Exosomes hold great potential in therapeutic development. However, native exosomes usually induce insufficient effects in vivo and simply act as drug delivery vehicles. Herein, we synthesize responsive exosome nano‐bioconjugates for cancer therapy. Azide‐modified exosomes derived from M1 macrophages are conjugated with dibenzocyclooctyne‐modified antibodies of CD47 and SIRPα (aCD47 and aSIRPα) through pH‐sensitive linkers. After systemic administration, the nano‐bioconjugates can actively target tumors through the specific recognition between aCD47 and CD47 on the tumor cell surface. In the acidic tumor microenvironment, the benzoic‐imine bonds of the nano‐bioconjugates are cleaved to release aSIRPα and aCD47 that can, respectively, block SIRPα on macrophages and CD47, leading to abolished “don't eat me” signaling and improved phagocytosis of macrophages. Meanwhile, the native M1 exosomes effectively reprogram the macrophages from pro‐tumoral M2 to anti‐tumoral M1.

Atherosclerosis (AS) is a major contributor to cardiovascular diseases worldwide, and alleviating inflammation is a promising strategy for AS treatment. Here, we report molecularly engineered M2 macrophage‐derived exosomes (M2 Exo) with inflammation‐tropism and anti‐inflammatory capabilities for AS imaging and therapy. M2 Exo are derived from M2 macrophages and further electroporated with FDA‐approved hexyl 5‐aminolevulinate hydrochloride (HAL). After systematic administration, the engineered M2 Exo exhibit excellent inflammation‐tropism and anti‐inflammation effects via the surface‐bonded chemokine receptors and the anti‐inflammatory cytokines released from the anti‐inflammatory M2 macrophages. Moreover, the encapsulated HAL can undergo intrinsic biosynthesis and metabolism of heme to generate anti‐inflammatory carbon monoxide and bilirubin, which further enhance the anti‐inflammation effects and finally alleviate AS. Meanwhile, the intermediate protoporphyrin IX (PpIX) of the heme biosynthesis pathway permits the fluorescence imaging and tracking of AS.

Purpose: To investigate the expression pattern and significance of DNA repair genes JWA and X-ray repair cross complement group 1 (XRCC1) in gastric cancer.Experimental Design: Expressions of JWA and XRCC1 were assessed by immunohistochemistry in a training cohort and they went into a second testing cohort and finally to a validating cohort. Prognostic and predictive role of JWA and XRCC1 expression status in cases treated with surgery alone or combined with adjuvant chemotherapy was evaluated, respectively.Results: JWA and XRCC1 protein levels were significantly downregulated in gastric cancer lesions compared with adjacent noncancerous tissues. Low tumoral JWA or XRCC1 expression significantly correlated with shorter overall survival (OS), as well as with clinicopathologic characteristics in patients without adjuvant treatment. Multivariate regression analysis showed that low JWA and XRCC1 expressions, separately and together, were independent negative markers of OS. Adjuvant fluorouracil-leucovorinoxaliplatin (FLO) significantly improved OS compared with surgery alone (log-rank test, P ¼ 0.01). However, this effect was evident only in the JWA or XRCC1 low expression group (HR ¼ 0.44; 95% CI: 0.26-0.73; P ¼ 0.002, and HR ¼ 0.44, 95% CI: 0.26-0.75; P ¼ 0.002, respectively); Adjuvant fluorouracilleucovorin-platinol (FLP) did not improve OS, except in the patients with low JWA and XRCC1 expressions (P ¼ 0.010 for JWA and 0.024 for XRCC1, respectively).Conclusions: JWA and XRCC1 protein expressions in tumor are novel candidate prognostic markers and predictive factors for benefit from adjuvant platinum-based chemotherapy (FLO or FLP) in resectable human gastric carcinoma.

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Extracellular vesicles (EVs) hold great potential in both disease treatment and drug delivery. However, accurate drug release from EVs, as well as the spontaneous treatment effect cooperation of EVs and drugs at target tissues, is still challenging. Here, an engineered self‐activatable photo‐EV for synergistic trimodal anticancer therapy is reported. M1 macrophage‐derived EVs (M1 EVs) are simultaneously loaded with bis[2,4,5‐trichloro‐6‐(pentyloxycarbonyl) phenyl] oxalate (CPPO), chlorin e6 (Ce6), and prodrug aldoxorubicin (Dox‐EMCH). After administration, the as‐prepared system actively targets tumor cells because of the tumor‐homing capability of M1 EVs, wherein M1 EVs repolarize M2 to M1 macrophages, which not only display immunotherapy effects but also produce H2O2. The reaction between H2O2 and CPPO generates chemical energy that activates Ce6, creating both chemiluminescence for imaging and singlet oxygen (1O2) for photodynamic therapy (PDT). Meanwhile, 1O2‐induced membrane rupture leads to the release of Dox‐EMCH, which is then activated and penetrates the deep hypoxic areas of tumors. The synergism of immunotherapy, PDT, and chemotherapy results in potent anticancer efficacy, showing great promise to fight cancers.