Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 28, 2016; 22(12): 3341-3354
Published online Mar 28, 2016. doi: 10.3748/wjg.v22.i12.3341
Auphen and dibutyryl cAMP suppress growth of hepatocellular carcinoma by regulating expression of aquaporins 3 and 9 in vivo
Rui Peng, Guang-Xi Zhao, Jing Li, Yu Zhang, Xi-Zhong Shen, Ji-Yao Wang, Jian-Yong Sun
Rui Peng, Guang-Xi Zhao, Jing Li, Yu Zhang, Xi-Zhong Shen, Ji-Yao Wang, Jian-Yong Sun, Department of Gastroenterology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
Author contributions: Peng R and Zhang Y performed the majority of experiments; Zhao GX and Li J provided vital reagents and analytical tools and were also involved in editing the manuscript; Shen XZ, Wang JY and Sun JY co-ordinated and provided the collection of all the human material in addition to providing financial support for this work; Peng R and Sun JY designed the study and wrote the manuscript.
Supported by Science and Technology Commission of Shanghai, No. 13ZR1406700 and No. 13DZ1930908.
Institutional review board statement: The study was reviewed and approved by the Zhongshan Hospital of Fudan University Institutional Review Board.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of the Zhongshan Hospital (IACUC protocol number: SCXK2013-0016).
Conflict-of-interest statement: To the best of our knowledge, no conflict of interest exists.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at sun_jianyong1986@163.com. Participants gave informed consent for data sharing.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Jian-Yong Sun, PhD, Department of Gastroenterology, Zhongshan Hospital, Fudan University, 180 Fenglin Road, Shanghai 200032, China. sun_jianyong1986@163.com
Telephone: +86-10-64041990 Fax: +86-10-64041990
Received: November 15, 2015
Peer-review started: November 16, 2015
First decision: December 11, 2015
Revised: January 8, 2016
Accepted: January 30, 2016
Article in press: January 30, 2016
Published online: March 28, 2016
Abstract

AIM: To investigate whether the regulation of aquaporin 3 (AQP3) and AQP9 induced by Auphen and dibutyryl cAMP (dbcAMP) inhibits hepatic tumorigenesis.

METHODS: Expression of AQP3 and AQP9 was detected by Western blot, immunohistochemistry (IHC), and RT-PCR in HCC samples and paired non-cancerous liver tissue samples from 30 hepatocellular carcinoma (HCC) patients. A xenograft tumor model was used in vivo. Nine nude mice were divided into control, Auphen-treated, and dbcAMP-treated groups (n = 3 for each group). AQP3 and AQP9 protein expression after induction of xenograft tumors was detected by IHC and mRNA by RT-PCR analysis. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay and histological evaluation were used to detect apoptosis of tumor cells, and the concentration of serum α-fetoprotein (AFP) was measured using RT-PCR and an ELISA kit.

RESULTS: The volumes and weights of tumors decreased significantly in the Auphen- and dbcAMP-treated mice compared with the control mice (P < 0.01). The levels of AQP3 were significantly lower in the Auphen treatment group, and levels of AQP9 were significantly higher in thedbcAMP treatment mice than in the control mice (P < 0.01). The reduction of AQP3 by Auphen and increase of AQP9 by dbcAMP in nude mice suppressed tumor growth of HCC, which resulted in reduced AFP levels in serum and tissues, and apoptosis of tumor cells in the Auphen- and dbcAMP-treated mice, when compared with control mice (P < 0.01). Compared with para-carcinoma tissues, AQP3 expression increased in tumor tissues whereas the expression of AQP9 decreased. By correlating clinicopathological and expression levels, we demonstrated that the expression of AQP3 and AQP9 was correlated with clinical progression of HCC and disease outcomes.

CONCLUSION: AQP3 increases in HCC while AQP9 decreases. Regulation of AQP3 and AQP9 expression by Auphen and dbcAMP inhibits the development and growth of HCC.

Keywords: Hepatocellular carcinoma, Nude mice, Auphen, Dibutyryl cAMP, Aquaporin 3, Xenograft tumor model, Aquaporin 9

Core tip: This is the first study intending to evaluate the antioncogenic effects of Auphen and dibutyryl cAMP (dbcAMP) in vivo and investigate whether their underlying mechanism involves regulating aquaporin 3 (AQP3) and AQP9 expression. An in-depth description of AQP3 and AQP9 regulation by Auphen and dbcAMP will provide a better understanding of the mechanisms of hepatocarcinogenesis, which could be used in the development of novel therapeutic drugs. This work further confirms the significance of AQP-driven hepatocarcinogenesis, emphasizing the importance of both basic and clinical knowledge of the roles of aquaporins in hepatocellular carcinoma.