Figure 3.

In vivo validation of dox-mediated induction of sARE-like AR target genes, and inhibition of cARE-like AR target genes. (A) Mouse xenograft tumor growth was assessed following dox treatment. 10⁶ LAPC4 cells were inoculated into flanks of castrated mice bearing testosterone pellets that maintained human physiologically relevant levels of the hormone. Tumors were followed by palpation and measured by calipers, with volume calculated as (length × width²)/2. Tumor volume change (top) and average tumor volume (bottom) represent tumor growth in mice treated for 3 weeks with either no (vehicle control – veh, n = 7), low (n = 12), or medium (med, n = 12)) dox doses (0, 0.5, 1.7 mg/kg, respectively). Growth was heterogeneous, but as shown on the lower left, trended to slower growth for the low dox dose, compared to untreated or treated with higher dox doses. (B) Total mRNA extracted from xenograft tumors at endpoint was subjected to Q-RT-PCR for the mRNAs of sARE responsive genes SGK1, SARG (C1orf116) and NKX3-1, cARE responsive genes PSA (KLK3), FKBP5 and TMPRSS2, as well as oncogenic transcription factors AR, MYC, and GR (NR3C1). Fold-changes were normalized to β-actin and data plotted relative to the average of untreated control with error bars representing SD (* indicates P < 0.05).