Proliferating Infantile Hemangioma Tissues and Primary Cell Lines Express Markers Associated with Endothelial-to-Mesenchymal Transition.

Background: We have previously shown that the endothelium of the microvessels of infantile hemangioma (IH) exhibits a hemogenic endothelium phenotype and proposed its potential to give rise to mesenchymal stem cells, similar to the development of hematopoietic cells. This endothelial-to-mesenchymal transition (Endo-MT) process involves the acquisition of a migratory phenotype by the endothelial cells, similar to epithelial-to-mesenchymal transition that occurs during neural crest development. We hypothesized that proliferating IH expresses Endo-MT-associated proteins and investigated their expression at the mRNA, protein, and functional levels.

A placental chorionic villous mesenchymal core cellular origin for infantile haemangioma.

Aims: To investigate the expression of the placental cell-specific associated proteins in infantile haemangioma (IH).

Methods: Immunohistochemical staining was used to investigate the expression of human chorionic gonadotrophin (hCG), human placental lactogen (hPL), human leucocyte antigen-G (HLA-G), cytokeratin 7 (CK7) and smooth muscle actin in paraffin-embedded sections of proliferating and involuted IHs.

Results: The proteins hCG and hPL were expressed by the endothelium but not the pericyte layer of proliferating IH, but these proteins were not detected in involuted lesions.