Active-specific immunotherapy for melanoma

Twenty-five patients with metastatic melanoma were treated with a therapeutic vaccine ("theraccine") consisting of allogeneic melanoma lysates and a novel adjuvant, DETOX (Ribi ImmunoChem Research, Inc, Hamilton, MT). Each patient received 200 antigenic units (20 x 10(6) tumor cell equivalents) subcutaneously on weeks 1, 2, 3, 4, and 6. Clinical responses included one complete remission, three partial remissions, and a long-term (17-month) stability. Two other patients had mixed responses, with partial remissions of numerous subcutaneous nodules. Sites of responsive disease included primarily the skin, but ileal, breast, and a liver metastasis also responded. Removal of residual lesions in patients with partial remissions, whose other lesions had disappeared during treatment, led to long disease-free survivals. The median duration of remission was 17 months, with four of the five responders alive for at least 24 months after treatment. An increase in precursors of cytolytic T cells (CTLs) correlated with clinical outcome, when complete, partial, and mixed responses and long-term stability were considered. The CTLs recognized melanoma-associated antigens on many cell lines, but not other types of tumor or normal lymphocytes. Skin-test reactivity to melanoma antigens and serum antibodies against the melanoma cells was unrelated to clinical response. Toxicity was minimal, restricted largely to minor soreness at the site of injection. Only five patients, four of whom were treated with repeated courses, developed severe granulomas. These results confirm that active-specific immunization with allogeneic lysates of melanoma administered with the adjuvant DETOX can induce immunity to melanoma, and can induce regressions of disease in a proportion of patients with metastatic disease with little toxicity.     

A comparative proteome analysis of hippocampal tissue from schizophrenic and Alzheimer's disease individuals

The proteins expressed by a genome have been termed the proteome. Comparative proteome analysis of brain tissue offers a novel means to identify biologically significant gene products that underlie psychopathology. In this study we collected post mortem hippocampal tissue from the brains of seven schizophrenic, seven Alzheimer's disease (AD) and seven control individuals. Hippocampal proteomes were visualised by two-dimensional gel electrophoresis of homogenised tissue. A mean of 549 (s.d. 35) proteins were successfully matched between each disease group and the control group. In comparison with the control hippocampal proteome, eight proteins in the schizophrenic hippocampal proteome were found to be decreased and eight increased in concentration, whereas, in the AD hippocampal proteome, 35 proteins were decreased and 73 were increased in concentration (P<0.05). One protein, which was decreased in concentration in both diseases, was characterised as diazepam binding inhibitor (DBI) by N-terminal sequence analysis. DBI can regulate the action of the GABA(A) receptor. Protein changes involved 6% of the assessed AD hippocampal proteome, whereas, in schizophrenia protein changes involved less than 1% of the assessed hippocampal proteome. We conclude that schizophrenia has a subtle neuropathological presentation and comparative proteome analysis is a viable means by which to investigate diseases of the brain at the molecular level.     

The effect of ultra-high molecular weight polyethylene wear debris on MG63 osteosarcoma cells in vitro

BACKGROUND: Focal osteolysis due to ultra-high molecular weight polyethylene wear debris involves effects on both bone resorption and bone formation. METHODS: The response of MG63 osteoblast-like osteosarcoma cells to ultra-high molecular weight polyethylene wear debris isolated by enzymatic digestion of granulomatous tissue obtained from the sites of failed total hip arthroplasties was examined. Scanning electron microscopy, particle-size analysis, and Fourier transform infrared spectroscopy were used to characterize the number, morphology, size distribution, and chemical composition of the particles. Cell response was assessed by adding particles at varying dilutions to confluent cultures and measuring changes in cell proliferation (number of cells and [3H]-thymidine incorporation), osteoblast function (alkaline-phosphatase-specific activity and osteocalcin production), matrix production (collagen production and proteoglycan sulfation), and local cytokine production (prostaglandin-E2 production). RESULTS: The mean size of the particles was 0.60 micrometer, and 95 percent of the particles had a size of less than 1.5 micrometers. The number of particles per gram of tissue ranged from 1.39 to 3.38x10(9). Three of the four batches of particles were endotoxin-free. Exposure of the cells to particles of wear debris significantly increased the number of cells (p<0.05) and the [3H]-thymidine incorporation (p<0.05) in a dose-dependent manner. In contrast, the addition of particles decreased alkaline-phosphatase-specific activity and osteocalcin production. Collagen production and proteoglycan sulfation were also decreased, while prostaglandin-E2 synthesis was increased by the addition of particles. CONCLUSIONS: Ultra-high molecular weight polyethylene particles isolated from human tissue stimulated osteoblast proliferation and prostaglandin-E2 production and inhibited cell differentiation and matrix production. These results indicate that particles of wear debris inhibit cell functions associated with bone formation and that osteoblasts may produce factors in response to wear debris that influence neighboring cells, such as osteoclasts and macrophages. CLINICAL RELEVANCE: Particles of wear debris, especially ultra-high molecular weight polyethylene, have been implicated in the loosening of implants and the development of osteolysis. The present study shows that particles of ultra-high molecular weight polyethylene isolated from human tissue inhibit osteoblast functions associated with bone formation. In addition, particles of wear debris induced osteoblasts to secrete factors capable of influencing neighboring cells, such as osteoclasts and macrophages. These results suggest that osteoblasts may play a role in the cascade of events leading to granuloma formation, osteolysis, and failure of orthopaedic implants.     

Identification of bacterial pathogens in patients with endophthalmitis by 16S ribosomal DNA typing

PURPOSE: To determine whether sequence analysis of 16S ribosomal DNA (rDNA) can be used to detect bacterial pathogens in patients with postoperative endophthalmitis. METHODS: In 10 eyes of 10 patients, vitreous specimens were collected for culture and rDNA typing. Variable segments of each ribosomal DNA specimen were amplified by polymerase chain reaction (PCR), sequenced, and aligned by BLAST, a computer alignment program, against sequences in GenBank at the National Institutes of Health. RESULTS: Specimens were available from five eyes with bacterial endophthalmitis diagnosed by Gram stain or culture. Amplified 16s rDNA sequences from the eyes of three patients were identical to microbiologic results. Polymerase chain reaction results were negative in two cases in which unusual organisms were detected. All five control specimens from patients with nonbacterial endophthalmitis or uveitis were PCR negative. Approximately 48 to 72 hours are required under ideal conditions for final species identification with this ribosomal typing technique. CONCLUSIONS: 16S rDNA typing shows potential as a relatively rapid technique for identifying bacteria in vitreous samples.     

Prostate cancer old problems and new approaches

Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored.     

Growth and growth hormone in children during and after therapy for acute lymphoblastic leukaemia

Growth impairment and growth hormone (GH) deficiency have been reported in children treated for acute lymphoblastic leukaemia (ALL). We have studied growth and GH secretion in a group of 50 patients, affected by ALL, during a 2- to 5-year period after diagnosis, and in 12 long-term-survivors. We observed a significant decrease in growth velocity during the 1st year (in particular during the first 6 months) of therapy and a catch-up growth after the end of therapy. Longterm survivors did not exhibit a significant reduction of height standard deviation score (SDS), as compared to height SDS at diagnosis. None of the patients showed GH deficiency. Our data indicate that chemotherapy significantly affects growth of patients treated for ALL, whereas radiotherapy-at the doses used in this study-does not induce GH deficiency, at least not within 9 years after diagnosis.     

Quercetin inhibits the growth of a multidrug-resistant estrogen-receptor-negative MCF-7 human breast-cancer cell line expressing type II estrogen-binding sites

Summary It has been demonstrated that the flavonoid quercetin (3,3,4,5,7-pentahydroxyflavone; Q) inhibits the growth of several cancer cell lines. There is evidence suggesting that the antiproliferative activity of this substance is mediated by the so-called type II estrogen-binding, site (type II EBS). We looked for the presence of type II EBS and the effect of Q on the proliferation of an Adriamycinresistant estrogen-receptor-negative human breast-cancer cell line (MCF-7 ADRr). By whole-cell assay using estradiol labelled with 6,7-tritium ([³H]-E2) as a tracer, we demonstrated that MCF-7 ADRr cells contain type II EBSs. Competition analysis revealed that diethylstilbestrol (DES) and Q competed with similar potency for [³H]-Es binding to type II EBSs. The antiestrogen tamoxifen (TAM) competed for type II EBSs, albeit to a lesser extent than either DES or Q. Growth experiments demonstrated that Q and DES exerted a dose-dependent inhibition of cell proliferation in the range of concentrations between 10 nM and 10 m, whereas TAM was less effective. Q could also inhibit colony formation in a clonogenic assay. Our results indicate that multidrug-resistant estrogen-receptor-negative MCF-7 cells express, type II EBSs and are sensitive to the inhibitory effect of Q. This substance could be the parent compound of a novel class of anticancer agents.