scholarly journals Evolutionary conservation in various mammalian species of the human proliferation-associated epitope recognized by the Ki-67 monoclonal antibody.

1989 ◽  
Vol 37 (10) ◽  
pp. 1471-1478 ◽  
Author(s):  
B Falini ◽  
L Flenghi ◽  
M Fagioli ◽  
H Stein ◽  
R Schwarting ◽  
...  

The human proliferation-associated epitope recognized by the Ki-67 monoclonal antibody (MAb) was detected in proliferating normal and neoplastic cells of many mammalian species (lamb, calf, dog, rabbit, rat) besides human. In contrast, Ki-67 stained proliferating cells from other species weakly (mouse) or not at all (swine, cat, chicken, pigeon). The immunostaining pattern of Ki-67 in animal tissues was identical to that previously described in human: Ki-67 reacted only with cells known to proliferate (e.g., germinal center cells, cortical thymocytes) but not with resting cells (e.g., hepatocytes, brain cells, renal cells); this MAb produced a characteristic nuclear staining pattern (e.g., stronger labeling of nucleoli than of the rest of the nuclei and staining of chromosomes in mitotic figures); and Ki-67 crossreacted with the squamous epithelium in both animal and human tissues. In vitro studies showed that when quiescent (Ki-67-negative) NIH 3T3 fibroblasts or bovine peripheral blood lymphocytes were induced to proliferate, the appearance of Ki-67-positive cells paralleled the induction of cell proliferation caused by addition of fetal calf serum or PHA, respectively, to the cultures, and in both human and rat proliferating cells the Ki-67 expression closely paralleled the incorporation of [3H]-thymidine. These findings indicate that the epitope recognized by the Ki-67 MAb in human and animal species is the same. The widespread evolutionary conservation of the human proliferation-associated epitope recognized by the Ki-67 MAb suggests that it and/or its carrier molecule may play an important role in regulation of cell proliferation.

1983 ◽  
Vol 38 (1-2) ◽  
pp. 74-78 ◽  
Author(s):  
R. Maschler ◽  
C. J. Smith ◽  
J. C. Allen ◽  
H. R. Maurer

Using T-lymphocyte and granulocyte colony assays with truly proliferating cells the effects of the polyamine spermine and of other naturally-occurring inhibitors of cell proliferation have been differentiated. It has been confirmed that spermine, in the presence of fetal calf serum, is a potent inhibitor of cell proliferation. This inhibition could be reversed by the addition of either 3- hydroxybenzyl-oxyamine or 4-bromo-3-hydroxybenzyl-oxyamine, both of which are inhibitors of the polyamine oxidase. In comparison, fractions isolated from calf thymus were shown to inhibit lymphocyte, but not granulocyte colony growth, indicating their tissue specificity and lymphocyte chalone activity. Further this inhibition was not reversed by polyamine oxidase inhibitors demonstrating that polyamines were not the inhibitory principles in this preparation.


2021 ◽  
Vol 22 (9) ◽  
pp. 4390
Author(s):  
Jana Horváthová ◽  
Roman Moravčík ◽  
Miroslava Matúšková ◽  
Vladimír Šišovský ◽  
Andrej Boháč ◽  
...  

A high rate of glycolysis is considered a hallmark of tumor progression and is caused by overexpression of the enzyme 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3). Therefore, we analyzed the possibility of inhibiting tumor and endothelial cell metabolism through the inhibition of PFKFB3 by a small molecule, (E)-1-(pyridin-4-yl)-3-(quinolin-2-yl)prop-2-en-1-one (PFK15), as a promising therapy. The effects of PFK15 on cell proliferation and apoptosis were analyzed on human umbilical vein endothelial cells (HUVEC) and the human colorectal adenocarcinoma cell line DLD1 through cytotoxicity and proliferation assays, flow cytometry, and western blotting. The results showed that PFK15 inhibited the proliferation of both cell types and induced apoptosis with decreasing the Bcl-2/Bax ratio. On the basis of the results obtained from in vitro experiments, we performed a study on immunodeficient mice implanted with DLD1 cells. We found a reduced tumor mass after morning PFK15 treatment but not after evening treatment, suggesting circadian control of underlying processes. The reduction in tumor size was related to decreased expression of Ki-67, a marker of cell proliferation. We conclude that inhibition of glycolysis can represent a promising therapeutic strategy for cancer treatment and its efficiency is circadian dependent.


2000 ◽  
Vol 113 (17) ◽  
pp. 3117-3123 ◽  
Author(s):  
C. Wadham ◽  
J.R. Gamble ◽  
M.A. Vadas ◽  
Y. Khew-Goodall

Pez is a non-transmembrane tyrosine phosphatase with homology to the FERM (4.1, ezrin, radixin, moesin) family of proteins. The subcellular localisation of Pez in endothelial cells was found to be regulated by cell density and serum concentration. In confluent monolayers Pez was cytoplasmic, but in cells cultured at low density Pez was nuclear, suggesting that it is a nuclear protein in proliferating cells. This notion is supported by the loss of nuclear Pez when cells are serum-starved to induce quiescence, and the rapid return of Pez to the nucleus upon refeeding with serum to induce proliferation. Vascular endothelial cells normally exist as a quiescent confluent monolayer but become proliferative during angiogenesis or upon vascular injury. Using a ‘wound’ assay to mimic these events in vitro, Pez was found to be nuclear in the cells that had migrated and were proliferative at the ‘wound’ edge. TGFbeta, which inhibits cell proliferation but not migration, inhibited the translocation of Pez to the nucleus in the cells at the ‘wound’ edge, further strengthening the argument that Pez plays a role in the nucleus during cell proliferation. Together, the data presented indicate that Pez is a nuclear tyrosine phosphatase that may play a role in cell proliferation.


Cancers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 227 ◽  
Author(s):  
Miguel Mateu-Sanz ◽  
Juan Tornín ◽  
Bénédicte Brulin ◽  
Anna Khlyustova ◽  
Maria-Pau Ginebra ◽  
...  

Osteosarcoma (OS) is the main primary bone cancer, presenting poor prognosis and difficult treatment. An innovative therapy may be found in cold plasmas, which show anti-cancer effects related to the generation of reactive oxygen and nitrogen species in liquids. In vitro models are based on the effects of plasma-treated culture media on cell cultures. However, effects of plasma-activated saline solutions with clinical application have not yet been explored in OS. The aim of this study is to obtain mechanistic insights on the action of plasma-activated Ringer’s saline (PAR) for OS therapy in cell and organotypic cultures. To that aim, cold atmospheric plasma jets were used to obtain PAR, which produced cytotoxic effects in human OS cells (SaOS-2, MG-63, and U2-OS), related to the increasing concentration of reactive oxygen and nitrogen species generated. Proof of selectivity was found in the sustained viability of hBM-MSCs with the same treatments. Organotypic cultures of murine OS confirmed the time-dependent cytotoxicity observed in 2D. Histological analysis showed a decrease in proliferating cells (lower Ki-67 expression). It is shown that the selectivity of PAR is highly dependent on the concentrations of reactive species, being the differential intracellular reactive oxygen species increase and DNA damage between OS cells and hBM-MSCs key mediators for cell apoptosis.


Blood ◽  
1995 ◽  
Vol 85 (7) ◽  
pp. 1871-1880 ◽  
Author(s):  
L Flenghi ◽  
M Fagioli ◽  
L Tomassoni ◽  
S Pileri ◽  
M Gambacorta ◽  
...  

PG-M3 is a new monoclonal antibody (MoAb) specifically directed against a peptide sequence located in the aminoterminal region of the human PML protein. PML gene fuses with the retinoic acid receptor alpha (RAR alpha) gene during the t(15; 17) chromosomal translocation of acute promyelocytic leukemia (APL). The epitope recognized by PG-M3 is species-specific and fixative-resistant and is shared by most PML isoforms and PML/RAR alpha fusion proteins. PML is consistently located within the nucleus, although a minority of cells (about 20%), both in vitro and in vivo, show positivity for PML also in the cytoplasm. The nuclear staining pattern of PG-M3 varies from speckled (cells other than APL) to micropunctate (APL cells). Although two physiologically expressed PML isoforms are detectable by immunocytochemistry only or predominantly in the cytoplasm of transfected cells, the cytoplasmic localization of PML is a property also shared by the PML isoforms that predominantly localize to the nuclei. Immunohistologic analysis of normal human tissues with the PG-M3 MoAb showed variable PML expression, with the highest levels of the protein in postmitotic, differentiated cell types, such as endothelial cells, epithelia, and tissue macrophages, especially activated ones. In keeping with this in vivo finding, PML appears strongly upregulated in the U937 promonocyte cell line after exposure to agents that induce monocyte/macrophage activation (interferon gamma) or maturation (vitamin D3 and transforming growth factor beta 1).


2019 ◽  
Vol 9 (7) ◽  
pp. 982-987
Author(s):  
Xiaoying Wang ◽  
Yanke Hao

Vascular smooth muscle cell (VSMC) abnormal proliferation is related to hypertension. P27 can arrest cell cycle and its downregulation is associated with hypertension. miR-155 plays a regulatory role in VSMC proliferation, while its relationship with hypertension is still unclear. Bioinformatics analysis reveals a relationship between p27 mRNA and miR-155. The present study explores miR-155's role in p27 expression, VSMC proliferation and apoptosis, as well as in the pathogenesis of hypertension. Dual luciferase assay verified the relationship between miR-155 and p27. miR155, p27, α-SMA, and Ki-67 expressions in the thoracic aorta media of rat hypertension model were detected. VSMCs were cultured in vitro and grouped into, anti-miR-NC, anti-miR-155, pIRES2-blank, pIRES2-p27, and anti-miR-155 + pIRES2-p27 groups followed by analysis of cell cycle by flow cytometry and cell proliferation by EdU staining. Hypertension rats were randomly divided into antagomir-155 and antagomir-control. Caudal artery systolic and diastolic pressures were measured. miR-155 suppressed p27 expression. miR-155 and Ki-67 expressions were significantly enhanced, while p27 and α-SMA levels were reduced in the tunica media from hypertension rats compared with control. Downregulation of miR-155 and/or upregulation of p27 obviously declined cell proliferation and arrested cell cycle in G1 phase. Antagomir-155 injection significantly decreased systolic and diastolic pressures, elevated p27 and α-SMA expressions in media, and reduced the thickness of tunica media. miR-155 enhances VSMC proliferation via regulating p27. miR-155 enhancement was related to hypertension. miR-155 plays a therapeutic effect in hypertension.


2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13170-13170
Author(s):  
M. P. Morelli ◽  
T. Cascone ◽  
T. Troiani ◽  
C. Tuccillo ◽  
R. Bianco ◽  
...  

13170 Background: The epidermal growth factor receptor (EGFR) autocrine pathway plays an important role in cancer cell growth. Vascular endothelial growth factor A (VEGF-A) is a key regulator of tumor-induced endothelial cell proliferation and vascular permeability. ZD6474 (ZACTIMA™) is an orally available, small molecule inhibitor of VEGF receptor-2 (VEGFR-2), EGFR and RET tyrosine kinase activity. We investigated the activity of ZD6474 in combination with cetuximab, an anti-EGFR blocking monoclonal antibody, to determine the antitumor activity of EGFR blockade through the combined use of two agents targeting the receptor at different molecular sites in cancer cells and of VEGFR-2 blockade in endothelial cells. Methods: The antitumor activity in vitro and in vivo of ZD6474 and/or cetuximab was tested in human cancer cell lines with a functional EGFR autocrine pathway. Results: In vitro, the combination of ZD6474 and cetuximab produced synergistic growth inhibition in all cancer cell lines tested as assessed by the Chou and Talalay method. In vivo, 4 weeks of treatment with ZD6474 (75 mg/kg p.o., days 1–5 each week) or cetuximab (1 mg i.p., days 2 and 5 each week) produced a tumor growth delay of 21–28 days (P < 0.001) in nude mice bearing established human colon carcinoma (GEO) or lung adenocarcinoma (A549) cancer xenografts compared with untreated controls. Combination treatment with ZD6474 and cetuximab for 4 weeks resulted in a more marked tumor growth delay of 120–140 days compared with controls, and this was significantly greater than with either single agent therapy (P < 0.001). Following combination treatment, 3/10 A549 xenograft-bearing mice and 4/10 GEO xenograft-bearing mice had no histologic evidence of tumor at the end of the experiment. Immunohistochemical analysis of tumor samples obtained from mice treated with the two drugs in combination demonstrated a cooperative inhibition of cancer cell proliferation and an almost complete suppression of tumor angiogenesis. Conclusions: This study provides a rationale for evaluating in a clinical setting the double blockade of EGFR in combination with inhibition of VEGFR-2 signaling as cancer therapy. [Table: see text]


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