Metastasis is a major cause of cancer-related death in Triple-Negative Breast Cancer (TNBC). In TNBC, there is a significant correlation between metastasis and chemoresistance. Cancer relapse and metastasis are associated with the part of cancer cells with stem cell properties. These cancer stem cells are resistant to current cancer treatments. Due to their resistant nature, a significant relationship exists between the amount of cancer stem cells and chemoresistance. To our knowledge, to date, no comparative study was conducted on the number of these cells in metastatic loci vs. primary tumor site.
METHODS
In the present study, after developing a metastatic animal model of TNBC, metastatic and primary tumor
cells were extracted from the lung and primary tumor of cancerous mice, respectively. In the next
step, the sphere formation ability as a reliable in vitro assay to assess the presence and self-renewal ability
of CSCs, in metastatic and primary tumor cells was evaluated separately.
RESULTS
The results showed that sphere formation ability, and consequently the population of cancer stem cells
among metastatic tumor cells was significantly higher.
CONCLUSION
A higher percent of CSCs in lung metastatic site, compared with the primary tumor site, can partly explain
the reasons for the chemoresistance and relapse in metastatic TNBC.