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Query: UMLS:C0006142 (breast cancer)
 160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoclonal anti-proliferating cell nuclear antigen (PCNA PC10), which is directed against a 36 kDa auxiliary protein for DNA polymerase delta specific for the S-phase of cell cycle, was used to measure tumour cell proliferation in 4 lactating breasts and 98 benign and malignant breast tumours. The percentage of PCNA-positive cells determined by point counting was significantly lower in the lactating breast [mean 3.6%, standard deviation (SD) 0.67, n = 5] than in fibroadenoma and mastopathy (mean 23.7, SD 5.0, n = 2). Primary breast carcinoma showed a PCNA index ranging from 2% to 36% (mean 12.3, SD 9.3, n = 50), whereas in recurrent carcinoma the index was mean 28.5, SD 4.0. A high index was correlated with c-erbB-2 and epidermal growth factor (EGF) receptor membrane reactivity, worsening histological grade, poor survival and disease-free survival. The expression of c-erbB-2 and EGF receptor was associated with poor survival and disease-free survival in primary breast cancer patients.
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PMID:Proliferating cell nuclear antigen in breast lesions: correlation of c-erbB-2 oncoprotein and EGF receptor and its clinicopathological significance in breast cancer. 135 12

The proliferative activity in 42 cases of breast cancer were assessed immunohistochemically using antibodies to proliferating cell nuclear antigen (PCNA) and Ki-67. These indices were correlated with the steroid receptor status, pathologic stage, and disease-free survival. There was a strong direct correlation between the two proliferation indices (r = .902, P < 0.001, Kendall's rank correlation). There was a weak correlation between the hormone receptor status and proliferation indices that was not significant when statistically tested. The cases were stratified into PCNA low proliferative index (PI) group (< 4.5% positive cells) and PCNA high PI group (> 4.5% positive cells). In the low PI group, five of 18 (28%) patients were node-positive in contrast to eight of 14 (58%) patients in the high PI group. After a follow-up period of 42-60 months, 14 of 19 (74%) patients in the low PI group were disease-free compared to 10 of 17 (53%) patients in the high PI group. The PCNA and Ki-67 proliferative indices appear to be of great prognostic value and may help identify a subset of breast cancer patients who should be given adjuvant therapy.
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PMID:Correlation of proliferative index (PCNA reactivity and Ki-67 reactivity) in primary breast carcinoma with hormone status, lymph node status, and disease-free survival. 136 23

The PC-10 monoclonal antibody to PCNA was employed to analyze proliferative grade in conventionally-formalin fixed, paraffin-embedded tumour samples of 162 patients with primary breast carcinoma. To perform the immunocytochemical method, sections were not heated, were de-waxed using alcohol, and then immersed in a phosphate-buffered saline solution and in methanol with 0.5% hydrogen peroxide to block endogenous peroxidase activity. Immunostaining was performed by a streptavidin-biotin peroxidase substrate. A semiquantitative scoring system was used to evaluate the fraction of nuclei that were PCNA-positive. The score ranged from 0% to 75% with a median value of 25%, mean of 27.8 +/- 1.5. PCNA staining was significantly associated with oestrogen receptor-negativity (p = 0.011) and correlated, but not at a statistically significant level, with tumour size (p = 0.08). No significant association was observed between PCNA and node status, grading, DNA ploidy, progesterone receptor or menopausal status. Prognostic indices such as number of positive lymph nodes and DNA ploidy were significantly associated with relapse-free survival (RFS) and overall survival (OS). No significant correlation between PCNA nuclear immunostaining and RFS or OS was observed after a median follow-up of 4 years. Our results indicate that analysis of PCNA alone does not seem to be a useful marker in identifying patients at different prognosis in human breast cancer.
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PMID:PC-10 antibody to proliferating cell nuclear antigen (PCNA) is not related to prognosis in human breast carcinoma. 136 82

Monoclonal antibodies (MAbs) to nuclear antigens are increasingly used as tools to obtain valuable information concerning the proliferative characteristics of various types of cancer. Prerequisite for the application of these MAbs in surgical pathology is establishment of the level of expression and/or cellular distribution of the antigens in relation to distinct cell-cycle compartments. In this study the topologic distribution of proliferating cell nuclear antigen (PCNA), an auxiliary protein of DNA polymerase delta, as recognized by human autoantiserum (AK) and two recently developed MAbs (19A2 and 19F4), was evaluated. Using cultured human cancer cells as a model system, and providing optimal fixation/permeation procedures are applied, these antibodies display a high affinity for PCNA bound to nuclear replicon clusters, resulting in distinct granular staining patterns. A more diffuse nucleoplasmic PCNA staining was mainly restricted to non-S-phase cells; in methanol-fixed cells, staining intensity of this form relative to the replicon-bound form appeared higher after staining with 19A2 than with 19F4 or AK. Comparing PCNA expression (detected with 19A2) with the expression of the Ki-67 antigen, PCNA-negative cells are also Ki-67 negative. In MCF-7 human breast cancer cells treated with 10(-6) mol/l (molar) tamoxifen, the fraction of nuclei showing replication patterns decreased from 42% to 8% within 8 days, but PCNA and Ki-67 antigens remained detectable in most cells during this interval, indicating a relatively slow decrease of antigen expression in cells that have entered a quiescent state. Treatment of MCF-7 cells with 10(-6) mol/l methotrexate resulted in a rapid accumulation of cells with an early S-phase DNA content; PCNA replication patterns showing a frequency distribution reflecting this DNA content were observed up to 48 hours after treatment. This indicates that the presence of replication patterns as visualized with anti-PCNAs is not a measure of replicative activity per se. It is concluded that, providing nuclear non-S-phase PCNA staining is faint relative to staining of replicon clusters, anti-PCNA antibodies may be excellent markers to detect in situ cells with S-phase DNA contents.
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PMID:Cell-cycle-related staining patterns of anti-proliferating cell nuclear antigen monoclonal antibodies. Comparison with BrdUrd labeling and Ki-67 staining. 167 21

The MDA-468 human breast cancer cell line displays the unusual phenomenon of growth inhibition in response to pharmacological concentrations of EGF. This study was initiated with the objective of elucidating the cellular mechanisms involved in EGF-induced growth inhibition. Following EGF treatment the percentage of MDA-468 cells in G1 phase increased, together with a concomitant depletion in S and G2/M phase populations, as revealed by flow cytometry of DNA content. The apparent G1 block in the cell cycle was confirmed by treating the cells with vinblastine. DNA synthesis was reduced to about 35% of that measured in control, untreated cells after 48 h of EGF treatment, as measured by the incorporation of [3H]thymidine. DNA synthesis returned to normal following the removal of EGF from the growth-arrested cells. In order to locate the EGF-induced event responsible for the G1 arrest more precisely, we examined the expression of certain cell cycle-dependent genes by Northern blot analysis. EGF treatment did not alter either the induction of the early G1 marker, c-myc, or the expression of the late G1 markers, proliferating cell nuclear antigen, and thymidine kinase. However, EGF-treated cells revealed down regulation of p53 and histone 3.2 expression, which are expressed at the G1/S boundary and in S phase, respectively. These results indicate that EGF-induced growth inhibition in MDA-468 human breast cancer cells is characterized by a reversible cell cycle block at the G1/S boundary.
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PMID:EGF-dependent growth inhibition in MDA-468 human breast cancer cells is characterized by late G1 arrest and altered gene expression. 167 99

Although tumor DNA content and proliferation are usually determined by flow cytometry (FCM), quantitative microscopic image analysis is a viable alternative technique that also provides important histologic correlations. To compare these methods, we measured DNA content and proliferation in 54 consecutive breast cancers and 15 benign breast lesions by FCM and IA. DNA content determination was concordant in 49 of 54 cancers measured by FCM and IA. Four of the discordant cases were aneuploid by IA and diploid by FCM. There was good correlation between the DNA index (DI) measured by FCM and IA (r = 0.89, P less than 0.0001). Proliferation was assessed by IA quantitation of Ki-67 and PCNA/Cyclin antibody staining, as well as by flow cytometric S-phase fraction (SPF). Ki-67 positivity was greater in breast cancer than in benign controls (21.6% +/- 13.1% vs. 7.9% +/- 5.6% [P less than 0.0001]), as was PCNA/Cyclin positivity (10.2 +/- 6.7% vs. 2.7 +/- 2.5% [P less than 0.0001]). S-phase fraction measured by FCM was 7.9% +/- 5.7% for carcinomas and 3.17% +/- 2.1% for benign controls (P less than 0.003). Ki-67 and Cyclin staining, as well as SPF, were significantly increased in aneuploid compared to diploid tumors, and increased staining was associated with worsening nuclear grade. There were significant correlations between SPF and Ki-67 staining (r = 0.48, P less than 0.0001) and SPF and Cyclin staining (r = 0.48, P less than 0.0001). We conclude that FCM and IA provide comparable measurements of DNA content, although occasional discrepancies occur. Image analysis provides a valuable alternative method for assessing tumor cell proliferation and may offer certain advantages over FCM.
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PMID:Comparative assessment of proliferation and DNA content in breast carcinoma by image analysis and flow cytometry. 197

The proliferative activity of male breast carcinoma has been investigated using the staining of the argyrophilic nucleolar organizer regions (AgNORs), the monoclonal antibody against the proliferating cell nuclear antigen (PC10) and the monoclonal antibody MIB-1 in formalin-fixed, paraffin-embedded specimens from 27 primary male breast carcinomas at diagnosis. A significant correlation was found between survival and AgNOR counts (median of survival 77 months for cases with AgNOR/cell < or = 7.27 but 37 months only for cases with > 7.27 AgNOR/cell; P = 0.001), proliferating cell nuclear antigen scores (median of survival 73 months for cases with proliferating cell nuclear antigen < or = 18.25% versus 41 for cases with proliferating cell nuclear antigen > 18.25%; P = 0.013) and MIB-1 scores (median of survival 73 months for cases with MIB-1 scores < or = 23.5% versus 37 months for cases with MIB-1 scores > 23.5%; P = 0.01). Tumor histological grade was also correlated with prognosis (median of survival 72 months for grade 2 versus 33 months for grade 3 tumors; P = 0.01). Estrogen and progesterone receptors, immunohistochemically detected on paraffin-embedded sections, had no prognostic value. In the multivariate survival analysis, only AgNOR counts (P = 0.007) and tumor size (P = 0.003) had an independent prognostic significance. Our results indicate that methods for assessing the cell proliferation in routinely processed specimens offer significant prognostic information in male breast carcinoma. The finding, together with the lack of prognostic significance for estrogen receptors and progesterone receptors, suggests that male breast carcinoma is biologically different from female breast cancer.
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PMID:Proliferative activity is a significant prognostic factor in male breast carcinoma. 751 30

A series of 71 patients undergoing surgery for primary breast carcinoma was prospectively studied in order to evaluate the relative weight for four biologic factors (intermediate filament vimentin expression, proliferating cell nuclear antigen [PCNA], flow cytometric DNA ploidy and S-phase fraction) and of several clinicopathologic and biologic features in predicting clinical outcome (disease-free interval). In univariate statistical analysis, positivity of axillary nodes, high number of mitoses, high nuclear grade, high histologic grade, positivity of vimentin, high flow cytometric S-phase fraction (FCM-S) value, high PCNA and high silver-stained nuclear organizer regions scores were significantly related to risk of relapse. In multivariate analysis (Cox's logistic regression) only histologic grade (3) and high FCM-S values (> 10.7) were independently related to risk of relapse, with hazard ratios of 9.84 and 7.98, respectively. The results of our preliminary, prospective study suggest that FCM-S, in addition to morphologic criteria (histologic grade), may be an important biologic indicator in determining breast cancer patients' prognosis.
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PMID:Vimentin expression, proliferating cell nuclear antigen and flow cytometric factors. Prognostic role in breast cancer. 753 Sep 59

Dysregulation of cyclin expression has been reported for several human malignancies, including breast cancer. To further investigate the role of cyclin genes in mammary tumorigenesis we analyzed the expression of cyclins D1, E and A and other cell cycle-related proteins in a series of nine N-methyl-N-nitrosourea-induced primary rat mammary tumors. Western blot analysis revealed a 10- to 15-fold increase in the level of cyclin D1 protein in most (7/9) of the tumors, when compared with normal rat mammary gland. The two tumors that did not show this increase also displayed negligible levels of the retinoblastoma protein. A moderate increase, 1.5- to 2-fold, in the level of cyclin E was observed in four tumors and three tumors displayed abnormal low molecular weight cyclin E-related proteins. None of the tumors showed amplification of the cyclin D1 or E genes when studied by Southern blot analysis. All nine tumors showed a 2- to 6-fold increase in the level of cyclin A protein. Most of the tumors also displayed a marked increase in levels of the CDK2 and CDK4 proteins. These changes did not appear to be simply a consequence of increased cell proliferation, as assessed by proliferating cell nuclear antigen analysis. Thus, aberrant expression of cyclins and other cyclin-related genes occurs frequently in mammary tumorigenesis in both rodents and humans.
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PMID:Deregulated expression of cyclin D1 and other cell cycle-related genes in carcinogen-induced rat mammary tumors. 755 74

This paper reports on quantitative in situ changes in chromatin structure that occur throughout the cell cycle of the human breast cancer epithelial cell line, MCF-7. Texture parameters were measured by image cytometry on nuclei stained by DNA specific fluorochromes. These parameters calculated from the co-occurrence and run length matrices of grey level images were previously shown to be related to condensation, organization and distribution of DNA. In some experiments, cells were triple stained for DNA/Ki-67/PCNA, and compartmentalization in the cycle was ascertained from the Ki-67/PCNA pattern expression. In these experiments, Hoechst dye was used to stain DNA. Chromatin of cells traversing G1 phase progressively decondensed and became homogeneously distributed. In addition, these G1 cells had more condensed chromatin than cells in G0 phase (as determined by Ki-67 negative staining). During the S and G2 phases, chromatin condensation took place and an increasing reticulated organization was quantified. Similar profile of changes in chromatin texture was found in experiments done with cells double stained by AT-specific Hoechst dye and the GC-specific mithramycin dye. GC-rich chromatin texture-associated parameters greatly varied comparing to those of AT-rich chromatin during the G0/G1 phase as well as in the first mid-S phase. Conversely, variation of the AT-associated parameters was much greater in the second half of S phase as compared to the GC-associated parameters that barely varied during this period. This study well establishes the correlation between in situ chromatin texture and proliferation state because the latter is assessed by proliferation-associated antigens. Moreover, changes in chromatin texture are independently ascribed to the AT- and GC-rich regions suggesting that these 2 types of chromatin are involved to different extents in transcriptional and replicational tasks.
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PMID:Fluorescence image analysis of the MCF-7 cycle related changes in chromatin texture. Differences between AT- and GC-rich chromatin. 757 51


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