Yurong Da

Folate metabolism is a crucial biological process in cell proliferation and exhibits its pro-tumorigenic functions in multiple tumor types. However, its role in pulmonary neuroendocrine carcinomas remains uncertain. Folate metabolism related genes were obtained from previous studies, and the gene expression data and clinical data were collected from GEO database. The expression patterns of folate metabolism related genes were measured across normal and tumor tissues. We subsequently assessed their prognostic role using Kaplan-Meier and univariate Cox regression analysis. The core genes were isolated from 16 prognostic genes through four algorithms. Based on the expression of core genes, patients were divided into two clusters employing consensus clustering algorithm. Furthermore, we evaluated immune infltration level, biological mechanisms, and drug sensitivity. ALDH1L2 was finally identified through qRT-PCR and its pro-tumorigenic function was confirmed via in vitro experiments. The expression patterns of 26 folate metabolism related genes were evaluated between normal lung tissues and PNEC tumor tissues, and 20 of them exhibited differential expression. All of folate metabolism related genes were related to the prognosis of PNECS and 16 genes were identified as prognostic genes. Using SVM-RFE, RF, Xgboost and LASSO algorithm, three core genes were isolated from 16 prognostic genes. Based on the expression patterns of core genes, PNECs patients were divided into two clusters through consensus clustering algorithm. Cluster 1 was characterized by the worse survival, higher immune infiltration level, and sensitivity to chemotherapy. Compared with the HBEC cells, ALDH1L2 was notably overexpressed in NCI-H446 cells (SCLC cell line). ALDH1L2 knockdown significantly repressed the proliferation and migration capacity of tumor cells and increased the cell proportion in S phase. Our results indicated that folate metabolism gene signature is a reliable biomarker for PNECs. Classification based on this signature could be utilized to guide the treatment of PNECs patients and improve its prognosis.

In multiple sclerosis (MS), the imbalance between T helper (Th)-17 cells and regulatory T (Treg) cells are critical in autoimmune central nervous system (CNS) inflammation and demyelination. Experi...

Background: Pyroptosis, as an inflammatory form of cell death, is involved in many physiological and pathological processes. Neuroblastoma is the most common extra-cranial solid tumor in children. In this study, the relationship between pyroptosis and tumor microenvironment in neuroblastoma was systematically studied. Methods: We integrated four datasets of neuroblastomas. Through robust clustering of the mRNA expression profiles of 24 pyroptosis-related genes, a total of three pyroptosis patterns were identified. We then constructed a novel scoring method named as pyroscore to quantify the level of pyroptosis in neuroblastoma. Multi-omics data and single-cell RNA sequencing were used to accurately and comprehensively evaluate the effectiveness of pyroscore. Clinical data sets were used to evaluate the use of pyroscore to predict the responsiveness of immune checkpoint treatment. Results: High pyroscore was associated with good prognosis, immune activation, and increased response to checkpoint blockade immunotherapy. Multivariate Cox analysis revealed that the pyroscore was an independent prognostic biomarker and could increase the accuracy of clinical prediction models. Etoposide, a drug picked up by our analysis, could increase the sensitivity of neuroblastoma cells to pyroptosis. External verification using four cohorts of patients who had received immunotherapy showed that high pyroscore was significantly associated with immunotherapy treatment benefit. Conclusions: Taken together, this study revealed that pyroptosis-related gene network could quantify the response of neuroblastoma to immune checkpoint blockade therapy and prognosis, and it may be helpful for clinical practitioners to choose treatment strategies for neuroblastoma patients.

Pin1 is the only known peptidyl-prolyl cis-trans isomerase (PPIase) that can specifically recognize and isomerize the phosphorylated Serine/Threonine-Proline (pSer/Thr-Pro) motif, change the conformation of proteins through protein phosphorylation, thus regulate various cellular processes in the body. Pin1 plays an important role in cancer, Alzheimer’s disease, and autoimmune diseases. However, the specific mechanism of Pin1 regulation in LPS-induced septic shock is unclear. Here, we found that lack of Pin1 reduced shock mortality and organ damage in mice, and NLRP3 inflammasome activation also was reduced in this process. We further confirmed that Pin1 can affect the expression of NLRP3, ASC, Caspase1, and this process can be regulated through the p38 MAPK pathway. We analyzed that p38 MAPK signaling pathway was highly expressed in septic shock and showed a positive correlation with Pin1 in the Gene Expression Omnibus database. We found that Pin1 could affect the phosphorylation of p38 MAPK, have no obvious difference in extracellular signal-regulated kinases (ERK) and Jun-amino-terminal kinase (JNK) signaling. We further found that Pin1 and p-p38 MAPK interacted, but not directly. In addition, Pin1 deficiency inhibited the cleavage of gasdermin D (GSDMD) and promoted the death of macrophages with LPS treatment, and reduced secretion of inflammatory cytokines including IL-1β and IL-18. In general, our results suggest that Pin1 regulates the NLRP3 inflammasome activation by p38 MAPK signaling pathway in macrophages. Thus, Pin1 may be a potential target for the treatment of inflammatory diseases such as septic shock.

MiR-21 is aberrantly expressed, and plays a role in various types of tumors and many other diseases. However, the mechanism of miR-21 in LPS-induced septic shock is still unclear. In this study, we investigated the mechanism of miR-21 in LPS-induced pyroptosis and septic shock. Here, we show that miR-21 deficiency inhibited NLRP3, ASC, and caspase-1 expression, as well as inflammasome activation in myeloid cells from both mice and humans. We found that the NF-κB pathway was regulated by miR-21, and that A20 was a direct target of miR-21. Furthermore, miR-21 deficiency inhibited the ASC pyroptosome, which restrained caspase-1 activation and GSDMD cleavage, thereby preventing LPS-induced pyroptosis and septic shock. miR-21 deficiency resulted in an increase in A20, which led to decreased IL-1β production and caspase-1 activation. Caspase-1-mediated GSDMD cleavage was consequently decreased, which prevented pyroptosis in LPS-induced sepsis in mice. Our results demonstrate that miR-21 is a critical positive regulator of the NF-κB pathway and NLRP3 inflammasomes in pyroptosis and septic shock via A20. In addition, by analyzing published miRNA expression profiles in the Gene Expression Omnibus database, we found that the miR-21 levels in peripheral blood from patients with septic shock were elevated. Thus, miR-21 may serve as a potential treatment target in patients with septic shock.

Muscle redox disturbances and oxidative stress have emerged as a common pathogenetic mechanism and potential therapeutic intervention in some muscle diseases. Parthenolide (PTL), a sesquiterpene lactone found in large amounts in the leaves of feverfew, possesses anti‐inflammatory, anti‐migraine, and anticancer properties. Although PTL was reported to alleviate cancer cachexia and improve skeletal muscle characteristics in a cancer cachexia model, its actions on oxidative stress‐induced damage in C2C12 myoblasts have not been reported and the regulatory mechanisms have not yet been defined. In our study, PTL attenuated H₂O₂‐induced growth inhibition and morphological changes. Furthermore, PTL exhibited scavenging activity against reactive oxygen species and protected C2C12 cells from apoptosis in response to H₂O₂. Meanwhile, PTL suppressed collapse of the mitochondrial membrane potential, thereby contributing to normalizing H₂O₂‐induced autophagy flux and mitophagy, correlating with inhibiting degradation of mitochondrial marker protein TIM23, the increase in LC3‐II expression and the reduction of mitochondria DNA. Besides its protective effect on mitochondria, PTL also prevented H₂O₂‐induced lysosomes damage in C2C12 cells. In addition, the phosphorylation of p53, cathepsin B, and Bax/Bcl‐2 protein levels, and the translocation of Bax from the cytosol to mitochondria induced by H₂O₂ in C2C12 cells was significantly reduced by PTL. In conclusion, PTL modulates oxidative stress‐induced mitophagy and protects C2C12 myoblasts against apoptosis, suggesting a potential protective effect against oxidative stress‐associated skeletal muscle diseases.

Background This study compared tumor‐related signaling pathways with known compounds to determine potential agents for lung adenocarcinoma (LUAD) treatment. Methods Kyoto Encyclopedia of Genes and Genomes signaling pathway analyses were performed based on LUAD differentially expressed genes from The Cancer Genome Atlas (TCGA) project and genotype‐tissue expression controls. These results were compared to various known compounds using the Connectivity Mapping dataset. The clinical significance of the hub genes identified by overlapping pathway enrichment analysis was further investigated using data mining from multiple sources. A drug‐pathway network for LUAD was constructed, and molecular docking was carried out. Results After the integration of 57 LUAD‐related pathways and 35 pathways affected by small molecules, five overlapping pathways were revealed. Among these five pathways, the p53 signaling pathway was the most significant, with CCNB1, CCNB2, CDK1, CDKN2A, and CHEK1 being identified as hub genes. The p53 signaling pathway is implicated as a risk factor for LUAD tumorigenesis and survival. A total of 88 molecules significantly inhibiting the five LUAD‐related oncogenic pathways were involved in the LUAD drug‐pathway network. Daunorubicin, mycophenolic acid, and pyrvinium could potentially target the hub gene CHEK1 directly. Conclusion Our study highlights the critical pathways that should be targeted in the search for potential LUAD treatments, most importantly, the p53 signaling pathway. Some compounds, such as ciclopirox and AG‐028671, may have potential roles for LUAD treatment but require further experimental verification.