The ligamentum flavum (LF) is a passive stabilizing tissue that connects two adjacent vertebral arches and contributes to the enclosure the spinal canal, thereby closing the entire canal posteriorly. However, a gap exists at the posterior atlanto-occipital and atlanto-axial interspaces, where the LF is absent and replaced by the myodural bridge (MDB), which attaches to the spinal dura mater. The reasons for this anatomical difference and how it arises during development remain unclear. There are notable structural differences between MDB and LF. The MDB consists primarily of type I collagen fibers, while the LF contains both collagen and elastin fibers, with the latter comprising a higher proportion. This study speculates that LOX and LOXL1, as key regulators of fiber synthesis, play an essential role in the development of MDB and LF. Differences in the expression of LOX and LOXL1, which are involved in collagen and elastin cross-linking, may be one of the main factors underlying this structural divergence in the posterior cervical interspace. This study examined the cervicooccipital regions of rat embryos and young rats using histology, immunohistochemistry, and RT-qPCR to compare morphological and developmental differences between the MDB and LF. Additional experiments using the BAPN inhibitor were conducted to investigate the expression patterns and functional differences of LOX and LOXL1 during the development of the MDB and LF. Our aim is to clarify the developmental processes of the MDB and LF, identify the causes of structural differences in the posterior cervical interspaces, and reveal the molecular mechanisms regulating their formation. The conclusion of the current study as follows: ①The MDB and LF exhibit distinct histological developmental patterns: cells and fibers in the MDB align in an organized manner later than those in the LF, while the MDB forms its complete structures earlier than the LF. ②LOX and LOXL1 play critical roles in collagen and elastic fibers formation, mediating fiber synthesis in both the MDB and LF. ③Differential expression of LOX and LOXL1 during development leads to variations in fiber composition and maturation timing between the MDB and LF, contributing to their structural differences in the posterior cervical spinal interspace.
The myodural bridge complex (MDBC) is a phylogenetically conserved composite anatomical structure that anchors the suboccipital musculature and nuchal ligament to the spinal dura mater (SDM) at the cranio-cervical junction, with species-specific morphological adaptations across vertebrates. Physiological functions of the MDBC include hypothesized mediation of cerebrospinal fluid (CSF) circulation dynamics, stabilizing the SDM during head movements to prevent dural folding, and transmitting proprioceptive signals from suboccipital musculature to the central nervous system. Clinical evidence increasingly links MDBC pathological alterations to a spectrum of cranio-cervical disorders, such as chronic cervicogenic headaches, Chiari malformation Type I, cervicogenic dizziness, and Ehlers-Danlos syndrome-associated symptoms. A comprehensive understanding of MDBC structure and function is critical to unraveling its putative mechanistic role in CSF homeostasis and cranio-cervical biomechanics, thereby providing novel insights for the diagnosis and management of related neurological conditions. This review systematically summarizes current knowledge of the MDBC in terms of its morphology, physiology, developmental biology and pathology.
Background and purpose: Breast cancer is one of the leading malignancies affecting women's health, with high incidence. Nucleotide-binding oligomerization domain containing 1 (NOD1), a member of the pattern recognition receptor family, is involved in regulating the immune microenvironment in various cancers. However, the specific regulatory functions and mechanisms of NOD1 in the breast cancer immune microenvironment remain unclear. This study aimed to investigate the effects of NOD1 on tumor-associated macrophages (TAM) within the breast cancer immune microenvironment and to explore the underlying mechanisms involved. Methods: The public databases and multiplex immunohistochemistry (mIHC) were utilized to analyze the correlation between NOD1 expression and immune infiltration in human breast cancer. Multicolor flow cytometry was performed to assess the immune cell composition and changes in NOD1-overexpressing breast tumor allografts. In vitro, chemotaxis assays and quantitative real-time polymerase chain reaction (qRT-PCR) were used to evaluate the effect of NOD1-overexpressing breast cancer cells on macrophage chemotaxis and polarization. Additionally, the effect of NOD1 on macrophage recruitment and polarization in breast tumor allografts was assessed by flow cytometry. Fluorescence-activated cell sorting (FACS) was used to isolate macrophages pre-conditioned by NOD1-overexpressing breast cancer stem cells, which were then cocultured with parental breast cancer cells. Flow cytometry was used to assess the impact of NOD1-conditioned macrophages on the stemness of breast cancer cells. Results: The database analysis and multicolor flow cytometry results demonstrated significant correlations between NOD1 expression and TAM infiltration (P<0.01). In vitro functional assays of macrophages demonstrated that NOD1-overexpressing breast cancer cells enhanced macrophage chemotaxis (P<0.001) and upregulated the expression of M2 macrophage markers. Compared with control groups, NOD1-overexpressing breast tumor allografts showed increased macrophage infiltration and polarization (P<0.01). NOD1-educated macrophages promoted malignant progression of breast cancer by increasing the proportion of breast cancer stem cells (P<0.05). Conclusion: In breast cancer, NOD1 remodels the immune microenvironment by recruiting macrophages and inducing their polarization towards the M2 phenotype. Furthermore, NOD1-educated macrophages enhance breast cancer cell stemness, thereby accelerating tumor progression. NOD1 represents a potential therapeutic target in breast cancer.
Research on the intratumoral microbiota is shifting from descriptive analyses of presence and abundance toward understanding its spatial heterogeneity and local function. Here we propose the concept of the microbiota-residing spatial niche (MRSN), defined as a functional unit formed by interactions between microbiota and neighboring tumor, immune, and stromal cells within a defined spatial context, and characterized by four key features: spatial discernibility, functional consistency, microbial dependency, and clinical relevance. In this review, we discuss the limitations of single-omics approaches and present a framework centered on spatial multi-omics. This framework integrates spatial transcriptomics, multiplex immunoimaging, spatial metabolomics, and graph neural networks, enabling a stepwise analysis that first localizes microbiota, then characterizes their surrounding cellular neighborhoods, and finally validates their functional roles. We classify MRSNs into immunosuppressive, immunostimulatory, protumorigenic, and antitumorigenic types, and demonstrate how they modulate therapy responses through local metabolic remodeling and immune regulation. We also contrast the systemic immunomodulatory effects of gut microbiota with the localized influence of intratumoral microbiota. Finally, we discuss challenges in technical validation, temporal dynamics, and model translation, and propose strategies for precision interventions targeting niche vulnerabilities and clinical stratification. This framework provides a unified conceptual basis for understanding intratumoral microbiota functions and informs next-generation spatially guided therapeutic strategies.
Triple-negative breast cancer (TNBC) is aggressive with limited therapies and poor prognosis. Butoconazole, a clinical topical imidazole antifungal for vulvovaginal candidiasis, has not previously been investigated for TNBC treatment. Here, we repurposed butoconazole as a novel allosteric inhibitor of glucose-regulated protein 78 (GRP78) for TNBC treatment. It suppressed TNBC cell proliferation (IC50: 13.61 ± 1.07 μM for MDA-MB-231, 26.17 ± 1.17 μM for MDA-MB-468), inhibited migration, and induced apoptosis, resulting in 68.28% tumor growth inhibition in MDA-MB-231 xenograft mouse models without evident toxicity. Mechanistically, we combined RNA-seq and limited proteolysis-mass spectrometry (LiP-MS) to identify GRP78 as its potential target, validated by surface plasmon resonance (SPR), biolayer interferometry (BLI), cellular thermal shift assay (CETSA), drug-affinity-responsive target-stability (DARTS) assay and molecular dynamics simulations. Unlike existing GRP78 modulators, butoconazole allosterically attaches to the helical bundle at the distal tip of GRP78 substrate-binding domain α (SBD-α), rearranges its binding pocket and blocks GRP78 chaperone activity. This triggers endoplasmic reticulum (ER) stress, elevates the expression levels of ATF4 and CHOP and induces apoptosis. Rescue assays with 4-phenylbutyrate (4-PBA), ATF4/CHOP knockdown or GRP78 overexpression attenuated butoconazole's anti-tumor activity. Collectively, butoconazole suppresses TNBC through allosteric GRP78 inhibition to trigger ER stress-mediated ATF4/CHOP apoptosis, and represents a promising lead compound for further development as a systemic anti-TNBC agent through formulation optimization.
Despite the pivotal role of tumor immune microenvironment (TIME) in breast cancer (BC) progression, the functional contributions of mast cells (MCs) within the TIME remain poorly understood. Utilizing single-cell RNA sequencing on tumor (T) and adjacent para-tumor (PT) tissues from BC patients, we identified a distinct transcriptional profile in T-derived tumor-resident MCs (MCt) compared to their PT counterparts. Survival analysis revealed that MCt signature gene set significantly correlated with poor clinical outcomes. To assess functional roles, we established in vitro co-culture systems and in vivo murine allograft models, which demonstrated that MCt promoted BC cell proliferation and enriched ALDH+ breast cancer stem cells (BCSCs). Mechanistically, through molecular inhibitors, agonist, recombinant protein, and gene-knockdown cell lines, we found that MCt-derived IFNB1 activated the Type I interferon pathway in BC cells via the IFNAR1-STAT1 axis. Reciprocally, BC cells upregulated IFNB1 expression in MCs via stem cell factor (SCF)-mediated c-KIT-MAPK/ERK signaling. This bidirectional crosstalk established a self-reinforcing IFNB1/SCF feedforward loop driving BC progression and stemness, which was further validated in BC patient tissues by multiplex immunohistochemistry. Collectively, our findings characterize a pro-tumorigenic MC subset within the TIME and propose a potential novel therapeutic strategy for BC by disrupting the MCt-BC cell interplay.
The myodural bridge (MDB) represents specialized fibrous structures establishing connectivity between suboccipital musculature and the spinal dura mater (SDM). The suboccipital muscles, ligaments, and myodural bridge fibers together form a functional unit known as the myodural bridge complex (MDBC). Mechanical stress from suboccipital muscles may contribute to MDB maturation. Integrin α7 (ITGA7) is critical for skeletal muscle attachment to connective tissues, and is involved in the transmission of lateral and longitudinal forces in skeletal muscle. Given the muscle force transmission characteristics of ITGA7 and the dependence of MDB development on force transmission, we hypothesized that ITGA7 serves as a crucial link between RCDmi and the MDB it emits, and may involve in the development of MDBC. To test this, neonatal Sprague-Dawley (SD) rats were randomly allocated to shRNA-ITGA7, shRNA-NC control, lentiviral vectors were injected into the dorsal atlanto-occipital interspace. ITGA7 suppression significantly impaired MDB development and maturation, manifesting as disrupted fiber assembly and RCDmi muscle dystrophy. Ultrastructural analysis revealed disorganized collagen fiber architecture and an abundance of fibroblasts, indicative of immature collagen fibers, further corroborated by Picrosirius red staining. Additionally, ITGA7 knockdown resulted in diminished RCDmi muscle force and altered ECM-related gene expression profiles. A key finding of our study is the importance of ITGA7 as a direct molecular link between suboccipital muscles and MDB, suggesting that mechanical forces from suboccipital musculature fundamentally influence MDB differentiation and maturation. These findings substantiate MDB's role in force transmission to the SDM and by extension, advance our understanding of the molecular mechanisms underlying MDB development and its physiological significance.
ObjectiveThe myodural bridge complex (MDBC) is a tendon-like structure highly conserved during vertebrate evolution, suggesting it plays an important physiological role. Substantial evidence indicates that the MDBC may contribute to cerebrospinal fluid (CSF) circulation by generating mechanical force. Studying its developmental process may offer new insights into CSF dynamics and lead to improved strategies for diagnosing and treating neurodegenerative diseases.Materials and MethodsThis study utilized utilized lentiviral plasmids to either knockdown or overexpress the Mkx gene in newborn Sprague-Dawley rats (SD) rats, establishing three groups: control, overexpression group, and interference group. Suboccipital injections were performed at birth. Histological staining and qPCR were conducted at multiple time points to assess the morphological and genetic impacts of Mkx modulation on the development of the MDBC.ResultsTransfection efficiency was confirmed by Green fluorescent protein (GFP) expression quantification, in vivo bioluminescent imaging, and Western blot validation in all experimental cohorts. Mkx knockdown exhibited diminished collagen fiber development accompanied by compensatory hyperplasia of occipital periosteum-derived fibrous tissues. Transcriptomic analysis revealed that Mkx overexpression upregulated tendon-related genes (Scx, Egr1) and downregulated myogenic regulators (Myod), with inverse expression patterns observed in knockdown models. Pathway gene analysis identified the TGF-β signaling cascade and associated mechanosensitive genes as central regulators of the MDBC.ConclusionMkx exerts bidirectional regulation on MDBC development by modulating the TGF-β signaling pathway. Overexpression of Mkx promotes collagen deposition and structural reinforcement in MDBC through coordinated molecular mechanisms: upregulating Scx/Egr1 expression, downregulating Myod, and inducing hyperplastic growth of deep fascial fibers in the rectus capitis dorsal minor muscle (RCDmi). Conversely, Mkx suppression maintains tissue integrity through three synergistic mechanisms: upregulating Myod expression, inducing MDBC fiber proliferation, and facilitating adaptive remodeling of the posterior atlanto-occipital membrane (PAOM). At the molecular level, Mkx coordinates differentiation processes through dynamic equilibrium of Scx/Egr1/Myod expression profiles while constructing regulatory networks that couple biomechanical-chemical signals via TGF-β pathway activation.
Tumor-resident microbiota in breast cancer promotes cancer initiation and malignant progression. However, targeting microbiota to improve the effects of breast cancer therapy has not been investigated in detail. Here, we evaluated the microbiota composition of breast tumors and found that enterotoxigenic Bacteroides fragilis (ETBF) was highly enriched in the tumors of patients who did not respond to taxane-based neoadjuvant chemotherapy. ETBF, albeit at low biomass, secreted the toxic protein BFT-1 to promote breast cancer cell stemness and chemoresistance. Mechanistic studies showed that BFT-1 directly bound to NOD1 and stabilized NOD1 protein. NOD1 was highly expressed on ALDH+ breast cancer stem cells (BCSCs) and cooperated with GAK to phosphorylate NUMB and promote its lysosomal degradation, thereby activating the NOTCH1-HEY1 signaling pathway to increase BCSCs. NOD1 inhibition and ETBF clearance increase the chemosensitivity of breast cancer by impairing BCSCs.
Neurotransmitters are increasingly recognized to play important roles in limiting anti-tumor immunity. N-acetyl-aspartyl-glutamate (NAAG) has been extensively studied in neurological disorders; however, its potential role in restricting anti-tumor immunity has not been investigated. Here, we demonstrated that NAAG or its synthetase RimK-like family member B (RIMKLB) significantly disrupted anti-tumor immunity by rewiring the myeloid progenitor differentiation of polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs), which in turn promoted breast cancer growth and metastasis. Mechanistically, NAAG sustained the tumor immunosuppressive microenvironment by activating an NR2B-containing NMDA receptor (NR2B-NMDAR)-dependent p38-NOTCH1 axis, and subsequently stimulating tumor cell migration and invasion, as well as inducing PMN-MDSC differentiation and expansion. In mouse models, RIMKLB ablation or NMDAR inhibition enhanced the efficacy of anti-PD-1 therapy and suppressed tumor progression. An analysis of clinical samples revealed that high levels of NAAG and NR2B-NMDAR predicted a poor prognosis in TNBC patients. Collectively, our findings have uncovered a signaling role for tumor-derived NAAG beyond its classic function as a neurotransmitter that can be targeted pharmacologically to enhance immunotherapy against breast cancer.
Polypeptide N-acetylgalactosamine transferase 9 (GALNT9) catalyzes the initial step of mucin-type O-glycosylation via linking N-acetylgalactosamine (GalNAc) to serine/threonine in a protein. To unravel the association of GALNT9 with Parkinson's disease (PD), a progressive neurodegenerative disorder, GALNT9 levels were evaluated in the patients with PD and mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine, and statistically analyzed based on the GEO datasets of GSE114918 and GSE216281. Glycoproteins with exposing GalNAc were purified using lectin affinity chromatography and identified by LC-MS/MS. The influence of GALNT9 on cells was evaluated via introducing a GALNT9-specific siRNA into SH-SY5Y cells. Consequently, GALNT9 deficiency was found to occur under PD conditions. GALNT9 silencing contributed to a causative factor in PD pathogenesis via reducing the levels of intracellular dopamine, tyrosine hydroxylase and soluble α-synuclein, and promoting α-synuclein aggregates. MS identification revealed 14 glycoproteins. 5 glycoproteins, including ACO2, ATP5B, CKB, CKMT1A, ALDOC, were associated with energy metabolism. GALNT9 silencing resulted in mitochondrial dysfunctions via increasing ROS accumulation, mitochondrial membrane depolarization, mPTPs opening, Ca2+ releasing and activation of the CytC-related apoptotic pathway. The dysfunctional mitochondria then triggered mitophagy, possibly intermediated by adenine nucleotide translocase 1. Our study suggests that GALNT9 is potentially developed into an auxiliary diagnostic index and therapeutic target of PD.
Breast tumor-initiating cells (BTICs) of triple-negative breast cancer (TNBC) tissues actively repair DNA and are resistant to treatments including chemotherapy, radiotherapy, and targeted therapy. Herein, it is found that a previously reported secreted protein, sclerostin domain containing 1 (SOSTDC1), is abundantly expressed in BTICs of TNBC cells and positively correlated with a poor patient prognosis. SOSTDC1 knockdown impairs homologous recombination (HR) repair, BTIC maintenance, and sensitized bulk cells and BTICs to Olaparib. Mechanistically, following Olaparib treatment, SOSTDC1 translocates to the nucleus in an importin-α dependent manner. Nuclear SOSTDC1 interacts with the N-terminus of the nucleoprotein, chromatin helicase DNA-binding factor (CHD1), to promote HR repair and BTIC maintenance. Furthermore, nuclear SOSTDC1 bound to β-transducin repeat-containing protein (β-TrCP) binding motifs of CHD1 is found, thereby blocking the β-TrCP-CHD1 interaction and inhibiting β-TrCP-mediated CHD1 ubiquitination and degradation. Collectively, these findings identify a novel nuclear SOSTDC1 pathway in regulating HR repair and BTIC maintenance, providing insight into the TNBC therapeutic strategies.
Our previous studies have showed that C-C motif chemokine ligand 20 (CCL20) advanced tumor progression and enhanced the chemoresistance of cancer cells by positively regulating breast cancer stem cell (BCSC) self-renewal. However, it is unclear whether CCL20 affects breast cancer progression by remodeling the tumor microenvironment (TME). Here, we observed that polymorphonuclear myeloid-derived suppressor cells (PMN-MDSCs) were remarkably enriched in TME of CCL20-overexpressing cancer cell orthotopic allograft tumors. Mechanistically, CCL20 activated the differentiation of granulocyte-monocyte progenitors (GMPs) via its receptor C-C motif chemokine receptor 6 (CCR6) leading to the PMN-MDSC expansion. PMN-MDSCs from CCL20-overexpressing cell orthotopic allograft tumors (CCL20-modulated PMN-MDSCs) secreted amounts of C-X-C motif chemokine ligand 2 (CXCL2) and increased ALDH+ BCSCs via activating CXCR2/NOTCH1/HEY1 signaling pathway. Furthermore, C-X-C motif chemokine receptor 2 (CXCR2) antagonist SB225002 enhanced the docetaxel (DTX) effects on tumor growth by decreasing BCSCs in CCL20high-expressing tumors. These findings elucidated how CCL20 modulated the TME to promote cancer development, indicating a new therapeutic strategy by interfering with the interaction between PMN-MDSCs and BCSCs in breast cancer, especially in CCL20high-expressing breast cancer.
Conventional beamforming with fixed-position antenna (FPA) arrays has a fundamental trade-off between maximizing the signal power (array gain) over a desired direction and simultaneously minimizing the interference power over undesired directions. To overcome this limitation, this letter investigates the movable antenna (MA) array enhanced beamforming by exploiting the new degree of freedom (DoF) via antenna position optimization, in addition to the design of antenna weights. We show that by jointly optimizing the antenna positions vector (APV) and antenna weights vector (AWV) of a linear MA array, the full array gain can be achieved over the desired direction while null steering can be realized over all undesired directions, under certain numbers of MAs and null-steering directions. The optimal solutions for AWV and APV are derived in closed form, which reveal that the optimal AWV for MA arrays requires only the signal phase adjustment with a fixed amplitude. Numerical results validate our analytical solutions for MA array beamforming and show their superior performance to the conventional beamforming techniques with FPA arrays.
Background Although the antitumor efficacy of docetaxel (DTX) has long been attributed to the antimitotic activities, its impact on the tumor microenvironment (TME) has recently gained more attention. Macrophages are a major component of the TME and play a critical role in DTX efficacy; however, the underlying action mechanisms remain unclear.Methods DTX chemotherapeutic efficacy was demonstrated via both macrophage depletion and C–C motif chemokine ligand 3 (Ccl3)-knockout transgenic allograft mouse model. Ccl3-knockdown and Ccl3-overexpressing breast cancer cell allografts were used for the in vivo study. Combination therapy was used to evaluate the effect of Ccl3 induction on DTX chemosensitivity. Vital regulatory molecules and pathways were identified using RNA sequencing. Macrophage phagocytosis of cancer cells and its influence on cancer cell proliferation under DTX treatment were assessed using an in vitro coculture assay. Serum and tumor samples from patients with breast cancer were used to demonstrate the clinical relevance of our study.Results Our study revealed that Ccl3 induced by DTX in macrophages and cancer cells was indispensable for the chemotherapeutic efficacy of DTX. DTX-induced Ccl3 promoted proinflammatory macrophage polarization and subsequently facilitated phagocytosis of breast cancer cells and cancer stem cells. Ccl3 overexpression in cancer cells promoted proinflammatory macrophage polarization to suppress tumor progression and increase DTX chemosensitivity. Mechanistically, DTX induced Ccl3 by relieving the inhibition of cAMP-response element binding protein on Ccl3 via reactive oxygen species accumulation, and Ccl3 then promoted proinflammatory macrophage polarization via activation of the Ccl3–C-C motif chemokine receptor 5–p38/interferon regulatory factor 5 pathway. High CCL3 expression predicted better prognosis, and high CCL3 induction revealed better DTX chemosensitivity in patients with breast cancer. Furthermore, both the Creb inhibitor and recombinant mouse Ccl3 significantly enhanced DTX chemosensitivity.Conclusions Our results indicate that Ccl3 induced by DTX triggers proinflammatory macrophage polarization and subsequently facilitates phagocytosis of cancer cells. Ccl3 induction in combination with DTX may provide a promising therapeutic rationale for increasing DTX chemosensitivity in breast cancer.
Cuproptosis is a newly defined programmed cell death pattern and is believed to play an important role in tumorigenesis and progression. In addition, many studies have shown that glycosylation modification is of vital importance in tumor progression. However, it remains unclear whether glycosyltransferases, the most critical enzymes involved in glycosylation modification, are associated with cuproptosis. In this study, we used bioinformatic methods to construct a signature of cuproptosis-related glycosyltransferases to predict the prognosis of colon adenocarcinoma patients. We found that cuproptosis was highly correlated with four glycosyltransferases in COAD, and our model predicted the prognosis of COAD patients. Further analysis of related functions revealed the possibility that cuproptosis-related glycosyltransferase Exostosin-like 2 (EXTL2) participated in tumor immunity.
Ribophorin 1 (RPN1) is a major part of Oligosaccharyltransferase (OST) complex, which is vital for the N-linked glycosylation. Though it has been verified that the abnormal glycosylation is closely related to the development of breast cancer, the detail role of RPN1 in breast cancer remains unknown. In this study, we explored the public databases to investigate the relationship between the expression levels of OST subunits and the prognosis of breast cancer. Then, we focused on the function of RPN1 in breast cancer and its potential mechanisms. Our study showed that the expression of several OST subunits including RPN1, RPN2, STT3A STT3B, and DDOST were upregulated in breast cancer samples. The protein expression level of RPN1 was also upregulated in breast cancer. Higher expression of RPN1 was correlated with worse clinical features and poorer prognosis. Furthermore, knockdown of RPN1 suppressed the proliferation and invasion of breast cancer cells in vitro and induced cell apoptosis triggered by endoplasmic reticulum stress. Our results identified the oncogenic function of RPN1 in breast cancer, implying that RPN1 might be a potential biomarker and therapeutic target for breast cancer.
Purpose: TFEB is a key regulator of autophagy-lysosomal biogenesis pathways, while its dysregulation is highly prevalent in various human cancers, but the specific contribution to breast cancer remains poorly understood. The main purpose of this study is to explore the role of TFEB in breast cancer proliferation, metastasis and maintaining breast cancer stem cells (BCSCs) traits, thus uncovering its underlying mechanism. Methods: Bioinformatics, western blotting and immunohistochemical staining were applied to analyze the expression of TFEB in breast cancer. Stable down-regulation TFEB cells were established in MCF-7 and MDA-MB-231 breast cancer cell lines. MTT, clone formation, wound healing, transwell and 3D tumor invasion assays were used to evaluate the proliferation, migration and invasion ability of breast cancer cells. Mammosphere formation, immunocytochemical (ICC) staining were used to detect the effect of down-regulating TFEB on breast cancer stem cells. Results: we demonstrated that higher expression of TFEB was found in breast cancer. TFEB depletion had inhibitory effects on cellular proliferation, migration and invasion of breast cancer cells. Moreover, knockdown TFEB decreased mammosphere formation ability of BCSCs and expression of cancer stem cell markers. Autophagy-lysosomal related proteins were decreased by down regulation of TFEB. Conclusion: we uncovered a critical role of TFEB in breast cancer proliferation and metastasis, and BCSCs self-renewal and stemness. The underlying mechanisms involve in maintaining BCSCs traits, and dysregulating lysosome functions.
Abdominal aortic aneurysm (AAA) is a serious vascular disease featured by inflammatory infiltration in aortic wall, aortic dilatation and extracellular matrix (ECM) degradation. Dysregulation of microRNAs (miRNAs) is implicated in AAA progress. By profiling miRNA expression in mouse AAA tissues and control aortas, we noted that miR‐126a‐5p was down‐regulated by 18‐fold in AAA samples, which was further validated with real‐time qPCR. This study was performed to investigate miR‐126a‐5p's role in AAA formation. In vivo, a 28‐d infusion of 1 μg/kg/min Angiotensin (Ang) II was used to induce AAA formation in Apoe ‐/‐ mice. MiR‐126a‐5p (20 mg/kg; MIMAT0000137) or negative control (NC) agomirs were intravenously injected to mice on days 0, 7, 14 and 21 post‐Ang II infusion. Our data showed that miR‐126a‐5p overexpression significantly improved the survival and reduced aortic dilatation in Ang II‐infused mice. Elastic fragment and ECM degradation induced by Ang II were also ameliorated by miR‐126a‐5p. A strong up‐regulation of ADAM metallopeptidase with thrombospondin type 1 motif 4 (ADAMTS‐4), a secreted proteinase that regulates matrix degradation, was observed in smooth muscle cells (SMCs) of aortic tunica media, which was inhibited by miR‐126a‐5p. Dual‐luciferase results demonstrated ADAMTS‐4 as a new and valid target for miR‐126a‐5p. In vitro, human aortic SMCs (hASMCs) were stimulated by Ang II. Gain‐ and loss‐of‐function experiments further confirmed that miR‐126‐5p prevented Ang II‐induced ECM degradation, and reduced ADAMTS‐4 expression in hASMCs. In summary, our work demonstrates that miR‐126a‐5p limits experimental AAA formation and reduces ADAMTS‐4 expression in abdominal aortas.
The aim of this study was to investigate the possible influences of circPRKCI abnormal expression on lipopolysaccharide (LPS)-induced HK2 cell injury and its mechanism. The circPRKCI level was identified in serum samples from patients with urosepsis and healthy subjects, as well as LPS-treated HK2 cells by qRT-PCR. Cell viability, apoptosis, expression of proteins associated with apoptosis, and expression of pro-inflammatory cytokines in LPS-treated HK2 cells were measured. Effects of circPRKCI abnormal expression on LPS-induced HK2 cell injury were then evaluated. Afterward, the binding miRNA of circPRKCI and target gene of miRNA were identified, and the involvements of NF-kB pathway signaling pathway with the effects of circPRKCI were finally studied. CircPRKCI was significantly down-regulated in serum samples from patients with urosepsis and LPS-treated HK2 cells. LPS-induced decrease of cell viability, increase of cell apoptosis, as well as elevated productions of tumor necrosis factor (TNF)-α, interleukins (IL)-1β, IL-6, and IL-8 in HK2 cells were attenuated by overexpressed circPRKCI. In addition, circPRKCI negatively regulated the expression of miR-545, and miR-545 up-regulation reversed the inhibiting effects of circPRKCI overexpression on LPS-induced HK2 cell injury. Moreover, zinc finger E-box-binding homeobox 2 (ZEB2) was identified as a target gene of miR-545, and ZEB2 overexpression partly reversed the effects of miR-545 up-regulation on LPS-induced HK2 cell injury. Furthermore, NF-kB pathway was revealed to be associated to the effects of circPRKCI on LPS-induced HK2 cell injury. This research indicated that the highly expressed circPRKCI relieved inflammatory injury induced by LPS in HK2 cells by suppressing miR-545/ZEBs and depressing the briskness of NF-kB pathway.