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1.
Cureus ; 15(10): e46339, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37920641

ABSTRACT

We present a rare case of Anaplastic Lymphoma Kinase (ALK)-rearranged lung cancer characterized by isolated scattered mucin-free cancer cells forming no clusters in the cytology of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) samples from a paratracheal lymph node. A female patient in her late 40s underwent chest and abdominal CT scan, revealing a 6 cm diameter tumor in the upper lobe of the left lung along with enlargement of mediastinal and hilar lymph nodes, bilateral pleural effusion, and an additional 5.5 cm diameter tumor in the right greater psoas muscle. EBUS-TBNA was performed to obtain samples for cytological and histological examination. Cytology showed exclusively solitary cancer cells that were negative for Periodic Acid-Schiff (PAS) and Alcian blue staining, without clusters. Immunohistochemical analysis of cell block and histology specimens demonstrated positive expression of TTF-1, ALK, and vimentin, while E-cadherin expression was absent. Genetic analysis of samples obtained by EBUS-TBNA confirmed the presence of EML4-ALK fusion. The tumor in the right greater psoas muscle was identified as a metastatic tumor from the lung tumor based on ALK-positivity and the EML4-ALK fusion. The absence of E-cadherin expression and the presence of vimentin expression suggest that this ALK-rearranged lung cancer may have undergone epithelial-mesenchymal transition, resulting in the loss of cellular adhesiveness.

2.
Biomedicines ; 11(8)2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37626774

ABSTRACT

Accumulation of 4-hydroxynonenal (4-HNE), a marker of lipid peroxidation, has various favorable and unfavorable effects on cancer cells; however, the clinicopathological significance of its accumulation in hepatocellular carcinoma (HCC) and its metabolic pathway remain unknown. This study analyzed 4-HNE accumulation and its clinicopathological significance in HCC. Of the 221 cases, 160 showed relatively low accumulation of 4-HNE in HCC tissues, which was an independent prognostic predictor. No correlation was found between 4-HNE accumulation and the expression of the antioxidant enzymes glutathione peroxidase 4, ferroptosis suppressor protein 1, and guanosine triphosphate cyclohydrolase 1. Therefore, we hypothesized that 4-HNE metabolism is up-regulated in HCC. A database search was focused on the transcriptional regulation of aldo-keto reductases, alcohol dehydrogenases, and glutathione-S-transferases, which are the metabolic enzymes of 4-HNE, and seven candidate transcription factor genes were selected. Among the candidate genes, the knockdown of SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily a, member 4 (SMARCA4) increased 4-HNE accumulation. Immunohistochemical analysis revealed an inverse correlation between 4-HNE accumulation and SMARCA4 expression. These results suggest that SMARCA4 regulates 4-HNE metabolism in HCC. Therefore, targeting SMARCA4 provides a basis for a new therapeutic strategy for HCC via 4-HNE accumulation and increased cytotoxicity.

3.
J Cell Sci ; 136(15)2023 08 01.
Article in English | MEDLINE | ID: mdl-37439249

ABSTRACT

The non-receptor tyrosine kinase SRC is overexpressed and/or hyperactivated in various human cancers, and facilitates cancer progression by promoting invasion and metastasis. However, the mechanisms underlying SRC upregulation are poorly understood. In this study, we demonstrate that transforming growth factor-ß (TGF-ß) induces SRC expression at the transcriptional level by activating an intragenic the SRC enhancer. In the human breast epithelial cell line MCF10A, TGF-ß1 stimulation upregulated one of the SRC promotors, the 1A promoter, resulting in increased SRC mRNA and protein levels. Chromatin immunoprecipitation (ChIP)-sequencing analysis revealed that the SMAD complex is recruited to three enhancer regions ∼15 kb upstream and downstream of the SRC promoter, and one of them is capable of activating the SRC promoter in response to TGF-ß. JUN, a member of the activator protein (AP)-1 family, localises to the enhancer and regulates TGF-ß-induced SRC expression. Furthermore, TGF-ß-induced SRC upregulation plays a crucial role in epithelial-mesenchymal transition (EMT)-associated cell migration by activating the SRC-focal adhesion kinase (FAK) circuit. Overall, these results suggest that TGF-ß-induced SRC upregulation promotes cancer cell invasion and metastasis in a subset of human malignancies.


Subject(s)
Epithelial-Mesenchymal Transition , Transforming Growth Factor beta , Humans , Transforming Growth Factor beta/metabolism , Epithelial-Mesenchymal Transition/genetics , Transforming Growth Factor beta1/pharmacology , Transforming Growth Factor beta1/metabolism , Cell Line , Focal Adhesion Protein-Tyrosine Kinases , Cell Movement/physiology , Cell Line, Tumor
4.
J Cell Physiol ; 238(4): 790-812, 2023 04.
Article in English | MEDLINE | ID: mdl-36791282

ABSTRACT

The liver kinase B1 (LKB1) controls cellular metabolism and cell polarity across species. We previously established a mechanism for negative regulation of transforming growth factor ß (TGFß) signaling by LKB1. The impact of this mechanism in the context of epithelial polarity and morphogenesis remains unknown. After demonstrating that human mammary tissue expresses robust LKB1 protein levels, whereas invasive breast cancer exhibits significantly reduced LKB1 levels, we focused on mammary morphogenesis studies in three dimensional (3D) acinar organoids. CRISPR/Cas9-introduced loss-of-function mutations of STK11 (LKB1) led to profound defects in the formation of 3D organoids, resulting in amorphous outgrowth and loss of rotation of young organoids embedded in matrigel. This defect was associated with an enhanced signaling by TGFß, including TGFß auto-induction and induction of transcription factors that mediate epithelial-mesenchymal transition (EMT). Protein marker analysis confirmed a more efficient EMT response to TGFß signaling in LKB1 knockout cells. Accordingly, chemical inhibition of the TGFß type I receptor kinase largely restored the morphogenetic defect of LKB1 knockout cells. Similarly, chemical inhibition of the bone morphogenetic protein pathway or the TANK-binding kinase 1, or genetic silencing of the EMT factor SNAI1, partially restored the LKB1 knockout defect. Thus, LKB1 sustains mammary epithelial morphogenesis by limiting pathways that promote EMT. The observed downregulation of LKB1 expression in breast cancer is therefore predicted to associate with enhanced EMT induced by SNAI1 and TGFß family members.


Subject(s)
Breast , Epithelial-Mesenchymal Transition , Morphogenesis , Organoids , Female , Humans , Epithelial Cells/metabolism , Liver/metabolism , Transforming Growth Factor beta/metabolism , Cell Line , Breast/cytology , Breast/growth & development
5.
J Appl Microbiol ; 134(1)2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36626746

ABSTRACT

Aurantiochytrium limacinum can accumulate high amounts of omega-3 polyunsaturated fatty acids, especially docosahexaenoic acid (DHA). Although salinity affects the DHA content, its impact on the metabolic pathway responsible for DHA production in A. limacinum is not completely understood. To address this issue, we investigated the transcriptional profile of A. limacinum under hypoosmotic stress. We first cultured A. limacinum under typical and low salinity for RNA sequencing, respectively. Transcriptome analyses revealed that 933 genes exhibited significant changes in expression under hypoosmotic conditions, of which 81.4% were downregulated. Strikingly, A. limacinum downregulated genes related to polyketide synthesis and fatty acid synthase pathways, while upregulating ß-oxidation-related genes. In accordance with this, DHA production significantly decreased under hypoosmotic conditions, while antioxidant-related genes were significantly upregulated. Considering that ß-oxidation of fatty acids generates energy and reactive oxygen species (ROS), our results suggest that A. limacinum utilizes fatty acids for energy to survive under hypoosmotic conditions and detoxifies ROS using antioxidant systems.


Subject(s)
Antioxidants , Fatty Acids, Omega-3 , Reactive Oxygen Species , Docosahexaenoic Acids/metabolism , Fatty Acids , Gene Expression Profiling , Sodium Chloride
6.
Appl Biochem Biotechnol ; 195(2): 1255-1267, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36346562

ABSTRACT

Aurantiochytrium limacinum is a heterotrophic eukaryotic microorganism that can accumulate high levels of commercial products such as astaxanthin and docosahexaenoic acid. Due to its rapid growth and relatively simple extraction method, A. limacinum is considered a promising astaxanthin resource to replace the conventional microalgal production. However, the astaxanthin biosynthetic process in A. limacinum remains incompletely understood, especially in those catalysed by ß-carotene hydroxylase (CrtZ) and ketolase. In this study, we overexpressed a crtZ candidate gene to increase astaxanthin production and expand our understanding of the conversion from beta-carotene to astaxanthin. The resultant transformant AlcrtZ#10 cultivated for 5 days showed a significant increase in astaxanthin production per culture (2.8-fold) and per cell (4.5-fold) compared with that of the wild-type strain. Strikingly, longer light exposure increased astaxanthin production and decreased the beta-carotene content in the wild-type strain, suggesting that light exposure duration is important for astaxanthin production in A. limacinum. Among several predicted intermediates, furthermore, the cantaxanthin produced from ß-carotene by ketolase activity were enhanced in the transformant AlcrtZ#10. Although the further investigation is needed, this result suggested that the main route of astaxanthin was via cantaxanthin. Thus, our findings will be valuable not only for its application, but also for understanding the astaxanthin biosynthetic process in A. limacinum.


Subject(s)
Oxygenases , beta Carotene , Oxygenases/genetics , Mixed Function Oxygenases/genetics
7.
Endocr J ; 70(1): 43-46, 2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36171143

ABSTRACT

Adrenal incidentaloma is a clinically unapparent adrenal mass more than one cm in diameter detected during imaging performed not for adrenal disease. A 34-year-old man was evaluated for AI with a diameter of 3.5 cm in the left adrenal. He was obese with body mass index of 33,9. Blood pressure was 110-120/90 mmHg. The general laboratory tests were unremarkable. An adrenal hormone screening set revealed that ACTH was 6.9 pg/mL, cortisol 14.9 µg/dL, renin activity 0.9 ng/mL/h, aldosterone 79.4 pg/mL, dehydroepiandrosterone-sulfate (DHEA-S) measured on two occasions 5,217 ng/mL and 6,477 ng/mL (gender- and age-adjusted reference values, 1,060-4,640 ng/mL). The levels of metanephrine and normetanephrine were normal. The tumor was thought to produce solely DHEA-S. The excised left adrenal tissue contained a tumor with a diameter of 26 mm and neighboring adrenal tissue. The tumor consisted mostly of acidophil cells without necrosis, capsular or vascular invasion, and mitosis. Immunohistochemical study revealed followings: the cells of the tumors were stained positive for 3ß-hydroxysteroid dehydrogenase, and 17α-hydroxylase, and 11ß-hydroxylase, weakly positive for DHEA sulphotransferase, and negative for aldosterone synthetase. The atrophy of neighboring tissue was presumably caused by excess cortisol production. Four months after surgery, the cortisol level was 11.2 µg/dL and DHEA-S level 1,462 ng/mL. The tumor is considered to be a cortisol-producing adenoma with modestly excessive DHEA-S production rather than isolated DHEA-S-producing adenoma. Immunohistochemical study of steroidogenic enzymes is a valuable addition to blood hormone measurement to clarify steroid production profile.


Subject(s)
Adenoma , Adrenal Gland Neoplasms , Male , Humans , Adult , Dehydroepiandrosterone Sulfate , Hydrocortisone , Aldosterone , Adrenal Gland Neoplasms/diagnosis , Adenoma/pathology , Mixed Function Oxygenases , Sulfates , Dehydroepiandrosterone
8.
J Appl Microbiol ; 132(6): 4330-4337, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35279928

ABSTRACT

AIMS: Astaxanthin-producing protist Aurantiochytrium limacinum can accumulate higher amounts of astaxanthin under light conditions; however, little is known about the impact of light exposure on its metabolism. Here, we investigated the transcriptional profile of A. limacinum under light conditions. METHODS AND RESULTS: Transcriptomic analyses revealed that 962 genes of A. limacinum showed a significant change in expression under light conditions, most of which (94.5%) were downregulated. Furthermore, gene ontology enrichment analysis indicated that A. limacinum mainly downregulated genes associated with cell motility, proliferation and gene expression processes, whose activities depend on ATP as an energy source. Additionally, the quantification of carotenoid and its transcripts suggested that ß-carotene and astaxanthin biosynthesis pathways were rate-limiting and tightly regulated steps, respectively. In comparison, these processes were enhanced under light conditions. CONCLUSIONS: Considering that astaxanthin accumulation was highly correlated with reactive oxygen species (ROS) levels in microalgae, our results suggest that A. limacinum reduces ATP consumption to decrease the occurrence of ROS in mitochondria while accumulating astaxanthin to prevent ROS damage. SIGNIFICANCE AND IMPACT OF STUDY: This study provides novel insights into the impact of light exposure on A. limacinum metabolism, thereby facilitating a complete understanding of this protist for efficient astaxanthin production.


Subject(s)
Microalgae , Stramenopiles , Adenosine Triphosphate/metabolism , Gene Expression Profiling , Microalgae/genetics , Reactive Oxygen Species/metabolism , Stramenopiles/genetics , Stramenopiles/metabolism
9.
Hum Mol Genet ; 31(13): 2194-2206, 2022 07 07.
Article in English | MEDLINE | ID: mdl-35103281

ABSTRACT

Age-related macular degeneration (AMD) and central serous chorioretinopathy (CSC) are common diseases that can cause vision loss in older and younger populations. These diseases share pathophysiological conditions derived from retinal pigment epithelium (RPE) dysfunction. Tumor necrosis factor receptor superfamily 10A (TNFRSF10A)-LOC389641 with the same lead single-nucleotide polymorphism (SNP) (rs13278062) is the only overlapped susceptibility locus found in both AMD and CSC through genome-wide association studies. This lead SNP has been reported to alter the transcriptional activity of TNFRSF10A. This study aimed to elucidate the function of TNFRSF10A in RPE degeneration using human primary RPE cells and Tnfrsf10 knockout (Tnfrsf10-/-) mice. TNFRSF10A was found to be localized in human RPE. In vitro assays revealed that a T allele of rs13278062, the risk allele for AMD and CSC, downregulated TNFRSF10A transcription in RPE, leading to decreased cell viability and increased apoptosis through protein kinase C-α (PKCA) downregulation. Treatment with phorbol 12-myristate 13-acetate, a PKC activator, rescued the cell viability. Morphological RPE abnormality was found in the retina of Tnfrsf10-/- mice. Our data suggest that downregulation of TNFRSF10A expression inactivates PKCA signaling and causes cellular vulnerability of the RPE, which may contribute to the pathogenesis of AMD and CSC.


Subject(s)
Central Serous Chorioretinopathy , Macular Degeneration , Receptors, TNF-Related Apoptosis-Inducing Ligand/metabolism , Animals , Central Serous Chorioretinopathy/metabolism , Central Serous Chorioretinopathy/pathology , Down-Regulation/genetics , Genome-Wide Association Study , Macular Degeneration/pathology , Mice , Receptors, Tumor Necrosis Factor/metabolism , Retinal Pigment Epithelium/metabolism
10.
Biochem Biophys Rep ; 26: 100961, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33732902

ABSTRACT

In this study, we studied the effects of cortisol and cortisone on the age-related decrease in locomotion in the nematode Caenorhabditis elegans and on the tolerance to heat stress at 35 °C and to oxidative stress induced by the exposure to 0.1% H2O2. Changes in mRNA expression levels of C. elegans genes related to stress tolerance were also analyzed. Cortisol treatment restored nematode movement following heat stress and increased viability under oxidative stress, but also shortened worm lifespan. Cortisone, a cortisol precursor, also restored movement after heat stress. Additionally, cortisol treatment increased mRNA expression of the hsp-12.6 and sod-3 genes. Furthermore, cortisol treatment failed to restore movement of daf-16-deficient mutants after heat stress, whereas cortisone failed to restore the movement of dhs-30-deficient mutants after heat stress. In conclusion, the results suggested that cortisol promoted stress tolerance via DAF-16 but shortened the lifespan, whereas cortisone promoted stress tolerance via DHS-30.

11.
Appl Biochem Biotechnol ; 193(6): 1967-1978, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33528746

ABSTRACT

Chlamydomonas reinhardtii is a well-established microalgal model species with a shorter doubling time, which is a promising natural source for the efficient production of high-value carotenoids. In the microalgal carotenoid biosynthetic pathway, lycopene is converted either into ß-carotene by lycopene ß-cyclase or into α-carotene by lycopene ε-cyclase (LCYE) and lycopene ß-cyclase. In this study, we overexpressed the LCYE gene in C. reinhardtii to estimate its effect on lycopene metabolism and lutein production. Chlamydomonas transformants (CrLCYE#L1, #L5, and #L6) produced significantly increased amounts of lutein per culture (up to 2.6-fold) without a decrease in cell yields. Likewise, the expression levels of LCYE gene in transformants showed a significant increase compared with that of the wild-type strain. These results suggest that LCYE overexpression enhances the conversion of lycopene to α-carotene, which in turn improves lutein productivity. Interestingly, their ß-carotene productivity appeared to increase slightly rather than decrease. Considering that the inhibition of the lycopene cyclization steps often induces higher expression in genes upstream of metabolic branches, this result implies that the redirection from ß-carotene to α-carotene by LCYE overexpression might also enhance upstream gene expression, thereby leading to auxiliary ß-carotene production.


Subject(s)
Chlamydomonas reinhardtii/metabolism , Intramolecular Lyases/biosynthesis , Lycopene/metabolism , Plant Proteins/biosynthesis , Carotenoids/metabolism , Chlamydomonas reinhardtii/genetics , Intramolecular Lyases/genetics , beta Carotene/genetics , beta Carotene/metabolism
12.
Neuropsychopharmacol Rep ; 41(1): 56-64, 2021 03.
Article in English | MEDLINE | ID: mdl-33426813

ABSTRACT

AIMS: Electroconvulsive seizure (ECS) therapy is highly effective in the treatment of several psychiatric disorders, including depression. Past studies have shown that the rodent model of ECS reveals the activation of multiple brain regions including the hypothalamus, suggesting that this method of brain stimulation broadly regulates central neuronal function, which results in peripheral function. The ventromedial nucleus of the hypothalamus (VMH) plays an important role in feeding and energy homeostasis. Our previous study showed that ECS increases the expression of anorexigenic factors in the VMH and has an anorexigenic effect in a mouse model. Since the VMH is also suggested to play a critical role in the peripheral lipid metabolism of white adipose tissue (WAT), we hypothesized that ECS alters lipid metabolism via activation of the VMH. METHODS AND RESULTS: Here, we demonstrate that repeated ECS suppresses the fat mass of epididymal WAT and significantly increases the expression levels of lipolytic and brown adipose tissue markers such as Adrb3, Hsl/Lipe, and Ppargc1a. In the VMH, ECS increased the expression of multiple genes, notably Bdnf, Adcyap1, and Crhr2, which are not only anorexigenic factors but are also modulators of lipid metabolism. Furthermore, gold-thioglucose-induced hypothalamic lesions affecting the VMH abolished the effect of ECS on the WAT, indicating that hypothalamus activation is required for the phenotypic changes seen in the epididymal WAT. CONCLUSION: Our data demonstrates a new effect of ECS on the lipid metabolism of WAT via induction of hypothalamic activity involving the VMH.


Subject(s)
Adipose Tissue, White/metabolism , Electroshock , Gene Expression/genetics , Hypothalamus, Middle/metabolism , Lipid Metabolism/physiology , Lipolysis/genetics , Weight Gain/physiology , Animals , Behavior, Animal/physiology , Epididymis/metabolism , Hypothalamus, Middle/pathology , Locomotion/physiology , Male , Mice
13.
Appl Biochem Biotechnol ; 193(1): 52-64, 2021 Jan.
Article in English | MEDLINE | ID: mdl-32808245

ABSTRACT

Aurantiochytrium limacinum produces both docosahexaenoic acid (DHA) and astaxanthin, respectively. Organisms that produce these industrially important materials more efficiently than microalgae are currently needed. In this study, we overexpressed a putative homolog of CarS, which is involved in synthesizing the astaxanthin precursor, ß-carotene, in A. limacinum to increase carotenoid synthesis with the goal of obtaining strains that produce large amounts of both DHA and carotenoids. AlCarS transformants #1 and #18 produced significantly increased amounts of astaxanthin as assessed according to culture (up to 5.8-fold) and optical density (up to 9.3-fold). The improved astaxanthin production of these strains did not affect their DHA productivity. Additionally, their CarS expression levels were higher than those of the wild-type strain, suggesting that CarS overexpression enhanced ß-carotene production, which in turn improved astaxanthin productivity. Although cell yields were slightly decreased, these features will be valuable in health food, medical care, and animal feed fields.


Subject(s)
Docosahexaenoic Acids/biosynthesis , Stramenopiles , Stramenopiles/enzymology , Stramenopiles/genetics , Xanthophylls/metabolism
14.
PLoS One ; 15(10): e0241343, 2020.
Article in English | MEDLINE | ID: mdl-33112920

ABSTRACT

This study aims to investigate the changes in metamorphopsia after administering the treat-and-extend regimen of anti-vascular endothelial growth factor therapy for branch retinal vein occlusion-associated macular edema. We retrospectively examined 27 patients (27 eyes) with macula edema due to branch retinal vein occlusion who received intravitreal injections of anti-vascular endothelial growth factor agents using the treat-and-extend regimen for ≥18 months. We evaluated best-corrected visual acuity, central macular thickness, macular edema recurrence, and amount of metamorphopsia quantified by M-CHARTS. The best-corrected visual acuity (logarithm of minimum angle of resolution) and central macular thickness significantly improved at 18 months compared to baseline, the median value (interquartile range [IQR]), 0.30 (0.15-0.52) and 459 (373-542) µm at baseline, and 0 (-0.08-0.16) and 267 (232-306) µm at 18 months. The M-CHARTS score (the mean of vertical and horizontal scores) significantly decreased at 1, 6, and 12 months compared to baseline, but worsened at 18 month, the median value (IQR), 0.45 (0.250-0.925), 0.4 (0.15-0.70), 0.4 (0.150-0.625), 0.4 (0.225-0.550) and 0.45 (0.225-0.750) at baseline, 1 month, 6 months, 12 months and 18 months, respectively. The median cumulative number of macular edema recurrences was 2 (IQR, 0.5-3.0) at 18 months. Simple linear regression and multivariate analyses revealed that the change in the mean M-CHARTS score at 18 months was significantly correlated with the baseline score and the cumulative number of macular edema recurrences. Anti-vascular endothelial growth factor therapy using the treat-and-extend regimen improved metamorphopsia in branch retinal vein occlusion-related macular edema in the short to mid-term follow-up period, but not in the long term. Macular edema recurrence may be associated with persistent metamorphopsia.


Subject(s)
Angiogenesis Inhibitors/therapeutic use , Macular Edema/complications , Macular Edema/drug therapy , Retinal Vein Occlusion/complications , Retinal Vein Occlusion/drug therapy , Vascular Endothelial Growth Factor A/antagonists & inhibitors , Vision Disorders/complications , Aged , Angiogenesis Inhibitors/pharmacology , Female , Humans , Male , Middle Aged , Recurrence , Vascular Endothelial Growth Factor A/metabolism , Visual Acuity
15.
Sci Rep ; 10(1): 9299, 2020 06 09.
Article in English | MEDLINE | ID: mdl-32518264

ABSTRACT

Ischemic proliferative retinopathy (IPR), such as proliferative diabetic retinopathy (PDR), retinal vein occlusion and retinopathy of prematurity is a major cause of vision loss. Our previous studies demonstrated that periostin (PN) and tenascin-C (TNC) are involved in the pathogenesis of IPR. However, the interactive role of PN and TNC in angiogenesis associated with IPR remain unknown. We found significant correlation between concentrations of PN and TNC in PDR vitreous humor. mRNA and protein expression of PN and TNC were found in pre-retinal fibrovascular membranes excised from PDR patients. Interleukin-13 (IL-13) promoted mRNA and protein expression of PN and TNC, and co-immunoprecipitation assay revealed binding between PN and TNC in human microvascular endothelial cells (HRECs). IL-13 promoted angiogenic functions of HRECs. Single inhibition of PN or TNC and their dual inhibition by siRNA suppressed the up-regulated angiogenic functions. Pathological pre-retinal neovessels of oxygen-induced retinopathy (OIR) mice were attenuated in PN knock-out, TNC knock-out and dual knock-out mice compared to wild-type mice. Both in vitro and in vivo, PN inhibition had a stronger inhibitory effect on angiogenesis compared to TNC inhibition, and had a similar effect to dual inhibition of PN and TNC. Furthermore, PN knock-out mice showed scant TNC expression in pre-retinal neovessels of OIR retinas. Our findings suggest that interaction of PN and TNC facilitates pre-retinal angiogenesis, and PN is an effective therapeutic target for IPR such as PDR.


Subject(s)
Cell Adhesion Molecules/metabolism , Diabetic Retinopathy/pathology , Neovascularization, Pathologic/pathology , Retinal Vessels/growth & development , Tenascin/metabolism , Vitreoretinopathy, Proliferative/pathology , Aged , Animals , Cell Adhesion Molecules/genetics , Cells, Cultured , Endothelial Cells/metabolism , Female , Humans , Interleukin-13/metabolism , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Tenascin/genetics , Vitreous Body/metabolism
16.
J Am Chem Soc ; 142(16): 7699-7708, 2020 Apr 22.
Article in English | MEDLINE | ID: mdl-32212655

ABSTRACT

Controlled covalent functionalization of graphitic surfaces with molecular scale precision is crucial for tailored modulation of the chemical and physical properties of carbon materials. We herein present that porous self-assembled molecular networks (SAMNs) act as nanometer scale template for the covalent electrochemical functionalization of graphite using an aryldiazonium salt. Hexagonally aligned achiral grafted species with lateral periodicity of 2.3, 2.7, and 3.0 nm were achieved utilizing SAMNs having different pore-to-pore distances. The unit cell vectors of the grafted pattern match those of the SAMN. After the covalent grafting, the template SAMNs can be removed by simple washing with a common organic solvent. We briefly discuss the mechanism of the observed pattern transfer. The unit cell vectors of the grafted pattern align along nonsymmetry axes of graphite, leading to mirror image grafted domains, in accordance with the domain-specific chirality of the template. In the case in which a homochiral building block is used for SAMN formation, one of the 2D mirror image grafted patterns is canceled. This is the first example of a nearly crystalline one-sided or supratopic covalent chemical functionalization. In addition, the positional control imposed by the SAMN renders the functionalized surface (homo)chiral reaching a novel level of control for the functionalization of carbon surfaces, including surface-supported graphene.

17.
Mol Cell Biol ; 40(10)2020 04 28.
Article in English | MEDLINE | ID: mdl-32123008

ABSTRACT

Proteasomes are essential protease complexes that maintain cellular homeostasis, and aberrant proteasomal activity supports cancer development. The regulatory mechanisms and biological function of the ubiquitin-26S proteasome have been studied extensively, while those of the ubiquitin-independent 20S proteasome system remain obscure. Here, we show that the cap 'n' collar (CNC) family transcription factor NRF3 specifically enhances 20S proteasome assembly in cancer cells and that 20S proteasomes contribute to colorectal cancer development through ubiquitin-independent proteolysis of the tumor suppressor p53 and retinoblastoma (Rb) proteins. The NRF3 gene is highly expressed in many cancer tissues and cell lines and is important for cancer cell growth. In cancer cells, NRF3 upregulates the assembly of the 20S proteasome by directly inducing the gene expression of the 20S proteasome maturation protein POMP. Interestingly, NRF3 knockdown not only increases p53 and Rb protein levels but also increases p53 activities for tumor suppression, including cell cycle arrest and induction of apoptosis. Furthermore, protein stability and cell viability assays using two distinct proteasome inhibitor anticancer drugs, the 20S proteasome inhibitor bortezomib and the ubiquitin-activating enzyme E1 inhibitor TAK-243, show that the upregulation of the NRF3-POMP axis leads to ubiquitin-independent proteolysis of p53 and Rb and to impaired sensitivity to bortezomib but not TAK-243. More importantly, the NRF3-POMP axis supports tumorigenesis and metastasis, with higher NRF3/POMP expression levels correlating with poor prognoses in patients with colorectal or rectal adenocarcinoma. These results suggest that the NRF3-POMP-20S proteasome assembly axis is significant for cancer development via ubiquitin-independent proteolysis of tumor suppressor proteins.


Subject(s)
Basic-Leucine Zipper Transcription Factors/metabolism , Molecular Chaperones/metabolism , Neoplasms/metabolism , Proteasome Endopeptidase Complex/metabolism , Retinoblastoma Protein/metabolism , Tumor Suppressor Protein p53/metabolism , HCT116 Cells , HeLa Cells , Humans , Proteolysis , Ubiquitin/metabolism
18.
J Dermatol ; 46(5): 436-439, 2019 May.
Article in English | MEDLINE | ID: mdl-30768803

ABSTRACT

Pigmented Bowen's disease (pBD) is a subtype of Bowen's disease, which presents clinically as a well-circumscribed, hyperpigmented plaque. Its clinical manifestations are not fully characterized, and differential diagnoses include various pigmented skin lesions. Dermoscopy could be useful for the diagnosis, although nothing has been reported on the dermoscopic features of clonal-type pBD. We herein report a first case of clonal-type pBD on the sole and its dermoscopic features. Dermoscopy showed brown to blue-gray dots/globules and focally anastomosing lines on the non-weight-bearing area, while the weight-bearing area had a brown to blue-gray fibrillar-like pattern. To investigate the relationship between dermoscopy and histopathology, we focused on the melanin distribution in the horny layer of the epidermis, and used vertical dermoscopy observation. We investigated the relationship between dermoscopy and pathology by melanin depth estimation using a color lightness value.


Subject(s)
Bowen's Disease/diagnostic imaging , Dermoscopy/methods , Hyperpigmentation/diagnostic imaging , Skin Neoplasms/diagnostic imaging , Adult , Biopsy , Bowen's Disease/pathology , Diagnosis, Differential , Foot , Humans , Hyperpigmentation/pathology , Male , Melanins/analysis , Skin/diagnostic imaging , Skin/pathology , Skin Neoplasms/pathology
19.
Langmuir ; 35(6): 2089-2098, 2019 Feb 12.
Article in English | MEDLINE | ID: mdl-30626188

ABSTRACT

Grafting of aryl radicals generated by electrochemical reduction of aryldiazonium salts has been extensively studied on various surfaces. However, there exists two unclear aspects; the first one is the generality of the blocking ability of simple functional groups toward multilayer growth, and the second one is the electronic impact of substituent groups of aryl radicals on grafting efficiency. To address these aspects, we have studied the electrochemical functionalization of graphite using aryldiazonium salts having electron-donating or electron-withdrawing groups at the 3,4,5-positions. Atomic force microscopy investigation of the functionalized surfaces revealed the formation of monolayers for all aryldiazonium salts, and thus, nitro, carboxy, ester, methyl, and methoxy groups at the 3,4,5-positions of the benzene ring suppress polyaryl growth. The degree of grafting estimated by scanning tunneling microscopy imaging and Raman spectroscopy of the functionalized surfaces depends on the electronic state of the aryl radicals, in which the radicals with electron-donating groups show a high degree of functionalization, whereas those with electron-withdrawing groups exhibit a low degree of functionalization. We discuss several possibilities that affect grafting density. Though there are several factors, we hypothesize that one factor to explain the observed reactivity trend is the electronic property of the aryl radicals, namely, the relative position of the singly occupied molecular orbital energy levels of the aryl radicals with respect to the graphite Fermi energy level.

20.
ACS Nano ; 12(11): 11520-11528, 2018 Nov 27.
Article in English | MEDLINE | ID: mdl-30387985

ABSTRACT

An approach for nanoscale covalent functionalization of graphite surfaces employing self-assembled molecular monolayers of n-alkanes as templating masks is presented. Linearly aligned aryl groups with a lateral periodicity of 5 or 7 nm are demonstrated utilizing molecular templates of different lengths. The key feature of this approach is the use of a phase separated solution double layer consisting of a thin organic layer containing template molecules topped by an aqueous layer containing aryldiazonium molecules capable of electrochemical reduction to generate aryl radicals which bring about surface grafting. Upon sweeping of the potential, lateral displacement dynamics at the n-alkane terminal edges acts in conjunction with electrochemical diffusion to result in templated covalent bond formation in a linear fashion. This protocol was demonstrated to be applicable to linear grafting of graphene. The present processing described herein is useful for the realization of rationally designed nanoscale materials.

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