Expression profiling identifies genes that predict recurrence of breast cancer after adjuvant CMF-based chemotherapy
- 246 Downloads
Cyclophosphamide, methotrexate and 5-fluorouracile (CMF)-based chemotherapy for adjuvant treatment of breast cancer reduces the risk of relapse. In this exploratory study, we tested the feasibility of identifying molecular markers of recurrence in CMF-treated patients. Using Affymetrix U133A GeneChips, RNA samples from 19 patients with primary breast cancer who had been uniformly treated with adjuvant CMF chemotherapy were analyzed. Two supervised class prediction approaches were used to identify gene markers that can best discriminate between patients who would experience relapse and patients who would remain disease-free. An additional independent validation set of 51 patients and 21 genes were analyzed by quantitative RT-PCR. Applying different algorithms to evaluate our microarray data, we identified two gene expression signatures of 21 and 12 genes containing eight overlapping genes, that predict recurrence in 19 cases with high accuracy (94%). Quantitative RT-PCR demonstrated that six genes from the combined signatures (CXCL9, ITSN2, GNAI2, H2AFX, INDO, and MGC10986) were significantly differentially expressed in the recurrence versus the non-recurrence group of the 19 cases and the independent breast cancer patient cohort (n = 51) treated with CMF. High expression levels of CXCL9, ITSN2, and GNAI2 were associated with prolonged disease-free survival (DFS) (P = 0.029, 0.018 and 0.032, respectively). When patients were stratified by combined CXCL9/ITSN2 or CXCL9/FLJ22028 tumor levels, they exhibited significantly different disease-free survival curves (P = 0.0073 and P = 0.005, respectively). Finally, the CXCL9/ITSN2 and CXCL9/FLJ22028 ratio was an independent prognostic factor (P = 0.034 and P = 0.003, respectively) for DFS by multivariate Cox analysis in the 70-patient cohort. Our data highlight the feasibility of a prognostic assay that is applicable to therapeutic decision-making for breast cancer. Whether the biomarker profile is chemotherapy-specific or whether it is a more general indicator of bad prognosis of breast cancer patients remains to be explored.
KeywordsAdjuvant CMF Chemotherapy Breast Cancer Microarray Prediction Quantitative RT-PCR Recurrence
Supported by a grant to M. Kiechle and H. Hoefler from the BMBF (Federal Ministry of Education and Research), Germany, German National Genome Project (KR-S15T03).
- 2.Early Breast Cancer Trialists’ Collaborative Group (1992) Systemic treatment of early breast cancer by hormonal, cytotoxic, or immune therapy. 133 randomised trials involving 31,000 recurrences and 24,000 deaths among 75,000 women. Lancet 339:1–15Google Scholar
- 5.Levine MN, Bramwell VH, Pritchard KI, Norris BD, Shepherd LE, Abu-Zahra H et al (1998) Randomized trial of intensive cyclophosphamide, epirubicin, and fluorouracil chemotherapy compared with cyclophosphamide, methotrexate, and fluorouracil in premenopausal women with node-positive breast cancer. National Cancer Institute of Canada Clinical Trials Group. J Clin Oncol 16:2651–2658 PubMedGoogle Scholar
- 18.Ayers M, Symmans WF, Stec J, Damokosh AI, Clark E, Hess K et al (2004) Gene expression profiles predict complete pathologic response to neoadjuvant paclitaxel and fluorouracil, doxorubicin, and cyclophosphamide chemotherapy in breast cancer. J Clin Oncol 22:2284–2293. doi: 10.1200/JCO.2004.05.166 CrossRefPubMedGoogle Scholar
- 29.Niméus-Malmström E, Ritz C, Edén P, Johnsson A, Ohlsson M, Strand C et al (2006) Gene expression profiles and conventional clinical markers to predict distant recurrences for premenopausal breast cancer patients after adjuvant chemotherapy. Eur J Cancer 42:2729–2737. doi: 10.1016/j.ejca.2006.06.031 CrossRefPubMedGoogle Scholar
- 31.Martin M, Villar A, Sole-Calvo A, Gonzalez R, Massuti B, Lizon J et al (2003) Doxorubicin in combination with fluorouracil and cyclophosphamide (i.v. FAC regimen, day 1, 21) versus methotrexate in combination with fluorouracil and cyclophosphamide (i.v. CMF regimen, day 1, 21) as adjuvant chemotherapy for operable breast cancer: a study by the GEICAM group. Ann Oncol 14:833–842. doi: 10.1093/annonc/mdg260 CrossRefPubMedGoogle Scholar
- 35.Rody A, Karn T, Gätje R, Kourtis K, Minckwitz G, Loibl S et al (2006) Gene expression profiles of breast cancer obtained from core cut biopsies before neoadjuvant docetaxel, adriamycin, and cyclophoshamide chemotherapy correlate with routine prognostic markers and could be used to identify predictive signatures. Zentralbl Gynakol 128:76–81. doi: 10.1055/s-2006-921508 CrossRefPubMedGoogle Scholar
- 36.Rody A, Karn T, Solbach C, Gaetje R, Munnes M, Kissler S et al (2007) The erbB2+ cluster of the intrinsic gene set predicts tumor response of breast cancer patients receiving neoadjuvant chemotherapy with docetaxel, doxorubicin and cyclophosphamide within the GEPARTRIO trial. Breast 16:235–240. doi: 10.1016/j.breast.2007.02.006 CrossRefPubMedGoogle Scholar