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[en] Background and purpose: Clinical studies indicate that patients with HPV/p16-associated head & neck squamous cell carcinoma (HNSCC) represent a subgroup with a better prognosis and improved response to conventional radiotherapy. Involvement of immune-based factors has been hypothesized. In the present study, we investigated radiation-induced differences in release of damage associated molecular patterns (DAMPs), cytokines and activation of dendritic cells (DCs) in HPV-positive and negative HNSCC cancer cell lines. Material and methods: Calreticulin (CRT) exposure was detected on cancer cell surface. ATP, HMGB1 and cytokines were measured in culture supernatants. Maturation marker CD83 surface exposure was determined on DCs after co-incubation with irradiated tumor cells. Results: There was no increase in DAMPs and cytokine profiles after radiation treatment and no difference between HPV+ and HPV− cell lines. The HPV/p16-positive SCC90 cells showed a trend for increased total CRT, HMGB1, and number of cytokines compared to all other cell lines. None of the irradiated cancer cell lines could affect DC maturation. Conclusions: Radiation treatment did not increase immunogenicity of HNSCC cell lines assessed by membrane CRT, ATP, HMGB1, cytokines production, and by activation of immature DCs. There was no difference between HPV-positive and HPV-negative cell lines.
[en] The effect of Paclitaxel (PAC), Epirubicin (EPR) and Tamoxifen (TAM) on ''3H-thymidine labelling index (''3H-TdR LI) of Ehrlich ascites tumor cells (EAT) was investigated in cultured. In the present study, an estrogen receptor positive ER(+) hyper diploid cell lines were studied. We used optimum doses of PAC, EPR and TAM (12 mg/ml, 12 mg/ml and 2 mg/ml, respectively). Cells were treated with these doses for 0, 4, 8, 16 and 32 hours. At the end of these periods, both control and treated cells were labelled for 5 mCi/ml 3H-thymidine for 30 minutes. The results showed that inhibition of DNA synthesis in cultured EAT cells were increased in the combined treatment of two drugs when compared to the treatment of a single drug (p<0.01). In the treatment of three drugs, however, this effect reached a maximum (p<0.001). As a result, PAC+EPR+TAM treatment's had a maximum synergistic effect at 4 hours treatment
[en] In this paper, I will not describe in detail the biochemical, biological, or oncogenetic aspects of tumor makers, but will limit my discussion to the clinical applications of tumor markers, and, in some instances, comment on some specific aspects or methodology. The biological characteristics of tumor makers can be observed in the differences between normal and cancerous cells. For clinical diagnostics, the improtant question is whether or not we can detect these changes by in vitro tests. By immunological means, we are able to detect changes on cell surfaces by measuring either differentiated antigens or cell specific antigens. (Author)
[en] Indolent B-cell lymphomas comprise a heterogeneous group of diseases. For patients with limited disease is local radiotherapy the treatment of choice.Watch and wait is the standard of care for patients with asymptomatic advanced stage disease. Standard first line treatment for symptomatic patients is chemo immunotherapy. The recent rediscovery of the „old“ chemotherapeutic agent bendamustin enhanced therapeutic options in indolent B-cell lymphomas. Thanks its favourable therapeutic index and effectiveness it is increasingly used in the in the first line and relapse setting as well. In patients with follicular lymphoma, the maintenance with rituximab after effective chemo immunotherapy is indicated. Earlier or later the relapse occurs in indolent lymphomas. It is the reason to have a wide variety of treatment options. In the last years we witness marked progress in the new drugs development. The new promising drugs are novel monoclonal antibodies, proteasome inhibitors, novel agents targeting a certain level of B-cell receptor signaling pathways, bcl-2 inhibitors or immunomodulatory agents. Novel agents may change our treatment approach to indolent lymphomas in the near future. (author)
[en] The possibilities to enhance the lethal effect of ionizing radiation on hypoxic cells by electron-affinic compounds have stimulated the investigations for finding new chemicals with radiobiological and pharmacological features as adequate as possible. On the other hand, the experimental studies and clinical trials had shown that the aerobic toxicity seems to be the major limiting factor in the use of large doses of radiosensitizers required to achieve significant therapeutic efficiency. The investigations in the present paper were attempted to join these two main directions of research and comprised the syntheses of new nitroheterocyclic compounds with potential radiosensitization properties and the knowledge of biochemical alterations involved in the producing of aerobic toxicity of radiosensitizers aiming to find practical solutions to enhance the efficiency of radiotherapy. Several newly synthesized compounds were tested for their radiosensitizing effect. The experiments carried out on hypoxic cells V 79 showed that only 1-(hydroxyethyl-2'-phosphate)-2-methyl-5-nitroimidazole, dipotassium salt displayed an enhancement ratio of 1.17 (at 8 mM), but lower than in case of parent compound, metronidazole (enhancement ratio = 1.53). It was shown that hypoxic cell radiosensitizers interfere with the cellular energy metabolism. These interferences were found dependent on the electron affinity of drugs. In addition, those radiosensitizers producing a decrease in oxygen consumption caused a supplementary oxygenation of both normal and tumour tissues. It is concluded that the improvement of therapeutic efficiency of radiosensitizers by reducing their aerobic toxicity might be achieved by diminishing their effects on the energy metabolism or by the stimulation of this metabolism and restoration of tissue redox equilibrium
[en] A new human tumour cell line (HX 165c) has been established from an epithelioid sarcoma presenting in a 28 year old male. The cells grew as an adherent monolayer with a doubling time of 38 h and had mainly epithelial morphology but with areas of mesenchymal-like cytoplasmic extensions. The mixed epithelial-mesenchymal phenotype was also apparent by intermediate filament analysis which showed reactivity to vimentin and keratin. The cells were tumorigenic in nude mice and aneuploid, possessing a mean chromosome number of 65. In vitro cloning determinations gave colony-forming efficiencies of 0.01% in an anchorage-independent soft agar assay and 34% in a monolayer anchorage-dependent assay. Cells were in the mid-range for radiosensitivity of human tumour cells (surviving fraction at 2 Gy of 0.39). Experiments utilising continuous low dose rate irradiation at 3.2 cGy min-1, showed the cells possessed only a small capacity to recover from radiation damage (dose reduction factor at 1% cell survival of 1.15 for 150 versus 3.2 cGy min-1). (author)
[en] Malignant uveal melanoma is the most common intraocular tumor in adults. The complications of this tumor are decrease of vision, loss of the eye and death from metastatic disease. Incidence is 5.1 per million. Diagnostics is based on complete ophthalmologic examination and imaging methods (ultrasound examination, magnetic resonance imaging). Therapeutic approach can be divided to eye globe sparing (radiotherapy, microsurgical resection) and radical methods (enucleation, orbital exoneration). Systemic therapy to prevent a metastatic spread has not been developed yet. Prognosis after metastatic spread (in 50% of patients) is poor. Progression to metastatic disease is related to some prognostic factors knowing that genetic abnormalities seem to be most reliable. (author)
[en] 81Rb is produced in high specific activity and yield by the reaction 79Br(α,2n)81Rb. The 81Rb is purified and absorbed on an ion-exchange column in a minigenerator, which allows the elution, at a rapid rate, of the /SUP 81m/Kr daughter in a biologically compatible, sterile solution. Applications of /sup 81m/Kr are described. Chemical binding in tumor cells is being studied and the use of /sup 134m/Cs for myocardial scanning is being evaluated. (U.S.)
[en] We sought to describe and compare material specific inflammatory and foreign body reactions after porcine liver embolization with spherical embolic agents. In 40 animals, superselective liver embolization was performed with four different spherical embolic agents of various sizes: 40-120 μm (Embozene, Embosphere), and 100-300 μm, 500-700 μm, and 700-900 μm (Embozene, Embosphere, Bead Block, and Contour SE, respectively). After 4 or 12 weeks, inflammatory reactions were evaluated microscopically according to the Banff 97 classification. For investigation of foreign body reactions, a newly designed giant cell score was applied. Banff 97 and giant cell scores closely correlated. At 4 weeks, small Embosphere particles (100-300 μm) had a significantly higher Banff 97 score than Embozene, Bead Block, and Contour SE of the corresponding size. After 12 weeks, the calculated differences were not statistically significant. Comparison between the 4-week results and the 12-week results revealed a statistically higher Banff 97 score for Embosphere 100-300 μm after 4 weeks than after 12 weeks (P = 0.02). The overall foreign body reaction was pronounced after embolization with smaller particles, especially in small Embosphere particles. Giant cell numbers with Embosphere 100-300 μm were statistically higher compared with the other materials of corresponding size (P < 0.0001). Inflammatory and giant cell reactions after embolization procedures depend on the embolic material. The overall inflammatory reaction was low. However, marked inflammation was associated with small Embosphere particles at 4 weeks, a finding that might be caused by the allogeneic overcoat. Correspondingly, giant cells indicating a foreign body reaction were more frequently associated with small particle sizes, especially after embolization with small Embosphere particles.