Figure 3. Influence of the tumor microenvironment on radiation response.

(A) Tumors were treated with vehicle (control) or olaparib (6 or 7 days, 50mg/kg, BID, ip) in vivo followed by mock irradiation or one fraction of 12 Gy. Twenty-four hours later tumors were harvested and plated as single cell suspension. Clonogenic survival was analyzed on the 11th day after plating with an increased clonogenic cell kill in the neoadjuvantly treated tumors. (B) Tumors were treated with vehicle (control) or olaparib (6 or 7 days, 50mg/kg, BID, ip) in vivo followed by harvesting, plating and in vitro mock or 12 Gy dose of radiation. There was no significant difference in radiation response between the control and neoadjuvantly treated tumors 11 days after plating.