Poly Organotin Acetates against DNA with Possible Implementation on Human Breast Cancer

Two known tin-based polymers of formula {[R₃Sn(CH₃COO)] } where R = -Bu⁻ ( ) and R = Ph⁻ ( ),were evaluated for their in vitro biological properties. The compounds were characterized via their physical properties and FT-IR, Sn Mössbauer, and ¹H NMR spectroscopic data. The molecular structures were confirmed by single-crystal X-Ray diffraction crystallography. The geometry around the tin(IV) ion is trigonal bi-pyramidal. Variations in O⁻Sn⁻O···Sn' torsion angles lead to zig-zag and helical supramolecular assemblies for and , respectively. The in vitro cell viability against human breast adenocarcinoma cancer cell lines: MCF-7 positive to estrogens receptors (ERs) and MDA-MB-231 negative to ERs upon their incubation with and was investigated. Their toxicity has been studied against normal human fetal lung fibroblast cells (MRC-5). Compounds and exhibit 134 and 223-fold respectively stronger antiproliferative activity against MDA-MB-231 than cisplatin. The type of the cell death caused by or was also determined using flow cytometry assay. The binding affinity of and towards the CT-DNA was suspected from the differentiation of the viscosity which occurred in the solution containing increasing amounts of and . Changes in fluorescent emission light of Ethidium bromide (EB) in the presence of DNA confirmed the intercalation mode of interactions into DNA of both complexes and which have been ascertained from viscosity measurements. The corresponding apparent binding constants ( ) of and towards CT-DNA calculated through fluorescence spectra are 4.9 × 10⁴ ( ) and 7.3 × 10⁴ ( ) M respectively. Finally, the type of DNA binding interactions with and was confirmed by docking studies.