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Hybrid cell vaccines of autologous tumour cells fused with allogenic dendritic cells (DC) combine the tumour's antigenicity with the immune-stimulatory capacity of mature dendritic cells and allogenic MHC class II molecules to activate T cell help and induce tumour-specific cytotoxic T cells. This concept was tested in a clinical trial with melanoma stage III and IV patients. Seventeen patients were evaluated: one experienced complete, one partial response and six stable disease with long survival times. Eleven of fourteen patients, clinical responders and non-responders alike, mounted high-frequency T cell responses to various tumour-associated antigens. Failing clinical responses correlated with loss of antigenicity. Ler mais
Hybrid cell vaccination was developed as therapeutic approach that aims at stimulating tumor-specific cytotoxic T-cell responses in cancer patients using hybrids of autologous tumor and allogeneic dendritic cells. We tested this concept and the efficacy of the vaccines in inducing clinical and immunologic responses in a clinical trial with melanoma stage III and IV patients. Of the 17 patients evaluated, 1 experienced a complete response, 1 a partial response and 6 stable disease with remarkably long survival times. In 11 of 14 patients analyzed, high-frequency T-cell responses to various tumor-associated T-cell epitope were induced and detectable in the peripheral blood. These immune responses were detected in clinical response patients as well as nonresponders. Failures of clinical responses in all the cases investigated correlated with loss of antigen expression and presentation. Hybrid cell vaccination thus proves effective in inducing tumor-specific T-cell responses in cancer patients. Ler mais
This study was performed to detect circulating melanoma cells in peripheral blood using a novel method based on magnetic-activated cell separation (MACS) followed by a nested reverse transcriptase-polymerase chain reaction (RT-PCR) for tyrosinase and MART-1 mRNA. Samples to be tested were enriched for tumour cells either by isolating melanoma cells using two anti-melanoma antibodies (MART-1 and HMB-45) or by CD45 depletion of the non-melanoma cell fraction. The tumour cell-enriched fractions were subjected to mRNA isolation using oligo-deoxythymidylate (oligo-dT) magnetic beads followed by a nested RT-PCR. Sensitivity was assessed by spiking experiments and compared with a commonly used total RNA isolation system previously established in our department. Positive isolation of melanoma cells showed insufficient sensitivity, whereas negative isolation by depletion of leukocytes showed a detection limit of at least one melanoma cell per millilitre of whole blood. In further experiments, the depletion assay was applied to 25 peripheral blood samples of melanoma patients. The preliminary data obtained from the new method indicate a comparable detection rate to the established total RNA extraction method. However, not all the results were concordant. Therefore, future experiments need to be performed with a statistically greater number of patients. Ler mais
There are no accepted second-line therapeutic options in patients with disseminated melanoma. We evaluated toxicity and efficacy of a combination therapy with cisplatin and carboplatin. Ler mais
We report 2 patients who developed melanoma or melanoma metastases in radiation fields 6 and 43 years after radiation therapy, respectively. One of the patients had received adjuvant hyperfractionated photon therapy for Ewing sarcoma, while the other patient had received X-ray therapy for a hemangioma. While postradiation secondary cancers with a long latency period are not uncommon, the development of melanoma is exceedingly rare. Ler mais
