Research Paper Volume 12, Issue 24 pp 24671—24692

Progesterone receptor isoform-dependent cross-talk between prolactin and fatty acid synthase in breast cancer

Figure 4. Pharmacological blockade of FASN activity modifies autocrine prolactin secretion in a PR-dependent manner. (A). Top. Autocrine prolactin secretion levels in the extracellular milieu of estradiol-depleted cells cultured in the absence or presence of graded concentrations of C75 in 0.5% CCS for 48 h were determined by a commercially available EASIA kit. Data are means (columns) ± S.D. (bars) from three independent experiments performed in duplicate. Secreted amounts of prolactin in C75-treated cells were compared with those in vehicle-treated control cells (* P < 0.05; ** P < 0.005). Bottom. Cell lysates strictly obtained from the same experimental replicates employed in A were subjected to immunoblotting for PRLR protein expression. β-actin was used to control for protein loading and transfer. Figure shows a representative immunoblot analysis. Similar results were obtained in 3 independent experiments. (B). Autocrine IL-6 levels in the extracellular milieu of estradiol-depleted cells cultured in the absence or presence of 10 μg/mL C75 in 0.5% CCS for 48 h were determined by a commercially available ELISA kit. Secreted amounts of IL-6 in C75-treated cells were compared with those in vehicle-treated control cells (** P < 0.005).