Background: The transcriptional factors E2F1 and E2F2 have been reported to be associated with improved chemosensitivity in various cancers. We aimed to investigate whether E2F1 and E2F2 can be used as predictors of chemosensitivity in hormone-receptor-negative breast cancers (HRNBCs), which are common in Korean women.
Methods: A total of 183 patients with primary breast cancer who had undergone surgical resection were evaluated on the basis of hormonal status, age, histological subtype and grade, tumor size, lymph node metastasis, and stage. The immunohistochemical expressions of E2F1 and E2F2 were analyzed for these histopathological data and patient survival.
Results: E2F1 expression was associated with low histological grade (grade 1) and larger tumor size (>2 cm), while E2F2 expression was correlated only with large tumor size (>2 cm). The E2F1-positive group had less tumor recurrences, lymph node metastases during follow-up, and distant metastases than the E2F1-negative group; E2F1 expression was found to be an independent predictive factor of more favorable survival among HRNBC patients on univariate and multivariate analyses, but E2F2 expression was not.
Conclusions: E2F1 may be a potential prognostic and predictive factor for clinical outcome and therapeutic results following adjuvant chemotherapy in HRNBC patients.