Genomic Profiling of Breast Cancer (BC) in Mali by Oligonucleotide Comparative Genomic Hybridization (CGH) Array.

Background : Epidemiological studies suggest that BC in Africa exhibit specific biological characteristics as compared to BC from US/Europe. In order to identify therapeutic targets that would be specific from Africa, we analyzed 28 samples from Mali by high resolution CGH array, and compared gene gains/losses to the ones observed in USA [Andre F et al, Clin Cancer Res, 2009] Patients and methods : 71 paraffin-embedded samples of invasive BC from patients treated by surgery at Bamako were retrieved, 28 of them (from 2 pts stage 1; 13 pts stage 2; 11 pts stage 3 and 2 pts stage 4) were eligible for CGH array (1) (Agilent, 4*44K) (cancer cells>50%; undamaged DNA >1µg).Results were compared to 106 samples from MD Anderson, profiled in the sample genomic platform using the same array (1) Results : The median age was 49 year old. Twenty-one samples (75%) were ER-negative. No difference was observed regarding the frequency of gene gains in 17q12-21 (ERBB2) nor 8p11-12 (FGFR1). Six regions were more frequently gained in BC from Mali, as compared to those from US (FDR Conclusion: BC from Mali present some candidate specific targetable alterations as gains of Abl1, bcr and pdgf-B. FISH and IHC are being done in order to validate targets.Additional high throughput analyses will be performed to characterize such tumors, including virus arrays, exon arrays and hot spot mutations. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3059.