Fucosylation is associated with the malignant transformation of intraductal papillary mucinous neoplasms: a lectin microarray-based study

Systematic review of challenging issues in pathology of intraductal papillary mucinous neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are a cystic precursor to pancreatic cancer. IPMNs deemed clinically to be at high-risk for malignant progression are frequently treated with surgical resection, and pathological examination of the pancreatectomy specimen is a key component of the clinical care of IPMN patients.

METHODS

Systematic literature reviews were conducted around eight topics of clinical relevance in the examination of pathological specimens in patients undergoing resection of IPMN.

RESULTS

This review provides updated perspectives on morphological subtyping of IPMNs, classification of intraductal oncocytic papillary neoplasms, nomenclature for high-grade dysplasia, assessment of T stage, distinction of carcinoma associated or concomitant with IPMN, role of molecular assessment of IPMN tissue, role of intraoperative assessment by frozen section, and preoperative evaluation of cyst fluid cytology.

CONCLUSIONS

This analysis provides the foundation for data-driven approaches to several challenging issues in the pathology of IPMNs.

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.

Beyond glyco-proteomics-Understanding the role of genetics in cancer biomarkers

The development of robust cancer biomarkers is the most effective way to improve overall survival, as early detection and treatment leads to significantly better clinical outcomes. Many of the cancer biomarkers that have been identified and are clinically utilized are glycoproteins, oftentimes a specific glycoform. Aberrant glycosylation is a common theme in cancer, with dysregulated glycosylation driving tumor initiation and metastasis, and abnormal glycosylation can be detection both on the tissue surface and in serum. However, most cancer types are heterogeneous in regard to tumor genomics, and this heterogeneity extends to cancer glycomics. This limits the sensitivity of standalone glycan-based biomarkers, which has slowed their implementation clinically. However, if targeted biomarker development can take into account genomic tumor information, the development of complementary biomarkers that target unique cancer subgroups can be accomplished. This idea suggests the need for algorithm-based cancer biomarkers, which can utilize multiple biomarkers along with relevant demographic information. This concept has already been established in the detection of hepatocellular carcinoma with the GALAD score, and an algorithm-based approach would likely be effective in improving biomarker sensitivity for additional cancer types. In order to increase cancer diagnostic biomarker sensitivity, there must be more targeted biomarker development that considers tumor genomic, proteomic, metabolomic, and clinical data while identifying tumor biomarkers.

Clinical and Molecular Attributes and Evaluation of Pancreatic Cystic Neoplasm

Intraductal papillary mucinous neoplasms (IPMNs) and mucinous cystic neoplasms (MCNs) are all considered "Pancreatic cystic neoplasms (PCNs)" and show a varying risk of developing into pancreatic ductal adenocarcinoma (PDAC). These lesions display different molecular characteristics, mutations, and clinical manifestations. A lack of detailed understanding of PCN subtype characteristics and their molecular mechanisms limits the development of efficient diagnostic tools and therapeutic strategies for these lesions. Proper in vivo mouse models that mimic human PCNs are also needed to study the molecular mechanisms and for therapeutic testing. A comprehensive understanding of the current status of PCN biology, mechanisms, current diagnostic methods, and therapies will help in the early detection and proper management of patients with these lesions and PDAC. This review aims to describe all these aspects of PCNs, specifically IPMNs, by describing the future perspectives.

α1,6-Fucosyltransferase contributes to cell migration and proliferation as well as to cancer stemness features in pancreatic carcinoma

BACKGROUND

Pancreatic carcinoma is one of the deadliest malignant diseases, in which the increased expression of α1,6-fucosyltransferase (FUT8), a sole enzyme responsible for catalyzing core fucosylation, has been reported. However, its pathological roles and regulatory mechanisms remain largely unknown. Here, we use two pancreatic adenocarcinoma cell lines, MIA PaCa-2 and PANC-1 cells, as cell models, to explore the relationship of FUT8 with the malignant transformation of PDAC.

METHODS

FUT8 knockout (FUT8-KO) cells were established by the CRISPR/Cas9 system. Cell migration was analyzed by transwell and wound-healing assays. Cell proliferation was examined by MTT and colony-formation assays. Cancer stemness markers and spheroid formations were used to analyzed cancer stemness features.

RESULTS

Deficiency of FUT8 inhibited cell migration and proliferation in both MIA PaCa-2 and PANC-1 cells compared with wild-type cells. Moreover, the expression levels of cancer stemness markers such as EpCAM, CXCR4, c-Met, and CD133 were decreased in the FUT8-KO cells compared with wild-type cells. Also, the spheroid formations in the KO cells were loose and unstable, which could be reversed by restoration with FUT8 gene in the KO cells. Additionally, FUT8-KO increased the chemosensitivity to gemcitabine, which is the first-line therapy for advanced pancreatic cancer.

CONCLUSIONS

FUT8-KO reduced the cell proliferation and migration. Our results are the first to suggest that the expression of FUT8 is involved in regulating the stemness features of pancreatic cancer cells.

GENERAL SIGNIFICANCE

FUT8 could provide novel insights for the treatment of pancreatic carcinoma.

FUT8 Alpha-(1,6)-Fucosyltransferase in Cancer

Aberrant glycosylation is a universal feature of cancer cells that can impact all steps in tumour progression from malignant transformation to metastasis and immune evasion. One key change in tumour glycosylation is altered core fucosylation. Core fucosylation is driven by fucosyltransferase 8 (FUT8), which catalyses the addition of α1,6-fucose to the innermost GlcNAc residue of N-glycans. FUT8 is frequently upregulated in cancer, and plays a critical role in immune evasion, antibody-dependent cellular cytotoxicity (ADCC), and the regulation of TGF-β, EGF, α3β1 integrin and E-Cadherin. Here, we summarise the role of FUT8 in various cancers (including lung, liver, colorectal, ovarian, prostate, breast, melanoma, thyroid, and pancreatic), discuss the potential mechanisms involved, and outline opportunities to exploit FUT8 as a critical factor in cancer therapeutics in the future.

Altered glycosylation associated with dedifferentiation of hepatocellular carcinoma: a lectin microarray-based study

Background

Altered glycosylation associated with hepatocellular carcinoma (HCC) is well documented. However, few reports have investigated the association between dedifferentiation and glycosylation. Therefore, the aim of this study was to analyze glycosylation associated with dedifferentiation of HCC within the same nodule and to investigate glycosyltransferase related to the glycosylation.

Methods

We analyzed resected HCC specimens (n = 50) using lectin microarray to comprehensively and sensitively analyze glycan profiles, and identify changes to glycosylation between well- and moderately-differentiated components within the same nodule. Moreover, we performed immunohistochemical staining of mannosyl(α-1,3-)-glycoprotein β-1,2-N-acetylglucosaminyltransferase (MGAT1), which is an essential glycosyltransferase that converts high-mannose glycans to complex- or hybrid-type N-glycans.

Results

Four lectins from Narcissus pseudonarcissus agglutinin (NPA), Concanavalin A, Galanthus nivalis agglutinin, and Calystegia sepium agglutinin were significantly elevated in moderately-differentiated components of HCC compared with well-differentiated components, and all lectins showed binding specificity to high-mannose glycans. Therefore, these structures were represented to a greater extent in moderately-differentiated components than in well-differentiated ones. Immunohistochemical staining revealed significantly increased NPA expression and decreased MGAT1 expression in moderately-differentiated components. Low MGAT1 expression in moderately-differentiated components of tumors was associated with intrahepatic metastasis and had tendency for poor prognosis.

Conclusion

Dedifferentiation of well-differentiated HCC is associated with an increase in high-mannose glycans. MGAT1 may play a role in the dedifferentiation of HCC.

Fucosyltransferase 8 plays a crucial role in the invasion and metastasis of pancreatic ductal adenocarcinoma

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer. It is an aggressive malignancy associated with poor prognosis because of recurrence, metastasis, and treatment resistance. Aberrant glycosylation of cancer cells triggers their migration and invasion and is considered one of the most important prognostic cancer biomarkers. The current study aimed to identify glycan alterations and their relationship with the malignant potential of PDAC.

METHODS

Using a lectin microarray, we evaluated glycan expression in 62 PDAC samples. Expression of fucosyltransferase 8 (FUT8), the only enzyme catalyzing core fucosylation, was investigated by immunohistochemistry. The role of FUT8 in PDAC invasion and metastasis was confirmed using an in vitro assay and a xenograft peritoneal metastasis mouse model.

RESULTS

The microarray data demonstrated that core fucose-binding lectins were significantly higher in carcinoma than in normal pancreatic duct tissues. Similarly, FUT8 protein expression was significantly higher in carcinoma than in normal pancreatic duct tissues. High FUT8 protein expression was significantly associated with lymph-node metastases and relapse-free survival. FUT8 knockdown significantly reduced the invasion in PDAC cell lines and impaired peritoneal metastasis in the xenograft model.

CONCLUSIONS

The findings of this study provide evidence that FUT8 plays a pivotal role in PDAC invasion and metastasis and might be a therapeutic target for this disease.

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.

Fucosyltransferase 2 induced epithelial-mesenchymal transition via TGF-β/Smad signaling pathway in lung adenocarcinaoma

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, TβRII, 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-β 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-β/Smad signaling. Overall, the current results indicated that FUT2 might promote LUAD metastasis through the EMT initiated by TGF-β/Smad signaling. Therefore, FUT2 might be a prognostic factor and therapeutic target for LUAD.

Glycomic Profiling Highlights Increased Fucosylation in Pseudomyxoma Peritonei

Pseudomyxoma peritonei (PMP) is a subtype of mucinous adenocarcinoma that most often originates from the appendix, and grows in the peritoneal cavity filling it with mucinous ascites. KRAS and GNAS mutations are frequently found in PMP, but other common driver mutations are infrequent. As altered glycosylation can promote carcinogenesis, we compared N-linked glycan profiles of PMP tissues to those of normal appendix. Glycan profiles of eight normal appendix samples and eight low-grade and eight high-grade PMP specimens were analyzed by mass spectrometry. Our results show differences in glycan profiles between PMP and the controls, especially in those of neutral glycans, and the most prominent alteration was increased fucosylation. We further demonstrate up-regulated mRNA expression of four fucosylation-related enzymes, the core fucosylation performing fucosyltransferase 8 and three GDP-fucose biosynthetic enzymes in PMP tissues when compared with the controls. Up-regulated protein expression of the latter three enzymes was further observed in PMP cells by immunohistochemistry. We also demonstrate that restoration of fucosylation either by salvage pathway or by introduction of an expression of intact GDP-mannose 4,6-dehydratase enhance expression of MUC2, which is the predominant mucin molecule secreted by the PMP cells, in an intestinal-derived adenocarcinoma cell line with defective fucosylation because of deletion in the GDP-mannose 4,6-dehydratase gene. Thus, altered glycosylation especially in the form of fucosylation is linked to the characteristic mucin production of PMP. Glycomic data are available via ProteomeXchange with identifier PXD010086.

Clinicopathological and prognostic significance of MUC13 and AGR2 expression in intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a primary pancreatic ductal epithelial neoplasm with the potential to develop into an invasive adenocarcinoma. This study aimed to investigate the clinicopathologic and prognostic significance of four potential biomarkers for the preoperative evaluation of patients with IPMN.

MATERIALS AND METHODS

Clinicopathologic materials from 104 patients with IPMN who underwent surgical resection at Jichi Medical University Hospital were analyzed. IPMNs (110 lesions in total) were histologically classified into low-grade IPMN (Group 1; n = 68), high-grade IPMN (Group 2; n = 16), or IPMN with an associated invasive carcinoma (Group 3; n = 26). We evaluated the immunohistochemical expression of MUC13, AGR2, FUT8, and FXYD3, which were previously reported to be overexpressed in pancreatic ductal adenocarcinoma.

RESULTS

The expression of MUC13 was more common in Group 3 compared with groups 1 and 2 (p < 0.001) and was associated with poor prognosis (p = 0.004). The expression of MUC13 was not associated with age, sex, tumor location, histological subtype, lymphatic or vascular invasion, or neural invasion. In most cases of IPMN, the loss of expression of AGR2 appeared to show an association with tumor recurrence and poorly differentiated histology of invasive carcinoma; however, this association was not statistically significant. The expressions of FUT8 and FXYD3were not associated with the clinicopathological features of IPMNs.

CONCLUSIONS

The results suggest that MUC13 overexpression and loss of expression of AGR2 may predict the progression of IPMN and an unfavorable prognosis in patients with IPMN.

Clinical significance and biological function of fucosyltransferase 2 in lung adenocarcinoma

Fucosylation, which is catalyzed by fucosyltransferases (FUTs), is one of the most important glycosylation events involved in cancer. Studies have shown that fucosyltransferase 8 (FUT8) is overexpressed in NSCLC and promotes lung cancer progression. However, there are no reports about the pathological role of fucosyltransferase 2 (FUT2) in lung cancer. To identify FUT2 associated with lung cancer, the expression and clinical significance of FUT2 in lung cancer was investigated by Real-Time PCR, Immunohistochemistry and Western Blot. In addition, we investigated the effect of knockdown FUT2 in lung adenocarcinoma cells. The results showed that the expression of FUT2 in lung adenocarcinoma is higher than that in adjacent noncancerous tissues. Knocking down FUT2 in A549 and H1299 cells decreased cell proliferation, migration and invasion, and increased cell apoptosis compared to corresponding control cells. Furthermore, Western Blot showed that knockdown FUT2 can impact the expression of migration-associated and apoptosis-associated proteins in A549 cells. Our results suggest that FUT2 may be associated with lung adenocarcinoma development and thus is a potential biomarker or/and therapeutic target in lung adenocarcinoma.