Serum Biomarker Detects Colorectal Cancer Early

A noninvasive molecular test has been developed that measures methylation of a gene in tissues and blood sera as a biomarker for the early detection of cancer.

The gene was identified as the syndecan-2 (SDC2) gene, which encodes for the membrane syndecan-2 protein that is known to participate in cell proliferation, cell migration, and is expressed in colon mesenchymal cells.

Scientists at the Yonsei University College of Medicine (Seoul, Republic of Korea) working with colleagues at Genomictree, Inc. (Daejeon, Republic of Korea) performed DNA microarray analysis coupled with enriched methylated DNA using tissues from primary tumors and nontumor tissues from 12 Colorectal Cancer (CRC) patients. After stepwise filtering, they found a set of genes that were highly methylated across all of the CRC tumors, and of particular importance was SDC2. The methylation level of target region of SDC2 assessed in tumor tissue was found to be significantly higher than that from paired adjacent nontumor tissue.

The biomarker was validated by analyzing SDC2 methylation levels in primary tumors and paired-adjacent nontumor tissue samples from 133 CRC patients. The investigators found that in the transcriptional regulatory region of the SDC2 gene, tumor samples showed significantly higher levels of methylation than the control samples. The SDC2 methylation positivity ranged from 92.9% to 100% when samples were stratified according to stages of cancer. The SDC2 biomarker could also be measured in serum samples from CRC patients and healthy individuals.

Fluorescence-based quantitative methylation-specific polymerase chain reaction (qMSP) was used to determine SDC2 methylation in the serum DNA.

TaeJeong Oh, PhD, the lead author of the study said, “The SDC2 methylation test was able to detect 92% for detection of stage I cancer patients indicating that SDC2 is suitable for early detection of CRC where therapeutic interventions have the greatest likelihood of curing the patient from the disease.” Sungwhan An, PhD, CEO of Genomictree and senior author of the study, said, “We are very excited with this result using a small amount of serum DNA from less than 1 mL of blood. I believe a greater volume of blood will further improve the clinical performance of this test. We are currently preparing another set of clinical validation studies evaluating SDC2 methylation in serum DNA from patients with early adenoma.” The study was published on June 7, 2013, in the Journal of Molecular Diagnostics.

Related Links:
Yonsei University College of Medicine
Genomictree, Inc.