Table 3 In vitro and in vivo models of cholangiocarcinoma
From: Cholangiocarcinoma 2020: the next horizon in mechanisms and management
Models | Main features | Advantages | Limitations | Examples | Refs |
---|---|---|---|---|---|
In vitro models | |||||
Cell lines | A permanently established cell culture that proliferates indefinitely given appropriate fresh medium and space | Devoid of non-neoplastic and necrotic tissues; growth can be synchronized; high number of cells generated; easy assessment of proliferation and cell death; possibility of genetic manipulation (overexpression, silencing) and drug administration | Become different from original tumours following in vitro passages; generally representing only advanced tumour; lack of TME (immune cells, stromal cells and blood vessels); genetically unstable; normal cholangiocyte cultures should be used as control | Human (HuCC-T1 KKU-156, Mz-ChA-1, TFK-1, QBC939, etc.); mouse (SB1-SB7); rat (CGCCA) CCA cell lines | |
Primary cultures | Cell culture system that is formed by culture cells directly obtained from CCA tissues | More similar than cell lines to the in vivo situation | Labour-intensive; only generated from surgically resected specimens; lack of realistic cell–cell and cell–matrix interactions | Primary cultures obtained from human or rodent (mice and rats) resected CCA specimens | |
Spheroids | Cell aggregates that are either grown in suspension or embedded in a 3D matrix using 3D culture methods | Mimic spatial architecture, physiological responses, secretion of soluble mediators, gene expression patterns and drug resistance mechanisms of CCA | Long-term culture difficult | Human CCA spheroids in 3D culture; 3D rat CAF–CCA cell co-culture models | |
Organoids | Simplified and ‘miniaturized’ version of an organ generated in vitro in 3D and preserving the tissue of origin | Accurately mimic genetics, cell organization and behaviour, and response to drugs or mutations, in a setting that resembles the original microenvironment; allow the study of the various phases of carcinogenesis; can be grown from a limited amount of starting material (biopsy samples); useful for gene editing | Lack of circulation limits their size and complexity; accuracy of the various phases of cancer development still need to be fully validated in these 3D structures | Organoids of CCA isolated from human or rodent (mice and rats) liver specimens | |
In vivo models | |||||
Chemically- and infestation-induced models | Mice, rats or Syrian hamsters subjected to the administration of chemical carcinogens via various sites and modalities | Enable the identification of natural or occupational carcinogens; tumour onset and progression easy to assess from early stages; presence of chronic inflammation; ‘natural’ microenvironment and intact immune system | Different pharmacokinetics and drug metabolism from humans; potential drug toxicity; difficult to identify the driving pathogenetic events; development of cholangiofibrosis and intestinal metaplasia preceding CCA occurrence in TAA and Furan models; monitoring of carcinogenesis using the same instrumentation as in humans (CT scan, MRI) | TAA Furan Tp53ko–CCl4; diethylnitrosamine; dimethylnitrosamine; Opisthorchis viverrini | |
Genetically-engineered mouse models (GEMM) | Mice whose genome has been altered using genetic engineering techniques | Tumour onset and progression easy to assess from early stages; possible to engineer specific mutations to study gene function or to add reporters; well-established technology; amenable to genetic screening approaches; tumours develop in the presence of an intact immune system and a proper tumour microenvironment; able to predict the response of human tumours to therapy | Mouse strains do not represent the genetic diversity of the human population; mouse tumours grow very fast relative to human tumours; the engineering strategies are complicated and expensive, requiring a dedicated infrastructure; lack of chronic inflammation in the background; monitoring of carcinogenesis using the same instrumentation as in humans (CT scan, MRI) | Alb‐Cre;Smad4f/f;Ptenf/f Alb‐Cre;KrasLSLG12D/+;Ptenf/f Alb‐Cre;KrasLSLG12D/+;Tp53f/f Alb‐Cre;KrasLSL‐G12D/+;Fbxw7LSL‐ R468C Alb‐Cre;Idh2LSL‐R172;KrasLSL‐ G12D Alb‐Cre;NotchIC Alb‐Cre;Tp53f/f;NotchICD | |
Implantation models | Mice or rats in which the tumour component from an external source (cell lines, human tissues, etc.) is implanted either in the analogous (orthotopic) or a different (ectopic) organ from the original | Easy to generate and inexpensive; recapitulate some of the human tumour features | Useful mainly for the study of advanced tumour stages; mainly stable at the genetic level; different tumour microenvironment from the native condition and lack of immune cells | Subcutaneous xenografts of human (Mz-ChA-1, QBC939, etc.) or mouse (SB1-SB7) cell lines in nude or syngeneic mice; patient-derived xenografts in female NOD/SCID mice; bile duct inoculation of tumorigenic rat cholangiocyte cell lines | |
Transposon-based models | Mice in which a gene or a combination of genes is stably integrated into the hepatocytes integrated using a transposase | Tumour onset and progression easy to assess from early stages; possible to deliver specific mutations to study gene function or to add reporters; easy, inexpensive, fast, and high-reproducible technology; amenable to genetic screening approaches; tumours develop in the presence of an intact immune system and a proper tumour microenvironment; allow prediction of the response of human tumours to therapy | Mouse tumours grow very fast relative to human tumours; CCA develop from mature hepatocytes and not from cholangiocytes or progenitor or stem cells; monitoring of carcinogenesis using the same instrumentation as in humans (CT scan, MRI) | NRASV12;Ink4A;Arf−/− PIK3CA;Yap NICD1 NICD1;myrAKT YAPS127A;myrAKT NRASV12;myrAKT NICD1;KRASLSLG12D+ JAG1;myrAKT YAPS127A;myrAKT + IL-33 injection |