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S Bodner

Publications and source records attributed to S Bodner.

15 recordsLinked to original sources
PubMed1999

Tumor spectrum in ARF-deficient mice.

The p19ARF product of the INK4a/ARF locus is induced in response to potentially oncogenic hyperproliferative signals and activates p53 by interfering with its negative regulator, Mdm2. Mice lacking ARF are highly prone to tumor development, and in this study, 80% of these animals spontaneously developed tumors and died within their first year of life. Mice that were heterozygous for ARF also developed tumors after a longer latency, whereas their wild-type littermates did not. In heterozygotes, tumor formation was accompanied by loss of the residual ARF allele and/or lack of ARF mRNA expression, implying that ARF can act as a canonical "two-hit" tumor suppressor gene. Tumors occurred earlier in life in ARF-null animals that were neonatally irradiated or given dimethylbenzanthrene, and several animals treated with carcinogen simultaneously developed multiple forms of malignancy arising from distinct cell lineages. Although p53-null mice primarily develop lymphomas and fibrosarcomas, the frequency of these two tumor types was inverted in ARF-null animals, with undifferentiated sarcomas predominating in a 3:2 ratio; 28% of ARF-null animals developed carcinomas and tumors of the nervous system, which have been rarely observed in untreated p53-null mice. The longer latency of tumor formation in ARF-null versus p53-null mice, therefore, appears to enable a broader spectrum of tumors to emerge.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1998

Stat5a and Stat5b proteins have essential and nonessential, or redundant, roles in cytokine responses.

A variety of cytokines mediate the activation of Janus protein tyrosine kinases (Jaks). The Jaks then phosphorylate cellular substrates, including members of the signal transducers and activators of transcription (Stat) family of transcription factors. Among the Stats, the two highly related proteins, Stat5a and Stat5b, are activated by a variety of cytokines. To assess the role of the Stat5 proteins, mutant mice were derived that have the genes deleted individually or together. The phenotypes of the mice demonstrate an essential, and often redundant, role for the two Stat5 proteins in a spectrum of physiological responses associated with growth hormone and prolactin. Conversely, the responses to a variety of cytokines that activate the Stat5 proteins, including erythropoietin, are largely unaffected.

Animals↗
PubMed1998

Jak2 is essential for signaling through a variety of cytokine receptors.

A variety of cytokines activate receptor-associated members of the Janus family of protein tyrosine kinases (Jaks). To assess the role of Jak2, we have derived Jak2-deficient mice. The mutation causes an embryonic lethality due to the absence of definitive erythropoiesis. Fetal liver myeloid progenitors, although present based on the expression of lineage specific markers, fail to respond to erythropoietin, thrombopoietin, interleukin-3 (IL-3), or granulocyte/macrophage colony-stimulating factor. In contrast, the response to granulocyte specific colony-stimulating factor is unaffected. Jak2-deficient fibroblasts failed to respond to interferon gamma (IFNgamma), although the responses to IFNalpha/beta and IL-6 were unaffected. Lastly, reconstitution experiments demonstrate that Jak2 is not required for the generation of lymphoid progenitors, their amplification, or functional differentiation. Therefore, Jak2 plays a critical, nonredundant role in the function of a specific group of cytokines receptors.

Animals↗
PubMed1998

Upper airway obstruction and pulmonary abnormalities due to lymphoproliferative disease following bone marrow transplantation in children.

We report three patients who developed severe supraglottic airway obstruction due to Epstein-Barr virus lymphoproliferative disease following allogeneic bone marrow transplantation. In addition to enlarged pharyngeal lymphoid tissue seen in all three patients, two had supraglottic airway narrowing and two developed pulmonary lymphoproliferative disease. They were treated with unmanipulated T cells or EBV-specific cytotoxic T lymphocytes. Life-threatening upper airway obstruction is a radiologically detectable complication of allogeneic bone marrow transplantation in children.

Adolescent↗
PubMed1992

p53 gene mutations in non-small-cell lung cancer cell lines and their correlation with the presence of ras mutations and clinical features.

We screened 77 non-small-cell lung cancer (NSCLC) cell lines for mutations of the p53 gene using a single-strand conformation polymorphism (SSCP) assay. We found that 57 cell lines (74%) had mutations of the p53 gene. Three cell lines had a deletion of the p53 gene. Of the remaining 54 cell lines, 49 cell lines were sequenced and 52 mutations were confirmed. In contrast to previously published p53 mutations in other human tumors, the p53 gene mutations in NSCLC were diverse with regard to the location and nature of the mutations. The region corresponding to codons 144-166, which is outside the evolutionarily conserved regions, was a frequent site of p53 gene mutations in NSCLC. The presence of a p53 gene mutation was not associated with age, sex, histological types, culture site, treatment intent, presence of prior cytotoxic treatment, neuroendocrine differentiation, median culture time or patient survival. The prevalence of p53 mutations in cell lines with ras mutations did not differ from that in cell lines without ras mutations. However, p53 gene mutations in NSCLC cell lines with ras mutations tended to cluster in exon 8, suggesting the presence of a functional domain of the p53 gene relating to interaction with the ras gene. We conclude that p53 and ras mutations are frequent and apparently independent genetic alterations which play different roles in the pathogenesis, progression and prognosis of NSCLC.

Amino Acid Sequence↗
PubMed1992

High frequency of somatically acquired p53 mutations in small-cell lung cancer cell lines and tumors.

We analysed the p53 open reading frame (ORF) in 16 small-cell lung cancer (SCLC) cell lines by direct sequencing of cDNA/PCR products and in 20 SCLC tumors by chemical cleavage and single-strand conformation polymorphism analyses of genomic DNA/PCR products. Abnormalities of p53 were found in 16/16 cell lines (100%) and in 16/20 tumors (80%). In the SCLC cell lines, mutations (59% missense, 18% nonsense and 23% splicing) changing the coding sequence were dispersed between amino acids 68 and 342. In the tumor samples, while the mutations occurred predominantly in exons 5-8, other mutations were located outside these regions. G to T transversions were common, occurring in 32% of the cases. We found no p53 mutations in the corresponding normal tissue from 19 patients whose tumors had p53 lesions, indicating that the mutations were all somatically acquired. In analysing the clinical data of the patients we found no correlation between tumor response to therapy or survival and the location or type of mutations. We conclude from these data that: (1) p53 mutations are found in SCLC with high frequency; (2) p53 mutations in a significant fraction of cases generate cDNAs with nonsense or splicing mutations; and (3) to date, these mutations have all been somatically acquired events.

Base Sequence↗
PubMed1989

Benign brain stem lesions in pediatric patients with neurofibromatosis: case reports.

The symptoms and clinical courses of 4 patients with neurofibromatosis and lesions of the brain stem identifiable on computed tomographic and/or magnetic resonance imaging scans are described. Two patients underwent biopsy and both had low-grade astrocytomas with no evidence of anaplasia. Both received radiation and chemotherapy. The other 2 patients have been monitored without biopsy or treatment. Three patients are alive and clinically stable, having been followed up for an average of 4 years; neuroimaging studies have shown no change in their tumors. The fourth patient died of a supratentorial primitive neuroectodermal tumor. Imaging studies had shown no change in his brain stem lesion, which at autopsy was found to be a focal collection of fibrillary astrocytes. These data suggest that some patients with brain stem lesions and neurofibromatosis may have a prognosis distinctly different from that of the typical patient with a brain stem glioma. We recommend caution against aggressive operative and adjuvant therapy for brain stem lesions in patients with neurofibromatosis, unless progression of the lesion is documented clinically and/or by imaging.

Adolescent↗
PubMed1981

Prednisone-responsive aplastic anemia associated with T-lymphocyte proliferation.

In some cases, bone marrow aplasia has been thought to result from immunologic abnormalities. Our patient had severe transfusion-dependent aplastic anemia, which responded to treatment with prednisone on two occasions. The exacerbations of aplastic anemia were associated with lymphocytic proliferation which on one occasion had the characteristics of T-cell chronic lymphocytic leukemia. Though he had had mild lymphoproliferation for a number of years, he ultimately died with progressive diffuse lymphoid infiltration of the bone marrow and other organs. The simultaneous occurrence of the T-cell lymphoproliferation and aplastic anemia and their simultaneous response to therapy suggests that this may be a clinical example of T-lymphocyte mediated suppression of erythropoiesis.

Anemia, Aplastic↗
PubMed1980

Scanning and transmission electron microscopic studies of complement-mediated lysis and antibody-dependent cell-mediated cytolysis of herpes simplex virus-infected human fibroblasts.

The morphologic aspects of complement-mediated and antibody-dependent cell-mediated cytolysis (ADCC) of human fibroblasts (HuFs) infected by herpes simplex virus (HSV) is described. Human antiviral antibody (antiHSV) was shown by transmission and scanning electron microscopy (TEM and SEM) to cause the deposition of an amorphous material over the surface of infected cells and virus particles. Associated with antiHSV treatment, the HuFs underwent endocytosis, with the appearance of pinocytotic vesicles immediately beneath the plasma membrane. The addition of complement resulted in lysis of the infected HuFs and massive dilatation of the perinuclear cisternae, but the virus particles associated with the cell surface did not appear lysed. Instead, an additional deposit was noted on the enveloped particles after the addition of complement (C). Human peripheral blood mononuclear leukocytes (MNLs) also lysed the antibody-coated, infected HuFs. Lymphocytes formed broad-based areas of attachment to the antiHSV-treated cells. Beneath these areas of contact occurred focal cytoplasmic changes that preceded cell lysis. Monocytes showed multiple points of binding and sent cytoplasmic projections over the surface of the infected HuFs. Virus particles and segments of target cell cytoplasm were gathered into vacuoles of the monocyte. In accord with the above morphologic findings, the relative roles that antibody, C, and leukocytes may play in human viral diseases is discussed.

Antibody-Dependent Cell Cytotoxicity↗
PubMedDate not supplied

Clear cell sarcoma of soft tissues in children and young adults: the St. Jude Children's Research Hospital experience.

Clear cell sarcoma is a rare soft tissue neoplasm whose clinical behavior and outcome has not been previously characterized. This study reviewed the clinical characteristics and outcome of all children with clear cell sarcoma of the soft tissues who were treated at St. Jude Children's Research Hospital from March 1962 through August 1998. Of 225 children with nonrhabdomyosarcomatous soft tissue sarcomas, 5 (2.2%) were diagnosed with clear cell sarcoma. Median age at diagnosis was 15 years 3 months. Primary sites included the extremities (n = 3), chest wall (n = 1), and abdomen (n = 1). At diagnosis 3 patients had localized disease. Following surgical resection (n = 3), radiotherapy (n = 2), and chemotherapy (n = 1) all three survive disease-free 10, 11, and 90 months after diagnosis, respectively. The remaining two patients with metastatic disease at diagnosis died 21 days and 9 months after diagnosis. Clear cell sarcoma of the soft tissues is rare in pediatrics. Complete surgical resection with negative margins is the most effective treatment for this disease. Patients with metastatic disease are candidates for multiinstitutional chemotherapy trials.

Adolescent↗
PubMedDate not supplied

Dermatofibrosarcoma protuberans: the pediatric experience at St. Jude Children's Research Hospital.

The clinical characteristics and outcome of children with dermatofibrosarcoma protuberans (DFSP) treated at a single institution over a 34-year period were reviewed. A retrospective chart review identified five children with dermatofibrosarcoma protuberans. The diagnosis was confirmed in all cases by one of the authors. Age; sex; clinical group; tumor invasiveness and size, nodal status, and metastases (TNM stage); therapy; and outcome were retrieved from the medical records of these patients. The median age at diagnosis was 12.5 years. There were four boys, and all tumors arose in the extremities or trunk. All children underwent at least two surgical procedures to achieve negative or surgically microscopic positive margins. In addition, one patient received adjuvant radiotherapy for microscopically positive margins. All patients survive free of disease 1 month to 16.5 years after diagnosis. Dermatofibrosarcoma protuberans is rare among children and adolescents. Recognition of this pathologic entity is important for its proper treatment. Surgical resection (with 3-cm margins) is currently the standard therapy for DFSP.

Adolescent↗