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OBJECTIVE: To determine the rate of avoidable admissions following anticipated same-day discharge for patients undergoing minimally invasive hysterectomy and to identify risk factors associated with such admissions. METHODS: A retrospective review was performed of patients who underwent a minimally invasive hysterectomy between March 2019 and July 2021 for a suspected gynecologic malignancy at a single tertiary care center. Pre-operatively, patients were assessed for same-day discharge versus planned admission. Reasons for day-of-surgery admission despite anticipated same-day discharge were categorized as anesthesia-related, system issues, intra-operative factors, post-operative pain, and social factors. Patients deemed not candidates for same-day discharge were defined as planned admissions. Indications were categorized as necessary or potentially avoidable. Descriptive and comparative statistics were used to summarize the cohort. RESULTS: In total, 372 patients were identified: 261 (70.2%) anticipated same-day discharges and 111 (29.8%) planned admissions. Of anticipated same-day discharges, 230/261 (88.1%) were successfully discharged, while 31/261 (11.9%) required admission. Reasons for unplanned admissions were anesthesia-related (14/31, 45.2%), system issues (7/31, 22.6%), intra-operative factors (5/31, 16.1%), post-operative pain (3/31, 9.7%), and social factors (2/31, 6.5%). Among the 111 pre-operatively planned admissions, 81 (73.0%) were necessary due to comorbidities or surgical complexity, while 30 (27.0%) were potentially avoidable because patients could have been optimized for same-day discharge. Opportunities for optimization pre-operatively included comorbidities (13/30, 43.3%), system issues (8/30, 26.7%), social factors (6/30, 20.0%), and provider preference (3/30, 10.0%). CONCLUSION: Most patients undergoing minimally invasive hysterectomy can be safely discharged the same day. Potentially avoidable admissions were primarily related to patient comorbidities that can be better optimized pre-operatively.
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BACKGROUND: The potential for the technique of small bite fascial closure in mitigating incisional hernias in gynecologic oncology patients still needs to be investigated. OBJECTIVE: To evaluate the impact of closure of small fascial bites compared with prior standard closure on incisional hernia rates in gynecologic oncology patients. METHODS: This is a retrospective cohort study comparing patient outcomes before and after the intervention at a single institution at a comprehensive cancer center. Patients who underwent laparotomy with a vertical midline incision for a suspected or known gynecologic malignancy with a 1-year follow-up were included. The pre-intervention cohort (large bites) had 'mass' or modified running Smead-Jones closure. In contrast, the post-intervention cohort had fascial bites taken 5-8 mm laterally with no more than 5 mm travel (small bites) closure using a 2-0 polydioxanone suture.The primary outcome was the incisional hernias rate determined by imaging or clinical examination within the first year of follow-up. Patient factors and peri-operative variates of interest were investigated for their association with hernia formation through univariate and multivariate analyses. These included age, body mass index (BMI), smoking history, estimated blood loss, pre-operative albumin, American Society of Anesthesia (ASA) physical status classification, or treatment with chemotherapy post-operatively. RESULTS: Of the 255 patients included, the total hernia rate was 12.5% (32/255 patients). Patient characteristics were similar in both cohorts. Small bite closure led to a significant reduction in hernia rates from 17.2% (22/128 patients) to 7.9% (10/127 patients), p=0.025. According to logistic regression modeling, small bite closure (OR=0.40, 95% CI 0.17 to 0.94, p=0.036) was independently associated with lower odds of hernia formation. Other factors associated with increased hernia rates were chemotherapy (OR=3.22, 95% CI 1.22 to 8.51, p=0.019) and obesity (OR=23.4, 95% CI 3.09 to 177, p=0.002). In obese patients, small bite closures led to maximal hernia rate reduction compared with large bites. CONCLUSIONS: The small bite closure technique effectively reduces hernia rates in gynecologic oncology patients undergoing midline laparotomy.
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Neoplasias dos Genitais Femininos , Hérnia Incisional , Humanos , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Hérnia Incisional/prevenção & controle , Hérnia Incisional/epidemiologia , Neoplasias dos Genitais Femininos/cirurgia , Idoso , Adulto , Fasciotomia/métodos , Estudos de CoortesRESUMO
OBJECTIVE: To compare the venous thromboembolism (VTE) rate in patients with ovarian cancer undergoing neoadjuvant chemotherapy before and after implementing routine thromboprophylaxis. METHODS: This is a quasi-experimental pre-post study evaluating the VTE rate in patients with ovarian cancer who received neoadjuvant chemotherapy following a quality improvement initiative of routine thromboprophylaxis within a single healthcare system that started in January 2017. Patients were excluded if VTE was diagnosed before initiating chemotherapy. Patient factors and perioperative variables of interest were investigated for their association with VTE through univariate and multivariate models. RESULTS: Of the 136 patients in the pre-implementation group, 3.7% (n = 5) received thromboprophylaxis. Of the 154 patients in the post-implementation group, 65.6% (n = 101) received thromboprophylaxis. Provider compliance varied from 51% in 2019 to 79.3% in 2021. The overall rate of VTE, from the start of chemotherapy to the end of treatment, was 21.3% (n = 29) pre- and 8.4% (n = 13) in the post-implementation group (p < 0.01). There was no difference in major bleeding events between groups (0% vs. 0.68%, p = 0.63). On univariate analysis, thromboprophylaxis (OR 0.19; 95% CI 0.07-0.52) and post-implementation period (OR 0.34; 95% CI 0.17-0.69) were associated with a decreased risk of any VTE during primary treatment. On multivariate analysis, only thromboprophylaxis remained significantly associated with reduced VTE rates (aOR 0.19; 95% CI 0.07-0.53). CONCLUSION: Routine thromboprophylaxis during neoadjuvant chemotherapy is associated with reduced risk of VTE throughout primary treatment and is not associated with increased bleeding events.
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Neoplasias Ovarianas , Tromboembolia Venosa , Humanos , Feminino , Anticoagulantes , Tromboembolia Venosa/epidemiologia , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/prevenção & controle , Terapia Neoadjuvante , Hemorragia/induzido quimicamente , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/induzido quimicamenteRESUMO
OBJECTIVE: To evaluate the impact a tailored opioid prescription calculator has on meeting individual patient opioid needs while avoiding opioid over prescriptions. METHODS: Our group previously developed and published an opioid prescribing calculator incorporating patient risk factors (history of depression, anxiety, chronic opioid use, substance abuse disorder, and/or chronic pain) and type of surgery (laparotomy or laparoscopy). This calculator was implemented on 1/1/2021 and its impact on opioid prescriptions was evaluated until 12/31/21. The primary outcome of the present study is to determine prescriber compliance with the calculator (defined as not overprescribing from the number of pills indicated by the calculator). The secondary outcome is to determine the excess prescription rate (defined as proportion of patients reporting more than 3 pills remaining at 30 days post-surgery). Refill rates and pain related patient phone calls were collected. Descriptive statistics were used to summarize the cohort. RESULTS: Of the 355 patients included, 54.7% (N = 194) underwent laparoscopy and 45.4% (N = 161) underwent laparotomy. One hundred and forty-two patients (40%) had at least one risk factor for opioid usage. The median number of opioid pills prescribed following laparoscopy was 3 (range 0-15) and 6 (0-20) after laparotomy. The prescriber compliance was 88.2% and the excess prescription rate was 25.1% (N = 89 patients). CONCLUSIONS: Our tailored opioid calculator has a high prescriber compliance. Implementation of this calculator led to a standardization of tailored opioid prescribing, while limiting the number of over prescriptions. A free web version of the calculator can be easily accessed at www.opioidcalculator.org.
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Analgésicos Opioides , Dor Pós-Operatória , Humanos , Feminino , Analgésicos Opioides/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica , Procedimentos Cirúrgicos em Ginecologia/efeitos adversos , Prescrições de MedicamentosRESUMO
OBJECTIVE: To implement a quality-improvement initiative to assess the impact various patient and procedural factors have on postoperative opioid use. To develop a tailored opioid prescribing algorithm for gynecologic oncology patients. METHODS: A retrospective cohort study was performed of patients who underwent a laparoscopy or laparotomy procedure for a suspected or known gynecologic malignancy between 3/2019-9/2020. Patients were assessed preoperatively for the presence of suspected risk factors for opioid misuse (depression, anxiety, chronic pain, current opioid use, or substance abuse). Patients completed a 30-day postoperative questionnaire assessing for total opioid pill use and refills requests. Multivariate models were developed to estimate the independent effect of sociodemographic characteristics, risk factors for opioid misuse and procedural factors on patient reported postoperative opioid use. RESULTS: A total of 390 patients were analyzed. Thirty-nine percent (N = 151/390) of patients reported not using opioids after discharge and 5% (N = 20/390) received an opioid refill. For both minimally invasive procedures and laparotomy procedures, body mass index, comorbidities, intraoperative or postoperative complications and final diagnosis of malignancy were not associated with the amount of opioid consumption. However, younger age and history of risk factors for opioid misuse significantly impacted postoperative opioid use. In multivariate analysis, age (p = 0.038) and risk factors (p < 0.001) remained significant after controlling for other factors. CONCLUSIONS: Two out of every five patients did not use opioids after surgery. Younger patients and those with risk factors for opioid misuse need a tailored approach to prescribing opioids to balance the need for adequate pain control with the risk of misuse.
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Analgésicos Opioides/uso terapêutico , Neoplasias dos Genitais Femininos/cirurgia , Dor Pós-Operatória/tratamento farmacológico , Adulto , Feminino , Humanos , Michigan , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Padrões de Prática Médica/normas , Melhoria de Qualidade , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/prevenção & controleRESUMO
Robust preclinical models of ovarian high-grade serous carcinoma (HGSC) are needed to advance our understanding of HGSC pathogenesis and to test novel strategies aimed at improving clinical outcomes for women with the disease. Genetically engineered mouse models of HGSC recapitulating the likely cell of origin (fallopian tube), underlying genetic defects, histology, and biologic behavior of human HGSCs have been developed. However, the degree to which the mouse tumors acquire the somatic genomic changes, gene expression profiles, and immune microenvironment that characterize human HGSCs remains unclear. We used integrated molecular characterization of oviductal HGSCs arising in the context of Brca1, Trp53, Rb1, and Nf1 (BPRN) inactivation to determine whether the mouse tumors recapitulate human HGSCs across multiple domains of molecular features. Targeted DNA sequencing showed the mouse BPRN tumors, but not endometrioid carcinoma-like tumors based on different genetic defects (e.g., Apc and Pten), acquire somatic mutations and widespread copy number alterations similar to those observed in human HGSCs. RNA sequencing showed the mouse HGSCs most closely resemble the so-called immunoreactive and mesenchymal subsets of human HGSCs. A combined immuno-genomic analysis demonstrated the immune microenvironment of BPRN tumors models key aspects of tumor-immune dynamics in the immunoreactive and mesenchymal subtypes of human HGSC, with enrichment of immunosuppressive cell subsets such as myeloid-derived suppressor cells and regulatory T cells. The findings further validate the BPRN model as a robust preclinical experimental platform to address current barriers to improved prevention, diagnosis, and treatment of this often lethal cancer. SIGNIFICANCE: The acquired gene mutations, broad genomic alterations, and gene expression and immune cell-tumor axis changes in a mouse model of oviductal serous carcinoma closely mirror those of human tubo-ovarian high-grade serous carcinoma.
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Cistadenocarcinoma Seroso/genética , Neoplasias das Tubas Uterinas/genética , Neurofibromina 1/genética , Neoplasias Ovarianas/genética , Microambiente Tumoral/imunologia , Animais , Carcinoma Endometrioide/genética , Carcinoma Endometrioide/imunologia , Carcinoma Endometrioide/patologia , Cistadenocarcinoma Seroso/imunologia , Cistadenocarcinoma Seroso/patologia , Modelos Animais de Doenças , Neoplasias das Tubas Uterinas/imunologia , Neoplasias das Tubas Uterinas/patologia , Tubas Uterinas/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Células Supressoras Mieloides/imunologia , Neoplasias Ovarianas/imunologia , RNA-Seq , Linfócitos T Reguladores/imunologiaRESUMO
Most high-grade serous carcinomas are thought to arise from Fallopian tube epithelium (FTE), but some likely arise outside of the tube, perhaps from ectopic tubal-type epithelium known as endosalpingiosis. Importantly, the origin of endosalpingiosis is poorly understood. The proximity of the tubal fimbriae to the ovaries has led to the proposal that disruptions in the ovarian surface that occur during ovulation may allow detached FTE to implant in the ovary and form tubal-type glands and cysts. An alternative model suggests that cells present in ectopic locations outside the Müllerian tract retain the capacity for multi-lineage differentiation and can form glands with tubal-type epithelium. We used double transgenic Ovgp1-iCreERT2 ;R26RLSL-eYFP mice, which express an eYFP reporter protein in OVGP1-positive tissues following transient tamoxifen (TAM) treatment, to track the fate of oviductal epithelial cells. Cohorts of adult mice were given TAM to activate eYFP expression in oviductal epithelium, and ovaries were examined at time points ranging from 2 days to 12 months post-TAM. To test whether superovulation might increase acquisition of endosalpingiosis, additional cohorts of TAM-treated mice underwent up to five cycles of superovulation and ovaries were examined at 1, 6, and 12 months post-TAM. Ovaries were sectioned in their entirety to identify endosalpingiosis. Immunohistochemical staining for PAX8, tubulin, OVGP1, and eYFP was employed to study endosalpingiosis lesions. Ovarian endosalpingiosis was identified in 14.2% of TAM-treated adult mice. The endosalpingiotic inclusion glands and cysts were lined by secretory and ciliated cells and expressed PAX8, tubulin, OVGP1, and eYFP. Neither age nor superovulation was associated with a significant increase in endosalpingiosis. Endosalpingiosis was also occasionally present in the ovaries of pre-pubertal mice. The findings imply that ovarian endosalpingiosis in the mouse does not likely arise as a consequence of detachment and implantation of tubal epithelium and other mechanisms may be relevant. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
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Linhagem da Célula , Células Epiteliais/patologia , Neoplasias das Tubas Uterinas/patologia , Tubas Uterinas/patologia , Neoplasias Císticas, Mucinosas e Serosas/patologia , Neoplasias Ovarianas/patologia , Ovário/patologia , Animais , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Rastreamento de Células/métodos , Células Epiteliais/metabolismo , Neoplasias das Tubas Uterinas/genética , Neoplasias das Tubas Uterinas/metabolismo , Tubas Uterinas/metabolismo , Feminino , Glicoproteínas/genética , Integrases/genética , Proteínas Luminescentes/biossíntese , Proteínas Luminescentes/genética , Camundongos Transgênicos , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Císticas, Mucinosas e Serosas/metabolismo , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Fator de Transcrição PAX8/metabolismo , RNA não Traduzido/genética , Superovulação , Tubulina (Proteína)/metabolismoRESUMO
BACKGROUND: The oncologic safety of allogeneic blood transfusion in ovarian cancer patients is unknow. We sought to determine the prevalence and oncologic safety of perioperative allogeneic blood transfusion during interval cytoreduction surgery among women receiving neoadjuvant chemotherapy for ovarian cancer. METHODS: We utilized retrospective chart review to identify a cohort of patients undergoing interval cytoreduction at a large academic tertiary referral center. We compared outcomes in patients who were exposed to perioperative blood transfusion compared with patients who were not exposed. Our primary endpoint was progression free survival; our secondary endpoint was overall survival. Baseline clinical characteristics were collected for patients in each group. RESULTS: Sixty-six women were included in the final cohort of women undergoing interval cytoreductive surgery after NACT. A total of 51 women (77%) were exposed to allogeneic perioperative pRBC transfusion. Fifteen women (23%) were not exposed to transfusion. The baseline characteristics were generally well matched. Women who were not exposed to a perioperative blood transfusion were more likely to have a normalized CA125 prior to undergoing cytoreductive surgery. Preoperative hemoglobin concentration was lower in the transfusion group (10.5 g/dLvs 11.5 g/dL, p < 0.009). Perioperative transfusion was not associated with a significant difference in progression free survival (PFS = 7.6 months for transfused, 9.4 months for not transfused; log-rank test p = 0.4617). Similarly, there was no observed difference between groups for overall survival (OS = 23.6 months for transfused, 22.5 months for not transfused; log-rank test p = 0.1723). CONCLUSIONS: Women undergoing neoadjuvant chemotherapy for ovarian cancer are at high risk of exposure to blood transfusion at the time of interval cytoreductive surgery. Future studies will continue to evaluate the safety and impact of transfusion on ovarian cancer survival in this at risk population.
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Perda Sanguínea Cirúrgica , Transfusão de Sangue/estatística & dados numéricos , Quimioterapia Adjuvante/efeitos adversos , Procedimentos Cirúrgicos de Citorredução , Terapia Neoadjuvante/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Procedimentos Cirúrgicos de Citorredução/efeitos adversos , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Período Perioperatório , Estudos RetrospectivosRESUMO
BACKGROUND: Transfusion related immune modulation associated with red blood cell (RBC) transfusion is thought to result in decreased cancer survival. Results in epithelial ovarian cancer (EOC) have been mixed however most suggest worse oncologic outcomes in patients who were transfused at the time of debulking surgery. The impact of restrictive transfusion strategies on this patient population is currently not known. METHODS: We conducted a retrospective study of women with EOC. The study population was divided into two groups based on whether they were transfused RBCs during the peri-operative period or not. Clinical characteristics and prognosticators were compared between groups. Overall survival was compared between groups based on transfusion status and other known prognostic factors. Cox proportional hazard modeling was used to examine the association between the prognostic factors and the study endpoint. RESULTS: Sixty-six percent of women were transfused. Transfusion was associated with CA125, the use of neoadjuvant chemotherapy (NACT), surgical blood loss, and anemia. The mean pre-transfusion Hgb was 7.8â¯+â¯0.6â¯g/dL and 94% had a hemoglobin level greater than the transfusion threshold of 7â¯g/dL. RBC transfusion, suboptimal debulking, anemia, and NACT were associated with decreased survival. Only RBC transfusion and suboptimal debulking status remained significant in a multivariate model. CONCLUSIONS: Peri-operative RBC transfusion compromises survival in ovarian cancer supporting the need to minimize the use of transfusion at the time of debulking surgery. Adherence to evidence-based transfusion guidelines offers an opportunity to reduce transfusion rates in this population with a resulting positive influence on survival.
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Transfusão de Eritrócitos/métodos , Neoplasias Epiteliais e Glandulares/terapia , Neoplasias Ovarianas/terapia , Idoso , Antígeno Ca-125/sangue , Carcinoma Epitelial do Ovário , Quimioterapia Adjuvante , Procedimentos Cirúrgicos de Citorredução/métodos , Feminino , Humanos , Proteínas de Membrana/sangue , Terapia Neoadjuvante , Estadiamento de Neoplasias , Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/cirurgia , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/cirurgia , Assistência Perioperatória/métodos , Estudos RetrospectivosRESUMO
OBJECTIVE: The purpose of this case-controlled study was to determine the prevalence of anemia and incidence of perioperative blood transfusions in patients undergoing treatment for advanced ovarian cancer with neoadjuvant chemotherapy (NACT) or primary debulking surgery (PDS). METHODS: We performed a single institution review of patients diagnosed with stage IIIB-IVB epithelial ovarian cancer between 2010 and 2013 undergoing either NACT or PDS. Anemia was defined as a hemoglobin (Hgb) concentration of ≤11.5â¯g/dL. Continuous variables were compared by student t-test and binary variables compared via chi square analysis. RESULTS: One hundred thirty-one women were included, 66 treated with NACT and 65 treated with PDS. Average Hgb prior to surgery was lower in women who received NACT (10.7â¯g/dL vs 12.8â¯g/dL, pâ¯<â¯0.0001). Women treated with NACT had a decrease in mean Hgb during chemotherapy treatment (11.8â¯g/dL at diagnosis to 10.7â¯g/dL preoperatively). Seventy-seven percent of NACT patients were anemic prior to surgery compared to 15% of patients prior to PDS (pâ¯<â¯0.001). Mean EBL at debulking was higher in patients selected for PDS (871â¯mL) than NACT (544â¯mL); however, the perioperative transfusion rate was higher during interval debulking surgeries (NACT 77% vs PDS 56%, pâ¯=â¯0.01). CONCLUSION: Women selected for NACT were more likely to be anemic at diagnosis and became progressively anemic during NACT. Despite less blood loss during debulking surgery, NACT patients receive more blood transfusions perioperatively than patients undergoing PDS. This represents a potential opportunity for therapeutic intervention during NACT to correct anemia prior to interval debulking surgery.
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Anemia/etiologia , Transfusão de Sangue/métodos , Quimioterapia Adjuvante/efeitos adversos , Procedimentos Cirúrgicos de Citorredução/métodos , Neoplasias Ovarianas/complicações , Idoso , Anemia/patologia , Estudos de Casos e Controles , Quimioterapia Adjuvante/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/cirurgia , Período Perioperatório , Estudos RetrospectivosRESUMO
Activation of IκB kinase (IKK) and NF-κB by genotoxic stresses modulates apoptotic responses and production of inflammatory mediators, thereby contributing to therapy resistance and premature aging. We previously reported that genotoxic agents induce nuclear localization of NF-κB essential modulator (NEMO) via an undefined mechanism to arbitrate subsequent DNA damage-dependent IKK/NF-κB signaling. Here we show that a nonclassical nuclear import pathway via IPO3 (importin 3, transportin 2) mediates stress-induced NEMO nuclear translocation. We found putative nuclear localization signals in NEMO whose mutations disrupted stress-inducible nuclear translocation of NEMO and IKK/NF-κB activation in stably reconstituted NEMO-deficient cells. RNAi screening of both importin α and ß family members, as well as co-immunoprecipitation analyses, revealed that a nonclassical importin ß family member, IPO3, was the only importin that was able to associate with NEMO and whose reduced expression prevented genotoxic stress-induced NEMO nuclear translocation, IKK/NF-κB activation, and inflammatory cytokine transcription. Recombinant IPO3 interacted with recombinant NEMO but not the nuclear localization signal mutant version and induced nuclear import of NEMO in digitonin-permeabilized cells. We also provide evidence that NEMO is disengaged from IKK complex following genotoxic stress induction. Thus, the IPO3 nuclear import pathway is an early and crucial determinant of the IKK/NF-κB signaling arm of the mammalian DNA damage response.
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Dano ao DNA , Quinase I-kappa B/metabolismo , NF-kappa B/imunologia , beta Carioferinas/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Animais , Linhagem Celular , Células HEK293 , Células HeLa , Humanos , Quinase I-kappa B/química , Quinase I-kappa B/imunologia , Camundongos , Dados de Sequência Molecular , Sinais de Localização Nuclear , beta Carioferinas/imunologiaRESUMO
NF-κB essential modulator, NEMO, plays a key role in canonical NF-κB signaling induced by a variety of stimuli, including cytokines and genotoxic agents. To dissect the different biochemical and functional roles of NEMO in NF-κB signaling, various mutant forms of NEMO have been previously analyzed. However, transient or stable overexpression of wild-type NEMO can significantly inhibit NF-κB activation, thereby confounding the analysis of NEMO mutant phenotypes. What levels of NEMO overexpression lead to such an artifact and what levels are tolerated with no significant impact on NEMO function in NF-κB activation are currently unknown. Here we purified full-length recombinant human NEMO protein and used it as a standard to quantify the average number of NEMO molecules per cell in a 1.3E2 NEMO-deficient murine pre-B cell clone stably reconstituted with full-length human NEMO (C5). We determined that the C5 cell clone has an average of 4 x 10(5) molecules of NEMO per cell. Stable reconstitution of 1.3E2 cells with different numbers of NEMO molecules per cell has demonstrated that a 10-fold range of NEMO expression (0.6-6x10(5) molecules per cell) yields statistically equivalent NF-κB activation in response to the DNA damaging agent etoposide. Using the C5 cell line, we also quantified the number of NEMO molecules per cell in several commonly employed human cell lines. These results establish baseline numbers of endogenous NEMO per cell and highlight surprisingly normal functionality of NEMO in the DNA damage pathway over a wide range of expression levels that can provide a guideline for future NEMO reconstitution studies.
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Dano ao DNA/fisiologia , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Células Precursoras de Linfócitos B/metabolismo , Animais , Linhagem Celular , Humanos , Camundongos , Transdução de Sinais/fisiologiaRESUMO
The NF-κB family of transcription factors regulates numerous cellular processes, including cell proliferation and survival responses. The constitutive activation of NF-κB has also emerged as an important oncogenic driver in many malignancies, such as activated B-cell like diffuse large B cell lymphoma, among others. In this study, we investigated the impact and mechanisms of action of Withaferin A, a naturally produced steroidal lactone, against both signal-inducible as well as constitutive NF-κB activities. We found that Withaferin A is a robust inhibitor of canonical and constitutive NF-κB activities, leading to apoptosis of certain lymphoma lines. In the canonical pathway induced by TNF, Withaferin A did not disrupt RIP1 polyubiquitination or NEMO-IKKß interaction and was a poor direct IKKß inhibitor, but prevented the formation of TNF-induced NEMO foci which colocalized with TNF ligand. While GFP-NEMO efficiently formed TNF-induced foci, a GFP-NEMO(Y308S) mutant that is defective in binding to polyubiquitin chains did not form foci. Our study reveals that Withaferin A is a novel type of IKK inhibitor which acts by disrupting NEMO reorganization into ubiquitin-based signaling structures in vivo.
Assuntos
Células-Tronco Embrionárias/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , NF-kappa B/metabolismo , Células Precursoras de Linfócitos B/efeitos dos fármacos , Ubiquitina/metabolismo , Vitanolídeos/farmacologia , Animais , Western Blotting , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Ensaio de Desvio de Mobilidade Eletroforética , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Citometria de Fluxo , Imunofluorescência , Humanos , Quinase I-kappa B/metabolismo , Técnicas Imunoenzimáticas , Imunoprecipitação , Peptídeos e Proteínas de Sinalização Intracelular/química , Camundongos , Camundongos Knockout , Células Precursoras de Linfócitos B/citologia , Células Precursoras de Linfócitos B/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , UbiquitinaçãoRESUMO
The dimeric transcription factor nuclear factor κB (NF-κB) functions broadly in coordinating cellular responses during inflammation and immune reactions, and its importance in the pathogenesis of cancer is increasingly recognized. Many of the signal transduction pathways that trigger activation of cytoplasmic NF-κB in response to a broad array of immune and inflammatory stimuli have been elaborated in great detail. NF-κB can also be activated by DNA damage, though relatively less is known about the signal transduction mechanisms that link DNA damage in the nucleus with activation of NF-κB in the cytoplasm. Here, we focus on the conserved signaling pathway that has emerged that promotes NF-κB activation following DNA damage. Post-translational modification of NF-κB essential modulator (NEMO) plays a central role in linking the cellular DNA damage response to NF-κB via the ataxia telangiectasia mutated (ATM) kinase. Accumulating evidence suggests that DNA damage-dependent NF-κB activation may play significant biological roles, particularly during lymphocyte differentiation and progression of human malignancies.
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Dano ao DNA , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ativação Enzimática/genética , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
In this issue of Molecular Cell, Stilmann et al. (2009) demonstrate a new mode of prosurvival NF-kappaB activation through the formation of a PARP-1-poly(ADP-ribose) signaling scaffold in response to DNA damage.
Assuntos
Dano ao DNA , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Transdução de Sinais , Animais , Proteínas Mutadas de Ataxia Telangiectasia , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/citologia , Fibroblastos/metabolismo , Fibroblastos/efeitos da radiação , Quinase I-kappa B/genética , Quinase I-kappa B/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Biológicos , NF-kappa B/metabolismo , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/genética , Poli(ADP-Ribose) Polimerases/metabolismo , Ligação Proteica , Proteínas Inibidoras de STAT Ativados/genética , Proteínas Inibidoras de STAT Ativados/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/metabolismoRESUMO
We have examined the role of histone acetylation in the very earliest steps of differentiation of mouse embryonic stem cells in response to withdrawal of leukemia inhibitory factor (LIF) as a differentiation signal. The cells undergo dramatic changes in morphology and an ordered program of gene expression changes representing differentiation to all three germ layers over the first 3-5 days of LIF withdrawal. We observed a global increase in acetylation on histone H4 and to a lesser extent on histone H3 over this time period. Treatment of the cells with trichostatin A (TSA), a histone deacetylase inhibitor, induced changes in morphology, gene expression, and histone acetylation that mimicked differentiation induced by withdrawal of LIF. We examined localized histone acetylation in the regulatory regions of genes that were transcriptionally either active in undifferentiated cells, induced during differentiation, or inactive under all treatments. There was striking concordance in the histone acetylation patterns of specific genes induced by both TSA and LIF withdrawal. Increased histone acetylation in local regions correlated best with induction of gene expression. Finally, TSA treatment did not support the maintenance or progression of differentiation. Upon removal of TSA, the cells reverted to the undifferentiated phenotype. We concluded that increased histone acetylation at specific genes played a role in their expression, but additional events are required for maintenance of differentiated gene expression and loss of the pluripotent state.
Assuntos
Diferenciação Celular , Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Histonas/metabolismo , Acetilação , Animais , Células Cultivadas , Células-Tronco Embrionárias/metabolismo , Ácidos Hidroxâmicos/farmacologia , Fator Inibidor de Leucemia/fisiologia , Camundongos , Células-Tronco PluripotentesRESUMO
Embryonic stem (ES) cells are pluripotent cells capable of unlimited self-renewal and differentiation into the three embryonic germ layers under appropriate conditions. Mechanisms for control of the early period of differentiation, involving exit from the pluripotent state and lineage commitment, are not well understood. An emerging concept is that epigenetic histone modifications may play a role during this early period. We have found that upon differentiation of mouse ES cells by removal of the cytokine leukemia inhibitory factor, there is a global increase in coupled histone H3 phosphorylation (Ser-10)-acetylation (Lys-14) (H3 phosphoacetylation). We show that this occurs through activation of both the extracellular signal-regulated kinase (ERK) and p38 MAPK signaling pathways. Early ES cell differentiation is delayed using pharmacological inhibitors of the ERK and p38 pathways. One common point of convergence of these pathways is the activation of the mitogen- and stress-activated protein kinase 1 (MSK1). We show here that MSK1 is the critical mediator of differentiation-induced H3 phosphoacetylation using both the chemical inhibitor H89 and RNA interference. Interestingly, inhibition of H3 phosphoacetylation also alters gene expression during early differentiation. These results point to an important role for both epigenetic histone modifications and kinase pathways in modulating early ES differentiation.