Figure 2

PRL-induced carcinomas demonstrate an inverse relationship between nuclear phosphorylated Stat 5 (pStat 5) and AP-1 proteins. (a) Nuclear pStat 5 staining in a glandular adenocarcinoma. (b) c-Fos expression in a glandular adenocarcinoma. (c) c-Jun staining in a glandular adenocarcinoma. (d) The proportion of tumor cells that express ERα and nuclear pStat5 is not correlated. (e) Carcinomas exhibit a significantly negative correlation between the proportion of cells that contain nuclear pStat 5 and c-Fos (P < 0.0001, R = -0.63). ERα, pStat 5, c-Fos and c-Jun expression were evaluated and quantitated as described in Materials and Methods. Each box represents a single carcinoma that arose in a different NRL-PRL nonparous female. Correlations were determined using Spearman's non-parametric test. (f) Expi mRNA is significantly increased in the adenocarcinomas expressing highest pStat5, compared to the lowest 5 (mean ± s.e.m., N = 5; *, P = 0.003). (g) Mmp9 mRNA is significantly decreased in the adenocarcinomas expressing highest pStat5, compared to the lowest 5 (mean ± s.e.m., N = 5; *, P = 0.03). (f, g) Transcript levels were measured using qRT-PCR as described in Materials and Methods. Original magnification: a, b, c, 400x.