NEAT1 is induced by estrogen and participates in transcription regulation by the FOXN3-NEAT1-SIN3A complex, transcriptional targeting of ERα by the FOXN3-NEAT1-SIN3A complex implies that there exists a negative-feedback loop in ERα+ breast cancer cells between ERα and the FOXN3-NEAT1-SIN3A complex, in which ERα transactivates NEAT1, which is assembled into the FOXN3-NEAT1-SIN3A complex, and this complex, in turn, transrepresses ERα. This evidence concerns the gene SIN3A and breast cancer.