Development of an orthotopic model of invasive pancreatic cancer in an immunocompetent murine host.
OBJECTIVE
The most common preclinical models of pancreatic adenocarcinoma utilize human cells or tissues that are xenografted into immunodeficient hosts. Several immunocompetent, genetically engineered mouse models of pancreatic cancer exist; however, tumor latency and disease progression in these models are highly variable. We sought to develop an immunocompetent, orthotopic mouse model of pancreatic cancer with rapid and predictable growth kinetics.


METHODS
Cell lines with epithelial morphology were derived from liver metastases obtained from Kras(G12D/+);LSL-Trp53(R172H/+);Pdx-1-Cre mice. Tumor cells were implanted in the pancreas of immunocompetent, histocompatible B6/129 mice, and the mice were monitored for disease progression. Relevant tissues were harvested for histologic, genomic, and immunophenotypic analysis.


RESULTS
All mice developed pancreatic tumors by two weeks. Invasive disease and liver metastases were noted by six to eight weeks. Histologic examination of tumors showed cytokeratin-19-positive adenocarcinoma with regions of desmoplasia. Genomic analysis revealed broad chromosomal changes along with focal gains and losses. Pancreatic tumors were infiltrated with dendritic cells, myeloid-derived suppressor cells, macrophages, and T lymphocytes. Survival was decreased in RAG(-/-) mice, which are deficient in T cells, suggesting that an adaptive immune response alters the course of disease in wild-type mice.


CONCLUSIONS
We have developed a rapid, predictable orthotopic model of pancreatic adenocarcinoma in immunocompetent mice that mimics human pancreatic cancer with regard to genetic mutations, histologic appearance, and pattern of disease progression. This model highlights both the complexity and relevance of the immune response to invasive pancreatic cancer and may be useful for the preclinical evaluation of new therapeutic agents.
Tseng
William W
WW
Department of Pathology, Stanford University, Palo Alto, California, USA.
Winer
Daniel
D
Kenkel
Justin A
JA
Choi
Okmi
O
Shain
Alan H
AH
Pollack
Jonathan R
JR
French
Randy
R
Lowy
Andrew M
AM
Engleman
Edgar G
EG
D000230:Adenocarcinoma / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D004195:Disease Models, Animal; D018450:Disease Progression; D005260:Female; D007121:Immunocompetence; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009361:Neoplasm Invasiveness; D010190:Pancreatic Neoplasms / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D014407:Tumor Cells, Cultured