Alex M. Graça

Alex M. Graça

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Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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25 June 2023 in Inorganics
Verified
Journal Article
Open access
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MBMarília I. F. Barbosa
Marília I. F. Barbosa
Rodrigo S. CorreaRodrigo S. Correa
Rodrigo S. Correa
AGAdriana P. M. Guedes
Adriana P. M. Guedes
AGAlex M. Graça
Alex M. Graça
FMFrancyelli Mello-Andrade
Francyelli Mello-Andrade
ABAlzir Azevedo Batista
Alzir Azevedo Batista
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.

30 October 2025 in ACS Omega
Verified
Journal Article
Open access
EMEdynara Cruz de Moraes
Edynara Cruz de Moraes
LSLívia Do Carmo Silva
Lívia Do Carmo Silva
JCJuliana Santana de Curcio
Juliana Santana de Curcio
AGAlex M. Graça
Alex M. Graça
ABAlzir Azevedo Batista
Alzir Azevedo Batista
PGPablo Jose Goncalves
Pablo Jose Goncalves
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 photosensitizerspalladium­(II)/diphosphine-coordinated meso-tetrapyridyl porphyrins, PS1 and PS2were 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.