In recent years the significance of O-glycans has become known, and there has been a demand for the analysis of O-glycopeptides. Analysis of O-glycopeptides has not progressed as much as that of N-glycopeptides, because, in conventional tandem mass spectrometry (MS/MS) measurements, O-glycans are easily detached from the peptides. This results in the loss of information on the glycosylation site, making it difficult to identify the glycopeptide containing the glycosylation site. Recently, MS/MS methods such as electron transfer dissociation (ETD) that fragment only the backbone of the peptide chain without releasing the glycans have been developed. Here, I summarize recent progress in the analysis of O-glycopeptides and discuss the prospects for their analysis.

Sialyl-Tn (sTn) antigen, a cancer-associated carbohydrate antigen, is used in the clinical practice as a tumor marker strongly correlated with poor prognosis in cancer patients, but its biological role in pathogenesis remains poorly understood. Regulation of the cancer microenvironment through direct and indirect cell–cell communication in tumor tissue is crucial during cancer progression. Recently, we have demonstrated that sTn antigen activates extracellular vesicle production in cancer cells and transfers focal adhesion kinase to the target cells. In this review, we present that sTn antigen plays an important role in the remodeling of the cancer microenvironment and cancer progression.

Archaea represent a third domain of life distinct from bacteria and eukaryotes. Although they are commonly recognized as inhabitants of extreme environments, they are also widely detected in the human microbiota, including the oral cavity, skin, and gut. This mini-review explores archaeal glyceroglycolipids, focusing on their functions and potential in drug development. Archaeosomes, formed from these lipids, exhibit greater stability than conventional liposomes, making them promising vaccine carriers. Symbiotic archaeal glyceroglycolipids activate the innate immune receptor macrophage-inducible C-type lectin (Mincle), inducing T-helper 1 (Th1)/Th17 responses and functioning as potential vaccine adjuvants.

In recent years the significance of O-glycans has become known, and there has been a demand for the analysis of O-glycopeptides. Analysis of O-glycopeptides has not progressed as much as that of N-glycopeptides, because, in conventional tandem mass spectrometry (MS/MS) measurements, O-glycans are easily detached from the peptides. This results in the loss of information on the glycosylation site, making it difficult to identify the glycopeptide containing the glycosylation site. Recently, MS/MS methods such as electron transfer dissociation (ETD) that fragment only the backbone of the peptide chain without releasing the glycans have been developed. Here, I summarize recent progress in the analysis of O-glycopeptides and discuss the prospects for their analysis.

Sialyl-Tn (sTn) antigen, a cancer-associated carbohydrate antigen, is used in the clinical practice as a tumor marker strongly correlated with poor prognosis in cancer patients, but its biological role in pathogenesis remains poorly understood. Regulation of the cancer microenvironment through direct and indirect cell–cell communication in tumor tissue is crucial during cancer progression. Recently, we have demonstrated that sTn antigen activates extracellular vesicle production in cancer cells and transfers focal adhesion kinase to the target cells. In this review, we present that sTn antigen plays an important role in the remodeling of the cancer microenvironment and cancer progression.

Archaea represent a third domain of life distinct from bacteria and eukaryotes. Although they are commonly recognized as inhabitants of extreme environments, they are also widely detected in the human microbiota, including the oral cavity, skin, and gut. This mini-review explores archaeal glyceroglycolipids, focusing on their functions and potential in drug development. Archaeosomes, formed from these lipids, exhibit greater stability than conventional liposomes, making them promising vaccine carriers. Symbiotic archaeal glyceroglycolipids activate the innate immune receptor macrophage-inducible C-type lectin (Mincle), inducing T-helper 1 (Th1)/Th17 responses and functioning as potential vaccine adjuvants.