CSDE1 Intracellular Distribution as a Biomarker of Melanoma Prognosis

Abstract

RNA-binding protein; Biomarker; Melanoma

Proteína de unión a ARN; Biomarcador; Melanoma

Proteïna d'unió a l'ARN; Biomarcador; Melanoma

RNA-binding proteins are emerging as critical modulators of oncogenic cell transformation, malignancy and therapy resistance. We have previously found that the RNA-binding protein Cold Shock Domain containing protein E1 (CSDE1) promotes invasion and metastasis of melanoma, the deadliest form of skin cancer and also a highly heterogeneous disease in need of predictive biomarkers and druggable targets. Here, we design a monoclonal antibody useful for IHC in the clinical setting and use it to evaluate the prognosis potential of CSDE1 in an exploratory cohort of 149 whole tissue sections including benign nevi and primary tumors and metastasis from melanoma patients. Contrary to expectations for an oncoprotein, we observed a global decrease in CSDE1 levels with increasing malignancy. However, the CSDE1 cytoplasmic/nuclear ratio exhibited a positive correlation with adverse clinical features of primary tumors and emerged as a robust indicator of progression free survival in cutaneous melanoma, highlighting the potential of CSDE1 as a biomarker of prognosis. Our findings provide a novel feature for prognosis assessment and highlight the intricacies of RNA-binding protein dynamics in cancer progression.

A.I. and P.E. were supported by PhD4MD fellowships from the CRG and the Emerald program (Marie Skłodowska-Curie grant agreement 101034290), respectively. This work was supported by the following grants to F.G.: PGC2018-099697-B-I00 and PID2021-127948NB-I00 from the Spanish Ministry of Science and Innovation (MCIN) funded by MCIN/ AEI /10.13039/501100011033/ and by ERDF; “la Caixa” Foundation (ID 100010434) under the Grant LCF/PR/HR17/52150016; the Catalan Agency for Research and Universities (SGR-Cat-2021-01215) and intramural funds from the CRG on emergent translational research. We acknowledge the support of the Spanish Ministry of Science and Innovation through the Centro de Excelencia Severo Ochoa (CEX2020-001049-S, MCIN/AEI /10.13039/501100011033) and the Generalitat de Catalunya through the CERCA programme.