Inhibition of Aurora-A results in increased cell death in 3-dimensional culture microenvironment, reduced migration and is associated with enhanced radiosensitivity in human nasopharyngeal carcinoma

Abstract

Mitosis related Aurora-A kinase is amplified in a variety of carcinomas. Overexpression of Aurora-A contributes to tumorigenesis and disease progression, and has emerged as an attractive molecular target for the design of anticancer drugs. In this study, we investigated the function of Aurora-A selectively small molecule inhibitor VX-680 in nasopharyngeal carcinoma (NPC) CNE-2 cells. We found that VX-680 suppressed proliferation and induced apoptosis of 2-dimensional (2-D) cultured NPC CNE-2 cells. Moreover, CNE-2 cells formed a tumor-like cell mass in 3-dimensional (3-D) matrix culture microenvironment, and the tumor mass formation could be impaired when pretreated with VX-680 for indicated time. Similarly, when adding VX-680 to preformed 3-D CNE-2 tumor mass, the tight spatial tumor mass experienced apparent apoptotic cell death and consequently dissociated into individual dead cells, as detected by cleaved Caspase-3 immunofluorescence assay. The migration assay showed that VX-680 decreased NPC CNE-2 cell migration ability in a dose-dependent manner. Our further study revealed that X-ray irradiation and VX-680 upregulated p53 expression level as well as arrested cell cycle in G2/M, sensitized NPC CNE-2 cells to radiation and effectively resulted in cell death. In summary, our data indicated that Aurora-A small molecule inhibitor VX-680, potently destructed tumor formation and induced apoptosis, reduced cell migration and enhanced radiosensitivity, offering a promising therapeutic agent for human NPC.