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1.
J Pathol ; 251(3): 310-322, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32315081

RESUMO

The phenotypic spectrum of colorectal cancer (CRC) is remarkably diverse, with seemingly endless variations in cell shape, mitotic figures and multicellular configurations. Despite this morphological complexity, histological grading of collective phenotype patterns provides robust prognostic stratification in CRC. Although mechanistic understanding is incomplete, previous studies have shown that the cortical protein ezrin controls diversification of cell shape, mitotic figure geometry and multicellular architecture, in 3D organotypic CRC cultures. Because ezrin is a substrate of Src tyrosine kinase that is frequently overexpressed in CRC, we investigated Src regulation of ezrin and morphogenic growth in 3D CRC cultures. Here we show that Src perturbations disrupt CRC epithelial spatial organisation. Aberrant Src activity suppresses formation of the cortical ezrin cap that anchors interphase centrosomes. In CRC cells with a normal centrosome number, these events lead to mitotic spindle misorientation, perturbation of cell cleavage, abnormal epithelial stratification, apical membrane misalignment, multilumen formation and evolution of cribriform multicellular morphology, a feature of low-grade cancer. In isogenic CRC cells with centrosome amplification, aberrant Src signalling promotes multipolar mitotic spindle formation, pleomorphism and morphological features of high-grade cancer. Translational studies in archival human CRC revealed associations between Src intensity, multipolar mitotic spindle frequency and high-grade cancer morphology. Collectively, our study reveals Src regulation of CRC morphogenic growth via ezrin-centrosome engagement and uncovers combined perturbations underlying transition to high-grade CRC morphology. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Centrossomo/enzimologia , Neoplasias Colorretais/enzimologia , Proteínas do Citoesqueleto/metabolismo , Mitose , Quinases da Família src/metabolismo , Células CACO-2 , Centrossomo/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/genética , Quinase 1 de Adesão Focal/genética , Quinase 1 de Adesão Focal/metabolismo , Células HCT116 , Humanos , Gradação de Tumores , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Transdução de Sinais , Quinases da Família src/genética
2.
Am J Pathol ; 188(9): 1936-1948, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30028958

RESUMO

Colorectal cancer (CRC) diagnosis and prognostic stratification are based on histopathologic assessment of cell or nuclear pleomorphism, aberrant mitotic figures, altered glandular architecture, and other phenomic abnormalities. This complexity is driven by oncogenic perturbation of tightly coordinated spatiotemporal signaling to disrupt multiple scales of tissue organization. This review clarifies molecular and cellular mechanisms underlying common CRC histologic features and helps understand how the CRC genome controls core aspects of tumor aggressiveness. It further explores a spatiotemporal framework for CRC phenomics based on regulation of living cells in fundamental and organotypic model systems. The review also discusses tissue homeostasis, considers distinct classes of oncogenic perturbations, and evolution of cellular or multicellular cancer phenotypes. It further explores the molecular controls of cribriform, micropapillary, and high-grade CRC morphology in organotypic culture models and assesses relevant translational studies. In addition, the review delves into complexities of morphologic plasticity whereby a single molecular signature generates heterogeneous cancer phenotypes, and, conversely, morphologically homogeneous tumors show substantive molecular diversity. Principles outlined may aid mechanistic interpretation of omics data in a setting of cancer pathology, provide insight into CRC consensus molecular subtypes, and better define principles for CRC prognostic stratification.


Assuntos
Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Técnicas de Cultura de Órgãos/métodos , Animais , Humanos
3.
J Pathol ; 244(4): 445-459, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29520890

RESUMO

Histological grading provides prognostic stratification of colorectal cancer (CRC) by scoring heterogeneous phenotypes. Features of aggressiveness include aberrant mitotic spindle configurations, chromosomal breakage, and bizarre multicellular morphology, but pathobiology is poorly understood. Protein kinase C zeta (PKCz) controls mitotic spindle dynamics, chromosome segregation, and multicellular patterns, but its role in CRC phenotype evolution remains unclear. Here, we show that PKCz couples genome segregation to multicellular morphology through control of interphase centrosome anchoring. PKCz regulates interdependent processes that control centrosome positioning. Among these, interaction between the cytoskeletal linker protein ezrin and its binding partner NHERF1 promotes the formation of a localized cue for anchoring interphase centrosomes to the cell cortex. Perturbation of these phenomena induced different outcomes in cells with single or extra centrosomes. Defective anchoring of a single centrosome promoted bipolar spindle misorientation, multi-lumen formation, and aberrant epithelial stratification. Collectively, these disturbances induce cribriform multicellular morphology that is typical of some categories of low-grade CRC. By contrast, defective anchoring of extra centrosomes promoted multipolar spindle formation, chromosomal instability (CIN), disruption of glandular morphology, and cell outgrowth across the extracellular matrix interface characteristic of aggressive, high-grade CRC. Because PKCz enhances apical NHERF1 intensity in 3D epithelial cultures, we used an immunohistochemical (IHC) assay of apical NHERF1 intensity as an indirect readout of PKCz activity in translational studies. We show that apical NHERF1 IHC intensity is inversely associated with multipolar spindle frequency and high-grade morphology in formalin-fixed human CRC samples. To conclude, defective PKCz control of interphase centrosome anchoring may underlie distinct categories of mitotic slippage that shape the development of low- or high-grade CRC phenotypes. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Assuntos
Centrossomo/enzimologia , Neoplasias Colorretais/enzimologia , Interfase , Proteína Quinase C/metabolismo , Células CACO-2 , Proliferação de Células , Forma Celular , Instabilidade Cromossômica , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Humanos , Gradação de Tumores , Fenótipo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteína Quinase C/genética , Transdução de Sinais , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo
5.
Vasc Med ; 16(6): 415-21, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22128040

RESUMO

The management of small abdominal aortic aneurysms (AAA) is by ultrasound surveillance. The study aimed to calculate their growth rate, identify risk factors and determine appropriate screening intervals. The local screening programme and hospital records were used to identify patients with a small (< 5.5 cm) AAA. The dates and maximum diameter of serial scans of patients with two or more scans were obtained. Patients were subdivided by 0.5 cm increments above 3.0 cm. The rate of growth was calculated by linear regression for each patient using both the absolute measurements and logarithmically (ln) transformed measurements. The 95th centile of growth rate within each subgroup was used to estimate the minimum time to grow to 5.5 cm. A total of 252 were included. The mean (± SD) AAA size on the initial scan was 3.9 (± 0.7) cm. Statin use and initial size were predictive factors for the growth rate. The median rate of growth increased according to size from 0.075 to 0.432 cm/year for AAA < 3.5 cm and > 5.0 cm, respectively. It also steadily increased for ln measurements from 0.022 (or 2.2%/year) to 0.078 or (7.8%/year). The minimum time (months) to reach 5.5 cm was 61, 17, 11 and 5 for AAA < 3.5 cm, 3.5-3.9 cm, 4.0-4.4 cm and 4.5-4.9 cm, respectively. Based on ln measurements, the times were similar at 60, 17, 10 and 4 months. In conclusion, the rate of growth increased steadily with AAA size. An aneurysm < 3.5 cm does not require a repeat scan for 5 years, while those measuring 3.5-3.9 cm and 4.0-4.4 cm require a repeat scan after 17 and 11 months.


Assuntos
Aorta Abdominal/patologia , Aneurisma da Aorta Abdominal/diagnóstico , Conduta Expectante , Idoso , Aneurisma da Aorta Abdominal/diagnóstico por imagem , Agendamento de Consultas , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Masculino , Tamanho do Órgão , Fatores de Tempo , Ultrassonografia
6.
Oncotarget ; 7(31): 49042-49064, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27119498

RESUMO

Development of cribriform morphology (CM) heralds malignant change in human colon but lack of mechanistic understanding hampers preventive therapy. This study investigated CM pathobiology in three-dimensional (3D) Caco-2 culture models of colorectal glandular architecture, assessed translational relevance and tested effects of 1,25(OH)2D3,theactive form of vitamin D. CM evolution was driven by oncogenic perturbation of the apical polarity (AP) complex comprising PTEN, CDC42 and PRKCZ (phosphatase and tensin homolog, cell division cycle 42 and protein kinase C zeta). Suppression of AP genes initiated a spatiotemporal cascade of mitotic spindle misorientation, apical membrane misalignment and aberrant epithelial configuration. Collectively, these events promoted "Swiss cheese-like" cribriform morphology (CM) comprising multiple abnormal "back to back" lumens surrounded by atypical stratified epithelium, in 3D colorectal gland models. Intestinal cancer driven purely by PTEN-deficiency in transgenic mice developed CM and in human CRC, CM associated with PTEN and PRKCZ readouts. Treatment of PTEN-deficient 3D cultures with 1,25(OH)2D3 upregulated PTEN, rapidly activated CDC42 and PRKCZ, corrected mitotic spindle alignment and suppressed CM development. Conversely, mutationally-activated KRAS blocked1,25(OH)2D3 rescue of glandular architecture. We conclude that 1,25(OH)2D3 upregulates AP signalling to reverse CM in a KRAS wild type (wt), clinically predictive CRC model system. Vitamin D could be developed as therapy to suppress inception or progression of a subset of colorectal tumors.


Assuntos
Adenocarcinoma/patologia , Colecalciferol/farmacologia , Colo/patologia , Neoplasias Colorretais/patologia , Adenocarcinoma/tratamento farmacológico , Animais , Células CACO-2 , Técnicas de Cultura de Células , Transformação Celular Neoplásica , Estudos de Coortes , Neoplasias Colorretais/tratamento farmacológico , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Transgênicos , Mitose , Mutação , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Prognóstico , Proteína Quinase C/metabolismo , Receptores de Calcitriol/metabolismo , Transdução de Sinais , Transfecção , Proteína cdc42 de Ligação ao GTP/metabolismo
7.
Ann R Coll Surg Engl ; 92(2): 136-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20353641

RESUMO

INTRODUCTION: The National Health Service (NHS) Cancer Plan guidelines recommend a maximum 2-week wait from referral to first appointment, and 2 months from referral to treatment for primary cancers. However, there are currently no guidelines available for metastatic disease. In the UK, nearly half of all colorectal cancer patients develop hepatic metastases. Timely, surgical resection offers the potential for cure. The aim of this study was to audit current practice for colorectal liver metastases in a regional hepatobiliary unit, and compare this to the NHS Cancer Plan standards for primary disease. PATIENTS AND METHODS: A retrospective review of the unit's database was performed for all hepatic metastases referrals from January 2006 to December 2008. The dates of referral, first appointment, investigations and initiation of treatment, along with patient's age and sex, were recorded on Microsoft Excel and analysed. Time was expressed as mean +/- SD in days. RESULTS: A total of 102 patients with hepatic metastases were identified. Five were excluded due to incomplete data. The average time from referral to first appointment was 10.6 +/- 9.4 days and the average time from referral to treatment was 38.5 +/- 28.6 days. Seventy-five (72.7%) had surgical intervention, of whom 37 also had chemotherapy. CONCLUSIONS: The data compare favourably to the NHS Cancer Plan guidelines for primary malignancy, demonstrating that a regional hepatobiliary unit is capable of delivering a service for colorectal liver metastases that adheres to the NHS Cancer Plan. Therefore, the NHS Cancer Plan can be applied to this cohort.


Assuntos
Neoplasias Colorretais , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/cirurgia , Medicina Estatal/normas , Listas de Espera , Idoso , Feminino , Fidelidade a Diretrizes , Humanos , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Irlanda do Norte , Guias de Prática Clínica como Assunto , Encaminhamento e Consulta/normas , Encaminhamento e Consulta/estatística & dados numéricos , Fatores de Tempo
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