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1.
Cancer Immunol Immunother ; 73(5): 88, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554175

RESUMEN

BACKGROUND: Prenatal inflammation exposure (PIE) can increase the disease susceptibility in offspring such as lung cancer. Our purpose was to investigate the mechanisms of PIE on lung cancer. METHODS: Prenatal BALB/c mice were exposed to lipopolysaccharide (LPS), and then, their offspring were intraperitoneally instilled with urethane to establish the two-stage lung cancer carcinogenesis model. At the 48 weeks of age, the offspring mice were killed and lung tissues were collected for HE, immunohistochemistry, immunofluorescence, and Luminex MAGPIX®-based assays. CD11b + F4/80 + tumor-associated macrophages (TAMs) were sorted out from lung tumor tissues by cell sorting technique. Flow cytometry was employed to evaluate the extent of M2-like polarization of TAMs and PD-L1 expression. RESULTS: The offspring of PIE mice revealed more lung lesion changes, including atypical hyperplasia and intrapulmonary metastases. The number of lung nodules, lung organ index, and PCNA, MMP-9 and Vimentin positive cells in lung tissue of PIE group were higher than those of Control group. The increases of mRNA encoding M2 macrophage markers and cytokines in offspring of prenatal LPS-treated mice confirmed the induced effect of PIE on macrophage polarization. Additionally, PIE treatment increased the percentage of CD163 + CD206 + cells in the sorted TAMs. Importantly, endoplasmic reticulum (ER) stress-markers like GRP78/BIP and CHOP, p-IRE1α and XBP1s, and PD-L1 were up-regulated in TAMs from PIE group. Besides, we also observed that IRE1α inhibitor (KIRA6) reversed the M2-like TAMs polarization and metastasis induced by PIE. CONCLUSIONS: IRE1α/XBP1-mediated M2-like TAMs polarization releases the pro-tumorigenic cytokines and PD-L1 expression, which may be the regulatory mechanism of accelerating lung cancer in offspring of mice undergoing PIE.


Asunto(s)
Neoplasias Pulmonares , Animales , Ratones , Neoplasias Pulmonares/patología , Endorribonucleasas/metabolismo , Endorribonucleasas/farmacología , Macrófagos Asociados a Tumores/metabolismo , Antígeno B7-H1/metabolismo , Lipopolisacáridos/farmacología , Transducción de Señal , Proteínas Serina-Treonina Quinasas/metabolismo , Carcinogénesis , Citocinas , Inflamación , Microambiente Tumoral/genética
2.
Metab Eng ; 82: 250-261, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38428728

RESUMEN

Gastrodin, a phenolic glycoside, is a prominent component of Gastrodia elata, which is renowned for its sedative, hypnotic, anticonvulsant, and neuroprotective activities. Engineering heterologous production of plant natural products in microbial host represents a safe, cost-effective, and scalable alternative to plant extraction. Here, we present the construction of an engineered Yarrowia lipolytica yeast that achieves a high-titer production of gastrodin. We systematically refactored the yeast genome by enhancing the flux of the shikimate pathway and optimizing the glucosyl transfer system. We introduced more than five dozen of genetic modifications onto the yeast genome, including enzyme screening, alleviation of rate-limiting steps, promoter selection, genomic integration site optimization, downregulation of competing pathways, and elimination of gastrodin degradation. Meanwhile, we developed a Copper-induced Antisense-Transcriptional Regulation (CATR) tool. The developed CATR toolkit achieved dynamic repression and activation of violacein synthesis through the addition of copper in Y. lipolytica. This strategy was further used to dynamically regulate the pyruvate kinase node to effectively redirect glycolytic flux towards the shikimate pathway while maintaining cell growth at proper rate. Taken together, these efforts resulted in 9477.1 mg/L of gastrodin in shaking flaks and 13.4 g/L of gastrodin with a yield of 0.149 g/g glucose in a 5-L bioreactor, highlighting the potential for large-scale and sustainable production of gastrodin from microbial fermentation.


Asunto(s)
Cobre , Yarrowia , Ácido Shikímico , Glucósidos , Alcoholes Bencílicos , Yarrowia/genética
3.
Bioorg Med Chem Lett ; 99: 129613, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38224754

RESUMEN

A series of bis-isatin conjugates with lysine linker were synthesized with the aim of probing their antiproliferative potential. All the newly synthesized derivatives (0-100 µM) were first screened against liver cancer cell lines(Huh1, H22, Huh7, Hepa1-6, HepG2, Huh6 and 97H) using CCK-8 assay. Results indicated that the derivative 4d exhibited the most potent activity against Huh1 (IC50 = 17.13 µM) and Huh7(IC50 = 8.265 µM). In vivo anti-tumor study showed that compound 4d effectively inhibited tumor growth in Huh1-induced xenograft mouse model; the anti-tumor effect of compound 4d (15 mg/kg) was comparable with sorafenib (20 mg/kg). H&E staining analysis and routine blood test and blood serum biochemistry examination was performed to confirm the safety of compound 4d in xenograft models. The mechanism of action of 4d on tumor growth inhibition was further investigated by RNA-Seq analysis, which indicates a positive regulation of autophagy signaling pathway, which was further confirmed with key biomarker expression of autophagy after 4d treatment. Our results suggest that the bis-isatin conjugate compound 4d is a promising tumor inhibitory agent for some liver cancer.


Asunto(s)
Antineoplásicos , Isatina , Neoplasias Hepáticas , Humanos , Animales , Ratones , Línea Celular Tumoral , Isatina/química , Ensayos de Selección de Medicamentos Antitumorales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Proliferación Celular , Relación Estructura-Actividad , Estructura Molecular
4.
BMC Public Health ; 24(1): 758, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38468219

RESUMEN

BACKGROUND: The relationship between the triglyceride glucose (TyG) index and osteoarthritis (OA) remains unclear. The objective of this study was to examine potential associations between an elevated TyG index and an increased risk of OA prevalence. METHODS: 3,921 participants with OA from the National Health and Nutrition Examination Survey (2015-2020) were included in this study. Participants were categorized into quartiles based on TyG index, which was determined using the formula: Ln [triglyceride (mg/dL) fasting blood glucose (mg/dL)/2]. Weighted multivariable regression, subgroup analyses, and threshold effect analyses were performed to calculate the independent association between TyG index and OA. RESULTS: A total of 25,514 people were enrolled, with a mean TyG index of 8.48 ± 0.65. The results of multivariable logistic regression analysis after full adjustment showed a significant association between higher TyG index values and an increased risk of OA. Specifically, each incremental unit increase in the TyG index was associated with a 634% higher risk of OA [OR = 7.34; 95% CI: 2.25, 23.93; p = 0.0010]. Based on interaction tests, age, gender, BMI, and smoking status did not significantly affect the relationship between the TyG index and OA, while diabetes showed a stronger positive correlation between the TyG index and OA. CONCLUSION: An increased risk of OA was associated with a higher TyG index. TyG could be a valuable predictor of OA and offer novel perspectives on the assessment and treatment of OA.


Asunto(s)
Glucosa , Osteoartritis , Humanos , Encuestas Nutricionales , Osteoartritis/epidemiología , Triglicéridos , Glucemia
5.
Small ; 18(41): e2202161, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36089650

RESUMEN

It is highly desirable to design a single modality that can simultaneously trigger apoptosis and ferroptosis to efficiently eliminate tumor progression. Herein, a nanosystem based on the intrinsic properties of tumor microenvironment (TME) is designed to achieve tumor control through the simultaneous induction of ferroptosis and apoptosis. CuCP molecules are encapsulated in a liposome-based nanosystem to assemble into biocompatible and stable CuCP nanoparticles (CuCP Lipo NPs). This nanosystem intrinsically possesses nanozymatic activity and photothermal characteristics due to the property of Cu atoms and the structure of CuCP Lipo NPs. It is demonstrated that the synergistic strategy increases the intracellular lipid-reactive oxides species, induces the occurrence of ferroptosis and apoptosis, and completely eradicates the tumors in vivo. Proteomics analysis further discloses the key involved proteins (including Tp53, HMOX1, Ptgs2, Tfrc, Slc11a2, Mgst2, Sod1, and several GST family members) and pathways (including apoptosis, ferroptosis, and ROS synthesis). Conclusively, this work develops a strategy based on one nanosystem to synergistically induce ferroptosis and apoptosis in vivo for tumor suppression, which holds great potential in the clinical translation for tumor therapy.


Asunto(s)
Ferroptosis , Nanopartículas , Neoplasias , Apoptosis , Línea Celular Tumoral , Ciclooxigenasa 2 , Lípidos , Liposomas , Nanopartículas/química , Neoplasias/terapia , Óxidos , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa-1 , Microambiente Tumoral
6.
J Opt Soc Am A Opt Image Sci Vis ; 38(1): 115-123, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33362159

RESUMEN

Fork-shaped fringes are formed for off-axis interference between two oblique-incident vortex beams. New formulas considering various parameters [such as the angles between two vortex beams and their topological charges (TCs)] are established to describe all kinds of fork-shaped fringes. An improved Mach-Zehnder interferometer is employed to investigate these interference fringes. Experimental measurements are consistent with numerical simulations by using our formulas. Our results broaden the understanding of the off-axis interference between two vortex beams, and can be applied to detect the TCs' sign and value of an unknown vortex beam, especially large-value TCs.

7.
Artículo en Inglés | MEDLINE | ID: mdl-32457108

RESUMEN

Novel antiparasitic activity was observed for the antifungal occidiofungin. It efficaciously and irreversibly inhibited the zoonotic enteric parasite Cryptosporidium parvumin vitro with limited cytotoxicity (50% effective concentration [EC50] = 120 nM versus 50% cytotoxic concentration [TC50] = 988 nM), and its application disrupted the parasite morphology. This study expands the spectrum of activity of a glycolipopeptide named occidiofungin. Occidiofungin has poor gastrointestinal tract absorption properties, supporting future investigations into its potential activities on other enteric parasites.


Asunto(s)
Criptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Antifúngicos/farmacología , Antiparasitarios/farmacología , Glicopéptidos , Humanos , Péptidos Cíclicos
8.
J Ind Microbiol Biotechnol ; 47(9-10): 845-862, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32623653

RESUMEN

Yarrowia lipolytica is an oleaginous yeast that has been substantially engineered for production of oleochemicals and drop-in transportation fuels. The unique acetyl-CoA/malonyl-CoA supply mode along with the versatile carbon-utilization pathways makes this yeast a superior host to upgrade low-value carbons into high-value secondary metabolites and fatty acid-based chemicals. The expanded synthetic biology toolkits enabled us to explore a large portfolio of specialized metabolism beyond fatty acids and lipid-based chemicals. In this review, we will summarize the recent advances in genetic, omics, and computational tool development that enables us to streamline the genetic or genomic modification for Y. lipolytica. We will also summarize various metabolic engineering strategies to harness the endogenous acetyl-CoA/malonyl-CoA/HMG-CoA pathway for production of complex oleochemicals, polyols, terpenes, polyketides, and commodity chemicals. We envision that Y. lipolytica will be an excellent microbial chassis to expand nature's biosynthetic capacity to produce plant secondary metabolites, industrially relevant oleochemicals, agrochemicals, commodity, and specialty chemicals and empower us to build a sustainable biorefinery platform that contributes to the prosperity of a bio-based economy in the future.


Asunto(s)
Ingeniería Metabólica , Biología Sintética , Biología de Sistemas , Yarrowia , Acetilcoenzima A/metabolismo , Acilcoenzima A , Ácidos Grasos/metabolismo , Lípidos , Malonil Coenzima A/metabolismo , Policétidos/metabolismo , Terpenos/metabolismo , Yarrowia/metabolismo
9.
Small ; 13(34)2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28692763

RESUMEN

Macroscopic porous graphene materials composed of graphene sheets have demonstrated their advantageous aspects in diverse application areas. It is essential to maximize their excellent performances by rationally controlling the sheet arrangement and pore structure. Bulk porous graphene materials with oriented pore structure and arrangement of graphene sheets are prepared by marrying electrolyte-assisted self-assembly and shear-force-induced alignment of graphene oxide sheets, and the super elasticity and anisotropic mechanical, electrical, and thermal properties induced by this unique structure are systematically investigated. Its application in pressure sensing exhibits ultrahigh sensitivity of 313.23 kPa-1 for detecting ultralow pressure variation below 0.5 kPa, and it shows high retention rate for continuously intercepting dye molecules with a high flux of ≈18.7 L m-2 h-1 bar-1 and a dynamic removal rate of 510 mg m-2 h-1 .

10.
Anticancer Drugs ; 26(8): 902-6, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26146864

RESUMEN

The prognosis of postoperatively recurred malignant schwannoma is poor and there is no effective treatment. We had a patient who was found to have a large intrathoracic tumor 1 year after surgery and could not tolerate an operation for the second time. We then decided to evaluate the synergistic effect of recombinant adenovirus-p53 (rAd-p53) combined with radiotherapy for the patient. rAd-p53 was injected intratumorally twice a week before radiotherapy, a total of 10 times, over a course of treatment. Radiotherapy then followed gene therapy at five fractions a week for 5 weeks, with a total dosage of 80.6 Gy/31f in the center part of the tumor and 62 Gy/31f in other locations. The pathological diagnosis of malignant schwannoma indicated that the p53 expression was strongly positive and vascular endothelial growth factor and Bcl-2 were positive before treatment on protein immunohistochemical staining. After treatment, the diameter of the tumor was noticeably reduced and the center part of the tumor presented as a fluid anechoic area and cavities on computed tomographic scanning. The result of the puncture biopsy showed that there were many fibronecrotic tissues and no significant tumor cells. The p53 expression was weakly positive, Vascular endothelial growth factor was negative, and Bcl-2 was weakly positive after treatment on protein immunohistochemical staining.


Asunto(s)
Adenoviridae/genética , Neurilemoma/terapia , Proteína p53 Supresora de Tumor/genética , Anciano , Terapia Combinada , Femenino , Terapia Genética , Humanos , Inyecciones Intralesiones , Neurilemoma/patología , Neurilemoma/radioterapia , Proteína p53 Supresora de Tumor/metabolismo
11.
J Eukaryot Microbiol ; 62(1): 21-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25040451

RESUMEN

Enterocytozoon bieneusi, the most frequently diagnosed microsporidian species in humans, is also identified in a wide range of animals. To date, few data are available on E. bieneusi in yaks (Bos grunniens). In this study, we examined the occurrence and genotype identity of E. bieneusi in yaks in four counties in Qinghai Province of China. Of 327 fecal specimens examined by nested PCR analysis of the ribosomal internal transcribed spacer, 23 (7.0%) were E. bieneusi-positive. DNA sequence analysis of the PCR products revealed the presence of five distinct genotypes: three Group 2 genotypes previously reported in cattle as well as humans (BEB4, I and J) and two novel genotypes (CHN11 and CHN12) belonging to the large zoonotic group (Group 1). Data of the study suggest that these animals could be potential reservoirs for human E. bieneusi infection.


Asunto(s)
Enfermedades de los Bovinos/epidemiología , ADN Espaciador Ribosómico/genética , Enterocytozoon/genética , Genotipo , Microsporidiosis/veterinaria , Filogenia , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , China/epidemiología , Reservorios de Enfermedades/microbiología , Enterocytozoon/clasificación , Enterocytozoon/aislamiento & purificación , Heces/microbiología , Humanos , Microsporidiosis/epidemiología , Microsporidiosis/microbiología , Filogeografía , Reacción en Cadena de la Polimerasa/veterinaria
12.
Parasitol Res ; 114(5): 1811-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25673080

RESUMEN

Cyclospora spp. in nonhuman primates are most closely related to Cyclospora cayetanensis, an emerging human pathogen causing outbreaks of cyclosporiasis in North America. Studies thus far indicate the possible existence of host specificity in Cyclospora spp. In this study, 411 fecal specimens from free-range rhesus monkeys (Macaca mulatta) were collected and examined for Cyclospora by sequence analysis of the small subunit rRNA gene. A novel Cyclospora species was identified in 28 (6.8%) specimens and named Cyclospora macacae based on morphologic and molecular characterizations. The oocyst of C. macacae is spherical and measures 8.49 ± 0.55 × 8.49 ± 0.49 µm in diameter. Phylogenetic analysis grouped this species together with the other four Cyclospora species infecting primates, including C. cayetanensis in humans, forming a monophyletic group closely related to avian Eimeria species. In addition, C. cayetanensis was detected in one specimen, although whether rhesus monkeys can serve as a natural reservoir host of C. cayetanensis needs further investigation.


Asunto(s)
Cyclospora/aislamiento & purificación , Ciclosporiasis/veterinaria , Macaca mulatta , Enfermedades de los Monos/parasitología , Animales , China/epidemiología , Ciclosporiasis/epidemiología , Ciclosporiasis/parasitología , Heces/parasitología , Humanos , Enfermedades de los Monos/epidemiología , América del Norte , Filogenia , Reacción en Cadena de la Polimerasa
13.
Int J Oncol ; 65(2)2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38874004

RESUMEN

Subsequently to the publication of the above article, an interested reader drew to the authors' attention that certain of the EdU assay data shown in Fig. 7E on p. 2418 had already appeared in different form in a previously published paper written by different authors at different research institutes. Owing to the fact that the contentious data in the above article had already been published prior to its submission to International Journal of Oncology, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused.  [International Journal of Oncology 53: 2409­2422, 2018; DOI: 10.3892/ijo.2018.4586].

14.
J Biotechnol ; 382: 37-43, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38244699

RESUMEN

Keratinase, a vital enzyme in hair degradation, requires enhanced stability for industrial applications in the harsh reaction environment used for keratin hydrolysis. Previous studies have focused on improving keratinase thermostability. In this study, directed evolution was applied to enhance the organic solvent stability of the keratinase BLk from Bacillus licheniformis. Three mutants were identified, exhibiting significant enhanced stability in various solvents, although no similar improvements were observed in terms of thermostability. The identified mutations were located on the enzyme surface. The half-lives of the D41A, A24E, and A24Q mutants increased by 47-, 63-, and 61-fold, respectively, in the presence of 50% (v/v) acetonitrile compared to that of the wild type (WT). Similarly, in the presence of 50% (v/v) acetone, the half-lives of these mutants increased by 22-, 27-, and 27-fold compared to that of the WT enzyme. Notably, the proteolytic activity of all the selected mutants was similar to that of the WT enzyme. Furthermore, molecular dynamics simulation was used to assess the possible reasons for enhanced solvent stability. These results suggest that heightened intramolecular interactions, such as hydrogen bonding and hydrophobic interactions, contribute to improved solvent tolerance. The mutants obtained in this study hold significant potential for industrial applications.


Asunto(s)
Péptido Hidrolasas , Solventes/química , Péptido Hidrolasas/metabolismo , Mutación , Hidrólisis , Estabilidad de Enzimas , Temperatura
15.
J Control Release ; 370: 501-515, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38703950

RESUMEN

Although nanomaterial-based nanomedicine provides many powerful tools to treat cancer, most focus on the "immunosilent" apoptosis process. In contrast, ferroptosis and immunogenic cell death, two non-apoptotic forms of programmed cell death (PCD), have been shown to enhance or alter the activity of the immune system. Therefore, there is a need to design and develop nanoplatforms that can induce multiple modes of cell death other than apoptosis to stimulate antitumor immunity and remodel the immunosuppressive tumor microenvironment for cancer therapy. In this study, a new type of multifunctional nanocomposite mainly consisting of HMME, Fe3+ and Tannic acid, denoted HFT NPs, was designed and synthesized to induce multiple modes of cell death and prime the tumor microenvironment (TME). The HFT NPs consolidate two functions into one nano-system: HMME as a sonosensitizer for the generation of reactive oxygen species (ROS) 1O2 upon ultrasound irradiation, and Fe3+ as a GSH scavenger for the induction of ferroptosis and the production of ROS ·OH through inorganic catalytic reactions. The administration of HFT NPs and subsequent ultrasound treatment caused cell death through the consumption of GSH, the generation of ROS, ultimately inducing apoptosis, ferroptosis, and immunogenic cell death (ICD). More importantly, the combination of HFT NPs and ultrasound irradiation could reshape the TME and recruit more T cell infiltration, and its combination with immune checkpoint blockade anti-PD-1 antibody could eradicate tumors with low immunogenicity and a cold TME. This new nano-system integrates sonodynamic and chemodynamic properties to achieve outstanding therapeutic outcomes when combined with immunotherapy. Collectively, this study demonstrates that it is possible to potentiate cancer immunotherapy through the rational and innovative design of relatively simple materials.


Asunto(s)
Ferroptosis , Inmunoterapia , Especies Reactivas de Oxígeno , Microambiente Tumoral , Microambiente Tumoral/efectos de los fármacos , Animales , Inmunoterapia/métodos , Especies Reactivas de Oxígeno/metabolismo , Línea Celular Tumoral , Ferroptosis/efectos de los fármacos , Humanos , Muerte Celular/efectos de los fármacos , Apoptosis/efectos de los fármacos , Ratones Endogámicos C57BL , Taninos/química , Taninos/farmacología , Ratones , Femenino , Nanocompuestos/química , Nanocompuestos/administración & dosificación , Ondas Ultrasónicas , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/patología , Muerte Celular Inmunogénica/efectos de los fármacos
16.
J Immunother Cancer ; 12(7)2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38964787

RESUMEN

BACKGROUND: Chimeric antigen receptor natural killer (CAR-NK) therapy holds great promise for treating hematologic tumors, but its efficacy in solid tumors is limited owing to the lack of suitable targets and poor infiltration of engineered NK cells. Here, we explore whether immunogenic cell death (ICD) marker ERp57 translocated from endoplasmic reticulum to cell surface after drug treatment could be used as a target for CAR-NK therapy. METHODS: To target ERp57, a VHH phage display library was used for screening ERp57-targeted nanobodies (Nbs). A candidate Nb with high binding affinity to both human and mouse ERp57 was used for constructing CAR-NK cells. Various in vitro and in vivo studies were performed to assess the antitumor efficacy of the constructed CAR-NK cells. RESULTS: We demonstrate that the translocation of ERp57 can not only be induced by low-dose oxaliplatin (OXP) treatment but also is spontaneously expressed on the surface of various types of tumor cell lines. Our results show that G6-CAR-NK92 cells can effectively kill various tumor cell lines in vitro on which ERp57 is induced or intrinsically expressed, and also exhibit potent antitumor effects in cancer cell-derived xenograft and patient-derived xenograft mouse models. Additionally, the antitumor activity of G6-CAR-NK92 cells is synergistically enhanced by the low-dose ICD-inducible drug OXP. CONCLUSION: Collectively, our findings suggest that ERp57 can be leveraged as a new tumor antigen for CAR-NK targeting, and the resultant CAR-NK cells have the potential to be applied as a broad-spectrum immune cell therapy for various cancers by combining with ICD inducer drugs.


Asunto(s)
Muerte Celular Inmunogénica , Células Asesinas Naturales , Oxaliplatino , Proteína Disulfuro Isomerasas , Humanos , Animales , Ratones , Oxaliplatino/farmacología , Oxaliplatino/uso terapéutico , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/efectos de los fármacos , Muerte Celular Inmunogénica/efectos de los fármacos , Proteína Disulfuro Isomerasas/metabolismo , Inmunoterapia Adoptiva/métodos , Receptores Quiméricos de Antígenos/inmunología , Receptores Quiméricos de Antígenos/metabolismo , Línea Celular Tumoral , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto , Neoplasias/inmunología , Neoplasias/tratamiento farmacológico , Neoplasias/terapia , Femenino
17.
Adv Sci (Weinh) ; : e2401905, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38888519

RESUMEN

Bacteria can be utilized for cancer therapy owing to their preferential colonization at tumor sites. However, unmodified non-pathogenic bacteria carry potential risks due to their non-specific targeting effects, and their anti-tumor activity is limited when used as monotherapy. In this study, a biohybrid-engineered bacterial system comprising non-pathogenic MG1655 bacteria modified with CDH17 nanobodies on their surface and conjugated with photosensitizer croconium (CR) molecules is developed. The resultant biohybrid bacteria can efficiently home to CDH17-positive tumors, including gastric, pancreatic, and colorectal cancers, and significantly suppress tumor growth upon irradiation. More importantly, biohybrid bacteria-mediated photothermal therapy (PTT) induced abundant macrophage infiltration in a syngeneic murine colorectal model. Further, that the STING pathway is activated in tumor macrophages by the released bacterial nucleic acid after PTT is revealed, leading to the production of type I interferons. The addition of CD47 nanobody but not PD-1 antibody to the PTT regimen can eradicate the tumors and extend survival. This results indicate that bacteria endowed with tumor-specific selectivity and coupled with photothermal payloads can serve as an innovative strategy for low-immunogenicity cancers. This strategy can potentially reprogram the tumor microenvironment by inducing macrophage infiltration and enhancing the efficacy of immunotherapy targeting macrophages.

18.
Biomater Res ; 28: 0041, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38911825

RESUMEN

Surgery and targeted therapy are of equal importance for colorectal cancer (CRC) treatment. However, complete CRC tumor resection remains challenging, and new targeted agents are also needed for efficient CRC treatment. Cadherin 17 (CDH17) is a membrane protein that is highly expressed in CRC and, therefore, is an ideal target for imaging-guided surgery and therapeutics. This study utilizes CDH17 nanobody (E8-Nb) with the near-infrared (NIR) fluorescent dye IRDye800CW to construct a NIR-II fluorescent probe, E8-Nb-IR800CW, and a Pseudomonas exotoxin (PE)-based immunotoxin, E8-Nb-PE38, to evaluate their performance for CRC imaging, imaging-guided precise tumor excision, and antitumor effects. Our results show that E8-Nb-IR800CW efficiently recognizes CDH17 in CRC cells and tumor tissues, produces high-quality NIR-II images for CRC tumors, and enables precise tumor removal guided by NIR-II imaging. Additionally, fluorescent imaging confirms the targeting ability and specificity of the immunotoxin toward CDH17-positive tumors, providing the direct visible evidence for immunotoxin therapy. E8-Nb-PE38 immunotoxin markedly delays the growth of CRC through the induction of apoptosis and immunogenic cell death (ICD) in multiple CRC tumor models. Furthermore, E8-Nb-PE38 combined with 5-FU exerts synergistically antitumor effects and extends survival. This study highlights CDH17 as a promising target for CRC imaging, imaging-guided surgery, and drug delivery. Nanobodies targeting CDH17 hold great potential to construct NIR-II fluorescent probes for surgery navigation, and PE-based toxins fused with CDH17 nanobodies represent a novel therapeutic strategy for CRC treatment. Further investigation is warranted to validate these findings for potential clinical translation.

19.
Appl Microbiol Biotechnol ; 97(11): 4897-906, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22987200

RESUMEN

The present work created an esterase variant from Rhodobacter sphaeroides (RspE) with enhanced selectivity in hydrolytic kinetic resolutions by directed evolution. A "model" substrate, methyl mandelate, was introduced in the high-throughput screening procedure. E values of a variant CH (Asn62Cys/Leu145His) for six different esters were 10-83, which were a relative improvement compared to 2-20 for the wild type. Our subsequent crystal structure interpretation and molecular dynamics simulations helped shed light on the source of enantioselectivity modified by directed evolution. Though mutations displayed no "direct" interaction with the substrate, they were hypothesized to strengthen the intramolecular interaction in the catalytic cavity of variant. Conformation analysis revealed that the enhanced enantioselectivity of variant CH for the seven substrates applied in this study was derived from the decrease in size of the substrate binding pocket.


Asunto(s)
Hidrolasas de Éster Carboxílico/genética , Hidrolasas de Éster Carboxílico/metabolismo , Evolución Molecular Dirigida/métodos , Rhodobacter sphaeroides/enzimología , Rhodobacter sphaeroides/genética , Sustitución de Aminoácidos , Sitios de Unión , Cristalografía por Rayos X , Ácidos Mandélicos/metabolismo , Modelos Moleculares , Simulación de Dinámica Molecular , Mutación Missense , Unión Proteica , Conformación Proteica , Especificidad por Sustrato
20.
Front Bioeng Biotechnol ; 11: 1098116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36714010

RESUMEN

Introduction: Systematic gene knockout studies may offer us novel insights on cell metabolism and physiology. Specifically, the lipid accumulation mechanism at the molecular or cellular level is yet to be determined in the oleaginous yeast Y. lipolytica. Methods: Herein, we established ten engineered strains with the knockout of important genes involving in central carbon metabolism, NADPH generation, and fatty acid biosynthetic pathways. Results: Our result showed that NADPH sources for lipogenesis include the OxPP pathway, POM cycle, and a trans-mitochondrial isocitrate-α-oxoglutarate NADPH shuttle in Y. lipolytica. Moreover, we found that knockout of mitochondrial NAD+ isocitrate dehydrogenase IDH2 and overexpression of cytosolic NADP+ isocitrate dehydrogenase IDP2 could facilitate lipid synthesis. Besides, we also demonstrated that acetate is a more favorable carbon source for lipid synthesis when glycolysis step is impaired, indicating the evolutionary robustness of Y. lipolytica. Discussion: This systematic investigation of gene deletions and overexpression across various lipogenic pathways would help us better understand lipogenesis and engineer yeast factories to upgrade the lipid biomanufacturing platform.

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