The Cancer Testis Antigen PRAME: Expression in Triple Negative Breast Cancer

Background

Triple Negative Breast Cancer (TNBC) is a subtype of breast cancer that is clinically characterized by the absence of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). TNBC is a heterogeneous disease with distinct molecular profile, aggressive nature, poor prognosis and lack of targeted therapies. Recent studies demonstrate that TNBC may be a cancer testis antigen (CTA)- rich tumor, raising the possibility of CTA-based immunotherapy and cancer vaccines as a potential therapeutic approach for patients with TNBC. The focus of this study was to investigate the expression of preferentially expressed antigen of melanoma (PRAME), one member of the CTA family, in TNBC and non-TNBC cell lines in order to select appropriate cell lines to enable future research into functional role of PRAME in the progression of TNBC.

Methods

Five TNBC cell lines (MDA-MB-231, MDA-MB-468, MDA-MB-453, HCC70 and BT549) along with one non-TNBC cell line (MCF7) were used to investigate the expression of PRAME using qPCR, western blot and immunofluorescence techniques.

Results

PRAME expression was detected in 2 out of 5 TNBC cell lines (HCC70 and BT549), both represents different molecular TNBC subtypes. Higher expression of PRAME was detected in HCC70 compared to BT549.

Conclusion

At the end, our study showed that PRAME expression isn't specific to TNBC tumors overall or to TNBC molecular subtypes.