A pan-cancer analysis of the prognosis and immune infiltration of eEF1A2 and its potential function in thyroid carcinoma.

ABSTRACT

Purpose: Eukaryotic translation elongation factor 1α2 (eEF1A2) promotes tumour progression in various cancers. We performed a pan-cancer analysis of eEF1A2 and explored its role in thyroid carcinoma (THCA). Methods: Databases from The Cancer Genome Atlas (TCGA), the University of Alabama at Birmingham Cancer data analysis Portal (UALCAN), and the Human Protein Atlas (HPA) were used to investigate the differential expression of eEF1A2 in pan-cancer. The pathological stage, prognostic characteristics, tumour microenvironment (TME), tumour mutational burden (TMB), and microsatellite instability (MSI) were analysed in diverse tumours with different expression levels of eEF1A2. The expression levels in papillary thyroid carcinoma (PTC) and its specific role in cell proliferation, migration, invasion, and cell glycolysis in PTC cells were verified by quantitative real time polymerase chain reaction (qRT-PCR), immunohistochemistry, cell counting kit-8, colony formation, wound healing, Transwell assay, and lactate acid and glucose assays.Results:eEF1A2 was differentially expressed in various malignant tumour tissues compared to control tissues and was associated with poor pathological stage and prognosis in most types of tumours. Moreover, eEF1A2 expression closely correlated with the infiltration of immunosuppressive cells, TMB, and MSI in some tumour types. Expression of eEF1A2 in PTC is higher than the para-carcinoma, and eEF1A2 downregulation suppressed TPC-1 and BCPAP cell proliferation, migration, invasion, and glycolysis. Conclusion: Our study suggests that the expression of eEF1A2 is related to the prognosis and immune infiltration of some tumours and may be a predictor of prognosis and immunotherapy. eEF1A2 could promote malignant behaviour of PTC cells.