Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
1.
World J Gastroenterol ; 30(14): 1990-2005, 2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38681129

RESUMO

BACKGROUND: Gastric cancer is a common malignant tumor of the digestive tract, and endoscopic submucosal dissection (ESD) is the preferred treatment for early-stage gastric cancer. The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD. AIM: To analyze the features of gastric mucosal tumors at different differentiation levels, and to explore the prognostic factors of ESD. METHODS: We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021, according to the latest Japanese guidelines (sixth edition), and divided them into low-grade intraepithelial neoplasia (LGIN), high-grade intraepithelial neoplasia (HGIN), and differentiated and undifferentiated early carcinoma. They are followed up by endoscopy, chest and abdominal computed tomography at 3, 6 and 12 months after ESD. We compared clinicopathologic characteristics, ESD efficacy, and complications with different degrees of differentiation, and analyzed the related factors associated with ESD. RESULTS: HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients (P < 0.001) and accounted for more 0-IIc (P < 0.001), atrophic gastritis was common (P < 0.001), and irregular microvascular patterns (IMVPs) and demarcation lines (DLs) were more obvious (P < 0.001). There was more infiltration in the undifferentiated carcinoma tissue (P < 0.001), more abnormal folds and poorer mucosal peristalsis (P < 0.001), and more obvious IMVPs, irregular microsurface patterns and DLs (P < 0.05) than in the LGIN and HGIN tissues. The disease-free survival rates at 2, 5, and 8 years after ESD were 95.0%, 90.1%, and 86.9%, respectively. Undifferentiated lesions (HR 5.066), white moss (HR 7.187), incomplete resection (HR 3.658), and multiple primary cancers (HR 2.462) were significantly associated with poor prognosis. CONCLUSION: Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics, which are closely related to the safety and efficacy of ESD.


Assuntos
Ressecção Endoscópica de Mucosa , Mucosa Gástrica , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/cirurgia , Neoplasias Gástricas/patologia , Ressecção Endoscópica de Mucosa/efeitos adversos , Ressecção Endoscópica de Mucosa/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Mucosa Gástrica/cirurgia , Mucosa Gástrica/patologia , Mucosa Gástrica/diagnóstico por imagem , Idoso , Resultado do Tratamento , Prognóstico , Adulto , Carcinoma in Situ/cirurgia , Carcinoma in Situ/patologia , Diferenciação Celular , Gradação de Tumores , Gastroscopia/efeitos adversos , Gastroscopia/métodos , Fatores de Tempo , Estadiamento de Neoplasias , Seguimentos
2.
Int Immunopharmacol ; 129: 111614, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38350358

RESUMO

BACKGROUND: Intestinal tissue is extremely sensitive to ionizing radiation (IR), which is easy to cause intestinal radiation sickness, and the mortality rate is very high after exposure. Recent studies have found that intestinal immune cells and intestinal stem cells (ISCs) may play a key role in IR-induced intestinal injury. METHODS: C57BL6 mice matched for age, sex and weight were randomly grouped and intraperitoneal injected with PBS, Scleroglucan (125.0 mg/kg) or Anti-mouse IL-17A -InVivo (10 mg/kg), the number of mice in each group was n ≥ 3.Survival time, body weight, pathology, organoids and immune cell markers of the mice after IR (10.0 Gy) were compared, and the mechanism of action in intestinal tissues was verified by transcriptome sequencing. RESULTS: Scleroglucan has significant radiation protective effects on the intestine, including improving the survival rate of irradiated mice, inhibiting the radiation damage of intestinal tissue, and promoting the proliferation and differentiation of intestinal stem cells (ISCs). The results of RNA sequencing suggested that Scleroglucan could significantly activate the immune system and up-regulate the IL-17 and NF-κB signaling pathways. Flow cytometry showed that Scleroglucan could significantly up-regulate the number of Th17 cells and the level of IL-17A in the gut. IL-17A provides radiation protection. After intraperitoneal injection of Scleroglucan and Anti-mouse IL-17A -InVivo, mice can significantly reverse the radiation protection effect of Scleroglucan, down-regulate the molecular markers of intestinal stem cells and the associated markers of DC, Th1 and Th17 cells, and up-regulate the associated markers of Treg and Macrophage cells. CONCLUSION: Scleroglucan may promote the proliferation and regeneration of ISCs by regulating the activation of intestinal immune function mediated by IL-17 signaling pathway and play a protective role in IR-induced injury.


Assuntos
Glucanos , Lesões por Radiação , Protetores contra Radiação , Camundongos , Animais , Interleucina-17 , Camundongos Endogâmicos C57BL , Lesões por Radiação/prevenção & controle , Transdução de Sinais , Protetores contra Radiação/farmacologia , Protetores contra Radiação/uso terapêutico , Intestinos/patologia
3.
J Cancer ; 15(6): 1770-1778, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38370378

RESUMO

Bladder cancer (BCa) is one of the most common malignancies affecting men. Oncogenic transcription factors function as an important regulator in the progression of human cancer. In our study, we aimed to construct artificial circular non-coding RNAs (acircRNAs) consisting of three functional units that mimic the CRISPR-Cas system and elucidate its therapeutic role in bladder cancer. Additionally, the compare of the efficiency in regulating gene expression between acircRNA and CRISPR-dCas systems was performed. We connected the cDNA sequences of TFs aptamer and constructed a circRNA. To demonstrate the platform's practicality, ß-catenin and NF-κB were chosen as functional targets, while T24 and 5637 cell lines served as test models. Real-time Quantitative PCR (qPCR), double luciferase assay and related phenotype assay were used to detect the expression of related genes and the therapeutic effect. To elucidate the functionality of acircRNAs, luciferase vectors capable of detecting ß-catenin and NF-κB expression were employed to assess the inhibitory impact of acircRNA on ß-catenin and NF-κB. Consequently, the optimal combination involving acircRNA-3 was determined. Next, qPCR assay was employed to assess the relative expression levels of target downstream genes following acircRNA treatment. The expression of c-myc and cyclin D1 were used to determine the function of ß-catenin, while Bcl-XL and TRAF1 were used to determine that of NF-κB. The acircRNAs inhibited the ß-catenin and NF-κB related signaling in BCa cells specifically. CD63-HuR fusion protein was used to loading acircRNA into exosomes. The results showed that acircRNA could inhibit the activity of the target transcription factors, and the inhibitory effect was better than that of CRIPSR-dCas9-KRAB. Furthermore, functional experiments demonstrated that the transfection of acircRNA in bladder cells resulted in decreased proliferation, enhanced apoptosis, and suppressed migration. In conclusion, our synthetic gene device exhibited anti-tumor regulatory capabilities and showed greater efficiency in tumor suppression compared to the CRISPR-dCas9-KRAB system. Therefore, our device provides a new strategy for cancer treatment and could be a useful strategy for cancer cells.

4.
Nature ; 626(7998): 411-418, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38297130

RESUMO

Ferroptosis, a form of regulated cell death that is driven by iron-dependent phospholipid peroxidation, has been implicated in multiple diseases, including cancer1-3, degenerative disorders4 and organ ischaemia-reperfusion injury (IRI)5,6. Here, using genome-wide CRISPR-Cas9 screening, we identified that the enzymes involved in distal cholesterol biosynthesis have pivotal yet opposing roles in regulating ferroptosis through dictating the level of 7-dehydrocholesterol (7-DHC)-an intermediate metabolite of distal cholesterol biosynthesis that is synthesized by sterol C5-desaturase (SC5D) and metabolized by 7-DHC reductase (DHCR7) for cholesterol synthesis. We found that the pathway components, including MSMO1, CYP51A1, EBP and SC5D, function as potential suppressors of ferroptosis, whereas DHCR7 functions as a pro-ferroptotic gene. Mechanistically, 7-DHC dictates ferroptosis surveillance by using the conjugated diene to exert its anti-phospholipid autoxidation function and shields plasma and mitochondria membranes from phospholipid autoxidation. Importantly, blocking the biosynthesis of endogenous 7-DHC by pharmacological targeting of EBP induces ferroptosis and inhibits tumour growth, whereas increasing the 7-DHC level by inhibiting DHCR7 effectively promotes cancer metastasis and attenuates the progression of kidney IRI, supporting a critical function of this axis in vivo. In conclusion, our data reveal a role of 7-DHC as a natural anti-ferroptotic metabolite and suggest that pharmacological manipulation of 7-DHC levels is a promising therapeutic strategy for cancer and IRI.


Assuntos
Desidrocolesteróis , Ferroptose , Humanos , Membrana Celular/metabolismo , Colesterol/biossíntese , Colesterol/metabolismo , Sistemas CRISPR-Cas/genética , Desidrocolesteróis/metabolismo , Genoma Humano , Nefropatias/metabolismo , Membranas Mitocondriais/metabolismo , Metástase Neoplásica , Neoplasias/metabolismo , Neoplasias/patologia , Fosfolipídeos/metabolismo , Traumatismo por Reperfusão/metabolismo
5.
Cancer Biol Med ; 21(1)2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172538

RESUMO

The intricate interplay between the human immune system and cancer development underscores the central role of immunotherapy in cancer treatment. Within this landscape, the innate immune system, a critical sentinel protecting against tumor incursion, is a key player. The cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) pathway has been found to be a linchpin of innate immunity: activation of this signaling pathway orchestrates the production of type I interferon (IFN-α/ß), thus fostering the maturation, differentiation, and mobilization of immune effectors in the tumor microenvironment. Furthermore, STING activation facilitates the release and presentation of tumor antigens, and therefore is an attractive target for cancer immunotherapy. Current strategies to activate the STING pathway, including use of pharmacological agonists, have made substantial advancements, particularly when combined with immune checkpoint inhibitors. These approaches have shown promise in preclinical and clinical settings, by enhancing patient survival rates. This review describes the evolving understanding of the cGAS-STING pathway's involvement in tumor biology and therapy. Moreover, this review explores classical and non-classical STING agonists, providing insights into their mechanisms of action and potential for optimizing immunotherapy strategies. Despite challenges and complexities, the cGAS-STING pathway, a promising avenue for enhancing cancer treatment efficacy, has the potential to revolutionize patient outcomes.


Assuntos
Neoplasias , Transdução de Sinais , Humanos , Nucleotidiltransferases/metabolismo , Imunidade Inata , Neoplasias/metabolismo , Imunoterapia , Microambiente Tumoral
6.
Adv Sci (Weinh) ; 11(9): e2302093, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38095513

RESUMO

Targeting ferroptosis has attracted exponential attention to eradicate cancer cells with high iron-dependent growth. Increasing the level of intracellular labile iron pool via small molecules and iron-containing nanomaterials is an effective approach to induce ferroptosis but often faces insufficient efficacy due to the fast drug metabolism and toxicity issues on normal tissues. Therefore, developing a long-acting and selective approach to regulate ferroptosis is highly demanded in cancer treatment. Herein, a lysosome-targeted magnetic nanotorquer (T7-MNT) is proposed as the mechanical tool to dynamically induce the endogenous Fe2+ pool outbreak for ferroptosis of breast cancer. T7-MNTs target lysosomes via the transferrin receptor-mediated endocytosis in breast cancer cells. Under the programmed rotating magnetic field, T7-MNTs generate torques to trigger endogenous Fe2+ release by disrupting the lysosomal membrane. This magneto-mechanical manipulation can induce oxidative damage and antioxidant defense imbalance to boost frequency- and time-dependent lipid peroxidization. Importantly, in vivo studies show that T7-MNTs can efficiently trigger ferroptosis under the magnetic field and play as a long-acting physical inducer to boost ferrotherapy efficacy in combination with RSL3. It is anticipated that this dynamic targeted strategy can be coupled with current ferroptosis inducers to achieve enhanced efficacy and inspire the design of mechanical-based ferroptosis inducers for cancer treatment.


Assuntos
Neoplasias da Mama , Ferroptose , Humanos , Feminino , Ferro , Lisossomos , Campos Magnéticos , Neoplasias da Mama/terapia
7.
Open Life Sci ; 18(1): 20220747, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37854319

RESUMO

Osteoarthritis (OA) is a painful joint disease that is common among the middle-aged and elderly populations, with an increasing prevalence. Therapeutic options for OA are limited, and the pathogenic mechanism of OA remains unclear. The roles of cytokines and signaling pathways in the development of OA is a current research hot spot. Interleukin (IL)-17 is a pleiotropic inflammatory cytokine produced mainly by T helper 17 cells that has established roles in host defense, tissue repair, lymphoid tissue metabolism, tumor progression, and pathological processes of immune diseases, and studies in recent years have identified an important role for IL-17 in the progression of OA. This narrative review focuses on the mechanisms by which IL-17 contributes to articular cartilage degeneration and synovial inflammation in OA and discusses how IL-17 and the IL-17 signaling pathway affect the pathological process of OA. Additionally, therapeutic targets that have been proposed in recent years based on IL-17 and its pathway in OA are summarized as well as recent advances in the study of IL-17 pathway inhibitors and the potential challenges of their use for OA treatment.

8.
Cancer Cell ; 41(6): 1118-1133.e12, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37267951

RESUMO

Cyclic GMP-AMP synthase (cGAS) is the major sensor for cytosolic DNA and activates type I interferon signaling and plays an essential role in antitumor immunity. However, it remains unclear whether the cGAS-mediated antitumor activity is affected by nutrient status. Here, our study reports that methionine deprivation enhances cGAS activity by blocking its methylation, which is catalyzed by methyltransferase SUV39H1. We further show that methylation enhances the chromatin sequestration of cGAS in a UHRF1-dependent manner. Blocking cGAS methylation enhances cGAS-mediated antitumor immunity and suppresses colorectal tumorigenesis. Clinically, cGAS methylation in human cancers correlates with poor prognosis. Thus, our results indicate that nutrient stress promotes cGAS activation via reversible methylation, and suggest a potential therapeutic strategy for targeting cGAS methylation in cancer treatment.


Assuntos
Cromatina , Metionina , Humanos , Cromatina/genética , Metionina/genética , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , DNA , Imunidade Inata , Desmetilação , Proteínas Estimuladoras de Ligação a CCAAT/genética , Ubiquitina-Proteína Ligases/genética
9.
Signal Transduct Target Ther ; 8(1): 104, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882399

RESUMO

Cancer immunotherapy, mainly including immune checkpoints-targeted therapy and the adoptive transfer of engineered immune cells, has revolutionized the oncology landscape as it utilizes patients' own immune systems in combating the cancer cells. Cancer cells escape immune surveillance by hijacking the corresponding inhibitory pathways via overexpressing checkpoint genes. Phagocytosis checkpoints, such as CD47, CD24, MHC-I, PD-L1, STC-1 and GD2, have emerged as essential checkpoints for cancer immunotherapy by functioning as "don't eat me" signals or interacting with "eat me" signals to suppress immune responses. Phagocytosis checkpoints link innate immunity and adaptive immunity in cancer immunotherapy. Genetic ablation of these phagocytosis checkpoints, as well as blockade of their signaling pathways, robustly augments phagocytosis and reduces tumor size. Among all phagocytosis checkpoints, CD47 is the most thoroughly studied and has emerged as a rising star among targets for cancer treatment. CD47-targeting antibodies and inhibitors have been investigated in various preclinical and clinical trials. However, anemia and thrombocytopenia appear to be formidable challenges since CD47 is ubiquitously expressed on erythrocytes. Here, we review the reported phagocytosis checkpoints by discussing their mechanisms and functions in cancer immunotherapy, highlight clinical progress in targeting these checkpoints and discuss challenges and potential solutions to smooth the way for combination immunotherapeutic strategies that involve both innate and adaptive immune responses.


Assuntos
Antígeno CD47 , Neoplasias , Humanos , Antígeno CD47/genética , Imunoterapia , Fagocitose/genética , Imunidade Inata/genética , Imunidade Adaptativa , Neoplasias/genética , Neoplasias/terapia
10.
Nat Metab ; 5(2): 265-276, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732624

RESUMO

The mechanistic target of rapamycin complex 1 (mTORC1) controls cell growth in response to amino acid and glucose levels. However, how mTORC1 senses glucose availability to regulate various downstream signalling pathways remains largely elusive. Here we report that AMP-activated protein kinase (AMPK)-mediated phosphorylation of WDR24, a core component of the GATOR2 complex, has a role in the glucose-sensing capability of mTORC1. Mechanistically, glucose deprivation activates AMPK, which directly phosphorylates WDR24 on S155, subsequently disrupting the integrity of the GATOR2 complex to suppress mTORC1 activation. Phosphomimetic Wdr24S155D knock-in mice exhibit early embryonic lethality and reduced mTORC1 activity. On the other hand, compared to wild-type littermates, phospho-deficient Wdr24S155A knock-in mice are more resistant to fasting and display elevated mTORC1 activity. Our findings reveal that AMPK-mediated phosphorylation of WDR24 modulates glucose-induced mTORC1 activation, thereby providing a rationale for targeting AMPK-WDR24 signalling to fine-tune mTORC1 activation as a potential therapeutic means to combat human diseases with aberrant activation of mTORC1 signalling including cancer.


Assuntos
Proteínas Quinases Ativadas por AMP , Alvo Mecanístico do Complexo 1 de Rapamicina , Complexos Multiproteicos , Serina-Treonina Quinases TOR , Animais , Humanos , Camundongos , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Complexos Multiproteicos/metabolismo , Fosforilação , Serina-Treonina Quinases TOR/metabolismo
11.
Nanomedicine ; 49: 102660, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36746273

RESUMO

The synergistic effect of chemotherapy and photo-dynamic therapy (PDT) is an effective way to improve the efficiency of tumor treatment. However, most synergistic therapeutic drugs have poor water solubility and stability, so it is difficult to achieve high therapeutic effects while avoiding the severe side effects. Herein, a unique dandelion-like nanomedicine (named as cRGDfk-CCPT-mCe6) was successfully synthesized using Ce6-loaded amphiphilic ß-cyclodextrins (ß-CD) doped lipid-based vesicles as the core (receptacle) and ß-CD modified camptothecin (CPT) pro-drug as the flyable dandelion seeds. The ß-CD modified CPT pro-drug was introduced into the core vesicles in succession via host-guest interaction between inter-molecular ß-CD and CPT, and cRGDfk peptides were further introduced as the outermost layer (stigma) to enhance the internalization into cancer cells. CPT interacted with ß-CD through glutathione (GSH)-cleavable disulfide bonds, which led to drug release in glutathione-rich cancer cells, just as spread of dandelion seeds in the wind. GSH consumption further disrupted the intracellular redox homeostasis of cancer cells through combined action of Ce6 with light irradiation and the synergistic anti-tumor effect was thus achieved, resulting in apoptosis of cancer cells. Therefore, the nanomedicine provides a facile and versatile anti-tumor strategy, as well as a persistent anti-cancer effects.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Humanos , Pró-Fármacos/química , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Camptotecina/química , Nanomedicina , Nanopartículas/química , Neoplasias/tratamento farmacológico , Glutationa , Linhagem Celular Tumoral
12.
Adv Sci (Weinh) ; : e2202642, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36382559

RESUMO

Lacking a clear understanding of the molecular mechanism determining cancer cell sensitivity to oxidative phosphorylation (OXPHOS) inhibition limits the development of OXPHOS-targeting cancer treatment. Here, cancer cell lines sensitive or resistant to OXPHOS inhibition are identified by screening. OXPHOS inhibition-sensitive cancer cells possess increased OXPHOS activity and silenced nicotinamide N-methyltransferase (NNMT) expression. NNMT expression negatively correlates with OXPHOS inhibition sensitivity and functionally downregulates the intracellular levels of S-adenosyl methionine (SAM). Expression of DNA methyltransferase 1 (DNMT1), a SAM consumer, positively correlates with OXPHOS inhibition sensitivity. NNMT overexpression and DNMT1 inhibition render OXPHOS inhibition-sensitive cancer cells resistant. Importantly, treatments of OXPHOS inhibitors (Gboxin and Berberine) hamper the growth of mouse tumor xenografts by OXPHOS inhibition sensitive but not resistant cancer cells. What's more, the retrospective study of 62 tumor samples from a clinical trial demonstrates that administration of Berberine reduces the tumor recurrence rate of NNMTlow /DNMT1high but not NNMThigh /DNMT1low colorectal adenomas (CRAs). These results thus reveal a critical role of the NNMT-DNMT1 axis in determining cancer cell reliance on mitochondrial OXPHOS and suggest that NNMT and DNMT1 are faithful biomarkers for OXPHOS-targeting cancer therapies.

13.
Dose Response ; 20(3): 15593258221123679, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36132708

RESUMO

Accidental radiation exposure is a threat to human health that necessitates effective clinical diagnosis. Suitable biomarkers are urgently needed for early assessment of exposure dose. Existing technologies being used to assess the extent of radiation have notable limitations. As a radiation biomarker, miRNA has the advantages of simple detection and high throughput. In this study, we screened for miRNAs with dose and time dependent responses in peripheral blood leukocytes via miRNA sequencing in establishing the animal model of acute radiation injury. Four radiation-sensitive and stably expressed miRNAs were selected out in the 24 h group of leukocyte miRNAs: mmu-miR-130b-5p, mmu-miR-148b-5p, mmu-miR-184-3p, mmu-miR-26a-2-3p, and five were screened in the 48 h group of leukocyte miRNAs: mmu-miR-130b-5p, mmu-miR-423-5p, mmu-miR-676-3p, mmu-miR-150-5p, mmu-miR-342-3p.The correlation curves between their expression and irradiation dose were plotted. Then, the results were validated by RT-qPCR in mouse peripheral blood. As a result, mmu-miR-150-5p and mmu-miR-342-3p showed the highest correlation at 48h after irradiation, and mmu-miR-130b-5p showed good correlation at both 24 h and 48 h after irradiation. In a conclusion, the miRNAs that are sensitive to ionizing radiation with dose dependent effects were selected out, which have the potential of forming a rapid assessment scheme for acute radiation injury.

14.
Stem Cell Res Ther ; 13(1): 271, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35729656

RESUMO

BACKGROUND: Severe ionizing radiation (IR)-induced intestinal injury associates with high mortality, which is a worldwide problem requiring urgent attention. In recent years, studies have found that the PHD-HIF signaling pathway may play key roles in IR-induced intestinal injury, and we found that FG-4592, the PHD inhibitor, has significant radioprotective effects on IR-induced intestinal injury. METHODS: In the presence or absence of FG-4592 treatment, the survival time, pathology, cell viability, cell apoptosis, and organoids of mice after irradiation were compared, and the mechanism was verified after transcriptome sequencing. The data were analyzed using SPSS ver. 19 software. RESULTS: Our results show that FG-4592 had significant radioprotective effects on the intestine. FG-4592 improved the survival of irradiated mice, inhibited the radiation damage of intestinal tissue, promoted the regeneration of intestinal crypts after IR and reduced the apoptosis of intestinal crypt cells. Through organoid experiments, it is found that FG-4592 promoted the proliferation and differentiation of intestinal stem cells (ISCs). Moreover, the results of RNA sequencing and Western blot showed that FG-4592 significantly upregulated the TLR4 signaling pathway, and FG-4592 had no radioprotection on TLR4 KO mice, suggesting that FG-4592 may play protective role against IR by targeting TLR4. CONCLUSION: Our work proves that FG-4592 may promote the proliferation and regeneration of ISCs through the targeted regulation of the TLR4 signaling pathway and ultimately play radioprotective roles in IR-induced injury. These results enrich the molecular mechanism of FG-4592 in protecting cells from IR-induced injury and provide new methods for the radioprotection of intestine.


Assuntos
Lesões por Radiação , Protetores contra Radiação , Animais , Apoptose , Glicina/análogos & derivados , Mucosa Intestinal/metabolismo , Intestinos , Isoquinolinas , Camundongos , Camundongos Endogâmicos C57BL , Lesões por Radiação/patologia , Protetores contra Radiação/farmacologia , Transdução de Sinais , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
15.
J Biol Chem ; 297(6): 101389, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34762910

RESUMO

SRY-box 2 (Sox2) is a transcription factor with critical roles in maintaining embryonic stem (ES) cell and adult stem cell functions and in tumorigenesis. However, how Sox2 exerts its transcriptional function remains unclear. Here, we used an in vitro protein-protein interaction assay to discover transcriptional regulators for ES cell core transcription factors (Oct4, Sox2, Klf4, and c-Myc) and identified members of the steroid receptor coactivators (SRCs) as Sox2-specific interacting proteins. The SRC family coactivators have broad roles in transcriptional regulation, but it is unknown whether they also serve as Sox2 coactivators. We demonstrated that these proteins facilitate Sox2 transcriptional activity and act synergistically with p300. Furthermore, we uncovered an acetylation-enhanced interaction between Sox2 and SRC-2/3, but not SRC-1, demonstrating it is Sox2 acetylation that promotes the interaction. We identified putative Sox2 acetylation sites required for acetylation-enhanced interaction between Sox2 and SRC-3 and demonstrated that acetylation on these sites contributes to Sox2 transcriptional activity and recruitment of SRC-3. We showed that activation domains 1 and 2 of SRC-3 both display a preferential binding to acetylated Sox2. Finally, functional analyses in mouse ES cells demonstrated that knockdown of SRC-2/3 but not SRC-1 in mouse ES cells significantly downregulates the transcriptional activities of various Sox2 target genes and impairs ES cell stemness. Taken together, we identify specific SRC family proteins as novel Sox2 coactivators and uncover the role of Sox2 acetylation in promoting coactivator recruitment and Sox2 transcriptional function.


Assuntos
Coativador 1 de Receptor Nuclear/metabolismo , Coativador 2 de Receptor Nuclear/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Fatores de Transcrição SOXB1/metabolismo , Transcrição Gênica , Acetilação , Animais , Células HEK293 , Células HeLa , Humanos , Camundongos , Coativador 1 de Receptor Nuclear/genética , Coativador 2 de Receptor Nuclear/genética , Coativador 3 de Receptor Nuclear/genética , Fatores de Transcrição SOXB1/genética
16.
Biomater Sci ; 9(16): 5542-5550, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34254095

RESUMO

Multi-functionality has been a constant pursuit in the development of next-generation drug carriers, as it will bring the potential for combination therapy by integrating diverse therapeutic modes. In this work, FeSe2 nanosheets (NSs) have been prepared as a bifunctional platform to investigate their use in synergistic cancer therapy. Bifunctional FeSe2 NSs exhibit exceptional Fenton-like activity that generates cytotoxic hydroxyl radical (˙OH) and strong broad photothermal performance including the second-infrared (NIR-II) spectral range, wherein the ˙OH production can be enhanced by NIR-II light irradiation. Furthermore, doxorubicin (DOX) was conjugated onto NSs via a pH-responsive hydrazone bond to achieve preferential drug release in an acidic microenvironment. Upon intratumoral administration, these bifunctional drug-carrying FeSe2 NSs showed an NIR-II irradiation-reinforced strong tumor suppression effect, and no obvious toxicity to normal tissues was observed. This study provides a new paradigm for the design of advanced drug carriers relying on their inherent physicochemical properties.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Linhagem Celular Tumoral , Doxorrubicina , Liberação Controlada de Fármacos , Humanos , Neoplasias/tratamento farmacológico , Fototerapia , Microambiente Tumoral
17.
Front Oncol ; 11: 696846, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34307162

RESUMO

OBJECTIVE: To investigate the clinicopathological features and follow-up of low-grade appendiceal mucinous neoplasms (LAMNs) confined to the appendix. METHODS: The clinicopathological features, pathological primary tumor (pT) staging and follow-up of 22 patients with LAMNs confined to the appendix were analyzed retrospectively. RESULTS: Of 22 patients with LAMNs, 14 were pTis (eight pTism and six pTisf), six were pT3, and two were pT4a. The appendiceal diameter was significantly larger for pTisf than for pTism. The interval between first symptoms and surgery was longer for pTisf than for pTism, but not significantly different. No significant differences were found between the pT stages and appendiceal diameter or in the interval between the first symptoms and surgery. Pathomorphologically, the epithelial structures were mainly flat (100%), undulating or scalloped (82%); a few showed filiform villous hyperplasia (46%), and seven (32%) had serrated lesions in the background. Diverticula may be associated with LAMNs, and the location of acellular mucin caused by diverticula affected the pT stage of the LAMNs. The immunohistochemistry information showed the same pattern with cytokeratin 7 (CK7) negative, cytokeratin 20 (CK20) positive and caudal type homeobox 2 (CDX-2) positive. No lymph node metastasis was found. The lack of treatment guidelines for LAMNs confined to the appendix and different acceptances of patients of preventive intervention led to varied clinical treatments. However, we found no short-term benefits of prophylactic extended resection or hyperthermic intraperitoneal chemotherapy. CONCLUSION: LAMNs confined to the appendix are rare and must be differentiated from serrated lesions and diverticula. LAMNs with different pT stages have inert biological behavior. Determining the long-term effects of preventive treatment on survival and recurrence requires more data and a longer follow-up.

18.
Chem Res Toxicol ; 34(4): 1091-1100, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33656317

RESUMO

Pyridinium aldoximes are best-known therapeutic antidotes used for clinical treatment of poisonings by organophosphorus nerve-agents and pesticides. Recently, we found that pralidoxime (2-PAM, a currently clinically used nerve-agent antidote) could also detoxify tetrachloro-1,4-benzoquinone (TCBQ), which is a carcinogenic quinoid metabolite of the widely used wood preservative pentachlorophenol under normal physiological conditions, via an unusually mild and facile Beckmann fragmentation mechanism accompanied by radical homolysis. However, it is not clear whether the less-chlorinated benzoquinones (CnBQs, n ≤ 3) act similarly; if so, what is the structure-activity relationship? In this study, we found that (1) The stability of reaction intermediates produced by different CnBQs and 2-PAM was dependent not only on the position but also the degree of Cl-substitution on CnBQs, which can be divided into TCBQ- and DCBQ (dichloro-1,4-benzoquinone)-subgroup; (2) The pKa value of hydroxlated quinones (Cn-1BQ-OHs, the hydrolysis products of CnBQs), determined the stability of corresponding intermediates, that is, the decomposition rate of the intermediates depended on the acidity of Cn-1BQ-OHs; (3) The pKa value of the corresponding Cn-1BQ-OHs could also determine the reaction ratio of Beckmann fragmentation to radical homolysis in CnBQs/2-PAM. These new findings on the structure-activity relationship of the halogenated quinoid carcinogens detoxified by pyridinium aldoxime therapeutic agents via Beckmann fragmentation and radical homolysis reaction may have broad implications on future biomedical and environmental research.


Assuntos
Benzoquinonas/química , Carcinógenos/química , Agentes Neurotóxicos/química , Oximas/química , Halogenação , Concentração de Íons de Hidrogênio , Hidrólise , Estrutura Molecular , Relação Estrutura-Atividade
20.
Cell Death Differ ; 28(1): 139-155, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32678307

RESUMO

Ovarian cancer is the most lethal malignant tumor of female reproductive system. It is well-known that induction of STING-mediated type I interferons can enhance the resultant antitumor activity. However, STING pathway is usually inactivated in cancer cells at multiple levels. Here, we identified deubiquitinase USP35 is upregulated in ovarian cancer tissues. High level of USP35 was correlated with diminished CD8+ T cell infiltration and poor prognosis in ovarian cancer patients. Mechanistically, we found that silencing USP35 reinforces the activation of STING-TBK1-IRF3 pathway and promotes the expression of type I interferons. Our data further showed that USP35 can directly deubiquitinate and inactivate STING. Interestingly, activation of STING promotes its binding to USP35 in a STING phosphorylation-dependent manner. Functionally, we found that knockdown of USP35 sensitizes ovarian cancer cells to the DNA-damage chemotherapeutic drug cisplatin. Overall, our study indicates that upregulation of USP35 may be a mechanism of the restricted STING activity in cancer cells, and highlights the significance of USP35 as a potential therapeutic target for ovarian cancer.


Assuntos
Endopeptidases/metabolismo , Interferon Tipo I/metabolismo , Neoplasias Ovarianas/genética , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Dano ao DNA/efeitos dos fármacos , Endopeptidases/genética , Feminino , Humanos , Fator Regulador 3 de Interferon/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA