Evaluating treatment monitoring in coloncancer patients using short repetitive sequences of ALU-(Alu sequences) based serum cfDNA and the expression ofserum onco-piRNAs

Background: Colorectal cancer (CRC) is the second mainspringof cancer and cancer-related mortality globally. Theincidence and mortality rates are increasing year by year andseriously endangering people’s health. Liquid biopsy is a newtechnology to detect tumor-related molecular markers in specimensby analyzing CTCs, ctDNA, circulating free (cfDNA) orRNA, and exosomes. Also, studies have suggested that piwiinteractingRNAs (piRNAs), a new type of non-coding RNA(ncRNA), are closely related to the occurrence and developmentof cancer and monitoring chemotherapy in CRC. The extentto which, serum piRNA and cfDNA levels can be used forCRC treatment remains will be evaluated.Materials and Methods: In a cross-sectional study, ۵۰ newlydiagnosed CRC patients with different TNM stages (Ⅰ, Ⅱ, Ⅲ,Ⅳ) who are candidates for surgery or chemotherapy will beincluded in the study. in silico analyzed novel piRNAs and AlubasedcfDNA levels in the serum – that are specific fragments۱۱۵bp and ۲۴۷bp and increased in CRC (Alu۱۱۵/۲۴۷) assessed.In baseline (before treatment) ۱۰ ml of whole blood (liquidbiopsy) will be collected from the patients. Following plasmaisolation, RNA and cfDNA isolation performed from plasma fraction. These isolations have done by specific isolation kits.After designing specific primers for piRNA, and Alu fragments,(qPCR) performed. The expression level of piRNAs and serumamount of Alu۱۱۵/۲۴۷ analyzed. For treatment monitoring, atthe end of treatment (EOT; after ۶ months treatment) ۱۰ ml ofwhole blood taken from the patient, and the expression level ofstudied piRNA and Alu۱۱۵/۲۴۷ levels evaluated too. Clinicaland pathological characteristics of patients including, differentiationstatus (good, moderate, poor, and others), and diseasestage based on TNM (StageI-II StageIII-IV) compared withthose expression levels.Results: According to the previous studies and our data indiceswere increased before the treatment After the treatment, theirexpression should be reduced for this purpose as a biomarkerfor monitoring the treatment can be usedConclusion: The majority of cases (about ۷۰%) of colorectalcancer (CRC) are diagnosed in advanced stages of RNANon-coding and cfDNA have great effects on CRC response totreatment. Analysis of circulating cell-free DNA levels (cfDNA)is an important tool for monitoring cancer. Also, the relationshipbetween the quality of response to treatment and thelevel of expression piRNAs and miRNAs in the managementof CRC patients can provide a new perspective for doctors andscientists.

کلیدواژه ها:

Prognosis ، Biomarkers ، Non-coding RNAs ، piRNA