Xiaowen (Kevin) Liu, PhD

Xiaowen (Kevin) Liu, PhD

Professor

As a bioinformatician with expertise in computational proteomics, I have the training, experience, and expertise

to perform the proposed research project. I have more than 19 years of experience in bioinformatics algorithm

design, software development, and data analysis. During the last 15 years, my research is focused on mass

spectrometry (MS)-based computational proteomics. I have extensive data analysis experience in peptide and

protein identification, quantification, post-translational modification (PTM) identification and de novo sequencing

by top-down and bottom-up MS and published more than 70 papers in this area. I designed and developed

TopPIC suite, the most widely used open-source software package for proteoform identification by top- down MS,

and CHAMPS and TBNovo, two software tools for whole protein sequencing using MS. Collectively, these tools

have been downloaded more than 7000 times by researchers around the world and have been applied to study

various cell systems, such as cardiac muscle cells and cancer cells. I collaborated with leading proteomics

laboratories on MS-related studies, such as Pacific Northwest National Laboratory and Dr. Liang liang Sun at

Michigan State University. I identified a proteomics biomarker in Bronchiolitis Obliterans Syndrome using bottom up

MS and carried out MS-based qualitative and quantitative proteomics studies and systems biology studies of

several diseases, such as diabetes and colorectal cancer. Collaborating with Dr. Sun, we performed the first

proteome-level comparative study of proteoforms in metastatic and non-metastatic colorectal cells (McCool et

al., Science Advances, 2022).

I am a PI of an active NCI grant titled “Quantitative top-down proteomics of human colorectal

cancer cells and tumors” (R01CA247863 2/2021 – 1/2026). The aim of the project is to develop

highly sensitive mass spectrometry-based systems for top-down proteomics, gain new insights

into the colorectal cancer (CRC) metastasis through quantitative top-down proteomics of two

isogenic CRC cell lines (SW480 and SW620), and understand Lynch Syndrome at the proteoform

level via quantitative top-down proteomics of patients’ tumor samples.

The genome level and transcriptome-level information cannot accurately reflect the protein-level

information because post-transcriptional regulation can modulate protein expression and because

post-translational modifications (PTMs) can influence protein function. Quantitative proteomic

studies of CRC are vital. Many bottom-up proteomics studies have been completed on CRC cells

and tumors, but limited information on proteoforms have been acquired due to low protein

sequence coverages typically obtained from bottom-up proteomics. Different proteoforms from

the same gene can have drastically different functions. We hypothesize that large-scale and

quantitative top-down proteomics of human CRC cells and tumors will provide new insights into

CRC, leading to better therapies.

In this project, we develop new analytical tools to boost the sensitivity and scale of top-down

proteomics. The new tools will enable large-scale and quantitative top-down proteomics of CRC

cells before and after metastasis as well as CRC tumors from patients with Lynch Syndrome. The

novel analytical tools will boost the sensitivity of top-down proteomics by tenfold and will be

particularly useful for the proteomics community for large-scale top-down proteomics of mass limited

samples. Quantitative top-down proteomics of CRC cells before and after metastasis will

generate an unprecedented resource for the cancer biology community to gain new insights into

CRC metastasis. Quantitative top-down proteomics of the Lynch Syndrome tissues will elucidate

the roles played by mutations and functions of DNA mismatch repair genes in Lynch Syndrome

at the proteoform level.

LCRC Faculty

Michael D. Celestin Jr PhD
Population Sciences
LSU Health - New Orleans
Jean Christopher Chamcheu PhD
Translational Oncology
University of Louisiana Monroe
Andrew G. Chapple PhD
Population Sciences
LSU Health - New Orleans
YiPing Chen PhD
Cancer Biology
Tulane University School of Medicine
John Cole MD
Translational Oncology
Ochsner Health
Cathi Cox-Boniol
Population Sciences
Louisiana Tech University
Santosh D'Mello PhD
Translational Oncology
LSU Health - Shreveport
Srikanta Dash PhD
Cancer Biology
Tulane University School of Medicine
Heidi Davis, PhD
Population Sciences
Ochsner Health