Single Cell Mass Spectrometry Quantification of Anticancer Drugs: Proof of Concept in Cancer Patients

Abstract

In clinical cancer medicine, the current inability to quantify intracellular chemotherapy drug concentrations in individual human cells limits the personalization and overall effectiveness of drug administration. New bioanalytical methods capable of real-time measurement of drug levels in live single cancer cells would allow for more adaptive and personalized administration of chemotherapy drugs, potentially leading to better clinical outcomes with fewer side effects. In this study, we report the development of a new quantitative single cell mass spectrometry (qSCMS) method capable of providing absolute drug amounts and concentrations in single cancer cells. Using this qSCMS system, quantitative analysis of the intracellular drug gemcitabine present in individual bladder cancer cells is reported, including in bladder cancer cells isolated from patients undergoing standard-of-care gemcitabine chemotherapy. The development of single cell pharmacology bioanalytical methods can potentially lead to more effective and safely administered drug medications in patients, especially in the treatment of cancer.

Metabolomics studies of cell–cell interactions using single cell mass spectrometry combined with fluorescence microscopy

“…Although quantitative Single-probe SCMS experiments can be performed to measure the absolute quantity or concentration of target molecules (e.g., anticancer drugs) in single cells, the internal standard (e.g., isotopically labelled anticancer drug) is needed in each study. 41,53 It is impractical to obtain the absolute quantitative information of large numbers of species from single cells. In our studies, ion intensities were normalized to the total ion current (TIC), a commonly used normalization method in MS studies, and then multiplied by an arbitrary scaling factor of 10 5 .…”

Introductory Chapter: A Tool for Aided Advanced Diagnostics and Deep View into Biological Sample

“…The significant rise in use of different MS approaches for clinical analyses correlates with improvements in ionization technologies, miniaturization of separation systems, notably of chromatographic systems (HPLC) [1], the significant and exciting improvements in sample preparation even of a single cell [2], and bioinformatic analysis. The mass spectrometry is applied for both "classical" clinical laboratory analyses and for analyzing samples for personalized and precision medicine.…”

Quantitation of amiodarone and N-desethylamiodarone in single HepG2 cells by single-cell printing-liquid vortex capture-mass spectrometry

“…To quantitatively measure intracellular concentrations, the total amount of the compound and the total cell volume need to be simultaneously measured. Several mass spectrometry (MS) techniques have been demonstrated to detect, and in some cases quantify, the absolute amounts of small compounds with single-cell resolution, including matrix-assisted laser desorption ionization MS (MALDI-MS) [8][9][10], secondary ion-MS(SIMS) [11][12][13], laser desorption/ionization MS (LDI-MS) [14][15][16][17], nano-desorption electrospray ionization (nano-DESI) [18], laser electrospray ionization MS (LAESI-MS) [19], laser ablation liquid vortex capture-MS (LA-LVC-MS) [20,21], and the single-probe [22][23][24][25]. However, only a few studies report direct measure of intracellular concentrations.…”

“…The 3D confocal image stack enables calculation of cell volume, while nanospray ionization MS of extracted cell contents resulted in quantitative detection of AMIO and NDEA yielding direct measure of intracellular concentration of AMIO and NDEA in single cells. Most recently, the single-probe technique was used to quantitate intracellular mass of anti-cancer drug gemcitabine in T24 bladder cancer cells and intracellular concentrations in single K562 leukemia cells [24]. However, the single-probe and nanopipette techniques are limited primarily by sampling throughput.…”

“…However, the single-probe and nanopipette techniques are limited primarily by sampling throughput. Even with automatic control < 100 cells were measured per experimental condition and in the case of patient samples, the total experiment needs to be conducted rapidly to avoid cellular degradation [24].…”