Proximity-Enhanced Functional Imaging Analysis of Engineered Tumors.

Functional imaging (FI) techniques have revolutionized tumor imaging by providing information on specific tumor functions, such as glycometabolism. However, tumor cells lack unique molecular characteristics at the molecular level and metabolic pathways, resulting in limited metabolic differences compared to normal cells and increased background signals from FI. To address this limitation, we developed a novel imaging technique termed proximity-enhanced functional imaging (PEFI) for accurate visualization of tumors. By using "two adjacent chemically labeled glycoproteins" as output signals, we significantly enhance the metabolic differences between tumor and normal cells by PEFI, thereby reducing the background signals for analysis and improving the accuracy of tumor functional imaging. Our results demonstrate that PEFI can accurately identify tumors at the cellular, tissue, and animal level, and has potential value in clinical identification and analysis of tumor cells and tissues, as well as in the guidance of clinical tumor resection surgery.

Phase separation of YAP mediated by coiled-coil domain promotes hepatoblastoma proliferation via activation of transcription.

AIM AND BACKGROUND: Yes-associated protein (YAP), a key transcriptional co-activator associated with cell fate and tumor progression, has been reported to be a powerful driver of hepatoblastoma (HB). In this study, we investigated the mechanism underlying oncogenic role of YAP in HB. METHODS: The expression of YAP in HB tissues was measured through WB and qRT-PCR. The IHC and IF were performed to determine the distribution of YAP. The phase separation of YAP was proved by living cell imaging and FRAP experiment. The effect of YAP phase separation in HB cells in vitro an in vivo were tested using CCK8, flow cytometry, and xenograft tumors. RESULTS: YAP was overexpressed and activated in HB. Nuclear YAP formed an active transcriptional site via LLPS to recruit the crucial transcription factor TEAD4. Thus, YAP phase separation facilitated transcription of oncogenic genes and subsequently mediated chemoresistance of HB. Mechanistically, the phase separation ability of YAP depends on the coiled-coil domain, which is a typical phase separation domain. The electrostatic interactions and hydrophobic interactions within YAP are also vital to YAP phase separation. More importantly, YAP inhibitor verteporfin is potential treatment for HB and combination with cisplatin enhanced therapeutic efficacy. CONCLUSIONS: Highly expressed and active YAP exerts an oncogenic effect in HB via phase separation and provides new insights for the treatment of HB.

IL-27 improves adoptive CD8+ T cells' antitumor activity via enhancing cell survival and memory T cell differentiation.

IL-27 is an anti-inflammatory cytokine that triggers enhanced antitumor immunity, particularly cytotoxic T lymphocyte responses. In the present study, we sought to develop IL-27 into a therapeutic adjutant for adoptive T cell therapy using our well-established models. We have found that IL-27 directly improved the survival status and cytotoxicity of adoptive OT-1 CD8+ T cells in vitro and in vivo. Meanwhile, IL-27 treatment programs memory T cell differentiation in CD8+ T cells, characterized by upregulation of genes associated with T cell memory differentiation (T-bet, Eomes, Blimp1, and Ly6C). Additionally, we engineered the adoptive OT-1 CD8+ T cells to deliver IL-27. In mice, the established tumors treated with OT-1 CD8+ T-IL-27 were completely rejected, which demonstrated that IL-27 delivered via tumor antigen-specific T cells enhances adoptive T cells' cancer immunity. To our knowledge, this is the first application of CD8+ T cells as a vehicle to deliver IL-27 to treat tumors. Thus, this study demonstrates IL-27 is a feasible approach for enhancing CD8+ T cells' antitumor immunity and can be used as a therapeutic adjutant for T cell adoptive transfer to treat cancer.

Causal Relationship between Sex Hormone-Binding Globulin and Risk of Neuroblastoma: A Bidirectional Two-Sample Mendelian Randomization Study.

BACKGROUND: The causal relationship between sex hormone-binding globulin (SHBG) and neuroblastoma remains unknown. This study aimed to explore the causality between SHBG and the risk of neuroblastoma using bidirectional two-sample Mendelian randomization (MR) study. METHODS: Instrumental variables associated with SHBG were obtained from the genome-wide association study (GWAS) of European containing 214,989 females and 185,221 males from the UK Biobank. Summary-level data for neuroblastoma were derived from the IEU OpenGWAS project with 1,627 patients and 3,254 controls. The inverse-variance weighted (IVW) method served as the primary analytic tool. RESULTS: The IVW method revealed a significant positive causal relationship between male SHBG and the risk of neuroblastoma [OR, 2.169; 95% confidence interval (CI), 1.207-3.897; P = 0.010]. Conversely, female SHBG showed no significant causal link with neuroblastoma (IVW OR, 1.004; 95% CI, 0.542-1.860; P = 0.990). No significant reverse causality was detected. Sensitivity analyses validated these findings. CONCLUSIONS: Elevated SHBG levels in males, but not in females, can causally increase the risk of neuroblastoma. This gender-specific effect indicates a potential differential role of SHBG in the etiology of neuroblastoma. Further research is needed to elucidate the underlying mechanisms of this gender disparity. Monitoring SHBG levels, especially in males, could be pivotal in neuroblastoma risk assessment and management. IMPACT: This study highlights a novel gender-specific aspect in the risk of neuroblastoma, emphasizing the potential role of male SHBG levels in neuroblastoma incidence, and sets the stage for targeted preventative strategies and further investigation into gender-based biological mechanisms.

Anti-ferroptotic PRKAA2 serves as a potential diagnostic and prognostic marker for hepatoblastoma.

Background: The incidence rate of hepatoblastoma (HB), which is the most prevalent malignant tumour among children, rises each year. According to recent studies, a number of neoplastic disorders and ferroptosis are intimately connected. This study aims to identify key ferroptosis-related genes in HB and explore new directions for the diagnosis and treatment of HB. Methods: Differentially expressed ferroptosis-related genes were identified using the Gene Expression Omnibus datasets. The functional annotation of candidate genes was evaluated through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses. Machine learning and receiver operating characteristic (ROC) curves revealed protein kinase AMP-activated catalytic subunit alpha 2 (PRKAA2), tribbles homolog 2 (TRIB2), and liver-type glutaminase (GLS2) as potential diagnostic genes of HB. By using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and immunohistochemistry, relative expression of PRKAA2 was examined. The effect of PRKAA2 on proliferation, apoptosis, and ferroptosis of HB cells was verified in vitro and in vivo. Fisher's exact test was used to evaluate the clinical significance of PRKAA2 in HB. Results: The prognostic indicators had a substantial correlation with PRKAA2 expression, which rose dramatically in HB tissues. PRKAA2 promotes proliferation and inhibits ferroptosis in HB cells. PRKAA2 plays a role in ferroptosis by regulating hypoxia-inducible factor 1α (HIF-1α) and transferrin receptor 1 (TFR1). Conclusions: PRKAA2 functions as a tumor-promoting factor in HB by promoting cell proliferation and prohibiting ferroptosis. Ferroptosis-related genes PRKAA2 is a potential diagnostic and prognostic marker for HB as well as a novel therapeutic target in the future.

Alternative Splicing of lncRNAs From SNHG Family Alters snoRNA Expression and Induces Chemoresistance in Hepatoblastoma.

BACKGROUND & AIMS: Hepatoblastoma (HB) is a common pediatric malignant liver tumor that is characterized by a low level of genetic mutations. Alternative splicing (AS) has been shown to be closely associated with cancer progression, especially in tumors with a low mutational burden. However, the role of AS in HB remains unknown. METHODS: Transcriptome sequencing was performed on 5 pairs of HB tissues and matched non-tumor tissues to delineate the AS landscape in HB. AS events were validated in 92 samples from 46 patients. RNA pull-down and RNA immunoprecipitation assays were carried out to identify splicing factors that regulate the AS of small nucleolar RNA host genes (SNHG). Patient-derived organoids (PDOs) were established to investigate the role of the splicing factor polyadenylate-binding nuclear protein 1 (PABPN1). RESULTS: This study uncovered aberrant alternative splicing in HB, including lncRNAs from SNHG family that undergo intron retention in HB. Further investigations revealed that PABPN1, a significantly upregulated RNA binding protein, interacts with splicing machinery in HB, inducing the intron retention of these SNHG RNAs and the downregulation of intronic small nucleolar RNAs (snoRNAs). Functionally, PABPN1 acts as an oncofetal splicing regulator in HB by promoting cell proliferation and DNA damage repair via inducing the intron retention of SNHG19. Knock-down of PABPN1 increases the cisplatin sensitivity of HB PDOs. CONCLUSIONS: Our findings revealed the role of intron retention in regulating snoRNA expression in hepatoblastoma, explained detailed regulatory mechanism between PABPN1 and the intron retention of SNHG RNAs, and provided insight into the development of new HB treatment options.

SNORA14A inhibits hepatoblastoma cell proliferation by regulating SDHB-mediated succinate metabolism.

Hepatoblastoma (HB) is the most common paediatric liver malignancy. Dysregulation of small nucleolar RNAs (snoRNAs) is a critical inducer of tumour initiation and progression. However, the association between snoRNAs and HB remains unknown. Here, we conducted snoRNA expression profiling in HB by snoRNA sequencing and identified a decreased level of SNORA14A, a box H/ACA snoRNA, in HB tissues. Low expression of SNORA14A was correlated with PRETEXT stage and metastasis in patients. Functionally, overexpression of SNORA14A suppressed HB cell proliferation and triggered cell apoptosis and G2/M phase arrest. Mechanistically, SNORA14A overexpression promoted the processing and maturation of the 18 S ribosomal RNA (rRNA) precursor to increase succinate dehydrogenase subunit B (SDHB) protein levels. In accordance with SNORA14A downregulation, SDHB protein expression was significantly reduced in HB tissues and cells, accompanied by abnormal accumulation of succinate. Overexpression of SDHB showed antiproliferative and proapoptotic effects and the capacity to induce G2/M phase arrest, while succinate dose-dependently stimulated HB cell growth. Furthermore, the inhibition of SNORA14A in HB malignant phenotypes was mediated by SDHB upregulation-induced reduction of cellular succinate levels. Therefore, the SNORA14A/18 S rRNA/SDHB axis suppresses HB progression by preventing cellular accumulation of the oncometabolite succinate and provides promising prognostic biomarkers and novel therapeutic targets for HB.

O-GlcNAcylated LARP1 positively regulated by circCLNS1A facilitates hepatoblastoma progression through DKK4/ß-catenin signalling.

BACKGROUND: Accumulating studies have shown that La-related protein 1 (LARP1) is involved in the occurrence and development of various tumours. However, the expression pattern and biological role of LARP1 in hepatoblastoma (HB) remain unclear so far. METHODS: LARP1 expression level in HB and adjacent normal liver tissues was analysed by qRT-PCR, Western blotting and immunohistochemistry assays. The prognostic significance of LARP1 was evaluated by Kaplan-Meier method and multivariate Cox regression analysis. In vitro and in vivo functional assays were implemented to clarify the biological effects of LARP1 on HB cells. Mechanistically, the regulatory roles of O-GlcNAcylation and circCLNS1A in LARP1 expression were investigated by co-immunoprecipitation (co-IP), immunofluorescence, RNA immunoprecipitation (RIP), RNA pull-down and protein stability assays. Moreover, RNA-sequencing, co-IP, RIP, mRNA stability and poly(A)-tail length assays were performed to investigate the association between LARP1 and DKK4. The expression and diagnostic significance of plasma DKK4 protein in multi-centre cohorts were evaluated by ELISA and ROC curves. RESULTS: LARP1 mRNA and protein levels were remarkably elevated in HB tissues and associated with worse prognosis of HB patients. LARP1 knockdown abolished cell proliferation, triggered cell apoptosis in vitro as well as prohibited tumour growth in vivo, whereas LARP1 overexpression incited HB progression. Mechanistically, O-GlcNAcylation of LARP1 Ser672 by O-GlcNAc transferase strengthened its binding to circCLNS1A and then protected LARP1 from TRIM-25-mediated ubiquitination and proteolysis. LARP1 upregulation subsequently led to DKK4 mRNA stabilisation by competitively interacting with PABPC1 to prevent DKK4 mRNA from B-cell translocation gene 2-dependent deadenylation and degradation, thus facilitating ß-catenin protein expression and nuclear import. CONCLUSION: This study indicates that upregulated protein level of O-GlcNAcylated LARP1 mediated by circCLNS1A promotes the tumorigenesis and progression of HB through LARP1/DKK4/ß-catenin axis. Hence, LARP1 and DKK4 are promising therapeutical target and diagnostic/prognostic plasma biomarker for HB.

SNORD11B-mediated 2'-O-methylation of primary let-7a in colorectal carcinogenesis.

Evidence indicates that small nucleolar RNAs (snoRNAs) participate in tumorigenesis and development and could be promising biomarkers for colorectal cancer (CRC). Here, we examine the profile of snoRNAs in CRC and find that expression of SNORD11B is increased in CRC tumor tissues and cell lines, with a significant positive correlation between SNORD11B expression and that of its host gene NOP58. SNORD11B promotes CRC cell proliferation and invasion and inhibits apoptosis. Mechanistically, SNORD11B promotes the processing and maturation of 18 S ribosomal RNA (rRNA) by mediating 2'-O-methylated (Nm) modification on the G509 site of 18 S rRNA. Intriguingly, SNORD11B mediates Nm modification on the G225 site of MIRLET7A1HG (pri-let-7a) with a canonical motif, resulting in degradation of pri-let-7a, inhibition of DGCR8 binding, reduction in mature tumor suppressor gene let-7a-5p expression, and upregulation of downstream oncogene translation. SNORD11B performs comparably to CEA and CA199 in diagnosing CRC. High expression of SNORD11B is significantly correlated with a more advanced TNM stage and lymph node metastasis, which indicates poor prognosis.

Dual-axis control of magnetic anisotropy in a single crystal Co2MnSi thin film through piezo-voltage-induced strain.

Voltage controlled magnetic anisotropy (VCMA) has been considered as an effective method in traditional magnetic devices with lower power consumption. In this article, we have investigated the dual-axis control of magnetic anisotropy in Co2MnSi/GaAs/PZT hybrid heterostructures through piezo-voltage-induced strain using longitudinal magneto-optical Kerr effect (LMOKE) microscopy. The major modification of in-plane magnetic anisotropy of the Co2MnSi thin film is controlled obviously by the piezo-voltages of the lead zirconate titanate (PZT) piezotransducer, accompanied by the coercivity field and magnetocrystalline anisotropy significantly manipulated. Because in-plane cubic magnetic anisotropy and uniaxial magnetic anisotropy coexist in the Co2MnSi thin film, the initial double easy axes of cubic split to an easiest axis (square loop) and an easier axis (two-step loop). While the stress direction is parallel to the [1-10] easiest axis (sample I), the square loop of the [1-10] direction could transform to a two-step loop under the negative piezo-voltages (compressed state). At the same time, the initial two-step loop of the [110] axis simultaneously changes to a square loop (the easiest axis). Otherwise, we designed and fabricated the sample II in which the PZT stress is parallel to the [110] two-step axis. The phenomenon of VCMA was also obtained along the [110] and [1-10] directions. However, the manipulated results of sample II were in contrast to those of the sample I under the piezo-voltages. Thus, an effective dual-axis regulation of the in-plane magnetization rotation was demonstrated in this work. Such a finding proposes a more optimized method for the magnetic logic gates and memories based on voltage-controlled magnetic anisotropy in the future.

O-GlcNAcylation enhances sensitivity to RSL3-induced ferroptosis via the YAP/TFRC pathway in liver cancer.

Ferroptosis is a form of regulated cell death characterized by iron-dependent accumulation of lipid hydroperoxides to lethal levels. YAP has been reported to play a pivotal role in controlling ferroptotic death, and the expression of YAP is enhanced and stabilized by O-GlcNAcylation. However, whether O-GlcNAcylation can increase the sensitivity of hepatocellular carcinoma (HCC) cells to ferroptosis remains unknown. In the present study, we found that O-GlcNAcylation increased the sensitivity of HCC cells to ferroptosis via YAP. Moreover, YAP increased the iron concentration in HCC cells through transcriptional elevation of TFRC via its O-GlcNAcylation. With YAP knockdown or YAP-T241 mutation, the increased sensitivity to ferroptosis induced by O-GlcNAcylation was abolished. In addition, the xenograft assay confirmed that O-GlcNAcylation increased ferroptosis sensitivity via TFRC in vivo. In summary, we are the first to find that O-GlcNAcylation can increase ferroptosis sensitivity in HCC cells via YAP/TFRC. Our work will provide a new basis for clinical therapeutic strategies for HCC patients.

Design and Synthesis of an Artificial Perpendicular Hard Ferrimagnet with High Thermal and Magnetic Field Stabilities.

It is of great fundamental and practical interest to develop effective means of modulating the magnetic hystereses of magnetic materials and their heterostructures. A notable example is the exchange bias (EB) effect between an antiferromagnet or ferrimagnet and a ferromagnet, which has been widely employed to manipulate magnetic anisotropy in spintronic devices and artificial magnets. Here, we report the design, synthesis and characterization of a synthetic perpendicularly-magnetized ferrimagnet based on [Mn2.9Ga/Co2MnSi]n superlattices, which attains thermal stability above 400 K and a coercive field up to 45 kOe through a mechanism of magnetic compensation. The structure is incorporated into a prototype Heusler alloy and MgO barrier based magnetic tunnel junction, which demonstrates high dynamic range linear field responses and an unusual in-plane EB effect. With increasing temperature, the coercive field reaches beyond 70 kOe at 400 K in this device due to the increasing degree of magnetic moment compensation in the superlattice. The results demonstrate that the compensation mechanism can be utilized to achieve simultaneous thermal robustness and high coercivity in realistic spintronic devices.

MnGa-based fully perpendicular magnetic tunnel junctions with ultrathin Co2MnSi interlayers.

Because tetragonal structured MnGa alloy has intrinsic (not interface induced) giant perpendicular magnetic anisotropy (PMA), ultra-low damping constant and high spin polarization, it is predicted to be a kind of suitable magnetic electrode candidate in the perpendicular magnetic tunnel junction (p-MTJ) for high density spin transfer torque magnetic random access memory (STT-MRAM) applications. However, p-MTJs with both bottom and top MnGa electrodes have not been achieved yet, since high quality perpendicular magnetic MnGa films can hardly be obtained on the MgO barrier due to large lattice mismatch and surface energy difference between them. Here, a MnGa-based fully p-MTJ with the structure of MnGa/Co2MnSi/MgO/Co2MnSi/MnGa is investigated. As a result, the multilayer is with high crystalline quality, and both the top and bottom MnGa electrodes show well PMA. Meanwhile, a distinct tunneling magnetoresistance (TMR) ratio of 65% at 10 K is achieved. Ultrathin Co2MnSi films are used to optimize the interface quality between MnGa and MgO barrier. A strong antiferromagnetic coupling in MnGa/Co2MnSi bilayer is confirmed with the interfacial exchange coupling constant of -5erg/cm2. This work proposes a novel p-MTJ structure for the future STT-MRAM progress.