BTF3 sustains cancer stem-like phenotype of prostate cancer via stabilization of BMI1

Abstract Background Cancer stem-like traits contribute to prostate cancer (PCa) progression and metastasis. Deciphering the novel molecular mechanisms underlying stem-like traits may provide important insight for developing novel therapeutics. Methods Immunohistochemistry and immunofluorescence assays in prostatic tissues; gain- and loss-of-function analyses using ectopic overexpression and shRNAs in PCa cell lines; measurements of tumorigenic and stemness properties, and transcription in vitro and in vivo; transcriptional analysis in public databases. Results We identified that overexpression of BTF3 in PCa tissues and BTF3 expression highly correlates to stem-like traits. Cancer stem-like characteristics in PCa including self-renewal and metastatic potential were impaired by BTF3 loss and promoted by BTF3 overexpression. Mechanistically, BTF3 could stabilize BMI1, which is a crucial regulator of prostate stem cell self-renewal. More importantly, our data revealed that BTF3 is highly predictive of poor prognosis and may help in risk stratification of PCa patients. Conclusions BTF3 promotes PCa progression though modeling stem-like traits in PCa. BTF3 represents a stratification marker in PCa progression and outcomes.