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1.
Histopathology ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39360579

RESUMO

AIMS: To create and validate a weakly supervised artificial intelligence (AI) model for detection of abnormal colorectal histology, including dysplasia and cancer, and prioritise biopsies according to clinical significance (severity of diagnosis). MATERIALS AND METHODS: Triagnexia Colorectal, a weakly supervised deep learning model, was developed for the classification of colorectal samples from haematoxylin and eosin (H&E)-stained whole slide images. The model was trained on 24 983 digitised images and assessed by multiple pathologists in a simulated digital pathology environment. The AI application was implemented as part of a point and click graphical user interface to streamline decision-making. Pathologists assessed the accuracy of the AI tool, its value, ease of use and integration into the digital pathology workflow. RESULTS: Validation of the model was conducted on two cohorts: the first, on 100 single-slide cases, achieved micro-average model specificity of 0.984, micro-average model sensitivity of 0.949 and micro-average model F1 score of 0.949 across all classes. A secondary multi-institutional validation cohort, of 101 single-slide cases, achieved micro-average model specificity of 0.978, micro-average model sensitivity of 0.931 and micro-average model F1 score of 0.931 across all classes. Pathologists reflected their positive impressions on the overall accuracy of the AI in detecting colorectal pathology abnormalities. CONCLUSIONS: We have developed a high-performing colorectal biopsy AI triage model that can be integrated into a routine digital pathology workflow to assist pathologists in prioritising cases and identifying cases with dysplasia/cancer versus non-neoplastic biopsies.

2.
BMC Cancer ; 20(1): 641, 2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32650756

RESUMO

BACKGROUND: The COVID-19 pandemic has caused a global health crisis. Numerous cancer patients from non-Western countries, including the United Arab Emirates (UAE), seek cancer care outside their home countries and many are sponsored by their governments for treatment. Many patients interrupted their cancer treatment abruptly and so returned to their home countries with unique challenges. In this review we will discuss practical challenges and recommendations for all cancer patients returning to their home countries from treatment abroad. METHOD: Experts from medical, surgical and other cancer subspecialties in the UAE were invited to form a taskforce to address challenges and propose recommendations for patients returning home from abroad after medical tourism during the SARS-COV-19 Pandemic. RESULTS: The taskforce which consisted of experts from medical oncology, hematology, surgical oncology, radiation oncology, pathology, radiology and palliative care summarized the current challenges and suggested a practical approaches to address these specific challenges to improve the returning cancer patients care. Lack of medical documentation, pathology specimens and radiology images are one of the major limitations on the continuation of the cancer care for returning patients. Difference in approaches and treatment recommendations between the existing treating oncologists abroad and receiving oncologists in the UAE regarding the optimal management which can be addressed by early and empathic communications with patients and by engaging the previous treating oncologists in treatment planning based on the available resources and expertise in the UAE. Interruption of curative radiotherapy (RT) schedules which can potentially increase risk of treatment failure has been a major challenge, RT dose-compensation calculation should be considered in these circumstances. CONCLUSION: The importance of a thorough clinical handover cannot be overstated and regulatory bodies are needed to prevent what can be considered unethical procedure towards returning cancer patients with lack of an effective handover. Clear communication is paramount to gain the trust of returning patients and their families. This pandemic may also serve as an opportunity to encourage patients to receive treatment locally in their home country. Future studies will be needed to address the steps to retain cancer patients in the UAE rather than seeking cancer treatment abroad.


Assuntos
Continuidade da Assistência ao Paciente/normas , Infecções por Coronavirus/epidemiologia , Oncologia/normas , Turismo Médico , Neoplasias/terapia , Pneumonia Viral/epidemiologia , Comitês Consultivos , Betacoronavirus , COVID-19 , Consenso , Humanos , Oncologia/organização & administração , Pandemias , SARS-CoV-2 , Emirados Árabes Unidos
3.
Int J Cancer ; 138(1): 195-205, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26152787

RESUMO

Dysregulation of the Notch1 receptor has been shown to facilitate the development and progression of colorectal cancer (CRC) and has been identified as an independent predictor of disease progression and worse survival. Although mutations in the NOTCH1 receptor have not been described in CRC, we have previously discovered a NOTCH1 gene copy number gain in a portion of CRC tumor samples. Here, we demonstrated that a NOTCH1 gene copy number gain is significantly associated with worse survival and a high percentage of gene duplication in a cohort of patients with advanced CRC. In our CRC patient-derived tumor xenograft (PDTX) model, tumors harboring a NOTCH1 gain exhibited significant elevation of the Notch1 receptor, JAG1 ligand and cleaved Notch1 activity. In addition, a significant association was identified between a gain in NOTCH1 gene copy number and sensitivity to a Notch1-targeting antibody. These findings suggest that patients with metastatic CRC that harbor a gain in NOTCH1 gene copy number have worse survival and that targeting this patient population with a Notch1 antibody may yield improved outcomes.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Variações do Número de Cópias de DNA , Dosagem de Genes , Receptor Notch1/genética , Animais , Anticorpos Monoclonais/farmacologia , Apoptose/efeitos dos fármacos , Apoptose/genética , Biomarcadores Tumorais , Proteínas de Ligação ao Cálcio/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Duplicação Gênica , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteína Jagged-1 , Masculino , Proteínas de Membrana/metabolismo , Camundongos , Metástase Neoplásica , Prognóstico , Receptor Notch1/antagonistas & inibidores , Receptor Notch1/metabolismo , Proteínas Serrate-Jagged , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
JOP ; 15(5): 515-9, 2014 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-25262725

RESUMO

CONTEXT: Papillary gallbladder adenocarcinoma (PGA) represents 5% of malignant gallbladder tumors. Metastatic disease frequently involves lymph nodes or other structures in the hepatoduodenal ligament. CASE REPORT: A Fifty-nine-year-old female with right upper quadrant pain and a giant gallbladder on ultrasound was found to have a segment 6 liver lesion during an attempted laparoscopic cholecystectomy. After appropriate staging, she underwent an open cholecystectomy and extended right hepatic lobectomy with portal lymph node dissection. Pathology demonstrated well-to-moderately differentiated PGA with identical morphology and immunohistochemistry in the liver resection specimen with negative margins. Despite adjuvant chemotherapy, she developed increased uptake in the head of the pancreas on PET scan. Endoscopic ultrasound with fine needle aspiration demonstrated metastatic PGA. She underwent an attempted Whipple operation but due to repeatedly positive pancreatic duct margins, she ended up with a total pancreatectomy and splenectomy. Final pathology showed metastatic PGA along the entire length of the pancreatic duct with only a single focus of tumor invasion into the pancreatic parenchyma. She developed a new liver metastases six months later that was unresponsive to FOLFOX therapy and she died of metastatic disease 33 months from her initial diagnosis. CONCLUSION: To our knowledge, this is the first report of metastatic PGA recurring along the entire pancreatic duct with disease confined to the pancreas only. We hypothesize that papillary tumor cells spread to pancreatic duct via the common bile duct and remained dormant for several years. An aggressive surgical approach may prolong survival in well-selected patients with PGA's.

5.
Proc Natl Acad Sci U S A ; 108(40): 16711-6, 2011 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-21873195

RESUMO

IL-37, a newly described member of the IL-1 family, functions as a fundamental inhibitor of innate inflammation and immunity. In the present study, we examined a role for IL-37 during experimental colitis. A transgenic mouse strain was generated to express human IL-37 (hIL-37tg), and these mice were subjected to dextran sulfate sodium (DSS)-induced colitis. Despite the presence of a CMV promoter to drive expression of IL-37, mRNA transcripts were not present in colons at the resting state. Expression was observed only upon disruption of the epithelial barrier, with a six- to sevenfold increase (P = 0.02) on days 3 and 5 after continuous exposure to DSS. During the development of colitis, clinical disease scores were reduced by 50% (P < 0.001), and histological indices of colitis were one-third less in hIL-37tg mice compared with WT counterparts (P < 0.001). Reduced inflammation was associated with decreased leukocyte recruitment into the colonic lamina propria. In addition, release of IL-1ß and TNFα from ex vivo colonic explant tissue was decreased 5- and 13-fold, respectively, compared with WT (P ≤ 0.005), whereas IL-10 was increased sixfold (P < 0.001). However, IL-10 was not required for the anti-inflammatory effects of IL-37 because IL-10-receptor antibody blockade did not reverse IL-37-mediated protection. Mechanistically, IL-37 originating from hematopoietic cells was sufficient to exert anti-inflammatory effects because WT mice reconstituted with hIL-37tg bone marrow were protected from colitis. Thus, IL-37 emerges as key modulator of intestinal inflammation.


Assuntos
Colite/imunologia , Interleucina-1/metabolismo , Análise de Variância , Animais , Colite/patologia , Sulfato de Dextrana , Citometria de Fluxo , Humanos , Interleucina-1/imunologia , Interleucina-1beta/metabolismo , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismo
6.
Invest New Drugs ; 31(2): 345-54, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22615057

RESUMO

Background This phase Ib study was designed to determine the maximum tolerated doses (MTD) and dose limiting toxicities (DLTs) of irinotecan and cetuximab with sorafenib. Secondary objectives included characterizing the pharmacokinetics and pharmacodynamics and evaluating preliminary antitumor activity in patients with advanced colorectal cancer (CRC). Methods Patients with metastatic, pretreated CRC were treated at five dose levels. Results Eighteen patients were recruited with median age 56.5 years. In the first five patients treated, 2 irinotecan related DLTs were observed. With reduced dose intensity irinotecan, there were no further DLTs. The most common toxicities were diarrhea, nausea/vomiting, fatigue, anorexia and rash. DLTs included neutropenia and thrombocytopenia. Two patients had partial responses (one with a KRAS mutation) and 8 had stable disease (8-36 weeks). The median progression free survival (PFS) and overall survival (OS) were 2.5 and 4.7 months respectively. Pharmacokinetic analyses suggest sorafenib and metabolite exposure correlate with OS and DLTs. Conclusions The recommended phase II dose (RP2D) is irinotecan 100 mg/m(2) i.v. days 1, 8; cetuximab 400 mg/m(2) i.v. days 1 and 250 mg/m(2) i.v. weekly; and sorafenib 400 mg orally twice daily in advanced, pretreated CRC. The combination resulted in a modest response rate.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Cetuximab , Relação Dose-Resposta a Droga , Feminino , Humanos , Irinotecano , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/análogos & derivados , Compostos de Fenilureia/administração & dosagem , Prognóstico , Sorafenibe , Distribuição Tecidual
7.
JOP ; 14(1): 77-80, 2013 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-23306340

RESUMO

CONTEXT: Cystic tumors of the pancreas have been diagnosed with increasing frequency. Intraductal oncocytic papillary neoplasm is a rare type of cystic pancreatic tumor. Intraductal oncocytic papillary neoplasm is considered a distinct entity with the potential of developing into invasive carcinoma and it should be differentiated from other cystic tumors of the pancreas, including mucinous cystic neoplasm and other forms of intraductal papillary mucinous neoplasm (IPMN). Histologically, the formation of oncocytic cells and the complex morphology of the papillae distinguish intraductal oncocytic papillary neoplasm from IPMN. While the number of publications addressing the diagnosis, management and follow-up of patients with IPMN has been increasing, the behavior differences between IPMN and intraductal oncocytic papillary neoplasm have not been elucidated, secondary to very limited clinical experience. CASE REPORT: Here, we are presenting a case of a patient with the diagnosis of intraductal oncocytic papillary neoplasm of the pancreas developing into invasive cancer. CONCLUSION: This case stresses the necessity for lifelong surveillance of the remnant pancreas following partial pancreatectomy for intraductal oncocytic papillary neoplasm, due to the risk of developing multifocal disease.


Assuntos
Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Papilar/diagnóstico , Ductos Pancreáticos/patologia , Neoplasias Pancreáticas/diagnóstico , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Papilar/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Pancreatectomia , Ductos Pancreáticos/cirurgia , Neoplasias Pancreáticas/cirurgia , Resultado do Tratamento
8.
JOP ; 14(3): 289-91, 2013 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-23669483

RESUMO

CONTEXT: Anaplastic pancreatic carcinoma is a rare tumor with poor survival. Data on surgical and medical therapies are currently limited to case reports and case series with small numbers. CASE REPORT: We describe a case of multifocal anaplastic pancreatic carcinoma treated with neoadjuvant FOLFIRINOX (oxaliplatin, irinotecan, fluorouracil and leucovorin) and total pancreatectomy with subsequent patient disease-free survival currently at 12 months. DISCUSSION: The goal for anaplastic pancreatic carcinoma treatment should continue to be complete surgical resection. Optimum chemotherapeutic options continue to be investigated.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/terapia , Pancreatectomia/métodos , Neoplasias Pancreáticas/terapia , Camptotecina/administração & dosagem , Camptotecina/análogos & derivados , Carcinoma/patologia , Terapia Combinada , Fluoruracila/administração & dosagem , Humanos , Irinotecano , Leucovorina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Neoplasias Pancreáticas/patologia , Resultado do Tratamento
9.
JOP ; 13(5): 536-9, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22964962

RESUMO

CONTEXT: Ampullary adenocarcinomas and bile duct cancers represent a very small minority of all gastrointestinal malignancies. Synchronous presentation of both malignancies is extremely rare. CASE REPORT: We report a case of a 76-year-old male who presented with painless jaundice. His work-up showed an ampullary mass and a separate common bile duct stricture. Attempted endoscopic resection established the diagnosis of ampullary adenocarcinoma. Pathologic examination of the Whipple specimen identified a separate focus of bile duct cancer. CONCLUSION: Synchronous presentation of an ampullary mass and separate distal bile duct stricture, especially in elderly patients, should raise concern for both lesions representing malignancies. In the absence of conclusive evidence for survival advantage in resected early stage ampullary and biliary cancers, close observation should be considered a valid alternative to adjuvant chemotherapy and radiation.


Assuntos
Adenocarcinoma/diagnóstico , Ampola Hepatopancreática , Neoplasias do Ducto Colédoco/diagnóstico , Neoplasias Duodenais/diagnóstico , Neoplasias Primárias Múltiplas/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino
10.
Oncology (Williston Park) ; 24(14): 1329-34, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21294478

RESUMO

The patient is a 57-year old Caucasian female who presented with right upper quadrant pain and obstructive jaundice and was diagnosed with resectable pancreatic cancer. She underwent pancreaticoduodenectomy (PD) after preoperative biliary stenting. She subsequently presented to the clinic, where it was noticed that she had an elevated CA 19-9. CT C/A/P revealed multiple new liver lesions.


Assuntos
Adenocarcinoma/cirurgia , Neoplasias Hepáticas/secundário , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Antígeno CA-19-9/sangue , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Tomografia Computadorizada por Raios X
11.
Gulf J Oncolog ; 1(32): 71-87, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32342923

RESUMO

With cancer being the third leading cause of mortality in the United Arab Emirates (UAE), there has been significant investment from the government and private health care providers to enhance the quality of cancer care in the UAE. The UAE is a developing country with solid economic resources that can be utilized to improve cancer care across the country. There is limited data regarding the incidence, survival, and potential risk factors for cancer in the UAE. The UAE Oncology Task Force was established in 2019 by cancer care providers from across the UAE under the auspices of Emirates Oncology Society. In this paper we summarize the history of cancer care in the UAE, report the national cancer incidence, and outline current challenges and opportunities to enhance and standardize cancer care. We provide recommendations for policymakers and the UAE Oncology community for the delivery of high-quality cancer care. These recommendations are aligned with the UAE government's vision to reduce cancer mortality and provide high quality healthcare for its citizens.


Assuntos
Neoplasias/epidemiologia , História do Século XXI , Humanos , Emirados Árabes Unidos
14.
Case Reports Immunol ; 2018: 7435870, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30510820

RESUMO

A 27-year-old Emirate man presented to Cleveland Clinic Abu Dhabi emergency department with a 4 year history of recurrent episodes of severe swellings affecting different parts of his body. He used to get 2 swelling episodes every week affecting either his face, hands, feet or scrotum and severe abdominal pain twice a week. Abdominal CT scan and a colonoscopy showed bowel wall oedema. There was no family history of similar complaint or of hereditary angioedema (HAE). Complement studies confirmed the diagnosis of HAE type II. He was commenced on danazol 100 mg twice daily and his symptoms resolved. This case report highlights the importance of considering HAE in patients with recurrent unexplained abdominal pain even in the absence of positive family history of HAE.

15.
Case Rep Surg ; 2015: 157613, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25874152

RESUMO

A twenty-five-year-old female presented with a large retroperitoneal mass. Workup included history and physical exam, imaging, biopsy, colonoscopy, and gynecologic exam. After surgical resection, the mass was determined to be a primary retroperitoneal mucinous tumor (PRMT). Clinically and histologically, these tumors are similar pancreatic and ovarian mucinous neoplasms. PRMTs are rare and few case reports have been published. PRMTs are divided into mucinous cystadenomas, mucinous borderline tumors of low malignant potential, and mucinous carcinoma. These tumors have malignant potential so resection is indicated and in some cases adjuvant chemotherapy and/or surveillance imaging.

16.
Clin Cancer Res ; 19(22): 6219-29, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24045180

RESUMO

PURPOSE: Results from clinical trials involving resistance to molecularly targeted therapies have revealed the importance of rational single-agent and combination treatment strategies. In this study, we tested the efficacy of a type 1 insulin-like growth factor receptor (IGF1R)/insulin receptor (IR) tyrosine kinase inhibitor, OSI-906, in combination with a mitogen-activated protein (MAP)-ERK kinase (MEK) 1/2 inhibitor based on evidence that the MAP kinase pathway was upregulated in colorectal cancer cell lines that were resistant to OSI-906. EXPERIMENTAL DESIGN: The antiproliferative effects of OSI-906 and the MEK 1/2 inhibitor U0126 were analyzed both as single agents and in combination in 13 colorectal cancer cell lines in vitro. Apoptosis, downstream effector proteins, and cell cycle were also assessed. In addition, the efficacy of OSI-906 combined with the MEK 1/2 inhibitor selumetinib (AZD6244, ARRY-142886) was evaluated in vivo using human colorectal cancer xenograft models. RESULTS: The combination of OSI-906 and U0126 resulted in synergistic effects in 11 of 13 colorectal cancer cell lines tested. This synergy was variably associated with apoptosis or cell-cycle arrest in addition to molecular effects on prosurvival pathways. The synergy was also reflected in the in vivo xenograft studies following treatment with the combination of OSI-906 and selumetinib. CONCLUSIONS: Results from this study demonstrate synergistic antiproliferative effects in response to the combination of OSI-906 with an MEK 1/2 inhibitor in colorectal cancer cell line models both in vitro and in vivo, which supports the rational combination of OSI-906 with an MEK inhibitor in patients with colorectal cancer. Clin Cancer Res; 19(22); 6219-29. ©2013 AACR.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Imidazóis/farmacologia , Pirazinas/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Receptor de Insulina/antagonistas & inibidores , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose/efeitos dos fármacos , Benzimidazóis/farmacologia , Butadienos/farmacologia , Caspase 3/metabolismo , Caspase 7/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 2/antagonistas & inibidores , Camundongos , Camundongos Nus , Transplante de Neoplasias , Nitrilas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transplante Heterólogo
17.
Inflamm Bowel Dis ; 19(9): 1964-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23835442

RESUMO

BACKGROUND: Fecal alpha-1-antitrypsin (AAT) clearance has been a marker of clinical disease severity in inflammatory bowel diseases (IBDs) for many years. Although AAT deficiency is more often associated with lung and liver pathologies, AAT-deficient patients with concomitant IBD have been shown to develop more aggressive disease and rapid progression to surgery. Although recent studies have highlighted the pleiotropic anti-inflammatory functions of AAT, including reducing proinflammatory cytokine production and suppressing immune cell activation, its potential therapeutic role in IBD has not been described. METHODS: The therapeutic potential of human AAT administration was assessed in murine models of IBD including new-onset and established chemically induced colitis and spontaneous chronic murine ileitis. Histological assessment of inflammation, cytokine secretion profiling, and flow cytometric evaluation of inflammatory infiltrate were performed in each model. The effect of AAT on intestinal barrier function was also examined both in vitro and in vivo. RESULTS: AAT attenuated inflammation in small and large intestinal IBD models through reduced secretion of proinflammatory cytokines, inflammatory cell infiltration, and reduced tissue injury. AAT also increased intestinal restitution after chemically induced colitis. AAT significantly decreased intestinal permeability in vitro and in vivo as part of a protective mechanism for both acute and chronic models of IBD. CONCLUSIONS: Our findings describe a beneficial role for AAT in IBD models through suppression of cytokine production and enhanced intestinal barrier function. This raises the possibility that AAT supplementation, which has a long history of proven safety, may have a therapeutic effect in human IBD.


Assuntos
Colite/prevenção & controle , Sulfato de Dextrana/toxicidade , Ileíte/prevenção & controle , alfa 1-Antitripsina/uso terapêutico , Doença Aguda , Animais , Permeabilidade da Membrana Celular , Doença Crônica , Colite/induzido quimicamente , Colite/imunologia , Citocinas/metabolismo , Citometria de Fluxo , Humanos , Ileíte/induzido quimicamente , Ileíte/imunologia , Inflamação/etiologia , Inflamação/prevenção & controle , Camundongos
18.
Clin Cancer Res ; 19(15): 4149-62, 2013 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-23757356

RESUMO

PURPOSE: The mitogen-activated protein kinase (MAPK) pathway is a crucial regulator of cell proliferation, survival, and resistance to apoptosis. MEK inhibitors are being explored as a treatment option for patients with KRAS-mutant colorectal cancer who are not candidates for EGFR-directed therapies. Initial clinical results of MEK inhibitors have yielded limited single-agent activity in colorectal cancer, indicating that rational combination strategies are needed. EXPERIMENTAL DESIGN: In this study, we conducted unbiased gene set enrichment analysis and synthetic lethality screens with selumetinib, which identified the noncanonical Wnt/Ca++ signaling pathway as a potential mediator of resistance to the MEK1/2 inhibitor selumetinib. To test this, we used shRNA constructs against relevant WNT receptors and ligands resulting in increased responsiveness to selumetinib in colorectal cancer cell lines. Further, we evaluated the rational combination of selumetinib and WNT pathway modulators and showed synergistic antiproliferative effects in in vitro and in vivo models of colorectal cancer. RESULTS: Importantly, this combination not only showed tumor growth inhibition but also tumor regression in the more clinically relevant patient-derived tumor explant (PDTX) models of colorectal cancer. In mechanistic studies, we observed a trend toward increased markers of apoptosis in response to the combination of MEK and WntCa(++) inhibitors, which may explain the observed synergistic antitumor effects. CONCLUSIONS: These results strengthen the hypothesis that targeting both the MEK and Wnt pathways may be a clinically effective rational combination strategy for patients with metastatic colorectal cancer.


Assuntos
Benzimidazóis/administração & dosagem , Neoplasias Colorretais/tratamento farmacológico , Ciclosporina/administração & dosagem , Inibidores de Proteínas Quinases/administração & dosagem , Apoptose , Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Humanos , MAP Quinase Quinase Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Transdução de Sinais/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas ras/genética
19.
Cancer Med ; 1(2): 207-17, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23342270

RESUMO

Src tyrosine kinases are overexpressed in pancreatic cancers, and the oral Src inhibitor saracatinib has shown antitumor activity in preclinical models of pancreas cancer. We performed a CTEP-sponsored Phase II clinical trial of saracatinib in previously treated pancreas cancer patients, with a primary endpoint of 6-month survival. A Simon MinMax two-stage phase II design was used. Saracatinib (175 mg/day) was administered orally continuously in 28-day cycles. In the unselected portion of the study, 18 patients were evaluable. Only two (11%) patients survived for at least 6 months, and three 6-month survivors were required to move to second stage of study as originally designed. The study was amended as a biomarker-driven trial (leucine rich repeat containing protein 19 [LRRC19] > insulin-like growth factor-binding protein 2 [IGFBP2] "top scoring pairs" polymerase chain reaction [PCR] assay, and PIK3CA mutant) based on preclinical data in a human pancreas tumor explant model. In the biomarker study, archival tumor tissue or fresh tumor biopsies were tested. Biomarker-positive patients were eligible for the study. Only one patient was PIK3CA mutant in a 3' untranslated region (UTR) portion of the gene. This patient was enrolled in the study and failed to meet the 6-month survival endpoint. As the frequency of biomarker-positive patients was very low (<3%), the study was closed. Although we were unable to conclude whether enriching for a subset of second/third line pancreatic cancer patients treated with a Src inhibitor based on a biomarker would improve 6-month survival, we demonstrate that testing pancreatic tumor samples for a biomarker-driven, multicenter study in metastatic pancreas cancer is feasible.


Assuntos
Antineoplásicos/administração & dosagem , Benzodioxóis/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Quinazolinas/administração & dosagem , Quinases da Família src/antagonistas & inibidores , Regiões 3' não Traduzidas/genética , Administração Oral , Adulto , Idoso , Antineoplásicos/efeitos adversos , Benzodioxóis/efeitos adversos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Classe I de Fosfatidilinositol 3-Quinases , Feminino , Humanos , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 2 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Pancreáticas/mortalidade , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Quinazolinas/efeitos adversos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
20.
Mol Oncol ; 6(3): 370-81, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22521243

RESUMO

The Notch signaling pathway has been shown to be upregulated in colorectal cancer (CRC) and important for the self-renewal of cancer stem cells. In this study, we evaluated the efficacy of PF-03084014, a γ-secretase inhibitor, in combination with irinotecan to identify the effects of treatment on tumor recurrence and the tumor-initiating population in our CRC preclinical explant model. The combination of PF-03084014 and irinotecan had the greatest effect at reducing tumor growth on four CRC tumors when compared with treatment with PF-03084014 or irinotecan alone. The combination significantly reduced tumor recurrence in two CRC explants (CRC001 and CRC036) after treatment was discontinued. Both of these tumors exhibited elevated baseline levels of Notch pathway activation as well as an increase in NOTCH1 gene copy number when compared with the two CRC explants (CRC026 and CRC027) where tumors reappeared quickly after termination of treatment. Isolation and injection of aldehyde dehydrogenase (ALDH(+) and ALDH(-)) cells in an in vivo explant model demonstrated that the ALDH(+) cell population were tumorigenic. Evaluation of the ALDH(+) cells after 28 days of treatment showed that the combination reduced the ALDH(+) population in the tumors that did not regrow. Furthermore, ALDH(+) cells from CRC001 and CRC027 were injected in vivo and treated immediately for 28 days. Two months after treatment, tumors were evident in the combination treatment group for CRC027 but not for CRC036. These results indicate the combination of PF-03084014 and irinotecan may be effective in reducing tumor recurrence in CRC patients whose tumors exhibit elevated levels of the Notch pathway.


Assuntos
Aldeído Desidrogenase/metabolismo , Camptotecina/análogos & derivados , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Receptor Notch1/metabolismo , Aldeído Desidrogenase/genética , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Animais , Camptotecina/farmacologia , Camptotecina/uso terapêutico , Neoplasias Colorretais/genética , Feminino , Dosagem de Genes/genética , Humanos , Hibridização in Situ Fluorescente , Irinotecano , Camundongos , Camundongos Nus , Receptor Notch1/genética , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
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