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Yilmaz HE, Yilmaz M, Tangirala VA, Spring K. Awareness of surgical smoke risks and assessment of safety practices during the Covid-19 pandemic. NMJI 2022; 35:189-190. [DOI: 10.25259/nmji-35-3-189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Affiliation(s)
- Huriye Erbak Yilmaz
- Department of Biochemistry, University of Katip Celebi University Ataturk Education and Research Hospital, Turkey
- Izmir Biomedicine and Genome Centre, University of Dokuz Eylul, Turkey
| | - Murat Yilmaz
- Department of Neurosurgery, University of Dokuz Eylul, School of Medicine Izmir, Turkey
| | | | - Kevin Spring
- Department of Medical Oncology, Ingham Institute for Applied Medical Research, School of Medicine, Western Sydney University and SWS Clinical School, UNSW, Sydney, NSW, Australia
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Toh JWT, Mahajan H, Chapuis P, Spring K. Current status on microsatellite instability, prognosis and adjuvant therapy in colon cancer: A nationwide survey of medical oncologists, colorectal surgeons and gastrointestinal pathologists. Cancer Rep (Hoboken) 2020; 4:e1297. [PMID: 33030308 PMCID: PMC7941492 DOI: 10.1002/cnr2.1297] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/29/2020] [Accepted: 09/08/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND There is significant variation in attitude both towards the role of microsatellite instability (MSI) in predicting prognosis, and towards its role in guiding which Stage II colon cancer patients may benefit from adjuvant chemotherapy. AIM To examine the current status of specialist attitudes towards MSI in guiding prognosis and adjuvant therapy in stage II colon cancer. METHODS The Pathology in Colon Cancer, Prognosis and Uptake of Adjuvant Therapy (PiCC UP) Australia and New Zealand questionnaire was distributed to colorectal surgeons, medical oncologists and pathologists after institutional board approval. A 5-scale Likert score was used to assess attitudes towards 23 pathological features for prognosis and 18 features for adjuvant therapy. Data were analysed using a rating scale and graded response model in item response theory (IRT) on STATA (Stata MP, version 15; StataCorp LP). RESULTS 164 specialists (45 oncologists, 86 surgeons and 33 pathologists) participated. 80.5% regularly attended colorectal multidisciplinary team (MDT) meetings. 89.63% and 59.26% of specialists reported that MSI status was likely or definitely to influence prognosis in colon cancer and recommendations for adjuvant therapy in Stage II colon cancer respectively. IRT modelling was achieved in 17 pathological features for prognosis. MSI IRT score was 4.47 (95% CI: 4.05-4.68). IRT modelling was achieved in 10 pathological features for adjuvant therapy. MSI IRT score was 3.62 (2.89-4.15). MSI ranked 10 (of 17) in order of importance in determining prognosis and ranked three (of 10) in guiding adjuvant therapy. CONCLUSION MSI status is considered an important biomarker when selecting patients for adjuvant therapy in Stage II colon cancer. MSI is also considered useful in prognostication of colon cancer. MSI status was ranked similar to the tumour grade of differentiation and the presence of perineural invasion.
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Affiliation(s)
- James W T Toh
- Department of Surgery, Westmead Hospital, Sydney, New South Wales, Australia.,The University of Sydney, Sydney, New South Wales, Australia.,Ingham Institute of Applied Research, Sydney, New South Wales, Australia
| | - Hema Mahajan
- Department of Surgery, Westmead Hospital, Sydney, New South Wales, Australia.,Institute Of Clinical Pathology And Medical Research (ICPMR), Westmead Hospital, Sydney, New South Wales, Australia
| | - Pierre Chapuis
- The University of Sydney, Sydney, New South Wales, Australia
| | - Kevin Spring
- Ingham Institute of Applied Research, Sydney, New South Wales, Australia
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Toh W, Toh J, Ferguson A, Spring K, Mehajan H, Palendira M. Microsatellite instability and immunogenicity in colorectal cancer: Do resident memory Tcells (Trm) play a role in colorectal cancer? Ann Oncol 2019. [DOI: 10.1093/annonc/mdz246.093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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4
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Toh J, Spring K. Microsatellite Instability (MSI) status and prognosis in colorectal cancer: Meta-analysis. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz246.059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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5
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Spring K, Toh J, Chapuis P, Bokey L, Chan C, Dent O. Competing risks analysis of microsatellite instability as a prognostic factor in colorectal cancer. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy151.201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Lorent JH, Diaz-Rohrer B, Lin X, Spring K, Gorfe AA, Levental KR, Levental I. Structural determinants and functional consequences of protein affinity for membrane rafts. Nat Commun 2017; 8:1219. [PMID: 29089556 PMCID: PMC5663905 DOI: 10.1038/s41467-017-01328-3] [Citation(s) in RCA: 177] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 09/09/2017] [Indexed: 12/14/2022] Open
Abstract
Eukaryotic plasma membranes are compartmentalized into functional lateral domains, including lipid-driven membrane rafts. Rafts are involved in most plasma membrane functions by selective recruitment and retention of specific proteins. However, the structural determinants of transmembrane protein partitioning to raft domains are not fully understood. Hypothesizing that protein transmembrane domains (TMDs) determine raft association, here we directly quantify raft affinity for dozens of TMDs. We identify three physical features that independently affect raft partitioning, namely TMD surface area, length, and palmitoylation. We rationalize these findings into a mechanistic, physical model that predicts raft affinity from the protein sequence. Application of these concepts to the human proteome reveals that plasma membrane proteins have higher raft affinity than those of intracellular membranes, consistent with raft-mediated plasma membrane sorting. Overall, our experimental observations and physical model establish general rules for raft partitioning of TMDs and support the central role of rafts in membrane traffic.
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Affiliation(s)
- Joseph H Lorent
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Blanca Diaz-Rohrer
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Xubo Lin
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Kevin Spring
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Alemayehu A Gorfe
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Kandice R Levental
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA
| | - Ilya Levental
- McGovern Medical School, University of Texas Health Science Center, Houston MSB 4.202A, 6431 Fannin St, Houston, TX, 77096, USA.
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Lim SHS, Ip E, Chua W, Ng W, Henderson C, Shin JS, Harris BHL, Barberis A, Cowley M, De Souza PL, Spring K. Serum microRNA expression during neoadjuvant chemoradiation for rectal cancer. J Clin Oncol 2017. [DOI: 10.1200/jco.2017.35.15_suppl.e15081] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
e15081 Background: Changes in microRNA (miRNA) expression during treatment for locally advanced rectal cancer (LARC) may provide insight into disease biology and potentially act as predictive biomarkers. We investigated 112 miRNAs in serum during neoadjuvant chemoradiation for LARC. Methods: Serum was collected at baseline, week 3 and at completion of chemoradiation from 40 prospectively recruited patients with LARC. Responders were classed as tumour regression grade (AJCC classification) 0 or 1 and non-responders as 2 or 3. Serum was also collected from 20 healthy controls. RNA extraction was performed using the Norgen total RNA purification kit. Reverse transcription and pre-amplification were performed according to Taqman OpenArray MicroRNA Panels manufacturer's instructions. QuantStudio12K platform was used for miRNA array qPCR. The delta-delta-Ct method was used to identifiy differentially expressed miRNAs, normalised against U6 snRNA. Analysis was performed in R using paired t-statistics and the Benjamini-Hochberg False Discovery Rate for multiple hypothesis testing adjustment, with q < 0.05 for significance. Enriched KEGG pathways were identified using DIANA, based on verified gene targets of each miRNA from Tarbase. Results: Four miRNAs (miR-125b-1, miR-1183, miR-130a, miR-375) were differentially expressed in baseline patient samples compared to controls. From baseline to completion of treatment, three of these - miR-125b-1, miR-1183, miR-130a were downregulated by more than 2-fold. Comparing responders and non-responders, miR-130a was significantly downregulated in the non-responders only. Conclusions: miR-125b-1, miR-1183 and miR-130a are significantly downregulated in patients with LARC during chemoradiation. These miRNAs are known to target key colorectal cancer genes such as ATM and CHEK1, which have been implicated in chemoradiation resistance. miR-130a warrants further investigation as a predictive biomarker, being downregulated in patients with a poor response to therapy. Work is ongoing, investigating these miRNA targets in the solid tissue in these patients. To our knowledge, this is the first study to profile potentially predictive miRNA changes during chemoradiation in LARC.
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Affiliation(s)
| | - Emilia Ip
- Liverpool Cancer Therapy Centre, Liverpool, Australia
| | - Wei Chua
- Liverpool Cancer Therapy Centre, Liverpool, Australia
| | - Weng Ng
- Liverpool Cancer Therapy Centre, Liverpool, Australia
| | | | - J-S Shin
- Department of Anatomical Pathology, Liverpool Hospital, Liverpool, Australia
| | - Benjamin Howell Lole Harris
- Computational Biology and Integrative Genomics, Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Alessandro Barberis
- Computational Biology and Integrative Genomics, Department of Oncology, University of Oxford, Oxford, United Kingdom
| | - Mark Cowley
- Kinghorn Centre for Clinical Genomics, Garvan Institute, Darlinghurst, Australia
| | - Paul L. De Souza
- University of Western Sydney School of Medicine, Liverpool, Australia
| | - Kevin Spring
- Ingham Institute for Applied Medical Research, Liverpool, Australia
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Randall-Demllo S, Fernando R, Brain T, Sohal SS, Cook AL, Guven N, Kunde D, Spring K, Eri R. Characterisation of colonic dysplasia-like epithelial atypia in murine colitis. World J Gastroenterol 2016; 22:8334-8348. [PMID: 27729740 PMCID: PMC5055864 DOI: 10.3748/wjg.v22.i37.8334] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Revised: 08/15/2016] [Accepted: 09/06/2016] [Indexed: 02/06/2023] Open
Abstract
AIM To determine if exacerbation of pre-existing chronic colitis in Winnie (Muc2 mutant) mice induces colonic dysplasia.
METHODS Winnie mice and C57BL6 as a genotype control, were administered 1% w/v dextran sulphate sodium (DSS) orally, followed by drinking water alone in week-long cycles for a total of three cycles. After the third cycle, mice were killed and colonic tissue collected for histological and immunohistochemical evaluation. Inflammation and severity of dysplasia in the colonic mucosa were assessed in H&E sections of the colon. Epithelial cell proliferation was assessed using Ki67 and aberrant β-catenin signalling assessed with enzyme-based immunohistochemistry. Extracted RNA from colonic segments was used for the analysis of gene expression using real-time quantitative PCR. Finally, the distribution of Cxcl5 was visualised using immunohistochemistry.
RESULTS Compared to controls, Winnie mice exposed to three cycles of DSS displayed inflammation mostly confined to the distal-mid colon with extensive mucosal hyperplasia and regenerative atypia resembling epithelial dysplasia. Dysplasia-like changes were observed in 100% of Winnie mice exposed to DSS, with 55% of these animals displaying changes similar to high-grade dysplasia, whereas high-grade changes were absent in wild-type mice. Occasional penetration of the muscularis mucosae by atypical crypts was observed in 27% of Winnie mice after DSS. Atypical crypts however displayed no evidence of oncogenic nuclear β-catenin accumulation, regardless of histological severity. Expression of Cav1, Trp53 was differentially regulated in the distal colon of Winnie relative to wild-type mice. Expression of Myc and Ccl5 was increased by DSS treatment in Winnie only. Furthermore, increased Ccl5 expression correlated with increased complexity in abnormal crypts. While no overall difference in Cxcl5 mucosal expression was observed between treatment groups, epithelial Cxcl5 protein appeared to be diminished in the atypical epithelium.
CONCLUSION Alterations to the expression of Cav1, Ccl5, Myc and Trp53 in the chronically inflamed Winnie colon may influence the transition to dysplasia.
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Morosin T, Ashford B, Ranson M, Gupta R, Clark J, Iyer NG, Spring K. Circulating tumour cells in regionally metastatic cutaneous squamous cell carcinoma: A pilot study. Oncotarget 2016; 7:47111-47115. [PMID: 27302928 PMCID: PMC5216927 DOI: 10.18632/oncotarget.9946] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 04/16/2016] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Circulating tumour cells (CTCs) are increasingly being used in the surveillance of cancer, allowing for potential early detection and real-time monitoring of disease progression. The presence of CTCs in patients with metastatic cutaneous head and neck squamous cell carcinoma (cHNSCC) has not been evaluated. RESULTS CTCs were detected in eight of ten patients with regional metastatic cHNSCC (80%; range 1-44 cells/9 mL blood). CTMs were detected in three of ten patients (30%, range 1-4 cells/9 mL blood). METHODS Preoperative blood samples from ten patients with nodal metastases from cutaneous squamous cell carcinomas (cSCC) were analyzed using the IsoFluxTM System for the detection and enumeration of CTCs and circulating tumour microemboli (CTMs). CONCLUSIONS For the first time CTCs have been detected in patients with nodal metastases from cHNSCC. Further work is required to understand their prognostic significance and potential to directly influence clinical practice.
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Affiliation(s)
- Tia Morosin
- Graduate School of Medicine, University of Wollongong, Wollongong, NSW 2522, Australia
| | - Bruce Ashford
- School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health and Medical Research Institute (IHMRI), Wollongong, NSW 2522, Australia
- Illawarra and Shoalhaven Local Health District (ISLHD), Wollongong, NSW 2522, Australia
- Centre for Oncology Education and Research Translation (CONCERT), Liverpool, NSW 2170, Australia
| | - Marie Ranson
- School of Biological Sciences, University of Wollongong, Wollongong, NSW 2522, Australia
- Illawarra Health and Medical Research Institute (IHMRI), Wollongong, NSW 2522, Australia
- Centre for Oncology Education and Research Translation (CONCERT), Liverpool, NSW 2170, Australia
| | - Ruta Gupta
- Department of Tissue Pathology and Diagnostic Oncology, Royal Prince Alfred Hospital, Camperdown, NSW 2050, Australia
- The University of Sydney, Sydney, NSW 2006, Australia
| | - Jonathan Clark
- Sydney Head and Neck Cancer Institute, Department of Head and Neck Surgery, The Chris O'Brien Lifehouse, Camperdown, NSW 2050, Australia
- Central Clinical School, The University of Sydney, Sydney, NSW 2006, Australia
- South West Clinical School, Faculty of Medicine, The University of New South Wales, Sydney, NSW 2052, Australia
- Singhealth/Duke-NUS Head and Neck Center, National Cancer Center Singapore (NCCS), 169610, Singapore
| | - N. Gopalakrishna Iyer
- Medical Oncology Group, Ingham Institute for Applied Medical Research, Liverpool, NSW 2170, Australia
| | - Kevin Spring
- Centre for Oncology Education and Research Translation (CONCERT), Liverpool, NSW 2170, Australia
- South West Clinical School, Faculty of Medicine, The University of New South Wales, Sydney, NSW 2052, Australia
- Liverpool Clinical School, Western Sydney University, Liverpool, NSW 1871, Australia
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Lim SH, De Souza P, Chua W, Ng W, Harris B, Cowley MJ, Spring K. Abstract 1942: Change in serum microRNA expression during neoadjuvant chemoradiation for rectal cancer. Cancer Res 2016. [DOI: 10.1158/1538-7445.am2016-1942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Introduction
MicroRNAs (miRNA) expression may change with treatment and influence responses in locally advanced rectal cancer (LARC) making them potentially useful predictive and prognostic biomarkers. We investigated 112 miRNAs in serum during chemoradiation for LARC.
Methods
Twenty-one patients with LARC treated with neoadjuvant chemoradiation were prospectively recruited for the study. Serum was collected at three time-points: 1) at diagnosis (baseline), 2) at three weeks into treatment and 3) at completion of chemoradiation (pre-surgery). Serum was also collected from 10 healthy controls. RNA extraction was performed using the Norgen™ total RNA purification kit. Reverse transcription and pre-amplification were performed as per the Taqman™ OpenArray MicroRNA Panels manufacturer's instructions. miRNA array qPCR was performed on 112 miRNA targets using the QuantStudio™ 12K platform. Differentially expressed miRNAs were identified using the delta-delta-Ct method, using the endogenous U6 snRNA as the control. Analysis was performed in R, using paired t-statistics, and the Benjamini-Hochberg False Discovery Rate for multiple hypothesis testing adjustment, with a threshold q<0.05 for significant differential expression. Enriched KEGG pathways were identified using DIANA, based on verified gene targets of each miRNA from Tarbase.
Results
We identified 12 miRNAs that were significantly differentially expressed between patients and matched controls. The strongest differences were observed between patient samples at baseline and completion of chemoradiation, where eight miRNAs decreased in expression: hsa-miR-101, hsa-miR-130a, hsa-miR-130b, hsa-miR-223, hsa-miR-27a, hsa-miR-628-5p, hsa-miR-630 and hsa-miR-720, all with fold change > 3-fold. These genes are known to target key rectal cancer genes such as SMAD4, BCL2, MSH2 and TGFBR2. An additional three miRNAs changed significantly between baseline and week 3: hsa-miR-135b*, hsa-miR-375 and hsa-miR-629. All except hsa-miR-135b* became less abundant.
Conclusions
Ten differentially expressed miRNAs appear downregulated during chemoradiation in LARC. These miRNAs have been implicated in cell proliferation, the epithelial-mesenchymal transition and radiation resistance. Further work will be undertaken to understand the functional implications of these changes.
Citation Format: Stephanie H. Lim, Paul De Souza, Wei Chua, Weng Ng, Benjamin Harris, Mark J. Cowley, Kevin Spring. Change in serum microRNA expression during neoadjuvant chemoradiation for rectal cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1942.
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Affiliation(s)
| | | | - Wei Chua
- 1Liverpool Hospital, Liverpool, Australia
| | - Weng Ng
- 1Liverpool Hospital, Liverpool, Australia
| | | | - Mark J. Cowley
- 3Kinghorn Centre for Clinical Genomics, Darlinghurst, Australia
| | - Kevin Spring
- 4Ingham Institute for Applied Medical Research, Liverpool, Australia
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Lim S, Spring K, Chua W, Ng W, Descallar J, Ma Y, Becker T, De Souza P. Circulating Tumor Cells in Locally Advanced Rectal Cancer Treated With Neoadjuvant Chemoradiation. Int J Radiat Oncol Biol Phys 2015. [DOI: 10.1016/j.ijrobp.2015.07.1883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Lim S, Chua W, Ng W, Descallar J, Bokey L, Spring K, De Souza P. 2172 Presence of circulating tumour cells and correlation with inflammatory markers in non-metastatic rectal cancer. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31092-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Lim S, Ng W, Chua W, Descallar J, Spring K, De Souza P. 1558 Quality of life and circulating tumour cells in patients treated with neoadjuvant chemoradiation for rectal cancer - is there a link? Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)30648-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Spring K, Lim S, Descallar J, Ng W, Chua W, de Souza P, Bokey L, MacKenzie S. P-300 Circulating tumour cell release in the peri-operative setting during curative colorectal cancer surgery. Ann Oncol 2015. [DOI: 10.1093/annonc/mdv233.297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Kalimutho M, Simmons J, Fernando W, Saunus J, Spring K, Lakhani S, Al-Ejeh F, Khanna KK. Abstract LB-116: Cep55, a master regulator of cytokinesis in breast cancer pathogenesis. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-lb-116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Defects in the number, structure, and function of centrosomes can generate mono- or multipolar mitotic spindles and cytokinesis failure resulting in aneuploidy and chromosome instability, which are common characteristics of tumour cells. Centrosomal proteins thus play central roles in the execution of proper cell division. Cep55 is a centrosomal protein required for proper segregation of two daughter cells during cytokinesis. It often elevated in wide range of cancer types including breast cancer. To ascertain the functional role of Cep55 in breast cancer pathogenesis, we performed publically available data mining as well as IHC staining in a cohort of breast cancer patients and found that elevated levels of Cep55 is significantly associated with p53 mutation, basal like subtype, relapse free and distant-metastasis free survival. Immunoblot analysis of non-malignant and breast cancer cell lines revealed higher expression of Cep55 protein in basal like subtype. RNAi mediated Cep55 depletion in cultured human breast cancer cells resulted in decreased cell proliferation, induction of apoptosis in-vitro and failure to establish xenografts in-vivo. Moreover, these cells failed to establish lung colonisation due to less proliferative, migrative and invasive capacity in experimental metastasis models. In an initial effort to identify causal effective of Cep55 mediated breast cancer pathogenesis, we found that Cep55-depleted cells that survive following long term culture have restored their ploidy compared with aneuploid cells that have constitutively high levels of Cep55. Moreover, these non-tumorigenic cells also have defect in major signalling networks assessed by Kinexus proteomic array. In line with this finding, we found that constitutive overexpression of Cep55 in non-transformed mammary epithelial cells, MCF-10a induced ERK1/2 and STAT3 signalling possibly due to increase in chromosome instability. Taken together, these results indicate that Cep55 promotes breast cancer initiation, progression and lung colonisation through pleiotropic effect and genomic instability that likely contribute to aneuploidy state of breast cancer tumours
Citation Format: Murugan Kalimutho, Jacinta Simmons, Winnie Fernando, Jodi Saunus, Kevin Spring, Sunil Lakhani, Fares Al-Ejeh, Kum Kum Khanna. Cep55, a master regulator of cytokinesis in breast cancer pathogenesis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-116. doi:10.1158/1538-7445.AM2014-LB-116
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Affiliation(s)
| | - Jacinta Simmons
- 1QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Winnie Fernando
- 1QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Jodi Saunus
- 2UQ Centre for Clinical Research, Brisbane, Australia
| | - Kevin Spring
- 1QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Sunil Lakhani
- 2UQ Centre for Clinical Research, Brisbane, Australia
| | - Fares Al-Ejeh
- 1QIMR Berghofer Medical Research Institute, Brisbane, Australia
| | - Kum Kum Khanna
- 1QIMR Berghofer Medical Research Institute, Brisbane, Australia
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Lim SHS, Shin JS, Tut TG, Ng WT, Chua W, Dissanayake IU, Spring K, Ng W, Bokey L, De Souza P, Lee CS. Polo-like kinase 1 as a biomarker in rectal cancers. J Clin Oncol 2014. [DOI: 10.1200/jco.2014.32.15_suppl.e14542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | - J-S Shin
- Department of Anatomical Pathology, Liverpool Hospital, Liverpool, Australia
| | - T G Tut
- Liverpool Clinical School, School of Medicine, University of Western Sydney, Liverpool, Australia
| | - W T.W. Ng
- Liverpool Clinical School, School of Medicine, University of Western Sydney, Liverpool, Australia
| | - Wei Chua
- Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia
| | - I U Dissanayake
- Liverpool Clinical School, School of Medicine, University of Western Sydney, Liverpool, Australia
| | - Kevin Spring
- Ingham Institute for Applied Medical Research, Liverpool, Australia
| | - Weng Ng
- Department of Medical Oncology, Liverpool Hospital, Liverpool, Australia
| | - Les Bokey
- Liverpool Clinical School, School of Medicine, University of Western Sydney, Liverpool, Australia
| | - Paul De Souza
- Ingham Institute for Applied Medical Research, Liverpool, Australia
| | - C S Lee
- Department of Anatomical Pathology, Liverpool Hospital, Liverpool, Australia
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Walsh MD, Buchanan DD, Pearson SA, Clendenning M, Jenkins MA, Win AK, Walters RJ, Spring K, Nagler B, Pavluk E, Arnold ST, Goldblatt J, George J, Suthers G, Phillips K, Hopper JL, Jass JR, Baron JA, Ahnen D, Thibodeau S, Lindor N, Parry S, Walker N, Rosty C, Young JP. Immunohistochemical testing of conventional adenomas for loss of expression of mismatch repair proteins in Lynch syndrome mutation carriers: a case series from the Australasian site of the colon cancer family registry. Mod Pathol 2012; 25:722-30. [PMID: 22322191 PMCID: PMC3477239 DOI: 10.1038/modpathol.2011.209] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Debate continues as to the usefulness of assessing adenomas for loss of mismatch repair protein expression to identify individuals with suspected Lynch syndrome. We tested 109 polyps from 69 proven mutation carriers (35 females and 34 males) belonging to 49 Lynch syndrome families. All polyps were tested by immunohistochemistry for four mismatch repair proteins MLH1, MSH2, MSH6 and PMS2. Detailed pathology review was performed by specialist gastrointestinal pathologists. The majority of polyps (86%) were conventional adenomas (n=94), with 65 tubular and 28 tubulovillous adenomas and a single villous adenoma. The remaining 15 lesions (14%) were serrated polyps. Overall, loss of mismatch repair expression was noted for 78/109 (72%) of polyps. Loss of mismatch repair expression was seen in 74 of 94 (79%) conventional adenomas, and 4 of 15 (27%) serrated polyps from mismatch repair gene mutation carriers. In all instances, loss of expression was consistent with the underlying germline mutation. Mismatch repair protein expression was lost in 27 of 29 adenomas with a villous component compared with 47 of 65 adenomas without this feature (93 vs 73%; P=0.028). A strong trend was observed for high-grade dysplasia. Mismatch repair deficiency was observed in 12 of 12 conventional adenomas with high-grade dysplasia compared with 60 of 79 with low-grade dysplasia (100 vs 76%; P=0.065). We were unable to demonstrate a significant association between conventional adenoma size or site and mismatch repair deficiency. All (4/4 or 100%) of the serrated polyps demonstrating mismatch repair deficiency were traditional serrated adenomas from a single family. Diagnostic testing of adenomas in suspected Lynch syndrome families is a useful alternative in cases where cancers are unavailable. The overwhelming majority of conventional adenomas from mutation carriers show loss of mismatch repair protein expression concordant with the underlying germline mutation.
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Affiliation(s)
- Michael D Walsh
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia,School of Medicine, University of Queensland, Herston QLD 4006, Australia
| | | | | | | | - Mark A Jenkins
- Centre for MEGA, School of Population Health, University of Melbourne, Carlton, VIC 3053, Australia
| | - Aung Ko Win
- Centre for MEGA, School of Population Health, University of Melbourne, Carlton, VIC 3053, Australia
| | | | - Kevin Spring
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia
| | - Belinda Nagler
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia
| | - Erika Pavluk
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia
| | - Sven T Arnold
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia
| | - Jack Goldblatt
- School of Paediatrics and Child Health, University of Western Australia, Nedlands, WA 6009, Australia,Genetic Services of Western Australia, Subiaco, WA 6008, Australia
| | - Jill George
- Genetic Services of Western Australia, Subiaco, WA 6008, Australia
| | - Graeme Suthers
- Department of Paediatrics, University of Adelaide, SA 5005, Australia,South Australian Clinical Genetics Service, North Adelaide, SA 5009, Australia
| | - Kerry Phillips
- South Australian Clinical Genetics Service, North Adelaide, SA 5009, Australia
| | - John L Hopper
- Centre for MEGA, School of Population Health, University of Melbourne, Carlton, VIC 3053, Australia
| | - Jeremy R Jass
- Department of Cellular Pathology, St Mark’s Hospital, Harrow, HA1 3UJ, UK
| | - John A Baron
- Department of Medicine, University of North Carolina, Chapel Hill, North Carolina, USA
| | - Dennis Ahnen
- Denver Department of Veterans Affairs Medical Center and University of Colorado School of Medicine, Denver Colorado 80220 USA
| | - Stephen Thibodeau
- Division of Laboratory Genetics, Mayo Clinic, Rochester, Minnesota USA
| | - Noralane Lindor
- Departments of Laboratory Medicine and Pathology and Medical Genetics, Mayo Clinic, Rochester, Minnesota USA
| | - Susan Parry
- New Zealand Familial Gastrointestinal Cancer Registry, Auckland City Hospital, Auckland, New Zealand
| | | | - Christophe Rosty
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia,School of Medicine, University of Queensland, Herston QLD 4006, Australia,Pathology Queensland, Royal Brisbane and Women’s Hospital, Herston QLD 4006, Australia
| | - Joanne P Young
- Familial Cancer Laboratory, QIMR, Herston QLD 4006, Australia,School of Medicine, University of Queensland, Herston QLD 4006, Australia
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Zimmermann U, Steffin B, Spring K, Uhr M, O'Connor S, Holsboer F. Ethanol effects on naloxone-induced stimulation of the hypothalamic-pituitary system in healthy human subjects. Exp Clin Endocrinol Diabetes 2004. [DOI: 10.1055/s-2004-832901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Zimmermann U, Uhr M, Spring K, Wittchen HU, Holsboer F. STRESS-INDUCED PROLACTIN SECRETION IS ATTENUATED BY ETHANOL IN SONS OF ALCOHOLIC FATHERS. Alcohol Clin Exp Res 2004. [DOI: 10.1097/00000374-200408002-00120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Zimmerman U, Spring K, Koller G, Holsboer F, Soyka M. Hypothalamic-pituitary-adrenal system regulation in recently detoxified alcoholics is not altered by one week of treatment with acamprosate. Pharmacopsychiatry 2004; 37:98-102. [PMID: 15179967 DOI: 10.1055/s-2004-818986] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND Acamprosate decreases relapse rates in alcohol-dependent patients by approximately 10-20% within the first year after detoxification. Psychological stress is a major risk fac-tor for relapse and is associated with activation of the hypothalamic-pituitary-adrenocortical (HPA) system. In recently detoxified alcoholics, the HPA system is dysregulated with non-suppression of cortisol after dexamethasone administration. We therefore investigated whether acamprosate normalizes HPA hyperactivity in alcoholics within the first 3 weeks of abstinence, employing a combined dexamethasone/corticotropin-releasing hormone (Dex-CRH)-test. METHODS Thirty alcohol-dependent patients were tested one week after withdrawal signs had disappeared. In 15 patients, acamprosate, 1332-1998 mg/day, was administered orally and a second Dex-CRH test was performed 1 week later. In the other 15 patients, acamprosate treatment was offered only after the second test. RESULTS CRH-stimulated cortisol secretion was significantly increased in both the acamprosate group and the group receiving no anti-relapse medication compared to a control group of 15 healthy subjects. Acamprosate treatment had no effect on basal or CRH-stimulated ACTH or cortisol secretion. CONCLUSIONS We conclude that 1 week of acamprosate treatment does not attenuate the HPA dysregulation ob-served during early abstinence.
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Affiliation(s)
- U Zimmerman
- Max Planck Institute of Psychiatry, Munich, Germany.
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21
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Zimmermann U, Spring K, Wittchen HU, Himmerich H, Landgraf R, Uhr M, Holsboer F. Arginine vasopressin and adrenocorticotropin secretion in response to psychosocial stress is attenuated by ethanol in sons of alcohol-dependent fathers. J Psychiatr Res 2004; 38:385-93. [PMID: 15203290 DOI: 10.1016/j.jpsychires.2003.11.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2003] [Revised: 11/17/2003] [Accepted: 11/25/2003] [Indexed: 11/26/2022]
Abstract
Familial risk and environmental stress promote the development of alcohol dependence. We investigated whether a positive family history of alcoholism affects the neuroendocrine response to a standardized laboratory stress test in healthy subjects without alcohol use disorders. Twenty-four high-risk subjects with a paternal history of alcoholism (PHA) and 16 family history negative (FHN) controls were evaluated. Psychosocial stress was induced by having subjects deliver a 5-min speech and mental arithmetics in front of an audience on separate days, after drinking either placebo or ethanol (0.6 g/kg) in a randomized sequence. Adrenocorticotropin (ACTH) was measured in 10 plasma samples covering up to 75 min after the stress test. Plasma arginine vasopressin (AVP) was determined before the stressor, at the time of maximum ACTH secretion, and at 75 min after stress onset. The stress test induced a phasic increase in ACTH secretion. At the time of maximum ACTH, AVP was significantly increased in relation to baseline. Compared to placebo, alcohol administration significantly attenuated maximum ACTH concentration in PHA but not FHN subjects, and decreased AVP measured in the same samples in PHA but not FHN subjects. We conclude that activation of the hypothalamic-pituitary-adrenal system by psychosocial stress is accompanied by an increase in peripheral plasma AVP levels. Secretion of both ACTH and AVP suggest that alcohol attenuates the stress response selectively in PHA but not FHN subjects. This might imply some short-term positive alcohol effect in sons of alcoholics, but also constitute a mechanism by which their risk to develop alcohol use disorders is increased.
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Affiliation(s)
- U Zimmermann
- Max-Planck Institute of Psychiatry, Kraepelinstrasse 10, 80804 Munich, Germany.
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Chen P, Peng C, Luff J, Spring K, Watters D, Bottle S, Furuya S, Lavin MF. Oxidative stress is responsible for deficient survival and dendritogenesis in purkinje neurons from ataxia-telangiectasia mutated mutant mice. J Neurosci 2003; 23:11453-60. [PMID: 14673010 PMCID: PMC6740509] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023] Open
Abstract
Atm gene-disrupted mice recapitulate the majority of characteristics observed in patients with the genetic disorder ataxia-telangiectasia (A-T). However, although they exhibit defects in neuromotor function and a distinct neurological phenotype, they do not show the progressive neurodegeneration seen in human patients, but there is evidence that ataxia-telangiectasia mutated (Atm)-deficient animals have elevated levels of oxidized macromolecules and some neuropathology. We report here that in vitro survival of cerebellar Purkinje cells from both Atm "knock-out" and Atm "knock-in" mice was significantly reduced compared with their wild-type littermates. Although most of the Purkinje neurons from wild-type mice exhibited extensive dendritic elongation and branching under these conditions, most neurons from Atm-deficient mice had dramatically reduced dendritic branching. An antioxidant (isoindoline nitroxide) prevented Purkinje cell death in Atm-deficient mice and enhanced dendritogenesis to wild-type levels. Furthermore, administration of the antioxidant throughout pregnancy had a small enhancing effect on Purkinje neuron survival in Atm gene-disrupted animals and protected against oxidative stress in older animals. These data provide strong evidence for a defect in the cerebellum of Atm-deficient mice and suggest that oxidative stress contributes to this phenotype.
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Affiliation(s)
- Philip Chen
- The Queensland Institute of Medical Research, Royal Brisbane Hospital, Herston, Queensland 4029, Australia
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23
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Abstract
Several members of the phosphatidylinositol 3-kinase family play key roles in recognising and responding to damage in DNA, induced by a variety of chemicals and other agents. One of these, ATM, the product of the gene mutated in the human genetic disorder ataxia-telangiectasia (A-T), recognises double strand breaks in DNA caused by ionizing radiation and radiomimetic chemicals. In order to study DNA damage recognition and the abnormalities of genome instability and cancer predisposition that occur in A-T patients, we generated a mouse model expressing a mutant form of Atm corresponding to a common human mutation. In this model, a 9 nucleotide in-frame deletion was introduced into the Atm gene and has been designated Atm-Delta SRI. These animals had a longer lifespan than Atm gene disrupted mice (Atm(-/-)) and they developed less thymic lymphomas. A characteristic of the lymphomas appearing in Atm-Delta SRI mice was an increased rate of apoptosis compared to the corresponding tumours in Atm(-/-) mice. Increased expression of FasL in these tumours may account for the higher levels of apoptosis. These results demonstrate that expression of mutant Atm in mice gives rise to phenotypic differences compared to Atm(-/-) mice and has implications for heterogeneity described in the human syndrome.
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Affiliation(s)
- Martin F Lavin
- The Queensland Cancer Fund Research Laboratories, The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Herston, Brisbane, Qld. 4029, Australia.
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Young J, Barker M, Fraser L, Walsh MD, Spring K, Biden KG, Hopper JL, Leggett BA, Jass JR. Mutation searching in colorectal cancer studies: experience with a denaturing high-pressure liquid chromatography system for exon-by-exon scanning of tumour suppressor genes. Pathology 2002; 34:529-33. [PMID: 12555990 DOI: 10.1080/0031302021000035965-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [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: 02/02/2023]
Abstract
AIMS In hereditary colorectal cancer (CRC) disorders such as familial adenomatous polyposis and hereditary non-polyposis colon cancer, the identification of germline mutations greatly assists in the clinical management of families. In addition, study of somatic mutations in the cancers themselves (both hereditary and sporadic) has been fundamental in the elucidation of the initiation and progression of CRC. Many of the genes underlying CRC development are large; hence mutation screening is a time-consuming and labour-intensive process requiring a rapid and accurate alternative to gel-based systems such as single-strand confirmational polymorphism (SSCP) or denaturing gradient gel electrophoresis (DGGE). Here we report our progress using denaturing gradient high-pressure liquid chromatography (DHPLC) in the screening of the mismatch repair genes MLH1 and MSH2 and in screening the APC and HPP1 tumour suppressor genes for mutations. METHODS Genomic DNA was amplified using intronic primer sets spanning individual exons in the gene(s) under study. PCR products were subjected to DHPLC and the resultant chromatographs were compared with those of normal controls and aberrant peaks identified. Amplified products with aberrant peaks in the study samples underwent manual sequencing to confirm the presence of sequence variants. RESULTS The proportion of amplified fragments showing aberrant peaks (hits) ranged from 18 to 30% and in the case of every gene, more than 80% of these could be confirmed as a sequence variant by manual sequencing. The highest rate was found in HPP1, where all hits were found to be sequence variants, and the lowest rate was found in MSH2, where manual sequencing failed to find a sequence variant in 17% of the hits attained. Mutations varied in their nature from directly truncating through splice variants to missense and deletion mutations. Traces for each mutation displayed unique shapes and both deletions and single base changes were equally dramatic. During the mutation scanning many polymorphisms presented as aberrant peaks, as would be expected. Importantly, the same polymorphism gave an identical chromatographic tracing between individuals, opening the possibility to identify common polymorphisms on pattern recognition alone. There remains, though, the possibility that rare pathogenic variants may assume an identical shape. CONCLUSIONS The results indicate that DHPLC is a sensitive and efficient technique for screening of DNA for sequence variants. Given that polymorphisms comprised the largest proportion of variants found in each gene (66-100%), excluding these by pattern recognition would markedly reduce the amount of sequencing required.
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Affiliation(s)
- Joanne Young
- Conjoint Gastroenterology Laboratory, Royal Brisbane Hospital Foundation Clinical Research Centre, Bancroft Centre, Herston, Queensland, Australia.
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Shibata DM, Sato F, Mori Y, Perry K, Yin J, Wang S, Xu Y, Olaru A, Selaru F, Spring K, Young J, Abraham JM, Meltzer SJ. Hypermethylation of HPP1 is associated with hMLH1 hypermethylation in gastric adenocarcinomas. Cancer Res 2002; 62:5637-40. [PMID: 12384516] [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] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
The HPP1 gene was initially discovered because of its frequent hypermethylation in hyperplastic colon polyps, but it is also hypermethylated in colorectal adenomas and carcinomas. Expression of the DNA mismatch repair gene hMLH1 is diminished or absent in some hyperplastic polyps, and it has been suggested that HPP1 inactivation is associated with the progression of microsatellite-unstable colorectal tumors. We sought then to determine the prevalence of HPP1 silencing by DNA methylation in gastric adenocarcinomas and to define any association of this event with microsatellite instability (MSI) or hMLH1 hypermethylation. Thirty-two matched normal-gastric adenocarcinoma DNA pairs were studied for MSI status and hypermethylation of HPP1 and hMLH1. Five (100%) of 5 MSI-H tumors, 2 (50%) of 4 MSI-L tumors, and 8 (35%) of 23 MSS tumors demonstrated HPP1 hypermethylation. Eight (25%) of 32 tumors (5 of 5 MSI-H, 2 of 4 MSI-L, and 1 of 23 MSS) showed evidence of hMLH1 hypermethylation. All (8 of 8) of these hMLHI-methylated tumors demonstrated concomitant methylation at the HPP1 locus: there were no cases of hMLH1 methylation occurring in the absence of HPP1 methylation. In gastric adenocarcinoma, hypermethylation frequently targets HPP1. Moreover, hMLH1 hypermethylation occurs predominantly in the setting of HPP1 hypermethylation. HPP1 hypermethylation may represent an early event in mismatch repair-deficient gastric tumorigenesis.
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Affiliation(s)
- David M Shibata
- Division of Surgical Oncology, Department of Surgery, University of Maryland School of Medicine, Baltimore 21201, USA
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Spring K, Ahangari F, Scott SP, Waring P, Purdie DM, Chen PC, Hourigan K, Ramsay J, McKinnon PJ, Swift M, Lavin MF. Mice heterozygous for mutation in Atm, the gene involved in ataxia-telangiectasia, have heightened susceptibility to cancer. Nat Genet 2002; 32:185-90. [PMID: 12195425 DOI: 10.1038/ng958] [Citation(s) in RCA: 120] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ataxia-telangiectasia is characterized by radiosensitivity, genome instability and predisposition to cancer. Heterozygous carriers of ATM, the gene defective in ataxia-telangiectasia, have a higher than normal risk of developing breast and other cancers. We demonstrate here that Atm 'knock-in' (Atm-Delta SRI) heterozygous mice harboring an in-frame deletion corresponding to the human 7636del9 mutation show an increased susceptibility to developing tumors. In contrast, no tumors are observed in Atm knockout (Atm(+/-)) heterozygous mice. In parallel, we report the appearance of tumors in 6 humans from 12 families who are heterozygous for the 7636del9 mutation. Expression of ATM cDNA containing the 7636del9 mutation had a dominant-negative effect in control cells, inhibiting radiation-induced ATM kinase activity in vivo and in vitro. This reduces the survival of these cells after radiation exposure and enhances the level of radiation-induced chromosomal aberrations. These results show for the first time that mouse carriers of a mutated Atm that are capable of expressing Atm have a higher risk of cancer. This finding provides further support for cancer predisposition in human ataxia-telangiectasia carriers.
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Affiliation(s)
- Kevin Spring
- Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Herston, 4029, Australia
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27
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Spring K, Cross S, Li C, Watters D, Ben-Senior L, Waring P, Ahangari F, Lu SL, Chen P, Misko I, Paterson C, Kay G, Smorodinsky NI, Shiloh Y, Lavin MF. Atm knock-in mice harboring an in-frame deletion corresponding to the human ATM 7636del9 common mutation exhibit a variant phenotype. Cancer Res 2001; 61:4561-8. [PMID: 11389091] [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: 02/20/2023]
Abstract
ATM, the gene mutated in the human immunodeficiency disorder ataxia-telangiectasia (A-T), plays a central role in recognizing ionizing radiation damage in DNA and in controlling several cell cycle checkpoints. We describe here a murine model in which a nine-nucleotide in-frame deletion has been introduced into the Atm gene by homologous recombination followed by removal of the selectable marker cassette by Cre-loxP site-specific, recombination-mediated excision. This mouse, Atm-DeltaSRI, was designed as a model of one of the most common deletion mutations (7636del9) found in A-T patients. The murine Atm deletion results in the loss of three amino acid residues (SRI; 2556-2558) but produces near full-length detectable Atm protein that lacks protein kinase activity. Radiosensitivity was observed in Atm-DeltaSRI mice, whereas the immunological profile of these mice showed greater heterogeneity of T-cell subsets than observed in Atm(-/-) mice. The life span of Atm-DeltaSRI mice was significantly longer than that of Atm(-/-) mice when maintained under nonspecific pathogen-free conditions. This can be accounted for by a lower incidence of thymic lymphomas in Atm-DeltaSRI mice up to 40 weeks, after which time the animals died of other causes. The thymic lymphomas in Atm-DeltaSRI mice were characterized by extensive apoptosis, which appears to be attributable to an increased number of cells expressing Fas ligand. A variety of other tumors including B-cell lymphomas, sarcomas, and carcinomas not seen in Atm(-/-) mice were observed in older Atm-DeltaSRI animals. Thus, expression of mutant protein in Atm-DeltaSRI knock-in mice gives rise to a discernibly different phenotype to Atm(-/-) mice, which may account for the heterogeneity seen in A-T patients with different mutations.
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Affiliation(s)
- K Spring
- Queensland Cancer Fund Research Laboratories, The Queensland Institute of Medical Research, P.O. Box Royal Brisbane Hospital, Herston, Brisbane, Queensland 4029, Australia
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Hundt W, Zimmermann U, Pottig M, Spring K, Holsboer F. The Combined Dexamethasone-Suppression/CRH-Stimulation Test in Alcoholics During and After Acute Withdrawal. Alcohol Clin Exp Res 2001. [DOI: 10.1111/j.1530-0277.2001.tb02268.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Fillippovich I, Sorokina N, Gatei M, Haupt Y, Hobson K, Moallem E, Spring K, Mould M, McGuckin MA, Lavin MF, Khanna KK. Transactivation-deficient p73alpha (p73Deltaexon2) inhibits apoptosis and competes with p53. Oncogene 2001; 20:514-22. [PMID: 11313982 DOI: 10.1038/sj.onc.1204118] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [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: 08/02/2000] [Revised: 11/13/2000] [Accepted: 11/16/2000] [Indexed: 11/09/2022]
Abstract
p73 has recently been identified as a structural and functional homolog of the tumor suppressor protein p53. Overexpression of p53 activates transcription of p53 effector genes, causes growth inhibition and induced apoptosis. We describe here the effects of a tumor-derived truncated transcript of p73alpha (p73Deltaexon2) on p53 function and on cell death. This transcript, which lacks the acidic N-terminus corresponding to the transactivation domain of p53, was initially detected in a neuroblastoma cell line. Overexpression of p73Deltaexon2 partially protects lymphoblastoid cells against apoptosis induced by anti-Fas antibody or cisplatin. By cotransfecting p73Deltaexon2 with wild-type p53 in the p53 null line Saos 2, we found that this truncated transcript reduces the ability of wild-type p53 to promote apoptosis. This anti-apoptotic effect was also observed when p73Deltaexon2 was co-transfected with full-length p73 (p73alpha). This was further substantiated by suppression of p53 transactivation of the effector gene p21/Waf1 in p73Deltaexon2 transfected cells and by inhibition of expression of a reporter gene under the control of the p53 promoter. Thus, this truncated form of p73 can act as a dominant-negative agent towards transactivation by p53 and p73alpha, highlighting the potential implications of these findings for p53 signaling pathway. Furthermore, we demonstrate the existence of a p73Deltaexon2 transcript in a very significant proportion (46%) of breast cancer cell lines. However, a large spectrum of normal and malignant tissues need to be surveyed to determine whether this transdominant p73 variant occurs in a tumor-specific manner.
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Affiliation(s)
- I Fillippovich
- Laboratory of Molecular Radiobiology, Institute of Biophysics, Russian Ministry of Health, Moscow, 123182, Russia
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Yang T, Park JM, Arend L, Huang Y, Topaloglu R, Pasumarthy A, Praetorius H, Spring K, Briggs JP, Schnermann J. Low chloride stimulation of prostaglandin E2 release and cyclooxygenase-2 expression in a mouse macula densa cell line. J Biol Chem 2000; 275:37922-9. [PMID: 10982805 DOI: 10.1074/jbc.m006218200] [Citation(s) in RCA: 139] [Impact Index Per Article: 5.8] [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: 01/13/2023] Open
Abstract
Reducing luminal NaCl concentration in the macula densa region of the nephron stimulates renin secretion, and this response is blocked by a specific inhibitor of cyclooxygenase-2 (COX-2) (Traynor, T. R., Smart, A., Briggs, J. P., and Schnermann, J. (1999) Am. J. Physiol. Renal Physiol. 277, F706-710). To study whether low NaCl activates COX-2 activity or expression we clonally derived a macula densa cell line (MMDD1 cells) from SV-40 transgenic mice using fluorescence-activated cell sorting of renal tubular cells labeled with segment-specific fluorescent lectins. MMDD1 cells express COX-2, bNOS, NKCC2, and ROMK, but not Tamm-Horsfall protein, and showed rapid (86)Rb(+) uptake that was inhibited by a reduction in NaCl concentration and by bumetanide or furosemide. Isosmotic exposure of MMDD1 cells to low NaCl (60 mm) caused a prompt and time-dependent stimulation of prostaglandin E(2) (PGE(2)) release that was prevented by the COX-2 specific inhibitor NS-398 (10 microm). Reducing NaCl to 60 and 6 mm for 16 h increased COX-2 expression in a chloride-dependent fashion. Low NaCl phosphorylated p38 kinase within 30 min and ERK1/2 kinases within 15 min without changing total MAP kinase levels. Low NaCl-stimulated PGE(2) release and COX-2 expression was inhibited by SB 203580 and PD 98059 (10 microm), inhibitors of p38 and ERK kinase pathways. We conclude that low chloride stimulates PGE(2) release and COX-2 expression in MMDD1 cells through activation of MAP kinases.
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Affiliation(s)
- T Yang
- NIDDK and NHLBI, National Institutes of Health, Bethesda, Maryland 20892, USA
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Gatei M, Young D, Cerosaletti KM, Desai-Mehta A, Spring K, Kozlov S, Lavin MF, Gatti RA, Concannon P, Khanna K. ATM-dependent phosphorylation of nibrin in response to radiation exposure. Nat Genet 2000; 25:115-9. [PMID: 10802669 DOI: 10.1038/75508] [Citation(s) in RCA: 352] [Impact Index Per Article: 14.7] [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: 11/08/2022]
Abstract
Mutations in the gene ATM are responsible for the genetic disorder ataxia-telangiectasia (A-T), which is characterized by cerebellar dysfunction, radiosensitivity, chromosomal instability and cancer predisposition. Both the A-T phenotype and the similarity of the ATM protein to other DNA-damage sensors suggests a role for ATM in biochemical pathways involved in the recognition, signalling and repair of DNA double-strand breaks (DSBs). There are strong parallels between the pattern of radiosensitivity, chromosomal instability and cancer predisposition in A-T patients and that in patients with Nijmegen breakage syndrome (NBS). The protein defective in NBS, nibrin (encoded by NBS1), forms a complex with MRE11 and RAD50 (refs 1,2). This complex localizes to DSBs within 30 minutes after cellular exposure to ionizing radiation (IR) and is observed in brightly staining nuclear foci after a longer period of time. The overlap between clinical and cellular phenotypes in A-T and NBS suggests that ATM and nibrin may function in the same biochemical pathway. Here we demonstrate that nibrin is phosphorylated within one hour of treatment of cells with IR. This response is abrogated in A-T cells that either do not express ATM protein or express near full-length mutant protein. We also show that ATM physically interacts with and phosphorylates nibrin on serine 343 both in vivo and in vitro. Phosphorylation of this site appears to be functionally important because mutated nibrin (S343A) does not completely complement radiosensitivity in NBS cells. ATM phosphorylation of nibrin does not affect nibrin-MRE11-RAD50 association as revealed by radiation-induced foci formation. Our data provide a biochemical explanation for the similarity in phenotype between A-T and NBS.
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Affiliation(s)
- M Gatei
- The Queensland Institute of Medical Research, PO Royal Brisbane Hospital, Brisbane, Queensland, Australia
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Zhou BB, Chaturvedi P, Spring K, Scott SP, Johanson RA, Mishra R, Mattern MR, Winkler JD, Khanna KK. Caffeine abolishes the mammalian G(2)/M DNA damage checkpoint by inhibiting ataxia-telangiectasia-mutated kinase activity. J Biol Chem 2000; 275:10342-8. [PMID: 10744722 DOI: 10.1074/jbc.275.14.10342] [Citation(s) in RCA: 221] [Impact Index Per Article: 9.2] [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: 11/06/2022] Open
Abstract
Recent evidence indicates that arrest of mammalian cells at the G(2)/M checkpoint involves inactivation and translocation of Cdc25C, which is mediated by phosphorylation of Cdc25C on serine 216. Data obtained with a phospho-specific antibody against serine 216 suggest that activation of the DNA damage checkpoint is accompanied by an increase in serine 216 phosphorylated Cdc25C in the nucleus after exposure of cells to gamma-radiation. Prior treatment of cells with 2 mM caffeine inhibits such a change and markedly reduces radiation-induced ataxia-telangiectasia-mutated (ATM)-dependent Chk2/Cds1 activation and phosphorylation. Chk2/Cds1 is known to localize in the nucleus and to phosphorylate Cdc25C at serine 216 in vitro. Caffeine does not inhibit Chk2/Cds1 activity directly, but rather, blocks the activation of Chk2/Cds1 by inhibiting ATM kinase activity. In vitro, ATM phosphorylates Chk2/Cds1 at threonine 68 close to the N terminus, and caffeine inhibits this phosphorylation with an IC(50) of approximately 200 microM. Using a phospho-specific antibody against threonine 68, we demonstrate that radiation-induced, ATM-dependent phosphorylation of Chk2/Cds1 at this site is caffeine-sensitive. From these results, we propose a model wherein caffeine abrogates the G(2)/M checkpoint by targeting the ATM-Chk2/Cds1 pathway; by inhibiting ATM, it prevents the serine 216 phosphorylation of Cdc25C in the nucleus. Inhibition of ATM provides a molecular explanation for the increased radiosensitivity of caffeine-treated cells.
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Affiliation(s)
- B B Zhou
- Department of Oncology Research, SmithKline Beecham Pharmaceuticals, King of Prussia, Pennsylvania 19406, USA.
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Watters D, Kedar P, Spring K, Bjorkman J, Chen P, Gatei M, Birrell G, Garrone B, Srinivasa P, Crane DI, Lavin MF. Localization of a portion of extranuclear ATM to peroxisomes. J Biol Chem 1999; 274:34277-82. [PMID: 10567403 DOI: 10.1074/jbc.274.48.34277] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The gene mutated in the human genetic disorder ataxia-telangiectasia codes for a protein, ATM, the known functions of which include response to DNA damage, cell cycle control, and meiotic recombination. Consistent with these functions, ATM is predominantly present in the nucleus of proliferating cells; however, a significant proportion of the protein has also been detected outside the nucleus in cytoplasmic vesicles. To understand the possible role of extra-nuclear ATM, we initially investigated the nature of these vesicles. In this report we demonstrate that a portion of ATM co-localizes with catalase, that ATM is present in purified mouse peroxisomes, and that there are reduced levels of ATM in the post-mitochondrial membrane fraction of cells from a patient with a peroxisome biogenesis disorder. Furthermore the use of the yeast two-hybrid system demonstrated that ATM interacts directly with a protein involved in the import of proteins into the peroxisome matrix. Because peroxisomes are major sites of oxidative metabolism, we investigated catalase activity and lipid hydroperoxide levels in normal and A-T fibroblasts. Significantly decreased catalase activity and increased lipid peroxidation was observed in several A-T cell lines. The localization of ATM to peroxisomes may contribute to the pleiotropic nature of A-T.
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Affiliation(s)
- D Watters
- Cancer Research Unit, Queensland Institute of Medical Research, Royal Brisbane Hospital, Herston, Brisbane, Australia, 4029.
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Zhang N, Chen P, Khanna KK, Scott S, Gatei M, Kozlov S, Watters D, Spring K, Yen T, Lavin MF. Isolation of full-length ATM cDNA and correction of the ataxia-telangiectasia cellular phenotype. Proc Natl Acad Sci U S A 1997; 94:8021-6. [PMID: 9223307 PMCID: PMC21549 DOI: 10.1073/pnas.94.15.8021] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A gene mutated in the human genetic disorder ataxia-telangiectasia (A-T), ATM, was recently identified by positional cloning. ATM is a member of the phosphatidylinositol-3-kinase superfamily, some of which are protein kinases and appear to have important roles in cell cycle control and radiation signal transduction. We describe herein, to our knowledge, for the first time, the cloning of a full-length cDNA for ATM and correction of multiple aspects of the radio-sensitive phenotype of A-T cells by transfection with this cDNA. Overexpression of ATM cDNA in A-T cells enhanced the survival of these cells in response to radiation exposure, decreased radiation-induced chromosome aberrations, reduced radio-resistant DNA synthesis, and partially corrected defective cell cycle checkpoints and induction of stress-activated protein kinase. This correction of the defects in A-T cells provides further evidence of the multiplicity of effector functions of the ATM protein and suggests possible approaches to gene therapy.
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Affiliation(s)
- N Zhang
- The Queensland Institute of Medical Research, The Bancroft Centre, 300 Herston Road, Herston, Brisbane, Queensland 4029, Australia
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Shafman T, Khanna KK, Kedar P, Spring K, Kozlov S, Yen T, Hobson K, Gatei M, Zhang N, Watters D, Egerton M, Shiloh Y, Kharbanda S, Kufe D, Lavin MF. Interaction between ATM protein and c-Abl in response to DNA damage. Nature 1997; 387:520-3. [PMID: 9168117 DOI: 10.1038/387520a0] [Citation(s) in RCA: 370] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The gene mutated in the autosomal recessive disorder ataxia telangiectasia (AT), designated ATM (for 'AT mutated'), is a member of a family of phosphatidylinositol-3-kinase-like enzymes that are involved in cell-cycle control, meiotic recombination, telomere length monitoring and DNA-damage response. Previous results have demonstrated that AT cells are hypersensitive to ionizing radiation and are defective at the G1/S checkpoint after radiation damage. Because cells lacking the protein tyrosine kinase c-Abl are also defective in radiation-induced G1 arrest, we investigated the possibility that ATM might interact with c-Abl in response to radiation damage. Here we show that ATM binds c-Abl constitutively in control cells but not in AT cells. Our results demonstrate that the SH3 domain of c-Abl interacts with a DPAPNPPHFP motif (residues 1,373-1,382) of ATM. The results also reveal that radiation-induction of c-Abl tyrosine kinase activity is diminished in AT cells. These findings indicate that ATM is involved in the activation of c-Abl by DNA damage and this interaction may in part mediate radiation-induced G1 arrest.
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Affiliation(s)
- T Shafman
- Joint Center for Radiation Therapy, Dana Farber Cancer Institutes, Boston, Massachusetts 02115, USA
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Watters D, Khanna KK, Beamish H, Birrell G, Spring K, Kedar P, Gatei M, Stenzel D, Hobson K, Kozlov S, Zhang N, Farrell A, Ramsay J, Gatti R, Lavin M. Cellular localisation of the ataxia-telangiectasia (ATM) gene product and discrimination between mutated and normal forms. Oncogene 1997; 14:1911-21. [PMID: 9150358 DOI: 10.1038/sj.onc.1201037] [Citation(s) in RCA: 142] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The recently cloned gene (ATM) mutated in the human genetic disorder ataxia-telangiectasia (A-T) is involved in DNA damage response at different cell cycle checkpoints and also appears to have a wider role in signal transduction. Antibodies prepared against peptides from the predicted protein sequence detected a approximately 350 kDa protein corresponding to the open reading frame, which was absent in 13/23 A-T homozygotes. Subcellular fractionation, immunoelectronmicroscopy and immunofluorescence showed that the ATM protein is present in the nucleus and cytoplasmic vesicles. This distribution did not change after irradiation. We also provide evidence that ATM protein binds to p53 and this association is defective in A-T cells compatible with the defective p53 response in these cells. These results provide further support for a role for the ATM protein as a sensor of DNA damage and in a more general role in cell signalling, compatible with the broader phenotype of the syndrome.
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Affiliation(s)
- D Watters
- Queensland Institute of Medical Research, P.O. Royal Brisbane Hospital, Herston, Australia
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Khanna KK, Yan J, Watters D, Hobson K, Beamish H, Spring K, Shiloh Y, Gatti RA, Lavin MF. Defective signaling through the B cell antigen receptor in Epstein-Barr virus-transformed ataxia-telangiectasia cells. J Biol Chem 1997; 272:9489-95. [PMID: 9083089 DOI: 10.1074/jbc.272.14.9489] [Citation(s) in RCA: 34] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
A characteristic series of immunological abnormalities are observed in the human genetic disorder ataxia-telangiectasia (A-T). The recent cloning of a gene mutated in this syndrome provides additional evidence for a defect in intracellular signaling in A-T. We have investigated the possibility that signaling through the B cell antigen receptor is one manifestation of the A-T defect. In response to cross-linking of the B cell receptor, several A-T cell lines were defective in their mitogenic response; in addition Ca2+ mobilization from internal stores was either absent or considerably reduced in these cell lines in response to cross-linking. The defect in signaling was not due to difference in expression of surface immunoglobulin. The defective response in A-T cells was also evident in several arms of the intracellular cascade activated by B cell cross-linking. Tyrosine phosphorylation of phospholipase Cgamma1, a key step in activation of the enzyme, was reduced or negligible in some A-T cell lines. This defect in signaling was also seen at the level of Lyn tyrosine kinase activation and its association with and activation of phosphatidylinositol 3-kinase. Our results provide evidence for a role for the ATM gene product in intracellular signaling which may account at least in part for the abnormalities in B cell function in A-T.
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Affiliation(s)
- K K Khanna
- Queensland Cancer Fund Research Unit, Queensland Institute of Medical Research, P.O. Royal Brisbane Hospital, Herston, Brisbane 4029, Australia.
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Lavin MF, Khanna KK, Beamish H, Spring K, Watters D, Shiloh Y. Relationship of the ataxia-telangiectasia protein ATM to phosphoinositide 3-kinase. Trends Biochem Sci 1995; 20:382-3. [PMID: 8533147 DOI: 10.1016/s0968-0004(00)89083-0] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- M F Lavin
- Queensland Institute of Medical Research, Bancroft Centre, Herston, Brisbane, Australia
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Zadunaisky J, Spring K, Sellers J, Robison W, Cardona S. Contraction and area change of human trabecular meshwork cells in tissue cultures. Exp Eye Res 1992. [DOI: 10.1016/0014-4835(92)90658-f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Rand KN, Moore T, Sriskantha A, Spring K, Tellam R, Willadsen P, Cobon GS. Cloning and expression of a protective antigen from the cattle tick Boophilus microplus. Proc Natl Acad Sci U S A 1989; 86:9657-61. [PMID: 2690068 PMCID: PMC298560 DOI: 10.1073/pnas.86.24.9657] [Citation(s) in RCA: 158] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Glycoproteins located on the luminal surface of the plasma membrane of tick gut epithelial cells, when used to vaccinate cattle, are capable of stimulating an immune response that protects cattle against subsequent tick infestation. One such tick gut glycoprotein, designated Bm86, has been purified to homogeneity and the amino acid sequences of peptide fragments generated by endoproteinase Lys-C digestion have been determined. We report here the isolation and characterization of a cDNA that encodes Bm86. The nucleotide sequence of the cDNA contains a 1982-base-pair open reading frame and predicts that Bm86 contains 650 amino acids including a 19-amino acid signal sequence and a 23-amino acid hydrophobic region adjacent to the carboxyl terminus. The main feature of the deduced protein sequence is the repeated pattern of 6 cysteine residues, suggesting the presence of several epidermal growth factor-like domains. A fusion protein consisting of 599 amino acids of Bm86 and 651 amino acids of beta-galactosidase was expressed in Escherichia coli as inclusion bodies. Ticks engorging on cattle vaccinated with these inclusion bodies were significantly damaged as a result of the immune response against the cloned antigen.
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Affiliation(s)
- K N Rand
- Biotechnology Australia Pty. Ltd., Roseville, New South Wales
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Whittembury G, Diezi F, Diezi J, Spring K, Giebisch G. Some aspects of proximal tubular sodium chloride reabsorption in Necturus kidney. Kidney Int 1975; 7:293-30. [PMID: 237133 DOI: 10.1038/ki.1975.42] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Some aspects of proximal tubular sodium chloride reabsorption in Necturus kidney. Renal tubular reabsorption of fluid and sodium was measured by clearance methods in the doubly perfused Necturus kidney in which the bicarbonate concentration was varied between 0 and 60 mEq/liter. The effects of Damox (2.2 times 10-3M), ocubain (10-5M) and ethacrynic acid (10-4M) and of acidosis were also investigated. In addition to clearance experiments, stationary microperfusion experiments were carried out on promimal tubules to measure volume flow and steady-state sodium and chloride concentration differences across the tubular epithelium. In some experiments, the transepithelial electrical potential difference was also measured using an axial electrode system. The following results were obtained: 1) Bicarbonate is not essential to the operation of renal tubular fluid and sodium transport. 2) Total renal and proximal tubular fluid and sodium transport are partially inhibited by Diamox, ouabian and ethacrynic acid. 3) The proximal tubule maintains a significant transepithelial sodium and chloride concentration difference and a significant electrical potential difference (lumen-negative) in the presence of a poorly permeant nonelectrolyte. The direction and magnitude of the electrical polarization fully accounts for the observed chloride concentration difference. The data support the thesis that sodium chloride transport accross the proximal tubular epithelium takes place by active sodium transport and electically coupled passive chloride reabsorption. Important species differences with respect to mammalian transport mechanisms are discussed.
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