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1.
Sci Rep ; 14(1): 10706, 2024 05 10.
Article in English | MEDLINE | ID: mdl-38729979

ABSTRACT

Wildfires, as an environmental filter, are pivotal ecological disturbances that reshape plant communities and soil dynamics, playing a crucial role in regulating biogeographic patterns and ecosystem services. In this study, we aim to explore the effects of wildfires on forest ecosystems, specifically focusing on the plant-soil feedback mechanisms within the northeastern margin of the Qinghai-Tibet Plateau (QTP). Utilizing Partial Least Squares Path Modeling (PLS-PM), we investigated the interrelationships among soil physicochemical properties, enzyme activities, species diversity, and community stability at varying post-fire recovery stages (5, 15, and 23 years). Results indicated that in the early recovery stages, rapid changes in soil properties such as decreased pH (p < 0.001) and increased nutrient availability facilitate the emergence of early successional species with high resource utilization traits. As the ecosystem evolved toward a climax community, the soil and vegetation exhibit increased stability. Furthermore, soil enzyme activities displayed dynamic patterns that corresponded with changes in soil nutrient content, directly influencing the regeneration and diversity of plant communities. Importantly, our study documented a transition in the influence of soil properties on community stability from direct positive effects in initial recovery phases to negative impacts in later stages, while indirect benefits accrue through increased species diversity and enzyme activity. Vegetation composition and structure changed dynamically with recovery time during community succession. Plant nutrient absorption and accumulation affected nutrient dynamics in the soil, influencing plant regeneration, distribution, and diversity. Our results underscore the complex interactions between soil and vegetation that drive the recovery dynamics post-wildfire, highlighting the resilience of forest ecosystems to fire disturbances. This study contributes to the understanding of post-fire recovery processes and offers valuable insights for the management and restoration of fire-affected forest ecosystems.


Subject(s)
Ecosystem , Soil , Wildfires , Soil/chemistry , Tibet , Forests , Biodiversity , Plants/metabolism
2.
J Immunother Cancer ; 12(5)2024 May 07.
Article in English | MEDLINE | ID: mdl-38719544

ABSTRACT

OBJECTIVE: To evaluate the safety and preliminary efficacy of YSCH-01 (Recombinant L-IFN adenovirus) in subjects with advanced solid tumors. METHODS: In this single-center, open-label, investigator-initiated trial of YSCH-01, 14 patients with advanced solid tumors were enrolled. The study consisted of two distinct phases: (1) the dose escalation phase and (2) the dose expansion phase; with three dose groups in the dose escalation phase based on dose levels (5.0×109 viral particles (VP)/subject, 5.0×1010 VP/subject, and 5.0×1011 VP/subject). Subjects were administered YSCH-01 injection via intratumoral injections. The safety was assessed using National Cancer Institute Common Terminology Criteria for Adverse Events V.5.0, and the efficacy evaluation was performed using Response Evaluation Criteria in Solid Tumor V.1.1. RESULTS: 14 subjects were enrolled in the study, including 9 subjects in the dose escalation phase and 5 subjects in the dose expansion phase. Of the 13 subjects included in the full analysis set, 4 (30.8%) were men and 9 (69.2%) were women. The most common tumor type was lung cancer (38.5%, 5 subjects), followed by breast cancer (23.1%, 3 subjects) and melanoma (23.1%, 3 subjects). During the dose escalation phase, no subject experienced dose-limiting toxicities. The content of recombinant L-IFN adenovirus genome and recombinant L-IFN protein in blood showed no trend of significant intergroup changes. No significant change was observed in interleukin-6 and interferon-gamma. For 11 subjects evaluated for efficacy, the overall response rate with its 95% CI was 27.3% (6.02% to 60.97%) and the disease control rate with its 95% CI was 81.8% (48.22% to 97.72%). The median progression-free survival was 4.97 months, and the median overall survival was 8.62 months. In addition, a tendency of decrease in the sum of the diameters of target lesions was observed. For 13 subjects evaluated for safety, the overall incidence of adverse events (AEs) was 92.3%, the overall incidence of adverse drug reactions (ADRs) was 84.6%, and the overall incidence of >Grade 3 AEs was 7.7%, while no AEs/ADRs leading to death occurred. The most common AEs were fever (69.2%), nausea (30.8%), vomiting (30.8%), and hypophagia (23.1%). CONCLUSIONS: The study shows that YSCH-01 injections were safe and well tolerated and exhibited preliminary efficacy in patients with advanced solid tumors, supporting further investigation to evaluate its efficacy and safety. TRIAL REGISTRATION NUMBER: NCT05180851.


Subject(s)
Neoplasms , Adult , Aged , Female , Humans , Male , Middle Aged , Adenoviridae/genetics , Neoplasms/drug therapy , Oncolytic Virotherapy/methods , Oncolytic Virotherapy/adverse effects , Treatment Outcome
3.
J Drug Target ; 32(3): 223-240, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38252514

ABSTRACT

Survivin holds significant importance as a member of the inhibitor of apoptosis protein (IAP) family due to its predominant expression in tumours rather than normal terminally differentiated adult tissues. The high expression level of survivin in tumours is closely linked to chemotherapy resistance, heightened tumour recurrence, and increased tumour aggressiveness and serves as a negative prognostic factor for cancer patients. Consequently, survivin has emerged as a promising therapeutic target for cancer treatment. In this review, we delve into the various biological characteristics of survivin in cancers and its pivotal role in maintaining immune system homeostasis. Additionally, we explore different therapeutic strategies aimed at targeting survivin.


Subject(s)
Neoplasms , Adult , Humans , Survivin/therapeutic use , Neoplasms/drug therapy , Inhibitor of Apoptosis Proteins/genetics , Inhibitor of Apoptosis Proteins/metabolism , Inhibitor of Apoptosis Proteins/therapeutic use , Apoptosis , Microtubule-Associated Proteins/physiology , Microtubule-Associated Proteins/therapeutic use
4.
Neurooncol Adv ; 5(1): vdad117, 2023.
Article in English | MEDLINE | ID: mdl-37841695

ABSTRACT

Background: The development of new therapies for malignant gliomas has been stagnant for decades. Through the promising outcomes in clinical trials of oncolytic virotherapy, there is now a glimmer of hope in addressing this situation. To further enhance the antitumor immune response of oncolytic viruses, we have equipped a modified oncolytic adenovirus (oAds) with a recombinant interferon-like gene (YSCH-01) and conducted a comprehensive evaluation of the safety and efficacy of this modification compared to existing treatments. Methods: To assess the safety of YSCH-01, we administered the oAds intracranially to Syrian hamsters, which are susceptible to adenovirus. The efficacy of YSCH-01 in targeting glioma was evaluated through in vitro and in vivo experiments utilizing various human glioma cell lines. Furthermore, we employed a patient-derived xenograft model of recurrent glioblastoma to test the effectiveness of YSCH-01 against temozolomide. Results: By modifying the E1A and adding survivin promoter, the oAds have demonstrated remarkable safety and an impressive ability to selectively target tumor cells. In animal models, YSCH-01 exhibited potent therapeutic efficacy, particularly in terms of its distant effects. Additionally, YSCH-01 remains effective in inhibiting the recurrent GBM patient-derived xenograft model. Conclusions: Our initial findings confirm that a double-modified oncolytic adenovirus armed with a recombinant interferon-like gene is both safe and effective in the treatment of malignant glioma. Furthermore, when utilized in combination with a targeted therapy gene strategy, these oAds exhibit a more profound effect in tumor therapy and an enhanced ability to inhibit tumor growth at remote sites.

5.
BMC Cancer ; 22(1): 1039, 2022 Oct 04.
Article in English | MEDLINE | ID: mdl-36195847

ABSTRACT

BACKGROUND: Although evidence has revealed that miR-200a-3p is involved in the malignant progression of various tumors, the regulatory mechanism of miR-200a-3p in the development of cervical cancer (CC) cells with different HPV statuses remains unknown. The present study was to investigate the differential effects of either miR-200a-3p or YAP on tumorous cells' fate in vitro in HPV-negative and HPV-positive cervical cancer cell models, and to explore if the changes in proliferation, migration, and invasion of the CC cells with different HPV statuses could be attributed to the differential interactions between miR-200a-3p and YAP. METHODS: The colony formation assays, EDU assays and Transwell assays were performed for CC cell proliferation, migration and invasion capacities analysis. The prediction of downstream targets of miR-200a-3p was performed by bioinformatical databases. The dual-luciferase reporter assays were used to validate the binding sites of miR-200a-3p and YAP. The qRT-PCR assays were performed to quantify the mRNA expression of miR-200a-3p and YAP, and the protein levels of YAP were examined by Western blot analysis. RESULTS: The results demonstrated that miR-200a-3p overexpression suppressed proliferation, migration, and invasion of the HPV-negative C33A cells but promoted the growth and metastasis of HPV-positive CC cells, while YAP promoted the cell growth and metastasis not only in HPV-negative but also in the HPV-positive CC cells. The suppressive role of miR-200a-3p in C33A cells appeared to be mediated partially by direct interaction with YAP, and YAP might participate in miR-200a-3p-mediated cellular changes in CC cells differing from not only the presence or absence of HPV but even also the subtypes of HPV of CC cells. Meanwhile, we preliminarily revealed that the expression level of miR-200a-3p was significantly decreased in HPV-negative, but not in HPV16-positive cervical neoplasm mucus samples. CONCLUSION: miR-200a-3p-mediated functional changes of YAP exhibited regulatory effects on cells' fate differentially in HPV-negative and HPV-positive cervical cancer cells.


Subject(s)
MicroRNAs , Papillomavirus Infections , Uterine Cervical Neoplasms , Cell Cycle Proteins , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , MicroRNAs/genetics , MicroRNAs/metabolism , Neoplastic Processes , Papillomavirus Infections/complications , Papillomavirus Infections/genetics , RNA, Messenger , Transcription Factors , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology
6.
Nat Commun ; 12(1): 1940, 2021 03 29.
Article in English | MEDLINE | ID: mdl-33782411

ABSTRACT

Metabolic enzymes and metabolites display non-metabolic functions in immune cell signalling that modulate immune attack ability. However, whether and how a tumour's metabolic remodelling contributes to its immune resistance remain to be clarified. Here we perform a functional screen of metabolic genes that rescue tumour cells from effector T cell cytotoxicity, and identify the embryo- and tumour-specific folate cycle enzyme methylenetetrahydrofolate dehydrogenase 2 (MTHFD2). Mechanistically, MTHFD2 promotes basal and IFN-γ-stimulated PD-L1 expression, which is necessary for tumourigenesis in vivo. Moreover, IFN-γ stimulates MTHFD2 through the AKT-mTORC1 pathway. Meanwhile, MTHFD2 drives the folate cycle to sustain sufficient uridine-related metabolites including UDP-GlcNAc, which promotes the global O-GlcNAcylation of proteins including cMYC, resulting in increased cMYC stability and PD-L1 transcription. Consistently, the O-GlcNAcylation level positively correlates with MTHFD2 and PD-L1 in pancreatic cancer patients. These findings uncover a non-metabolic role for MTHFD2 in cell signalling and cancer biology.


Subject(s)
Aminohydrolases/genetics , B7-H1 Antigen/genetics , Carcinogenesis/genetics , Gene Expression Regulation, Neoplastic , Methylenetetrahydrofolate Dehydrogenase (NADP)/genetics , Multifunctional Enzymes/genetics , Pancreatic Neoplasms/genetics , Protein Processing, Post-Translational , T-Lymphocytes, Cytotoxic/immunology , Aminohydrolases/antagonists & inhibitors , Aminohydrolases/immunology , Animals , B7-H1 Antigen/antagonists & inhibitors , B7-H1 Antigen/immunology , Carcinogenesis/immunology , Carcinogenesis/pathology , Cell Line, Tumor , Embryo, Mammalian , Fibroblasts/immunology , Fibroblasts/pathology , Folic Acid/immunology , Folic Acid/metabolism , Humans , Male , Mechanistic Target of Rapamycin Complex 1/genetics , Mechanistic Target of Rapamycin Complex 1/immunology , Methylenetetrahydrofolate Dehydrogenase (NADP)/antagonists & inhibitors , Methylenetetrahydrofolate Dehydrogenase (NADP)/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Nude , Multifunctional Enzymes/antagonists & inhibitors , Multifunctional Enzymes/immunology , Pancreatic Neoplasms/immunology , Pancreatic Neoplasms/pathology , Primary Cell Culture , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/immunology , Proto-Oncogene Proteins c-myc/antagonists & inhibitors , Proto-Oncogene Proteins c-myc/genetics , Proto-Oncogene Proteins c-myc/immunology , RNA, Small Interfering/genetics , RNA, Small Interfering/immunology , Signal Transduction , T-Lymphocytes, Cytotoxic/pathology , Tumor Burden , Tumor Escape , Uridine Diphosphate N-Acetylglucosamine/metabolism , Xenograft Model Antitumor Assays
7.
Phytomedicine ; 34: 76-84, 2017 Oct 15.
Article in English | MEDLINE | ID: mdl-28899513

ABSTRACT

BACKGROUND: Propolis is a resinous substance collected by honeybees, Apis mellifera, from various plant sources. Having various pharmacological and biological activities, it has been used in folk medicine and complementary therapies since ancient times. PURPOSE: To evaluate the effects and underlying mechanism of the protective effects of the ethanol extract of Chinese propolis (EECP) on L929 cells injured by hydrogen peroxide (H2O2). STUDY DESIGN: The wound healing activities of EECP in L929 cells with H2O2-induced damage were investigated. METHODS: The main components of EECP were analyzed by RP-HPLC, and the free radical scavenging capacity and reducing power were also measured. The effects of EECP on the expression of antioxidant-related genes in fibroblast L929 cells were determined using qRT-PCR and western blotting. RESULTS: EECP had significant protective effects against cell death induced by H2O2 and significantly inhibited the decline of collagen mRNA expression caused by H2O2 in L929 cells. CONCLUSION: EECP induced the expression of antioxidant-related genes, such as HO-1, GCLM, and GCLC, which has great implications for the potential of propolis to alleviate oxidative stress in wound tissues. The protective effects of propolis have great implications for using propolis as a wound healing regent.


Subject(s)
Antioxidants/pharmacology , Propolis/pharmacology , Wound Healing/drug effects , Animals , Bees , Cell Line , Chromatography, High Pressure Liquid , Collagen/metabolism , Fibroblasts/drug effects , Hydrogen Peroxide/metabolism , Mice , Oxidative Stress/drug effects
8.
Pharm Biol ; 54(10): 2220-35, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27049854

ABSTRACT

Context Numerous studies have reported that propolis possesses strong antioxidant activities. However, their antioxidant molecular mechanisms are unclear. Objective We utilize ethanol extracts of Chinese propolis (EECP) as a reference to compare ethanol extracts of Eucalyptus propolis (EEEP) with ethanol extracts of Baccharis propolis (EEBGP) based on their antioxidant capacities and underlying molecular mechanisms. Materials and methods HPLC and chemical analysis are utilized to evaluate compositions and antioxidant activities. ROS-eliminating effects of EEBGP (20-75 µg/mL), EEEP (1.25-3.75 µg/mL) and EECP (1.25-5 µg/mL) are also determined by flow cytometry analysis. Moreover, we compared antioxidant capacities by determining their effects on expressions of antioxidant genes in RAW264.7 cells with qRT-PCR, western blot and confocal microscopy analysis. Results EEBGP mainly contains chlorogenic acid (8.98 ± 0.86 mg/g), kaempferide (11.18 ± 8.31 mg/g) and artepillin C (107.70 ± 10.86 mg/g), but EEEP contains 10 compositions, whereas EECP contains 17 compositions. Meantime, although EEEP shows DPPH (IC50 19.55 ± 1.28), ABTS (IC50 20.0 ± 0.31) and reducing power (2.70 ± 0.08 mmol TE/g) better than EEBGP's DPPH (IC50 43.85 ± 0.54), ABTS (IC50 38.2 ± 0.33) and reducing power (1.53 ± 0.05 mmol TE/g), EEBGP exerts much higher ROS inhibition rate (40%) than EEEP (under 20%). Moreover, EEBGP strengthen antioxidant system by activating p38/p-p38 and Erk/p-Erk kinase via accelerating nucleus translocation of Nrf2. EEEP and EECP improve antioxidant gene expression only via Erk/p-Erk kinase-Nrf2 signalling pathway. Discussion and conclusion EEBGP and EEEP exert antioxidant activities via different molecular mechanisms, which may depend on chemical compositions.


Subject(s)
Antioxidants/pharmacology , Baccharis , Ethanol/chemistry , Eucalyptus , Macrophages/drug effects , Oxidative Stress/drug effects , Phenols/pharmacology , Propolis/chemistry , Solvents/chemistry , Animals , Antioxidants/isolation & purification , Antioxidants/toxicity , Cell Survival/drug effects , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Extracellular Signal-Regulated MAP Kinases/metabolism , Gene Expression Regulation/drug effects , Macrophages/metabolism , Mice , NF-E2-Related Factor 2/metabolism , Oxidative Stress/genetics , Phenols/isolation & purification , Phenols/toxicity , RAW 264.7 Cells , Reactive Oxygen Species/metabolism , Signal Transduction/drug effects , p38 Mitogen-Activated Protein Kinases/metabolism
9.
Article in English | MEDLINE | ID: mdl-25802536

ABSTRACT

The biological activities of propolis are varied from plant sources and the prominent antioxidant effects of Chinese propolis (poplar type) have been extensively reported. Oxidative stress is associated with inflammation and induces many diseases. In the study, to evaluate antioxidant capacities and clarify the underlying molecular mechanisms of ethanol extracts of Chinese propolis (EECP) and ethanol extracts of poplar gums (EEPG), we analyzed their compositions by HPLC, evaluating their free radical scavenging activities and reducing power by chemical analysis methods. Moreover, we studied the roles of EECP and EEPG on the elimination of ROS and expressions of antioxidant genes (HO-1, TrxR1, GCLM, and GCLC) in RAW264.7 cells. We further investigated the effects of MAPKs on the antioxidant genes expression by specific inhibitors. The nucleus translocation effects of Nrf2 were also measured by confocal microscopy analysis. The results indicated that EECP had higher TPC and FDC values but regarding TFC values were not significant. EECP also possessed more contents of 11 compounds than EEPG. Both phytochemical analysis and cell experiment reflected that EECP exerted stronger antioxidant activities than EEPG. EECP and EEPG enhanced endogenous antioxidant defenses by eliminating reactive oxygen species directly and activating Erk-Nrf2-HO1, GCLM, and TrxR1 signal pathways.

10.
Chem Commun (Camb) ; 47(12): 3457-9, 2011 Mar 28.
Article in English | MEDLINE | ID: mdl-21305081

ABSTRACT

A visible-light response TiO(2) ultrafiltration membrane was fabricated via a weakly alkaline sol-gel method for the first time, and exhibited a cut-off molecular weight of 7500 Da and high pure water flux of 170 L m(-1) h(-1) bar(-1).

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