Cell growth features. (A) Cells were maintained in adherent dishes for up to 168 h in CMRL medium containing 5.6 mM glucose and 5% FCS. After 24 h, 48 h, 72 h, 120 h and 168 h, cells were harvested and counted. Data are presented as the mean of three independent experiments (n = 3 for each experiment) ± s.d. Doubling times were calculated from these data using PRISM4 ® software. (B) Cells were seeded, in triplicate, in 24 multiwell plates. After 24 h, cells were serum starved for 24 h and then subjected to a 48 h treatment with either: EGF; (C) IGF-1, a vs b, c, d, e; b vs c: p < 0.001; (D) rhPRL, a vs c, d; b vs c, d: p < 0.001;(E) a combination of IGF-1 and rhPRL, a vs b, c; b vs d; c vs d: p < 0.001; or their corresponding vehicles. Cells were then harvested, fixed and counted. Data are presented as the mean of three independent experiments ± SEM.