Expression of gamma glutamyl hydrolase and carbonic anhydrase 9 in oral squamous cell carcinoma and their association with extracapsular spread

Introduction: Extracapsular spread (ECS) is one of the most important prognostic factors in oral squamous cell carcinoma (OSCC). Gamma Glutamyl Hydrolase (GGH) is a lysosomal enzyme which is involved in folate homeostasis. It is overexpressed in several human malignancies but its role in OSCC has never been reported. Carbonic Anhydrase 9 (CA9) is a transmembrane glycoprotein and is related to hypoxia. High expression of CA9 has been associated with poor prognosis in several tumours including OSCC. This study was aimed to investigate the expression of GGH and CA9 in OSCC and their potential use as biomarkers to predict ECS. Materials and Methods: Immunohistochemical staining with GGH and CA9 markers were performed in 35 cases of OSCC (19 with ECS and 16 without ECS) and 5 cases of normal mucosa. A semi-quantative index was used for immunoscoring. Association between the expression of these markers and ECS status were analyzed using chi-square test. Results: Immunohistochemical results indicated that GGH and CA9 were upregulated in OSCC. High GGH and CA9 expression were significantly associated with ECS (p<0.05). Combination of GGH and CA9 showed greater prognostic accuracy as compared to the individual markers. Conclusion(s): Both separately and in combination GGH and CA9 offer potential as prognostic biomarkers in OSCC and was thus reliable in segregating the OSCC cases based on ECS status

Transcriptional analysis highlights three distinct immune profiles of high-risk oral epithelial dysplasia

Oral potentially malignant disorders (OPMD) are precursors of oral squamous cell carcinoma (OSCC), and the presence of oral epithelial dysplasia (OED) in OPMD confers an increased risk of malignant transformation. Emerging evidence has indicated a role for the immune system in OPMD disease progression; however, the underlying immune mechanisms remain elusive. In this study, we used immune signatures established from cancer to delineate the immune profiles of moderate and severe OED, which are considered high-risk OPMD. We demonstrated that moderate and severe OEDs exhibit high lymphocyte infiltration and upregulation of genes involved in both immune surveillance (major histocompatibility complex-I, T cells, B cells and cytolytic activity) and immune suppression (immune checkpoints, T regulatory cells, and tumor-associated macrophages). Notably, we identified three distinct subtypes of moderate and severe OED: immune cytotoxic, non-cytotoxic and non-immune reactive. Active immune surveillance is present in the immune cytotoxic subtype, whereas the non-cytotoxic subtype lacks CD8 immune cytotoxic response. The non-immune reactive subtype showed upregulation of genes involved in the stromal microenvironment and cell cycle. The lack of T cell infiltration and activation in the non-immune reactive subtype is due to the dysregulation of CTNNB1, PTEN and JAK2. This work suggests that moderate and severe OED that harbor the non-cytotoxic or non-immune reactive subtype are likely to progress to cancer. Overall, we showed that distinct immune responses are present in high-risk OPMD, and revealed targetable pathways that could lead to potential new approaches for non-surgical management of OED

Overexpression of MMP13

Matrix metalloproteinase 13 (MMP13) plays a central role in the MMP activation cascade that enables degradation of the extracellular matrix and basement membranes, and it is identified as a potential driver in oral carcinogenesis. Therefore, this study aims to determine the copy number, mRNA, and protein expression of MMP13 in oral squamous cell carcinoma (OSCC) and to associate these expressions with clinicopathological parameters. Copy number, mRNA, and protein expression analysis of MMP13 were determined using real-time quantitative PCR and immunohistochemistry methods in OSCC samples. The correlations between MMP13 expressions and clinicopathological parameters were evaluated, and the significance of MMP13 as a prognostic factor was determined. Despite discrepancies between gene amplification and mRNA and protein overexpression rates, OSCC cases showed high amplification of MMP13 and overexpression of MMP13 at both mRNA and protein levels. High level of MMP13 protein expression showed a significant correlation with lymph node metastasis (P=0.011) and tumor staging (P=0.002). Multivariate Cox regression model analysis revealed that high level of mRNA and protein expression of MMP13 were significantly associated with poor prognosis (P<0.050). Taken together, these observations indicate that the MMP13 protein overexpression could be considered as a prognostic marker of OSCC

Expression of gamma glutamyl hydrolase and carbonic anhydrase 9 in oral squamous cell carcinoma and their association with extracapsular spread

Introduction: Extracapsular spread (ECS) is one of the most important prognostic factors in oral squamous cell carcinoma (OSCC). Gamma Glutamyl Hydrolase (GGH) is a lysosomal enzyme which is involved in folate homeostasis. It is overexpressed in several human malignancies but its role in OSCC has never been reported. Carbonic Anhydrase 9 (CA9) is a transmembrane glycoprotein and is related to hypoxia. High expression of CA9 has been associated with poor prognosis in several tumours including OSCC. This study was aimed to investigate the expression of GGH and CA9 in OSCC and their potential use as biomarkers to predict ECS. Materials and Methods: Immunohistochemical staining with GGH and CA9 markers were performed in 35 cases of OSCC (19 with ECS and 16 without ECS) and 5 cases of normal mucosa. A semi-quantative index was used for immunoscoring. Association between the expression of these markers and ECS status were analyzed using chi-square test. Results: Immunohistochemical results indicated that GGH and CA9 were upregulated in OSCC. High GGH and CA9 expression were significantly associated with ECS (p<0.05). Combination of GGH and CA9 showed greater prognostic accuracy as compared to the individual markers. Conclusion(s): Both separately and in combination GGH and CA9 offer potential as prognostic biomarkers in OSCC and was thus reliable in segregating the OSCC cases based on ECS status

Extracapsular spread in oral squamous cell carcinoma and its association with GGH, CDKN3 and CBX7

PURPOSE OF STUDY: Extracapsular spread (ECS) in oral squamous cell carcinoma (OSCC) indicates tumour aggressiveness and is associated with a higher risk for tumour recurrence, loco-regional spread and distant metastasis. The identification of specific biomarkers that could predict ECS would guide the clinicians in the management of OSCC patients. This study aimed to determine the association between clinical and pathological parameters of OSCC patients with ECS. We also sought to investigate the expression of Gamma Glutamyl Hydrolase (GGH), Cyclin Dependent Kinase Inhibitor 3 (CDKN3) and Chromobox Homolog 7(CBX7) and their potential use as biomarkers to predict ECS in OSCC. MATERIALS AND METHODS: Association between clinicopathological parameters and expression of these markers with ECS status was analysed using chi-square test. Immunohistochemical staining with anti-GGH, anti-CDKN3 and anti-CBX7 antibodies was performed on 35 OSCC cases. RESULTS: The number of positive nodes and the highest anatomical level of nodal involvement significantly correlated with ECS (p<0.05). Immunohistochemical staining results indicated that high GGH expression was significantly associated with ECS (p<0.05), while no significant association was seen for CDKN3 and CBX7 expression with ECS. However, a trend towards significance was observed with a high level of CDKN3 and low level of CBX7 expression with ECS. CONCLUSIONS: The presence of ECS is a predictor for the pathological involvement of greater number of nodes from a higher anatomical level. GGH offers potential as a prognostic biomarker in OSCC, while the role of CDKN3 and CBX7 as prognostic markers need to be validated in a larger sample

Verrucous Papillary Lesions: Dilemmas in Diagnosis and Terminology

Verrucous papillary lesions (VPLs) of oral cavity are diagnostically challenging as they include a spectrum of benign, potentially malignant, and frankly malignant lesions. A majority of the benign VPLs have viral aetiology and include commonly occurring squamous papilloma along with verruca vulgaris, focal epithelial hyperplasia, and condyloma. Current understanding of potentially malignant VPLs is perplexing and is primarily attributed to the use of confusing and unsatisfactory terminology. Clinically and histologically oral verrucous hyperplasia, a potentially malignant disorder, resembles oral verrucous carcinoma and may be indistinguishable from one another. The most reliable way to separate these entities on routine haematoxylin-eosin stained tissue sections is to recognize the exophytic growth patterns of oral verrucous hyperplasia from the combined exophytic and endophytic growth patterns associated with verrucous carcinoma. A review of the literature showed that there is a lot of confusion regarding the current clinical and histopathological guidelines to diagnose this potentially malignant entity. The criteria elaborated by different authors in establishing the diagnosis of oral verrucous hyperplasia are discussed in detail. A brief overview of the treatment modalities adopted is also discussed. The need for establishing a clear understanding of this potentially malignant entity is stressed as it may have far reaching implications on its management