Shuai Liu

Core fucosylation of NCEH1 by FUT8 promotes progression of high-grade serous ovarian cancer by driving tumor-associated macrophage M2 polarization

High-grade serous ovarian cancer (HGSC) is the most aggressive subtype of ovarian epithelial cancer (OEC), with characters of late-stage diagnosis, high recurrence rate, and poor survival outcomes. Fucosyltransferase 8 (FUT8) is responsible for α1,6-core fucosylation biosynthesis, and aberrant FUT8/α1,6-core fucosylation level is involved in tumor progression. However, the roles and mechanisms of protein FUT8 and α1,6-core fucosylation in HGSC tumorigenesis and progression remain elusive. Here, our study confirms that elevated levels of FUT8/α1,6-core fucose in the tissues and serum of HGSC patients, and the elevation is associated with poor patient prognosis. By applying glycoproteomic assay, we globally screen and identify NCEH1 as the specific scaffold protein of α1,6-core fucosylation. Alpha 1,6-core fucose modification stabilizes NCEH1 by preventing its degradation through proteasomal pathway. Importantly, combined with non-targeted metabolomics analysis, α1,6-core fucosylated NCEH1 facilitates LPA secretion, driving M2-like polarization of tumor-associated macrophages in the tumor microenvironment, thus leading to oncogenesis and peritoneal metastasis of HGSC in vitro and in vivo. These findings broaden the understanding of FUT8/α1,6-core fucosylation/NCEH1 in HGSC progression and metastasis, and offer glycosylated diagnostic indicators and targets for therapeutic strategies in HGSC.

ALG3 Promotes Peritoneal Metastasis of Ovarian Cancer through Increasing Interaction of α1,3-mannosylated uPAR and ADAM8

Peritoneal metastasis is the main cause of poor prognoses and high mortality in ovarian cancer patients. Abnormal protein glycosylation modification is associated with cancer malignancy. Elevated α1,3-mannosyltransferase 3 (ALG3), which catalyzes the α1,3-mannosylation of glycoproteins, has been found in some malignant tumors. However, the pathological significance of ALG3 and its regulatory mechanism in ovarian cancer metastasis is unclear. The results showed that the level of ALG3/α1,3-mannosylation was higher in human ovarian cancer tissues compared with normal ovarian tissues, as measured by Lectin chip, Western blot and Lectin blot analyses, as well as ovarian tissue microarray analysis. ALG3 was also correlated with the poor prognosis of ovarian cancer patients, according to survival analysis. The downregulation of ALG3 decreased the proliferation, stemness and peritoneal metastasis of ovarian cancer cells. The increase in urokinase plasminogen activator receptor (uPAR) α1,3-mannosylation catalyzed by ALG3 enhanced urokinase plasminogen activator (uPA)/uPAR activation and the interaction of uPAR with a disintegrin and metalloproteinase 8 (ADAM8), which promoted ovarian cancer peritoneal metastasis via the ADAM8/Ras/ERK pathway. Furthermore, decreased ALG3 suppressed ascites formation and the peritoneal metastasis of ovarian cancer cells in mice. This study highlights ALG3 as a potential diagnostic biomarker and prospective therapeutic target for ovarian cancer.