RRC ID 51761
Author Jayashree B, Srimany A, Jayaraman S, Bhutra A, Janakiraman N, Chitipothu S, Krishnakumar S, Baddireddi LS, Elchuri S, Pradeep T.
Title Monitoring of changes in lipid profiles during PLK1 knockdown in cancer cells using DESI MS.
Journal Anal Bioanal Chem
Abstract The importance of the polo-like kinase 1 (PLK1) gene is increasing substantially both as a biomarker and as a target for highly specific cancer therapy. This is due to its involvement in multiple points of cell progression and carcinogenesis. PLK1 inhibitors' efficacy in treating human cancers has been limited due to the lack of a specific targeting strategy. Here, we describe a method of targeted downregulation of PLK1 in cancer cells and the concomitant rapid detection of surface lipidomic perturbations using desorption electrospray ionization mass spectrometry (DESI MS). The efficient delivery of siRNA targeting PLK1 gene selectively to the cancer cells is achieved by targeting overexpressed cell surface epithelial cell adhesion molecule (EpCAM) by the EpDT3 aptamer. The chimeric aptamer (EpDT3-siPLK1) showed the knockdown of PLK1 gene expression and PLK1 protein levels by quantitative PCR and western blotting, respectively. The abundant surface lipids, phosphatidylcholines (PCs), such as PC(32:1) (m/z 754.6), PC(34:1) (m/z 782.6), and PC(36:2) (m/z 808.6), were highly expressed in MCF-7 and WERI-RB1 cancer cells compared to normal MIO-M1 cells and they were observed using DESI MS. These overexpressed cell surface lipids in the cancer cells were downregulated upon the treatment of EpDT3-siPLK1 chimera indicating a novel role of PLK1 to regulate surface lipid expression in addition to the efficient selective cancer targeting ability. Our results indicate that DESI MS has a potential ability to rapidly monitor aptamer-mediated cancer therapy and accelerate the drug discovery process. Graphical abstract Binding of aptamer chimera to the cells and changes in lipid profile.
Volume 408(20)
Pages 5623-32
Published 2016-8
DOI 10.1007/s00216-016-9665-y
PII 10.1007/s00216-016-9665-y
PMID 27277815
MeSH Cell Cycle Proteins / genetics Cell Cycle Proteins / metabolism* Gene Knockdown Techniques Humans Lipid Metabolism* Lipids / chemistry* MCF-7 Cells Neoplasms, Experimental / metabolism* Protein-Serine-Threonine Kinases / genetics Protein-Serine-Threonine Kinases / metabolism* Proto-Oncogene Proteins / genetics Proto-Oncogene Proteins / metabolism* Spectrometry, Mass, Electrospray Ionization / methods*
IF 3.286
Times Cited 3
Resource
Human and Animal Cells WERI-Rb-1(RCB2146)