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PURPOSE: To investigate the clinical characteristics of lung cancer that develops after kidney transplantation. METHODS: The clinical data of patients with lung cancer diagnosed after kidney transplantation were collected retrospectively. The medical records were extracted from our database. All patients underwent routine chest examination after kidney transplantation. RESULTS: In total, 17 lung tumors were detected in 15 (0.6%) of 2593 patients who underwent kidney transplantation at our institution. Eleven lung tumors were completely resected from a collective 10 patients (surgical group). The remaining five patients did not receive surgical treatment (nonsurgical group). The surgical group underwent wedge resection (n = 5), segmentectomy (n = 1), lobectomy (n = 3), and bilobectomy (n = 1). The pathological stages were 0 (n = 1), IA1 (n = 2), IA2 (n = 4), IA3 (n = 2), and IB (n = 1). The surgical group had a significantly better prognosis than the nonsurgical group. There were no perioperative complications related to kidney transplantation in either group. CONCLUSIONS: Routine chest examination would be useful for the early diagnosis and treatment of lung cancer after kidney transplantation. Moreover, surgical resection for early-stage lung cancer was associated with a better prognosis for kidney transplantation patients.
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We have experienced a case of delayed tracheal perforation after pulmonary resection using soft coagulation system. A 58-year-old male underwent operation for primary lung cancer. A soft coagulation system was used for oozing near upper mediastinal lymph nodes. The patient was discharged on postoperative day 8 in a good condition, however sudden tracheal perforation and was occurred on postoperative day 30. An emergency operation revealed that improper use of the soft coagulation system might cause a necrosis of the bronchial wall. Although, a soft coagulation system is useful to control bleeding from small vessels such as bronchial arteries and lymph nodes, this system is different from conventional electrocautery and requires some attention when using.
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Neoplasias Pulmonares/cirurgia , Pneumonectomia/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Traqueia/lesões , Doenças da Traqueia/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças da Traqueia/etiologiaRESUMO
INTRODUCTION: Thoracoscopic surgery is performed for refractory or recurrent primary spontaneous pneumothorax (PSP). To reduce postoperative recurrence, additional treatment is occasionally adopted during surgery after bulla resection. However, the most effective method has not been fully elucidated. Furthermore, the preference for additional treatment varies among countries, and its efficacy in preventing recurrence must be evaluated based on settings tailored for the conditions of a specific country. The number of registries collecting detailed data about PSP surgery is limited. Therefore, to address this issue, a prospective multicentre observational study was performed. METHODS AND ANALYSIS: This multicentre, prospective, observational study will enrol 450 participants aged between 16 and 40 years who initially underwent PSP surgery. Data about demographic characteristics, disease and family history, surgical details, and CT scan findings will be collected. Follow-up must be conducted until 3 years after surgery or in the event of recurrence, whichever came first. Patients without recurrence will undergo annual follow-up until 3 years after surgery. The primary outcome is the rate of recurrence within 2 years after surgery. A multivariate analysis will be performed to compare the efficacy of different surgical options. Then, adverse outcomes correlated with various treatments and the feasibility of treatment methods will be compared. ETHICS AND DISSEMINATION: This study was approved by the local ethics committee of all participating centres. The findings will be available in 2025, and they can be used as a basis for clinical decision-making regarding appropriate options for the initial PSP surgery. TRIAL REGISTRATION NUMBER: NCT04758143.
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Pneumotórax , Adolescente , Adulto , Humanos , Estudos Multicêntricos como Assunto , Estudos Observacionais como Assunto , Pneumotórax/prevenção & controle , Pneumotórax/cirurgia , Estudos Prospectivos , Recidiva , Projetos de Pesquisa , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Secreted frizzled related protein 1 (SFRP 1) is an antagonist of the transmembrane frizzled receptor, a component of the Wnt signaling pathway, and has been suggested to be a candidate tumor suppressor in several human malignancies. Since SFRP 1 is located at chromosome 8 p 11, where lung cancers also exhibit frequent allelic loss, we hypothesized that the inactivation of SFRP 1 is also involved in lung carcinogenesis. To substantiate this, we performed mutational analysis of SFRP 1 for 29 non-small-cell lung cancer (NSCLC) and 25 small-cell lung cancer (SCLC) cell lines, and expression analysis for the same cell lines. Although somatic mutations were not detected in the coding sequence, downregulation of SFRP 1 was observed in 14 (48%) NSCLC and nine (36%) SCLC cell lines. We analysed epigenetic alteration of the SFRP 1 promoter region and detected hypermethylation in 15 (52%) of 29 NSCLC cell lines, two (8%) of 25 SCLC cell lines, and 44 (55%) of 80 primary lung tumors. By comparing the methylation status with SFRP 1 expression, we found a significant correlation between them. We also performed loss of heterozygosity (LOH) analysis and found that 15 (38%) of 40 informative surgical specimens had LOH in the SFRP 1 gene locus. Furthermore, we performed colony formation assay of two NSCLC cell lines (NCI-H 460 and NCI-H 2009) and found the reduction of colony formation with SFRP 1 transfection. In addition, we also detected that SFRP 1 inhibits the transcriptional activity of beta-catenin, which is thought to be a downstream molecule of SFRP 1, with luciferase reporter assay. Our current studies demonstrated that the SFRP 1 gene is frequently downregulated by promoter hypermethylation and suppresses tumor growth activity of lung cancer cells, which suggests that SFRP 1 is a candidate tumor suppressor gene for lung cancer.
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Carcinoma Pulmonar de Células não Pequenas/genética , Metilação de DNA , Inativação Gênica , Peptídeos e Proteínas de Sinalização Intercelular/genética , Neoplasias Pulmonares/genética , Proteínas de Membrana/genética , Regiões Promotoras Genéticas , Transcrição Gênica , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Primers do DNA , Humanos , Neoplasias Pulmonares/patologiaRESUMO
Birt-Hogg-Dubé syndrome (BHD) is an inherited disorder caused by genetic mutations in the folliculin (FLCN) gene. Individuals with BHD have multiple pulmonary cysts and are at a high risk for developing renal cell carcinomas (RCCs). Currently, little information is available about whether pulmonary cysts are absolutely benign or if the lungs are at an increased risk for developing neoplasms. Herein, we describe 14 pulmonary neoplastic lesions in 7 patients with BHD. All patients were confirmed to have germline FLCN mutations. Neoplasm histologies included adenocarcinoma in situ (n = 2), minimally invasive adenocarcinoma (n = 1), papillary adenocarcinoma (n = 1), micropapillary adenocarcinoma (n = 1), atypical adenomatous hyperplasia (n = 8), and micronodular pneumocyte hyperplasia (MPH)-like lesion (n = 1). Five of the six adenocarcinoma/MPH-like lesions (83.3%) demonstrated a loss of heterozygosity (LOH) of FLCN. All of these lesions lacked mutant alleles and preserved wild-type alleles. Three invasive adenocarcinomas possessed additional somatic events: 2 had a somatic mutation in the epidermal growth factor receptor gene (EGFR) and another had a somatic mutation in KRAS. Immunohistochemical analysis revealed that most of the lesions were immunostained for phospho-mammalian target of rapamycin (p-mTOR) and phospho-S6. Collective data indicated that pulmonary neoplasms of peripheral adenocarcinomatous lineage in BHD patients frequently exhibit LOH of FLCN with mTOR pathway signaling. Additional driver gene mutations were detected only in invasive cases, suggesting that FLCN LOH may be an underlying abnormality that cooperates with major driver gene mutations in the progression of pulmonary adenocarcinomas in BHD patients.
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Síndrome de Birt-Hogg-Dubé/genética , Síndrome de Birt-Hogg-Dubé/patologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Adenocarcinoma/complicações , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Idoso , Células Epiteliais Alveolares/patologia , Sequência de Bases , Síndrome de Birt-Hogg-Dubé/complicações , Análise Mutacional de DNA , Feminino , Mutação em Linhagem Germinativa/genética , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Fosforilação , Transdução de Sinais/genética , Serina-Treonina Quinases TOR/metabolismoRESUMO
We have found that a malignant mesothelioma cell line, NCI-H28, had a chromosome 3p21.3 homozygous deletion containing the beta-catenin gene (CTNNB1), which suggested that the deletion of beta-catenin might have a growth advantage in the development of this tumor. To determine whether beta-catenin has a growth-inhibitory activity, we transfected wild-type beta-catenin, Ser37Cys mutant beta-catenin as an activated type, and C-terminus deletion mutant beta-catenin that lacks the transcription activity, into the NCI-H28 cells. A non-small cell lung cancer cell line, NCI-H1299, which expressed endogenous beta-catenin, was also studied. We tested the localization of exogenous beta-catenin in the NCI-H28 cells with immunofluorescence, and found that the wild-type beta-catenin and the C-terminus deletion mutant were more strongly expressed in the plasma membrane and cytoplasm than in the nucleus, while the Ser37Cys mutant was more in the nucleus than in the cytoplasm. By using luciferase-reporter assay, the beta-catenin/T-cell factor 4-mediated transactivity of the Ser37Cys mutant was shown to be higher than that of the wild-type beta-catenin in both cell lines. However, the transactivity of the C-terminus deletion mutant was strongly reduced in both. Colony formation of the NCI-H28 cells was reduced by 50% after transfection with the wild-type beta-catenin, and 60% with the Ser37Cys mutant, but only 20% with the C-terminus deletion mutant compared to the vector control. Inhibition of colony formation in NCI-H28 cells was because of apoptosis, manifested by positive staining of Annexin V and TUNEL assays in transfected cells. In contrast, when transfected with the wild-type beta-catenin, no significant reduction in colony formation was seen in beta-catenin wild-type NCI-H1299 cells. In conclusion, our data indicate that inactivation of beta-catenin by a 3p21.3 homozygous deletion might be a crucial event in the development of the mesothelioma NCI-H28 cells. Thus, while beta-catenin is well known to be a positive growth-stimulating factor for many human cancers, it can also act as a potential growth suppressor in some types of human cancer cells.
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Cromossomos Humanos Par 3 , Proteínas do Citoesqueleto/genética , Genes Supressores de Tumor , Mesotelioma/genética , Mesotelioma/patologia , Transativadores/genética , Anexina A5/metabolismo , Apoptose/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/genética , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Cisteína/genética , Citoplasma/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas do Citoesqueleto/farmacologia , Regulação Neoplásica da Expressão Gênica , Homozigoto , Humanos , Marcação In Situ das Extremidades Cortadas , Mesotelioma/terapia , Mutação , Células-Tronco Neoplásicas , Deleção de Sequência , Serina/genética , Transativadores/metabolismo , Transativadores/farmacologia , Transcrição Gênica , Células Tumorais Cultivadas , beta CateninaRESUMO
Non-small cell lung cancer frequently shows loss of heterozygosity of the chromosome 3p21.3 region and several genes such as RASSF1A, BLU, and SEMA3B have been identified as candidate tumor suppressor genes at this region since their downregulation and hypermethylation at their promoter regions were frequently detected in lung cancer. To determine whether these three genes are simultaneously inactivated during lung cancer development, we studied 138 primary non-small cell lung cancers for the promoter methylation status of these genes and allelic loss of the chromosome 3p21.3 region. We found promoter hypermethylation at 32% in RASSF1A, 30% in BLU, and 47% in SEMA3B. Allelic loss of 3p21.3 was detected in 54 (58%) of 93 informative tumors. Despite the weak association of methylation status among these three genes, there was no correlation between the methylation status of each gene and loss of heterozygosity. We also studied possible genes downstream of RASSF1A in 16 primary non-small cell lung cancers and found that the expressions of SM22 and SPARC were significantly downregulated in RASSF1A-hypermethylated tumors. Our results showed that, while candidate tumor suppressor genes at this locus can be simultaneously inactivated by epigenetic alterations, loss of heterozygosity without any hypermethylation of the three genes can also occur in some cases, suggesting that just one allelic loss might also be sufficient for the inactivation of any of these genes for lung cancer development.
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Carcinoma Pulmonar de Células não Pequenas/genética , Cromossomos Humanos Par 3 , Metilação de DNA , Perda de Heterozigosidade , Neoplasias Pulmonares/genética , Glicoproteínas de Membrana/genética , Proteínas/genética , Proteínas Supressoras de Tumor/genética , Idoso , Proteínas do Citoesqueleto , Feminino , Genes Supressores de Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas , SemaforinasRESUMO
The epidermal growth factor receptor (EGFR) gene has recently been reported to be mutated in a subset of non-small cell lung cancers (NSCLC), with the mutations being correlated with the patients' drug sensitivity to gefitinib, an EGFR kinase inhibitor. In this study, we searched for EGFR mutations in patients with lung cancer using primary tumor specimens obtained at initial surgery and examined whether their recurrent tumors showed a response to gefitinib depending on the presence of the activating mutation. Among 12 lung cancers that were treated with gefitinib after recurrence, we found that all four tumors which showed a response to gefitinib had an activating mutation in EGFR, whereas none of the remaining eight tumors had a mutation. Southern blot analysis showed that two of the four responsive tumors had the EGFR gene amplification. We also examined another 73 NSCLC specimens (47 males and 26 females; 53 adenocarcinomas and 20 non-adenocarcinomas) which were not treated with gefitinib to determine whether NSCLCs with an EGFR mutation have different clinicopathological properties and/or unique genetic alterations of the other cancer-associated genes. We found that 13 (18%) of 73 tumors had a mutation of the EGFR gene, with the most being detected in female adenocarcinomas. Comparing the alterations in KRAS and P53 with the EGFR mutation, we found that 10 tumors with the KRAS mutation did not have an EGFR mutation, suggesting that each mutation occurs exclusively during the development of lung cancer. These results suggest that the mutation analysis of the EGFR gene using the specimens obtained at surgery might be useful in selecting the appropriate treatment(s) for recurrent lung cancer patients.
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Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação/genética , Quinazolinas/uso terapêutico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/etiologia , Adenocarcinoma/genética , Adenocarcinoma/cirurgia , Idoso , Sequência de Bases , Carcinoma Pulmonar de Células não Pequenas/etiologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Terapia Combinada , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Gefitinibe , Amplificação de Genes , Genes ras , Humanos , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/cirurgia , Estudos Retrospectivos , Sensibilidade e Especificidade , Caracteres SexuaisRESUMO
We report the case of a 29-year-old woman who experienced recurrence of catamenial pneumothorax during pregnancy. Pneumothorax unrelated to the hormonal cycle occurred by pulmonary endometriosis. Thoracoscopic resection of cystic lesions and pleurodesis effectively controlled the pneumothorax.
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Menstruação , Pneumotórax/cirurgia , Complicações na Gravidez/cirurgia , Adulto , Endométrio/patologia , Feminino , Fístula/cirurgia , Humanos , Doenças Pleurais/cirurgia , Pneumotórax/diagnóstico por imagem , Pneumotórax/fisiopatologia , Gravidez , Complicações na Gravidez/fisiopatologia , Recidiva , Tomografia Computadorizada por Raios XRESUMO
A 46-year-old man was referred to our hospital for the treatment of lung cancer. Computed tomography showed a well-defined tumor mass that was 50x45 mm in size and contained a trabecular pattern of calcification. Since he was diagnosed as having a primary lung adenocarcinoma (clinical stage IB), a left upper lobectomy with mediastinal lymph node dissection was performed. Histologically, the tumor was a poorly differentiated adenocarcinoma with rich fibrous stroma, in which there were island-shaped bone formation lesions. An immunohistochemical examination showed the expression of bone morphogenic protein-2 within tumor cells, which induce and stimulate bone formation. This finding may elucidate a possible mechanism of heterotopic bone formation.
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Adenocarcinoma/patologia , Neoplasias Pulmonares/patologia , Ossificação Heterotópica/patologia , Proteínas Morfogenéticas Ósseas/análise , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-IdadeRESUMO
We established a new lung cancer cell line, designated Y-ML-1B, from a lung cancer of a 70-year-old Japanese man with leukocytosis and thrombocytosis. Before surgical resection, the white blood cell and platelet counts were elevated to 34,400/mm3 and 668,000/mm3, respectively, and the granulocyte colony-stimulating factor (G-CSF) level in the serum was increased at 141 pg/mL. The primary tumor showed an undifferentiated morphology with large cells and induced extensive thickening of the pleura in the right hemithorax. The Y-ML-1B cells grow as a monolayer, with a doubling time of 19 hours, and are tumorigenic in nude mice, which showed a morphology similar to the primary tumor in xenografts. Analysis of the supernatant of cell culture medium of Y-ML-1B showed elevated levels of G-CSF and other cytokines such as interleukin (IL)-6, IL-8, and granulocyte-macrophage colony-stimulating factor (GM-CSF), consistent with the high levels detected in the patient's serum. Cytogenetic analysis revealed aneuploidy of greater than 56 in metaphases with many structural abnormalities. Mutation analysis of the tumor suppressor genes showed that Y-ML-1B is inactivated in TP53 and RASSF1A, but not in p14(ARF), p16(INK4A), or RB. Neither activating mutations of KRAS or NRAS nor amplification of MYC or MDM2 were detected. Y-ML-1B expressed N-cadherin but not E-cadherin. This newly established cell line might serve as a useful model for studying the molecular pathogenesis for large cell cancers of the lung which express high levels of cytokines.
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Carcinoma de Células Grandes/genética , Fator Estimulador de Colônias de Granulócitos/genética , Neoplasias Pulmonares/genética , Idoso , Animais , Sequência de Bases , Carcinoma de Células Grandes/patologia , Técnicas de Cultura de Células/métodos , Divisão Celular , Mapeamento Cromossômico , Primers do DNA , Humanos , Cariotipagem , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Nus , Proteínas de Neoplasias/genética , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proto-Oncogenes , Transplante Heterólogo , Células Tumorais CultivadasRESUMO
We report a case of a 40-year-old man with chylopericardium who developed purulent pericarditis caused by Salmonella enteritidis. Thoracoscopic pericardiotomy with debridement effectively controlled the pericardial infection.
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Derrame Pericárdico/complicações , Pericardite/etiologia , Infecções por Salmonella/complicações , Salmonella enteritidis , Adulto , Humanos , MasculinoRESUMO
PURPOSE: The aim of this study was to evaluate the technical and clinical efficacy and safety of CT-guided hookwire marking before video-assisted thoracoscopic surgery (VATS) for small pulmonary lesions. MATERIALS AND METHODS: This procedure was performed on 161 lesions in 154 patients (75 men and 79 women; median age, 62 years; age range 23-89 years). Medical records and images were reviewed, and the technical success rate, surgical success rate and complications were evaluated. Technical success was defined as successful hookwire marking at the target site without marker dropping before VATS. Surgical success was defined as negative surgical margins on pathological examination after VATS. RESULTS: There were 97 nodules and 64 ground-glass opacities, and their mean size was 9.8 mm (range 2-34). The technical success rate was 97.5% (157/161). In three of the four failed cases, another hookwire marker was placed, and in the remaining case, VATS was performed without a marker. The surgical success rate was 98.1% (158/161). In the three failed cases, the margin was positive, so lung lobectomy was performed in one case, and the other two cases were observed carefully. Complication rates were as follows: pneumothorax, 37.9% (61/161); focal intrapulmonary haemorrhage, 34.8% (58/139); haemoptysis, 0.6% (1/161); haemothorax, 0% (0/161); air embolism, 0.6% (1/161); dissemination, 0% (0/161); and death, 0% (0/161). CONCLUSION: CT-guided hookwire marking appears to be useful for VATS, but the procedure may, although rarely, cause severe complications such as air embolism.
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Marcadores Fiduciais , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Nódulo Pulmonar Solitário/patologia , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Torácica Vídeoassistida/instrumentação , Adulto , Idoso , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Aumento da Imagem/instrumentação , Neoplasias Pulmonares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Nódulo Pulmonar Solitário/diagnóstico por imagem , Cirurgia Torácica Vídeoassistida/métodos , Tomografia Computadorizada por Raios X/instrumentação , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto JovemRESUMO
Activating mutations of EGFR are found frequently in a subgroup of patients with non-small cell lung cancer (NSCLC) and are highly correlated with the response to gefitinib and erlotinib. In the present study, we searched for mutations of EGFR, HER2 and KRAS in 264 resected primary NSCLC from Japanese patients and determined whether there is a correlation between genetic alterations of these genes and clinicopathological factors, together with 85 tumors that we reported previously. EGFR mutations were found in 102 of the total 349 tumors, and seven tumors had two missense mutations. Reverse transcription-polymerase chain reaction of EGFR and subsequent subcloning analyses identified that the double mutations occurred in the same allele. Furthermore, in 202 NSCLC analyzed by Southern blotting, we identified 11 tumors with gene amplification of EGFR, with eight tumors containing a mutation in EGFR. Sequence analysis detected only weak or no signals of the wild-type allele in the eight tumors, strongly suggesting that the mutated allele was amplified selectively. These findings indicate that a dual genetic change of EGFR can occur in the same allele either with a possible second-hit mutation or with amplification, which may imply a more selective growth advantage in a cancer cell. Meanwhile, HER2 mutations and amplifications were found in six of 349 tumors and three of 202 tumors, respectively, and KRAS mutations in 21 of 349 tumors. Mutations of the EGFR and HER2 genes were more frequently found in female never or light-smoking patients with adenocarcinoma, and there were no tumors that had two or more mutations simultaneously among EGFR, HER2 and KRAS. The current study further demonstrates that a double genetic event in EGFR can occasionally occur in lung cancer, thus providing new clues for understanding the involvement of epidermal growth factor receptor signaling cascades in the pathogenesis of NSCLC.
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Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Amplificação de Genes , Neoplasias Pulmonares/genética , Mutação Puntual , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Genes erbB-2/genética , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Proteínas rasRESUMO
BACKGROUND: Lung carcinomas show frequent inactivation of the p53 tumor suppressor, which regulates an apoptotic pathway. The objective of the current study was to assess how the p53 apoptotic pathway is altered in nonsmall cell lung carcinoma (NSCLC), especially in tumors without p53 alterations. METHODS: p53, its upstream regulators (p14(ARF) and HDM2), and downstream effectors of the apoptotic pathway (BAX and BCL2) were studied in 118 NSCLC specimens. p53 was analyzed by single-stranded conformation polymorphism analysis covering exons 2-11 and by immunohistochemistry (IHC). p14(ARF) was analyzed by methylation-specific polymerase chain reaction and IHC. HDM2 was analyzed using Southern blot analysis and IHC. BAX and BCL2 were analyzed by IHC. Two other upstream regulators that regulate the stability of HDM2, PTEN and HAUSP, also were studied. RESULTS: Of 118 NSCLC specimens that were analyzed, p53 alterations were detected in 74 tumors (63%), p14(ARF) inactivation was detected in 53 tumors (45%), and overexpression of HDM2 was found in 31 tumors (26%), including 6 tumors with gene amplification. Although p53 inactivation and HDM2 overexpression were detected simultaneously, HDM2 gene amplification was observed only in tumor specimens without p53 mutations. IHC revealed PTEN down-regulation in 22 of 88 tumors (25%). HAUSP Northern blot analysis demonstrated several-fold differences in gene expression that did not correlate with p53 alterations. Of 118 NSCLC specimens, expression of BAX and BCL2 expression were detected in 46 tumors (39%) and 17 tumors (14%), respectively. Finally, ASPP1 and ASPP2, molecules involved in mediating the transcription function of p53, were not found to be aberrantly expressed when tested by Northern blot analysis. CONCLUSIONS: Overall, two or more p53 pathway components were found to be frequently altered in patients with NSCLC. Greater than 90% of the alterations were due to abnormalities of p53, p14(ARF), or HDM2. Therefore, the inactivation of one or more components of the p53 pathway appears to be a prerequisite for the development of most NSCLCs.
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Apoptose , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/fisiopatologia , Proteínas Proto-Oncogênicas/genética , Proteína Supressora de Tumor p14ARF/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias , Proteínas Nucleares , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2 , Proteína Supressora de Tumor p14ARF/metabolismo , Proteína Supressora de Tumor p14ARF/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteína Supressora de Tumor p53/farmacologia , Dedos de ZincoRESUMO
Activating mutations of RAS gene families have been found in a variety of human malignancies, including lung cancer, suggesting their dominant role in tumorigenesis. However, several studies have shown a frequent loss of the wild-type KRAS allele in the tumors of murine models and an inhibition of oncogenic phenotype in tumor cell lines by transfection of wild-type RAS, indicating that wild-type RAS may have oncosuppressive properties. To determine whether loss of wild-type KRAS is involved in the development of human lung cancer, we investigated the mutations of KRAS, NRAS and BRAF in 154 primary non-small cell lung cancers (NSCLCs) as well as 10 NSCLC cell lines that have been shown to have KRAS mutations. We also determined the loss of heterozygosity status of KRAS alleles in these tumors. We detected point mutations of KRAS in 11 (7%) of 154 NSCLCs, with 10 cases at codon 12 and 1 at codon 61, but no mutations of NRAS or BRAF were found. Using the laser capture microdissection technique, we confirmed that 9 of the 11 tumors and 7 of the 10 NSCLC cell lines retained the wild-type KRAS allele. Among the cell lines with heterozygosity of mutant and wild-type KRAS, all of the cell lines tested for expression were shown to express more mutated KRAS than wild-type mRNA, with higher amounts of KRAS protein also being expressed compared to the cell lines with a loss of wild-type KRAS allele. In addition, among 148 specimens available for immunohistochemical analysis, 113 (76%) showed positive staining of KRAS, indicating that the vast majority of NSCLCs continue to express wild-type KRAS. Our findings indicate that the wild-type KRAS allele is occasionally lost in human lung cancer, and that the oncogenic activation of mutant KRAS is more frequently associated with an overexpression of the mutant allele than with a loss of the wild-type allele in human NSCLC development.