PGC-1alpha genotype modifies the association of volitional energy expenditure with VO2max

To further our understanding about antigen involvement in mantle cell lymphoma (MCL), we analyzed the expression levels of activation-induced cytidine deaminase (AID), a key player in B-cell responses to antigen triggering, in 133 MCL cases; assessed the functionality of AID by evaluating in vivo class switch recombination in 52 MCL cases; and sought for indications of ongoing antigen interactions by exploring intraclonal diversification within 14 MCL cases. The AID full-length transcript and the most frequent splice variants (AID-DeltaE4a, AID-DeltaE) were detected in 128 (96.2%), 96 (72.2%), and 130 cases (97.7%), respectively. Higher AID full-length transcript levels were significantly associated (P < 0.001) with lack of somatic hypermutation within the clonotypic immunoglobulin heavy variable (IGHV) genes. Median AID transcript levels were higher in lymph node material compared to cases in which peripheral blood was analyzed, implying that clonal behavior is influenced by the microenvironment. Switched tumor-derived IGHV-IGHD-IGHJ transcripts were identified in 5 of 52 cases (9.6%), all of which displayed somatic hypermutation and AID-mRNA expression. Finally, although most cases exhibited low levels of intraclonal diversification, analysis of the mutational activity revealed a precise targeting of somatic hypermutation indicative of an active, ongoing interaction with antigen(s). Collectively, these findings strongly allude to antigen involvement in the natural history of MCL, further challenging the notion of antigen naivety

Not all IGHV3-21 chronic lymphocytic leukemias are equal: Prognostic considerations

An unresolved issue in chronic lymphocytic leukemia (CLL) is whether IGHV3-21 gene usage, in general, or the expression of stereotyped B-cell receptor immunoglobulin defining subset #2 (IGHV3-21/IGLV3-21), in particular, determines outcome for IGHV3-21-utilizing cases. We reappraised this issue in 8593 CLL patients of whom 437 (5%) used the IGHV3-21 gene with 254/437 (58%) classified as subset #2.Within subset #2, immunoglobulin heavy variable (IGHV)-mutated cases predominated, whereas non-subset #2/IGHV3-21 was enriched for IGHV-unmutated cases (P = .002). Subset #2 exhibited significantly shorter time-to-first-treatment (TTFT) compared with non-subset #2/IGHV3-21 (22 vs 60 months, P = .001). No such difference was observed between non-subset #2/IGHV3-21 vs the remaining CLL with similar IGHV mutational status. In conclusion, IGHV3-21 CLL should not be axiomatically considered a homogeneous entity with adverse prognosis, given that only subset #2 emerges as uniformly aggressive, contrasting non-subset #2/IGVH3-21 patients whose prognosis depends on IGHV mutational status as the remaining CLL. © 2015 by The American Society of Hematology 10.1182/blood-2014-09-600874

Clinical effect of stereotyped B-cell receptor immunoglobulins in chronic lymphocytic leukaemia: A retrospective multicentre study

Background: About 30% of cases of chronic lymphocytic leukaemia (CLL) carry quasi-identical B-cell receptorimmunoglobulins and can be assigned to distinct stereotyped subsets. Although preliminary evidence suggeststhat B-cell receptor immunoglobulin stereotypy is relevant from a clinical viewpoint, this aspect has never beenexplored in a systematic manner or in a cohort of adequate size that would enable clinical conclusions to be drawn.Methods: For this retrospective, multicentre study, we analysed 8593 patients with CLL for whom immunogeneticdata were available. These patients were followed up in 15 academic institutions throughout Europe (in CzechRepublic, Denmark, France, Greece, Italy, Netherlands, Sweden, and the UK) and the USA, and data were collectedbetween June 1, 2012, and June 7, 2013. We retrospectively assessed the clinical implications of CLL B-cell receptorimmunoglobulin stereotypy, with a particular focus on 14 major stereotyped subsets comprising cases expressingunmutated (U-CLL) or mutated (M-CLL) immunoglobulin heavy chain variable genes. The primary outcome ofour analysis was time to fi rst treatment, defi ned as the time between diagnosis and date of fi rst treatment.Findings: 2878 patients were assigned to a stereotyped subset, of which 1122 patients belonged to one of 14 majorsubsets. Stereotyped subsets showed signifi cant diff erences in terms of age, sex, disease burden at diagnosis,CD38 expression, and cytogenetic aberrations of prognostic signifi cance. Patients within a specifi c subset generallyfollowed the same clinical course, whereas patients in diff erent stereotyped subsets-despite having the sameimmunoglobulin heavy variable gene and displaying similar immunoglobulin mutational status-showedsubstantially diff erent times to fi rst treatment. By integrating B-cell receptor immunoglobulin stereotypy (forsubsets 1, 2, and 4) into the well established Döhner cytogenetic prognostic model, we showed these, whichcollectively account for around 7% of all cases of CLL and represent both U-CLL and M-CLL, constituted separateclinical entities, ranging from very indolent (subset 4) to aggressive disease (subsets 1 and 2).Interpretation: The molecular classifi cation of chronic lymphocytic leukaemia based on B-cell receptorimmunoglobulin stereotypy improves the Döhner hierarchical model and refi nes prognostication beyondimmunoglobulin mutational status, with potential implications for clinical decision making, especially withinprospective clinical trials