*4.12. HUVEC Migration Assays*

Confluent HUVECs were grown in 24-well plates. To rule out the confounding influence of cell proliferation, the HUVECs were treated with 10 μg/mL mitomycin C (Sigma-Aldrich) for 2 h prior to the migration assay. A small linear scratch was created in the confluent monolayer by gently scraping with a sterile cell scrapper. The cells were extensively rinsed with M199 medium to remove cellular debris and then incubated with CM. Six hours later, images of the migrated cells were digitally photographed. The degree of wound closure was determined while using ImageJ ® program to measure the percent closure of the wounded area within the captured images.

## *4.13. HUVEC Tube Formation Assays*

HUVECs (2 × 10<sup>4</sup> cells/well in 96-well plates) were plated onto a thin coating of Matrigel (0.24 mg/cm2) with CM. After 6 h, each well was digitally photographed through phase contrast microscopy. Tubes are defined that develop contain a lumen encircled by endothelial cells that are joined together via junctional complexes and the number of intact tubes was counted per high power field.
