[126] A Survey of 45 Biomarkers for Basal-Like Breast Cancer.

Jennifer R Choo, Dongxia Gao, Samuel Leung, Christine Chow, Sherman YH Lau, Jinjin Cheng, Torsten O Nielsen. University of British Columbia, Vancouver, Canada

Background: Basal-like breast cancer was originally identified by gene expression profiling, and it is associated with high-risk disease not responsive to available targeted therapies. Numerous biomarkers for basal-like breast cancer have been proposed. The following study performs a comprehensive immunohistochemical investigation of proposed biomarkers against a gene expression profile gold standard.
Design: Parallel analysis of 45 proposed basal-like biomarkers from literature and gene expression profile data was done on a breast cancer tissue microarray of cases (n = 122) where subtype was previously assigned by a PAM50 gene expression profile gold standard. Twenty-five of the 45 biomarkers were significantly associated with basal-like breast cancer (Table 1). Statistical analysis was performed using the Fisher's exact test corrected for multiple comparisons.
Results:

Table 1

Biomarker*	Sensitivity	Specificity	Accuracy**
α-B-crystallin	42	92	73
Caveolin 2	19	98	65
Ck 14	27	100	67
Ck 17	51	92	75
Ck 5	72	90	82
Ck 5/6	50	87	72
c-Kit	43	96	75
Claudin 4	66	73	72
Cyclin E	72	66	77
EGFR	41	94	72
Fascin	59	93	77
IMP3	25	100	70
ki67	94	50	65
Moesin	71	84	82
Negative ER	92	67	72
Negative PR	92	46	57
Nestin	55	95	83
NGFR	22	100	67
p16	81	82	80
p53	55	81	70
P-cadherin	80	61	72
PPH3	94	58	73
S100A9	63	82	75
Skp2	62	79	73
TRIM29	72	86	80

*Alphabetical order, adjusted p <.05; **Based on cases with complete data for all 45 biomarkers.

Biomarkers with a statistically non-significant association (adjusted p >.05) to basal-like breast cancer included: anilin, CAIX, caveolin 1, CD44, CD44v6, FABP7, FOXC1, negative Her2, Integrin β4, laminin5, loss of BRCA1, Met, negative p27, p63, p-glycoprotein, pS6rp, negative PTEN, SMAD4, VEGF and vimentin.
Conclusions: Nestin is the most accurate single biomarker for basal-like breast cancer among the 45 tested against a gene expression profile gold standard. These results can be used to build an optimal multi-biomarker panel, for which validation on an independent sample cohort would be required.
Category: Breast

Monday, February 28, 2011 9:30 AM

Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 32, Monday Morning