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1.
PLoS Genet ; 11(4): e1005094, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25880434

RESUMO

In the United States, roughly 10% of the population is exposed daily to hazardous levels of noise in the workplace. Twin studies estimate heritability for noise-induced hearing loss (NIHL) of approximately 36%, and strain specific variation in sensitivity has been demonstrated in mice. Based upon the difficulties inherent to the study of NIHL in humans, we have turned to the study of this complex trait in mice. We exposed 5 week-old mice from the Hybrid Mouse Diversity Panel (HMDP) to a 10 kHz octave band noise at 108 dB for 2 hours and assessed the permanent threshold shift 2 weeks post exposure using frequency specific stimuli. These data were then used in a genome-wide association study (GWAS) using the Efficient Mixed Model Analysis (EMMA) to control for population structure. In this manuscript we describe our GWAS, with an emphasis on a significant peak for susceptibility to NIHL on chromosome 17 within a haplotype block containing NADPH oxidase-3 (Nox3). Our peak was detected after an 8 kHz tone burst stimulus. Nox3 mutants and heterozygotes were then tested to validate our GWAS. The mutants and heterozygotes demonstrated a greater susceptibility to NIHL specifically at 8 kHz both on measures of distortion product otoacoustic emissions (DPOAE) and on auditory brainstem response (ABR). We demonstrate that this sensitivity resides within the synaptic ribbons of the cochlea in the mutant animals specifically at 8 kHz. Our work is the first GWAS for NIHL in mice and elucidates the power of our approach to identify tonotopic genetic susceptibility to NIHL.


Assuntos
Perda Auditiva Provocada por Ruído/genética , NADPH Oxidases/genética , Animais , Potenciais Evocados Auditivos , Estudo de Associação Genômica Ampla , Perda Auditiva Provocada por Ruído/fisiopatologia , Heterozigoto , Camundongos , Camundongos Endogâmicos C57BL , Mutação
2.
Psychooncology ; 25(12): 1470-1476, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26387559

RESUMO

BACKGROUND: Prior survivorship research has largely focused on issues faced by survivors of childhood tumors, breast cancers, or hematologic malignancies. Relatively little is known about the needs of other prevalent survivor groups. Our aim was to identify the specific concerns of colorectal cancer (CRC) survivors in the key domains of physical functioning, psychological wellbeing, and social relationships. METHODS: We conducted focus groups with stage II and III CRC survivors who had completed their primary active anti-cancer treatments. Patients were asked to describe how their diagnosis and treatment impacted their lives, to outline deficiencies in the care that they received, and to suggest ways of addressing any unmet needs. A content analysis was subsequently conducted to identify major themes. RESULTS: Thirty CRC survivors participated in six focus groups. Individuals reported some degree of dissatisfaction with the amount and type of diagnostic and treatment information they received at their initial clinic visit. Distress from toxicities, such as peripheral neuropathy, was also common among the survivors. Similarly, the majority faced challenges adjusting to their lives and daily activities, especially in caring for their colostomy. Having survived CRC, many survivors expressed an interest in advocacy and health promotion of CRC. CONCLUSIONS: CRC survivors face many barriers after their cancer treatment. Issues with colostomy are unique to this survivor group. Interventions to improve CRC survivorship care should also incorporate opportunities for patient advocacy. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Sobreviventes de Câncer/psicologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/psicologia , Grupos Focais , Necessidades e Demandas de Serviços de Saúde , Qualidade de Vida/psicologia , Adaptação Psicológica , Adulto , Idoso , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/terapia , Colostomia/psicologia , Terapia Combinada/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equipe de Assistência ao Paciente , Satisfação do Paciente , Pesquisa Qualitativa , Apoio Social
3.
J Natl Compr Canc Netw ; 12(6): 863-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24925197

RESUMO

Dermatofibrosarcoma protuberans (DFSP) is an uncommon soft tissue tumor characterized by a relatively high risk of local recurrence and low risk of metastasis. The NCCN Guidelines for DFSP provide multidisciplinary recommendations on the management of patients with this rare disease. These NCCN Guidelines Insights highlight the addition of the Principles of Pathology section, which provides recommendations on the pathologic assessment of DFSP. Because DFSP can mimic other lesions, immunohistochemical studies are often required to establish diagnosis. Cytogenetic testing for the characteristic translocation t(17;22)(q22;q13) can also be valuable in the differential diagnosis of DFSP with other histologically similar tumors.


Assuntos
Dermatofibrossarcoma/genética , Diagnóstico Diferencial , Recidiva Local de Neoplasia/genética , Neoplasias Cutâneas/genética , Biomarcadores Tumorais , Dermatofibrossarcoma/diagnóstico , Dermatofibrossarcoma/patologia , Humanos , Metástase Neoplásica , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Translocação Genética
4.
J Natl Compr Canc Netw ; 12(5): 621-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24812131

RESUMO

The NCCN Guidelines for Melanoma provide multidisciplinary recommendations for the management of patients with melanoma. These NCCN Guidelines Insights highlight notable recent updates. Dabrafenib and trametinib, either as monotherapy (category 1) or combination therapy, have been added as systemic options for patients with unresectable metastatic melanoma harboring BRAF V600 mutations. Controversy continues regarding the value of adjuvant radiation for patients at high risk of nodal relapse. This is reflected in the category 2B designation to consider adjuvant radiation following lymphadenectomy for stage III melanoma with clinically positive nodes or recurrent disease.


Assuntos
Melanoma/terapia , Humanos
5.
J Natl Compr Canc Netw ; 12(5): 686-718, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24812137

RESUMO

Prostate cancer has surpassed lung cancer as the most common cancer in men in the United States. The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer based on clinical evidence and expert consensus. NCCN Panel guidance on treatment decisions for patients with localized disease is represented in this version. Significant updates for early disease include distinction between active surveillance and observation, a new section on principles of imaging, and revisions to radiation recommendations. The full version of these guidelines, including treatment of patients with advanced disease, can be found online at the NCCN website.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Humanos , Masculino
6.
J Natl Compr Canc Netw ; 12(3): 410-24, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24616545

RESUMO

Merkel cell carcinoma is a rare, aggressive cutaneous tumor that combines the local recurrence rates of infiltrative nonmelanoma skin cancer with the regional and distant metastatic rates of thick melanoma. The NCCN Guidelines for Merkel Cell Carcinoma provide recommendations on the diagnosis and management of this aggressive disease based on clinical evidence and expert consensus. This version includes revisions regarding the use of PET/CT imaging and the addition of a new section on the principles of pathology to provide guidance on the analysis, interpretation, and reporting of pathology results.


Assuntos
Carcinoma de Célula de Merkel/diagnóstico , Carcinoma de Célula de Merkel/terapia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Humanos
7.
J Natl Compr Canc Netw ; 12(11): 1517-23, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25361798

RESUMO

The NCCN Guidelines for Central Nervous System Cancers provide multidisciplinary recommendations for the clinical management of patients with cancers of the central nervous system. These NCCN Guidelines Insights highlight recent updates regarding the management of metastatic brain tumors using radiation therapy. Use of stereotactic radiosurgery (SRS) is no longer limited to patients with 3 or fewer lesions, because data suggest that total disease burden, rather than number of lesions, is predictive of survival benefits associated with the technique. SRS is increasingly becoming an integral part of management of patients with controlled, low-volume brain metastases.


Assuntos
Neoplasias do Sistema Nervoso Central/secundário , Neoplasias do Sistema Nervoso Central/cirurgia , Humanos , Radiocirurgia/métodos
8.
J Natl Compr Canc Netw ; 12(9): 1211-9; quiz 1219, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25190691

RESUMO

The NCCN Guidelines for Prostate Cancer Early Detection provide recommendations for men choosing to participate in an early detection program for prostate cancer. These NCCN Guidelines Insights highlight notable recent updates. Overall, the 2014 update represents a more streamlined and concise set of recommendations. The panel stratified the age ranges at which initiating testing for prostate cancer should be considered. Indications for biopsy include both a cutpoint and the use of multiple risk variables in combination. In addition to other biomarkers of specificity, the Prostate Health Index has been included to aid biopsy decisions in certain men, given recent FDA approvals.


Assuntos
Detecção Precoce de Câncer , Neoplasias da Próstata/diagnóstico , Fatores Etários , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Humanos , Masculino , Vigilância da População , Neoplasias da Próstata/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
J Natl Compr Canc Netw ; 11(10): 1266-90, 2013 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-24142827

RESUMO

Febrile neutropenia, a common side effect of myelosuppressive chemotherapy in patients with cancer, can result in prolonged hospitalization and broad-spectrum antibiotic use, often prompting treatment delays or dose reductions of drug regimens. Prophylactic use of myeloid growth factors (mainly the colony-stimulating factors filgrastim and pegfilgrastim) in patients of heightened risk can reduce the severity and duration of febrile neutropenia. The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Myeloid Growth Factors provide recommendations on the use of these agents mainly in the oncology setting based on clinical evidence and expert consensus. This version includes revisions surrounding the issue of timing of pegfilgrastim administration. It also includes new sections on tbo-filgrastim, a recently approved agent that is biologically similar to filgrastim, and the role of myeloid growth factors in the hematopoietic cell transplant setting.


Assuntos
Neutropenia Febril Induzida por Quimioterapia/tratamento farmacológico , Fatores Estimuladores de Colônias/uso terapêutico , Neutropenia Febril Induzida por Quimioterapia/prevenção & controle , Doença Crônica , Fatores Estimuladores de Colônias/administração & dosagem , Fatores Estimuladores de Colônias/efeitos adversos , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas , Humanos , Neutropenia/tratamento farmacológico , Neutropenia/etiologia , Pré-Medicação , Resultado do Tratamento
10.
J Natl Compr Canc Netw ; 11(9): 1114-51, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-24029126

RESUMO

Primary and metastatic tumors of the central nervous system are a heterogeneous group of neoplasms with varied outcomes and management strategies. Recently, improved survival observed in 2 randomized clinical trials established combined chemotherapy and radiation as the new standard for treating patients with pure or mixed anaplastic oligodendroglioma harboring the 1p/19q codeletion. For metastatic disease, increasing evidence supports the efficacy of stereotactic radiosurgery in treating patients with multiple metastatic lesions but low overall tumor volume. These guidelines provide recommendations on the diagnosis and management of this group of diseases based on clinical evidence and panel consensus. This version includes expert advice on the management of low-grade infiltrative astrocytomas, oligodendrogliomas, anaplastic gliomas, glioblastomas, medulloblastomas, supratentorial primitive neuroectodermal tumors, and brain metastases. The full online version, available at NCCN. org, contains recommendations on additional subtypes.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/terapia , Humanos
11.
J Natl Compr Canc Netw ; 11(12): 1471-9, 2013 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-24335682

RESUMO

The NCCN Guidelines for Prostate Cancer provide multidisciplinary recommendations on the clinical management of patients with prostate cancer. This report highlights notable recent updates. Radium-223 dichloride is a first-in-class radiopharmaceutical that recently received approval for the treatment of patients with symptomatic bone metastases and no known visceral disease. It received a category 1 recommendation as both a first-line and second-line option. The NCCN Prostate Cancer Panel also revised recommendations on the choice of intermittent or continuous androgen deprivation therapy based on recent phase III clinical data comparing the 2 strategies in the nonmetastatic and metastatic settings.


Assuntos
Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Neoplasias Ósseas/secundário , Neoplasias Ósseas/terapia , Humanos , Masculino , Estadiamento de Neoplasias , Radioisótopos/uso terapêutico , Rádio (Elemento)/uso terapêutico , Recidiva
12.
J Natl Compr Canc Netw ; 11(5): 594-615, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23667209

RESUMO

Squamous cell carcinoma of the penis represents approximately 0.5% of all cancers among men in the United States and other developed countries. Although rare, it is associated with significant disfigurement, and only half of the patients survive beyond 5 years. Proper evaluation of both the primary lesion and lymph nodes is critical, because nodal involvement is the most important factor of survival. The NCCN Clinical Practice Guidelines in Oncology for Penile Cancer provide recommendations on the diagnosis and management of this devastating disease based on evidence and expert consensus.


Assuntos
Neoplasias Penianas/diagnóstico , Neoplasias Penianas/terapia , Seguimentos , Humanos , Masculino , Metástase Neoplásica , Estadiamento de Neoplasias , Recidiva , Fatores de Risco
13.
J Natl Compr Canc Netw ; 11(4): 395-407, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23584343

RESUMO

The NCCN Guidelines for Melanoma provide multidisciplinary recommendations on the clinical management of patients with melanoma. This NCCN Guidelines Insights report highlights notable recent updates. Foremost of these is the exciting addition of the novel agents ipilimumab and vemurafenib for treatment of advanced melanoma. The NCCN panel also included imatinib as a treatment for KIT-mutated tumors and pegylated interferon alfa-2b as an option for adjuvant therapy. Also important are revisions to the initial stratification of early-stage lesions based on the risk of sentinel lymph node metastases, and revised recommendations on the use of sentinel lymph node biopsy for low-risk groups. Finally, the NCCN panel reached clinical consensus on clarifying the role of imaging in the workup of patients with melanoma.


Assuntos
Melanoma/terapia , Guias de Prática Clínica como Assunto , Neoplasias Cutâneas/terapia , Algoritmos , Quimioterapia Adjuvante , Assistência Integral à Saúde/organização & administração , Progressão da Doença , Educação Médica Continuada/legislação & jurisprudência , Humanos , Interferons/uso terapêutico , Oncologia/organização & administração , Melanoma/diagnóstico , Melanoma/patologia , Biópsia de Linfonodo Sentinela/educação , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Sociedades Médicas/legislação & jurisprudência , Sociedades Médicas/organização & administração , Terapias em Estudo/métodos
14.
J Natl Compr Canc Netw ; 11(4): 446-75, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23584347

RESUMO

Bladder cancer is the fourth most common cancer in the United States. Urothelial carcinoma that originates from the urinary bladder is the most common subtype. These NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) provide recommendations on the diagnosis and management of non-muscle-invasive and muscle-invasive urothelial carcinoma of the bladder. This version of the guidelines provides extensive reorganization and updates on the principles of chemotherapy management.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/terapia , Neoplasias da Bexiga Urinária/terapia , Administração Intravesical , Algoritmos , Carcinoma/tratamento farmacológico , Carcinoma/epidemiologia , Carcinoma/patologia , Cistectomia/métodos , Cistectomia/estatística & dados numéricos , Feminino , Humanos , Masculino , Neoplasias Musculares/tratamento farmacológico , Neoplasias Musculares/epidemiologia , Neoplasias Musculares/secundário , Terapia Neoadjuvante/métodos , Invasividade Neoplásica , Estadiamento de Neoplasias/métodos , Tratamentos com Preservação do Órgão/métodos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/epidemiologia , Neoplasias da Bexiga Urinária/patologia , Urotélio/patologia
16.
J Natl Compr Canc Netw ; 10(9): 1081-7, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22956807

RESUMO

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Prostate Cancer provide multidisciplinary recommendations for the clinical management of patients with prostate cancer. These NCCN Guidelines Insights highlight notable recent updates. Abiraterone acetate is a first-in-class hormonal agent that represents a new standard of care for patients with metastatic castration-recurrent prostate cancer who have previously received docetaxel (category 1 recommendation). Abiraterone acetate also received category 2B recommendations in the prechemotherapy setting for asymptomatic patients or symptomatic patients who are not candidates for docetaxel. The NCCN Prostate Cancer Panel also added new indications for existing agents, including the option of sipuleucel-T as second-line therapy. In addition, brachytherapy in combination with external beam radiation therapy with or without androgen deprivation therapy is now an alternative for patients with high-risk localized tumors or locally advanced disease.


Assuntos
Neoplasias da Próstata/terapia , Acetato de Abiraterona , Antagonistas de Androgênios/uso terapêutico , Androstadienos/uso terapêutico , Antineoplásicos/uso terapêutico , Braquiterapia , Docetaxel , Humanos , Masculino , Orquiectomia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Taxoides/uso terapêutico , Extratos de Tecidos/uso terapêutico
17.
Aust N Z J Obstet Gynaecol ; 52(2): 195-203, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22188386

RESUMO

BACKGROUND: The Australasian Maternity Outcomes Surveillance System (AMOSS) conducts surveillance and research of rare and serious conditions in pregnancy. This multi-centre population health study is considered low risk with minimal ethical impact. OBJECTIVE: To describe the ethics/governance review pathway undertaken by AMOSS. METHOD: Prospective, descriptive study during 2009-2011 of the governance/ethical review processes required to gain approval for Australian and New Zealand (ANZ) maternity units with more than 50 births per year (n = 303) to participate in AMOSS. RESULTS: Review processes ranged from a single application for 24 NZ sites, a single application for eligible hospitals in two Australian states, full Health Research Ethics Committee (HREC) applications for individual hospitals, through simple letters of support. As of September 2011, 46 full/expedited ethics applications, 131 site governance applications and 136 letters of support requests were made over 33 months, involving an estimated 3261 hours by AMOSS staff/investigators, and an associated resource burden by participating sites, to obtain approval to receive nonidentifiable data from 291 hospitals. CONCLUSION: The AMOSS research system provides an important resource to enhance knowledge of conditions that cause rare and serious maternal morbidity. Yet the highly variable ethical approval processes required to implement this study have been excessively repetitive and burdensome. This process jeopardises timely, efficient research project implementation, without corresponding benefits to research participants. The resource burden to establish research governance for AMOSS confirms the urgent need for the Harmonisation of Multi-centre Ethical Review (HoMER) to further streamline ethics/governance review processes for multi-centre research.


Assuntos
Pesquisas sobre Atenção à Saúde/ética , Maternidades/ética , Auditoria Médica/ética , Adulto , Austrália , Revisão Ética , Comitês de Ética em Pesquisa , Ética em Pesquisa , Feminino , Humanos , Mortalidade Materna , Estudos Multicêntricos como Assunto/ética , Nova Zelândia , Gravidez , Estudos Prospectivos , Risco
18.
Cancer Causes Control ; 22(12): 1659-68, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21971815

RESUMO

BACKGROUND: Our aims were to determine clinical factors associated with colorectal cancer (CRC) screening and to evaluate the relative role of patient contact with physicians and the quality of these patient-physician interactions in affecting screening. METHODS: Screening-eligible patients were identified from the Health Information National Trends Survey. Determinants of CRC screening were assessed with logistic regression, and a joint effects model that considered the frequency and quality of contact with physicians was developed to explore their influence on screening. RESULTS: There were 4,615 respondents of whom only 66% reported receiving CRC screening. Older age, personal history of non-CRC, family history of any cancer, high-income earners, individuals who visited their physicians ≥5 times per year, and those who rated the interactions with their physicians highly were more likely to be screened (all p < 0.05). The joint effects model revealed that quality rather than frequency of physician contact was a stronger predictor of CRC screening, but the odds of screening was highest for those who experienced both frequent and high-quality interactions with their physicians. CONCLUSIONS: Contact with physicians and the quality of this interaction are associated with screening behavior. Interventions to improve these provider-related factors may promote CRC screening.


Assuntos
Neoplasias Colorretais/prevenção & controle , Programas de Rastreamento/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Relações Médico-Paciente , Idoso , Detecção Precoce de Câncer/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Aust N Z J Obstet Gynaecol ; 50(3): 280-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20618248

RESUMO

OBJECTIVE: To compare a strategy of two cycles of intrauterine insemination with controlled ovarian hyperstimulation (IUI/COH) vs one in vitro fertilisation (IVF) treatment programme (one fresh plus associated frozen embryo cycles) in couples presenting with unexplained, mild male or mild female subfertility. METHODS: A retrospective cohort design was used and analysed according to intention-to-treat principles. A total of 272 couples underwent an intended course of two cycles of IUI/COH and 176 couples underwent one IVF treatment programme. RESULTS: The cumulative live birth rate (CLBR) per couple for the IUI/COH group was 27.6% compared to 39.2% for the IVF group (P = 0.01). The mean time to pregnancy was 69 days in the IUI/COH group compared to 44 days in the IVF group (P = 0.02). The IVF programme was costlier, with an incremental cost-effectiveness ratio for an additional live birth in the range of $39,637-$46,325. The multiple delivery rate was 13.3% in the IUI/COH group compared to 10.1% in the IVF group (P = 0.55). One set of triplets and one set of quadruplets followed IUI/COH treatment. CONCLUSIONS: One IVF treatment programme was more effective, but costlier than an intended course of two cycles of IUI/COH. With consistently higher success rates, shorter times to pregnancy and a trend to less higher order multiple pregnancies, this study supports the view that IVF is now potentially safer and more clinically effective than IUI/COH as a first-line therapy for subfertility.


Assuntos
Fertilização in vitro , Infertilidade/terapia , Inseminação Artificial , Adulto , Coeficiente de Natalidade , Estudos de Coortes , Análise Custo-Benefício , Feminino , Fertilização in vitro/economia , Humanos , Inseminação Artificial/economia , Masculino , Indução da Ovulação/economia , Gravidez , Estudos Retrospectivos
20.
Cancer Res ; 67(10): 4827-33, 2007 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-17510412

RESUMO

Stem cells have been isolated by their ability to efflux Hoechst 33342 dye and are referred to as the "side population" (SP). In this study, we used flow cytometry and Hoechst 33342 dye efflux assay to isolate and characterize SP cells from six human lung cancer cell lines (H460, H23, HTB-58, A549, H441, and H2170). Nonobese diabetic/severe combined immunodeficiency xenograft experiments showed that SP cells were enriched in tumor-initiating capability compared with non-SP cells. Matrigel invasion assay showed that SP cells also have higher potential for invasiveness. Further characterization of this SP phenotype revealed several stem cell properties. We found evidence for repopulating ability by SP to regenerate a population resembling the original population. SP displayed elevated expression of ABCG2 as well as other ATP-binding cassette transporters and showed resistance to multiple chemotherapeutic drugs. Human telomerase reverse transcriptase expression was higher in the SP, suggesting that this fraction may represent a reservoir with unlimited proliferative potential for generating cancer cells. mRNA levels of minichromosome maintenance (MCM) 7, a member of the MCM family of proteins critical to the DNA replication complex, were lower in SP cells, suggesting that a majority of the SP fraction was in the G(0) quiescent state. Sixteen clinical lung cancer samples also displayed a smaller but persistent SP population. These findings indicate that SP is an enriched source of lung tumor-initiating cells with stem cell properties and may be an important target for effective therapy and a useful tool to investigate the tumorigenic process.


Assuntos
Neoplasias Pulmonares/patologia , Células-Tronco Neoplásicas/patologia , Transportadores de Cassetes de Ligação de ATP/biossíntese , Antígenos CD34/biossíntese , Antígeno CD24/biossíntese , Proteínas de Ciclo Celular/biossíntese , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Humanos , Receptores de Hialuronatos/biossíntese , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Componente 7 do Complexo de Manutenção de Minicromossomo , Invasividade Neoplásica , Células-Tronco Neoplásicas/metabolismo , Proteínas Nucleares/biossíntese , Proteínas Nucleares/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Telomerase/metabolismo , Regulação para Cima
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