Rising incidence of oral tongue cancer among white men and women in the United States, 1973-2012

The REASON score: an epigenetic and clinicopathologic score to predict risk of poor survival in patients with early stage oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a capricious cancer with poor survival rates, even for early-stage patients. There is a pressing need to develop more precise risk assessment methods to appropriately tailor clinical treatment. Genome-wide association studies have not produced a viable biomarker. However, these studies are limited by using heterogeneous cohorts, not focusing on methylation although OSCC is a heavily epigenetically-regulated cancer, and not combining molecular data with clinicopathologic data for risk prediction. In this study we focused on early-stage (I/II) OSCC and created a risk score called the REASON score, which combines clinicopathologic characteristics with a 12-gene methylation signature, to predict the risk of 5-year mortality.

METHODS

We combined data from an internal cohort (n = 515) and The Cancer Genome Atlas (TCGA) cohort (n = 58). We collected clinicopathologic data from both cohorts to derive the non-molecular portion of the REASON score. We then analyzed the TCGA cohort DNA methylation data to derive the molecular portion of the risk score.

RESULTS

5-year disease specific survival was 63% for the internal cohort and 86% for the TCGA cohort. The clinicopathologic features with the highest predictive ability among the two the cohorts were age, race, sex, tobacco use, alcohol use, histologic grade, stage, perineural invasion (PNI), lymphovascular invasion (LVI), and margin status. This panel of 10 non-molecular features predicted 5-year mortality risk with a concordance (c)-index = 0.67. Our molecular panel consisted of a 12-gene methylation signature (i.e., HORMAD2, MYLK, GPR133, SOX8, TRPA1, ABCA2, HGFAC, MCPH1, WDR86, CACNA1H, RNF216, CCNJL), which had the most significant differential methylation between patients who survived vs. died by 5 years. All 12 genes have already been linked to survival in other cancers. Of the genes, only SOX8 was previously associated with OSCC; our study was the first to link the remaining 11 genes to OSCC survival. The combined molecular and non-molecular panel formed the REASON score, which predicted risk of death with a c-index = 0.915.

CONCLUSIONS

The REASON score is a promising biomarker to predict risk of mortality in early-stage OSCC patients. Validation of the REASON score in a larger independent cohort is warranted.

Glaucocalyxin A induces apoptosis and autophagy in tongue squamous cell carcinoma cells by regulating ROS

PURPOSE

Tongue squamous cell carcinoma (TSCC) is the most common highly invasive oral cancer. Glaucocalyxin A (GLA) is a diterpenoid component isolated from Rabdosia japonica var. with anti-bacterial and anti-cancer biological properties. However, the role of GLA in human TSCC remains uncertain. The aim of this paper was to investigate the anti-cancer effect of GLA on TSCC cells as well as its underlying mechanism.

METHODS

Cell viability and growth were analyzed by CCK-8 assay and colony formation, respectively. DAPI staining and flow cytometry assay were used to detect the cell apoptosis. Lysotracker Red staining was used to observe the lysosomes and autolysosomes of TSCC cells. ROS fluorescent probe was used to test the intracellular ROS levels. Western blotting was used to detect the expression levels of apoptosis- and autophagy-related proteins.

RESULTS

GLA inhibits the cell viability and growth in TSCC cells. GLA induces TSCC cells apoptosis, autophagy and ROS production in a time- and concentration-dependent manner. In addition, GLA inhibits the viability of TSCC cells by inducing intracellular ROS production. Finally, GLA triggers ROS-dependent apoptosis and autophagy in TSCC cells.

CONCLUSION

Our results consistently suggested that GLA can induce apoptosis and autophagy in TSCC cells by generating ROS. GLA may serve as a promising therapeutic drug for overcoming TSCC.

PRKCA Overexpression Is Frequent in Young Oral Tongue Squamous Cell Carcinoma Patients and Is Associated with Poor Prognosis

Oral tongue squamous cell carcinomas (OTSCCs) have an increasing incidence in young patients, and many have an aggressive course of disease. The objective of this study was to identify candidate prognostic protein markers associated with early-onset OTSCC. We performed an exploratory screening for differential protein expression in younger (≤45 years) versus older (>45 years) OTSCC patients in The Cancer Genome Atlas (TCGA) cohort (n = 97). Expression of candidate markers was then validated in an independent Austrian OTSCC patient group (n = 34) by immunohistochemistry. Kaplan-Meier survival estimates were computed, and genomic and mRNA enrichment in silico analyses were performed. Overexpression of protein kinase C alpha (PRKCA) was significantly more frequent among young patients of both the TCGA (p = 0.0001) and the Austrian cohort (p = 0.02), associated with a negative anamnesis for alcohol consumption (p = 0.009) and tobacco smoking (p = 0.02) and poorer overall survival (univariate p = 0.02, multivariate p< 0.01). Within the young subgroup, both overall and disease-free survival were significantly decreased in patients with PRKCA overexpression (both p < 0.001). TCGA mRNA enrichment analysis revealed 332 mRNAs with significant differential expression in PRKCA-upregulated versus PRKCA-downregulated OTSCC (all FDR ≤ 0.01). Our findings suggest that PRKCA overexpression may be a hallmark of a novel molecular subtype of early-onset alcohol- and tobacco-negative high-risk OTSCC. Further analysis of the molecular PRKCA interactome may decipher the underlying mechanisms of carcinogenesis and clinicopathological behavior of PRKCA-overexpressing OTSCC.

Oral tongue squamous cell carcinomas in young patients according to their smoking status: a GETTEC study

BACKGROUND

Incidence of oral tongue squamous cell carcinoma (OTSCC) is increasing, especially in young adults, despite decreasing tobacco and alcohol consumption.

METHODS

This multicentric retrospective study of 185 young adults with OTSCC (median follow-up 43 months), investigated risk factors, tumour characteristics and oncological outcomes according to the smoking status.

RESULTS

Overall, 38% of patients were smokers (S). Non-smokers (NS) were significantly younger than S. Sex ratios were 1.1 for N and 1.8 for S. NS patients were less frequently cannabis or alcohol users than S, but were more likely to have a history of leukoplakia. Second primaries were observed in NS (4.4%) and in S (12.7%). Despite more frequent local relapse in NS (p = 0.018), there was no difference in diagnostic stage and overall survival between groups.

CONCLUSION

OTSCC affects differently young S and NS patients suggesting the existence of a specific clinical entity of OTSCC in non-smoking young adults.

Survival Outcomes in Oral Tongue Cancer: A Mono-Institutional Experience Focusing on Age

Objective

The prognostic role of age among patients affected by Oral Tongue Squamous Cell Carcinoma (OTSCC) is a topic of debate. Recent cohort studies have found that patients diagnosed at 40 years of age or younger have a better prognosis. The aim of this cohort study was to clarify whether age is an independent prognostic factor and discuss heterogeneity of outcomes by stage and treatments in different age groups.

Methods

We performed a study on 577 consecutive patients affected by primary tongue cancer and treated with surgery and adjuvant therapy according to stage, at European Institute of Oncology, IRCCS. Patients with age at diagnosis below 40 years totaled 109 (19%). Overall survival (OS), disease-free survival (DFS), tongue specific free survival (TSFS) and cause-specific survival (CSS) were compared by age groups. Multivariate Cox proportional hazards models were used to assess the independent role of age.

Results

The median follow-up time was 5.01 years (range 0–18.68) years with follow-up recorded up to February 2020. After adjustment for all the significant confounding and prognostic factors, age remained independently associated with OS and DSF (respectively, p = 0.002 and p = 0.02). In CSS and TSFS curves, the role of age seems less evident (respectively, p = 0.14 and p = 0.0.37). In the advanced stage sub-group (stages III–IV), age was significantly associated with OS and CSS with almost double increased risk of dying (OS) and dying from tongue cancer (CSS) in elderly compared to younger groups (OS: HR = 2.16 95%, CI: 1.33–3.51, p= 0.001; CSS: HR = 1.76 95%, CI: 1.03–3.01, p = 0.02, respectively). In our study, young patients were more likely to be treated with intensified therapies (glossectomies types III–V and adjuvant radio-chemotherapy). Age was found as a prognostic factor, independently of other significant factors and treatment. Also the T–N tract involved by disease and neutrophil-to-lymphocyte ratio ≥3 were independent prognostic factors.

Conclusions

Young age at diagnosis is associated with a better overall survival. Fewer younger people than older people died from tongue cancer in advanced stages.

A systematic review and meta-analysis of the prognostic role of age in oral tongue cancer

While evidence suggests an increasing incidence of tongue cancer in young adults, published findings regarding the prognostic role of age at diagnosis are inconsistent. We performed a meta-analysis of the literature to highlight key points that might help in understanding the association between age of oral tongue cancer patients at diagnosis and their prognosis. According to age at diagnosis, a systematic literature review of all published cohort studies assessing the recurrence risks and mortality associated with tongue cancer was conducted. We compared the risk estimates between patients aged >45 years and those aged <45 years at diagnosis. Random-effects models were used to calculate summary relative risk estimates (SRRs) according to different clinical outcomes and sources of between-study heterogeneity (I2 ) and bias. We included 31 independent cohort studies published between 1989 and 2019; these studies included a total of 28,288 patients. When risk estimations were not adjusted for confounders, no significant association was found between age at diagnosis and overall survival (OS). Conversely, after adjustment for confounders, older age at diagnosis was associated with a significantly increased risk of mortality. The difference between SRRs for adjusted and unadjusted estimates was significant (p < 0.01). Younger patients had a significantly higher risk of local recurrence. Younger patients with oral tongue cancer have better OS but a greater risk of recurrence than older patients. These findings should be validated in a large prospective cohort study which considers all confounders and prognostic factors.

Detection of human papillomavirus infection in laryngeal and hypopharyngeal carcinoma using droplet digital PCR and its correlation with prognosis

OBJECTIVE

To use droplet digital polymerase chain reaction (ddPCR) to detect human papillomavirus (HPV) infection in squamous cell carcinoma of the larynx and hypopharynx (SCCLHP) and to analyze its association with the prognosis of patients with HPV.

METHODS

We used ddPCR for HPV detection in 114 patients with SCCLHP; clinical data were collected, and the patients were followed-up for prognosis analysis. Univariate and multivariate Cox regression analyses were used to complete the analysis of risk factors. This clinical study was registered (clinical trial registration no. ChiCTR2000033032).

RESULT

Of the total cases, 15.79% (18/114) were HPV-positive and 8 (8/18, 44.4%) patients had tumors with HPV-16. There was a significant correlation between HPV-16 and the T classification and Tumor-Node-Metastasis (TNM) (P = 0.025 and 0.036, respectively). The 3-year overall survival rates in the HPV-positive and HPV-negative patients were 39.8% and 48.6% (P = 0.776), respectively. In the univariate analysis, HPV infection was not associated with the relative risk of progression (hazard ratio [HR] = 1.109, P = 0.778). Patients with laryngeal carcinoma (HR = 1.805, P = 0.037), no alcohol consumption (HR = 0.430, P = 0.009), well-differentiated tumors (HR = 2.570, p = 0.006), TNM I-II (HR = 2.482, P = 0.003), and no lymph node metastasis (HR = 2.615, P = 0.001) had better prognoses. In the multivariate analysis, tumor location (HR = 3.044, P = 0.001), alcohol consumption (HR = 0.474, P = 0.022), tumor differentiation (HR = 2.131, P = 0.030), and lymph node metastasis (HR = 4.179, P < 0.001) were independent predictors of better overall survival in SCCLHP.

CONCLUSION

ddPCR is an advanced technology that can accurately diagnose HPV infection with high specificity and sensitivity. The HPV infection rate in SCCLHP was low, and there was no significant difference in the prognosis of SCCLHP.

Personalized biomechanical tongue models based on diffusion-weighted MRI and validated using optical tracking of range of motion

For advanced tongue cancer, the choice between surgery and organ-sparing treatment is often dependent on the expected loss of tongue functionality after treatment. Biomechanical models might assist in this choice by simulating the post-treatment function loss. However, this function loss varies between patients and should, therefore, be predicted for each patient individually. In the present study, the goal was to better predict the postoperative range of motion (ROM) of the tongue by personalizing biomechanical models using diffusion-weighted MRI and constrained spherical deconvolution reconstructions of tongue muscle architecture. Diffusion-weighted MRI scans of ten healthy volunteers were obtained to reconstruct their tongue musculature, which were subsequently registered to a previously described population average or atlas. Using the displacement fields obtained from the registration, the segmented muscle fiber tracks from the atlas were morphed back to create personalized muscle fiber tracks. Finite element models were created from the fiber tracks of the atlas and those of the individual tongues. Via inverse simulation of a protruding, downward, left and right movement, the ROM of the tongue was predicted. This prediction was compared to the ROM measured with a 3D camera. It was demonstrated that biomechanical models with personalized muscles bundles are better in approaching the measured ROM than a generic model. However, to achieve this result a correction factor was needed to compensate for the small magnitude of motion of the model. Future versions of these models may have the potential to improve the estimation of function loss after treatment for advanced tongue cancer.

AG-9, an Elastin-Derived Peptide, Increases In Vitro Oral Tongue Carcinoma Cell Invasion, through an Increase in MMP-2 Secretion and MT1-MMP Expression, in a RPSA-Dependent Manner

Oral tongue squamous cell carcinoma is one of the most prevalent head and neck cancers. During tumor progression, elastin fragments are released in the tumor microenvironment. Among them, we previously identified a nonapeptide, AG-9, that stimulates melanoma progression in vivo in a mouse melanoma model. In the present paper, we studied AG-9 effect on tongue squamous cell carcinoma invasive properties. We demonstrated that AG-9 stimulates cell invasion in vitro in a modified Boyen chamber model. It increases MMP-2 secretion, analyzed by zymography and MT1-MMP expression, studied by Western blot. The stimulatory effect was mediated through Ribosomal Protein SA (RPSA) receptor binding as demonstrated by SiRNA experiments. The green tea-derived polyphenol, (−)-epigallocatechin-3-gallate (EGCG), was previously shown to bind RPSA. Molecular docking experiments were performed to compare the preferred areas of interaction of AG-9 and EGCG with RPSA and suggested overlapping areas. This was confirmed by competition assays. EGCG abolished AG-9-induced invasion, MMP-2 secretion, and MT1-MMP expression.

High expression of Notch2 drives tongue squamous cell carcinoma carcinogenesis

Tongue squamous cell carcinoma (TSCC) is one of the most common cancers in the oral cavity. Notch signaling is frequently dysregulated in cancer. However, the role of Notch2 in TSCC is not well understood. The aim of this study was to investigate the effect of abnormal expression of Notch2 in TSCC. The expression of Notch2 was tested in 47 pairs of tissues from tongue cancer and normal samples by using immunohistochemical staining. Tongue cancer cells were transfected with siRNA or plasmid. The proliferation of the cells was tested by the CCK8 assay and colony formation assay. Subcutaneous tumor model was established to observe tumor growth. Transwell assay was used to detect the changes of cell migration and invasion ability. A humanized anti-Notch2 antibody was used to TSCC cells. We found that Notch2 was upregulated in tongue carcinoma tissues. Knocking down the expression of Notch2 by siRNA in the TSCC cell lines decreased proliferation ability both in vitro and in vivo. In addition, migration and invasion abilities were inhibited by knockdown of Notch2 in the TSCC cells. However, overexpression of Notch2 increased tongue cancer cell proliferation, invasion and migration. The humanized anti-Notch2 antibody inhibited TSCC cell growth. The results indicated that Notch2 is an oncogene in tongue squamous cell carcinoma and may become the target of a new approach for treating TSCC.

Survival of Young Versus Old Patients With Oral Cavity Squamous Cell Carcinoma: A Meta-Analysis

OBJECTIVE/HYPOTHESIS

To assess whether young patients with oral cavity squamous cell carcinoma (OCSCC) demonstrate worse oncologic outcomes than older patients after definitive therapy.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A medical librarian composed a search strategy to identify relevant studies in Medline, Embase, Scopus, and other major databases (Prospero registration number CRD42019127974). Inclusion criteria were adults with histologically diagnosed OCSCC that underwent treatment, comparator groups with an age cutoff of 40 years old, and reported survival outcomes. Articles were excluded if they contained patients with oropharyngeal squamous cell carcinoma or patients treated for palliative intent. Overall survival hazard ratios were analyzed with a meta-analysis.

RESULTS

There were 23,382 patients with OCSCC that were treated with definitive therapy from 22 included studies. The pooled cohort contained 2,238 (10%) patients ≤40 years of age. Oral tongue was the most common subsite in both the younger (n = 1,961, 91%) and older (n = 18,047, 88%) cohorts. The majority of OCSCCs were either T1 or T2, representing 859 (80%) malignancies in younger patients and 8,126 (77%) malignancies in older patients. A meta-analysis of nine studies demonstrated that younger patients did not experience worse survival outcomes than older patients (hazard ratio = 0.97, 95% confidence interval = 0.66-1.41).

CONCLUSIONS

Young adults with OCSCC experienced similar oncologic outcomes as older patients with OCSCC after definitive treatment. Until compelling evidence demonstrates clinically relevant differences between these two cohorts, their approach to management should be similar. Future studies should consider comorbidities and using age 40 as a standard age cutoff to provide more uniform data moving forward. Laryngoscope, 131:1310-1319, 2021.

Prognostic outcomes of treatment naïve oral tongue squamous cell carcinoma (OTSCC): a comprehensive analysis of 14 years

OBJECTIVES

To analyze the factors predicting survival outcomes in treatment naïve oral tongue squamous cell carcinoma (OTSCC).

MATERIALS AND METHODS

A comprehensive review of 531 oral tongue carcinoma patients treated with upfront surgery followed by adjuvant radiotherapy or chemoradiotherapy was conducted from 2004-2018.

RESULTS

The mean age of presentation was 53 years (11-86) with a male to female ratio of 1.3:1. The associated risk factors were smoking (21%), betel nut (16%), naswar (9%) and alcohol (1%). Most of the cases were either well (45.1%) or moderately (46.2%) differentiated. Surgery was performed in 164 patients alone while 368 were treated with surgery in combination with adjuvant modalities. Overall (OS) and disease free survival (DFS) were 66 and 71%, respectively, with a median follow up of 2.5 years. Cox regression analysis showed nodal positivity, increased depth of invasion (DOI) and higher lymph node ratio (LNR) as significant prognosticators impacting OS and DSS.

CONCLUSION

Nodal volume, DOI and LNR are the most consistent predictors of poor outcome in OTSCC. Nodal positivity, depth of invasion > 5 mm and lymph node ratio > 0.04 adversely affect OS and DSS.

Genetic Mutations in Young Nonsmoking Patients With Oral Cavity Cancer: A Systematic Review

Objective

This investigation aims to review the known genetic mutations associated with oral cavity squamous cell carcinoma (OCSCC) in young adults with limited environmental risk factors (YLERs).

Data Sources

A comprehensive search strategy was designed to identify studies in MEDLINE (Ovid), Embase (Ovid), and Scopus from database inception to May 2017 that included adults ≤50 years of age with OCSCC and minimal tobacco use history (≤10 pack-years) who had their tumors genetically sequenced or mutational profiles analyzed.

Review Methods

Identified articles were screened by 2 reviewers. Quality of evidence was graded by the MINORS criteria for case-control studies; other studies were graded by assigning a level of evidence for gene mutation literature.

Results

Thirteen studies met our inclusion criteria, and 130 patients met our criteria for age and tobacco history. TP53 was the most commonly evaluated gene (10 of 13 studies) and the most frequently observed mutation. One study reported that nonsmokers had significantly fewer TP53 mutations, while 9 studies found no difference in the prevalence of TP53 mutations. No other mutations were found specific to this cohort.

Conclusions

TP53 mutations may occur at a similar rate in YLERs with OCSCC as compared with older patients or those with risk factors. However, few studies have aimed to characterize the genetic landscape of oral cavity tumors in this population, often with small sample sizes. Future studies are needed to explore unidentified genetic alterations leading to tumor susceptibility or alternative mechanisms of carcinogenesis.

The mutational landscape of early- and typical-onset oral tongue squamous cell carcinoma

BACKGROUND

The incidence of oral tongue squamous cell carcinoma (OTSCC) is increasing among younger birth cohorts. The etiology of early-onset OTSCC (diagnosed before the age of 50 years) and cancer driver genes remain largely unknown.

METHODS

The Sequencing Consortium of Oral Tongue Cancer was established through the pooling of somatic mutation data of oral tongue cancer specimens (n = 227 [107 early-onset cases]) from 7 studies and The Cancer Genome Atlas. Somatic mutations at microsatellite loci and Catalog of Somatic Mutations in Cancer mutation signatures were identified. Cancer driver genes were identified with the MutSigCV and WITER algorithms. Mutation comparisons between early- and typical-onset OTSCC were evaluated via linear regression with adjustments for patient-related factors.

RESULTS

Two novel driver genes (ATXN1 and CDC42EP1) and 5 previously reported driver genes (TP53, CDKN2A, CASP8, NOTCH1, and FAT1) were identified. Six recurrent mutations were identified, with 4 occurring in TP53. Early-onset OTSCC had significantly fewer nonsilent mutations even after adjustments for tobacco use. No associations of microsatellite locus mutations and mutation signatures with the age of OTSCC onset were observed.

CONCLUSIONS

This international, multicenter consortium is the largest study to characterize the somatic mutational landscape of OTSCC and the first to suggest differences by age of onset. This study validates multiple previously identified OTSCC driver genes and proposes 2 novel cancer driver genes. In analyses by age, early-onset OTSCC had a significantly smaller somatic mutational burden that was not explained by differences in tobacco use.

LAY SUMMARY

This study identifies 7 specific areas in the human genetic code that could be responsible for promoting the development of tongue cancer. Tongue cancer in young patients (under the age of 50 years) has fewer overall changes to the genetic code in comparison with tongue cancer in older patients, but the authors do not think that this is due to differences in smoking rates between the 2 groups. The cause of increasing cases of tongue cancer in young patients remains unclear.

Anti‑EpCAM monoclonal antibody exerts antitumor activity against oral squamous cell carcinomas

The epithelial cell adhesion molecule (EpCAM) is a calcium-independent, homophilic, intercellular adhesion factor classified as a transmembrane glycoprotein. In addition to cell adhesion, EpCAM also contributes to cell signaling, differentiation, proliferation, and migration. EpCAM is an essential factor in the carcinogenesis of numerous human cancers. In the present study, we developed and validated an anti-EpCAM monoclonal antibody (mAb), EpMab-16 (IgG_2a, kappa), by immunizing mice with EpCAM-overexpressing CHO-K1 cells. EpMab-16 specifically reacted with endogenous EpCAM in oral squamous cell carcinoma (OSCC) cell lines in flow cytometry and Western blot analyses. It exhibited a plasma membrane-like stain pattern in OSCC tissues upon immunohistochemical analysis. The K_D for EpMab-16 in SAS and HSC-2 OSCC cells were assessed via flow cytometry at 1.1×10⁻⁸ and 1.9×10⁻⁸ M, respectively, suggesting moderate binding affinity of EpMab-16 for EpCAM. We then assessed whether the EpMab-16 induced antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) against OSCC cell lines, and antitumor capacity in a murine xenograft model. In vitro experiments revealed strong ADCC and CDC inducement against OSCC cells treated with EpMab-16. In vivo experiments on OSCC xenografts revealed that EpMab-16 treatment significantly reduced tumor growth compared with the control mouse IgG. These data indicated that EpMab-16 could be a promising treatment option for EpCAM-expressing OSCCs.

Age and risk of recurrence in oral tongue squamous cell carcinoma: Systematic review

The incidence of oral tongue squamous cell carcinoma has been increasing in young patients (≤45 years) without a clear etiologic driver. It is unknown if younger patients have an increased risk of recurrence compared to older patients. A literature search was conducted through January 2020 using PubMed/MEDLINE, Embase, Cochrane, Scopus, Science Direct, and clinicaltrials.gov. This review was registered with PROSPERO (ID: CRD42020167498) and the PRISMA statement was followed. Studies were eligible for inclusion if they assessed risk of recurrence by age using a time-to-event analysis, used an age cutoff of ≤45 years or less for the younger cohort, and limited the analysis to the oral tongue subsite. Data were extracted independently by two reviewers using a form with a prespecified list of variables. There were 13 articles that met criteria for the qualitative synthesis (n = 1763 patients). The reported 5-year rates of disease-free survival ranged from 30% to 72% for the younger cohorts and 42% to 81% for the older cohorts. Three studies reported a statistically significant increased risk of recurrence in younger patients, three studies reported a nonsignificant increased risk in younger patients, and seven studies reported a similar risk in younger patients based on the time-to-event analyses. There may be an increased risk of recurrence for younger patients with oral tongue cancer. A definitive conclusion is precluded by limitations among individual studies, and additional research is warranted to examine this question.

Oncogenes overexpressed in metastatic oral cancers from patients with pain: potential pain mediators released in exosomes

Oral cancer patients experience pain at the site of the primary cancer. Patients with metastatic oral cancers report greater pain. Lack of pain identifies patients at low risk of metastasis with sensitivity = 0.94 and negative predictive value = 0.89. In the same cohort, sensitivity and negative predictive value of depth of invasion, currently the best predictor, were 0.95 and 0.92, respectively. Cancer pain is attributed to cancer-derived mediators that sensitize neurons and is associated with increased neuronal density. We hypothesized that pain mediators would be overexpressed in metastatic cancers from patients reporting high pain. We identified 40 genes overexpressed in metastatic cancers from patients reporting high pain (n = 5) compared to N0 cancers (n = 10) and normal tissue (n = 5). The genes are enriched for functions in extracellular matrix organization and angiogenesis. They have oncogenic and neuronal functions and are reported in exosomes. Hierarchical clustering according to expression of neurotrophic and axon guidance genes also separated cancers according to pain and nodal status. Depletion of exosomes from cancer cell line supernatant reduced nociceptive behavior in a paw withdrawal assay, supporting a role for exosomes in cancer pain. The identified genes and exosomes are potential therapeutic targets for stopping cancer and attenuating pain.

A defucosylated anti-PD-L1 monoclonal antibody 13-mG2a-f exerts antitumor effects in mouse xenograft models of oral squamous cell carcinoma

Programmed cell death ligand-1 (PD-L1) is a type I transmembrane glycoprotein expressed on antigen-presenting cells and several tumor cells, including melanoma and lung cancer cells. A strong correlation has been reported between PD-L1 expression in tumor cells and negative prognosis in cancer patients. Previously, we established an anti-PD-L1 monoclonal antibody (mAb), L₁Mab-13 (IgG₁, kappa), by immunizing mice with PD-L1-overexpressing CHO-K1 cells. L₁Mab-13 specifically reacts with endogenous PD-L1 in lung cancer cell lines in flow cytometry and Western blot applications, and stains a plasma membrane-like pattern in lung cancer tissues via immunohistochemical analysis. In this study, we investigated whether L₁Mab-13 reacts with oral cancer cell lines and exerts antitumor activities. Because L₁Mab-13 lacks antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), we first converted the subclass of L₁Mab-13 from IgG₁ into IgG_2a (13-mG_2a), and further produced a defucosylated version (13-mG_2a-f) using FUT8-deficient ExpiCHO-S (BINDS-09) cells. Defucosylation of 13-mG_2a-f was confirmed using fucose-binding lectins, such as Aleuria aurantia and Pholiota squarrosa lectins. The dissociation constants (K _D) for 13-mG_2a-f in SAS and HSC-2 oral cancer cells were determined via flow cytometry to be 2.8 × 10^-9 M and 4.8 × 10^-9 M, respectively, indicating that 13-mG_2a-f possesses extremely high binding affinity. In vitro analysis demonstrated that 13-mG_2a-f showed moderate ADCC and CDC activities against SAS and HSC-2 oral cancer cells. In vivo analysis revealed that 13-mG_2a-f significantly reduced tumor development in SAS and HSC-2 xenografts in comparison to control mouse IgG, even after injection seven days post-tumor inoculation. Taken together, these data demonstrate that treatment with 13-mG_2a-f may represent a useful therapy for patients with PD-L1-expressing oral cancers.

A defucosylated anti‑CD44 monoclonal antibody 5‑mG2a‑f exerts antitumor effects in mouse xenograft models of oral squamous cell carcinoma

CD44 is widely expressed on the surface of most tissues and all hematopoietic cells, and regulates many genes associated with cell adhesion, migration, proliferation, differentiation, and survival. CD44 has also been studied as a therapeutic target in several cancers. Previously, an anti-CD44 monoclonal antibody (mAb), C₄₄Mab-5 (IgG₁, kappa) was established by immunizing mice with CD44-overexpressing Chinese hamster ovary (CHO)-K1 cells. C₄₄Mab-5 recognized all CD44 isoforms, and showed high sensitivity for flow cytometry and immunohistochemical analysis in oral cancers. However, as the IgG₁ subclass of C₄₄Mab-5 lacks antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC), the antitumor activity of C₄₄Mab-5 could not be determined. In the present study, we converted the mouse IgG₁ subclass antibody C₄₄Mab-5 into an IgG_2a subclass antibody, 5-mG_2a, and further produced a defucosylated version, 5-mG_2a-f, using FUT8-deficient ExpiCHO-S (BINDS-09) cells. Defucosylation of 5-mG_2a-f was confirmed using fucose-binding lectins, such as AAL and PhoSL. The dissociation constants (K_D) for 5-mG_2a-f against SAS and HSC-2 oral cancer cells were determined through flow cytometry to be 2.8×10⁻¹⁰ M and 2.6×10⁻⁹ M, respectively, indicating that 5-mG_2a-f possesses extremely high binding affinity. Furthermore, immunohistochemical staining using 5-mG_2a-f specifically stained the membranes of oral cancer cells. In vitro analysis demonstrated that 5-mG_2a-f showed moderate ADCC and CDC activities against SAS and HSC-2 oral cancer cells. In vivo analysis revealed that 5-mG_2a-f significantly reduced tumor development in SAS and HSC-2 ×enografts in comparison to control mouse IgG, even after injection seven days post-tumor inoculation. Collectively, these results suggest that treatment with 5-mG_2a-f may represent a useful therapy for patients with CD44-expressing oral cancers.

Cordycepin induces apoptosis in human tongue cancer cells in vitro and has antitumor effects in vivo

OBJECTIVE

This study was designed to explore the ability of cordycepin to disrupt human tongue cancer cell growth, and to assess the mechanistic basis for such anti-cancer activity.

METHODS

CAL-27 human tongue cancer cells were treated with cordycepin prior to analysis via CCK-8 assay in order to assess their proliferation. In addition, cell cycle progression and apoptotic death in these cells were measured via flow cytometry, while the expression of apoptosis-associated genes and proteins (caspase-3, caspase-9, caspase-12, Bcl-2, and Bax) were measured via real-time PCR and western blotting. We further measured the intracellular production of reactive oxygen species (ROS) and used a murine xenograft model system to explore the in vivo anti-tumor activity of cordycepin.

RESULTS

Cordycepin was able to significantly suppress the proliferation of CAL-27 cells in a dose-dependent fashion (IC₅₀ = 40 μg/mL at 24 h). Cordycepin further induced Bax, caspase-3, caspase-9, and caspase-12 upregulation at the mRNA and protein levels while simultaneously downregulating anti-apoptotic Bcl-2 expression. CAL-27 cells treated using cordycepin also exhibited elevated levels of intracellular ROS. Importantly, cordycepin was able to effectively suppress tongue cancer tumor growth in a murine xenograft model system and similar mRNA and protein levels were observed in vivo.

CONCLUSIONS

Cordycepin can inhibit human tongue cancer cell growth and can drive their apoptotic death via the mitochondrial pathway. In addition, cordycepin can suppress tongue cancer growth in vivo in treated mice.

Clinicopathological and prognostic significance of PD-L1 in oral cancer: A preliminary retrospective immunohistochemistry study

OBJECTIVE

To evaluate the relation between PD-L1 expression in oral cavity squamous cell carcinomas and clinicopathological features as well as survival outcomes.

METHODS

A retrospective immunohistochemical study was carried out on 55 archived tumours from 55 patients. Tumours were stained for PD-L1 and scored by the proportion of tumour cells with positive membranous staining. PD-L1 scores were compared to the patient's clinicopathological characteristics for any significant associations. Kaplan-Meier curves were constructed for PD-L1 positive and negative tumours to investigate any advantage to survival.

RESULTS

Positive PD-L1 staining was found in 58% of tumours and was significantly more likely in non-smokers, non-drinkers and in tongue squamous cell carcinomas. Increased PD-L1 was also associated with increased lymphocyte infiltration as well as PD-L1 staining in lymphocytes and the epithelium adjacent to tumour invasion. No survival benefit was seen from PD-L1 expression in tumour cells.

CONCLUSIONS

PD-L1 expression is more common in non-smokers and non-drinkers, and its presence in the adjacent non-tumour epithelium suggests it may be involved in early oncogenesis.

The Role of Age and Merkel Cell Polyomavirus in Oral Cavity Cancers

The incidence of oral tongue cancer, the majority subsite of oral cavity cancer, is rising among young people with less exposure to tobacco and alcohol. Viral causes have been proposed, including Merkel cell polyomavirus (MCPyV). We evaluated patient and tumor characteristics among 126 incident oral cavity cancers (OCCs). Consistent with generational norms, younger patients had less exposure to tobacco and a greater number of oral sexual partners than older OCCs. In addition, younger patients were more likely to present at an earlier stage and with cancer arising from the oral tongue (each P < .05). A subset of 44 cases was centrally tested for MCPyV large T antigen expression by immunohistochemistry. In the presence of controls, none of the tumors expressed MCPyV. These findings exclude consideration of MCPyV as an etiologic factor in OCC and may generate hypotheses for future examinations of the factors underlying the rise in oral tongue cancers.

[Effects of RAB1A on the proliferation, invasion, and metastasis of tongue squamous cell carcinoma cells]

OBJECTIVE

This study aimed to investigate the molecular mechanism of RAB1A in the proliferation, invasion, and metastasis of human tongue squamous cell carcinoma.

METHODS

Western blot was used to detect the expression of RAB1A protein in human normal tongue epithelial cells (Hacat) and tongue squamous cell carcinoma Tca8113. The changes in RAB1A after plasmid transfection were also studied. The Tca8113 cells were named SiRAB1A/Tca8113 after RAB1A plasmid transfection. The expression of the epithelial-mesenchymal transition (EMT)-related markers of SiRAB1A/Tca8113 cells was also detected. CCK-8 assay was used to detect the proliferation of SiRAB1A/Tca8113 cells. Transwell and wound healing assays were used to detect the invasive and metastatic abilities of SiRAB1A/Tca8113 cells, respectively.

RESULTS

Western blot results showed that the expression of RAB1A in tongue squamous cell carcinoma cells was significantly higher than that in Hacat. RAB1A decreased significantly after SiRAB1A plasmid transfection. CCK-8 proliferation assay showed that the proliferation of SiRAB1A/Tca8113 cells also decreased significantly. Transwell and wound healing assays demonstrated that the invasive and metastatic abilities of SiRAB1A/Tca8113 cells decreased significantly, respectively. In addition, Western blot results demonstrated that RAB1A deletion significantly increased the expression of E-cadherin and inhibited the expression of Vimentin.

CONCLUSIONS

RAB1A could promote the proliferation, invasion, and metastasis of tongue squamous cell carcinoma cells.

An Integrated Approach for Preventing Oral Cavity and Oropharyngeal Cancers: Two Etiologies with Distinct and Shared Mechanisms of Carcinogenesis

Head and neck squamous cell carcinoma (HNSCC) was the 7th most common malignancy worldwide in 2018 and despite therapeutic advances, the overall survival rate for oral squamous cell carcinoma (OSCC; ∼50%) has remained unchanged for decades. The most common types are OSCC and oropharyngeal squamous cell carcinoma (OPSCC, survival rate ∼85%). Tobacco smoking is a major risk factor of HNSCC. In the developed world, the incidence of OSCC is declining as a result of tobacco cessation programs. However, OPSCC, which is also linked to human papillomavirus (HPV) infection, is on the rise and now ranks as the most common HPV-related cancer. The current state of knowledge indicates that HPV-associated disease differs substantially from other types of HNSCC and distinct biological differences between HPV-positive and HPV-negative HNSCC have been identified. Although risk factors have been extensively discussed in the literature, there are multiple clinically relevant questions that remain unanswered and even unexplored. Moreover, existing approaches (e.g., tobacco cessation, vaccination, and chemoprevention) to manage and control this disease remain a challenge. Thus, in this review, we discuss potential future basic research that can assist in a better understanding of disease pathogenesis which may lead to novel and more effective preventive strategies for OSCC and OPSCC.

H2Mab-19, an anti-human epidermal growth factor receptor 2 monoclonal antibody exerts antitumor activity in mouse oral cancer xenografts

Human epidermal growth factor receptor 2 (HER2) is reported to be overexpressed in breast cancers and is associated with poor clinical outcome. Trastuzumab is a humanized anti-HER2 antibody that offers significant survival benefits to patients with HER2-overexpressing breast cancer. In this study, a novel anti-HER2 monoclonal antibody (mAb), H₂Mab-19 (IgG_2b, kappa) was developed. Antibody-dependent cellular cytotoxicity (ADCC), complement-dependent cytotoxicity (CDC), and antitumor activity of H₂Mab-19 were investigated using both breast cancer and oral cancer cell lines. H₂Mab-19 demonstrated cytotoxicity in BT-474 (a human breast cancer cell line) and HSC-2 or SAS (human oral cancer cell lines). H₂Mab-19 also possessed both ADCC and CDC activity against BT-474, HSC-2, and SAS cell lines. In comparison to control mouse IgG, H₂Mab-19 significantly reduced tumor development in BT-474, HSC-2, and SAS xenografts. Collectively, these results suggest that treatment with H₂Mab-19 may be a useful therapy for patients with HER2-expressing breast and oral cancers.

Increasing incidence and improving survival of oral tongue squamous cell carcinoma

We evaluated changes in incidence, relative survival (RS), and conditional survival (CS) of head and neck squamous cell carcinoma (HNSCC), focusing on oral tongue squamous cell carcinoma (OTSCC). Data of 74 680 HNSCC patients from 1976 to 2015 were obtained from the Surveillance, Epidemiology, and End Results database. Five anatomical sites and their subsites were analyzed. Annual percent change (APC) of incidence was calculated. RS and CS were compared across the four decades. Adjusted hazard ratios (aHRs) of RS were evaluated using multivariate regression. OTSCC incidence decreased from 1976 (APC = −0.76, P < 0.05) but has increased since 1999 (APC = 2.36, P < 0.05). During 2006–2015, the 5-year CS exceeded 90% only for OTSCC and oropharyngeal squamous cell carcinoma (OPSCC). RS improved in OTSCC (aHR = 0.697, 95% confidence interval [CI] 0.642–0.757, P < 0.001) and OPSCC (aHR = 0.669, 95% CI 0.633–0.706, P < 0.001) during the last two decades. For both OTSCC and OPSCC, improved survival was observed regardless of treatment. Incidence and survival remained unchanged for nasopharyngeal, hypopharyngeal, and laryngeal cancers during this period. In conclusion, OTSCC incidence has been increasing since the 2000s, with improving prognosis irrespective of treatment. Given its similarity to OPSCC, OTSCC may represent an emerging HNSCC, warranting further research and clinical recognition.

Sex differences in cancer mechanisms

We now know that cancer is many different diseases, with great variation even within a single histological subtype. With the current emphasis on developing personalized approaches to cancer treatment, it is astonishing that we have not yet systematically incorporated the biology of sex differences into our paradigms for laboratory and clinical cancer research. While some sex differences in cancer arise through the actions of circulating sex hormones, other sex differences are independent of estrogen, testosterone, or progesterone levels. Instead, these differences are the result of sexual differentiation, a process that involves genetic and epigenetic mechanisms, in addition to acute sex hormone actions. Sexual differentiation begins with fertilization and continues beyond menopause. It affects virtually every body system, resulting in marked sex differences in such areas as growth, lifespan, metabolism, and immunity, all of which can impact on cancer progression, treatment response, and survival. These organismal level differences have correlates at the cellular level, and thus, males and females can fundamentally differ in their protections and vulnerabilities to cancer, from cellular transformation through all stages of progression, spread, and response to treatment. Our goal in this review is to cover some of the robust sex differences that exist in core cancer pathways and to make the case for inclusion of sex as a biological variable in all laboratory and clinical cancer research. We finish with a discussion of lab- and clinic-based experimental design that should be used when testing whether sex matters and the appropriate statistical models to apply in data analysis for rigorous evaluations of potential sex effects. It is our goal to facilitate the evaluation of sex differences in cancer in order to improve outcomes for all patients.

Significance of 125I radioactive seed implantation on growth differentiation factor and programmed death receptor-1 during treatment of oral cancer

BACKGROUND

Oral cancer (OC) is the most common malignant tumor in the oral cavity, and is mainly seen in middle-aged and elderly men. At present, OC is mainly treated clinically by surgery or combined with radiotherapy and chemotherapy; but recently, more and more studies have shown that the stress trauma caused by surgery and the side effects of radiotherapy and chemotherapy seriously affect the prognosis of patients.

AIM

To determine the significance of ¹²⁵I radioactive seed implantation on growth differentiation factor 11 (GDF11) and programmed death receptor-1 (PD-1) during treatment of OC.

METHODS

A total of 184 OC patients admitted to The Second Affiliated Hospital of Jiamusi University from May 2015 to May 2017 were selected as the research subjects for prospective analysis. Of these patients, 89 who received ¹²⁵I radioactive seed implantation therapy were regarded as the research group (RG) and 95 patients who received surgical treatment were regarded as the control group (CG). The clinical efficacy, incidence of adverse reactions and changes in GDF11 and PD-1 before treatment (T0), 2 wk after treatment (T1), 4 wk after treatment (T2) and 6 wk after treatment (T3) were compared between the two groups.

RESULTS

The efficacy and recurrence rate in the RG were better than those in the CG (P < 0.05), while the incidence of adverse reactions and survival rate were not different. There was no difference in GDF11 and PD-1 between the two groups at T0 and T1, but these factors were lower in the RG than in the CG at T2 and T3 (P < 0.05). Using receiver operating characteristic (ROC) curve analysis, GDF11 and PD-1 had good predictive value for efficacy and recurrence (P < 0.001).

CONCLUSION

¹²⁵I radioactive seed implantation has clinical efficacy and can reduce the recurrence rate in patients with OC. This therapy has marked potential in clinical application. The detection of GDF11 and PD-1 in patients during treatment showed good predictive value for treatment efficacy and recurrence in OC patients, and may be potential targets for future OC treatment.

Black Raspberry Inhibits Oral Tumors in Mice Treated with the Tobacco Smoke Constituent Dibenzo(def,p)chrysene Via Genetic and Epigenetic Alterations

We previously reported that the environmental pollutant and tobacco smoke constituent dibenzo[def,p]chrysene (DBP) induced DNA damage, altered DNA methylation and induced oral squamous cell carcinoma (OSCC) in mice. In the present study, we showed that 5% dietary black raspberry (BRB) significantly reduced (P < 0.05) the levels of DBP-DNA adducts in the mouse oral cavity with comparable effect to those of its constitutes. Thus, only BRB was selected to examine if aberrant DNA methylation induced by DBP can be altered by BRB. Using comparative genome-wide DNA methylation analysis, we identified 479 hypermethylated and 481 hypomethylated sites (q < 0.01, methylation difference >25%) between the oral tissues of mice treated with DBP and fed control diet or diet containing BRB. Among the 30 differential methylated sites (DMS) induced by DBP, we found DMS mapped to Fgf3, Qrich2, Rmdn2, and Cbarp were hypermethylated by BRB whereas hypomethylated by DBP at either the exact position or proximal sites; DMS mapped to Vamp3, Ppp1rB1, Pkm, and Zfp316 were hypomethylated by BRB but hypermethylated by DBP at proximal sites. In addition to Fgf3, 2 DMS mapped to Fgf4 and Fgf13 were hypermethylated by BRB; these fibroblast growth factors are involved in regulation of the epithelial-mesenchymal transition (EMT) pathway as identified by IPA. Moreover, BRB significantly reduced (P < 0.05) the tumor incidence from 70% to 46.7%. Taken together, the inhibitory effects of BRB on DNA damage combined with its effects on epigenetic alterations may account for BRB inhibition of oral tumorigenesis induced by DBP. SIGNIFICANCE: We provided mechanistic insights that can account for the inhibition of oral tumors by BRB, which could serve as the framework for future chemopreventive trials for addicted smokers as well as non- or former smokers who are exposed to environmental carcinogens.

Characteristics and prognosis of primary treatment-naïve oral cavity squamous cell carcinoma in Norway, a descriptive retrospective study

Objectives

Incidence of oral cavity squamous cell carcinomas is rising worldwide, and population characterization is important to follow for future trends. The aim of this retrospective study was to present a large cohort of primary oral cavity squamous cell carcinoma from all four health regions of Norway, with descriptive clinicopathological characteristics and five-year survival outcomes.

Materials and methods

Patients diagnosed with primary treatment-naïve oral cavity squamous cell carcinomas at all four university hospitals in Norway between 2005–2009 were retrospectively included in this study. Clinicopathological data from the electronic health records were compared to survival data.

Results

A total of 535 patients with primary treatment-naïve oral cavity squamous cell carcinomas were identified. The median survival follow-up time was 48 months (range 0–125 months) after treatment. The median five-year overall survival was found to be 47%. Median five-year disease-specific survival was 52%, ranging from 80% for stage I to 33% for stage IV patients. For patients given treatment with curative intent, the overall survival was found to be 56% and disease-specific survival 62%. Median age at diagnosis was 67 years (range 24–101 years), 64 years for men and 72 years for women. The male: female ratio was 1.2. No gender difference was found in neither tumor status (p = 0.180) nor node status (p = 0.266), but both factors influenced significantly on survival (p<0.001 for both).

Conclusions

We present a large cohort of primary treatment-naïve oral cavity squamous cell carcinomas in Norway. Five-year disease-specific survival was 52%, and patients eligible for curative treatment had a five-year disease-specific survival up to 62%.

Comparison of supervised machine learning classification techniques in prediction of locoregional recurrences in early oral tongue cancer

BACKGROUND

The proper estimate of the risk of recurrences in early-stage oral tongue squamous cell carcinoma (OTSCC) is mandatory for individual treatment-decision making. However, this remains a challenge even for experienced multidisciplinary centers.

OBJECTIVES

We compared the performance of four machine learning (ML) algorithms for predicting the risk of locoregional recurrences in patients with OTSCC. These algorithms were Support Vector Machine (SVM), Naive Bayes (NB), Boosted Decision Tree (BDT), and Decision Forest (DF).

MATERIALS AND METHODS

The study cohort comprised 311 cases from the five University Hospitals in Finland and A.C. Camargo Cancer Center, São Paulo, Brazil. For comparison of the algorithms, we used the harmonic mean of precision and recall called F1 score, specificity, and accuracy values. These algorithms and their corresponding permutation feature importance (PFI) with the input parameters were externally tested on 59 new cases. Furthermore, we compared the performance of the algorithm that showed the highest prediction accuracy with the prognostic significance of depth of invasion (DOI).

RESULTS

The results showed that the average specificity of all the algorithms was 71% . The SVM showed an accuracy of 68% and F1 score of 0.63, NB an accuracy of 70% and F1 score of 0.64, BDT an accuracy of 81% and F1 score of 0.78, and DF an accuracy of 78% and F1 score of 0.70. Additionally, these algorithms outperformed the DOI-based approach, which gave an accuracy of 63%. With PFI-analysis, there was no significant difference in the overall accuracies of three of the algorithms; PFI-BDT accuracy increased to 83.1%, PFI-DF increased to 80%, PFI-SVM decreased to 64.4%, while PFI-NB accuracy increased significantly to 81.4%.

CONCLUSIONS

Our findings show that the best classification accuracy was achieved with the boosted decision tree algorithm. Additionally, these algorithms outperformed the DOI-based approach. Furthermore, with few parameters identified in the PFI analysis, ML technique still showed the ability to predict locoregional recurrence. The application of boosted decision tree machine learning algorithm can stratify OTSCC patients and thus aid in their individual treatment planning.

Feasibility and acceptance of oral human papillomavirus detection in the dental office: Results from The National Dental Practice-Based Research Network

BACKGROUND

Oral human papillomavirus (HPV) infection is the principal underlying cause of a dramatic increase in oropharyngeal cancer. Dentistry can play an important role in developing clinical algorithms for secondary prevention.

METHODS

The authors conducted this cross-sectional pilot study with practices of The National Dental Practice-Based Research Network. The authors evaluated the feasibility and acceptability of screening and testing procedures as judged by practitioners and patients. The authors used tablet devices for patient screening, obtaining consent, and administering a confidential oral HPV risk factor survey.

RESULTS

Most patients (85%) were comfortable being asked about their cigarette use and their sexual behavior (69%) and were interested in participating again (79%). More than 90% of practitioners were comfortable with study procedures except the extra time required for patient participation (75% comfortable). There were no problems with oral rinse collection as reported by patients or practitioners.

CONCLUSIONS

It is feasible in community dental offices to collect oral rinses for HPV detection and to ask patients explicit questions about sexual history when using a tablet device for confidentiality.

PRACTICAL IMPLICATIONS

Discussing high-risk types of HPV and appropriately assessing that risk are a challenge for oral health care professionals. These results are positive from a research perspective but do not address the advisability of routine HPV screening in dentistry.

Evaluating the Utility and Prevalence of HPV Biomarkers in Oral Rinses and Serology for HPV-related Oropharyngeal Cancer

Performance of commercially available human papillomavirus (HPV) assays (approved for cervical HPV detection) is unknown for detecting HPV-related oropharyngeal cancer (HPV-OPC). Assays for detection of HPV DNA [ELISA (DEIA) and Cobas], and RNA (Aptima) in oral rinse samples, and serum HPV oncogene antibodies were evaluated. Sensitivity and specificity of each test was explored among HPV-OPC cases and controls. Biomarker prevalence was evaluated among 294 "at-risk" people (screening) and 133 "high-risk" people [known to previously have oral oncogenic HPV (oncHPV) DNA and/or HPV16 E6/E7 antibodies detected]. HPV16 E6 antibodies had the best overall test performance with sensitivity of 88%, compared with oral HPV16 DNA sensitivity of 51% by DEIA and 43% by Cobas (each P < 0.001). Specificity was comparable in each of these tests (≥98%). When positivity for any oncHPV type was compared with HPV16 for the same test, sensitivity was comparable (60% vs. 51%, 40% vs. 43%, and 92% vs. 88% for DEIA, Cobas, and E6 antibodies, respectively), but specificity was reduced (93%-97%). Aptima had poor sensitivity (23%). Sensitivity decreased when cotesting HPV16 oral rinse DNA and E6 antibodies (37%-48%), or multiple E antibodies (69%-72%). HPV16 DNA were detected in ∼2% of the at-risk by either DEIA or Cobas and up to 15% of the high-risk population. HPV16 E6 seroprevalence was 2.3% and 2.4% in the at-risk and high-risk populations, respectively. Oral rinse HPV testing had moderate-to-poor sensitivity for HPV-OPC, suggesting many true positives would be missed in a potential screening scenario. HPV16 E6 serum antibody was the most promising biomarker evaluated.

Comparative Analysis of Radial Forearm Free Flap and Anterolateral Thigh Flap in Tongue Reconstruction after Radical Resection of Tongue Cancer

BACKGROUND

Surgery is still the preferred treatment for tongue cancer. Reconstruction should be performed immediately after extensive resection of the tumor. The purpose of this study was to investigate the clinical effect, advantages, and disadvantages of radial forearm free (RFF) flap and anterolateral thigh (ALT) flap in tongue reconstruction after radical resection of tongue cancer.

METHODS

Thirty-nine cases of tongue reconstruction with RFF flap or ALT flap from 2014 to 2018 were analyzed. The survival of the flap, the functional status after repair, and the influence on the donor area were examined, in addition to the advantages and disadvantages of the flap and the critical points of the technique.

RESULTS

Twenty-one cases with RFF flaps and 18 cases with ALT flaps showed complete flap survival. Among them, 1 case involved a venous vessel crisis after an ALT operation, and the flap survived after reoperation after thrombus removal and anastomosis. The recovery of tongue function was as follows: 41.0% patients exhibited normal speech, 43.6% patients exhibited near-normal speech, 12.8% patients exhibited vague speech, and 2.6% patients could not speak. There was no significant difference between the 2 groups (p = 0.134). The recovery of tongue flexibility was as follows: 41.0% of the patients had normal postoperative tongue flexibility, 43.6% of the patients had slightly limited tongue flexibility, 12.8% of the patients had severely limited tongue flexibility, and 2.6% of the patients were completely limited. The difference between the 2 groups was statistically significant (p = 0.045). The postoperative diet of patients was as follows: 51.3% of patients had a regular diet, 33.3% of patients had soft foods, 12.8% of patients received a fluid diet, and 2.6% of patients could not eat after the operation. There was no significant difference between the 2 groups (p = 0.209). The satisfaction of donor area was as follows: 46.2% of the patients were satisfied with the donor area, 51.3% of the patients were basically satisfied with the donor area satisfaction, and 2.6% of the patients were not satisfied with the donor area satisfaction. There was no significant difference between the 2 groups (p = 0.809).

CONCLUSION

The RFF flap is the most widely used technique in tongue reconstruction, especially in patients with tongue defects less than half of tongue tissue. However, for a large number of tissue defects caused by radical resection of advanced tongue cancer, the ALT flaps can provide a sufficient tissue volume, conceal scars after the operation, cause fewer complications in the donor area, and facilitate tongue function and aesthetic quality.

FLI-06 Intercepts Notch Signaling And Suppresses The Proliferation And Self-renewal Of Tongue Cancer Cells

Purpose

The Notch signaling pathway plays an oncogenic role in tongue squamous cell carcinoma. The aim of this study was to inhibit the proliferation and self-renewal of tongue cancer cells by applying Notch signaling pathway inhibitor FLI-06 (Selleck, USA) and to lay a foundation for the clinically targeted treatment of tongue cancer for the future.

Methods

The mRNA expression level of Notch1 and the overall survival rate of patients with tongue cancer were examined by analyzing the TCGA database. Tongue cancer cells were treated with FLI-06. Cell proliferation, apoptosis, and stem cell self-renewal ability were tested in appropriate ways. A xenograft mouse model was established to observe tumor growth.

Results

From the TCGA data, we demonstrated that patients with high expression of Notch1 had a poor prognosis. We observed that the Notch signaling pathway inhibitor FLI-06 can restrain the activation of the Notch signaling pathway, decrease cell proliferation and induce cell apoptosis in vitro. The xenograft experiment indicated that intraperitoneal injection of FLI-06 inhibited tumor growth and increased cell apoptosis. FLI-06 suppressed both the mRNA and protein expression of Notch receptor and Notch targeted genes. We also observed that FLI-06 suppressed the proliferation of tongue cancer stem cells.

Conclusion

FLI-06 can block the proliferation and self-renewal of tongue cancer cells. It is inferred that this compound, which inhibits the Notch signaling pathway, may serve as a potential targeted drug for the treatment of tongue cancer in the clinic.

The role of the T-N tract in advanced stage tongue cancer

BACKGROUND

We investigated the role of the soft tissue tract between the primary tumor and the neck lymph nodes, the "T-N tract," in patients with tongue squamous cell carcinoma at an advanced stage.

METHODS

We performed a compartmental tongue surgery in 233 patients. Cumulative incidence of relapses and overall survival curves were compared by T-N tract involvement. Multivariate Cox proportional hazards models were used to assess the independent role of T-N tract.

RESULTS

At 4 years of follow-up, patients with disease in the T-N tract experienced a significantly more distant recurrence (40%) than did patients without T-N tract involvement (22%; P = .02). Multivariate Cox models indicate a significant almost triple risk of distant metastases (hazard ratio [HR], 2.70; 95% CI, 1.01-7.19; P = .05) and double risk of death (HR, 2.09; 95%CI, 1.13-3.85; P = .02) in patients with "T-N tract involvement."

CONCLUSIONS

Our data show that the T-N tract plays an important role in prognosis and survival in patients with tongue cancer.

Increasing Incidence rates of Oropharyngeal Squamous Cell Carcinoma in Germany and Significance of Disease Burden Attributed to Human Papillomavirus

Increasing incidences of head and neck cancers and rising proportions of these associated with human papillomavirus (HPV), especially in the oropharynx, have been reported in international studies. So far, the trends and contribution of HPV to the number of newly diagnosed cases of oropharyngeal squamous cell carcinomas (OPSCC) in Germany are uncertain. We investigated HPV association and incidence rates in a cohort of consecutively included patients with OPSCC in Giessen 2000-2017, and compared our results with regional (Giessen and the federal state of Hesse), national (Germany), and international (United States) databases. Regional data show a significant increase in the overall incidence rates of oropharyngeal cancers and in the incidence of HPV-associated cancers of the subsites tonsils and oropharynx, whereas other oropharyngeal subsites show no significant change. Analysis of national databases shows a significant incidence increase in Germany and in the United States. The rise in incidence is predominantly attributable to male patients in the US population, whereas in Germany rising OPSCC incidence is more associated with females. There is a significant elevation of OPSCC incidence rates in Germany, which corresponds to the recognized incidence increase of HPV-related oropharyngeal cancers based on experimental data from consecutively included patients of our cohort. Our investigation shows different patterns of this increase in Germany and in the United States, which demonstrates spatial heterogeneity and the need for population-based investigations regarding the role of HPV in oropharyngeal cancer.

miRNA-10a promotes cancer cell proliferation in oral squamous cell carcinoma by upregulating GLUT1 and promoting glucose metabolism

MicroRNA-10a (miRNA-10a) promotes lung cancer; however, to the best of our knowledge, its involvement in other cancer types is unknown. The present study aimed to investigate the role of miRNA-10a in oral cancer. Expression levels of miRNA-10a and glucose transporter 1 (GLUT1) in tumor tissues and adjacent healthy tissues obtained from patients with oral squamous cell carcinoma (OSCC) were detected by reverse transcription-quantitative polymerase chain reaction. Correlation analysis between the expression levels of miRNA-10a and GLUT1 was performed using Pearson's correlation coefficient. It was identified that miRNA-10a and GLUT1 were upregulated in tumor tissues compared with adjacent healthy tissues of patients with OSCC. Expression levels of miRNA-10a and GLUT1 were positively correlated in tumor tissues but not in adjacent healthy tissues. In addition, miRNA-10a overexpression promoted glucose uptake and upregulated GLUT1 in OSCC cells. Furthermore, GLUT1 overexpression promoted glucose uptake; however, no significant increase in the expression level of miRNA-10a in OSCC cells was detected. Overexpression of miRNA-10a and GLUT1 promoted OSCC cell proliferation, while GLUT1-knockdown inhibited OSCC cell proliferation. GLUT1-knockdown also attenuated the enhancing effect of miRNA-10a overexpression on cancer cell proliferation. Therefore, miRNA-10a may promote cancer cell proliferation in OSCC by upregulating GLUT1 and promoting glucose metabolism.

Human papillomavirus DNA detection, p16INK4a, and oral cavity cancer in a U.S. population

OBJECTIVES

The role of HPV in oral cavity cancers was investigated using two markers of viral exposure.

MATERIALS AND METHODS

HPV DNA and p16^INK4a expression were evaluated in tumor tissue from a U.S. population-based sample of 122 invasive oral cavity cancer cases.

RESULTS

HPV DNA was detected in 38 of 122 (31%) oral cavity tumors. Seven genotypes were detected including HPV 16, which was found in 22% of tumors. p16^INK4a was expressed in 30% of tumors and was poorly correlated with HPV DNA detection (Kappa <0.1). Joint positivity for HPV 16 and/or 18 and p16^INK4a was observed in only 7% of cases. When comparing cases diagnosed in 1993-1999 and in 2000-2004, positivity for HPV DNA 16/18 increased from 19% to 39% (p = 0.02) and joint HPV 16/18 - p16^INK4a positivity increased from 0% to 12% (p = 0.01). For gingival tumors, HPV 16 and/or 18 positivity was 67% compared to 11-38% for other sites (p = 0.02); joint HPV 16/18 - p16^INK4a positivity was 33% compared to 0-8% for other sites (p = 0.01). The association of HPV with gingival tumors and more recent diagnosis period remained after adjustment for age and stage (p < 0.05). Neither HPV DNA nor p16^INK4a were associated with overall survival.

CONCLUSIONS

Based on both HPV DNA and p16^INK4a, HPV is etiologically linked to a limited subset of oral cavity cancers. However, the role of HPV in oral cavity cancer may vary widely by subsite and may have increased over time, similar to trends observed for oropharyngeal cancer.

Evolution in the management of oropharyngeal squamous cell carcinoma: systematic review of outcomes over the last 25 years

The treatment of oropharyngeal squamous cell carcinoma (SCC) has evolved over the last 25years, from open surgery to combined chemoradiotherapy, and now to the development of minimally invasive procedures, but evidence for the best treatment is lacking. We therefore did a systematic search of the MEDLINE database for studies published between 1992 and 2017 that reported oncological or functional outcomes, or both. Predefined inclusion and exclusion criteria were used for screening and selection, and 45 studies were chosen. Only one was a randomised controlled trial, all the rest were prospective or retrospective case series. The heterogeneities in their characteristics made meta-analysis impossible and only qualitative analysis was feasible. We found no conclusive evidence to suggest the advantage of one therapeutic approach over another, so we still cannot offer patients the "ideal" treatment. We have, however, raised the possibility of there being two different entities: human papillomavirus (HPV)-positive and HPV-negative disease.

Early onset oral tongue squamous cell carcinoma: Associated factors and patient outcomes

BACKGROUND

Incidence of oral tongue squamous cell carcinoma (OTC) is rising among those under age 50 years. The etiology is unknown.

METHODS

A total of 395 cases of OTC diagnosed and/or treated at Vanderbilt University Medical Center between 2000 and 2017 were identified. Of those, 113 (28.6%) were early onset (age < 50 years). Logistic regression was used to identify factors associated with early onset OTC. Cox proportional hazards models evaluated survival and recurrence.

RESULTS

Compared to typical onset patients, patients with early onset OTC were more likely to receive multimodality treatment (surgery and radiation; adjusted odds ratio [aOR], 2.7; 95% confidence interval [CI], 1.2-6.3) and report a history of snuff use (aOR, 5.4; 95% CI, 1.8-15.8) and were less likely to report a history of cigarette use (aOR, 0.5; 95% CI, 0.2-0.9). Early onset patients had better overall survival (adjusted hazard ratio, 0.6).

CONCLUSIONS

This is the largest study to evaluate factors associated with early onset OTC and the first to report an association with snuff.

Integrative analysis of gene expression profiles reveals distinct molecular characteristics in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) is the most common type of oral cancer. Despite advances in knowledge regarding the genome-scale gene expression pattern of oral cancer, the molecular portrait of OTSCC biology has remained unclear over the last few decades. Furthermore, studies concerning OTSCC gene-expression profiles are limited or inconsistent owing to tissue heterogeneity in single-cohort studies. Consequently, the present study integrated the profile datasets of three cohorts in order to screen for differentially expressed genes (DEGs), and subsequently identified the potential candidate genes and pathways in OTSCC through gene enrichment analysis and protein-protein interaction (PPI) network construction. Using the selected Gene Expression Omnibus datasets GSE13601, GSE31056 and GSE78060, 206 DEGs (125 upregulated and 81 downregulated) were identified in OTSCC, principally associated with extracellular matrix (ECM) organization and the phosphoinositide 3-kinase/protein kinase B signaling pathway. Furthermore, 146/206 DEGs were filtered into the PPI network and 20 hub genes were sorted. Further results indicated that the two most significant modules filtered from the PPI network were associated with ECM organization and human papillomavirus infection, which are important factors affecting OTSCC pathology. Overall, a set of OTSCC-associated DEGs has been identified, including certain key candidate genes that may be of vital importance for diagnosis, therapy and prevention of this disease.

Early onset oral tongue cancer in the United States: A literature review

The incidence of early onset oral tongue squamous cell carcinoma (OTC) has been increasing in the United States, and no clear etiology has been identified. Studies on this topic have generally been small and presented varied results. The goal of this review is to analyze and synthesize the literature regarding early onset OTC risk factors, outcomes, and molecular analyses within the US. To date, studies suggest that early onset OTC patients tend to have less heavy cigarette use than typical onset patients, but there may be an association between early onset OTC and smokeless tobacco (chewing tobacco and snuff) use. Early onset OTC is associated with similar or possibly improved survival compared to typical onset OTC. There has been no evidence to support a significant role for human papillomavirus in development of early onset OTC. Further research with larger cohorts of these patients is needed to better characterize this disease entity.

Copy number variation: A prognostic marker for young patients with squamous cell carcinoma of the oral tongue

Background

The incidence of squamous cell carcinoma of the oral tongue (SCCOT) is increasing in people under age 40. There is an urgent need to identify prognostic markers that help identify young SCCOT patients with poor prognosis in order to select these for individualized treatment.

Materials and methods

To identify genetic markers that can serve as prognostic markers for young SCCOT patients, we first investigated four young (≤40 years) and five elderly patients (≥50 years) using global RNA sequencing and whole‐exome sequencing. Next, we combined our data with data on SCCOT from the cancer genome atlas (TCGA), giving a total of 16 young and 104 elderly, to explore the correlations between genomic variations and clinical outcomes.

Results

In agreement with previous studies, we found that SCCOT from young and elderly patients was transcriptomically and also genomically similar with no significant differences regarding cancer driver genes, germline predisposition genes, or the burden of somatic single nucleotide variations (SNVs). However, a disparate copy number variation (CNV) was found in young patients with distinct clinical outcome. Combined with data from TCGA, we found that the overall survival was significantly better in young patients with low‐CNV (n = 5) compared to high‐CNV (n = 11) burden (P = 0.044).

Conclusions

Copy number variation burden is a useful single prognostic marker for SCCOT from young, but not elderly, patients. CNV burden thus holds promise to form an important contribution when selecting suitable treatment protocols for young patients with SCCOT.

Chemosensitizing effect of honokiol in oral carcinoma stem cells via regulation of IL-6/Stat3 signaling

Oral squamous cell carcinoma (OSCC) is one of the most common cancers worldwide with poor prognosis. Numerous studies have attempted to explore alternative regimens aimed at reducing cancer stem cells (CSCs) without compromising the efficacy of conventional chemoradiotherapy. The present study sought to assess the effect of a natural compound honokiol on the reduction of elevated cancer stemness, metastatic capacity, and chemoresistance of oral carcinoma stem cells (OCSCs). Our results demonstrated that honokiol attenuated the cell survival and self-renewal of OCSCs in a dose-dependent manner. Moreover, honokiol downregulated the expression of 2 selective markers of OCSCs, ALDH1, and CD44, as well as the migration and invasion abilities, indicating its potential to suppress cancer stemness. We showed that honokiol reduced the secretion of IL-6 and phosphorylation of STAT3, and the honokiol-inhibited self-renewal, invasion and colony formation were reversed by administration of IL-6. Most importantly, our data demonstrated that honokiol was able to potentiate the effect of Cisplatin, leading to a lower proportion of OCSCs and the decreased cancer stemness features. Taken together, this study demonstrated the benefits of utilizing honokiol as an adjunct therapy for OSCC treatment.

Neutrophil-Mediated Endogenous Analgesia Contributes to Sex Differences in Oral Cancer Pain

The incidence of oral cancer in the United States is increasing, especially in young people and women. Patients with oral cancer report severe functional pain. Using a patient cohort accrued through the New York University Oral Cancer Center and immune-competent mouse models, we identify a sex difference in the prevalence and severity of oral cancer pain. A neutrophil-mediated endogenous analgesic mechanism is present in male mice with oral cancer. Local naloxone treatment potentiates cancer mediator-induced orofacial nociceptive behavior in male mice only. Tongues from male mice with oral cancer have significantly more infiltrating neutrophils compared to female mice with oral cancer. Neutrophils isolated from the cancer-induced inflammatory microenvironment express beta-endorphin and met-enkephalin. Furthermore, neutrophil depletion results in nociceptive behavior in male mice. These data suggest a role for sex-specific, immune cell-mediated endogenous analgesia in the treatment of oral cancer pain.

A review of the most promising biomarkers for early diagnosis and prognosis prediction of tongue squamous cell carcinoma

BACKGROUND

There is a great interest in developing biomarkers to enhance early detection and clinical management of tongue squamous cell carcinoma (TSCC). However, the developmental path towards a clinically valid biomarker remains extremely challenging. Ideally, the initial key step in moving a newly discovered biomarker towards clinical implementation is independent replication. Therefore, the focus of this review is on biomarkers that consistently showed clinical relevance in two or more publications.

METHODS

We searched PubMed database for relevant papers across different TSCC sample sources, i.e., body fluids (saliva, serum/plasma) and tissues. No restriction regarding the date of publication was applied except for immunohistochemistry (IHC); only studies published between 2010 and June 2017 were included.

RESULTS

The search strategy identified 1429 abstracts, of which 96 papers, examining 150 biomarkers, were eventually included. Of these papers, 66% were exploratory studies evaluating single or a panel of biomarkers in one publication. Ultimately, based on studies that had undergone validation for their clinical relevance in at least two independent studies, we identified 10 promising candidates, consisting of different types of molecules (IL-6, IL-8, and Prolactin in liquid samples; HIF-1α, SOX2, E-cadherin, vimentin, MALAT1, TP53, and NOTCH1 in tissue biopsies) CONCLUSIONS: Although more exploratory research is needed with newer methods to identify biomarkers for TSCC, rigorous validation of biomarkers that have already shown unbiased assessment in at least two publications should be considered a high priority. Further research on these promising biomarkers or their combination in multi-institutional studies, could provide new possibilities to develop a specific panel for early diagnosis, prognosis, and individualized treatments.