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Updated: Jul 8, 2026

A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells
07:09

A Convenient and General Expression Platform for the Production of Secreted Proteins from Human Cells

Published on: July 31, 2012

P-glycoprotein: so many ways to turn it on

Richard Callaghan1, Emily Crowley, Simon Potter

  • 1Nuffield Department of Clinical Laboratory Sciences, John Radcliffe Hospital, University of Oxford, Oxford, UK. richard.callaghan@ndcls.ox.ac.uk

Journal of Clinical Pharmacology
|December 25, 2007
PubMed

Insights

P-glycoprotein (P-gp or ABCB1) expression drives chemotherapy resistance via cellular stress. However, ABCB1 in normal tissues functions differently, impacting drug pharmacokinetics without stress response involvement.

Area of Science:

  • Biochemistry
  • Pharmacology
  • Cancer Biology

Background:

  • P-glycoprotein (P-gp or ABCB1) is an ABC transporter linked to chemotherapy resistance in cancer.
  • ABCB1 expression is regulated by cellular stress pathways, triggered by chemotherapy or hypoxia.
  • ABCB1 is also present in noncancerous tissues, particularly at barrier and secretory sites.

Purpose of the Study:

  • To review the regulation of ABCB1 expression in both cancerous and noncancerous tissues.
  • To elucidate the distinct mechanisms of ABCB1 expression in normal tissues.
  • To understand the impact of ABCB1 localization on drug pharmacokinetics.

Main Methods:

  • Literature review of studies on ABCB1 expression and regulation.
  • Analysis of ABCB1 localization in normal physiological barriers.
  • Comparison of ABCB1 regulation in cancer versus noncancerous tissues.

Main Results:

  • ABCB1 expression in cancer is often linked to cellular stress responses.
  • ABCB1 is found in barrier tissues (e.g., blood-brain barrier, gut epithelium) and secretory organs.
  • ABCB1 expression in noncancerous tissues does not appear to involve the classical stress response pathway.

Conclusions:

  • ABCB1 plays a critical role in drug pharmacokinetics, affecting absorption and elimination due to its presence in normal tissues.
  • Understanding the distinct regulatory mechanisms of ABCB1 in normal tissues is crucial for drug development and treatment strategies.
  • The differential regulation of ABCB1 highlights its complex role beyond chemotherapy resistance.

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