Wen Liu | Developmental Cell: ER-localized JmjC domain-containing protein JMJD8 targets STING to promote immune evasion and tumor growth in breast cancer

Highlights

• ER-localized protein JMJD8 inhibits STING-induced type I IFN signaling pathway

• JMJD8 interacts with STING to disrupt the STING-TBK1 complex formation

• JMJD8 knockdown inhibits breast tumorigenesis by activating antitumor immunity

• JMJD8 knockdown improves chemotherapy and ICT effects in suppressing tumor growth

Summary

The STING-mediated type I interferon (IFN) signaling pathway has been shown to play critical roles in antitumor immunity. Here, we demonstrate that an endoplasmic reticulum (ER)-localized JmjC domain-containing protein, JMJD8, inhibits STING-induced type I IFN responses to promote immune evasion and breast tumorigenesis. Mechanistically, JMJD8 competes with TBK1 for binding with STING, blocking STING-TBK1 complex formation and restricting type I IFN and IFN-stimulated gene (ISG) expression as well as immune cell infiltration. JMJD8 knockdown improves the efficacy of chemotherapy and immune checkpoint therapy in treating both human and mouse breast cancer cell-derived implanted tumors. The clinical relevance is highlighted in that JMJD8 is highly expressed in human breast tumor samples, and its expression is inversely correlated with that of type I IFN and ISGs as well as immune cell infiltration. Overall, our study found that JMJD8 regulates type I IFN responses, and targeting JMJD8 triggers antitumor immunity.

Link: https://www.sciencedirect.com/science/article/pii/S1534580723001314