Isolation and sequence of a full length cDNA encoding a novel rat inositol 1,4,5-trisphosphate 3-kinase

Immunoscreening a rat liver cDNA expression library has led to the isolation of a full-length cDNA clone encoding a novel isoform of rat inositol 1,4,5-trisphosphate 3-kinase (IP3 3-kinase). Sequence comparison shows it (i) to be 93% identical to human hippocampus IP3 3-kinase B over 468 residues at the protein level, and (ii) to encode a protein 204 amino acids larger than the published sequence of its human homologue.

The inter-relationship between insulin and chromium in hyperinsulinaemic euglycaemic clamps in healthy volunteers

Evidence in the literature suggests that the trace element chromium may have a role in glucose homeostasis through the regulation of insulin action. We have previously reported a significant reduction in plasma chromium levels in healthy individuals, following a 75 g oral glucose load, and after meals and glucose-dependent uptake of chromium in insulin-dependent tissues in vitro. However, in vivo it is unclear whether the changes in plasma chromium relate to changes in plasma glucose or insulin. The present study describes a series of euglycaemic hyperinsulinaemic clamps designed to attempt to define the initiator of changes in plasma chromium levels in ten healthy individuals. The data showed a significant (P < 0.01) reduction in fasting plasma chromium levels following glucose infusion and an initial bolus of insulin. Significant (P < 0.02) increases in post-clamp urinary chromium excretion were insufficient to explain the decrease in plasma levels. During the recovery phase of an extended two-phase clamp protocol we found plasma insulin levels decreased by 70% within 10 min, associated with an increase in plasma chromium levels of 30% and no significant change in plasma glucose level. These data indicate that alterations in plasma glucose are unlikely to be directly related to changes in plasma chromium, whilst supporting the hypothesis that plasma insulin may influence plasma levels of this trace element. In contrast, plasma zinc was unaffected throughout these clamp studies.

Clinical research units for the treatment of patients with HIV disease: operational issues and components needed to conduct clinical trials

Clinical trials are of paramount importance for the development and evaluation of new therapies for patients with human immunodeficiency virus (HIV) disease. The objective of an HIV clinical research unit is to conduct high quality clinical research with patients who have HIV disease. The conduct of these research studies requires accurate and complete data collection. Coordination of the patients' primary care must be complemented by a working knowledge of the relevant ethical issues. In addition, technical, managerial, and clinical expertise is needed for conducting the trials and collecting data. To accurately plan the research, personnel and resource allocation should be periodically assessed. Clinicians, particularly those who have not previously conducted clinical trials or who are considering the incorporation of a research program into a primary care setting, must be familiar with these issues in order to create and supervise this type of clinical research unit. A smoothly running clinic observing a defined cohort of patients is attractive to government agencies and pharmaceutical sponsors for funding of clinical trials and research projects.

Mutational removal of the major site of serine phosphorylation of the epidermal growth factor receptor causes potentiation of signal transduction: role of receptor down-regulation

The major site of epidermal growth factor receptor (EGF-R) serine phosphorylation is located within the COOH-terminal domain of the receptor at Ser1046/7. We have previously demonstrated that this phosphorylation site accounts for the acute desensitization of the EGF-R observed in EGF-treated cells. Here we show that the mutational removal of this negative regulatory phosphorylation site causes potentiation of signal transduction by the EGF-R. This potentiation can be accounted for in part by a block in the EGF-stimulated down-regulation of the EGF-R. These data indicate that the SER1046/7 phosphorylation site may have a regulatory role during long term incubation of cells with mitogenic concentrations of EGF.

Signal transduction by the epidermal growth factor receptor is attenuated by a COOH-terminal domain serine phosphorylation site

It has been proposed that the acute desensitization of epidermal growth factor receptor (EGF-R) function can be accounted for, in part, by the effect of EGF to increase phosphorylation of the receptor at Ser1046/7 (Countaway, J.L., Nairn, A.C., and Davis, R.J. (1992) J. Biol. Chem. 267, 1129-1140). Here, we show that the mutational removal of this phosphorylation site causes an activation of EGF-R function and a potentiation of signal transduction. The mechanism of potentiation results from 1) defective down-regulation of the EGF-R when cells are incubated with high concentrations of EGF; and 2) increased EGF-stimulated tyrosine phosphorylation. The increased EGF-stimulated phosphorylation is associated with an alteration of the apparent specificity of tyrosine phosphorylation and is independent of the down-regulation defect. Together, these data strongly support the hypothesis that Ser1046/7 is a biologically significant site of regulatory phosphorylation of the EGF-R.

Effect of hysterectomy on anorectal and urethrovesical physiology

To investigate whether vaginal or total abdominal hysterectomy is associated with changes in anorectal and urethrovesical physiology, 26 women were studied before operation and six weeks and six months afterwards. The results showed a postoperative increase in both rectal and vesical sensitivity (p less than 0.01). Similar results were observed irrespective of the type of hysterectomy. No significant changes in rectal or bladder compliance were noted, and anal pressure and urethral pressure and length were unchanged after surgery. Whole gut transit was not affected by hysterectomy. Urinary symptoms occurred de novo in 6/26 women and gastrointestinal symptoms in 2/26 women. These results show that significant changes in rectal and vesical sensitivity occur after hysterectomy for benign disease. These persist for at least six months postoperatively but are not always associated with development of urinary or gastrointestinal symptoms.

Constitutive phosphorylation of the epidermal growth factor receptor blocks mitogenic signal transduction

The epidermal growth factor (EGF) receptor is phosphorylated by protein kinase C at Thr654. It has been proposed that the phosphorylation of this site is an important regulatory mechanism for the control of EGF receptor function. However, the physiological significance of the phosphorylation of EGF receptor Thr654 in intact cells is not understood. To address this question, the design of an experimental strategy is required that can be used to distinguish between the pleiotropic effects of kinase C activation and the specific effects of kinase C that are mediated by the phosphorylation of the EGF receptor at Thr654. The approach that we used was to examine the function of EGF receptors that are constitutively phosphorylated at residue 654. It was observed that the constitutive phosphorylation of the EGF receptor blocked mitogenic signal transduction by the receptor. These data are consistent with the hypothesis that the phosphorylation of the EGF receptor at residue 654 in intact cells inhibits EGF-stimulated cellular proliferation.

Role changes at the pharmacy-nursing interface: Kimball Medical Center

The original goals and objectives of the CST program have been realized. Medication safety, control, accountability, and utilization efforts of decentralized satellite pharmacists have been brought to fruition. A career ladder has been created for the pharmacy technician. This has enabled the Department of Pharmaceutical Services to recruit, retain, and develop an exceptionally competent and proficient technical staff. The pharmacy has earned a new found respect from the nursing division. A greater awareness of its staff's positions as drug experts and information resources has evolved. Credibility has been established for additional pharmacy programs and proposed clinical activities. Pharmacists and technicians have gained an in-depth understanding of the procedures, problems, and challenges of the nursing services, which has enabled a bridge of understanding and a common bond of team effort to be built between the two departments.

The 68 kDa protein of signal recognition particle contains a glycine-rich region also found in certain RNA-binding proteins

Signal recognition particle (SRP) interacts with the signal sequence in nascent secretory and membrane proteins and directs them to the membrane of the endoplasmic reticulum. Membrane targeting is mediated by the 68 and the 72 kDa proteins of SRP. We have cloned and sequenced cDNA encoding the 68 kDa protein of canine signal recognition particle (SRP68). SRP68 is a basic protein comprised of 622 amino acid residues. Close to the amino terminus there is a glycine-rich region which SRP68 has in common with some RNA-binding proteins. SRP68 shares no detectable similarity to any of the proteins in data libraries.

The control of breast cancer. A World Health Organization perspective

The greatest decrease in breast cancer mortality is likely to derive from applying globally existing therapies at an earlier stage. A high priority of the World Health Organization (WHO) cancer control program is the outreach approach that promotes worldwide access to cancer therapies of proven values. Therefore, the first priority in national health programs for breast cancer is to encourage patients to present for diagnosis and treatment at an earlier stage of the disease. In the development of guidelines for the early detection of breast cancer, the WHO emphasizes the importance of appropriate widespread coverage of high-risk groups as opposed to repetitive screening of low-risk groups, so that early detection will be effective. A WHO/USSR controlled trial of breast self-examination and community-based adjuvant therapy is helping to develop the WHO global recommendations for the control of breast cancer. Depending on the extent of the breast cancer problem, the local resources, and the cultural situation, national health strategies should include all three main elements--public education, early detection, locally available treatment, or a combination of these to a national comprehensive program for the control of breast cancer.

Membrane-anchored and soluble forms of betaglycan, a polymorphic proteoglycan that binds transforming growth factor-beta

Transforming growth factors beta 1 and beta 2 bind with high affinity to the core protein of a 250-350-kD cell surface proteoglycan. This proteoglycan (formerly referred to as the type III TGF-beta receptor) coexists in many cells with the receptor implicated in TGF-beta signal transduction (type I TGF-beta receptor), but its function is not known. We report here that soluble TGF-beta-binding proteoglycans are released by several cell types into the culture media, and can be found in serum and extracellular matrices. As has been shown for the membrane-bound form, the soluble proteoglycans have a heterogeneous core protein of 100-120 kD that carries chondroitin sulfate and/or heparan sulfate glycosaminoglycan chains and a small amount of N-linked carbohydrate. The membrane-bound form of this proteoglycan is hydrophobic and associates with liposomes, whereas the soluble forms lack a membrane anchor and do not associate with liposomes. Differences in the electrophoretic migration of the soluble and membrane forms of this proteoglycan suggest additional structural differences in their core proteins and glycosaminoglycan chains. These soluble and membrane-bound proteoglycans, for which we propose the name "betaglycans," might play distinct roles in pericellular retention, delivery, or clearance of activated TGF-beta.

The gene for human complement C9 is on chromosome 5

By hybridizing a cloned cDNA coding for human complement factor C9 to hybrid cells containing subsets of human chromosomes on a rodent background, we have determined that the human gene for C9 is localized on chromosome 5.

The gene for the human putative apoE receptor is on chromosome 12 in the segment q13-14

We have previously described the cDNA coding for a new lipoprotein receptor that contains domains closely related to the ligand-binding domain of the LDL receptor. We have now investigated the localization of the gene for this new receptor by hybridization of the cDNA to panels of rodent cells containing subsets of human chromosomes and by in situ hybridization of the cDNA to chromosomes. The gene maps to 12q13-14, a known hot spot for chromosomal rearrangements in human neoplasia. Of particular interest is the frequent involvement of the 12q13-14 segment in clonal abnormalities in lipomas and myxoid liposarcomas, and it is possible that LRP may play a role in the pathogenesis of such tumors.

Heterodimeric transforming growth factor beta. Biological properties and interaction with three types of cell surface receptors

Type beta transforming growth factors (TGF) are disulfide-linked homo- and heterodimers of two related polypeptide chains, beta 1 and beta 2. The homodimers TGF-beta 1 and TGF-beta 2 are widely distributed, but the heterodimer TGF-beta 1.2 has been found only in porcine platelets (Cheifetz, S., Weatherbee, J.A., Tsang, M.L.-S., Anderson, J.K., Mole, J.E., Lucas, R., and Massagué, J. (1987) Cell 48, 409-415). Here we characterize the receptor binding and biological properties of TGF-beta 1.2 and compare them with those of TGF-beta 1 and TGF-beta 2. Three types of cell surface receptors previously identified by affinity labeling with 125I-TGF-beta 1 are available for binding to TGF-beta 1.2. These three types of receptors are detected as 65-kDa (type I), 85-95-kDa (type II), and 250-350-kDa (type III) affinity-labeled receptor complexes on electrophoresis gels. They co-exist in many cell types, have high affinity for TGF-beta 1, and varying degrees of affinity for TGF-beta 2. Of the 11 cell lines screened in the present study none showed evidence for additional receptor types that would bind TGF-beta 2 but not TGF-beta 1. In receptor competition studies, TGF-beta 1, TGF-beta 1.2, and TGF-beta 2 competed for binding to type I and type II receptors with a relative order of potencies of 16:5:1 and 12:3:1, respectively, whereas all three forms of TGF-beta were equipotent as ligands for the type III receptors. The three forms of TGF-beta were equally potent at stimulating the biosynthesis of extracellular sulfated proteoglycan in BRL-3A rat liver epithelial cells, a response that presumably involves the type III receptor present in these cells. In contrast, the ability of the three ligands to inhibit the growth of B6SUt-A multipotential hematopoietic progenitor cells which display only type I receptors decreased in the order TGF-beta 1, TGF-beta 1.2, and TGF-beta 2 with a relative potency of 100:30:1. The results indicate that the presence of one beta 1 chain in TGF-beta 1.2 increases (with respect to TGF-beta 2) the biological potency and binding affinity toward receptor types I and II, but the presence of a second beta 1 chain in the dimer is required for full potency.

Bladder cancer: approaches to prevention and control

Bladder cancer is the twelfth most common cancer globally, with approximately 170 000 new cases each year; a third of these cases are in the developing countries. There are two major etiological types. The first is more common in the industrialized countries and is associated with exposure to certain occupational and environmental carcinogens, but most importantly with tobacco smoking. The second type is associated with Schistosoma haematobium infection of the urinary tract and is one of the most frequent tumours in eastern Mediterranean and African countries. Both types of bladder cancer are largely preventable. Comprehensive education and legislative approaches are recommended to reduce tobacco consumption and exposure to industrial carcinogens. Safe and effective drugs are available to treat schistosomiasis within integrated control programmes in endemic areas.

Cancer control: introduction to a series of reports on strategies and approaches

No search for new treatments of cancer or new preventive measures can realistically hope to offer benefits anywhere near as large as those that can be gained by the wider application of current knowledge. A series of papers on strategies in cancer control, to be published in the Bulletin of the World Health Organization, will describe the foundations and approaches that can significantly reduce morbidity and mortality from cancer.

A human cell-surface antigen defined by a monoclonal antibody and controlled by a gene on human chromosome 1

An antigen expressed by most human cells, but not erythrocytes, has been defined by a murine monoclonal antibody, TRA-2-10. This antigen is expressed on the surface of human-mouse somatic cell hybrids, and segregation analysis indicates that it is controlled by a gene located on human chromosome 1. From lysates of most human cells, surface-labelled with 125I, TRA-2-10 immunoprecipitates two polypeptides with molecular weights in the range of about 55 000 to 73 000 depending upon the cell line. Since the TRA-2-10 polypeptides from a fibroblast cell strain and a hepatoma cell line from one individual differ, we conclude that the observed difference in molecular weight has an epigenetic origin.

Chromosome mapping of cell membrane antigens expressed on activated B cells

Hybrids formed by fusion of either human acute lymphoblastic or chronic lymphocytic leukemia cells and the mouse myeloma P3.X63.Ag8/653 have been used to show that the expression of two cell surface antigens, Bp37 and p76, associated with B cell activation and detected by the monoclonal antibodies BB1 and BB2, respectively, segregate with human chromosomes 12 and 19, respectively. Another antigen expressed on activated B cells (p24) also maps to chromosome 12 (Katz et al., Eur. J. Immunol. 1984. 13: 1008) which is of interest in the light of the frequent involvement of this chromosome in certain B cell leukemias and lymphomas.

Chromosome assignment of monoclonal antibody-defined determinants on human leukemic cells

Hybrids formed between human acute lymphoblastic leukemia (ALL) cells and mouse myeloma have been used to determine the chromosomal location of genes required for the expression of several monoclonal antibody (mAb)-defined cell surface antigens on ALL cells. Cloned hybrids were tested for antibody binding, immunoprecipitation of the relevant protein, chromosome isoenzyme markers and karyotype. Two antigens of those studies could be definitively mapped, OKT10/p45 to chromosome 4 and BA-2/p24 to chromosome 12. mAb BA-2 reacts with the same protein as another mAb designated 609-29 (anti-teratocarcinoma). Reactivity with the latter mAb has been previously shown to segregate with chromosome 12.

A monoclonal antibody to the heavy chain of clathrin

Monoclonal antibodies have been raised to pig brain triskelions and one clone, DC41, was found to recognize the clathrin heavy chain by immunoblotting. However, both by immunofluorescence and immunoelectron microscopy, and in complete contrast to polyclonal anti-clathrin antibodies, monoclonal DC41 did not label either coated pits or coated vesicles anywhere in the cell. Instead it appeared to label the cell cytoplasm. These data suggest that DC41 recognizes a cytoplasmic form of clathrin, perhaps that form produced by uncoating of coated vesicles which is then ready to re-build another coated pit.

Integration of Ecogpt and SV40 early region sequences into human chromosome 17: a dominant selection system in whole cell and microcell human-mouse hybrids

The dominant selectable gene, Ecogpt, has been introduced, by the calcium phosphate precipitation technique, into normal human fibroblasts, along with the SV40 early region genes. In one transfectant clone, integration of these sequences into human chromosome 17 was demonstrated by the construction of human-mouse somatic cell hybrids, selected for by growth in medium containing mycophenolic acid and xanthine. A whole cell hybrid, made between the human transfectant and a mouse L cell, was used as donor of the Ecogpt-carrying human chromosome 17 to 'tribrids' growing in suspension, made by whole cell fusion between a mouse thymoma cell line, and to microcell hybrids made with a mouse teratocarcinoma cell line. Two tribrids contained karyotypically normal human chromosomes 17 and a small number of other human chromosomes, while a third tribrid had a portion of the long arm of chromosome 17 translocated to mouse as its only human genetic material. Two independent microcell hybrids contained a normal chromosome 17 and no other human chromosome on a mouse teratocarcinoma background. These experiments demonstrate the ability to construct human-mouse somatic cell hybrids using a dominant selection system. By applying this approach it should be possible to select for a wide range of different human chromosomes in whole cell and microcell hybrids. In particular, transfer of single human chromosomes to mouse teratocarcinoma cells will allow examination of developmentally regulated human gene sequences after differentiation of such hybrids.

Comparison of chemotherapy alone versus chemotherapy and radiation therapy of extensive small cell carcinoma of the lung

In a randomized study 145 patients with extensive small cell carcinoma of the lung were treated with chemotherapy alone (Cytoxan, CCNU, methotrexate) or with the same drug regimen and with radiation therapy to the brain, chest, and abdomen. One hundred eighteen of these patients were evaluable. Those patients receiving radiation had a better response rate (55% vs 31%, P = .016) but significantly greater toxicity. There was no significant difference in rates of complete response (7% vs 8%) or in survival (median 18.4 vs 15.3 weeks) between the two groups overall. The median survival of those patients with a partial response to therapy was 18 weeks; for those achieving a complete response it was 46 weeks. However, a clear difference in survival comparing responders with non-responders was evident only for patients who were assigned to chemotherapy alone. Partial regressions have little, if any, correlation with improvement in survival. Therapy in this disease must be oriented toward inducing complete response.

Phase II study of cisplatin, maytansine, and chlorozotocin in small cell lung carcinoma (EST 2578)

Seventy-three patients with small cell lung carcinoma refractory to standard chemotherapy were entered in this phase II randomized study of cisplatin, maytansine, and chlorozotocin. Of the 58 evaluable patients, only one partial response was observed among 21 patients given cisplatin, and no responses were seen among 19 given maytansine or 18 given chlorozotocin. One patient treated with chlorozotocin and two treated with cisplatin experienced life-threatening thrombocytopenia. One third of the maytansine-treated patients experienced moderate or severe neurologic toxicity. The overall median survival was 9.7 weeks. Chlorozotocin treatment was associated with inferior survival (7.7 weeks).

Radiotherapy in the management of locally advanced lung cancer of all cell types: final report of randomized trial

Between 1975 and 1978, 343 evaluable male patients with a diagnosis of locally advanced lung cancer of all cell types were entered in Protocol 15. The patients had unresectable or inoperable tumor limited to one hemithorax and no evidence of distant metastases. The cell-type distribution was as follows: squamous cell carcinoma (Sq CC) 137 (40%); positive cytology 66 (19%); large cell carcinoma 57 (17%); small cell carcinoma (SCC) 46 (13%) and adenocarcinoma 37 (11%). An intermediate course of irradiation (ICI) of 5000 rads in 25 fractions, 200 rads each, in 5 weeks was compared with a short course of irradiation (SCI) of 4200 rads in 15 fractions, 280 rads each, in 3 weeks (equal Nominal Standard Dose). The effectiveness of low dose irradiation to control subclinical brain metastases was studied and was reported separately. The median survival for all 343 patients was 38 weeks. There was no significant difference in survival, response and control rate between the 191 ICI and the 152 SCI patients. The following factors had a significant individual influence on survival: initial performance status, ambulatory vs. nonambulatory, P = 0.006; histology, Sq CC vs. other cell types (OCT), P = 0.0007; prior surgery, less than 6 weeks vs. greater than 6 weeks, p = 0.04; tumor size, diameter less than 6 cm vs. greater than 6 cm, P = 0.05 and weight loss less than 5% vs. greater than 5% in the previous 6 months, P = 0.01. The overall response rate (CR or PR) was 38%. The median duration of response was shorter for the ICI group when compared with the SCI group, 18.4 vs. 34.4 weeks, P = 0.02. The presence of partial or complete response enhanced the median survival 50 vs. 31 weeks. Cell type, Sq CC vs. OCT was an important factor for the duration of response, 49 vs. 21 weeks, P = 0.0006. The complication rate was similar for the 191 ICI patients when compared with the 152 SCI patients. There were however, two patients with radiation myelopathy among the SCI patients and none among the ICI patients.

Cranial irradiation in cancer of the lung of all cell types

The Veterans Administration Lung Group conducted a prospective study of irradiation for subclinical brain metastases in patients with inoperable carcinoma of the lung between 1975 and 1978. Patients were randomized to receive whole-brain irradiation (2,000 rads in two weeks) or no brain treatment, and to receive one of two regimens of thoracic irradiation. Three hundred twenty-three patients with normal radionuclide brain scans were able to be evaluated. The rate of clinical brain metastasis was 26% for patients with small cell carcinoma vs 10% for the "non-small-cell" group. A statistically insignificant decrease in the rate of brain metastasis was found among irradiated patients with small cell carcinoma. The frequency of brain metastasis in the non-small-cell patients was reduced from 13% to 6% by irradiation. Prophylactic cranial irradiation can decrease morbidity from non-small-cell carcinoma of the lung.

A statistical analysis of murine stem cell suicide techniques

The clinical application of soft agar cloning techniques for granulocyte-macrophage stem cells (CFU-C) has resulted in a number of contradictory reports that may in part be due to an inadequate data base. Growth of murine CFU-C is more reproducible and less variable than that of human CFU-C. We utilized in vivo hydroxyurea suicide of murine marrow CFU-C to address the question of how many experiments are needed to detect a specific difference with a p of less than 0.05. In 66 experiments the mean marrow CFU-C hydroxyurea kill was 23.3%; 6-9 separate experiments were necessary to detaect differences of 25%-30%. In order to be sure that a 25%-30% difference is not present, 15-21 experiments were required. Using a Dec-20 computer, 1000 samples of sample size 3, 4, or 10 were drawn from the 66 experiments; it was found that with 3 experiments and a true value of 23%, the actually observed value was below 10%, 17% of the time, and was over 40% in 10% of the samplings. In a smaller number of experiments similar results were obtained analyzing 3HTdR suicide of pluripotent stem cells and CFU-C. These data could provide a base from which to judge the validity of studies utilizing the CFU-C technique.

Evaluation of sternal bone marrow aspiration for detection of tumor cells in patients with bronchogenic carcinoma

We evaluated sternal bone marrow aspiration as a routine pretreatment procedure in patients with bronchogenic carcinoma. The overall rate of identification of tumor cells by this technique was found to be low. When oat cell bronchogenic carcinoma was considered as a separate entity, the positive rate was higher. However, in no instance did the bone marrow aspiration result in a change in clinical staging.