GRP78 regulates CD44v membrane homeostasis and cell spreading in tamoxifen-resistant breast cancer.

ABSTRACT: GRP78 conducts protein folding and quality control in the ER and shows elevated expression and cell surface translocation in advanced tumors. However, the underlying mechanisms enabling GRP78 to exert novel signaling functions at cell surface are just emerging. CD44 is a transmembrane protein and an important regulator of cancer metastasis, and isoform switch of CD44 through incorporating additional variable exons to the extracellular juxtamembrane region is frequently observed during cancer progression. Using super-resolution dual-color single-particle tracking, we report that GRP78 interacts with CD44v in plasma membrane nanodomains of breast cancer cells. We further show that targeting cell surface GRP78 by the antibodies can effectively reduce cell surface expression of CD44v and cell

SUBMITTER: Tseng CC 

PROVIDER: S-EPMC6696983 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature