Short telomeres are associated with inferior outcome, genomic complexity, and clonal evolution in chronic lymphocytic leukemia.

Telomere length in chronic lymphocytic leukemia (CLL) has been shown to be of prognostic importance, but the analyses have largely been executed on heterogeneous patient cohorts outside of clinical trials. In the present study, we performed a comprehensive analysis of telomere length associations in the well characterized CLL8 trial (n = 620) of the German CLL study group, with validation in a representative cohort of the CLL4 trial (n = 293). Absolute telomere length was analyzed using quantitative-PCR. Apart from identifying associations of short telomere length with adverse prognostic factors and survival, the study identified cases with 17p- and 11q- associated with TP53 and ATM loss, respectively, to have the shortest telomeres, even when these aberrations were present in small subclones. Thus, telomere shortening may precede acquisition of the high-risk aberrations, contributing to disease evolution. In line with this, telomere shortening was associated with an increase in genomic complexity as well as clonal evolution, highlighting its importance as a biomarker especially in monitoring disease progression in non-high-risk CLL.

PTK2 expression and immunochemotherapy outcome in chronic lymphocytic leukemia.

Addition of rituximab (R) to fludarabine and cyclophosphamide (FC) has significantly improved patient outcomes in chronic lymphocytic leukemia (CLL). Whether baseline gene expression can identify patients who will benefit from immunochemotherapy over chemotherapy alone has not been determined. We assessed genome-wide expression of 300 pretreatment specimens from a subset of 552 patients in REACH, a study of FC or R-FC in relapsed CLL. An independent test set was derived from 282 pretreatment specimens from CLL8, a study of FC or R-FC in treatment-naïve patients. Genes specific for benefit from R-FC were determined by assessing treatment-gene interactions in Cox proportional hazards models. REACH patients with higher pretreatment protein tyrosine kinase 2 (PTK2) messenger RNA levels derived greater benefit from R-FC, with significant improvements in progression-free survival, independent of known prognostic factors in a multivariate model. Examination of PTK2 gene expression in CLL8 patients yielded similar results. Furthermore, PTK2 inhibition blunted R-dependent cell death in vitro. This retrospective analysis from 2 independent trials revealed that increased PTK2 expression is associated with improved outcomes for CLL patients treated with R-FC vs FC. PTK2 expression may be a useful biomarker for patient selection in future trials. These trials were registered at www.clinicaltrials.gov as #NCT00090051 (REACH) and #NCT00281918 (CLL8).

Gene mutations and treatment outcome in chronic lymphocytic leukemia: results from the CLL8 trial.

Mutations in TP53, NOTCH1, and SF3B1 were analyzed in the CLL8 study evaluating first-line therapy with fludarabine and cyclophosphamide (FC) or FC with rituximab (FCR) among patients with untreated chronic lymphocytic leukemia (CLL). TP53, NOTCH1, and SF3B1 were mutated in 11.5%, 10.0%, and 18.4% of patients, respectively. NOTCH1(mut) and SF3B1(mut) virtually showed mutual exclusivity (0.6% concurrence), but TP53(mut) was frequently found in NOTCH1(mut) (16.1%) and in SF3B1(mut) (14.0%) patients. There were few significant associations with clinical and laboratory characteristics, but genetic markers had a strong influence on response and survival. In multivariable analyses, an independent prognostic impact was found for FCR, thymidine kinase (TK) ≥10 U/L, unmutated IGHV, 11q deletion, 17p deletion, TP53(mut), and SF3B1(mut) on progression-free survival; and for FCR, age ≥65 years, Eastern Cooperative Oncology Group performance status ≥1, ß2-microglobulin ≥3.5 mg/L, TK ≥10 U/L, unmutated IGHV, 17p deletion, and TP53(mut) on overall survival. Notably, predictive marker analysis identified an interaction of NOTCH1 mutational status and treatment in that rituximab failed to improve response and survival in patients with NOTCH1(mut). In conclusion, TP53 and SF3B1 mutations appear among the strongest prognostic markers in CLL patients receiving current-standard first-line therapy. NOTCH1(mut) was identified as a predictive marker for decreased benefit from the addition of rituximab to FC. This study is registered at www.clinicaltrials.gov as #NCT00281918.

Effect of FCGR2A and FCGR3A variants on CLL outcome.

Polymorphisms of activating Fc-γ receptors (FCGRs) on natural killer cells and macrophages result in variable affinity for immunoglobulin G1 monoclonal antibodies and subsequently modulate antibody-dependent cellular cytotoxicity (ADCC) activity. Whether single-nucleotide polymorphisms of FCGRs correlate with survival of chronic lymphocytic leukemia (CLL) patients treated with a monoclonal antibody containing regimen is unclear. We assessed the FCGR3A and FCGR2A genotype of patients enrolled in the REACH trial, where patients received fludarabine and cyclophosphamide (FC) or rituximab plus FC (R-FC). FCGR3A and FCGR2A polymorphisms did not demonstrate prognostic significance in the FC arm (P = .42 and P = .64, respectively) or R-FC arm (P = .41 and P = .88, respectively) with respect to progression free survival. Patients with intermediate affinity genotypes (FV and HR) benefited significantly from addition of rituximab (hazard ratio = 0.55 [0.37-0.8 CI]; P = .0017 and hazard ratio = 0.63 [0.44-0.9 CI]; P = .011, respectively). Similar benefit was suggested for patients with high- affinity VV and HH (hazard ratio = 0.86 [0.4-1.84 CI]; P = .7 and hazard ratio = 0.7 [0.41-1.18 CI]; P = .18, respectively) and low-affinity FF and RR (hazard ratio = 0.85 [0.56-1.29 CI]; P = .44 and hazard ratio = 0.82 [0.47-1.42 CI]; P = .48, respectively). Overall, our results suggest that FCGR2A and FCGR3A polymorphisms do not significantly influence the outcomes of relapsed or refractory CLL patients treated with FC or the monoclonal antibody regimen R-FC.

Modeling and Estimating Recall Processing Capacity: Sensitivity and Diagnostic Utility in Application to Mild Cognitive Impairment.

We investigate the potential for using latency-based measures of retrieval processing capacity to assess changes in perfomance specific to individuals with mild cognitive impairment (MCI), a reliable precursor state to Alzheimer's Disease. Use of these capacity measures is motivated in part by exploration of the effects of atrophy on a computational model of a basic hippocampal circuit. We use this model to suggest that capacity may be a more sensitive indicator of undelying atrophy than speed of processing, and test this hypothesis by adapting a standard behavioral measure of memory (the free and cued selective reminding test, FCSRT) to allow for the collection of cued recall latencies. Participants were drawn from five groups: college-aged, middle-aged, healthy elderly, those with a diagnosis of MCI, and a sample of MCI control participants. The measure of capacity is shown to offer increased classificatory sensitivity relative to the standard behavioral measures, and is also shown to be the behavioral measure that correlated most strongly with hippocampal volume.

Rituximab plus fludarabine and cyclophosphamide prolongs progression-free survival compared with fludarabine and cyclophosphamide alone in previously treated chronic lymphocytic leukemia.

PURPOSE: Rituximab, a monoclonal antibody that targets the CD20 cell surface antigen, has clinical activity in patients with non-Hodgkin's lymphoma and other B-lymphocyte disorders when administered alone or in combination with chemotherapy. Promising results have previously been reported in nonrandomized studies in patients with chronic lymphocytic leukemia (CLL). This trial was designed to compare chemoimmunotherapy with chemotherapy alone in patients with previously treated CLL. PATIENTS AND METHODS: This international, multicenter, randomized trial compared six cycles of rituximab plus fludarabine and cyclophosphamide (R-FC) with six cycles of fludarabine and cyclophosphamide alone (FC) in patients with previously treated CLL. A total of 552 patients with Binet stage A (1%), B (59%), or C (31%) disease entered the study and were randomly assigned to receive R-FC (n = 276) or FC (n = 276). RESULTS: After a median follow-up time of 25 months, rituximab significantly improved progression-free survival in patients with previously treated CLL (hazard ratio = 0.65; P < .001; median, 30.6 months for R-FC v 20.6 months for FC). Event-free survival, response rate, complete response rate, duration of response, and time to new CLL treatment or death were also significantly improved. Although the rates of adverse events, grade 3 or 4 events, and serious adverse events were slightly higher in the R-FC arm, R-FC was generally well tolerated, with no new safety findings and no detrimental effect on quality of life. CONCLUSION: R-FC significantly improved the outcome of patients with previously treated CLL.

Gender associations with chronic methylphenidate treatment and behavioral performance following experimental traumatic brain injury.

Evidence suggests that dopamine (DA) agonists improve cognition after traumatic brain injury (TBI). Methylphenidate (MPH) is a DA agonist that blocks the dopamine transporter (DAT). Moreover, female sex hormones modulate DAT expression. Therefore, the purpose of this study was to evaluate how MPH affects behavioral performance in male and female rats. Under anesthesia, rats underwent either controlled cortical impact (CCI) or sham injury operations. Beginning post-operative day 1, rats received daily intraperitoneal injections of MPH (5mg/kg) or saline. Beam balance (BB) and beam-walking (BW) were assessed on post-operative days 1-5. Exploratory behavior was assessed using an open field free choice novelty (FCN) task on day 13. Spatial memory was assessed with a Morris water maze (MWM) task on days 14-20. Multivariate analyses showed TBI females performed better than TBI males on both motor tasks (P<0.05 both comparisons), and MPH improved BB performance for both male and female injury groups (P=0.05) compared to their respective vehicle treated injury groups. Multivariate analysis showed that MPH enhanced MWM performance (spatial learning and retention) after TBI. Significant improvements were noted only in injured males treated with MPH compared to their vehicle control (P<0.05) with respect to improvements in memory acquisition and retention. Further, injured females treated with MPH had faster swimming speeds than all other groups (P<0.05 all comparisons), and MPH increased activity in TBI females but not males in the FCN task (P<0.05). These results suggest that MPH is beneficial after TBI. However there are gender specific drug differences in behavioral performance and sensitivity to treatment with MPH that may have implications for treatment efficacy and dosing clinically after TBI.

The effects of rituximab treatment during pregnancy on a neonate.

A 35-year old woman developed Burkitt's lymphoma and was treated with rituximab and CHOP therapy early during pregnancy. Monitoring of rituximab concentrations and B-cell counts in the child revealed a transient complete B-cell depletion associated with high rituximab cord blood concentrations. B-cell recovery was fast, showing a regular immunophenotype without loss of CD20 antigen, no functional deficits and adequate vaccination IgG titers.

Evaluation of estrous cycle stage and gender on behavioral outcome after experimental traumatic brain injury.

Female sex hormones are acutely neuroprotective in experimental models of traumatic brain injury (TBI). Because hormonal profiles are known to vary with estrous cycle stage, the purpose of this study was to evaluate how pre-injury estrous stage affects motor and cognitive performance after experimental TBI. We also sought to compare post-injury behavioral performance in males vs. females. Under anesthesia, male (n=18) and female (n=35) Sprague-Dawley rats underwent either controlled cortical impact (CCI) injury (2.7 mm; 4 m/s) or sham operations. Females were grouped according to estrous stage (proestrous or non-proestrous) at the time of surgery. Motor function was assessed pre-injury and for the first 5 days after surgery using beam balance and walking tasks. Spatial memory was assessed beginning 14 days post-injury utilizing the Morris water maze (MWM) task. No significant differences were found on any task between injured females regardless of estrous cycle stage. Females performed significantly better than males on both motor tasks, but gender did not influence MWM performance. Mixed effects multivariate analysis corroborated these results by showing that pre-injury serum hormone levels had little affect on behavioral performance. The results suggest that the presence of endogenous circulating hormones, rather than hormonal status at time of injury, may confer early neuroprotection in females after TBI. The impact of early neuroprotection on later behavioral outcome and the anatomic structural specificity of hormonal neuroprotection require further study.