Applicability of Phenylhydrazine Labeling for Structural Studies of Fucosylated N-Glycans

Fucosylation is a common modification, and its site in glycans refers to different normal and pathological processes. Despite intensive research, there is still a lack of methods to discriminate unambiguously the fucose position in one-step. In this work, we propose utility of phenylhydrazine (PHN) labeling for structural studies of fucosylated N-glycans by tandem MALDI mass spectrometry (MS) in the positive ion mode. PHN-tag influences the production of specific ion types, and the MS/MS fragmentation pattern provides useful structural information. All types of core fucosylated N-glycans have produced two abundant ions consistent with B- and C-glycosidic cleavages corresponding to the loss of the FucGlcNAcPHN residue with a mass 457 and 441 Da from the parent ions. These types of fragment ions in N-glycans without a core fucose were associated with the loss of the GlcNAcPHN unit (311 and 295 Da), and fucose cleavage followed the loss of the chitobiose residue. Since diagnostic useful cleavages produce peaks with significant intensities, this approach is also beneficial for rapid recognition of antenna from core fucosylation in glycans detected with low abundances. Moreover, in multifucosylated glycans, this type of labeling allows to distinguish how many fucose residues are on the specific antenna and provides additional information on the topology of N-glycans, such as type of antennarity or identification of bisecting moiety. The practical applicability of the approach is demonstrated on the analysis of multifucosylated N-glycans detected with lower abundances in lung cancer samples.Fucosylation is a common modification, and its site in glycans refers to different normal and pathological processes. Despite intensive research, there is still a lack of methods to discriminate unambiguously the fucose position in one-step. In this work, we propose utility of phenylhydrazine (PHN) labeling for structural studies of fucosylated N-glycans by tandem MALDI mass spectrometry (MS) in the positive ion mode. PHN-tag influences the production of specific ion types, and the MS/MS fragmentation pattern provides useful structural information. All types of core fucosylated N-glycans have produced two abundant ions consistent with B- and C-glycosidic cleavages corresponding to the loss of the FucGlcNAcPHN residue with a mass 457 and 441 Da from the parent ions. These types of fragment ions in N-glycans without a core fucose were associated with the loss of the GlcNAcPHN unit (311 and 295 Da), and fucose cleavage followed the loss of the chitobiose residue. Since diagnostic useful cleavages produce peaks with significant intensities, this approach is also beneficial for rapid recognition of antenna from core fucosylation in glycans detected with low abundances. Moreover, in multifucosylated glycans, this type of labeling allows to distinguish how many fucose residues are on the specific antenna and provides additional information on the topology of N-glycans, such as type of antennarity or identification of bisecting moiety. The practical applicability of the approach is demonstrated on the analysis of multifucosylated N-glycans detected with lower abundances in lung cancer samples

N-Glycan profiling of lung adenocarcinoma in patients at different stages of disease

Lung adenocarcinoma (LAC) is the most common form of lung cancer that increases in non-smokers at younger age. Altered protein glycosylation is one of the hallmarks of malignancy, its role in cancer progression is still poorly understood. In this study, we report mass spectrometric (MS) analysis of N-glycans released from fresh or defrosted tissue specimens from 24 patients with LAC. Comparison of cancerous versus adjacent healthy tissues revealed substantial differences in N-glycan profiles associated with disease. The significant increase in paucimannose and high-mannose glycans with 6-9 mannose residues and decline in the sialylated complex biantenary core fucosylated glycan with composition NeuAcGal(2)GlcNAc(2)Man(3)GlcNAc(2)Fuc were general features of tumors. In addition, 42 new N-glycan compositions were detected in cancerous tissues. The prominent changes in advanced disease stages were mostly observed in core fucosylated N-glycans with additional fucose (Fuc) residue/s and enhanced branching with non-galactosylated N-acetyl-glucosamine (GlcNAc) units. Both of these monosaccharide types were linked preferably on the 6-antenna. Importantly, as compared with noncancerous tissues, a number of these significant changes were clearly detectable early on in stage I. Application of N-glycan data obtained from tissues was next assessed and validated for evaluation of small sized biopsies obtained via bronchoscopy. In summary, observed alterations and data of newly detected N-glycans expand knowledge about the glycosylation in LAC and may contribute to research in more tailored therapies. Moreover, the results demonstrate effectiveness of the presented approach for utility in rapid discrimination of cancerous from healthy lung tissues

Carboplatin with intravenous and subsequent oral administration of vinorelbine in resected non-small-cell-lung cancer in real-world set-up.

Adjuvant cisplatin-based chemotherapy is recommended for routine use in patients with Stage IIA, IIB or IIIA non-small cell lung cancer (NSCLC) after complete resection. Results obtained for Stage IB were not conclusive. While vinorelbine plus cisplatin is the preferred choice after resection, combining vinorelbine with carboplatin promises improved compliance and delivery of drugs due to lower toxicity. We evaluated the impact of this option on treatment compliance and survival under real-world conditions.A prospective, single-arm, multicenter, non-interventional study evaluated the tolerability, dose intensity and survival resulting from adjuvant use of intravenous carboplatin (AUC 5 on day 1) with vinorelbine administered both intravenously (25 mg/m2 on day 1) and orally (60 mg/m2 on day 8) within four cycles of 21 days each. A total of 74 patients with a median age of 64 years were observed.The mean number of accomplished cycles was 3.78, and 62 patients (83.7%) completed all four planned cycles. Relative dose intensity for carboplatin was 88.9%, for intravenous vinorelbine 93.1%, and for oral vinorelbine 83.2%. Median follow-up was 4.73 years. Median disease-specific survival (DSS) was 7.63 years, median overall survival (OS) was 5.90 years, median disease-free survival (DFS0) was 4.43 years, and five-year survival was 56.2%. TNM stage of disease significantly affected DSS and OS. Favorable survival was observed in females, nonsmokers, patients aged over 65 years, patient with prior lobectomy, patients with tumor of squamous histology, and those who finished the planned therapy, but the differences were non-significant.Adjuvant carboplatin with vinorelbine switched from intravenous to oral administration was shown to be a favorable regimen with regard to tolerability and safety. Compliance to therapy was high, and survival parameters were promising, showing that applied regimen can be another potential option for adjuvant chemotherapy in patients with NSCLC

Capillary Electrophoretic Analysis of Exhaled Breath Condensate in the Diagnosis of Gastroesophageal Reflux Disease

In this work, capillary electrophoresis with contactless conductometric detection (CCD) was used for the analysis of the ionic content of exhaled breath condensate (EBC) to differentiate between healthy individuals and patients with gastroesophageal reflux disease (GERD). The exhaled breath condensate was collected using a miniature sample collection device and the content analyzed using a separation electrolyte composed of 20 mM 2-(N-morpholino)ethanesulfonic acid, 20 mM L-histidine, 2 mM 18-Crown-6 and 30 M cetyltrimethylammonium bromide. The separation of anions took less than 2.5 minutes, while the cations were separated in less than 1.5 minutes. The most significantly elevated ions in the group of patients suffering from gastroesophageal reflux disease were chloride, nitrate, propionate and butyrate. Although the number of subjects was too small to draw definite conclusions with regard to the discriminatory power of these ions, the pilot data are promising for EBC as a useful non-invasive alternative for other methods used in the diagnosis of gastroesophageal reflux diseas

Disease free survival stratified by selected factors and covariates.

<p>Disease free survival stratified by selected factors and covariates.</p

Overall survival and disease specific survival.

<p>Overall survival and disease specific survival.</p

Overall survival by disease stage.

<p>Overall survival by disease stage.</p

Overall survival stratified by selected factors and covariates.

<p>Overall survival stratified by selected factors and covariates.</p

Disease specific survival stratified by selected factors and covariates.

<p>Disease specific survival stratified by selected factors and covariates.</p