ABSTRACT
[This corrects the article DOI: 10.7150/ijbs.29048.].
ABSTRACT
Polypeptide N-acetylgalactosaminyl transferase-6 (GALNT6), a member of the N-acetyl-D-galactosamine transferase family, was shown to be over-expression in mammary cancer and could be used as a biomarker. However, its roles and underlying mechanisms in the pathogenesis of breast cancer are still unclear. In this study, we reported that GALNT6 was up-expression in breast cancer, and it was not associated with tumor stage. The expression level of GALNT6 and menopause status was associated with patient survival. Biological function results illustrated that knockdown of GALNT6 inhibited proliferation, migration and invasion of MDA-MB-231 cells, and increased cell apoptosis. Knockdown of GALNT6 in breast cancer cell attenuated the protein expression of PCNA, cyclin D1, C-myc and ß-catenin, and increased the expression of E-cadherin, caspase 3 and cleaved PARP1. Cell fractionation assay showed that knockdown of GALNT6 reduced the levels of ß-catenin and MUC1-C in nucleus. Simultaneously knockdown of GALNT6 and ß-catenin significantly reduced the level of C-myc. Co-IP experiments indicated that GALNT6 interacted with MUC1-N, ß-catenin interacting with MUC1-C in breast cancer cells. Together, our study reveals that GALNT6 promotes tumorigenicity and metastasis through ß-catenin/MUC1-C signaling pathway.
Subject(s)
Apoptosis/physiology , Breast Neoplasms/metabolism , Cell Proliferation/physiology , N-Acetylgalactosaminyltransferases/metabolism , beta Catenin/metabolism , Animals , Apoptosis/genetics , Blotting, Western , Breast Neoplasms/genetics , Cell Line, Tumor , Cell Movement/genetics , Cell Movement/physiology , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic/genetics , Gene Expression Regulation, Neoplastic/physiology , Humans , Immunoprecipitation , MCF-7 Cells , Mice , Mice, Nude , N-Acetylgalactosaminyltransferases/genetics , Real-Time Polymerase Chain Reaction , Wound Healing/genetics , Wound Healing/physiology , beta Catenin/genetics , Polypeptide N-acetylgalactosaminyltransferaseABSTRACT
Fucosyltransferase 2 (FUT2), the enzyme catalyzing α-1,2-fucosylation in mammals, has been implicated in cancer. The up-regulation of FUT2 has been observed in lung adenocarcinoma (LUAD), and FUT2 can enhance the cell migration and invasion of LUAD cell lines. However, the underlying mechanism of FUT2 in LUAD remains largely unknown. Abundant studies have revealed that epithelial-mesenchymal transition (EMT) played a pivotal role during lung cancer metastasis and progression. In the present study, we showed that knocking down FUT2 in LUAD cell lines increased the expression of E-cadherin and reduced the expression of Vimentin, N-cadherin, TßRII, p-Smad2, p-Smad3 and Snail, which were the makers of EMT. Meanwhile, the expression of E-cadherin was decreased, and the expression of Vimentin was increased by restoring the expression of FUT2 in RNA interference FUT2 (RNAi-FUT2) cells, suggesting that FUT2 enhanced the EMT process in LUAD. Additionally, silencing FUT2 expression can up-regulate E-cadherin and down-regulate Vimentin, significantly attenuated EMT in vivo. Treated with the SIS3, a new-type inhibitor of p-Smad3 of TGF-ß signaling, the expression of E-cadherin, Vimentin and Snail were not affected by RNAi-FUT2 cells, indicating that the effect of FUT2 on EMT depended on TGF-ß/Smad signaling. Overall, the current results indicated that FUT2 might promote LUAD metastasis through the EMT initiated by TGF-ß/Smad signaling. Therefore, FUT2 might be a prognostic factor and therapeutic target for LUAD.
Subject(s)
Cadherins/drug effects , Cell Movement/drug effects , Epithelial-Mesenchymal Transition/drug effects , Fucosyltransferases/pharmacology , Transforming Growth Factor beta/drug effects , Cadherins/metabolism , Down-Regulation/drug effects , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Signal Transduction/drug effects , Transforming Growth Factor beta/metabolism , Transforming Growth Factor beta1/metabolism , Up-Regulation/drug effects , Vimentin/metabolism , Galactoside 2-alpha-L-fucosyltransferaseABSTRACT
This study was designed to investigate the antitumor effects of Sargassum fusiforme polysaccharides (SFPS) on nasopharyngeal carcinoma (NPC) and the underlying mechanism of its effect on splenic lymphocytes. As a result, SFPS significantly inhibited the growth of nasopharyngeal carcinoma CNE in vivo, and remarkably increased the serum cytokines and IgM levels in CNE-bearing mice. Meanwhile, SFPS stimulated the peritoneal macrophages to secrete the cytokines, exerted a stimulatory effect on splenic lymphocytes proliferation, and increased the expression of IgM from splenic lymphocytes. The pretreatment of splenic lymphocytes with special antibodies (anti-TLR4 and anti-TLR2) significantly suppressed the proliferation of splenic lymphocytes and blocked SFPS-induced IgM production. SB203580, a specific inhibitor of p38 MAPK, effectively suppressed SFPS-induced IgM secretion in splenic lymphocytes. Taken together, SFPS has antitumor and immunomodulatory activities in NPC, and its activity is mediated, at least in part, by TLR2/TLR4 receptors and p38 MAPK signaling pathway.