Targeted Proteomic Analysis of Cell Death Pathway Activation in Cancer Cell Lines

Although the human proteome is estimated to consist of up to 6,000,000 proteoforms, targeted interrogation of biological pathways at the protein level can deliver significantly greater quantitative accuracy and precision than non-targeted profiling.

Here we used an Agilent 6495C LC-MS/MS system and the MRM Proteomics PeptiQuant Plus kit to perform targeted analysis of 270 proteins in leukemia cells following treatment with the enzyme-drug L-asparaginase.

Key questions included:

• 1. Does the kit provide valuable information about cell death pathway activation?
• 2. Which modes of cell death are induced by L-asparaginase in ASNS-negative vs. ASNS-positive cell types?
• 3. Does resistance to L-asparaginase involve inactivation of specific cell death pathways?

The resulting data are expected to provide insight into mechanisms of L-asparaginase resistance.

Presenter: Philip Lorenzi, Ph.D. (Associate Professor, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center)

I’m an Associate Professor in the Department of Bioinformatics and Computational Biology at The University of Texas MD Anderson Cancer Center. My laboratory focuses on the development of metabolic therapies for the treatment of cancer (with an emphasis on nutrient metabolism), and I’m also Director of the Proteomics Core Facility and Director of the Metabolomics Core Facility. I’ve co-authored 71 peer-reviewed publications. I co-wrote and was Co-Investigator on a successfully completed $4.5M CPRIT Core Facility Award, managed staff and the budget, and oversaw development of bioanalytical services using current equipment and protocols that we have optimized thoroughly. We’ve developed novel mass spectrometry-based methods for: 1) increasing the accuracy of glutamine and glutamate measurements by minimizing in-source conversion to pyroglutamate; 2) normalizing data based on the DNA content of cell- and tissue-based samples; 3) measuring amino acids from as little as 2 µL of mouse plasma or whole blood; 4) detection of over 2,000 annotated metabolites and lipids per biological sample (including just 2 mg of tissue); 5) stable isotope tracer analyses in vitro and in vivo including methods for measuring energy metabolism; 6) determining the extent and position of 13C incorporation into specific amino acids; and 7) diagnosing and correcting batch effects in metabolomic data. Our multidisciplinary team provides full service contract research in a state-of-the art facility.