Interactions of platinum and ruthenium coordination complexes with pancreatic phospholipase A(2) and phospholipids investigated by MALDI TOF mass spectrometry

Analytical Platforms for the Determination of Phospholipid Turnover in Breast Cancer Tissue: Role of Phospholipase Activity in Breast Cancer Development

Altered lipid metabolism has been associated with the progression of various cancers, and aberrant expression of enzymes involved in the lipid metabolism has been detected in different stages of cancer. Breast cancer (BC) is one of the cancer types known to be associated with alterations in the lipid metabolism and overexpression of enzymes involved in this metabolism. It has been demonstrated that inhibition of the activity of certain enzymes, such as that of phospholipase A₂ in BC cell lines sensitizes these cells and decreases the IC₅₀ values for forthcoming therapy with traditional drugs, such as doxorubicin and tamoxifen. Moreover, other phospholipases, such as phospholipase C and D, are involved in intracellular signal transduction, which emphasizes their importance in cancer development. Finally, BC is assumed to be dependent on the diet and the composition of lipids in nutrients. Despite their importance, analytical approaches that can associate the activity of phospholipases with changes in the lipid composition and distribution in cancer tissues are not yet standardized. In this review, an overview of various analytical platforms that are applied on the study of lipids and phospholipase activity in BC tissues will be given, as well as their association with cancer diagnosis and tumor progression. The methods that are applied to tissues obtained from the BC patients will be emphasized and critically evaluated, regarding their applicability in oncology.

Biological activity and binding properties of [Ru(II)(dcbpy)2Cl2] complex to bovine serum albumin, phospholipase A2 and glutathione

Ruthenium compounds are highly regarded as metallo-drug candidates. Many studies have focused their attention on the interaction between ruthenium complexes with their possible biological targets. The interaction of ruthenium complexes with transport proteins, enzymes and peptides is of great importance for understanding their biodistribution and mechanism of action, therefore, the development of an anti-cancer therapy involving ruthenium complexes has recently shifted from DNA targeting towards protein targeting. With the aim of gaining insight into possible interactions between ruthenium complexes with biologically relevant proteins, we have studied the interaction of cis-dichlorobis(2,2'-bipyridyl-4,4'-dicarboxylic acid)ruthenium(II) complex [Ru(II)(dcbpy)2Cl2], which previously showed good potency in photo-dynamic chemotherapy, with bovine serum albumin (BSA), phospholipase A2 (PLA2) and glutathione (GSH). Binding constants and possible number of binding sites to mentioned proteins and peptide are investigated by ultraviolet-visible spectroscopy and Matrix-Assisted Laser Desorption Ionization Mass Spectrometry (MALDI TOF MS). The complex binding affinities were in the following order: PLA2 > BSA > GSH. Moreover, genotoxic profile of the complex, tested on peripheral blood lymphocytes as a model system, was also promising.