P4HA1 Mediates Hypoxia-Induced Invasion in Human Pancreatic Cancer Organoids.

[UNLABELLED] Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with dismal prognosis. PDAC develops in a hypoxic environment in which cells adapt and activate processes to allow survival under low-oxygen conditions, some of which may enhance the ability of cancer cells to invade locally or metastasize distantly. Using human PDAC organoids, we determined that hypoxia consistently enhanced invasion across 11 patient-derived models. Using RNA sequencing of hypoxic invasive organoids (compared with matched invasive normoxic organoids from the same patients), we identified prolyl 4-hydroxylase subunit alpha 1 (P4HA1) as a potential regulator of PDAC invasion in hypoxia. Leveraging publicly available datasets from human tissue, we determined that P4HA1 is more highly expressed in PDAC compared with normal pancreatic tissue and that high P4HA1 expression correlates with poor patient prognosis. To further interrogate the role of P4HA1 in invasion of hypoxic patient-derived organoids, we quantified invasion in organoids modified to knockdown or overexpress P4HA1, demonstrating that P4HA1 is necessary for hypoxia-enhanced invasion and sufficient to increase invasion in normoxia in PDAC organoids. Our results identify P4HA1 as a driver of PDAC organoid invasion in hypoxia.

[SIGNIFICANCE] This study demonstrates that hypoxia increases invasion across a cohort of human pancreatic cancer organoids and identifies the collagen-modifying enzyme P4HA1 as a driver of hypoxia-enhanced invasion. These results characterize a molecular mechanism by which the microenvironment alters tumor cell behavior and underscore new strategies to inhibit invasion.