Application of PD-1 Blockade in Cancer Immunotherapy

The programmed cell death protein 1 (PD-1) pathway has received considerable attention due to its role in eliciting the immune checkpoint response of T cells, resulting in tumor cells capable of evading immune surveillance and being highly refractory to conventional chemotherapy. Application of anti-PD-1/PD-L1 antibodies as checkpoint inhibitors is rapidly becoming a promising therapeutic approach in treating tumors, and some of them have successfully been commercialized in the past few years. However, not all patients show complete responses and adverse events have been noted, suggesting a better understanding of PD-1 pathway mediated immunosuppression is needed to predict patient response and improve treatment efficacy. Here, we review the progresses on the studies of the mechanistic role of PD-1 pathway in the tumor immune evasion, recent clinical development and commercialization of PD-1 pathway inhibitors, the toxicities associated with PD-1 blockade observed in clinical trials as well as how to improve therapeutic efficacy and safety of cancer immunotherapy.

Chlorin e6 Conjugated Poly(dopamine) Nanospheres as PDT/PTT Dual-Modal Therapeutic Agents for Enhanced Cancer Therapy

Photodynamic therapy (PDT), using a combination of chemical photosensitizers (PS) and light, has been successfully applied as a noninvasive therapeutic procedure to treat tumors by inducing apoptosis or necrosis of cancer cells. However, most current clinically used PS have suffered from the instability in physiological conditions which lead to low photodynamic therapy efficacy. Herein, a highly biocompatible poly(dopamine) (PDA) nanoparticle conjugated with Chlorin e6 (referenced as the PDA-Ce6 nanosphere) was designed as a nanotherapeutic agent to achieve simultaneous photodynamic/photothermal therapy (PDT/PTT). Compared to the free Ce6, the PDA-Ce6 nanosphere exhibited significantly higher PDT efficacy against tumor cells, because of the enhanced cellular uptake and subsequently greater reactive oxygen species (ROS) production upon laser irradiation at 670 nm. Meanwhile, the PDA-Ce6 nanosphere could be also used as a photoabsorbing agent for PTT, because of the excellent photothermal conversion ability of PDA nanoparticle under laser irradiation at 808 nm. Moreover, our prepared nanosphere had extremely low dark toxicity, while excellent phototoxicity under the combination laser irradiation of 670 and 808 nm, both in vitro and in vivo, compared to any single laser irradiation alone. Therefore, our prepared PDA-Ce6 nanosphere could be applied as a very promising dual-modal phototherapeutic agent for enhanced cancer therapy in future clinical applications.

Circular RNAs negatively regulate cancer stem cells by physically binding FMRP against CCAR1 complex in hepatocellular carcinoma

Circular RNA (circRNA) possesses great pre-clinical diagnostic and therapeutic potentials in multiple cancers. It has been reported playing roles in multiple malignant behaviors including proliferation, migration, metastasis and chemoresistance. However, the underlying correlation between circRNAs and cancer stem cells (CSCs) has not been reported yet. Methods: circZKSCAN1 level was detected in HCC tissue microarrays to clarify its prognostic values. Gain and loss function experiments were applied to investigate the role of circZKSCAN1 in HCC stemness. Bioinformatic analysis was used to predict the possible downstream RNA binding protein and further RNA immunoprecipitation sequencing was carried out to identify the RBP-regulated genes. Results: The absence of circZKSCAN1 endowed several malignant properties including cancer stemness and tightly correlated with worse overall and recurrence-free survival rate in HCC. Bioinformatics analysis and RNA immunoprecipitation-sequencing (RIP-seq) results revealed that circZKSCAN1 exerted its inhibitive role by competitively binding FMRP, therefore, block the binding between FMRP and β-catenin-binding protein-cell cycle and apoptosis regulator 1 (CCAR1) mRNA, and subsequently restrain the transcriptional activity of Wnt signaling. In addition, RNA-splicing protein Quaking 5 was found downregulated in HCC tissues and responsible for the reduction of circZKSCAN1. Conclusion: Collectively, this study revealed the mechanisms underlying the regulatory role of circZKSCAN1 in HCC CSCs and identified the newly discovered Qki5-circZKSCAN1-FMRP-CCAR1-Wnt signaling axis as a potentially important therapeutic target for HCC treatment.

Mesenchymal stromal cell therapies: immunomodulatory properties and clinical progress

Mesenchymal stromal cells (MSCs) are a subset of heterogeneous non-hematopoietic fibroblast-like cells that can differentiate into cells of multiple lineages, such as chondrocytes, osteoblasts, adipocytes, myoblasts, and others. These multipotent MSCs can be found in nearly all tissues but mostly located in perivascular niches, playing a significant role in tissue repair and regeneration. Additionally, MSCs interact with immune cells both in innate and adaptive immune systems, modulating immune responses and enabling immunosuppression and tolerance induction. Understanding the biology of MSCs and their roles in clinical treatment is crucial for developing MSC-based cellular therapy for a variety of pathological conditions. Here, we review the progress in the study on the mechanisms underlying the immunomodulatory and regenerative effects of MSCs; update the medical translation of MSCs, focusing on the registration trials leading to regulatory approvals; and discuss how to improve therapeutic efficacy and safety of MSC applications for future.

Glycogen accumulation and phase separation drives liver tumor initiation

Glucose consumption is generally increased in tumor cells to support tumor growth. Interestingly, we report that glycogen accumulation is a key initiating oncogenic event during liver malignant transformation. We found that glucose-6-phosphatase (G6PC) catalyzing the last step of glycogenolysis is frequently downregulated to augment glucose storage in pre-malignant cells. Accumulated glycogen undergoes liquid-liquid phase separation, which results in the assembly of the Laforin-Mst1/2 complex and consequently sequesters Hippo kinases Mst1/2 in glycogen liquid droplets to relieve their inhibition on Yap. Moreover, G6PC or another glycogenolysis enzyme-liver glycogen phosphorylase (PYGL) deficiency in both human and mice results in glycogen storage disease along with liver enlargement and tumorigenesis in a Yap-dependent manner. Consistently, elimination of glycogen accumulation abrogates liver growth and cancer incidence, whereas increasing glycogen storage accelerates tumorigenesis. Thus, we concluded that cancer-initiating cells adapt a glycogen storing mode, which blocks Hippo signaling through glycogen phase separation to augment tumor incidence.

Smartphone-Based Electrochemical Immunoassay for Point-of-Care Detection of SARS-CoV-2 Nucleocapsid Protein

Large-scale, rapid, and inexpensive serological diagnoses of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) are of great interest in reducing virus transmission at the population level; however, their development is greatly plagued by the lack of available point-of-care methods, leading to low detection efficiency. Herein, an ultrasensitive smartphone-based electrochemical immunoassay is reported for rapid (less than 5 min), low-cost, easy-to-implement detection of the SARS-CoV-2 nucleocapsid protein (SARS-CoV-2 N protein). Specifically, the electrochemical immunoassay was fabricated on a screen-printed carbon electrode coated with electrodeposited gold nanoparticles, followed by incubation of anti-N antibody (Ab) and bovine serum albumin as the working electrode. Accompanied by the antigen-antibody reaction between the SARS-CoV-2 N protein and the Ab, the electron transfer between the electroactive species [Fe(CN)6]3-/4- and the electrode surface is disturbed, resulting in reduced square-wave voltammetry currents at 0.075 V versus the Ag/AgCl reference electrode. The proposed immunoassay provided a good linear range with SARS-CoV-2 N protein concentrations within the scope of 0.01-1000 ng/mL (R2 = 0.9992) and the limit of detection down to 2.6 pg/mL. Moreover, the detection data are wirelessly transmitted to the interface of the smartphone, and the corresponding SARS-CoV-2 N protein concentration value is calculated and displayed. Therefore, the proposed portable detection mode offers great potential for self-differential diagnosis of residents, which will greatly facilitate the effective control and large-scale screening of virus transmission in resource-limited areas.

Liposome-Mediated In Situ Formation of Type-I Heterojunction for Amplified Photoelectrochemical Immunoassay

Exploiting innovative sensing mechanisms and their rational implementation for selective and sensitive detection has recently become one of the mainstream research directions of photoelectrochemical (PEC) bioanalysis. In contrast to existing conventional strategies, this study presents a new liposome-mediated method via in situ combining ZnInS nanosheets (ZIS NSs) with SnS2 to form a ZIS NSs/SnS2 type-I heterojunction on fluorine-doped tin oxide (FTO) electrodes for highly sensitive PEC immunoassays. Specifically, alkaline phosphatase (ALP)-encapsulated liposomes were confined within 96-well plates by sandwich immunorecognition and subsequently subjected to lysis treatment. Enzymatically produced H2S by the released ALP was then directed to react with Sn(IV) to engender the ZIS NSs/SnS2 type-I heterojunction on the FTO/ZIS NSs-Sn(IV) electrode, resulting in a change in the photogenerated electron-hole transfer path of the photoelectrode and reduction in current signaling. Exemplified by heart-type fatty acid binding protein (h-FABP) as a target, the constructed PEC sensor showed good stability and selectivity in a biosensing system. Under optimal conditions, the as-prepared sensing platform displayed high sensitivity for h-FABP with a dynamic linear response range of 0.1-1000 pg/mL and a lower detection limit of 55 fg/mL. This research presents the liposome-mediated PEC immunoassay based on in situ type-I heterojunction establishment, providing a new protocol for analyzing various targets of interest.

Exploiting Photoelectric Activities and Piezoelectric Properties of NaNbO3 Semiconductors for Point-of-Care Immunoassay

Point-of-care testing (POCT) technology has made major breakthroughs in community medicine and physician office situations, in tandem with the more ubiquitous and intensive usage of highly integrated quick detection equipment for illness diagnosis, personal care, and mobile healthcare. Although the photoelectrochemical (PEC)-based POCT platform offers the benefits of cheap cost and good user engagement, its commercialization is still limited by the photodetection components' downsizing and mobility, among other factors. In this work, a novel highly integrated PEC biosensor aided by piezophototronics to enhance the efficiency of PEC testing was reported for flexible detection of cancer-associated antigens in biological fluids (prostate-specific antigen, PSA, used as an example). Multiple signal enhancement strategies, including a magnetic bead-linked enzyme-linked immune system catalyzing the production of ascorbic acid from the substrate and a piezoelectric-assisted enhancement strategy, were used for sensitive detection of the analyte to be tested in human body fluids. Unlike the electron transfer mechanism in heterojunctions, piezoelectric semiconductors promote the transfer of electrons and holes by generating piezoelectric potentials in the ultrasonic field, thus contributing to the performance of the PEC testbed. Under optimized conditions, the test platform achieves good correspondence for PSA at 0.02-40 ng mL-1. Impressively, the test devices are comparable to or even superior to gold standard ELISA kits in terms of cost approval and batch testing. This research demonstrates the potential of piezoelectric semiconductors for POC applications in revolutionary PECs and offers innovative thoughts for the development of new PEC bioanalytical components.

Lipid-AuNPs@PDA nanohybrid for MRI/CT imaging and photothermal therapy of hepatocellular carcinoma

Multifunctional theranostic nanoparticles represent an emerging agent with the potential to offer extremely sensitive diagnosis and targeted cancer therapy. Herein, we report the synthesis and characterization of a multifunctional theranostic agent (referred to as LA-LAPNHs) for targeted magnetic resonance imaging/computed X-ray tomography (MRI/CT) dual-mode imaging and photothermal therapy of hepatocellular carcinoma. The LA-LAPNHs were characterized as having a core-shell structure with the gold nanoparticles (AuNPs)@polydopamine (PDA) as the inner core, the indocyanine green (ICG), which is electrostatically absorbed onto the surface of PDA, as the photothermal therapeutic agent, and the lipids modified with gadolinium-1,4,7,10-tetraacetic acid and lactobionic acid (LA), which is self-assembled on the outer surface as the shell. The LA-LAPNHs could be selectively internalized into the hepatocellular cell line (HepG2 cells) but not into HeLa cells due to the specific recognition ability of LA to asialoglycoprotein receptor. Additionally, the dual-mode imaging ability of the LA-LAPNH aqueous solution was confirmed by enhanced MR and CT imaging showing a shorter T1 relaxation time and a higher Hounsfield unit value, respectively. In addition, the LA-LAPNHs showed significant photothermal cytotoxicity against liver cancer cells with near-infrared irradiation due to their strong absorbance in the region between 700 and 850 nm. In summary, this study demonstrates that LA-LAPNHs may be a promising candidate for targeted MR/CT dual-mode imaging and photothermal therapy of hepatocellular carcinoma.

Chemiluminescence-Derived Self-Powered Photoelectrochemical Immunoassay for Detecting a Low-Abundance Disease-Related Protein

Early diagnosis of cancers relies on the sensitive detection of specific biomarkers, but most of the current testing methods are inaccessible to home healthcare due to cumbersome steps, prolonged testing time, and utilization of toxic and hazardous substances. Herein, we developed a portable self-powered photoelectrochemical (PEC) sensing platform for rapid detection of prostate-specific antigen (PSA, as a model disease-related protein) by integrating a self-powered photoelectric signal output system catalyzed with chemiluminescence-functionalized Au nanoparticles (AuNPs) and a phosphomolybdic acid (PMA)-based photochromic visualization platform. TiO2-g-C3N4-PMA photosensitive materials were first synthesized and functionalized on a sensor chip. The sensor consisted of filter paper modified with a photocatalytic material and a regional laser-etched FTO electrode as an alternative to a conventional PEC sensor with a glass-based electrode. The targeting system involved a monoclonal anti-PSA capture antibody-functionalized Fe3O4 magnetic bead (mAb1-MB) and a polyclonal anti-PSA antibody (pAb2)-N-(4-aminobutyl)-N-ethylisoluminol-AuNP (ABEI-AuNP). Based on the signal intensity of the chemiluminescent system, the photochromic device color changed from light yellow to heteropoly blue through the PMA photoelectric materials integrated into the electrode for visualization of the signal output. In addition, the electrical signal in the PEC system was amplified by a sandwich-type capacitor and readout on a handheld digital multimeter. Under optimum conditions, the sensor exhibited high sensitivity relative to PSA in the range of 0.01-50 ng mL-1 with a low detection limit of 6.25 pg mL-1. The flow-through chemiluminescence reactor with a semiautomatic injection device and magnetic separation was avoid of unstable light source intensity inherent in the chemiluminescence process. Therefore, our strategy provides a new horizon for point-of-care analysis and rapid cost-effective clinical diagnosis.

Photodynamic Therapy Combined with Antihypoxic Signaling and CpG Adjuvant as an In Situ Tumor Vaccine Based on Metal-Organic Framework Nanoparticles to Boost Cancer Immunotherapy

Photodynamic therapy (PDT) usually aggravates tumor hypoxia, which promotes the survival and metastasis of residue cancer cells; furthermore, although PDT-induced immunogenic death of cancer cells can induce host antitumor responses, such responses are generally weak and not enough to eliminate the residue cancer cells. Here, metal-organic framework (MOF)-based nanoparticles to combine PDT, antihypoxic signaling, and CpG adjuvant as an in situ tumor vaccine to boost host anticancer responses after PDT are designed. The MOF-based nanoparticles are self-assembled from H2 TCPP and zirconium ions with hypoxia inducible factor (HIF) signaling inhibitor (ACF) and immunologic adjuvant (CpG) loading, and hyaluronic acid (HA) coating on the surface. The final nanoparticles (PCN-ACF-CpG@HA) can specifically target cancer cells overexpressing CD44 receptor though HA; the aggravated hypoxic survival signaling after PDT can be blocked by ACF to inhibit the HIF-1α induced survival and metastasis. With the help of CpG adjuvant, the tumor associated antigens generated from PDT-based cancer cell destruction can initiate strong antitumor immune responses to eliminate residue cancer cells. Taken together, a novel in situ immunostimulatory strategy is designed to synergistically enhance therapeutic effects of PDT by activating host antitumor immune-responses both in vitro and in vivo, which may have great potential for clinical translation in future.

Tumor Microenvironment Responsive Shape-Reversal Self-Targeting Virus-Inspired Nanodrug for Imaging-Guided Near-Infrared-II Photothermal Chemotherapy

Tumor microenvironment responsive multimodal synergistic theranostic strategies can significantly improve the therapeutic efficacy while avoiding severe side effects. Inspired by the fact that special morphology could enhance photothermal conversion efficiency (PCE) and cellular delivery, we developed an acidic tumor microenvironment responsive shape-reversal metal-organic virus-inspired nanodrug for enhancing near-infrared (NIR)-II PCE, increasing cell adhesion, and activating tumor targeting. First, a NIR-I fluorescence probe (IR825), a chemo-drug (pemetrexed, PEM), and a rare-earth metal ion (Nd(III)) were chosen to synthesize a virus-like nanodrug via coordination-driven assembly. Then, the spike-like surface of the nanodrug was further camouflaged by an acidity-sensitive poly(ethylene glycol) "shell" to create virus-core and sphere-shell hierarchical nanoassemblies, which could efficiently prevent immune clearance and prolong systemic circulation. Interestingly, the acidic tumor microenvironment could trigger the shell detachment of nanoassemblies for shape reversal to produce a virus-like surface followed by re-exposure of PEM to synergistically amplify the cellular internalization while enhancing NIR-II PCE. By utilizing the shell-detached virus-like nanodrug core, the tumor microenvironment specific enhanced NIR-II photothermal chemotherapy can be realized under the precise guidance of fluorescence/photoacoustic imaging, thereby achieving complete tumor elimination without recurrence in a single treatment cycle. We envision that integrating the tumor microenvironment responsive ability with  "sphere-to-virus" shape reversal will provide a promising strategy for biomimetic targeted cancer therapy.

Equipping Natural Killer Cells with Specific Targeting and Checkpoint Blocking Aptamers for Enhanced Adoptive Immunotherapy in Solid Tumors

Herein, we propose an aptamer-equipping strategy to generate specific, universal and permeable (SUPER) NK cells for enhanced immunotherapy in solid tumors. NK cells were chemically equipped with TLS11a aptamer targeting HepG2 cells and PDL1-specific aptamer without genetic alteration. The dual aptamer-equipped NK cells exhibited high specificity to tumor cells, resulting in higher cytokine secretion and apoptosis/necrosis compared to parental or single aptamer-equipped NK cells. Interestingly, dual aptamer-equipped NK cells induced remarkable upregulation of PDL1 expression in HepG2 cells, enhancing checkpoint blockade. Furthermore, in vivo intravital imaging demonstrated high infiltration of aptamer-equipped NK cells into deep tumor region, leading to enhanced therapeutic efficacy in solid tumors. This work offers a straightforward chemical strategy to equip NK cells with aptamers, holding considerable potential for enhanced adoptive immunotherapy in solid tumors.

Comprehensive Liquid Profiling of Circulating Tumor DNA and Protein Biomarkers in Long-Term Follow-Up Patients with Hepatocellular Carcinoma

PURPOSE

Circulating tumor DNA (ctDNA) provides a novel approach for detecting tumor burden and predicting clinical outcomes of hepatocellular carcinoma (HCC). Here, we performed a thorough evaluation of HCC circulating genetic features and further fully integrated them to build a robust strategy for HCC monitoring and prognostic outcome assessment.

EXPERIMENTAL DESIGN

We performed target sequencing and low-coverage whole-genome sequencing on plasma samples collected from 34 long-term follow-up patients with HCC to capture tumor somatic SNVs and CNVs, respectively. Clinical information was also obtained to evaluate the prognostic performance of ctDNA comparing with clinically applied protein biomarkers.

RESULTS

All plasma samples before surgery showed somatic genetic variations resembling corresponding tumor tissues. During follow-up, SNVs and CNVs dynamically changed correlating to patients' tumor burden. We integrated the comprehensive ctDNA mutation profiles to provide a robust strategy to accurately assess patients' tumor burden with high consistence comparing with imaging results. This strategy could discover tumor occurrence in advance of imaging for an average of 4.6 months, and showed superior performance than serum biomarkers AFP, AFP-L3%, and Des-Gamma-Carboxy Prothrombin (DCP). Furthermore, our strategy could precisely detect minimal residual disease (MRD) in advance and predict patients' prognostic outcomes for both relapse-free survival (P = 0.001) and overall survival (P = 0.001); further combining ctDNA with DCP could increase the sensitivity for MRD detection.

CONCLUSIONS

We demonstrated that plasma CNV and SNV levels dynamically correlated with patients' tumor burden in HCC. Our strategy of comprehensive mutation profile integration could accurately and better evaluate patients' prognostic risk and detect tumor occurrence in advance than traditional strategies.

Fabrication of Red Blood Cell-Based Multimodal Theranostic Probes for Second Near-Infrared Window Fluorescence Imaging-Guided Tumor Surgery and Photodynamic Therapy

The therapeutic efficacy of fluorescence image-guided tumor surgery and photodynamic therapy (PDT) is impaired by the penetration depth limitation, low signal-to-noise ratio of traditional first near-infrared window (NIR I) fluorescence and the hypoxic tumor microenvironment. Here, a "red blood cell-based multimodal probe" was proposed to achieve enhanced tumor targeting and retention of fluorescent probes after an intravenous injection, so that second near-infrared window (NIR II) fluorescence bioimaging-guided complete tumor resection and high-efficiency photodynamic therapy could then be realized. Methods: The hexanoic acid ester-modified rose bengal (RB-HA), RGD (Arginine-Glycine-Aspartic) peptide and avidin were covalently coupled onto amine-modified upconversion nanoparticles (UCNPs) via EDC/NHS reaction (UCNPs@RB@RGD@avidin). Afterwards, the complex of ICG with bovine serum albumin (BSA) was loaded into RBCs through hypotonic dialysis (RBC@ICG). Then, the membrane proteins of RBC@ICG were biotinylated by biotin-modified phospholipids (RBC@ICG@biotin). Finally, the RBCp (Red Blood Cell based probe) was obtained by crosslinking UCNPs@RB@RGD@avidin to RBC@ICG@biotin through the interaction of avidin and biotin. The obtained multimodal RBCp was extensively characterized, both in vitro and in vivo, including analysis of chemical, physical and fluorescent features, O2 delivery ability, tumor accumulation, NIR II fluorescence bioimaging ability, photodynamic therapeutic efficiency, and biosafety. Results: The RBCp experienced efficient tumor targeting and long tumor retention for almost 4 h after intravenous injection, and the superior signal-to-noise ratio at the optimal time window can be used for guiding precise tumor resection under an 808-nm laser irradiation to facilitate lymph popliteal metastasis surgical delineation. Meanwhile, the RBCp can provide laser-responsive O2 release to enhance the PDT efficiency of popliteal lymph node metastasis under NIR II fluorescence bioimaging guidance. These excellent performances obviously lead to remarkably enhanced synergistic therapeutic effects of tumor surgery and metastatic inhibition. Conclusion: The proposed strategy will develop a new platform to increase surgical resection completeness and improve PDT efficiency, resulting in the successful and complete inhibition of tumor and metastasis, which could offer a promising approach for the clinical translation of malignant tumor treatment.

Platinum Nanozyme-Triggered Pressure-Based Immunoassay Using a Three-Dimensional Polypyrrole Foam-Based Flexible Pressure Sensor

This work describes a novel and portable pressure-based point-of-care (POC) testing strategy for the sensitive and rapid detection of carcinoembryonic antigen (CEA) via a flexible pressure sensor constructed by three-dimensional (3D) polypyrrole (PPy) foam. Initially, platinum nanoparticles (PtNPs) were conjugated to the detection antibodies, which were used to form sandwich-type immunocomplexes with targets and capture antibodies in the reaction cell. Then, the carried PtNPs catalyzed the dissociation of hydrogen peroxide (H2O2) for the generation of oxygen (O2) in a sealed device, translating the biomolecule recognition event into gas pressure. With the increase of pressure, a flexible pressure sensor with 3D polypyrrole foam as the sensing layer was used to sensitively monitor the pressure variations in this system. Thus, the concentration of the target could be quantitatively determined by the pressure response. Under optimal conditions, the pressure-based immunosensor showed good sensing performance for CEA in the dynamic working range from 0.2 to 60 ng/mL with a detection limit of 0.13 ng/mL. The reproducibility, specificity, and accuracy compared with commercial enzyme-linked immunosorbent assay (ELISA) kit were also acceptable. Therefore, this work provides a promising approach for developing portable and sensitive POC testing in the future.

Circular RNA profiling identifies circADAMTS13 as a miR-484 sponge which suppresses cell proliferation in hepatocellular carcinoma

Circular RNA (circRNA) can participate in various biological processes, including tumorigenesis, through their microRNA response elements. Alterations in circRNA profiles during hepatocellular carcinoma (HCC) progression and their clinical significance remain unclear. Here, we present extensive analysis of circRNA profiles in tumor and matched peritumor tissues collected from 10 HCC patients, conducted to identify circRNA related to HCC progression. A total of 42 dysregulated circRNA (38 down-regulated and 4 up-regulated) were identified in HCC tumor tissues compared with matched peritumor tissues, revealing the heterogeneity of circRNA profiles in HCC. CircADAMTS13, derived from Exon 13-14 of the ADAMTS13 gene, was significantly downregulated in HCC tumor tissues. Furthermore, clinicopathological analysis revealed that up-regulation of circADAMTS13 was negatively associated with tumor size but positively associated with prognosis. In addition, overexpression of circADAMTS13 could markedly inhibit HCC cell proliferation in vitro. Bioinformatic analysis and luciferase reporter assays further revealed that circADAMTS13 directly interacts with microRNA (miR)-484. Rescue experiments showed that miR-484 mimics can reverse the tumor-suppressing roles of circADAMTS13 in HCC. Therefore, our results demonstrated that circADAMTS13 can serve as a tumor suppressor during HCC progression via the functional pathway of sponging miR-484.

Nanocluster of superparamagnetic iron oxide nanoparticles coated with poly (dopamine) for magnetic field-targeting, highly sensitive MRI and photothermal cancer therapy

In this paper, a core–shell nanocomposite of clusters of superparamagnetic iron oxide nanoparticles coated with poly(dopamine) (SPION clusters@PDA) is fabricated as a magnetic field-directed theranostic agent that combines the capabilities of highly sensitive magnetic resonance imaging (MRI) and photothermal cancer therapy. The highly concentrated SPION cluster core is suitable for sensitive MRI due to its superparamagnetic properties, and the poly(dopamine) coating layer can induce cancer cell death under near-infrared (NIR) laser irradiation because of the photothermal conversion ability of PDA. MRI scanning reveals that the nanocomposite has relatively high r2 and r2(*) relaxivities, and the r2(*) values are nearly threefold higher than the r2 values because of the clustering of the SPIONs in the nanocomposite core. Due to the rapid response to magnetic field gradients, enhanced cellular uptake of our nanocomposite mediated by an external magnetic field can be achieved, thus producing significantly enhanced local photothermal killing efficiency against cancer cells under NIR irritation.

Tunable Competitive Absorption-Induced Signal-On Photoelectrochemical Immunoassay for Cardiac Troponin I Based on Z-Scheme Metal-Organic Framework Heterojunctions

Recently emerged Z-scheme heterostructure-based immunoassays have presented new opportunities for photoelectrochemical (PEC) biosensing development. Here, we described a tunable signal-on PEC biosensor for the detection of cardiac troponin I (cTnI), which exploited a competitive absorption effect between Cu(II) ions and a Zr metal-organic framework (Zr-MOF) constructed on TiO2 nanorods (Cu2+@Zr-MOF@TiO2 NRs). Water-stable Zr-MOF was coated onto TiO2 NRs on fluorine-doped tin oxide to form a Z-scheme heterostructure substrate (Zr-MOF@TiO2 NRs), which exhibited a high photoelectric response. Cu2+@Zr-MOF@TiO2 NRs, constructed by loading Cu(II) ions onto the architecture of Zr-MOF by electrostatic interaction, demonstrated a low background signal. After sandwich immunorecognition within a 96-well plate, H2S, generated by confined alkaline phosphatase on zeolitic imidazolate framework-8, was directed to react with Cu(II) ions to form CuS. This resulted in an in situ change in the photoelectrode and an enhanced photoelectric signal. The developed PEC biosensing platform exhibited high sensitivity and selectivity for the cTnI immunoassay with a detection limit of 8.6 pg/mL. The Z-scheme-based competition absorption modulation of photoelectrochemistry provides a new strategy for general PEC biosensing development.

Block-Polymer-Restricted Sub-nanometer Pt Nanoclusters Nanozyme-Enhanced Immunoassay for Monitoring of Cardiac Troponin I

Noble-metal nanozymes have demonstrated great potential in various fields. However, aggregation of single-particle nanoparticles severely affects their exposed catalytically active sites to the extent of exhibiting weak enzyme-like activity. Here, we present an organic block surfactant (polyvinylpyrrolidone, PVP) to construct monodisperse water-stable Pt nanoclusters (Pt NCs) for an enhanced immunoassay of cardiac troponin I (cTnI). The PVP-modified Pt NC nanozyme exhibited up to 16.3 U mg-1 peroxidase-mimicking activity, which was mainly attributed to the ligand modification on the surface and the electron-absorbing effect of the ligand on the Pt NCs. The PVP-modified Pt NCs have a lower OH-transition potential, as determined by density functional theory. Under optimized experimental conditions, the enhanced nanozyme immunoassay strategy exhibited an ultrawide dynamic response range of 0.005-50 ng mL-1 for cTnI targets with a detection limit of 1.3 pg mL-1, far superior to some reported test protocols. This work provides a designable pathway for the design of artificial enzymes with high enzyme-like activity to further expand the practical range of enzyme alternatives.

Liposome-Embedded Cu2-xAgxS Nanoparticle-Mediated Photothermal Immunoassay for Daily Monitoring of cTnI Protein Using a Portable Thermal Imager

Functional photothermal nanomaterials have gained widespread attention in the field of precise cancer therapy and early disease diagnosis due to their unique photothermal conversion properties. However, the relatively narrow temperature response range and the outputable accuracy of commercial thermometers limit the accurate detection of biomarkers. Herein, we designed a liposome-embedded Cu2-xAgxS amplification-based photothermal sensor for the accurate determination of cardiac troponin I (cTnI) in health monitoring and point-of-care testing (POCT). The combinable 3D-printing detecting device monitored and visualized target signal changes in the testing system under the excitation of near-infrared (NIR) light, which was recorded and evaluated for possible pathogenicity by a smartphone. Notably, we predicted the potentially efficient thermal conversion efficiency of Cu2-xAgxS from the structure and charge density distribution, calculated by the first-principles and density functional theory (DFT), which provided a theoretical basis for the construction of novel photothermal materials, and the experimental results proved the correctness of the theoretical projections. Under optimal conditions, the photothermal immunoassay showed a dynamic linear range of 0.02-10 ng mL-1 with a detection limit of 11.2 pg mL-1. This work instructively introduces promising theoretical research and provides new insights for the development of sensitive portable photothermal biosensors.

An immune checkpoint score system for prognostic evaluation and adjuvant chemotherapy selection in gastric cancer

Immunosuppressive molecules are extremely valuable prognostic biomarkers across different cancer types. However, the diversity of different immunosuppressive molecules makes it very difficult to accurately predict clinical outcomes based only on a single immunosuppressive molecule. Here, we establish a comprehensive immune scoring system (ISSGC) based on 6 immunosuppressive ligands (NECTIN2, CEACAM1, HMGB1, SIGLEC6, CD44, and CD155) using the LASSO method to improve prognostic accuracy and provide an additional selection strategy for adjuvant chemotherapy of gastric cancer (GC). The results show that ISSGC is an independent prognostic factor and a supplement of TNM stage for GC patients, and it can improve their prognosis prediction accuracy; in addition, it can distinguish GC patients with better prognosis from those with high prognostic nutritional index score; furthermore, ISSGC can also be used as a tool to select GC patients who would benefit from adjuvant chemotherapy independent of their TNM stages, MSI status and EBV status.

Ultrasound-Driven Biomimetic Nanosystem Suppresses Tumor Growth and Metastasis through Sonodynamic Therapy, CO Therapy, and Indoleamine 2,3-Dioxygenase Inhibition

The rational design of nanoplatforms to bypass reticuloendothelial system (RES) clearance, enhance spatiotemporal controllability, and boost host immune responses to achieve synergized tumor-targeted therapeutic purpose is highly desired. Herein, a biomimetic nanosystem is developed for tumor-targeted in situ delivery of singlet oxygen (1O2) and carbon monoxide (CO) in response to exogenous stimulus ultrasound (US) and endogenous stimulus hydrogen peroxide (H2O2) in tumor microenvironment, respectively. Taking advantages of tumor homing and RES evasion abilities of the macrophage membrane coating, our designed nanosystem shows excellent accumulation at the tumor site and effective suppression of tumor growth through US/H2O2-generated 1O2 and CO to induce cell apoptosis and mitochondrial dysfunction. Furthermore, our nanosystem can induce significant tumor immunogenic death by 1O2/CO therapy, then can achieve effective immune responses and long-term immune memory through the combination of indoleamin 2,3-dioxygenase (IDO) signal blocking to effectively against tumor rechallenge and prevent lung metastasis. Taken together, the here-presented therapeutic strategy based on sonodynamic/CO therapy and IDO signaling inhibition might provide a promising perspective for synergistically treating cancer in future clinical translations.

Personalized neoantigen vaccine prevents postoperative recurrence in hepatocellular carcinoma patients with vascular invasion

BACKGROUND

Clinically, prophylactic anti-recurrence treatments for hepatocellular carcinoma (HCC) patients after radical surgery are extremely limited. Neoantigen based vaccine can generate robust anti-tumor immune response in several solid tumors but whether it could induce anti-tumor immune response in HCC and serve as a safe and effective prophylactic strategy for preventing postoperative HCC recurrence still remain largely unclear.

METHODS

Personalized neoantigen vaccine was designed and immunized for 10 HCC patients with high risk of postoperative recurrence in a prime-boost schedule. The safety and immune response were assessed through adverse events, tissue sequencing, ELISpot, TCR sequencing. The clinical response was evaluated by recurrence-free survival (RFS) and personalized circulating tumor DNA (ctDNA) sequencing.

RESULTS

In the 10 enrolled patients, no obvious adverse events were observed during neoantigen vaccinations. Until the deadline of clinical trial, 8 of 10 patients were confirmed with clinical relapse by imaging, the other 2 patients remained relapse-free. From receiving first neoantigen vaccination, the median RFS of 10 patients were 7.4 months. Among 7 patients received all planned neoantigen vaccinations, 5 of them demonstrated neoantigen-induced T cell responses and have significantly longer RFS after radical surgery than other 5 patients without responsive neoantigens or only with prime vaccination and propensity scores matching control patients (p = 0.035). Moreover, tracking personalized neoantigen mutations in ctDNA could provide real-time evaluation of clinical response in HCC patients during neoantigen vaccination and follow up.

CONCLUSION

Personalized neoantigen vaccine is proved as a safe, feasible and effective strategy for HCC anti-recurrence, and its progression could be sensitively monitored by corresponding neoantigen mutations in ctDNA, and thus provided solid information for individualized medicine in HCC.

TRIAL REGISTRATION

This study was registered at Chinese Clinical Trial Registry; Registration number: ChiCTR1900020990 .