Tumor-Associated Macrophage Promotes the Survival of Cancer Cells upon Docetaxel Chemotherapy via the CSF1/CSF1R-CXCL12/CXCR4 Axis in Castration-Resistant Prostate Cancer

Castration-resistant prostate cancer (CRPC) is an advanced stage of prostate cancer that can progress rapidly even in patients treated with castration. Previously, we found that tumor-associated macrophages (TAM) can be recruited by CSF-1 secreted by docetaxel-treated prostate cancer cells and promote the survival of cancer cells in response to chemotherapy. The inhibition of CSF-1R can impede this effect and significantly prolong survival in xenograft mice. However, the actual mechanism of how TAM improves cancer cell survival still remains elusive and controversial. Here, for the first time, we found that the enhanced survival of cancer cells achieved by TAM was mainly mediated by CXCR4 activation from the increased secretion of CXCL12 from CSF-1 activated TAM. This finding helps to clarify the mechanism of chemoresistance for second-line chemotherapy using docetaxel, facilitating the development of novel drugs to overcome immune tolerance in castration-resistant prostate cancer.

Automated summary

The study found that TAM activates CXCR4 by increasing secreted CXCL12, enhancing the survival of cancer cells and elucidating the mechanism of TAM in chemotherapy. This finding may aid in the development of new drugs to overcome immune tolerance in castration-resistant prostate cancer.