Attomole-per Cell Atomic Mass Spectrometry Measurement of Platinum and Gold Drugs in Cultured Lung Cancer Cells

• Published in: Molecules (Basel, Switzerland) Switzerland), 2021-12, Vol.26 (24), p.7627
• Main Authors: Jakubczak, Wioletta, Haczyk-Więcek, Maja, Pawlak, Katarzyna
• Format: Article
• Language: English
• Subjects: A549 Cells; Accumulation; Antineoplastic Agents - pharmacokinetics; Antineoplastic Agents - pharmacology; Atomic properties; auranofin; Auranofin - pharmacokinetics; Auranofin - pharmacology; Calcein; Cancer therapies; Carcinoma, Non-Small-Cell Lung - drug therapy; Carcinoma, Non-Small-Cell Lung - metabolism; Cell density; Chemotherapy; Cisplatin; Cisplatin - pharmacokinetics; Cisplatin - pharmacology; Cross flow; Cytosol; Cytotoxicity; Drugs; Efficiency; Enzymes; Gold; Humans; ICP-MS; Inductively coupled plasma mass spectrometry; Iodides; Lung cancer; Lung carcinoma; Lung Neoplasms - drug therapy; Lung Neoplasms - metabolism; Lysates; Mass Spectrometry; Mass spectroscopy; Metal concentrations; metal determination; Metal ions; Metallography; Metals; Methods; Non-small cell lung carcinoma; Oxidative stress; Platinum; Propidium iodide; Proteins; Selectivity; Transition metals
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules26247627

In this study, we developed a strategy to determine atto- and femtomolar amounts of metal ions in lysates and mineralizates of cells (human non-small-cell lung carcinoma (NSCLC, A549) and normal lung (MRC-5)) exposed to cytotoxic metallo-drugs: cisplatin and auranofin at concentrations close to the half-maximal inhibitory drug concentrations (IC ). The developed strategy combines data obtained using biological and chemical approaches. Cell density was determined using two independent cell staining assays using trypan blue, calcein AM/propidium iodide. Metal concentrations in lysed and mineralized cells were established employing a mass spectrometer with inductively coupled plasma (ICP-MS) and equipped with a cross-flow nebulizer working in aspiration mode. It allowed for detecting of less than 1 fg of metal per cell. To decrease the required amount of sample material (from 1.5 mL to ~100 µL) without loss of sensitivity, the sample was introduced as a narrow band into a constant stream of liquid (flow-injection analysis). It was noticed that the selectivity of cisplatin accumulation by cells depends on the incubation time. This complex is accumulated by cells at a lower efficiency than auranofin and is found primarily in the lysate representing the cytosol. In contrast, auranofin interacts with water-insoluble compounds. Despite their different mechanism of action, both metallo-drugs increased the accumulation of transition metal ions responsible for oxidative stress.