RESUMO
Masaoka stage I type A thymomas rarely recur. We report the case of an 82-year-old man who developed endobronchial metastasis after thymothymectomy for Masaoka stage I type A thymoma. Twenty years after surgery, the patient developed bloody sputum, and chest computed tomography revealed a neoplasm obstructing the right upper lobe bronchus of the lung with enlarged mediastinal lymph nodes. He underwent right upper lobectomy and mediastinal lymph node dissection. Although preoperative pathological diagnosis was squamous cell carcinoma of the lung, postoperative histopathology revealed endobronchial metastasis of the thymoma. Nine years later, at age 89, the patient is alive and well.
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Neoplasias Pulmonares , Timoma , Neoplasias do Timo , Masculino , Humanos , Idoso de 80 Anos ou mais , Timoma/cirurgia , Timoma/patologia , Timoma/secundário , Neoplasias Pulmonares/patologia , Escarro , Recidiva Local de Neoplasia , Neoplasias do Timo/cirurgia , Neoplasias do Timo/patologiaRESUMO
Pulmonary metastatic resection is a standard therapy for renal cell carcinoma (RCC). Although patients with pulmonary metastases who do not undergo any treatment have poor prognoses, it has been reported that resection for pulmonary metastases yields good clinical outcomes. We investigated the prognoses of the 10 Japanese patients (eight males, two females) who underwent a surgical resection of pulmonary metastasectomy from RCC at our institution between April 1, 2012 and March 31, 2020 and analyzed the prognostic factors. We determined the prognoses and calculated the 5-year overall survival (OS) and disease-free survival (DFS) rates. To identify prognostic factors, we compared the median DFS duration for each factor. Elderly patients (median age, 75.5 years) were more predominant compared to previous studies, and all 10 patients underwent a complete resection. The 5-year DFS rate was 30.5% (95%CI: 0.045-0.63) and the 5-year OS rate was 80% (95%CI: 0.20-0.97). The following factors were associated with better prognosis: female, disease-free interval≥36 months, and metastases size<12 mm. These results indicate that complete resection for pulmonary metastases from RCC resulted in good clinical outcomes, particularly for patients with better prognostic factors.
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Carcinoma de Células Renais , Neoplasias Renais , Neoplasias Pulmonares , Metastasectomia , Masculino , Humanos , Feminino , Idoso , Carcinoma de Células Renais/cirurgia , Pneumonectomia/métodos , Neoplasias Pulmonares/secundário , Prognóstico , Taxa de Sobrevida , Neoplasias Renais/cirurgia , Estudos RetrospectivosRESUMO
Aspergillosis is an infection caused by Aspergillus species, and it manifests in various clinical presentations. We describe the case of a 73-year-old man with a small area of thickening on the thoracic wall detected by computed tomography. Surgical resection confirmed the diagnosis of an Aspergillus abscess. We report this case in view of the rarity of Aspergillus abscess localized to a parietal pleura without any signs of lung parenchymal involvement. After a thorough literature review, we consider this could be the first report of this manifestation. Accumulation of similar cases will be necessary to help spread recognition of this condition.
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Aspergilose , Pleura , Abscesso/diagnóstico , Idoso , Aspergilose/complicações , Aspergilose/diagnóstico , Humanos , Pulmão , Masculino , Tomografia Computadorizada por Raios XRESUMO
Small pulmonary lesions are often difficult to localize during thoracoscopic surgery. We describe a new com-puted tomography (CT)-guided pleural dye-marking method for small peripheral pulmonary lesions that does not involve a visceral pleural puncture. We used this technique for 23 lesions (22 patients) who underwent tho-racoscopic partial lung resection (Nov. 2016-Jan. 2018). With the patient in the lateral decubitus position, pre-operative CT-guided marking on the skin over the lesion was performed. During the surgery, we marked the visceral pleura with a skin marker directly or with an infant-size nutrition catheter with crystal violet at the tip through a venous indwelling needle inserted perpendicular to the skin marking. We localized and resected the lesions in all cases, without complications. The median nodule size measured histopathologically was 8 (4-20) mm overall, and 7 (0-20) mm of the solid part; the median distance from the visceral pleura to the nodule was 9 (1-33) mm. The median operation time was 67 (37-180) min. The median postoperative hospital stay was 3 (3-11) days. Our CT-guided pleural dye-marking method is useful and safe for the localization of small periph-eral pulmonary lesions in thoracoscopic partial lung resections.
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Neoplasias Pulmonares/diagnóstico por imagem , Coloração e Rotulagem/métodos , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Violeta Genciana/uso terapêutico , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Toracoscopia/métodosRESUMO
Human epidermal growth factor receptor 2 (HER2) is a member of the HER family of proteins containing four receptor tyrosine kinases. It plays an important role in the pathogenesis of certain human cancers. In non-small-cell lung cancer (NSCLC), HER2 amplification or mutations have been reported. However, little is known about the benefit of HER2-targeted therapy for NSCLCs harboring HER2 alterations. In this study, we investigated the antitumor effect of afatinib, an irreversible epidermal growth factor receptor (EGFR)-HER2 dual inhibitor, in lung cancers harboring HER2 oncogene alterations, including novel HER2 mutations in the transmembrane domain, which we recently identified. Normal bronchial epithelial cells, BEAS-2B, ectopically overexpressing wild-type HER2 or mutants (A775insYVMA, G776VC, G776LC, P780insGSP, V659E, and G660D) showed constitutive autophosphorylation of HER2 and activation of downstream signaling. They were sensitive to afatinib, but insensitive to gefitinib. Furthermore, we examined the antitumor activity of afatinib and gefitinib in several NSCLC cell lines, and investigated the association between their genetic alterations and sensitivity to afatinib treatment. In HER2-altered NSCLC cells (H2170, Calu-3, and H1781), afatinib downregulated the phosphorylation of HER2 and EGFR as well as their downstream signaling, and induced an antiproliferative effect through G1 arrest and apoptotic cell death. In contrast, HER2- or EGFR-non-dependent NSCLC cells were insensitive to afatinib. In addition, these effects were confirmed in vivo by using a xenograft mouse model of HER2-altered lung cancer cells. Our results suggest that afatinib is a therapeutic option as a HER2-targeted therapy for NSCLC harboring HER2 amplification or mutations.
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Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Quinazolinas/farmacologia , Receptor ErbB-2/genética , Afatinib , Animais , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Feminino , Genes erbB-2 , Humanos , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Reação em Cadeia da Polimerase em Tempo Real , Transfecção , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
A study to evaluate the effect of metformin on the immune system was commenced in July 2014. Metformin is one of the most commonly prescribed drugs for type 2 diabetes, and previous studies have reported that metformin has an anti-tumor effect. The aim of this study is to evaluate the efficacy of metformin on the immune system in human cancer patients in vivo. The primary outcome parameter will be the rate change in the population of CD8ï¼ T cells, which produce multiple cytokines.
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Linfócitos T CD8-Positivos/fisiologia , Citocinas/metabolismo , Metformina/farmacologia , Neoplasias/imunologia , Protocolos Clínicos , Citocinas/genética , Humanos , Hipoglicemiantes/farmacologiaRESUMO
Afatinib is an irreversible epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) that is known to be effective against the EGFR T790M variant, which accounts for half of the mechanisms of acquired resistance to reversible EGFR-TKIs. However, acquired resistance to afatinib was also observed in clinical use. Thus, elucidating and overcoming the mechanisms of resistance are important issues in the treatment of non-small cell lung cancer. In this study, we established various afatinib-resistant cell lines and investigated the resistance mechanisms. EGFR T790M mutations were not detected using direct sequencing in established resistant cells. Several afatinib-resistant cell lines displayed MET amplification, and these cells were sensitive to the combination of afatinib plus crizotinib. As a further investigation, a cell line that acquired resistance to afatinib plus crizotinib, HCC827-ACR, was established from one of the MET amplified-cell lines. Several afatinib-resistant cell lines including HCC827-ACR displayed epithelial-to-mesenchymal transition (EMT) features and epigenetic silencing of miR-200c, which is a suppresser of EMT. In addition, these cell lines also exhibited overexpression of ALDH1A1 and ABCB1, which are putative stem cell markers, and resistance to docetaxel. In conclusion, we established afatinib-resistant cells and found that MET amplification, EMT, and stem cell-like features are observed in cells with acquired resistance to EGFR-TKIs. This finding may provide clues to overcoming resistance to EGFR-TKIs.
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Carcinoma Pulmonar de Células não Pequenas/patologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/biossíntese , Afatinib , Aldeído Desidrogenase/biossíntese , Família Aldeído Desidrogenase 1 , Animais , Antineoplásicos/farmacologia , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Proliferação de Células , Crizotinibe , Metilação de DNA/genética , Docetaxel , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Receptores ErbB/antagonistas & inibidores , Feminino , Humanos , Neoplasias Pulmonares/genética , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , MicroRNAs/genética , Mutação/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Pirazóis/farmacologia , Piridinas/farmacologia , Retinal Desidrogenase , Análise de Sequência de DNA , Taxoides/farmacologiaRESUMO
Malignant melanoma is a refractory malignancy with a dismal prognosis. It generally arises from the skin in most cases, and cases of primary pulmonary malignant melanoma are rare and often behave aggressively. We have treated two cases of localized primary pulmonary malignant melanoma using surgical resection. Pulmonary malignant melanomas often metastasize to the brain and liver; one of our cases exhibited metastasis to the cecum at about 8 months after surgery. Because cutaneous melanomas often carry activating mutations in the BRAF gene (V600E), we performed a BRAF mutational analysis using direct sequencing for both of these tumors arising from the lung. However, no BRAF mutations were detected. We detected a p53 mutation, which was thought to be a potential somatic mutation, in one of the two cases using a sequencing panel targeting 20 lung cancer-related genes. Although we also checked the expression of programmed death ligand 1 (PD-L1) on the surface of the tumor cells by immunohistochemical testing, neither of our two cases expressed PD-L1. Further molecular analyses may uncover the characteristics of primary pulmonary malignant melanomas.
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Neoplasias Pulmonares/genética , Neoplasias Pulmonares/cirurgia , Melanoma/genética , Melanoma/cirurgia , Idoso , Antígeno B7-H1/genética , Broncoscopia/métodos , Análise Mutacional de DNA , Feminino , Perfilação da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Mutação/genética , Pneumonectomia , Reação em Cadeia da Polimerase , Prognóstico , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas , Proteína Supressora de Tumor p53/genética , Melanoma Maligno CutâneoRESUMO
Background: Respiratory impairment can lead to pulmonary complications after surgery; therefore, it should be considered when determining the choice of surgical procedure. Several studies have examined the relationship between preoperative respiratory function and postoperative mortality and morbidity after lung resection; however, there are no indicators for limited surgical procedure selection. The aim of this study was to examine the association between preoperative respiratory function and postoperative early and late complications, recurrence-free survival (RFS), and overall survival (OS) in patients undergoing pulmonary resection for stage I lung cancer. Methods: We performed a retrospective analysis of data from 192 patients undergoing pulmonary resection for primary pathological stage IA non-small cell lung cancer (NSCLC) at the Iwakuni Clinical Center in Japan between 2012 and 2015. We reviewed clinicopathological characteristics including preoperative pulmonary function and elucidated the relationship between them and postoperative survival. Results: Obstructive ventilatory impairment was present in 55 patients (28.6%), and restrictive ventilatory impairment was present in 31 patients (16.1%). Seven patients (3.6%) had both ventilatory impairment. Obstructive ventilatory impairment did not affect the 5-year RFS (P=0.08) or OS (P=0.21). However, restrictive ventilatory impairment reduced the 5-year RFS (P=0.002) and OS (P=0.009). The rates of early and late complications were not significantly different based on the preoperative respiratory function. Conclusions: In patients with preoperative restrictive ventilatory impairment in whom lobectomy or segmentectomy cannot be performed, careful consideration is needed for surgical indications.
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Heat-killed Lactiplantibacillus plantarum L-137 (HK L-137) has been suggested to enhance the intestinal barrier in obese mice, leading to improvement of metabolic abnormalities and adipose tissue inflammation, and in healthy humans with overweight, leading to improvement of systemic inflammation. However, its detailed mechanism of action has not been clarified. Therefore, this study investigated the effects of HK L-137 on the permeability of rat small intestinal epithelial IEC-6 cells, tight junction-related gene and protein expression and localization, and intracellular signaling pathways involved in barrier function. Treatment of IEC-6 cells with HK L-137 for 26 h significantly reduced the permeability to fluorescein isothiocyanate-dextran (FD-4). HK L-137 also increased gene and protein expression of zonula occludens-1 (ZO-1), an important tight junction protein, without affecting the localization. Furthermore, inhibition of the extracellular signal-regulated kinase (ERK)1/2 pathway in IEC-6 cells canceled the HK L-137-related reduction in permeability to FD-4. Phosphorylation of ERK in IEC-6 cells was induced 15 min after the addition of HK L-137. These results suggest that HK L-137 reduces intestinal permeability partly through activating the ERK pathway and increasing expression of the ZO-1 gene and protein. Enhancement of intestinal barrier function with HK L-137 might be effective in preventing and treating leaky gut, for which no specific therapeutic tool has been established.
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Células Epiteliais , Mucosa Intestinal , Proteína da Zônula de Oclusão-1 , Animais , Ratos , Proteína da Zônula de Oclusão-1/metabolismo , Proteína da Zônula de Oclusão-1/genética , Células Epiteliais/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Linhagem Celular , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Probióticos/farmacologia , Permeabilidade , Lactobacillus plantarum/fisiologia , Junções Íntimas/metabolismo , Temperatura Alta , Sistema de Sinalização das MAP Quinases , Fosforilação , Função da Barreira IntestinalRESUMO
It is difficult to cure recurrent or metastatic breast cancer (MBC). Therefore, it is important to continue treatment for MBC with maintenance of quality of life (QOL). Gemcitabine has been approved for MBC since February 2010. We administered gemcitabine to 39 patients with MBC between February 1, 2010 and March 31, 2012. Depending on the case, taxane or trastuzumab was added. Almost all patients had received prior chemotherapy or hormonal therapy. The median age of patients was 61 years (range, 33-82 years), and the median number of previous treatment regimens was 3 (range, 0-6). The response rate was 15.4%, the disease control rate was 56.4%, and the clinical benefit rate was 33.3%. The main hematological adverse event was neutropenia, and the main non-hematological adverse event was fatigue. Neutropenia could be managed by reducing the gemcitabine dose or withdrawing treatment. Adverse events requiring hospitalization were not observed. These findings suggest that gemcitabine-based regimens are feasible in terms of efficacy and maintenance of QOL for patients with MBC.
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Neoplasias da Mama/tratamento farmacológico , Desoxicitidina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Desoxicitidina/efeitos adversos , Desoxicitidina/uso terapêutico , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Qualidade de Vida , Recidiva , GencitabinaRESUMO
We herein report two cases of thymic cancer with Lynch syndrome showing a high frequency of microsatellite instability and loss of mismatch repair protein expression without MLH1 promoter hyper-methylation. In Case 1, a 71-year-old man had a pathogenic germline variant in MLH1 and underwent tumor resection. No relapse has been reported thus far. In Case 2, a 43-year-old man underwent genetic testing that also showed a pathogenic germline variant in MLH1. Since these two cases had MLH variants, we suspect a possible association between thymic cancer with Lynch syndrome and germline pathogenic variants in MLH1.
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Neoplasias Colorretais Hereditárias sem Polipose , Neoplasias do Timo , Masculino , Humanos , Idoso , Adulto , Neoplasias Colorretais Hereditárias sem Polipose/complicações , Neoplasias Colorretais Hereditárias sem Polipose/genética , Metilação de DNA/genética , Proteína 1 Homóloga a MutL/genética , Recidiva Local de Neoplasia/genética , Mutação em Linhagem Germinativa , Neoplasias do Timo/complicações , Neoplasias do Timo/genética , Neoplasias do Timo/cirurgiaRESUMO
OBJECTIVES: Ipsilateral reoperation after pulmonary lobectomy is often challenging because of adhesions from the previous operation. We retrospectively examined the surgical outcome and prognosis of ipsilateral anatomical resection for lung cancer after pulmonary lobectomy using a multicentre database. METHODS: We evaluated the perioperative outcomes and overall survival of 51 patients who underwent pulmonary lobectomy followed by ipsilateral anatomical resection for lung cancer between January 2012 and December 2018. In addition, patients with stage I non-small-cell lung cancer (NSCLC) were compared with 3411 patients with stage I lung cancer who underwent pulmonary resection without a prior ipsilateral lobectomy. RESULTS: Ipsilateral anatomical resections included 10 completion pneumonectomies, 19 pulmonary lobectomies and 22 pulmonary segmentectomies. Operative time was 312.2 ± 134.5 min, and intraoperative bleeding was 522.2 ± 797.5 ml. Intraoperative and postoperative complications occurred in 9 and 15 patients, respectively. However, the 5-year overall survival rate after anatomical resection followed by ipsilateral lobectomy was 83.5%. Furthermore, in patients with c-stage I NSCLC, anatomical resection followed by ipsilateral lobectomy was not associated with worse survival than anatomical resection without prior ipsilateral lobectomy. CONCLUSIONS: Anatomical resection following ipsilateral lobectomy is associated with a high frequency of intraoperative and postoperative complications. However, the 5-year overall survival in patients with c-stage I NSCLC who underwent ipsilateral anatomical resection after pulmonary lobectomy is comparable to that in patients who underwent anatomical resection without prior pulmonary lobectomy.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Estudos Retrospectivos , Pneumonectomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento , Estadiamento de NeoplasiasRESUMO
There are numerous cultivars of tea (Camellia sinensis L.), but the differences in their anti-hyperglycemic-related effects are largely unknown. The inhibition of the dipeptidyl peptidase (DPP)-IV enzyme plays an essential role in controlling hyperglycemia in diabetes by blocking the degradation of incretin hormones, which is necessary for insulin secretion. In this study, we examined the DPP-IV inhibitory activity of leaf extracts from diverse Japanese green tea cultivars. The inhibitory rates differed among tea extracts. Metabolic profiling (MP), using liquid chromatography-mass spectrometry, of all cultivars revealed compositional differences among cultivars according to their DPP-IV inhibitory capacity. Epigallocatechin-3-O-(3-O-methyl)gallate, kaempferol-3-O-rutinoside, myricetin-3-O-glucoside/galactoside, and theogallin were newly identified as DPP-IV inhibitors. The bioactivity of a tea extract was potentiated by adding these ingredients in combination. Our results show that MP is a useful approach for evaluating the DPP-IV inhibitory potency of green tea and for determining bioactivity-related ingredients and combinations.
Assuntos
Camellia sinensis , Inibidores da Dipeptidil Peptidase IV , Camellia sinensis/química , Dipeptidil Peptidase 4 , Inibidores da Dipeptidil Peptidase IV/química , Metabolômica/métodos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Chá/químicaRESUMO
BACKGROUND: In survivors of head and neck cancer (HNC), second primary lung cancer (SPLC) often develop as a result of a common risk factor, that is, smoking. A multicenter experience was reviewed to evaluate how the history of a diagnosis of HNC affects the outcomes of patients undergoing pulmonary resection for SPLC. METHODS: A multicenter retrospective analysis of patients hospitalized between January 2012 and December 2018 was performed. From a cohort of 4521 patients undergoing therapeutic pulmonary resection for primary non-small cell lung cancer, 100 patients with a previous history of HNC (HNC group) were identified. These patients were compared with a control group consisting of 200 patients without an HNC history from the same cohort pair-matched with operating facility, age, sex, and pathologic stage of lung cancer. RESULTS: At the time of surgery for SPLC, the HNC group showed malnutrition with a lower prognostic nutritional index compared with the control group (P < .001). The HNC group was determined to have postoperative complications more frequently (P = .02). The 5-year overall survival rates in the HNC and control groups were 59.0% and 83.2%, respectively (P < .001). Statistically, HNC history, lower prognostic nutritional index, squamous cell lung cancer, and TNM stage were identified to be independently associated with poor survival. CONCLUSIONS: Patients with SPLC after primary HNC often present with malnutrition and are predisposed to postoperative complications and poor survival after pulmonary resection.
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BACKGROUND: No established treatments for pulmonary pleomorphic carcinoma exist because of its rarity, and the prognosis is poorer than that of other non-small cell lung cancers. CASE REPORT: We present a case of stage IV pleomorphic carcinoma; the patient was a 66-year-old male. He was referred to our hospital because of a right adrenal hemorrhage and a lung tumor. A systemic examination revealed that the lung tumor was a primary lung cancer and that the adrenal hemorrhage was due to a metastatic cancer. We performed an adrenalectomy and resection of the lung tumor and obtained a diagnosis of pleomorphic carcinoma with adrenal metastasis. The patient has remained recurrence-free for 6 years since the surgery. CONCLUSIONS: We report a patient with stage IV pleomorphic carcinoma of the lung and an oligometastasis in whom a complete resection enabled a good outcome. Additional reports are needed to clarify definite prognostic factors and the optimal treatment for pleomorphic carcinoma.
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MicroRNA (miR)-200 family members (miR-200s) are frequently silenced in advanced cancer and have been implicated in the process of epithelial-to-mesenchymal transition (EMT). We previously reported that miR-200s were silenced through promoter methylation in acquired EGFR-tyrosine kinase inhibitor (TKI) resistant non-small cell lung cancer (NSCLC) cells harboring EMT features. In this study, we examined the functional role of miR-200s in NSCLC cells and investigated a novel approach to overcoming acquired EGFR-TKI resistance. In the analysis of NSCLC cell lines, each of the miR-200s expression-silenced cell lines showed promoter methylation. Significant correlations between miR-200c silencing and several oncogenic pathway alterations, including EMT-changes and LIN28B overexpression, were observed in the database analysis. In addition, EGFR-wild type cell lines had lower miR-200s expression levels than EGFR-mutant cell lines. The introduction of miR-200c using pre-miR-200c caused LIN28B suppression in cells with acquired EGFR-TKI resistance that harbored EMT features. Interestingly, both the introduction of miR-200c and the knockdown of LIN28B produced an antitumor effect in acquired EGFR-TKI resistance cells, whereas these manipulations were not effective in parental cells. The miR-200c/LIN28B axis plays an important role in cells with acquired resistance to EGFR-TKI that harbor EMT features and might be a useful therapeutic target for overcoming resistance.
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Carcinoma Pulmonar de Células não Pequenas/metabolismo , Resistencia a Medicamentos Antineoplásicos , Receptores ErbB/antagonistas & inibidores , Neoplasias Pulmonares/metabolismo , MicroRNAs/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas de Ligação a RNA/genética , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Células HEK293 , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , MicroRNAs/metabolismo , Proteínas de Ligação a RNA/metabolismoRESUMO
Docetaxel is a third-generation chemotherapeutic drug that is widely used in the treatment of patients with non-small cell lung cancer (NSCLC). However, the majority of patients with NSCLC eventually acquire resistance to the treatment. In the present study, the mechanism of acquired resistance to docetaxel treatment in lung cancer cells was investigated. The three NSCLC cell lines, H1299 with wild-type epidermal growth factor receptor (EGFR), EGFR-mutant HCC4006 and HCC827, and experimentally established docetaxel-resistant (DR) cells, H1299-DR, HCC827-DR, and HCC4006-DR were used with stepwise increases in concentrations of docetaxel. It was demonstrated that the established cell lines showed resistance to docetaxel and EGFR-tyrosine kinase inhibitors (TKIs). Molecular analysis revealed that all of the resistant cell lines highly expressed ATP binding cassette subfamily B member 1 (ABCB1), which is also known as P-glycoprotein or MDR1. Furthermore, HCC827-DR and HCC4006-DR cells exhibited a cancer stem cell-like marker and epithelial-to-mesenchymal transition features, respectively. Elacridar (GF120918), a third-generation inhibitor of ABCB1, was able to overcome resistance to docetaxel. Additionally, knockdown of ABCB1 using small interfering RNA (si)-ABCB1 recovered sensitivity to docetaxel. However, elacridar and si-ABCB1 could not recover sensitivity to EGFR-TKIs in established resistant cells. The results of the present study revealed that docetaxel-resistant NSCLC cells also acquired cross-resistance to EGFR-TKI therapy through mechanisms other than ABCB1, that ABCB1 serves an important role in acquired resistance to docetaxel in lung cancer, and that combination therapy with elacridar can overcome ABCB1-mediated docetaxel resistance.
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Techniques for the extraction and use of nucleic acids from formalin-fixed and paraffin-embedded (FFPE) tissues, preserved over long time periods in libraries, have been developed. However, DNA extracted from FFPE tissues is generally damaged, and long-term storage may affect DNA quality. Therefore, it is important to elucidate the effect of long-term storage on FFPE tissues and evaluate the techniques used to extract DNA from them. In the present study, the yield, purity, and integrity of DNA in FFPE tissue samples was evaluated. Two DNA extraction techniques were used: A silica-binding DNA collection method using QIAamp DNA FFPE Tissue kit (QIA) and a total tissue DNA collection method using a WaxFree DNA extraction kit (WAX). A total of 25 FFPE tissues from lung adenocarcinomas were studied, which had been surgically resected and fixed at Okayama University Hospital prior to examination and subsequent storage at room temperature for 0.5, 3, 6, 9 and 12 years. Extracted DNA was quantified using ultraviolet absorbance, fluorescent dye, and quantitative polymerase chain reaction (qPCR). The quality of the DNA was defined by the absorbance ratio of 260 to 280 nm (A260/280) and Q-score, which is the quantitative value of qPCR product size ratio. The results demonstrated that the yield of total DNA extracted using WAX was significantly greater than when QIA was used (P<0.01); however, DNA extracted using WAX included more contaminants and was significantly more fragmented compared with DNA extracted using QIA (P<0.01). Aging had no significant effect on absolute DNA yield or DNA purity, although it did significantly contribute to increased DNA degradation for both QIA and WAX extraction (QIA P=0.02, WAX P=0.03; 0.5 years vs. 3 years, QIA P<0.01, WAX P=0.03; 9 years vs. 12 years). Both extraction methods are viable depending on whether high yield or high quality of extracted DNA is required. However, due to the increased degradation with age, storage time limits the available DNA in FFPE tissues regardless of the extraction method.
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BACKGROUND: Overexpression of human epidermal growth factor receptor 2 (HER2) is observed in approximately 15-23% of breast cancers and these cancers are classified as HER2-positive breast cancer. Trastuzumab is the first-line targeted therapeutic drug for HER2-positive breast cancer and has improved patient overall survival. However, acquired resistance to trastuzumab is still a critical issue in breast cancer treatment. We previously established a trastuzumab-resistant breast cancer cell line (named as BT-474-R) from a trastuzumab-sensitive HER2-amplified cell line BT-474. Lapatinib is also a molecular-targeted drug for HER2-positive breast cancer, which acquired the resistance to trastuzumab. Acquired resistance to lapatinib is also an issue to be conquered. METHODS: We established trastuzumab/lapatinib-dual resistant cell line (named as BT-474-RL2) by additionally treating BT-474-R with lapatinib. We analyzed the mechanisms of resistance to trastuzumab and lapatinib. Besides, we analyzed the effect of the detected resistance mechanism in HER2-positive breast cancer patients. RESULTS: Proto-oncogene tyrosine-protein kinase Yes1, which is one of the Src family members, was amplified, overexpressed and activated in BT-474-R and BT-474-RL2. Silencing of Yes1 by siRNA induced both BT-474-R and BT-474-RL2 to restore the sensitivity to trastuzumab and lapatinib. Pharmaceutical inhibition of Yes1 by the Src inhibitor dasatinib was also effective to restore the sensitivity to trastuzumab and lapatinib in the two resistant cell lines. Combination treatment with dasatinib and trastuzumab induced down-regulation of signaling molecules such as HER2 and Akt. Moreover, the combination treatments induced G1-phase cell-cycle arrest and apoptosis. Consistent with cell line data, high expression of Yes1 mRNA was correlated with worse prognosis in patients with HER2-positive breast cancer. CONCLUSION: Yes1 plays an important role in acquired resistance to trastuzumab and lapatinib in HER2-positive breast cancer. Our data suggest that pharmacological inhibition of Yes1 may be an effective strategy to overcome resistance to trastuzumab and lapatinib.