Pladienolide B is primarily used in biomedical research due to its potent biological activity as a splicing modulator. It targets the spliceosome, a complex responsible for processing precursor mRNA in eukaryotic cells. By binding to the SF3b subunit of the spliceosome, it disrupts normal RNA splicing, leading to the accumulation of incorrectly processed mRNA and ultimately inducing cell death, particularly in rapidly dividing cells.

This mechanism makes Pladienolide B a valuable tool in cancer research. It has shown strong antiproliferative effects against various tumor cell lines, including leukemia, melanoma, and solid tumors. Due to its high potency and specific mode of action, it serves as a lead compound for the development of novel anticancer agents. Derivatives of Pladienolide B, such as E7107, have entered clinical trials as potential therapeutics for certain cancers.

Additionally, it is used in molecular biology studies to investigate spliceosome function and RNA processing pathways. Its ability to precisely interfere with splicing makes it a critical molecule for understanding gene expression regulation and identifying vulnerabilities in cancer cells.