Despite extensive research, the molecular role of AGR2 in the progression and metastasis of colorectal cancer (CRC) has not been fully characterized. We used quantitative mass spectrometry (SWATH MS) to identify differentially expressed proteins in paired CRC cell models of the SW480 and SW620 cell lines in response to AGR2 protein level manipulation. Relying on the results from SWATH MS and subsequent immunochemical validation, we selected NMP3 as the top candidate protein associated with AGR2 in CRC tumour cells in our screen. RT‒qPCR and immunochemical analysis confirmed the involvement of AGR2-mediated regulation of NPM3 at the transcriptional and posttranscriptional levels. Since PD-L1 is a constituent of the NPM3 regulatory axis, we aimed to correlate the changes in PD-L1 to the differential expression of AGR2 in our cell models. We found that AGR2 positively regulates PD-L1 levels in both SW480 and SW620 cell lines; additionally, several different CRC patient transcriptome cohorts confirmed the association of AGR2 with PD-L1. Our work reveals a new AGR2-NPM3 regulatory axis and the involvement of AGR2 in the regulation of PD-L1, which paves the way for the association of AGR2 with immune evasion in CRC cells.

• Keywords
• AGR2, Colorectal cancer, NPM3, PD-L1,
• MeSH
• B7-H1 Antigen * metabolism   genetics   MeSH
• Nuclear Proteins metabolism   genetics   MeSH
• Colorectal Neoplasms * genetics   metabolism   pathology   MeSH
• Humans MeSH
• Mucoproteins * metabolism   genetics   MeSH
• Cell Line, Tumor MeSH
• Nucleophosmin * MeSH
• Oncogene Proteins * metabolism   genetics   MeSH
• Proteins * metabolism   genetics   MeSH
• Gene Expression Regulation, Neoplastic * MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• AGR2 protein, human MeSH Browser
• B7-H1 Antigen * MeSH
• CD274 protein, human MeSH Browser
• Nuclear Proteins MeSH
• Mucoproteins * MeSH
• NPM3 protein, human MeSH Browser
• Nucleophosmin * MeSH
• Oncogene Proteins * MeSH
• Proteins * MeSH

CHIP is an E3-ubiquitin ligase that contributes to healthy aging and has been characterized as neuroprotective. To elucidate dominant CHIP-dependent changes in protein steady-state levels in a patient-derived human neuronal model, CHIP function was ablated using gene-editing and an unbiased proteomic analysis conducted to compare knock-out and wild-type isogenic induced pluripotent stem cell (iPSC)-derived cortical neurons. Rather than a broad effect on protein homeostasis, loss of CHIP function impacted on a focused cohort of proteins from actin cytoskeleton signaling and membrane integrity networks. In support of the proteomics, CHIP knockout cells had enhanced sensitivity to induced membrane damage. We conclude that the major readout of CHIP function in cortical neurons derived from iPSC of a patient with elevate α-synuclein, Parkinson's disease and dementia, is the modulation of substrates involved in maintaining cellular "health". Thus, regulation of the actin cytoskeletal and membrane integrity likely contributes to the neuroprotective function(s) of CHIP.

• Keywords
• bioinformatics, cell biology, omics, organizational aspects of cell biology, proteomics,
• Publication type
• Journal Article MeSH