so early diagnosis of leukoplakia is important. The aim of this study is to propose an effective texture analysis algorithm for oral leukoplakia diagnosis. Thirty-five patients affected by leukoplakia were included in this study. Intraoral photography of normal oral mucosa and leukoplakia were taken and processed for texture analysis. Two features of texture, run length matrix and co-occurrence matrix, were analyzed. Difference was checked by ANOVA. Factor analysis and classification by the artificial neural network were performed. Results revealed easy possible differentiation leukoplakia from normal mucosa (p < 0.05). Neural network discrimination shows full leukoplakia recognition (sensitivity 100%) and specificity 97%. This objective analysis in the neural network revealed that involving 3 textural features into optical analysis of the oral mucosa leads to proper diagnosis of leukoplakia. Application of texture analysis for leukoplakia is a promising diagnostic method.

The Potential of Phytochemicals in Oral Cancer Prevention and Therapy: A Review of the Evidence

The etiological factors of oral cancer are complex including drinking alcohol, smoking tobacco, betel quid chewing, human papillomavirus infection, and nutritional deficiencies. Understanding the molecular mechanism of oral cancer is vital. The traditional treatment for patients with oral squamous cell carcinoma (e.g., surgery, radiotherapy, and chemotherapy) and targeted molecular therapy still have numerous shortcomings. In recent years, the use of phytochemical factors to prevent or treat cancer has received increasing attention. These phytochemicals have little or no toxicity against healthy tissues and are thus ideal chemopreventive agents. However, phytochemicals usually have low water solubility, low bioavailability, and insufficient targeting which limit therapeutic use. Numerous studies have investigated the development of phytochemical delivery systems to address these problems. The present article provides an overview of oral cancer including the etiological factors, diagnosis, and traditional therapy. Furthermore, the classification, dietary sources, anticancer bioactivity, delivery system improvements, and molecular mechanisms against oral cancer of phytochemicals are also discussed in this review.

Adenovirus-mediated overexpression of interleukin-21 regulates the development of oral squamous cell carcinoma in vitro

Interleukin-21 (IL-21) is an important cytokine that is currently being investigated for its potential use in tumor immunotherapy in the future. In tumor cells, IL-21 stimulates the immune response by increasing the cytotoxic activity of natural killer cells, B cells and CD8⁺ T cells, which in turn induces the apoptosis of tumor cells. The therapeutic effects of IL-21 have been investigated in several types of disease and numerous clinical trials are in progress. The aim of the present study was to determine the role of IL-21 in oral squamous cell carcinoma (OSCC) in vitro. IL-21 expression was detected in OSCC tissues via RT-qPCR, western blotting and immunohistochemistry analyses. The results demonstrated that IL-21 protein expression decreased in OSCC tissues. IL-21 was overexpressed using adenovirus in CAL-27 cells. The Cell Counting Kit-8 assay demonstrated that overexpression of IL-21 inhibited cell proliferation. Furthermore, overexpression of IL-21 inhibited cell migration, detected by the wound healing assay, and promoted cell apoptosis, detected by TUNEL staining and flow cytometry analysis. The results demonstrated that overexpression of IL-21 inhibited activation of the JNK signaling pathway. In conclusion, the findings of the present study suggest that IL-21 may function as a potent antitumor agent in OSCC.

Dental Public Health Landscape: Challenges, Technological Innovation and Opportunities in the 21st Century and COVID-19 Pandemic

In response to the 2008 economic and financial crisis and to its effects on healthcare systems, dental care has become unaffordable for many people, and a huge number of patients worldwide are avoiding or skipping necessary dental treatments [...].