A Four-Gene Panel in Rectal Swab Samples as a Biomarker for Colorectal Cancer Screening.

Area of Science:

• Oncology
• Molecular Biology
• Biomarker Discovery

Background:

• Gene expression dysregulation is a hallmark of colorectal cancer (CRC) development.
• Investigating rectal swab specimens for gene expression changes offers a potential non-invasive screening method for CRC.

Purpose of the Study:

• To determine if gene expression dysregulation in colorectal tissue is detectable in rectal swabs.
• To evaluate the potential of rectal swab gene expression as a non-invasive biomarker for CRC screening.

Main Methods:

• Compared expression of 14 CRC-associated genes in tumor and adjacent non-tumor tissues.
• Correlated gene expression levels between colorectal tissue and paired rectal swab specimens.
• Evaluated diagnostic potential of individual genes and a four-gene panel in rectal swabs from CRC patients, polyp patients, and controls.

Main Results:

• Significant upregulation of 11 genes (CXCR2, SAA, COX1, PPARδ, PPARγ, Groγ, IL8, p21, c-myc, CD44, CSF1) observed in CRC tissue.
• High correlation of gene expression levels between CRC tissue and rectal swabs for most genes.
• A four-gene panel (CD44, IL8, CXCR2, c-myc) identified CRC patients with AUC 0.83, precancerous adenoma with AUC 0.7322, and overall polyps with AUC 0.6522.

Conclusions:

• Gene expression in rectal swabs accurately reflects colorectal tissue dysregulation.
• The identified four-gene panel serves as a promising non-invasive biomarker for early detection of precancerous adenomas and CRC.