Models of intrahepatic cholangiocarcinoma: novel tools and therapeutic applications

Figures & data

Box 1 Considerations for the development and utilization of iCCA models

Genetics:	Are specific genetic alterations relevant to the scientific question?
Biologic context:	Is an in vivo environment necessary? Should the host be immune competent? Is it important to model the pathologic progression of the disease?
Pathogenic context:	Is the pathogenic setting in which the tumor developed (eg, liver fluke infection, fibrosis) relevant?
Cell of origin:	What cell compartment, hepatocytes and/or biliary epithelial cells (BECs), should be targeted (eg, when targeting mutations using Cre-Lox technology)?
Practicality:	Considering that the available modeling systems widely vary in the resources they require (ie, cost and time), how does one optimally utilize the different systems to address the scientific question?

Abbreviation: iCCA, intrahepatic cholangiocarcinoma.

Table 1 Summary of injury and carcinogen models

Agent	Characteristics	Mutations	Animal	Reference
TAA	Carcinogen, fibrosis	Krt19-Cre^ERT; Rosa26^LSL-YFP; Tp53^f/,f	Mouse	17, 48, 49
		Alb-Cre^ERT; Rosa26^LSL-LacZ	Mouse	16
		WT	Rat	5, 49
DEN/DMN	Carcinogen, fibrosis	Alb-Cre^ERT; Hnf4a^f/f	Mouse	20
		Phd2^+^−	Mouse	4
		WT with BDL	Mouse	6
		WT with O. viverrini infection	Hamster	8–12, 18
		WT with C. sinensis infection	Hamster	13
CCL 4	Fibrosis	Tp53−^/− and Tp53^+/^−	Mouse	19
DDC	Cholestatic injury, ductular reaction, biliary fibrosis	Proml-Cre^ERT; Tgfbr2^f^/f;Pten^f/f	Mouse	14
		Proml-Cre^ERT; Kras^LSL-Gl^Citation2^D; Tp53^f/f and Tp53^+/+	Mouse	22
		Proml-Cre^ERT; Pten^f/f; Tp53^f/^f	Mouse	22
		Proml-Cre^ERT; Pten^f/f; Cdkn2a^f/f	Mouse	22
BDL	Cholestatic injury, ductular reaction, biliary fibrosis	WT with DEN	Mouse	7
		SB-mediated AKT and YAP overexpression	Mouse	15, 59, 61

Abbreviations: BDL, bile duct ligation; CCI₄, carbon tetrachloride; C. sinensis, Clonorchis sinensis; DDC, 3,5-diethoxycarbonyl-1,4-dihydrocollidine; DEN, diethylnitrosamine; DMN, dimethylnitrosamine; O. viverrini, Opisthorchis viverrini; SB, sleeping beauty; TAA, thioacetamide; WT, wild type.

Table 2 Summary of iCCA Cre-Lox GEMMs

Cre driver	Mutations	Tumor spectrum	Key finding	Reference
Cre activity: hepatoblasts
Alb-Cre	Kras^LSL-G12D; Tp53^f/f and Tp53^f/+	Mostly iCCA, some mixed, rare HCC in Tp53^f/f	Tumors have high levels of basal autophagy	47
	Kras^LSL-G12D; IDH2^R172K	Exclusive iCCA	IDH2 mutation promotes biliary differentiation	20
	Kras^LSL-G12D; Cdh^f/f	Mostly HCC, some mixed, some iCCA	Cdhl suppresses EMT and liver tumorigenesis	4
	KrasLSL-G12D; Pten^f/f and Pten^f/+ Pten^f/f	Exclusive iCCA in Pten^f/f	Pten status may determine tumor spectrum	41
		Mostly mixed, some iCCA	miR-21 is important for tumor development and growth	24, 25
	Pten^f/f; Tgfbr2^f/f	Mixed and iCCA	Tgfbr2 deletion shifts tumor phenotype from HCC to iCCA	14, 26
	Pten^f/f; Smad4^f/f	Exclusive iCCA	Deletion of Pten and Smad4 cooperate to induce iCCA	27
	Pten^f/f; Grp78^f/f	HCC, mixed, iCCA – proportions unclear	Grp78 mediates liver cancer progression induced by Pten loss	28
	Pten^f/f; Grp94^f/f	HCC, mixed, iCCA – proportions unclear	Double KO has accelerated tumorigenesis and ERK activation	29
	Rosa26^LSL-NICD	Exclusive iCCA	Notch activation can drive iCCA	30
	Rosa26^LSL-NICD; Tp53^f/f	Exclusive iCCA	Notch activation and Tp53 deletion cooperate to induce iCCA	32
	Mobla^f/f; Moblb^-/-	Mostly mixed, some iCCA, some HCC	Inactivation of Hippo signaling can promote iCCA	31
	Tp53^f/f	HCC, mixed, iCCA – proportions unclear	Deletion of Tgfbr2 decreases tumor formation and growth	33
Alfp-Cre	Tp53^f/f	HCC, mixed, iCCA – proportions unclear	Tumors with Tp53 deleted express stem cell marker Nestin	46
Cre activity: hepatocytes
Alb-Cre^ERT2	Rosa26^LSL-LacZ or Rosa26^LSI-YFP + TAA	Exclusive iCCA	Mutated hepatocytes can give rise to iCCA	16, 34
	Hnf4a^f/f + DEN/DMN	Exclusive iCCA	Hnf4a suppresses iCCA development	20
	Kras^LSL-G12D; Pten^f/f	iCCA with early Tam; HCC with late Tam	Tumors arise from BECs with early Tam administration	41
AAV8-TBG-Cre	Pten^f/f; Tgfbr2^f/f	Mostly iCCA, rarely mixed, and HCC	Mutated hepatocytes can give rise to iCCA	14
Cre activity: BECs
Krt19-Cre^ERT	Rosa26^LSL-YFP; Tp53^f/f + TAA	Exclusive iCCA	BEC-specific Tp53 deletion can promote iCCA	17, 48, 49
	Kras^LSL-G12D; Pten^f/f	Exclusive iCCA	Kras and Pten mutations in BECs give rise to iCCA	41
	Pten^f/f; Tgfbr2^f/f + DDC	Exclusive iCCA	Mice develop iCCA	14
Ah-Cre^ERT	Pten^f/f; Kras^LSL-V12D	Exclusive iCCA	Pten and Kras cooperate to form iCCA	35
Proml-Cre^ERT2	Pten^f/f; Tgfbr2^f/f + DDC	Exclusive iCCA	Mice develop iCCA	14
	Pten^f/f; Tp53^f/f + DDC	HCC, mixed, iCCA – proportions unclear	Liver injury increases liver cancer risk	22
	Pten^f/f; Cdkn2a^f^/f + DDC	HCC, mixed, iCCA – proportions unclear	Liver injury increases liver cancer risk	22
	Kras^LSL-G12D; Tp53^f/f and Tp53^+/+ + DDC	HCC, mixed, iCCA – proportions unclear	Liver injury increases liver cancer risk	22

Abbreviations: AAV8, Adeno-associated virus 8; BECs, biliary epithelial cells; DDC, 3,5-diethoxycarbonyl-1,4-dihydrocollidine; EMT, epithelial-mesenchymal transition; GEMMs, genetically engineered mouse models; HCC, hepatocellular carcinoma; iCCA, intrahepatic cholangiocarcinoma; NICD; Notch1 intracellular domain; Tam, tamoxifen.

Figure 1 Schematic of Cre driver activity within the liver.

Note: *Specificity depends on when tamoxifen is administered.
Abbreviation: BEC, biliary epithelial cell.

Figure 2 Current model of the cells of origin in primary liver cancers.

Abbreviations: BEC, biliary epithelial cell; HCC, hepatocellular carcinoma; iCCA, intrahepatic cholangiocarcinoma.

Table 3 Summary of iCCA SB models

Model	Tumor spectrum	Key finding	Reference
AKT; NRAS	Mostly HCC, some mixed, some iCCA	Coactivation of Akt and Ras signaling induces liver tumors	56
		Notch signaling is critical for liver tumor development	57
		Bmil is critical for liver tumor development	58
AKT; NICD	Exclusive iCCA	iCCA can originate from AKT/NICD-mutant hepatocytes	43
AKT; JagI	Exclusive iCCA	AKT/JagI cooperate to form iCCA	55
Akt; YAP + IL-33 and BDL	Exclusive iCCA	IL-6 promotes tumorigenesis	15, 59
		Treatment with FGFR inhibitor reduces tumor burden	61
YapI; PIK3CA	Mostly HCC and mixed, some iCCA	YapI/PIK3CA cooperate to induce liver tumors	60
YAP; shTp53	Mixed – undifferentiated tumors	Nestin is required for tumorigenesis	46
YAP; shTp53 + shAPC or NICD	iCCA if NICD, HCC if shAPC	Tumor differentiation could be directed	46
NICD; IDHI; shTp53	Exclusive iCCA	All three cooperate to induce iCCA	54

Abbreviations: BDL, bile duct ligation; HCC, hepatocellular carcinoma; iCCA, intrahepatic cholangiocarcinoma; IDH1, IDH1R132C; NICD, Notchl intracellular domain; PIK3CA, PIK3CAH1047R; YAP, YAPS127A; SB, sleeping beauty.

Liu Y, Meyer C, Xu C, et al. Animal models of chronic liver diseases. Am J Physiol Gastrointest Liver Physiol. 2013;304(5):G449–G468.

 Web of Science ®Google Scholar