Herein, we report on the synthesis and characterization of ruthenium compounds with the general formula [RuCl(AA-H)(NO)(dppb]PF6, where AA = glycine (1), L-alanine (2), L-phenylalanine (3) and L-valine (4), and dppb = 1,4-bis(diphenylphosphine)butane. The complexes were characterized using elemental analysis, UV/Vis and infrared spectroscopies, 1H, 13C, 31P NMR techniques, and cyclic voltammetry. Furthermore, the structures of the compounds (1) and (3) were determined using single-crystal X-ray diffraction. In vitro evaluation of the Ru(II)/nitrosyl/amino acid complexes revealed their cytotoxic activities against triple-negative MDA-MB-231 breast cancer cells, and against the non-tumor murine fibroblast cells. All the compounds decreased the percentage of viable cells, inducing cell death by apoptosis. Additionally, the Ru(II) complexes inhibited the migration of MDA-MB-231 cells at concentrations lower than 35 µM, after 48 h of exposure. Thus, these complexes may be promising agents for the treatment of triple-negative MDA-MB-231 breast cancer.
Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest malignancies, with limited therapeutic options and a highly unfavorable prognosis, largely attributed to the presence of a desmoplastic tumor microenvironment. In this study, the photodynamic efficacy of metalloporphyrin-based photosensitizerspalladium(II)/diphosphine-coordinated meso-tetrapyridyl porphyrins, PS1 and PS2were evaluated in both homogeneous and heterogeneous 3D models of PDAC composed of MIA PaCa-2 tumor cells and pancreatic cancer-associated fibroblasts. Photodynamic therapy was conducted using red light (λ = 635 nm) at doses ranging from 1.5 to 10 J/cm2, following a 90 min of incubation period. Among the tested compounds, PS2 demonstrated superior photodynamic performance in both models, exhibiting significantly lower IC50 values compared to PS1, thereby indicating enhanced phototoxicity. At a concentration of 3 μM, the IC50 value for PS2 was 1.3 ± 0.1 J/cm2, whereas for PS1 exhibited a markedly higher IC50 of 5.7 ± 0.06 J/cm2. This enhanced efficacy was attributed to sustained, dose-dependent generation of reactive oxygen species and increased cellular uptake. Notably, treatment with PS2 induced calreticulin exposure on the cell surface, indicative of immunogenic cell death. Organelle-specific analyses revealed mitochondrial hyperpolarization and decreased lysosomal fluorescence, suggesting selective subcellular accumulation and functional impairment.