{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T18:23:01Z","timestamp":1785435781901,"version":"3.56.0"},"reference-count":50,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T00:00:00Z","timestamp":1775520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"NSFC","doi-asserted-by":"crossref","award":["U24A20803"],"award-info":[{"award-number":["U24A20803"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"NSFC","doi-asserted-by":"crossref","award":["22077009"],"award-info":[{"award-number":["22077009"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["U24A20803"],"award-info":[{"award-number":["U24A20803"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"award":["22077009"],"award-info":[{"award-number":["22077009"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100017610","name":"Shenzhen Science and Technology Innovation Program","doi-asserted-by":"crossref","award":["JCYJ20200109120408264"],"award-info":[{"award-number":["JCYJ20200109120408264"]}],"id":[{"id":"10.13039\/501100017610","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100017607","name":"Shenzhen Fundamental Research Program","doi-asserted-by":"crossref","award":["GXWD20201231165807007-20200811141635001"],"award-info":[{"award-number":["GXWD20201231165807007-20200811141635001"]}],"id":[{"id":"10.13039\/501100017607","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background\/Objectives: Cyclic dinucleotide stimulator of interferon genes (STING) agonists have emerged as potential agents in cancer immunotherapy, but their clinical applications are limited by relatively poor pharmacokinetic properties. Methods: A luciferase reporter assay was employed to screen delivery peptides capable of promoting cellular activating effect of cyclic dinucleotide STING agonists. The potent candidates were further confirmed by enzyme-linked immunosorbent assay (ELISA), real-time quantitative PCR (qPCR) and Western blotting analysis. Colon and melanoma cancer mouse models were used to examine the antitumor efficacy of the delivery peptides with cyclic GMP\u2013AMP (cGAMP) as a therapeutic agents or vaccine adjuvant. Results: We identify a class of STING agonist delivery peptides that efficiently facilitate cytosolic delivery of cyclic dinucleotide STING agonists and promote STING activation by forming peptide coacervates. Intratumoral administration of Sti3-4A and cGAMP effectively suppressed tumor growth and promoted antitumor immune response. Furthermore, the conjugation of tumor-specific antigen peptides with Sti3-4A promoted cytosolic co-delivery of antigen peptides and cGAMP, thus significantly boosting APC maturation, antigen cross-presentation, and T cell responses to peptide antigens. Prophylactic and therapeutic immunization with the conjugated peptides and cGAMP inhibited tumor growth in multiple murine tumor models. Conclusion: These findings establish STING agonist delivery peptides as a versatile platform for cancer immunotherapy.<\/jats:p>","DOI":"10.3390\/vaccines14040329","type":"journal-article","created":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T12:03:47Z","timestamp":1775563427000},"page":"329","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Peptide Coacervates Promote Cytosolic Delivery of STING Agonists for Cancer Immunotherapy"],"prefix":"10.3390","volume":"14","author":[{"given":"Wenlv","family":"Zheng","sequence":"first","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7039-7224","authenticated-orcid":false,"given":"Wei","family":"Tang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianzheng","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7318-0784","authenticated-orcid":false,"given":"Yurong","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shengnan","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dan","family":"Wu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-1947-6233","authenticated-orcid":false,"given":"Xiaoquan","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"},{"name":"Harold C. Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1601-6130","authenticated-orcid":false,"given":"Junmin","family":"Quan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Chemical Oncogenomics, Guangdong Key Laboratory of Chemical Genomics, Peking University Shenzhen Graduate School, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,4,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"674","DOI":"10.1038\/nature07317","article-title":"STING is an endoplasmic reticulum adaptor that facilitates innate immune signalling","volume":"455","author":"Ishikawa","year":"2008","journal-title":"Nature"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1629","DOI":"10.1038\/s41467-025-56407-7","article-title":"Cascaded immunotherapy with implantable dual-drug depots sequentially releasing STING agonists and apoptosis inducers","volume":"16","author":"Li","year":"2025","journal-title":"Nat. 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