Epithelial to mesenchymal transition in head and neck squamous cell carcinoma

Crosstalk between CAFs and tumour cells in head and neck cancer

Head and neck squamous cell carcinomas (HNSCCs) are amongst the most aggressive, complex, and heterogeneous malignancies. The standard of care treatments for HNC patients include surgery, radiotherapy, chemotherapy, or their combination. However, around 50% do not benefit while suffering severe toxic side effects, costing the individuals and society. Decades have been spent to improve HNSCC treatment outcomes with only limited success. Much of the research in HNSCC treatment has focused on understanding the genetics of the HNSCC malignant cells, but it has become clear that tumour microenvironment (TME) plays an important role in the progression as well as treatment response in HNSCC. Understanding the crosstalk between cancer cells and TME is crucial for inhibiting progression and treatment resistance. Cancer-associated fibroblasts (CAFs), the predominant component of stroma in HNSCC, serve as the primary source of extra-cellular matrix (ECM) and various pro-tumoral composites in TME. The activation of CAFs in HNSCC is primarily driven by cancer cell-secreted molecules, which in turn induce phenotypic changes, elevated secretive status, and altered ECM production profile. Concurrently, CAFs play a pivotal role in modulating the cell cycle, stemness, epithelial-mesenchymal transition (EMT), and resistance to targeted and chemoradiotherapy in HNSCC cells. This modulation occurs through interactions with secreted molecules or direct contact with the ECM or CAF. Co-culture and 3D models of tumour cells and other TME cell types allows to mimic the HNSCC tumour milieu and enable modulating tumour hypoxia and reprograming cancer stem cells (CSC). This review aims to provide an update on the development of HNSCC tumour models comprising CAFs to obtain better understanding of the interaction between CAFs and tumour cells, and for providing preclinical testing platforms of current and combination with emerging therapeutics.

Insights into metastatic roadmap of head and neck cancer squamous cell carcinoma based on clinical, histopathological and molecular profiles

The incidence of head and neck cancer (HNC), constituting approximately one in ten cancer cases worldwide, affects approximately 644,000 individuals annually. Managing this complex disease involves various treatment modalities such as systemic therapy, radiation, and surgery, particularly for patients with locally advanced disease. HNC treatment necessitates a multidisciplinary approach due to alterations in patients' genomes affecting their functionality. Predominantly, squamous cell carcinomas (SCCs), the majority of HNCs, arise from the upper aerodigestive tract epithelium. The epidemiology, staging, diagnosis, and management techniques of head and neck squamous cell carcinoma (HNSCC), encompassing clinical, image-based, histopathological and molecular profiling, have been extensively reviewed. Lymph node metastasis (LNM) is a well-known predictive factor for HNSCC that initiates metastasis and significantly impacts HNSCC prognosis. Distant metastasis (DM) in HNSCC has been correlated to aberrant expression of cancer cell-derived cytokines and growth factors triggering abnormal activation of several signaling pathways that boost cancer cell aggressiveness. Recent advances in genetic profiling, understanding tumor microenvironment, oligometastatic disease, and immunotherapy have revolutionized treatment strategies and disease control. Future research may leverage genomics and proteomics to identify biomarkers aiding individualized HNSCC treatment. Understanding the molecular basis, genetic landscape, atypical signaling pathways, and tumor microenvironment have enhanced the comprehension of HNSCC molecular etiology. This critical review sheds light on regional and distant metastases in HNSCC, presenting major clinical and laboratory features, predictive biomarkers, and available therapeutic approaches.

Curcumol Inhibits the Progression of Hepatocellular Carcinoma by Regulating the Expression of hsa_circ_0028861

Background: Hsa_circ_0028861, a newly discovered serum exosome circular RNA (circRNA), is greatly reduced in the serum of patients with hepatocellular carcinoma (HCC). However, the exact role of hsa_circ_0028861 in the progression of liver cancer is still unknown. Materials and Methods: Thirty patients with HCC were enrolled in this study. Hsa_circ_0028861 expression was explored via real-time polymerase chain reaction (PCR) assay. The influence of curcumol on HCC cells were tested using CCK-8 assay, 5-ethynyl-2'-deoxyuridine (EdU) staining, cell wound healing assay, and migration assay, respectively. The related mechanism was determined by Western blot. A xenograft tumor model was constructed, and mice were administrated with curcumol. Results: The expression of hsa_circ_0028861 in tumor tissues was elevated of patients with HCC and in HCC cells. Curcumol treatment decreased the expression of hsa_circ_0028861 in HCC cells. Curcumol treatment could largely suppress the viability, proliferation, and migration of HCC cells by reducing hsa_circ_0028861 expression and mediating the epithelial-mesenchymal transition (EMT) process. Curcumol also effectively restrained tumor growth in the HCC mice model. Conclusions: Curcumol exerted an inhibitory role in HCC progression by downregulating hsa_circ_0028861 expression and mediating the EMT process, which provides evidence for screening new therapeutic targets and drug therapies for HCC treatment.

Cholesterol depletion induces mesenchymal properties in oral squamous cell carcinoma cell line

BACKGROUND

Cholesterol in cell membranes is crucial for cell signaling, adhesion, and migration. Membranes feature cholesterol-rich caveolae with caveolin proteins, playing roles in epithelial-mesenchymal transition and cancer progression. Despite elevated cholesterol levels in tumors, its precise function and the effects of its depletion in oral squamous cell carcinoma remain unclear. The aim of this study was to evaluate the influence of cholesterol depletion in oral squamous cell carcinoma cell line and epithelial-mesenchymal transition process.

METHODS

Cholesterol depletion was induced on SCC-9 cells by methyl-β-cyclodextrin and cell viability, proliferation, apoptosis, and colony formation capacities were evaluated. Gene and protein expressions were evaluated by reverse transcription polymerase chain reaction (RT-qPCR) and Western Blot, respectively, and cell sublocalization was assessed by immunofluorescence.

RESULTS

Cholesterol depletion resulted in alteration of oral squamous cell carcinoma cell morphology at different concentrations of methyl-β-cyclodextrin, as well as decreased cell proliferation and viability rates. Analysis of CAV1 transcript expression revealed increased gene expression in the treated SCC-9 during the 24 h period, at different concentrations of methyl-β-cyclodextrin: 5 , 7.5, 10, and 15 mM, in relation to parental SCC-9. CAV1 protein expression was increased, with subsequent dose-dependent decrease. A statistically significant difference was observed in samples treated with 5 mM of methyl-β-cyclodextrin (p = 0.02, Kruskal-Wallis test). The immunofluorescence assay showed lower cytoplasmic and membrane labeling intensity in the treated samples for CAV1.

CONCLUSION

These findings indicate the modulation of cholesterol as a possible mechanism underlying the regulation of these molecules and activation of epithelial-mesenchymal transition in oral squamous cell carcinoma.

The significance of Hippo pathway protein expression in oral squamous cell carcinoma

Introduction

The Hippo pathway consists of mammalian sterile 20-like kinase 1/2 (MST1/2), large tumor suppressor 1/2 (LATS1/2), and yes-associated protein (YAP)1. Herein, we present the first report on the significance of major Hippo pathway protein expression in oral squamous cell carcinoma (OSCC).

Methods

The analyses included oral epithelial dysplasia (OED, n = 7), carcinoma in situ (CIS, n = 14), and oral squamous cell carcinoma (OSCC, n = 109).

Results

Cytoplasmic expression of MST1, LATS1, and LATS2 was low in OED, CIS, and OSCC. The cytoplasmic expression of MST2 was high in OED (5/7 cases), CIS (9/14 cases), and poorly differentiated OSCC (8/8 cases) but was low/lost in a proportion of differentiated OSCC (60/101 cases). The expression of YAP1 was associated with differentiation; low YAP expression was significantly more frequent in well-differentiated OSCC (35/71 cases), compared to moderately and poorly differentiated OSCC (11/38 cases). An infiltrative invasion pattern was associated with a high expression of MST2 and high expression of YAP1. The high expression of YAP1 was associated with features of epithelial-to-mesenchymal transition (EMT), such as the loss of E-cadherin and high expression of vimentin, laminin 5, and Slug. High expression of protein arginine methyltransferase (PRMT) 1 or 5, which positively regulates YAP activity, was associated with the high expression of YAP1 (p < 0.0001).

Conclusion

Among the major Hippo pathway proteins, MST2 displayed a distinctive expression pattern in a significant proportion of differentiated OSCC, suggesting a possible differential role for MST2 depending on the course of OSCC progression. A high YAP1 expression may indicate aggressive OSCC with EMT via PRMTs at the invasive front.

Antrodia salmonea suppresses epithelial-mesenchymal transition/metastasis and Warburg effects by inhibiting Twist and HIF-1α expression in Twist-overexpressing head and neck squamous cell carcinoma cells

ETHNOPHARMACOLOGICAL RELEVANCE

Antrodia salmonea (AS), linked to the genus Taiwanofungus, is a medicinal fungus, and exhibits anti-inflammatory, anti-oxidant, and tumor inhibiting properties.

AIM OF THE STUDY

In this study, we investigated the metabolic reprogramming and anti-metastasis/epithelial-mesenchymal transition (EMT) effects of AS exposure in Twist-overexpressing head and neck squamous cell carcinoma (HNSCC, OECM-1 and FaDu-Twist) cells.

MATERIALS AND METHODS

MTT assay, Western blot, migration/invasion assay, immunofluorescence, glucose uptake assay, lactate assay, oxygen consumption rate (OCR)/Extracellular acidification rate (ECAR) assay, Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry (LC-ESI-MS), and qRT-PCR experimental techniques were used to evaluate the therapeutic potential of AS treatment in HNSCC cells.

RESULTS

This study showed that AS exhibits anti-EMT and anti-metastatic effects as well as metabolic reprogramming in Twist-overexpressing HNSCC cells. AS exposure inhibited Twist and hypoxia-inducible factor-1α (HIF-1α) protein and/or mRNA expression in Twist-overexpressing OECM-1 and FaDu-Twist cells. AS markedly suppressed EMT by enhancing the expression of E-cadherin; while the N-cadherin was suppressed. Furthermore, glucose uptake and lactate accumulation, together with HIF-1α-regulated glycolysis genes were diminished by AS in OECM-1 cells. AS decreased the ECAR, and enhanced the OCR together with basal respiration, ATP production, maximal respiration, and spare respiratory capacity under normoxia and hypoxia (CoCl2) in OECM-1 cells. There was a marked reduction in the level of glycolytic intermediate's; while TCA cycle metabolites were increased by AS treatment in OECM-1 cells.

CONCLUSIONS

We concluded that AS treatment suppresses EMT/metastasis and Warburg effects through Twist and HIF-1α inhibition in Twist-overexpressing HNSCC cells.

Ovarian squamous cell carcinoma associated with teratoma: a report of six cases with genomic analysis

Ovarian squamous cell carcinoma (SCC), particularly the sarcomatoid variant, arising from teratoma is a rare malignant tumour with unfavourable clinical outcomes. Its molecular genetic alterations have not been well-documented to date. This study aims to characterise the molecular features and to provide potential therapeutic targets in this rare entity. We analysed the clinicopathological and immunohistochemical features of six primary ovarian SCC. These cases were subject to targeted next-generation sequencing to detect genomic features. We found that all six ovarian SCC (four conventional and two sarcomatoid SCC) were associated with mature cystic teratomas. Patient 3 (FIGO stage IIIa) and Patient 4 (stage IIb) died of disease at 10 and 11 months, respectively. The remaining patients (three with stage I and one with IIc) including the two with sarcomatoid SCC, were alive with no evidence of disease at 28-72 months. All patients showed PD-L1 expression (tumour proportion score: range 10-78%, median 41%; combined positive score: range 12-85, median 42) and a high tumour mutation burden (range 13.4-25.7 mutations/Mb, median 16.5). The most frequently recurrent mutations included PIK3CA (4/6), TP53 (4/6), TERT promoter (4/6), CDKN2A (3/6). Mutations in homologous recombination repair pathway genes (BLM, ATM, BRCA1, BRIP1 and ATM) were found in 5/6 patients. The sarcomatoid SCC shared a similar mutational profile with conventional SCC, and no recurrent genetic mutations exclusively in sarcomatoid SCC were identified. Our study suggests the potential benefits of immune checkpoint inhibitors and/or PARP inhibitors in patients with primary ovarian SCC on account of PD-L1 expression and genomic features. Ovarian sarcomatoid SCC may be clonally related to the conventional SCC. A multiple-institutional, clinical and molecular study will consolidate these findings in the future.

Discovery of the first-in-class potent and isoform-selective human carbonic anhydrase III inhibitors

Considering the unrecognised physio-pathological role of human carbonic anhydrase III (hCA III), a structure-based drug design was set up to identify the first-in-class potent and selective inhibitors of this neglected isoform. hCA III targeting was planned considering a unique feature of its active site among the other hCA isoforms, i.e. the Leu198/Phe198 substitution which interferes with the binding of aromatic/heterocyclic sulfonamides and other inhibitors. Thus, new aliphatic primary sulfonamides possessing long and flexible (CH2)nSO2NH2 moieties were designed to coordinate the zinc(II) ion, bypassing the bulky Phe198 residue. They incorporate 1,2,3-triazole linkers which connect the tail moieties to the sulfonamide head, enhancing thus the contacts at the active site entrance. Some of these compounds act as nanomolar and selective inhibitors of hCA III over other isoforms. Docking/molecular dynamics simulations were used to investigate ligand/target interactions for these sulfonamides which might improve our understanding of the physio-pathological roles of hCA III.

Role of Akt/Protein Kinase B in Cancer Metastasis

Metastasis is a critical step in the process of carcinogenesis and a vast majority of cancer-related mortalities result from metastatic disease that is resistant to current therapies. Cell migration and invasion are the first steps of the metastasis process, which mainly occurs by two important biological mechanisms, i.e., cytoskeletal remodelling and epithelial to mesenchymal transition (EMT). Akt (also known as protein kinase B) is a central signalling molecule of the PI3K-Akt signalling pathway. Aberrant activation of this pathway has been identified in a wide range of cancers. Several studies have revealed that Akt actively engages with the migratory process in motile cells, including metastatic cancer cells. The downstream signalling mechanism of Akt in cell migration depends upon the tumour type, sites, and intracellular localisation of activated Akt. In this review, we focus on the role of Akt in the regulation of two events that control cell migration and invasion in various cancers including head and neck squamous cell carcinoma (HNSCC) and the status of PI3K-Akt pathway inhibitors in clinical trials in metastatic cancers.

Unleashing the pathological imprinting of cancer in autoimmunity: Is ZEB1 the answer?

The intriguing scientific relationship between autoimmunity and cancer immunology have been traditionally indulged to throw spotlight on novel pathological targets. Understandably, these "slowly killing" diseases are on the opposite ends of the immune spectrum. However, the immune regulatory mechanisms between autoimmunity and cancer are not always contradictory and sometimes mirror each other based on disease stage, location, and timepoint. Moreover, the blockade of immune checkpoint molecules or signalling pathways that unleashes the immune response against cancer is being leveraged to preserve self-tolerance and treat many autoimmune disorders. Therefore, understanding the common crucial factors involved in cancer is of paramount importance to paint the autoimmune disease spectrum and validate novel drug candidates. In the current review, we will broadly describe how ZEB1, or Zinc-finger E-box Binding Homeobox 1, reinforces immune exhaustion in cancer or contributes to loss of self-tolerance in auto-immune conditions. We made an effort to exchange information about the molecular pathways and pathological responses (immune regulation, cell proliferation, senescence, autophagy, hypoxia, and circadian rhythm) that can be regulated by ZEB1 in the context of autoimmunity. This will help untwine the intricate and closely postured pathogenesis of ZEB1, that is less explored from the perspective of autoimmunity than its counterpart, cancer. This review will further consider several approaches for targeting ZEB1 in autoimmunity.

Targeted inhibition of eIF5Ahpu suppresses tumor growth and polarization of M2-like tumor-associated macrophages in oral cancer

Eukaryotic initiation factor 5A2 (eIF5A2) is overexpressed in many types of cancer, and spermidine-mediated eIF5A hypusination (eIF5Ahpu) appears to be essential to most of eIF5A's biological functions, including its important role in regulating cancer cell proliferation, epithelial-mesenchymal transition (EMT), and cancer stem cell (CSC) properties as well as immune cell functions. Here we investigated the role of eIF5Ahpu in the growth of oral squamous cell carcinoma cells (OSCCs) and OSCC-induced polarization of M2-like tumor-associated macrophages (TAMs). TCGA dataset analysis revealed an overall upregulation in the mRNA expression of eIF5A2 and several key enzymes involved in polyamine (PA) metabolism in HNSCC, which was confirmed by Western blot and IHC studies. Blocking eIF5Ahpu by GC-7 but not the upstream key enzyme activities of PA metabolism, remarkably inhibited cell proliferation and the expression of EMT- and CSC-related genes in OSCC cells. In addition, blocking eIF5Ahpu robustly inhibited OSCC-induced M2-like TAM polarization in vitro. More Importantly, blocking eIF5Ahpu dramatically retarded tumor growth and infiltration/polarization of M2-like TAM in a syngeneic orthotopic murine tongue SCC model. Thus, eIF5Ahpu plays dual functions in regulating tumor cell growth and polarization of M2-TAMs in OSCC.

Application of single-cell RNA sequencing in head and neck squamous cell carcinoma

Single-cell RNA sequencing has been broadly applied to head and neck squamous cell carcinoma (HNSCC) for characterizing the heterogeneity and genomic mutations of HNSCC benefiting from the advantage of single-cell resolution. We summarized most of the current studies and aimed to explore their research methods and ideas, as well as how to transform them into clinical applications. Through single-cell RNA sequencing, we found the differences in tumor cells' expression programs and differentiation tracks. The studies of immune microenvironment allowed us to distinguish immune cell subpopulations, the extensive expression of immune checkpoints, and the complex crosstalk network between immune cells and non-immune cells. For cancer-associated fibroblasts (CAFs), single-cell RNA sequencing had made an irreplaceable contribution to the exploration of their differentiation status, specific CAFs markers, and the interaction with tumor cells and immune cells. In addition, we demonstrated in detail how single-cell RNA sequencing explored the HNSCC epithelial-to-mesenchymal transition (EMT) model and the mechanism of drug resistance, as well as its clinical value.

Aberrant Expression of Claudins in Head and Neck Carcinomas and Their Prognostic and Therapeutic Value: A Narrative Review

Head and neck carcinomas have been associated with poor prognosis. Recent studies have highlighted the role of claudins' expression in tumors throughout the body, and their prognostic and therapeutic role. Understanding the role of claudins and how their expression affects the progression of carcinomas in the head and neck region may allow for advances in the prognosis and management of this type of cancer. Several studies have highlighted the aberrant expression of the proteins in carcinomas in this region. Specifically, the overexpression of claudin-1 and downregulation of claudins-4, -7, and -17 have been linked with poor survival in oral squamous cell carcinoma patients. In laryngeal squamous cell carcinoma, increased levels of claudins-1 and reduced levels of claudins-3, -8, and -11 have been linked with poor outcomes. Targeting these proteins has shown promising outcomes as therapeutic in preclinical studies. However, studies remain extremely limited in nasal and hypopharyngeal carcinomas. In this review, we survey the available literature describing the aberrant expression of various claudins in carcinomas in this region, while highlighting their potential prognostic and therapeutic value. Then, we describe some molecular mechanisms involved in the aberrant expression of claudins and how they can be utilized as therapeutic targets.

BMP-induced non-canonical signaling is upregulated during autophagy-mediated regeneration in inflamed mesothelial cells

Previously, we showed that after Freund's adjuvant-induced peritonitis, rat mesothelial cells regain their epithelial phenotype through mesenchymal-epithelial transition (MET) accompanied by autophagy. Since bone morphogenetic proteins (BMPs) are well-known MET-inducers, we were interested in the potential expression of BMPs and BMP-induced pathways. Although mesothelial cells expressed lower amounts of BMP7, its level in the peritoneal cavity and mesothelial synthesis of BMP4 were significantly increased during inflammation. BMPR1A and BMPR2 were also significantly expressed. Expression of transforming growth factor beta-activated kinase (TAK1) and c-Jun NH2-terminal kinases (JNK1-JNK2) were more intense than that of phosphorylated Mothers Against Decapentaplegic homolog 1/5 (p-SMAD1/5), confirming that the non-canonical pathway of BMPs prevailed in our model. JNK signaling through B-cell lymphoma-2 (Bcl-2) can contribute to Beclin-1 activation. We demonstrated that TAK1-JNK-Bcl-2 signaling was upregulated simultaneously with the autophagy-mediated regeneration. A further goal of our study was to prove the regenerative role of autophagy after inflammation. We used a specific inhibitor, bafilomycin A1 (BafA1), and found that BafA1 treatment decreased the expression of microtubule-associated protein 1A/1B-light chain 3 (LC3B) and resulted in morphological signs of cell death in inflamed mesothelial cells indicating that if autophagy is arrested, regeneration turns into cell death and consequently, mesothelial cells die.

In vitro and in vivo anti-tumor activity of Coenzyme Q0 against TWIST1-overexpressing HNSCC cells: ROS-mediated inhibition of EMT/metastasis and autophagy/apoptosis induction

HNSCC (Head and Heck Squamous Cell Carcinoma) is a reasonably prevalent cancer with a high mortality rate. In this study, we tried to examine the anti-metastasis and apoptosis/autophagy actions of Coenzyme Q₀ (CoQ₀, 2,3-dimethoxy-5-methyl-1,4-benzoquinone), a derivative of Antrodia camphorata in HNCC TWIST1 overexpressing (FaDu-TWIST1) cells as well as in vivo tumor xenograft mice model. Using fluorescence based cellular assays, western blot and nude mice tumor xenografts, we determined that CoQ₀ effectively reduced cell viability and displayed rapid morphological changes in FaDu-TWIST1 cells compared to FaDu cells. Non/sub-cytotoxic concentrations of CoQ₀ treatment reduces the cell migration by downregulating TWIST1 and upregulating E-cadherin. Apoptosis produced by CoQ₀ was mostly related with caspase-3 activation, PARP cleavage, and VDAC-1 expression. The FaDu-TWIST1 cells treated with CoQ₀ exhibits autophagy-mediated LC3-II accumulation and acidic vesicular organelles (AVOs) formation. Pre-treatment with 3-MA and CoQ effectively prevented CoQ₀-induced cell death and CoQ₀-triggered autophagy in FaDu-TWIST cells as a death mechanism. CoQ₀ induces ROS production in FaDu-TWIST1 cells and NAC pre-treatment significantly reduces anti-metastasis, apoptosis, and autophagy. Likewise, ROS-mediated AKT inhibition regulates CoQ₀-induced apoptosis/autophagy in FaDu-TWIST1 cells. In vivo studies exhibit, CoQ₀ effectively delays and reduces the tumor incidence and burden in FaDu-TWIST1-xenografted nude mice. Current findings display, CoQ₀ exhibits a novel anti-cancer mechanism hence, it might be appropriate for anticancer therapy, and a new potent drug for HNSCC.

Tumour-stroma ratio is a valuable prognostic factor for oral tongue squamous cell carcinoma

OBJECTIVE

The objectives of this study were to estimate the prognostic value of the tumour-stroma ratio (TSR) and tumour budding (TB) in oral tongue squamous cell carcinoma (OTSCC) and to establish a reliable model to predict the outcome of OTSCC patients.

METHODS

A total of 103 patients surgically treated at our hospital were enrolled in this study. Chi-square tests, Kaplan-Meier analyses and Cox proportional hazards regression models were performed for statistical analysis.

RESULTS

Fifty-six patients were categorized as stroma-rich, and 47 patients were categorized as stroma-poor. Only pathological grade was associated with the TSR (p = 0.017). Kaplan-Meier analysis showed that stroma-rich, high-intensity budding and high risk groups were associated with worse prognosis. The Cox regression model showed that the TSR was an independent risk factor for OTSCC patients prognosis, and the high risk group was also related to poor prognosis (p < 0.05). TB was significantly associated with poor prognosis but was not an independent risk factor.

CONCLUSIONS

We found that patients in the stroma-rich group had a worse long-term prognosis. The TSR is an independent risk factor for OTSCC patients' outcome. In addition, a risk model that combined the TSR and TB proved to be valuable for predicting OTSCC patients' outcome.

Cholesterol depletion affects caveolin-1 expression, migration and invasion of oral tongue squamous cell carcinoma cell lines

INTRODUCTION

Cholesterol is a key lipid molecule within cell membranes. This is especially true in cavelolas, invaginated membrane nanodomains, which present the protein caveolin-1 (CAV-1). It is important to note that this structure is involved in many cell signalling pathways. Additionally, high cholesterol is seen in different tumor types but little is known in regards to oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to evaluate the influence of cholesterol depletion on primary (SCC-25) and metastatic (HSC-3) OTSCC cell lines.

MATERIALS AND METHODS

Cell membrane fluidity, cell viability, gene and protein expression of CAV-1 and of epithelial-mesenchymal transition (EMT) markers, cell migration in Myogel and invasion-myoma assay were evaluated after cholesterol depletion with methyl-β-cyclodextrin (MβCD - 7.5, 10 or 15 mM) RESULTS: Decreased cell viability and increased membrane fluidity of SCC-25 cells was seen with cholesterol depletion but cell viability was less affected and there was no effect on membrane fluidity in HSC-3. Cholesterol depletion also decreased CAV-1 at 6 h but increased it after 24 h.; both epithelial and mesenchymal EMT genes were upregulated after 6 h, followed by downregulation at 24 h in SCC-25. In HSC-3, CAV-1 was downregulated, and E-cadherin gene (ECAD) was upregulated at 6 h. Only the protein β-catenin in SCC-25 was affected, and cell migration of both cell lines was decreased, affecting SCC-25 more intensely. The invasive capacity within human myoma organotypic model was increased in SCC-25 and decreased in HSC-3.

CONCLUSION

Cholesterol depletion affects CAV-1 and ECAD inversely. This affect also depends on cell type since the invasive capacity was augmented in primary cells while decreased in metastatic cells.

Extract of Ficus septica modulates apoptosis and migration in human oral squamous cell carcinoma cells

According to the alarming statistical analysis of global cancer, there are over 19 million new diagnoses and more than 10 million deaths each year. One such cancer is the oral squamous cell carcinoma (OSCC), which requires new therapeutic strategies. Ficus septica extract has been used in traditional medicine to treat infectious diseases. In this study, we examined the anti-proliferative effects of an extract of F. septica bark (FSB) in OSCC cells. Our results showed that FSB caused a concentration-dependent reduction in the viability of SCC2095 OSCC cells, as determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, and was less sensitive to fibroblasts. In addition, FSB induced apoptosis by activating caspases, accompanied by the modulation of Akt/mTOR/NF-κB and mitogen-activated protein kinase signaling. Moreover, FSB increased reactive oxygen species generation in a concentration-dependent manner in SCC2095 cells. Furthermore, FSB inhibited cell migration and modulated the levels of the cell adhesion molecules including E-cadherin, N-cadherin, and Snail in SCC2095 cells. Pinoresinol, a lignan isolated from FSB, showed antitumor effects in SCC2095 cells, implying that this compound might play an important role in FSB-induced OSCC cell death. Taken together, FSB is a potential anti-tumor agent against OSCC cells.

Overexpression of E-Cadherin Is a Favorable Prognostic Biomarker in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

Oral squamous cell carcinoma (OSCC) is characterized by poor survival, mostly due to local invasion, loco-regional recurrence, and metastasis. Given that the weakening of cell-to-cell adhesion is a feature associated with the migration and invasion of cancer cells, different studies have explored the prognostic utility of cell adhesion molecules such as E-cadherin (E-cad). This study aims to summarize current evidence in a meta-analysis, focusing on the prognostic role of E-cad in OSCC. To find studies meeting inclusion criteria, Scopus, Web of Science, EMBASE, Medline, and OpenGrey databases were systematically assessed and screened. The selection process led to 25 studies, which were considered eligible for inclusion in the meta-analysis, representing a sample of 2553 patients. E-cad overexpression was strongly associated with longer overall survival (OS) with Hazard Ratio (HR)  = 0.41 95% confidence interval (95% CI) (0.32-0.54); p < 0.001 and disease-free survival with HR 0.47 95% CI (0.37-0.61); p < 0.001. In terms of OS, patients with tongue cancer experienced better survivability when expressing E-cad with HR 0.28 95% CI (0.19-0.43); p < 0.001. Globally, our findings indicate the prognostic role of the immunohistochemical assessment of E-cad in OSCC and its expression might acquire a different role based on the oral cavity subsites.

Capparis zeylanica L. root extract promotes apoptosis and cell cycle arrest, inhibits epithelial-to-mesenchymal transition and triggers E-cadherin expression in breast cancer cell lines

Capparis zeylanica L. is a climbing shrub distributed in Indian subcontinent and Mediterranean region. Almost all parts of the plant are used in folk medicine and traditional practices to treat several human ailments. The present study was aimed to investigate the role of C. zeylanica L. root extract in preventing cancerous cells growth and proliferation, as well as promoting apoptosis and cell cycle arrest in MDA-MB-231 and MCF-7 breast cancer cells. Methanolic extract of C. zeylanica L. (MECz) was prepared and characterized by LC-ESI-MS/MS analysis. In vitro cytotoxicity and anti-proliferative activity of MECz was evaluated by MTT assay, while cell viability, apoptosis and cell cycle progression by Muse Cell analyzer. Furthermore, the mRNA and protein expressions of EMT markers were assessed using qRT-PCR and western blotting techniques, respectively. The MECz was found to be rich in phenolic compounds including chlorogenic acid, 6-gingerol, and certain triterpenes like ursolic acid etc. The apparent anti-metastasis activity of MECz was evident from IC50 value of 19.12 and 24.22 μg/mL, respectively, on MDA-MB-231 and MCF-7 cells in MTT assay. An absolute decrease in cell viability (78.1-53.4% and 89.9-49.0%), augmented apoptosis (90.98-48.25% and 88.25-47.70%) and S phase, G2/M phase cell cycle arrest was found by MECz treatment on MDA-MB-231 and MCF-7 cells. The gene expression studies revealed that MECz could significantly (p < 0.001) regulate the expression of EMT markers such as snail, slug, zeb-1, twist-1, fibronectin, vimentin and E-cadherin at molecular level. These findings demonstrate that C. zeylanica L. root extract inhibits breast cancer cells growth and proliferation through regulating the expression of key EMT marker genes and proteins. Thus, MECz may be suggested as a potential anti-metastasis agent in the treatment of breast cancer.

In vitro and in vivo anti-tumor activity of Antrodia salmonea against twist-overexpressing HNSCC cells: Induction of ROS-mediated autophagic and apoptotic cell death

Head and neck squamous cell carcinoma (HNSCC) is a relatively common malignancy, characterized by lethal morbidity. Herein, we attempted to investigate the autophagy/apoptosis activities of the submerged fermented broths of Antrodia salmonea (AS) in HNSCC Twist-overexpressing (OECM-1 and FaDu-Twist) cells. AS (0-150 μg/mL) effectively reduced cell viability, colony formation, and downregulated Twist expression in OECM-1 and FaDu-Twist cells compared to FaDu cells. AS- induced apoptosis was mainly associated with activation of caspase-3, PARP cleavage, increased expression of VDAC-1 and disproportionation of Bax/Bcl-2. Annexin V/PI staining suggested late apoptosis induction by AS treatment. AS exhibits enhanced autophagy process mediated via LC3-I/II accumulation, increased acidic vesicular organelles (AVOs) formation and p62/SQSTM1 expression feeding into the apoptotic program. However, pre-treatment with autophagy blockers 3-MA and CQ significantly diminished AS-induced cell death. Additionally, suppression of AS-induced ROS release by treatment with antioxidant N-acetylcysteine (NAC) resulted in reduction of apoptotic and autophagic cell death. In vivo studies strengthened the above observations and showed that AS effectively reduced the tumor volume and tumor weight in OECM-1-xenografted nude mice. This study discovered that Antrodia salmonea exhibits a novel anti-cancer mechanism which could be harnessed as a new potent drug for HNSCC treatment.

EMT and Tumor Turning Point Analysis in 3D Spheroid Culture of HNSCC and Mesenchymal Stem Cells

The prognosis, metastasis, and behavior of head and neck squamous cancer cells are influenced by numerous factors concerning the tumor microenvironment, intercellular communication, and epithelial-to-mesenchymal transition (EMT). The aim of this study was to examine the codependent interaction of the mesenchymal stroma with head and neck squamous cell carcinoma (HNSCC) in a 3D spheroid structure. To simulate stroma-rich and -poor 3D tumor microenvironments, cells of the established cell SCC-040 were cultured with human mesenchymal stromal cells (MSCs), forming 3D stroma-tumor spheroids (STSs). STSs were compared to uniform spheroids of SCC-040 and MSC, respectively. The expressions of CD24, β-catenin, SNAI2, and ZEB2 were analyzed via RT-qPCR. The immunohistochemical expressions of E-cadherin, connexin 43, vimentin, and emmprin were analyzed, and protein expression pathways as well as Akt signaling were assessed via protein analysis. A promotive effect on the expressions of EMT markers ZEB2 (p = 0.0099), SNAI2 (p = 0.0352), and β-catenin (p = 0.0031) was demonstrated in STSs, as was the expression of Akt pathway proteins mTOR (p = 0.007), Erk1/2 (p = 0.0045), and p70 S6 Kinase (p = 0.0016). Our study demonstrated a change in genetic expression patterns early on in tumor development, indicating a tumor turning point.

Zinc Finger Proteins in Head and Neck Squamous Cell Carcinomas: ZNF540 May Serve as a Biomarker

Head and neck squamous cell carcinoma (HNSCC) is one of the ten most common cancers. Most cancer cases originate from alcohol and tobacco consumption. However, studies have demonstrated that human papillomavirus (HPV) infection, particularly HPV-16, may also significantly influence disease progression. The KRAB-ZNF family of genes is involved in epigenetic suppression, and its involvement in carcinogenesis is the subject of extensive studies. The available literature data demonstrate that they may play different roles, both as tumor suppressors and oncogenes. In this study, six ZNF genes, ZFP28, ZNF132, ZNF418, ZNF426, ZNF540, and ZNF880, were tested using several in silico approaches based on the TCGA and GEO datasets. Our analyses indicate that the expression of the analyzed ZNFs was significantly downregulated in tumor tissues and depended on tumor localization. The expression levels of ZNFs differed between HPV-positive vs. HPV-negative patients depending on the clinical-pathological parameters. More specifically, the patients with higher levels of ZNF418 and ZNF540 showed better survival rates than those with a lower expression. In addition, the level of ZNF540 expression in HPV-positive (HPV(+)) patients was higher than in HPV-negative (HPV(-)) patients (p < 0.0001) and was associated with better overall survival (OS). In conclusion, we demonstrate that ZNF540 expression highly correlates with HPV infection, which renders ZNF540 a potential biomarker for HNSCC prognosis and treatment.

Characterizing the epithelial-mesenchymal transition status of circulating tumor cells in head and neck squamous cell carcinoma

BACKGROUND

Circulating tumor cells (CTCs), in particular those undergoing an epithelial-mesenchymal transition (EMT), are a promising source of biomarkers in head and neck squamous cell carcinoma (HNSCC). Our aim was to validate a protocol using microfluidic enrichment (Parsortix platform) with flow-cytometry CTC characterization.

METHOD

Blood samples from 20 treatment naïve HNSCC patients underwent Parsortix enrichment and flow cytometry analysis to quantify CTCs and identify epithelial or EMT subgroups-correlated to clinical outcomes and EMT gene-expression in tumor tissue.

RESULTS

CTCs were detected in 65% of patients (mean count 4 CTCs/ml). CTCs correlated with advanced disease (p = 0.0121), but not T or N classification. Epithelial or EMT CTCs did not correlate with progression-free or overall survival. Tumor mesenchymal gene-expression did not correlate with CTC EMT expression (p = 0.347).

DISCUSSION

Microfluidic enrichment and flow cytometry successfully characterizes EMT CTCs in HNSCC. The lack of association between tumor and CTC EMT profile suggests CTCs may undergo an adaptive EMT in response to stimuli within the circulation.

Tumor-stroma ratio can predict lymph-node metastasis in cT1/2N0 oral tongue squamous cell carcinoma independent of tumor budding grade

BACKGROUND

cT1/2 oral tongue squamous cell carcinoma (OTSCC) often metastasizes to cervical lymph nodes. However, predicting neck lymph-node metastasis (NLM) remains challenging. Pathomorphological evaluation of tumor budding grade (TBG) and tumor-stroma ratio (TSR) reportedly can predict lymph-node metastases. Hence, this study aimed to evaluate TBG and TSR in OTSCC and investigate their relationship to occult NLM and cancer relapse.

METHODS

Clinicopathological data of patients with cT1/2N0 OTSCC treated at the University of Tokyo Hospital between 2007 and 2017 were collected. TBG and TSR were evaluated using hematoxylin-eosin staining and cytokeratin AE1/AE3 immunostaining.

RESULTS

Out of 70 patients, 16 underwent elective neck dissection in addition to primary-tumor resection, whereas 54 did not. During follow-up, NLM was found in 35 patients. NLM correlated with the pathological depth of invasion (pDOI) (p < 0.001), TBG (p = 0.008), and TSR (p < 0.001) in univariate analysis and pDOI (p = 0.01) and TSR (p = 0.02) in multivariate analysis. The 5-year recurrence-free survival rate (RFS) was 78% for patients with a pDOI ≤ 5 mm and stroma-poor tumors and 33% for patients with a pDOI > 5 mm and stroma-rich tumors.

CONCLUSION

Patients with a pDOI > 5 mm and stroma-rich tumors have a high risk for cancer relapse. TSR and pDOI may be promising NLM predictors in cT1/2N0 OTSCC.

Bioinformatic Analysis for Mucoepidermoid and Adenoid Cystic Carcinoma of Therapeutic Targets

Salivary gland neoplasms are a heterogeneous neoplasm group, including mucoepidermoid carcinoma (MECa), adenoid cystic carcinoma (AdCC), and many others. Objective: We aimed to identify new critical genes of MECa and AdCC using bioinformatics analysis. Methods: Gene expression profile of GSE153283 was analyzed by the GEO2R online tool to use the DAVID software for their subsequent enrichment. Protein–protein interactions (PPI) were visualized using String. Cytoscape with MCODE plugin followed by Kaplan–Meier online for overall survival analysis were performed. Results: 97 upregulated genes were identified for MECa and 86 for AdCC. PPI analysis revealed 22 genes for MECa and 63 for AdCC that were validated by Kaplan–Meier that showed FN1 and SPP1 for MECa, and EGF and ERBB2 for AdCC as more significant candidate genes for each neoplasm. Conclusion: With bioinformatics methods, we identify upregulated genes in MECa and AdCC. The resulting candidate genes as possible therapeutic targets were FN1, SPP1, EGF, and ERBB2, and all those genes had been tested as a target in other neoplasm kinds but not salivary gland neoplasm. The bioinformatic evidence is a solid strategy to select them for more extensive research with clinical impact.

Role of Vimentin and E-cadherin Expression in Premalignant and Malignant Lesions of Oral Cavity

To determine the role of Vimentin and E-cadherin expression in oral premalignant and malignant lesions. 68 histopathologically confirmed cases of premalignant and malignant oral cavity lesions enrolled. Biopsy specimens were taken from lesion of all cases and subjected to immunohistochemical evaluation of expression of E-cadherin and Vimentin. We examined the relationships between the expression of these markers and specific clinicopathological features were analyzed. Out of 68 cases 28 showed high vimentin expression (3 + and 4 + grade) and 40 showed low vimentin expression (1 + and 2 + grade). 20 cases out of 68 presented with high E-cadherin expression (3 + and 4 +) and rest 48 with low expression (1 + and 2 +) of the same. Smoking and tobacco chewing reflected non-significant association with their expression. In this study all 28 patients (100%) with high vimentin expression had malignant lesions and 17 (60.7%) presented with metastatic lymph nodes Out of 20 patients with high E-cadherin expression 8(40.0%) had malignant lesions and 12 (60.0%) had pre malignant lesions and 4 (20%) showed nodal metastasis. As tumor stage (TNM) progresses, it showed increased vimentin and decreased E-cadherin expression and vice versa. We concluded that increased vimentin and decreased E-cadherin expression in oral cancers are associated with metastasis and disease progression in terms of upstaging of disease. We can use cellular expression of vimentin and E-cadherin for early diagnosis of disease.

Comparison of plasma- and saliva-derived exosomal miRNA profiles reveals diagnostic potential in head and neck cancer

Background: Head and neck squamous cell carcinomas (HNSCC) lack tumor-specific biomarkers. Exosomes from HNSCC patients carry immunomodulatory molecules, and correlate with clinical parameters. We compared miRNA profiles of plasma- and saliva-derived exosomes to reveal liquid biomarker candidates for HNSCC.

Methods: Exosomes were isolated by differential ultracentrifugation from corresponding plasma and saliva samples from 11 HNSCC patients and five healthy donors (HD). Exosomal miRNA profiles, as determined by nCounter^® SPRINT technology, were analyzed regarding their diagnostic and prognostic potential, correlated to clinical data and integrated into network analysis.

Results: 119 miRNAs overlapped between plasma- and saliva-derived exosomes of HNSCC patients, from which 29 tumor-exclusive miRNAs, associated with TP53, TGFB1, PRDM1, FOX O 1 and CDH1 signaling, were selected. By intra-correlation of tumor-exclusive miRNAs from plasma and saliva, top 10 miRNA candidates with the strongest correlation emerged as diagnostic panels to discriminate cancer and healthy as well as potentially prognostic panels for disease-free survival (DFS). Further, exosomal miRNAs were differentially represented in human papillomavirus (HPV) positive and negative as well as low and high stage disease.

Conclusion: A plasma- and a saliva-derived panel of tumor-exclusive exosomal miRNAs hold great potential as liquid biopsy for discrimination between cancer and healthy as well as HPV status and disease stage. Exosomal miRNAs from both biofluids represent a promising tool for future biomarker studies, emphasizing the possibility to substitute plasma by less-invasive saliva collection.

Hesperetin as an anti-SARS-CoV-2 agent can inhibit COVID-19-associated cancer progression by suppressing intracellular signaling pathways

Hesperetin, an aglycone metabolite of hesperidin with high bioavailability, recently gained attention due to its anti-COVID-19 and anti-cancer properties. Multiple studies revealed that cancer patients are prone to experience a severe form of COVID-19 and higher mortality risk. In addition, studies suggested that COVID-19 can potentially lead to cancer progression through multiple mechanisms. This study proposes that hesperetin not only can be used as an anti-COVID-19 agent but also can reduce the risk of multiple cancer progression by suppressing several intracellular signaling pathways in cancer patients with COVID-19. Therefore, in this review, we attempted to provide evidence demonstrating anti-COVID-19/cancer properties of hesperetin with several mechanisms.

Opposing Roles of Wild-type and Mutant p53 in the Process of Epithelial to Mesenchymal Transition

The central role of an aberrantly activated EMT program in defining the critical features of aggressive carcinomas is well documented and includes cell plasticity, metastatic dissemination, drug resistance, and cancer stem cell-like phenotypes. The p53 tumor suppressor is critical for leashing off all the features mentioned above. On the molecular level, the suppression of these effects is exerted by p53 via regulation of its target genes, whose products are involved in cell cycle, apoptosis, autophagy, DNA repair, and interactions with immune cells. Importantly, a set of specific mutations in the TP53 gene (named Gain-of-Function mutations) converts this tumor suppressor into an oncogene. In this review, we attempted to contrast different regulatory roles of wild-type and mutant p53 in the multi-faceted process of EMT.

Receptor, Signal, Nucleus, Action: Signals That Pass through Akt on the Road to Head and Neck Cancer Cell Migration

Simple Summary

The ecosystem that surrounds a tumour, the microenvironment, has a huge impact on the spread of cancer, but its exact role in the molecular mechanism of spreading is still under scrutiny. This literature review aims to focus on the evidence published on the production of growth factors or proteins from the tumour microenvironment, which initiate signals in cancer cells. This review provides evidence that when Akt, a signalling protein, is activated by different growth factors such as epidermal growth factor, transforming growth factor α/β, vascular endothelial growth factor and nerve growth factor, head and neck cancer cell spreading is stimulated. In a nutshell, it demonstrates that the tumour microenvironment plays an important role in cancer spreading by synthesising and secreting growth factors and suggests that targeting growth-factor-activated Akt in combination therapy could be a valuable therapeutic approach in treating head and neck cancer patients.

Abstract

This review aims to provide evidence for the role of the tumour microenvironment in cancer progression, including invasion and metastasis. The tumour microenvironment is complex and consists of tumour cells and stromal-derived cells, in addition to a modified extracellular matrix. The cellular components synthesise growth factors such as EGF, TGFα and β, VEGF, and NGF, which have been shown to initiate paracrine signalling in head and neck cancer cells by binding to cell surface receptors. One example is the phosphorylation, and hence activation, of the signalling protein Akt, which can ultimately induce oral cancer cell migration in vitro. Blocking of Akt activation by an inhibitor, MK2206, leads to a significant decrease, in vitro, of cancer-derived cell migration, visualised in both wound healing and scatter assays. Signalling pathways have therefore been popular targets for the design of chemotherapeutic agents, but drug resistance has been observed and is related to direct tumour–tumour cell communication, the tumour–extracellular matrix interface, and tumour–stromal cell interactions. Translation of this knowledge to patient care is reliant upon a comprehensive understanding of the complex relationships present in the tumour microenvironment and could ultimately lead to the design of efficacious treatment regimens such as targeted therapy or novel therapeutic combinations.

Clinicopathological and Prognostic Significance of Stromal Patterns in Oral Squamous Cell Carcinoma

Background

Stromal patterns (SP), especially desmoplastic reactions, have recently gained attention as indicators of malignant potential in cancer. In this study, we explored the clinicopathological and prognostic significance of the SP in oral squamous cell carcinoma (OSCC).

Materials and Methods

We reviewed 232 cases of surgically resected OSCC that were not treated with neoadjuvant chemoradiotherapy. We categorized the SP of the OSCC into four groups: immune/inflammatory (84 cases), mature (14 cases), intermediate (78 cases), or immature (56 cases).

Results

The SP category was significantly associated with various clinicopathological factors, such as the histological grade, lymphovascular invasion, neural invasion, and a diffuse invasion pattern. For each of the factors, the immune/inflammatory type was associated with favorable categories, while the immature type was associated with unfavorable categories (p ≤ 0.001). The SP category was also shown to be a prognostic predictor: the 5-year relapse-free survival (RFS) rate was 72.0% for the immune/inflammatory type, 66.7% for the intermediate/mature type, and 31.2% for the immature type (p < 0.0001), and the 5-year overall survival (OS) rate was 85.1% for the immune/inflammatory type, 76.4% for the intermediate/mature type, and 50.0% for the immature type (p < 0.0001). In multivariate analyses, the SP category was identified as an independent prognostic factor for RFS and OS.

Conclusion

Our SP categorization method provides valuable prognostic information in OSCC.

The Role of Zinc Finger Proteins in Various Oral Conditions

The zinc finger proteins (ZNFs) are essential transcription factors, and the genes encoding them constitute about 3% of the entire human genome. They are involved in the development of several tissues, and any alterations in their structure may promote chronic conditions like diabetes and tumorigenesis. Lately, their role in the development, progression, and metastasis of Oral Squamous Cell Carcinoma (OSCC), Epithelial Dysplasia, Oral Lichen Planus, and Periodontitis has been found. The present review aims to describe their role in various oral conditions. Electronic databases like Medline (PubMed) and Scopus were searched for original studies related to the role of ZNFs in various oral conditions. It yielded 48 studies included in the review. It was found that the ZNFs influenced chronic conditions like Oral Cancer and Periodontitis. They act both as tumor suppressors and oncogenes and have an anti-inflammatory effect. The knowledge from the present review may be utilized in designing drugs that prevent unusual expression of specific ZNFs. Besides, they may be applied as prognostic markers due to their high expression specificity in some tumors.

The Combination of Zerumbone with 5-Fluorouracil for Sensitizing Colorectal Cancer-Associated Fibroblasts to Treatment

The present study aimed to evaluate the synergic effects of combination therapy on 5-fluorouracil (5-FU) resistance-cancer-associated fibroblasts (CAFs) to treatment. Chemotherapy resistance is an important challenge in colorectal cancer (CRC) eradication attention to the tumor microenvironment (TME) is very important. CAFs in the TME play an essential role in cancer chemoresistance and relapse. Additionally, many patients with advanced CRC show resistance to 5-FU therapy. Anti-tumorigenic activities of ZER, a chemopreventive compound derived from the rhizomes of the wild ginger, have been demonstrated. Synergistic and potentiating effects of combination therapy, using herbal and chemical drugs, can improve patients’ response. At the first, CAFs were isolated from a CRC patient and sorted by fluorescent-activated cell sorting (FACS), then, confirmed by flow cytometry, and immunocytochemistry (ICC). The effect of 5-FU and ZER on the cell viability was investigated by MTT assay in a dose and time-dependent manner, after that, the expression of vimentin, β-catenin, and survivin was quantified. Apoptosis, cell cycle, and invasion were analyzed by flow cytometry and scratch test, respectively. ZER could significantly sensitize CAFs cells to 5-FU. A combination of 5-FU + ZER revealed a marked decrease in the marker of interest in both mRNA and protein levels compared to control groups, including 5-FU, ZER treated, and untreated cells. Functional evaluation of cells in different groups presented significant suppression in migration of CAFs and an apparent increase in cell arrest and apoptosis by 5-FU + ZER treatment.

STAT3 pathway in cancers: Past, present, and future

Signal transducer and activator of transcription 3 (STAT3), a member of the STAT family, discovered in the cytoplasm of almost all types of mammalian cells, plays a significant role in biological functions. The duration of STAT3 activation in normal tissues is a transient event and is strictly regulated. However, in cancer tissues, STAT3 is activated in an aberrant manner and is induced by certain cytokines. The continuous activation of STAT3 regulates the expression of downstream proteins associated with the formation, progression, and metastasis of cancers. Thus, elucidating the mechanisms of STAT3 regulation and designing inhibitors targeting the STAT3 pathway are considered promising strategies for cancer treatment. This review aims to introduce the history, research advances, and prospects concerning the STAT3 pathway in cancer. We review the mechanisms of STAT3 pathway regulation and the consequent cancer hallmarks associated with tumor biology that are induced by the STAT3 pathway. Moreover, we summarize the emerging development of inhibitors that target the STAT3 pathway and novel drug delivery systems for delivering these inhibitors. The barriers against targeting the STAT3 pathway, the focus of future research on promising targets in the STAT3 pathway, and our perspective on the overall utility of STAT3 pathway inhibitors in cancer treatment are also discussed.

Associations Between ADC and Tumor Infiltrating Lymphocytes, Tumor-Stroma Ratio and Vimentin Expression in Head and Neck Squamous Cell Cancer

RATIONALE AND OBJECTIVES

The present study used diffusion-weighted imaging (DWI) to elucidate possible associations with tumor-infiltrating lymphocytes (TIL), tumor-stroma ratio and vimentin expression in head and neck squamous cell cancer (HNSCC).

MATERIALS AND METHODS

30 patients with primary HNSCC of different localizations were involved in the study. DWI was obtained on a 3 T scanner. Apparent diffusion coefficients (ADC) images were analyzed with a whole lesion measurement using a histogram approach. TIL- and vimentin-expression was calculated on biopsy samples before any form of treatment.

RESULTS

Tumor-stroma ratio correlated with ADC kurtosis (r = 0.46, p = 0.01) and ADC skewness (r = 0.42, p = 0.02). Several ADC parameters were significantly different between stroma rich und tumor rich tumors. ADC entropy correlated significantly with the expression of TIL within the tumor compartment (r = 0.44, p = 0.01). No associations were identified between ADC parameters and vimentin expression.

CONCLUSION

ADC skewness and kurtosis histogram parameters can reflect tumor compartments in HNSCC. ADC entropy was associated with TIL of the tumor compartment but not with those of the stroma compartment, which emphasizes the ability of ADC histogram parameters to reflect distinctive differences of tumors.

Foxhead box D1 promotes the partial epithelial-to-mesenchymal transition of laryngeal squamous cell carcinoma cells via transcriptionally activating the expression of zinc finger protein 532

The presence of cervical lymph node metastases has been considered as the most important adverse prognostic factor for patients with laryngeal squamous cell carcinoma (LSCC). However, the underlying mechanisms remain to be fully revealed. In this study, we explored the expression profile of Foxhead box D1 (FOXD1), its association with epithelial-to-mesenchymal transition (EMT), and its downstream targets in LSCC. Bioinformatic analysis was performed based on the LSCC subset of The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma (TCGA-HSNC) and Chromatin immunoprecipitation (ChIP)-seq data from Cistrome Data Browser. LSCC cell lines AMC-HN-8 and TU212 were used for in vitro studies. Results showed that FOXD1 upregulation was associated with poor prognosis of LSCC. FOXD1 knockdown reduced N-cadherin and Vimentin expression but increased E-cadherin expression in AMC-HN-8 cells. Its overexpression showed opposite effects in TU212 cells. FOXD1 could bind to the promoter of ZNF532 and activate its transcription. ZNF532 overexpression enhanced the invasion of both AMC-HN-8 and TU212 cells. In comparison, its knockdown significantly impaired their invasion. ZNF532 knockdown nearly abrogated the alterations of EMT markers caused by FOXD1 overexpression. Its overexpression largely rescued the phenotypes caused by FOXD1 knockdown. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that ZNF532 correlated genes are largely enriched in extracellular matrix regulations. LSCC patients with high ZNF532 expression (top 50%) had a significantly worse progression-free survival. In summary, this study confirmed that FOXD1 promotes partial-EMT of LSCC cells via transcriptionally activating the expression of ZNF532.

Epithelial-mesenchymal transition related to bone invasion in oral squamous cell carcinoma

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Presence of epithelial-mesenchymal transition markers in tumor-bone interface.

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Dominant infiltrative pattern in bone tissue is associated with lower survival.

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E-cadherin-positive cases were associated with tobacco smoking.

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Vimentin-positive cases were associated with tumors under 4 cm.

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Twist could be strongly involved in bone invasion and in disease progression.

Introduction

Bone invasion is an important prognostic factor in oral squamous cell carcinoma, leading to a lower survival rate and the use of aggressive treatment approaches. Epithelial-mesenchymal transition (EMT) is possibly involved in this process, because it is often related to mechanisms of cell motility and invasiveness. This study examined whether a panel of epithelial-mesenchymal markers are present in cases of oral squamous cell carcinoma with bone invasion and whether these proteins have any relationship with patients’ clinical-pathological parameters and prognostic factors.

Methods

Immunohistochemical analysis of E-cadherin, twist, vimentin, TGFβ1, and periostin was performed in paraffin-embedded samples of 62 oral squamous cell carcinoma cases.

Results

The analysis revealed that most cases (66%) presented with a dominant tumor infiltrative pattern in bone tissue, associated with lower survival rates, when compared with cases with a dominant erosive invasion pattern (P = 0.048). Twenty-seven cases (43%) expressed markers that were compatible with total or partial EMT at the tumor-bone interface. There was no association between evidence of total or partial EMT and other demographic or prognostic features. E-cadherin-positive cases were associated with tobacco smoking (P = 0.022); vimentin-positive cases correlated with tumors under 4 cm (P = 0.043). Twistexpression was observed in tumors with a dominant infiltrative pattern (P = 0.041) and was associated with the absence of periostin (P = 0.031).

Conclusion

We observed evidence of total or partial EMT in oral squamous cell carcinoma bone invasion. The transcription factor twist appears to be involved in bone invasion and disease progression.

San-Zhong-Kui-Jian-Tang Exerts Antitumor Effects Associated With Decreased Cell Proliferation and Metastasis by Targeting ERK and the Epithelial-Mesenchymal Transition Pathway in Oral Cavity Squamous Cell Carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is an aggressive cancer whose 5-year survival rate remains poor. San-Zhong-Kui-Jian-Tang (SZKJT), a Chinese herbal formula, has long been used in clinical practice as adjuvant therapy in cancers. However, its therapeutic effects and molecular mechanisms in OSCC remain unclear.

METHODS

We investigated the potential therapeutic effects and molecular mechanism of SZKJT in OSCC in tumor cell lines and in tumor xenograft mice and evaluated combined SZKJT and cisplatin treatment efficacy. In vitro-cultured OSCC cells were administered SZKJT at different doses or SZKJT plus cisplatin, and cell proliferation, colony formation assays, and cell cycle analysis were used to assess the effects on cancer cell proliferation and apoptosis. We also analyzed the effects of SZKJT on oral cancer cell line migration, the regulation of mitogen-activated protein kinase (MAPK) signaling, and epithelial-mesenchymal transition (EMT)-associated genes. The antitumor effects of SZKJT plus cisplatin were also tested in vivo using a tumor-bearing NOD/SCID mice model.

RESULTS

The results showed that SZKJT effectively inhibited OSCC cell proliferation, induced cell cycle S phase arrest, and induced cell apoptosis. SZKJT also inhibited cell migration by modulating the MAPK signaling and epithelial-mesenchymal transition (EMT) pathway. Further exploration suggested that SZKJT affects OSCC by modulating ERK pathway; downregulating vimentin, fibronectin, and Oct-4; and upregulating E-cadherin. In vivo, SZKJT significantly inhibited tumor growth, and SZKJT and cisplatin exerted synergistic antitumor effects in model animals.

CONCLUSIONS

SZKJT exerts antitumor effects in OSCC cells. Additionally, SZKJT and cisplatin exhibit synergy in OSCC treatment. These findings support the clinical usage of Chinese herbal formulas as adjuvant therapy with chemotherapy in cancer treatment.

Catulin Based Reporter System to Track and Characterize the Population of Invasive Cancer Cells in the Head and Neck Squamous Cell Carcinoma

Head and neck squamous cell carcinoma (HNSCC) is an aggressive tumor with a poor prognosis due to late diagnosis and loco-regional metastasis. Partial or more complete epithelial-mesenchymal transition (EMT) plays a role in tumor progression; however, it remains a challenge to observe the EMT in vivo, due to its transient nature. Here, we developed a novel catulin promoter-based reporter system that allows us to isolate and characterize in vivo a small fraction of invasive cancer cells. The analyses of tumors revealed that Catulin-green fluorescent protein (GFP)-positive cells were enriched in clusters of cells at the tumor invasion front. A functional genomic study unveiled genes involved in cellular movement and invasion providing a molecular profile of HNSCC invasive cells. This profile overlapped partially with the expression of signature genes related to the partial EMT available from the single cell analysis of human HNSCC specimens, highlighting the relevance of our data to the clinical disease progression state. Interestingly, we also observed upregulations of genes involved in axonal guidance-L1 cell adhesion molecule (L1CAM), neuropilin-1, semaphorins, and ephrins, indicating potential interactions of cancer cells and neuronal components of the stroma. Taken together, our data indicated that the catulin reporter system marked a population of invasive HNSCC cells with a molecular profile associated with cancer invasion.

Expression and localisation of methylthioadenosine phosphorylase (MTAP) in oral squamous cell carcinoma and their significance in epithelial-to-mesenchymal transition

Methylthioadenosine phosphorylase (MTAP) is a rate-limiting enzyme in the methionine salvage pathway, which recycles one carbon unit that is lost during polyamine synthesis back into the methionine cycle. Although MTAP deficiency has been reported in various tumours, MTAP is overexpressed and might promote oncogenesis in other cancers, including prostate and colon cancer. Currently, little is known about the MTAP status of oral squamous cell carcinoma (OSCC). In this study, we immunohistochemically examined the expression of MTAP in surgically resected oral epithelial dysplasia (OED, n=7), carcinoma in situ (CIS) (n=16), and OSCC (n=118). In the normal epithelium, MTAP was only weakly expressed in the cytoplasm of the basal layer cells. In OED, CIS, and OSCC, MTAP was uniformly expressed in the cytoplasm of the dysplastic and cancer cells. In addition to cytoplasmic MTAP expression, 45 of 118 cases (38.1%) exhibited increased nuclear expression of MTAP in the cancer cells at the invasive front. Statistical analysis showed that the concomitant nuclear and cytoplasmic expression of MTAP was associated with a high budding score (p=0.0023); poor differentiation (p=0.0044); aggressive invasion patterns (p=0.0001); and features of epithelial-to-mesenchymal transition (EMT), such as loss of E-cadherin expression (p=0.0003) and upregulated expression of vimentin (p=0.0002), slug (p=0.0002), and laminin 5 (p<0.0001). High expression of protein arginine methyltransferase 1 or 5, the functions of which are reported to be inhibited in MTAP-deficient cancer, was associated with the concomitant nuclear and cytoplasmic expression of MTAP (p<0.0001). Concomitant nuclear and cytoplasmic expression of MTAP was marginally significantly associated with worse 5-year relapse-free survival (p=0.045). These findings suggest that MTAP not only plays a role in the oncogenesis of OSCC, but that it might also make it more aggressive by inducing EMT through its activity in the methionine salvage pathway.

Pseudopodium enriched atypical kinase 1(PEAK1) promotes invasion and of melanoma cells by activating JAK/STAT3 signals

Pseudopodium enriched atypical kinase 1(PEAK1) is a non-receptor tyrosine kinase, which is enriched in the pseudopodia of migrating cells and plays an important role in regulating cell migration and proliferation. In the study, we investigate the therapeutic effect of PEAK1 on melanoma cells in vitro and in vivo. We used a lentiviral vector to express short hairpin RNAs (Lv-PEAK1 shRNA) for inhibiting PEAK1 expression in the melanoma SKMEL28 cells. A full-length PEAK1 gene was cloned into the pcDNA 3.1 (+) plasmid and used to infect the melanoma SKMEL19 cells. P6 (also known as Pyridines 6, EMD Chemicals), the Pan-JAK inhibitor, was used to inhibit the Janus kinase/signal transducer and activator of transcription 3 (JAK/STAT3) pathway. The cell counting kit-8 (CCK-8), colony formation assay and transwell assay were used to detect cell proliferation, growth and invasion in vitro. The effect of PEAK1 on melanoma progression in vivo was also evaluated. Protein expression of PEAK1, E-cadherin, vimentin and JAK/STAT3 was measured using western blot assay or immunohistochemistry. The results showed that enforced PEAK1 expression facilitated melanoma cell growth, invasion and metastasis via activating JAK/STAT3 signals, and PEAK1 knockdown inhibited melanoma cell growth, invasion and metastasis via inactivating JAK/STAT3 signals. Further work demonstrated that P6 (500 nM) treatment reversed PEAK1-induced effect in melanoma cells. PEAK1 promotes tumorigenesis and metastasis via activating JAK/STAT3 signals, and PEAK1 knockdown reduced tumorigenesis and metastasis in melanoma via inactivating JAK/STAT3 signals, providing a novel therapeutic strategy for melanoma treatment.

An Epithelial-Mesenchymal Transition Hallmark Gene-Based Risk Score System in Head and Neck Squamous-Cell Carcinoma

Background

Epithelial-to-mesenchymal transition (EMT) program plays a critical role in cancer. Thus, we attempted to generate a risk score system according to the expression pattern of different EMT hallmark genes in head and neck squamous-cell carcinoma (HNSC).

Methods

Differentially expressed EMT hallmark genes were screened to generate a risk score (RS) on TCGA HNSC dataset. The relative prognostic value of the RS compared to clinicopathological characteristics was explored using multivariable Cox analysis. Functional enrichment analysis was performed to reveal the biological characteristics. An external dataset was applied to validate the prognostic value of the RS.

Results

Nine genes constituted the EMT hallmark gene-based RS, which is significantly associated with poor prognosis and could successfully divide patients with HNSC into high- and low-risk groups. The RS was also an independent prognostic indicator compared to routine clinical factors.

Conclusion

We proposed and validated a nine-EMT hallmark gene-based risk score system in HNSC.

Epithelial-to-Mesenchymal Transition and Neoangiogenesis in Laryngeal Squamous Cell Carcinoma

Simple summary

The mechanism of epithelial–mesenchymal transition is fundamental for carcinogenesis, tumor progression, cancer cell invasion, metastasis, recurrence, and therapy resistance, resulting in cellular junction degradation and increased cellular motility. The same factors that drive epithelial cells toward a mesenchymal phenotype may also drive endothelial cells toward a proangiogenic phenotype. This study aimed to investigate a potential interplay between epithelial–mesenchymal transition and angiogenesis in laryngeal carcinoma. In our study, univariate Cox regression identified pN+ status and Slug expression as predictive of disease-free survival, while a trend toward significance emerged for CD105-assessed microvessel density and N-cadherin expression. In the multivariate Cox regression model, pN-status, Slug, and N-cadherin expressions retained their significant values in predicting disease-free survival. Data from our study support the hypothesis of a mutual concurrence of epithelial–mesenchymal transition and angiogenesis in the development of an aggressive phenotype in laryngeal squamous cell carcinoma.

Abstract

The mechanism of epithelial–mesenchymal transition (EMT) is fundamental for carcinogenesis, tumor progression, cancer cell invasion, metastasis, recurrence, and therapy resistance, comprising important events, such as cellular junction degradation, downregulation of epithelial phenotype markers, overexpression of mesenchymal markers, and increase in cellular motility. The same factors that drive epithelial cells toward a mesenchymal phenotype may also drive endothelial cells toward a proangiogenic phenotype. The aim of this exploratory study was to investigate a potential interplay between EMT and angiogenesis (quantified through CD105 expression) in laryngeal carcinoma (LSCC). CD105-assessed microvessel density (MVD) and EMT markers (E-cadherin, N-cadherin, Snail, Slug, Zeb1, and Zeb2) were assessed on 37 consecutive LSCC cases. The univariate Cox regression model identified pN+ status (p = 0.0343) and Slug expression (p = 0.0268) as predictive of disease-free survival (DFS). A trend toward significance emerged for CD105-assessed MVD (p = 0.0869) and N-cadherin expression (p = 0.0911). In the multivariate Cox model, pN-status, Slug, and N-cadherin expressions retained their significant values in predicting DFS (p = 0.0346, p = 0.0430, and p = 0.0214, respectively). Our data support the hypothesis of a mutual concurrence of EMT and angiogenesis in driving LSCC cells toward an aggressive phenotype. To better characterize the predictive performance of prognostic models based on EMT and angiogenesis, further large-scale prospective studies are required.

Head and neck cancer: Current challenges and future perspectives

Head and neck cancers are a heterogeneous, aggressive and genetically complex collection of malignancies of the oral cavity, nasopharynx, oropharynx, hypopharynx, larynx, paranasal sinuses and salivary glands, which are difficult to treat. About 90% of all head and neck cancers are squamous cell carcinomas (HNSCC). Larynx and Oral cavity carcinomas are generally related with tobacco consumption, alcohol abuse (or both), but pharynx carcinomas are generally associated with infection of human papillomavirus (HPV), especially HPV-16 subtype. Thus, usually HNSCC can be separated into HPV-negative and HPV-positive categories. Despite substantial efforts invested into therapeutic development of HNSCC, the 5-year survival rate of patients with HNSCC still remains dismal. The primary reason being late diagnosis, recurrent metastasis, relapse and resistance to therapies. Currently surgery and radiotherapy represent the baseline treatment options for most initial stage HNSCC patients, but these treatments are associated with significant morbidity and poor prognosis. Moreover, the issue of resistance to both radiotherapy/chemotherapy and recurrent relapse are common in HNSCC. Elucidation of the genetic landscape, tumor microenvironment and aberrant signaling pathways have generated new insights into the molecular pathogenesis of this disease. Thus, the scientific research has therefore been focused on the understanding of HNSCC biology and immunobiology to identification of predictive/prognostic biomarkers, which will be key to develop more effective targeted therapies with less toxicity and high specificity.

Genes involved in the epithelial-mesenchymal transition in oral cancer: A systematic review

OBJECTIVE

Epithelial-mesenchymal transition (EMT) is considered the initial step in the invasion-metastasis cascade. The aim of this systematic review was to study the signature of genes involved in the EMT process in oral cancer (OC) confirmed by protein expression and its possible relationship with oral squamous cell carcinoma (OSCC) prognostic variables.

MATERIALS AND METHODS

A search of the scientific literature was carried out with no start date restriction until 17 September 2020 in the electronic databases Pubmed/MEDLINE, Web of Science, Cochrane Library and Scopus, following specific eligibility criteria. The methodological quality of the included studies was assessed using the Newcastle-Ottawa tool.

RESULTS

A total of 8 retrospective cohort studies were included, all of them performed in China and with low risk of bias. Overexpression of the genes HNRNPC, ITGA5, HMGA2 and SRSF3, and low expression of ALDH3A1 and ARID2 promote EMT in OC. The more advanced clinical stages of the TNM classification were significantly associated with overexpression of HNRNPC, ITGA5, HMGA2 and SRSF3, and low expression of ARID2.

CONCLUSIONS

HNRNPC, ITGA5, HMGA2, SRSF3, ALDH3A1 and ARID2 genes were associated with EMT process. Over- or under-expression of these genes is associated with worse stages of OSCC and/or worse prognosis of the tumor. Further studies on this topic are needed in different countries to be able to confirm these results, since the detection of these genes can help to know which tumors have a worse prognosis.

Clinicopathological significance of SOX4 and epithelial-mesenchymal transition markers in patients with laryngeal squamous cell carcinoma

OBJECTIVE

Sex-determining region-Y-related high-mobility-group box 4 (SOX4) is associated with the metastasis and prognosis of many cancer types. However, studies on the role of SOX4 in laryngeal squamous cell carcinoma (LSCC) are few, and hence the mechanism is unclear. Epithelial-mesenchymal transition (EMT) allows neoplastic cells to gain the plasticity and motility required for tumor progression and metastasis. This study aimed to analyze the relationship between SOX4 and EMT, and their relationship with clinicopathological factors and related prognosis.

METHODS

Immunohistochemical staining was used to detect the positive expression of SOX4 protein, EMT-related transcription factor protein, and related marker protein in 127 LSCC tissue samples. At the same time, data on various parameters of clinical pathology and postoperative survival were collected.

RESULTS

The positive expression rate of SOX4 and Slug in LSCC was related to pathological differentiation, Lymph node metastasis (LNM), and pathological TNM of a tumor. The expression rates of ZEB1, E-cadherin, N-cadherin, and β-catenin in LSCC correlated with LNM and pTNM. The expression of SOX4, combined expression of SOX4 and ZEB1, and LNM were independent prognostic factors for the total survival time of patients with LSCC.

CONCLUSIONS

In summary, SOX4 was vital in the LSCC EMT process, which might be mediated by transcription factor ZEB1. SOX4 and ZEB1 might serve as potential biomarkers of metastasis and prognosis, as well as promising therapeutic targets of LSCC.

Neuropilin-1 predicts poor prognosis and promotes tumor metastasis through epithelial-mesenchymal transition in gastric cancer

We aimed to determine whether Neuropilin-1 (NRP1) promotes gastric cancer (GC) metastasis by inducing epithelial-mesenchymal transition (EMT), and to clarify its regulatory mechanism. Using the data of GC patients in The Cancer Genome Atlas (TCGA) and Gene Tissue Expression (GTEx) databases, combined with the data of GC patients in our medical center, the effect of NRP1 on the prognosis of GC patients were analyzed. Then, we investigated the role of NRP1 in GC metastasis and its potential mechanism. The level of NRP1 was up-regulated in GC tissues and associated with poor prognosis of GC patients. The expression of NRP1 was closely related to maximum tumor diameter, invasion depth, lymphnode metastasis, distant metastasis, and advanced TNM stage, and was an independent prognostic factor for overall survival (OS) in GC patients. Besides, the results of in vitro indicated that NRP1 could induce EMT to promote the migration and invasion of GC cells by activating PI3K/Akt signaling pathway, and the HGF/c-Met axis was involved in this process. This study determined that NRP1 was a gene that promotes gastric cancer. NRP1 induced EMT to enhance the migration and invasion ability of GC cells by activating PI3K/Akt signaling pathway. NRP1 was an independent prognostic marker for OS in GC patients and expected to be a therapeutic target for GC patients.

4sc-202 and Ink-128 cooperate to reverse the epithelial to mesenchymal transition in OSCC

Treatment of oral squamous cell carcinoma remains a challenge due to a high incidence of treatment resistance, which is followed by tumor recrudescence and metastasis to the lymph nodes. Thus, it is important to explore novel inhibitors of OSCC. Here, we aimed to identify drugs that may cooperate with histone deacetylase inhibitors to reverse the EMT, inhibit EMT and cell migration and invasion, and contribute to therapeutic efficacy. We found that treatment with 4sc-202 potently reversed the EMT and thereby inhibited cell migration and invasion in vitro, in part by inducing expression of the FoxO1 tumor-suppressor gene. Furthermore, 4sc-202 also synergized with Ink-128 to inhibit tumor migration and invasion in vitro. Mechanistically, 4sc-202 induced FoxO1 expression, whereas Ink-128 promoted nuclear translocation of FoxO1. Our findings indicated that FoxO1 might reverse the EMT by interacting with Twist1 in OSCC. In conclusion, we identified an effective combination therapy involving class I histone deacetylase and mammalian target of rapamycin complex 1/2 inhibition that effectively blocked the EMT of tumor cells by upregulating FoxO1 expression to inhibit Twist1 transcription. These data have implications for developing new targets for early diagnosis and treatment of OSCC.