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1.
BMC Complement Med Ther ; 24(1): 157, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609946

RESUMO

BACKGROUND: Oral bacterial infections are difficult to treat due to emergence of resistance against antibiotic therapy. Essential oils are considered emerging alternate therapy against bacterial infections and biofilms. We investigated Citrus bergemia flower essential oil against oral pathogens. METHODS: The essential oil was analsyed using Gas Chromatography(GC-MS), in silico investigations, antioxidant, antimicrobial, antibiofilm and antiquorum sensing assays. RESULTS: Gas Chromatography analysis confirmed presence of 17 compounds including 1,6-Octadien-3-ol,3,7-dimethyl, 48.17%), l-limonene (22.03%) and p-menth-1-ol, 8-ol (7.31%) as major components. In silico analysis showed compliance of all tested major components with Lipinski's rule, Bioavailability and antimicrobial activity using PASS (prediction of activity spectrum of substances). Molecular docking with transcriptional regulators 3QP5, 5OE3, 4B2O and 3Q3D revealed strong interaction of all tested compounds except 1,6-Octadien-3-ol,3,7-dimethyl. All tested compounds presented significant inhibition of DPPH (2,2-diphenyl-1-picrylhydrazyl) (IC50 0.65 mg/mL), H2O2 (hydrogen peroxide) (63.5%) and high FRAP (ferrous reducing antioxidant power) value (239.01 µg). In antimicrobial screening a significant activity (MIC 0.125 mg/mL) against Bacillus paramycoides and Bacillus chungangensis was observed. Likewise a strong antibiofilm (52.1 - 69.5%) and anti-QS (quorum sensing) (4-16 mm) activity was recorded in a dose dependent manner. CONCLUSION: It was therefore concluded that C. bergemia essential oil posess strong antioxidant, antimicrobial and antibiofilm activities against tested oral pathogens.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Citrus , Óleos Voláteis , Antioxidantes/farmacologia , Peróxido de Hidrogênio , Simulação de Acoplamento Molecular , Óleos Voláteis/farmacologia , Anti-Infecciosos/farmacologia , Flores
3.
J Clin Tuberc Other Mycobact Dis ; 35: 100433, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38617837

RESUMO

Background: World Health Organization suggests concurrent bedaquiline-delamanid (BDQ-DLM) as part of individualised regimens for eligible patients with pulmonary drug-resistant tuberculosis (DR-TB); however, data for patients with drug-resistant extrapulmonary tuberculosis (EPTB) is extremely limited. This study documents the treatment outcomes and adverse events associated with concurrent BDQ-DLM-based regimens in patients with drug-resistant EPTB at a Médecins Sans Frontières clinic in Mumbai, India. Methods: Retrospective cohort study based on routinely collected programmatic data. Individualised regimens were based on drug-susceptibility testing and previous drug exposure. Drug-resistant EPTB patients initiated on regimens containing concurrent BDQ and DLM from April 2016 to October 2019 were included. Patients who completed treatment were followed up at 12 months. Results: Of 17 patients, median age was 23 years (IQR = 21-30 years) and 12/17 (71 %) were female. Pre-extensively drug-resistant tuberculosis and extensively drug-resistant TB was reported in 13/17 (76.4 %) and 2/17 (11.7 %) patients respectively. Microbiological reports were unavailable for two patients with central nervous system TB. Lymph node TB was the commonest form of EPTB in 9/17 (53 %) of patients. Median duration of treatment was 18.9 months. At least one grade three or four severe adverse event (SAE) was reported by 13/17 (76.4 %) patients. Thirteen (76.4 %) patients had favourable outcomes. None of the patients relapsed or died in the one-year period of post-treatment follow-up. Conclusion: Concurrent BDQ-DLM-based regimens in drug-resistant EPTB were effective and associated with manageable adverse events.

4.
Mol Ther Nucleic Acids ; 35(2): 102177, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38617976

RESUMO

Lung cancer remains a significant global health concern with limited treatment options and poor prognosis, particularly in advanced stages. Small extracellular vesicles such as exosomes, secreted by cancer cells, play a pivotal role in mediating drug resistance in lung cancer. Exosomes have been found to facilitate intercellular communication by transferring various biomolecules between cancer cells and their microenvironment. Additionally, exosomes can transport signaling molecules promoting cancer cell survival and proliferation conferring resistance to chemotherapy. Moreover, exosomes can modulate the tumor microenvironment by inducing phenotypic changes hindering drug response. Understanding the role of exosomes in mediating drug resistance in lung cancer is crucial for developing novel therapeutic strategies and biomarkers to overcome treatment limitations. In this review, we summarize the current knowledge on conventional and emerging drug resistance mechanisms and the involvement of exosomes as well as exosome-mediated factors mediating drug resistance in lung cancer.

5.
Cell Commun Signal ; 22(1): 228, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622735

RESUMO

Cancer is a major public health problem worldwide with more than an estimated 19.3 million new cases in 2020. The occurrence rises dramatically with age, and the overall risk accumulation is combined with the tendency for cellular repair mechanisms to be less effective in older individuals. Conventional cancer treatments, such as radiotherapy, surgery, and chemotherapy, have been used for decades to combat cancer. However, the emergence of novel fields of cancer research has led to the exploration of innovative treatment approaches focused on immunotherapy, epigenetic therapy, targeted therapy, multi-omics, and also multi-target therapy. The hypothesis was based on that drugs designed to act against individual targets cannot usually battle multigenic diseases like cancer. Multi-target therapies, either in combination or sequential order, have been recommended to combat acquired and intrinsic resistance to anti-cancer treatments. Several studies focused on multi-targeting treatments due to their advantages include; overcoming clonal heterogeneity, lower risk of multi-drug resistance (MDR), decreased drug toxicity, and thereby lower side effects. In this study, we'll discuss about multi-target drugs, their benefits in improving cancer treatments, and recent advances in the field of multi-targeted drugs. Also, we will study the research that performed clinical trials using multi-target therapeutic agents for cancer treatment.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Idoso , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos
6.
Open Life Sci ; 19(1): 20220848, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38623585

RESUMO

Bortezomib (BTZ), a proteasome inhibitor, is a promising therapeutic option for multiple myeloma (MM) patients. However, drug resistance often occurs, leading to disease relapse and poor prognosis. In this study, we aimed to identify novel genes associated with drug resistance and investigate their roles in BTZ resistance. Through the screening of 26 genes frequently associated with chemosensitivity or drug resistance, we discovered that KDM4C, a histone demethylase, exhibited increased expression in BTZ-resistant MM cells compared to their sensitive counterparts. Overexpression of KDM4C enhanced the tolerance of a MM cell line to the drug, whereas the knockdown of KDM4C, using shRNA, increased the sensitivity of resistant cells to BTZ treatment. This suggests that KDM4C plays a pivotal role in conferring BTZ resistance. Our study offers fresh insights into BTZ resistance in MM and highlights KDM4C as a potential target for overcoming drug resistance.

7.
Arch Pharm Res ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632167

RESUMO

The molecular chaperone heat shock protein 90 (HSP90) regulates multiple crucial signalling pathways in cancer by driving the maturation of key signalling components, thereby playing a crucial role in tumorigenesis and drug resistance in cancer. Inhibition of HSP90 results in metastable conformational collapse of its client proteins and their proteasomal degradation. Considerable efforts have been devoted to the development of small-molecule inhibitors targeting HSP90, and more than 20 inhibitors have been evaluated in clinical trials for cancer therapy. However, owing to disadvantages such as organ toxicity and drug resistance, only one HSP90 inhibitor has been approved for use in clinical settings. In recent years, HSP90 inhibitors used in combination with other anti-cancer therapies have shown remarkable potential in the treatment of cancer. HSP90 inhibitors work synergistically with various anti-cancer therapies, including chemotherapy, targeted therapy, radiation therapy and immunotherapy. HSP90 inhibitors can improve the pharmacological effects of the above-mentioned therapies and reduce treatment resistance. This review provides an overview of the use of combination therapy with HSP90 inhibitors and other anti-cancer therapies in clinical and preclinical studies reported in the past decade and summarises design strategies and prospects for these combination therapies. Altogether, this review provides a theoretical basis for further research and application of these combination therapies in the treatment of cancer.

8.
Avicenna J Med Biotechnol ; 16(1): 34-39, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38605743

RESUMO

Background: Multi-drug resistance is an important challenge in the chemotherapy of cancer. The role of annexin A5 (ANXA5) in the biology of cancer has been the focus of many studies. Breast Cancer (BC) is frequent cancer in women with high morbidity and mortality rate. The present study aimed to investigate the effects of ANXA5 overexpression on the anti-tumor activity of Epirubicin (EPI) in MCF-7 and MCF-7/ADR cells. Methods: MCF-7 and MCF-7/ADR cells were transfected with the pAdenoVator-CMV-ANXA5-IRES-GFP plasmid or mock plasmid. The overexpression of ANXA5 was evaluated using qPCR. The effects of ANXA5 overexpression and EPI on the cell viability of MCF-7 and MCF-7/ADR cells were measured using an MTT assay. Cell apoptosis was measured by annexin V/7-AAD flow cytometry assay. Results: Following the overexpression of ANXA5, the viability of MCF-7 and MCF-7/ADR was significantly decreased. Furthermore, the overexpression of ANXA5 in MCF-7 cells increased the cytotoxic effects of EPI in all doses and reduced the IC50 of EPI from 17.69 µM to 4.07 µM. Similarly, the overexpression of ANXA5 in MCF7-ADR cells reduced the IC50 of EPI from 27.3 µM to 6.69 µM. ANXA5 overexpression alone or combined with EPI treatment increased the apoptosis of MCF7 and MCF7-ADR cells. Conclusion: The results of the present study demonstrate that ANXA5 overexpression increases the sensitivity of MCF-7 and MCF-7/ADR to EPI, suggesting a possible beneficial role of ANXA5 in the therapy of BC.

9.
Microb Drug Resist ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608246

RESUMO

Integrative and conjugative elements (ICEs) are important vectors of lateral gene transfer and contribute to the evolution of bacterial pathogens. However, studies on the transfer among species and the physiological consequences of ICEs are rare. The objective of this study was to investigate the cross-species transferability of newly identified erm(B)-carried ICE in Streptococcus anginosus San95 and its physiological consequences after transfer. The erm(B)-carried ICE, characterized by a triple serine integrase module, integrated into hsdM genes, thus designated ICESan95_hsdM. Analysis of ICESan95_hsdM revealed 32 additional ICESan95-like ICEs in the available NCBI genome (n = 24) and sequence of clinical isolates (n = 8). Polymerase chain reaction (PCR) was used to evaluate the 467 clinical isolates, of which 84 were positive for core genes (integrase, relaxase, and T4SS genes) of ICESan95_hsdM. Cross-species transfer experiments demonstrated that ICESan95_hsdM could transfer from S. anginosus to different streptococcal and enterococcal recipients. Growth and competitive culture assays showed acquisition of ICESan95_hsdM incurred no fitness cost. Our work discovered a group of ICEs in Streptococci and Enterococci. For the first time, we demonstrated the broad cross-species transferability to different species or genera of ICEs with no fitness cost that enables commensal S. anginosus to deliver antimicrobial resistance genes to other streptococci and enterococci.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38608935

RESUMO

OBJECTIVE: Antiretroviral therapy (ART) has been implemented in Guangxi for a long time, and no reports about HIV drug resistance mutation (DRM) among children and adolescents experiencing virological failure after ART. This study aimed to analyze HIV DRM prevalence, patterns, and influencing factors among children and adolescents experiencing virologic failure after ART in Guangxi. METHODS: We collected samples from a total of 491 HIV-infected individuals under 18 years old experiencing virological failure after ART from 14 cities in Guangxi. Sequencing and DRM analysis were performed based on pol region. Multivariate logistic regression was employed to analysis the influencing factors of DRM. RESULTS: Among these patients, 396 cases were successfully sequenced. Of all, 52.53% exhibited HIV DRM, including NNRTI (48.48%), NRTI (34.85%) and PI (1.01%). NRTI and NNRTI dual-class resistance was prevalent (30.3%). M184V/I and K103N mutations were the common mutations in NRTI and NNRTI respectively. Men gender (aOR=2.1, 95%CI: 1.26-3.50), CRF01_AE subtype (OR=2.50, 95%CI: 1.02-5.88), the primary regimen 3TC+AZT+NVP (OR=10.00, 95%CI: 5.00-25.00), low pre-treatment CD4+ T lymphocytes (<200 cells/mm³) (OR=1.85, 95%CI: 1.00-3.45), and high viral load (> 1000 copies/ml) (OR=4.90, 95%CI: 1.03-23.39) shown higher risk of DRM. CONCLUSION: HIV DRM is pervasive among children and adolescents experiencing virologic failure in Guangxi. Timely HIV DRM monitoring is crucial to mitigate major mutation accumulation and inform effective treatment strategies.

11.
J Pathol ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38613194

RESUMO

Genomic rearrangements of the neurotrophic receptor tyrosine kinase genes (NTRK1, NTRK2, and NTRK3) are the most common mechanism of oncogenic activation for this family of receptors, resulting in sustained cancer cell proliferation. Several targeted therapies have been approved for tumours harbouring NTRK fusions and a new generation of TRK inhibitors has already been developed due to acquired resistance. We established a patient-derived LMNA::NTRK1-rearranged soft-tissue sarcoma cell model ex vivo with an acquired resistance to targeted TRK inhibition. Molecular profiling of the resistant clones revealed an acquired NF2 loss of function mutation that was absent in the parental cell model. Parental cells showed continuous sensitivity to TRK-targeted treatment, whereas the resistant clones were insensitive. Furthermore, resistant clones showed upregulation of the MAPK and mTOR/AKT pathways in the gene expression based on RNA sequencing data and increased sensitivity to MEK and mTOR inhibitor therapy. Drug synergy was seen using trametinib and rapamycin in combination with entrectinib. Medium-throughput drug screening further identified small compounds as potential drug candidates to overcome resistance as monotherapy or in combination with entrectinib. In summary, we developed a comprehensive model of drug resistance in an LMNA::NTRK1-rearranged soft-tissue sarcoma and have broadened the understanding of acquired drug resistance to targeted TRK therapy. Furthermore, we identified drug combinations and small compounds to overcome acquired drug resistance and potentially guide patient care in a functional precision oncology setting. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

12.
Proc Natl Acad Sci U S A ; 121(15): e2316662121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557187

RESUMO

Drug resistance in HIV type 1 (HIV-1) is a pervasive problem that affects the lives of millions of people worldwide. Although records of drug-resistant mutations (DRMs) have been extensively tabulated within public repositories, our understanding of the evolutionary kinetics of DRMs and how they evolve together remains limited. Epistasis, the interaction between a DRM and other residues in HIV-1 protein sequences, is key to the temporal evolution of drug resistance. We use a Potts sequence-covariation statistical-energy model of HIV-1 protein fitness under drug selection pressure, which captures epistatic interactions between all positions, combined with kinetic Monte-Carlo simulations of sequence evolutionary trajectories, to explore the acquisition of DRMs as they arise in an ensemble of drug-naive patient protein sequences. We follow the time course of 52 DRMs in the enzymes protease, RT, and integrase, the primary targets of antiretroviral therapy. The rates at which DRMs emerge are highly correlated with their observed acquisition rates reported in the literature when drug pressure is applied. This result highlights the central role of epistasis in determining the kinetics governing DRM emergence. Whereas rapidly acquired DRMs begin to accumulate as soon as drug pressure is applied, slowly acquired DRMs are contingent on accessory mutations that appear only after prolonged drug pressure. We provide a foundation for using computational methods to determine the temporal evolution of drug resistance using Potts statistical potentials, which can be used to gain mechanistic insights into drug resistance pathways in HIV-1 and other infectious agents.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , HIV-1/genética , Farmacorresistência Viral/genética , Genótipo , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , Mutação , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico
13.
Crit Rev Oncol Hematol ; : 104362, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38614267

RESUMO

In the tumor microenvironment (TME), myeloid cells play a pivotal role. Myeloid-derived immunosuppressive cells, including tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs), are central components in shaping the immunosuppressive milieu of the tumor. Within the TME, a majority of TAMs assume an M2 phenotype, characterized by their pro-tumoral activity. These cells promote tumor cell growth, angiogenesis, invasion, and migration. In contrast, M1 macrophages, under appropriate activation conditions, exhibit cytotoxic capabilities against cancer cells. However, an excessive M1 response may lead to pro-tumoral inflammation. As a result, myeloid cells have emerged as crucial targets in cancer therapy. This review concentrates on gastrointestinal tumors, detailing methods for targeting macrophages to enhance tumor radiotherapy and immunotherapy sensitivity. We specifically delve into monocytes and tumor-associated macrophages' various functions, establishing an immunosuppressive microenvironment, promoting tumorigenic inflammation, and fostering neovascularization and stromal remodeling. Additionally, we examine combination therapeutic strategies.

14.
Int J Mol Sci ; 25(7)2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38612471

RESUMO

Acquired immunodeficiency syndrome (AIDS) is an enormous global health threat stemming from human immunodeficiency virus (HIV-1) infection. Up to now, the tremendous advances in combination antiretroviral therapy (cART) have shifted HIV-1 infection from a fatal illness into a manageable chronic disorder. However, the presence of latent reservoirs, the multifaceted nature of HIV-1, drug resistance, severe off-target effects, poor adherence, and high cost restrict the efficacy of current cART targeting the distinct stages of the virus life cycle. Therefore, there is an unmet need for the discovery of new therapeutics that not only bypass the limitations of the current therapy but also protect the body's health at the same time. The main goal for complete HIV-1 eradication is purging latently infected cells from patients' bodies. A potential strategy called "lock-in and apoptosis" targets the budding phase of the life cycle of the virus and leads to susceptibility to apoptosis of HIV-1 infected cells for the elimination of HIV-1 reservoirs and, ultimately, for complete eradication. The current work intends to present the main advantages and disadvantages of United States Food and Drug Administration (FDA)-approved anti-HIV-1 drugs as well as plausible strategies for the design and development of more anti-HIV-1 compounds with better potency, favorable pharmacokinetic profiles, and improved safety issues.


Assuntos
Síndrome de Imunodeficiência Adquirida , HIV-1 , Estados Unidos , Humanos , United States Food and Drug Administration , Apoptose , Divisão Celular
15.
Int J Mol Sci ; 25(7)2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38612785

RESUMO

Trueperella pyogenes can cause various infections in the organs and tissues of different livestock (including pigs, cows, goats, and sheep), including mastitis, endometritis, pneumonia, or abscesses. Moreover, diseases induced by T. pyogenes cause significant economic losses in animal husbandry. In recent large-scale investigations, T. pyogenes has been identified as one of the main pathogens causing endometritis in lactating cows. However, the main treatment for the above-mentioned diseases is still currently antibiotic therapy. Understanding the impact of endometritis associated with T. pyogenes on the fertility of cows can help optimize antibiotic treatment for uterine diseases, thereby strategically concentrating the use of antimicrobials on the most severe cases. Therefore, it is particularly important to continuously monitor the prevalence of T. pyogenes and test its drug resistance. This study compared the uterine microbiota of healthy cows and endometritis cows in different cattle farms, investigated the prevalence of T. pyogenes, evaluated the genetic characteristics and population structure of isolated strains, and determined the virulence genes and drug resistance characteristics of T. pyogenes. An amount of 186 dairy cows were involved in this study and 23 T. pyogenes strains were isolated and identified from the uterine lavage fluid of dairy cows with or without endometritis.


Assuntos
Endometrite , Feminino , Humanos , Bovinos , Animais , Ovinos , Suínos , Endometrite/veterinária , Lactação , Virulência/genética , Genótipo , Útero , Cabras
16.
Int J Mol Sci ; 25(7)2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38612882

RESUMO

Non-coding RNAs have been described as crucial regulators of gene expression and guards of cellular homeostasis. Some recent papers focused on vault RNAs, one of the classes of non-coding RNA, and their role in cell proliferation, tumorigenesis, apoptosis, cancer response to therapy, and autophagy, which makes them potential therapy targets in oncology. In the human genome, four vault RNA paralogues can be distinguished. They are associated with vault complexes, considered the largest ribonucleoprotein complexes. The protein part of these complexes consists of a major vault protein (MVP) and two minor vault proteins (vPARP and TEP1). The name of the complex, as well as vault RNA, comes from the hollow barrel-shaped structure that resembles a vault. Their sequence and structure are highly evolutionarily conserved and show many similarities in comparison with different species, but vault RNAs have various roles. Vaults were discovered in 1986, and their functions remained unclear for many years. Although not much is known about their contribution to cell metabolism, it has become clear that vault RNAs are involved in various processes and pathways associated with cancer progression and modulating cell functioning in normal and pathological stages. In this review, we discuss known functions of human vault RNAs in the context of cellular metabolism, emphasizing processes related to cancer and cancer therapy efficacy.


Assuntos
Carcinogênese , Genoma Humano , Humanos , Transformação Celular Neoplásica , Apoptose , RNA/genética
17.
J Nepal Health Res Counc ; 21(3): 353-365, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38615204

RESUMO

BACKGROUND: This systematic review aimed to determine the antimicrobial resistance pattern of the extended-spectrum ß-lactamases producing Escherichia coli (ESBL-EC) in urine samples in Nepal. METHODS: Systematic literature review was conducted to locate all articles reporting ESBL-EC in urine samples published between January 2012 to December 2022. The Egger's weighted regression analysis was done to assess the publication bias. A random-effects model was used to calculate the pooled prevalence and corresponding 95% confidence interval due to significant between-study heterogeneity. The strength of correlation between multidrug resistance and ESBL production in E.coli strains was determined using Pearson's correlation coefficient. The data were analyzed using R-language 4.2.2. software. RESULTS: The combined prevalence of E.coli in urine samples was found to be 14 % (95% CI, 11-18), while the overall pooled prevalence of ESBL E.coli and MDR E.coli were 30% (95% CI, 20-42) and 70% (95% CI, 38-90) respectively. A strong positive correlation of 0.99 (95% CI, 0.89-1.0) was found between ESBL production and MDR among E.coli isolates. Imipenem was the drug of choice against ESBL-E.coli in urine specimens. CONCLUSIONS: Our analyses showed the overall ESBL-EC and MDR-EC burden in Nepal is considerably high. Likewise, the study also infers an increasing trend of antibiotic resistance pattern of ESBL-EC in urine samples.


Assuntos
Escherichia coli , Imipenem , Humanos , Nepal/epidemiologia , Resistência Microbiana a Medicamentos , Idioma
18.
Artigo em Inglês | MEDLINE | ID: mdl-38616741

RESUMO

BACKGROUND: Breast cancer remains a leading cause of cancer-related deaths among women, primarily attributed to the formidable challenge of multidrug resistance, often driven by the overexpression of the ABCB1 gene. OBJECTIVE: This study aimed to assess the synergistic effects of siRNA, doxorubicin, and vinorelbine on ABCB1 gene expression and cell viability in doxorubicin-resistant MCF-7/ADR breast cancer cells, with siRNA targeting ABCB1 to reduce its expression and doxorubicin/ vinorelbine to eradicate cancer cells. METHODS: Our methodology involved culturing MCF-7 and MCF-7/ADR cells in standard cell culture conditions. The synthesized siRNA sequences transfected cells with siRNA at final concentrations of 10, 20, and 30 nM and assessed cell viability using the MTT assay was performed. Real-time PCR was employed to quantify ABCB1 mRNA expression levels. RESULTS: Results indicated that MCF-7/ADR cells exhibited substantial resistance to vinorelbine and doxorubicin compared to MCF-7 cells, displaying resistance at 12.50 µM and 25.00 µM for vinorelbine and 6.25 µM and 25.00 µM for doxorubicin. Remarkably, siRNA treatment effectively reversed drug resistance in MCF-7/ADR cells across all concentrations of vinorelbine and doxorubicin tested. When combined, siRNA, doxorubicin, and vinorelbine yielded a significantly greater reduction in cell viability compared to individual drug treatments, particularly at a 20 µM siRNA concentration. This combination therapy also significantly suppressed ABCB1 gene expression by a factor of 41.48 in MCF-7 cells relative to MCF-7/ADR cells. CONCLUSION: these findings suggest that combining siRNA, doxorubicin, and vinorelbine holds promise as a therapeutic strategy to overcome ABCB1-mediated multidrug resistance in breast cancer. Further investigations and clinical trials are warranted to evaluate its clinical efficacy rigorously.

19.
Immunology ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618976

RESUMO

Despite progress in cancer immunotherapy, ovarian cancer (OC) prognosis continues to be disappointing. Recent studies have shed light on how not just tumour cells, but also the complex tumour microenvironment, contribute to this unfavourable outcome of OC immunotherapy. The complexities of the immune microenvironment categorize OC as a 'cold tumour'. Nonetheless, understanding the precise mechanisms through which the microenvironment influences the effectiveness of OC immunotherapy remains an ongoing scientific endeavour. This review primarily aims to dissect the inherent characteristics and behaviours of diverse cells within the immune microenvironment, along with an exploration into its reprogramming and metabolic changes. It is expected that these insights will elucidate the operational dynamics of the immune microenvironment in OC and lay a theoretical groundwork for improving the efficacy of immunotherapy in OC management.

20.
Antimicrob Agents Chemother ; : e0011024, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619252

RESUMO

Ocular herpes simplex virus 1 (HSV-1) infections can lead to visual impairment. Long-term acyclovir (ACV) prophylaxis reduces the frequency of recurrences but is associated with drug resistance. Novel therapies are needed to treat drug-resistant HSV-1 infections. Here, we describe the effects of trifluridine (TFT) in combination with ACV or ganciclovir (GCV) on HSV-1 replication and drug-resistance emergence. Wild-type HSV-1 was grown under increasing doses of one antiviral (ACV, GCV, or TFT) or combinations thereof (ACV + TFT or GCV + TFT). Virus cultures were analyzed by Sanger sequencing and deep sequencing of the UL23 [thymidine kinase (TK)] and UL30 [DNA polymerase (DP)] genes. The phenotypes of novel mutations were determined by cytopathic effect reduction assays. TFT showed overall additive anti-HSV-1 activity with ACV and GCV. Five passages under ACV, GCV, or TFT drug pressure gave rise to resistance mutations, primarily in the TK. ACV + TFT and GCV + TFT combinatory pressure induced mutations in the TK and DP. The DP mutations were mainly located in terminal regions, outside segments that typically carry resistance mutations. TK mutations (R163H, A167T, and M231I) conferring resistance to all three nucleoside analogs (ACV, TFT, and GCV) emerged under ACV, TFT, ACV + TFT pressure and under GCV + TFT pressure initiated from suboptimal drug concentrations. However, higher doses of GCV and TFT prevented drug resistance in the resistance selection experiments. In summary, we identified novel mutations conferring resistance to nucleoside analogs, including TFT, and proposed that GCV + TFT combination therapy may be an effective strategy to prevent the development of drug resistance.

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