Renal oncocytosis is characterized by the presence of multiple tumors with oncocytic features, often associated with small clusters of tubule-like structures with oncocytic change. The morphologic features of the oncocytic nodules encompass a spectrum of appearances, with patterns typical of renal oncocytoma or classic chromophobe renal cell carcinoma, as well as 'hybrid' tumors with features resembling both oncocytoma and chromophobe renal cell carcinoma. We utilized interphase cytogenetic methods to study 11 tumors from the kidneys of a 45-year-old woman. The tumors included morphologically classical oncocytomas and 'hybrid' tumors with features reminiscent of chromophobe carcinoma. The kidneys also showed foci of oncocytic change in renal tubules. Fluorescence in situ hybridization was performed with centromeric probes for chromosomes 1, 2, 6, 10, and 17 in each of the 11 tumors to determine whether or not there were losses of the chromosomes that are most frequently lost in chromophobe renal cell carcinomas. Neoplastic nuclei from each tumor were evaluated for the number of hybridization signals and scored according to the percentage of nuclei with one, two, and three or more signals. The normal renal parenchyma surrounding the tumors was used as control tissue. All 11 tumors from this patient with renal oncocytosis showed no loss of any of the chromosomes 1, 2, 6, 10, or 17, a pattern identical to that found in normal control tissues. These observations weigh against the concept that hybrid tumors of oncocytosis are closely related to chromophobe renal cell carcinoma.

<p>Inappropriate expression of EVI1 (ecotropic virus integration-1), in particular splice form EVI1-1D, through chromosome 3q26 lesions or other mechanisms has been implicated in the development of high-risk acute myeloid leukemia (AML). To validate the clinical relevance of EVI1-1D, as well as of the other EVI1 splice forms and the related MDS1/EVI1 (ME) gene, real-time quantitative polymerase chain reaction was performed in 534 untreated adults with de novo AML. EVI1-1D was highly expressed in 6% of cases (n = 32), whereas 7.8% were EVI1(+) (n = 41) when all splice variants were taken into account. High EVI1 predicted a distinctly worse event-free survival (HR = 1.9; P = .002) and disease-free survival (HR = 2.1, P = .006) following multivariate analysis. Importantly, we distinguished a subset of EVI1(+) cases that lacked expression of ME (EVI1(+)ME(-); n = 17) from cases that were ME(+) (EVI1(+)ME(+); n = 24). The atypical EVI1(+)ME(-) expression pattern exhibited cytogenetically detectable chromosomal 3q26 breakpoints in 8 cases. Fluorescence in situ hybridization revealed 7 more EVI1(+)ME(-) cases that carried cryptic 3q26 breakpoints, which were not found in the EVI1(+)ME(+) group. EVI1(+)ME(-) expression predicts an extremely poor prognosis distinguishable from the general EVI1(+) AML patients (overall survival [OS]: P</p>

<p>The acute myeloid leukemia (AML) subtype M4Eo occurs in 5% of all AML cases and is usually associated with either an inv(16)(p13.1q22) or a t(16;16)(p13.1;q22) chromosomal abnormality. At the molecular level, these abnormalities generate a CBFB-MYH11 fusion gene. Patients with this genetic alteration are usually assigned to a low-risk group and thus receive standard chemotherapy. AML-M4Eo is rarely found in infants. We describe clinical, conventional banding, and molecular cytogenetic data for a 12-month-old baby with AML-M4Eo and a chimeric CBFB-MYH11 fusion gene masked by a novel rearrangement between chromosomes 1 and 16. This rearrangement characterizes a new type of inv(16)(p13.1q22) masked by a chromosome translocation.</p>

Digital object identifier (DOI): 10.1016/j.cancergencyto.2007.12.014

<p>There is a steady search for procedure which could replace or at least reduce the frequency of the invasive cystoscopy in the surveillance of heterogeneous superficial transitional cell carcinoma (TCC) of the bladder. Recently, UroVysion FISH assay has been shown to provide with better sensitivity than the urine cytology except for the lowest stage pTa and grade I-II TCCs. Data indicate that this failure of the sensitive FISH might be due to mistargeting. Therefore, our aim was to elaborate a procedure enabling FISH analysis in phenotypically preselected urothelial cells, only. Cytokeratin 7 (CK-7) chromogenic immunolabeling was applied to various mixtures of negative and positive control cells as well as voided urine specimens. Cellular targets and CK-7 positive cells were identified by morphometric and pixel intensity indices using an automated microscope workstation. UroVysion FISH pattern was analyzed only in the subsequently relocalized CK-7 positive events. Automated phenotypical preselection of urothelial cells proved to have 97.3% sensitivity, 96.1% specificity, and 99.0% accuracy, whereas combined pheno- and genotyping revealed 93.3% sensitivity and 99.8% specificity, respectively. In clinical samples, the overall 20.4% FISH positivity gained by traditional target identification contrasted with the 55.6% positivity obtained by the combined method, by which the efficiency of identifying chromosomally aberrant cells proved to be two to threefold higher even in grade I lesions. FISH analysis of phenotypically preselected urothelial cells might represent a reliable asset in surveillance of low stage-low grade TCCs.</p>

Mazor, R., Korenstein-Ilan, A., Barbul, A., Eshet, Y., Shahadi, A., Jerby, E. and Korenstein, R. Increased Levels of Numerical Chromosome Aberrations after In Vitro Exposure of Human Peripheral Blood Lymphocytes to Radiofrequency Electromagnetic Fields for 72 Hours. Radiat. Res. 169, 28-37 (2008). We investigated the effects of 72 h in vitro exposure of 10 human lymphocyte samples to radiofrequency electromagnetic fields (800 MHz, continuous wave) on genomic instability. The lymphyocytes were exposed in a specially designed waveguide resonator at specific absorption rates (SARs) of 2.9 and 4.1 W/kg in a temperature range of 36-37 degrees C. The induced aneuploidy of chromosomes 1, 10, 11 and 17 was determined by interphase FISH using semi-automated image analysis. We observed increased levels of aneuploidy depending on the chromosome studied as well as on the level of exposure. In chromosomes 1 and 10, there was increased aneuploidy at the higher SAR, while for chromosomes 11 and 17, the increases were observed only for the lower SAR. Multisomy (chromosomal gains) appeared to be the primary contributor to the increased aneuploidy. The effect of temperature on the level of aneuploidy was examined over the range of 33.5-40 degrees C for 72 h with no statistically significant difference in the level of aneuploidy compared to 37 degrees C. These findings suggest the possible existence of an athermal effect of RF radiation that causes increased levels of aneuploidy. These results contribute to the assessment of potential health risks after continuous chronic exposure to RF radiation at SARs close to the current levels set by ICNIRP guidelines.

Recently, an influential sequencing study found that more than 1700 genes had non-silent mutations in either a breast or colorectal cancer, out of just 11 breast and 11 colorectal tumor samples. This is not surprising given the fact that genomic instability is the hallmark of cancer cells. The plethora of genomic alterations found in every carcinoma does not obey the ‘law of genotype–phenotype correlation’, since the same histological subtype of cancer harbors different gene mutations and chromosomal aberrations in every patient. In an attempt to make sense out of the observed genetic and chromosomal chaos in cancer, I propose a cascade model. According to this model, tissue regeneration depends on the proliferation and serial activation of stem cells. Replicative telomere erosion limits the proliferative life span of adult stem cells and results in the Hayflick limit (M1). However, local tissue exhaustion or old age might promote the activation of M1-deficient tissue stem cells. Extended proliferation of these cells leads to telomere-driven chromosomal instability and aneuploidy (abnormal balance of chromosomes and/or chromosome material). Several of the aforementioned steps have been already described in the literature. However, in contrast to common theories, it is proposed here that the genomic damage blocks the epigenetic differentiation switch. As a result of aneuploidy, differentiation-specific genes cannot be activated by modification of methylation patterns. Consequently, the phenotype of cancer tissue is largely determined by the epigenetic maturation arrest of tissue stem cells, which in addition enables a fraction of cancer cells to proliferate, invade and metastasize, as normal adult stem cells do. The new model combines genetic and epigenetic alterations of cancer cells in one causative cascade and offers an explanation for why identical histologic cancer types harbor a confusing variety of chromosomal and gene aberrations. The Viennese Cascade, as presented here, may end the debate on if and how ‘tumor-unspecific’ aneuploidy leads to cancer.

Digital object identifier (DOI): http://dx.doi.org/10.1016/j.mehy.2008.01.010

Recently, an influential sequencing study found that more than 1700 genes had non-silent mutations in either a breast or colorectal cancer, out of just 11 breast and 11 colorectal tumor samples. This is not surprising given the fact that genomic instability is the hallmark of cancer cells. The plethora of genomic alterations found in every carcinoma does not obey the 'law of genotype-phenotype correlation', since the same histological subtype of cancer harbors different gene mutations and chromosomal aberrations in every patient. In an attempt to make sense out of the observed genetic and chromosomal chaos in cancer, I propose a cascade model. According to this model, tissue regeneration depends on the proliferation and serial activation of stem cells. Replicative telomere erosion limits the proliferative life span of adult stem cells and results in the Hayflick limit (M1). However, local tissue exhaustion or old age might promote the activation of M1-deficient tissue stem cells. Extended proliferation of these cells leads to telomere-driven chromosomal instability and aneuploidy (abnormal balance of chromosomes and/or chromosome material). Several of the aforementioned steps have been already described in the literature. However, in contrast to common theories, it is proposed here that the genomic damage blocks the epigenetic differentiation switch. As a result of aneuploidy, differentiation-specific genes cannot be activated by modification of methylation patterns. Consequently, the phenotype of cancer tissue is largely determined by the epigenetic maturation arrest of tissue stem cells, which in addition enables a fraction of cancer cells to proliferate, invade and metastasize, as normal adult stem cells do. The new model combines genetic and epigenetic alterations of cancer cells in one causative cascade and offers an explanation for why identical histologic cancer types harbor a confusing variety of chromosomal and gene aberrations. The Viennese Cascade, as presented here, may end the debate on if and how 'tumor-unspecific' aneuploidy leads to cancer.

Food irradiation is the process of exposing food to ionising radiation in order to disinfect, sanitise, sterilise and preserve food or to provide insect disinfestation. Irradiated food should be adequately labelled according to international and national guidelines. In many countries, there are furthermore restrictions to the product-specific maximal dose that can be administered. Therefore, there is a need for methods that allow detection of irradiated food, as well as for methods that provide a reliable dose estimate. In recent years, the comet assay was proposed as a simple, rapid and inexpensive method to fulfil these goals, but further research is required to explore the full potential of this method. In this paper we describe the use of an automated image analysing system to measure DNA comets which allow the discrimination between irradiated and non-irradiated food as well as the set-up of standard dose-response curves, and hence a sufficiently accurate dose estimation.

In 1957/58 the British Government conducted a series of nuclear tests in the mid-Pacific codenamed Operation Grapple, which involved several naval vessels from Britain and New Zealand. Two New Zealand frigates with 551 personnel onboard were stationed at various distances between 20 and 150 nautical miles from ground zero. In the present study we applied the cytomolecular technique mFISH (multicolour fluorescent in situ hybridisation) to investigate a potential link between chromosome abnormalities and possible past radiation exposure in New Zealand nuclear test veterans who participated in Operation Grapple. Compared to age matched controls, the veterans showed significantly higher (P < 0.0001) frequencies of chromosomal abnormalities (275 translocations and 12 dicentrics in 9,360 cells vs. 96 translocations and 1 dicentric in 9,548 cells in the controls), in addition to a significant excess of CCRs (complex chromosomal rearrangements) in the veterans. A Kolmogorov-Smirnoff test showed that the distributions of translocations for the two groups were significantly different.

Background Variant translocations t(9;22) occur in 5 to 10% of newly diagnosed CMLs and additional genetic changes are present in 60–80% of patients in blast crisis (BC). Here, we report on a CML patient in blast crisis presenting with a four-way variant t(9;22) rearrangement involving the EVI1 locus. Methods Dual-colour Fluorescence In Situ Hybridisation was performed to unravel the different cytogenetic aberrations. Expression levels of EVI1 and BCR/ABL1 were investigated using real-time quantitative RT-PCR. Results In this paper we identified a patient with a complex 4-way t(3;9;17;22) which, in addition to BCR/ABL1 gene fusion, also resulted in EVI1 rearrangement and overexpression. Conclusion This report illustrates how a variant t(9;22) translocation can specifically target a second oncogene most likely contributing to the more aggressive phenotype of the disease. Molecular analysis of such variants is thus warranted to understand the phenotypic consequences and to open the way for combined molecular therapies in order to tackle the secondary oncogenic effect which is unresponsive to imatinib treatment.

Detecting balanced translocations using tissue sections plays an important diagnostic role in cases of hematological malignancies. Manual scoring is often problematic due to truncation and overlapping of nuclei. Reports have described automated analysis using primarily tile sampling. The aim of this study was to investigate an automated fluorescent in situ hybridization analysis method using grid sampling on tissue sections, and compare the performance of dual-fusion (DF) and break-apart (BA) probes in this setting. Ten follicular, 10 mantle cell lymphoma, and 10 translocation-negative samples were used to set the threshold of false positivity using IGH/CCND1, IGH/BCL-2 DF, and IGH BA probes. The cut-off distances of red and green signals to define fusion signals were 0.5, 1.0, and 1.2 mum for the IGH/CCND1, IGH/BCL-2 DF, and IGH BA probes, respectively. The mean false positivity of grid units was 5.3, 11.4, and 28.1%, respectively. Ten to 14 additional samples analyzed blindly and were correctly classified using each probe. Discriminating positive and negative samples using automated analysis and grid sampling was possible with each probe, although different definitions of fusion signals were required due to the different physical distances between the DNA probes. Using the DF probes resulted in lower false positivity, which was less affected by signal numbers per grid units.

OBJECTIVE: To determine the precision and accuracy of an automated cell counting system when applied to counting aneuploidies in sperm samples. DESIGN: Prospective pilot study. SETTING: Andrology clinic and research laboratory in a university teaching hospital. PATIENT(S): Ten anonymous sperm donors of known fertility and two patients seeking infertility treatment. INTERVENTION(S): Semen samples were processed for detection of aneuploidies for chromosomes 13, 18, 21, X, and Y with use of fluorescent in situ hybridization. The detection of chromosome aneuploidy was performed both by manual counting and by the use of an automated cell counting system with manual review of aneuploid sperm. MAIN OUTCOME MEASURE(S): Semen samples were judged for the percent aneuploidy for chromosomes 13, 18, 21, X, and Y when counted manually or with the use of the automated cell counting system and review by a technician. RESULT(S): The sperm aneuploidy rates determined by the automated cell counting system and careful review were comparable with those obtained by manual counting by a trained technician. CONCLUSION(S): These preliminary data demonstrate that automated cell counting devices may be useful in increasing productivity in aneuploidy detection in sperm and may become an alternative to the labor-intensive manual counting by technicians.

Severe male infertility has been shown to be associated with improper meiotic recombination and elevated sperm chromosome aneuploidy. Elevated sperm aneuploidy increases the risk of embryo lethality or fetal anomalies. Although difficulties in interpreting aneuploidy data still exist, advances in fluorescent in situ hybridization (FISH) technology have facilitated the study of sperm from patients with severe spermatogenesis defects, which has demonstrated the prudence of evaluating sperm chromosome aneuploidy in men with severe male factor infertility, such as nonobstructive azoospermia or severe ultrastructure defects, especially in cases of previous repeated in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) failure. Testing is also advisable in men with chromosome translocations and unexplained recurrent pregnancy loss, and it may be beneficial in patients with unexplained, repeated IVF failure. Automated FISH imaging and analysis technology is now available and is beneficial in reducing technician time analyzing sperm aneuploidy. Emerging technologies, such comparative genomic hybridization, may be beneficial in further improving the quality of data derived from aneuploidy analysis and reducing the cost of the assay.

<p>BACKGROUND: The use of human embryonic stem cells (hESCs) in research is increasing and hESCs hold the promise for many biological, clinical and toxicological studies. Human ESCs are expected to be chromosomally stable since karyotypic changes represent a pitfall for potential future applications. Recently, several studies have analysed the genomic stability of several hESC lines maintained after prolonged in vitro culture but controversial data has been reported. Here, we prompted to compare the chromosomal stability of three hESC lines maintained in the same laboratory using identical culture conditions and passaging methods. RESULTS: Molecular cytogenetic analyses performed in three different hESC lines maintained in parallel in identical culture conditions revealed significant differences among them in regard to their chromosomal integrity. In feeders, the HS181, SHEF-1 and SHEF-3 hESC lines were chromosomally stable up to 185 passages using either mechanical or enzymatic dissection methods. Despite the three hESC lines were maintained under identical conditions, each hESC line behaved differently upon being transferred to a feeder-free culture system. The two younger hESC lines, HS181 (71 passages) and SHEF-3 (51 passages) became chromosomally unstable shortly after being cultured in feeder-free conditions. The HS181 line gained a chromosome 12 by passage 17 and a marker by passage 21, characterized as a gain of chromosome 20 by SKY. Importantly, the mosaicism for trisomy 12 gradually increased up to 89% by passage 30, suggesting that this karyotypic abnormality provides a selective advantage. Similarly, the SHEF-3 line also acquired a trisomy of chromosome 14 as early as passage 10. However, this karyotypic aberration did not confer selective advantage to the genetically abnormal cells within the bulk culture and the level of mosaicism for the trisomy 14 remained overtime between 15%-36%. Strikingly, however, a much older hESC line, SHEF-1, which was maintained for 185 passages in feeders did not undergo any numerical or structural chromosomal change after 30 passages in feeder-free culture and over 215 passages in total. CONCLUSION: These results support the concept that feeder-free conditions may partially contribute to hESC chromosomal changes but also confirm the hypothesis that regardless of the culture conditions, culture duration or splitting methods, some hESC lines are inherently more prone than others to karyotypic instability.</p>

ABSTRACT: Malignant melanomas are characterized by increased karyotypic complexity, extended aneuploidy and heteroploidy. We report a melanoma metastasis to the peritoneal cavity with an exceptionally stable, abnormal pseudodiploid karyotype as verified by G-Banding, subtelomeric, centromeric and quantitative Fluorescence in Situ Hybridization (FISH). Interestingly this tumor had no detectable telomerase activity as indicated by the Telomere Repeat Amplification Protocol. Telomeric Flow-FISH and quantitative telomeric FISH on mitotic preparations showed that malignant cells had relatively short telomeres. Microsatellite instability was ruled out by the allelic pattern of two major mononucleotide repeats. Our data suggest that a combination of melanoma specific genomic imbalances were sufficient and enough for this fatal tumor progression, that was not accompanied by genomic instability, telomerase activity, or the engagement of the alternative recombinatorial telomere lengthening pathway.

The American Society of Clinical Oncologists and College of American Pathologists have recently released new guidelines for laboratory testing of HER2 status in breast cancer, which require high levels (95%) of concordance between immunohistochemistry positive (3+) and fluorescence in situ hybridization-amplified cases, and between immunohistochemistry negative (0/1+) and fluorescence in situ hybridization-nonamplified cases; these required levels of concordance are significantly higher than those found in most published studies. We tested the hypothesis that a modification of the HER2 immunohistochemistry scoring system could significantly improve immunohistochemistry and fluorescence in situ hybridization concordance. A total of 6604 breast cancer specimens were evaluated for HER2 status by both immunohistochemistry and fluorescence in situ hybridization using standard methodologies. Results were compared when the standard immunohistochemistry scoring system was replaced by a normalized scoring system in which the HER2 score was derived by subtracting the score on the non-neoplastic breast epithelium from that on the tumor cells. Among the 6604 tumors, using a non-normalized immunohistochemistry scoring system, 267/872 (30.6%) of the immunohistochemistry 3+ cases proved to be fluorescence in situ hybridization nonamplified, whereas using the normalized scoring system only 30/562 (5.3%) of immunohistochemistry 3+ cases proved to be 'false positive'. The concordance rate between immunohistochemistry 3+ and fluorescence in situ hybridization-amplified cases using the normalized scoring method was 94.7%, whereas the concordance using the non-normalized method was only 69.4%. Extremely high concordance between immunohistochemistry and fluorescence in situ hybridization assessment of HER2 status in breast cancer is achievable, but to attain this high level of concordance, modification of the FDA-approved immunohistochemistry scoring system is required.

BACKGROUND: HER2 gene amplification and/or protein overexpression in breast cancer is associated with a poor prognosis and predicts response to anti-HER2 therapy. We examine the natural history of breast cancers in relationship to increased HER2 copy numbers in a large population-based study. PATIENTS AND METHODS: HER2 status was measured by fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) in approximately 1,400 breast cancer cases with greater than 15 years of follow-up. Protein expression was evaluated with two different commercially-available antibodies. RESULTS: We looked for subgroups of breast cancer with different clinical outcomes, based on HER2 FISH amplification ratio. The current HER2 ratio cut point for classifying HER2 positive and negative cases is 2.2. However, we found an increased risk of disease-specific death associated with FISH ratios of >1.5. An 'intermediate' group of cases with HER2 ratios between 1.5 and 2.2 was found to have a significantly better outcome than the conventional 'amplified' group (HER2 ratio >2.2) but a significantly worse outcome than groups with FISH ratios less than 1.5. CONCLUSION: Breast cancers with increased HER2 copy numbers (low level HER2 amplification), below the currently accepted positive threshold ratio of 2.2, showed a distinct, intermediate outcome when compared to HER2 unamplified tumors and tumors with HER2 ratios greater than 2.2. These findings suggest that a new cut point to determine HER2 positivity, at a ratio of 1.5 (well below the current recommended cut point of 2.2), should be evaluated.

<p>We aimed to directly align a chromosomal CGH (cCGH) pattern with the gene mapping data by taking advantage of the clustering of the GGCC motif at certain positions in the human genome. The alignment of chromosomal with sequence data was achieved by superimposition of (i) the fluorescence intensity of the sequence specific fluorochrome, Chromomycin A3 (CMA3), (ii) the cCGH fluorescence intensity profile of individual chromosomes and (iii) the GGCC density profile extracted from the Ensembl genome sequence database. The superimposition of these three pieces of information allowed us to precisely localize regions of amplification in the neuroblastoma cell line STA-NB-15. Two prominent cCGH peaks were noted, one at 2p24.3, the position 15.4 mega base (Mb), and the other at 2p23.2, 29.51 Mb. FISH and high resolution array CGH (aCGH) experiments disclosed an amplification of MYCN (16 Mb) and ALK (29.2-29.9 Mb), thus confirming the cCGH data. The combined visualization of sequence information and cCGH data drastically improves the resolution of the method to less than 2 Mb.</p>