Dual roles of E-cadherin in prostate cancer invasion.

The role(s) of E-cadherin in tumor progression, invasion, and metastasis remains somewhat enigmatic. In order to investigate various aspects of E-cadherin biological activity, particularly in prostate cancer progression, our laboratory cloned unique subpopulations of the heterogeneous DU145 human prostatic carcinoma cell line and characterized their distinct biological functions. The data revealed that the highly invasive, fibroblastic-like subpopulation of DU145 cells (designated DU145-F) expressed less than 0.

Innovative testing method for an integrated radiology-histology curriculum.

A module of radiology instruction was incorporated into an existing histology course for first-year medical students (n = 177). An innovative testing methodology for assessing the instructional effectiveness of the integrated radiology-histology module was developed and tested. Test items were designed to measure the students' ability to integrate the two disciplines successfully.

Integrated approach to teaching and testing in histology with real and virtual imaging.

The University of Iowa College of Medicine histology teaching laboratory incorporates extensive Web- and computer-based teaching modalities, including the Virtual Microscope (VM), as emerging learning aids in histology and pathology laboratory instruction. We report here our experience in offering a multiple resource-based approach to laboratory instruction while retaining the opportunity and requirement of examining actual microscopic slide preparations with the microscope. Acceptance of this approach has been high among our students and faculty, and performance levels established over years of teaching histology by traditional means have been maintained.

Prostatic tumor cell plasticity involves cooperative interactions of distinct phenotypic subpopulations: role in vasculogenic mimicry.

Background: Tumor cell plasticity represents a significant clinical challenge in that the fate and function of tumor cells can be elusive until a tumor mass is evident. A remarkable example of plasticity is tumor cell vasculogenic mimicry, recently described in aggressive uveal and cutaneous melanoma, in addition to ovarian carcinoma, whereby tumor cells express endothelial-associated genes and form de novo vasculogenic-like networks in three-dimensional (3-D) culture. In the current investigation, we examined whether there is evidence for vasculogenic mimicry in heterogeneous prostatic neoplasms.

Molecular determinants of ovarian cancer plasticity.

During development, the formation and remodeling of primary vascular networks occurs by vasculogenesis and angiogenesis. Recently, the term "vasculogenic mimicry" has been used by our laboratory and collaborators to reflect the embryonic-like ability of aggressive, but not nonaggressive, melanoma tumor cells to form a pattern of matrix-rich networks (containing channels) surrounding spheroids of tumor cells in three-dimensional culture, concomitant with their expression of vascular cell markers. Ovarian cancer is usually diagnosed as advanced stage disease in most patients when widespread metastases have already been established within the peritoneal cavity.

Comparison of a virtual microscope laboratory to a regular microscope laboratory for teaching histology.

Emerging technology now exists to digitize a gigabyte of information from a glass slide, save it in a highly compressed file format, and deliver it over the web. By accessing these images with a standard web browser and viewer plug-in, a computer can emulate a real microscope and glass slide. Using this new technology, the immediate aims of our project were to digitize the glass slides from urinary tract, male genital, and endocrine units and implement them in the Spring 2000 Histology course at the University of Iowa, and to carry out a formative evaluation of the virtual slides of these three units in a side-by-side comparison with the regular microscope laboratory.

A novel immunological model for the study of prostate cancer.

The Dunning R-3327 rat prostatic adenocarcinoma is a widely accepted model for in vivo experimental studies of prostate cancer. We have previously derived phenotypically distinct cell lines from a s.c.

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

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.

Heterogeneous Expression of Invasive and Metastatic Properties in a Prostate Tumor Model.

Cellular heterogeneity of neoplasia is well demonstrated in the Dunning R-3327 rat prostate adenocarcinoma. In this study, we measured the differential expression of invasive and metastatic properties of this prostate model by cloning from a heterogeneous parental cell line. Four cell clones were derived and characterized by morphological studies, E-cadherin expression, and invasive and metastatic potential.

Gross and microscopic pathology of induced prostatic complex tumors arising in Lobund-Wistar rats.

The necessity for additional animal models for prostate cancer has recently been stressed. The Pollard model of chemically induced prostate cancer has received attention in this regard although the histiogenetic origin of these tumors has come under question. We independently studied this model for the development of tumors in the prostate region.

Peptidergic nerves in the ureter.

Vasoactive intestinal peptide (VIP) and substance P were demonstrated in the pig ureter by immunohistochemical techniques. Nerves containing these materials were related mainly to the smooth muscle layer in the normal and obstructed ureter. In isolated ureteral segments, VIP caused relaxation at doses exceeding 0.

Cell wall deficient bacteria as a cause of idiopathic hematuria.

Idiopathic hematuria in the absence of bacteriuria is a medical challenge. Routine cultures of catheterized bladder and endoscopically obtained ureteral urine specimens from a 22-year-old woman with a 6-week history of hematuria showed no growth after 24 to 48 hours of incubation. However, bacterial variants were grown on enriched media.

Human doubled renal and testicular arteries.

Doubled renal and testicular arteries were found in a well-developed 69-year-old caucasian male. The right kidney had two renal arteries, one at its usual midorgan (hilar) position and one inferior polar. One testicular artery arose from the mid-point of the usual renal artery, passed under the renal vein at its junction with the inferior vena cava, and then crossed over the inferior polar renal artery.

Stereological study of Leydig cell density in the guinea pig testis.

Stereological analysis of Leydig cell and macrophage volume density along the long axis of the guinea pig testis was assessed quantitatively by histometric point counting. Morphological identification of Leydig cells was accomplished by staining for 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD), whereas macrophages were identified by vital staining (trypan blue). The average percentage of Leydig cell density constitutes about 10.

Immunocytochemical localization of metallothionein in the rat prostate gland.

Metallothionein (MT), which binds zinc and other metals, was localized within the rat prostatic complex at light and electron microscopic levels utilizing immunocytochemistry. Two groups of mature, male Sprague-Dawley rats were injected with cadmium chloride subcutaneously (2 mg/kg body weight) to induce the synthesis of MT, and were sacrificed 48 h postinjection. From the first group, prostatic tissue from the three lobes was prepared for light microscopy.

Characterization of the heterogeneity of R3327 rat prostatic tumors derived from single-cell clones.

Prostatic adenocarcinoma is characterized by cellular diversity, which is well demonstrated in the Dunning R3327 rat prostatic adenocarcinoma. This heterogeneity may arise from epigenetic influences, ie, cellular adaptation or selection, and/or from genetic changes. To investigate the question of genetic instability, four tissue culture cell lines were derived from single cells isolated from the uncloned late (UCL) passage of the Dunning R3327H prostate cell culture.

Androgen receptor binding characteristics in the cytosol of the rat dorsolateral prostate gland and the Dunning R-3327 prostatic adenocarcinoma.

The incidence of prostatic cancer is highly correlated with advanced age, and it has been suggested that changes in androgen binding may be important in age-associated alterations in growth regulatory mechanisms of prostatic epithelial cells. In this study the effects of age on androgen binding characteristics in the dorsolateral prostate glands of young and aged Copenhagen rats were determined and the binding properties in the Dunning R3327/130 subline of rat prostatic adenocarcinoma were characterized. Tritium-labeled and nonlabeled methyltrienolone analogs (R1881) were used to study the binding properties of 5 alpha-dihydrotestosterone receptor in the cytosol of tumors and prostate glands.

Hormonal effects on zinc concentration and morphology of rat lateral prostate gland.

Hypophysectomized rats were injected with prolactin and/or testosterone, and luteinizing hormone (LH) and prolactin and/or follicle-stimulating hormone (FSH). Tissue from the lateral prostate was processed for spectrophotometric determination of zinc and for electron microscopy. Changes in zinc concentration, epithelial height, and morphological characteristics were used to assess the effect of hormonal replacement on functional activity.

Electron microscopic and histochemical characterization of intra-arterial cushions of the rat and porcine uterine vascular bed.

Scanning and transmission electron microscopic studies, together with histochemical investigations, were conducted on rat and porcine intra-arterial cushions from the uterine vascular bed. In the rat, the fine structure of these cushions closely resembled that previously described in the rat kidney. The cushions were composed of modified smooth muscle, circularly disposed in an incomplete, raised band surrounding the entrance to arterial branches.

Isolation, in vitro cultivation, and electron microscopy of normal and malignant prostatic epithelial cells from the Copenhagen rat.

Procedures are described for the isolation and cultivation of normal rat prostatic epithelial cells. The techniques, which involve collagenase digestion and Ficoll purification of the epithelial population, are efficient, inexpensive, and produce pure monolayers. Included is a scanning and transmission electron microscopic study comparing cells isolated in vitro to rat prostatic epithelial cells in situ.

Effects of estrogen upon the fine structure of epithelium and stroma in the rat ventral prostate gland.

We studied the effects of estradiol upon the fine structure of the rat ventral prostate, with special emphasis on the interstitial tissue. Intact and castrated rats were injected with estradiol or testosterone in combination, or with peanut oil (control). Estrogen exerted an antiandrogenic effect on the epithelium of intact animals resulting in lower epithelial height and reduction in the number of cell organelles and secretory bodies; however, the prostate gland did not atrophy to the same degree as that in castrated controls.

Spermatic granuloma of vas deferens after vasectomy in rhesus monkeys and men: light and electron microscopic study.

Spermatic granuloma of the vas deferens is a common complication of vasectomy which has received scant morphologic study. This study investigated the light and electron microscopic structure of such granulomas detected in rhesus monkeys (Macaca mulatta) and man after various modes of vasectomy and postoperative periods. Unilateral experimental vasectomy in monkeys was performed by either silk ligation or clasp occlusion; in 4 of 13 ligated animals and 5 of 5 clasp vasectomized animals granulomas developed at the site of fasectomy.

Fine structural studies of the rat vas deferens.

A fine structural study of the normal rat vas deferens was undertaken utilizing perfusion fixation. Morphological features not previously appreciated were revealed using this technique of fixation, and included the following. The rat vas deferens exhibited a gross morphological and microscopic differentiation along its length: A proximal segment was characterized by a thin muscular wall, an epithelium of low height (comparable to that of the cauda epididymidis) and a distended lumen typically filled with an accumulation of sperm; a distal segment exhibited a thick muscular wall, a convoluted mucosa, and a pseudostratified columnar epithelium with long stereocilia extending into the lumen.