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Lewandowska M.A.,Center of Oncology of Poland | Lewandowska M.A.,Nicolaus Copernicus University
International Journal of Clinical and Experimental Pathology | Year: 2013

Proper gene splicing is highly dependent on the correct recognition of exons. Among the elements allowing this process are the "cis" (conserved sequences) and "trans" (snRNP, splicing factors) elements. Splicing mutations are related with a number of genetic disorders and usually induce exon skipping, form new exon/intron boundaries or activate new cryptic exons as a result of alterations at donor/acceptor sites. They constitute more than 9% of the currently published mutations, but this value is highly underestimated as many of the potential mutations are located in the "cis" elements and should be confirmed experimentally. The most commonly detected splicing mutations are located at donor (5') and acceptor (3') sites. Mutations at the branch point are rare (only over a dozen are known to date), and are mostly searched and detected when no alteration has been detected in the sequenced exons and UTRs. Polypyrimidine tract mutations are equally rare. High throughput technologies, as well as traditional Sanger sequencing, allow detection of many changes in intronic sequences and intron/exon boundaries. However, the assessment whether a mutation affects exon recognition and results in a genetic disorder has to be conducted using molecular biology methods: in vitro transcription of the sequence of interest cloned into a plasmid, with and without alterations, or mutation analysis via a hybrid minigene system. Even though microarrays and new generation sequencing methods pose difficulties in detecting novel branch point mutations, these tools seem appropriate to expand the mutation detection panel especially for diagnostic purposes.

Maciejczyk A.,Center of Oncology of Poland
Advances in Clinical and Experimental Medicine | Year: 2013

For many years, the age of the patient, the condition of axillar lymph nodes, the size of the tumour, histological traits (in particular histological grade of malignancy and invasion of lymphatic vessels), condition of hormonal receptors and HER2 represented principal factors used for the stratification of breast cancer patients for the purposes of evaluating the prognosis and determining the appropriate strategy of treatment. Although the variables are useful for the prognostic evaluation of individual groups of breast cancer patients, their role in determining the individual risk level of the patient and in the selection of supplementary treatment is quite restricted. This article shows the prognostic value of additional parameters, whose expression is associated with chemioresistance (MRP2, BCRP, YB1) or individual assessment of the dynamics of tumor progression (S100P, BUBR1). In addition, it describes the role of an online database of "The Kaplan-Meier plotter" which contains the assessment of the effects of expression of various genes on the clinical outcome of patients with breast cancer. © Copyright by Wrocław Medical University.

A comprehensive review of the histological classification and genetics of serrated colorectal lesions and their relationship with CRC is presented. Sessile serrated lesions might be precursors in approximately one third of CRC cases. The criteria for the diagnosis of HPSP, its incidence, and relationship with CRC are provided and thoroughly discussed. The most recent guidelines for colonoscopy surveillance after screening and polypectomy concerning both serrated lesions and conventional adenomas presented by expert panels are provided. Copyright © 2013 by the American Society for Gastrointestinal Endoscopy.

Niwinska A.,Center of Oncology of Poland | Murawska M.,Erasmus Medical Center
International Journal of Radiation Oncology Biology Physics | Year: 2012

Purpose: The aim of the study was to present a new breast cancer recursive partitioning analysis (RPA) prognostic index for patients with newly diagnosed brain metastases as a guide in clinical decision making. Methods and Materials: A prospectively collected group of 441 consecutive patients with breast cancer and brain metastases treated between the years 2003 and 2009 was assessed. Prognostic factors significant for univariate analysis were included into RPA. Results: Three prognostic classes of a new breast cancer RPA prognostic index were selected. The median survival of patients within prognostic Classes I, II, and III was 29, 9, and 2.4 months, respectively (p < 0.0001). Class I included patients with one or two brain metastases, without extracranial disease or with controlled extracranial disease, and with Karnofsky performance status (KPS) of 100. Class III included patients with multiple brain metastases with KPS of ≤60. Class II included all other cases. Conclusions: The breast cancer RPA prognostic index is an easy and valuable tool for use in clinical practice. It can select patients who require aggressive treatment and those in whom whole-brain radiotherapy or symptomatic therapy is the most reasonable option. An individual approach is required for patients from prognostic Class II. © 2012 Elsevier Inc.

Roszkowski K.,Center of Oncology of Poland
Frontiers in Bioscience - Landmark | Year: 2014

Oxidative stress represents a deregulation of the homeostasis between the reactive oxygen species and the mechanisms of detoxification and repair. By analyzing the level of oxidatively damaged DNA bases and nucleosides in urine we can assess the extent of DNA repair within the whole body. High levels of markers of oxidative DNA damage excreted in the urine indicate elevated levels of oxidative stress, but can also reflect a high level of efficiency of the processes that work to repair this damage (oxidative stress can be high and the repair processes eliminate its effects). In the present review we discuss the role of oxidative stress, oxidative DNA damage repair mechanisms, potential sources of 8-oxoGua and 8-oxodG (basic markers of oxidative stress) content in urine, effect of antioxidant supplementation on the levels of oxidative DNA lesions, potential application of oxidative DNA damage determination in clinical practice.

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