KHSRP Stabilizes m6A-Modified Transcripts to Activate FAK Signaling and Promote Pancreatic Ductal Adenocarcinoma Progression.

N6-methyladenosine (m6A) is the most prevalent RNA modification and is associated with various biological processes. Proteins that function as readers and writers of m6A modifications have been shown to play critical roles in human malignancies. Here, we identified KH-type splicing regulatory protein (KHSRP) as an m6A binding protein that contributes to the progression of pancreatic ductal adenocarcinoma (PDAC). High KHSRP levels were detected in PDAC and predicted poor patient survival. KHSRP deficiency suppressed PDAC growth and metastasis in vivo. Mechanistically, KHSRP recognized and stabilized FAK pathway mRNAs, including MET, ITGAV and ITGB1, in an m6A-dependent manner, which led to activation of downstream FAK signaling that promoted PDAC progression. Targeting KHSRP with a PROTAC showed promising tumor suppressive effects in mouse models, leading to prolonged survival. Together, these findings indicate that KHSRP mediates FAK pathway activation in an m6A-dependent manner to support PDAC growth and metastasis, highlighting the potential of KHSRP as a therapeutic target in pancreatic cancer.

Acquisition of different transcriptional shear mRNA and biological function of porcine interleukin 18 binding protein in PRRSV infection.

Interleukin-18 binding protein (IL-18BP), a natural regulator molecule of the pro-inflammatory cytokine interleukin-18 (IL-18), plays an important role in regulating the expression of the cellular immunity factor interferon-γ (IFN-γ). In a previous RNA-seq analysis of porcine alveolar macrophages (PAM) infected with the TIM and TJ strains of porcine reproductive and respiratory syndrome virus (PRRSV), we unexpectedly found that the mRNA expression of porcine interleukin 18-binding protein (pIL-18BP) in PAM cells infected with the TJM strain was significantly higher than that infected with the TJ strain. Studies have shown that human interleukin-18 binding protein (hIL-18bp) plays an important role in regulating cellular immunity in the course of the disease. However, there is a research gap on pIL-18BP. At the same time, PRRSV infection in pigs triggers weak cellular immune response problems. To explore the expression and the role of pIL-18BP in the cellular immune response induced by PRRSV, we strived to acquire the pIL-18BP gene from PAM or peripheral blood mononuclear cell (PBMC) with RT-PCR and sequencing. Furthermore, pIL-18BP and pIL-18 were both expressed prokaryotically and eukaryotically. The colocalization and interaction based on recombinant pIL-18BP and pIL-18 on cells were confirmed in vitro. Finally, the expression of pIL-18BP, pIL-18, and pIFN-γ was explored in pigs with different PRRSV infection states to interpret the biological function of pIL-18BP in vivo. The results showed there were five shear mutants of pIL-18BP. The mutant with the longest coding region was selected for subsequent functional validation. First, it was demonstrated that TJM-induced pIL-18BP mRNA expression was higher than that of TJ. A direct interaction between pIL-18BP and pIL-18 was confirmed through fluorescence colocalization, bimolecular fluorescent complimentary (BIFC), and co-immunoprecipitation (CO-IP). pIL-18BP also can regulate pIFN-γ mRNA expression. Finally, the expression of pIL-18BP, pIL-18, and pIFN-γ was explored in different PRRSV infection states. Surprisingly, both mRNA and protein expression of pIL-18 were suppressed. These findings fill the gap in understanding the roles played by pIL-18BP in PRRSV infection and provide a foundation for further research.IMPORTANCEPRRSV-infected pigs elicit a weak cellular immune response and the mechanisms of cellular immune regulation induced by PRRSV have not yet been fully elucidated. In this study, we investigated the role of pIL-18BP in PRRSV-induced immune response referring to the regulation of human IL-18BP to human interferon-gamma (hIFN-γ). This is expected to be used as a method to enhance the cellular immune response induced by the PRRSV vaccine. Here, we mined five transcripts of the pIL-18BP gene and demonstrated that it interacts with pIL-18 and regulates pIFN-γ mRNA expression. Surprisingly, we also found that both mRNA and protein expression of pIL-18 were suppressed under different PRRSV strains of infection status. These results have led to a renewed understanding of the roles of pIL-18BP and pIL-18 in cellular immunity induced by PRRSV infection, which has important implications for the prevention and control of PRRS.

Pt/Al2O3@Ce/ZrO2-S bifunctional catalysts prepared by mechanically milling for selective catalytic oxidation of high-concentration ammonia.

The selective catalytic oxidation (SCO) is an effective method for removing slipped high-concentration ammonia from NH3-fueled engine exhaust gas. Herein a novel bifunctional catalyst was synthesized by mechanically mixing sulfated Ce/ZrO2 (Ce/ZrO2-S) with a small fraction of Pt/Al2O3 (Pt 0.1 wt.%) for SCO of NH3. As expected, the introduction of a small amount of Pt/Al2O3 significantly improved NH3 conversion ability of Ce/ZrO2-S catalysts toward low-temperature direction. When the mass ratio of Pt/Al2O3 to Ce/ZrO2-S was 7.5% (the corresponding mixed catalyst was denoted as P@CZS-7.5), T90 temperature was 312 °C. More importantly, P@CZS-7.5 catalyst exhibited a much better N2 selectivity (> 96%) in a wide temperature range (320 ~ 450 °C). H2-TPR results revealed that the addition of a trace amount of Pt/Al2O3 significantly led to a distinct shift of reduction temperature peak toward low-temperature direction, thereby greatly improved the low-temperature redox performance of mixed catalysts. Furthermore, NH3-TPD and BET results showed that P@CZS-7.5 catalyst exhibited a similar NH3 adsorption capacity to Ce/ZrO2-S catalyst, while the former had a relatively higher specific surface area than the latter. It was considered as a crucial factor for P@CZS-7.5 catalyst maintaining superior N2 selectivity in high-concentration NH3 (5000 ppm) removal processes. In situ DRIFTS results indicated that P@CZS-7.5 catalyst followed the internal selective catalytic reduction (i-SCR) mechanism in NH3-SCO reactions.

Evolution Characterization and Pathogenicity of an NADC34-like PRRSV Isolated from Inner Mongolia, China.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a pathogen that causes severe abortions in sows and high piglet mortality, resulting in huge economic losses to the pig industry worldwide. The emerging and novel PRRSV isolates are clinically and biologically important, as there are likely recombination and pathogenic differences among PRRSV genomes. Furthermore, the NADC34-like strain has become a major epidemic strain in some parts of China, but the characterization and pathogenicity of the latest strain in Inner Mongolia have not been reported in detail. In this study, an NADC34-like strain (CHNMGKL1-2304) from Tongliao City, Inner Mongolia was successfully isolated and characterized, and confirmed the pathogenicity in pigs. The phylogenetic tree showed that this strain belonged to sublineage 1.5 and had high homology with the strain JS2021NADC34. There is no recombination between CHNMGKL1-2304 and any other domestic strains. Animal experiments show that the CHNMGKL1-2304 strain is moderately virulent to piglets, which show persistent fever, weight loss and high morbidity but no mortality. The presence of PRRSV nucleic acids was detected in both blood, tissues, nasal and fecal swabs. In addition, obvious pathological changes and positive signals were observed in lung, lymph node, liver and spleen tissues when subjected to hematoxylin-eosin (HE) staining and immunohistochemistry (IHC). This report can provide a basis for epidemiological investigations and subsequent studies of PRRSV.

QDPR deficiency drives immune suppression in pancreatic cancer.

The relevance of biopterin metabolism in resistance to immune checkpoint blockade (ICB) therapy remains unknown. We demonstrate that the deficiency of quinoid dihydropteridine reductase (QDPR), a critical enzyme regulating biopterin metabolism, causes metabolite dihydrobiopterin (BH2) accumulation and decreases the ratio of tetrahydrobiopterin (BH4) to BH2 in pancreatic ductal adenocarcinomas (PDACs). The reduced BH4/BH2 ratio leads to an increase in reactive oxygen species (ROS) generation and a decrease in the distribution of H3K27me3 at CXCL1 promoter. Consequently, myeloid-derived suppressor cells are recruited to tumor microenvironment via CXCR2 causing resistance to ICB therapy. We discovered that BH4 supplementation is capable to restore the BH4/BH2 ratio, enhance anti-tumor immunity, and overcome ICB resistance in QDPR-deficient PDACs. Tumors with lower QDPR expression show decreased responsiveness to ICB therapy. These findings offer a novel strategy for selecting patient and combining therapies to improve the effectiveness of ICB therapy in PDAC.