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1.
Sensors (Basel) ; 22(13)2022 Jun 29.
Article in English | MEDLINE | ID: mdl-35808429

ABSTRACT

Complex energy monitoring and control systems have been widely studied as the related topics include different approaches, advanced sensors, and technologies applied to a strongly varying amount of application fields. This paper is a systematic review of what has been done regarding energy metering system issues about (i) sensors, (ii) the choice of their technology and their characterization depending on the application fields, (iii) advanced measurement approaches and methodologies, and (iv) the setup of energy Key Performance Indicators (KPIs). The paper provides models about KPI estimation, by highlighting design criteria of complex energy networks. The proposed study is carried out to give useful elements to build models and to simulate in detail energy systems for performance prediction purposes. Some examples of energy complex KPIs based on the integration of the Artificial Intelligence (AI) concept and on basic KPIs or variables are provided in order to define innovative formulation criteria depending on the application field. The proposed examples highlight how modeling a complex KPI as a function of basic variables or KPIs is possible, by means of graph models of architectures.


Subject(s)
Artificial Intelligence , Quality Indicators, Health Care , Technology
2.
Antioxidants (Basel) ; 10(12)2021 Dec 15.
Article in English | MEDLINE | ID: mdl-34943102

ABSTRACT

Tomato (Solanum lycopersicum L.) is one of the most consumed vegetables worldwide due to its low caloric intake and high fiber, minerals, and phenolic compounds, making it a high-quality functional food. However, fruit quality attributes can be affected by pre-harvest factors, especially environmental stresses. This research aimed to evaluate the influence of two shading nets (white net -30% and pearl grey net -40% shading degree) on the yield and phytochemical profile of tomato fruits grown in summer under the Mediterranean climate. Mineral and organic acid content (by ion chromatography-IC), phenolic profile (by ultra-high performance liquid chromatography-UHPLC coupled with an Orbitrap high-resolution mass spectrometry-HRMS), carotenoid content (by high-performance liquid chromatography with diode array detection-HPLC-DAD), and antioxidant activities DPPH, ABTS, and FRAP (by UV-VIS spectrophotometry) were determined. Tomato fruits grown under the pearl grey net recorded the highest values of total phenolic compounds (14,997 µg 100 g-1 of fresh weight) and antioxidant activities DPPH, ABTS, and FRAP, without affecting either fruit color or marketable yield. The reduction of solar radiation through pearl grey nets proved to be an excellent tool to increase the phytochemical quality of tomato fruits during summer cultivation in a Mediterranean environment.

3.
Plants (Basel) ; 9(10)2020 Sep 24.
Article in English | MEDLINE | ID: mdl-32987968

ABSTRACT

In a global climate change environment, assuring optimal growing conditions is a difficult challenge, compromising the food supply for a rapidly rising population. The climatic conditions in the protected environment lead to high temperatures and fast insect development, impacting productivity and vegetables qualitative attributes. Consumers' interest in healthy food requires sustainable tools to manage biotic and abiotic factors and, from this perspective, anti-insect nets represent an excellent "green" solution. For this purpose, our goal was to compare two different anti-insect nets on microclimate, production, and qualitative traits of Cucurbita pepo L. fresh fruits. The experiment was conducted in three separate polyethylene high tunnels, with 50 mesh anti-insect nets of different porosities being installed on the openings of two tunnels, while the third tunnel was a control without nets. Microclimate measurements, as well as yield, physiological, and phytochemicals variables, were assessed. The 50 mesh net led to a decrease in marketable yield (22.5%), fruit number (18.0%), CO2 net assimilation rate (6.0%), and transpiration rate (29.5%). Total soluble solids, antioxidant activities and total ascorbic acid concentration had an opposite trend. The 50 mesh AirPlus net improved quality aspects of zucchini fruits by increasing total ascorbic acid, total phenols, and antioxidant compounds, with no negative impact on yield.

4.
J Interferon Cytokine Res ; 33(6): 308-18, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23421371

ABSTRACT

It is well known that ionizing radiations induce a marked downregulation of antigen-dependent and natural immunity for a prolonged period of time. This is due, at least in part, to radiation-induced apoptosis of different lymphocyte subpopulations, including natural killer (NK) cells. Aim of this study was to investigate the capability of Beta Interferon (ß-IFN) and Interleukin-2 (IL2), alone or in combination, to restore the functional activity of the natural immune system. Mononuclear cells (MNCs) obtained from intact or in vitro irradiated human peripheral blood were treated in vitro with ß-IFN immediately before or at the end of the 4-day treatment with IL2. Time-course analysis was performed on the NK activity, the total number and the apoptotic fraction of CD16+ and CD56+ cells, the 2 main NK effector cell subpopulations. The results indicate that radiation-induced impairment of natural cytotoxicity of MNC could be successfully antagonized by the ß-IFN+IL2 combination, mainly when exposure to ß-IFN preceded IL2 treatment. This radioprotective effect is paralleled by lower levels of radiation-induced apoptosis and increased expression of the antiapoptotic Bcl-2 protein. Since natural immunity can play a significant role in antitumor host's resistance, these results could provide the rational basis for a cytokine-based pharmacological strategy able to restore immune responsiveness and to afford possible therapeutic benefits in cancer patients undergoing radiotherapy.


Subject(s)
Cytotoxicity, Immunologic/drug effects , Cytotoxicity, Immunologic/radiation effects , Immunity, Innate/drug effects , Immunity, Innate/radiation effects , Interferon-beta/pharmacology , Interleukin-2/pharmacology , Apoptosis/drug effects , Apoptosis/immunology , Apoptosis/radiation effects , CD56 Antigen/immunology , Cell Line, Tumor , Cytotoxicity, Immunologic/immunology , GPI-Linked Proteins/immunology , Gamma Rays , Humans , Immunity, Innate/immunology , Interferon-beta/immunology , Interleukin-2/immunology , K562 Cells , Killer Cells, Natural/drug effects , Killer Cells, Natural/immunology , Killer Cells, Natural/radiation effects , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/radiation effects , Lymphocyte Subsets/drug effects , Lymphocyte Subsets/immunology , Lymphocyte Subsets/radiation effects , Proto-Oncogene Proteins c-bcl-2/immunology , Receptors, IgG/immunology
5.
PLoS One ; 7(2): e31467, 2012.
Article in English | MEDLINE | ID: mdl-22328933

ABSTRACT

An increasing number of malignancies has been shown to be initiated and propelled by small subpopulations of cancer stem cells (CSC). However, whether tumor aggressiveness is driven by CSC and by what extent this property may be relevant within the tumor mass is still unsettled. To address this issue, we isolated a rare tumor cell population on the basis of its CD44(+)CD24(-) phenotype from the human androgen-independent prostate carcinoma cell line DU145 and established its CSC properties. The behavior of selected CSC was investigated with respect to the bulk DU145 cells. The injection of CSC in nude mice generated highly vascularized tumors infiltrating the adjacent tissues, showing high density of neuroendocrine cells and expressing low levels of E-cadherin and ß-catenin as well as high levels of vimentin. On the contrary, when a comparable number of unsorted DU145 cells were injected the resulting tumors were less aggressive. To investigate the different features of tumors in vivo, the influence of differentiated tumor cells on CSC was examined in vitro by growing CSC in the absence or presence of conditioned medium from DU145 cells. CSC grown in permissive conditions differentiated into cell populations with features similar to those of cells held in aggressive tumors generated from CSC injection. Differently, conditioned medium induced CSC to differentiate into a cell phenotype comparable to cells of scarcely aggressive tumors originated from bulk DU145 cell injection. These findings show for the first time that CSC are able to generate differentiated cells expressing either highly or scarcely aggressive phenotype, thus influencing prostate cancer progression. The fate of CSC was determined by signals released from tumor environment. Moreover, using microarray analysis we selected some molecules which could be involved in this cell-to-cell signaling, hypothesizing their potential value for prognostic or therapeutic applications.


Subject(s)
Cell Communication/physiology , Neoplastic Stem Cells/pathology , Prostatic Neoplasms/pathology , Animals , CD24 Antigen/metabolism , Cadherins/metabolism , Cell Differentiation/physiology , Cell Line, Tumor , Humans , Hyaluronan Receptors/metabolism , Male , Mice , Mice, SCID , Neoplastic Stem Cells/metabolism , Oligonucleotide Array Sequence Analysis , Prostatic Neoplasms/metabolism , Transplantation, Heterologous , beta Catenin/metabolism
6.
J Biol Chem ; 285(19): 14160-9, 2010 May 07.
Article in English | MEDLINE | ID: mdl-20223820

ABSTRACT

Mitogen-activated protein kinase kinase 3 (MAP2K3) is a member of the dual specificity kinase group. Growing evidence links MAP2K3 to invasion and tumor progression. Here, we identify MAP2K3 as a transcriptional target of endogenous gain-of-function p53 mutants R273H, R175H, and R280K. We show that MAP2K3 modulation occurred at the mRNA and protein levels and that endogenous mutant p53 proteins are capable of binding to and activate the MAP2K3 promoter. In addition, we found that the studied p53 mutants regulate MAP2K3 gene expression through the involvement of the transcriptional cofactors NF-Y and NF-kappaB. Finally, functional studies showed that endogenous MAP2K3 knockdown inhibits proliferation and survival of human tumor cells, whereas the ectopic expression of MAP2K3 can rescue the proliferative defect induced by mutant p53 knockdown. Taken together, our findings define a novel player through which mutant p53 exerts its gain-of-function activity in cancer cells.


Subject(s)
Gene Expression Regulation, Neoplastic , MAP Kinase Kinase 3/genetics , Mutation/genetics , Neoplasms/genetics , Tumor Suppressor Protein p53/genetics , Blotting, Western , Cell Line, Tumor , Cell Proliferation , Chromatin Immunoprecipitation , Flow Cytometry , Humans , MAP Kinase Kinase 3/antagonists & inhibitors , MAP Kinase Kinase 3/metabolism , Mutant Proteins/genetics , Mutant Proteins/metabolism , NF-kappa B/genetics , NF-kappa B/metabolism , Neoplasms/pathology , Promoter Regions, Genetic/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA, Small Interfering/pharmacology , Reverse Transcriptase Polymerase Chain Reaction , Transcriptional Activation , Up-Regulation
7.
Free Radic Biol Med ; 48(10): 1338-46, 2010 May 15.
Article in English | MEDLINE | ID: mdl-20171273

ABSTRACT

HIPK2 is a stress-induced kinase and a transcriptional corepressor that functionally cooperates with p53 to suppress cancer. Activation of the p53 proapoptotic function requires a cascade of phosphorylations and acetylations, and HIPK2 takes part in both modifications in that it phosphorylates p53 Ser46 and induces p53 Lys382 acetylation. Here, to further investigate the role of HIPK2 in p53 activation, we started with the finding that HIPK2 inhibition upregulated Nox1, a homolog of the catalytic subunit of the superoxide-generating NADPH oxidase, involved in tumor progression and ROS production. We found that Nox1 inhibited p53 Lys382 acetylation, which is a target of SIRT1 deacetylase, and impaired p53 proapoptotic transcriptional activity. By the use of either small interfering RNAs to target SIRT1 or the SIRT1 inhibitor nicotinamide we found that Nox1-dependent inhibition of p53 transcriptional activity was SIRT1-dependent. Thus, Nox1 was unable to inhibit p53 when coexpressed with a SIRT1 deacetylase-defective mutant (SIRT1HY), suggesting a link between Nox1 and SIRT1 activity. Finally, recovery of HIPK2 function downregulated Nox1 expression with rescue of p53 Lys382 acetylation and p53 activity. Together, our findings indicate that Nox1 upregulation may activate SIRT1 and inhibit p53 and that Lys382 is important for p53 proapoptotic function.


Subject(s)
Breast Neoplasms/metabolism , Carcinoma/metabolism , Colonic Neoplasms/metabolism , Lung Neoplasms/metabolism , NADPH Oxidases/biosynthesis , Tumor Suppressor Protein p53/metabolism , Acetylation/drug effects , Apoptosis/drug effects , Apoptosis/genetics , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Carcinoma/genetics , Carcinoma/pathology , Carrier Proteins/biosynthesis , Carrier Proteins/genetics , Cell Line, Tumor , Cloning, Molecular , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Female , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Mutant Proteins/genetics , Mutant Proteins/metabolism , NADPH Oxidase 1 , NADPH Oxidases/genetics , Niacinamide/pharmacology , Protein Serine-Threonine Kinases/biosynthesis , Protein Serine-Threonine Kinases/genetics , RNA, Small Interfering/genetics , Sirtuin 1/antagonists & inhibitors , Sirtuin 1/genetics , Sirtuin 1/metabolism , Transcriptional Activation/drug effects , Transcriptional Activation/genetics , Tumor Suppressor Protein p53/genetics
8.
Pharmacol Res ; 61(5): 437-48, 2010 May.
Article in English | MEDLINE | ID: mdl-20026273

ABSTRACT

PHA-848125 is a novel cyclin-dependent kinase inhibitor under Phase I/II clinical investigation. In this study, we describe, for the first time, the effect of PHA-848125 on human melanoma cells in vitro. Seven melanoma cell lines with different sensitivity to temozolomide (TMZ) were exposed to PHA-848125 for 5 days and then assayed for cell growth. In all cases, including TMZ-resistant cells, PHA-848125 IC(50) values were significantly below the maximum plasma concentrations achievable in the clinic. In the most PHA-848125-sensitive cell line, the drug caused a concentration-dependent G(1) arrest. PHA-848125 also impaired phosphorylation of the retinoblastoma protein at CDK2 and CDK4 specific sites, decreased retinoblastoma protein and cyclin A levels, and increased p21(Cip1), p27(Kip1) and p53 expression. Combined treatment with fixed ratios of TMZ plus PHA-848125 was studied in three melanoma cell lines. PHA-848125 was added to the cells 48 h after TMZ and cell growth was evaluated after 3 additional days of culture. Parallel experiments were performed in the presence of O(6)-benzylguanine (BG), to prevent repair of methyl adducts at O(6)-guanine induced by TMZ. Drug combination of TMZ plus BG and PHA-848125 produced additive or synergistic effects on cell growth, depending on the cell line. In the absence of BG, the combination was still more active than the single agents in the cell line moderately sensitive to TMZ, but comparable to PHA-848125 alone in the two TMZ-resistant cell lines. When TMZ plus BG were used in combination with PHA-848125 against cultured normal melanocytes, neither synergistic nor additive antiproliferative effects were observed. Our results indicate that PHA-848125 can have a therapeutic potential in melanoma patients, alone or combined with TMZ. Moreover this agent appears to be particularly attractive on the bases of its effectiveness against TMZ-resistant melanoma cells.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Cyclin-Dependent Kinases/antagonists & inhibitors , Dacarbazine/analogs & derivatives , Enzyme Inhibitors/pharmacology , Melanoma/drug therapy , Pyrazoles/pharmacology , Quinazolines/pharmacology , Apoptosis/drug effects , Blotting, Western , Cell Cycle/drug effects , Cell Line, Tumor , Cell Proliferation/drug effects , Coloring Agents , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/metabolism , DNA Mutational Analysis , Dacarbazine/pharmacology , Drug Resistance, Neoplasm/drug effects , Drug Synergism , Genes, p53/genetics , Humans , Melanoma/pathology , O(6)-Methylguanine-DNA Methyltransferase/metabolism , Temozolomide , Tetrazolium Salts , Thiazoles
9.
J Cell Physiol ; 220(1): 35-44, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19347870

ABSTRACT

In previous studies on HeLa cells we demonstrated estrogen-responsiveness of the epidermal growth factor receptor (EGFR) gene, as 17beta-estradiol (E(2)) and selective estrogen receptor modulators (SERMs) genistein (G), daidzein (D), and 4-hydroxytamoxifen (4OH-T) modulated its transcription in a ligand- and estrogen receptor (ER) isoform-specific way. This study describes further investigations into the role of ERs in mediating the effects induced by E(2) and SERMs on EGFR expression, and the relationship between the actions of ERs and EGFR in U2OS osteosarcoma cells stably expressing ERalpha or ERbeta. Cell number and DNA content determination revealed that E(2), G, and D inhibited proliferation and cell cycle progression and promoted apoptosis in both cell lines. In parallel, changes in cell morphology typical of osteoblast maturation were observed via optical microscopy. Consistently, quantitative PCR and Western blot analysis showed an up-regulation of markers of osteoblast differentiation and bone repair, and a decrease in EGFR expression. The transfection of specific antisense (AS) oligonucleotides strengthened our hypothesis that EGFR reduction caused changes in the proliferation/differentiation pattern comparable to those induced by ER ligands. The link between the ER and EGFR pathways was confirmed by treatment with 4OH-T, which decreased the EGFR level and produced differentiation effects via ERalpha, but induced both EGFR expression and proliferation effects via ERbeta. In conclusion, we show that also in U2OS cells, E(2) and SERMs are able to modulate the expression of the EGFR gene and can affect events strictly controlled by its signaling pathway, such as the maturation of osteoblasts.


Subject(s)
Cell Differentiation/drug effects , ErbB Receptors/drug effects , Estradiol/metabolism , Osteoblasts/drug effects , Osteosarcoma/metabolism , Phytoestrogens/pharmacology , Selective Estrogen Receptor Modulators/pharmacology , Apoptosis/drug effects , Biomarkers/metabolism , Cell Cycle/drug effects , Cell Differentiation/genetics , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Shape/drug effects , Down-Regulation , ErbB Receptors/genetics , ErbB Receptors/metabolism , Estrogen Receptor alpha/drug effects , Estrogen Receptor alpha/metabolism , Estrogen Receptor beta/drug effects , Estrogen Receptor beta/metabolism , Genistein/pharmacology , Humans , Isoflavones/pharmacology , Osteoblasts/metabolism , Osteoblasts/pathology , Osteosarcoma/genetics , Osteosarcoma/pathology , RNA, Messenger/metabolism , Tamoxifen/analogs & derivatives , Tamoxifen/pharmacology , Time Factors
10.
Mol Pharmacol ; 74(1): 173-83, 2008 Jul.
Article in English | MEDLINE | ID: mdl-18413665

ABSTRACT

The phosphatidylinositol 3-kinase/AKT pathway is activated frequently in human cancer, and it has been implicated in tumor cell proliferation, survival, and chemoresistance. In this study, we addressed the role of AKT in cellular responses to the therapeutic methylating agent temozolomide (TMZ), and we investigated the possible link between TMZ-induced modulation of AKT function and activation of ataxia-telangiectasia and Rad3-related (ATR)- and ataxia telangiectasia mutated (ATM)-dependent signaling pathways. We found that clinically relevant concentrations of TMZ caused activation of endogenous AKT in lymphoblastoid cells, and in colon and breast cancer cells, and that this molecular event required a functional mismatch repair system. Transfection of a dominant-negative kinase-dead form of AKT1 into breast cancer cells abrogated TMZ-induced activation of endogenous AKT, and it markedly enhanced cell sensitivity to the drug. Likewise, exposure of the MMR-proficient cell lines to the AKT inhibitor D-3-deoxy-2-O-methyl-myo inositol 1-[(R)-2-methoxy-3-(octadecyloxy)-propyl hydrogen phosphate] (SH-5) impaired AKT phosphorylation in response to TMZ, and it significantly increased cell chemosensitivity. Furthermore, small interfering RNA (siRNA)-mediated reduction of AKT1 expression in colon cancer cells potentiated the growth inhibitory effects of TMZ. Inhibition of ATM expression in colon cancer cells by siRNA did not impair TMZ-induced activation of AKT, whereas siRNA-mediated inhibition of ATR prevented AKT activation in response to the drug and increased cell chemosensitivity. These results strongly support the hypothesis that clinical benefit could be obtained by combining TMZ with inhibitors of the AKT pathway. Moreover, they provide the first evidence of a novel function of ATR as an upstream activator of AKT in response to DNA damage induced by O(6)-guanine-methylating agents.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Cell Cycle Proteins/metabolism , Cell Proliferation/drug effects , Dacarbazine/analogs & derivatives , Proto-Oncogene Proteins c-akt/metabolism , Ataxia Telangiectasia Mutated Proteins , B-Lymphocytes/physiology , Breast Neoplasms/pathology , Carcinoma/pathology , Cell Cycle Proteins/genetics , Cell Line , Cell Line, Tumor , Dacarbazine/pharmacology , Female , HCT116 Cells , Humans , Protein Serine-Threonine Kinases , Proto-Oncogene Proteins c-akt/genetics , Temozolomide
11.
J Cell Physiol ; 212(1): 118-25, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17348035

ABSTRACT

The viral factor E7 plays a key role in the well-established association between "high-risk" Human Papillomavirus (HPV) infection and the development of epithelial malignant tumors, as uterine cervix and ano-genital cancer. To delve into the molecular mechanisms of HPV-mediated cell transformation, we searched for novel potential cellular targets of the HPV-16 E7 oncoprotein, by means of the yeast two-hybrid technique, identifying a protein-protein interaction between HPV-16 E7 and the pro-apoptotic cellular factor Siva-1. Using co-precipitation assays and the "PepSets" technique, we confirmed this physical interaction and mapped accurately, for both proteins, the amino acid residues involved. Additionally, we found that HPV-16 E7 competed in vitro with the binding of the Bcl-X(L) anti-apoptotic factor to Siva-1, an interaction that has a major inference in UV radiation-induced apoptosis. In HaCaT immortalized human keratinocytes, forced HPV-16 E7 expression by retroviral infection caused Siva-1 transcript up-regulation, detected by cDNA macroarray hybridization and real-time quantitative PCR, paralleled by an increased amount of protein. Confirming the anti-apoptotic role of HPV-16 E7 in the HaCaT cellular model, evaluated by nuclear morphology, we also found that Siva-1 expression produced a significant increase of the apoptotic rate in UV radiation-exposed HaCaT cells, and that this effect resulted explicitly counteracted by HPV-16 E7. Being apoptosis a key physiological process for the elimination of irreversibly injured cells, the anti-apoptotic role of HPV-16 E7, performed at least by its interference with Siva-1, can be considered an additional mechanism for the survival of damaged, potentially transforming, cell clones.


Subject(s)
Intracellular Signaling Peptides and Proteins/metabolism , Keratinocytes/metabolism , Oncogene Proteins, Viral/metabolism , Apoptosis/physiology , Apoptosis Regulatory Proteins , Cell Line , Gene Library , Humans , Papillomavirus E7 Proteins , Protein Binding , bcl-X Protein/metabolism
12.
Blood ; 106(10): 3507-14, 2005 Nov 15.
Article in English | MEDLINE | ID: mdl-16099883

ABSTRACT

Our recent results on autocrine nerve growth factor (NGF) synthesis in B lymphocytes, which directly regulates the expression and release of calcitonin gene-related peptide (CGRP), a neuropeptide known to down-regulate immune response, led us to propose an anti-inflammatory action of NGF. In the present work, we investigated whether the endogenous synthesis of NGF can regulate the expression of CGRP in other antigen-presenting cells, such as monocytes, and whether this may have a functional effect. Our data indicate that human monocytes synthesize basal levels of NGF and CGRP and that, following lipopolysaccharide (LPS) stimulation, NGF and CGRP expression are both up-regulated. When endogenous NGF is neutralized, the up-regulation of CGRP expression induced by LPS is inhibited. The expression of membrane molecules involved in T-cell activation such as human leukocyte antigen-DR (HLA-DR) and CD86 is affected by endogenous NGF, and similar effects were obtained using a CGRP(1) receptor antagonist. In addition, NGF deprivation in LPS-treated monocytes significantly decreases interleukin 10 (IL-10) synthesis. Our findings indicate that endogenous NGF synthesis has a functional role and may represent a physiologic mechanism to down-regulate major histocompatibility complex (MHC) class II and CD86 expression and alter the development of immune responses.


Subject(s)
B7-2 Antigen/biosynthesis , Calcitonin Gene-Related Peptide/biosynthesis , HLA-DR Antigens/biosynthesis , Interleukin-10/biosynthesis , Monocytes/immunology , Nerve Growth Factor/immunology , Up-Regulation/immunology , B-Lymphocytes/immunology , B7-2 Antigen/immunology , Calcitonin Gene-Related Peptide/immunology , Calcitonin Gene-Related Peptide Receptor Antagonists , Cells, Cultured , HLA-DR Antigens/immunology , Humans , Interleukin-10/immunology , Lipopolysaccharides/pharmacology , Monocytes/cytology , Up-Regulation/drug effects
13.
J Virol Methods ; 126(1-2): 91-100, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15847924

ABSTRACT

The present study describes the phenotypic and genotypic features of seven individual growth transformed, euploid-diploid EBV+ human B cell lines arisen spontaneously in vitro. The lines, obtained under general and standard culture conditions (un-manipulated), from seven individual bone marrow samples of 18 healthy young adults, Caucasian, of both sexes, display many traits of normal B cells and represent a mixture of EBV infected latently (latency type III) and producer cells (5-16% VCA+ by immunofluorescence) releasing seven individual different viral strains [Fruscalzo et al., 2001. DNA sequence heterogeneity within the Epstein-Barr virus family of repeats in the latent origin of replication. Gene 265, 165-173] similar to the B95-8 genotype as shown by results of Southern blot of BamHI-digested DNA fragment. These tests were planned to characterize more fully this panel of new bone marrow cell lines sharing normal B cell traits.


Subject(s)
B-Lymphocytes/cytology , B-Lymphocytes/virology , Bone Marrow Cells/cytology , Cell Line, Transformed , Herpesvirus 4, Human/genetics , Virus Latency , B-Lymphocytes/immunology , Cell Cycle , Cell Proliferation , Cell Transformation, Viral , Female , Gene Expression , Gene Rearrangement, B-Lymphocyte , Genome, Viral , Humans , Male , RNA, Messenger/analysis , RNA, Viral/analysis
14.
J Cell Physiol ; 202(3): 922-8, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15389561

ABSTRACT

The cell cycle regulatory pathway responsible for the control of the late-G1 checkpoint is found recurrently altered in human malignant melanoma, often due to lack of functional p16 or pRb (pRb-1) proteins. Here we examined the ability of p16-derived peptides to mimic p16 function in two exemplary human melanoma cell lines: the p16-defective, pRb-positive A375M cells and p16-positive, pRb-defective A2058 cells. The synthetic p16-mimicking peptides strongly induced apoptosis in p16-, pRb+ A375M cells in vitro, while they had significantly less activity on p16+, pRb- A2058 cells. The most active p16-mimicking peptide, p16-AP9, also potently inhibited in vivo growth of the A375M melanoma. Treated tumors showed a threefold smaller volume (P < 0.025) and a significant reduction of the mitotic index and of PCNA expression. Growth of A2058 cells in vivo was not affected by treatment with the p16-mimicking peptide. Our results demonstrate that p16-mimicking peptides can induce apoptosis in vitro and that can inhibit tumor growth in vivo in p16-defective, pRb-expressing human melanoma cells, suggesting that p16-mimicking peptides can represent a promising tool for targeted therapy in selected cancer phenotypes.


Subject(s)
Cell Cycle/physiology , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Melanoma/metabolism , Neoplasms/metabolism , Peptides/metabolism , Retinoblastoma Protein/metabolism , Amino Acid Sequence , Apoptosis , Cell Line, Tumor , Cyclin-Dependent Kinase Inhibitor p16/genetics , Down-Regulation , Humans , Molecular Sequence Data , Peptides/genetics , Phosphorylation , Retinoblastoma Protein/genetics , Tumor Suppressor Protein p53/metabolism
15.
Mol Pharmacol ; 66(3): 478-91, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15322239

ABSTRACT

The mammalian mismatch repair (MMR) system has been implicated in activation of the G(2) checkpoint induced by methylating agents. In an attempt to identify the signaling events accompanying this phenomenon, we studied the response of MMR-proficient and -deficient cells to treatment with the methylating agent temozolomide (TMZ). At low TMZ concentrations, MMR-proficient cells were growth-inhibited, arrested in G(2)/M, and proceeded to apoptosis after the second post-treatment cell cycle. These events were accompanied by activation of the ATM and ATR kinases, and phosphorylation of Chk1, Chk2, and p53. ATM was activated later than ATR and was dispensable for phosphorylation of Chk1, Chk2, and p53 on Ser15 and for triggering of the G(2)/M arrest. However, it conferred protection against cell growth inhibition induced by TMZ. ATR was activated earlier than ATM and was required for an efficient phosphorylation of Chk1 and p53 on Ser15. Moreover, abrogation of ATR function attenuated the TMZ-induced G(2)/M arrest and increased drug-induced cytotoxicity. Treatment of MMR-deficient cells with low TMZ concentrations failed to activate ATM and ATR and to cause phosphorylation of Chk1, Chk2, and p53, as well as G(2)/M arrest and apoptosis. However, all these events occurred in MMR-deficient cells exposed to high TMZ concentrations, albeit with faster kinetics. These results demonstrate that TMZ treatment activates ATM- and ATR-dependent signaling pathways and that this process is absolutely dependent on functional MMR only at low drug concentrations.


Subject(s)
Antineoplastic Agents, Alkylating/pharmacology , Apoptosis , Cell Cycle Proteins/metabolism , DNA Damage/drug effects , Dacarbazine/analogs & derivatives , Dacarbazine/pharmacology , Protein Serine-Threonine Kinases/metabolism , Ataxia Telangiectasia Mutated Proteins , Base Pair Mismatch , Cell Cycle/drug effects , Cell Division/drug effects , Checkpoint Kinase 1 , Checkpoint Kinase 2 , DNA Repair/drug effects , DNA-Binding Proteins , Humans , Phosphorylation/drug effects , Protein Kinases/metabolism , Serine/metabolism , Temozolomide , Time Factors , Tumor Cells, Cultured , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Proteins
16.
J Neuroimmunol ; 136(1-2): 130-9, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12620652

ABSTRACT

In this study, we investigated whether hematopoietic stem cells (HSC) and progenitors present in human cord blood can express nerve growth factor (NGF)-specific receptors, TrkA and p75. Our results showed a marked expression of TrkA and NGF in cord blood CD34(+) cells. A gradient of TrkA and NGF expression exists and is highest in cord blood CD34(+) cells, reduced in cord blood mononuclear cells (MNC) and minimal in mononuclear cells isolated from adult peripheral blood. Our findings suggest that NGF may play a role in the differentiation of hematopoietic progenitors and indicate a different requirement for NGF by immune cells, depending on their state of maturity.


Subject(s)
Antigens, CD34/immunology , Cell Differentiation/immunology , Fetal Blood/cytology , Hematopoietic Stem Cells/metabolism , Nerve Growth Factor/metabolism , Receptor, trkA/metabolism , Adult , Fetal Blood/immunology , Flow Cytometry , Fluorescent Antibody Technique , Hematopoietic Stem Cells/immunology , Humans , Infant, Newborn , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/metabolism , Middle Aged , Nerve Growth Factor/genetics , RNA, Messenger/metabolism , Receptor, Nerve Growth Factor , Receptor, trkA/genetics , Receptors, Nerve Growth Factor/genetics , Receptors, Nerve Growth Factor/metabolism
17.
J Biol Chem ; 278(4): 2136-40, 2003 Jan 24.
Article in English | MEDLINE | ID: mdl-12435754

ABSTRACT

Telomeres protect the ends of linear chromosomes from abnormal recombination events and buffer them against terminal DNA loss. Models of telomere replication predict that two daughter molecules have one end that is blunt, the product of leading-strand synthesis, and one end with a short G-rich 3'-overhang. However, experimental data from proliferating cells are not completely consistent with this model. For example, telomeres of human chromosomes have long G-rich 3'-overhangs, and the persistence of blunt ends is uncertain. Here we show that the product of leading-strand synthesis is not always blunt but can contain a long C-rich 5'-tail, the incompletely replicated template of the leading strand. We examined the presence of G-rich and C-rich single-strand DNA in fibroblasts and HeLa cells. Although there were no significant changes in the length distribution of the 3'-overhang, the 5'-overhangs were mostly present in S phase. Similar results were obtained using telomerase-negative fibroblasts. The amount and the length distribution of the 5' C-rich tails strongly correlate with the proliferative rate of the cell cultures. Our results suggest that, contrary to what has commonly been supposed, completion of leading-strand synthesis is inefficient and could well drive telomere shortening.


Subject(s)
Genetic Techniques , Telomere/physiology , Telomere/ultrastructure , Base Composition , DNA/analysis , DNA/ultrastructure , Fibroblasts/metabolism , G1 Phase , HeLa Cells , Humans , Models, Genetic , Nucleic Acid Conformation , Oligonucleotides/pharmacology , Recombination, Genetic , Repetitive Sequences, Nucleic Acid , S Phase
18.
Bull Math Biol ; 64(2): 355-84, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11926121

ABSTRACT

In the present paper we propose a method of analysis of the cell kinetic characteristics of in vivo experimental tumours, that uses DNA-BrdUrd flow cytometry data at various times after the bromodeoxyuridine (BrdUrd) injection and mathematical modelling. The model of the cell population takes into account the cell-cell heterogeneity of the progression rate across cell cycle phases within the tumour, and assumes a strict correlation between the durations of S and G2M phases. The model also allows for a nonconstant DNA synthesis rate across S phase. In addition, the measurement process is modelled, considering the possibility of nonimpulsive labelling and providing a representation of the time course of the bivariate DNA-BrdUrd fluorescence distribution. Sequential DNA-BrdUrd distributions were obtained in vivo from a human ovarian carcinoma transplanted in mice and, for comparison, in vitro from a cell line of the same origin. From these data, that included the fractional density and the mean BrdUrd-fluorescence of BrdUrd-positive cells as a function of the DNA-fluorescence, kinetic parameters such as the potential doubling time (Tpot) and the mean and variance of the transit times in S and G2M phases, were estimated. This study revealed the presence of a substantial heterogeneity in S and G2M phases within the in vivo cell population and of a lower heterogeneity in the in vitro population. Moreover, our analysis suggests a nonnegligible effect of the BrdUrd pharmacokinetics in the in vivo cell labelling.


Subject(s)
Carcinoma/pathology , Cell Cycle/physiology , Models, Biological , Ovarian Neoplasms/pathology , Animals , Bromodeoxyuridine/metabolism , Bromodeoxyuridine/pharmacokinetics , Carcinoma/metabolism , Cell Division/physiology , DNA, Neoplasm/metabolism , Female , Flow Cytometry , Humans , Kinetics , Mice , Mice, Nude , Ovarian Neoplasms/metabolism , Tumor Cells, Cultured
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