The winner of the 2021 Cancer Research and Oncology Virtual Event Poster Competition was Meaghan Gleason, a senior at Duquesne University in Pittsburgh, PA. Gleason presented a poster titled, “Evaluating drug delivery methods and αPD-1 combination therapies in a murine model of colorectal cancer.”
Colorectal cancer is the third most diagnosed cancer in both males and females in the United States, accounting for about 8% of the cancer diagnoses for each gender. Additionally, 2021 estimates predict that colorectal cancer will be the third leading cause of cancer-related mortality in both males and females totaling over 50,000 deaths.
Cycoloxygenase-2 (COX-2) is an enzyme that is overexpressed in the tumor microenvironment. Higher levels of COX-2 expression is correlated with shorter survival times and colorectal cancer progression. Celecoxib, a COX-2 inhibitor, can block COX-2 signaling. In mouse models of colorectal cancer, celecoxib is associated with slowed tumor growth and longer survival.
A common way of administering drugs, including celecoxib, to laboratory mice is via intraperitoneal (IP) injection. Repeated injections cause stress to the animal receiving the injection and can have negative effects on the anti-tumor immune response. Thus, the stress caused by repeated injections could make data from pre-clinical experimental protocols difficult to interpret. Therefore, any method of drug delivery null of this external stressor could generate more reliable data, which could in turn better inform clinical studies.
Meaghan’s award-winning poster provided data comparing administration of celecoxib via intraperitoneal injection or orally through food. The food is specially manufactured so that the amount of food the mouse consumes daily contains the correct daily dose of celecoxib.
The data presented in the poster compared an immunotherapeutic regimen in combination with celecoxib. The data demonstrated that celecoxib delivered by intraperitoneal injection and through food had a similar effect; administration of celecoxib via food did not hinder the efficacy of the combination treatment regimen.
Meaghan explained, “The most meaningful part of my project was that these findings may contribute to future research by improving oral drug delivery methods for other medications. Similar pilot studies could be conducted with other drugs typically delivered by intraparitoneal injection. If similar efficacy is seen a switch to delivering the drug via food could increase the accuracy of murine experiments and could be shown to have relevence for clinical research and treatment as well."