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Denholm J, Schreiber BA, Jaeckle F, Wicks MN, Benbow EW, Bracey TS, Chan JYH, Farkas L, Fryer E, Gopalakrishnan K, Hughes CA, Kirkwood KJ, Langman G, Mahler-Araujo B, McMahon RFT, Myint KLW, Natu S, Robinson A, Sanduka A, Sheppard KA, Tsang YW, Arends MJ, Soilleux EJ. CD, or not CD, that is the question: a digital interobserver agreement study in coeliac disease. BMJ Open Gastroenterol 2024; 11:e001252. [PMID: 38302475 PMCID: PMC10870791 DOI: 10.1136/bmjgast-2023-001252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 12/11/2023] [Indexed: 02/03/2024] Open
Abstract
OBJECTIVE Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis. DESIGN We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data. RESULTS We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09). CONCLUSION We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.
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Affiliation(s)
- James Denholm
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
| | - Benjamin A Schreiber
- Department of Pathology, University of Cambridge, Cambridge, UK
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK
| | - Florian Jaeckle
- Department of Pathology, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
| | - Mike N Wicks
- Department of Pathology, The University of Edinburgh College of Medicine and Veterinary Medicine, Edinburgh, UK
| | - Emyr W Benbow
- Division of Medical Education, The University of Manchester, Manchester, UK
- Department of Histopathology, Manchester University NHS Foundation Trust, Manchester, UK
| | - Tim S Bracey
- Department of Diagnostic and Molecular Pathology, Royal Cornwall Hospitals NHS Trust, Truro, UK
- University Hospitals Plymouth NHS Trust, Plymouth, UK
| | - James Y H Chan
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Lorant Farkas
- Department of Pathology, Akershus University Hospital, Nordbyhagen, Norway
- Institute of Clinical Medicine, University of Oslo, Nordbyhagen, Norway
| | - Eve Fryer
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | - Kishore Gopalakrishnan
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Caroline A Hughes
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | | | - Gerald Langman
- Department of Cellular Pathology, Heartlands Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Betania Mahler-Araujo
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
- MRC Institute of Metabolic Science, Wellcome Trust, Cambridge, UK
| | - Raymond F T McMahon
- Division of Medical Education, The University of Manchester, Manchester, UK
- Department of Histopathology, Manchester University NHS Foundation Trust, Manchester, UK
| | - Khun La Win Myint
- Department of Pathology, Queen Elizabeth University Hospital, Glasgow, UK
| | - Sonali Natu
- University Hospital of North Tees, North Tees and Hartlepool NHS Foundation Trust, Stockton on Tees, UK
| | - Andrew Robinson
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Ashraf Sanduka
- Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - Katharine A Sheppard
- Department of Cellular Pathology, Oxford University Hospitals NHS foundation Trust, Oxford, UK
| | - Yee Wah Tsang
- Department of Histopathology, University Hospitals Coventry and Warwickshire NHS Trust, Coventry, UK
| | - Mark J Arends
- Division of Pathology, University of Edinburgh, Edinburgh, UK
| | - Elizabeth J Soilleux
- Department of Pathology, University of Cambridge, Cambridge, UK
- Lyzeum Ltd, Cambridge, UK
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Campbell E, McLaren O, Sheldon A, Rock B, Bracey TS, Malik T, Reddy VM. A two-centre experience of tonsil biopsies in the investigation of patients with tonsillar asymmetry. Ann R Coll Surg Engl 2024; 106:41-44. [PMID: 36688848 PMCID: PMC10757879 DOI: 10.1308/rcsann.2022.0122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2022] [Indexed: 01/24/2023] Open
Abstract
INTRODUCTION We aim to evaluate our experience of tonsil biopsies in the investigation of patients presenting with asymmetrical tonsils. METHODS A two-centre retrospective analysis of all patients who underwent histology sampling of the palatine tonsils between 1 January 2013 and 31 December 2018 was completed. Data collected included patient demographics, method of obtaining tonsil tissue, histological diagnosis and need for repeat tissue sampling. A follow-up period of 36 months was allowed to establish whether any patients re-presented with missed diagnoses. RESULTS In total, 937 patients were included for analysis: 375 (40.0%) had a biopsy, of which 191 (50.9%) were performed in clinic. The mean duration from initial appointment with the ear, nose and throat clinic to tissue sample collection was 17.6 days (range 0-327 days) for all biopsies, reducing to 0.2 days (range 0-17 days) for biopsies performed in clinic. This was significantly shorter than for tonsillectomies (mean 38.9 days, range 0-444 days; p<0.05). Of the patients who underwent tonsil biopsy, six (1.6%) had malignancy that was not unequivocally diagnosed on initial biopsy. In all six patients, prior clinical suspicion was high, and repeat tissue sampling was undertaken on receipt of negative histology results. CONCLUSIONS Tonsil biopsy is a viable alternative to tonsillectomy for histology in the assessment of tonsil asymmetry. Tonsil biopsy in the outpatient setting has reduced surgical morbidity, significantly less delay in diagnosis, less inconvenience for patients and lower healthcare costs compared with formal tonsillectomy. Although tonsil biopsies should not be used in isolation, they can be useful in the investigation of patients presenting with tonsillar asymmetry.
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Affiliation(s)
| | - O McLaren
- University Hospitals Plymouth NHS Trust, UK
| | - A Sheldon
- University Hospitals Plymouth NHS Trust, UK
| | - B Rock
- Royal Cornwall Hospital NHS Trust, UK
| | - TS Bracey
- Royal Cornwall Hospital NHS Trust, UK
- University Hospitals Plymouth NHS Trust, UK
| | - T Malik
- University Hospitals Plymouth NHS Trust, UK
| | - VM Reddy
- Royal Cornwall Hospital NHS Trust, UK
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Wong NACS, Bracey TS, Mozayani B, Bateman AC, Novelli MR, Shepherd NA. Current dilemmas in the pathological staging of colorectal cancer: the results of a national survey. Histopathology 2020; 78:634-639. [PMID: 33001486 DOI: 10.1111/his.14266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 09/25/2020] [Indexed: 11/27/2022]
Abstract
AIMS Accurate and consistent pathological staging of colorectal carcinoma (CRC) in resection specimens is especially crucial to guide adjuvant therapy. The aim of this study was to assess whether certain staging scenarios yield discordant opinions in the setting of current international and UK national guidelines. METHODS AND RESULTS Members of the UK Gastrointestinal Pathology External Quality Assurance Scheme were invited to complete an anonymous, on-line survey that presented 15 scenarios related to pT or pR staging of CRC, and three questions about the respondent. The survey invitation was e-mailed to 405 pathologists, and 184 (45%) responses were received. The respondents had discordant opinions on whether and how CRC pT or pR staging is affected by: acellular mucin lakes and duration after short-course radiotherapy; the nature of the carcinoma at a resection margin or peritoneal surface; and microscopic evidence of perforation. This discordance was rarely related to the respondent's occupation type, and was not related to duration of work as a consultant or the staging guidelines used. CONCLUSIONS This survey confirms that there remain several clinically critical but unresolved pT and pR staging issues for CRC. These issues therefore deserve attention in future versions of international and national staging guidelines.
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Affiliation(s)
| | - Tim S Bracey
- Department of Diagnostic and Molecular Pathology, Royal Cornwall Hospital, Truro, UK
| | - Behrang Mozayani
- Department of Cellular Pathology, Southmead Hospital, Bristol, UK
| | - Adrian C Bateman
- Department of Cellular Pathology, Southampton General Hospital, Southampton, UK
| | - Marco R Novelli
- Department of Cellular Pathology, University College Hospital, London, UK
| | - Neil A Shepherd
- Gloucestershire Cellular Pathology Laboratory, Cheltenham General Hospital, Cheltenham, UK
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Monteiro de Barros J, Stell D, Bracey TS, Mavroeidis VK. Diffuse liver hamartomatosis (diffuse von Meyenburg complexes) mimicking hepatic metastases on a background of previous cancer. Ann R Coll Surg Engl 2020; 102:e1-e4. [PMID: 32734771 DOI: 10.1308/rcsann.2020.0141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Bile duct hamartomas are typically small benign liver lesions that can radiologically mimic metastases on ultrasound and computed tomography, as well as macroscopically. We present a rare and interesting case and review the relevant literature. A 49-year-old woman underwent ultrasound investigation for right upper quadrant pain, which revealed diffuse liver lesions. In the setting of her previous vulval cancer, it was suspected that she had hepatic metastases. This was strongly reinforced with computed tomography and elevated CA 19-9 levels. A liver biopsy revealed diffuse and multifocal bile duct hamartomas and positron emission tomography was negative for metastases or features of cancer recurrence. A diagnosis of diffuse liver hamartomatosis was made. In view of the continuing clinical and laboratory picture, she required regular follow-up. The collective features of this case are unique, as the isolated characteristics of particular interest have not been previously described in the context of a single case. Bile duct hamartomas should be included in the differential diagnosis of multiple liver lesions. CA 19-9 is not a reliable marker for differential diagnosis of this entity.
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Affiliation(s)
- J Monteiro de Barros
- Peninsula Hepatobiliary and Pancreatic Surgery Unit, Derriford Hospital, Plymouth, UK
| | - D Stell
- Peninsula Hepatobiliary and Pancreatic Surgery Unit, Derriford Hospital, Plymouth, UK
| | - T S Bracey
- Department of Cellular Pathology, Derriford Hospital, Plymouth, UK
| | - V K Mavroeidis
- Peninsula Hepatobiliary and Pancreatic Surgery Unit, Derriford Hospital, Plymouth, UK
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Bracey TS, Keers LC, Adams SA, Smith MEF. Diffuse Gastric Carcinoma Undergoes Characteristic Phenotypic Changes in the Intravascular Environment: Evidence for a Reversal of the Epithelial-Mesenchymal Transition in Lymphovascular Metastasis. Int J Surg Pathol 2016; 25:222-229. [PMID: 27733664 DOI: 10.1177/1066896916672331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This article reports differences between the properties of extravascular carcinoma, which generally forms the vast bulk of a tumor, and those of intravascular carcinoma, at both primary and metastatic lymph node sites. In a morphological and immunohistochemical study of 19 diffuse gastric adenocarcinomas, we report that in comparison to extravascular carcinoma, the intravascular tumor compartment showed frequent and profound phenotypic change, including increased tumor cell cohesion, differentiation and cadherin/catenin expression. For example, greatest cohesion was seen at the intravascular site in 78% ( P = .00006) of primary cancers and in 84% ( P = .000015) of their lymph node metastases. Pan cadherin showed a statistically significant increase at the intravascular metastatic site ( P = .031). We suggest that this change from an extravascular isolated cell phenotype to an intravascular cohesive phenotype represents reversal of the epithelial to mesenchymal transition. Since this proposed reversal of epithelial to mesenchymal transition in intravascular carcinoma is frequently conspicuous in routine histological sections of many types of cancer, as our previous publications have indicated, this process is likely to have widespread significance for the biology of metastasis.
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Bracey TS, Langrish C, Darby M, Soar J. Cerebral infarction following thrombolysis for massive pulmonary embolism. Resuscitation 2006; 68:135-7. [PMID: 16219407 DOI: 10.1016/j.resuscitation.2005.05.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2005] [Revised: 05/23/2005] [Accepted: 05/25/2005] [Indexed: 11/28/2022]
Abstract
A 29-year-old male developed a fatal stroke 6 h after successful thrombolysis for massive pulmonary embolism. Autopsy showed thrombus protruding through a patent foramen ovale (PFO). A strand of thrombus extended from the aortic arch into the left common carotid artery. The brain showed extensive infarction of the left fronto-parietal area. Thrombolysis caused initial disintegration of the embolism. It is likely that thrombolysis caused fragments of clot to later break lose and embolise into the cerebral circulation. We discuss the need for risk stratification in patients who present with massive pulmonary embolism and PFO.
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Affiliation(s)
- Tim S Bracey
- Anaesthetics Department, Southmead Hospital, North Bristol NHS Trust, Bristol BS10 5NB, UK
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Hague A, Bracey TS, Hicks DJ, Reed JC, Paraskeva C. Decreased levels of p26-Bcl-2, but not p30 phosphorylated Bcl-2, precede TGFbeta1-induced apoptosis in colorectal adenoma cells. Carcinogenesis 1998; 19:1691-5. [PMID: 9771943 DOI: 10.1093/carcin/19.9.1691] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Bcl-2 expression is confined to the base of the colonic crypt, whereas transforming growth factor beta (TGFbeta) is expressed in the upper crypt, as are the apoptotic death promoters, Bak and Bax. In colonic adenoma cells, TGFbeta induces a growth arrest. In some adenoma cell lines, this is accompanied by apoptosis and in others it is not. In this study, we used two human colonic adenoma cell lines: RG/C2, in which TGFbeta induces a G1 arrest without apoptosis, and BH/C1, in which TGFbeta induces both a G1 arrest and apoptosis. TGFbeta does not induce apoptosis in RG/C2 cells even if hydrocortisone and insulin are removed from the culture medium. In BH/C1 cells, TGFbeta induces apoptosis in the presence of insulin and hydrocortisone. Apoptosis induced by TGFbeta is preceded by a reduction in p26-Bcl-2 protein levels. There was no change in the levels of the p30 phosphorylated form of Bcl-2 or in levels of the proapoptotic proteins Bax or Bak. RG/C2 cells did not show decreased Bcl-2 levels in response to TGFbeta-induced growth inhibition. Therefore, TGFbeta regulates Bcl-2 expression in colonic adenoma cells which undergo apoptosis in response to TGFbeta, but not in those which are growth inhibited, but resistant to TGFbeta-induced apoptosis. TGFbeta may play an important role in the colonic epithelium, not only in the inhibition of cell proliferation, but also in the regulation of apoptosis.
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Affiliation(s)
- A Hague
- Department of Pathology and Microbiology, University of Bristol, School of Medical Sciences, University Walk, UK.
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Bracey TS, Williams AC, Paraskeva C. Inhibition of radiation-induced G2 delay potentiates cell death by apoptosis and/or the induction of giant cells in colorectal tumor cells with disrupted p53 function. Clin Cancer Res 1997; 3:1371-81. [PMID: 9815821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We have previously identified a p53-independent apoptotic response that is delayed until 48-72 h after irradiation of colorectal adenoma and carcinoma cells. Because the delay appears to be in part due to a transient G2 cell cycle arrest, the importance of this checkpoint in the mechanism of ionizing radiation (IR)-induced death of colorectal tumor cells was investigated. An adenoma cell line with (282Arg-->Trp) mutant p53 (S/RG/C2) and a carcinoma cell line (PC/JW/FI) lacking p53 protein treated with 5 Gy IR in the presence of 1.5 mm caffeine (CAF) reduced IR-induced G2 arrest and increased the level of apoptosis (1.5-1.6-fold) 24 h after treatment. Increased IR apoptotic cell death with CAF significantly reduced IR cell survival over a 7-day period in S/RG/C2 and PC/JW/FI. To investigate whether CAF radiosensitization correlated with lack of wild-type (wt) p53, we studied transfected derivatives of an adenoma-derived cell line (PC/AA/C1), in which the endogenous wt p53 activity was disrupted by the expression of a dominant negative (273Arg-->His) p53 mutant protein (designated AA/273p53/B). This p53-defective cell line was also radiosensitized by CAF, whereas the vector control (AA/PCMV/D), which retained wt p53 activity, was not. In addition, as with the S/RG/C2 and PC/JW/FI cell lines, the 7-day IR cell survival was reduced significantly in AA/273p53/B compared with the vector control cell line. This suggests that radiosensitization by CAF and increased cell death is dependent on loss of wt p53 function. Interestingly, radiosensitization of the AA/273p53/B cell line was not associated with accelerated apoptosis but correlated with increased polyploid giant cells, which have been associated with disruption of cell cycle checkpoints and genomic instability. These results demonstrate that G2 checkpoint inhibition with CAF leads to preferential IR cell killing in cell lines in which wt p53 is inactivated and that this increased cell killing is not necessarily dependent on increased IR-induced apoptosis.
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Affiliation(s)
- T S Bracey
- Cancer Research Campaign Colorectal Tumor Biology Research Group, Department of Pathology, School of Medical Sciences, University of Bristol, University Walk, Bristol BS8 1TD, United Kingdom
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Hague A, Hicks DJ, Bracey TS, Paraskeva C. Cell-cell contact and specific cytokines inhibit apoptosis of colonic epithelial cells: growth factors protect against c-myc-independent apoptosis. Br J Cancer 1997; 75:960-8. [PMID: 9083330 PMCID: PMC2222748 DOI: 10.1038/bjc.1997.167] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
In this study we sought factors that determine the survival of human colonic epithelial cells. Normal colonic epithelial cells are dependent on cell-cell contacts and survival factors for the inhibition of apoptosis whereas, during colorectal tumorigenesis, cells develop mechanisms to evade these controls. The ability to survive loss of cell-cell contacts and/or growth factor deprivation is a marker of tumour progression. Many adenoma (premaligant) cultures survive only if cell-cell contacts are maintained in vitro and die by apoptosis if trypsinized to single cells. This also occurs in adenomas derived from familial adenomatous polyposis (FAP) patients, therefore APC mutations do not confer resistance to cell death in response to loss of cell-cell contacts. We show here that if cell-cell contacts are maintained such cells are capable of survival in suspension. Adenoma cells also undergo apoptosis in response to removal of serum and growth factors from the medium. After removal of serum and growth factors c-myc is down-regulated within 2 h. Therefore, the induction of apoptosis is not an inappropriate response of the cells due to a deregulated c-myc gene. The apoptotic response is also p53 independent. Such cultures have been used to determine specific survival factors for colonic epithelial cells. Insulin, the insulin-like growth factors I and II, hydrocortisone and epidermal growth factor (EGF) protect cells from the induction of apoptosis in the absence of serum over a short-term period of 24 h. This approach may give insight into the factors governing growth and survival of colonic epithelial cells in vivo. This is the first report of specific growth factors protecting against apoptosis in human colonic epithelial cells.
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Affiliation(s)
- A Hague
- CRC Colorectal Tumour Biology Research Group, Department of Pathology and Microbiology, School of Medical Sciences, Bristol, UK
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Williams AC, Miller JC, Collard TJ, Bracey TS, Cosulich S, Paraskeva C. Mutant p53 is not fully dominant over endogenous wild type p53 in a colorectal adenoma cell line as demonstrated by induction of MDM2 protein and retention of a p53 dependent G1 arrest after gamma irradiation. Oncogene 1995; 11:141-9. [PMID: 7624121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
To determine whether a single mutational event in one p53 gene is sufficient to confer a significant growth advantage on a colonic epithelial cell, the 143(Ala) p53 mutation was previously expressed in the human colonic adenoma derived cell line AA/C1 (which is wild type for p53) and shown to have no effect on it's in vitro or in vivo growth characteristics. In this investigation, by expressing the 175(His), 248(Trp) or 273(His) mutations in the same AA/C1 cell line, we have shown that this failure to affect the growth of the cells was not mutant specific. We have also demonstrated, using induction of MDM2 protein and the ability of the cells to undergo a p53 dependent G1 arrest, that the 143(Ala), 175(His) or 248(Trp) transfected cells retain functional endogenous wild type p53 activity, and suggest that these p53 mutations would not have a fully dominant negative mode of action in vivo. In contrast, one of the two AA/C1 cell lines transfected with the 273(His) mutation did fail to cell cycle arrest after gamma irradiation, indicating that this mutation can act as a dominant negative. However even loss of wild type p53 function in this cell line was insufficient to directly effect the growth rate of the AA/C1 cells, suggesting that acquisition of the 273(His) mutation may contribute to malignant progression through genomic instability (by inhibiting the G1 arrest) and that other mutations are required before outgrowth of the cell population containing the p53 mutation.
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Affiliation(s)
- A C Williams
- Department of Pathology and Microbiology, University of Bristol, UK
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Bracey TS, Miller JC, Preece A, Paraskeva C. Gamma-radiation-induced apoptosis in human colorectal adenoma and carcinoma cell lines can occur in the absence of wild type p53. Oncogene 1995; 10:2391-6. [PMID: 7784088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The tumour suppressor gene p53 codes for a transcription factor which is thought to play a critical role in the induction of G1 cell cycle arrest and programmed cell death (apoptosis) following DNA damage by ionizing radiation. The aim of this investigation was to determine whether a p53 independent radiation-induced apoptosis pathway exists in human colon epithelial cell lines. This report describes the induction, by gamma-radiation, of apoptosis in the colorectal adenoma cell line S/RG/C2, and in the colorectal carcinoma cell line PC/JW, both of which lack wild type p53. In addition, flow cytometry revealed that both cell lines failed to arrest in G1 after radiation. Thus, although loss of wild type p53 may abrogate G1 arrest, radiation-induced apoptosis can still occur in human colonic tumour cell lines through a p53 independent mechanism.
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Affiliation(s)
- T S Bracey
- Dept. of Pathology and Microbiology, School of Medical Sciences, University of Bristol, UK
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