pladienolide B

**Pladienolide B** is a natural macrolide compound isolated from *Streptomyces platensis* and is a potent, selective inhibitor of the spliceosome, specifically targeting the **splicing factor 3B subunit 1 (SF3B1)**. It inhibits pre-mRNA splicing by binding to SF3B1, leading to global splicing impairment, cell cycle arrest (at G1 and G2/M), and induction of apoptosis. Pladienolide B demonstrates high antitumor activity in vitro and in vivo against a range of cancers including gastric cancer, chronic lymphocytic leukemia, ovarian, cervical, hepatocellular, glioblastoma, and lymphoid tumors, often at nanomolar concentrations. Preclinically, it also reprograms pluripotent stem cells and alters the immune microenvironment, notably increasing cytotoxic immune cell infiltration in tumors. Pladienolide B serves as a research tool and a chemical lead for analog drugs (e.g., E7107, H3B-8800). No evidence supports its human clinical use or approval, and clinical analogs have encountered toxicity issues, especially vision loss[1][2][3][4][5][6][7].

Other names

PBpladienolide B