MALDI-MS Patterning of Caspase Activities and Its Application in the Assessment of Drug Resistance.
Mass spectrometry (MS) has been widely used for enzyme activity assays. Herein, we propose a MALDI-MS patterning strategy for the convenient visual presentation of multiple enzyme activities with an easy-to-prepare chip. The array-based caspase-activity patterned chip (Casp-PC) is fabricated by hydrophobically assembling different phospholipid-tagged peptide substrates on a modified ITO slide. The advantages of amphipathic phospholipids lead to high-quality mass spectra for imaging analysis. Upon the respective cleavage of these substrates by different caspases, such as caspase-1, -2, -3, and -8, to produce a mass shift, the enzyme activities can be directly evaluated by MALDI-MS patterning by m/z-dependent imaging of the cleavage products. The ability to identify drug-sensitive/resistant cancer cells and assess the curative effects of anticancer drugs is demonstrated, indicating the applicability of the method and the designed chip.
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China.
Junjie
J
Hu
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China.
Fei
F
Liu
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, P.R. China. hxju@nju.edu.cn.
Huangxian
H
Ju
D000970:Antineoplastic Agents / Q000494:pharmacology / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D061945:Caspase Inhibitors / Q000737:chemistry / Q000378:metabolism; D020169:Caspases / Q000737:chemistry / Q000378:metabolism*; D019008:Drug Resistance, Neoplasm; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D061986:MCF-7 Cells; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D010455:Peptides / Q000737:chemistry / Q000378:metabolism; D010714:Phosphatidylethanolamines / Q000737:chemistry / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013379:Substrate Specificity; D017971:Tin Compounds / Q000737:chemistry
D000970:Antineoplastic Agents; D061945:Caspase Inhibitors; D010455:Peptides; D010714:Phosphatidylethanolamines; D017971:Tin Compounds; C038089:1,2-distearoylphosphatidylethanolamine; C109984:indium tin oxide; D020169:Caspases
MALDI-MS; caspases; enzymes; high-throughput screening; mass spectrometry