Promising therapeutic efficacy of a novel reduced expression in immortalized cells/dickkopf-3 expressing adenoviral vector for hepatocellular carcinoma.
OBJECTIVE
Reduced expression in immortalized cells (REIC)/dickkopf-3 (Dkk-3) is a tumor suppressor gene that is downregulated in various cancers. In our previous study of prostate cancer, the REIC/Dkk-3-expressing adenoviral vector (Ad-REIC) was found to induce cancer-selective apoptosis. This study recently developed a novel super gene expression (SGE) system and used this system to re-construct an Ad-REIC vector, termed the Ad-SGE-REIC, to achieve more effective therapeutic outcomes. In this study, the therapeutic effects of Ad-SGE-REIC on hepatocellular carcinoma (HCC) was assessed.


METHODS
Human HCC cell lines (HLE, Huh7, HepG2, HLF, SK-Hep1, and PLC), human HCC tissues, and mouse HCC cell line (Hepa1-6) were used in this study. REIC/Dkk-3 expression was assessed by immunoblotting and immunohistochemistry. The relative cell viability and the apoptotic effect were examined in vitro, and the anti-tumor effects of Ad-SGE-REIC treatment were analyzed in the mouse xenograft model. This study additionally assessed anti-tumor immunological effects on the immunocompetent mice.


RESULTS
REIC/Dkk-3 expression was decreased in HCC cell lines and HCC tissues. Ad-SGE-REIC reduced cell viability and induced apoptosis in HCC cell lines (HLE and Huh7), inhibited tumor growth in the mouse xenograft model, and demonstrated in vivo anti-cancer immunostimulatory effects on the HCC cell line (Hepa1-6).


CONCLUSIONS
Ad-SGE-REIC treatment not only enhanced cell killing effects in vitro but also elicited significant therapeutic effects, with tumor growth suppression, in vivo. REIC/Dkk-3 gene therapy using Ad-SGE-REIC potentially represents an innovative new therapeutic tool for HCC.
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hiroaki
H
Sawahara
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hidenori
H
Shiraha
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Daisuke
D
Uchida
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hironari
H
Kato
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Ryo
R
Kato
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Atsushi
A
Oyama
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Teruya
T
Nagahara
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.|Department of General Medicine, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Masaya
M
Iwamuro
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Shigeru
S
Horiguchi
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Koichiro
K
Tsutsumi
Department of Internal Medicine, Okayama Saiseikai General Hospital, Okayama, Japan.
Mari
M
Mandai
Department of Surgery, Okayama Saiseikai General Hospital, Okayama, Japan.
Tetsushige
T
Mimura
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Nozomu
N
Wada
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Yasuto
Y
Takeuchi
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Kenji
K
Kuwaki
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hideki
H
Onishi
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Shinichiro
S
Nakamura
Department of Urology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.|Department of Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan.
Masami
M
Watanabe
Department of Cell Biology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Masakiyo
M
Sakaguchi
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Akinobu
A
Takaki
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Kazuhiro
K
Nouso
Department of Gastroenterological Surgery, Transplant, and Surgical Oncology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Takahito
T
Yagi
Department of Urology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.|Department of Center for Innovative Clinical Medicine, Okayama University Hospital, Okayama, Japan.
Yasutomo
Y
Nasu
Department of Innovation Center Okayama for Nanobio-Targeted Therapy, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hiromi
H
Kumon
Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.
Hiroyuki
H
Okada
D048868:Adaptor Proteins, Signal Transducing; D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D006528:Carcinoma, Hepatocellular / Q000473:pathology / Q000628:therapy*; D045744:Cell Line, Tumor; D018925:Chemokines; D004195:Disease Models, Animal; D015870:Gene Expression; D016147:Genes, Tumor Suppressor; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000235:genetics* / Q000627:therapeutic use*; D056945:Hep G2 Cells; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics* / Q000378:metabolism / Q000627:therapeutic use*; D008113:Liver Neoplasms / Q000473:pathology / Q000628:therapy*; D008807:Mice, Inbred BALB C; D009368:Neoplasm Transplantation
D048868:Adaptor Proteins, Signal Transducing; D018925:Chemokines; C498624:DKK3 protein, human; D036341:Intercellular Signaling Peptides and Proteins
REIC; dickkopf-3; gene expression; gene therapy; hepatocellular carcinoma