Objective: In the present work, we report for the first time the therapeutic potential of talazoparib
(BMN 673)-SLNs for the treatment of BRCA1 deficient Triple Negative Breast Cancer (TNBC).
BMN 673-SLNs were produced by hot-homogenization technique and then characterized.
Methods: The cytotoxic and apoptotic effects of BMN 673-SLNs compared with BMN 673 were determined
on HCC1937BRCA1-/-, HCC1937-R resistant TNBC and MCF-10A control cell lines. BMN 673-
SLNs were found to have reduced particle size (219.5 ± 1.45 nm) and thus more stable (-28.4 ± 2.52
mV) than BMN 673 (1652 ± 2.46 nm and -18.6 ± 0.45 mV) at 4°C.
Results: In vitro cell line studies demonstrated that BMN 673-SLNs showed significant cytotoxic effects
on HCC1937 (29.8%) and HCC1937-R cells (35.7%) at 10 nM for 12 days compared with BMN 673
(HCC1937 cells: 34.0% and HCC1937-R cells: 93.8% at 10 nM for 12 days) (p<0.05). Additionally,
BMN 673-SLNs (40.1%) reduced the toxicity of BMN 673 (53.1%) on MCF-10A control cells thanks to
unique physical properties.
Conclusion: The apoptotic rates in the 10 nM BMN 673-SLNs treatment (88.78% and 85.56%) for 12
days were significantly higher than those in 10 nM BMN 673 (82.6% and 25.86%) for 12 days in HCC1937
and HCC1937-R cells, respectively (p<0.01). Furthermore, these effects were consistent with the findings
of colony formation, wound healing and calcein accumulation analysis. In conclusion, the therapeutic potential
of BMN 673-SLNs provides a promising chemotherapeutic strategy for the treatment of drugresistant