Caspase-independent apoptosis induction of quorum-sensing autoinducer analogs against chronic myeloid leukemia K562.

Quorum sensing is defined as the ability of microorganisms to sense their population density via the release of signaling molecules called autoinducers (AIs). Various types of AI analogs were prepared and their antitumor properties against chronic myeloid leukemia (CML) K562 cells were investigated. Two AI analogs induced progressive apoptosis with JNK activation and p21 induction. In addition, this induction of apoptosis is not related to bcr-abl kinase, which sustains CML proliferation. However, the progression of apoptosis was not inhibited by a caspase family inhibitor. These results suggested that AI analogs could induce caspase-independent apoptosis in CML K562.