MLH1, MSH2, MRE11, and XRCC1 in Oral Leukoplakia and Oral Squamous Cell Carcinoma.

BACKGROUND: DNA damage is accumulated in the cells over time as the result of both exogenous and endogenous factors. The objective of this study was to analyze the immunohistochemical expression of the repair proteins in oral leukoplakia (OL) and oral squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Paraffin blocks were selected from the archives of the Laboratory of Hospital Clinico Universitario de Santiago de Compostela, Spain. The sample was composed of 16 cases of OL without dysplasia, 14 cases of OL with dysplasia, and 15 cases of OSCC. The patients' clinical data were collected and immunohistochemical analysis was performed for MLH1, MSH2, MRE11, and XRCC1. The data were submitted to the χ2 and the Kruskal-Wallis (P≤0.05) tests. RESULTS: MSH2 was overexpressed in OSCC (P=0.020) and was positive in 100% of patients with OL with dysplasia or OSCC (P=0.019). Positivity for MLH1 was significantly associated with comorbidity (P=0.040), especially in patients who presented with 2 or more pathologies (P=0.028). XRCC1 positivity was also associated with comorbidity (P=0.039). No significant associations were found for the MRE11A expression. Although the simultaneous positivity for the 4 markers was observed in presence of comorbidities (P=0.006). CONCLUSIONS: This study supports the effect of the overexpression of MSH2 protein in samples of OL with dysplasia and OSCC, most notably in patients who present with comorbidities and negativity for OL without dysplasia.

Gingival exophytic lesions as first oral manifestation of primary lung adenocarcinomas: Systematic review.

Metastases from malignant tumors in the oral cavity are rare and comprise approximately 1% of all oral neoplasms, being more frequent in the jaws than in the soft tissues. The presentation of a gingival metastasis as the first manifestation of a primary tumor in the oral cavity is extremely rare. The objective of this review is to update the diagnosis and management of oral metastasis being the first clinical manifestation of the tumor and review all the cases published to date, providing a new original clinical case with very specific histopathological characteristics. We systematically reviewed the literature in order to find all the cases of primary lung tumors that appeared with a gingival metastasis as the first manifestation. The search process involved a total of 1916 articles. After reading the latter, 15 (one of them with two different cases) met the inclusion criteria. Of the 15 articles, 6 were rated as medium quality (40%) and 9 as high quality (60%). We present a lung adenocarcinoma that first manifested as a metastasis in the gum, simulating a benign lesion. The unusually high growth rate of this lesion should conduct to have other diagnostic possibilities, and histopathological confirmation is essential.

Aortic Valve Replacement In Alkaptonuric Ochronosis.

Alkaptonuria is an autosomal recessive inborn error of metabolism of the aromatic amino acids. Deficiency of the homogentisate1,2-dioxygenase leads to an increased blood and urinary concentration of homogentisc acid resulting in a slow accumulation of its oxidation products in the connective tissues (ochronosis). The most common clinical manifestation of ochronosis is arthropathy whereas cardiac involvement is very infrequent. We report the case of a patient with ochronotic involvement of the aortic valve who underwent a valve replacement. Some aspects of pathogenesis, and treatment are discussed.

Integrative analysis of gene alterations and immunoexpression profiles of cell cycle checkpoints in oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) represents 95% of all cancers of the head and neck region. The five-year survival rate of OSCC patients is about 60% and has not gone throw significant improvements despite recent advances in molecular biology, or the identification of key pathways in its pathophysiology such as cell cycle. OBJECTIVE: 1) to analyse the inmunoexpression of cell cycle checkpoints (CPs) in an OSCC institutional cohort and to relate it to clinicopathological features and survival, and 2) to study CPs-related genes in the OSCC subset of the TCGA database. METHODS: Immunohistochemistry (IHC) for p16INK4a, p21CIP1, cyclin D1 and p27KIP1 protein expression was quantified by tissue microarray analysis in 68 samples from OSCC patients. In order to analyse its correlation with genetic information, a cohort belonging to The Cancer Genome Atlas (TCGA) database was analysed. RESULTS: Of 68 patients, 34 (50%) developed recurrence, and 36 (52.09%) died as a result of disease progression (mean survival 34.09 months). IHC staining for nuclear cyclin D1 was associated with worse staging and tobacco use. p16INK4a, p21CIP1, cyclin D1, and p27KIP1 expression was unrelated to overall survival. No statistically significant correlation linked the CPs-related genes mutations to OSCC overall survival in the TCGA database. CONCLUSIONS: CPs variations at a phenotype and genotype level seem not to affect significantly clinicopathological features and survival in the studied OSCC cohorts.