CDO1 promoter methylation is a biomarker for outcome prediction of anthracycline treated, estrogen receptor-positive, lymph node-positive breast cancer patients.
BACKGROUND
Various biomarkers for prediction of distant metastasis in lymph-node negative breast cancer have been described; however, predictive biomarkers for patients with lymph-node positive (LNP) disease in the context of distinct systemic therapies are still very much needed. DNA methylation is aberrant in breast cancer and is likely to play a major role in disease progression. In this study, the DNA methylation status of 202 candidate loci was screened to identify those loci that may predict outcome in LNP/estrogen receptor-positive (ER+) breast cancer patients with adjuvant anthracycline-based chemotherapy.


METHODS
Quantitative bisulfite sequencing was used to analyze DNA methylation biomarker candidates in a retrospective cohort of 162 LNP/ER+ breast cancer patients, who received adjuvant anthracycline-based chemotherapy. First, twelve breast cancer specimens were analyzed for all 202 candidate loci to exclude genes that showed no differential methylation. To identify genes that predict distant metastasis, the remaining loci were analyzed in 84 selected cases, including the 12 initial ones. Significant loci were analyzed in the remaining 78 independent cases. Metastasis-free survival analysis was conducted by using Cox regression, time-dependent ROC analysis, and the Kaplan-Meier method. Pairwise multivariate regression analysis was performed by linear Cox Proportional Hazard models, testing the association between methylation scores and clinical parameters with respect to metastasis-free survival.


RESULTS
Of the 202 loci analysed, 37 showed some indication of differential DNA methylation among the initial 12 patient samples tested. Of those, 6 loci were associated with outcome in the initial cohort (n = 84, log rank test, p < 0.05).Promoter DNA methylation of cysteine dioxygenase 1 (CDO1) was confirmed in univariate and in pairwise multivariate analysis adjusting for age at surgery, pathological T stage, progesterone receptor status, grade, and endocrine therapy as a strong and independent biomarker for outcome prediction in the independent validation set (log rank test p-value = 0.0010).


CONCLUSIONS
CDO1 methylation was shown to be a strong predictor for distant metastasis in retrospective cohorts of LNP/ER+ breast cancer patients, who had received adjuvant anthracycline-based chemotherapy.
Epigenomics AG, Berlin, Germany. dimo.dietrich@epigenomics.com
Dimo
D
Dietrich
Manuel
M
Krispin
Jörn
J
Dietrich
Anne
A
Fassbender
Jörn
J
Lewin
Nadia
N
Harbeck
Manfred
M
Schmitt
Serenella
S
Eppenberger-Castori
Vincent
V
Vuaroqueaux
Frédérique
F
Spyratos
John A
JA
Foekens
Ralf
R
Lesche
John W M
JW
Martens
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018943:Anthracyclines / Q000008:administration & dosage; D000903:Antibiotics, Antineoplastic / Q000008:administration & dosage; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics* / Q000401:mortality / Q000556:secondary; D017024:Chemotherapy, Adjuvant; D050558:Cysteine Dioxygenase / Q000235:genetics*; D019175:DNA Methylation; D005060:Europe; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011401:Promoter Regions, Genetic; D016016:Proportional Hazards Models; D012372:ROC Curve; D011960:Receptors, Estrogen / Q000032:analysis*; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
D018943:Anthracyclines; D000903:Antibiotics, Antineoplastic; D014408:Biomarkers, Tumor; D011960:Receptors, Estrogen; D050558:Cysteine Dioxygenase