Dual Therapeutic Effects of Interferon-α Gene Therapy in a Rat Hepatocellular Carcinoma Model With Liver Cirrhosis

Abstract

Human hepatocellular carcinoma (HCC) often arises from a background of liver cirrhosis. Therefore, in order to develop therapeutic strategies for HCC, an animal model bearing multifocal liver tumors accompanied by liver cirrhosis is a preferred experimental setting. In this study, we developed a rapid and reproducible method for generating such a model in rats by weekly administration of diethylnitrosamine (DEN) at doses based on body weight (BW). By adjusting the duration of administration of DEN, the animals could be induced to develop HCC alone, or HCC and liver cirrhosis simultaneously. The latter model was used for evaluating the therapeutic effects of adenoviral delivery of interferon-alpha (IFN-alpha). Our results demonstrated that targeting of IFN-alpha expression to the liver significantly reduced liver tumor volume and ameliorated liver cirrhosis. Mechanistic studies revealed that IFN-alpha gene therapy induced immunomodulatory, antiproliferative, and proapoptotic activities that were effective in the control of tumor growth, and reduced the expressions of transforming growth factor-beta (TGF-beta) and tissue inhibitor of metalloproteinase-1 (TIMP-1), leading to amelioration of liver cirrhosis. These results suggest that IFN-alpha gene therapy is a promising strategy to treat HCC patients who have concomitant liver cirrhosis.

AAV vectors transduce hepatocytes in vivo as efficiently in cirrhotic as in healthy rat livers

“…Several authors have shown that these therapeutic effects can be achieved by inducing the expression of specific genes, such as interferon, bone morphogenetic proteins, superoxide dismutase, SPARC, HNF4a, methaloproteinases, urokinase plasminogen activator or insulin-like growth factor I among others, within the liver. [2][3][4][5][6][7][8][9][10] In most cases, the liver expression of the therapeutic transgene is obtained by using adenoviral vectors, which have a natural tropism for the liver. However, adenoviral vectors do not transduce cirrhotic livers as efficiently as healthy livers.…”

Sonoporation-mediated anti-angiogenic gene transfer into muscle effectively regresses distant orthotopic tumors

“…On day 14 after treatment, tumor volumes were measured as described previously. 30 In panels a and c, the numbers above the bars indicate the percentages of the average tumor volumes relative to those of the PBS control (n ¼ 6 for each group). For statistical difference in tumor volumes, *Po0.05; ***Po0.001, Mann-Whitney U-test, as compared between the indicated groups.…”

“…The primary multifocal liver tumor model was established in rats by feeding the animals with diethylnitrosamine following a previously described protocol. 30 The tumor model is harder to treat than the implanted model, so the animals were treated by US four times at 3-day intervals and killed on day 14 so tumor volumes could be measured following a previously described method. 30 For the combined chemotherapy and US treatment experiments, animals received US therapy on days 14, 21, 28 and 35 after tumor inoculation.…”

“…30 The tumor model is harder to treat than the implanted model, so the animals were treated by US four times at 3-day intervals and killed on day 14 so tumor volumes could be measured following a previously described method. 30 For the combined chemotherapy and US treatment experiments, animals received US therapy on days 14, 21, 28 and 35 after tumor inoculation. Doxorubicin (DOX) (2.5 mg kg À1 ) was administered intraperitoneally on days 15 and 29.…”

“…30 The sections were stained with a rat anti-mouse CD4, CD8 or CD31 monoclonal antibody (all at 1:50 dilution; BD Biosciences Pharmingen, Franklin Lakes, CA). Apoptotic cells were detected by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) assay using an in situ detection kit (Roche, Mannheim, Germany) following the manufacturer's instructions.…”