Altered Mechanobiology of PDAC Cells with Acquired Chemoresistance to Gemcitabine and Paclitaxel.

Abstract

BackgroundPancreatic ductal adenocarcinoma (PDAC) acquired resistance to chemotherapy poses a major limitation to patient survival. Despite understanding of some biological mechanisms of chemoresistance, much of those mechanisms remain to be uncovered. Mechanobiology, which studies physical properties of cells, holds promise as a potential target for addressing challenges of chemoresistance in PDAC. Therefore, we here in an initial step, assessed the altered mechanobiology of PDAC cells with acquired chemoresistance to gemcitabine and paclitaxel. MethodsFive PDAC cell lines and six stably-resistant subclones were assessed for force generation on elastic micropillar arrays. Those measurements of mechanical phenotype were complemented by single-cell motility and invasion in collagen matrix were investigated using 2D models and 3D extracellular matrix-mimetic, respectively. Further the nuclear translocation of Yes-associted protein (YAP), as a measure of active mechanical status, was compared, and biomarkers of the epithelial-to-mesenchymal transition (EMT) were evaluated using RT-PCR. ResultsPDAC cells with acquired chemoresistance exert higher traction forces than their parental/wild-type (WT) cells. In 2D, single-cell motility was altered for all chemoresistant cells, with a cell-type specific pattern. In 3D, spheroids of chemoresistant PDAC cells were able to invade the matrix, and remodel collagen more than their WT clones. However, YAP nuclear translocation and EMT were not significantly altered in relation to changes in other physical parameters. ConclusionThis is the first study to investigate and report on the altered mechanobiological features for PDAC cells that have acquired chemoresistance. A better understanding of mechanical features could help in identifying future targets to overcome chemoresistance in PDAC.