1693
To this end , two candidate anti - angiogenic RNA - damaging agents , onconase and ( - 4 ) rhEDN , were screened for their effects on endothelial cell proliferation using three distinct types of endothelial cells in culture : HPV - 16 E6 / E7 - immortalized human umbilical vein endothelial cells ( HUVECs ) , a Kras - transformed HPV - 16 E6 / E7 HUVEC ( Rhim et al . , Carcinogenesis 4 , 673 - 681 , 1998 ) , and primary HUVECs .
 endothelial cell, endothelial cells, human umbilical vein endothelial cells, HUVECs, HUVEC, HUVECs
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Anatomy 
Text: {0} 
Answer:
 endothelial cell, endothelial cells, human umbilical vein endothelial cells, HUVECs, HUVEC, HUVECs