Beta1,4-galactosyltransferase V A growth regulator in glioma

Identification of a Glycosyltransferase Signature for Predicting Prognosis and Immune Microenvironment in Neuroblastoma

Neuroblastoma (NB) is one of the most common solid tumors in children. Glycosyltransferases (GTs) play a crucial role in tumor development and immune escape and have been used as prognostic biomarkers in various tumors. However, the biological functions and prognostic significance of GTs in NB remain poorly understood. The expression data from Gene Expression Omnibus (GEO) and Therapeutically Applicable Research to Generate Effective Treatments (TARGET) were collected as training and testing data. Based on a progression status, differentially expressed GTs were identified. We constructed a GTscore through support vector machine, least absolute shrinkage and selection operator, and Cox regression in NB, which included four prognostic GTs and was an independent prognostic risk factor for NB. Patients in the high GTscore group had an older age, MYCN amplification, advanced International Neuroblastoma Staging System stage, and high risk. Samples with high GTscores revealed high disialoganglioside (GD2) and neuron-specific enolase expression levels. In addition, a lack of immune cell infiltration was observed in the high GTscore group. This GTscore was also associated with the expression of chemokines (CCL2, CXCL9, and CXCL10) and immune checkpoint genes (cytotoxic T-lymphocyte–associated protein 4, granzyme H, and granzyme K). A low GTscore was also linked to an enhanced response to anti–PD-1 immunotherapy in melanoma patients, and one type of tumor was also derived from neuroectodermal cells such as NB. In conclusion, the constructed GTscore revealed the relationship between GT expression and the NB outcome, GD2 phenotype, and immune infiltration and provided novel clues for the prediction of prognosis and immunotherapy response in NB.

The miR‑625‑3p/AXL axis induces non‑T790M acquired resistance to EGFR‑TKI via activation of the TGF‑β/Smad pathway and EMT in EGFR‑mutant non‑small cell lung cancer

Gefitinib is currently the preferred treatment for non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR)-activating mutation. However, some patients gradually develop acquired resistance after receiving treatment. In addition to secondary T790M mutation, the remaining mechanisms contributing to non-T790M mutations need to be explored. In the present study, NSCLC-derived HCC827 and PC-9 cells and the corresponding gefitinib-resistant cell lines (HCC827GR and PC9GR) were utilized. Next-generation DNA sequencing was performed on the HCC827GR and PC9GR cells. Under AXL receptor tyrosine kinase (AXL) knockdown or miR-625-3p overexpressing conditions, a cell growth inhibition assay was performed to evaluate gefitinib sensitivity. Wound healing and Transwell assays were used to examine the migratory and invasive abilities of the cells. Moreover, we also carried out western blot analysis to detect the altered downstream signaling pathway. Our study revealed markedly decreased miR-625-3p expression in the HCC827GR cell line, while its overexpression partly reversed gefitinib resistance. Integrated analysis based on Targetscan website showed that AXL can be potentially targeted by miR-625-3p and we further verified the hypothesis via dual-luciferase reporter assays. Mechanistic analysis revealed that TGF-β1-induced EMT may contribute to the miR-625-3p/AXL axis-mediated gefitinib resistance. Our data demonstrated that miR-625-3p contributes to the acquired resistance of gefitinib, which may provide novel insight to combat resistance to EGFR-TKIs.

The Immunological Regulation Roles of Porcine β-1, 4 Galactosyltransferase V (B4GALT5) in PRRSV Infection

B4GALT5, also known as β-1, 4 galactosyltransferase V, is one of the members of β-1, 4 galactosyltransferase gene (B4GALT) family, which was concerned with embryonic development, tumor generation, other malignant diseases. In this study, we firstly cloned porcine B4GALT (pB4GALT5) from porcine alveolar macrophages, and predicted the structural domain and function of seven porcine β-1, 4 galactosyltransferase (I–VII) based on transcriptome analysis of PRRSV infected cells. Additionally, the upregulated porcine B4GALT5 expression was detected from PRRSV infected porcine alveolar macrophage (PAM) cells. The PRRSV proliferation were slightly inhibited in overexpression of pB4GALT5 transfected cells, the interaction of B4GALT5 and GP5 of PRRSV was firstly be detected by Co-IP, and the co-location between B4GALT5 and GP5 were also observed in golgi membranes by confocal microscopy. A significant increasing mRNA transcription, including inflammatory cytokines (IFN-α, IL-6, IL-18, IL-1β, TNF-α) and some cell surface glycosylated protein involved in antigen present (MHC-I/II), cell adhesion and migration (chemokine MCP-1 and receptor CCR2; LFA-1, ICAM-1) were upregulated in B4GALT5 overexpressed PRRSV infected cells. Our results demonstrated that the regulation of pB4GALT5 plays an important roles in PRRSV proliferation and modification function in viral infection cells. And these results will make achievements by supporting the research of latent mechanisms of β-1, 4 galactosyltransferase V in antiviral immunity.

High expression of β3GnT8 is associated with the metastatic potential of human glioma

Changes in glycosylation due to specific alterations of glycosyltransferase activity have been shown in various tumor cells, including human glioma cells. β1,3-N‑acetylglucosaminyltransferase-8 (β3GnT8) catalyzes the formation of polylactosamine on β1-6 branched N-glycans. Upregulated expression of β3GnT8 was described in some tumors, but its precise role in regulating glioma invasion and metastasis remains unclear. In this study, we report on an investigation of the expression of β3GnT8 in human glioma by immunohistochemical analysis. Out of 42 glioma tissues, 37 (88.1%) showed positive β3GnT8 expression, which was significantly higher than that in normal brain tissues (P<0.001). Additionally, the level of β3GnT8 increased with increased pathological grade of gliomas. Silencing of β3GnT8 in U251 glioma cells attenuated the formation of polylactosamine, and decreased cell proliferation, migration and metastatic ability in vitro and in vivo. By contrast, the overexpression of β3GnT8 in U251 cells exhibited enhanced metastatic potential. A positive correlation between β3GnT8 and matrix metalloproteinase-2 (MMP-2) expression in U251 cells was also observed. The results demonstrated a critical role of β3GnT8 in the metastatic potential of glioma cells, indicating that manipulating β3GnT8 expression may have therapeutic potential for the treatment of malignant glioma.

Role of sp transcription factors in the regulation of cancer cell metabolism

Cancer cells exhibit altered metabolism characterized by the generation of adenosine triphosphate by glycolysis and generation of fatty acids by de novo synthesis. The majority of genes involved in these pathways have binding sites for specificity protein (Sp) transcription factors in their promoters. Studies showing that Sp transcription factors, particularly Sp1, are involved in the regulation in cancer cells of hexokinase, pyruvate kinase, lactate dehydrogenase, fatty acid synthase, and hypoxia-inducible factor-1α are reviewed. Glycolysis and lipogenesis in cancers are also known to be stimulated by the constitutive activation of the PI3K/Akt signaling pathway. Evidence is presented for the notion that Sp transcription factors may act in concert with Akt to regulate the abnormal metabolism of cancer cells.