Expression and Clinical Significance of The N-myc downstream regulated gene-1 in Hypopharyngeal Cancer
Objective. N-myc downstream regulated gene-1 (Ndrg-1), a potent metastasis suppressor gene, is identified as a gene that is up-regulated by the induction of differentiation in various cancer cell lines. Ndrg-1 has been shown to be involved in tumor progression and metastasis in colon, prostate and breast cancer. However, the clinical significance of Ndrg-1 in hypopharyngeal cancer remains to be investigated, and we therefore examined the role of Ndrg-1 in the survival rate, invasion and metastasis of hypopharyngeal squamous cell carcinoma (SCC). Materials and methods. We performed immunohistochemical staining of 56 specimens each of normal mucosa and SCC of the hypopharynx with Ndrg-1 antibodies. For reverse transcriptase polymerase chain reaction (RT-PCR) and Western blotting, fresh normal and cancer tissue from the hypopharynx obtained from three patients were used. Results. Positive rates of Ndrg-1 expression in hypopharyngeal SCC were 21.4%, respectively. Ndrg-1 staining was significantly inverse correlated with lymph node metastasis. (p=0.048) Decreased expression of Ndrg-1 protein (Western blotting) was detected in hypopharyngeal cancer tissue. Conclusion. Our results suggest that N-myc downstream regulated gene-1 (Ndrg-1) may play an important role in the progression and metastasis of hypopharyngeal cancer.
