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D S Coffey

Publications and source records attributed to D S Coffey.

At least 37 records · Page 2Linked to original sources
PubMed1996

There are multiple forms of glyceraldehyde-3-phosphate dehydrogenase in prostate cancer cells and normal prostate tissue.

We analyzed glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression in normal and malignant human prostate tissues, normal rat prostate, and Dunning R-3327 rat prostate cancer cell lines. We detected multiple forms of GAPDH in Dunning cell lines by two-dimensional protein electrophoresis and Western analysis. Five forms of GAPDH that differed by isoelectric point were detected for each of the two metastatic Dunning cell lines, while four or fewer forms were detected for Dunning cell lines with low metastatic ability. We also detected multiple forms of GAPDH in normal and malignant human prostate specimens by two dimensional protein electrophoresis and immunohistochemical analysis. GAPDH was undetectable in normal human prostate secretory epithelium by immunohistochemistry, but was abundant in nuclei of normal basal cells and stromal cells. In human prostate cancer specimens, there was a rough correlation between cytoplasmic staining for GAPDH and tumor grade, but GAPDH staining was extremely heterogeneous. GAPDH was abundant in nuclei of some high-grade human prostate tumors. Both of the human prostate cancer bone metastases analyzed with immunohistochemistry had markedly elevated cytoplasmic GAPDH expression. We conclude that multiple forms of GAPDH may play diverse roles in normal prostate tissue and in prostate cancer.

Adenocarcinoma↗
PubMed1996

Ability to predict biochemical progression using Gleason score and a computer-generated quantitative nuclear grade derived from cancer cell nuclei.

OBJECTIVES: To determine the ability to predict prostate cancer progression using shape, size, and chromatin texture nuclear grading features preselected by logistic regression analyses based on expert-selected prostate cancer cell nuclei captured using a computer-assisted image analysis system. METHODS: One hundred fifteen patients with clinically localized prostate cancer were identified at the Johns Hopkins medical institutions. The mean follow-up period was 10.4 +/- 1.7 years in 70 patients without disease progression, whereas the mean time to progression for the entire group was 3.8 +/- 2.5 years. Using 5-microns Feulgen-stained tissue sections, approximately 150 cancer cell nuclei were selected and captured for each case using a CAS-200 Image Analysis System. Thirty-eight different nuclear morphometric descriptors (NMDs) were calculated for each cell nucleus. The variance of the NMDs for each tumor was examined by univariate and multivariate logistic regression analyses and by Cox survival analyses to assess their ability to predict prostate cancer progression. RESULTS: Postoperative Gleason scoring was significantly correlated with disease progression (P < 0.00001; sensitivity, 73%; specificity, 84%; receiver operating characteristic curve area under the curve (ROC-AUC), 83%). Using backward stepwise logistic regression at a stringency of P < 0.05, the variances of 11 of the NMDs were found to be multivariately significant for progression prediction (P < 0.00001; sensitivity, 78%; specificity, 83%; ROC-AUC, 86%). A single value, termed the quantitative nuclear grade (QNG), was created from the variances of these, 11 multivariately significant NMDs using the logistic regression function. The QNG and the postoperative Gleason score were combined to create a model for the prediction of progression having a sensitivity of 89%, specificity of 84%, and ROC-AUC of 92%. These two parameters (QNG and Gleason score) clearly separated the patient sample into three statistically distinct risk groups and predicted the time to progression on the basis of Kaplan-Meier survival probability analysis. CONCLUSIONS: The QNG, combined with the postoperative Gleason score, may assist in the more accurate stratification of patients undergoing radical prostatectomy into low-, moderate-, and high-risk groups for cancer recurrence and may permit the early initiation of adjuvant therapy.

Adult↗
PubMed1996

Telomerase is activated in the prostate and seminal vesicles of the castrated rat.

Telomeres, the repetitive non-coding DNA sequences found at the ends of all eukaryotic chromosomes, shorten with each cell division. It has been proposed that telomere shortening may be the counting element of a mitotic clock that keeps track of cell divisions; with shortening to a critical length acting as a senescence signal underlying cellular aging. The enzyme telomerase functions to maintain telomere length, thus allowing unlimited cell division, and has been associated with cellular immortalization and cancer. Stem cells have large, perhaps unlimited, replicative capacities. Since these cells are potentially immortal, we reasoned that they might posses active telomerase. We therefore assayed for telomerase activity in the stem cell enriched pools of the androgen-depleted sex accessory tissues in the castrated male rat. Following castration, the ventral prostate and seminal vesicles of the rat involute, losing approximately 90% of their cells by 21 days. These residual glands persist, and are enriched for stem cells, being capable of fully regenerating these glands if testosterone is re-introduced into the animal. We assayed telomerase activity in extracts from normal, involuted, and regenerating ventral prostate and seminal vesicles. Normal glands were found to be telomerase negative, whereas telomerase activity appeared as these glands involuted following castration. Conversely, telomerase activity disappeared during testosterone-induced regeneration of these residual glands. These results provide strong evidence for the ability of androgen to negatively-regulate telomerase activity in stem cell populations of the rat ventral prostate and seminal vesicles. and represent the first in vivo model system for the modulation of telomerase activity.

Animals↗
PubMed1994

Molecular and cellular changes associated with the acquisition of metastatic ability by prostatic cancer cells.

Presently, one of every four cancers diagnosed in American males is of prostatic origin. Once prostatic cancer metastasizes, it is a fatal disease for which no therapy presently available is curative. Because of these facts, there is a growing interest in the early detection and screening of men for prostate cancer. Such screening could potentially identify 10 million American men with histological prostatic cancer. It is estimated that approximately 7% (700,000) of these men will eventually die from their disease if left untreated. This raises the critical question of which of the remaining 93% (9,300,000) of men with nonlethal, but potentially life-altering, histologically detectable prostatic cancer should receive therapy. There is no diagnostic method presently available which allows men with histologically detectable prostatic cancer, who require immediate therapy, to be distinguished from those requiring either delayed therapy or no treatment. Acquisition of metastatic ability by such histologically detectable prostatic cancer cells is a definitive criterion upon which to base such a diagnostic substaging method. Identification of the cellular and molecular requirements for acquisition of metastatic ability by prostatic cancer cells is needed for the development of such methods. This article will focus on what is known concerning general cellular and specific molecular changes associated with the acquisition of metastatic ability by prostatic cancer cells, and suggested areas for future studies.

Biomarkers, Tumor↗
PubMed1994

Benign and malignant prostatic neoplasms: human studies.

Because the present ability to treat and cure patients with prostate cancer is limited to those patients with pathologically organ-confined disease, it has become increasingly important to diagnose this disease at an early stage, when cure is most likely. Recent advances in imaging may allow the urologist and the pathologist to make the diagnosis of prostate cancer much earlier in the natural course of the disease. It therefore becomes imperative to have methods available to predict which patients have a high probability of progressing so that treatment can be assigned logically and appropriately. Our current methods of prognosis determination (stage and grade) do not allow accurate assessment of tumor behavior in the majority of individual patients with prostate cancer. Therefore, more accurate quantification of nuclear and cellular changes that take place as a tumor progresses to take on the aggressive (metastatic) phenotype are urgently needed. Experimental techniques have proven useful in answering these questions and now seem ready for large-scale testing in clinical studies.

Aging↗
PubMed1994

The requirement of the testis in establishing the sensitivity of the canine prostate to develop benign prostatic hyperplasia.

A long-term study on the requirement of the testis in establishing the sensitivity of the canine prostate to develop benign prostatic hyperplasia (BPH) was conducted using 23 aging beagles both with and without their testes. The dogs had received long-term restoration of testosterone and estrogen through silicone implants. When young beagles (0.5 to 1 year of age) were castrated and normal serum testosterone and estrogen levels restored during aging to 5 years, only 50% of these dogs developed BPH in the absence of their testes as opposed to 100% BPH development in intact controls. In addition, two-thirds of the prostates in the treated groups were remarkably reduced in size, being smaller than any prostate observed in the intact controls. If, following castration, the steroid restoration was withheld for 4 years during aging and subsequently administered starting at 5 years of age and continuing for a 6-month period, none of the animals developed complex BPH. Moreover, two-thirds of the prostate glands were reduced in size by more than 60% and were atrophied in spite of the maintenance of normal prostatic tissue dihydrotestosterone levels. Regardless of the time of steroid restoration to a castrate beagle, the periurethral zone of the canine prostate exhibits various degrees of atrophy indicating functional regions within the canine prostate that are sensitive to the requirements of the testes during aging. This study implicates the importance of the testis in increasing the probability and/or sensitivity for the full development of canine BPH.

Aging↗
PubMed1994

Quantitative nuclear morphometry, Markovian texture descriptors, and DNA content captured on a CAS-200 Image analysis system, combined with PCNA and HER-2/neu immunohistochemistry for prediction of prostate cancer progression.

One hundred and twenty-four localized prostate cancer patients operated on at Johns Hopkins Hospital (JHH) since 1975 were identified. The sample was optimized for evaluation of prostate cancer progression. Based upon accurate clinical histories, these radical prostatectomy patients included 50 progressors and 74 non-progressors using appearance of serum PSA as an indication of recurrence (mean follow-up = 8.6 +/- 1.8 years, range 7-15 years). All patients included in the study had no involvement of their seminal vesicles or lymph nodes at the time of prostatectomy. Average time to progression was 3.6 +/- 2 years, range of 1-8 years. Using paraffin-embedded specimens, several five micron sections were cut and placed on Probe-On slides; one slide was H&E-stained and the other was Feulgen-stained. The H&E and Feulgen-stained slides were screened and "dotted" by pathologists at JHH and CytoDynostics, Inc. A CAS-200 Image analysis system (Cell Image Systems, Elmhurst, IL) equipped with a Cell Measurement Program version 1.2 beta, was used to capture the Feulgen-stained images and to perform the calculations. From the "dotted" areas, 150 cancer cells were selected for measurement of DNA content and 27 nuclear morphometric shape and size factors, including 21 Markovian chromatin texture variables. Additional sections were used for immunochemistry staining with an alkaline phosphatase streptavidin-biotin complex stain to detect and quantitate cancer cells binding monoclonal antibodies directed against proliferating cell nuclear antigen (PCNA) and HER-2/neu antigen. All data were entered into a statistical program (STATA) for further analysis and univariate and multivariate statistical analysis was performed using logistic regression and its stepwise variant. The biomarkers of greatest utility to detect progressors when analyzed univariately included post-operative Gleason score (p = < 0.0001), HER-2/neu antigenicity (p = 0.0147), CAS-200 DNA ploidy (p = 0.008), and twelve Markovian nuclear texture and shape features (p = < 0.0001), whereas PCNA (p = 0.160) failed. The optimal set of nuclear morphometry progression tumor features were selected using backward stepwise logistic regression estimate analysis which drops variables due to collinearity. Although post-operative Gleason score is a strong univariate predictor of progression, DNA ploidy and HER-2/neu contributed significantly to further stratification of higher risk groups within the low Gleason score subpopulation. The best Markovian features combined with post-operative Gleason score generated sensitivity = 90%, specificity = 96%, positive predictive value = 94%, negative predictive value = 93% and the area under the receiver operator curve was 0.975.

Biomarkers, Tumor↗
PubMed1993

A novel M(r) 32,000 nuclear phosphoprotein is selectively expressed in cells competent for self-renewal.

We investigated the association between expression of a novel M(r) 32,000 nuclear phosphoprotein (pp32) and cell proliferation in vivo using the well-characterized physiological model of androgen-dependent regeneration of prostate in orchiectomized rats, pp32 is expressed at high levels in neoplastic cell lines and in certain anatomically defined stem cell compartments of normal human tissues such as intestinal crypt epithelial cells. Immunohistochemistry and in situ hybridization were used to monitor pp32 expression in rat ventral prostatic epithelium following castration and androgen restoration. Castrated rats retained only 6% of prostate wet weight compared to intact controls but were capable of complete gland restoration upon androgen replacement. In intact controls, pp32 expression localized to small acini at the periphery of the gland and to rare basal cells in the central regions. Ten days following castration, there was a 3,5-fold enrichment in the frequency of pp32-positive cells with greater than 56% of remaining epithelial cells expressing pp32 protein. In situ hybridization showed that all remaining epithelial cells contained pp32 mRNA. Upon testosterone replacement, pp32 expression and localization returned to that of intact controls. In order to determine the association between pp32 expression and cell division, DNA synthesis was monitored by bromodeoxyuridine incorporation during prostate involution and regeneration. Bromodeoxyuridine incorporation peaked 3 days after androgen replacement and occurred diffusely throughout the gland. Thus, pp32-positive cells are anatomically distinguishable from the population of terminally differentiating cells undergoing rapid expansion. Preliminary immunohistochemical studies of human prostatic neoplasia demonstrated increased expression of pp32 in human prostatic adenocarcinoma and prostatic intraepithelial neoplasia compared to benign prostatic hypertrophy and normal human prostate. The highest degree of expression occurred in the higher Gleason grades and prostatic intraepithelial neoplasia. This work suggests that pp32 is a nuclear protein which has a selective but presently undefined role in cells competent for self-renewal.

Adenocarcinoma↗
PubMed1993

Association of glyceraldehyde-3-phosphate dehydrogenase expression with cell motility and metastatic potential of rat prostatic adenocarcinoma.

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression is increased in Dunning R-3327 rat prostatic adenocarcinoma cell lines relative to normal rat ventral prostate tissue. GAPDH expression closely correlates with cell motility of Dunning prostate cancer cell lines and accurately distinguishes cell lines with high metastatic potential from those with low metastatic potential. Increased GAPDH expression in the cancer cell lines is not simply related to increased growth rate, since rapidly proliferating normal prostate tissue did not exhibit elevated GAPDH expression.

Adenocarcinoma↗
PubMed1993

Nuclear matrix protein patterns in human benign prostatic hyperplasia and prostate cancer.

The nuclear matrix represents the structural component of the nucleus that determines nuclear shape and higher order DNA organization. We have previously shown tissue specificity in nuclear matrix proteins (NMP), in rat sex accessory tissues, and in a rat model of prostate cancer. This study compares NMP patterns for fresh human normal prostate, benign prostatic hyperplasia (BPH), and prostate cancer for 21 men undergoing surgery for clinically localized prostate cancer or BPH. NMP patterns were compared using high resolution two-dimensional polyacrylamide gel electrophoresis. We identified by molecular weight and isoelectric point 14 different proteins that were consistently present or absent among the various tissues. One protein (PC-1), a M(r) 56,000 protein with an isoelectric point of 6.58, appeared in 14 of 14 different nuclear matrix preparations from prostate cancer and was not detected in normal prostate (0 of 13) or BPH (0 of 14). The NMP patterns are consistent with a model of disease progression in which BPH shares many of the nuclear matrix changes observed in prostate cancer.

Antigens, Nuclear↗
PubMed1992

Use of nuclear morphometry, gleason histologic scoring, clinical stage, and age to predict disease-free survival among patients with prostate cancer.

BACKGROUND: Currently, there are no accurate methods for predicting metastases or time to disease progression for patients with clinically localized prostate cancer after surgery. METHODS: In this report, histologic sections were studied from prostate cancer specimens from 100 men with clinically localized prostate cancer (clinical Stages A1 [9 cases], A2 [24 cases], B1 [27 cases], and B2 [40 cases]; pathologic Stages A1 [9 cases], A2 [22 cases], B [23 cases], C1 [8 cases], and D1 [38 cases]) to determine whether nuclear morphometry--when analyzed with clinical stage, pathologic parameters, and age in a multivariate fashion--would predict time to disease progression. RESULTS: These patients were treated with surgery alone for their clinically localized disease and were observed after surgery until disease progression or death. For each of the 100 specimens, 16 different mathematical descriptors described the shape of 150 nuclei. A series of 17 different statistical measurements were calculated to accurately describe the distribution, extremes, and variability within each descriptor. As univariate predictors, the variance of nuclear roundness, the mean of ellipticity, the Gleason score, age, and clinical stage were statistically significant predictors of disease progression when analyzed with Kaplan-Meier survival curves. A prognostic factor score calculated with multivariate analysis of clinical stage, Gleason score, age, and variance of nuclear roundness separated the patients into three statistically distinct groups and predicted time to progression by the Kaplan-Meier life table and Cox proportional hazards analysis. CONCLUSIONS: This prognostic factor score may aid in stratifying patients into high-risk and low-risk groups for testing adjuvant therapies for prostate cancer.

Adenocarcinoma↗
PubMed1992

Prediction of prognosis in untreated stage A2 prostatic carcinoma.

Carcinoma is found unexpectedly in approximately 10% or more of the 400,000 prostatectomies performed annually in the United States. Patients with Stage A2 carcinoma die of their disease in only 35% of the cases. To alter the course of disease in these patients, 65% of Stage A2 patients may be treated unnecessarily by radical prostatectomy, radiation therapy, or hormonal therapy. An accurate method to predict the outcome of patients with Stage A2 carcinoma is needed. Histologic sections from 18 patients with Stage A2 prostatic carcinoma followed without further treatment until progression, or followed without progression, were evaluated by several investigators who did not have knowledge of patient outcomes and who employed standard pathologic grading systems as well as morphometric, cytophotometric, flow cytometric, and immunohistochemical techniques. Outcome was predicted correctly by random sampled absolute (17 of 18 cases) and relative (16 of 18) nuclear roundness factor (NRF), tumor volume expressed as percent of specimen (13 of 16), primary (13 of 18), secondary (14 of 18), sum (15 of 18), and worse (14 of 18) Gleason grades and prostate-specific antigen immunohistochemical findings (13 of 18) that produced statistically significant separation of the two groups. Significant separation was not obtained with Mostofi's pattern, nuclear, sum, and worse grades, Johns Hopkins' grade, absolute tumor volume, nuclear DNA content measured by image cytophotometric study of Feulgen-stained histologic sections and flow cytometric study of propidium iodide-labeled suspensions of nuclei obtained from paraffin blocks, nonrandom sampled NRF of worse and most prevalent neoplastic areas, and prostatic acid phosphatase and peanut agglutinin immunohistochemical study. NRF measured by a random technique best predicted outcome in these patients with A2 prostatic carcinoma and should be evaluated prospectively as a means for selecting patients who require therapy.

Adenocarcinoma↗
PubMed1992

Nuclear-cytoskeletal interactions: evidence for physical connections between the nucleus and cell periphery and their alteration by transformation.

The overall coordination of cell structure and function that results in gene expression requires a spatial and temporal precision that would be unobtainable in the absence of structural order within the cell. Cells contain extensive and elaborate three-dimensional skeletal networks that form integral structural components of the plasma membrane, cytoplasm, and nucleus. These skeletal networks form a dynamic tissue matrix are composed of the nuclear matrix, cytoskeleton, and extracellular matrix. The tissue matrix is an interactive network which undergoes dynamic changes as cells move and change shape. Pathologists have long recognized cancer in pathologic specimens based on the altered morphology of tumor cells compared to their normal counterparts. The structural order of cells appears to be altered in transformed cells. This structural order is reflected in the altered morphology and motility observed in transformed cells compared to their normal counterparts, however, it is unclear whether the structural changes observed in cancer cells have any functional significance. We report here on the nature of the physical connections between the nucleus and cell periphery in nontransformed cells and demonstrate that the nucleus is dynamically coupled to the cell periphery via actin microfilaments. We also demonstrate that the dynamic coupling of the nucleus to the cell periphery via actin microfilaments is altered in Kirsten-ras transformed rat kidney epithelial cells. This loss of structure-function relationship may be an important factor in the process of cell transformation.

Acrylamide↗
PubMed1992

Effects of extracellular matrix components and dihydrotestosterone on the structure and function of human prostate cancer cells.

The extracellular matrix (ECM) has been shown to play a major role in cell structure and function. Several studies have demonstrated that the ECM can alter cell morphology and effect DNA synthesis and gene expression. The ECM also interacts with growth hormones which have been shown to be located in or near the ECM where they are believed to effect cell structure and function. In the nontransformed cell, these ECM and hormone-mediated effects appear to be tightly regulated and this is believed to be accomplished through cell receptor-tissue matrix interactions. We, therefore, undertook a study to determine the effects of a variety of ECM components and the adrogenic hormone dihydrotestosterone (DHT) on the structure and function of the human prostate cancer cell line, LNCaP. The effects of individual matrix components in the presence and absence of 1 nM DHT on the static and dynamic morphology, growth rate, and PSA production of the LNCaP cell line were studied. We determine that the ECM and DHT interact in complex ways to effect cell structure and function. DHT produced alterations in cytoplasmic structure that increased cell size and decreased the nuclear area/cytoplasmic area ratio. Dynamic cell structure as measured by cell motility was very sensitive to the ECM components and the presence of DHT. PSA and growth could be regulated by substratum and DHT and there was an inverse relationship between PSA production and growth rate. These data exemplify the complex interactions which occur between prostate cancer cells, ECM components, and exogenous DHT that are reflected in cell structure and function.

Antigens, Neoplasm↗
PubMed1992

Effect of pentosan, a novel cancer chemotherapeutic agent, on prostate cancer cell growth and motility.

Pentosan is a new chemotherapeutic drug which is currently in Phase I clinical trials. In our experimental systems, in vivo, pentosan inhibits the growth of the highly metastatic MAT-LyLu (MLL) Dunning R3327 prostate cancer cell line only at toxic doses and has no apparent effect on growth in vitro. The mechanism of tumor inhibition of this drug is unknown; however, in vitro, pentosan exhibits a potent inhibition of cell motility. Cell motility is essential for tumor cell metastasis and angiogenesis. By blocking cell motility, pentosan has the potential to inhibit both tumor growth and metastasis. We have characterized the mechanism of motility inhibition by pentosan and believe it alters cell-extracellular matrix interactions. The mechanism of motility inhibition by pentosan appears to be independent of cytoskeletal structural alterations, including changes in microfilament and microtubule networks. Pentosan acts through a different mechanism than suramin, a drug which inhibits motility through inhibition of growth factor effects. In vitro, pentosan alters cellular contacts with the extravascular matrix and inhibits cell motility. In vivo, pentosan prolongs survival of rats injected with MLL cells by 25%, but did not appear to decrease the rate of primary tumor growth or the number of metastatic lesions in the treated animals. These data suggest that, in vivo, pentosan acts through an as yet undefined mechanism.

Animals↗