Citations

The sensitivity of baroreflex control of sympathetic nerve activity (SNA) represents the responsiveness of SNA to changes in blood pressure. In a slightly different analysis, the baroreflex threshold measures the probability of whether a sympathetic burst will occur at a given diastolic blood pressure. We hypothesized that baroreflex threshold analysis could be used to estimate the sensitivity of the sympathetic baroreflex measured by the pharmacological modified Oxford test. We compared four measures of sympathetic baroreflex sensitivity in 25 young healthy participants: the “gold standard” modified Oxford analysis (nitroprusside and phenylephrine), nonbinned spontaneous baroreflex analysis, binned spontaneous baroreflex analysis, and threshold analysis. The latter three were performed during a quiet baseline period before pharmacological intervention. The modified Oxford baroreflex sensitivity was significantly related to the threshold slope ( r = 0.71, P < 0.05) but not to the binned (1 mmHg bins) and the nonbinned spontaneous baroreflex sensitivity ( r = 0.22 and 0.36, respectively, P > 0.05), which included burst area. The threshold analysis was also performed during the modified Oxford manipulation. Interestingly, we found that the threshold analysis results were not altered by the vasoactive drugs infused for the modified Oxford. We conclude that the noninvasive threshold analysis technique can be used as an indicator of muscle SNA baroreflex sensitivity as assessed by the modified Oxford technique. Furthermore, the modified Oxford method does not appear to alter the properties of the baroreflex.

Purpose No established treatment exists for pancreatic neuroendocrine tumor (NET) progression after failure of chemotherapy. Everolimus (RAD001), an oral inhibitor of mammalian target of rapamycin, in combination with octreotide has demonstrated encouraging antitumor activity in patients with NETs. Patients and Methods This open-label, phase II study assessed the clinical activity of everolimus in patients with metastatic pancreatic NETs who experienced progression on or after chemotherapy. Patients were stratified by prior octreotide therapy (stratum 1: everolimus 10 mg/d, n = 115; stratum 2: everolimus 10 mg/d plus octreotide long-acting release [LAR], n = 45). Tumor assessments (using Response Evaluation Criteria in Solid Tumors) were performed every 3 months. Chromogranin A (CgA) and neuron-specific enolase (NSE) were assessed monthly if elevated at baseline. Trough concentrations of everolimus and octreotide were assessed. Results By central radiology review, in stratum 1, there were 11 partial responses (9.6%), 78 patients (67.8%) with stable disease (SD), and 16 patients (13.9%) with progressive disease; median progression-free survival (PFS) was 9.7 months. In stratum 2, there were two partial responses (4.4%), 36 patients (80%) with SD, and no patients with progressive disease; median PFS was 16.7 months. Patients with an early CgA or NSE response had a longer PFS compared with patients without an early response. Coadministration of octreotide LAR and everolimus did not impact exposure to either drug. Most adverse events were mild to moderate and were consistent with those previously seen with everolimus. Conclusion Daily everolimus, with or without concomitant octreotide LAR, demonstrates antitumor activity as measured by objective response rate and PFS and is well tolerated in patients with advanced pancreatic NETs after failure of prior systemic chemotherapy.

Abstract Productive T cell activation requires efficient reorganization of the actin cytoskeleton. We showed previously that the actin-regulatory protein, hematopoietic lineage cell-specific protein 1 (HS1), is required for the stabilization of F-actin and Vav1 at the immunological synapse and for efficient calcium responses. The Tec family kinase IL-2-inducible T cell kinase (Itk) regulates similar aspects of T cell activation, suggesting that these proteins act in the same pathway. Using video microscopy, we show that T cells lacking Itk or HS1 exhibited similar defects in actin responses, extending unstable lamellipodial protrusions upon TCR stimulation. HS1 and Itk could be coimmunoprecipitated from T cell lysates, and GST-pulldown studies showed that Itk’s Src homology 2 domain binds directly to two phosphotyrosines in HS1. In the absence of Itk, or in T cells overexpressing an Itk Src homology 2 domain mutant, HS1 failed to localize to the immunological synapse, indicating that Itk serves to recruit HS1 to sites of TCR engagement. Because Itk is required for phospholipase C (PLC)γ1 phosphorylation and calcium store release, we examined the calcium signaling pathway in HS1−/− T cells in greater detail. In response to TCR engagement, T cells lacking HS1 exhibited diminished calcium store release, but TCR-dependent PLCγ1 phosphorylation was intact, indicating that HS1’s role in calcium signaling is distinct from that of Itk. HS1-deficient T cells exhibited defective cytoskeletal association of PLCγ1 and altered formation of PLCγ1 microclusters. We conclude that HS1 functions as an effector of Itk in the T cell actin-regulatory pathway, and directs the spatial organization of PLCγ1 signaling complexes.

Peripheral arterial disease (PAD) is common in patients with severe coronary artery disease (CAD) and is considered a relative contraindication to external enhanced counterpulsation (EECP), but there are no data that define the efficacy and safety of EECP in patients with PAD. The International EECP Patient Registry (IEPR) was used to compare initial post-therapy and 2-year follow-up clinical outcomes and adverse event rates in patients with and without PAD. From January 2002 to October 2004, 2126 patients were enrolled in the IEPR, of whom 493 (23%) had a history of PAD. Immediately following EECP, the reduction in angina (≥ 1 Canadian Cardiovascular Society class) was similar in patients with and without PAD (76.6% vs 79.0%, p = 0.27) as was improvement in the Duke Activity Score Index (DASI) score (+4.7% vs +6.1%, p < 0.001). Both angina reduction and DASI score improvement were sustained at 2 years. PAD patients discontinued EECP more frequently (12.0% vs 8.5%, p < 0.05), but lower extremity ulceration did not occur more frequently in patients with PAD (3.7% vs 2.7%, p = 0.26). Rates of death (17.1% vs 8.6%, p < 0.001) and myocardial infarction (9.5% vs 5.0%, p < 0.001) were, as expected, higher in patients with PAD compared to patients without PAD at 2 years. In conclusion, while PAD patients constitute a high-risk cohort with known higher adverse event rates, EECP led to similar short- and long-term improvements in angina and quality of life for individuals with PAD compared to those without PAD.

PurposeLenalidomide is a novel immunomodulatory agent with antiproliferative activities. Given its efficacy in a wide range of hematologic malignancies, we conducted a phase II trial (NHL-001) of single-agent lenalidomide in indolent non-Hodgkin's lymphoma (NHL).Patients and MethodsPatients with relapsed/refractory indolent NHL were eligible, with no limit on the number of previous therapies. Oral lenalidomide 25 mg was self-administered once daily on days 1 to 21 of every 28-day cycle for up to 52 weeks as tolerated, or until disease progression. The primary end point was objective response rate (ORR), with secondary end points of duration of response (DR), progression-free survival (PFS), and safety.ResultsForty-three enrolled patients were assessable for response and safety. Patients received a median of three prior systemic therapies (range, 1 to 17) and half were refractory to last therapy. ORR was 23% (10 of 43), including a 7% complete response (CR) or unconfirmed CR rate. Twenty-seven percent (six of 22) of patients with follicular lymphoma grade 1 or 2, and 22% (four of 18) with small lymphocytic lymphoma responded to therapy. Median DR was not reached, but was longer than 16.5 months with seven of 10 responses ongoing at 15 to 28 months. Median PFS for the whole group was 4.4 months (95% CI, 2.5 to 10.4 months). Adverse events were predictable and manageable; the most common grade 3 or 4 adverse events were neutropenia (30% and 16%, respectively) and thrombocytopenia (14% and 5%, respectively).ConclusionOral lenalidomide monotherapy produces durable responses with manageable adverse events in patients with relapsed/refractory indolent NHL, warranting further investigation of treatment for indolent NHL.

Abstract Our preclinical and clinical trials using a replication-defective adenoviral vector expressing IFN-β have shown promising results for the treatment of malignant mesothelioma. Based on the hypotheses that a replication-competent vesicular stomatitis virus (VSV) oncolytic vector would transduce more tumor cells in vivo, that coexpression of the immunostimulatory IFN-β gene would enhance the immune-based effector mechanisms associated both with regression of mesotheliomas and with VSV-mediated virotherapy, and that virus-derived IFN-β would add further safety to the VSV platform, we tested the use of IFN-β as a therapeutic transgene expressed from VSV as a novel treatment for mesothelioma. VSV-IFN-β showed significant therapy against AB12 murine mesotheliomas in the context of both local and locoregional viral delivery. Biologically active IFN-β expressed from VSV added significantly to therapy compared with VSV alone, dependent in part on host CD8+ T-cell responses. Immune monitoring suggested that these antitumor T-cell responses may be due to a generalized T-cell activation rather than the priming of tumor antigen–specific T-cell responses. Finally, IFN-β also added considerable extra safety to the virus by providing protection from off-target viral replication in nontumor tissues and protected severe combined immunodeficient mice from developing lethal neurotoxicity. The enhanced therapeutic index provided by the addition of IFN-β to VSV therefore provides a powerful justification for the development of this virus for future clinical trials. [Cancer Res 2009;69(19):7713–20]

Abstract Background: Increased urinary albumin excretion is a well-documented diagnostic and prognostic biomarker for renal disease. Urinary albumin is typically measured in clinical settings by immunoassay methods. However, neither a reference method nor a urine albumin calibration reference material is currently available. Methods: We quantified urinary albumin in patient samples by using 3 commercially available reagent systems: DiaSorin SPQ™ and Beckman Coulter LX® 20 (immunoturbidimetric), and Siemens Immulite® (competitive immunoassay). Results were compared to values obtained by protein-cleavage liquid chromatography–tandem mass spectrometry (LC-MS/MS). Results: In general, results from the 3 immunoassays agreed with results from LC-MS/MS. However, the SPQ results showed a negative bias across all ranges of albuminuria [(0–200 mg/L, y = 0.91x – 3.74 (CI 0.86–0.96); &gt; 200 mg/L, y = 0.88x – 40.30 (CI 0.76–1.00)], whereas the LX 20 showed minimal bias in the 0–200 mg/L range [y = 0.97x − 88 (CI 0.92–1.02)] and the Immulite assay showed positive bias in the 0–200 mg/L range [y = 1.15x – 4.38 (CI 1.09–1.20)]. Conclusions: These results showed a reasonable quantification of urinary albumin by representative polyclonal and monoclonal immunoassays compared to an LC-MS/MS assay. In addition, the results do not suggest the presence of nonimmunoreactive albumin in urine. However, differences in analytic performance between assays support the need for a reference calibration material and reference method to standardize clinical laboratory measurements of urinary albumin.

Abstract We have a long-term interest in the connectivity between autoimmunity and tumor rejection. However, outside of the melanocyte/melanoma paradigm, little is known about whether autoimmune responses to normal tissue can induce rejection of tumors of the same histologic type. Here, we induced direct, pathogen-like cytotoxicity to the normal pancreas in association with the immune adjuvant heat shock protein 70. In sharp contrast to our studies with a similar approach for the treatment of prostate cancer, inflammatory killing of the normal pancreas induced a Th1-like, anti-self-response to pancreatic antigens, which was rapidly suppressed by a concomitant suppressive regulatory T cell (Treg) response. Interestingly, even when Treg cells were depleted, the Th1-like response was insufficient to induce significant ongoing autoimmunity. However, the Th1-like response to antigens expressed in the pancreas at the time of damage was sufficient to induce rejection of tumors expressing either a foreign (ova) antigen or fully syngeneic tumor antigens (on Panc02 tumor cells), provided that Treg were depleted before inflammatory killing of the normal pancreas. Taken together, these data indicate that profound differences exist between the immunoprotective mechanisms in place between different tissues (pancreas and prostate) in their response to pathogen-like damage. Moreover, they also show that, although multiple layers of immunologic safeguards are in place to prevent the development of severe autoimmune consequences in the pancreas (in contrast to the prostate), tumor rejection responses can still be decoupled from pathologic autoimmune responses in vivo, which may provide novel insights into the immunotherapeutic treatment of pancreatic cancer. [Cancer Res 2009;69(19):7767–74]