A Summary of the Main Biomarkers for Diagnosis and Prognosis of Sporadic Colorectal Cancer: A Review

Abstract

Sporadic colorectal cancer (SCRC) affects regions of the large intestine (colon) and rectum that are not of family origin. The carcinogenesis process involves the interaction between environmental and genetic factors. This tumor is characterized by intestinal obstruction, bleeding (hematochezia, enterorrhagia), an altered bowel habit, and systemic conditions, such as weight loss. Some risk factors for SCRC are age over 60 years, a diet with high saturated fat, red meat, alcohol consumption, and smoking. An early diagnosis is essential for effective patient treatment and survival. Finding more effective and less invasive tumor, such as biomarkers, are important for ensuring that people participate in cancer screenings. Some studies have evaluated molecular biomarkers, such as micro ribonucleic acids (microRNAs, or miRNAs) and genes, in relation to the pathways leading to SCRC carcinogenesis, and it has been found that many of these biomarkers are highly expressed in this type of tumor. This review shows data from the literature search in PubMed in the period from January 2017 to April 2018 focusing news biomarkers in SCRC, including microsatellite instability, genes, and micro ribonucleic acids (micro RNAs, or miRNAs), associated with diagnosis, prognosis, and treatment in blood, tissue and feces samples. Thus, this literature review shows that microsatellite instability and gene markers have been extensively studied and characterized as biomarkers in the diagnosis, prognosis, and treatment of SCRC. In addition, some miRNAs have been demonstrated as good noninvasive biomarkers in stool and plasma samples.