PTEN and Familial prostate cancer: Furthermore, ARID4B promoter-driven luciferase reporter gene assays showed that knockdown of PTEN activated the ARID4B promoter in the PTEN-intact prostate cancer cell line DU145 and cervical cancer cell line HeLa (Fig. 5f and Supplementary Fig. 10b), whereas overexpression of PTEN suppressed the ARID4B promoter activity (Fig. 5g).