The expression of E-cadherin and cathepsin-D in normal oral mucosa, oral epithelial dysplasia and oral squamous cell carcinoma: A comparative analysis between immunohistochemistry and routine histopathology

Immunohistochemical Evaluation of E- Cadherin in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Background

Cancers arising in the oral cavity are more commonly of squamous cell carcinomas. E-cadherin is a calcium-dependant transmembrane glycoprotein of the type-1 cadherin superfamily is an invasion/tumor suppressor gene, which plays a vital role in epithelial cell-cell adhesion. Epithelial E-cadherin expression loss increases tumor invasiveness and metastasis.

Aim

To determine the expression of E-cadherin in oral epithelial dysplasia (OED) and oral squamous cell carcinoma (OSCC).

Materials and Methods

Analysis of E-cadherin expression in 10 cases of normal mucosa, 15 cases of various grades of OED, 15 cases of OSCC.

Statistical Analysis

The data were calculated using Chi-square test and analysis of variance test (ANOVA).

Results

An intragroup comparison of staining intensity and staining location for OED showed a highly significant difference between mild and moderate grade (P < 0.001). A significant difference of staining intensity was noted among well and moderately differentiated grades, and well and poorly differentiated grades of OSCC. A comparison of staining location among well and poorly differentiated grades of OSCC was found to be significant.

Conclusion

Expression loss is observed as the severity of the lesion progresses in both OSCC and OED. The increased loss of expression in oral squamous cell carcinoma poorer the prognosis.

E-cadherin Expression in Premalignant Lesions, Premalignant Conditions, Oral Squamous Cell Carcinoma, and Normal Mucosa: An Immunohistochemical Study

Background Oral squamous cell carcinoma (OSCC) is a multi-step process. Epithelial-mesenchymal transition (EMT) is an important step in the progression of OSCC. One of the components that influence EMT is E-cadherin. The aim of this study was to determine the expression of E-cadherin in oral submucous fibrosis (OSMF), various grades of epithelial dysplasia, OSCC, and to compare it with the expression in the normal mucosa. Material and methods E-cadherin immunohistochemical detection was done using a monoclonal antibody of clone EP-6TM and the PolyExcel HRP/DAB chromogen detection system. A total of 100 samples, were divided into four groups, which included epithelial dysplasia (group 2) (30 cases), oral submucous fibrosis (group 3) (OSMF-30 cases), and oral squamous cell carcinoma (group 4) (OSCC-30 cases), which was compared with normal mucosa (group 1) (10 cases). The positive control used for E-cadherin was ductal breast carcinoma. Results All the cases of normal mucosa, epithelial dysplasia, and OSMF showed positivity for E-cadherin expression. In OSCC, 97% of cases expressed E-cadherin except one case. Out of 30 cases of epithelial dysplasia, 53% of mild epithelial dysplasia had a moderate intensity of expression and 75% had a mild intensity of E-cadherin expression. In moderately differentiated OSCC, 82% of cases showed mild intensity. Tissue localization of the E-cadherin stain in the basal layer decreased from normal mucosa to grades of epithelial dysplasia and OSCC. The pattern of E-cadherin staining in all the cases of group I, group II, and group III was membranous. In 97% of OSCC cases, both membranous and cytoplasmic staining were seen. Conclusion E-cadherin expression was reduced in increasing grades of epithelial dysplasia, OSCC, and OSMF compared to that of normal mucosa. E-cadherin expression is reduced as the lesions progress to malignancy. Hence, E-cadherin can be considered a surrogate marker of malignancy.

Potentiated action on the progression of OSMF by hypoxia mediated signaling pathway by the epithelial mesenchymal transition and angiogenic apparatus

Background

Epithelial-mesenchymal transition (EMT) is a complex process, in which epithelial cells acquire the characteristics of invasive mesenchymal cells. EMT has been implicated in cancer progression and metastasis as well as the formation of many tissues and organs during development.

Aim

The aim of the study was to ascertain the role of hypoxia-mediated signaling pathways influencing EMT and angiogenesis in progression of oral submucous fibrosis (OSMF).

Materials and Methods

Evaluation of the immunoexpression of alpha-smooth muscle actin (α-SMA), E-cadherin, vimentin, and factor VIII receptor antigen in OSMF and oral squamous cell carcinoma (OSCC) arising from OSMF was done. Differences between the different variables were analyzed using ANOVA test and Pearson's Chi-square test, and Mann-Whitney test was also calculated.

Results

The mean α-SMA positive myofibroblasts increased from Group 1 (OSMF) to Group 2 (OSCC), especially those in the deeper connective tissue stroma. The mean labeling index of vimentin and mean vessel density immunoexpression was more in Group 2 (OSCC) as compared to Group 1 (OSMF). Mean α-SMA correlated negatively with E-cadherin expression and positively with vimentin and factor VIII immunoexpression. E-cadherin expression correlated negatively with factor VIII and positively with Vimentin expression.

Conclusions

The molecular mechanisms responsible for the development of OSCC in patients with OSMF require unification of multiple progressive pathogenetic mechanisms involved in the progression of the disease.

Evaluation of e-cadherin and vimentin expression for different grades of oral epithelial dysplasia and oral squamous cell carcinoma - An immunohistochemical study

Background

Oral cancer is the 11^thcommon cancer in the world and ranks 6^thglobally in deaths. The incidence of oral cancer in India accounts for approximately 30%-40% of all cancers.

Aims and Objective

The present study was undertaken to evaluate the expression of Vimentin and E-cadherin in different grades of oral epithelial dysplasias (OEDs) and oral squamous cell carcinoma (OSCC).

Materials and Methods

Biopsies/blocks of oral cavity lesions were retrieved from the archives of the department. Normal oral mucosa (5 cases), oral epithelial dysplastic (60 cases) and different grades of OSCC (60 cases) evaluated by hematoxylin and eosin sections. Immunohistochemical analysis was done on the blocks and expression of E-cadherin and Vimentin was recorded.

Results

Our study included various grades of OED, OSCC and normal mucosa as control cases. The mean age of OED and OSCC was 49 and 56 years, respectively, with male predominance. Tobacco habit was present in approximately 90% cases, and buccal mucosa was the most commonly involved site in oral cavity with whitish patch and ulceroproliferative lesions being the common clinical presentations respectively. In OED, downregulation and altered localization of e-cadherin (81.6%) and increased expression of vimentin (52.3%) along with their concurrent increase in the stroma represent epithelial mesenchymal transition. In OSCC, reduction in expression (<50%) for e-cadherin (56.6%) with altered localization for e-cadherin was seen in 88.3% of OSCC along with neoexpression of vimentin in the epithelial cells was seen in 68.3% suggestive of mesenchymal phenotypic modification (P = 0.05).

Conclusion

It is very crucial to evaluate the invasiveness of dysplasia and tumor with specific molecular biomarker that may help in early prediction of malignancy and also guide in deciding best treatment strategy for established cases of malignancy.

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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Epithelial oral mucosal cells: Do they behave differently when exposed to oral carcinogens?

OBJECTIVE

To assess the level of maturation and proliferation of epithelial cells and the correlation with immunocytochemical expression of adhesion (E-cadherin) and cell differentiation (involucrin) markers.

METHODS

Cytopathological samples were obtained from four groups of patients: control (CG, n=30); alcohol/tobacco (ATG, n=31), leucoplakia (LG, n=31), and squamous cell carcinoma (SCCG, n=22). Cytopathological smears were collected from all groups for AgNOR, Papanicolaou and immunocytochemical staining.

RESULTS

There was an increase in anucleated cells in ATG compared to CG and in LG compared to lesion-free groups (P<.05). In addition, there was a higher rate of intermediate cells in lesion-free groups than in LG (P=.001). When these findings were correlated with positive E-cadherin expression, there was a smaller number of anucleated and intermediate cells (P<.05). The proliferation rate was higher in the SCCG than in the CG (P<.05) and in the ATG compared to LG (P<.05). Moreover, cell proliferation increased in the presence of positive E-cadherin expression in the ATG and LG. No statistically significant results were obtained for involucrin analysis.

CONCLUSION

Cytopathology combined with quantitative techniques such as Papanicolaou, AgNOR, and immunocytochemical expression of E-cadherin detects changes associated with oral carcinogenesis. The innovative approach used in this study allows assessing the expression of cell adhesion (E-cadherin) and differentiation (involucrin) markers by means of oral mucosal cytopathology. The E-cadherin imunocytochemical expression indicated changes associated with the oral carcinogenesis process. An increase in cell proliferation rate in oral squamous cell carcinoma group was associated with the lower immunoexpression of E-cadherin. Cytopathology combined with quantitative techniques and immunocytochemical expression of E-cadherin may detect early alterations associated with oral carcinogenesis.

Immunohistochemical Expression of Cathepsin D in Primary and Recurrent Squamous Cell Carcinoma

AIM

The aim of this study is to analyze and compare the immunohistochemical expression of cathepsin B in primary oral squamous cell carcinoma (OSCC) and recurrent OSCC.

MATERIALS AND METHODS

A total of 50 cases were studied immunohistochemically for rabbit polyclonal antihuman cathepsin D expression. A total of 10 cases of breast carcinoma were taken as positive controls. Immunohistochemical staining was performed using labeled streptavidin-biotin technique.

RESULTS

All the 45 cases of OSCC, both primary and recurrent cases included, showed varying grades of cathepsin D immu-noreactivity. Statistical significance at 5% level was observed in cathepsin D expression between the different grades of well, moderate, and poorly differentiated primary squamous cell carcinomas. In the comparison of cathepsin D staining intensity among primary squamous cell carcinomas with and without recurrence, a statistical significance between the groups was observed when the p-value was at 10%, but the same comparison was not significant when the p-value was at 5%.

CONCLUSION

Cathepsin D expression in primary squamous cell carcinomas with recurrences was very variable as compared with primary squamous cell carcinomas without recurrences. Comparison of cathepsin D expression in primary with their recurrent counterparts showed mostly similar intensity of expression in recurrent carcinomas, thus suggesting its limited usefulness in predicting recurrence.

CLINICAL SIGNIFICANCE

Although cathepsin D might have shown limited usefulness in predicting cancer recurrence, it, however, is a proven valuable tool to detect the aggressiveness of various other tumors, and if corroborated with a larger sample may hold the key to early, more effective, and more specific treatment modalities for cases of oral cancer also.

Expression of small leucine-rich extracellular matrix proteoglycans biglycan and lumican reveals oral lichen planus malignant potential

OBJECTIVES

The aim of this study was to examine molecular alterations on the protein level in lesions of oral lichen planus (OLP), oral squamous cell carcinoma (OSCC) and healthy mucosa.

MATERIALS AND METHODS

Global protein profiling methods based on liquid chromatography coupled to mass spectrometry (LC-MS) were used, with a special emphasis on evaluation of deregulated extracellular matrix molecules expression, as well as on analyses of IG2F and IGFR2 expression in healthy mucosa, OLP and OSCC tissues by comparative semi-quantitative immunohistochemistry.

RESULTS

Mass spectrometry-based proteomics profiling of healthy mucosa, OLP and OSCC tissues (and accompanied histologically unaltered tissues, respectively) identified 55 extracellular matrix proteins. Twenty among identified proteins were common to all groups of samples. Expression of small leucine-rich extracellular matrix proteoglycans lumican and biglycan was found both in OSCC and OLP and they were validated by Western blot analysis as putative biomarkers. A significant increase (p < 0.05) of biglycan expression in OLP-AT group was determined in comparison with OLP-T group, while lumican showed significant up-regulation (p < 0.05) in OLP-T and OSCC-T groups vs. adjacent and control tissue groups. Biglycan expression was only determined in OSCC-AT group. Immunohistochemical analysis of IGF2 and IG2FR expression revealed no significant difference among groups of samples.

CONCLUSION/CLINICAL RELEVANCE

Biglycan and lumican were identified as important pathogenesis biomarkers of OLP that point to its malignant potential.

Expression of E-cadherin and involucrin in leukoplakia and oral cancer: an immunocytochemical and immunohistochemical study

To assess the immunocytochemical and immunohistochemical correlation of adhesion (E-cadherin) and cell differentiation (involucrin) molecules in oral leukoplakia and oral squamous cell carcinoma. Cytological samples and biopsies were obtained from male and female patients aged over 30 years with oral leukoplakia (n = 30) and oral squamous cell carcinoma (n = 22). Cell scrapings and the biopsy were performed at the site of the lesion and histological slides were prepared for the immunocytochemical analysis of exfoliated oral mucosal cells and for the immunohistochemical analysis of biopsy tissues using E-cadherin and involucrin. Spearman's correlation and kappa coefficients were used to assess the correlation and level of agreement between the techniques. Immunostaining for E-cadherin and involucrin by both techniques was similar in the superficial layers of the histological sections compared with cell scrapings. However, there was no statistical correlation and agreement regarding the immunocytochemical and immunohistochemical expression of E-cadherin and involucrin in oral leukoplakia (R = 0.01, p = 0.958) (Kappa = 0.017, p = 0.92) or in oral squamous cell carcinoma (R = 0.26, p = 0.206) (Kappa = 0.36, p = 0.07). The immunoexpression of E-cadherin and involucrin in tissues is consistent with the expression patterns observed in exfoliated oral mucosal cells, despite the lack of a statistically significant correlation. There is an association of the histopathological characteristics of leukoplakia with the expression E-cadherin and of the microscopic aspects of oral squamous cell carcinoma with immunohistochemical expression of involucrin.

Human telomerase reverse transcriptase (hTERT) promotes cancer invasion by modulating cathepsin D via early growth response (EGR)-1

Human telomerase reverse transcriptase (hTERT) contributes to tumor progression as well as maintaining telomere length, however, the mechanism by which hTERT promotes invasiveness is not yet completely understood. This study aims to unravel the precise mechanism through which hTERT promotes cancer invasion. We established an hTERT-overexpressed immortalized cell line (IHOK/hTERT). In orthotopic xenograft models, IHOK/hTERT harbors higher tumorigenicity than IHOK/Control. IHOK/hTERT showed much higher migration and invasion activities compared to IHOK/Control. IHOK/hTERT co-cultured with fibroblasts displayed increased invasion compared to IHOK/hTERT without fibroblasts. We screened for genes that play an important role in intermodulation between cancer cells and fibroblasts using a microarray and identified fibroblast activation protein (FAP). hTERT knockdown showed decreased expression of FAP and early growth response (EGR)-1, one of the transcriptional regulators of FAP in IHOK/hTERT and oral cancer cell line YD10B. Furthermore, EGR-1 knockdown in IHOK/hTERT and YD10B showed reduced invasion and reduced cathepsin D expression compared to Control-siRNA cells. Taken together, this study provides evidence that hTERT overexpression is responsible for the upregulation of the cysteine protease cathepsin D by regulating EGR-1 to activate invasiveness in cancer progression.

Expression of E-cadherin in normal oral mucosa, in oral precancerous lesions and in oral carcinomas

Objective:

The aim of the present study was to assess the expression of E-cad in oral precancerous lesions and conditions and oral carcinomas in comparison with normal mucosa.

Materials and Methods:

Total of 50 samples were selected for the study and were categorized into five groups and 10 samples in each group as Group I-oral leukoplakia (OL), Group II-oral lichen planus (OLP), Group III-oral submucous fibrosis (OSMF), Group IV-oral squamous cell carcinoma (OSCC) and Group V-normal oral mucosa (NOM) as control group. All the samples were assessed for the expression of E-cad by immunohistochemical study.

Results:

Upon assessing the expression of E-cad in OL, OSMF, OLP and OSCC, as majority of the samples with OSCC (90%), OL (80%), OLP (70%) and OSMF (60%) showed mild to moderate expression of E-cad staining, which was suggestive of reduction in dysplastic cells on comparison to NOM cells. This difference in expression and variation of E-cad upon comparison with normal mucosa was statistically significant (P < 0.001).

Conclusion:

There is significant (P < 0.001) variation of expression of E-cad with the histopathological dysplasia of the oral precancerous lesions and conditions, and the tumor differentiation of the oral cancers. However, there was no correlation of the degree of loss of expression of E-cad with the degree of dysplasia or the tumor differentiation of oral cancers. We conclude with our study that, there is a variation in the expression of E-cad but its value as a prognostic marker is questionable.

Evaluation of Docetaxel-Sensitive and Docetaxel-Resistant Proteomes in PC-3 Cells

OBJECTIVES

Docetaxel was the first drug with proven survival benefit in men with castration-resistant prostate cancer. Acquired resistance to docetaxel precedes fatality in castration-resistant prostate cancer. The aims of this study were to evaluate docetaxel-sensitive and docetaxel-resistant proteomes in PC-3 cells, and to investigate the molecular mechanism of docetaxel-resistant PC-3 cells.

METHODS

Docetaxel-resistant PC-3 cells were developed by docetaxel dose escalation. The global profiling of the protein expression was investigated in docetaxel-sensitive and docetaxel-resistant proteomes in PC-3 cells using 2-dimensional polyacrylamide gel electrophoresis/matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.

RESULTS

Forty-nine differential proteins were found in docetaxel-resistant PC-3 cells in comparison with docetaxel-sensitive PC-3 cells. Expression in 29 proteins was upregulated, whereas expression in 20 proteins was downregulated. ATP synthase and galectin-1 were involved in the formation of tumor vessels; calreticulin, cathepsin D, and cofilin were involved in tumor metastasis, and GRP78 (78-kDa glucose-regulated protein) and microtubule-associated protein-6 were involved in drug resistance of tumor.

CONCLUSION

It is suggested that a proteomic expression difference exists between docetaxel-sensitive and docetaxel-resistant PC-3 cells, which would be helpful for further understanding the molecular mechanisms of docetaxel resistance in PC-3 cells.