CHEK2 and ovarian cancer: In a study of immunohistochemistry involving 125 women with advanced stage HGSOC having a residual disease of less than 2 cm of cancer after surgery, it was shown that high expression of Chk2 was related to good response to platinum-based chemotherapy (OR = 0.132, p = 0.014) compared to those with low Chk2 expression in their pre-treated ovarian cancer tissues [38].