Published online May 7, 2019. doi: 10.3748/wjg.v25.i17.2099
Peer-review started: February 15, 2019
First decision: March 5, 2019
Revised: March 25, 2019
Accepted: April 10, 2019
Article in press: April 10, 2019
Published online: May 7, 2019
Processing time: 81 Days and 15.7 Hours
The methylated septin 9 (mSEPT9) assay was the first blood-based test approved by the United States Food and Drug Administration as a colorectal screening test. Previous researchers found that mSEPT9 was a powerful screening, diagnostic, monitoring, and prognostic tool for German colorectal cancer (CRC) patients. However, the diagnostic and prognostic value of mSEPT9 in Chinese CRC patients is still unknown, and may be affected by differences in ethnicity and socioeconomic status.
To explore the diagnostic and prognostic value of serum mSEPT9 for Chinese CRC patients.
This study aimed to explore the diagnostic value of preoperative serum mSEPT9 in the Chinese population, and then assess the value of quantitative mSEPT9 levels for CRC staging. In addition, Chinese population and TCGA database information were combined to determine the prognostic significance of mSEPT9 by bioinformatics analyses.
Three hundred fifty-four subjects (300 CRC, 54 normal) from China and 351 subjects (330 CRC, 21 normal) from the TCGA database including American Indian, Asian, Black, and African American populations were retrospectively analyzed. Preoperative mSEPT9 levels were quantified by quantitative methylation-specific polymerase chain reaction. Kaplan-Meier univariate assay was performed to analyze potential prognostic factors including overall survival (OS) and progression-free survival (PFS).
In Chinese CRC patients, positive mSEPT9 and quantitative mSEPT9 levels were strongly associated with clinico-pathological parameters. The patients with positive mSEPT9 showed a tendency toward lower PFS. Higher mSEPT9 levels were correlated with more distant metastasis among the TCGA database patients, and patients with high mSEPT9 levels showed a tendency toward lower OS.
Testing for mSEPT9 is a powerful diagnostic and promising prognostic tool for Chinese CRC patients; it may add valuable information to current tumor staging and holds the potential to monitor CRC recurrence.
This study assessed the correlation between clinicopathological characteristics and preoperative serum mSEPT9 in Chinese CRC patients and, further, to confirm the correlation between mSEPT9 levels and CRC prognosis by bioinformatics analyses. In addition, we analyzed methylated sites that were co-upregulated or co-downregulated in colon and rectum tumors, to provide the theoretical guidance for further research.