Tumor suppressor PRELP membrane targets finally identified.

The interactome of membrane proteins are particularly interesting in cancer research as their involvement in pathways provide possible candidates for drug targets, as well as, understanding the molecular mechanisms involved in tumor growth and its regulation. Proline and arginine-rich end leucine-rich repeat protein (PRELP) has been previously implicated in tumor growth suppression. Furthermore, mRNA levels of PRELP have been shown to be downregulated in several cancers. However, the exact molecular mechanism has never been fully understood.

Other small leucine-rich proteoglycans (SLRPs) similar to PRELP regulate signalling pathways that modulate cell proliferation, adhesion, migration, and survival by directly interacting with several membrane protein receptors.

Kosuge et al. coupled coimmunoprecipitation with mass spectrometry (CoIP-MS) using IonOpticks Aurora Series columns to identify membrane proteins that interact with PRELP. Analysis of multiple samples showed possible interactions with several membrane proteins, most notable were two growth factor receptors: Insulin-like growth factor I receptor (IGFI-R), and low-affinity nerve growth factor receptor (p75NTR), which has been previously reported to have an anti-apoptotic function in breast cancer. PRELP’s interaction with these known growth factor receptors can explain its suppressive role in cancer cell growth.

In this study they also conducted a cell-based assay using recombinant PRELP transfected to A549 lung carcinoma cells that resulted in the suppression of cancer cell growth, as well as, micromolar changes in cell morphology.

Read the full paper
Proteomic Identification and Validation of Novel Interactions of the Putative Tumor Suppressor PRELP with Membrane Proteins Including IGFI-R and p75NTR.

J Biol Chem. 2021;100278.
doi: https://www.sciencedirect.com/science/article/pii/S0021925821000466

Kosuge, H., Nakakido, M., Nagatoishi, S., Fukuda, T., Bando, Y., Ohnuma, S. I., & Tsumoto, K. 

Commentary by Amr S Abbadi, PhD candidate.

About the author
Amr is a PhD candidate in comparative biomedical sciences at the University of Georgia, USA. He has also worked as a freelance writer and digital marketer for five years. Amr received his MSc in Pharmaceutical Biotechnology from the University of Padova in Italy, and graduated from the Suez Canal University in Egypt with a BSc in Clinical Pharmacy.