Baicalein enhances immune response in TNBC by inhibiting leptin expression of adipocytes

Triple‐negative breast cancer (TNBC) is a special pathological type of breast cancer (BC) with poor prognosis. Obesity is shown to be involved in TNBC tumor progression. The interaction between obesity and BC has generated great attention in recent years, however, the mechanism is still unclear. Here, we showed that leptin secreted by adipocytes upregulated PD‐L1 expression in TNBC through the p‐STAT3 signaling pathway and that baicalein inhibited PD‐L1 expression in tumor microenvironment by suppressing leptin transcription of adipocytes. Collectively, our findings suggest that leptin may be the key factor participating in obesity‐related tumor progression and that baicalein can break through the dilemma to boost the anti‐tumor immune response.