[125I] N6-p-hydroxyphenylisopropyladenosine,a new ligand for Ri adenosine receptors

Summary N⁶-p-Hydroxyphenylisopropyladenosine (HPIA) has been labelled with carrier-free Na[¹²⁵I] to very high specific activity (2,175 Ci/mmol) and used as an agonist ligand to characterize R_i adenosine receptors in rat cerebral cortex membranes. The binding is saturable, reversible, stereospecific and dependent on protein concentration. The specific binding at 37°C was of high affinity with an equilibrium dissociation constant K_D of 0.48 nmol/l and was saturable with 0.23 pmol of [¹²⁵I]HPIA per mg of protein. The rate constant of association, k₁, was 3.25×10⁸ l mol^–1 min^–1 and that of dissociation, k₂, 0.0110 min^–1 yielding a t_1/2 of 63 min. In competition experiments the (–)isomer of N⁶-phenylisopropyladenosine (PIA) was 16-fold more potent than the (+)isomer in competing for the binding sites. Specific binding was most effectively displaced by N⁶-cyclohexyladenosine (CHA, k_i=0.26 nmol/l), (–)PIA (k_i=0.33 nmol/l) and HPIA (k_i=0.52 nmol/l), whereas 5-N-ethylcarboxamidoadenosine (NECA, k_i-1.42 nmol/l) was less effective. The methylxanthines 3-isobutyl-1-methylxanthine (IBMX), theophylline and caffeine which have been classified as adenosine antagonists had k_i values between 5–34 mol/l. Binding of [¹²⁵I]HPIA was regulated by guanine nucleotides and divalent cations. The results indicate that [¹²⁵I]HPIA labels R_i adenosine receptors in rat brain membranes.     

HER2-targeted therapy reduces incidence and progression of midlife mammary tumors in female murine mammary tumor virus huHER2-transgenic mice.

PURPOSE: This study examined the effectiveness of early and prolonged mu4D5 (the murine form of trastuzumab/Herceptin) treatment in transgenic mice that overexpress human HER2 (huHER2), under the murine mammary tumor virus promoter, as a model of huHER2-overexpressing breast cancer. EXPERIMENTAL DESIGN: Mice were randomly assigned to one of three treatment groups and received i.p. injections from 17 weeks of age until either 52 weeks of age or morbidity. Fourteen mice received 100 mg/kg mu4D5, 14 mice received 100 mg/kg antiherpes simplex virus glycoprotein D control antibody, and 11 mice received a diluent control. RESULTS: High levels of huHER2 expression were detectable in mammary glands of young virgin founder mice. Mammary adenocarcinomas were frequently found in female founders and progeny at an average age of 28 weeks, with some progressing to metastatic disease. The incidence of mammary tumors was significantly reduced, and tumor growth inhibition was observed in mice receiving mu4D5 compared with control mice. In addition, Harderian gland neoplasms, highly associated with overexpression of huHER2 in this transgenic line, were entirely absent in the mu4D5 treatment group, indicating down-regulation of huHER2 in vivo activity. CONCLUSIONS: Early intervention with mu4D5 was of benefit in our transgenic mice at high risk for developing huHER2-overexpressing breast cancer. This study suggests a potential benefit of early treatment with Herceptin in HER2-positive primary breast cancer.     

Primary metastatic osteosarcoma: presentation and outcome of patients treated on neoadjuvant Cooperative Osteosarcoma Study Group protocols.

PURPOSE: To determine demographic data and define prognostic factors for long-term outcome in patients presenting with high-grade osteosarcoma of bone with clinically detectable metastases at initial presentation. PATIENTS AND METHODS: Of 1,765 patients with newly diagnosed, previously untreated high-grade osteosarcomas of bone registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies before 1999, 202 patients (11.4%) had proven metastases at diagnosis and therefore were enrolled onto an analysis of demographic-, tumor-, and treatment-related variables, response, and survival. The intended therapeutic strategy included pre- and postoperative multiagent chemotherapy as well as aggressive surgery of all resectable lesions. RESULTS: With a median follow-up of 1.9 years (5.5 years for survivors), 60 patients were alive, 37 of whom were in continuously complete surgical remission. Actuarial overall survival rates at 5 and 10 (same value for 15) years were 29% (SE = 3%) and 24% (SE = 4%), respectively. In univariate analysis, survival was significantly correlated with patient age, site of the primary tumor, number and location of metastases, number of involved organ systems, histologic response of the primary tumor to preoperative chemotherapy, and completeness and time point of surgical resection of all tumor sites. However, after multivariate Cox regression analysis, only multiple metastases at diagnosis (relative hazard rate [RHR] = 2.3) and macroscopically incomplete surgical resection (RHR = 2.4) remained significantly associated with inferior outcomes. CONCLUSION: The number of metastases at diagnosis and the completeness of surgical resection of all clinically detected tumor sites are of independent prognostic value in patients with proven primary metastatic osteosarcoma.     

Effect of acupuncture compared with placebo-acupuncture at P6 as additional antiemetic prophylaxis in high-dose chemotherapy and autologous peripheral blood stem cell transplantation: a randomized controlled single-blind trial.

PURPOSE: The purpose is to investigate an additional antiemetic effect to ondansetron with needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture in patients undergoing high-dose chemotherapy and autologous peripheral blood stem cell transplantation. EXPERIMENTAL DESIGN: Eighty patients who were admitted to hospital for high-dose chemotherapy and autologous peripheral blood stem cell transplantation were included into a randomized placebo-controlled single-blind trial. The patients were randomized to receive acupuncture (n = 41) or noninvasive placebo acupuncture (n = 39) at the acupuncture point P6 30 min before first application of high-dose chemotherapy and the day after. All patients received 8 mg ondansetron/day i.v. as basic antiemetic prophylaxis. The main outcome measure was the rate of patients who either had at least one episode of vomiting or required any additional antiemetic drugs on the first 2 days of chemotherapy. RESULTS: The main outcome measure showed no significant difference (P = 0.82): 61% failure in the acupuncture group and 64% in the placebo acupuncture group (95% confidence interval of 3% difference: -18.1 and 24.3%). Comparing nausea, episodes of vomiting or retching and number of additionally required antiemetic drugs did not provide any discrepancy with the main result. CONCLUSIONS: This study suggests that in combination with ondansetron i.v., invasive needle acupuncture at P6 compared with nonskin-penetrating placebo acupuncture has no additional effect for the prevention of acute nausea and vomiting in high-dose chemotherapy.     

Morphologic dysplasia in de novo acute myeloid leukemia (AML) is related to unfavorable cytogenetics but has no independent prognostic relevance under the conditions of intensive induction therapy: results of a multiparameter analysis from the German AML Cooperative Group studies.

PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account.     

Flat-panel volume computed tomography for cochlear implant electrode array examination in isolated temporal bone specimens.

HYPOTHESIS: Flat-panel based volume computed tomography could improve cochlear implant electrode evaluation in comparison with multislice computed tomography. BACKGROUND: Flat-panel based volume computed tomography offers higher spatial resolution and less metal artifacts than multislice computed tomography. Both characteristics could improve the evaluation of challenging but important questions in cochlear implantation assessment, such as an exact imaging of cochlea, osseous spiral lamina, electrode array position, and single electrode contacts. These questions are not currently fully answered by multislice computed tomography. METHODS: Four isolated temporal bone specimens were scanned in a current multislice computed tomography scanner and in two experimental flat-panel based volume computed tomography scanners before and after cochlea implantation. To compare flat-panel based volume computed tomography and multislice computed tomography, four features were rated according to the following criteria: 1) visibility of the cochlea; 2) visibility of the osseous spiral lamina; 3) discernibility of individual electrode contacts; and 4) the ability to determine the electrode array position relative to scala tympani and scala vestibuli. Layer-by-layer microgrinding pictures were used as the ground truth for verification of imaging findings. RESULTS: Flat-panel based volume computed tomography was superior to multislice computed tomography in all four features rated. The cochlea and facial nerve canal were much better delineated in flat-panel based volume computed tomography. The osseous spiral lamina and single electrode contacts were only visible in flat-panel based volume computed tomography. Assessment of implant position with regard to the cochlear spaces was considerably improved by flat-panel based volume computed tomography. CONCLUSION: Cochlear implantation assessment could be improved by flat-panel based volume computed tomography and, therefore, would be highly beneficial for cochlea implantation research and for clinical evaluation. However, these first results were shown by scanning isolated temporal bone specimens; scanning whole human skull bases might be more challenging.     

Fludarabine in combination with alemtuzumab is effective and feasible in patients with relapsed or refractory B-cell chronic lymphocytic leukemia: results of a phase II trial.

PURPOSE: To determine the efficacy and safety of a newly developed concomitant administration of fludarabine and alemtuzumab (FluCam) in patients with relapsed or refractory B-cell chronic lymphocytic leukemia (B-CLL). PATIENTS AND METHODS: A total of 36 patients were treated in this phase II study (median age, 61.47 years; mean number of prior chemotherapies, 2.6; Binet stage C, n = 28). After an initial dose escalation of alemtuzumab over 3 days, alemtuzumab 30 mg and fludarabine 30 mg/m2 were administered on 3 consecutive days. Treatment was repeated after 28 days for up to six cycles. Restaging (following National Cancer Institute criteria) was carried out after cycles 2 and 4 and 1 month after the end of treatment. RESULTS: The overall response rate was 83% (11 complete responses, 19 partial responses, one stable disease, and five progressive diseases). Two patients with progressive disease developed fungal pneumonias, and one patient died as a result of Escherichia coli sepsis. Two subclinical cytomegalovirus reactivations occurred. CONCLUSION: The new FluCam regimen is effective and feasible in patients with relapsed and refractory B-CLL.     

Osteosarcoma relapse after combined modality therapy: an analysis of unselected patients in the Cooperative Osteosarcoma Study Group (COSS).

PURPOSE: To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma. PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients). RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy. CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome.     

High-dose ara-C and etoposide in refractory or relapsing acute leukemia

Summary A total of 32 patients (15 men and 17 women) presenting with relapsing or refractory acute leukemia were treated with a 3-h infusion of 3 g/m² cytosine arabinoside (ara-C) twice daily on days 1–6 and a 1-h infusion of 100 mg/m² etoposide on days 1–5. In all, 6 subjects had acute lymphocytic leukemia (ALL); 25 had acute myeloid leukemia (AML) of types M1 (n=6), M2 (n=10), M4 (n=5), and M5 (n=4); and 1 had mixed-type leukemia. The median age was 35 years (ranges, 16–62 years). Of the patients presenting with AML, 11 were primarily refractory and 3 became refractory after their first relapse. Six subjects had an early first relapse following a complete remission (CR) that lasted <6 months and five, a second relapse. Another patient underwent a primary relapse after >6 months but had been heavily pretreated. In all, 5 subjects with refractory AML achieved a CR [36%; 95% confidence interval (CI), 10%–62%) as did 7 patients exhibiting relapsing AML (58%; CI, 30%–86%). Three patients who had relapsing or resistant ALL achieved a CR. Side effects consisted of severe hematotoxicity associated with granulocytopenia of <500/mm³ that lasted for a mean of 23.6 days and thrombocytopenia of <20,000/mm³ whose mean duration was 20.8 days. Marked gastrointestinal toxicity and infections were also prevalent. Cutaneous and ocular toxicity as well as allergic, pulmonary and cerebellar side effects were observed in a few cases. We conclude that the combination of high-dose ara-C and etoposide is a powerful but toxic induction regimen for refractory or relapsed acute leukemia.