Metabolic Heterogeneity Confers Differences in the Tumor Microenvironment of Aggressive Types of Melanomas.

Background: Melanoma affects skin and mucosa and can be particularly aggressive when the lesion is an advanced cutaneous tumor or located in the sinonasal or oral mucosa. Reprogramming of energy metabolism has been defined as a hallmark of cancer; so this study aimed to verify the expression of proteins related to metabolism and cellular proliferation.

Methods: Immunohistochemical analysis with antibodies adipophilin, FASN, GLUT-1, HIF-1α, and Ki-67 was performed in a series of 28 sinonasal melanomas (SM), 16 oral melanomas (OM), and 39 cutaneous melanomas (CM).

Lysozyme Expression Can be Useful to Distinguish Mammary Analog Secretory Carcinoma from Acinic Cell Carcinoma of Salivary Glands.

Lysozyme is an enzymatic marker of acinar and intercalated duct cells of normal salivary glands. The aim of this study was to verify whether lysozyme expression could be useful to distinguish acinic cell carcinoma (ACC) from its main mimic, mammary analog secretory carcinoma (MASC). For comparison, DOG1 expression was analyzed as well.

Loss of expression of Plag1 in malignant transformation from pleomorphic adenoma to carcinoma ex pleomorphic adenoma.

PLAG1 (pleomorphic adenoma gene 1) is frequently activated in pleomorphic adenoma (PA). Carcinoma ex pleomorphic adenoma (CXPA) arises in PA, and PLAG1 expression is believed to be maintained from PA to CXPA, as it can contribute to the carcinogenesis process. To evaluate if PLAG1 is a good marker of malignant transformation from PA to CXPA as well as to evaluate if PLAG1 expression is associated with progression and histopathologic subtype of CXPA.

Immunohistochemical expression of cyclooxygenase-2 (COX-2) in oral nevi and melanoma.

Background: Cyclooxygenase-2 (COX-2) catalyses the conversion of arachidonic acid to prostaglandin, and its overexpression has been demonstrated in different malignant tumors, including cutaneous melanoma. However, no data about the expression of this protein in oral melanocytic lesions are available to date. The aim of this study was to evaluate the immunohistochemical expression of COX-2 in oral nevi and melanomas, comparing the results with correspondent cutaneous lesions.