Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2007-8-2
pubmed:abstractText
Histone deacetylase (HDAC) inhibitors such as suberoylanilide hydroxamic acid (SAHA, Vorinostat), valproic acid (VPA), and FK228 are members of a relatively novel class of small molecular weight chemicals that have high antineoplastic activity. They cause growth inhibition and apoptosis specifically in tumor cells, and they act also as chemo- and radio-sensitizers. In the present study, the potential of SAHA and VPA to induce resistance was studied. To that aim HDAC inhibitor-resistant sublines were generated by stepwise exposure of colon tumor cells to increasing concentrations of these compounds. Clonogenic data demonstrated that the SAHA- and VPA-induced sublines were 2-fold resistant to these compounds. This resistance was non-reversible, as it was maintained even when the sublines were cultured in the absence of SAHA or VPA. The SAHA- and VPA-induced resistant sublines were also stably cross-resistant to VPA and SAHA, respectively, but retained sensitivity against non-HDAC inhibitor-type anticancer agents. The SAHA-induced resistance correlated with loss of the G2/M checkpoint but it was not accompanied by reduced induction of the endogenous cell cycle inhibitors p21 and p27. Furthermore, SAHA-induced resistance was not due to reduced apoptosis, and it was neither dependent on MDR expression nor was it due to increased expression of HDAC1 and HDAC3. Taken together, these data demonstrate the potential of SAHA and VPA to induce resistance. This resistance was not dependent on MDR expression, did not involve MMR, and seemed to underlie a mechanism that differs from that underlying the previously observed FK228-induced resistance. The finding that SAHA and VPA induce only modest resistance despite continuous treatment and that the resistance is MDR-independent suggests a preference for these two drugs over FK228 for use in combination treatment with classic anticancer agents.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1019-6439
pubmed:author
pubmed:issnType
Print
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
633-41
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
The histone deacetylase inhibitors suberoylanilide hydroxamic (Vorinostat) and valproic acid induce irreversible and MDR1-independent resistance in human colon cancer cells.
pubmed:affiliation
Department of Gynecology, University Hospital of Zurich, Zurich, Switzerland. andre.fedier@usz.ch
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't