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K Höffken

Publications and source records attributed to K Höffken.

At least 55 records · Page 3Linked to original sources
PubMed2000

Bone morphogenetic protein 2 (BMP-2) induces sequential changes of Id gene expression in the breast cancer cell line MCF-7.

Bone morphogenetic proteins (BMPs) are involved in the development of various organs including the mammary gland. They are well-regulated and act in a time-, concentration- and cell-type-specific manner. We found that BMP-2 is expressed in primary breast tumor tissue samples and in breast cancer cell lines. Hybridization of labeled cDNA, obtained from the breast cancer cell line MCF-7, against the Atlas human cDNA expression array revealed differential gene expression depending on BMP-2 treatment. The most prominent changes were observed for the helix-loop-helix proteins Id-1, Id-2 and Id-3. Id-1 expression had increased severalfold after 4 h and was even higher after 24 h. Id-2 and Id-3 were more strongly induced after 4 h and showed no further significant change after 24 h. Analysis of cell-cycle distribution revealed a marked increase of the sub-G1 phase after 48 h in serum-deprived cells. In the presence of BMP-2 no change was observed over 48 h indicating that BMP-2 does not induce apoptosis. In addition, expression of caspase-3 was reduced in BMP-2-treated cells after 24 h. In summary, our results clearly indicate that BMP-2 is a susceptibility factor keeping the cells ready for the integration of various other signals for cell progression.

Bone Morphogenetic Protein 2↗
PubMed2000

[Geriatric oncology].

The demographic development will result in a major increase in the number of elderly cancer patients. Age is the main risk factor for the development of a malignant disease. The incidence of the main cancer diagnosis increases with advancing age. Treatment of elderly cancer patients is an exquisite task. On the one hand, an increased morbidity and mortality may be the result of an unreflected transfer into the geriatric setting of treatment schedules developed for younger patients. On the other hand, reduction of dose intensity can result in decreased survival, life prolongation or insufficient palliation. Elderly people are a very heterogeneous group. Some are in a very good health status. Others are impaired, dependent, suffer from a number of comorbidities and have to take a variety of drugs. Those conditions and not the chronological age influence tolerance against tumour therapy. For elderly patients maintenance of independence and quality of life is more important than disease free survival and prolongation of life.

Aged↗
PubMed1999

Expression, regulation and clinical significance of bone morphogenetic protein 6 in esophageal squamous-cell carcinoma.

Bone morphogenetic proteins (BMPs) are multifunctional cytokines. BMP-6 is involved in early steps of keratinogenesis. Esophageal squamous-cell carcinoma often shows abnormal keratinization. The aim of this study was to examine the expression and regulation of BMP-6 in esophageal carcinoma and to determine the relationship of its expression with tumor characteristics and survival. Avidin-biotin-peroxidase staining was performed using paraffin-wax-embedded tumor specimens collected from 172 patients with esophageal squamous-cell carcinoma, who underwent potentially curative surgery. Expression of BMP-6 and EGF-receptor in the esophageal-squamous-cell-carcinoma cell line COLO-680N and the hypopharyngeal-squamous-cell-carcinoma cell line FaDu was assayed with specific RT-PCR. In standard cell-cultivation conditions, COLO-680N and FaDu cells showed distinct expression of BMP-6, whereas in serum-free conditions BMP-6 expression was hardly detectable. The addition of EGF or EGF-related growth factors could elevate BMP-6 mRNA content. Immunohistochemically, all 172 tumors exhibited cytoplasmic immunoreactivity for BMP-6. The content of BMP-6 protein was inversely correlated with tumor differentiation (p < 0.01). Univariate survival analysis revealed that 74 patients with tumors of low immunoreactivity had higher 2-year and 5-year survival rates (50.0%/27.7%) than 75 patients with tumors of high immunoreactive scores (33.3%/21.6%). (p < 0.05). We conclude that BMP-6 is expressed in esophageal squamous-cell carcinoma. EGF-receptor activation is crucial for regulation of BMP-6 expression. BMP-6 protein content is correlated with the grade of tumor-cell differentiation and may add to indications of poor prognosis.

Adult↗
PubMed1999

Expression of bone morphogenetic protein 6 in normal mammary tissue and breast cancer cell lines and its regulation by epidermal growth factor.

Bone morphogenetic proteins (BMPs) are multifunctional regulators of proliferation, differentiation and apoptosis. BMP-6 is involved in numerous developmental processes. We have demonstrated expression of BMP-6 in breast cancer cell lines by RT-PCR and immuno-histochemistry. The level of BMP-6 mRNA decreased upon serum starvation, whereas epidermal growth factor (EGF) treatment led to elevation of BMP-6 mRNA levels in a dose-dependent manner, with a maximum at 50 ng/ml EGF under serum-free conditions in hormone-sensitive (MCF-7) and in hormone-insensitive (SK-BR-3) breast cancer cell lines. The EGF-like growth factors transforming growth factor-alpha, amphiregulin and betacellulin were also able to elevate the BMP-6 mRNA level after 24 hr. Inhibition of EGF receptor tyrosine kinase with tyrphostine AG 1517 repressed the inductive effect of these growth factors, indicating an EGF receptor-mediated regulation of BMP-6 mRNA. In addition, BMP-6 mRNA was detected in tumor samples from breast carcinoma patients. However, levels were reduced in 18/44 samples compared with tumor-free resection margins. In 12 of these 18 patients, at least a 10-fold reduction of EGF receptor mRNA levels in tumor samples vs. tumor-free samples was observed. This suggests a putative relationship between EGF receptor and BMP-6 mRNA levels in breast cancer.

Bone Morphogenetic Protein 6↗
PubMed1999

Treatment of patients with low-risk myelodysplastic syndromes using a combination of all-trans retinoic acid, interferon alpha, and granulocyte colony-stimulating factor.

Used as single agents, ATRA, G-CSF, and IFN-alpha have shown a moderate benefit in patients with low-risk MDS, with a response rate of 10%. The aim of the present study was to evaluate the efficacy of a combination of these agents. The effect on hemoglobin (Hb), platelets, and absolute neutrophil count (ANC), as well as on transfusion frequency, was examined in 25 patients with MDS (11 RA, four RARS, eight RAEB, two CMML). The median age was 61 years (range 44-81), and the male/female ratio was 14/11. Treatment consisted of ATRA at 25 mg/m2/day p.o. for months 1, 3, 5, 7, 9, and 11, IFN-alpha at 1.5 MIU twice a week s.c. for 52 weeks, and, in patients with initial ANC <500/microl, G-CSF at 100-480 microg daily s.c. according to the degree of ANC. The duration of therapy was scheduled for 12 months. Two patients achieved ongoing CR (+19 months; +16 months), one patient with RA after 3 months and one with CMML after 7 months of treatment. In all patients, the mean ANC increased significantly from 1400+/-200/microl before the start of therapy to 3500+/-600/microl at the end of treatment (p=0.025). In two patients an increase of Hb was observed, and one patient ceased to require transfusions. In an additional patient with RA and 5q-syndrome, the platelet count normalized following administration of ATRA/IFN-alpha, increasing from 89,000/microl to 293,000/microl. The eight RAEB patients were nonresponders. We conclude that therapy with ATRA, IFNalpha, and G-CSF is effective in approximately 35% of low-risk MDS patients (in this study: six of 17) and may induce complete remission in individual cases.

Adult↗
PubMed1999

The role of apoptosis in hematologic malignancies and modulation of apoptosis as a new therapeutic approach.

Recently, the role of apoptosis in the pathogenesis of a wide array of diseases (e.g. solid tumors, leukemias, myelodysplastic syndromes and aplastic anemia) has been highlighted. Thus modulation of this pivotal process (either positively or negatively) has become an emerging new concept in the treatment of malignant disorders. In this review we will discuss recent advances in the understanding of apoptosis, outline its role in the pathophysiology of several hematologic disorders and suggest possible novel treatment strategies.

Apoptosis↗
PubMed1999

Severe non-haematological toxicity after treatment with gemcitabine.

The authors report that 4 out of a series of 56 patients (7.1%) treated with gemcitabine developed an unexplained non-cardiogenic pulmonary distress syndrome most likely related to gemcitabine. One further patient developed ventricular arrhythmia immediately after gemcitabine exposure, leading to cardiac arrest. Between 1995 and 1998 56 patients with locally advanced or metastatic carcinoma were treated with gemcitabine. The patients suffered from breast cancer (n = 17), pancreatic cancer (n = 17), lung cancer (n = 12), cancer of unknown primary (n = 5), ovarian cancer (n = 2), oral cavity cancer (n = 2) and cancer of the bladder (n = 1). Their median age was 55 years, and there were 33 female and 23 male patients. Fifteen patients had been pretreated with radiation therapy: 2 had received radiation therapy involving the mediastinum as treatment for non-small-cell lung cancer and cancer of unknown origin respectively, 11 patients had had prior neoadjuvant or adjuvant radiation therapy of the chest wall for breast cancer and 2 patients had received radiation therapy for head/neck cancer. All patients received gemcitabine on days 1, 8 and 15 and this was repeated on day 29 at a dose of 1000 mg/m(2) as a 30-min infusion in 250 ml isotonic NaCl. In 4 patients gemcitabine treatment was combined with cisplatinum, in 7 patients with a somatostatin analogue and in 1 patient with epirubicin. All other patients received gemcitabine as a single agent. We assume that the pulmonary or cardiac toxicity of 5 patients was related to gemcitabine. In 3 patients re-exposure resulted in repeated toxicity. One patient did not receive gemcitabine again because of the life-threatening nature of the primary response. Two patients had received prior radiation to the mediastinum with 62 Gy and 50 Gy respectively, 3 years and 1 year before gemcitabine application. In our experience pulmonary toxicity after gemcitabine treatment is more common than initially anticipated. Gemcitabine should be used with caution in patients who have received prior radiation to the mediastinum.

Adult↗
PubMed1998

Impaired granulocytic function in patients with acute leukaemia: only partial normalisation after successful remission-inducing treatment.

In vivo chemotaxis and phagocytic activity of polymorphonuclear neutrophils (PMN) were evaluated in 20 patients with acute myeloid leukaemia (AML), and in 10 patients with acute lymphoblastic leukaemia (ALL). For comparison, 20 healthy individuals were investigated. A skin-chamber technique and a phagocytosis test were used to quantify the neutrophil functions. The local leucocyte mobilisation in the skin-chamber was significantly lower in untreated patients with AML and ALL than in healthy individuals (P < 0.05). Patients with acute leukaemia in remission showed an increase in chemotactic parameters though they remained below normal levels. The phagocytosis index (PI) of peripheral blood PMN was lower than 30% (normal individuals: 60%) in untreated AML and ALL; this difference was significant (P < 0.05). The PI of peripheral blood PMN in patients with acute leukaemia in remission returned to the normal level. Investigation of granulocytic function in patients with acute leukaemia in remission may reveal evidence for reduced protection by these cells against infections and lead to adequate therapy.

Adolescent↗
PubMed1998

Pharmacoeconomic evaluation of high-dose chemotherapy and peripheral blood stem cell support in high-risk or poor-prognosis malignancies.

Discussion of the total costs and cost-effectiveness ratios of patients receiving high-dose chemotherapy (HDC) and peripheral blood stem cell support (PBSCS) is controversial. In Germany, no reliable data are available, whereas in other countries this issue has been extensively studied. We performed a pharmacoeconomic evaluation on all patients (n = 37) treated with HDC and PBSCS at our institution between July 1994 and June 1997. Patients suffered from high-risk or poor-prognosis breast cancer (n = 24), Hodgkin's disease (n = 3), high-grade non-Hodgkin's lymphoma (n = 4), multiple myeloma (n = 2), small-cell cervical cancer (n = 1), malignant hystiocytosis (n = 1) and testicular cancer (n = 2). For pharmacoeconomic evaluation, the period from initiation of induction chemotherapy (IC) until reconstitution after the last course of HDC and PBSCS was considered. A total of 18 patients received IC/HDC/PBSCS for locally advanced or systemic disease, and 19 patients received adjuvant or consolidation IC/HDC/PBSCS. Treatment protocols were heterogeneous. Patients were treated with two to five courses (median two) respectively of IC and sequential mono-HDC (n = 26), tandem-HDC (n = 10) or triple-HDC (n = 1). All patients received granulocyte/macrophage-colony-stimulating factor (G-CSF) for stem cell mobilisation and for amelioration of neutropenia after HDC. The relative costs (based on supplier prices) for the total amount of drugs prescribed during the in-patient period was 29.8% for G-CSF, 35.8% for blood products 18.5% for chemotherapy, 2.4% for antiemetics, 5.9% for antimicrobial drugs and 7.6% for other drugs. Contrary to expectations, antimicrobial drugs had only a minor pharmacoeconomic impact during IC/HDC/PBSCS in patients with high-risk or poor-prognosis malignancies, indicating that prolonged septic complications were uncommon in our institution. We conclude that pharmacoeconomic evaluations in IC/ HDC/PBSCS might be integrated into the effort to ensure quality control and monitoring.

Antineoplastic Agents↗
PubMed1998

A phase II study of weekly high-dose 5-fluorouracil and leucovorin plus biweekly alternating doxorubicin and cisplatin for advanced gastric carcinoma.

On the basis of recent clinical data suggesting that high-dose continuous 5-fluorouracil (5-FU) is able to overcome resistance to 5-FU bolus application in gastric carcinoma, a phase II study was performed to evaluate the activity and toxicity of weekly high-dose 5-FU and leucovorin plus biweekly alternating doxorubicin and cisplatin as the first-line treatment in patients with advanced gastric carcinoma. Between October 1995 and September 1997, 24 consecutive patients with locally advanced (n=4) or metastatic (n=20) gastric carcinomas were treated with a combination of 500 mg/m2 leucovorin as a 2-h infusion, followed by 2.0 g/m2 5-FU as a 24-h continuous infusion once weekly for 6 weeks, plus 20 mg/m2 doxorubicin as a bolus application and 50 mg/m2 cisplatin as a 1-h infusion, week 1, 3 and 5 (FLAP regimen). Response, toxicity and survival data were evaluated. A total of 20 patients were evaluable for response and 24 for toxicity. Objective responses were observed in 11 patients (55%) with no complete remission. Four patients (20%) showed stabilization and 5 patients (25%) experienced progressive disease. The median time to disease progression was 8 months and the overall duration of survival was 14 months. Myelosuppression was significant. In 2 patients, grade 4 WHO thrombocytopenia and leukopenia/anaemia respectively were registered, but there were no treatment-related deaths. We conclude that the weekly alternating FLAP regimen is effective in advanced gastric carcinoma with tolerable toxicity. However, significant myelotoxicity and frequent hospitalization suggest that FLAP should not be preferred to other regimens used in metastatic disease. Currently we intend to establish this regimen in the neoadjuvant setting in patients with primary unresectable localized gastric carcinomas.

Adult↗
PubMed1998

Correlation between granulocyte/macrophage-colony-forming units and CD34+ cells in apheresis products from patients treated with different chemotherapy regimens and granulocyte-colony-stimulating factor to mobilize peripheral blood progenitor cells.

We examined the efficiency of disease-specific "standard" chemotherapies epirubicin, cyclophosphamide (EC); cyclophosphamide, vincristine, doxorubicin, etoposide, prednisolone (CHOEP); epirubicin, ifosfamide (EPI/IFOS) for peripheral blood progenitor cell (PBPC) mobilization in comparison to well-characterized mobilization protocols, i.e. etoposide, ifosfamide, cisplatin, epirubicin (VIPE) and dexamethasone, carmustine, etoposide, cytarabine, melphalan (DexaBEAM). Twenty-seven patients with various malignancies underwent 75 apheresis procedures for PBPC collection. Median cell yields from all 75 aphereses were 1.18 x 10(5) mononuclear cells/kg [range (0.28-3.7) x 10)8)], 1.4 x 10(5) granulocyte/macrophage-colony-forming units (CFU-GM)/kg [range (0.2-11) x 10(5)] and 3.3 x 10(6) CD34+cells/kg [range (0.35-17.7) x 10(6). CD34+/ CD90+ cells could be mobilized by all mobilization regimens used. The difference observed in the mobilization of CD34+ cells was only of low significance when the mobilization regimens were compared, whereas the mobilizations of MNC and CFU-GM were significantly different between the groups. Breast cancer patients treated with the VIPE regimen (including pretreated women) had a significantly higher CFU-GM rate than patients treated with EC (P=0.0005). Mobilized CD34+ PBPC were correlated with CFU-GM in all apheresis products. The linear correlation coefficients differed for the various mobilization groups: DexaBEAM (r=0.9, P < 0.0001), VIPE (r=0.68, P=0.0024), CHOEP (r=0.52, P=0.022), EPI/ IFOS (r=0.34, P=0.11) and EC (r=0.23, P=0.2). We conclude that clonogenic assays can provide additional information about the autotransplant quality, particularly when alternative or new mobilization regimens are being investigated.

Antigens, CD34↗
PubMed1998

Bendamustine as salvage treatment in patients with advanced progressive breast cancer: a phase II study.

A phase II pilot study of bendamustine as salvage treatment in patients with advanced breast cancer was performed to determine the objective response rates and make further observations on the toxicity of this drug. A group of 37 patients, pretreated with chemotherapy for advanced disease, entered the trial. Treatment consisted of 150 mg/m2 bendamustine on days 1 and 2 of a 4-week treatment course. Patients continued to receive treatment until complete remission and then two further courses, until tumour progression or unacceptable toxicity ensued. A total of 36 patients received at least one treatment course and were assessable for toxicity; 33 patients were evaluable for treatment results. Dose-limiting grade 3 and 4 WHO toxicity occurred in 5 and 3 patients respectively; 27% of patients entered complete or partial tumour remission. The median time to tumour progression was 2 months with a range of 1-14 months. The efficacy of bendamustine was apparently independent of pretreatment with anthracyclines, suggesting a lack of cross-resistance between bendamustine and anthracyclines. It can be concluded that bendamustine in the dose and application schedule used here is active in the salvage therapy of women with advanced breast cancer. The toxicity was acceptable. Future studies have to confirm the data of this pilot trial and to define the role of bendamustine in the combination chemotherapy of metastatic breast cancer that has been suggested by previous trials.

Adult↗
PubMed1998

Monoclonal antibody therapy for resected Dukes' C colorectal cancer: seven-year outcome of a multicenter randomized trial.

PURPOSE: As previously shown, antibody treatment increased survival of patients with resected colorectal cancer of stage Dukes' C. Since the 5-year analysis was criticized because of the wide range (2.7 to 7.5 years) of follow-up time, we performed a 7-year analysis with only four of 189 patients monitored for less than 5 years. PATIENTS AND METHODS: A total of 189 patients with resected Dukes' C colorectal cancer were randomly allocated to infusions of a total of 900 mg 17-1A antibody, 500 mg postoperatively followed by 4 monthly doses of 100 mg (n=99), or to observation only (n=90). Primary end points were overall survival and disease-free interval. Patients were stratified by a dynamic randomization according to center, sex, location of tumor, number of affected lymph nodes, and preoperative carcinoembryonic antigen concentration. RESULTS: Randomization produced balanced distribution of risk factors. After 7 years of follow-up evaluation, treatment had reduced overall mortality by 32% (Cox's proportional hazard, P < .01; log-rank, P=.01) and decreased the recurrence rate by 23% (Cox's proportional hazard, P < .04; log-rank, P=.07). The intention-to-treat analysis gave a significant effect for overall survival (Cox's proportional hazard, P < .01; log-rank, P=.02) and disease-free survival (Cox's proportional hazard, P=.02; log-rank, P=.11 ). While distant metastases were significantly reduced (Cox's proportional hazard, P=.004; log-rank, P=.004), local relapses were not (Cox's proportional hazard, P=.65; log-rank, P=.52). This differential effect of 17-1A antibody on disseminated isolated tumor cells versus occult local satellites may explain the increased significance seen in the overall survival. CONCLUSION: The now-matured study shows that 17-1A antibody administered after surgery prevents the development of distant metastasis in approximately one third of patients. The therapeutic effect is maintained after 7 years of follow-up evaluation.

Adenocarcinoma↗
PubMed1997

[High dose chemotherapy of solid tumors].

BACKGROUND: The availability of hemopoetic growth factors and the retransfusion of autologous peripheral blood stem cells (PBSC) have enabled high-dose chemotherapy (HDT) options for the treatment of advanced solid tumours, during recent years. Though the transfusion of PBSC can manage the myelosuppression, dose-escalation ist still limited by non-haematological toxicity. METHOD: Usually, HDT has been given after a proceeding dose-intense chemotherapy that allowed the evaluation of chemosensitivity of the disease and resulted in a stem cell mobilization into the peripheral blood. The autologous bone marrow transplantation has almost completely been replaced by retransfusion of PBSC together with hemopoietic growth factors as specific supportive treatment. The PBSC are harvested by apheresis using a blood cell separator. RESULTS: Results on the efficacy of HDT are available for breast, testicular, ovarian, small cell lung cancer as well as melanoma, glioblastoma and soft-tissue sarcoma. The studies showed the feasibility and efficacy of HDT with tolerable toxicity. CONCLUSION: High-dose chemotherapy will be of increasing importance in the treatment strategies of primary solid tumors, in the near future.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

BRCA1 mutations and phenotype.

More than 100 mutations have been described for the breast-cancer-susceptibility gene BRCA1. The paper describes phenotypical aspects of three selected mutations located at the beginning, in the middle, and at the end of the gene. A remarkable decrease of the age of diagnosis of the mammary carcinoma is observed with increasing length of the putative gene product, combined with greater severity of the disease.

Adult↗