Notch Pathway Research Articles

Contemporary directions in the therapy of sensory hearing loss

<b>Introduction:</b> More than 5% of the world’s population experience hearing impairment. The most common form is presbycusis (age-related hearing loss; ARHL). It affects almost one in three people over the age of 65. The hair cells of the cochlea play an important role in the process of sound registration. Genetic mutations, aging and environmental factors can cause damage that contributes to the hearing loss.<b>Methods and results:</b> The currently explored research directions include drug treatments, gene therapies, and stem cell therapies. To date, no significant differences in the therapeutic effect depending on the route of corticosteroid administration have been demonstrated in patients with moderate to severe hearing loss. New dexamethasone-containing hydrogel formulations, as well as lipid formulations, thermosensitive polymers, and nanoparticles, have been developed to achieve high drug concentrations in the inner ear structures. Otoprotective effects of antioxidants or substances that modify the toxic effects of e.g. cisplatin, are also being studied. Attempts at auditory cells’ regeneration seem promising in hearing loss research. Substances that regulate the central mechanisms of the Notch and Wnt pathways are being explored to this end. The genetic determinants of presbycusis suggest that interference at the level of specific genes may be a promising option for the treatment of this condition. With the CRISPR/Cas9 technology, the functions of inner ear genes can be effectively studied by disrupting normal gene alleles. The CRISPR/Cas9 complexes developed to target specific genes are delivered using cationic lipids, proteins, and viral vectors. They are then transported through the round window membrane by diffusion, without the need to surgically disrupt the inner ear. The potential of using antisense oligonucleotides to treat hereditary deafness caused by hair cell degeneration has also been established. Another research direction is related to stem cells being used for the development of in vitro 3D models of the human inner ear. Studies are also pursued to identify the mechanisms underlying the formation of cochlear organoids from pluripotent cells as well as determine the critical time points and events for cochlear sensory epithelial development and targeted hair cell differentiation.<b>Conclusions:</b> In summary, significant progress has been made over the past decade in the search for novel therapies for sensory hearing loss. This line of research remains an ambitious and important area for further exploration.

Application of Monoclonal Antibodies against Naturally Occurring Bioactive Ingredients.

Monoclonal antibodies (Mabs) are widely used in a variety of fields, including protein identification, life sciences, medicine, and natural product chemistry. This review focuses on Mabs against naturally occurring active compounds. The preparation of Mabs against various active compounds began in the 1980s, and now there are fewer than 50 types. Eastern blotting, which was developed as an antibody staining method for low-molecular-weight compounds, is useful for its ability to visually represent specific components. In this method, a mixture of lower-molecular-weight compounds, particularly glycosides, are separated by thin-layer chromatography (TLC). The compounds are then transferred to a membrane by heating, followed by treatment with potassium periodate (KIO4) to open the sugar moiety of the glycoside on the membrane to form an aldehyde group. Proteins are then added to form Schiff base bonds to enable adsorption on the membrane. A Mab is bound to the glycoside moiety on the membrane and reacts with a secondary antibody to produce color. Double Eastern blotting, which enables the simultaneous coloration of two glycosides, can be used to evaluate quality and estimate pharmacological effects. An example of staining by Eastern blotting and a component search based on the results will also be presented. A Mab-associated affinity column is a method for isolating antigen molecules in a single step. However, the usefulness of the wash fractions that are not bound to the affinity column is unknown. Therefore, we designated the wash fraction the "knockout extract". Comparing the nitric oxide (NO) production of a glycyrrhizin (GL)-knockout extract of licorice with a licorice extract revealed that the licorice extract is stronger. Therefore, the addition of GL to the GL-knockout extract of licorice increased NO production. This indicates that GL has synergic activity with the knockout extract. The GL-knockout extract of licorice inhibited high-glucose-induced epithelial-mesenchymal transition in NRK-52E cells, primarily by suppressing the Notch2 pathway. The real active constituent in licorice may be constituents other than GL, which is the causative agent of pseudohyperaldosteronism. This suggests that a GL-knockout extract of licorice may be useful for the treatment of diabetic nephritis.

Notch signaling suppresses neuroendocrine differentiation and alters the immune microenvironment in advanced prostate cancer.

Notch signaling can have either an oncogenic or tumor suppressive function in cancer depending on the cancer type and cellular context. While Notch can be oncogenic in early prostate cancer, we identified significant downregulation of the Notch pathway during prostate cancer progression from adenocarcinoma to neuroendocrine prostate cancer where it functions as a tumor suppressor. Activation of Notch in neuroendocrine and Rb1/Trp53-deficient prostate cancer models led to phenotypic conversion towards a more indolent non-neuroendocrine state with glandular features and expression of luminal lineage markers. This was accompanied by up-regulation of MHC and type I interferon and immune cell infiltration. Overall, these data support Notch signaling as a suppressor of neuroendocrine differentiation in advanced prostate cancer and provides insights into how Notch signaling influences lineage plasticity and the tumor microenvironment.

The Role of NOTCH Pathway Genes in the Inherited Susceptibility to Aortic Stenosis.

The NOTCH-signaling pathway is responsible for intercellular interactions and cell fate commitment. Recently, NOTCH pathway genes were demonstrated to play an important role in aortic valve development, leading to an increased calcified aortic valve disease (CAVD) later in life. Here, we further investigate the association between genetic variants in the NOTCH pathway genes and aortic stenosis in a case-control study of 90 CAVD cases and 4723 controls using target panel sequencing of full-length 20 genes from a NOTCH-related pathway (DVL2, DTX2, MFNG, NUMBL, LFNG, DVL1, DTX4, APH1A, DTX1, APH1B, NOTCH1, ADAM17, DVL3, NCSTN, DTX3L, ILK, RFNG, DTX3, NOTCH4, PSENEN). We identified a common intronic variant in NOTCH1, protecting against CAVD development (rs3812603), as well as several rare and unique new variants in NOTCH-pathway genes (DTX4, NOTCH1, DTX1, DVL2, NOTCH1, DTX3L, DVL3), with a prominent effect of the protein structure and function.

The Role of Notch1 Pathway Regulating CD4+CD25+Foxp3+ T Cells in Renovascular Hypertension

Abstract OBJECTIVE To explore the role and mechanism of the Notch1 pathway in regulating CD4+CD25+Foxp3+ Treg cells in renal vascular hypertension (RVH). METHODS According to the diagnostic criteria of RVH in the 8th edition of Internal Medicine, 220 patients treated in the Department of Nephrology of Sichuan Provincial People’s Hospital from January 2019 to January 2022 were enrolled in RVH group, and 220 patients with essential hypertension (EH) in the same period were selected as EH group; another 220 healthy examinees were selected as control group (NC). The proportion of CD4+CD25+ Treg cells in peripheral blood mononuclear cells (PBMCs) and the expression levels of interleukin-10 (IL-10), transforming growth factor-β (TGF-β), and cell proliferation nuclear antigen-67 (Ki-67) in PBMC of the 3 groups were compared by real-time fluorescence quantitative PCR and western blotting; the relative expression levels of Notch1 receptor and ligand mRNA in PBMC of the 3 groups were compared by real-time fluorescence quantitative PCR; the expression of downstream proteins Hes1 and Hes5 of Notch1 signaling pathway, the proportion of CD4+CD25+Foxp3+ Treg cells, and the effect on TGF-β expression were compared by western blotting after adding Notch1 signaling pathway inhibitor (DAPT). Real-time quantitative PCR and western PCR were used. The proportion of CD4+CD25+ Treg cells in PBMCs and the expression levels of IL-10, TGF-β, and cell proliferating nuclear antigen-67 (Ki-67) in PBMC were compared between the 2 groups. Real-time quantitative PCR was used to compare the mRNA expression levels of the Notch1 receptor and ligand in PBMC between the 2 groups. RESULTS Flow cytometry results showed that compared with the NC group, the RVH group had a significantly lower proportion of CD4+CD25+Foxp3+ Treg cells, TGF-β and Ki-67 expression levels, and higher IL-10 expression levels, with significant differences (P < 0.001). Compared with the RVH group, the EH group had a significantly higher proportion of CD4+CD25+Foxp3+ Treg cells, TGF-β and Ki-67 expression levels, and lower IL-10 expression levels, with significant differences (P < 0.001). Real-time quantitative PCR results showed that the RVH group also had significantly higher relative expression levels of Notch receptor Notch1 mRNA, Notch ligand DLL1, DLL4, Jagged1, and Jagged2 mRNA in PBMC than the NC group and EH group, with significant differences (P < 0.001). Western blot results showed that after adding Notch1 signaling pathway inhibitor (DAPT), Hes1 and Hes5 expression in peripheral CD4+CD25+Foxp3+ Treg cells of patients decreased significantly (P < 0.001), while CD4+CD25+Foxp3+ Treg proportion and TGF-β expression level increased significantly (P < 0.001). CONCLUSIONS The Notch1 signaling pathway plays an immunoregulatory role in RVH regulated by CD4+CD25+Foxp3+ Treg cells. Regulation of the Notch1 signaling pathway can significantly promote the proliferation of CD4+CD25+Foxp3+ Treg cells and the ability to secrete anti-inflammatory factors.

Comprehensive analysis of transcription factors involved in odontoblast differentiation mechanism.

Primary cultured odontoblasts rapidly lose their tissue-specific phenotype. To identify transcription factors (TF) that are important for the maintenance of the odontoblast phenotype, primary cultures of C57BL/6J mouse dental mesenchymal cells (DMC) were isolated, and expression of TF and odontoblast marker genes in cells immediately after isolation and 2days after culture were comprehensively evaluated and compared using RNA-sequencing (RNA-seq). The expression of odontoblast markers in mouse dental mesenchymal cells decreased rapidly after isolation. In addition, the expression of Hedgehog-related, Notch-related, and immediate- early gene (IEG)-related transcription factors significantly decreased. Forced expression of these genes in lentiviral vectors, together with fibroblast growth factor 4 (FGF4), fibroblast growth factor 9 (FGF9), and the Wnt pathway activator CHIR99021, significantly induced the expression of odontogenic marker genes. These results indicate, for the first time, that Notch signaling and early genes may be important for maintaining odontoblast cultures. Furthermore, simultaneous stimulation of FGF, Wnt, Hedgehog, Notch pathways, and IEG transcription factors cooperatively promoted the maintenance of the odontoblast phenotype. These results suggest that the Hedgehog and Notch signaling pathways may play an important role in maintaining odontoblast phenotypes, in addition to FGF and Wnt signaling.

The potential therapeutic value of the natural plant compounds matrine and oxymatrine in cardiovascular diseases.

Matrine (MT) and Oxymatrine (OMT) are two natural alkaloids derived from plants. These bioactive compounds are notable for their diverse pharmacological effects and have been extensively studied and recognized in the treatment of cardiovascular diseases in recent years. The cardioprotective effects of MT and OMT involve multiple aspects, primarily including antioxidative stress, anti-inflammatory actions, anti-atherosclerosis, restoration of vascular function, and inhibition of cardiac remodeling and failure. Clinical pharmacology research has identified numerous novel molecular mechanisms of OMT and MT, such as JAK/STAT, Nrf2/HO-1, PI3 K/AKT, TGF-β1/Smad, and Notch pathways, providing new evidence supporting their promising therapeutic potential against cardiovascular diseases. Thus, this review aims to investigate the potential applications of MT and OMT in treating cardiovascular diseases, encompassing their mechanisms, efficacy, and safety, confirming their promise as lead compounds in anti-cardiovascular disease drug development.

The cellular Notch1 protein promotes KSHV reactivation in an Rta-dependent manner.

Kaposi's sarcoma-associated herpesvirus (KSHV) manipulates the host cell oncogenic Notch signaling pathway for viral reactivation from latency and cell pathogenesis. KSHV reactivation requires that the viral protein Rta functionally interacts with RBP-Jk, the DNA-binding component of the Notch pathway, and with promoter DNA to drive transcription of productive cycle genes. We show that the Notch pathway is constitutively active during KSHV reactivation and is essential for robust production of infectious virus progeny. Inhibiting Notch during reactivation reduces the expression of specific viral genes yet does not affect the growth of the host cells. Although Notch cannot reactivate KSHV alone, the requisite expression of Rta reveals a previously unappreciated role for Notch in reactivation. We propose that activated Notch cooperates with Rta in a promoter-specific manner that is partially programmed by Rta's ability to redistribute RBP-Jk DNA binding to the virus during reactivation.

Interaction of the transforming growth factor-β and Notch signaling pathways in the regulation of granulosa cell proliferation.

The Notch and transforming growth factor (TGF)-β signalling pathways play an important role in granulosa cell proliferation. However, the mechanisms underlying the cross-talk between these two signalling pathways are unknown. Herein we demonstrated a functional synergism between Notch and TGF-β signalling in the regulation of preantral granulosa cell (PAGC) proliferation. Activation of TGF-β signalling increased hairy/enhancer-of-split related with YRPW motif 2 gene (Hey2) expression (one of the target genes of the Notch pathway) in PAGCs, and suppression of TGF-β signalling by Smad3 knockdown reduced Hey2 expression. Inhibition of the proliferation of PAGCs by N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butylester (DAPT), an inhibitor of Notch signalling, was rescued by both the addition of ActA and overexpression of Smad3, indicating an interaction between the TGF-β and Notch signalling pathways. Co-immunoprecipitation (CoIP) and chromatin immunoprecipitation (ChIP) assays were performed to identify the point of interaction between the two signalling pathways. CoIP showed direct protein-protein interaction between Smad3 and Notch2 intracellular domain (NICD2), whereas ChIP showed that Smad3 could be recruited to the promoter regions of Notch target genes as a transcription factor. Therefore, the findings of the present study support the idea that nuclear Smad3 protein can integrate with NICD2 to form a complex that acts as a transcription factor to bind specific DNA motifs in Notch target genes, such as Hey1 and Hey2, and thus participates in the transcriptional regulation of Notch target genes, as well as regulation of the proliferation of PAGCs.

Single-cell sequencing unveils the impact of aging on the progenitor cell diversity in the telencephalon of the female killifish N. furzeri.

The African turquoise killifish (Nothobranchius furzeri) combines a short lifespan with spontaneous age-associated loss of neuro-regenerative capacity, an intriguing trait atypical for a teleost. The impact of aging on the cellular composition of the adult stem cell niches, leading to this dramatic decline in the postnatal neuro- and gliogenesis, remains elusive. Single-cell RNA sequencing of the telencephalon of young adult female killifish of the short-lived GRZ-AD strain unveiled progenitors of glial and non-glial nature, different excitatory and inhibitory neuron subtypes, as well as non-neural cell types. Sub-clustering of the progenitors identified four radial glia (RG) cell types, two non-glial progenitor (NGP) and four intermediate (intercell) cell states. Two astroglia-like, one ependymal, and one neuroepithelial-like (NE) RG subtype were found at different locations in the forebrain in line with their role, while proliferative, active NGPs were spread throughout. Lineage inference pointed to NE-RG and NGPs as start and intercessor populations for glio- and neurogenesis. Upon aging, single-cell RNA sequencing revealed major perturbations in the proportions of the astroglia and intercell states, and in the molecular signatures of specific subtypes, including altered MAPK, mTOR, Notch, and Wnt pathways. This cell catalog of the young regeneration-competent killifish telencephalon, combined with the evidence for aging-related transcriptomic changes, presents a useful resourceto understand the molecular basis of age-dependent neuroplasticity. This data is also available through an online database (killifishbrain_scseq).

MFAP2 induces epithelial-mesenchymal transformation of osteosarcoma cells by activating the Notch1 pathway.

Osteosarcoma (OS) is a malignancy originating from mesenchymal tissue. Microfibril-associated protein 2 (MFAP2) plays a crucial role in cancer, notably promoting epithelial-mesenchymal transition (EMT). However, its involvement in OS remains unexplored. MFAP2 was silenced in U2OS cells using shRNA targeting MFAP2 (sh-MFAP2) and validated by quantitative real-time polymerase chain reaction (qRT-PCR). We extracted gene chip data of MFAP2 from multiple databases (GSE28424, GSE42572, and GSE126209). Correlation analyses between MFAP2 and the Notch1 pathway identified through the gene set variation analysis (GSVA) enrichment analysis were conducted using the Pearson correlation method. Cellular behaviors (viability, migration, and invasion) were assessed via the Cell Counting Kit-8 (CCK-8), wound healing, and Transwell assays. EMT markers (N-cadherin, vimentin, and β-catenin) and Notch1 levels were examined by western blotting and qRT-PCR. Cell morphology was observed microscopically to evaluate EMT. Finally, the role of MFAP2 in OS was validated through a xenograft tumor model. OS cell lines exhibited higher MFAP2 mRNA expression than normal osteoblasts. MFAP2 knockdown in U2OS cells significantly reduced viability, migration, and invasion, along with downregulation of N-cadherin and vimentin, as well as upregulation of β-catenin. MFAP2 significantly correlated with the Notch1 pathway in OS and its knockdown inhibited Notch1 protein expression. Furthermore, Notch1 activation reversed the inhibitory effects of MFAP2 knockdown on the malignant characteristic of U2OS cells. Additionally, MFAP2 knockdown inhibited tumor growth, expression levels of EMT markers, and Notch1 expression in OS tumor tissues. Our study revealed that MFAP2 was an upstream regulator of the Notch1 signaling pathway to promote EMT in OS. These findings suggested MFAP2 as a potential OS therapy target.

Enhanced radiation sensitivity, decreased DNA damage repair, and differentiation defects in airway stem cells derived from patients with chronic obstructive pulmonary disease.

Radiation therapy (RT) is a common treatment for lung cancer. Still, it can lead to irreversible loss of pulmonary function and a significant reduction in quality of life for one-third of patients. Preexisting comorbidities, such as chronic obstructive pulmonary disease (COPD), are frequent in patients with lung cancer and further increase the risk of complications. Because lung stem cells are crucial for the regeneration of lung tissue following injury, we hypothesized that airway stem cells from patients with COPD with lung cancer might contribute to increased radiation sensitivity. We used the air-liquid interface model, a three-dimensional (3D) culture system, to compare the radiation response of primary human airway stem cells from healthy and patients with COPD. We found that COPD-derived airway stem cells, compared to healthy airway stem cell cultures, exhibited disproportionate pathological mucociliary differentiation, aberrant cell cycle checkpoints, residual DNA damage, reduced survival of stem cells and self-renewal, and terminally differentiated cells post-irradiation, which could be reversed by blocking the Notch pathway using small-molecule γ-secretase inhibitors. Our findings shed light on the mechanisms underlying the increased radiation sensitivity of COPD and suggest that airway stem cells reflect part of the pathological remodeling seen in lung tissue from patients with lung cancer receiving thoracic RT.

Insights into the regulation of hearing regeneration

Our perception of sound is mediated by sound-sensitive hair cells in the inner ear, located in a specialized neuro-epithelium that transmits information to the auditory cortex via the auditory pathway. A major cause of hearing loss is damage to and the death of these sensory hair cells. In humans, hair cells are only generated during embryonic development and cannot be replaced if damaged due to aging, excessive noise, ototoxic drugs, or illness. Much research is currently being invested worldwide in identifying methods to improve the ability to regenerate hair cells and circumvent their age-dependent limitations. Compared to numerous studies focused on gene therapy to restore deafness caused by a specific mutation before the onset of hair cell damage, research on auditory epigenetics is relatively recent. Although research indicates that epigenetic alterations play a crucial role in the differentiation, development, and regeneration of auditory hair cells, a dearth of comprehensive knowledge still exists regarding the specific role played by epigenetic modifications in the auditory system, with a particular emphasis on their potential correlation with the function and development of the auditory system. In addition, these modifications have been linked to the regeneration of hair cells caused by using pharmaceutical inhibitors (e.g., inhibition of the Notch pathway) and genetic (e.g., induced Atoh1 expression) treatments, which can lead to regenerating hair cells and restoring hearing. Recent developments in targetable epigenome-editing tools, such as CRISPR, and direct reprogramming enable targeted genome editing. In addition, the emergence of organoids and epigenetic drugs presents novel prospects for hearing restoration by manipulating regeneration pathways, making them promising methods for future regenerative treatments for hair cells. The potential of epigenetic modifiers as viable targets for pharmacological manipulation is becoming evident. Future therapies aimed at hair cell regeneration are particularly beneficial because of their advantage of restricting drug exposure within the inner ear.

Application of RNA-Seq Technology for Screening Reproduction-Related Differentially Expressed Genes in Tibetan and Yorkshire Pig Ovarian Tissue.

The purpose of this study was to explore and verify genes that regulate the reproductive traits of Tibetan pigs at the mRNA level. The ovarian tissues of Tibetan pigs (TPs) and Yorkshire pigs (YPs) were selected as research objects, and cDNA libraries of the ovarian tissue transcripts of Tibetan pigs and Yorkshire pigs were successfully constructed by the RNA-Seq technique. A total of 651 differentially expressed genes (DEGs) were screened, including 414 up-regulated genes and 237 down-regulated genes. Through GO and KEGG enrichment analysis, it was found that these differentially expressed genes were significantly enriched in cell process, reproductive process, reproduction, cell proliferation, binding, and catalytic activity, as well as oxidative phosphorylation, endocrine resistance, thyroid hormone, Notch, and other signal transduction pathways. Genes significantly enriched in pathways closely related to reproductive regulation were analyzed and selected, and the AR, CYP11A1, CYP17A1, INHBA, ARRB2, EGFR, ETS1, HSD17B1, IGF1R, MIF, SCARB1, and SMAD4 genes were identified as important candidate genes. Twelve differentially expressed genes related to reproduction were verified by RT-qPCR. The results showed that the expression of the AR, CYP17A1, EGFR, ETS1, IGF1R, and SMAD4 genes was significantly higher in Tibetan pigs than in Yorkshire pigs, while the expression of the CYP11A1, INHBA, ARRB2, HSD17B, MIF, and SCARB1 genes in Tibetan pigs was significantly lower than in Yorkshire pigs. The purpose of this study is to provide a theoretical basis for exploring the molecular mechanism of reproductive trait effect genes and the application of molecular breeding in Tibetan pigs.

The Notch inhibitor, FLI-06, increases the chemosensitivity of head and neck Squamous cell carcinoma cells to taxanes-based treatment

Aberration of Notch signaling is one of the key events involved in the development and progression of head and neck squamous cell carcinoma (HNSCC). The Notch pathway controls the tissue-specific differentiation of normal squamous epithelial cells and is frequently altered in squamous carcinomas, thus affecting their proliferation, growth, survival, and chemosensitivity or resistance against anti-cancer agents. In this study, we show that the use of novel, small-molecule inhibitors of Notch signaling, such as FLI-06, can have a beneficial effect on increasing the chemosensitivity of HNSCC to taxane-based chemotherapy. Inhibition of Notch signaling by FLI-06 alone virtually blocks the proliferation and growth of HNSCC cells in both 2D and 3D cultures and the zebrafish model, which is accompanied by down-regulation of key Notch target genes and proteins. Mechanistically, FLI-06 treatment causes cell cycle arrest in the G1-phase and induction of apoptosis in HNSCC, which is accompanied by increased c-JunS63 phosphorylation. Combining FLI-06 with Docetaxel shows a synergistic effect and partially blocks the cell growth of aggressive HNSCC cells via enhanced apoptosis and modification of c-JunS243 phosphorylation via GSK-3β inhibition. In conclusion, inhibition of Notch signaling in HNSCC cells that retain active Notch signaling significantly supports taxane-based anticancer activities via modulation of both the GSK-3β and the c-Jun.

Par3/bazooka binds NICD and promotes notch signaling during Drosophila development

The conserved bazooka (baz/par3) gene acts as a key regulator of asymmetrical cell divisions across the animal kingdom. Associated Par3/Baz-Par6-aPKC protein complexes are also well known for their role in the establishment of apical/basal cell polarity in epithelial cells. Here we define a novel, positive function of Baz/Par3 in the Notch pathway. Using Drosophila wing and eye development, we demonstrate that Baz is required for Notch signaling activity and optimal transcriptional activation of Notch target genes. Baz appears to act independently of aPKC in these contexts, as knockdown of aPKC does not cause Notch loss-of-function phenotypes. Using transgenic Notch constructs, our data positions Baz activity downstream of activating Notch cleavage steps and upstream of Su(H)/CSL transcription factor complex activity on Notch target genes. We demonstrate a biochemical interaction between NICD and Baz, suggesting that Baz is required for NICD activity before NICD binds to Su(H). Taken together, our data define a novel role of the polarity protein Baz/Par3, as a positive and direct regulator of Notch signaling through its interaction with NICD.

Activation of NOTCH signaling impedes cell proliferation and survival in acute megakaryoblastic leukemia

The genetic lesions that drive acute megakaryoblastic leukemia (AMKL) have not been fully elucidated. To search for genetic alterations in AMKL, we performed targeted deep sequencing in 34 AMKL patient samples and 8 AMKL cell lines and detected frequent genetic mutations in the NOTCH pathway in addition to previously reported alterations in GATA-1 and the JAK-STAT pathway. Pharmacological and genetic NOTCH activation, but not inhibition, significantly suppressed AMKL cell proliferation in both in vitro and in vivo assays employing a patient-derived xenograft model. These results suggest that NOTCH inactivation underlies AMKL leukemogenesis. and NOTCH activation holds the potential for therapeutic application in AMKL.

Targeted Metabolomics of Tissue and Plasma Identifies Biomarkers in Mice with NOTCH1-Dependent T-Cell Acute Lymphoblastic Leukemia.

While the genomics era has allowed remarkable advances in understanding the mechanisms driving the biology and pathogenesis of numerous blood cancers, including acute lymphoblastic leukemia (ALL), metabolic studies are still lagging, especially regarding how the metabolism differs between healthy and diseased individuals. T-cell ALL (T-ALL) is an aggressive hematological neoplasm deriving from the malignant transformation of T-cell progenitors characterized by frequent NOTCH1 pathway activation. The aim of our study was to characterize tumor and plasma metabolomes during T-ALL development using a NOTCH1-induced murine T-ALL model (ΔE-NOTCH1). In tissue, we found a significant metabolic shift with leukemia development, as metabolites linked to glycolysis (lactic acid) and Tricarboxylic acid cycle replenishment (succinic and malic acids) were elevated in NOTCH1 tumors, while metabolites associated with lipid oxidation (e.g., carnitine) as well as purine and pyrimidine metabolism were elevated in normal thymic tissue. Glycine, serine, and threonine metabolism, glutathione metabolism, as well as valine, leucine, and isoleucine biosynthesis were enriched pathways in tumor tissue. Phenylalanine and tyrosine metabolism was highly enriched in plasma from leukemia-bearing mice compared to healthy mice. Further, we identified a metabolic signature consisting of glycine, alanine, proline, 3-hydroxybutyrate, and glutamic acid as potential biomarkers for leukemia progression in plasma. Hopefully, the metabolic differences detected in our leukemia model will apply to humans and contribute to the development of metabolism-oriented therapeutic approaches.

Unraveling the intricate relationship between lipid metabolism and oncogenic signaling pathways.

Lipids, the primary constituents of the cell membrane, play essential roles in nearly all cellular functions, such as cell-cell recognition, signaling transduction, and energy provision. Lipid metabolism is necessary for the maintenance of life since it regulates the balance between the processes of synthesis and breakdown. Increasing evidence suggests that cancer cells exhibit abnormal lipid metabolism, significantly affecting their malignant characteristics, including self-renewal, differentiation, invasion, metastasis, and drug sensitivity and resistance. Prominent oncogenic signaling pathways that modulate metabolic gene expression and elevate metabolic enzyme activity include phosphoinositide 3-kinase (PI3K)/AKT, MAPK, NF-kB, Wnt, Notch, and Hippo pathway. Conversely, when metabolic processes are not regulated, they can lead to malfunctions in cellular signal transduction pathways. This, in turn, enables uncontrolled cancer cell growth by providing the necessary energy, building blocks, and redox potentials. Therefore, targeting lipid metabolism-associated oncogenic signaling pathways could be an effective therapeutic approach to decrease cancer incidence and promote survival. This review sheds light on the interactions between lipid reprogramming and signaling pathways in cancer. Exploring lipid metabolism as a target could provide a promising approach for creating anticancer treatments by identifying metabolic inhibitors. Additionally, we have also provided an overview of the drugs targeting lipid metabolism in cancer in this review.

Sequential light irradiation-controlled cancer stemness inhibition for sensitized photothermal therapy

Cancer stem-like cells (CSCs) have a well-established role in mediating tumor relapse and resistance towards chemotherapy and radiation therapy. Photothermal therapy (PTT) is an efficient therapeutic strategy that uses light and photothermal agents to generate hyperthermia in tumors and kill cancer cells. However, due to the heterogeneity and drug resistance of CSCs, some of them may survive from PTT and cause recurrence and metastasis of tumors. In the study, we present a sequential dual-wavelength light-controlled drug delivery strategy, which combines 656 nm light-triggered drug release to inhibit cancer stemness, followed by 808 nm light-activated PTT to eradicate bulk tumors. The first light irradiation induces the release of γ-secretase inhibitor MK-0752 to deactivate Notch pathway, which is a key regulator of CSCs. Subsequently, the second light irradiation triggers hyperthermia to effectively kill tumor cells. Our findings demonstrate that inhibiting cancer stemness increases tumor sensitivity to PTT, resulting in effective growth inhibition of primary tumors with repressed tumorgenicity. This innovative dual-wavelength strategy holds promise for enhancing the efficacy of PTT in addressing the challenges posed by CSCs-rooted heterogeneity and drug resistance.