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Updated: Jun 23, 2026

Detection of a Circulating MicroRNA Custom Panel in Patients with Metastatic Colorectal Cancer
Published on: March 14, 2019
Biomarkers correlate with colon cancer and risks: a preliminary study
Shan Lu1, Yanek S Y Chiu, Andrew P Smith
1California Pacific Medical Center Research Institute, San Francisco, California 94107, USA.
Purpose:
We previously reported that gene expression analysis of biopsies of normal-appearing large intestinal mucosa can distinguish individuals with colonic cancer and many individuals at risk for colon cancer from controls. The purpose of this study was to determine whether noninvasively removed rectal swabs can identify individuals with colon cancer or risk of colon cancer as effectively as we previously demonstrated using biopsies.
Methods:
Rectal mucosa cells were removed by rectal swabs, and their gene expression profiles were compared with those of biopsies removed by colonoscopy. Expression of 16 genes in the rectal mucosa of 12 individuals with colon cancer, 25 with polyps, 37 with family or self-reported cancer history, and 23 controls was measured by real-time reverse transcription-polymerase chain reaction.
Results:
We found similar results using rectal swabs and biopsies. Groups of individuals with or at risk for cancer showed an altered gene expression profile compared with controls. Moreover, each of the 12 cancer patients showed altered expression relative to the mean of controls.
Conclusions:
Gene expression analysis using rectal swabs may provide a convenient way to screen for colon cancer.