The CD34 antigen is expressed by committed and uncommitted hematopoietic progenitor cells and is increasingly used to assess stem cell content of peripheral blood progenitor cell (PBPC) collections. Quantitative CD34 expression in PBPC collections has been suggested to correlate with engraftment kinetics of PBPCs infused after myeloablative therapy. We analyzed the engraftment kinetics as a function of CD34 content in 692 patients treated with high-dose chemotherapy (HDC). Patients had PBPCs collected after cyclophosphamide based mobilization chemotherapy with or without recombinant human granulocyte colony-stimulating factor (rhG-CSF) until > or = 2.5 x 10(6) CD34+ cells/kg were harvested. Measurement of the CD34 content of PBPC collections was performed daily by a central reference laboratory using a single technique of CD34 analysis. Forty-five patients required a second mobilization procedure to achieve > or = 2.5 x 10(6) CD34+ cells/kg and 15 patients with less than 2.5 x 10(6) CD34+ cells/kg available for infusion received HDC. A median of 9.94 x 10(6) CD34+ cells/kg (range, 0.5 to 112.6 x 10(6) CD34+ cells/kg) contained in the PBPC collections was subsequently infused into patients after the administration of HDC. Engraftment was rapid with patients requiring a median of 9 days (range, 5 to 38 days) to achieve a neutrophil count of 0.5 x 10(9)/L and a median of 9 days (range, 4 to 53+ days) to achieve a platelet count of > or = 20 x 10(9)/L. A clear dose-response relationship was evident between the number of CD34+ cells per kilogram infused between the number of CD34+ cells per kilogram infused and neutrophil and platelet engraftment kinetics. Factors potentially influencing the engraftment kinetics of neutrophil and platelet recovery were examined using a Cox regression model. The single most powerful mediator of both platelet (P = .0001) and neutrophil (P = .0001) recovery was the CD34 content of the PBPC product. Administration of a post-PBPC infusion myeloid growth factor was also highly correlated with neutrophil recovery (P = .0001). Patients receiving high-dose cyclophosphamide, thiotepa, and carboplatin had more rapid platelet recovery than patients receiving other regimens (P = .006), and patients requiring 2 mobilization procedures versus 1 mobilization procedure to achieve > or = 2.5 x 10(6) CD34+ cells/kg experienced slower platelet recovery (P = .005). Although a minimal threshold CD34 dose could not be defined, > or = 5.0 x 10(6) CD34+ cells/kg appears to be optimal for ensuring rapid neutrophil and platelet recovery.

Single agent R115777, given at this dose and schedule, has an acceptable toxicity profile, but does not improve overall survival compared to best supportive care alone in refractory advanced CRC.

The farnesyl transferase inhibitor R115777 has demonstrated clinical activity in patients with metastatic breast cancer, and the ID regimen has a significantly improved therapeutic index compared with the CD regimen.

Using siRNA therapeutics to treat hematologic malignancies has been unsuccessful because blood cancer cells exhibit remarkable resistance to standard transfection methods. Herein, the successful delivery of siRNA therapeutics with a dual-targeted, layer-by-layer nanoparticle (LbL-NP) is reported. The LbL-NP protects siRNA from nucleases in the bloodstream by embedding it within polyelectrolyte layers that coat a polymeric core. The outermost layer consists of hyaluronic acid (a CD44-ligand) covalently conjugated to CD20 antibodies. The CD20/CD44 dual-targeting outer layer provides precise binding to blood cancer cells, followed by receptormediated endocytosis of the LbL-NP. This siRNA delivery platform is used to silence B-cell lymphoma 2 (BCL-2), a pro-survival protein, in vitro and in vivo. The dual-targeting approach significantly enhances internalization of BCL-2 siRNA in lymphoma and leukemia cells, which leads to significant downregulation of BCL-2 expression. Systemic administration of the dual-targeted, siRNA-loaded nanoparticle induces apoptosis and hampers proliferation of blood cancer cells, both in cell culture and in orthotopic non-Hodgkin's lymphoma animal models. These results provide the basis for approaches to targeting blood-borne cancers and other diseases and suggest that LbL nanoassemblies are a promising approach for delivering therapeutic siRNA to hematopoetic cell types that are known to evade transfection by other means.

Continuous dosing of R115777 is feasible with an acceptable toxicity profile at a dose of 300 mg bid.

A database of 327 patients with advanced Renal Cell Carcinoma (RCC) has been analyzed in order to identify potential baseline prognostic factors predicting for survival, following recombinant Interleukin-2 treatment (rIL-2). All patients received a continuous infusion (CIV). Eligibility criteria were uniform across studies, and included patients with an ambulatory performance status (PS), measurable disease, no CNS metastases, and no major organ compromise. Multivariate analyses identified baseline PS (ECOG 0 vs. 1), time from diagnosis to treatment (DTI greater than 24 months vs. less than or equal to 24 months), and the number of metastatic sites (1 vs. greater than or equal to 2, where lung, bone and other sites are considered as separate sites) as important predictors for survival. Patients can be classified into 4 subgroups, which are a function of the number of risk factors present. Median survival for each subgroup is 28, 17, 10 and 5 months, respectively. The model was validated in an independent cohort of 125 patients with RCC treated with subcutaneous (s/c) rIL-2, and predicted for survival accurately. By determining in which risk group category patients may fall, treating physicians may be better equipped to decide on patient management. The model may also be of value in order to stratify patients in randomized clinical trials.

No abstract

The purpose of this analysis was to compare the survival of patients with advanced renal carcinoma treated with intravenous recombinant interleukin-2 to the survival of matched patients taken from the large and well characterised database of the Eastern Cooperative Oncology Group (ECOG). Recombinant interleukin-2 (rIL-2) given by continuous intravenous infusion was used to treat 387 patients with advanced adenocarcinoma of the kidney in five multi-centre studies and 327 of these patients fulfilled the study eligibility criteria and were evaluable for response, toxicity and survival. The survival of patients treated with rIL-2 was compared in a multi-variate survival analysis taking account of all identified prognostic factors to 390 control patients receiving chemotherapy derived from the database. Thirteen patients treated with rIL-2 achieved a complete remission of their disease and 32 a partial remission giving an overall response rate of 14%. Remissions were durable with a median duration of 357 days for partial remissions and a median duration in excess of 926 days for complete remissions. Most patients experienced fever or mild to moderate hypotension and other toxicities are described. However, only 11 patients required admission to intensive care and in only five cases was this judged to be due to treatment toxicity. There were three deaths judged to be probably due to treatment toxicity. rIL-2 treatment was associated with significantly prolonged survival compared to the ECOG control patients. Patients with good prognostic features appeared to have a greater survival benefit from rIL-2 than those with poor prognostic features. This analysis provides the first evidence that rIL-2 prolongs survival in patients with advanced renal cancer but cannot provide proof which should be sought in randomised prospective trials drawing on the hypotheses generated herein.