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1.
Br J Ophthalmol ; 2021 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-33836988

RESUMEN

PURPOSE: Presence of SARS-CoV-2 RNA in human retinal biopsies (RBs) was previously reported by us. In this consecutive study, we analysed RB and optic nerve biopsies (ONBs) in deceased patients with confirmed COVID-19 assessing viral RNA load, possible virus replication and infectivity. PATIENTS AND METHODS: In this case series, 14 eyes of 14 deceased patients with COVID-19 were enucleated during autopsy. RB and ONB were subjected to molecular detection of viral RNA, virus cultivation and immunohistochemistry. SARS-CoV-2 RNA loads were compared with RNA loads in the respective throat swabs, vitreous humour and blood samples. RESULTS: SARS-CoV-2 RNA was detected in 7/14 RBs and in 10/13 ONBs. While virus isolation failed and immunohistochemistry of SARS-CoV-2 spike protein was negative, subgenomic RNA (sgRNA) was detectable (40% RB; 60% ONB). CONCLUSION: SARS-CoV-2 RNA is detectable in RB and ONB of patients with COVID-19. Presence of sgRNA could point to a SARS-CoV-2 infection of neuronal tissue, but as virus isolation failed and immunohistochemistry of SARS-CoV-2 spike protein was negative, an active infection seems unlikely.

2.
J Clin Virol ; 137: 104782, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33711691

RESUMEN

BACKGROUND: SARS-CoV-2 molecular diagnostics is facing material shortages and long turnaround times due to exponential increase of testing demand. OBJECTIVE: We evaluated the analytic performance and handling of four rapid Antigen Point of Care Tests (AgPOCTs) I-IV (Distributors: (I) Roche, (II) Abbott, (III) MEDsan and (IV) Siemens). METHODS: 100 RT-PCR negative and 84 RT-PCR positive oropharyngeal swabs were prospectively collected and used to determine performance and accuracy of these AgPOCTs. Handling was evaluated by 10 healthcare workers/users through a questionnaire. RESULTS: The median duration from symptom onset to sampling was 6 days (IQR 2-12 days). The overall respective sensitivity were 49.4 % (CI95 %: 38.9-59.9), 44.6 % (CI95 %: 34.3-55.3), 45.8 % (CI95 %: 35.5-56.5) and 54.9 % (CI95 %: 43.4-65.9) for tests I, II, III and IV, respectively. In the high viral load subgroup (containing >106 copies of SARS-CoV-2 /swab, n = 26), AgPOCTs reached sensitivities of 92.3 % or more (range 92.3 %-100 %). Specificity was 100 % for tests I, II (CI95 %: 96.3-100 for both tests) and IV (CI95 %: 96.3-100) and 97 % (CI95 %: 91.5-98.9) for test III. Regarding handling, test I obtained the overall highest scores, while test II was considered to have the most convenient components. Of note, users considered all assays, with the exception of test I, to pose a significant risk for contamination by drips or spills. DISCUSSION: Besides some differences in sensitivity and handling, all four AgPOCTs showed acceptable performance in high viral load samples. However, due to the significantly lower sensitivity compared to RT-qPCR, a careful consideration of pro and cons of AgPOCT has to be taken into account before clinical implementation.

3.
JAMA Ophthalmol ; 2021 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-33475692

RESUMEN

Importance: Current recommendations are to avoid tissue for corneal transplant from donors with coronavirus disease 2019 (COVID-19) or those who were recently exposed to COVID-19 owing to the lack of knowledge about the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in corneal tissues. Evidence of SARS-CoV-2 in corneal tissue would seem to have clinical relevance for corneal transplant. Objectives: To investigate the presence of viral SARS-CoV-2 RNA in corneal discs of deceased patients with confirmed COVID-19 and assess viral genomic and subgenomic RNA load, possible infectivity, and histologic abnormalities. Design, Setting, and Participants: A case series was conducted of 11 deceased patients with COVID-19 who underwent autopsy between March 20 and May 14, 2020. Eleven corneal discs (1 corneal disc per patient) were harvested for molecular detection of viral genomic and subgenomic RNA, virus isolation, and immunohistochemistry. The SARS-CoV-2 RNA loads were compared with RNA loads in the conjunctival and throat swab samples and aqueous humor, vitreous humor, and blood samples. Main Outcomes and Measures: Evidence of SARS-CoV-2 RNA in human corneas. Results: This study comprised 11 patients (6 women [55%]; mean [SD] age, 68.5 [18.8] years). In 6 of 11 eyes (55%), SARS-CoV-2 genomic RNA was detected in the cornea; subgenomic RNA was present in 4 of these 6 eyes (67%). Infectivity or the presence of viral structural proteins could not be confirmed in any eye. However, patients whose corneal disc was positive for SARS-CoV-2 RNA also had positive results for SARS-CoV-2 RNA in 4 of 6 conjunctival swab samples, 1 of 3 aqueous humor samples, 3 of 5 vitreous humor samples, and 4 of 5 blood samples. Overall, conjunctival swab samples had positive results for SARS-CoV-2 RNA in 5 of 11 cases. Postmortem SARS-CoV-2 viremia was detected in 5 of 9 patients. Conclusions and Relevance: Viral genomic and subgenomic RNA of SARS-CoV-2 was detected in the cornea of patients with COVID-19 viremia. The risk of COVID-19 infection via corneal transplant is low even in donors with SARS-CoV-2 viremia, but further research is necessary to assess the rate of SARS-CoV-2 transmission via corneal transplant.

4.
J Med Microbiol ; 70(2)2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33404401

RESUMEN

Introduction. Laboratories worldwide are facing high demand for molecular testing during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, which might be further aggravated by the upcoming influenza season in the northern hemisphere.Gap Statement. Given that the symptoms of influenza are largely indistinguishable from those of coronavirus disease 2019 (COVID-19), both SARS-CoV-2 and the influenza viruses require concurrent testing by RT-PCR in patients presenting with symptoms of respiratory tract infection.Aim. We adapted and evaluated a laboratory-developed multiplex RT-PCR assay for simultaneous detection of SARS-CoV-2 (dual target), influenza A and influenza B (SC2/InflA/InflB-UCT) on a fully automated high-throughput system (cobas6800).Methodology. Analytical performance was assessed by serial dilution of quantified reference material and cell culture stocks in transport medium, including pretreatment for chemical inactivation. For clinical evaluation, residual portions of 164 predetermined patient samples containing SARS-CoV-2 (n=52), influenza A (n=43) or influenza B (n=19), as well as a set of negative samples, were subjected to the novel multiplex assay.Results. The assay demonstrated comparable analytical performance to currently available commercial tests, with limits of detection of 94.9 cp ml-1 for SARS-CoV-2, 14.6 cp ml-1 for influenza A and 422.3 cp ml-1 for influenza B. Clinical evaluation showed excellent agreement with the comparator assays (sensitivity of 98.1, 97.7 and 100 % for Sars-CoV-2 and influenza A and B, respectively).Conclusion. The SC2/InflA/InflB-UCT allows for efficient high-throughput testing for all three pathogens and thus provides streamlined diagnostics while conserving resources during the influenza season.


Asunto(s)
/métodos , Virus de la Influenza A/genética , Virus de la Influenza B/genética , Gripe Humana/diagnóstico , /genética , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/virología , Límite de Detección , Técnicas de Diagnóstico Molecular/métodos , Reacción en Cadena de la Polimerasa Multiplex , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad
5.
Emerg Infect Dis ; 27(1)2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33327991

RESUMEN

Analyses of infection chains have demonstrated that severe acute respiratory syndrome coronavirus 2 is highly transmissive. However, data on postmortem stability and infectivity are lacking. Our finding of nasopharyngeal viral RNA stability in 79 corpses showed no time-dependent decrease. Maintained infectivity is supported by virus isolation up to 35 hours postmortem.


Asunto(s)
/virología , Nasofaringe/virología , ARN Viral/aislamiento & purificación , Mucosa Respiratoria/virología , /aislamiento & purificación , Cadáver , Humanos
7.
J Clin Virol ; 132: 104650, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33011643

RESUMEN

BACKGROUND: The ongoing SARS-CoV-2 pandemic presents a unique challenge to diagnostic laboratories. There are preliminary studies correlating qRT-PCR results from different materials to clinical outcomes, yet, comparability is limited due to the plethora of different assays used for diagnostics. In this study we evaluate clinical performance and linear range for the SARS-CoV-2 IVD (cobas6800/8800 system, a fully automated sample-to-result platform) in different clinically relevant matrix materials outside official specifications. METHODS: Assay performance was assessed in human plasma, BAL/BL and transport medium following chemical inactivation. For analytical evaluation, respective matrix materials were spiked with SARS-CoV-2 RNA in ten-fold dilution series. The efficacy of chemical inactivation by guanidine hydrochloride solution was confirmed in cell culture infectivity experiments. For correlation, a total of 289 predetermined clinical samples including respiratory swabs, plasma and lower respiratory tract specimens were subjected to the SARS-CoV-2 IVD test and results were compared. RESULTS: The SARS-CoV-2 IVD showed excellent linearity over four to six log steps depending on matrix material. Chemical inactivation resulted in a reduction in plaque forming units of at least 3.5 log steps, while having no significant impact on assay performance. Inter-run consistency from three different testing sites demonstrated excellent comparability of RT-PCR results (maximum deviation was 1.53 CT). Clinical evaluation for respiratory swabs showed very good agreement with the comparator assay (Positive agreement 95.7 %, negative agreement 98.9 %). CONCLUSION: The SARS-CoV-2 IVD test for the cobas6800/8800 systems offers excellent linear range and inter-run consistency for quantification of SARS-CoV-2 RNA in different matrices outside official specifications.

9.
J Clin Virol ; 130: 104549, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32763809

RESUMEN

BACKGROUND: The global market for SARS-CoV-2-immunoassays is becoming ever more crowded with antibody-tests of various formats, targets and technologies, careful evaluation is crucial for understanding the implications of individual test results. Here, we evaluate the clinical performance of five automated immunoassays on a set of clinical samples. METHODS: Serum/plasma samples of 75 confirmed COVID-19 patients and 320 pre-pandemic serum samples of healthy blood donors were subjected to two IgG and three total antibody SARS-CoV-2-immunoassays. All test setups were automated workflows. RESULTS: Positivity of assays (onset of symptoms > 10 days) ranged between 68.4 % and 81.6 % (Diasorin 68.4 %, Euroimmun 70.3 %, Siemens 73.7 %, Roche 79.0 % and Wantai 81.6 %). All examined assays demonstrated high specificity of >99 % (Euroimmun, Diasorin: 99.1 %, Wantai: 99.4 %) but only two reached levels above 99.5 % (Roche: 99.7 %, Siemens 100 %). Interestingly, there was no overlap in false positive results between the assays. The strongest correlation of quantitative results was observed between the Diasorin and Euroimmun IgG tests (r2 = 0.76). Overall, we observed no difference in the distribution of test results between female and male patients (p-values: 0.18-0.87). A significant difference between severely versus critically ill patients was demonstrated for the Euroimmun, Diasorin, Wantai and Siemens assays (p-values:0.041). CONCLUSION: All assays showed good clinical performance. Our data confirm that orthogonal test strategies as recommended by the CDC can enhance clinical specificity. However, the suboptimal rates of test positivity found at time of hospitalization in this cohort underline the importance of molecular diagnostics to rule out/confirm active infection with SARS-CoV-2.


Asunto(s)
Anticuerpos Antivirales/sangre , Infecciones por Coronavirus/diagnóstico , Neumonía Viral/diagnóstico , Pruebas Serológicas/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Automatización de Laboratorios , Betacoronavirus , Técnicas de Laboratorio Clínico , Estudios de Cohortes , Infecciones por Coronavirus/inmunología , Reacciones Falso Positivas , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/inmunología , Sensibilidad y Especificidad , Adulto Joven
10.
Virchows Arch ; 477(3): 335-339, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32666230

RESUMEN

Clinical characterization of COVID-19 (Corona Virus Disease 2019) is being performed worldwide to gain insights into the pathogenesis and course of the disease. Little is known regarding morphological findings, which are essential to understanding the unique features and pathomechanisms of the disease, from which one can identify possible new treatments. It has been shown that diffuse alveolar damage, signifying acute respiratory distress syndrome, is present together with atypical multinucleated cells in reported cases of the disease by Tian et al. (J Thorac Oncol 15:700-704, 2020). Macroscopic morphological findings in COVID-19 remain elusive to this day. Here, we report the case of the first German to die due to COVID-19. A detailed examination consisting of full-body computed tomography, autopsy, histology assessment, and viral assessment has been performed. The lungs of the deceased contained high concentrations of SARS-CoV-2 RNA and displayed the typical radiological signatures of COVID-19. Furthermore, a morphological pattern was found displaying hyperaemic areas interspersed by normally perfused areas affecting the whole lung. We also report a finding suggestive of micro-thrombotic events in the lung, which is compatible with the recently described coagulation changes and increased incidence of pulmonary artery embolisms seen in COVID-19 patients as reported by Wichmann et al. (Ann Intern Med, 2020). A broader study is needed to confirm these findings.


Asunto(s)
Infecciones por Coronavirus/patología , Enfermedades Pulmonares/patología , Enfermedades Pulmonares/virología , Neumonía Viral/patología , Alveolos Pulmonares/patología , Autopsia , Betacoronavirus , Alemania , Humanos , Masculino , Persona de Mediana Edad , Pandemias , Trombosis/patología , Trombosis/virología
11.
Microbiol Resour Announc ; 9(23)2020 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-32499358

RESUMEN

Here, we describe the complete genome sequence of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain isolated from an oropharyngeal swab sample from a female patient with COVID-19 who was infected in Hamburg, northern Germany.

12.
J Clin Virol ; 128: 104390, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32388471

RESUMEN

BACKGROUND: The ongoing SARS-CoV-2 pandemic presents a unique challenge for diagnostic laboratories around the world. Automation of workflows in molecular diagnostics is instrumental for coping with the large number of tests ordered by clinicians, as well as providing fast-tracked rapid testing for highly urgent cases. In this study we evaluated a SARS-CoV-2 LDT for the NeuMoDx 96 system, a fully automated device performing extraction and real-time PCR. METHODS: A publicly available SARS-CoV-2 RT-PCR assay was adapted for the automated system. Analytical performance was evaluated using in-vitro transcribed RNA and clinical performance was compared to the cobas 6800-based reference assay within the lab. RESULTS: The Envelope (E) Gene-LDT displayed good analytical performance with an LoD of 95.55 cp/mL and no false positives during evaluation of cross-reactivity. A total of 176 patient samples were tested with both the E-Gene-LDT and the reference assay. Positive and negative agreement were 100 % and 99.2 % respectively. Invalid-rate was 6.3 %. CONCLUSION: The E-Gene-LDT showed analytical and clinical performance comparable to the cobas6800-based reference assay. Due to its random-access workflow concept and rapid time-to-result of about 80 min, the system is very well suited for providing fast-tracked SARS-CoV-2 diagnostics for urgent clinical samples in the hospital setting.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Pandemias , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , Betacoronavirus , Técnicas de Laboratorio Clínico/instrumentación , Infecciones por Coronavirus/diagnóstico , Hospitales , Humanos , Neumonía Viral , Reacción en Cadena en Tiempo Real de la Polimerasa/instrumentación , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/instrumentación , Factores de Tiempo , Flujo de Trabajo
13.
J Microbiol Methods ; 172: 105882, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32119956

RESUMEN

BACKGROUND: The cobas® omni Utility Channel enables users to integrate lab-developed tests (LDTs) on the cobas® 6800 System to perform molecular diagnostics with high-throughput capacity and full automation. At present, there are no CE- or FDA-approved tests for stool pathogens on this system. To assess the performance of stool as a matrix, we evaluated the analytical and clinical performance of an LDT for detection of Clostridioides difficile (C. difficile) toxin B using the Utility Channel (C.diff_UTC). METHODS: A 10% stool suspension prepared from liquid stool samples diluted in phosphate buffered saline was used for analysis. Limit of detection (LoD) was determined in six dilutions with 126 replicates/dilution. Clinical evaluation was performed using 514 predetermined patient stool samples from two study sites in Germany. The C.diff_UTC was compared with LC 480 amplification and an LDT or the R-BioPharm C. difficile assay. Discrepant results were further analyzed using the GeneXpert C. difficile assay. RESULTS: Limit of detection was 23.48 cfu/mL (95% Confidence Interval [CI]: 19.14-31.01) with inter-run variation of <2 cycle thresholds at 3 × and 10 × LoD. No cross-reactivity was observed with a panel of fecal organisms and pathogens. Bioinformatic analysis showed coverage of the major C. difficile toxinotypes by the primer/probe set. Clinical evaluation revealed sensitivity of 96.7% (95% CI: 88.7-99.6) and specificity of 99.3% (95% CI: 98.0-99.9) compared with the reference method; inhibition rate was 3.5% (18/514). CONCLUSION: Using a predesigned primer/probe set, the C.diff_UTC assay features analytical performance and clinical sensitivity and specificity comparable to currently available nucleic acid amplification tests (NAATs) and is suitable for high-throughput testing. This was a proof-of-concept study, indicating the cobas Utility Channel could likely be adapted for other clinically relevant stool pathogens in outbreak scenarios.

14.
PLoS One ; 11(1): e0146370, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26741489

RESUMEN

BACKGROUND: Treatment of breast cancer patients with distant metastases represents one of the biggest challenges in today's gynecological oncology. Therefore, a better understanding of mechanisms promoting the development of metastases is of paramount importance. The serine/threonine kinase AKT was shown to drive cancer progression and metastasis. However, there is emerging data that single AKT isoforms (i.e. AKT1, AKT2 and AKT3) have different or even opposing functions in the regulation of cancer cell migration in vitro, giving rise to the hypothesis that inhibition of distinct AKT isoforms might have undesirable effects on cancer dissemination in vivo. METHODS: The triple negative breast cancer cell line MDA-MB-231 was used to investigate the functional roles of AKT in migration and metastasis. AKT single and double knockdown cells were generated using isoform specific shRNAs. Migration was analyzed using live cell imaging, chemotaxis and transwell assays. The metastatic potential of AKT isoform knockdown cells was evaluated in a subcutaneous xenograft mouse model in vivo. RESULTS: Depletion of AKT3, but not AKT1 or AKT2, resulted in increased migration in vitro. This effect was even more prominent in AKT2,3 double knockdown cells. Furthermore, combined downregulation of AKT2 and AKT3, as well as AKT1 and AKT3 significantly increased metastasis formation in vivo. Screening for promigratory proteins revealed that downregulation of AKT3 increases the expression of S100A4 protein. In accordance, depletion of S100A4 by siRNA approach reverses the increased migration induced by knockdown of AKT3. CONCLUSIONS: We demonstrated that knockdown of AKT3 can increase the metastatic potential of triple negative breast cancer cells. Therefore, our results provide a rationale for the development of AKT isoform specific inhibitors.


Asunto(s)
Adenocarcinoma/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas S100/genética , Neoplasias de la Mama Triple Negativas/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/secundario , Animales , Línea Celular Tumoral , Movimiento Celular , Quimiotaxis/genética , Cámaras de Difusión de Cultivos , Femenino , Silenciador del Gen , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/secundario , Ratones , Invasividad Neoplásica , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Proteína de Unión al Calcio S100A4 , Proteínas S100/agonistas , Proteínas S100/metabolismo , Transducción de Señal , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
15.
J Cancer ; 6(12): 1195-205, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26535060

RESUMEN

Hepatocellular carcinoma (HCC) is the sixth most common cancer, and the third most common cause of cancer related death worldwide. The multi-kinase inhibitor Sorafenib represents the only systemic treatment option until today, and results from clinical trials with allosteric mTOR inhibitors were sobering. Since the PI3K/AKT/mTOR and RAF/MEK/ERK signaling pathways are frequently upregulated in HCC, we have analyzed the effects of AKT inhibitor MK-2206, MEK inhibitor AZD6244 (ARRY 142886) and mTOR kinase inhibitor AZD8055, given as single drugs or in combination, on proliferation and apoptosis of three HCC cell lines in vitro. We show that all three inhibitor combinations synergistically inhibit proliferation of the three HCC cell lines, with the strongest synergistic effect observed after vertical inhibition of AKT and mTORC1/2. We demonstrate that AKT kinase activity is restored 24h after blockade of mTORC1/2 by increased phosphorylation of T308, providing a rationale for combined targeting of AKT and mTOR inhibition in HCC. Our data suggest that a combination of inhibitors targeting those respective pathways may be a viable approach for future application in patients with hepatocellular carcinoma.

16.
Cell Signal ; 27(11): 2191-200, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26210887

RESUMEN

BACKGROUND: Development of small molecular inhibitors against BRAF and MEK has been a breakthrough in the treatment of malignant melanoma. However, the long-term effect is foiled in virtually all patients by the emergence of resistant tumor cell populations. Therefore, mechanisms resulting in the acquired resistance against BRAF and MEK inhibitors have gained much attention and several strategies have been proposed to overcome tumor resistance, including interval treatment or withdrawal of these compounds after disease progression. METHODS: Using a panel of cell lines with an acquired resistance against MEK inhibitors, we have evaluated the sensitivity of these cells against compounds targeting AKT/mTOR signaling, as well as novel ERK1/2 inhibitors. Furthermore, the effects of withdrawal of MEK inhibitor on migration in resistant cell lines were analyzed. RESULTS: We demonstrate that withdrawal of BRAF or MEK inhibitors in tumor cells with an acquired resistance results in reactivation of ERK1/2 signaling and upregulation of EMT-inducing transcription factors, leading to a highly migratory and invasive phenotype of cancer cells. Furthermore, we show that migration in these cells is independent from AKT/mTOR signaling. However, combined targeting of AKT/mTOR using MK-2206 and AZD8055 efficiently inhibits proliferation in all resistant tumor cell lines analyzed. CONCLUSIONS: We propose that combined targeting of MEK/AKT/mTOR or treatment with a novel ERK1/2 inhibitor downstream of BRAF/MEK suppresses proliferation as well as migration and invasion in resistant tumor cells. We provide a rationale against the discontinuation of BRAF or MEK inhibitors in patients with an acquired resistance, and provide a rationale for combined targeting of AKT/mTOR and MEK/ERK1/2, or direct targeting of ERK1/2 as an effective treatment strategy.


Asunto(s)
Movimiento Celular/efectos de los fármacos , Melanoma/tratamiento farmacológico , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Invasividad Neoplásica/patología , Inhibidores de Proteínas Quinasas/farmacología , Bencimidazoles/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Resistencia a Antineoplásicos , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Células HCT116 , Células HT29 , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Morfolinas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Proteína S6 Ribosómica/metabolismo , Transducción de Señal/efectos de los fármacos , Neoplasias Cutáneas , Serina-Treonina Quinasas TOR/antagonistas & inhibidores
17.
Invest New Drugs ; 32(6): 1144-54, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25152244

RESUMEN

UNLABELLED: Until today, there is no systemic treatment available for advanced cholangiocarcinoma (CCA). Recent studies have shown a frequent upregulation of the PI3K-AKT-mTOR and RAF-MEK-ERK pathways in this type of cancer. However, considering their high extend of redundancy and cross-talk, targeting only one pathway is likely to result in therapy failure and emergence of resistances. To provide a rationale for treatment of CCA with inhibitors of these respective pathways, we analyzed the effects of AKT inhibitor MK-2206, MEK inhibitor AZD6244 (ARRY-142886) and mTOR kinase inhibitor AZD8055 on three CCA cell lines in vitro, concerning proliferation, cell signaling and apoptosis. Furthermore, AZD6244 resistant cell lines have been generated to investigate, how their response may be affected by prolonged treatment with only a single inhibitor. Our data demonstrates that co-targeting of both, the PI3K/AKT/mTOR and RAF-MEK-ERK pathway, as well as vertical targeting of AKT and mTOR results in strong synergistic effects on proliferation and cell survival with combination indices below 0.3. Mechanistically, the combinatorial treatment with MK-2206 in addition to AZD8055 is necessary because AKT kinase activity was quickly restored after mTOR kinase inhibition. Interestingly, acquired MEK inhibitor resistance to AZD6244 was reversed by combined treatment with AZD6244 and either MK-2206 or AZD8055. Our data suggest that a combination of inhibitors targeting those respective pathways may be a viable approach for future application in patients with cholangiocarcinoma. IMPLICATIONS: AKT, mTOR and MEK are promising targets for a combinatorial treatment of cholangiocarcinoma cells even after acquisition of MEK inhibitor resistance.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias de los Conductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Bencimidazoles/farmacología , Conductos Biliares Intrahepáticos/metabolismo , Proliferación Celular/efectos de los fármacos , Resistencia a Antineoplásicos , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Compuestos Heterocíclicos con 3 Anillos/farmacología , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Morfolinas/farmacología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Quinasas raf/antagonistas & inhibidores
18.
Int J Cancer ; 133(9): 2065-76, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23588885

RESUMEN

Cholangiocarcinoma (CCA) is a rare, but devastating disease arising from the epithelium of intrahepatic and extrahepatic bile ducts. There are neither effective systemic therapies nor satisfying treatment options for inoperable CCA. Histopathological and biochemical studies of CCA show frequent dysregulation of the phosphatidylinositol 3-kinase/AKT/mammalian target of rapamycin (mTOR) pathway. Therefore, we investigated the efficacy of the mTOR inhibitor RAD001 and the impact of AKT signaling following mTOR inhibition in the treatment of CCA. RAD001 significantly inhibits proliferation of CCA cell lines, however, a concentration-dependent and isoform specific feedback activation of the three AKT isoforms (AKT1, AKT2 and AKT3) was observed after mTOR inhibition. As activation of AKT might limit the RAD001-mediated anti-tumor effect, the efficacy of combined mTOR and AKT inhibition was investigated using the allosteric AKT inhibitor MK-2206. Our results show that inhibition of AKT potentiates the efficacy of mTOR inhibition both in vitro and in a xenograft mouse model in vivo. Mechanistically, the antiproliferative effect of the pan-AKT inhibitor MK2206 in the CCA cell line TFK-1 was due to inhibition of AKT1 and AKT2, because knockdown of either AKT1 or AKT2, but not AKT3, showed a synergistic reduction of cell proliferation in combination with mTOR treatment. Finally, using an AKT isoform specific in vitro kinase assay, enzymatic activity of each of the three AKT isoforms was detected in all tissue samples from CCA patients, analyzed. In summary, our preclinical data suggest that combined targeting of mTOR and AKT using RAD001 and MK-2206 might be a new, effective strategy for the treatment of CCA.


Asunto(s)
Neoplasias de los Conductos Biliares/tratamiento farmacológico , Conductos Biliares Intrahepáticos/efectos de los fármacos , Colangiocarcinoma/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Sirolimus/análogos & derivados , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/metabolismo , Conductos Biliares Intrahepáticos/patología , Western Blotting , Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Sinergismo Farmacológico , Everolimus , Citometría de Flujo , Humanos , Inmunoprecipitación , Ratones , Fosfatidilinositol 3-Quinasa/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Sirolimus/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
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