PMID: 9525810Apr 3, 1998Paper

Drug resistance and apoptosis in ENU-induced rat brain tumors treated with anti-cancer drugs

Journal of Neuro-oncology
T YabunoY Hiasa

Abstract

To cast light on the mechanisms of drug-resistance, experimental brain tumors were immunohistochemically evaluated for expression of glutathione S-transferase (GST)-alpha, mu, pi, p-glycoprotein and apoptosis-related factors, such as bcl-2 and p53, as well as by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL) method. Rat brain tumors induced by means of prenatal exposure to ethylnitrosourea (ENU) were treated with 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) and/or vincristine. Tumors more than 2 mm in size were considered to be drug resistant. The expression of GST-mu was strongly positive in ACNU-treated brain tumors, while p-glycoprotein was overexpressed in vincristine-treated brain tumors. Neither p53 nor bcl-2 expression directly correlated with apoptosis identified by TUNEL method, but tumors lacking apoptotic cells always demonstrated the expression of either GST-mu or p-glycoprotein. These results indicate that tumors resistant to chemotherapy might not be susceptible to induction of apoptosis, and therefore that mechanisms of drug resistance are related to programmed cell death in brain tumors.

Citations

Jul 25, 2015·Archiv der Pharmazie·Mustafa Muhlis Alparslan, Özkan Danış
Dec 18, 2013·The British Journal of Radiology·J M Brown
Oct 31, 2000·Journal of the Neurological Sciences·S WinterM Weller
May 5, 2001·Brain Research. Brain Research Reviews·M Bredel

❮ Previous
Next ❯

Related Concepts

Related Feeds

BCL-2 Family Proteins

BLC-2 family proteins are a group that share the same homologous BH domain. They play many different roles including pro-survival signals, mitochondria-mediated apoptosis and removal or damaged cells. They are often regulated by phosphorylation, affecting their catalytic activity. Here is the latest research on BCL-2 family proteins.

Apoptosis

Apoptosis is a specific process that leads to programmed cell death through the activation of an evolutionary conserved intracellular pathway leading to pathognomic cellular changes distinct from cellular necrosis

© 2022 Meta ULC. All rights reserved