The Proteomics Shared Resource (PRS) provides technical expertise and full proteomic services to the OSUCCC–James and the Ohio cancer research community.

PSR Director: Kari Green-Church, PhD

Research Scientist: Liwen Zhang, PhD

Senior Research Associate: Nan Kleinholz

Research Associate: Sasha Popova-Butler, PhD

Research Associate: Jocelyn Hach

Research Associate: Cindy James, PhD

Research Assistant: Mark Aspega

Systems Administrator: Andy Hall

Kari Green-Church, PhD, PSR director, is an expert on proteomics and mass spectrometry.
She manages the PSR operations, including coordinating collaborative research projects with OSUCCC–James members, overseeing staff, consulting with investigators and assisting OSUCCC–James members with grant proposals and publications.

Dr. Green-Church received her doctorate in chemistry from Louisiana State University, where she collaborated on the development of novel sample preparation methods for proteomic analysis of hydrophobic membrane proteins.

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Liwen Zhang, PhD, is a research scientist with the PSR who specializes in post-translational modification analyses while also providing technical expertise on numerous aspects of mass spectrometry and proteomics.

She has worked extensively in the detection of post-translational modifications, crosslink or amino acid mutation of proteins. In additional, Dr. Zhang also works on label free or isotope-labeling protein quantitation using mass spectrometry coupled with chromatography.

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Dr. Zhang received her doctorate in analytical chemistry from The Ohio State University, where she studied histone modifications using mass spectrometry.

Nan Kleinholz is the PSR’s senior research associate. She is not only a MALDI-TOF technical expert, but she is also an expert in chromatography – especially valuable for LC-MS/MS studies relevant to proteomics in which there are complex mixtures and the MS resolution is only as good as the initial LC separation.

Kleinholz also assists OSUCCC–James members with developing new chromatographic methods for 2D-capillary LC/MS/MS.

Prior to offering her expertise to the PRS and OSUCCC–James members, Kleinholz maintained a decade of industrial experience in the pharmaceutical industry.

Kleinholz received her Bachelor of Science in Medical Technology from the University of Dayton.

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Sasha Popova-Butler, PhD, a PSR research associate, offers expertise in differential gel electrophoresis for quantitative proteomic applications. She is active in protein structural biology research, and she assists investigators with protein labeling, 2D electrophoresis and the bioinformatics and statistical analysis of the changes in protein fold expression levels.

Currently, Dr. Popova-Butler is developing methods for the prefractionation of complex protein mixtures and the proteomic characterization of those fractions. Additionally, she is active in designing new prefractionation techniques and in the analysis of human fluid samples for biomarker analysis.  She received her doctorate in 1999 in Ecology from the Russian Academy of Science. 

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Jocelyn Hach, a PSR research associate who is an expert in processing proteomics samples, performs routine and advanced sample preparation, in-gel digestions, LC-MS preparation for proteomics studies and DIGE analyses for researchers. 

Hach is also responsible for traditional mass spectrometry applications including GC-MS, LC-MS and accurate mass analysis.

She received her Bachelor’s degree in 2006 majoring in Biology and Music performance. 

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Cindy James, PhD, a PSR research associate who has been active in research involving protein purification and characterization throughout her career, offers expertise in protein purification, 2D polyacrylamide gel separations and subsequent image analysis of the gels. 

Dr. James assists users in developing sample fractionation and extraction for improved gel electrophoresis methods utilized to separate important components prior to mass spectrometric analysis. She also is able to assist researchers with Western blot analysis, both 1D and 2D. 

She received her doctorate in biochemistry from The University of Akron in 2000.

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Mark Apsega,  a PSR Resarch assistant who recently received his Bachelor degree from Ohio Wesleyan University in 2009, with a major in biology. Mark is responsible for all the molecular weight analysis of small molecules by electrospray.  He measures the nominal or accurate mass of small molecule samples submitted. Mark also assists with protein sample preparation including in-gel digestions and solution phase digestions for protein ID experiments. 

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Andy Hall, the PSR systems administrator is responsible for all network and bioinformatic hardware. Bioinformatics are a critical aspect of high-throughput proteomics. The search files are approaching greater than GB size each and can take a week to search the database in some instances. Moving, disseminating and storing this data is critical to our operation and publication abilities.

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The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James) 460 W. 10th Avenue, Columbus, OH 43210 Phone: 1-800-293-5066 | Email: