YIPF2 is a novel Rab-GDF that enhances HCC malignant phenotypes by facilitating CD147 endocytic recycle.

An increased surface level of CIE (clathrin-independent endocytosis) proteins is a new feature of malignant neoplasms. CD147 is a CIE glycoprotein highly up-regulated in hepatocellular carcinoma (HCC). The ability to sort out the early endosome and directly target the recycling pathway confers on CD147 a prolonged surface half-life.

GRP75 modulates oncogenic Dbl-driven endocytosis derailed via the CHIP-mediated ubiquitin degradation pathway.

Chaperone-assisted proteasome degradation of oncogenic protein acts as an upstream signal controlling tumorigenesis and progression. The understanding of the co-regulation of chaperone and oncoprotein of endocytosis pathways is extremely limited. In this study, we showed for the first time that proto-Dbl (dbl proto-oncogene product) is co-enriched with mitochondrial chaperone GRP75 in endocytosis vesicles from ovarian cancer cells.

Macropinocytosis activated by oncogenic Dbl enables specific targeted delivery of Tat/pDNA nano-complexes into ovarian cancer cells.

Background: Successful implementation of gene therapy heavily relies on efficiently delivering genetic materials and specific targeting into cells. Oncogene-driven endocytosis stimulates nutrient uptake and also develops an endocytosis-mediated defense against therapeutic agents. Cell-penetrating peptides, typically HIV-Tat, are well known for efficient delivery of nucleic acid drugs but lack targeting specificity.

Mitochondria chaperone GRP75 moonlighting as a cell cycle controller to derail endocytosis provides an opportunity for nanomicrosphere intracellular delivery.

Understanding how cancer cells regulate endocytosis during the cell cycle could lead us to capitalize this event pharmacologically. Although certain endocytosis pathways are attenuated during mitosis, the endocytosis shift and regulation during the cell cycle have not been well clarified. The conventional concept of glucose-regulated proteins (GRPs) as protein folding chaperones was updated by discoveries that translocated GRPs assume moonlighting functions that modify the immune response, regulate viral release, and control intracellular trafficking.

[Mitochondrial signal peptide guides EGFP-GRP75 fusion proteins into mitochondria].

Objective To investigate the role of mitoch-ondrial signal peptide in guiding enhanced green fluorescent protein-glucose-regulated protein 75 fusion proteins (EGFP-GRP75) into mitochondria. Methods At first, the signal peptide gene and GRP75 domain genes were spliced by overlap extension PCR. Unphosphorylatable mutant T62A/S65A, phospho-mimic mutant T62D/S65D and substrate binding-defective mutant V482F were further created through site-directed mutagenesis PCR.