Androgen Deprivation Therapy Potentiates the Efficacy of Vascular Targeted Photodynamic Therapy of Prostate Cancer Xenografts. Androgen Deprivation Therapy Potentiates the Efficacy of Vascular Targeted Photodynamic Therapy of Prostate Cancer Xenografts

WST11 vascular targeted photodynamic therapy (VTP) is a local ablation approach relying upon rapid, free radical-mediated destruction of tumor vasculature. A phase III trial showed that VTP significantly reduced disease progression when compared to active surveillance in patients with low-risk prostate cancer (PCa). The aim of this study was to identify a druggable pathway that could be combined with VTP to improve its efficacy and applicability to higher risk PCa tumors. Overall design: LNCaP-AR cells were grafted into intact mice to establish tumors. The mice were then treated with WST11 at 9 mg/kg, and tumors were focally treated with VTP using 100 mW laser fluence. Tumors were collected at 3, 6, or 24 hr, 1 week and 8.5 weeks post VTP. Mice with control tumors received WST11, but were not exposed to the laser and were matched to the 1 and 8.5 week treatment groups. RNA was isolated from 36 total tumors for microarray hybridization, with 4-8 replicates per group. 32 samples were used for analysis (n=4 from 24 hr VTP removed during quality control).