Colocalization of basic fibroblast growth factor and CD44 isoforms containing the variably spliced exon v3 (CD44v3) in normal skin and in epidermal skin cancers

Previous in vitro studies have shown CD44 isoforms containing the alternatively spliced exon v3 (CD44v3) to be modified with heparan sulphate (HS) and to bind HS-binding basic fibroblast growth factor (bFGF). Here, we demonstrate that exogenously added bFGF is also bound in vivo by CD44v3-positive keratinocytes in normal skin and by tumour cells in basal cell carcinoma and squamous cell carcinoma (SCC), two skin cancers of keratinocyte origin. bFGF binding and CD44v3 expression were colocalized in cultured human normal keratinocytes (HNK) and on the SCC cell line A431. By contrast, benign or malignant tumours of melanocyte origin failed to express CD44v3 and bound no bFGF. The bFGF binding to normal or transformed keratinocytes in vivo and in vitro was dependent on HS modification, as it was completely eliminated by pretreatment with heparitinase or by blocking with free heparin, whereas chondroitinase had no effect. In addition, specific removal of CD44v3 by antibody-induced shedding also diminished bFGF binding to keratinocytes. Furthermore, bFGF stimulated the proliferation of CD44v3-positive HNK and A431 in a dose-dependent fashion. This bFGF effect was again completely abolished by heparitinase or free heparin, but not by chondroitinase. In aggregate, our results suggest that a function of HS-modified CD44 isoforms such as CD44v3 in skin is to present the HS-binding growth factor bFGF, thereby stimulating the proliferation of normal or transformed keratinocytes.     

Benign clear cell tumour of the lung--intermediate filament typing as a tool in differential diagnosis

A case of a benign clear cell ('sugar') tumour of the lung in a 61-year-old woman is presented. Characteristic routine histological features are provided and problems concerning differential diagnosis are discussed. Immunohistochemical stainings for the intracytoplasmatic intermediate filament proteins keratin and vimentin in our patient suggest a mesenchymal origin for this rare pulmonary neoplasm, and provide useful diagnostic aid in inconclusive cases.     

Intracerebral tuberculomas in a pregnant Somalian woman

A pregnant Somalian woman aged 28 years, in the Netherlands for the last five years, suffered from a progressive hemiparesis, epilepsia, behavioural problems and low fever. Brain MRI showed multiple lesions with contrast enhancement. Extensive serologic and parasitologic tests on serum and cerebrospinal fluid did not disclose any cause. A brain biopsy revealed only necrosis, but bacterial culture and polymerase chain reaction (PCR) supplied the diagnosis of 'tuberculosis'. PCR on the cerebrospinal fluid remained negative. In the meantime the chest X-ray showed miliary tuberculosis and a spine MRI thoracic spondylodiscitis and a large paravertebral abscess. Subsequently the patient was treated successfully with tuberculostatic agents. Her healthy child which was born by caesarean section was treated with the tuberculostatic agents as well.     

Regression of invasive thymoma following corticosteroid therapy

A case of invasive thymoma is presented showing tumour regression after palliative treatment with prednisone. Moderate doses of prednisone resulted in a longtime palliation via remarkable anti-tumour effect. The literature of corticosteroid responses of thymomas is reviewed.     

Treatment outcome and toxicity of intensity-modulated (chemo) radiotherapy in stage III non-small cell lung cancer patients

ABSTRACT: PurposeThe aim of this retrospective cohort study was to assess treatment outcome, and acute pulmonary and esophageal toxicity using intensity modulated (sequential/concurrent chemo)radiotherapy (IMRT) in locally advanced stage III non-small cell lung cancer (NSCLC).Methods and materialsEighty-six patients with advanced stage NSCLC, treated with either IMRT only (66 Gy) or combined with (sequential or concurrent) chemotherapy were retrospectively included in this study. Overall survival and metastasis-free survival were assessed as well as acute pulmonary and esophageal toxicity using the RTOG Acute Radiation Morbidity Scoring Criteria. RESULTS: Irrespective of the treatment modality, the overall survival rate for patients receiving 66 Gy was 71% (+/-11%; 95% CI) after one year and 56% (+/-14%) after two years resulting in a median overall survival of 29.7 months. Metastasis-free survival was 73% (+/-11%) after both one and two years. There were no statistically significant differences between the treatment groups. Treatment related esophageal toxicity was significantly more pronounced in the concurrent chemoradiotherapy group (p = 0.013) with no differences in pulmonary toxicity. CONCLUSIONS: This retrospective cohort study in advanced non-small cell lung cancer patients shows that IMRT is an effective technique with acceptable acute toxicity, also when (sequentially or concomitantly) combined with chemotherapy.     

Toll-like receptor and IL-12 signaling control susceptibility to contact hypersensitivity

Allergic contact hypersensitivity (CHS) is a T cell–mediated inflammatory skin disease. Interleukin (IL)-12 is considered to be important in the generation of the allergen-specific T cell response. Loss of IL-12 function in IL-12Rβ2–deficient mice, however, did not ameliorate the allergic immune response, suggesting alternate IL-12–independent pathways in the induction of CHS. Because exposure to contact allergens always takes place in the presence of microbial skin flora, we investigated the potential role of Toll-like receptors (TLRs) in the induction of CHS. Using mice deficient in TLR4, the receptor for bacterial lipopolysaccharide (LPS), IL-12 receptor (R) β2, or both, we show that the concomitant absence of TLR4 and IL-12Rβ2, but not the absence of TLR4 or IL-12Rβ2 alone, prevented DC-mediated sensitization, generation of effector T cells, and the subsequent CHS response to 2,4,6-trinitro-1-chlorobenzene (TNCB), oxazolone, and fluorescein isothiocyanate. Introduction of the TLR4 transgene into the TLR4/IL-12Rβ2 mutant restored the CHS inducibility, showing a requirement for TLR4 in IL-12–independent CHS induction. Furthermore, the concomitant absence of TLR2 and TLR4 prevented the induction of CHS to TNCB in IL-12–competent mice. Finally, CHS was inducible in germ-free wild-type and IL-12Rβ2–deficient mice, but not in germ-free TLR4/IL-12Rβ2 double deficient mice, suggesting that the necessary TLR activation may proceed via endogenous ligands.     

Newcastle disease virus infection induces B7-1/B7-2-independent T-cell costimulatory activity in human melanoma cells

Viral oncolysates of Newcastle disease virus (NDV) have been widely used for the treatment of malignant melanoma. Apparently, this nononcogenic and apathogenic paramyxovirus can alter the immunogenicity of tumor cells. To determine the influence of NDV infection on a tumor-specific T-cell response on a functional level, we used autologous primary melanoma cells infected with the NDV-strain Ulster. Therefore, melanoma cells and tumor-infiltrating lymphocytes were prepared from a freshly resected tumor, and tumor-infiltrating lymphocytes were subjected to limited dilution cloning. Proliferation assays of the T-helper cell clone sTS3 (CD4+) showed that the T-cell clone was rendered nonreactive against its autologous major histocompatibility complex II+, B7-1/B7-2- melanoma SMS, even remaining unresponsive to subsequent stimulation by interleukin-2. NDV infection of the SMS melanoma cell line not only completely restored the proliferative response of sTS3 to SMS, comparable with stimulation by cross-linking of anti-CD3/anti-CD28 monoclonal antibodies, but also inhibited the induction of anergy. Electrophoretic mobility shift assays of sTS3 cell lysates revealed the induction of the CD28-responsive complex by coincubation with NDV-infected melanoma cells. Because the induction of this complex of nuclear proteins shows specificity for the activation of the CD28 pathway but functional B7-1/B7-2 expression was not detectable on SMS melanoma cells at any timepoint, we propose the induction of a costimulatory factor different from B7 by NDV viral proteins.     

Prevention of chemotherapy-induced febrile neutropenia by prophylactic antibiotics plus or minus granulocyte colony-stimulating factor in small-cell lung cancer: a Dutch Randomized Phase III Study.

PURPOSE: Febrile neutropenia (FN) is a major complication of chemotherapy. Antibiotics as well as granulocyte colony-stimulating factor (G-CSF) are effective in preventing FN. This multicenter randomized phase III trial determines whether the addition of G-CSF to antibiotic prophylaxis can further reduce the incidence of FN in patients with small-cell lung cancer (SCLC) at the risk of FN. PATIENTS AND METHODS: Patients (N = 175) were stratified for stage of disease, performance status, age, and prior chemotherapy treatment, and were randomly assigned for treatment with cyclophosphamide, doxorubicin, and etoposide (CDE), followed by prophylactic antibiotics alone (ciprofloxacin and roxithromycin) or by antibiotics in combination with G-CSF on days 4 to 13. RESULTS: In cycle 1, 20 patients (24%) in the antibiotics group developed FN compared with nine patients (10%) in the antibiotics plus G-CSF group (P = .01). In cycles 2 to 5, the incidences of FN were practically the same in both groups (17% v 11%). Only the treatment parameters (odds ratio, 0.33; 95% CI, 0.14 to 0.78) and age (1.067 per year; 95% CI, 1.013 to 1.0124) were related to the probability of FN in cycle 1. CONCLUSION: Primary G-CSF prophylaxis added to primary antibiotic prophylaxis is effective in reducing FN and infections in SCLC patients at the risk of FN with the first cycle of CDE chemotherapy. For patients with similar risk of FN, the combined use of prophylactic antibiotics plus G-CSF can be considered, specifically in the first cycle of chemotherapy.     

Targeting dendritic cells with CD44 monoclonal antibodies selectively inhibits the proliferation of naive CD4+ T-helper cells by induction of FAS-independent T-cell apoptosis

CD44 is a multifunctional adhesion molecule that has been shown to be a costimulatory factor for T-cell activation in vitro and in vivo. The aim of the present study was to expand these findings by characterizing the role of CD44 during dendritic cell (DC) antigen presentation to naive, resting T cells. Certain monoclonal antibodies (mAbs) directed against all CD44 isoforms (pan CD44), or against the epitope encoded by the alternatively spliced exon v4 (CD44v4), dose-dependently inhibited the capacity of murine DC to induce proliferation of naive alloreactive T cells. Preincubation of the T cells or DC with these CD44 mAbs revealed that the effect was dependent upon mAb binding to DC, but not to T cells. DC treated with anti-pan CD44 and anti-CD44v4 mAbs induced CD4+ T-cell apoptosis, as shown by annexin V staining and TdT-mediated biotin-dUTP nick-end labelling (TUNEL) assays. However, CD4+ T-cell apoptosis was not dependent on the Fas/Fas ligand (Fas/FasL) system, as DC from FasL-deficient (Gld) mice and T cells from Fas-deficient (Lpr) mice were still susceptible to apoptosis induced by CD44-treated DC. To investigate whether CD44 treatment of DC affects early T-cell/DC interactions, time-lapse video microscopy was performed using peptide-specific T cells from T-cell receptor (TCR) transgenic mice. Interestingly, calcium signalling in CD4+ T cells was significantly diminished following interaction with CD44 mAb-treated DC, but this was not observed in CD8+ T cells. Taken together, we found that perturbation of distinct epitopes of CD44 on DC interfere with early Ca2+ signalling events during the activation of CD4+ T cells, resulting in T-cell apoptosis.     

Human dendritic cells are a physiological source of the chemotactic arachidonic acid metabolite 5-oxo-eicosatetraenoic acid

OBJECTIVE: The arachidonic acid metabolite, 5-oxo-eicosatetraenoic acid (5-oxo-ETE), is a potent chemotaxin for neutrophils and eosinophils. The aim of this study was to identify physiological conditions and stimulators of 5-oxo-ETE synthesis, because no such conditions have yet been identified. METHODS: Human neutrophils and monocyte-derived dendritic cells were prepared and 5-oxo-ETE synthesis analyzed using precolumn/reversed-phase HPLC under different conditions and with several physiological and unphysiological stimuli. RESULTS: Incubation of neutrophils with 5-hydroxyeicosatetraenoic acid (5-HETE) resulted in the synthesis of about 3.4 nM 5-oxo-ETE per 10(6) cells in 1 ml under optimal conditions. The synthesis was enhanced about 8-fold with the unphysiological stimuli calcium ionophore A23187 and phorbol 12-myristate 13-acetate (PMA). No significant effect was observed with different physiological activators. Under optimal conditions, human dendritic cells produced about 50 nM 5-oxo-ETE per 10(6) cells in 1 ml. The synthesis could be increased with PMA and A23187 by about 50%. Again, no effect could be observed with physiological agents for dendritic cells such as complement fragment C5a, platelet activating factor, N-formyl peptides and interleukin-5. CONCLUSIONS: These data identified dendritic cells as the only yet known physiological source of relevant amounts of 5-oxo-ETE. This suggests a regulatory function of dendritic cells in the induction of inflammatory neutrophil and eosinophil infiltration caused by 5-oxo-eicosatetraenoic acid.