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Daynna J Wolff

Publications and source records attributed to Daynna J Wolff.

At least 19 recordsLinked to original sources
PubMed2007

HER2 testing: a review of detection methodologies and their clinical performance.

The ERBB2 proto-oncogene, commonly referred to as the human epidermal growth factor receptor-2 (HER2) gene, encodes a 185 kd receptor tyrosine kinase. Overexpression of the protein leads to constitutive activity of the HER2 receptor and breast tumor development through enhanced cell proliferation, survival, motility and adhesion. Overabundance of the HER2 receptor, typically caused by amplification of the HER2 gene, is present in approximately 10-30% of invasive breast cancers, and is associated with an aggressive disease course and decreased disease-free and overall survival in node-positive patients. Tratuzumab, a humanized murine monoclonal antibody, offers a targeted treatment modality for tumors that over express the HER2 protein. Tratuzumab, shown to be effective and initially approved for treatment of metastatic breast cancer, has recently been shown to be very effective in the adjuvant setting. Thus, to offer prognostic information and to direct appropriate treatment it is important to provide accurate laboratory assessment of the status of HER2. This article provides an overview of the methods currently used to assess HER2.

Breast Neoplasms↗
PubMed2006

Pediatric T-cell acute lymphoblastic leukemia with aberrations of both MLL loci.

Translocations involving the MLL gene at 11q23 have been implicated in acute lymphoblastic leukemia (ALL), as well as acute myeloid leukemia (AML). Such translocations result in gain of function fusion proteins that drive cell proliferation. Except in cases of T-cell ALL, MLL rearrangement is typically associated with a poor prognosis. We report a case of T-cell ALL with a t(11;19)(q23;p13.3) and deletion of the other chromosome 11 homolog at band q23. Fluorescence in situ hybridization (FISH) analyses confirmed involvement of the MLL loci in both the translocation and deletion. This case is unique in that deletions of 11q23 reported in ALL generally do not involve MLL. We are unaware of a previous report showing rearrangement of the MLL loci on both chromosome 11 homologues.

Child↗
PubMed2006

Altered promoter usage characterizes monoallelic transcription arising with ERBB2 amplification in human breast cancers.

Analysis of a collection of human breast cancers (n = 150), enriched in ERBB2-positive cases (n = 57) and involving tumor genotyping relative to population-matched blood genotyping (n = 749) for a common ERBB2 single nucleotide polymorphism Ala(G)1170Pro(C), revealed that ERBB2 amplification in breast cancer is invariably monoallelic. Analysis of paired breast cancer and blood samples from informative (G1170C heterozygotic) ERBB2-positive (n = 12) and ERBB2-negative (n = 17) cases not only confirmed monoallelic amplification and ERBB2 transcriptional overexpression but also revealed that most low ERBB2 expressing breast cancers (12/17) exhibit unbalanced allelic transcription, showing 3-fold to nearly 5,000-fold preferential expression from one of two inherited alleles. To explore cis-acting transcriptional mechanisms potentially selected during ERBB2 amplification, levels of four different ERBB2 transcript variants (5.2, 4.7, 2.1, and 1.4 kb) were correlated with total (4.6 kb) ERBB2 mRNA levels in ERBB2-positive (n = 14) versus ERBB2-negative (n = 43) primary breast cancers. Relative expression of only the 2.1 kb extracellular domain-encoding splice variant and a 4.7 kb mRNA variant that uses an alternative start site were significantly increased in association with ERBB2-positivity, implicating altered promoter usage and selective transcript regulation within the ERBB2 amplicon. Altogether, these findings provide new mechanistic insights into the development of ERBB2-positive breast cancer and strong rationale for delineating candidate cis-acting regulatory elements that may link allele-specific ERBB2 transcription in premalignant breast epithelia with subsequent development of breast cancers bearing monoallelic ERBB2 amplicons.

Alleles↗
PubMed2006

Detection of an apparent homozygous 3120G>A cystic fibrosis mutation on a routine carrier screen.

A 28-year-old Caucasian female with no personal or family history of cystic fibrosis (CF) presented for preconception counseling and screening. Cystic fibrosis transmembrane conductance regulator (CFTR) mutation analysis using the Inno-LiPa CFTR assay revealed lack of hybridization for both the wild-type and mutant oligonucleotides for 3120+1G>A. This region was sequenced, and an apparent homozygous 3120G>A mutation was detected. Additional testing revealed an abnormal sweat chloride (77 mmol/L). Review of systems was essentially unremarkable with an absence of sinus symptoms, occasional nonproductive cough, and no features of malabsorption. Physical examination, chest X-ray, and pulmonary function tests were within normal limits. Only two other patients (siblings) with homozygous 3120G>A mutations have been reported (http://www.genet.sickkids.on.ca/cftr/). Both siblings had pancreatic insufficiency, mild pulmonary symptoms, and abnormal sweat chloride levels. Our findings suggest that a homozygous mutation of a G>A conversion at 3120 is associated with abnormal CFTR function and either a mild form of CF or no overt symptoms of disease, emphasizing the difficulties in assigning genotype/phenotype correlation.

Adult↗
PubMed2006

HER-2 fluorescence in situ hybridization: results from the survey program of the College of American Pathologists.

CONTEXT: Fluorescence in situ hybridization (FISH) is a common method used to determine HER-2 status in breast cancer. Limited information is available concerning reproducibility of FISH in determining HER-2 gene amplification. OBJECTIVE: To present proficiency testing results of FISH for HER-2 conducted by the Cytogenetics Resource Committee of the College of American Pathologists/American College of Medical Genetics. DESIGN: During the past 5 years, unstained sections from 9 invasive breast carcinomas were used for HER-2 FISH proficiency testing, allowing for comparison of FISH results among a large number of laboratories. Additional data were collected using an educational (ungraded) challenge and supplemental questions in the surveys. RESULTS: The number of laboratories participating in HER-2 FISH proficiency testing has increased steadily during the past 5 years (from 35 in 2000 to 139 in 2004). Reproducibility of test results among laboratories was excellent for breast tumors with low copy number (no HER-2 amplification) and for breast tumors with high copy number (HER-2 amplification). However, there was considerable variation in interpretation of results for a tumor with low-level HER-2 amplification that was tested on 2 separate occasions. Responses to supplemental questions indicated that there was a need for consensus on the use of a separate equivocal/borderline interpretative category and the need for standardization of cutoff values used to define interpretative categories. CONCLUSIONS: The College of American Pathologists proficiency survey programs provide useful information concerning the reproducibility of clinical testing for HER-2 by FISH and reflect clinical interpretation of HER-2 FISH analyses from laboratories across the country.

Adenocarcinoma↗
PubMed2006

Cytogenetic heteromorphisms: survey results and reporting practices of giemsa-band regions that we have pondered for years.

CONTEXT: Cytogenetic heteromorphisms (normal variants) pose diagnostic dilemmas. Common Giemsa-band heteromorphisms are not described in the literature, although Giemsa-banding is the method most frequently used in cytogenetic laboratories. OBJECTIVE: To summarize the responses from more than 200 cytogeneticists concerning the definition and reporting of cytogenetic heteromorphisms, to offer these responses as a reference for use in clinical interpretations, and to provide guidance for interpretation of newly defined molecular cytogenetic heteromorphisms. DESIGN: The Cytogenetics Resource Committee of the College of American Pathologists and the American College of Medical Genetics administered a proficiency testing survey in 1997 to 226 participant cytogenetic laboratories. Supplemental questions asked whether participants considered particular Giemsa-banded chromosomal features to be heteromorphisms and if these would be described in a cytogenetic clinical report. RESULTS: Responses were obtained from 99% of participants; 61% stated they would include selected heteromorphism data in a clinical report. More than 90% considered prominent short arms, large or double satellites, or increased stalk length on acrocentric chromosomes to be heteromorphisms; 24% to 36% stated that they would include these in a clinical report. Heterochromatic regions on chromosomes 1, 9, 16, and Y were considered heteromorphisms by 97% of participants, and 24% indicated they would report these findings. Pericentric inversions of chromosomes 1, 2, 3, 5, 9, 10, 16, and Y were considered heteromorphisms with more than 75% of respondents indicating they would report these findings. CONCLUSIONS: Responses were not unanimous, but a clear consensus is presented describing which Giemsa-band regions were considered heteromorphisms and which would be reported.

Azure Stains↗
PubMed2005

Establishment of epidermal cell lines derived from the skin of the Atlantic bottlenose dolphin (Tursiops truncatus).

The Atlantic bottlenose dolphin (Tursiops truncatus), a marine mammal found off the Atlantic coast, has become the focus of considerable attention because of an increasing number of mortality events witnessed in this species over the last several years along the southeastern United States. Assessment of the impact of environmental stressors on bottlenose dolphins (BND) has been difficult because of the protected status of these marine mammals. The studies presented herein focused on establishing epidermal cell cultures and cell lines as tools for the in vitro evaluation of environmental stressors on BND skin. Epidermal cell cultures were established from skin samples obtained from Atlantic BND and subjected to karyotype analysis. These cultures were further characterized using immunohistochemical methods demonstrating expression of cytokeratins. By two-dimensional polyacrylamide gel electrophoresis (2D-PAGE), we observed that the proteomic profile of BND skin tissue samples shared distinct similarities with that of skin-derived cultures. Epidermal cell cultures were transfected with a plasmid encoding the SV40 small t- and large T-antigens, as well as the neomycin-resistance gene. Five neomycin-resistant clones were isolated and expanded, and all of them proliferated at a faster rate than nontransfected BND epidermal cultures, which exhibited signs of senescence. Cell lysates prepared from two transfected clones were shown to express, by Western blot analysis, both SV40 tumor antigens. These experimental results are consistent with the concept that transfected clones expressing SV40 tumor antigens represent immortalized BND cell lines. Epidermal cell lines derived from Tursiops truncatus will provide a unique tool for studying key features of the interaction occurring between dolphins and the environment in which they live at their most crucial interface: the skin.

Animals↗
PubMed2005

Developing a sustainable process to provide quality control materials for genetic testing.

PURPOSE: To provide a summary of the outcomes of two working conferences organized by the Centers for Disease Control and Prevention (CDC), to develop recommendations for practical, sustainable mechanisms to make quality control (QC) materials available to the genetic testing community. METHODS: Participants were selected to include experts in genetic testing and molecular diagnostics from professional organizations, government agencies, industry, laboratories, academic institutions, cell repositories, and proficiency testing (PT)/external Quality Assessment (EQA) programs. Current efforts to develop QC materials for genetic tests were reviewed; key issues and areas of need were identified; and workgroups were formed to address each area of need and to formulate recommendations and next steps. RESULTS: Recommendations were developed toward establishing a sustainable process to improve the availability of appropriate QC materials for genetic testing, with an emphasis on molecular genetic testing as an initial step. CONCLUSIONS: Improving the availability of appropriate QC materials is of critical importance for assuring the quality of genetic testing, enhancing performance evaluation and PT/EQA programs, and facilitating new test development. To meet the needs of the rapidly expanding capacity of genetic testing in clinical and public health settings, a comprehensive, coordinated program should be developed. A Genetic Testing Quality Control Materials Program has therefore been established by CDC in March 2005 to serve these needs.

Centers for Disease Control and Prevention, U.S.↗
PubMed2005

Fluorescence in situ hybridization for detecting transitional cell carcinoma: implications for clinical practice.

OBJECTIVE: To determine the diagnostic sensitivity of genetic studies using fluorescence in situ hybridization (FISH) for detecting both new and recurrent cases of transitional cell carcinoma (TCC) in a routine clinical practice setting, as bladder cancer has a significant risk of recurrence and progression to invasive disease and thus sensitive surveillance testing is very important. PATIENTS AND METHODS: FISH was performed using the UroVysion kit (Vysis Inc., Downers Grove, IL, USA) Consecutive patients were assessed using FISH, both to evaluate those with a history of TCC or with suspicious symptoms, and the FISH results were compared with concurrent biopsy and cytological assessments. RESULTS: In all, 521 consecutive FISH tests from 300 patients were evaluated; 47% had a history of bladder cancer and 53% had suspicious symptoms. Of the 521 FISH tests, 24% were positive; concurrent cytology was available for 84% of the FISH tests, with a concordance rate of 78% (6% were positive for both and 72% were negative by both tests). For the discordant cases, FISH was positive and cytology negative in 21% of cases, and cytology was positive with a negative FISH for 1%. In all, 99 FISH tests had concurrent biopsy data. Of the 44 cases histologically positive for TCC, 32 were FISH-positive, resulting in an overall sensitivity (95% confidence interval) of 73 (60-88)%. FISH detected 95% of cases with high-grade carcinoma, while only seven of these 17 were positive by concurrent cytological assessment. FISH detected 56% and cytology detected 32% of low-grade lesions. FISH detected all nine new cases with positive histology. Overall, the specificity of FISH was 65 (53-78)%. Of 112 patients with previous TCC, 28 had a recurrence; 22 of these had positive FISH results. CONCLUSION: FISH analysis has a high sensitivity for detecting new cases of TCC, as well as recurrences. From the present data FISH is considerably more sensitive and only slightly less specific than cytology in diagnosing TCC. Therefore, we recommend FISH as a useful initial diagnostic tool in patients suspected of both new and recurrent TCC.

Adult↗
PubMed2004

Mosaic duplication 1(q11q44) in an infant with nephroblastomatosis and mineralization of extraplacental membranes.

Partial trisomy of 1q is rare. Only 32 cases of isolated partial trisomy 1q have been previously reported. From these cases, a characteristic phenotype is beginning to emerge. We present a case of mosaic duplication of 1q [46,XX,dup (1)(q11q44)/46,XX]. Many features of our patient have been described in previous patients, thus supporting the emerging phenotype. Two particular features, however, have not been previously described. The present case demonstrated extensive mineralization of the extraplacental membranes and bilateral nephromegaly, with an extreme form of diffusely hyperplastic perilobar nephroblastomatosis. Clinical comparison is made between our case and previously reported cases, and the clinical significance of the unique findings are reviewed and discussed.

Abnormalities, Multiple↗
PubMed2004

Utility of Interphase FISH Panels for Routine Clinical Cytogenetic Evaluation of Chronic Lymphocytic Leukemia and Multiple Myeloma.

Specific genetic abnormalities are of prognostic significance for patients with chronic lymphocytic leukemia (CLL) and multiple myeloma (MM); however, routine cytogenetic analysis usually provides normal results. We utilized two probe panels for interphase fluorescence in situ hybridization (FISH) studies to enhance the ability to detect genetic abnormalities in samples that were referred for routine cytogenetic studies for possible diagnoses of CLL or MM. The CLL panel consisted of probes for 11q22.3 (ATM gene), 13q14 (D13S319), the centromere of chromosome 12 (D12Z3) and 17p13.1 (P53 gene). The MM panel included probes for 14q32 (IgH gene) and/or t(11:14)(q13;q32) (BCL1/IgH), 13q14 (D13S319) and 17p13.1 (P53 gene). FISH detected clonal aberrations not identified by conventional cytogenetics in an additional 8 of 23 (35%) samples referred for possible CLL and 7 of 42 (17%) samples with possible MM. The prognostic significance of the aberrations identified ranged from favorable, to intermediate, to poor. Our studies indicate that many samples referred for routine cytogenetics testing for CLL and MM yield normal results for both conventional and FISH testing, likely due to lack of definitive diagnosis in a percentage of cases. However, FISH is more sensitive for the detection of clinically significant chromosome abnormalities and should be the testing methodology of choice for these disorders.

Journal Article↗
PubMed2003

Clinical, genetic, and biophysical characterization of a homozygous HERG mutation causing severe neonatal long QT syndrome.

Previous studies have identified mutations in five ion channel genes as a cause of long QT syndrome, a heterogeneous disorder characterized by prolongation of the QT interval, multiform ventricular tachycardia (torsades de pointes), seizures, syncope, and sudden death. However, in these studies, the average age of initial symptoms is in the third decade of life or later, and few reports have described the genetic causes of long QT syndrome presenting in the prenatal or neonatal period. We used a candidate gene approach to identify the genetic cause of long QT syndrome in an infant whose initial manifestations were detected in utero. Direct bidirectional sequencing of long QT syndrome genes identified a previously unreported HERG missense mutation (R752Q). Three asymptomatic family members were heterozygous for R752Q, and the proband, who manifested ventricular tachycardia in utero, was homozygous. R752Q was not found in 100 normal unrelated chromosomes. Paternal DNA was unavailable for testing. Transient transfection of HERG generated robust IKr, but no current was observed for the mutant HERG. The HERG mutant, R752Q, is associated with a mild phenotype, inasmuch as family members with a heterozygous mutation appear unaffected. The homozygous mutation results in absence of functional IKr, causing a profound loss of HERG channel function, creating the equivalent of a "HERG knockout" and leading to a severe phenotype.

Base Sequence↗
PubMed2002

A testing algorithm for determination of HER2 status in patients with breast cancer.

The HER2 gene is amplified and overexpressed in 25-30% of breast carcinomas. Assessment of HER2 status for prognosis and treatment of breast cancer patients can be performed by immunohistochemistry and/or fluorescence in situ hybridization (FISH). To develop a testing algorithm for HER2 in breast cancers, we used FISH analysis to determine the HER2 gene copy number and immunostaining to detect the p185 protein. Interlaboratory, interobserver, and intermethod variabilities of immunohistochemistry were assessed. In 24 invasive breast carcinomas, the indices of HER2 status obtained by FISH and by a reference laboratory's DAKO HercepTest (immunostain) gave an overall concordance of 96%. The reference laboratory's stained slides were re-interpreted by an in-house panel of pathologists; the interpretation differed in one case. The panel's interpretations were concordant with the FISH results in all 24 cases. Interobserver variability for the panel's immunohistochemistry interpretations was assessed using three different immunostaining methods on 70 slides. The numerical (0-1+, 2+, 3+) scores showed greater variability among observers than did the overall positive/negative results. One pathologist reported inconsistent results in >30% of the slides evaluated. Borderline scoring of 1-2+ was reported in 18 slides (23%) by at least one observer. Incongruent interobserver immunohistochemistry scores, leading to different positive and negative interpretations, were obtained with 5 slides (7%). The majority of consensus positive cases exhibited strong membrane staining (3+). The majority of consensus negative cases scored as 0. Based on these observations, we developed a testing algorithm that maximizes the benefits of FISH and immunohistochemistry, providing physicians with accurate results for appropriate clinical care.

Algorithms↗
PubMedDate not supplied

Pilot assessment of the subtelomeric regions of children with autism: detection of a 2q deletion.

PURPOSE: Autism is a chronic neurodevelopmental disorder characterized by deficits in reciprocal social interaction, language and communication, and by the presence of stereotypical behaviors. The disorder is a complex genetic trait with no known predisposing genes. We report the results of a pilot project to screen for aberrations in the gene-rich subtelomeric chromosomal regions of a cohort of children with autism. METHODS: For our pilot project, we used a multiprobe system that includes probes for the subtelomeric regions of all human chromosomes. We assessed the subtelomeric regions of chromosomes from 10 children with a diagnosis of autism. RESULTS: The screen identified one child with an apparent deletion of the subtelomeric region of chromosome 2q; nine children and pooled control samples yielded normal results. The deletion in our patient was confirmed with two other subtelomeric probes and a targeted cytogenetic study revealed a subtle difference in appearance for one chromosome 2 homologue. CONCLUSION: There have been several reports of children with dysmorphic features, autistic behaviors, and 2q deletions detectable with standard cytogenetic techniques. It may be that the distal region of chromosome 2q harbors a gene or genes that may predispose to autism.

Autistic Disorder↗