Neuropeptidomics of the American Lobster Homarus americanus.

The American lobster, Homarus americanus, is not only of considerable economic importance but has also emerged as a premier model organism in neuroscience research. Neuropeptides, an important class of cell-to-cell signaling molecules, play crucial roles in a wide array of physiological and psychological processes. Leveraging the recently sequenced high-quality draft genome of the American lobster, our study sought to profile the neuropeptidome of this model organism. Employing advanced mass spectrometry techniques, we identified 24 neuropeptide precursors and 101 unique mature neuropeptides in Homarus americanus. Intriguingly, 67 of these neuropeptides were discovered for the first time. Our findings provide a comprehensive overview of the peptidomic attributes of the lobster's nervous system and highlight the tissue-specific distribution of these neuropeptides. Collectively, this research not only enriches our understanding of the neuronal complexities of the American lobster but also lays a foundation for future investigations into the functional roles that these peptides play in crustacean species. The mass spectrometry data have been deposited in the PRIDE repository with the identifier PXD047230.

An Updated Guide to the Identification, Quantitation, and Imaging of the Crustacean Neuropeptidome.

Crustaceans serve as a useful, simplified model for studying peptides and neuromodulation, as they contain numerous neuropeptide homologs to mammals and enable electrophysiological studies at the single-cell and neural circuit levels. Crustaceans contain well-defined neural networks, including the stomatogastric ganglion, oesophageal ganglion, commissural ganglia, and several neuropeptide-rich organs such as the brain, pericardial organs, and sinus glands. As existing mass spectrometry (MS) methods are not readily amenable to neuropeptide studies, there is a great need for optimized sample preparation, data acquisition, and data analysis methods. Herein, we present a general workflow and detailed methods for MS-based neuropeptidomic analysis of crustacean tissue samples and circulating fluids. In conjunction with profiling, quantitation can also be performed with isotopic or isobaric labeling. Information regarding the localization patterns and changes of peptides can be studied via mass spectrometry imaging. Combining these sample preparation strategies and MS analytical techniques allows for a multi-faceted approach to obtaining deep knowledge of crustacean peptidergic signaling pathways.

EndoGenius: Optimized Neuropeptide Identification from Mass Spectrometry Datasets.

Neuropeptides represent a unique class of signaling molecules that have garnered much attention but require special consideration when identifications are gleaned from mass spectra. With highly variable sequence lengths, neuropeptides must be analyzed in their endogenous state. Further, neuropeptides share great homology within families, differing by as little as a single amino acid residue, complicating even routine analyses and necessitating optimized computational strategies for confident and accurate identifications. We present EndoGenius, a database searching strategy designed specifically for elucidating neuropeptide identifications from mass spectra by leveraging optimized peptide-spectrum matching approaches, an expansive motif database, and a novel scoring algorithm to achieve broader representation of the neuropeptidome and minimize reidentification. This work describes an algorithm capable of reporting more neuropeptide identifications at 1% false-discovery rate than alternative software in five Callinectes sapidus neuronal tissue types.

Quantifying the contribution of methane diffusion and ebullition from agricultural ditches.

Agricultural ditches are significant methane (CH4) sources since substantial nutrient inputs stimulate CH4 production and emission. However, few studies have quantified the role of diffusion and ebullition pathways in total CH4 emission from agricultural ditches. This study measured the spatiotemporal variations of diffusive and ebullitive CH4 fluxes from a multi-level ditch system in a typical temperate agriculture area, and assessed their contributions to the total CH4 emission. Results illustrated that the mean annual CH4 flux in the ditch system reached 1475.1 mg m-2 d-1, among which 1376.7 mg m-2 d-1 was emitted via diffusion and 98.5 mg m-2 d-1 via ebullition. Both diffusive and ebullitive fluxes varied significantly across different types of ditches and seasons, with diffusion dominating CH4 emission in middle-size ditches and ebullition dominating in large-size ditches. Diffusion was primarily driven by large nutrient inputs from adjacent farmlands, while hydrological factors like water temperature and depth controlled ebullition. Overall, CH4 emission accounted for 86 % of the global warming potential across the ditch system, with 81 % attributed to diffusion and 5 % to ebullition. This study highlights the importance of agricultural ditches as hotspots for CH4 emissions, particularly the dominant role of the diffusion pathway.

On-Tissue Spatial Proteomics Integrating MALDI-MS Imaging with Shotgun Proteomics Reveals Soy Consumption-Induced Protein Changes in a Fragile X Syndrome Mouse Model.

Fragile X syndrome (FXS), the leading cause of inherited intellectual disability and autism, is caused by the transcriptional silencing of the FMR1 gene, which encodes the fragile X messenger ribonucleoprotein (FMRP). FMRP interacts with numerous brain mRNAs that are involved in synaptic plasticity and implicated in autism spectrum disorders. Our published studies indicate that single-source, soy-based diets are associated with increased seizures and autism. Thus, there is an acute need for an unbiased protein marker identification in FXS in response to soy consumption. Herein, we present a spatial proteomics approach integrating mass spectrometry imaging with label-free proteomics in the FXS mouse model to map the spatial distribution and quantify levels of proteins in the hippocampus and hypothalamus brain regions. In total, 1250 unique peptides were spatially resolved, demonstrating the diverse array of peptidomes present in the tissue slices and the broad coverage of the strategy. A group of proteins that are known to be involved in glycolysis, synaptic transmission, and coexpression network analysis suggest a significant association between soy proteins and metabolic and synaptic processes in the Fmr1KO brain. Ultimately, this spatial proteomics work represents a crucial step toward identifying potential candidate protein markers and novel therapeutic targets for FXS.

Radiofrequency ablation for pediatric recurrent hepatocellular carcinoma: a single-center experience.

PURPOSE: To summarize our single-center experience with percutaneous ultrasound (US)-guided radiofrequency ablation (RFA) for pediatric recurrent hepatocellular carcinoma (RHCC). METHODS: From September 2007 to September 2021, patients under 18 who underwent percutaneous US-guided RFA for RHCC were retrospectively enrolled in this study. Local effectiveness, complications, local tumor progression (LTP), progression free survival (PFS), and overall survival (OS) were evaluated. RESULTS: A total of 10 patients (9 male and 1 female; mean age, 11.7 ± 4 years ; age range, 6-17 years) with 15 intrahepatic RHCC lesions were enrolled in this study. Complete ablation (CA) was achieved in 14 out of 15 lesions (93.3%) after the first RFA. During the follow-up (mean, 63.1 ± 18 months; range, 5.3-123.3 months), LTP did not occur. Five patients died including three with tumor progression and one with liver failure. The accumulative one- and three-year PFS rates were 30% and 10%, respectively. The accumulative one- and three-year OS rates were 77.8% and 44.4%, respectively. CONCLUSIONS: Our single-center experience suggests the safety and feasibility of percutaneous US-guided RFA for pediatric RHCC.

Predictive and prognostic biomarkers of bone metastasis in breast cancer: current status and future directions.

The most common site of metastasis in breast cancer is the bone, where the balance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation is disrupted. This imbalance causes osteolytic bone metastasis in breast cancer, which leads to bone pain, pathological fractures, spinal cord compression, and other skeletal-related events (SREs). These complications reduce patients' quality of life significantly and have a profound impact on prognosis. In this review, we begin by providing a brief overview of the epidemiology of bone metastasis in breast cancer, including current diagnostic tools, treatment approaches, and existing challenges. Then, we will introduce the pathophysiology of breast cancer bone metastasis (BCBM) and the animal models involved in the study of BCBM. We then come to the focus of this paper: a discussion of several biomarkers that have the potential to provide predictive and prognostic value in the context of BCBM-some of which may be particularly compatible with more comprehensive liquid biopsies. Beyond that, we briefly explore the potential of new technologies such as single-cell sequencing and organoid models, which will improve our understanding of tumor heterogeneity and aid in the development of improved biomarkers. The emerging biomarkers discussed hold promise for future clinical application, aiding in the prevention of BCBM, improving the prognosis of patients, and guiding the implementation of personalized medicine.

Incidence and risk factors of lymph node metastasis in breast cancer patients without preoperative chemoradiotherapy and neoadjuvant therapy: analysis of SEER data.

Background: Breast cancer (BC) is the leading cause of death in the female reproductive system, often linked to lymph node involvement, indicating poor prognosis. This study investigated lymph node metastasis incidence and risk factors in M0 stage BC patients who hadn't received preoperative chemoradiotherapy or neoadjuvant therapy. We explored the influence of various factors on lymph node metastasis. Methods: We conducted a retrospective analysis using Surveillance, Epidemiology, and End Results data from BC patients diagnosed between 2010 and 2015. Binary logistic regression and propensity score matching (PSM) assessed significant factors in BC patients without preoperative treatment. We developed predictive nomograms and evaluated model performance using the concordance index, calibration curve, area under the curve, and decision curve analysis. Results: Among 256,504 eligible BC patients, 25.57% had lymph node metastasis. Multivariate logistic regression revealed associations between lymph node metastasis and younger age, African-American ethnicity, central/nipple location, lobular carcinoma, human epidermal growth factor receptor 2 (HER2)-positive status, grade III classification, and T3 stage. PSM confirmed these findings. Interactions were identified between age, race, primary site, histology, breast subtype, grade, and T stage, all influencing lymph node metastasis. Conclusions: This retrospective study identified lymph node metastasis in female BC patients with distinct clinicopathological characteristics who received no preoperative treatment. We constructed valuable nomograms, revealing that: (I) young age (<35 years), African-American race, central/nipple location, infiltrating duct carcinoma, HER2 positivity, high histological grade (grade III), and larger tumor size are risk factors for regional lymph node metastasis; (II) lymph node metastasis may not solely represent the invasive nature of triple-negative BC; (III) patients with different BC subtypes in T1c-T2 stages may benefit from individualized neoadjuvant treatment strategies.

Expression, clinicopathological significance, and prognostic potential of AMPK, p-AMPK, PGC-1α, and TFAM in astrocytomas.

AMP-activated protein kinase (AMPK) is a sensor of energy status that maintains cellular energy homeostasis. Activation of AMPK enhances the expression of proliferator-activated receptor γ coactivator 1α (PGC1-α) and subsequently activates mitochondrial transcription factor A (TFAM) to regulate mitochondrial oxidative respiratory function. The possible functions of AMPK, p-AMPK, PGC-1α, and TFAM and their interactions in astrocytomas are not known. Here, the levels, clinicopathological characteristics, and prognostic potential of AMPK, p-AMPK, PGC-1α, and TFAM expression levels in astrocytomas were evaluated. The results showed that levels of AMPK, p-AMPK, PGC-1α, and TFAM expression was increased in astrocytomas. Strong correlations were observed between AMPK, p-AMPK, PGC-1α, and TFAM expression in patients with astrocytomas. The analysis indicated that the levels of AMPK, p-AMPK, PGC-1α, and TFAM were associated with the survival. AMPK levels, tumor grade, and age were independent prognostic factors predicting poor outcomes in patients with astrocytoma. Together, these results indicate that these 4 targets may play a crucial role in the progression and prognosis of human astrocytomas and that AMPK may represent a potential therapeutic target.

Methods for detecting of cardiac troponin I biomarkers for myocardial infarction using biosensors: a narrative review of recent research.

Background and Objective: In cardiovascular diseases (CVDs), acute myocardial infarction (AMI) is considered one of the leading causes of human death, and its diagnosis mainly relies on the detection of the cardiac biomarker troponin I. Traditional detection methods have certain limitations, which has prompted the development of methods with higher sensitivity and specificity. In recent years, biosensors, as an emerging technology, have been widely applied in the clinical medicine and biodetection fields. We retrieved and reviewed relevant articles published over the past 3 years and subsequently summarized the research progress of different types of biosensors in detecting cardiac troponin I and the challenges faced in achieving simple, specific, and portable point-of-care testing (POCT) technology for bedside rapid detection. The aim of this review is to serve as reference for the early diagnosis and treatment of CVDs. Methods: This study searched for relevant literature published from 2019 to 2022 in the PubMed database of the National Center for Biotechnology Information (NCBI). The keywords used were as follows: "cardiac troponin I", "biosensor", "point-of-care testing", "electrochemical detection", and "surface-enhanced Raman spectroscopy". Key Content and Findings: The review found that biosensor technology has high specificity and sensitivity in the detection of cardiac troponin I and is simpler and more convenient than is traditional laboratory testing. Its vigorous development can facilitate the diagnosis of AMI earlier and faster. Conclusions: This study reviewed the progress of cardiac troponin I detection based on biosensing strategies. We found that cardiac troponin I detection methods based on biosensing strategies have their own advantages and disadvantages in clinical applications, and their sensitivity has been constantly improved. In the future, the detection of cardiac troponin I using biosensing technology will be simpler, faster, more sensitive, and portable.

Development of Potent and Selective Coactivator-Associated Arginine Methyltransferase 1 (CARM1) Degraders.

CARM1 is amplified or overexpressed in many cancer types, and its overexpression correlates with poor prognosis. Potent small-molecule inhibitors for CARM1 have been developed, but the cellular efficacy of the CARM1 inhibitors is limited. We herein report the development of the proteolysis targeting chimera (PROTAC) for CARM1, which contains a CARM1 ligand TP-064, a linker, and a VHL E3 ligase ligand. Compound 3b elicited potent cellular degradation activity (DC50 = 8 nM and Dmax > 95%) in a few hours. Compound 3b degraded CARM1 in VHL- and proteasome-dependent manner and was highly selective for CARM1 over other protein arginine methyltransferases. CARM1 degradation by 3b resulted in potent downregulation of CARM1 substrate methylation and inhibition of cancer cell migration in cell-based assays. Thus, CARM1 PROTACs can be used to interrogate CARM1's cellular functions and potentially be developed as therapeutic agents for targeting CARM1-driven cancers.

Monocular polarized three-dimensional absolute depth reconstruction technology for multi-target scenes.

The traditional polarization three-dimensional (3D) imaging technology has limited applications in the field of vision because it can only obtain the relative depth information of the target. Based on the principle of polarization stereo vision, this study combines camera calibration with a monocular ranging model to achieve high-precision recovery of the target's absolute depth information in multi-target scenes. Meanwhile, an adaptive camera intrinsic matrix prediction method is proposed to overcome changes in the camera intrinsic matrix caused by focusing on fuzzy targets outside the depth of field in multi-target scenes, thereby realizing monocular polarized 3D absolute depth reconstruction under dynamic focusing of targets at different depths. Experimental results indicate that the recovery error of monocular polarized 3D absolute depth information for the clear target is less than 10%, and the detail error is only 0.19 mm. Also, the precision of absolute depth reconstruction remains above 90% after dynamic focusing on the blurred target. The proposed monocular polarized 3D absolute depth reconstruction technology for multi-target scenes can broaden application scenarios of the polarization 3D imaging technology in the field of vision.

Bacillus anthracis spores are internalized in human lung epithelial cells by Rab GTPase-supported macropinocytosis.

Inhalation anthrax, the deadliest form of the disease, requires inhaled B. anthracis spores to escape from the alveolar space and travel to the mediastinal lymph nodes, from where the vegetative form of the pathogen disseminates, resulting in a rapidly fatal outcome. The role of epithelia in alveolar escape is unclear, but previous work suggests these epithelial cells are involved in this process. Using confocal microscopy, we found that B. anthracis spores are internalized more rapidly by A549 type II alveolar epithelial cells compared to hAELVi type I alveolar epithelial cells. Internalization of spores by alveolar epithelial cells requires cytoskeletal rearrangement evidenced by significant inhibition by cytochalasin D, an actin inhibitor. Chemical inhibitors of macropinocytosis significantly downregulated B. anthracis spore internalization in human alveolar cells, while inhibitors of other endocytosis pathways had minimal effects. Additional studies using a macropinosome marker and electron microscopy confirmed the role of macropinocytosis in spore uptake. By colocalization of B. anthracis spores with four endocytic Rab proteins, we demonstrated that Rab31 played a role in B. anthracis spore macropinocytosis. Finally, we confirmed that Rab31 is involved in B. anthracis spore internalization by enhanced spore uptake in Rab31-overexpressing A549 cells. This is the first report that shows B. anthracis spore internalization by macropinocytosis in human epithelial cells. Several Rab GTPases are involved in the process.

RIG-I agonist SLR10 promotes macrophage M1 polarization during influenza virus infection.

Rationale: A family of short synthetic, triphosphorylated stem-loop RNAs (SLRs) have been designed to activate the retinoic-acid-inducible gene I (RIG-I) pathway and induce a potent interferon (IFN) response, which may have therapeutic potential. We investigated immune response modulation by SLR10. We addressed whether RIG-I pathway activation with SLR10 leads to protection of nonsmoking (NS) and cigarette smoke (CS)-exposed mice after influenza A virus (IAV) infection. Methods: Mice were given 25 µg of SLR10 1 day before IAV infection. We compared the survival rates and host immune responses of NS and CS-exposed mice following challenge with IAV. Results: SLR10 significantly decreased weight loss and increased survival rates in both NS and CS-exposed mice during IAV infection. SLR10 administration repaired the impaired proinflammatory response in CS-exposed mice without causing more lung injury in NS mice as assessed by physiologic measurements. Although histopathologic study revealed that SLR10 administration was likely to result in higher pathological scores than untreated groups in both NS and CS mice, this change was not enough to increase lung injury evaluated by lung-to-body weight ratio. Both qRT-PCR on lung tissues and multiplex immunoassay on bronchoalveolar lavage fluids (BALFs) showed that most IFNs and proinflammatory cytokines were expressed at lower levels in SLR10-treated NS mice than control-treaded NS mice at day 5 post infection (p.i.). Remarkably, proinflammatory cytokines IL-6, IL-12, and GM-CSF were increased in CS-exposed mice by SLR10 at day 5 p.i. Significantly, SLR10 elevated the ratio of the two chemokines (CXCL9 and CCL17) in BALFs, suggesting macrophages were polarized to classically activated (M1) status. In vitro testing also found that SLR10 not only stimulated human alveolar macrophage polarization to an M1 phenotype, but also reversed cigarette smoke extract (CSE)-induced M2 to M1 polarization. Conclusions: Our data show that SLR10 administration in mice is protective for both NS and CS-exposed IAV-infected mice. Mechanistically, SLR10 treatment promoted M1 macrophage polarization in the lung during influenza infection. The protective effects by SLR10 may be a promising intervention for therapy for infections with viruses, particularly those with CS-enhanced susceptibility to adverse outcomes.

Global Neuropeptidome Profiling in Response to Predator Stress in Rat: Implications for Post-Traumatic Stress Disorder.

Traumatic stress triggers or exacerbates multiple psychiatric illnesses, including post-traumatic stress disorder (PTSD). Nevertheless, the neurophysiological mechanisms underlying stress-induced pathology remain unclear, in part due to the limited understanding of neuronal signaling molecules, such as neuropeptides, in this process. Here, we developed mass spectrometry (MS)-based qualitative and quantitative analytical strategies to profile neuropeptides in rats exposed to predator odor (an ethologically relevant analogue of trauma-like stress) versus control subjects (no odor) to determine peptidomic alterations induced by trauma. In total, 628 unique neuropeptides were identified across 5 fear-circuitry-related brain regions. Brain-region-specific changes of several neuropeptide families, including granin, ProSAAS, opioids, cholecystokinin, and tachykinin, were also observed in the stressed group. Neuropeptides from the same protein precursor were found to vary across different brain regions, indicating the site-specific effects of predator stress. This study reveals for the first time the interaction between neuropeptides and traumatic stress, providing insights into the molecular mechanisms of stress-induced psychopathology and suggesting putative novel therapeutic strategies for disorders such as PTSD.

Agricultural ditches are hotspots of greenhouse gas emissions controlled by nutrient input.

Agricultural ditches are pervasive in agricultural areas and are potential greenhouse gas (GHG) hotspots, since they directly receive abundant nutrients from neighboring farmlands. However, few studies measure GHG concentrations or fluxes in this particular water course, likely resulting in underestimations of GHG emissions from agricultural regions. Here we conducted a one-year field study to investigate the GHG concentrations and fluxes from typical agricultural ditch systems, which included four different types of ditches in an irrigation district located in the North China Plain. The results showed that almost all the ditches were large GHG sources. The mean fluxes were 333 µmol m-2 h-1 for CH4, 7.1 mmol m-2 h-1 for CO2, and 2.4 µmol m-2 h-1 for N2O, which were approximately 12, 5, and 2 times higher, respectively, than that in the river connecting to the ditch systems. Nutrient input was the primary driver stimulating GHG production and emissions, resulting in GHG concentrations and fluxes increasing from the river to ditches adjacent to farmlands, which potentially received more nutrients. Nevertheless, the ditches directly connected to farmlands showed lower GHG concentrations and fluxes compared to the ditches adjacent to farmlands, possibly due to seasonal dryness and occasional drainage. All the ditches covered approximately 3.3% of the 312 km2 farmland area in the study district, and the total GHG emission from the ditches in this area was estimated to be 26.6 Gg CO2-eq yr-1, with 17.5 Gg CO2, 0.27 Gg CH4, and 0.006 Gg N2O emitted annually. Overall, this study demonstrated that agricultural ditches were hotspots of GHG emissions, and future GHG estimations should incorporate this ubiquitous but underrepresented water course.

Extensive genetic admixture between Tai-Kadai-speaking people and their neighbours in the northeastern region of the Yungui Plateau inferred from genome-wide variations.

BACKGROUND: Yungui Plateau in Southwest China is characterized by multi-language and multi-ethnic communities and is one of the regions with the wealthiest ethnolinguistic, cultural and genetic diversity in East Asia. There are numerous Tai-Kadai (TK)-speaking populations, but their detailed evolutionary history and biological adaptations are still unclear. RESULTS: Here, we genotyped genome-wide SNP data of 77 unrelated TK-speaking Zhuang and Dong individuals from the Yungui Plateau and explored their detailed admixture history and adaptive features using clustering patterns, allele frequency differentiation and sharing haplotype patterns. TK-speaking Zhuang and Dong people in Guizhou are closely related to geographically close TK and Hmong-Mien (HM)-speaking populations. Besides, we identified that Guizhou TK-speaking people have a close genetic relationship with Austronesian (AN)-speaking Atayal and Paiwan people, which is supported by the common origin of the ancient Baiyue tribe. We additionally found subtle genetic differences among the newly studied TK people and previously reported Dais via the fine-scale genetic substructure analysis based on the shared haplotype chunks. Finally, we identified specific selection candidate signatures associated with several essential human immune systems and neurological disorders, which could provide evolutionary evidence for the allele frequency distribution pattern of genetic risk loci. CONCLUSIONS: Our comprehensive genetic characterization of TK people suggested the strong genetic affinity within TK groups and extensive gene flow with geographically close HM and Han people. We also provided genetic evidence that supported the common origin hypothesis of TK and AN people. The best-fitted admixture models further suggested that ancestral sources from northern millet farmers and southern inland and coastal people contributed to the formation of the gene pool of the Zhuang and Dong people.

Source identification in river pollution incidents using a cellular automata model and Bayesian Markov chain Monte Carlo method.

Identification of contaminant sources in rivers is crucial for river protection and emergency response. This study presents an innovative approach for identifying river pollution sources by using Bayesian inference and cellular automata (CA) modeling. A general Bayesian framework is proposed that combines the CA model with observed data to identify unknown sources of river pollution. To reduce the computational burden of the Bayesian inference, a CA contaminant transport model is developed to efficiently simulate pollutant concentration values in the river. These simulated concentration values are then used to calculate the likelihood function of available measurements. The Markov chain Monte Carlo (MCMC) method is used to produce the posterior distribution of contaminant source parameters, which is a sampling-based method that enables the estimation of complex posterior distributions. The suggested methodology is applied to a real case study of the Fen River in Yuncheng City, Shanxi Province, Northern China, and it estimates the release time, release mass, and source location with relative errors below 19%. The research indicates that the proposed methodology is an effective and flexible way to identify the location and concentrations of river contaminant sources.

Peptidomics.

Peptides are biopolymers, typically consisting of 2-50 amino acids. They are biologically produced by the cellular ribosomal machinery or by non-ribosomal enzymes and, sometimes, other dedicated ligases. Peptides are arranged as linear chains or cycles, and include post-translational modifications, unusual amino acids and stabilizing motifs. Their structure and molecular size render them a unique chemical space, between small molecules and larger proteins. Peptides have important physiological functions as intrinsic signalling molecules, such as neuropeptides and peptide hormones, for cellular or interspecies communication, as toxins to catch prey or as defence molecules to fend off enemies and microorganisms. Clinically, they are gaining popularity as biomarkers or innovative therapeutics; to date there are more than 60 peptide drugs approved and more than 150 in clinical development. The emerging field of peptidomics comprises the comprehensive qualitative and quantitative analysis of the suite of peptides in a biological sample (endogenously produced, or exogenously administered as drugs). Peptidomics employs techniques of genomics, modern proteomics, state-of-the-art analytical chemistry and innovative computational biology, with a specialized set of tools. The complex biological matrices and often low abundance of analytes typically examined in peptidomics experiments require optimized sample preparation and isolation, including in silico analysis. This Primer covers the combination of techniques and workflows needed for peptide discovery and characterization and provides an overview of various biological and clinical applications of peptidomics.

Perfluorocarbon nanodrug induced oxygen self-enriching sonodynamic therapy improves cancer immunotherapy after insufficient radiofrequency ablation.

Residual lesions and undetectable metastasis after insufficient radiofrequency ablation (iRFA) are associated with earlier new metastases and poor survival in cancer patients, for induced aggressive tumor phenotype and immunosuppression. Programmed cell death protein 1(PD-1) blockade has been reported to enhance the radiofrequency ablation-elicited antitumor immunity, but its ability to eliminate incompletely ablated residual lesions has been questioned. Here, we report a combined treatment modality post iRFA based on integrating an oxygen self-enriching nanodrug PFH-Ce6 liposome@O2 nanodroplets (PCL@O2)-augmented noninvasive sonodynamic therapy (SDT) with PD-1 blockade. PCL@O2 containing Ce6 as the sonosensitizer and PFH as O2 reservoir, was synthesized as an augmented SDT nanoplatform and showed increased ROS generation to raise effective apoptosis of tumor cells, which also exposed more calreticulin to induce stronger immunogenic cell death (ICD). Combining with PD-1 blockade post iRFA, this optimized SDT induced a better anti-tumor response in MC38 tumor bearing mouse model, which not only arrested residual primary tumor progression, but also inhibited the growth of distant tumor, therefore prolonging the survival. Profiling of immune populations within the tumor draining lymph nodes and tumors further revealed that combination therapy effectively induced ICD, and promoted the maturation of dendritic cells, tumor infiltration of T cells, as well as activation of cytotoxic T lymphocytes. While iRFA alone could result in an increase of regulatory T cells (Tregs) in the residual tumors, SDT plus PD-1 blockade post iRFA reduced the number of Tregs in both primary and distant tumors. Moreover, the combined treatment could significantly initiate long-term immune memory, manifesting as elevated levels of CD8+ and CD4+ central memory cells. Therefore, this study establishes the preclinical proof of concept to apply oxygen self-enriching SDT to augment cancer immunotherapy after iRFA.