Ergolide Mediates Anti-Cancer Effects on Metastatic Uveal Extra Cellular Vesicles: Melanoma Cells and Modulates their Cell Lysate and Extracellular Vesicle proteomes.

ABSTRACT: Uveal melanoma is a poor prognosis cancer with an imperative need for new treatment options. Ergolide, a sesquiterpene lactone isolated from the flowers of Inula species (a medicinal herb), exerts anti-cancer properties. The objective of this study was to 1) evaluate whether ergolide reduced metastatic uveal melanoma (MUM) cell survival/viability in vitro and in vivo; and 2) to understand the molecular mechanism of ergolide action. Ergolide treatment resulted in significant dose-dependent reduction (48.5 to 99.9%; p < 0.0001) in OMM2.5 cell survival in vitro and of normalized primary zebrafish xenograft fluorescence (56%; p< 0.0001) in vivo, compared to vehicle controls. Proteome profiling of ergolide treated OMM2.5 cells, identified 5023 proteins in total with 52 and 55 proteins significantly altered at 4 hours and 24 hours, respectively (p value <0.05; fold-change >1.2). Immunoblot analysis of heme oxygenase 1 (HMOX1), growth/differentiation factor 15 (GDF15) and macrophage migration inhibitory factor (MIF) corroborated the proteomics data. MIF was distinctly downregulated following ergolide treatment. Proteomics of EVs isolated from OMM2.5 cells treated with ergolide detected 2931 total proteins, 2679 of which are recognized as EV proteins based on the Vesiclepedia compendium. 252 additional putative novel EV proteins were also identified. Within the differentially expressed proteins, the proteasomal pathway was primarily altered. Interestingly, BRCA2 and CDKN1A Interacting Protein (BCCIP) and Chitinase Domain Containing 1 (CHID1), were the only proteins significantly differentially expressed by ergolide in both the OMM2.5 cell and EV isolates and they displayed inverse differential expression in the cells versus the EVs. In the TCGA database, no significant correlations occurred between BCCIP and CHID1 transcript levels and overall survival or disease-free survival in UM patients. Ergolide is a novel candidate that shows promise as an anti-proliferative agent for UM/MUM cells. Proteomic profiling of OMM2.5 cell lysates and EVs identified candidate pathways elucidating the action of ergolide and putative biomarkers of UM, that require further examination.

INSTRUMENT(S): Bruker Daltonics timsTOF series

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Melanocyte, Cell Culture

DISEASE(S): Uveal Melanoma

SUBMITTER: Kieran Wynne  

LAB HEAD: Professor Breandán Kennedy

PROVIDER: PXD042510 | Pride | 2023-08-15

REPOSITORIES: Pride