RESUMO
Surface proteins on the membrane of nano-sized extracellular vesicles (EVs) not only play crucial roles in cell-to-cell communication, but also are specific binding targets for EV detection, isolation and tracking. The low abundance of protein biomarkers on EV surface, the formation of clusters and the complex EV surface network impose significant challenges to the study of EVs. Employing bulky sized affinity ligands, such as antibodies, in the detection and characterization of these vesicles often result in reduced sensitivity of detection or poor quantification of proteins on the EV surface. By virtue of their small size and high specificity, Affibody molecules emerge as a potential alternative to their monoclonal antibody counterparts as robust affinity ligands in EV research. In this study, we present a theoretical framework on the superiority of anti-HER2 Affibodies over anti-HER2 antibodies in labeling and detecting HER2-positive EVs, followed by the demonstration of the advantages of HER2 Affibodies in accessing EV surface and the detection of EVs through multiple types of approaches including fluorescence intensity, colorimetry, and fluorescence polarization. HER2 Affibodies outperformed by 10-fold over three HER2 antibody clones in accessing HER2-positive EVs derived from different human cancer cell lines. Furthermore, HRP-Affibody molecules could detect EVs from cancer cells spiked into human serum with at least a 2-fold higher sensitivity compared with that of their antibody counterparts. In addition, in fluorescence polarization assays in which no separation of free from bound ligand is required, FITC-labeled HER2 Affibodies could sensitively detect HER2-positive EVs with a clinically relevant limit of detection, whilst HER2 antibodies failed to detect EVs in the same conditions. With the demonstrated superiority in accessing and detecting surface targets over bulky-sized antibodies in EVs, Affibodies may become the next-generation of affinity ligands in the precise characterization and quantification of molecular architecture on the surface of EVs.
Assuntos
Técnicas Biossensoriais , Vesículas Extracelulares , Receptor ErbB-2 , Vesículas Extracelulares/química , Humanos , Ligantes , Técnicas Biossensoriais/métodos , Linhagem Celular Tumoral , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologiaRESUMO
Ribosomopathies encompass a spectrum of disorders arising from impaired ribosome biogenesis and reduced functionality. Mutation or dysexpression of the genes that disturb any finely regulated steps of ribosome biogenesis can result in different types of ribosomopathies in clinic, collectively known as ribosomopathy genes. Emerging data suggest that ribosomopathy patients exhibit a significantly heightened susceptibility to cancer. Abnormal ribosome biogenesis and dysregulation of some ribosomopathy genes have also been found to be intimately associated with cancer development. The correlation between ribosome biogenesis or ribosomopathy and the development of malignancies has been well established. This work aims to review the recent advances in the research of ribosomopathy genes among human cancers and meanwhile, to excavate the potential role of these genes, which have not or rarely been reported in cancer, in the disease development across cancers. We plan to establish a theoretical framework between the ribosomopathy gene and cancer development, to further facilitate the potential of these genes as diagnostic biomarker as well as pharmaceutical targets for cancer treatment.
RESUMO
This study introduces a one-pot isothermal amplification assay for ultrasensitive analysis of terminal deoxynucleotidyl transferase (TdT) activity. The system realizes recycled activation of CRISPR/Cas12a, enabling exceptional signal amplification. This approach maximizes the simplicity of the detection method, offering a promising avenue for molecular disease diagnosis.
Assuntos
Sistemas CRISPR-Cas , DNA Nucleotidilexotransferase , Técnicas de Amplificação de Ácido Nucleico , DNA Nucleotidilexotransferase/metabolismo , Sistemas CRISPR-Cas/genética , HumanosRESUMO
BACKGROUND: Ganoderma lucidum ( G . lucidum ) is a traditional Chinese herbal medicine that has shown potential as an alternative adjuvant therapy for cancer patients. However, the mechanisms and adjuvant therapeutic effects of G . lucidum in cancer treatment remain unclear. METHODS: In this work, G . lucidum spore oil (GanoOil), a newly developed oily G . lucidum spore extract was used to investigate the mechanisms and adjuvant therapeutic effects of GanoOil in conjunction with the chemotherapeutic drug cyclophosphamide (CTX) for preventing breast cancer metastasis. RESULTS: In the model of lung metastasis, orally administered GanoOil increased the population of CD8 + T cells and interleukin (IL)-6 cytokine levels in mouse blood, whereas also enhancing the activity of natural killer cells in the spleen. Furthermore, the combination of GanoOil and CTX effectively suppressed the lung metastasis of circulating breast cancer cells, alleviated CTX-induced weight loss, and reduced the ratio of lung and spleen weight to body weight in mice. Moreover, high concentrations of GanoOil exhibited no significant toxicity or side effects in both in vitro and in vivo experiments. CONCLUSION: In conclusion, GanoOil is a safe drug that can enhance immune activity in mice to achieve therapeutic effects on cancer, and can also synergistically inhibit tumor metastasis with CTX.
Assuntos
Neoplasias da Mama , Neoplasias Pulmonares , Segunda Neoplasia Primária , Reishi , Humanos , Animais , Camundongos , Feminino , Neoplasias da Mama/patologia , Esporos Fúngicos , Ciclofosfamida/farmacologia , Ciclofosfamida/uso terapêutico , Interleucina-6 , Neoplasias Pulmonares/prevenção & controleRESUMO
Hybridization chain reaction (HCR) based enzyme-free amplification techniques have recently been developed for the visualization of intracellular messenger RNA (mRNA). However, the slow kinetics and potential interference with the intricate biological environments hinder its application in the clinic and in vivo. Herein, we designed a nanofirecracker probe-based strategy using intramolecular hybridization chain reaction (IHCR) amplifier for rapid, efficient, sensitive, specific detection and imaging of survivin mRNA both in vitro and vivo. Two probes, HP1 and HP2, in IHCR were simultaneously incorporated into a DNA nanowire scaffolds to bring HP1 and HP2 to close proximity on the assembled nanowire scaffolds. Empowered by the DNA nanowire scaffolds and spatial confinement effect, the nanofirecracker probe-based IHCR sensing system exhibited improved biostability, accelerated reaction kinetics, and enhanced signal amplification. This new strategy has been successfully applied to imaging mRNA in both cultured cells and in mice. Importantly, this novel sensing method was capable of detecting survivin mRNA in clinical blood samples from subjects with colorectal cancer. Thus, this novel nanofirecracker probe-based IHCR strategy holds great potential in advancing both biomedical research and in molecular diagnostics.
Assuntos
Técnicas Biossensoriais , Humanos , Animais , Camundongos , RNA Mensageiro/genética , Survivina/genética , Técnicas Biossensoriais/métodos , Hibridização de Ácido Nucleico/métodos , DNA/genética , Proteínas Cromossômicas não Histona/genéticaRESUMO
Over the past decade, there has been a significant expansion in the development of plant-derived extracellular nanovesicles (EVs) as an effective drug delivery system for precision therapy. However, the lack of effective methods for the isolation and characterization of plant EVs hampers progress in the field. To solve a challenge related to systemic separation and characterization in the plant-derived EV field, herein, we report the development of a simple 3D inner filter-based method that allows the extraction of apoplastic fluid (AF) from blueberry, facilitating EV isolation as well as effective downstream applications. Class I chitinase (PR-3) was found in blueberry-derived EVs (BENVs). As Class I chitinase is expressed in a wide range of plants, it could serve as a universal marker for plant-derived EVs. Significantly, the BENVs exhibit not only higher drug loading capacity than that reported for other EVs but also possess the ability to modulate the release of the proinflammatory cytokine IL-8 and total glutathione in response to oxidative stress. Therefore, the BENV is a promising edible multifunctional nano-bio-platform for future immunomodulatory therapies.
RESUMO
Alzheimer's disease (AD) continues to be a major global health challenge, and the recent approval of Aduhelm and Leqembi has opened new avenues for its treatment. Small-molecule inhibitors targeting Aß aggregation hold promise as an alternative to monoclonal antibodies. In this study, we evaluated the ability of berbamine hydrochloride (BBMH), a member of the bisbenzylisoquinoline alkaloids, to reduce Aß aggregation and cytotoxicity. Thioflavin T kinetics, circular dichroism spectroscopy, and atomic force microscopy results indicated that BBMH effectively inhibited Aß aggregation. Surface plasmon resonance and molecular docking results further revealed that BBMH could bind to Aß fibrils, thereby hindering the aggregation process. This physical picture has been confirmed in a quantitative way by chemical kinetics analysis, which showed BBMH tends to bind with the fibril ends and thus prevents the transition from protofibrils to mature fibrils as well as the elongation process. Additionally, our MTT results showed that BBMH was able to reduce the cytotoxicity of Aß40 on N2a cells. Our results demonstrate, for the first time, the potential of BBMH to inhibit Aß aggregation and cytotoxicity, offering a promising direction for further research and drug development efforts in the fight against Alzheimer's disease.
Assuntos
Doença de Alzheimer , Benzilisoquinolinas , Humanos , Peptídeos beta-Amiloides/química , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Simulação de Acoplamento Molecular , Fragmentos de Peptídeos/toxicidade , Fragmentos de Peptídeos/química , Benzilisoquinolinas/farmacologia , Amiloide/químicaRESUMO
Wnt signaling plays numerous functions in cancer, from primary transformation and tumor growth to metastasis. In addition to these cancer cell-intrinsic functions, Wnt signaling emerges to critically control cross-communication among cancer cells and the tumor microenvironment (TME). Here, we summarize the evidence that not only multiple cancer cell types, but also cells constituting the TME 'speak the Wnt language'. Fibroblasts, macrophages, endothelia, and lymphocytes all use the Wnt language to convey messages to and from cancer cells and among themselves; these messages are important for tumor progression and fate. Decoding this language will advance our understanding of tumor biology and unveil novel therapeutic avenues.
Assuntos
Neoplasias , Microambiente Tumoral , Humanos , Neoplasias/patologia , Macrófagos/metabolismo , Via de Sinalização Wnt , IdiomaRESUMO
Developing highly efficient and reliable methods for simultaneous imaging of microRNAs in living cells is often appealed to understanding their synergistic functions and guiding the diagnosis and treatment of human diseases, such as cancers. In this work, we rationally engineered a four-arm shaped nanoprobe that can be stimuli-responsively tied into a Figure-of-Eight nanoknot via spatial confinement-based dual-catalytic hairpin assembly (SPACIAL-CHA) reaction and applied for accelerated simultaneous detection and imaging of different miRNAs in living cells. The four-arm nanoprobe was facilely assembled from a cross-shaped DNA scaffold and two pairs of CHA hairpin probes (21HP-a and 21HP-b for miR-21, while 155HP-a and 155HP-b for miR-155) via the "one-pot" annealing method. The DNA scaffold structurally provided a well-known spatial-confinement effect to improve the localized concentration of CHA probes and shorten their physical distance, resulting in an enhanced intramolecular collision probability and accelerating the enzyme-free reaction. The miRNA-mediated strand displacement reactions can rapidly tie numerous four-arm nanoprobes into Figure-of-Eight nanoknots, yielding remarkably dual-channel fluorescence proportional to the different miRNA expression levels. Moreover, benefiting from the nuclease-resistant DNA structure based on the unique arched DNA protrusions makes the system ideal for operating in complicated intracellular environments. We have demonstrated that the four-arm-shaped nanoprobe is superior to the common catalytic hairpin assembly (COM-CHA) in stability, reaction speed, and amplification sensitivity in vitro and living cells. Final applications in cell imaging have also revealed the capacity of the proposed system for reliable identification of cancer cells (e.g., HeLa and MCF-7) from normal cells. The four-arm nanoprobe shows great potential in molecular biology and biomedical imaging with the above advantages.
Assuntos
Técnicas Biossensoriais , MicroRNAs , Humanos , MicroRNAs/genética , DNA/química , Células HeLa , Catálise , Fluorescência , Técnicas Biossensoriais/métodos , Limite de DetecçãoRESUMO
MicroRNAs (miRNAs) play an important biomarker in various biological processes, especially cancer related, yet economic, simple, sensitive and specific methods for miRNA determination are still challenging. In this study, we have developed stepwise-strand displacement amplification (S-SDA)-based colorimetric sensing platform for let-7a miRNA detection in clinical serum samples. Our results demonstrated that the developed S-SDA-based method shows high sensitivity with a detection limit of 63.2 pM and a naked eye detection limit of 0.1 nM. Moreover, the S-SDA amplifier is able to discriminate target miRNAs from their mutants with high accuracy and specificity. With its high sensitivity and selectivity, this method successfully identified healthy individuals from patients with colon cancer by detecting let-7a miRNAs in serum. We believe the colorimetric analysis method will provide a new paradigm for the detection of miRNA with different abundance and show great potential for clinical application in biomedical analysis and early clinical diagnosis.
RESUMO
Regulation of tumor cell death is a fundamental mechanism for tumor treatment. However, most tumors are resistant to cell death. Triggering inflammatory cell death, pyroptosis, may provide a new view of enhancing tumor cell death. Here we report a new role of Ganoderma lucidum extract (GLE) in pyroptotic cell death. Treatment with GLE (50-200 µg/mL) significantly elevated reactive oxygen species (ROS) levels and caused pyroptotic cell death in breast cancer cells. Mechanistically, GLE activates caspase 3 and further cleaves the gasdermin E (GSDME) protein to form pores on the cell membrane, releasing massive amounts of inflammatory factors in breast cancer cells. We also showed that GLE enhanced antitumor immune responses by substantially increasing the subsets of natural killer (NK) and CD8+T cells in the peripheral immune system and tumor microenvironment. In addition, GLE destroys multiple steps of tumor metastasis, including adhesion, migration, invasion, colonization, and angiogenesis. Collectively, these results suggest that GLE provides a potential approach for breast cancer treatment, which may complement chemotherapy or immunotherapy for cancer metastasis.
Assuntos
Neoplasias da Mama , Reishi , Humanos , Feminino , Piroptose , Microambiente TumoralRESUMO
The assay performance of electrochemical DNA (E-DNA) sensors is deeply influenced by the state of DNA probes immobilized on electrode. Moreover, the immobilization procedures for DNA probes are tedious and vary according to the probes and analytes. In this work, we find that the adsorption layers of bovine serum albumin (BSA) on gold electrode (AuE) possess a size exclusion effect to distinguish between single-stranded (-ss) DNA probes and the DNA fragments generated from enzymatic digestion of ssDNA probes. In detail, the BSA layers act as a gatekeeper that hinders the adsorption of a ssDNA probe on AuE but permits the DNA fragments with much smaller sizes to pass through the adsorption layers and adsorb on AuE. This finding is developed into a novel E-DNA sensor for microRNA (miRNA) detection by coupling with duplex-specific nuclease (DSN)-assisted target recycling strategy. The ssDNA probe in solution phase is enzymatically digested during the DSN-assisted target recycling process initiated by target miRNA-21, generating plenty of DNA fragments. The adsorption of these DNA fragment on BSA/AuE is permitted, which arouses electrochemical signals after binding with [Ru(NH3)6]3+ to indicate the recognition of miRNA-21. The developed E-DNA sensor possesses a wide calibration range from 0.001 to 100 pM and a low detection limit of 0.48 fM. Significantly, accurate evaluation of miRNA-21 expression levels in cancer cell lines and non-small-cell lung carcinomas (NSCLC) serum samples are successfully achieved using the developed method. This work provides a new mechanism for constructing sensitive E-DNA sensor without tedious probe immobilization procedures.
Assuntos
Técnicas Biossensoriais , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , MicroRNAs , Humanos , Adsorção , DNA , DNA de Cadeia Simples , Soroalbumina Bovina , EndonucleasesRESUMO
The microRNAs (miRNAs) play a critical role in many biological processes and are essential biomarkers for diagnosing disease. However, the sensitive and specific quantification of microRNAs (miRNAs) expression in living cells still faces a huge challenge. Our study designed a multifunctional linear DNA nanostructure (MLN) as a carrier of molecular beacons (MB-21) for detecting and intracellular imaging miRNA-21. The MLN-MB consists of three parts: aptamer, MLN, and MB-21. The aptamer (AS1411) could media MLN-MB enter live cells without additional transfection reagents. Once inside the cells, the intracellular miRNA-21 could hybridize the MB-21s, resulting in significantly enhanced fluorescence signals. The whole process was enzyme-free, autonomous, and continuous, which avoided the necessity of adding external fuel strands or enzymes. We demonstrated that the MLN-MB could be used to screen the miRNA-21 with a detection limit of 320 pM in a short time (10 min) and show high specificity toward miRNA-21 against other miRNAs. Moreover, the proposed MLN-MB could detect the miRNA-21 in complex matrixes stably. With its outstanding stability, dual recognition, and biocompatibility, MLN-MB is capable of delivering into living cells to identify specific cancer cells. Therefore, our sensing approach, with high sensitivity, specificity, and simplicity advantages, holds great potential for early cancer diagnosis.
Assuntos
MicroRNAs , DNA/genéticaRESUMO
Endoxifen (ENDX) is an active metabolite of tamoxifen (TAM), a drug commonly used for the treatment of estrogen receptor-positive breast cancer and metabolized by CYP2D6. Genetic or drug-induced reductions in CYP2D6 activity decrease plasma ENDX concentrations and TAM efficacy. It was proposed that direct oral administration of ENDX would circumvent the issues related to metabolic activation of TAM by CYP2D6 and increase patient response. Here, we characterized the pharmacokinetics and oral bioavailability of ENDX in female rats and dogs. Additionally, ENDX exposure was compared following equivalent doses of ENDX and TAM. ENDX exposure was 100-fold and 10-fold greater in rats and dogs, respectively, with ENDX administration compared with an equivalent dose of TAM. In single-dose administration studies, the terminal elimination half-life and plasma clearance values were 6.3 hours and 2.4 L/h per kg in rats given 2 mg/kg i.v. ENDX and 9.2 hours and 0.4 L/h/kg in dogs given 0.5 mg/kg i.v. ENDX, respectively. Plasma concentrations above 0.1 µM and 1 µM ENDX were achieved with 20-mg/kg and 200-mg/kg doses in rats, and concentrations above 1 µM and 10 µM were achieved with 15-mg/kg and 100-mg/kg doses in dogs. Oral absorption of ENDX was linear in rats and dogs, with bioavailability greater than 67% in rats and greater than 50% in dogs. In repeated-dose administration studies, ENDX peak plasma concentrations reached 9 µM in rats and 20 µM in dogs following four daily doses of 200 mg/kg or 30 mg/kg ENDX, respectively. The results indicate that ENDX has high oral bioavailability, and therapeutic concentrations were maintained after repeated dosing. Oral dosing of ENDX resulted in substantially higher ENDX concentrations than a similar dose of TAM. These data support the ongoing development of ENDX to overcome the limitations associated with CYP2D6-mediated metabolism of TAM in humans. SIGNIFICANCE STATEMENT: This study presents for the first time the pharmacokinetics and bioavailability of endoxifen and three key tamoxifen metabolites following repeated oral dosing in female rats and dogs. This study reports that endoxifen has high oral bioavailability, and therapeutic concentrations were maintained after repeated dosing. On the basis of these data, Z-endoxifen (Z-ENDX) was developed as a drug based upon the hypothesis that oral administration of Z-ENDX would overcome the limitations of CYP2D6 metabolism required for full metabolic activation of tamoxifen.
Assuntos
Neoplasias da Mama , Citocromo P-450 CYP2D6 , Humanos , Feminino , Cães , Ratos , Animais , Citocromo P-450 CYP2D6/metabolismo , Disponibilidade Biológica , Tamoxifeno , Neoplasias da Mama/metabolismo , Antineoplásicos Hormonais/farmacocinéticaRESUMO
Doxorubicin is the most frequently used chemotherapeutic agent for the treatment of hepatocellular carcinoma. However, one major obstacle to the effective management of liver cancer is the drug resistance derived from the cancer stem cells. Herein, we employed a CD133 aptamer for targeted delivery of doxorubicin into liver cancer stem cells to overcome chemoresistance. Furthermore, we explored the efficacy of autophagy inhibition to sensitize liver cancer stem cells to the treatment of CD133 aptamer-doxorubicin conjugates based on the previous observation that doxorubicin contributes to the survival of liver cancer stem cells by activating autophagy. The kinetics and thermodynamics of aptamer-doxorubicin binding, autophagy induction, cell apoptosis, and self-renewal of liver cancer stem cells were studied using isothermal titration calorimetry, Western blot analysis, annexin V assay, and tumorsphere formation assay. The aptamer-cell binding andintracellular accumulation of doxorubicin were quantified via flow cytometry. CD133 aptamer-guided delivery of doxorubicin resulted in a higher doxorubicin concentration in the liver cancer stem cells. The combinatorial treatment strategy of CD133 aptamer-doxorubicin conjugates and an autophagy inhibitor led to an over 10-fold higher elimination of liver cancer stem cells than that of free doxorubicin in vitro. Future exploration of cancer stem cell-targeted delivery of doxorubicin in conjunction with autophagy inhibition in vivo may well lead to improved outcomes in the treatment of hepatocellular carcinoma.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Doxorrubicina/química , Células-Tronco Neoplásicas/metabolismo , Autofagia , Neoplasias Hepáticas/metabolismo , Linhagem Celular TumoralRESUMO
OBJECTIVES: Primary tumor treatment through surgical resection and adjuvant therapy has been extensively studied, but there is a lack of effective strategies and drugs for the treatment of tumor metastases. Here, we describe a functional product based on a combination of compounds, which can be used as an adjuvant therapy and has well-known mechanisms for inhibiting cancer metastases, improving anti-cancer treatment, and enhancing immunity and antioxidant capacity. Our designed combination, named MVBL, consists of four inexpensive compounds: L-selenium-methylselenocysteine (MSC), D-|α|-tocopheryl succinic acid (VES), ß|-carotene (ß|-Ca), and L-lysine (Lys). METHODS: The effects of MVBL on cell viability, cell cycle, cell apoptosis, cell migration, cell invasion, reactive oxygen species (ROS), and paclitaxel (PTX)-combined treatment were studied in vitro. The inhibition of tumor metastasis, antioxidation, and immune enhancement capacity of MVBL were determined in vivo. RESULTS: MVBL exhibited higher toxicity to tumor cells than to normal cells. It did not significantly affect the cell cycle of cancer cells, but increased their apoptosis. Wound healing, adhesion, and transwell assays showed that MVBL significantly inhibited tumor cell migration, adhesion, and invasion. MVBL sensitized MDA-MB-231 breast cancer cells to PTX, indicating that it can be used as an adjuvant to enhance the therapeutic effect of chemotherapy drugs. In mice, experimental data showed that MVBL inhibited tumor metastasis, prolonged their survival time, and enhanced their antioxidant capacity and immune function. CONCLUSIONS: This study revealed the roles of MVBL in improving immunity and antioxidation, preventing tumor growth, and inhibiting metastasis in vitro and in vivo. MVBL may be used as an adjuvant drug in cancer therapy for improving the survival and quality of life of cancer patients.
Assuntos
Neoplasias , beta Caroteno , Camundongos , Animais , Lisina/farmacologia , Antioxidantes/farmacologia , Qualidade de Vida , Paclitaxel/farmacologia , Apoptose , alfa-Tocoferol , Succinatos/farmacologia , Linhagem Celular Tumoral , Proliferação de CélulasRESUMO
The war against cancer traces back to the signature event half-a-century ago when the US National Cancer Act was signed into law. The cancer crusade costs trillions with disappointing returns, teasing the possibility of a new breakthrough. Cure for cancer post-metastases still seems tantalisingly out of reach. Once metastasized, cancer-related death is extremely difficult, if not impossible, to be reversed. Here we present cancer pre-metastasis chemoprevention strategy that can prevent circulating tumour cells (CTCs) from initiating metastases safely and effectively, and is disparate from the traditional cancer chemotherapy and cancer chemoprevention. Deep learning of the biology of CTCs and their disseminating organotropism, complexity of their adhesion to endothelial niche reveals that if the adhesion of CTCs to their metastasis niche (the first and the most important part in cancer metastatic cascade) can be pharmaceutically interrupted, the lethal metastatic cascade could be prevented from getting initiated. We analyse the key inflammatory and adhesive factors contributing to CTC adhesion/germination, provide pharmacological fundamentals for abortifacients to intervene CTC adhesion to the distant metastasis sites. The adhesion/inhibition ratio (AIR) is defined for selecting the best cancer metastasis chemopreventive candidates. The successful development of such new therapeutic modalities for cancer metastasis chemoprevention has great potential to revolutionise the current ineffective post-metastasis treatments.
Assuntos
Células Neoplásicas Circulantes , Quimioprevenção , Humanos , Células Neoplásicas Circulantes/patologiaRESUMO
Metastasis is the leading cause of cancer-related death and a critical challenge in improving cancer treatment today. Circulating tumor cells (CTCs) adhesion to and across the vascular endothelium are critical steps in the establishment of micrometastatic foci away from the primary tumor. Therefore, we believe that interrupting CTCs adhesion to endothelium and transendothelial migration may efficiently prevent cancer metastasis. Fucoxanthin (Fx) is an algal carotenoid widely distributed in brown algae, macroalgae, and diatoms. Previous studies have found that Fx has various pharmacological activities, including antidiabetic, antioxidant, anti-inflammatory, anti-obesity, antimalarial, anticancer, and so on. However, it remains unclear whether Fx has a preventive effect on cancer metastasis. Here, we found that Fx interrupts breast cancer cells MCF-7 adhesion to endothelium and transendothelial migration, thus inhibiting CTCs-based pulmonary metastasis in vivo. The hetero-adhesion assay showed that Fx significantly inhibited the expression of inflammatory factor-induced cell adhesion molecules (CAMs) and the resulting adhesion between MCF-7 cells and endothelial cells. The wound-healing and transwell assays showed that Fx significantly inhibited the motility, invasion, and transendothelial migration abilities of MCF-7 cells. However, the same concentration of Fx did not significantly alter the cell viability, cell cycle, apoptosis, and ROS of breast cancer cells, thus excluding the possibility that Fx inhibits MCF-7 cell adhesion and transendothelial migration through cytotoxicity. Mechanistically, Fx inhibits the expression of CAMs on endothelial cells by inhibiting the NF-кB signaling pathway by down-regulating the phosphorylation level of IKK-α/ß, IкB-α, and NF-кB p65. Fx inhibits transendothelial migration of MCF-7 cells by inhibiting Epithelial-to-mesenchymal transition (EMT), PI3K/AKT, and FAK/Paxillin signaling pathways. Moreover, we demonstrated that Fx significantly inhibits the formation of lung micrometastatic foci in immunocompetent syngeneic mouse breast cancer metastasis models. We also showed that Fx enhances antitumor immune responses by substantially increasing the subsets of cytotoxic T lymphocytes in the peripheral immune system. This new finding provides a basis for the application of Fx in cancer metastatic chemoprevention and suggests that interruption of the CTCs adhesion to endothelium and transendothelial migration may serve as a new avenue for cancer metastatic chemoprevention.
RESUMO
The Red-headed Krait (Bungarus flaviceps) is a medically important venomous snake species in Southeast Asia, while there is no specific antivenom available for its envenoming. This study investigated the venom composition through a decomplexation proteomic approach, and examined the immunoreactivity as well as cross-neutralization efficacy of two hetero-specific krait antivenoms, Bungarus candidus Monovalent Antivenom (BcMAV) and Bungarus fasciatus Monovalent Antivenom (BfMAV), against the venom of B. flaviceps from Peninsular Malaysia. A total of 43 non-redundant proteoforms belonging to 10 toxin families were identified in the venom proteome, which is dominated by phospholipases A2 including beta-bungarotoxin lethal subunit (56.20 % of total venom proteins), Kunitz-type serine protease inhibitors (19.40 %), metalloproteinases (12.85 %) and three-finger toxins (7.73 %). The proteome varied in quantitative aspect from the earlier reported Indonesian (Sumatran) sample, suggesting geographical venom variation. BcMAV and BfMAV were immunoreactive toward the B. flaviceps venom, with BcMAV being more efficacious in immunological binding. Both antivenoms cross-neutralized the venom lethality with varying efficacy, where BcMAV was more potent than BfMAV by ~13 times (normalized potency: 38.04 mg/g vs. 2.73 mg/g, defined as the venom amount completely neutralized by one-gram antivenom protein), supporting the potential utility of BcMAV for para-specific neutralization against B. flaviceps venom.
Assuntos
Antivenenos , Bungarus , Animais , Antivenenos/química , Antivenenos/farmacologia , Bungarotoxinas/metabolismo , Bungarotoxinas/toxicidade , Bungarus/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Peçonhas/metabolismoRESUMO
Mifepristone (RU486) is a chemical contraceptive marketed in more than 55 countries and used by hundreds of millions of women worldwide. Current studies reported its uses by both genders for a safe and long-term psychotic depression and particularly for traditional cancer chemotherapy. Here, we investigated the multidisciplinary data from recent large epidemiological chemoprevention studies for long-term use of oral contraceptives to reduce cancer risk, and from the unsuccessful clinical trials of mifepristone used as a post-metastatic anticancer drug, and elucidated the similarities and differences in cellular and molecular processes between embryonic implantation to endometrium and adhesion/invasion of circulating tumor cells (CTCs) to vascular endothelium. The deep analyses provide a stronger scientific basis for repurposing abortifacients for safe and effective cancer metastatic chemoprevention. Initiation of such cancer drug development strategy represents a paradigm shift from traditional post-metastasis treatments to novel pre-metastasis chemoprevention.