Citations

AbstractRobotic surgical techniques are now being applied in the setting of retroperitoneal lymphadenectomy (RPLND) for testicular cancer. While laparoscopic RPLND has not been widely accepted, reports of robot assisted RPLND (RARPLND) are emerging. This manuscript will review the application of RPLND for testicular cancer, evolution of minimally invasive techniques, the controversies, and current status of RARPLND. J. Surg. Oncol. 2015;112:736–740. © 2015 Wiley Periodicals, Inc.

Extracellular RNAs (exRNAs) have been identified in all tested biofluids and have been associated with a variety of extracellular vesicles, ribonucleoprotein complexes and lipoprotein complexes. Much of the interest in exRNAs lies in the fact that they may serve as signalling molecules between cells, their potential to serve as biomarkers for prediction and diagnosis of disease and the possibility that exRNAs or the extracellular particles that carry them might be used for therapeutic purposes. Among the most significant bottlenecks to progress in this field is the lack of robust and standardized methods for collection and processing of biofluids, separation of different types of exRNA‐containing particles and isolation and analysis of exRNAs. The Sample and Assay Standards Working Group of the Extracellular RNA Communication Consortium is a group of laboratories funded by the U.S. National Institutes of Health to develop such methods. In our first joint endeavour, we held a series of conference calls and in‐person meetings to survey the methods used among our members, placed them in the context of the current literature and used our findings to identify areas in which the identification of robust methodologies would promote rapid advancements in the exRNA field.

The large diversity and volume of extracellular RNA (exRNA) data that will form the basis of the exRNA Atlas generated by the Extracellular RNA Communication Consortium pose a substantial data integration challenge. We here present the strategy that is being implemented by the exRNA Data Management and Resource Repository, which employs metadata, biomedical ontologies and Linked Data technologies, such as Resource Description Framework to integrate a diverse set of exRNA profiles into an exRNA Atlas and enable integrative exRNA analysis. We focus on the following three specific data integration tasks: (a) selection of samples from a virtual biorepository for exRNA profiling and for inclusion in the exRNA Atlas; (b) retrieval of a data slice from the exRNA Atlas for integrative analysis and (c) interpretation of exRNA analysis results in the context of pathways and networks. As exRNA profiling gains wide adoption in the research community, we anticipate that the strategies discussed here will increasingly be required to enable data reuse and to facilitate integrative analysis of exRNA data.

Ten ongoing studies designed to test the possibility that extracellular RNAs may serve as biomarkers in human disease are described. These studies, funded by the NIH Common Fund Extracellular RNA Communication Program, examine diverse extracellular body fluids, including plasma, serum, urine and cerebrospinal fluid. The disorders studied include hepatic and gastric cancer, cardiovascular disease, chronic kidney disease, neurodegenerative disease, brain tumours, intracranial haemorrhage, multiple sclerosis and placental disorders. Progress to date and the plans for future studies are outlined.

SummaryBackgroundTemporary faecal diversion is sometimes used for management of refractory perianal Crohn's disease (CD) with variable success.AimsTo perform a systematic review with meta‐analysis to evaluate the effectiveness, long‐term outcomes and factors associated with success of temporary faecal diversion for perianal CD.MethodsThrough a systematic literature review through 15 July 2015, we identified 16 cohort studies (556 patients) reporting outcomes after temporary faecal diversion. We estimated pooled rates [with 95% confidence interval (CI)] of early clinical response, attempted and successful restoration of bowel continuity after temporary faecal diversion (without symptomatic relapse), and rates of re‐diversion (in patients with attempted restoration) and proctectomy (with or without colectomy and end‐ileostomy). We identified factors associated with successful restoration of bowel continuity.ResultsOn meta‐analysis, 63.8% (95% CI: 54.1–72.5) of patients had early clinical response after faecal diversion for refractory perianal CD. Restoration of bowel continuity was attempted in 34.5% (95% CI: 27.0–42.8) of patients, and was successful in only 16.6% (95% CI: 11.8–22.9). Of those in whom restoration was attempted, 26.5% (95% CI: 14.1–44.2) required re‐diversion because of severe relapse. Overall, 41.6% (95% CI: 32.6–51.2) of patients required proctectomy after failure of temporary faecal diversion. There was no difference in the successful restoration of bowel continuity after temporary faecal diversion in the pre‐biological or biological era (13.7% vs. 17.6%, P = 0.60), in part due to selection bias. Absence of rectal involvement was the most consistent factor associated with restoration of bowel continuity.ConclusionsTemporary faecal diversion may improve symptoms in approximately two‐thirds of patients with refractory perianal Crohn's disease, but bowel restoration is successful in only 17% of patients.

Abstract We have developed the use of reovirus as a systemically delivered oncolytic agent in both pre-clinical models and in early Phase clinical trials. Reovirus has direct oncolytic activity against many human/murine tumor cells, partly because of disruption of the PKR-mediated anti-viral response in malignant cells. In addition however, we have shown that anti-tumor therapy is directly associated with immune activation by virus replication in tumors. The immune mechanisms of therapy include both innate immune activation against virally infected tumor cells, as well as the generation of adaptive anti tumor immune responses as a result of in vivo priming against tumor associated antigens released during that killing. Therefore, to exploit the immune components of reovirus anti-tumor therapy, we hypothesized that the combination of reovirus therapy with systemic checkpoint inhibition would augment therapeutic efficacy. To test the hypothesis, we used C57Bl/6 mice, an immune-competent murine model, with established subcutaneous (s.c.) B16 melanomas. In this model, intra-tumoral injection of reovirus into s.c. tumors generated moderate therapy. Provision of systemic anti-PD-1 antibody along with i.t. reovirus, significantly enhanced survival compared to i.t. reovirus alone (p<0.01) and led to >40% of mice being cured long term. Immune analysis suggested that the enhanced therapeutic benefit of reovirus plus checkpoint inhibition is contributed by at least two factors. First, blockade of PD-1 significantly enhanced the ability of NK cells to recognize (TNF-α secretion), and kill, reovirus-infected target tumor cells. Second, anti PD-1 antibody led to a significant reduction in Treg activity in reovirus-treated mice, with the overall effect of increasing the adaptive CD8+ anti-tumor T cell response. Furthermore, in vivo depletion studies demonstrated that NK cells had a dramatic effect in reducing the therapeutic efficacy of reovirus plus anti-PD-1 therapy. Overall, the results indicate that combination therapy of reovirus with PD-1 blockade confers significant survival benefit, by augmenting tumor-specific NK responses and specifically attenuating tumor-specific immunosuppression. These data also suggest that combination of PD-1 inhibition therapy with reovirus oncolytic/immunotherapy represents a readily translatable method to enhance the therapeutic efficacy. Citation Format: Karishma Rajani, Christopher Parrish, Kevin Shim, Liz Ilett, Fiona Errington-Mais, Jill Thompson, Tim Kottke, Rosa Maria-Diaz, Peter Selby, Hardev Pandha, Kevin Harrington, Alan Melcher, Matt Coffey, Shane Zaidi, Richard Vile. Combination therapy of reovirus and PD-1 blockade effectively establishes tumor control via innate and adaptive immune responses. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1360. doi:10.1158/1538-7445.AM2015-1360

Abstract Background: In United States there will be an estimated 74,690 new diagnoses and 15,580 deaths in 2014 due to bladder cancer. Lack of reliable markers of early disease and limited chemotherapy options have resulted in poor patient outcomes. A better approach is to treat patients with early intervention using targeted therapy. Arginine metabolic pathway has been identified to be deregulated in bladder cancer. Arginine is either derived from the microenvironment or synthesized by cells containing arginosuccinate synthase I (ASS1). Arginine undergoes subsequent conversion to nitric oxide (NO), which which can activate numerous intracellular signaling mediators, including guanylate cyclase (GC). We evaluated dual targeting of this metabolic pathway by arginine deprivation (ADI-PEG 20, Polaris Pharmaceuticals, San Diego, CA) and NO chelation (Cobinamide) as a therapy for bladder cancer. Experimental Design: Expression of arginine-NO pathway components in FFPE tissue sections was assessed by IHC and correlated with histopathology, outcomes and progression to identify pathway activation during early and late disease and stratified based on moderate to strong expression (2+, 3+) compared to absent to weak expression (0, 1+). In addition, a panel of bladder cell lines was screened for arginine-NO pathway components by immunoblotting and representative ASS1 negative and positive cells were used to evaluate the effects of arginine deprivation and/or NO chelation in vitro on colony formation and cell viability by clonogenic and MTT assays. Effects of NO production on bladder cancer survival and motility was assessed utilizing siRNA gene silencing and small molecule inhibitors. Effects of arginine deprivation by ADI-PEG 20 treatment in vivo was assessed by a mouse xenograft model. Results: Analysis of human tumors showed that ASS1 loss and increase in NOS occurred early in the course of bladder neoplastic progression. We identified loss of the ASS1 enzyme in bladder cancer cells and compensatory dependence on extracellular arginine, which can be successfully targeted using arginine removal to induce bladder cancer cell death, both in vitro and in vivo. We also identified increased nitric oxide synthase (NOS; the enzyme that catalyzes NO production) and GC activation in invasive bladder cancer cell lines. We characterized the effects of NO production on bladder cancer cell survival, growth and motility. Disruption of the NO pathway through gene silencing and small molecule inhibitors resulted in decreased cell survival, migration and invasion. Conclusions: Thus, dual targeting of this metabolic pathway using arginine chelation by the arginine degrading enzyme ADI-PEG20 and NO scavenging by a novel compound Cobinamide can be a potential mechanism to prevent development and/or progression of early bladder neoplasia. Citation Format: Divya Sahu, Sounak Gupta, Andrew M. Hau, Paul Elson, John Bomalaski, Gerry R. Boss, Donna E. Hansel. Targeting the arginine-nitric oxide pathway to arrest development and progression of invasive bladder cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4712. doi:10.1158/1538-7445.AM2015-4712

Abstract Introduction: Relapsed and refractory multiple myeloma (MM) remains a significant clinical challenge and drugs with new mechanisms of action to overcome resistance are needed. Constitutive activation of the PI3K/Akt/mTOR pathway in MM promotes tumorigenesis through propagation of the cell cycle, protein synthesis, and inhibition of apoptosis. Anti-MM effects of rapalogs are limited due to feedback activation of the PI3K/Akt signaling pathway. Agents capable of targeting PI3K and mTORC1 or both mTORC1/C2 are able to partially overcome such resistance mechanisms. However, the mTORC2 mediated increase in pAkt (Ser473) after PI3K/mTORC1 inhibition and the activation of PI3K after mTORC1/C2 inhibition could still contribute to resistance to such agents. We sought to investigate the effects of SPR965 (synthesized and provided by Sphaera Pharma, Singapore under an MTA), an orally bioavailable novel small molecule with inhibition of class 1 PI3 kinase and mTORC1/C2 kinases on MM cell lines and patient cells. Results: SPR965 induced cytotoxicity and inhibited proliferation in all MM cell lines examined with IC50 values between 25-500nM. To understand if SPR965 induced apoptotic cell death, annexin/PI staining followed by flow cytometric assays were performed, which showed a clear increase in cells undergoing apoptosis. Western blots showed increase in caspase-3, -9, and PARP cleavage confirming apoptotic induction by SPR965. Importantly, SPR965 caused potent increase in apoptosis in cytogenetically distinct MM patient cells. Next, we examined the mechanism of action of SPR965. SPR965 caused potent mTORC1 inhibition evidenced by decreased p4E-BP1, p-p70S6K, and pS6 at doses as low as 25nM. SPR965 was able to inhibit PI3K activity as shown by decreased pPDK1 and pBTK at slightly higher concentrations of 75nM. Phosphorylation of Akt S473, a TORC2 substrate, increased at initial low concentrations of SPR965, but was attenuated at concentrations of 100 nM and above, demonstrating dose-dependent inhibition of mTORC2. Such effects were also observed when we performed western blots on MM patient derived primary plasma cells. Increased levels of p27 (KIP1) were observed suggestive of G1 growth arrest, which was confirmed on cell cycle analysis. Since SPR965 caused an increase in pAkt (both T308 and S473) at doses up to 75nM, we examined if SPR965 was able to synergize with an Akt inhibitor MK2206 at doses lower than 75nM. Our results showed potent synergy suggesting that the pAkt up regulation contributes to partial resistance, which is inhibited by SPR965 at doses of 100nM and higher, doses that are still clinically achievable. Conclusion: Our findings demonstrate SPR965 induces apoptosis of MM cells through the inhibition of PI3K and mTORC1/C2 activity. Further studies are underway to better characterize the mechanism of action of SPR965, all of which will be informative for the drug to be used as a single agent or in combination with other agents in relapsed MM. Citation Format: Jeremy T. Larsen, Vijay Ramakrishnan, Jessica Haug, Teresa Kimlinger, Somdutta Sen, Dinesh Mahajan, Sundeep Dugar, S. Vincent Rajkumar, Shaji K. Kumar. Preclinical activity of dual PI3K/mTOR inhibitor SPR965 in multiple myeloma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2653. doi:10.1158/1538-7445.AM2015-2653