Role of plasminogen activator inhibitor-1 in oral tongue squamous cell carcinoma: An immunohistochemical and in vitro analysis.

OBJECTIVE: To evaluate the influence of plasminogen activator inhibitor-1 (PAI-1) on the biological behavior and prognosis of oral tongue squamous cell carcinoma (OTSCC). METHODS: Immunoexpression of PAI-1 was analyzed in 60 OTSCC specimens and classified as low-expression (≤50% of positive cells) or high-expression (>50%). In vitro effects of recombinant human PAI-1 (rhPAI-1) were assessed through functional assays on the OTSCC-derived cell line SCC-25. Three cell groups were evaluated: G0 (control), G10 (10 nM rhPAI-1), and G20 (20 nM rhPAI-1). RESULTS: High membrane expression of PAI-1 was associated with tumor budding (p = 0.046) and high-risk cases (p = 0.043). Cytoplasmic and membrane expression of PAI-1 was not associated with patient survival. Cell viability (p = 0.020) and progression to the S-phase of the cell cycle (p = 0.024) were higher in G10 and G20 at 24 h. The percentages of apoptotic/necrotic cells were not affected by rhPAI-1. The presence of rhPAI-1 increased cell migration (p = 0.039) and invasion (p = 0.039) after 24 and 72 h, respectively. CONCLUSION: Our findings indicate the involvement of PAI-1 in the biological behavior of OTSCC, although its expression may not predict patient survival. The in vitro results suggest that PAI-1 stimulates cell proliferation, migration and invasion and may contribute to the aggressive phenotype of OTSCC.

Relationship between mast cells and E-cadherin in odontogenic keratocysts and radicular cysts.

OBJECTIVE: This study aimed to evaluate tryptase and E-cadherin protein expression in odontogenic keratocysts (OKCs) and radicular cysts (RCs) and their relationship with lesion size. MATERIALS AND METHODS: Thirty OKC and 30 RC cases were analyzed by immunohistochemistry. Tryptase expression was quantitatively assessed using the quantification of mast cells, and expression of E-cadherin was semi-quantitatively analyzed estimating the proportion of positive cells: 1 = less than 25% of immunopositive cells; 2 = 26 to 50% of immunopositive cells; 3 = 51 to 75% of immunopositive cells; 4 = more than 75% of immunopositive cells. Data on cystic lesion sizes were obtained from patients' clinical files, based on previous radiographic exams, and the lesions were categorized into three groups: group 1 (< 2 to 2 cm); group 2 (> 2 to 4 cm), and group 3 (> 4 cm). RESULTS: Higher mast cell means were found for RCs, with the predominance of degranulated mast cells in both OKCs and RCs (p = 0.082). Concerning the epithelial component, a higher concentration of degranulated mast cells was detected in RCs (p = 0.000). Regarding connective tissue, degranulated mast cells were more evident in OKCs (p = 0.762). A negative correlation was observed between E-cadherin expression and total number of mast cells (p = 0.011), degranulated mast cells (p = 0.040), and degranulated mast cells in both superficial (p = 0.035) and deep connective tissues (p = 0.009). Concerning lesion size, a negative correlation with total number of mast cells (p = 0.016) and number of degranulated mast cells (p = 0.049) was observed, both in the epithelial components. Herein, the larger the lesion size, the lower the number of degranulated mast cells in the epithelium (r = - 0.271; p = 0.49), suggesting that these cells play a role in the initial cystic expansion phase. CONCLUSION: The higher expression of tryptase in degranulated mast cells was linked to a lower expression of E-cadherin, which may be related to a change in the epithelial permeability in these lesions, contributing to increased cystic content and lesion growth. CLINICAL RELEVANCE: Evidence of the relationship between mast cells and E-cadherin in the growth of odontogenic cysts was studied.

Immunoexpression of claudin-1 and Nm23-H1 in metastatic and nonmetastatic lower lip squamous-cell carcinoma.

The aim of this study was to evaluate the immunoexpression of claudin-1 and Nm23-H1 in metastatic and nonmetastatic lower lip squamous-cell carcinoma (LLSCC). Twenty LLSCCs with regional nodal metastasis and 20 LLSCCs without metastases were selected. The percentage of claudin-1 staining and the staining intensity and percentage of Nm23-H1 staining in each tumor core were assessed. Metastatic tumors exhibited higher expression of claudin-1 than nonmetastatic tumors (P = 0.030). Similarly, stage III and IV LLSCCs showed higher expression of claudin-1 than stages I and II (P = 0.026). The percentage of claudin-1 staining was scored as 2 in most well-differentiated and moderately differentiated tumors, whereas poorly differentiated tumors showed a relatively similar distribution of scores 2, 1, and 0 (P = 0.648). Regarding Nm23-H1, there was a predominance of negative cases for both metastatic and nonmetastatic tumors (P = 0.235). In addition, no significant differences in the percentage of Nm23-H1-negative and Nm23-H1-positive cases were observed regarding the clinical staging (P = 0.430) and the histologic grading of malignancy (P = 0.702). The results of this study suggest an important role of claudin-1 in the development of metastasis in LLSCCs. In contrast, the present findings do not support a significant role of Nm23-H1 in metastasis suppression of LLSCC.

Intraoral molluscum contagiosum in a young immunocompetent patient.

Molluscum contagiosum (MC) is a contagious disease caused by a virus of the poxvirus family. In children, the disease commonly manifests as a variable number of discrete umbilicated papules on the face and trunk. In healthy and immunosuppressed adults, the disease appears on or near the genital organs and is often sexually transmitted. MC involving the intraoral mucosa has been documented but is rare. We report a case of MC involving the oral mucosa exclusively and discuss the main clinical, histopathologic, and therapeutic characteristics, comparing the findings with cases of this rare oral presentation described in the literature.