Carbon Nanospheres Exert Antitumor Effects Associated with Downregulation of 4E-BP1 Expression on Prostate Cancer

Weimin Dong,1 Yong Luo,2 Guian Zhang,1 Hui Zhang,1 Yuxiang Liang,1 Yangjia Zhuo,1 Yingke Liang,1 Fen Zou,1 Weide Zhong1,3,4 1Department of Urology, Guangdong Key Laboratory of Clinical Molecular Medicine and Diagnostics, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou, Guangdong 510180, People’s Republic of China; 2Department of Urology, The Second People’s Hospital of Foshan, Affiliated Foshan Hospital of Southern Medical University, Foshan 528000, People’s Republic of China; 3Department of Urology, Huadu District People’s Hospital, Southern Medical University, Guangzhou 510800, People’s Republic of China; 4Urology Key Laboratory of Guangdong Province, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou Medical University, Guangzhou 510230, People’s Republic of ChinaCorrespondence: Weide Zhong; Fen ZouDepartment of Urology, Guangdong Key Laboratory of Clinical Molecular Medicine and Diagnostics, Guangzhou First People’s Hospital, School of Medicine, South China University of Technology, Guangzhou 510180, People’s Republic of ChinaTel +86 20-81048312Fax +86 20-8337332Email zhongwd2009@live.cn; zoufen2008@126.comIntroduction: Although carbon nanospheres (CNPs) are promising nanomaterials in cancer treatment, how they affect prostate cancer (PCa) remains unclear.Methods: In this study, scanning electron microscopy (SEM), X-ray diffraction (XRD), and Raman spectroscopy were used to confirm the successful synthesis of CNPs. CCK-8, flow cytometry, Transwell, wound healing, Western blot and immunohistochemistry (IHC) assays were performed to evaluate the antitumor effect of CNPs toward the two kinds of prostate cancer cell lines PC3 and DU145.Results: Our results showed that CNPs inhibited cell growth, invasion, and migration and induced apoptosis and autophagy in PCa cells. Multifactor detection of a single Akt phosphorylation pathway and Western blot results suggested the suppression of 4E-BP1 in PCa cells after incubation with CNPs. The results from animal experiments also suggested the antitumor effect of CNPs and reduced 4E-BP1 expression in PCa tissue samples from BALB/c nude mice administered a local subcutaneous injection of CNPs.Keywords: carbon nanosphere, prostate cancer, antitumor, 4E-BP1