Tetraspanins and miRNAs in urinary extracellular vesicles in patients with colonic polyps and a family history of colorectal cancer

<title>Abstract</title> Introduction: Urinary microRNAs (miRNAs) and extracellular vesicles (EVs) may serve as useful biomarkers for neoplastic (CRC) or preneoplastic colorectal lesions. Patients and methods: A prospective observational study was conducted on individuals with first-degree family relatives (FDR) of colorectal cancer (CRC) and a control group. Flow cytometry (FC) and next-generation sequencing were used to study the profile of tetraspanins and miRNAs carried by EVs in urine samples. Results: A total of 46 individuals were included (mean age 53.52 ±7.71 years). Of these, 69.39% had a FDR CRC (group 1: 20 patients with hyperplastic polyps or no polyps, and group 2: 11 with adenomas). Fifteen individuals (group 3: controls) had neither FDR CRC nor polyps. Eighteen urine samples were analyzed. Two miRNAs (miR-141-3p and miR-30d-5p) were differentially expressed (p&lt;0.05) in subjects with CRC FDR compared to controls. The tetraspanin profile (CD9, CD63, and CD81) of subjects with FDR CRC differed from that of controls. Quantitative PCR analysis confirmed the differences found in next-generation sequencing when comparing all groups. Conclusions: The tetraspanin profile of individuals with FDR CRC differs from that of controls. This allows for the hypothesis that certain tetraspanins may serve as "biomarker of biomarkers." On the other hand, next-generation sequencing of miRNAs present in urinary EV samples enables the identification of their expression levels, thus representing a valid and non-invasive method for studying and monitoring their expression in different groups.