NUMB and NUMBL differences in gene regulation

Targeting signaling pathways in cancer stem cells: A potential approach for developing novel anti-cancer therapeutics

Cancer stem cells (CSCs) have emerged as prime players in the intricate landscape of cancer development, progression, and resistance to traditional treatments. These unique cellular subpopulations own the remarkable capability of self-renewal and differentiation, giving rise to the diverse cellular makeup of tumors and fostering their recurrence following conventional therapies. In the quest for developing more effective cancer therapeutics, the focus has now shifted toward targeting the signaling pathways that govern CSCs behavior. This chapter underscores the significance of these signaling pathways in CSC biology and their potential as pivotal targets for the development of novel chemotherapy approaches. We delve into several key signaling pathways essential for maintaining the defining characteristics of CSCs, including the Wnt, Hedgehog, Notch, JAK-STAT, NF-κB pathways, among others, shedding light on their potential crosstalk. Furthermore, we highlight the latest advancements in CSC-targeted therapies, spanning from promising preclinical models to ongoing clinical trials. A comprehensive understanding of the intricate molecular aspects of CSC signaling pathways and their manipulation holds the prospective to revolutionize cancer treatment paradigms. This, in turn, could lead to more efficacious and personalized therapies with the ultimate goal of eradicating CSCs and enhancing overall patient outcomes. The exploration of CSC signaling pathways represents a key step towards a brighter future in the battle against cancer.

Comprehensive pan-cancer analysis of expression profiles and prognostic significance for NUMB and NUMBL in human tumors

NUMB has been initially identified as a critical cell fate determinant that modulates cell differentiation via asymmetrical partitioning during mitosis, including tumor cells. However, it remains absent that a systematic assessment of the mechanisms underlying NUMB and its homologous protein NUMBLIKE (NUMBL) involvement in cancer. This study aimed to investigate the prognostic significance for NUMB and NUMBL in pan-cancer. In this study, using the online databases TIMER2.0, gene expression profiling interactive analysis, cBioPortal, the University of ALabama at Birmingham CANcer data analysis Portal, SearchTool for the Retrieval of Interacting Genes/Proteins, and R software, we focused on the relevance between NUMB/NUMBL and oncogenesis, progression, mutation, phosphorylation, function and prognosis. This study demonstrated that abnormal expression of NUMB and NUMBL were found to be significantly associated with clinicopathologic stages and the prognosis of survival. Besides, genetic alternations of NUMB and NUMBL focused on uterine corpus endometrial carcinoma, and higher genetic mutations of NUMBL were correlated with more prolonged overall survival and disease-free survival in different cancers. Moreover, S438 locus of NUMB peptide fragment was frequently phosphorylated in 4 cancer types and relevant to its phosphorylation sites. Furthermore, endocytosis processing and neurogenesis regulation were involved in the functional mechanisms of NUMB and NUMBL separately. Additionally, the pathway enrichment suggested that NUMB was implicated in Hippo, Neurotrophin, Thyroid hormone, and FoxO pathways, while MAPK, Hippo, Rap1, mTOR, and Notch pathways were related to the functions of NUMBL. This study highlights the predictive roles of NUMB and NUMBL in pan-cancer, suggesting NUMB and NUMBL might be served as potential biomarkers for diagnosis and prognosis in various malignant tumors.

Targeting crosstalk of signaling pathways in cancer stem cells: a promising approach for development of novel anti-cancer therapeutics

Wnt, Hedgehog (Hh), and Notch signaling pathways are the evolutionarily conserved signaling pathways that regulate the embryonic development and also play crucial role in maintaining stemness properties of cancer stem cells (CSCs) and inducing epithelial-to-mesenchymal transition (EMT), metastasis, and angiogenesis. It has been highly challenging to inhibit the CSCs growth and proliferation as these are capable of evading chemotherapeutic drugs and cause cancer recurrence through multiple signaling pathways. Therefore, novel therapeutic strategies to target the key players involved in the crosstalk of these signaling pathways need to be developed. In this review, we have identified the interacting molecules of Wnt, Hh, and Notch pathways responsible for enhancing the malignant properties of CSCs. Analyzing the functions of these crosstalk molecules will help us to find an approach toward the development of new anti-cancer drugs for inhibition of CSCs growth and progression. Long non-coding RNAs (LncRNAs) play a significant role in various cellular processes, like chromatin remodeling, epigenetic modifications, transcriptional, and post-transcriptional regulations. Here, we have highlighted the research findings suggesting the involvement of LncRNAs in maintenance of the stemness properties of CSCs through modulation of the above-mentioned signaling pathways. We have also discussed about the different therapeutic approaches targeting those key players responsible for mediating the crosstalk between the pathways. Overall, this review article will surely help the cancer biologists to design novel anti-CSCs agents that will open up a new horizon in the field of anti-cancer therapeutics.

The Multitasker Protein: A Look at the Multiple Capabilities of NUMB

NUMB, a plasma membrane-associated protein originally described in Drosophila, is involved in determining cell function and fate during early stages of development. It is secreted asymmetrically in dividing cells, with one daughter cell inheriting NUMB and the other inheriting its antagonist, NOTCH. NUMB has been proposed as a polarizing agent and has multiple functions, including endocytosis and serving as an adaptor in various cellular pathways such as NOTCH, Hedgehog, and the P53-MDM2 axis. Due to its role in maintaining cellular homeostasis, it has been suggested that NUMB may be involved in various human pathologies such as cancer and Alzheimer's disease. Further research on NUMB could aid in understanding disease mechanisms and advancing the field of personalized medicine and the development of new therapies.

MAD2B promotes podocyte injury through regulating Numb-dependent Notch 1 pathway in diabetic nephropathy

Rationale: Recent studies have demonstrated that the loss of podocyte is a critical event in diabetic nephropathy (DN). Previously, our group have found that the mitotic arrest deficient protein MAD2B was involved in high glucose (HG)-induced podocyte injury by regulating APC/C activity. However, the exact mechanism of MAD2B implicated in podocyte injury is still lacking. Methods: The experiments were conducted by using kidney tissues from streptozotocin (STZ) induced diabetic mice with or without podocyte-specific deletion of MAD2B and the cultured podocytes exposed to different treatments. Glomerular pathological injury was evaluated by periodic acid-Schiff staining and transmission electron microscopy. The endogenous interaction between MAD2B and Numb was discovered by yeast two-hybrid analysis and co-immunoprecipitation assay. The expressions of MAD2B, Numb and related pathway were detected by western blot, immunochemistry and immunofluorescence. Results: The present study revealed that MAD2B was upregulated in diabetic glomeruli and cultured podocytes under hyperglycemic conditions. Podocyte-specific deletion of MAD2B alleviated podocyte injury and renal function deterioration in mice of diabetic nephropathy. Afterwards, MAD2B was found to interact with Numb, which was downregulated in diabetic glomeruli and HG-stimulated cultured podocytes. Interestingly, MAD2B genetic deletion could partly reverse the decline of Numb in podocytes exposed to HG and in diabetic mice, and the expressions of Numb downstream molecules such as NICD and Hes-1 were decreased accordingly. In addition, overexpression of Numb ameliorated HG-induced podocyte injury. Conclusions: The present findings suggest that upregulated MAD2B expression contributes to Numb depletion and activation of Notch 1 signaling pathway, which ultimately leads to podocyte injury during DN progression.

Numb is required for optimal contraction of skeletal muscle

BACKGROUND

The role of Numb, a protein that is important for cell fate and development and that, in human muscle, is expressed at reduced levels with advanced age, was investigated; adult mice skeletal muscle and its localization and function within myofibres were determined.

METHODS

Numb expression was evaluated by western blot. Numb localization was determined by confocal microscopy. The effects of conditional knock out (cKO) of Numb and the closely related gene Numb-like in skeletal muscle fibres were evaluated by in situ physiology, transmission and focused ion beam scanning electron microscopy, three-dimensional reconstruction of mitochondria, lipidomics, and bulk RNA sequencing. Additional studies using primary mouse myotubes investigated the effects of Numb knockdown on cell fusion, mitochondrial function, and calcium transients.

RESULTS

Numb protein expression was reduced by ~70% (P < 0.01) at 24 as compared with 3 months of age in gastrocnemius and tibialis anterior muscle. Numb was localized within muscle fibres as bands traversing fibres at regularly spaced intervals in close proximity to dihydropyridine receptors. The cKO of Numb and Numb-like reduced specific tetanic force by 36% (P < 0.01), altered mitochondrial spatial relationships to sarcomeric structures, increased Z-line spacing by 30% (P < 0.0001), perturbed sarcoplasmic reticulum organization and reduced mitochondrial volume by over 80% (P < 0.01). Only six genes were differentially expressed in cKO mice: Itga4, Sema7a, Irgm2, Vezf1, Mib1, and Tmem132a. Several lipid mediators derived from polyunsaturated fatty acids through lipoxygenases were up-regulated in Numb cKO skeletal muscle: 12-HEPE was increased by ~250% (P < 0.05) and 17,18-EpETE by ~240% (P < 0.05). In mouse primary myotubes, Numb knockdown reduced cell fusion (~20%, P < 0.01) and delayed the caffeine-induced rise in cytosolic calcium concentrations by more than 100% (P < 0.01).

CONCLUSIONS

These findings implicate Numb as a critical factor in skeletal muscle structure and function and suggest that Numb is critical for calcium release. We therefore speculate that Numb plays critical roles in excitation-contraction coupling, one of the putative targets of aged skeletal muscles. These findings provide new insights into the molecular underpinnings of the loss of muscle function observed with sarcopenia.

From Benign Inflammatory Dermatosis to Cutaneous Lymphoma. DNA Copy Number Imbalances in Mycosis Fungoides versus Large Plaque Parapsoriasis

Background and Objectives: Mycosis fungoides (MF) and large plaque parapsoriasis (LPP) evolution provide intriguing data and are the cause of numerous debates. The diagnosis of MF and LPP is associated with confusion and imprecise definition. Copy number alterations (CNAs) may play an essential role in the genesis of cancer out of genes expression dysregulation. Objectives: Due to the heterogeneity of MF and LPP and the scarcity of the cases, there are an exceedingly small number of studies that have identified molecular changes in these pathologies. We aim to identify and compare DNA copy number alterations and gene expression changes between MF and LPP to highlight the similarities and the differences between these pathologies. Materials and Methods: The patients were prospectively selected from University Clinic of Dermatology and Venereology Timișoara, Romania. From fresh frozen skin biopsies, we extracted DNA using single nucleotide polymorphism (SNP) data. The use of SNP array for copy number profiling is a promising approach for genome-wide analysis. Results: After reviewing each group, we observed that the histograms generated for chromosome 1–22 were remarkably similar and had a lot of CNAs in common, but also significant differences were seen. Conclusions: This study took a step forward in finding out the differences and similarities between MF and LPP, for a more specific and implicitly correct approach of the case. The similarity between these two pathologies in terms of CNAs is striking, emphasizing once again the difficulty of approaching and differentiating them.

Inhibitory effects of Lactobacilli cocktail on HT-29 colon carcinoma cells growth and modulation of the Notch and Wnt/β-catenin signaling pathways

Probiotics could be considered as attractive candidates for preventing tumor growth through maintaining homeostasis. The aim of this study was to evaluate the inhibitory effect of a cocktail of five Lactobacillus species on human colorectal carcinoma cell line HT-29. The anti-proliferative and apoptotic effects of Lactobacilli cocktail were evaluated using MTT and flow cytometry tests, respectively. Quantitative real-time polymerase chain reaction (qPCR) was used to analyze the expression of several genes in the Notch (notch, hes1, msi1, and numb) and Wnt/β-catenin (CTNNB1 and CCND1) pathways, following the treatment of HT-29 cells with Lactobacilli cocktail. The treatment by Lactobacilli cocktail induced a significant anti-proliferative effect and late stage apoptosis among the cancer cells (p < 0.05). Compared to the untreated cells, Lactobacilli cocktail induced the down-regulation of notch, hes1, and msi1 genes and up-regulation of numb gene in the Notch pathway as well as the down-regulation of CTNNB1 and CCND1 genes in the Wnt/β-catenin pathway in a time-dependent manner (p < 0.05). CONCLUSION: Lactobacilli cocktail was shown to have beneficial anti-tumor effects on HT-29 cells by modulating the Notch and Wnt/β-catenin pathways; therefore, the use of Lactobacilli probiotics as nutritional supplements may prevent the incidence of colon cancer.

Small Extracellular Vesicles Released from Ovarian Cancer Spheroids in Response to Cisplatin Promote the Pro-Tumorigenic Activity of Mesenchymal Stem Cells

Despite the different strategies used to treat ovarian cancer, around 70% of women/patients eventually fail to respond to the therapy. Cancer stem cells (CSCs) play a role in the treatment failure due to their chemoresistant properties. This capacity to resist chemotherapy allows CSCs to interact with different components of the tumor microenvironment, such as mesenchymal stem cells (MSCs), and thus contribute to tumorigenic processes. Although the participation of MSCs in tumor progression is well understood, it remains unclear how CSCs induce the pro-tumorigenic activity of MSCs in response to chemotherapy. Small extracellular vesicles, including exosomes, represent one possible way to modulate any type of cell. Therefore, in this study, we evaluate if small extracellular vesicle (sEV) derived from ovarian cancer spheroids (OCS), which are enriched in CSCs, can modify the activity of MSCs to a pro-tumorigenic phenotype. We show that sEV released by OCS in response to cisplatin induce an increase in the migration pattern of bone marrow MSCs (BM-MSCs) and the secretion interleukin-6 (IL-6), interleukin-8 (IL-8), and vascular endothelial growth factor A (VEGFA). Moreover, the factors secreted by BM-MSCs induce angiogenesis in endothelial cells and the migration of low-invasive ovarian cancer cells. These findings suggest that cisplatin could modulate the cargo of sEV released by CSCs, and these exosomes can further induce the pro-tumorigenic activity of MSCs.

Overexpression of miRNA-25-3p inhibits Notch1 signaling and TGF-β-induced collagen expression in hepatic stellate cells

During chronic liver injury hepatic stellate cells (HSCs), the principal source of extracellular matrix in the fibrotic liver, transdifferentiate into pro-fibrotic myofibroblast-like cells - a process potentially regulated by microRNAs (miRNAs). Recently, we found serum miRNA-25-3p (miR-25) levels were upregulated in children with Cystic Fibrosis (CF) without liver disease, compared to children with CF-associated liver disease and healthy individuals. Here we examine the role of miR-25 in HSC biology. MiR-25 was detected in the human HSC cell line LX-2 and in primary murine HSCs, and increased with culture-induced activation. Transient overexpression of miR-25 inhibited TGF-β and its type 1 receptor (TGFBR1) mRNA expression, TGF-β-induced Smad2 phosphorylation and subsequent collagen1α1 induction in LX-2 cells. Pull-down experiments with biotinylated miR-25 revealed Notch signaling (co-)activators ADAM-17 and FKBP14 as miR-25 targets in HSCs. NanoString analysis confirmed miR-25 regulation of Notch- and Wnt-signaling pathways. Expression of Notch signaling pathway components and endogenous Notch1 signaling was downregulated in miR-25 overexpressing LX-2 cells, as were components of Wnt signaling such as Wnt5a. We propose that miR-25 acts as a negative feedback anti-fibrotic control during HSC activation by reducing the reactivity of HSCs to TGF-β-induced collagen expression and modulating the cross-talk between Notch, Wnt and TGF-β signaling.