0000000000285228

AUTHOR

Armands Sivins

Abstract 4246: Associations of Epstein-Barr virus (EBV)-positive gastric cancer with circulating mediators of inflammation and immune response

Abstract Epstein-Barr virus (EBV) positivity defines one of four major molecular types of gastric cancer in The Cancer Genome Atlas (TCGA). However, viral status is not routinely determined in clinical practice and tumor samples are not generally collected in epidemiologic research. Histologically, EBV-positive gastric cancer is characterized by prominent inflammatory infiltrate. In molecular analyses from TCGA, EBV-positive gastric cancer had significantly higher expression of several chemokines, chemokine receptors and programmed death-ligand 1 (PD-L1) as compared to other molecular types combined. We hypothesized that EBV tumor status may also be reflected in profiles of circulating chem…

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Ex vivo emission of volatile organic compounds from gastric cancer and non-cancerous tissue

The presence of certain volatile organic compounds (VOCs) in the breath of patients with gastric cancer has been reported by a number of research groups; however, the source of these compounds remains controversial. Comparison of VOCs emitted from gastric cancer tissue to those emitted from non-cancerous tissue would help in understanding which of the VOCs are associated with gastric cancer and provide a deeper knowledge on their generation. Gas chromatography with mass spectrometric detection (GC-MS) coupled with head-space needle trap extraction (HS-NTE) as the pre-concentration technique, was used to identify and quantify VOCs released by gastric cancer and non-cancerous tissue samples c…

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SARS-CoV-2 infection and venous thromboembolism after surgery: an international prospective cohort study

SARS-CoV-2 has been associated with an increased rate of venous thromboembolism in critically ill patients. Since surgical patients are already at higher risk of venous thromboembolism than general populations, this study aimed to determine if patients with peri-operative or prior SARS-CoV-2 were at further increased risk of venous thromboembolism. We conducted a planned sub-study and analysis from an international, multicentre, prospective cohort study of elective and emergency patients undergoing surgery during October 2020. Patients from all surgical specialties were included. The primary outcome measure was venous thromboembolism (pulmonary embolism or deep vein thrombosis) within 30 da…

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Associations of epstein-barr virus-positive gastric adenocarcinoma with circulating mediators of inflammation and immune response

Epstein-Barr virus (EBV)-positive gastric adenocarcinoma exhibits locally intense inflammation but systemic manifestations are uncertain. Our study examined whether circulating mediators of inflammation and immune response differ by tumor EBV status. From a Latvian series of 302 gastric cancer cases, we measured plasma levels of 92 immune-related proteins in the 28 patients with EBV-positive tumors and 34 patients with EBV-negative tumors. Eight markers were statistically significantly higher with tumor EBV positivity: chemokine C-C motif ligand (CCL) 20 (Odds Ratio (OR) = 3.6; p-trend = 0.001), chemokine C-X-C motif ligand 9 (OR = 3.6; p-trend = 0.003), programmed death-ligand 1 (PD-L1; OR…

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Modular Point-of-Care Breath Analyzer and Shape Taxonomy-Based Machine Learning for Gastric Cancer Detection

Background: Gastric cancer is one of the deadliest malignant diseases, and the non-invasive screening and diagnostics options for it are limited. In this article, we present a multi-modular device for breath analysis coupled with a machine learning approach for the detection of cancer-specific breath from the shapes of sensor response curves (taxonomies of clusters). Methods: We analyzed the breaths of 54 gastric cancer patients and 85 control group participants. The analysis was carried out using a breath analyzer with gold nanoparticle and metal oxide sensors. The response of the sensors was analyzed on the basis of the curve shapes and other features commonly used for comparison. These f…

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Surgical treatment of gastric cancer in Latvia: Results of centralized experience

Although the mortality for gastric cancer is decreasing in Western Europe and United States, it still remains high in Eastern Europe. This study was aimed at evaluating short- and long-term results of surgical treatment of gastric cancer performed in Latvia Oncology Center.Retrospectively collected data from 461 patients who underwent gastrectomy with curative intent in Latvia Oncology Center from January 2001 to December 2005 were analyzed statistically.An average (range) of 92.2 (81-102) R0-R1 gastrectomies was performed each year. Post-operative complications occurred in 75 patients (16.3%); in-hospital mortality was 3.3%. The overall 5-year survival was 50.8%. In 444 cases (96.3%) there…

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Clinicopathological characteristics of Epstein-Barr virus-positive gastric cancer in Latvia

Objective Epstein-Barr virus (EBV)-associated gastric cancer has been proposed to be a distinct gastric cancer molecular subtype. The prognostic significance of EBV infection in gastric cancer remains unclear and needs further investigation. Our study aimed to analyze EBV-positive and EBV-negative gastric cancer patients regarding their personal and tumor-related characteristics, and compare their overall survival. Methods Gastric cancer patients consecutively treated at the Riga East University Hospital during 2009-2016 were identified retrospectively. Tumor EBV status was determined by in-situ hybridization for EBV-encoded RNA (EBER). Information about clinicopathological characteristics …

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Diagnosis and Classification of 17 Diseases from 1404 Subjects via Pattern Analysis of Exhaled Molecules.

We report on an artificially intelligent nanoarray based on molecularly modified gold nanoparticles and a random network of single-walled carbon nanotubes for noninvasive diagnosis and classification of a number of diseases from exhaled breath. The performance of this artificially intelligent nanoarray was clinically assessed on breath samples collected from 1404 subjects having one of 17 different disease conditions included in the study or having no evidence of any disease (healthy controls). Blind experiments showed that 86% accuracy could be achieved with the artificially intelligent nanoarray, allowing both detection and discrimination between the different disease conditions examined.…

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Breath testing as potential colorectal cancer screening tool

Although colorectal cancer (CRC) screening is included in organized programs of many countries worldwide, there is still a place for better screening tools. In this study, 418 breath samples were collected from 65 patients with CRC, 22 with advanced or nonadvanced adenomas, and 122 control cases. All patients, including the controls, had undergone colonoscopy. The samples were analysed with two different techniques. The first technique relied on gas chromatography coupled with mass spectrometry (GC-MS) for identification and quantification of volatile organic compounds (VOCs). The T-test was used to identify significant VOCs (p values < 0.017). The second technique relied on sensor analysis…

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Analysis of the effects of microbiome-related confounding factors on the reproducibility of the volatolomic test.

Volatile organic compound (VOC) testing in breath has potential in gastric cancer (GC) detection. Our objective was to assess the reproducibility of VOCs in GC, and the effects of conditions modifying gut microbiome on the test results. Ten patients with GC were sampled for VOC over three consecutive days; 17 patients were sampled before and after H. pylori eradication therapy combined with a yeast probiotic; 61 patients were sampled before and after bowel cleansing (interventions affecting the microbiome). The samples were analyzed by: (1) gas chromatography linked to mass spectrometry (GC-MS), applying the non-parametric Wilcoxon test (level of significance p    0.05); (2) by cross-reacti…

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Sensing gastric cancer via point‐of‐care sensor breath analyzer

Background Detection of disease by means of volatile organic compounds from breath samples using sensors is an attractive approach to fast, noninvasive and inexpensive diagnostics. However, these techniques are still limited to applications within the laboratory settings. Here, we report on the development and use of a fast, portable, and IoT-connected point-of-care device (so-called, SniffPhone) to detect and classify gastric cancer to potentially provide new qualitative solutions for cancer screening. Methods A validation study of patients with gastric cancer, patients with high-risk precancerous gastric lesions, and controls was conducted with 2 SniffPhone devices. Linear discriminant an…

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Different Pattern of Inflammatory and Atrophic Changes in the Gastric Mucosa of the Greater and Lesser Curvature.

&#x0D; &#x0D; &#x0D; &#x0D; &#x0D; &#x0D; Background &amp; Aims: Appropriate biopsy sampling is important for the classification of gastritis, yet the extent of inflammation and atrophy of different regions of the stomach with chronic gastritis have been addressed only in a few studies. The aim of our study was to analyze the inflammatory, atrophic and metaplastic changes in the greater and lesser curvature of the antrum and corpus mucosa.&#x0D; Methods: 420 patients undergoing upper endoscopy were enrolled in the study. Four expert gastrointestinal pathologists graded biopsy specimens according to the updated Sydney classification.&#x0D; Results: The obtained results showed that the mononu…

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Detection of precancerous gastric lesions and gastric cancer through exhaled breath.

Timely detection of gastric cancer (GC) and the related precancerous lesions could provide a tool for decreasing both cancer mortality and incidence.968 breath samples were collected from 484 patients (including 99 with GC) for two different analyses. The first sample was analysed by gas chromatography linked to mass spectrometry (GCMS) while applying t test with multiple corrections (p value0.017); the second by cross-reactive nanoarrays combined with pattern recognition. For the latter, 70% of the samples were randomly selected and used in the training set while the remaining 30% constituted the validation set. The operative link on gastric intestinal metaplasia (OLGIM) assessment staging…

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