Werner Hunstein

Epigallocatechin-3-gallate (EGCG) for Clinical Trials: More Pitfalls than Promises?

Epigallocatechin-3-gallate (EGCG), the main and most significant polyphenol in green tea, has shown numerous health promoting effects acting through different pathways, as antioxidant, anti-inflammatory and anti-atherogenic agent, showing gene expression activity, functioning through growth factor-mediated pathways, the mitogen-activated protein kinase-dependent pathway, the ubiquitin/proteasome degradation pathway, as well as eliciting an amyloid protein remodeling activity. However, epidemiological inferences are sometimes conflicting and in vitro and in vivo studies may seem discrepant. Current knowledge on how to enhance bioavailability could be the answer to some of these issues. Furthermore, dose levels, administration frequency and potential side effects remain to be examined.

Autologous blood stem-cell transplantation in patients with advanced Hodgkin's disease and prior radiation to the pelvic site.

Patients with relapsed Hodgkins disease who respond to salvage therapy are successfully treated with cyclophosphamide, carmustine (BCNU), and etoposide (VP-16) (CBV) followed by autologus bone marrow transplantation (ABMT). Because of heavy pretreatment including radiation to the pelvic site, marrow harvest was not feasible in those patients. We therefore used blood-derived hemopoietic precursor cells as an alternative stem-cell source to rescue them after superdose chemotherapy. Hemopoietic precursor cells were mobilized into the peripheral blood either by chemotherapeutic induction of transient myelosuppression followed by an overshooting of blood stem-cell concentration, or by continuous intravenous (IV) granulocyte-macrophage colony-stimulating factor (GM-CSF) administration. The median time to reach 1,000 WBC per microliter, 500 polymorphonuclear cells (PMN) per microliter, or 20,000 platelets per microliter was 10, 20.5, and 38 days, respectively, for 50% of all patients. The platelet counts of two patients never dropped below 20,000/microL following autologous blood stem-cell transplantation (ABSCT), whereas two other patients had to be supported with platelets for 75 and 86 days posttransplant until a stable peripheral platelet count of 20,000/microL was attained. Among the 11 assessable patients, seven are in unmaintained complete remission (CR) at a median follow-up of 318 days. This is a first report on a series of ABSCTs in patients with advanced Hodgkins disease proving that, despite prior damage to the marrow site, the circulating stem-cell pool is still a sufficient source of hemopoietic precursor cells for stem-cell rescue.

Sequential high-dose therapy with peripheral-blood progenitor-cell support in low-grade non-Hodgkin's lymphoma.

PURPOSE To evaluate the feasibility of a sequential high-dose therapy with peripheral-blood progenitor-cell (PBPC) support in patients with follicular lymphoma. PATIENTS AND METHODS Since July 1991, we have included 30 patients (17 men and 13 women) with a median age of 41 years (range, 26 to 55) in the study. At the time of study entry, 17 patients were in first and six in second or higher remission. Another six patients had relapse of disease and one had tumor progression. PBPC were collected during filgrastim-supported leukocyte recovery following high-dose cytarabine (ara-C)/mitoxantrone (HAM). RESULTS A median of two leukaphereses (range, one to seven) resulted in a median of 5.7 x 10(6) CD34+ cells/kg (range, 2.9 to 23.7 x 10(6). A distinct population of B-lymphoid progenitors (CD34+/CD19+) was not detectable in the autografts, and the content of CD19+ B cells was remarkably low, comprising a median of 0.07% of the mononuclear cells. Using the polymerase chain reaction (PCR) assay for the major breakpoint regions (MBR) of the bcl-2/immunoglobulin H (IgH) translocation, 22 patients had autografts positive for the t(14;18) translocation, whereas seven patients had PCR-negative transplants. The autograft of one patient could not be assessed. Following myeloablative therapy, hematologic recovery was rapid without cytokine support. The median times to reach a platelet count > or = 20 x 10(9)/L and neutrophil count > or = 0.5 x 10(9)/L were 11 and 13 days, respectively. Nonhematologic toxicity was moderate. Twenty-nine patients were alive in remission after a median follow-up duration of 6 months (range, 1 to 18). Of 22 patients autografted with t(14;18)-positive harvests, 11 had PCR-detectable cells in bone marrow and/or peripheral blood as long as 16 months posttransplantation. In contrast, six patients became PCR-negative between 3 and 16 months after reinfusion. Follow-up examinations with PCR data for the remaining five patients are not yet available. CONCLUSION Conversion to PCR negativity in patients autografted with PCR-positive harvests suggests that the myeloablative regimen is effective and that any reinfused t(14;18)-positive cells may not be sustained. Because conventional chemotherapy provides no cure, we believe that high-dose therapy including total-body irradiation (TBI) should be explored in these particularly radiosensitive lymphomas.

Characterization of blood mononuclear cells of rheumatoid arthritis patients: I. Depressed lymphocyte proliferation and enhanced prostanoid release from monocytes

Purified blood monocytes from patients with rheumatoid arthritis released enhanced amounts of the arachidonic acid products PGE, TXB2, and 6-keto-PGFα when compared to monocytes from healthy control individuals. The proliferative response of blood lymphocytes to concanavalin A was strongly suppressed in rheumatoid arthritis patients. Suppression of lymphocyte proliferation could not be reversed by in vitro addition of indomethacin, an inhibitor of prostaglandin synthesis. However, a restoration of lymphocyte proliferation was possible by reducing the high percentage of monocytes in the mononuclear cell fraction of rheumatoid arthritis patients (50 ± 6% versus 23 ± 5% in healthy controls). Although these findings indicate that monocytes of rheumatoid arthritis patients display a “stimulated” arachidonic acid metabolism, the depressed lymphocyte response appears to be due to the high number of monocytes and not to an enhanced PGE release.

Detection of residual tumor cells in patients with malignant melanoma responding to immunotherapy.

Summary: Recently, a highly sensitive assay combining reverse transcription and polymerase chain reaction (PCR) to assess for melanoma cells in peripheral blood has been developed. Detection of tyrosinase mRNA, a tissuespecific enzyme in melanocytes and melanoma cells, indicates the presence of melanoma cells in peripheral blood. We examined blood samples and bone marrow aspirates from 28 patients with metastatic malignant melanoma for presence of melanoma cells prior to and after therapy with interferon (IFN)-α and interleukin (IL)-2. ten patients showed antitumor response to immunotherapy, including three complete (CR) and seven partial remissions (PR). Four patients (three PR, one stable disease) underwent subsequent resenction of resicdual tumor lesions and had no clinical evedence fo disease after surgery. Tyrosinaswe mRNA was detected in blood and bone marrow samples from all patients with malignant melanoma prior to and after immunotherapy, including those with no clinical evidence of disease (median disease–free survival 21 months, range 19–28 months). Tyrosinase transcripts were also detected in all patients with amelanotic melanoma. In contrast, no tyrosinase mRNA was detectable in any of 30 healthy persons or in six patients with other malignancies. The presence of residualj melanoma cells may be an important indicator of occurrence of delayed relapse.

Prevention of catheter-related infections by silver coated central venous catheters in oncological patients

Catheter-related infection (CRI) is a serious complication of central venous catheterization. We have investigated the efficacy of a silver-coated polyurethane catheter (Pellethane, Fresenius AG, Germany) in preventing CRI in oncological patients receiving chemotherapy in a phase II study. From November 1992 through April 1994, 266 patients were assigned to receive single lumen catheters, either standard uncoated catheters (UC, n = 113) or silver-coated ones (SC, n = 120). Catheters were inserted into the internal jugular vein after institutional approval and informed consent. Duration of catheterization (UC vs. SC = 13.3 vs. 12.7 days) and leukopenia (< 1.0 x 10(9) WBC/l; 4.3 vs. 3.6 days) were similar in both groups demonstrating a comparable risk for infections. Skin reactions at the catheter entry site were recorded daily. CRI and colonization rates were studied by semiquantitatively culturing intradermal and intravascular segments. CRI were confirmed by blood cultures obtained via catheter and from peripheral veins in cases of suspected sepsis or at the end of catheterization. No adverse effects from the silver-coated catheter could be observed. The bacteriological results showed that SC were colonized (> 15 CFU) in 45.1% and UC in 44.2%. CRI developed in 21.2% of the UC patients but only in 10.2% of the SC patients (p = 0.011). We conclude that this new silver-coated central venous catheter is biocompatible and effective in reducing the incidence of catheter-related infections in oncological patients.

Evaluation of soluble tumor necrosis factor (TNF) receptors and TNF receptor antibodies in patients with systemic lupus erythematodes, progressive systemic sclerosis, and mixed connective tissue disease

Two TNF binding proteins have been characterized as soluble fragments of TNF receptors. We measured the plasma concentrations of soluble type A (p75) and type B (p55) TNF receptors in patients with systemic lupus erythematodes (SLE), progressive systemic sclerosis (PSS), and mixed connective tissue disease (MCTD). In SLE and PSS patients plasma concentrations of both types of TNF receptors and in MCTD patients type A TNF receptors were significantly elevated compared to controls. Plasma concentrations of both soluble TNF receptors were highly correlated in SLE, PSS, and MCTD patients, indicating a possible coregulation of both TNF receptors. In contrast, soluble interleukin 2 receptor (sCD 25) plasma concentrations were not correlated and seem to be an independent parameter. The soluble forms of the TNF receptors neutralize TNF in cytotoxicity assays and are functionally active as TNF antagonists. In one patient with SLE, autoantibodies against type A TNF receptors were detected, TNFα, and TNFβ did not interfere with the autoantibody binding to the receptor.

Elevated TNF receptor plasma concentrations in patients with rheumatoid arthritis.

SummaryTwo types of tumor necrosis factor receptors have been characterized, both capable of transmitting the signal and exerting the biological functions of TNF and lymphotoxin. We measured the plasma concentrations of two types of TNF binding proteins (sTNFR-A and sTNFR-B) in patients with rheumatoid arthritis (RA) and spondylarthropathies (SpA) using an enzyme-linked binding assay. In normal controls (n = 43), mean plasma concentrations were 1030 ± 55 and 1461 ±59 pg/ml for sTNFR types A and B, respectively. In 67 patients with moderate RA, mean levels were 1422 ± 82 pg/ml (type A) and 2088 ± 109 pg/ml (type B); in 34 patients with severe RA, 2588 ±279 pg/ml and 4494 ± 550 pg/ml, respectively, were measured (P < 0.0001 compared to normal controls). Concentrations of both type A and type B sTNFR were highly correlated in severe RA (R2 = 0.7) but not in SpA or normal controls. T lymphocytes in synovial fluid of patients with RA expressed predominantly type A TNF receptors on their surface; in some patients a weaker expression of type B receptors was also detectable. Soluble TNF binding proteins in patients with RA were able to neutralize TNF in a cytotoxiity assay, demonstrating their ability to act as “TNF-inhibiting factors”. We conclude that both types of TNF receptors are parameters of disease activity in RA and may also act as TNF antagonists.

Phase-I trial of intravenous continuous infusion of tumor necrosis factor in advanced metastatic carcinomas

SummaryFifteen patients with advanced metastatic adenocarcinomas were treated in a phase-I study with continuous intravenous 24h infusion of recombinant tumor necrosis factor α (TNF-α) in order to determine the maximum tolerated dose (MTD) and associated side-effects. Patients received 40–400 μg/m2 TNF-α once (arm A) or twice (arm B) weekly for a scheduled treatment period of 2 months. The observed systemic side-effects resembled those reported for interferons and included fever, chills, fatigue, headaches, myalgias, thrombocytopenia, prostration, and malaise. Dose-limiting toxicities, resulting in a median MTD of 200 μg/m2 for 24h, were fever, chills, fatique, myalgias, and thrombocytopenia. Out of 15 patients, 11 showed tumor progression, and 3 sustained in no change for over 2 months of treatment. A minor response was seen in 1 patient with a colorectal carcinoma and liver metastases. To reduce side-effects, patients were treated either with paracetamol or indomethacin. Higher MTDs were observed in patients treated with indomethacin. No detectable plasma TNF-α levels or TNF antibodies were measured under therapy (plasma TNF-α<20 pg/ml). We conclude that TNF-α appears to have some antineoplastic activity in patients with adenocarcinomas since 4 patients remained in no change or showed a minor response.

Cataract incidence after total-body irradiation

PURPOSE The aim of this retrospective study was to evaluate cataract incidence in a homogeneously-treated group of patients after total-body irradiation (TBI) followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. METHODS AND MATERIALS Between 1982 and 1994, a total of 260 patients received either autologous bone marrow or blood stem cell transplantation for hematological malignancy at the University of Heidelberg. Two hundred nine of these patients received TBI in our hospital. Radiotherapy was applied as hyperfractionated TBI, with a median dose of 14.4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 h. Photons with an energy of 23 MeV were used with a dose rate of 7-18 cGy/min. Ninety-six of the 209 irradiated patients were still alive in 1996; 86 of these patients (52 men, 33 women) answered a questionnaire and could be examined ophthalmologically. The median age at time of TBI was 38.5 years, with a range of 15-59 years. RESULTS The median follow-up is now 5.8 years, with a range of 1.7-13 years. Cataract occurred in 28/85 patients (32.9%) after a median of 47 months (1-104 months). In 6 of 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to TBI had been performed more often in the group of patients developing cataract (14.3%) versus 10.7% in the group of patients without cataract. However, there was no statistical difference (Chi-square, p>0.05). CONCLUSION Cataract is a common side effect of TBI. Cataract incidence found in our patients is comparable to results of other centers using a fractionated regimen for TBI. To assess the incidence of cataract after TBI, a long-term follow-up is required.