OBJECTIVE: To investigate the relationship between the promoter methylation and protein expression of insulin-like growth factor binding protein-related protein 1(IGFBP-rP1) in laryngeal squamous cell carcinoma (LSCC). METHOD: Methylation specific PCR (MSP) approach and immunohistochemistry methods were used to examine the methylation status and protein expression of IGFBP-rP1 in 45 samples of laryngeal carcinoma and 18 samples of tissues beside cancer. RESULT: For the promoter site, methylation frequency of IGFBP-rP1 in tumor specimens (33.3%, 15/45) was significantly higher than that in corresponding normal tissues (5.6%, 1/18) (P < 0.05). The protein expression of IGFBP-rP1 in tumor tissues was significantly higher than that in corresponding normal tissues (P < 0.05) and was inversely correlated with its methylation status of promoter. CONCLUSION: Epigenetic silencing of IGFBP-rP1 gene expression by promoter hypermethylation may play an important role in LSCC.
OBJECTIVE: To investigate the relationship between the promoter methylation and protein expression of insulin-like growth factor binding protein-related protein 1(IGFBP-rP1) in laryngeal squamous cell carcinoma (LSCC). METHOD: Methylation specific PCR (MSP) approach and immunohistochemistry methods were used to examine the methylation status and protein expression of IGFBP-rP1 in 45 samples of laryngeal carcinoma and 18 samples of tissues beside cancer. RESULT: For the promoter site, methylation frequency of IGFBP-rP1 in tumor specimens (33.3%, 15/45) was significantly higher than that in corresponding normal tissues (5.6%, 1/18) (P < 0.05). The protein expression of IGFBP-rP1 in tumor tissues was significantly higher than that in corresponding normal tissues (P < 0.05) and was inversely correlated with its methylation status of promoter. CONCLUSION: Epigenetic silencing of IGFBP-rP1 gene expression by promoter hypermethylation may play an important role in LSCC.