Multi-omics integrative analysis to access role of coiled-coil domain-containing 80 in lipid metabolism.

Coiled-coil domain-containing 80 (Ccdc80) is closely linked to energy homeostasis. However, the molecular mechanism remains unclear. This study aims to uncover the potential mechanism of Ccdc80 in modulating lipid metabolism by accessing the metabolic and transcriptional consequences of removing Ccdc80. We established a Ccdc80 knockout model (Ccdc80-/-) in C57BL/6 mouse. Serum and liver samples from Ccdc80+/+ (n = 8) and Ccdc80-/- (n = 8) male mice were obtained at the age of week 10. The serum metabolites and lipids were analyzed by gas chromatography-mass spectrometry and ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, respectively. RNA expression microarray was performed in the livers of the same mice. Results showed that a total of 58 metabolites and 30 lipids were altered between the Ccdc80+/+ and Ccdc80-/- mice. A total of 873 hepatic differentially expressed genes (DEGs) were identified. The enrichment analysis of discriminant metabolites and lipids reflected alterations in α-linolenic acid and linoleic acid metabolism. Reactome pathway analysis of DEGs revealed a decreased hydroxylation of arachidonic acid in Ccdc80-/- mice. The Kyoto Encyclopedia of Genes and Genomes pathway result suggested a decrease of PPAR signaling and fatty acid degradation by Ccdc80-knockout. The joint pathway analysis integrating metabolomics, lipidomics and transcriptomics indicated that Ccdc80-knockout could down-regulate arachidonic acid and α-linolenic acid metabolism. These results provide new insights into the role of Ccdc80 in fatty acid metabolism.

Deficiency of coiled-coil domain containing 80 increases plasma cholesterol by decreasing fecal sterols excretion in hypercholesterolemic mice.

Disorders in cholesterol and bile acid metabolism have been acknowledged as critical in pathogenesis of hypercholesterolemia. Coiled-coil domain containing 80 (CCDC80) has been closely linked to lipid homeostasis in mice, with its role in cholesterol metabolism yet to be fully elucidated. This study aims to uncover the regulatory mechanisms of CCDC80 in diet-induced hypercholesterolemia. We generated a CCDC80 knockout (CCDC80-/-) model in C57BL/6 mouse. The initial transcriptional and metabolic consequences of removing CCDC80 were accessed at baseline by gene expression microarrays and gas chromatography-mass spectrometry / ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, respectively. The hepatic cholesterol was investigated in both CCDC80+/+ and CCDC80-/- male mice at baseline and after feeding a high-cholesterol diet for 12 weeks. The regulatory effects of CCDC80 on gene expressions and protein masses were measured by RT-qPCR and western blot, respectively. At baseline, the KEGG pathway enrichment analysis combining metabolomics, lipidomics and transcriptomics, revealed a down-regulation of hepatic bile acid biosynthesis by CCDC80-knockout, especially for primary bile acids. In the hypercholesterolemic models, our results showed that deficiency of CCDC80 increased plasma and liver cholesterol levels, but decreased fecal neutral and acidic sterols excretion in mice. Mechanistically, we found that such effects were partly mediated by attenuating the alternative pathway of bile acid synthesis catalyzed by oxysterol 7-alpha-hydroxylase (CYP7B1). In conclusion, our results suggest CCDC80 as a novel modulator of cholesterol homeostasis in male mice. Deficiency of CCDC80 could further impair fecal sterols excretion in diet-induced hypercholesterolemia.

The function of FAK/CCDC80/E-cadherin pathway in the regulation of B16F10 cell migration.

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase involved in the development and progression of cancer. However, the regulatory role of FAK in cell migration remains unclear. The aim of the present study was to investigate the mechanism underlying the regulation of melanoma cell migration by FAK. The effect of FAK knockdown on gene expression in B16F10 cells was examined by gene chip analysis. The expression levels of coiled-coil domain containing 80 (CCDC80) and epithelial (E)-cadherin were analyzed by reverse transcription quantitative polymerase chain reaction and western blotting. Wound healing and transwell assays were used to monitor B16F10 cell migration. It was identified that the knockdown of FAK increased the expression levels of CCDC80 and E-cadherin, while the overexpression of CCDC80 elevated E-cadherin expression. Concurrently, upregulation of CCDC80 inhibited the migration of B16F10 cells, and downregulation of CCDC80 promoted the migration of B16F10 cells. The clinical data from the Oncomine database also revealed that the mRNA level of FAK was increased while the mRNA levels of CCDC80 and E-cadherin were decreased in patients with melanoma compared with normal controls. Taken together, the results of the present study suggest that the regulation of B16F10 melanoma cell migration by FAK is potentially mediated by CCDC80.