In the present study we correlated the genetic constitution of breast cancer patients expressed by polymorphic variants of two SUMO-specific cysteine proteases − SENP1 and SENP2, with clinical parameters of patients, including lymph node status, tumor grade, hormone receptors (estrogen and progesterone receptors) and epidermal growth factor receptor 2 (HER2) expressions. The gene discussed is SENP1; the disease is breast cancer.