[Three-dimensional cell culture and histology of vasculogenic mimicry in hepatocellular carcinoma].

Background & Objective: Vasculogenic mimicry (VM) is a blood supply pattern in malignant tumors. Mimic vessel walls are formed by tumor cells, not by endothelial cells. Previous studies of VM are limited on malignant tumors with high aggression and bi-directional differentiation potentials, but seldom on epithelium-originated tumors. This study was to observe VM in hepatocellular carcinoma (HCC) by 3-dimensional culture of HCC cell line HepG2 and immunohistochemistry.
Methods: Three-dimensional culture system of HepG2 cells was constructed to observe VM. The presence of VM in 15 specimens of HCC was observed by immunohistochemical and histological double staining of CD31 and PAS, or Ferritin and PAS.
Results: During 3-dimensional culture, HepG2 cells stretched out thin and long apophyses at the second day, and linked each other to form wreath and net-work structure at the seventh day. All of the 15 HCC simples showed CD31-positive for endothelial cells, and Ferritin-positive for tumor cells. The immunohistochemical and histological double staining also proved that VM, formed by CD31-negative and Ferritin-positive tumor cells, existed in 7 of the 15 simples of HCC. Tumor cells were separated from the tubes by PAS-positive matter like basement membrane. Red blood cells could be seen in the tubes. The number of VM was less in well differentiated simples than in poorly differentiated samples; CD31-positive tumor cells were observed in poorly differentiated samples.
Conclusions: HepG2 cells have the capacity of self-metamorphosing and vasculorizing. Tumor cells can obtain oxygen and nutrition through VM.