empesertib (BAY1161909)

Here, we extended those studies into syngeneic murine models of TNBC using two TTK inhibitors: empesertib and the novel TTK inhibitor CFI-402257 (also known as luvixasertib) that was recently granted FDA fast track approval in breast cancer. Taken together, these studies demonstrate that TTK inhibition enhances radiosensitivity and TTK inhibition with RT modulates the immune landscape of TNBC. Collectively, this combination may represent a novel therapeutic strategy to improve outcomes for patients with TNBC by both direct tumor cytotoxicity and by promoting an immune-responsive environment.

Interestingly, patients with high expression of SMAD3 exhibited significant resistance to dasatinib and staurosporine, while high sensitivity to tamoxifen and auranofin. In addition, SMAD3 knockdown promoted the apoptosis of BT-549 cells and decreased cell activity, and BAY-1161909 and XK-469 increased drug efficacy. In conclusion, genes of the SMAD family play a crucial role in the development of breast cancer.

Tumor growth was monitored and, following the completion of the study, final tumor weights were recorded and tumor tissue was collected to perform immunofluorescent microscopy. Single-agent TTK inhibition via treatment with the ATP-competitive inhibitor empesertib inhibits the growth of murine TNBC cell lines with IC50 values up to 30nM... Our data suggests that TTK inhibition and radiotherapy is synergistic in murine TNBC and alters the tumor immune microenvironment. This combined therapy suggests that changes in the underlying immune mechanisms as a result of the synergistic treatment efficacy are important in TNBC. Future work will examine the underlying mechanisms of TTK inhibition and radiotherapy on systemic and tumoral immune changes.