Related Experiment Video
Updated: Aug 8, 2026

Pooled shRNA Library Screening to Identify Factors that Modulate a Drug Resistance Phenotype
Published on: June 17, 2022
Suppression of P-glycoprotein expression by antipsychotics trifluoperazine in adriamycin-resistant L1210 mouse
Soon Young Shin1, Byeong Hyeok Choi, Jae-Ryong Kim
1Division of Molecular and Life Science, Department of Bio-Nano Technology, College of Science and Technology, Hanyang University, Ansan 426-791, Republic of Korea.
Abstract:
Multidrug resistance (MDR) to unrelated chemotherapeutic drugs can be mediated by overexpression of P-glycoprotein (P-gp), the mdr gene product. Trifluoperazine (TFP), a phenothiazine derivative antipsychotics, is known to reverse MDR of tumor cell lines by blocking P-gp efflux function. In the present study, we evaluated the effect of TFP on the expression of P-gp in multidrug-resistant L1210/Adr mouse leukemic cell lines, which are characterized by overexpession of P-gp. We found that TFP induced the downregulation of P-gp protein and mdr1b mRNA in a dose- and time-dependent manner in L1210/Adr cells. TFP reduction of mdr1b mRNA was paralleled by transcriptional suppression of the mdr1b promoter. Moreover, TFP restored the adriamycin-induced apoptosis in L1210/Adr cells. These results suggest that TFP may have utility as an adjuvant in the therapy of leukemia for the reversal of P-gp-dependent MDR as well as for the management of psychological symptoms in the cancer patients.
Related Concept Videos
Abnormal Proliferation
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase
Antiprotozoal Agents