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1.
Ann Oncol ; 13(8): 1225-35, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12181246

ABSTRACT

BACKGROUND: Docetaxel has yielded promising response rates as a component of doxorubicin-based combination schedules in patients with metastatic breast cancer, including docetaxel/doxorubicin and docetaxel/doxorubicin/cyclophosphamide (AC). This randomized two-stage phase II study was conducted to evaluate sequential treatment with docetaxel and AC as first-line treatment in patients with recurrent or metastatic breast cancer previously untreated with chemotherapy for metastatic disease. PATIENTS AND METHODS: Thirty-three patients were randomized to either docetaxel (100 mg/m(2)) on day 1 of a 21-day cycle for three cycles followed by AC (60/600 mg/m(2)) on day 1 of a 21-day cycle for three cycles (n = 17) or vice-versa (n = 16), without prophylactic granulocyte colony-stimulating factor support. In addition, we compared pre-treatment serum sErbB1 and sErbB2 protein concentrations with that of an age- and menopausal status-matched group of healthy women, and examined changes in serum sErbB1 and sErbB2 protein concentrations in these two treatment schedules. Data from each one of the two arms of the trial (docetaxel then AC, or AC and then docetaxel) were analyzed separately. RESULTS: Enrollment was suspended after the first-stage of accrual, based on statistical design. Confirmed objective response rates after six cycles of treatment were 35% [95% confidence interval (CI) 14% to 62%] with docetaxel then AC and 38% (95% CI 15% to 65%) with AC then docetaxel. Dose reductions were frequent and mostly due to grade 4 neutropenia. Median survival time was 2.5 years in the docetaxel then AC group, and 1.1 years in the AC then docetaxel group. Serum sErbB1 concentrations were not significantly different between the study patients and healthy women, and did not change significantly after three and six cycles of treatment. In contrast, serum sErbB2 concentrations were significantly higher in the study patients compared with healthy women and tended to decrease after three and six cycles of treatment. CONCLUSIONS: Response rates at the end of six cycles of treatment, which led to termination of accrual after the first stage using either the sequence of docetaxel first or docetaxel after AC chemotherapy, were lower than anticipated. However, median survival times and median progression-free survival times are similar to those reported in other studies. These data further suggest that additional studies to assess whether serum sErbB2 concentrations are useful predictors of responsiveness to chemotherapy are warranted.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Breast Neoplasms/drug therapy , Neoplasm Recurrence, Local/drug therapy , Paclitaxel/analogs & derivatives , Taxoids , Adenocarcinoma/drug therapy , Adenocarcinoma/pathology , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/drug therapy , Carcinoma, Ductal, Breast/pathology , Carcinoma, Lobular/drug therapy , Carcinoma, Lobular/pathology , Case-Control Studies , Cyclophosphamide/administration & dosage , Disease Progression , Docetaxel , Doxorubicin/administration & dosage , ErbB Receptors/blood , Female , Humans , Middle Aged , Neoplasm Recurrence, Local/pathology , Paclitaxel/administration & dosage , Receptor, ErbB-2/blood , Remission Induction , Survival Rate
2.
Cancer ; 92(2): 420-33, 2001 Jul 15.
Article in English | MEDLINE | ID: mdl-11466698

ABSTRACT

BACKGROUND: The current study was conducted to determine whether the addition of interferon-alpha (IFN-alpha) to treatment with radiation therapy and carmustine (BCNU) improves time to disease progression or overall survival in patients with high-grade glioma. METHODS: Patients with anaplastic astrocytoma, anaplastic oligoastrocytoma, glioblastoma multiforme, or gliosarcoma received radiation therapy plus BCNU as initial therapy. Subsequently, patients without tumor progression at the completion of radiation therapy were stratified by age, extent of surgery, tumor grade and histology, Eastern Cooperative Oncology Group performance status, and treating institution, and then were randomly assigned to receive either BCNU alone (200 mg/m(2) on Day 1) or BCNU (150 mg/m(2) on Day 3) plus IFN--alpha (12 million U/m(2) on Days 1-3, Weeks 1, 3, and 5) every 7 weeks for a maximum of 6 cycles. RESULTS: Of the 383 patients enrolled in the study, 275 eligible patients were randomized. There was no significant difference with regard to time to disease progression or overall survival between the two groups. Patients receiving IFN-alpha experienced more fever, chills, myalgias, and neurocortical symptoms including somnolence, confusion, and exacerbation of neurologic deficits. Cox multivariate regression models confirmed known favorable prognostic variables including younger age, Grade 3 tumor (according to World Health Organization criteria), and greater extent of surgery. Cox and classification and regression tree analysis models also demonstrated that a normal baseline Folstein mini-mental status examination (MMSE) score was associated with better prognosis. CONCLUSIONS: IFN-alpha does not appear to improve time to disease progression or overall survival in patients with high-grade glioma and appears to add significantly to toxicity. The baseline MMSE score may serve as an independent prognostic factor and warrants further investigation.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Antineoplastic Agents/pharmacology , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Brain Neoplasms/drug therapy , Brain Neoplasms/radiotherapy , Carmustine/pharmacology , Glioma/drug therapy , Glioma/radiotherapy , Interferon-alpha/pharmacology , Adult , Aged , Antineoplastic Agents/administration & dosage , Antineoplastic Agents, Alkylating/administration & dosage , Brain Neoplasms/pathology , Carmustine/administration & dosage , Combined Modality Therapy , Disease Progression , Female , Glioma/pathology , Humans , Interferon-alpha/administration & dosage , Male , Middle Aged , Neoplasm Staging , Survival Analysis , Treatment Outcome
3.
Cancer ; 91(7): 1191-200, 2001 Apr 01.
Article in English | MEDLINE | ID: mdl-11283917

ABSTRACT

BACKGROUND: This study evaluated the dose-response relation for zoledronic acid, a new generation high potency bisphosphonate, given as a 5-minute infusion in patients with malignant osteolytic disease. METHODS: Two-hundred eighty patients with osteolytic lesions due to metastatic breast carcinoma or multiple myeloma were randomized to double-blind treatment with either 0.4, 2.0, or 4.0 mg of zoledronic acid or 90 mg pamidronate. The primary efficacy endpoint was the proportion of patients receiving radiation to bone. Other skeletal-related events, bone mineral density (BMD), bone markers, Eastern Cooperative Oncology Group performance status, pain and analgesic scores, and safety also were evaluated. RESULTS: Zoledronic acid at doses of 2.0 and 4.0 mg and pamidronate at a dose of 90 mg each significantly reduced the need for radiation therapy to bone (P < 0.05) in contrast with 0.4 mg zoledronic acid, which did not. Skeletal-related events of any kind, pathologic fractures, and hypercalcemia also occurred less frequently in patients treated with 2.0 or 4.0 mg zoledronic acid or pamidronate than with 0.4 mg zoledronic acid. Increases in lumbar spine BMD (6.2-9.6%) and decreases in the bone resorption marker N-telopeptide (range, -37.1 to -60.8%) were observed for all treatment groups. Skeletal pain, fatigue, nausea, vomiting, and headache were the most commonly reported adverse events. Adverse events were similar in nature and frequency with zoledronic acid and pamidronate. CONCLUSIONS: A 5-minute infusion of 2.0-4.0 mg zoledronic acid was at least as effective as a 2-hour 90-mg pamidronate infusion in treatment of osteolytic metastases. A 0.4-mg dose of zoledronic acid was significantly less effective. Both zoledronic acid and pamidronate were well tolerated.


Subject(s)
Bone Neoplasms/drug therapy , Bone Neoplasms/secondary , Diphosphonates/administration & dosage , Imidazoles/administration & dosage , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Biomarkers, Tumor/urine , Bone Density/drug effects , Bone Neoplasms/complications , Bone Neoplasms/radiotherapy , Bone Resorption , Breast Neoplasms/pathology , Collagen/urine , Collagen Type I , Creatinine/urine , Diphosphonates/adverse effects , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Imidazoles/adverse effects , Infusions, Intravenous , Male , Middle Aged , Multiple Myeloma/pathology , Pain Measurement , Pamidronate , Peptides/urine , Zoledronic Acid
4.
Clin Cancer Res ; 6(9): 3486-92, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10999733

ABSTRACT

There continues to be a need for new systemic approaches for the treatment of advanced pancreatic cancer. The purpose of this study was to compare the antitumor activity of the somatostatin analogue octreotide to 5-fluorouracil chemotherapy in a Phase III setting. Eighty-four patients with an Eastern Cooperative Oncology Group performance status of 0 or 1 and limited tumor volume were randomized to receive octreotide 200 microg three times daily or 5-fluorouracil with or without leucovorin. After the first 12 patients had been randomized to octreotide, we increased the dose in the remaining patients to 500 microg three times daily. This change was based on early reports in other studies, suggesting that our original dose may not have been effective and that higher doses of octreotide were well tolerated. A planned interim analysis performed after 84 patients were enrolled demonstrated inferior time to progression and survival for the patients randomized to octreotide. Further accrual to the octreotide arm of this protocol was therefore terminated. Octreotide in doses of 200-500 microg three times daily does not delay progression or extend survival in patients with advanced pancreatic cancer compared with treatment with 5-fluorouracil with or without leucovorin.


Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Antineoplastic Agents, Hormonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Pancreatic Ductal/drug therapy , Fluorouracil/therapeutic use , Octreotide/therapeutic use , Pancreatic Neoplasms/drug therapy , Adult , Aged , Aged, 80 and over , Antimetabolites, Antineoplastic/administration & dosage , Antimetabolites, Antineoplastic/adverse effects , Antineoplastic Agents, Hormonal/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Disease Progression , Female , Fluorouracil/administration & dosage , Fluorouracil/adverse effects , Humans , Leucovorin/administration & dosage , Leucovorin/adverse effects , Male , Middle Aged , Octreotide/adverse effects , Survival Rate
5.
Am J Clin Oncol ; 22(5): 517-22, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10521070

ABSTRACT

Paclitaxel is an antimicrotubule agent that interferes with cell division. It has demonstrated promising single-agent activity against non-small-cell lung cancer. The purpose of this study was to evaluate the therapeutic effectiveness of paclitaxel in previously untreated patients with extensive stage small-cell lung cancer (SCLC). The study was designed as a two-stage phase II trial. All patients who entered received paclitaxel by intravenous infusion at a dose of 250 mg/m2 during 24 hours. Granulocyte colony stimulating factor was also provided to ameliorate neutropenia. Cycles were repeated at 21-day intervals. Patients who achieved a complete response received a maximum of 10 cycles of treatment, whereas those who achieved a partial response/regression continued treatment until progression or undue toxicity developed. Patients who progressed or maintained stable disease for six cycles were crossed over to cisplatin and etoposide. Forty-three patients entered the study and all were evaluable for analysis. Responses were observed in 23 (53%) of the patients. There was no significant difference in the response rates in patients with measurable or evaluable disease (13/23 versus 10/20, p = 0.76). At the time of analysis, 39 patients had progressed with a median time to progression of 95 days, and 39 patients had died with a median survival of 278 days. The 1-year achieved survival rate was 24%. Significant neutropenia (absolute neutrophil count <1,000/microl) occurred in 24 (56%) of the patients, but only 2 patients experienced severe infection (grade > or = 3), and there were no septic deaths. The results indicate that paclitaxel is active against SCLC. Myelosuppression was the main side effect in this patient population. Response duration was short (median = 3.4 months), which suggests that paclitaxel is not sufficient as a single agent. Further studies of paclitaxel in combination with other agents against SCLC are currently in progress within the North Central Cancer Treatment Group and other cancer treatment groups. Key Words: Paclitaxel-G-CSF-Small-cell lung cancer-North Central Cancer Treatment Group.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Carcinoma, Small Cell/drug therapy , Lung Neoplasms/drug therapy , Paclitaxel/therapeutic use , Adult , Aged , Aged, 80 and over , Carcinoma, Small Cell/mortality , Disease Progression , Female , Granulocyte Colony-Stimulating Factor/therapeutic use , Humans , Lung Neoplasms/mortality , Male , Middle Aged , Neutropenia/chemically induced , Neutropenia/prevention & control , Survival Rate , United States/epidemiology
6.
J Clin Oncol ; 16(11): 3662-73, 1998 Nov.
Article in English | MEDLINE | ID: mdl-9817289

ABSTRACT

PURPOSE: We report on a clinical trial developed to compare four different instruments that provide overall quality-of-life (QOL) scores, ranging from a simple, one-item instrument to more detailed instruments. Two issues addressed were (1) Will QOL tools suffer from missing data when used in a community-based cooperative group setting?, and (2) Are there additional data generated by a more detailed multiitem instrument over that provided by a single-item global QOL question? MATERIALS AND METHODS: A four-arm randomized trial was designed to compare four instruments that provide overall QOL scores in patients with advanced colorectal cancer. Patients and physicians completed the single-item Spitzer Uniscale (UNISCALE) at baseline and monthly. Patients were randomly assigned to complete, in addition, either the 22-item Functional Living Index-Cancer (FLIC), the five-item Spitzer QOL index (QLI), a picture-face scale (PICT), or nothing else. RESULTS: A total of 128 patients were randomized. Greater than 90% complete QOL data were obtained. There was strong correlation, concordance, and criterion-related validity among all four patient-completed tools. The UNISCALE had a greater decrease over time than did the FLIC (P=.005), which suggests a greater sensitivity; the UNISCALE was similar to the QLI and the PICT in this regard. Physicians provided lower UNISCALE scores than patients. Results supported the hypothesis that QOL is prognostic for survival. CONCLUSION: Patients can effectively complete QOL tools in a cooperative group setting with proper education of health care providers and patients. A simple single-item tool (UNISCALE) appears to be appropriate to obtain a measure of overall QOL.


Subject(s)
Colorectal Neoplasms/diagnosis , Health Status , Quality of Life , Body Weight , Colorectal Neoplasms/mortality , Colorectal Neoplasms/psychology , Evaluation Studies as Topic , Humans , Prognosis
7.
J Neurooncol ; 30(3): 243-6, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8943099

ABSTRACT

Thirty patients with recurrent primary brain tumors were treated with a combination of 5-fluorouracil and leucovorin. There were three responses seen. Toxicity consisted of stomatitis, diarrhea, and hematological suppression. 5-fluorouracil and leucovorin would appear to be minimally effective in recurrent brain tumors.


Subject(s)
Antidotes/therapeutic use , Antimetabolites, Antineoplastic/therapeutic use , Astrocytoma/drug therapy , Brain Neoplasms/drug therapy , Fluorouracil/therapeutic use , Leucovorin/therapeutic use , Oligodendroglioma/drug therapy , Adult , Aged , Antidotes/toxicity , Antimetabolites, Antineoplastic/toxicity , Female , Fluorouracil/toxicity , Humans , Leucovorin/toxicity , Leukopenia/chemically induced , Male , Middle Aged , Recurrence , Stomatitis/chemically induced , Thrombocytopenia/chemically induced
8.
J Clin Oncol ; 14(1): 135-41, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8558188

ABSTRACT

PURPOSE: Megestrol acetate has been reported to improve appetite and quality of life and to decrease nausea and vomiting in patients with cancer anorexia/cachexia. The present trial was formulated to evaluate the impact of megestrol acetate on quality of life, toxicity, response, and survival in individuals with extensive-stage small-cell lung cancer who received concomitant chemotherapy. PATIENTS AND METHODS: Patients were randomized to receive megestrol acetate 800 mg/d orally or placebo. In addition, all patients were scheduled to receive a maximum of four cycles of cisplatin and etoposide chemotherapy. Quality of life was self-assessed at entry onto study, with every cycle of chemotherapy, and 4 months thereafter with a linear visual analog scale. Toxicity was evaluated by patient questionnaire and investigator reports. RESULTS: A total of 243 eligible patients were randomized. Those who received megestrol acetate had increased nonfluid weight gain (P = .004) and significantly less nausea (P = .0002) and vomiting (P = .02). Significant thromboembolic phenomena occurred more often in patients who received megestrol acetate versus placebo (9% v 2%, P = .01). Patients who received megestrol acetate had more edema (30% v 20%, P = .002), an inferior response rate to chemotherapy (68% v 80%, P = .03), and a trend for inferior survival duration (median, 8.2 v 10.0 months, P = .49). These findings may have been influenced by a poorer quality of life of the megestrol acetate group at study initiation. There were no significant changes in quality of life scores over time between either of the study arms. CONCLUSION: Megestrol acetate cannot be routinely recommended for all patients with small-cell lung cancer at the time of chemotherapy initiation. Rather, its therapeutic ratio may be more favorable for patients with problematic cancer anorexia/cachexia.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Small Cell/drug therapy , Lung Neoplasms/drug therapy , Megestrol/analogs & derivatives , Quality of Life , Anorexia/etiology , Anorexia/prevention & control , Bone Marrow/drug effects , Cachexia/etiology , Cachexia/prevention & control , Carcinoma, Small Cell/complications , Carcinoma, Small Cell/mortality , Cisplatin/administration & dosage , Double-Blind Method , Drug Administration Schedule , Etoposide/administration & dosage , Humans , Lung Neoplasms/complications , Lung Neoplasms/mortality , Megestrol/adverse effects , Megestrol/therapeutic use , Megestrol Acetate , Pain Measurement , Survival Analysis , Survival Rate , Thromboembolism/chemically induced
9.
Cancer ; 74(6): 1733-8, 1994 Sep 15.
Article in English | MEDLINE | ID: mdl-8082075

ABSTRACT

BACKGROUND: Doxorubicin generally is considered to be the most effective single chemotherapeutic agent for the treatment of breast cancer. The major cumulative dose-limiting toxicity is cardiac toxicity, which may be related to the formation of free radicals with subsequent lipid peroxidation, leading to membrane damage. The anthrapyrazoles, of which piroxantrone is a member, were synthesized in an attempt to eliminate this toxicity. METHODS: A Phase II clinical trial was conducted in 30 women with metastatic breast cancer in whom piroxantrone was administered at a dose of 160 mg/m2 by 1-hour infusion. The planned cycle length for retreatment was 3 weeks. Measurable metastatic disease and failure on one prior chemotherapy regimen, but no prior anthracycline exposure, were required for response evaluation. RESULTS: Twenty-nine patients were evaluable for response, and 6 (21% and 95% confidence intervals: 10-43%) achieved an objective response (1 complete, 5 partial responses), with a median response duration of 244 days. The median time-to-disease progression for all patients was 124 days. Eight patients received cumulative doses of piroxantrone approaching or exceeding 1000 mg/m2, and all had reductions in the resting left ventricular ejection fraction (LVEF). The estimated median decrease in LVEF at 1000 mg/m2 was 16%, with a range of 10-28%. Clinical findings of congestive heart failure developed in two patients. CONCLUSIONS: Piroxantrone had definite antitumor activity in women who had metastatic breast cancer and failure on prior chemotherapy that did not include an anthracycline. The 95% confidence interval for response probability was broad, but the level of activity observed was relatively low. The clear association with cardiac toxicity combined with the relatively low efficacy led to the conclusion that piroxantrone cannot be recommended for further development as therapy for women with breast cancer. Further study of other anthrapyrazoles is necessary to determine if the promise of this new class of agents can be fulfilled.


Subject(s)
Anthraquinones/therapeutic use , Antineoplastic Agents/therapeutic use , Breast Neoplasms/drug therapy , Pyrazoles/therapeutic use , Adult , Aged , Aged, 80 and over , Anthraquinones/adverse effects , Antineoplastic Agents/adverse effects , Female , Humans , Middle Aged , Pyrazoles/adverse effects , Ventricular Function, Left/drug effects
10.
J Clin Oncol ; 12(6): 1126-9, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8201374

ABSTRACT

PURPOSE: Hydrazine sulfate, an agent that appears to inhibit gluconeogenesis, has been studied in cancer patients for approximately 20 years. There was a recent resurgence of interest in this drug when subset analysis of a small placebo-controlled, double-blind, clinical trial reported improved survival among non-small-cell lung cancer patients with a good performance status who were randomized to receive this drug along with standard chemotherapy. PATIENTS AND METHODS: Patients on this trial had newly diagnosed, unresectable non-small-cell lung cancer and were treated with cisplatin and etoposide. In addition, they were randomized to receive hydrazine sulfate or placebo in a double-blind manner. RESULTS: A total of 243 patients were randomized. Response rates were similar in the two treatment arms. There were trends for worse time to progression and survival in the hydrazine sulfate arm. No significant differences were noted in the two study arms with regard to toxicity or quality of life (QL). CONCLUSION: This trial failed to demonstrate any benefit for patients who received hydrazine sulfate.


Subject(s)
Antineoplastic Agents/therapeutic use , Carcinoma, Non-Small-Cell Lung/drug therapy , Hydrazines/therapeutic use , Lung Neoplasms/drug therapy , Antineoplastic Agents/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/mortality , Cisplatin/administration & dosage , Double-Blind Method , Etoposide/administration & dosage , Female , Humans , Hydrazines/adverse effects , Lung Neoplasms/diagnosis , Lung Neoplasms/mortality , Male , Quality of Life , Survival Rate
11.
J Clin Oncol ; 12(6): 1121-5, 1994 Jun.
Article in English | MEDLINE | ID: mdl-8201373

ABSTRACT

PURPOSE: Hydrazine sulfate is a controversial agent that was originally studied in cancer patients approximately 20 years ago. Based on a series of recent trials that suggested that this drug might have utility in cancer patients, we conducted this study. PATIENTS AND METHODS: Patients with metastatic colorectal cancer were randomized to receive hydrazine sulfate or placebo in a double-blinded manner. Protocol patients did not concurrently receive any other systemic antineoplastic treatment. RESULTS: There were 127 assessable patients entered onto this clinical trial. Data from the study showed trends both for poorer survival and for poorer quality of life (QL) in the hydrazine group. There were no significant differences in the two study arms with regard to anorexia or weight loss. CONCLUSION: This trial failed to demonstrate any benefit for hydrazine sulfate.


Subject(s)
Antineoplastic Agents/therapeutic use , Colorectal Neoplasms/drug therapy , Hydrazines/therapeutic use , Aged , Antineoplastic Agents/adverse effects , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , Double-Blind Method , Female , Humans , Hydrazines/adverse effects , Male , Middle Aged , Quality of Life , Survival Rate
13.
Blood ; 72(4): 1278-85, 1988 Oct.
Article in English | MEDLINE | ID: mdl-3167208

ABSTRACT

Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane-associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs.


Subject(s)
Anemia, Sickle Cell/blood , Erythrocyte Membrane/metabolism , Iron/blood , Lipid Peroxides/blood , Phospholipids/blood , Quinones , Adsorption , Butylated Hydroxytoluene/analogs & derivatives , Erythrocyte Membrane/drug effects , Erythrocytes, Abnormal/drug effects , Erythrocytes, Abnormal/metabolism , Ferrozine , Heme/metabolism , Humans , Iron/physiology , Kinetics , Liposomes , Membrane Lipids/blood , Peroxides
14.
Blood ; 71(4): 876-82, 1988 Apr.
Article in English | MEDLINE | ID: mdl-3355895

ABSTRACT

It has been suggested that the development of sickle RBC membrane defects might be related to abnormal amounts of membrane-associated heme (a term we use in its generic sense to include hemoglobins, hemichromes, and free heme). Techniques previously used to measure membrane heme, however, would not distinguish between what is truly membrane-associated and what is merely trapped in RBC ghost preparations. Consequently, we have examined extensively washed inside-out membranes (IOM) prepared from normal and sickle RBC. Approximately 25% of the sickle ghost heme is lost upon conversion to IOM, but sickle IOM still have a significant excess (1.6 +/- 0.3 nmol heme/mg membrane protein compared with 0.7 +/- 0.2 nmol/mg for normal IOM, P less than .001). Amounts of ghost heme are only poorly predictive of amounts of IOM heme (r = .664). Preparation of IOM by using isotonic lysis with saponin yields virtually identical amounts of IOM heme. Small amounts of heme (less than 15%) can be displaced from IOM by using manipulations that elute spectrin, displace electrostatically bound proteins, or cleave the cytoplasmic portion of band 3. Treatment of IOM with dithiothreitol (DTT), however, displaces the most heme (35%), and this is almost reproduced (25% displacement) by the treatment of intact RBC with DTT before IOM preparation. Sequential treatment with all manipulations still leaves about 40% of the heme in sickle IOM, which indicates a compartment more intimately associated with the membrane. At least part of this is free heme without globin, as evidenced by abnormal binding of radiochloroquine to sickle IOM. Conversely, some IOM-associated globin is globin without heme because the measurement of globin per se markedly overpredicts amount of IOM heme. There is a strong correlation between RBC density and amounts of either ghost or IOM heme. Finally, the amount of membrane thiol oxidation (as measured by thiol-disulfide-exchange chromatography) does not correlate at all with ghost heme (r = .105), but it correlates well with IOM heme (r = .877, P less than .001). These data demonstrate that there are abnormal amounts of heme truly associated with sickle RBC membranes, and they are consistent with the hypothesis that this membrane-associated heme participates in the pathobiology of the sickle RBC membrane, particularly those aspects perhaps related to thiol oxidation.


Subject(s)
Anemia, Sickle Cell/blood , Erythrocyte Membrane/physiology , Erythrocytes, Abnormal/metabolism , Heme/physiology , Sulfhydryl Compounds/blood , Anemia, Sickle Cell/pathology , Erythrocyte Membrane/metabolism , Erythrocyte Membrane/pathology , Erythrocytes, Abnormal/pathology , Heme/analysis , Hemeproteins/physiology , Humans , Membrane Proteins/blood , Membrane Proteins/physiology , Oxidation-Reduction
15.
Clin Nephrol ; 16(4): 172-80, 1981 Oct.
Article in English | MEDLINE | ID: mdl-7028336

ABSTRACT

Nine patients with Wegener's granulomatosis have developed chronic renal failure and undergone chronic hemodialysis and transplantation. These patients are all young (less than 43 years); all except one are male. They present with acute renal failure that resolves with hemodialysis and immunosuppression, but then slowly develop chronic renal failure in spite of adequate immunosuppression. On chronic dialysis no manifestations of Wegener's granulomatosis occur despite low or no immunosuppression in most of them. After transplantation the usual post-transplant immunosuppression regimen (azathioprine and prednisone) not only prevents rejection, but also controls the disease. In only one patient has it been necessary to change from azathioprine to cyclophosphamide because of recurrence.


Subject(s)
Granulomatosis with Polyangiitis/complications , Kidney Failure, Chronic/etiology , Adult , Granulomatosis with Polyangiitis/therapy , Humans , Kidney Failure, Chronic/therapy , Kidney Transplantation , Male , Prednisone/therapeutic use , Renal Dialysis
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