246 research outputs found
Cytotoxic activity of the novel Akt inhibitor, MK-2206, in T-cell acute lymphoblastic leukemia.
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive neoplastic disorder arising from T-cell progenitors. T-ALL accounts for
15% of newly diagnosed ALL cases in children and 25% in adults. Although the prognosis of T-ALL has improved, due to the use of
polychemotherapy schemes, the outcome of relapsed/chemoresistant T-ALL cases is still poor. A signaling pathway that is
frequently upregulated in T-ALL, is the phosphatidylinositol 3-kinase/Akt/mTOR network. To explore whether Akt could represent a
target for therapeutic intervention in T-ALL, we evaluated the effects of the novel allosteric Akt inhibitor, MK-2206, on a panel of
human T-ALL cell lines and primary cells from T-ALL patients. MK-2206 decreased T-ALL cell line viability by blocking leukemic cells
in the G0/G1 phase of the cell cycle and inducing apoptosis. MK-2206 also induced autophagy, as demonstrated by an increase in
the 14-kDa form of LC3A/B. Western blotting analysis documented a concentration-dependent dephosphorylation of Akt and its
downstream targets, GSK-3a/b and FOXO3A, in response to MK-2206. MK-2206 was cytotoxic to primary T-ALL cells and induced
apoptosis in a T-ALL patient cell subset (CD34þ/CD4/CD7), which is enriched in leukemia-initiating cells. Taken together, our
findings indicate that Akt inhibition may represent a potential therapeutic strategy in T-ALL
Visceral Leishmaniasis: Epidemiology, Diagnosis, and Treatment Regimens in Different Geographical Areas with a Focus on Pediatrics
Visceral Leishmaniasis (VL) is a vector-borne disease caused by an intracellular protozoa of the genus Leishmania that can be lethal if not treated. VL is caused by Leishmania donovani in Asia and in Eastern Africa, where the pathogens’ reservoir is represented by humans, and by Leishmania infantum in Latin America and in the Mediterranean area, where VL is a zoonotic disease and dog is the main reservoir. A part of the infected individuals become symptomatic, with irregular fever, splenomegaly, anemia or pancytopenia, and weakness, whereas others are asymptomatic. VL treatment has made progress in the last decades with the use of new drugs such as liposomal amphotericin B, and with new therapeutic regimens including monotherapy or a combination of drugs, aiming at shorter treatment duration and avoiding the development of resistance. However, the same treatment protocol may not be effective all over the world, due to differences in the infecting Leishmania species, so depending on the geographical area. This narrative review presents a comprehensive description of the clinical picture of VL, especially in children, the diagnostic approach, and some insight into the most used pharmacological therapies available worldwide
AMP-dependent kinase/mammalian target of rapamycin complex 1 signaling in T-cell acute lymphoblastic leukemia: therapeutic implications.
The mammalian target of rapamycin (mTOR) serine/threonine
kinase is the catalytic subunit of two multi-protein complexes,
referred to as mTORC1 and mTORC2. Signaling downstream
of mTORC1 has a critical role in leukemic cell biology by
controlling mRNA translation of genes involved in both cell
survival and proliferation. mTORC1 activity can be downmodulated
by upregulating the liver kinase B1/AMP-activated
protein kinase (LKB1/AMPK) pathway. Here, we have explored
the therapeutic potential of the anti-diabetic drug, metformin
(an LKB1/AMPK activator), against both T-cell acute lymphoblastic
leukemia (T-ALL) cell lines and primary samples
from T-ALL patients displaying mTORC1 activation. Metformin
affected T-ALL cell viability by inducing autophagy and
apoptosis. However, it was much less toxic against proliferating
CD4þ T-lymphocytes from healthy donors. Western blot
analysis demonstrated dephosphorylation of mTORC1 downstream
targets. Unlike rapamycin, we found a marked inhibition
of mRNA translation in T-ALL cells treated with metformin.
Remarkably, metformin targeted the side population of T-ALL
cell lines as well as a putative leukemia-initiating cell subpopulation
(CD34þ/CD7/CD4) in patient samples. In conclusion,
metformin displayed a remarkable anti-leukemic activity,
which emphasizes future development of LKB1/AMPK activators
as clinical candidates for therapy in T-ALL.
Leukemia (2012) 26, 91–100; doi:10.1038/leu.2011.269;
published online 4 October 201
Synergistic cytotoxic effects of bortezomib and CK2 inhibitor CX-4945 in acute lymphoblastic leukemia: turning offthe prosurvival ER chaperone BIP/Grp78 and turning on the proapoptotic NF-κB
The proteasome inhibitor bortezomib is a new targeted treatment option for refractory or relapsed acute lymphoblastic leukemia (ALL) patients. However, a limited efficacy of bortezomib alone has been reported. A terminal pro-apoptotic endoplasmic reticulum (ER) stress/unfolded protein response (UPR) is one of the several mechanisms of bortezomib-induced apoptosis. Recently, it has been documented that UPR disruption could be considered a selective anti-leukemia therapy. CX- 4945, a potent casein kinase (CK) 2 inhibitor, has been found to induce apoptotic cell death in T-ALL preclinical models, via perturbation of ER/UPR pathway. In this study, we analyzed in T- and B-ALL preclinical settings, the molecular mechanisms of synergistic apoptotic effects observed after bortezomib/CX-4945 combined treatment. We demonstrated that, adding CX-4945 after bortezomib treatment, prevented leukemic cells from engaging a functional UPR in order to buffer the bortezomibmediated proteotoxic stress in ER lumen. We documented that the combined treatment decreased pro-survival ER chaperon BIP/Grp78 expression, via reduction of chaperoning activity of Hsp90. Bortezomib/CX-4945 treatment inhibited NF-κB signaling in T-ALL cell lines and primary cells from T-ALL patients, but, intriguingly, in B-ALL cells the drug combination activated NF-κB p65 pro-apoptotic functions. In fact in B-cells, the combined treatment induced p65-HDAC1 association with consequent repression of the anti-apoptotic target genes, Bcl-xL and XIAP. Exposure to NEMO (IKKγ)-binding domain inhibitor peptide reduced the cytotoxic effects of bortezomib/CX-4945 treatment. Overall, our findings demonstrated that CK2 inhibition could be useful in combination with bortezomib as a novel therapeutic strategy in both T- and B-ALL
Weight cycling in treatment-seeking obese persons: data from the QUOVADIS study
OBJECTIVE: To determine parameters of weight history useful for the assessment of weight cycling and their association with
psychological distress and binge eating.
DESIGN: Cross-sectional.
SUBJECTS: A total of 1889 treatment-seeking obese subjects, enrolled by 25 Italian centers (78% female subject), aged 20–65 y
(median 45); 1691 reported previous efforts to lose weight (median age of first dieting, 30 y).
MEASUREMENTS: The number of yearly attempts to lose weight, weight gain since age 20 y, cumulative weight loss and
gain were checked by a predefined structured interview. Psychological distress was tested by means of Symptom Check-List 90
(SCL-90), Binge Eating Scale (BES) and Three Factor Eating Questionnaire (TFEQ).
RESULTS: Differences in anthropometric, clinical and psychological parameters were observed in relation to previous attempts
to lose weight. Patients in the upper quartile of parameters of weight history were considered weight cyclers. In multivariate
logistic regression analysis, after correction for age, sex and BMI, a high BES score was the only factor systematically associated
with a high frequency of dieting (OR, 1.70; 95% confidence interval, 1.22–2.36; P¼0.022), with higher cumulative weight loss
(1.42; 1.12–1.80; P¼0.003) and cumulative weight gain (1.38; 1.06–1.79; P¼0.017). However, the sensitivity, specificity and
positive predictive value of a high BES score were very low to detect cyclers. Weight cycling did not carry a higher risk of
complicating diseases.
CONCLUSIONS: Weight cycling is associated with psychological distress, and binge eating independently increases the risk, but
cannot be used to predict cycling. Also, obese patients who do not experience overeating as a loss of control discontinue
treatment or regain weight following therapy
Assessment of the Precision ID Identity Panel kit on challenging forensic samples
The performance of the Precision ID Identity Panel (Thermo Fisher Scientific) was assessed on a set of 87 forensic samples with different levels of degradation for which a reference sample from the \u201csame donor\u201d or from a \u201cfirst degree relative\u201d was available. PCR-MPS analysis was performed with DNA input ranging from 1 ng to 12 pg and through 21-26 PCR cycles, in replicate tests, and a total number of 255 libraries were sequenced on the Ion Personal Genome Machine\u2122 (PGM\u2122) System. The evaluation of the molecular data allowed to set a fix threshold for locus call at 50 x which suitably worked even when low amounts of degraded DNA (12 pg) were investigated. In these analytical conditions, in fact, 25 PCR cycles allowed the genotyping of about 50% and 35% of the autosomal and the Y-specific markers on average, respectively, for each single amplification with a negligible frequency of drop ins (0.01 %). On the other hand, drop out artefacts reached 18-23% when low copy number and degraded DNA samples were studied, with surviving alleles showing more than 600 reads in 2.9 % of the cases. Our data pointed out that the Precision ID Identity Panel allowed accurate typing of almost any amount of good quality/moderately degraded DNA samples, in duplicate tests.
The analysis of low copy number DNAs evidenced that the same allele of a heterozygous genotype could be lost twice, thus suggesting that a third amplification could be useful for a correct genotype assignment in these peculiar cases. Using the consensus approach, a limited number of genotyping errors were computed and about 37% of the autosomal markers was finally typed with a corresponding combined random match probability of at least 1.6 x 10-13, which can be considered an excellent result for this kind of challenging samples. In the end, the results presented in this study emphasize the crucial role of the expert opinion in the correct evaluation of artefacts arising from PCR-MPS technology that could potentially lead to genetic mistyping
Rapid communications Ongoing outbreak of visceral leishmaniasis in Bologna
(VL) cases has recently been reported in Bologna Province in northern Italy. Over six months from November 2012 to May 2013, 14 cases occurred, whereas the average number of cases per year was 2.6 (range: 0–8) in 2008 to 2012. VL was diagnosed in a median of 40 days (range: 15–120) from disease onset. This delay in diagnosis shows the need for heightened awareness of clinicians for autochthonous VL in Europe. From November 2012 to May 2013, public health authorities, microbiologists and clinicians in Bologna Province, northern Italy, noted an upsurge in human cases of visceral leishmaniasis. During these six months, 14 cases were notified, an over five-fold increase compared with the annual average of 2.
Toxicity and Clinical Results after Proton Therapy for Pediatric Medulloblastoma: A Multi-Centric Retrospective Study
Medulloblastoma is the most common malignant brain tumor in children. Even if current treatment dramatically improves the prognosis, survivors often develop long-term treatment-related sequelae. The current radiotherapy standard for medulloblastoma is craniospinal irradiation with a boost to the primary tumor site and to any metastatic sites. Proton therapy (PT) has similar efficacy compared to traditional photon-based radiotherapy but might achieve lower toxicity rates. We report on our multi-centric experience with 43 children with medulloblastoma (median age at diagnosis 8.7 years, IQR 6.6, M/F 23/20; 26 high-risk, 14 standard-risk, 3 ex-infant), who received active scanning PT between 2015 and 2021, with a focus on PT-related acute-subacute toxicity, as well as some preliminary data on late toxicity. Most acute toxicities were mild and manageable with supportive therapy. Hematological toxicity was limited, even among HR patients who underwent hematopoietic stem-cell transplantation before PT. Preliminary data on late sequelae were also encouraging, although a longer follow-up is needed
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