Cellular origins of ultraviolet radiation-induced corneal tumours in the grey, short-tailed South American opossum (Monodelphis domestica).
Corneal tumours were induced in almost 100% of grey, short-tailed South American opossums (Monodelphis domestica) exposed three times weekly to ultraviolet radiation (UVR) for periods of a year or more. Five tumours, representing the morphological spectrum of UVR-induced corneal tumours (two fibrosarcomas, one malignant fibrous histiocytoma, one putative haemangiosarcoma, and one squamous cell carcinoma overlying a sarcoma), were assayed immunohistochemically for reactivity with antibodies against the intermediate filaments vimentin, smooth muscle actin (alpha isoform), muscle-specific actins (alpha and gamma isoforms), desmin and cytokeratin, and with antibodies against the vascular endothelial marker von Willebrand factor. The squamous cell carcinoma was cytokeratin-positive. Other tumours were cytokeratin-negative and vimentin-positive. Three tumours had scattered individual cells and groups of cells immunoreactive with antibodies against smooth muscle actin and muscle-specific actins; two tumours (a fibrosarcoma and the malignant fibrous histiocytoma) had small numbers of desmin-positive cells. The putative haemangiosarcoma contained two populations of neoplastic cells, von Willebrand factor-positive vascular endothelial cells and smooth muscle actin-positive spindle cells. It was concluded (1) that UVR-induced corneal tumours may be composed of cells derived from resident epithelial cells, immigrant vascular endothelial cells, or fibroblast-like cells of unknown origin, and (2) that such tumours may contain more than one neoplastic cell type.
Kusewitt
D F
DF
Department of Cell Biology and Physiology, University of New Mexico, Albuquerque, NM 87131-5218, USA.
Hubbard
G B
GB
Warbritton
A R
AR
McLeskey
S W
SW
Miska
K B
KB
Henkel
R D
RD
Robinson
E S
ES
D000199:Actins / Q000032:analysis; D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D003315:Cornea / Q000737:chemistry / Q000473:pathology / Q000528:radiation effects*; D003893:Desmin / Q000032:analysis; D005134:Eye Neoplasms / Q000209:etiology / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005354:Fibrosarcoma / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D006394:Hemangiosarcoma / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D018219:Histiocytoma, Benign Fibrous / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D008297:Male; D009130:Muscle, Smooth / Q000737:chemistry; D009893:Opossums; D011833:Radiation Injuries, Experimental / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D014466:Ultraviolet Rays / Q000009:adverse effects*; D014746:Vimentin / Q000032:analysis; D014841:von Willebrand Factor / Q000032:analysis
D000199:Actins; D003893:Desmin; D014746:Vimentin; D014841:von Willebrand Factor; D007633:Keratins