Showing papers by "Fred Hutchinson Cancer Research Center published in 1987"

Asymptotic Properties of Maximum Likelihood Estimators and Likelihood Ratio Tests under Nonstandard Conditions

Abstract: Large sample properties of the likelihood function when the true parameter value may be on the boundary of the parameter space are described. Specifically, the asymptotic distribution of maximum likelihood estimators and likelihood ratio statistics are derived. These results generalize the work of Moran (1971), Chant (1974), and Chernoff (1954). Some of Chant's results are shown to be incorrect. The approach used in deriving these results follows from comments made by Moran and Chant. The problem is shown to be asymptotically equivalent to the problem of estimating the restricted mean of a multivariate Gaussian distribution from a sample of size 1. In this representation the Gaussian random variable corresponds to the limit of the normalized score statistic and the estimate of the mean corresponds to the limit of the normalized maximum likelihood estimator. Thus the limiting distribution of the maximum likelihood estimator is the same as the distribution of the projection of the Gaussian random v...

Identification of multiple cell adhesion receptors for collagen and fibronectin in human fibrosarcoma cells possessing unique alpha and common beta subunits.

Abstract: Using monoclonal antibody technology and affinity chromatography we have identified four distinct classes of cell surface receptors for native collagen on a cultured human fibrosarcoma cell line, HT-1080. Two classes of monoclonal antibodies prepared against HT-1080 cells inhibited adhesion to extracellular matrix components. Class I antibodies inhibited cell adhesion to collagen, fibronectin, and laminin. These antibodies immunoprecipitated two noncovalently linked proteins (subunits) with molecular masses of 147 and 125 kD, termed alpha and beta, respectively. Class II antibodies inhibited cell adhesion to native collagen only and not fibronectin or laminin. Class II antibodies immunoprecipitated a single cell surface protein containing two noncovalently linked subunits with molecular masses of 145 and 125 kD, termed alpha and beta, respectively. The two classes of antibodies did not cross-react with the same cell surface protein and recognized epitopes present on the alpha subunits. Pulse-chase labeling studies with [35S]methionine indicated that neither class I nor II antigen was a metabolic precursor of the other. Comparison of the alpha and beta subunits of the class I and II antigens by peptide mapping indicated that the beta subunits were identical while the alpha subunits were distinct. In affinity chromatography experiments HT-1080 cells were extracted with Triton X-100 or octylglucoside detergents and chromatographed on insoluble fibronectin or native type I or VI collagens. A single membrane protein with the biochemical characteristics of the class I antigen was isolated on fibronectin-Sepharose and could be immunoprecipitated with the class I monoclonal antibody. The class I antigen also specifically bound to type I and VI collagens, consistent with the observation that the class I antibodies inhibit cell adhesion to types VI and I collagen and fibronectin. The class II antigen, however, did not bind to collagen (or fibronectin) even though class II monoclonal antibodies completely inhibited adhesion of HT-1080 cells to types I and III-VI collagen. The class I beta and II beta subunits were structurally related to the beta subunit of the fibronectin receptor described by others. However, none of these receptors shared the same alpha subunits. Additional membrane glycoprotein(s) with molecular mass ranges of 80-90 and 35-45 kD, termed the class III and IV receptors, respectively, bound to types I and VI collagen but not to fibronectin. Monoclonal antibodies prepared against the class III receptor had no consistent effect on cell attachment or spreading, suggesting that it is not directly involved in adhesion to collagen-coated substrates.(ABSTRACT TRUNCATED AT 400 WORDS)

Sexual practices, sexually transmitted diseases, and the incidence of anal cancer.

Abstract: To elucidate the risk factors for anal cancer, we interviewed and obtained blood specimens from 148 persons with anal cancer and from 166 controls with colon cancer in whom these diseases were diagnosed during 1978-1985. We found that in men, a history of receptive anal intercourse (related to homosexual behavior) was strongly associated with the occurrence of anal cancer (relative risk, 33.1; 95 percent confidence interval, 4.0 to 272.1). Anal intercourse was only weakly associated with the risk of anal cancer in women (relative risk, 1.8; 95 percent confidence interval, 0.7 to 4.2). Among the subjects with squamous-cell anal cancer, 47.1 percent of homosexual men, 28.6 percent of heterosexual men, and 28.3 percent of women gave a history of genital warts, as compared with only 1 to 2 percent of controls and no patients with transitional-cell anal cancer. In patients without a history of warts, anal cancer was associated with a history of gonorrhea in heterosexual men (relative risk, 17.2; 95 percent confidence interval, 2.0 to 149.4) and with seropositivity for herpes simplex type 2 (relative risk, 4.1; 95 percent confidence interval, 1.9 to 8.8) and Chlamydia trachomatis (relative risk, 2.3; 95 percent confidence interval, 1.1 to 4.8) in women. Current cigarette smoking was a substantial risk factor in both women (relative risk, 7.7; 95 percent confidence interval, 3.5 to 17.2) and men (relative risk, 9.4; 95 percent confidence interval, 2.3 to 38.5). We conclude that homosexual behavior in men is a risk factor for anal cancer, and that squamous-cell anal cancer is also associated with a history of genital warts, an association suggesting that papillomavirus infection is a cause of anal cancer. Certain other genital infections and cigarette smoking are also associated with anal cancer.

Evidence that the packaging signal of Moloney murine leukemia virus extends into the gag region.

Abstract: Replication-competent retroviruses can be modified to carry nonviral genes. Such gene transfer vectors help define regions of the retroviral genome that are required in cis for retroviral replication. Moloney murine leukemia virus has been used extensively in vector construction, and all of the internal protein-encoding regions can be removed and replaced with other genes while still allowing production of virions containing and transmitting the altered retroviral genome. However, inclusion of a portion of the gag region from Moloney murine leukemia virus markedly increases the titer of virus derived from these vectors. We determined that this effect was due to more efficient packaging of the vector RNA into particles and did not depend on protein synthesis from the gag region. We conclude that the retrovirus packaging signal extends into the gag region. We have found that retroviral vectors containing the complete packaging signal allow more efficient gene transfer into a variety of cell types. In addition, these results may help explain why many oncogenic retroviruses have retained gag sequences and often express transforming proteins that are gag-onc hybrids.

A 17-kD centromere protein (CENP-A) copurifies with nucleosome core particles and with histones

Abstract: We have detected and begun to characterize a 17-kD centromere-specific protein, CENP-A (Earnshaw, W. C., and N. Rothfield, 1985, Chromosoma., 91:313-321). Sera from several humans with CREST scleroderma autoimmune disease (CREST: calcinosis, Raynaud's phenomenon, esophageal dsymotility, sclerodactyly, and telangiectasia) bind this protein in immunoblot assays of HeLa whole cell or nuclear extracts. We have affinity purified the anti-17-kD centromere protein (anti-CENP-A) specific antibodies from immunoblots of HeLa nuclear protein. The antibodies react with epitopes present on CENP-A derived from humans but apparently do not recognize specific epitopes in either rat or chicken nuclei. Only human nuclear protein is CENP-A positive by immunoblot. Furthermore, human cells show localization of anti-CENP-A antibody to centromeres by immunofluorescence microscopy, whereas rat cells do not. On extraction from the nucleus, CENP-A copurifies with core histones and with nucleosome core particles. We conclude that this centromere-specific protein is a histone-like component of chromatin. The data suggest that CENP-A functions as a centromere-specific core histone.

Retroviral gene transfer into diploid fibroblasts for gene therapy

Abstract: A process of mammalian gene therapy. Explanted fibroblasts are genetically modified by introducing a retroviral construct containing a nucleotide sequence encoding for a therapeutic substance. The genetically modified fibroblasts are implanted into a mammalian subject.

Evidence for a locus activation region: the formation of developmentally stable hypersensitive sites in globin-expressing hybrids

Abstract: We have analyzed the chromatin structure of the human beta-globin locus in somatic cell hybrids resulting from the fusion of human non-erythroid cells and mouse erythroleukemia (MEL) cells. In these hybrids, the human adult beta-globin gene, but neither the embryonic nor fetal globin genes, is activated transcriptionally. In addition, the DNase I-resistant beta-like globin locus characteristic of the parental non-erythroid human cells (1,2) is reorganized over an approximately 80 kb region, including the formation of the developmentally stable hypersensitive sites 50 kb 5' and 20 kg 3' of the activated adult beta-globin gene (2,3). These results are consistent with the hypothesis that events occurring at the 5' and/or 3' developmentally stable hypersensitive sites are important, if not necessary, for the activation of the beta-globin locus.

Similarity between cell-cycle genes of budding yeast and fission yeast and the Notch gene of Drosophila.

Abstract: The HO gene of Saccharomyces cerevisiae encodes the endonu-clease1 that initiates mating-type switching2. To prevent inopportune switching, HO transcription is restricted to a specific period in the haploid3–5 cell cycle, which is just after, and dependent on, the start of the mitotic cell cycle6. A repeated promoter element (CACGA4) (refs 7–9) and two trans-acting activators (SWI4 and SWI6)9 have been identified, which are responsible for the periodic and start-dependent transcription of HO. To understand further the link between start and HO transcription, the SWI6 gene has been cloned and sequenced. The SWI6 protein is similar to the protein in Schizosaccharomyces pombe that is encoded by cdc10 an essential gene specifically required at the start of the cell cycle12,13. The similarity between the SWI6 and cdc10 products, and their common involvement with 'start', suggest that they may share a common mechanism for sensing or executing this critical control step in the cell cycle. The SWI6 and cdc10 proteins also contain two copies of a repeated motif that occurs at least five times in the cytoplasmic domain of the Notch protein of Drosophila melanogaster.

Immunohistochemical study of the expression of a Mr 34,000 human epithelium-specific surface glycoprotein in normal and malignant tissues.

Abstract: Monoclonal antibody HEA125 was used to study the tissue distribution of an epithelial cell surface glycoprotein of Mr 34,000 (Egp34) A large panel of normal and neoplastic tissues was examined for immunoreactivity with HEA125 by means of a sensitive immunoperoxidase technique HEA125 labeled most epithelial cell types throughout the body but did not label any nonepithelial tissue Major exceptions were epidermal keratinocytes, gastric parietal cells, hepatocytes, thymic cortical epithelial, and myoepithelial cells Normal mesothelial cells were unreactive In normal glandular epithelia and tubular adenocarcinomas exclusively the basolateral cell membranes were stained HEA125 intensely reacted with all tested carcinoma specimens derived from colorectum, stomach, pancreas, liver, lung, mammary gland, ovary, thyroid, kidney, urinary bladder, and prostate including a number of anaplastic, diffusely infiltrating carcinomas Metastatic lesions of these tumors were consistently positive Generally, the staining of tumor cells was very homogeneous The majority of squamous cell carcinomas were less strongly labeled than adenocarcinomas; keratinizing areas of the tumor masses were negative Germ cell tumors and mesotheliomas of epithelioid type focally expressed the antigen Egp34 was found to be absent from sarcomas, lymphomas, melanomas, and neurogenic tumors Hence, HEA125 is a useful reagent for the distinction of carcinomas from nonepithelial neoplasms, even at very low degrees of histological differentiation Furthermore, HEA125 allows the immunohistochemical detection of micrometastases originating from carcinomas The antigen is detectable in formalin-fixed paraffin sections

Host origin of marrow stromal cells following allogeneic bone marrow transplantation

Abstract: Although it is generally agreed that stromal cells are important in the regulation of haematopoietic cell development, the origin of these phenotypically diverse cells has been a subject for debate for more than 50 years. Data which support the concept of a separate origin for the haematopoietic stem cell and the marrow stroma are derived from cytogenetic or enzyme marker studies of explanted and expanded stromal cells grown under conditions that do not allow haematopoiesis in vitro. Recent evidence in man and in mouse suggesting that the stromal cells capable of transferring the haematopoietic microenvironment in vitro are transplantable seemingly questions this dichotomy, one interpretation being the existence of a common haematopoietic/stromal 'stem cell'. We used in situ hybridization to discriminate donor cells from host in blood and bone marrow samples obtained from patients with functioning sex-mismatched but HLA-identical allografts. Without exception, marrow-derived stromal cells that proliferate in long-term cultures were found to be of host genotype, whereas the macrophage component of the adherent layer in these cultures originated from the donor.

Density-dependent recognition of cell surface GM3 by a certain anti-melanoma antibody, and GM3 lactone as a possible immunogen: requirements for tumor-associated antigen and immunogen.

Abstract: A mouse monoclonal antibody M2590, previously established after immunization of mice (C57BL/6) with syngeneic melanoma B16 cells and showing preferential reactivity with various types of melanoma over other tumor and normal cells or tissues, was shown to be directed to GM3 ganglioside. Since GM3 is widely distributed in essentially all types of animal cells, there is a conflict with the concept of a tumor-associated antigen and immunogen. Studies on the reactivity of M2590 antibody with various cells having different GM3 density at their cell surface, including cells treated with sialidase, liposomes, and solid-phase lipid layer containing different GM3 concentrations, have indicated that 1) reactivity of the antibody M2590 depends greatly on the density of GM3 exposed at the cell surface, on liposomes, or on solid phase; and 2) there is a threshold density that is recognized by the antibody in all-or-none fashion. In addition, the antibody M2590 reacts not only with GM3 but also with GM3 lactone, and the binding affinity of the antibody to GM3 lactone is strikingly higher than to GM3; however, the antibody does not react with GM3 ethyl ester. GM3 lactone was detected in melanoma as 3H-labeled GM3 gangliosidol after melanoma cells were directly treated with NaB[3H]4. A comparative immunization of BALB/c mice with GM3 and GM3 lactone showed that GM3 lactone is a much stronger immunogen than GM3, although the antibody elicited reacts with both GM3 and its lactone. Thus, the real immunogen could be GM3 lactone, although it is a minor membrane component.

The treatment of acute non-lymphoblastic leukemia by allogeneic marrow transplantation.

Abstract: The results are presented of allogeneic transplantation for 363 patients with acute non-lymphoblastic leukemia treated in Seattle from May 1973 through December 1985. The probabilities of surviving disease-free for 5 years for patients transplanted in first remission, in second remission, in untreated first relapse or in chemotherapy-resistant first relapse were 46%, 28%, 30%, and 21%, respectively. The corresponding probabilities of relapse within 5 years were 25%, 37%, 36% and 56%, respectively. Prognostic factors predictive of survival after marrow transplantation for patients transplanted in first remission included age, donor sex and the number of circulating blasts at the time of diagnosis. Acute graft-versus-host disease (GVHD) had a major adverse effect on survival, but chronic GVHD decreased the risk of relapse for patients transplanted in first remission.

Risk Factors for Airflow Obstruction in Recipients of Bone Marrow Transplants

Abstract: Obstructive lung disease is a complication of bone marrow transplantation. To identify risk factors we analyzed pulmonary function tests of 281 adult patients 1 year after marrow transplantation. The forced expiratory volume at 1 second divided by the forced vital capacity (FEV1/FVC) was used to measure airflow rates. Factors associated with a lower year-1 FEV1/FVC (%) included increased age (p less than 0.0001), male gender (p = 0.02), cigarette smoking (p = 0.01), lower FEV1/FVC before transplantation (p less than 0.0001), HLA-nonidentical grafts (p = 0.001), chronic graft-versus-host disease (p = 0.0002), and immunosuppressive therapy with methotrexate (p = 0.01). There was no significant association between the year-1 FEV1/FVC and underlying disease, dose of conditioning irradiation, or development of acute graft-versus-host disease. Linear multivariate regression analysis, after controlling for the FEV1/FVC before transplantation, shows both chronic graft-versus-host disease and administration of methotrexate independently associated with decrements in the year-1 FEV1/FVC. The combined occurrence of chronic graft-versus-host disease and methotrexate also was strongly associated with decreases in the year-1 FEV1/FVC, indicating an interaction of these risk factors.

Efficient retrovirus-mediated transfer and expression of a human adenosine deaminase gene in diploid skin fibroblasts from an adenosine deaminase-deficient human.

Abstract: Skin fibroblasts might be considered suitable recipients for therapeutic genes to cure several human genetic diseases; however, these cells are resistant to gene transfer by most methods. We have studied the ability of retroviral vectors to transfer genes into normal human diploid skin fibroblasts. Retroviruses carrying genes for neomycin or hygromycin B resistance conferred drug resistance to greater than 50% of the human fibroblasts after a single exposure to virus-containing medium. This represents at least a 500-fold increase in efficiency over other methods. Transfer was achieved in the absence of helper virus by using amphotropic retrovirus-packaging cells. A retrovirus vector containing a human adenosine deaminase (ADA) cDNA was constructed and used to infect ADA-fibroblasts from a patient with ADA deficiency. The infected cells produced 12-fold more ADA enzyme than fibroblasts from normal individuals and were able to rapidly metabolize exogenous deoxyadenosine and adenosine, metabolites that accumulate in plasma in ADA-deficient patients and are responsible for the severe combined immunodeficiency in these patients. These experiments indicate the potential of retrovirus-mediated gene transfer into human fibroblasts for gene therapy.

Conserved arrangement of nested genes at the Drosophila Gart locus.

Abstract: The Drosophila melanogaster Gart gene encodes three enzymatic activities in the pathway for purine de novo synthesis. Alternative processing of the primary transcript leads to the synthesis of two overlapping polypeptides. The coding sequence for both polypeptides is interrupted by an intron that contains a functional cuticle protein gene encoded on the opposite DNA strand. Here we show that this nested organization also exists at the homologous locus of a distantly related species, Drosophila pseudoobscura. In both species, the intronic cuticle gene is expressed in wandering larvae and in prepupae. Remarkably, there are 24 different highly conserved noncoding segments within the intron containing the cuticle gene. These are found upstream of the transcriptional start, at the 3' end, and even within the single intronic gene intron. Other introns in the purine gene, including the intron at which alternative processing occurs, show no such homologies. It seems likely that at least some of the conserved noncoding regions are involved in specifying the high level developmental expression of the cuticle gene. We discuss the possibility that shared cis-acting regulatory sites might enhance transcription of both genes and help explain their nested arrangement.

On the epidemiology of oral contraceptives and disease.

Abstract: Publisher Summary This chapter reviews the epidemiology of oral contraceptives (OCs) and subsequent disease risk. The chapter discusses both adverse and beneficial effects in relation to a range of human diseases including a number of common cancers and important cardiovascular diseases. The chapter investigates important disease categories with emphasis on the consistency of results and, when possible,. on the apparent form of any increased or decreased risk as a function of such “exposure” features as hormone content of OC used, duration of use, and time since first and last use of OCs. An overall risk-benefit summary is presented, with an emphasis on mortality rates in the United States. The studies reviewed in the chapter are all observational—decisions concerning whether or not to use OCs and concerning the “pattern” of such use are made subjectively by the women. Because oral contraceptives have been used by many millions of women in all parts of the world for past several years, virtually all known diseases have developed in women who have used these steroid preparations.

Residential magnetic and electric fields.

Abstract: A magnetic flux density (MFD) and electric-field (E-field) data-acquisition system was built for characterizing extremely low-frequency fields in residences. Every 2 min during 24-h periods, MFD and E-field measurements were made in 43 homes in King, Pierce, and Snohomish counties of Washington State. The total electrical energy used in each residence during the 24-h measurement period was also recorded, and maps were drawn to scale of the distribution wiring within 43 m (140 ft) of these homes. Finally, on a separate date, field measurements were made in each home during an epidemiological interview. The results of this study can be summarized as follows: 1) 24-h-average MFD measured at two separate points in the family room were correlated, as were a 24-h-average bedroom measurement and the mean of the two family-room measurements. 2) The 24-h-average family-room MFD and E-field measurements were uncorrelated. 3) The 24-h-average total harmonic distortions of family-room MFD and E-fields were less than about 24% and 7%, respectively. 4) Residential MFD exhibited a definite 24-h (diurnal) cycle. 5) The 24-h-average and interviewer-measured MFD were correlated. 6) Residential 24-h-average MFD were correlated with the wiring code developed by Wertheimer and Leeper. 7) An improved prediction of 24-h-average residential MFD was obtained using the total number of service drops, the distance to neighboring transmission lines, and the number of primary phase conductors.

Human marrow transplantation: an immunological perspective.

Abstract: Publisher Summary The first successful marrow transplants were carried out with identical twins as donor for patients with acute leukemia. Later development of the one-way mixed leukocyte culture (MLC) test and alloantisera for HLA typing made it possible to select MHC-identical allogeneic donorhecipient pairs. At the same time, tolerable preparative regimens of total body irradiation (TBI) and chemotherapy capable of providing sufficient immunosuppression for engraftment of allogeneic marrow were developed, and post-transplant immunosuppressive regimens allowing at least partial control of graft-versus-host disease (GVHD) were identified. Collectively, the developments have made it possible for marrow transplantation to evolve from a last-resort experimental therapy reserved for patients with end-stage leukemia or aplastic anemia to become the first-line treatment of choice for an increasingly large number of conditions. The indications for marrow transplantation depend on the underlying disease and the degree of genetic disparity between the donor and recipient. The indications for marrow transplantation are more limited if an HLA-identical sibling is not available. Because of the increased risk of complications—such as, rejection or GVHD—marrow transplantation from a partially compatible donor should not be recommended for patients with chronic myelogenous leukemia (CML), in chronic phase or acute nonlymphocytic leukemia (ANL) in first remission, where there is a good prognosis for the immediate future or where the disease may be cured by conventional therapy. Apart from the core discussion on immunological perspective of human marrow transplantation, this chapter focuses on the four principal immunologic aspects of human marrow transplantation: hematopoietic engraftment, GVHD, immunologic reconstitution, and the graft-versus-leukemia effect.

The effect of age on the care of women with breast cancer in community hospitals.

Abstract: We studied the process of care received by 1,680 female breast cancer patients treated in 17 community hospitals. The probability of receiving various diagnostic, consultation, therapy, or rehabilitation services was almost always significantly associated with patient age for one or more disease stages. Most often there was a linear trend for older patients to receive fewer services (e.g., biopsies prior to definitive treatment, number of lymph nodes examined, chemotherapy, radiation therapy) but other age patterns also were found. Age was not significantly associated with clinical staging or estrogen receptors.

Cancer in First and Second Generation Americans

Abstract: Mortality or incidence rates of ten major neoplasms in migrants from several countries, their respective countries of origin, their American-born offspring, and United States whites were compared. Rates in succeeding generations of Americans increased most rapidly for colon cancer and most slowly for breast cancer, with ovarian cancer occupying an intermediate position and prostate cancer showing inconsistent patterns of displacement of rates among various ethnic groups. Rates of stomach, liver, and esophageal cancers declined rapidly in succeeding generations of migrants, although small residual excess risks compared to whites persisted in second generation Americans. These residual excesses were greatest for stomach cancer and least for cancer of the esophagus. Differences in rates of lung and bladder cancers were commensurate with differences in smoking patterns among the generations and ethnic groups considered. This was also true for pancreatic cancer in Asians, but not in Latin Americans. The etiological implications of these observations are discussed.

Murine c-fms cDNA: cloning, sequence analysis and retroviral expression.

Abstract: We have isolated and sequenced a cDNA clone coding for the murine c-fms gene. The 3677 nucleotide cDNA clone codes for a protein of 976 amino acids, which has 76% and 75% homology to the v-fms and human proteins, respectively. The predicted membrane protein, c-fms, has an amino terminal signal sequence and external, transmembrane and cytoplasmic domains. The homology between murine c-fms and v-fms or human c-fms is the strongest (90%-95%) in the cytoplasmic domain and weakest (59%-63%) in the external domain. The c-fms clone was inserted into a retroviral vector containing a neomycin resistance gene and cell lines resistant to G418 were isolated. These cell lines expressed protein which was immunoprecipitated by anti-c-fms antibodies and of the same size as murine c-fms. These cells were also found to specifically bind human CSF-1.