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R W de Vere White

Publications and source records attributed to R W de Vere White.

13 recordsLinked to original sources
PubMed2006

The R273H p53 mutation can facilitate the androgen-independent growth of LNCaP by a mechanism that involves H2 relaxin and its cognate receptor LGR7.

Mutations in p53 occur at a rate of approximately 70% in hormone-refractory prostate cancer (CaP), suggesting that p53 mutations facilitate the progression of CaP to androgen-independent (AI) growth. We have previously reported that transfection of p53 gain of function mutant alleles into LNCaP, an androgen-sensitive cell line, allows for AI growth of LNCaP in vitro. We herein confirm the in vivo relevance of those findings by demonstrating that the R273H p53 mutation (p53(R273H)) facilitates AI growth in castrated nude mice. In addition, we demonstrate that H2 relaxin is responsible for facilitating p53(R273H)-mediated AI CaP. H2 relaxin is overexpressed in the LNCaP-R273H subline. Downregulation of H2 relaxin expression results in significant inhibition of AI growth, whereas addition of recombinant human H2 relaxin to parental LNCaP promotes AI growth. Inhibition of AI growth was also achieved by blocking expression of LGR7, the cognate receptor of H2 relaxin. Chromatin immunoprecipitation analysis was used to demonstrate that p53(R273H) binds directly to the relaxin promoter, further confirming a role for H2 relaxin signaling in p53(R273H)-mediated AI CaP. Lastly, we used a reporter gene assay to demonstrate that H2 relaxin can induce the expression of prostate-specific antigen via an androgen receptor-mediated pathway.

Androgens↗
PubMed2002

Can single dose preoperative intrathecal morphine sulfate provide cost-effective postoperative analgesia and patient satisfaction during radical prostatectomy in the current era of cost containment?

We retrospectively analyzed the analgesic efficacy and surgical outcomes of a single preoperative intrathecal long-acting morphine sulfate injection (0.25-0.5 mg) and postoperative intravenous (i.v.) ketorolac in 62 patients who underwent radical retropubic prostatectomy (RRP). Total postoperative analgesic requirement was documented along with assessment of length of hospital stay, pain control and time for resumption of normal activity. Postoperatively, 45% of patients required only nonsteroidal agents (ketorolac), whereas 55% needed a mean of 13.3 mg of supplemental i.v. morphine sulfate. Mean hospital stay was 2.3+/-0.3 days. Eighty-two per cent of patients felt the length of hospital stay adequate. Ninety-seven per cent of patients were satisfied with anesthesia selected and 95% of patients considered pain control on postoperative days 1 and 2 as effective. All patients resumed to full physical activity by 5.3+/-0.4 weeks after surgery. We conclude that a single preoperative injection of intrathecal morphine sulfate combined with i.v. ketorolac postoperatively results in effective analgesia, diminished supplemental narcotic requirement and high patient satisfaction during radical retropubic prostatectomy.

Analgesics, Opioid↗
PubMed1998

Predicting prognosis in patients with superficial bladder cancer.

Bladder cancer is the most common urologic malignancy and is expected to affect approximately 54,000 people in 1998. Superficial bladder tumors (Tis, Ta, and T1 lesions) account for approximately 70% to 80% of these malignancies. Although many advances have been made in the management of patients with superficial bladder cancer, such disease often recurs and can progress, leading to death. It is therefore imperative to find an accurate method of identifying patients at risk for disease progression. Many recent investigations have been conducted to determine whether new biological markers will help predict disease progression and, to a lesser extent, tumor response to treatment. These new markers include DNA ploidy, S-phase, certain monoclonal antibodies, the p53 (alias TP53) tumor-suppressor gene, the retinoblastoma (Rb) gene, cell adhesion molecules, and angiogenesis. It is hoped that such prognostic indicators, coupled with cytoscopic and pathologic characteristics of the tumor, will lead to selective aggressive treatment of patients at high risk for progression while sparing low-risk patients from unnecessary procedures.

Biomarkers, Tumor↗
PubMed1996

CWR22: the first human prostate cancer xenograft with strongly androgen-dependent and relapsed strains both in vivo and in soft agar.

Most patients' prostate cancers respond to androgen deprivation but relapse after periods of several months to years. Only two prostate cancer xenografts, LNCaP and PC-346, have been reported to be responsive to androgen deprivation and to relapse subsequently. Both of these tumors shrink slightly, if at all, and relapse less than 5 weeks after androgen withdrawal. After androgen withdrawal, the human primary prostate cancer xenograft CWR22 regresses markedly, and prostate-specific antigen (PSA) falls up to 3000-fold in the blood of mice. PSA usually returns to normal. In some animals, the tumor relapses and is then designated CWR22R. In these animals, PSA starts to rise approximately 2-7 months, and tumor begins to grow 3-10 months after castration. Animals with CWR22 need to be euthanized because of large tumors 6-12 weeks after the transplantation of CWR22. Androgen withdrawal prolongs life approximately 3-4-fold.

Agar↗
PubMed1996

Correlation of genetic and immunodetection of TP53 mutations in malignant and benign prostate tissues.

The prognostic value of the p53 gene (TP53), the most commonly mutated gene in human cancers, has been well established for several cancer types. However, because varying frequencies of TP53 mutations have been identified in prostatic adenocarcinoma (CaP) by genetic and immunohistochemical (IHC) studies, the role of TP53 in CaP tumorigenesis is currently unresolved. These experimental discrepancies could be caused by tissue heterogeneity within prostatic neoplasms, variations in experimental protocols, or other factors. Thus, the goal of this study was to develop a reliable IHC approach for the detection of p53 in archival prostate tissue. The authors evaluated four p53 antibodies, CM-1, 1801, DO-1, and DO-7, for their ability to reveal p53. They chose two reference CaP cell lines, 26 patient specimens (including eight benign prostatic hyperplasias (BPHs), 16 CaPs, and two lymph node metastases), one prostate and nine kidney cell lines for p53 analysis. The TP53 status of these samples was characterized using single-strand conformational polymorphism (SSCP) analysis of RNA/PCR products and sequencing. IHC detection of p53 was markedly enhanced by using the combination of microwave heat-induced antigen unmasking and a cocktail of the DO-1 and DO-7 antibodies. This approach identified 14 of 15 (93%) cell lines and patient samples having TP53 missense mutations in the exons 5 to 8 region. Of the 21 patient samples and cell lines that were either normal by SSCP or expressed p53 mutations that are not expected to stain, 18 (86%) were immunonegative. Because of this good correlation between molecular and IHC analysis, this approach may help to resolve the uncertainty about TP53 in CaP tumorigenesis.

Adenocarcinoma↗
PubMed1990

Comparison of flow cytometry to routine testicular biopsy in male infertility.

We compared DNA flow cytometry to morphologic evaluation of routine testicular biopsies as methods of monitoring spermatogenesis. The study group consisted of 14 azoospermic men and 5 others who underwent testicular surgery unassociated with fertility problems. The findings for both studies were divided into three groups: normal, moderately abnormal, and markedly abnormal. Correlations between the findings from routine biopsy and flow cytometry were good. Of 9 patients having normal testicular morphology, 7 had normal ploidy classes by DNA flow cytometry while 2 had moderately abnormal histograms. Of 5 cases with moderately abnormal morphology, 1 had normal, 1 had moderately abnormal, and 3 had markedly abnormal ploidy distributions. In 5 cases described as Sertoli cell only, all DNA histograms were markedly abnormal, consisting almost exclusively of diploid cells. DNA flow cytometry of testicular biopsies and aspirates has been demonstrated to be a rapid, reproducible, and objective approach in evaluating the infertile male and is a promising method to investigate spermatogenesis in an outpatient clinic in lieu of formal testis biopsy.

Biopsy, Needle↗
PubMed1989

Check samples for laboratory self-assessment in DNA flow cytometry. The National Cancer Institute's Flow Cytometry Network experience.

The National Cancer Institute's Flow Cytometry Network (NCI-FCN) is attempting to facilitate the transfer of flow cytometry (FCM) of exfoliated bladder cells from the research laboratory to the clinical laboratory. Demonstrating interinstitutional consistency in FCM analysis of replicate specimens simulating clinical barbotage specimens, fixed to allow easy transportation and storage at room temperature was one specific objective. Simulated barbotage specimens were prepared by mixing cultured aneuploid bladder carcinoma cells with normal or mitogen-stimulated peripheral blood mononuclear cells in different ratios. The samples were fixed in 10% formalin for 30 minutes, stored in buffer, and enucleated with pepsin, pH 1.5, before staining with propidium iodide for FCM DNA analysis. Preservation in ethanol or other common DNA cytochemical reagents was found to be unsatisfactory. In contrast, the formalin-fixed samples showed excellent preservation of quantitative DNA fluorescence and coefficient of variation of histogram peaks for over 2 weeks. Exchange of eight fixed specimens among five network laboratories that analyzed them as "unknowns" showed good overall agreement on histogram data and interpretation, although some noteworthy interlaboratory differences were found. This technique could be used for self-assessment surveys of clinical laboratory performance in DNA FCM of bladder barbotage specimens.

Cell Count↗
PubMed1989

Measurement variability in DNA flow cytometry of replicate samples.

A Bladder Cancer Flow Cytometry Network study has been carried out aimed at identification of the sources of inter- and intralaboratory variability. Replicate "cocktail" samples containing a mixture of peripheral blood lymphocytes and an aneuploid cell line and samples of peripheral blood lymphocytes serving as a DNA reference standard were distributed to five network laboratories. The samples were stained for DNA using propidium iodide, with each laboratory using its own staining protocol. Sets of these samples were analyzed by flow cytometry to obtain cellular DNA distributions. DNA index and hyperdiploid fraction were calculated for each histogram using an automated technique. Results were evaluated by analysis of variance to identify sources of variability. Three important sources of variation were found that affect flow cytometry in general and- the transportability of flow cytometry results to routine clinical use in particular. The significant variation among laboratories that is constant across time most probably represents stable differences in instrumentation, instrument set-up, and laboratory techniques. This variation can be compensated for, if it is known and stable, to develop transportable classification criteria. The second type of variation, termed the interaction component, represents differences among laboratories that are not constant across time. Sources of this variation include inconsistency in sample preparation, staining, and analysis. The elimination of this type of variation is required for meaningful comparison of data within and among laboratories and the creation of interlaboratory data-bases. The third type of variation represents pure measurement variability and affects the sensitivity of the technique.

Cell Line↗
PubMed1989

RAS enzyme-linked immunoblot assay discriminates p21 species: a technique to dissect gene family expression.

The members of the RAS gene family of protooncogenes are of implied biological significance in oncogenesis. The precise role of these genes is unclear. One difficulty has been the inability to discriminate the individual p21 protein products of various ras genes in cell lines, de novo human tumors, and related normal tissues. In this report, specific proteins of the human c-Ha-ras-1, c-Ki-ras-2, and c-N-ras genes have been detected and discriminated by the differential use of various antisera recognizing these p21s. This enzyme-linked immunoblot assay utilizes a double antibody system in which monoclonal antibodies are initially used to immunoprecipitate the p21ras proteins. Immunoprecipitates are then subjected to one-dimensional Western blot analysis utilizing other antibodies raised against p21s, coupled with nonradiolabeled enzyme-linked colorimetric detection. By direct detection, the specific products of the three human ras genes can be discriminated. In addition, we describe the generation and characterization of a new anti-p21c-N-ras-specific antibody. The simultaneous expression into protein of multiple ras genes is unequivocally demonstrated in both homogeneous cell lines and heterogeneous human tissues. This new technique is also applicable for discrimination of the protein products of other gene families.

Animals↗
PubMed1989

Deoxyribonucleic acid flow cytometry of benign prostatic disease.

Deoxyribonucleic acid flow cytometry was performed on aspirated prostatic cells from 198 patients who had benign cytological or histological findings. Unsatisfactory acellular histograms were obtained from 10.6 per cent of the cases. Three-fourths of the satisfactory samples (more than 5,000 cells after subtracting debris) showed the expected single peak deoxyribonucleic acid diploid to near diploid histograms. Unexpectedly, the remaining samples were deoxyribonucleic acid aneuploid, most having 2 peridiploid peaks (deoxyribonucleic acid index 0.82 to 1.31). Usually, proliferation was low with less than 20 per cent hyperdiploid cells and with 2.5 +/- 1.5 per cent G2 cells. In 10 per cent of the single peak histograms there was evidence of inflammation, identified as an increase in hyperdiploid cells without an increased percentage of G2 cells but with a tail of high channel values. The aforementioned histogram features were considered to be benign findings. Seven per cent of the samples had deoxyribonucleic acid histograms suggestive of prostate cancer. Of these samples 7 had diploid or peridiploid aneuploid histograms with high proliferation (more than 20 per cent hyperdiploid cells with 8.5 +/- 3.8 per cent G2 cells), while 5 had histograms with deoxyribonucleic acid aneuploidy other than peridiploidy.

DNA↗
PubMed1988

Interinstitutional variability in DNA flow cytometric analysis of tumors. The National Cancer Institute's Flow Cytometry Network Experience.

Flow cytometric DNA analysis of human urinary bladder specimens may be clinically useful for prognosis in transitional cell (urothelial) carcinoma and for detecting recurrence after treatment. However, many important methodological differences exist among institutions which have described this technique, and it has not previously been shown that data from different institutions are comparable. The National Cancer Institute has created a Flow Cytometry Network to address the need for technology assessment of flow cytometry. This report describes the independent flow cytometric analysis and interpretation of "unknown" paraffin-embedded bladder tumor specimens by the five Network institutions. Although important differences in method existed among the institutions, substantial agreement was achieved in actual data generated and their interpretation. This suggests that a consensus regarding acceptable laboratory performance of this technique could be reached, which should facilitate its more widespread clinical implementation.

Carcinoma, Transitional Cell↗
PubMedDate not supplied

False DNA aneuploidy in canine and human neoplasms.

In most cases, the appearance of aneuploid peaks in DNA histograms may be an artefact of tissue preparation or it may reflect non-stoichiometric dye binding of a cellular subpopulation rather than true DNA aneuploidy. This report reviews how false DNA aneuploidy can be recognized and eliminated from sample submitted for DNA flow cytometric analysis.

Aneuploidy↗