Dual cancer stem cell manipulation to enhance phototherapy against tumor progression and metastasis.

Targeting breast cancer stem cells (BCSCs) therapy is a prospective strategy to eliminate tumors owing to the BCSCs-governed drug resistance, tumor progression and metastasis. BCSCs are intrinsically in a disequilibrium state with favorable ability of self-renewal rather than differentiation, resulting in inability of complete tumor eradication. Besides the original BCSCs, epithelial-mesenchymal transition (EMT) process can further facilitate BCSCs regeneration, accompanied by tumor progression and metastasis. Herein, we, for the first time, engineered a photodynamic nanoplatform to manipulate BCSCs against tumor progression and metastasis by not only remolding the disequilibrium state but also blocking the EMT process. The HP@PP was constructed by haloperidol (HP)-incorporated polyethyleneimine-polyhistidine (PP) micelles, which was further integrated with low molecular weight heparin (LMWH)-chlorin e6 (Ce6) conjugate (LC) to form HP@PP/LC nanoparticles (NPs). For HP@PP/LC NPs, the protonation of PP in tumor tissues precisely targeted HP to BCSCs for remolding the disequilibrium state via promoting BCSCs differentiation into tumor cells. Simultaneously, LC conjugate targeted to tumors for exerting EMT blocking ability with LMWH, as well as exerting photodynamic clearance of tumor cells with Ce6 component. Therefore, our nanoplatform provides an emerging strategy for manipulating BCSCs against tumor progression and metastasis, demonstrating a promising photodynamic platform against tumors.

Engineering of a dual-modal phototherapeutic nanoplatform for single NIR laser-triggered tumor therapy.

Theranostic nanoplatforms integrating simultaneously photodynamic therapy (PDT) and photothermal therapy (PTT) exhibit intrinsic advantages in tumor therapy due to distinct mechanisms of action. However, it is challenging to achieve PDT and PTT under single near-infrared (NIR) laser irradiation with a nanoplatform utilizing conventional organic photodynamic agent and inorganic photothermal agent owing to the difference in inherent excitation wavelengths. Particularly, the single NIR light (660 nm)-triggered PTT and PDT nanoplatform, constructed from chlorin e6 (Ce6) and copper sulfide (CuS) nanoparticles (NPs), has never been reported. Herein, we, for the first time, designed and established a dual-modal phototherapeutic nanoplatform that achieved both PTT and PDT under single NIR laser (660 nm) irradiation for Ce6 and CuS NPs with the strategy of core-shell structured CuS@Carbon integrated with Ce6. Introducing of carbon shell not only endows small CuS NPs with excellent tumor accumulation, but also significantly strengthens the photothermal performance of CuS NPs, realizing efficient photothermal performance under 660 nm laser irradiation. Moreover, Ce6 in carbon shell endowed the nanoplatform with photodynamic effect under 660 nm laser irradiation. The as-prepared Ce6/CuS@Carbon nanoplatform thus achieved dual-modal phototherapy under single NIR laser irradiation, significantly inhibiting tumor growth with minimal adverse effects and superior biosafety.

Rational Design of a Robust Antibody-like Small-Molecule Inhibitor Nanoplatform for Enhanced Photoimmunotherapy.

Immune checkpoint blockade of the programmed cell death-ligand 1/programmed cell death-1 (PD-L1/PD-1) pathway via an antibody is a potent strategy for T cell remodeling. Nevertheless, the potency of the antibody is partly compromised by its high price, instability, risk of autoimmune disease, and so forth. Small-molecule inhibitors are interesting alternatives to antibodies. However, tumor-specific delivery of small-molecule inhibitors to the target site for boosting the interruption of the PD-L1/PD-1 pathway is rarely reported. Herein, we designed a tumor-specific delivery nanoplatform that could efficiently deliver the small-molecule inhibitor to the precise target site, greatly enhancing the blocking effect of the PD-L1/PD-1 pathway. Hyaluronic acid (HA) was conjugated with chlorin e6 (Ce6), resulting in a HA-Ce6 conjugate (HC). The nanoplatform was constructed by the HC micelles with the encapsulation of small-molecule inhibitor, BMS 202 (BMS), to form BMS/HC micelles. The target property of HA, combined with the hyaluronidase-induced degradation of HA in the tumor site, enables the as-prepared micelles with tumor-specific delivery of BMS for blocking the PD-L1/PD-1 pathway. With cooperative treatment with the photosensitizer Ce6, the present therapeutic nanoplatform demonstrated excellent photoimmunotherapy for tumor regression in distant tumors and lung metastasis. This strategy of tumor-specific delivery of small-molecule inhibitors provides an effective pathway to strengthen the blocking efficacy of PD-L1/PD-1 on effective photoimmunotherapy.

Task-Specific Design of Immune-Augmented Nanoplatform to Enable High-Efficiency Tumor Immunotherapy.

Potentiating systemic immunity against breast cancer is in the most urgent demand as breast cancer is less sensitive to immune checkpoint blockade. Although phototherapy and some chemotherapy can trigger immunogenic cell death (ICD) for T cell-mediated antitumor immune response, their immunotherapy efficacy is severely restricted by insufficient phototherapeutic capability and severe multidrug resistance (MDR). Inspired by both the hypersensitivity to phototherapy and the key role of MDR for mitochondria, a rationally engineered immunity amplifier via mitochondria-targeted photochemotherapeutic nanoparticles was, for the first time, achieved to fight against low-immunogenic breast cancer without additional immune agents. The newly synthesized task-specific mitochondria-targeted IR780 derivative (T780) was integrated with chemotherapeutic doxorubicin (DOX) to form multifunctional nanoparticles via an assembling strategy along with bovine serum albumin (BSA) as a biomimetic corona (BSA@T780/DOX NPs). The in situ enhancement in both phototherapy and MDR reversal by targeting mitochondria with BSA@T780/DOX NPs boosted highly efficient ICD toward excellent antitumor immune response. The newly developed strategy not only eradicated the primary tumor but also eliminated the bilateral tumors efficiently, as well as preventing metastasis and postsurgical recurrence, demonstrating great interest for fighting against low-immunogenic breast cancer.

Cold to Hot: Rational Design of a Minimalist Multifunctional Photo-immunotherapy Nanoplatform toward Boosting Immunotherapy Capability.

The concept of integrating immunogenic cell death (ICD) with tailoring the immunosuppressive tumor microenvironment (TME) is promising for immunotherapy. Photothermal therapy (PTT) could efficiently induce ICD, while an indoleamine 2,3-dioxygenase (IDO) inhibitor could convert the "cold" TME. Therefore, combination of PTT and the IDO inhibitor is an attractive approach for immunotherapy. Unfortunately, combination of PTT and the IDO inhibitor for tumor therapy is rarely reported. Herein, organic photothermal agent IR820 and IDO inhibitor 1-methyl-tryptophan (1MT) were, for the first time, designed to be an all-rolled-into-one molecule nanoplatform via a molecular engineering strategy. The designed IR820-1MT molecule could self-assemble into nanoparticles with remarkably high dual-therapeutic agent loading (88.8 wt %). Importantly, poor water solubility of 1MT and inadequate targeting and short lifetime of IR820 were all well solved within as-prepared IR820-1MT nanoparticles. The laser-triggered IR820-1MT nanoparticles remarkably enhanced accumulation of cytotoxic T cells, helper T cells, and memory T cells and simultaneously suppressed a proportion of regulatory T cells, resulting in excellent immunotherapy against tumor metastasis and recurrence. Our molecular engineering strategy provides a promising alternative option for design of a robust immunotherapy weapon against tumor metastasis and recurrence.

Tailored graphene oxide-doxorubicin nanovehicles via near-infrared dye-lactobionic acid conjugates for chemo-photothermal therapy.

Graphene oxide (GO), as a drug delivery carrier, has attracted considerable attention because of its interesting properties. However, GO tends to aggregate in aqueous solution. Amphiphilic molecules are usually necessary to stabilize GO. The introduction of these non-functional macromolecules on the one hand reduces drug loading, but on the other hand may cause unpredictable side effects. This study proposes a new strategy for stabilizing GO with a functional photothermal agent, IR820 (new indocyanine green) derivative. IR820 derivative results from the conjugation of active targeted lactobionic acid (LA) with IR820 for the formation of IR820-LA. IR820-LA features central aromatic groups that can associate with the GO basal plane through π-π interactions. The flanking moiety of hydrophilic LA and sulfonic groups thus provides steric stabilization of GO in aqueous solution. Moreover, IR820-LA endows GO/doxorubicin (GO/DOX) nanovehicles with fluorescence imaging ability and actively targeted chemo-photothermal therapy. Experimental results both in vitro and in vivo have indicated its good chemo-photothermal therapeutic effect according to its active tumor targeting ability and pH-sensitive drug release characteristics. Therefore, our GO/DOX/IR820-LA nanohybrids can be excellent nanoplatforms for active tumor-targeted chemo-photothermal therapy with imaging guidance.

A versatile strategy to create an active tumor-targeted chemo-photothermal therapy nanoplatform: A case of an IR-780 derivative co-assembled with camptothecin prodrug.

Self-assembled nanovehicles of chemotherapy drug with photothermal agent are regarded as intriguing chemo-photothermal therapy nanoplatform. However, most of the drugs and photothermal agents have poor water solubility and poor interactions to drive the formation of self-assembled nanovehicles, which is a bottleneck of co-assembled drug/photothermal agent for cancer therapy. Here, we proposed a versatile strategy to create self-assembled chemo-photothermal therapy nanoplatform based on the chemical modification of photothermal agent and drug. The IR-780 and camptothecin (CPT) were chosen as the studied models since they are important photothermal agent and anticancer drug, both of which have such poor water solubility with strong itself molecular interactions that they cannot co-assemble together. IR-780 was modified with an active targeting ligand lactobionic acid (LA) to result in amphiphilic IR780-LA while CPT was modified into redox-sensitive prodrug CPT-ss-CPT through a disulfide linkage to realize its assembly. Well-defined nanoparticles (NPs) could be created through the co-assembling of IR780-LA and CPT-ss-CPT. The IR780-LA/CPT-ss-CPT nanoparticles were demonstrated to be an excellent fluorescence imaging-guided, redox-responsive and enhanced synergistic chemo-photothermal therapy nanoplatform against tumors. Specifically, our chemical modification strategy offers a universal way to create self-assembled chemo-photothermal therapy nanoplatform, which solves the bottleneck of co-assembled drug/photothermal agent for cancer therapy. STATEMENT OF SIGNIFICANCE: Self-assembled nanoparticles of chemotherapeutics with photothermic drugs are regarded as intriguing chemo-photothermal therapy nanoplatform. However, most drugs have too poor solubility and interactions to form into self-assembled nanoparticles. We proposed a versatile strategy to create co-assembled chemo-photothermal therapy nanoparticles based on the chemical modification of common drugs. The IR-780 was modified with an active targeting ligand LA to result in amphiphilic IR780-LA molecules, while CPT was modified into redox-sensitive prodrug CPT-ss-CPT through disulfide linkage. Well-defined IR780-LA/CPT-ss-CPT nanoparticles were created through the co-assembling of IR780-LA and CPT-ss-CPT. The nanoparticles were demonstrated to be an excellent fluorescence imaging-guided, redox-responsive, active targeting chemo-photothermal therapy nanoplatform against tumors. Our strategy offers a versatile way to construct smart chemo-photothermal therapy nanoplatform from common drugs.

Rational Design of IR820- and Ce6-Based Versatile Micelle for Single NIR Laser-Induced Imaging and Dual-Modal Phototherapy.

Phototherapy as a promising cancer diagnostic and therapeutic strategy has aroused extensive attention. However, single-wavelength near-infrared (NIR) light-triggered combinational treatment of photothermal therapy (PTT) and photodynamic therapy (PDT) is still a great challenge. Herein, a multifunctional micelle activated by a single-wavelength laser for simultaneous PTT and PDT as well as fluorescence imaging is developed. Briefly, new indocyanine green (IR820) is conjugated to d-α-tocopheryl polyethylene glycol 1000 succinate (TPGS) via the linker 6-aminocaproic acid, and then, chlorin e6 (Ce6) is encapsulated into the micelles formed by TPGS-IR820 conjugates to fabricate TPGS-IR820/Ce6 micelles. As the well-designed TPGS-IR820 conjugate shares a similar peak absorption wavelength with Ce6, this micelle can be applied with a single NIR laser (660 nm). The stable micelles exhibit excellent photothermal conversion efficiency in vitro and in vivo as well as high singlet oxygen generation capacity in tumor cells. After efficient cellular internalization, the as-prepared micelles display outstanding anticancer activity upon single NIR laser irradiation in vitro and in vivo. Furthermore, TPGS-IR820/Ce6 micelles show negligible systemic toxicity. The highly safe and effective TPGS-IR820/Ce6 micelles can offer an innovative strategy to construct single NIR light-induced PTT and PDT combined phototherapy nanoplatforms via suitable modification of organic phototherapeutic agents.

CuS@MOF-Based Well-Designed Quercetin Delivery System for Chemo-Photothermal Therapy.

Quercetin (QT) is one promising candidate for the treatment of various cancers with virtually no toxic side effects. However, its anticancer effect is severely restricted by its poor bioavailability, low water solubility, and chemical instability in the neutral and alkaline medium. Herein, zeolitic imidazolate framework-8 (ZIF-8) is first reported as the multifunctional nanoplatform to the codelivery of quercetin as an anticancer agent and CuS nanoparticles as a photothermal therapy (PTT) agent for synergistic combination of chemotherapy and PTT as well as overcoming the drawbacks of quercetin. Moreover, folic acid-bovine serum albumin (FA-BSA) conjugates are applied to stabilize the CuS@ZIF-8-QT to promote the bioavailability of quercetin and realize active-targeting drug delivery. Near-infrared (NIR) fluorescent imaging demonstrated the highly increased drug accumulations of FA-BSA/CuS@ZIF-8-QT in tumors, resulting from efficient internalization via FA-receptors-mediated endocytosis. The results of in vivo and in vitro anticancer experiments demonstrate that quercetin and PTT agent can work together efficiently under NIR irradiation, thus remarkably improving the anticancer effect. Therefore, our newly designed FA-BSA/CuS@ZIF-8-QT multifunctional drug delivery system might be a promising nanoplatform for cancer treatment.

pH- and Enzyme-Sensitive IR820-Paclitaxel Conjugate Self-Assembled Nanovehicles for Near-Infrared Fluorescence Imaging-Guided Chemo-Photothermal Therapy.

The short lifetime and easy quick elimination of the near-infrared (NIR) dye new indocyanine green (IR820) in the body restrict its practical application as a photothermal agent in cancer therapy. Meanwhile, the drawback of poor water solubility of the chemotherapeutic drug paclitaxel (PTX) largely restricts its clinical applications. Herein, we, for the first time, combined IR820 and PTX in an "all-in-one" fluorescence imaging-guided chemo-photothermal therapy (PTT) platform by a rational design of a novel pH- and enzyme-sensitive IR820-PTX conjugate assembly. Specifically, the IR820-PTX conjugate nanoparticles exhibit an extremely high therapeutic agent content (IR820 and PTX, 95.7%). Besides the good stability in bloodstream, the IR820-PTX nanoparticles can target tumors for high accumulation via the enhanced permeation and retention effect. Particularly, our IR820-PTX nanoparticles simultaneously solve the obstacles of PTX poor solubility and the short lifetime of IR820 for cancer therapy. The simultaneous release of the free drug and dye can efficiently kill tumor cells by the combination of PTT and chemotherapy via NIR irradiation. Furthermore, the combined therapy can be imaging-guided by measuring the NIR fluorescence imaging resulting from the IR820 component. Therefore, our rationally designed pH- and enzyme-sensitive IR820-PTX conjugate nanoparticles provide an alternative "all-in-one" option for an efficient combinational dual-therapy and imaging.

Preparation of hypocrellin B nanocages in self-assembled apoferritin for enhanced intracellular uptake and photodynamic activity.

Photodynamic therapy (PDT) is a promising modality, which uses light energy to activate a nontoxic photosensitizer to treat various diseases like cancer and infectious diseases. Hypocrellin B (HB) is a naturally occurring photosensitizer isolated from traditional Chinese medicine Hypocrella bambusea. However, the high hydrophobicity and poor selectivity severely limit its application. Apoferritin, a macromolecular protein, can serve as an attractive nanocage to carry HB while improving its water solubility and tumor selectivity. In this study, novel HB-apoferritin nanoparticles (HB-AFT NPs) were successfully developed by assembling HB within the apoferritin nanocage. The self-assembled HB-AFT NPs have a narrow size distribution and smooth surface with an average diameter of 12 nm and a HB encapsulation efficiency of 85%. The morphological observation and circular dichroism analysis showed that the encapsulation strategy of HB did not impair apoferritin structure, and thus it potentially maintained the tumor targeting ability of apoferritin. Compared with free HB solution, HB-AFT NPs exhibited more pronounced photodynamic activity on MDA-MB-231 cells due to the higher intracellular uptake, increased reactive oxygen species (ROS) production and excellent tumor-targeting. All these results suggest that the self-assembled HB-AFT NPs can be considered as a potential photosensitive drug for tumor targeting photodynamic therapy.

Inhibitory effects of S-allylmercaptocysteine against benzo(a)pyrene-induced precancerous carcinogenesis in human lung cells.

The anti-cancer effects of oil-soluble organosulfur compounds in garlic in the initiation phase of carcinogenesis are known. However, there are few experimental studies investigating S-allylmercaptocysteine (SAMC), a water-soluble derivative of garlic. This study investigated whether SAMC prevented the carcinogen benzo(a)pyrene (B(a)P) from inducing precancerous activity in human lung cells (A549 cell line). A549 cells were either pre-treated (PreTM) or concurrently treated (CoTM) with 1µM B(a)P and either 10 or 50 µM SAMC. The 50 µM PreTM group inhibited B(a)P-induced cell proliferation by approximately 100%. The 50 µM SAMC PreTM and CoTM inhibited the B(a)P-induced G2/M phase shift by 100% and 97%, respectively. Furthermore, the PreTM and CoTM groups exhibited the potential to reduce the generation of reactive oxygen species (ROS) relative to the B(a)P group by at least 78%. The SAMC PreTM elevated superoxide dismutase (SOD) by approximately 100%. In this study, we revealed the mechanisms involved in SAMC inhibition of B(a)P-induced carcinogenesis, including suppression of cell proliferation, cell cycle regulation, attenuation of ROS formation, inhibition of DNA damage, increase of SOD activity and inhibition of nuclear factor-kappa B (NF-κB) activity. SAMC appears to be a novel therapeutic candidate for the prevention and treatment of B(a)P-induced human lung cancer.

Allyl methyl disulfide inhibits IL-8 and IP-10 secretion in intestinal epithelial cells via the NF-кB signaling pathway.

Garlic and its active constituents have shown versatile medicinal activities in the prevention and treatment of various disorders. Allyl methyl disulfide (AMDS) was identified as one of the major bioactive components in an effective inhalation fork remedy using fresh garlic paste in our previous study. In this work, we investigated the immunological properties of AMDS to elucidate the underlying mechanisms of the fork inhalation treatment using fresh garlic. The inhibition effect of AMDS on TNF-α-induced IL-8 and IP-10 production in intestinal epithelial cell lines HT-29 and Caco-2 was first evaluated. Pretreatment of the cells with AMDS attenuated IL-8 and IP-10 secretion induced by TNF-α in a dose-dependent manner in the non-cytotoxic concentration range of 20 to 150 µM. Mechanistic studies revealed that AMDS suppressed the accumulation of IL-8 mRNA and inhibited IкBα degradation and NF-кB p65 translocation into the nucleus at both the transcriptional and translational levels, suggesting that the attenuation effort of AMDS on cytokine IL-8 secretion might at least be partially related to the NF-κB signaling pathway. These results suggest that AMDS may be a promising phytochemical agent in the treatment of immunological disorders, such as ulcerative colitis, Crohn's disease, intestinal inflammatory diseases and others. In addition, the mechanistic study data indicated that immune modulation could be one of the therapeutic mechanisms of the effective fork treatment containing AMDS as one of the major components.