Glycans are major constituents of extracellular vesicles (EVs). Alterations in the glycosylation pathway are a common feature of cancer cells, which gives rise to de novo or increased synthesis of particular glycans. Therefore, glycans and glycoproteins have been widely used in the clinic as both stratification and prognosis cancer biomarkers. Interestingly, several of the known tumor-associated glycans have already been identified in cancer EVs, highlighting EV glycosylation as a potential source of circulating cancer biomarkers. These particles are crucial vehicles of cell–cell communication, being able to transfer molecular information and to modulate the recipient cell behavior. The presence of particular glycoconjugates has been described to be important for EV protein sorting, uptake and organ-tropism. Furthermore, specific EV glycans or glycoproteins have been described to be able to distinguish tumor EVs from benign EVs. In this review, the application of EV glycosylation in the development of novel EV detection and capture methodologies is discussed. In addition, we highlight the potential of EV glycosylation in the clinical setting for both cancer biomarker discovery and EV therapeutic delivery strategies.

CD44 isoforms are often upregulated in gastric cancer and have been associated with increased metastatic potential and poor survival. To evaluate the functional impact of O‐glycan truncation on CD44 we have analysed glyco‐engineered cancer cell models displaying shortened O‐glycans. Here, we demonstrate that induction of aberrant O‐glycan termination through various molecular mechanisms affects CD44 molecular features. We show that CD44 is a major carrier of truncated O‐glycans and that this truncation is accompanied by an increased hyaluronan binding capacity and affects extracellular shedding. In addition, short O‐glycans promoted the colocalization of CD44v6 with the receptor tyrosine kinase RON and concomitantly increased activation. Our in vitro findings were validated in gastric cancer clinical samples.

Alterations of the glycosylation machinery are common events in cancer, leading to the synthesis of aberrant glycan structures by tumor cells. Extracellular vesicles (EVs) play a modulatory role in cancer communication and progression, and interestingly, several tumor‐associated glycans have already been identified in cancer EVs. Nevertheless, the impact of 3D tumor architecture in the selective packaging of cellular glycans into EVs has never been addressed. In this work, the capacity of gastric cancer cell lines with differential glycosylation is evaluated in producing and releasing EVs when cultured under conventional 2D monolayer or in 3D culture conditions. Furthermore, the proteomic content is identified and specific glycans are studied in the EVs produced by these cells, upon differential spatial organization. Here, it is observed that although the proteome of the analyzed EVs is mostly conserved, an EV differential packaging of specific proteins and glycans is found. In addition, protein–protein interaction and pathway analysis reveal individual signatures on the EVs released by 2D‐ and 3D‐cultured cells, suggesting distinct biological functions. These protein signatures also show a correlation with clinical data. Overall, this data highlight the importance of tumor cellular architecture when assessing the cancer‐EV cargo and its biological role.

Heart failure (HF) prognosis, particularly readmission and mortality, remains poor irrespective of advances in its management. Growth differentiation factor 15 (GDF-15) is a member of the transforming growth fac-tor-beta (TGF-β) superfamily that arises as a promising biomarker to improve HF management, still despite two decades of extensive investigation some issues remain controversial. We performed a search in PubMed using the following Medical Subject Headings (MeSH) to identify relevant studies published in the last five years (after the latest updates of the guidelines by major Scientific Societies): “Growth Differentiation Fac-tor 15 (GDF-15)”, “heart failure”, “prognosis” and “diagnosis”. The search was supplemented by data pre-vious to this period, considered of utmost importance. A total of 105 articles written in English were re-trieved. Extensive evidence supports GDF-15 as an independent predictor of adverse outcomes across the heterogeneous HF spectrum and its addition to risk scores based on traditional biomarkers improves prog-nostic power. However, limited tissue specificity restricts its diagnostic value. Tailored treatment strategies and its role as a therapeutic target remain speculative, as the effect of HF therapies on GDF-15 levels are unclear and clinical trials have been unsuccessful. Large prospective studies are needed to validate its relia-bility for routine clinical use.

Heart failure (HF) prognosis, particularly readmission and mortality, remains poor irrespective of advances in its management. Growth differentiation factor-15 (GDF-15) is a member of the transforming growth factor-beta (TGF-β) superfamily that arises as a promising biomarker to improve HF management, still despite two decades of extensive investigation some issues remain controversial. We performed a search in PubMed using the following Medical Subject Headings (MeSH) to identify relevant studies published in the last five years (after the latest updates of the guidelines by major Scientific Societies): “Growth differentiation factor-15 (GDF-15)”, “heart failure”, “prognosis” and “diagnosis”. The search was supplemented by data previous to this period, considered of utmost importance. A total of 115 articles written in English were retrieved. Extensive evidence supports GDF-15 as an independent predictor of adverse outcomes across the heterogeneous HF spectrum and its addition to risk scores based on traditional biomarkers improves prognostic power. However, limited tissue specificity restricts its diagnostic value. Tailored treatment strategies and its role as a therapeutic target remain speculative, as the effect of HF therapies on GDF-15 levels is unclear and clinical trials have been unsuccessful. Large prospective studies are needed to validate its reliability for routine clinical use.