Ipilimumab in combination with paclitaxel and carboplatin as first-line therapy in extensive-disease-small-cell lung cancer: results from a randomized, double-blind, multicenter phase 2 trial.

BACKGROUND: Ipilimumab, an anti-CTLA4 monoclonal antibody, demonstrated survival benefit in melanoma with immune-related (ir) adverse events (irAEs) managed by the protocol-defined guidelines. This phase 2 study evaluated ipilimumab+paclitaxel (Taxol)/carboplatin in extensive-disease-small-cell lung cancer (ED-SCLC). DESIGN: Patients (n=130) with chemotherapy-naïve ED-SCLC were randomized 1: 1: 1 to receive paclitaxel (175 mg/m2)/carboplatin (area under the curve=6) with either placebo (control) or ipilimumab 10 mg/kg in two alternative regimens, concurrent ipilimumab (ipilimumab+paclitaxel/carboplatin followed by placebo+paclitaxel/carboplatin) or phased ipilimumab (placebo+paclitaxel/carboplatin followed by ipilimumab+paclitaxel/carboplatin). Treatment was administered every 3 weeks for a maximum of 18 weeks (induction), followed by maintenance ipilimumab or placebo every 12 weeks. End points included progression-free survival (PFS), irPFS, best overall response rate (BORR); irBORR, overall survival (OS), and safety. RESULTS: Phased ipilimumab, but not concurrent ipilimumab, improved irPFS versus control [HR (hazard ratio)=0.64; P=0.03]. No improvement in PFS (HR=0.93; P=0.37) or OS (HR=0.75; P=0.13) occurred. Phased ipilimumab, concurrent ipilimumab and control, respectively, were associated with median irPFS of 6.4, 5.7 and 5.3 months; median PFS of 5.2, 3.9 and 5.2 months; median OS of 12.9, 9.1 and 9.9 months. Overall rates of grade 3/4 irAEs were 17, 21 and 9% for phased ipilimumab, concurrent ipilimumab and control, respectively. CONCLUSION: These results suggest further investigation of ipilimumab in ED-SCLC.

Peptide containing the BCR oligomerization domain (AA 1-160) reverses the transformed phenotype of p210bcr-abl positive 32D myeloid leukemia cells.

We first showed that the introduction of a bcr-abl transcription unit into the 32D murine myeloid cell line (P210bcrabl32D) converts this cell line from an IL3 dependent cell line to an IL3 growth independent cell line. We next cloned a fragment of the bcr-abl cDNA, which codes for the bcr oligomerization domain and neighboring regions. To test for a transformation inhibitory effect of this oligomerization inhibitory peptide transcription unit on the p210bcr-abl mediated IL3 independent growth of the P210bcrabl32D cell line, we transiently co-electroporated into the growth factor dependent 32D cells, mixtures of plasmids which contained varying ratios of the plasmid expression vectors for the bcr oligomerization inhibitory peptide along with a smaller amount of the plasmid expression vector for the full length p210bcr-abl. (The P210bcr-abl protein converts the 32D from a growth factor dependent into a growth factor independent cell line.) We then showed that the oligomerization domain containing fragment from the bcr and bcr-abl proteins, can be used to inhibit the IL3 independent growth of p210bcr-abl positive 32D cells. These studies may be of eventual interest for those investigators whose goal is to design molecular therapeutic approaches to CML based on the use of peptidomimetic chemical functionalities, which mimic the structure and the inhibitory binding properties of the oligomerization domain containing fragment so as to inhibit the transforming function of the P210bcr-abl oncoprotein.

N-acetylcysteine protects lymphocytes from nitrogen mustard-induced apoptosis.

The ability of the antioxidant N-acetylcysteine to prevent apoptosis induced in lymphocytes by nitrogen mustard (HN2) was investigated. HN2 caused a concentration-dependent induction of apoptosis on C3H murine spleen cells, as identified by two criteria: morphological features revealed by microscopical observations and DNA fragmentation visualized by the characteristic "ladder" pattern observed upon agarose gel electrophoresis, as well as by hypodiploid DNA-containing cells revealed by the flow cytometric analysis of propidium iodide labelled cells. The antioxidant N-acetylcysteine (NAC) was found to markedly reduce the occurrence of HN2-induced apoptosis in these cells. This protective effect will still obtained when NAC was added 30 min after HN2. In contrast, the pretreatment of spleen cells with this antioxidant did not provide any significant protection. We also showed that lymphocytes protected by NAC are still able to respond to a mitogenic stimulation. To gain some insight into the mechanisms underlying the cytoprotective action of NAC against HN2, we tested whether or not poly(ADP-ribose) polymerase (PARP, EC 2.4.2.30), a nuclear enzyme that participates in the triggering of apoptosis induced by alkylating agents, is involved. We report that 6(5H)-phenanthridinone, a potent PARP inhibitor, did not affect the ability of NAC to prevent HN2-induced apoptosis under our experimental conditions. Thus, the exact mechanism by which NAC protects lymphocytes from HN2 cytotoxicity has yet to be determined.

Positive selection of CD34+ cells from cryopreserved peripheral blood stem cells after thawing: technical aspects and clinical use.

Autologous stem cell transplantation has become an important therapy in lymphoma, multiple myeloma and solid tumors. The rationale for the selection of CD34+ cells from peripheral blood or bone marrow progenitor cell collections is based on the observation that contaminating tumor cells can be depleted approximately 3 to 6 logs. This procedure may be limited because of lack of sufficient numbers of progenitor cells in the leukapheresis concentrates. The use of frozen/thawed peripheral blood mononuclear cell (PBMC) samples makes it possible to pool two or even more stem cell harvests collected at different time points to increase the total number of CD34+ progenitor cells. We report in this work the feasibility of frozen/thawed peripheral blood CD34+ positive cell selection, using the large-scale (Ceprate SC) and the lab-scale avidin-biotin immunoadsorption system (Ceprate LC). This procedure consists of a washing step and a positive selection step. Our results show that frozen/thawed CD34+ cells were obtained with a purity of 86.68 +/- 3.62%, a viability of 97.94 +/- 0.97% and a recovery of 91.85 +/- 10.84% (range 80 to 112%). The CFU-GM assays were performed in a methylcellulose based medium; 89.13 +/- 19.63 colonies were obtained for 10(3) cells plated. Two patients were grafted with peripheral blood CD34+ cells selected after freezing. Our clinical data show that these cells are capable of rapidly reconstituting hematopoiesis after high-dose chemotherapy.

Peripheral blood CD34+ cells: method of purification and ex vivo expansion.

Peripheral blood stem cells (PBSC) are used increasingly for autotransplantation in the treatment of acute leukemia, lymphoma, multiple myeloma, solid tumors such as ovarian and breast carcinoma. They are collected by leukaphereses during rapid hematopoietic recovery, following cytotoxic chemotherapy with or without administration of hematopoietic growth factors. We studied the clonogenic and cytokine-mediated expansion potential of CD34+ cells from mobilized PBSC. Low density mononuclear cells were processed using the CEPRATE LC CD34 KIT (CellPro). CD34+ purified cells, were cultured in suspension with 6 combined hematopoietic growth factors (IL1beta, IL3, IL6 at 100 U/ml and G-CSF, GM-CSF and stem cell factor at 10 ng/ml of each) for up to four weeks. Every week, cells were counted and CFU-GM assay was performed in a methylcellulose based medium. We have analysed the percentage of cells bearing CD34, CD33, CD38, HLA-DR, CD45RA, CD45RO antigens. Our results showed, that CD34+ cells were obtained with a purity of 92 +/- 2.3% and a yield of 71 +/- 10.7%. The majority co-expressed CD33 (57.76 +/- 34.16%) and CD38 (62.2 +/- 34%) antigens. These culture conditions, are necessary to obtain a fold increase of nucleated cells (377 fold at week 4), of CFU-GM progenitors (41.2 fold at week 3) and of CD34+ cell absolute number (10 fold at week 1) with an important differentiation of progenitors in particular myeloid progenitors.