Nrg2, a member of the neuregulin family, belongs to the EGF family of growth factors. It contains a receptor-binding EGF-like domain and mediates binding to cellular receptors such as HER3, triggering intracellular signaling cascades involved in cell growth, differentiation, and migration [1,4,6].

In prostate regeneration, mesenchymal cells can drive the process partly through androgen-driven expression of Nrg2, which acts in a paracrine fashion on luminal cells [2]. In gliomas, Nrg2 is expressed to varying extents and promotes the migration of glioma cells in vitro, suggesting that targeting Nrg2 signaling may reverse glioma cell metastasis [3]. In breast cancer, the down-regulation of Nrg2 is related to poor survival rate. Knockdown of Nrg2 promotes the proliferation, invasion, and migration of breast cancer cells, indicating it may act as a tumor suppressor factor [5]. In non-small cell lung cancer (NSCLC), Nrg2 fusions enhance ectopic expression of the NRG/ErbB receptor-ligand, and are considered novel markers for biological therapy targeting ErbB2/ErbB3 [4].

In conclusion, Nrg2 plays essential roles in multiple biological processes and disease conditions. Its functions in processes like tissue regeneration and in diseases such as gliomas, breast cancer, and NSCLC have been revealed through various studies. Understanding Nrg2 provides insights into disease mechanisms and potential therapeutic targets for these diseases.