MicroRNA Signatures: Novel Biomarker for Colorectal Cancer?

Abstract

Aberrant microRNA (miRNA) expression might be of potential use as diagnostic and prognostic biomarker for cancers. We reviewed studies published until March 2011 which assessed expression of miRNAs in colorectal cancer (CRC)/adenoma tissue and normal colorectal mucosa and in plasma of CRC/adenoma patients and healthy controls. Overall, 20 studies that investigated miRNA expression in tissue and 3 studies that investigated miRNA levels in plasma were included. A total of 160 miRNAs were found to be dysregulated in CRC. MiR-20a and miR-31 were found to be significantly upregulated in more than one study, and miR-143 and miR-145 were found to be significantly downregulated in CRC tissue in six or more studies. MiR-92a was significantly upregulated in CRC patients in two of the plasma-based studies and in CRC tissue in one of the tissue-based studies. Our results provide timely and relevant information for miRNAs as potential diagnostic biomarkers for CRC. The expression of miRNAs in plasma may be indicative of presence of CRC. Larger diagnostic studies are needed to evaluate potential use of miRNA expression in early detection and diagnosis of CRC. Cancer Epidemiol Biomarkers Prev; 20(7); 1272-86. Ó2011 AACR.

Identification of microRNA-135b in Stool as a Potential Noninvasive Biomarker for Colorectal Cancer and Adenoma

“…This provides a rationale of utilizing stool miRNA for the detection of CRC and adenomas. So far, four other studies have reported the use of stool-based miRNA as a screening tool for CRC (19)(20)(21)(22). Most of these studies involved small cohorts and were limited to the investigation of CRC.…”

Serum expression levels of miR-17, miR-21, and miR-92 as potential biomarkers for recurrence after adjuvant chemotherapy in colon cancer patients

“…Only a few studies have evaluated the expression levels of miRNAs after curative surgical resection of the primary tumor (21,27,28) and have looked for a diagnostic correlation between serum levels of miRNAs and post-adjuvant levels of CEA. In the present study the expression levels and the diagnostic significance of 4 circulating miRNAs (miR-17, miR-21, miR-29a and miR-92) from blood samples of colon cancer patients, who underwent radical surgery of the primary tumor and adjuvant chemotherapy were correlated with the serum levels of CEA (measured after end of adjuvant chemotherapy) and the stage of the disease.…”

MicroRNAs as molecular markers for colon cancer Diagnostic screening in stool & blood

“…It should be emphasized that although not all of the shed cells in stool are derived from a tumor, data published by us and others [25,27,28,[56][57][58][59][60][61][62][63][64][65][66][67][68] have indicate that diagnostic miRNA gene expression profiles are associated with adequate number of exfoliated cancerous cells and enough transformed RNA is released in the stool, and also the availability of measurable amount of circulating. miRNA genes in blood (either cellular or extracellularly), which can be determined quantitatively by a sensitive technique such as PCR in spite of the presence of bacterial DNA, non-transformed RNA and other interfering substances.…”

“…In comparison to the commonly employed FOBT stool test, a noninvasive molecular and reliable test would particularly be more convenient as there would be no requirement for dietary restriction, or meticulous collection of samples, and thus a screening test would be acceptable to a broader segment of the population. Using stable molecules such as miRNAs that are not easily degradable when extracted from stool or blood and manipulated thereafter, a miRNA -approach for colon cancer is thus preferable to a transcriptomic mRNA-, mutation DNA-, epigeneticor a proteomic-based test [25,27,[55][56][57][58][59][60][61][62][63][64][65][66][67][68], particularly that we and others have shown that these stable, nondegradable miRNA molecules can be easily extracted from stool or from circulation in vitro using commercially available kits. Advantages and disadvantages of the in vivo and in vitro tests are presented in table 1.…”

“…Several of the miRNAs were shown by microarrays, NGS and RTqPCR in CRC tissue, cell culture lines, stool and blood to be related to colon cancer tumorigenesis [25,27,28,[54][55][56][57][58][59][60][64][65][66][67][68]86,87,94,98,114,123] and UC [25,95]. A study indicated that a combination of mRNA and miRNA expression signatures represent a broader approach for improving biomolecular classification of CRC [123].…”