RESUMO
Objective To observe vasculogenic mimicry (VM) of human choroidal melanoma cell line OCM-1 cultured in vitro and the expression of PI3K and EphA2 protein,as well as to explore the possible mechanisms.Methods OCM-1 cells were cultured in vitro and stained with periodic acid Schiff (PAS) on days 7,which aimed to observe the formation of PAS-positive cyclic structures,that is,VM formation.Then immunohistochemical staining was performed to detect PI3K and EphA2 on day 1,4,7 and the results were observed.Ressults On day 4 of 3-demintional culture,most of OCM-1 cells were polygonal and the cytoplasm was abundant;the nuclei were round and the nucleoli were visible.A small part of the tumor cells were long spindle.It was found that several long spindle cells were connected to each other to form hemicyclic structure.After 7 days,a large number of tumor cells became long spindle,growing along the collagen scaffold,and long protrusions appeared,forming a ring structure.PAS staining showed that the tumor cells were mostly arranged in a row,and tumor cells imitated the formation of body blood vessels,resulting in cell band and pipeline-like cell layers,with one layer of extracellular matrix (PAS-positive substance) making up the ring structure.Moreover,the expression levels of PI3K and EphA2 on day 4 and 7 were significantly higher than those on day 1 (all P ＜ 0.05),and their expression levels on day 7 were higher than those on day 4 (all P ＜ 0.05).Conclusion EphA2 and PI3K may play an important role in the VM formation in 3-dimentional culture of human choroidal melanoma cell line OCM-1.