FUT family mediates the multidrug resistance of human hepatocellular carcinoma via the PI3K/Akt signaling pathway. Cell Death Dis. 2013;4:e923. [PMID: 24232099 PMCID: PMC3847326 DOI: 10.1038/cddis.2013.450]

Polymorphisms of FUT9 and its relationship with susceptibility towards DHAV-3 in Pekin duck

Duck viral hepatitis severely threatens the development of the duck industry, leading to economic losses every year. Using selected Pekin duck populations exhibiting varying resistance towards Duck Hepatitis A Virus type 3 (DHAV-3), screening for genetic variations, such as single nucleotide polymorphisms (SNP), associated with disease susceptibility will facilitate the breeding of Pekin ducks with enhanced disease resistance. The biological role of fucosyltransferases, which are a type of glycosyltransferase enzymes, is to catalyze the transfer of fucose to molecules such as oligosaccharides, glycoproteins and glycolipids, which is crucial for maintaining immune function by promoting effective pathogen recognition and modulating immune responses through specific fucosylation patterns. Previous studies found that the expression level of the Fucosyltransferase 9 (FUT9) gene in the liver of resistant Pekin ducks was significantly higher than that in susceptible ducks, suggesting its potential association with disease resistance. However, the association between genetic variations in FUT9 and susceptibility to DHAV-3 in ducks remains unclear. This study aims to detect SNPs in the FUT9 gene and explore their relationships with disease mortality and susceptibility, the result will provide a scientific basis for developing effective control strategies in duck breeding. 242 Pekin ducks with varying resistance to DHAV-3 were used in this experiment. 12 SNPs were identified in the coding region of FUT9. And g.76953686 T > C and g.76954451C > T were significantly associated with susceptibility to DHAV-3 in Pekin ducks. The results indicate that variations in the FUT9 gene significantly influence the susceptibility of ducks towards DHAV-3, providing potential genetic markers for enhancing disease resistance breeding in Pekin ducks.

Fucosyltransferase 4 upregulates P-gp expression for chemoresistance via NF-κB signaling pathway

BACKGROUND

Multidrug resistance (MDR) poses a significant obstacle to developing chemotherapeutic treatments. In previous studies using a traditional model of adriamycin resistance (ADR) with K562 cells, we demonstrated that N-acetylglucosaminyltransferase III (GnT-III) expression negatively regulates chemoresistance. Additionally, we observed that fucosylation levels were increased in the ADR cells.

METHOD

Fucosylation levels were determined using lectin blot, western blot, and flow cytometry. Gene expression levels were analyzed via qPCR. We generated a FUT4 knockout (KO) ADR cell line using CRISPR/Cas9 technology. Cytotoxicity and drug efflux assays were conducted to evaluate chemotherapy tolerance.

RESULTS

The expression levels of FUT4 and its products, the LeX antigens, were significantly upregulated in the ADR cells compared to the parental K562 cells. The FUT4 KO reduced the elevated levels of P-glycoprotein (P-gp) found in ADR cells and exhibited increased sensitivity to chemotherapeutic drugs. Furthermore, restoring FUT4 expression in the KO cells effectively reversed P-gp expression, drug efflux, and chemoresistance. Given the critical role of the NF-κB pathway in P-gp expression, we investigated NF-κB signaling and found that the phosphorylation levels of p65 were significantly increased in the ADR cells but were downregulated in the FUT4 KO cells. Furthermore, the restoration of FUT4 rescued the phosphorylation levels of p65.

CONCLUSIONS

FUT4 specifically upregulates P-gp expression related to chemoresistance through the NF-κB signaling pathway.

GENERAL SIGNIFICANCE

This study highlights the importance of FUT4 in chemoresistance and suggests it may serve as a promising target for combating MDR.

N-Linked Fucosylated Glycans Are Biomarkers for Prostate Cancer with a Neuroendocrine and Metastatic Phenotype

Prostate cancer is a heterogeneous disease with a spectrum of pathology and outcomes ranging from indolent to lethal. Although there have been recent advancements in prognostic tissue biomarkers, limitations still exist. We leveraged matrix-assisted laser desorption/ionization imaging of formalin-fixed, paraffin embedded prostate cancer specimens to determine if N-linked glycans expressed in the extracellular matrix of lethal neuroendocrine prostate cancer were also expressed in conventional prostate adenocarcinomas that were associated with poor outcomes. We found that N-glycan fucosylation was abundant in neuroendocrine prostate cancer as well as adenocarcinomas at the time of prostatectomy that eventually developed recurrent metastatic disease. Analysis of patient-derived xenografts revealed that this fucosylation signature was enriched differently across metastatic disease organ sites, with the highest abundance in liver metastases. These data suggest that N-linked fucosylated glycans could be an early tissue biomarker for poor prostate cancer outcomes. Implications: These studies identify that hyper-fucosylated N-linked glycans are enriched in neuroendocrine prostate cancer and conventional prostate adenocarcinomas that progress to metastatic disease, thus advancing biomarker discovery and providing insights into mechanisms underlying metastatic disease.

Interplay between de novo and salvage pathways of GDP-fucose synthesis

GDP-fucose is synthesised via two pathways: de novo and salvage. The first uses GDP-mannose as a substrate, and the second uses free fucose. To date, these pathways have been considered to work separately and not to have an influence on each other. We report the mutual response of the de novo and salvage pathways to the lack of enzymes from a particular route of GDP-fucose synthesis. We detected different efficiencies of GDP-fucose and fucosylated structure synthesis after a single inactivation of enzymes of the de novo pathway. Our study demonstrated the unequal influence of the salvage enzymes on the production of GDP-fucose by enzymes of the de novo biosynthesis pathway. Simultaneously, we detected an elevated level of one of the enzymes of the de novo pathway in the cell line lacking the enzyme of the salvage biosynthesis pathway. Additionally, we identified dissimilarities in fucose uptake between cells lacking TSTA3 and GMDS proteins.

FUCA1: An Underexplored p53 Target Gene Linking Glycosylation and Cancer Progression

Cancer is a difficult-to-cure disease with high worldwide incidence and mortality, in large part due to drug resistance and disease relapse. Glycosylation, which is a common modification of cellular biomolecules, was discovered decades ago and has been of interest in cancer research due to its ability to influence cellular function and to promote carcinogenesis. A variety of glycosylation types and structures regulate the function of biomolecules and are potential targets for investigating and treating cancer. The link between glycosylation and carcinogenesis has been more recently revealed by the role of p53 in energy metabolism, including the p53 target gene alpha-L-fucosidase 1 (FUCA1), which plays an essential role in fucosylation. In this review, we summarize roles of glycan structures and glycosylation-related enzymes to cancer development. The interplay between glycosylation and tumor microenvironmental factors is also discussed, together with involvement of glycosylation in well-characterized cancer-promoting mechanisms, such as the epidermal growth factor receptor (EGFR), phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt) and p53-mediated pathways. Glycan structures also modulate cell-matrix interactions, cell-cell adhesion as well as cell migration and settlement, dysfunction of which can contribute to cancer. Thus, further investigation of the mechanistic relationships among glycosylation, related enzymes and cancer progression may provide insights into potential novel cancer treatments.

An emerging role of N-glycosylation in cancer chemoresistance

Chemoresistance poses a significant obstacle in the effective treatment of cancer, limiting the success of chemotherapy regimens. N-glycosylation, the most important post-translational modification (PTM), plays multifaceted roles in the intricate landscape of cancer progression, particularly drug resistance in cancer cells. This review explores the complex relationship between N-glycosylation and chemoresistance in cancer. Altered glycosylation patterns have been proven to impact drug efflux mechanisms in cancer cells, which can further influence the intracellular concentration of chemotherapy drugs. Moreover, N-glycosylation also plays a regulatory role in cell signaling pathways and apoptosis regulators, continuously affecting the stemness and survival of cancer cells under the selective pressure of chemotherapy. Additionally, the impact of the tumor microenvironment on glycosylation patterns adds complexity to this interplay. This review discusses current research findings, challenges, and future directions based on the roles of N-glycosylation in cancer chemoresistance, emphasizing the potential for targeted therapeutic interventions to enhance the effectiveness of chemotherapy and improve patient outcomes.

Androgen drives melanoma invasiveness and metastatic spread by inducing tumorigenic fucosylation

Melanoma incidence and mortality rates are historically higher for men than women. Although emerging studies have highlighted tumorigenic roles for the male sex hormone androgen and its receptor (AR) in melanoma, cellular and molecular mechanisms underlying these sex-associated discrepancies are poorly defined. Here, we delineate a previously undisclosed mechanism by which androgen-activated AR transcriptionally upregulates fucosyltransferase 4 (FUT4) expression, which drives melanoma invasiveness by interfering with adherens junctions (AJs). Global phosphoproteomic and fucoproteomic profiling, coupled with in vitro and in vivo functional validation, further reveal that AR-induced FUT4 fucosylates L1 cell adhesion molecule (L1CAM), which is required for FUT4-increased metastatic capacity. Tumor microarray and gene expression analyses demonstrate that AR-FUT4-L1CAM-AJs signaling correlates with pathological staging in melanoma patients. By delineating key androgen-triggered signaling that enhances metastatic aggressiveness, our findings help explain sex-associated clinical outcome disparities and highlight AR/FUT4 and its effectors as potential prognostic biomarkers and therapeutic targets in melanoma.

Integrated analysis of high‑throughput sequencing reveals the regulatory potential of hsa_circ_0035431 in HNSCC

Circular RNAs (circRNAs) are molecular sponges that are involved in regulation of multiple types of cancer. The present study aimed to screen and explore the key circRNA/microRNA (miRNA or miR)/mRNA interactions in head and neck squamous cell carcinoma (HNSCC) using bioinformatics. A total of six pairs of cancerous and adjacent healthy tissue were obtained from patients with HNSCC and genome-wide transcriptional sequencing was performed. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed on differentially expressed genes (DEGs). Moreover, expression levels of DEGs were verified in HNSCC cells and tissues using reverse transcription-quantitative (RT-q)PCR. A molecular regulatory network consisting of three circRNAs, seven miRNAs and seven mRNAs was constructed, resulting in identification of two signaling axes, hsa_circ_0035431/hsa-miR-940/fucosyltransferase 6 (FUT6) and hsa_circ_0035431/hsa-miR-940/cingulin-like 1 (CGNL1). FUT6 and CGNL1 were downregulated in HNSCC compared with adjacent healthy tissue and the expression levels of these genes were associated with tumor stage. Low FUT6 and CGNL1 expression levels were associated with lower overall survival rate and progression-free intervals in HNSCC. RT-qPCR demonstrated that hsa_circ_0035431, FUT6 and CGNL1 were downregulated in HNSCC cells and tissue and hsa-miR-940 was upregulated. Notably, these results were consistent with those obtained using high-throughput sequencing. In conclusion, hsa_circ_0035431 may participate in regulation of FUT6 and CGNL1 expression by sponging hsa-miR-940, thus, impacting the occurrence, development and prognosis of HNSCC.

Core Fucosylation Mediated by the FucT-8 Enzyme Affects TRAIL-Induced Apoptosis and Sensitivity to Chemotherapy in Human SW480 and SW620 Colorectal Cancer Cells

Epithelial cells can undergo apoptosis by manipulating the balance between pro-survival and apoptotic signals. In this work, we show that TRAIL-induced apoptosis can be differentially regulated by the expression of α(1,6)fucosyltransferase (FucT-8), the only enzyme in mammals that transfers the α(1,6)fucose residue to the pentasaccharide core of complex N-glycans. Specifically, in the cellular model of colorectal cancer (CRC) progression formed using the human syngeneic lines SW480 and SW620, knockdown of the FucT-8-encoding FUT8 gene significantly enhanced TRAIL-induced apoptosis in SW480 cells. However, FUT8 repression did not affect SW620 cells, which suggests that core fucosylation differentiates TRAIL-sensitive premetastatic SW480 cells from TRAIL-resistant metastatic SW620 cells. In this regard, we provide evidence that phosphorylation of ERK1/2 kinases can dynamically regulate TRAIL-dependent apoptosis and that core fucosylation can control the ERK/MAPK pro-survival pathway in which SW480 and SW620 cells participate. Moreover, the depletion of core fucosylation sensitises primary tumour SW480 cells to the combination of TRAIL and low doses of 5-FU, oxaliplatin, irinotecan, or mitomycin C. In contrast, a combination of TRAIL and oxaliplatin, irinotecan, or bevacizumab reinforces resistance of FUT8-knockdown metastatic SW620 cells to apoptosis. Consequently, FucT-8 could be a plausible target for increasing apoptosis and drug response in early CRC.

Core fucosylation and its roles in gastrointestinal glycoimmunology

Glycosylation is a common post-translational modification in eukaryotic cells. It is involved in the production of many biologically active glycoproteins and the regulation of protein structure and function. Core fucosylation plays a vital role in the immune response. Most immune system molecules are core fucosylated glycoproteins such as complements, cluster differentiation antigens, immunoglobulins, cytokines, major histocompatibility complex molecules, adhesion molecules, and immune molecule synthesis-related transcription factors. These core fucosylated glycoproteins play important roles in antigen recognition and clearance, cell adhesion, lymphocyte activation, apoptosis, signal transduction, and endocytosis. Core fucosylation is dominated by fucosyltransferase 8 (Fut8), which catalyzes the addition of α-1,6-fucose to the innermost GlcNAc residue of N-glycans. Fut8 is involved in humoral, cellular, and mucosal immunity. Tumor immunology is associated with aberrant core fucosylation. Here, we summarize the roles and potential modulatory mechanisms of Fut8 in various immune processes of the gastrointestinal system.

Fucosyltransferase 5 Promotes the Proliferative and Migratory Properties of Intrahepatic Cholangiocarcinoma Cells via Regulating Protein Glycosylation Profiles

Background

The incidence of intrahepatic cholangiocarcinoma (ICC) is increasing globally, and its prognosis has not improved substantially in recent years. Understanding the pathogenesis of ICC may provide a theoretical basis for its treatment. In this study, we investigated the effects and underlying mechanisms of fucosyltransferase 5 (FUT5) on the malignant progression of ICC.

Methods

FUT5 expression in ICC samples and adjacent nontumor tissues was compared using quantitative real-time polymerase chain reaction and immunohistochemical assays. We performed cell counting kit-8, colony formation, and migration assays to determine whether FUT5 influenced the proliferation and mobility of ICC cells. Finally, mass spectrometry was performed to identify the glycoproteins regulated by FUT5.

Results

FUT5 mRNA was significantly upregulated in most ICC samples compared with corresponding adjacent nontumor tissues. The ectopic expression of FUT5 promoted the proliferation and migration of ICC cells, whereas FUT5 knockdown significantly suppressed these cellular properties. Mechanistically, we demonstrated that FUT5 is essential for the synthesis and glycosylation of several proteins, including versican, β3 integrin, and cystatin 7, which may serve key roles in the precancer effects of FUT5.

Conclusions

FUT5 is upregulated in ICC and promotes ICC development by promoting glycosylation of several proteins. Therefore, FUT5 may serve as a therapeutic target for the treatment of ICC.

Protein glycosylation alterations in hepatocellular carcinoma: function and clinical implications

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. Understanding the cancer mechanisms provides novel diagnostic, prognostic, and therapeutic markers for the management of HCC disease. In addition to genomic and epigenomic regulation, post-translational modification exerts a profound influence on protein functions and plays a critical role in regulating various biological processes. Protein glycosylation is one of the most common and complex post-translational modifications of newly synthesized proteins and acts as an important regulatory mechanism that is implicated in fundamental molecular and cell biology processes. Recent studies in glycobiology suggest that aberrant protein glycosylation in hepatocytes contributes to the malignant transformation to HCC by modulating a wide range of pro-tumorigenic signaling pathways. The dysregulated protein glycosylation regulates cancer growth, metastasis, stemness, immune evasion, and therapy resistance, and is regarded as a hallmark of HCC. Changes in protein glycosylation could serve as potential diagnostic, prognostic, and therapeutic factors in HCC. In this review, we summarize the functional importance, molecular mechanism, and clinical application of protein glycosylation alterations in HCC.

Molecular and metabolic mechanisms of bufalin against lung adenocarcinoma: New and comprehensive evidences from network pharmacology, metabolomics and molecular biology experiment

BACKGROUND

This study aims to evaluate the efficacy and therapeutic mechanism of bufalin on lung adenocarcinoma (LUAD) through a comprehensive strategy integrating network pharmacology, metabolomics and molecular biology verification.

METHODS

The putative targets of bufalin were discerned from PharmMapper and Swiss Target Prediction database. LUAD-related targets were obtained by target filtering of GeneCard database and data mining of GEO database. PPI network was constructed to screen the core targets, and their clinical significance was assessed through several public databases. GO and KEGG pathway analyses were performed to identify possible enrichment of genes with specific biological themes. Molecular docking and molecular dynamics (MD) simulation were employed to determine the correlation and binding pattern between bufalin and core targets. The potential mechanisms of bufalin acting on LUAD, as predicted by network pharmacology analyses, were experimentally validated using in-vitro and in-vivo models. Finally, the effects of bufalin intervention on metabolite profile and metabolic pathway in LUAD nude mice were investigated by non-targeted metabolomics.

RESULTS

209 bufalin targets and 1082 LUAD-associated targets were harvested, of which 51 intersection targets were identified. 10 core targets including Akt1, STAT3, EGFR, CASP3 and SRC were picked out through network topology analysis, and they had a potent binding activity with bufalin as indicated by molecular docking and MD simulation. Hub module of PPI network was closely related to cell proliferation and apoptosis. GO and KEGG enrichment analyses suggested that bufalin exerted therapeutic effects on LUAD possibly by inhibiting proliferation and promoting apoptosis via PI3K/Akt, FoxO1 and MAPK/ERK pathways, which were confirmed by a series of in-vitro studies as well as HE, TUNEL and Ki-67 staining of tumor tissues. Further metabolomics analysis revealed that bufalin mainly regulated ABC transporter and remodeled AA metabolism, thereby contributing to the treatment of LUAD.

CONCLUSION

From molecular and metabolic perspective, the present study not only provided a unique insight into the possible mechanisms of bufalin against LUAD after successfully filtering out associated key target genes, differential endogenous metabolites, and signaling pathways, but also proposed a novel promising therapeutic strategy for LUAD.

Fucosyltransferases Regulated by Fusobacterium Nucleatum and Act as Novel Biomarkers in Colon Adenocarcinoma

Purpose

Colon adenocarcinoma (COAD) is one of the leading causes of cancer-associated mortality worldwide. Fucosyltransferases (FUTs) are associated with numerous cancers. We aimed to investigate the functions of FUTs in COAD.

Patients and Methods

Transcriptomic and clinical data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were used to analyze the expression and clinical relevance of FUTs in COAD. Real Time Quantitative PCR (RT-qPCR), Western blot, immunohistochemistry and ELISA were used to detect the relative RNA and protein expression levels. Colitis-associated cancer mice treated with Fusobacterium nucleatum were used to illustrate the effects of Fusobacterium nucleatum on FUTs and COAD. Luciferase reporting assay was used to investigate the binding of miRNA to mRNA.

Results

TCGA and GEO datasets showed abnormal expression of FUTs in COAD at transcript level. RT-qPCR, Western blot and immunohistochemistry showed increased expression of FUT1, POFUT1 and POFUT2 in COAD. COAD patients with a high expression of FUT1, FUT11, FUT13 (POFUT2) had a worse prognosis, while patients with a high expression of FUT2, FUT3, FUT6 had a better prognosis. FUT1 and POFUT2 could independently predict the prognosis of COAD patients. Functional analysis by CancerSEA database showed that FUT3, FUT6, FUT8, FUT12 (POFUT1) and FUT13 are associated with differentiation, apoptosis, invasion, quiescence, and hypoxia. FUTs are associated with the tumor microenvironment of COAD. FUT1 regulated by miR-939-3p inhibit the expression of MUC2. Fusobacterium nucleatum may affect the expression of FUTs by affecting their transcription factors and miRNA levels. Moreover, Fusobacterium nucleatum promotes COAD progression through the miR-939-3p/FUT1/MUC2 axis.

Conclusion

Fucosyltransferases play an important role and may be the mediator of Fusobacterium nucleatum promoting COAD progression.

Expression of GnT-III decreases chemoresistance via negatively regulating P-glycoprotein expression: Involvement of the TNFR2-NF-κB signaling pathway

The phenomenon of multidrug resistance (MDR) is called chemoresistance with respect to the treatment of cancer, and it continues to be a major challenge. The role of N-glycosylation in chemoresistance, however, remains poorly understood. Here, we established a traditional model for adriamycin resistance in K562 cells, which are also known as K562/adriamycin-resistant (ADR) cells. Lectin blot, mass spectrometry, and RT-PCR analysis showed that the expression levels of N-acetylglucosaminyltransferase III (GnT-III) mRNA and its products, bisected N-glycans, are significantly decreased in K562/ADR cells, compared with the levels in parent K562 cells. By contrast, the expression levels of both P-glycoprotein (P-gp) and its intracellular key regulator, NF-κB signaling, are significantly increased in K562/ADR cells. These upregulations were sufficiently suppressed by the overexpression of GnT-III in K562/ADR cells. We found that the expression of GnT-III consistently decreased chemoresistance for doxorubicin and dasatinib, as well as activation of the NF-κB pathway by tumor necrosis factor (TNF) α, which binds to two structurally distinct glycoproteins, TNF receptor 1 (TNFR1) and TNF receptor 2 (TNFR2), on the cell surface. Interestingly, our immunoprecipitation analysis revealed that only TNFR2, but not TNFR1, contains bisected N-glycans. The lack of GnT-III strongly induced TNFR2's autotrimerization without ligand stimulation, which was rescued by the overexpression of GnT-III in K562/ADR cells. Furthermore, the deficiency of TNFR2 suppressed P-gp expression while it increased GnT-III expression. Taken together, these results clearly show that GnT-III negatively regulates chemoresistance via the suppression of P-gp expression, which is regulated by the TNFR2-NF/κB signaling pathway.

FUT8 is regulated by miR-122-5p and promotes malignancies in intrahepatic cholangiocarcinoma via PI3K/AKT signaling

BACKGROUND

Intrahepatic cholangiocarcinoma (iCCA) is the second-most lethal primary liver cancer and its prognosis remains dismal. N-glycosylation, which is biosynthesized by a number of glycosyltransferases, plays an important role in a variety of biological processes and is associated with cancer development and progression.

METHODS

Based on our previous proteogenomic resources from an iCCA cohort of 262 patients, fucosyltransferases 8 (FUT8) showed significant prognosis relevance in iCCA. Tumor tissues from iCCA patients were used to evaluate the correlation between its expression and clinical information. Gain/loss-of-function experiments in iCCA cell lines were performed to elucidate the biological function of FUT8. In addition, its downstream pathways and post-transcriptional regulators were inferred and verified.

RESULTS

Elevated FUT8 expression was clinically associated with worse overall survival in iCCA patients. Its overexpression promoted migration, invasion and proliferation ability of iCCA cells. In addition, miR-122-5p was found to act as a post-transcriptional regulator of FUT8 and proved to inhibit FUT8 expression and then suppress the proliferation and migration ability of iCCA cell lines. Furthermore, FUT8 was observed to promote iCCA development through PI3K/AKT signaling pathway.

CONCLUSIONS

These findings demonstrated that FUT8, regulated by miR-122-5p, could be a tumor promoter of iCCA through PI3K/AKT signaling pathway.

Biological impact and therapeutic perspective of targeting PI3K/Akt signaling in hepatocellular carcinoma: Promises and Challenges

Cancer progression results from activation of various signaling networks. Among these, PI3K/Akt signaling contributes to proliferation, invasion, and inhibition of apoptosis. Hepatocellular carcinoma (HCC) is a primary liver cancer with high incidence rate, especially in regions with high prevalence of viral hepatitis infection. Autoimmune disorders, diabetes mellitus, obesity, alcohol consumption, and inflammation can also lead to initiation and development of HCC. The treatment of HCC depends on the identification of oncogenic factors that lead tumor cells to develop resistance to therapy. The present review article focuses on the role of PI3K/Akt signaling in HCC progression. Activation of PI3K/Akt signaling promotes glucose uptake, favors glycolysis and increases tumor cell proliferation. It inhibits both apoptosis and autophagy while promoting HCC cell survival. PI3K/Akt stimulates epithelial-to-mesenchymal transition (EMT) and increases matrix-metalloproteinase (MMP) expression during HCC metastasis. In addition to increasing colony formation capacity and facilitating the spread of tumor cells, PI3K/Akt signaling stimulates angiogenesis. Therefore, silencing PI3K/Akt signaling prevents aggressive HCC cell behavior. Activation of PI3K/Akt signaling can confer drug resistance, particularly to sorafenib, and decreases the radio-sensitivity of HCC cells. Anti-cancer agents, like phytochemicals and small molecules can suppress PI3K/Akt signaling by limiting HCC progression. Being upregulated in tumor tissues and clinical samples, PI3K/Akt can also be used as a biomarker to predict patients' response to therapy.

Cancer fitness genes: emerging therapeutic targets for metastasis

Development of cancer therapeutics has traditionally focused on targeting driver oncogenes. Such an approach is limited by toxicity to normal tissues and treatment resistance. A class of 'cancer fitness genes' with crucial roles in metastasis have been identified. Elevated or altered activities of these genes do not directly cause cancer; instead, they relieve the stresses that tumor cells encounter and help them adapt to a changing microenvironment, thus facilitating tumor progression and metastasis. Importantly, as normal cells do not experience high levels of stress under physiological conditions, targeting cancer fitness genes is less likely to cause toxicity to noncancerous tissues. Here, we summarize the key features and function of cancer fitness genes and discuss their therapeutic potential.

Novel blood-based FUT7 DNA methylation is associated with lung cancer: especially for lung squamous cell carcinoma

BACKGROUND

The death rate of lung cancer (LC) ranks first in the world. Changes of DNA methylation in peripheral blood may be related to malignant tumors. It is necessary to explore blood-based biomarkers of methylation to detect LC.

METHODS

Mass spectrometry assays were conducted to measure DNA methylation levels of seven CpG sites within FUT7 gene in the peripheral blood of 428 patients with LC, 233 patients with benign pulmonary nodule (BPN) and 862 normal controls (NC). The odds ratios (ORs) of all CpG sites were evaluated for their risk to LC using per SD change and tertiles analyses by logistic regression. The predictive ability of the seven FUT7 CpG sites and risk factors were evaluated by receiver operating characteristic curve (ROC).

RESULTS

The methylation levels of seven CpG sites of FUT7 in LC were significantly lower than that in NC (P < 0.05). The per SD decrement of methylation level in CpG_1-7 was significantly associated with 65%, 38%, 59%, 46%, 23%, 20% and 68% higher risk for LC versus NC, respectively, and the adjusted ORs (95% CI) were 2.92 (2.17-3.96), 1.76 (1.29-2.38), 2.83 (2.09-3.82), 3.00 (2.17-4.16), 1.81 (1.35-2.43), 1.48 (1.11-1.97) and 3.04 (2.23-4.16) for the lowest tertiles of methylation level in CpG_1-7 compared with the top tertiles, respectively. The area under the curve (AUC) of FUT7_CpG_1-7 was 0.659 (CI 0.626-0.693), 0.792 (CI 0.736-0.848) and 0.729 (CI 0.665-0.792) in distinguishing LC versus NC, LUSC versus NC and LUSC versus BPN.

CONCLUSIONS

Our study revealed an association between FUT7 hypomethylation and LC, especially for LUSC, which provides novel support for the blood-based methylation signatures as potential marker for assessing lung cancer risk.

Identification of a Novel Glycosyltransferase Prognostic Signature in Hepatocellular Carcinoma Based on LASSO Algorithm

Although many prognostic models have been developed to help determine personalized prognoses and treatments, the predictive efficiency of these prognostic models in hepatocellular carcinoma (HCC), which is a highly heterogeneous malignancy, is less than ideal. Recently, aberrant glycosylation has been demonstrated to universally participate in tumour initiation and progression, suggesting that dysregulation of glycosyltransferases can serve as novel cancer biomarkers. In this study, a total of 568 RNA-sequencing datasets of HCC from the TCGA database and ICGC database were analysed and integrated via bioinformatic methods. LASSO regression analysis was applied to construct a prognostic signature. Kaplan-Meier survival, ROC curve, nomogram, and univariate and multivariate Cox regression analyses were performed to assess the predictive efficiency of the prognostic signature. GSEA and the "CIBERSORT" R package were utilized to further discover the potential biological mechanism of the prognostic signature. Meanwhile, the differential expression of the prognostic signature was verified by western blot, qRT-PCR and immunohistochemical staining derived from the HPA. Ultimately, we constructed a prognostic signature in HCC based on a combination of six glycosyltransferases, whose prognostic value was evaluated and validated successfully in the testing cohort and the validation cohort. The prognostic signature was identified as an independent unfavourable prognostic factor for OS, and a nomogram including the risk score was established and showed the good performance in predicting OS. Further analysis of the underlying mechanism revealed that the prognostic signature may be potentially associated with metabolic disorders and tumour-infiltrating immune cells.

Sesquiterpene Lactones Attenuate Paclitaxel Resistance Via Inhibiting MALAT1/STAT3/ FUT4 Axis and P-Glycoprotein Transporters in Lung Cancer Cells

Paclitaxel resistance is a challenging factor in chemotherapy resulting in poor prognosis and cancer recurrence. Signal transducer and activator of transcription factor 3 (STAT3), a key transcription factor, performs a critical role in cancer development, cell survival and chemoresistance, while its inactivation overwhelms drug resistance in numerous cancer types including lung cancer. Additionally, the fucosyltransferase 4 (FUT4) is a crucial enzyme in post-translational modification of cell-surface proteins involved in various pathological conditions such as tumor multidrug resistance (MDR). The P-glycoprotein (P-GP) is the well-known ABC transporter member that imparts drug resistance in different cancer types, most notably paclitaxel resistance in lung cancer cells. LncRNA-MALAT1 exerts a functional role in the cancer development as well as the drug resistance and is linked with STAT3 activation and activity of FUT4. Moreover, STAT3-mediated induction of P-GP is well-documented. Natural compounds of Sesquiterpene Lactone (SL) family are well-known for their anticancer properties with particular emphasis over STAT3 inhibitory capabilities. In this study, we explored the positive correlation of MALAT1 with STAT3 and FUT4 activity in paclitaxel resistant A549 (A549/T) lung cancer cells. Additionally, we investigated the anticancer activity of two well-known members of SLs, alantolactone (ALT) and Brevilin A (Brv-A), in A549/T lung cancer cells. ALT and Brv-A induced apoptosis in A549/T cells. Furthermore, these two natural SLs suppressed MALAT1 expression, STAT3 activation, and FUT4 and P-GP expression which are the hallmarks for paclitaxel resistance in A549 lung cancer cells. The inhibition of MALAT1 enhanced the competence of these SLs members significantly, which accounted for the growth inhibition as well as anti-migratory and anti-invasive effects of ALT and Brv-A. These findings suggest SLs to be the promising agents for overcoming paclitaxel resistance in A549 lung cancer cells.

Surface glycan targeting for cancer nano-immunotherapy

Cancer immunotherapy is an emerging therapeutic strategy for cancer treatment. Most of the immunotherapeutics approved by the FDA regulate the innate immune system and associated immune cell activity, with immune check inhibitors in particular having transformed the field of cancer immunotherapy due to their significant clinical potential. However, previously reported immunotherapeutics have exhibited undesirable side effects, including autoimmune toxicity and inflammation. Controlling these deleterious responses and designing therapeutics that can precisely target specific regions are thus crucial to improving the efficacy of cancer immunotherapies. Recent studies have reported that cancer cells employ glycan-immune checkpoint interactions to modulate immune cell activity. Thus, the recognition of cancer glycan moieties such as sialoglycans may improve the anticancer activity of immune cells. In this review, we discuss recent advances in cancer immunotherapies involving glycans and glycan-targeting technologies based on nanomaterial-assisted local delivery systems.

Protein Core Fucosylation Regulates Planarian Head Regeneration via Neoblast Proliferation

Protein glycosylation is an important posttranslational modification that plays a crucial role in cellular function. However, its biological roles in tissue regeneration remain interesting and primarily ambiguous. In this study, we profiled protein glycosylation during head regeneration in planarian Dugesia japonica using a lectin microarray. We found that 6 kinds of lectins showed increased signals and 16 kinds showed decreased signals. Interestingly, we found that protein core fucosylation, manifested by Lens culinaris agglutinin (LCA) staining, was significantly upregulated during planarian head regeneration. Lectin histochemistry indicated that the LCA signal was intensified within the wound and blastemal areas. Furthermore, we found that treatment with a fucosylation inhibitor, 2F-peracetyl-fucose, significantly retarded planarian head regeneration, while supplement with L-fucose could improve DjFut8 expression and stimulate planarian head regeneration. In addition, 53 glycoproteins that bound to LCA were selectively isolated by LCA-magnetic particle conjugates and identified by LC-MS/MS, including the neoblast markers DjpiwiA, DjpiwiB, DjvlgA, and DjvlgB. Overall, our study provides direct evidence for the involvement of protein core fucosylation in planarian regeneration.

The Role of Glycosyltransferases in Colorectal Cancer

Colorectal cancer (CRC) is one of the main causes of cancer death in the world. Post-translational modifications (PTMs) have been extensively studied in malignancies due to its relevance in tumor pathogenesis and therapy. This review is focused on the dysregulation of glycosyltransferase expression in CRC and its impact in cell function and in several biological pathways associated with CRC pathogenesis, prognosis and therapeutic approaches. Glycan structures act as interface molecules between cells and their environment and in several cases facilitate molecule function. CRC tissue shows alterations in glycan structures decorating molecules, such as annexin-1, mucins, heat shock protein 90 (Hsp90), β1 integrin, carcinoembryonic antigen (CEA), epidermal growth factor receptor (EGFR), insulin-like growth factor-binding protein 3 (IGFBP3), transforming growth factor beta (TGF-β) receptors, Fas (CD95), PD-L1, decorin, sorbin and SH3 domain-containing protein 1 (SORBS1), CD147 and glycosphingolipids. All of these are described as key molecules in oncogenesis and metastasis. Therefore, glycosylation in CRC can affect cell migration, cell–cell adhesion, actin polymerization, mitosis, cell membrane repair, apoptosis, cell differentiation, stemness regulation, intestinal mucosal barrier integrity, immune system regulation, T cell polarization and gut microbiota composition; all such functions are associated with the prognosis and evolution of the disease. According to these findings, multiple strategies have been evaluated to alter oligosaccharide processing and to modify glycoconjugate structures in order to control CRC progression and prevent metastasis. Additionally, immunotherapy approaches have contemplated the use of neo-antigens, generated by altered glycosylation, as targets for tumor-specific T cells or engineered CAR (Chimeric antigen receptors) T cells.

Integrating transcriptomics, proteomics, glycomics and glycoproteomics to characterize paclitaxel resistance in breast cancer cells

Chemoresistance is a major factor driving breast cancer (BC) relapse and the high rates of cancer-related deaths. Aberrant levels of glycans are closely correlated with chemoresistance. The essential functions of glycans in chemoresistance is not systematically studied. In this study, an integrated strategy with a combination of transcriptomics, proteomics, glycomics and glycoproteomics was applied to explore the dysregulation of glycogenes, glycan structures and glycoproteins in chemoresistance of breast cancer cells. In paclitaxel (PTX) resistant MCF7 cells, 19 differentially expressed N-glycan-related proteins were identified, of which MGAT4A was the most significantly down-regulated, consistent with decrease in MGAT4A expression at mRNA level in PTX treated BC cells. Glycomic analysis consistently revealed suppressed levels of multi-antennary branching structures using MALDI-TOF/TOF-MS and lectin microarray. Several target glycoproteins bearing suppressed levels of multi-antennary branching structures were identified, and ERK signaling pathway was strongly suppressed in PTX resistant MCF7 cells. Our findings demonstrated the aberrant levels of multi-antennary branching structures and their target glycoproteins on PTX resistance. Systematically integrative multi-omic analysis is expected to facilitate the discovery of the aberrant glycosyltransferases, N-glycosylation and glycoproteins in tumor progression and chemoresistance. SIGNIFICANCE: An integrated strategy with a combination of transcriptomics, proteomics, glycomics and glycoproteomics is crucial to understand the association between glycans and chemoresistance in BC. In this multi-omic analysis, we identified unique glycan-related protein, glycan and glycoprotein signatures defining PTX chemoresistance in BC. This study might provide valuable information to understand molecular mechanisms underlying chemoresistance in BC.

FUT8 and Protein Core Fucosylation in Tumours: From Diagnosis to Treatment

Glycosylation changes are key molecular events in tumorigenesis, progression and glycosyltransferases play a vital role in the this process. FUT8 belongs to the fucosyltransferase family and is the key enzyme involved in N-glycan core fucosylation. FUT8 and/or core fucosylated proteins are frequently upregulated in liver, lung, colorectal, pancreas, prostate,breast, oral cavity, oesophagus, and thyroid tumours, diffuse large B-cell lymphoma, ependymoma, medulloblastoma and glioblastoma multiforme and downregulated in gastric cancer. They can be used as markers of cancer diagnosis, occurrence, progression and prognosis. Core fucosylated EGFR, TGFBR, E-cadherin, PD1/PD-L1 and α3β1 integrin are potential targets for tumour therapy. In addition, IGg1 antibody defucosylation can improve antibody affinity, which is another aspect of FUT8 that could be applied to tumour therapy.

Long noncoding RNA TUG1 regulates degradation of chondrocyte extracellular matrix via miR-320c/MMP-13 axis in osteoarthritis

Osteoarthritis (OA) is a common chronic joint disease. This study aimed to explore the function of long noncoding RNA taurine-upregulated gene 1 (TUG1) in the progression and initiation of OA. Levels of TUG1, microRNA-320c (miR-320c) and fucosyltransferase 4 (FUT4) were examined via quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide and flow cytometry assays were used to detect cell viability and apoptosis, respectively. The expression of relative proteins was measured using Western blot. The interaction between miR-320c and TUG1 or FUT4 was confirmed utilizing dual-luciferase reporter and RNA immunoprecipitation assays. In this study, levels of TUG1 and FUT4 were distinctly upregulated, but miR-320c level significantly decreased in OA tissues and chondrocytes derived from OA tissues as well as in IL-1β-stimulated C28/I2 cells. Mechanically, TUG1 sponged miR-320c and miR-320c targeted FUT4. In addition, TUG1 knockdown accelerated cell proliferation and repressed apoptosis and extracellular matrix (ECM) degradation in IL-1β-induced C28/I2 cells, whereas these effects of TUG1 deletion were rescued by either miR-320c inhibitor or FUT4 upregulation. Meanwhile, TUG1 sponged miR-320c to regulate FUT4 expression in IL-1β-induced C28/I2 cells. Collectively, TUG1 modulated cell proliferation, apoptosis and ECM degradation in IL-1β-induced C28/I2 cells via the miR-320c/FUT4 axis, providing a new insight into the OA treatment.

AFP-Inhibiting Fragments for Drug Delivery: The Promise and Challenges of Targeting Therapeutics to Cancers

Alpha fetoprotein (AFP) plays a key role in stimulating the growth, metastasis and drug resistance of hepatocellular carcinoma (HCC). AFP is an important target molecule in the treatment of HCC. The application of AFP-derived peptides, AFP fragments and recombinant AFP (AFP-inhibiting fragments, AIFs) to inhibit the binding of AFP to intracellular proteins or its receptors is the basis of a new strategy for the treatment of HCC and other cancers. In addition, AIFs can be combined with drugs and delivery agents to target treatments to cancer. AIFs conjugated to anticancer drugs not only destroy cancer cells with these drugs but also activate immune cells to kill cancer cells. Furthermore, AIF delivery of drugs relieves immunosuppression and enhances chemotherapy effects. The synergism of immunotherapy and targeted chemotherapy is expected to play an important role in enhancing the treatment effect of patients with cancer. AIF delivery of drugs will be an available strategy for the targeted treatment of cancer in the future.

FUT8 Remodeling of EGFR Regulates Epidermal Keratinocyte Proliferation during Psoriasis Development

α-(1,6)-fucosyltransferase 8 (FUT8) is implicated in the pathogenesis of several malignancies, but its role in psoriasis is poorly understood. In this study, we show that FUT8 remodeling of EGFR plays a critical role in the development of psoriasis phenotypes. Notably, elevated FUT8 expression was associated with disease severity in the lesional epidermis of a patient with psoriasis. FUT8 gain of function promoted HaCaT cell proliferation, whereas short hairpin FUT8 reduced cell proliferation and induced a longer S phase with downregulation of cyclin A1 expression. Furthermore, cell proliferation, which is controlled by the activation of EGFR, was shown to be regulated by FUT8 core fucosylation of EGFR. Short hairpin FUT8 significantly reduced EGFR/protein kinase B signaling and slowed EGF‒EGFR complex trafficking to the perinuclear region. Moreover, short hairpin FUT8 reduced ligand-induced EGFR dimerization. Overactivated EGFR was observed in the lesional epidermis of both human patient and psoriasis-like mouse model, whereas conditional knockout of FUT8 in an IL-23 psoriasis-like mouse model ameliorated disease phenotypes and reduced EGFR activation in the epidermis. These findings implied that elevated FUT8 expression in the lesional epidermis is implicated in the development of psoriasis phenotypes, being required for EGFR overactivation and leading to keratinocyte hyperproliferation.

MicroRNA-200b relieves LPS-induced inflammatory injury by targeting FUT4 in knee articular chondrocytes in vitro

Osteoarthritis (OA), characterized by the degeneration of articular cartilage, is a major problem in aging populations, and cartilage chondrocytes have been indicated to serve a curial role in the progression of OA. MicroRNA-200b-3p (miR-200b) was preliminarily identified to participate in OA. However, its role and mechanism of action in injured chondrocytes in OA remain unclear to date. In the present study, lipopolysaccharide (LPS)-treated cells isolated from normal knee articular cartilage were used to mimic inflammatory injury of OA chondrocytes. Cell viability, apoptosis and inflammatory responses were detected using Cell Counting Kit-8, flow cytometry and enzyme-linked immunosorbent assay, respectively. The expression levels of miR-200b and fucosyltransferase-4 (FUT4) were measured by reverse transcription-quantitative PCR and western blotting. The association between miR-200b and FUT4 was verified using TargetScan software, dual-luciferase reporter assay and RNA immunoprecipitation. The results indicated that LPS treatment decreased cell viability of primary chondrocytes, and increased apoptosis rate and production of IL-1β, IL-6 and TNF-α. The expression level of miR-200b was downregulated, and that of FUT4 was upregulated in OA cartilage tissues and LPS-treated normal chondrocytes compared with normal cartilage tissues and chondrocytes. Overexpression of miR-200b via transfection with miR-200b mimic inhibited the apoptosis rate and reduced the levels of IL-1β, IL-6 and TNF-α in LPS-stimulated chondrocytes. However, the suppressive effect of miR-200b overexpression on the LPS-induced inflammatory injury in chondrocytes was reversed by the restoration of FUT4 levels. Notably, FUT4 was indicated to be a downstream target of miR-200b and was negatively regulated by miR-200b. Taken together, the results of the current study indicated that miR-200b protected chondrocytes from LPS-induced inflammatory injury in vitro by targeting FUT4. These findings revealed the miR-200b/FUT4 axis as a potential candidate to target the degeneration of cartilages, thereby inhibiting the progression of OA.

Alterations of Fucosyltransferase Genes and Fucosylated Glycans in Gastric Epithelial Cells Infected with Helicobacter pylori

Helicobacter pylori (H. pylori) adhesion to human gastric epithelial cells is closely linked with fucosylated glycans. Therefore, investigation of fucosylation in the interaction of gastric epithelial cells with H. pylori is critical. In this study we used lectin microarrays to detect the expression of fucosylated glycans in gastric epithelial cells (GES-1) infected with H. pylori strains isolated from patients with different diseases including chronic gastritis, duodenal ulcers, and gastric cancer (each containing two strains) at 4 h. In addition, we investigated the time-course expression of fucosyltransferase (FUT) 1–6 genes in GES-1 cells stimulated with H. pylori strains at 0.5–8 h. At 4 h post-infection, Lotus, AAA, BC2LCN, PA-IIL, CNL and ACG lectins had increased signals in H. pylori-infected GES-1 cells compared to uninfected cells. Higher expression of FUT1 and FUT2 was detected in all H. pylori-infected GES-1 cells within 2 h, regardless of the H. pylori strain. In particular, the expression of FUT2 was higher in H. pylori-infected GES-1 cells with a higher fold change in levels of BC2LCN lectin specific to α1-2 linked fucose (Fuc) at 4 h. The results suggest that the high levels of α1, 2-linked Fuc synthesized by FUT1/2, might play a role in the preliminary stage of H. pylori infection. This provides us with pivotal information to understand the adhesion of H. pylori to human gastric epithelial cells.

Functional Interaction among lncRNA HOTAIR and MicroRNAs in Cancer and Other Human Diseases

Simple Summary

This review aimed to describe the contribution of functional interaction between the lncRNA HOTAIR and microRNAs in human diseases, including cancer. HOTAIR/miRNAs complexes interfere with different cellular processes during carcinogenesis, mainly deregulating a series of oncogenic signaling pathways. A great number of ncRNAs-related databases have been established, supported by bioinformatics technologies, to identify the ncRNA-mediated sponge regulatory network. These approaches need experimental validation through cells and animal models studies. The optimization of systems to interfere with HOTAIR/miRNAs interplay could represent a new tool for the definition of diagnostic therapeutics in cancer patients.

Abstract

LncRNAs are a class of non-coding RNAs mostly involved in regulation of cancer initiation, metastatic progression, and drug resistance, through participation in post-transcription regulatory processes by interacting with different miRNAs. LncRNAs are able to compete with endogenous RNAs by binding and sequestering miRNAs and thereby regulating the expression of their target genes, often represented by oncogenes. The lncRNA HOX transcript antisense RNA (HOTAIR) represents a diagnostic, prognostic, and predictive biomarker in many human cancers, and its functional interaction with miRNAs has been described as crucial in the modulation of different cellular processes during cancer development. The aim of this review is to highlight the relation between lncRNA HOTAIR and different microRNAs in human diseases, discussing the contribution of these functional interactions, especially in cancer development and progression.

Investigation of a new oxazolidine derivative in human resistance acute leukemia cells: deciphering its mechanism of action by label-free proteomic

The present study aimed to evaluate the mechanism of action of the antineoplastic activity of an oxazolidine derivative, LPSF/NB-3 (5-(4-cloro-benzilideno)-3-etil-2-tioxo-oxazolidin-4-ona). Cytotoxicity assays were performed in peripheral blood mononuclear cells (PBMCs) and resistant acute leukemia cell line (HL-60/MX1) by the MTT method. LPSF/NB-3 exhibited cytotoxicity in HL-60/MX1, but it was not toxic to healthy cells in the highest dose tested (100 μM). The protein extract of HL-60/MX1 cells treated with LPSF/NB-3 was subjected to proteomic analysis using two-dimensional chromatography coupled to mass spectrometry. We could identify a total of 2652 proteins, in which 633 were statistically modulated. Within the group of protein considered for the quantitative analysis with the established criteria, 262 were differentially expressed, 146 with increased expression and 116 with decreased expression in the sample treated with LPSF/NB-3 compared to the control. The following differentially expressed pathways were found: involving regulation of the cytoskeleton, DNA damage, and transduce cellular signals. Networks that were highlighted are related to the immune system. The ELISA technique was used to assess the immunomodulatory potential of LPSF/NB-3 in PBMCs. We observed significant decrease of IFNγ (p < 0.01) and dose-response pattern of the cytokines IL-6, IL-17A, IL-22, and IL-10. Therefore, results suggest that LPSF/NB-3 appears to modulate important pathways, including cell cycle and immune system regulatory pathways.

CircSND1 Regulated by TNF-α Promotes the Migration and Invasion of Cervical Cancer Cells

Aim

To explore the role and potential mechanism of circSND1 in cervical cancer (CC).

Main Methods

qRT-PCR was used to determine the expression of circSND1 in tumor necrosis factor-α (TNF-α)-treated HeLa cells. CircSND1 overexpression and knockdown were performed to indicate the functional role of circSND1 in vitro and in vivo. Luciferase assay was used to analyze promoter activity. The expression and regulation of circSND1, miR-125a-3p and FUT6 were evaluated using EGFP fluorescent reporter assay and rescue experiments. Immunofluorescence and Western blot assays were used to analyze the activation of nuclear factor-κB (NF-κB).

Results

In HeLa cells, TNF-α up-regulated the expression of circSND1 by activating the NF-κB signaling pathway. Overexpression of circSND1 significantly increased the migration and invasion and the epithelial–mesenchymal transition (EMT) process of CC cells, and promoted tumor metastasis in xenograft nude mouse model, whereas down-regulation of circSND1 exerted opposite effects. Furthermore, circSND1 enhanced the expression of FUT6 via sponging miR-125a-3p, and FUT6 activated NF-κB signaling pathway.

Conclusion

We found that circSND1 promoted the expression of FUT6 and the malignant behavior of cervical cancer through the ceRNA mechanism, and there was a TNF-α/NF-κB/circSND1/miR-125a-3p/FUT6/NF-κB positive feedback pathway between them, which suggests that circSND1 can be a promising prognostic marker and therapeutical target for cervical cancer.

CircularRNA circPARP4 promotes glioblastoma progression through sponging miR-125a-5p and regulating FUT4

Circular RNA (circRNA) is a widely expressed non-coding RNA element characterized by a covalently closed continuous loop. Emerging evidence suggests important roles of circRNAs in the pathogenesis of human cancers. However, the functions and underlying mechanisms of circRNAs in glioma remain largely unclear. Previously, our studies uncovered a batch of abnormally expressed circRNAs in glioma tissue, among which circPARP4 was significantly upregulated with the top fold change. Here, we focused on the functional investigation toward circPARP4 in glioblastoma progression and looked for insight into its underlying mechanisms. The results confirmed the elevated expression of circPARP4 in glioma and found its association with glioma pathological grade. Gain- and loss-of-function strategies showed that circPARP4 could obviously promote glioma cell proliferation, migration, invasion, and epithelial-mesenchymal transition. Mechanistically, in vivo and in vitro studies demonstrated that circPARP4, as a miRNA sponge, directly interacted with miR-125a-5p, which then regulated FUT4 to exert the oncogenic effect on glioma behavior. Our findings illustrate functions of circPARP4 in modulating glioma progression through miR-125a-5p/FUT4 pathway, which provides a novel and potential target for glioma therapy.

Dynamic Transcriptome Reveals the Mechanism of Liver Injury Caused by DHAV-3 Infection in Pekin Duck

Duck hepatitis A virus 3 (DHAV-3) is a wild endemic virus, which seriously endangers the duck industry in China. The present study aims to elucidate the mechanism of duck resistance to DHAV-3 infection. Both resistant and susceptible ducks were challenged with DHAV-3 in this experiment. The histopathological features and serum biochemical indices (ALT and AST) were analyzed to estimate liver injury status at 6, 12, 15, and 24 h post-infection (hpi). The dynamic transcriptomes of liver were analyzed to explain the molecular regulation mechanism in ducks against DHAV-3. The result showed that the liver injury in susceptible ducks was more serious than that in the resistant ducks throughout the four time points. A total of 2,127 differentially expressed genes (DEGs) were identified by comparing the transcriptome of the two populations. The expression levels of genes involved in innate immune response increased rapidly in susceptible ducks from 12 hpi. Similarly, the expression of genes involved in cytokine regulation also increased at the same time points, while the expression levels of these genes in resistant ducks remained similar between the various time points. KEGG enrichment analysis of the DEGs revealed that the genes involved in cytokine regulation and apoptosis were highly expressed in susceptible ducks than that in resistant ducks, suggesting that excessive cytokine storm and apoptosis may partially explain the mechanism of liver injury caused by DHAV-3 infection. Besides, we found that the FUT9 gene may contribute to resistance towards DHAV-3 in resistant ducklings. These findings will provide insight into duck resistance and susceptibility to DHAV-3 infection in the early phases, facilitate the development of a strategy for DHAV-3 prevention and treatment, and enhance genetic resistance via genetic selection in animal breeding.

Ginsenoside Rg3 enhances the anticancer effect of 5‑FU in colon cancer cells via the PI3K/AKT pathway

Chemotherapy is one of the most commonly used treatments for patients with advanced colon cancer, yet the toxicity of chemotherapy agents, such as 5‑fluorouracil (5‑FU), limits the effectiveness of chemotherapy. Ginsenoside Rg3 (Rg3) is an active ingredient isolated from ginseng. Rg3 has been shown to display anticancer effects on a variety of malignancies. Yet, whether Rg3 synergizes the effect of 5‑FU to inhibit the growth of human colon cancer remains unknown. The present study was designed to ascertain whether Rg3 is able to enhance the anti‑colon cancer effect of 5‑FU. The results revealed that combined treatment of Rg3 and 5‑FU significantly enhanced the inhibition of the proliferation, colony formation, invasion and migration of human colon cancer cells (SW620 and LOVO) in vitro. We also found that combined treatment of Rg3 and 5‑FU significantly enhanced the apoptosis of colon cancer cells by activating the Apaf1/caspase 9/caspase 3 pathway and arrested the cell cycle of the colon cancer cells in G0/G1 by promoting the expression of Cyclin D1, CDK2 and CDK4. In addition, the PI3K/AKT signaling pathway in colon cancer cells was suppressed by Rg3 and 5‑FU. In vivo, Rg3 synergized the effect of 5‑FU to inhibit the growth of human colon cancer xenografts in nude mice. Similarly, combined treatment of Rg3 and 5‑FU altered the expression of colon cancer protein in vivo and in vitro. Collectively, the present study demonstrated that ginsenoside Rg3 enhances the anticancer effect of 5‑FU in colon cancer cells via the PI3K/AKT pathway.

FUT4siRNA augments the chemosensitivity of non-small cell lung cancer to cisplatin through activation of FOXO1-induced apoptosis

Background

Increased fucosylation is associated with the chemoresistance phenotype. Meanwhile, fucosyltransferase IV (FUT4) amounts are frequently elevated in lung cancer and may be related to increased chemoresistance.

Methods

In the present work, FUT4’s role in cisplatin-induced apoptosis was assessed in A549 and H1975 cells, respectively. To clarify whether the FUT4 gene attenuates chemosensitivity in tumor cells, we constructed FUT4siRNA and evaluated its effects on cisplatin-induced apoptosis and cell growth inhibition. Cell viability, apoptosis, migration and invasion assay were conducted to investigate cisplatin sensitivity. The activation of EGFR/AKT/FOXO1 signaling were measured by western blot. The translocation of FOXO1 was assessed by IFC using Laser Scanning Confocal Microscope.

Results

We found that FUT4 knockdown dose-dependently increased cisplatin-associated cytotoxicity. Furthermore, FUT4 silencing induced apoptosis and inhibited proliferation in A549 and H1975 cells by suppressing Akt and FOXO1 phosphorylation induced by cisplatin administration, which resulted in nuclear translocation of FOXO1.

Conclusion

These results suggested FUT4 might control chemoresistance to cisplatin in lung cancer by suppressing FOXO1-induced apoptosis.

MALDI-2 Mass Spectrometry and Immunohistochemistry Imaging of Gb3Cer, Gb4Cer, and Further Glycosphingolipids in Human Colorectal Cancer Tissue

The main cellular receptors of Shiga toxins (Stxs), the neutral glycosphingolipids (GSLs), globotriaosylceramide (Gb3Cer/CD77) and globotetraosylceramide (Gb4Cer), are significantly upregulated in about half of the human colorectal carcinomas (CRC) and in other cancers. Therefore, conjugates exploiting the Gb3Cer/Gb4Cer-binding B subunit of Stx (StxB) have attracted great interest for both diagnostic and adjuvant therapeutic interventions. Moreover, fucosylated GSLs were recognized as potential tumor-associated targets. One obstacle to a broader use of these receptor/ligand systems is that the contribution of specific GSLs to tumorigenesis, in particular, in the context of an altered lipid metabolism, is only poorly understood. A second is that also nondiseased organs (e.g., kidney) and blood vessels can express high levels of certain GSLs, not least Gb3Cer/Gb4Cer. Here, we used, in a proof-of-concept study, matrix-assisted laser desorption/ionization mass spectrometry imaging combined with laser-induced postionization (MALDI-2-MSI) to simultaneously visualize the distribution of several Gb3Cer/Gb4Cer lipoforms and those of related GSLs (e.g., Gb3Cer/Gb4Cer precursors and fucosylated GSLs) in tissue biopsies from three CRC patients. Using MALDI-2 and StxB-based immunofluorescence microscopy, Gb3Cer and Gb4Cer were mainly found in dedifferentiated tumor cell areas, tumor stroma, and tumor-infiltrating blood vessels. Notably, fucosylated GSL such as Fuc-(n)Lc4Cer generally showed a highly localized expression in dysplastic glands and indian file-like cells infiltrating adipose tissue. Our "molecular histology" approach could support stratifying patients for intratumoral GSL expression to identify an optimal therapeutic strategy. The improved chemical coverage by MALDI-2 can also help to improve our understanding of the molecular basis of tumor development and GSL metabolism.

Use of the serum glycan state to predict ovarian cancer patients' clinical response to chemotherapy treatment

Ovarian cancer is the most lethal gynecologic carcinoma; because the tumor often relapses shortly after treatment. Glycosylation plays important roles in cancer drug resistance and could be used as biomarkers to predict the drug response of patients. We used MALDI-QIT-TOF MS to analyze the serum glycomic from patients with different drug responses. Samples were collected before treatment; follow-up visit were performed after 6 months. Forty-eight drug-sensitive patients and 16 drug-resistant patients were enrolled. Compared with drug-sensitive patients, 5 glyco-subclasses and 5 single glycans were significantly altered in drug-resistant patients. Lewis type, α2,3 sialic acid and multibranch glycans were increased, α2,6 sialic acid glycans were decreased. The peak at m/z 2986.44 showed stronger prediction abilities than other single glycans, with an AUC of 0.83. A panel of three increased glycans (m/z 2401.36, H5N4F1S2, a Lewis type biantennary glycan; m/z 2986.44, H6N5S3, a triantennary trisialylated glycan; m/z 3086.39, H6N5F1S3, a Lewis type triantennary glycan) combined with CA125 achieved an AUC value of 0.88, showing a strong discrimination performance. This study provides new insights into N-glycosylation patterns in ovarian cancer patients with different drug response. These altered glycans might serve as biomarkers to reflect patients' drug sensitivity and to guide clinical treatment. SIGNIFICANCE: A large number of ovarian cancer patients experience tumor relapse shortly after initial treatment. Glycosylation plays important roles in cancer drug resistance and could be used as a biomarker to predict the drug response of patients. However, the glycosylation expressed in patients with different drug response have not been elucidated. In the present study, we used MALDI-QIT-TOF MS to analyze the serum glycomic levels of patients with different drug responses. Several glycans were changed significantly between these two groups. A panel of three increased glycans (m/z 2401.36, a Lewis type biantennary glycan, 2986.44, a triantennary trisialylated glycan, and 3086.39, a Lewis type triantennary glycan) combined with CA125 performed better descrimination of these two groups with AUC of 0.88. These altered glycans might serve as biomarkers to reflect patients' drug sensitivity and to guide clinical treatment.

Dynamic analysis of N-glycomic and transcriptomic changes in the development of ovarian cancer cell line A2780 to its three cisplatin-resistant variants

Background

Platinum resistance development is a dynamic process that occurs during continuous chemotherapy and contributes to high mortality in ovarian cancer. Abnormal glycosylation has been reported in platinum resistance. Many studies on platinum resistance have been performed, but few of them have investigated platinum resistance-associated glycans based on N-glycomics. Moreover, glycomic alterations during platinum resistance development in ovarian cancer are rarely reported. Therefore, the objective of this study was to determine platinum resistance-related N-glycans in ovarian cancer cells during continuous exposure to cisplatin. These glycans might be involved in the mechanism of platinum resistance and serve as biomarkers to monitor its development.

Methods

This study mimicked the development of platinum resistance in ovarian cancer by continuously exposing A2780 cells to cisplatin. Cisplatin-resistant variants were confirmed by higher half maximal inhibitory concentration (IC₅₀) values and increased P-glycoprotein (ABCB1, P-gp) expression compared to A2780 cells. Analysis of dynamic N-glycomic changes during the development of platinum resistance in cisplatin-resistant variants was performed with MALDI-time-of-flight (TOF)-MS combined with ethyl esterification derivatization, which were used to discriminate between α2,3- and α2,6-linkage N-acetylneuraminic acid. N-glycan alterations were further validated on a glycotransferase level via transcriptome sequencing and real-time PCR (RT-PCR).

Results

Compared to the A2780 cells, MS analysis indicated that α2,3-linked sialic structures and N-glycan gal-ratios were significantly higher, while fucosylated glycans were lower in three cisplatin-resistant variants. Transcriptome sequencing and RT-PCR showed that gene expression of ST3GAL6 and MGAT4A increased, while gene expression of FUT11, FUT1, GMDS, and B4GALT5 decreased in three cisplatin-resistant variants.

Conclusions

Analysis of N-glycans and glycogene expression showed that α2,3-linked sialic structures might serve as biomarkers to monitor the development of platinum resistance and to guide individualized treatment of ovarian cancer patients.

α1,6-Fucosyltransferase (FUT8) regulates the cancer-promoting capacity of cancer-associated fibroblasts (CAFs) by modifying EGFR core fucosylation (CF) in non-small cell lung cancer (NSCLC)

Cancer-associated fibroblasts (CAFs) are the main cancer-promoting component in the tumor microenvironment (TME) of non-small cell lung cancer (NSCLC). α1,6-Fucosyltransferase (FUT8), the key enzyme catalyzing core α1,6-fucosylation (CF), plays a promoting role in multiple malignancies. In the current study, we investigated the function of FUT8 in CAFs and elucidated the mechanism through which FUT8 regulates the cancer-promoting capacity of CAFs in NSCLC. A bioinformatics analysis was performed to reveal the relationship between FUT8 and CAFs. Resected specimens from NSCLC patients were analyzed to assess the expression of FUT8 in CAFs. Primary CAFs and normal lung fibroblasts (NLFs) were extracted from NSCLC patient specimens and were co-cultured with NSCLC cell lines in a novel 3D-printed non-contact co-culture device. An In vivo CAF/NSCLC co-injection tumorigenesis assay was performed using nude mice to study the function of FUT8/CF in TME formation. The current study revealed that FUT8-mediated CF in CAFs plays a positive role in the cancer-promoting capacity of these cells. FUT8 overexpression was observed in CAFs isolated from some lung adenocarcinoma cases. Further investigation showed that FUT8/CF in CAFs promoted the formation of an invasive and malignant TME in vivo and in vitro, and the resulting NSCLC cells exhibited faster proliferation and increased invasiveness. EGFR signaling exerts a catalytic effect on the cancer-promoting capacity of CAFs and is regulated by the CF modification of the EGFR protein.

Proteomic Analysis Reveals that EPHX1 Contributes to 5-Fluorouracil Resistance in a Human Hepatocellular Carcinoma Cell Line

PURPOSE

The extensive drug resistance of hepatocellular carcinoma (HCC) has become a major cause of chemotherapy failure. A deeper understanding of the drug resistance mechanism of tumor cells is very significant for improving the clinical prognosis of patients with HCC.

EXPERIMENTAL DESIGN

In this study, proteomic studies on the composition of 5-fluorouracil (5-Fu) resistant Bel/5Fu cell line and its parent Bel7402 cell line by using an ionic liquid assisted proteins extraction method with the advantage of extracting plasma membrane proteins to a wider extent are performed. Then the expression level and function of differentially expressed plasma membrane proteins are verified.

RESULTS

In total, 25 plasma membrane proteins are shown differentially expressed in Bel/5Fu compared with Bel7402. Western blot analysis results further confirmed that the EPHX1 PLIN2 RAB27B SLC4A2 are upregulated in Bel/5Fu cells in accordance with the proteomics data. Moreover, cell viability assay and clonogenic survival assay results demonstrated that EPHX1 is closely related to the chemoresistance of Bel/5Fu to 5-Fu.

CONCLUSIONS AND CLINICAL RELEVANCE

Plasma membrane protein EPHX1 is closely related to the chemotherapy resistance of Bel/5Fu cells and can be used as a new drug target to improve the clinical prognosis of patients with HCC.

TPGS-1000 exhibits potent anticancer activity for hepatocellular carcinoma in vitro and in vivo

D-alpha-tocopheryl polyethylene glycol 1000 succinate (TPGS1000) is the most active water-soluble derivative of vitamin E and has been widely used as a carrier of solvents, plasticizers, emulsifiers, absorbent agents and refractory drug delivery systems. However, its anti-hepatocellular carcinoma (HCC) properties have not been explored. HCC cells were treated with different concentrations of TPGS1000. Cell survival was tested by CCK8 assay, and cell migration was tested by wound healing and Transwell assay. EdU staining verified cell proliferation, and signalling pathway was assayed by Western blot analysis. The BALB/c-nu mouse xenograft model was established to test HCC cell growth in vivo. In vitro TPGS1000 significantly inhibited the viability and mobility of HCC cells (HepG2, Hep3B and Huh7) in a dose-dependent manner. Cell cycle analysis indicated that TPGS1000 treatment arrested the HCC cell cycle in the G0/G1 phase, and induction of cell apoptosis was confirmed by TUNEL and Annexin V-7-AAD staining. Further pharmacological analysis indicated that collapse of the transmembrane potential of mitochondria, increased ROS generation, PARP-induced cell apoptosis and FoxM1-p21-mediated cell cycle arresting, were involved in the anti-HCC activity of TPGS1000. Moreover, treatment in vivo with TPGS1000 effectively impaired the growth of HCC xenografts in nude mice.

Role of fucosyltransferase IV in the migration and invasion of human melanoma cells

Malignant melanoma is one of the most aggressive human tumor types, mainly due to its high invasion capability, metastatic properties, and the absence of effective treatments. Glycosylation serves a pivotal role in the migration and invasion of melanoma. However, differences in glycosylation between high and low metastatic melanoma cells and how these regulate migration and invasion by altering the expression of fucosyltransferases (FUTs) remain unclear. In the present study, matrix-assisted laser desorption/ionization-time-of-flight-mass spectrometry (MALDI-TOF-MS) analysis revealed that the composition profiling of fucosylated N-glycans differed between high metastatic C8161 and low metastatic A375P cells. Further analysis revealed that FUT4 expression was significantly increased in C8161 cells. Melanoma tissue arrays further demonstrated that FUT4 was overexpressed in metastatic samples. Altered FUT4 expression was accompanied by a change in the migration and invasion capacity of the cells. In addition, the migration and invasion potential of melanoma cells were decreased in C8161 and increased in A375P cells upon altering FUT4 expression levels by small interfering RNA or complementary DNA transfection. Furthermore, regulating FUT4 expression markedly modulated the activity of the phosphoinositide-3-kinase/Akt (PI3K/Akt) signaling pathway, which affected melanoma cell migration and invasion. In conclusion, FUT4 is a novel biomarker and regulator of the migration and invasion of melanoma cells and may serve as a therapeutic target for melanoma.

The Diverse Contributions of Fucose Linkages in Cancer

Fucosylation is a post-translational modification of glycans, proteins, and lipids that is responsible for many biological processes. Fucose conjugation via α(1,2), α(1,3), α(1,4), α(1,6), and O'- linkages to glycans, and variations in fucosylation linkages, has important implications for cancer biology. This review focuses on the roles that fucosylation plays in cancer, specifically through modulation of cell surface proteins and signaling pathways. How L-fucose and serum fucosylation patterns might be used for future clinical diagnostic, prognostic, and therapeutic approaches will be discussed.

Long non-coding RNA HOTAIR/microRNA-206 sponge regulates STC2 and further influences cell biological functions in head and neck squamous cell carcinoma

Objective

It is essential to characterize underlying molecular mechanism associated with head and neck squamous cell carcinoma (HNSCC) and identify promising therapeutic targets. Herein, we explored role of homeobox transcript antisense RNA (HOTAIR) in HNSCC to regulate stanniocalcin‐2 (STC2) by sponging microRNA‐206 (miR‐206).

Methods

HNSCC‐related differentially expressed genes and regulation network amongst HOTAIR, miR‐206 and STC2 were identified. Next, effect of HOTAIR on cell biological functions of HNSCC was identified after transfection of cells with HOTAIR overexpressed plasmids or siRNA against HOTAIR. PI3K/AKT signalling pathway‐related gene expression was measured after miR‐206 and STC2 were suppressed. Cell invasion, migration and proliferation were assessed. Finally, tumour growth was assessed to determine the effects of HOTAIR/miR‐206/STC2 axis in vivo.

Results

HOTAIR specifically bound to miR‐206 and miR‐206 targeted STC2. Downregulated HOTAIR or upregulated miR‐206 suppressed HNSCC cell proliferation, invasion and migration. miR‐206 inhibited PI3K/AKT signalling pathway by down‐regulating STC2. Besides, silenced HOTAIR or overexpressed miR‐206 repressed the tumour growth of nude mice with HNSCC.

Conclusion

HOTAIR regulated HNSCC cell biological functions by binding to miR‐206 through STC2.

Expression of genes that control core fucosylation in hepatocellular carcinoma: Systematic review

BACKGROUND

Changes in N-linked glycosylation have been observed in the circulation of individuals with hepatocellular carcinoma. In particular, an elevation in the level of core fucosylation has been observed. However, the mechanisms through which core fucose is increased are not well understood. We hypothesized that a review of the literature and related bioinformatic review regarding six genes known to be involved in the attachment of core fucosylation, the synthesis of the fucosylation substrate guanosine diphosphate (GDP)-fucose, or the transport of the substrate into the Golgi might offer mechanistic insight into the regulation of core fucose levels.

AIM

To survey the literature to capture the involvement of genes regulating core N-linked fucosylation in hepatocellular carcinoma

METHODS

The PubMed biomedical literature database was searched for the association of hepatocellular carcinoma and each of the core fucose-related genes and their protein products. We also queried The Cancer Genome Atlas Liver hepatocellular carcinoma (LIHC) dataset for genetic, epigenetic and gene expression changes for the set of six genes using the tools at cBioportal.

RESULTS

A total of 27 citations involving one or more of the core fucosylation-related genes (FPGT, FUK, FUT8, GMDS, SLC35C1, TSTA3) and hepatocellular carcinoma were identified. The same set of gene symbols was used to query the 371 patients with liver cancer in the LIHC dataset to identify the frequency of mRNA over or under expression, as well as non-synonymous mutations, copy number variation and methylation level. Although all six genes trended to more samples displaying over expression relative to under-expression, it was noted that a number of tumor samples had undergone amplification of the genes of the de novo synthesis pathway, GMDS (27 samples) and TSTA3 (78 samples). In contrast, the other four genes had undergone amplification in 2 or fewer samples.

CONCLUSION

Amplification of genes involved in the de novo pathway for generation of GDP-fucose, GMDS and TSTA3, likely contributes to the elevated core fucose observed in hepatocellular carcinoma.

Prognostic value of the FUT family in acute myeloid leukemia

Genetic abnormalities are more frequently viewed as prognostic markers in acute myeloid leukemia (AML) in recent years. Fucosylation, catalyzed by fucosyltransferases (FUTs), is a post-translational modification that widely exists in cancer cells. However, the expression and clinical implication of the FUT family (FUT1-11) in AML has not been investigated. From the Cancer Genome Atlas database, a total of 155 AML patients with complete clinical characteristics and FUT1-11 expression data were included in our study. In patients who received chemotherapy alone showed that high expression levels of FUT3, FUT6, and FUT7 had adverse effects on event-free survival (EFS) and overall survival (OS) (all P < 0.05), whereas high FUT4 expression had favorable effects on EFS and OS (all P < 0.01). However, in the allogeneic hematopoietic stem cell transplantation (allo-HSCT) group, we only found a significant difference in EFS between the high and low FUT3 expression subgroups (P = 0.047), while other FUT members had no effect on survival. Multivariate analysis confirmed that high FUT4 expression was an independent favorable prognostic factor for both EFS (HR = 0.423, P = 0.001) and OS (HR = 0.398, P < 0.001), whereas high FUT6 expression was an independent risk factor for both EFS (HR = 1.871, P = 0.017) and OS (HR = 1.729, P = 0.028) in patients who received chemotherapy alone. Moreover, we found that patients with low FUT4 and high FUT6 expressions had the shortest EFS and OS (P < 0.05). Our study suggests that high expressions of FUT3/6/7 predict poor prognosis, high FUT4 expression indicates good prognosis in AML; FUT6 and FUT4 have the best prognosticating profile among them, but their effects could be neutralized by allo-HSCT.