Reed, John C.

Purpose Genomic features including unmutated immunoglobulin variable region heavy chain (IgV H ) genes, del(11q22.3), del(17p13.1), and p53 mutations have been reported to predict the clinical course and overall survival of patients with chronic lymphocytic leukemia (CLL). In addition, ZAP-70 and Bcl-2 family proteins have been explored as predictors of outcome. Patients and Methods We prospectively evaluated the prognostic significance of a comprehensive panel of laboratory factors on both response and progression-free survival (PFS) using samples and data from 235 patients enrolled onto a therapeutic trial. Patients received either fludarabine (FL; n = 113) or fludarabine plus cyclophosphamide (FC; n = 122) as part of a US Intergroup randomized trial for previously untreated CLL patients. Results Complete response (CR) rates were 24.6% for patients receiving FC and 5.3% for patients receiving FL (P = .00004). PFS was statistically significantly longer in patients receiving FC (median, 33.5 months for patients receiving FC and 19.9 months for patients receiving FL; P < .0001). The occurrence of del(17p13.1) (hazard ratio, 3.428; P = .0002) or del(11q22.3) (hazard ratio, 1.904; P = .006) was associated with reduced PFS. CR and overall response rates were not significantly different based on cytogenetics, IgV H mutational status, CD38 expression, or p53 mutational status. Expression of ZAP-70, Bcl-2, Bax, Mcl-1, XIAP, Caspase-3, and Traf-1 was not associated with either clinical response or PFS. Conclusion These results support the use of interphase cytogenetic analysis, but not IgV H , CD38 expression, or ZAP-70 status, to predict outcome of FL-based chemotherapy. Patients with high-risk cytogenetic features should be considered for alternative therapies.

Abstract Purpose: According to some studies, susceptibility of cells to anticancer drug-induced apoptosis is markedly inhibited by targeted deletion of genes encoding apoptotic protease activating factor 1 (Apaf-1) or certain caspases. Information about levels of these polypeptides in common cancer cell types and any possible correlation with drug sensitivity in the absence of gene deletion is currently fragmentary. Experimental Design: Immunoblotting was used to estimate levels of Apaf-1 as well as procaspase-2, -3, -6, -7, -8, and -9 in the 60-cell-line panel used for drug screening by the National Cancer Institute. Sensitivity of the same lines to &gt;80,000 compounds was determined with 48-hour sulforhodamine B binding assays. Additional 6-day assays were performed for selected agents. Results: Levels of Apaf-1 and procaspases varied widely. Apaf-1 and procaspase-9, which are implicated in caspase activation after treatment of cells with various anticancer drugs, were detectable in all of the cell lines, with levels of Apaf-1 ranging from ∼1 × 105 to 2 × 106 molecules per cell and procaspase-9 from ∼5 × 103 to ∼1.6 × 105 molecules per cell. Procaspase-8 levels ranged from 1.7 × 105 to 8 × 106 molecules per cell. Procaspase-3, a major effector caspase, varied from undetectable to ∼1.6 × 106 molecules per cell. Correlations between levels of these polypeptides and sensitivity to any of a variety of experimental or conventional antineoplastic agents in either 2-day or 6-day cytotoxicity assays were weak at best. Conclusions: With the exception of caspase-3, all of the components of the core cell-death machinery are expressed in all of the cell lines examined. Despite variations in expression, levels of any one component are not a major determinant of drug sensitivity in these cells in vitro.