Pharmacogenomic study of gemcitabine efficacy in patients with metastatic pancreatic cancer: A multicenter, prospective, observational cohort study (GENESECT study).

BACKGROUND: Genetic polymorphisms of molecules are known to cause individual differences in the therapeutic efficacy of anticancer drugs. However, to date, germline mutations (but not somatic mutations) for anticancer drugs have not been adequately studied. The objective of this study was to investigate the association between germline polymorphisms of gemcitabine metabolic and transporter genes with carbohydrate antigen 19-9 (CA 19-9) response (decrease ≥50% from the pretreatment level at 8 weeks) and overall survival (OS) in patients with metastatic pancreatic cancer who receive gemcitabine-based chemotherapy. METHODS: This multicenter, prospective, observational study enrolled patients with metastatic pancreatic cancer patients who were receiving gemcitabine monotherapy or gemcitabine plus nanoparticle albumin-bound paclitaxel combination chemotherapy. Thirteen polymorphisms that may be involved in gemcitabine responsiveness were genotyped, and univariate and multivariate logistic regression analyses were used to determine the association of these genotypes with CA 19-9 response and OS. The significance level was set at 5%. RESULTS: In total, 180 patients from 11 hospitals in Japan were registered, and 159 patients whose CA 19-9 response could be assessed were included in the final analysis. Patients who had a CA 19-9 response had significantly longer OS (372 vs. 241 days; p = .007). RRM1 2464A>G and RRM2 175T>G polymorphisms suggested a weak association with CA 19-9 response and OS, but it was not statistically significant. COX-2 -765G>C polymorphism did not significantly correlate with CA 19-9 response but was significantly associated with OS (hazard ratio, 2.031; p = .019). CONCLUSIONS: Genetic polymorphisms from the pharmacokinetics of gemcitabine did not indicate a significant association with efficacy, but COX-2 polymorphisms involved in tumor cell proliferation might affect OS.

hoxc12/c13 as key regulators for rebooting the developmental program in Xenopus limb regeneration.

During organ regeneration, after the initial responses to injury, gene expression patterns similar to those in normal development are reestablished during subsequent morphogenesis phases. This supports the idea that regeneration recapitulates development and predicts the existence of genes that reboot the developmental program after the initial responses. However, such rebooting mechanisms are largely unknown. Here, we explore core rebooting factors that operate during Xenopus limb regeneration. Transcriptomic analysis of larval limb blastema reveals that hoxc12/c13 show the highest regeneration specificity in expression. Knocking out each of them through genome editing inhibits cell proliferation and expression of a group of genes that are essential for development, resulting in autopod regeneration failure, while limb development and initial blastema formation are not affected. Furthermore, the induction of hoxc12/c13 expression partially restores froglet regenerative capacity which is normally very limited compared to larval regeneration. Thus, we demonstrate the existence of genes that have a profound impact alone on rebooting of the developmental program in a regeneration-specific manner.

Fgf10 mutant newts regenerate normal hindlimbs despite severe developmental defects.

In amniote limbs, Fibroblast Growth Factor 10 (FGF10) is essential for limb development, but whether this function is broadly conserved in tetrapods and/or involved in adult limb regeneration remains unknown. To tackle this question, we established Fgf10 mutant lines in the newt Pleurodeles waltl which has amazing regenerative ability. While Fgf10 mutant forelimbs develop normally, the hindlimbs fail to develop and downregulate FGF target genes. Despite these developmental defects, Fgf10 mutants were able to regenerate normal hindlimbs rather than recapitulating the embryonic phenotype. Together, our results demonstrate an important role for FGF10 in hindlimb formation, but little or no function in regeneration, suggesting that different mechanisms operate during limb regeneration versus development.

Pneumonia due to Achromobacter xylosoxidans with a chronic course resembling non-tuberculous mycobacterial infection.

Achromobacter xylosoxidans is a common bacterium that rarely causes pneumonia. Determining whether A. xylosoxidans is the cause of lung infection in patients suspected of having chronic infectious lung disease is challenging because it can present with colonization. We report a case of a 56-year-old immunocompetent woman suspected of having non-tuberculous mycobacteria (NTM) infection on imaging examination and monitored for 3 years. Sputum examinations revealed A. xylosoxidans several times, and it was determined to be a colonization. A. xylosoxidans was isolated from bronchial lavage fluid and aspirated sputum, but no evidence of NTM was observed. She was diagnosed with A. xylosoxidans infection and given ceftazidime for 2 weeks. Her symptoms and imaging findings improved rapidly after treatment, without recurrences. A. xylosoxidans rarely causes chronic lower respiratory tract infections similar to NTM in immunocompetent patients. A. xylosoxidans may be a target for treatment when detected in lower respiratory tract specimens.

Single-molecule localization microscopy reveals STING clustering at the trans-Golgi network through palmitoylation-dependent accumulation of cholesterol.

Stimulator of interferon genes (STING) is critical for the type I interferon response to pathogen- or self-derived DNA in the cytosol. STING may function as a scaffold to activate TANK-binding kinase 1 (TBK1), but direct cellular evidence remains lacking. Here we show, using single-molecule imaging of STING with enhanced time resolutions down to 5 ms, that STING becomes clustered at the trans-Golgi network (about 20 STING molecules per cluster). The clustering requires STING palmitoylation and the Golgi lipid order defined by cholesterol. Single-molecule imaging of TBK1 reveals that STING clustering enhances the association with TBK1. We thus provide quantitative proof-of-principle for the signaling STING scaffold, reveal the mechanistic role of STING palmitoylation in the STING activation, and resolve the long-standing question of the requirement of STING translocation for triggering the innate immune signaling.

A multicenter phase II trial of the triplet antiemetic therapy with palonosetron, aprepitant, and olanzapine for a cisplatin-containing regimen. - PATROL-I.

Dexamethasone is one of the key antiemetic agents and is widely used even now. However, dexamethasone has been associated with several adverse reactions even after short-term administration. Therefore, developing a steroid-free antiemetic regimen is an important issue to consider. Thus, the purpose of this study was to investigate the efficacy and safety of palonosetron, aprepitant, and olanzapine in a multi-institutional phase II study. Chemotherapy-naive patients scheduled to receive cisplatin were enrolled and evaluated for the occurrence of chemotherapy-induced nausea and vomiting during 120 h after chemotherapy. The primary endpoint of the study was total control (TC) in the overall phase. The key secondary endpoint was complete response (CR), which was assessed in the acute, delayed, and overall phase, respectively. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Events. Eighty-five patients were enrolled from 8 centers in Japan, of which 83 were evaluable for analyses. The percentage of patients who achieved TC during the overall phase was 31.3%. CR was achieved in 61.4%, 84.3%, and 65.1% of patients during the overall, acute, and delayed phases, respectively. The most frequently reported adverse event was anorexia. The primary endpoint was below the threshold and we could not find benefit in the dexamethasone-free regimen, but CR during the overall phase was similar to that of the conventional three-drug regimen. This antiemetic regimen without dexamethasone might be an option for patients for whom corticosteroids should not be an active application.

A CRISPR-Cas9-mediated versatile method for targeted integration of a fluorescent protein gene to visualize endogenous gene expression in Xenopus laevis.

Xenopus laevis is a widely used model organism in developmental and regeneration studies. Despite several reports regarding targeted integration techniques in Xenopus, there is still room for improvement of them, especially in creating reporter lines that rely on endogenous regulatory enhancers/promoters. We developed a CRISPR-Cas9-based simple method to efficiently introduce a fluorescent protein gene into 5' untranslated regions (5'UTRs) of target genes in Xenopus laevis. A donor plasmid DNA encoding an enhanced green fluorescent protein (eGFP) flanked by a genomic fragment ranging from 66 bp to 878 bp including target 5'UTR was co-injected into fertilized eggs with a single guide RNA and Cas9 protein. Injections for krt12.2.L, myod1.S, sox2.L or brevican.S resulted in embryos expressing eGFP fluorescence in a tissue-specific manner, recapitulating endogenous expression of target genes. Integrations of the donor DNA into the target regions were examined by genotyping PCR for the eGFP-expressing embryos. The rate of embryos expressing the specific eGFP varied from 2.1% to 13.2% depending on the target locus and length of the genomic fragment in the donor plasmids. Germline transmission of an integrated DNA was observed. This simple method provides a powerful tool for exploring gene expression and function in developmental and regeneration research in X. laevis.

[Evaluation of the Leftover Capecitabine Tablets in Adjuvant CAPOX Chemotherapy for Gastric Cancer].

Since it is important that patients take their oral anticancer therapy as prescribed, pharmacists need to assess adherence. In addition, oral anticancer drugs are expensive, and reuse of leftover drugs at outpatient pharmacy clinics is useful in reducing drug costs. The present study aimed to clarify when and why patients have leftover capecitabine tablets, and the cost of leftover capecitabine tablets reused at an outpatient pharmacy clinic, focusing on adjuvant capecitabine plus oxaliplatin (CAPOX) chemotherapy for gastric cancer. We retrospectively studied patients who received adjuvant CAPOX chemotherapy for gastric cancer between November 1, 2015, and April 30, 2021, at the Cancer Institute Hospital of the Japanese Foundation for Cancer Research. The cost of leftover capecitabine reused by pharmacists was calculated based on the National Health Insurance drug price standard for the study period. This study included 64 patients who received adjuvant CAPOX chemotherapy. Thirty-seven patients had 152 leftover capecitabine tablets. The most common reasons for leftover capecitabine tablets were nausea and vomiting (21.7%), missed doses (18.4%), and diarrhea (13.2%). The leftover capecitabine tablets for 25 patients were reused at the outpatient pharmacy clinic at a cost of JPY 604142.8 (JPY 24165.7 per patient). The study results suggest that evaluating capecitabine adherence and the reasons for leftover capecitabine tablets at outpatient pharmacy clinics as well as reusing leftover medication can contribute to reducing drug costs.

Association between middle cerebral artery morphology and branch atheromatous disease.

INTRODUCTION: Branch atheromatous disease (BAD) is a type of cerebral infarction caused by stenosis or occlusion at the entrance of the penetrating branch due to the presence of plaque. Despite its clinical significance, it is not clear how these plaques are formed. Focal geometrical characteristics are expected to be as important as vascular risk factors in the development of atherosclerosis. This study aimed to analyze the association between middle cerebral artery (MCA) geometric features and the onset of BAD. Shear stress results from the blood flow exerting force on the inner wall of the vessels and places with low wall shear stress may be prone to atherosclerosis. At the curvature of blood vessels, the shear stress is weak on the inside of the curve and plaque is likely to form. When this is applied to the MCA M1 segment, downward type M1 is likely to form plaques on the superior side. Because the lenticulostriate artery usually branches off from the superior side of the MCA M1 segment, in downward type M1, a plaque is likely to be formed at the entrance of the penetrating branch, and for that reason, BAD is likely to onset. METHODS: We retrospectively reviewed hospitalized stroke patients with BAD and investigated the morphology of their MCA using magnetic resonance imaging. The M1 segment was classified as straight or curved. Additionally, we compared the difference between the symptomatic and the asymptomatic side. Data regarding patients' medical history were also collected. RESULTS: A total of 56 patients with lenticulostriate artery infarctions and BAD were analyzed. On the symptomatic side, downward type M1 accounted for the largest proportion at 44%, whereas on the asymptomatic side, it was the lowest, at 16%. CONCLUSION: A downward type MCA may be associated with the onset of BAD and the morphological characteristics might affect the site of plaque formation. J. Med. Invest. 70 : 411-414, August, 2023.

Influence of menopause on chemotherapy-induced nausea and vomiting in highly emetogenic chemotherapy for breast cancer: A retrospective observational study.

BACKGROUND: Female sex and younger age are reported risk factors for chemotherapy-induced nausea and vomiting (CINV) in highly emetogenic chemotherapy, but the underlying mechanism has not been elucidated. The purpose of this study was to clarify the impact of menopause on CINV. METHODS: This retrospective observational study analyzed data from consecutive patients who received their first cycle of perioperative anthracycline-based chemotherapy for breast cancer between January 2018 and June 2020. The endpoints were association between CINV (vomiting, ≥Grade 2 nausea, complete response [CR] failure) and menopause as well as the association between CINV and follicle-stimulating hormone [FSH]/estradiol [E2]. RESULTS: Data for 639 patients were analyzed. Among these patients, 109 (17.1%) received olanzapine (four antiemetic combinations) and 530 (82.9%) did not (three antiemetic combinations). Premenopausal state (amenorrhea lasting ≥12 months) was significantly associated with ≥Grade 2 nausea and CR failure in univariate analysis but not in multivariate analysis. The premenopausal FSH/E2 group (defined by serum levels; FSH <40 mIU/mL and E2 ≥20 pg/mL) had a significantly higher rate of ≥Grade 2 nausea than the postmenopausal FSH/E2 group (FSH ≥40 mIU/mL and E2 <20 pg/mL) (48.8% vs. 18.8%, p = 0.023). CONCLUSIONS: Our results suggest that changes in FSH and E2 due to menopause may affect the severity of nausea and that FSH and E2 (especially FSH) levels might be useful indicators for CINV risk assessment.

Development of ultrafast camera-based single fluorescent-molecule imaging for cell biology.

The spatial resolution of fluorescence microscopy has recently been greatly enhanced. However, improvements in temporal resolution have been limited, despite their importance for examining living cells. Here, we developed an ultrafast camera system that enables the highest time resolutions in single fluorescent-molecule imaging to date, which were photon-limited by fluorophore photophysics: 33 and 100 µs with single-molecule localization precisions of 34 and 20 nm, respectively, for Cy3, the optimal fluorophore we identified. Using theoretical frameworks developed for the analysis of single-molecule trajectories in the plasma membrane (PM), this camera successfully detected fast hop diffusion of membrane molecules in the PM, previously detectable only in the apical PM using less preferable 40-nm gold probes, thus helping to elucidate the principles governing the PM organization and molecular dynamics. Furthermore, as described in the companion paper, this camera allows simultaneous data acquisitions for PALM/dSTORM at as fast as 1 kHz, with 29/19 nm localization precisions in the 640 × 640 pixel view-field.

Ultrafast single-molecule imaging reveals focal adhesion nano-architecture and molecular dynamics.

Using our newly developed ultrafast camera described in the companion paper, we reduced the data acquisition periods required for photoactivation/photoconversion localization microscopy (PALM, using mEos3.2) and direct stochastic reconstruction microscopy (dSTORM, using HMSiR) by a factor of ≈30 compared with standard methods, for much greater view-fields, with localization precisions of 29 and 19 nm, respectively, thus opening up previously inaccessible spatiotemporal scales to cell biology research. Simultaneous two-color PALM-dSTORM and PALM-ultrafast (10 kHz) single fluorescent-molecule imaging-tracking has been realized. They revealed the dynamic nanoorganization of the focal adhesion (FA), leading to the compartmentalized archipelago FA model, consisting of FA-protein islands with broad diversities in size (13-100 nm; mean island diameter ≈30 nm), protein copy numbers, compositions, and stoichiometries, which dot the partitioned fluid membrane (74-nm compartments in the FA vs. 109-nm compartments outside the FA). Integrins are recruited to these islands by hop diffusion. The FA-protein islands form loose ≈320 nm clusters and function as units for recruiting FA proteins.

Protocols for transgenesis at a safe harbor site in the Xenopus laevis genome using CRISPR-Cas9.

We have established a new transgenesis protocol based on CRISPR-Cas9, "New and Easy XenopusTransgenesis (NEXTrans)," and identified a novel safe harbor site in African clawed frogs, Xenopus laevis. We describe steps in detail for the construction of NEXTrans plasmid and guide RNA, CRISPR-Cas9-mediated NEXTrans plasmid integration into the locus, and its validation by genomic PCR. This improved strategy allows us to simply generate transgenic animals that stably express the transgene. For complete details on the use and execution of this protocol, please refer to Shibata et al. (2022).1.

Recently developed glycosphingolipid probes and their dynamic behavior in cell plasma membranes as revealed by single-molecule imaging.

Glycosphingolipids, including gangliosides, are representative lipid raft markers that perform a variety of physiological roles in cell membranes. However, studies aimed at revealing their dynamic behavior in living cells are rare, mostly due to a lack of suitable fluorescent probes. Recently, the ganglio-series, lacto-series, and globo-series glycosphingolipid probes, which mimic the behavior of the parental molecules in terms of partitioning to the raft fraction, were developed by conjugating hydrophilic dyes to the terminal glycans of glycosphingolipids using state-of-art entirely chemical-based synthetic techniques. High-speed, single-molecule observation of these fluorescent probes revealed that gangliosides were scarcely trapped in small domains (100 nm in diameter) for more than 5 ms in steady-state cells, suggesting that rafts including gangliosides were always moving and very small. Furthermore, dual-color, single-molecule observations clearly showed that homodimers and clusters of GPI-anchored proteins were stabilized by transiently recruiting sphingolipids, including gangliosides, to form homodimer rafts and the cluster rafts, respectively. In this review, we briefly summarize recent studies, the development of a variety of glycosphingolipid probes as well as the identification of the raft structures including gangliosides in living cells by single-molecule imaging.

Efficacy of Olanzapine in Addition to Standard Triplet Antiemetic Therapy for Cisplatin-Based Chemotherapy: A Secondary Analysis of the J-FORCE Randomized Clinical Trial.

Importance: It is unknown whether olanzapine combined with triplet antemetic therapy is effective for all patients undergoing highly emetogenic chemotherapy. A secondary analysis of randomized clinical trials using olanzapine may provide insight into the effectiveness of olanzapine for chemotherapy-induced nausea and vomiting (CINV), including cisplatin. Objective: To examine the add-on effect of olanzapine according to risk factors for CINV. Design, Setting, and Participants: This preplanned secondary analysis evaluated results of the J-FORCE trial, a large double-blind, placebo-controlled phase 3 randomized clinical trial conducted in Japan from February 9, 2017, to July 18, 2018. Participants were enrolled from 26 participating hospitals across Japan and included patients aged 20 to 75 years who had a malignant tumor and were cisplatin-naive. The efficacy analysis population of the J-FORCE trial was analyzed according to allocation adjustment factors (sex [male or female], age [≥55 years or <55 years], and cisplatin dose [≥70 mg/m2 or <70 mg/m2]) and patient-related risk factors (history of motion sickness, drinking habit [defined as alcoholic drinks consumption in excess of occasional drinking], and history of morning sickness during pregnancy). Statistical analysis was performed from February 18 to April 18, 2020. Interventions: Patients were randomized 1:1 to receive 5 mg of olanzapine or placebo combined with standard triplet antiemetic therapy. Main Outcomes and Measures: The primary end point was complete response (CR, defined as no vomiting and no use of rescue medication) in the delayed phase (24-120 hours after cisplatin-based chemotherapy administration). Secondary end points were CR, complete control, and total control in the acute, delayed, and overall phases for 6 CINV risk factors as well as time to treatment failure. The CR point estimates and 95% CIs of the differences between groups were calculated, and a Mantel-Haenszel test was performed. Results: Of the 705 patients (mean [SD] age, 63.0 [9.2] years; 471 males [66.8%]) included in the efficacy analysis population; 581 patients (82.4%) were 55 years or older, and 526 (74.6%) were treated with a cisplatin dose of 70 mg/m2 or more. Risk difference (RD) for a CR in the delayed phase was significantly greater in the olanzapine group than the placebo group in males (RD, 12.6% [95% CI, 5.0%-20.1%]; P = .001); in females (RD, 14.5% [95% CI, 2.2%-26.3%]; P = .02); in those 55 years or older (RD, 11.1% [95% CI, 3.9%-18.2%]; P = .003) or younger than 55 years (RD, 23.6% [95% CI, 7.3%-38.3%]; P = .005); for a cisplatin dose of 70 mg/m2 or more (RD, 13.5% [95% CI, 5.9%-21.0%]; P < .001); for those without a history of motion sickness (RD, 13.9% [95% CI, 6.9%-20.6%]; P < .001); for those with a drinking habit (RD, 14.9% [95% CI, 6.1%-23.4%]; P = .001) or without a drinking habit (RD, 12.0% [95% CI, 2.5%-21.3%]; P = .01); and for those with a history of morning sickness during pregnancy (RD, 27.2% [9.7%-42.6%]; P = .002). In other subgroups, a delayed CR was higher in the olanzapine group than the placebo group, although not significantly higher. Conclusions and Relevance: Results of this study suggest a benefit of using 5 mg of olanzapine plus triplet antiemetic therapy to counter CINV regardless of the presence or absence of risk factors. Trial Registration: University Hospital Medical Information Network Clinical Trials Registry Identifier: UMIN000024676.

Cholesterol- and actin-centered view of the plasma membrane: updating the Singer-Nicolson fluid mosaic model to commemorate its 50th anniversary†.

Two very polarized views exist for understanding the cellular plasma membrane (PM). For some, it is the simple fluid described by the original Singer-Nicolson fluid mosaic model. For others, due to the presence of thousands of molecular species that extensively interact with each other, the PM forms various clusters and domains that are constantly changing and therefore, no simple rules exist that can explain the structure and molecular dynamics of the PM. In this article, we propose that viewing the PM from its two predominant components, cholesterol and actin filaments, provides an excellent and transparent perspective of PM organization, dynamics, and mechanisms for its functions. We focus on the actin-induced membrane compartmentalization and lipid raft domains coexisting in the PM and how they interact with each other to perform PM functions. This view provides an important update of the fluid mosaic model.

[Education Aimed at Patient Safety Management of Chemotherapy Conducted at University Education Sites].

The School Education Law was revised in 2006, and the university pharmacy education system and the national pharmacist examination system were changed. In line with the advancement of medical technology and the division of labor, 16 years have passed since the length of undergraduate pharmacy education was extended from 4 to 6 years in order to foster highly qualified pharmacists. During this period, the curriculum for practical training has been revised, and lectures and exercises focused on clinical education have been incorporated to foster pharmacists who can be useful in the medical field. In the area of cancer drug therapy, the university provides students with opportunities to learn about the basic mechanisms of action and side effects of anticancer drugs, but there is little coverage of clinical guidelines and pharmacological management of the latest therapies, such as cancer immunotherapy. Prior to my arrival at Hoshi University, I was involved in clinical work and clinical research at an oncology hospital for 13 years. Since my arrival, I have been exploring the gap between oncology pharmacotherapy and pharmacy education, and have been working to fill it. We have incorporated new curricula, such as exercises in formulation suggestions, lectures to deepen understanding of guidelines and supportive care, and information on the latest cancer drug therapies, such as cancer immunotherapy. This paper outlines the pharmacy education required to produce pharmacists who can practice safe cancer drug therapy.

CRISPR-Cas9-Based Functional Analysis in Amphibians: Xenopus laevis, Xenopus tropicalis, and Pleurodeles waltl.

Amphibians have made many fundamental contributions to our knowledge, from basic biology to biomedical research on human diseases. Current genome editing tools based on the CRISPR-Cas system enable us to perform gene functional analysis in vivo, even in non-model organisms. We introduce here a highly efficient and easy protocol for gene knockout, which can be used in three different amphibians seamlessly: Xenopus laevis, Xenopus tropicalis, and Pleurodeles waltl. As it utilizes Cas9 ribonucleoprotein complex (RNP) for injection, this cloning-free method enables researchers to obtain founder embryos with a nearly complete knockout phenotype within a week. To evaluate somatic mutation rate and its correlation to the phenotype of a Cas9 RNP-injected embryo (crispant), we also present accurate and cost-effective genotyping methods using pooled amplicon-sequencing and a user-friendly web-based tool.

Association between pazopanib exposure and safety in Japanese patients with renal cell carcinoma or soft tissue sarcoma.

The safety and effectiveness of pazopanib are related to plasma trough concentrations in renal cell carcinoma (RCC); however, data on pazopanib plasma trough concentrations with soft tissue sarcoma (STS) are limited. This study investigated the relationship between plasma trough concentrations and pazopanib safety in 45 Japanese patients with RCC or STS. Among the 33 patients included, the median pazopanib trough concentration was 37.5 (range, 12.1-67.6) µg/mL, which was not significantly different between Japanese RCC and STS patients. The plasma trough concentrations showed significant and positive correlations with aspartate aminotransferase and alanine aminotransferase values in blood samples taken for pharmacokinetic measurements after the administration. The incidence of pazopanib treatment discontinuation were significantly higher in RCC patients (p = 0.027). The primary reason for treatment discontinuation was hepatic dysfunction (5/6, 83.3%). Furthermore, this study revealed that pazopanib trough concentration was affected significantly by proton pump inhibitors but not by histamine 2-receptor blockers. In conclusion, the observed pazopanib trough levels and their safety in the Japanese RCC and STS populations in this study were similar to those of the global population. This is the first study to correlate the hepatotoxicity and pharmacokinetic property of pazopanib plasma trough levels by comparing Japanese patients with RCC or STS.

N-acetylglucosaminyltransferase-V (GnT-V)-enriched small extracellular vesicles mediate N-glycan remodeling in recipient cells.

Small extracellular vesicles (sEVs) secreted from cancer cells play pivotal roles in cancer metastasis and malignancy by transferring biomolecules and conditioning future metastatic sites. Studies have elucidated structures and functions of glycans on sEVs; however, whether sEVs remodel glycans in recipient cells remains poorly understood. Here, we examined the enzyme activity of glycosyltransferases for complex N-glycan biosynthesis in cancer-derived sEVs and discovered that cancer-related glycosyltransferase, N-acetylglucosaminyltransferase-V (GnT-V, a.k.a. MGAT5), is selectively enriched in sEVs among various glycosyltransferases. GnT-V in sEVs is a cleaved form, and cleavage by SPPL3 protease is necessary for loading GnT-V in sEVs. Fractionation experiments and single-particle imaging further revealed that GnT-V was enriched in non-exosomal sEVs. Strikingly, we found that enzymatically active GnT-V in sEVs was transferred to recipient cells and the N-glycan structures of recipient cells were remodeled to express GnT-V-produced glycans. Our results suggest GnT-V-enriched sEVs' role in glycan remodeling in cancer metastasis.