Angular distribution of neutron production by proton and carbon-ion therapeutic beams.

Carbon-ion beams are increasingly used in the clinical practice for external radiotherapy treatments of deep-seated tumors. At therapeutic energies, carbon ions yield significant secondary products, including neutrons, which may be of concern for the radiation protection of the patient and personnel. We simulated the neutron yield produced by proton and carbon-ion pencil beams impinging on a clinical phantom at three different angles: 15°, 45° and 90°, with respect to the beam axis. We validated the simulated results using the measured response of organic scintillation detectors. We compared the results obtained with FLUKA 2011.2 and MCNPX 2.7.0 based on three different physics models: Bertini, Isabel, and CEM. Over the different ions, energies, and angles, the FLUKA simulation results agree better with the measured data, compared to the MCNPX results. Simulations of carbon ions at low angles exhibit both the highest deviation from measured data and inter-model discrepancy, which is probably due to the different treatment of the pre-equilibrium stage. The reported neutron yield results could help in the comparison of carbon-ion and proton treatments in terms of secondary neutron production for radiation protection applications.

Contribution of the interferon-gamma release assay to tuberculosis diagnosis in children and adolescents.

SETTING: As conclusive data on the performance of interferon-gamma release assays (IGRAs) in paediatric TB are lacking, many guidelines do not recommend their use for TB diagnosis in this population in Brazil. OBJECTIVE: To evaluate the performance of an IGRA by investigating its concordance with the tuberculin skin test (TST) and the role of IGRAs in clinical management and treatment outcomes in children with TB. DESIGN: A historic cohort study was used to evaluate the performance of T-SPOT®.TB (ELISpot) and other tests, such as the TST, in paediatric patients with or without immunodeficiency who were under investigation for latent tuberculous infection (LTBI) or active tuberculosis (TB). RESULTS: Of 86 paediatric patients evaluated, 41 (48%) were immunocompetent and 45 (52%) immunocompromised. All patients underwent T-SPOT.TB, while 63 underwent both ELISpot and TST; test results were concordant in 50 patients (79.4%): 22/31 (71%) in immunocompetent (κ = 0.418, P = 0.02) and 28/32 (87.5%) in immunocompromised patients (κ = 0.526, P = 0.003). TB was diagnosed on the basis of the ELISpot result in 21% (18/86) cases; the contribution of the ELISpot assay was greater in immunocompetent patients than in those who were immunocompromised (13/41, 31.7% vs. 5/45, 11.1%, χ2 P = 0.038). CONCLUSION: ELISpot and TST results were moderately concordant in both groups of patients. ELISpot contribution was higher among immunocompetent patients than among immunocompromised patients.

Effects of miRNA-15 and miRNA-16 expression replacement in chronic lymphocytic leukemia: implication for therapy.

Chronic lymphocytic leukemia (CLL) clones are characterized by loss of a critical region in 13q14.3, (del(13)(q14)) involving the microRNA (miRNA) cluster miR-15a and miR-16-1. We have investigated the effects of replacement of miR-15a and miR-16-1. CLL cells transfected with these miRNA mimics exhibited a decrease in cell viability in vitro and impaired capacity for engraftment and growth in NOD/Shi-scid,γcnull (NSG) mice. No synergistic effects were observed when the two miRNA mimics were combined. The phenomena were not restricted to CLL with the del(13)(q14) lesion. Similar effects induced by miRNA mimics were seen in cells with additional chromosomal abnormalities with the exception of certain CLL clones harboring TP53 alterations. Administration of miRNA mimics to NSG mice previously engrafted with CLL clones resulted in substantial tumor regression. CLL cell transfection with miR-15a and miR-16-1-specific inhibitors resulted in increased cell viability in vitro and in an enhanced capacity of the engrafted cells to grow in NSG mice generating larger splenic nodules. These data demonstrate that the strong control by miR-15a and miR-16-1 on CLL clonal expansion is exerted also at the level of full-blown leukemia and provide indications for a miRNA-based therapeutic strategy.

lncRNA profiling in early-stage chronic lymphocytic leukemia identifies transcriptional fingerprints with relevance in clinical outcome.

Long non-coding RNAs (lncRNAs) represent a novel class of functional RNA molecules with an important emerging role in cancer. To elucidate their potential pathogenetic role in chronic lymphocytic leukemia (CLL), a biologically and clinically heterogeneous neoplasia, we investigated lncRNAs expression in a prospective series of 217 early-stage Binet A CLL patients and 26 different subpopulations of normal B-cells, through a custom annotation pipeline of microarray data. Our study identified a 24-lncRNA-signature specifically deregulated in CLL compared with the normal B-cell counterpart. Importantly, this classifier was validated on an independent data set of CLL samples. Belonging to the lncRNA signature characterizing distinct molecular CLL subgroups, we identified lncRNAs recurrently associated with adverse prognostic markers, such as unmutated IGHV status, CD38 expression, 11q and 17p deletions, and NOTCH1 mutations. In addition, correlation analyses predicted a putative lncRNAs interplay with genes and miRNAs expression. Finally, we generated a 2-lncRNA independent risk model, based on lnc-IRF2-3 and lnc-KIAA1755-4 expression, able to distinguish three different prognostic groups in our series of early-stage patients. Overall, our study provides an important resource for future studies on the functions of lncRNAs in CLL, and contributes to the discovery of novel molecular markers with clinical relevance associated with the disease.

Rate of tuberculosis infection in children and adolescents with household contact with adults with active pulmonary tuberculosis as assessed by tuberculin skin test and interferon-gamma release assays.

Tuberculosis (TB) infection was evaluated in Brazilian immunocompetent children and adolescents exposed and unexposed (control group) to adults with active pulmonary TB. Both groups were analysed by clinical and radiological assessment, TST, QFT-IT and T-SPOT.TB. The three tests were repeated after 8 weeks in the TB-exposed group if results were initially negative. Individuals with latent tuberculosis infection (LTBI) were treated and tests were repeated after treatment. Fifty-nine TB-exposed and 42 controls were evaluated. Rate of infection was 69·5% and 9·5% for the exposed and control groups, respectively. The exposed group infection rate was 61% assessed by TST, 57·6% by T-SPOT.TB, and 59·3%, by QFT-IT. No active TB was diagnosed. Agreement between the three tests was 83·1% and 92·8% in the exposed and control groups, respectively. In the exposed group, T-SPOT.TB added four TB diagnoses [16%, 95% confidence interval (CI) 1·6-30·4] and QFT-IT added three TB diagnoses (12%, 95% CI 0-24·7) in 25 individuals with negative tuberculin skin test (TST). Risk factors associated to TB infection were contact with an adult with active TB [0-60 days: odds ratio (OR) 6·9; >60 days: OR 27·0] and sleeping in the same room as an adult with active TB (OR 5·2). In Brazilian immunocompetent children and adolescents, TST had a similar performance to interferon-gamma release assays and detected a high rate of LTBI.

In vivo radiobiological assessment of the new clinical carbon ion beams at CNAO.

In this article, the in vivo study performed to evaluate the uniformity of biological doses within an hypothetical target volume and calculate the values of relative biological effectiveness (RBE) at different depths in the spread-out Bragg peak (SOBP) of the new CNAO (National Centre for Oncological Hadrontherapy) carbon beams is presented, in the framework of a typical radiobiological beam calibration procedure. The RBE values (relative to (60)Co γ rays) of the CNAO active scanning carbon ion beams were determined using jejunal crypt regeneration in mice as biological system at the entrance, centre and distal end of a 6-cm SOBP. The RBE values calculated from the iso-effective doses to reduce crypt survival per circumference to 10, ranged from 1.52 at the middle of the SOBP to 1.75 at the distal position and are in agreement with those previously reported from other carbon ion facilities. In conclusion, this first set of in vivo experiments shows that the CNAO carbon beam is radiobiologically comparable with the NIRS (National Institute of Radiological Sciences, Chiba, Japan) and GSI (Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany) ones.

Cardiovascular manifestations of Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a rare inflammatory disorder of unknown etiology, characterised by diffuse organ infiltration of CD68-positive, CD1a-negative, S100-low/negative foamy histiocytes. It is a non-Langerhans cell histiocytosis which invariably involves bones (96% of cases). Extraskeletal involvement is observed in about 50% of cases. Cardiovascular involvement affects more than 20% of patients and associates with poor prognosis, conferring a reduced response to treatment. Frequent findings are pericardial effusion (24% of patients), "coated aorta", a perivascular circumferential thickening of the aorta, and pericardial thickening. Other typical features include right atrial mass with pseudo-tumoural appearance and histiocytes' infiltration of right atrial walls, atrioventricular sulcus and interatrial septum. After the recent introduction of cardiac cine MRI in the clinical assessment of patients affected by ECD, a growing body of case reports and retrospective data showed that cardiovascular involvement is present more frequently than previously thought and that it is relatively often asymptomatic. Hence, clinicians should systematically screen ECD patients for occult cardiovascular involvement by means of highly sensitive imaging tools. Despite these recent novelties, comprehensive literature reviews focusing on ECD cardiovascular involvement and its imaging assessment in the last decade are lacking.

A new version of the LUPIN detector: improvements and latest experimental verification.

LUPIN-II is an upgraded version of LUPIN, a novel rem counter first developed in 2010 specifically conceived to work in pulsed neutron fields (PNFs). The new version introduces some modifications that improve the performance of the detector, in particular extending its upper detection limit in PNFs. This paper discusses the characteristics and the performance of the instrument. Measurements have been carried out in radiation fields characterized by very different conditions: the detector has first been exposed in PNFs with intensity up to 5 µSv per burst, where it could keep the H*(10) underestimation below 20% up to 500 nSv per burst. It has then been tested in operational conditions around particle accelerators, where it has shown performances similar to that of ionization chambers. Its proper functioning has also been verified in high energy mixed fields, where the experimental results matched the Monte Carlo predictions. Its neutron/photon discrimination capability has been tested in a steady-state photon field where, via an innovative technique based on a threshold set on the derivative of the current signal, it was capable of rejecting a photon H*(10) rate of about 25 mSv/h, and in a mixed neutron/photon field, where a time-based discrimination method was employed.

Evaluation of a personal and environmental dosemeter based on CR-39 track detectors in quasi-monoenergetic neutron fields.

In this paper, the evaluation of the dosimetric capability of a detector based on a CR-39 solid-state nuclear track detector coupled to a 1 cm thickness of PMMA radiator was made with the aim of understanding the applicability of this technique to personal and environmental neutron dosimetry. The dosemeter has been exposed to monoenergetic and quasi-monoenergetic neutron beams at PTB in Braunschweig, Germany and at Ithemba Laboratories, in Faure, South Africa, with peak energies ranging from 0.565 to 100 MeV. The results showed a response that is almost independent of the neutron energy in the whole energy range.

A comparison of the response of PADC neutron dosemeters in high-energy neutron fields.

Within the framework of the EURADOS Working Group 11, a comparison of passive neutron dosemeters in high-energy neutron fields was organised in 2011. The aim of the exercise was to evaluate the response of poly-allyl-glycol-carbonate neutron dosemeters from various European dosimetry laboratories to high-energy neutron fields. Irradiations were performed at the iThemba LABS facility in South Africa with neutrons having energies up to 66 and 100 MeV.

A prognostic model based on combining estrogen receptor expression and Ki-67 value after neoadjuvant chemotherapy predicts clinical outcome in locally advanced breast cancer: extension and analysis of a previously reported cohort of patients.

BACKGROUND: Ki-67 expression has gained attention as a breast cancer prognostic factor, however its significance in the remaining malignant cells after neoadjuvant chemotherapy (NAC) has been rarely examined. This investigation, extension and analysis of a previously reported cohort of patients, evaluates the significance of Ki-67 and estrogen receptor (ER) expression after NAC in LABC (locally advanced breast cancer). PATIENTS AND METHODS: clinical stage, tumor size, clinical and pathological lymph node involvement, Ki-67, ER, progesterone receptor (PgR), HER2 expression, grading and clinical response were evaluated before and after NAC in 110 patients with LABC. Ki-67 expression was assessed both in pre and post-therapy histological samples, using >15% positive cells as cut-off value to distinguish high from low Ki-67 expressing tumors. RESULTS: six patients (5.45%) attained pCR after NAC. A significant relationship between elevated post-CT Ki-67 and ER expression was showed at Cox multivariate analysis of disease free survival (DFS). On univariate analysis high post-chemotherapy Ki-67 and ER status were associated with worse survival; at multivariate model included these results were confirmed. Based on these two parameters, a prognostic model identified two different groups: low risk (low postchemotherapy Ki-67 and ER positive, or either high post-chemotherapy Ki-67 or ER negative), and high risk (high post-chemotherapy Ki-67 and ER negative). The low risk group showed a good prognosis (median OS still not reached), while the high risk group had a worse OS (median 41 months). CONCLUSIONS: Ki-67 value after NAC and ER status could predict a worse prognosis among LABC patients treated with NAC.

miR-29b sensitizes multiple myeloma cells to bortezomib-induced apoptosis through the activation of a feedback loop with the transcription factor Sp1.

MicroRNAs (miRNAs) with tumor-suppressor potential might have therapeutic applications in multiple myeloma (MM) through the modulation of still undiscovered molecular pathways. Here, we investigated the effects of enforced expression of miR-29b on the apoptotic occurrence in MM and highlighted its role in the context of a new transcriptional loop that is finely tuned by the proteasome inhibitor bortezomib. In details, in vitro growth inhibition and apoptosis of MM cells was induced by either transient expression of synthetic miR-29b or its stable lentivirus-enforced expression. We identified Sp1, a transcription factor endowed with oncogenic activity, as a negative regulator of miR-29b expression in MM cells. Since Sp1 expression and functions are regulated via the 26S proteasome, we investigated the effects of bortezomib on miR-29b-Sp1 loop, showing that miR-29b levels were indeed upregulated by the drug. At the same time, the bortezomib/miR-29b combination produced significant pro-apoptotic effects. We also demonstrated that the PI3K/AKT pathway plays a major role in the regulation of miR-29b-Sp1 loop and induction of apoptosis in MM cells. Finally, MM xenografts constitutively expressing miR-29b showed significant reduction of their tumorigenic potential. Our findings indicate that miR-29b is involved in a regulatory loop amenable of pharmacologic intervention and modulates the anti-MM activity of bortezomib in MM cells.

The expression pattern of small nucleolar and small Cajal body-specific RNAs characterizes distinct molecular subtypes of multiple myeloma.

Small nucleolar RNAs (snoRNAs) and small Cajal body-specific RNAs (scaRNAs) are non-coding RNAs involved in the maturation of other RNA molecules and generally located in the introns of host genes. It is now emerging that altered sno/scaRNAs expression may have a pathological role in cancer. This study elucidates the patterns of sno/scaRNAs expression in multiple myeloma (MM) by profiling purified malignant plasma cells from 55 MMs, 8 secondary plasma cell leukemias (sPCLs) and 4 normal controls. Overall, a global sno/scaRNAs downregulation was found in MMs and, even more, in sPCLs compared with normal plasma cells. Whereas SCARNA22 resulted the only sno/scaRNA characterizing the translocation/cyclin D4 (TC4) MM, TC2 group displayed a distinct sno/scaRNA signature overexpressing members of SNORD115 and SNORD116 families located in a region finely regulated by an imprinting center at 15q11, which, however, resulted overall hypomethylated in MMs independently of the SNORD115 and SNORD116 expression levels. Finally, integrative analyses with available gene expression and genome-wide data revealed the occurrence of significant sno/scaRNAs/host genes co-expression and the putative influence of allelic imbalances on specific snoRNAs expression. Our data extend the current view of sno/scaRNAs deregulation in cancer and add novel information to the bio-molecular complexity of plasma cell dyscrasias.

Mutational and haplotype map of NOTCH3 in a cohort of Italian patients with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL).

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), the most common form of familial vascular dementia, is caused by mutations of the NOTCH3 gene. Approximately two hundred pathogenic mutations have been reported within five exons (exons 3, 4, 6, 11 and 19) which accounted for 78% of known mutations in worldwide series. We reported twenty-one NOTCH3 pathogenic mutations (including five novel ones) identified in 53 index Italian patients. Exons 4 (28%), 7 (21%) and 19 (24%) were the most frequently involved. To dissect genetic heterogeneity, we analyzed five haplotyped tagging single nucleotide polymorphisms (rs1044009, rs4809030, rs10426042, rs10423702 and rs3815188) in 95 patients, 39 unaffected pedigree members and 50 healthy controls. SNPs were analyzed using the Illumina VeraCode Universal Capture Beads technology by Allele Specific Primer Extension (ASPE). We identified ten different haplotypes named H1-H10; H1 was the most common haplotype in patients and controls and it was associated with at least twelve out of the twenty-one mutations. Detected mutations were not associated to specific haplotypes while genotyping was compatible with a possible founder effect for the novel p.S396C mutation which clustered in a restricted geographical area of northeast Italy. The results added on to the genetic heterogeneity of CADASIL and emphasized difficulties in designing algorithms for molecular diagnosis.

Prognostic factors in CLL.

Chronic lymphocytic leukemia (CLL) is a clinically heterogeneous disease, as some patients progress rapidly toward the more advanced studies, whereas others survive for a long period without the need for treatment. This heterogeneity of clinical course was somehow unexplained until studies on the CLL cell features disclosed that the CLL clones were heterogeneous and were characterized by different phenotypic and genotypic features in the different patients. On the basis of these observations, it was determined in retrospective studies that clones characterized by unmutated IGHV genes, and/or CD38 and/or ZAP-70 expression conferred a more severe prognosis to the CLL patients. Here, we present data on prospective studies carried out on Binet A-stage patients, in whom the markers were determined at diagnosis and their predictive value was assessed in comparison with chromosomal abnormalities and gene expression or micro RNA profiles. In addition, hypothesis on the potential pathogenetic role of these markers will be presented.

Proteasome inhibitors and modulators of angiogenesis in multiple myeloma.

Survival of patients affected by Multiple Myeloma (MM), a B-cell tumor of malignant plasma cells, has dramatically improved, owing to the recent introduction of the proteasome inhibitor (PI) Bortezomib and of the immunomodulatory drugs (IMiDs). This major advance originates from accumulating knowledge on MM biology, leading to the development of drugs targeting not only MM cells, but also their microenvironment. Indeed, the disease develops as a result of genetic abnormalities and of reciprocal interactions between MM cells and the permissive BM microenvironment, which delivers growth- and pro-survival signals and confers resistance to drugs. As for solid tumors, bone marrow (BM) angiogenesis is emerging as a critical component of MM development and progression, and hence as an attractive therapeutic target for the disease. The patho-physiology of MM associated angiogenesis is complex and involves a plethora of soluble factors, cellular players and mechanisms. Moreover, the hypoxic microenvironment inside the BM might significantly contribute to the induction and maintenance of a pro-angiogenic profile, given the well-known role of hypoxia in promoting angiogenesis in all its forms. Here we present an overview of the literature focusing on the mechanisms implicated in the "angiogenic switch", which corresponds to the transition from the avascular to the vascular phase of the disease. We also review evidence on the anti-angiogenic effects of PI and IMiDs, which substantially contribute to their anti-MM activity. Finally, we summarize possible caveats and perspectives about antiangiogenic strategies that could be addressed to improve the efficacy of treatments for MM patients.

Second-line treatment with intravenous gemcitabine and oral etoposide in platinum-resistant advanced ovarian cancer patients: results of a phase II study.

OBJECTIVE: The outcome of advanced ovarian cancer patients has not significantly improved since the introduction of platinum. One of the major reasons for this failure is the lack of an effective second-line treatment. In this phase II trial we tested the combination of gemcitabine and etoposide in 2 different groups of patients. Group 1 consisted of patients showing disease progression or relapse within 6 months of first-line platinum-based chemotherapy. Group 2 comprised heavily pretreated patients showing progression during the last chemotherapy attempt. METHODS: Thirty-four patients were enrolled. Gemcitabine was administered at a dose of 1,000 mg/m(2) on days 1 and 8 and etoposide was administered orally at 100 mg/day on days 8-12 for 6 courses. RESULTS: Eighteen patients (52.9%) had an objective response and the median duration of the response was 10.3 months. Our chemotherapy regimen showed a low toxicity and good patient compliance. In 5 patients the treatment had to be delayed and in only 2 patients it was discontinued. CONCLUSIONS: The combination of gemcitabine and oral etoposide seems to be a safe and effective second-line treatment for platinum-resistant ovarian cancer patients. Additional data on larger series are warranted to better define the activity of this combination regimen.