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K D Bauer

Publications and source records attributed to K D Bauer.

At least 37 records · Page 2Linked to original sources

Improved DNA content histograms from formalin-fixed, paraffin-embedded liver tissue by proteinase K digestion.

An improved method for the enzymatic digestion of formalin-fixed, paraffin-embedded liver tissue for DNA content analysis by flow cytometry is presented. Forty samples of histologically normal liver were alternately digested by the traditional pepsin method or a new method utilizing proteinase K and heat. Sixteen (40%) of the pepsin-digested samples had apparent DNA aneuploid peaks by flow cytometry. False DNA aneuploid peaks were not present in any of the histograms obtained after proteinase K digestion. Microscopy showed that the pepsin-digested samples had residual cytoplasmic remnants which contained fluorescent material. Samples digested with proteinase K had few cytoplasmic remnants. The average G0/G1 coefficient of variation after proteinase K treatment was lower (41%) and the fluorescent intensity higher (128%) than the pepsin-treated samples. The apparent mean S-phase (a combination of S-phase cells and underlying debris) after proteinase K digestion was 35% of the pepsin-treated samples. Primary and secondary tumors of the liver that were DNA aneuploid after pepsin treatment were also DNA aneuploid after proteinase K treatment. A modified digestion protocol utilizing proteinase K and heat can provide superior results for DNA content analysis of formalin-fixed, paraffin-embedded liver tissue.

Aneuploidy↗

DNA flow cytometric analysis of clinical stage I endometrial carcinomas with lymph node metastases.

Twenty-one (8%) of 264 consecutive evaluable patients with clinical stage 1 endometrial carcinoma had histologic evidence of pelvic and/or para-aortic lymph node metastases. DNA flow cytometry was performed on both the primary tumor and nodal metastasis. Seventeen of 21 sets could be analyzed. Overall, 11 (65%) of the primary carcinomas were aneuploid. Nine of 17 (53%) had consistent ploidy patterns when the primary tumor and lymphatic metastasis were compared. The remaining 8 (47%) had aneuploid primaries with diploid nodal metastases. Five (83%) of the 6 patients with diploid primary tumors were alive without evidence of disease compared to 3 of 11 (27%) patients with aneuploid tumors (P < 0.05). Other predictors of disease outcome included tumor histology, lymph vascular space invasion, and depth of myometrial invasion. Ploidy status of the lymphatic metastasis was not important in terms of overall survival. All 8 patients with para-aortic nodal metastases had aneuploid primary carcinomas compared to 4 (44%) of 9 patients with pelvic node involvement only (P < 0.01). Mean survival was 31 months for patients with para-aortic node metastases compared to 51 months for patients with only pelvic node metastases. Comparison of survival curves among these two groups demonstrated a significant survival advantage in patients with regional nodal metastases (P = 0.032). S-phase fraction of both the primary tumor and lymphatic metastasis did not correlate with survival or predict disease outcome. DNA index of the primary tumor, as a continuous variable, was inversely proportional to survival, demonstrating poorer survivorship with incremental increases of DI. Ploidy status of the lymph node metastasis was an inconsistent reflection of the primary tumor's expression and behavior and, therefore, little additional information was gained by knowledge of the lymphatic ploidy status.

Adult↗

Detection of c-erbB-2 oncoprotein expression in breast tissue by multiparameter flow cytometry.

A novel technique in multiparameter flow cytometry (FCM) using dual laser excitation of three fluorescent dyes has been developed to differentiate breast epithelial cells from stromal components. This technique has been applied to determine the expression of the oncoprotein c-erbB-2 in breast epithelial tumors. SK-BR-3, a breast cancer cell line with c-erbB-2 overexpression, can be identified by FCM from a mixed cell suspension using a monoclonal anti-human cytokeratin antibody conjugated with fluorescein isothiocyanate. Using the mouse monoclonal anti-c-erbB-2 antibody, TA-1 (4.8 +/- 1.0 x isotype control), the c-erbB-2 oncoprotein overexpression in breast epithelial cells can be detected as an increase in indirect blue fluorescence by aminomethyl coumarin. MCF-7, a breast cancer cell line with normal c-erbB-2 expression, has baseline blue fluorescence (1.0 +/- 0.5 x isotope control). Twenty-one fresh breast specimens have been examined by FCM. Overexpression of c-erbB-2, defined by blue fluorescence ratio of TA-1/isotype control > or = 1.5 (> 3 SD from baseline), is detected in 0 of 3 patients with Stage I cancer, 5 of 14 patients with Stage II and III cancer, and 3 of 4 patients with proliferative disease. Patients with elevation of oncoprotein detected by FCM have corresponding RNA overexpression detected by Northern blot hybridization and increased gene amplification detected by Southern blot hybridization. FCM allows for the simultaneous identification of breast epithelial cells and the selective examination of these cells for the expression of c-erbB-2 oncoprotein, thus minimizing stromal contamination. This represents a novel application of FCM with potential for wide clinical applicability.

Biomarkers, Tumor↗

DNA profile of nephrogenic adenoma assessed by flow cytometry.

Nephrogenic adenoma is a metaplastic condition which usually involves the bladder urothelium within the clinical setting of chronic inflammation. Its presentation/endoscopic appearance may mimic bladder cancer and a premalignant potential has been speculated. DNA flow cytometry performed on involved bladder tissue revealed a diploid phenotype exhibiting low proliferative activity. These findings are most suggestive of a benign process.

Adenoma↗

Effect of retinoic acid on the proliferation and secretory activity of androgen-responsive prostatic carcinoma cells.

We studied the effect of retinoic acid on the growth and secretory activity of the androgen-responsive prostatic carcinoma cell line LNCaP. Our data showed that retinoic acid at 0.01 microM. stimulated the proliferation of LNCaP cells but inhibited their growth at 0.1 microM. under androgen-free conditions. In the presence of 0.1 nM. dihydrotestosterone (DHT), LNCaP cell proliferation was inhibited by 10 microM. retinoic acid but not by lower concentrations of retinoic acid. Retinoic acid reduced LNCaP cell growth at concentrations of 0.1 microM. in the presence of 10 nM. DHT. Retinoic acid (10 microM.) also reduced the growth response of LNCaP cells to epidermal growth factor and transforming growth factor alpha and potentiated the inhibitory effect of transforming growth factor beta. In additional studies, retinoic acid induced a dose-dependent increase in prostate specific antigen (PSA) secretion at concentrations of 0.1 to 1 microM. Dihydrotestosterone (10 nM.) also enhanced the secretion of PSA by LNCaP cells, and this effect was potentiated in a dose-dependent fashion by the addition of retinoic acid at 0.1-10 microM. Competitive binding studies showed that retinoic acid did not bind to androgen receptors. Overall, retinoic acid had a biphasic effect on LNCaP proliferation and promoted the secretion of PSA. The biphasic effect of retinoic acid on LNCaP growth should be considered in designing in vivo studies to determine the impact of retinoic acid on solid prostatic tumor growth. In addition, the ability of retinoic acid to increase PSA secretion may complicate the interpretation of serum PSA levels used for diagnostic and prognostic purposes.

Androgens↗

Changes in T and non-T lymphocyte subsets following seroconversion to HIV-1: stable CD3+ and declining CD3- populations suggest regulatory responses linked to loss of CD4 lymphocytes. The Multicenter AIDS Cohort Study.

We investigated changes in lymphocyte subsets (total, CD4+ and CD8+ T cells, as well as non-T cells) associated with human immunodeficiency virus type I (HIV-1) seroconversion in 321 homosexual or bisexual men in the Multicenter AIDS Cohort Study (MACS). These subjects had serial lymphocyte characterizations for up to 4 years before and 5 years after seroconversion. CD4+ lymphocyte levels declined rapidly in the first 18 months following seroconversion and less rapidly thereafter, while CD8 lymphocytes increased with similar kinetics. In contrast, total T (CD3+) lymphocytes declined only slightly in the first 18 months following seroconversion, and then remained stable. These results support the hypothesis of physiologic regulation of the total number of circulating T cells, such that lost CD4+ lymphocytes are replaced by newly generated CD4+ and CD8+ lymphocytes; over time, continued loss of CD4+ lymphocytes due to HIV-1 infection would result in net replacement of lost CD4+ lymphocytes with CD8+ lymphocytes. Non-T (CD3-) lymphocytes also declined after seroconversion, and this decline paralleled that of CD4+ lymphocytes. Thus, changes in both T and non-T lymphocytes after HIV-1 seroconversion may reflect the operation of homeostatic or regulatory mechanisms. Whether these mechanisms contribute to the development of immune deficiency requires further study.

CD3 Complex↗

Flow cytometric evaluation of early invasive cervical cancer.

OBJECTIVE: To define the role of flow cytometry as a prognostic indicator in early cancers of the uterine cervix. METHODS: Flow cytometry was used to determine ploidy, DNA index, and S-phase fraction on 141 samples from the tumors of 53 women with stage IB cancers of the cervix treated by radical hysterectomy and pelvic lymphadenectomy as primary therapy. Multiple samples of the same tumor were analyzable for 47 (89%) of the subjects. One-way analysis of variance for the multiple samples was used to compare the heterogeneity of flow cytometry data, both within each tumor and between patients. Flow cytometry results, as well as previously described clinical and pathologic prognostic factors, were correlated to recurrence and survival using Cox regression hazard ratios and Kaplan-Meier estimates. RESULTS: We found DNA aneuploidy in 25 (47%) of the cancers, with a mean (+/- standard error) DNA index of 1.52 +/- 0.07. The mean S-phase fraction was 7.6 +/- 0.4% for diploid tumors and 9.2 +/- 0.4% for aneuploid tumors. The cancers from 24 women (45%) were homogeneously diploid, 18 (34%) were consistently aneuploid, and five (9%) had mixed diploid/aneuploid samples. Analysis of variance of the multiple samples for each woman revealed a greater standard deviation (SD) between patients than within any individual tumor for both DNA index (ratio of between SD to within SD 2.1; P < .0001) and S-phase fraction (ratio 1.6; P < .0001). Of the previously described clinical and pathologic prognostic factors, only depth of invasion, expressed as either percent of cervical wall thickness or as thirds, was correlated with recurrence or survival. Neither the DNA index nor S-phase fraction correlated significantly with recurrence or survival. CONCLUSIONS: These results suggest that alterations in the DNA content or proliferative activity of early invasive cancers of the uterine cervix do not reflect biologic behavior in terms of recurrence or survival, and that this behavior is not due to tumor heterogeneity.

Adenocarcinoma↗

Diagnostic utility of DNA content flow cytometry in follicular neoplasms of the thyroid.

Preoperative diagnosis of follicular carcinoma of the thyroid remains a clinical challenge. This study determined the DNA content parameters of ploidy and proliferative activity levels from cells of normal thyroid tissue, follicular adenomas, and follicular carcinomas to evaluate if these parameters could be used as an adjunct to fine needle aspiration in their diagnosis. Statistically significant higher proliferative activity levels were found in the carcinoma groups (mean S-phase fraction [SPF] = 5.0%) compared to 2.9% for follicular adenomas and 1.3% for normal thyroid. DNA aneuploidy was identified in 73% of carcinomas and 36% of adenomas. Because of overlap of SPF values between groups, one could not rule out the presence or absence of malignancy based on DNA content parameters alone. These measurements may, however, be an aid to the decision making in patients who are poor surgical risks.

Adenocarcinoma↗

Flow cytometric analysis of small renal tumors.

Flow cytometric deoxyribonucleic acid (DNA) content analysis was performed on 26 renal tumors 3.0 cm. or less in maximum diameter. We noted DNA aneuploid cell populations in 8 of 25 tumors (32%) evaluable for DNA ploidy status. DNA aneuploid cells comprised 7 to 59% of the cells in those tumors. In comparison, 12 of 25 tumors (48%) larger than 3.0 cm. had aneuploid cell populations. S phase cell populations were significantly increased in the small aneuploid tumors compared with the small diploid tumors (p < 0.001). We believe that these small tumors have the potential to behave aggressively and, therefore, they should be treated no differently than larger renal neoplasms.

Adult↗

Prognostic implications of proliferative activity and DNA aneuploidy in Astler-Coller Dukes stage C colonic adenocarcinomas.

Paraffin-embedded surgical specimens from 69 patients who underwent resections of otherwise untreated Dukes stage C adenocarcinoma of the colon were examined for proliferative activity, DNA aneuploidy, DNA index, and proportion of aneuploid cells by flow cytometry. Results were correlated to clinical characteristics of the patients and to overall survival times. DNA aneuploid tumors were identified in 60 cases (87%), diploid tumors in 9 cases (13%). The mean S-phase fraction for all cases was 17.6%, with a standard deviation (SD) of 7.8. In univariate statistical analysis, younger patient age, lower tumor proliferative activity, DNA index less than or equal to 1.2, and presence of only 1-4 lymph nodes with tumor involvement were found to be significant predictors of improved patient survival. In multivariate Cox regression analysis, low tumor proliferative activity, younger patient age, and location of the tumor in the right or transverse colon were found to be significant independent predictors of increased patient survival. When tumor proliferative activity was stratified into statistically defined subgroups, patients with tumors of low proliferative activity (S-phase less than mean - 0.5 SD) had significantly longer survival than patients with tumors of moderate proliferative activity (S-phase value greater than mean - 0.5 SD and less than mean +0.5 SD) or high proliferative activity (S-phase greater than mean +0.5 SD). These results suggest that tumor proliferative activity in Dukes C colon carcinoma may be an important biological factor in determining patient prognosis.

Adenocarcinoma↗

Simultaneous quantification of c-myc oncoprotein, total cellular protein, and DNA content using multiparameter flow cytometry.

Variations in total cellular protein content can confound interpretation of the significance of modulations of specific cellular proteins. In an effort to overcome this problem, a technique is described for the simultaneous measurement of a specific cellular protein, total cellular protein, and DNA content. The method utilizes dual-laser (uv and 488 nm) excitation and three fluorescent dyes: FITC, SR101, and DAPI. FITC-labelled antibody coupled with indirect immunofluorescence was used to quantify the c-myc oncoprotein, whereas SR101 and DAPI were used to measure total cellular protein and cellular DNA, respectively. Flow cytometric measurements of c-myc oncoprotein were compared to densitometric readings of p64c-myc. SR101 protein determinations were compared to those obtained by the Lowry technique. Results indicated that flow cytometric measurements correlated well with those obtained by the biochemical methods. The usefulness of the technique was further examined following treatment of exponentially growing HL-60 cells with 2.5 micrograms/ml cycloheximide for 0 to 12 h. Cycloheximide treatment was found to cause a significant decrease in c-myc oncoprotein content within 2 h (P less than 0.05), a relative increase in the proportion of G0/G1 cells and a modest decrease in total cellular protein. This technique appears to provide a rapid, quantitative approach, useful for investigating alterations in cellular growth balance occurring with cell differentiation, neoplastic transformation, or cell treatment with radiation or cytostatic drugs.

Cell Cycle↗

Heterogeneity in plasminogen activator (PA) levels in human prostate cancer cell lines: increased PA activity correlates with biologically aggressive behavior.

Plasminogen activators (PA), particularly the lower Mr urokinase (u-PA) type, have been associated with tumor cell invasion and metastasis. We have examined the expression of PA by two human prostate cancer cell lines (PC-3 and DU-145) using functional and immunologic techniques. The culture media and cell extracts of the more aggressive PC-3 cell line contained more than two-fold greater PA activity than the relatively indolent DU-145 cell line. Zymographic studies identified the PA expressed as u-PA. PC-3 cells expressed an additional lower molecular weight form of u-PA not noted in DU-145 cells. Heterogeneity in u-PA expression was shown by the fibrin lysis assay, immunohistochemistry, and dual parameter flow cytometry indicating the presence of phenotypically divergent cell populations. Increased u-PA expression may identify those tumor cells that possess aggressive biological potential.

Flow Cytometry↗

Reconstituted basement membrane promotes morphological and functional differentiation of primary human prostatic epithelial cells.

Prostatic epithelial cells undergo rapid proliferation and lose their ability to synthesize and secrete prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) under standard tissue culture conditions. Herein, we compared the morphology, growth, secretory activity, and intermediate filament expression of human prostatic epithelial cells cultured on either standard tissue culture plastic or reconstituted basement membrane. Epithelial cells grown on plastic exhibited a 10-fold increase in proliferation and a higher percentage of cells in the S-phase of the cell cycle compared to cells cultured on basement membrane. However, cells grown on basement membrane secreted markedly higher levels of PSA and PAP. The basement membrane-induced enhancement of secretory activity was potentiated by dihydrotestosterone (DHT) and prostate stromal cell conditioned medium. Morphological studies showed that cells plated on basement membrane formed organoid-like clusters and maintained several aspects of differentiated epithelium including abundant secretory vesicles, microvilli, and desmosomes with associated cytoskeletal elements. Cultivation of epithelial cells on basement membrane components also suppressed the expression of vimentin, a mesenchymal intermediate filament polypeptide. However, cytokeratin expression was abnormal in cells grown on either surface. These results indicate that the differentiated properties of prostatic epithelial cells are promoted by cultivation on reconstituted basement membrane in the presence of DHT and stromal cell conditioned medium.

Acid Phosphatase↗

Changes in cell nuclei during S phase: progressive chromatin condensation and altered expression of the proliferation-associated nuclear proteins Ki-67, cyclin (PCNA), p105, and p34.

Using multiparameter flow cytometry we have measured the nuclear DNA content of exponentially growing HL-60 cells in conjunction with protein content, nuclear forward light scatter, DNA in situ sensitivity to denaturation, DNA accessibility to 7-aminoactinomycin D (7-AMD), and content of the proliferation-associated proteins: cyclin (PCNA), p105, p34, and Ki-67. Multivariate analysis of the data made it possible to correlate changes in each parameter with the degree of cell advancement through S phase (amount of replicated DNA). A decrease of the protein/DNA ratio, lowered DNA accessibility to 7-AMD, increased sensitivity of DNA to denaturation, and increased ability of isolated nuclei to scatter light all paralleled cell progression through S phase. These changes indicate that during S phase chromatin progressively condenses and suggest that the condensation is associated with the efflux of nonhistone proteins from the nucleus. The increase in the content of the antigen detected by the Ki-67 antibody was observed to exceed the increase in DNA content during S phase and the rate of the Ki-67/DNA increase was higher during the second half of S phase. Thus, this protein appears to be primarily synthesized during S, especially late in S phase, and is degraded in G1. The ratio of cyclin (PCNA)/DNA remained rather constant whereas the contents of p105 and p34 proteins, when expressed per unit of DNA, both decreased during S phase. The data indicate that significant changes in structure and composition of chromatin take place during S phase and suggest that the composition of chromatin associated with the nonreplicated DNA is different compared to chromatin associated with the newly replicated DNA.

Cell Division↗

Human immunodeficiency virus-related lymphomas: a possible association between tumor proliferation, lack of ploidy anomalies, and immune deficiency.

In an attempt to identify a biologic basis for the aggressive clinical behavior of human immunodeficiency virus (HIV)-associated lymphomas (HAL), dual-parameter flow-cytometric analysis was performed on 22 paraffin-embedded biopsy specimens. Cases were analyzed for DNA ploidy, the percentage of cells in S-phase (proliferative activity), and content of a recently identified proliferation-associated nuclear antigen, p105. The DNA-content analysis of 22 HALs was compared with that of 109 cases of intermediate-grade non-Hodgkin's lymphoma (NHL) unrelated to the acquired immune deficiency syndrome (AIDS) studied previously in our laboratory and 125 cases of high-grade NHL reported in the literature. The proliferative activity was higher in intermediate-grade HAL relative to non-AIDS NHL (24.0% v 10.4%; P = .03), and in high-grade HAL in comparison with NHLs of similar histology unassociated with HIV infection (24.8% v 19%), although the latter did not reach statistical significance. The number of mitoses per 10 high-power fields was found to correlate with the percentage of cells in S-phase (r = .68; P = .0004). Although p105 content tended to be higher in HAL than in an AIDS-related complex (ARC)-associated hyperplastic lymph node control, no statistically significant associations were found between p105 content and proliferative activity or the number of mitoses per 10 high-power fields. When compared with non-AIDS NHLs of comparable grade, there was a trend toward a lower incidence of DNA aneuploidy in both intermediate- (25% v 56%) and high-grade (38.5% v 60%) HALs. The higher proliferative activity and lower incidence of DNA aneuploidy found in HAL relative to non-AIDS NHL of comparable histologic grade may represent differences in pathogenesis and may underlie the poor prognosis of HIV-associated NHL.

Adult↗

Dual-parameter flow cytometric analysis coupling the measurements of forward-angle light scatter and DNA content of archival ovarian carcinomas of low malignant potential.

Paraffin-embedded archival specimens from 45 cases of ovarian carcinoma of low malignant potential (OCLMP) were analyzed by flow cytometry (FCM) using propidium iodide (PI) staining. Since single-parameter FCM analysis is often deficient in the resolution of subtle near-diploid DNA-aneuploid populations, forward-angle light scatter (FALS) was measured as a second parameter. DNA aneuploidy was identified in 15 cases (33%). In 7 of those 15 cases, aneuploidy was resolved with single-parameter FCM; in the remaining 8 cases, DNA aneuploidy was resolved only following dual-parameter analysis coupling DNA content and FALS. In all 15 cases, a single near-diploid aneuploid population was observed (mean DNA index = 1.2); there were no tetraploid aneuploid cases. The proliferative activity for all 45 cases studied ranged from 1.0% to 8.9%, with a mean of 3.5%. No difference in mean proliferative activity was observed between the aneuploid and diploid tumors (P greater than .05). To exclude the possibility that PI staining artifacts caused the observed aneuploidy, five of the eight cases shown to be aneuploid by dual-parameter analysis were further studied using an alternate DNA-binding dye, DAPI, yielding similar results. To exclude the possibility that contaminating stromal and/or inflammatory cells caused the observed aneuploidy, samples from a subset of the dual-parameter cases were sorted, revealing the aneuploid populations to be composed primarily of tumor nuclei.(ABSTRACT TRUNCATED AT 250 WORDS)

Aneuploidy↗