ABCB1 (P-glycoprotein) is an efflux transporter that limits the cellular uptake levels of various drugs in intestine, brain, and other tissues. The expression of human ABCB1 has recently been reported to be under the control of nuclear receptor NR1I subfamily members, pregnane X receptor (PXR, NR1I2) and constitutive androstane receptor (CAR, NR1I3). Here, we have investigated the involvement o...

Multidrug resistance (MDR) attenuates the chemotherapy efficacy and increases the probability of cancer recurrence. The accelerated drug efflux mediated by ATP-binding cassette (ABC) transporters is one of the major MDR mechanisms. This study investigated if TTT-28, a newly synthesized thiazole-valine peptidomimetic, could reverse ABCB1-mediated MDR in vitro and in vivo. TTT-28 reversed the ABC...

ABCB1, also known as P-glycoprotein (P-gp) or multidrug resistance protein 1 (MDR1), is a membrane-associated multidrug transporter of the ATP-binding cassette (ABC) transporter family. It is one of the most widely studied transporters that enable cancer cells to develop drug resistance. Reliable high-throughput assays that can identify compounds that interact with ABCB1 are crucial for develop...

Background: Imatinib mesylate (IM), a strong and selective tyrosine kinase inhibitor, has been approved as the front line of treatment in chronic myeloid leukemia (CML) patients. In spite of satisfactory results of imatinib in the treatment of patients with CML, patients with treatment failure or suboptimal response developed resistance that might be because of pharmacogenetic variants. This st...

The clinical efficacy of a systemically administered drug acting on the central nervous system depends on its ability to pass the blood-brain barrier, which is regulated by transporter molecules such as ABCB1 (MDR1). Here we report that polymorphisms in the ABCB1 gene predict the response to antidepressant treatment in those depressed patients receiving drugs that have been identified as substr...

One of the major causes of chemotherapy failure in cancer treatment is multidrug resistance (MDR) which is mediated by the ABCB1/P-glycoprotein. Previously, through the use of an extensive screening process, we found that vardenafil, a phosphodiesterase 5 (PDE-5) inhibitor significantly reverses MDR in ABCB1 overexpressing cancer cells, and its efficacy was greater than that of tadalafil, anoth...

Overexpression of ABCB1 (also called P-glycoprotein) confers resistance to multiple anticancer drugs, including tyrosine kinase inhibitors (TKIs). Several ABCB1 single nucleotide polymorphisms affect the transporter activity. The most common ABCB1 variants are 1236C > T, 2677G > T, 3435C > T and have been associated with clinical response to imatinib in chronic myelogenous leukaemia (CML) in so...