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1.
World J Gastrointest Surg ; 16(4): 1030-1042, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690053

RESUMO

Blastomas, characterized by a mixture of mesenchymal, epithelial, and undifferentiated blastematous components, are rare malignant neoplasms originating from precursor blast cells. This review focuses on digestive system blastomas in adult patients, including gastroblastoma, hepatoblastoma, and pancreatoblastoma. Gastroblastoma is a biphasic, epitheliomesenchymal tumor, with only sixteen cases reported to date. In addition to the characteristic histology, metastasis-associated lung adenocarcinoma transcript 1 - glioma-associated oncogene homolog 1 gene fusion is typical, although recently novel ewing sarcoma breakpoint region 1 - c-terminal binding protein 1 and patched 1 - glioma-associated oncogene homolog 2 fusions have been described. Hepatoblastoma is exceptionally rare in adults and can show a variety of histologic patterns which may cause diagnostic difficulty. Pancreatoblastoma, primarily a pediatric tumor, displays acinar differentiation and squamoid nests with other lines of differentiation also present, especially neuroendocrine. Diagnostic approaches for these blastomas include a combination of imaging modalities, histopathological examination, and molecular profiling. The treatment generally involves surgical resection, which may be supplemented by chemotherapy or radiotherapy in some cases. Prognoses vary with gastroblastoma generally showing favorable outcomes post-surgery whereas hepatoblastoma and pancreatoblastoma often have poorer outcomes, particularly in the setting of metastases. This review highlights the complexity of diagnosing and managing these rare adult blastomas as well as the need for ongoing research to better understand their pathogenesis and improve treatment strategies.

2.
Mol Cancer Res ; 19(11): 1929-1945, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34446542

RESUMO

Resistance to cyclin D-CDK4/6 inhibitors (CDK4/6i) represents an unmet clinical need and is frequently caused by compensatory CDK2 activity. Here we describe a novel strategy to prevent CDK4i resistance by using a therapeutic liposomal:peptide formulation, NP-ALT, to inhibit the tyrosine phosphorylation of p27Kip1(CDKN1B), which in turn inhibits both CDK4/6 and CDK2. We find that NP-ALT blocks proliferation in HR+ breast cancer cells, as well as CDK4i-resistant cell types, including triple negative breast cancer (TNBC). The peptide ALT is not as stable in primary mammary epithelium, suggesting that NP-ALT has little effect in nontumor tissues. In HR+ breast cancer cells specifically, NP-ALT treatment induces ROS and RIPK1-dependent necroptosis. Estrogen signaling and ERα appear required. Significantly, NP-ALT induces necroptosis in MCF7 ESRY537S cells, which contain an ER gain of function mutation frequently detected in metastatic patients, which renders them resistant to endocrine therapy. Here we show that NP-ALT causes necroptosis and tumor regression in treatment naïve, palbociclib-resistant, and endocrine-resistant BC cells and xenograft models, demonstrating that p27 is a viable therapeutic target to combat drug resistance. IMPLICATIONS: This study reveals that blocking p27 tyrosine phosphorylation inhibits CDK4 and CDK2 activity and induces ROS-dependent necroptosis, suggesting a novel therapeutic option for endocrine and CDK4 inhibitor-resistant HR+ tumors.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidor de Quinase Dependente de Ciclina p27/efeitos dos fármacos , Necroptose/genética , Inibidores de Proteínas Quinases/uso terapêutico , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Modelos Animais de Doenças , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Estresse Oxidativo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia
3.
Cancer Med ; 10(8): 2723-2731, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33763983

RESUMO

BACKGROUND: Thyroid nodules have a low prevalence of malignancy and most proven cancers do not behave aggressively. Thus, risk-stratification of nodules is a critical step to avoid surgical overtreatment. We hypothesized that a risk management system superior to those currently in use could be created to reduce the number of clinically indeterminate nodules (i.e., the "gray zone") by concurrently considering the malignancy risks conferred by clinical, ultrasonographic, and cytologic variables. METHODS: Thyroidectomy cases were reviewed from three institutions. Their benign versus malignant outcome was used to evaluate the variables for correlation. A binary logistic regression model was trained and, using indeterminate nodules with Bethesda III and IV results, validated. A scoring nomogram was designed to demonstrate the application of the model in clinical practice. RESULTS: One hundred thirty thyroidectomies (28% malignant) met inclusion criteria. The final logistic regression model included difficulty in swallowing, hypothyroidism, echogenicity, hypervascularity, margins, calcification, and cytology diagnosis as input parameters. The model was highly successful in determining the outcome (p value: 0.001) with a R2 (Nagelkerke) score of 0.93. The area under the curve as determined by receiver operating characteristics was 0.91. The accuracy of the model on the training dataset was 93% (sensitivity and specificity 92% and 96%, respectively) and, on the validation dataset, 80% (sensitivity and specificity 91% and 67%, respectively). CONCLUSIONS: We report a model for risk assessment of thyroid nodules that has the potential to significantly reduce indeterminates and surgical overtreatment. We illustrate its application via a straightforward nomogram, which integrates clinical, ultrasonographic, and cytologic data, and can be used to create clear, evidence-based management plans for patients.


Assuntos
Nomogramas , Medição de Risco/métodos , Neoplasias da Glândula Tireoide/patologia , Nódulo da Glândula Tireoide/patologia , Tireoidectomia/métodos , Diagnóstico Diferencial , Gerenciamento Clínico , Feminino , Seguimentos , Humanos , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/cirurgia
4.
Mol Cancer Res ; 17(3): 669-675, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30559257

RESUMO

Cdk4-targeting drugs, such as palbociclib, are approved for metastatic ER/PR+, Her2- breast cancer. However, other than loss of retinoblastoma, which is very rare in this subset, there are no biomarkers to predict response. Cyclin D or cdk4 levels are not by themselves indicative, because p27Kip1 is required for cyclin D-cdk4 complex activation. Tyrosine phosphorylation of p27, including modification on residue Y88 (pY88), activates DK4-p27, and the pY88 level correlates with palbociclib responsiveness in cell lines. We developed dual IHC staining for p27 and pY88, and found that benign breast epithelium was negative, while breast cancer biopsies (of varied hormonal status) could be stratified for pY88 status. Lack of pY88 suggested that DK4 was inactive, and that these samples would not have the target required for palbociclib response. Tumor resection material was grown in explant culture, treated with palbociclib, and stained with Ki67 as a marker of response. Explants from the no pY88 group were nonresponsive, while explants from the low or high pY88 group responded to drug. IMPLICATIONS: Use of the pY88 biomarker, as a surrogate for cdk4 activity, may identify patients responsive to cdk4-targeting drugs and expand use of this therapy.Visual Overview: http://mcr.aacrjournals.org/content/molcanres/17/3/669/F1.large.jpg.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Piperazinas/farmacologia , Piridinas/farmacologia , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Feminino , Humanos , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Técnicas de Cultura de Tecidos , Tirosina/metabolismo
5.
Gastrointest Endosc ; 87(6): 1474-1480, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29325707

RESUMO

BACKGROUND AND AIMS: Pancreatic cancer organoids are tumor models of individualized human pancreatic ductal adenocarcinoma (PDA), created from surgical specimens and used for personalized treatment strategies. Unfortunately, most patients with PDA are not operative candidates. Creation of human PDA organoids at the time of initial tumor diagnosis is therefore critical. Our aim was to assess the feasibility of creating human PDA organoids by EUS fine-needle biopsy (EUS-FNB) sampling in patients with PDA. METHODS: In this prospective clinical trial in patients referred to evaluate a pancreatic mass, EUS-FNA was performed for initial onsite diagnosis. Two additional needle passes were performed with a 22-gauge FNB needle for organoid creation. Primary outcome was successful isolation of organoids within 2 weeks of EUS-FNB sampling (P0, no passages), confirmed by organoid morphology and positive genotyping. RESULTS: Thirty-seven patients with 38 PDA tumors were enrolled. Successful isolation of organoids (P0) was achieved in 33 of 38 tumors (87%). Establishment of PDA organoid lines for ≥5 passages of growth (P5, five passages) was reached in 25 of 38 tumors (66%). In the single patient with successful P5 FNB sampling-derived and P5 surgically derived organoids, there was identical matching of specimens. There were no serious adverse events. Two patients developed bleeding at the EUS-FNB puncture site requiring hemostasis clips. CONCLUSIONS: Pancreatic cancer organoids can be successfully and rapidly created by means of EUS-FNB sampling using a 22-gauge needle at the time of initial diagnosis. Successful organoid generation is essential for precision medicine in patients with pancreatic cancer in whom most are not surgically resectable. (Clinical trial registration number: NCT03140592.).


Assuntos
Carcinoma Ductal Pancreático , Organoides , Neoplasias Pancreáticas , Idoso , Idoso de 80 Anos ou mais , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medicina de Precisão , Técnicas de Cultura de Tecidos , Células Tumorais Cultivadas
6.
Mol Cancer Res ; 16(3): 361-377, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29330290

RESUMO

Cyclin-dependent kinase 4/6 (CDK4/6)-specific inhibitors, such as palbociclib, have shown clinical efficacy, but primary or secondary resistance has emerged as a problem. To develop more effective therapeutic approaches, investigation is needed into the mechanisms of resistance or adaption. Here, it is demonstrated that CDK2 compensates for loss of CDK4 activity to rescue palbociclib-arrested breast cancer cells, suggesting that inhibition of both kinases is required to achieve durable response. In addition, a novel strategy is described to inhibit tyrosine phosphorylation of p27Kip1 (CDKN1B) and simultaneously inhibit both CDK2 and CDK4. p27Kip1 is a required assembly factor for cyclin-CDK4 complexes, but it must be phosphorylated on residue Y88 to open or activate the complex. The Brk-SH3 peptide, ALT, blocks p27 Y88 phosphorylation, inhibiting CDK4. Nonphosphorylated p27 is no longer a target for ubiquitin-mediated degradation and this stabilized p27 now also inhibits CDK2 activity. Thus, ALT induction inhibits both the kinase that drives proliferation (CDK4) and the kinase that mediates resistance (CDK2), causing a potent and long-lasting cell-cycle arrest. ALT arrests growth of all breast cancer subgroups and synergizes with palbociclib to increase cellular senescence and to cause tumor regression in breast cancer xenograft models. The use of ALT demonstrates that both CDK4 and CDK2 need to be inhibited if long-term efficacy is to be achieved and represents a novel modality to inhibit breast cancer cells.Implications: Modulating tyrosine phosphorylation of p27 impacts both proliferative (CDK4) and resistance (CDK2) mechanisms in breast cancer and suggests that phospho-p27 status may serve as a biomarker for patients that are responsive to CDK4/6 inhibition. Mol Cancer Res; 16(3); 361-77. ©2018 AACR.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Quinase 2 Dependente de Ciclina/antagonistas & inibidores , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Proteínas de Neoplasias/farmacologia , Fragmentos de Peptídeos/farmacologia , Proteínas Tirosina Quinases/farmacologia , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Quinase 2 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/metabolismo , Feminino , Humanos , Células MCF-7 , Camundongos , Camundongos Endogâmicos NOD , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Fosforilação , Proteínas Tirosina Quinases/química , Proteínas Tirosina Quinases/metabolismo , Transfecção , Domínios de Homologia de src
7.
Cancer Cytopathol ; 125(12): 926-933, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28885766

RESUMO

BACKGROUND: Fine-needle aspiration (FNA) biopsy is an accurate method for the diagnosis of solid pancreatic masses. However, a significant number of cases still pose a diagnostic challenge. The authors have attempted to design a computer model to aid in the diagnosis of these biopsies. METHODS: Images were captured of cell clusters on ThinPrep slides from 75 pancreatic FNA cases (20 malignant, 24 benign, and 31 atypical). A K-means clustering algorithm was used to segment the cell clusters into separable regions of interest before extracting features similar to those used for cytomorphologic assessment. A multilayer perceptron neural network (MNN) was trained and then tested for its ability to distinguish benign from malignant cases. RESULTS: A total of 277 images of cell clusters were obtained. K-means clustering identified 68,301 possible regions of interest overall. Features such as contour, perimeter, and area were found to be significantly different between malignant and benign images (P <.05). The MNN was 100% accurate for benign and malignant categories. The model's predictions from the atypical data set were 77% accurate. CONCLUSIONS: The results of the current study demonstrate that computer models can be used successfully to distinguish benign from malignant pancreatic cytology. The fact that the model can categorize atypical cases into benign or malignant with 77% accuracy highlights the great potential of this technology. Although further study is warranted to validate its clinical applications in pancreatic and perhaps other areas of cytology as well, the potential for improved patient outcomes using MNN for image analysis in pathology is significant. Cancer Cytopathol 2017;125:926-33. © 2017 American Cancer Society.


Assuntos
Carcinoma Ductal Pancreático/patologia , Simulação por Computador , Diagnóstico por Computador/métodos , Redes Neurais de Computação , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Neoplasias dos Ductos Biliares/patologia , Biópsia por Agulha Fina , Carcinoma Ductal Pancreático/mortalidade , Citodiagnóstico/métodos , Diagnóstico Diferencial , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pâncreas/cirurgia , Pancreatectomia , Neoplasias Pancreáticas/cirurgia , Reprodutibilidade dos Testes
8.
Diagn Cytopathol ; 42(2): 111-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23636867

RESUMO

Distinguishing reactive mesothelial cells from metastatic disease, typically adenocarcinoma, in effusion cytology can be challenging at times. We currently use a panel of immunocytochemical markers for select cases including MOC-31 and BerEp4, but difficulties still exist. Enhancer of zeste homologue 2 (EZH2) plays important roles in epigenetic silencing and cell cycle regulation and is upregulated in a wide variety of malignancies. Thus, we hypothesized that EZH2 immunocytochemistry, which to our knowledge has not yet been reported on cytology material, might serve as a unique marker of malignancy in morphologically equivocal effusion specimens by highlighting aberrant protein expression in malignant cells. A total of 96 (48 benign and 48 malignant) effusion cases were selected retrospectively from our department archives. All malignant cases were metastatic adenocarcinomas except for three high grade neuroendocrine carcinomas (two lungs and one ovary), one cervical squamous cell carcinoma, and one epithelioid endometrial stromal sarcoma. The 48 benign cases were all negative for EZH2, and 43 of 48 malignant effusions were positive. As a solitary marker, EZH2 exhibited a sensitivity of 90% and a specificity of 100% (P < 0.0001). EZH2 functioned as a unique and accurate marker of malignancy in this series of effusions. Relative to published data, EZH2 demonstrated a sensitivity comparable to MOC-31 and superior to BerEp4, and a specificity superior to both of these commonly used immunostains. Thus, EZH2 is likely to be of great value as an adjunct to morphology in diagnosing malignancy in effusion specimens.


Assuntos
Adenocarcinoma/química , Biomarcadores Tumorais/análise , Neoplasias Pulmonares/química , Mesotelioma/química , Derrame Pleural Maligno/química , Derrame Pleural Maligno/patologia , Complexo Repressor Polycomb 2/análise , Adenocarcinoma/patologia , Adenocarcinoma/secundário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/patologia , Neoplasias do Sistema Digestório/química , Neoplasias do Sistema Digestório/patologia , Neoplasias do Endométrio/química , Neoplasias do Endométrio/patologia , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Masculino , Mesotelioma/patologia , Pessoa de Meia-Idade , Neoplasias Ovarianas/química , Neoplasias Ovarianas/patologia , Estudos Retrospectivos , Sarcoma/química , Sarcoma/patologia , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/química , Neoplasias do Colo do Útero/patologia , Adulto Jovem
9.
Diagn Cytopathol ; 42(11): 956-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24273019

RESUMO

Primary gynecological lymphomas are rare and difficult to diagnose with Pap test. Herein, we report an uncommon case of plasmablastic lymphoma in a 61-year-old female with human immunodeficiency virus that presents with vaginal bleeding. The following case report shows the cytological features on liquid-based Pap test, cell block studies with diagnostic immunohistochemistry, discussion of the diagnostic difficulties, and a literature review.


Assuntos
Linfoma/diagnóstico por imagem , Neoplasias Pélvicas/diagnóstico por imagem , Feminino , Infecções por HIV/imunologia , Humanos , Pessoa de Meia-Idade , Teste de Papanicolaou , Radiografia , Esfregaço Vaginal
10.
Gynecol Oncol Case Rep ; 2(4): 136-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24371646

RESUMO

► We present the case with the latest reported recurrence of low malignant potential ovarian tumor. ► Borderline ovarian tumors have the potential for delayed recurrence that is not always salvageable surgically. ► Optimization of surveillance strategies and lifelong follow up is required for these patients.

11.
Acta Cytol ; 54(2): 123-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20391966

RESUMO

OBJECTIVE: To identifiy categories of potentially neoplastic, nonpapillary follicular lesions of the thyroid that would reduce the number of lobectomies for nonneoplastic disease. STUDY DESIGN: The literature regarding fine needle aspiration (FNA) of follicular lesions is difficult to interpret largely due to the poor standardization of diagnostic categories. Based on our categorization scheme, which is directly comparable to the new system proposed by the National Cancer Institute (NCI), we quantitatively evaluated the cytomorphologic features of 99 "atypical" cases. RESULTS: Histologic evaluation revealed a 63% neoplasia rate and a 26% malignancy rate. Lesions with an abundance of macrophages and colloid on FNA were significantly less likely to be neoplastic or malignant. The strongest predictors of any neoplasia included absence of colloid and increased cellularity, which remained significant even after adjustment for all selected variables. CONCLUSION: Unlike similar studies, ours statistically significant variables that may assist how to manage follicular lesions better. Further, our current diagnostic scheme is equivalent to that recently proposed by the NCI, and, herein, we not only illustrate its application in clinical practice but also highlight potential pitfalls of this system.


Assuntos
Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Adenocarcinoma Folicular/patologia , Adenoma/patologia , Adulto , Biópsia por Agulha Fina , Carcinoma Papilar/patologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias da Glândula Tireoide/classificação
12.
Am J Clin Pathol ; 126(1): 120-7, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16753592

RESUMO

To evaluate the utilization of thrombophilia screening at a large urban academic tertiary care center, we retrospectively examined the indications, appropriateness, and results of 200 consecutive thrombophilia panels. Of the panels, 103 (51.5%) were ordered for venous thromboembolism; 124 (62.0%) were ordered during acute thrombotic episodes, and at least 40 (20.0%) had abnormal protein C and S results, of which 25 (63%) were attributable to anticoagulation and the remainder to pregnancy. Of the 200 panels, 46 (23.0%) had a significant abnormality; the most common abnormal result was a lupus anticoagulant, occurring in 23 cases (11.3%). Thrombophilia screening seems to be overutilized in our population, especially considering that the majority of tests are ordered during suboptimal conditions, eg, acute thrombosis, pregnancy, or anticoagulation. At present, outside the research setting, thrombophilia panels should be reserved for special circumstances, targeted to factors for which there would be a specific clinical impact, and performed in the absence of confounding clinical variables.


Assuntos
Testes de Coagulação Sanguínea/estatística & dados numéricos , Hospitais Urbanos/estatística & dados numéricos , Programas de Rastreamento/métodos , Trombofilia/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cidade de Nova Iorque/epidemiologia , Prevalência , Estudos Retrospectivos , Tromboembolia/diagnóstico , Tromboembolia/etiologia , Trombofilia/complicações , Trombofilia/epidemiologia , Trombose Venosa/diagnóstico , Trombose Venosa/etiologia
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