The role of ATM and 53BP1 as predictive markers in cervical cancer

Treatment of advanced-stage cervical cancers with (chemo)radiation causes cytotoxicity through induction of high levels of DNA damage. Tumour cells respond to DNA damage by activation of the DNA damage response (DDR), which induces DNA repair and may counteract chemoradiation efficacy. Here, we investigated DDR components as potential therapeutic targets and verified the predictive and prognostic value of DDR activation in patients with cervical cancer treated with (chemo)radiation. In a panel of cervical cancer cell lines, inactivation of ataxia telangiectasia mutated (ATM) or its substrate p53-binding protein-1 (53BP1) clearly gave rise to cell cycle defects in response to irradiation. Concordantly, clonogenic survival analysis revealed that ATM inhibition, but not 53BP1 depletion, strongly radiosensitised cervical cancer cells. In contrast, ATM inhibition did not radiosensitise non-transformed epithelial cells or non-transformed BJ fibroblasts. Interestingly, high levels of active ATM prior to irradiation were related with increased radioresistance. To test whether active ATM in tumours prior to treatment also resulted in resistance to therapy, immunohistochemistry was performed on tumour material of patients with advanced-stage cervical cancer (n = 375) treated with (chemo)radiation. High levels of phosphorylated (p-)ATM [p = 0.006, hazard ratio (HR) = 1.817] were related to poor locoregional disease-free survival. Furthermore, high levels of p-ATM predicted shorter disease-specific survival (p = 0.038, HR = 1.418). The presence of phosphorylated 53BP1 was associated with p-ATM (p = 0.001, odds ratio = 2.206) but was not related to any clinicopathological features or survival. In conclusion, both our in vitro and patient-related findings indicate a protective role for ATM in response to (chemo)radiation in cervical cancer and point at ATM inhibition as a possible means to improve the efficacy of (chemo)radiation

Phenotyping of non Hodgkins's lymphomas. A model for lymphoid differentiation and tumorprogression

The possibility to manufacture large quantities of monoclonal antibodies has opened new fields in lymphoma research and diagnostic pathology. In this thesis the results of the study of the immunological profile, morphology and in part clinical behavior of a large series of non Hodgkin's lymphomas are presented. Zie: Summary

Inclusion of malignant fibrous histiocytoma in the tumour spectrum associated with hereditary non-polyposis colorectal cancer

Sarcomas, including the malignant fibrous histiocytomas (MFHs), are not known to be part of the tumour spectrum of hereditary non-polyposis colorectal cancer (HNPCC) as epidemiologically established. Therefore, occurrence of MFH in an HNPCC family may very well be coincidental. HNPCC is associated with germline mutations in DNA mismatch repair genes, including the MSH2 gene. We analysed an MFH diagnosed in a 45-year-old male HNPCC patient carrying a germline MSH2 mutation for HNPCC-associated molecular characteristics, to investigate a possible relationship between the tumour and that mutation. DNA analysis revealed microsatellite instability and loss of one MSH2 copy, and immunohistochemistry showed absence of nuclear MSH2 protein staining. To investigate whether this is a common finding in MFH, microsatellite instability and nuclear MSH2 protein staining was tested for in 5 and 6 sporadic MFHs, respectively. None showed microsatellite instability and all stained positively for MSH2. Together, these findings show that in rare cases, MFH may be part of the HNPCC tumour spectrum. (C) 2000 Wiley-Liss, Inc

Stopping ovarian cancer screening in BRCA1/2 mutation carriers: Effects on risk management decisions & outcome of risk-reducing salpingo-oophorectomy specimens

Objective: Ovarian cancer screening (OCS) for BRCA1/2 mutation carriers was stopped in our family cancer clinic in 2009 because of its ineffectiveness. The study objective was to investigate the effect of stopping OCS on the timing and uptake of risk-reducing salpingo-oophorectomy (RRSO) and on the percentage of occult cancers in the specimens. Methods: 419 BRCA1/2 mutation carriers were recruited between January 1999 and June 2013. Uptake, timing and the outcome of the RRSO specimens before stopping OCS (period I) were compared to those after stopping OCS (period II). Results: The percentage of women undergoing RRSO within the recommended age range increased from 81% to 95%. Receiving DNA test results in period II independently predicted a shorter time interval to RRSO (hazard ratio: 2.48,95% confidence interval: 1.81-3.39). The incidence of detecting occult cancers in RRSO specimens before and after stopping OCS was 1.3% and 1.8%, respectively, and was not statistically significantly different. Conclusions: The presentation of risk management options to women may influence their decision. The increased patient awareness of the ineffectiveness of OCS could have led to a higher percentage of women undergoing RRSO and doing so more often within the recommended age range. (C) 2014 Elsevier Ireland Ltd. All rights reserved

Prognostic role of indoleamine 2,3-dioxygenase in endometrial carcinoma

Objective. Indoleamine-2,3-dioxygenase (IDO) suppresses the function of T-lymphocytes and is an important immune escape mechanism for cancer. Therefore, it is to be expected that IDO influences prognosis of cancer patients. This study aimed to investigate the prognostic role of IDO expression in a large cohort of endometrial carcinoma (EC) patients. Methods. A tissue microarray containing primary EC tissue of 355 patients treated in a single institution was used to evaluate IDO expression. Expression of IDO was associated with clinicopathological characteristics, survival and previously determined numbers of CD8(+) and Foxp3(+) T-lymphocytes. Results. IDOhigh expression was associated with lower numbers of intratumoral CD8(+) T-lymphocytes (p = 0.031). Next to well-known prognostic parameters, IDOhigh expression was independently associated with poor disease specific survival in the general cohort of EC patients (HR 2.62, 95% C.I. 1.48-4.66, p = 0.001) and among patients with early stage EC (HR 3.06, 95% C.I. 1.10-8.54, p = 0.032). Conclusion. Our results show that IDO expression is associated with poor survival. This provides evidence that further research into the use of IDO blocking agents in cancer treatment is valid where it might be a promising new therapeutic strategy. (c) 2012 Elsevier Inc. All rights reserved