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Abstract Hypoxia-driven adenosinergic signaling suppresses antitumor immunity and enables many tumors to evade cancer immunotherapy. Alkaline phosphatase (ALP) contributes to this immunosuppression by hydrolyzing extracellular adenosine triphosphate (ATP) to adenosine. Rather than inhibiting this broadly essential enzyme, we exploit elevated ALP activity in tumors as a tumor-specific trigger for enzyme-instructed self-assembly (EISA). Using a potent naphthalene-capped phosphopeptide diester precursor (1P), which exhibits in vivo efficacy as a starting point, we designed and synthesized a series of analogs (2P–15P) that vary the N-terminal capping group and/or the position of the phosphotyrosine trigger to explore structure–activity relationships. We evaluated these analogs for anticancer activity in ALP-overexpressing cancer cells (e.g., Saos-2), using ALP-low cells (e.g., HEK-293) as controls. One analog (6P) exhibited potent, selective cytotoxicity, with submicromolar GI50 values (∼0.3 μM) in ALP-high cancer cells. Notably, 6P demonstrated submicromolar GI90 values and surpassed the efficacy of cisplatin and paclitaxel against Saos-2 cells. These findings highlight the potential of rationally designed d-phosphopeptide diesters to enable ALP-responsive self-assembly and selectively inhibit the growth of ALP-overexpressing tumors. This strategy offers a promising platform for the development of supramolecular therapeutics targeting immunosuppressive tumor microenvironments. 

Abstract The Golgi apparatus is a central hub for protein trafficking and signaling, yet its rapid imaging and cell-selective disruption remain challenging. Here, we report cycling molecular assemblies (CyMA) for fast Golgi imaging and cell-selective interference. CyMA precursors are acetylated amphiphilic thiopeptides that traverse plasma membrane and are deacetylated by intracellular thioesterases. This exposes thiols that undergo palmitoylation by Golgi-resident palmitoyl acyltransferases utilizing palmitoyl-CoA. The resulting palmitoylated peptides self-assemble into dynamic nanostructures (i.e., CyMA) localized at the Golgi. Their continuous, reversibleS-acylation enables near-instantaneous Golgi imaging. Replacing fluorophore with a biphenyl motif promotes CyMA accumulation and disrupts functions such as protein modifications, trafficking, and secretion, leading to cell death. This study establishes dynamic supramolecular assembly as an active and selective strategy for Golgi-targeting, pleiotropically interfering with Golgi functions, which may be applicable to targeting other organelles by utilizing alternative enzyme switches to enable kinetic trapping. 

Abstract A fragment‐based approach has proven successful in drug design and protein assemblies, yet its potential for constructing biomaterials from simple organic building blocks remains underexplored, particularly for self‐assembly in aqueous phases, where water disrupts intermolecular hydrogen bonding. To the best of our knowledge, this study introduces the first case of integrating fragments from self‐assembling molecules to design a small organic molecule that forms novel hierarchical nanotubes with polymorphism. The molecule's compact design incorporates three structural motifs derived from known nanotube assemblies, enabling a hierarchical assembly process: individual molecules with two conformations form dimers, which organize into hexameric units. These hexamers further assemble into nanotubes comprising 2‐, 5‐, and 6‐protofilament fibers. The nanofibers share a nearly identical asymmetric unit – a hexameric triangular plate – with similar axial and lateral interfaces. The lateral interface, involving interactions between phosphate groups and aromatic rings, exhibits plasticity, allowing slight rotational variations between adjacent units. This adaptability facilitates the formation of diverse nanofiber architectures, showcasing the flexibility of these systems in aqueous environments. By leveraging fragments of self‐assembling molecules, this work demonstrates a straightforward strategy that combines conformational flexibility and self‐assembling fragments to construct advanced supramolecular biomaterials from small organic building blocks in aqueous settings. 

Biphenyl-capped phosphopeptides instruct cell aggregation into spheroids, with minimal effective concentrations below 10 μM. Key factors driving morphogenesis include the self-assembly ability and dynamic shapeshifting of the peptide assemblies.