Aptamer-based biosensors: a novel toolkit for early diagnosis of cancer

Cancer is one of the leading causes of death if not detected at an early stage. Early diagnosis of cancer is a real challenge because of its multifactorial, asymptomatic, and misleading diagnosis. Subject to early diagnosis, cancer can be treated using an appropriate approach. Until now, different biomarkers have been designed and used for the early diagnosis of cancer. Vascular endothelial growth factor (VEGF) is one of the common and potential targets for the prognosis of different types of cancer. Previous research showed that a different number of microRNAs (miRNAs) regulates VEGF in cancer microenvironment. The miRNA expression is either upregulated or downregulated in cancer progression. To tackle such challenging issues, aptamers have been widely used in therapeutics and diagnostic modalities. Aptamers are small oligos and currently used as biosensors because of its specificity and binding affinity to low molecular weight molecules. Herein, we reviewed various compatible modifications that have been introduced to increase the efficiency and specificity of aptamers for early cancer diagnosis by detection of miRNAs expression. (C) 2019 Elsevier Ltd. All rights reserved.