BACKGROUND Recently, it was demonstrated that sup-pressor of cytokine signaling-1 (SOCS-1) was frequently silenced by methylation of its CpG island inhuman 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 a nearly onset of colorectal cancer.