Parity-related molecular signatures and breast cancer subtypes by estrogen receptor status

Table 1 Differences in study design, experimental approaches and sample characteristics ^a

Study demographics	PVLSI	SHL^b[12]	UICH^b[24]	PBCS cancer-adjacent normal tissue	PBCS tumor tissue
Cancer status	Cancer-free	Cancer-free	Cancer-free	Breast cancer	Breast cancer
Tissue source	Fresh whole tissue	Core needle biopsies	Microdissected FFPE tissue	Fresh whole tissue	Fresh whole tissue
Tissue enrichment	Stroma	Epithelial and stromal	Epithelial	Stroma	Epithelial
Gene expression platform	Agilent 4 × 44K	GeneChip U133Plus 2.0	RT-PCR of 64 genes	Agilent 4 × 44K	Illumina
Samples
Total	130	107	24	150
ER+, n (%)	N/A	N/A	N/A	117 (78%)
Parous, n (%)	76 (58%)	67 (63%)	11 (46%)	119 (79%)
Premenopausal, n (%)	84 (65%)	0 (0%)	24 (100%)	41 (27%)
Mean age (±SD), yr	37 (13)	60 (5)	29 (6)	56 (10)
Mean BMI (±SD)	30^c (6)	25 (4)	–	28 (5)

^a%, Percentage for categorical variables; BMI, Body mass index; FFPE, Formalin-fixed, paraffin-embedded; N/A, Not applicable; PBCS, Polish Breast Cancer Case–Control Study; PVLSI, Samples obtained from normal breast tissue of 130 women who underwent reduction mammoplasty surgery at Baystate Medical Center in Springfield, MA, USA, and banked at the Pioneer Valley Life Sciences Institute; SD, Standard deviation for continuous variables; SHL, Normal breast samples from 107 postmenopausal healthy volunteers recruited at the Sunderby Hospital in Luleå, Sweden; UICH, Mammoplasty benign biopsy specimens from 24 premenopausal women from the University of Illinois at Chicago Hospital. ^bFrom previously published, parity-related gene expression signatures in healthy women [12, 24]. ^cThere were 56 (43%) missing BMI values in the PVLSI group.

ISSN: 1465-542X