CCDC6 and urinary bladder carcinoma: However, by silencing CCDC6 in bladder cancer cells and upon treatment with low dose of RRx-001, we observed only a weak activation of γH2AX, compared to controls, that suggested cells tolerance to ROS, even if at the RRx-001 dose of 5 μM the γH2AX activation showed a feeble recover, regardless of the CCDC6 deficiency (Fig. 3f).