No abstract

SUMMARY Background Diffuse large-B-cell lymphoma (DLBCL) is curable but when treatment fails, outcome is poor. Imaging scans help identify patients at risk of treatment failure but are often imprecise, and the radiation exposure is a potential health risk. Specific, sensitive and readily available biomarkers of treatment failure are needed. Methods We retrospectively analyzed cell-free circulating tumor DNA (ctDNA) in patients treated on one of 3 treatment protocols using quantitative next-generation DNA sequencing. Eligible patients had DLBCL, no evidence of indolent lymphoma and were previously untreated. Serial serum samples and concurrent computed tomography scans were obtained at specified times during most treatment cycles and 5-years of follow-up. VDJ gene segments of the rearranged immunoglobulin receptor genes were amplified and sequenced from pre-treatment specimens and serum ctDNA encoding the VDJ rearrangements was quantitated. Findings Tumor clonotype(s) were identified in pretreatment specimens from 126 patients who were followed for a median (interquartile range) of 11 (6.8 to 14.2) years. Interim ctDNA monitoring at the end of 2 treatment cycles in 108 patients showed a time to progression (TTP) of 41.7% (95% Confidence Interval (CI): 22.2% to 60.1%) and 80.2% (95% CI: 69.6% to 87.3%), at 5-years (p<0.0001) in patients with and without detectable ctDNA, respectively, and a positive and negative predicative value (PPV and NPV) of 63% and 80%, respectively. Surveillance ctDNA monitoring was performed in 107 patients who achieved complete remission. A Cox proportional hazards model showed patients who developed detectable ctDNA during surveillance had a hazard ratio 228 times that of patients with undetectable ctDNA for clinical disease progression (95% CI: 51 to 1022) (p<0.0001). Surveillance ctDNA had a PPV and NPV of 88% and 98%, respectively, and identified recurrence a median (range) of 3.5 months (0 to 200) before evidence of clinical disease. Interpretation Surveillance ctDNA identifies patients at risk of recurrence before clinical evidence of disease in most patients and results in lower disease burden at relapse. Interim ctDNA is a promising biomarker to identify patients at high risk of treatment failure.

1 Mitochondrial proton F0F1-ATPase/ATP synthase synthesizes ATP during oxidative phosphorylation. In this study, we examined the eects of several groups of polyphenolic phytochemicals on the activity of the enzyme. 2 Resveratrol, a stilbene phytoalexin that is present in grapes and red wine, concentrationdependently inhibited the enzymatic activity of both rat brain and liver F0F1-ATPase/ATP synthase (IC 50 of 12 ± 28 mM). 3 Screening of other polyphenolic phytochemicals using rat brain F0F1-ATPase activity resulted in the following ranking potency (IC 50 in parenthesis): piceatannol (8 mM)4resveratrol (19 mM)= (7)epigallocatechin gallate (17 mM)4(7)epicatechin gallate, curcumin (45 mM)4genistein=biocha-nin A=quercetin=kaempferol=morin (55 ± 65 mM)4phloretin=apigenin=daidzein (approx. 100 mM). Genistin, quercitrin, phloridzin, (+)catechin, (+)epicatechin, (7)epicatechin and (7)epigallocatechin had little eect at similar concentrations. Tannic acid, thea¯avins (tea extract) and grape seed proanthocyanidin extract (GSPE) had IC 50 values of 5, 20 and 30 mg ml 71 , respectively. Several monophenolic antioxidants and non-phenolic compounds were ineective at concentrations of 210 mM or higher. 4 The inhibition of F0F1-ATPase by resveratrol and genistein was non-competitive in nature. 5 The eects of polyphenolic phytochemicals were additive. 6 Both resveratrol and genistein had little eect on the Na + /K + -ATPase activity of porcine cerebral cortex, whereas quercetin had similar inhibitory potency as for F0F1-ATPase. 7 In conclusion, the ATP synthase is a target for dietary phytochemicals. This pharmacological property of these phytochemicals should be included in the examination of their health bene®ts as well as potential cytotoxicity.

The persistence of minimal residual disease (MRD) during therapy is the strongest adverse prognostic factor in acute lymphoblastic leukemia (ALL). We developed a high-throughput sequencing method that universally amplifies antigenreceptor gene segments and identifies all clonal gene rearrangements (ie, leukemiaspecific sequences) at diagnosis, allowing monitoring of disease progression and clonal evolution during therapy. In the present study, the assay specifically detected 1 leukemic cell among greater than 1 million leukocytes in spike-in experiments. We compared this method with the gold-standard MRD assays multiparameter flow cytometry and allele-specific oligonucleotide polymerase chain reaction (

In this study, we compared immunoglobulin heavy-chain-gene-based minimal residual disease (MRD) detection by real-time quantitative PCR (RQ-PCR) and next-generation sequencing (NGS) to assess whether NGS could overcome some limitations of RQ-PCR and further increase sensitivity, specificity, accuracy and reproducibility. In total, 378 samples from 55 patients with acute lymphoblastic leukemia (ALL), mantle cell lymphoma (MCL) or multiple myeloma (MM) were investigated for clonotype identification, clonotype identity and comparability of MRD results. Forty-five clonotypes were identified by RQ-PCR and 49 by NGS. Clonotypes identified by both tools were identical or >97% homologous in 96% of cases. Both tools were able to routinely reach a sensitivity level of 1 × E-05. A good correlation of MRD results was observed (R=0.791, P<0.001), with excellent concordance in 79.6% of cases. Few discordant cases were observed across all disease subtypes. NGS showed at least the same level of sensitivity as allele-specific oligonucleotides-PCR, without the need for patient-specific reagents. We conclude that NGS is an effective tool for MRD monitoring in ALL, MCL and MM. Prospective comparative analysis of unselected cases is required to validate the clinical impact of NGS-based MRD assessment.