Multifunctional antioxidant nanoliposome-mediated delivery of PTEN plasmids restore the expression of tumor suppressor protein and induce apoptosis in prostate cancer cells Sanjay Singh , Raghu Asal, Stuti Bhagat Division of Biological and Life Science, School of Arts and Science, Ahmedabad University, Ahmedabad, 380009, Gujarat, India Received 25 May 2018; revised 29 June 2018; accepted 12 July 2018 Published online 00 Month 2018 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/jbm.a.36510 Abstract: Prostate cancer is the second leading cause of cancer death in men and about one in nine will be diagnosed in his life- time. Loss of PTEN has been considered as one of the major fac- tors leading to the origin of prostate cancer through modulating PI3K/AKT signaling pathways. In this study, we have prepared a multifunctional antioxidant nanoliposome containing PTEN plas- mid and cerium oxide nanoparticles (CeNPs). The efficient deliv- ery of PTEN plasmid to human prostate cancer cells (PC-3) leads to restoration of the expression of lost PTEN protein in the cell cytoplasm. The delivered superoxide dismutase (SOD)-mimetic CeNPs were also found to decrease the cytoplasmic free radical levels in prostate cancer cells. The above two activities induced DNA fragmentation and micronucleus formation in prostate cancer cells. Furthermore, it was also found that these multifunc- tional antioxidant nanoliposomes inhibit the PI3K/AKT signaling pathway to negatively regulate the cell viability of prostate cancer cells. The mRNA expression pattern of other relevant proteins predominantly involved in cancer cell proliferation and apoptosis suggested that the high PTEN expression could control the syn- thesis of oncogenic proteins. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 00A: 000–000, 2018. Key Words: multifunctional nanoparticles, PTEN plasmid, pros- tate cancer, cerium oxide nanoparticles, gene delivery, nanoli- posomes, tumor suppressor protein How to cite this article: Singh S, Asal R, Bhagat S. 2018. Multifunctional antioxidant nanoliposome-mediated delivery of PTEN plasmids restore the expression of tumor suppressor protein and induce apoptosis in prostate cancer cells. J Biomed Mater Res Part A. 2018:00A:1–13. INTRODUCTION There has been a significant evolution in prostate cancer treatment paradigms in recent past; however, it remains a challenging public health burden. In the year 2012, a total of about 1 million new cases and about 0.31 million deaths related to prostate cancer were reported globally. 1 Despite the recent developments in the area of advanced molecular biology and cell biology, which have produced new bio- markers and targets responsible for the origin of prostate cancer, the successful treatment of this disease has not been realized so far. The possible obstacles could be the identifica- tion of biomarkers at the very early stage of the prostate cancer genesis, high payload delivery of the drugs/agents needed for the inhibition of cancer cell proliferation. Among the identified targets, loss of PTEN (phosphatase and tensin homolog deleted on chromosome 10), a well- known tumor suppressor gene, has been reported to be one of the major factors involved in the origin of prostate cancer. PTEN encodes phosphatases, which functions as an antago- nist of PI3K (phosphatidylinositol 3-kinase) and AKT (protein kinase B) activation. 2 PTEN, along with PI3K/AKT signaling pathway, regulates multiple biological processes including apoptosis and cell proliferation. Most of the com- ponents of this signaling pathway are reported to be involved in the development of several types of cancers including prostate. 3 Several methods have been reported for the loss of PTEN activity, which includes mutations, dele- tions, or silencing of promoter methylation in prostate can- cers. 4,5 PTEN loss leads to the elevation in the expression levels of AKT-3, thereby inducing cell proliferation, anti-apo- ptosis, and migration through multiple downstream pro- cesses. In this context, Xu et al. have reported that a transient overexpression of PTEN causes inhibition in prolif- eration in PTEN-deficient cell culture models of many cancer cell lines. 6–9 Therefore, on the basis of these findings, it can be concluded that PTEN is needed for normal cellular pro- cesses and loss of PTEN function leads to the carcinogenesis. Nanomaterials have shown tremendous potential to develop smart nanocarriers which can deliver the active anticancer molecules at the desired site of the tumor. Among Additional Supporting Information may be found in the online version of this article. Correspondence to: S. Singh; e-mail: sanjay.singh@ahduni.edu.in Contract grant sponsor: Department of Science and Technology - Science and Engineering Research Board (SERB); contract grant number: ILS/ SERB/2015-16/01 © 2018 WILEY PERIODICALS, INC. 1