Abstract:
Pancreatic ductal adenocarcinoma (PDAC) is currently the third leading cause of cancer-related mortality in the United States and is projected to become the second by 2030. Despite advances in oncology, PDAC remains notoriously difficult to treat, with a dismal five-year survival rate of only 12.8%. This poor prognosis is largely attributed to late-stage diagnosis, intrinsic drug resistance, and the unique composition of its tumor microenvironment (TME), which presents significant barriers to therapeutic efficacy. Among the most prominent components of the TME are cancer-associated fibroblasts (CAFs), which not only constitute a large portion of the tumor stroma but also actively modulate tumor progression and treatment response. CAFs are functionally diverse and can either promote or suppress tumor growth depending on their phenotypic subtype. They are commonly categorized into two major subtypes: myofibroblastic CAFs (myCAFs), which exhibit tumor-suppressive characteristics and are marked by alpha-smooth muscle actin (α-SMA) expression; and inflammatory CAFs (iCAFs), which secrete pro-tumorigenic cytokines such as interleukin-6 (IL-6). The dynamic plasticity between these subtypes presents an opportunity to therapeutically reprogram CAFs to enhance treatment outcomes. However, the lack of tools to systematically study and quantify CAF subtype transitions has limited progress in this area. In this project, we aim to develop a novel reporter-based assay that allows for the real-time visualization and functional assessment of CAF subtype modulation in vitro. By engineering a dual-reporter cell line that expresses fluorescent markers under the control of the α-SMA and IL-6 promoters, we can simultaneously track the transition between myCAF and iCAF phenotypes using fluorescence microscopy. This system enables us to screen a variety of therapeutic compounds—individually and in combination—across different doses and time intervals to evaluate their impact on CAF fate. The broader goal of this research is to identify drug candidates that can shift CAF populations toward a more tumor-restraining state, thereby improving the efficacy of cancer therapies. By gaining a deeper understanding of how therapeutics affect CAF heterogeneity, we hope to inform preclinical drug development and support the rational design of combination strategies that target both cancer cells and their supportive stromal environment. Ultimately, this work contributes to the ongoing effort to overcome treatment resistance in pancreatic cancer by addressing its complex microenvironmental landscape.
