Cited by 151Glioma Diagnosis and TreatmentEpigenetics and DNA MethylationPARP inhibition in cancer therapy

Inhibition of histone deacetylation potentiates the evolution of acquired temozolomide resistance linked to MGMT upregulation in glioblastoma xenografts

Open access
Kitange, Gaspar J., Mladek, Ann C., Carlson, Brett L., Schroeder, Mark A., Pokorny, Jenny L., Cen, Ling, Decker, Paul A., Wu, Wenting +4 more·2012·Clinical Cancer Research

Published version of a preprint

Abstract

Purpose: The therapeutic benefit of temozolomide in glioblastoma multiforme (GBM) is limited by resistance. The goal of this study was to elucidate mechanisms of temozolomide resistance in GBM. Experimental Design: We developed an in vivo GBM model of temozolomide resistance and used paired parental and temozolomide-resistant tumors to define the mechanisms underlying the development of resistance and the influence of histone deacetylation (HDAC) inhibition. Results: Analysis of paired parental and resistant lines showed upregulation of O6-methylguanine-DNA methyltransferase (MGMT) expression in 3 of the 5 resistant xenografts. While no significant change was detected in MGMT promoter methylation between parental and derivative-resistant samples, chromatin immunoprecipitation showed an association between MGMT upregulation and elevated acetylation of lysine 9 of histone H3 (H3K9-ac) and decreased dimethylation (H3K9-me2) in GBM12 and GBM14. In contrast, temozolomide resistance development in GBM22 was not linked to MGMT expression, and both parental and resistant lines had low H3K9-ac and high H3K9-me2 within the MGMT promoter. In the GBM12TMZ-resistant line, MGMT reexpression was accompanied by increased recruitment of SP1, C-JUN, NF-κB, and p300 within the MGMT promoter. Interestingly, combined treatment of GBM12 flank xenografts with temozolomide and the HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) favored the evolution of temozolomide resistance by MGMT overexpression as compared with treatment with temozolomide alone. Conclusion: This study shows, for the first time, a unique mechanism of temozolomide resistance development driven by chromatin-mediated MGMT upregulation and highlights the potential for epigenetically directed therapies to influence the mechanisms of resistance development in GBM. Clin Cancer Res; 18(15); 4070–9. ©2012 AACR.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1158/1078-0432.ccr-12-0560

Cites

32 of 32 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • HDAC inhibitor SAHA shows strong effects in destabilizing mut-p53 by dissociating HDAC6 from functional interaction with Hsp90 and thereby inhibits glioblastoma growth and resistance to chemotherapy.

    “HDAC inhibitor SAHA shows strong effects in destabilizing mut-p53 by dissociating HDAC6 from functional interaction with Hsp90 and thereby inhibits GBM growth and resistance to chemotherapy [142,143,144,145,146].”

    From The p53 Pathway in Glioblastoma (2018) · cites this paper as [143]

    The Results (Influence of HDAC inhibition on MGMT upregulation; page not provided) found no significant tumor-growth benefit from SAHA alone and no significant efficacy difference between temozolomide alone and temozolomide plus SAHA. SAHA co-treatment instead promoted MGMT upregulation, a mechanism of temozolomide resistance. The cited passages do not describe mutant-p53 destabilization or an HDAC6–Hsp90 interaction. (LLM, conf=0.88)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

1 of the 33 references couldn’t be matched to a known paper.

Cited by

Sorted by citations

Authors
Kitange, G. J., Mladek, A. C., Carlson, B. L., Schroeder, M. A., Pokorny, J. L., Cen, L., Decker, P. A., Wu, W., Lomberk, G. A., Gupta, S. K., Urrutia, R. A., & Sarkaria, J. N.
Affiliations
Mayo Clinic (US)
Corresponding author
Kitange, Gaspar J.
Venue
Clinical Cancer Research
Published
2012-07-30
Volume
18
Issue
15
Pages
4070-4079
ISSN
  • 1078-0432 (ISSN-L)
  • 1557-3265
OpenAlex
W2135891497
Cited by
151
References
33
Citations by year
2026: 6 · 2025: 5 · 2024: 14 · 2023: 14 · 2022: 9 · 2021: 14 · 2020: 9 · 2019: 13 · 2018: 14 · 2017: 8 · 2016: 10 · 2015: 14 · 2014: 12 · 2013: 7 · 2012: 2
FWCI
5.34
Type
journal article
Language
en
Open access
Locations
  • Clinical Cancer Research (publishedVersion)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • Mayo Clinic
  • National Cancer Institute (R01CA127716, R01CA141121, P50CA108961)
  • National Institute of Diabetes and Digestive and Kidney Diseases (R01DK052913)
Topics
  • Health Sciences › Medicine › Genetics › Glioma Diagnosis and Treatment
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Epigenetics and DNA Methylation
  • Health Sciences › Medicine › Oncology › PARP inhibition in cancer therapy
Keywords
temozolomide resistance, glioblastoma, histone deacetylase inhibition, O6-methylguanine-DNA methyltransferase, histone H3 lysine 9 acetylation, H3K9me2, MGMT promoter, chromatin remodeling, Sp1, NF-κB, P300, vorinostat, epigenetic therapy, xenograft models
MeSH terms
Temozolomide, Vorinostat, Acetylation, Animals, Dacarbazine, Glioblastoma, Histones, Humans, Hydroxamic Acids, Methylation, Promoter Regions, Genetic, Blotting, Western, DNA Modification Methylases, Up-Regulation, Gene Expression Regulation, Neoplastic, Antineoplastic Agents, Alkylating, Drug Resistance, Neoplasm, DNA Methylation, Reverse Transcriptase Polymerase Chain Reaction, Xenograft Model Antitumor Assays, Tumor Suppressor Proteins, DNA Repair Enzymes, Mice, Kaplan-Meier Estimate, Histone Deacetylase Inhibitors

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review