Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease. Although surgery is the primary curative option, more than 75% of patients are ineligible and respond only transiently, to chemo- and radiotherapy (RT). New and effective treatment option is desperately needed. Recently, the development of RT as a therapeutic modulator for systemic treatment such as immunotherapy has cast the use of radiation into a pivotal role in the management of PDAC, inspiring several clinical trials. Given these early clinical studies, there is a compelling need to establish a clinically-relevant experimental system to further advance our understanding of the role of RT . A genetically engineered mouse model would provide a powerful model system to dissect the radiobiological mechanism of RT. The majority of PDAC (>90%) has somatic mutations in the KRAS signaling pathway. Importantly, using publicly available gene expression datasets, we found that TWIST1 is overexpressed in human PDAC which represents the most aggressive ?squamous variant? subset of pancreatic cancer. We hypothesize that the generation of a pancreas specific Kras-Twist1 autochthonous mouse model provides an innovative resource to determine how TWIST1 contributes to tumorigenesis and progression. As for the important pre-clinical research to study treatment response of the murine PDAC model, radiation needs to mimic RT used for human. Such advanced technology is now available in the form of the small animal radiation research platform (SARRP) pioneered at our group. The SARRP is equipped with on- board cone-beam CT (CBCT) to guide irradiation. Recognizing that CBCT imaging is inadequate for localizing the PDAC growing in a low image contrast tissue environment, we innovated bioluminescence tomography (BLT) on board the SARRP to complement CBCT guidance. As an important complement, we engineered inducible Twist1-Luc gene expression in our PDAC model such that the disease progression can be monitored by bioluminescence imaging and the spontaneous PDAC can also be localized with BLT for radiation delivery. In response to PAR-16-176, we propose to integrate the inducible Kras-Twist1-Luc PDAC model and the CBCT-BLT-guided SARRP to establish a novel experimental system that will enable researchers to evaluate and develop new treatment options for human squamous variant PDAC in ways that have not been feasible before. To achieve this goal, we propose to (1) develop an inducible Twist1 transgenic autochthonous PDAC model and determine if Twist1 overexpression can cooperate with KrasG12D to accelerate PDAC tumorigenesis; (2) advance the targeting and quantitative imaging capabilities of the BLT-guided SARRP system for the PDAC model. The success of this proposal will provide a model system with strong pre-clinical foundation to study the effectiveness of combining radiation and other therapeutic agents for PDAC in great translational opportunity.

Public Health Relevance

We propose to integrate a novel clinically-relevant pancreatic cancer mouse model with an advanced x- ray/optical tomography-guided small animal radiation research platform. This new experimental system will greatly enhance the progress of pre-clinical oncology research on the development of new treatment options for pancreatic cancer. This is particularly important at the present time when radiation is being tested not only for its efficacy for local control but also as an effective modulator for other systemic therapy. !

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Exploratory/Developmental Grants (R21)
Project #
1R21CA223403-01
Application #
9439198
Study Section
Special Emphasis Panel (ZCA1)
Program Officer
Obcemea, Ceferino H
Project Start
2018-06-15
Project End
2020-05-31
Budget Start
2018-06-15
Budget End
2019-05-31
Support Year
1
Fiscal Year
2018
Total Cost
Indirect Cost
Name
Johns Hopkins University
Department
Radiation-Diagnostic/Oncology
Type
Schools of Medicine
DUNS #
001910777
City
Baltimore
State
MD
Country
United States
Zip Code
21205
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Taparra, Kekoa; Wang, Hailun; Malek, Reem et al. (2018) O-GlcNAcylation is required for mutant KRAS-induced lung tumorigenesis. J Clin Invest 128:4924-4937
Vendetti, Frank P; Karukonda, Pooja; Clump, David A et al. (2018) ATR kinase inhibitor AZD6738 potentiates CD8+ T cell-dependent antitumor activity following radiation. J Clin Invest 128:3926-3940