Oral Tongue Squamous Cell Carcinoma Research Articles

Elective Neck Dissection Versus Observation in cT1-T2 Oral Tongue Squamous Cell Carcinoma: A Meta-Analysis of 11,973 Patients.

The surgical management of the clinical negative neck node in early oral tongue squamous cell carcinoma (OTSCC) has been the topic of debate since few decades. As the occult cervical lymph node metastasis is considered to be the prime prognostic factor in early OTSCC, this meta-analysis has been carried out to find the risk of regional nodal recurrence, disease specific survival and overall survival rates in outcome of Elective neck dissection (END) versus patients under observation. The articles were electronically retrieved from Ovid Medline, PubMed, Cochrane and Scholar for comparison of END versus Observation in early OTSCC. The search strategy identified 37 relevant review articles from April 1979 to April 2020 from different search engines. A total of 11,973 patients from 32 retrospective analysis, 4 prospective and 1 randomised control trial were included in this meta-analysis. Statistical analysis revealed Overall test (OR: 5.31 95% CI: - 2.132-14.698) with t-test 1.919 and p value 0.113 which is not statistically significant but the readings says that there is always better Disease specific survival with END patients rather than patients kept on observation. Overall test revealed (OR: 13.02 95% CI: 1.360-17.154) with t test 2.382 and p value 0.023 which is statistically significant and showed that End significantly reduced the risk of regional nodal recurrence. Overall test revealed (OR: 7.93 95% CI: - 15.461-4.238) with t test - 1.347 and p value 0.220 which is statistically insignificant and but showed that to some extent Overall survival improves in patient with END than the patients kept on observation. This meta-analysis find that there is statistically significant relationship when Elective neck dissection was performed which reduced the risk of regional nodal recurrence. This analysis didn't statistically find any significance in Disease specific survival and Overall survival with Elective neck dissection patients rather than patients kept on observation but however showed good prognosis when elective neck dissection was performed.

CLINICOPATHOLOGICAL AND PROGNOSTIC SIGNIFICANCE OF PAI-1 EXPRESSION IN ORAL TONGUE SQUAMOUS CELL CARCINOMA

Objective: The purpose of this study was to evaluate the expression of plasminogen activator inhibitor type-1 (PAI-1) and its association with clinicopathological parameters and survival rates of oral tongue squamous cell carcinoma (OTSCC). Study Design: Sixty cases of OTSCC were selected for morphologic and immunohistochemical study. Each case was histopathologically graded according to Almangush et al. (2015). Cytoplasmic and membrane immunoexpression of PAI-1 were semiquantitatively analyzed at the deep invasive front. Pearson χ2 and Fisher exact test were performed to investigate the relationship between immunohistochemical findings and clinicopathological characteristics. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Results: PAI-1 was highly expressed by neoplastic and stromal cells. No statistically significant associations were found between cytoplasmic immunopositivity for PAI-1 and clinical stage, nodal metastasis, local recurrence, disease outcome, or histopathological grade of malignancy (P> .05). Membrane immunopositivity for PAI-1 was significantly associated with tumor budding and histopathological risk-assessment score (P< .05). Cytoplasmic and membrane expression of PAI-1 were not associated with disease-specific or disease-free survival (P> .05). Conclusion: Our findings suggest that PAI-1 partly influences the biological behavior of OTSCC. However, the immunoexpression of this protein may not be useful to predict survival of the studied lesion. Objective: The purpose of this study was to evaluate the expression of plasminogen activator inhibitor type-1 (PAI-1) and its association with clinicopathological parameters and survival rates of oral tongue squamous cell carcinoma (OTSCC). Study Design: Sixty cases of OTSCC were selected for morphologic and immunohistochemical study. Each case was histopathologically graded according to Almangush et al. (2015). Cytoplasmic and membrane immunoexpression of PAI-1 were semiquantitatively analyzed at the deep invasive front. Pearson χ2 and Fisher exact test were performed to investigate the relationship between immunohistochemical findings and clinicopathological characteristics. Survival analyses were performed using the Kaplan-Meier method and log-rank test. Results: PAI-1 was highly expressed by neoplastic and stromal cells. No statistically significant associations were found between cytoplasmic immunopositivity for PAI-1 and clinical stage, nodal metastasis, local recurrence, disease outcome, or histopathological grade of malignancy (P> .05). Membrane immunopositivity for PAI-1 was significantly associated with tumor budding and histopathological risk-assessment score (P< .05). Cytoplasmic and membrane expression of PAI-1 were not associated with disease-specific or disease-free survival (P> .05). Conclusion: Our findings suggest that PAI-1 partly influences the biological behavior of OTSCC. However, the immunoexpression of this protein may not be useful to predict survival of the studied lesion.

STROMAL EXPRESSION OF TWIST AND PODOPLANIN IN ORAL TONGUE AND LOWER LIP SQUAMOUS CELL CARCINOMAS

Objective: To analyze podoplanin (PDPN) and Twist stromal immunoexpression profiles in a series of oral tongue squamous cell carcinoma (OTSCC) and lower lip squamous cell carcinoma (LLSCC) cases and evaluate their relationship with clinical-pathologic parameters. Study Design: PDPN and Twist immunoexpression were qualitatively evaluated by analyzing stromal fibroblast staining. The statistical associations and correlations with clinicopathologic characteristics were verified by the Mann-Whitney and Spearman tests. Results: In LLSCC, the male-to-female ratio was 3:1 with a mean age ± standard deviation (SD) of 66.8 ± 15.1 years, with the seventh decade being the most affected age group. In OTSCC, the male-to-female ratio was 3:1, with a mean age ± SD of 61.0 ± 12.7 years, with the sixth decade being the most affected age group. Regarding the clinical parameters in both lesions, there were no statistically significant results for PDPN; for Twist, stromal immunoexpression was statistically significant for cases in the earliest stages (I and II). In the Spearman test, a significant positive correlation was observed only in LLSCC cases (P

Prognostic Relevance of Macrophage Phenotypes in High-grade Oral Tongue Squamous Cell Carcinomas.

Tumor-associated macrophages (TAMs) are part of the tumor microenvironment, broadly divided into M1 and M2 phenotypes. M1 macrophages, commonly identified by staining the CD11c antigen, have an antitumour immunity role, while M2 macrophages, expressing the CD163 antigen, are involved in tumor progression. Little is known about M1 and M2 phenotypes in the context of the oral tongue squamous cell carcinomas (OTSCC), a subgroup of oral cancer with peculiar clinical behavior. This study evaluated the macrophage polarization in OTSCC specimens to examine their prognostic relevance. To this end, specimens from 71 OTSCC patients graded as G1 or G3 were investigated for CD11c and CD163 expression. Immunohistochemical staining of TAMs was evaluated in tumor nests, tumor inflammation area (TIA), and tumor stroma. To analyze the expression of CD11c and CD163, the percentage of positive cells was scored as 0 (negative), 1 (<10%), 2 (11% to 50%), 3 (51% to 80%), and 4 (>80%). The staining intensity was scored as 0 (negative), 1 (weak), 2 (moderate), and 3 (intense). Higher expression of both CD163+ and CD11c+ macrophages in inflammation area positively correlated with G3 grade, both in extension and intensity. Focusing on G3 tumors, survival curves showed better disease-free survival in patients with high CD11c expression in the TIA. Presence of CD163 expression in TIA was associated with worse disease-free survival. This study evaluated, for the first time, the distribution of M1 and M2 macrophages in relation to the pathologic grade in OTSCC, highlighting the prognostic relevance of analyzing the localization of TAMs.

Lymph node ratio as a prognostic marker of oral tongue squamous cell carcinoma: a cohort study.

Lymph node metastasis is a poor prognostic indicator and is well established in tongue squamous cell carcinoma. Based on the current staging system, accurate risk stratification is difficult. There is thus a need to evaluate an alternate method for predicting recurrence and survival. The objective of the study was to evaluate lymph node ratio as a prognostic marker as compared with N-staging for tongue squamous cell carcinoma. We conducted a retrospective cohort study with 56 patients with a lymph node ratio greater than 0.012 (exposed) and 74 patients with a lymph node ratio less than 0.012 (unexposed). Overall five-year survival and disease-free survival were assessed. The Cox proportional hazard model was used to analyse lymph node ratio as a predictor of outcome, together with other covariates. A total of 130 patients were included in the study. Patients with lymph node ratio greater than 0.012 had a poor overall five-year (mean survival time 52.1 months vs 38.1 months) and disease-free survival (mean survival time 53.6 months vs 39.2 months). The hazard of death among patients with a lymph node ratio greater than 0.012 was 3.24 times higher than the hazard of death among patients with a lymph node ratio less than 0.012 (95% confidence interval 1.82-5.77). Lymph node ratio is a superior prognostic marker compared with the currently used American Joint Committee on Cancer N-staging. Our findings also suggest that the margin status (involved) of the primary tumour resection adversely affects prognosis.

Abstract LB-310: Whole-exome sequencing reveals genetic underpinnings of salivary adenoid cystic carcinoma and tongue carcinoma in Chinese population

Abstract Background: Salivary adenoid cystic carcinoma (ACC) and oral tongue squamous cell carcinoma (OTSCC) are rare malignancies with low incidence and dismal prognosis. The molecular underpinnings of these remain poorly understood, particularly in Asian population. Methods: Through a whole-exome sequencing analysis of 13 OTSCC and 30 ACC patients, a systematic overview of the mutational features in single-nucleotide variations, copy number variations and chromosomal variations were illustrated. Results: In addition to the well-characterized alterations previously reported in Caucasian patients, such as TP53 mutations (11/13, 84.6%) in OTSCC and MYB-NFIB fusion in ACC (11/30, 36.7%), we also observed several novel genetic changes, including FOXP1-TEX261 fusion (1/13, 7.7%) and MYB-FMO5 fusion (1/30, 3.3%) in OTSCC and ACC respectively, which might play a role in facilitating tumor progression. The data exhibited promising translational value as numerous actionable genes were identified with mutations. 76.9% OTSCC and 20% salivary ACC harbored at least one alteration in actionable genes, mutations in CDKN2A (4/13, 30.8%), NTRK3 (3/13, 23.1%) in OTSCC and FGFR2 (2/30, 6.7%), BRAF (2/30, 6.7%) in salivary gland ACC, suggesting targeted immunotherapy might be an effective intervention. Instead of MYB-independent NFIB fusions previously reported in ACC, only NFIB-independent MYB fusions were found in our cohort, indicating that alterations in NFIB rather than MYB might be essential to ACC tumorigenesis. Conclusions: This study reveals the genetic underpinnings of two rare malignancies in Chinese population, illustrating consistent mutational features with published literature as well as demonstrating several distinct genetic alterations, warranting further investigations. Citation Format: Ning Li, Shuhang Wang, Yue Yu, Yuan Fang, Huiyao Huang, Dawei Wu, Hong Fang, Chao Sun, Anqi Yu, Qi Fan, Shi-Yuan Cheng. Whole-exome sequencing reveals genetic underpinnings of salivary adenoid cystic carcinoma and tongue carcinoma in Chinese population [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr LB-310.

Silenced Myeloblastosis Protein Suppresses Oral Tongue Squamous Cell Carcinoma via the microRNA-130a/Cylindromatosis Axis.

BackgroundOral tongue squamous cell carcinoma (OTSCC) represents oral epithelial cell damage. Myeloblastosis (MYB) is involved in OTSCC. This study tried to probe roles of MYB in OSCC with potential axis.MethodsExpression of MYB and miR-130a in OTSCC was detected. Western blot analysis was utilized to determine epithelial–mesenchymal transition-related protein levels. Dual-luciferase reporter gene assay certified the target relation between miR-130a and CYLD. Moreover, xenograft tumors in nude mice were applied to confirm the in vitro experiments.ResultsBoth MYB and miR-130a were highly expressed in OTSCC, which promoted cell growth. Meanwhile, silenced miR-130a discouraged cell development enhanced by overexpressed MYB. CYLD was poorly expressed in OTSCC and targeted by miR-130a. Additionally, MYB knockdown activated CYLD to suppress OTSCC by downregulating miR-130a.ConclusionOur experiment supported that silenced MYB suppressed OTSCC malignancy by inhibiting miR-130a and activating CYLD. This investigation may provide novel insights for OTSCC treatment.

Abstract B08: Therapeutic inhibition of YAP1 expression by next-generation antisense oligonucleotides leads to antitumor activity in head and neck squamous cell carcinoma with YAP1 activation

Abstract As the final effector of the Hippo pathway, YAP1 plays a driver role in promoting growth of a variety of tumor types. Unlike other oncogenic pathways, however, genetic alterations on the core components of the Hippo pathway leading to YAP1 activation are rare and have not been well characterized. Therefore, identifying alternate pathway alterations leading to YAP1-dependent tumors will be critical for clinical success of potential YAP1-targeted therapies. Recent reports have suggested that frequent mutations of tumor suppressor FAT1 might contribute to the progression of YAP1-dependent head and neck squamous cell carcinoma (HNSCC). In this study, we have investigated the underlying mechanisms for YAP1 activation in HNSCC, developed a therapeutic agent for the specific suppression of YAP expression, and identified a HNSCC subtype that is highly sensitive to YAP1 inhibition. We first screened and identified active human YAP1 antisense oligonucleotides (ASOs) with next-generation (constrained ethyl=cEt) chemistry and then evaluated them in a broad panel of human HNSCC lines in vitro. The majority of HNSCC lines were highly amenable to ASO free uptake (without any transfection agents), resulting in strong reductions of YAP1 and its downstream target genes such as CTGF, Cyr61, and Survivin in a dose-dependent manner. However, phenotypic consequences of YAP1 depletion varied significantly among the cell lines and were dependent upon the levels of functional FAT1 protein. Cell proliferation was strongly reduced by YAP1 ASOs in the cell lines harboring homozygous copy loss or nonsense mutations of FAT1, while minimal antiproliferative activity was observed in cells with wild-type FAT1 or YAP1 amplification. Importantly, the nuclear localization of YAP1 appeared to be a key determining factor for the sensitivity of HNSCC cells to YAP1 ASOs. Unexpectedly, in contrast to oral tongue SCC (OTSCC) lines that were generally sensitive to YAP1 ASOs, proliferation of FAT1 mutant HNSCC lines originated from larynx were minimally affected by YAP1 inhibition even with near-complete depletion of YAP1, suggesting variable dependency of tumor cells on YAP1 for their growth among different subtypes of HNSCC. Moreover, when systemically administered into mice bearing OTSCC with FAT1 mutations, YAP1 ASOs greatly reduced YAP1 expression in tumors and suppressed tumor growth in subcutaneous and more notably oral orthotopic xenograft models. These results suggest that OTSCC with YAP1 activation due to FAT1 loss is highly dependent on YAP1 for growth and that YAP1 ASOs have promise for the treatment of this cancer. Finally, through an extensive selection process the human YAP1 ASO clinical development compound, YAP1Rx, has been identified. Citation Format: Xiaolin Luo, Youngsoo Kim, Joanna Schmidt, Jian Li, Rachel Fleming, Shivani Malik, Stephanie Klein, A. Robert MacLeod. Therapeutic inhibition of YAP1 expression by next-generation antisense oligonucleotides leads to antitumor activity in head and neck squamous cell carcinoma with YAP1 activation [abstract]. In: Proceedings of the AACR Special Conference on the Hippo Pathway: Signaling, Cancer, and Beyond; 2019 May 8-11; San Diego, CA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(8_Suppl):Abstract nr B08.

Compartmental Surgery With Microvascular Free Flap Reconstruction in Patients With T1-T4 Squamous Cell Carcinoma of the Tongue: Analysis of Risk Factors, and Prognostic Value of the 8th Edition AJCC TNM Staging System.

Compartmental surgery and primary reconstruction with microvascular free flaps represent the gold-standard in the treatment of oral tongue squamous cell carcinoma (OTSCC). However, there are still unclear clinical features that negatively affect the outcomes. This retrospective study included 80 consecutive patients with OTSCC who underwent compartmental surgery and primary reconstruction by free flap. The oncologic outcomes, the reliability of the 8th edition American Joint Committee on Cancer (AJCC) staging system and the prognostic factors were evaluated. Fifty-nine males and 21 females (mean age 57.8 years, range 27–81 years) were treated between November 2010 and March 2018 (one patient had two metachronous primaries). Seventy-one patients (88.75%, 52 males, 19 females, mean age of 57.9 years, range of 27–81 years) had no clinical history of previous head and neck radiotherapy and were considered as naive. Histology showed radical surgery on 80/81 lesions (98.8%), with excision margins >0.5 cm, while in 1 case (1.2%), a close posterior margin was found. According to the 8th AJCC classification, 37 patients (45.7%) were upstaged shifting from the clinical to the pathological stage, and 39 (48.1%) showed an upstaging while shifting from the 7th to the 8th AJCC staging system (no tumors were downstaged). Nodal involvement was confirmed in 33 patients (40.7%). Perineural and lymphovascular invasion were present in 9 (11.1%) and 11 (13.6%) cases, respectively. Twenty-two patients (27.1%) underwent adjuvant therapy. The 5-years disease-specific, overall, overall relapse-free, locoregional relapse-free and distant metastasis-free survival rates were 73.2, 66.8, 62.6, 67.4, and 86%, respectively. Patients with a lymph node ratio >0.09 experienced significantly worse outcomes. Univariate analysis showed that patients with previous radiotherapy, stage IV disease, nodal involvement, and lymphovascular invasion had significantly worse outcomes. Multivariate analysis focused naive patients and showed that lymphovascular invasion, advanced stage of disease, and node involvement resulted reliable prognostic factors, and patients with the same tumor stage and histological risk factors who did not undergo adjuvant therapy experienced significantly worse outcomes. In our series, surgery played a major role in the treatment of local extension; adjuvant therapy resulted strictly indicated in patients with advanced-stage disease associated with risk factors.

MRI correlates to histopathological data in oral tongue squamous cell carcinoma diagnostics

Objectives The purpose of this study was to compare magnetic resonance imaging (MRI) maximum tumor diameter and depth of invasion with histopathology in oral tongue squamous cell carcinoma (OTSCC) patients in our Institute. Another objective was to compare recorded nodal status between MRI and histology. Material and methods MRI and pathological records of 45 patients diagnosed with T1–T3 OTSCC were reviewed retrospectively. Maximum tumor diameter and depth of invasion were measured and rechecked by oral radiologist and pathologist. Nodal status was recorded from both MRI and histopathology. Correlation analyses were performed using Pearson’s correlation. Results Both maximum tumor diameter and depth of invasion correlated significantly between MRI and histology (ρ = 0.874, p < .001; ρ = 0.898, p < .001). Significant correlation was found between MRI and pathological dimensions in the MRI-based T-staged subgroups of T2 and T3 but not in T1. MRI sensitivity for detecting pathologically positive nodes was 60%. MRI specificity for detecting pathologically negative nodes was 83%. Moderate correlation was found between MRI and histological nodal status (ρ = 0.44, p = .003). Conclusions MRI tumor dimensions correlate with histopathological data in OTSCC. Based on our Finnish patient material and results, MRI serves as an accurate tool in supporting OTSCC patient treatment in our Institute.

The incidence of squamous cell carcinoma of the oral tongue is rising in young non-smoking women: An international multi-institutional analysis.

Increasing evidence is accumulating for an alarming rising incidence of oral tongue SCC in a younger cohort, particularly in developed countries. The aim of this study is to analyse the change in incidence of OSCC in patients under the age of 45 in developed nations in the Asia-Pacific region. Population data was extracted from the Australian Cancer Incidence and Mortality 2017 database and National Registry of Diseases Office, Singapore to allow calculation of the incidence in the Australian and Singaporean populations. This was compared to multi-institutional data from four tertiary Australian institutions. The inclusion criteria were as follows: a) diagnosis of primary SCC of the mobile tongue; b) treatment with curative intent; c) complete histopathologic data; d) complete adjuvant treatment data; e) follow up data. Analysis of ACIM data demonstrated that there was a significant increase in the incidence of tongue SCC in those under the age of 45 in the Australian and Singaporean populations (p<0.001). When analysed for gender, the incidence of tongue SCC increased at a significantly higher rate in females than males (p<0.001). Similarly, in the multi-institutional analysis including 1814 patients, the number of females under the age of 45 with tongue SCC significantly increased over time (p<0.001), with the proportion of smokers in this cohort decreasing over time. The incidence of tongue SCC is rising in young females in developed nations in the Asia Pacific region, in keeping with observed epidemiological trends worldwide.

Iron chelation promotes 5-aminolaevulinic acid-based photodynamic therapy against oral tongue squamous cell carcinoma.

Oral tongue squamous cell carcinoma (OTSCC) is the most common malignancy of the oral cavity. Photodynamic therapy (PDT) has become a clinically promising approach for early stage OTSCC treatment. 5-Aminolaevulinic acid (5-ALA) is a precursor of protoporphyrin IX (PpIX) and has been applied for PDT of cancer. However, the accumulated PpIX in 5-ALA-treated cancer cells will be further transformed into heme through ferrous iron insertion under ferrochelatase catalysis. Theoretically, iron chelation can enhance the intracellular accumulation of PpIX and thus promote 5-ALA-based PDT. Here, an iron chelator deferasirox (DFX) was used to investigate synergistic suppression effects of 5-ALA-based PDT and iron chelation on OTSCC. In OTSCC SCC-25 cells, the enhancing effect of DFX on 5-ALA-mediated accumulation of PpIX was firstly assessed. After laser irradiation (635 nm, 200 mW/cm2 and 2 min), the synergistic cytotoxicity and apoptosis-inducing effect of 5-ALA and DFX were evaluated in SCC-25 cells, and the apoptosis mechanism was further investigated by monitoring the change of mitochondrial membrane potential and observing the subcellular localization of cytochrome c (Cyt c). In SCC-25 tumor-bearing mice, the synergistic suppression effects of 5-ALA-based PDT and DFX on tumor growth and tumor angiogenesis were investigated after laser irradiation on the tumor (635 nm, 150 mW/cm2 and 10 min). In SCC-25 cells, DFX showed strong iron chelation effect and enhanced 5-ALA-mediated intracellular accumulation of PpIX by 2-3 folds. After laser irradiation (635 nm, 200 mW/cm2 and 2 min), 5-ALA combined with DFX exhibited significant synergistic effects on cytotoxicity and cell apoptosis. In the treated cells, the damage of mitochondrial membrane and the release of Cyt c from mitochondria to cytoplasm were observed distinctly, indicating the activation of mitochondria-related signal pathway. In SCC-25 tumor-bearing mice, tumor growth and tumor angiogenesis were both notably suppressed by combination treatment of 5-ALA with laser irradiation and DFX. Meanwhile, no obvious toxic injuries were visible in histological examination of major organs in the treated mice. 5-ALA-based PDT combined with iron chelation synergistically inhibited the growth of OTSCC. Hence it can be seen that this combination therapy may represent a promising strategy for clinical treatment of OTSCC and other cancers.

A combined histo-score based on tumor differentiation and lymphocytic infiltrate is a robust prognostic marker for mobile tongue cancer

We wanted to evaluate the prognostic value of common histopathological variables in a large cohort of patients with cancer in the mobile tongue as such information can be important for treatment stratification of the individual patient, especially for patients with low-stage disease. In addition, we wanted to investigate whether an alternative scoring model with fewer options would compromise the prognostic value. One hundred fifty patients with oral tongue squamous cell carcinomas that were treated in curative intent and with available HE-stained tumor sections were included. We reclassified all tumors and performed univariate and multivariate survival analyses of histopathological and clinical variables. For the complete cohort, lymph node status, grade of differentiation, perineural infiltration, and lymphocytic infiltration were independent prognosticators. In the low-stage disease group, independent prognostic factors were tumor size, grade of differentiation, and lymphocytic infiltrate. For patients with low-stage disease, a histo-score combining the scores for tumor differentiation and lymphocytic infiltrate identified a group of patients with particularly low survival, as patients with moderately or poorly differentiated tumors and little lymphocytic infiltrate had a less favorable 5-year survival outcome than patients in the high-stage disease group. This study shows that a histo-score combining tumor differentiation and lymphocytic infiltration should be given special consideration in treatment planning. Our results also illustrate that many variables can be scored with fewer options than previously suggested to increase their reproducibility, and still maintain their prognostic value.

TIPE2 suppresses progression and tumorigenesis of the oral tongue squamous cell carcinoma by regulating FoxP3+ regulatory T cells.

To discover the effect of tumor necrosis factor-alpha-induced protein 8-like 2 (TIPE2) on the oral tongue squamous cell carcinoma (OTSCC) via affecting FoxP3+ regulatory T (Treg) cells. Immunohistochemistry was conducted to examine TIPE2 and FoxP3 expressions in OTSCC tumor tissues and corresponding oral mucosa. Tca8113 cells were transfected with TIPE2/control lentiviral activation particles followed by the detection with qRT-PCR, Western blotting, MTT assay, Wound healing, Transwell assay and Annexin V-FITC/PI staining. In vivo experiment was carried out on the nude mice xenografts of OTSCC with TIPE2 overexpression to observe the tumor volume and survival, and the CD4+ T cell subgroups were detected by flow cytometry. TIPE2 was lower in the OTSCC tissues than the corresponding oral mucosa, which was correlated with T stage, N stage, TNM stage, and differentiation of patients. Patients with TIPE2-positive expression had worse prognosis and lower expression of FoxP3+ Treg cells than the negative ones. Furthermore, TIPE2 overexpression curbed proliferation, invasion and migration of Tca8113 cells, while cell apoptosis was increased. Besides, TIPE2 suppressed the tumor growth and extended the survival of OTSCC mice, with the decreased proportion of FoxP3+ Treg cells in the spleen and tumor-infiltrated lymphocytes (TILs). The clinical results showed the down-regulation of TIPE2 in OTSCC tissues. Meanwhile TIPE2 overexpression affected OTSCC cells biological behavior in vitro, as well as exhibited strong tumor-growth suppressive effects in vivo, which may be a potential therapeutic target in OTSCC via regulating FoxP3+ Treg cells.

Selective anticancer activity of superparamagnetic iron oxide nanoparticles (SPIONs) against oral tongue cancer using in vitro methods: The key role of oxidative stress on cancerous mitochondria

Today, it has been proven that the nanoparticles such as superparamagnetic iron oxide nanoparticles (SPIONs) have widespread use in biomedical applications, for instance, in magnetic resonance imaging and targeted delivery of drugs. Despite many studies on SPIONs in diagnosing some diseases like cancer, it has not been investigated on the oral tongue squamous cell carcinoma (OTSCC) detection by the NPs. Hence, the present study has been designed to assess the in vitro cytotoxicity of SPIONs on the isolated mitochondria of OTSCC by mitochondrial tests. Isolated mitochondria were removed from the separated cancer and control tissues from the squamous cells of tango in male Wistar rats (6 or 8 weeks) and exposed to the different concentrations of SPIONs (30, 60, and 120 nM). A rise in the production of reactive oxygen species is one of the significant mechanisms of this study, followed by a collapse of mitochondrial membrane potential, the escape of mitochondrial cytochrome c, and mitochondrial swelling in the exposed isolated mitochondria of OTSCC with SPIONs. Furthermore, our results indicated that the exposure to the SPIONs reduced the activity of succinate dehydrogenase in complex II of the mitochondria obtained from cancerous oral tongue squamous. So the SPIONs can induce selective cytotoxicity on the OTSCC mitochondria without significant effects on the control mitochondria. Based on the results and further studies about in vivo experiments in this regard, it is concluded the SPIONs may be a hopeful therapeutic candidate for the treatment of OTSCC.

Lingual lymph nodes: Anatomy, clinical considerations, and oncological significance.

Lingual lymph nodes are an inconstant group of in-transit nodes, which are located on the route of lymph drainage from the tongue mucosa to the regional nodes in neck levels I and II. There is growing academic data on the metastatic spread of oral cancer, particularly regarding the spreading of oral tongue squamous cell carcinoma to lingual nodes. These nodes are not currently included in diagnostic and treatment protocols for oral tongue cancer. Combined information on surgical anatomy, clinical observations, means of detection, and prognostic value is presented. Anatomically obtained incidence of lingual nodes ranges from 8.6% to 30.2%. Incidence of lingual lymph node metastasis ranges from 1.3% to 17.1%. It is clear that lymph nodes that bear intervening tissues from the floor of the mouth should be removed to improve loco-regional control. Extended resection volume, which is required for the surgical treatment of lingual node metastasis, cannot be implied to every tongue cancer patient. As these lesions significantly influence prognosis, special efforts of their detection must be made. Reasonably, every tongue cancer patient must be investigated for the existence of lingual lymph node metastasis. Lymphographic tracing methods, which are currently implied for sentinel lymph node biopsies, may improve the detection of lingual lymph nodes.

Level IV neck dissection as an elective treatment for oral tongue carcinoma—a systematic review and meta-analysis

The purpose of our systematic review was to investigate the prevalence of level IV involvement and skip metastases in patients with clinically negative neck (cN0) oral tongue squamous cell carcinoma (OTSCC). The occurrence of occult metastases to lower levels in the neck (levels IV and V) or the development of an erratic distribution of cervical metastases ("skip metastases") that bypass the upper neck levels (levels I to III) and go directly to level IV or V challenges the role of supraomohyoid neck dissection in the treatment of OTSCC; therefore, controversy exists over including level IV cervical nodes during an elective neck dissection of OTSCC. Our search included all studies published from 1989 until January 2018 in the Cochrane Library, PubMed, EMBASE, and Web of Science. Abstracts and full-text articles that were deemed potentially relevant were screened. Data from the studies were extracted by using standardized tables, and a meta-analysis was conducted. In total, 3000 abstracts and 269 full text articles were screened, and 11 studies were included in this analysis. Among the 498 patients included, 16 had level IV involvement, representing involvement of 2.8%. The incidence for skip metastasis to level IV was low as well. We recommend elective neck dissection that includes levels I to III in selected patients with OTSCC and cN0 neck.

Molecular characterisation in tongue squamous cell carcinoma reveals key variants potentially linked to clinical outcomes.

Oral tongue squamous cell carcinoma (OTSCC) is a highly aggressive malignancy characterized by frequent recurrence, poor survival with relatively few therapeutic options due to the late diagnosis in many cases. Understanding the molecular pathways underlying OTSCC tumourigenesis and the discovery of diagnostic and/or prognostic biomarkers. We performed high-throughput mutational analysis of 44 OTSCC formalin-fixed paraffin-embedded (FFPE) cases using the Cancer Hotspots Panel (CHP) v2 on the Ion Torrent™platform. We determined the frequency of human papilloma virus (HPV) using PCR and Epstein bar virus (EBV) positivity using immunohistochemistry. As a control for EBV infection we screened matched non-tumourous tissues. Sequencing analysis identified missense, nonsense and frameshift mutations in TP53 (66%), PIK3CA (27%), CDKN2A (25%), EGFR (18%), and PTEN (14%). Interestingly, no significant associations were found between damaging mutations and clinicopathological data. A total of 10/44 of the OTSCC samples (23%) tested was positive for HPV18 DNA. OTSCC patients with positive HPV infection had worse overall survival compared to HPV-negative cases as determined by Kaplan-Meier survival (p= 0.023). Furthermore, EBNA1 expression showed a strong tumour-enriched expression pattern in 20 out of 21 samples (95%) in the epithelial compartments of the tissues analysed. Taken together, this study highlights that the two most common events in OTSCC are TP53 mutations and EBV positivity. Helping to understand the contribution of TP53 mutations and EBV infection events could serve as useful biomarkers for OTSCC.

Arguments to Support a Viral Origin of Oral Squamous Cell Carcinoma in Non-Smoker and Non-Drinker Patients.

In some western countries, an increasing incidence of oral squamous cell carcinoma (OSCC) has been observed in non-smoker non-drinker patients (NSND), mostly in women with HPV-negative OSCC. In the context of the unknown etiology and mechanisms of tumorigenesis of OSCC in NSND, we discuss data supporting the hypothesis of a viral origin not related to HPV. OSCC from NSND are characterized by an antiviral DNA methylation and gene expression signature. Based on the similar increasing incidence of oral tongue SCC (OTSCC) and oropharyngeal SCC (OPSCC) in young women and men respectively, we hypothesize that changes in sexual behaviors may lead to an increasing incidence of herpesvirus in the oral cavity, especially HSV-2, similarly to what has already been described in HPV-positive OPSCC. Because viral genome integration has not been detected in OSCC from NSND, a “hit and run” viral mechanism involving epigenome deregulation could therefore play a key role at early steps of oral carcinogenesis in this population of patients. In conclusion, epidemiological, clinical and molecular data supports a “hit and run” viral origin of OSCC from NSND.

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.