Secretion of the disulfide bond generating catalyst QSOX1 from pancreatic tumor cells into the extracellular matrix: association with extracellular vesicles and matrix proteins.

ABSTRACT: Quiescin sulfhydryl oxidase 1 (QSOX1) is a disulfide bond generating catalyst that is overexpressed in solid tumors. Expression of QSOX1 is linked to cancer cell invasion, tumor grade, and extracellular matrix (ECM) protein deposition. While the secreted version of QSOX1 is known to be present in various fluids and secretory tissues, its presence in the ECM of cancer is less understood. To characterize secreted QSOX1, we separated conditioned media based on size and density. We discovered that the majority of secreted QSOX1 resides in the EV-depleted fraction and in the soluble protein fraction. Very little QSOX1 could be detected in the EVP fraction. We used immunofluorescence to image subpopulations of EVs and found QSOX1 in Golgi-derived vesicles and medium/large vesicles, but in genera

SUBMITTER: Millar-Haskell CS 

PROVIDER: S-EPMC9797115 | biostudies-literature | 2022 Jul

REPOSITORIES: biostudies-literature