PubMed Health⌕ Search

Biomedical subjects

J Casper

Publications and source records attributed to J Casper.

At least 91 records · Page 5Linked to original sources

Activity of cytostatic drugs in two heterotransplanted human testicular cancer cell lines with different sensitivity to standard agents.

Two established human testicular cancer cell lines were used in a mouse xenograft model to assess the antitumour activity of 15 anticancer agents. Line H 12.1 was highly sensitive to cisplatin, bleomycin and vinblastine, resembling non-pretreated testicular tumours, whereas line H 23.1 showed resistance to cisplatin and vinblastine, comparable to tumours with acquired or intrinsic drug resistance. In line H 12.1 several drugs were highly active, including cyclophosphamide, ifosfamide, nimustine and vincristine; carmustine, vindesine, doxorubicin, epidoxorubicin, pirarubicin, mitoxantrone, carboplatin and iproplatin had only moderate activity. In line H 23.1 only cyclophosphamide, ifosfamide, nimustine, vincristine and bleomycin had antitumour activity. These two cell lines represent a useful model for preclinical evaluation of new agents with presumed activity in testis cancer.

Animals↗

Treatment of meningeal relapse in childhood acute lymphoblastic leukemia: II. A prospective study of intellectual loss specific to CNS relapse and therapy.

Changes in intellectual function during the course of treatment for acute lymphocytic leukemia were studied. Twenty-four children had baseline psychological evaluations and annual reevaluations for 3-6 years postdiagnosis. Treatment in all patients included combination chemotherapy, 2,400 cGy prophylactic cranial irradiation, and intrathecal methotrexate. Central Nervous System (CNS) relapse occurred in eight of these children. It was then treated with 3,000 cGy cranial plus 1,800 cGy spinal irradiation. Patients who remained in continuous complete remission showed no decline in global intelligence quotient (IQ). Patients who experienced CNS relapse had a mean decline of 16 IQ points by 3 years postdiagnosis and the long-term survivors displayed a mean loss of 25 IQ points 5-6 years postdiagnosis. Three of the five long-term survivors of CNS relapse function within the retarded range of mental ability and require special education. The other two have learning problems and display poor academic performance relative to same-age peers. There was no association noted between age at diagnosis and ultimate loss of IQ points. This prospective study suggests that children who receive a second course of cranial irradiation for treatment of CNS relapse are at high risk for significant and progressive intellectual loss.

Antineoplastic Combined Chemotherapy Protocols↗

Cellular oncogenes in human teratocarcinoma cell lines.

We have analysed, by Northern blots, the expression of 14 cellular oncogenes in nine cell lines established from human teratocarcinomas. All lines expressed considerable amounts of p53, c-Ki-ras2, c-Ha-ras1, c-raf1, N-myc, and c-fos. Low level expression of c-myc was detected in some lines. Southern blot experiments revealed no amplification or rearrangement of the c-Ki-ras2, N-myc or c-fos genes. Using a rapid dot-blot screening procedure, based on a combination of in-vitro amplification of ras-specific sequences and oligonucleotide hybridization, we could detect no activation of Ha-ras or Ki-ras or any unexpressed N-ras sequences secondary to a point mutation at codons 12, 13, or 61.

Blotting, Northern↗

Autoimmune thyroiditis after bone marrow transplantation.

We describe the transfer of autoimmune thyroiditis by bone marrow transplantation. The male recipient developed compensated hypothyroidism 3 years after transplantation, and progressed to thyroid failure 1 year later. The female sibling had compensated hypothyroidism when screened 4 years after marrow donation. The donor, the recipient, and an older male sibling were HLA DR4, 5; the father was presumed homozygous for DR4 and the mother for DR5. Only the donor and recipient had abnormal thyroid function and positive antithyroid antimicrosomal antibodies. The most probable mechanism for the organ specific autoimmune dysfunction is the transfer of abnormal B and T cell clones from the donor. Radiation damage to the thyroid prior to transplantation, the mild graft-versus-host disease immediately following transplantation, and the general immune dysregulation seen in the first several years after marrow engraftment may have contributed to an acceleration of the autoimmune destruction of the recipient's thyroid.

Asthma↗

Comparison of the antitumor activity of cisplatin, carboplatin, and iproplatin against established human testicular cancer cell lines in vivo and in vitro.

Cisplatin is a backbone of any combination chemotherapy currently in use for the treatment for nonseminomatous germ cell tumors. Recently new platinum analogs with lower toxicity have been developed. The antitumor activity of two analogs, carboplatin (JM8) and iproplatin (JM9) was compared to cisplatin in vitro and in vivo. The 3thymidine incorporation in three established human testicular cancer cell lines was significantly stronger inhibited by cisplatin than by JM8 or JM9. Cisplatin showed a significantly stronger antitumor activity against heterotransplanted human testicular cancer cell lines in the nude mouse than JM8 or JM9 when given at equitoxic doses. Although both analogs only moderately retarded the tumor growth, cisplatin produced a significant reduction of tumor volume in three of four cell lines. From these data it is concluded that the antitumor activity of cisplatin may be significantly superior to JM8 and JM9, and results of preclinical investigations should be awaited before replacement of cisplatin by JM8 or JM9 in the treatment of nonseminomatous germ cell tumors can be considered.

Animals↗

Characterization of rearranged Y chromosomes in human testicular tumor cell lines.

Cytogenetic analysis of four cell lines established from two different human testicular tumors revealed rearranged or missing Y chromosomes. Southern blot analysis and in situ hybridization with different Y-derived human DNA sequences revealed the existence of Y chromosomal material even in a line without a cytogenetically visible Y chromosome and clarified the composition of Y marker chromosomes.

Base Sequence↗

Intermediate-dose intravenous methotrexate and mercaptopurine therapy for non-T, non-B acute lymphocytic leukemia of childhood: a Pediatric Oncology Group study.

Methotrexate (MTX) and mercaptopurine (MP) are the mainstays of continuation therapy for acute lymphocytic leukemia (ALL). These drugs are stored in tissues as active metabolites. Relapse in ALL might reflect failure to achieve adequate intracellular drug levels. Assured (parenteral) delivery of higher doses of MTX and MP should maximize tissue levels of these drugs by overcoming individual variations in absorption, metabolism, clearance, and compliance. Fifty-nine children with ALL at lower risk of relapse received 12 intensive MTX/MP courses immediately after 4 weeks of standard vincristine, prednisone, and asparaginase induction. Each 2-week intensive course included: MTX, 200 mg/m2 intravenous (IV) push then 800 mg/m2 IV over 24 hours on day 1; MP, 200 mg/m2 IV push then 800 mg/m2 IV over 8 hours on day 2; MTX, 20 mg/m2 intramuscularly on day 8; and MP, 50 mg/m2 orally daily on days 8 to 14. After the 6 months of intensive therapy, continuation therapy was weekly MTX/MP (as on days 8 to 14) for 1 or 2 years. Age-based MTX was given intrathecally (IT) for CNS prophylaxis. All patients entered remission. Three patients relapsed: bone marrow (at 24 and 37 months), and bone marrow and CNS (at 34 months). There were no isolated CNS relapses or deaths in remission. Event-free survival at 4 years is 94% (SE, 7%) by Kaplan-Meier analysis. Toxicities (infection, mucositis) occurred in less than 10% of intensive MTX/MP courses. However, a child with Down's syndrome withdrew after three courses because of recurrent severe mucositis. Further studies of this regimen are in progress.

Antineoplastic Combined Chemotherapy Protocols↗

Bone marrow transplantation for children with severe aplastic anemia: use of donors other than HLA-identical siblings.

Eighty-five percent of untransfused and 70% of transfused patients with severe aplastic anemia (SAA) are cured with bone marrow transplants from histocompatible sibling donors. Use of partially matched family donors or unrelated donors has been relatively unsuccessful because of high incidences of graft rejection and graft-versus-host disease (GVHD). Thirteen children with SAA received marrow grafts from alternative donors (sibling 4, parent 5, unrelated 4). The first three patients were pretreated with cyclophosphamide (CYCLO) +/- irradiation and received methotrexate for GVHD prophylaxis. Subsequent children were pretreated with CYCLO + high-dose cytosine arabinoside + methylprednisolone + total body irradiation, had monoclonal antibody T-cell depletion of the donor marrow, and received cyclosporine for GVHD prophylaxis. Three heavily transfused patients with haploidentical-related donors failed to engraft and died. All 10 patients with more closely matched donors engrafted. Acute GVHD was grade II in only one patient (non-T-depleted); this patient is the only one with severe chronic GVHD. Three engrafted patients died (Pneumocystis pneumonia, systemic parainfluenza, venocclusive disease). Seven children are alive 33+ to 2,692+ days. Donors for the survivors were siblings 3, parent 1, unrelated 3. These data suggest that bone marrow transplantation from closely matched donors other than histocompatible siblings can be effective therapy for SAA if an intensive conditioning regimen is used. These results must be confirmed with larger numbers and longer follow-up.

Adolescent↗

Intravenous immunoglobulin may lessen all forms of infection in patients receiving allogeneic bone marrow transplantation for acute lymphoblastic leukemia: a pediatric oncology group study.

Fifty patients with refractory acute lymphoblastic leukemia underwent allogeneic bone marrow transplantation after conditioning with high-dose cytosine arabinoside and fractionated total body irradiation. Twenty-nine received intravenous immunoglobulin (i.v.Ig) infusion, primarily to prevent cytomegalovirus infection, and 21 did not. The two groups were biologically comparable. Seven (24.5%) of the i.v.Ig-treated and 14 (66.7%) of the non-i.v.Ig-treated patients developed systemic viral, fungal or bacterial infections and/or interstitial pneumonitis (p less than 0.005), which were fatal in three and 12 cases respectively (p less than 0.001). Currently, 23 (79.3%) of the 29 i.v.Ig-treated and eight (38.1%) of the 21 non-i.v.Ig-treated patients are alive and well (p less than 0.01). We conclude that prophylactic i.v.Ig infusions may reduce the frequency of all forms of serious infection in patients with acute lymphoblastic leukemia undergoing allogeneic marrow transplantation, and thereby improve their survival expectation.

Bone Marrow Transplantation↗

Cell lines of human germinal cancer.

Three new established human germ cell tumour lines, H 12.1, H 12.5 and H 12.7, are described. Cytogenetic and growth characteristics, morphology, histology, and tumour marker and steroid hormone production in vitro and/or in vivo revealed properties commonly found in other germ cell tumour lines and in patients with these tumours. In vitro oestrone and oestradiol were produced by the H 12 lines and four other lines (833 KE, 1156 Q, 1428 A and 2102 EP) under high and low density (differentiation inducing) conditions. AFP was produced by one line and beta-hCG by six of seven lines under low density conditions. The pattern of oestrogen production suggests that these hormones could be useful in AFP and beta-hCG negative patients. Differentiated elements of somatic and extraembryonic character, observed in tumours of H 12.1 and H 12.7, underline the value of these lines in the study of differentiation and other germ cell tumour related questions.

Animals↗

Comparative antitumour activity of cisplatin and two new cisplatin-analogues JM8 and JM9 in human testicular carcinoma xenografts.

The comparative antitumour activity of cisplatin, JM8 and JM9 was tested using a panel of different heterotransplanted human testicular tumour cell lines. All drugs were applied at equitoxic doses in a 5 day schedule. In the two cisplatin sensitive cell lines 2102 EP and H 12.1 both analogues were inferior to cisplatin. No significant therapeutic effect was achieved with any of the three drugs in the cisplatin resistant line H 23.1. Thus JM8 and JM9 seem to be less active in cisplatin sensitive tumours and seem to be of no advantage in the case of cisplatin resistance.

Animals↗

Comparison of endogenous lectins in human embryonic carcinoma and yolk sac carcinoma.

Salt and detergent extracts of xenografted human embryonic carcinoma and a human yolk sac carcinoma were fractionated on different sets of Sepharose columns covalently derivatized with lactose, asialofetuin, melibiose, mannan and fucose. Successive elution by chelating reagent and specific sugar resulted in isolation of endogenous Ca2+-dependent and Ca2+-independent carbohydrate-binding proteins, as analyzed by gel electrophoresis. The salt extracts of the embryonic carcinoma contained a Ca2+-dependent carbohydrate-binding protein at Mr66,000, that was undetectable in yolk sac tumor extracts. Also, a Ca2+-independent fucose-binding protein at Mr62,000 could be purified. In general, the pattern of carbohydrate-binding proteins showed quantitative and qualitative differences as compared to normal tissue. The carbohydrate-binding proteins were assayable as agglutinin and showed no enzymatic activity. They can thus be defined as lectins. Their presence within certain stages of differentiation and developmental regulation may contribute to improvement of the classification, diagnosis and therapy of this tumor class. These new lectins may also be functionally related to the stage-specific embryonic antigens like SSEA-1.

Adult↗

Nonrandom chromosome alterations in rhabdomyosarcoma.

Chromosome banding analysis was attempted on tumor cells from a total of six rhabdomyosarcomas. Results revealed a variety of chromosome alterations, including frequent structural rearrangement of chromosome #1 and the finding in one patient of multiple double minutes. The single chromosome most consistently involved in structural rearrangements was #3. Simple deletion or translocation of either the long or short arm of chromosome #3 was found in all rhabdomyosarcoma tumors examined in this report. Further, a review of the limited previous literature on rhabdomyosarcoma provided further support for the frequent alteration of chromosome #3 in this disease. Results from our study provide preliminary evidence that alterations of chromosome 3p14-21 may represent a site of nonrandom chromosome change in rhabdomyosarcoma.

Chromosome Aberrations↗

Disorders of speech and voice.

The focus of this article has been on the disorders of the motor aspects of speech and voice production, as contrasted with the symbolic aspects of the communication process (language). Categories of motor speech problems include those in which the articulation of speech sounds is aberrant, phonatory problems related to laryngeal function, those resulting from craniofacial anomalies, and finally those characterized by disruption in the flow or fluency of speech. Guidelines for timing and type of referral have been suggested. In each case, early referral is urged so that diagnosis of the problem based upon complete assessment can serve to guide treatment planning. Parental reports and concerns about a child's speech development (as well as language, cognitive and auditory behavior) should be given credence and attended to rather than ignored or postponed. Speech disorders are often amenable to total resolution and almost always to a significant degree of improvement, especially if diagnosed and treated early.

Adolescent↗

Cell surface lectins of transplantable human teratocarcinoma cells: purification of a new mannan-specific endogenous lectin.

Fractionation of detergent extracts of transplanted tumors of human teratocarcinoma cells by affinity chromatography yields one predominant protein with apparent molecular weight of 14,000 and further, for less abundant protein with apparent molecular weight of 35,000 from lactose-sepharose and one protein with apparent molecular weight of 68,000 from mannan-sepharose. No further carbohydrate-binding protein can be isolated on columns derivatized with asialofetuin, melibiose and L-fucose, to which the extract is applied successively. Both proteins agglutinate trypsinized, glutaraldehyde-fixed rabbit erythrocytes in the absence of Ca2+ and can thus be defined as endogenous human teratocarcinoma lectins. Inhibition of heterotypic and homotypic aggregation of human teratocarcinoma cells by D-mannose, D-galactose and glycoproteins rich in one of these sugars is consistent with a functional role of these Ca2+-independent lectins in cell aggregation. Visualization of these activities by fluorescent mannosylated and lactosylated markers on the cell surface further supports the cell surface localization of these detergent extractable lectins. The mannan-specific lectin, in particular, has so far not been detected in any mammalian tissue or tumor and is of potential value for a lectin-based diagnosis and therapy of embryonal carcinomas.

Carbohydrates↗