Codelivery of TRAIL and Mitomycin C via Liposomes Shows Improved Antitumor Effect on TRAIL-Resistant Tumors.

Although tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) constitutes a promising antitumor drug, tumor resistance to TRAIL has become a major obstacle in its clinical application. Mitomycin C (MMC) is an effective TRAIL-resistant tumor sensitizer, which indicates a potential utility of combination therapy. However, the efficacy of this combination therapy is limited owing to its short half-life and the cumulative toxicity of MMC. To address these issues, we successfully developed a multifunctional liposome (MTLPs) with human TRAIL protein on the surface and MMC encapsulated in the internal aqueous phase to codeliver TRAIL and MMC. MTLPs are uniform spherical particles that exhibit efficient cellular uptake by HT-29 TRAIL-resistant tumor cells, thereby inducing a stronger killing effect compared with control groups. In vivo assays revealed that MTLPs efficiently accumulated in tumors and safely achieved 97.8% tumor suppression via the synergistic effect of TRAIL and MMC in an HT-29 tumor xenograft model while ensuring biosafety. These results suggest that the liposomal codelivery of TRAIL and MMC provides a novel approach to overcome TRAIL-resistant tumors.

Anticancer Effect of STING Agonist-Encapsulated Liposomes on Breast Cancer.

Breast cancer is one of the most common cancers worldwide, posing a serious threat to human health. Recently, innate immunity has become a widely discussed topic in antitumor research. The STING pathway is an important component of innate immunity, and several STING agonists have been developed and applied in antitumor research. Dimeric amidobenzimidazole (diABZI) is one STING agonist and is a nucleotide analog with low serological stability and cell membrane permeability. In this study, we prepared diABZI-encapsulated liposomes (dLNPs) using the ammonium sulfate gradient method. The average particle size of the dLNPs was 99.76 ± 0.230 nm, and the encapsulation efficiency was 58.29 ± 0.53%. Additionally, in vivo and in vitro assays showed that the dLNPs had a sustained-release effect and that the circulation time in vivo was longer than 48 h. The expression of IFN-ß and IFN-γ was elevated in mice treated with dLNPs. Moreover, we found that dLNPs can recruit CD8+ T cells to tumor tissue and exert antitumor effects. The dLNPs-treated group showed the most significant efficacy: the average tumor volume was 231.46 mm3, which decreased by 78.16% and 54.47% compared to the PBS group and diABZI group. Meanwhile, the hemolysis rate of the dLNPs was 2%, showing high biocompatibility. In conclusion, dLNPs can effectively suppress tumor growth and possess great potential in breast cancer therapy.

Increasing the antitumor efficacy of doxorubicin liposomes with coupling an anti-EGFR affibody in EGFR-expressing tumor models.

Epidermal growth factor receptor (EGFR) is overexpressed in a wide range of solid tumors. In this study, we exploited a high-affinity EGFR-antagonistic affibody (ZEGFR) coupled to a doxorubicin loaded pegylated liposome (LS-Dox) for concurrent passive and active targeting of EGFR+ A431 tumor cells in vitro and in vivo. The in vitro studies revealed that the Dox liposomes coupled with ZEGFR (AS-Dox) showed a higher Dox uptake than LS-Dox in EGFR+ A431 cells but not in EGFR- B16F10 cells, resulting in a selectively enhanced cytotoxicity. In vivo, AS-Dox confirmed its long circulation time and efficient accumulation in tumors. This targeted chemotherapy achieved greater tumor suppression. Further, this low-dose but effective targeted treatment reduced systemic toxicity such as body weight loss and organ injury demonstrated by H&E staining. Thus, selective targeting of LS-Dox coupled with ZEGFR enhanced antitumor effects and improved systemic safety. These results demonstrated that LS-Dox coupled with ZEGFR might be developed as a potential tool for therapy of EGFR+ tumors.