Chapter 5 - Vasculogenic mimicry

Abstract

Vasculogenic mimicry (VM) is a microvascular channel formed by invasive, metastatic, and hereditary dysregulated tumor cells. This process differs from angiogenesis, it occurs de novo in the absence of endothelial cells (tumor cells effectively mimic the true vascular endothelium). In 1999 it was first described by Maniotis et al. in uveal melanoma. Since then, VM has been found in several kinds of malignant tumor such as renal cell carcinoma, breast cancer, ovarian cancer, primary gallbladder cancer, malignant esophageal squamous cell carcinoma, mesothelioma, alveolar rhabdomyosarcoma, and hepatocellular carcinoma. PAS stain is routinely used in the display of VM. VM is a mechanism intrinsic to a number of human cancers that is associated with aggressive behavior. So it is a good indicator for patients’ outcome. Various chemical molecules pathways (Hypoxia/hypoxia-inducible factor pathway, vascular endothelial growth factor pathway, and Nodal pathway) that promote the VM formation in various cancers have been reported, but the confirmed mechanisms are still unknown. This review will focus on the character, stain, progress and prognosis significance, molecular pathways, and therapeutic strategy and of VM.