The transcription factor KLF4 as an independent predictive marker for pathologic complete remission in breast cancer neoadjuvant chemotherapy: a case–control study

BACKGROUND To identify whether a stem cell biomarker, KLF4, may predict the pathologic tumor response to neoadjuvant chemotherapy for patients with locally advanced breast cancer. METHODS Twelve locally advanced breast cancer patients who achieved pathologic complete remission (pCR) after neoadjuvant chemotherapy were identified and for each, three non-pCR breast cancer patients - matched for age, clinical tumor-node-metastasis stage, and neoadjuvant chemotherapy cycles - were selected. The relationship between KLF4 expression in the core needle biopsied cancer tissue and patient pCR rate was assessed using univariate and multivariate analysis. RESULTS Receiver operating characteristic curve analysis showed that the patients with a histoscore of KLF4 expression >0.18 had a lower pCR rate. Multivariable analysis showed that higher KLF4 expression (odds ratio 0.013; 95% confidence interval 0.013-0.444; P=0.004) was independently correlated with a lower pCR rate after neoadjuvant chemotherapy. CONCLUSION KLF4 overexpression was associated with lower pCR in locally advanced breast cancer patients undergoing neoadjuvant chemotherapy. This study suggests that KLF4 may serve as a predictor for pCR in patients with breast cancer after neoadjuvant chemotherapy.