Prolactin-induced mouse mammary carcinomas model estrogen resistant luminal breast cancer

Breast Cancer Research

Table 1 Characteristics of PRL-induced carcinomas by histotype

	Glandular	Solid	Papillary	Adenosquamous	Carcinosarcoma
N	10	3	10	3	4
ERα¹	10.0 ± 3.6 ^a	4.4 ± 2.9 ^b	21.1 ± 8.1	32.2 ± 10.2 ^a,b	8.2 ± 3.0
PR¹	1.5 ± 1.0	0.3 ± 0.2	13.8 ± 6.3	2.4 ± 1.4	0
pStat5¹	49.0 ± 8.13^a,b	66.6 ± 12.2 ^c,d,e	29.4 ± 18.7 ^c	23.9 ± 5.25 ^a,d	5.7 ± 1.9 ^b,e
c-Fos¹	18.3 ± 2.8 ^a	15.0 ± 2.5^b,c	17.6 ± 3.7 ^d	30.5 ± 4.4 ^a,b	25.2 ± 3.2 ^c,d
S phase¹	15.6 ± 1.7	15.0 ± 2.5	18.0 ± 2.0	14.7 ± 1.3	15.5 ± 2.2
Apoptotic¹	2.1 ± 0.3	3.6 ± 1.1	2.2 ± 0.3	1.9 ± 0.4	1.1 ± 0.2
pERK1/2²	70% strong, 10% weak stromal; 30% epithelial	100% strong stromal	90% strong stromal; 10% epithelial	100% strong stromal	100% strong stromal & epithelial
pAKT²	50% epithelial; 20% stromal; 30% negative	67% epithelial; 33% negative	70% epithelial; 10% stromal; 20% negative	33% epithelial & stromal; 67% negative	75% epithelial; 25% negative

¹% tumor epithelial cells that are positive, mean ± s.e.m (see Materials and methods). Same lower case letters indicate significant differences between histotypes (P < 0.05; Students t-test).
²% of tumors of each histotype that displayed strong staining in different locations (stroma, epithelium, or both) as indicated.
ERα, estrogen receptor alpha; ERK, extracellular signal regulated kinase; PR, progesterone receptor; PRL, prolactin; Stat5, signal transducer and activator of transcription 5.

ISSN: 1465-542X