Related Experiment Video

Updated: Jun 13, 2026

Establishing Dual Resistance to EGFR-TKI and MET-TKI in Lung Adenocarcinoma Cells In Vitro with a 2-step Dose-escalation Procedure
09:38

Establishing Dual Resistance to EGFR-TKI and MET-TKI in Lung Adenocarcinoma Cells In Vitro with a 2-step Dose-escalation Procedure

Published on: August 11, 2017

Drug resistant breast cancer cells overexpress ETS1 gene

Meltem Demirel Kars1, Ozlem Darcansoy Işeri, Ufuk Gündüz

  • 1Department of Biological Sciences, Middle East Technical University, Eskisehir Yolu, 06531 Ankara, Turkey.

Biomedicine & Pharmacotherapy = Biomedecine & Pharmacotherapie
|April 16, 2010
PubMed
Abstract

Insights

Multidrug resistance (MDR) in breast cancer cells involves ETS1 overexpression, leading to increased MDR1 gene expression. This study investigated ETS1 and interacting genes in drug-resistant MCF-7 cells, confirming ETS1

Area of Science:

  • Molecular Biology
  • Cancer Research
  • Genetics

Background:

  • Multidrug resistance (MDR) significantly limits chemotherapy efficacy.
  • ETS1 overexpression is implicated in the upregulation of the MDR1 gene, contributing to MDR.
  • Understanding the molecular mechanisms of MDR in breast cancer is crucial for developing effective treatments.

Purpose of the Study:

  • To investigate the role of ETS1 and its interacting genes in drug-resistant MCF-7 breast cancer cells.
  • To assess the expression levels of ETS1 and MDR1 in various drug-resistant sublines.
  • To explore potential mechanisms underlying acquired chemoresistance.

Main Methods:

  • Development of drug-resistant MCF-7 sublines (MCF-7/Pac, MCF-7Doc, MCF-7/Vinc, MCF-7/Dox).
  • cDNA microarray analysis to compare gene expression between sensitive (MCF-7/S) and resistant cells.
  • Immunocytochemistry and western blot to confirm P-gp (MDR1) overexpression.

Main Results:

  • MDR1 and ETS1 genes were significantly overexpressed in all drug-resistant MCF-7 sublines.
  • Matrix metalloproteinase-1 (MMP-1) was upregulated specifically in vincristine-resistant cells.
  • P-glycoprotein (P-gp) was confirmed to be overexpressed in resistant cells, validating MDR1 upregulation.

Conclusions:

  • High ETS1 expression likely drives MDR1 transcription, contributing to multidrug resistance in MCF-7 cells.
  • ETS1 overexpression may be a key factor in the development of chemoresistance.
  • Upregulation of MMP1 and MMP9 in vincristine-resistant cells suggests potential acquired invasive behavior.

Related Concept Videos

Mitogens and the Cell Cycle02:38

Mitogens and the Cell Cycle

Mitogens and their receptors play a crucial role in controlling the progression of the cell cycle. However, the loss of mitogenic control over cell division leads to tumor formation. Therefore, mitogens and mitogen receptors play an important role in cancer research. For instance, the epidermal growth factor (EGF) - a type of mitogen and its transmembrane receptor (EGFR), decides the fate of the cell's proliferation. When EGF binds to EGFR, a member of the ErbB family of tyrosine kinase...
Treatment Resistant Cancers02:56

Treatment Resistant Cancers

Cancer is the second leading cause of death in the United States. A cancer cell is genetically unstable and hence can mutate faster. They can also modify their microenvironment and escape immune surveillance. The difficulties in treating cancer are further compounded by the emergence of rapid resistance to anticancer drugs. The most common ways to attain resistance in cancer cells include alteration in drug transport and metabolism, modification of drug target, elevated DNA damage response, or...
Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase01:11

Pharmacogenetics of Drug Targets: β₂-Adrenergic Receptors, Apo E, Thymidylate Synthase

Genetic polymorphisms in drug targets have emerged as critical determinants of interindividual variability in drug response and toxicity. Pharmacogenomic investigations increasingly focus on identifying these variations to personalize and optimize therapeutic interventions. A drug target may be a receptor, enzyme, or signaling protein involved in pharmacologic responses or disease-related pathways. While early pharmacogenetic studies focused primarily on drug metabolism, current research...
Targeted Cancer Therapies02:57

Targeted Cancer Therapies

The targeted cancer therapies, also known as “molecular targeted therapies,” take advantage of the molecular and genetic differences between the cancer cells and the normal cells. It needs a thorough understanding of the cancer cells to develop drugs that can target specific molecular aspects that drive the growth, progression, and spread of cancer cells without affecting the growth and survival of other normal cells in the body.
There are several types of targeted therapies against specific...
mTOR Signaling and Cancer Progression03:03

mTOR Signaling and Cancer Progression

The mammalian target of rapamycin or mTOR protein was discovered in 1994 due to its direct interaction with rapamycin. The protein gets its name from a yeast homolog called TOR. The mTOR protein complex in mammalian cells plays a major role in balancing anabolic processes such as the synthesis of proteins, lipids, and nucleotides and catabolic processes, such as autophagy in response to environmental cues, such as availability of nutrients and growth factors.
The mTOR pathway or the...