An efficient intrathecal delivery of small interfering RNA to the spinal cord and peripheral neurons

We have developed a highly effective method for in vivo gene silencing in the spinal cord and dorsal root ganglia (DRG) by a cationic lipid facilitated delivery of synthetic, small interfering RNA (siRNA). A siRNA to the delta opioid receptor (DOR), or a mismatch RNA, was mixed with the transfection reagent, i-Fect™ (vehicle), and delivered as repeated daily bolus doses (0.5 μg to 4 μg) via implanted intrathecal catheter to the lumbar spinal cord of rats. Twenty-four hours after the last injection, rats were tested for antinociception by the DOR selective agonist, [D-Ala(2), Glu(4)]deltorphin II (DELT), or the mu opioid receptor (MOR) selective agonist, [D-Ala(2), N-Me-Phe(4), Gly-ol(5)]enkephalin (DAMGO). Pretreatment with the siRNA, but not the mismatch RNA or vehicle alone, blocked DELT antinociception dose-dependently. The latter was concomitant with a reduction in the spinal immunoreactivity and receptor density of DOR, and in DOR transcripts in the lumbar DRG and spinal dorsal horn. Neither siRNA nor mismatch RNA pretreatment altered spinal immunoreactivity of MOR or antinociception by spinal DAMGO, and had no effect on the baseline thermal nociceptive threshold. The inhibition of function and expression of DOR by siRNA was reversed by 72 hr after the last RNA injection. The uptake of fluorescence-tagged siRNA was detected in both DRG and spinal cord. The low effective dose of siRNA/i-Fect™ complex reflects an efficient delivery of the siRNA to peripheral and spinal neurons, produced no behavioral signs of toxicity. This delivery method may be optimized for other gene targets

Cancer Survival and Excess Mortality Estimates among Adolescents and Young Adults in Western Australia, 1982-2004: A Population-Based Study

Background: Data are limited on cancer outcomes in adolescents and young adults. Methods: Based on data from the Western Australian Data Linkage System, this study modelled survival and excess mortality in all adolescents and young adults aged 15-39 years in Western Australia who had a diagnosis of cancer in the period 1982-2004. Relative survival and excess all-cause mortality for all cancers combined and for principal tumour subgroups were estimated, using the Ederer II method and generalised linear Poisson modelling, respectively. Results: A cancer diagnosis in adolescents and young adults conferred substantial survival decrement. However, overall outcomes improved over calendar period (excess mortality hazard ratio [HR], latest versus earliest diagnostic period: 0.52, trend <0.0001). Case fatality varied according to age group (HR, oldest versus youngest: 1.38, trend <0.0001), sex (HR, female versus male: 0.66, 95% confidence interval [CI] 0.62-0.71), ethnicity (HR, Aboriginal versus others: 1.47, CI 1.23-1.76), geographical area (HR, rural/remote versus urban: 1.13, CI 1.04-1.23) and residential socioeconomic status (HR, lowest versus highest quartile: 1.14, trend <0.05). Tumour subgroups differed substantially in frequency according to age group and sex, and were critical outcome determinants. Conclusions: Marked progressive calendar-time improvement in overall outcomes was evident. Further research is required to disentangle the contributions of tumour biology and health service factors to outcome disparities between ethno-demographic, geographic and socioeconomic subgroups of adolescents and young adults with cancer. © 2013 Haggar et al

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

Remission of ordinary psoriasis following a short clearance course of cyclosporin

We set out to show that the assumption is incorrect that continuous treatment with cyclosporin is necessary in psoriasis, as this tenet forms a basis for current recommended treatment regimens. Sixty patients with mild to moderate plaque psoriasis were allocated at random to treatment with oral cyclosporin 5 mg/kg/day (30 patients) or topical dithranol and ultraviolet B therapy (30 patients) for up to 16 weeks until clear (median time 6 weeks cyclosporin and 8 dithranol), and the times to relapse compared. The patients were seen monthly for up to 8 months, and the severity and the extent of psoriasis were assessed. Relapse, defined as return of psoriasis to 50% of the area at the start of the trial or patient demand for further treatment, was not significantly different between the groups (hazard ratio 1.11, 95% CI 0.55-2.32). No patients suffered a rebound of severe disease and none relapsed in the first 8 weeks after stopping treatment. The relapse rate was higher following cyclosporin from 8 to 28 weeks after treatment and following dithranol from 28 to 34 weeks. The patients with arthritis had a higher median joint severity score at relapse than prior to treatment with cyclosporin. At the end of 8 months, 5 patients treated with dithranol and 8 patients with cyclosporin remained clear, 75% and 67% having relapsed. We conclude that rapid relapse does not occur after clearance of mild to moderate plaque psoriasis with cyclosporin and the relapse rate was no different from dithranol treatment