MolMed (Italy)

<div>Abstract<p>Asparagine deamidation in peptides or in fibronectin fragments containing the asparagine-glycine-arginine sequence generates isoaspartate-glycine-arginine (<i>iso</i>DGR), a new αvβ3 integrin-binding motif. Because αvβ3 is expressed in angiogenic vessels, we hypothesized that <i>iso</i>DGR-containing peptides could be exploited as ligands for targeted delivery of drugs to tumor neovasculature. We found that a cyclic C<i>iso</i>DGRC peptide coupled to fluorescent nanoparticles (quantum dots) could bind αvβ3 integrin and colocalize with anti-CD31, anti-αvβ3, and anti-α5β1 antibodies in human renal cell carcinoma tissue sections, indicating that this peptide could efficiently recognize endothelial cells of angiogenic vessels. Using C<i>iso</i>DGRC fused to tumor necrosis factor α (TNF) we observed that ultralow doses (1–10 pg) of this product (called <i>iso</i>DGR-TNF), but not of TNF or CDGRC-TNF fusion protein, were sufficient to induce antitumor effects when administered alone or in combination with chemotherapy to tumor-bearing mice. The antitumor activity of <i>iso</i>DGR-TNF was efficiently inhibited by coadministration with an excess of free C<i>iso</i>DGRC, as expected for ligand-directed targeting mechanisms. These results suggest that <i>iso</i>DGR is a novel tumor vasculature–targeting motif. Peptides containing <i>iso</i>DGR could be exploited as ligands for targeted delivery of drugs, imaging agents, or other compounds to tumor vasculature. [Cancer Res 2008;68(17):7073–82]</p></div>

Collection of an adequate amount of autologous haematopoietic stem progenitor cells (HSPC) is required for ex vivo manipulation and successful engraftment for certain inherited disorders. Fifty-seven paediatric patients (age 0.5–11.4 years) underwent a bone marrow harvest for the purpose of HSPC gene therapy (GT), including adenosine deaminase-severe combined immunodeficiency (ADA-SCID), Wiskott–Aldrich syndrome (WAS) and metachromatic leukodystrophy (MLD) patients. Total nucleated cells and the percentage and absolute counts of CD34+ cells were calculated at defined steps of the procedure (harvest, CD34+ cell purification, transduction with the gene transfer vector and infusion of the medicinal product). A minimum CD34+ cell dose for infusion was 2 × 106/kg, with an optimal target at 5–10 × 106/kg. Median volume of bone marrow harvested was 34.2 ml/kg (range 14.2–56.6). The number of CD34+ cells collected correlated inversely with weight and age in all patients and particularly in the MLD children group. All patients reached the minimum target dose for infusion: median dose of CD34+ cells/kg infused was 10.3 × 106/kg (3.7–25.9), with no difference among the three groups. Bone marrow harvest of volumes > 30 ml/kg in infants and children with ADA-SCID, WAS and MLD is well tolerated and allows obtaining an adequate dose of a medicinal product for HSPC-GT.

7501 Background: Currently, there are no standard options for MPM patients who failed a pemetrexed-based chemotherapy (CT). NGR-hTNF, a tumor-targeted antivascular agent, displays antitumor activit...

By binding to the liver X receptor (LXR), oxysterols inhibit the expression of chemokine (C-C motif) receptor 7 (CCR7), hence impairing the migration of dendritic cells to secondary lymphoid organs and inhibiting antitumor immune responses. We have recently identified a new tumor-supporting activity of oxysterols, which recruit neutrophils within tumor microenvironment by a chemokine (C-X-C motif) receptor 2 (CXCR2)-dependent, LXR-independent mechanism.

3038 Background: Antitumor effects of NGR-hTNF (N), a tumor-targeted antivascular agent, are driven at low dose by an early vessel stabilization that greatly enhances both intratumoral CT uptake and T-cell infiltration. Synergism with CT was shown in immunocompetent mice, but not in nude mice lacking functional T cells. Methods: By an individual patient pooled analysis of 396 patients (pts) from 7 ph II trials in 6 tumor types, we estimated the effects of baseline PBLC on the antitumor activity of N (with or without CT) and CT alone. Low dose N (0.8 μg/m2) was given in combination with CT in 171 pts. Control groups of 140 and 85 pts receiving N and CT alone, respectively, were also analyzed. CT was doxorubicin or a platinum-based regimen. In all trials, response to therapy was assessed every 6 weeks by RECIST. Endpoints of interest were response rate (RR, complete plus partial response), disease control rate (DCR, RR plus stable disease), duration of response (DOR) and progression-free survival (PFS). In logistic and Cox regression analyses, PBLC data were dichotomized in high or low levels by the median cutpoint (1.5/mL; 95% CI, 1.4-1.6). Multivariate models included age, sex, PS and tumor type as covariates. Results: In both N-alone and CT-alone groups, there was no statistically significant difference in treatment effect according to baseline PBLC. Conversely, high PBLC were related to better treatment outcome in the N plus CT group, compared to low PBLC. In this N plus CT group, high PBLC (vs low) were associated with higher RR (OR=2.8; 95% CI, 1.2-6.3; p=.01) and DCR (OR=2.6; 1.3-4.9; p=.004), and with longer DOR (HR=0.39; 0.16-0.96; p=.04) and PFS (HR=0.60; 0.43-0.85; p=.004). For high vs low PBLC, RR was 29% vs 14%, DCR 76% vs 57%, median DOR 8.2 vs 6.3 months, and median PFS 5.0 vs 3.0 months, respectively. On multivariate analyses, high PBLC remained an independent predictor of increased RR (OR=2.7; p=.01) and DCR (OR=2.6; p=.005), and improved DOR (HR=0.36; p=.04) and PFS (HR=0.60; p=.005). Conclusions: Consistently with preclinical data, these results highlight the potential value of PBLC in predicting tumor response to NGR-hTNF in combination with CT, which merits further clinical validation Clinical trial information: NCT00994097-NCT00484432-NCT00484276-NCT00484211-NCT00483509-NCT00483080-NCT01358071.