Long-lasting postoperative analgesia with local anesthetic-loaded hydrogels prevent tumor recurrence via enhancing CD8(+)T cell infiltration

Postoperative pain (POP) can promote tumor recurrence and reduce the cancer patient's quality of life. However, POP management has always been separated from tumor treatment in clinical practice, and traditional postoperative analgesia using opioids is still unsatisfactory for patients, which is not conducive to tumor treatment. Here, ropivacaine, a popular amide-type LA, was introduced into a Pluronic F127 hydrogel. Postoperative analgesia with ropivacaine-loaded hydrogels reduced the incidence of high-dose ropivacaine-induced convulsions and prolonged pain relief for more than 16 h. More interestingly, ropivacaine-loaded hydrogel was found to upregulate major histocompatibility complex class I (MHC-I) in tumor cells by impairing autophagy. Therefore, a hydrogel co-dopped with ropivacaine and TLR7 agonist imiquimod (PFRM) was rationally synthesized. After postoperative analgesia with PFRM, imiquimod primes tumor-specific CD8(+)T cells through promoting DCs maturation, and ropivacaine facilitates tumor cells recognition by primed CD8(+)T cells through upregulating MHC-I. Consequently, postoperative analgesia with PFRM maximumly increases CD8(+)T cells infiltration into residual tumor tissue and prevents tumor recurrence. Overall, this study for the first time provides an LA-based approach for simultaneous long-lasting postoperative analgesia and prevention of tumor recurrence. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12951-023-01803-8.