miR-193a Directly Targets PSEN1 and Inhibits Gastric Cancer Cell Growth, the Activation of PI3K/Akt Signaling Pathway, and the Epithelial-to-Mesenchymal Transition

A novel tumor immunotherapy-related signature for risk stratification, prognosis prediction, and immune status in hepatocellular carcinoma

Immunotherapy as a strategy to deal with cancer is increasingly being used clinically, especially in hepatocellular carcinoma (HCC). We aim to create an immunotherapy-related signature that can play a role in predicting HCC patients' survival and therapeutic outcomes. Immunotherapy-related genes were discovered first. Clinical information and gene expression data were extracted from GSE140901. By a series of bioinformatics methods to analyze, overlapping genes were used to build an immunotherapy-related signature that could contribute to predict both the prognosis of people with hepatocellular carcinoma and responder to immune checkpoint blockade therapy of them in TCGA database. Differences of the two groups in immune cell subpopulations were then compared. Furthermore, A nomogram was constructed, based on the immunotherapy-related signature and clinicopathological features, and proved to be highly predictive. Finally, immunohistochemistry assays were performed in HCC tissue and normal tissue adjacent tumors to verify the differences of the four genes expression. As a result of this study, a prognostic protein profile associated with immunotherapy had been created, which could be applied to predict patients' response to immunotherapy and may provide a new perspective as clinicians focus on non-apoptotic treatment for patients with HCC.

Targeting lncRNA NEAT1 Hampers Alzheimer's Disease Progression

Long noncoding RNA nuclear enriched abundant transcript 1 (lnc-NEAT1) is closely implicated in neurological diseases, while its implication in Alzheimer's disease (AD) is rarely reported. This study aimed to investigate the effect of lnc-NEAT1 knockdown on neuron injury, inflammation, and oxidative stress in AD, as well as its interaction with downstream targets and pathways. APPswe/PS1dE9 transgenic mice were injected with negative control or lnc-NEAT1 interference lentivirus. Besides, AD cellular model was constructed by amyloid β treatment in mice primary neuron cells; then, knockdown of lnc-NEAT1 and microRNA-193a was performed alone or in combination. In vivo experiments revealed that Lnc-NEAT1 knockdown improved cognition in AD mice reflected by Morrison water maze and Y-maze assays. Besides, lnc-NEAT1 knockdown reduced injury and apoptosis, decreased inflammatory cytokine levels, repressed oxidative stress level, and activated adenosine cyclophosphate response element-binding protein (CREB)/brain-derived neurotrophic factor (BDNF) and nuclear factor erythroid 2-related factor 2 (NRF2)/nicotinamide adenine dinucleotide phosphate dehydrogenase 1 (NQO1) pathways in hippocampi of AD mice. Notably, lnc-NEAT1 down-regulated microRNA-193a both in vitro and in vivo and acted as a decoy of microRNA-193a. In vitro experiments showed that lnc-NEAT1 knockdown decreased apoptosis and oxidative stress, improved cell viability, also activated CREB/BDNF and NRF2/NQO1 pathways in AD cellular model. Meanwhile, microRNA-193a knockdown showed the opposite effects, which also attenuated lnc-NEAT1 knockdown-mediated reduction in injury, oxidative stress, and CREB/BDNF and NRF2/NQO1 pathways of AD cellular model. In conclusion, lnc-NEAT1 knockdown reduces neuron injury, inflammation, and oxidative stress through activating microRNA-193a mediated CREB/BDNF and NRF2/NQO1 pathways in AD.

Presenilin-1 (PSEN1) Mutations: Clinical Phenotypes beyond Alzheimer's Disease

Presenilin 1 (PSEN1) is a part of the gamma secretase complex with several interacting substrates, including amyloid precursor protein (APP), Notch, adhesion proteins and beta catenin. PSEN1 has been extensively studied in neurodegeneration, and more than 300 PSEN1 mutations have been discovered to date. In addition to the classical early onset Alzheimer's disease (EOAD) phenotypes, PSEN1 mutations were discovered in several atypical AD or non-AD phenotypes, such as frontotemporal dementia (FTD), Parkinson's disease (PD), dementia with Lewy bodies (DLB) or spastic paraparesis (SP). For example, Leu113Pro, Leu226Phe, Met233Leu and an Arg352 duplication were discovered in patients with FTD, while Pro436Gln, Arg278Gln and Pro284Leu mutations were also reported in patients with motor dysfunctions. Interestingly, PSEN1 mutations may also impact non-neurodegenerative phenotypes, including PSEN1 Pro242fs, which could cause acne inversa, while Asp333Gly was reported in a family with dilated cardiomyopathy. The phenotypic diversity suggests that PSEN1 may be responsible for atypical disease phenotypes or types of disease other than AD. Taken together, neurodegenerative diseases such as AD, PD, DLB and FTD may share several common hallmarks (cognitive and motor impairment, associated with abnormal protein aggregates). These findings suggested that PSEN1 may interact with risk modifiers, which may result in alternative disease phenotypes such as DLB or FTD phenotypes, or through less-dominant amyloid pathways. Next-generation sequencing and/or biomarker analysis may be essential in clearly differentiating the possible disease phenotypes and pathways associated with non-AD phenotypes.

PSEN1 is associated with colon cancer development via potential influences on PD-L1 nuclear translocation and tumor-immune interactions

Presenilin 1 (PSEN1), as a catalytical core of the γ-secretase complex, plays multiple actions through mediating transmembrane domain shedding of the substrates. Unlike extensive studies performed on investigating the functions of γ-secretase substrates or the effects of γ-secretase inhibitors, our findings uncover a potential action of PSEN1 on PD-L1 alternative truncation and nuclear translocation, broadening our understanding on how the γ-secretase contributes to colon cancer development as well as suggesting a potential strategy to improve the efficacy of PD-1/PD-L1 blockade. Immunohistochemical data showed loss of PD-L1 protein expression in all the primary colon adenocarcioma (COAD) cases in the HPA collection, while PSEN1 was scored to be highly expressed, indicating their converse expression patterns (p<0.001). Meanwhile a strongly positive gene correlation was explored by TIMER2 and GEPIA (p<0.001). Up-regulated PSEN1 expression in COAD might facilitate liberating a C-terminal PD-L1 truncation via proteolytic processing. Then following an established regulatory pathway of PD-L1 nuclear translocation, we found that PSEN1 showed significant correlations with multiple components in HDAC2-mediated deacetylation, clathrin-dependent endocytosis, vimentin-associated nucleocytoplasmic shuttling and importin family-mediated nuclear import. Moreover, connections of PSEN1 to the immune response genes transactivated by nuclear PD-L1 were tested. Additionally, contributions of PSEN1 to the tumor invasiveness (p<0.05) and the tumor infiltrating cell enrichments (p<0.001) were investigated by cBioportal and the ESTIMATE algorithm. Levels of PSEN1 were negatively correlated with infiltrating CD8+ T (p<0.05) and CD4+ T helper (Th) 1 cells (p<0.001), while positively correlated with regulatory T cells (Tregs) (p<0.001) and cancer associated fibroblasts (CAFs) (p<0.001). It also displayed significant associations with diverse immune metagenes characteristic of T cell exhaustion, Tregs and CAFs, indicating possible actions in immune escape. Despite still a preliminary stage of this study, we anticipate to deciphering a novel function of PSEN1, and supporting more researchers toward the elucidations of the mechanisms linking the γ-secretase to cancers, which has yet to be fully addressed.

MiR-654-3p Constrains Proliferation, Invasion, and Migration of Sinonasal Squamous Cell Carcinoma via CREB1/PSEN1 Regulatory Axis

Background: MiR-654-3p can repress malignant progression of cancer cells, whereas no relative reports were about its modulatory mechanism in sinonasal squamous cell carcinoma (SNSCC). This research committed to approaching modulatory effect of miR-654-3p on SNSCC cells. Methods: Bioinformatics methods were utilized for analyzing interaction of miR-654-3p/cAMP-responsive element binding protein 1 (CREB1)/presenilin-1 (PSEN1). Expression levels of miR-654-3p, CREB1, and PSEN1 mRNA were assessed by quantitative real-time polymerase chain reaction. Western blot was completed for level assessment of CREB1, PSEN1, and epithelial-mesenchymal transition-related proteins. The targeted relationship between miR-654-3p and CREB1, or CREB1 and PSEN1 was authenticated via dual-luciferase assay and ChIP assay. A trail of experiments in vitro was used for detection of the effects of miR-654-3p/CREB1/PSEN1 axis on malignant progression of SNSCC cells. Results: CREB1 as the downstream target mRNA of miR-654-3p could activate transcription of its downstream target gene PSEN1. Besides, miR-654-3p could target CREB1 to repress PSEN1 expression, thus restraining proliferation, migration, invasion, epithelial-mesenchymal transition, and hastening apoptosis of SNSCC cells. Conclusion: MiR-654-3p as an antitumor gene targeted CREB1 to hamper malignant progression of SNSCC through miR-654-3p/CREB1/PSEN1 axis.