Article Abstract

Exploring protocol for breast cancer xenograft model using endothelial colony-forming cells

Authors: Hyun Kyung Lim, Hyunsook Lee, Aree Moon, Kyu-Tae Kang, Joohee Jung


Background: Triple-negative breast cancer (TNBC) has poor prognosis because it tends to be metastatic and invasive. To improve TNBC therapeutic strategies, a xenograft model mimicking the early stage of metastasis is needed. Angiogenesis plays an important role in tumor progression, including tumor growth and metastasis. In Angiogenesis is a key requirement in TNBC xenograft models, thus, the cells forming blood vessels are needed. Circulating endothelial progenitors and endothelial colony-forming cells (ECFCs) have a high proliferative capacity and form new blood vessels by differentiating into the endothelium. In this study, a xenograft model was established for the evaluation of tumor progression based on the orthotopic implantation of MDA-MB-231 cells with the ECFCs.
Methods: The human breast cancer MDA-MB-231 cells with or without ECFCs were transplanted into fat pads of female Balb/c-nude mice using two protocols that differed only in terms of the number of MDA-MB-231 cells implanted. Then, two protocols were evaluated using tumorigenicity, tumor growth, and tumor weight as parameters of tumor progression. Furthermore, the existence of ECFCs and their role were studied in the tumor tissues.
Results: The results indicated that ECFCs increased the incidence and growth of MDA-MB-231 cell-derived tumors. The effects of ECFCs on tumor progression were particularly striking when 300,000 MDA-MB-231 cells were implanted using protocol two.
Conclusions: This protocol could be utilized for fundamental studies on TNBC tumor progression and provides a means for evaluating chemotherapeutic candidates for the treatment of TNBC.