Tumor-associated macrophages increase COX-2 expression promoting endocrine resistance in breast cancer via the PI3K/Akt/mTOR pathway

This article is dedicated to discuss the role of TAMs in the endocrine resistance of breast cancer. It was found that tamoxifen-resistant MCF-7 cells induced more macrophages polarized into TAMs. Conversely, TAMs increased the expression of cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2), which promoted tamoxifen resistance through the activation of the PI3K/Akt/mTOR signaling pathway in MCF-7 cells. Furthermore, clinical analysis supported that five-year progression-free survival (PFS) of breast cancer patients with abundant COX-2 expression in TAMs was shorter (p<0.05). Therefore, these results show a positive feedback loop between TAMs and breast cancer cells, suggesting that TAMs and COX-2 may be new therapeutic targets for breast cancer patients suffering from endocrine resistance.PMID:34619972 | DOI:10.4149/neo_2021_201226N1404
Source: Neoplasma - Category: Cancer & Oncology Authors: Source Type: research