Publications by authors named "Michał Bieńkowski"

32 Publications

Plasma amino acids indicate glioblastoma with ATRX loss.

Amino Acids 2021 Jan 4;53(1):119-132. Epub 2021 Jan 4.

Department of Neurosurgery and Neuro-Oncology, Medical University of Lodz, Barlicki University Hospital, Kopcinskiego St. 22, 90-153, Lodz, Poland.

Glioblastoma (GB) is the most common primary brain tumour in adults. The lack of molecular biomarker, non-specific symptoms and fast growth rate often result in a significant delay in diagnosis. Despite multimodal treatment, the prognosis remains poor. Here, we verified the hypothesis that amino acids (AA) regulating the critical metabolic pathways necessary for maintenance, growth, reproduction, and immunity of an organism, may constitute a favourable target in GB biomarker research. We measured the plasma amino acids levels in 18 GB patients and 15 controls and performed the quantitative and qualitative metabolomic analysis of free AA applying high-performance liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). We present both the raw data and the results of our statistical analysis. The majority of AA were lowered in the study group in comparison to the control group. Five of these (arginine, glutamic acid, glutamine, glycine, and histidine) differed significantly (all p < 10 and AUC > 0.9). Plasma levels of leucine and phenylalanine decreased in the case of GB with lost alpha-thalassemia/mental retardation X-linked (ATRX) expression on immunohistochemistry (p = 0.003 and 0.045, respectively). We demonstrated for the first time that certain plasma-free AA levels of GB patients were significantly different from those in healthy volunteers. Target profiling of plasma-free AA, identified utilizing LC-QTOF-MS, may present prognostic value by indicating GB patients with lost ATRX expression. The on-going quest for glioma biomarkers still aims to determine the detailed metabolic profile and evaluate its impact on therapy and prognosis.
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http://dx.doi.org/10.1007/s00726-020-02931-3DOI Listing
January 2021

The Role of Urine F2-ISOPROSTANE CONcentration in Delayed Cerebral Ischemia after Aneurysmal Subarachnoid Haemorrhage-A Poor Prognostic Factor.

Diagnostics (Basel) 2020 Dec 22;11(1). Epub 2020 Dec 22.

Department of Neurosurgery and Neurooncology, Barlicki University Hospital, Medical University of Lodz, Kopcińskiego 22, 90-153 Lodz, Poland.

The pathophysiology of delayed cerebral ischemia (DCI) remains unclear. One of the hypotheses suggests that reactive oxygen species play a role in its onset. Thus, we studied F2-isoprostanes (F2-IsoPs)-oxidative stress biomarkers. Our goal was to improve the early diagnosis of DCI in a non-invasive way. We conducted a prospective single center analysis of 38 aneurysmal subarachnoid hemorrhage patients. We assessed urine F2-IsoP concentration using immunoenzymatic arrays between the first and fifth day after bleeding. A correlation between urine F2-IsoP concentration and DCI occurrence was examined regarding clinical conditions and outcomes. The urine F2-IsoP concentrations were greater than those in the control groups ( < 0.001). The 3rd day urine F2-IsoPs concentrations were correlated with DCI occurrence ( < 0.001) and long term outcomes after 12 months ( < 0.001). High levels of urine F2-IsoPs on day 3 can herald DCI.
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http://dx.doi.org/10.3390/diagnostics11010005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7822020PMC
December 2020

microRNA Expression Profile in Single Hormone Receptor-Positive Breast Cancers is Mainly Dependent on HER2 Status-A Pilot Study.

Diagnostics (Basel) 2020 Aug 20;10(9). Epub 2020 Aug 20.

Department of Oncology and Radiotherapy, Medical University of Gdansk, 80-214 Gdansk, Poland.

Estrogen (ER) and progesterone (PgR) receptors and HER2 are crucial in the assessment of breast cancer specimens due to their prognostic and predictive significance. Single hormone receptor-positive breast cancers are less common and their clinical course is less favorable than ER(+)/PgR(+) tumors. Their molecular features, especially microRNA (miRNA) profiles, have not been investigated to date. Tumor specimens from 36 chemonaive breast cancer patients with known ER and PgR status (18 ER(+)/PgR(-) and 18 ER(-)/PgR(+) cases) were enrolled to the study. The expression of 829 miRNAs was evaluated with nCounter Human v3 miRNA expression Assay (NanoString). miRNAs differentiating between ER/PgR/HER2 phenotypes were selected based on fold change (FC) calculated for the mean normalized counts of each probe in compared groups. The differences were estimated with Student's -test or Two-Way ANOVA (considering also the HER2 status). The results were validated using The Cancer Genome Atlas (TCGA) dataset. Following quality control of raw data, fourcases were excluded due to low sample quality, leaving 14 ER(+)/PgR(-) and 18 ER(-)/PgR(+) cases. After correction for multiple comparisons, we did not find miRNA signature differentiating between ER(-)/PgR(+) and ER(+)/PgR(-) breast cancers. However, a trend for differing expression (-value ≤ 0.05; FDR > 0.2; ANOVA) in eight miRNAs was observed. The ER(+)/PgR(-) group demonstrated elevated levels of four miRNAs-miR-30a-5p, miR-29c-3p, miR-141-3p and miR-423-5p-while the ER(-)/PgR(+) tumors were enriched in another four miRNAs-miR-514b-5p, miR-424-5p, miR-495-3p, and miR-92a-3p. For one of the miRNAs-miR-29c-3p-the association with the ER(+)/PgR(-) phenotype was confirmed in the TCGA cohort (-value = 0.024; -test). HER2 amplification/overexpression in the NanoString cohort was related to significant differences observed in 33 miRNA expression levels (FDR ≤ 0.2; ANOVA). The association with HER2 status was confirmed in the TCGA cohort for four miRNAs (miR-1180-3p, miR-223-3p, miR-30d-5p, and miR-195-5p). The main differences in miRNA expression amongst single hormone receptor-positive tumors were identified according to their HER2 status. However, ER(+)/PgR(-) cases tended to express higher levels of miRNAs associated with ER-positivity (miR-30a-5p, miR-29c-3p, miR-141-3p), whereas ER(-)/PgR(+) cancers showed elevated levels of miRNAs characteristic for double- and triple-negative tumors (miR-92a-3p, miR-424-5p). Further studies are necessary to comprehensively analyze miRNA signatures characteristic of ER(-)/PgR(+) and ER(+)/PgR(-) tumors.
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http://dx.doi.org/10.3390/diagnostics10090617DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7555149PMC
August 2020

MAML2 rearrangement as a useful diagnostic marker discriminating between Warthin tumour and Warthin-like mucoepidermoid carcinoma.

Virchows Arch 2020 Sep 28;477(3):393-400. Epub 2020 Mar 28.

Department of Pathomorphology, Faculty of Medicine, Medical University of Gdańsk, Mariana Smoluchowskiego 17, Gdańsk, 80-214, Poland.

Warthin tumour is the second most common benign neoplasm of salivary glands. Despite its relatively characteristic histology, it may sometimes mimic other lesions. Here, we report two female non-smoker patients diagnosed with low-grade mucoepidermoid carcinoma with oncocytic epithelium and prominent lymphoid (Warthin-like) stroma and with molecularly confirmed MAML2 rearrangement. In addition, we screened a consecutive series of 114 Warthin tumour cases by means of MAML2 break apart fluorescence in situ hybridization to assess its value in differential diagnosis. MAML2 rearrangement was detected in both mucoepidermoid carcinoma cases, while all Warthin tumours were negative. Taking into account the literature data, Warthin-like mucoepidermoid carcinomas are more frequently observed in women, while a slight male predominance and smoking history are typical for Warthin tumour. In addition, the patients with Warthin-like mucoepidermoid carcinoma were significantly younger than those with Warthin tumour. To conclude, Warthin-like mucoepidermoid carcinoma may usually be suspected based on histology, while the diagnosis can be confirmed by means of molecular assays such as FISH. The investigation of MAML2 status is particularly advised when Warthin tumour is considered in a young, non-smoking, female patient.
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http://dx.doi.org/10.1007/s00428-020-02798-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7443186PMC
September 2020

Medullary thyroid carcinoma of unknown primary origin with synchronous finding of papillary thyroid carcinoma.

Endokrynol Pol 2020 25;71(2):200-201. Epub 2020 Feb 25.

Department of General, Endocrine, and Transplant Surgery, Medical University of Gdańsk, Gdańsk, Poland.

Not required for Clinical Vignette.
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http://dx.doi.org/10.5603/EP.a2020.0003DOI Listing
March 2021

Expression of Female Sex Hormone Receptors, Connective Tissue Growth Factor and HER2 in Gallbladder Cancer.

Sci Rep 2020 02 5;10(1):1871. Epub 2020 Feb 5.

Department of Oncology, Military Institute of Medicine, Warsaw, Poland.

Gallbladder cancer (GBC) is a highly malignant tumor with poorly understood etiology. An insight into phenotypic features of this malignancy may add to the knowledge of its carcinogenesis and pave the way to new therapeutic approaches. We assessed the expression of female sex hormone receptors (ERα, ERβ, PR), connective tissue growth factor (CTGF) and HER2 in GBC, and adjacent normal tissue (NT), and determined their prognostic impact. Immunohistochemical (IHC) expression of all biomarkers was performed in formalin-fixed, paraffin-embedded specimens in 60 Caucasian GBC patients (51 women and 9 men). ERβ, cytoPR and CTGF expression were found in 89%, 27%, 91% of GBC, and in 63%, 87%, 100% of NT, respectively. No ERα expression was found in GBC and NT. Strong (3+) HER2 expression by IHC or HER2 amplification was seen in five GBC (10.4%). A positive correlation was found between HER2 and CTGF and ERβ expression in GBC and matched NT. In the multivariate analysis, patient age >70 years, tumor size and ERβ expression in GBC was highly predictive for OS (p = 0.003). The correlation between HER2, CTGF and ERβ expression in GBC and NT may indicate the interaction of these pathways in physiological processes and gallbladder pathology.
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http://dx.doi.org/10.1038/s41598-020-58777-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7002405PMC
February 2020

Liquid biopsy for minimally invasive heart transplant monitoring: a pilot study.

J Clin Pathol 2020 Aug 5;73(8):507-510. Epub 2019 Dec 5.

Department of Cardiac & Vascular Surgery, Faculty of Medicine, Medical University of Gdańsk, Gdańsk, Poland.

Background: Heart transplantation allows for a long-term management of patients with end-stage heart failure. After the surgery, organ rejection is monitored with endomyocardial biopsy, which is an invasive, but not always informative procedure. Therefore, there is a pressing need for a new, safe, yet reliable, diagnostic method. Here, we present a pilot study confronting liquid biopsy based on donor-specific cell-free DNA with the protocol endomyocardial biopsy.

Methods: The study was performed on 21 blood samples matched with endomyocardial biopsy (graded according to acute cellular rejection scale) from nine patients after heart transplantation. Genotyping was performed on genomic DNA from donors and recipients for 10 single-nucleotide polymorphisms (SNPs). Cell-free DNA isolated from plasma was analysed with digital droplet PCR to detect donor-specific alleles.

Results: From 21 analysed endomyocardial biopsies, 4 were graded as 0R and 17 as 1R. Liquid biopsy was successfully performed in each sample for all informative SNPs (median of 3 per patient). We observed a high homogeneity of the results between SNPs in each sample (interclass correlation coefficient of >0.9).

Conclusions: There is a undeniable need for an alternative, non-invasive diagnostic procedure of early transplant rejection and investigation of donor-derived cell-free DNA seems to be the promising choice. The very high sensitivity is particularly enticing to consider liquid biopsy as a potential screening tool. Its minimal invasiveness may allow for more frequent examination and, thus, tighter monitoring. The reliable assessment of its clinical utility requires an adequately powered and properly designed multicentre study.
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http://dx.doi.org/10.1136/jclinpath-2019-205926DOI Listing
August 2020

Who Is a Pathologist According to Oncology Patients and Internet Users? A Survey Study.

J Cancer Educ 2021 Apr;36(2):370-376

Department of Pathology, Medical University of Gdańsk, Mariana Smoluchowskiego 17, 80-214, Gdańsk, Poland.

The pathologist is frequently called "the doctor's doctor." However, there are many uncertainties about the role of a pathologist among patients and policymakers and even among other medical specialties. The aim of the current study is to analyze the misconceptions of who a pathologist is among inpatients and Internet users, to find where the lack of understanding is originating from, and to confirm the need to educate the general public about pathologists. The survey of Internet users was conducted among Facebook users, utilizing the snowball sampling method. Inpatients were randomly recruited in the Department of Surgical Oncology. Seventy-eight inpatients and 320 Internet users were enrolled in the study. Significantly, more hospital patients than Internet users answered that the pathologist is not an MD (p = 0.00953). A portion of participants stated that pathologists do not make diagnoses (n = 28, 7.03%) and do not influence the treatment plan (n = 37, 9.30%) and that the other specialists do not gain anything from the pathologist's work (n = 67, 16.83%). Only 15.07% of respondents had their information about pathologists from other doctors. The findings from this study should show that even the most basic knowledge of a pathologist being an MD is not known. Pathologists are not recognized for being involved in the diagnosis of diseases. This should provide an incentive to pathologists to teach future doctors, policymakers, and patients about the perplexity of the pathology specialty. It shows obvious gaps in the knowledge of the treatment process as a whole.
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http://dx.doi.org/10.1007/s13187-019-01640-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7994219PMC
April 2021

MiR-21, miR-34a, miR-125b, miR-181d and miR-648 levels inversely correlate with MGMT and TP53 expression in primary glioblastoma patients.

Arch Med Sci 2019 Mar 31;15(2):504-512. Epub 2017 Jul 31.

Department of Genetics, Chair of Molecular Medicine, Faculty of Medicine, University of Rzeszow, Rzeszow, Poland.

Introduction: and alterations play a crucial role in glioblastoma (GB) pathogenesis. and function is affected by several pathologic mechanisms, such as point mutations or promoter methylation, which are well characterized. Expression of both genes can be regulated by other mechanisms as well, e.g., microRNAs (miRNAs). Moreover, cross-talk among various pathologic processes may occur, further affecting and functionality.

Material And Methods: In 49 GB patients, we analyzed the possible associations between and its miRNA regulators , , and , as well as and its miRNA regulators and . We evaluated the possible influence of mutational and methylation status on the pre-identified associations.

Results: In patients with immunohistochemistry-detected overexpression, expression levels of and were negatively correlated ( = -0.56, = 0.0195), and in patients with mutations, expression levels of and were negatively correlated ( = -0.67, = 0.0330). In patients with methylation, expression levels of were negatively correlated with and expression levels ( = -0.61, = 0.0269 and = -0.34, = 0.0727, respectively).

Conclusions: Our findings demonstrate that selected miRNAs are significantly correlated with and levels, but the extent of this correlation differs regarding the and mutational and promoter methylation status.
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http://dx.doi.org/10.5114/aoms.2017.69374DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6425218PMC
March 2019

Primarily resectable pancreatic adenocarcinoma - to operate or to refer the patient to an oncologist?

Crit Rev Oncol Hematol 2019 Mar 25;135:95-102. Epub 2019 Jan 25.

Department of Radiotherapy, School of Medicine with the Division of Dentistry in Zabrze, Medical University of Silesia, Katowice, Poland.

The aim of this work is to investigate the optimal therapeutic sequence of resectable pancreatic cancer - primary surgery with adjuvant therapy or neoadjuvant followed by resection. Application of the neoadjuvant approach in routine treatment of pancreatic cancer is rapidly growing every year, despite the lack of final results from randomized trials. Recent advancements in the adjuvant therapy, due to the more effective chemotherapy regimens, favor the upfront surgery strategy. On the other hand, theoretical background and metaanalyses favor the neoadjuvant strategy. Currently, primary resection with adjuvant chemotherapy remains the standard approach in resectable pancreatic cancer, but the first recommendations considering the neoadjuvant approach as an option seem to arise among the scientific societies with a global impact. Preliminary results of Prodige 24 study and PREOPANC-1 trial demonstrates that both options are worth further evaluation in clinical trials. Their results should soon provide more answers to this important clinical questions.
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http://dx.doi.org/10.1016/j.critrevonc.2019.01.010DOI Listing
March 2019

Isoprostanes as potential cerebral vasospasm biomarkers.

Neurol Neurochir Pol 2018 Nov - Dec;52(6):643-651. Epub 2018 Oct 4.

Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Kopcińskiego 22, 90-153 Lodz, Poland.

Despite enormous progress in medicine, symptomatic cerebral vasospasm (CVS), remains an unexplained clinical problem, which leaves both physicians and patients helpless and relying on chance, due to the lack of specific marker indicative of imminent danger as well as the lack of specific treatment. In our opinion CVS occurrence depends on dynamic disbalance between free radicals' formation (oxidative stress) and antioxidant activity. Isoprostanes are products of free-radical peroxidation of polyunsaturated fatty acids, and seem to mark a promising path for the research aiming to unravel its possible mechanism. Not only are they the biomarkers of oxidative stress in vivo and in vitro, but also have manifold biological effects (including vasoactive, inflammatory and mitogenic) via activation of the thromboxane A2 receptor (TBXA2R), both in physiological and pathophysiological processes. This review addresses the importance of isoprostanes in CVS in quest of appropriate biomarkers.
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http://dx.doi.org/10.1016/j.pjnns.2018.09.009DOI Listing
June 2019

Recurrent Pineocytomalike Papillary Tumor of The Pineal Region: A Case Report and Literature Review.

World Neurosurg 2018 Dec 27;120:1-14. Epub 2018 Aug 27.

Department of Pathology, Chair of Oncology, Medical University of Lodz, Lodz, Poland.

Background: Papillary tumors of the pineal region (PTPRs) are malignant World Health Organization grade II/III tumors; however, they may perfectly mimic benign tumors (e.g., pineocytomas [World Health Organization grade I]).

Case Description: We present a case of a 28-year-old man with a 35-mm tumor of the pineal region. Considering the typical radiological and pathologic presentation, the tumor was first diagnosed as pineocytoma. However, despite first total resection, the tumor recurred after 7 years. The recurrent neoplasm was composed mainly of papillary structures with low-grade atypical cells positive for CKAE1/AE3 and CK18. This categorization led to the final diagnosis of PTPR. The patient underwent adjuvant radiotherapy, which vastly improved his neurologic condition and resulted in significant tumor regression.

Conclusions: This case exemplifies that PTPRs can perfectly mimic pineocytomas and simple staining for cytokeratins may warrant correct diagnosis and better treatment.
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http://dx.doi.org/10.1016/j.wneu.2018.08.125DOI Listing
December 2018

Molecular diagnostic testing of diffuse gliomas in the real-life setting: A practical approach.

Clin Neuropathol 2018 Jul/Aug;37(4):166-177

Typing of diffuse gliomas according to the WHO 2016 Classification of Tumors of the Central Nervous System is based on the integration of histology with molecular biomarkers. However, the choice of appropriate methods for molecular analysis and criteria for interpretation of test results is left to each diagnostic laboratory. In the present study, we tested the applicability of combined immunohistochemistry, direct sequencing, and multiplex ligation-dependent probe amplification (MLPA) for diagnostic assessment of IDH1/2 mutation status, chromosome 1p/19q status, and TERT promoter mutations. To this end, we analyzed a consecutive series of 165 patients with diffuse low- and high-grade gliomas (WHO grade II and III) from three Austrian centers in which tissue specimens were routinely processed. We could reliably detect IDH1/2 mutations by combining immunohistochemistry, direct sequencing, and MLPA analysis. MLPA analysis also allowed reliable detection of combined whole chromosomal arm 1p/19q codeletion when using carefully selected criteria providing an optimal balance between sensitivity and specificity. Direct sequencing proved to be suitable for identification of TERT promoter mutations, although its analytical performance remains to be assessed. To conclude, we propose a practicable combination of methods and criteria which allow reliable molecular diagnostic testing of diffuse gliomas in the real-life setting.
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http://dx.doi.org/10.5414/NP301110DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6102559PMC
November 2018

Bioimaging and surgery of brain tumors.

Handb Clin Neurol 2017 ;145:535-545

Department of Neurosurgery, Medical University of Vienna, Vienna, Austria; Central Nervous System Tumors Unit, Comprehensive Cancer Center, Medical University of Vienna, Vienna, Austria.

Bioimaging of brain tumors using nuclear medicine techniques complements computed tomography (CT) and magnetic resonance imaging (MRI), thus allowing more accurate diagnosis in clinically ambiguous situations. Special tracers for positron emission tomography (PET) have been developed which allow monitoring and planning of therapy. PET data may provide also presurgical evidence with regard to the presence of clinically relevant molecular brain tumor biomarkers. Combined PET/CT and PET/MR hybrid imaging systems will further enhance bioimaging-based brain tumor analysis. The main aim of brain tumor surgery is maximal safe tumor resection with preservation of neurologic functions, and to relieve tumor-related symptoms. In deep-seated unresectable tumors, diagnostic biopsy may be the main surgical goal. Special pre- and intraoperative techniques and approaches, including multidisciplinary team approaches, have been developed to optimize these surgical goals. Differences in spectrum, biology, and clinical presentation of brain tumors in the pediatric patient population demand special surgical expertise to warrant optimal postoperative patient outcome.
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http://dx.doi.org/10.1016/B978-0-12-802395-2.00033-XDOI Listing
January 2018

Clinical neuropathology of brain tumors.

Handb Clin Neurol 2017 ;145:477-534

Institute of Neurology, Medical University of Vienna, Vienna, Austria; Comprehensive Cancer Center - Central Nervous System Tumors Unit (CCC-CNS), Medical University of Vienna, Vienna, Austria. Electronic address:

Brain tumor typing is a major task in the daily practice of clinical neuropathologists. For more than 100 years, brain tumors have been classified on the basis of a histogenetic concept, with the definition of more than 120 brain tumor entities over time. In the past decades, biomedical research on brain tumors has led to the identification of clinically meaningful diagnostic, prognostic, and predictive molecular markers. Taking this progress into account, the 2016 update of the World Health Organization classification of tumors of the central nervous system has incorporated for the first time molecular markers for definition of brain tumor entities. This development has resulted in integrated diagnostics on the basis of histologic and molecular characteristics. This chapter summarizes essential features of brain tumors in the light of integrated diagnostics. To provide a comprehensive view on the individual tumor entities, we included crucial epidemiologic, clinical, and neuroradiologic aspects as well. In addition we illustrate neuroimaging and histologic characteristics of the various tumor types. In this way we aim to provide concise up-to-date insight into the nature and classification of brain tumors.
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http://dx.doi.org/10.1016/B978-0-12-802395-2.00032-8DOI Listing
January 2018

Urinary F-Isoprostane Concentration as a Poor Prognostic Factor After Subarachnoid Hemorrhage.

World Neurosurg 2017 Nov 3;107:185-193. Epub 2017 Aug 3.

Department of Neurosurgery and Neurooncology, Medical University of Lodz, Barlicki University Hospital, Lodz, Poland.

Background: The role of isoprostanes in cerebral vasospasm (CVS) following aneurysmal subarachnoid hemorrhage (aSAH) is controversial. Recent studies have suggested that the level of isoprostanes in cerebrospinal fluid could play a role in outcomes of patients with aSAH. We measured concentration of urinary F-isoprostanes (F-IsoPs), which is simple and noninvasive.

Methods: A prospective analysis was performed of clinical data and urine samples of 20 patients with aSAH who underwent microsurgical clipping of the aneurysmal neck between May 2016 and January 2017. The role of F-IsoPs as a CVS biomarker was analyzed with regard to clinical conditions of patients. Outcome was assessed at discharge and 1-month and 4-month follow-up using the Glasgow Outcome Scale and modified Rankin Scale.

Results: The concentration of urinary F-IsoPs was significantly greater in patients with aSAH than in healthy control subjects (P < 0.001). Additionally, increased F-IsoP levels on day 3 after aSAH were associated with development of CVS (P = 0.015) and worse neurologic performance after 1 month (P = 0.042) and 4 months (P = 0.027). The prognostic value of urinary F-IsoPs on day 3 in terms of CVS was found to be high (area under the curve 0.864, 95% confidence interval 0.691-1.000).

Conclusions: Urinary F-IsoPs may be used as a noninvasive prognostic biochemical marker in patients with aSAH. F-IsoP levels in urine may have significant implications in pathogenesis of CVS.
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http://dx.doi.org/10.1016/j.wneu.2017.07.145DOI Listing
November 2017

Validation of nuclear STAT6 immunostaining as a diagnostic marker of meningeal solitary fibrous tumor (SFT)/hemangiopericytoma.

Clin Neuropathol 2017 Mar/Apr;36 (2017)(2):56-59

Introduction: NAB2-STAT6 gene fusion is a molecular characteristic of solitary fibrous tumors (SFT) and hemangiopericytoma, underscoring their definition as one diagnostic entity. NAB2-STAT6 fusion is associated with nuclear relocation of STAT6 protein that can be detected by immunohistochemistry. We evaluated the diagnostic value of STAT6 expression in meningeal tumors.

Methods: 77 meningeal tumors (17/77 (22.0%) SFT/hemangiopericytoma, 11/77 meningothelial meningioma, 10/77 atypical meningioma 8/77 chordoid meningioma, 9/77 fibroblastic meningioma, 10/77 transitional meningioma, 3/77 rhabdoid meningioma and 9/77 anaplastic meningioma) were included. STAT6 immunohistochemistry was performed on FFPE specimens using a fully automated slide-staining system and anti-STAT6 antibody SC-20:sc621. Two independent observers analyzed all specimens blinded to histological diagnoses, and a third observer was consulted in case of discordancy.

Results: STAT6 immunohistochemistry yielded an exclusively nuclear immunostaining signal. 16/17 (94%) SFT/hemangiopericytoma specimens presented with clear-cut, wide-spread, and moderate to strong staining in tumor cell nuclei and were rated as STAT6-positive. In only 1 SFT case with weak and focal nuclear STAT6 immunostaining signal, STAT6 expression was rated discordant (observer 1: STAT6-negative, observers 2 and 3: STAT6-positive). All non-SFT/hemangiopericytoma cases were unanimously rated as STAT6-negative. In 76/77 (98.7%) cases the evaluation of STAT6 immunostaining results was in agreement among observers.

Conclusion: STAT6 immunohistochemistry is a robust method to verify diagnosis of SFT/hemangiopericytoma and should therefore be included in the diagnostic work-up of meningeal tumors. In singular cases, weak and focal STAT6 expression may lead to false-negative evaluation and may prompt further molecular work-up.
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http://dx.doi.org/10.5414/NP300993DOI Listing
March 2017

BRAF inhibitors in BRAF-V600 mutated primary neuroepithelial brain tumors.

Expert Opin Investig Drugs 2016 4;25(1):7-14. Epub 2015 Nov 4.

b Comprehensive Cancer Center Vienna, CNS Unit , Medical University of Vienna , Vienna , Austria.

Introduction: Primary neuroepithelial brain tumors encompass a wide variety of glial and glioneuronal neoplasms. Malignant tumors, tumors located in surgically inaccessible locations (e.g., eloquent brain areas, deep structures, brain stem) and recurrent or progressive tumors pose considerable treatment challenges and are candidates for novel therapeutics based on molecular insights. Small kinase inhibitors of v-RAF murine sarcoma viral oncogene homologue B1 (BRAF) have shown considerable antineoplastic activity in some tumor types harboring activating BRAF-V600 mutations (e.g., melanoma) and promising data are emerging on BRAF inhibitor therapy of mutation-bearing primary brain tumors.

Areas Covered: This review summarizes the available data on BRAF-V600 point mutations and the antineoplastic activity and toxicity profiles of BRAF inhibitors in neuroepithelial brain tumors including diffuse gliomas (glioblastomas, astrocytomas, oligodendrogliomas), pilocytic astrocytomas, pleomorphic xanthoastrocytomas and gangliogliomas.

Expert Opinion: Activating BRAF-V600 mutations are recurrently found in several glial and glioneuronal brain tumors and the available data indicate that BRAF inhibitors are active and well-tolerated in such tumors. Thus, BRAF inhibitors represent a novel and promising therapeutic opportunity that may alter the disease course of molecularly selected CNS neoplasms in a clinically meaningful way. However, so far the evidence is anecdotal and prospective clinical studies should be conducted.
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http://dx.doi.org/10.1517/13543784.2016.1110143DOI Listing
September 2016

KINFix--A formalin-free non-commercial fixative optimized for histological, immunohistochemical and molecular analyses of neurosurgical tissue specimens.

Clin Neuropathol 2016 Jan-Feb;35(1):3-12

An optimal fixative should ideally combine the advantages of formalin fixation and freezing, allowing for good preservation of histology and molecular components, easy handling and storage, lack of toxicity, and low costs. Most of these criteria are fulfilled by ethanol-based solutions, and due to our good experience with the commercial RCL2 fixative, reflected by our published single-center trial, we initiated a multicenter ring trial. However, during its course, RCL2 was discontinued on the market. Therefore, we created our own agent, KINFix, composed of the same main constituents as RCL2, and employed it in our laboratory with similar results. Here we present our evaluation of the three fixatives formalin, RCL2, and KINFix from the perspective of histopathology as well as nucleic acid and protein analyses in comparison to fresh frozen tissues together with the multicenter ring trial data for RCL2. We observe that RCL2 and KINFix offer comparable histomorphology and superior template for molecular analyses than formalin. Moreover, KINFix as freely available fixative might overcome some of the difficulties related to the commercial agents. Therefore, we conclude that KINFix might be an attractive complement to formalin in tissue processing and advocate its use in neuropathological practice.
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http://dx.doi.org/10.5414/NP300907DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4766796PMC
September 2016

Prognostic role of tumour-infiltrating inflammatory cells in brain tumours: literature review.

Curr Opin Neurol 2015 Dec;28(6):647-58

aInstitute of Neurology, Medical University of Vienna, Vienna bDepartment of Molecular Pathology and Neuropathology, Medical University of Lodz, Lodz cDepartment of Medicine I, Medical University of Vienna, Vienna, Austria.

Purpose Of Review: Both primary and metastatic brain tumours pose a significant and unmet clinical need. Immune cells infiltrating the tumour have been shown to affect the clinical course of various extracranial tumour types, but there is little knowledge on the role of tumour-infiltrating immune cells in brain tumours. Thus, the aim of this review was to recapitulate the reports on immune infiltrates in brain tumours and their prognostic significance.

Recent Findings: Immune infiltrates composed of various lymphocyte subsets and microglia/macrophages are frequently observed in brain tumours; however, their density and prognostic role seem to differ between tumour types. Central nervous system (CNS) metastases, particularly of melanoma, lung cancer and renal cell cancer, commonly show high amounts of tumour-infiltrating lymphocytes and tumour-infiltrating lymphocytes density strongly correlate with patient's overall survival times in patients with CNS metastases. In gliomas and primary CNS lymphomas, some studies also suggest a prognostic role of immune cell infiltration; however, methodological issues such as low sample size and retrospective study designs with heterogeneous patient populations preclude definite conclusions. Meningiomas typically harbour inflammatory infiltrates, but their correlation with the clinical course is unclear because of the lack of studies correlating immune cell infiltrates with outcome parameters.

Summary: The available literature suggests a relevant role of immune infiltrates in the clinical course of some brain tumour types; however, further studies are required to better understand the interaction of the immune system and CNS neoplasms and to explore therapeutic opportunities with immunotherapies such as vaccines or immune checkpoint modulators.
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http://dx.doi.org/10.1097/WCO.0000000000000251DOI Listing
December 2015

Clinical Neuropathology practice guide 5-2015: MGMT methylation pyrosequencing in glioblastoma: unresolved issues and open questions.

Clin Neuropathol 2015 Sep-Oct;34(5):250-7

Institute of Neurology, Medical University of Vienna, Vienna, Austria, Department of Molecular Pathology and Neuropathology, Medical University of Lodz, Lodz, Poland, Department of Medicine I, Comprehensive Cancer Center-CNS Tumours Unit (CCC-CNS), and Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria.

O6-methylguanine-methyltransferase (MGMT) promoter methylation status has prognostic and, in the subpopulation of elderly patients, predictive value in newly diagnosed glioblastoma. Therefore, knowledge of the MGMT promoter methylation status is important for clinical decision-making. So far, MGMT testing has been limited by the lack of a robust test with sufficiently high analytical performance. Recently, one of several available pyrosequencing protocols has been shown to be an accurate and robust method for MGMT testing in an intra- and interlaboratory ring trial. However, some uncertainties remain with regard to methodological issues, cut-off definitions, and optimal use in the clinical setting. In this article, we highlight and discuss several of these open questions. The main unresolved issues are the definition of the most relevant CpG sites to analyze for clinical purposes and the determination of a cut-off value for dichotomization of quantitative MGMT pyrosequencing results into "MGMT methylated" and "MGMT unmethylated" patient subgroups as a basis for further treatment decisions.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4542181PMC
http://dx.doi.org/10.5414/np300904DOI Listing
July 2016

PIN3 duplication may be partially responsible for TP53 haploinsufficiency.

BMC Cancer 2014 Sep 15;14:669. Epub 2014 Sep 15.

Department of Tumor Biology, Medical University of Lodz, Zeligowskiego 7/9, 90-752, Lodz, Poland.

Background: Previously we have suggested that cancer cells develop a mechanism(s) which allows for either: silencing of the wild-type TP53 transcription, degradation of the wild-type TP53 mRNA, or selective overproduction of the mutated TP53 mRNA, which is the subject of this article. Sequencing of TP53 on the respective cDNA and DNA templates from tumor samples were found to give discordant results. DNA analysis showed a pattern of heterozygous mutations, whereas the analysis of cDNA demonstrated the mutated template only. We hypothesized that different TP53 gene expression levels of each allele may be caused by the polymorphism within intron 3 (PIN3). The aim of this study was to test if one of the polymorphic variants of PIN3 (A1 or A2) in the heterozygotes is associated with a higher TP53 expression, and therefore, responsible for the haploinsufficiency phenomenon.

Methods: 250 tumor samples were tested. To analyze the involvement of PIN3 polymorphic variant (A1 or A2) on TP53 mRNA expression regulation, bacterial subcloning combined with sequencing analyses, dual luciferase reporter assays and bioinformatic analysis were performed.

Results: Haplotype analysis showed the predominance of the mutated template during the cDNA sequencing in all samples showing a heterozygous TP53 mutation and PIN3 heterozygosity. Out of 30 samples (from the total of 250 tested samples) which carried TP53 mutations and had a bias in allelic expression 6 were heterozygous for the A1/A2 polymorphism, and all 6 (p = 0.04) samples carried the mutation within the PIN3 longer allele (A2). Reporter assays revealed higher luciferase activity in cells transfected with the plasmid containing A2 construct than A1 and control. A2/A1 ratio ranged from 1.16 for AD293 cell line (p = 0.019) to 1.59 for SW962 cell line (p = 0.0019). Moreover, bioinformatic analyses showed that PIN3 duplication stabilized secondary DNA structures - G-quadruplexes.

Conclusion: TP53 alleles are not equivalent for their impact on the regulation of expression of TP53 mRNA. Therefore, in PIN3-heterozygous cases a single TP53 mutation of the longer allele might sufficiently destabilize its function. Secondary DNA structures such as quadruplexes can also play a role in PIN3-dependent TP53 haploinsufficiency.
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http://dx.doi.org/10.1186/1471-2407-14-669DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4176858PMC
September 2014

Different mutational characteristics of TSG in cell lines and surgical specimens.

Tumour Biol 2014 Nov 14;35(11):11311-8. Epub 2014 Aug 14.

Department of Tumor Biology, Medical University of Lodz, Lodz, Poland,

One of the most crucial concerns of cancer research pertains to the differences between the neoplastic cells in tumor specimens in vivo and their counterparts in cell lines. The huge amount of results deposited in cancer genetic databases allows to address this issue from a wider perspective. Our analysis of the Sanger Institute Catalog Of Somatic Mutations In Cancer (COSMIC) database v61 showed a lower percentage of homozygous mutations in a group of tumor suppressor genes in surgical samples (in vivo) in comparison to their frequency in cell lines (in vitro). Similarly, the mutations resulting in the lack of protein (e.g., nonsense mutations or whole gene deletions) of several tumor suppressor genes (TSGs) were more frequently observed in vitro than in vivo. In this article, we suggest two potential explanations of these data. Firstly, TSG heterozygous mutations resulting in the modified protein (e.g., missense mutations) may be gradually (when the specific molecular context is achieved) changed to homozygous mutations resulting in the lack of protein during carcinogenesis. Secondly, among different independent pathways of tumorigenesis, those leading to homozygous nonsense mutations are characteristic for cells which are more efficiently stabilized in vitro. To conclude, these observations may be interesting for researchers working with cell line in vitro models illustrating the extent to which they reflect the tumors in vivo.
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http://dx.doi.org/10.1007/s13277-014-2444-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4244698PMC
November 2014

Spontaneous in vitro senescence of glioma cells confirmed by an antibody against IDH1R132H.

Anticancer Res 2014 Jun;34(6):2859-67

Department of Tumor Biology, Medical University of Lodz, Lodz, Poland.

Background: We have recently suggested that glioblastoma cells become spontaneously senescent in cell culture conditions. The antibody specific against IDH1(R132H) offers the perfect opportunity to verify this hypothesis.

Materials And Methods: We analyzed the features of senescence in 8 glioma cell cultures showing the IDH1(R132H) mutation based on combination of immunocytochemistry, enzymo-cytochemistry, BrdU incorporation assay and real-time microscopic observation.

Results: We report that glioma cells showing the IDH1(R132H) mutation become rapidly and spontaneously senescent in vitro. Senescence was observed in both classical and novel serum-free cell culture conditions. Importantly, the senescent IDH1(R132H)-positive cells showed the expression of stemness marker (SOX2).

Conclusion: In vitro senescence appeared to be the main reason of the difficulties in any kind culturing of glioma cells. 3D cell cultures prolonged the survival and in vitro proliferation of neoplastic IDH1(R132H)-positive cells, however, did not enhance the stabilization efficiency. Senescence of glioma cells is spontaneously triggered in vitro, which offers the opportunity of potential new therapeutic strategies based on this phenomenon.
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June 2014

The failure in the stabilization of glioblastoma-derived cell lines: spontaneous in vitro senescence as the main culprit.

PLoS One 2014 30;9(1):e87136. Epub 2014 Jan 30.

Department of Tumor Biology, Medical University of Lodz, Lodz, Poland.

Cell line analysis is an important element of cancer research. Despite the progress in glioblastoma cell culturing, the cells isolated from the majority of specimens cannot be propagated infinitely in vitro. The aim of this study was to identify the processes responsible for the stabilization failure. Therefore, we analyzed 56 primary GB cultures, 7 of which were stabilized. Our results indicate that senescence is primarily responsible for the glioblastoma cell line stabilization failure, while mitotic catastrophe and apoptosis play a minor role. Moreover, a new technical approach allowed for a more profound analysis of the senescent cells in primary cultures, including the distinction between tumor and normal cells. In addition, we observed that glioblastoma cells in primary cultures have a varied potential to undergo spontaneous in vitro senescence, which is often higher than that of the normal cells infiltrating the tumor. Thus, this is the first report of GB cells in primary cell cultures (including both monolayer and spheroid conditions) rapidly and spontaneously becoming senescent. Intriguingly, our data also suggest that nearly half of GB cell lines have a combination of TP53 mutation and CDKN2A homozygous deletion, which are considered as mutually exclusive in glioblastoma. Moreover, recognition of the mechanisms of senescence and mitotic catastrophe in glioblastoma cells may be a step towards a potential new therapeutic approach.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0087136PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3910690PMC
December 2014

EGFRvIII--a stable target for anti-EGFRvIII therapy.

Anticancer Res 2013 Dec;33(12):5343-8

Department of Tumor Biology, Medical University of Lodz, Zeligowskiego 7/9, 90-752 Lodz, Poland.

Background: Epidermal growth factor receptor (EGFR) gene alterations play important roles in pathogenesis of glioblastoma. Antibodies against EGFRvIII have been recently developed. Their efficacy depends on numerous factors, including the co-existence of EGFRvIII with other genetic alterations, and especially with point mutations of EGFR.

Materials And Methods: We examined 91 patients diagnosed with glioblastoma in order to determine the prevalence and mutual relationships between EGFR alterations. Real-time polymerase chain reaction (real-time PCR), fluorescent in situ hybridization (FISH), and sequencing were used to analyze prevalence of the amplification of EGFR gene, polysomy of chromosome 7, EGFRvIII mutation, and point mutations in exons 7-8 and 15 of EGFR.

Results: We revealed that all these alterations can occur independently from each other. Nevertheless, the co-existence of EGFRvIII mutation and excessive copies of EGFR gene was observed in most cases (10/14). Similarly, the point mutations in exons 7-8 and 15 co-existed with an excessive number of EGFR copies in nearly all cases.

Conclusion: EGFRvIII is a reliable and stable target for anti-EGFRvIII therapy.
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December 2013

Screening for EGFR amplifications with a novel method and their significance for the outcome of glioblastoma patients.

PLoS One 2013 6;8(6):e65444. Epub 2013 Jun 6.

Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Lodz, Lodz, Poland.

Glioblastoma is a highly aggressive tumour of the central nervous system, characterised by poor prognosis irrespective of the applied treatment. The aim of our study was to analyse whether the molecular markers of glioblastoma (i.e. TP53 and IDH1 mutations, CDKN2A deletion, EGFR amplification, chromosome 7 polysomy and EGFRvIII expression) could be associated with distinct prognosis and/or response to the therapy. Moreover, we describe a method which allows for a reliable, as well as time- and cost-effective, screening for EGFR amplification and chromosome 7 polysomy with quantitative Real-Time PCR at DNA level. In the clinical data, only the patient's age had prognostic significance (continuous: HR = 1.04; p<0.01). At the molecular level, EGFRvIII expression was associated with a better prognosis (HR = 0.37; p = 0.04). Intriguingly, EGFR amplification was associated with a worse outcome in younger patients (HR = 3.75; p<0.01) and in patients treated with radiotherapy (HR = 2.71; p = 0.03). We did not observe any difference between the patients with the amplification treated with radiotherapy and the patients without such a treatment. Next, EGFR amplification was related to a better prognosis in combination with the homozygous CDKN2A deletion (HR = 0.12; p = 0.01), but to a poorer prognosis in combination with chromosome 7 polysomy (HR = 14.88; p = 0.01). Importantly, the results emphasise the necessity to distinguish both mechanisms of the increased EGFR gene copy number (amplification and polysomy). To conclude, although the data presented here require validation in different groups of patients, they strongly advocate the consideration of the patient's tumour molecular characteristics in the selection of the therapy.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0065444PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3675194PMC
January 2014

Reduced expression of ELAVL4 in male meningioma patients.

Brain Tumor Pathol 2013 Jul 11;30(3):160-6. Epub 2012 Sep 11.

Department of Molecular Pathology and Neuropathology, Medical University of Lodz, Czechoslowacka 8/10, 92-216 Lodz, Poland.

Meningioma is a frequently occurring tumor of the central nervous system. Among many genetic alternations, the loss of the short arm of chromosome 1 is the second most frequent chromosomal abnormality observed in these tumors. Here, we focused on the previously described and well-established minimal deletion regions of chromosome 1. In accordance with the Knudson suppressor theory, we designed an analysis of putative suppressor genes localized in the described minimal deletion regions. The purpose was to determine the molecular background of the gender-specific occurrence of meningiomas. A total of 149 samples were examined for loss of heterozygosity (LOH). In addition, 57 tumor samples were analyzed using real-time polymerase chain reaction. We examined the association between the expression of selected genes and patient age, gender, tumor grade and presence of 1p loss. Furthermore, we performed an analysis of the most stable internal control for real-time analysis in meningiomas. LOH analysis revealed gender-specific discrepancies in the frequency of 1p aberrations. Moreover, statistical correlation between the gene expression level and gender was significant for the ELAVL4 gene as we found it to be lower in males than in females. We conclude that meningiomas present different features depending on patient gender. We suggest that ELAVL4 can be involved in the pathogenesis of meningiomas in male patients.
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http://dx.doi.org/10.1007/s10014-012-0117-xDOI Listing
July 2013

Limited importance of the dominant-negative effect of TP53 missense mutations.

BMC Cancer 2011 Jun 13;11:243. Epub 2011 Jun 13.

Department of Molecular Pathology and Neuropathology, Chair of Oncology, Medical University of Lodz, Czechoslowacka 8/10, 92-216 Lodz, Poland.

Background: Heterozygosity of TP53 missense mutations is related to the phenomenon of the dominant-negative effect (DNE). To estimate the importance of the DNE of TP53 mutations, we analysed the percentage of cancer cases showing a single heterozygous mutation of TP53 and searched for a cell line with a single heterozygous mutation of this gene. This approach was based on the knowledge that genes with evident DNE, such as EGFR and IDH1, represent nearly 100% of single heterozygous mutations in tumour specimens and cell lines.

Methods: Genetic analyses (LOH and sequencing) performed for early and late passages of several cell lines originally described as showing single heterozygous TP53 mutations (H-318, G-16, PF-382, MOLT-13, ST-486 and LS-123). Statistical analysis of IARC TP53 and SANGER databases. Genetic analyses of N-RAS, FBXW7, PTEN and STR markers to test cross-contamination and cell line identity. Cell cloning, fluorescence-activated cell sorting and SSCP performed for the PF-382 cell line.

Results: A database study revealed TP53 single heterozygous mutations in 35% of in vivo (surgical and biopsy) samples and only 10% of cultured cells (in vitro), although those numbers appeared to be overestimated. We deem that published in vivo TP53 mutation analyses are not as rigorous as studies in vitro, and we did not find any cell line showing a stable, single heterozygous mutation. G16, PF-382 and MOLT-13 cells harboured single heterozygous mutations temporarily. ST-486, H-318 and LS-123 cell lines were misclassified. Specific mutations, such as R175H, R273H, R273L or R273P, which are reported in the literature to exert a DNE, showed the lowest percentage of single heterozygous mutations in vitro (about 5%).

Conclusion: We suggest that the currently reported percentage of TP53 single heterozygous mutations in tumour samples and cancer cell lines is overestimated. Thus, the magnitude of the DNE of TP53 mutations is questionable. This scepticism is supported by database investigations showing that retention of the wild-type allele occurs with the same frequency as either nonsense or missense TP53 mutations.
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http://dx.doi.org/10.1186/1471-2407-11-243DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3129589PMC
June 2011