MCP‐1 expression in breast cancer and its association with distant relapse

Abstract

AbstractBackgroundDistant relapse of breast cancer complicates management of the disease and accounts for 90% of breast cancer‐related deaths. Monocyte chemoattractant protein‐1 (MCP‐1) has critical roles in breast cancer progression and is widely accepted as a pro‐metastatic chemokine.MethodsThis study explored MCP‐1 expression in the primary tumour of 251 breast cancer patients. A simplified ‘histoscore’ was used to determine if each tumour had high or low expression of MCP‐1. Patient breast cancers were retrospectively staged based on available patient data. p < 0.05 was used to determine significance and changes in hazard ratios between models were considered.ResultsLow MCP‐1 expression in the primary tumour was associated with breast cancer‐related death with distant relapse in ER− breast cancers (p < 0.01); however, this was likely a result of most low MCP‐1‐expressing ER− breast cancers being Stage III or Stage IV, with high MCP‐1 expression in the primary tumour significantly correlated with Stage I breast cancers (p < 0.05). Expression of MCP‐1 in the primary ER− tumours varied across Stage I, II, III and IV and we highlighted a switch in MCP‐1 expression from high in Stage I ER− cancers to low in Stage IV ER− cancers.ConclusionThis study has emphasised a critical need for further investigation into MCP‐1's role in breast cancer progression and improved characterisation of MCP‐1 in breast cancers, particularly in light of the development of anti‐MCP‐1, anti‐metastatic therapies.