Increased CD70 expression is associated with clinical resistance to cisplatin-based chemotherapy and poor survival in advanced ovarian carcinomas

Naifu Liu,^1,* Xiugui Sheng,^1,* Yi Liu,¹ Xiaoling Zhang,¹ Jinming Yu<sup>2

1</sup>Department of Gynecologic Oncology, Shandong Cancer Hospital and Institute, Jinan, Shandong, People’s Republic of China; ²Shandong Cancer Hospital and Institute, Jinan, Shandong, People’s Republic of China

^*These authors contributed equally to this work

Background: CD70 has been regarded as a novel potential therapeutic target for multiple cancers. In this study, we characterized the expression of the CD70 protein in ovarian carcinomas and assessed its clinical-pathological prognostic value.
Materials and methods: The expression of CD70 in advanced ovarian cancer specimens was assessed by immunohistochemistry. Our results indicated that 16 out of 92 (17.4%) advanced ovarian serous carcinoma tumors showed a high level of CD70 expression. Furthermore, CD70 overexpression was significantly associated with cisplatin-based chemotherapy responses. The high CD70 expression subgroup demonstrated a higher incidence of chemotherapy resistance than the low CD70 subgroup (68.8% versus 25.0%, P = 0.001). Furthermore, univariate analysis conducted on subsets of ovarian carcinoma indicated that high CD70 expression was also associated with decreased survival rates; retained significance was observed on multivariate analysis.
Conclusion: Given the elevated expression of CD70 and its relationship with drug resistance and poor prognosis, our findings suggest that a minor proportion of ovarian carcinomas with CD70 overexpression might be a candidate for the emerging anti-CD70 antibody drug conjugates or therapeutic anti-CD70 antibodies.

Keywords: ovarian carcinoma, CD70, immunohistochemistry, survival, chemotherapy resistance