Citations

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.

Object Acute revascularization has been associated with improved stroke outcomes. The Prolyse in Acute Cerebral Thromboembolism (PROACT II) trial achieved recanalization rates of 66%. The Multi Mechanical Embolus Removal in Cerebral Ischemia (Multi MERCI) trial achieved recanalization in 70% of patients. However, these interventional tools are not always successful. The Enterprise vascular reconstruction device was recently introduced for treatment of cerebral aneurysms previously untreatable with endovascular techniques. The authors evaluated a multicenter experience using this stent as a salvage revascularization tool for acute stroke treatment. Methods Four medical centers participated in a retrospective review of endovascularly treated patients with acute stroke for cases treated with the Enterprise stent after routine interventions had been unsuccessful. Data collected included preprocedure information, intraprocedure findings, and outcomes. Results Twenty patients with acute stroke (mean age 61.6 ± 22 years) were treated with the Enterprise stent. Ten patients received intravenous recombinant tissue plasminogen activator before catheter intervention, without improvement. Intraarterial interventions attempted unsuccessfully before Enterprise deployment included the Merci retriever (12 patients), angioplasty (7 patients), glycoprotein IIb–IIIa inhibitor administration (12 patients), intraarterial nitroglycerin (1 patient), Wingspan stent deployment (3 patients), and Xpert stent deployment (1 patient). The mean preintervention National Institutes of Health Stroke Scale (NIHSS) score was 17 ± 6 (median 17). All patients presented with a Thrombolysis in Myocardial Infarction (TIMI) score of 0 or 1. Revascularization was achieved in all patients (75% with a TIMI score of 3, 25% with a TIMI score of 2). Improvement (≥ 4 points on the NIHSS) was documented in 75% of patients. Mean NIHSS improvement from intervention to discharge was 8 ± 7 points (median 9 points). Conclusions These preliminary data suggest a potential benefit to the use of the Enterprise stent when routine intervention methods fail.

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]

Abstract Protein kinase Cι (PKCι) is an oncogene required for maintenance of the transformed phenotype of non–small cell lung cancer cells. However, the role of PKCι in lung tumor development has not been investigated. To address this question, we established a mouse model in which oncogenic KrasG12D is activated by Cre-mediated recombination in the lung with or without simultaneous genetic loss of the mouse PKCι gene, Prkci. Genetic loss of Prkci dramatically inhibits Kras-initiated hyperplasia and subsequent lung tumor formation in vivo. This effect correlates with a defect in the ability of Prkci-deficient bronchioalveolar stem cells to undergo Kras-mediated expansion and morphologic transformation in vitro and in vivo. Furthermore, the small molecule PKCι inhibitor aurothiomalate inhibits Kras-mediated bronchioalveolar stem cell expansion and lung tumor growth in vivo. Thus, Prkci is required for oncogene-induced expansion and transformation of tumor-initiating lung stem cells. Furthermore, aurothiomalate is an effective antitumor agent that targets the tumor-initiating stem cell niche in vivo. These data have important implications for PKCι as a therapeutic target and for the clinical use of aurothiomalate for lung cancer treatment. [Cancer Res 2009;69(19):7603–11]

Abstract Oncolytic virotherapy may mediate antitumor effects via direct oncolysis or immune-mediated tumor regression. Although the ability of oncolytic viruses to generate adaptive antitumor immunity has been characterized, their interactions with the innate immune system are relatively unclear. Using a human in vitro system, this study investigates the innate immunological consequences of reovirus therapy and its potential to activate NK cell-mediated antitumor activity. Dendritic cells (DC) loaded with reovirus-infected human melanoma Mel888 cells (DC-MelReo), but not reovirus-infected tumor cells alone, induced IFN-γ production within the NK cell population upon coculture with PBMC, in a cell-to-cell contact-dependent manner. DC-MelReo secreted the chemokines CCL2, 3, 4, 5, 7, 8, 11, and CXCL10; these culture supernatants induced NK cell chemotaxis. Coculture of DC-MelReo with purified NK cells induced reciprocal contact-dependent phenotypic DC maturation, while DC-MelReo elicited up-regulation of the activation marker CD69 on NK cells, in a partially contact and partially IL-12 dependent manner. Significantly, DC-MelReo induced NK cell cytotoxicity toward tumor cells by a type I IFN dependent mechanism. These data demonstrate that tumor infection by reovirus can act via DC to induce NK cell recruitment, activation, and cytotoxicity, along with reciprocal DC maturation. These findings suggest that reciprocal DC-NK cell interactions, following reovirus therapy, may play an important role in altering the immune milieu of the tumor microenvironment and mediating tumor regression.

Abstract Purpose: Reovirus is a naturally occurring oncolytic virus in clinical trials. Although tumor infection by reovirus can generate adaptive antitumor immunity, its therapeutic importance versus direct viral oncolysis is undefined. This study addresses the requirement for viral oncolysis and replication, and the relative importance of antitumor immunity and direct oncolysis in therapy. Experimental Design: Nonantigen specific T cells loaded with reovirus were delivered i.v. to C57BL/6 and severe combined immunodeficient mice bearing lymph node and splenic metastases from the murine melanoma, B16ova, with assessment of viral replication, metastatic clearance by tumor colony outgrowth, and immune priming. Human cytotoxic lymphocyte priming assays were done with dendritic cells loaded with Mel888 cells before the addition of reovirus. Results: B16ova was resistant to direct oncolysis in vitro, and failed to support reovirus replication in vitro or in vivo. Nevertheless, reovirus purged lymph node and splenic metastases in C57BL/6 mice and generated antitumor immunity. In contrast, reovirus failed to reduce tumor burden in severe combined immunodeficient mice bearing either B16ova or reovirus-sensitive B16tk metastases. In the human system, reovirus acted solely as an adjuvant when added to dendritic cells already loaded with Mel888, supporting priming of specific antitumor cytotoxic lymphocyte, in the absence of significant direct tumor oncolysis; UV-treated nonreplicating reovirus was similarly immunogenic. Conclusion: The immune response is critical in mediating the efficacy of reovirus, and does not depend upon direct viral oncolysis or replication. The findings are of direct relevance to fulfilling the potential of this novel anticancer agent.