This pilot study is the first to focus on the potential role of death-associated protein 1 (DAP1) in human breast cancer.
Materials and methods: A total of 153 samples were studied. DAP1 transcription levels were determined using quantitative polymerase chain reaction (qPCR). Transcript levels within breast cancer specimens were compared to those of normal background tissues and correlated with clinicopathological data accumulated over a 10-year follow-up period.
Results: The expression of DAP1 mRNA was demonstrated to decrease with increasing Nottingham Prognostic Index (NPI2 vs. NPI3, p=0.0026), and TNM stage (TNM1 vs. 4, p=0.0039). Lower DAP1 expression levels were significantly associated with local recurrence (p=0.02) and distant metastasis (p=0.001).
Conclusion: This study demonstrates an inverse association between DAP1 mRNA levels and tumour stage and clinical outcome in breast cancer; thus, providing evidence that DAP1 plays a pro-apoptotic role in human breast cancer. The relationship between oncogenesis and the autophagy pathway merits further investigation.