Table 2:
Models of inflammation and/or fibrosis induction: chemotoxic, dietary, and others.
| Model (References) | Details | Obesity, IR | Inflammation, Steatosis, Fibrosis, Cirrhosis | HCC development |
|---|---|---|---|---|
| Carcinogen-based HCC induction | ||||
| DEN (18, 85, 86) |
Genotoxic agent (DNA alkylation, oxidative stress). Single dose given at ~2 wks of age IP, does not require additional insult to develop HCC. Older mice need additional insult for HCC development, or long-term administration (dose and schedule can vary). |
No | No | Single Dose: Tumors 8–10 mo, 80–100% penetrance in males, 10–30% in females. Long term: Tumors at 7 months, ~60% penetrance (higher in males); metastasizes |
| Ccl4 (18, 41, 85, 87) |
Metabolite Ccl3 causes hepatocyte necrosis leading to fibrosis. Repetitive IP injection or oral gavage; varying degrees of fibrosis and cirrhosis depending on strain and dosing schedule. Often combined with DEN to accelerate tumorigenesis. |
No | Inflammation and steatosis; fibrosis in ~12 wks (self-resolving if Ccl4 discontinued) | 1–2 years for most strains. 50–94% penetrance (dose dependent), metastasizes |
| TAA (41, 85) |
Causes oxidative stress in hepatocytes. IP injection or administration in drinking water (orally less systemic toxicity). | No | Fibrosis progressing to cirrhosis in ~6 wks | Develop HCC in 6–12 mo |
| Aflatoxin B1 (86, 87) |
Metabolite causes DNA damage. IP injection in infant mice. |
No | Mild fibrosis | Early HCC in ~12 mo, high grade HCC in ~22–30 mo. Penetrance varies with strain (25–90%). Metastasizes |
| Diet-based HCC induction | ||||
| Choline deficient (CD) (85, 87) |
Oxidative damage and ER stress from defective phospholipid synthesis. Hepatic steatosis model with progression to HCC. | No | Steatohepatitis | HCC in 1–2 years, ~50% prevalence |
| CD + ethionine (CDE) (85) |
CD diet + supplementation with ethionine- a cytotoxic methionine analogue which causes inflammation and HSC activation. Accelerates tumor formation in CD model. | No | Inflammation and fibrosis | HCC by ~7 mo, 75% penetrance by 14 mo |
| Methionine choline deficient (MCDD) (18, 85, 88) |
High sucrose diet (40% sucrose, 10% fat) deficient in methionine and choline. Leads to buildup of cholesterol and fatty acid in liver. Model of NASH. High morbidity with significant weight loss. Inter-strain differences seen in immune infiltration. | No | Steatohepatitis in 1–2 wks, fibrosis in 8–10 wks | Not well studied in mice, due to long latency and toxic effects of diet |
| CD, L-amino acid defined (18, 88, 89) | CD diet with proteins replaced by semi-synthetic L-amino acids. Longer latency to pathology than MCDD. | No | Steatohepatitis and fibrosis | ~20% prevalence of HCC at 84 wks |
| High fat diet (HFD) (18, 85, 88) |
Ad libitum diet with 45% to75% fat; classic ratio 71% fat, 11% carbohydrates, 18% protein. Reproducible model of hepatic steatosis. | Yes | Fibrosis ~9 wks, Steatohepatitis ~19 wks | Usually does not progress to HCC without additional accelerating factor |
| Western / Fast food (18, 85) |
High cholesterol, high saturated fat, and high fructose. Similar phenotype to HFD + fibrosis. Histologically and transcriptomically very similar to human NASH and HCC. | Yes | Fibrosis in ~8 wks; NASH with progressive fibrosis after 6 months of diet | ~90% penetrance at 1 year |
| ALIOS (85) |
Diet high in trans-fats and high-fructose corn syrup, with removal of cage racks to promote sedentary behavior. Induction of HCC with only diet and lack of exercise. | Yes | At 16 wks, severe hepatic steatosis and inflammation. Fibrosis after 12-months | ~1 year, 60% penetrance |
| Ethanol (18) |
Lieber-DeCarli diet: ad libitum liquid diet with ethanol as 36% of calories. NIAAA model: 10 day Lieber-DeCarli diet + single binge feed of alcohol. Tsukamoto-Franch model: Infusion pump placed in stomach for continuous ethanol feeds. Do not induce HCC, but rather create a background of alcohol-induced liver disease. |
No | LD: Mild steatosis, very mild inflammation NIAAA: binge synergistically causes liver injury, inflammation, fatty liver TF: Severe steatosis, mild inflammation and fibrosis |
No; requires additional insult |
| Other models of inflammation or fibrosis | ||||
| MUP-uPA +HFD (18, 85) |
Major urinary protein (MUP)-urokinase type plasminogen activator (uPA) transgenic mice. uPA overexpression in hepatocytes causes ER stress and TNF-dependent inflammation. Model of inflammation-induced HCC. |
Yes | Steatosis from HFD, plus immune cell infiltration leading to HCC, fibrosis at ~24 wks after HFD initiation | HCC at ~ 32–40 wks, penetrance ~80% |
| Mdr2−/− (18, 20, 86) |
MDR2 knockout mice lack a phospholipid floppase responsible for biliary excretion of phospholipids; leads to buildup of bile salts, inflammation due to bile acid mediated cholestatic damage to hepatocytes. Chronic liver inflammation and fibrosis model. | No | Cholestatic hepatitis by ~3wks, fibrosis by ~8–10 wks (females>males) | Dysplastic lesions at 4–6 mo, tumors at ~1 year, ~100% penetrance. Pulmonary metastasis at ~1.5 years |
| Fah−/− (18) |
Lack fumarylacetoacetate hydrase; hepatic fumarylacetoacetate buildup causes inflammation, fibrosis, and liver dysfunction that can be controlled with NTBC. Used to model cyclic liver inflammation and injury via repeated withdrawal of NTBC. |
No | Hepatic inflammation and fibrosis | HCC in ~30% after 2 cycles of NTBC withdrawal and re-initiation; ~100% penetrance after 6 cycles |
| Liver-specific PTEN −/− (18, 85, 86) |
Albumin-Cre transgenic mice with floxed PTEN allele; model of obesity-related HCC. | No | Hepatomegaly and steatosis at ~10 wks, Inflammation and fibrosis at ~40 wks | ~1.5 years; ~80% penetrance in males, 50% in females |
| Liver specific Tak1 −/−(86) | Albumin-Cre or ALFP-Cre transgenic mice crossed with TGF-β Activated Kinase 1 conditional allele leads to hepatocyte death and resultant inflammation and fibrosis. Model of chronic hepatocyte injury. |
No | hepatic inflammation and fibrosis by 1 month | Tumors develop ~4 mo; penetrance ~80 % by 9–10 mo |
| Ob/ob and db/db (18) |
Ob/ob: no functional leptin; Db/db: mutated leptin receptor. Effectively remove leptin signaling leading to hyperphagia, obesity, hyperglycemia and insulin resistance, hyperlipidemia, fatty liver Model of metabolic syndrome. |
Yes | No spontaneous fibrosis or steatohepatitis without addition of diet (ie, HFD or MCDD). Leptin is required for fibrosis, so only db/db can develop | No; requires additional insult |
IR = Insulin resistance ; DEN = Diethylnitrosamine; IP= intraperitoneal; Ccl4 = carbon tetrachloride; wks = weeks; mo= months; TAA = Thioacetamide; ALIOS: American Lifestyle-Induced Obesity Syndrome; TNF = tumor necrosis factor; MDR2 = Multidrug resistance 2; Fah = Fumarylacetoacetate hydrase; NTBC = (2-[2-nitro-4-(trifluoromethyl) benzoyl]cyclohexane-1,3-dione or nitisinone); PTEN = Phosphatase and tensin homolog; Tak1 = TGF-β Activated Kinase