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Featured researches published by Martin K. Oehler.


Lancet Oncology | 2010

Quality of life after total laparoscopic hysterectomy versus total abdominal hysterectomy for stage I endometrial cancer (LACE): a randomised trial

Monika Janda; Val Gebski; Alison Brand; Russel Hogg; Tom Jobling; Russel Land; Tom Manolitsas; Anthony McCartney; Marcelo Nascimento; Deborah Neesham; James L. Nicklin; Martin K. Oehler; Geoff Otton; Lewis Perrin; Stuart Salfinger; Ian Hammond; Yee Leung; Tom Walsh; Peter Sykes; Hys Ngan; Andrea Garrett; Michael Laney; Tong Yow Ng; Kar-Fai Tam; Karen Chan; C. David Wrede; Selvan Pather; Bryony Simcock; Rhonda Farrell; Andreas Obermair

BACKGROUND This two-stage randomised controlled trial, comparing total laparoscopic hysterectomy (TLH) with total abdominal hysterectomy (TAH) for stage I endometrial cancer (LACE), began in 2005. The primary objective of stage 1 was to assess whether TLH results in equivalent or improved quality of life (QoL) up to 6 months after surgery compared with TAH. The primary objective of stage 2 was to test the hypothesis that disease-free survival at 4.5 years is equivalent for TLH and TAH. Here, we present the results of stage 1. METHODS Between Oct 7, 2005, and April 16, 2008, 361 participants were enrolled in the QoL substudy at 19 centres across Australia, New Zealand, and Hong Kong; 332 completed the QoL analysis. Randomisation was done centrally and independently from other study procedures via a computer-generated, web-based system (providing concealment of the next assigned treatment), using stratified permuted blocks of three and six patients. Patients with histologically confirmed stage I endometrioid adenocarcinoma and Eastern Cooperative Oncology Group performance status less than 2 were randomly assigned to TLH (n=190) or TAH (n=142), stratified by histological grade and study centre. Patients and study personnel were not masked to treatment assignment. QoL was measured at baseline, 1 and 4 weeks (early), and 3 and 6 months (late) after surgery, using the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire. The primary endpoint was the difference between groups in QoL change from baseline at early and late timepoints (a 5% difference was considered clinically significant). Analysis was done according to the intention-to-treat principle. Patients for both stages of the trial have now been recruited and are being followed up for disease-specific outcomes. The LACE trial is registered with ClinicalTrials.gov, number NCT00096408. FINDINGS Eight of 332 patients (2.4%) had treatment conversion-seven from TLH to TAH and one from TAH to TLH (patient preference). In the early phase of recovery, patients who had TLH reported significantly greater improvement in QoL from baseline compared with those who had TAH, in all subscales apart from emotional and social wellbeing. Improvements in QoL up to 6 months after surgery continued to favour TLH, except in the emotional and social wellbeing measures of FACT and the visual analogue scale of the EuroQoL five dimensions (EuroQoL-VAS). Operating time was significantly longer in the TLH group (138 min [SD 43]) than in the TAH group (109 min [34]; p=0.001). Although the proportion of intraoperative adverse events was similar between groups (TAH eight of 142 [5.6%] vs TLH 14 of 190 [7.4%]; p=0.53); postoperatively, twice as many patients in the TAH group experienced adverse events of grade 3 or higher (33 of 142 [23.2%] vs 22 of 190 [11.6%] in the TLH group; p=0.004). Postoperative serious adverse events occurred more in the TAH group (27 of 142 [19.0%]) than in the TLH group (16 of 190 [7.9%]; p=0.002). INTERPRETATION QoL improvements from baseline during early and later phases of recovery, and the adverse event profile, favour TLH compared with TAH for treatment of stage I endometrial cancer. FUNDING Cancer Council Queensland, Cancer Council New South Wales, Cancer Council Victoria, Cancer Council Western Australia; NHMRC project grant 456110; Cancer Australia project grant 631523; The Women and Infants Research Foundation, Western Australia; Royal Brisbane and Womens Hospital Foundation; Wesley Research Institute; Gallipoli Research Foundation; Gynetech; TYCO Healthcare, Australia; Johnson and Johnson Medical, Australia; Hunter New England Centre for Gynaecological Cancer; Genesis Oncology Trust; and Smart Health Research Grant QLD Health.


Cancer Microenvironment | 2011

The Role of Annexin A2 in Tumorigenesis and Cancer Progression

Noor A. Lokman; Miranda P. Ween; Martin K. Oehler; Carmela Ricciardelli

Annexin A2 is a calcium-dependent, phospholipid-binding protein found on various cell types. It is up-regulated in various tumor types and plays multiple roles in regulating cellular functions, including angiogenesis, proliferation, apoptosis, cell migration, invasion and adhesion. Annexin A2 binds with plasminogen and tissue plasminogen activator on the cell surface, which leads to the conversion of plasminogen to plasmin. Plasmin is a serine protease which plays a key role in the activation of metalloproteinases and degradation of extracellular matrix components essential for metastatic progression. We have recently found that both annexin A2 and plasmin are increased in conditioned media of co cultured ovarian cancer and peritoneal cells. Our studies suggest that annexin A2 is part of a tumor-host signal pathway between ovarian cancer and peritoneal cells which promotes ovarian cancer metastasis. Accumulating evidence suggest that interactions between annexin A2 and its binding proteins play an important role in the tumor microenvironment and act together to enhance cancer metastasis. This article reviews the current knowledge on the biological role of annexin A2 and its binding proteins in solid malignancies including ovarian cancer.


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1998

Risk factors associated with preterm (<37+0 weeks) and early preterm birth (<32+0 weeks): univariate and multivariate analysis of 106 345 singleton births from the 1994 statewide perinatal survey of Bavaria

Joachim Martius; Thomas Steck; Martin K. Oehler; Karl-H Wulf

OBJECTIVE The study was conducted to identify medical, obstetrical and social risk factors associated with early preterm births (<32+0 gestational weeks). STUDY DESIGN The Statewide Perinatal Survey of Bavaria is a collection of perinatal data from all Bavarian maternity units using a uniform numbered questionnaire. Data on 106345 singleton births from the 1994 Survey were analysed using univariate and multivariate logistic regression analysis. RESULTS In the multivariate analysis, early preterm birth was associated with premature rupture of the membranes (odds ratio (OR) 1.6, 95% confidence interval (CI) 1.37-1.86), treatment for infertility (OR 1.7, 95% CI 1.19-2.34), previous induced abortion (OR 1.8, 95% CI 1.57-2.13), maternal age >35 years (OR 1.8, 95% CI 1.47-2.16), premature cervical dilatation (OR 2.3, 95% CI 1.86-2.94), a history of stillbirth (OR 3.2, 95% CI 2.13-4.83), a history of preterm birth (OR 3.3, 95% CI 2.45-4.48), maternal age <18 years (OR 3.4, 95% CI 2.03-5.61), malpresentation (OR 3.9, 95% CI 3.10-4.93), preeclampsia (OR 4.0, 95% CI 3.20-4.94), uterine bleeding (OR 5.0, 95% CI 4.08-6.02), preterm labour (OR 7.0, 95% CI 5.94-8.22), and chorioamnionitis (OR 22.3, 95% CI 17.40-28.66). CONCLUSION These data identify a subgroup of women at an increased risk for early preterm birth and may benefit from an intensified prenatal care. Risk factors related to the obstetrical history, genital infections, preeclampsia and maternal age are the most relevant for early preterm birth.


Acta Obstetricia et Gynecologica Scandinavica | 2003

Menorrhagia: an update

Martin K. Oehler; M. C. P. Rees

Menorrhagia is defined as a ‘complaint of heavy cyclical menstrual bleeding occurring over several consecutive cycles’. Objectively it is a total menstrual blood loss equal to or greater than 80 ml per menstruation. It is estimated that approximately 30% of women complain of menorrhagia. Excessive bleeding is the main presenting complaint in women referred to gynecologists and it accounts for two‐thirds of all hysterectomies, and most of endoscopic endometrial destructive surgery. Thus, menorrhagia is an important healthcare problem. Its etiology, investigation, medical and surgical management are described. In approximately 50% of cases of menorrhagia no pathology is found at hysterectomy. Abnormal levels of prostaglandins or the fibrinolytic system in the endometrium have been implicated. Effective medical treatments suitable for long‐term use include intrauterine progestogens, antifibrinolytic agents (tranexamic acid) and nonsteroidal anti‐inflammatory agents (mefenamic acid). Over the past decade there has been increasing use of endometrial destructive techniques as an alternative to hysterectomy. Their further refinement and the advent of fibroid embolization has increased the options available to women.


Oncogene | 2001

Adrenomedullin inhibits hypoxic cell death by upregulation of Bcl-2 in endometrial cancer cells: a possible promotion mechanism for tumour growth

Martin K. Oehler; C. Norbury; Margaret Rees; Roy Bicknell

Regions of hypoxia are a common feature of solid tumours. When tumour cells are exposed to hypoxic stress, transcription of a battery of genes is initiated. The angiogenic factor adrenomedullin (ADM) is a hypoxia regulated gene. ADM is thought to act through the G protein-coupled receptor calcitonin receptor-like receptor (CRLR), with specificity being conferred by the receptor associated modifying protein 2 (RAMP2). Here we report for the first time that ADM treated or stably transfected Ishikawa cells overexpressing ADM show increased resistance to hypoxia induced apoptosis. These cells also show an upregulation of the oncoprotein Bcl-2, which is protective against hypoxic cell death when transiently transfected into Ishikawa cells. Since Ishikawa cells express the putative ADM-receptor CRLR–RAMP2 the production and secretion of ADM with the consecutive upregulation of Bcl-2 could establish an autocrine/paracrine mechanism rescuing malignant cells from hypoxic cell death. These results, taken together with our previous findings that ADM is an angiogenic factor which is upregulated by the nonsteroidal antiestrogen tamoxifen (TAM) in endometrial cells, implicate this peptide as a promoter of tumour growth and a possible target for anticancer strategies.


International Journal of Molecular Sciences | 2012

Chick Chorioallantoic Membrane (CAM) Assay as an In Vivo Model to Study the Effect of Newly Identified Molecules on Ovarian Cancer Invasion and Metastasis

Noor A. Lokman; Alison Sf. Elder; Carmela Ricciardelli; Martin K. Oehler

The majority of ovarian cancer patients present with advanced disease and despite aggressive treatment, prognosis remains poor. Significant improvement in ovarian cancer survival will require the development of more effective molecularly targeted therapeutics. Commonly, mouse models are used for the in vivo assessment of potential new therapeutic targets in ovarian cancer. However, animal models are costly and time consuming. Other models, such as the chick embryo chorioallantoic membrane (CAM) assay, are therefore an attractive alternative. CAM assays have been widely used to study angiogenesis and tumor invasion of colorectal, prostate and brain cancers. However, there have been limited studies that have used CAM assays to assess ovarian cancer invasion and metastasis. We have therefore developed a CAM assay protocol to monitor the metastatic properties of ovarian cancer cells (OVCAR-3, SKOV-3 and OV-90) and to study the effect of potential therapeutic molecules in vivo. The results from the CAM assay are consistent with cancer cell motility and invasion observed in in vitro assays. Our results demonstrate that the CAM assay is a robust and cost effective model to study ovarian cancer cell metastasis. It is therefore a very useful in vivo model for screening of potential novel therapeutics.


Journal of Proteome Research | 2010

Citric Acid Antigen Retrieval (CAAR) for Tryptic Peptide Imaging Directly on Archived Formalin-Fixed Paraffin-Embedded Tissue

Johan O. R. Gustafsson; Martin K. Oehler; Peter Hoffmann

Imaging mass spectrometry (IMS) is a powerful technology for mapping distributions of biological molecules like proteins and peptides within tissue sections. It is therefore potentially extremely useful for the analysis of pathological conditions such as neoplastic diseases. The use of IMS is typically limited to fresh frozen tissue specimens. However, there is a high interest in the possibility of being able to analyze the tissue proteome of formalin-fixed paraffin-embedded (FFPE) specimens that have been stored together with the clinicopathological information of patients in huge archives over many decades. We have therefore developed an antigen-retrieval protocol using a high temperature citric acid buffer to allow partial reversal of FFPE protein cross-linking. Coupled with automated deposition of trypsin and matrix, our method allows the generation of meaningful peptide ion distribution images. In situ peptide fragmentation provided identification of high abundance proteins such as Actin and Collagen. Furthermore, downstream application of three different HPLC-MS strategies allowed identification of a maximum of 106 proteins, 67 of which were mass correlated to ions from IMS analysis of archived FFPE ovarian tissue. The CAAR method presented here complements previously described antigen-retrieval protocols and is an important step in being able to fully analyze the proteome of archived FFPE tissue.


Oncogene | 2002

Adrenomedullin promotes formation of xenografted endometrial tumors by stimulation of autocrine growth and angiogenesis.

Martin K. Oehler; Margaret Rees; Roy Bicknell

The angiogenic peptide adrenomedullin (ADM) has been implicated as a mediator of the increased risk of endometrial hyperplasia and cancer resulting from the use of tamoxifen for the treatment and prevention of breast cancer. ADM has been shown to be induced by tamoxifen in the endometrium and to be a growth factor for endometrial endothelial cells in vitro. We have now shown ADM to be strongly angiogenic in the mouse subcutaneous sponge angiogenesis assay. To examine the role of ADM in tumor growth, the ADM cDNA was transfected into endometrial carcinoma cells followed by xenografting into athymic mice. Two endometrial cancer cell lines were employed, those in which transfection and expression of ADM resulted in no effect on growthin vitro (Ishikawa cells) and those in which expressionof exogenous ADM stimulated in vitro growth (RL95.2 cells). A clear enhancement of tumor growth was seen with both cell lines but the effect was far greater with the RL95.2 cells. We conclude that ADM is pro-tumorigenic by stimulating either angiogenesis alone or by stimulating angiogenesis and carcinoma cell growth directly. The combined activities lead to a striking increase in tumor growth. These results provide the first direct evidence of tumorigenic activity of ADM and provide further support for ADMs involvement in tamoxifen induced endometrial neoplasia.


Journal of Clinical Oncology | 2014

Tumor Mismatch Repair Immunohistochemistry and DNA MLH1 Methylation Testing of Patients With Endometrial Cancer Diagnosed at Age Younger Than 60 Years Optimizes Triage for Population-Level Germline Mismatch Repair Gene Mutation Testing

Daniel D. Buchanan; Yen Y. Tan; Michael D. Walsh; Mark Clendenning; Alexander M. Metcalf; Kaltin Ferguson; Sven Arnold; Bryony A. Thompson; Felicity Lose; Michael T. Parsons; Rhiannon J. Walters; Sally-Ann Pearson; Margaret C. Cummings; Martin K. Oehler; Penelope Blomfield; Michael A. Quinn; Judy Kirk; Colin J.R. Stewart; Andreas Obermair; Joanne Young; Penelope M. Webb; Amanda B. Spurdle

PURPOSE Clinicopathologic data from a population-based endometrial cancer cohort, unselected for age or family history, were analyzed to determine the optimal scheme for identification of patients with germline mismatch repair (MMR) gene mutations. PATIENTS AND METHODS Endometrial cancers from 702 patients recruited into the Australian National Endometrial Cancer Study (ANECS) were tested for MMR protein expression using immunohistochemistry (IHC) and for MLH1 gene promoter methylation in MLH1-deficient cases. MMR mutation testing was performed on germline DNA of patients with MMR-protein deficient tumors. Prediction of germline mutation status was compared for combinations of tumor characteristics, age at diagnosis, and various clinical criteria (Amsterdam, Bethesda, Society of Gynecologic Oncology, ANECS). RESULTS Tumor MMR-protein deficiency was detected in 170 (24%) of 702 cases. Germline testing of 158 MMR-deficient cases identified 22 truncating mutations (3% of all cases) and four unclassified variants. Tumor MLH1 methylation was detected in 99 (89%) of 111 cases demonstrating MLH1/PMS2 IHC loss; all were germline MLH1 mutation negative. A combination of MMR IHC plus MLH1 methylation testing in women younger than 60 years of age at diagnosis provided the highest positive predictive value for the identification of mutation carriers at 46% versus ≤ 41% for any other criteria considered. CONCLUSION Population-level identification of patients with MMR mutation-positive endometrial cancer is optimized by stepwise testing for tumor MMR IHC loss in patients younger than 60 years, tumor MLH1 methylation in individuals with MLH1 IHC loss, and germline mutations in patients exhibiting loss of MSH6, MSH2, or PMS2 or loss of MLH1/PMS2 with absence of MLH1 methylation.


International Journal of Molecular Sciences | 2011

MALDI Imaging Mass Spectrometry (MALDI-IMS)―Application of Spatial Proteomics for Ovarian Cancer Classification and Diagnosis

Johan O. R. Gustafsson; Martin K. Oehler; Andrew Ruszkiewicz; Peter Hoffmann

MALDI imaging mass spectrometry (MALDI-IMS) allows acquisition of mass data for metabolites, lipids, peptides and proteins directly from tissue sections. IMS is typically performed either as a multiple spot profiling experiment to generate tissue specific mass profiles, or a high resolution imaging experiment where relative spatial abundance for potentially hundreds of analytes across virtually any tissue section can be measured. Crucially, imaging can be achieved without prior knowledge of tissue composition and without the use of antibodies. In effect MALDI-IMS allows generation of molecular data which complement and expand upon the information provided by histology including immuno-histochemistry, making its application valuable to both cancer biomarker research and diagnostics. The current state of MALDI-IMS, key biological applications to ovarian cancer research and practical considerations for analysis of peptides and proteins on ovarian tissue are presented in this review.

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Yee Leung

St John of God Health Care

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Penelope M. Webb

QIMR Berghofer Medical Research Institute

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Monika Janda

Queensland University of Technology

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