Development of a spatially defined 3D<i>in vitro</i>coculture construct modeling pancreatic cancer-associated cachexia.

Abstract

Pancreatic cancer-associated cachexia is marked by adipose tissue wasting, thermogenic remodeling, and a state of hypermetabolism, yet robust preclinical models to study these phenomena are lacking. In this study, we present a spatially defined three-dimensional (3D) core-shell microcuboid coculture platform designed to investigate the interaction between adipocytes and pancreatic cancers. This innovative system consists of differentiated white adipocytes at the core, surrounded by pancreatic ductal adenocarcinoma (PDAC) cells embedded in 3D-printed microcuboids, arranged concentrically within a collagen coculture matrix construct. Within this framework, we observed significant enhancement of adipocyte lipolysis and browning, as evidenced by BODIPY dye-tracked lipid migration, sustained glycerol release, and progressive expression of extracellular UCP1 or the mitochondrial brown fat uncoupling protein 1, particularly pronounced in cocultures involving aggressive pancreatic cancer cell lines. The integrity of the core-shell architecture persisted for up to 21 d but progressively disintegrated under the influence of the cancer cells marked by cancer cell invasion into the adipocyte regions. Gene profiling revealed a downregulation of adipogenic markers, such as<i>Pparg, Plin1</i>, and<i>Lipe</i>, alongside an increase in<i>Ucp1</i>transcripts, suggesting a metabolic shift from lipid storage to utilization and thermogenic activation. In contrast to existing 3D engineered systems, our platform offers enhanced long-term viability, controlled compartmentalization, mechanical tunability, and high spatiotemporal resolution. It effectively recapitulates the dynamic interplay between cancer and adipose cells, along with the catabolic characteristics of PDAC-associated cachexia, serving as a scalable<i>in vitro</i>tool for mechanistic investigations, and for testing potential anti-cachexia interventions, filling the gap between simplistic<i>in vitro</i>assays and complex animal models.