[18F]AlF-NOTA-PCP2: a novel PET/CT tracer for enhanced PD-L1 heterogeneity imaging and comparative analysis with [18F]AlF-NOTA-WL12 in glioblastoma xenografts.

PURPOSE: The unsatisfactory efficacy of PD-L1 antibodies in glioblastoma (GBM) is largely due to the temporal and spatial heterogeneity of PD-L1 expression. Molecular imaging can enhance understanding of the tumor immune microenvironment and guide immunotherapy. However, highly sensitive imaging agents capable of effectively visualizing PD-L1 heterogeneity are limited. This study introduces a novel PET tracer, offering improved imaging of PD-L1 heterogeneity in GBM xenografts, with a comparative analysis to [18F]AlF-NOTA-WL12. METHODS: [18F]AlF-NOTA-PCP2 was synthesized with high purity and its affinity for PD-L1 was characterized using surface plasmon resonance (SPR) and cell binding assays. Its specificity for PD-L1 was evaluated both in vitro using various cell lines and in vivo with GBM xenograft models in NOD/SCID mice. PET/CT imaging was conducted to evaluate the tracer's biodistribution, pharmacokinetics, and ability to quantify tumoral spatial heterogeneity of PD-L1 expression. A focused comparative analysis between [18F]AlF-NOTA-PCP2 and [18F]AlF-NOTA-WL12 was conducted, examining binding affinity, biodistribution, pharmacokinetics, and imaging effectiveness in GBM xenografts. Additionally, human radiation dosimetry estimates compared the safety profiles of both tracers. RESULTS: [18F]AlF-NOTA-PCP2 demonstrated high radiochemical purity (> 95%) and a strong affinity for PD-L1, comparable to [18F]AlF-NOTA-WL12. In vitro and in vivo studies confirmed its specificity for PD-L1, with increased uptake in PD-L1 expressing cells and tumors. Toxicological profiles indicated no significant abnormalities in serum biochemical indicators or major organ tissues. MicroPET/CT imaging showed [18F]AlF-NOTA-PCP2's effectiveness in visualizing PD-L1 expression levels and spatial heterogeneity in GBM xenografts. Comparative studies revealed [18F]AlF-NOTA-PCP2's improved pharmacokinetic properties, including higher tumor-to-blood ratios and lower nonspecific liver uptake, as well as reduced radiation exposure compared to [18F]AlF-NOTA-WL12. CONCLUSION: [18F]AlF-NOTA-PCP2 distinguishes itself as an exceptionally sensitive PET/CT tracer, adept at non-invasively and accurately quantifying PD-L1 expression and its spatial heterogeneity in tumors, especially in GBM. Its favorable pharmacokinetic properties, safety profile, and high affinity for PD-L1 highlight its potential for enhancing the precision of cancer immunotherapy and guiding individualized treatment strategies. While promising, its clinical translation, especially in brain imaging, necessitates further validation in clinical trials.

Dynamic network biomarker C1QTNF1 regulates tumor formation at the tipping point of hepatocellular carcinoma.

Identifying the precise moment before the onset of hepatocellular carcinoma (HCC) remains a significant challenge in the medical field. The existing biomarkers fall short of pinpointing the critical point preceding HCC formation. This study aimed to determine the exact tipping point for the transition from cirrhosis to HCC, identify the core Dynamic Network Biomarker (DNB), and elucidate its regulatory effects on HCC. A spontaneous HCC mouse model was established to mimic HCC formation in patients with chronic hepatitis. Using the DNB method, C1q and tumor necrosis factor (TNF) related 1 (C1QTNF1) protein was identified as the key DNB at the crucial tipping time of spontaneous HCC development. Both in vitro and in vivo studies showed that C1QTNF1 could inhibit tumor growth. Overexpression of C1QTNF1 before the tipping point effectively prevented HCC occurrence. Patients with elevated C1QTNF1 expression demonstrated improved overall survival (OS) (P = 0.03) and disease-free survival (DFS) (P = 0.03). The diagnostic value of C1QTNF1 was comparable to that of alpha-fetoprotein (AFP) (area under the curve [AUC] = 0.84; sensitivity 85%; specificity 80%). Furthermore, our research indicated that platelet-expressed C1QTNF1 is involved in cancer-associated signaling pathways. Our findings introduce a novel perspective by highlighting C1QTNF1 as the pivotal biomarker at the tipping point of primary HCC formation using DNB. We propose C1QTNF1 as a prognostic biomarker for HCC, potentially influencing tumor development through a platelet-related cancer signaling pathway.

Cell-free DNA methylation profile potential in the diagnosis of lung squamous cell carcinoma.

Background: Aberrant methylation plays an essential role in early cancer development. In this study, we investigated methylation patterns in lung squamous cell carcinoma (LUSC) and matched non-tumor tissue and plasma samples to evaluate the potential of these patterns in the diagnosis of LUSC. Methods: The study group included 49 patients with stage I-III LUSC. We collected resected tumor tissue, paired peritumoral tissue, distant normal tissue, and corresponding plasma samples. A bespoke lung cancer bisulfite sequencing panel was used to profile the methylation level. Another 48 healthy volunteers provided control plasma samples. Results: Peritumoral and distant normal tissues presented similar methylation signatures, distinct from those in tumor tissue samples. A comparison of methylation profiles led to the identification of 871 tumor-specific differentially methylated blocks, including 847 hypermethylated and 24 hypomethylated blocks (adjusted P value <0.05). All top-ranked blocks were tumor-related. Tissue samples were analyzed for field cancerization to identify progressively aggravating aberrant methylations during tumor initiation and development. The analysis revealed that 221 blocks presented a stepwise increase in methylation levels, while seven blocks presented a stepwise decrease in methylation pattern as the sampling drew nearer to the tumor. The malignant contaminated ratio (MCR) confirmed the presence of distinct methylation patterns between tumor and peritumoral tissue samples. We then constructed a diagnostic panel using a combined diagnostic score of cell-free DNA (cfDNA) that showed high sensitivity and specificity. The healthy controls had a significantly lower combined diagnostic score (cd-score) than LUSC patients. Additionally, based on the methylation profiles, LUSC could be classified into two subgroups, C1 and C2. The methylation profile of the C2 group was not distinct from the healthy controls, which had a significantly lower cd-score than did the C1 group. Conclusions: LUSC-specific methylation patterns could potentially discriminate between peritumoral tissue, distant normal tumor tissue, and tumor tissues. This preliminary study also supported the potential utility of cfDNA methylation analysis in diagnosing LUSC.

PET Imaging of Peptide Probe Al[18F]F-NOTA-PCP1 for Monitoring the Engagement of PD-L1 Antibodies in Tumors.

Immune checkpoint inhibitors (ICIs) are a powerful treatment modality for various types of cancer. The effectiveness of ICIs is intimately connected to the binding status of antibodies to receptors. However, validated means to accurately evaluate target specificity and predict antibody efficacy in vivo are lacking. A novel peptide-based probe called Al[18F]F-NOTA-PCP1 was developed and validated for its specificity to PD-L1 in A549, U87MG, GL261, and GL261-iPDL1 cell lines, as well as in xenograft models. Then the probe was used in PET/CT scans to determine the binding status of PD-L1 antibodies (atezolizumab, avelumab, and durvalumab) in U87MG xenograft model mice. Moreover, Al[18F]F-NOTA-PCP1 was used to evaluate the impact of different treatment times and doses. Al[18F]F-NOTA-PCP1 PET/CT can be used to evaluate the interaction between PD-L1 and antibodies to determine the effectiveness of immunotherapy. By quantifying target engagement, the probe has the potential to predict the efficacy of immunotherapy and optimize the dose and treatment schedules for PD-L1 immunotherapy. This imaging agent could be a valuable tool in guiding personalized treatment strategies and improving cancer patient outcomes.

Neo-adjuvant chemotherapy plus immunotherapy in resectable N1/N2 NSCLC.

BACKGROUND: Locally advanced non-small cell lung cancer (NSCLC) with N1/N2 lymph node metastasis is challenging with poor survival. Neo-adjuvant chemo-immunotherapy has gained benefits in a proportion of these patients. However no specific biomarker has been proved to predict the effect before therapy. In addition, the relationship of nodal status and survival after neo-adjuvant chemo-immunotherapy is still not well stated. METHODS: A total of 75 resectable NSCLC patients with N1/N2 stage who received neo-adjuvant chemo-immunotherapy plus surgery were retrospectively studied. The clinical characteristics, surgical information and safety parameters were collected. The correlations of major pathological response (MPR) and pathological complete response (pCR) with clinical data were analyzed. The progression free disease(PFS) and overall survival(OS) were evaluated with pathological response and nodal status. RESULTS: Of the 75 patients, 69 (92%) patients experienced treatment related adverse effects, while grade 3-4 adverse effects occurred in 8 (10%) patients. All the patients received surgical R0 resection with a MPR rate of 60% and a pCR rate of 36%. 67% of N1 patients and 77% of N2 patients had nodal clearance after neo-adjuvant treatment. A significant difference was observed between pathological response with age, histology and multiple lymph node metastasis. The PFS was better in the MPR cohort. The PFS was 90.1% and 83.6% at the nodal clearance group at the time of 12 and 18 months, compared with 70.1% and 63.7% at the nodal residual group. CONCLUSIONS: The neo-adjuvant chemo-immunotherapy for locally advanced NSCLC with nodal positive was safe and feasible. The patients with elder age and squamous-cell carcinoma (SCC) were more likely to have better pathological response, while multiple nodal metastasis was a negative predictor. The clearance of lymph node resulted in significantly longer PFS and OS.

Risk factor analysis and prediction model for papillary thyroid carcinoma with lymph node metastasis.

Objective: We aimed to identify the clinical factors associated with lymph node metastasis (LNM) based on ultrasound characteristics and clinical data, and develop a nomogram for personalized clinical decision-making. Methods: A retrospective analysis was performed on 252 patients with papillary thyroid carcinoma (PTC). The patient's information was subjected to univariate and multivariate logistic regression analyses to identify risk factors. A nomogram to predict LNM was established combining the risk factors. The performance of the nomogram was evaluated using receiver operating characteristic (ROC) curve, calibration curve, cross-validation, decision curve analysis (DCA), and clinical impact curve. Results: There are significant differences between LNM and non-LNM groups in terms of age, sex, tumor size, hypoechoic halo around the nodule, thyroid capsule invasion, lymph node microcalcification, lymph node hyperechoic area, peak intensity of contrast (PI), and area under the curve (AUC) of the time intensity curve of contrast (P<0.05). Age, sex, thyroid capsule invasion, lymph node microcalcification were independent predictors of LNM and were used to establish the predictive nomogram. The ROC was 0.800, with excellent discrimination and calibration. The predictive accuracy of 0.757 and the Kappa value was 0.508. The calibration curve, DCA and calibration curve demonstrated that the prediction model had excellent net benefits and clinical practicability. Conclusion: Age, sex, thyroid capsule invasion, and lymph node microcalcification were identified as significant risk factors for predicting LNM in patients with PTC. The visualized nomogram model may assist clinicians in predicting the likelihood of LNM in patients with PTC prior to surgery.

N6 -methyladenosine-modified circSTX6 promotes hepatocellular carcinoma progression by regulating the HNRNPD/ATF3 axis and encoding a 144 amino acid polypeptide.

BACKGROUND: Circular RNAs (circRNAs) play a significant role in the initiation and progression of various cancers, including hepatocellular carcinoma (HCC). Circular syntaxin 6 (circSTX6, also known as hsa_circ_0007905) has been identified as a microRNA (miRNA) sponge in pancreatic adenocarcinoma. However, its full range of functions in terms of protein scaffold and translation remain largely unexplored in the context of HCC. METHODS: The expression of circSTX6 and its encoded protein was examined in HCC tumour tissues. N6 -methyladenosine (m6 A) on circSTX6 was verified and quantified by methylated RNA immunoprecipitation (Me-RIP), RIP and dual luciferase reporter assays. The biological functions of circSTX6 and its encoded protein in HCC were clarified by in vitro and in vivo experiments. Mechanistically, the interaction between circSTX6 and heterogeneous nuclear ribonucleoprotein D (HNRNPD) was investigated by RNA pull-down, RIP and fluorescence in situ hybridization (FISH)/IF. The regulatory effects of circSTX6 and HNRNPD on activating transcription factor 3 (ATF3) mRNA were determined by mRNA stability and RIP assays. Furthermore, the presence of circSTX6-encoded protein was verified by mass spectrometry. RESULTS: CircSTX6 and its encoded 144 amino acid polypeptide, circSTX6-144aa, were highly expressed in HCC tumour tissues and served as independent risk factors for overall survival in HCC patients. The expression of circSTX6 was regulated by METTL14 in an m6 A-dependent manner. Functionally, circSTX6 accelerated HCC proliferation and tumourigenicity and reinforced tumour metastasis in vitro and in vivo. Mechanistically, circSTX6 acted as a sponge for HNRNPD protein, facilitating its binding to ATF3 mRNA, consequently promoting ATF3 mRNA decay. Meanwhile, circSTX6-144aa promoted HCC proliferation, migration and invasion independent of circSTX6 itself. CONCLUSION: Collectively, our study reveals that m6 A-modified circSTX6 drives malignancy in HCC through the HNRNPD/ATF3 axis, while its encoded circSTX6-144aa contributes to HCC progression independent of circSTX6. CirSTX6 and its encoded protein hold promise as potential biomarkers and therapeutic targets in HCC.

An overview of current advances of PD-L1 targeting immuno-imaging in cancers.

The programmed death protein 1/programmed cell death ligand 1 (PD-1/PD-L1) pathway plays a significant role in immune evasion. PD-1 or PD-L1 immune checkpoint inhibitors (ICIs) have become a standard treatment for multiple types of cancer. To date, PD-L1 has served as a biomarker for predicting the efficacy of ICIs in several cancers. The need to establish an effective detection method that could visualize PD-L1 expression and predict the efficacy of PD-1/PD-L1 ICIs has promoted a search for new imaging strategies. PD-L1-targeting immuno-imaging could provide a noninvasive, real-time, repeatable, dynamic, and quantitative assessment of the characteristics of all tumor lesions in individual patients. This study analyzed the existing evidence in the literature on PD-L1-based immuno-imaging (2015-2022). Original English-language articles were searched using PubMed and Google Scholar. Keywords, such as "PD-L1," "PET," "SPECT," "PET/CT," and "SPECT/CT," were used in various combinations. A total of nearly 50 preclinical and clinical studies of PD-L1-targeting immuno-imaging were selected, reviewed, and included in this study. Therefore, in this review, we conducted a study of the advances in PD-L1-targeting immuno-imaging for detecting the expression of PD-L1 and the efficacy of ICIs. We focused on the different types of PD-L1-targeting agents, including antibodies and small PD-L1-binding agents, and illustrated the strength and weakness of these probes. Furthermore, we summarized the trends in the development of PD-L1-targeting immuno-imaging, as well as the current challenges and future directions for clinical workflow.

The current advances and future directions of PD-1/PD-L1 blockade in head and neck squamous cell carcinoma (HNSCC) in the era of immunotherapy.

Immune checkpoint inhibitors (ICIs) have previously demonstrated their efficacy and safety in various solid tumors, and with the growing interest in the application of ICIs in head and neck squamous cell carcinoma (HNSCC), various data have been reported. Mechanistically, HNSCC cells express programmed death ligand 1 (PD-L1), which binds to its receptor programmed death 1 (PD-1). Immune escape plays a key role in disease initiation and progression. Studying the abnormal activation of related pathways of PD-1/PD-L1 will help to understand the way of immunotherapy and find the advantageous population of immunotherapy. How to reduce HNSCC-related mortality and morbidity in this process has promoted the search for new therapeutic strategies, especially in the era of immunotherapy. PD-1 inhibitors have demonstrated significant prolongation of survival in recurrent/metastatic (R/M) HNSCC with a favorable safety profile. It also holds great promise in locally advanced (LA) HNSCC, where numerous studies are underway. Although immunotherapy has made great progress in HNSCC research, there are still many challenges. Therefore, in the review, we conducted an in-depth study on the expression of PD-L1 and the regulatory, immunosuppressive mechanisms caused by PD-L1, especially in head and neck squamous cell carcinoma, which is different from other tumors. And further summarize the situation, challenges and development trends of PD-1 and PD-L1 blockade in clinical practice.

m6A-modification regulated circ-CCT3 acts as the sponge of miR-378a-3p to promote hepatocellular carcinoma progression.

Background: Circular RNA (circRNA) plays a critical role in tumour progression. Circ-CCT3, a particularly abundant circRNA, was proposed to be involved in tumorigenesis. However, the role of circ-CCT3 in hepatocellular carcinoma remains elusive.Methods: Here, circ-CCT3 (a circRNA derived from exons 3, 4 and 5 of the CCT3 gene, hsa_circ_0004680) was identified by circRNA microarray and validated by qRT-PCR. RNA immunoprecipitation (RIP) was performed to confirm the binding between ALKBH5 along with METTL3 and circ-CCT3. Methylated RNA Immunoprecipitation (MeRIP) was used to detect the N6-methyladenosine (m 2A) levels of circ-CCT3. CircRNAs in vivo precipitation, luciferase reporter assay, biotin-coupled microRNA capture, and fluorescence in situ hybridization were conducted to assess the interaction between circ-CCT3 and miR-378a-3p. The functions of circ-CCT3 in HCC were evaluated both in vitro and in vivo.Results: We demonstrated that circ-CCT3 was highly expressed in HCC which indicated the poor prognosis. Circ-CCT3 expression served as an independent risk factor for overall survival in patients with HCC. Knocking-down of circ-CCT3 inhibited the proliferation, invasion and migration of HCC cells, and angiogenesis of HUVEC. Mechanistically, ALKBH5 and METTL3 could bind and regulate m A-modification of circ-CCT3. Further, circ-CCT3 upregulated the expression of FLT-1 by sponging miR-378a-3p.Conclusions: Circ-CCT3 was significantly up-regulated in HCC and promoted liver cancer development via miR-378a-3p-FLT1 axis. It was also found that circ-CCT3 was under m A-modification mediated by ALKBH5 and METTL3. Our study highlights circ-CCT3 as a potential therapeutic target of HCC treatment, which provides a novel understanding on mechanisms of circRNAs in HCC progression.

Messenger RNA electroporated hepatitis B virus (HBV) antigen-specific T cell receptor (TCR) redirected T cell therapy is well-tolerated in patients with recurrent HBV-related hepatocellular carcinoma post-liver transplantation: results from a phase I trial.

BACKGROUND AND AIMS: Liver transplantation (LT) is the primary curative option for cirrhotic patients with early-stage hepatocellular carcinoma (HCC). However, tumor recurrence occurs in 15-20% of cases with unfavorable prognosis. We have developed a library of T cell receptors (TCRs) specific for different hepatitis B virus (HBV) antigens, restricted by different molecules of human leucocyte antigen (HLA)-class I, to redirect T cells against HBV antigens (Banu in Sci Rep 4:4166, 2014). We further demonstrated that these transiently functional T cells specific for HBV obtained through messenger RNA (mRNA) electroporation can eliminate HCC cells expressing HBV antigens in vitro and in vivo (Kah in J Clin Invest 127:3177-3188, 2017). A phase I clinical trial for patients with HCC recurrence post-liver transplant was conducted to assess the safety, tolerability, and anti-tumor efficacy of transiently functional HBV-TCR T cells. Here, we report the clinical findings with regard to the safety and anti-tumor efficacy of mRNA electroporated HBV-specific TCR-T cells. (ClinicalTrials.gov identifier: NCT02719782). PATIENTS AND METHODS: A total of six patients with HBV-positive recurrent HCC post-liver transplant and HLA-matched to TCR targeting hepatitis B surface antigen (HBsAg) or hepatitis B core antigen (HBcAg) (HLA-A*02:01/HBsAg, HLA-A*11:01/HBcAg, HLA-B*58:01/HBsAg or HLA-C*08:01/HBsAg) were enrolled in this study. The primary objective was to assess the safety of short-lived mRNA electroporated HBV-TCR T cells based on the incidence and severity of the adverse event (AE) graded per National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE), Version 4.0. The secondary objective was to determine the effectiveness of HBV-TCR T cells as per RECIST 1.1 criteria. Patients were followed up for survival for 2 years post-end of treatment. RESULTS: The median age of the six patients was 35.5 years (range: 28-47). The median number of HBV-TCR T cell infusions administered was 6.5 (range: 4-12). The treatment-related AE included grade 1 pyrexia. This study reported no cytokine release syndrome nor neurotoxicity. One patient remained alive and five were deceased at the time of the data cutoff (30 April 2020). CONCLUSION: This study has demonstrated that multiple infusions of mRNA electroporated HBV-specific TCR T cells were well-tolerated in patients with HBV-positive recurrent HCC post-liver transplant.

Retraction Notice to: LINC01234/MicroRNA-31-5p/MAGEA3 Axis Mediates the Proliferation and Chemoresistance of Hepatocellular Carcinoma Cells.

[This retracts the article DOI: 10.1016/j.omtn.2019.10.035.].

Evaluation of diagnostic efficacy of multimode ultrasound in BI-RADS 4 breast neoplasms and establishment of a predictive model.

Objectives: To explore the diagnostic efficacy of ultrasound (US), two-dimensional and three-dimensional shear-wave elastography (2D-SWE and 3D-SWE), and contrast-enhanced ultrasound (CEUS) in breast neoplasms in category 4 based on the Breast Imaging Reporting and Data System (BI-RADS) from the American College of Radiology (ACR) and to develop a risk-prediction nomogram based on the optimal combination to provide a reference for the clinical management of BI-RADS 4 breast neoplasms. Methods: From September 2021 to April 2022, a total of 104 breast neoplasms categorized as BI-RADS 4 by US were included in this prospective study. There were 78 breast neoplasms randomly assigned to the training cohort; the area under the receiver-operating characteristic curve (AUC), 95% confidence interval (95% CI), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 2D-SWE, 3D-SWE, CEUS, and their combination were analyzed and compared. The optimal combination was selected to develop a risk-prediction nomogram. The performance of the nomogram was assessed by a validation cohort of 26 neoplasms. Results: Of the 78 neoplasms in the training cohort, 16 were malignant and 62 were benign. Among the 26 neoplasms in the validation cohort, 6 were malignant and 20 were benign. The AUC values of 2D-SWE, 3D-SWE, and CEUS were not significantly different. After a comparison of the different combinations, 2D-SWE+CEUS showed the optimal performance. Least absolute shrinkage and selection operator (LASSO) regression was used to filter the variables in this combination, and the variables included Emax, Eratio, enhancement mode, perfusion defect, and area ratio. Then, a risk-prediction nomogram with BI-RADS was built. The performance of the nomogram was better than that of the radiologists in the training cohort (AUC: 0.974 vs. 0.863). In the validation cohort, there was no significant difference in diagnostic accuracy between the nomogram and the experienced radiologists (AUC: 0.946 vs. 0.842). Conclusions: US, 2D-SWE, 3D-SWE, CEUS, and their combination could improve the diagnostic efficiency of BI-RADS 4 breast neoplasms. The diagnostic efficacy of US+3D-SWE was not better than US+2D-SWE. US+2D-SWE+CEUS showed the optimal diagnostic performance. The nomogram based on US+2D-SWE+CEUS performs well.

Activation of YAP1 by N6-Methyladenosine-Modified circCPSF6 Drives Malignancy in Hepatocellular Carcinoma.

Circular RNAs (circRNA) and N6-methyladenosine (m6A) modification are extensively involved in the progression of diverse tumors, including hepatocellular carcinoma (HCC). However, the cross-talk between circRNAs and m6A remains elusive in the pathogenesis of HCC. Here we investigated m6A-mediated regulation of circRNAs in HCC. m6A-related circRNAs were identified by integrating information from two published studies, revealing circular cleavage and polyadenylation specific factor 6 (circCPSF6) as a novel m6A-modified circRNA. circCPSF6 was dominated by ALKBH5-mediated demethylation, followed by the recognization and destabilization by YTHDF2. Meanwhile, circCPSF6 was upregulated in HCC specimens, and elevated circCPSF6 expression served as an independent prognostic factor for worse survival of patients with HCC. Loss-of-function assays demonstrated that circCPSF6 maintained cell proliferation and tumorigenicity and reinforced cell motility and tumor metastasis. circCPSF6 triggered expression of YAP1, further activating its downstream cascade. Mechanistically, circCPSF6 competitively bound PCBP2, blunting its binding to YAP1 mRNA, thereby sustaining the stability of YAP1. Functionally, removal of YAP1 reversed the effects of circCPSF6 in vitro and in vivo. Aberrant activation of the circCPSF6-YAP1 axis promoted HCC malignancy. These findings offer novel insights into the regulation of circRNAs by m6A modifications and the role of this epigenetic reprogramming in HCC. SIGNIFICANCE: This study advances the understanding of the interplay between m6A methylation and circRNAs in hepatocellular carcinoma, highlighting the potential of circCPSF6 as a therapeutic target.

A plasmid-free Zymomonas mobilis mutant strain reducing reactive oxygen species for efficient bioethanol production using industrial effluent of xylose mother liquor.

Genome minimization is an effective way for industrial chassis development. In this study, Zymomonas mobilis ZMNP, a plasmid-free mutant strain of Z. mobilis ZM4 with four native plasmids deleted, was constructed using native type I-F CRISPR-Cas system. Cell growth of ZMNP under different temperatures and industrial effluent of xylose mother liquor were examined to investigate the impact of native plasmid removal. Despite ZMNP grew similarly as ZM4 under different temperatures, ZMNP had better xylose mother liquor utilization than ZM4. In addition, genomic, transcriptomic, and proteomic analyses were applied to unravel the molecular changes between ZM4 and ZMNP. Whole-genome resequencing result indicated that an S267P mutation in the C-terminal of OxyR, a peroxide-sensing transcriptional regulator, probably alters the transcription initiation of antioxidant genes for stress responses. Transcriptomic and proteomic studies illustrated that the reason that ZMNP utilized the toxic xylose mother liquor better than ZM4 was probably due to the upregulation of genes in ZMNP involving in stress responses as well as cysteine biosynthesis to accelerate the intracellular ROS detoxification and nucleic acid damage repair. This was further confirmed by lower ROS levels in ZMNP compared to ZM4 in different media supplemented with furfural or ethanol. The upregulation of stress response genes due to the OxyR mutation to accelerate ROS detoxification and DNA/RNA repair not only illustrates the underlying mechanism of the robustness of ZMNP in the toxic xylose mother liquor, but also provides an idea for the rational design of synthetic inhibitor-tolerant microorganisms for economic lignocellulosic biochemical production.

RBM15 promotes hepatocellular carcinoma progression by regulating N6-methyladenosine modification of YES1 mRNA in an IGF2BP1-dependent manner.

The function of the N6-methyladenosine (m6A) methyltransferase RNA-binding motif protein 15 (RBM15) in hepatocellular carcinoma (HCC) has not been thoroughly investigated. Here we determined the clinical value, biological functions, and potential mechanisms of RBM15 in HCC. Expression of RBM15 was identified using tissue microarrays and online databases. A risk-prediction model based on RBM15 was developed and validated. We determined the biological role of RBM15 on HCC cells in vitro and in vivo. RNA sequencing was used to screen candidate targets of RBM15. Subsequently, the m6A dot blot assay, methylated RNA immunoprecipitation qPCR, dual-luciferase reporter assays, RNA decay assay, and RNA immunoprecipitation qPCR were employed to explore the mechanisms of RBM15. Our study showed that RBM15 was highly expressed in HCC, and overexpression of RBM15 indicated a worse outcome. A new nomogram combining RBM15 with age and TNM stage was developed and validated to predict the outcome of HCC patients; our nomogram increased the prediction accuracy of the TNM system. Functionally, RBM15 facilitates the proliferation and invasiveness of HCC. RBM15-mediated m6A modification contributed to a post-transcriptional activation of YES proto-oncogene 1 (YES1) in an insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1)-dependent manner. In addition, YES1 was confirmed as an oncogene in HCC cells by activating the mitogen-activated protein kinase (MAPK) pathway. In conclusion, RBM15-mediated m6A modification might facilitate the progression of HCC via the IGF2BP1-YES1-MAPK axis. RBM15 may be a promising biomarker in the outcome prediction of HCC.

VIRMA contributes to non-small cell lung cancer progression via N6-methyladenosine-dependent DAPK3 post-transcriptional modification.

N6-methyladenosine (m6A) has been reported to be abnormally expressed in non-small cell lung cancer (NSCLC), and plays a vital role in regulation of cell proliferation, invasion and metastasis. Vir-Like m6A methyltransferase associated (VIRMA, also called KIAA1429) has not been well studied in NSCLC. Thus, in this study, we investigated the biological impact and underlying mechanism of VIRMA in NSCLC. High expression of VIRMA was testified in patients with NSCLC and predicted worse prognosis in patients. VIRMA facilitated cell proliferation and tumor growth both in vitro and in vivo. Furthermore, VIRMA-regulated m6A modifications led to post-transcriptional suppression of death-associated protein kinase 3 (DAPK3, also called ZIP or ZIPK) through the YT521-B homology domain-containing family proteins 2/3(YTHDF2/3). Inhibition of DAPK3 rescued the tumor-suppressive phenotypes induced by VIRMA deficiency. In conclusion, VIRMA-guided m6A modifications promoted NSCLC progression via m6A-dependent degradation of DAPK3 mRNA. Therefore, VIRMA may be a novel therapeutic target in NSCLC.

The crosstalk between m6A RNA methylation and other epigenetic regulators: a novel perspective in epigenetic remodeling.

Epigenetic regulation involves a range of sophisticated processes which contribute to heritable alterations in gene expression without altering DNA sequence. Regulatory events predominantly include DNA methylation, chromatin remodeling, histone modifications, non-coding RNAs (ncRNAs), and RNA modification. As the most prevalent RNA modification in eukaryotic cells, N6-methyladenosine (m6A) RNA methylation actively participates in the modulation of RNA metabolism. Notably, accumulating evidence has revealed complicated interrelations occurring between m6A and other well-known epigenetic modifications. Their crosstalk conspicuously triggers epigenetic remodeling, further yielding profound impacts on a variety of physiological and pathological processes, especially tumorigenesis. Herein, we provide an up-to-date review of this emerging hot area of biological research, summarizing the interplay between m6A RNA methylation and other epigenetic regulators, and highlighting their underlying functions in epigenetic reprogramming.