Enhancement of antitumor effect using dendritic cells activated with natural killer cells in the presence of Toll-like receptor agonist

Dendritic cells (DCs) play a role in natural killer (NK) cell activation, while NK cells are also able to activate and mature DCs. Toll-like receptors (TLRs) on the surface of DCs and NK cells induce the maturation and activation of these cells when engaged with their cognate ligand. We investigated to generate potent DCs by maturation with NK cells in the presence of TLR agonist in vitro and tested the efficacy of these DC vaccinations in mouse colon cancer model. The optimal ratios of DCs versus NK cells were 1:1 to 1:2. Immature DCs were mature with NK cells in the presence of lipopolysaccharide, which is TLR4 agonist, and further addition of IL-2 induced phenotypically and functionally mature bone marrow-derived DCs. These potent DCs exhibited not only high expression of several costimulatory molecules and high production of IL-12p40 and IL-12p70, but also high allogeneic T cells stimulatory capacity, and the induction of the high activities to generate tumor-specific CTLs. Consistently, vaccination with these DCs efficiently inhibited CT-26 tumor growth in mouse colon cancer model when compared to other vaccination strategies. Interestingly, combination therapy of these DC-based vaccines and with low-dose cyclophosphamide showed dramatic inhibition effects of tumor growth. These results suggest that the DCs maturated with NK cells in the presence of TLR agonist are potent inducer of antitumor immune responses in mouse model and may provide a new source of DC-based vaccines for the development of immunotherapy against colon cancer.     

DNA aptamer selected for specific recognition of prostate cancer cells and clinical tissues

Prostate cancer is the most common malignancy in men lack of efficient early diagnosis and therapeutics, calling for effective molecular probes. Herein, we performed cell-based systematic evolution of ligands by exponential enrichment (cell-SELEX) to obtain specific recognition of human prostate cancer cells PC- 3M. Four aptamers were successfully obtained that can bind to target cells with high affinity and specificity. A 51-nt truncated sequence named Xq-2-C1 was identified after further elaborative analysis on the secondary structure. More importantly, the achieved aptamer Xq-2-C1 not only demonstrated excellent specific to target cells, but also revealed specific recognition to clinical prostate cancer tissue. The tissue imaging results showed that Xq-2-C1 had better recognition ratio for clinical prostate cancer tissue samples (85%) compared to the random sequence (9%). These results demonstrate that these newly generated aptamers would furnish potential applications in the early diagnosis and clinical treatment of prostate cancer.     

Diselenide–Pemetrexed Assemblies for Combined Cancer Immuno-, Radio-, and Chemotherapies

Immunotherapy has emerged as a promising new approach for cancer treatment. However, clinically available drugs have been limited until recently, and the antitumor efficacy of most cancer immunotherapies still needs to be improved. Herein, we develop diselenide–pemetrexed assemblies that combine natural killer (NK) cell-based cancer immunotherapy with radiotherapy and chemotherapy in a single system. The assemblies are prepared by co-assembly between pemetrexed and cytosine-containing diselenide through hydrogen bonds. Under γ-radiation, the hydrogen bonds are cleaved, resulting in the release of pemetrexed. At the same time, diselenide can be oxidized to seleninic acid, which suppresses the expression of human leukocyte antigen E (HLA-E) in cancer cells, thus activating the immune response of NK cells. In this way, cancer immunotherapy is combined with radiotherapy and chemotherapy, providing a new strategy for cancer treatment.     

Diselenide–Pemetrexed Assemblies for Combined Cancer Immuno‐, Radio‐, and Chemotherapies

Immunotherapy has emerged as a promising new approach for cancer treatment. However, clinically available drugs have been limited until recently, and the antitumor efficacy of most cancer immunotherapies still needs to be improved. Herein, we develop diselenide–pemetrexed assemblies that combine natural killer (NK) cell‐based cancer immunotherapy with radiotherapy and chemotherapy in a single system. The assemblies are prepared by co‐assembly between pemetrexed and cytosine‐containing diselenide through hydrogen bonds. Under γ‐radiation, the hydrogen bonds are cleaved, resulting in the release of pemetrexed. At the same time, diselenide can be oxidized to seleninic acid, which suppresses the expression of human leukocyte antigen E (HLA‐E) in cancer cells, thus activating the immune response of NK cells. In this way, cancer immunotherapy is combined with radiotherapy and chemotherapy, providing a new strategy for cancer treatment.     

In Situ Synthesis of an Aptamer-Based Polyvalent Antibody Mimic on the Cell Surface for Enhanced Interactions between Immune and Cancer Cells

An ability to promote therapeutic immune cells to recognize cancer cells is important for the success of cell-based cancer immunotherapy. We present a synthetic method for functionalizing the surface of natural killer (NK) cells with a supramolecular aptamer-based polyvalent antibody mimic (PAM). The PAM is synthesized on the cell surface through nucleic acid assembly and hybridization. The data show that PAM has superiority over its monovalent counterpart in powering NKs to bind to cancer cells, and that PAM-engineered NK cells exhibit the capability of killing cancer cells more effectively. Notably, aptamers can, in principle, be discovered against any cell receptors; moreover, the aptamers can be replaced by any other ligands when developing a PAM. Thus, this work has successfully demonstrated a technology platform for promoting interactions between immune and cancer cells.     

In Situ Synthesis of an Aptamer‐Based Polyvalent Antibody Mimic on the Cell Surface for Enhanced Interactions between Immune and Cancer Cells

An ability to promote therapeutic immune cells to recognize cancer cells is important for the success of cell‐based cancer immunotherapy. We present a synthetic method for functionalizing the surface of natural killer (NK) cells with a supramolecular aptamer‐based polyvalent antibody mimic (PAM). The PAM is synthesized on the cell surface through nucleic acid assembly and hybridization. The data show that PAM has superiority over its monovalent counterpart in powering NKs to bind to cancer cells, and that PAM‐engineered NK cells exhibit the capability of killing cancer cells more effectively. Notably, aptamers can, in principle, be discovered against any cell receptors; moreover, the aptamers can be replaced by any other ligands when developing a PAM. Thus, this work has successfully demonstrated a technology platform for promoting interactions between immune and cancer cells.     

Cordycepin Sensitizes Cholangiocarcinoma Cells to Be Killed by Natural Killer-92 (NK-92) Cells

Immunotherapy harnessing immune functions is a promising strategy for cancer treatment. Tumor sensitization is one approach to enhance tumor cell susceptibility to immune cell cytotoxicity that can be used in combination with immunotherapy to achieve therapeutic efficiency. Cordycepin, a bioactive compound that can be extracted from some Cordyceps spp. has been reported to effectively inhibit tumor growth, however, the mechanism of its tumor sensitization activity that enhances immune cell cytotoxicity is unknown. In the present study, we investigated the potency of cordycepin to sensitize a lethal cancer, cholangiocarcinoma (CCA), to natural killer (NK) cells. Treatment with cordycepin prior to and during co-culturing with NK-92 cells significantly increased cell death of KKU-213A as compared to solitary cordycepin or NK treatment. Moreover, sensitization activity was also observed in the combination of NK-92 cells and Cordyceps militaris extract that contained cordycepin as a major component. The cordycepin treatment remarkably caused an increase in TRAIL receptor (DR4 and DR5) expression in KKU-213A, suggesting the possible involvement of TRAIL signaling in KKU-213A sensitization to NK-92 cells. In conclusion, this is the first report on the sensitization activity of cordycepin on CCA cells to NK cytotoxicity, which supports that cordycepin can be further developed as an alternate immunomodulating agent.     

半乳糖保护的Au纳米颗粒的制备及性能研究

通过一种简易的方法,利用D-半乳糖胺和氯金酸制备出了能够用于肝癌细胞靶向识别的Au纳米颗粒探针.该纳米颗粒形貌和尺寸均一并且生物相容性良好.通过改变反应体系的pH能够对Au纳米颗粒的尺寸进行调控.此外,这种新型的纳米颗粒对RCA120还具有超高的检测灵敏度,实验结果显示其检测限度可以达到2μg·L^-1.     

LMP2-specific inhibitors: chemical genetic tools for proteasome biology

The immunoproteasome, having been linked to neurodegenerative diseases and hematological cancers, has been shown to play an important role in MHC class I antigen presentation. However, its other pathophysiological functions are still not very well understood. This can be attributed mainly to a lack of appropriate molecular probes that can selectively modulate the immunoproteasome catalytic subunits. Herein, we report the development of molecular probes that selectively inhibit the major catalytic subunit, LMP2, of the immunoproteasome. We show that these compounds irreversibly modify the LMP2 subunit with high specificity. Importantly, LMP2-rich cancer cells compared to LMP2-deficient cancer cells are more sensitive to growth inhibition by the LMP2-specific inhibitor, implicating an important role of LMP2 in regulating cell growth of malignant tumors that highly express LMP2.     

Efficient amplification of melanoma-specific CD8+ T cells using artificial antigen presenting complex

In vitro large amplification of tumor-specific cytotoxic T lymphocytes (CTLs) and adoptive transfer of these cells is one of the most promising approaches to treat malignant diseases in which an effective immune response is not achieved by active immunization. However, generating sufficient numbers of tumor-specific CTLs stimulated with autologous antigen presenting cells (APCs) in vitro is one of the most problematic steps in the adoptive cell transfer (ACT) therapy. To circumvent this problem, we have developed an artificial antigen presenting complex (aAPCs) using MHC class I molecules loaded with a melanoma-specific TRP-2 peptide epitope. Our results show that TRP-2-specific CD8+ T cells elicited by immunization with recombinant adenovirus expressing the mini-gene epitope are efficiently stimulated and amplified in vitro to a greater extent by aAPCs than by natural splenic APCs. These aAPC-induced CTLs recognized endogenously processed antigens present on B16F10 melanoma cells. Efficient stimulation and proliferation of antigen- specific T cells was also confirmed using ovalbumin peptide-loaded aAPCs and OT-I TCR transgenic cells. These results demonstrate that prior in vivo immunization, which increases the precursor frequency, simplifies posterior expansion of tumor- specific CD8+ T cells, and aAPCs is superior to autologous APC for in vitro amplification. This "prime and expand" regimen can be an alternative method for large amplification of rare tumor-specific CTLs and aAPCs should be a useful tool for ACT immunotherapy.     

In vivo magnetic resonance detection of cancer by using multifunctional magnetic nanocrystals

The unique properties of magnetic nanocrystals provide them with high potential as key probes and vectors in the next generation of biomedical applications. Although superparamagnetic iron oxide nanocrystals have been extensively studied as excellent magnetic resonance imaging (MRI) probes for various cell trafficking, gene expression, and cancer diagnosis, further development of in vivo MRI applications has been very limited. Here, we describe in vivo diagnosis of cancer, utilizing a well-defined magnetic nanocrystal probe system with multiple capabilities, such as small size, strong magnetism, high biocompatibility, and the possession of active functionality for desired receptors. Our magnetic nanocrystals are conjugated to a cancer-targeting antibody, Herceptin, and subsequent utilization of these conjugates as MRI probes has been successfully demonstrated for the monitoring of in vivo selective targeting events of human cancer cells implanted in live mice. Further conjugation of these nanocrystal probes with fluorescent dye-labeled antibodies enables both in vitro and ex vivo optical detection of cancer as well as in vivo MRI, which are potentially applicable for an advanced multimodal detection system. Our study finds that high performance in vivo MR diagnosis of cancer is achievable by utilizing improved and multifunctional material properties of iron oxide nanocrystal probes.     

Fluorescent Probes for Selective Recognition of Hypobromous Acid: Achievements and Future Perspectives

Reactive oxygen species (ROS) have been implicated in numerous pathological processes and their homeostasis facilitates the dynamic balance of intracellular redox states. Among ROS, hypobromous acid (HOBr) has a high similarity to hypochlorous acid (HOCl) in both chemical and physical properties, whereas it has received relatively little attention. Meanwhile, selective recognition of endogenous HOBr suffers great challenges due to the fact that the concentration of this molecule is much lower than that of HOCl. Fluorescence-based detection systems have emerged as very important tools to monitor biomolecules in living cells and organisms owing to distinct advantages, particularly the temporal and spatial sampling for in vivo imaging applications. To date, the development of HOBr-specific fluorescent probes is still proceeding quite slowly, and the research related to this area has not been systematically summarized. In this review, we are the first to review the progress made so far in fluorescent probes for selective recognition and detection of HOBr. The molecular structures, sensing mechanisms, and their successful applications of these probes as bioimaging agents are discussed here in detail. Importantly, we hope this review will call for more attention to this rising field, and that this could stimulate new future achievements.     

葡萄糖酸锌对肿瘤患者淋巴细胞转化率及NK细胞活性的影响

４例肿瘤患者口服葡萄糖酸锌１片（含锌１０ｍｇ）ｔｉｄ×１个月,以淋巴细胞转化率及ＮＫ细胞活性为细胞免疫功能指标,观察了葡萄糖酸锌对免疫功能的影响。结果显示,肿瘤患者口服葡萄糖酸锌后血清锌水平升高（Ｐ＜００５）,ＮＫ细胞活性增强（Ｐ＜００１）、淋巴细胞转化率提高（Ｐ＜００５）。表明对低锌肿瘤患者补锌,对提高细胞免疫功能,改善预后有重要价值     

Tetraphenylethylene Conjugated with a Specific Peptide as a Fluorescence Turn‐On Bioprobe for the Highly Specific Detection and Tracing of Tumor Markers in Live Cancer Cells

Smart molecular probes and flexible methods are attracting remarkable interest for the visualization of cancer‐related biological and chemical events. In this work, a new fluorescence turn‐on probe with dual‐recognition characteristics for the specific imaging of cancer cells is reported. This new bioprobe is rationally designed by linking tetraphenylethylene (TPE), an aggregation‐induced emission (AIE) fluorophore, with the small peptide IHGHHIISVG (referred to as AP2H), a targeting ligand to the broad‐spectrum cancer‐related protein LAPTM4B. The binding of the probe TPE‐AP2H with the target, both in solution and at the cellular level, switches on the fluorescence of TPE because of the inhibition of internal rotations within the TPE framework. Accordingly, this bioprobe allows the real‐time monitoring and subcellular localization of LAPTM4B in cancer cells, with a very high target‐to‐background ratio for the imaging. Furthermore, brighter fluorescence images are detected after incubation of TPE‐AP2H with tumor cells at lower pH values. Thus, this new bioprobe is more advantageous because it can simultaneously target the LAPTM4B protein and sense the characteristic low‐pH environment of tumor cells. In addition, TPE‐AP2H displays high photostability and low cytotoxicity. Therefore, this new bioprobe is promising for the more accurate and reliable imaging of tumor markers in live cancer cells.     

Biomarker-targeted fluorescent probes for breast cancer imaging

This review summarized fluorescent probes for breast cancer imaging according to different biomarkers probes recognized.     

Antitumor Effects of Newcastle Disease Virus Hemagglutinin-neuraminidase Used as a Molecular Adjuvant

Gene therapy is a potentially powerful tool used in cancer therapy. The strength of immune responses induced by some strategies is usually low, therefore, the development of agents capable of enhancing these responses is highlighted. The authors investigated the potential of an approach based on the hemagglutinin-neuraminidase(HN) of Newcastle disease virus(NDV) as a potential immune adjuvant. It was found that recombinant adenovirus(Ad) infected SGC7901 cells expressing HN exhibited both hemagglutinin(HA) and neuraminidase(NA) activities. It was demonstrated that administration of HN induced higher levels of the effector cytokines TNF-α, IFN-α and IFN-γ and increased natural killer(NK) cell activity. Based on the therapeutic tumor model, the results show that the administration of HN with Apoptin led to improved survival and tumor suppression. In conclusion, this study indicates that HN stimulates innate immune responses to make the activity of NK cells increased, which highlights the potential adjuvant activity of HN in cancer gene therapy.     

T Cell Antigen Recognition and Discrimination by Electrochemiluminescence Imaging

Adoptive T lymphocyte (T cell) transfer and tumour-specific peptide vaccines are innovative cancer therapies. An accurate assessment of the specific reactivity of T cell receptors (TCRs) to tumour antigens is required because of the high heterogeneity of tumour cells and the immunosuppressive tumour microenvironment. In this study, we report a label-free electrochemiluminescence (ECL) imaging approach for recognising and discriminating between TCRs and tumour-specific antigens by imaging the immune synapses of T cells. Various T cell stimuli, including agonistic antibodies, auxiliary molecules, and tumour-specific antigens, were modified on the electrode's surface to allow for their interaction with T cells bearing different TCRs. The formation of immune synapses activated by specific stimuli produced a negative (shadow) ECL image, from which T cell antigen recognition and discrimination were evaluated by analysing the spreading area and the recognition intensity of T cells. This approach provides an easy way to assess TCR-antigen specificity and screen both of them for immunotherapies.     

Tuning the Cellular Uptake and Retention of Rhodamine Dyes by Molecular Engineering for High-Contrast Imaging of Cancer Cells

Probes allowing high-contrast discrimination of cancer cells and effective retention are powerful tools for the early diagnosis and treatment of cancer. However, conventional small-molecule probes often show limited performance in both aspects. Herein, we report an ingenious molecular engineering strategy for tuning the cellular uptake and retention of rhodamine dyes. Introduction of polar aminoethyl leads to the increased brightness and reduced cellular uptake of dyes, and this change can be reversed by amino acetylation. Moreover, these modifications allow cancer cells to take up more dyes than normal cells (16-fold) through active transport. Specifically, we further improve the signal contrast (56-fold) between cancer and normal cells by constructing activatable probes and confirm that the released fluorophore can remain in cancer cells with extended time, enabling long-term and specific tumor imaging.     

Charge-tagged ligands: useful tools for immobilising complexes and detecting reaction species during catalysis

In recent years, charge-tagged ligands (CTLs) have become valuable tools in organometallic catalysis. Insertion of an ionic side chain into the molecular skeleton of a known ligand has become a useful protocol for anchoring ligands, and consequently catalysts, in polar and ionic liquid phases. In addition, the insertion of a cationic moiety into a ligand is a powerful tool that can be used to detect reaction intermediates in organometallic catalysis through electrospray ionisation mass spectrometry (ESI-MS) experiments. The insertion of an ionic tag ensures the charge in the intermediates independently of the ESI-MS. For this reason, these ligands have been used as ionic probes in mechanistic studies for several catalytic reactions. Here, we summarise selected examples on the use of CTLs as immobilising agents in organometallic catalysis and as probes for studying mechanisms through ESI-MS.     

Rapid On-Chip Synthesis of Complex Glycomimetics from N-Glycan Scaffolds for Improved Lectin Targeting

C-type lectin receptor (CLR) carbohydrate binding proteins found on immune cells with important functions in pathogen recognition as well as self and non-self-differentiation are increasingly moving into the focus of drug developers as targets for the immune therapy of cancer autoimmune diseases and inflammation and to improve the efficacy of vaccines. The development of molecules with increased affinity and selectivity over the natural glycan binders has largely focused on the synthesis of mono and disaccharide mimetics but glycan array binding experiments have shown increased binding selectivity and affinity for selected larger oligosaccharides that are able to engage in additional favorable interactions beyond the primary binding site. Here, a platform for the rapid preparation and screening of N-glycan mimetics on microarrays is presented that turns a panel of complex glycan core structures into structurally diverse glycomimetics by a combination of enzymatic glycosylation with a nonnatural donor and subsequent cycloaddition with a collection of alkynes. All surface-based reactions were monitored by MALDI-TOF MS to assess conversion and purity of spot compositions. Screening the collection of 374 N-glycomimetics against the plant lectin WFA and the 2 human immune lectins MGL ECD and Langerin ECD produced a number of high affinity binders as lead structures for more selective lectin targeting probes.