Aberrant methylation of SOCS-1 was observed in younger colorectal cancer patients

Background Recently, it was demonstrated that suppressor of cytokine signaling-1 (SOCS-1) was frequently silenced by methylation of its CpG island in human hepatocellular carcinoma (HCC). To define the role of SOCS-1 in the tumorigenic pathway of the colorectum, we examined the methylation of SOCS-1 in tumors of colorectal cancer patients. Methods. We examined 74 colorectal cancer patients, using a methylation-specific polymerase chain reaction (PCR; MSP) for SOCS-1 CpG island in primary tumors. Results. Aberrant methylation of the SOCS-1 CpG island was detected in 6 of the 74 (8%) colorectal cancer specimens. No corresponding normal colorectal tissues showed SOCS-1 methylation. We then analyzed the correlation between the clinicopathological features and SOCS-1 aberrant methylation and found that younger age was significantly related to SOCS-1 methylation (P = 0.048). Conclusions. These findings suggested that SOCS-1 may act as a tumor suppressor in at least some colorectal cancers and that SOCS-1 methylation may be a particular phenomenon related to an early onset of colorectal cancer.