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1.
Anal Chim Acta ; 1305: 342588, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38677842

ABSTRACT

BACKGROUND: Sulfur dioxide (SO2) is a significant gas signaling molecule in organisms, and viscosity is a crucial parameter of the cellular microenvironment. They are both involved in regulating many physiological processes in the human body. However, abnormalities in SO2 and viscosity levels are associated with various diseases, such as cardiovascular disease, lung cancer, respiratory diseases, neurological disorders, diabetes and Alzheimer's disease. Hence, it is essential to explore novel and efficient fluorescent probes for simultaneously monitoring SO2 and viscosity in organisms. RESULTS: We selected quinolinium salt with good stability, high fluorescence intensity, good solubility and low cytotoxicity as the fluorophore and developed a highly sensitive ratiometric probe QQD to identify SO2 and viscosity changes based on Förster resonance energy transfer/twisted intramolecular charge transfer (FRET/TICT) mechanism. Excitingly, compared with other probes for SO2 detection, QQD not only identified HSO3-/SO32- with a large Stokes shift (218 nm), low detection limit (1.87 µM), good selectivity, high energy transfer efficiency (92 %) and wide recognition range (1.87-200 µM), but also identified viscosity with a 26-fold fluorescence enhancement and good linearity. Crucially, QQD was applied to detect HSO3-/SO32- and viscosity in actual water and food samples. In addition, QQD had low toxicity and good photostability for imaging HSO3-/SO32- and viscosity in cells. These results confirmed the feasibility and reliability of QQD for HSO3-/SO32- and viscosity imaging and environmental detection. SIGNIFICANCE: We reported a unique ratiometric probe QQD for detecting HSO3-/SO32- and viscosity based on the quinolinium skeleton. In addition to detecting HSO3-/SO32- and viscosity change in actual water and food samples, QQD could also monitor the variations of HSO3-/SO32- and viscosity in cells, which provided an experimental basis for further exploration of the role of SO2 derivatives and viscosity in biological systems.


Subject(s)
Fluorescence Resonance Energy Transfer , Fluorescent Dyes , Fluorescent Dyes/chemistry , Fluorescent Dyes/chemical synthesis , Viscosity , Humans , Sulfur Dioxide/analysis , Sulfites/analysis , Sulfites/chemistry , Limit of Detection , Quinolinium Compounds/chemistry
2.
Talanta ; 275: 126135, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38677165

ABSTRACT

Hydrogen peroxide (H2O2) and viscosity play vital roles in the cellular environment as signaling molecule and microenvironment parameter, respectively, and are associated with many physiological and pathological processes in biological systems. We developed a near-infrared fluorescent probe, CQ, which performed colorimetric and ratiometric detection of H2O2 and viscosity based on the FRET mechanism, and was capable of monitoring changes in viscosity and H2O2 levels simultaneously through two different channels. Based on the specific reaction of H2O2 with borate ester, CQ exhibited a significant ratiometric response to H2O2 with a large Stokes shift of 221 nm, a detection limit of 0.87 µM, a near-infrared emission wavelength of 671 nm, a response time of 1 h, a wide detection ranges of 0.87-800 µM and a high energy transfer efficiency of 99.9 %. CQ could also recognize viscosity by the TICT mechanism, and efficiently detect viscosity changes caused by food thickeners. More importantly, CQ could successfully detect endogenous/exogenous H2O2 and viscosity in live HeLa cells, which was expected to be a practical tool for detecting H2O2 and viscosity in live cells.


Subject(s)
Fluorescence Resonance Energy Transfer , Fluorescent Dyes , Hydrogen Peroxide , Hydrogen Peroxide/analysis , Hydrogen Peroxide/chemistry , Fluorescent Dyes/chemistry , Humans , HeLa Cells , Fluorescence Resonance Energy Transfer/methods , Viscosity , Infrared Rays , Limit of Detection , Cell Survival
3.
Anal Chim Acta ; 1288: 342184, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38220311

ABSTRACT

BACKGROUND: Sulfur dioxide (SO2) is a common gaseous pollutant that significantly threatens environmental pollution and human health. Meanwhile, viscosity is an essential parameter of the intracellular microenvironment, manipulating many physiological roles such as nutrient transport, metabolism, signaling regulation and apoptosis. Currently, most of the fluorescent probes used for detecting SO2 derivatives and viscosity are single-emission probes or probes based on the ICT mechanism, which suffer from short emission wavelengths, small Stokes shifts or susceptibility to environmental background. Therefore, the development of powerful high-performance probes for real-time monitoring of sulfur dioxide derivatives and viscosity is of great significance for human health. RESULTS: In this research, we designed the fluorescent probe QQC to detect SO2 derivatives and viscosity based on FRET platform with quinolinium salt as donor and quinolinium-carbazole as acceptor. QQC exhibited a ratiometric fluorescence response to SO2 with a low detection limit (0.09 µM), large Stokes shift (186 nm) and high energy transfer efficiency (95 %), indicating that probe QQC had good sensitivity and specificity. In addition, QQC was sensitive to viscosity, with an 9.10-folds enhancement of orange fluorescence and an excellent linear relationship (R2 = 0.98) between the logarithm of fluorescence intensity at 592 nm and viscosity. Importantly, QQC could not only recognize SO2 derivatives in real water samples and food, but also detect viscosity changes caused by food thickeners and thereby had broad market application prospects. SIGNIFICANCE: We have developed a ratiometric fluorescent probe based on the FRET platform for detecting sulfur dioxide derivatives and viscosity. QQC could not only successfully detect SO2 derivatives in food and water samples, but also be made into test strips for detecting HSO3-/SO32- solution. In addition, the probe was also used to detect viscosity changes caused by food thickeners. Therefore, this novel probe had significant value in food and environmental detection applications.


Subject(s)
Fluorescent Dyes , Sulfur Dioxide , Humans , Fluorescence Resonance Energy Transfer , Viscosity , Water , HeLa Cells
4.
Acta Pharmacol Sin ; 45(2): 391-404, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37803139

ABSTRACT

Hepatocellular carcinoma (HCC) is one of the most common and deadly cancers in the world. The therapeutic outlook for HCC patients has significantly improved with the advent and development of systematic and targeted therapies such as sorafenib and lenvatinib; however, the rise of drug resistance and the high mortality rate necessitate the continuous discovery of effective targeting agents. To discover novel anti-HCC compounds, we first constructed a deep learning-based chemical representation model to screen more than 6 million compounds in the ZINC15 drug-like library. We successfully identified LGOd1 as a novel anticancer agent with a characteristic levoglucosenone (LGO) scaffold. The mechanistic studies revealed that LGOd1 treatment leads to HCC cell death by interfering with cellular copper homeostasis, which is similar to a recently reported copper-dependent cell death named cuproptosis. While the prototypical cuproptosis is brought on by copper ionophore-induced copper overload, mechanistic studies indicated that LGOd1 does not act as a copper ionophore, but most likely by interacting with the copper chaperone protein CCS, thus LGOd1 represents a potentially new class of compounds with unique cuproptosis-inducing property. In summary, our findings highlight the critical role of bioavailable copper in the regulation of cell death and represent a novel route of cuproptosis induction.


Subject(s)
Carcinoma, Hepatocellular , Deep Learning , Liver Neoplasms , Humans , Carcinoma, Hepatocellular/drug therapy , Copper , Liver Neoplasms/drug therapy , Ionophores , Apoptosis
5.
Nat Commun ; 14(1): 6333, 2023 10 10.
Article in English | MEDLINE | ID: mdl-37816705

ABSTRACT

The severe fever with thrombocytopenia syndrome virus (SFTSV) is a tick-borne human-infecting bunyavirus, which utilizes two envelope glycoproteins, Gn and Gc, to enter host cells. However, the structure and organization of these glycoproteins on virion surface are not yet known. Here we describe the structure of SFTSV determined by single particle reconstruction, which allows mechanistic insights into bunyavirus assembly at near-atomic resolution. The SFTSV Gn and Gc proteins exist as heterodimers and further assemble into pentameric and hexameric peplomers, shielding the Gc fusion loops by both intra- and inter-heterodimer interactions. Individual peplomers are associated mainly through the ectodomains, in which the highly conserved glycans on N914 of Gc play a crucial role. This elaborate assembly stabilizes Gc in the metastable prefusion conformation and creates some cryptic epitopes that are only accessible in the intermediate states during virus entry. These findings provide an important basis for developing vaccines and therapeutic drugs.


Subject(s)
Orthobunyavirus , Phlebovirus , Severe Fever with Thrombocytopenia Syndrome , Humans , Viral Envelope Proteins/metabolism , Cryoelectron Microscopy , Glycoproteins/metabolism
7.
Int J Radiat Oncol Biol Phys ; 117(4): 942-954, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37244630

ABSTRACT

PURPOSE: The aim of this work was to explore the role and mechanism of active DNA demethylase in colorectal cancer (CRC) radiation sensitization and better understand the function of DNA demethylation in tumor radiosensitization. METHODS AND MATERIALS: Tested the effect of ten-eleven translocation 3 (TET3) overexpression on the sensitivity of CRC to radiation therapy through G2/M arrest, apoptosis, and clonogenic suppression. TET3 knockdown HCT 116 and TET3 knockdown LS 180 cell lines were constructed by siRNA technology, and the effect of exogenous knockdown of TET3 on radiation-induced apoptosis, cell cycle arrest, DNA damage, and clone formation in CRC cells were detected. The co-localization of TET3 and small ubiquitin-like modifier 1 (SUMO1), SUMO2/3 was detected by immunofluorescence and cytoplasmic-nuclear extraction, and the interaction between TET3 and SUMO1, SUMO2/3 was detected by a coimmunoprecipitation assay. RESULTS: The malignant phenotype and radiosensitivity of CRC cell lines were favorably linked with TET3 protein and mRNA expression. TET3 is upregulated in 23 of the 27 tumor types investigated, including colon cancer. TET3 was shown to correlate with the CRC pathologic malignancy grade positively. Overexpression of TET3 in CRC cell lines increased radiation-induced apoptosis, G2/M phase arrest, DNA damage, and clonal suppression in vitro. The binding region of TET3 and SUMO2/3 was located at 833-1795 AA except for K1012, K1188, K1397, and K1623. SUMOylation of TET3 increased the stability of the TET3 protein without changing its nuclear localization. CONCLUSIONS: We report the sensitizing role of TET3 protein in the radiation of CRC cells, depending on SUMO1 modification of TET3 at the lysine sites (K479, K758, K1012, K1188, K1397, K1623), in turn stabilizing TET3 expression in the nucleus and subsequently increasing the sensitivity of CRC to radiation therapy. Together, this study highlights the potentially critical role of TET3 SUMOylation in radiation regulation, which may contribute to an enhanced understanding of the relationship between DNA demethylation and radiation therapy.

8.
Mol Oncol ; 17(5): 901-916, 2023 05.
Article in English | MEDLINE | ID: mdl-36495128

ABSTRACT

The biological functions of short open reading frame (sORF)-encoded micropeptides remain largely unknown. Here, we report that LINC00998, a previously annotated lncRNA, was upregulated in multiple cancer types and the sORF on LINC00998 encoded a micropeptide named SMIM30. SMIM30 was localized in the membranes of the endoplasmic reticulum (ER) and mitochondria. Silencing SMIM30 inhibited the proliferation of hepatoma cells in vitro and suppressed the growth of tumor xenografts and N-nitrosodiethylamine-induced hepatoma. Overexpression of the 5'UTR-sORF sequence of LINC00998, encoding wild-type SMIM30, enhanced tumor cell growth, but this was abolished when a premature stop codon was introduced into the sORF via single-base deletion. Gain- and loss-of-function studies revealed that SMIM30 peptide but not LINC00998 reduced cytosolic calcium level, increased CDK4, cyclin E2, phosphorylated-Rb and E2F1, and promoted the G1/S phase transition and cell proliferation. The effect of SMIM30 silencing was attenuated by a calcium chelator or the agonist of sarco/endoplasmic reticulum calcium ATPase (SERCA) pump. These findings suggest a novel function of micropeptide SMIM30 in promoting G1/S transition and cell proliferation by enhancing SERCA activity and reducing cytosolic calcium level.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , RNA, Long Noncoding , Humans , Calcium/metabolism , Calcium-Transporting ATPases/metabolism , Cell Cycle , Micropeptides
9.
Biomed Opt Express ; 14(12): 6563-6578, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38420298

ABSTRACT

In clinical screening, accurate diagnosis of various diseases relies on the extraction of blood vessels from fundus images. However, clinical fundus images often suffer from uneven illumination, blur, and artifacts caused by equipment or environmental factors. In this paper, we propose a unified framework called ESDiff to address these challenges by integrating retinal image enhancement and vessel segmentation. Specifically, we introduce a novel diffusion model-based framework for image enhancement, incorporating mask refinement as an auxiliary task via a vessel mask-aware diffusion model. Furthermore, we utilize low-quality retinal fundus images and their corresponding illumination maps as inputs to the modified UNet to obtain degradation factors that effectively preserve pathological features and pertinent information. This approach enhances the intermediate results within the iterative process of the diffusion model. Extensive experiments on publicly available fundus retinal datasets (i.e. DRIVE, STARE, CHASE_DB1 and EyeQ) demonstrate the effectiveness of ESDiff compared to state-of-the-art methods.

10.
Cells ; 11(19)2022 09 30.
Article in English | MEDLINE | ID: mdl-36231051

ABSTRACT

Radiation-induced skin wound/dermatitis is one of the common side effects of radiotherapy or interventional radiobiology. Gingiva-derived mesenchymal stem cells (GMSCs) were indicated to have therapeutic potentials in skin diseases. However, stem cells are prone to spread and difficult to stay in the skin for a long time, limiting their curative effects and application. This study investigated the therapeutic efficacy of Nap-GDFDFpDY (pY-Gel) self-assembled peptide hydrogel-encapsulated GMSCs to treat 137Cs γ-radiation-induced skin wounds in mice. The effects were evaluated by skin damage score, hind limb extension measurement and histological and immunohistochemical analysis. In vivo studies showed that pY-Gel self-assembled peptide hydrogel-encapsulated GMSCs could effectively improve wound healing in irradiated skin tissues. In addition, it was found that GMSCs conditioned medium (CM) could promote the proliferation, migration and DNA damage repair ability of skin cells after irradiation in human keratinocyte cell line HaCaT and normal human dermal fibroblasts (HFF). Mechanistically, GMSCs-CM can promote the expression of epidermal growth factor receptor (EGFR), signal transducers and activators of transcription 3 (STAT3) and matrix metalloproteinases (MMPs), suggesting that activation of the EGFR/STAT3 signaling pathway may be involved in the repair of skin cells after exposure to radiations. In conclusion, pY-Gel self-assembled peptide hydrogel-encapsulated GMSCs have a beneficial therapeutic effect on radiation-induced cutaneous injury and may serve as a basis of novel cells therapeutic approach.


Subject(s)
Mesenchymal Stem Cells , Radiation Injuries , Animals , Culture Media, Conditioned/pharmacology , ErbB Receptors/metabolism , Gingiva , Humans , Hydrogels/pharmacology , Mesenchymal Stem Cells/metabolism , Mice , Radiation Injuries/metabolism , Radiation Injuries/therapy
11.
Front Genet ; 13: 931640, 2022.
Article in English | MEDLINE | ID: mdl-35832189

ABSTRACT

At present, with the rapid increase of emergency knowledge and the improvement of people's requirements for medical quality, the traditional teaching mode cannot fully meet the needs of emergency teaching in the new era. PBL is a project-based teaching that allows students to have a deeper understanding of content knowledge and to better apply what they have learned to their lives. This paper aims to improve the clinical emergency teaching mode by PBL teaching method, and improve the comprehensive ability of clinical emergency of medical students. This article proposes a problem-based PBL imaging teaching method, combining the characteristics and content of clinical emergency courses, focusing on students, highlighting the problem-solving process, and improving students' creative thinking ability. To cultivate students' interest in clinical learning, develop their self-learning ability, train their teamwork and communication skills, and cultivate their ability to set, question and solve questions, so as to promote medical students' overall comprehensive ability to integrate specialized knowledge and clinical practice. In this paper, the PBL teaching method and the traditional teaching method of comparative experiments show that the PBL teaching method can more effectively highlight the characteristics of clinical emergency medicine teaching mode, and make full use of the limited emergency teaching resources, so as to improve the quality of clinical emergency teaching. Compared with the traditional teaching mode, the theoretical knowledge and clinical operation skills of medical students under the PBL teaching mode are improved by 13%, Autonomous learning ability, communication ability and creative thinking ability have also been relatively improved.

12.
Anal Chim Acta ; 1211: 339908, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35589226

ABSTRACT

Sulfur dioxide derivatives (HSO3- and SO32-) play an important role in food preservative, antibacterial, antioxidant and other aspects, so it is urgent for us to develop more efficient detection methods to broaden their application in biochemical research and related disease diagnosis. Fluorescent probes are of particular interest because of their simplicity and high temporal and spatial resolution. Herein, we constructed a new near-infrared (NIR) fluorescence probe, CQC, composed of coumarin fluorophore and quinoline fluorophore, for detecting SO2 derivatives. The near-infrared emission probe CQC with a large Stokes shift (260 nm) not only kept the distance between the two emission peaks large enough (165 nm), but also had a particularly high energy transfer efficiency (99.5%), and was particularly sensitive to the detection of HSO3-/SO32- (LOD: 0.1 µM). The powerful probe CQC succeeded in real-time visualizing endogenous HSO3-/SO32- in living cells.


Subject(s)
Quinolines , Sulfur Dioxide , Coumarins , Fluorescent Dyes , HeLa Cells , Humans
13.
Front Pharmacol ; 13: 887822, 2022.
Article in English | MEDLINE | ID: mdl-35586041

ABSTRACT

Colorectal cancer (CRC) is a major public health problem on a global scale by virtue of its relatively high incidence. The transition of tumor cells from an epithelial to a mesenchymal-like phenotype, so-called epithelial-to-mesenchymal transition (EMT), is a key hallmark of human cancer metastasis, including CRC. Understanding the signaling events that initiate this phenotypic switch may provide opportunities to limit the metastasis of CRC. In this study, we aim to identify long non-coding RNA (lncRNA) mediated epigenetic regulation under the context of CRC. 54 paired samples of tumor tissues and surrounding non-tumor tissues were collected from CRC patients. Cultured human CRC cells HCT116 and LoVo were assayed for their viability and migration using CCK-8 tests and transwell migration assays. The expression of EMT-specific markers (E-cadherin, N-cadherin and vimentin) was analyzed biochemically by RT-qPCR and immunoblot analyses. Interaction among LINC00586, LSD1, and ASXL1 was determined by RNA immunoprecipitation and chromatin immunoprecipitation. In vivo analysis of LINC00586 was performed in nude mice xenografted with HCT116 cells. LINC00586 was overexpressed in CRC tissues and associated with patient survival. LINC00586 knockdown repressed HCT116 and LoVo cell viability, migration, their phenotypic switch from epithelial to a mesenchymal, and tumorigenesis in vivo. We demonstrated LINC00586 recruited the LSD1 into the ASXL1 promoter region and epigenetically silenced the ASXL1 expression. An ASXL1 gene resisting to LINC00586 attack was demonstrated in cultured HCT116 and LoVo cells and mouse xenograft models of human CRC. Overall, discovery of the LINC00586/LSD1/ASXL1 axis partially explains epigenetic mechanism regulating EMT in CRC, providing a therapeutic target to limit CRC metastasis.

14.
Medicine (Baltimore) ; 101(5): e28757, 2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35119034

ABSTRACT

RATIONALE: Multifocal intraocular lenses (IOLs) are used widely. However, the discovery of LS-313 MF15/30 (Oculentis B.V.) opacity during surgery has not yet been reported. This article reports 3 cases of LS-313 MF15/30 (Oculentis B.V.) IOL opacity found during cataract surgery implantation within 1 month. PATIENT CONCERNS: Three patients underwent cataract surgery, and opacification of their IOL (LS-313 MF15/30, Oculentis B.V.) was found intraoperatively. DIAGNOSIS: The patient was diagnosed with a postoperative intraocular opacity. INTERVENTIONS: In case 1, the surgeon scrubbed the IOL with intraocular perfusion fluid and a gelatin sponge swab to reduce opacity in the central optical area of the IOL and then implanted it into the capsule bag. In case 2, the surgeon used the infusion-aspiration polishing mode for cleaning. To avoid IOL wear and bag damage, washing was stopped when turbidity in the center of the optical area was reduced. In case 3, we learned from our previous experience that the surgeon cut the IOL into 2 pieces and moved it out at the main incision, which was replaced and implanted with a brand new IOL, after the implanted IOL was again found cloudy. OUTCOMES: In case 1, more than 10 months after the surgery, the IOL was restored to transparency, no obvious eye discomfort was noted, and uncorrected visual acuity was 20/25. In case 2, the patient's IOL surrounding area was still partially turbid after more than 10 months of follow-up. In case 3, the patient's uncorrected visual acuity on postoperative day 1 was 20/20, and the best-corrected visual acuity was 20/20. LESSON: There are many reasons for the opacification of the IOL. In addition to the patient's own factors, the material, production, and packaging of the IOL, as well as the influence of external environmental temperature, the influence of the IOL implant instrument should not be ignored and needs to be considered.


Subject(s)
Cataract , Lens Implantation, Intraocular/adverse effects , Lenses, Intraocular , Phacoemulsification , Humans , Prosthesis Design , Refraction, Ocular
16.
Org Biomol Chem ; 19(33): 7246-7251, 2021 09 07.
Article in English | MEDLINE | ID: mdl-34387642

ABSTRACT

We developed herein a regioselective construction of non-C2 symmetrical NOBIN-type biaryls through a cascade N-arylation and [3,3]-sigmatropic rearrangement from O-arylhydroxylamines and diaryliodonium salts under mild conditions. The employment of copper salt could inhibit the further O-arylation of the newly formed biaryl products, otherwise, O-arylated NOBIN-type products were furnished in moderate to good isolated yields. The products of this protocol can be further converted into highly valuable functional molecules and heterocycles.

17.
Ann Transl Med ; 9(24): 1769, 2021 Dec.
Article in English | MEDLINE | ID: mdl-35071463

ABSTRACT

BACKGROUND: Patients over 65 years old with diffuse large B-cell lymphoma (DLBCL) or follicular lymphoma (FL) relapse or being refractory to rituximab-associated chemotherapy have limited treatment options. Chidamide has the ability to enhance the sensitivity of rituximab-resistant tumors in vivo has been confirmed. We aimed to assess the activity and safety profile of chidamide plus rituximab in elderly Chinese patients with recurrent or refractory B-cell lymphoma. METHODS: In this prospective, single-arm phase II trial, we enrolled patients from three hospitals in China with histopathological diagnoses of DLBCL and FL who had relapsed or were refractory to previous lines of rituximab-associated chemotherapy. Patients were given chidamide (10 mg on days 1-6 and 8-14) and rituximab (375 mg/m2 on day 7). The treatments were repeated every 21 days. The primary endpoint was the objective response rate (ORR). The secondary endpoints included the disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety. RESULTS: Thirteen patients were enrolled and commenced treatment between November 12, 2018, and December 24, 2020. As of March 20, 2021, two patients (15.4%) were still receiving treatment. The median follow-up was 13.4 months. The ORR was 40% for the DLBCL cohort (n=10), and 100% for the FL cohort (n=3). DLBCL patients had a median PFS (mPFS) of 2.6 months (0.9-31.2 months) and a median OS (mOS) of 16.7 months (2.3-13.6 months). Neither mPFS nor mOS was reached in the FL cohort. The most frequent treatment-related adverse events (TRAEs) were leukopenia (38.5%), neutropenia (30.8%), lymphopenia (30.8%), thrombocytopenia (30.8%), fatigue (38.5%), and hyperuricemia (30.8%). CONCLUSIONS: Chidamide plus rituximab is clinically effective with an acceptable toxicity profile in elderly patients over 65 years old with relapsed or refractory DLBCL and FL. Further investigation is ongoing.

18.
Adv Sci (Weinh) ; 7(21): 2001364, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33173727

ABSTRACT

Acetylation is a critical mechanism to modulate tumor-suppressive activity of p53, but the causative roles of long non-coding RNAs (lncRNAs) in p53 acetylation and their biological significance remain unexplored. Here, lncRNA LOC100294145 is discovered to be transactivated by p53 and is thus designated as lnc-Ip53 for lncRNA induced by p53. Furthermore, lnc-Ip53 impedes p53 acetylation by interacting with histone deacetylase 1 (HDAC1) and E1A binding protein p300 (p300) to prevent HDAC1 degradation and attenuate p300 activity, resulting in abrogation of p53 activity and subsequent cell proliferation and apoptosis resistance. Mouse xenograft models reveal that lnc-Ip53 promotes tumor growth and chemoresistance in vivo, which is attenuated by an HDAC inhibitor. Silencing lnc-Ip53 inhibits the growth of xenografts with wild-type p53, but not those expressing acetylation-resistant p53. Consistently, lnc-Ip53 is upregulated in multiple cancer types, including hepatocellular carcinoma (HCC). High levels of lnc-Ip53 is associated with low levels of acetylated p53 in human HCC and mouse xenografts, and is also correlated with poor survival of HCC patients. These findings identify a novel p53/lnc-Ip53 negative feedback loop in cells and indicate that abnormal upregulation of lnc-Ip53 represents an important mechanism to inhibit p53 acetylation/activity and thereby promote tumor growth and chemoresistance, which may be exploited for anticancer therapy.

19.
PLoS One ; 15(9): e0238810, 2020.
Article in English | MEDLINE | ID: mdl-32915856

ABSTRACT

Previous studies reported that sea buckthorn (Hippophae rhamnoides L., Elaeagnaceae, HRP) exhibits hepatoprotective effects via its anti-inflammatory and antioxidant properties as well as its inhibitory effects on collagen synthesis. However, it is unclear whether this hepatoprotective effect is also achieved by regulating liver drug metabolism enzyme pathways. Herein, we examined the regulatory effect of HRP on cytochrome P450 3A (CYP3A) in rats with immune liver injury, and explored the molecular mechanism of its hepatoprotective effect. Rat models of immunological liver injury were induced by intravenous injections of Bacillus Calmette-Guerin (BCG; 125 mg kg-1; 2 wks). Specific protein levels were detected by ELISA or western blot, and CYP3A mRNA expression was detected by RT-PCR. High-performance liquid chromatography (HPLC) detected relative changes in CYP3A metabolic activity based on the rates of 1-hydroxylation of the probe drug midazolam (MDZ). BCG pretreatment (125 mg kg-1) significantly down-regulated liver CYP3A protein expression compared with the control, metabolic activity, and transcription levels while up-regulating liver NF-κB, IL-1ß, TNF-α and iNOS. HRP intervention (ED50: 78 mg kg-1) moderately reversed NF-κB, inflammatory cytokines, and iNOS activation in a dose-dependent manner (P < 0.05), and suppressed CYP3A down-regulation (P < 0.05); thereby partially alleviating liver injury. During immune liver injury, HRP may reverse CYP3A down-regulation by inhibiting NF-κB signal transduction, and protect liver function, which involves regulation of enzymes transcriptionally, translationally and post-translationally. The discovery that NF-κB is a molecular target of HRP may initiate the development and optimization of a clinical therapeutic approach to mitigate hepatitis B and other immunity-related liver diseases.


Subject(s)
Cytochrome P-450 CYP3A/genetics , Down-Regulation/drug effects , Elaeagnaceae/metabolism , Mycobacterium bovis/physiology , NF-kappa B/metabolism , Animals , Cytochrome P-450 CYP3A/metabolism , Interleukin-1beta/metabolism , Liver/drug effects , Liver/metabolism , Liver/microbiology , Liver/pathology , Male , Nitric Oxide Synthase Type II/metabolism , Protein Processing, Post-Translational/drug effects , Rats , Rats, Sprague-Dawley , Transcription, Genetic/drug effects , Tumor Necrosis Factor-alpha/metabolism
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