Carmen (Amititeloaie) Gentimir, Gabriela Geleţu, Liliana Chelaru, Marcel Costuleanu
Aim of the study In cancer cells, NUR77/NR4A1 orphan receptors appear at the core of the functional picture as an oncogenic survival factor, however, it becomes a potent killer when certain activations of cell death phenomena occur. Material and methods The experimental studies we performed included the assessment of pro-B lymphocytes programmed death, induced as a result of activation of the NR4A1 orphan receptor, when treated with cytosporone A and gingival fibroblast-derived exosomes in the presence of apostatin 1, R-7050, and urolithin B. Results The real and distinguishable most important effects on apoptosis of pro-B lymphocytes, induced by cytosporone A, when also using exosomes liberated from gingival fibroblasts, were associated with the following reagents treatment: urolithin B, and R-7050. On the other hand, apostatin 1 had no significant effects when associated with cytospone A treatment. Conclusions So, inhibition of NF-κB pathway and of TNF-α receptors might increase the apoptotic degree induced by activation of NUR77/NR4A1 orphan receptors by cytosporone A, as well as the presence of exosomes derived from gingival fibroblasts. Moreover, the TRADD inhibition had no effects in the above conditions. The tumoral niche seems to be really of great importance when referring to the gingival tissue and leukemia precursors development.