Paclitaxel (PTX) is one of the most effective drugs used in treatment breast cancer. Nonetheless, appearance MDR1 (multidrug resistance 1) tumor cells has become a significant hindrance for efficacious chemotherapy. In this study, we show that expression level Egr-1 (early growth response gene-1) cancer tissues (from paclitaxel chemotherapy failure patients) and MCF-7/PTX (the cell line was res...

 Background: Chemotherapy plays a very important role in the treatment of leukemia but the resistance properties of the lymphoblasts limit the effect of chemotherapy. One of the main mechanisms of resistance to chemotherapy is the increased expression of MDR1 gene. The aim of this study was to explore the effect of resveratrol on the expression of MDR1 gene in leukemic lymphoblast of new...

Objective: To evaluate the hypothalamic–pituitary–adrenal (HPA) axis in MDR1-1D (dogs with the MDR1 mutation associated with ivermectin sensitivity) and MDR1 wildtype dogs. Design: Prospective study. Setting: Institutional vivarium. Animals: Seven healthy Collie dogs. Measurements: MDR1 genotyping was used for allocation of dogs to 1 of 2 groups: dogs homozygous for the wildtype MDR1 allele (MD...

1-(2-Methoxyethyl)-2-methyl-4,9-dioxo-3-(pyrazin-2-ylmethyl)-4,9-dihydro-1H-naphtho[2,3-d]imidazolium bromide (YM155 monobromide), a novel small molecule that downregulates survivin and exhibits potent antitumor activity, is hydrophilic and cationic. Although previous studies have shown that influx transporters play important roles in the uptake of YM155 into hepatocytes and possibly into cance...

Multidrug resistance (MDR) mediated by P-glycoprotein (MDR1) is clinically significant. Understanding how MDR1 substrate specificity is determined will help to overcome MDR to improve cancer treatment. One potential approach to achieve this goal is to study chimeras of MDR1 and its homolog MDR2 (also called MDR3), which has been identified as a phosphatidylcholine flippase. With an approach inv...

BACKGROUND About one third of patients with epilepsy become refractory to therapy despite receiving adequate medical treatment, possibly from multidrug resistance. P-glycoprotein, encoded by multidrug resistance protein-1 (MDR1) gene, at the blood brain barrier is considered as a major factor mediating drug efflux and contributing to resistance. Given that peripheral blood mononuclear cells (PB...

Levels of mRNA expressed by the multidrug resistance gene MDR1 were examined in 23 renal cell carcinoma samples and adjacent normal kidney cortex using reverse-transcription PCR. Comparison of MDR1 levels between histological types revealed that there was on average significantly more MDR1 in clear cell tumors than in oncocytomas (0. 89 +/- 0.10 versus 0.28 +/- 0.20, ratio of MDR1 in tumor cell...

To overcome the problem of multidrug resistance, we investigated the effectiveness of phosphrothioate antisense oligonucleotides (MDR1-AS) in suppressing multidrug resistance gene (mdr1) expression in drug-resistant acute myelogenous leukemia (AML) blast cells and the K562 adriamycin-resistant cell line K562/ADM. The percentage of cells with the mdr1 gene product P-glycoprotein (P-gp) was decre...