Niklas Feuchter

Efficient delivery of CD80 mRNA by pBAE nanoparticles induces CD80 expression on tumor cells, enabling them to function as antigen-presenting cells and trigger CD8 ⁺ T cell–mediated anti-tumor immunity.

As cancer incidence continues to rise and conventional therapies remain of limited effectiveness, the search for novel and innovative cancer treatments is ongoing. In recent years, immunotherapies, including checkpoint inhibitors and cell-based approaches such as CAR-T cell therapy, have revolutionized the treatment of cancer. However, response rates even to well-established immunotherapies remain low in several types of cancer. Therefore, various novel immunomodulatory substances are currently under investigation, among them agonists of the intracellular signaling protein STING (STimulator of INterferon Genes). Activation of the STING signaling pathway can alter the cytokine profile within the tumor microenvironment (TME) and reshape the function of various immune cells. STING agonists have yielded promising results in preclinical studies, but this success has not yet been replicated in clinical trials. Consequently, STING agonists are optimized for greater potency and combined with nanotechnologies to enhance biodistribution and achieve sustained accumulation within the TME. This review summarizes a selection of STING agonists evaluated in clinical trials to date and discusses their effects on tumor-infiltration immune cells, especially macrophages. It highlights emerging candidates currently under investigation in preclinical studies, and explores nanotechnological approaches for their combinational use to enhance therapeutic efficacy.

Cancer remains one of the leading causes of death worldwide. New treatments like immunotherapy—especially checkpoint inhibitors and CAR-T cell therapy—have improved outcomes for some patients. However, these therapies often struggle to treat solid tumours effectively. Natural killer (NK) cells are part of the immune system and can naturally detect and destroy cancer cells without previous adaption. Scientists are now enhancing these cells by adding special receptors, called CARs (chimeric antigen receptors), to help them better recognize and attack cancer, an approach originally developed for T cells. CAR-NK cell therapy has some advantages over CAR-T therapy. It tends to cause fewer severe side effects, such as strong immune reactions or off-target effects in healthy tissues. Within some limitations, the allogenic use of CAR-NK cells is possible, as these cells exert less graft-versus-host activity. Such CAR-NK cell products can be produced in larger quantities and stored, making treatment more accessible. Still, there are challenges. It can be difficult to create enough modified NK cells, and the tumour microenvironment can block their activity. This review highlights recent progress in CAR-NK therapy, including early lab and clinical research. It also explores ways to improve these treatments and how they might work alongside other cancer therapies to help more patients in the future.