Furthermore, while survivin has been previously reported as a possible explanation for the mechanism of action of selinexor [3, 25], by testing a wide array of breast cancer cell lines in this study, we have shown that selinexor decreases XPO1 expression and survivin expression not only in selinexor-sensitive cell lines but also in selinexor-resistant lines. This evidence concerns the gene BIRC5 and breast carcinoma.