Poly I:C-induced tumor cell apoptosis mediated by pattern-recognition receptors.

ABSTRACT

Poly IC is a synthetic dsRNA that can imitate a viral infection and elicit host immune responses by triggering specific pattern-recognition receptors (PRRs) such as toll-like receptor 3 and retinoic acid inducible gene I(RIG-I)-like receptors, including RIG-I and melanoma differentiation-associated gene 5. Activation of these PRRs by poly IC triggers a signal transduction cascade that results in the activation of NF-κB and production of type I interferon. Poly IC has been used as a vaccine adjuvant for cancer immunotherapy for several decades. Evidence from recent studies indicates that poly IC can directly induce apoptosis in several types of tumor cells, thus providing a new therapeutic approach for cancer treatment. However, the molecular mechanism underlying the induction of apoptosis by poly IC is still unclear. In this review, we summarize the current knowledge of poly IC-induced tumor cell apoptosis, focusing on the key molecules and pathways involved in this process.