Purpose

A phase I/II study of cixutumumab (IMC-A12) in children with refractory solid tumors was conducted. This study was designed to assess the toxicities, pharmacokinetics, and pharmacodynamics of cixutumumab in children to determine a recommended phase II dose and to assess antitumor activity in Ewing sarcoma (ES).

Patients and Methods

Pediatric patients with relapsed or refractory solid tumors were treated with cixutumumab as a 1-hour intravenous infusion once per week. Two dose levels—6 and 9 mg/kg—were evaluated using a standard three-plus-three cohort design. Patients with refractory ES were treated in an expanded phase II cohort at each dose level.

Results

Forty-seven eligible patients with a median age of 15 years (range, 4 to 28 years) were enrolled. Twelve patients were treated in the dose-finding phase. Hematologic and nonhematologic toxicities were generally mild and infrequent. Dose-limiting toxicities included grade 4 thrombocytopenia at 6 mg/kg and grade 3 dehydration at 9 mg/kg. Mean trough concentration (± standard deviation) at 9 mg/kg was 106 ± 57 μg/mL, which exceeded the effective trough concentration of 60 μg/mL observed in xenograft models. Three patients with ES had confirmed partial responses: one of 10 at 6 mg/kg and two of 20 at 9 mg/kg. Serum insulin-like growth factor I (IGF-I) levels consistently increased after one dose of cixutumumab. Tumor IGF-I receptor expression by immunohistochemistry did not correlate with response in patients with ES.

Conclusion

Cixutumumab is well tolerated in children with refractory solid tumors. The recommended phase II dose is 9 mg/kg. Limited single-agent activity of cixutumumab was seen in ES.

Background

The second generation antipsychotic (SGA) drugs are widely used in psychiatry due to their clinical efficacy and low incidence of neurological side-effects. However, many drugs in this class cause deleterious metabolic side-effects. Animal models accurately predict metabolic side-effects for SGAs with known clinical metabolic liability. We therefore used preclinical models to evaluate the metabolic side-effects of glucose intolerance and insulin resistance with the novel SGAs asenapine and iloperidone for the first time. Olanzapine was used as a comparator.

Methods

Adults female rats were treated with asenapine (0.01, 0.05, 0.1, 0.5, 1.0 mg/kg), iloperidone (0.03, 0.5, 1.0, 5.0, 10.0 mg/kg) or olanzapine (0.1, 0.5, 1.5, 5.0, 10.0 mg/kg) and subjected to the glucose tolerance test (GTT). Separate groups of rats were treated with asenapine (0.1 and 1.0 mg/kg), iloperidone (1.0 and 10 mg/kg) or olanzapine (1.5 and 15 mg/kg) and tested for insulin resistance with the hyperinsulinemic-euglycemic clamp (HIEC).

Results

Asenapine showed no metabolic effects at any dose in either test. Iloperidone caused large and significant glucose intolerance with the three highest doses in the GTT, and insulin resistance with both doses in the HIEC. Olanzapine caused significant glucose intolerance with the three highest doses in the GTT, and insulin resistance with the higher dose in the HIEC.

Conclusions

In preclinical models, asenapine shows negligible metabolic liability. By contrast, iloperidone exhibits substantial metabolic liability, comparable to olanzapine. These results emphasize the need for appropriate metabolic testing in patients treated with novel SGAs where current clinical data do not exist.

Development of a vaccine for HIV-1 requires a detailed understanding of the neutralizing antibody responses that can be experimentally elicited to difficult-to-neutralize primary isolates. Rabbits were immunized with the gp120 subunit of HIV-1 JR-CSF envelope (Env) using a DNA-prime protein-boost regimen. We analyzed five sera that showed potent autologous neutralizing activity (IC50s at ∼103 to 104 serum dilution) against pseudoviruses containing Env from the primary isolate JR-CSF but not from the related isolate JR-FL. Pseudoviruses were created by exchanging each variable and constant domain of JR-CSF gp120 with that of JR-FL or with mutations in putative N-glycosylation sites. The sera contained different neutralizing activities dependent on C3 and V5, C3 and V4, or V4 regions located on the glycan-rich outer domain of gp120. All sera showed enhanced neutralizing activity toward an Env variant that lacked a glycosylation site in V4. The JR-CSF gp120 epitopes recognized by the sera are generally distinct from those of several well characterized mAbs (targeting conserved sites on Env) or other type-specific responses (targeting V1, V2, or V3 variable regions). The activity of one serum requires specific glycans that are also important for 2G12 neutralization and this serum blocked the binding of 2G12 to gp120. Our findings show that different fine specificities can achieve potent neutralization of HIV-1, yet this strong activity does not result in improved breadth.

This study examined fMRI activation when perceivers either passively observed or observed and imitated matched or mismatched audiovisual (“McGurk”) speech stimuli. Greater activation was observed in the inferior frontal gyrus (IFG) overall for imitation than for perception of audiovisual speech and for imitation of the McGurk-type mismatched stimuli than matched audiovisual stimuli. This unique activation in the IFG during imitation of incongruent audiovisual speech may reflect activation associated with direct matching of incongruent auditory and visual stimuli or conflict between category responses. This study provides novel data about the underlying neurobiology of imitation and integration of AV speech.

Background

The second-generation antipsychotic drug olanzapine is an effective pharmacological treatment for psychosis. However, use of the drug is commonly associated with a range of metabolic side effects, including glucose intolerance and insulin resistance. These symptoms have been accurately modelled in rodents.

Methods

We compared the effects of 3 distinct classes of antidiabetic drugs, metformin (100 and 500 mg/kg, oral), rosiglitazone (6 and 30 mg/kg, oral) and glyburide (2 and 10 mg/kg, oral), on olanzapine-induced metabolic dysregulation. After acutely treating female rats with lower (7.5 mg/kg) or higher (15 mg/kg) doses of olanzapine, we assessed glucose intolerance using the glucose tolerance test and measured insulin resistance using the homeostatic model assessment of insulin resistance equation.

Results

Both doses of olanzapine caused pronounced glucose dysregulation and insulin resistance, which were significantly reduced by treatment with metformin and rosiglitazone; however, glucose tolerance did not fully return to control levels. In contrast, glyburide failed to reverse the glucose intolerance caused by olanzapine despite increasing insulin levels.

Limitations

We evaluated a single antipsychotic drug, and it is unknown whether other antipsychotic drugs are similarly affected by antidiabetic treatments.

Conclusion

The present study indicates that oral hypoglycemic drugs that influence hepatic glucose metabolism, such as metformin and rosiglitazone, are more effective in regulating olanzapine-induced glucose dysregulation than drugs primarily affecting insulin release, such as glyburide. The current model may be used to better understand the biological basis of glucose dysregulation caused by olanzapine and how it can be reversed.

Background

The purpose of this study was to determine whether adding the anti-epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib to carboplatin/paclitaxel improved pathologic complete response (pCR) at reassessment surgery in epithelial ovarian, fallopian tube, or primary peritoneal cancers (OFPC).

Methods

Patients with stage III-IV OFPC initiated treatment within 12 weeks of initial cytoreductive surgery or, after histologic confirmation of diagnosis, neoadjuvantly. Treatment included paclitaxel (175 mg/m2) and carboplatin (AUC 6) every 3 weeks for up to 6 cycles, plus oral erlotinib 150 mg daily. The primary objective was to determine whether the pCR rate at reassessment surgery was at least 60% after optimal cytoreduction at initial surgery (< 1 cm residual disease), or at least 40% after suboptimal cytoreduction (at least 1 cm residual disease) using a two-stage design (alpha = 0.10, beta =0.10).

Results

The study population included 56 patients with stage III-IV OFPC. EGFR gene amplification was present in 15% of the 20 tumors evaluated. Twenty-eight patients had protocol therapy after optimal cytoreduction (stratum I), 23 had protocol therapy either after suboptimal cytoreduction (stratum II), and 5 received neoadjuvant therapy prior to cytoreduction (stratum III). Pathologic CR was confirmed in 8 patients (29%; 95% confidence intervals 13%, 49%) in stratum I and 3 patients (11%, 95% C.I. 2%, 28%) in stratum II, which did not meet the prespecified efficacy endpoint in either stratum.

Conclusions

Among unselected patients, erlotinib plus carboplatin-paclitaxel is not more effective than historical experience with carboplatin-paclitaxel alone in patients with stage III-IV OFPC.

Purpose

Mammalian target of rapamycin (mTOR) inhibitors mediate AKT activation through a type 1 insulin-like growth factor receptor (IGF-1R)-dependent mechanism. Combining the mTOR inhibitor temsirolimus with cixutumumab, a fully human IgG1 monoclonal antibody directed against IGF-1R, was expected to enhance mTOR-targeted anticancer activity by modulating resistance to mTOR inhibition. Objectives of this Phase I study were to evaluate the tolerability and activity of temsirolimus and cixutumumab.

Experimental Design

Patients in sequential cohorts (“3+3” design) received escalating doses of temsirolimus with cixutumumab weekly for 28 days. At MTD, 21 patients were randomized into three separate drug sequence treatment groups for serial blood draws and FDG-PET/CT scans for pharmacodynamic analyses (PD).

Results

Forty-two patients with advanced cancer (19M/23F, median age = 53, median number of prior therapies = 4) were enrolled. MTD was reached at cixutumumab, 6 mg/kg IV and temsirolimus, 25 mg IV. DLTs included Grade 3 mucositis, febrile neutropenia, and Grade 4 thrombocytopenia. Most frequent toxicities were hypercholesterolemia, hypertriglyceridemia, hyperglycemia, thrombocytopenia, and mucositis. Tumor reduction was observed in 2 of 3 patients with Ewing's sarcoma and in 4 of 10 patients with adrenocortical carcinoma. PD data suggest that cixutumumab alone or combined with temsirolimus increased plasma IGF-1 and IGFBP3. FDG-PET/CT showed the odds of achieving stable disease decreased by 58% (P =0.1213) with a one-unit increase in absolute change of SUV from baseline to Day 3.

Conclusions

Temsirolimus combined with cixutumumab was well tolerated. We are currently enrolling expansion cohorts at the MTD for Ewing's sarcoma and adrenocortical carcinoma.

Background

Drug use and sex work have had facilitative roles in the transmission of HIV/AIDS in China. Stopping drug use among sex workers may help to control the growth of the HIV/AIDS epidemic among Chinese sex workers.

Methods

From March 2006 to November 2009, female sex workers (FSW) in Kaiyuan City, Yunnan, China were recruited into an open cohort study. Participants were interviewed and tested for drug use and HIV/sexually transmitted infection (STI) prevalence. Follow-up surveys were conducted every six months. Multivariate Cox proportional hazards regression model with time dependent variables was used to measure the associations between independent variables and drug initiation.

Results

During the course of the study, 66 (8.8%) FSWs initiated drug use yielding an overall incidence of 6.0 per 100 person years (PY) (95% confidence interval [CI], 4.67–7.58). In the multivariate Cox proportional hazards regression model, being HIV-positive and aware of positive serostatus (adjusted hazard ratio [AHR] 2.6, 95% CI 1.24–5.55), age at initiation of commercial sex work <20 years (AHR 1.8, 95% CI 1.12–3.01), and working in a high-risk establishment (AHR 1.9, 95% CI 1.14–3.04) were associated with illicit drug initiation.

Conclusions

Being HIV-positive and aware of positive serostatus was the most salient predictor for the initiation of illicit drug use. Interventions offering sources of education, treatment, support, and counseling to HIV-positive FSWs need to be implemented in order to help promote self-efficacy and safe behaviors among this group of high-risk women.

Bevacizumab is a humanized recombinant monoclonal antibody that neutralizes vascular endothelial growth factor, an agent with pro-angiogenic effects in melanoma. Interferon-alpha (IFN-α) has anti-angiogenic properties via its ability to down-regulate basic-fibroblast growth factor levels. We hypothesized that the co-administration of these agents would lead to tumor regression. Patients with metastatic melanoma received bevacizumab 15 mg/kg iv on day 1 of the 2 week cycle. IFN-α was administered thrice weekly at 5 MU/m2 sc during cycle 1 and was increased to 10 MU/m2 during cycle 2. Patients were restaged every 6 cycles. Patients with stable disease or a response continued with therapy. Baseline serum VEGF and FGF were measured. Twenty-five patients were accrued. Mean age was 58.4 years. Eleven patients required IFN-α dose reductions due to toxicity. Common grade 3 toxicities associated with IFN-α included fatigue and myalgia. Bevacizumab administration was associated with grade 2–3 proteinuria in 6 patients. Grade 4 adverse events were pulmonary embolus (1), myocardial infarction (1), and stroke (1). Six patients had a partial response, and five patients exhibited stable disease that lasted greater than 24 weeks (range 30–122 weeks). Median PFS and OS were 4.8 months and 17 months, respectively. Significantly lower FGF levels were observed in patients with a partial response compared to those with stable or progressive disease (p=0.040). Administration of bevacizumab with IFN led to a clinical response in 24% of patients with stage IV melanoma and stabilization of disease in another 20% of patients. This regimen has activity in advanced melanoma.

Background & Aims

Direct germline analysis could be used to screen high-risk patients for DNA mismatch repair gene mutations associated with Lynch Syndrome. To further evaluate this potential strategy, we examined the prevalence of MLH1, MSH2 and MSH6 mutations in a population-based sample of young-onset (age < 50 years) CRC cases.

Methods

Young-onset CRC cases were randomly selected from three Colon Cancer Family Registry sites (Cancer Care Ontario, Mayo Clinic, University of Southern California). Extracted DNA from peripheral blood leukocytes was shipped to Myriad Genetic Laboratories (Salt Lake City, UT) for MLH1, MSH2 and MSH6 sequencing, and duplication/deletion analyses for MLH1 and MSH2. Results were reported as: deleterious/suspected deleterious, likely neutral, variant of uncertain significance, or no alteration detected. Germline data were compared to Amsterdam II criteria (ACII) and immunohistochemistry testing (IHC) in secondary analyses.

Results

In 195 subjects, 11 had deleterious/suspected deleterious mutations (5.6%; 95% CI, 2.8%–9.9%), 12 had likely neutral alterations (6.2%; 3.2%–10.5%), 14 had variants of uncertain significance (7.2%; 4.0%–11.8%), 2 had both a likely neutral alteration and a variant of uncertain significance (1.0%; 0.1%–3.7%) and 156 had no alteration detected (80.0%; 73.7%–85.4%). Sensitivity, specificity, positive and negative predictive values for detecting deleterious/suspected deleterious mutations by ACII were 36.4% (4/11), 96.7% (178/184), 40.0% (4/10), and 96.2% (178/185) and by IHC testing were 85.7% (6/7), 91.9% (136/148), 33.3% (6/18) and 99.3% (136/137).

Conclusion

In this population-based sample of young-onset CRC cases, germline MLH1, MSH2 and/or MSH6 mutations were more prevalent than previously reported for CRC patients overall. Yet, since only about 1 in 20 young-onset CRC cases had confirmed deleterious/suspected deleterious mutations, further comparative effectiveness research is needed to determine the preferred Lynch Syndrome screening strategy for this high-risk group.

PURPOSE

Inhibition of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF) pathways may result in synergistic antitumour activity. We designed a phase I study to evaluate the combination of vandetanib, an investigational agent with activity against EGF receptor and VEGF receptor 2, and bevacizumab, a monoclonal antibody against VEGF.

EXPERIMENTAL DESIGN

Patients with advanced solid tumours and lymphomas were enrolled. Objectives were to determine the safety and maximum tolerated dose of the combination, characterise pharmacokinetics, measure angiogenic marker changes in blood, and assess tumour blood flow using dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). Vandetanib was given orally once daily and bevacizumab intravenously once every 3 weeks in 21-day cycles utilizing a standard dose escalation design.

RESULTS

Fifteen patients were enrolled, and a total of 94 cycles of therapy were administered. No protocol-defined dose-limiting toxicities were observed; due to toxicities associated with chronic dosing, hypertension, proteinuria, diarrhea, and anorexia, dose escalation was stopped at the second dose level. We observed one partial response and one minor response; nine patients experienced stable disease. There were significant changes in plasma VEGF and placental-derived growth factor levels, and decreases in Ktrans and kep were observed by DCE-MRI.

CONCLUSION

In this trial, we safely combined two targeted agents that cause dual blockade of the VEGF pathway, demonstrated preliminary evidence of clinical activity, and conducted correlative studies demonstrating anti-angiogenic effect. The recommended phase II dose was established as vandetanib 200 mg daily and bevacizumab 7.5 mg/kg every 3 weeks.

Background

Recent studies have shown that human copper transporter 1 (hCtr1), the major copper influx transporter, is involved in the transport of platinum-based antitumor agents. We investigated the predictive and prognostic values of hCtr1, and cooper efflux transporters ATP7A and ATP7B, in patients with locally advanced non-small cell lung cancer (NSCLC) receiving first-line platinum-based chemotherapy.

Methods

From 2004 to 2009, we identified 54 consecutive stage III NSCLC patients who underwent first-line platinum-based doublet chemotherapy. Immunohistochemical studies of hCtr1, ATP7A and ATP7B on the paraffin-embedded pre-treatment tumor samples were performed and correlated with chemotherapy response and survival.

Results

Overexpression of hCtr1, ATP7A and ATP7B were observed in 68%, 48% and 74% of the participants, respectively. hCtr1 overexpression was associated with better chemotherapy responses (P < 0.01); whereas ATP7A and ATP7B were not. Patients with hCtr1 overexpressing tumors had better progression-free survival (PFS) and overall survival (OS) (P = 0.01 and 0.047, respectively). In multivariate analyses for chemotherapy response and PFS, only hCtr1 overexpression emerged as a favorable independent predictive and prognostic factor (all P < 0.01).

Conclusion

This is the first report to state that hCtr1 is not only an independent predictor of platinum-based chemotherapy response but also a prognostic factor in stage III NSCLC.

Several studies have demonstrated that as listeners hear sentences describing events in a scene, their eye movements anticipate upcoming linguistic items predicted by the unfolding relationship between scene and sentence. While this may reflect active prediction based on structural or contextual expectations, the influence of local thematic priming between words has not been fully examined. In Experiment 1, we presented verbs (e.g., arrest) in active (Subject-Verb-Object) sentences with displays containing verb-related patients (e.g., crook) and agents (e.g., policeman). We examined patient and agent fixations following the verb, after the agent role had been filled by another entity, but prior to bottom-up specification of the object. Participants were nearly as likely to fixate agents “anticipatorily” as patients, even though the agent role was already filled. However, the slight patient advantage suggested simultaneous influences of both local priming and active prediction. In Experiment 2, using passives (Object-Verb-Subject), we found stronger, but still graded influences of role prediction when more time elapsed between verb and target, and more syntactic cues were available. We interpret anticipatory fixations as emerging from constraint-based processes that involve both non-predictive thematic priming and active prediction.

Biomaterials interface with toll-like receptor (TLR) 9-mediated innate immunity in a wide range of medical applications, such as tissue implants and drug delivery systems. The stimulation of TLR9 can lead to two different signaling pathways, resulting in the generation of proinflammatory cytokines (i.e. IL-6) and/or type I interferons (IFNs, i.e. IFN-α). These two categories of cytokines differentially influence both innate and adaptive immunity. Although particle size is known to be a critical parameter of biomaterials, its role in TLR9-mediated cytokine profiles is not clear. Here, we examined how the size of biomaterials impacted cytokine profiles by using polystyrene particles of defined sizes as model carriers for TLR9 agonists (CpG oligonucleotides (CpG ODNs)). CpG ODNs bound to nano- to submicro- particles stimulated the production of both IL-6 and IFN-α, while those bound to microparticles resulted in IL-6 secretions only. The differential TLR9-mediated cytokine profiles were attributed to the pH of endosomes that particles trafficked to. The magnitude of IFN-α production was highly sensitive to the change in endosomal pH in comparison to that of IL-6. Our results define two critical design variables, size and the ability to modulate endosomal pH, for the engineering of biomaterials that potentially interface with TLR9-mediated innate immunity. The fine control of these two variables will allow us to fully exploit the beneficial facets of TLR9-mediated innate immunity while minimizing undesirable side effects.

Genetic analysis identifies the HMMR gene as a modifier of the breast cancer risk associated with BRCA1 gene mutation, while cell biological analysis of the protein product suggests a function in regulating development of the mammary gland.

Differentiated mammary epithelium shows apicobasal polarity, and loss of tissue organization is an early hallmark of breast carcinogenesis. In BRCA1 mutation carriers, accumulation of stem and progenitor cells in normal breast tissue and increased risk of developing tumors of basal-like type suggest that BRCA1 regulates stem/progenitor cell proliferation and differentiation. However, the function of BRCA1 in this process and its link to carcinogenesis remain unknown. Here we depict a molecular mechanism involving BRCA1 and RHAMM that regulates apicobasal polarity and, when perturbed, may increase risk of breast cancer. Starting from complementary genetic analyses across families and populations, we identified common genetic variation at the low-penetrance susceptibility HMMR locus (encoding for RHAMM) that modifies breast cancer risk among BRCA1, but probably not BRCA2, mutation carriers: n = 7,584, weighted hazard ratio (wHR) = 1.09 (95% CI 1.02–1.16), ptrend = 0.017; and n = 3,965, wHR = 1.04 (95% CI 0.94–1.16), ptrend = 0.43; respectively. Subsequently, studies of MCF10A apicobasal polarization revealed a central role for BRCA1 and RHAMM, together with AURKA and TPX2, in essential reorganization of microtubules. Mechanistically, reorganization is facilitated by BRCA1 and impaired by AURKA, which is regulated by negative feedback involving RHAMM and TPX2. Taken together, our data provide fundamental insight into apicobasal polarization through BRCA1 function, which may explain the expanded cell subsets and characteristic tumor type accompanying BRCA1 mutation, while also linking this process to sporadic breast cancer through perturbation of HMMR/RHAMM.

Author Summary

Mutations in two genes that were initially identified as predisposing carriers to early-onset breast cancer, BRCA1 and BRCA2, cause similar perturbations in cellular responses to DNA damage but predispose carriers to distinct tumor types. Thus, the two genes may trigger different carcinogenic processes. We have used genetic analyses of affected families to uncover additional genetic variation that is linked to the risk of developing cancer for carriers of BRCA1 mutations. This variation falls within a centrosomal gene, named HMMR. The protein product of HMMR, which is called RHAMM, works in concert with BRCA1 to regulate the structure of normal breast cells as they grow and become polarized. This polarization process depends upon a balance between the activities of BRCA1 and the Aurora kinase A, with the kinase opposing BRCA1 function and promoting growth. Our findings provide new insights into the mechanism through which BRCA1 may promote commitment of initially bipotent mammary cells towards the luminal lineage, and how loss of this function may predispose cells to become breast tumors of a basal-like type.

Background

Milk protein fractions and peptides have been shown to have bioactive properties. This preliminary study examined the potential mechanisms of action and clinical safety of novel milk protein peptide (MP).

Findings

A novel MP mixture inhibits the tyrosine kinase activity of epidermal growth factor receptor (EGFR), vascular endothelial growth factor receptor 2 (VEGFR2), and insulin receptor (IR) with IC50 of 9.85 μM, 7.7 μM, and 6.18 μM respectively. In vitro, this multi-kinase inhibitor causes apoptosis in HT-29 colon cancer cells, and in a C. elegans worm study, showed a weak but significant increase in lifespan. A six week double-blind, placebo-controlled study involving 73 healthy volunteers demonstrated that the MP mixture is safe to consume orally. All clinical blood markers remained within normal levels and no clinically significant side effects were reported. There was some evidence of improved insulin sensitivity, neutrophil-to-lymphocyte ratio (NLR), and quality of life assessment of role of physical function.

Conclusions

These data in combination with the observed in vitro anti-cancer properties warrant further clinical studies to investigate this MP mixture as a potential clinical nutrition intervention for improving the quality of life and clinical outcomes in cancer patients.

Trial Registration

NCT01412658

With prevalence rates of postnatal depression (PND) as high as at least 7%, there was a need for early detection and intervention of postpartum mental illness amongst Singaporean mothers. This is a report on the first year results of our country's first PND Intervention Programme. The programme consists of two phases: (1) postpartum women were screened with the Edinburgh Postnatal Depression Scale and provided appropriate care plans; (2) individualized clinical intervention using a case management multidisciplinary team model. Screening for PND was generally acceptable, as 64% eligible women participated voluntarily. Nine percent (126) were identified as probable cases from 1369 women. Forty-one women accepted intervention and achieved 78% reduction in the EPDS symptom scores to below the cutoff of 13, 76% had improvement in GAF functioning scores, and 68% had improved health quality scores. Preliminary results are promising, and this intervention model can be replicated.

A prophylactic vaccine is needed to slow the spread of HIV-1 infection. Optimization of the wild-type envelope glycoproteins to create immunogens that can elicit effective neutralizing antibodies is a high priority. Starting with ten genes encoding subtype B HIV-1 gp120 envelope glycoproteins and using in vitro homologous DNA recombination, we created chimeric gp120 variants that were screened for their ability to bind neutralizing monoclonal antibodies. Hundreds of variants were identified with novel antigenic phenotypes that exhibit considerable sequence diversity. Immunization of rabbits with these gp120 variants demonstrated that the majority can induce neutralizing antibodies to HIV-1. One novel variant, called ST-008, induced significantly improved neutralizing antibody responses when assayed against a large panel of primary HIV-1 isolates. Further study of various deletion constructs of ST-008 showed that the enhanced immunogenicity results from a combination of effective DNA priming, an enhanced V3-based response, and an improved response to the constant backbone sequences.

BACKGROUND

Preclinical and preliminary clinical data indicate that ch14.18, a monoclonal antibody against the tumor-associated disialoganglioside GD2, has activity against neuroblastoma and that such activity is enhanced when ch14.18 is combined with granulocyte–macrophage colony-stimulating factor (GM-CSF) or interleukin-2. We conducted a study to determine whether adding ch14.18, GM-CSF, and interleukin-2 to standard isotretinoin therapy after intensive multimodal therapy would improve outcomes in high-risk neuroblastoma.

METHODS

Patients with high-risk neuroblastoma who had a response to induction therapy and stem-cell transplantation were randomly assigned, in a 1:1 ratio, to receive standard therapy (six cycles of isotretinoin) or immunotherapy (six cycles of isotretinoin and five concomitant cycles of ch14.18 in combination with alternating GM-CSF and interleukin-2). Event-free survival and overall survival were compared between the immunotherapy group and the standard-therapy group, on an intention-to-treat basis.

RESULTS

A total of 226 eligible patients were randomly assigned to a treatment group. In the immunotherapy group, a total of 52% of patients had pain of grade 3, 4, or 5, and 23% and 25% of patients had capillary leak syndrome and hypersensitivity reactions, respectively. With 61% of the number of expected events observed, the study met the criteria for early stopping owing to efficacy. The median duration of follow-up was 2.1 years. Immunotherapy was superior to standard therapy with regard to rates of event-free survival (66±5% vs. 46±5% at 2 years, P = 0.01) and overall survival (86±4% vs. 75±5% at 2 years, P = 0.02 without adjustment for interim analyses).

CONCLUSIONS

Immunotherapy with ch14.18, GM-CSF, and interleukin-2 was associated with a significantly improved outcome as compared with standard therapy in patients with high-risk neuroblastoma.

Background

Insulin-like growth factor 1 receptor (IGF1R) targeted therapies have resulted in responses in a small number of patients with advanced metastatic Ewing's sarcoma. We performed morphoproteomic profiling to better understand response/resistance mechanisms of Ewing's sarcoma to IGF1R inhibitor-based therapy.

Methodology/Principal Findings

This pilot study assessed two patients with advanced Ewing's sarcoma treated with IGF1R antibody alone followed by combined IGF1R inhibitor plus mammalian target of rapamycin (mTOR) inhibitor treatment once resistance to single-agent IGF1R inhibitor developed. Immunohistochemical probes were applied to detect p-mTOR (Ser2448), p-Akt (Ser473), p-ERK1/2 (Thr202/Tyr204), nestin, and p-STAT3 (Tyr 705) in the original and recurrent tumor. The initial remarkable radiographic responses to IGF1R-antibody therapy was followed by resistance and then response to combined IGF1R plus mTOR inhibitor therapy in both patients, and then resistance to the combination regimen in one patient. In patient 1, upregulation of p-Akt and p-mTOR in the tumor that relapsed after initial response to IGF1R antibody might explain the resistance that developed, and the subsequent response to combined IGF1R plus mTOR inhibitor therapy. In patient 2, upregulation of mTOR was seen in the primary tumor, perhaps explaining the initial response to the IGF1R and mTOR inhibitor combination, while the resistant tumor that emerged showed activation of the ERK pathway as well.

Conclusion/Significance

Morphoproteomic analysis revealed that the mTOR pathway was activated in these two patients with advanced Ewing's sarcoma who showed response to combined IGF1R and mTOR inhibition, and the ERK pathway in the patient in whom resistance to this combination emerged. Our pilot results suggests that morphoproteomic assessment of signaling pathway activation in Ewing's sarcoma merits further investigation as a guide to understanding response and resistance signatures.

Genomic imprinting refers to a parent-of-origin specific effect on gene expression. At least 1% of genes in the human genome are modulated in this manner. We sought evidence for genomic imprinting in colorectal cancer by studying the ages at diagnosis in the offspring of 2,061 parent-child pairs in which both parent and child were affected by non syndromic colorectal cancer. Families were ascertained through the colon Cancer Family Registry [http://epi.grants.cancer.gov/CFR/] from both population-based and clinic-based sources. We found that the affected offspring of affected fathers were on average younger than offspring of affected mothers (55.8 vs 53.7 years; p=0.0003), but when divided into sons and daughters, this difference was driven entirely by younger age at diagnosis in daughters of affected fathers compared to sons (52.3 years vs 55.1 years; p=0.0004). A younger age at diagnosis in affected daughters of affected fathers was also observable in various subsets including families that met Amsterdam II Criteria, families that did not meet Amsterdam Criteria, and in families with documented normal DNA mismatch repair in tumors. Imprinting effects are not expected to be affected by the sex of the offspring. Possible explanations for these unexpected findings include: 1) an imprinted gene on the pseudoautosomal regions of the X chromosome; 2) an imprinted autosomal gene that affects a sex-specific pathway; or 3) an X-linked gene unmasked because of colonic tissue-specific preferential inactivation of the maternal X chromosome.

We have previously demonstrated that implanted microvessels form a new microcirculation with minimal host-derived vessel investment. Our objective was to define the vascular phenotypes present during neovascularization in these implants and identify post-angiogenesis events. Morphological, functional and transcriptional assessments identified three distinct vascular phenotypes in the implants: sprouting angiogenesis, neovascular remodeling, and network maturation. A sprouting angiogenic phenotype appeared first, characterized by high proliferation and low mural cell coverage. This was followed by a neovascular remodeling phenotype characterized by a perfused, poorly organized neovascular network, reduced proliferation, and re-associated mural cells. The last phenotype included a vascular network organized into a stereotypical tree structure containing vessels with normal perivascular cell associations. In addition, proliferation was low and was restricted to the walls of larger microvessels. The transition from angiogenesis to neovascular remodeling coincided with the appearance of blood flow in the implant neovasculature. Analysis of vascular-specific and global gene expression indicates that the intermediate, neovascular remodeling phenotype is transcriptionally distinct from the other two phenotypes. Therefore, this vascular phenotype likely is not simply a transitional phenotype but a distinct vascular phenotype involving unique cellular and vascular processes. Furthermore, this neovascular remodeling phase may be a normal aspect of the general neovascularization process. Given that this phenotype is arguably dysfunctional, many of the microvasculatures present within compromised or diseased tissues may not represent a failure to progress appropriately through a normally occurring neovascularization phenotype.

The external domains of the HIV-1 envelope glycoprotein (gp120 and the gp41 ectodomain, collectively known as gp140) contain all known viral neutralization epitopes. Various strategies have been used to create soluble trimers of the envelope to mimic the structure of the native viral protein, including mutation of the gp120-gp41 cleavage site, introduction of disulfide bonds, and fusion to heterologous trimerization motifs. We compared the effects on quaternary structure, antigenicity, and immunogenicity of three such motifs: T4 fibritin, a GCN4 variant, and the E. coli aspartate transcarbamoylase catalytic subunit. Fusion of each motif to the C-terminus of a non-cleavable JRCSF gp140(-) envelope protein led to enhanced trimerization but had limited effects on the antigenic profile and CD4 binding ability of the trimers. Immunization of rabbits provided no evidence that the trimerized gp140(-) constructs induced significantly improved neutralizing antibodies to several HIV-1 pseudoviruses, compared to gp140 lacking a trimerization motif. However, modest differences in both binding specificity and neutralizing antibody responses were observed among the various immunogens.

Purpose

Bevacizumab is an antibody against vascular endothelial growth factor (VEGF); sunitinib is an inhibitor of VEGF and related receptors. The safety and maximum tolerated dose (MTD) of sunitinib plus bevacizumab was assessed in this phase I trial.

Experimental Design

Patients with advanced solid tumors were treated on a 3+3 trial design. Patients received sunitinib daily (starting dose level 25 mg) for 4 weeks on followed by 2 weeks off and bevacizumab (starting dose level 5 mg/kg) on days 1, 15 and 29 of a 42-day cycle. Dose-limiting toxicities (DLTs) during the first 6-week cycle were used to determine the MTD.

Results

Thirty-eight patients were enrolled. Pts received a median of 3 cycles of treatment (range, 1–17+). There was one DLT (grade 4 hypertension) at 37.5 mg sunitinib and 5 mg/kg bevacizumab. Grade 3 or greater toxicity was observed in 87% of patients including hypertension (47%), fatigue (24%), thrombocytopenia (18%), proteinuria (13%), and hand-foot syndrome (13%). Dose modifications and delays were common at higher dose levels. No clinical or laboratory evidence of microangiopathic hemolytic anemia was observed. Seven patients had a confirmed RECIST-defined PR (18%; 95% confidence interval: 8–34%). Nineteen of the 32 patients with a post-baseline scan (59%) had at least some reduction in overall tumor burden (median 32%, range 3–73%).

Conclusions

The combination of sunitinib and bevacizumab in patients with advanced solid tumors is feasible, albeit with toxicity at higher dose levels and requiring dose modification with continued therapy. Anti-tumor activity was observed across multiple solid tumors.