microRNA Detection via Nanostructured Biochips for Early Cancer Diagnostics

Abstract

MicroRNA (miRNA) are constituted of approximately 22 nucleotides and play an important role in the regulation of many physiological functions and diseases. In the last 10 years, an increasing interest has been recorded in studying the expression profile of miRNAs in cancer. Real time-quantitative polymerase chain reaction (RT-qPCR), microarrays, and small RNA sequencing represent the gold standard techniques used in the last 30 years as detection methods. The advent of nanotechnology has allowed the fabrication of nanostructured biosensors which are widely exploited in the diagnostic field. Nanostructured biosensors offer many advantages: (i) their small size allows the construction of portable, wearable, and low-cost products; (ii) the large surface–volume ratio enables the loading of a great number of biorecognition elements (e.g., probes, receptors); and (iii) direct contact of the recognition element with the analyte increases the sensitivity and specificity inducing low limits of detection (LOD). In this review, the role of nanostructured biosensors in miRNA detection is explored, focusing on electrochemical and optical sensing. In particular, four types of nanomaterials (metallic nanoparticles, graphene oxide, quantum dots, and nanostructured polymers) are reported for both detection strategies with the aim to show their distinct properties and applications.

The Role of microRNAs in Epigenetic Regulation of Signaling Pathways in Neurological Pathologies

“…Biosensor [ 33 ] and microarray [ 34 ] methods are known for hybridizing microRNAs, enabling the simultaneous detection of a large number (hundreds or thousands) of microRNA targets. High-throughput sequencing (Sanger sequencing or next-generation sequencing) [ 35 ] is used to identify new microRNA sequences.…”

Hypermethylated TAGMe as a universal-cancer-only methylation marker and its application in diagnosis and recurrence monitoring of urothelial carcinoma

“…Early diagnosis of cancer has been an area of high-profile research. Emerging cancer detection technologies based on more accurate biomedical imaging [ 1 – 4 ], DNA mutation [ 5 ], epigenetic abnormality [ 6 , 7 ], or metabolic products [ 8 ] have been developed and evaluated. Of these, DNA methylation aberration of specific genes occurs during the cancerous initiation and multiple progression stages, which has been considered as promising targets for the development of powerful diagnostic, prognostic, and predictive biomarkers [ 9 – 11 ].…”

Identification and bioinformatic characterization of a serum miRNA signature for early detection of laryngeal squamous cell carcinoma

“…Circulating miRNAs have many of the essential characteristics of good biomarkers: they are stable in circulation, resistant to RNase digestion, extreme pH, high temperatures, prolonged storage and multiple freeze–thaw cycles [ 25 , 26 ]. Moreover, circulating miRNA represent an excellent target for the nanostructured biosensors increasingly developed and exploited in the diagnostic field [ 27 ]. Nevertheless, the clinical efficacy of miRNAs as circulating biomarkers can be affected by a number of variables such as sample collection and processing, RNA extraction efficiency, as well as other technical aspects involved in the success of qRT-PCR and data analysis; however, correct operations are strictly required in order to increase sensitivity and to obtain reliable results [ 28 ].…”