Comparison of transgene expression in Aedes aegypti generated by mariner Mos1 transposition and ΦC31 site-directed recombination

Transgenic mosquitoes generated by transposable elements (TEs) often poorly express transgenes owing to position effects. To avoid these effects, the ΦC31 site-directed recombination system was used to insert transgenes into a locus favourable for gene expression in Aedes aegypti. We describe phenotypes of mariner Mos1 TE and ΦC31 transgenic mosquitoes expressing the enhanced green fluorescent protein (EGFP) reporter in midguts of blood-fed females. Mosquitoes of nine TE-generated lines [estimated transformation frequency (TF): 9.3%] clearly expressed the eye-specific selection marker but only 2/9 lines robustly expressed the EGFP reporter. The piggyBac TE-generated ΦC31 docking strain, attP26, supported recombination with attB site containing donors at an estimated TF of 1.7-4.9%. Using a codon-optimized ΦC31 integrase mutant instead of the 'wild-type' enzyme did not affect TF. Site-directed recombination of line attP26 with an attB-containing donor expressing EGFP from the Ae. aegypti carboxypeptidase promoter produced one transgenic line with blood-fed females expressing the reporter in midgut tissue. Docking strain attP26 also supported robust expression of Flock House virus B2 from the Ae. aegypti polyubiquitin promoter. Our data confirm that eye-specific selection marker expression alone is not a reliable indicator for robust gene-of-interest expression in Ae. aegypti and that the ΦC31 system can ensure predictable transgene expression in this mosquito species.

Excite and receive solenoid radiofrequency coil for MRI-guided breast interventions

A radiofrequency coil based on a solenoid design was developed and integrated with a novel device for MR-guided breast interventions using a circumferential approach. The transmit/receive tapered solenoid design conforms to the shape of the pendent breast, and provides open circumferential needle access to breast tissue under rotational symmetry. Phantom and in vivo studies using a healthy volunteer demonstrated a superior uniformity using the tapered solenoid coil compared with a commercial 8-channel diagnostic imaging coil. The solenoid coil design has important advantages due to localized transmit/receive such as B(1) -homogeneity and reduced specific absorption ratio (SAR) especially at high-field strengths. Because it provides open access and a rotationally symmetric local field, the tapered solenoid design can easily be adapted for bilateral imaging and 3D MR-guided breast interventions.

Should there be a standard therapy for mantle cell lymphoma?

Mantle cell lymphoma (MCL) is an uncommon subtype of B-cell lymphomathat is characterized by monoclonal B cells that express CD5 on their surface, but not CD23, and harbor the t(11:14) chromosomal translocation that leads to dysregulated expression of cyclin D1. MCL is a biologically and clinically heterogeneous disease. It has the unfavorable characteristics of both aggressive and indolent lymphoma in that MCL is not curable with current standard therapy, yet patients have a shorter survival compared with other indolent histology. MCL is incurable, yet more intensive therapy does lead to longer disease-free intervals; therefore, treatment must be designed to optimize survival while maintaining quality of life. Thus, therapy should be individualized based on both the clinical behavior of the lymphoma and the patient’s status. While there is no clear standard therapy that can be recommended for all patients, there may be an optimal choice for each patient. Knowledge of the expected clinical benefits and toxicities of various approaches will allow the physician and patient to appropriately select the therapy.

A Phase 1b/2 trial of mapatumumab in patients with relapsed/refractory non-Hodgkin's lymphoma

Background:

We conducted a multicentre Phase 1b/2 trial to evaluate the safety and efficacy of mapatumumab, a fully human agonistic monoclonal antibody to the tumour necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1) in patients with relapsed non-Hodgkin's lymphoma (NHL).

Methods:

Forty patients with relapsed or refractory NHL were treated with either 3 or 10 mg kg⁻¹ mapatumumab every 21 days. In the absence of disease progression or prohibitive toxicity, patients received a maximum of six doses.

Results:

Mapatumumab was well tolerated, with no patients experiencing drug-related hepatic or other dose-limiting toxicity. Three patients with follicular lymphoma (FL) experienced clinical responses, including two with a complete response and one with a partial response. Immunohistochemistry staining of the TRAIL-R1 suggested that strong staining in tumour specimens did not appear to be a requirement for mapatumumab activity in FL.

Conclusions:

Mapatumumab is safe and has promising clinical activity in patients with FL.

Tackling mantle cell lymphoma (MCL): Potential benefit of allogeneic stem cell transplantation

Mantle cell lymphoma (MCL) is a type of non-Hodgkins lymphoma (NHL) associated with poor progression-free and overall survival. There is a high relapse rate with conventional cytotoxic chemotherapy. Intensive combination chemotherapy including rituximab, dose intense CHOP- (cyclophosphamide-doxorubicin-vincristine-prednisone) like regimens, high dose cytarabine, and/or consolidation with autologous stem cell transplant (autoSCT) have shown promise in significantly prolonging remissions. Data from phase II studies show that even in patients with chemotherapy refractory MCL, allogeneic stem cell transplant (alloSCT) can lead to long term disease control. Most patients with MCL are not candidates for myeloablative alloSCT due to their age, comorbidities, and performance status. The advent of less toxic reduced intensity conditioning (RIC) regimens, which rely more on the graft-versus-lymphoma (GVL) effect, have expanded the population of patients who would be eligible for alloSCT. RIC regimens alter the balance of toxicity and efficacy favoring its use. Treatment decisions are complicated by introduction of novel agents which are attractive options for older, frail patients. Further studies are needed to determine the role and timing of alloSCT in MCL. Currently, for selected fit patients with chemotherapy resistant MCL or those who progress after autoSCT, alloSCT may provide long term survival.

Acetate as sole carbon and energy source for growth of methanosarcina strain 227

Methanosarcina strain 227 grew rapidly and produced methane on a mineral medium containing acetate as the sole added organic substrate. Cell yields but not doubling times were affected by the presence or absence of yeast extract. Greater cell yields occurred in yeast extract medium than in mineral medium. Radioactive labeling studies showed that acetate was decarboxylated in mineral medium, as was shown previously in complex medium. The specific radioactivity of methane produced per specific acitvity of acetate added was not significantly different in yeast extract medium compared with mineral medium. Unequivocal evidence indicates that the cleavage of acetate to methane and carbon dioxide provided the energy for growth in the presence or absence of other organic compounds; these latter compounds do not serve as energy sources, electron donors, or significant sources of methane during this aceticlastic reaction.

STUDIES ON THE MECHANISM OF RECOVERY IN PNEUMOCOCCAL PNEUMONIA : IV. THE MECHANISM OF PHAGOCYTOSIS IN THE ABSENCE OF ANTIBODY

1. Evidence has been presented in previous publications that the phagocytosis of pneumococci in the pneumonic lung during chemotherapy is due neither to specific opsonins nor to capsular injury (1, 2). The present studies have shown that the phagocytosis taking place in the lung is independent of any sort of intermediary factor and results from a direct action of the phagocytic cells upon the pneumococci. 2. Phagocytosis in the absence of antibody has been demonstrated not only in the lungs of living rats but in formalin-fixed lungs, on the surfaces of a variety of tissues (both freshly removed from the animal and previously "killed" with heat), and on the surfaces of such inert materials as moistened filter paper, cloth, and fiber glass. On the other hand, smooth materials such as glass, cellophane, albumin, and paraffin have failed to support the phagocytic reaction. This latter observation indicates that the physical character of the surface to which the leucocytes have access constitutes a determining factor in the non-antibody mechanism of phagocytosis. 3. Further experiments have defined the relationship of "surface phagocytosis" to that induced by specific opsonins. The non-antibody mechanism was found to operate only upon surfaces of suitable physical properties, whereas opsonins enabled phagocytes floating freely in a fluid medium to engulf the fully encapsulated organisms. 4. Direct visualization of the surface phenomenon in the lung revealed that leucocytes phagocyte the virulent organisms in the absence of antibody only after having trapped them against the alveolar walls. Once the encapsulated pneumococci have been ingested, they can be seen to undergo digestion within a few hours. The discovery of the phenomenon of surface phagocytosis affords clarification of previously unanswered problems concerning the mechanism of recovery in pneumococcal pneumonia.

STUDIES ON THE MECHANISM OF RECOVERY IN PNEUMONIA DUE TO FRIEDLANDER'S BACILLUS : II. THE EFFECT OF SULFONAMIDE CHEMOTHERAPY UPON THE PULMONARY LESION OF EXPERIMENTAL FRIEDLANDER'S BACILLUS PNEUMONIA

Sulfonamide chemotherapy was found to cure rats of an otherwise fatal form of experimental Friedländer's bacillus pneumonia when treatment was begun 6 hours after inoculation. Most of the pneumonic lesions cleared completely, but an occasional animal exhibited small residual abscesses in the previously consolidated lung. The recovery process taking place in the lungs was studied histologically at various intervals during therapy. As in the case of pneumococcal pneumonia, the principal action of the sulfonamide was upon the bacteria in the advancing edema zone at the periphery of the pneumonic lesion. The bacteriostatic action of the drug appeared to stop the spread of the pneumonia, and the Friedländer bacilli were ultimately ingested and destroyed by the phagocytic cells in the alveolar exudate. The phagocytosis of bacteria in the lung was shown to be unrelated to the presence of antibody in the blood.

STUDIES ON THE MECHANISM OF RECOVERY IN PNEUMONIA DUE TO FRIEDLADER'S BACILLUS : III. THE ROLE OF "SURFACE PHAGOCYTOSIS" IN THE DESTRUCTION OF THE MICROORGANISMS IN THE LUNG

Phagocytosis of encapsulated Friedländer's bacilli has been demonstrated in the lungs of rats in the absence of both circulating and local antibody. The mechanism of phagocytosis independent of antibody has been shown to be due to the same surface factors that operate in the phagocytosis of Type I pneumococcus under similar conditions. Direct observation of the phagocytic process reveals that leucocytes in the lung can phagocyte unopsonized Friedländer's bacilli only by trapping them against the surfaces of alveolar walls or bronchi, or by pinning them against the surfaces of adjacent leucocytes. Evidence is presented that Friedländer's bacilli thus phagocyted are rapidly killed in the cytoplasm of the phagocytic cells. Reasons are discussed for the failure of prolonged chemotherapy to cure lung abscesses that not infrequently complicate the pneumonia due to Friedländer's bacillus.

Abstract 3664: Bendamustine induces a dose-dependent cell cycle arrest in Hela cells that results in different mitotic outcomes

Bendamustine (BDM) was originally synthesized in the 1960s but has only recently been approved by the FDA for the treatment of chronic lymphocytic leukemia and B-cell non-Hodgkin lymphoma. BDM consists of a bifunctional alkylating nitrogen mustard group and a benzimidazole ring and has been suggested to have both alkylator and purine analogue activities. Insights into the molecular mechanisms by which efficacy is achieved are scarce. Furthermore, the effects of BDM on solid tumors also remains under-investigated. Here we evaluate the effects of BDM on Hela cells and attempt to discern its effects on the cell cycle. Hela cells were treated with different concentrations of BDM, with the antimetabolite gemcitabine, or with the alkylator MMS. Interestingly, we found dose-dependent effects of BDM on cell cycle progression. Using synchronized cells, we observed that a low dose of BDM blocked cells in G2, similar to MMS, while a 4-fold higher dose of BDM arrested cells in S phase, as seen with gemcitabine.

We next investigated the effect of abrogating the BDM-induced S and G2 cell cycle arrests with the Chk1 inhibitor UCN-01. To track the fates of cells time-lapse microscopy was conducted on cells expressing H2B: GFP. Cells were first arrested in G2 with low BDM or MMS before addition of UCN-01. Cells were observed to enter mitosis, align their chromosomes but then were delayed from entering anaphase. The cells eventually exited mitosis, with a small number of cells displaying lagging chromosomes. In contrast, cells arrested in S phase with high dose BDM or with gemcitabine, followed by UCN-01 showed highly aberrant mitotic figures. Although these cells were also delayed in mitosis, many of them died in mitosis rather than exit. We stained the mitotic cells generated by G2 or S phase inhibitors and found that cells arrested in G2 and forced into mitosis displayed normal looking metaphases, with aligned centromere/kinetochores on the spindle. However, the cells arrested in S phase followed by UCN-01 led to the generation of ‘mitosis with unreplicated genomes’ (MUGs). This phenomenon is characterized by fragmented mitotic chromatin and detached centromeres and kinetochores away from bulk DNA, as confirmed by electron microscopy (see accompanying poster Beeharry et al.). Furthermore, UCN-01 only induces formation of MUGs in cells arrested in with high BDM or gemcitabine. Although cells arrested in G2 by low BDM or MMS can also enter mitosis after UCN-01 treatment, they do not exhibit fragmented centromeres (MUGs).

These observations are consistent with the notion that BDM can act as a nucleoside analogue or as an alkylator, depending on the dose. BDM must therefore inhibit different processes in a dose-dependent manner. Furthermore, tumor cell response may differ depending on the sensitivity of these two cellular processes to BDM. These findings maybe critical for predicting sensitization by inhibitors of Chk1 kinase.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3664.

Pediatric nodal marginal zone lymphoma may develop in the adult population

Pediatric nodal marginal zone lymphoma (NMZL) is described as a separate variant of NMZL in the most recent WHO classification of tumors of hematologic and lymphoid tissues. It has distinctive morphology and clinical presentation and stands out as an indolent disease with remarkably better overall prognosis compared to classic NMZL. Here we report two adult patients with NMZL with clinical and morphologic features consistent with pediatric NMZL (pNMZL) and review available literature describing the clinical and histologic presentation of pNMZL. Two men, ages 44 and 18 years, each presented with localized cervical lymphadenopathy, both demonstrated florid proliferation of the marginal zone and disruption of reactive germinal centers, progressive transformation of germinal centers-like morphologic features typical for pNMZL and clonal disease with immunophenotype consistent with NMZL. This is the first report of pNMZL in a middle-aged person. Distinct histologic features and characteristic benign clinical course will help to distinguish this rare variant from other NMZL in the adults. Clinically, recognition is important to understand the true incidence of this rare form in the adult population and to avoid unnecessary overtreatment of this indolent form.

Safety, pharmacokinetics, and preliminary clinical activity of inotuzumab ozogamicin, a novel immunoconjugate for the treatment of B-cell non-Hodgkin's lymphoma: results of a phase I study

PURPOSE Inotuzumab ozogamicin (CMC-544) is an antibody-targeted chemotherapy agent composed of a humanized anti-CD22 antibody conjugated to calicheamicin, a potent cytotoxic agent. This was a phase I study to determine the maximum-tolerated dose (MTD), safety, and preliminary efficacy of inotuzumab ozogamicin in an expanded MTD cohort of patients with relapsed or refractory CD22(+) B-cell non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS Inotuzumab ozogamicin was administered intravenously as a single agent once every 3 or 4 weeks at doses ranging from 0.4 to 2.4 mg/m(2). Outcomes included MTD, safety, pharmacokinetics, response, progression-free survival (PFS), and overall survival. Results Seventy-nine patients were enrolled. The MTD was determined to be 1.8 mg/m(2). Common adverse events at the MTD were thrombocytopenia (90%), asthenia (67%), and nausea and neutropenia (51% each). The objective response rate at the end of treatment was 39% for the 79 enrolled patients, 68% for all patients with follicular NHL treated at the MTD, and 15% for all patients with diffuse large B-cell lymphoma treated at the MTD. Median PFS was 317 days (approximately 10.4 months) and 49 days for patients with follicular NHL and diffuse large B-cell lymphoma, respectively. CONCLUSION Inotuzumab ozogamicin has demonstrated efficacy against CD22(+) B-cell NHL, with reversible thrombocytopenia as the main toxicity.

Impact of Rituximab (Rituxan) on the Treatment of B-Cell Non-Hodgkin's Lymphoma

Non-Hodgkin's lymphoma (NHL) is the most common hematological malignancy in adults, with B-cell lymphomas accounting for 85% of all NHLs. The most substantial advancement in the treatment of B-cell malignancies, since the advent of combination chemotherapy, has been the addition of the monoclonal anti-CD20 antibody rituximab (Rituxan). Since its initially reported single-agent activity in indolent lymphomas in 1997, the role of rituximab has expanded to cover both indolent and aggressive lymphomas.This article focuses on the impact of rituximab on the treatment, survival, and long-term outcomes of patients with indolent and aggressive lymphomas over the past two decades.

Bone health and prostate cancer

Bone metastases are a substantial burden to men with advanced prostate cancer as they often cause pain and can cause fractures and spinal cord compression. Osteoblasts and osteoclasts are both pathologically activated in the setting of prostate cancer bone metastases. As osteoclast activation is associated with disease progression, skeletal complications and death, osteoclast-targeted therapies are a rational approach to disease management. Zoledronic acid is standard of care for castration-resistant prostate cancer with bone metastases as it reduces the risk for skeletal-related events. Additional trials are needed to better define the ideal dose, frequency and duration of zoledronic acid therapy. No bisphosphonate has yet been shown to prevent bone metastases or to benefit men with androgen-sensitive disease. Denosumab is an experimental osteoclast-targeted monoclonal antibody against receptor activator of nuclear factor-kappaB ligand. Two ongoing phase III trials are expected to define its efficacy in preventing bone metastases and disease-related skeletal events in men with prostate cancer. Androgen-deprivation therapy (ADT) for prostate cancer is associated with osteoporosis and fragility fractures. Several bisphosphonates have been shown to improve bone mineral density in men receiving ADT. Two recent phase III trials have shown that denosumab and toremifene reduce the incidence of fragility fractures in these men. The World Health Organization has developed a fracture risk assessment model (FRAX) for the general population to guide the selection of patients who may benefit from pharmacotherapy. In the absence of a prostate cancer-specific algorithm, we advocate the use of FRAX for men receiving ADT.

Immunotherapy of cancer

Major advances have been made in the field of immunology in the past two decades. A better understanding of the molecular and cellular mechanisms controlling the immune system has opened the door to many innovative and promising new cancer therapies that manipulate the immune response. For instance, toll-like receptor agonists have been shown to boost immune responses toward tumors. Also, a wide array of cell-based immunotherapies utilizing T cells, NK cells, and dendritic cells have been established. Furthermore, a rapidly expanding repertoire of monoclonal antibodies is being developed to treat tumors, and many of the available antibodies have demonstrated impressive clinical responses. Here, we examine some of these immunotherapeutic approaches currently in use or testing to treat cancer, and we examine available evidence with regards to mechanism and efficacy of these treatments.

Stability and loss of a virus resistance phenotype over time in transgenic mosquitoes harbouring an antiviral effector gene

Transgenic Aedes aegypti were engineered to express a virus-derived, inverted repeat (IR) RNA in the mosquito midgut to trigger RNA interference (RNAi) and generate resistance to dengue virus type 2 (DENV2) in the vector. Here we characterize genotypic and phenotypic stabilities of one line, Carb77, between generations G(9) and G(17). The anti-DENV2 transgene was integrated at a single site within a noncoding region of the mosquito genome. The virus resistance phenotype was strong until G(13) and suppressed replication of different DENV2 genotypes. From G(14)-G(17) the resistance phenotype to DENV2 became weaker and eventually was lost. Although the sequence of the transgene was not mutated, expression of the IR effector RNA was not detected and the Carb77 G(17) mosquitoes lost their ability to silence the DENV2 genome.

Phase II Study of PEND Chemotherapy in Patients with Refractory/Relapsed Hodgkin Lymphoma

High-dose chemotherapy with autologous marrow or stem cell rescue (HDC/ASCT) is an effective strategy in patients with relapsed Hodgkin lymphoma. Various chemotherapy regimens have been used for cytoreduction prior to HDC/ASCT. In this study, our objective was to determine the response rate to PEND in a group of patients with relapsed Hodgkin lymphoma. Nineteen patients with relapsed or primary refractory Hodgkin lymphoma underwent treatment with the PEND regimen and received a median of 2 cycles (1 - 6 cycles). The PEND regimen builds on our prior results with ABDIC and consists of prednisone 40 mg/m2 orally (PO) daily x 5 days; etoposide 50 mg/m2 PO daily x 14 days; mitoxantrone 5 mg/m2/d IV, days 1 and 3; and DTIC 200 mg/m2/d intravenous continuous infusion (CIV) over 24 h, days 1 to 5, via central venous catheter. The treatment was given every 28 days. There were 3 complete responses (16%) and 10 partial responses (53%) yielding a total response rate of 69% (95% C.I. 43%, 87%). Myelosuppression was the predominant toxicity; no deaths were due to toxicity. After achieving maximum response to PEND, 10 eligible patients received a consolidative treatment with HDC/ASCT. All 6 patients who did not respond to PEND died from disease progression whereas 5 of 13 responders were alive after 10 years of follow-up (3 without disease). There were 11 deaths due to disease progression; three from other causes. The initial response to PEND before subsequent ASCT consolidation treatment appears to be associated with survival. All patients who failed to achieve a response have died. We conclude that PEND is an effective treatment strategy in Hodgkin lymphoma patients previously treated with both ABVD and MOPP.

Cutaneous B-cell lymphoma responds to rituximab: A report of five cases and a review of the literature

Optimal treatment of cutaneous B-cell lymphoma (CBCL) is yet to be established. We treated five patients, each with either extensive lesions, severe comorbidities or who refused treatment with radiation therapy, with rituximab given as a single agent for four weekly intravenous infusions of 375 mg/m2. Maintenance therapy, if initiated, was given at 375 mg/m2 once every 2 - 3 months. Objective clinical responses occurred in all five patients. Three patients have ongoing complete clinical remissions with a median follow-up of 17, 19 and 39 months post achievement of complete remission. One patient died at age 87 years from a non-related cause after 5.5 years of complete remission. One patient received local radiotherapy to a solitary cutaneous site of large-cell lymphoma that developed after 3 years in remission from the low-grade CBCL; no recurrences of either grade CBCL have yet occurred. Treatment was well tolerated. Rituximab is safe and effective in treating of CBCL, either primary CBCL or low-grade lymphomas with relapses limited to the skin. Rituximab appears to present an attractive alternative when radiation therapy is contraindicated or unwanted. Additional collaborative studies are needed to assess the role of rituximab in various clinicopathologic presentations of CBCL.

Phase II study of sunitinib in men with advanced prostate cancer

BACKGROUND

This study explored the efficacy and tolerability of sunitinib, an inhibitor of tyrosine kinase receptors, in men with castration-resistant prostate cancer (CRPC).

METHODS

Men with no prior chemotherapy (group A) and men with docetaxel (Taxotere)-resistant prostate cancer (group B) were treated with sunitinib. The primary end point was confirmed 50% prostate-specific antigen (PSA) decline. Secondary end points included objective response rate and safety. Serum-soluble biomarkers were measured.

RESULTS

Seventeen men were enrolled in each group. One confirmed PSA response was observed in each group, and an additional eight men and seven men had stable PSA at week 12 in groups A and B, respectively. Improvements in imaging were observed in the absence of post-treatment PSA declines. Common adverse effects included fatigue, nausea, diarrhea, myelosuppression and transaminase elevation. Significant changes following sunitinib treatment were observed in serum-soluble biomarkers including soluble vascular endothelial growth factor receptor-2, platelet-derived growth factor aa, placental growth factor and leptin.

CONCLUSIONS

Sunitinib monotherapy resulted in few confirmed 50% post-treatment declines in PSA in men with CRPC. Serum markers of angiogenesis confirmed on-target effects of sunitinib. Assessments of radiographic disease status were often discordant with changes in PSA, indicating that alternate end points are important in future trials.

Combining milatuzumab with bortezomib, doxorubicin, or dexamethasone improves responses in multiple myeloma cell lines

PURPOSE

The humanized anti-CD74 monoclonal antibody, milatuzumab, is in clinical evaluation for the therapy of multiple myeloma (MM). The ability of milatuzumab to increase the efficacy of bortezomib, doxorubicin, and dexamethasone was examined in three human CD74+ MM cell lines, CAG, KMS11, KMS12-PE, and one CD74-MM cell line, OPM-2.

EXPERIMENTAL DESIGN

Activity of milatuzumab as a monotherapy and combined with the drugs was evaluated by studying in vitro cytotoxicity, signaling and apoptotic pathways, and in vivo therapeutic activity in severe combined immunodeficient (SCID) mouse models of MM.

RESULTS

Given as a monotherapy, cross-linked milatuzumab, but not milatuzumab alone, yielded significant antiproliferative effects in CD74+ cells. The combination of cross-linked milatuzumab with bortezomib, doxorubicin, or dexamethasone caused more growth inhibition than either cross-linked milatuzumab or drug alone, producing significant reductions in the IC(50) of the drugs when combined. Efficacy of combined treatments was accompanied by increased levels of apoptosis measured by increases of activated caspase-3 and hypodiploid DNA. Both milatuzumab and bortezomib affect the nuclear factor-kappaB pathway in CAG MM cells. In CAG- or KMS11-SCID xenograft models of disseminated MM, milatuzumab more than doubled median survival time, compared with up to a 33% increase in median survival with bortezomib but no significant benefit with doxorubicin. Moreover, combining milatuzumab and bortezomib increased survival significantly compared with either treatment alone.

CONCLUSIONS

The therapeutic efficacies of bortezomib, doxorubicin, and dexamethasone are enhanced in MM cell lines when given in combination with milatuzumab, suggesting testing these combinations clinically.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

All-sky LIGO search for periodic gravitational waves in the early fifth-science-run data

We report on an all-sky search with the LIGO detectors for periodic gravitational waves in the frequency range 50-1100 Hz and with the frequency's time derivative in the range -5 x 10{-9}-0 Hz s{-1}. Data from the first eight months of the fifth LIGO science run (S5) have been used in this search, which is based on a semicoherent method (PowerFlux) of summing strain power. Observing no evidence of periodic gravitational radiation, we report 95% confidence-level upper limits on radiation emitted by any unknown isolated rotating neutron stars within the search range. Strain limits below 10{-24} are obtained over a 200-Hz band, and the sensitivity improvement over previous searches increases the spatial volume sampled by an average factor of about 100 over the entire search band. For a neutron star with nominal equatorial ellipticity of 10{-6}, the search is sensitive to distances as great as 500 pc.

Search for gravitational-wave bursts from soft gamma repeaters

We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.

Bortezomib sensitizes non-Hodgkin's lymphoma cells to apoptosis induced by antibodies to tumor necrosis factor related apoptosis-inducing ligand (TRAIL) receptors TRAIL-R1 and TRAIL-R2

Non-Hodgkin's lymphoma (NHL) is an increasingly common disease that, despite advances in antibody-targeted therapy, still requires novel therapeutic approaches. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) activates a major nonmitochondrial pathway for tumor cell killing through binding to a receptor family, some activating and some decoy. Agonistic antibodies to the receptors TRAIL-R1 and TRAIL-R2 can mimic many of the effects of TRAIL. We are investigating the effects of such agonistic antibodies, mapatumumab directed at TRAIL-R1 and lexatumumab directed at TRAIL-R2, on NHL cell lines. These antibodies induce apoptosis through caspase-8 but also activate BID to involve the mitochondrial pathway and activate caspase-9. In addition, we find signaling through both the nuclear factor-kappaB and c-Jun NH2-terminal kinase pathways. Because the proteasome inhibitor bortezomib also affects these pathways, we have investigated the combination of TRAIL-R antibodies and bortezomib and show enhanced apoptosis and signaling as well as enhanced killing of NHL cells in a severe combined immunodeficient mouse/human NHL cell line xenograft system. The combination of bortezomib and TRAIL signaling warrants further investigation as a therapeutic regimen. Understanding the multiple intracellular pathways of TRAIL activation may lead to rationally designed therapeutic trials.

Aberrant Huntingtin interacting protein 1 in lymphoid malignancies

Huntingtin interacting protein 1 (HIP1) is an inositol lipid, clathrin, and actin binding protein that is overexpressed in a variety of epithelial malignancies. Here, we report for the first time that HIP1 is elevated in non-Hodgkin's and Hodgkin's lymphomas and that patients with lymphoid malignancies frequently had anti-HIP1 antibodies in their serum. Moreover, p53-deficient mice with B-cell lymphomas were 13 times more likely to have anti-HIP1 antibodies in their serum than control mice. Furthermore, transgenic overexpression of HIP1 was associated with the development of lymphoid neoplasms. The HIP1 protein was induced by activation of the nuclear factor-kappaB pathway, which is frequently activated in lymphoid malignancies. These data identify HIP1 as a new marker of lymphoid malignancies that contributes to the transformation of lymphoid cells in vivo.

Toremifene increases bone mineral density in men receiving androgen deprivation therapy for prostate cancer: interim analysis of a multicenter phase 3 clinical study

PURPOSE

We evaluated the effects of toremifene on bone mineral density, a surrogate for fracture risk, in men receiving androgen deprivation therapy for prostate cancer.

MATERIALS AND METHODS

In an ongoing, multicenter, phase 3 fracture prevention study 1,392 men 50 years or older with prostate cancer receiving androgen deprivation therapy were randomized to 80 mg toremifene per day or placebo. Bone mineral density of the lumbar spine, total hip and femoral neck was assessed using dual energy x-ray absorptiometry. In this planned interim analysis of the first 197 subjects we compared bone mineral density changes from baseline to month 12 between the placebo and toremifene groups.

RESULTS

Compared with the placebo group men in the toremifene group had significant increases in bone mineral density at each evaluated skeletal site. Lumbar spine bone mineral density decreased 0.7% in the placebo group and increased 1.6% in the toremifene group (between group comparison p <0.001). Total hip bone mineral density decreased 1.3% in the placebo group and increased 0.7% in the toremifene group (p = 0.001). Femoral neck bone mineral density decreased 1.3% in the placebo group and increased 0.2% in the toremifene group (p = 0.009). Between group differences in the change in bone mineral density from baseline to month 12 were 2.3%, 2.0% and 1.5% for the lumbar spine, total hip and femoral neck, respectively.

CONCLUSIONS

Toremifene significantly increased hip and spine bone mineral density in men receiving androgen deprivation therapy for prostate cancer. The effect of toremifene on the fracture risk is being assessed in the ongoing randomized, controlled trial.

The application of Efron's bootstrap methods in validating feature classification using artificial neural networks for the analysis of mammographic masses

Efron's bootstrap resampling method is used to analyze the performance of artificial neural networks (ANNs) in the area of feature classification for the analysis of mammographic masses. The purpose of feature classification in mammography is to discover the salient information that can be used to discriminate benign from malignant masses. The performance of ANNs is typically measured in terms of the area under the receiver operating characteristics (ROC) curve (A/sub z/). Performance uncertainty problems and the generalization problems of ANNs are still the critical issues that impede the further application of ANNs in clinical medicine. It is unreasonable and impractical to justify the performance of one ANN being better than another just by its best A/sub z/ value. Efron's bootstrap methods make it possible to quantitatively analyze the performance of ANNs and anticipate its change tendency with relatively high accuracy. Our experimental results show that the probability model of A/sub z/ is close to a normal distribution. The performance of ANNs is more sensitive to the change of topology than that of the size and the composition of the training set. Bootstrap methods can be used to find the optimal epochs and avoid overfitting.

Partial volume effect in quantitative magnetic resonance perfusion imaging

In dynamic-susceptibility contrast (DSC) magnetic resonance (MR) perfusion imaging, the cerebral blood flow (CBF) is estimated from the tissue residue function obtained through deconvolution of the contrast concentration functions. However, the reliability of CBF estimates obtained by deconvolution is sensitive to various distortions. Among the most prominent experimental limitations is the image spatial resolution, leading to partial volume effect (PVE), which arises when the size of the voxel exceeds the volume containing the arterial input signal. PVE results in distortion of the arterial input function (AIF), and directly leads to miscalculation of the CBF. This work demonstrates the degree of the CBF estimation bias that could develop as a result of PVE.

Multiple myeloma. Clinical practice guidelines in oncology

Multiple myeloma will account for an estimated 16,570 new cancer cases in the United States in 2006, with an estimated 11,310 deaths. It is not currently considered curable; however, treatment has evolved rapidly because of new drugs such as bortezomib, thalidomide, and lenalidomide. In addition, increased understanding of the bone marrow microenvironment is creating rationale for new combinations and new drug development. Important updates in the 2007 NCCN guidelines include new recommended single-agent and combination regimens for consideration for induction and salvage therapy.

For the most recent version of the guidelines, please visit NCCN.org

Applying the transient error reconstruction algorithm in the assessment of the cerebral blood flow

The brain perfusion level, characterized by the cerebral blood flow (CBF) parameter, is a known indicator of blood supply in cerebral ischemic stroke. In magnetic resonance dynamic susceptibility contrast (DSC) perfusion studies the CBF parameter is estimated from the residue function obtained from deconvolving the tissue concentration curve by the arterial concentration curve. Deconvolution is a noise sensitive process and ensuring algorithmic stability leads to CBF biases. Distortions are introduced by noise reducing techniques in both the time-domain singular value decomposition (SVD) and frequency-domain based Fourier transform (FT) deconvolution approaches. We provide preliminary results of using the transient error reconstruction algorithm (TERA), an auto regressive moving average based technique, to compensate for these distortions. TERA is applied to determine the characteristics of the low-noise low frequency components of the residue function and then used to reconstruct the time-domain residue function. Results using noise-free signals indicate that the CBF estimates determined using TERA were less sensitive to the tissue mean transit time (MTT) than the time-domain SVD techniques. The difficulties encountered when applying TERA approach to signals with noise levels commonly found in MR perfusion studies are also discussed.

Phase I Study of Bryostatin 1 and Fludarabine in Patients with Chronic Lymphocytic Leukemia and Indolent (Non-Hodgkin's) Lymphoma

PURPOSE

Preclinical studies suggested that bryostatin 1 might potentiate the therapeutic effects of fludarabine in the treatment of hematologic malignancies. We undertook a phase I study to identify appropriate schedules and doses of bryostatin 1 and fludarabine to be used in phase II studies.

EXPERIMENTAL DESIGN

Patients with chronic lymphocytic leukemia (CLL) or indolent lymphoma received fludarabine daily for 5 days and a single dose of bryostatin 1 via a 24-hour continuous infusion either before or after the fludarabine course. Doses were escalated in successive patients until recommended phase II doses for each sequence were identified on the basis of dose-limiting toxic events.

RESULTS

Bryostatin 1 can be administered safely and tolerably with full dose fludarabine (25 mg/m(2)/d x 5). The recommended bryostatin 1 phase II dose is 50 microg/m(2) for both sequences, bryostatin 1 --> fludarabine and fludarabine --> bryostatin 1. The combination is active against both CLL and indolent lymphomas with responses seen in patients who had been previously treated with fludarabine. Correlative studies do not support the hypothesis that bryostatin 1 potentiates fludarabine activity through down-regulation of protein kinase C in target cells.

CONCLUSIONS

Bryostatin 1 can be administered with full dose fludarabine, and the combination is moderately active in patients with persistent disease following prior treatment. In view of the activity of monoclonal antibodies such as the anti-CD20 monoclonal antibody rituximab in the treatment of CLL and indolent lymphomas, the concept of combining bryostatin 1 and fludarabine with rituximab warrants future consideration.

Phase II trial of idiotype vaccination in previously treated patients with indolent non-Hodgkin's lymphoma resulting in durable clinical responses

PURPOSE

To evaluate idiotype (Id) vaccination as a single agent in previously treated patients with indolent non-Hodgkin's lymphoma.

PATIENTS AND METHODS

Patients underwent biopsy for determination of their lymphoma-specific Id sequence. Recombinant Id protein was manufactured and covalently linked with keyhole limpet hemocyanin (KLH) to generate Id/KLH. Patients received Id/KLH 1 mg on day 1 subcutaneously, with granulocyte-macrophage colony-stimulating factor 250 mug on days 1 to 4, monthly for 6 months. Booster injections were administered until progression. Both clinical and immune responses were evaluated.

RESULTS

Thirty-two previously treated patients received at least one injection of Id/KLH, and 31 were assessed for efficacy. Responses were observed in four patients (one complete response and three partial responses). Median time to onset of response was 5.9 months (range, 2.3 to 14.1 months). Median duration of response has not been reached but should be at least 19.4 months (range, 10.4 to 27.2+ months). Median time to progression is 13.5 months. The most common adverse events were mild to moderate injection site reactions. Six (67%) of nine patients tested demonstrated a cellular immune response, and four (20%) of 20 patients demonstrated an antibody response against their Id.

CONCLUSION

This trial demonstrates that Id/KLH alone can induce tumor regression and durable objective responses. Further study of Id/KLH is recommended in other settings where efficacy may be further enhanced as in first-line therapy or after cytoreductive therapy.

Non-Hodgkin's lymphoma. Clinical practice guidelines in oncology

Non-Hodgkin's lymphomas (NHLs) may be classified on the basis of morphology, natural history, and immunophenotypic and molecular characteristics. These guidelines were developed for more common NHL histologic types, including chronic lymphocytic leukemia/small lymphocytic lymphoma, follicular lymphoma, and diffuse large B-cell lymphoma, and for less common entities with unique natural histories and therapies, such as marginal zone lymphoma, mantle cell lymphoma, and highly aggressive lymphoma subtypes, including Burkitt's, and lymphoblastic lymphomas and AIDS-related B-cell lymphomas. Certain components of the diagnosis and therapy of the various NHLs are similar. In all cases, an accurate pathologic diagnosis must first be made.

For the most recent version of the guidelines, please visit NCCN.org

Regulation of Osteoblast Gene Expression and Phenotype by Polylactide-fatty Acid Surfaces

Cell function is influenced by surface structure and molecules. Molecules that enhance cellular differentiation can be applied to tissue scaffold surfaces to stimulate endogenous tissue regeneration. The application of this approach to bone implants yields surfaces coated with factors (proteins, peptides, etc...) that promote the differentiation of osteoblasts, the cells that make bone. Increased bone formation leads to increased healing and union of the implant with endogenous bone. To obtain better control over surface coating we developed PLLA copolymers with allyl (PLLA-co-DAG) and 3-hydroxypropyl (PLLA-co-HP) side chains to which we can attach functional groups. Given the potential of fatty acids being able to incorporate into lipid bilayers and/or influence gene expression, we grafted different fatty acid side chains to PLLA-co-HP by esterifying the corresponding fatty acids with the PLLA-co-HP 3-hydroxypropyl side chains. The effects of the polymer modifications on osteoblasts were then evaluated. While cellular morphology differed between surface coatings, they did not reflect changes in cellular phenotype. Changes in gene expression were most evident with arachidonate and 3-hydroxypropyl side-chains which exhibited osteoblast differentiating capabilities. Linoleate, myristate, oleate, and stearate ester side-chains did not have a significant influence on osteoblast phenotype. Growth characteristics of osteoblasts did not differ between the fatty acid copolymer films, although cells grown on PLLA-co-HP exhibited a trend toward increased growth. Taken together our findings demonstrate that surface fatty acid composition can impact osteoblast phenotype.

Is correction necessary when clinically determining quantitative cerebral perfusion parameters from multi-slice dynamic susceptibility contrast MR studies?

Several groups have modified the standard singular value decomposition (SVD) algorithm to produce delay-insensitive cerebral blood flow (CBF) estimates from dynamic susceptibility contrast (DSC) perfusion studies. However, new dependences of CBF estimates on bolus arrival times and slice position in multi-slice studies have been recently recognized. These conflicting findings can be reconciled by accounting for several experimental and algorithmic factors. Using simulation and clinical studies, the non-simultaneous measurement of arterial and tissue concentration curves (relative slice position) in a multi-slice study is shown to affect time-related perfusion parameters, e.g. arterial-tissue-delay measurements. However, the current clinical impact of relative slice position on amplitude-related perfusion parameters, e.g. CBF, can be expected to be small unless any of the following conditions are present individually or in combination: (a) high concentration curve signal-to-noise ratios, (b) small tissue mean transit times, (c) narrow arterial input functions or (d) low temporal resolution of the DSC image sequence. Recent improvements in magnetic resonance (MR) technology can easily be expected to lead to scenarios where these effects become increasingly important sources of inaccuracy for all perfusion parameter estimates. We show that using Fourier interpolated (high temporal resolution) residue functions reduces the systematic error of the perfusion parameters obtained from multi-slice studies.

Pure red cell aplasia in B-cell lymphoproliferative disorder treated with rituximab: Report of two cases and review of the literature

Pure red cell aplasia (PRCA) is an unusual cause of anemia in patients with chronic lymphoproliferative disorders. Here, we present two cases of PRCA, one associated with chronic lymphocytic leukemia (CLL) and the other with splenic marginal zone lymphoma, in which the PRCA responded dramatically to treatment with rituximab. We then review the literature on PRCA in lymphoma and response to rituximab. PRCA associated with CLL or lymphoma may be another indication for rituximab therapy.

Upper limits on a stochastic background of gravitational waves

The Laser Interferometer Gravitational-Wave Observatory has performed a third science run with much improved sensitivities of all three interferometers. We present an analysis of approximately 200 hours of data acquired during this run, used to search for a stochastic background of gravitational radiation. We place upper bounds on the energy density stored as gravitational radiation for three different spectral power laws. For the flat spectrum, our limit of omega0 < 8.4 x 10(-4) in the 69-156 Hz band is approximately 10(5) times lower than the previous result in this frequency range.

Enhanced efficacy of gemcitabine in combination with anti-CD20 monoclonal antibody against CD20+ non-Hodgkin's lymphoma cell lines in vitro and in scid mice

Background

Despite exciting new targeted therapeutics against non-Hodgkin's lymphoma (NHL), chemotherapy remains a cornerstone of therapy. While purine nucleoside analogs have significant activity in low grade NHL, the pyrimidine nucleoside analog gemcitabine has been less extensively studied, but has important activity. Use of the anti-CD20 monoclonal antibody rituximab in combination with chemotherapy for B-NHL is becoming prevalent in clinical practice, but has not been extensively studied in pre-clinical models.

Methods

We have tested the activity of gemcitabine ± rituximab in vitro and in scid/human NHL xenograft models. We used two t(14;18)+, CD20+ follicular B cell NHL cell lines, DoHH2 a transformed NHL line and WSU-FSCCL isolated from pleural fluid of a patient with indolent NHL.

Results

Gemcitabine is cytotoxic to DoHH2 and WSU-FSCCL cells in vitro, and the IC₅₀ is 2–3 fold lower in the presence of rituximab. Apoptosis is also enhanced in the presence of rituximab. Clearance of NHL cells from ascites in scid mice is prolonged by the combination, as compared with either agent alone. Most importantly, survival of scid mice bearing human NHL cells is significantly prolonged by the combination of gemcitabine + rituximab.

Conclusion

Based on our pre-clinical data showing prolonged survival of mice bearing human lymphoma cell line xenografts after treatment with gemcitabine + anti-CD20 antibody, this combination, expected to have non-overlapping toxicity profiles, should be explored in clinical trials.

Limits on gravitational-wave emission from selected pulsars using LIGO data

We place direct upper limits on the amplitude of gravitational waves from 28 isolated radio pulsars by a coherent multidetector analysis of the data collected during the second science run of the LIGO interferometric detectors. These are the first direct upper limits for 26 of the 28 pulsars. We use coordinated radio observations for the first time to build radio-guided phase templates for the expected gravitational-wave signals. The unprecedented sensitivity of the detectors allows us to set strain upper limits as low as a few times 10(-24). These strain limits translate into limits on the equatorial ellipticities of the pulsars, which are smaller than 10(-5) for the four closest pulsars.