Screening of Serum Exosomal miRNAs as Diagnostic Biomarkers for Gastric Cancer Using Small RNA Sequencing

Abstract

Background/Aim. Exosomal miRNAs are promising tumor biomarkers. This research explored the diagnostic value of serum exosomal miRNAs by analyzing the exosomal miRNAs derived from the serum of gastric cancer patients. Methods. Deep sequencing of exosomal miRNAs was performed using an Illumina HiSeq2500 sequencer on serum samples from three healthy subjects in the normal control group (group N) and six gastric cancer patients in the gastric cancer treatment group (group T). Bioinformatics analysis was performed on exosomal miRNA profiles to screen differentially expressed miRNA. In addition, target gene prediction, GO, and KEGG pathway enrichment analyses were performed. Finally, the serum exocrine bodies of 24 patients with gastric cancer and 24 normal controls were verified by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) to confirm the findings. The receiver operating characteristic (ROC) curve of the subjects was plotted, and the area under the curve (AUC) was calculated with a 95% confidence interval (CI). Results. The exosomes were successfully extracted from the serum of gastric cancer patients, which showed a form of goblet vesicles or irregular circles, with an average particle size of approximately 102.3 nm. The exosomal marker proteins, CD9, CD63, TSG101, and calnexin, were positively expressed. Small RNA sequencing detected 15 different types of RNA components in the serum exosomes, and the most abundant one was miRNA. In the screened cohort, the downregulation of seven existing miRNAs and the upregulation of one existing miRNA were observed. Four of them were selected for confirmation, revealing that the expression of miR-10401-3p, miR-1255b-5p, and miR-6736-5p declined significantly in group T ( P < 0.05 ). In addition, the ROC curve showed that the AUC values for these three miRNAs were 0.8333, 0.8316, and 0.8142, respectively; all of them are statistically significant ( P < 0.05 ). Conclusions. The above three miRNAs found in the serum exosomes from gastric cancer patients might serve as diagnostic biomarkers for gastric cancer.

Extracellular vesicle biomarkers in circulation for the diagnosis of gastric cancer: A systematic review and meta‑analysis

“…The mean sample size of groups of patients with GC was 98 (range, 23-386 patients), whereas the mean sample size of the control groups was 62 (range, 12-151 patients). A total of 26 studies analyzed the diagnostic value of RNAs for GC: MiRNAs in 13 studies (22,24,25,(28)(29)(30)(31)(32)(33)37,40,42,44,45), four of which performed validation tests (25,29,31,44); lncRNAs in nine studies (19,20,23,26,35,38,39,41,45); circular RNAs (circRNAs) in three studies (21,27,34); P-element induced wimpy testis-interacting RNAs (piRNAs) in one study (42); mRNA in one study (43); and a single study reported the diagnostic value of protein (36). A total of nine studies set a diagnostic cut-off value, which was determined using the Youden Index (19,23,27,31,33,34,39,41,45).…”

Exosome RNA Sequencing as a Tool in the Search for Cancer Biomarkers

“…It was then discovered that the expression of miR-10401-3p, miR-1255b-5p, and miR-6736-5p in serum exosomes from GC patients was considerably lower than in serum exosomes from healthy people. Taken together, these data show that exosomal miR-10401-3p, miR-1255b-5p, and miR-6736-5p could be used as diagnostic biomarkers for GC [ 92 ]. Zhang et al also applied small RNA sequencing to uncover differentially regulated miRNAs using exosomes isolated from GC patient plasma as well as from healthy subjects.…”

Four differentially expressed exosomal miRNAs as prognostic biomarkers and therapy targets in endometrial cancer: Bioinformatic analysis

“…Because of the heterogeneity of cancer cells, exosomal miRNAs from host cancer cells can activate the receptors or change miRNA or RNA expression in the neighboring cancer cells to alter their biological phenotypes. [12] Numerous publications present various exosomal miRNAs as potential biomarkers of breast cancer, [20] lung cancer, [21][22][23][24] gastric cancer, [25][26][27][28] colorectal cancer, [29][30][31][32] EC, [33] epithelial ovarian cancer, [34] and other cancers. [35][36][37][38][39][40][41][42][43][44][45] Here, as reported by Srivastava A etc, exosomes with a unique miRNA signature can be isolated from the urine of symptomatic women who are diagnosed with EC.…”