Application Research Of Extracellular Vesicles MiRNA In Gastrointestinal Cancer

In the panorama of global cancer statistics,liver cancer and stomach cancer stand out with persistently high incidence and mortality rates and they are often diagnosed at intermediate to advanced stages,leading to a notably diminished 5-year survival rate among patients.Current clinical detection methodologies are inadequate in addressing the prevailing challenge,emphasizing the pressing necessity for non-invasive markers facilitating early cancer diagnosis.Research indicates that extracellular vesicles(EVs)facilitate intercellular communication by delivering various bioactive substances through multiple pathways.Among these substances,miRNA constitutes a significant portion of the cargo of EVs.This suggests that EVs miRNA targets may serve as biomarkers for early cancer diagnosis.Nevertheless,prevailing EVs isolation methods commonly exhibit drawbacks such as laborious operation,limited extraction efficiency,and compromised purity and activity.In order to solve these problems,this study introduced a novel,rapid method for the isolation and purification of EVs and EV-derived RNA,accompanied by a proposed set of standards for sample processing and preservation.Building upon this foundation,miRNA profiles within serum EVs from liver and gastric cancer patients across different disease stages were scrutinized,leading to the identification of serum EV miRNA markers with diagnostic value for early liver and gastric cancer,along with their combination into diagnostic models.These findings offer experimental underpinnings for tumor early diagnosis and disease monitoring.Specifically,the research results of this paper are as follows:1.The study pioneered the development of the GlyExo-Capture method,leveraging specific lectins for isolating glycosylated EVs from samples.By employing plant lectins for affinity separation of specific sugar chains on EVs surfaces,this method prioritized tumor specificity over size specificity,thereby capturing vesicles of varying sizes while preserving their intact structure and activity.The method’s expedited processing and high throughput signified a significant advancement in EVs extraction techniques,thereby facilitating clinical application.2.This study evaluated the preservation and handling standards for blood samples used to isolate EVs using the GlyExo-Capture method.Reference conditions were established to ensure the integrity and reliability of samples during collection,transportation,and storage,ensuring the reliability of glycosylated EV miRNA extracted from blood samples in clinical practice3.This study presented the development of a high-throughput automated EV RNA extraction method based on magnetic beads.The method offered high extraction efficiency,simplicity,cost-effectiveness,low DNA contamination,and safety.Optimization of automated RNA extraction focused on four aspects: lysis,magnetic beads,washing,and elution,with an emphasis on miRNA enrichment within RNA.The method demonstrated applicability across different sample types and EVs isolation methodologies.4.Utilizing the independently developed GlyExo-Capture method,this study conducted screening for early diagnostic markers of liver cancer.A predictive model comprising 3 miRNA target pairs for liver cancer was constructed and evaluated across multiple independent sample sets.Integration of model features with alpha-fetoprotein(AFP)yielded a more effective predictive model.Additionally,the AFP and miRNA models exhibited complementary characteristics,reducing false-negative results.Various clinical parameters were also incorporated to comprehensively explore the clinical applicability of the model.5.Leveraging the independently developed GlyExo-Capture method,this study conducted screening for early diagnostic markers of gastric cancer.Markers were identified through screening in discovery cohorts of gastric cancer patients and controls,culminating in the construction of a diagnostic model comprising 5 miRNA target pairs.In an independent validation cohort,the diagnostic model displayed notable sensitivity and specificity in discriminating between patients afflicted with gastric cancer and those without the condition,with notable performance in identifying neural invasion and lymph node metastasis.These findings provided robust support for liquid biopsy as a non-invasive cancer diagnostic tool.