PubMed Health⌕ Search

Biomedical subjects

I G Schmidt-Wolf

Publications and source records attributed to I G Schmidt-Wolf.

At least 19 recordsLinked to original sources
PubMed2006

[Adjuvant and palliative chemotherapy of colorectal cancer in Germany outside controlled trials].

BACKGROUND AND OBJECTIVE: Colorectal cancer is the second most common malignant tumour in Germany with an unfavorable prognosis especially in a locally advanced or metastasizing stage. Although adjuvant and palliative chemotherapy significantly improve 5-year survival, consensus recommendations have in the past been inadequately transformed into clinical practice. It was the aim of this study to analyse the implementation of existing guidelines in a cohort from a defined area of Germany. PATIENTS AND METHODS: In a multicentre study done between January 2000 and January 2002, tumour stage, primary care, adjuvant or palliative chemotherapy and follow-up of 444 patients (216 males, 228 females) with newly diagnosed colorectal cancer were recorded. RESULTS: 301 patients had colonic and 143 patients rectal cancer. The median age at diagnosis was 65 11.3 years. 36 of 96 (38%) patients with stage II colon cancer and 66 of 87 (76%) with stage III disease received adjuvant chemotherapy. 8 of 51 (16%) patients with rectal cancer stage II and 22 of 38 (58%) patients with stage III underwent adjuvant radio- and chemotherapy. The 68 of 84 (81%) patients with stage IV CRC who received palliative chemotherapy were given almost exclusively 5-FU monotherapy. Initial or sequential combination chemotherapy with oxaliplatin or irinotecan were performed in only 24 of 84 (29%) patients. CONCLUSIONS: Stage III colon cancer was predominantly treated according to the existing standard guidelines. In contrast combined radio- and chemotherapy for rectal cancer stage II and III was only performed in one third of the patients, another third receiving neither adjuvant radiation nor chemotherapy. Initial combined or sequential combined chemotherapy for metastasizing colorectal cancer was rarely performed.

Adult↗
PubMed2005

Neuropsychological outcome after chemotherapy for primary CNS lymphoma: a prospective study.

BACKGROUND: Combined radio- and chemotherapy for primary CNS lymphoma (PCNSL) is associated with a considerable risk of long-term neurotoxicity. The impact of high-dose methotrexate (MTX)-based chemotherapy alone on cognition and quality of life (QOL) is controversial. OBJECTIVE: To assess the impact of the tumor itself and its treatment with high-dose MTX-based chemotherapy on long-term cognition and QOL in patients with PCNSL. METHODS: Prospective neuropsychological examinations and MRI were performed in patients with PCNSL who were in complete remission for more than 12 months after completion of chemotherapy. A QOL assessment was performed at long-term follow-up. RESULTS: Twenty-three patients were eligible. The median follow-up period was 44 months after diagnosis. In long-term follow-up, 22 (95%) of 23 patients showed either preserved or improved cognitive functions as compared with pretreatment and immediate posttreatment baseline assessment. One patient showed an isolated decline in psychomotor speed. Eleven (48%) of 23 patients displayed at least mild cognitive deficits at long-term follow-up not related to therapy. Nineteen (83%) of 23 patients reported a good QOL. MRI revealed confluent white matter abnormalities in eight patients that were not associated with cognitive decline. CONCLUSION: In patients with primary CNS lymphoma (PCNSL) treated with a methotrexate (MTX)-based chemotherapy, no gross cognitive decline has to be expected as a long-term treatment effect. MTX-induced white matter changes apparent on MRI are not inevitably associated with cognitive impairment. Nevertheless, a substantial fraction of patients with PCNSL retain cognitive deficits as a residual symptom of the tumor.

Adult↗
PubMed2005

Population-based registration of unselected colorectal cancer patients: five-year survival in the region of Bonn/Rhine-Sieg, Germany.

INTRODUCTION: Epidemiological data of colorectal cancer are sparse and often incomplete. Therefore, we initiated a population-based examination of five-year survival of colorectal cancer patients. METHODS: For complete registration, diagnosis and tumour stage of all patients in the region of Bonn/Rhine-Sieg were assessed independently according to reports of medical practitioners and pathologists. Each patient was followed by a standardised questionnaire during a period of five years. RESULTS: Between June and November, 1994 348 patients were registered. Median age at diagnosis was 69 years for males (n = 160) and 72 years for females (n = 188). According to the UICC classification 18, 26, 23 and 26 % had stage I-IV tumours, respectively; the tumour stage remained unclear in 7 %. Adjuvant (radio)-chemotherapy was indicated in 89 patients, but only 49 % of these were treated. Five-year overall survival (OS) and relative overall survival were 41 and 54 %, respectively. Although disease-free survival (DFS) was significantly better for early stage colorectal cancer, OS did not differ significantly between stage I and stage III tumours. Young patients diagnosed before the age of 50 had a significantly lower DFS. These data were comparable with other European countries but were lower than data reported in the USA. DISCUSSION: The high rate of patients with stage IV colorectal cancer and the low proportion of patients receiving adjuvant (radio)-chemotherapy according to international or national consensus recommendations were disappointing. Although data were comparable with other European countries more efforts are necessary to establish effective screening programs for asymptomatic patients and to increase the willingness for standardised adjuvant treatment.

Adult↗
PubMed2001

Clostridium difficile infection in patients with neutropenia.

Clostridium difficile is the most important cause of nosocomial infectious diarrhea. The importance of C. difficile-associated diarrhea (CDAD) has been poorly investigated in patients with neutropenia who have hematologic malignancies. A retrospective chart review of all patients treated in the leukemia ward of a university medical center during 1991-2000 determined that 875 courses of myelosuppressive chemotherapy were administered. CDAD occurred in 7.0% of all cycles. In 8.2% of the patients, severe enterocolitis developed. Two patients died while they had diarrhea. However, in no patient was C. difficile infection clinically considered to be the primary cause of death. The response rate to oral metronidazole was 90.9%. These data indicate that C. difficile infection is not rare and should be suspected whenever a hospitalized patient with neutropenia develops diarrhea. Oral metronidazole can be recommended as initial drug of choice for treatment of patients with neutropenia who have hematologic malignancies and CDAD.

Adolescent↗
PubMed2001

Therapeutic vaccination against metastatic carcinoma by expression-modulated and immunomodified autologous tumor cells: a first clinical phase I/II trial.

Therapeutic vaccination of tumor patients with cytokine gene-transfected tumor cells leads to tumor regression in animal models but has so far not resulted in significant clinical benefit. We and others demonstrated that tumor cells transfected to mediate overexpression of a cytokine gene activate immunologic effector cells for an improved proliferation rate and significantly higher antitumoral cytotoxic activity. Here, we performed a pilot study of therapeutic vaccination in patients with metastatic disease. Autologous tumor cells were simultaneously transfected with novel minimalistic, immunogenically defined, gene expression constructs (MIDGE) for overexpression of the two cytokines interleukin 7 (IL-7) and GM-CSF and newly designed double stem-loop immunomodulating oligodeoxyribonucleotides (d-SLIM) as a Th1-promoting and NK cell-stimulating adjuvant. Transfection was performed ex vivo by ballistomagnetic gene transfer. Patients received four subcutaneous injections of at least 1 x 10(6) of their expression-modulated and immunomodified autologous tumor cells. Ten patients have been enrolled in the study protocol. In all patients no adverse effects could be detected. IL-7 and interferon gamma levels were elevated in the serum of the patients after treatment. Interestingly, cytotoxicity of patient-derived PBLs increased significantly during treatment. All 10 patients had progressive disease when entering our protocol. One complete, one partial, and one mixed response with progression of abdominal metastases and regression of lung metastases were observed. Two patients showed a stable disease after treatment and five patients remained in progressive disease. Our observations confirm the capability of autologous expression-modified and immunomodulated tumor cell vaccines to stimulate a strong immune response in patients with metastatic cancer even in the presence of a large tumor burden.

Aged↗
PubMed2001

Resistance of pancreatic carcinoma cells is reversed by coculturing NK-like T cells with dendritic cells pulsed with tumor-derived RNA and CA 19-9.

Immunization with defined tumor antigens is limited to the small number of cancers in which specific tumor antigens have been defined but insufficient tumor material is available to produce an antitumor vaccine. In this study, we investigated whether pulsing dendritic cells (DC) using a liposomal transfer technique with a pancreatic tumor cell line-derived RNA can effectively activate NK-like T cells and tumor immunity. Pulsed DC were cocultured with NK-like T cells, i.e., CD3+CD56+ cells, as immunologic effector cells. Target cells resistant to NK-like T-cell-mediated lysis were used. Total tumor-derived RNA transfected into DC was found to completely reverse tumor cell resistance. Total tumor RNA transfection (30 microg) was found to be superior to poly(A)(+) RNA transfection (5 microg) in inducing NK-like T lymphocytes. Interestingly, additional pulsing of DC with the CA 19-9 peptide in a CA 19-9-positive cell line further increased the sensitivity of pancreas carcinoma cells to NK-like T cells. Treatment of tumor RNA with RNase completely blocked the effect of RNA-transfected DC on NK-like T cells, suggesting that intact tumor-derived RNA is needed for reversal of tumor cell resistance. In conclusion, coculture of NK-like T cells with DC transfected with pancreatic tumor cell line-derived RNA reverses pancreatic tumor cell resistance by directly triggering NK-like T lymphocytes.

CA-19-9 Antigen↗
PubMed2001

A novel minimal-size vector (MIDGE) improves transgene expression in colon carcinoma cells and avoids transfection of undesired DNA.

Viral and plasmid vectors may cause unwanted immunological side effects resulting from the expression of nontherapeutic genes contained in their sequence. Furthermore, replication-defective viral vectors carry the potential risk of recombination with wild-type viruses or activation of oncogenes. A new vector type for minimalistic, immunologically defined gene expression (MIDGE) may overcome these problems. MIDGE is a minimal-size gene transfer unit containing the expression cassette, including promoter, gene, and RNA-stabilizing sequence, flanked by two short hairpin oligonucleotide sequences. The resulting vector is a small, linear, covalently closed, dumbbell-shaped molecule. DNA not encoding the desired gene is reduced to a minimum. Here, we transfected colon carcinoma cell lines using cationic lipid, cationic polymer, and electroporation with several MIDGE vectors and corresponding plasmids containing transgenes encoding enhanced green fluorescent protein (eGFP) and human interleukin-2 (hIL-2). Transfection efficiency as measured qualitatively and quantitatively with eGFP was found to be comparable for both vector types. However, hIL-2 secretion and eGFP expression were approximately two- to fourfold higher in most cells transfected with these transgenes using MIDGE vectors compared to the plasmid control. This report demonstrates the advantages of this new vector type and its prospects for ex vivo gene therapy studies.

Cations↗
PubMed2001

Littoral cell angioma as a rare cause of splenomegaly.

A 58-year-old, otherwise healthy man presented with a sudden onset of watery diarrhea. A pseudomembranous colitis due to antibiotics was identified as the cause of the diarrhea. Enlargement of the spleen was detected during the evaluation. The enlarged, plump spleen (20 cm long, 7.1 cm wide) had multiple nodules that differed in size from 1 to 8 cm. Neither clinical nor other symptoms of an underlying malignant disease could be detected. Because the signs were of little diagnostic value we arranged a splenectomy, which showed a littoral cell angioma (LCA) to be the cause of splenomegaly. In addition to the case report, we have reviewed the literature, clinical manifestations, differential diagnosis, special gross and microscopic pathological findings, and the location of this benign vessel tumor in the pathology of the spleen.

Hemangioma↗
PubMed2001

Small bowel obstruction in acute myelogenous leukemia: stenosis or paralysis?

We describe a patient with acute myelogenous leukemia who suffered a small bowel obstruction on the second day of chemotherapy. The patient had to be operated immediately, and the terminal ileum and a part of the colon was removed. The resected specimen showed leukemic infiltration (chloroma) of the bowel with marked atrophy of the muscular layer. However, there was no complete stenosis. For this reason we believe that the reason for the acute abdominal symptoms on the second day of chemotherapy could be paralysis of the bowel due to muscular atrophy.

Abdominal Pain↗
PubMed2001

Transfection of dendritic cells (DCs) with the CIITA gene: increase in immunostimulatory activity of DCs.

Dendritic cells (DCs) are the major antigen-presenting cells. They are able to present tumor antigens to immunologic effector cells. MHC class II molecules on DC surfaces play an important role in priming effector cells against tumor cells and their antigens. The transactivator CIITA (MHC class II transactivator) is a non-DNA-binding transactivator, which regulates the expression of MHC class II, HLA-DM, and invariant chain and behaves as a master controller of constitutive and inducible MHC class II gene activation. Here, we transfected DCs with the CIITA gene using a novel transfection technique. The vector system consisted of a plasmid bound to an adenovirus via poly-L-lysine, which is covalently bound to a UV-irradiated adenovirus. After transfection, expression of MHC class II on DCs increased from 27% to 75% on day 2 after transfection. Transfected DCs were co-cultured with immunologic effector cells. Cytotoxicity of effector cells against tumor cells increased after co-culture with transfected DCs to 63% compared to 15% with effector cells co-cultured with irrelevantly transfected DCs (P=.037). This effect was dependent on the timing and period of co-culture. In conclusion, transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs. We can further conclude that DCs could be efficiently transfected with the CIITA gene. Transfection of DCs led to an increase in antitumoral immunostimulatory capacity of DCs and may have a major impact on immunotherapeutic protocols for patients with cancer.

Adenoviridae↗
PubMed2001

Effects of adenoviral wild-type p53 gene transfer in p53-mutated lymphoma cells.

The present study assessed the role of adenoviral vector-mediated wild-type p53 gene transfer in B lymphoma cells. Deficiency of p53-mediated cell death is common in human cancer contributing to both tumorigenesis and chemoresistance. Lymphoma cells are being considered as suitable targets for gene therapy protocols. Recently, we reported an adenoviral protocol leading to highly efficient gene transfer to B lymphoma cells. All lymphoma cell lines (n=5) tested here showed mutations in the p53 gene locus. The aim of this work was to transduce lymphoma cells with the wild-type p53 gene. Using this protocol, 88% of Raji, 75% of Daudi, and 45% of OCI-Ly8-LAM53 cells were transfected with the reporter gene green fluorescent protein at a multiplicity of infection of 200. The expression of green fluorescent protein in CA46 and BL41 cells was 27% and 42%, respectively. At this multiplicity of infection, growth characteristics of lymphoma cell lines were not changed significantly. In contrast, cells transduced with wild-type p53 gene showed an inhibition of proliferation as well as an increase in apoptosis. Cell loss by apoptosis after p53 gene transfer was up to 40% as compared to transduction with an irrelevant vector. In addition, we determined the effects of DNA damage produced by the DNA topoisomerase II inhibitor etoposide on wild-type p53 transfected lymphoma cells. In Ad-p53-transfected Raji cells, treatment with the drug resulted in a marked increase of cell loss in comparison to Ad-beta-Gal-transfected cells (45% vs. 77%). Interestingly, performing cytotoxicity studies, we could show an increased sensitivity of Raji and Daudi cells against immunological effector cells. In conclusion, transduction of wild-type p53 into lymphoma cells expressing mutated p53 was efficient and led to inhibition of proliferation and increase in apoptotic rate in some cell lines dependent on p53 mutation. This protocol should have an impact on the use of lymphoma cells in cancer gene therapy protocols.

Adenoviridae↗
PubMed2001

Influence of cytokines, monoclonal antibodies and chemotherapeutic drugs on epithelial cell adhesion molecule (EpCAM) and LewisY antigen expression.

MoAbs against tumour-associated antigens (TAA) may be useful for the treatment of colorectal cancer. Since an increased expression of TAA may lead to enhanced antibody-dependent cellular cytotoxicity we examined whether the cytokines IL-2, IL-4, IL-6, IL-10, IL-12, interferon-alpha (IFN-alpha), IFN-gamma, granulocyte-macrophage colony-stimulating factor, macrophage colony-stimulating factor and tumour necrosis factor-alpha can influence EpCAM and LewisY expression on the surface of the colorectal carcinoma cell lines HT29, LoVo and SW480. We found that only IFN-alpha increased significantly whereas IL-4 decreased both EpCAM and LewisY expression. IFN-gamma significantly increased LewisY expression only. When tumour cells were treated with MoAb, the LewisY-specific MoAb BR55-2 down-regulated LewisY antigen expression, whereas MoAb 17-1A, which binds to EpCAM, up-regulated this TAA after 3 days of culture. The cytokines IFN-alpha or IFN-gamma combined with MoAb 17-1A enhanced further slightly the expression of EpCAM. In additional experiments with chemotherapeutic drugs commonly used for the treatment of colorectal cancer, we found that 5-fluorouracil, mitomycin-C and oxaliplatin up-regulated EpCAM and LewisY antigen expression. Raltitrexed enhanced LewisY and down-regulated EpCAM expression, whereas CPT-11 had no influence at all. The highest expression for EpCAM on HT29 cells was achieved by the combination of IFN-alpha, 5-fluorouracil and MoAb 17-1A. Our results may be useful for defining combinations of biological and chemotherapeutic drugs for the treatment of colorectal cancer. Further trials should evaluate to what extent these combinations enhance antibody-dependent cellular cytotoxicity.

Adjuvants, Immunologic↗
PubMed2001

Severe abdominal infections in neutropenic patients.

Abdominal infections are an important cause of morbidity and mortality in neutropenic patients. We present a retrospective series of 16 patients, mostly with acute leukemia, who developed severe abdominal infections during chemotherapy-induced neutropenia between 1991 and 1997. The frequency among patients with acute leukemia was 2.35% (13 of 553). Thirteen patients presented with enterocolitis and 3 patients presented with cholecystitis. Eight patients died. Bacteremia was present in 6 patients, 4 patients suffered from proven or strongly suspected fungal infections, and 1 patient suffered from cytomegalovirus infection. Early surgical management was required in a patient with intestinal obstruction, whereas other patients could be managed conservatively. Two patients with acute cholecystitis were treated with antibiotics until the end of neutropenia and then were resected. Severe abdominal injections in neutropenic patients, which are often fatal, were caused by nonbacterial microorganisms in one-fourth of the cases and could be managed conservatively in most instances.

Abdomen↗
PubMed2001

Current clinical and laboratory strategies to augment the efficacy of immunotherapy in multiple myeloma.

Multiple myeloma is still an incurable, lethal disease for the vast majority of patients. Myeloablative chemotherapy combined with autologous or allogeneic hematopoietic stem cell transplantation only partially met the great expectations initially set in its efficacy and is associated with a high level of toxicity. However, the considerable progress in understanding the biology of multiple myeloma led to the development of promising molecular therapies. Numerous immunotherapy-based approaches are currently evaluated in clinical trials. Moreover, remarkable progress has been achieved in gene therapy during the last decade, and the repertoire of gene transfer techniques can be expected to improve continuously. Gene transfer is increasingly applied in biological therapies in multiple myeloma. This article reviews the currently applied clinical and laboratory strategies to augment the efficacy of immunotherapy in multiple myeloma and aims to define its perspectives in multimodality treatment of multiple myeloma.

Combined Modality Therapy↗
PubMed2001

Enhanced lytic activity of cytokine-induced killer cells against multiple myeloma cells after co-culture with idiotype-pulsed dendritic cells.

BACKGROUND AND OBJECTIVES: There are numerous reports of in vitro and in vivo usage of dendritic cells (DC) pulsed with idiotype, the tumor-specific antigen of multiple myeloma (MM), for immunotherapy of MM. Data suggest that not only T-cells, but also the innate immune system reacts against MM. Here, we examined the cytotoxic activity of cytokine-induced killer (CIK) cells against myeloma cells. This heterogeneous effector population consists of T-, NK- and NKT-cells. DESIGN AND METHODS: CIK cells generated from buffy coats or blood from patients with MM were co-cultured with autologous idiotype-pulsed DC. The cytotoxic activity was investigated in lactate dehydrogenase release assays against cell lines or autologous CD138 positive cells from bone marrow. RESULTS: CIK cells were able to lyse MM cells at low effector to target ratios. This effect was significantly enhanced by co-culturing with specifically pulsed DC (83.8% lysis at an effector to target ratio of 16:1). Using an interferon-g secreting MACS separation assay, the cytotoxic activity of CIK cells was enhanced to maximal lysis at the lower effector to target ratio of 5:1. High cytotoxic activity was also shown in a completely autologous setting against enriched CD138+ cells from a patient with MM (54.4% lysis at an effector to target ratio of 6:1). Interestingly, there was no cytotoxic activity against the CD138- fraction of the bone-marrow. INTERPRETATION AND CONCLUSIONS: Using a heterogeneous population of effector cells, we were able to activate the innate and the adoptive immune-system against myeloma cells. CIK cells showed high lytic activity against MM cells, which could be enhanced by co-culturing with antigen-specific pulsed DC.

Antigens, Neoplasm↗
PubMed2000

Primary CNS lymphoma: clinical presentation, pathological classification, molecular pathogenesis and treatment.

Primary CNS lymphomas (PCNSL) represent malignant non-Hodgkin's B cell lymphomas, which are confined to the central nervous system. They show a dramatic increase in frequency in the immunocompromised as well as in the immunocompetent population. Recent studies have identified germinal center B cells as the cellular origin of PCNSL; however, the details of their molecular pathogenesis still remain to be elucidated. Treatment recommendations are not clearly established. Radiotherapy (RT) is efficient in terms of tumor response, but not curative. Median survival after RT alone is about 1 year. According to the results of uncontrolled studies the combination of RT and chemotherapy based on high-dose methotrexate (HD-MTX) is most efficient in terms of survival rates. However, long-term neurotoxicity overshadows treatment efficacy, especially in patients over 60 years of age. The authors favor the systematic evaluation of chemotherapy alone with protocols including HD MTX, because unicenter results are promising in terms of both survival as well as quality of life in long term survivors.

Central Nervous System Neoplasms↗
PubMed2000

Comparison of non-viral transfection methods in melanoma cell primary cultures.

Melanoma primary cultures were transiently transfected via electroporation and lipofection for comparison. Transfection efficiency was superior with electroporation (58+/-9%) as compared to lipofection (23+/-9%) as determined by enhanced green fluorescent plasmid (EGFP) transfection. Secretion of IL-2 persisted for up to 3 weeks after electroporation. The increase in sensitivity against immunologic effector cells by transfection with IL-2 was not significant. Our results show the feasibility of a gene transfer into primary human melanoma cells, different from retroviral transduction.

Antigens, CD↗