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In our study, we aimed to develop a codelivery nanoparticulate system of pirarubicin (THP) and paclitaxel (PTX) (Co-AN) using human serum albumin to improve the therapeutic effect and reduce systemic toxicities. The prepared Co-AN demonstrated a narrow size distribution around 156.9 ± 3.2 nm (PDI = 0.16 ± 0.02) and high loading efficiency (87.91 ± 2.85% for THP and 80.20 ± 2.21% for PTX) with sustained release profiles. Significantly higher drug accumulation in tumors and decreased distribution in normal tissues were observed for Co-AN in xenograft 4T1 murine breast cancer bearing BALB/c mice. Cytotoxicity test against 4T1 cells in vitro and antitumor assay on 4T1 breast cancer in vivo demonstrated that the antitumor effect of Co-AN was superior to that of the single drug or free combination. Also, Co-AN induced increased apoptosis and G2/M cell cycle arrest against 4T1 cells compared to that of the single drug formulation. Remarkably, Co-AN exhibited significantly lower side effects regarding bone marrow suppression and organ and gastrointestinal toxicities. This human serum albumin-based codelivery system represents a promising platform for combination chemotherapy in breast cancers.

Chemoimmunotherapy‐induced antitumor immune response is highly dependent on tumor autophagy. When tumor cells are treated with chemoimmunotherapy, timely overactivated autophagy can not only lead more tumor cells to death, but also participate in the endogenous antigen presentation and immune stimulators secretion of dying cells, thus plays a vital role. However, timely and accurately overactivated tumor autophagy during chemoimmunotherapy is of great difficulty. Here, an on‐demand autophagy cascade amplification nanoparticle (ASN) is reported to boost oxaliplatin‐induced cancer immunotherapy. ASN is prepared by self‐assemble of autophagy‐responsible C‐TFG micelle and is followed by electrostatic binding of oxaliplatin prodrug (HA‐OXA). After entering tumor cells, the HA‐OXA shell of ASN first responds to the reduction microenvironment and releases oxaliplatin to trigger tumor immunogenic cell death and mildly stimulates tumor autophagy. Then, the exposed C‐TFG micelle can sensitively respond to oxaliplatin‐induced autophagy and release a powerful autophagy inducer STF‐62247, which precisely transforms autophagy to “overactivated” condition, leading tumor cells to autophagic death and enhance subsequent tumor antigen processing of the dying cells. In CT26 tumor‐bearing mice, ASN exhibits optimal immune stimulation and antitumor efficiency due to its on‐demand autophagy induction ability.

A new strategy for the construction of the compounds with two different heterocycles, linked by a C(2)-tether via a domino process involving [5 + 1] annulation, ring-opening, and subsequent double isocyanide cyclization, from the reaction of ethyl isocyanoacetate with divinyl ketones (DVKs) has been developed. The chemoselective fragmentation of the cyclohexanone intermediate is the key for the formation of not only the C(2)-tether but also the two different heterocycles.

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