Expression levels of SIX1, ME2, and AP2M1 in adenoid cystic carcinoma and mucoepidermoid carcinoma.

Abstract

Adenoid cystic carcinoma (AdCC) and mucoepidermoid carcinoma (MEC) are the most frequent malignancies in the salivary glands. The purpose of this study was to explore the roles of sine oculis homeobox homolog 1 (SIX1), malic enzyme 2 (ME2), and AP-2 complex subunit mu (AP2M1) in AdCC and MEC, as well as the potential relationship between SIX1, ME2, AP2M1, and proliferation marker cyclin D1. Immunohistochemistry was performed on human salivary gland tissue microarrays that contained 76 normal salivary glands (NSGs), 14 pleomorphic adenomas (PMAs), 81 AdCCs, and 52 MECs. We observed that the expression levels of SIX1 and ME2 were significantly elevated in AdCC and MEC when compared with NSG and PMA. In addition, we detected that AP2M1 was overexpressed in AdCC and MEC when compared with NSG. We also found that SIX1 and AP2M1 were positively associated with cyclin D1. These results may prove that SIX1 and AP2M1 are involved in the proliferation of AdCC and MEC to cause tumor growth.