257Alfred K. Lam (ed.), Esophageal Adenocarcinoma: Methods and Protocols, Methods in Molecular Biology, vol. 1756,
https://doi.org/10.1007/978-1-4939-7734-5_22, © Springer Science+Business Media, LLC 2018
Chapter 22
Detection and Quantification of MicroRNAs in Esophageal
Adenocarcinoma
Moein Amin, Farhadul Islam, Vinod Gopalan, and Alfred K. Lam
Abstract
MicroRNAs (miRNAs) are a class of small, noncoding RNAs that have been emerging as novel regulators
in esophageal adenocarcinoma. Their role has been established in various aspects of esophageal adenocar-
cinoma including carcinogenesis, progression, treatment, and prognosis. Therefore, miRNA detection,
profiling, and quantification have become extremely important for scientists and clinicians. As miRNAs are
small, their detection can be challenging. There have been various methods developed to detect and/or
quantify miRNAs. This chapter aims to introduce the fundamentals and methods of the most commonly
used approaches including miRNA microarrays and quantitative real-time polymerase chain reaction
(RT-qPCR) to detect and quantify miRNAs in esophageal adenocarcinoma.
Key words MiRNA, Esophageal adenocarcinoma, Microarray, Northern blotting, RT-qPCR1 Introduction
MicroRNAs (miRNAs) are small (length from 18–25 nt) noncod-
ing single-stranded RNAs that regulate expression of complemen-
tary messenger RNAs and play a significant role in diverse
physiological and pathological pathways [ 1 ]. They have crucial
roles in cancer as miRNAs can control cell proliferation, stem cell
regulation, apoptosis, invasion/metastasis, and angiogenesis to
affect tumor development by modulating the expression of their
targets [ 2 – 12 ]. Altered miRNA levels have shown to be associated
with diagnosis, staging, progression, prognosis, and response to
treatment in many human cancers [ 2 – 12 ].
Esophageal cancer is one of the most common cancers world-
wide and adenocarcinoma subtype is the most common subtype in
western countries [ 13 ]. Many miRNAs have been shown to cor-
respond with the clinical and pathological characteristics of esoph-
ageal adenocarcinoma [ 14 ].
MiR-196, miR-192, and miR-21 are frequently upregulated,
whereas miR-let-7 is often downregulated in a stepwise fashion