Recent advances in sialic acid-based active targeting chemoimmunotherapy promoting tumor shed: a systematic review

Abstract

Tumors have always been a major public health concern worldwide, and the attempts looking for effective treatments have never ceased. Sialic acid is known as a crucial element for tumor development and its receptors are highly expressed on the tumor-associated immune cells, which perform significant roles in establishing immunosuppressive tumor microenvironment and further boosting tumorigenesis, progression, and metastasis. Obviously, it is essential to consider the sophisticated crosstalk among tumors, the immune system, and preparations, and understand the links between pharmaceutics and immunology. Sialic acid-based chemoimmunotherapy enables active targeting drug delivery via mediating the active recognition between sialic acid-modified nano-drug delivery system represented by liposomes and sialic acid-binding receptors on tumor-associated immune cells, which inhibits and utilizes their homing ability to deliver drugs. Such a “Trojan horse” strategy has remarkably improved the shortcomings of traditional passive targeting treatments, unexpectedly promoted tumor shed, and persistently induced robust immunological memory, illuminating the prospective application potential for various tumors. Herein, we review recent advances in sialic acid-based active targeting chemoimmunotherapy promoting tumor shed, summarize the current viewpoints of the tumor shed mechanism, especially the formation of durable immunological memory, and analyze the challenges and opportunities of this attractive approach.