Fludarabine plus alemtuzumab versus fludarabine alone in patients with previously treated chronic lymphocytic leukaemia: a randomised phase 3 trial

Background Chronic lymphocytic leukaemia (CLL) is an incurable and chronic disorder, with worsening prognosis for patients as their disease progresses. We compared the efficacy and safety of the combination of fludarabine and alemtuzumab with fludarabine monotherapy in previously treated patients with relapsed or refractory CLL. Methods Patients (aged >= 18 years) with CLL Binet stage A, B, or C or Rai stages I-IV were randomly assigned in a 1: 1 ratio according to a computer-generated allocation schedule to open-label combination treatment (fludarabine 30 mg/m(2) per day and alemtuzumab 30 mg per day on days 1-3) or monotherapy (fludarabine 25 mg/m(2) on days 1-5) by use of an interactive voice response system. Both regimens were given intravenously for a maximum of six 28-day cycles. The primary endpoint was progression-free survival (PFS). Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00086580. Findings Fludarabine plus alemtuzumab (n=168) resulted in better PFS than did fludarabine monotherapy (n=167; median 23.7 months [95% CI 19.2-28.4] vs 16.5 months [12.5-21.2]; hazard ratio 0.61 [95% CI 0.47-0.80]; p=0.0003) and overall survival (median not reached vs 52.9 months [40.9-not reached]; 0.65 [0.45-0.94]; p=0.021) compared with fludarabine alone. All-cause adverse events occurred in 161 (98%) of 164 patients in the combination treatment group and 149 (90%) of 165 in the fludarabine alone group. Patients in the fludarabine plus alemtuzumab group had more cytomegalovirus events (23 [14%] vs one [<1%]) and grade 1 or 2 potentially alemtuzumab infusion-related adverse reactions (102 [62%] vs 22 [13%]). Grade 3 or 4 toxicities in the combination treatment and monotherapy groups were leucopenia (121 [74%] of 164 vs 55 [34%] of 164), lymphopenia (149 [94%] of 158 vs 53 [33%] of 161), neutropenia (93 [59%] of 157 vs 110 [68%] of 161), thrombocytopenia (18 [11%] of 164 vs 27 [17%] of 163), and anaemia (14 [9%] of 163 vs 28 [17%] of 164). The incidence of serious adverse events was higher in the combination treatment group (54 [33%] of 164 vs 41 [25%] of 165); deaths due to adverse events were similar between the two groups (ten [6%] vs 12 [7%]). Interpretation The combination of fludarabine and alemtuzumab is another treatment option for patients with previously treated CLL

Influence of hyaluronic acid synthesis and cumulus mucification on bovine oocyte in vitro maturation, fertilisation and embryo development

© CSIRO 2007During cumulus–oocyte complex (COC) maturation, cumulus expansion involves the deposition of mucoelastic compounds, especially hyaluronic acid, synthesised from glucose via the hexosamine biosynthesis pathway. The aim of the present study was to determine the effects of uridine monophosphate (UMP) and 6-diazo-5-oxo-l-norleucine (DON), inhibitors of hyaluronic acid synthesis, during bovine oocyte in vitro maturation (IVM) on cumulus expansion, glucose uptake, protein synthesis, cumulus cell number, meiotic maturation, cleavage rate and subsequent embryo development. A further aim of the study was to examine the effect of hyaluronic acid on sperm capacitation and acrosome reaction in relation to the capacity of COCs to be fertilised in vitro. A low correlation between glucose uptake and degree of cumulus expansion was observed. Total and partial inhibition of cumulus expansion was observed with DON and UMP, respectively, and was accompanied by a decrease in glucose uptake with DON. Total protein content and cumulus cell number per COC increased during IVM, but was unaffected by the presence of DON or UMP, as was oocyte meiotic maturation. Rates of cleavage and blastocyst development decreased in oocytes matured with DON and UMP, although this inhibition was reversed when the in vitro fertilisation (IVF) medium contained heparin. Hyaluronic acid induced capacitation and the acrosome reaction, and in IVF medium prevented the inhibition of cleavage and blastocyst development by DON in a similar fashion to heparin. Hyaluronic acid synthesis during cumulus mucification contributes to the penetration and fertilisation of bovine oocytes, most likely by facilitating the processes of capacitation and acrosome reaction. Mucification during IVM is independent of cumulus cell proliferation, COC protein content, oocyte meiotic maturation and subsequent developmental competence once fertilised.Cynthia Gutnisky, Gabriel C. Dalvit, Laura N. Pintos, Jeremy G. Thompson, Martha T. Beconi and Pablo D. Cetic

Dickkopf-1 Can Lead to Immune Evasion in Metastatic Castration-Resistant Prostate Cancer

PURPOSE Metastatic castration-resistant prostate cancer (mCRPC) with low androgen receptor (AR) and without neuroendocrine signaling, termed double-negative prostate cancer (DNPC), is increasingly prevalent in patients treated with AR signaling inhibitors and is in need of new biomarkers and therapeutic targets. METHODS Candidate genes enriched in DNPC were determined using differential gene expression analysis of discovery and validation cohorts of mCRPC biopsies. Laboratory studies were carried out in human mCRPC organoid cultures, prostate cancer (PCa) cell lines, and mouse xenograft models. Epigenetic studies were carried out in a rapid autopsy cohort. RESULTS Dickkopf-1 (DKK1) expression is increased in DNPC relative to prostate-specific antigen (PSA)–expressing mCRPC in the Stand Up to Cancer/Prostate Cancer Foundation discovery cohort (11.2 v 0.28 reads per kilobase per million mapped reads; q < 0.05; n = 117) and in the University of Washington/Fred Hutchinson Cancer Research Center cohort (9.2 v 0.99 fragments per kilobase of transcript per million mapped reads; P < .0001). DKK1 expression can be regulated by activated Wnt signaling in vitro and correlates with activating canonical Wnt signaling mutations and low PSA mRNA in mCRPC biopsies ( P < .05). DKK1 hypomethylation was associated with increased DKK1 mRNA expression (Pearson r = −0.66; P < .0001) in a rapid autopsy cohort (n = 7). DKK1-high mCRPC biopsies are infiltrated with significantly higher numbers of quiescent natural killer (NK) cells ( P < .005) and lower numbers of activated NK cells ( P < .0005). Growth inhibition of the human PCa model PC3 by the anti-DKK1 monoclonal antibody DKN-01 depends on the presence of NK cells in a severe combined immunodeficient xenograft mouse model. CONCLUSION These results support DKK1 as a contributor to the immunosuppressive tumor microenvironment of DNPC. These data have provided the rationale for a clinical trial targeting DKK1 in mCRPC (ClinicalTrials.gov identifier: NCT03837353 )