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1.
PLoS Pathog ; 18(11): e1010924, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36383559

RESUMEN

Malaria during pregnancy is a major global health problem caused by infection with Plasmodium falciparum parasites. Severe effects arise from the accumulation of infected erythrocytes in the placenta. Here, erythrocytes infected by late blood-stage parasites adhere to placental chondroitin sulphate A (CS) via VAR2CSA-type P. falciparum erythrocyte membrane protein 1 (PfEMP1) adhesion proteins. Immunity to placental malaria is acquired through exposure and mediated through antibodies to VAR2CSA. Through evolution, the VAR2CSA proteins have diversified in sequence to escape immune recognition but retained their overall macromolecular structure to maintain CS binding affinity. This structural conservation may also have allowed development of broadly reactive antibodies to VAR2CSA in immune women. Here we show the negative stain and cryo-EM structure of the only known broadly reactive human monoclonal antibody, PAM1.4, in complex with VAR2CSA. The data shows how PAM1.4's broad VAR2CSA reactivity is achieved through interactions with multiple conserved residues of different sub-domains forming conformational epitope distant from the CS binding site on the VAR2CSA core structure. Thus, while PAM1.4 may represent a class of antibodies mediating placental malaria immunity by inducing phagocytosis or NK cell-mediated cytotoxicity, it is likely that broadly CS binding-inhibitory antibodies target other epitopes at the CS binding site. Insights on both types of broadly reactive monoclonal antibodies may aid the development of a vaccine against placental malaria.


Asunto(s)
Malaria Falciparum , Malaria , Humanos , Femenino , Embarazo , Antígenos de Protozoos , Malaria Falciparum/parasitología , Epítopos , Anticuerpos Antiprotozoarios , Anticuerpos Monoclonales , Microscopía por Crioelectrón , Placenta/metabolismo , Plasmodium falciparum/metabolismo , Eritrocitos/parasitología , Sulfatos de Condroitina/metabolismo
2.
J Biol Chem ; 297(6): 101391, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34762909

RESUMEN

Placental malaria infection is mediated by the binding of the malarial VAR2CSA protein to the placental glycosaminoglycan, chondroitin sulfate. Recombinant subfragments of VAR2CSA (rVAR2) have also been shown to bind specifically and with high affinity to cancer cells and tissues, suggesting the presence of a shared type of oncofetal chondroitin sulfate (ofCS) in the placenta and in tumors. However, the exact structure of ofCS and what determines the selective tropism of VAR2CSA remains poorly understood. In this study, ofCS was purified by affinity chromatography using rVAR2 and subjected to detailed structural analysis. We found high levels of N-acetylgalactosamine 4-O-sulfation (∼80-85%) in placenta- and tumor-derived ofCS. This level of 4-O-sulfation was also found in other tissues that do not support parasite sequestration, suggesting that VAR2CSA tropism is not exclusively determined by placenta- and tumor-specific sulfation. Here, we show that both placenta and tumors contain significantly more chondroitin sulfate moieties of higher molecular weight than other tissues. In line with this, CHPF and CHPF2, which encode proteins required for chondroitin polymerization, are significantly upregulated in most cancer types. CRISPR/Cas9 targeting of CHPF and CHPF2 in tumor cells reduced the average molecular weight of cell-surface chondroitin sulfate and resulted in a marked reduction of rVAR2 binding. Finally, utilizing a cell-based glycocalyx model, we showed that rVAR2 binding correlates with the length of the chondroitin sulfate chains in the cellular glycocalyx. These data demonstrate that the total amount and cellular accessibility of chondroitin sulfate chains impact rVAR2 binding and thus malaria infection.


Asunto(s)
Antígenos de Protozoos/metabolismo , Sulfatos de Condroitina/metabolismo , Glicocálix/metabolismo , Malaria Falciparum/metabolismo , Plasmodium falciparum/metabolismo , Proteínas Protozoarias/metabolismo , Antígenos de Protozoos/química , Antígenos de Protozoos/genética , Sulfatos de Condroitina/química , Sulfatos de Condroitina/genética , Femenino , Glicocálix/química , Glicocálix/genética , Células HEK293 , Células HeLa , Humanos , Malaria Falciparum/genética , N-Acetilgalactosaminiltransferasas/genética , N-Acetilgalactosaminiltransferasas/metabolismo , Placenta/metabolismo , Plasmodium falciparum/genética , Embarazo , Proteínas Protozoarias/química , Proteínas Protozoarias/genética
3.
J Biol Chem ; 295(27): 9134-9146, 2020 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-32398257

RESUMEN

Findings from recent studies have indicated that enzymes containing more than one catalytic domain may be particularly powerful in the degradation of recalcitrant polysaccharides such as chitin and cellulose. Some known multicatalytic enzymes contain several glycoside hydrolase domains and one or more carbohydrate-binding modules (CBMs). Here, using bioinformatics and biochemical analyses, we identified an enzyme, Jd1381 from the actinobacterium Jonesia denitrificans, that uniquely combines two different polysaccharide-degrading activities. We found that Jd1381 contains an N-terminal family AA10 lytic polysaccharide monooxygenase (LPMO), a family 5 chitin-binding domain (CBM5), and a family 18 chitinase (Chi18) domain. The full-length enzyme, which seems to be the only chitinase produced by J. denitrificans, degraded both α- and ß-chitin. Both the chitinase and the LPMO activities of Jd1381 were similar to those of other individual chitinases and LPMOs, and the overall efficiency of chitin degradation by full-length Jd1381 depended on its chitinase and LPMO activities. Of note, the chitin-degrading activity of Jd1381 was comparable with or exceeded the activities of combinations of well-known chitinases and an LPMO from Serratia marcescens Importantly, comparison of the chitinolytic efficiency of Jd1381 with the efficiencies of combinations of truncated variants-JdLPMO10 and JdCBM5-Chi18 or JdLPMO10-CBM5 and JdChi18-indicated that optimal Jd1381 activity requires close spatial proximity of the LPMO10 and the Chi18 domains. The demonstration of intramolecular synergy between LPMOs and hydrolytic enzymes reported here opens new avenues toward the development of efficient catalysts for biomass conversion.


Asunto(s)
Actinobacteria/enzimología , Quitinasas/metabolismo , Actinobacteria/metabolismo , Proteínas Bacterianas/metabolismo , Catálisis , Celulosa/metabolismo , Quitina/metabolismo , Glicósido Hidrolasas/metabolismo , Glicósidos/metabolismo , Hidrólisis , Oxigenasas de Función Mixta/metabolismo , Oxidación-Reducción , Estrés Oxidativo/fisiología , Polisacáridos/metabolismo , Especificidad por Sustrato
4.
Glycobiology ; 30(12): 989-1002, 2020 12 09.
Artículo en Inglés | MEDLINE | ID: mdl-32337544

RESUMEN

Chondroitin sulfate (CS) is the placental receptor for the VAR2CSA malaria protein, expressed at the surface of infected erythrocytes during Plasmodium falciparum infection. Infected cells adhere to syncytiotrophoblasts or get trapped within the intervillous space by binding to a determinant in a 4-O-sulfated CS chains. However, the exact structure of these glycan sequences remains unclear. VAR2CSA-reactive CS is also expressed by tumor cells, making it an attractive target for cancer diagnosis and therapeutics. The identities of the proteoglycans carrying these modifications in placental and cancer tissues remain poorly characterized. This information is clinically relevant since presentation of the glycan chains may be mediated by novel core proteins or by a limited subset of established proteoglycans. To address this question, VAR2CSA-binding proteoglycans were affinity-purified from the human placenta, tumor tissues and cancer cells and analyzed through a specialized glycoproteomics workflow. We show that VAR2CSA-reactive CS chains associate with a heterogenous group of proteoglycans, including novel core proteins. Additionally, this work demonstrates how affinity purification in combination with glycoproteomics analysis can facilitate the characterization of CSPGs with distinct CS epitopes. A similar workflow can be applied to investigate the interaction of CSPGs with other CS binding lectins as well.


Asunto(s)
Antígenos de Protozoos/metabolismo , Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Placenta/metabolismo , Proteómica , Neoplasias de la Vejiga Urinaria/metabolismo , Antígenos de Protozoos/química , Proteoglicanos Tipo Condroitín Sulfato/química , Cromatografía de Afinidad , Femenino , Humanos , Placenta/química , Embarazo , Neoplasias de la Vejiga Urinaria/patología
5.
Int J Mol Sci ; 21(7)2020 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-32244341

RESUMEN

Early detection and monitoring of cancer progression is key to successful treatment. Therefore, much research is invested in developing technologies, enabling effective and valuable use of non-invasive liquid biopsies. This includes the detection and analysis of circulating tumor cells (CTCs) from blood samples. Recombinant malaria protein VAR2CSA (rVAR2) binds a unique chondroitin sulfate modification present on the vast majority of cancers and thereby holds promise as a near-universal tumor cell-targeting reagent to isolate CTCs from complex blood samples. This study describes a technical approach for optimizing the coupling of rVAR2 to magnetic beads and the development of a CTC isolation platform targeting a range of different cancer cell lines. We investigate both direct and indirect approaches for rVAR2-mediated bead retrieval of cancer cells and conclude that an indirect capture approach is most effective for rVAR2-based cancer cell retrieval.


Asunto(s)
Antígenos de Protozoos/genética , Detección Precoz del Cáncer/métodos , Células Neoplásicas Circulantes/patología , Línea Celular Tumoral , Sulfatos de Condroitina/metabolismo , Humanos , Magnetismo , Proteínas Recombinantes
6.
Appl Microbiol Biotechnol ; 100(1): 263-77, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26428235

RESUMEN

Autocrine activation of c-kit (KIT receptor tyrosine kinase) has been postulated to be a potent oncogenic driver in small cell lung cancer, neuroblastoma (NB), and poorly differentiated colorectal carcinoma (CRC). Although targeted therapy involving tyrosine kinase inhibitors (TKIs) such as imatinib mesylate is highly effective for gastrointestinal stromal tumor carrying V560G c-kit mutation, it does not show much potential for targeting wild-type KIT (WT-KIT). Our study demonstrates the role of stem cell factor (SCF)-based toxin conjugates for targeting WT-KIT-overexpressing malignancies such as NBs and CRCs. We constructed SCF-based recombinant bacterial toxins by genetically fusing mutated form of natural ligand SCF to receptor binding deficient forms of Diphtheria toxin (DT) or Pseudomonas exotoxin A (ETA') and evaluated their efficacy in vitro. Efficient targeting was achieved in all receptor-positive neuroblastoma (IMR-32 and SHSY5Y) and colon cancer cell lines (COLO 320DM, HCT 116, and DLD-1) but not in receptor-negative breast carcinoma cell line (MCF-7) thereby proving specificity. While dose- and time-dependent cytotoxicity was observed in both neuroblastoma cell lines, COLO 320DM and HCT 116 cells, only an anti-proliferative effect was observed in DLD-1 cells. We prove that these novel targeting agents have promising potential as KIT receptor tyrosine kinase targeting system.


Asunto(s)
Antineoplásicos/metabolismo , Toxinas Bacterianas/metabolismo , Neoplasias Colorrectales , Sistemas de Liberación de Medicamentos/métodos , Neuroblastoma , Proteínas Proto-Oncogénicas c-kit/antagonistas & inhibidores , Factor de Células Madre/metabolismo , Toxinas Bacterianas/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Factor de Células Madre/genética
7.
Nature ; 459(7244): 274-7, 2009 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-19444217

RESUMEN

RNA interference pathways use small RNAs to mediate gene silencing in eukaryotes. In addition to small interfering RNAs (siRNAs) and microRNAs, several types of endogenously produced small RNAs have important roles in gene regulation, germ cell maintenance and transposon silencing. The production of some of these RNAs requires the synthesis of aberrant RNAs (aRNAs) or pre-siRNAs, which are specifically recognized by RNA-dependent RNA polymerases to make double-stranded RNA. The mechanism for aRNA synthesis and recognition is largely unknown. Here we show that DNA damage induces the expression of the Argonaute protein QDE-2 and a new class of small RNAs in the filamentous fungus Neurospora crassa. This class of small RNAs, known as qiRNAs because of their interaction with QDE-2, are about 20-21 nucleotides long (several nucleotides shorter than Neurospora siRNAs), with a strong preference for uridine at the 5' end, and originate mostly from the ribosomal DNA locus. The production of qiRNAs requires the RNA-dependent RNA polymerase QDE-1, the Werner and Bloom RecQ DNA helicase homologue QDE-3 and dicers. qiRNA biogenesis also requires DNA-damage-induced aRNAs as precursors, a process that is dependent on both QDE-1 and QDE-3. Notably, our results suggest that QDE-1 is the DNA-dependent RNA polymerase that produces aRNAs. Furthermore, the Neurospora RNA interference mutants show increased sensitivity to DNA damage, suggesting a role for qiRNAs in the DNA-damage response by inhibiting protein translation.


Asunto(s)
Daño del ADN/genética , Regulación Fúngica de la Expresión Génica , Neurospora crassa/genética , ARN de Hongos/biosíntesis , ARN de Hongos/genética , ARN Interferente Pequeño/biosíntesis , ARN Interferente Pequeño/genética , ADN Helicasas/genética , ADN Helicasas/metabolismo , ADN Ribosómico/genética , ADN de Cadena Simple , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Datos de Secuencia Molecular , Neurospora crassa/enzimología , Biosíntesis de Proteínas , ARN de Hongos/metabolismo , ARN Interferente Pequeño/metabolismo , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Moldes Genéticos
8.
EMBO Mol Med ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39406935

RESUMEN

Glycosaminoglycans are often deprioritized as targets for synthetic immunotherapy due to the complexity of glyco-epitopes and limited options for obtaining specific subtype binding. Solid tumors express proteoglycans that are modified with oncofetal chondroitin sulfate (CS), a modification normally restricted to the placenta. Here, we report the design and functionality of transient chimeric antigen receptor (CAR) T cells with selectivity to oncofetal CS. Following expression in T cells, the CAR could be "armed" with recombinant VAR2CSA lectins (rVAR2) to target tumor cells expressing oncofetal CS. While unarmed CAR T cells remained inactive in the presence of target cells, VAR2-armed CAR T cells displayed robust activation and the ability to eliminate diverse tumor cell types in vitro. Cytotoxicity of the CAR T cells was proportional to the concentration of rVAR2 available to the CAR, offering a potential molecular handle to finetune CAR T cell activity. In vivo, armed CAR T cells rapidly targeted bladder tumors and increased the survival of tumor-bearing mice. Thus, our work indicates that cancer-restricted glycosaminoglycans may be exploited as potential targets for CAR T cell therapy.

9.
Nat Commun ; 15(1): 7553, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39215044

RESUMEN

Molecular similarities between embryonic and malignant cells can be exploited to target tumors through specific signatures absent in healthy adult tissues. One such embryonic signature tumors express is oncofetal chondroitin sulfate (ofCS), which supports disease progression and dissemination in cancer. Here, we report the identification and characterization of phage display-derived antibody fragments recognizing two distinct ofCS epitopes. These antibody fragments show binding affinity to ofCS in the low nanomolar range across a broad selection of solid tumor types in vitro and in vivo with minimal binding to normal, inflamed, or benign tumor tissues. Anti-ofCS antibody drug conjugates and bispecific immune cell engagers based on these targeting moieties disrupt tumor progression in animal models of human and murine cancers. Thus, anti-ofCS antibody fragments hold promise for the development of broadly effective therapeutic and diagnostic applications targeting human malignancies.


Asunto(s)
Sulfatos de Condroitina , Neoplasias , Animales , Humanos , Sulfatos de Condroitina/metabolismo , Sulfatos de Condroitina/inmunología , Ratones , Neoplasias/inmunología , Neoplasias/terapia , Línea Celular Tumoral , Femenino , Epítopos/inmunología , Antígenos de Neoplasias/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto , Inmunoconjugados/uso terapéutico , Biblioteca de Péptidos
10.
Chembiochem ; 14(18): 2480-91, 2013 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-24166732

RESUMEN

The Basidiomycota fungi represent a diverse source of natural products, particularly the sesquiterpenoids. Recently, genome sequencing, genome mining, and the subsequent discovery of a suite of sesquiterpene synthases in Omphalotus olearius was described. A predictive framework was developed to facilitate the discovery of sesquiterpene synthases in Basidiomycota. Phylogenetic analyses indicated a conservation of both sequence and initial cyclization mechanisms used. Here, the first robust application of this predictive framework is reported. It was used to selectively identify sesquiterpene synthases that follow 1,6-, 1,10-, and 1,11-cyclization mechanisms in the crust fungus Stereum hirsutum. The successful identification and characterization of a 1,6- and a 1,10-cyclizing sesquiterpene synthase, as well as three 1,11-cyclizing Δ(6) -protoilludene synthases, is described. This study verifies the accuracy and utility of the predictive framework as a roadmap for the discovery of specific sesquiterpene synthases from Basidiomycota, and thus represents an important step forward in natural product discovery.


Asunto(s)
Basidiomycota/enzimología , Productos Biológicos/metabolismo , Biología Computacional/métodos , Ligasas/metabolismo , Sesquiterpenos/metabolismo , Basidiomycota/química , Basidiomycota/genética , Basidiomycota/metabolismo , Productos Biológicos/química , Clonación Molecular , Ligasas/genética , Familia de Multigenes , Filogenia , Sesquiterpenos/química
11.
Ind Psychiatry J ; 32(2): 202-214, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38161465

RESUMEN

Cannabis use has been stated as a causal risk factor for the occurrence of schizophrenia and other psychotic disorders. There is a dearth of literature stating the association of cannabis with bipolar disorder. This review aimed to find the repercussion of cannabis use on the onset of the first episode of bipolar disorder and the worsening of the symptoms in pre-existing illness. A thorough systematic review of the existing literature was carried out using the PRISMA guidelines. PubMed, Medline, EMBASE, SCOPUS, and Google-scholar databases were searched for studies fitting our study's inclusion and exclusion criteria. A total of 25 studies were included in the systematic review and out of these 25 studies, five prospective studies met the inclusion criteria for the primary outcome meta-analysis. A total sample of 13,624 individuals was included in these five studies. A fixed effect model was used in the meta-analysis of these five studies and it revealed an association between cannabis and bipolar disorder with an effect size of 2.63 (95% CI: 1.95-3.53) (heterogeneity: chi² = 3.01, df = 3 (P = 0.39); I² = 0%). Our findings propose that cannabis use may precipitate or worsen bipolar disorder. This highlights the importance of the detrimental effect of cannabis use on bipolar disorder and the need to discourage cannabis use in the youth culture. High-quality prospective studies are required to delineate the effect of cannabis use on bipolar disorder.

12.
Pharmacol Ther ; 251: 108526, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37690483

RESUMEN

The tumor microenvironment is surrounded by blood vessels and consists of malignant, non-malignant, and immune cells, as well as signalling molecules, which primarily affect the therapeutic response and curative effects of drugs in clinical studies. Tumor-infiltrating immune cells participate in tumor progression, impact anticancer therapy, and eventually lead to the development of immune tolerance. Immunotherapy is evolving as a promising therapeutic intervention to stimulate and activate the immune system to suppress cancer cell growth. Endometrial cancer (EC) is an immunogenic disease, and in recent years, immunotherapy has shown benefit in the treatment of recurrent and advanced EC. This review discusses the key molecular pathways associated with the intra-tumoral immune response and the involvement of circulatory signalling molecules. Specific immunologic signatures in EC which offer targets for immunomodulating agents, are also discussed. We have summarized the available literature in support of using immunotherapy in EC. Lastly, we have also discussed ongoing clinical trials that may offer additional promising immunotherapy options in the future. The manuscript also explored innovative approaches for screening and identifying effective drugs, and to reduce the financial burdens for the development of personalized treatment strategies. Collectively, we aim to provide a comprehensive review of the role of immune cells and the tumor microenvironment in the development, progression, and treatment of EC.


Asunto(s)
Neoplasias Endometriales , Microambiente Tumoral , Femenino , Humanos , Neoplasias Endometriales/tratamiento farmacológico , Inmunoterapia
13.
ACS Nano ; 17(14): 13500-13509, 2023 07 25.
Artículo en Inglés | MEDLINE | ID: mdl-37435892

RESUMEN

Malaria infected erythrocytes utilize the parasite protein VAR2CSA to bind to a unique presentation of chondroitin sulfate (CS) for their placenta specific tropism. Interestingly, many cancers express a similar form of CS, thereby termed oncofetal CS (ofCS). The distinctive tropism of malaria infected erythrocytes and the identification of oncofetal CS, therefore, represent potentially potent tools for cancer targeting. Here we describe an intriguing drug delivery platform that effectively mimics infected erythrocytes and their specificity for ofCS. We used a lipid catcher-tag conjugation system for the functionalization of erythrocyte membrane-coated drug carriers with recombinant VAR2CSA (rVAR2). We show that these malaria mimicking erythrocyte nanoparticles (MMENPs) loaded with docetaxel (DTX) specifically target and kill melanoma cells in vitro. We further demonstrate effective targeting and therapeutic efficacy in a xenografted melanoma model. These data thus provide a proof of concept for the use of a malaria biomimetic for tumor targeted drug delivery. Given the broad presentation of ofCS found across various types of malignancies, this biomimetic may therefore show potential as a broadly targeted cancer therapy against multiple tumor indications.


Asunto(s)
Malaria Falciparum , Malaria , Melanoma , Humanos , Antígenos de Protozoos/metabolismo , Biomimética , Sulfatos de Condroitina/metabolismo , Eritrocitos/metabolismo , Malaria Falciparum/metabolismo , Plasmodium falciparum
14.
J Exp Clin Cancer Res ; 42(1): 106, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37118819

RESUMEN

BACKGROUND: The malaria protein VAR2CSA binds oncofetal chondroitin sulfate (ofCS), a unique chondroitin sulfate, expressed on almost all mammalian cancer cells. Previously, we produced a bispecific construct targeting ofCS and human T cells based on VAR2CSA and anti-CD3 (V-aCD3Hu). V-aCD3Hu showed efficacy against xenografted tumors in immunocompromised mice injected with human immune cells at the tumor site. However, the complex effects potentially exerted by the immune system as a result of the treatment cannot occur in mice without an immune system. Here we investigate the efficacy of V-aCD3Mu as a monotherapy and combined with immune checkpoint inhibitors in mice with a fully functional immune system. METHODS: We produced a bispecific construct consisting of a recombinant version of VAR2CSA coupled to an anti-murine CD3 single-chain variable fragment. Flow cytometry and ELISA were used to check cell binding capabilities and the therapeutic effect was evaluated in vitro in a killing assay. The in vivo efficacy of V-aCD3Mu was then investigated in mice with a functional immune system and established or primary syngeneic tumors in the immunologically "cold" 4T1 mammary carcinoma, B16-F10 malignant melanoma, the pancreatic KPC mouse model, and in the immunologically "hot" CT26 colon carcinoma model. RESULTS: V-aCD3Mu had efficacy as a monotherapy, and the combined treatment of V-aCD3Mu and an immune checkpoint inhibitor showed enhanced effects resulting in the complete elimination of solid tumors in the 4T1, B16-F10, and CT26 models. This anti-tumor effect was abscopal and accompanied by a systemic increase in memory and activated cytotoxic and helper T cells. The combined treatment also led to a higher percentage of memory T cells in the tumor without an increase in regulatory T cells. In addition, we observed partial protection against re-challenge in a melanoma model and full protection in a breast cancer model. CONCLUSIONS: Our findings suggest that V-aCD3Mu combined with an immune checkpoint inhibitor renders immunologically "cold" tumors "hot" and results in tumor elimination. Taken together, these data provide proof of concept for the further clinical development of V-aCD3 as a broad cancer therapy in combination with an immune checkpoint inhibitor.


Asunto(s)
Anticuerpos Biespecíficos , Carcinoma , Melanoma Experimental , Humanos , Ratones , Animales , Sulfatos de Condroitina/farmacología , Sulfatos de Condroitina/metabolismo , Memoria Inmunológica , Inhibidores de Puntos de Control Inmunológico , Melanoma Experimental/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Anticuerpos Biespecíficos/farmacología , Anticuerpos Biespecíficos/uso terapéutico , Línea Celular Tumoral , Mamíferos/metabolismo
15.
Int J Clin Pediatr Dent ; 15(2): 143-148, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37457212

RESUMEN

Aims and objectives: The aims and objectives of this study were to evaluate the oral health status in a group of mentally disabled children, to identify the oral health knowledge of parents and to assess the impact of audiovisual oral health education program. Materials and methods: The study sample comprised of 120 mentally disabled subjects aged 5-16 years and 40 parents attending a vocational institute in Jaipur, India. Caries status and oral hygiene status were assessed by DMFT Index and Simplified Oral Hygiene Index (OHI-S) of Greene and Vermillion, respectively. Twenty pre- and post-structured close-ended questions were designed and a 5-minute video on oral health education was prepared. Data was analyzed by using one way ANOVA test followed by Post hoc Tukeys HSD Test, Wilcoxon Signed Rank Test, and Chi-square test. Effectiveness index was calculated to find the impact of AV Teaching Program. Results: Oral hygiene status deteriorates as the severity of mental retardation increases but it was not found significantly associated with oral hygiene status. An effectiveness index of at least 0.5 indicates that the instructional media was satisfactorily effective. Conclusion: Maximum children with poor oral hygiene were in the category of severe mental retardation and mean OHI-S score decreases from severe-to-mild mental retardation. The newly designed audiovisual aid on complete oral health care was effective at some levels in improving the oral health knowledge of the parents/caregivers of mentally retarded children. How to cite this article: Shah RK, Choudhary S, Tandon S. Oral Health Status in Mentally Disabled Children, Dental Care Knowledge of Parents, and the Impact of Audiovisual Oral Health Education Program. Int J Clin Pediatr Dent 2022;15(2):143-148.

16.
J Neurosci Rural Pract ; 13(4): 785-790, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36743762

RESUMEN

Objectives: Delay in institution of appropriate mental healthcare is closely linked with attitudes, stigma, and availability of services, which further directs the help seeking pathways. This study was aimed to assess the pathway of care and attitudes toward psychotropic medications among patients with depressive disorder and psychotic disorders. Materials and Methods: Eighty outpatients with depressive disorder and 40 patients with psychotic disorder were assessed in a tertiary care center for pathways to care and attitude toward psychotropics through Attitude toward Psychotropic Medications Questionnaire and Drug attitude inventory-10. Results: The psychiatrist remained the most common first treatment contact (46% in depression and 62% in psychosis). Greater number of patients in psychotic disorder group had first treatment contact with faith healers or exorcist (17.5%), compared to depressive disorder (6.2%). Patients in depressive group had more favorable attitude toward psychotropics compared to psychosis group. Majority of patients had favorable attitude toward psychotropic medications, but they also had substantial misconceptions about side effects, utility, and need of taking lesser than prescribed doses. Conclusions: Although majority of patients had favorable attitude, they also had substantial misconceptions about medications. These issues need to be addressed for better delivery of comprehensive mental healthcare.

17.
Artículo en Inglés | MEDLINE | ID: mdl-36126919

RESUMEN

Objective: To explore the psychological impact of the coronavirus disease 2019 (COVID-19) pandemic and associated lockdown on patients with psychiatric illness.Methods: An online survey-based cross-sectional study was conducted among patients receiving follow-up treatment at a tertiary care center from January to March 2020. The data were collected using a questionnaire about the possible challenges in 3 broad areas: treatment-related challenges, psychosocial difficulties, and concerns related to COVID-19.Results: The majority of patients (72.6%) reported a positive impact due to the increased availability of family support. Patients with depression and anxiety disorders (39.0%) experienced a more negative impact compared to those with psychotic disorders. Many of the psychiatric patients (22.6%) stopped medications and had difficulties accessing health services. Patients also experienced increased interpersonal conflict, sleep difficulties, and a surge in screen time.Conclusions: The findings highlight the difficulties faced by patients with psychiatric illnesses and emphasize the importance of family cohesion during times of crisis.


Asunto(s)
COVID-19 , Trastornos Mentales , Control de Enfermedades Transmisibles , Estudios Transversales , Humanos , Trastornos Mentales/epidemiología , Trastornos Mentales/psicología , Trastornos Mentales/terapia , Pacientes Ambulatorios , Pandemias
18.
Sci Rep ; 12(1): 3075, 2022 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-35197518

RESUMEN

Proteoglycans are proteins that are modified with glycosaminoglycan chains. Chondroitin sulfate proteoglycans (CSPGs) are currently being exploited as targets for drug-delivery in various cancer indications, however basic knowledge on how CSPGs are internalized in tumor cells is lacking. In this study we took advantage of a recombinant CSPG-binding lectin VAR2CSA (rVAR2) to track internalization and cell fate of CSPGs in tumor cells. We found that rVAR2 is internalized into cancer cells via multiple internalization mechanisms after initial docking on cell surface CSPGs. Regardless of the internalization pathway used, CSPG-bound rVAR2 was trafficked to the early endosomes in an energy-dependent manner but not further transported to the lysosomal compartment. Instead, internalized CSPG-bound rVAR2 proteins were secreted with exosomes to the extracellular environment in a strictly chondroitin sulfate-dependent manner. In summary, our work describes the cell fate of rVAR2 proteins in tumor cells after initial binding to CSPGs, which can be further used to inform development of rVAR2-drug conjugates and other therapeutics targeting CSPGs.


Asunto(s)
Proteoglicanos Tipo Condroitín Sulfato/metabolismo , Lectinas/metabolismo , Neoplasias/metabolismo , Transporte de Proteínas , Línea Celular Tumoral , Membrana Celular/metabolismo , Endosomas/metabolismo , Exosomas/metabolismo , Humanos , Unión Proteica , Proteínas Recombinantes/metabolismo
19.
Nat Commun ; 13(1): 4760, 2022 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-35963852

RESUMEN

Lineage plasticity of prostate cancer is associated with resistance to androgen receptor (AR) pathway inhibition (ARPI) and supported by a reactive tumor microenvironment. Here we show that changes in chondroitin sulfate (CS), a major glycosaminoglycan component of the tumor cell glycocalyx and extracellular matrix, is AR-regulated and promotes the adaptive progression of castration-resistant prostate cancer (CRPC) after ARPI. AR directly represses transcription of the 4-O-sulfotransferase gene CHST11 under basal androgen conditions, maintaining steady-state CS in prostate adenocarcinomas. When AR signaling is inhibited by ARPI or lost during progression to non-AR-driven CRPC as a consequence of lineage plasticity, CHST11 expression is unleashed, leading to elevated 4-O-sulfated chondroitin levels. Inhibition of the tumor cell CS glycocalyx delays CRPC progression, and impairs growth and motility of prostate cancer after ARPI. Thus, a reactive CS glycocalyx supports adaptive survival and treatment resistance after ARPI, representing a therapeutic opportunity in patients with advanced prostate cancer.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Andrógenos , Sulfatos de Condroitina , Glicocálix/metabolismo , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Transducción de Señal , Microambiente Tumoral
20.
Appl Microbiol Biotechnol ; 92(6): 1275-86, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22033566

RESUMEN

The BioBrick™ paradigm for the assembly of enzymatic pathways is being adopted and becoming a standard practice in microbial engineering. We present a strategy to adapt the BioBrick™ paradigm to allow the quick assembly of multi-gene pathways into a number of vectors as well as for the quick mobilization of any cloned gene into vectors with different features for gene expression and protein purification. A primary BioBrick™ (BB-eGFP) was developed where the promoter/RBS, multiple cloning sites, optional protein purification affinity tags and reporter gene were all separated into discrete regions by additional restriction enzymes. This primary BB-eGFP then served as the template for additional BioBrick™ vectors with different origins of replication, antibiotic resistances, inducible promoters (arabinose, IPTG or anhydrotetracycline), N- or C-terminal Histidine tags with thrombin cleavage, a LacZα reporter gene and an additional origin of mobility (oriT). All developed BioBricks™ and BioBrick™ compatible vectors were shown to be functional by measuring reporter gene expression. Lastly, a C(30) carotenoid pathway was assembled as a model enzymatic pathway to demonstrate in vivo functionality and compatibility of this engineered vector system.


Asunto(s)
Bioingeniería/métodos , Escherichia coli/genética , Vectores Genéticos/genética , Redes y Vías Metabólicas , Bioingeniería/instrumentación , Escherichia coli/metabolismo , Vectores Genéticos/metabolismo , Plásmidos/genética , Plásmidos/metabolismo , Regiones Promotoras Genéticas
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