Clinical proteomics identifies potential biomarkers in Helicobacter pylori for gastrointestinal diseases

Transcatheter arterial chemoembolisation combined with lenvatinib and cabozantinib in the treatment of advanced hepatocellular carcinoma

OBJECTIVE

The objective of this study was to evaluate the effect and prognosis of transcatheter arterial chemoembolisation (TACE) combined with lenvatinib and cabozantinib in the treatment of advanced unresectable hepatocellular carcinoma (uHCC) and identify the predictors of prognosis related to cellular inflammation and body mass index (BMI). To the best of our knowledge, this is the first study to report the efficacy and prognosis of TACE combined with lenvatinib and cabozantinib in patients with uHCC and propose the neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) as predictors of response and survival outcomes in this context.

METHODS

The clinicopathologic data of 217 patients with advanced uHCC who underwent TACE combined with systemic therapy (lenvatinib mesylate + cabozantinib) in the Department of Hepatobiliary Surgery, Dazhou Central Hospital between October 2017 and February 2020 were collected retrospectively, and the relevant parameters were analysed and compared.

RESULTS

Univariate and multivariate logistic regression analyses showed that BMI, NLR, PLR and prothrombin time were independent factors for the objective response rate (ORR) of transformed therapy for uHCC (OR = 0.812 vs 1,290.68 vs 1.067 vs 0.626, 95 % CI: 0.719-0.897 vs 108.081-11,541.137 vs 1.037-1.099 vs 0.414-0.946, respectively, p < 0.05). The results showed that BMI, NLR and PLR had certain predictive values for the ORR in patients with liver cancer undergoing translational therapy (p < 0.05); the combined predictive effect of the three was the best, and the area under the curve (AUC) of BMI + NLR + PLR for predicting the ORR in patients with liver cancer undergoing translational therapy was 0.951 (95 % CI: 0.921, 0.964). A total of 181 patients experienced adverse reactions at different grades, including 104 cases at grade 1, 50 cases at grade 2, 22 cases at grade 3 and 5 cases at grade 4. There was a significant difference in overall survival (OS) between low- and high-NLR groups, low- and high-PLR groups and low- and high-BMI groups (χ2 = 9.644, 8.313 and 10.314, respectively, p < 0.05). There was a significant difference in progression-free survival (PFS) between the low- and high-NLR groups, the low- and high-PLR groups and the low- and high-BMI groups (χ2 = 8.965, 9.783 and 6.343, respectively, p < 0.05).

CONCLUSION

Transcatheter arterial chemoembolisation combined with lenvatinib and cabozantinib is safe and effective in the treatment of advanced uHCC, with controllable adverse reactions. High NLR and PLR and low BMI values before treatment were independent risk factors for the ORR. Body mass index, NLR and PLR predicted responses to triple switch therapy and survival outcomes in uHCC. Patients with pretreatment NLR ≥ 2.96 and PLR ≥ 184.41 had worse OS and PFS rates. Patients with pretreatment BMI ≥ 23 kg/m2 had improved OS and a reduced risk of death.

Reactive oxygen species and gastric carcinogenesis: The complex interaction between Helicobacter pylori and host

Helicobacter pylori (H. pylori) is a highly successful human pathogen that colonizes stomach in around 50% of the global population. The colonization of bacterium induces an inflammatory response and a substantial rise in the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), mostly derived from host neutrophils and gastric epithelial cells, which play a crucial role in combating bacterial infections. However, H. pylori has developed various strategies to quench the deleterious effects of ROS, including the production of antioxidant enzymes, antioxidant proteins as well as blocking the generation of oxidants. The host's inability to eliminate H. pylori infection results in persistent ROS production. Notably, excessive ROS can disrupt the intracellular signal transduction and biological processes of the host, incurring chronic inflammation and cellular damage, such as DNA damage, lipid peroxidation, and protein oxidation. Markedly, the sustained inflammatory response and oxidative stress during H. pylori infection are major risk factor for gastric carcinogenesis. In this context, we summarize the literature on H. pylori infection-induced ROS production, the strategies used by H. pylori to counteract the host response, and subsequent host damage and gastric carcinogenesis.

Effects of Carbon Quantum Dots on Aquatic Environments: Comparison of Toxicity to Organisms at Different Trophic Levels

Carbon quantum dots (CQDs) have high hydrophilicity, high cell permeability, and are frequently used in water-based and biorelated applications, yet studies concerning the ecological risks of CQDs in aquatic environments are largely insufficient. In the present study, the toxicity of CQDs to zebrafish ( Danio rerio), zooplankton ( Daphnia magna), and phytoplankton ( Scenedesmus obliquus) were assessed for the first time. The results indicated that CQDs (up to 200 mg/L) could be depurated by D. rerio with negligible toxicity. In comparison, CQDs induced mortality and immobility in D. magna with a 48-h EC₅₀ value and LC₅₀ value of 97.5 and 160.3 mg/L, respectively. In S. obliquus, CQDs inhibited photosynthesis and nutrition absorption in a dose- and time-dependent manner, and the growth of algae was also inhibited with a 96-h EC₅₀ value of 74.8 mg/L, suggesting that S. obliquus, the lowest trophic level in this study, was most sensitive to CQDs exposure. Further investigations revealed that CQDs induced an increase in oxidative stress in algae cells and a decrease in pH value of an algae medium, indicating that oxidative stress and water acidification may be the mechanisms underlying the toxicity of CQDs to S. obliquus.

Diminished circulating concentration of interleukin-35 in Helicobacter pylori-infected patients with peptic ulcer: Its association with FOXP3 gene polymorphism, bacterial virulence factor CagA, and gender of patients

BACKGROUND

IL-35 modulates immune and inflammatory responses during infections. Here, we investigated IL-35 levels and a single nucleotide polymorphism, rs3761548, in FOXP3 gene in Helicobacter pylori-infected patients with peptic ulcer (PU), to clarify possible associations.

MATERIALS AND METHODS

This study includes 100 H. pylori-infected PU patients, 100 H. pylori-infected asymptomatic subjects (AS), and 100 noninfected healthy subjects (NHSs). Serum IL-35 levels and the genotyping were determined using ELISA and RFLP-PCR methods, respectively.

RESULTS

In PU patients, the IL-35 levels were lower than AS and NHS groups (P < .001). The IL-35 levels in CagA⁺ H. pylori-infected participants from PU and AS groups were lower than individuals infected with CagA^- strains (P < .02 and P < .04, respectively). Women had higher IL-35 levels than men among PU, AS, and NHS groups (P < .0001). In PU patients, AA genotype and A allele at rs3761548 were more frequent than total healthy subjects (AS + NHS groups) and associated with an increased PU risk (AA genotype: OR = 5.51, P < .0001; A allele: OR = 3.857, P < .002). In PU and AS groups, IL-35 levels were lower in subjects displaying AA genotype or A allele than subjects displaying CC genotype or C allele, respectively (P < .0001 and P < .03 for PU patients; P < .001 and P < .02 for AS group, respectively).

CONCLUSIONS

Decreased IL-35 levels could be involved in PU development in H. pylori-infected individuals. IL-35 levels are affected by CagA status of H. pylori, participants gender, and genetic variations at rs3761548. The AA genotype and A allele at rs3761548 could represent a risk factor for PU development.

Preprocessing of 2-Dimensional Gel Electrophoresis Images Applied to Proteomic Analysis: A Review

Various methods and specialized software programs are available for processing two-dimensional gel electrophoresis (2-DGE) images. However, due to the anomalies present in these images, a reliable, automated, and highly reproducible system for 2-DGE image analysis has still not been achieved. The most common anomalies found in 2-DGE images include vertical and horizontal streaking, fuzzy spots, and background noise, which greatly complicate computational analysis. In this paper, we review the preprocessing techniques applied to 2-DGE images for noise reduction, intensity normalization, and background correction. We also present a quantitative comparison of non-linear filtering techniques applied to synthetic gel images, through analyzing the performance of the filters under specific conditions. Synthetic proteins were modeled into a two-dimensional Gaussian distribution with adjustable parameters for changing the size, intensity, and degradation. Three types of noise were added to the images: Gaussian, Rayleigh, and exponential, with signal-to-noise ratios (SNRs) ranging 8-20 decibels (dB). We compared the performance of wavelet, contourlet, total variation (TV), and wavelet-total variation (WTTV) techniques using parameters SNR and spot efficiency. In terms of spot efficiency, contourlet and TV were more sensitive to noise than wavelet and WTTV. Wavelet worked the best for images with SNR ranging 10-20 dB, whereas WTTV performed better with high noise levels. Wavelet also presented the best performance with any level of Gaussian noise and low levels (20-14 dB) of Rayleigh and exponential noise in terms of SNR. Finally, the performance of the non-linear filtering techniques was evaluated using a real 2-DGE image with previously identified proteins marked. Wavelet achieved the best detection rate for the real image.

Mechanisms underlying the acute toxicity of fullerene to Daphnia magna: Energy acquisition restriction and oxidative stress

The toxicity of fullerene (C₆₀) to Daphnia magna has been a subject with increasing concerns. Nevertheless, the underlying mechanisms are still poorly understood. In the present study, we evaluated various aspects of the toxicological impacts of C₆₀ on daphnia. After a 72-h exposure, the 50% effective concentration of C₆₀ was 14.9 mg/L for immobilization, and 16.3 mg/L for mortality. Daphnia exhibited a quick uptake of C₆₀ with a body burden value of 413 μg/g in wet weight in the 1 mg/L C₆₀ treatment group. Transmission electron microscopy observations revealed that C₆₀ had mainly accumulated in the guts of organisms. The feeding rate, gut ultra-structural alterations, and digestive enzyme activities of daphnia in response to C₆₀ treatment were evaluated. The results revealed a significant reduction in the digestion and filtration rates, as well as gut impairment and inhibition of digestive enzymes (cellulose, amylase, trypsin, and β-galactosidase) activity of C₆₀ exposed daphnia. In addition, the changes in superoxide dismutase (SOD) and malondialdehyde (MDA) levels in daphnia under C₆₀ exposures were also discovered. These results, for the first time, provide systematic evidence that C₆₀ caused a restriction in energy acquisition and increased oxidative damage in daphnia, which might be related to the bioaccumulation of C₆₀ and finally led to the immobility and mortality.

Helicobacter pylori infection perturbs iron homeostasis in gastric epithelial cells

The iron deficiency anaemia that often accompanies infection with Helicobacter pylori may reflect increased uptake of iron into gastric epithelial cells. Here we show an infection-associated increase in total intracellular iron levels was associated with the redistribution of the transferrin receptor from the cell cytosol to the cell surface, and with increased levels of ferritin, an intracellular iron storage protein that corresponded with a significant increase in lysosomal stores of labile iron. In contrast, the pool of cytosolic labile iron was significantly decreased in infected cells. These changes in intracellular iron distribution were associated with the uptake and trafficking of H. pylori through the cells, and enhanced in strains capable of expressing the cagA virulence gene. We speculate that degradation of lysosomal ferritin may facilitate H. pylori pathogenesis, in addition to contributing to bacterial persistence in the human stomach.

Application of proteomics to the study of Helicobacter pylori and implications for the clinic

INTRODUCTION

Helicobacter pylori (H. pylori) is a gram-negative bacterium that colonizes the gastric epithelium and mucous layer of more than half the world's population. H. pylori is a primary human pathogen, responsible for the development of chronic gastritis, peptic ulceration and gastric cancer. Proteomics is impacting several aspects of medical research: understanding the molecular basis of infection and disease manifestation, identification of therapeutic targets and discovery of clinically relevant biomarkers. Areas covered: The main aim of the present review is to provide a comprehensive overview of the contribution of proteomics to the study of H. pylori infection pathophysiology. In particular, we focused on the role of the bacterium and its most important virulence factor, CagA, in the progression of gastric cells transformation and cancer progression. We also discussed the proteomic approaches aimed at the investigation of the host response to bacterial infection. Expert commentary: In the field of proteomics of H. pylori, comprehensive analysis of clinically relevant proteins (functional proteomics) rather than entire proteomes will result in important medical outcomes. Finally, we provided an outlook on the potential development of proteomics in H. pylori research.

Combination of OipA, BabA, and SabA as candidate biomarkers for predicting Helicobacter pylori-related gastric cancer

Helicobacter pylori (H. pylori ) infection is a major cause of chronic gastritis and is highly related to duodenal ulcer (DU) and gastric cancer (GC). To identify H. pylori-related GC biomarkers with high seropositivity in GC patients, differences in levels of protein expression between H. pylori from GC and DU patients were analyzed by isobaric tag for relative and absolute quantitation (iTRAQ). In total, 99 proteins showed increased expression (>1.5-fold) in GC patients compared to DU patients, and 40 of these proteins were categorized by KEGG pathway. The four human disease-related adhesin identified, AlpA, OipA, BabA, and SabA, were potential GC-related antigens, with a higher seropositivity in GC patients (n = 76) than in non-GC patients (n = 100). Discrimination between GC and non-GC patients was improved using multiple antigens, with an odds ratio of 9.16 (95% CI, 2.99-28.07; p < 0.0001) for three antigens recognized. The optimized combination of OipA, BabA, and SabA gave a 77.3% correct prediction rate. A GC-related protein microarray was further developed using these antigens. The combination of OipA, BabA, and SabA showed significant improvement in the diagnostic accuracy and the protein microarray containing above antigens should provide a rapid and convenient diagnosis of H. pylori-associated GC.

DBGC: A Database of Human Gastric Cancer

The Database of Human Gastric Cancer (DBGC) is a comprehensive database that integrates various human gastric cancer-related data resources. Human gastric cancer-related transcriptomics projects, proteomics projects, mutations, biomarkers and drug-sensitive genes from different sources were collected and unified in this database. Moreover, epidemiological statistics of gastric cancer patients in China and clinicopathological information annotated with gastric cancer cases were also integrated into the DBGC. We believe that this database will greatly facilitate research regarding human gastric cancer in many fields. DBGC is freely available at http://bminfor.tongji.edu.cn/dbgc/index.do

Clinical proteomics identifies urinary CD14 as a potential biomarker for diagnosis of stable coronary artery disease

Inflammation plays a key role in coronary artery disease (CAD) and other manifestations of atherosclerosis. Recently, urinary proteins were found to be useful markers for reflecting inflammation status of different organs. To identify potential biomarker for diagnosis of CAD, we performed one-dimensional SDS-gel electrophoresis followed by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Among the proteins differentially expressed in urine samples, monocyte antigen CD14 was found to be consistently expressed in higher amounts in the CAD patients as compared to normal controls. Using enzyme-linked immunosorbent assays to analyze the concentrations of CD14 in urine and serum, we confirmed that urinary CD14 levels were significantly higher in patients (n = 73) with multi-vessel and single vessel CAD than in normal control (n = 35) (P < 0.001). Logistic regression analysis further showed that urinary CD14 concentration level is associated with severity or number of diseased vessels and SYNTAX score after adjustment for potential confounders. Concomitantly, the proportion of CD14+ monocytes was significantly increased in CAD patients (59.7 ± 3.6%) as compared with healthy controls (14.9 ± 2.1%) (P < 0.001), implicating that a high level of urinary CD14 may be potentially involved in mechanism(s) leading to CAD pathogenesis. By performing shotgun proteomics, we further revealed that CD14-associated inflammatory response networks may play an essential role in CAD. In conclusion, the current study has demonstrated that release of CD14 in urine coupled with more CD14+ monocytes in CAD patients is significantly correlated with severity of CAD, pointing to the potential application of urinary CD14 as a novel noninvasive biomarker for large-scale diagnostic screening of susceptible CAD patients.