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E Reed

Publications and source records attributed to E Reed.

At least 19 recordsLinked to original sources

A phase I study of the somatostatin analogue somatuline in patients with metastatic hormone-refractory prostate cancer.

BACKGROUND: Somatuline, a somatostatin analogue, has proven to be effective in several animal models of prostate cancer. Preliminary clinical studies also have suggested antitumor activity in patients with prostate cancer. The authors conducted a dose-escalation trial of 25 patients with metastatic hormone-refractory prostate cancer. METHODS: Dosages of 4, 7, 10, 13, 18, and 24 mg/day were administered by continuous intravenous infusion for at least 28 days. RESULTS: Plasma levels of insulin-like growth factor-I (IGF-I), but not those of IGF-II, declined modestly during therapy. Toxicities included grade I diarrhea, bloating, infection, nausea, and flatus. The gastrointestinal side effects were typically self-limiting and occurred during the initial portion of treatment cycles. In addition, three patients experienced grade II catheter-related infections. No clinical response was noted by either radiographic or tumor marker criteria. The maximally tolerated dose of somatuline was not determined. CONCLUSION: A continuous intravenous infusion of 24 mg/day of somatuline is well tolerated and could be evaluated in other types of cancer or possibly in less advanced prostate cancer, but no clinical activity was noted at this dose in patients with advanced metastatic hormone-refractory prostate cancer.

Aged

Malignant and nonmalignant brain tissues differ in their messenger RNA expression patterns for ERCC1 and ERCC2.

Perturbation of the DNA repair process appears to be responsible for the occurrence of a number of human diseases, which are usually associated with a propensity to develop internal malignancies and/or disorders of the central nervous system. We have been interested in the possibility that a subtle abnormality in DNA repair competency might be associated with the transformation of nonmalignant cells to the malignant state. To study this question, we assayed malignant and nonmalignant brain tissues from 19 individuals for mRNA expression levels of the human DNA repair genes ERCC1, ERCC2, and XPAC and for differential splicing of the ERCC1 transcript. We separately compared expression levels of these genes in the following situations: concordance of expression within malignant tissues; concordance of expression within nonmalignant tissues; concordance between malignant and nonmalignant tissues within individuals of the cohort; and concordance of gene expression between two nonmalignant tissue sites within a single individual. Linear regression analyses of mRNA values obtained suggested orderly concordance of these three DNA repair genes in nonmalignant tissues within the patient cohort and an excellent concordance of these genes between two separate biopsy sites from the same individual. In contrast, malignant tissues showed disruption of concordance between the full-length ERCC1 transcript and ERCC2, which have excision and helicase functions, respectively. Furthermore, within the same individuals, malignant tissues were discordant with nonmalignant tissues for ERCC1 and ERCC2, although concordance for XPAC was preserved. These data suggest that one molecular characteristic of human malignancy may be the disruption of the normal relationship between the excision and the helicase functions of the nucleotide excision repair pathway.

Brain

Effect of cadmium on human ovarian cancer cells with acquired cisplatin resistance.

Cadmium (Cd) dichloride is a compound that has teratogenic, mutagenic, and carcinogenic properties. Recent reports have suggested the possibility that this compound may also have tumor suppressive properties in some settings. For these reasons, we have studied the subcellular pharmacological profile of elemental cadmium in human ovarian cancer cells, when administered as cadmium dichloride. The cell lines A2780 and A2780/CP70 were used, which are well characterized with respect to their cellular response to platinum-based compounds. Cd was measured in all experiments with the use of atomic absorbance spectrometry with Zeeman background correction. In both cell lines, there were direct relationships between; drug dose and cellular accumulation of drug; cellular accumulation of drug and DNA damage levels; and DNA damage levels and cytotoxicity. These cell lines differed in that the cisplatin-resistant A2780/CP70 cell line, was also comparatively resistant to cadmium dichloride. This enhanced cellular resistance appeared to be mediated through decreased drug accumulation, and increased cellular tolerance to higher levels of DNA damage. Total genomic DNA repair and cytosolic inactivation of drug appeared not to differ substantively between these two cell lines.

Cadmium

Family-environment risk factors for attention-deficit hyperactivity disorder. A test of Rutter's indicators of adversity.

BACKGROUND: This study investigated whether family-environment risk factors are associated with attention-deficit hyperactivity disorder (ADHD). Compelling work by Rutter and coworkers revealed that it was the aggregate of adversity factors (severe marital discord, low social class, large family size, paternal criminality, maternal mental disorder, and foster care placement) rather than the presence of any single factor that led to impaired development. Based on the work of Rutter, we hypothesized a positive association between indicators of adversity and the diagnosis of ADHD and ADHD-associated impairments. METHODS: We studied 140 ADHD and 120 normal control probands. Subjects were non-Hispanic white boys between the ages of 6 and 17 years. Rutter's indicators of adversity were used to predict ADHD-related psychopathology as well as impaired cognitive and psychosocial functioning. RESULTS: The odds ratio for the diagnosis of ADHD increased as the number of Rutter's adversity index predicted ADHD-related psychopathology (depression, anxiety, and conduct disorder), learning disabilities, cognitive impairment, and psychosocial dysfunction. CONCLUSIONS: A positive association appears to exist between adversity indicators and the risk for ADHD as well as for its associated psychiatric, cognitive, and psychosocial impairments. These findings support the work of Rutter and stress the importance of adverse family-environment variables as risk factors for children with ADHD.

Adolescent

High risk for attention deficit hyperactivity disorder among children of parents with childhood onset of the disorder: a pilot study.

OBJECTIVE: Although well-documented in clinical and epidemiological studies of attention deficit hyperactivity disorder (ADHD) in children, the familial nature of the adult syndrome has not been well investigated. One approach to evaluate the familial nature of adult ADHD is through a high-risk design aimed at estimating the risk for the disorder in children of parents with child-hood-onset ADHD. METHOD: Children at risk for ADHD were ascertained from the study group of 84 referred adults with clinical diagnoses of childhood onset of the disorder, confirmed by structured interviews. Diagnostic information on the disorder was derived from the ADHD module of the Schedule for Affective Disorders and Schizophrenia for School Age Children--Epidemiologic Version, supplemented with information regarding treatment for ADHD for the affected child and school history including repeated grades, placement in special classes, and tutoring. RESULTS: Of the 84 children at risk, 48 (57%) met criteria for ADHD. The rate of the disorder in children of adults with the disorder was significantly higher than the previously reported rate of ADHD among siblings of children with the disorder. Of the 48 ADHD children of parents with the disorder, 36 (75%) were treated for it. The rates of school failure were almost identical to those previously reported in a group of referred children and adolescents with ADHD. CONCLUSIONS: These results support the validity of the adult diagnosis of ADHD and suggest that the adult form of this disorder may have stronger familial etiological risk factors than its pediatric form. If these results are confirmed, families selected through adult probands with ADHD might be especially useful for testing genetic hypotheses about the disorder.

Achievement

Pharmacologic variables associated with the development of neurologic toxicity in patients treated with suramin.

PURPOSE: To describe pharmacologic variables correlated with the development of neurologic toxicity in patients treated with suramin. METHODS: Eighty-one patients were treated with suramin in a phase I study. The rate of drug infusion was continuously adjusted to maintain a preassigned plasma suramin concentration (175, 215, or 275 micrograms/mL) for a fixed duration (2 to 8 weeks). RESULTS: Eight patients developed grade III/IV neurologic motor impairment (predominantly motor axonal polyneuropathy). All were treated at the 275-micrograms/mL concentration. One patient treated at the 215-micrograms/mL concentration developed grade II motor dysfunction. In addition, seven of nine patients had sensory symptoms. Pharmacologic variables associated with the development of polyneuropathy included total cumulative suramin dose, duration of exposure to plasma concentrations greater than 200 micrograms/mL, and area under the curve (AUC) greater than 200 micrograms/mL. CONCLUSION: Significant neurologic toxicity can result from therapy with suramin, even when dosing is designed to avoid exposure to plasma concentrations greater than 350 micrograms/mL. Future clinical trials of suramin should be designed in such a way as to limit the total cumulative dose to < or = 157 mg/kg given over a period of > or = 8 weeks, limit the period of exposure to plasma suramin concentrations greater than 200 micrograms/mL to < or = 25 days, and limit the AUC greater than 200 micrograms/mL to < or = 48,000 mg.h/AL.

Adult

A preliminary risk-benefit assessment of paclitaxel.

Paclitaxel is an antineoplastic agent, first isolated and described in 1971. Despite its novel structure and apparent activity in vitro, little interest was shown in developing the compound because of its scarcity, problems with its formulation and the mistaken assumption that its mechanism of action was similar to that of the vinca alkaloids. Approximately 10 years later, the unique mechanism of action of paclitaxel, its ability to stabilise microtubules, was discovered, and its activity against human tumour xenografts was demonstrated. Interest in the drug was reignited and clinical testing began. Severe hypersensitivity reactions were controlled in the phase II programme with a premedication regimen consisting of dexamethasone, histamine H1-antagonists and H2-antagonists. Neutropenia was dose limiting in all studies conducted in patients with solid tumours. This toxicity was schedule-dependent, and less severe when paclitaxel was administered as a 3-hour infusion regimen. Peripheral neuropathy was mild to moderate in the initial experience, and dose-dependent. However, when bone marrow support with haemopoietic growth factors was used to allow paclitaxel dose intensification, neurotoxicity became dose limiting. To date, substantial clinical efficacy has been demonstrated in ovarian, breast, non-small-cell lung, and head and neck cancers. Response rates were low in initial studies in melanoma, prostate, colon, cervix and renal cancer. In December 1992, US Food and Drug Administration approval was granted for the use of paclitaxel as second-line therapy in ovarian cancer patients. More recently, similar approval was granted for use in recurrent breast cancer. Nevertheless, important questions remain.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Post-transplantation lymphoproliferative disorders arising in solid organ transplant recipients are usually of recipient origin.

Recent clinical, pathological, and molecular studies have increased our understanding of posttransplantation lymphoproliferative disorders (PT-LPDs). Studies have shown that the majority of PT-LPDs arising in bone marrow transplant recipients are of donor origin; however, the source (host or donor) of the lymphoid cells that make up PT-LPDs arising in solid organ transplant recipients has not been systemically investigated. In this study, 18 PT-LPDs occurring in 16 organ transplant recipients (13 heart, 2 kidney, 1 lung), 9 donor tissues (for 10 recipients), and 14 uninvolved recipient tissues (from 12 patients) were examined employing restriction fragment length polymorphism analysis to determine their host or donor origin. The PstI-digested DNAs were analyzed by Southern blot hybridization using two highly informative polymorphic probes that map to chromosome 21 (CRI-PAT-pL427-4) and chromosome 7 (CRI-PAT-pS194). All solid organ PT-LPDs with corresponding uninvolved recipient DNA showed identical hybridization patterns; none of the PT-LPDs exhibited a hybridization pattern that matched donor DNA. These findings suggest that the vast majority of PT-LPDs arising in solid organ transplant recipients, in contrast to those arising in bone marrow transplant recipients, are of recipient origin.

Adolescent

Paclitaxel, cisplatin, and cyclophosphamide in human ovarian cancer: molecular rationale and early clinical results.

The three most active types of agents in the treatment of cancer of the ovary are platinum compounds (cisplatin or carboplatin), bifunctional alkylating agents (cyclophosphamide, melphalan, etc), and the recently developed natural product paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ). In an effort to improve long-term disease-free survival in patients with advanced disease, we have developed a three-drug regimen consisting of cisplatin, paclitaxel, and cyclophosphamide. Granulocyte-colony stimulating factor is given as bone marrow support using a flexible dosing approach. The molecular basis for this approach is founded in the positive molecular interactions between cisplatin and bifunctional alkylating agents and between paclitaxel and DNA-damaging agents. Cisplatin and cyclophosphamide damage DNA by two very different mechanisms; the respective importance of DNA strand "kinking" versus DNA strand "cross-linking" may explain the positive cell kill interaction between these two drugs. Paclitaxel appears to markedly slow the repair of DNA lesions caused by DNA-damaging agents, which may include radiation-induced lesions, cisplatin adducts, and cyclophosphamide cross-links. Clinical data to date from several different groups strongly suggest that these molecular interactions translate into positive clinical benefit in human ovarian cancer. Preliminary data from our clinical trial show that these three agents are well tolerated in the doses administered and that this combination shows exceptional promise as a possible therapeutic advance in this disease.

Antineoplastic Combined Chemotherapy Protocols

Paclitaxel (taxol) inhibits protein isoprenylation and induces apoptosis in PC-3 human prostate cancer cells.

Paclitaxel was examined for its effects on cell survival, internucleosomal DNA fragmentation, and protein isoprenylation in the human prostate cancer cell line PC-3. Treatment of cells with paclitaxel at 5-60 nM for 24 hr resulted in a dose-dependent inhibition of cell viability (IC50, 31.2 nM), which was partially prevented by supplementing the cell culture medium with two nonsterol polyisoprenyl compounds, farnesyl-pyrophosphate (-PP) and geranylgeranyl-PP (3 microM each). Furthermore, agarose gel electrophoresis of DNA extracted from cells treated with paclitaxel (15-60 nM) for 24 hr showed DNA laddering with production of fragments of 180-base pair multiples, indicating the occurrence of apoptotic cell death. Internucleosomal DNA fragmentation by paclitaxel was also detected by a photometric enzyme immunoassay using antihistone antibodies; if culture medium was supplemented with farnesyl-PP and geranylgeranyl-PP (3 microM each), a reduction in mono- and oligonucleosome production was observed. The post-translational incorporation of metabolites of (RS)-[5-3H]mevalonolactone (100 microCi/ml) into prenylated proteins of PC-3 cells was inhibited by paclitaxel at 30 and 60 nM. In addition, the immunoprecipitation of p21ras and p21rap-1 proteins from PC-3 cells exposed to paclitaxel (30 and 60 nM) and labeled with (RS)-[5-3H]mevalonolactone showed a substantial inhibition of the incorporation of farnesyl and geranylgeranyl prenoid groups, respectively, into the aforementioned proteins. These results indicate that the inhibition of protein isoprenylation is a novel component of the complex biochemical effects of the drug and plays an important role in the mechanism of paclitaxel cytotoxicity in PC-3 cells.

Apoptosis

Effects of interleukin-1 alpha on DNA repair in human ovarian carcinoma (NIH:OVCAR-3) cells: implications in the mechanism of sensitization of cis-diamminedichloroplatinum(II).

The cytokine interleukin-1 alpha (IL-1 alpha) showed a cytostatic effect on human ovarian carcinoma cells and significantly enhanced the antiproliferative activity of cis-diamminedichloroplatinum(II) (cisplatin) toward the NIH:OVCAR-3 tumor cell line in culture. The factor of sensitization was 15-20-fold. The maximum levels of sensitization were observed both with simultaneous exposure to cisplatin and IL-1 alpha and with 24-hr pretreatment with IL-1 alpha. Synergy between these agents was diminished when cells were pretreated with an IL-1 alpha-specific receptor antagonist, indicating that synergistic interaction was receptor mediated. Using atomic absorption spectroscopy, we evaluated the cellular accumulation of cisplatin and the DNA platination; the results showed that IL-1 alpha increased cellular accumulation of cisplatin and DNA platination. Cisplatin did not affect IL-1 alpha accumulation in NIH:OVCAR-3 cells. Further studies showed that IL-1 alpha reduced the removal of platinum from DNA. These results strongly suggest that IL-1 alpha inhibits DNA repair, and this decrease in DNA repair may explain, in part, the strong synergistic interaction between IL-1 alpha and cisplatin in NIH:OVCAR-3 cells.

Cisplatin

Acute renal toxicity associated with suramin in the treatment of prostate cancer.

The use of suramin, a polysulfonated naphthylurea, in the treatment of advanced prostate cancer currently is being investigated. A 52-year-old man developed acute renal dysfunction after receiving nine doses of suramin. His suramin therapy was discontinued, but his serum creatinine level continued to rise to 10.8 mg/dl during the next 6 days. The patient was not rechallenged with suramin, and his renal function returned to baseline within the next 3 weeks. Future investigators of this drug should be aware of the possibility of such a reaction with parenteral administration.

Acute Kidney Injury

Platinum-DNA adducts assayed in leukocytes of patients with germ cell tumors measured by atomic absorbance spectrometry and enzyme-linked immunosorbent assay.

BACKGROUND: Platinum-DNA adducts can be measured in peripheral blood cells, and high adduct levels have previously been correlated with favorable clinical response to platinum-based therapy in patients with germ cell tumors and ovarian cancer. METHODS: To evaluate the relationship between platinum-DNA adducts and clinical response to chemotherapy, 36 patients with germ cell tumors treated with cisplatin-based chemotherapy had platinum-DNA adducts assayed in leukocytes by atomic absorption spectrometry (AAS) and cisplatin-DNA enzyme-linked immunosorbent assay (ELISA). Three chemotherapy regimens were involved: cisplatin and etoposide (Regimen A); carboplatin and etoposide (Regimen B); and cyclophosphamide, vinblastine, dactinomycin, bleomycin, and cisplatin [VAB-6] with or without high dose carboplatin plus etoposide plus autologous bone marrow rescue (Regimen C). Blood samples were drawn before and after each cycle of chemotherapy. RESULTS: One hundred ninety-two blood samples were assayed by AAS and 137 by ELISA: DNA adducts measured by AAS and ELISA increased immediately after treatment and decreased during the intervening time before the next treatment. DNA adducts were measurable by both methods 4-8 weeks after the last cycle of therapy. The peak and mean adduct levels measured in samples drawn immediately after Cycles 1 and 2 and after all cycles were analyzed in terms of their relationship to clinical response. In contrast to numerous prior studies, a positive correlation was not observed between DNA adduct formation as determined by either AAS or ELISA and favorable clinical responses. CONCLUSIONS: This study demonstrated that peak and mean platinum-DNA adduct levels were influenced by the dose and schedule of the platinum analogue. For example, treatment with VAB-6 with or without high dose carboplatin and etoposide (Regimen C) resulted in significantly higher adduct levels when measured by AAS compared with Regimen A or B. Inconsistencies between studies regarding observed correlations of DNA adducts and treatment outcome may be attributable to differences in platinum analogue, dose, schedule, and timing of sample procurement. These factors must be considered in future studies.

Adolescent

Flexible granulocyte colony-stimulating factor dosing in ovarian cancer patients who receive dose-intense taxol therapy.

As has been reported with other chemotherapeutic agents, evidence is emerging to suggest that increased taxol dose intensity is associated with improved therapeutic efficacy. Granulocyte colony-stimulating factor (G-CSF) effectively protects the bone marrow from taxol-induced neutropenia and allows for higher taxol dose administration. This report addresses the optimal use of G-CSF as a supportive agent for dose-intense taxol therapy. Forty-seven patients were evaluated. Each ovarian cancer patient received taxol with G-CSF support, with starting doses of 250 mg/m2 per 21 days and 10 micrograms/kg/d, respectively. Five patients were treated with the same dose of G-CSF for multiple cycles. Forty-two patients were given "flexible" G-CSF dosing. Instead of reducing taxol dose after a cycle of therapy complicated by febrile neutropenia (F+N+), the G-CSF dose was increased. Only after a second episode of F+N+ was the taxol dose reduced. The initial 5 patients who developed F+N+ after taxol (250 mg/m2) and G-CSF (10 micrograms/kg/d) were retreated at the same doses of both drugs; subsequently, 4 of 5 patients had another episode of F+N+. With flexible G-CSF dosing, taxol dose intensity could be maintained at the target level in 34 of 42 patients (81% of the cohort). Sixteen of these patients (38% of the cohort) would have required taxol dose reductions for F+N+ if flexible G-CSF dosing had not been used. By increasing the G-CSF dose when indicated, patients at high risk for recurrence of F+N+, because they had already experienced one episode, appeared to have a lower risk of developing a recurrent episode. These data suggest that flexible G-CSF dosing may have merit and may allow the administration of more dose-intense taxol. A prospective, randomized, controlled clinical trial of flexible G-CSF dosing versus fixed-dose G-CSF appears warranted.

Dose-Response Relationship, Drug

Clinical outcome of peripheral blood stem cell support.

Two clinical results of peripheral blood stem cell support are commonly considered: (1) the effect on hematopoietic recovery and (2) the effect on the underlying malignancy. The dynamics of hematopoietic recovery after autologous bone marrow transplantation and after autologous peripheral blood stem cell transplantation in a clinical setting are similar if no exogenous cytokines are administered and the peripheral stem cells are collected while their numbers are not deliberately increased (mobilised). If mobilized peripheral stem cells are transplanted, hematopoietic recovery is accelerated. In some circumstances, patients who receive peripheral stem cell transplantation may experience an improved progression-free survival after high-dose therapy when compared with similar patients who receive autologous bone marrow transplantation. Explanations for such a survival advantage might include (1) a lower likelihood of occult tumor cells capable of restoring disease in peripheral stem cell autograft products than in bone marrow harvests, (2) a greater number of cytotoxic effector cells capable of destroying occult tumor cells in the peripheral stem cell collections than in bone marrow harvests, and (3) a different and advantageous pattern of immunologic recovery following autologous peripheral stem cell transplant compared to autologous bone marrow transplant.

Hematopoietic Stem Cell Transplantation

Messenger RNA levels of XPAC and ERCC1 in ovarian cancer tissue correlate with response to platinum-based chemotherapy.

Nucleotide excision repair is a DNA repair pathway that is highly conserved in nature, with analogous repair systems described in Escherichia coli, yeast, and mammalian cells. The rate-limiting step, DNA damage recognition and excision, is effected by the protein products of the genes ERCC1 and XPAC. We therefore assessed mRNA levels of ERCC1 and XPAC in malignant ovarian cancer tissues from 28 patients that were harvested before the administration of platinum-based chemotherapy. Cancer tissues from patients whose tumors were clinically resistant to therapy (n = 13) showed greater levels of total ERCC1 mRNA (P = 0.059), full length transcript of ERCC1 mRNA (P = 0.026), and XPAC mRNA (P = 0.011), as compared with tumor tissues from those individuals clinically sensitive to therapy (n = 15). In 19 of these tissues, the percentage of alternative splicing of ERCC1 mRNA was assessed. ERCC1 splicing was highly variable, with no difference observed between responders and nonresponders. The alternatively spliced species constituted 2-58% of the total ERCC1 mRNA in responders (median = 18%) and 4-71% in nonresponders (median = 13%). These data suggest greater activity of the DNA excision repair genes ERCC1 and XPAC in ovarian cancer tissues of patients clinically resistant to platinum compounds. These data also indicate highly variable splicing of ERCC1 mRNA in ovarian cancer tissues in vivo, whether or not such tissues are sensitive to platinum-based therapy.

Carboplatin