Autoimmune diseases such as multiple sclerosis (MS) are typified by the misrecognition of self-antigen and the clonal expansion of autoreactive T cells. Antigen-specific immunotherapies (antigen-SITs) have long been explored as a means to desensitize patients to offending self-antigen(s) with the potential to retolerize the immune response. Soluble antigen arrays (SAgAs) are composed of hyaluronic acid (HA) cografted with disease-specific autoantigen (proteolipid protein peptide) and an ICAM-1 inhibitor peptide (LABL). SAgAs were designed as an antigen-SIT that codeliver peptides to suppress experimental autoimmune encephalomyelitis (EAE), a murine model of MS. Codelivery of antigen and cell adhesion inhibitor (LABL) conjugated to HA was essential for SAgA treatment of EAE. Individual SAgA components or mixtures thereof reduced proinflammatory cytokines in cultured splenocytes from EAE mice; however, these treatments showed minimal to no in vivo therapeutic effect in EAE mice. Thus, carriers that codeliver antigen and a secondary "context" signal (e.g., LABL) in vivo may be an important design criteria to consider when designing antigen-SIT for autoimmune therapy.
<p>The supplementary information contains 10 figures and 3 tables. Figures S1-S8 provide supplementary experimental results, describing the effect of olaparib on BRCA1 and RAD51 protein expression (Fig S1); FOXM1 isoform expression in ovarian carcinoma (Fig S2); Synergistic effects of thiostrepton and olaparib or carboplatin (Fig S3); Alterations in gene expression and pathways affected by thiostrepton (Fig S4); ENCODE data analysis of FOXM1 binding sites in HR genes (Fig S5); Effects of thiostrepton on HR genes'' expression and cell cycle (Fig S6); The effect of thiostrepton and olaparib or carboplatin on DNA damage (Fig S7); and the effect of thiostrepton on rucaparib sensitivity (Fig S8). Figure S9 and S10 contains results describing efficiency of thiostrepton encapsulation in micelles (Fig S9) and analysis of particle sizes of micelles (Fig S10). The supplement information also contains materials and methods associated with the supplementary figures. Finally, the document contains data describing the zeta potential of micelles (Table S1), qPCR primers'' sequences (Table S2) and the description of datasets from Connectivity Map project that was used in this study (Table S3).</p>
278 Background: The most successful cancer chemotherapy regimens usually involve the administration of multiple cytotoxic agents simultaneously. Because different chemotherapies may have different mechanisms of action; it is difficult for cancer cells to become resistant to combination therapy. Recent investigations have discovered that nitric oxide (NO) may be involved in the reversal of cisplatin (CDDP) resistance in chemotherapy. Therefore, we sought to develop a combination regimen involving a NO-releasing prodrug (NO1) and cisplatin for the treatment of breast cancer. Methods: The prodrug NO1 was synthesized to be localized in tumor cells and to release nitric oxide over 10 hours. The antiproliferative activity of NO1 was determined in human breast cancer cell line, MDA-MB-468LN. To evaluate the effectiveness of the CDDP/NO combination regimen, platinum-resistant MDA-MB-468LN cells were treated with either cisplatin alone ([CDDP]=0.01, 0.02 or 0.03 mM) or the CDDP/NO combination ([CDDP]=0.01, 0.02 or 0.03 mM; [NO1]=0.02 mM). The cell viability was determined 48 hours post-treatment using a live/dead trypan blue exclusion assay. Results: The toxicity to breast cancer cells was higher than JS-K, a systemic NO agent currently in preclinical development. (NO1: IC 50 =26µM; JS-K: IC 50 =42 µM). In addition, NO1 had a long sustained release of nitric oxide, approximately one fold longer than JS-K (NO1: t1/2=6 h; JS-K: t1/2=3 h). The combination treatments resulted in 6.6-, 6.9- and 7.5-fold increase in cell death compared to cisplatin treatment alone at cisplatin concentrations of 0.01, 0.02 and 0.03 mM, respectively. A subsequent study in a murine xenograft of head and neck cancer found NO-1 conjugated to nanoparticles increased survival a mean of 10 weeks compared to controls (p<0.0001). Conclusions: Nitric oxide prodrug NO-1 and nanoparticles of it have high anticancer activity in vivo and they can reverse platinum resistance in vitro. Ongoing studies are examining the safety and efficacy of CDDP/NO combination therapy in mouse xenografts of human breast cancer.