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1.
Traffic ; 22(11): 377-396, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34480404

RESUMO

Phosphorylation of the central adaptor protein complex, AP-2 is pivotal for clathrin-mediated endocytosis (CME). Here, we uncover the role of an uncharacterized kinase (BMP-2 inducible kinase-BMP2K) in AP-2 phosphorylation. We demonstrate that BMP2K can phosphorylate AP-2 in vitro and in vivo. Functional impairment of BMP2K impedes AP-2 phosphorylation leading to defects in clathrin-coated pit (CCP) morphology and cargo internalization. BMP2K engages AP-2 via its extended C-terminus and this interaction is important for its CCP localization and function. Notably, endogenous BMP2K levels decline upon functional impairment of AP-2 indicating AP-2 dependent BMP2K stabilization in cells. Further, functional inactivation of BMP2K in zebrafish embryos yields gastrulation phenotypes which mirror AP-2 loss-of-function suggesting physiological relevance of BMP2K in vertebrates. Together, our findings propose involvement of a novel kinase in AP-2 phosphorylation and in the operation of CME.


Assuntos
Complexo 2 de Proteínas Adaptadoras , Clatrina , Complexo 2 de Proteínas Adaptadoras/metabolismo , Animais , Clatrina/metabolismo , Endocitose/fisiologia , Fosforilação , Peixe-Zebra/metabolismo
2.
FASEB J ; 36(10): e22566, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36165231

RESUMO

CMTM6, a type 3 transmembrane protein, is known to stabilize the expression of programmed cell death ligand 1 (PD-L1) and hence facilitates the immune evasion of tumor cells. Recently, we demonstrated that CMTM6 is a major driver of cisplatin resistance in oral squamous cell carcinomas (OSCC). However, the detailed mechanism of how CMTM6 rewires cisplatin resistance in OSCC is yet to be explored. RNA sequencing analysis of cisplatin-resistant OSCC lines stably expressing Nt shRNA and CMTM6 shRNA revealed that CMTM6 might be a potential regulator of the ribosome biogenesis network. Knocking down CMTM6 significantly inhibited transcription of 47S precursor rRNA and hindered the nucleolar structure, indicating reduced ribosome biogenesis. When CMTM6 was ectopically over-expressed in CMTM6KD cells, almost all ribosomal machinery components were rescued. Mechanistically, CMTM6 induced the expression of C-Myc, which promotes RNA polymerase I mediated rDNA transcription. In addition to this, CMTM6 was also found to regulate the AKT-mTORC1-dependent ribosome biogenesis and protein synthesis in cisplatin-resistant lines. The nude mice and zebrafish xenograft experiments indicate that blocking ribosome synthesis either by genetic inhibitor (CMTM6KD) or pharmacological inhibitor (CX-5461) significantly restores cisplatin-mediated cell death in chemoresistant OSCC. Overall, our study suggests that CMTM6 is a major regulator of the ribosome biogenesis network and targeting the ribosome biogenesis network is a viable target to overcome chemoresistance in OSCC. The novel combination of CX-5461 and cisplatin deserves further clinical investigation in advanced OSCC.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Animais , Antígeno B7-H1 , Carcinoma de Células Escamosas/genética , Morte Celular , Linhagem Celular Tumoral , Cisplatino/farmacologia , DNA Ribossômico , Humanos , Ligantes , Alvo Mecanístico do Complexo 1 de Rapamicina , Camundongos , Camundongos Nus , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Proteínas Proto-Oncogênicas c-akt , RNA Polimerase I , RNA Interferente Pequeno , Ribossomos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Peixe-Zebra/genética
3.
J Immunol ; 207(8): 2129-2142, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34544800

RESUMO

The host immune responses to Staphylococcus epidermidis, a frequent cause of nosocomial infections, are not well understood. We have established a bath immersion model of this infection in zebrafish (Danio rerio) larvae. Macrophages play a primary role in the host immune response and are involved in clearance of infection in the larvae. S. epidermidis infection results in upregulation of tlr-2 There is marked inflammation characterized by heightened NF-κB signaling and elevation of several proinflammatory cytokines. There is rapid upregulation of il-1b and tnf-a transcripts, whereas an increase in il-6 levels is relatively more delayed. The IL-6 signaling pathway is further amplified by elevation of IL-6 signal transducer (il-6st) levels, which negatively correlates with miRNA dre-miR-142a-5p. Enhanced IL-6 signaling is protective to the host in this model as inhibition of the signaling pathway resulted in increased mortality upon S. epidermidis infection. Our study describes the host immune responses to S. epidermidis infection, establishes the importance of IL-6 signaling, and identifies a potential role of miR-142-5p-il-6st interaction in this infection model.


Assuntos
Interleucina-6/metabolismo , NF-kappa B/metabolismo , Infecções Estafilocócicas/imunologia , Staphylococcus epidermidis/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados , Células Cultivadas , Infecção Hospitalar , Modelos Animais de Doenças , Resistência à Doença , Humanos , Larva , MicroRNAs/genética , NF-kappa B/genética , Transdução de Sinais , Receptor 2 Toll-Like/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
4.
Physiol Mol Biol Plants ; 29(8): 1073-1079, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37829700

RESUMO

We remember Dr Ajay Parida, a leading plant biotechnologist, whose premature passing has deprived the Indian plant science community of a committed scientist and an able administrator. Born on 12 December 1963 in Bhagabanpur, Cuttack District (now Jajpur district), Odisha, he passed away in Guwahati on 19 July 2022. A collegial scientist, his down-to-earth and approachable nature, as well as his resourcefulness were instrumental in advancing the cause of Indian science and harnessing frontier biotechnological tools as vehicles of social consciousness. His expertise in quantitative DNA variation and molecular marker analysis, paved the way for subsequent research on mangrove molecular diversity at the M. S. Swaminathan Research Foundation (MSSRF), Chennai. His contributions to mangrove biology, genetics and genomics as well as extremophile plant species in the Indian context over two decades are a benchmark in his field. He also provided commendable leadership in his capacity as Director, Institute of Life Sciences (ILS), Bhubaneshwar during the COVID-19 pandemic.

5.
Lab Invest ; 102(3): 298-311, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34773069

RESUMO

Pancreatic cancer (PC) is highly resistant to chemo and radiotherapy. Radiation-induced fibrosis (RIF) is a major cause of clinical concern for various malignancies, including PC. In this study, we aimed to evaluate the radiosensitizing and anti-RIF potential of fluvastatin in PC. Short-term viability and clonogenic survival assays were used to evaluate the radiosensitizing potential of fluvastatin in multiple human and murine PC cell lines. The expression of different proteins was analyzed to understand the mechanisms of fluvastatin-mediated radiosensitization of PC cells and its anti-RIF effects in both mouse and human pancreatic stellate cells (PSCs). Finally, these effects of fluvastatin and/or radiation were assessed in an immune-competent syngeneic murine model of PC. Fluvastatin radiosensitized multiple PC cell lines, as well as radioresistant cell lines in vitro, by inhibiting radiation-induced DNA damage repair response. Nonmalignant cells, such as PSCs and NIH3T3 cells, were less sensitive to fluvastatin-mediated radiosensitization than PC cells. Interestingly, fluvastatin suppressed radiation and/or TGF-ß-induced activation of PSCs, as well as the fibrogenic properties of these cells in vitro. Fluvastatin considerably augmented the antitumor effect of external radiation therapy and also suppressed intra-tumor RIF in vivo. These findings suggested that along with radiation, fluvastatin co-treatment may be a potential therapeutic approach against PC.


Assuntos
Fluvastatina/farmacologia , Neoplasias Pancreáticas/patologia , Tolerância a Radiação/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Autofagia/efeitos dos fármacos , Autofagia/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/embriologia , Embrião não Mamífero/efeitos da radiação , Fibrose/prevenção & controle , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Células NIH 3T3 , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/patologia , Neoplasias Experimentais/radioterapia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Peixe-Zebra/embriologia
6.
FASEB J ; 35(7): e21713, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34105201

RESUMO

Syrian golden hamsters (Mesocricetus auratus) infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) manifests lung pathology. In this study, efforts were made to check the infectivity of a local SARS-CoV-2 isolate in a self-limiting and non-lethal hamster model and evaluate the differential expression of lung proteins during acute infection and convalescence. The findings of this study confirm the infectivity of this isolate in vivo. Analysis of clinical parameters and tissue samples show the pathophysiological manifestation of SARS-CoV-2 infection similar to that reported earlier in COVID-19 patients and hamsters infected with other isolates. However, diffuse alveolar damage (DAD), a common histopathological feature of human COVID-19 was only occasionally noticed. The lung-associated pathological changes were very prominent on the 4th day post-infection (dpi), mostly resolved by 14 dpi. Here, we carried out the quantitative proteomic analysis of the lung tissues from SARS-CoV-2-infected hamsters on day 4 and day 14 post-infection. This resulted in the identification of 1585 proteins of which 68 proteins were significantly altered between both the infected groups. Pathway analysis revealed complement and coagulation cascade, platelet activation, ferroptosis, and focal adhesion as the top enriched pathways. In addition, we also identified altered expression of two pulmonary surfactant-associated proteins (Sftpd and Sftpb), known for their protective role in lung function. Together, these findings will aid in understanding the mechanism(s) involved in SARS-CoV-2 pathogenesis and progression of the disease.


Assuntos
COVID-19/metabolismo , COVID-19/patologia , Interações Hospedeiro-Patógeno , Pulmão/metabolismo , Pulmão/virologia , Proteômica , SARS-CoV-2/patogenicidade , Animais , COVID-19/virologia , Cricetinae , Modelos Animais de Doenças , Feminino , Pulmão/patologia , Masculino , Proteoma/análise , Proteoma/biossíntese , Reprodutibilidade dos Testes , Carga Viral
7.
Mol Biol Rep ; 48(9): 6491-6501, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34460062

RESUMO

BACKGROUND: The physiological significance of a large family of heat-shock proteins (HSPs), comprised of the cytosolic HSP90A and the endoplasmic reticulum component of HSPB, is evident in prokaryotes and eukaryotes. The HSP90A is believed to play critical roles in diverse physiological functions of cell viability and chromosomal stability including stress management. Heightened abundance of hsp90ß transcript was documented in Channa striatus, a freshwater fish, which is capable of surviving within an extremely hypoxic environment. METHODS AND RESULTS: To better understand the mechanism of hsp90ß gene expression, we investigated its genomic organization. Eleven exons were identified, including a long upstream intron with a remarkable similarity with human, but not with chicken counterpart. Dual-luciferase assays identified promoter activity in a 1366 bp 5'-flanking segment beyond the transcription initiation site. Examination detected a minimal promoter of 754 bp containing a TATA-box, CAAT-enhancer in addition to providing clues regarding other enhancer and repressor elements. The driving capability of this minimal promoter was further validated by its binding ability with TATA-box binding protein and the generation of GFP expressing transgenic zebrafish (F2). Further, deletion of an inverted HIF (hypoxia inducible factor) motif RCGTG (upstream of the TATA-box) dramatically reduced luciferase expression in a hypoxic environment (CoCl2 treated cultivable cells) and was identified as a cis-acting HIF responsive element, necessary for the hypoxia-induced expression. CONCLUSIONS: The results obtained herein provide an insight regarding how hsp90ß gene expression is controlled by HIF responsive element in teleost both during hypoxia stress management and normal physiological functions, and suggested that the hsp90ß gene promoter could be used as a potential candidate for generating ornamental and food-fish transgenics.


Assuntos
Hipóxia Celular/genética , Deleção de Genes , Regulação da Expressão Gênica , Proteínas de Choque Térmico HSP90/genética , Fator 1 Induzível por Hipóxia/genética , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Hipóxia Celular/efeitos dos fármacos , Cobalto/farmacologia , Éxons , Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Íntrons , Luciferases/genética , Luciferases/metabolismo , Regiões Promotoras Genéticas , Proteína de Ligação a TATA-Box/metabolismo , Transfecção , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/metabolismo
9.
FASEB J ; 30(6): 2311-23, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26939791

RESUMO

C-type lectin family 14, member A (CLEC14A), is a single-pass transmembrane glycoprotein that is overexpressed in tumor endothelial cells, and it promotes sprouting angiogenesis and modulates endothelial function via interactions with extracellular matrix proteins. Here, we show that CLEC14A is cleaved by rhomboid-like protein 2 (RHBDL2), one of 3 catalytic mammalian rhomboid-like (RHBDL) proteases, but that it is not cleaved by RHBDL1 or -3. Site-directed mutagenesis identified the precise site at which RHBDL2 cleaves CLEC14A, and targeted, small interfering RNAs that knockdown endogenous CLEC14A and RHBDL2 in human endothelial cells validated the specificity of CLEC14A shedding by RHBDL2. Loss of endogenous cleaved CLEC14A increased endothelial migration 2-fold, whereas that addition of recombinant cleaved CLEC14A inhibited the sprouting of human and murine endothelial cells 3-fold in several in vitro models. We assessed the in vivo role of cleaved CLEC14A in angiogenesis by using the rodent subcutaneous sponge implant model, and we found that CLEC14A protein inhibited vascular density by >50%. Finally, we show that cleaved CLEC14A binds to sprouting endothelial tip cells. Our data show that the ectodomain of CLEC14A regulates sprouting angiogenesis and suggests a role for RHBDL2 in endothelial function.-Noy, P. J., Swain, R. K., Khan, K., Lodhia, P., Bicknell, R. Sprouting angiogenesis is regulated by shedding of the C-type lectin family 14, member A (CLEC14A) ectodomain, catalyzed by rhomboid-like 2 protein (RHBDL2).


Assuntos
Moléculas de Adesão Celular/metabolismo , Endopeptidases/metabolismo , Células Endoteliais/fisiologia , Lectinas Tipo C/metabolismo , Proteínas de Membrana/metabolismo , Neovascularização Fisiológica/fisiologia , Serina Proteases/metabolismo , Sequência de Aminoácidos , Animais , Fenômenos Biomecânicos , Moléculas de Adesão Celular/genética , Movimento Celular/fisiologia , Endopeptidases/genética , Regulação da Expressão Gênica/fisiologia , Humanos , Lectinas Tipo C/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Ligação Proteica , Domínios Proteicos , Serina Endopeptidases , Serina Proteases/genética
10.
J Cell Sci ; 125(Pt 6): 1420-8, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22275430

RESUMO

The process of angiogenesis requires endothelial cells (ECs) to undergo profound changes in shape and polarity. Although this must involve remodelling of the EC cytoskeleton, little is known about this process or the proteins that control it. We used a co-culture assay of angiogenesis to examine the cytoskeleton of ECs actively undergoing angiogenic morphogenesis. We found that elongation of ECs during angiogenesis is accompanied by stabilisation of microtubules and their alignment into parallel arrays directed at the growing tip. In other systems, similar microtubule alignments are mediated by the formin family of cytoskeletal regulators. We screened a library of human formins and indentified formin-like 3 (FMNL3; also known as FRL2) as a crucial regulator of EC elongation during angiogenesis. We showed that activated FMNL3 triggers microtubule alignment and that FMNL3 is required for this alignment during angiogenic morphogenesis. FMNL3 was highly expressed in the ECs of zebrafish during development and embryos that were depleted for FMNL3 showed profound defects in developmental angiogenesis that were rescued by expression of the human gene. We conclude that FMNL3 is a new regulator of endothelial microtubules during angiogenesis and is required for the conversion of quiescent ECs into their elongated angiogenic forms.


Assuntos
Citoesqueleto/fisiologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Proteínas de Membrana/genética , Neovascularização Fisiológica/genética , Proteínas/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Animais , Técnicas de Cocultura , Forminas , Células Endoteliais da Veia Umbilical Humana , Humanos , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
11.
Phytomedicine ; 123: 155181, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38091824

RESUMO

BACKGROUND: Triple negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and exhibits high rate of chemoresistance, metastasis, and relapse. This can be attributed to the failure of conventional therapeutics to target a sub-population of slow cycling or quiescent cells called as cancer stem cells (CSCs). Therefore, elimination of CSCs is essential for effective TNBC treatment. PURPOSE: Research suggests that breast CSCs exhibit elevated glycolytic metabolism which directly contributes in maintenance of stemness, self-renewability and chemoresistance as well as in tumor progression. Therefore, this study aimed to target rewired metabolism which can serve as Achilles heel for CSCs population and have far reaching effect in TNBC treatment. METHODS: We used two preclinical models, zebrafish and nude mice to evaluate the fate of nanoparticles as well as the therapeutic efficacy of both piperlongumine (PL) and its nanomedicine (PL-NPs). RESULTS: In this context, we explored a phytochemical piperlongumine (PL) which has potent anti-cancer properties but poor pharmacokinetics impedes its clinical translation. So, we developed PLGA based nanomedicine for PL (PL-NPs), and demonstrated that it overcomes the pharmacokinetic limitations of PL, along with imparting advantages of selective tumor targeting through Enhanced Permeability and Retention (EPR) effect in zebrafish xenograft model. Further, we demonstrated that PL-NPs efficiently inhibit glycolysis in CSCs through inhibition of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) by modulating glutathione S-transferase pi 1 (GSTP1) and upregulation of fructose-1,6-bisphosphatase 1 (FBP1), a rate-limiting enzyme in gluconeogenesis. We also illustrated that inhibition of glycolysis results in overall tumor regression in two preclinical models. CONCLUSION: This study discusses novel mechanism of action by which PL acts on CSCSs. Taken together our study provides insight into development of PL based nanomedicine which could be exploited in clinics to achieve complete eradication of TNBC by targeting CSCs.


Assuntos
Benzodioxóis , Neoplasias de Mama Triplo Negativas , Animais , Camundongos , Humanos , Neoplasias de Mama Triplo Negativas/metabolismo , Peixe-Zebra/metabolismo , Nanomedicina , Camundongos Nus , Linhagem Celular Tumoral , Recidiva Local de Neoplasia/metabolismo , Células-Tronco Neoplásicas , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/farmacologia , Gliceraldeído-3-Fosfato Desidrogenases/uso terapêutico , Glicólise
12.
Transl Res ; 268: 63-78, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499286

RESUMO

Cisplatin alone or in combination with 5FU and docetaxel is the preferred chemotherapy regimen for advanced-stage OSCC patients. However, its use has been linked to recurrence and metastasis due to the development of drug resistance. Therefore, sensitization of cancer cells to conventional chemotherapeutics can be an effective strategy to overcome drug resistance. Piperlongumine (PL), an alkaloid, have shown anticancer properties and sensitizes numerous neoplasms, but its effect on OSCC has not been explored. However, low aqueous solubility and poor pharmacokinetics limit its clinical application. Therefore, to improve its therapeutic efficacy, we developed piperlongumine-loaded PLGA-based smart nanoparticles (smart PL-NPs) that can rapidly release PL in an acidic environment of cancer cells and provide optimum drug concentrations to overcome chemoresistance. Our results revealed that smart PL-NPs has high cellular uptake in acidic environment, facilitating the intracellular delivery of PL and sensitizing cancer cells to cisplatin, resulting in synergistic anticancer activity in vitro by increasing DNA damage, apoptosis, and inhibiting drug efflux. Further, we have mechanistically explored the Hippo-YAP signaling pathway, which is the critical mediator of chemoresistance, and investigated the chemosensitizing effect of PL in OSCC. We observed that PL alone and in combination with cisplatin significantly inhibits the activation of YAP and its downstream target genes and proteins. In addition, the combination of cisplatin with smart PL-NPs significantly inhibited tumor growth in two preclinical models (patient-derived cell based nude mice and zebrafish xenograft). Taken together, our findings suggest that smart PL-NPs with cisplatin will be a novel formulation to reverse cisplatin resistance in patients with advanced OSCC.


Assuntos
Cisplatino , Dioxolanos , Resistencia a Medicamentos Antineoplásicos , Via de Sinalização Hippo , Neoplasias Bucais , Nanopartículas , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Humanos , Cisplatino/farmacologia , Nanopartículas/química , Dioxolanos/farmacologia , Dioxolanos/administração & dosagem , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Animais , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Neoplasias Bucais/metabolismo , Linhagem Celular Tumoral , Transdução de Sinais/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Peixe-Zebra , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Camundongos Nus , Camundongos , Proteínas de Sinalização YAP , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Piperidonas
13.
Cell Commun Signal ; 11: 89, 2013 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-24252524

RESUMO

BACKGROUND: Activation of the Wnt signalling cascade is primarily based on the interplay between Wnt ligands, their receptors and extracellular modulators. One prominent family of extracellular modulators is represented by the SFRP (secreted Frizzled-related protein) family. These proteins have significant similarity to the extracellular domain of Frizzled receptors, suggesting that they bind Wnt ligands and inhibit signalling. The SFRP-type protein Fz4-v1, a splice variant of the Frizzled-4 receptor found in humans and Xenopus, was shown to augment Wnt/ß-catenin signalling, and also interacts with those Wnt ligands that act on ß-catenin-independent Wnt pathways. FINDINGS: Here we show that Xenopus Fz4-v1 can activate and inhibit the ß-catenin-dependent Wnt pathway. Gain-of-function experiments revealed that high Wnt/ß-catenin activity is inhibited by low and high concentrations of Fz4-v1. In contrast, signals generated by low amounts of Wnt ligands were enhanced by low concentrations of Fz4-v1 but were repressed by high concentrations. This biphasic activity of Fz4-v1 was not observed in non-canonical Wnt signalling. Fz4-v1 enhanced ß-catenin-independent Wnt signalling triggered by either low or high doses of Wnt11. Antisense morpholino-mediated knock-down experiments demonstrated that in early Xenopus embryos Fz4-v1 is required for the migration of cranial neural crest cells and for the development of the dorsal fin. CONCLUSIONS: For the first time, we show that a splice variant of the Frizzled-4 receptor modulates Wnt signalling in a dose-dependent, biphasic manner. These results also demonstrate that the cystein-rich domain (CRD), which is shared by Fz4-v1 and SFRPs, is sufficient for the biphasic activity of these secreted Wnt modulators.


Assuntos
Receptores Frizzled/fisiologia , Via de Sinalização Wnt/fisiologia , Proteínas de Xenopus/fisiologia , Animais , Embrião não Mamífero , Desenvolvimento Embrionário/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Isoformas de Proteínas , Xenopus laevis
14.
Transl Oncol ; 35: 101729, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37369156

RESUMO

Multiple myeloma (MM) is an incurable plasma cell neoplasm. Despite several effective frontline therapeutic regimens, including Bortezomib (BTZ), relapse is almost inevitable; therefore, better therapeutic modalities to improve the outcomes are needed. Cyclin-dependent kinases (CDKs) are an essential constituent of the cellular transcriptional machinery and tumors including MM are critically dependent on transcription to maintain their oncogenic state. In the present study, we explored the efficacy of THZ1, a covalent CDK7 inhibitor in MM treatment using Bortezomib resistant (H929BTZR) cells and zebrafish xenografts. THZ1 showed anti-myeloma activity in the models of MM but had no effect on healthy CD34+ cells. THZ1 suppresses phosphorylation of carboxy-terminal domain of RNA polymerase II and downregulates the transcription of BCL2 family of proteins both in H929BTZS and H929BTZR cells leading to G1/S arrest and apoptosis. THZ1 mediates inhibition of bone marrow stromal cells-induced proliferation and activation of NF-kB signaling. The data derived from zebrafish xenografts of MM demonstrate that THZ1 combined with BTZ synergistically reduces tumor growth in zebrafish embryos. Collectively, our results reveal that THZ1 alone as well as in combination with BTZ has effective anti-myeloma activity.

15.
Mol Ther Nucleic Acids ; 34: 102031, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37771911

RESUMO

Triple-negative breast cancer (TNBC) harbors a high percentage of breast cancer stem-like cells (BCSCs) that significantly contribute to poor prognosis, metastasis, and relapse of the disease. Thus, targeting BCSCs could be a promising approach to combat TNBC. In this context, we investigated nimbolide (Nim), a limonoid triterpenoid that has potent anticancer properties, but poor pharmacokinetics and low bioavailability limit its therapeutic application. So, to enhance the therapeutic potential of Nim, Nim-encapsulated poly(lactic-co-glycolic acid) (PLGA) nanoparticles (Nim NPs) were formulated and the anticancer stem cell (CSC) effects evaluated in vitro and in vivo. In vitro studies suggested that Nim NPs significantly inhibited several inherent characteristics of BCSCs, such as stemness, self-renewability, chemoresistance, epithelial-to-mesenchymal transition (EMT), and migration in comparison to native Nim. Next, the mechanism behind the anti-CSC effect of Nim was explored. Mechanistically, we found that Nim epigenetically restores tumor suppressor gene secreted frizzled-related protein 1 (SFRP1) expression by downregulating DNA methyltransferases (DNMTs), leading to Wnt/ß-catenin signaling inhibition. Further, in vivo results demonstrated that Nim NPs showed enhanced anti-tumor and anti-metastatic effects compared to native Nim in two preclinical models without any systemic toxicity. Overall, these findings provide proof of concept that Nim-based phytonanomedicine can inhibit BCSCs by epigenetic reprogramming of the DNMTs-SFRP1-Wnt/ß-catenin signaling axis.

16.
Sci Rep ; 13(1): 14560, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37666993

RESUMO

Frequent mutation and variable immunological protection against vaccination is a common feature for COVID-19 pandemic. Early detection and confinement remain key to controlling further spread of infection. In response, we have developed an aptamer-based system that possesses both diagnostic and therapeutic potential towards the virus. A random aptamer library (~ 1017 molecules) was screened using systematic evolution of ligands by exponential enrichment (SELEX) and aptamer R was identified as a potent binder for the SARS-CoV-2 spike receptor binding domain (RBD) using in vitro binding assay. Using a pseudotyped viral entry assay we have shown that aptamer R specifically inhibited the entry of a SARS-CoV-2 pseudotyped virus in HEK293T-ACE2 cells but did not inhibit the entry of a Vesicular Stomatitis Virus (VSV) glycoprotein (G) pseudotyped virus, hence establishing its specificity towards SARS-CoV-2 spike protein. The antiviral potential of aptamers R and J (same central sequence as R but lacking flanked primer regions) was tested and showed 95.4% and 82.5% inhibition, respectively, against the SARS-CoV-2 virus. Finally, intermolecular interactions between the aptamers and the RBD domain were analyzed using in silico docking and molecular dynamics simulations that provided additional insight into the binding and inhibitory action of aptamers R and J.


Assuntos
COVID-19 , Inibidores da Fusão de HIV , Humanos , SARS-CoV-2 , Células HEK293 , Pandemias , Ligantes , Oligonucleotídeos , Teste para COVID-19
17.
J Vis Exp ; (186)2022 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-36094281

RESUMO

Zebrafish are extensively used in several kinds of research because they are one of the easily maintained vertebrate models and exhibit several features of a unique and convenient model system. As highly proliferative cells are more susceptible to radiation-induced DNA damage, zebrafish embryos are a front-line in vivo model in radiation research. In addition, this model projects the effect of radiation and different drugs within a short time, along with major biological events and associated responses. Several cancer studies have used zebrafish, and this protocol is based on the use of radiation modifiers in the context of radiotherapy and cancer. This method can be readily used to validate the effects of different drugs on irradiated and control (non-irradiated) embryos, thus identifying drugs as radio sensitizing or protective drugs. Although this methodology is used in most drug screening experiments, the details of the experiment and the toxicity assessment with the background of X-ray radiation exposure are limited or only briefly addressed, making it difficult to perform. This protocol addresses this issue and discusses the procedure and toxicity evaluation with a detailed illustration. The procedure describes a simple approach for using zebrafish embryos for radiation studies and radiation-based drug screening with much reliability and reproducibility.


Assuntos
Peixe-Zebra , Animais , Avaliação Pré-Clínica de Medicamentos , Larva/efeitos da radiação , Reprodutibilidade dos Testes , Raios X , Peixe-Zebra/genética
18.
Front Immunol ; 13: 848335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572555

RESUMO

Background: SARS-CoV2 infection in patients with comorbidities, particularly T2DM, has been a major challenge globally and has been shown to be associated with high morbidity and mortality. Here, we did whole blood immunophenotyping along with plasma cytokine, chemokine, antibody isotyping, and viral load from oropharyngeal swab to understand the immune pathology in the T2DM patients infected with SARS-CoV2. Methods: Blood samples from 25 Covid-19 positive patients having T2DM, 10 Covid-19 positive patients not having T2DM, and 10 Covid-19 negative, non-diabetic healthy controls were assessed for various immune cells by analyzing for their signature surface proteins in mass cytometry. Circulating cytokines, chemokines, and antibody isotypes were determined from plasma while viral copy number was determined from oropharyngeal swabs. All our representative data corroborated with laboratory findings. Results: Our observations encompass T2DM patients having elevated levels of both type I and type II cytokines and higher levels of circulating IgA, IgM, IgG1, and IgG2 as compared to NDM and healthy volunteers. They also displayed higher percentages of granulocytes, mDCs, plasmablasts, Th2-like cells, CD4+ EM cells, and CD8+ TE cells as compared to healthy volunteers. T2DM patients also displayed lower percentages of pDCs, lymphocytes, CD8+ TE cells, CD4+, and CD8+ EM. Conclusion: Our study demonstrated that patients with T2DM displayed higher inflammatory markers and a dysregulated anti-viral and anti-inflammatory response when compared to NDM and healthy controls and the dysregulated immune response may be attributed to meta inflammation.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Quimiocinas , Citocinas , Humanos , RNA Viral , SARS-CoV-2
19.
Oncogene ; 41(45): 4929-4940, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36182968

RESUMO

Cisplatin, 5FU and docetaxel (TPF) are the most common chemotherapy regimen used for advanced OSCC. However, many cancer patients experience relapse, continued tumor growth, and spread due to drug resistance, which leads to treatment failure and metastatic disease. Here, using a CRISPR/Cas9 based kinome knockout screening, Misshapen-like kinase 1 (MINK1) is identified as an important mediator of 5FU resistance in OSCC. Analysis of clinical samples demonstrated significantly higher MINK1 expression in the tumor tissues of chemotherapy non-responders as compared to chemotherapy responders. The nude mice and zebrafish xenograft experiments indicate that knocking out MINK1 restores 5FU mediated cell death in chemoresistant OSCC. An antibody based phosphorylation array screen revealed MINK1 as a negative regulator of p53. Mechanistically, MINK1 modulates AKT phosphorylation at Ser473, which enables p-MDM2 (Ser 166) mediated degradation of p53. We also identified lestaurtinib as a potent inhibitor of MINK1 kinase activity. The patient derived TPF resistant cell based xenograft data suggest that lestaurtinib restores 5FU sensitivity and facilitates a significant reduction of tumor burden. Overall, our study suggests that MINK1 is a major driver of 5FU resistance in OSCC. The novel combination of MINK1 inhibitor lestaurtinib and 5FU needs further clinical investigation in advanced OSCC.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Proteína Supressora de Tumor p53 , Camundongos , Animais , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Camundongos Nus , Peixe-Zebra/metabolismo , Recidiva Local de Neoplasia/tratamento farmacológico , Cisplatino/farmacologia , Fluoruracila/uso terapêutico , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Serina-Treonina Quinases/genética
20.
Front Microbiol ; 13: 856913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35847066

RESUMO

The emergence of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) as a serious pandemic has altered the global socioeconomic dynamics. The wide prevalence, high death counts, and rapid emergence of new variants urge for the establishment of research infrastructure to facilitate the rapid development of efficient therapeutic modalities and preventive measures. In agreement with this, SARS-CoV-2 strains were isolated from patient swab samples collected during the first COVID-19 wave in Odisha, India. The viral isolates were adapted to in vitro cultures and further characterized to identify strain-specific variations in viral growth characteristics. The neutralization susceptibility of viral isolates to vaccine-induced antibodies was determined using sera from individuals vaccinated in the Government-run vaccine drive in India. The major goal was to isolate and adapt SARS-CoV-2 viruses in cell culture with minimum modifications to facilitate research activities involved in the understanding of the molecular virology, host-virus interactions, drug discovery, and animal challenge models that eventually contribute toward the development of reliable therapeutics.

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