Serum EV-derived Small ubiquitin-like modifier 1 pseudogene 3 (SUMO1P3) was significantly elevated in Triple-Negative BC (TNBC), a subtype of BC.161 More importantly, this lncRNA also significantly decreased in chemosensitive patients after therapy, and high EV SUMO1P3 was associated with poor prognosis. The gene discussed is SUMO1P3; the disease is breast cancer.