Related Experiment Video

Updated: Aug 18, 2026

Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
07:56

Bacterial Delivery of RNAi Effectors: Transkingdom RNAi

Published on: August 18, 2010

Modulation of BCRP mediated atypical multidrug resistance phenotype by RNA interference

W T Li1, G Y Zhou, X R Song

  • 1Department of Pathology, Medical School, Shandong University, Jinan, 250012 Shandong Province, P.R.China.

Neoplasma
|May 6, 2005
PubMed

Insights

Small interfering RNA (siRNA) targeting breast cancer resistance protein (BCRP) reduced multidrug resistance in cancer cells. While effective, complete reversal was limited by transfection efficiency.

Area of Science:

  • Oncology
  • Molecular Biology
  • Pharmacology

Background:

  • Multidrug resistance (MDR) in human cancers significantly hinders chemotherapy efficacy.
  • Breast cancer resistance protein (BCRP), an ABC transporter, is implicated in atypical MDR.
  • Developing BCRP antagonists is crucial for overcoming treatment failures.

Purpose of the Study:

  • To investigate the potential of small interfering RNA (siRNA) to inhibit BCRP-mediated MDR.
  • To design and evaluate two siRNA constructs targeting different regions of BCRP mRNA.

Main Methods:

  • Two siRNA constructs (pSUPER-BCRP-A and pSUPER-BCRP-B) were designed to target BCRP mRNA.
  • These constructs were transfected into MCF-7/MX100 cell lines to assess their impact on BCRP expression and function.
  • Mitoxantrone resistance index and fluorescence intensity were measured to evaluate MDR reversal.

Main Results:

  • Transfection with pSUPER-BCRP-A and pSUPER-BCRP-B led to decreased mitoxantrone resistance and fluorescence intensity in MCF-7/MX100 cells.
  • Both BCRP mRNA and protein levels were reduced following treatment with the siRNA constructs.
  • The siRNA plasmids demonstrated the ability to reverse BCRP-mediated atypical MDR.

Conclusions:

  • siRNA constructs targeting BCRP can effectively reverse atypical multidrug resistance in cancer cells.
  • Complete reversal of MDR was not achieved, potentially due to limitations in transfection efficiency and transient expression.
  • Further optimization of siRNA delivery and stability is warranted for enhanced therapeutic outcomes.

More Related Videos

Silencing of BRCA2 to Identify Novel BRCA2-regulated Biological Functions in Cultured Human Cells09:24

Silencing of BRCA2 to Identify Novel BRCA2-regulated Biological Functions in Cultured Human Cells

Published on: August 12, 2015

Methods to Discover Alternative Promoter Usage and Transcriptional Regulation of Murine Bcrp111:02

Methods to Discover Alternative Promoter Usage and Transcriptional Regulation of Murine Bcrp1

Published on: May 27, 2016

Related Concept Videos

Experimental RNAi02:15

Experimental RNAi

RNA interference (RNAi) is a cellular mechanism that inhibits gene expression by suppressing its transcription or activating the RNA degradation process. The mechanism was discovered by Andrew Fire and Craig Mello in 1998 in plants. Today, it is observed in almost all eukaryotes, including protozoa, flies, nematodes, insects, parasites, and mammals. This precise cellular mechanism of gene silencing has been developed into a technique that provides an efficient way to identify and determine the...
Types of RNA01:23

Types of RNA

Overview
Three main types of RNA are involved in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA). These RNAs perform diverse functions and can be broadly classified as protein-coding or non-coding RNA. Non-coding RNAs play important roles in the regulation of gene expression in response to developmental and environmental changes. Non-coding RNAs in prokaryotes can be manipulated to develop more effective antibacterial drugs for human or animal use.
RNA...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
RNA Interference01:23

RNA Interference

RNA interference (RNAi) is a process in which a small non-coding RNA molecule blocks the post-transcriptional expression of a gene by binding to its messenger RNA (mRNA) and preventing the protein from being translated.
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
Translational Regulation01:29

Translational Regulation

Translational regulation in prokaryotes ensures efficient protein synthesis by controlling ribosome access to mRNA. This regulation is mediated by secondary RNA structures, including translational riboswitches, RNA thermometers, and small RNAs (sRNAs), which respond to intracellular and environmental signals to modulate gene expression.Translational RiboswitchesRiboswitches in the leader region of mRNAs can regulate translation by altering the accessibility of the Shine-Dalgarno (SD) sequence,...
MicroRNAs01:22

MicroRNAs

MicroRNA (miRNA) are short, regulatory RNA transcribed from introns (non-coding regions of a gene) or intergenic regions (stretches of DNA present between genes). Several processing steps are required to form biologically active, mature miRNA. The initial transcript, called primary miRNA (pri-mRNA), base-pairs with itself, forming a stem-loop structure. Within the nucleus, an endonuclease enzyme, called Drosha, shortens the stem-loop structure into hairpin-shaped pre-miRNA. After the pre-miRNA...