Risk of colorectal cancer after appendectomy: A systematic review and meta-analysis.

BACKGROUND AND AIM: Appendectomy is associated with various diseases, but whether it increases the risk of colorectal cancer (CRC) remains uncertain. We conducted a systematic review and meta-analysis aimed at investigating the suggested correlation between appendectomy and CRC. METHODS: Systematic retrieval was performed using the PubMed, Embase, Cochrane library, Web of Science, and ClinicalTrials.gov databases up to May 4, 2022, for studies reported the influence of appendectomy on CRC, colon cancer (CC) or rectal cancer (RC). Odd ratios (ORs) and 95% confidence intervals (CIs) of CRC after appendectomy were pooled using the random effects model. Subgroup analyses were carried on by region, sex, and tumor location. RESULTS: Our search identified 1743 articles, of which 22 studies from three continents published between 1964 and 2022 were eligible for inclusion. Overall, people with appendectomy had a higher risk of CRC (OR = 1.31; 95% CI [1.05, 1.62]). But the risk for Europeans was not significant (OR = 0.94; 95% CI [0.87, 1.02]; I2  = 0%), while for Americans and Asians, appendectomy would increase the risk of CRC (OR = 1.68; 95% CI [1.15, 2.44]; I2  = 65% and OR = 1.46; 95% CI [1.04, 2.05]; I2  = 98%), especially in females and in developing countries. It is worth noting that appendectomy might be a protective factor for CC in European women (OR = 0.87; 95% CI [0.77, 0.98]; I2  = 0%). CONCLUSIONS: Appendectomy may be a risk factor for CRC, with varying degrees in different populations. More high-quality cross-regional studies are needed for better clinical decision making.

Noninvasive predictive models based on lifestyle analysis and risk factors for early-onset colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) incidence has increased among patients aged <50 years. Exploring high-risk factors and screening high-risk populations may help lower early-onset CRC (EO-CRC) incidence. We developed noninvasive predictive models for EO-CRC and investigated its risk factors. METHODS: This retrospective multicenter study collected information on 1756 patients (811 patients with EO-CRC and 945 healthy controls) from two medical centers in China. Sociodemographic features, clinical symptoms, medical and family history, lifestyle, and dietary factors were measured. Patients from one cohort were randomly assigned (8:2) to two groups for model establishment and internal validation, and another independent cohort was used for external validation. Multivariable logistic regression, random forest, and eXtreme Gradient Boosting (XGBoost) were performed to establish noninvasive predictive models for EO-CRC. Some variables in the model influenced EO-CRC occurrence and were further analyzed. Multivariable logistic regression analysis yielded adjusted odd ratios (ORs) and 95% confidence intervals (CIs). RESULTS: All three models showed good performance, with areas under the receiver operator characteristic curves (AUCs) of 0.82, 0.84, and 0.82 in the internal and 0.78, 0.79, and 0.78 in the external validation cohorts, respectively. Consumption of sweet (OR 2.70, 95% CI 1.89-3.86, P < 0.001) and fried (OR 2.16, 95% CI 1.29-3.62, P < 0.001) foods ≥3 times per week was significantly associated with EO-CRC occurrence. CONCLUSION: We established noninvasive predictive models for EO-CRC and identified multiple nongenetic risk factors, especially sweet and fried foods. The model has good performance and can help predict the occurrence of EO-CRC in the Chinese population.

Dual-binding nanoparticles improve the killing effect of T cells on solid tumor.

Adoptive cell therapy (ACT) was one of the most promising anti-tumor modalities that has been confirmed to be especially effective in treating hematological malignancies. However, the clinical efficacy of ACT on solid tumor was greatly hindered by the insufficient tumor-infiltration of cytotoxic CD8 + T cells. Herein, we constructed a nanoplatform termed dual-binding magnetic nanoparticles (DBMN) that comprised PEG-maleimide (Mal), hyaluronic acid (HA) and Fe3O4 for adoptive T cell-modification and ACT-sensitization. After a simple co-incubation, DBMN was anchored onto the cell membrane (Primary linking) via Michael addition reaction between the Mal and the sulfhydryl groups on the surface of T cells, generating magnetized T cells (DBMN-T). Directed by external magnetic field and in-structure Fe3O4, DBMN-T was recruited to solid tumor where HA bond with the highly expressed CD44 on tumor cells (Secondary Linking), facilitating the recognition and effector-killing of tumor cells. Bridging adoptive T cells with host tumor cells, our DBMN effectively boosted the anti-solid tumor efficacy of ACT in a mouse model and simultaneously reduced toxic side effects.

Immune Cell Connection by Tunneling Nanotubes: The Impact of Intercellular Cross-Talk on the Immune Response and Its Therapeutic Applications.

Direct intercellular communication is an important prerequisite for the development of multicellular organisms, the regeneration of tissue, and the maintenance of various physiological activities. Tunnel nanotubes (TNTs), which have diameters of approximately 50-1500 nm and lengths of up to several cell diameters, can connect cells over long distances and have emerged as one of the most important recently discovered types of efficient communication between cells. Moreover, TNTs can also directly transfer organelles, vehicles, proteins, genetic material, ions, and small molecules from one cell to adjacent and even distant cells. However, the mechanism of intercellular communication between various immune cells within the complex immune system has not been fully elucidated. Studies in the past decades have confirmed the existence of TNTs in many types of cells, especially in various kinds of immune cells. TNTs display different structural and functional characteristics between and within different immunocytes, playing a major role in the transmission of signals across various kinds of immune cells. In this review, we introduce the discovery and structure of TNTs, as well as their different functional properties within different immune cells. We also discuss the roles of TNTs in potentiating the immune response and their potential therapeutic applications.

Regulating immune memory and reversing tumor thermotolerance through a step-by-step starving-photothermal therapy.

BACKGROUND: Photothermal therapy (PTT) is a highly effective treatment for solid tumors and can induce long-term immune memory worked like an in situ vaccine. Nevertheless, PTT inevitably encounters photothermal resistance of tumor cells, which hinders therapeutic effect or even leads to tumor recurrence. Naïve CD8+ T cells are mainly metabolized by oxidative phosphorylation (OXPHOS), followed by aerobic glycolysis after activation. And the differentiate of effector CD8+ T cell (CD8+ Teff) into central memory CD8+ T cell (CD8+ TCM) depends on fatty acid oxidation (FAO) to meet their metabolic requirements, which is regulated by adenosine monophosphate activated protein kinase (AMPK). In addition, the tumor microenvironment (TME) is severely immunosuppressive, conferring additional protection against the host immune response mediated by PTT. METHODS: Metformin (Met) down-regulates NADH/NADPH, promotes the FAO of CD8+ T cells by activating AMPK, increases the number of CD8+ TCM, which boosts the long-term immune memory of tumor-bearing mice treated with PTT. Here, a kind of PLGA microspheres co-encapsulated hollow gold nanoshells and Met (HAuNS-Met@MS) was constructed to inhibit the tumor progress. 2-Deoxyglucose (2DG), a glycolysis inhibitor for cancer starving therapy, can cause energy loss of tumor cells, reduce the heat stress response of tumor cell, and reverse its photothermal resistance. Moreover, 2DG prevents N-glycosylation of proteins that cause endoplasmic reticulum stress (ERS), further synergistically enhance PTT-induced tumor immunogenic cell death (ICD), and improve the effect of immunotherapy. So 2DG was also introduced and optimized here to solve the metabolic competition among tumor cells and immune cells in the TME. RESULTS: We utilized mild PTT effect of HAuNS to propose an in situ vaccine strategy based on the tumor itself. By targeting the metabolism of TME with different administration strategy of 2DG and perdurable action of Met, the thermotolerance of tumor cells was reversed, more CD8+ TCMs were produced and more effective anti-tumor was presented in this study. CONCLUSION: The Step-by-Step starving-photothermal therapy could not only reverse the tumor thermotolerance, but also enhance the ICD and produce more CD8+ TCM during the treatment.

Inhibiting Hypoxia and Chemotherapy-Induced Cancer Cell Metastasis under a Valid Therapeutic Effect by an Assistance of Biomimetic Oxygen Delivery.

Tumor metastasis is the most dangerous stage in tumorigenesis and its evolution, which causes about 80% clinical death. However, common therapies including chemotherapy may increase the risk of tumor metastasis while killing cancer cells. Tumor metastasis is closely related to many factors in the tumor microenvironment, especially hypoxia. As one of the characteristics of a malignant tumor microenvironment, hypoxia plays an important role in the growth, metabolism, and metastasis of tumors. Upregulation of the hypoxia-inducible factor (HIF) would stimulate the metastasis and migration of cancer cells. In this study, we developed an artificial oxygen carrier system, a hemoglobin-loaded liposome (Hb@lipo), which was capable of effectively delivering oxygen to tumor. The way of providing oxygen not only alleviated tumor hypoxia but also downregulated the expression of HIF, which is conducive to reducing tumor malignancy. Alleviating the tumor hypoxic microenvironment alone is not enough to inhibit tumor metastasis; thus, we prepared the liposome containing a chemotherapeutic agent cabazitaxel (CBZ@lipo). Our data indicated that the combination therapy of Hb@lipo and CBZ@lipo can efficiently kill cancer cells and inhibit tumor growth. At the same time, it can effectively entrap cancer cells in tumor sites by relieving the hypoxic microenvironment of tumors and reduce the metastasis of cancer cells during and after the chemotherapy. Our research may provide a clinical cancer chemotherapy reference that reduces the risk of cancer cell metastasis while inhibiting tumor growth.

Identification of Three Novel Ring Expansion Metabolites of KAE609, a New Spiroindolone Agent for the Treatment of Malaria, in Rats, Dogs, and Humans.

KAE609 [(1'R,3'S)-5,7'-dichloro-6'-fluoro-3'-methyl-2',3',4',9'-tetrahydrospiro[indoline-3,1'-pyridol[3,4-b]indol]-2-one] is a potent, fast-acting, schizonticidal agent being developed for the treatment of malaria. After oral dosing of KAE609 to rats and dogs, the major radioactive component in plasma was KAE609. An oxidative metabolite, M18, was the prominent metabolite in rat and dog plasma. KAE609 was well absorbed and extensively metabolized such that low levels of parent compound (≤11% of the dose) were detected in feces. The elimination of KAE609 and metabolites was primarily mediated via biliary pathways (≥93% of the dose) in the feces of rats and dogs. M37 and M23 were the major metabolites in rat and dog feces, respectively. Among the prominent metabolites of KAE609, the isobaric chemical species, M37, was observed, suggesting the involvement of an isomerization or rearrangement during biotransformation. Subsequent structural elucidation of M37 revealed that KAE609, a spiroindolone, undergoes an unusual C-C bond cleavage, followed by a 1,2-acyl shift to form a ring expansion metabolite M37. The in vitro metabolism of KAE609 in hepatocytes was investigated to understand this novel biotransformation. The metabolism of KAE609 was qualitatively similar across the species studied; thus, further investigation was conducted using human recombinant cytochrome P450 enzymes. The ring expansion reaction was found to be primarily catalyzed by cytochrome P450 (CYP) 3A4 yielding M37. M37 was subsequently oxidized to M18 by CYP3A4 and hydroxylated to M23 primarily by CYP1A2. Interestingly, M37 was colorless, whereas M18 and M23 showed orange yellow color. The source of the color of M18 and M23 was attributed to their extended conjugated system of double bonds in the structures.

KAE609 (Cipargamin), a New Spiroindolone Agent for the Treatment of Malaria: Evaluation of the Absorption, Distribution, Metabolism, and Excretion of a Single Oral 300-mg Dose of [14C]KAE609 in Healthy Male Subjects.

KAE609 [(1'R,3'S)-5,7'-dichloro-6'-fluoro-3'-methyl-2',3',4',9'-tetrahydrospiro[indoline-3,1'-pyridol[3,4-b]indol]-2-one] is a potent, fast-acting, schizonticidal agent in clinical development for the treatment of malaria. This study investigated the absorption, distribution, metabolism, and excretion of KAE609 after oral administration of [(14)C]KAE609 in healthy subjects. After oral administration to human subjects, KAE609 was the major radioactive component (approximately 76% of the total radioactivity in plasma); M23 was the major circulating oxidative metabolite (approximately 12% of the total radioactivity in plasma). Several minor oxidative metabolites (M14, M16, M18, and M23.5B) were also identified, each accounting for approximately 3%-8% of the total radioactivity in plasma. KAE609 was well absorbed and extensively metabolized, such that KAE609 accounted for approximately 32% of the dose in feces. The elimination of KAE609 and metabolites was primarily mediated via biliary pathways. M23 was the major metabolite in feces. Subjects reported semen discoloration after dosing in prior studies; therefore, semen samples were collected once from each subject to further evaluate this clinical observation. Radioactivity excreted in semen was negligible, but the major component in semen was M23, supporting the rationale that this yellow-colored metabolite was the main source of semen discoloration. In this study, a new metabolite, M16, was identified in all biologic matrices albeit at low levels. All 19 recombinant human cytochrome P450 enzymes were capable of catalyzing the hydroxylation of M23 to form M16 even though the extent of turnover was very low. Thus, electrochemistry was used to generate a sufficient quantity of M16 for structural elucidation. Metabolic pathways of KAE609 in humans are summarized herein and M23 is the major metabolite in plasma and excreta.

Anti-angiogenic therapy in ovarian cancer: Current understandings and prospects of precision medicine.

Ovarian cancer (OC) remains the most fatal disease of gynecologic malignant tumors. Angiogenesis refers to the development of new vessels from pre-existing ones, which is responsible for supplying nutrients and removing metabolic waste. Although not yet completely understood, tumor vascularization is orchestrated by multiple secreted factors and signaling pathways. The most central proangiogenic signal, vascular endothelial growth factor (VEGF)/VEGFR signaling, is also the primary target of initial clinical anti-angiogenic effort. However, the efficiency of therapy has so far been modest due to the low response rate and rapidly emerging acquiring resistance. This review focused on the current understanding of the in-depth mechanisms of tumor angiogenesis, together with the newest reports of clinical trial outcomes and resistance mechanism of anti-angiogenic agents in OC. We also emphatically summarized and analyzed previously reported biomarkers and predictive models to describe the prospect of precision therapy of anti-angiogenic drugs in OC.

Precisely Regulating M2 Subtype Macrophages for Renal Fibrosis Resolution.

Macrophages are central to the pathogenesis of kidney disease and serve as an effective therapeutic target for kidney injury and fibrosis. Among them, M2-type macrophages have double-edged effects regarding anti-inflammatory effects and tissue repair. Depending on the polarization of the M2 subtypes (M2a or M2c) in the diseased microenvironment, they can either mediate normal tissue repair or drive tissue fibrosis. In renal fibrosis, M2a promotes disease progression through macrophage-to-myofibroblast transition (MMT) cells, while M2c possesses potent anti-inflammatory functions and promotes tissue repair, and is inhibited. The mechanisms underlying this differentiation are complex and are currently not well understood. Therefore, in this study, we first confirmed that M2a-derived MMT cells are responsible for the development of renal fibrosis and demonstrated that the intensity of TGF-ß signaling is a major factor determining the differential polarization of M2a and M2c. Under excessive TGF-ß stimulation, M2a undergoes a process known as MMT cells, whereas moderate TGF-ß stimulation favors the polarization of M2c phenotype macrophages. Based on these findings, we employed targeted nanotechnology to codeliver endoplasmic reticulum stress (ERS) inhibitor (Ceapin 7, Cea or C) and conventional glucocorticoids (Dexamethasone, Dex or D), precisely modulating the ATF6/TGF-ß/Smad3 signaling axis within macrophages. This approach calibrated the level of TGF-ß stimulation on macrophages, promoting their polarization toward the M2c phenotype and suppressing excessive MMT polarization. The study indicates that the combination of ERS inhibitor and a first-line anti-inflammatory drug holds promise as an effective therapeutic approach for renal fibrosis resolution.

Rational administration sequencing of immunochemotherapy elicits powerful anti-tumor effect.

As a research hotspot, immune checkpoint inhibitors (ICIs) is often combined with other therapeutics in order to exert better clinical efficacy. To date, extensive laboratory and clinical investigations into the combination of ICIs and chemotherapy have been carried out, demonstrating augmented effectiveness and broad application prospects in anti-tumor therapy. However, the administration of these two treatment modalities is usually randomized or fixed to a given chronological order. Nevertheless, the pharmacological effect of drug is closely related to its exposure behavior in vivo, which may consequently affect the synergistic outcomes of a combined therapy. In this study, we prepared a lipid nanoparticle encapsulating docetaxel (DTX-VNS), and associated it with the immune checkpoint inhibitor anti-PD-1 antibody (αPD-1) for the treatment of malignant tumors. To identify the optimum timing and sequencing for chemotherapy and immunotherapy, we designed three administration regimes, including the simultaneous delivery of DTX-VNS and αPD-1(DTX-VNS@αPD-1), DTX-VNS delivery before (DTX-VNS plus αPD-1) or post (αPD-1 plus DTX-VNS) PD-1 blockade with an interval of two days. Analysis from mass spectrometry, multi-factor detection and other techniques indicated that DTX-VNS plus αPD-1 initiated a powerful anti-tumor response in multiple tumor models, contributing to a remarkably reshaped tumor microenvironment landscape, which may attribute to the maximum therapeutic additive effects arise from a concomitant exposure of DTX-VNS and αPD-1 at the tumor site. By profiling the exposure kinetics of nanoparticles and αPD-1 in vivo, we defined the administration schedule with utmost therapeutic benefits, which may provide a valuable clinical reference for the rational administration of immunochemotherapy.

Targeted regulation of lymphocytic ER stress response with an overall immunosuppression to alleviate allograft rejection.

Transplantation is the most effective, and sometimes the only resort for end-stage organ failure. However, allogeneic graft suffers greatly from lymphocyte-mediated immunorejection, which bears close relationship with a hyperactivation of endoplasmic reticulum (ER) stress response in host lymphocytes, especially in CD8+ T cells (T-8). Therefore, regulating lymphocytic ER unfolded protein response (UPR) might be a potential therapeutic breakthrough in alleviating graft rejection. Here, ER-targetable liposome is prepared via the surface modification of ER-targeting peptide (Pardaxin), which efficiently loads and directly delivers small molecule inhibitor of UPR sensor IRE1α into the ER of lymphocytes, inducing a systemic immunosuppression that facilitates tumorigenesis and metastasis in the tumor inoculation challenge in vivo. And in vitro, a stage-differential dependency of IRE1α in the phase transition of T-8 is identified. Specifically, inhibiting IRE1α at the early responding stages of T-8, especially at the activation phase, results in a shrunk proliferation, impaired effector function, and limited memory commitment, which might contribute centrally to the induced overall immunosuppression. Based on this, a classical acute rejection model, murine full-thickness trunk skin allograft that primary arises from the hyperactivity of T-lymphocyte, is used. Results suggest that lymphocytic IRE1α inactivation attenuates transplant rejection and prolongs graft survival, with a limited effector function and memory commitment of host T-8. Moreover, an even higher immunosuppressive effect is obtained when IRE1α inhibition is used in combination with immunosuppressant tacrolimus (FK506), which might owe to a synergistic regulation of inflammatory transcription factors. These findings provide a deeper insight into the biological polarization and stress response of lymphocytes, which might guide the future development of allogeneic transplantation.

A clinically acceptable strategy for sensitizing anti-PD-1 treatment by hypoxia relief.

The hypoxic tumor microenvironment (TME) hinders the effectiveness of immunotherapy. Alleviating tumor hypoxia to improve the efficacy of immune checkpoint inhibitors (ICIs) represented by programmed cell death protein 1 (PD-1) antibody has become a meaningful strategy. In this study, we adopted three methods to alleviate hypoxia, including direct oxygen delivery using two different carriers and an indirect way involving HIF-1α inhibition. Both in vivo and in vitro experiments showed that liposomes modified with perfluorocarbon or hemoglobin (PFC@lipo or Hb@lipo) were able to efficiently load and release oxygen, relieving tumor hypoxia. However, the gas release behavior of PFC@lipo was uncontrollable, which might induce acute hyperoxia side effects during intravenous injection and reduce its biosafety. In contrast, whether administered locally or systemically, Hb@lipo revealed high animal tolerance, and was much safer than commercial HIF-1α inhibitor (PX-478), displaying prospects as a promising oxygen carrier for clinical practice. Pharmacodynamic experiments suggested that Hb@lipo helped PD-1 antibody break the therapeutic bottleneck and significantly inhibited the progression of 4 T1 breast cancer. But in CT26 colon cancer, the combination therapy failed to suppress tumor growth. After in-depth analysis and comparison, we found that the ratio of M1/M2 tumor associated macrophages (TAMs) between these two tumor models were dramatically different. And the lower M1/M2 ratio in CT26 tumors limited the anti-tumor effect of combination therapy. In this study, three methods for alleviating tumor hypoxia were compared from the perspectives of biosafety, efficacy and clinical applicability. Among them, Hb@lipo stood out, and its combined use with PD-1 antibody exhibit a distinct synergistic suppression effect on tumors with more M1 macrophages presented in the microenvironment. Our work provided a good reference for improving the efficacy of PD-1 antibody by alleviating tumor hypoxia.

Perdurable PD-1 blockage awakes anti-tumor immunity suppressed by precise chemotherapy.

The application of nanocarriers as drug delivery system for chemotherapeutic drugs has become a research hotspot in cancer treatment. Chemotherapy with high tumor-targeting accuracy and drug release specificity is the key to improve the efficacy of tumor chemotherapy and reduce the side effects caused by repeated doses drugs. Here, we synthesized a redox-sensitive nano-micelle formed by hyaluronic acid (HA) conjugated with d-α-tocopherol succinate (TOS) using a disulfide bond as the linker (HA-SS-TOS, HSST), which could actively accumulate to the tumor sites and metastasis cancer cells with high expression of CD44. The micelles could dissociate under the high GSH level in cancer cells, triggering a release of paclitaxel (PTX). Surprisingly, the precise chemotherapy instead induced a suppressive tendency of immune system, manifested by a significant increase in TGF-ß, which weakened the therapeutic effect of micelles. Moreover, the high levels of TGF-ß might be related to the increased drug-resistance of cancer cells. Research has shown that PD-1 pathway blockade can result in reduction in TGF-ß expression, thus, a PLGA microsphere encapsulating PD-1 antagonist peptides A12 (A12@PLGA) was further prepared to activate the host immune response. Our data indicated that PTX-loaded HSST could accurately "find" the tumors as well as metastasis cancer cells, and efficiently kill most of them. The joining of a durable PD-1 blockage significantly boosted the efficacy of PTX@HSST on multiple tumor models, including lung metastatic tumors and even multidrug-resistant tumors. Thus, our work presented an optimal chemo-immunotherapy combined system, which shows profound significance for future cancer therapy in clinic.

A Vaccination with Boosted Cross Presentation by ER-Targeted Antigen Delivery for Anti-Tumor Immunotherapy.

Vaccination is a widely-accepted resort against the invasion or proliferation of bacteria, parasites, viruses, and even cancer, which accounts heavily on an active involvement of CD8+ T cells. As one of the pivotal strategies taken by dendritic cells (DCs) to promote the responsiveness of CD8+ T cells to exogenous antigens, cross presentation culminates in an elevated overall host defense against cancer or infection. However, the precise mechanisms regulating such a process remains elusive, and current attempts to fuel cross presentation usually fail to exert efficiency. Here, model antigen OVA-loaded, endoplasmic reticulum (ER)-targeting cationic liposome (OVA@lipoT) is developed and characterized with a booster effect on the activation and maturation of DCs. Moreover, OVA@lipoT pulsed DCs exhibit overwhelming superiority in triggering cytotoxic T lymphocyte response both in vivo and in vitro. Data reveal that lipoT alters the intracellular trafficking and presenting pathway of antigen, which promotes cross presentation and bears close relationship to the ER-associated degradation (ERAD). These results may drop a hint about the interconnectivity between cross presentation and ER-targeted antigen delivery, provide extra information to the understanding of ERAD-mediated cross priming, and even shed new light on the design and optimization of vaccines against currently intractable cancers or virus-infection.

Dual Inhibition of Endoplasmic Reticulum Stress and Oxidation Stress Manipulates the Polarization of Macrophages under Hypoxia to Sensitize Immunotherapy.

M2-tumor associated macrophages (TAMs) play an important role in tumor genesis, progression, and metastasis, and repolarizing M2-TAMs to immune-promoting M1 type is increasingly recognized as a promising strategy against the clinically intractable carcinomas. It is observed that M2 macrophages have a high tropism to the tumor hypoxic area, with their endoplasmic reticulum (ER) stress-associated IRE1-XBP1 pathway activated to inhibit cell glycolysis, promote oxidative phosphorylation (OXPHOS), and facilitate intracellular lipid accumulation, which in turn shapes the typical phenotypes of M2-TAMs, suggesting that manipulating the ER stress response of M2-TAMs might stand as a breakthrough for antitumor therapy. However, current attempts to repolarize M2 cells remain limited and are greatly challenged by the hypoxic nature of tumors. Also, the high level of reactive oxygen species (ROS) in the tumor microenvironment (TME) is favorable for the polarization of M2-TAMs. Here, we encapsulated KIRA6, an inhibitor of the IRE1-XBP1 pathway, into a reductive nanoemulsion containing α-tocopherol. Our α-T-K had dual inhibitory effects on the ER stress and oxidative stress. Both in vitro and in vivo experiments suggested that α-T-K effectively reprogrammed M2 macrophages even under hypoxia, achieved by increasing glycolysis and suppressing fatty acid oxidation (FAO). In addition, our data revealed that α-T-K not only delayed tumor growth but elevated the curative effect of PD-1 antibody. Our research demonstrated that simultaneous inhibition of ER stress and oxidative stress could effectively repolarize M2-TAMs under hypoxia, which not only filled the current gap in regulating the biological repolarization of macrophages under hypoxia but provided a meaningful reference for the clinical immunotherapy of sensitized anti-PD-1.

Cocktail strategy for 'cold' tumors therapy via active recruitment of CD8+ T cells and enhancing their function.

In immunotherapy, 'cold' tumors, with low T cells infiltration, hardly benefit from the treatment of immune checkpoint inhibitors (ICIs). To address this issue, we screened two 'cold' tumor models for mice with high expression of galectin-3 (Gal-3) and designed a cocktail strategy to actively recruit CD8+ T cells into the tumor microenvironment (TME), which reversed 'cold' tumors into 'hot' and remarkably elevated their ICIs-responsiveness. Gal-3, an important driving force of tumorigenesis, inhibits T cell infiltration into tumor tissue that shapes 'cold' tumor phenotype, and promotes tumor metastasis. In this respect, Gal-3 antagonist G3-C12 peptide was chosen and further loaded into poly(lactic-co-glycolic acid) (PLGA) microspheres, with the prepared G3-C12@PLGA playing a dual role of antitumor, namely, killing two birds with one stone. Specifically, G3-C12@PLGA actively recruit T cells into 'cold' tumors by rescuing IFN-γ, and simultaneously inhibit tumor metastasis induced by Gal-3. Moreover, when combined with chemotherapeutic agent (Oxaliplatin) and anti-PD-1 peptide (APP), the immunopotentiating effect of dendritic cells (DCs) was extremely improved, with T-cell depletion dramatically reversed. In vivo experiments showed that such cocktail therapy exerted remarkable antitumor effect on 'cold' breast cancer (BC) and ovarian serous cancer (OSC). These results indicated that our strategy might be promising in treating 'cold' tumors with high expression of Gal-3, which not only enhance cancer treatment outcome, but provide a new platform for the prevention of postoperative tumor recurrence/metastasis.

Enhanced immune memory through a constant photothermal-metabolism regulation for cancer prevention and treatment.

Tumor vaccine inducing effective and perdurable antitumor immunity has a great potential for cancer prevention and therapy. The key indicator for a successful tumor vaccine is boosting the immune system to produce more memory T cells. Although many tumor vaccines have been designed, few of them involve in actively regulating immune memory CD8+T cells. Here a tumor vaccine vector (TA-Met@MS) by encapsulating tumor antigen (TA), metformin (Met) and Hollow gold nanospheres (HAuNS) into poly (lactic-co-glycolic acid) (PLGA) microspheres was presented. TA via the treatment of photothermal therapy (PTT) showed high immunogenicity and immune-adjuvant effectiveness. And NIR light-mediated photothermal effect can lead to a pulsed-release behavior of TA and Met from the microspheres. The released TA can regulate primary T cell expansion and contraction, and stimulate the production of effector T cells at the early immunization stage. The metabolic behavior of the cells is then intervened from glycolysis into fatty acids oxidation (FAO) through the activation of AMPK mediated by Met, which can enhance T cell survival and facilitate the differentiation of memory CD8+T cells. This study may present a valuable insight to design tumor vaccine for enhanced cancer prevention and therapy.

Appropriate Delivery of the CRISPR/Cas9 System through the Nonlysosomal Route: Application for Therapeutic Gene Editing.

The development of gene delivery has attracted increasing attention, especially when the introduction and application of the CRISPR/Cas9 gene editing system appears promising for gene therapy. However, ensuring biosafety and high gene editing efficiency at the same time poses a great challenge for its in vivo applications. Herein, a pardaxin peptide (PAR)-modified cationic liposome (PAR-Lipo) is developed. The results are indicative that significantly enhanced gene editing efficiency can be obtained through the mediation of PAR-Lipos compared to non-Lipos (non-PAR-modified liposomes) and Lipofectamine 2000, owing to its protection toward carried nucleotide by the prevention of lysosomal capture, prolongation of retention time in cells through the accumulation in the endoplasmic reticulum (ER), and more importantly, facilitation of the nuclear access via an ER-nucleus route. Accumulation of PAR-Lipos in the ER may improve the binding of Cas9 and sgRNA, thus further contributing to the eventually enhanced gene editing efficiency. Given their high biosafety, PAR-Lipos are used to mediate the knockout of the oncogene CDC6 in vivo, which results in significant tumor growth inhibition. This work may provide a useful reference for enhancing the delivery of gene editing systems, thus improving the potential for their future clinical applications.

Targeting DNA to the endoplasmic reticulum efficiently enhances gene delivery and therapy.

Gene therapy mediated by non-viral carriers is gaining an increasing popularity due to its high biosafety and the convenience of production on a large scale, yet inefficient gene delivery is a limiting obstacle. Few gene vectors can avoid the endosome-lysosome route, and as a result, their DNA payloads are easily decomposed during transfection. Herein, a peptide (pardaxin, PAR)-modified cationic liposome (PAR-Lipo) targeting the endoplasmic reticulum (ER) was developed for improving the gene delivery efficiency. Interestingly, compared to non-PAR-modified cationic liposomes (Non-Lipos) and Lipofectamine 2000 (Lipo 2000, a commercial genetic vector), PAR-Lipos showed remarkably higher gene delivery efficiency in vitro and better antitumor efficacy in vivo. It was demonstrated that PAR-Lipos could be accumulated into the ER via a non-lysosome intracellular route after cellular internalization, which induced the retention of the DNA payload in the ER close to the nucleus, while Non-Lipos, like most conventional cationic carriers, mainly presented lysosomal retention after their endocytosis. The unique intracellular transport behavior of PAR-Lipos can enhance the protection of the DNA payload, prolong their residence time in the cell, and promote their entry into the nucleus relying on the intimate relationship between the ER and nuclear membrane, which is the explanation for the enhanced gene-therapy effect mediated by PAR-Lipos. Our research may provide alternative means of efficiently delivering genes in cells.