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1.
Front Public Health ; 12: 1332511, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560431

RESUMO

Introduction: This study empirically investigates the attitude of tobacco and alcohol consumers towards health insurance purchase in India. The study aims to determine the factors which plays a significant role in determining the purchase intention of health insurance among tobacco and alcohol consumers. Methods: We propose an extended theory of planned behavior (TPB) model comprising factors like attitude, subjective norms, perceived behavior control, perceived usefulness, perceived product risk, and intention to purchase. We collected responses from 420 tobacco and alcohol consumers through a Google Form link shared via different social media platforms. SPSS has been used to perform exploratory factor analysis, whereas AMOS has been used to validate the constructs, confirm the relationships among the variables, and analyze the data. Results: The analysis outcomes demonstrate that subjective norms, perceived product risk, and perceived behavioral control are the factors that have a positive and significant effect on health insurance purchase intention among consumers. Discussion: This research offers valuable insights to the insurance sector, government officials, policymakers, and academicians. Insurance companies may consider the criteria analysed when creating policies to promote the expansion of the health insurance sector.


Assuntos
Intenção , Lobelia , Humanos , Inquéritos e Questionários , Atitude , Seguro Saúde
2.
Cancers (Basel) ; 16(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38610997

RESUMO

Progress in the treatment of multiple myeloma (MM) has resulted in improvement in the survival rate. However, there is still a need for more efficacious and tolerated therapies. We and others have shown that bromodomain-containing protein 9 (BRD9), a member of the non-canonical SWI/SNF chromatin remodeling complex, plays a role in MM cell survival, and targeting BRD9 selectively blocks MM cell proliferation and synergizes with IMiDs. We found that synergy in vitro is associated with the downregulation of MYC and Ikaros proteins, including IKZF3, and overexpression of IKZF3 or MYC could partially reverse synergy. RNA-seq analysis revealed synergy to be associated with the suppression of pathways associated with MYC and E2F target genes and pathways, including cell cycle, cell division, and DNA replication. Stimulated pathways included cell adhesion and immune and inflammatory response. Importantly, combining IMiD treatment and BRD9 targeting, which leads to the downregulation of MYC protein and upregulation of CRBN protein, was able to override IMiD resistance of cells exposed to iberdomide in long-term culture. Taken together, our results support the notion that combination therapy based on agents targeting BRD9 and IKZF3, two established dependencies in MM, represents a promising novel therapeutic strategy for MM and IMiD-resistant disease.

3.
Haematologica ; 109(1): 186-199, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37534528

RESUMO

Despite recent advances in the therapy of diffuse large B-cell lymphoma (DLBCL), many patients are still not cured. Therefore, new therapeutic strategies are needed. The anti-apoptotic B-cell lymphoma 2 (BCL2) gene is commonly dysregulated in DLBCL due to various mechanisms such as chromosomal translocation t(14;18)(q32;q21) and copy number alterations; however, targeting BCL-2 with the selective inhibitor, venetoclax, led to response in only a minority of patients. Thus, we sought to identify a rational combination partner of venetoclax to improve its activity against DLBCL cells. Utilizing a functional assay, dynamic BH3 profiling, we found that the DNA hypomethylating agent decitabine increased mitochondrial apoptotic priming and BCL-2 dependence in DLBCL cells. RNA-sequencing analysis revealed that decitabine suppressed the pro-survival PI3K-AKT pathway and altered the mitochondria membrane composition in DLBCL cell lines. Additionally, it induced a DNA damage response and increased BAX and BAK activities. The combination of decitabine and venetoclax synergistically suppressed proliferation of DLBCL cells both in vitro and in vivo in a DLBCL cell line-derived xenograft mouse model. Our study suggests that decitabine plus venetoclax is a promising combination to explore clinically in DLBCL.


Assuntos
Linfoma Difuso de Grandes Células B , Fosfatidilinositol 3-Quinases , Humanos , Animais , Camundongos , Decitabina/farmacologia , Decitabina/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas c-bcl-2 , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Apoptose
4.
Future Microbiol ; 19: 33-49, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37830931

RESUMO

Aim: Leishmaniasis is characterized by a spectrum of diseases with two main clinical forms, cutaneous and visceral, caused by Leishmania tropica and Leishmania donovani, respectively. Studying Leishmania's interaction with the epithelial barrier at the initial site of a bite is crucial to understanding the establishment of the disease. Materials & methods: To discern parasite-host epithelial interaction, we developed in vitro cellular models involving co-cultures of Leishmania and MDCK epithelial cells. Results: Both L. donovani-MDCK and L. tropica-MDCK co-culture models demonstrated a phenomenon known as atypical anoikis apoptosis, typically identified by distinctive 'flipping in' of cell membranes and disordered cytoskeletal frameworks. Conclusion: This study bridges the gap in the fundamental understanding of the intricate latticework involving vector-Leishmania-host and may inform drug development strategies.


Small parasites called Leishmania are passed to humans through the bites of sandflies. These parasites cause three deadly forms of disease: one that affects the organs, one that causes skin lesions and one that affects organ linings. This study looked at how Leishmania parasites behave when they enter through the skin. We found that when the parasites were in contact with cells, the cells changed their shape and lost contact with neighboring cells. This led to a type of cell death known as anoikis, a Greek term meaning 'homelessness'.


Assuntos
Pessoas Mal Alojadas , Leishmania donovani , Leishmania tropica , Leishmaniose Cutânea , Leishmaniose Visceral , Humanos , Anoikis , Células Epiteliais
5.
Hematol Rep ; 15(4): 608-626, 2023 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-37987319

RESUMO

Acute myeloid leukemia (AML) is a heterogeneous hematological malignancy that is often associated with relapse and drug resistance after standard chemotherapy or targeted therapy, particularly in older patients. Hematopoietic stem cell transplants are looked upon as the ultimate salvage option with curative intent. Adoptive cell therapy using chimeric antigen receptors (CAR) has shown promise in B cell malignancies and is now being investigated in AML. Initial clinical trials have been disappointing in AML, and we review current strategies to improve efficacy for CAR approaches. The extensive number of clinical trials targeting different antigens likely reflects the genetic heterogeneity of AML. The limited number of patients reported in multiple early clinical studies makes it difficult to draw conclusions about CAR safety, but it does suggest that the efficacy of this approach in AML lags behind the success observed in B cell malignancies. There is a clear need not only to improve CAR design but also to identify targets in AML that show limited expression in normal myeloid lineage cells.

6.
iScience ; 26(5): 106637, 2023 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-37192974

RESUMO

Cold shock proteins are characterized by the presence of one or more cold shock domains that bestow them with nucleic acid binding ability. Although cold shock proteins are well characterized in bacteria, plants and humans, there is no information on their existence and role in malaria parasite. Here, we have identified and delineated the function of a cold shock protein of Plasmodium falciparum (Pf) 'PfCoSP'. We demonstrate that PfCoSP exhibits nucleic acid binding properties and regulates gene expression. PfCoSP promotes microtubule assembly by interacting with Pf α/ß tubulin. We identified a human cold shock protein LIN28A inhibitor 'LI71' as a binding partner of PfCoSP which inhibited PfCoSP-DNA and α/ß tubulin interactions and, also inhibited the development of asexual blood stages and gametocyte stage of malaria parasite. Because PfCoSP is essential for parasite survival, characterization of its interacting partners may form the basis for development of future anti-malarials.

7.
Biochem Pharmacol ; 212: 115567, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37088154

RESUMO

Prohibitins (PHBs) are highly conserved pleiotropic proteins as they have been shown to mediate key cellular functions. Here, we characterize PHBs encoding putative genes ofPlasmodium falciparum by exploiting different orthologous models. We demonstrated that PfPHB1 (PF3D7_0829200) and PfPHB2 (PF3D7_1014700) are expressed in asexual and sexual blood stages of the parasite. Immunostaining indicated hese proteins as mitochondrial residents as they were found to be localized as branched structures. We further validated PfPHBs as organellar proteins residing in Plasmodium mitochondria, where they interact with each other. Functional characterization was done in Saccharomyces cerevisiae orthologous model by expressing PfPHB1 and PfPHB2 in cells harboring respective mutants. The PfPHBs functionally complemented the yeast PHB1 and PHB2 mutants, where the proteins were found to be involved in stabilizing the mitochondrial DNA, retaining mitochondrial integrity and rescuing yeast cell growth. Further, Rocaglamide (Roc-A), a known inhibitor of PHBs and anti-cancerous agent, was tested against PfPHBs and as an antimalarial. Roc-A treatment retarded the growth of PHB1, PHB2, and ethidium bromide petite yeast mutants. Moreover, Roc-A inhibited growth of yeast PHBs mutants that were functionally complemented with PfPHBs, validating P. falciparum PHBs as one of the molecular targets for Roc-A. Roc-A treatment led to growth inhibition of artemisinin-sensitive (3D7), artemisinin-resistant (R539T) and chloroquine-resistant (RKL-9) parasites in nanomolar ranges. The compound was able to retard gametocyte and oocyst growth with significant morphological aberrations. Based on our findings, we propose the presence of functional mitochondrial PfPHB1 and PfPHB2 in P. falciparum and their druggability to block parasite growth.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Parasitos , Humanos , Animais , Plasmodium falciparum/genética , Proibitinas , Saccharomyces cerevisiae/genética , Malária Falciparum/parasitologia , Artemisininas/farmacologia , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico
8.
Nat Commun ; 14(1): 1452, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36922497

RESUMO

This multi-centre, non-randomized, open-label, phase II trial (NCT03016338), assessed niraparib monotherapy (cohort 1, C1), or niraparib and dostarlimab (cohort 2, C2) in patients with recurrent serous or endometrioid endometrial carcinoma. The primary endpoint was clinical benefit rate (CBR), with ≥5/22 overall considered of interest. Secondary outcomes were safety, objective response rate (ORR), duration of response, progression free survival and overall survival. Translational research was an exploratory outcome. Potential biomarkers were evaluated in archival tissue by immunohistochemistry and next generation sequencing panel. In C1, 25 patients were enrolled, and CBR was 20% (95% CI: 9-39) with median clinical benefit duration of 5.3 months. The ORR was 4% (95% CI: 0-20). In C2, 22 patients were enrolled, and the CBR was 31.8% (95% CI: 16-53) with median clinical benefit duration of 6.8 months. The ORR was 14% (95% CI: 3-35). No new safety signals were detected. No significant association was detected between clinical benefit and IHC markers (PTEN, p53, MMR, PD-L1), or molecular profiling (PTEN, TP53, homologous recombination repair genes). In conclusion, niraparib monotherapy did not meet the efficacy threshold. Niraparib in combination with dostarlimab showed modest activity.


Assuntos
Neoplasias do Endométrio , Recidiva Local de Neoplasia , Feminino , Humanos , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/patologia , Biomarcadores
9.
Gene ; 869: 147396, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36990255

RESUMO

Iron-sulfur (Fe-S) cluster containing proteins have been assigned roles in various essential cellular processes, such as regulation of gene expression, electron transfer, sensing of oxygen and balancing free radical chemistry. However, their role as the drug target remains sparse. Recently the screening of protein alkylation targets for artemisinin in Plasmodium falciparum led to identification of Dre2, a protein involved in redox mechanism for the cytoplasmic Fe-S cluster assembly in different organisms. In the present study, to further explore the interaction between artemisinin and Dre2, we have expressed the Dre2 protein of both P. falciparum and P. vivax in E. coli. The opaque brown colour of the IPTG induced recombinant Plasmodium Dre2 bacterial pellet, suggested iron accumulation as confirmed by the ICP-OES analysis. In addition, overexpression of rPvDre2 in E. coli reduced its viability, growth and increased the ROS levels of bacterial cells, which in turn led to an increase in expression of stress response genes of E. coli such as recA, soxS, mazF. Moreover, the overexpression of rDre2 induced cell death could be rescued by treatment with Artemisinin derivatives suggesting their interaction. The interaction between DHA and PfDre2 was later demonstrated by CETSA and microscale thermophoresis. Overall, this study suggests that Dre2 is the probable target of Artemisinin and the antimalarial activity of DHA/Artemether could also be due to yet unidentified molecular mechanism altering the Dre2 activity in addition to inducing DNA and protein damage.


Assuntos
Artemisininas , Proteínas de Escherichia coli , Proteínas Ferro-Enxofre , Plasmodium , Artemisininas/farmacologia , Proteínas de Ligação a DNA/metabolismo , Endorribonucleases , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Ferro/metabolismo , Proteínas Ferro-Enxofre/genética , Proteínas Ferro-Enxofre/química , Proteínas Ferro-Enxofre/metabolismo , Plasmodium/metabolismo , Enxofre/metabolismo
11.
Artigo em Inglês | MEDLINE | ID: mdl-36613123

RESUMO

With the proliferation of technological tools and the advancement in electronic devices and accessories, consumers across the world are changing and upgrading their electronic devices at an alarming rate. However, these developments have raised concerns related to electronic waste (E-waste). E-wastes contain toxic substances which may have a negative impact on both humans and the environment. This issue needs to be addressed by the research community, i.e., what would be the best way to get rid of existing devices? It is clear that countries need to work towards a more sustainable consumption pattern and consumers need to change their behaviour. The present study focuses on sustainable behaviour of consumers in terms of e-waste management. In this context, the study attempts to explore the factors influencing e-waste management among young consumers. In the present study, the Theory of Planned Behavior is extended by including the additional factors Government Policy, Environmental Concern, Financial Benefits and Awareness. A researcher-controlled sampling was employed to collect data from 524 respondents. Partial least square structural equation modelling (PLS-SEM) was used to validate the questionnaire constructs and confirm the relationships among the variables. The findings of the study suggest a significant role for government policy, financial benefits, environmental concerns, attitude, subjective norms, and perceived behavioural control in determining young consumers' behavioural intentions toward the management of e-waste. The study findings have implications for both researchers and marketing practitioners.


Assuntos
Resíduo Eletrônico , Gerenciamento de Resíduos , Humanos , Atitude , Intenção , Inquéritos e Questionários , Comportamento do Consumidor
13.
Antimicrob Agents Chemother ; 66(12): e0039222, 2022 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-36374050

RESUMO

The emergence of Plasmodium falciparum resistance raises an urgent need to find new antimalarial drugs. Here, we report the rational repurposing of the anti-hepatitis C virus drug, alisporivir, a nonimmunosuppressive analog of cyclosporin A, against artemisinin-resistant strains of P. falciparum. In silico docking studies and molecular dynamic simulation predicted strong interaction of alisporivir with PfCyclophilin 19B, confirmed through biophysical assays with a Kd value of 354.3 nM. Alisporivir showed potent antimalarial activity against chloroquine-resistant (PfRKL-9 with resistance index [Ri] 2.14 ± 0.23) and artemisinin-resistant (PfKelch13R539T with Ri 1.15 ± 0.04) parasites. The Ri is defined as the ratio between the IC50 values of the resistant line to that of the sensitive line. To further investigate the mechanism involved, we analyzed the expression level of PfCyclophilin 19B in artemisinin-resistant P. falciparum (PfKelch13R539T). Semiquantitative real-time transcript, Western blot, and immunofluorescence analyses confirmed the overexpression of PfCyclophilin 19B in PfKelch13R539T. A 50% inhibitory concentration in the nanomolar range, together with the targeting of PfCyclophilin 19B, suggests that alisporivir can be used in combination with artemisinin. Since artemisinin resistance slows the clearance of ring-stage parasites, we performed a ring survival assay on artemisinin-resistant strain PfKelch13R539T and found significant decrease in parasite survival with alisporivir. Alisporivir was found to act synergistically with dihydroartemisinin and increase its efficacy. Furthermore, alisporivir exhibited antimalarial activity in vivo. Altogether, with the rational target-based Repurposing of alisporivir against malaria, our results support the hypothesis that targeting resistance mechanisms is a viable approach toward dealing with drug-resistant parasite.


Assuntos
Antimaláricos , Artemisininas , Malária Falciparum , Malária , Humanos , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Ciclosporina/farmacologia , Ciclosporina/uso terapêutico , Reposicionamento de Medicamentos , Resistência a Medicamentos , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum
14.
Biochem Pharmacol ; 205: 115287, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36209839

RESUMO

The increased resistance of human malaria parasite Plasmodium falciparum (Pf) to currently used drugs necessities the development of novel anti-malarials. Here, we examine the potential of erythritol, a sugar substitute for therapeutic intervention. Erythritol is a permeant of Plasmodium falciparum aquaglyceroporin (PfAQP) which is a multifunctional channel responsible for maintaining hydro-homeostasis. We show that erythritol effectively inhibited growth and progression of asexual blood stage malaria parasite, and effect invasion and egress processes. It also inhibited the liver stage (sporozoites) and transmission stage parasite (gametocytes) development. Interestingly, erythritol inhibited in vivo growth of malaria parasite in mouse experimental model. It was more effective in inhibiting parasite growth both in vivo and in vitro when tested together with a known anti-malarial 'artesunate'. Additionally, erythritol showed cytokine-modulating effect which suggests its direct effect on the host immune system. Ammonia detection assay demonstrated that erythritol uptake effects the amount of ammonia release across the parasite. Our functional complementation assays suggest that PfAQP expression in yeast mutant restores its growth in hyperosmotic conditions but showed reduced growth in the presence of erythritol. Osmotic lysis assay suggests that erythritol creates osmotic stress for killing the parasite. Overall, our data bestow erythritol as a promising lead compound with an attractive antimalarial profile and could possibly be combined with known drugs without losing its efficacy. We propose the use of erythritol based sweet candies for protection against malaria specially in children living in the endemic area.


Assuntos
Antimaláricos , Aquagliceroporinas , Criança , Camundongos , Humanos , Animais , Antimaláricos/farmacologia , Plasmodium falciparum , Aquagliceroporinas/farmacologia , Eritritol/farmacologia , Edulcorantes , Amônia/farmacologia , Citocinas/farmacologia
16.
J Obstet Gynaecol India ; 72(Suppl 1): 319-325, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35928063

RESUMO

Objective: To evaluate the prognostic role of pretreatment CD4 + , CD8 + T lymphocytes in predicting response to definite chemo radiotherapy in advanced cervical cancer. Design: A hospital-based prospective one-year follow-up study. Method: This observational study was conducted on 74 patients with advanced cervical cancer. Pretreatment CD4 + and CD8 + levels in cervical cancer tissue and peripheral blood was noted and quantitatively assessed in patients with complete remission or persistent disease after one year of follow-up. Results: There was a statistically significant association of tumour volume with the remission or persistence of disease. In peripheral blood, mean CD4 + score and CD4 + /CD8 + ratio were significantly higher while mean CD8 + score is significantly lower in patients with remission. Similar results were seen in tumour tissue as well. On Receiver Operating Curve analysis, the cut-off value of CD4 + , CD8 + and CD4 + /CD8 + ratio in predicting remission or persistent disease in peripheral blood was 20.09, 18.51 and 0.41 while in tumor tissue was 19.71, 20.99 and 0.20, respectively. Conclusion: The patients with tumor volume < 100 cm 2 have much higher chances of remission. The patients with higher CD4 + and CD4 + / CD8 + ratio, both in peripheral blood as well as tumor tissue, have higher chances of remission. The cut-off value of CD4 + , CD8 + and CD4 + /CD8 + ratio in predicting remission or persistent disease in peripheral blood was 20.09, 18.51 and 0.41 while in tumor tissue was 19.71, 20.99 and 0.20, respectively.

17.
ACS Infect Dis ; 8(10): 2106-2118, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36044540

RESUMO

Phosphorylation and other post-translational modifications of red blood cell (RBC) proteins govern membrane function and have a role in the invasion of RBCs by the malaria parasite, Plasmodium falciparum. Furthermore, a percentage of RBC proteins are palmitoylated, although the functional consequences are unknown. We establish dynamic palmitoylation of 118 RBC membrane proteins using click chemistry and acyl biotin exchange (ABE)-coupled LC-MS/MS and characterize their involvement in controlling membrane organization and parasite invasion. RBCs were treated with a generic palmitoylation inhibitor, 2-bromopalmitate (2-BMP), and then analyzed using ABE-coupled LC-MS/MS. Only 42 of the 118 palmitoylated proteins detected were palmitoylated in the 2-BMP-treated sample, indicating that palmitoylation is dynamically regulated. Interestingly, membrane receptors such as semaphorin 7A, CR1, and ABCB6, which are known to be involved in merozoite interaction with RBCs and parasite invasion, were found to be dynamically palmitoylated, including the blood group antigen, Kell, whose antigenic abundance was significantly reduced following 2-BMP treatment. To investigate the involvement of Kell in merozoite invasion of RBCs, a specific antibody to its extracellular domain was used. The antibody targeting Kell inhibited merozoite invasion of RBCs by 50%, implying a role of Kell, a dynamically palmitoylated potent host-derived receptor, in parasite invasion. Furthermore, a significant reduction in merozoite contact with the RBC membrane and a consequent decrease in parasite invasion following 2-BMP treatment demonstrated that palmitoylation does indeed regulate RBC susceptibility to parasite invasion. Taken together, our findings revealed the dynamic palmitoylome of RBC membrane proteins and its role in P. falciparum invasion.


Assuntos
Antígenos de Grupos Sanguíneos , Malária Falciparum , Parasitos , Semaforinas , Animais , Biotina/metabolismo , Antígenos de Grupos Sanguíneos/metabolismo , Cromatografia Líquida , Lipoilação , Proteínas de Membrana/metabolismo , Merozoítos/metabolismo , Parasitos/metabolismo , Plasmodium falciparum/metabolismo , Semaforinas/metabolismo , Espectrometria de Massas em Tandem
18.
Blood Cancer J ; 12(7): 110, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35853853

RESUMO

Bromodomain-containing protein 9 (BRD9), an essential component of the SWI/SNF chromatin remodeling complex termed ncBAF, has been established as a therapeutic target in a subset of sarcomas and leukemias. Here, we used novel small molecule inhibitors and degraders along with RNA interference to assess the dependency on BRD9 in the context of diverse hematological malignancies, including acute myeloid leukemia (AML), acute lymphoblastic leukemia (ALL), and multiple myeloma (MM) model systems. Following depletion of BRD9 protein, AML cells undergo terminal differentiation, whereas apoptosis was more prominent in ALL and MM. RNA-seq analysis of acute leukemia and MM cells revealed both unique and common signaling pathways affected by BRD9 degradation, with common pathways including those associated with regulation of inflammation, cell adhesion, DNA repair and cell cycle progression. Degradation of BRD9 potentiated the effects of several chemotherapeutic agents and targeted therapies against AML, ALL, and MM. Our findings support further development of therapeutic targeting of BRD9, alone or combined with other agents, as a novel strategy for acute leukemias and MM.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Mieloma Múltiplo , Fatores de Transcrição , Antineoplásicos/farmacologia , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Interferência de RNA , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
19.
Front Cell Infect Microbiol ; 12: 803048, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35601095

RESUMO

Visceral leishmaniasis (VL) and post kala-azar dermal leishmaniasis (PKDL) affect most of the poor populations worldwide. The current treatment modalities include liposomal formulation or deoxycholate salt of amphotericin B, which has been associated with various complications and severe side effects. Encouraged from the recent marked antimalarial effects from plant-derived glycosides, in this study, we have exploited a green chemistry-based approach to chemically synthesize a library of diverse glycoside derivatives (Gly1-12) and evaluated their inhibitory efficacy against the AG83 strain of Leishmania donovani. Among the synthesized glycosides, the in vitro inhibitory activity of Glycoside-2 (Gly2) (1.13 µM IC50 value) on L. donovani promastigote demonstrated maximum cytotoxicity with ~94% promastigote death as compared to amphotericin B that was taken as a positive control. The antiproliferative effect of Gly2 on promastigote encouraged us to analyze the structure-activity relationship of Gly2 with Gp63, a zinc metalloprotease that majorly localizes at the surface of the promastigote and has a role in its development and multiplication. The result demonstrated the exceptional binding affinity of Gly2 toward the catalytic domain of Gp63. These data were thereafter validated through cellular thermal shift assay in a physiologically relevant cellular environment. Mechanistically, reduced multiplication of promastigotes on treatment with Gly2 induces the destabilization of redox homeostasis in promastigotes by enhancing reactive oxygen species (ROS), coupled with depolarization of the mitochondrial membrane. Additionally, Gly2 displayed strong lethal effects on infectivity and multiplication of amastigote inside the macrophage in the amastigote-macrophage infection model in vitro as compared to amphotericin B treatment. Gp63 is also known to bestow protection against complement-mediated lysis of parasites. Interestingly, Gly2 treatment enhances the complement-mediated lysis of L. donovani promastigotes in serum physiological conditions. In addition, Gly2 was found to be equally effective against the clinical promastigote forms of PKDL strain (IC50 value of 1.97 µM); hence, it could target both VL and PKDL simultaneously. Taken together, this study reports the serendipitous discovery of Gly2 with potent antileishmanial activity and proves to be a novel chemotherapeutic prototype against VL and PKDL.


Assuntos
Antiprotozoários , Leishmania donovani , Leishmaniose Visceral , Anfotericina B/farmacologia , Antiprotozoários/farmacologia , Antiprotozoários/uso terapêutico , Glicosídeos , Humanos , Leishmaniose Visceral/tratamento farmacológico , Metaloproteases
20.
EMBO Mol Med ; 14(4): e14990, 2022 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-35253392

RESUMO

The heterogeneous response of acute myeloid leukemia (AML) to current anti-leukemic therapies is only partially explained by mutational heterogeneity. We previously identified GPR56 as a surface marker associated with poor outcome across genetic groups, which characterizes two leukemia stem cell (LSC)-enriched compartments with different self-renewal capacities. How these compartments self-renew remained unclear. Here, we show that GPR56+ LSC compartments are promoted in a complex network involving epithelial-to-mesenchymal transition (EMT) regulators besides Rho, Wnt, and Hedgehog (Hh) signaling. Unexpectedly, Wnt pathway inhibition increased the more immature, slowly cycling GPR56+ CD34+ fraction and Hh/EMT gene expression, while Wnt activation caused opposite effects. Our data suggest that the crucial role of GPR56 lies in its ability to co-activate these opposing signals, thus ensuring the constant supply of both LSC subsets. We show that CDK7 inhibitors suppress both LSC-enriched subsets in vivo and synergize with the Bcl-2 inhibitor venetoclax. Our data establish reciprocal transition between LSC compartments as a novel concept underlying the poor outcome in GPR56high AML and propose combined CDK7 and Bcl-2 inhibition as LSC-directed therapy in this disease.


Assuntos
Compostos Bicíclicos Heterocíclicos com Pontes , Quinases Ciclina-Dependentes , Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Sulfonamidas , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Proteína Quinase CDC2/antagonistas & inibidores , Quinases Ciclina-Dependentes/antagonistas & inibidores , Sinergismo Farmacológico , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/uso terapêutico , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/uso terapêutico , Sulfonamidas/farmacologia , Quinase Ativadora de Quinase Dependente de Ciclina
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