E-cadherin downregulation and Twist overexpression since early stages of oral carcinogenesis

Fibroblasts Regulate the Transformation Potential of Human Papillomavirus-positive Keratinocytes

Persistent human papillomavirus (HPV) infection is necessary but insufficient for viral oncogenesis. Additional contributing co-factors, such as immune evasion and viral integration have been implicated in HPV-induced cancer progression. It is widely accepted that HPV+ keratinocytes require co-culture with fibroblasts to maintain viral episome expression, yet the exact mechanisms for this have yet to be elucidated. Here we present comprehensive RNA sequencing and proteomic analysis demonstrating that fibroblasts not only support the viral life cycle, but reduce HPV+ keratinocyte transformation. Our co-culture models offer novel insights into HPV-related transformation mechanisms.

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.

Extracellular matrix remodelling and stiffening contributes to tumorigenesis of salivary carcinoma ex pleomorphic adenoma--A study based on patient-derived organoids

BACKGROUND

Salivary carcinoma ex pleomorphic adenoma (CXPA) is defined as a carcinoma that develops from benign pleomorphic adenoma (PA). Abnormally activated Androgen signaling pathway and amplification of HER-2/neu(ERBB-2) gene are known to be involved in CXPA tumorigenesis. Recent progress in tumour microenvironment research has led to identification that extracellular matrix (ECM) remodelling and increased stiffness act as critical contributing role in tumour carcinogenesis. This study examined ECM modifications to elucidate the mechanism underlying CXPA tumorigenesis.

RESULTS

PA and CXPA organoids were successfully established. Histological observation, immunohistochemistry (IHC), and whole-exome sequencing demonstrated that organoids recapitulated phenotypic and molecular characteristics of their parental tumours. RNA-sequencing and bioinformatic analysis of organoids showed that differentially expressed genes are highly enriched in ECM-associated terms, implying that ECM alternations may be involved in carcinogenesis. Microscopical examination for surgical samples revealed that excessive hyalinized tissues were deposited in tumour during CXPA tumorigenesis. Transmission electron microscopy confirmed that these hyalinized tissues were tumour ECM in nature. Subsequently, examination by picrosirius red staining, liquid chromatography with tandem mass spectrometry, and cross-linking analysis indicated that tumour ECM was predominantly composed of type I collagen fibers, with dense collagen alignment and an increased level of collagen cross-linking. IHC revealed the overexpression of COL1A1 protein and collagen-synthesis-related genes, DCN and IGFBP5 (p < 0.05). Higher stiffness of CXPA than PA was demonstrated by atomic force microscopy and elastic imaging analysis. We utilized hydrogels to mimic ECM with varying stiffness degrees in vitro. Compared with softer matrices (5Kpa), CXPA cell line and PA primary cells exhibited more proliferative and invasive phenotypes in stiffer matrices (50Kpa, p < 0.01). Protein-protein interaction (PPI) analysis of RNA-sequencing data revealed that AR and ERBB-2 expression was associated with TWIST1. Moreover, surgical specimens demonstrated a higher TWIST1 expression in CXPA over PA. After knocking down TWIST1 in CXPA cells, cell proliferation, migration, and invasiveness were significantly inhibited (p < 0.01).

CONCLUSION

Developing CXPA organoids provides a useful model for cancer biology research and drug screening. ECM remodelling, attributed to overproduction of collagen, alternation of collagen alignment, and increased cross-linking, leads to increased ECM stiffness. ECM modification is an important contributor in CXPA tumorigenesis.

Unraveling the Role of Epithelial-Mesenchymal Transition in Adenoid Cystic Carcinoma of the Salivary Glands: A Comprehensive Review

Salivary adenoid cystic carcinoma (SACC) is considered a challenging malignancy; it is characterized by a slow-growing nature, yet a high risk of recurrence and distant metastasis, presenting significant hurdles in its treatment and management. At present, there are no approved targeted agents available for the management of SACC and systemic chemotherapy protocols that have demonstrated efficacy remain to be elucidated. Epithelial-mesenchymal transition (EMT) is a complex process that is closely associated with tumor progression and metastasis, enabling epithelial cells to acquire mesenchymal properties, including increased mobility and invasiveness. Several molecular signaling pathways have been implicated in the regulation of EMT in SACC, and understanding these mechanisms is crucial to identifying new therapeutic targets and developing more effective treatment approaches. This manuscript aims to provide a comprehensive overview of the latest research on the role of EMT in SACC, including the molecular pathways and biomarkers involved in EMT regulation. By highlighting the most recent findings, this review offers insights into potential new therapeutic strategies that could improve the management of SACC patients, especially those with recurrent or metastatic disease.

Biomarkers of malignant transformation in oral leukoplakia: from bench to bedside

Oral leukoplakia is a common precursor lesion of oral squamous cell carcinoma, which indicates a high potential of malignancy. The malignant transformation of oral leukoplakia seriously affects patient survival and quality of life; however, it is difficult to identify oral leukoplakia patients who will develop carcinoma because no biomarker exists to predict malignant transformation for effective clinical management. As a major problem in the field of head and neck pathologies, it is imperative to identify biomarkers of malignant transformation in oral leukoplakia. In this review, we discuss the potential biomarkers of malignant transformation reported in the literature and explore the translational probabilities from bench to bedside. Although no single biomarker has yet been applied in the clinical setting, profiling for genomic instability might be a promising adjunct.

Serum Response Factor-Regulated IDO1/Kyn-Ahr Pathway Promotes Tumorigenesis of Oral Squamous Cell Carcinoma

Serum response factor (SRF) regulates pro-carcinogenic genes in various cancers, but its role in oral squamous cell carcinoma (OSCC) remains unclear. SRF expression in 70 OSCC samples was detected via immunohistochemistry. Abundant SRF expressed in OSCC tissues was closely associated with tumor metastasis. SRF-overexpressing OSCC cells were constructed to evaluate how SRF affects OSCC cell tumorigenesis and epithelial-to-mesenchymal transition (EMT) in vitro and in vivo. Overexpressed SRF increased OSCC cell migration and invasion in vitro and tumor growth and invasion in vivo. This promoted EMT, characterized by decreased and increased expression of E- and N-cadherin, respectively. Furthermore, an analysis of RNA sequences of transcriptional targets of SRF showed that SRF transactivated the indoleamine 2, 3-dioxygenase 1 (IDO1)/kynurenine-aryl hydrocarbon receptor (Kyn-AhR) signaling pathway in OSCC cell lines. Direct SRF binding to the IDO1 gene promoter upregulated transcription, which was detected through chromatin immunoprecipitation and dual luciferase reporter assays. Inhibiting IDO1 or AhR impaired SRF-induced migration and invasion and prevented EMT in OSCC cells. Our results demonstrated that SRF is a critical regulator of the IDO1/Kyn-AhR signaling pathway. This in turn increases OSCC cell migration and invasion by modulating EMT, which, consequently, favors OSCC cell growth and metastasis. We revealed a novel molecular mechanism through which SRF modulates OSCC metastasis. This should provide potential targets or biomarkers for OSCC diagnosis and treatment.

SNAIL1 is involved in the control of the epithelial-mesenchymal transition in oral tongue squamous cell carcinoma

OBJECTIVE

The aim of the present study was to investigate the role of SNAIL1, E-cadherin, and N-cadherin immunoexpression in oral tongue carcinogenesis. In addition, we evaluated in vitro the impact of silencing of the nuclear transcription factor SNAIL1 on the viability, apoptosis, proliferation, migration, and invasion of SCC-9 and HSC-3 cells.

STUDY DESIGN

Immunohistochemical analysis of SNAIL1, E-cadherin, and N-cadherin was carried out in 47 samples representing oral epithelial dysplasia (OED) and 41 oral tongue squamous cell carcinoma (OTSCC). The suppression of SNAIL1 expression was performed using shRNA-expression vectors in HSC-3 and SCC-9 cells to investigate in vitro the impact of SNAIL1 on proliferation, apoptosis, viability, migration, and invasion of SCC-9 and HSC-3 cells.

RESULTS

Significant differences were observed in the expression of SNAIL1, E-cadherin, and N-Cadherin between OTSCC and OED. A low membrane expression of E-cadherin was strongly associated with poor overall survival in patients with OTSCC (P < .05), but the association did not withstand the Cox multivariate survival analysis. SNAIL1 silencing played a key role in the suppression of epithelial-mesenchymal transition and inhibited migration and invasion of HSC-3 cells (P < .0001, P < .01, respectively). In SCC-9 cells, SNAIL1 silencing promoted a significant reduction in the proliferation (P < .0001) and invasion (P < .0001).

CONCLUSIONS

The epithelial-mesenchymal transition is present in different stages of oral tongue carcinogenesis, and SNAIL1 plays a key role in this process, although the underlying mechanisms still need to be elucidated. Thus, SNAIL1 might be a promising therapeutic target in OTSCC.

TWIST1 regulates proliferation, migration, and invasion and is a prognostic marker for oral tongue squamous cell carcinoma

BACKGROUND

Epithelial-mesenchymal transition is one of the main mechanisms for tumor progression and metastasis. Transcription factors such as TWIST1 are key regulators of the epithelial-mesenchymal transition and are regarded as potential therapeutic targets for the treatment of cancer. The purpose of this study was to examine TWIST1 as a possible epithelial-mesenchymal transition-related prognostic biomarker in oral epithelial dysplasia and oral tongue squamous cell carcinomas, as well as the biological behavior of TWIST1-silencing in oral tongue squamous cell carcinomas cell lines.

METHODS

Immunohistochemical analysis of TWIST1, E-cadherin, and N-cadherin was carried out in 47 samples representing oral epithelial dysplasia and 41 oral tongue squamous cell carcinomas. The suppression of TWIST1 expression was performed using shRNA-expression vectors in HSC-3 and SCC-9 cells to investigate in vitro the impact of TWIST1 on proliferation, apoptosis, viability, migration, and invasion of SCC-9 and HSC-3 cells.

RESULTS

The expression of nuclear TWIST1 was significantly higher in oral tongue squamous cell carcinomas than in oral epithelial dysplasis (p < 0.0001), whereas TWIST1 in the cytoplasm was more expressed in oral epithelial dysplasis (p = 0.012). The high cytoplasmic expression of TWIST1 was significantly associated with shortened overall survival (p < 0.05), and increased nuclear TWIST1 expression was significantly related to high risk of recurrence (p = 0.03). Knockdown of TWIST1 in oral tongue squamous cell carcinomas cells induced the expression of E-cadherin and inhibited N-cadherin, which were followed by decreased proliferation, migration, and invasion.

CONCLUSIONS

Our research suggests that TWIST1 is linked to the development of oral tongue carcinogenesis and may be used as a prognostic indicator and therapeutic target for oral tongue squamous cell carcinomas patients.

The Crossroads of Periodontitis and Oral Squamous Cell Carcinoma: Immune Implications and Tumor Promoting Capacities

Periodontitis (PD) is increasingly considered to interact with and promote a number of inflammatory diseases, including cancer. In the case of oral squamous cell carcinoma (OSCC) the local inflammatory response associated with PD is capable of triggering altered cellular events that can promote cancer cell invasion and proliferation of existing primary oral carcinomas as well as supporting the seeding of metastatic tumor cells into the gingival tissue giving rise to secondary tumors. Both the immune and stromal components of the periodontium exhibit phenotypic alterations and functional differences during PD that result in a microenvironment that favors cancer progression. The inflammatory milieu in PD is ideal for cancer cell seeding, migration, proliferation and immune escape. Understanding the interactions governing this attenuated anti-tumor immune response is vital to unveil unexplored preventive or therapeutic possibilities. Here we review the many commonalities between the oral-inflammatory microenvironment in PD and oral-inflammatory responses that are associated with OSCC progression, and how these conditions can act to promote and sustain the hallmarks of cancer.

Crosstalk between the oral microbiota, mucosal immunity, and the epithelial barrier regulates oral mucosal disease pathogenesis

Oral mucosal disease (OMD), which is also called soft tissue oral disease, is described as a series of disorders or conditions affecting the mucosa and soft tissue in the oral cavity. Its etiology is unclear, but emerging evidence has implicated the influence of the composition of the oral mucosa and saliva-resident microbiota. In turn, this dysbiosis effects the immune response balance and epithelial barrier function, followed by the occurrence and progression of OMD. In addition, oral microbial dysbiosis is diverse in different types of diseases and different disease progressions, suggesting that key causal pathogens may exist in various oral pathologies. This narrative literature review primarily discusses the most recent findings focusing on how microbial dysbiosis communicates with mucosal adaptive immune cells and the epithelial barrier in the context of five representative OMDs, including oral candidiasis (OC), oral lichen planus (OLP), recurrent aphthous ulcer (RAU), oral leukoplakia (OLK), and oral squamous cell carcinoma (OSCC), to provide new insight into the pathogenetic mechanisms of OMDs.

EZH2 Knockout in Oral Cavity Basal Epithelia Causes More Invasive Squamous Cell Carcinomas

Oral squamous cell carcinoma (oral SCC) is an aggressive disease and despite intensive treatments, 5-year survival rates for patients have remained low in the last 20 years. Enhancer of zeste homolog 2 (EZH2), part of polycomb repressive complex 2 (PRC2), is highly expressed in human oral SCC samples and cell lines and has been associated with greater epithelia-to-mesenchymal transition (EMT), invasion, and metastasis. Here we developed a tamoxifen-regulated, transgenic mouse line (KcEZH2) in which EZH2 is selectively knocked out (KO) in some tongue epithelial basal stem cells (SCs) in adult mice. EZH2 KO SCs do not show the H3K27me3 mark, as assessed by double-label immunofluorescence. We used this mouse line to assess EZH2 actions during oral tumorigenesis with our immunocompetent 4-nitroquinoline 1-oxide (4-NQO) model of oral SCC. We report that higher percentages of mice with invasive SCCs and high-grade neoplastic lesions are observed in mice containing EZH2 KO SCs (KcEZH2-2TΔ and KcEZH2-5TΔ mice). Moreover, EZH2 expression does not correlate with the expression of markers of invasive SCCs. Finally, EZH2 KO cells that are E-cadherin+ are present at invasion fronts infiltrating underlying muscle tissue. Our findings indicate that the knockout of EZH2 in basal SCs of tongue epithelia results in more aggressive carcinomas, and this should be considered when targeting EZH2 as a therapeutic strategy.

Epithelial-to-mesenchymal transition in oral squamous cell carcinoma: Challenges and opportunities

Oral squamous cell carcinoma (OSCC) is the most common malignancy representing 90% of all forms of oral cancer worldwide. Although great efforts have been made in the past decades, the 5-year survival rate of OSCC patients is no more than 60% due to tumor metastasis and subsequent recurrence. The metastasis from the primary site is due to a complex process known as epithelial-to-mesenchymal transition (EMT). During the EMT, epithelial cells gradually acquire the structural and functional characteristics of mesenchymal cells, leading to the upregulation of cell migration and the promotion of tumor cell dissemination. Therefore, EMT attracted broad attention due to its close relationship with cancer invasion and metastasis. Therefore, in the present review, an extensive description of the current research on OSCC and the role of EMT in this cancer type is provided, including diverse EMT markers, regulatory networks and crucial EMT-inducing transcription factors in OSCC. Moreover, a brief summary was made regarding the current application of EMT-correlated indexes in the prognostic analysis of OSCC patients, and the potential therapeutic approaches against OSCC and difficulties in the development of an effective anti-EMT treatment are discussed. Our aim is to provide novel insights to develop new strategies to combat OSCC by targeting EMT.

Biological role of epithelial-mesenchymal-transition-inducing transcription factors in head and neck squamous cell carcinoma: A systematic review

OBJECTIVE

The aim of this systematic review was to explore the biological functions and mechanisms of epithelial-mesenchymal transition-inducing transcription factors in head and neck squamous cell carcinoma-derived cell lines. In addition, we analyzed the possible usefulness of epithelial-mesenchymal transition-inducing transcription factors as a future therapeutic target.

DESIGN

An electronic search was performed in EMBASE, Medline/PubMed, Chinese BioMedical Literature Databases, and Cochrane Collaboration Library. Articles evaluating the relationship between epithelial-mesenchymal transition-inducing transcription factors and the biological behavior of head and neck squamous cell carcinoma cell lines were selected for this systematic review. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

After application of the previously established inclusion/exclusion criteria, 23 articles were included in the qualitative synthesis. Our study showed that epithelial-mesenchymal transition-inducing transcription factors are essential components during the progression of head and neck squamous cell carcinomas and their overexpression is associated with a greater capacity of dissemination and survival of the tumor and resistance to cancer treatment. The inhibition of epithelial-mesenchymal transition-inducing transcription factors is able to reverse the epithelial-mesenchymal transition process and to increase the sensitivity of head and neck squamous cell carcinoma cell lines to radio/chemotherapy.

CONCLUSIONS

Analysis of the expression of epithelial-mesenchymal transition-inducing transcription factors for the prediction of prognosis and response to cancer treatment may have a significant clinical impact.

Prognostic value of the immunohistochemical detection of epithelial-mesenchymal transition biomarkers in oral epithelial dysplasia: A systematic review

BACKGROUND

Oral potentially malignant disorders (OPMDs) comprise a range of clinical-pathological alterations that are frequently characterized as architectural and cytological derangements upon histological analysis. Epithelial-mesenchymal transition (EMT) has been proposed as a critical mechanism for the acquisition of the malignant phenotype in neoplastic epithelial processes. This study aims to systematically review the current findings on the immunohistochemical expression of epithelial-mesenchymal transition markers in oral potentially malignant disorders and to evaluate their possible application as biomarkers associated with the progression of oral epithelial dysplasias.

MATERIAL AND METHODS

A systematic search was performed in the following databases: PubMed, EMBASE, Chinese BioMedical Literature Database, and Cochrane Library. Articles that evaluated the relationship between the expression of EMT markers and the degree of oral epithelial dysplasia were selected for the systematic review. The quality of each eligible study was evaluated by independent reviewers that used operationalized prognostic biomarker reporting guidelines (REMARK).

RESULTS

Seventeen articles met all inclusion criteria and were selected. The EMT markers analyzed exhibited an important association with the prognosis of the cases evaluated. The results showed a progressive increase in the expression of nuclear transcription factors and markers of mesenchymal differentiation, as well as negative regulation of epithelial and cell adhesion markers, according to the stage of oral epithelial dysplasia.

CONCLUSIONS

The dysregulation of expression of important EMT components in oral dysplastic epithelium is a potential prognostic marker in OPMDs.

Expression of E- Cadherin and Levels of Dysplasia in Oral Leukoplakia - A Prospective Cohort Study

AIM

Enormous attempts have been made to develop and establish markers that determines the susceptibility of potentially malignant tissues to transform to oral cancer. E - cadherin encoded by CDH1 gene is a protein which plays an important role in cellular adhesion. This study aimed to assess the relationship between the expression of E- cadherin and different grades of epithelial dysplasia in oral leukoplakia.

MATERIALS AND METHODS

Tumour biopsies from fifty leukoplakia patients was collected. Half of the tissue was sent for histopathological examination and other half was subjected to see E - cadherin expression by real time PCR.

RESULTS

On assessing, the expression of E - cadherin was found to be high in samples with mild dysplasia followed by samples with moderate dysplasia. Samples with severe dysplastic feature showed least expression of E - cadherin. All statistical analyses were performed using Statistical Package for Social science (SPSS) and was proven that there is significant decrease in the expression of E - cadherin as the degree of dysplasia increases with a p value 0.001 and confidence interval 95%.

CONCLUSION

We conclude that loss of E - cadherin can be used as a tumour marker that could determine the susceptibility of normal and potentially malignant tissues to transform into oral cancers. To generalise our results, further prospective studies with a large sample size using quantitative real time PCR to read the gene expression should be carried out at multi centre levels.
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Recent trends in predictive biomarkers for determining malignant potential of oral potentially malignant disorders

Despite of the tremendous advancements in the field of cancer prevention, detection and treatment, the overall prognosis of oral squamous cell carcinoma (OSCC) still remains poor. This can be partly imparted to the lack of early detection of oral potentially malignant disorders (OPMDs), especially those at a higher risk of progression into OSCC. Over years, various specific and non-specific markers have been introduced that could predict the malignant transformation of OPMDs; however detail information on these OPMD markers in a concise manner is lacking. Moreover, their use on daily clinical basis still remains questionable. With continuous research in the field of cytology and genomics, several contemporary biomarkers have been discovered that are not yet foregrounded and proved to be more promising than those used conventionally. Here, in the present paper, we overview several recently concluded predictive biomarkers with special emphasis on their role in molecular pathogenesis of OSCC transformation. These markers can be used for risk assessment of malignant transformation in patients with OPMDs as well as for prophylactic conciliation and fair management of the high-risk OPMD patient group.

Alterations in the expression of EMT-related proteins claudin-1, claudin-4 and claudin-7, E-cadherin, TWIST1 and ZEB1 in oral lichen planus

BACKGROUND

Oral lichen planus (OLP) is a chronic T-cell-mediated inflammatory disease, which is associated with increased risk of developing oral squamous cell carcinoma. Epithelial-to-mesenchymal transition is a physiological phenomenon occurring during growth and organogenesis, but it has also an important role in tumorigenesis. In the present work, we studied the expression of known epithelial-to-mesenchymal transition markers in oral lichen planus.

METHODS

In total, 54 oral lichen planus and 22 control samples were analyzed for epithelial-to-mesenchymal transition markers. Samples were immunohistochemically stained for claudin-1, claudin-4 and claudin-7, cadherin-1 (E-cadherin), Twist-related protein 1 (TWIST1) and zinc finger E-box-binding homeobox 1 (ZEB1).

RESULTS

The expression of claudin-1, claudin-4 and E-cadherin was significantly weaker in oral lichen planus epithelium compared to controls (P < 0.001). The quantity of claudin-7-expressing cells (P < 0.001) and claudin-7 staining intensity (P < 0.05) in the stroma was greater in lichen planus than in control samples. TWIST1 and ZEB1 stainings were negative in the epithelium in both lichen planus and controls. The number of TWIST1-expressing cells in the stroma was higher in lichen planus than in controls (P < 0.001). There was a statistically significant difference in ZEB1 staining intensity in the stroma between lichen planus and control samples (P < 0.05).

CONCLUSIONS

The data indicate that the expression of claudin-1, claudin-4 and E-cadherin is decreased in oral lichen planus. This may lead to disturbance in epithelial tight junctions, cell-cell connections and epithelial permeability, contributing to oral lichen planus pathogenesis. Based on the present study, the role of TWIST1 and ZEB1 in oral lichen planus remains unclear.

Twist and E-cadherin deregulation might predict poor prognosis in lower lip squamous cell carcinoma

OBJECTIVE

The aim of this study was to evaluate the expression of Twist and E-cadherin in lower lip squamous cell carcinoma (LLSCC) and their association with clinicopathologic parameters.

STUDY DESIGN

Fifty-nine cases of LLSCC were analyzed by applying immunohistochemistry techniques in a semiquantitative manner. The systems proposed by Bryne etal., Brandwein-Gensler etal., and Almangush etal. were applied for analysis of the histopathologic malignancy grading system.

RESULTS

Higher E-cadherin expression (general and membrane) was observed in cases presenting with disease-free survival after 5years of follow-up (P < .05). Higher Twist expression was observed in lesions classified as being in advanced stages, displaying recurrence, and having a high degree of malignancy. A significant negative correlation was detected between cytoplasmic Twist expression and membrane E-cadherin expression (P = .028). A statistically significant relationship was detected between high total Twist expression in tumors classified as high risk by Brandwein-Gensler etal., and no significant difference was observed among total, membrane, and cytoplasmic E-cadherin expressions in LLSCC cases and the 3 applied grading systems (P > .05).

CONCLUSIONS

The results of the present study suggest the potential involvement of Twist and E-cadherin in the modulation of events related to worse prognoses in LLSCC cases.

Subcellular localization and expression of E-cadherin and SNAIL are relevant since early stages of oral carcinogenesis

The biological process of epithelial-to-mesenchymal transition (EMT) has been studied in oral squamous cell carcinoma (OSCC) metastasis, but it is rarely evaluated at several stages of oral carcinogenesis. This study aimed to analyze the presence of SNAIL and E-cadherin proteins, markers of EMT, in the development and progression of OSCC, evaluating excised specimens of potentially malignant lesions (oral leukoplakia with and without dysplasia-OL and OLD, respectively), tumor tissues (OSCC), metastatic lymph nodes (LN), and normal oral mucosa (NOM) by immunohistochemistry, considering subcellular localization. Additionally, SNAIL and E-cadherin transcripts were evaluated in vitro by qPCR, using SCC-9 cell line in comparison to human keratinocytes (HPEC). There was a significant increase in nuclear expression of SNAIL from NOM to OLD followed by a noticeable decrease in nuclear expression accompanied by increased cytoplasmic expression in OSCC (p<0.05). The E-cadherin cytoplasmic expression was remarkable and statistically significant higher in OSCC and LN, both compared to NOM (p< 0.0001), OL (p<0.01) and OLD (p< 0.0001 and p<0.001, respectively). In vitro, E-cadherin and SNAIL transcripts were lower in SCC-9 compared to HPEC cells, although only the decrease of E-cadherin was statistically significant (p<0.05). Regarding the association of E-cadherin and SNAIL expression with the clinical findings, the analysis revealed an association between the cytoplasmic expression of SNAIL and the invasion pattern (p=0.05) in OSCC. The increased nuclear SNAIL expression may be characteristic of OLD, and the presence of E-cadherin in cell cytoplasm a marker of transformation to malignancy of potentially malignant oral leukoplakias into OSCC.

Higher expression of WNT5A protein in oral squamous cell carcinoma compared with dysplasia and oral mucosa with a normal appearance

WNT5A is a secreted signaling protein that promotes migration and invasion of oral squamous cell carcinoma (OSCC) cells through activation of non‐canonical WNT signaling. Here, we examined expression of WNT5A, β‐catenin, and E‐cadherin by immunohistochemistry in 21 human diagnostic incision biopsies that each had regions of oral mucosa with a normal appearance adjacent to the affected tissue, dysplasia, and OSCC. We also investigated the effect of recombinant WNT5A (rWNT5A) on expression of the cell‐adhesion proteins E‐cadherin and β‐catenin by western blot analysis. No expression of WNT5A protein was present in oral mucosa with a normal appearance or in mild grade dysplasia. However, expression of WNT5A increased along with increasing grade of dysplasia, and the highest expression was detected in OSCCs. Expression of membranous β‐catenin and of E‐cadherin was lower, whereas expression of cytoplasmic β‐catenin was higher, in OSCCs than in non‐cancerous regions. However, there was no correlation between expression of WNT5A and expression of either β‐catenin or E‐cadherin. Furthermore, treatment of OSCC cells with rWNT5A had no effect on the expression of β‐catenin or E‐cadherin. Taken together with previous results, we conclude that WNT5A influences the progression of OSCC without affecting the canonical WNT/β‐catenin pathway and without down‐regulating E‐cadherin. WNT5A may have potential as a biological marker for malignant transformation of dysplasia to OSCC.

Semiquantifiable angiogenesis parameters in association with the malignant transformation of oral leukoplakia

BACKGROUND

Aim of the study was to assess the role of angiogenesis in the process of malignant transformation of clinical diagnosed oral leucoplakia (OL).

MATERIALS AND METHODS

A total of 131 histological preparations [oral leukoplakia/hyperkeratosis without dysplasia (OL; n = 49), oral leukoplakia/hyperkeratosis with mild dysplasia (OL-SIN1; n = 33), with moderate dysplasia (OL-SIN2; n = 13) and leukoplakia-derived oral squamous cell carcinoma (OL-OSCC; n = 36)] were evaluated for microvessel density (MVD), vessel diameter as well as for vascular endothelial growth factor (VEGF-A) expression. Data were compared within the groups.

RESULTS

For MVD, there were significant differences between OL and OL-SIN 2/OL-OSCC (P < 0.05) and between OL-SIN 1 and OL-OSCC (P < 0.05). For OL-OSCC, vessel diameters were significantly increased compared with OL (P < 0.05). Expression of VEGF-A increased significantly gradually from OL-SIN 1 to OSCC (each P < 0.05). This was especially evident for lesions of the tongue when compared to the others.

CONCLUSION

Angiogenesis increases during the transition from OL through dysplasia to OL-OSCC. In particular, OL-OSCCs of the tongue, VEGF-A expression may be used for estimation of malignant progression of OL.

Twist and Snail expression in tumor and stromal cells of epithelial odontogenic tumors

BACKGROUND

The aims of this study were to evaluate expression of Twist and Snail in tumor and stromal cells of epithelial odontogenic tumors and to analyze relationships between Twist and Snail expression and between tumor and stromal expression.

METHODS

Immunohistochemistry was performed using Twist and Snail antibodies in 60 ameloblastomas (AMs; 20 solid/multicystic, 20 unicystic, and 20 recurrent), six ameloblastic carcinomas (ACs), 10 adenomatoid odontogenic tumors (AOTs), and six calcifying epithelial odontogenic tumors (CEOTs).

RESULTS

A higher rate of tumor cells strongly positive for Twist was observed in AC compared to the other tumors (P = 0.019). The rate of tumor cells strongly positive for Snail tended to be higher in AC than in AM (P = 0.060). AM and AC showed a higher rate of Twist-positive stromal cells than AOT and CEOT (P < 0.001). Tumor cells of recurrent AM showed stronger expression of Twist (P < 0.001) and Snail (P = 0.001) compared to AM without recurrence. A moderate positive correlation was observed between tumor expression of Twist and Snail (r = 0.376, P = 0.001) and between tumor and stromal expression of Snail (r = 0.334, P = 0.002).

CONCLUSIONS

Twist and Snail may affect the epithelial-mesenchymal transition in AC and be involved in recurrence of AM. Stromal Twist expression may be associated with aggressive clinical behavior of epithelial odontogenic tumors. A Twist-Snail pathway may participate in the development and progression of odontogenic tumors, and tumor-stroma interaction in odontogenic tumors may be mediated by Snail.

Altered β-catenin expression in oral mucosal dysplasia: a comparative study

OBJECTIVE

The current study aimed to investigate the β-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa.

MATERIAL AND METHODS

Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-β-catenin primary antibody. A qualitative β-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher's exact test were used to verify possible differences in the β-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant.

RESULTS

Membranous expression of β-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, β-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic β-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001).

CONCLUSIONS

The β-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.

Is overexpression of TWIST, a transcriptional factor, a prognostic biomarker of head and neck carcinoma? Evidence from fifteen studies

TWIST, a basic helix-loop-helix transcription factor, has been indicated to play a critical role in the progression of numerous malignant disorders. Published data on the significance of TWIST expression in head and neck carcinoma (HNC) risk have yielded conflicting results. Thus, we conducted a quantitative meta-analysis to obtain a precise estimate of this subject. After systematic searching and screening, a total of fifteen studies using immunohistochemistry for TWIST detection were included. The results showed that TWIST positive expression rate in HNC tissues was higher than that in normal tissues. TWIST expression might have a correlation with clinical features such as low differentiation, advanced clinical stage, presence of lymph node metastasis, distant metastasis and local recurrence (P < 0.05) , but not with age, gender, T stage and smoking as well as drinking (P > 0.05). In addition, over-expression of TWIST was a prognostic factor for HNC (HR = 1.92, 95% CI = 1.13–3.25). The data suggested that TWIST might play critical roles in cancer progression and act as a prognostic factor for HNC patients.

E-cadherin regulators are differentially expressed in the epithelium and stroma of keratocystic odontogenic tumors

BACKGROUND

The epithelial-mesenchymal transition (EMT) is the process where cells lose their epithelial features and acquire properties of typical mesenchymal cells. The dissociation of tumor cells due to changes in cell-cell adhesion is one of the key principles of tumor invasion and EMT. Thus, the knowledge of the molecular features of EMT in keratocyst odontogenic tumor (KOT) can provide useful markers to aid in the diagnosis and prognosis and perhaps contribute to an alternative therapeutic approach as it shows an aggressive clinical behavior and high recurrence rates. This study aimed to evaluate the EMT in KOT by the immunoexpression of E-cadherin, N-cadherin, Snail, and Slug and comparing to radicular cysts and dental follicles.

METHODS

Thirty-two KOTs, 15 radicular cysts, and 08 dental follicles were used for immunohistochemistry, evaluating the extent, intensity, labeling pattern, cellular compartment in the epithelium and stroma, and the presence of inflammation.

RESULTS

E-cadherin was preserved in most cases of keratocystic odontogenic tumor. N-cadherin was increased in the tumor epithelium, a result that was positively correlated with the heterogeneous and nuclear immunoexpression of Slug in the epithelium; Slug also correlated with high Snail immunoexpression. N-cadherin was positively correlated with Slug in the stroma of keratocystic odontogenic tumors.

CONCLUSIONS

The high immunoexpression of Snail and nuclear Slug in keratocystic odontogenic tumors suggests these proteins as transcription factors without necessarily participating in 'cadherin switching'. However, the knowledge of their induction of the epithelial-mesenchymal transition in odontogenic tumors is still limited.

sE-cadherin serves as a diagnostic and predictive parameter in prostate cancer patients

BACKGROUND

Measurement of prostate-specific antigen (PSA) advanced the diagnostic and prognostic potential for prostate cancer (PCa). However, due to PSA's lack of specificity, novel biomarkers are needed to improve risk assessment and ensure optimal personalized therapy. A set of protein molecules as potential biomarkers was therefore evaluated in serum of PCa patients.

METHODS

Serum samples from patients undergoing radical prostatectomy (RPE) for biopsy-proven PCa without neoadjuvant treatment were compared to serum samples from healthy subjects. Preliminary screening of 119 proteins in 10 PCa patients and 10 controls was carried out by the Proteome Profiler Antibody Array. Those markers showing distinct differences between patients and controls were then further evaluated by ELISA in the serum of 165 PCa patients and 19 controls. Uni- and multivariate as well as correlation analysis were performed to test the capability of these molecules to detect disease and predict pathological outcome.

RESULTS

Screening showed that soluble (s)E-cadherin, E-selectin, MMP2, MMP9, TIMP1, TIMP2, Galectin and Clusterin warranted further evaluation. sE-Cadherin, TIMP1, Galectin and Clusterin were significantly over- and MMP9 under-expressed in PCa compared to controls. The concentration of sE-cadherin, MMP2 and Clusterin correlated negatively and that of MMP9 and TIMP1 positively with the Gleason Sum at prostatectomy. Only sE-cadherin significantly correlated with the highest Gleason pattern. Compared to serum PSA, sE-cadherin provided an independent and better matching predictive ability for discriminating PCas with an upgrade at RPE and aggressive tumors with a Gleason Sum ≥7.

CONCLUSIONS

sE-cadherin performed most favorably from a large panel of serum proteins in terms of diagnostic and predictive potential in curatively treatable PCa. sE-cadherin merits further investigation as a biomarker for PCa.

PRMT1 Is a Novel Regulator of Epithelial-Mesenchymal-Transition in Non-small Cell Lung Cancer

Protein arginine methyl transferase 1 (PRMT1) was shown to be up-regulated in cancers and important for cancer cell proliferation. However, the role of PRMT1 in lung cancer progression and metastasis remains incompletely understood. In the present study, we show that PRMT1 is an important regulator of epithelial-mesenchymal transition (EMT), cancer cell migration, and invasion, which are essential processes during cancer progression, and metastasis. Additionally, we have identified Twist1, a basic helix-loop-helix transcription factor and a well-known E-cadherin repressor, as a novel PRMT1 substrate. Taken together, we show that PRMT1 is a novel regulator of EMT and arginine 34 (Arg-34) methylation of Twist1 as a unique "methyl arginine mark" for active E-cadherin repression. Therefore, targeting PRMT1-mediated Twist1 methylation might represent a novel strategy for developing new anti-invasive/anti-metastatic drugs. Moreover, methylated Twist1 (Arg-34), as such, could also emerge as a potential important biomarker for lung cancer.

E-cadherin as a potential biomarker of malignant transformation in oral leukoplakia: a retrospective cohort study

Background

Numerous attempts have been made to establish and develop tumor markers that could determine the susceptibility of normal tissues to transform into cancerous ones. To determine whether altered expression patterns of E-cadherin could be an early event in the progression of potentially malignant disorders to oral squamous cell carcinoma, this study aimed to assess the relationship between the immunoexpression of E-cadherin and the different degrees of epithelial dysplasia in oral leukoplakia.

Methods

Surgically excised specimens from patients with oral leukoplakia (n = 31), oral cavity squamous cell carcinoma with cervical lymph node metastasis (n = 12) and normal oral mucosa (n = 9) were immunostained for E-cadherin. Oral leukoplakia samples were distributed into low and high risk group according to a binary system for grading oral epithelial dysplasia. Comparative analyses between E-cadherin expression and microscopic features (WHO histological grading and epithelial dysplasia) were performed by Pearson Chi-square test (P < 0.05).

Results

Differences in E-cadherin expression were observed between normal oral mucosa and low risk oral leukoplakia (P = 0.006), low and high risk oral leukoplakia (P = 0.019), and high risk oral leukoplakia and oral cavity squamous cell carcinoma with cervical lymph node metastasis (P = 0.0001). In addition, as epithelia undergo dysplastic changes, the risk of malignant transformation increases, and there is a reduction or loss of E-cadherin expression by keratinocytes. Reduced E-cadherin expression was an early phenomenon and it was observed in moderate-severe dysplasia, showing that the loss of epithelial cohesion may be an indicator of progression to oral cavity squamous cell carcinoma.

Conclusions

E-cadherin could be used as a novel biomarker to identify lesions with potential risk for malignant transformation, which may provide opportunities for prophylactic interventions in high risk patient groups.