Functional analysis of OCIAD2 in hepatoblastoma
Hepatoblastoma (HB) is the most common malignant liver tumor in children; however, the molecular mechanisms responsible for its progression remain unclear. We previously identified hypermethylation of the ovarian cancer immunoreactive antigen domain containing 2 (OCIAD2) as a poor prognostic factor for HB in a genome-wide methylation analysis of HB excision specimens. As it has been already reported that such hypermethylation of OCIAD2 dysregulates the expression of OCIAD2, to elucidate the function of OCIAD2 in HB, we evaluated altered cellular functions such as cell growth, invasion, and migration abilities using OCIAD2 overexpression cell lines of HB. In the in vitro analysis with OCIAD2 overexpression, no significant difference was observed in cell proliferation between the groups. However, migration and invasion abilities were significantly lower in OCIAD2 overexpressed cell lines. Second, overexpression of OCIAD2 reduced matrix metalloproteinase 2 (MMP2) levels in each cell line. These results suggest that OCIAD2 suppresses HB invasion and migration in relation to MMP2.