XRCC6 and prostate carcinoma: Binding with IKKα; inhibition of NF-ĸB/p65 activity; inhibition of apoptosis proteins and Ku70-Bax interaction; inhibition of tumor suppressor ER-β degradation; inhibition of class I HDACs expression; inhibition of ABCB1 expression and sensitivity improvement of docetaxel-resistant prostate cancer cells to docetaxel treatment.