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F M Waldman

Publications and source records attributed to F M Waldman.

At least 91 records · Page 5Linked to original sources
PubMed1993

5-Bromodeoxyuridine incorporation and PCNA expression as measures of cell proliferation in transitional cell carcinoma of the urinary bladder.

Cell proliferation in 66 transitional cell carcinomas of the human urinary bladder was evaluated using immunohistochemical detection of in vitro 5-bromodeoxyuridine (BrdUrd) incorporation and of proliferating cell nuclear antigen (PCNA). The labeling index (LI) was defined as percent of labeled nuclei for 2000 tumor nuclei counted. The BrdUrd LI ranged from 0.2% to 38.9%, geometric mean = 8.4% (n = 61), and the PCNA LI ranged from 0.4% to 64.1%, geometric mean = 12.7% (n = 60). For the 55 tumors that were stained by both procedures, the BrdUrd LI showed a highly significant regression on the PCNA LI (BrdUrd LI = 0.74 * PCNA LI, R2 = 0.71, p < 0.0001, coefficient of variation of residual = 17.7%, log transformed data). When compared to clinical and histopathologic criteria, both labeling indices were substantially lower in low grade (Grade 1) versus high grade (Grades 2 and 3) tumors and in Ta tumors versus higher stage T1, T2, and T3 tumors. These studies show that BrdUrd incorporation can be used reliably to measure cell proliferation in fresh bladder tissue, that PCNA labeling is a similar measure of cell proliferation, and that both measures are low in tumors of low histopathologic grade and stage.

Aged↗
PubMed1993

Effects of short-term culture on benign and malignant human breast epithelium analyzed by image analysis.

The ability to culture malignant breast cells is crucial to the success of many scientific studies. However, short-term cultures of breast cancers are composed predominantly of DNA diploid cells, leading to doubt regarding the presence of bonafide cancer cells in these cultures. Morphology by conventional light microscopy is not helpful since cultured benign cells take on features usually associated with malignancy. In this study we examined by image analysis both benign and malignant breast cancer cells before and after culture. Consistent changes in both benign and malignant cells were found following culturing. There also were consistent differences distinguishing the cultures derived from benign and malignant specimens. While the features used were not sufficiently powerful to identify individual cells or cultures as benign or malignant, our results strongly suggest that malignant breast cells do indeed grow in short-term cultures.

Adult↗
PubMed1992

ERBB2 amplification in breast cancer analyzed by fluorescence in situ hybridization.

We illustrate the use of fluorescence in situ hybridization (FISH) for analysis of ERBB2 oncogene copy number, the level of amplification (here defined as the ratio of ERBB2 copy number to copy number of chromosome 17 centromeres), and the distribution of amplified genes in breast cancer cell lines and uncultured primary breast carcinomas. The relative ERBB2 copy number determined by FISH in 10 breast cancer cell lines correlated strongly with Southern blot results (r = 0.98) when probes for an identical reference locus were used in the two methods. Metaphase analysis of cell lines showed that amplified ERBB2 copies always occurred in intrachromosomal clusters but that the number and chromosomal location of these clusters varied among the cell lines. In interphase nuclei of primary tumors showing ERBB2 amplification (10/44), ERBB2 copies were seen as one to four clusters, also suggesting intrachromosomal localization. Regardless of the average level of amplification, all these tumors contained highly amplified cell subpopulations with at least 25, and sometimes more than 100, ERBB2 copies per cell. Tumors that did not show amplification by FISH (34/44) had an average of one to five ERBB2 copies scattered randomly in the nuclei and completely lacked cells with high copy levels. FISH results on primary tumors were concordant with slot blot results on amplification and with immunohistochemical detection of overexpression. Quantitative analysis of ERBB2 amplification by FISH may improve prognostic assessments based on the pattern of amplification and detection of heavily amplified tumor cell subpopulations.

Breast Neoplasms↗
PubMed1992

Deletion of chromosome 17p loci in breast cancer cells detected by fluorescence in situ hybridization.

Allelic loss of tumor suppressor genes on chromosome 17p has been implicated in the progression of breast cancer. This is in principle detectable by fluorescence in situ hybridization if the loss occurs by deletion. In order to determine if detectable deletions occur in primary breast cancer, we used dual-color hybridization with chromosome 17 pericentromeric and region-specific DNA probes to study 19 primary breast cancers. The copy numbers of 17 centromere and 17p13.1 sequences were compared with the loss of heterozygosity (LOH) for probe YNZ22 at 17p13.3 detected by restriction fragment length polymorphism. Nine of 11 cases showing LOH also showed the major population of nuclei with a deletion. The remaining two tumors with LOH were trisomic for both the centromere and 17p13.1 cosmid. In contrast, seven of eight tumors without LOH had no deletions by fluorescence in situ hybridization. These data suggest that the dominant mechanism of allelic loss at 17p in breast cancer is a physical deletion and that analysis of deletions by fluorescence in situ hybridization is a rapid and sensitive approach to studying chromosomal aberrations.

Alleles↗
PubMed1992

Detection of retinoblastoma gene copy number in metaphase chromosomes and interphase nuclei by fluorescence in situ hybridization.

Fluorescence in situ hybridization (FISH) was applied to detect the copy number of the retinoblastoma (RB1) tumor suppressor gene in metaphase chromosomes and interphase nuclei. We used 14 lambda phage clones spanning the whole RB1 gene region as a probe and obtained a specific hybridization signal in normal metaphase chromosomes at 13q14. Normal interphase nuclei showed two RB1 signals in about 90% of cases, whereas two cell lines with cytogenetically defined deletions involving the RB1 gene showed only one hybridization signal in about 80% of the nuclei. Analogous changes were detected in metaphase chromosomes. Multicolor FISH with subsets of the phage clones allowed visualization of subregions within the 200-kb gene in interphase nuclei. Analysis of clinical breast cancer samples showed that most of the cells contained two copies of the RB1 gene, even when restriction fragment length polymorphism analysis showed loss of heterozygosity (LOH) at the RB1 locus. This indicates that LOH at the RB1 locus in breast cancer cells probably involves mechanisms other than physical deletion.

Breast Neoplasms↗
PubMed1991

Centromeric copy number of chromosome 7 is strongly correlated with tumor grade and labeling index in human bladder cancer.

The relationship between interphase cytogenetics and tumor grade, stage, and proliferative activity was investigated in 27 transitional cell carcinomas of the urinary bladder. Using fluorescence in situ hybridization with chromosome-specific DNA probes, the copy number of pericentromeric sequences on chromosomes 7, 9, and 11 was detected within interphase nuclei in touch preparations from tumor biopsies. Monosomy of chromosome 9 was detected in 9 of 22 cases (41%), while tetrasomy for chromosomes 7 and 11 was detected in 10 of 26 (38%) and 6 of 23 (26%) cases, respectively. Copy number of chromosome 7 was the most highly correlated with increasing tumor grade (r2 = 0.616, P less than 0.001, Spearman rank correlation) or increasing pathological stage (r2 = 0.356, P less than 0.002). Copy number for chromosome 9 did not correlate with either grade or stage (P greater than 0.05). Tumor labeling index (LI) was determined after in vitro 5-bromodeoxyuridine incorporation, while proliferating cell nuclear antigen LI was determined immunohistochemically. Increasing LI by either method correlated with increasing copy number for all three chromosomes tested (r2 = 0.473, P less than 0.002 for 7; r2 = 0.384, P less than 0.01 for 11; and r2 = 0.316, P less than 0.05 for 9). Since high tumor grade, stage, and LI are all indicative of more aggressive tumor behavior and worse prognosis, these findings suggest that polysomy, especially for chromosome 7, may be highly predictive for bladder tumor aggressiveness.

Aged↗
PubMed1991

Loss of heterozygosity on the short arm of chromosome 17 is associated with high proliferative capacity and DNA aneuploidy in primary human breast cancer.

Loss of heterozygosity (LOH) on the short arm of chromosome 17 (17p) was found in 27 of 52 (52%) previously untreated primary breast cancers. There was a significant correlation between this 17p allelic loss and two parameters associated with aggressive tumor behavior: high cellular proliferative fraction and DNA aneuploidy. These correlations with high cellular proliferative fraction and DNA aneuploidy were not found in tumors with LOH at nine other chromosome locations. The p53 gene, a putative tumor suppressor gene located at 17p13, was examined for aberrations to determine whether it is the target for the 17p LOH in breast cancer. Unlike other types of human cancer, there were no homozygous deletions or rearrangements of the p53 gene, and only 2 of 13 (15%) were mutated in the conserved region where mutational "hot spots" have been previously located. Therefore, we hypothesize that, in breast cancer, either loss or inactivation of gene(s) on chromosome 17p other than the p53 gene or a different mechanism of p53 gene inactivation may be responsible for the observed high labeling index and DNA aneuploidy associated with LOH at 17p.

Base Sequence↗
PubMed1991

Retinoblastoma cell cycling.

Techniques for the measurement of bromodeoxyuridine (BrdUrd) positive cells generally include either microscopic evaluation of paraffin embedded sections or measurements on cell suspensions using a fluorescent activated cell sorter. The accuracy of these measurements and their correlations can be affected by a number of technical and intrinsic tumor factors. Extrinsic parameters including degree of necrosis and tumor growth fraction are less easily analyzed in BrdUrd stained material. Retinoblastoma tumor cell cycling was prospectively studied in 11 children using in vivo and one child using in vitro BrdUrd. BrdUrd measurements were made by staining cell suspensions or sections of paraffin embedded tumor and analyzing by microscopy. Approximately 14% of viable cells were in the synthesis-phase of the cell cycle. The correlation between BrdUrd in cell suspensions and BrdUrd in paraffin embedded sections did not reach significance (r = 0.48). DNA analysis of these tumors was also performed using flow cytometry. Nine tumors were found to have a normal diploid DNA content, one had a G1 peak below the diploid control, two had a G1 peak above the diploid control, and one had two G1 peaks (a diploid and a hyperdiploid peak). There was no correlation between abnormal DNA content and the percent of cells in synthesis.

Bromodeoxyuridine↗
PubMed1991

Interphase cytogenetics of a male breast cancer.

Direct interphase cytogenetic analysis was performed on nuclei from a male breast tumor using fluorescence in situ hybridization (FISH). DNA probes specific for repetitive pericentromeric regions on chromosomes 1, 7, 9, 11, 15, 17, 18, X, and Y were used to determine chromosome copy numbers in interphase tumor cells. Copy number distributions varied greatly between chromosomes, showing major tumor populations with on (Y), two (X,9), three (11, 15, 18), and four (1, 7, 17) copies of the pericentromeric targets. The X chromosome was present in two copies in 84.7% of tumor nuclei, with the balance being primarily monosomic. Normal skin fibroblasts cultured from the same patient showed 99% monosomy X. The Y chromosome showed a minor population (12%) with two copies. The DNA index of the tumor was 2.0 as determined by flow cytometry. The proliferative activity of the tumor cells was simultaneously analyzed using detection of in vivo bromodeoxyuridine (BrdU) incorporation. The BrdU labeling index was 13.2%.

Adult↗
PubMed1991

Simultaneous analysis of chromosomal aneusomy and 5-bromodeoxyuridine incorporation in MCF-7 breast tumor cell line.

We describe a new method to determine simultaneously both proliferative status and chromosome copy number within individual interphase cells. The MCF-7 human breast cancer cell line was used as a model system to characterize proliferative activity in karyotypically defined cell subpopulations. Cells were labeled with bromodeoxyuridine (BrdU) in vitro and incorporation was monitored with IU4 mouse anti-BrdU. Biotinylated, digoxigenin-labeled, or acetylamino-fluorene-conjugated repetitive sequence DNA probes were hybridized to target interphase nuclei. Three-color fluorescence labeling allowed simultaneous detection of two chromosome pairs and designation of cells undergoing DNA synthesis. This technique may also be used for simultaneous characterization of proliferative and karyotypic heterogeneity in primary human tumors.

Aneuploidy↗
PubMed1991

A comparison between bromodeoxyuridine and 3H thymidine labeling in human breast tumors.

The fraction of tumor cells in the DNA synthesis (S) phase of the cell cycle is a strong prognostic indicator in human breast cancer. Most studies measuring S-phase in primary tumors have used either in vitro labeling with 3H thymidine or DNA flow cytometry. The former involves a cumbersome and time-consuming radioactive assay, while the latter is heavily dependent on the quality of the preparation and the effectiveness of the algorithms used. In this study, in vivo or in vitro labeling with bromodeoxyuridine (BrdUrd) was compared with in vitro labeling using 3H thymidine in a series of 33 human breast tumors. Thymidine labeling showed strong correlation with both in vitro (r = 0.96) and in vivo (r = 0.83) BrdUrd incorporation. The reliability between observers was higher for BrdUrd counting (r = 0.94) than for thymidine counting (r = 0.87). The mean labeling index of 15 tumors labeled in vivo with BrdUrd was 5.9% compared to 4.7% for 18 tumors labeled in vitro (p = 0.34). There was poor correlation between flow cytometric and microscopic analysis of BrdUrd incorporation (r = 0.37). We conclude that microscopic analysis of in vivo or in vitro BrdUrd incorporation is a rapid and reliable method to estimate breast tumor proliferation.

Analysis of Variance↗
PubMed1991

Proliferation of normal breast epithelial cells as shown by in vivo labeling with bromodeoxyuridine.

The proliferative activity of normal acinar and ductal breast epithelial cells was studied by in vivo labeling with 5-bromodeoxyuridine (BrdUrd) in 26 cases with concurrent breast carcinoma. The BrdUrd-labeled cells were recognized in histologic sections of paraffin-embedded tissue, using an anti-BrdUrd antibody and an immunoperoxidase reaction. The percentage of BrdUrd-labeled cells showed great variability for both acinar (0% to 2.66%; mean, 0.70%; standard deviation [SD], 0.80%) and ductal cells (0% to 1.99%; mean, 0.51%; SD, 0.57%). The fraction of proliferating epithelial cells declined with the age of the patients and was significantly higher in premenopausal women (1.16% +/- 0.85% for acinar and 0.94% +/- 0.60% for ductal cells) as compared with the postmenopausal women (0.27% +/- 0.46% for acinar and 0.17% +/- 0.22% for ductal cells), P less than 0.01 for acinar and P less than 0.001 for ductal cells, respectively. In some patients, great variability in distribution of proliferating acinar and ductal cells among different lobules and ducts was observed. No difference was found in the number of proliferating acinar and ductal cells situated near or far from their corresponding tumors. No correlation was seen between cell proliferation of normal acinar or ductal cells and cell proliferation of the respective tumors.

Adult↗
PubMed1990

Disruption of folate and vitamin B12 metabolism in aged rats following exposure to nitrous oxide.

The ability of nitrous oxide (N2O) to disrupt folate and vitamin B12 metabolism was examined in young (2-month), middle-aged (12-month), and elderly (24-month) Fischer 344 rats. Abnormalities in folate metabolism were assessed in a noninvasive manner by measuring the urinary excretion of formic acid and formiminoglutamic acid (FIGLU), compounds that are elevated in the urine of mammals with a deficiency in folate. After a 6-h exposure to 60% N2O/40% O2, urinary formic acid excretion increased 3- to 25-fold the first day following N2O exposure and returned to background levels by the second day after exposure in all age groups. Urinary FIGLU excretion increased 100- to 300-fold in the first day following N2O exposure, with the highest FIGLU excretion rates found in the elderly rats and the lowest in the young rats. By the second day after N2O exposure, FIGLU excretion rates returned to baseline levels in all age groups. Plasma folate progressively decreased with increasing age, whereas no age-dependent changes were observed in red cell folate, liver folate, or plasma vitamin B12 levels. The elderly rats demonstrated the highest vitamin B12 content in the liver and the lowest vitamin B12 content in the kidney compared to the other age groups. Hepatic methionine synthase activities (measured 16-21 days after N2O exposure) were elevated in the elderly compared to the middle-aged or young rats, but methionine synthase activities in kidney and brain were not different among the three different age groups. It was concluded that in rats, aging per se only slightly influences the disruption of folate metabolism produced by exposure to N2O.

Aging↗
PubMed1990

Effect of nitrous oxide on folate and vitamin B12 metabolism in patients.

Exposure to nitrous oxide (N2O) markedly enhances excretion of formic acid and formiminoglutamic acid (FIGLU) in the urine of rats, suggesting a disruption in the normal pathways of folic acid metabolism secondary to an N2O-induced inactivation of methionine synthase. We tested whether surgical patients (23 having total hip replacements and 26 having resection of acoustic neuromas) exposed to isoflurane alone or combined with N2O responded similarly. We found no increase in urinary formic acid and FIGLU in patients exposed to N2O for hip replacement, but a small, transient increase in the FIGLU-to-creatinine ratio in those undergoing resection of acoustic neuromas (mean duration of anesthesia = 9.3 h). This increase peaked at the end of anesthetic exposure and returned toward control levels by the first day after anesthesia and surgery. Low preoperative levels of red blood cell folate and low-normal levels of serum vitamin B12 did not predict an increase in formic acid or FIGLU in response to N2O. Although an occasional patient may prove highly susceptible to and develop signs of severe vitamin B12 and folic acid deficiency after exposure to N2O, our findings suggest that this is a rare event.

Adult↗
PubMed1990

Hematologic effects of nitrous oxide in surgical patients.

Nitrous oxide can cause hematologic abnormalities, including death, if it is administered for several days. However, the adverse hematologic effects of its use for surgical anesthesia are unclear. Accordingly, we have studied the hematologic responses of patients undergoing procedures involving hematologic stress or prolonged anesthesia with and without nitrous oxide. We measured red cell count, hemoglobin concentration, mean red cell volume, reticulocyte count, platelet count, mean platelet volume, blood leukocyte level, and leukocyte differential in patients undergoing total hip arthroplasty or removal of an acoustic neuroma. Nitrous oxide did not affect the production of red blood cells or platelets. Nitrous oxide treatment was associated with an increase in postoperative leukocyte levels that was modestly but significantly smaller than that found in patients not given nitrous oxide. There was no evidence that this small decrease in maximal leukocytosis adversely affected clinical outcome.

Aged↗
PubMed1988

Protein-tyrosine kinase activity and pp60v-src expression in whole cells measured by flow cytometry.

The expression and phosphotyrosine activity of pp60v-src were measured in the B31 avian sarcoma virus-transformed rat cell line by flow cytometry using monoclonal antibodies against pp60v-src (EB7) and phosphotyrosine (1G2). Although the immunocytochemical staining was markedly heterogeneous, binding of both antibodies was significantly greater to B31 cells than to untransformed Rat 1 cells. Binding of 1G2 to phosphotyrosine residues was specific; it was entirely inhibited by adding excess phenylphosphate but was not affected by phosphoserine or phosphothreonine. The relationship between the amount of phosphorylated tyrosine measured by our FCM technique and total cellular phosphotyrosine measured by phosphoamino acid analysis was linear in vanadate-treated BALB/c 3T3 cells. Treatment of B31 cells for 48 h with herbimycin A, a benzenoid ansamycin antibiotic, to decrease the expression and tyrosine kinase activity of pp60v-src caused reductions of 42% in anti-pp60v-src and 58% in anti-phosphotyrosine antibody immunofluorescence. DNA staining with the fluorescent dye propidium iodide showed no cell cycle specificity in the binding of either antibody. Herbimycin A also caused the transformed cell line to revert to the morphology, actin configuration, and growth behavior of untransformed cells; these changes were reversed within 12 h after removal of the drug. Flow cytometric evaluation of tyrosine kinase expression and activity was fast and easy, and the results correlated well with other measures of cell phenotype. This technique can be used to quantitate the effects of drugs on oncogenic proteins such as pp60v-src and their associated tyrosine kinase activity.

Actins↗
PubMed1988

Biologic priming of neutrophils in subcutaneous wounds.

Migration of neutrophils from blood into tissue is a complex response by circulating cells to chemotactic stimulation. Previous studies of the functional changes induced by this process have produced variable results. We compared neutrophils isolated from blood and from subcutaneous wounds in rabbits using established assays for adherence, chemotaxis, superoxide anion production, and hydrogen peroxide production. No differences in adherence to biologic surfaces or chemotaxis toward activated plasma were found. However, our results confirm the observation that wound neutrophils are "primed" for increased production of oxygen radicals. Primed responses were observed for both soluble (formyl methionyl leucylphenylalanine, phorbol myristate acetate) and particulate (opsonized zymosan) stimulants. Priming was also observed for peritoneal exudate neutrophils. The data suggest that the process of extravascular migration includes priming of the superoxide generating system.

Animals↗