Table 4.
Gene-specific methylation markers in rectal cancer patients receiving neoadjuvant chemoradiation.
| First Author and Year | Tumor | Overall Population (Treated Patients) | Treatment | Samples | Markers | Methods | Response to Treatment | Other Findings |
|---|---|---|---|---|---|---|---|---|
| De Maat, M.F., 2010 [75] | Rectal cancer | 251 (251) | Chemoradiation | Tumor tissues | MINT loci | Absolute quantitative assessmen tof methylated alleles |
Not examined | MINT3 hypermethylation and MINT17 hypomethylation reduced the risk of recurrence |
| Ebert, M.P., 2012 [76] | Rectal cancer | 220 (NA) | Chemoradiation | Tumor tissues | TFAP2E | MethyLight assay | TFAP2E hypermethylation was associated with non-response to neoadjuvant chemoradiation. The odds of adequate response were higher in patients with TFAP2E hypomethylation compared with the whole cohort | NA |
| Molinari, C., 2013 [77] | Rectal cancer | 74 (74) | Chemoradiation | Tumor tissues | 24 genes | Methylation-specific multiplex ligation-dependent probeamplification | In patients receiving neoadjuvant therapy, TIMP3 methylation status was significantly different across four tumor regression grade classes | Compared with adjacent normal tissues, tumor samples exhibited hypermethylation of ESR1, CDH13, RARB, IGSF4, and APC genes |
| Sun, W., 2013 [78] | Rectal cancer | 34 (34) | Chemoradiation | Serum | MGMT | MS-PCR | Serum MGMT hypermethylation was associated with improved response to treatment and higher regression compared with MGMT hypomethylation | NA |
Abbreviations: MINT, Methylated-IN-Tumour loci; TFAP2E, Transcription Factor Activating Protein 2 Epsilon; ESR1, Estrogen Receptor 1; CDH13, Cadherin 13; RARB, Retinoic Acid Receptor Beta; IGSF4, Cell Surface Adhesion Molecule; APC, Adenomatous Polyposis Coli; TIMP3, Tissue Inhibitor of Metalloproteinases 3; MS-PCR, methylation-specific PCR; MGMT, O6-methylguanine-DNA methyltransferase.