For example, Ki-67, STK15, Survivin, Cyclin B1, and MYBL2 have all been associated with breast cancer proliferation; Stromelysin 3 and Cathepsin L2 have been associated with invasion; and ER, PR, Bcl2, and SCUBE2 have been associated with responsiveness to Estrogen [47]. This evidence concerns the gene ESR1 and breast cancer.