In vitro antimetastatic potential of pseudolaric acid B in HSC-3 human tongue squamous carcinoma cell line

OBJECTIVE

Pseudolaric acid B (PAB) is a novel diterpenoid derived from the traditional Chinese medicinal herb Cortex pseudolaricis that exerts anticancer, anti-inflammatory, and immunomodulatory properties. While the anticancer potential of PAB has been studied, its effects on metastasis have not been well-studied. This study aims to determine the inhibitory effects of PAB on HSC-3 human tongue squamous cell carcinoma (TSCC) cell line.

DESIGN

Cell viability and soft agar colony formation assays were conducted to assess cellular proliferation and in vitro tumorigenic capacity of TSCC cells, respectively. Additionally, wound healing, transwell migration, and invasion assays were conducted to monitor the aggressive behavior of TSCC cells. Furthermore, Western blotting analysis was conducted to reveal the signaling pathways involved in the modulation of epithelial-mesenchymal transition (EMT).

RESULTS

The migratory and invasive capacities of HSC-3 cells were suppressed by PAB irrespective of their proliferation states. PAB's effects on EMT involved upregulation of E-cadherin expression and downregulation of Twist; these were concomitantly accompanied by downregulated phosphorylation of epidermal growth factor receptor (EGFR).

CONCLUSIONS

PAB suppresses human TSCC in vitro by regulating Twist/E-cadherin through the EGFR signaling pathway. PAB may have potential as a candidate antimetastatic drug for TSCC treatment.

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

OBJECTIVE

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

DESIGN

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

RESULTS

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

CONCLUSION

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

Melatonin inhibits tongue squamous cell carcinoma: Interplay of ER stress-induced apoptosis and autophagy with cell migration

Tongue squamous cell carcinoma (TSCC) occupies a high proportion of oral squamous cell carcinoma. TSCC features high lymph node metastasis rates and chemotherapy resistance with a poor prognosis. Therefore, an effective therapy strategy is needed to improve patient prognosis. Melatonin (MT) is a natural indole compound shown to have anti-tumor effects in several cancers. This study focused on the role and mechanism of MT in TSCC cells. The results of the study suggest that MT could inhibit cell proliferation in CRL-1623 cells. Western blot analysis showed the down-regulate of cyclin B1 and the up-regulate P21 protein by MT. MT was also shown to down-regulate the expression of Zeb1, Wnt5A/B, and β-catenin protein and up-regulate E-cadherin to inhibit the migration of CRL-1623 cells. MT also promoted the expression of ATF4, ATF6, Bip, BAP31 and CHOP in CRL-1623 cells leading to endoplasmic reticulum stress, and induced autophagy and apoptosis in CRL-1623 cells. Western blots showed that MT could promote the expression of Bax, LC3, and Beclin1 proteins and inhibit the expression of p62. We screened differentially expressed long non-coding RNAs (lncRNAs) in MT-treated cells and found that the expression of MALAT1 and H19 decreased. Moreover, MT inhibited tumor growth in nude mice inoculated with CRL-1623 cells. These results suggest that MT could induce autophagy, promote apoptosis, and provide a potential natural compound for the treatment of TSCC.

MicroRNA expression as a prognostic biomarker of tongue squamous cell carcinoma (TSCC): a systematic review and meta-analysis

BACKGROUND

Recent studies have indicated that microRNA (miRNA) expression in tumour tissues has prognostic significance in Tongue squamous cell carcinoma (TSCC) patients. This study explored the possible prognostic value of miRNAs for TSCC based on published research.

METHODS

A comprehensive literature search of multiple databases was conducted according to predefined eligibility criteria. Data were extracted from the included studies by two researchers, and HR results were determined based on Kaplan‒Meier curves according to the Tierney method. The Newcastle‒Ottawa Scale (NOS) and GRADE (Grading of Recommendations Assessment, Development, and Evaluation) pro-GDT were applied to assess the quality of all studies. Publication bias was estimated by funnel plot, Egger's rank correlation test and sensitivity analysis.

RESULTS

Eleven studies (891patients) were included, of which 6 reported up-regulated miRNAs and 7 mentioned down-regulated miRNAs. The pooled hazard ratio (HR) from the prognostic indicator overall survival (OS) was 1.34 (1.25-1.44), p < 0.00001, indicating a significant difference in miRNA expression between TSCC patients with better or worse prognosis.

CONCLUSION

MiRNAs may have high prognostic value and could be used as prognostic biomarkers of TSCC.

A preliminary study of IgG4 expression and its prognostic significance in oral squamous cell carcinoma

BACKGROUND

IgG4, which plays a pivotal role in the progression of phenotypically diverse tumors, serves as a prognostic marker because of its influence on cancer immunity. Nevertheless, the functions of IgG4 in tongue squamous cell carcinoma (TSCC) remained to be identified.

METHODS

To evaluate the significance of IgG4 expression in TSCC, we performed immunohistochemical analysis of patients with TSCC (n = 50) to evaluate the correlation of IgG4 expression with patients' clinicopathological features and prognoses.

RESULTS

Higher IgG4 expression detected in TSCC tissues was associated with the less advanced mode of invasion (Yamamoto-Kohama [YK] 1-3) (P = 0.031) and with well-differentiated TSCC (P = 0.077). Kaplan-Meier analyses revealed that the higher IgG4 expression group exhibited better prognosis indicated by overall survival (OS) (P = 0.04) and recurrence-free survival (RFS) (P = 0.016). Univariate analysis of OS indicated that IgG4 expression was associated with longer OS (P = 0.061), and multivariate analysis of RFS revealed that IgG4 expression served as an independent prognostic factor for longer RFS (P = 0.005).

CONCLUSION

These results indicate that relatively higher IgG4 levels serve as a favorable prognostic factor for TSCC.

[Establishment and verification of a prognostic nomogram for survival of tongue squamous cell carcinoma patients who underwent cervical dissection]

OBJECTIVE

To evaluate the prognostic significance of inflammatory biomarkers, prognostic nutritional index and clinicopathological characteristics in tongue squamous cell carcinoma (TSCC) patients who underwent cervical dissection.

METHODS

The retrospective cohort study consisted of 297 patients undergoing tumor resection for TSCC between January 2017 and July 2018. The study population was divided into the training set and validation set by 7 :3 randomly. The peripheral blood indices of interest were preoperative neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), systemic inflammation score (SIS) and prognostic nutritional index (PNI). Kaplan-Meier survival analysis and multivariable Cox regression analysis were used to evaluate independent prognostic factors for overall survival (OS) and disease-specific survival (DSS). The nomogram's accuracy was internally validated using concordance index, receiver operating characteristic (ROC) curve, area under the curve (AUC), calibration plot and decision curve analysis.

RESULTS

According to the univariate Cox regression analysis, clinical TNM stage, clinical T category, clinical N category, differentiation grade, depth of invasion (DOI), tumor size and pre-treatment PNI were the prognostic factors of TSCC. Multivariate Cox regression analysis revealed that pre-treatment PNI, clinical N category, DOI and tumor size were independent prognostic factors for OS or DSS (P < 0.05). Positive neck nodal status (N≥1), PNI≤50.65 and DOI > 2.4 cm were associated with the poorer 5-year OS, while a positive neck nodal status (N≥1), PNI≤50.65 and tumor size > 3.4 cm were associated with poorer 5-year DSS. The concordance index of the nomograms based on independent prognostic factors was 0.708 (95%CI, 0.625-0.791) for OS and 0.717 (95%CI, 0.600-0.834) for DSS. The C-indexes for external validation of OS and DSS were 0.659 (95%CI, 0.550-0.767) and 0.780 (95%CI, 0.669-0.890), respectively. The 1-, 3- and 5-year time-dependent ROC analyses (AUC = 0.66, 0.71 and 0.72, and AUC = 0.68, 0.77 and 0.79, respectively) of the nomogram for the OS and DSS pronounced robust discriminative ability of the model. The calibration curves showed good agreement between the predicted and actual observations of OS and DSS, while the decision curve confirmed its pronounced application value.

CONCLUSION

Pre-treatment PNI, clinical N category, DOI and tumor size can potentially be used to predict OS and DSS of patients with TSCC. The prognostic nomogram based on these variables exhibited good accurary in predicting OS and DSS in patients with TSCC who underwent cervical dissection. They are effective tools for predicting survival and helps to choose appropriate treatment strategies to improve the prognosis.

Integrated bioinformatics analysis of SEMA3C in tongue squamous cell carcinoma using machine-learning strategies

Tongue squamous cell carcinoma (TSCC) is an aggressive oral cancer with a high incidence of metastasis and poor prognosis. We aim to identify and verify potential biomarkers for TSCC using bioinformatics analysis. To begin with, we examined clinical and RNA expression information of individuals with TSCC from the Gene Expression Omnibus (GEO) database. Differential expression analysis and functional analysis were conducted. Multiple machine-learning strategies were next employed to screen and determine the hub gene, and receiver operating characteristic (ROC) analysis was used to assess diagnostic value. Semaphorin3C (SEMA3C) was identified as a critical biomarker, presenting high diagnostic accuracy for TSCC. In the validation cohorts, SEMA3C exhibited high expression levels in TSCC. The high expression of SEMA3C was a poor prognostic factor in TSCC by the Kaplan-Meier curve. Based on the Gene Ontology (GO) analysis, SEMA3C was mapped in terms related to cell adhesion, positive regulation of JAK-STAT, positive regulation of stem cell maintenance, and positive regulation of NF-κB activity. Single-cell RNA sequencing (ScRNA-seq) analysis showed cells expressing SEMA3C were predominantly tumor cells. Then, we further verified that SEMA3C had high expression in TSCC clinical samples. In addition, the knockdown of SEMA3C suppressed the proliferation, migration, and invasion of TSCC cells in vitro. This study is the first to report the involvement of SEMA3C in TSCC, suggesting that upregulated SEMA3C could be a novel and critical potential biomarker for future predictive diagnostics, prevention, prognostic assessment, and personalized medical services in TSCC.

Regulating Lipid Metabolism via Mitochondrial Dynamics in Tongue Squamous Cell Carcinoma Cancer Stem Cells

BACKGROUND

Cancer stem cells (CSCs) are a sub-population of cancer cells present in many kinds of malignant tumors that have the potential for self-proliferation and differentiation. These cells have been demonstrated as the main cause of tumor recurrence and metastasis. Strong evidence indicates that CSCs prefer reprogrammed fatty acid β-oxidation over oxidative phosphorylation for sustaining energy supply. Although mitochondrial dynamics participate in the regulation of cancer stemness, the correlation between the inhibition of mitochondrial fission and the regulation of lipid metabolism in CSCs remains poorly understood.

METHODS

The human tongue squamous cell carcinoma (TSCC) cell lines CAL27 and SAS were used to obtain the CSCs by 3D Spheroid Culture. Then,western blot methods, RT-PCR and flow cytometry analysis were used to identify the TSCC CSCs. Next, Immunofluorescence method, transmission electron microscopy detection and western blot methods were used to evaluate the mitochondrial morphology and the quantity of lipid droplets (LDs). Lastly, lipidomic analysis was applied to explored the lipidomic alterations of TSCC CSCs with different mitochondrial morphology.

RESULTS

Here, we show that the quantity of lipid droplets containing intracellular triglyceride (TG) can be decreased by regulating mitochondrial morphology. Lipidomic analysis using ultraperformance liquid chromatography-mass spectrometry (UPLC-MS) also compared alterations in lipid metabolites in tongue squamous cell carcinoma (TSCC) CSCs, TSCC cells (non-CSCs), and CSCs with different mitochondrial morphology. Discriminant lipids of statistical significance were successfully annotated, including phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), sphingomyelins (SMs), triacylglycerols (TGs), phosphatidylglycerols (PGs), phosphatidylserines (PSs), lysophosphatidylcholines (LPCs), and lysophosphatidylethanolamines (LPEs).

CONCLUSION

This study provides a deeper insight into the alterations of lipid metabolism associated with TSCC CSCs, non-CSCs and CSCs regulated by mitochondrial dynamics and thus serves as a guide toward novel targeted therapies.

The role of unconventional lymph node metastasis in neck recurrence among patients with tongue cancer

OBJECTIVES

Statistics on the rate of unconventional lymph node metastases (ULNM) at the time of one-stage radical surgery in tongue cancer patients. To assess whether an extended neck dissection group with additional removal of ULNs has a lower rate of neck recurrence compared to the traditional neck dissection group.

MATERIALS AND METHODS

A total of 336 patients with TSCC who underwent radical surgery were recruited and underwent traditional or extended neck dissection. Compared to traditional neck dissection, the aim of extended neck dissection is designed to additional resect ULNs.

RESULTS

In total, 180 patients underwent extended neck dissection, while 156 underwent traditional neck dissection. The incidence of ULNM was 11.67% (21/180) in patients treated with extended neck dissection. The incidence of ipsilateral neck recurrence was 9.49% and 0.56% in patients who underwent traditional and extended neck dissection, respectively (p = 0.0001).

CONCLUSIONS

Extended neck dissection is effective for preventing neck recurrence in TSCC patients with ULNs.

CLINICAL RELEVANCE

ULNM may be the main cause of neck recurrence after neck dissection in patients with tongue cancer. A better prognosis may be achieved by additional resection of ULNs on the basis of traditional neck dissection.

Brucea javanica oil inhibits tongue squamous cell invasion and metastasis by regulating miR-138-EZH2 pathway

Tongue squamous cell carcinoma (TSCC) is one of the most common malignant tumors of head and neck. Its incidence is on the rise, and the proportion of young patients is gradually increasing, which is prone to tumor recurrence and metastasis. At present, there is no effective method to completely treat TSCC. Studies have shown that brucea javanica oil (BJO) has good antitumor activity against lung cancer and gastrointestinal tumors, but its therapeutic effect on TSCC is not clear. We have previously confirmed that oleic acid, the main component of BJO, can induce apoptosis of TSCC and reduce its invasion and metastasis ability. However, the anticancer effect and mechanism of BJO in TSCC remain unclear. In order to further explore the effects of BJO on the biological characteristics of TSCC cells, we studied the effects of different concentrations of BJO on the migration, invasion ability and epithelial mesenchymal transition (EMT) progression of TSCC cells and the possible mechanisms through in vitro experiments. We found that BJO could inhibit the invasion and metastasis of TSCC and up-regulate miR-138. After BJO treatment, the expression of E-cad was significantly increased, while the expression of EZH2, Slug, p-ERK1/2 and Vimentin was significantly decreased. EZH2 is a miR-138 target gene involved in TSCC. BJO inhibits TSCC invasion and metastasis by regulating the miR-138-EZH2 pathway. In vivo experiments have also well demonstrated the targeting effect of this pathway. This study provides a new therapeutic strategy for the treatment of TSCC.

WAVE3 Facilitates the Tumorigenesis and Metastasis of Tongue Squamous Cell Carcinoma via EMT

Wiskott-Aldrich syndrome protein family verprolin-homologous domain-containing protein 3 (WAVE3) is reported as an oncogene regulating cell proliferation and motility in multiple malignancies, while its role in tongue squamous cell carcinoma (TSCC) remains unknown. This study aimed to explore the expression and mechanism of WAVE3 in TSCC. We enrolled 64 TSCC patients admitted between June 2013 and February 2014 and collected their cancerous and adjacent normal tissues to determine WAVE3 expression by immunohistochemistry. The correlation of WAVE3 expression with TSCC patients' pathological characteristics was analyzed. Then, a 7-year follow-up was conducted to observe the value of WAVE3 in evaluating patient outcomes. In addition, human TSCC SCC9, SCC25, and CAL27 cells were purchased and detected by Cell Counting Kit-8 (CCK-8), Transwell, and scratch-wound assays for their proliferation, invasion, and migration capacities, while real-time quantitative PCR (qRT-PCR) and Western blotting were utilized to quantify WAVE3 and epithelial-mesenchymal transition (EMT)-related protein expression, respectively. The most active cell lines were selected to be infected with lentiviral vectors that silenced WAVE3 (named WAVE3-sh group) and overexpressed WAVE3 cDNA (named WAVE3-OE group) to observe the impacts of interfering WAVE3 expression on TSCC cell biological behavior. The positive expression of WAVE3 in TSCC tissue was found to be obviously enhanced and predominantly located in the cytoplasm. In addition, close correlations were identified between WAVE3 and T staging, clinical staging, lymphatic metastasis, distant metastasis, and differentiation degree (P < 0.05). Increased WAVE3 expression predicted an elevated risk of death, as indicated by the follow-up analysis (P < 0.05). SCC9 was selected for subsequent experiments among various TSCC cell lines studied because it showed the most potent ability to proliferate, invade, and migrate (P < 0.05). Silencing WAVE3 expression in SCC9 cells decreased cell proliferation, invasion, migration, and EMT-related protein expression (P < 0.05), while increasing WAVE3 expression promoted SCC9 viability. WAVE3, which was highly expressed in TSCC, promoted EMT in tumor cells and accelerated their proliferation, invasion, and migration, which might provide a new theoretical basis for molecular targeted therapy of TSCC in the future.

Significant association of Yamamoto-Kohama classification and pathological depth of invasion with cervical lymph node metastasis in early-stage tongue squamous cell carcinoma (Stage I/II)

Background/purpose

Tongue squamous cell carcinoma (SCC) has a poor prognosis due to a high rate of cervical lymph node metastasis (CLNM). We aimed to determine clinicopathological features related to the prediction of CLNM in tongue carcinomas (Stage Ⅰ/Ⅱ).

Materials and methods

Data from 89 patients with tongue SCC (Stage I/II) were analyzed retrospectively. Patients were treated only with partial glossectomy and not with chemotherapy or radiotherapy until CLNM was observed. No cervical lymph node metastasis survival (NCLNMS) was estimated using the Kaplan-Meier method. The difference in NCLNMS between the groups with and without CLNM was compared using the log-rank test. The Cox regression model was used to estimate hazard ratios and the associated 95% confidence interval.

Results

Clinical T2, clinical and pathological depth of invasion (cDOI and pDOI, respectively) > 5 mm, Yamamoto-Kohama (YK)-4c, tumor budding ≥5, worst pattern of invasion -4/5, muscle invasion, perineural invasion, and grade of differentiation 3 were found to be significant CLNM risk factors.

Conclusion

CLNM was observed in 25.8% of early-stage tongue carcinomas (Stage I/II). YK-4c and pDOI >5 mm were the most important CLNM risk factors identified. Close follow-up is needed after partial glossectomy when patients with tongue SCC have other risk factors, particularly YK-4c and pDOI >5 mm.

FDFT1 repression by piR-39980 prevents oncogenesis by regulating proliferation and apoptosis through hypoxia in tongue squamous cell carcinoma

AIM

Tongue squamous cell carcinoma (TSCC) is one of the most aggressive tumors whose underlying molecular mechanism remains elusive. Previous studies have identified piR-39980, a non-coding RNA, as a tumour suppressor or oncogene in different malignancies and the cholesterogenic protein, Farnesyl-Diphosphate Farnesyltransferase 1 (FDFT1) playing critical roles in cancer. The present study investigates the role of piR-39980, and its target FDFT1, in regulating the malignancy of TSCC.

MAIN METHODS

We performed qRT-PCR to determine the expression of FDFT1, piR-39980 and validated FDFT1 as a target of piR-39980 by dual luciferase assay. Then, to investigate the role of FDFT1 overexpression and piR-39980's inhibitory effect on FDFT1 in TSCC oncogenesis, we carried out MTT, migration, ROS estimation, and flow cytometric cell cycle assays. In addition to the above experiments, we also carried out flow cytometric apoptosis assay, chromatin condensation, γ-H2AX accumulation, and phalloidin staining assays upon overexpression and silencing of piRNA to unveil its mechanism of actions in TSCC malignancy.

KEY FINDINGS

FDFT1 promotes the oncogenesis of TSCC cells. Further, transient overexpression of piR-39980 significantly inhibited proliferation, migration, ROS generation, and colony formation and increased DNA damage and chromatin condensation causing cell death by repressing FDFT1. We conjectured that FDFT1 repression induces hypoxia, which slows DNA repair and accumulates damaged DNA, causing death of TSCC cells.

SIGNIFICANCE

Our study showed FDFT1 acts as an oncogene in TSCC, unlike other cancers, whose repression by a piRNA could prevent oncogenesis by regulating proliferation and apoptosis through hypoxia. This study reveals novel gene-regulatory mechanistic insights into TSCC oncogenesis.

HALP score based on hemoglobin, albumin, lymphocyte and platelet can predict the prognosis of tongue squamous cell carcinoma patients

Objective

The preoperative hemoglobin, albumin, lymphocyte, and platelet (HALP) score, a comprehensive marker of nutritional and immunological status, has been found to be robust for tumor prognosis prediction. Here, we evaluated the use of HALP in the prognostic prediction of tongue squamous cell carcinoma (TSCC).

Study design

Patients with TSCC were retrospectively recruited from the years 2009-2019. Patient clinicopathological characteristics, along with preoperative blood parameters, were recorded on admission, and the cut-off HALP value was determined by X-tile software. Kaplan-Meier curves and Cox regression analyses were used to evaluate the predictive value of HALP for patient overall survival (OS) and disease-free survival (DFS).

Results

A total of 339 TSCC patients were enrolled. The optimal HALP threshold was 56 and the patients were divided into two groups according to their scores. The Kaplan-Meier analysis showed that patients in the high-HALP group experienced longer OS (p = 0.007) and DFS (p = 0.006) than those in the low-HALP group. Multivariate analysis showed that elevated HALP (p = 0.038) was an independent predictor of OS, while age (p = 0.008), T stage (p < 0.001), N stage (p = 0.020), and degree of tumor differentiation (p < 0.001) were risk factors.

Conclusion

The findings showed that the preoperative HALP score was an independent predictor of prognosis in patients with TSCC.

Accuracy of Magnetic Resonance Imaging in Detecting Tumor Depth of Invasion in Squamous Cell Carcinoma of the Tongue: A Systematic Review

Objective

The objective of the study was to detect the accuracy of Magnetic Resonance Imaging (MRI) in assessing tumor depth of invasion (DOI) in squamous cell carcinoma (SCC) of the tongue.

Material and Methods

The electronic search of PubMed (including MEDLINE), COCHRANE CENTRAL and Google Scholar search engine for articles published from January 1, 2000, to September 31, 2021, was conducted and also searched the lists of references of relevant articles and reviews for studies involving patients with squamous cell carcinoma of the tongue.

Results

A total of 5362 articles were retrieved in the initial search. After the initial search process, 13 full-text articles were reviewed. Out of these 13 articles, seven met the inclusion criteria and were thus included in this systematic review.

Conclusion

The MRI-determined DOI based on T1-weighted sequences increases with increasing T stage. There is the highest correlation between the MRI-derived DOI and the histopathological DOI with increasing T stage. Therefore, MRI provides satisfactory diagnostic accuracy for measuring tumor DOI and, thus, may be considered a predictor of tumor stage.

The pattern and spread of invasion can predict late cervical lymph node metastasis in early tongue squamous cell carcinoma

To determine the predictive indexes of late cervical lymph node metastasis in early tongue squamous cell carcinoma (TSCC). We retrospectively analyzed the cases of 25 patients with stage I/II TSCC who had undergone surgical treatment without elective neck dissection. We evaluated the relationships between clinicopathologic factors and the occurrence of late cervical lymph node metastasis. Of the 25 cases, metastasis to the cervical lymph nodes was observed in nine cases (36.0%). The clinicopathological factors associated with late cervical lymph node metastasis were the mode of invasion (MOI, p = 0.032), depth of invasion (DOI, p = 0.004), and perineural invasion (PNI, p = 0.040). A multivariate analysis revealed that only the DOI was an independent predictor of late cervical lymph node metastasis. The combination of the DOI and MOI or the PNI and MOI was significantly correlated with late cervical lymph node metastasis (p = 0.004 and p = 0.012, respectively). Our findings suggest that combinations of the MOI, DOI, and PNI could be used as an index for predicting late cervical lymph node metastasis in early TSCC.

Molecular signaling in cancer stem cells of tongue squamous cell carcinoma: Therapeutic implications and challenges

Head and neck squamous cell carcinoma is the seventh most common cancer worldwide with high mortality rates. Amongst oral cavity cancers, tongue carcinoma is a very common and aggressive oral cavity carcinoma. Despite the implementation of a multimodality treatment regime including surgical intervention, chemo-radiation as well as targeted therapy, tongue carcinoma shows a poor overall 5-year survival pattern, which is attributed to therapy resistance and recurrence of the disease. The presence of a rare population, i.e., cancer stem cells (CSCs) within the tumor, are involved in therapy resistance, recurrence, and distant metastasis that results in poor survival patterns. Therapeutic agents targeting CSCs have been in clinical trials, although they are unable to reach into therapy stage which is due to their failure in trials. A more detailed understanding of the CSCs is essential for identifying efficient targets. Molecular signaling pathways, which are differentially regulated in the CSCs, are one of the promising targets to manipulate the CSCs that would provide an improved outcome. In this review, we summarize the current understanding of molecular signaling associated with the maintenance and regulation of CSCs in tongue squamous cell carcinoma in order to emphasize the need of the hour to get a deeper understanding to unravel novel targets.

Oncologic safety of the pedicled submental island flap for reconstruction in oral tongue squamous cell carcinoma: An analysis of 101 cases

OBJECTIVE

To evaluate whether the pedicle submental island flap (SIF) can be safely used in the oral tongue squamous cell carcinoma (OTSCC) patients with pathologically node-positive (pN+) neck, especially pN+ at level I.

METHODS

Retrospectively, 101 OTSCC patients with SIF reconstruction were enrolled. Oncological outcomes included the total locoregional recurrence, the SIF related locoregional recurrence (SRLR) which referred to the local recurrence at flap and ipsilateral neck recurrence at level I, recurrence free survival (RFS), overall survival (OS), and disease specific survival (DSS).

RESULTS

Sixty-one patients were pathologically node-negative (pN0) and 40 were pN+. Thirteen patients experienced locoregional recurrence, of which 5 had a SRLR. The pN+ group had a significantly higher locoregional recurrence rate, lower 5-year RFS, OS and DSS than pN0 group (P < 0.05). Patients with pN0 had a significantly higher neck RFS when compared to those with pN+ either at level I (P = 0.005) or at other levels (P < 0.001). However, the neck RFS was similar between the two subgroups of pN+ (P = 0.550). Especially, patients with pN+ at level I had a significantly higher SRLR rate (P = 0.006) compared to those with pN0 at level I. Multivariate analysis showed that pN+ was an unfavorable factor for tumor recurrence and OS.

CONCLUSION

Our data did not support the use of SIF in OTSCC patients with pN+ neck at level I due to an significantly increased SRLR rate compared to those with pN0 neck at level I.

Cancer chemo-preventive role of grape seed oil and cisplatin as a combination adjuvant therapy in the treatment of tongue squamous cell carcinoma: A biological in-vitro study

OBJECTIVES

Grape seed oil (GSO) has recently gained popularity due to its anticancer properties. This study aimed to investigate the efficacy of combining cisplatin (CP) and GSO in tongue squamous cell carcinoma (TSCC) treatment.

METHODS

In this study, human tongue carcinoma cell line (HNO-97) was treated with CP and GSO alone or in combination. The effects of CP and GSO on cytotoxicity and cell cycle arrest were studied using the MTT assay and flowcytometry, respectively. The apoptotic markers, including p53 and caspase 8, were assessed using reverse-transcription polymerase chain reaction (RT-PCR), caspase 3 using immunohistochemistry, and the angiogenic marker vascular endothelial growth factor (VEGF) using enzyme-linked immunosorbent assay (ELISA).

RESULTS

The IC50 drug concentrations were found to be 16.4 ug/mL of GSO and 2.18 ug/mL of CP. When compared to the untreated control group, the percentage of S phase cells and apoptotic cells was significantly higher in the GSO, CP, and GSO/CP combination therapy groups. Furthermore, p53, caspase 8, caspase 3 expression were significantly upregulated in the GSO-and CP-treated groups, with evident upregulation with GSO/CP combination therapy. However, VEGF levels were significantly lower in the GSO-, CP-, and combined GSO/CP-treated groups.

CONCLUSIONS

GSO has both an apoptotic and antiangiogenic effect in the treatment of TSCC, suggesting a new strategy for phytochemical-based combination therapy.

Hsa_circ_0081069 facilitates tongue squamous cell carcinoma progression by modulating MAP2K4 expression via miR-634

It has been demonstrated that circular RNA (circRNA) is involved in the progression of tongue squamous cell carcinoma (TSCC). The aim of this study was to investigate the intrinsic mechanism of circ_0081069 in TSCC progression. The expression levels of circ_00081069, miR-634, and mitogen-activated protein kinase kinase 4 (MAP2K4) in TSCC tissues and cells were detected by quantitative real-time PCR (qRT-PCR). Cell counting kit 8 assay, Edu assay, and flow cytometry assay were used to detect cell proliferation and cell cycle distribution. Transwell assay was used to detect cell migration and invasion abilities. Western blot analysis was performed to detect the protein expression. Dual-luciferase reporter assay was used to detect the targeting relationships of circ_0081069, miR-634 and MAP2K4. Immunohistochemical staining was used to measure MAP2K4-positive cells in tissues. The effect of circ_0081069 silencing on tumor formation in TSCC in vivo was explored by xenograft tumor assay. Circ_0081069 was highly expressed in TSCC tissues and cells. Silencing of circ_0081069 inhibited cell proliferation, cell cycle progress, cell migration and invasion in vitro, as well as hindered tumor growth in vivo. Mechanistically, circ_0081069 targeted miR-634 to negatively regulate miR-634 expression, and inhibition of miR-634 was able to weaken the inhibitory effect of circ_0081069 knockdown on proliferation, migration, and invasion of TSCC cells. MiR-634 targeted MAP2K4 and negatively regulated MAP2K4 expression, and overexpression of miR-634 inhibited TSCC cell proliferation, migration, and invasion, while co-overexpression of MAP2K4 was able to reverse the effects of miR-634 in TSCC cells. Circ_0081069 is involved in the regulation of proliferation, cycle progress, migration, and invasion of TSCC cells through the miR-634/MAP2K4 axis and has the potential to serve as a diagnostic biomarker and therapeutic target.

Microfibril-associated protein 2 is activated by POU class 2 homeobox 1 and promotes tumor growth and metastasis in tongue squamous cell carcinoma

Tongue squamous cell carcinoma (TSCC) represents the most frequent malignancy of the oral cavity, characterized by a high metastasis rate and poor prognosis. Microfibril-associated protein 2 (MFAP2), as an extracellular matrix protein, has been found to drive tumor progression. The function and underlying mechanism of MFAP2 in TSCC remain unknown. The expression levels of MFAP2 were analyzed in tissue samples from 30 TSCC patients by real time-polymerase chain reaction and western blot assays. Our results revealed that the expression of MFAP2 mRNA and protein was upregulated in TSCC tissue samples compared with that in the matched para-carcinoma tissue samples. By performing in vitro gain-of-function or loss-of-function experiments and in vivo mouse xenograft experiments, we found that overexpression of MFAP2 induced proliferation and promoted transition from G1 to S phase of TSCC cells. Stronger invasive and migratory capabilities were observed in MFAP2-overexpressing TSCC cells. In contrast, knockdown of MFAP2 exhibited anti-proliferative, apoptosis-promoting and pro-migratory roles in TSCC cells. Knockdown of MFAP2 significantly inhibited xenograft tumor growth. Mechanistically, POU class 2 homeobox 1 (POU2F1) was recruited to the region of MFAP2 promoter and upregulates the expression of MFAP2. Silencing of MFAP2 effectively blocked the proliferation, migration, and invasion of TSCC cells caused by POU2F1 overexpression. Our results indicate that the role of MFAP2 in TSCC may attribute to transcriptional regulation of POU2F1.

Oral-specific microenvironments regulate cell behavior and anticancer drug sensitivity of tongue squamous cell carcinoma

Squamous cell carcinoma (SCC) is the most major malignant tumor of the tongue. The tongue exists at the air-liquid interface and is covered with saliva. In addition, the tongue constituent cells and tongue cancer are present under fluid flow stimulation due to the abundant capillary network and contraction of muscle tissue. Therefore, replicating both cell-cell interactions (the cellular microenvironment) and the aforementioned physical microenvironment is very important for understanding the kinetics of tongue SCC. To elucidate the effects of the cellular and physical microenvironment on tongue SCC and to investigate the relationships between these factors, we developed a collagen cell disc, with double dish under a rotational culture method to generate cancer-stroma interactions and to create fluid flow stimulation. Mesenchymal cells, NIH-3T3 cells and tongue-derived fibroblasts influenced the proliferative potential. Extracellular signal-regulated kinase and p38 signaling were regulated either synergistically or independently by cellular interactions and fluid flow stimulation, depending on the SCC cell type. The cell-cell interactions and fluid flow stimulation independently, synergistically or contradictorily affected the behavior of tongue SCC. Fluid flow stimulation synergistically enhanced the antiproliferative effect of cis-diamminedichloroplatinum on tongue SCC cells, but mesenchymal cells abolished the synergistic antiproliferative effect related to fluid flow stimulation. In conclusion, a reconstructed model was established to investigate the cellular and physical microenvironments of tongue SCC in vitro. The newly established system is a promising model for the development of further regimes to treat general oral cancer.

The locoregional adiponectin and its synergistic antitumor effect with HIF-1α blockade in TSCC

Adiponectin (APN) is a kind of endogenous anti-tumor adipocytokine, which exerts its function by binding to its receptors (AdipoR1 and AdipoR2). However, hyperadiponectinemia is found in some pathophysiological processes without significant protective effect, which indicates the existence of APN resistance. Here, we aimed to investigate the locoregional expression of APN in tongue squamous cell carcinoma (TSCC) tissues, and to explore the potential regulatory mechanism of APN resistance under hypoxia. Consequently, we found that the protein expression of APN and AdipoR1, but not AdipoR2, was upregulated in the early stage of TSCC and after hypoxic treatment ex vivo and in vitro. Knockdown of HIF-1α decreased the level of APN and AdipoR1, and simultaneously, HIF-1α was identified as transcriptor of the APN. Intriguingly, a regenerative feedback of HIF-1α was unexpectedly detected after application of recombinant globular APN (gAPN), which most likely contributed to the APN resistance. Furthermore, HIF-1α blockade combined with gAPN has a prominent synergistic antitumor effect, which suggested an effective amelioration in APN resistance. In all, our study revealed the possible mechanism of APN resistance under hypoxia and provides a promising strategy of bi-target treatment with APN and HIF-1α for TSCC therapy.

An autophagy-related long non-coding RNA signature in tongue squamous cell carcinoma

BACKGROUND

Tongue squamous cell carcinoma (TSCC) is the most common oral cancer with a poor prognosis. At present, there is not any systematic study on autophagy-related long non-coding RNA (lncRNA) to predict the survival of patients with TSCC.

MATERIAL AND METHODS

In this research, the cohort of TSCC patients were obtained from The Cancer Genome Atlas (TCGA) database. Univariate and multivariate Cox regression analysis showed that ten lncRNAs related to autophagy AC010326.3, AL160006.1, AL122010.1, AC139530.1, AC092747.4, AL139287.1, MIR503HG, AC009318.2, LINC01711, and LINC02560 are significantly correlated with prognosis. Based on these lncRNAs, a prognostic signature was established. This signature has an AUC value of 0.782, which accurately distinguishes patients of TSCC into high-risk and low-risk groups in different clinical hierarchical information (such as gender, age, etc.).

RESULTS

The clinical nomogram with autophagy-related lncRNA prognostic characteristics has a concordance index of 0.81, and accurately predicts the survival time at 1-year and 3-year of TSCC patients. Related functional enrichment results indicate that the pathways of the high-risk group are enriched on cancer and autophagy.

CONCLUSIONS

The autophagy-related lncRNA prognostic signature established in this study could accurately predict the prognosis of TSCC patients and may be a molecular biomarker and therapeutic target.

Comparison of survival outcomes between adolescent and young adults and older adults with tongue squamous cell carcinoma: a nationwide database study using the head and neck cancer registry of Japan

BACKGROUND

This study aimed to evaluate the prognostic outcome for adolescent and young adult (AYA) generation patients with tongue squamous cell carcinoma (TSCC).

METHODS

Data were obtained from the Head and Neck Cancer Registry of Japan, and patients who were newly diagnosed with TSCC from 2011 to 2014 were extracted. We compared the clinical parameter and survival of the ≤ 39 years old (AYA) patient group with the 40-79 (non-AYA) group. Propensity score matching (PSM) was used for survival analyses.

RESULTS

Our cohort included 2221 patients with TSCC. AYA and non-AYA groups consisted of 258 and 1963 patients, respectively. The AYA group has a larger proportion of females than the non-AYA group (P < 0.001). Following PSM, both overall and disease-specific survival of the AYA group was significantly longer than those of the non-AYA group (P = 0.009 and P = 0.04, respectively).

CONCLUSION

We demonstrated the survival superiority of AYA patients with TSCC compared to older adult patients. Therefore, our study results may reduce this anxiety by providing patients with appropriate information of prognosis for AYA patients with TSCC.

Selinexor assists vorinostat in inhibiting HDAC activity via promoting the accumulation of maspin in the nucleus of oral tongue squamous cell carcinoma cells

Oral tongue squamous cell carcinoma (OTSCC) is the most common oral cancer with a low overall survival rate, necessitating effective treatments. This study reports the anti-OTSCC effect of vorinostat and selinexor. OTSCC cell lines SCC-4 and SCC-25 were cultured to determine the effects of vorinostat and/or selinexor on cell survival, invasion, migration, and apoptosis. The transplanted tumor model of SCC-25 in nude mice was established to observe the therapeutic effects of vorinostat and/or selinexor. Western blotting was used to determine protein expressions in tumor cells. The results showed that histone deacetylase 1 (HDAC1) and exportin 1 (XPO1) were highly expressed, while nuclear maspin was expressed at a low rate in SCC-4 and SCC-25 compared to the normal tongue tissue. In vitro, both vorinostat and selinexor effectively inhibited cell viability, invasion, and migration, promoted cell apoptosis, down-regulated HDAC1, Matrix Metalloproteinase 2 (MMP2), and B cell leukemia/lymphoma 2 (Bcl-2), and up-regulated nuclear maspin and cleaved caspase 3. In vivo, both vorinostat and selinexor inhibited the growth of SCC-25-bearing tumors, down-regulated the expression of Ki67, HDAC1, MMP2, and Bcl-2, and promoted the expression of nuclear maspin and cleaved caspase 3. The combination of these two drugs exhibited synergistic effects both in vivo and in vitro. Our evidence shows that vorinostat combined with selinexor is an effective treatment for OTSCC. The mechanism may be that selinexor promotes the accumulation of maspin in the nucleus, an endogenous HDAC1 inhibitory protein to inhibit the HDAC1 activity of vorinostat and exert a synergistic anti-OTSCC effect.

Radiomics analysis of [18F]-fluoro-2-deoxyglucose positron emission tomography for the prediction of cervical lymph node metastasis in tongue squamous cell carcinoma

OBJECTIVES

This study aimed to create a predictive model for cervical lymph node metastasis (CLNM) in patients with tongue squamous cell carcinoma (SCC) based on radiomics features detected by [¹⁸F]-fluoro-2-deoxyglucose (¹⁸F-FDG) positron emission tomography (PET).

METHODS

A total of 40 patients with tongue SCC who underwent ¹⁸F-FDG PET imaging during their first medical examination were enrolled. During the follow-up period (mean 28 months), 20 patients had CLNM, including six with late CLNM, whereas the remaining 20 patients did not have CLNM. Radiomics features were extracted from ¹⁸F-FDG PET images of all patients irrespective of metal artifact, and clinicopathological factors were obtained from the medical records. Late CLNM was defined as the CLNM that occurred after major treatment. The least absolute shrinkage and selection operator (LASSO) model was used for radiomics feature selection and sequential data fitting. The receiver operating characteristic curve analysis was used to assess the predictive performance of the ¹⁸F-FDG PET-based model and clinicopathological factors model (CFM) for CLNM.

RESULTS

Six radiomics features were selected from LASSO analysis. The average values of the area under the curve (AUC), accuracy, sensitivity, and specificity of radiomics analysis for predicting CLNM from ¹⁸F-FDG PET images were 0.79, 0.68, 0.65, and 0.70, respectively. In contrast, those of the CFM were 0.54, 0.60, 0.60, and 0.60, respectively. The ¹⁸F-FDG PET-based model showed significantly higher AUC than that of the CFM.

CONCLUSIONS

The ¹⁸F-FDG PET-based model has better potential for diagnosing CLNM and predicting late CLNM in patients with tongue SCC than the CFM.

m6A modification-mediated BATF2 suppresses metastasis and angiogenesis of tongue squamous cell carcinoma through inhibiting VEGFA

The aim is to explore the underlying mechanism of basic leucine zipper ATF-like transcription factor 2 (BATF2) in tongue squamous cell carcinoma (TSCC). The expression of BATF2 in TSCC tissues and corresponding adjacent normal TSCC tissues, human TSCC cell lines (SCC-15 and CAL-27) and human normal tongue epithelial cells NTEC was detected. Then, SCC-15 cells with stable BATF2 knockdown and CAL-27 cells with BATF2 overexpression were established to investigate the functional effect of BATF2 on TSCC. Thereafter, the effect of BATF2 on TSCC angiogenesis and BATF2 m6A methylation was also examined. BATF2 was significantly downregulated in TSCC tissues and cell lines, and BATF2 overexpression could suppress growth, metastasis and angiogenesis of TSCC. Mechanistically, vascular endothelial growth factor A (VEGFA) was identified as a downstream gene of BATF2, and it was confirmed that BATF2 suppressed growth, metastasis and angiogenesis of TSCC via inhibiting VEGFA. In addition, the N6-methyladenosine (m6A) modification of BATF2 mRNA mediated by METTL14 suppressed its expression in TSCC. METTL14/BATF2 axis could serve as a novel promising therapeutic candidate against angiogenesis for TSCC.

Investigating whether exosomal miR-205-5p derived from tongue squamous cell carcinoma cells stimulates the angiogenic activity of HUVECs by targeting AMOT

BACKGROUND

Although exosomal microRNAs (exo-miRNAs) regulate angiogenesis, they are not sufficient for the development of anti-vascular drugs for tongue squamous cell carcinoma (TSCC). miR-205-5p is an exo-miRNA that is highly expressed in the saliva of patients with oral SCC.

OBJECTIVE

We aimed to clarify the role and molecular mechanism of exosomal miR-205-5p in regulating TSCC angiogenesis.

METHODS

Effect of exosomes derived from TSCC cells on human umbilical vein endothelial cell (HUVEC) function was determined using the CCK-8, Transwell, Transwell-Matrigel, and Matrigel-based tube formation assays. Protein levels were detected by western blot. The binding between miR-205-5p and the 3'UTR of AMOT was verified using a luciferase reporter assay.

RESULTS

Exosomal miR-205-5p (exo-miR-205-5p) promoted the proliferation, migration, and invasion of HUVECs, increased the number of tubes formed by HUVECs, and increased the vascular endothelial growth factor receptor 2 levels in HUVECs. Exo-miR-205-5p downregulated the AMOT level in HUVECs. Results of the luciferase reporter assay showed that miR-205-5p could bind to the 3'UTR of AMOT. AMOT overexpression blocked the effect of exo-miR-205-5p on HUVEC functions.

CONCLUSION

Exo-miR-205-5p derived from TSCC regulates the angiogenic activity of HUVECs by targeting AMOT and might be a new molecular target for the development of anti-vascular drugs for TSCC.

Development and validation of novel nomograms to predict survival of patients with tongue squamous cell carcinoma

BACKGROUND

There is no unified standard to predict postoperative survival in patients with tongue squamous cell carcinoma (TSCC), hence the urgency to develop a model to accurately predict the prognosis of these patients.

AIM

To develop and validate nomograms for predicting overall survival (OS) and cancer-specific survival (CSS) of patients with TSCC.

METHODS

A cohort of 3454 patients with TSCC from the Surveillance, Epidemiology, and End Results (SEER) database was used to develop nomograms; another independent cohort of 203 patients with TSCC from the Department of Oral and Maxillofacial Surgery, First Affiliated Hospital of Zhejiang University School of Medicine, was used for external validation. Univariate and multivariate analyses were performed to identify useful variables for the development of nomograms. The calibration curve, area under the receiver operating characteristic curve (AUC) analysis, concordance index (C-index), net reclassification index (NRI), and decision curve analysis (DCA) were used to assess the calibration, discrimination ability, and clinical utility of the nomograms.

RESULTS

Eight variables were selected and used to develop nomograms for patients with TSCC. The C-index (0.741 and 0.757 for OS and CSS in the training cohort and 0.800 and 0.830 in the validation cohort, respectively) and AUC indicated that the discrimination abilities of these nomograms were acceptable. The calibration curves of OS and CSS indicated that the predicted and actual values were consistent in both the training and validation cohorts. The NRI values (training cohort: 0.493 and 0.482 for 3- and 5-year OS and 0.424 and 0.402 for 3- and 5-year CSS; validation cohort: 0.635 and 0.750 for 3- and 5-year OS and 0.354 and 0.608 for 3- and 5-year CSS, respectively) and DCA results indicated that the nomograms were significantly better than the tumor-node-metastasis staging system in predicting the prognosis of patients with TSCC.

CONCLUSION

Our nomograms can accurately predict patient prognoses and assist clinicians in improving decision-making concerning patients with TSCC in clinical practice.

Prognostic Value of Lymph Node Density Compared to Pre-operative Platelet-to-Lymphocyte Ratio and Neutrophil-to-Lymphocyte Ratio in Patients with Tongue Squamous Cell Carcinoma

Background

We aimed to investigate the prognostic significance of lymph node density (LND), and pre-operative neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) for outcome measuring in tongue squamous cell carcinoma (TSCC)' patients.

Methods

A total of 129 patients who underwent surgery for TSCC were enrolled in this retrospective study. LND and pre-operative NLR and PLR were used as outcome measures and their correlations with different clinicopathological features were examined.

Results

The cutoff values for NLR, PLR, and LND were obtained 1.21, 97.81, and 0.02, respectively, by receiver operating characteristic (ROC) curve approach. Only LND was found to be significantly associated with decreased overall survival (HR = 4.24; 95% CI 1.49-12.10; P = 0.007) and disease-free survival (HR = 3.48; 95% CI 1.43-8.45; P = 0.006) both in univariate and multivariate analyzes.

Conclusion

Based on the findings, the LND has superiority over pre-operative NLR and PLR in predicting outcomes for the patients with TSCC.

Recovery pattern analysis of swallowing function in patients undergoing total glossectomy and hemiglossectomy

OBJECTIVES

To investigate the recovery process of swallowing function and ascertain swallowing pattern in patients undergoing total glossectomy (TG).

MATERIALS AND METHODS

A cohort study was conducted in consecutive patients with tongue squamous cell carcinoma who received TG/hemiglossectomy (HG) from May 2017 to December 2019. Exposure factors included tongue resection range (HG and TG) and postoperative radiotherapy (PRT and non-PRT). The swallowing functions were evaluated by M.D. Anderson dysphagia inventory (MDADI), water swallow test (WST), and tongue pressure (TP) at pretreatment, 1, 4, 7, 12, 18 and 24 months postoperatively. Videofluoroscopy swallowing study (VFSS) was applied to analyze swallowing pattern of TG patients.

RESULTS

A total of 67 patients were enrolled, of which 17 underwent TG and 50 underwent HG. Both MDADI and TP of the TG and PRT group were lower than those of the HG and non-PRT group. TG patients had no evident improvement in MDADI and TP after surgery. There was a higher risk of swallowing unsafety with abnormal WST outcome in TG (P < 0.001, OR = 106.52) than that in HG. VFSS analysis identified prolonged oral and pharyngeal transit time, disorganized swallowing sequence, abnormal hyoid bone movement, and frequent invalid swallows in patients with TG. A shortened OTT (<5066.50 ms) and a larger pharyngeal constriction ratio (PCR > 0.31) were associated with increased risks of penetration and aspiration.

CONCLUSION

Postoperative swallowing pattern is a characteristic of severely impaired safety and efficacy in patients with TG. Impaired OTT and PCR are variables that should be examined when determining the need for rehabilitation treatment.

Conservative orthodontic treatment for severe pathologic migration following total glossectomy: A case report

Glossectomy combined with radiotherapy causes different levels of tongue function disorders and leads to severe malocclusion, with poor periodontal status in cancer survivors. Although affected patients require regular access to orthodontic care, special considerations are crucial for treatment planning. This case report describes the satisfactory orthodontic management for the correction of severe dental crowding in a 43-year-old female 6 years after treatment for tongue cancer with total glossectomy combined with radiotherapy, to envision the possibility of orthodontic care for oral cancer survivors. Extraction was performed to correct dental crowding and establish proper occlusion following alignment, after considering the possibility of osteoradionecrosis. Orthodontic mini-implants were used to provide skeletal anchorage required for closure of the extraction space and intrusion of the anterior teeth. The dental crowding was corrected, and Class I occlusal relationship was established after 36 months of treatment. The treatment outcome was sustained after 15 months of retention, and long-term follow-up was recommended.

Placental-Cadherin, a biomarker for local immune status and poor prognosis among patients with tongue squamous cell carcinoma

BACKGROUND

The prognostic and clinicopathological value of placental-Cadherin (CDH3) in multiple cancers is controversial. The diagnostic significance and functional mechanism of CDH3 in tongue squamous cell carcinoma (TSCC) have not been thoroughly investigated. This study aims to clarify the potential of CDH3 as biomarker for TSCC.

METHODS

Here, meta-analysis, bioinformatics, along wet-lab techniques were employed to evaluate the diagnostic, as well as the prognostic value of CDH3 in diverse types of cancers, especially TSCC. Meta-analysis was used to determine the influence of CDH3 on prognostic and clinicopathological features in numerous cancers. Molecular biology function was used to investigate the role of CDH3 in TSCC cells. The relationship of CDH3 with tumor-infiltrating immune cells (TIICs) in TSCC was assessed using CIBERSORT. Moreover, gene set enrichment analysis (GSEA) was done based on TCGA. Besides, the hub genes and associated cascades were uncovered based on gene co-expression with CDH3.

RESULTS

CDH3 upregulation correlated with worse overall survival and disease-free survival in various cancers. CDH3 was validated as an independent risk factor for HNSC and was linked to the onset of tumors, tumor stage, and infiltration depth. CDH3 silencing inhibited cell growth and induced apoptosis of the CAL-27 cell line. CDH3 expression level correlated with infiltration by macrophages, T cells, T cell regulatory cells (Tregs), and plasma cells in TSCC. GSEA revealed that CDH3 influences multiple cancer-associated cascades. Besides, CBX3, CCHCR1, along NFYC were identified as the core hub genes for CDH3.

CONCLUSION

We identified CDH3 as a pan-cancer gene with potential prognostic and diagnostic significance in various cancers, particularly in TSCC, where it is tumorigenic.

Isoprenylcysteine carboxyl methyltransferase promotes the progression of tongue squamous cell carcinoma via the K-Ras and RhoA signaling pathways

OBJECTIVE

This research investigated the biological role of isoprenylcysteine carboxyl methyltransferase (ICMT) in tongue squamous cell carcinoma (TSCC) progression meanwhile to explore the conceivable mechanism.

METHODS

The mRNA and protein expression were measured using real-time PCR and Western blot. Cell proliferation, apoptosis, cycle distribution, migration and invasion were evaluated by CCK-8 assay, flow cytometry, wound-healing assay and transwell assay. The anti-tumor activity of ICMT silencing was observed in nude mice.

RESULTS

Our results indicated that silencing of ICMT-mediated methylation effectively inhibited TSCC cells proliferation in vitro and reduced tumor growth in vivo. Moreover, ICMT knockdown also induced cell apoptosis and cell cycle arrest of both CAL-27 and SCC-4 cells. In addition, CAL-27 and SCC-4 cells migration and invasion were weakened by ICMT siRNA. Mechanistically, ICMT deficiency significantly decreased the K-Ras and RhoA membrane targeting localization, leading to the suppression of K-Ras- and RhoA-mediated downstream signaling in CAL-27 and SCC-4 cells.

CONCLUSIONS

Altogether, our findings identified a crucial role played by ICMT in the progression of TSCC and the potential mechanisms by which exerted its effects, indicating that targeting ICMT may represent a promising therapeutic strategy for TSCC.

5-Azacitidine and Trichostatin A induce DNA damage and apoptotic responses in tongue squamous cell carcinoma: An in vitro study

OBJECTIVE

The present in vitro study aims to investigate the potential use of epigenetic inhibitors as treatment modalities in tongue squamous cell carcinoma.

DESIGN

The human tongue squamous cell carcinoma cell line (CAL-27) was cultured and exposed to varying concentrations of 5-Azacitidine (5-Aza) or Trichostatin A (TSA) in the culture medium. The cell apoptosis was evaluated using Annexin V/PI by flow cytometry. To evaluate DNA damage response, γH2AX foci analysis was performed using immunofluorescence. Single cell gel electrophoresis (SCGE) was applied to measure DNA strand breaks. Gene expression was assessed by quantitative real-time PCR.

RESULTS

The results showed that 5-Aza and TSA had apoptotic effects on the SCC cell line at concentrations of 50-200 µM and 0.5-5 µM, respectively. Immunofluorescence analysis showed increased expression of γH2AX, the marker of DNA damage response after treatment of 5-Aza and TSA that was associated with increased DNA strand breaks. The expressions of urokinase plasminogen activator, its receptor and matrix metalloproteinase-2, were significantly reduced in TSA- and 5-Aza-treated cells.

CONCLUSIONS

Our results showed that 5-Aza and TSA increase apoptotic and DNA damage response in squamous cell carcinoma cell line while reducing the expression of tumor invasion genes that further indicating the potential therapeutic value of two epigenetic modifiers in squamous cell carcinoma.

Microbial community alteration in tongue squamous cell carcinoma

Tongue squamous cell carcinoma (TSCC) is the most common oral cavity malignancy. The role of the microbial community in TSCC development and progression is unclear. In the present study, 23 patients with TSCC were recruited. Tissue DNA was extracted from cancer and paracancerous normal tissues from all participants. Next-generation 16S rDNA amplicon sequencing and functional prediction were applied for taxonomic analysis. Alpha diversity measurements using the Shannon and Simpson diversity indexes indicated a significant increase in the microbiotic diversity of cancer samples (Shannon index: P = 0.001, Simpson index: P = 0.015); otherwise, no differences were found when using observed operational taxonomic units (OTUs) and Chao1 index (observed OTUs: P = 0.261, Chao1 index: P = 0.054). The dominant phyla of the microbiota included Bacteroidetes, Proteobacteria, Firmicutes, Actinobacteria, and Fusobacteria. Multivariate analysis of variance (Adonis) and nonparametric analysis of similarities (ANOSIM) based on unweighted unifrac distances demonstrated differences in the bacterial community structure between the two groups (P = 0.001 for Adonis, P = 0.001 for ANOSIM). Compared with the normal samples, Neisseria, Streptococcus, and Actinomyces levels decreased significantly in cancer samples. Co-occurrence network analysis implied that the bacterial community in cancer was more conserved than that in normal tissue. Matched-pair analysis of cancer and control samples revealed a significant alteration in the relative abundance of specific taxa. These findings will enrich our knowledge of the association between the oral microbial community and TSCC. Further experiments should investigate the potential carcinogenic mechanism of microbial community alterations in TSCC. KEY POINTS: • Microbial community role in tongue squamous cell carcinoma. • Significant alteration of microbiome found between cancer and normal tissues. • Microbial community alteration and potential carcinogenic mechanism.

BASP1 is up-regulated in tongue squamous cell carcinoma and associated with a poor prognosis

OBJECTIVE

To study the relationship between expression of brain acid soluble protein 1 (BASP1) in tongue squamous cell carcinoma (TSCC) tissue and the clinicopathological characteristics and prognosis of patients with TSCC.

METHODS

Western blotting was performed to detect BASP1 expression in fresh-frozen specimens of tumor tissue and adjacent normal tissue obtained from 6 patients with TSCC. Immunohistochemical methods were used to detect BASP1 expression in 100 paraffin-embedded specimens of TSCC tissue. The chi-square test was used to analyze the association between BASP1 expression and a variety of clinicopathological parameters. A Kaplan-Meier analysis and the Cox proportional hazard model were used to further evaluate the impact of BASP1 on patient survival.

RESULTS

The Oncomine database showed that BASP1 expression was increased in TSCC tissues. The PrognoScan and GEPIA databases suggested that a high level of BASP1 expression is related to a poor prognosis for patients with head and neck cancer. Experimental results showed that when compared to normal tissues adjacent to a cancer, BASP1 was more highly expressed in the TSCC tissues. Univariate and multivariate Cox regression analyses showed that BASP1 expression and the tumor's stage may be independent risk factors that affect the growth and prognosis of TSCC. A survival analysis showed that patients with a low level of BASP1 expression had a higher survival rate.

CONCLUSION

Overexpression of BASP1 was found to be associated with distant node metastasis and a poor prognosis among patents with TSCC. BASP1 could possibly serve as a molecular marker for diagnosing and treating the disease.

C-reactive protein promotes tongue squamous cell carcinoma chemoresistance by inhibiting the activation of caspase-3/9 via the CD64/AKT/mTOR pathway

Recent studies have shown that C-reactive protein (CRP) participates in multiple types of cancer development. Here, the aim of this study was to investigate the role of CRP in tongue squamous cell carcinoma (TSCC) chemoresistance. Immunohistochemical staining showed that CRP expression was upregulated in TSCC tissues from cisplatin-resistant patients compared with that in cisplatin-sensitive TSCC samples. The CRP expression level was positively correlated with that of the drug-resistant marker MDR1. Moreover, functional experiments showed that CRP increased cell viability and decreased cisplatin-induced apoptosis. CRP also increased the expression levels of MDR1 and Bcl-2 and decreased the expression level of Bax. Furthermore, CRP decreased the activity of caspase-3. Mechanistically, CRP could bind to Fcγ receptor I (FcγRI, also known as CD64) and activate the AKT/mTOR pathway to inhibit the activation of caspase-3/9, as shown by co-immunoprecipitation (Co-IP) assay and western blotting assays. In addition, CRP promoted tumour growth and decreased cleaved caspase-3/9 expression in BALB/c nude mice. Taken together, our findings indicate that CRP promotes TSCC chemoresistance by inhibiting the activation of caspase-3/9 via the FcγRI/AKT/mTOR pathway. Thus, CRP could potentially be considered as a therapeutic target for reducing TSCC chemoresistance.

EGCG inhibits growth of tumoral lesions on lip and tongue of K-Ras transgenic mice through the Notch pathway

Epigallocatechin-3-gallate (EGCG), the main active ingredient of green tea, exhibits low toxic side effect and versatile bioactivities, and its anti-cancer effect has been extensively studied. Most of the studies used cancer cell lines and xenograft models. However, whether EGCG can prevent tumor onset after cancer-associated mutations occur is still controversial. In the present study, Krt14-cre/ERT-Kras transgenic mice were developed and the expression of K-RasG12D was induced by tamoxifen. Two weeks after induction, the K-Ras mutant mice developed exophytic tumoral lesions on the lips and tongues, with significant activation of Notch signaling pathway. Administration of EGCG effectively delayed the time of appearance, decreased the size and weight of tumoral lesions, relieved heterotypic hyperplasia of tumoral lesions, and prolonged the life of the mice. The Notch signaling pathway was significantly inhibited by EGCG in the tumoral lesions. Furthermore, EGCG significantly induced cell apoptosis and inhibited the proliferation of tongue cancer cells by blocking the activation of Notch signaling pathway. Taken together, these results indicate EGCG as an effective chemotherapeutic agent for tongue cancer by targeting Notch pathway.

Association of CASC18/miR-20a-3p/TGFB2 ceRNA axis with occult lymph node metastasis in tongue squamous cell carcinoma

Background

Tongue squamous cell carcinoma (TSCC) ranks as the most prevalent malignancy in the oral cavity. TSCC patients with occult lymph node metastasis (OLNM) are thought to be at risk of worse outcome. However, regulatory mechanisms underlying OLNM remain less investigated.

Methods

In the present study, CASC18/miR-20a-3p/TGFB2 axis was identified and evaluated by bioinformatic and qRT-PCR analyses. Effects of CASC18 knockdown on cell migration and invasion were determined by wound healing and transwell assays. Western blot, ELISA, RNA pulldown and luciferase reporter assays were performed for mechanism verification.

Results

CASC18 was identified up-regulating in TSCC tumours, and especially in those from patients with OLNM. Importantly, we found higher CASC18 expression was positively correlated with the presence of OLNM and worse outcome of TSCC patients. Furthermore, we demonstrated that CASC18 knockdown repressed cell migration and invasion through inhibiting epithelial-mesenchymal transition, which could be partly rescued by miR-20a-3p inhibitor. Regarding the molecular mechanism, we further confirmed that CASC18 functioned as a ceRNA to sponge miR-20a-3p to enhanceTGFB2 expression and secretion.

Conclusion

In conclusion, we have reported a novel CASC18/miR-20a-3p/TGFB2 ceRNA axis in OLNM of TSCC. Our findings will contribute to a deeper understanding of the molecular mechanism of OLNM in TSCC, and facilitate the development of diagnostic methods for assisting treatment decision-making.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10020-021-00345-9.

P16-positive secondary tongue squamous cell carcinoma following allogeneic hematopoietic stem cell transplantation: A case report and literature review

As a method to improve the survival rate of patients with hematological malignancies, allogeneic hematopoietic stem cell transplantation (allo-HSCT) has increasingly been used for treatment. However, some potentially serious complications after allo-HSCT, including graft-versus-host disease, graft failure, infection, end-organ toxicity, and secondary malignancies, will determine the success of hematopoietic reconstitution. Here, we describe a case of a patient with p16-positive tongue squamous cell carcinoma (TSCC) following allo-HSCT. A 62-year-old man who had previously received allo-HSCT due to acute lymphocytic leukemia (AML) presented with erosions on the back of the tongue surrounded by multiple white patches, which were compatible with oral chronic graft-versus-host disease (cGVHD). During follow-up, a circular-like erosive lesion appeared on the right dorsal surface of the tongue. Biopsy of this lesion confirmed early invasive TSCC (T2N0M0). Partial glossectomy and tongue reconstruction were performed after cessation of immunosuppressants. Immunohistochemical (IHC) staining was positive for p16 and ki-67, suggesting a probable active human papillomavirus (HPV) infection. Six months after surgery, the patient showed no signs of metastasis or recurrence nor progression of oral GVHD.

Development of photocontrolled BRD4 PROTACs for tongue squamous cell carcinoma (TSCC)

The catalytic properties of small-molecule proteolysis targeting chimeras (PROTACs) may lead to uncontrolled degradation. Therefore, the main disadvantages of PROTACs are non-cancer specificity and relatively high toxicity, which limit the clinical application of PROTACs. The photocontrolled PROTACs (photoPROTACs) were proposed to overcome this issue, in which they can be triggered by ultraviolet A (UVA) or visible light to induce the degradation of the target protein. Herein, we designed several photoPROTACs to cause the degradation of bromodomain-containing protein 4 (BRD4) on-demand using 365 nm light. The representative compound N2 is proved to induce the degradation of BRD4 upon irradiation. Moreover, compound N2 was successfully applied in vivo to inhibit tumor growth in a zebrafish xenograft model of skin cancer tongue squamous cell carcinoma (TSCC) in a photocontrol manner.

MicroRNA-27a promotes tumorigenesis in tongue squamous cell carcinoma by enhancing proliferation, migration and suppressing apoptosis

BACKGROUND

Tongue squamous cell carcinoma (TSCC) is a major subtype of head and neck squamous cell carcinoma (HNSCC), which is an intractable cancer with a poor prognosis. Studies have shown that microRNAs (miRNAs) play an important role in TSCC biology. However, the expression and functions of miRNAs in TSCC remain unclear.

METHODS

The non-coding RNA profiles of TSCC were downloaded from the GEO database. WGCNA (Weighted gene co-expression network analysis) and differential expression miRNA (DE-miRNA) analyses were employed to identify key candidate miRNAs. miRNA expression was detected using RT-qPCR analysis. The target genes of key miRNAs were predicted. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed to explore the potential functions and pathways of key miRNA. miRNA inhibitor was transfected to detect the function of miRNA. The effect of miRNA deregulation on TSCC cell proliferation and apoptosis was investigated using MTS, Annexin V-FITC/PI double staining, and flow cytometry assays.

RESULTS

miR-27a was a key miRNA in TSCC, which was significantly up-regulated in both Cal-27 cells and malignant tissues from the TSCC patients. In addition, functional analysis showed that miR-27a was involved in the regulation of the MAPK, ERBB, and Jak-STAT signaling pathways. Moreover, RHOA and PRKACA were potential target genes of miR-27a, suggesting them as possible mediators of the tumor-promoting effect of miR-27a. Moreover, downregulation of miR-27a inhibited cell proliferation and facilitated cell apoptosis in Cal-27 cells.

CONCLUSION

Our findings strongly suggest that miR-27a could promote the tumorigenesis and development of TSCC, which makes it a potential new diagnostic marker and therapeutic target for TSCC.

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.

CCR7-CCL21 axis promotes the cervical lymph node metastasis of tongue squamous cell carcinoma by up-regulating MUC1

This study aims at investigating the potential role of MUC1 in CCR7-CCL21 axis-induced metastasis of tongue squamous cell carcinoma (TSCC). TSCC patients were selected for epidemiologic trends. The expression of CCR7 and MUC1 was detected via immunohistochemistry. SCC15 and CAL27 cells were induced by CCL21 and specific antibody to CCR7. Gene and protein expression was detected using qRT-PCR and western blotting. Migration and invasion capacities of TSCC cells were determined using wound healing and Transwell invasion assays. The male:female ratio of 78 patients was 1.6:1. Metastasis rate of cervical lymph nodes (CLNs) was 42.3%. CLN metastasis significantly correlated with T staging (P = 0.026), clinical staging (P = 0.024), and depth of invasion (DOI, P = 0.001). DOI significantly influenced CLN metastasis (P = 0.033, OR = 10.919) of TSCC, as did CCR7 (P = 0.041) and MUC1 (P = 0.026). The consistency of CCR7 and MUC1 expression was fairly good (Kappa = 0.683, P < 0.001). Reduced survival was significantly associated with higher expression of CCR7 (P = 0.039) and MUC1 (P = 0.030). CCL21 up-regulated MUC1 in SCC15 cells, which was inhibited when CCR7 was blocked. MUC1 positively correlated with TSCC cell migration and invasion. CCR7-CCL21 axis might promote CLN metastasis of TSCC by up-regulating MUC1. CCR7 and MUC1 show promise as potential biomarkers for TSCC treatment.

Silencing SHMT2 inhibits the progression of tongue squamous cell carcinoma through cell cycle regulation

Background

Serine hydroxymethyltransferase 2 (SHMT2) is a vital metabolic enzyme in one carbon metabolism catalyzing the conversion of serine to glycine, which has been reported to play a crucial role in the progression of tumors. However, its function in tongue squamous cell carcinoma (TSCC) remains unclear.

Methods

SHMT2 expression was analyzed using samples in online databases, and was assessed through immunohistochemistry staining of collected clinical specimens. The correlation between SHMT2 expression and the cell cycle was predicted through bioinformatic analysis, including weighted gene co-expression network analysis (WGCNA) and gene set enrichment analysis (GSEA). After transfection with siRNA, CCK8 assay, Edu staining, flow cytometry, trans-well assay, and wound healing experiments were performed to verify the functional role of SHMT2 in vitro. A stable cell line with SHMT2 silencing was established to detect the oncogenic function of SHMT2 in vivo.

Results

The expression of SHMT2 was up-regulated in TSCC tissues and cell lines compared with normal groups, and highly expressed SHMT2 significantly indicated a poorer clinical outcome for TSCC patients. Bioinformatic analysis found that high expression of SHMT2 was closely related with biologic process including cell cycle and cell cycle G1/S transition. Down regulating of SHMT2 significantly suppressed the proliferation, invasive and migrative ability of TSCC cells, and induced the prolongation of the G1 phase of the cell cycle in vitro. Furthermore, western blot showed that cell cycle-related regulators such as cyclin-dependent kinase 4 (CDK4) and cyclinD1 expression levels were decreased, while the expression levels of the cyclin-dependent kinase inhibitors p21^Cip1 and p27^Kip1 were increased after SHMT2 knockdown. Silencing SHMT2 in the HN6 cell line using short hairpin RNA also impeded tumor growth in vivo.

Conclusions

Overexpression of SHMT2 in TSCC indicated low survival rates, and was associated with aggressive behaviors of TSCC. It was also found to be involved in cell cycle regulation of TSCC cells. SHMT2 may serve as a novel prognostic indicator of TSCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01880-5.

HPV+ve/-ve oral-tongue cancer stem cells: A potential target for relapse-free therapy

The tongue squamous cell carcinoma (TSCC) is a highly prevalent head and neck cancer often associated with tobacco and/or alcohol abuse or high-risk human papillomavirus (HR-HPV) infection. HPV positive TSCCs present a unique mechanism of tumorigenesis as compared to tobacco and alcohol-induced TSCCs and show a better prognosis when treated. The poor prognosis and/or recurrence of TSCC is due to presence of a small subpopulation of tumor-initiating tongue cancer stem cells (TCSCs) that are intrinsically resistant to conventional chemoradio-therapies enabling cancer to relapse. Therefore, targeting TCSCs may provide efficient therapeutic strategy for relapse-free survival of TSCC patients. Indeed, the development of new TCSC targeting therapeutic approaches for the successful elimination of HPV+ve/-ve TCSCs could be achieved either by targeting the self-renewal pathways, epithelial mesenchymal transition, vascular niche, nanoparticles-based therapy, induction of differentiation, chemoradio-sensitization of TCSCs or TCSC-derived exosome-based drug delivery and inhibition of HPV oncogenes or by regulating epigenetic pathways. In this review, we have discussed all these potential approaches and highlighted several important signaling pathways/networks involved in the formation and maintenance of TCSCs, which are targetable as novel therapeutic targets to sensitize/eliminate TCSCs and to improve survival of TSCC patients.

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.

Importance of human papillomavirus infection in squamous cell carcinomas of the tongue in Guangdong Province, China

Objective

Methods

Results

Conclusion