SV40-3T3 cells were exposed in monolayer cultures to 5 X 10(-7) M methotrexate (MTX), that inhibited thymidylate synthetase, arrested cell growth without cell killing in 24 h and did not induce single- (ss) or double-strand (ds) breaks in DNA. Following 24, up to 72 h, the poly(ADP-ribose) polymerase content of attached cells was induced by 5 X 10(-7) M MTX and the augmentation of the enzyme increased with the time of exposure to the drug. Inhibition of protein or RNA synthesis abolished augmentation of enzymatic activity; so too did the initiation of maximal cell growth by thymidine + hypoxanthine, by-passing the inhibitory site of MTX. Isolation of the ADP-ribosylated enzyme protein by gel electrophoresis identified poly(ADP-ribose) polymerase protein as the molecule that was induced by 5 X 10(-7) M MTX. Under identical conditions, the poly(ADP-ribose) polymerase induction in 3T3 cells could not be demonstrated. A possible cell-cycle-dependent biosynthesis of the enzyme protein is proposed in SV40 3T3 cells.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/0014-4827(87)90119-4 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Acute copper stress showed toxic effects on the physiological metabolism of Ulva lactuca, a common green macroalgae.
Sci Rep
October 2024
Institute of Tropical Eco-Agriculture, Yunnan Academy of Agricultural Sciences, Kunming, 651300, Yunnan Province, China.
The pollution by heavy metals in coastal waters has gradually intensified due to industrial development. In this study, physiological responses of Ulva lactuca, one of the most common green seaweeds with important ecological and economic value in the global intertidal zone, to acute copper stress were investigated. Results showed that an increase in copper ions concentration significantly inhibited photosynthetic activity and inorganic nitrogen utilization by U.
View Article and Find Full Text PDFReal-world trends in the use of maintenance therapy in ovarian cancer across the United States from 2017 to 2021.
Gynecol Oncol
November 2024
Department of Gynecologic Oncology and Reproductive Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. Electronic address:
Objective: We assessed real-world trends in the use of maintenance therapy [MT] (i.e., polyADP-ribose polymerase inhibitors (PARPi) and/or bevacizumab following platinum-based chemotherapy), among U.
View Article and Find Full Text PDFActivation of retinoid X receptors protects retinal neurons and pigment epithelial cells from BMAA-induced death.
Biochim Biophys Acta Mol Cell Res
December 2024
Instituto de Investigaciones Bioquímicas de Bahía Blanca, Departamento de Biología, Bioquímica y Farmacia, Universidad Nacional del Sur - Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Bahía Blanca, Argentina. Electronic address:
Exposure to the non-protein amino acid cyanotoxin β-N-methylamino-L-alanine (BMAA), released by cyanobacteria found in many water reservoirs has been associated with neurodegenerative diseases. We previously demonstrated that BMAA induced cell death in both retina photoreceptors (PHRs) and amacrine neurons by triggering different molecular pathways, as activation of NMDA receptors and formation of carbamate-adducts was only observed in amacrine cell death. We established that activation of Retinoid X Receptors (RXR) protects retinal cells, including retina pigment epithelial (RPE) cells from oxidative stress-induced apoptosis.
View Article and Find Full Text PDFMolecular consequences of acute versus chronic CDK12 loss in prostate carcinoma nominates distinct therapeutic strategies.
bioRxiv
July 2024
Division of Human Biology, Fred Hutchinson Cancer Center, Seattle, WA 98119.
Genomic loss of the transcriptional kinase occurs in ~6% of metastatic castration-resistant prostate cancers (mCRPC) and correlates with poor patient outcomes. Prior studies demonstrate that acute CDK12 loss confers a homologous recombination (HR) deficiency (HRd) phenotype via premature intronic polyadenylation (IPA) of key HR pathway genes, including However, mCRPC patients have not demonstrated benefit from therapies that exploit HRd such as inhibitors of polyADP ribose polymerase (PARP). Based on this discordance, we sought to test the hypothesis that an HRd phenotype is primarily a consequence of acute loss and the effect is greatly diminished in prostate cancers adapted to loss.
View Article and Find Full Text PDFNew hopes and promises in the treatment of ovarian cancer focusing on targeted treatment-a narrative review.
Front Pharmacol
June 2024
1st Chair and Department of Oncological Gynaecology and Gynaecology, Medical University of Lublin, Lublin, Poland.
Unfortunately, ovarian cancer is still diagnosed most often only in an advanced stage and is also the most lethal gynecological cancer. Another problem is the fact that treated patients have a high risk of disease recurrence. Moreover, ovarian cancer is very diverse in terms of molecular, histological features and mutations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!