Comparative analyses of DNA extraction methods for whole blood quantification of HCMV DNAemia in patients with hematological diseases: false negative cases in manual method

Human cytomegalovirus (HCMV) DNA quantitation in whole blood (WB) by real-time or quantitative polymerase chain reaction (qPCR) is a highly sensitive and reproducible diagnostic procedure for monitoring HCMV DNAemia (DNAemia is the detection of DNA in samples of plasma, whole blood, isolated peripheral blood leukocytes or in buffy-coat specimens) in patients. We provided a comparative analysis of HCMV DNA extraction performance by two different techniques, one performed by an automated extractor and the other by a manual method. We observed that the automated extraction method allowed HCMV DNA detection in the presence of weak viremia while no differences are observed when the viral load is greater. Therefore, automated DNA extraction is a suitable and recommended protocol not only for early detection of HCMV infection but also for more accurate monitoring of HCMV DNAemia during post-therapy follow-up.

Modulation of Peripheral Immune Cell Subpopulations After RapidArc/Moderate Hypofractionated Radiotherapy for Localized Prostate Cancer: Findings and Comparison With 3D Conformal/Conventional Fractionation Treatment

Radiotherapy (RT) is an important therapeutic option in patients with localized prostate cancer (PC). Unfortunately, radiation treatment causes a decrease in peripheral lymphocytes and, consequently, influences the patients' immune status. Our aim was to study changes in peripheral blood immune cell subpopulations after RT and during 6 months' follow-up in 2 groups of PC patients irradiated with different techniques and dose fractions with curative intent. We also investigated the presence of correlation between immune cell modulation and genitourinary or gastrointestinal toxicity. We enrolled 44 patients treated with curative RT (RapidArc/hypofractionation regimen or 3D conformal/conventional fractionation) for localized PC. Total white blood cell (WBC), absolute lymphocyte counts (ALCs), and peripheral immune cell subpopulations were analyzed at baseline, at the end of RT, and 3 and 6 months after the end of RT. WBC and ALC greatly decreased at the end of RT with a trend to recover at 6 months' follow-up in the hypofractionation group but not in the conventional one. Furthermore, B, total T, T CD4+, T CD8+, and NK cell values dropped significantly in both groups at the end of RT, with a minor decrease detectable in the hypofractionation group for B, total T, and T CD4+ lymphocytes with respect to the other technique/fractionation group. Double-negative T (DNT), double-positive T (DPT), and NKT cells significantly decreased at the end of RT with a slight tendency to recover values during follow-up, particularly in the hypofractionation group. No correlation with genitourinary or gastrointestinal toxicity was found. In this study, we showed, for the first time, the effects of RapidArc/moderate hypofractionation RT on immune cell subsets in patients treated for localized PC. Due to the growing interest in minority T-cell subpopulations for immunotherapy, we also reported longitudinal monitoring of the effects of RT on DNT, DPT, and NKT, which was never studied before. Our preliminary data highlight the importance of considering the effects of different RT techniques/fractionation regimens on peripheral immune cells, in the era of RT and immunotherapy combination.

Abnormal cell-clearance and accumulation of autophagic vesicles in lymphocytes from patients affected with Ataxia-Teleangiectasia

Ataxia-Teleangiectasia (A-T) is a neurodegenerative disorder due to mutations in ATM gene. ATM in the nucleus ensures DNA repair, while its role in the cytosol is still poorly clarified. Abnormal autophagy has been documented in other neurodegenerative disorders, thus we evaluated whether alteration in this process may be involved in the pathogenesis of A-T by analyzing the autophagic vesicles and the genes implicated in the different stages of autophagy. Through transmission electron microscopy (TEM) and immunofluorescence analysis we observed an accumulation of APs associated with a LC3 puncta pattern, and a reduced number of ALs. We also documented an increased expression of genes involved in AP and lysosome biogenesis and function, and a decrease of Vps18 expression, involved in their vesicular trafficking and fusion. mTORC1-controlled proteins were hyperphosphorylated in A-T, in keeping with an increased mTOR inhibitory influence of autophagy. Betamethasone is able to promote the degradation of SQSTM1, a biomarker of autophagy. Collectively, our results indicate that in cells from A-T patients, the APs maturation is active, while the fusion between APs and lysosomes is inappropriate, thus implying abnormalities in the cell-clearance process. We also documented a positive effect of Betamethasone on molecules implicated in autophagosome degradation.

Myelodysplastic disorders carrying both isolated del(5q) and JAK2(V617F) mutation: concise review, with focus on lenalidomide therapy

The concomitant presence of del(5q) and JAK2(V617F) mutation is an infrequent event which occurs in rare patients with peculiar cytogenetic, molecular, morphological and clinical features, resembling those of both myelodysplastic syndromes and myeloproliferative neoplasms. Lenalidomide may induce rapid, profound, and long-lasting responses in a subset of these patients. However, the mechanism(s) by which the drug acts in these conditions remain not completely elucidated. A new case report and a review of all cases published so far in this setting are provided. Furthermore, the possibility of categorizing - from a clinical, pathological, and biological point of view - for at least some of these patients as a potential distinct entity is discussed.

Molecular evidence for a thymus-independent partial T cell development in a FOXN1-/- athymic human fetus

The thymus is the primary organ able to support T cell ontogeny, abrogated in FOXN1(-/-) human athymia. Although evidence indicates that in animal models T lymphocytes may differentiate at extrathymic sites, whether this process is really thymus-independent has still to be clarified. In an athymic FOXN1(-/-) fetus, in which we previously described a total blockage of CD4(+) and partial blockage of CD8(+) cell development, we investigated whether intestine could play a role as extrathymic site of T-lymphopoiesis in humans. We document the presence of few extrathymically developed T lymphocytes and the presence in the intestine of CD3(+) and CD8(+), but not of CD4(+) cells, a few of them exhibiting a CD45RA(+) naïve phenotype. The expression of CD3εεpTα, RAG1 and RAG2 transcripts in the intestine and TCR gene rearrangement was also documented, thus indicating that in humans the partial T cell ontogeny occurring at extrathymic sites is a thymus- and FOXN1-independent process.

Biological and clinical relevance of miRNA expression signatures in primary plasma cell leukemia

PURPOSE

Primary plasma cell leukemia (pPCL) is a rare and very aggressive form of plasma cell dyscrasia. To date, no information on microRNA (miRNA) expression in pPCL has been reported. This study aimed at investigating the involvement of miRNAs in pPCL and their possible relationship with higher tumor aggressiveness.

EXPERIMENTAL DESIGN

Global miRNA expression profiles were analyzed in highly purified malignant plasma cells from 18 pPCL untreated patients included in a prospective clinical trial. MiRNA expression patterns were evaluated in comparison with a representative series of multiple myeloma patients, in relation to the most recurrent chromosomal abnormalities (as assessed by fluorescence in situ hybridization and single-nucleotide polymorphism-array analysis), and in association with clinical outcome. MiRNA expression was also integrated with gene expression profiles in pPCL and multiple myeloma samples.

RESULTS

We identified a series of deregulated miRNAs in pPCL (42 upregulated and 41 downregulated) in comparison with multiple myeloma. Some of them, on the basis of their reported functions and putative target genes computed by integrative analysis, might have a role in the pathobiology of pPCL. As regards chromosomal aberrations, the expression of some miRNAs mapped to hotspot altered regions was associated with DNA copy number of the corresponding loci. Finally, 4 miRNA (miR-497, miR-106b, miR-181a*, and miR-181b) were identified as having expression levels that correlated with treatment response, and 4 (miR-92a, miR-330-3p, miR-22, and miR-146a) with clinical outcome.

CONCLUSIONS

Overall, our study provides insights into the possible contribution of miRNAs in the pathogenesis of pPCL and suggests targets for future therapeutic investigations.

Genome-wide analysis of primary plasma cell leukemia identifies recurrent imbalances associated with changes in transcriptional profiles

Primary plasma cell leukemia (pPCL) is a rare, yet aggressive form of de novo plasma cell tumor, distinct from secondary PCL (sPCL) which represents a leukemic transformation of pre-existing multiple myeloma (MM). Herein, we performed a comprehensive molecular analysis of a prospective series of pPCLs by means of FISH, single nucleotide polymorphism (SNP) array and gene expression profiling (GEP). IGH@ translocations were identified in 87% of pPCL cases, with prevalence of t(11;14) (40%) and t(14;16) (30.5%), whereas the most frequent numerical alterations involved 1p (38%), 1q (48%), 6q (29%), 8p (42%), 13q (74%), 14q (71%), 16q (53%), and 17p (35%). We identified a minimal biallelic deletion (1.5 Mb) in 8p21.2 encompassing the PPP2R2A gene, belonging to a family of putative tumor suppressors and found to be significantly down-regulated in deleted cases. Mutations of TP53 were identified in four cases, all but one associated with a monoallelic deletion of the gene, whereas activating mutations of the BRAF oncogene occurred in one case and were absent in N- and K-RAS. To evaluate the influence of allelic imbalances in transcriptional expression we performed an integrated genomic analysis with GEP data, showing a significant dosage effect of genes involved in transcription, translation, methyltransferase activity, apoptosis as well as Wnt and NF-kB signaling pathways. Overall, we provide a compendium of genomic alterations in a prospective series of pPCLs which may contribute to improve our understanding of the pathogenesis of this aggressive form of plasma cell dyscrasia and the mechanisms of tumor progression in MM.

Role of the common γ chain in cell cycle progression of human malignant cell lines

The γ-chain (γc) is a transducing element shared between several cytokine receptors whose alteration causes X-linked severe combined immunodeficiency. Recently, a direct involvement of γc in self-sufficient growth in a concentration-dependent manner was described, implying a direct relationship between the amount of the molecule and its role in cell cycle progression. In this study, we evaluate whether γc expression could interfere in cell cycle progression also in malignant hematopoietic cells. Here, we first report that in the absence of γc expression, lymphoblastoid B-cell lines (BCLs) die at a higher extent than control cells. This phenomenon is caspase-3 independent and is associated to a decreased expression of the antiapoptotic Bcl-2 family members. By contrast, increased expression of γc protein directly correlates with spontaneous cell growth in several malignant hematopoietic cell lines. We, also, find that the knockdown of γc protein through short interfering RNA is able to decrease the cell proliferation rate in these malignancies. Furthermore, an increased expression of all D-type cyclins is found in proliferating neoplastic cells. In addition, a direct correlation between the amount of γc and cyclins A2 and B1 expression is found. Hence, our data demonstrate that the amount of the γc is able to influence the transcription of genes involved in cell cycle progression, thus being directly involved in the regulatory control of cell proliferation of malignant hematopoietic cells.

Polymorphisms of the CYP1A1, CYP2E1 and XRCC1 genes and cancer risk in a Southern Italian population: a case-control study

BACKGROUND

Polymorphisms in genes encoding enzymes involved in xenobiotic metabolism and/or in cellular defenses against carcinogen-induced DNA damage play an important role in determining individual cancer susceptibility. However, their distribution and association with cancer susceptibility can vary in different populations.

MATERIALS AND METHODS

A case-control study including 290 cancer patients (cases) and 242 controls was performed to evaluate the relationship between polymorphisms of cytochrome P450 (CYP)1A1 and CYP2E1 and X-ray repair complementing defective repair in Chinese hamster cells (XRCC)1 genes and the risk of developing cancer in a Southern Italian (Basilicata) population. Genomic DNA was isolated from 5 ml whole blood and genotyping was performed using a PCR-RFLP technique.

RESULTS

No significant differences were observed in the distribution of the CYP1A1, CYP2E1 and XRCC1 gene polymorphisms between the cases and controls in the population under study.

CONCLUSION

The distribution of CYP1A1, CYP2E1 and XRCC1 gene polymorphisms in the Basilicata population is not different from that of other Italian regions or from that reported in the literature for Caucasian populations, and polymorphisms in these genes do not play an important role in determining cancer risk in the population under study.

Positive effects on hematopoiesis in patients with myelodysplastic syndrome receiving deferasirox as oral iron chelation therapy: a brief review

Iron overload is a frequent consequence in transfusion-dependent myelodysplastic syndromes (MDSs), which often requires iron chelation therapy (ICT). Interestingly, ICT may sometimes induce a hematologic improvement that leads to significant reduction or complete interruption of blood transfusions. This phenomenon has been recently described in MDS treated with the new oral chelator deferasirox. Here we briefly review the literature about this phenomenon and discuss the possible biological mechanisms underlying hematologic effects of deferasirox in MDS, starting from a new paradigmatic case in whom both hemoglobin level and platelet count improved, inducing transfusion-independence, soon after starting the treatment with deferasirox.

Development of a New Zirconia-Toughened Alumina: Promising Mechanical Properties and Absence of In Vitro Carcinogenicity

High purity alumina as well as zirconia ceramics have been widely used as orthopaedic implant biomaterials and dental devices displaying optimal, but sometimes exclusive, mechanical properties. In order to combine the advantages of alumina and zirconia ceramic materials different types of composites have been developed in which either zirconia is dispersed in an alumina matrix or vice versa. Orthopaedic and dental implant biomaterials are expected to be in contact with living tissues for a long period of time and their long term toxicity must be carefully evaluated. In this study we report the development of a high performance chromia-doped Zirconia Toughened Alumina (ZTA) material which displays promising mechanical properties in terms of hardness, strength and fracture toughness that make it suitable for prosthesis even for small joints. The long-term biocompatibility of this material was also evaluated, mainly in terms of DNA damage, mutagenicity and cancerogenetic potential in mammalian cells. The results obtained suggest that this new ZTA material does not display any long-term carcinogenic effect and it is suitable for biomedical applications from a cancerogenetic point of view. In conclusion, we report the development of a new chromia-doped ZTA material with interesting properties both from a mechanical and a biocompatibility point of view which warrant further studies on its suitability as a candidate biomaterial for orthopaedic implants and dental devices.

Differential toxic effects of methyl tertiary butyl ether and tert-butanol on rat fibroblasts in vitro

Methyl tertiary butyl ether (MTBE) is the most widely used motor vehicle fuel oxygenate since it reduces harmful emissions due to gasoline combustion. However, the significant increase in its use in recent years has raised new questions related to its potential toxicity. In fact, although available data are somehow conflicting, there is evidence that MTBE is a toxic substance that may have harmful effects on both animals and humans and an unresolved problem is the role played by MTBE metabolites, especially tertiary butyl alcohol (TBA), in determining toxic effects due to MTBE exposure. In this study, the toxic effects of MTBE have been analyzed on a normal diploid rat fibroblast cell line (Rat-1) and compared to the effects of TBA. The results obtained suggest that both MTBE and TBA inhibit cell growth in vitro but with different mechanisms in terms of effects on the cell cycle progression and on the modulation of cell cycle regulatory proteins. In fact, MTBE caused an accumulation of cells in the S-phase of the cell cycle, whereas TBA caused an accumulation in the G0/G1-phase with different effects on the expression of cyclin D1, p27Kip1, and p53. Moreover, both MTBE and TBA were also shown to induce DNA damage, as assessed in terms of oxidative DNA damage and nuclear DNA fragmentation, that appeared to be susceptible of repair by the cell DNA-repair machinery. In conclusion, these findings suggest that both MTBE and TBA can exert, by acting through different molecular mechanisms, important biological effects on fibroblasts in vitro. Further studies are warranted to shed light on the mechanisms responsible for the observed effects and on their potential significance for the in-vivo exposure.

GSTM1 and NAT2 polymorphisms and colon, lung and bladder cancer risk: a case-control study

BACKGROUND

Glutathione S-transferase M1 (GSTM1) and N-acetyltransferase-2 (NAT2) are phase II enzymes involved in the metabolism of xenobiotics and whose polymorphisms have been related to individual cancer risks.

PATIENTS AND METHODS

A case-control study was performed including 92 colon, 75 lung and 23 bladder cancer patients and 121 corresponding controls to verify the existence of an association between the main genetic polymorphisms of GSTM1 and NAT2 and the risk to develop cancer. Genomic DNA, isolated from 5 mL whole blood, was used to study GSTM1 and NAT2 polymorphisms using multiplex PCR and a PCR-RFLP technique, respectively.

RESULTS

GSTM1 homozygous null genotype was associated with an increased risk of colon cancer, especially in females and in younger patients. For NAT2 gene, the results suggest a role for the low acetylator phenotype in the development of colon and lung cancer, especially in females. In bladder cancer patients two rare NAT2 genotypes were found at a higher frequency compared with all the other groups.

CONCLUSION

The results do not suggest a different distribution of GSTM1 and NAT2 polymorphisms in the studied population compared to those reported for other Caucasian populations and warrant further studies in order to evaluate their potential relationship with individual cancer risks.

Polymorphisms of the DNA repair genes XRCC1 and XRCC3 and risk of lung and colorectal cancer: a case-control study in a Southern Italian population

BACKGROUND

Genetic polymorphisms in DNA repair genes may influence individual variation in DNA repair capacity, which may be associated with a higher risk of developing cancer. Studies on the association between DNA repair gene polymorphisms and lung and colorectal cancer risk appear to be very limited. This study was designed to examine the polymorphisms associated with two DNA repair genes, namely XRCC1 Arg194Trp, XRCC1 Arg399Gln and XRCC3 Thr241Met, and to investigate their role as susceptibility markers for lung and colorectal cancer.

MATERIALS AND METHODS

A case-control study was conducted including 94 and 109 cases of lung and colorectal cancer, respectively, and 121 hospital-based age- and sex-matched healthy controls to examine the role of XRCC1 and XRCC3 genetic polymorphisms in the context of lung and colorectal cancer risk for a Southern Italian population. Genomic DNA isolated from 5 ml whole blood was used to genotype XRCC1 Arg194Trp, XRCC1 Arg399Gln and XRCC3 Thr241Met by means of polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis.

RESULTS

No differences were observed among the studied groups with regard to the genotype distribution of XRCC1 codon 194 and 399, thus the risk for lung and colorectal cancer did not appear to be significantly influenced by polymorphisms of this gene. Significant differences were observed among the studied groups with regard to the genotype distribution of XRCC3 codon 241. In particular, the XRCC3 241Met allele was associated with an increased risk of lung and colorectal cancer.

CONCLUSION

Our results showed no evidence of a relationship between the XRCC1 Arg194Trp and Arg399Gln polymorphisms and the risk of lung and colorectal cancer. On the other hand, they suggested an increased risk in individuals with the XRCC3 Thr241Met polymorphism thus warranting further study to definitively evaluate the role of DNA repair mechanisms in colorectal and lung cancer susceptibility.

Targeted inhibition of the epidermal growth factor receptor-tyrosine kinase by ZD1839 (?Iressa?) induces cell-cycle arrest and inhibits proliferation in prostate cancer cells

The epidermal growth factor (EGF) plays a role in the development of prostate cancer, which becomes essential after androgen resistance has emerged. The EGF receptor (EGFR) is therefore a potential target for anticancer therapy. We evaluated the effects of ZD1839 ('Iressa'), an orally active EGFR-tyrosine kinase inhibitor, on prostate cancer cell lines. The effects of ZD1839 were evaluated on the anchorage dependent and independent growth of androgen-responsive (LNCaP) and androgen-independent (DU145 and PC3) cells by a cell proliferation assay, cell counting, and soft agar analysis. Flow cytometric analysis and Western blotting were used to assess the effects on the cell-cycle and on protein expression levels, respectively. ZD1839 caused a dose- and time-dependent growth inhibition in all three cell lines. A dose-dependent supra-additive increase in growth inhibition was observed when ZD1839 was combined with the antiandrogen flutamide or ionizing radiation (IR). The antiproliferative effect of ZD1839 was mainly cytostatic and associated with a block in the G(0)/G(1) phase of the cell-cycle, evident after about 12 h of treatment. In the DU145 cells this block was associated with an increase in expression of the CDK inhibitor p27(Kip1), both in the cytoplasmic and nuclear fractions. The increase in p27(Kip1) was not evident in the LNCaP and PC3 cells. No changes were observed in the expression of cyclin D1 protein. These results demonstrate the antiproliferative effects of ZD1839 on the growth of prostate cancer cells and suggest that inhibition of EGFR-associated signal transduction pathway might represent a promising novel therapeutic strategy for the treatment of prostate cancer.

Increased expression of cyclin E is associated with an increased resistance to doxorubicin in rat fibroblasts

Cell cycle progression in eukaryotic cells is regulated by a family of cyclin-dependent kinases (CDKs). Cyclin E is a regulatory subunit of CDK2 and drives cells from G1 to S phase. Increased expression of cyclin E is a frequent event in human malignancies and has been associated with poor prognosis in various cancers. In this study, we evaluated the effects of cyclin E-overexpression on the sensitivity of rat fibroblasts to anticancer drugs. Cyclin E-overexpressing cells were less sensitive to doxorubicin-induced inhibition of cell growth but not to other antineoplastic drugs, such as paclitaxel, vincristine, etoposide and methotrexate. Cyclin E-overexpressing fibroblasts also displayed a reduction in ROS levels and a significantly lower increase following doxorubicin treatment compared with vector control cells. The expression of manganese superoxide dismutase (MnSOD) and its activity were increased (about 1.3-fold) in cyclin E-overexpressing derivatives compared with control cells. These results suggest that cyclin E overexpression might reduce tumour cells sensitivity to doxorubicin by affecting the expression of MnSOD and that determination of cyclin E expression levels might help to select patients to be treated with an anthracycline-based antineoplastic therapy.