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P Goetz

Publications and source records attributed to P Goetz.

At least 37 records · Page 2Linked to original sources
PubMed1998

Oncogene amplification and expression in pediatric solid tumors.

Oncogene amplification and expression and their mutual relationship was analyzed in 92 pediatric tumors by Southern and Northern blot hybridization with N-MYC, ERB A, ERB B, N-RAS and Shb probes. Amplification and overexpression was associated with more advanced clinical stages of tumor, especially in neuroblastomas, rhabdomyosarcomas and ganglioneuroblastomas. The most frequent alteration observed was N-MYC amplification together with overexpression. N-RAS amplification was not detected, while the overexpression of this oncogene was found in 3 cases. Neither amplification nor overexpression was revealed in any specimen of hepatoblastoma or hepatocellular carcinoma. We suggest that oncogenes overexpression provides more accurate prognostic information than amplification.

Child↗
PubMed1997

[Tumor suppressor genes].

The main role of tumour suppressor genes is the inhibition of cell proliferation. Somatic mutations in these genes are found frequently in sporadic tumors. Germ line mutations in tumour suppressor genes are responsible for hereditary cancer syndromes. In a carrier of such a germ line mutation, a somatic mutation or loss of the remaining functional copy of the gene is sufficient for the complete loss of function of the tumour suppressor. Therefore the carriers of germ line mutations have a high risk of developing malignancies. Many tumour suppressor genes have been cloned and characterized recently and many others are intensively searched for. Protein products of these genes serve different cellular functions and many of them directly participate in the cell cycle control. The characterization of tumour suppressor genes is important both for the understanding of processes of carcinogenesis and for practical use in the diagnostics, prognostics and therapy of tumours.

Animals↗
PubMed1996

[A method for detection of germinal mutations in the p53 tumor suppressor gene].

BACKGROUND: The tumour suppressor gene p53 is exhibits somatic mutations in a high proportion of human tumours. In addition, there are cancer families suffering from the Li-Fraumeni syndrome, the members of which carry germ line mutations in this gene. The carriers of the p53 germ line mutations have a high risk of developing tumours. The genetic diagnosis of carriership of the mutation in the tumour family members is important for preventive measures and for eventual tumour therapy modification. METHODS AND RESULTS: We have developed a method for the detection of germ line mutations in the p53 gene based on non-radioactive SSCP and direct sequencing of PCR products. We have proved the efficiency of the method by finding known mutations in eight tumour cell lines. In our collection of tumour families we have detected polymorphisms in exons 4 and 6 of the p53 gene. In one family which conformed to the criteria of the Li-Fraumem syndrome we have found a novel germ line mutation in exon 5. CONCLUSIONS: The method developed by us is very simple and sensitive. The germ line mutations in the p53 gene are very rare.

Female↗
PubMed1996

[Amplification of oncogenes in solid tumors in children].

BACKGROUND: The objective of the work was detection of amplification of oncogenes N-MYC, N-RAS, C-ERB A, C-ERB B and adaptor tyrosine kinase Shb in a group of 92 child age tumours in an attempt to reveal clinical and histopathological associations. METHODS AND RESULTS: Amplifications of oncogenes were detected by means of Southern's transfer, hybridization with labelled probes and densitometric evaluation. Amplification of the N-MYC oncogene in child tumours can be considered a manifestation of progression of the disease with an adverse prognosis, in particular in neuroblastomas, where it corresponds also with the adverse histological finding. In a group of sarcomas N-MYC amplification was detected in advanced clinical stages, while in malignant lymphogranulomas of the Hodgkin type it was not found. In Wilms tumour it was detected sporadically. Amplifications of oncogenes ERB A and ERB B are rare, amplifications of the oncogene RAS were not observed. Coamplifications characterized progression of the disease, in case of neuroblastoma even very short survival. In hepatic malignancies oncogene amplification was not found even in advanced stages. CONCLUSIONS: Oncogene amplification characterizes progression in a number of child tumours and its application in clinical oncology is prognostically useful.

Child↗
PubMed1996

Molecular analysis of chromosome 21 in a patient with a phenotype of Down syndrome and apparently normal karyotype.

Down syndrome (DS) is caused in most cases by the presence of an extra chromosome 21. It has been shown that the DS phenotype is produced by duplication of only a small part of the long arm of chromosome 21, the 21q22 region, including and distal to locus D21S55. We present molecular investigations on a woman with clinically typical DS but apparently normal chromosomes. Her parents were consanguineous and she had a sister with a DS phenotype, who died at the age of 15 days. Repeated cytogenetic investigations (G-banding and high resolution banding) on the patient and her parents showed apparently normal chromosomes. Autoradiographs of quantitative Southern blots of DNAs from the patient, her parents, trisomy 21 patients, and normal controls were analyzed after hybridization with unique DNA sequences regionally mapped on chromosome 21. Sequences D21S59, D21S1, D21S11, D21S8, D21S17, D21S55, ERG, D21S15, D21S112, and COL6A1 were all found in two copies. Fluorescent in situ hybridization with a chromosome 21-specific genomic library showed no abnormalities and only two copies of chromosome 21 were detected. Nineteen markers from the critical region studied with polymerase chain reaction amplification of di- and tetranucleotide repeats did not indicate any partial trisomy 21. From this study we conclude that the patient does not have any partial submicroscopic trisomy for any segment of chromosome 21. It seems reasonable to assume that she suffers from an autosomal recessive disorder which is phenotypically indistinguishable from DS.

Adult↗
PubMed1996

[Oncogenes and the malignancy process].

An important group of genes for the development of neoplastic diseases are, in addition to tumour suppressor genes, protooncogenes. The latter are highly preserved genes present in a similar sequence in the cell genomes of different species (yeasts - man). They encode components of biochemical signalling pathways by which external mitotic signals stimulate cell proliferation and products which inhibit cell differentiation. The result of activation of protooncogenes into oncogenes (mutations, chromosomal rearrangements, amplifications, viral insertions, insertion mutagenesis) is in particular hyperstimulation of cells resulting in uncontrolled proliferation. Mutations are of the dominant type, elimination of one allele leads to the transformation of a protooncogene into an oncogene. Oncogenes are classified with regard to the transmission level of the mitogenic signal on which they act. Originally they were detected in the genome of oncogenic viruses. However, they do not form their constant and specific constituent, the virus acts as a vector which transmits cellular protooncogenes (or oncogenes) during the reproductive cycle from one cell to another. The activity of various types of oncogenes is the necessary prerequisite for the genesis and development of various neoplastic diseases. Detection of oncogene alterations provides in some instances important diagnostic, prognostic and therapeutic findings.

Gene Expression Regulation, Neoplastic↗
PubMed1996

[Transgenic animals in medicine].

Transgenic animals are an experimental model of human diseases and enable us to study pathophysiological mechanisms, the interaction between genetic environmental factors and new therapeutic approaches incl. Their long-term effect. By using various methods it introduces into the genome of the experimental organism alien genes which become expressed. Mutated genes are introduced as well as the regulation sequence of expression of various genes, the sequence disrupting a certain gene or gene construction. Investigations of transgenic animals, whose production is rapidly increasing, are used in all spheres of medicine and biology. The author presents some examples from the sphere of oncology, cardiovascular, pulmonary, inflammatory and immunological diseases, human reproduction and early ontogenetic development, neuropsychiatric diseases and toxicology.

Animals↗
PubMed1992

Mosaicism in 45,X Turner syndrome: does survival in early pregnancy depend on the presence of two sex chromosomes?

Cytogenetic and molecular genetic findings in 91 patients with Turner syndrome are reported. In 87 patients, chromosome studies were carried out both in lymphocyte and fibroblast cultures. Mosaicism was demonstrated in 58 of these patients (66.7%), whereas only 18 (20.7%) were apparent non-mosaic 45,X, and 11 patients (12.6%) showed non-mosaic structural aberrations of the X chromosome. Among the mosaic cases 16 (18.4% of all patients) displayed a second cell line containing small marker chromosomes. The association of Y-specific chromosomal material with the presence of marker chromosomes was demonstrated in 6 out of 7 mixoploid fibroblast cell lines by polymerase chain reaction amplification and by Southern-blot analysis. The observation of ring formation and morphological variability in vivo and in vitro, and the continuous reduction in the percentage of cells containing marker chromosomes in longterm cultivation experiments indicated an increased instability of marker chromosomes. The findings suggest that in vivo selection of structurally altered sex chromosomes exists. Thus, the observation of apparent non-mosaic 45,X chromosomal complements in liveborn individuals with Turner syndrome does not contradict the hypothesis that some degree of mosaicism is necessary for survival in early pregnancy.

Blotting, Southern↗
PubMed1992

[Screening for fragile X syndrome in handicapped boys].

From a group of 201 mentally retarded boys 149 were clinically and somatometrically examined. Chromosomal analysis for detection of a fra(X)-syndrome was undertaken, when more than 3 of the chosen examination parameters were suspicious or when anamnestic clues for X-chromosomally linked mental retardation were present. 89 boys fulfilled above requirements, 14 of these had a fra(X)-syndrome (15.7%). The following symptoms were found with outstanding frequency: hyperactivity, hypotonic muscles, enlargement of testes, increased length of hands, retarded development of speech, dermatoglyphic abnormalities. If more than 3 of these findings occur, a chromosomal analysis for exclusion of a fra(X)-syndrome should be performed.

Child↗
PubMed1991

[Diagnosis of Turner's syndrome 1965-1989: karyotype, age at diagnosis and determining signs].

Early diagnosis of Turner's syndrome makes possible optimal application of all procedures of substitution and symptomatic therapy and offers also psychological support to the parents and the patients. In 1965-1989 in two centres 135 girls with Turner's syndrome were detected, 72 with karyotype 45, X, 63 with a chromosomal mosaic and/or structural anomaly. Girls and women with karyotype 45, X are detected sooner (9.4 +/- 6.9 years, as compared with 14.2 +/- 8.1 years, p = 0.0003). Before the age of three 28% of the girls with karyotype 45, X were detected (by congenital lymphoedemas, coarctation of the aorta, poor progress), only 9% of the others. Growth impairment revealed the diagnosis in 27% of the affected girls. Girls with karyotype 45, X were diagnosed on account of impaired growth sooner (7.9 +/- 2.2 years as compared with 11.8 +/- 2.7 years, p = 0.00005). At a time when the diagnosis of girls with karyotype was practically completed, 16% of the spontaneously maturing and menstruating women with chromosomal mosaic where the syndrome was detected during examination of sterility or habitual abortion were still not diagnosed.

Age Factors↗
PubMed1990

[Gonadal dysgenesis].

The authors describe six patients, female phenotype with karyotype 45X/46XY. Two girls suffered from pure gonadal dysgenesis, four from mixed gonadal dysgenesis. The authors emphasize the intact axis hypothalamus-pituitary gonads. In the above diagnoses the authors recommend revision and extirpation of the gonads with regard to possible malignant growth in the dysgenetic gonad.

Adolescent↗
PubMed1990

[Factors affecting the prognosis of acute lymphoblastic leukemia in childhood].

The authors tried to test the value of some clinical and laboratory characteristics for the prognosis of acute lymphoblastic leukaemia (ALL) in a group of 69 children treated according to three different protocols. The results were evaluated by methods of one-dimensional and multidimensional analysis. The absolute number of blasts in the peripheral blood stream and initial leucocytosis during establishment of the diagnosis proved to be the most important risk factors influencing the prognosis of the patients. Other adverse signs for the prognosis of ALL in the group were a mediastinal tumour, L2 type of leukaemic blasts according to the morphological FAB classification and age above 10 years when the diagnosis was established. The patient's sex, immunophenotype of the leukaemic blasts, chromosomal abnormality of the karyotype in the leukaemic cells, marked hepatosplenomegaly, thrombocytopenia, haemoglobin values and PAS reaction in the blasts, did not affect the therapeutic results in the author's group of patients.

Adolescent↗
PubMed1990

The importance of blast cell DNA content for prognosis of childhood acute lymphoblastic leukemia.

The prognostic value of cellular DNA content measured by static cytophotometry was evaluated in 69 children with acute lymphoblastic leukemia (ALL) using the pretreatment distribution of the DNA content in blast cells of bone marrow and peripheral blood. The median follow-up of the whole group of patients was 45 months. Aneuploidy was detected in 71% of children, most of them showing a hyperdiploid content (DNA index greater than 1.05). The duration of complete remission was significantly longer in patients with distinct hyperdiploid DNA content (DNA index greater than 1.16) than in those with less hyperdiploid and diploid DNA content (DNA index less than 1.16). The results achieved by static cytophotometry were compared with flow cytometry analysis and with cytogenetic investigations of chromosomal abnormalities in leukemic cells. Higher correlation was found between flow cytometry and cytogenetics. Flow cytometry proved to be a more convenient method for detection of the DNA content in leukemic cells than static cytophotometry.

Adolescent↗
PubMed1989

Correlations of clinical and laboratory data for prognosis in childhood acute lymphoblastic leukemia.

Correlation of 24 different clinical and laboratory measures was performed for a calculation of the prognosis in 65 children with newly diagnosed acute lymphoblastic leukemia (ALL). The hematologic as well as genetic parameters were studied at the time of diagnosis. It was shown that the initial blast count in peripheral blood is the most important risk factor for the prognosis of ALL. Cytogenetic, DNA cytometric, and pedigree data correlate with blast count and also seem to be very important determinants for ALL prognosis. The statistically significant increase in the incidence of neoplasms in ALL families is reported.

Child↗