MCM-2 expression differentiates potentially malignant verrucous lesions from oral carcinomas.

BACKGROUND: Mcm-2 is a biomarker belonging to Mcm family of proteins which has rarely been used in oral potentially malignant and malignant lesions of the verrucous type. The objective of this study is to assess the expression of Mcm-2 in Normal Oral Mucosa (NM), Verrucous Hyperplasia (VH), Verrucous Carcinoma (VC) and Oral Squamous Cell Carcinoma (OSCC) and compare it with the clinicopathological characteristics. METHODOLOGY: A total of 70 formalin fixed paraffin embedded tissue samples (10 cases of Normal Mucosa NM- Group A, 10 cases of Verrucous Hyperplasia- VH without Dysplasia- Group B, 10 cases of Verrucous Hyperplasia- VH with Dysplasia- Group C, 20 cases of Verrucous Carcinoma VC-Group D, 20 cases of Oral Squamous Cell Carcinoma OSCC- Group E) were subjected to immunohistochemistry with Mcm-2 antibody. Statistical analysis was carried out with various tests like ANOVA, Tukey HSD, Chi-Square and Shapiro-Wilk test by using the SPSS software. RESULTS: There was a significant difference in Mcm-2 expression with quantitative analysis among all the groups (p < 0.05). There was a significant progressive increase in nuclear Labelling Indices (nLI) from NM (49.08%), VC (60.45%), VH with Dysplasia (64.10%), and OSCC (89.22%). CONCLUSION: The findings suggest that Mcm-2 may be a sensitive proliferation marker in oral potentially malignant and malignant lesions which may be useful for differentiating between VH with/ without dysplasia, VC and OSCC.

Integrating Mcm-2 and Ki-67 immunohistochemistry with clinico-pathologic parameters for enhanced prognostic accuracy in oral verrucous lesions.

BACKGROUND: Oral verrucous lesions (OVLs) present a diagnostic challenge due to their diverse and often confusing histopathological features. Accurate differentiation is essential for improving diagnosis and predicting prognosis. In addition to assessing overall survival (OS) and disease-free survival (DFS) in verrucous squamous cell carcinoma (VSCC) and conventional OSCC, this study seeks to evaluate the expression of Mcm-2 and Ki-67 in verrucous lesions and oral squamous cell carcinoma (OSCC). These findings will be correlated with the nuclear expression of Mcm-2 and Ki-67. METHODOLOGY: Ninety tissue samples that were paraffin embedded and formalin-fixed were examined using immunohistochemistry to determine the expression of Mcm-2 and Ki-67. Data on survival and clinico-pathologic characteristics were taken from patient records. Statistical analyses were conducted using Independent T-tests, Cox regression models, and Kaplan-Meier survival analysis. RESULTS: Mcm-2 was identified as a more sensitive and prognostic marker compared to Ki-67 across the study groups. Mcm-2 overexpression was observed in all cases of verrucous hyperplasia with dysplasia, verrucous carcinoma (VC), VSCC, and conventional OSCC. The 3-year OS and DFS rates were lower in conventional OSCC (75 % and 64.3 %, respectively) compared to VSCC (90 % and 70 %). CONCLUSION: This study represents the first initiative to employ both Mcm-2 and Ki-67 as proliferative markers for distinguishing between various oral verrucous lesions. Mcm-2 proves to be a valuable marker for differentiating between potentially malignant and malignant verrucous lesions. However, further validation with larger sample sizes and longer follow-up periods is necessary to confirm its role in predicting OS and DFS.

Assessment of Proliferative Index Between the Tumor Margin, Center of Tumor, and the Invasive Tumor Front of Oral Squamous Cell Carcinoma With the Help of Mcm-2: An Immunohistochemical Study.

AIM: The knowledge of cellular proteins that involves cell cycle and its control system is essential for understanding tumor biology. Minichromosome maintenance protein (Mcm-2), a component of prereplicative complex, essential for initiating DNA replication, is deregulated in different malignant lesions, and is expressed throughout the whole cell cycle including the G0 and G1 phases. This characteristic cell cycle event is not found in other proliferative markers such as geminin, AgNOR, Ki-67, and proliferating cell nuclear antigen. The aim of the present study was to analyze and compare the expression of Mcm-2 in normal oral mucosa (NM) and oral squamous cell carcinomas at tumor margins (TM), the tumor center (TC), and the invasive tumor front (ITF), with correlation of clinicopathologic features. MATERIALS AND METHODS: Tissues from 50 oral squamous cell carcinomas and 10 NM were archived retrospectively and stained with an antibody directed against the Mcm-2 antigen. A quantitative method was used to score the Mcm-2 expression in NM, TM, TC, and ITF. Nuclei labeling index for each case was estimated as the percentage of immunoreactive nuclei among 500 cells separately for NM, TM, TC, and ITF. RESULTS: Nuclei labeling index increases progressively from NM (49.08%), TM (67.79%), and TC (76.87%) to ITF (87.77%). CONCLUSIONS: Cell proliferation by Mcm-2 at the ITF had a strong positive relationship with TC, TM. Mcm-2, a pan-cell cycle marker, is more sensitive in comparison with other conventional proliferative markers, which can be a better prognostic indicator.