Preneoplastic Pancreatic (PanIN) Organoids as an in vitro Model of Pancreatic Cancer Progression
Lead Research Organisation:
University of Liverpool
Department Name: Institute of Translational Medicine
Abstract
Pancreatic Ductal Adenocarcinoma (PDAC) has among the worst outcome of all human malignancies. Most patients die of pancreatic cancer within one year of diagnosis, and this poor prognosis is due to strong resistance to conventional chemotherapy. Therefore, there is an urgent and unmet need for developing biologically relevant approaches to understand the molecular mechanisms driving the progression from a non-lethal premalignant stage (called Pancreatic Intraepithelial Neoplasia (PanIN)) to invasive and lethal PDAC, and to use this knowledge to identify novel options for treatment.
Unfortunately, it is not possible to culture cells from human premalignant pancreatic PanIN lesions, which has precluded a comprehensive investigation of the molecular basis of the progression from PanIN lesions to PDAC. To overcome this limitation, researchers have employed mouse models of pancreatic cancer that recapitulate the essential features of human PanIN lesions to study the molecular mechanisms that drive the malignant transformation of the PanIN cell to give rise to the tumourigenic PDAC cell. However, in vivo approaches are costly, time-consuming and raise ethical concerns. Therefore, in vitro alternatives to investigate pancreatic cancer progression are urgently needed.
Pancreatic organoids are self-organised three-dimensional structures of pancreatic cells that can be cultured in a matrix of proteins and a defined cocktail of growth factors. Pancreatic organoids recapitulate critical aspects of the pancreatic cancer biology and, crucially, they can be genetically and pharmacologically manipulated, allowing the targeted evaluation of selected genes. Pancreatic organoids derived from advanced pancreatic cancer tissue have shown to be a biologically relevant system to study the mechanisms of tumour maintenance, reducing the use of animals. However, the use of organoids established from pancreatic premalignant (PanIN) lesions to study pancreatic cancer progression is still largely unexplored.
In this proposal, we propose to validate the use of pancreatic organoids derived from murine pancreatic premalignant (PanIN) tissue to study the molecular mechanisms driving the progression from preinvasive lesion to invasive pancreatic cancer. Experimental data obtained in a mouse model of PanIN-to-PDAC progression will be validated in PanIN organoids by downregulating the expression of genes found to be recurrently inactivated in the in vivo model. Next, the relevance of PanIN organoids to perform therapeutic studies will be evaluated by assessing their capacity to predict response to Gemcitabine, an anti-cancer chemotherapy drug that is the standard of care for pancreatic cancer. Finally, the clinical relevance of the PanIN organoid platform will be assessed by validating our findings in resected human pancreatic cancer specimens.
Overall, we anticipate that our approach will offer a biologically relevant in vitro model to understand how pancreatic cancer progresses, thereby reducing and ultimately replacing the use of mice to study vital biological aspects of this disease.
Unfortunately, it is not possible to culture cells from human premalignant pancreatic PanIN lesions, which has precluded a comprehensive investigation of the molecular basis of the progression from PanIN lesions to PDAC. To overcome this limitation, researchers have employed mouse models of pancreatic cancer that recapitulate the essential features of human PanIN lesions to study the molecular mechanisms that drive the malignant transformation of the PanIN cell to give rise to the tumourigenic PDAC cell. However, in vivo approaches are costly, time-consuming and raise ethical concerns. Therefore, in vitro alternatives to investigate pancreatic cancer progression are urgently needed.
Pancreatic organoids are self-organised three-dimensional structures of pancreatic cells that can be cultured in a matrix of proteins and a defined cocktail of growth factors. Pancreatic organoids recapitulate critical aspects of the pancreatic cancer biology and, crucially, they can be genetically and pharmacologically manipulated, allowing the targeted evaluation of selected genes. Pancreatic organoids derived from advanced pancreatic cancer tissue have shown to be a biologically relevant system to study the mechanisms of tumour maintenance, reducing the use of animals. However, the use of organoids established from pancreatic premalignant (PanIN) lesions to study pancreatic cancer progression is still largely unexplored.
In this proposal, we propose to validate the use of pancreatic organoids derived from murine pancreatic premalignant (PanIN) tissue to study the molecular mechanisms driving the progression from preinvasive lesion to invasive pancreatic cancer. Experimental data obtained in a mouse model of PanIN-to-PDAC progression will be validated in PanIN organoids by downregulating the expression of genes found to be recurrently inactivated in the in vivo model. Next, the relevance of PanIN organoids to perform therapeutic studies will be evaluated by assessing their capacity to predict response to Gemcitabine, an anti-cancer chemotherapy drug that is the standard of care for pancreatic cancer. Finally, the clinical relevance of the PanIN organoid platform will be assessed by validating our findings in resected human pancreatic cancer specimens.
Overall, we anticipate that our approach will offer a biologically relevant in vitro model to understand how pancreatic cancer progresses, thereby reducing and ultimately replacing the use of mice to study vital biological aspects of this disease.
Technical Summary
Despite advances in our understanding of the molecular pathogenesis of pancreatic ductal adenocarcinoma (PDAC), the overall survival has remained unchanged over recent decades (~6%). There is an urgent and unmet need for understanding the molecular mechanisms driving the progression from a non-lethal preneoplastic stage (Pancreatic Intraepithelial Neoplasia, PanIN) to invasive and lethal PDAC, and to use this knowledge to identify novel options for PDAC therapy. Mouse models of pancreatic cancer have enabled a comprehensive investigation of the genetics and biology of this disease. However, in vivo approaches are costly and time-consuming, and crucially raise ethical concerns. To overcome these limitations, organoids derived from PDAC tissue have been established as a biologically relevant system to study advanced stages of pancreatic cancer, reducing the use of animals. However, the use of organoids derived from pancreatic preinvasive (PanIN) lesions to study the molecular basis of PanIN-to-PDAC progression is still largely unexplored. We have proved that PanIN organoids undergo neoplastic transformation after inactivating Trp53, a key tumour suppressor gene inactivated during PanIN-to-PDAC progression, validating this model to study the biology of pancreatic cancer progression, drastically reducing the number of mice required to perform experiments and ultimately replacing their use. Our scientific goal is to validate the use of PanIN organoids to study pancreatic cancer progression. Experimental data obtained in an in vivo transposon-mediated insertional mutagenesis screen will be validated in PanIN organoids by downregulating tumour suppressor gene candidates found recurrently inactivated in our in vivo screen. Then, we will assess the relevance of PanIN organoids to perform therapeutic studies and predict response to gemcitabine. Finally, we will confirm the clinical significance of PanIN organoids by validating our findings in resected human PDAC specimens.