A novel approach to evaluation of tumor response for advanced pulmonary adenocarcinoma using the intertumoral heterogeneity response score.

Treatment response and prognosis estimation in advanced pulmonary adenocarcinoma are challenged by the significant heterogeneity of the disease. The current Response Evaluation Criteria in Solid Tumors (RECIST) criteria, despite providing a basis for solid tumor response evaluation, do not fully encompass this heterogeneity. To better represent these nuances, we introduce the intertumoral heterogeneity response score (THRscore), a measure built upon and expanding the RECIST criteria. This retrospective study included patients with 3-10 measurable advanced lung adenocarcinoma lesions who underwent first-line chemotherapy or targeted therapy. The THRscore, derived from the coefficient of variation in size for each measurable tumor before and 4-6 weeks posttreatment, unveiled a correlation with patient outcomes. Specifically, a high THRscore was associated with shorter progression-free survival, lower tumor response rate, and a higher tumor mutation burden. These associations were further validated in an external cohort, confirming THRscore's effectiveness in stratifying patients based on progression risk and treatment response, and enhancing the utility of RECIST in capturing complex tumor behaviors in lung adenocarcinoma. These findings affirm the promise of THRscore as an enhanced tool for tumor response assessment in advanced lung adenocarcinoma, extending the RECIST criteria's utility.

Adjuvant and neo-adjuvant immunotherapy in resectable non-small cell lung cancer (NSCLC): Current status and perspectives.

Surgery followed by adjuvant chemotherapy is the standard of care for selected patients with early-stage or locally advanced non-small cell lung cancer (NSCLC). However, many of these patients still experience postoperative recurrence at 5 years. At present, peri-operative treatment methods are emerging to prevent early relapse, such as targeted therapy and immunotherapy. Investigation on predictive biomarkers of responses to adjuvant and neoadjuvant therapies is also continuously ongoing. Immunotherapy represented by immune checkpoint inhibitors (ICIs), either by monotherapy or in combination with chemotherapy, has shown benefit in promoting pathological responses and prolonging survival for patients with NSCLC without oncogenic mutations. Exploratory studies have also provided evidence regarding the selection of patients who benefit from ICI-based perioperative treatment. This review focuses on the existing data of current clinical trials of adjuvant and neoadjuvant strategies with ICIs in resectable NSCLC, the exploration of predictive biomarkers, and the perspectives and urgent challenges in the future.

Cerebrospinal fluid circulating tumor DNA contributes to the detection and characterization of leptomeningeal metastasis in non-small cell lung cancer.

PURPOSE: Cerebrospinal fluid (CSF) has revealed the unique genetic characteristics of leptomeningeal metastasis (LM) from non-small cell lung cancer (NSCLC). However, the research in this area is still very limited. METHODS: Patients with LM from NSCLC (n = 80) were retrospectively analyzed. Circulating tumor DNA (ctDNA) in CSF was tested by next-generation sequencing (NGS), with paired extracranial tissue or plasma samples included for comparison. An independent non-LM cohort (n = 100) was also analyzed for comparative purposes. Clinical outcomes were compared with Kaplan-Meier log-rank test and Cox proportional hazards methodologies. RESULTS: An overwhelming 93.8% of patients carried druggable mutations in NSCLC LM, with EGFR (78.8%) being the most prevalent. Notably, 4 patients who tested negative for driver genes in extracranial samples surprisingly showed EGFR mutations in their CSF and subsequently benefited from targeted therapy. There was a clear difference in genetic profiles between CSF and extracranial samples, with CSF showing more driver gene detections, increased Copy Number Variations (CNVs), and varied resistance mechanisms among individuals. Abnormalities in cell-cycle regulatory molecules were highly enriched in LM (50.9% vs 31.0%, p = 0.017), and CDKN2A/2B deletions were identified as an independent poor prognostic factor for LM patients, with a significant reduction in median OS (p = 0.013), supported by multivariate analysis (HR 2.63, 95% CI 1.32-5.26, p = 0.006). CONCLUSIONS: CSF-based ctDNA analysis is crucial for detecting and characterizing genetic alterations in NSCLC LM. The distinct genetic profiles in CSF and extracranial tissues emphasize the need for personalized treatment approaches.

Genomic characterisation of de novo EGFR copy number gain and its impact on the efficacy of first-line EGFR-tyrosine kinase inhibitors for EGFR mutated non-small cell lung cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation generally respond well to epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs). However, genomic characterisation of de novo EGFR copy number gain (CNG) and its impact on the efficacy of first-line EGFR-TKIs remains unclear. METHODS: This multicenter, retrospective and real-world study included two cohorts that enroled EGFR mutant NSCLC patients. EGFR CNG was tested by next-generation sequencing of untreated tissue specimens. Cohort 1 detected the impact of EGFR CNG on first-line EGFR-TKIs treatment, and cohort 2 explored the genomic characterisation. RESULTS: Cohort 1 enroled 355 patients from four cancer centres between January 2013 and March 2022. The patients were divided into three groups, included the EGFR non-CNG, EGFR CNG, and EGFR uncertain-CNG. No significant difference in progression-free survival (PFS) was found between the three groups (10.0 months vs. 10.8 months vs. 9.9 months, respectively, p = 0.384). Furthermore, the overall response rate was not statistically significant in the EGFR CNG group compared to the EGFR non-CNG or uncertain arm (70.3% vs. 63.2% vs. 54.5%, respectively, p = 0.154). Cohort 2 included 7876 NSCLC patients with 16.4% showing EGFR CNG. Gene mutations such as TP53, IKZF1, RAC1, MYC, MET, CDKN2A/B and alterations of the metabolic-related and ERK signalling pathway were significantly associated with patients with EGFR CNG compared to those without. CONCLUSIONS: De novo EGFR CNG had no effect on the efficacy of first-line EGFR-TKI treatment in EGFR mutant NSCLC patients, and tumours with EGFR CNG had more complex genomic profiles than those without.

Front-line therapy for brain metastases and non-brain metastases in advanced epidermal growth factor receptor-mutated non-small cell lung cancer: a network meta-analysis.

BACKGROUND: The brain is a common metastatic site in patients with non-small cell lung cancer (NSCLC), resulting in a relatively poor prognosis. Systemic therapy with epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) is recommended as the first-line treatment for EGFR -mutated, advanced NSCLC patients. However, intracranial activity varies in different drugs. Thus, brain metastasis (BM) should be considered when choosing the treatment regimens. We conducted this network meta-analysis to explore the optimal first-line therapeutic schedule for advanced EGFR -mutated NSCLC patients with different BM statuses. METHODS: Randomized controlled trials focusing on EGFR-TKIs (alone or in combination) in advanced and EGFR -mutant NSCLC patients, who have not received systematic treatment, were systematically searched up to December 2021. We extracted and analyzed progression-free survival (PFS) and overall survival (OS). A network meta-analysis was performed with the Bayesian statistical model to determine the survival outcomes of all included therapy regimens using the R software. Hazard ratios (HRs) and 95% confidence intervals (CIs) were used to compare intervention measures, and overall rankings of therapies were estimated under the Bayesian framework. RESULTS: This analysis included 17 RCTs with 5077 patients and 12 therapies, including osimertinib + bevacizumab, aumolertinib, osimertinib, afatinib, dacomitinib, standards of care (SoC, including gefitinib, erlotinib, or icotinib), SoC + apatinib, SoC + bevacizumab, SoC + ramucirumab, SoC + pemetrexed based chemotherapy (PbCT), PbCT, and pemetrexed free chemotherapy (PfCT). For patients with BM, SoC + PbCT improved PFS compared with SoC (HR = 0.40, 95% CI: 0.17-0.95), and osimertinib + bevacizumab was most likely to rank first in PFS, with a cumulative probability of 34.5%, followed by aumolertinib, with a cumulative probability of 28.3%. For patients without BM, osimertinib + bevacizumab, osimertinib, aumolertinib, SoC + PbCT, dacomitinib, SoC + ramucirumab, SoC + bevacizumab, and afatinib showed superior efficacy compared with SoC (HR = 0.43, 95% CI: 0.20-0.90; HR = 0.46, 95% CI: 0.31-0.68; HR = 0.51, 95% CI: 0.34-0.77; HR = 0.50, 95% CI: 0.38-0.66; HR = 0.62, 95% CI: 0.43-0.89; HR = 0.64, 95% CI: 0.44-0.94; HR = 0.61, 95% CI: 0.48-0.76; HR = 0.71, 95% CI: 0.50-1.00), PbCT (HR = 0.29, 95% CI: 0.11-0.74; HR = 0.31, 95% CI: 0.15-0.62; HR = 0.34, 95% CI: 0.17-0.69; HR = 0.34, 95% CI: 0.18-0.64; HR = 0.42, 95% CI: 0.21-0.82; HR = 0.43, 95% CI: 0.22-0.87; HR = 0.41, 95% CI: 0.22-0.74; HR = 0.48, 95% CI: 0.31-0.75), and PfCT (HR = 0.14, 95% CI: 0.06-0.32; HR = 0.15, 95% CI: 0.09-0.26; HR = 0.17, 95% CI: 0.09-0.29; HR = 0.16, 95% CI: 0.10-0.26; HR = 0.20, 95% CI: 0.12-0.35; HR = 0.21, 95% CI: 0.12-0.39; HR = 0.20, 95% CI: 0.12-0.31; HR = 0.23, 95% CI: 0.16-0.34) in terms of PFS. And, SoC + apatinib showed relatively superior PFS when compared with PbCT (HR = 0.44, 95% CI: 0.22-0.92) and PfCT (HR = 0.21, 95% CI: 0.12-0.39), but similar PFS to SoC (HR = 0.65, 95% CI: 0.42-1.03). No statistical differences were observed for PFS in patients without BM between PbCT and SoC (HR = 1.49, 95% CI: 0.84-2.64), but both showed favorable PFS when compared with PfCT (PfCT vs. SoC, HR = 3.09, 95% CI: 2.06-4.55; PbCT vs. PfCT, HR = 0.14, 95% CI: 0.06-0.32). For patients without BM, osimertinib + bevacizumab was most likely to rank the first, with cumulative probabilities of 47.1%. For OS, SoC + PbCT was most likely to rank first in patients with and without BM, with cumulative probabilities of 46.8%, and 37.3%, respectively. CONCLUSION: Osimertinib + bevacizumab is most likely to rank first in PFS in advanced EGFR -mutated NSCLC patients with or without BM, and SoC + PbCT is most likely to rank first in OS.

Efficacy of first-line treatments in the elderly and non-elderly patients with advanced epidermal growth factor receptor mutated, non-small cell lung cancer: a network meta-analysis.

OBJECTIVE: Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are the current standard of care for advanced or metastatic non-small cell lung cancer (NSCLC) patients harboring EGFR activating mutations. However, the optimal strategy for elderly NSCLC patients is still under debate. This study was designed to explore the optimal first-line regimens by comparing diverse strategies for elderly and non-elderly EGFR-mutated NSCLC patients. METHODS: A systematic review was conducted to summarize all available randomized controlled trials (RCTs) from PubMed, EMBASE, Cochrane Central Register of Controlled Trials databases, and international conferences before September 30, 2020. The primary outcome was progression free survival (PFS), and the secondary outcome was overall survival (OS). A network meta-analysis (NMA) was constructed using the Bayesian statistical model to synthesize the survival outcomes of all the treatments. RESULTS: In total, 12 RCTs were deemed eligible for inclusion with 3779 patients who have received 10 diverse treatments including EGFR-TKIs. Results from the Bayesian ranking suggested that osimertinib was most likely to rank the first in overall population and in elderly patients in PFS, with the cumulative probabilities of 42.20% and 31.46%, respectively. In non-elderly group (younger than 65 years old), standard of care (SoC, representing first-generation EGFR-TKIs in this NMA) + chemotherapy ranked the first (31.66%). As for OS, SoC + chemotherapy ranked first in all patients (64.33%), patients younger than 65 years old (61.98%), or older than 65 years old (34.45%). CONCLUSION: The regimen of osimertinib is associated with the most favorable PFS in elderly advanced EGFR-mutated NSCLC patients, while SoC + chemotherapy is the optimal strategy in PFS for non-elderly NSCLC patients harboring EGFR activating mutations, and in OS for both elderly and non-elderly EGFR-mutated advanced NSCLC patients. TRIAL REGISTRATION: INPLASY protocol 2020100061 https://doi.org/10.37766/inplasy2020.20.0061 .

Intracranial efficacy of alectinib in ALK-positive NSCLC patients with CNS metastases-a multicenter retrospective study.

BACKGROUND: Central nervous system (CNS) metastases in patients with ALK-positive non-small cell lung cancer (NSCLC) are a cause of substantial morbidity and mortality. Although alectinib had demonstrated promising intracranial efficacy in several clinical trials, data were limited on its CNS activity in real-world settings. METHODS: In this retrospective study, ALK-positive NSCLC patients with brain metastases (BM) or leptomeningeal metastases (LM) from six hospitals in China were divided into three cohorts based on the treatment history before the administration of alectinib. ALK-TKI-naive patients were enrolled in cohort 1, cohort 2 included patients who experienced intracranial progression with or without extracranial progression after treatment with crizotinib, and cohort 3 included patients who developed progression only in CNS following treatment with other second-generation ALK-TKIs. The definition and evaluation of intracranial and extracranial lesions were based on Response Evaluation Criteria in Solid Tumors version 1.1. RESULTS: Sixty-five patients were eligible and included in our study (cohort 1: 20, cohort 2: 32, cohort 3: 13). For the overall population and patients with uncontrolled CNS metastases, similar intracranial response in CNS target lesions was observed: cohort 1: 81.8% and 80%; cohort 2: 76.5% and 86.7%; cohort 3: 42.8% and 33.3%. For patients in these three cohorts, 75% (6/8), 78.6% (11/14), and 83.3% (5/6) were reported to have significant improvement in CNS-related symptoms respectively. The number of patients who were in need of mannitol or corticosteroids decreased remarkably after the treatment of alectinib (p < 0.001), and there was also a steep fall-over in the number of patients with ECOG ≥2 points before and after the administration of alectinib (p = 0.003). All patients (8/8) diagnosed with LM ± BM experienced substantial alleviation in CNS-related symptoms. In cohort 1 and cohort 2, no significant difference in CNS-time to progression was found between patients with symptomatic or asymptomatic BM when treated with alectinib alone. CONCLUSIONS: Our study substantiated the potent CNS activity of alectinib in real-world settings. Patients with symptomatic and asymptomatic BM could benefit from alectinib comparatively, which indicated that alectinib alone might defer the timing of local treatment. However, our results should be treated cautiously owing to limited sample size.

Clinical outcome, long-term survival and tolerability of sequential therapy of first-line crizotinib followed by alectinib in advanced ALK+NSCLC: A multicenter retrospective analysis in China.

BACKGROUND: There is limited data on the clinical outcome, long-term survival and tolerability of sequential therapy of first-line crizotinib followed by alectinib in a real-world setting for Chinese patients with advanced ALK+ NSCLC. METHODS: The medical records of patients who received sequential therapy with first-line crizotinib followed by alectinib (no intermittent systemic therapy was allowed between the two ALK-TKIs) were collected from six centers in China. Combined time treatment to failure (C-TTF) was defined as the period from the start of crizotinib to the complete discontinuation of alectinib due to any cause. RESULTS: A total of 61 patients were included in our study. Fifty-two patients were switched to alectinib due to disease progression, seven as a result of toxicity, and two due to patient preference. At the time of data cutoff, alectinib treatment was discontinued in 31 patients on account of disease progression while severe adverse events resulted in cessation of alectinib in another two patients. Rebiopsy was conducted in 21 patients following disease progression on alectinib in whom ALK secondary mutation was found in 13 patients. Patients with ALK secondary mutation demonstrated better PFS during treatment with subsequent ALK-TKIs compared with those without (10.4 vs. 3.1 m, p = 0.0018, HR = 0.08). With a median follow-up of 34.3 months, C-TTF was 39.2 months and estimated 5-year OS was 68.6% in the overall population. CONCLUSION: Sequential therapy with first-line crizotinib followed by alectinib demonstrated long-term benefits. Different efficacy in subsequent ALK-TKI between patients with or without ALK secondary mutation further emphasized the importance of rebiopsy to guide targeted therapy more precisely.

Alectinib as first-line treatment for advanced ALK-positive non-small cell lung cancer in the real-world setting: preliminary analysis in a Chinese cohort.

Background: Tyrosine kinase inhibitors (TKIs) have been a major advance in the treatment of anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer (NSCLC) which have been substantiated in clinical trials. However, real-world data on first-line alectinib in a Chinese patient population are limited. Methods: We enrolled patients diagnosed with advanced ALK-positive NSCLC treated with first-line alectinib at 8 centers in China, including cases with symptomatic or active CNS metastases. Continuation of alectinib was permitted after local or gradual progression at the treating clinician's discretion. Time-to-treatment failure (TTF) was defined as the period from the start of alectinib to discontinuation for any cause including disease progression, death, adverse events and patient's preference. We defined longer EML4-ALK variants as containing EML4 fusions to at least exon 13 and shorter variants had EML4 fusions up to exon 6. Results: Of the 110 patients included, 26.4% had Eastern Cooperative Oncology Group Performance Status (ECOG) ≥2 points. The objective response rate (ORR) was 88.5% [95% confidence interval (CI): 79.9-94.3%] and median tumor shrinkage rate was 60% (range, 0-100%) in patients with target lesions. For patients with measurable central nervous system (CNS) metastases, the CNS-ORR was 92.9% (95% CI: 66.1-99.8%), additionally, 80% (8/10) of patients experienced significant improvement in CNS-related symptoms following alectinib treatment. With a median follow-up of 18.3 months, the estimated 2-year progression-free survival (PFS) rate and 2-year treatment failure-free rate were 81.1% (95% CI: 71.5-87.7%) and 81.0% (95% CI: 70.6-88.0%) respectively. Grade 3-4 adverse events occurred in 6.4% and only 2 patients (1.8%) permanently discontinued alectinib due to adverse events. Multivariate analysis indicated that patients with metastases in ≥3 distant organs and a tumor reduction rate ≤50% demonstrated more unfavorable mPFS than their counterparts. Furthermore, patients carrying longer variants showed superior mPFS to those with shorter variants (not reached vs. 24.2 months, hazard ratio =0.17, 95% CI: 0.04-0.68, P=0.004). Conclusions: Alectinib showed substantial efficacy and an excellent safety profile in a real-world setting of Chinese patients. Clinical outcomes and long-term survival still require longer follow-up. Tumors with shorter EML4 fusion variants, more extensive metastases and less reduction in tumor lesions may require more aggressive strategies.

Front-Line Therapy in EGFR Exon 19 Deletion and 21 Leu858Arg Mutations in Advanced Non-Small Cell Lung Cancer: A Network Meta-Analysis.

OBJECTIVE: This study aimed to compare the efficacy of different first-line strategies based on different EGFR mutation types (19 deletion and 21 Leu858Arg mutations). METHODS: We conducted a systematic review and network meta-analysis (NMA) by searching and analyzing RCTs on PubMed, Embase, Cochrane Library, ASCO.org, and ESMO.org, from inception to September 30th, 2020. RESULTS: Nineteen RCTs involving 5450 patients were finally included in this study, covering 10 different treatment strategies. The Bayesian ranking results suggested that, in terms of PFS, in the overall population and in patients with 19del mutation, osimertinib was most likely to rank the first, with the cumulative probabilities of 41.89% and 45.73%, respectively, while for patients with 21 Leu858Arg mutation, standard of care (SoC, represents first-generation EGFR-TKIs in this NMA) + chemotherapy was most likely to rank the first, with the cumulative probabilities of 30.81% in PFS. Moreover, SoC + chemotherapy provided the best overall survival benefit for the overall population and patients with 19del, with the cumulative probabilities of 57.85% and 33.51%, respectively. In contrast, for patients with 21 Leu858Arg mutation, dacomitinib showed the most favorable overall survival, with the cumulative probabilities of 36.73%. CONCLUSIONS: In this NMA, osimertinib and SoC combined with chemotherapy would be the optimal first-line treatment options for advanced NSCLC patients harboring EGFR 19 deletion mutation and 21 Leu858Arg mutation, respectively. This finding is likely to be adopted in clinical practice and provide guidance for future clinical study design. Systematic review registration: INPLASY2020100059.

Preparation of chondroitin sulfates with different molecular weights from bovine nasal cartilage and their antioxidant activities.

Biological functions of chondroitin sulfate, including anti-oxidation and anti-inflammation, are associated with its molecular weight. This study aimed to evaluate the correlation between antioxidant activity and molecular weights of chondroitin sulfate derived from bovine nasal cartilage (BCS). BCS extracted by compound enzymatic method was further purified via DEAE-cellulose column separation to obtain BCS-II (129.4 kDa), which was further degraded by H2O2-Vc to obtain four subfractions: BCS-II-1 (92.7 kDa), BCS-II-2 (54.1 kDa), BCS-II-3 (26.3 kDa), and BCS-II-4 (19.7 kDa). Changes in the physicochemical properties of BCS-II before and after degradation were compared via FT-IR, NMR and monosaccharide composition analysis. Finally, antioxidant activities of BCS-II and its subfractions BCS-II-1-4 were compared. Our results showed that the H2O2-Vc system did not disrupt the primary functional group of BCS-II, with no significant change in sulfate content between BCS-II and its degraded fractions; however, uronic acid levels increased in degraded fractions when compared with BCS-II. In vitro, BCS-II-4 displayed the lowest molecular weight and had the strongest antioxidant activity. Therefore, the antioxidant activity of chondroitin sulfate in vitro is robustly associated with its molecular weight, and low-molecular-weight chondroitin sulfate can be used as an antioxidant in the food and pharmaceutical industries and other sectors.

Analysis of the N-Glycoforms and Immunoactivity of Chinese Yam (Dioscorea opposita Thunb.) Glycoprotein 30CYGP.

The major protein in Chinese yam (Dioscorea opposita Thunb.) glycoprotein, 30CYGP, exhibits strong immunomodulatory activities. Research has identified the sequence and structure of 30CYGP; however, 30CYGP N-glycoform composition and immunoactivity remain unknown. We isolated and purified 30CYGP from Chinese yam and used that material to release the N-glycans contained within. The N-glycans were labeled with 1-phenyl-3-methyl-5-pyrazolone and analyzed via ESI-MS and online LC-MS. Additionally, the immunoactivities of 30CYGP and de-glycosylated 30CYGP in the RAW264.7 cell line were investigated. Six 30CYGP N-glycans were observed in total, in which three were modified with xylose (XM: 40%) and three with xylose and fucose (XFM: 60%). Furthermore, de-glycosylated 30CYGP had significantly weaker immunoactivity than 30CYGP. This study demonstrated that novel N-glycoforms may enhance 30CYGP immunoactivity. Further research on the role of varied glycosylation patterns in immunoactivity is needed.

Lycium barbarum polysaccharides extend the mean lifespan of Drosophila melanogaster.

The fruits of Lycium barbarum are considered medicinal foods with high nutritional value and bioactivity. In this study, we aimed to evaluate the effect of a crude L. barbarum polysaccharide (LBP) and two derived fractions, LBP-1 and LBP-2, on the lifespan of Drosophila melanogaster (fruit fly). The average lifespan of fruit flies was extended by supplementing their diet with either of the three LBP preparations. In vivo analysis of antioxidant activities detected increased superoxide dismutase (SOD) and catalase (CAT) activities and decreased malondialdehyde (MDA) levels. Dietary LBP supplements significantly reduced the mortality rate of fruit flies induced by paraquat and hydrogen peroxide. Importantly, the strongest anti-aging activity was exhibited by the LBP-2 fraction, containing arabinogalactan with a molecular weight of 9 × 104 Da. Further studies showed that the anti-aging activity of LBP was, at least in part, mediated by an age-related signaling pathway (MAPK, TOR, S6K) and the expression of longevity genes (Hep, MTH, and Rpn11).

The ammonia-catalyzed release of glycoprotein N-glycans.

Despite the great significance of release and analysis of glycans from glycoproteins, the existing N-glycan release methods are undermined by some limitations and deficiencies. The traditional enzymatic protocols feature high N-glycan release specificity but are generally costly and inefficient for some types of N-glycans. The existing chemical methods require harsh reaction conditions or are accompanied by the remarkable formation of by-products. Herein, we describe a versatile chemical method for the release and analysis of N-glycans from glycoproteins. This method differs from the existing methods as only aqueous ammonia is used to catalyze the N-glycan release reactions. Optimization of reaction conditions was performed using RNase B as a model glycoprotein and the obtained results indicated a highest N-glycan yield in ammonia at 60 °C for 16 h. Comparison of this method with traditional enzymatic protocols and recently reported NaClO methods confirmed the good reliability and efficiency of the novel approach. We also successfully applied this method to some complex biological samples, such as Ginkgo seed protein, fetal bovine serum (FBS) and hen egg white, and demonstrated its great compatibility with various neutral N-glycans, core α-1,3-fucosylated N-glycans and sialylated N-glycans. This method is very simple and cost-effective, enabling convenient analysis and large-scale preparation of released reducing N-glycans from various biological samples for structural and functional glycomics studies.

Physicochemical properties and biological activities of polysaccharides from Lycium barbarum prepared by fractional precipitation.

Traditional separation and purification process of Lycium barbarum polysaccharides (LBP) includes water extraction, alcohol precipitation, deproteinization and ion-exchange column chromatography, which is complicated and time-consuming. In our study, retentate LBP-I and dialysate LBP-O were obtained from LBP by water extraction, alcohol precipitation and deproteinization. LBP-I was separated by fractional precipitation and three fractions (LBP-I-1, LBP-I-2 and LBP-I-3) were obtained. The three fractions were further purified by gel permeation chromatography to LBGP-I-1, LBGP-I-2 and LBGP-I-3 with yields of 0.05%, 0.03%, and 0.19%, respectively, which are higher than yields by traditional method. The physicochemical properties, biological activities of LBGP-I-1, LBGP-I-2 and LBGP-I-3 were investigated. The results indicated that LBGP-I-1 (3.19 × 104 Da) consists of arabinose (21.95%), glucose (51.22%) and galactose (17.07%); LBGP-I-2 (2.92 × 104 Da) mainly consists of arabinose (19.35%), glucose (32.26%) and galactose (35.48%); LBGP-I-3 (9.12 × 104 Da) mainly consists of arabinose (48.15%) and galactose (44.44%). LBGP-I-1 and LBGP-I-2 were different from the components purified by traditional method. LBGP-I-3 could most significantly enhance macrophages NO, phagocytic capacity, and acid phosphatase. LBP-O exhibits the strongest anti-oxidant activities in vitro. These results provided a reference for applications of Lycium barbarum polysaccharides which would benefit the development of industry and agriculture.