G-protein coupled receptor-associated sorting protein 1 (GASP-1), a ubiquitous tumor marker, promotes proliferation and invasion of triple negative breast cancer
Zheng, X. et al. (2022) G-protein coupled receptor-associated sorting protein 1 (GASP-1), a ubiquitous tumor marker, promotes proliferation and invasion of triple negative breast cancer. Exp. Mol. Pathol. 125, 104751. DOI: https://doi.org/10.1016/j.yexmp.2022.104751
G-protein coupled receptors (GPCRs) constitute a large family of eukaryotic cell-surface receptors, characterized structurally by crossing the cell membrane seven times. They are involved in several important signaling pathways, and aberrant GPCR expression is associated with many diseases. The GPCR-associated sorting protein-1 (GASP-1) regulates multiple GPCRs through both ligand-dependent and ligand-independent mechanisms.
Previously, researchers identified GASP-1 as a novel biomarker for breast cancer and showed that GASP-1 is overexpressed in breast cancer tumors, as well as other tumors. In this study, they proposed to determine the function of GASP-1 in breast cancer progression.
In triple-negative breast cancer (TNBC) cell lines, the researchers found that anti-GASP-1 antibodies inhibited cell growth; further, transient downregulation of GASP-1 greatly inhibited cell proliferation. Using stably transfected cells designed to over- and under-express GASP-1, they showed that GASP-1 downregulation promoted cell death. GASP-1 promoted cell invasion in two different assays that mimicked cell invasion in the tumor environment. Further, the size of GASP-1 granules, formed in the cytoplasm after overexpression of GASP-1, were predictive of which tumors became invasive. The researchers conclude that GASP-1 is a breast cancer biomarker with prognostic as well as therapeutic potential.
Keywords: G-protein coupled receptor-associated sorting protein 1, cancer markers, breast cancer, triple negative breast cancer, cancer progression, cancer invasion
