The purpose of the present study was to investigate the association between the expression of pituitary tumor-transforming 1 (PTTG1) and the expression of matrix metalloproteinase (MMP)-2 and MMP-9 in laryngeal carcinoma tissues, and to elucidate the association between PTTG1 expression and the prognosis of patients with laryngeal cancer. Immunohistochemical staining was used to detect PTTG1 expression in laryngeal cancer and normal tumor-adjacent laryngeal tissues. Western blotting was used to determine the levels of PTTG1 and MMP-2 and -9 in laryngeal carcinoma tissues and to assess their correlation. In addition, the associations between PTTG1 expression and the clinical parameters of laryngeal cancer and patient survival were determined. The immunohistochemistry results revealed that the positive expression rates of PTTG1, MMP-2 and MMP-9 in the laryngeal cancer tissues were significantly higher than those in the carcinoma-adjacent normal laryngeal tissues (all P<0.05). In addition, expression levels of PTTG1, MMP-2 and MMP-9 were significantly associated with lymph node metastasis, histological grade and clinical stage (P<0.05). Furthermore, the levels of PTTG1 were positively correlated with the levels of MMP-2 and MMP-9 in laryngeal cancer tissues (P<0.05). In summary, the expression levels of PTTG1, MMP-2 and MMP-9 are closely associated with the biological behaviors of laryngeal cancer tissues, showing that they serve important roles in the occurrence and development of laryngeal cancer, and may be useful as biological indicators of laryngeal tissue invasion, metastasis and patient prognosis.
Keywords: invasion; laryngeal cancer; matrix metalloproteinase 2; matrix metalloproteinase 9; metastasis; pituitary tumor-transforming 1; prognosis.