scholarly journals RASSF1A regulates the abnormal cell proliferation in psoriasis via inhibition of YAP

2020 ◽  
Author(s):  
Jinjing Jia ◽  
Ning Wang ◽  
Yan Zheng ◽  
Xiumei Mo ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Inflammatory Cytokines ◽  
Skin Lesions ◽  
Oncostatin M ◽  
Negative Regulator ◽  
Inflammatory Factors ◽  
Epidermal Keratinocytes ◽  
Lentivirus Vector ◽  
Rassf1a Methylation

Abstract Background: Psoriasis is a chronic, inflammatory skin disease with high incidence, treatment resistance, and high recurrence. Currently, the exact etiology and pathogenesis of psoriasis are unclear. The goal of this study was to characterize the effect of the upstream negative regulator RAS-association domain family 1A (RASSF1A) on Yes-associated protein (YAP) in psoriasis. Methods: Skin lesions of 22 patients with psoriasis and 19 controls with normal skin tissue were used. Human epidermal keratinocytes were stimulated with M5 (IL-1 α, IL-17, IL-22, TNF-α, oncostatin M) to establish the psoriatic cell model. Methylation inhibitor 5-Aza-CdR was prepared at different concentrations (5, 10, 20 μmol/L). Cells were infected with lentivirus vector overexpressing RASSF1A. Twenty-five 6–8-week-old female BALB/c mice were used to establish the psoriatic mouse model. Mice were randomly divided into five groups: control (Vaseline applied daily), psoriasis (imiquimod applied daily), and the three different 5-Aza-CdR concentrations (applied daily with imiquimod). Methylation-specific PCR (MSP) was used to detect RASSF1A methylation and immunohistochemistry was used to detect RASSF1A expression in skin lesions. After adding 5-Aza-CdR or lentivirus vector overexpressing RASSF1A, YAP expression, cell proliferation, cell cycle, apoptosis, inflammatory cytokines, and related signal pathway activity were investigated. Results: As RASSF1A methylation level increased, its expression in patients with psoriasis and mice with skin lesions decreased. Addition of 5-Aza-CdR or lentivirus vector overexpressing RASSF1A increased the expression of RASSF1A, reduced the expression of YAP and inflammatory cytokines, cell proliferation, as well as AKT, ERK, STAT3, and NF-κB signaling pathway activities, induced cell cycle arrest in G0/G1 phase, increased apoptosis, and improved skin lesions. Conclusions: RASSF1A inhibited the proliferation of psoriatic cells, induced apoptosis, and reduced the expression of inflammatory factors by inhibiting YAP expression. Based on our findings, targeted drugs that can inhibit RASSF1A methylation and increase its expression may be useful in the treatment of psoriasis.

scholarly journals RASSF1A Regulates the Abnormal Cell Proliferation in Psoriasis via Inhibition of YAP

2020 ◽  
Author(s):  
Jinjing Jia ◽  
Ning Wang ◽  
Yan Zheng ◽  
Xiumei Mo ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Inflammatory Cytokines ◽  
Skin Lesions ◽  
Oncostatin M ◽  
Negative Regulator ◽  
Inflammatory Factors ◽  
Epidermal Keratinocytes ◽  
Lentivirus Vector ◽  
Rassf1a Methylation

Abstract Background: Psoriasis is a chronic, inflammatory skin disease with high incidence, treatment resistance, and high recurrence. Currently, the exact etiology and pathogenesis are unclear. The goal of this study was to characterize the role of the upstream negative regulator RAS-association domain family 1A (RASSF1A) on Yes-associated protein (YAP) in psoriasis.Methods: Skin lesions of 22 psoriasis patients and 19 normal skin tissue controls were used. Human epidermal keratinocytes were stimulated with M5 (IL-1 α, IL-17, IL-22, TNF-α, oncostatin M), to establish the psoriatic cell model. Methylation inhibitor, 5-Aza-CdR was prepared at different concentrations (5, 10, 20 μmol/L). Cells were infected with lentivirus vector overexpressing RASSF1A. Twenty-five 6-8-week-old female BALB/c mice were used to establish the psoriatic mouse model. Mice were randomly divided into five groups: control (Vaseline applied daily), psoriasis (imiquimod applied daily), and the three different 5-Aza-CdR concentrations (applied daily with imiquimod). Methylation specific PCR (MSP) was used to detect RASSF1A methylation, and immunohistochemistry was used to detect RASSF1A expression in skin lesions. After adding 5-Aza-CdR or lentivirus vector overexpressing RASSF1A, YAP expression, cell proliferation, cell cycle, apoptosis, inflammatory cytokines and related signal pathway activity were detected.Results: As RASSF1A methylation level increased, its expression in psoriasis patients and mice with skin lesions decreased. Addition of 5-Aza-CdR or lentivirus vector overexpressing RASSF1A increased the expression of RASSF1A, reduced the expression of YAP and inflammatory cytokines, cell proliferation, as well as AKT, ERK, STAT3 and NF-κB signaling pathway activities, induced cell cycle arrest in G0/G1 phase, increased apoptosis, and improved skin lesions.Conclusions: RASSF1A inhibited the proliferation of psoriatic cells, induced apoptosis, and reduced the expression of inflammatory factors by inhibiting YAP expression. Based on our findings, targeted drugs that can inhibit RASSF1A methylation and increase its expression may be useful in the treatment of psoriasis.

scholarly journals Topical Treatment of Colquhounia Root Relieves Skin Inflammation and Itch in Imiquimod-Induced Psoriasiform Dermatitis in Mice

2022 ◽  
Vol 2022 ◽  
pp. 1-15
Author(s):  
Fei Li ◽  
Dan Han ◽  
Bo Wang ◽  
Wentao Zhang ◽  
Yan Zhao ◽  
...  
Keyword(s):  
Inflammatory Cytokines ◽  
Neurogenic Inflammation ◽  
Chinese Herb ◽  
Clinical Manifestations ◽  
Skin Lesions ◽  
Oncostatin M ◽  
Inflammatory Factors ◽  
Epidermal Keratinocytes ◽  
Human Epidermal Keratinocytes

Itch is one of the major clinical manifestations of psoriasis, which is closely related with neurogenic inflammation and difficult to control. Colquhounia Root (CR) is a Chinese herb exhibiting broad bioactivities on anti-inflammation. This study was designed to explore the antipsoriatic and anti-itch potential of CR and its underlying mechanisms. Mice in a model of imiquimod-induced psoriasiform dermatitis were treated topically with CR for 7 days, and the severity of skin lesions and itch was significantly ameliorated. CR reduced the inflammatory cell infiltration, as well as mast cells in skins. Particularly, the expression of inflammatory cytokines and chemokine including Il17a, Il22, and Ccl20 and itch-related molecules such as SP, CGRP, and NGF in lesions were decreased in diseased mice upon application with CR. The normal human epidermal keratinocytes were stimulated with the M5 cytokine cocktail, the mixture of IL-17A, IL-22, Oncostatin M, IL-1α, and TNF-α, and cell viability and mRNA expression levels of inflammatory factors and itch-related molecules were measured after being treated with CR. We found that CR inhibited both cell hyperproliferation and overexpression of inflammatory cytokines and itch-related molecules in vitro. Altogether, we conclude that CR relieves psoriatic lesions and itch via controlling immunological and neurogenic inflammation.

Crucial Factors of the Inflammatory Microenvironment (IL-1 beta/TNF-alpha/TIMP-1) Promote Maintenance of the Malignant Hemopoietic Clone of Myelofibrosis By Stimulating the in Vitro Survival/Proliferation/Migration of Circulating CD34+ stem/Progenitor Cells

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 4094-4094
Author(s):  
Dorian Forte ◽  
Daria Sollazzo ◽  
Nicola Polverelli ◽  
Romano Marco ◽  
Lara Rossi ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Inflammatory Cytokines ◽  
Stromal Cells ◽  
Colony Formation ◽  
Inflammatory Factors ◽  
Inflammatory Microenvironment ◽  
Cd34 Cells ◽  
Tnf Α ◽  
Pro Inflammatory Cytokines

Abstract Introduction. Myelofibrosis (MF), an acquired clonal disorder of the hematopoietic stem/progenitor cell (HSPC) with a dysregulation in JAK/STAT signalling (mutations in JAK2, MPL and Calreticulin (CALR) genes), is characterized by a state of chronic inflammation. It is argued that the up-regulated production of proinflammatory cytokines by both HSPCs and the surrounding stromal cells generates a microenvironment that selects for the malignant clone. Only recently, it has been hypothesized that the sustained inflammatory microenvironment of MF can alter crucial biological processes, leading to genomic instability and cancer progression. Here we tested the in vitro functional effects of pivotal players of the inflammatory microenvironment (the extracellular ATP nucleotide and selected cytokines, such as Interleukin (IL)-1β, Tumor Necrosis Factor (TNF)-α or the Tissue Inhibitor of Metalloproteinases-1 (TIMP-1)) on the HSPCs from MF patients. Methods: Circulating CD34+/CD34+ CD38- cells from MF patients (JAK2V617F (17 cases) and CALR (9 cases) mutations) or cord blood (CB; 8 samples) were phenotypically and functionally characterized after in vitro incubation with or without ATP (1000 μM), IL-1β (10 ng/mL), TNF-α (10 ng/mL) or TIMP-1 (100 ng/mL) (alone or in combination). Cells were then analyzed for survival/apoptosis (Annexin-V/Propidium Iodide staining), phenotype (evaluation of CD63 (TIMP-1 receptor), CXCR4 and CD38 expression), cell cycle and clonogenic capacity. Migration was assessed first towards a CXCL12 gradient in the presence or absence of the pro-inflammatory factors. In parallel experiments, CD34+ cells from MF patients were co-cultured with normal mesenchymal stromal cells (MSCs) in the presence or absence of the pro-inflammatory cytokines and then evaluated for their ability to migrate towards a CXCL12 gradient. Plasma TIMP-1, TNF-α, IL-1β and CXCL12 were measured by ELISA assay. Results: The plasma levels of TIMP-1, TNF-α, IL-1β, CXCL12 and the number of circulating CD34+, CD34+ CD38-, CD34+ CD63+, CD34+ CD184+ cells were increased in MF patients. According to mutational status, the CD34+ CD63+ cells were higher in the CALR+ patients. The survival of MF CD34+ cells was strongly stimulated by in vitro incubation with TNF-α or IL-1β as compared with the CB-derived CD34+ cells or untreated cells. By multiple cytokine combinations, IL-1β/TIMP-1, IL-1β /ATP or IL-1β /TNF-α treatments significantly promote the survival of MF CD34+ cells as compared with the normal counterparts or the untreated cells. Various combinations with IL-1β were also effective in stimulating survival of CD34+CD38- cells. IL-1β/TIMP-1 and IL-1β/TNF-α/TIMP-1, but not factors alone, significantly increased the CFU-C growth of MF patients as compared with the CB-derived counterparts and the untreated cells. Moreover, comparing CALR+ vs JAK2V617F+ patients, the colony formation of JAK2V617F+ patients was mainly promoted by the IL-1β/TNF-α treatment. Along with clonogenic capacity stimulation, exposure of CD34+ cells from MF patients to IL-1β/TNF-α/TIMP-1 significantly increases the S-phase cells, suggesting that these pro-inflammatory factors stimulated cell-cycle progression in dormant CD34+ MF cells. Migration of CD34+ cells from MF was significantly increased in CXCL12 treated cells. In addition, exposure of MF CD34+ cells to IL-1β/TNF-α, IL-1β/TIMP-1 or IL-1β/TNF-α/TIMP-1 significantly promotes cell migration in comparison with the CB-derived counterparts or SDF-1 alone. MF migrated cells in the presence of IL-1β/TNF-α significantly upregulate CD63 expression. Intriguingly, colony formation of MF migrated CD34+ cells in the presence of IL-1β/TNF-α or IL-1β/TNF-α/TIMP-1 was potently increased. Finally, co-culture systems with normal MSCs in the presence of pro-inflammatory factors revealed that MF CD34+ cells display increased migration ability toward CXCL12 gradient. Conclusions: Altogether our findings suggest that in MF the inflammatory niche plays a key role in the maintenance of the malignant clone. Thus, the interplay between the pro-inflammatory cytokines promote and select the HSPCs with higher proliferative activity, clonogenic potential and migration capability. Targeting these microenvironmental interactions may be a clinically relevant approach. D.F. and D.S. equally contributed Disclosures Martinelli: Pfizer: Consultancy; Ariad: Consultancy; Novartis: Consultancy, Speakers Bureau; MSD: Consultancy; AMGEN: Consultancy; BMS: Consultancy, Speakers Bureau; ROCHE: Consultancy.

scholarly journals Cyclin G1 inhibits the proliferation of mouse endometrial stromal cell in decidualization

2017 ◽  
Vol 69 (1) ◽  
pp. 71-81
Author(s):  
Qian Xu ◽  
Dong-zhi Yuan ◽  
Sheng Zhang ◽  
Ting Qu ◽  
Shi-mao Zhang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Stromal Cells ◽  
Stromal Cell ◽  
Embryo Implantation ◽  
Negative Regulator ◽  
Cell Cycle Regulators ◽  
Cyclin G1 ◽  
Decidual Cells

Uterine stromal cell decidualization is a dynamic physiological process in which cell proliferation, differentiation and apoptosis are orchestrated and occur in a temporal and cell-specific manner. This process is important for successful embryo implantation. Many cell-cycle regulators are involved in decidualization. The protein cyclin G1 is a unique regulator of the cell cycle with dual functions in cell proliferation. It was reported that cyclin G1 is expressed in mouse uterine stromal cells during the period of peri-implantation. To prove the function of cyclin G1 in mouse uterine stromal cells during this period, immunohistochemistry was used to stain mouse uterine tissues on days 4-8 of pregnancy. The results showed obvious spatial and temporal expression of cyclin G1 in uterine stromal cells, and that it is expressed in the cells of the primary decidual zone (PDZ) on day 5 and secondary decidual zone (SDZ) on days 6 and 7, when the stromal cells experienced active proliferation and differentiation was initiated. Applying the decidualization model of cultured primary stromal cells in vitro, we further revealed that the expression of cyclin G1 is associated with decidualization of stromal cells induced by medroxyprogesterone acetate (MPA) and estradiol-17? (E2). RNA interference was used for the knockdown of cyclin G1 in the induced decidual cells. Flow cytometry analysis indicated that the proportion of cells in the S stage was increased, and decreased in the G2/M phase. Our study indicates that cyclin G1, as a negative regulator of the cell cycle, plays an important role in the process of decidualization in mouse uterine stromal cells by inhibiting cell-cycle progression.

scholarly journals MicroRNA-322 inhibits inflammatory cytokine expression and promotes cell proliferation in LPS-stimulated murine macrophages by targeting NF-κB1 (p50)

2017 ◽  
Vol 37 (1) ◽  
Author(s):  
Kai Zhang ◽  
Fengling Song ◽  
Xiaoxia Lu ◽  
Wenxun Chen ◽  
Chunxiao Huang ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Inflammatory Response ◽  
Inflammatory Cytokines ◽  
Cell Cycle Progression ◽  
Negative Regulator ◽  
Luciferase Assay ◽  
Raw264.7 Cells ◽  
Expression Levels ◽  
Pathogen Invasion ◽  
Lps Treatment

Inflammation is the body’s normal self-protection mechanism to eliminate pathogens and resist pathogen invasion. The excessive inflammatory response may lead to inflammatory lesions. The mechanisms accounting for inflammation remain hazy. miRNAs have been proposed to have crucial effects on inflammation. In the present study, we reported that lipopolysaccharide (LPS)-stimulation increased the expression levels of inflammatory cytokines and the cell-cycle progression was suppressed in RAW264.7 cells. Meanwhile, the expression of miR-322 was significantly down-regulated after LPS treatment. Bioinformatics predictions revealed a potential binding site of miR-322 in 3′-UTR of NF-κB1 (p50) and it was further confirmed by luciferase assay. Moreover, both the mRNA and protein levels of NF-κB1 (p50) were down-regulated by miR-322 in RAW264.7 cells. Subsequently, we demonstrated that miR-322 mimics decrease in the expression levels of inflammatory cytokines and cell-cycle repression can be rescued following LPS treatment in RAW264.7 cells. The anti-inflammatory cytokines expression including IL-4 and IL-10 were significantly up-regulated. Furthermore, miR-322 could also promote RAW264.7 cells proliferation. These results demonstrate that miR-322 is a negative regulator of inflammatory response by targeting NF-κB1 (p50).

scholarly journals AdipoR2 inhibits human glioblastoma cell growth through the AMPK/mTOR pathway

2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Chen Jie ◽  
Wang Xuan ◽  
Han-Dong Feng ◽  
Ding-Mao Hua ◽  
Wang Bo ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Cell Proliferation ◽  
Cell Cycle Arrest ◽  
Cell Line ◽  
Expression Profiles ◽  
Mtor Pathway ◽  
Negative Regulator ◽  
Cycle Arrest ◽  
U251 Cells

Abstract Background AdipoR2, which belongs to the seven-transmembrane-domain receptor family, has been shown to play an important role in the development of human tumours, but the underlying mechanisms are poorly understood. In this study, we found that AdipoR2 expression correlates with glioma grade. In addition, we also investigated the mechanisms behind the antiproliferative effects of AdipoR2 in U251 cells (a human glioma cell line) using colony formation and WST-8 growth assays. Methods The U251 cell line was cultured in vitro. Western blotting was used to detect the expression of relevant proteins. Quantitative RT-PCR was used to detect AdipoR1 and AdipoR2 expression. Flow cytometry was used to detect cell cycle assay results. The gene expression profiles of glioma samples from the CGGA database were analysed by MATLAB and GSEA software. Results The AMPK/mTOR pathway plays a central role in the regulation of cell proliferation, differentiation and migration and may promote tumorigenesis. Therefore, we can control cancer progression by modulating the AMPK/mTOR pathway. However, there is no information on the relationship between AdipoR and AMPK/mTOR in central nervous system tumours such as GBM. In this study. We found 648 upregulated genes and 436 downregulated genes correlated with AdipoR2 expression in 158 glioma samples. GSEA suggested that AdipoR2 is a cell cycle-associated gene. The results of the flow cytometry analysis indicated that AdipoR2 induced G0/G1 cell cycle arrest in U251 cells. Furthermore, we identified the AMPK/mTOR signalling axis to be involved in AdipoR2-induced cell cycle arrest. Conclusions Our results suggest that AdipoR2 may represent a novel endogenous negative regulator of GBM cell proliferation. These findings also suggest that AdipoR2 may be a promising therapeutic target in GBM patients.

scholarly journals Marine Fungal Cerebroside Flavuside B Protects HaCaT Keratinocytes against Staphylococcus aureus Induced Damage

Marine Drugs ◽  
2021 ◽  
Vol 19 (10) ◽  
pp. 553
Author(s):  
Ekaterina A. Chingizova ◽  
Ekaterina S. Menchinskaya ◽  
Artur R. Chingizov ◽  
Evgeny A. Pislyagin ◽  
Elena V. Girich ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Staphylococcus Aureus ◽  
Skin Lesions ◽  
Epidermal Keratinocytes ◽  
Negative Consequences ◽  
Human Epidermal Keratinocytes ◽  
In Vivo Experiments ◽  
Dual Action ◽  
Anti Inflammatory

Cerebrosides are glycosylated sphingolipids, and in mammals they contribute to the pro-/anti-inflammatory properties and innate antimicrobial activity of the skin and mucosal surfaces. Staphylococcus aureus infection can develop, not only from minor scratches of the skin, but this pathogen can also actively promote epithelial breach. The effect of cerebroside flavuside B from marine sediment-derived fungus Penicillium islandicum (Aniva Bay, the Sea of Okhotsk) on viability, apoptosis, total caspase activity, and cell cycle in human epidermal keratinocytes HaCaT line co-cultivated with S. aureus, as well as influence of flavuside B on LPS-treated HaCaT cells were studied. Influence of flavuside B on bacterial growth and biofilm formation of S. aureus and its effect on the enzymatic activity of sortase A was also investigated. It was found S. aureus co-cultivated with keratinocytes induces caspase-depended apoptosis and cell death, arrest cell cycle in the G0/G1 phase, and increases in cellular immune inflammation. Cerebroside flavuside B has demonstrated its antimicrobial and anti-inflammatory properties, substantially eliminating all the negative consequences caused by co-cultivation of keratinocytes with S. aureus or bacterial LPS. The dual action of flavuside B may be highly effective in the treatment of bacterial skin lesions and will be studied in the future in in vivo experiments.

scholarly journals The multi-subunit GID/CTLH E3 ubiquitin ligase promotes cell proliferation and targets the transcription factor Hbp1 for degradation

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Fabienne Lampert ◽  
Diana Stafa ◽  
Algera Goga ◽  
Martin Varis Soste ◽  
Samuel Gilberto ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Proliferation ◽  
Ubiquitin Ligase ◽  
E3 Ubiquitin Ligase ◽  
Hierarchical Organization ◽  
Negative Regulator ◽  
Cell Cycle Exit ◽  
Cellular Analysis ◽  
Ubiquitin Ligase Activity

In yeast, the glucose-induced degradation-deficient (GID) E3 ligase selectively degrades superfluous gluconeogenic enzymes. Here, we identified all subunits of the mammalian GID/CTLH complex and provide a comprehensive map of its hierarchical organization and step-wise assembly. Biochemical reconstitution demonstrates that the mammalian complex possesses inherent E3 ubiquitin ligase activity, using Ube2H as its cognate E2. Deletions of multiple GID subunits compromise cell proliferation, and this defect is accompanied by deregulation of critical cell cycle markers such as the retinoblastoma (Rb) tumor suppressor, phospho-Histone H3 and Cyclin A. We identify the negative regulator of pro-proliferative genes Hbp1 as a bonafide GID/CTLH proteolytic substrate. Indeed, Hbp1 accumulates in cells lacking GID/CTLH activity, and Hbp1 physically interacts and is ubiquitinated in vitro by reconstituted GID/CTLH complexes. Our biochemical and cellular analysis thus demonstrates that the GID/CTLH complex prevents cell cycle exit in G1, at least in part by degrading Hbp1.

scholarly journals FBW7 Regulates the Autophagy Signal in Mesangial Cells Induced by High Glucose

2019 ◽  
Vol 2019 ◽  
pp. 1-9
Author(s):  
Chenlin Gao ◽  
Fang Fan ◽  
Jiao Chen ◽  
Yang Long ◽  
Shi Tang ◽  
...  
Keyword(s):  
Diabetic Nephropathy ◽  
Inflammatory Cytokines ◽  
High Glucose ◽  
Mesangial Cells ◽  
Negative Regulator ◽  
Inflammatory Factors ◽  
Gene Overexpression ◽  
F Box Protein ◽  
The Relationship

Aims. Abnormal regulation of autophagy participates in the development of diabetic nephropathy. mTOR is the most common negative regulator of the autophagy signaling pathway. FBW7 constitutes the SCF (Skp1–Cullin1–F-box protein) recognition subunit of E3 ubiquitin ligase, and mTOR is a substrate of FBW7 that can be modified by ubiquitination and be degraded via proteasomes. In this study, we explored the relationship between FBW7 and autophagy and examined the effects of FBW7 on the occurrence of diabetic nephropathy in vitro.Materials and Methods. We cultured mesangial cells induced by high glucose in vitro and used rapamycin as a specific mTOR inhibitor, performed FBW7 gene overexpression, and detected the expression of autophagy signal and inflammatory factors by WB, ELISA, RT-PCR, and immunofluorescence.Results. High glucose can downregulate the expression of FBW7 and activate mTOR signal, which leads to diminished autophagy in renal mesangial cells, as well as renal inflammatory cytokines and fibrotic factors. RAPA, as a specifically inhibitor of mTOR, can decrease inflammatory cytokines and fibrotic factors by inhibiting mTOR. Moreover, FBW7 gene overexpression can increase autophagy by inhibiting mTOR signal; at the same time, the inflammatory cytokines and fibrotic factors were decreased in mesangial cells.Conclusions. FBW7 was decreased in renal mesangial cells induced by high glucose, and FBW7 gene overexpression can increase autophagy by inhibiting mTOR signaling and ameliorate inflammation and fibrosis.

scholarly journals Ribosomal L1 domain-containing protein 1 coordinates with HDM2 to negatively regulate p53 in human colorectal Cancer cells

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Li Ding ◽  
Zhiping Zhang ◽  
Chenhong Zhao ◽  
Lei Chen ◽  
Zhiqiang Chen ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cell Cycle ◽  
Cell Proliferation ◽  
Protein Level ◽  
Cell Apoptosis ◽  
P53 Protein ◽  
Negative Regulator ◽  
Dependent Manner ◽  
Human Colorectal Cancer ◽  
Rna Interaction

Abstract Background Ribosomal L1 domain-containing protein 1 (RSL1D1) is a nucleolar protein that is essential in cell proliferation. In the current opinion, RSL1D1 translocates to the nucleoplasm under nucleolar stress and inhibits the E3 ligase activity of HDM2 via direct interaction, thereby leading to stabilization of p53. Methods Gene knockdown was achieved in HCT116p53+/+, HCT116p53−/−, and HCT-8 human colorectal cancer (CRC) cells by siRNA transfection. A lentiviral expression system was used to establish cell strains overexpressing genes of interest. The mRNA and protein levels in cells were evaluated by qRT-PCR and western blot analyses. Cell proliferation, cell cycle, and cell apoptosis were determined by MTT, PI staining, and Annexin V-FITC/PI double staining assays, respectively. The level of ubiquitinated p53 protein was assessed by IP. The protein-RNA interaction was investigated by RIP. The subcellular localization of proteins of interest was determined by IFA. Protein-protein interaction was investigated by GST-pulldown, BiFC, and co-IP assays. The therapeutic efficacy of RSL1D1 silencing on tumor growth was evaluated in HCT116 tumor-bearing nude mice. Results RSL1D1 distributed throughout the nucleus in human CRC cells. Silencing of RSL1D1 gene induced cell cycle arrest at G1/S and cell apoptosis in a p53-dependent manner. RSL1D1 directly interacted with and recruited p53 to HDM2 to form a ternary RSL1D1/HDM2/p53 protein complex and thereby enhanced p53 ubiquitination and degradation, leading to a decrease in the protein level of p53. Destruction of the ternary complex increased the level of p53 protein. RSL1D1 also indirectly decreased the protein level of p53 by stabilizing HDM2 mRNA. Consequently, the negative regulation of p53 by RSL1D1 facilitated cell proliferation and survival and downregulation of RSL1D1 remarkably inhibited the growth of HCT116p53+/+ tumors in a nude mouse model. Conclusion We report, for the first time, that RSL1D1 is a novel negative regulator of p53 in human CRC cells and more importantly, a potential molecular target for anticancer drug development.

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