Intracellular levels of cyclic AMP (cAMP), adenylate cyclase, and cAMP-phosphodiesterase activities at lag-period, exponential and stationary growth phases of hepatoma 22a were determined. It was shown that the transition of tumour cells from the lag-period to the exponential phase of growth was accompanied by the two-fold decrease of intracellular cAMP level on account of drastic activation of cAMP phosphodiesterase. Subsequently the cAMP level lowered more slowly until the cells entered the stationary phase of growth. In view of the fact that the adenylate cyclase activity failed to change at different growth phases of hepatoma 22a, it seems very proballe that the rise of cAMP phosphodiesterase activity could be a signal for the exit of tumour cells from the lag-period and their entrance into the mitotic cycle.
Download full-text PDF |
Source |
---|
Int J Mol Sci
August 2024
Faculty of Electronics, Vilnius Gediminas Technical University, 10223 Vilnius, Lithuania.
Electroporation-based procedures employing nanosecond bipolar pulses are commonly linked to an undesirable phenomenon known as the cancelation effect. The cancellation effect arises when the second pulse partially or completely neutralizes the effects of the first pulse, simultaneously diminishing cells' plasma membrane permeabilization and the overall efficiency of the procedure. Introducing a temporal gap between the positive and negative phases of the bipolar pulses during electroporation procedures may help to overcome the cancellation phenomenon; however, the exact thresholds are not yet known.
View Article and Find Full Text PDFAnticancer Agents Med Chem
July 2023
Department of Chemistry, Faculty of Science, Cairo University, Giza, A. R. Egypt.
Background: 2-Amino thiophene derivatives are important compounds not only for their uses in many heterocyclic reactions but also due to their wide range of pharmaceutical and biological activities.
Objective: The aim of this work was to explore a number of new heterocyclic derivatives, studying their inhibitions toward cancer cell lines and studying their structure activity relation ship.
Methods: Alkylation of 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile was achieved through its reaction with chloroacetone and 2-bromo-1-(4-aryl)ethanone derivatives to give compounds 3 and 11a-c.
Bioelectrochemistry
August 2022
Biophysical Research Group, Faculty of Natural Sciences, Vytautas Magnus University, Kaunas, Lithuania. Electronic address:
Targeted and controlled techniques of intratumoral delivery of chemotherapeutic agents are under extensive development, since they diminish detrimental side-effects of conventional anticancer drugs. We investigated the effectiveness of chemotherapy using bleomycin (1 mg/ml) and Sonovue microbubbles combined with: electroporation (EP), mainly designed for subcutaneous tumor therapy, and sonoporation (SP) - for deeper localized tumors. Research was performed on hepatoma MH-22A tumors in murine models, exposed to EP or SP and combined (EP + SP) treatment.
View Article and Find Full Text PDFMembranes (Basel)
February 2022
Department of Biology, Faculty of Natural Sciences, Vytautas Magnus University, 58 K. Donelaičio Str., LT-44248 Kaunas, Lithuania.
High-voltage pulses applied to a cell suspension cause not only cell membrane permeabilization, but a variety of electrolysis reactions to also occur at the electrode-solution interfaces. Here, the cytotoxicity of a culture medium treated by a single electric pulse and the role of the iron ions in this cytotoxicity were studied in vitro. The experiments were carried out on mouse hepatoma MH-22A, rat glioma C6, and Chinese hamster ovary cells.
View Article and Find Full Text PDFMaterials (Basel)
March 2021
Institute of Experimental Medicine, 12 Acad. Pavlov Street, 197376 Saint-Petersburg, Russia.
As shown recently, oleic acid (OA) in complex with lactoferrin (LF) causes the death of cancer cells, but no mechanism(s) of that toxicity have been disclosed. In this study, constitutive parameters of the antitumor effect of LF/OA complex were explored. Complex LF/OA was prepared by titrating recombinant human LF with OA.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!