Growth differentiation factor 11 (GDF11) - a promising anti-ageing factor - is highly concentrated in platelets.

Recent research suggests that growth differentiation factor 11 (GDF11) could reverse age-related diseases and that its blood concentration decreases with age. This poses plasma from young donors as a therapeutic GDF11 source to treat age-related diseases. In addition, the tissue source of circulating GDF11 remains unknown. We analysed GDF11 levels in paired samples of serum, plasma and platelet lysate (PL) from 23 volunteers. Plasma and PL were collected by plateletpheresis. Here, we show that GDF11 is highly concentrated in platelets and that the circulating levels reported in previous studies could be biased as a result of serum sample manipulation.

Central nervous system prophylaxis with intrathecal liposomal cytarabine in a subset of high-risk patients with diffuse large B-cell lymphoma receiving first line systemic therapy in a prospective trial.

The dissemination in the central nervous system (CNS) is an uncommon but fatal complication occurring in patients with diffuse large B-cell lymphoma (DLBCL). Standard prophylaxis has been demonstrated to reduce CNS relapse and improve survival rates. Intrathecal (IT) liposomal cytarabine allows maintaining elevated drug levels in the cerebrospinal fluid for an extended period of time. Data on the efficacy and safety of liposomal cytarabine as CNS prophylaxis in patients with DLBCL are still insufficient. The objective of the present study was to evaluate the effectiveness and safety of the prophylaxis with IT liposomal cytarabine in prevention of CNS relapse in high-risk patients with DLBCL who were included in a trial of first line systemic therapy with 6 cycles of dose-dense R-CHOP every 14 days. Twenty-four (18.6 %) out of 129 patients were identified to have risk factors for CNS involvement, defined as follows: >30 % bone marrow infiltration, testes infiltration, retroperitoneal mass ≥10 cm, Waldeyer ring, or bulky cervical nodes involvement. Liposomal cytarabine (50 mg) was administered by lumbar puncture the first day of the 1st, 2nd, and 6th cycle of R-CHOP14 scheme. Among 70 IT infusions, grade 3-4 adverse events reported were headache (one patient) and nausea/vomiting (one patient). With a median follow-up of 40.1 months, no CNS involvement by DLBCL was observed in any patient. In conclusion, IT liposomal cytarabine is safe, feasible, and effective for CNS prophylaxis, causing few associated risks and little discomfort to patients with DLBCL.

In vivo adhesion of malignant B cells to bone marrow microvasculature is regulated by α4ß1 cytoplasmic-binding proteins.

Multiple myeloma (MM) and chronic lymphocytic leukemia (CLL) cells must attach to the bone marrow (BM) microvasculature before lodging in the BM microenvironment. Using intravital microscopy (IVM) of the BM calvariae we demonstrate that the α4ß1 integrin is required for MM and CLL cell firm arrest onto the BM microvasculature, while endothelial P-selectin and E-selectin mediate cell rolling. Talin, kindlin-3 and ICAP-1 are ß1-integrin-binding partners that regulate ß1-mediated cell adhesion. We show that talin and kindlin-3 cooperatively stimulate high affinity and strength of α4ß1-dependent MM and CLL cell attachment, whereas ICAP-1 negatively regulates this adhesion. A functional connection between talin/kindlin-3 and Rac1 was found to be required for MM cell attachment mediated by α4ß1. Importantly, IVM analyses with talin- and kindlin-3-silenced MM cells indicate that these proteins are needed for cell arrest on the BM microvasculature. Instead, MM cell arrest is repressed by ICAP-1. Moreover, MM cells silenced for talin and kindlin-3, and cultured on α4ß1 ligands showed higher susceptibility to bortezomib-mediated cell apoptosis. Our results highlight the requirement of α4ß1 and selectins for the in vivo attachment of MM and CLL cells to the BM microvasculature, and indicate that talin, kindlin-3 and ICAP-1 differentially control physiological adhesion by regulating α4ß1 activity.

Severe infections after single umbilical cord blood transplantation in adults with or without the co-infusion of CD34+ cells from a third-party donor: results of a multicenter study from the Grupo Español de Trasplante Hematopoyético (GETH).

BACKGROUND: Umbilical cord blood transplantation (CBT) is an established alternative source of stem cells in the setting of unrelated transplantation. When compared with other sources, single-unit CBT (sCBT) is associated with a delayed hematologic recovery, which may lead to a higher infection-related mortality (IRM). Co-infusion with the sCBT of CD34+ peripheral blood stem cells from a third-party donor (TPD) (sCBT + TPDCD34+) has been shown to markedly accelerate leukocyte recovery, potentially reducing the IRM. However, to our knowledge, no comparative studies have focused on severe infections and IRM with these 2 sCBT strategies. METHODS: A total of 148 consecutive sCBT (2000-2010, median follow-up 4.5 years) were included in a multicenter retrospective study to analyze the incidence and risk factors of IRM and severe viral and invasive fungal infections (IFIs). Neutrophil engraftment occurred in 90% of sCBT (n = 77) and 94% sCBT + TPDCD34+ (n = 71) recipients at a median of 23 and 12 days post transplantation, respectively (P < 0.01). RESULTS: The 4-year IRM was 24% and 20%, respectively (P = 0.7), with no differences at day +30 (5% and 4%, respectively) and day +100 (10% and 8%, respectively). In multivariate analysis early status of the underlying malignancy, cytomegalovirus (CMV)-seronegative recipient and high CD34+ cell content in the cord blood unit before cryostorage (≥1.4 × 10(5) /kg) were protective of IRM. Among the causes of IRM, bacterial infections and IFIs were more common in sCBT (15% vs. 4%), while CMV disease and parasitic infections were more common in the sCBT + TPDCD34+ cohort (5% vs. 16%). CONCLUSION: These data show that sCBT supported with TPDCD34(+) cells results in much shorter periods of post-transplant leukopenia, but the short- and long-term rates of IRM were comparable to those of sCBT, presumably because immune recovery is equally delayed in both graft types.

Immune reconstitution after cord blood transplants supported by coinfusion of mobilized hematopoietic stem cells from a third party donor.

Low severity of GVHD, substantial graft vs tumor (GVT) and slow development of protective immunity are well-documented features of cord blood transplants (CBT). We have evaluated the immune reconstitution of adult recipients of single-unit CBT supported by the coinfusion of third party donor (TPD) mobilized hematopoietic stem cells (MHSC), a procedure-'dual CB/TPD-MHSC transplant'-that results in early recovery of circulating granulocytes, high rates of CB engraftment and full chimerism. Cumulative recovery of natural killer and B cells at or above the median values of normal controls were 1.0 and 0.76 by the sixth and ninth months. Recovery of T cells was much slower, naive cells lagging behind those of memory and effector (committed) immunophenotypes. Serial analyses of signal joint TCR excision circles showed a general pattern of very low levels by the third month after CBT, followed by recovery to levels persistently similar or higher than those observed before transplantation and in normal controls. Our results are consistent with the clinical observations of substantial GVT effect together with low incidence of serious GVHD and slow development of protective immunity and suggest that thymic function contributes substantially to the recovery of T-cell populations in adults receiving dual CB/TPD-MHSC transplants.

Cord blood transplants supported by co-infusion of mobilized hematopoietic stem cells from a third-party donor.

This open label clinical study provides updated evaluation of the strategy of single unit cord blood transplants (CBTs) with co-infusion of third-party donor (TPD) mobilized hematopoietic stem cells (MHSC). Fifty-five adults with high-risk hematological malignancies, median age 34 years (16-60 years) and weight 70 kg (43-95 kg), received CBTs (median 2.39 x 10(7) total nucleated cell (TNC) per kg and 0.11 x 10(6) CD34+ per kg) and TPD-MHSC (median 2.4 x 10(6) CD34+ per kg and 3.2 x 10(3) CD3+ per kg). Median time to ANC and to CB-ANC >0.5 x 10(9)/l as well as to full CB-chimerism was 10, 21 and 44 days, with maximum cumulative incidences (MCI) of 0.96, 0.95 and 0.91. Median time to unsupported platelets >20 x 10(9)/l was 32 days (MCI 0.78). MCI for grades I-IV and III-IV acute GVHD (aGVHD) were 0.62 and 0.11; 12 of 41 patients (29%) who are at risk developed chronic GVHD, becoming severely extensive in three patients. Relapses occurred in seven patients (MCI=0.17). The main causes of morbi-mortality were post-engraftment infections. CMV reactivations were the most frequent, their incidence declining after the fourth month. Five-year overall survival and disease-free survival (Kaplan-Meier) were 56 % and 47% (63% and 54% for patients

[The clinical and radiological characteristics and evolution of incidentally diagnosed pulmonary thromboembolism]. / Diagnóstico casual de tromboembolismo pulmonar: descripción de las características clínicas y radiológicas y su evolución.

OBJECTIVES: To evaluate the cases of pulmonary embolism (PE) detected incidentally in our hospital, the associated risk factors, clinical and radiological characteristics, and evolution. MATERIAL AND METHODS: We retrospectively reviewed the reports of routine contrast-enhanced chest CT examinations performed during a 19-month period to detect cases in which PE was diagnosed incidentally. We found 18 cases of incidentally diagnosed PE and we reviewed the clinical histories and CT images of these patients to analyze the risk factors, clinical presentation, radiological characteristics, treatment, and evolution of PE in these cases. RESULTS: We found 18 patients (9 men and 9 women; mean age: 61 years) with incidentally detected PE. The main risk factor for developing PE was the presence of a neoplasm (n = 16). No PE-related symptoms were present in 12 patients. A multidetector CT scanner was used for the examination in most cases (n = 16). PE was centrally located in 16 patients. Five patients were not treated with anticoagulation and no embolic events occurred in these patients. Two of the remaining patients died because of PE. CONCLUSIONS: The incidental finding of PE can be common in oncological patients. Multidetector CT probably has a greater capacity for the incidental detection of PE in these patients. The outcome of incidentally detected PE can vary from death to remaining stable to spontaneous resolution.

Molecular heterogeneity in chronic lymphocytic leukemia is dependent on BCR signaling: clinical correlation.

Chronic lymphocytic leukemia (CLL), the most frequent form of adult leukemia in Western countries, is characterized by a highly variable clinical course. Expression profiling of a series of 160 CLL patients allowed interrogating the genes presumably playing a role in pathogenesis, relating the expression of functionally relevant signatures with the time to treatment. First, we identified genes relevant to the biology and prognosis of CLL to build a CLL disease-specific oligonucleotide microarray. Second, we hybridized a training series on the CLL-specific chip, generating a biology-based predictive model. Finally, this model was validated in a new CLL series. Clinical variability in CLL is related with the expression of two gene clusters, associated with B-cell receptor (BCR) signaling and mitogen-activated protein kinase (MAPK) activation, including nuclear factor-kappaB1 (NF-kappaB1). The expression of these clusters identifies three risk-score groups with treatment-free survival probabilities at 5 years of 83, 50 and 17%. This molecular predictor can be applied to early clinical stages of CLL. This signature is related to immunoglobulin variable region somatic hypermutation and surrogate markers. There is a molecular heterogeneity in CLL, dependent on the expression of genes defining BCR and MAPK/NF-kappaB clusters, which can be used to predict time to treatment in early clinical stages.

AT514, a cyclic depsipeptide from Serratia marcescens, induces apoptosis of B-chronic lymphocytic leukemia cells: interference with the Akt/NF-kappaB survival pathway.

Clinical treatment of B-cell chronic lymphocytic leukemia (B-CLL) is limited by the progressive drug resistance and nonselectivity of most drugs towards malignant cells. Depsipeptides are present in certain bacteria and display potent antitumor activity. We have studied the effect of the novel cyclodepsipeptide AT514 (serratamolide) from Serratia marcescens on B-CLL cell viability. AT514 induced apoptosis of B-CLL cells from the 21 patients studied, as confirmed by Annexin-V binding and nuclei condensation, with an average IC50 of 13 microM. AT514 was effective in those B-CLL cases resistant to fludarabine, but had no effect on normal PBL. AT514 preferentially activated the intrinsic apoptotic pathway, as evidenced by loss of mitochondrial membrane potential, release of cytochrome c and activation of caspase-9 and -3, but not of caspase-8. Importantly, AT514 interfered with phosphatidylinositol-3 kinase and protein kinase C survival signals since it increased the apoptotic effect of LY294002 and Bisl inhibitors, and induced Akt dephosphorylation at Ser 473. AT514 also decreased NF-kappaB activity by dramatically reducing the levels of p65 in B-CLL. This was confirmed on functional assays using NF-kappaB-luc-transfected Raji cells and transgenic mice. Our results establish that AT514 induces apoptosis of primary B-CLL cells and could be useful for clinical treatment of this malignancy.

A sustained activation of PI3K/NF-kappaB pathway is critical for the survival of chronic lymphocytic leukemia B cells.

The progressive rise of mature CD5+ B lymphocytes, despite the low proportion of proliferating cells, has led to the notion that B cell chronic lymphocytic leukemia (B-CLL) is primarily related to defective apoptosis. The microenvironment likely plays a prominent role because the malignant cells progressively accumulate in vivo, whereas they rapidly undergo spontaneous apoptosis when cultured in vitro. To assess microenvironment-mediated survival signals, B-CLL cells were cultured with a murine fibroblast cell line, Ltk-, with and without an agonistic antibody to CD40. Spontaneous apoptosis was associated with the loss of Akt and NF-kappaB activities. Interactions with fibroblasts sustained a basal level of Akt and NF-kappaB activities, which was dependent on phosphatidylinositol-3 kinase (PI3K). Constitutive activity of the PI3K pathway in B-CLL cells when cultured with fibroblasts prevented the downregulation of the prosurvival Bcl-2 family protein Bcl-xL and the caspase inhibitor proteins FLIPL and XIAP, and consequently caspase-3 activation and apoptosis. CD40 crosslinking in B-CLL cells did not further prevent murine fibroblasts-mediated apoptosis but induced cell proliferation, which was associated with an increase of Akt and NF-kappaB activation compared with cells cultured with fibroblasts alone. The PI3K pathway seems to play a pivotal role in B-CLL cell survival and growth.

The class II tumor-suppressor gene RARRES3 is expressed in B cell lymphocytic leukemias and down-regulated with disease progression.

The molecular pathogenesis of B cell chronic lymphocytic leukemia (B-CLL), the most common form of leukemia, remains unknown. We have used the mRNA differential display technique to analyze genes that may be involved in the development/progression of B-CLL. We have identified the tumor suppressor retinoic acid receptor responder 3 (RARRES3) as a B-CLL-related gene. RARRES3 maps to chromosome band 11q23, a region frequently deleted in lymphoproliferative disorders. To assess the potential involvement of RARRES3 in leukemogenesis, we examined 24 cases of B-CLL, 10 of acute lymphocytic leukemia (ALL) and five related cell lines by RT-PCR and sequence analyses. We report a correlation between RARRES3 down-regulation and B-CLL progression. We also found decreased RARRES3 gene levels in ALL cases and in the five cell lines studied. We did not find mutations in any of the leukemia samples assayed, including those with 11q23 deletion. These results indicate that RARRES3 may play a role in B-CLL progression.

Cord blood transplants: early recovery of neutrophils from co-transplanted sibling haploidentical progenitor cells and lack of engraftment of cultured cord blood cells, as ascertained by analysis of DNA polymorphisms.

The number of infused cells is a very important factor in cord blood transplant (CBT) engraftment. Prior ex vivo expansion of aliquots of transplanted cord blood (CB) units is being investigated as a procedure to increase engraftment potential, but results are difficult to evaluate due to a lack of markers for assessing the contribution of expanded cells. We transplanted five patients, infusing the best available CB unit and cells from a second donor simultaneously. In two patients, these cells were obtained from another frozen CB unit by CD34(+)positive selection and culture expansion; the other three patients received uncultured highly purified haploidentical CD34(+) cells. The first two patients had DNA from the culture expanded CB cells detected only for a few days around day +11 when the absolute neutrophil count (ANC) was >200/microl; thereafter and when the ANC was <500/microl, only donor DNA from the uncultured CB was detected. For the other three patients, DNA analysis showed early and transient granulocyte engraftment of haploidentical cells, progressively replaced by the CB-derived granulocytes. We concluded that: (1) simultaneous infusion of lymphocyte-depleted HLA highly mismatched haematopoietic progenitor cells has not produced unfavourable effects for CBT; (2) the double transplant model is suitable for evaluating the engraftment potential of ex vivocultured CB cells in the clinical setting; (3) the culture conditions used did not result in early recovery of ANC; and (4) co-transplantation of purified uncultured HLA haploidentical CD34(+) cells may reduce the time of neutropenia following CBT.

Variability in the levels of PML-RAR alpha fusion transcripts detected by the laboratories participating in an external quality control program using several reverse transcription polymerase chain reaction protocols.

BACKGROUND AND OBJECTIVES: The detection of PML-RAR by reverse transcription (RT) polymerase chain reaction (PCR) in acute promyelocytic leukemia (APL) patients who are in hematologic remission influences therapeutic decision making in several trials. In the light of this, the Spanish group has recently designed an external quality assessment program (EQAP) of RT-PCR detection of PML-RAR, which includes a study of sensitivity of the participating laboratories. DESIGN AND METHODS: Eighteen laboratories were involved in the program. Ten laboratories followed the method of Biondi et al., 5 employed that of Borrow et al. and the 3 remaining used other protocols. The sensitivity was studied in five rounds of quality control. The first two shipments consisted of dilutions of NB4 RNA into non-APL RNA. The third round consisted of serial dilutions of the NB4 cell line into HL60 cells. The fourth and five rounds consisted of plasmid dilutions containing the bcr1 and bcr3 PML-RAR isoforms. RESULTS: The results showed that the distinct methods allow detection of the PML-RAR hybrid up to a dilution of 10(-4), and exceptionally, up to 10(-5). The laboratories following the method of Biondi et al. usually detected the 10(-3) dilution and less frequently the 10(-4) one, whereas those using other methods usually detected PML-RAR transcript in the 10(-4) dilution, and less commonly in the 10(-5) dilution. However, each of the PCR methods used by EQAP participating laboratories successfully detected at least 50 copies of PML-RAR alpha fusion transcript in plasmid dilution controls. INTERPRETATION AND CONCLUSIONS: The results point to heterogeneous sensitivity amongst participating laboratories. This may reflect differences in methodology, although variations in sample quality may also account for discrepant findings.

Association and clonal distribution of trisomy 12 and 13q14 deletions in chronic lymphocytic leukaemia.

The coexistence of trisomy 12 and deletions of chromosome 13 (13q12-q32) has rarely been observed in chronic lymphocytic leukaemia (CLL). Fluorescence in situ hybridization (FISH) performed on 600 consecutive CLL patients revealed the association of trisomy 12 and 13q14 deletion, of at least one of the three markers analysed (RB1, D13S319 and D13S25), in 55 cases (9% of 600 and 46% of 120 trisomy 12 cases). Trisomy 12 and isolated RB1 deletion were seen in 14/120 cases, trisomy 12 and D13S319/D13S25 deletion with diploid RB1 in 19/118, and trisomy 12 and deletion encompassing the three 13q markers studied in 22/118 cases. The heterogenous distribution of trisomy 12 and 13q deletions within the neoplastic B cells suggests that they are secondary rather than primary events in CLL leukaemogenesis.

Molecular cytogenetic analysis in splenic lymphoma with villous lymphocytes: frequent allelic imbalance of the RB1 gene but not the D13S25 locus on chromosome 13q14.

Structural abnormalities of chromosome 13q are one of the most frequent genetic aberrations in human tumors. 13q rearrangements are, however, infrequent in splenic lymphoma with villous lymphocytes (SLVL) by karyotype analysis. We have investigated the incidence of 13q14 deletions in a series of 74 SLVL cases by interphase fluorescence in situ hybridization using unique sequence probes for the RB1 and the D13S25 loci, which are frequently deleted in chronic lymphocytic leukemia. Chromosome 12 was also evaluated by fluorescence in situ hybridization using a pericentromeric DNA probe. 13q14 deletion was detected in 37 of 74 (50%) tumors. Thirty-five cases (47%) exhibited monoallelic loss of RB1, and 9 (12%) showed hemizygous D13S25 deletion. Seven cases displayed coexistence of RB1 and D13S25 deletion. Trisomy 12 was detected in 2 of 74 (3%) tumors. G-banding analysis in 40 tumors showed no interstitial deletion of 13q14 in any case. In contrast with the molecular findings observed in chronic lymphocytic leukemia, our results indicate that trisomy 12 is an uncommon chromosomal aberration in SLVLs, and microdeletion of 13q14 at the RB1 locus but not D13S25 is a frequent and specific genetic event in this disease, suggesting that allelic loss of the RB1 gene may play a role in the pathogenesis of SLVL.