CTCs‐derived xenograft development in a triple negative breast cancer case.

Triple‐negative breast cancer (TNBC) is characterized by high rates of metastasis and no available molecular targets. CTCs derived xenografts (CDX) have demonstrated to be a promising tool for understanding cancer biology. In our study, a CDX from a TNBC patient was developed for the first time. After CDX characterization, WNT signaling was found as the main mechanism related with this tumor biology and potential CTCs markers were identified and subsequently validated in TNBC patients. In this cohort high levels of MELK expression were associated with poorer survival rates. Overall, our study demonstrates that CTCs from TNBC are tumorigenic and CDXs are a useful model to obtain valuable information about the tumor. What's new? Circulating tumor cells (CTCs) hold promise as a liquid biopsy and model to study tumor biology. However, technical limitations toward CTCs molecular characterisation and ex vivo expansion remain. This work describes for the first time the development of a CTCs‐derived xenograft (CDX) from a metastatic Triple Negative Breast Cancer (TNBC) patient, with WNT signalling emerging as the main tumor mechanism. Potential prognostic markers and therapeutic targets were further identified in CTCs from TNBC patients. This study demonstrates that CTCs from TNBC are tumorigenic and highlights CDXs as a unique tool to better understand TNBC biology and develop novel therapeutic approaches. [ABSTRACT FROM AUTHOR]