scholarly journals Apoptotic Cell Death and the Proliferative Capacity of Human Breast Cancers

1998 ◽  
Vol 16 (1) ◽  
pp. 1-10 ◽  
Author(s):  
Gabriele A. Losa ◽  
Riccardo Graber
Keyword(s):  
Cell Death ◽  
Dna Fragmentation ◽  
Apoptotic Cell ◽  
Steroid Hormone ◽  
S Phase ◽  
Phase Fraction ◽  
Breast Cancers ◽  
Proliferative Capacity ◽  
Human Breast ◽  
Dna Index

The proliferative capacity (%S‐phase fraction), DNA ploidy, apoptosis frequency (DNA fragmentation) and steroid hormone receptor status (estrogen receptor, ER; progesterone receptor, PR) of 110 samples of human breast tissues with ductal invasive carcinoma were measured using biochemical and cytofluorimetric procedures. The DNA fragmentation had a left‐skewed frequency distribution and an overall median value of 1.64%, whilst the median %S‐phase fraction was 8%. The median %DNA fragmentation and %S‐phase fraction were 1.96% and 16% in hyperdiploid tumours (n=29; DNA index >1.1) higher than in hypodiploid tumors (n=10; DNA index 0.96), 0.38% and 7.5%. DNA diploid tumours (n=71) had median %DNA fragmentation and %S‐phase values of 1.68% and 6%, consistently lower than the median values of DNA hyperdiploid tumours. The ER content of hypodiploid tumours was about one half (median: 5.9 fmol/mg) the median values in hyperdiploid (10.6 fmol/mg) and diploid tumours (14.6 fmol/mg). This may correlate with the lowest frequency of apoptosis in hypodiploid tumours, at least when measured by biochemical methods which only detect cells in the late phases of apoptosis. In contrast, the median PR was lowest in hyperdiploid tumours than in hypo and/or diploid tumours. The %S‐phase/%fragmented DNA ratio for the hypodiploid tumours was 19.7, significantly higher than the ratios for hyperdiploid (8.2) and diploid tumours (3.6). These findings indicated that there is an imbalance between proliferative capacity and cell death or growth arrest in human breast tumours. This imbalance may well be linked to a loss of steroid hormone control.

scholarly journals Intratumoral Variations in DNA Ploidy and S-Phase Fraction in Human Breast Cancer

2001 ◽  
Vol 23 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Conny Arnerlöv ◽  
Stefan O. Emdin ◽  
Stefan Cajander ◽  
Nils‐Olof Bengtsson ◽  
Björn Tavelin ◽  
...  
Keyword(s):  
Human Breast Cancer ◽  
Dna Ploidy ◽  
S Phase ◽  
Phase Fraction ◽  
Prognostic Indicators ◽  
Intratumor Heterogeneity ◽  
Breast Carcinomas ◽  
Human Breast ◽  
Dna Index ◽  
Aneuploidy Rate

To study intratumoral DNA ploidy heterogeneity and S‐phase fraction (SPF) variability, we prospectively collected five different samples from 48 breast carcinomas and each sample was analysed separately by flow cytometry. Aneuploidy rate was 89.6% after analysis of four or five samples. DNA ploidy heterogeneity, i.e., different samples classified as either DNA euploid or DNA aneuploid in the same tumor was seen in 17%, and DNA index heterogeneity, i.e., tumor populations with different DNA indices (DIs) seen in different samples was 44%. A statistical model defining SPF heterogeneity is proposed. SPF heterogeneity as defined by us was 71%, and as expected the SPF heterogeneity rate increased significantly with increasing number of analysed samples. Four or more samples are needed to detect the most deviant (highest) SPF values. An unrecognized intratumor heterogeneity of DNA ploidy and SPF may partly explain the conflicting results reported in the literature on the above prognostic indicators.

Sulindac induces apoptotic cell death in susceptible human breast cancer cells through, at least in part, inhibition of IKKβ

APOPTOSIS ◽  
2009 ◽  
Vol 14 (7) ◽  
pp. 913-922 ◽  
Author(s):  
A-Mi Seo ◽  
Seung-Woo Hong ◽  
Jae-Sik Shin ◽  
In-Chul Park ◽  
Nam-Joo Hong ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Human Breast Cancer Cells ◽  
Human Breast

Redistribution of phosphatidylethanolamine and phosphatidylserine precedes reperfusion-induced apoptosis

1998 ◽  
Vol 274 (1) ◽  
pp. H242-H248 ◽  
Author(s):  
Nilanjana Maulik ◽  
Valerian E. Kagan ◽  
Vladimir A. Tyurin ◽  
Dipak K. Das
Keyword(s):  
Cell Death ◽  
Dna Fragmentation ◽  
Genomic Dna ◽  
High Performance ◽  
Apoptotic Cell ◽  
Ischemia Reperfusion ◽  
Apoptotic Cell Death ◽  
Dna Laddering ◽  
Outer Leaflet ◽  
Induced Apoptosis

Although cardiomyocyte death and infarction associated with ischemia-reperfusion are traditionally believed to be induced via necrosis, recent studies implicated apoptotic cell death in ischemic reperfused tissue. To examine whether myocardial ischemic reperfusion injury is mediated by apoptotic cell death, isolated perfused rat hearts were subjected to 15 and 30 min of ischemia as well as 15 min of ischemia followed by 30, 90, or 120 min of reperfusion. At the end of each experiment, hearts were processed for the evaluation of apoptosis and DNA laddering. Apoptosis was studied by visualizing the apoptotic cardiomyocytes by direct fluorescence detection of digoxigenin-labeled genomic DNA using APOPTAG in situ apoptosis detection kit. DNA laddering was evaluated by subjecting the DNA obtained from cardiomyocytes to 1.8% agarose gel electrophoresis and photographed under ultraviolet illumination. In addition, high-performance thin-layer chromatography (HPTLC) of aminophospholipids labeled with 2,4,6-trinitrobenzenesulfonate was performed to evaluate phospholipid topography in cardiomyocytes. The results of our study revealed apoptotic cells only in the 90- and 120-min reperfused hearts as demonstrated by the intense fluorescence of the immunostained digoxigenin-labeled genomic DNA when observed under fluorescence microscope. None of the ischemic hearts showed any evidence of apoptosis. These results corroborated with the findings of DNA fragmentation that showed increased ladders of DNA bands in the 120-min reperfused hearts, representing integer multiples of the internucleosomal DNA length (∼180 bp). Two-dimensional HPTLC of the phospholipids obtained from the cardiomyocytes and transbilayer organization of the phosphatidylethanolamine (PE) and phosphatidylserine (PS) in the myocytes indicated translocation of both PE and PS from the inner leaflet to the outer leaflet of the membrane as early as after 20 min of ischemia. These results demonstrate that the redistribution of PS and PE precedes the apototic cell death and DNA fragmentation associated with the reperfusion of ischemic myocardium, suggesting that ischemia may trigger the signal for apoptosis although it becomes evident during reperfusion.

scholarly journals HDAC3–ERα Selectively Regulates TNF-α-Induced Apoptotic Cell Death in MCF-7 Human Breast Cancer Cells via the p53 Signaling Pathway

Cells ◽  
2020 ◽  
Vol 9 (5) ◽  
pp. 1280
Author(s):  
Seung-Ho Park ◽  
Hyunhee Kim ◽  
Sungmin Kwak ◽  
Ji-Hoon Jeong ◽  
Jangho Lee ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Death ◽  
Cancer Cells ◽  
Human Breast Cancer ◽  
Breast Cancer Cells ◽  
Apoptotic Cell ◽  
Human Breast Cancer Cells ◽  
Human Breast ◽  
Tnf Α ◽  
Mcf 7

Tumor necrosis factor-α (TNF-α) plays a significant role in inflammation and cancer-related apoptosis. We identified a TNF-α-mediated epigenetic mechanism of apoptotic cell death regulation in estrogen receptor-α (ERα)-positive human breast cancer cells. To assess the apoptotic effect of TNF-α, annexin V/ propidium iodide (PI) double staining, cell viability assays, and Western blotting were performed. To elucidate this mechanism, histone deacetylase (HDAC) activity assay and immunoprecipitation (IP) were conducted; the mechanism was subsequently confirmed through chromatin IP (ChIP) assays. Finally, we assessed HDAC3–ERα-mediated apoptotic cell death after TNF-α treatment in ERα-positive human breast cancer (MCF-7) cells via the transcriptional activation of p53 target genes using luciferase assay and quantitative reverse transcription PCR. The TNF-α-induced selective apoptosis in MCF-7 cells was negatively regulated by the HDAC3–ERα complex in a caspase-7-dependent manner. HDAC3 possessed a p53-binding element, thus suppressing the transcriptional activity of its target genes. In contrast, MCF-7 cell treatment with TNF-α led to dissociation of the HDAC3–ERα complex and substitution of the occupancy on the promoter by the p53–p300 complex, thus accelerating p53 target gene expression. In this process, p53 stabilization was accompanied by its acetylation. This study showed that p53-mediated apoptosis in ERα-positive human breast cancer cells was negatively regulated by HDAC3–ERα in a caspase-7-dependent manner. Therefore, these proteins have potential application in therapeutic strategies.

Molecular characterization of rabbit CPP32 and its function in vascular smooth muscle cell apoptosis

1998 ◽  
Vol 274 (4) ◽  
pp. H1132-H1140 ◽  
Author(s):  
He Wang ◽  
Joan A. Keiser
Keyword(s):  
Cell Death ◽  
Smooth Muscle ◽  
Vascular Smooth Muscle ◽  
Dna Fragmentation ◽  
Cellular Proliferation ◽  
Apoptotic Cell ◽  
Fold Increase ◽  
Enzyme Linked Immunosorbent Assay ◽  
Degenerate Primers ◽  
Conserved Sequence

Vascular remodeling in atherogenesis is marked not only by cellular proliferation and migration but is also impacted by apoptotic cell death. Extensive studies have focused on the signal transduction events leading to apoptosis. CPP32, a member of the caspase/interleukin-1β-converting enzyme (ICE) protease family, has emerged as a central player in several reports of apoptosis pathways. Vascular smooth muscle cells (SMC) undergo apoptosis after treatment with various stimuli, including nitric oxide (NO) donors, such as sodium nitroprusside (SNP, 0.1–1 mM). The aim of the present study was to evaluate the role of CPP32 in SNP-induced apoptosis of SMC. We isolated a rabbit CPP32 cDNA by using degenerate primers and polymerase chain reaction technique. The predicted protein encoded by this cDNA contains the conserved sequence (QACRG) necessary for covalent linkage to poly(ADP-ribose) polymerase (PARP) as well as the three amino acids responsible for substrate recognition and catalysis reported in other caspase members. Using a segment of this cDNA as a probe, we found no change of CPP32 mRNA in cultured arterial SMC before and after SNP treatment. We also measured the protease activity of CPP32 against a chromophore p-nitroaniline (pNA)-labeled substrate, DEVD-pNA. Our results showed a dose-dependent increase of CPP32 activity in SMC, with a maximal 10-fold increase after SNP treatment. Addition of a competitive CPP32 inhibitor, DEVD-CHO, produced a 50% reduction in maximal stimulation. Immunoblot analysis illustrated that SNP treatment induced proteolytic cleavage of CPP32 into its enzymatically active subunit p17 as well as the degradation of PARP into a 85-kDa fragment. We further demonstrated that incubation of cultured SMC with DEVD-CHO significantly reduced SNP-induced DNA fragmentation. DNA fragmentation analysis was carried out using several methods including a cell death detection enzyme-linked immunosorbent assay kit, in situ end labeling, and DNA electrophoresis in agarose gel. Our data indicate that CPP32 mRNA is constitutively expressed in rabbit SMC and activation of CPP32 protein has a pivotal role in SNP-induced SMC apoptosis.

The Flow-Cytometric Analysis of DNA Content and S-Phase Fraction (SPF) of Human Breast Cancer

1989 ◽  
Vol 185 (5) ◽  
pp. 694-697 ◽  
Author(s):  
M. Eskelinen ◽  
S. Nordling ◽  
J. Puittinen ◽  
E. Pesonen ◽  
Y. Collan
Keyword(s):  
Breast Cancer ◽  
Dna Content ◽  
Human Breast Cancer ◽  
Flow Cytometric Analysis ◽  
S Phase ◽  
Phase Fraction ◽  
Human Breast ◽  
Flow Cytometric
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