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1.
Respirol Case Rep ; 11(8): e01195, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37497338

RESUMO

Mediastinal pancreatic pseudocysts are rare complications of pancreatitis associated with alcohol consumption. Here, we report a case of mediastinal pancreatic pseudocyst. A 61-year-old Japanese woman presented to our hospital with epigastric pain and dyspnea. A chest radiograph revealed right-sided massive pleural effusion. Thoracentesis retrieved black pleural fluid with remarkably high fluid amylase levels were. Thoracic computed tomography (CT) after drainage revealed encapsulated fluid. Magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP) were performed because abdominal CT and ultrasonography did not reveal any pancreatic problems. MRCP showed cystic masses and pancreatic tail cysts extending to the stomach and lower oesophagus. ERCP confirmed leakage of contrast medium from the pancreatic tail into the retroperitoneum. We diagnosed the patient with a pancreatic pseudocyst extending to the mediastinum. A mediastinal pancreatic pseudocyst should be considered a differential diagnosis in patients with black pleural fluid with a high amylase level.

2.
BMC Infect Dis ; 23(1): 285, 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37142952

RESUMO

BACKGROUND: Vogesella species are common aquatic Gram-negative rods that were first reported in 1997. Vogesella urethralis bacterium was first isolated from human urine in 2020. Only two cases of disease caused by Vogesella species have been reported with no case of Vogesella urethralis-caused disease being reported as yet. Herein, we report a case of aspiration pneumonia and bacteremia caused by Vogesella urethralis. CASE PRESENTATION: An 82-year-old male patient was admitted with dyspnea, increased sputum production, and hypoxia. Gram-negative rods were isolated from the blood and sputum cultures of the patient. He was diagnosed with aspiration pneumonia and bacteremia. Initially, Vogesella urethralis was wrongly identified as Comamonas testosteroni based on fully automated susceptibility testing; however, additional 16S rRNA gene sequencing identified the causative as Vogesella urethralis. The patient was treated with piperacillin and tazobactam. Unfortunately, he developed aspiration pneumonia again and died during hospitalization. CONCLUSIONS: Since no database exists for rare bacteria in traditional clinical microbiology laboratories, 16S rRNA gene sequence analysis is useful. We report the first case of Vogesella urethralis-induced aspiration pneumonia and bacteremia.


Assuntos
Bacteriemia , Betaproteobacteria , Pneumonia Aspirativa , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , RNA Ribossômico 16S/genética , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/etiologia , Bactérias Aeróbias , Pneumonia Aspirativa/diagnóstico , Pneumonia Aspirativa/tratamento farmacológico , Pneumonia Aspirativa/etiologia
4.
Intern Med ; 60(19): 3081-3086, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34602522

RESUMO

Objective This study aimed to elucidate the effects of early macrolide administration on genetically confirmed pertussis-induced cough in adolescents and adults. Methods This single-center, retrospective cohort study examined the effects of the early administration of macrolides and antitussive agents on cough secondary to pertussis. We divided the patients into two groups based on the median duration from the beginning of the cough to the initiation of macrolide administration: early macrolide administration group (EMAG) and non-early macrolide administration group (NEMAG). The clinical improvement of cough was defined as maintaining a cough awareness score of ≤3 points for 3 consecutive days. Patients The medical records of 40 patients diagnosed with pertussis (≥12 years old) who were able to maintain a cough diary and received no other antibiotics aside from macrolides were included in the study. A diagnosis of pertussis was made using the loop-mediated isothermal amplification (LAMP) test. Results The EMAG (24 patients) showed a significantly shorter total cough period than the NEMAG [16 patients; 20.0 (95% confidence interval (CI), 16-28) vs. 30.5 (95% CI, 27-40) days; log-rank test, p=0.002]. There was no significant difference in the post-administration cough periods between the EMAG and NEMAG [11.0 (95% CI, 7-19) vs. 13.0 (95% CI, 5-23) days; log-rank test, p=0.232]. Antitussive agents did not affect the cough. Conclusion The early administration of macrolides, but not antitussive agents, is effective for treating pertussis. Therefore, macrolides should be administered as soon as possible for this disease.


Assuntos
Coqueluche , Adolescente , Adulto , Antibacterianos/uso terapêutico , Bordetella pertussis , Criança , Tosse/tratamento farmacológico , Humanos , Macrolídeos , Técnicas de Diagnóstico Molecular , Técnicas de Amplificação de Ácido Nucleico , Estudos Retrospectivos , Coqueluche/tratamento farmacológico , Coqueluche/epidemiologia
5.
J Med Case Rep ; 15(1): 178, 2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33865452

RESUMO

BACKGROUND: Sarcoidosis is pathologically characterized by the formation of non-necrotizing epithelioid cell granulomas. However, pathological findings of patients with sarcoidosis have rarely revealed necrosis. We report here on a patient with sarcoidosis which needed to be distinguished from infectious disease because of marked necrosis in the lymph nodes. CASE PRESENTATION: A 46-year-old Japanese woman was referred to our hospital due to a dry cough and appetite loss. A chest X-ray and computed tomography revealed markedly enlarged mediastinal and hilar lymph nodes and hepatosplenomegaly. Surgical biopsy of these lymph nodes was performed in order to make a diagnosis. Pathological findings revealed epithelioid cell granuloma with marked necrosis that suggested infectious etiology such as mycobacterial and fungal infections. In addition to the pathological findings, immunoglobulin A (IgA) antibody for Mycobacterium avium complex (MAC), enlargement of lymph nodes and hepatosplenomegaly indicated disseminated MAC, while sarcoidosis was considered as another important differential diagnosis according to elevated angiotensin-converting enzyme, soluble interleukin-2 receptor and uveitis. While waiting for the results of the cultures of acid-fast bacilli, the symptoms of cough and consumption had worsened, and initiation of therapy was required before the confirmed diagnosis. The therapy for MAC was initiated because it was feared that immunosuppressive therapy containing corticosteroid for sarcoidosis could worsen the patient's condition if MAC infection was the main etiology. However, the treatment for MAC was not effective, and it was clarified that no acid-fast bacilli were cultured in the liquid culture medium, so the diagnosis was corrected to sarcoidosis after reconsideration of clinical and pathological findings. Prednisolone (30 mg/day) was administered orally, and the patient's symptoms and radiological findings improved. CONCLUSION: Sarcoidosis must be considered even if pathological findings reveal marked necrosis, because rare cases of sarcoidosis exhibit extensive necrosis in lymph nodes. It is extremely important to carefully examine the clinical and pathological findings through discussion with the examining pathologist to reach the correct diagnosis.


Assuntos
Granuloma/patologia , Linfonodos/patologia , Linfadenopatia/diagnóstico por imagem , Necrose/patologia , Sarcoidose/patologia , Biópsia , Feminino , Granuloma/diagnóstico por imagem , Hepatomegalia/diagnóstico por imagem , Humanos , Japão , Linfonodos/diagnóstico por imagem , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Sarcoidose/diagnóstico , Sarcoidose/tratamento farmacológico , Esplenomegalia/diagnóstico por imagem , Tomografia Computadorizada por Raios X
6.
BMJ Case Rep ; 14(4)2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33906872

RESUMO

This report concerns a patient with skeletal muscle metastases due to lung adenocarcinoma harbouring an echinoderm microtubule-associated protein-like-4 (EML4)-anaplastic lymphoma kinase (ALK) rearrangement, who was successfully treated with lorlatinib after resistance to alectinib. A right lower lobectomy based on a diagnosis of lung adenocarcinoma was performed on a 77-year-old Japanese woman. After 7 months of surgical resection, a mass in the right calf was observed. A fine-needle aspiration biopsy from the mass was performed and the mass was diagnosed as metastatic adenocarcinoma harbouring EML4-ALK rearrangement. Alectinib was administered for 10 months. Then, administration of lorlatinib, an ALK tyrosine kinase inhibitor classified as third generation, was initiated after resistance to treatment with alectinib. After starting treatment with lorlatinib, the gastrocnemius tumour diminished and has maintained a stable condition. Our case suggests that EML4-ALK positive lung adenocarcinoma is treatable with lorlatinib after resistance to treatment with alectinib.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Adenocarcinoma de Pulmão/tratamento farmacológico , Adenocarcinoma de Pulmão/genética , Idoso , Aminopiridinas , Carbazóis , Feminino , Humanos , Lactamas , Lactamas Macrocíclicas , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Músculo Esquelético , Proteínas de Fusão Oncogênica/genética , Piperidinas , Inibidores de Proteínas Quinases/uso terapêutico , Pirazóis
7.
J Transl Med ; 19(1): 92, 2021 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-33639962

RESUMO

BACKGROUND: Regimens combining pemetrexed (PEM) and immune checkpoint inhibitors (ICIs) targeting programmed cell death-1 (PD-1) or programmed death-ligand 1 (PD-L1) are widely used for the treatment of advanced non-squamous non-small-cell lung cancer (NSq-NSCLC). Recently, PEM was shown to induce immunogenic cell death (ICD) and to enhance immune-regulatory genes. Some patients demonstrate an extremely long-term response to PEM. It is possible that the continued response in these patients is dependent on not only the pharmacological induction of cytotoxic cell death but also antitumor immunity. However, factors that can predict outcomes associated with long-term PEM administration using blood test results have not yet been elucidated. We investigated the clinical characteristics and predictive factors in patients with advanced NSq-NSCLC who underwent long-term PEM maintenance therapy. METHODS: In total, 504 patients with advanced NSq-NSCLC who received PEM combination therapy/monotherapy (n = 414) or paclitaxel (PTX) combination therapy (n = 90) between January 2010 and November 2019 were recruited; 381 patients were retained for the final analysis. Patients treated with PEM (n = 301) were divided into subgroups according to the total cycles of PEM (≥ 17 [n = 25] for the long-term administration group and ≤ 16 [n = 276] for the intermediate/short-term group) and compared with another population (n = 80) treated with PTX combination regimen. We investigated clinical features and predictive biomarkers, focusing on immune-regulatory factors, absolute lymphocyte count (ALC), neutrophil-to-lymphocyte ratio (NLR), and PD-1 and PD-L1 expression, to predict long-term response to PEM. RESULTS: The long-term PEM administration group exhibited a higher ALC and a lower NLR than the shorter-term group did. Both these markers displayed greater association with progression-free survival and overall survival in the PEM combination therapy group than in the PTX combination therapy group. Increased PD-1 lymphocytes were associated with the long-term PEM response group, as PD-L1 expression in tumors was associated with a high incidence of immune-related adverse effects following ICI administration. CONCLUSIONS: ALC, NLR, and PD-1 expression are PEM-mediated predictive biomarkers that are indirectly related to tumor immunity and can provide useful predictive information on the long-term response to PEM in patients with NSq-NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Contagem de Linfócitos , Linfócitos , Pemetrexede/uso terapêutico
8.
Intern Med ; 58(22): 3283-3287, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31735738

RESUMO

The anti-programmed cell death-1 protein monoclonal antibody, pembrolizumab is an immune checkpoint inhibitor. While it improves the prognoses of patients with advanced non-small-cell lung cancer, it has been reported to induce various kinds of immune-related adverse events, including hepatotoxicity. Despite the frequency of hepatotoxicity, there is only limited information available regarding the pathophysiology and treatment. We herein report a 48-year-old man with lung adenocarcinoma who was treated with pembrolizumab and developed cholestatic liver injury. In this case, the importance of evaluating the histology of hepatotoxicity and the effectiveness of ursodeoxycholic acid for cholestatic liver injury is indicated.


Assuntos
Adenocarcinoma de Pulmão/tratamento farmacológico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/uso terapêutico , Colestase/induzido quimicamente , Neoplasias Pulmonares/tratamento farmacológico , Colestase/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Ácido Ursodesoxicólico/uso terapêutico
9.
Respir Physiol Neurobiol ; 262: 20-25, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30660859

RESUMO

Pulmonary hypertension (PH) due to lung diseases is classified as group 3 by the Dana Point classification. Given the basic pathophysiological conditions of group 3 lung diseases and the previously well-known concept of hypercapnic pulmonary vasoconstriction, chronic hypercapnia besides alveolar hypoxia might be another causative factor to increase mean pulmonary arterial pressure (PAm). Two hundred twenty-five subjects with chronic pulmonary diseases were assessed by a right heart catheterization and blood gas parameters. The subjects were classified into the following 4 groups: Hypercapnic Hypoxia (HCHX), Hypercapnic Normoxia (HCnx), Normocapnic Hypoxia (ncHX), and Normocapnic Normoxia (ncnx). Compared with ncnx, the HCHX, HCnx and ncHX groups all showed significantly higher PAm and met the criteria of borderline PH. Multiple regression analysis showed that PaCO2, as well as SaO2, was an independent variable for PAm. Given the poor prognosis with borderline PH, the elimination of excess pulmonary carbon dioxide in hypercapnia could be a considerable treatment strategy in chronic pulmonary disease.


Assuntos
Hipercapnia/fisiopatologia , Hipertensão Pulmonar/fisiopatologia , Adolescente , Adulto , Idoso , Pressão Arterial , Gasometria , Doença Crônica , Feminino , Humanos , Hidrocarbonetos Clorados/metabolismo , Masculino , Pessoa de Meia-Idade , Oxigênio/metabolismo , Estudos Retrospectivos , Adulto Jovem
10.
Respirol Case Rep ; 6(9): e00379, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30386622

RESUMO

A 69-year-old man was admitted to our hospital with acute dyspnoea, which developed after using a wood-preserving agent in an enclosed space. Burn injuries were evident on his face, neck, chest, and both upper arms. Bronchoalveolar lavage was carried out. The collected fluid resembled wood preservative. Subsequently, it was established that kerosene was a major component of the wood preservative. A diagnosis of hydrocarbon pneumonitis was established. The patient's respiratory and general findings improved with intensive care, which included mechanical ventilation. Corticosteroid was not required to aid his recovery. Aspiration and/or inhalation of hydrocarbon compounds, such as kerosene, turpentine, and gasoline, can cause acute and fatal pneumonitis. In managing cases of hydrocarbon pneumonitis, a prompt diagnosis and appropriate supportive care are important to achieve a good outcome.

12.
Respir Investig ; 56(3): 238-242, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29773295

RESUMO

BACKGROUND: It is well known that ultrasound-guided needle-aspiration (USGNA) for intrapulmonary subpleural lesion in contact with the pleura is useful and safe, and its diagnostic yield is high. However, reports concerned with the analyses of cases with intrapulmonary subpleural lesion which could not be diagnosed using USGNA are limited. The objective of this study is to clarify the radiological properties of subpleural primary lung cancer which obstruct diagnosis by USGNA. METHODS: The consecutive cases with subpleural primary lung cancer whose radiological properties could be confirmed by thoracic computed tomography (CT) without contrast enhancement (CE), and examined by USGNA at our hospital between January 1999 and December 2014 have been analyzed. All cases were given pathological diagnoses of primary lung cancer. The diagnostic yield by USGNA was calculated, and the properties of the lesions of the subjects were analyzed by means of thoracic CT without CE images and pathological findings. RESULTS: 87 consecutive cases (41-86 year olds, 75 males, 12 females) were analyzed. The overall diagnostic yield by USGNA was 86.2%. There was no statistically significant difference regarding the diagnostic yield concerning radiological properties such as cavities, small airspaces and low density areas in the lesions and their sizes. However, the diagnostic yield for the cases with squamous cell carcinoma was statistically significantly low (p=0.02). CONCLUSION: Although the diagnostic yield of USGNA is not distorted by the radiological properties of lesions, it is statistically significantly low in cases with squamous cell carcinoma.


Assuntos
Biópsia por Agulha Fina , Biópsia Guiada por Imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade
14.
Respirol Case Rep ; 4(6): e00202, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28031837

RESUMO

Although both lung cancer and pulmonary tuberculosis (TB) commonly occur in clinical practice, little attention has been paid to their coexistence. A 62-year-old female was admitted with acute dyspnoea secondary to cardiac tamponade. During her admission, a mass lesion harbouring air bronchograms in the right upper lobe rapidly increased in size. Surgical lung, pericardial, and pleural specimens yielded TB from a nodule in the right upper lobe and lung adenocarcinoma from the pericardium and pleura. Anti-tuberculous therapy was administered and gefitinib was subsequently started after the positive identification of epidermal growth factor receptor (EGFR) mutation (exon 19 deletion). The patient's general condition gradually improved with the anti-tuberculous and the EGFR-tyrosine kinase inhibitor (EGFR-TKI) treatment. Dual pathology is important to consider in patients with atypical radiological appearances. In those with proven EGFR mutation positive for lung cancer and pulmonary TB, sequential anti-tuberculous medication followed by EGFR-TKI treatment is advised.

16.
Respir Investig ; 53(3): 98-103, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25951095

RESUMO

BACKGROUND: The usefulness of ultrasound-guided needle aspiration for subpleural lesions has been reported. However, no reports have evaluated its usefulness and safety in patients with respiratory comorbidities such as chronic obstructive pulmonary disease (COPD) and interstitial pneumonia (IP), which can increase the risk of iatrogenic pneumothorax. In this study, we evaluated the influence of chronic respiratory diseases (CRDs) on the usefulness and safety of ultrasound-guided needle aspiration for subpleural lesions. METHODS: Between January 2000 and September 2011, we examined 144 patients with intrapulmonary subpleural lesions. We retrospectively reviewed clinical data, including lesion size on thoracic computed tomography (CT), ultrasound findings, pathological findings obtained by ultrasound-guided needle aspiration, final diagnosis, and complications. RESULTS: A positive definitive diagnosis was obtained in 74.3% of all 144 patients; 84.7% patients with malignant diseases, including lung cancer; and 26.9% patients with benign diseases. Of the 144 patients, 64 belonged to the CRD group and 80 to the non-CRD group. The former included 31 patients with COPD, six with emphysematous changes on thoracic CT, 17 with IP, and 10 with other diseases. The positive rate of diagnosis for malignant diseases was 84.7% in the CRD group, which was the same as that in the non-CRD group. With regard to complications related to ultrasound-guided aspiration, there were only two cases of pneumothorax in the CRD group and one in the non-CRD group. CONCLUSION: Ultrasound-guided aspiration is safe and useful for subpleural lesions, particularly malignant lesions, even in patients with respiratory comorbidities such as COPD and IP.


Assuntos
Biópsia por Agulha Fina , Biópsia Guiada por Imagem , Doenças Pulmonares Intersticiais/epidemiologia , Pneumopatias/diagnóstico por imagem , Pneumopatias/patologia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença Crônica , Comorbidade , Feminino , Humanos , Doença Iatrogênica , Pneumopatias/epidemiologia , Neoplasias Pulmonares/epidemiologia , Masculino , Pessoa de Meia-Idade , Pneumotórax , Estudos Retrospectivos , Risco , Segurança , Ultrassonografia , Adulto Jovem
19.
Am J Physiol Lung Cell Mol Physiol ; 306(11): L996-L1005, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24705719

RESUMO

Upregulation of the erythropoietin (EPO)/EPO receptor (EPOR) system plays a protective role against chronic hypoxia-induced pulmonary hypertension (hypoxic PH) through enhancement of endothelial nitric oxide (NO)-mediated signaling. Genistein (Gen), a phytoestrogen, is considered to ameliorate NO-mediated signaling. We hypothesized that Gen attenuates and prevents hypoxic PH. In vivo, Sprague-Dawley rats raised in a hypobaric chamber were treated with Gen (60 mkg/kg) for 21 days. Pulmonary hemodynamics and vascular remodeling were ameliorated in Gen-treated hypoxic PH rats. Gen also restored cGMP levels and phosphorylated endothelial NO synthase (p-eNOS) at Ser(1177) and p-Akt at Ser(473) expression in the lungs. Additionally, Gen potentiated plasma EPO concentration and EPOR-positive endothelial cell counts. In experiments with hypoxic PH rats' isolated perfused lungs, Gen caused NO- and phosphatidylinositol 3-kinase (PI3K)/Akt-dependent vasodilation that reversed abnormal vasoconstriction. In vitro, a combination of EPO and Gen increased the p-eNOS and the EPOR expression in human umbilical vein endothelial cells under a hypoxic environment. Moreover, Gen potentiated the hypoxic increase in EPO production from human hepatoma cells. We conclude that Gen may be effective for the prevention of hypoxic PH through the improvement of PI3K/Akt-dependent, NO-mediated signaling in association with enhancement of the EPO/EPOR system.


Assuntos
Anti-Hipertensivos/farmacologia , Eritropoetina/biossíntese , Genisteína/farmacologia , Hipertensão Pulmonar/tratamento farmacológico , Óxido Nítrico/fisiologia , Animais , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Hipóxia Celular , GMP Cíclico/metabolismo , Avaliação Pré-Clínica de Medicamentos , Eritropoetina/fisiologia , Genisteína/uso terapêutico , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/fisiopatologia , Hipertrofia Ventricular Direita/prevenção & controle , Masculino , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Processamento de Proteína Pós-Traducional , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Vasodilatadores/farmacologia , Pressão Ventricular
20.
PLoS One ; 9(1): e86459, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24489728

RESUMO

Accumulating evidence indicates that a small population of cancer stem cells (CSCs) is involved in intrinsic resistance to cancer treatment. The hypoxic microenvironment is an important stem cell niche that promotes the persistence of CSCs in tumors. Our aim here was to elucidate the role of hypoxia and CSCs in the resistance to gefitinib in non-small cell lung cancer (NSCLC) with activating epidermal growth factor receptor (EGFR) mutation. NSCLC cell lines, PC9 and HCC827, which express the EGFR exon 19 deletion mutations, were exposed to high concentration of gefitinib under normoxic or hypoxic conditions. Seven days after gefitinib exposure, a small fraction of viable cells were detected, and these were referred to as "gefitinib-resistant persisters" (GRPs). CD133, Oct4, Sox2, Nanog, CXCR4, and ALDH1A1-all genes involved in stemness-were highly expressed in GRPs in PC9 and HCC827 cells, and PC9 GRPs exhibited a high potential for tumorigenicity in vivo. The expression of insulin-like growth factor 1 (IGF1) was also upregulated and IGF1 receptor (IGF1R) was activated on GRPs. Importantly, hypoxic exposure significantly increased sphere formation, reflecting the self-renewal capability, and the population of CD133- and Oct4-positive GRPs. Additionally, hypoxia upregulated IGF1 expression through hypoxia-inducible factor 1α (HIF1α), and markedly promoted the activation of IGF1R on GRPs. Knockdown of IGF1 expression significantly reduced phosphorylated IGF1R-expressing GRPs under hypoxic conditions. Finally, inhibition of HIF1α or IGF1R by specific inhibitors significantly decreased the population of CD133- and Oct4-positive GRPs, which were increased by hypoxia in PC9 and HCC827 cells. Collectively, these findings suggest that hypoxia increased the population of lung CSCs resistant to gefitinib in EGFR mutation-positive NSCLC by activating IGF1R. Targeting the IGF1R pathway may be a promising strategy for overcoming gefitinib resistance in EGFR mutation-positive NSCLC induced by lung CSCs and microenvironment factors such as tumor hypoxia.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/patologia , Quinazolinas/farmacologia , Receptor IGF Tipo 1/metabolismo , Antígeno AC133 , Animais , Antígenos CD/metabolismo , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Carcinogênese/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/genética , Linhagem Celular Tumoral , Separação Celular , Resistencia a Medicamentos Antineoplásicos/genética , Receptores ErbB/genética , Gefitinibe , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glicoproteínas/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Camundongos Endogâmicos NOD , Mutação/genética , Transplante de Neoplasias , Células-Tronco Neoplásicas/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Peptídeos/metabolismo , Quinazolinas/uso terapêutico , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor IGF Tipo 1/genética , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/patologia , Regulação para Cima/efeitos dos fármacos
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