Loading…
Expanding the Roles for Pregnane X Receptor in Cancer: Proliferation and Drug Resistance in Ovarian Cancer
Purpose: We examined the presence of the pregnane X receptor (PXR) and its effects on ovarian cancer cells after activation by its cognate ligand. Experimental Design: SKOV-3 and OVCAR-8 ovarian carcinoma cells were analyzed for expression of PXR by quantitative reverse transcription-PCR and Western...
Saved in:
Published in: | Clinical cancer research 2008-09, Vol.14 (17), p.5332-5340 |
---|---|
Main Authors: | , , , , , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | Purpose: We examined the presence of the pregnane X receptor (PXR) and its effects on ovarian cancer cells after activation by its
cognate ligand.
Experimental Design: SKOV-3 and OVCAR-8 ovarian carcinoma cells were analyzed for expression of PXR by quantitative reverse transcription-PCR
and Western blot. Human ovarian cancer tissue was also analyzed for PXR expression by immunochemistry. Ligand (agonist)–induced
PXR target genes were analyzed in SKOV-3 cells by quantitative reverse transcription-PCR. SKOV-3 cell proliferation was assessed
by MTT assay. In vivo confirmation of in vitro effects of PXR ligands were done in NOD.SCID mice carrying SKOV-3 xenografts.
Results: PXR is expressed in ovarian cancer cells. In SKOV-3 cells, PXR is functional and its activation by cognate ligands induces
PXR target genes (CYP2B6, CYP3A4, and UGT1A1) but not MDR1 and MRP2. PXR activation in SKOV-3 cells induces cell proliferation
and drug resistance. In mice harboring SKOV-3 xenografts, rifampicin (PXR agonist) induces cell proliferation and tumor growth.
Conclusion: PXR activation, regardless of the type of ligand agonist present, promotes the “malignant” phenotype of cancer cells. These
data serve as the basis for finding novel nontoxic inhibitors of PXR activation as a method to control cell growth and prevent
induction of drug resistance. |
---|---|
ISSN: | 1078-0432 1557-3265 |
DOI: | 10.1158/1078-0432.CCR-08-1033 |