Fine structural studies of induced tumors arising within the prostatic complex of Lobund-Wistar rats

• Published in: The Prostate Vol. 32; no. 3; pp. 173 - 178
• Main Authors: Heidger Jr, Paul M., Lubaroff, David M., Cohen, Michael B.
• Format: Journal Article
• Language: English
• Published: New York Wiley Subscription Services, Inc., A Wiley Company 01.08.1997; Wiley-Liss
• Subjects: adenocarcinoma; Adenocarcinoma - pathology; Adenocarcinoma - ultrastructure; Animals; Biological and medical sciences; Cell Nucleus - ultrastructure; Connective Tissue - ultrastructure; electron microscopy; Epithelium - pathology; Epithelium - ultrastructure; inducible tumor; Male; Medical sciences; Microscopy, Electron; Nephrology. Urinary tract diseases; Organelles - ultrastructure; Prostate - pathology; Prostate - ultrastructure; prostate gland; Prostatic Neoplasms - pathology; Prostatic Neoplasms - ultrastructure; Rats; Rats, Wistar; Tumors of the urinary system; Urinary tract. Prostate gland; Adenocarcinoma; Animal model; Urinary system disease; Prostate disease; Androgen; Rat; Induction; Cytologic investigation; Rodentia; Malignant tumor; Experimental study; Electron microscopy; Pathology; Vertebrata; Mammalia; Association; Animal; Male genital diseases; Prostate
• ISSN: 0270-4137; 1097-0045
• DOI: 10.1002/(SICI)1097-0045(19970801)32:3<173::AID-PROS3>3.0.CO;2-M

BACKGROUND Morris Pollard, Phyllis Luckert, and colleagues have reported the occurrence of spontaneously arising tumors of the prostatic complex in aged Lobund‐Wistar (L‐W) rats, and have also shown that the genesis of such tumors may be accelerated by means of intravenous administration of methylnitrosourea, followed by androgen supplementation. METHODS Light and electron microscopic investigations of the tumors arising under this regime were conducted, with the objective of documenting morphological changes attending the transformation process; 10 tumor samples were used for the electron microscopic studies. RESULTS All tumors studied were adenocarcinomas arising within the prostatic complex of induced animals. These tumors varied in size, degree of differentiation, and invasiveness. Foci of prostatic intraepithelial neoplasia were noted in light microscopic studies as well. Consistent fine structural features exhibited by cells of the induced adenocarcinomas included a large nuclear to cytoplasmic ratio; large irregular nuclei with heavily marginated chromatin; conspicuous nucleoli; abundant ribosomes and polysomes and a paucity of rough endoplasmic reticulum; and numerous cytoplasmic vesicles and lipid inclusions. Numerous, short microvilli extended from the cell surface into a copious surrounding extracellular matrix. CONCLUSIONS Thus, these tumors shared many of the fine structural features characteristic of the Dunning (rat) and human prostatic adenocarcinomas. Prostate 32:173–178, 1997. © 1997 Wiley‐Liss, Inc.