Challenges and opportunities in oncology drug development and clinical research in China.

As one of the world's most populous countries, China bears a heavy burden and a broad spectrum of cancers, including unique types, providing a unique environment for drug research and development. In recent years, China has leapt forward in oncology drug development and clinical trials, presenting new opportunities and challenges.

IL-1ß-associated NNT acetylation orchestrates iron-sulfur cluster maintenance and cancer immunotherapy resistance.

Interleukin-1ß (IL-1ß) is a key protein in inflammation and contributes to tumor progression. However, the role of IL-1ß in cancer is ambiguous or even contradictory. Here, we found that upon IL-1ß stimulation, nicotinamide nucleotide transhydrogenase (NNT) in cancer cells is acetylated at lysine (K) 1042 (NNT K1042ac) and thereby induces the mitochondrial translocation of p300/CBP-associated factor (PCAF). This acetylation enhances NNT activity by increasing the binding affinity of NNT for NADP+ and therefore boosts NADPH production, which subsequently sustains sufficient iron-sulfur cluster maintenance and protects tumor cells from ferroptosis. Abrogating NNT K1042ac dramatically attenuates IL-1ß-promoted tumor immune evasion and synergizes with PD-1 blockade. In addition, NNT K1042ac is associated with IL-1ß expression and the prognosis of human gastric cancer. Our findings demonstrate a mechanism of IL-1ß-promoted tumor immune evasion, implicating the therapeutic potential of disrupting the link between IL-1ß and tumor cells by inhibiting NNT acetylation.

Observation of plaid-like spin splitting in a noncoplanar antiferromagnet.

Spatial, momentum and energy separation of electronic spins in condensed-matter systems guides the development of new devices in which spin-polarized current is generated and manipulated1-3. Recent attention on a set of previously overlooked symmetry operations in magnetic materials4 leads to the emergence of a new type of spin splitting, enabling giant and momentum-dependent spin polarization of energy bands on selected antiferromagnets5-10. Despite the ever-growing theoretical predictions, the direct spectroscopic proof of such spin splitting is still lacking. Here we provide solid spectroscopic and computational evidence for the existence of such materials. In the noncoplanar antiferromagnet manganese ditelluride (MnTe2), the in-plane components of spin are found to be antisymmetric about the high-symmetry planes of the Brillouin zone, comprising a plaid-like spin texture in the antiferromagnetic (AFM) ground state. Such an unconventional spin pattern, further found to diminish at the high-temperature paramagnetic state, originates from the intrinsic AFM order instead of spin-orbit coupling (SOC). Our finding demonstrates a new type of quadratic spin texture induced by time-reversal breaking, placing AFM spintronics on a firm basis and paving the way for studying exotic quantum phenomena in related materials.

Anomalous intense coherent secondary photoemission from a perovskite oxide.

Photocathodes-materials that convert photons into electrons through a phenomenon known as the photoelectric effect-are important for many modern technologies that rely on light detection or electron-beam generation1-3. However, current photocathodes are based on conventional metals and semiconductors that were mostly discovered six decades ago with sound theoretical underpinnings4,5. Progress in this field has been limited to refinements in photocathode performance based on sophisticated materials engineering1,6. Here we report unusual photoemission properties of the reconstructed surface of single crystals of the perovskite oxide SrTiO3(100), which were prepared by simple vacuum annealing. These properties are different from the existing theoretical descriptions4,7-10. In contrast to other photocathodes with a positive electron affinity, our SrTiO3 surface produces, at room temperature, discrete secondary photoemission spectra, which are characteristic of efficient photocathode materials with a negative electron affinity11,12. At low temperatures, the photoemission peak intensity is enhanced substantially and the electron beam obtained from non-threshold excitations shows longitudinal and transverse coherence that differs from previous results by at least an order of magnitude6,13,14. The observed emergence of coherence in secondary photoemission points to the development of a previously undescribed underlying process in addition to those of the current theoretical photoemission framework. SrTiO3 is an example of a fundamentally new class of photocathode quantum materials that could be used for applications that require intense coherent electron beams, without the need for monochromatic excitations.

High-throughput functional dissection of noncoding SNPs with biased allelic enhancer activity for insulin resistance-relevant phenotypes.

Most of the single-nucleotide polymorphisms (SNPs) associated with insulin resistance (IR)-relevant phenotypes by genome-wide association studies (GWASs) are located in noncoding regions, complicating their functional interpretation. Here, we utilized an adapted STARR-seq to evaluate the regulatory activities of 5,987 noncoding SNPs associated with IR-relevant phenotypes. We identified 876 SNPs with biased allelic enhancer activity effects (baaSNPs) across 133 loci in three IR-relevant cell lines (HepG2, preadipocyte, and A673), which showed pervasive cell specificity and significant enrichment for cell-specific open chromatin regions or enhancer-indicative markers (H3K4me1, H3K27ac). Further functional characterization suggested several transcription factors (TFs) with preferential allelic binding to baaSNPs. We also incorporated multi-omics data to prioritize 102 candidate regulatory target genes for baaSNPs and revealed prevalent long-range regulatory effects and cell-specific IR-relevant biological functional enrichment on them. Specifically, we experimentally verified the distal regulatory mechanism at IRS1 locus, in which rs952227-A reinforces IRS1 expression by long-range chromatin interaction and preferential binding to the transcription factor HOXC6 to augment the enhancer activity. Finally, based on our STARR-seq screening data, we predicted the enhancer activity of 227,343 noncoding SNPs associated with IR-relevant phenotypes (fasting insulin adjusted for BMI, HDL cholesterol, and triglycerides) from the largest available GWAS summary statistics. We further provided an open resource (http://www.bigc.online/fnSNP-IR) for better understanding genetic regulatory mechanisms of IR-relevant phenotypes.

LncRNA CamK-A Regulates Ca2+-Signaling-Mediated Tumor Microenvironment Remodeling.

Cancer cells entail metabolic adaptation and microenvironmental remodeling to survive and progress. Both calcium (Ca2+) flux and Ca2+-dependent signaling play a crucial role in this process, although the underlying mechanism has yet to be elucidated. Through RNA screening, we identified one long noncoding RNA (lncRNA) named CamK-A (lncRNA for calcium-dependent kinase activation) in tumorigenesis. CamK-A is highly expressed in multiple human cancers and involved in cancer microenvironment remodeling via activation of Ca2+-triggered signaling. Mechanistically, CamK-A activates Ca2+/calmodulin-dependent kinase PNCK, which in turn phosphorylates IκBα and triggers calcium-dependent nuclear factor κB (NF-κB) activation. This regulation results in the tumor microenvironment remodeling, including macrophage recruitment, angiogenesis, and tumor progression. Notably, our human-patient-derived xenograft (PDX) model studies demonstrate that targeting CamK-A robustly impaired cancer development. Clinically, CamK-A expression coordinates with the activation of CaMK-NF-κB axis, and its high expression indicates poor patient survival rate, suggesting its role as a potential biomarker and therapeutic target.

Enzyme-catalysed [6+4] cycloadditions in the biosynthesis of natural products.

Pericyclic reactions are powerful transformations for the construction of carbon-carbon and carbon-heteroatom bonds in organic synthesis. Their role in biosynthesis is increasingly apparent, and mechanisms by which pericyclases can catalyse reactions are of major interest1. [4+2] cycloadditions (Diels-Alder reactions) have been widely used in organic synthesis2 for the formation of six-membered rings and are now well-established in biosynthesis3-6. [6+4] and other 'higher-order' cycloadditions were predicted7 in 1965, and are now increasingly common in the laboratory despite challenges arising from the generation of a highly strained ten-membered ring system8,9. However, although enzyme-catalysed [6+4] cycloadditions have been proposed10-12, they have not been proven to occur. Here we demonstrate a group of enzymes that catalyse a pericyclic [6+4] cycloaddition, which is a crucial step in the biosynthesis of streptoseomycin-type natural products. This type of pericyclase catalyses [6+4] and [4+2] cycloadditions through a single ambimodal transition state, which is consistent with previous proposals11,12. The [6+4] product is transformed to a less stable [4+2] adduct via a facile Cope rearrangement, and the [4+2] adduct is converted into the natural product enzymatically. Crystal structures of three pericyclases, computational simulations of potential energies and molecular dynamics, and site-directed mutagenesis establish the mechanism of this transformation. This work shows how enzymes are able to catalyse concerted pericyclic reactions involving ambimodal transition states.

qPTM: an updated database for PTM dynamics in human, mouse, rat and yeast.

Post-translational modifications (PTMs) are critical molecular mechanisms that regulate protein functions temporally and spatially in various organisms. Since most PTMs are dynamically regulated, quantifying PTM events under different states is crucial for understanding biological processes and diseases. With the rapid development of high-throughput proteomics technologies, massive quantitative PTM proteome datasets have been generated. Thus, a comprehensive one-stop data resource for surfing big data will benefit the community. Here, we updated our previous phosphorylation dynamics database qPhos to the qPTM (http://qptm.omicsbio.info). In qPTM, 11 482 553 quantification events among six types of PTMs, including phosphorylation, acetylation, glycosylation, methylation, SUMOylation and ubiquitylation in four different organisms were collected and integrated, and the matched proteome datasets were included if available. The raw mass spectrometry based false discovery rate control and the recurrences of identifications among datasets were integrated into a scoring system to assess the reliability of the PTM sites. Browse and search functions were improved to facilitate users in swiftly and accurately acquiring specific information. The results page was revised with more abundant annotations, and time-course dynamics data were visualized in trend lines. We expected the qPTM database to be a much more powerful and comprehensive data repository for the PTM research community.

Multiplex assays reveal anti-EBV antibody profile and its implication in detection and diagnosis of nasopharyngeal carcinoma.

Epstein-Barr virus (EBV) is detected in nearly 100% of nonkeratinizing nasopharyngeal carcinoma (NPC) and EBV-based biomarkers are used for NPC screening in endemic regions. Immunoglobulin A (IgA) against EBV nuclear antigen 1 (EBNA1) and viral capsid antigen (VCA), and recently identified anti-BNLF2b antibodies have been shown to be the most effective screening tool; however, the screening efficacy still needs to be improved. This study developed a multiplex serological assay by testing IgA and immunoglobulin G (IgG) antibodies against representative EBV antigens that are highly transcribed in NPC and/or function crucially in viral reactivation, including BALFs, BNLF2a/b, LF1, LF2, and Zta (BZLF1). Among them, BNLF2b-IgG had the best performance distinguishing NPC patients from controls (area under the curve: 0.951, 95% confidence interval [CI]: 0.913-0.990). Antibodies to lytic antigens BALF2 and VCA were significantly higher in advanced-stage than in early-stage tumors; in contrast, antibodies to latent protein EBNA1 and early lytic antigen BNLF2b were not correlated with tumor progression. Accordingly, a novel strategy combining EBNA1-IgA and BNLF2b-IgG was proposed and validated improving the integrated discrimination by 15.8% (95% CI: 9.8%-21.7%, p < .0001) compared with the two-antibody method. Furthermore, we found EBV antibody profile in patients was more complicated compared with that in healthy carriers, in which stronger correlations between antibodies against different phases of antigens were observed. Overall, our serological assay indicated that aberrant latent infection of EBV in nasopharyngeal epithelial cells was probably a key step in NPC initiation, while more lytic protein expression might be involved in NPC progression.

Cetuximab plus FOLFOXIRI versus cetuximab plus FOLFOX as conversion regimen in RAS/BRAF wild-type patients with initially unresectable colorectal liver metastases (TRICE trial): A randomized controlled trial.

BACKGROUND: It remains unclear whether intensification of the chemotherapy backbone in tandem with an anti-EGFR can confer superior clinical outcomes in a cohort of RAS/BRAF wild-type colorectal cancer (CRC) patients with initially unresectable colorectal liver metastases (CRLM). To that end, we sought to comparatively evaluate the efficacy and safety of cetuximab plus FOLFOXIRI (triplet arm) versus cetuximab plus FOLFOX (doublet arm) as a conversion regimen (i.e., unresectable to resectable) in CRC patients with unresectable CRLM. METHODS AND FINDINGS: This open-label, randomized clinical trial was conducted from April 2018 to December 2022 in 7 medical centers across China, enrolling 146 RAS/BRAF wild-type CRC patients with initially unresectable CRLM. A stratified blocked randomization method was utilized to assign patients (1:1) to either the cetuximab plus FOLFOXIRI (n = 72) or cetuximab plus FOLFOX (n = 74) treatment arms. Stratification factors were tumor location (left versus right) and resectability (technically unresectable versus ≥5 metastases). The primary outcome was the objective response rate (ORR). Secondary outcomes included the median depth of tumor response (DpR), early tumor shrinkage (ETS), R0 resection rate, progression-free survival (PFS), overall survival (not mature at the time of analysis), and safety profile. Radiological tumor evaluations were conducted by radiologists blinded to the group allocation. Primary efficacy analyses were conducted based on the intention-to-treat population, while safety analyses were performed on patients who received at least 1 line of chemotherapy. A total of 14 patients (9.6%) were lost to follow-up (9 in the doublet arm and 5 in the triplet arm). The ORR was comparable following adjustment for stratification factors, with 84.7% versus 79.7% in the triplet and doublet arms, respectively (odds ratio [OR] 0.70; 95% confidence intervals [CI] [0.30, 1.67], Chi-square p = 0.42). Moreover, the ETS rate showed no significant difference between the triplet and doublet arms (80.6% (58/72) versus 77.0% (57/74), OR 0.82, 95% CI [0.37, 1.83], Chi-square p = 0.63). Although median DpR was higher in the triplet therapy group (59.6%, interquartile range [IQR], [50.0, 69.7] versus 55.0%, IQR [42.8, 63.8], Mann-Whitney p = 0.039), the R0/R1 resection rate with or without radiofrequency ablation/stereotactic body radiation therapy was comparable with 54.2% (39/72) of patients in the triplet arm versus 52.7% (39/74) in the doublet arm. At a median follow-up of 26.2 months (IQR [12.8, 40.5]), the median PFS was 11.8 months in the triplet arm versus 13.4 months in the doublet arm (hazard ratio [HR] 0.74, 95% CI [0.50, 1.11], Log-rank p = 0.14). Grade ≥ 3 events were reported in 47.2% (35/74) of patients in the doublet arm and 55.9% (38/68) of patients in the triplet arm. The triplet arm was associated with a higher incidence of grade ≥ 3 neutropenia (44.1% versus 27.0%, p = 0.03) and diarrhea (5.9% versus 0%, p = 0.03). The primary limitations of the study encompass the inherent bias in subjective surgical decisions regarding resection feasibility, as well as the lack of a centralized assessment for ORR and resection. CONCLUSIONS: The combination of cetuximab with FOLFOXIRI did not significantly improve ORR compared to cetuximab plus FOLFOX. Despite achieving an enhanced DpR, this improvement did not translate into improved R0 resection rates or PFS. Moreover, the triplet arm was associated with an increase in treatment-related toxicity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03493048.

Zolbetuximab plus mFOLFOX6 in patients with CLDN18.2-positive, HER2-negative, untreated, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma (SPOTLIGHT): a multicentre, randomised, double-blind, phase 3 trial.

BACKGROUND: Zolbetuximab, a monoclonal antibody targeting claudin-18 isoform 2 (CLDN18.2), has shown efficacy in patients with CLDN18.2-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma. We report the results of the SPOTLIGHT trial, which investigated the efficacy and safety of first-line zolbetuximab plus mFOLFOX6 (modified folinic acid [or levofolinate], fluorouracil, and oxaliplatin regimen) versus placebo plus mFOLFOX6 in patients with CLDN18.2-positive, HER2-negative, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma. METHODS: SPOTLIGHT is a global, randomised, placebo-controlled, double-blind, phase 3 trial that enrolled patients from 215 centres in 20 countries. Eligible patients were aged 18 years or older with CLDN18.2-positive (defined as ≥75% of tumour cells showing moderate-to-strong membranous CLDN18 staining), HER2-negative (based on local or central evaluation), previously untreated, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma, with radiologically evaluable disease (measurable or non-measurable) according to Response Evaluation Criteria in Solid Tumors version 1.1; an Eastern Cooperative Oncology Group performance status score of 0 or 1; and adequate organ function. Patients were randomly assigned (1:1) via interactive response technology and stratified according to region, number of organs with metastases, and previous gastrectomy. Patients received zolbetuximab (800 mg/m2 loading dose followed by 600 mg/m2 every 3 weeks) plus mFOLFOX6 (every 2 weeks) or placebo plus mFOLFOX6. The primary endpoint was progression-free survival assessed by independent review committee in all randomly assigned patients. Safety was assessed in all treated patients. The study is registered with ClinicalTrials.gov, NCT03504397, and is closed to new participants. FINDINGS: Between June 21, 2018, and April 1, 2022, 565 patients were randomly assigned to receive either zolbetuximab plus mFOLFOX6 (283 patients; the zolbetuximab group) or placebo plus mFOLFOX6 (282 patients; the placebo group). At least one dose of treatment was administered to 279 (99%) of 283 patients in the zolbetuximab group and 278 (99%) of 282 patients in the placebo group. In the zolbetuximab group, 176 (62%) patients were male and 107 (38%) were female. In the placebo group, 175 (62%) patients were male and 107 (38%) were female. The median follow-up duration for progression-free survival was 12·94 months in the zolbetuximab group versus 12·65 months in the placebo group. Zolbetuximab treatment showed a significant reduction in the risk of disease progression or death compared with placebo (hazard ratio [HR] 0·75, 95% CI 0·60-0·94; p=0·0066). The median progression-free survival was 10·61 months (95% CI 8·90-12·48) in the zolbetuximab group versus 8·67 months (8·21-10·28) in the placebo group. Zolbetuximab treatment also showed a significant reduction in the risk of death versus placebo (HR 0·75, 95% CI 0·60-0·94; p=0·0053). Treatment-emergent grade 3 or worse adverse events occurred in 242 (87%) of 279 patients in the zolbetuximab group versus 216 (78%) of 278 patients in the placebo group. The most common grade 3 or worse adverse events were nausea, vomiting, and decreased appetite. Treatment-related deaths occurred in five (2%) patients in the zolbetuximab group versus four (1%) patients in the placebo group. No new safety signals were identified. INTERPRETATION: Targeting CLDN18.2 with zolbetuximab significantly prolonged progression-free survival and overall survival when combined with mFOLFOX6 versus placebo plus mFOLFOX6 in patients with CLDN18.2-positive, HER2-negative, locally advanced unresectable or metastatic gastric or gastro-oesophageal junction adenocarcinoma. Zolbetuximab plus mFOLFOX6 might represent a new first-line treatment in these patients. FUNDING: Astellas Pharma, Inc.

Aberrant accumulation of ceramides in mitochondria triggers cell death by inducing autophagy in Arabidopsis.

Sphingolipids are membrane lipids and play critical roles in signal transduction. Ceramides are central components of sphingolipid metabolism that are involved in cell death. However, the mechanism of ceramides regulating cell death in plants remains unclear. Here, we found that ceramides accumulated in mitochondria of accelerated cell death 5 mutant (acd5), and expression of mitochondrion-localized ceramide kinase (ACD5) suppressed mitochondrial ceramide accumulation and the acd5 cell death phenotype. Using immuno-electron microscopy, we observed hyperaccumulation of ceramides in acer acd5 double mutants, which are characterized by mutations in both ACER (alkaline ceramidase) and ACD5 genes. The results confirmed that plants with specific ceramide accumulation exhibited localization of ceramides to mitochondria, resulting in an increase in mitochondrial reactive oxygen species production. Interestingly, when compared with the wild type, autophagy-deficient mutants showed stronger resistance to ceramide-induced cell death. Lipid profiling analysis demonstrated that plants with ceramide accumulation exhibited a significant increase in phosphatidylethanolamine levels. Furthermore, exogenous ceramide treatment or endogenous ceramide accumulation induces autophagy. When exposed to exogenous ceramides, an increase in the level of the autophagy-specific ubiquitin-like protein, ATG8e, associated with mitochondria, where it directly bound to ceramides. Taken together, we propose that the accumulation of ceramides in mitochondria can induce cell death by regulating autophagy.

Global prevalence of claudin 18 isoform 2 in tumors of patients with locally advanced unresectable or metastatic gastric or gastroesophageal junction adenocarcinoma.

BACKGROUND: Limited data exist for global prevalence of claudin 18 isoform 2 (CLDN18.2) positivity and association of CLDN18.2 status with clinical and tumor characteristics in patients with locally advanced (LA) unresectable or metastatic gastric or gastroesophageal junction (mG/GEJ) adenocarcinoma. We report prevalence of CLDN18.2 positivity (phase 3; SPOTLIGHT, NCT03504397; GLOW, NCT03653507) and concordance of CLDN18.2 status between a subset of pair-matched tumor samples (phase 2, ILUSTRO, NCT03505320; phase 1, NCT03528629) from clinical studies of zolbetuximab. METHODS: Tumor samples from patients with LA unresectable or mG/GEJ adenocarcinoma were tested for CLDN18.2 status by immunohistochemistry. Human epidermal growth factor receptor 2 (HER2) expression was tested per central or local assessment. RESULTS: Across SPOTLIGHT and GLOW, the prevalence of CLDN18.2 positivity (≥ 75% of tumor cells demonstrating moderate-to-strong membranous CLDN18 staining) was 38.4%. Prevalence was similar in gastric versus GEJ adenocarcinoma samples and regardless of collection method (biopsy versus resection) or collection site (primary versus metastatic). CLDN18.2 positivity was most prevalent in patients with diffuse-type tumors. In ILUSTRO and the phase 1 study, concordance of CLDN18.2 positivity was 61.1% between archival (i.e., any time before treatment) and baseline (i.e., ≤ 3 months before first treatment) samples, and concordance of any CLDN18 staining (≥ 1% of tumor cells demonstrating moderate-to-strong membranous CLDN18 staining) was 88.9%. CONCLUSIONS: CLDN18.2 was a highly prevalent biomarker in patients with HER2-negative, LA unresectable or mG/GEJ adenocarcinoma. CLDN18.2 positivity remained relatively stable over time in many patients. Biomarker testing for CLDN18.2 should be considered in standard clinical practice in these patients.

Zolbetuximab plus chemotherapy for locally advanced unresectable or metastatic stomach or gastroesophageal junction cancers: a plain language summary.

WHAT IS THIS SUMMARY ABOUT?: This is a summary of two articles. The first article is about a clinical trial called SPOTLIGHT and it was published in the medical journal The Lancet in in April of 2023. The second article is about a clinical trial called GLOW and it was published in the medical journal Nature Medicine in July of 2023. WHAT ARE THE KEY TAKEAWAYS?: Until recently, chemotherapy was the first treatment given to people with stomach cancer or gastroesophageal junction (or GEJ) cancer that is locally advanced unresectable or metastatic. When cancer cells have high amounts of the protein CLDN18.2 but do not have high amounts of the protein HER2, the cancer is known as CLDN18.2-positive (or CLDN18.2+) and HER2-negative (or HER2-). New medicines to treat cancer are being developed. These medicines attach to proteins on cancer cells to help the body recognize and kill cancer cells.The clinical trials SPOTLIGHT and GLOW included participants with CLDN18.2+ and HER2- stomach or GEJ cancer that was locally advanced unresectable or metastatic. These trials looked at whether adding a medicine called zolbetuximab to chemotherapy as the first treatment for cancer helped people live longer before their tumors grew bigger or new tumors grew, after starting the trial. These studies also looked at whether adding zolbetuximab to chemotherapy helped people live longer after starting the trial. WHAT WERE THE MAIN CONCLUSIONS REPORTED BY THE RESEARCHERS?: In SPOTLIGHT and GLOW, on average, participants assigned to zolbetuximab plus chemotherapy lived 1.4 to 1.9 months longer before their tumors grew bigger or new tumors grew, after starting the trial, than participants assigned to a placebo plus chemotherapy. On average, participants assigned to zolbetuximab plus chemotherapy also lived 2.2 to 2.7 months longer, after starting the trial, than participants assigned to a placebo plus chemotherapy. These results suggest that zolbetuximab plus chemotherapy could be a new first treatment for people with CLDN18.2+ and HER2- stomach or GEJ cancer that is locally advanced unresectable or metastatic.Clinical Trial Registration: NCT03504397 (SPOTLIGHT); NCT03653507 (GLOW).

The clinical trials SPOTLIGHT and GLOW showed that, on average, participants with stomach or GEJ cancer assigned to zolbetuximab plus chemotherapy lived 2.2 to 2.7 months longer than participants assigned to a placebo plus chemotherapy.

Naringin attenuates Actinobacillus pleuropneumoniae-induced acute lung injury via MAPK/NF-κB and Keap1/Nrf2/HO-1 pathway.

Actinobacillus pleuropneumoniae (APP) causes porcine pleuropneumonia (PCP), which is clinically characterized by acute hemorrhagic, necrotizing pneumonia, and chronic fibrinous pneumonia. Although many measures have been taken to prevent the disease, prevention and control of the disease are becoming increasingly difficult due to the abundance of APP sera, weak vaccine cross-protection, and increasing antibiotic resistance in APP. Therefore, there is an urgent need to develop novel drugs against APP infection to prevent the spread of APP. Naringin (NAR) has been reported to have an excellent therapeutic effect on pulmonary diseases, but its therapeutic effect on lung injury caused by APP is not apparent. Our research has shown that NAR was able to alleviate APP-induced weight loss and quantity of food taken and reduce the number of WBCs and NEs in peripheral blood in mice; pathological tissue sections showed that NAR was able to prevent and control APP-induced pathological lung injury effectively; based on the establishment of an in vivo/in vitro model of APP inflammation, it was found that NAR was able to play an anti-inflammatory role through inhibiting the MAPK/NF-κB signaling pathway and exerting anti-inflammatory effects; additionally, NAR activating the Nrf2 signalling pathway, increasing the secretion of antioxidant enzymes Nqo1, CAT, and SOD1, inhibiting the secretion of oxidative damage factors NOS2 and COX2, and enhancing the antioxidant stress ability, thus playing an antioxidant role. In summary, NAR can relieve severe lung injury caused by APP by reducing excessive inflammatory response and improving antioxidant capacity.

The impact of antenatal cluster management on maternal delivery and postpartum rehabilitation.

OBJECTIVE: Pregnancy care can improve maternal pregnancy outcomes. Cluster nursing, an evidence-based, patient-centered model, enhances pregnancy care, can provide patients with high-quality nursing services, has been widely used in clinical practice in recent years. However, most previous studies evaluated cluster nursing program only for a single clinical scenario. In this study, we developed and implemented a antenatal cluster care program for various prenatal issues faced by puerpera to analyze its application effect. METHODS: This is a historical before and after control study. 89 expectant mothers who had their prenatal information files registered in the outpatient department of a grade III, level A hospital from June 2020 to September 2021 were finally enrolled in observation group, and received prenatal cluster management. Another set of 89 expectant mothers from January 2019 to December 2019 were included in the control group and received traditional routine prenatal management. The effect of cluster nursing management on maternal delivery and postpartum rehabilitation was evaluated and compared between the two groups. RESULTS: Compared with the control group, the observation group had a significantly higher natural delivery rate, better neonatal prognosis, higher rates of exclusive breastfeeding, lower incidence of postpartum complications, shorter postpartum hospital stay, better postpartum health status, and higher satisfaction with nursing services. Compared with before intervention, the SAS and SDS scores of the observation group showed significant improvement after intervention. CONCLUSION: Antenatal cluster care is beneficial to improve maternal and neonatal outcomes, and can have positive effects on natural pregnancy and breastfeeding, while improving the multimedia health education ability of medical care and emphasizing the importance of social support.

P450-Modified Multicyclic Cyclophane-Containing Ribosomally Synthesized and Post-Translationally Modified Peptides.

Cyclic peptides with cyclophane linkers are an attractive compound type owing to the fine-tuned rigid three-dimensional structures and unusual biophysical features. Cytochrome P450 enzymes are capable of catalyzing not only the C-C and C-O oxidative coupling reactions found in vancomycin and other nonribosomal peptides (NRPs), but they also exhibit novel catalytic activities to generate cyclic ribosomally synthesized and post-translationally modified peptides (RiPPs) through cyclophane linkage. To discover more P450-modified multicyclic RiPPs, we set out to find cryptic and unknown P450-modified RiPP biosynthetic gene clusters (BGCs) through genome mining. Synergized bioinformatic analysis reveals that P450-modified RiPP BGCs are broadly distributed in bacteria and can be classified into 11 classes. Focusing on two classes of P450-modified RiPP BGCs where precursor peptides contain multiple conserved aromatic amino acid residues, we characterized 11 novel P450-modified multicyclic RiPPs with different cyclophane linkers through heterologous expression. Further mutation of the key ring-forming residues and combinatorial biosynthesis study revealed the order of bond formation and the specificity of P450s. This study reveals the functional diversity of P450 enzymes involved in the cyclophane-containing RiPPs and indicates that P450 enzymes are promising tools for rapidly obtaining structurally diverse cyclic peptide derivatives.

Methionine deficiency facilitates antitumour immunity by altering m6A methylation of immune checkpoint transcripts.

OBJECTIVE: Methionine metabolism is involved in a myriad of cellular functions, including methylation reactions and redox maintenance. Nevertheless, it remains unclear whether methionine metabolism, RNA methylation and antitumour immunity are molecularly intertwined. DESIGN: The antitumour immunity effect of methionine-restricted diet (MRD) feeding was assessed in murine models. The mechanisms of methionine and YTH domain-containing family protein 1 (YTHDF1) in tumour immune escape were determined in vitro and in vivo. The synergistic effects of MRD or YTHDF1 depletion with PD-1 blockade were also investigated. RESULTS: We found that dietary methionine restriction reduced tumour growth and enhanced antitumour immunity by increasing the number and cytotoxicity of tumour-infiltrating CD8+ T cells in different mouse models. Mechanistically, the S-adenosylmethionine derived from methionine metabolism promoted the N6-methyladenosine (m6A) methylation and translation of immune checkpoints, including PD-L1 and V-domain Ig suppressor of T cell activation (VISTA), in tumour cells. Furthermore, MRD or m6A-specific binding protein YTHDF1 depletion inhibited tumour growth by restoring the infiltration of CD8+ T cells, and synergised with PD-1 blockade for better tumour control. Clinically, YTHDF1 expression correlated with poor prognosis and immunotherapy outcomes for cancer patients. CONCLUSIONS: Methionine and YTHDF1 play a critical role in anticancer immunity through regulating the functions of T cells. Targeting methionine metabolism or YTHDF1 could be a potential new strategy for cancer immunotherapy.

Ceramides regulate defense response by binding to RbohD in Arabidopsis.

Sphingolipids, a class of bioactive lipids, play a critical role in signal transduction. Ceramides, which are central components of sphingolipid metabolism, are involved in plant development and defense. However, the mechanistic link between ceramides and downstream signaling remains unclear. Here, the mutation of alkaline ceramidase in a ceramide kinase mutant acd5 resulted in spontaneous programmed cell death early in development and was accompanied by ceramide accumulation, while other types of sphingolipids, such as long chain base, glucosylceramide, and glycosyl inositol phosphorylceramide, remained at the same level as the wild-type plants. Analysis of the transcriptome indicated that genes related to the salicylic acid (SA) pathway and oxidative stress pathway were induced dramatically in acer acd5 plants. Comparison of the level of reactive oxygen species (ROS), SA, and ceramides in the wild-type and acer acd5 plants at different developmental stages indicated that the acer acd5 mutant exhibited constitutive activation of SA and ROS signaling, which occurred simultaneously with the alteration of ceramides. Overexpressing NahG in the acer acd5 mutant could completely suppress its cell death and ceramide accumulation, while benzo-(1,2,3)-thiadiazole-7-carbothioc acid S-methyl ester treatment restored its phenotype again. Moreover, we found that the plasma membrane of acer acd5 mutant was the main site of ROS production. Ceramides accumulated in the plasma membrane of acer acd5, directly binding and activating the NADPH oxidase RbohD and promoting hydrogen peroxide generation and SA- or defense-related gene activation. Our data illustrated that ceramides play an essential role in plant defense.

P450-Modified Ribosomally Synthesized Peptides with Aromatic Cross-Links.

Cyclization of linear peptides is an effective strategy to convert flexible molecules into rigid compounds, which is of great significance for enhancing the peptide stability and bioactivity. Despite significant advances in the past few decades, Nature and chemists' ability to macrocyclize linear peptides is still quite limited. P450 enzymes have been reported to catalyze macrocyclization of peptides through cross-linkers between aromatic amino acids with only three examples. Herein, we developed an efficient workflow for the identification of P450-modified RiPPs in bacterial genomes, resulting in the discovery of a large number of P450-modified RiPP gene clusters. Combined with subsequent expression and structural characterization of the products, we have identified 11 novel P450-modified RiPPs with different cross-linking patterns from four distinct classes. Our results greatly expand the structural diversity of P450-modified RiPPs and provide new insights and enzymatic tools for the production of cyclic peptides.