Development and characterization of a high-throughput in vitro cord formation model insensitive to VEGF inhibition

Falcon BL, O'Clair B, McClure D, Evans GF, Stewart J, Swearingen ML, Chen Y, Allard K, Lee LN, Neote K, McEwen DP, Uhlik MT, Chintharlapalli S
Source: J Hematol Oncol
Publication Date: (2013)
Issue: 6: 31
Research Area:
Basic Research
Cells used in publication:
Endothelial, umbilical vein, human (HUVEC)
Species: human
Tissue Origin: vein
Fibroblast, dermal (NHDF-Neo), human neonatal
Species: human
Tissue Origin: dermal
Fibroblast, dermal(NHDF-Ad), human adult
Species: human
Tissue Origin: dermal
Adipose stem cell, human normal
Species: human
Tissue Origin: adipose
Endothelial, colony forming, human(ECFC)
Species: human
Tissue Origin: extra-embryonic


BACKGROUND: Anti-VEGF therapy reduces tumor blood vessels, however, some vessels always remain. These VEGF insensitive vessels may help support continued tumor growth and metastases. Many in vitro assays examining multiple steps of the angiogenic process have been described, but the majority of these assays are sensitive to VEGF inhibition. There has been little focus on the development of high-throughput, in vitro assays to model the vessels that are insensitive to VEGF inhibition. METHODS: Here, we describe a fixed end-point and kinetic, high-throughput stem cell co-culture model of cord formation. RESULTS: In this system, cords develop within 24 hours, at which point they begin to lose sensitivity to VEGF inhibitors, bevacizumab, and ramucirumab. Consistent with the hypothesis that other angiogenic factors maintain VEGF-independent vessels, pharmacologic intervention with a broad spectrum anti-angiogenic antagonist (suramin), a vascular disrupting agent (combretastatin), or a combination of VEGF and Notch pathway inhibitors reduced the established networks. In addition, we used our in vitro approach to develop an in vivo co-implant vasculogenesis model that connects with the endogenous vasculature to form functional blood vessels. Similar to the in vitro system, over time these vessels become insensitive to VEGF inhibition. CONCLUSION: Together, these models may be used to identify novel drugs targeting tumor vessels that are not sensitive to VEGF inhibition.