Ki-67 Prognostic Value in Different Histological Grades of Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Introduction: Abnormal cell proliferation appears to be a possible predictor of tumorigenesis, Ki-67 proteinexpression is closely related to the cell proliferation and could be used as a biomarker for the growth in the most ofhuman tumors. The aim of the study: Investigating of Ki-67 expression in the pathological grades of oral epithelialdysplasia and oral squamous cell carcinomas. Materials and Methods: The sample consisted of 30 formalin-fixed,paraffin-embedded specimens of oral epithelial dysplasia (OED), 30 other of oral squamous cell carcinomas (OSCC), and10 normal oral epithelium (NOE) were conventionally stained with hematoxylin and eosin and immunohistochemicallystained with Ki-67 monoclonal antibody. Results: Expression of Ki-67 was restricted to the basal layers in the normaloral epithelium whereas Ki-67 positive cells in oral epithelial dysplasia (OED) were located in the basal, suprabasaland spinous layers, Ki-67 expression was increased in high-risk cases. Ki-67 positive cells in well-differentiated(OSCC) were located mainly in the periphery of the tumor nests, in moderately-differentiated (OSCC) were locatedin both peripheral and part of a center of the tumor nests whereas it was diffused in most of the Poorly-differentiated(OSCC). Statistical analysis indicated a significant difference between the expression in (OED) and (NOE), (OSCC)and (NOE), and no differences between (OED) and (OSCC). Conclusion: This study has concluded that Ki-67 antigencould be used as a marker for the histological grading of OED and OSCC, Expression of Ki 67 increased according tothe severity of oral epithelial dysplasia.     

Immunohistochemical Evaluation of Glucose Transporter Type 1 in Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity and some of these have been documented in association or preceded by oral epithelial dysplasia (OED). Aggressive cancers with fast growth have demonstrated overexpression of some glucose transporters (GLUTs). Thus, the aim of this study was to analyze the immunohistochemical expression of the glucose transporter, GLUT-1, in OEDs and OSCCs, seeking to better elucidate the biological behavior of neoplasias. Fifteen cases were selected this research of both lesions. Five areas were analyzed from each case by counting the percentage of positive cells at 400x magnification. Immunoreactivity of GLUT-1 was observed in 100% of the samples ranging from 54.2% to 86.2% for the OSCC and 73.9% to 97.4% for the OED. Statistical test revealed that there was greater overexpression of GLUT-1 in OED than the OSCC (p=0.01). It is believed the high expression of GLUT-1 may reflect the involvement of GLUT-1 in early stages of oral carcinogenesis.     

Immunohistochemical Evaluation of GLUT-3 and GLUT-4 in Oral Epithelial Dysplasia and Oral Squamous Cell Carcinoma

Objectives: To evaluate immunohistochemically the expression of GLUT-3 and GLUT-4 in oral epithelial dysplasia(OED) and the oral squamous cell carcinoma (OSCC) and assess possible involvement in the malignant transformation oforal lesions. Methods: Tissue samples of 15 cases of OSCC and 15 of OED were subjected to immunohistochemistrywith anti-GLUT-3 and anti-GLUT-4 antibodies. Five fields of each case were analyzed, to provide percentages ofpositive cells at 400X magnification. Result: GLUT-3 and GLUT-4 were positive in 100% of the analyzed samples,the percentage immunolabeling for GLUT-3 ranging from 19% to 73% in the OED group and 10% to 89% in the OSCCgroup. Positive immunolabeling for GLUT-4 ranged from 15.2% to 79.9% in the OSCC group and 27.1% to 92.6% inthe OED group. Statistical analysis with the Mann-Whitney test revealed that there was a higher expression of GLUT-4 inthe OED group than in the OSCC group (p=0.04) without any significant difference in the GLUT-3 expression (p=0.852).Conclusion: GLUT-4 expression may indicate some role in oncogenic mechanisms which can determine a malignantphenotype. Thus, it is suggested that further studies on the role of GLUT-3 in oral carcinogenesis be conducted.     

Salivary Tumour Necrosis Factor-α as a Biomarker in Oral Leukoplakia and Oral Squamous Cell Carcinoma

Background: Oral cancer is one of the life threatening disease which requires an availability of a biomarker for itsearly detection and also for effective treatment strategies. The current study is done to evaluate the efficacy of one suchbiomarker i.e. TNF- α as an indicator for oral precancer and oral cancer. Objectives: To evaluate the efficacy of Tumournecrosis factor - alpha (TNF)-α as a salivary biomarker in histopathologically diagnosed cases of oral leukoplakia andOral squamous cell carcinoma. To correlate the levels of TNF- α with varying histologic grading in Oral SquamousCell Carcinoma and dysplasia grading in Oral leukoplakia or Hyperkeratosis. Materials and Methods: The studygroup included 90 subjects that were divided into three groups. OSCC (n=30), leukoplakia (n=30) and controls (n=30).Cases were selected based on inclusion and exclusion criteria of the study. Salivary samples were then collected fromall three groups. Salivary levels of TNF-α were estimated using Enzyme Linked Immunosorbent Assay (ELISA). Thedata on concentration gradients obtained were subjected to appropriate statistical analysis. Results: The results of thepresent study demonstrated higher levels of salivary TNF-α in individuals with OSCC compared to leukoplakia andhealthy control subjects with a high level of statistical significance. ROC curve analysis along with diagnostic parametercalculation also revealed that salivary TNF-α to be a better medium for detecting OSCC. There is also an increase inthe salivary TNF-α levels with increase in the histological grade of differentiation in OSCC as well as leukoplakia.Conclusion: The present study concludes that salivary TNF – α can be used as a prognostic biomarker of OSCC. Inview of the elevated levels of TNF – α in saliva of individuals with severe dysplasia, it can also be used to monitor themalignant transformation to leukoplakia to OSCC.     

Comparison of PD-L1 Expression in Oral Squamous Cell Carcinoma and Premalignant Lesions of Oral Cavity

Objective: Objectives of this study were to compare  expression of Programmed Death-Ligand 1(PD-L1) protein in oral squamous cell carcinoma (OSCC) and oral potentially malignant disorder (OPMD) cases; and to compare the PD-L1 protein expression in histological grades of OSCC and also in OPMD’s with Dysplasia and without Dysplasia. Materials & Methods: In this study,  25 cases of Oral squamous cell carcinoms, 25 cases of Oral Potentially Malignant Disorders and 10 cases of non-neoplastic oral mucosa (control) cases were included. FFPE blocks of OSCC and OPMD cases were contributed by Department of Pathology, Histopathology Division,Pakistan Institute of Medical Sciences, Islamabad. Immunohistochemical staining of cases with PD-L1 monoclonal antibody (1:100; Dako) was carried out at Histopathology division , PMC Labs,  Peshawar Medical College,Peshawar, Riphah International University, Islamabad . Epithelial cells (membranous and cytoplasmic) positivity was observed for PD-L1 Antibody. Data was analyzed in SPSS version20. For qualitative variables frequencies and percentages were calculated whereas for quantitative variables means and standard deviations were recorded. The Chi-square test was applied to evaluate the significant difference in categorical variables . p-value of ≤0.05 was taken as significant. Results: PD-L1 expression in OSCC cases turned out to be 48% (n=12/25) as compared to 8% of OPMD cases (n=2/25) with a significant p value of 0.002 and all non-neoplastic oral mucosa cases were negative. PD-L1 expression in high grade OSCC cases was quite high (61% n=11/18) as compared to low grade OSCC (14% n=1/7) cases with a significant p value of 0.035. Conclusion: A statistically significant increased PD-L1 expression was noted in  OSCC as compared to OPMD. Expression of PD-L1 was more intense in high grade OSCC cases. The relation of PD-L1 expression to age ,gender or location of OSCC and OPMD cases , and presence of dysplasia in OPMD cases was statistically not significant.     

Stathmin guides personalized therapy in oral squamous cell carcinoma

The survival benefit from docetaxel, cisplatin and 5‐fluorouracil (TPF) induction chemotherapy in oral squamous cell carcinoma (OSCC) patients is not satisfactory. Previously, we identified that stathmin, a microtubule‐destabilizing protein, is overexpressed in OSCC. Here, we further investigated its role as a biomarker that impacts on OSCC chemosensitivity. We analyzed the predictive value of stathmin on TPF induction chemotherapy and its impact on OSCC cell chemosensitivity. Then, we further investigated the therapeutic effects of the combination therapy of TPF chemotherapy and PI3K‐AKT‐mTOR inhibitors in vitro and in vivo. We found that OSCC patients with low stathmin expression benefited from TPF induction chemotherapy, while OSCC patients with high stathmin expression could not benefit from TPF induction chemotherapy. Stathmin overexpression promoted cellular proliferation and decreased OSCC cell sensitivity to TPF treatment. In addition, inhibition of the PI3K‐AKT‐mTOR signaling pathway decreased stathmin expression and phosphorylation. The combination therapy of TPF chemotherapy and PI3K‐AKT‐mTOR inhibitors exhibited a potent antitumor effect both in vitro and in vivo. Therefore, stathmin can be used as a predictive biomarker for TPF induction chemotherapy and a combination therapy regimen based on stathmin expression might improve the survival of OSCC patients.     

Expression of Ki67 Biomarker in Oral Submucous Fibrosis with Clinico-Pathological Correlations: A Prospective Study

Objectives: Oral Submucous Fibrosis (OSMF) is potentially malignant disorder known to transform into oral cancer. The aim of this study is to determine the degree and pattern of expression of aberrant Ki67 in OSMF, oral squamous cell carcinoma (OSCC) and in normal oral mucosa  patients (NOM). The objective is to correlate between Ki67 expression and degree of dysplasia in OSMF patents and also Ki67 expression with clinical and histological grading of OSMF and OSCC patient. Materials and Methods: A prospective cross-sectional study was conducted with purposive sampling technique from Jan 2017 to April 2020.The study groups consist of 35 OSMF cases, 10 cases of each OSCC and NOM. The samples were immunohistochemically analyzed for expression Ki67 antigen using chi-square test (P < 0.05). Results: The expression of Ki67 was significantly higher in OSMF than that of NOM samples, but less than that of OSCC samples. Present study showed correlation between expression of Ki67 with clinical staging and histological grading both in OSMF and OSCC patients. Conclusion: The study demonstrated a high incidence of Ki67 over expression in, OSMF and OSCC. Hence, Ki-67 can be widely used as a proliferation marker to measure growth fraction of cells in OSMF and also for determining the severity of epithelial dysplasia.     

Efficacy of Glucose Starvation of Cancer Cells in the Progress of Oral Squamous Cell Carcinoma Induced in Hamster

Background and aim of the study: Oral squamous cell carcinoma (OSCC) is the most common form of oral cancer, showing poor prognosis and high mortality. Meanwhile, cancer metabolism is an essential contributor to its progression and response to treatment. This research aims to investigating the effect of a glucose-rich and glucose-free diet on the progress of oral squamous cell carcinoma induced in hamsters. Materials and Methods: forty Syrian Hamsters were incubated in two groups. The first one consisted of twenty hamsters, in which the carcinogenic material (DMBA) was applied in the buccal pouch of the hamster three days per week with a glucose-rich diet). The second one was composed of twenty hamsters, in which the carcinogenic material (DMBA) was applied in the buccal pouch three days per week with a glucose-free diet). Hamsters in both groups were sacrificed in groups of five hamsters at a time and at intervals (two weeks, six weeks, ten weeks, and Fourteen weeks). A histological study was performed after conventional staining with hematoxylin and eosin was done. Results: After two weeks of the experiment hyperplasia, mild dysplasia, and moderate dysplasia were recorded in hamster buccal pockets with a glucose-rich diet, and after six weeks moderate dysplasia, severe dysplasia, and carcinomas in situ were recorded, after ten weeks severe dysplasia, carcinomas in situ, and OSCC, after fourteen weeks OSCC were recorded. While with a glucose-free diet Hyperkeratosis, hyperplasia, and mild dysplasia were observed after a two-week the experiment,  after six weeks, mild dysplasia, moderate dysplasia, and severe dysplasia were recorded, after ten weeks, moderate dysplasia, severe dysplasia, and carcinoma in situ, after fourteen weeks Severe dysplasia, carcinoma in situ, and OSCC were reported. Conclusion: our results showed that a glucose-free diet slightly prevents oral squamous cell carcinoma, It may be a supportive treatment in addition to conventional cancer treatment.     

Stathmin基因在人成骨肉瘤细胞中的表达及意义

stathmin作为细胞信号转导分子在细胞分化及恶性肿瘤发生、发展上发挥重要作用。本研究旨在探讨Stathmin基因在人成骨肉瘤细胞中的表达,并探讨阻断其表达对该肿瘤细胞的生物学行为的影响。方法：RT-PCR及原位杂交法检测2个人成骨肉瘤细胞系及45例人成骨肉瘤组织中Stathmin基因表达情况;以高表达Stathmin基因的人成骨肉瘤细胞系SOSP-9607为靶细胞、反义Stathmin(ASODN)为阻断剂,通过MTT实验观察ASODN对该细胞系的生长抑制作用,并用流式细胞仪分析其对细胞增殖周期的影响。     

Genetic Abnormalities in Oral Leukoplakia and Oral Cancer Progression

Background: The cancer progression of oral leukoplakia is an important watchpoint in the follow-up observation of the patients. However, potential malignancies of oral leukoplakia cannot be estimated by histopathologic assessment alone. We evaluated genetic abnormalities at the level of copy number variation (CNV) to investigate the risk for developing cancer in oral leukoplakias. Materials and Methods: The current study used 27 oral leukoplakias with histological evidence of dysplasia. The first group (progressing dysplasia) consisted of 7 oral lesions from patients with later progression to cancer at the same site. The other group (non-progressing dysplasia) consisted of 20 lesions from patients with no occurrence of oral cancer and longitudinal follow up (>7 years). We extracted DNA from Formalin-Fixed Paraffin-Embedded (FFPE) samples and examined chromosomal loci and frequencies of CNVs using Taqman copy number assays. Results: CNV frequently occurred at 3p, 9p, and 13q loci in progressing dysplasia. Our results also indicate that CNV at multiple loci–in contrast to single locus occurrences–is characteristic of progressing dysplasia. Conclusions: This study suggests that genetic abnormalities of the true precancer demonstrate the progression risk which cannot be delineated by current histopathologic diagnosis.     

Stathmin is a Marker of Progression and Poor Prognosis in Esophageal Carcinoma

Stathmin, also called oncoprotein 18, is a founding member of the family of microtubule-destabilizing proteinsthat play a critical role in the regulation of mitosis. At the same time stathmin has been recognized as one ofresponsible factors in cancer cells. The aim of this study was to assess stathmin status, its correlations withclinicopathological parameters and its role as a progosnostic marker in EC patients. The protein and mRNAlevels of stathmin were examined byimmunohistochemistry (IHC) and in situ hybridization in 100EC tissuesand adjacent noncancerous tissues. mRNA and protein expression of stathmin in three EC cell lines(EC9706,ECa109, EC1 commonly used in research) were also analyzed using immunocytochemistry, western blot andin situ hybridization. The prognostic value of Stathmin expression within the tumor tissues were assessed byCox regression and Kaplan-Meier analysis. We showed that stathmin expression was significantly higher in ECtissues than in adjacent noncancerous tissues. High stathmin immunostaining score in the EC was positivelycorrelated with tumor differentiation, Tumor invasion, Lymph node metastases, and TNM stage. In addition, wedemonstrated that three EC cell lines examined, were constitutively expressing a high level of stathmin. Of those,EC-1 showed the strongest mRNA and protein expression for the stathmin analyzed. Kaplan-Meier analysisshowed that significantly longer 5-year survival rate was seen in EC patients with high Stathmin expression,compared to those with low expression of Stathmin expression. Furthermore, multivariate Cox proportionalhazard analyses revealed that Stathmin was an independent factors affecting the overall survival probability.In conclusion, our data provide a basis for the concept that stathmin might be associated with EC developmentand progression.. High levels of Stathmin expression in the tumor tissues may be a good prognostic marker forpatients with EC.     

Nuclear localization of annexin A1 is a prognostic factor in oral squamous cell carcinoma

BACKGROUND AND OBJECTIVES: To investigate whether annexin A1 (ANXA1) expression is a marker in predicting the prognosis of oral cancer patients. METHODS: We immunohistochemically examined the expression of ANXA1 in 66 cases of oral epithelial dysplasia (OED) and 115 cases of oral squamous cell carcinoma (OSCC). The results were correlated with the clinicopathological parameters of tumors and overall patient survival. RESULTS: In normal oral mucosa, ANXA1 staining was predominantly located on the cell membrane. In OED and OSCC specimens, membranous staining decreased, whereas nuclear staining increased. Positive nuclear staining was observed in 9 of 66 (13.64%) OED cases and 63 of 115 (54.8%) OSCCs. Kaplan-Meier curves showed that OSCC patients with ANXA1 nuclear staining had significantly shorter overall lengths of survival (P = 0.00036 by the log-rank test). Multivariate analysis showed that ANXA1 nuclear staining is a significant predictor of poor overall survival. And oral cancer SAS cells treated with hepatocyte growth factor (HGF) can induce ANXA1 protein translocation from cytoplasm to nucleus. Cells pretreated with LY294002 (PI3K inhibitor) almost completely inhibited (88.3% inhibition) HGF-mediated ANXA1 nuclear translocation. CONCLUSIONS: The nuclear localization of ANXA1 protein is a frequent event and could be used as a prognostic factor in OSCC.     

Expression of Matrix Metalloproteinase-10 at Invasive Front of Squamous Cell Carcinoma and Verrucous Carcinoma in the Oral Cavity

Background: Matrix metalloproteinases (MMPs) are a family of zinc metalloproteinases capable of degradingcomponents of connective tissues. MMP-10 is frequently expressed in human cancers. The aim of this studywas to immunohistochemically evaluate its expression in oral squamous cell carcinoma (OSCC) and verrucouscarcinoma (OVC). Materials and Methods: A retrospective analysis of 73 samples (31 OSCC, 22 OVC and 20non-neoplastic epithelium) was performed. All samples were immunohistochemically stained with monoclonalMMP-10 antibody and expression levels and staining intensity were evaluated with respect to microscopicfeatures. Data were analyzed by SPSS (V.21), Mann-Whitney and Kruskal Wallis tests. Results: MMP-10 wasdetected in all OSCC and OVC cases. The expression of MMP-10 in OSCC was intensive (score 3) and in OVCwas low and moderate (score 1 and score 2) more frequently. Non- neoplastic epithelium did not show MMP-10expression. Differences between groups was statistically significant (p<0.05). However, the expression of MMP-10 was not obviously different between various grades of OSCC. Conclusions: According to our study, MMP-10protein can be important possible factor in the transformation of normal oral epithelium to OVC and OSCC,also the level of MMP-10 expression at invasion front of the lesions can be helpful in the differentiation of OVCand OSCC.     

Expression of Mcm2, geminin and Ki67 in normal oral mucosa, oral epithelial dysplasias and their corresponding squamous-cell carcinomas

Proteins necessary for the normal regulation of the cell cycle include minichromosome maintenance protein 2 (Mcm2) and geminin. These are overexpressed in several premalignant and malignant tumours. The Mcm2/Ki67 ratio can be used to estimate the population of cells that are in early G₁ (licensed to proliferate), and the geminin/Ki67 ratio can determine the relative length of G₁. A high ratio indicates a short G₁ and a high rate of cell proliferation. Mcm2 and geminin have been scarcely explored in oral epithelial dysplasia (OED) and oral squamous-cell carcinoma (OSCC). The purpose of this study was to identify the expression pattern of Mcm2, Ki67 and geminin in normal oral mucosa (NOM), OED and their subsequent OSCC, to determine if expression could help predict the prognosis of OED. Paraffin sections of 41 OED cases that progressed to carcinoma, 40 OED without malignant progression, 38 OSCC and 15 NOM were immunostained with antibodies against Mcm2, geminin and Ki67. Labelling indices (LIs) increased progressively from NOM, OED and OSCC (Mcm2, P<0.001; geminin, P<0.001 and Ki67, P<0.001). In all the OED cases (n=81) the levels of expression of Mcm2 (LI, 73.6), geminin (LI, 24.4) and Ki67 (LI, 44.5) were elevated indicating a constant cell-cycle re-entry. When the OED groups were compared, Mcm2 protein expression was higher in the OED with malignant progression (P=0.04), likewise there was a significant increase in the Mcm2/Ki67 and geminin/Ki67 ratios (P=0.04 and 0.02 respectively). Mcm2 and geminin proteins seem to be novel biomarkers of growth and may be useful prognostic tools for OED.     

Diagnostic Utility of Cytology in Assessment of Ploidy Status in Potentially Malignant Oral Disorders

Introduction: Oral leukoplakia, the most common potentially malignant oral disorder (PMOD) may progress to oral squamous cell carcinoma (OSCC). Although, the current standard of care for assessing its malignant potential remains histological examination and assessing the severity of dysplasia, DNA ploidy analysis has been suggested as a surrogate marker to predict the behaviour of PMODs. Objectives: To detect aneuploidy and to correlate ploidy status with different grades of dysplasia in both tissue and cytology samples to predict the behaviour of these potentially malignant disorders and to assess the diagnostic utility of cytology samples for ploidy analysis. Methodology: After obtaining ethical clearance and consent, tissue and cytology samples of leukoplakia were collected and grouped based on the dysplastic findings into low-risk (n=20) and high-risk (n=20). DNA ploidy analysis was done using high resolution flow cytometry and its diagnostic utility was assessed. Results: Diagnostic utility was expressed in terms of sensitivity, specificity, PPV and NPV. On comparing the ploidy status of individual cases between tissue and cytology samples, cytology was able to accurately determine the ploidy status in majority of the cases. In the low-risk group, cytology had a sensitivity and specificity of 100% and a PPV and NPV of 100% with an overall diagnostic accuracy of 100%. Among the high-risk group, cytology had a sensitivity of 80% and specificity of 100% with a PPV of 100% and NPV of 83.33% and had an overall diagnostic accuracy of 90%. Combining both groups together, it had a sensitivity of 85.71% and specificity of 100% with a PPV of 100% and NPV of 92.31% and had an overall diagnostic accuracy of 94.74%. Conclusion: Overall, this study showed a positive correlation between cytology and tissue samples and ploidy and grade of dysplasia and cytology proved to be a simple and efficient with a reasonable diagnostic value.     

Oral yeast carriage correlates with presence of oral epithelial dysplasia

Previous studies have suggested a link between the presence of Candida albicans and the development of oral squamous cell carcinoma (OSCC). The aim of the present study was to assess the presence and level of colonisation of oral yeast in patients undergoing an incisional oral mucosal biopsy in order to assess whether the amount of oral yeast present correlated with the presence and degree of oral epithelial dysplastic or neoplastic change. Two hundred and twenty-three patients who were undergoing an incisional biopsy for the diagnosis of an oral mucosal lesion were enrolled in this study. Mouth swills were obtained from each patient for the presence and amount of oral yeast present. Some of the patients (44.6%) had a histopathological diagnosis of either oral epithelial dysplasia (OED) or OSCC and the frequency of oral yeast carriage was significantly greater (P<0.001) in these patients than those without histopathologically detected dysplastic or neoplastic oral lesions. Furthermore, significantly (P<0.001) more patients with OED or OSCC had a higher number of yeast (over 1000 cfu/ml) in their oral cavity than patients without any evidence of epithelial dysplasia or neoplasia histopathologically. The degree of epithelial dysplasia present in these patients also correlated with higher amounts of yeast in the oral cavity (P=0.017). The results of the present study reveal that there is an interaction between oral carriage of yeast and oral epithelial dysplasia, however it remains unclear how yeast infection influences the development and progression of dysplasia.     

Suitability/Unsuitability of Cell Proliferation as an Indicator of Malignant Potential in Oral Lichen Planus: an Immunohistochemical Study

Background: Oral lichen planus (OLP) is categorized as premalignant lesion although its malignant potentialis a matter of controversy. The objective of this study was to investigate Ki67 expression in OLP, oral epithelialdysplasia and oral squamous cell carcinoma (OSCC). Materials and Methods: Expression of Ki67 was evaluatedthrough immunohistochemistry (IHC) in groups of A (17 cases of epithelial hyperplasia), B (16 cases of OLP), C1(10 cases of mild epithelial dysplasia), C2 (10 cases of severe epithelial dysplasia), D1 (10 cases of well-differentiatedOSCC), and D2 (10 cases of poorly-differentiated OSCC). Results: There was a significant difference in Ki67expression based on quantitative analysis among the six studied groups as well as group B compared bilaterallywith groups C2, D1 and D2 (p< 0.0001). However, there was no significant difference between groups B and C1or between groups D1 and D2 (p> 0.05). Conclusions: Based on the results of the present study it may not bepossible to definitely consider malignant transformation potential for OLP. However, expression of Ki67 wassignificantly higher in OLP than that of epithelial hyperplasia with no significant difference from that of mildepithelial dysplasia. This should be considered by clinicians to carefully and regularly follow up OLP lesions todetect potential subtle changes at an early stage.     

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.     

Increased Expression of the PRL-3 Gene in Human Oral Squamous Cell Carcinoma and Dysplasia Tissues

Phosphatase of regenerating liver (PRL) belongs to a class of the protein tyrosine phosphatase family, whichis known so far to consist of 3 members, PRL-1, PRL-2, and PRL-3. The aim of this study was to uncover therole of PRL genes in development of oral malignancy. We analyzed expression levels of the 3 PRL genes in 50human oral squamous cell carcinomas (OSCCs), 11 dysplasia and 12 normal mucosa tissues by a real-time RTPCRmethod. PRL-3 but not PRL-1 or PRL-2 expressions were significantly higher in OSCC and dysplasia thanin normal mucosa tissues. Additionally, PRL-3 expressions were significantly higher in OSCC tissues harboringdominant-negative p53 or recessive p53 mutation than in those harboring wild-type p53. These results suggestthat PRL-3 plays a role in oral cancer development and can be useful as a marker of pre-malignant and malignantlesion of oral mucosa.