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J S Coon

Publications and source records attributed to J S Coon.

At least 55 records · Page 3Linked to original sources
PubMed1989

Ethanol fixation of bladder irrigation specimens for flow cytometric analysis. A multiinstitutional study from the bladder cancer flow cytometry network.

Ethanol preservation of voided and catheterized urine has long been the standard for urinary cytologic study. In this report ethanol preservation of bladder irrigation specimens was evaluated for flow cytometric analysis in a multiinstitutional study requiring specimen transport. Specimens from ten patients obtained at one center were preserved for varying periods of time in 50% ethanol, then distributed by express mail to four other participating centers, up to 3000 miles distant. On receipt, from 1 to 3 weeks after collection, the samples were processed and examined by flow cytometric study using propidium iodide as the fluorochrome. Forty-six of the 50 (92%) analyzed specimens gave satisfactory histograms. In 41 of the 46 adequate samples (89%), an aneuploid peak in the alcohol preserved (propidium iodide stained) specimen correlated well with the fresh (acridine orange stained) specimen. However, there was variable loss of DNA stainability with a broadening of the coefficient of variation in some alcohol-preserved specimens and an increase in cellular debris so that measurements of DNA index and percent hyperdiploid cells were considered unreliable. The authors conclude that ethanol preservation of bladder irrigation specimens for short periods of time may be a feasible alternative when flow cytometric analysis cannot be carried out on fresh specimens, but that this is not optimal fixation for specimens that must be transported and further studies of other fixatives are recommended.

Aneuploidy↗
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

Comparison of image analysis of imprints with flow cytometry for DNA analysis of solid tumors.

Quantitative analysis of cellular DNA content may be clinically useful for several solid tumors. The technology for this analysis by flow cytometry or image analysis has existed for several years but has not been widely used, except in a handful of specialized research institutions. Recently, however, relatively inexpensive image analyzers intended for use by hospital pathologists have been introduced that can analyze DNA content from cytology or imprint specimens which are readily obtainable from solid tumors. We report here an assessment of this technology for analysis of tumor imprint specimens, using flow cytometry of tissue blocks as the standard for comparison. We used image analysis equipment on Feulgan-stained imprint preparations from 31 tumors and compared the histograms with those obtained by flow cytometric analysis of archival tissue blocks from the same tumors. The ploidy descriptors (diploid, tetraploid, and aneuploid) were concordant for the two methods in 27 specimens, with three specimens yielding discordant results and one specimen considered unevaluable by image analysis. The image analysis method using imprints appeared to have several advantages over flow cytometry, including lower instrument cost, no need to dissociate paraffin blocks or fresh tissue, and ability to analyze very small samples. Somewhat lower resolution of the histograms, extremely localized tissue sampling, and possibly greater risk of occasionally obtaining unevaluable preparations were disadvantages. Microcomputer-based image analysis performed on imprints appeared to be a viable alternative to flow cytometric analysis of tissue blocks for quantitative DNA analysis of tumor specimens.

Aneuploidy↗
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↗
PubMed1988

Comparison of automated and manual techniques for analysis of DNA frequency distributions in bladder washings.

Quantitative methods for interpretation of flow cytometry DNA histograms are required for the widespread clinical use of this technology. The usefulness of a histogram analysis technique in this setting requires that it be operator independent, easy to implement in a clinical laboratory, and provide high sensitivity to the desired information. Additionally, the technique must be tolerant of the relatively low signal-to-noise ratios often found in DNA distributions obtained from clinical samples. Among the factors that have been used to assess the malignant potential of tumors are the presence of an aneuploid population, the proportion of hyperdiploid cells, the width of the G1 peak, the DNA index, and the fraction of cells in S. A computer-based method has been developed for extraction of the above-mentioned features from DNA histograms. The program detects peaks in the histogram and uses straight-line fits to the cumulative frequency distribution to define cell population bounds. A test set of 44 histograms compiled from bladder irrigation specimens obtained from patients with a present or past history of transitional cell carcinoma (TCC) was analyzed by five collaborating laboratories forming a Network sponsored by the National Cancer Institute (NCI). This test set was used to evaluate the performance of the computer-based method by comparing results with those of four expert observers. In this preliminary analysis, perfect agreement was found in the detection of aneuploid cell populations by all observers and the computer-based method. Correlation of percent hyperdiploid cell fraction was also excellent.(ABSTRACT TRUNCATED AT 250 WORDS)

Algorithms↗
PubMed1988

Induction of reversible changes in cell-surface glycoconjugates and lung colonization potential by 13-cis retinoic acid.

Murine squamous carcinoma cells (KLN205) grown in a medium supplemented with the retinoid, 13-cis retinoic acid (RA), had dose-dependent, selective increases in the expression of certain lectin receptors, which correlated with a dramatic decrease in the ability to form pulmonary colonies (P = .0003) (Couch MJ, Pauli BU, Weinstein RS, Coon JS: JNCI, 78:971-977, 1987). These findings suggest a possible relationship between the RA-induced glycoconjugate alterations and the decreased experimental metastatic behavior. We further define the mechanism of RA's action. The finding that RA treatment (5 X 10(-6) M, 5 X 10(-7) M) did not perturb the cell cycle of KLN205 cells provides further proof that the decreased metastatic behavior is not attributable to any inhibition in the rate of growth or to alterations in the cell cycle. Furthermore, since stable subpopulations with variable lectin binding could not be detected, the mechanism of RA's action does not appear to be due to selection of variant tumor-cell subpopulations. Finally, in a series of experiments designed to determine the reversibility of the RA treatment, the RA-induced decrease in metastatic behavior reverted back to a more metastatic state in the same time frame (3 days) as the reversion of the RA-induced changes in cell-surface glycoconjugate expression. This reversion provides further evidence for a close relationship between the RA-induced modulation of tumor cell-surface glycoconjugate expression and the decreased metastatic behavior; it suggests that transient, reversible modulation of the tumor cell surface may play a role in determining metastatic behavior.

Animals↗
PubMed1988

The prognostic value of DNA ploidy combined with histologic substaging for incidental carcinoma of the prostate gland.

Although current methods of histologic substaging for incidental prostatic carcinoma are useful, they offer only general indications of potential tumor behavior. To further define the biologic tendencies of stage A cancers, an examination was made of the role of DNA ploidy combined with histologic staging in archival material selected to achieve both a representative sample and long-term follow-up. With histology alone, 36% of stage A2 cancers and 9% of A1 neoplasms were progressive. Adding DNA flow cytometry to histology resulted in a significant improvement in the capacity of pathologic evaluation to predict outcome. Progression occurred in 67% of aneuploid stage A2 prostate cancers and in none of the nonaneuploid stage A1 tumors. Despite current limitations in the interpretation of DNA histograms from archival tissue, flow cytometry has significant potential in the pathologic evaluation of incidental prostatic carcinomas.

Aged↗
PubMed1988

Prognostic significance of DNA aneuploidy in stage I cutaneous melanoma.

The prognostic significance of DNA aneuploidy was studied restrospectively in 177 Stage I cutaneous melanomas. DNA content was determined by flow cytometry of propidium iodide-stained nuclei recovered from formalin-fixed, paraffin-embedded material. Of 162 evaluable histograms, 124 were diploid, 35 aneuploid, and 3 tetraploid. Aneuploidy strongly correlated with established predictors of unfavorable prognosis, namely, thickness p less than .005, level p less than 0.005, ulceration p less than 0.005, and presence of vertical growth phase p less than 0.02. Overall, aneuploidy was strongly correlated with recurrence (p less than 0.005) and shorter disease-free survival (p less than 0.0001). Aneuploidy was an independent predictor of recurrence for tumors less than 1.5 mm thick (p less than 0.0001) and greater than or equal to 3 mm thick (p = 0.031). For melanomas 1.5-2.9 mm thick, aneuploid tumors had a 27% higher recurrence rate than diploid tumors (63% vs. 36%). This was not statistically significant (p = 0.247). In a multivariate analysis of common predictors stratified by thickness, DNA aneuploidy was the most significant independent parameter (p less than 0.002). DNA content appears to be an important stratification parameter for Stage I cutaneous melanoma.

Actuarial Analysis↗
PubMed1987

Multiparameter flow cytometric analysis of colon polyps.

Sixty-eight colonic polyps of various histologic types were studied using retrospective flow cytometric (FCM) DNA analysis to determine the prevalence of aneuploid cell populations and whether they were associated with any particular histologic features. Overall, 13 of 68 polyps (19%) contained DNA-aneuploid cells, including 3 of 9 villous and 4 of 10 villoglandular polyps with histologic features of carcinoma in situ (CIS), 4 of 11 villous and 1 of 18 villoglandular polyps without CIS, and 1 of 12 adenomatous polyps. Eight hyperplastic polyps were diploid. These results show retrospective FCM analysis can detect DNA aneuploidy in polyps; DNA aneuploidy may occur before histologic evidence of invasive carcinoma; and this change is more frequent in types of polyps thought to have increased malignant potential (i.e., those with villous morphology and/or CIS).

Adenoma↗
PubMed1987

Modulation of the metastatic phenotype by 13-cis-retinoic acid.

KLN 205 murine squamous carcinoma cells were grown in medium supplemented with the retinoid 13-cis-retinoic acid (RA) to study the relationship between RA-induced cell surface changes and alterations of the metastatic phenotype. Modulation of the cell surface glycoconjugate expression was measured by flow cytometric analysis of the RA-treated tumor cells stained with fluoresceinated lectins. RA treatment (5 X 10(-6) and 5 X 10(-7) M) altered the glycoconjugate expression of KLN 205 cells in a selective, dose-dependent fashion. Tumor cells grown in RA-supplemented medium for more than 4 days demonstrated greatly increased binding of fluoresceinated Griffonia simplicifolia I lectin, peanut lectin, wheat-germ lectin, concanavalin A, and soybean lectin (P less than .001), but the increased binding of Ulex europaeus lectin was of a much smaller magnitude (P = .02). After 15 days of growth in these noncytotoxic or cytostatic concentrations of RA, malignant KLN 205 cells had a greatly decreased proclivity to metastasize, as measured by the lung colony assay (P = .0003). The RA-induced cell surface glycoconjugate changes preceded the decrease in experimental metastatic potential. Since enzymatic (neuraminidase) alteration of the tumor cell surface to produce glycoconjugate expression similar to that seen in RA-treated cells also reduced the ability of the KLN 205 cells to form lung colonies (P = .0022), it is suggested that RA-induced alteration of the cell surface carbohydrate antigens is related to the decreased experimental metastatic potential seen in tumor cells treated with RA.

Animals↗
PubMed1986

Origin of multiple "primary" colon carcinomas. A retrospective flow cytometric study.

Multiple, synchronous, apparently primary carcinomas of the colon are a relatively common occurrence. The DNA ploidy in 23 colon carcinomas from 10 patients was determined to see if this parameter supported common or independent origins for such synchronous lesions. Paraffin blocks of each tumor were prepared for flow cytometry, then analyzed for nuclear DNA content. In 3 of the 10 cases, the tumors within each colon differed with respect to DNA ploidy; in four cases all tumors were diploid; and in three cases both (all) tumors within each colon had identical aneuploid DNA indices. Tumors from the same colon with identical DNA histograms often had dissimilar histology. The replicate aneuploid DNA indices strongly suggest a common origin for the multiple tumors within these colons; tumors in the other groups are compatible with either single or multiple origins. These findings suggest that multiple "primary" colon carcinomas may, in some cases, arise as translumenal metastases from an initial single lesion.

Adenocarcinoma↗
PubMed1986

Flow cytometric analysis of deparaffinized nuclei in urinary bladder carcinoma. Comparison with cytogenetic analysis.

Both cytogenetic analysis and flow cytometry (FCM) have prognostic efficacy in the analysis of transitional cell carcinoma (TCC) of urinary bladder. To correlate results of the two methods, we studied a unique group of patients whose tumors had undergone prospective conventional cytogenetic analysis. Paraffin blocks of these tumors were processed for FMC, then analyzed for nuclear DNA content. Of the 34 tumors processed, 30 (88%) yielded interpretable DNA histograms. In 26 (87%) of these, there was good correlation between the two methods with respect to the presence or absence of a hyperdiploid cell line. Discrepancies may have resulted from sampling error or from interpretation of a tetraploid peak as a prominent G2M region. Retrospective FCM analysis of paraffinized TCC tissue correlates well with conventional, prospective cytogenetic analysis and is applicable to the majority of urinary bladder transitional cell carcinomas.

Adult↗
PubMed1986

Retrospective DNA analysis of head and neck squamous cell carcinoma.

Abnormal cellular DNA content, a hallmark of malignancy, is known to occur in squamous cell carcinoma of the head and neck. The significance of this finding has yet to be elucidated. Paraffin-embedded blocks from 46 squamous cell carcinomas of the head and neck were sectioned, dewaxed, and made into a suspension of bare nuclei by mechanical mincing and enzymatic digestion. The nuclei were stained with propidium iodide, and quantitative DNA measurements were obtained with flow cytometry. The results were compared with existing prognostic factors: DNA aneuploidy was identified in 41% of the specimens and was significantly correlated with tumor size and surgical stage; the relationship between DNA aneuploidy and anatomic site approaches statistical significance. There was no correlation with histologic grade or presence or absence of cervical metastasis.

Aneuploidy↗