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1.
Int J Surg Case Rep ; 120: 109884, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38875830

RESUMO

INTRODUCTION: Percutaneous endoscopic lumbar discectomy (PELD) is increasingly being utilized to treat patients with lumbar disc herniation. PELD is unique in that it uses a single working port endoscope with constant irrigation of the surgical field to visualize pathology. The current report is of a case of postoperative epidural irrigation fluid accumulation presenting as peripherally enhancing epidural lesions, masking an underlying re-herniation. PRESENTATION OF CASE: A patient with a Lumbar 5-Sacral 1 level disc herniation presenting with radiculopathy was treated using PELD. Following the operation, the patient experienced recurrent pain, prompting a repeat MRI of the lumbar spine. Multiple ring-enhancing lesions within the epidural space were observed, creating diagnostic dilemmas. The differential diagnoses included epidural abscess, pseudomeningocele from unintended durotomy, epidural hematoma, or trapped epidural fluid collection presenting as a pseudocyst with or without recurrent disc herniation. A repeat endoscopic discectomy was performed to confirm the diagnosis of pseudocyst, revealing a recurrent disc herniation. DISCUSSION: Pseudocysts are not an uncommon complication of PELD, typically believed to be due to an inflammatory response to disc fragments. However, in this case, the epidural fluid collection was likely the result of trapped irrigation fluid from continuous irrigation during the procedure, which masked an underlying re-herniation on imaging. CONCLUSION: With the increasing utilization of PELD, it is important to acknowledge unique complications such as fluid accumulation from irrigation within the epidural space. Fluid accumulation can lead to contrast-enhancing pseudocyst formation, which can theoretically lead to mass effect or increased intracranial and intraspinal pressure and may mask additional underlying pathology.

2.
J Integr Complement Med ; 30(7): 691-697, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38416862

RESUMO

Objective: To evaluate the extent to which personal well-being may be associated with empathy, while controlling for potential confounders. Settings/Location: Residency programs throughout the United States. Subjects: A total of 407 medical residents from residencies including general medicine, surgery, specialized and diagnostic medicine participated in this study. Outcome Measures: Well-being was measured using the modified existential well-being subscale of the spiritual well-being scale. Empathy was measured using the Jefferson Scale of Empathy. Results: Well-being was found to be positively correlated with empathy when adjusted for possible confounders (p < 0.001). In addition to well-being, other factors noted to be statistically significant contributors to higher empathy scores while controlling for the others included age, gender, year in residency, specialty, and work-hours (p < 0.05 for each). After controlling for these factors, a resident's year in residency was not found to be a statistically significant contributor to empathy score. Conclusions: In this study, well-being was associated with empathy in medical and surgical residents. Empathy is a fundamental component of physician competency, and its development is an essential aspect of medical training. These findings suggest that efforts to increase well-being may promote empathy among medical residents.


Assuntos
Empatia , Internato e Residência , Humanos , Masculino , Feminino , Estudos Transversais , Adulto , Inquéritos e Questionários , Estados Unidos , Médicos/psicologia
3.
J Neurosurg Spine ; : 1-10, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35364569

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the safety of oligodendrocyte progenitor cells (LCTOPC1) derived from human pluripotent stem cells administered between 7 and 14 days postinjury to patients with T3 to T11 neurologically complete spinal cord injury (SCI). The rationale for this first-in-human trial was based on evidence that administration of LCTOPC1 supports survival and potential repair of key cellular components and architecture at the SCI site. METHODS: This study was a multisite, open-label, single-arm interventional clinical trial. Participants (n = 5) received a single intraparenchymal injection of 2 × 106 LCTOPC1 caudal to the epicenter of injury using a syringe positioning device. Immunosuppression with tacrolimus was administered for a total of 60 days. Participants were followed with annual in-person examinations and MRI for 5 years at the time of this report and will be followed with annual telephone questionnaires for 6 to 15 years postinjection. The primary endpoint was safety, as measured by the frequency and severity of adverse events related to the LCTOPC1 injection, the injection procedure, and/or the concomitant immunosuppression administered. The secondary endpoint was neurological function as measured by sensory scores and lower-extremity motor scores as measured by the International Standards for Neurological Classification of Spinal Cord Injury examinations. RESULTS: No unanticipated serious adverse events related to LCTOPC1 have been reported with 98% follow-up of participants (49 of 50 annual visits) through the first 10 years of the clinical trial. There was no evidence of neurological decline, enlarging masses, further spinal cord damage, or syrinx formation. MRI results during the long-term follow-up period in patients administered LCTOPC1 cells showed that 80% of patients demonstrated T2 signal changes consistent with the formation of a tissue matrix at the injury site. CONCLUSIONS: This study provides crucial first-in-human safety data supporting the pursuit of future human embryonic stem cell-derived therapies. While we cannot exclude the possibility of future adverse events, the experience in this trial provides evidence that this cell type can be well tolerated by patients, with an event-free period of up to 10 years. Based on the safety profile of LCTOPC1 obtained in this study, a cervical dose escalation trial was initiated (NCT02302157).

4.
Int J Surg Case Rep ; 91: 106789, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35093704

RESUMO

INTRODUCTION AND IMPORTANCE: Pseudomeningocele formation from incidental durotomy is a known risk in spine surgery. We present a case of incidental durotomy leading to anterior neck pseudomeningocele, compressing the carotid body (CB) resulting in syncopal episodes. To our knowledge, this is the first case report implicating syncopal episodes to CB compression via a pseudomeningocele. CASE PRESENTATION: A mid sixty-year-old patient with history of obesity, hypertension, and diabetes presented with gait impairment and hand weakness. Ossification of posterior longitudinal ligament (OPLL) was diagnosed with computed tomography imaging (CT) and magnetic resonance imaging (MRI). Elective surgery was completed with an anterior and posterior approach for decompression and fusion. Hospital course (San Jose, CA, USA) was complicated by respiratory depression and incomplete tetraplegia. On post-operative day (POD) six, CT revealed anterolateral soft tissue neck swelling; subsequent CT and MRI showed fluid collection expansion, with associated syncopal episodes on POD thirty-nine. Despite interventional radiology drainage, the fluid collection and symptoms returned five days later. The patient ultimately underwent durotomy revision and repair with muscle patch. CLINICAL DISCUSSION: This case highlights the challenges in managing anterior cervical dural tears resulting in pseudomeningocele. Risk factors include anterior cervical corpectomy and decompression, as well as an underlying diagnosis of OPLL. Untreated dural tears may develop into pseudomeningoceles which can contribute to life-threatening outcomes. CONCLUSION: This case report presents the serious consequences of incidental durotomy, the unique post-surgical complication of syncope due to compression of the CB from a pseudomeningocele, and the challenges of managing a persistent pseudomeningocele.

5.
Elife ; 102021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783309

RESUMO

Background: Predicting neurological recovery after spinal cord injury (SCI) is challenging. Using topological data analysis, we have previously shown that mean arterial pressure (MAP) during SCI surgery predicts long-term functional recovery in rodent models, motivating the present multicenter study in patients. Methods: Intra-operative monitoring records and neurological outcome data were extracted (n = 118 patients). We built a similarity network of patients from a low-dimensional space embedded using a non-linear algorithm, Isomap, and ensured topological extraction using persistent homology metrics. Confirmatory analysis was conducted through regression methods. Results: Network analysis suggested that time outside of an optimum MAP range (hypotension or hypertension) during surgery was associated with lower likelihood of neurological recovery at hospital discharge. Logistic and LASSO (least absolute shrinkage and selection operator) regression confirmed these findings, revealing an optimal MAP range of 76-[104-117] mmHg associated with neurological recovery. Conclusions: We show that deviation from this optimal MAP range during SCI surgery predicts lower probability of neurological recovery and suggest new targets for therapeutic intervention. Funding: NIH/NINDS: R01NS088475 (ARF); R01NS122888 (ARF); UH3NS106899 (ARF); Department of Veterans Affairs: 1I01RX002245 (ARF), I01RX002787 (ARF); Wings for Life Foundation (ATE, ARF); Craig H. Neilsen Foundation (ARF); and DOD: SC150198 (MSB); SC190233 (MSB).


Spinal cord injury is a devastating condition that involves damage to the nerve fibers connecting the brain with the spinal cord, often leading to permanent changes in strength, sensation and body functions, and in severe cases paralysis. Scientists around the world work hard to find ways to treat or even repair spinal cord injuries but few patients with complete immediate paralysis recover fully. Immediate paralysis is caused by direct damage to neurons and their extension in the spinal cord. Previous research has shown that blood pressure regulation may be key in saving these damaged neurons, as spinal cord injuries can break the communication between nerves that is involved in controlling blood pressure. This can lead to a vicious cycle of dysregulation of blood pressure and limit the supply of blood and oxygen to the damaged spinal cord tissue, exacerbating the death of spinal neurons. Management of blood pressure is therefore a key target for spinal cord injury care, but so far, the precise thresholds to enable neurons to recover are poorly understood. To find out more, Torres-Espin, Haefeli et al. used machine learning software to analyze previously recorded blood pressure and heart rate data obtained from 118 patients that underwent spinal cord surgery after acute spinal cord injury. The analyses revealed that patients who suffered from either low or high blood pressure during surgery had poorer prospects of recovery. Statistical models confirming these findings showed that the optimal blood pressure range to ensure recovery lies between 76 to 104-117 mmHg. Any deviation from this narrow window would dramatically worsen the ability to recover. These findings suggests that dysregulated blood pressure during surgery affects to odds of recovery in patients with a spinal cord injury. Torres-Espin, Haefeli et al. provide specific information that could improve current clinical practice in trauma centers. In the future, such machine learning tools and models could help develop real-time models that could predict the likelihood of a patient's recovery following spinal cord injury and related neurological conditions.


Assuntos
Pressão Arterial , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Medula Espinal/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Humanos , Pessoa de Meia-Idade , Monitorização Intraoperatória , Estudos Retrospectivos
6.
Cureus ; 13(5): e14835, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-34104585

RESUMO

The intrathecal drug delivery system (IDDS) is successfully utilized for the treatment of chronic pain conditions; however, they are associated with complications related to human error and system failure. A case report is presented of a patient with opioid withdrawal (OW) secondary to assumed catheter microfracture. Interrogation of the IDDS allowed for the collection of pre- and post-treatment/stabilization cerebrospinal fluid (CSF), which is used to investigate the possible physiological determinants of OW. A 46-year-old female with a history of low back pain after traumatic low back injury status post-IDDS placement for failed back surgery syndrome presented with signs and symptoms concerning for OW. After every other possible explanation was ruled out, it was hypothesized that there may be IDDS catheter microfracture(s), and catheter replacement led to symptom resolution. There were no significant differences in cytokine levels tested in pre-CSF versus post-CSF samples. Whole-cell patch-clamp electrophysiology analysis of human-induced pluripotent stem cell-derived nociceptors after treatment with pre- and post-CSF samples demonstrated modulation of action potential waveform. In patients presenting with acute OW attribution IDDS malfunction, catheter microfracture must be in the differential, and non-conventional interrogation of the IDDS catheter should be considered. The possible differences in pre-CSF and post-CSF may be more complicated than previously postulated, as there were no significant differences in cytokine profiles; however, treatment of in vitro neurons with pre- and post-CSF resulted in differential neuronal excitability, which may account for some of the symptoms of OW.

8.
Oper Neurosurg (Hagerstown) ; 19(3): E299, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31980830

RESUMO

There are approximately 12 000 new individuals with spinal cord injury (SCI) each year, and close to 200 000 individuals live with a SCI-related disability in the United States. The majority of patients with SCI have bladder dysfunction as a result of their injury, with over 75% unable to void volitionally following their injury. In patients with traumatic SCI, intermittent catheterization is commonly recommended, but a lack of adherence to clean intermittent catheterization (CIC) has been observed, with up to 50% discontinuing CIC within 5 yr of injury. The Finetech Brindley Bladder System (FBBS) is an implantable sacral nerve stimulator for improving bladder function in patients with SCI, avoiding the need for CIC. The FDA-approved implantation (Humanitarian Device Exemption H980008) of the FBBS is combined with a posterior rhizotomy to reduce reflex contraction of the bladder, improving continence. However, the posterior rhizotomy is irreversible and has unwanted effects; therefore, the current FDA-approved implantation is being studied without rhizotomy as part of a clinical trial (Investigational Device Exemption G150201) (ClinicalTrials.gov Identifier: NCT02978638). In this video, we present a case of a 66-yr-old female who presented 40-yr status post-T12 SCI, resulting in complete paraplegia and neurogenic bladder not satisfactorily controlled with CIC. We demonstrate the operative steps to complete the implantation of the device without rhizotomy in the first patient enrolled as part of the clinical trial Electrical Stimulation for Continence After SCI (NCT02978638). Appropriate IRB and patient consent were obtained.


Assuntos
Terapia por Estimulação Elétrica , Rizotomia , Traumatismos da Medula Espinal , Bexiga Urinaria Neurogênica , Feminino , Humanos , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/cirurgia , Bexiga Urinaria Neurogênica/etiologia , Bexiga Urinaria Neurogênica/terapia
9.
Spinal Cord ; 58(3): 377-386, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31649323

RESUMO

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To assess the impact of mean arterial blood pressure (MAP) during surgical intervention for spinal cord injury (SCI) on motor recovery. SETTING: Level-one Trauma Hospital and Acute Rehabilitation Hospital in San Jose, CA, USA. METHODS: Twenty-five individuals with traumatic SCI who received surgical and acute rehabilitation care at a level-one trauma center were included in this study. The Surgical Information System captured intraoperative MAPs on a minute-by-minute basis and exposure was quantified at sequential thresholds from 50 to 104 mmHg. Change in International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) motor score was calculated based on physiatry evaluations at the earliest postoperative time and at discharge from acute rehabilitation. Linear regression models were used to estimate the rate of recovery across the entire MAP range. RESULTS: An exploratory analysis revealed that increased time within an intraoperative MAP range (70-94 mmHg) was associated with ISNCSCI motor score improvement. A significant regression equation was found for the MAP range 70-94 mmHg (F[1, 23] = 5.07, r2 = 0.181, p = 0.034). ISNCSCI motor scores increased 0.039 for each minute of exposure to the MAP range 70-94 mmHg during the operative procedure; this represents a significant correlation between intraoperative time with MAP 70-94 and subsequent motor recovery. Blood pressure exposures above or below this range did not display a positive association with motor recovery. CONCLUSIONS: Hypertension as well as hypotension during surgery may impact the trajectory of recovery in individuals with SCI, and there may be a direct relationship between intraoperative MAP and motor recovery.


Assuntos
Pressão Arterial , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/reabilitação , Traumatismos da Medula Espinal/cirurgia , Adulto , Pressão Arterial/fisiologia , Determinação da Pressão Arterial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória , Recuperação de Função Fisiológica/fisiologia , Estudos Retrospectivos , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Tempo
10.
Pain Med ; 21(9): 1759-1768, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31578562

RESUMO

OBJECTIVE: Examine the interrelationship between smoking and pain in the US population. DESIGN: A cross-sectional population-based study. SETTING: Nationwide survey. METHODS: Comprehensive pain reports categorically defined as head, spine, trunk, and limb pain; smoking history; demographics; medical history from a total of 2,307 subjects from the 2003-2004 National Health and Nutrition Examination Survey obtained from the Centers for Disease Control were analyzed. Unpaired t tests were used to analyze independent continuous variables, and chi-square tests were used to analyze categorical variables between smoker and nonsmoker groups. Weighted multivariate logistic regression analyses determined the association of current smoking with the presence of pain in various body regions. RESULTS: Smoking is most strongly associated with spine pain (odds ratio [OR] = 2.89, 95% confidence interval [CI] = 2.21-3.77), followed by headache (OR = 2.47, 95% CI = 1.73-3.53), trunk pain (OR = 2.17, 95% CI = 1.45-2.74), and limb pain (OR = 1.99, 95% CI = 1.45-2.73). CONCLUSIONS: Current smoking is associated with pain in every region of the body. This association is strongest for spine and head pain. Given that pain is a strong motivator and that current smoking was associated with pain in all body regions, we recommend that these results be used to further raise public awareness about the potential harms of smoking.


Assuntos
Vértebras Lombares , Fumar , Estudos Transversais , Humanos , Inquéritos Nutricionais , Dor , Fumar/efeitos adversos
11.
Cancer Res ; 71(10): 3688-700, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21576089

RESUMO

Head and neck squamous cell carcinoma (HNSCC) and many other epithelial malignancies exhibit increased proliferation, invasion, and inflammation, concomitant with aberrant nuclear activation of TP53 and NF-κB family members ΔNp63, cRel, and RelA. However, the mechanisms of cross-talk by which these transcription factors coordinate gene expression and the malignant phenotype remain elusive. In this study, we showed that ΔNp63 regulates a cohort of genes involved in cell growth, survival, adhesion, and inflammation, which substantially overlaps with the NF-κB transcriptome. ΔNp63 with cRel and/or RelA are recruited to form novel binding complexes on p63 or NF-κB/Rel sites of multitarget gene promoters. Overexpressed ΔNp63- or TNF-α-induced NF-κB and inflammatory cytokine interleukin-8 (IL-8) reporter activation depended on RelA/cRel regulatory binding sites. Depletion of RelA or ΔNp63 by small interfering RNA (siRNA) significantly inhibited NF-κB-specific, or TNF-α-induced IL-8 reporter activation. ΔNp63 siRNA significantly inhibited proliferation, survival, and migration by HNSCC cells in vitro. Consistent with these data, an increase in nuclear ΔNp63, accompanied by increased proliferation (Ki-67) and adhesion (ß4 integrin) markers, and induced inflammatory cell infiltration was observed throughout HNSCC specimens, when compared with the basilar pattern of protein expression and minimal inflammation seen in nonmalignant mucosa. Furthermore, overexpression of ΔNp63α in squamous epithelial cells in transgenic mice leads to increased suprabasilar cRel, Ki-67, and cytokine expression, together with epidermal hyperplasia and diffuse inflammation, similar to HNSCC. Our study reveals ΔNp63 as a master transcription factor that, in coordination with NF-κB/Rels, orchestrates a broad gene program promoting epidermal hyperplasia, inflammation, and the malignant phenotype of HNSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/metabolismo , NF-kappa B/biossíntese , NF-kappa B/genética , Fosfoproteínas/fisiologia , Transativadores/fisiologia , Fatores de Transcrição/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Animais , Carcinoma de Células Escamosas/genética , Movimento Celular , Proliferação de Células , Células Epiteliais/citologia , Neoplasias de Cabeça e Pescoço/genética , Humanos , Inflamação , Interleucina-8/metabolismo , Antígeno Ki-67/biossíntese , Camundongos , Camundongos Transgênicos , Fenótipo , Fator de Transcrição RelA/metabolismo
12.
Cell Commun Signal ; 9: 13, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21569639

RESUMO

This is an in-depth review of the history of quinacrine as well as its pharmacokinetic properties and established record of safety as an FDA-approved drug. The potential uses of quinacrine as an anti-cancer agent are discussed with particular attention to its actions on nuclear proteins, the arachidonic acid pathway, and multi-drug resistance, as well as its actions on signaling proteins in the cytoplasm. In particular, quinacrine's role on the NF-κB, p53, and AKT pathways are summarized.

13.
Clin Cancer Res ; 16(8): 2295-307, 2010 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-20371694

RESUMO

PURPOSE: The aim of this study is to investigate the expression of CK2 subunits and CK2 effects on NF-kappaB-mediated and TP53-mediated signal activation and gene expression, the malignant phenotype, and chemosensitivity in head and neck squamous cell carcinoma (HNSCC) in vitro and in vivo. EXPERIMENTAL DESIGN: Protein expression of CK2 subunits was investigated by Western blot and immunohistochemistry. CK2 subunits were knocked down by small interfering RNA, and NF-kappaB activation was examined using DNA binding, Western blot, and luciferase reporter assays. Gene expression was measured by quantitative reverse transcription-PCR. Cell growth, survival, motility, and sensitivity to cisplatin were measured by MTT, flow cytometry, and migration assays. In vivo targeting of CK2alpha/alpha' in HNSCC xenograft models was achieved using anti-CK2alpha/alpha' oligodeoxynucleotide encapsulated in sub-50-nm tenfibgen nanocapsules. RESULTS: CK2 subunit proteins were overexpressed in HNSCC lines and tissues. Knockdown of CK2 subunits differentially inhibited IkappaBalpha degradation, NF-kappaB nuclear localization, phosphorylation, DNA binding, and reporter activity. CK2 subunits modulated gene expression and the malignant phenotype involved in cell cycle and migration, whereas CK2alpha is critical to promote proliferation, antiapoptosis, and cisplatin resistance in vitro. Furthermore, in vivo delivery of anti-CK2alpha/alpha' oligodeoxynucleotide nanocapsules significantly suppressed tumor growth in HNSCC xenograft models, in association with modulation of CK2 and NF-kappaB regulated molecules, TP53 family proteins, and induction of apoptosis. CONCLUSIONS: Our study reveals a novel role of CK2 in coregulating NF-kappaB activation, TP53/p63 expression, and downstream gene expression. Downregulation of CK2 in HNSCC models in vitro and in vivo shows antitumor effects as well as sensitization to cisplatin.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Caseína Quinase II/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , NF-kappa B/metabolismo , Oligonucleotídeos Antissenso/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Western Blotting , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Caseína Quinase II/antagonistas & inibidores , Caseína Quinase II/genética , Ciclo Celular , Movimento Celular , Proliferação de Células , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Luciferases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , NF-kappa B/genética , Nanocápsulas , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Cicatrização
14.
Clin Cancer Res ; 15(19): 5974-84, 2009 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-19789307

RESUMO

PURPOSE: Aberrant nuclear activation and phosphorylation of the canonical NF-kappaB subunit RELA/p65 at Serine-536 by inhibitor kappaB kinase is prevalent in head and neck squamous cell carcinoma (HNSCC), but the role of other kinases in NF-kappaB activation has not been well defined. Here, we investigated the prevalence and function of p65-Ser276 phosphorylation by protein kinase A (PKA) in the malignant phenotype and gene transactivation, and studied p65-Ser276 as a potential target for therapy. EXPERIMENTAL DESIGN: Phospho and total p65 protein expression and localization were determined in HNSCC tissue array and in cell lines. The effects of the PKA inhibitor H-89 on NF-kappaB activation, downstream gene expression, cell proliferation and cell cycle were examined. Knockdown of PKA by specific siRNA confirmed the specificity. RESULTS: NF-kappaB p65 phosphorylated at Ser276 was prevalent in HNSCC and adjacent dysplastic mucosa, but localized to the cytoplasm in normal mucosa. In HNSCC lines, tumor necrosis factor-alpha (TNF-alpha) significantly increased, whereas H-89 inhibited constitutive and TNF-alpha-induced nuclear p65 (Ser276) phosphorylation, and significantly suppressed NF-kappaB and target gene IL-8 reporter activity. Knockdown of PKA by small interfering RNA inhibited NF-kappaB, IL-8, and BCL-XL reporter gene activities. H-89 suppressed cell proliferation, induced cell death, and blocked the cell cycle in G(1)-S phase. Consistent with its biological effects, H-89 down-modulated expression of NF-kappaB-related genes Cyclin D1, BCL2, BCL-XL, COX2, IL-8, and VEGF, as well as induced cell cycle inhibitor p21(CIP1/WAF1), while suppressing proliferative marker Ki67. CONCLUSIONS: NF-kappaB p65 (Ser276) phosphorylation by PKA promotes the malignant phenotype and holds potential as a therapeutic target in HNSCC.


Assuntos
Carcinoma de Células Escamosas/etiologia , Núcleo Celular/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Neoplasias de Cabeça e Pescoço/etiologia , Fator de Transcrição RelA/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Ciclo Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Proliferação de Células/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Isoquinolinas/farmacologia , Mucosa/metabolismo , Mucosa/patologia , Fenótipo , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Transporte Proteico/efeitos dos fármacos , Transporte Proteico/fisiologia , RNA Interferente Pequeno/farmacologia , Serina/metabolismo , Sulfonamidas/farmacologia , Fator de Transcrição RelA/fisiologia , Células Tumorais Cultivadas
15.
Cancer Res ; 69(8): 3415-24, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19351843

RESUMO

Although constitutively activated nuclear factor-kappaB (NF-kappaB), attenuated transforming growth factor beta (TGFbeta) signaling, and TP53 mutations frequently occur in human cancers, how these pathways interact and together contribute to malignancy remains uncertain. Here, we found an association between overexpression of NF-kappaB-related genes, reduced expression of TGFbeta receptor (TbetaR) subunits and downstream targets, and TP53 genotype in head and neck squamous cell carcinoma (HNSCC). In response to recombinant TGFbeta1, both growth inhibition and TGFbeta target gene modulation were attenuated or absent in a panel of human HNSCC lines. However, in HNSCC cells that retained residual TGFbeta signaling, TGFbeta1 inhibited both constitutive and tumor necrosis factor alpha-stimulated NF-kappaB activity. Furthermore, HNSCC lines overexpressing mutant (mt) TP53 and human tumor specimens with positive TP53 nuclear staining exhibited reduced TbetaRII and knocking down mtTP53 induced TbetaRII, increasing TGFbeta downstream gene expression while inhibiting proinflammatory NF-kappaB target gene expression. Transfection of ectopic TbetaRII directly restored TGFbeta signaling while inhibiting inhibitor kappaBalpha degradation and suppressing serine-536 phosphorylation of NF-kappaB p65 and NF-kappaB transcriptional activation, linking these alterations. Finally, experiments with TbetaRII conditional knockout mice show that abrogation of TGFbeta signaling promotes the sustained induction of NF-kappaB and its proinflammatory target genes during HNSCC tumorigenesis and progression. Together, these findings elucidate a regulatory framework in which attenuated TGFbeta signaling promotes NF-kappaB activation and squamous epithelial malignancy in the setting of altered TP53 status.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , NF-kappa B/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Animais , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Deleção de Genes , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Humanos , Camundongos , NF-kappa B/antagonistas & inibidores , NF-kappa B/biossíntese , NF-kappa B/genética , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteoglicanas/biossíntese , Proteoglicanas/genética , Proteoglicanas/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/biossíntese , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Transcrição Gênica , Fator de Crescimento Transformador beta/biossíntese , Fator de Crescimento Transformador beta/deficiência , Fator de Crescimento Transformador beta/genética , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
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