Biology subjects

Danen, E. H. J.

Publications and source records attributed to Danen, E. H. J..

4 recordsLinked to original sources

bioRxiv2026

Septins promote breast cancer cell invasion in 3D collagen gels by influencing actin-based protrusion formation

Septins are cytoskeletal proteins that contribute to essential cellular processes such as cell migration and cell division through interactions with the cell membrane and the cytoskeleton. High expression of septins is correlated with breast cancer malignancy and promotes cell invasion, but the molecular complexity of septins interactions has made it challenging to dissect the underlying molecular mechanisms. Here, we used a conditional knockout approach to deplete SEPT7 in the metastatic triple-negative breast cancer cell line Hs578T and examined the role of septin in 3D-matrix invasion of breast cancer cells. We show by spheroid assays that SEPT7 deletion strongly impairs breast cancer cell invasion into collagen gels. Additional single-cell migration studies using 3D collagen gels and microfluidic pillar devices that mimic the pores present in collagen matrices showed that SEPT7 expression regulates confined cell migration through control of cell shape and actin-based protrusions.

cancer biology↗

bioRxiv2024

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

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.

biophysics↗

bioRxiv2024

TCR-engineered T-cells directed against Ropporin-1 constitute a safe and effective treatment for triple-negative breast cancer in near-clinical models

Triple-negative breast cancer (TNBC) shows an urgent need for new therapies. We discovered Ropporin-1 (ROPN1) as a target to treat TNBC with T-cells. ROPN1 showed high and homogenous expression in 90% of primary and metastatic TNBC but not in healthy tissues. HLA-A2-binding peptides were detected via immunopeptidomics and predictions and used to retrieve T-cell receptors (TCRs) from naive repertoires. Following gene introduction into T-cells and stringent selection, we retrieved a highly specific TCR directed against the epitope FLYTYIAKV that did not recognize non-cognate epitopes from alternative source proteins. Notably, this TCR mediated killing of three-dimensional tumoroids in vitro and tumor cells in vivo and outperformed standard-of-care drugs. Finally, the T-cell product expressing this TCR and manufactured using a clinical protocol fulfilled standard safety and efficacy assays. Collectively, we have identified and preclinically validated ROPN1 as a target and anti-ROPN1 TCR T-cells as a treatment for the vast majority of TNBC patients.

immunology↗

bioRxiv2023

ABCB1 overexpression through locus amplification represents an actionable target to combat paclitaxel resistance in pancreatic cancer cells

AimsChemotherapies such as gemcitabine/nab-paclitaxel are confronted with intrinsic or acquired resistance in pancreatic ductal adenocarcinoma (PDAC). We aimed to identify novel actionable mechanisms to overcome such resistance. MethodsThree paclitaxel (PR) and gemcitabine resistant (GR) PDAC models were established. Transcriptomics and proteomics were used to identify conserved mechanisms of drug resistance. Genetic and pharmacological approaches were used to overcome paclitaxel resistance. ResultsUpregulation of ABCB1 through locus amplification was identified as a conserved feature unique to PR cells. ABCB1 was not affected in any of the GR models and no cross resistance was observed. The ABCB1 inhibitor verapamil or siRNA mediated ABCB1 depletion sensitized PR cells to paclitaxel and prevented efflux of ABCB1 substrates in all models. ABCB1 expression was detected in PDAC patients that had received gemcitabine/nab-paclitaxel treatment. A pharmacological screen identified known and novel kinase inhibitors that attenuate efflux of ABCB1 substrates and sensitize PR PDAC cells to paclitaxel. ConclusionUpregulation of ABCB1 through locus amplification represents a novel, conserved mechanism of PDAC paclitaxel resistance. ABCB1 has not been previously implicated in PR PDAC. The synthetic lethal interactions identified in this study can be further (pre)clinically explored as therapeutic strategies to overcome paclitaxel resistance in PDAC.

cancer biology↗