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1.
J Eur Acad Dermatol Venereol ; 36(8): 1246-1255, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35426183

RESUMO

BACKGROUND: Staging systems for cutaneous squamous cell carcinoma (cSCC) produce inconsistent risk stratification. OBJECTIVE: The aim of this study was to identify further prognostic parameters for better stratification. METHODS: We retrospectively analysed the prognostic significance of clinicopathologic parameters of 230 patients who underwent primary excision of invasive cSCC of the head and neck (n = 115) and non-head and non-neck (n = 115) locations. In addition to known high-risk features, we analysed tumour nest shape, invasion pattern, lymphoid response pattern and tumour budding. RESULTS: On multivariable analysis, lymphovascular invasion (LVI) and high tumour budding predicted worse disease-specific survival, and ulceration, LVI and high tumour budding predicted worse overall survival. Only ulceration was independently associated with risk of nodal metastasis. CONCLUSION: High tumour budding, LVI and ulceration are independently associated with poor outcome in cSCC and may be used to refine cSCC prognostic stratification, which is crucial to optimize clinical decision and to identify patients who are more likely to benefit from more aggressive interventions or clinical trials.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Cutâneas , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço
3.
Theriogenology ; 149: 62-71, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32247214

RESUMO

For externally fertilizing fishes, interactions between male and female gametes have been shown to have remarkable impacts on sperm performance. Ovarian fluid (OF) and its ability to alter the swimming behavior of fish sperm makes it a determining factor of fertility. With the expansion of channel catfish (Ictalurus punctatus) ♀ × blue catfish (Ictalurus furcatus) ♂ hybrid aquaculture, it is essential to understand the impacts during fertilization and the magnitude such gametic interactions have on sperm performance and subsequent male fertility potential. This study was conducted to address the following: 1) activate blue catfish sperm with/without channel catfish OF to determine impacts on sperm performance and 2) assess if sperm behave differently when activated in the OF from individual females. Sperm (n = 4 males) were activated without OF (control) and with diluted OF from unique females (n = 6), creating 24 experimental crosses. Sperm motility (%), velocity (VCL), and longevity were analyzed using computer assisted sperm analyses software. With OF incorporated in the activation media, sperm velocity was significantly higher than the control at 10, 20, and 30 s post-activation. OF did not have an impact on motility for any females at 10 s and 20 s post-activation but became significantly higher than the control at 30 s. In all cases, OF treatments greatly increased longevity. Male × female interactions were highly significant, such that motility, velocity, and longevity were dependent on specific male-female pairs. This information shows that OF should be incorporated in aquatic media to simulate natural spawning conditions and accurately assess the fluid mechanics of sperm propulsion for each male. Additionally, there are mechanisms that drive gamete interactions that need to be explored further, which may improve selection of male-female pairs for in-vitro fertilization. On a broad scale, our results also help to shed light on the complexities of fertilization and fish reproduction overall, which may have implications for recruitment variability and recovery strategies of threatened and/or endangered freshwater species.


Assuntos
Fertilidade/fisiologia , Ictaluridae/fisiologia , Ovário/fisiologia , Reprodução/fisiologia , Espermatozoides/fisiologia , Animais , Aquicultura/métodos , Sobrevivência Celular/fisiologia , Líquido Extracelular/fisiologia , Feminino , Masculino , Motilidade dos Espermatozoides/fisiologia , Interações Espermatozoide-Óvulo/fisiologia
4.
J Dent Res ; 97(6): 635-644, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29489434

RESUMO

Oral squamous cell carcinoma (OSCC) is the most common type of oral cancer worldwide and in the United States. OSCC remains a major cause of morbidity and mortality in patients with head and neck cancers. Tobacco and alcohol consumption alone or with chewing betel nut are potential risk factors contributing to the high prevalence of OSCC. Multimodality therapies, including surgery, chemotherapy, biologic therapy, and radiotherapy, particularly intensity-modulated radiotherapy (IMRT), are the current treatments for OSCC patients. Despite recent advances in these treatment modalities, the overall survival remains poor over the past years. Recent data from whole-exome sequencing reveal that TP53 is commonly mutated in human papillomavirus-negative OSCC patients. Furthermore, these data stressed the importance of the TP53 gene in suppressing the development and progression of OSCC. Clinically, TP53 mutations are largely associated with poor survival and tumor resistance to radiotherapy and chemotherapy in OSCC patients, which makes the TP53 mutation status a potentially useful molecular marker prognostic and predictive of clinical response in these patients. Several forms of DNA damage have been shown to activate p53, including those generated by ionizing radiation and chemotherapy. The DNA damage stabilizes p53 in part via the DNA damage signaling pathway that involves sensor kinases, including ATM and ATR and effector kinases, such as Chk1/2 and Wee1, which leads to posttranscriptional regulation of a variety of genes involved in DNA repair, cell cycle control, apoptosis, and senescence. Here, we discuss the link of TP53 mutations with treatment outcome and survival in OSCC patients. We also provide evidence that small-molecule inhibitors of critical proteins that regulate DNA damage repair and replication stress during the cell cycle progression, as well as other molecules that restore wild-type p53 activity to mutant p53, can be exploited as novel therapeutic approaches for the treatment of OSCC patients bearing p53 mutant tumors.


Assuntos
Carcinoma de Células Escamosas/genética , Dano ao DNA/genética , Genes p53/genética , Neoplasias Bucais/genética , Mutação/genética , Carcinoma de Células Escamosas/terapia , Humanos , Neoplasias Bucais/terapia
5.
Cell Death Dis ; 6: e1678, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25766317

RESUMO

Treatment of head and neck squamous cell carcinoma, HNSCC, often requires multimodal therapy, including radiation therapy. The efficacy of radiotherapy in controlling locoregional recurrence, the most frequent cause of death from HNSCC, is critically important for patient survival. One potential biomarker to determine radioresistance is TP53 whose alterations are predictive of poor radiation response. DNA-damaging reactive oxygen species (ROS) are a by-product of ionizing radiation that lead to the activation of p53, transcription of p21(cip1/waf1) and, in the case of wild-type TP53 HNSCC cells, cause senescence. The expression of p21 and production of ROS have been associated with the induction of cellular senescence, but the intricate relationship between p21 and ROS and how they work together to induce senescence remains elusive. For the first time, we show that persistent exposure to low levels of the ROS, hydrogen peroxide, leads to the long-term expression of p21 in HNSCC cells with a partially functional TP53, resulting in senescence. We conclude that the level of ROS is crucial in initiating p53's transcription of p21 leading to senescence. It is p21's ability to sustain elevated levels of ROS, in turn, that allows for a long-term oxidative stress, and ensures an active p53-p21-ROS signaling loop. Our data offer a rationale to consider the use of either ROS inducing agents or therapies that increase p21 expression in combination with radiation as approaches in cancer therapy and emphasizes the importance of considering TP53 status when selecting a patient's treatment options.


Assuntos
Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Linhagem Celular Tumoral , Senescência Celular/fisiologia , Senescência Celular/efeitos da radiação , Humanos , Peróxido de Hidrogênio/farmacologia , Immunoblotting , Estresse Oxidativo/fisiologia , Fosforilação , Radiação Ionizante , Proteína Supressora de Tumor p53/genética
6.
AJNR Am J Neuroradiol ; 34(9): 1818-22, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23764725

RESUMO

BACKGROUND AND PURPOSE: Imaging correlates of genetic expression have been found for prognostic and predictive biomarkers of some malignant diseases, including breast and brain tumors. This study tests the hypothesis that imaging findings correlate with relevant genomic biomarkers in oral cavity squamous cell carcinoma. MATERIALS AND METHODS: Surplus frozen tissue from 27 untreated patients with oral cavity squamous cell carcinoma who underwent preoperative CT imaging was analyzed for gene expression. A team of neuroradiologists blinded to the genomic analysis results reviewed an extensive list of CT findings. The imaging correlated with genomic expression for cyclin D1, angiogenesis-related genes (vascular endothelial growth factor receptors and ligands), which relate to enhancement on the basis of other tumor types; and epidermal growth factor receptor, which may relate to proliferation and mass effect. RESULTS: Expression of vascular endothelial growth factor receptors 1 and 2 correlated with the enhancement of the primary tumor (P = .018 and P = .025, respectively), whereas the epidermal growth factor receptor correlated with mass effect (P = .03). Other exploratory correlations included epidermal growth factor receptor to perineural invasion (P = .05), and certain vascular endothelial growth factor receptors and ligands to mass effect (P = .03) and increased (P = .01) or decreased (P = .02) primary tumor size. CONCLUSIONS: We report that CT imaging correlates with gene expression in untreated oral cavity squamous cell carcinoma. Enhancement of the primary tumor and degree of mass effect correlate with relevant genomic biomarkers, which are also potential drug targets. Eventually, treatment decisions may be aided by combining imaging findings into meaningful phenotypes that relate directly to genomic biomarkers.


Assuntos
Proteínas Angiogênicas/genética , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/genética , Genes bcl-1/genética , Neoplasias Bucais/diagnóstico por imagem , Neoplasias Bucais/genética , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Predisposição Genética para Doença/genética , Genoma Humano/genética , Humanos , Masculino , Pessoa de Meia-Idade , Estatística como Assunto
7.
AJNR Am J Neuroradiol ; 34(8): 1637-42, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23471023

RESUMO

BACKGROUND AND PURPOSE: Criteria for detection of persistent nodal metastases in treated oropharyngeal tumors are sensitive but nonspecific, leading to unnecessary nodal dissections. Developing specific imaging criteria for persistent nodal metastases could improve diagnosis while decreasing patient morbidity. MATERIALS AND METHODS: Patients with oropharyngeal squamous cell carcinoma with nodal metastases treated by definitive radiation therapy and subsequent nodal dissection were retrospectively evaluated. One hundred thirty-eight patients had pre- and posttherapy contrast-enhanced CTs evaluated by radiologists blinded to the status of pathologically proved hemineck persistent nodal metastases. Composite scoring criteria for CT, combined from individual parameters, were compared with radiologists' opinions, previous multiparameter criteria, and outcome data. RESULTS: New low-attenuation areas and a lack of size change (<20% cross sectional area) were both highly specific for persistent nodal metastases (99%; P = .0004). Extranodal disease on pretherapy imaging was moderately specific (86%; P = .001). The CSC correctly placed 29 patients in a low-risk category compared with 14 by previously reported criteria and radiologist reports. With good second-rater reliability, the CSC cutoff values stratified patients at highest risk of persistent nodal metastases, thereby improving specificity while maintaining sensitivity. CONCLUSIONS: Comparing pre- and posttherapy examinations improves specificity by discriminating focal findings and size change compared with a single time point. The CSC can categorize the risk of persistent nodal metastases more accurately than previous CT methods. This finding has the potential to improve resource use and reduce surgical morbidity.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Linfonodos/diagnóstico por imagem , Neoplasias Orofaríngeas/diagnóstico por imagem , Neoplasias Orofaríngeas/radioterapia , Intensificação de Imagem Radiográfica/métodos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Carcinoma de Células Escamosas/epidemiologia , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Neoplasias Orofaríngeas/epidemiologia , Prevalência , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Texas/epidemiologia , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento
8.
AJNR Am J Neuroradiol ; 32(8): 1532-8, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21757532

RESUMO

BACKGROUND AND PURPOSE: Radiographic determination of viable disease in cervical adenopathy following RT for head and neck cancer can be challenging. The purpose of this study was to evaluate the utility of US, with or without FNA, in regard to the postradiotherapy effects on documented metastatic adenopathy in patients with oropharyngeal cancer. MATERIALS AND METHODS: This study included 133 patients with node-positive oropharyngeal cancer who were irradiated from 1998 to 2004. Sonographic evaluation was performed within 6 months of completion of radiation. Posttreatment US results were compared with pretreatment CT images and were recorded as the following: progression, suspicious, indeterminate, posttreatment change, or regression (positive) versus nonsuspicious or benign (negative). FNAC was classified as nondiagnostic, negative, indeterminate, or positive. Results of US and US-guided FNAC were correlated with findings at neck dissection and disease outcome. RESULTS: Of 203 sonographic examinations, 90% were technically feasible and yielded a nonequivocal imaging diagnosis. Of 87 US-guided FNAs, 71% yielded a nonequivocal tissue diagnosis. The PPV and NPV of initial posttreatment US were 11% and 97%. Sensitivity and specificity were 92% and 28%. The PPV and NPV of US-guided FNA were 33% and 95%, and the sensitivity and specificity were 75% and 74%. On serial sonographic surveillance, of 33 patients with nonsuspicious findings, only 1 (3%) had neck recurrence. Of 22 patients with questionable findings on CT and negative findings on US, none had a neck recurrence. CONCLUSIONS: In experienced hands, serial US is an inexpensive noninvasive reassuring follow-up strategy after definitive head and neck RT, even when CT findings are equivocal.


Assuntos
Pescoço/diagnóstico por imagem , Neoplasias Orofaríngeas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Feminino , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Pescoço/patologia , Neoplasias Orofaríngeas/patologia , Estudos Retrospectivos , Ultrassonografia
9.
Oncogene ; 30(28): 3163-73, 2011 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21383688

RESUMO

Although surgery and radiotherapy have been the standard treatment modalities for head and neck squamous cell carcinoma (HNSCC), the integration of cisplatin (CDDP)-based therapy has led to improvements in local and regional control of disease for patients. However, many trials show that only 10-20% of patients benefit from this treatment intensification, which can result in profound treatment-associated morbidity and mortality. Moreover, the marginal survival improvement suggests that CDDP resistance is an innate characteristic of HNSCC. To elucidate the biological mechanisms underpinning CDDP resistance in HNSCC, we utilized an experimental model of CDDP resistance in this disease. We first observed significant enhancements in local tumor growth and metastasis, as well as adverse survival, in CDDP-resistant (CR) tumors compared with sensitive tumors. To elucidate the molecular mechanisms of this phenotype, we undertook a systems biology-based approach utilizing high-throughput PCR arrays, and we identified a significant suppression of KiSS1 mRNA and protein expression in the CR cells, but no significant regions of genomic loss with array comparative genomic hybridization. Genetic suppression of KiSS1 in CDDP-sensitive cell lines rendered them CR, an observation that was mechanistically linked to alterations in glutathione S-transferase-π expression and function. We next confirmed that, in human HNSCC tumors, loss of KiSS1 expression was associated with metastatic human HNSCC tumors compared with non-metastatic tumors. Genetic reconstitution of KiSS1 in CR cells abrogated cellular migration and induced CDDP sensitivity. To confirm these findings in a murine model, either CR or KiSS1-transfected CR cells were studied in an orthotopic model of HNSCC, or survival studies revealed significant improvement in survival of the mice bearing CR-KiSS1 tumors. Mechanistically, alterations in apoptotic pathways and CDDP metabolism contributed to KiSS1-associated chemotherapy sensitization. These studies provided further direct evidence for the role of KiSS1 loss in biologically aggressive HNSCC and suggest potential targets for therapy in CR cancers.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Proteínas Supressoras de Tumor/metabolismo , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Glutationa Transferase/metabolismo , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Humanos , Kisspeptinas , Masculino , Camundongos , Metástase Neoplásica , Fenótipo , Supressão Genética/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética
10.
Spinal Cord ; 48(8): 639-44, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20125108

RESUMO

STUDY DESIGN: Prospective comparison of spinal cord injured (SCI) subjects and ambulatory subjects. OBJECTIVES: To determine the effects of the presence and level of SCI on heart rate recovery (HRR). SETTING: Outpatient SCI center. METHODS: HRR was determined in 63 SCI subjects (26 with tetraplegia, 22 with high-level paraplegia, 15 with low-level paraplegia) and 26 ambulatory subjects. To adjust for differences in heart rate reserve between groups (HR peak minus HR rest), HRR was also 'normalized' to a range of 1 at peak heart rate and to 0 at 8 min, and the shapes of HRR curves were compared. RESULTS: Although absolute HRR was similar between high- and low-level paraplegia, it was significantly more rapid in participants with paraplegia at 2, 5 and 8 min after exercise than in those with tetraplegia (39+/-14 vs 29+/-14 b.p.m., P<0.05; 51+/-14 vs 33+/-16 b.p.m., P<0.01 and 52+/-16 vs 36+/-17 b.p.m., P<0.01, respectively). HRR among ambulatory subjects was more rapid than among those with tetraplegia at all time points in recovery. However, when normalized for heart rate reserve, HRR was significantly more rapid in tetraplegic subjects (P<0.001 vs paraplegia and ambulatory subjects). CONCLUSION: In SCI, HRR is strongly associated with the peak exercise level and peak heart rate achieved during exercise testing.


Assuntos
Disreflexia Autonômica/fisiopatologia , Disreflexia Autonômica/terapia , Terapia por Exercício , Frequência Cardíaca/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/complicações , Adulto , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia
11.
Oncogene ; 29(14): 2047-59, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20101235

RESUMO

Head and neck squamous cell carcinoma (HNSCC) remains a significant public health problem, accounting for over 5% of all cancer-related deaths, and these deaths primarily result from metastatic disease. The molecular processes involved in HNSCC pathogenesis and progression are poorly understood, and here we present experimental evidence for a direct role of the cell surface receptor tyrosine kinase, TrkB, in HNSCC tumor progression. Using immunohistochemical analysis and transcriptional profiling of archival HNSCC tumor specimens, we found that TrkB and its secreted ligand, brain-derived neurotrophic factor (BDNF), are expresses in greater than 50% of human HNSCC tumors, but not in normal upper aerodigestive tract (UADT) epithelia. Studies with HNSCC cell lines reveal that in vitro stimulation with BDNF, the ligand for TrkB, upregulates the migration and invasion of HNSCC cells, and both transient and stable suppressions of TrkB result in significant abrogation of constitutive and ligand-mediated migration and invasion. Furthermore, enforced overexpression of TrkB results in altered expression of molecular mediators of epithelial-to-mesenchymal transition (EMT), including downregulation of E-cadherin and upregulation of Twist. Using an in vivo mouse model of HNSCC, we were able to show that downregulation of TrkB suppresses tumor growth. These results directly implicate TrkB in EMT and the invasive behavior of HNSCC, and correlate with the in vivo overexpression of TrkB in human HNSCC. Taken together, these data suggest that the TrkB receptor may be a critical component in the multi-step tumor progression of HNSCC, and may be an attractive target for much needed new therapies for this disease.


Assuntos
Carcinoma de Células Escamosas/patologia , Transformação Celular Neoplásica , Células Epiteliais/patologia , Neoplasias de Cabeça e Pescoço/patologia , Mesoderma/patologia , Receptor trkB/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Quimiotaxia , Progressão da Doença , Regulação para Baixo , Ativação Enzimática , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Ligantes , Masculino , Camundongos , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor trkB/deficiência , Receptor trkB/genética , Transdução de Sinais , Regulação para Cima
12.
Oncogene ; 27(25): 3527-38, 2008 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-18223693

RESUMO

Overexpression of S100A7 (psoriasin), a small calcium-binding protein, has been associated with the development of psoriasis and carcinomas in different types of epithelia, but its precise functions are still unknown. Using human tissue specimens, cultured cell lines, and a mouse model, we found that S100A7 is highly expressed in preinvasive, well-differentiated and early staged human squamous cell carcinoma of the oral cavity (SCCOC), but little or no expression was found in poorly differentiated, later-staged invasive tumors. Interestingly, our results showed that S100A7 inhibits both SCCOC cell proliferation in vitro and tumor growth/invasion in vivo. Furthermore, we demonstrated that S100A7 is associated with the beta-catenin complex, and inhibits beta-catenin signaling by targeting beta-catenin degradation via a noncanonical mechanism that is independent of GSK3beta-mediated phosphorylation. More importantly, our results also indicated that beta-catenin signaling negatively regulates S100A7 expression. Thus, this reciprocal negative regulation between S100A7 and beta-catenin signaling implies their important roles in tumor development and progression. Despite its high levels of expression in early stage SCCOC tumorigenesis, S100A7 actually inhibits SCCOC tumor growth/invasion as well as tumor progression. Downregulation of S100A7 in later stages of tumorigenesis increases beta-catenin signaling, leading to promotion of tumor growth and tumor progression.


Assuntos
Proteínas de Ligação ao Cálcio/metabolismo , Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Bucais/metabolismo , beta Catenina/metabolismo , Animais , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Progressão da Doença , Humanos , Camundongos , Modelos Biológicos , Neoplasias Bucais/patologia , Transplante de Neoplasias , Proteína A7 Ligante de Cálcio S100 , Proteínas S100 , Transdução de Sinais
13.
J Dent Res ; 87(1): 14-32, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18096889

RESUMO

The development of oral squamous cell carcinoma (OSCC) is a multistep process requiring the accumulation of multiple genetic alterations, influenced by a patient's genetic predisposition as well as by environmental influences, including tobacco, alcohol, chronic inflammation, and viral infection. Tumorigenic genetic alterations consist of two major types: tumor suppressor genes, which promote tumor development when inactivated; and oncogenes, which promote tumor development when activated. Tumor suppressor genes can be inactivated through genetic events such as mutation, loss of heterozygosity, or deletion, or by epigenetic modifications such as DNA methylation or chromatin remodeling. Oncogenes can be activated through overexpression due to gene amplification, increased transcription, or changes in structure due to mutations that lead to increased transforming activity. This review focuses on the molecular mechanisms of oral carcinogenesis and the use of biologic therapy to specifically target molecules altered in OSCC. The rapid progress that has been made in our understanding of the molecular alterations contributing to the development of OSCC is leading to improvements in the early diagnosis of tumors and the refinement of biologic treatments individualized to the specific characteristics of a patient's tumor.


Assuntos
Carcinoma de Células Escamosas/genética , Terapia Genética , Neoplasias Bucais/genética , Carcinoma de Células Escamosas/terapia , Meio Ambiente , Regulação da Expressão Gênica/genética , Genes Supressores de Tumor/fisiologia , Predisposição Genética para Doença , Humanos , Biologia Molecular , Neoplasias Bucais/terapia , Oncogenes/fisiologia
14.
Oncogene ; 26(10): 1385-97, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16953224

RESUMO

Constitutively activated nuclear factor-kappaB (NF-kappaB) has been associated with a variety of aggressive tumor types, including head and neck squamous cell carcinoma (HNSCC); however, the mechanism of its activation is not fully understood. Therefore, we investigated the molecular pathway that mediates constitutive activation of NF-kappaB in a series of HNSCC cell lines. We confirmed that NF-kappaB was constitutively active in all HNSCC cell lines (FaDu, LICR-LON-HN5 and SCC4) examined as indicated by DNA binding, immunocytochemical localization of p65, by NF-kappaB-dependent reporter gene expression and its inhibition by dominant-negative (DN)-inhibitory subunit of NF-kappaB (IkappaBalpha), the natural inhibitor of NF-kappaB. Constitutive NF-kappaB activation in HNSCC was found to be due to constitutive activation of IkappaBalpha kinase (IKK); and this correlated with constitutive expression of phosphorylated forms of IkappaBalpha and p65 proteins. All HNSCC showed the expression of p50, p52, p100 and receptor-interacting protein; all linked with NF-kappaB activation. The expression of constitutively active NF-kappaB in HNSCC is mediated through the tumor necrosis factor (TNF) signaling pathway, as NF-kappaB reporter activity was inhibited by DN-TNF receptor-associated death domain (TRADD), DN-TNF receptor-associated factor (TRAF)2, DN-receptor-interacting protein (RIP), DN-transforming growth factor-beta-activated kinase 1 (TAK1), DN-kappa-Ras, DN-AKT and DN-IKK but not by DN-TRAF5 or DN-TRAF6. Constitutive NF-kappaB activation was also associated with the autocrine expression of TNF, TNF receptors and receptor-activator of NF-kappaB and its ligand in HNSCC cells but not interleukin (IL)-1beta. All HNSCC cell lines expressed IL-6, a NF-kappaB-regulated gene product. Furthermore, treatment of HNSCC cells with anti-TNF antibody downregulated constitutively active NF-kappaB, and this was associated with inhibition of IL-6 expression and cell proliferation. Our results clearly demonstrate that constitutive activation of NF-kappaB is mediated through the TRADD-TRAF2-RIP-TAK1-IKK pathway, making TNF a novel target in the treatment of head and neck cancer.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , NF-kappa B/biossíntese , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Quinase I-kappa B/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Transdução de Sinais , Proteína de Domínio de Morte Associada a Receptor de TNF/metabolismo , Fator 2 Associado a Receptor de TNF/metabolismo , Fator de Transcrição RelA , Fatores de Crescimento Transformadores/metabolismo
15.
Oral Oncol ; 41(6): 580-8, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15975520

RESUMO

ICAM-5 (telencephalin) is an intercellular adhesion molecule reported to be expressed only in the somatodendritic membrane of telencephalic neurons. We recently identified high ICAM-5 expression in a cDNA array study of head and neck neoplasms with a propensity for perineural invasion. To determine the association of this gene in tumorigenesis and perineural invasion, we analyzed the expression and functional status of ICAM-5 mRNA transcripts in 30 different human cancer cell lines and 25 head and neck squamous carcinoma specimens by reverse-transcriptase polymerase chain reaction (cell lines and specimens) and in vitro functional assays (cell lines). ICAM-5 transcripts were detected in 28 (93%) of 30 cell lines derived from primary head and neck, colon, thyroid, cervical, pancreatic, skin, and adenoid cystic carcinomas. In cell lines, small interfering RNA blocked ICAM-5 expression and inhibited cell proliferation. Treatment with the phosphatidylinositol 3'-kinase (PBK) inhibitor LY294002 resulted in ICAM-5 down-regulation. In tissue specimens, none of the 25 histologically normal oral mucosal specimens had detectable ICAM-5 level, whereas 16 (64%) of the 25 matched primary squamous carcinomas showed expression. Carcinoma specimens high ICAM-5 expression had a high incidence of perineural invasion. Our study indicates that ICAM-5 may play a role in tumorigenesis and perineural invasion, most likely through the P13K/Akt-signaling pathway.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Moléculas de Adesão Celular , Transformação Celular Neoplásica/metabolismo , Cromonas/farmacologia , Inibidores Enzimáticos/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Morfolinas/farmacologia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Invasividade Neoplásica , Proteínas de Neoplasias/genética , Proteínas do Tecido Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Inibidores de Fosfoinositídeo-3 Quinase , RNA Mensageiro/genética , RNA Neoplásico/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Células Tumorais Cultivadas
16.
Br J Cancer ; 92(10): 1899-905, 2005 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-15870708

RESUMO

The phosphatidylinositol 3' kinase (PI3K)/phosphatase and tensin homologue deleted on chromosome ten/Akt pathway, which is a critical regulator of cell proliferation and survival, is mutated or activated in a wide variety of cancers. Akt appears to be a key central node in this pathway and thus is an attractive target for targeted molecular therapy. We demonstrated that Akt is highly phosphorylated in thyroid cancer cell lines and human thyroid cancer specimens, and hypothesised that KP372-1, an Akt inhibitor, would block signalling through the PI3K pathway and inhibit cell proliferation while inducing apoptosis of thyroid cancer cells. KP372-1 blocked signalling downstream of Akt in thyroid tumour cells, leading to inhibition of cell proliferation and increased apoptosis. As thyroid cancer consistently expresses phosphorylated Akt and KP372-1 effectively blocks Akt signalling, further preclinical evaluation of this compound for treatment of thyroid cancer is warranted.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/farmacologia , Tetrazóis/farmacologia , Neoplasias da Glândula Tireoide/patologia , Dano ao DNA , Humanos , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Células Tumorais Cultivadas
17.
Cancer ; 92(12): 3030-6, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11753980

RESUMO

INTRODUCTION: The presence of nodal metastases remains the most significant predictive factor for regional recurrence and survival in patients treated for squamous cell carcinoma of the head and neck. Survival rates are further decreased in patients with nodal metastases that have spread beyond the lymph node capsule, or extracapsular spread (ECS). To the authors' knowledge, this is the first report on the impact of ECS in a large series of patients treated for squamous cell carcinoma of the oral tongue (SCCOT) at a single institution using surgery as the primary treatment modality. METHODS: The authors retrospectively reviewed the medical records of all patients treated for SCCOT with resection of the primary and neck dissection at a single institution between 1980 and1995. RESULTS: Two hundred sixty-six patients were included in the study. Of that number, 146 patients (55%) were pathologically node-negative (pN0), 75 patients (28%) were pathologically node-positive (pN+) without ECS (pN+/ECS-), and 45 patients (17%) were pN+ with ECS (pN+/ECS+). The 5-year disease-specific and overall survival rates for pN0 patients were 88% and 75%; for pN+/ECS- patients, 65% and 50%; and 48% and 30% for pN+/ECS+ patients. The patterns of failure for the pN0, pN+/ECS- and, pN+/ECS+ groups showed overall recurrence rates of 19.8%, 34.2%, and 51.1% with regional failure rates of 11.5%, 19.2%, and 28.9%, respectively, and distant metastases rates of 3.3%, 8.2%, and 24.4%. CONCLUSIONS: ECS is the most significant predictor of both regional recurrence and development of distant metastasis accounting for decreased survival of patients with SCCOT in the current study. Therefore, intensive regional and systemic adjuvant therapy may be indicated for patients with ECS. Future studies should focus on identifying molecular mediators involved in ECS to determine targets for adjuvant therapies in this subset of patients.


Assuntos
Carcinoma de Células Escamosas/patologia , Metástase Linfática , Recidiva Local de Neoplasia , Neoplasias da Língua/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical , Metástase Neoplásica , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
18.
Cancer ; 92(9): 2364-73, 2001 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11745292

RESUMO

BACKGROUND: Thalidomide has been shown to have antiangiogenic effects in preclinical models as well as a significant antitumor effect in hematologic tumors such as multiple myeloma. The authors performed this Phase II study to determine the activity, toxicity profile, and antiangiogenic effect of thalidomide in patients with locoregionally recurrent or metastatic squamous cell carcinoma of the head and neck. METHODS: Twenty-one patients with recurrent or metastatic squamous cell carcinoma of the head and neck were treated with single-agent thalidomide. All patients had received radiation therapy, and most had undergone surgery (95%) and/or chemotherapy (90%). Thalidomide was initiated at 200 mg;3>daily and increased to a target dose of 1000 mg daily. Patients continued treatment until disease progression, unacceptable toxicity, or death occurred. RESULTS: All 21 patients eventually developed progressive disease. Median time to progression was 50 days (95% confidence interval, 28-70), with median overall survival time of 194 days (95% lower confidence boundary, 151), similar to the progression and survival times reported for this patient group with other agents. Thalidomide was generally well tolerated, with few patients experiencing Grades 3 to 4 toxicities. Serum vascular endothelial growth factor and basic fibroblast growth factor levels increased in six of seven patients, for whom paired serum samples were available and all of whom had progressive disease. CONCLUSIONS: In this heavily pretreated population of patients with advanced squamous cell carcinoma of the head and neck, thalidomide does not appear to have single-agent antitumor activity. Further evaluation of the mechanism of action of thalidomide is indicated. Potentially, future evaluations of thalidomide may be performed in combination with other antiangiogenic or cytotoxic agents in patients with earlier stage disease or in patients with minimal residual disease.


Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Talidomida/farmacologia , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Carcinoma de Células Escamosas/patologia , Progressão da Doença , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida , Talidomida/efeitos adversos , Resultado do Tratamento
19.
Otolaryngol Head Neck Surg ; 125(6): 645-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11743469

RESUMO

OBJECTIVE: To define risk factors for weight loss or dehydration during radiation therapy (RT). STUDY DESIGN AND SETTING: Retrospective chart review, academic tertiary care center. RESULTS: The incidence of severe weight loss during RT was 32.7%, the incidence of dehydration was 10.9%, and the rate of prophylactic feeding gastrostomy tube placement was 32%. The patients most likely to suffer severe weight loss included patients with tumor sites of nasopharynx and base of tongue, those treated with chemoradiation, and patients with severe pretreatment weight loss. Prophylactic feeding gastrostomy tube placement before RT significantly reduced the incidence of severe weight loss and hospitalization during RT. CONCLUSION: Severe weight loss and dehydration during RT for head and neck cancer is common. Prophylactic feeding gastrostomy tubes significantly reduce the incidence of severe weight loss and hospitalization for dehydration during RT when placed before onset of RT. Patients at risk for severe weight loss include those with severe pretreatment weight loss, tumors of the nasopharynx and base of tongue, or treatment with chemoradiation.


Assuntos
Desidratação/etiologia , Glote , Neoplasias de Cabeça e Pescoço/radioterapia , Hipofaringe , Neoplasias Laríngeas/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Orofaringe , Neoplasias Faríngeas/radioterapia , Radioterapia/efeitos adversos , Redução de Peso , Desidratação/classificação , Desidratação/epidemiologia , Desidratação/terapia , Nutrição Enteral/estatística & dados numéricos , Feminino , Gastrostomia/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença
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