CRISPR/Cas9-mediated gene knockout of NANOG and NANOGP8 decreases the malignant potential of prostate cancer cells

// Norihiko Kawamura 1, 2 , Keisuke Nimura 1 , Hiromichi Nagano 1 , Sohei Yamaguchi 1 , Norio Nonomura 2 , Yasufumi Kaneda 1 1 Division of Gene Therapy Science, Osaka University Graduate School of Medicine, Suita, Osaka 565–0871, Japan 2 Department of Urology, Osaka University Graduate School of Medicine, Suita, Osaka 565–0871, Japan Correspondence to: Keisuke Nimura, e-mail: nimura@gts.med.osaka-u.ac.jp Yasufumi Kaneda, e-mail: kaneday@gts.med.osaka-u.ac.jp Keywords: NANOG, NANOGP8, gene knockout, CRISPR/Cas9, prostate cancer Received: March 31, 2015      Accepted: June 03, 2015      Published: June 15, 2015 ABSTRACT NANOG expression in prostate cancer is highly correlated with cancer stem cell characteristics and resistance to androgen deprivation. However, it is not clear whether NANOG or its pseudogenes contribute to the malignant potential of cancer. We established NANOG - and NANOGP8 -knockout DU145 prostate cancer cell lines using the CRISPR/Cas9 system. Knockouts of NANOG and NANOGP8 significantly attenuated malignant potential, including sphere formation, anchorage-independent growth, migration capability, and drug resistance, compared to parental DU145 cells. NANOG and NANOGP8 knockout did not inhibit in vitro cell proliferation, but in vivo tumorigenic potential decreased significantly. These phenotypes were recovered in NANOG - and NANOGP8 -rescued cell lines. These results indicate that NANOG and NANOGP8 proteins are expressed in prostate cancer cell lines, and NANOG and NANOGP8 equally contribute to the high malignant potential of prostate cancer.