Infantile hemangioma (IH) is the most prevalent type of vascular tumor in infants. The pathophysiology of IH is unknown. The tissue structure and physiology of two-dimensional cell cultures differ greatly from those in vivo, and spontaneous regression often occurs during tumor formation in nude mice and has severely limited research into the pathogenesis and development of IH. By decellularizing porcine aorta, we attempted to obtain vascular-specific extracellular matrix as the bioink for fabricating micropattern arrays of varying diameters via microcontact printing. We then constructed IH-derived CD31+ hemangioma endothelial cell three-dimensional microtumor models. The vascular-specific and decellularized extracellular matrix was suitable for the growth of infantile hemangioma-derived endothelial cells. The KEGG signaling pathway analysis revealed enrichment primarily in stem cell pluripotency, RAS, and PI3KAkt compared to the two-dimensional cell model according to RNA sequencing. Propranolol, the first-line medication for IH, was also used to test the model's applicability. We also found that metformin had some impact on the condition. The three-dimensional microtumor models of CD31+ hemangioma endothelial cells were more robust and efficient experimental models for IH mechanistic exploration and drug screening.

Hepatic hemangioma (HH) is the most common benign liver tumor and it is usually found incidentally during radiological studies. This tumor arises from a vascular malformation; however, the pathophysiology has not been clearly elucidated. Symptoms usually correlate with the size and location of the tumor. Less commonly the presence of a large HH may cause life-threatening conditions. The diagnosis can be established by the identification of HH hallmarks in several imaging studies. In patients that present with abdominal symptoms other etiologies should be excluded first before attributing HH as the cause. In asymptomatic patient's treatment is not required and follow up is usually reserved for HH of more than 5 cm. Symptomatic patients can be managed surgically or with other non-surgical modalities such as transcatheter arterial embolization or radiofrequency ablation. Enucleation surgery has shown to have fewer complications as compared to hepatectomy or other surgical techniques. Progression of the tumor is seen in less than 40%. Hormone stimulation may play a role in HH growth; however, there are no contraindications for hormonal therapy in patients with HH due to the lack of concrete evidence. When clinicians encounter this condition, they should discern between observation and surgical or non-surgical management based on the clinical presentation.