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1.
Sci Rep ; 14(1): 10750, 2024 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-38729988

RESUMO

Colorectal cancer (CRC) prevention requires early detection and removal of adenomas. We aimed to develop a computational model for real-time detection and classification of colorectal adenoma. Computationally constrained background based on real-time detection, we propose an improved adaptive lightweight ensemble model for real-time detection and classification of adenomas and other polyps. Firstly, we devised an adaptive lightweight network modification and effective training strategy to diminish the computational requirements for real-time detection. Secondly, by integrating the adaptive lightweight YOLOv4 with the single shot multibox detector network, we established the adaptive small object detection ensemble (ASODE) model, which enhances the precision of detecting target polyps without significantly increasing the model's memory footprint. We conducted simulated training using clinical colonoscopy images and videos to validate the method's performance, extracting features from 1148 polyps and employing a confidence threshold of 0.5 to filter out low-confidence sample predictions. Finally, compared to state-of-the-art models, our ASODE model demonstrated superior performance. In the test set, the sensitivity of images and videos reached 87.96% and 92.31%, respectively. Additionally, the ASODE model achieved an accuracy of 92.70% for adenoma detection with a false positive rate of 8.18%. Training results indicate the effectiveness of our method in classifying small polyps. Our model exhibits remarkable performance in real-time detection of colorectal adenomas, serving as a reliable tool for assisting endoscopists.


Assuntos
Adenoma , Inteligência Artificial , Neoplasias Colorretais , Humanos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/classificação , Adenoma/diagnóstico , Adenoma/classificação , Colonoscopia/métodos , Detecção Precoce de Câncer/métodos , Pólipos do Colo/diagnóstico , Pólipos do Colo/classificação , Pólipos do Colo/patologia , Algoritmos
2.
Int J Cancer ; 155(3): 384-399, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38655783

RESUMO

DNA damage is a prevalent phenomenon in the context of cancer progression. Evidence suggests that DNA damage responses (DDR) are pivotal in overcoming tumor immune evasion. Alternatively, traditional radiotherapy and chemotherapy operate by inducing DNA damage, consequently stimulating the immune system to target tumors. The intricate interplay between signaling pathways involved in DDR and immune activation underscores the significance of considering both factors in developing improved immunotherapies. By delving deeper into the mechanisms underlying immune activation brought on by DNA damage, it becomes possible to identify novel treatment approaches that boost the anticancer immune response while minimizing undesirable side effects. This review explores the mechanisms behind DNA damage-induced antitumor immune responses, the importance of DNA damage in antitumor immunity, and potential therapeutic approaches for cancer immunotherapy targeting DDR. Additionally, we discuss the challenges of combination therapy and strategies for integrating DNA damage-targeting therapies with current cancer immunotherapy. In summary, this review highlights the critical role of DNA damage in tumor immunology, underscoring the potential of DDR inhibitors as promising therapeutic modalities for cancer treatment.


Assuntos
Dano ao DNA , Imunoterapia , Neoplasias , Humanos , Neoplasias/imunologia , Neoplasias/terapia , Imunoterapia/métodos , Animais , Transdução de Sinais , Reparo do DNA
3.
Artigo em Inglês | MEDLINE | ID: mdl-36673982

RESUMO

Breast cancer, with an overall poor clinical prognosis, is one of the most heterogeneous cancers. DNA damage repair (DDR) and epithelial-mesenchymal transition (EMT) have been identified to be associated with cancer's progression. Our study aimed to explore whether genes with both functions play a more crucial role in the prognosis, immune, and therapy response of breast cancer patients. Based on the Cancer Genome Atlas (TCGA) cancer database, we used LASSO regression analysis to identify the six prognostic-related genes with both DDR and EMT functions, including TP63, YWHAZ, BRCA1, CCND2, YWHAG, and HIPK2. Based on the six genes, we defined the risk scores of the patients and reasonably analyzed the overall survival rate between the patients with the different risk scores. We found that overall survival in higher-risk-score patients was lower than in lower-risk-score patients. Subsequently, further GO and KEGG analyses for patients revealed that the levels of immune infiltration varied for patients with high and low risk scores, and the high-risk-score patients had lower immune infiltration's levels and were insensitive to treatment with chemotherapeutic agents. Furthermore, the Gene Expression Omnibus (GEO) database validated our findings. Our data suggest that TP63, YWHAZ, BRCA1, CCND2, YWHAG, and HIPK2 can be potential genetic markers of prognostic assessment, immune infiltration and chemotherapeutic drug sensitivity in breast cancer patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Transição Epitelial-Mesenquimal , Mama , Reparo do DNA , Bases de Dados Factuais , Proteínas de Transporte , Proteínas Serina-Treonina Quinases , Proteínas 14-3-3
4.
Front Cell Dev Biol ; 9: 741074, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604239

RESUMO

Radioresistance conferred by cancer stem cells (CSCs) is the principal cause of the failure of cancer radiotherapy. Eradication of CSCs is a prime therapeutic target and a requirement for effective radiotherapy. Three dimensional (3D) cell-cultured model could mimic the morphology of cells in vivo and induce CSC properties. Emerging evidence suggests that microRNAs (miRNAs) play crucial roles in the regulation of radiosensitivity in cancers. In this study, we aim to investigate the effects of miRNAs on the radiosensitivity of 3D cultured stem-like cells. Using miRNA microarray analysis in 2D and 3D cell culture models, we found that the expression of miR-29b-3p was downregulated in 3D cultured A549 and MCF7 cells compared with monolayer (2D) cells. Clinic data analysis from The Cancer Genome Atlas database exhibited that miR-29b-3p high expression showed significant advantages in lung adenocarcinoma and breast invasive carcinoma patients' prognosis. The subsequent experiments proved that miR-29b-3p overexpression decreased the radioresistance of cells in 3D culture and tumors in vivo through interfering kinetics process of DNA damage repair and inhibiting oncogenes RBL1, PIK3R1, AKT2, and Bcl-2. In addition, miR-29b-3p knockdown enhanced cancer cells invasion and migration capability. MiR-29b-3p overexpression decreased the stemness of 3D cultured cells. In conclusion, our results demonstrate that miR-29b-3p could be a sensitizer of radiation killing in CSC-like cells via inhibiting oncogenes expression. MiR-29b-3p could be a novel therapeutic candidate target for radiotherapy.

5.
J Mol Cell Cardiol ; 124: 45-57, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30291911

RESUMO

BACKGROUND: Adriamycin (ADR) is a powerful chemotherapeutic agent extensively used to treat various human neoplasms. However, its clinical utility is hampered due to severe adverse side effects i.e. cardiotoxicity and heart failure. ADR-induced cardiomyopathy (AIC) has been reported to be caused by myocardial damage and dysfunction through oxidative stress, DNA damage, and inflammatory responses. Nonetheless, the remedies for AIC are even not established. Therefore, we illustrate the role of NAD+/NADH modulation by NAD(P)H quinone oxidoreductase 1 (NQO1) enzymatic action on AIC. METHODS AND RESULTS: AIC was established by intraperitoneal injection of ADR in C57BL/6 wild-type (WT) and NQO1 knockout (NQO1-/-) mice. All Mice were orally administered dunnione (named NQO1 substrate) before and after exposure to ADR. Cardiac biomarker levels in the plasma, cardiac dysfunction, oxidative biomarkers, and mRNA and protein levels of pro-inflammatory mediators were determined compared the cardiac toxicity of each experimental group. All biomarkers of Cardiac damage and oxidative stress, and mRNA levels of pro-inflammatory cytokines including cardiac dysfunction were increased in ADR-treated both WT and NQO1-/- mice. However, this increase was significantly reduced by dunnione in WT, but not in NQO1-/- mice. In addition, a decrease in SIRT1 activity due to a reduction in the NAD+/NADH ratio by PARP-1 hyperactivation was associated with AIC through increased nuclear factor (NF)-κB p65 and p53 acetylation in both WT and NQO1-/- mice. While an elevation in NAD+/NADH ratio via NQO1 enzymatic action using dunnione recovered SIRT1 activity and subsequently deacetylated NF-κB p65 and p53, however not in NQO1-/- mice, thereby attenuating AIC. CONCLUSION: Thus, modulation of NAD+/NADH by NQO1 may be a novel therapeutic approach to prevent chemotherapy-associated heart failure, including AIC.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Doxorrubicina/efeitos adversos , Cardiopatias/etiologia , Cardiopatias/metabolismo , NADH NADPH Oxirredutases/metabolismo , NAD/metabolismo , Animais , Biópsia , Cardiotônicos/farmacologia , Citocinas/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Expressão Gênica , Cardiopatias/diagnóstico , Cardiopatias/fisiopatologia , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Knockout , NADH NADPH Oxirredutases/genética , Naftoquinonas/farmacologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Sirtuína 1/metabolismo
6.
Sci Rep ; 7(1): 3006, 2017 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592850

RESUMO

Acute pancreatitis (AP) is a complicated disease without specific drug therapy. The cofactor nicotinamide adenine dinucleotide (NAD+) is an important regulator of cellular metabolism and homeostasis. However, it remains unclear whether modulation of NAD+ levels has an impact on caerulein-induced AP. Therefore, in this study, we investigated the effect of increased cellular NAD+ levels on caerulein-induced AP. We demonstrated for the first time that the activities and expression of SIRT1 were suppressed by reduction of intracellular NAD+ levels and the p53-microRNA-34a pathway in caerulein-induced AP. Moreover, we confirmed that the increase of cellular NAD+ by NQO1 enzymatic action using the substrate ß-Lapachone suppressed caerulein-induced AP with down-regulating TLR4-mediated inflammasome signalling, and thereby reducing the inflammatory responses and pancreatic cell death. These results suggest that pharmacological stimulation of NQO1 could be a promising therapeutic strategy to protect against pathological tissue damage in AP.


Assuntos
Inflamassomos/metabolismo , NAD/metabolismo , Pancreatite Necrosante Aguda/patologia , Transdução de Sinais , Animais , Ceruletídeo/toxicidade , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , NAD(P)H Desidrogenase (Quinona)/metabolismo , Pancreatite Necrosante Aguda/induzido quimicamente , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo
7.
Biomed Res Int ; 2016: 4048390, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26881219

RESUMO

Cisplatin is a widely used chemotherapeutic agent for the treatment of various tumors. In addition to its antitumor activity, cisplatin affects normal cells and may induce adverse effects such as ototoxicity, nephrotoxicity, and peripheral neuropathy. Various mechanisms such as DNA adduct formation, mitochondrial dysfunction, oxidative stress, and inflammatory responses are closely associated with cisplatin-induced nephrotoxicity; however, the precise mechanism remains unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as a key regulator of cellular energy metabolism and homeostasis. Recent studies have demonstrated associations between disturbance in intracellular NAD(+) levels and clinical progression of various diseases through the production of reactive oxygen species and inflammation. Furthermore, we demonstrated that reduction of the intracellular NAD(+)/NADH ratio is critically involved in cisplatin-induced kidney damage through inflammation and oxidative stress and that increase of the cellular NAD(+)/NADH ratio suppresses cisplatin-induced kidney damage by modulation of potential damage mediators such as oxidative stress and inflammatory responses. In this review, we describe the role of NAD(+) metabolism in cisplatin-induced nephrotoxicity and discuss a potential strategy for the prevention or treatment of cisplatin-induced adverse effects with a particular focus on NAD(+)-dependent cellular pathways.


Assuntos
Cisplatino/efeitos adversos , Neoplasias/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Insuficiência Renal/patologia , Apoptose/efeitos dos fármacos , Cisplatino/uso terapêutico , Dano ao DNA/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , NAD/metabolismo , Neoplasias/complicações , Neoplasias/patologia , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal/induzido quimicamente
8.
Hear Res ; 333: 235-246, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26341473

RESUMO

Ototoxicity is an important issue in patients receiving cisplatin chemotherapy. Numerous studies have demonstrated that cisplatin-induced ototoxicity is related to oxidative stress and DNA damage. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as an important regulator of energy metabolism and cellular homeostasis. Here, we demonstrate that the levels and activities of sirtuin-1 (SIRT1) are suppressed by the reduction of intracellular NAD(+) levels in cisplatin-mediated ototoxicity. We provide evidence that the decreases in SIRT1 activity and expression facilitated by increasing poly(ADP-ribose) polymerase-1 (PARP-1) activation and microRNA-34a levels through cisplatin-mediated p53 activation aggravate the associated ototoxicity. Furthermore, we show that the induction of cellular NAD(+) levels using dunnione, which targets intracellular NQO1, prevents the toxic effects of cisplatin through the regulation of PARP-1 and SIRT1 activity. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological agents could be a promising therapeutic approach for protection from cisplatin-induced ototoxicity.


Assuntos
Cisplatino , Cóclea/efeitos dos fármacos , Perda Auditiva/prevenção & controle , Audição/efeitos dos fármacos , NAD/metabolismo , Naftoquinonas/farmacologia , Substâncias Protetoras/farmacologia , Acetilação , Animais , Cóclea/metabolismo , Cóclea/fisiopatologia , Citoproteção , Modelos Animais de Doenças , Perda Auditiva/induzido quimicamente , Perda Auditiva/metabolismo , Perda Auditiva/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , NAD(P)H Desidrogenase (Quinona)/deficiência , NAD(P)H Desidrogenase (Quinona)/genética , Poli(ADP-Ribose) Polimerase-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo , Fator de Transcrição RelA/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína Supressora de Tumor p53/metabolismo
9.
Biochem Biophys Res Commun ; 467(4): 697-703, 2015 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-26498527

RESUMO

Although cisplatin is a widely used anticancer drug for the treatment of a variety of tumors, its use is critically limited because of adverse effects such as ototoxicity, nephrotoxicity, neuropathy, and gastrointestinal damage. Cisplatin treatment increases oxidative stress biomarkers in the small intestine, which may induce apoptosis of epithelial cells and thereby elicit damage to the small intestine. Nicotinamide adenine dinucleotide (NAD(+)) is a cofactor for various enzymes associated with cellular homeostasis. In the present study, we demonstrated that the hyper-activation of poly(ADP-ribose) polymerase-1 (PARP-1) is closely associated with the depletion of NAD(+) in the small intestine after cisplatin treatment, which results in downregulation of sirtuin1 (SIRT1) activity. Furthermore, a decrease in SIRT1 activity was found to play an important role in cisplatin-mediated small intestinal damage through nuclear factor (NF)-κB p65 activation, facilitated by its acetylation increase. However, use of dunnione as a strong substrate for the NADH:quinone oxidoreductase 1 (NQO1) enzyme led to an increase in intracellular NAD(+) levels and prevented the cisplatin-induced small intestinal damage correlating with the modulation of PARP-1, SIRT1, and NF-κB. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological NQO1 substrates could be a promising therapeutic approach for protecting against cisplatin-induced small intestinal damage.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Intestino Delgado/efeitos dos fármacos , NAD/metabolismo , Naftoquinonas/farmacologia , Animais , Apoptose/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Sirtuína 1/metabolismo , Fator de Transcrição RelA/metabolismo
10.
Hear Res ; 326: 30-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25891352

RESUMO

Ototoxicity is an important issue in patients receiving cisplatin chemotherapy. Numerous studies have demonstrated that several mechanisms, including oxidative stress, DNA damage, and inflammatory responses, are closely associated with cisplatin-induced ototoxicity. Although much attention has been directed at identifying ways to protect the inner ear from cisplatin-induced damage, the precise underlying mechanisms have not yet been elucidated. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as an important regulator of cellular energy metabolism and homeostasis. NAD(+) acts as a cofactor for various enzymes including sirtuins (SIRTs) and poly(ADP-ribose) polymerases (PARPs), and therefore, maintaining adequate NAD(+) levels has therapeutic benefits because of its effect on NAD(+)-dependent enzymes. Recent studies demonstrated that disturbance in intracellular NAD(+) levels is critically involved in cisplatin-induced cochlear damage associated with oxidative stress, DNA damage, and inflammatory responses. In this review, we describe the importance of NAD(+) in cisplatin-induced ototoxicity and discuss potential strategies for the prevention or treatment of cisplatin-induced ototoxicity with a particular focus on NAD(+)-dependent cellular pathways.


Assuntos
Cisplatino/efeitos adversos , Perda Auditiva/induzido quimicamente , Perda Auditiva/prevenção & controle , NAD/metabolismo , Animais , Antineoplásicos/efeitos adversos , Dano ao DNA , Audição/efeitos dos fármacos , Audição/fisiologia , Perda Auditiva/metabolismo , Humanos , Inflamação/induzido quimicamente , Redes e Vias Metabólicas , Modelos Biológicos , Espécies Reativas de Oxigênio/metabolismo
11.
Mol Cells ; 37(3): 234-40, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24642709

RESUMO

Cisplatin is one of the most potent chemotherapy agents. However, its use is limited due to its toxicity in normal tissues, including the kidney and ear. In particular, nephrotoxicity induced by cisplatin is closely associated with oxidative stress and inflammation. Heme oxygenase-1 (HO-1), the rate-limiting enzyme in the heme metabolism, has been implicated in a various cellular processes, such as inflammatory injury and anti-oxidant/oxidant homeostasis. Capsaicin is reported to have therapeutic potential in cisplatin-induced renal failures. However, the mechanisms underlying its protective effects on cisplatin-induced nephrotoxicity remain largely unknown. Herein, we demonstrated that administration of capsaicin ameliorates cisplatin-induced renal dysfunction by assessing the levels of serum creatinine and blood urea nitrogen (BUN) as well as tissue histology. In addition, capsaicin treatment attenuates the expression of inflammatory mediators and oxidative stress markers for renal damage. We also found that capsaicin induces HO-1 expression in kidney tissues and HK-2 cells. Notably, the protective effects of capsaicin were completely abrogated by treatment with either the HO inhibitor ZnPP IX or HO-1 knockdown in HK-2 cells. These results suggest that capsaicin has protective effects against cisplatin-induced renal dysfunction through induction of HO-1 as well as inhibition oxidative stress and inflammation.


Assuntos
Injúria Renal Aguda/enzimologia , Antineoplásicos/efeitos adversos , Capsaicina/farmacologia , Cisplatino/efeitos adversos , Heme Oxigenase-1/genética , Proteínas de Membrana/genética , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/prevenção & controle , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Capsaicina/uso terapêutico , Linhagem Celular , Indução Enzimática/efeitos dos fármacos , Heme Oxigenase-1/metabolismo , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos C57BL , Estresse Oxidativo
12.
Kidney Int ; 85(3): 547-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24025646

RESUMO

Cisplatin is a widely used chemotherapeutic agent for the treatment of various tumors. In addition to its antitumor activity, cisplatin affects normal cells and may induce adverse effects, such as ototoxicity, nephrotoxicity, and neuropathy. Various mechanisms, such as DNA adduct formation, mitochondrial dysfunction, oxidative stress, and inflammatory responses, are critically involved in cisplatin-induced adverse effects. As NAD(+) is a cofactor for various enzymes associated with cellular homeostasis, we studied the effects of increased NAD(+) levels by means of NAD(P)H: quinone oxidoreductase 1 (NQO1) activation using a known pharmacological activator (ß-lapachone) in wild-type and NQO1(-/-) mice on cisplatin-induced renal dysfunction in vivo. The intracellular NAD(+)/NADH ratio in renal tissues was significantly increased in wild-type mice co-treated with cisplatin and ß-lapachone compared with the ratio in mice treated with cisplatin alone. Inflammatory cytokines and biochemical markers for renal damage were significantly attenuated by ß-lapachone co-treatment compared with those in the cisplatin alone group. Notably, the protective effects of ß-lapachone in wild-type mice were completely abrogated in NQO1(-/-) mice. Moreover, ß-lapachone enhanced the tumoricidal action of cisplatin in a xenograft tumor model. Thus, intracellular regulation of NAD(+) levels through NQO1 activation might be a promising therapeutic target for the protection of cisplatin-induced acute kidney injury.


Assuntos
Injúria Renal Aguda/prevenção & controle , Antineoplásicos/toxicidade , Cisplatino/toxicidade , NAD(P)H Desidrogenase (Quinona)/fisiologia , NAD/análise , Injúria Renal Aguda/induzido quimicamente , Animais , Camundongos Endogâmicos C57BL , Naftoquinonas/farmacologia , Sirtuína 1/metabolismo , Fator de Transcrição RelA/metabolismo
13.
Electrolyte Blood Press ; 12(2): 55-65, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25606044

RESUMO

Cisplatin is one of the most widely used and highly effective drug for the treatment of various solid tumors; however, it has dose-dependent side effects on the kidney, cochlear, and nerves. Nephrotoxicity is the most well-known and clinically important toxicity. Numerous studies have demonstrated that several mechanisms, including oxidative stress, DNA damage, and inflammatory responses, are closely associated with cisplatin-induced nephrotoxicity. Even though the establishment of cisplatin-induced nephrotoxicity can be alleviated by diuretics and pre-hydration of patients, the prevalence of cisplatin nephrotoxicity is still high, occurring in approximately one-third of patients who have undergone cisplatin therapy. Therefore it is imperative to develop treatments that will ameliorate cisplatin-nephrotoxicity. In this review, we discuss the mechanisms of cisplatin-induced renal toxicity and the new strategies for protecting the kidneys from the toxic effects without lowering the tumoricidal activity.

14.
J Immunol ; 186(2): 1140-50, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21148032

RESUMO

Dysfunction in immune surveillance during anticancer chemotherapy of patients often causes weakness of the host defense system and a subsequent increase in microbial infections. However, the deterioration of organ-specific function related to microbial challenges in cisplatin-treated patients has not yet been elucidated. In this study, we investigated cisplatin-induced TLR4 expression and its binding to LPS in mouse cochlear tissues and the effect of this interaction on hearing function. Cisplatin increased the transcriptional and translational expression of TLR4 in the cochlear tissues, organ of Corti explants, and HEI-OC1 cells. Furthermore, cisplatin increased the interaction between TLR4 and its microbial ligand LPS, thereby upregulating the production of proinflammatory cytokines, such as TNF-α, IL-1ß, and IL-6, via NF-κB activation. In C57BL/6 mice, the combined injection of cisplatin and LPS caused severe hearing impairment compared with that in the control, cisplatin-alone, or LPS-alone groups, whereas this hearing dysfunction was completely suppressed in both TLR4 mutant and knockout mice. These results suggest that hearing function can be easily damaged by increased TLR expression and microbial infections due to the weakened host defense systems of cancer patients receiving therapy comprising three to six cycles of cisplatin alone or cisplatin combined with other chemotherapeutic agents. Moreover, such damage can occur even though patients may not experience ototoxic levels of cumulative cisplatin concentration.


Assuntos
Antineoplásicos/toxicidade , Cisplatino/toxicidade , Lipopolissacarídeos/metabolismo , Órgão Espiral/efeitos dos fármacos , Órgão Espiral/fisiologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/metabolismo , Animais , Antineoplásicos/administração & dosagem , Linhagem Celular Transformada , Cisplatino/administração & dosagem , Ligantes , Lipopolissacarídeos/fisiologia , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Knockout , Técnicas de Cultura de Órgãos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo , Receptor 4 Toll-Like/deficiência , Receptor 4 Toll-Like/fisiologia
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