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In mammals, NLRX1 is a unique member of the nucleotide-binding domain and leucine-rich repeat (NLR) family showing an ability to negatively regulate IFN antiviral immunity. Intron-containing genes, including NLRX1, have more than one transcript due to alternative splicing; however, little is known about the function of its splicing variants. Here, we identified a transcript variant of NLRX1 in zebrafish (Danio rerio), termed NLRX1-tv4, as a negative regulator of fish IFN response. Zebrafish NLRX1-tv4 was slightly induced by viral infection, with an expression pattern similar to the full-length NLRX1. Despite the lack of an N-terminal domain that exists in the full-length NLRX1, overexpression of NLRX1-tv4 still impaired fish IFN antiviral response and promoted viral replication in fish cells, similar to the full-length NLRX1. Mechanistically, NLRX1-tv4 targeted STING for proteasome-dependent protein degradation by recruiting an E3 ubiquitin ligase RNF5 to drive the K48-linked ubiquitination, eventually downregulating the IFN antiviral response. Mapping of NLRX1-tv4 domains showed that its N-terminal and C-terminal regions exhibited a similar potential to inhibit STING-mediated IFN antiviral response. Our findings reveal that like the full-length NLRX1, zebrafish NLRX-tv4 functions as an inhibitor to shape fish IFN antiviral response.IMPORTANCEIn this study, we demonstrate that a transcript variant of zebrafish NLRX1, termed NLRX1-tv4, downregulates fish IFN response and promotes virus replication by targeting STING for protein degradation and impairing the interaction of STING and TBK1 and that its N- and C-terminus exhibit a similar inhibitory potential. Our results are helpful in clarifying the current contradictory understanding of structure and function of vertebrate NLRX1s.
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Proteínas de Membrana , Proteínas Mitocondriais , Proteínas de Peixe-Zebra , Animais , Imunidade Inata , Domínios Proteicos , Isoformas de Proteínas/genética , Ubiquitina-Proteína Ligases , Ubiquitinação , Peixe-Zebra/imunologia , Peixe-Zebra/metabolismo , Proteínas Mitocondriais/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Proteínas de Membrana/metabolismo , Interferons/metabolismoRESUMO
BACKGROUND: The prognosis of hepatocellular carcinoma with portal vein tumor thrombus remains extremely poor. This pilot study aimed to evaluate the technical feasibility, effectiveness and safety of transcatheter chemoembolization for tumors in the liver parenchyma plus intra-arterial ethanol embolization for portal vein tumor thrombus. METHODS: A pilot study was carried out on 31 patients in the treatment group (transcatheter chemoembolization plus intra-arterial ethanol embolization) and 57 patients in the control group (transcatheter chemoembolization alone). Enhanced computed tomography/magnetic resonance images were repeated 4 weeks after the procedure to assess the response. Overall survival and complications were assessed until the patient died or was lost to follow-up. RESULTS: Median survival was 10.5 months in the treatment group (2.4 ± 1.7 courses) and 3.9 months in the control group (1.9 ± 1 courses) (P = 0.001). Patients in the treatment group had better overall survival (at 3, 6 and 12 months, respectively), compared to patients in the control group (90.3% vs. 59.6%, 64.5% vs. 29.8%, and 41.9% vs. 10.6%; p = 0.001). Furthermore, the rate of portal vein tumor thrombus regression was higher in the treatment group (93.1%) than in the control group (32.1%) (P < 0.001). CONCLUSIONS: Based on the results of this study, transcatheter chemoembolization combined with intra-arterial ethanol embolization may be more effective than transcatheter chemoembolization alone for treating hepatocellular carcinoma with portal vein tumor thrombus. Intra-arterial ethanol embolization for treating portal vein tumor thrombus is safe, feasible and prolongs overall survival.
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Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica , Neoplasias Hepáticas/tratamento farmacológico , Trombose Venosa/tratamento farmacológico , Adulto , Idoso , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Tomografia Computadorizada de Feixe Cônico , Etanol/administração & dosagem , Feminino , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Veia Porta/efeitos dos fármacos , Veia Porta/patologia , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/patologiaRESUMO
BACKGROUND: Recently studies have demonstrated that the long non-coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) may participate in the development and progression of lung cancer. In this study, we hypothesized that genetic variant of this lncRNA may affect the prognosis of lung cancer patients. METHODS: We conducted a follow-up study for 538 patients with non-small cell lung carcinoma (NSCLC), including 140 early-staged (stage I and II) and 398 advanced staged (stage III and IV) patients. The genetic variant rs3200401 in MALAT1 was then genotyped among this population by using TaqMan assay. The association of this variant with overall survival of these patients was further analyzed. RESULTS: It was shown that among the advanced lung adenoma patients, subjects carrying rs3200401 CT and CT + TT genotypes had significantly longer median survival time (MST = 29.9, 28.9 vs. 19.3 month, Long-rank P = 0.019 and 0.024, respectively) and decreased death risks [crude HR (95% CI) = 0.65 (0.43-0.98) and 0.64 (0.44-0.95), P = 0.040 and 0.025, respectively], when compared to subjects wtih the MALAT1 rs3200401 CC genotype. However, the beneficial effect of rs3200401 was not seen among early NSCLC and advanced lung squamous cell carcinoma patients. We further tested the TCGA data, and found that a higher expression of MALAT1 was associated with metastatic of advanced lung adenocarcinoma but not with lung squamous cell carcinoma. CONCLUSIONS: The rs3200401 T allele located on the lncRNA MALAT1 was associated with a better survival for advanced lung adenocarcinoma patients, which may offer a novel prognostic biomarker for this patient subgroup. However, these results need to be validated in larger populations of lung cancer and the biological function of this variant still warrants further investigation.
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Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Estudos de Associação Genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo de Nucleotídeo Único , Prognóstico , Modelos de Riscos ProporcionaisRESUMO
Langerhans cell histiocytosis (LCH) is a rare disease, and involvement of the atlas is extremely uncommon. Biopsy of atlas lesions is difficult and risky. In this case report, we describe the performance of percutaneous computed tomography-guided biopsy of an atlantal LCH in a patient with no complication.
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Atlas Cervical/patologia , Histiocitose de Células de Langerhans/patologia , Doenças Raras/patologia , Doenças da Coluna Vertebral/patologia , Humanos , Biópsia Guiada por Imagem , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Radiofrequency ablation (RFA) and percutaneous ethanol injection (PEI) are treatment methods for patients with early-stage hepatocellular carcinoma (HCC) who are not suitable for surgery. Although some reports indicate that RFA is better than PEI, results from previous reviews and analyses are inconsistent. Therefore, this meta-analysis was performed to more thoroughly evaluate the effects of these treatments in patients with HCC. METHODS: A literature search was conducted using the Excerpta Medica dataBASE, PubMed, the Cochrane Library, the American Society of Clinical Oncology database, the China National Knowledge Infrastructure database, the Wanfang database, the Chinese Biomedical Literature Database, and the Chongqing VIP database without language limitations. The primary outcome evaluated was overall survival, and secondary outcomes included complete response and local recurrence. Comparisons were made between Asian and European studies. RESULTS: Total pooled and subgroup analyses of Asian studies that included selection biases revealed that RFA is superior to PEI with respect to overall survival (hazard ratio (HR), 0.54; 95% confidence interval (CI), 0.37 to 0.80; P < 0.01) and complete response (relative risk (RR), 1.10; 95% CI 1.03 to 1.18; P < 0.01). However, no significant difference was observed between RFA and PEI in the European studies. In Asian studies, RFA was associated with a lower local recurrence rate than PEI at 1 year (RR, 0.44; 95% CI 0.20 to 0.95; P < 0.05) and 3 years (RR, 0.35; 95% CI 0.22 to 0.55; P < 0.01). However, local recurrence was significantly lower after only 3 years in European studies (RR, 0.50; 95% CI 0.32 to 0.78; P < 0.05). CONCLUSIONS: RFA was only superior to PEI in Asian studies that included selection bias. Thus, there is insufficient evidence to support the idea that RFA is superior to PEI for patients with cirrhotic HCC. Additional large-scale, multicenter, randomized controlled trials that control for selection bias are needed to fully elucidate the optimal treatment method for HCC.
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Anti-Infecciosos Locais/administração & dosagem , Carcinoma Hepatocelular/terapia , Ablação por Cateter , Etanol/administração & dosagem , Neoplasias Hepáticas/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Injeções , PrognósticoRESUMO
An ortho-selective C-F bond borylation between N-heterocycle-substituted polyfluoroarenes and Bpin-Bpin with simple and commercially available [Rh(cod)2 ]BF4 as a catalyst is now reported. The reaction proceeds under mild reaction conditions with high efficiency and broad substrate scope, even toward monofluoroarene, thus providing a facile access to a wide range of borylated fluoroarenes that are useful for photoelectronic materials. Preliminary mechanistic studies reveal that a Rh(III/V) catalytic cycle via a key intermediate rhodium(III) hydride complex [(H)Rh(III) Ln (Bpin)] may be involved in the reaction.
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A first example of Pd-catalyzed gem-difluoroallylation of organoborons using 3-bromo-3,3-difluoropropene (BDFP) in high efficiency with high α/γ-substitution regioselectivity has been developed. The reaction can also be extended to substituted BDFPs and has advantages of low catalyst loading (0.8 to 0.01 mol %), broad substrate scope, and excellent functional group compatibility, thus providing a facile route for practical application in drug discovery and development.
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Alcenos/química , Compostos de Boro/química , Hidrocarbonetos Halogenados/química , Hidrocarbonetos Halogenados/síntese química , Compostos Organometálicos/química , Paládio/química , Catálise , Estrutura MolecularRESUMO
Transition-metal-catalyzed difluoroalkylation of aromatics remains challenging despite the importance of difluoroalkylated arenes in medicinal chemistry. Herein, the first successful example of nickel-catalyzed difluoroalkylation of aryl boronic acids is described. The reaction allows access to a variety of functionalized difluoromethyl bromides and chlorides, and paves the way to highly cost-efficient synthesis of a wide range of difluoroalkylated arenes. The notable features of this protocol are its high generality, excellent functional-group compatibility, low-cost nickel-catalyst, and practicality for gram-scale production, thus providing a facile method for applications in drug discovery and development.
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Flúor/química , Níquel/química , Ácidos Borônicos , Catálise , Modelos Moleculares , Estrutura MolecularRESUMO
The development of CRISPR-Cas9 technology introduces an efficient tool for precise engineering of fish genomes. With a short reproduction cycle, zebrafish infection mode can be referenced as antiviral breeding researches in aquaculture fish. Previously we identified a crucian carp-specific gene ftrca1 as an inhibitor of interferon response in vitro. Here, we demonstrate that genome editing of zebrafish ftr42, a homolog of ftrca1, generates a zebrafish mutant (ftr42lof/lof) with an improved resistance to SVCV infection. Zebrafish ftr42 acts as a virus-induced E3 ligase and downregulates IFN antiviral response by facilitating TBK1 protein degradation and also IRF7 mRNA decay. Genome editing results in loss of function of zebrafish ftr42, which enables zebrafish to have enhanced interferon response, thus improving zebrafish survival against virus infection. Our results suggest that fine-tuning fish IFN innate immunity through genome editing of negative regulators can genetically improve viral resistance in fish.
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To summarize and analyze the clinical application characteristics of Qugu (CV 2) in ancient and modern literature based on data mining technology. The Chinese Medical Code (the 5th edition) was taken as the retrieval source of ancient literature, while the CNKI, Wanfang, and VIP databases were taken as the retrieval source of modern literature. The indications of Qugu (CV 2) used alone or with compatible acupoints, compatible acupoints, acupuncture-moxibustion manipulation, etc., were systematically sorted out. As a result, a total of 140 articles of ancient literature were included. The common indications of Qugu (CV 2) used alone were urinary retention, profuse vaginal discharge and hernia. The common indications of Qugu (CV 2) used with compatible acupoints were profuse vaginal discharge, stranguria and hernia. Sixty-four acupoints were concurrently used with Qugu (CV 2), Qugu (CV 2) was mainly compatible with acupoints of conception vessel, bladder meridian and liver meridian, and the high-frequency acupoints included Zhongji (CV 3), Guanyuan (CV 4) and Sanyinjiao (SP 6); five-shu points were the most used special acupoints, and moxibustion therapy was often used. A total of 73 modern articles were included. The common indications of Qugu (CV 2) used alone were urinary retention, erectile dysfunction and chronic prostatitis; the common indications of Qugu (CV 2) used with compatible scupoints were urinary retention, erectile dysfunction and prostatic hyperplasia. Thirty-six acupoints were concurrently used with Qugu (CV 2), Qugu (CV 2) was mainly compatible with acupoints of conception vessel, kidney meridian and spleen meridian, and the high-frequency acupoints included Zhongji (CV 3), Guanyuan (CV 4) and Zusanli (ST 36); front-mu points were the most used special acupoints, and acupuncture therapy was often used. Qugu (CV 2) treats a wide range of diseases in ancient times, the distant treatment effectiveness of acupoints is emphasized; and it mainly treats local diseases in modern times, the nearby treatment effectiveness of acupoints is emphasized.
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Terapia por Acupuntura , Disfunção Erétil , Literatura Moderna , Meridianos , Moxibustão , Retenção Urinária , Descarga Vaginal , Feminino , Masculino , Humanos , Pontos de AcupunturaRESUMO
Benign prostatic hyperplasia is caused by kidney deficiency and impaired qi transformation of the urinary bladder and is manifested by the stagnation of essence chamber. Based on jingjin (muscle region of meridian, sinew/fascia) theory and taking the visceral membrane as the principal, acupuncture is delivered at sinew/fascia to promote qi circulation, resolve stasis and open the orifice. Guided by CT, the needle is inserted at Zhongji (CV 3), the front-mu point of the urinary bladder, and then goes to the prostatic capsule, meaning "the disease of zang organ is treated by needling the front-mu point". In treatment of benign prostatic hyperplasia, this acupuncture therapy stimulates the different layers of fascia, by which, the defensive qi on the exterior is regulated and "essence orifice" in the interior is adjusted so that the urination can be promoted.
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Terapia por Acupuntura , Meridianos , Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/diagnóstico , Hiperplasia Prostática/terapia , Próstata , Bexiga UrináriaRESUMO
In mammals, right open reading frame kinases (RIOKs) are initially reported to participate in cancer cell proliferation, apoptosis, migration and invasion, and recently they have been related to host immune response. Little is known about the homologs of RIOKs in fish. In the current study, we cloned three homologous genes of RIOK family in yellow catfish (Pelteobagrus fulvidraco), termed Pfriok1, Pfriok2 and Pfriok3. Pfriok1, Pfriok2 and Pfriok3 were constitutively expressed at relatively high levels in yellow catfish tissues, and their mRNA levels were not changed under viral infection. Individual overexpression of PfRIOK1, PfRIOK2 and PfRIOK3 attenuated fish interferon (IFN) response, thereby promoting viral replication in fish cells. Mechanistically, yellow catfish RIOK proteins downregulated fish IFN response through attenuating TBK1 protein levels in cytoplasm. Our findings suggest that yellow catfish RIOK1, RIOK2 and RIOK3 are involved in downregulating fish IFN antiviral response.
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Peixes-Gato , Animais , Peixes-Gato/genética , Interferons , Antivirais , Proteínas de Peixes/genética , MamíferosRESUMO
BACKGROUND: Hypereosinophilic syndrome (HES) is classified as primary, secondary or idiopathic. Idiopathic HES (IHES) has a variable clinical presentation and may involve multiple organs causing severe damage. Hepatic sinusoidal obstruction syndrome (HSOS) is characterized by damage to the endothelial cells of the hepatic sinusoids of the hepatic venules, with occlusion of the hepatic venules, and hepatocyte necrosis. We report a case of IHES with HSOS of uncertain etiology. CASE SUMMARY: A 70-year-old male patient was admitted to our hospital with pruritus and a rash on the extremities for > 5 mo. He had previously undergone antiallergic treatment and herbal therapy in the local hospital, but the symptoms recurred. Relevant examinations were completed after admission. Bone marrow aspiration biopsy showed a significantly higher percentage of eosinophils (23%) with approximately normal morphology. Ultrasound-guided hepatic aspiration biopsy indicated HSOS. Contrast-enhanced computed tomography (CT) of the upper abdomen showed hepatic venule congestion with hydrothorax and ascites. The patient was initially diagnosed with IHES and hepatic venule occlusion. Prednisone, low molecular weight heparin and ursodeoxycholic acid were given for treatment, followed by discontinuation of low molecular weight heparin due to ecchymosis. Routine blood tests, biochemical tests, and imaging such as enhanced CT of the upper abdomen and pelvis were reviewed regularly. CONCLUSION: Hypereosinophilia may play a facilitating role in the occurrence and development of HSOS.
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Building on our previous work on ibrutinib-based reversible covalent Bruton's tyrosine kinase (BTK) PROTACs, we explored a different irreversible BTK inhibitor poseltinib as the BTK binder for PROTAC development. Different from ibrutinib, converting the irreversible cysteine reacting acrylamide group of poseltinib to a reversible covalent cyano-acrylamide group dramatically decreases the binding affinity to BTK by over 700 folds. Interestingly, one of the reversible covalent BTK PROTACs based on poseltinib with a rigid linker, dubbed as PS-RC-1, is highly potent (IC50 = ~10 nM) in Mino cells but not in other mantle cell lymphoma (MCL) cell lines, such as Jeko-1 and Rec-R cells. We showed that PS-RC-1 potently induces degradation of IKZF1 and IKZF3 but not BTK or GSPT1, accounting for its toxicity in Mino cells. We further decreased the molecular size of PS-RC-1 by shrinking the BTK binding moiety and developed PS-2 as a potent BTK and IKZF1/3 triple degrader with high specificity.
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Recent studies have related the membrane-associated RING-CH-type finger (MARCH) family proteins to host innate immune response. Zebrafish (Danio rerio) MARCH8 is reported to target SVCV glycoprotein for degradation; however, little is known about whether fish MARCH8 is involved in innate interferon (IFN) response. In this study, zebrafish march8 was significantly induced by SVCV infection. Overexpression of MARCH8 diminished fish IFN-mediated antiviral response, thus promoting the replication of SVCV and GCRV in fish cells. Mechanistically, MARCH8 interacts with and degrades MITA and TBK1 proteins to inhibit IFN response. Moreover, MARCH8 has an E3 ligase activity and enhances MITA and TBK1 polyubiquitination. Our findings reveal a mechanism whereby zebrafish MARCH8 downregulates fish IFN response and facilitates viral replication by targeting MITA and TBK1 for protein degradation.
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Interferons , Peixe-Zebra , Animais , Antivirais , Imunidade Inata , Interferons/metabolismo , Proteólise , Replicação ViralRESUMO
Interferon regulatory factors (IRFs) constitute a family of transcription factors that synchronize interferon (IFN) antiviral response through translocating to nucleus and binding to the promoters of IFN and IFN-stimulated genes (ISGs). Fish contain 11 IRF members; however, whether or how fish IRF family genes function in IFN response remains limited. Herein, we determine the regulatory roles of 11 zebrafish IRF family members in IFN response relevant to their subcellular localization and promoter binding. Zebrafish IRF family members display three patterns of constitutive localization, only in nucleus (IRF1/2/9/11), only in cytoplasm (IRF3/5/7), and largely in nucleus with small amounts in cytoplasm (IRF4b/6/8/10). DNA pull-down assays confirm that all zebrafish IRF proteins are capable to bind fish IFN promoters, albeit to various degrees, thus regulating IFN gene transcription as activators (IRF1/3/5/6/7/8/9/11) or repressors (IRF2/4b/10). Further characterization of distinct IFN gene activation reveals that IRF1/3/5/6/7/8/9/11 efficiently stimulate zebrafish IFNφ1 expression, and IRF1/7/11 are responsible for zebrafish IFNφ3 expression. Two conserved basic residues within the helix α3 of DNA binding domains (DBDs) contribute to constitutive or inducible nuclear import for all zebrafish IRF family members and DNA binding for most members, thereby enabling them to function as transcription factors. Our results reveal a conserved and general mechanism that specifies zebrafish IRF family proteins to nuclear import and DNA binding, thereby regulating fish IFN response.
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Interferons , Peixe-Zebra , Animais , Núcleo Celular/metabolismo , Fatores Reguladores de Interferon/metabolismo , Interferons/genética , Interferons/metabolismo , Regiões Promotoras Genéticas , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
OBJECTIVE: To investigate the enhancement effect of the combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin in the treatment of lung cancer. METHODS: Twenty five BABL/nu/nu mice bearing A549 lung cancer were divided into 5 groups (NS control, psh-Control, psh-PKM2 treated group, Endostar treated group, psh-PKM2+Endostar treated group) and treated with shRNA interfering plasmid targeting PKM2 and recombinant Endostatin respectively or in combination. The expression of PKM2 in A549 detected with immunofluorescent assay. The interference effect of psh-PKM2 was determined by Western blot. The tumor volume, microvessel density (MVD), apoptosis index (AI) and side effects were observed. RESULTS: The combination treatment of RNA interfering plasmid targeting PKM2 with recombinant Endostatin inhibited tumor growth obviously (P < 0.05); The combination group revealed a decreased MVD and an increased AI (P < 0.05). CONCLUSION: The combination of shRNA interfering plasmid targeting PKM2 with recombinant Endostatin might enhance anti-tumor effect by increasing the apoptosis of the cancer cell.
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Apoptose/fisiologia , Endostatinas/uso terapêutico , Neoplasias Pulmonares/terapia , Piruvato Quinase/genética , RNA Interferente Pequeno/genética , Animais , Linhagem Celular Tumoral , Endostatinas/biossíntese , Endostatinas/genética , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Transplante de Neoplasias , Plasmídeos/genética , Piruvato Quinase/biossíntese , Proteínas Recombinantes/uso terapêuticoRESUMO
BACKGROUND AND OBJECTIVE: Radiotherapy (RT) is a major non-surgical modality in the comprehensive treatment for colorectal adenocarcinoma. The radioresistance of cancer stem cells (CSCs) is a key factor that influences therapeutic effectiveness. This study was to investigate the effects of specific chromosome structure and histone modification in CSCs in colorectal adenocarcinoma radioresistance. METHODS: Samples were collected from resected human colorectal adenocarcinomas. Subcutaneous colorectal cancer model was established in nude mice. Immunohistochemistry showed that xenografts generated from bulk colorectal cancer cells resembled the original tumor specimen. Flow cytometry was performed to sort CSCs (CD133+) and non-CSCs (CD133-) from both resected samples of colorectal adenocarcinoma and xenograft before and after high single-dose radiation. The markers labeling heterochromatin (H3K9me3, HP1-alpha and H3K4me1) and euchromatin (H3K4me3) in CD133+ and CD133- nucleus were detected by immunofluorescence. RESULTS: There was distinct difference in chromatin structure between colorectal CSCs (CD133+) and non-CSCs (CD133-). The chromatin displayed compact patches in CD133+ nucleus, but loosely latticed structure in CD133- nucleus; immunofluorescence verified that the compact patches existing in CSCs was generated from heterochromatin construction. In addition, the vacuole-like defect in heterochromatin regions of CSCs was observed within 24 h after exposure to 10 gray (Gy) single-dose RT. Interestingly, this phenomenon was repaired from 96 h, and recovered to dense plaque structure in heterochromatin regions of CSCs after 144 h. However, no significant difference in non-CSCs was observed after RT exception for a loose chromatin structure. CONCLUSIONS: CSCs play a role in radiosensitivity in colorectal cancer. The mechanism may be related to heterochromatin formation and histone methylation.
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Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , Heterocromatina/metabolismo , Células-Tronco Neoplásicas/efeitos da radiação , Tolerância a Radiação , Antígeno AC133 , Adenocarcinoma/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos CD/metabolismo , Núcleo Celular/genética , Núcleo Celular/patologia , Neoplasias Colorretais/radioterapia , Feminino , Glicoproteínas/metabolismo , Histonas/metabolismo , Humanos , Masculino , Metilação , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Transplante de Neoplasias , Células-Tronco Neoplásicas/patologia , Aceleradores de Partículas , Peptídeos/metabolismo , Doses de RadiaçãoRESUMO
Current efforts in the proteolysis targeting chimera (PROTAC) field mostly focus on choosing an appropriate E3 ligase for the target protein, improving the binding affinities towards the target protein and the E3 ligase, and optimizing the PROTAC linker. However, due to the large molecular weights of PROTACs, their cellular uptake remains an issue. Through comparing how different warhead chemistry, reversible noncovalent (RNC), reversible covalent (RC), and irreversible covalent (IRC) binders, affects the degradation of Bruton's Tyrosine Kinase (BTK), we serendipitously discover that cyano-acrylamide-based reversible covalent chemistry can significantly enhance the intracellular accumulation and target engagement of PROTACs and develop RC-1 as a reversible covalent BTK PROTAC with a high target occupancy as its corresponding kinase inhibitor and effectiveness as a dual functional inhibitor and degrader, a different mechanism-of-action for PROTACs. Importantly, this reversible covalent strategy is generalizable to improve other PROTACs, opening a path to enhance PROTAC efficacy.
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Tirosina Quinase da Agamaglobulinemia/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Acrilamidas/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Tirosina Quinase da Agamaglobulinemia/genética , Linhagem Celular , Sobrevivência Celular , Corantes Fluorescentes , Meia-Vida , Humanos , Espaço Intracelular/metabolismo , Ligantes , Simulação de Dinâmica Molecular , Mutação , Fenômenos de Química Orgânica , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , ProteóliseRESUMO
BACKGROUND: Honokiol is a major bioactive compound extracted from Magnolia. The present study was designed to determine whether liposomal honokiol has the antitumor activity against human lung cancer as well as potentiates the antitumor activity of cisplatin in A549 lung cancer xenograft model, if so, to examine the possible mechanism in the phenomenon. METHODS: human A549 lung cancer-bearing nude mice were treated with liposomal honokiol, liposomal honokiol plus DDP or with control groups. Apoptotic cells and vessels were evaluated by fluorescent in situ TUNEL assay and by immunohistochemistry with an antibody reactive to CD31 respectively. RESULTS: The present study showed that liposomal honokiol alone resulted in effective suppression of the tumor growth, and that the combined treatment with honokiol plus DDP had the enhanced inhibition of the tumor growth and resulted in a significant increase in life span. The more apparent apoptotic cells in the tumors treated with honokiol plus DDP was found in fluorescent in situ TUNEL assay, compared with the treatment with control groups. In addition, the combination of honokiol and DDP apparently reduced the number of vessels by immunolabeling of CD31 in the tissue sections, compared with control groups. CONCLUSION: In summary, our data suggest that honokiol alone had the antitumor activity against human lung cancer in A549 lung cancer xenograft model, and that the combination of honokiol with DDP can enhance the antitumor activity, and that the enhanced antitumor efficacy in vivo may in part result from the increased induction of the apoptosis and the enhanced inhibition of angiogenesis in the combined treatment. The present findings may be of importance to the further exploration of the potential application of the honokiol alone or the combined approach in the treatment of lung carcinoma.