Research Paper|Volume 12, Issue 1|pp 808—824

Low-abundance mutations in colorectal cancer patients and healthy adults

Yanfei Li^1,², Zhengsheng Dai³, Gang Huang⁴, Yueling Jin⁴, Zhongping Ning¹, Junwei Shen^1,⁵

¹Shanghai University of Medicine and Health Sciences Affiliated Zhoupu Hospital, Shanghai, China
²School of Medical Technology, Shanghai University of Medicine and Health Sciences, Shanghai, China
³Shanghai Pudong Hospital Affiliated to Fudan University, Shanghai, China
⁴Shanghai University of Medicine and Health Sciences, Shanghai, China
⁵Tongji University Affiliated Eastern Hospital, Shanghai, China

Received: September 7, 2019Accepted: December 24, 2019Published: January 12, 2020

Copyright: © 2020 Li et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Detecting low-abundance mutations is very important for cancer diagnosis and treatment. Here we describe an improved targeted sequencing analysis that dramatically increases sequencing depth. Seven colorectal cancer (CRC) patients and seven healthy adults were enrolled in this study. We examined genetic mutations in tissue samples from the central and peripheral regions of tumors from the CRC patients and in blood cells from the healthy adults. We observed that each CRC carried larger numbers of mutations more than previously estimated. These included numerous deletion mutations in the tumor tissue. While the cellular morphology in the surrounding normal colonic tissues was healthy, these cells also carried many mutations. Similarly, the blood cells from the healthy donors carried numerous mutations. These findings shed new light on the processes of tumorigenesis and aging, and also present a potentially effective method for detecting low-abundance mutations for cancer diagnosis and targeted treatments.