Key Points
• Source: Journal of Personalized Medicine
• Conclusion/Relevance: “This is the first study to evaluate both CBR1 [cannabinoid receptor 1] and CBR2 [cannabinoid receptor 2] expression in association with breast cancer prognostic factors and survival. We evaluated CBR expression in breast cancer tissue. CBR1 cytoplasmic expression seemed to be associated with poor prognostic factors, while CBR2 nuclear expression seemed to be associated with better prognostic factors. The cytoplasmic expression of CBR2 may be involved in the occurrence of locoregional and distant recurrences. Although the few events occurring during the follow-up may have limited the detection of significant associations, these results indicate that CBR expression in breast cancer needs further investigation.”
• In the current study, researchers assessed CBR1 and CBR2 expression in breast neoplasms and its prediction of prognostic factors and survival. Expression was determined via immunohistochemistry. CBR1 expression was positively correlated with lymph node metastases and HER2 status. On the other hand, nuclear CBR2 expression was positively correlated with histologic type, ER/PR positive status, and negatively correlated with tumor grade. Moreover, cytoplasmic CBR2 expression was positively associated with higher locoregional and distant recurrences, although this finding was not significant.
• Strengths of the current study include a large sample size (n=522) with consecutive inclusion of eligible patients representative of all breast cancer subtypes. The major limitation of the current study was the low number of events that occurred during follow-up despite the large sample size and long duration of the study.
• Discussion questions: What are your thoughts about the clinical relevance of cannabinoid receptors? What potential do you think cannabinoid receptors present in oncology?