Basic Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Apr 28, 2015; 21(16): 4864-4874
Published online Apr 28, 2015. doi: 10.3748/wjg.v21.i16.4864
Inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma
Ke-Qi Han, Xue-Qun He, Meng-Yu Ma, Xiao-Dong Guo, Xue-Min Zhang, Jie Chen, Hui Han, Wei-Wei Zhang, Quan-Gang Zhu, Hua Nian, Li-Jun Ma
Ke-Qi Han, Xue-Qun He, Meng-Yu Ma, Xiao-Dong Guo, Xue-Min Zhang, Jie Chen, Hui Han, Wei-Wei Zhang, Department of Oncology, Shanghai Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai 200336, China
Quan-Gang Zhu, Hua Nian, Department of Pharmacy, Shanghai Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai 200336, China
Li-Jun Ma, Department of Oncology, Tongren Hospital of Shanghai Jiaotong University School of Medicine, Shanghai 200336, China
Author contributions: Han KQ and Ma LJ designed and performed the experiments; He XQ, Ma MY, Guo XD, Zhang XM, Chen J, Han H, Zhang WW, Zhu QG and Nian H provided vital reagents and analytical tools and were also involved in editing the manuscript; Han KQ and He XQ wrote the paper.
Supported by Natural Science Foundation of China, No. 81072954.
Ethics approval: The study was reviewed and approved by the Institutional Review Board of Shanghai University of Traditional Chinese Medicine.
Institutional animal care and use committee: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee of Shanghai University of Traditional Chinese Medicine (No. 20130413).
Conflict-of-interest: All the authors declare that they have no conflicts of interest.
Data sharing: No additional data are available.
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: Dr. Li-Jun Ma, Department of Oncology, Tongren Hospital of Shanghai Jiaotong University School of Medicine, 1111 Xianxia Road, Shanghai 200336, China. ljma5@hotmail.com
Telephone: +81-21-62909911
Received: October 9, 2014
Peer-review started: October 11, 2014
First decision: October 29, 2014
Revised: November 24, 2014
Accepted: December 14, 2014
Article in press: December 16, 2014
Published online: April 28, 2015
Processing time: 200 Days and 16.3 Hours
Abstract

AIM: To study the inflammatory microenvironment and expression of chemokines in hepatocellular carcinoma (HCC) in nude mice.

METHODS: CBRH-7919 HCC cells were injected into the subcutaneous region of nude mice. Beginning two weeks after the challenge, tumor growth was measured every week for six weeks. The stromal microenvironment and inflammatory cell infiltration was assessed by immunohistochemistry in paired tumor and adjacent peritumoral samples, and macrophage phenotype was assessed using double-stain immunohistochemistry incorporating expression of an intracellular enzyme. A chemokine PCR array, comprised of 98 genes, was used to screen differential gene expressions, which were validated by Western blotting. Additionally, expression of identified chemokines was knocked-down by RNA interference, and the effect on tumor growth was assessed.

RESULTS: Inflammatory cell infiltrates are a key feature of adjacent peritumoral tissues with increased macrophage, neutrophil, and T cell (specifically helper and activated subsets) infiltration. Macrophages within adjacent peritumoral tissues express inducible nitric oxide synthase, suggestive of a proinflammatory phenotype. Fifty-one genes were identified in tumor tissues during the progression period, including 50 that were overexpressed (including CXCL1, CXCL2 and CXCL3) and three that were underexpressed (CXCR1, Ifg and Actb). RNA interference of CXCL1 in the CBRH-7919 cells decreased the growth of tumors in nude mice and inhibited expression of CXCL2, CXCL3 and interleukin-1β protein.

CONCLUSION: These findings suggest that CXCL1 plays a critical role in tumor growth and may serve as a potential molecular target for use in HCC therapy.

Keywords: Chemokines; Gene expression profile; Hepatocellular carcinoma; PCR array; RNA interference

Core tip: An orthotopic transplantation tumor model of hepatocellular carcinoma (HCC) with CBRH-7919 cells was established. Inflammatory cell infiltration and macrophage phenotype were assessed by immunohistochemistry. A chemokine PCR array was used to identify differentially expressed genes, and tumor growth was assessed after knockdown with RNA interference. This study describes the inflammatory microenvironment and differential expression of chemokines in hepatocellular carcinoma. The data suggest that CXCL1 plays a critical role in tumor growth and may serve as a potential molecular target for use in HCC therapy.