title: Comparison of oncostatin M expression in keratoacanthoma and squamous cell carcinoma.
abstract: Oncostatin M (OSM) is a 28-kDa glycoprotein, produced by stimulated macrophages and T lymphocytes, that inhibits the proliferation and induces differentiation of a number of different cell lines derived from solid tumors. To determine whether keratoacanthoma (KA) is unique or a variant of squamous cell carcinoma (SCC), we compared the immunohistochemical expression of OSM in the tumor cells and peri- and intratumoral macrophages of 21 mature KAs, 7 regressing KAs, and 27 SCCs. An inverse correlation was identified between OSM tumor labeling and the density of OSM-labeled tumor-associated macrophages for KAs (r = -.4; P = .09). OSM tumor expression was significantly more frequent and more intense in KAs than in SCCs (95% versus 63%; P < .01). In contrast, the density of OSM-labeled macrophages was significantly higher in SCCs compared with mature KAs (7/3 high power fields versus 4/3 high power fields; P = .02). These OSM-positive macrophages were predominantly located at the advancing, infiltrative margins of both neoplasms. Regressing KAs demonstrated a decreased level of OSM tumor expression compared with mature KAs (53% versus 95%; P = .001), but there was no difference in density of OSM-labeled macrophages. Both the above differences and the overlapping patterns of OSM expression suggest that KAs are a variant of SCC where OSM, possibly as an autocrine factor, may mediate KA's overwhelming but not absolute tendency to involute.
authors.affiliation: Department of Pathology and Laboratory Medicine, Albany Medical College, New York 12208, USA.
authors.forename: T A
authors.initials: TA
authors.lastname: Tran
authors.forename: J S
authors.initials: JS
authors.lastname: Ross
authors.forename: C E
authors.initials: CE
authors.lastname: Sheehan
authors.forename: J A
authors.initials: JA
authors.lastname: Carlson
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000378:metabolism* / Q000473:pathology; D003593:Cytoplasm / Q000737:chemistry; D006801:Humans; D007150:Immunohistochemistry; D007636:Keratoacanthoma / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000737:chemistry; D053683:Oncostatin M; D010455:Peptides / Q000032:analysis*; D012878:Skin Neoplasms / Q000378:metabolism* / Q000473:pathology
chemical_list: C508351:OSM protein, human; D010455:Peptides; D053683:Oncostatin M