Genomic and molecular profiling predicts response to temozolomide in melanoma

Christina K. Augustine, Jin Soo Yoo, Anil Potti, Yasunori Yoshimoto, Patricia A. Zipfel, Henry S. Friedman, Joseph R. Nevins, Francis Ali-Osman, Douglas Tyler

Research output: Contribution to journalArticle

77 Scopus citations

Abstract

Purpose: Despite objective response rates of only ∼13%, temozolomide remains one of the most effective single chemotherapy agents against metastatic melanoma, second only to dacarbazine, the current standard of care for systemic treatment of melanoma. The goal of this study was to identify molecular and/or genetic markers that correlate with, and could be used to predict, response to temozolomide-based treatment regimens and that reflect the intrinsic properties of a patient's tumor. Experimental Design: Using a panel of 26 human melanoma-derived cell lines, we determined in vitro temozolomide sensitivity, O 6-methylguanine-DNA methyltransferase (MGMT) activity, MGMT expression and promoter methylation status, and mismatch repair proficiency, as well as the expression profile of 38,000 genes using an oligonucleotide-based microarray platform. Results: The results showed a broad spectrum of temozolomide sensitivity across the panel of cell lines, with IC 50 values ranging from 100 μmol/L to 1 mmol/L. There was a significant correlation between measured temozolomide sensitivity and a gene expression signature-derived prediction of temozolomide sensitivity (P < 0.005). Notably, MGMT alone showed a significant correlation with temozolomide sensitivity (MGMT activity, P < 0.0001; MGMT expression, P ≤ 0.0001). The promoter methylation status of the MGMT gene, however, was not consistent with MGMT gene expression or temozolomide sensitivity. Conclusions: These results show that melanoma resistance to temozolomide is conferred predominantly by MGMT activity and suggest that MGMT expression could potentially be a useful tool for predicting the response of melanoma patients to temozolomide therapy.

Original languageEnglish (US)
Pages (from-to)502-510
Number of pages9
JournalClinical Cancer Research
Volume15
Issue number2
DOIs
StatePublished - Jan 15 2009
Externally publishedYes

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ASJC Scopus subject areas

  • Cancer Research
  • Oncology

Cite this

Augustine, C. K., Yoo, J. S., Potti, A., Yoshimoto, Y., Zipfel, P. A., Friedman, H. S., Nevins, J. R., Ali-Osman, F., & Tyler, D. (2009). Genomic and molecular profiling predicts response to temozolomide in melanoma. Clinical Cancer Research, 15(2), 502-510. https://doi.org/10.1158/1078-0432.CCR-08-1916