Inhibition of MAGEA2 regulates pluripotency, proliferation, apoptosis, and differentiation in mouse embryonic stem cells

Circular RNAs in stem cells: from basic research to clinical implications

Circular RNAs (circRNAs) are a special class of endogenous RNAs with a wide variety of pathophysiological functions via diverse mechanisms, including transcription, microRNA (miRNA) sponge, protein sponge/decoy, and translation. Stem cells are pluripotent cells with unique properties of self-renewal and differentiation. Dysregulated circRNAs identified in various stem cell types can affect stem cell self-renewal and differentiation potential by manipulating stemness. However, the emerging roles of circRNAs in stem cells remain largely unknown. This review summarizes the major functions and mechanisms of action of circRNAs in stem cell biology and disease progression. We also highlight circRNA-mediated common pathways in diverse stem cell types and discuss their diagnostic significance with respect to stem cell-based therapy.

Overexpression of melanoma-associated antigen A2 has a clinical significance in embryonal carcinoma and is associated with tumor progression

INTRODUCTION

Melanoma-associated antigen A2 (MAGE-A2) is a member of the cancer-testis antigen family differentially overexpressed in a variety of malignancies and is associated with tumor development. However, clinical significance and prognostic value of MAGE-A2 in different histological subtypes of testicular germ cell tumors (TGCTs) have not been explored.

MATERIALS AND METHODS

Here, we aimed to investigate the clinical significance and prognostic impact of MAGE-A2 expression in TGCTs compared to benign tumors as well as adjacent normal tissues and then between seminomas and non-seminomas groups using immunohistochemistry on tissue microarrays.

RESULTS

The results indicated a statistically significant difference between overexpression of MAGE-A2 and histological subtypes of TGCTs. A statistically significant association was found between a high level of nuclear expression of MAGE-A2 protein and advanced pT stage (P = 0.022), vascular invasion (P = 0.037), as well as involvement of rete testis (P = 0.022) in embryonal carcinomas. Increased nuclear expression of MAGE-A2 was observed to be associated with more aggressive behaviors and tumor progression rather than cytoplasmic expression in these cases. Further, high level nuclear expression of MAGE-A2 had shorter disease-specific survival (DSS) or progression-free survival (PFS) compared to patients with moderate and low expression of MAGE-A2, however, without a statistically significant association.

CONCLUSION

Our results confirm that increased nuclear expression of MAGE-A2 has a clinical significance in embryonal carcinomas and is associated with progression of disease. Moreover, MAGE-A2 may act as a potential predictive biomarker for the prognosis in embryonal carcinomas if follow-up period becomes longer. Further investigations for the biological function of MAGE-A2 are required in future studies.