PURPOSE: Despite recent advances in the treatment of metastatic prostate cancer, survival rates are low and treatment options are limited to chemotherapy and hormonal therapy. Although ionizing radiation is used to treat localized and metastatic prostate cancer, the most efficient use of radiotherapy is yet to be defined. Our purpose was to determine in vitro the potential benefit to be gained by combining radiation treatment with cytotoxic drugs. MATERIALS AND METHODS: Inhibitors of DNA repair and heat shock protein 90 and an inducer of oxidative stress were evaluated in combination with x-radiation for their capacity to reduce clonogenic survival and delay the growth of multicellular tumor spheroids. RESULTS: Inhibitors of the PARP DNA repair pathway, olaparib and rucaparib, and the HSP90 inhibitor 17-DMAG, enhanced the clonogenic cell kill and spheroid growth delay induced by x-radiation. However, the oxidative stress-inducing drug elesclomol failed to potentiate the effects of x-radiation. PARP inhibitors arrested cells in the G2/M phase when administered as single agents or in combination with radiation, whereas elesclomol and 17-DMAG did not affect radiation-induced cell cycle modulation. CONCLUSIONS: These results indicate that radiotherapy of prostate cancer may be optimized by combination with inhibitors of PARP or HSP90, but not elesclomol.
Rae, C. and Mairs, R. J.
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Xstrahl to Highlight Superficial and Orthovoltage Radiotherapy Solutions for Skin Cancer and Selective Benign Conditions at ACRO Summit 2025 in Las Vegas
Xstrahl, a global leader in the delivery of superficial radiation therapy devices and preclinical radiation research systems, will demonstrate Xstrahl 200, a modern orthovoltage radiotherapy solution for treating superficial lesions, skin cancers, and selective benign conditions. Visit Xstrahl at booth 220 at the ACRO Summit 2025 – The Radiation Oncology Summit located at Planet Hollywood, Las Vegas, NV from March 12-15, 2025.
