Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027960 (mole)
 21,279 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Claudins are a family of transmembrane proteins involved in cell-to-cell adhesion and are believed to be the main component of tight junctions. Recent studies have suggested that some metastatic solid tumors lack claudin expression. It is unknown whether claudins play a role in cutaneous melanoma. Immunohistochemical studies were performed on tissue microarrays containing 19 benign melanocytic nevi (BN), 21 dysplastic nevi (DN), 23 primary malignant melanomas (MMs), and 31 metastatic melanomas (MMMs) using a polyclonal anti-claudin-1 antibody. Immunoreactivity in tumor cells and associated vessels was graded by intensity and by percentage of reactive cells. Normal epidermis served as internal control (3+ labeling). Cases with at least 2+ labeling in more than 25% of the cells were considered positive. Claudin-1 expression was present in 37% of BN, 24% of DN, 26% of MM, and 3.2% of MMM. Tumor-associated vessels showed the following results: 11 of 19 (58%) in BN, 14 of 21 (67%) in DN, 17 of 23 (74%) in MM, and 6 of 31 (19%) in MMM. A significant loss of expression was noted between MMM and all other lesions in tumor cells and associated vessels. There was no significant difference between BN, DN, and MM. Within primary melanomas, there was a significant correlation between expression of claudin in tumor cells and Clark level/Breslow thickness. Also significant was a decreased expression of claudin in tumor vessels of lesions with higher Breslow thickness or Clark level. These data suggest that loss of claudin-1 may play a significant role in the acquisition of metastatic phenotype in cutaneous melanoma. Cohn ML, Goncharuk VN, Diwan AH, Zhang PS, Shen SS, Prieto VG. Loss of claudin-1 expression in tumor-associated vessels correlates with acquisition of metastatic phenotype in melanocytic neoplasms.
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PMID:Loss of claudin-1 expression in tumor-associated vessels correlates with acquisition of metastatic phenotype in melanocytic neoplasms. 1611 50

Granular cell tumors (GCT) are nerve sheath neoplasms composed of Schwann cells with granular cytoplasm. Perineurial cells are the cellular component of the perineurium and of perineuriomas, neoplasms supposedly derived from perineurial cells. However, perineurial cells have also been found in other Schwann cell-derived tumors. These cells have not been well studied in GCTs. We studied the presence of perineurial cells in a series of 24 GCTs with EMA, claudin-1, and Glut-1, which are immunohistochemical markers for perineurial cells. Three cases lacked nerve fascicles. Three cases showed no perineurial proliferation (grade 0), 7 showed grade 1 proliferation, and 11 showed grade 2 proliferation. For comparison, we studied 17 cases of neoplasms with perineural invasion (PNI): 7 cutaneous neoplasms [squamous cell carcinomas (n = 3), cutaneous lymphoma, malignant melanoma, eccrine carcinoma, congenital neurotropic nevus (n = 1 each)] and 10 noncutaneous tumors [prostatic (n = 2), gastric (n = 2), and colonic (n = 2) adenocarcinomas; invasive ductal carcinoma of breast (n = 2); urothelial carcinoma of bladder (n = 1); and oral squamous cell carcinoma (n = 1)] with the same antibodies for perineurial cells. We found perineurial cell proliferation in 10 cases, 6 grade 1, and 4 grade 2. These perineurial cells were limited to the areas around the nerve fascicles. Most of the tumor was devoid of perineurial cells. Thus, it was interpreted more as a hyperplastic or reactive phenomenon than a neoplastic component. Claudin-1 was the most sensitive of the 3 markers that we used. Such proliferation was less intense in non-GCTs. In conclusion, proliferation of perineurial cells in GCTs and neoplasms with PNI is a common finding that had not been previously studied. It seems to be a non-neoplastic phenomenon.
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PMID:Perineurial cells in granular cell tumors and neoplasms with perineural invasion: an immunohistochemical study. 2266 77