E2F1 as a molecular drug target in ovarian cancer

Ovarian cancer (OC) is the most lethal gynecological neoplasm in the world. From the histological point of view, OC is subdivided into type I and II [1]. Type I includes distinct tumor subtypes, i.e. low-grade serous carcinoma (LGSC), endometrioid carcinoma, clear cell carcinoma and mucinous carcinoma. Type II comprises high-grade serous cancer (HGSC), malignant mixed Mullerian tumors and high-grade endometroid ovarian carcinomas. Prognosis for type II is worse than for type I. For all OC cases, the combination of chemotherapy with surgery results in a five-year survival rate of only 45%; survival rate is further reduced to 25% for the very advanced forms. The limited survival descends from the fact that in the initial phases OC does not give a specific symptomatology, thus about 70% of the OC is diagnosed in an advanced phase when the efficacy of therapeutic options is modest. Moreover, in cases of recurrence, OC demonstrates a high resistance to chemotherapy. Thus, the identification of novel therapeutic strategies/molecular targets both for firstly diagnosed and for recurring OC forms is utmost urgent. Here, we focus on the description of the E2 promoter binding factor 1 (E2F1), a transcription factor relevant for the control of cell proliferation both in normal and tumor cells like OC cell