Liver Cancer
Copyright ©2006 Baishideng Publishing Group Co., Limited. All rights reserved.
World J Gastroenterol. Nov 7, 2006; 12(41): 6614-6619
Published online Nov 7, 2006. doi: 10.3748/wjg.v12.i41.6614
Development and characterization of multidrug resistant human hepatocarcinoma cell line in nude mice
Bao-Jin Zhai, Ze-Yong Shao, Chun-Liang Zhao, Kai Hu, Feng Wu
Bao-Jin Zhai, Ze-Yong Shao, Chun-Liang Zhao, Kai Hu, Feng Wu, Clinical Center for Tumor Therapy of 2nd Affiliated Hospital, and Institute of Ultrasonic Engineering in Medicine, Chongqing University of Medical Sciences, Chongqing, China
Supported by National Natural Science Foundation of China, No. 30171060
Correspondence to: Dr. Feng Wu, Box 153, Institute of Ultra-sonic Engineering in Medicine, Chongqing University of Medical Sciences, 1 Medical College Road, Chongqing 400016, China. mfengwu@yahoo.com
Telephone: +86-23-63737940 Fax: +86-23-68701154
Received: July 27, 2006
Revised: August 12, 2006
Accepted: October 6, 2006
Published online: November 7, 2006
Abstract

AIM: To establish a multidrug resistant (MDR) cell sub-line from the human hepatocarcinoma cell line (HepG2) in nude mice.

METHODS: HepG2 cell cultures were incubated with increasing concentrations of adriamycin (ADM) to develop an ADM-resistant cell subline (HepG2/ADM) with cross-resistance to other chemotherapeutic agents. Twenty male athymic BALB/c-nu/nu mice were randomized into HepG2/nude and HepG2/ADM/nude groups (10 in each group). A cell suspension (either HepG2 or HepG2/ADM) was injected subcutaneously into mice in each group. Tumor growth was recorded, and animals were sacrificed 4-5 wk after cell implantation. Tumors were prepared for histology, and viable tumor was dispersed into a single-cell suspension. The IC50 values for a number of chemotherapeutic agents were determined by 2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt (MTT) assay. Rhodamine-123 retention/efflux and the level of resistance-associated proteins were determined by flow cytometry. The mRNA expression of mdr1, mrp and lrp genes was detected using reverse transcriptase polymerase chain reaction (RT-PCR) in HepG2/nude and HepG2/ADM/nude groups.

RESULTS: The appearances of HepG2/nude cells were slightly different from those of HepG2/ADM/nude cells. Similar tumor growth curves were determined in both groups. A cross-resistance to ADM, vincristine, cisplatin and 5-fluorouracil was seen in HepG2/ADM/nude group. The levels of P-glycoprotein and multidrug resistance-associated proteins were significantly increased. The mRNA expression levels of mdr1, mrp and lrp were higher in HepG2/ADM/nude cells.

CONCLUSION: ADM-resistant HepG2 subline in nude mice has a cross resistance to chemotherapeutic drugs. It may be used as an in vivo model to investigate the mechanisms of MDR, and explore the targeted approaches to overcoming MDR.

Keywords: Hepatocarcinoma; Multidrug resistance; Adriamycin; Model; Nude mouse