Affiliation:
1. new address Institute for Drug Discovery Leipzig University Leipzig Brüderstraße 34 04103 Germany
2. Faculty of Chemistry and Mineralogy Leipzig University Johannisallee 29 Leipzig 04103 Germany
3. Institute of Nuclear Sciences “Vinča” University of Belgrade 12-14 Mike Petrovića Street Belgrade 11351 Serbia
4. Department of Immunology Institute for Biological Research “Siniša Stanković” National Institute of Republic of Serbia Belgrade University Bul. despota Stefana 142 Belgrade 11060 Serbia
Abstract
AbstractTriple‐negative breast cancer (TNBC) poses challenges in therapy due to the absence of target expression such as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Frequently, the treatment of TNBC involves the combination of several therapeutics. However, an enhanced therapeutic effect can be also achieved within a single molecule. The efficacy of raloxifene can be improved by designing a raloxifene‐based hybrid drug bearing a 2,2’‐bipyridine moiety (2). Integration of platinum(II), palladium(II), and nickel(II) complexes into this structure dramatically changed the cytotoxicity. The platinum(II) dichloride complex 3 did not demonstrate any activity, while palladium(II) and nickel(II) dichloride complexes 4 and 5 exhibited various cytotoxic behavior towards different types of hormone‐receptor positive (HR+) cancer and TNBC cell lines. The replacement of the two chlorido ligands in 3–5 with a dicarbollide (carborate) ion [C2B9H11]2− resulted in reduced activity of compounds 6, 7, and 8. However, the palladacarborane complex 7 demonstrated higher selectivity towards TNBC. Furthermore, the mechanism of action was shifted from cytotoxic to explicitly cytostatic with detectable proliferation arrest and accelerated aging, characterized by senescence‐associated phenotype of TNBC cells. This study provides valuable insights into the development of hybrid therapeutics against TNBC.