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C Rudduck

Publications and source records attributed to C Rudduck.

At least 19 recordsLinked to original sources

Deletion of chromosome 13 detected by conventional cytogenetics is a critical prognostic factor in myeloma.

In myeloma, the prognostic impact of different strategies used to detect chromosome 13 deletion (Delta13) remains controversial. To address this, we compared conventional cytogenetics and interphase fluorescence in situ hybridization (iFISH) in a large multicenter study (n=794). The ability to obtain abnormal metaphases was associated with a poor prognosis, which was worse if Delta13, p53 deletion or t(4;14) was present, but only Delta13 remained significant on multivariate analysis. Patients with Delta13, by either cytogenetics or iFISH, had a poor prognosis. However, when cases with Delta13 detectable by both cytogenetics and iFISH were separated from those detected by iFISH only, the poor prognosis of iFISH-detectable Delta13 disappeared; their outcome matched that of patients with no detectable Delta13 (P=0.115). Addition of ploidy status to iFISH-Delta13 did not affect the prognostic value of the test. Indeed both cytogenetics and iFISH Delta13 divided both hyperdiploidy and nonhyperdiploidy into two groups with similar prognoses, indicating that the poor prognosis of ploidy is entirely due to its association with Delta13. We conclude that Delta13 detected by metaphase analysis is a critical prognostic factor in myeloma. Absence of Delta13, even in those patients yielding only normal or no metaphases, is associated with a relatively good prognosis.

Adult↗

Application of interphase cytogenetics to monitor bone marrow transplants.

Chromosomal in situ hybridization (ISH) has extended the scope of cytogenetic analysis to nondividing cells by the use of chromosome-specific probes detected by nonisotopic techniques. This provides a rapid and sensitive method for identifying chromosomes in interphase cells, and is useful in gauging engraftment following bone marrow transplantation, particularly when the number of cells obtained is minimal. We have performed ISH using a Y-heterochromatin-specific probe to monitor patients with malignant hematological disease who have received a sex-mismatched transplant. The results have been compared with those obtained from concurrently performed standard cytogenetic analysis. Host cells were detected by interphase cytogenetics in all patients posttransplant, at times varying from 28-1,825 days, whereas routine analysis detected host cells in only 4 patients, 3 of whom were found to be in relapse. The significance of the persistence of host cells is unknown, but it does not appear to indicate impending relapse.

Adolescent↗

Co-amplification of the gene for parathyroid hormone-related protein (PTHRP) and KRAS2 in a human lung cancer cell line.

Parathyroid hormone-related protein (PTHRP) is expressed in a large number of tumors and is the mediator of parathyroid hormone-like effects seen in humoral hypercalcemia of malignancy. The gene coding for PTHRP has been localised to the short arm of chromosome 12. This is at the same region as the oncogene KRAS2, and amplification of KRAS2 has previously been found in human lung cancer. The BEN cell line which is known to express PTHRP was established from a patient who had squamous cell carcinoma of the lung with hypercalcemia. Cytogenetic analysis of the BEN cell line revealed a very complex karyotype with many marker chromosomes. Chromosomal in situ hybridization with biotinylated DNA probes visualized by a biotin-streptavidin-polyalkaline-phosphatase complex was used to analyse two dicentric marker chromosomes containing homogeneously staining regions (hsr) in BEN. The hsr were found to contain amplified PTHRP and KRAS2 at levels of 30-fold and 14-fold per cell, respectively. The higher level of amplification of the PTHRP gene would suggest that PTHRP is the target gene of amplification in the amplicon. This is the first report of gene amplification of PTHRP and in addition its co-amplification with KRAS2.

Chromosome Aberrations↗

A simple G-banding technique following nonradioactive in situ hybridization.

A simple G-banding protocol has been found to be compatible with a nonisotopic in situ hybridization technique utilizing a biotin-streptavidin-polyalkaline phosphatase complex. The chromosomes are banded following detection of the hybridization signal, the procedure requires no pretreatment of cultures or special optical equipment, and it produces permanent preparations.

Chromosome Banding↗

Two malignant peripheral primitive neuroepithelial tumor cell lines established from consecutive samples of one patient: characterization and cytogenetic analysis.

A 6-year-old girl presented with a tumor of the right shoulder involving bone, adjacent soft tissue, and regional lymph nodes. The conventional histologic diagnosis was ambiguous, initially suggesting lymphoma. After relapse on lymphoma therapy, reevaluation with additional multiple diagnostic techniques performed on the biopsy tissue and on two cell lines derived from the biopsies established the diagnosis of a primitive neuroepithelial tumor of bone and soft tissue. This was strongly supported by 1) focal rosette formation by the tumor cells and positive immunostaining for neuron-specific enolase and synaptophysin, with absent staining for leukocyte common antigen; 2) at the ultrastructural level, formation of cellular processes containing microtubules, a paucity of neurosecretory granules, absence of synaptic junctions, formation of long "intermediate" junctions between cells, and, in culture, widespread development of rosettes; 3) marked surface positivity to W 6/32 and negativity to HSAN 1.2 antibodies; and 4) elevated expression of MYC and lack of overexpression of MYCN oncogenes. Numerical and structural abnormalities were present in the karyotype, but the expected t(11;22)(q24;q12) was not present in the tumor-involved marrow or in either of the established tumor cell lines, although there was an interstitial deletion of 11q involving breakpoints in q21 and q23.

Biomarkers, Tumor↗

Chromosomal localization of amplified N-myc in neuroblastoma cells using a biotinylated probe.

G-banded chromosome analysis of neuroblastoma cells from two children revealed homogeneously staining regions (hsr) in one patient and double minutes (dmin) in the other. Subsequently, both abnormalities were confirmed as areas of N-myc amplification using chromosomal in situ hybridization with a biotinylated N-myc probe. In addition, the first patient's karyotype contained a possible derivative chromosome 17, which was also demonstrated to contain amplified N-myc, indicating the presence of an hsr unidentified by G-banding. Intercellular heterogeneity in the degree of amplification was also identified in the nuclei of interphase cells. This technique provides a quick method for detecting gene amplification, the identification of which may have useful clinical implications.

Abdominal Neoplasms↗

Detection of MYCN amplification in three neuroblastoma cell lines by non-radioactive chromosomal in situ hybridization.

A non-radioactive chromosomal in situ hybridization technique utilizing a biotin-streptavidin-polyalkaline-phosphatase complex was successfully applied to three neuroblastoma cell lines for detection of MYCN amplification. These cell lines, designated PER-106, PER-107, and PER-108, were derived from consecutive bone marrow samples taken from a patient with stage IV neuroblastoma. The cell line derived at diagnosis (PER-106) exhibited MYCN amplification in the form of variable numbers of double-minute chromosomes, small fragments, and rings of varying sizes. This observed variability of MYCN amplification may explain the reported heterogeneity of both MYCN mRNA and protein expression among individual cells of some neuroblastomas. The cell lines derived from subsequent samples (PER-107 and PER-108) contained amplified MYCN as two consistent homogeneously staining regions in every cell. These were located on the short arms of chromosomes 6 and 14. Thus, amplified MYCN was identified in each cell line and demonstrated the concurrent evolution of amplification with cytogenetic abnormalities.

Biotin↗

Mitochondrial genome distribution in histochemically cytochrome c oxidase-negative muscle fibres in patients with a mixture of deleted and wild type mitochondrial DNA.

In situ hybridization studies were performed on a series of chronic progressive external ophthalmoplegia patients harbouring large mitochondrial DNA deletions, using intra- and extra-deletional probes. Clear differences in the distribution of wild type and deleted mitochondrial genomes were seen in both ragged-red and non-ragged red, cytochrome c oxidase-negative fibres, with an accumulation of deleted genomes in the subsarcolemmal zone. Wild type genome content was normal or decreased in the cytochrome c oxidase-negative regions of one case, but in two patients, wild type mtDNA content in cytochrome c oxidase-negative regions was either normal (most fibres) or increased (occasional fibres). The latter observation suggests there may be a stage in the natural history of ragged-red fibre evolution where wild type genomes are transiently increased. The significance of this finding is discussed.

Base Sequence↗

The proportion of erythroid mitoses in normal human bone marrow in short-term culture systems.

The proportion of erythroid cells in mitosis was determined in direct preparations and in synchronized and unsynchronized short-term cultures from normal human bone marrow. The stimulating effect on the proportion of erythroid mitoses of bovine serum albumin (BSA), erythropoietin (EP) and human leucocyte conditioned medium (HLC) derived from stimulated lymphocytes, was also analyzed in short-term marrow cultures. In synchronized and unsynchronized cultures, the proportion of erythroid mitoses was markedly lower than in direct preparations, with a mean of 75% in the direct compared to 11% in the unsynchronized cultures and 7% in synchronized. Statistical analysis showed that EP had a substantial influence on the erythroid cells while HCL had a minor effect.

Bone Marrow Cells↗

Gc serum groups in schizophrenia.

Gc subtypes were studied by isoelectric focusing in schizophrenic patients and controls. No significant differences between patients and controls were found. The results so far on Gc groups and schizophrenia show no consistent pattern and the significant associations reported have not been confirmed.

Blood Protein Electrophoresis↗

Haptoglobin and transferrin types in schizophrenia.

Haptoglobin and transferrin types were studied in schizophrenic patients and controls. In the haptoglobin system a significant departure from the Hardy-Weinberg equilibrium with an excess of heterozygotes was found among the patients (p less than 0.01). The distribution of haptoglobin types in the schizophrenic patients was significantly different from that in the controls. The distribution of transferrin types showed a good agreement with the Hardy-Weinberg equilibrium. There was no significant difference between patients and controls with respect to transferrin types.

Gene Frequency↗

Alpha 1-antitrypsin types in schizophrenia.

The gene and phenotype frequencies of alpha 1-antitrypsin were studied in patients with (49) and without (92) a family history of schizophrenia. A significant difference with respect to phenotype (p less than 0.05) and gene (p less than 0.025) frequencies was found between the two groups of patients. Among patients with a family history of schizophrenia there was a significant increase of the M1 gene and a decrease of the M2 gene. There were no significant differences between schizophrenic patients and controls.

Gene Frequency↗

Complement factor C4 in schizophrenia.

The complement factor C4 was studied in 165 schizophrenic patients and in 330 controls. A highly significant increase in the frequency of C4B deficiency (BQO) was found among the schizophrenic patients compared with controls (p less than 0.0005).

Complement C4↗

C3 and C6 complement types in schizophrenia.

C3 and C6 complement types were studied in schizophrenic patients and controls. The distributions of the three common C3 types (F, FS and S) among the patients was significantly different from that in the controls (p less than 0.005) and the frequency of the C3F gene was significantly increased (p less than 0.0005) among the patients. There were no significant differences in C6 gene or phenotype frequencies between patient and controls.

Complement C3↗

HLA antigens and clinical subgroups of schizophrenia.

Frequencies of HLA A, B, C, and DR antigens were studied in 100 schizophrenic patients and 919 controls from South Sweden. The patients were diagnosed according to the DSM III criteria and divided into four clinical subgroups (hebephrenic, paranoid, residual, and undifferentiated). In the schizophrenic patients as a whole significant increases were found for A2, A3, B17, B27, and Cw2 and decreases for A1, A11, and B8. A previous positive association with A9 from the same population was not confirmed. A significant heterogeneity between the four clinical subgroups was found for A3 and Bw35. Most of the associations between HLA antigens and schizophrenia reported in the literature appear to be fortuitous and dependent on the large number of trials made. However, confirmed increases have been found for A9 and B17, and confirmed decreases have been observed for A1 and B7. Some evidence for a heterogeneity between clinical subgroups was found in the present as well as in previous investigations.

HLA Antigens↗

HLA antigens in patients with and without a family history of schizophrenia.

Frequencies of HLA antigens (A, B, C and DR) were studied in patients with (n = 49) and without (n = 67) a family history of schizophrenia and in controls. Among the patients with a family history of schizophrenia significant increases were found in the A3 and B5 antigens while significant decreases were observed for the A1, A11 and B8 antigens. In a material of schizophrenic siblings the sharing of HLA haplotypes was consistent with normal segregation.

Gene Frequency↗

Properdin factor B (Bf) types in schizophrenia.

The phenotype frequencies of properdin factor B (Bf) were studied in patients with (n = 47) and without (n = 66) a family history of schizophrenia and in controls. In patients with a family history of schizophrenia, a significant decrease of the FS type was found. No significant difference was found between patients without a family history of schizophrenia and controls.

Complement Factor B↗