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1.
J Clin Nurs ; 30(13-14): 1942-1952, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33829575

ABSTRACT

AIMS AND OBJECTIVES: To investigate patients' experiences of being involved in their care in the emergency department (ED). BACKGROUND: Previous research shows that when patients experience involvement during care visits, this increased their trust in the care, gave a sense of control and promoted their autonomy. DESIGN: A qualitative descriptive design with semi-structured interviews, using the "Consolidated criteria for reporting qualitative research" (COREQ) checklist. METHODS: Using convenience sampling, semi-structured interviews were conducted with 16 patients in the ED. RESULTS: The study identified four categories: attention and inattention; communication and understanding; varying levels of participation; and inefficient and inaccessible care. The results show that patients expected to be treated with respect and to be involved in an open dialogue about their care. Patients' experiences of participation were related to their sense of control. CONCLUSIONS: Based on the results of the study, the authors found that factors such as dialogue, information, attention and participation affected the patients' involvement during the ED visit. Experiences of involvement and control were linked to patients' experiences of care and of patients as individuals. RELEVANCE TO CLINICAL PRACTICE: Healthcare providers' awareness of the importance of paying attention to the patient as an individual, and of the need for simple, continuous communication could facilitate patient involvement in own care.


Subject(s)
Emergency Service, Hospital , Motivation , Health Personnel , Humans , Patient Participation , Qualitative Research
2.
J Nutr Health Aging ; 20(3): 275-9, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26892576

ABSTRACT

OBJECTIVES: To investigate the correlation between MMSE ≤ 23 and the presence of a diagnosis of dementia in the medical record in a population with multimorbidity. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study was part of the Ambulatory Geriatric Assessment - a Frailty Intervention Trial (AGe-FIT; N = 382). Participants were community dwelling, aged ≥ 75 years, had received inpatient hospital care at least three times during the past 12 months, and had three or more concomitant diagnoses according to the International Classification of Diseases, 10th revision. MEASUREMENTS: The Mini Mental State Examination (MMSE) was administered at baseline. Medical records of participants with MMSE scores < 24 were examined for the presence of dementia diagnoses and two years ahead. RESULTS: Fifty-three (16%) of 337 participants with a measure of MMSE had a MMSE scores < 24. Six of these 53 (11%) participants had diagnoses of dementia (vascular dementia, n = 4; unspecified dementia, n = 1; Alzheimers disease, n = 1) according to medical records; 89% did not. CONCLUSIONS: A MMSE-score < 24 is not well correlated to a diagnosis of dementia in the medical record in a population of elderly with multimorbidity. This could imply that cognitive decline and the diagnosis of dementia remain undetected in older people with multimorbidity. Proactive care of older people with multimorbidity should focus on cognitive decline to detect cognitive impairment and to provide necessary help and support to this very vulnerable group.


Subject(s)
Cognitive Dysfunction/diagnosis , Cognitive Dysfunction/epidemiology , Comorbidity , Dementia/diagnosis , Dementia/epidemiology , Geriatric Assessment , Aged , Aged, 80 and over , Aging/psychology , Alzheimer Disease/diagnosis , Alzheimer Disease/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Neuropsychological Tests
3.
Appl Nurs Res ; 28(4): 322-7, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26608433

ABSTRACT

CONTEXT: Older people with multimorbidity are vulnerable and often suffer from conditions that produce a multiplicity of symptoms and a reduced health-related quality of life. OBJECTIVES: The aim of this study is to explore the experience of living with a high symptom burden from the perspective of older community-dwelling people with multi-morbidity. METHOD: A qualitative descriptive design with semi-structured interviews, including 20 community-dwelling older people with multi-morbidity and a high symptom burden. The participants were 79-89 years old with a mean of 12 symptoms per person. Data were analyzed using content analyses. RESULTS: The experience of living with a high symptom burden revealed the overall theme, "To adjust and endure" and three sub-themes. The first sub-theme was "To feel inadequate and limited". Participants reported that they no longer had the capacity or the ability to manage, and they felt limited and isolated from friends or family. The second sub-theme was "To feel dependent". This was a new and inconvenient experience; the burden they put on others caused a feeling of guilt. The final sub-theme was "To feel dejected". The strength to manage and control their conditions was gone; the only thing left to do was to sit or lie down and wait for it all to pass. CONCLUSION: This study highlights the importance of a holistic approach when taking care of older people with multi-morbidity. This approach should employ a broad symptom assessment to reveal diseases and conditions that are possible to treat or improve.


Subject(s)
Comorbidity , Cost of Illness , Quality of Life , Aged , Aged, 80 and over , Female , Humans , Independent Living , Male , Qualitative Research
4.
BMJ Open ; 2(6)2012.
Article in English | MEDLINE | ID: mdl-23166138

ABSTRACT

OBJECTIVE: To explore the interactions concerning the frail and elderly patients having to do with discharge from acute hospital wards and their participation in medical decision-making. The views of the patients and the medical staff were both investigated. DESIGN: A qualitative observational and interview study using the grounded theory. SETTING AND PARTICIPANTS: The setting was three hospitals in rural and urban areas of two counties in Sweden of which one was a teaching hospital. The data comprised observations, healthcare staff interviews and patient interviews. The selected patients were all about to be informed that they were going to be discharged. RESULTS: The patients were seldom invited to participate in the decision-making regarding discharge. Generally, most communications regarding discharge were between the doctor and the nurse, after which the patient was simply informed about the decision. It was observed that the discharge information was often given in an indirect way as if other, albeit absent, people were responsible for the decision. Interviews with the healthcare staff revealed their preoccupation with the need to free up beds: 'thinking about discharge planning all the time' was the core category. This focus not only failed to fulfil the complex needs of elderly patients, it also generated feelings of frustration and guilt in the staff, and made the patients feel unwelcome. CONCLUSIONS: Frail elderly patients often did not participate in the medical decision-making regarding their discharge from hospital. The staff was highly focused on patients getting rapidly discharged, which made it difficult to fulfil the complex needs of these patients.

5.
Gynecol Oncol ; 95(1): 9-15, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15385104

ABSTRACT

OBJECTIVES: The serum tumor marker CA 125 is elevated in most clinically advanced ovarian carcinomas. Because these elevations may precede clinical detection by a year or more, CA 125 is potentially useful for early detection as part of an ovarian cancer screening program. However, CA 125 is often not elevated in clinically detected cancer and is frequently elevated in women with benign ovarian tumors. CA 125 may be more useful in conjunction with one or more other tumor biomarkers. Additional markers could play a role if, when used with CA 125, they identify some carcinomas missed by CA 125 (i.e., they improve sensitivity), rule out false positives (i.e., improve specificity), or are able to detect the same cancers earlier. METHODS: We have evaluated a composite marker (CM) that combines CA 125 and a previously described soluble mesothelin related (SMR) marker in sera from 52 ovarian cancer cases, 43 controls with benign ovarian tumors, and 220 normal risk controls who participated in a screening program, including 25 healthy women having two serum samples collected 1 year apart. CA 125, SMR, and CM were evaluated for their ability to identify clinical disease and for their temporal stability, which assesses their ability to obtain even greater sensitivity when used in a longitudinal screening program. RESULTS: CM has the best sensitivity, with specificity equal to CA 125. Importantly, CM has temporal stability at least as high as CA 125. CONCLUSION: The CM may outperform CA 125 alone in a longitudinal screening program as well as in a diagnostic setting.


Subject(s)
CA-125 Antigen/blood , Membrane Glycoproteins/blood , Ovarian Neoplasms/blood , Case-Control Studies , Enzyme-Linked Immunosorbent Assay , Female , GPI-Linked Proteins , Humans , Longitudinal Studies , Mesothelin , Ovarian Diseases/blood , ROC Curve , Sensitivity and Specificity
6.
Acta Anaesthesiol Scand ; 45(6): 710-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11421829

ABSTRACT

BACKGROUND: To identify risk factors for nosocomial infection in intensive care and to provide a basis for allocation of resources. METHODS: Long-term prospective incidence study of risk factors for nosocomial infection in the surgical-medical intensive care unit of a university hospital. RESULTS: A total of 2671 patients were admitted during four years, and 562 of 574 patients staying >48 h were observed during 4921 patient days (median length of stay 5 days, range 2-114). Of these, 196 (34%) patients had 364 nosocomial infections after median 8-10 days, an infection rate of 14/100 admissions. Infection prolonged length of stay 8-9 days and doubled the risk of death. The infections were 17% blood stream, 26% pneumonias, 34% wound, 10% urinary tract and 13% other infections. The incidence of bloodstream infection declined significantly during the study years, from 12% to 5%. In multiple regression analysis, the important variables for infection were central venous catheter, mechanical ventilation, pleural drainage and trauma with open fractures. High age, immunosuppression and infection on admission did not influence the risk of acquiring infection. Trauma patients constituted 24% of the study population. Trauma with open fractures increased the risk of infection more than twice (P=0.003), mainly due to wound infections. CONCLUSION: Trauma cases, with open fractures, were the patients most at risk of infection, despite low disease severity scores. Resources to prevent nosocomial infection should be allocated to these patients.


Subject(s)
Critical Care , Cross Infection/epidemiology , Adolescent , Adult , Aged , Analysis of Variance , Cross Infection/blood , Cross Infection/mortality , Female , Humans , Immunosuppression Therapy , Intensive Care Units , Male , Middle Aged , Pneumonia/epidemiology , Prospective Studies , Risk Factors , Shock/complications , Surgical Wound Infection/epidemiology , Treatment Outcome , Urinary Tract Infections/epidemiology , Wounds and Injuries/complications
7.
Proc Natl Acad Sci U S A ; 98(12): 6783-8, 2001 Jun 05.
Article in English | MEDLINE | ID: mdl-11371607

ABSTRACT

Lymphocytes from blood or tumors of patients with advanced cancer did not proliferate and produced very low levels of tumor necrosis factor and IFN-gamma when cultured with autologous tumor cells. Proliferation and lymphokine production dramatically increased in the presence of beads conjugated with mAbs to CD3 plus mAbs to CD28 and/or CD40, and the lymphocytes destroyed the tumor cells. Expression density of CD3 concomitantly increased from low to normal levels. Furthermore, beads providing a CD3 signal (in combination with CD28 or CD28 plus CD40) gave partial protection against the inhibitory effect of transforming growth factor type beta1 on lymphocyte proliferation and production of tumor necrosis factor and IFN-gamma. MHC class I-restricted cytolytic T cells lysing autologous tumor cells in a 4-h Cr(51) release assay were generated when peripheral blood leukocytes were activated in the presence of autologous tumor cells and anti-CD3/CD28 or anti-CD3/CD28/CD40 beads. Experiments performed in a model system using anti-V-beta1 or anti-V-beta2 mAbs to activate subsets of T cells expressing restricted T cell receptor showed that lymphocytes previously activated by anti-V-beta can respond to CD3 stimulation with vigorous proliferation and lymphokine production while retaining their specificity, also in the presence of transforming growth factor type beta1. Our results suggest that T lymphocytes from cancer patients can proliferate and form Th1 type lymphokines in the presence of autologous tumor cell when properly activated, and that antigen released from killed tumor cells and presented by antigen-presenting cells in the cultures facilitates the selective expansion of tumor-directed, CD8(+) cytolytic T cells.


Subject(s)
CD3 Complex/physiology , Lymphocyte Activation , Lymphocytes, Tumor-Infiltrating/immunology , Neoplasms/immunology , Antibodies, Monoclonal/immunology , CD28 Antigens/physiology , CD40 Antigens/physiology , Coculture Techniques , Histocompatibility Antigens Class I/physiology , Humans , Interferon-gamma/biosynthesis , Neoplasms/therapy , Transforming Growth Factor beta/physiology , Tumor Necrosis Factor-alpha/biosynthesis
8.
Cancer Res ; 61(6): 2420-3, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11289108

ABSTRACT

The transmembrane receptor encoded by the HER-2 cellular oncogene is amplified in several types of human carcinomas and provides an attractive therapeutic target. Shown by immunohistology, <25% of newly diagnosed ovarian carcinomas express the HER-2 protein. However, now we report that this protein was expressed in all 20 tumor cell lines derived from stage III and IV ovarian cancers as well as in tumor cells harvested from patients with malignant ascites and in tumor samples taken at a second surgery, suggesting that cells with excess expression may have a selective growth advantage. HER-2-positive ovarian carcinoma cells were shown to be sensitive to antibody-dependent cellular cytotoxicity, and their in vitro proliferation was inhibited by anti-HER-2 MAb Herceptin. We postulate, therefore, that therapy which targets HER-2 may be more efficacious in patients with ovarian carcinoma than indicated by the commonly low expression of HER-2 in tumors removed at the time of primary surgery.


Subject(s)
Carcinoma/metabolism , Ovarian Neoplasms/metabolism , Receptor, ErbB-2/biosynthesis , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal, Humanized , Antibody-Dependent Cell Cytotoxicity/drug effects , Antibody-Dependent Cell Cytotoxicity/immunology , Antineoplastic Agents/immunology , Antineoplastic Agents/pharmacology , Carcinoma/genetics , Carcinoma/immunology , Carcinoma/pathology , Cell Division/drug effects , Female , Growth Inhibitors/immunology , Growth Inhibitors/pharmacology , Humans , Ovarian Neoplasms/genetics , Ovarian Neoplasms/immunology , Ovarian Neoplasms/pathology , Receptor, ErbB-2/genetics , Receptor, ErbB-2/immunology , Trastuzumab , Tumor Cells, Cultured
9.
J Immunol ; 166(6): 3865-72, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11238630

ABSTRACT

To help determine CD83 function, a cDNA encoding a soluble protein containing the CD83 extracellular domain was fused with a mutated human IgG1 constant region (CD83Ig) and expressed by stable transfection of Chinese hamster ovary cells. Purified CD83Ig bound to peripheral blood monocytes and a subset of activated CD3(+)CD8(+) lymphocytes but did not bind to FcR. Monocytes that had adhered to plastic lost their ability to bind to CD83Ig after 90 min of in vitro incubation. CD83Ig bound to two of five T cell lines tested, HPB-ALL and Jurkat. The binding to HPB-ALL cells significantly increased when they were grown at a low pH (pH 6.5), whereas binding to Jurkat cells increased after apoptosis was induced with anti-Fas mAb. B cell and monocytic lines did not bind CD83Ig and neither did CD56(+) NK cells or granulocytes. Full-length CD83 expressed by a transfected carcinoma line mediated CD83-dependent adhesion to HPB-ALL cells. CD83Ig immunoprecipitated and immunoblotted a 72-kDa protein from HPB-ALL cells. Binding of CD83Ig to HPB-ALL cells was eliminated by neuraminidase treatment of the cells. We conclude that CD83 is an adhesion receptor with a counterreceptor expressed on monocytes and a subset of activated or stressed T lymphocytes, and that interaction between CD83 and its counterreceptor is dependent upon the state of glycosylation of a 72-kDa counterreceptor by sialic acid residues. In view of the selectivity of the expression of CD83 and its ligand, we postulate that the interaction between the two plays an important role in the induction and regulation of immune responses.


Subject(s)
CD8-Positive T-Lymphocytes/metabolism , Cell Adhesion Molecules/metabolism , Immunoglobulins/metabolism , Lymphocyte Activation , Membrane Glycoproteins/metabolism , Monocytes/metabolism , N-Acetylneuraminic Acid/metabolism , Receptors, Mitogen/metabolism , T-Lymphocyte Subsets/metabolism , Animals , Antigens, CD , Binding, Competitive/genetics , Biotinylation , CD8-Positive T-Lymphocytes/immunology , CHO Cells , COS Cells , Cell Adhesion/immunology , Cell Adhesion Molecules/antagonists & inhibitors , Cell Adhesion Molecules/genetics , Cell Line , Cell-Free System/immunology , Cricetinae , HL-60 Cells , Humans , Immunoblotting , Immunoglobulins/genetics , Immunosuppressive Agents/metabolism , Immunosuppressive Agents/pharmacology , Jurkat Cells , Ligands , Lymphocyte Activation/genetics , Membrane Glycoproteins/antagonists & inhibitors , Membrane Glycoproteins/genetics , Molecular Weight , Monocytes/immunology , Mutagenesis, Site-Directed , N-Acetylneuraminic Acid/isolation & purification , Precipitin Tests , Protein Binding/genetics , Protein Binding/immunology , Receptors, Mitogen/antagonists & inhibitors , Receptors, Mitogen/genetics , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/chemical synthesis , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/metabolism , T-Lymphocyte Subsets/immunology , Transfection , U937 Cells , CD83 Antigen
11.
Br J Nurs ; 10(11): 710-4, 2001.
Article in English | MEDLINE | ID: mdl-12048486

ABSTRACT

Person-centred care for people with dementia is an aspiration of both family and professional carers, but what constitutes person-centred care and how it can be achieved is less clear. This article describes a Swedish study in which in-depth interviews were completed with both family and professional carers of people with dementia with the purpose of exploring what they considered to be "best care". Important areas of similarity and difference were identified and the results suggest that both groups of carers need to work closely together if person-centred care is to become a reality.


Subject(s)
Attitude of Health Personnel , Attitude to Health , Caregivers/psychology , Day Care, Medical/standards , Dementia/therapy , Family/psychology , Quality of Health Care , Respite Care/standards , Benchmarking , Clinical Competence/standards , Day Care, Medical/psychology , Female , Humans , Knowledge , Male , Needs Assessment , Nursing Methodology Research , Patient-Centered Care/standards , Respite Care/psychology , Social Support , Surveys and Questionnaires , Sweden
12.
Neurosurgery ; 46(3): 704-9, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10719867

ABSTRACT

OBJECTIVE: To evaluate dose intensification with osmotic blood-brain barrier disruption (BBBD) and the potential use of drug targeting with monoclonal antibody (MAb) BR96 conjugated to doxorubicin (BR96-DOX, now called SGN15) for treatment of intracerebral and subcutaneous human LX-1 small cell lung carcinoma xenografts in rats. METHODS: LX-1 tumors with high, low, or heterogeneous levels of the Lewis(y) antigen for BR96 were evaluated. Rats were treated with intracarotid or intravenous BR96-DOX, with or without osmotic BBBD. RESULTS: Both BR96-DOX and MAb BR96 treatment resulted in significant regression of subcutaneous tumors, in contrast to control groups including doxorubicin alone, saline, or nonbinding doxorubicin immunoconjugate. BR96-DOX delivered with BBBD to brain tumors with low antigen expression resulted in significantly (P < 0.001) increased rat survival time compared with animals that received intravenous or intra-arterial BR96-DOX. CONCLUSION: The combination of an effective drug such as doxorubicin with a MAb to facilitate tumor-selective localization and osmotic BBBD to increase tumor delivery may have practical application in the clinic, because an increased delivery of drug to tumor can be obtained without increasing the dose of systemic drug.


Subject(s)
Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , Doxorubicin/administration & dosage , Immunotoxins/administration & dosage , Animals , Antibodies, Monoclonal/pharmacology , Antigens, Neoplasm/analysis , Antigens, Neoplasm/immunology , Antineoplastic Agents/pharmacology , Blood-Brain Barrier , Brain Neoplasms/immunology , Carotid Arteries , Doxorubicin/pharmacology , Female , Humans , Immunotoxins/pharmacology , Injections, Intra-Arterial , Injections, Intravenous , Neoplasm Transplantation , Rats , Rats, Nude , Survival Analysis , Transplantation, Heterologous
13.
Clin Cancer Res ; 5(11): 3632-8, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10589780

ABSTRACT

The efficacy of chemotherapy has been improved by regimens that combine several cytotoxic drugs with different mechanisms of action and/or different dose-limiting toxicities. Here we demonstrate clearly, and for the first time, that combined therapy using an anticarcinoma immunoconjugate, BR96-doxorubicin, and the cytotoxic drug paclitaxel results in a significant increase in antitumor activity over that of either agent alone. Synergistic activity was seen at doses of BR96-doxorubicin that were minimally active as single agents. A dramatic increase in regression rates was seen when a regimen that combined BR96-doxorubicin and paclitaxel was used to treat both paclitaxel-sensitive and paclitaxel-insensitive carcinomas. Importantly, combined therapy resulted in increased antitumor activity against lung, colon, and breast tumors xenografted in athymic mice and large, paclitaxel-insensitive colon tumors xenografted in athymic rats that also express the Lewis(y) target antigen in normal tissues.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Doxorubicin/therapeutic use , Neoplasms/drug therapy , Paclitaxel/therapeutic use , Adenocarcinoma/drug therapy , Adenocarcinoma/pathology , Animals , Antibodies, Monoclonal/administration & dosage , Antineoplastic Agents/administration & dosage , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Colonic Neoplasms/drug therapy , Colonic Neoplasms/pathology , Doxorubicin/administration & dosage , Drug Resistance, Neoplasm , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/pathology , Mice , Mice, Nude , Neoplasms/pathology , Paclitaxel/administration & dosage , Rats , Rats, Nude , Time Factors , Transplantation, Heterologous , Tumor Cells, Cultured
14.
Proc Natl Acad Sci U S A ; 96(20): 11531-6, 1999 Sep 28.
Article in English | MEDLINE | ID: mdl-10500211

ABSTRACT

mAb OV569 was made by immunizing mice with ovarian carcinoma cells. It binds to cells from ovarian carcinomas and, to a lesser extent, to cells from certain other carcinomas whereas the binding to normal tissues is low to nondetectable. It also binds to soluble molecule(s) in culture supernatants from antigen-positive carcinomas. OV569 recognizes a protein(s) of 42-45 kDa with the same N-terminal amino acid sequence as the membrane-bound portion of mesothelin and megakaryocyte potentiating factor (MPF). Binding assays with fusion proteins comprising either the N-terminal part of mesothelin/MPF (D1Ig), reported to be easily cleaved off, or a noncleavable, membrane-associated part (D2Ig) showed that OV569 only binds to D2hIg. A new member of the mesothelin/MPF family was discovered, which has an 82-bp insert in the membrane-associated part, leading to a frameshift of 212 bp, and whose predicted molecular structure indicates that it is soluble. To test patient sera for soluble tumor antigen, antigen was isolated from cell-free tumor culture supernatants via immunoadsorption with OV569 and used to generate murine mAbs to an epitope different from the one to which OV569 binds, after which mAbs to two different epitopes were used to develop a "sandwich ELISA." Using this assay, the level of circulating antigen was elevated significantly in 23 of 30 sera from patients with ovarian carcinoma, as compared with 0 of 68 sera from healthy controls, 0 of 3 sera from patients with nonneoplastic diseases, and 25 of 75 sera from patients with other tumors. Soluble molecules of the mesothelin/MPF family may provide useful new marker(s) for diagnosis of ovarian carcinoma and/or monitoring its response to therapy.


Subject(s)
Antigens, Neoplasm/blood , Biomarkers, Tumor/blood , Membrane Glycoproteins/blood , Ovarian Neoplasms/blood , Proteins/analysis , Amino Acid Sequence , Animals , Cloning, Molecular , Enzyme-Linked Immunosorbent Assay , Female , GPI-Linked Proteins , Humans , Membrane Glycoproteins/chemistry , Membrane Glycoproteins/genetics , Mesothelin , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Proteins/chemistry , Proteins/genetics
16.
Biochem Soc Symp ; 63: 199-210, 1998.
Article in English | MEDLINE | ID: mdl-9513724

ABSTRACT

Members of the epidermal growth factor (EGF) family of tyrosine kinase receptors are involved in the regulation of cell growth and differentiation, and are found to be expressed in many types of cancers. Activation of these receptors can be elicited by multiple ligands, resulting in the formation of a spectrum of heterodimer complexes and a number of biological outcomes. A clear demonstration of biological activation by a single complex has been difficult to address because of the endogenous expression of HERs (human EGF-like receptors) in many cell lines. We have generated a collection of cell lines expressing all HERs alone or in all pairwise combinations in a clone of NIH 3T3 cells (3T3-7d) devoid of detectable EGF receptor family members. Transformation, as measured by growth in soft agar, only occurred in cells expressing two different HER family members. Transformation with activated Neu and the rate of in vivo tumour formation were also correlated with the expression of multiple HERs in the same cell. To further our understanding of the role of heterodimer signalling, we demonstrated that, within a breast carcinoma cell line, activation of HER-3 results in cellular differentiation, prolonged activation of extracellular-signal-related kinase 1 (ERK1) activity and an increase in p21CIP1/WAF1 nuclear staining. In contrast, activation of HER-4 is mitogenic, induces transient activation of ERK1 activity and decreases the nuclear staining of p21CIP1/WAF1. These differences in biochemical and biological responses are correlated with the contrasting abilities of HER-3 and HER-4 to be down-regulated from the cell surface. The cell-surface localization of HER-3 does not change in response to ligand, whereas activation of HER-4 results in a loss of cell-surface staining followed by accumulation into a perinuclear compartment.


Subject(s)
Breast Neoplasms/pathology , Cell Differentiation , Cell Division , ErbB Receptors/physiology , 3T3 Cells , Animals , ErbB Receptors/genetics , Humans , Mice , Proto-Oncogene Proteins/genetics , Receptor, ErbB-2/genetics , Receptor, ErbB-3 , Receptor, ErbB-4 , Transfection , Tumor Cells, Cultured
18.
Cancer Res ; 57(20): 4530-6, 1997 Oct 15.
Article in English | MEDLINE | ID: mdl-9377565

ABSTRACT

The internalizing monoclonal antibody BR96 was conjugated to the anticancer drug doxorubicin (DOX) using an acid-labile hydrazone bond to DOX and a thioether bond to the monoclonal antibody. The resulting conjugate, termed BR96-DOX, binds to a tumor-associated Lewis(y) antigen that is abundantly expressed on the surface of human carcinoma cells. BR96-DOX binds to RCA, a human colon carcinoma cell line, and BN7005, a transplantable colon carcinoma induced in a Brown Norway (BN) rat by 1,2-dimethyl-hydrazine. BR96-DOX produces cures of established s.c. RCA human colon carcinomas in athymic mice and rats. BR96-DOX also cured both s.c. and intrahepatic BN7005 tumors in immunocompetent BN rats. Unconjugated DOX, given at its maximum tolerated dose, and matching doses of nonbinding IgG-DOX conjugate were not active against RCA or BN7005 carcinomas. An anticonjugate antibody response was produced in BN rats treated with BR96-DOX. However, this could be largely prevented by administering the immunosuppressive drug deoxyspergualin. These results confirm the concept of antibody-directed therapy in models in which the targeted antigen is expressed both in normal tissues and tumors. The findings in BN7005 further demonstrate efficacy of BR96-DOX therapy in a model in which the tumor is syngeneic and the host is immunocompetent.


Subject(s)
Adenocarcinoma/drug therapy , Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Colonic Neoplasms/drug therapy , Doxorubicin/therapeutic use , Adenocarcinoma/pathology , Adenocarcinoma/secondary , Animals , Colonic Neoplasms/pathology , Female , Humans , Immunotoxins/therapeutic use , Liver Neoplasms/drug therapy , Liver Neoplasms/pathology , Liver Neoplasms/secondary , Mice , Mice, Nude , Rats , Rats, Inbred BN , Transplantation, Heterologous , Transplantation, Isogeneic , Tumor Cells, Cultured
19.
Proc Natl Acad Sci U S A ; 94(15): 8110-5, 1997 Jul 22.
Article in English | MEDLINE | ID: mdl-9223323

ABSTRACT

Previously, we have reported on successful imaging of colon, rectal, and pancreatic carcinomas in patients by using a radiolabeled all-human monoclonal antibody, COU-1, directed against modified cytokeratin. To further develop this antibody for use as an immunoconjugate, COU-1 was cloned by phage display selection and the human Fab fragment was expressed in bacteria. Analysis by confocal laser scanning microscopy demonstrated that COU-1 bound in a uniform punctate pattern to the surface of viable carcinoma cells stained at 4 degrees C, and binding increased significantly when cells were cultured on fibronectin, laminin, or collagen IV. In the case of fibronectin, COU-1 staining was particularly enhanced at intercellular junctions. When carcinoma cells were cultured with COU-1 at 37 degrees C for 6 hr, the antibody was found in large perinuclear vesicles and the punctate surface staining was significantly reduced. Similar results were obtained using intact IgM COU-1 and the recombinant Fab fragment. Immunohistological studies indicated that COU-1, in contrast to murine monoclonal antibodies against normal cytokeratin 8 and 18, could differentiate between malignant and normal colon epithelia, and between colon cancer metastasis in the liver and surrounding normal hepatocytes. Within biopsies of malignant tissue, COU-1 exhibited membrane-associated staining of proliferating cells, while resting cells had a filamentous pattern. Thus, modified cytokeratin at the surface of carcinoma cells may represent a new target for immunoconjugates and may explain the promising results of the phase I/II clinical study.


Subject(s)
Antibodies, Monoclonal/immunology , Colonic Neoplasms/metabolism , Endocytosis , Immunoglobulin Fab Fragments/immunology , Keratins/metabolism , Amino Acid Sequence , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal, Humanized , Bacteriophages/genetics , Binding Sites, Antibody , Cell Line , Colon/immunology , Colon/metabolism , Colonic Neoplasms/immunology , Humans , Immunoglobulin Fab Fragments/chemistry , Intestinal Mucosa/immunology , Intestinal Mucosa/metabolism , Keratins/immunology , Molecular Sequence Data , Recombinant Proteins/immunology
20.
Bioconjug Chem ; 8(4): 510-9, 1997.
Article in English | MEDLINE | ID: mdl-9258449

ABSTRACT

The L49 (IgG1) monoclonal antibody binds to p97 (melanotransferrin), a tumor-selective antigen that is expressed on human melanomas and carcinomas. A recombinant fusion protein, L49-sFv-bL, that contains the antibody binding regions of L49 fused to the Enterobacter cloacae r2-1 beta-lactamase (bL) was constructed, expressed, and purified to homogeneity in an Escherichia coli soluble expression system. The variable regions of L49 were cloned by reverse transcription-polymerase chain reaction from L49 hybridoma mRNA using signal sequence and constant region primers. Construction of the gene encoding L49-sFv-bL was accomplished by hybridization insertion of VH, VL, and sFv linker sequences onto a pET phagemid template containing the bL gene fused to the pelB leader sequence. Optimal soluble expression of L49-sFv-bL in E. coli was found to take place at 23 degrees C with 50 microM isopropyl beta-D-thiogalactopyranoside induction and the use of the nonionic detergent Nonidet P-40 for isolation from the bacteria. Construction and expression of a soluble form of the p97 antigen in Chinese hamster ovary cells allowed affinity-based methods for analysis and purification of the fusion protein. Surface plasmon resonance, fluorescent activated cell sorting, and Michaelis-Menten kinetic analyses showed that L49-sFv-bL retained the antigen binding capability of monovalent L49 as well as the enzymatic activity of bL. In vitro experiments demonstrated that L49-sFv-bL bound to 3677 melanoma cells expressing the p97 antigen and effected the activation of 7-(4-carboxybutanamido)cephalosporin mustard (CCM), a cephalosporin nitrogen mustard prodrug. On the basis of these results, L49-sFv-bL was injected into nude mice with subcutaneous 3677 tumors, and localization was determined by measuring bL activity. Tumor to blood conjugate ratios of 13 and 150 were obtained 4 and 48 h post conjugate administration, respectively, and the tumor to liver, spleen, and kidney ratios were even higher. A chemically produced L49-Fab'-bL conjugate yielded a much lower tumor to blood ratio (5.6 at 72 h post administration) than L49-sFv-bL. Therapy experiments established that well-tolerated doses of L49-sFv-bL/CCM combinations resulted in cures of 3677 tumors in nude mice. The favorable pharmacokinetic properties of L49-sFv-bL allowed prodrug treatment to be initiated 12 h after the conjugate was administered. Thus, L49-sFv-bL appears to have promising characteristics for site-selective anticancer prodrug activation.


Subject(s)
Antineoplastic Agents/pharmacokinetics , Immunoglobulin G/genetics , Prodrugs/pharmacokinetics , beta-Lactamases/genetics , Animals , Biotransformation , CHO Cells , Cloning, Molecular , Cricetinae , Enterobacter cloacae/genetics , Escherichia coli/genetics , Humans , Immunoglobulin G/pharmacology , Immunoglobulin G/therapeutic use , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasms, Experimental/therapy , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/pharmacology , Recombinant Fusion Proteins/therapeutic use , Tumor Cells, Cultured , beta-Lactamases/pharmacology , beta-Lactamases/therapeutic use
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