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1.
Sci Rep ; 12(1): 3775, 2022 03 08.
Article in English | MEDLINE | ID: mdl-35260588

ABSTRACT

Loop-mediated isothermal amplification is known for its high sensitivity, specificity and tolerance to inhibiting-substances. In this work, we developed a device for performing real-time colorimetric LAMP combining the accuracy of lab-based quantitative analysis with the simplicity of point-of-care testing. The device innovation lies on the use of a plastic tube anchored vertically on a hot surface while the side walls are exposed to a mini camera able to take snapshots of the colour change in real time during LAMP amplification. Competitive features are the rapid analysis (< 30 min), quantification over 9 log-units, crude sample-compatibility (saliva, tissue, swabs), low detection limit (< 5 copies/reaction), smartphone-operation, fast prototyping (3D-printing) and ability to select the dye of interest (Phenol red, HNB). The device's clinical utility is demonstrated in cancer mutations-analysis during the detection of 0.01% of BRAF-V600E-to-wild-type molecules from tissue samples and COVID-19 testing with 97% (Ct < 36.8) and 98% (Ct < 30) sensitivity when using extracted RNA and nasopharyngeal-swabs, respectively. The device high technology-readiness-level makes it a suitable platform for performing any colorimetric LAMP assay; moreover, its simple and inexpensive fabrication holds promise for fast deployment and application in global diagnostics.


Subject(s)
COVID-19 Nucleic Acid Testing/methods , COVID-19/diagnosis , COVID-19/virology , COVID-19 Nucleic Acid Testing/instrumentation , Colorimetry , Humans , Limit of Detection , Molecular Diagnostic Techniques , Nasopharynx/virology , Neoplasms/diagnosis , Neoplasms/genetics , Neoplasms/pathology , Nucleic Acid Amplification Techniques , Point-of-Care Testing , Proto-Oncogene Proteins B-raf/genetics , RNA, Viral/analysis , RNA, Viral/metabolism , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Sensitivity and Specificity , Smartphone
2.
Hum Exp Toxicol ; 33(12): 1241-52, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24818614

ABSTRACT

Lethal cardiac complications leading to death and various arrhythmias have been reported after organophosphate and/or carbamate poisonings. The present study focuses on the long-term effects of repeated low-level exposure to diazinon, propoxur, and chlorpyrifos (CPF) on cardiac function in rabbits. The yearly based experimental scheme of exposure consisted of two oral administration periods, lasting 3 months and 1 month each, interrupted by an 8-month washout period (total duration 12 months). At the end of the experimental scheme, the rabbits underwent an echocardiographic evaluation under sedation, after which they were killed and the tissue and serum samples were collected. A mild localized cardiotoxic effect was established by echocardiography for the three pesticides tested. Severe histological alterations were identified, especially in the diazinon-treated animals in agreement with increased persistence of this pesticide established in the cardiac tissue. In addition, all pesticides tested increased the oxidative stress and oxidative modifications in the genomic DNA content of the cardiac tissues, each one following a distinct mechanism.


Subject(s)
Cardiotoxicity/etiology , Chlorpyrifos/toxicity , Diazinon/toxicity , Insecticides/toxicity , Propoxur/toxicity , Animals , Chlorpyrifos/pharmacokinetics , Diazinon/pharmacokinetics , Echocardiography/drug effects , Female , Insecticides/pharmacokinetics , Monocytes/drug effects , Monocytes/enzymology , Myocardium/metabolism , Myocardium/pathology , Oxidative Stress/drug effects , Propoxur/pharmacokinetics , Rabbits , Telomerase/metabolism
3.
Cell Prolif ; 43(1): 9-18, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19845689

ABSTRACT

OBJECTIVES: Heparin acts as an extracellular stimulus capable of activating major cell signalling pathways. Thus, we examined the putative mechanisms utilized by heparin to stimulate HT29, SW1116 and HCT116 colon cancer cell growth. MATERIALS AND METHODS: Possible participation of the mitogen-activated protein kinase (MAPK) cascade on heparin-induced HT29, SW1116 and HCT116 colon cancer cell growth was evaluated using specific MAPK cascade inhibitors, Western blot analysis, real-time quantitative PCR and FACS apoptosis analysis. RESULTS: Treatment with a highly specific p38 kinase inhibitor, SB203580, significantly (50-70%) inhibited heparin-induced colon cancer cell growth, demonstrating that p38 MAPK signalling is involved in their heparin-induced proliferative response. This was shown to be correlated with increased (up to 3-fold) phosphorylation of 181/182 threonine/tyrosine residues on p38 MAP kinase. Furthermore, heparin inhibited cyclin-dependent kinase inhibitor p21(WAF1/CIP1) and p53 tumour suppressor gene and protein expression up to 2-fold or 1.8-fold, respectively, and stimulated cyclin D1 expression up to 1.8-fold, in these cell lines through a p38-mediated mechanism. On the other hand, treatment with heparin did not appear to affect HT29, SW1116 and HCT116 cell levels of apoptosis. CONCLUSIONS: This study demonstrates that an extracellular glycosaminoglycan, heparin, finely modulates expression of genes crucial to cell cycle regulation through specific activation of p38 MAP kinase to stimulate colon cancer cell growth.


Subject(s)
Colonic Neoplasms/enzymology , Heparin/pharmacology , MAP Kinase Signaling System , p38 Mitogen-Activated Protein Kinases/metabolism , Apoptosis , Cell Line, Tumor , Cyclin D1 , Cyclin-Dependent Kinase Inhibitor p21/genetics , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Flow Cytometry , HCT116 Cells , Humans , Imidazoles/pharmacology , Phosphorylation , Protein Kinase Inhibitors/pharmacology , Pyridines/pharmacology , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , p38 Mitogen-Activated Protein Kinases/genetics
4.
Toxicol Lett ; 186(1): 66-72, 2009 Apr 10.
Article in English | MEDLINE | ID: mdl-19022366

ABSTRACT

Allelic variants of CYP1A1 and PON1 have been extensively studied as susceptibility factors in toxic response, although little is known about the role of these variants as risk factors for the plethora of diseases appearing in the human population. In this study we investigated the hypothesis of correlation of CYP1A1 and PON1 enzymes with the incidence of various medical examination findings in a Greek rural population professionally exposed to a variety of pesticides. The medical history of 492 individuals, randomly selected for the total population of 42,000, was acquired by interviews and their genotype determined for the CYP1A1*2A, PON1 M/L and PON1 Q/R polymorphisms. The assessment of exposure to pesticides of the population was verified by analytical methods. Analysis of the genetic data revealed that the allele frequencies of PON1 R, M and CYP1A1*2A alleles were 0.243, 0.39 and 0.107 respectively. The CYP1A1*2A polymorphism was found to have significant association with chronic obstructive pneumonopathy (p=0.045), peripheral circulatory problems (trend p=0.042), arteritis (p=0.022), allergies (trend p=0.046), hemorrhoids (trend p=0.026), allergic dermatitis (p=0.0016) and miscarriages (p=0.012). The PON1 Q/R polymorphism was found to have significant association with hypertension (p=0.046) and chronic constipation (p=0.028) whereas, the L/M polymorphism, with diabetes (p=0.036), arteritis (trend p=0.022) and hemorrhoids (trend p=0.027). Our results demonstrated an association between the CYP1A1/PON1 polymorphisms and several medical examination findings, thus indicating the possible involvement of the human detoxification system to health effects in a rural population exposed professionally to pesticides.


Subject(s)
Aryldialkylphosphatase/genetics , Cytochrome P-450 CYP1A1/genetics , Environmental Exposure , Environmental Illness/etiology , Pesticides/adverse effects , Polymorphism, Genetic , Rural Health , Adolescent , Adult , Aged , Aged, 80 and over , Cross-Sectional Studies , Environmental Illness/epidemiology , Female , Genetic Predisposition to Disease , Greece/epidemiology , Hair/chemistry , Humans , Hydrocarbons, Chlorinated/adverse effects , Hydrocarbons, Chlorinated/analysis , Inactivation, Metabolic/genetics , Male , Middle Aged , Organophosphorus Compounds/adverse effects , Organophosphorus Compounds/analysis , Pesticides/analysis , Surveys and Questionnaires , Young Adult
5.
Biochim Biophys Acta ; 1780(2): 194-202, 2008 Feb.
Article in English | MEDLINE | ID: mdl-17980161

ABSTRACT

Versican, a large chondroitin sulphate proteoglycan and hyaluronan (HA), a non-sulphated glycosaminoglycan are major constituents of the pericellular matrix. In many neoplastic tissues, changes in the expression of versican and HA affect tumour progression. Here, we analyse the synthesis of versican and hyaluronan by fibrosarcoma cells, and document how the latter is affected by PDGF-BB, bFGF and TGFB2, growth factors endogenously produced by these cells. Fibrosarcoma cell lines B6FS and HT1080 were utilised and compared with normal lung fibroblasts (DLF). The major versican isoforms expressed by DLF and B6FS cells were V0 and V1. Treatment of B6FS cells with TGFB2 showed a significant increase of V0 and V1 mRNAs. Versican expression in HT1080 cells was not significantly affected by any of the growth factors. In addition, TGFB2 treatment increased versican protein in DLF cells. HA, showed approximately a 2-fold and a 9-fold higher production in DLF cells compared to B6FS and HT1080 cells, respectively. In HT1080 cells, HA biosynthesis was significantly increased by bFGF, whereas, in B6FS cells it was increased by TGFB2 and PDGF-BB. Furthermore, analysis of HA synthases (HAS) expression indicated that HT1080 expressed similar levels of all three HAS isoforms in the following order: HAS2> HAS3> HAS1. bFGF shifted that balance by increasing the abundance of HAS1. The major HAS isoform expressed by B6FS cells was HAS2. PDGF-BB and TGFB2 showed the most prominent effects by increasing both HAS2 and HAS1 isoforms. In conclusion, these growth factors modulated, through upregulation of specific HAS isoforms, HA synthesis, secretion and net deposition to the pericellular matrix.


Subject(s)
Fibroblast Growth Factor 2/metabolism , Fibrosarcoma/metabolism , Hyaluronic Acid/biosynthesis , Platelet-Derived Growth Factor/metabolism , Transforming Growth Factor beta2/metabolism , Versicans/biosynthesis , Becaplermin , Cell Line, Tumor , Fibroblast Growth Factor 2/pharmacology , Glucuronosyltransferase/analysis , Glucuronosyltransferase/metabolism , Humans , Hyaluronan Synthases , Platelet-Derived Growth Factor/pharmacology , Protein Isoforms/metabolism , Proto-Oncogene Proteins c-sis , Transforming Growth Factor beta2/pharmacology
6.
J Cell Biochem ; 103(6): 1866-76, 2008 Apr 15.
Article in English | MEDLINE | ID: mdl-17960571

ABSTRACT

Platelet-derived growth factor (PDGF) is a major polypeptide mitogen for cells of mesenchymal origin such as fibroblasts. Chondroitin sulfate chains (CS), which are abundant in the extracellular matrix have been shown to physically interact with PDGF-BB modulating its biological function. The aim of the present study was to examine the involvement of CS on PDGF-BB induced proliferative responses and receptor activation in human lung fibroblasts. The addition of exogenous free CS chains caused a significant downregulation of the PDGF-BB mediated mitogenic and chemotactic responses. Similar results were obtained by the increase of endogenous CS biosynthesis after beta-D-xyloside treatment. Furthermore, removal of the membrane-bound CS chains by selective enzymatic treatment significantly increased the proliferative capacity of human fibroblasts. Analysis of PDGF-R phosphorylation in the presence of CS or beta-D-xyloside, revealed a reduction of PDGF-Rbeta phosphorylation in the tyrosine residue 1021. These results demonstrate, for the first time, that CS either soluble or surface bound downregulates the mitogenic responses of PDGF-BB in normal human lung fibroblasts through the reduction of PDGF-Rbeta phosphorylation.


Subject(s)
Chondroitin Sulfates/pharmacology , Fibroblasts/physiology , Platelet-Derived Growth Factor/pharmacology , Receptor, Platelet-Derived Growth Factor beta/metabolism , Becaplermin , Cell Proliferation/drug effects , Cells, Cultured , Chemotaxis , Chondroitin Sulfates/physiology , Fibroblasts/drug effects , Glycosides/pharmacology , Humans , Lung/cytology , Phosphorylation , Platelet-Derived Growth Factor/physiology , Proto-Oncogene Proteins c-sis , Signal Transduction
7.
Int J Biochem Cell Biol ; 38(12): 2141-50, 2006.
Article in English | MEDLINE | ID: mdl-16945567

ABSTRACT

Platelet derived growth factor is involved in the autocrine growth stimulation of malignant cells, the stimulation of angiogenesis and the recruitment and regulation of tumor fibroblasts. PDGF has been shown to physically interact with glycosaminoglycans which are abundant in the fibrosarcoma cell microenvironment. Aim of the present study was to examine the effects of glycosaminoglycans on the mitogenic function of platelet derived growth factor in two human fibrosarcoma cell lines (B6FS, HT1080). For this purpose exogenously added glycosaminoglycans, regulators of endogenous glycosaminoglycan synthesis (sodium chlorate as selective inhibitor and beta-D-xyloside as a stimulator) and specific glycosidases to cleave cell-associated glycosaminoglycans, were utilized. Platelet derived growth factor demonstrated a growth stimulating effect on B6FS, whereas no effect was evident on HT1080 fibrosarcoma cells. Beta-D-xyloside had no effect on the basal level or the platelet derived growth factor-induced cell proliferation, whereas sodium chlorate severely reduced the basal level of proliferation in both cell lines. Significant co-stimulatory effects of chondroitin sulfate A in combination with platelet derived growth factor BB on the growth of HT1080 and B6FS cells were found. The co-stimulatory effect of chondroitin sulfate A was not due to transcriptional up regulation of platelet derived growth factor receptors genes, but rather to more efficient signalling of tyrosine kinase receptors. In conclusion, this study shows that chondroitin sulfate A can enhance the mitogenic activity of platelet-derived growth factor in fibrosarcoma cells utilizing a pathway which involves tyrosine kinases. This result introduces a new modulating role for chondroitin sulfate in signalling pathways critical for cancer growth.


Subject(s)
Chondroitin Sulfates/pharmacology , Fibrosarcoma/metabolism , Platelet-Derived Growth Factor/pharmacology , Signal Transduction/drug effects , Becaplermin , Cell Proliferation/drug effects , Chlorates/pharmacology , Fibrosarcoma/pathology , Gene Expression Regulation/drug effects , Genistein/pharmacology , Glycosides/pharmacology , Humans , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins c-sis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Receptor, Platelet-Derived Growth Factor alpha/genetics , Receptor, Platelet-Derived Growth Factor beta/genetics , Transcription, Genetic/drug effects
8.
IUBMB Life ; 58(1): 47-53, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16540432

ABSTRACT

Versican, a large sized chondroitin-sulphate proteoglycan (PG), and its binding partner, hyaluronan (HA), are extracellular matrix (ECM) components that play an essential role in transformed cell behavior. Expression of certain versican isoforms has been implicated in cell migration and proliferation of cancer cells and, on the other hand, disruption of HA synthesis by inhibiting hyaluronan synthase-2 (HAS2) expression in osteosarcoma cells by suppressing cell proliferation, invasiveness and motility. Considering that growth factors, such as TGF-beta, bFGF and PDGF-BB, are important regulators for the expression of the ECM macromolecules, in this study we examined the effect of these growth factors on the expression of the various versican isoforms, HA synthases as well as HA synthesis by MG-63 osteosarcoma cells and normal human osteoblastic periodontal ligament cells (hPDL). Real-time PCR and metabolic labelling followed by fine HPLC analysis coupled to radiochemical detection were the methods utilized. It was found that, contrary to normal hPDL cells, osteosarcoma MG-63 cells do not constitutively express the versican isoforms V0 and V1. Exogenous addition of TGF-beta2 stimulated the versican transcript levels mainly by forcing osteosarcoma cells to express V1 and V0 isoforms. PDGF-BB and bFGF had only minor effects in these cells. In hPDL cells a strong stimulation of the V3 transcript by all growth factors was observed. TGF-beta2 was also the major stimulator of HAS2 isoform expression as well as hyaluronan synthesis in osteosarcoma cells, while PDGF-BB exerted dominant influence on HAS2 isoform expression and hyaluronan biosynthesis by osteoblasts. The obtained results show for the first time that TGF-beta2 triggers the malignant phenotype pattern of versican and hyaluronan expression in human osteosarcoma cells and indicate that this growth factor may account for the metastatic potential of these cells.


Subject(s)
Bone Neoplasms/metabolism , Chondroitin Sulfate Proteoglycans/genetics , Glucuronosyltransferase/genetics , Hyaluronic Acid/biosynthesis , Lectins, C-Type/genetics , Osteosarcoma/metabolism , Transforming Growth Factor beta/pharmacology , Becaplermin , Bone Neoplasms/genetics , Cell Line, Tumor , Fibroblast Growth Factors/pharmacology , Gene Expression/drug effects , Humans , Hyaluronan Synthases , Osteosarcoma/genetics , Platelet-Derived Growth Factor/pharmacology , Protein Isoforms/genetics , Proto-Oncogene Proteins c-sis , Transforming Growth Factor beta2 , Versicans
9.
Pediatr Blood Cancer ; 47(1): 14-21, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16526056

ABSTRACT

BACKGROUND: Cyclin-dependent kinases (CDKs) and cyclins, their regulatory subunits, govern cell-cycle progression in eukaryotic cells. Kip1/p27 is the main cyclin-dependent kinase inhibitor, which arrests cell division inhibiting G1-S transition. Kip1/p27 seems to play a critical role in the pathogenesis of several human malignancies and its lower expression has been shown to correlate with a poor prognosis in adult solid tumors. METHODS: Bone marrow blasts from 49 children with leukemia, 37 acute lymphoblastic leukemia (ALL), and 12 acute myeloid leukemia (AML) were studied. Exon 3 of Kip1/p27 was amplified using the polymerase chain reaction technique (PCR). Single strand conformational polymorphism and heterodouplex analysis were performed to detect DNA sequence with altered conformations and were subsequently sequenced to document mutations. RESULTS: Mutations in Kip1/p27 gene were detected in 2 out of 3 T-ALL, 6 out of 12 AML patients, and only 1 out of 34 B lineage ALL cases. Although the patient groups are small, a highly significant relation of the mutation status with the type of leukemia (P = 0.0037) and the risk group according to treatment protocols (P = 0.00021) was estimated. A statistically significant difference in the white blood count was observed (P = 0.019) between the mutated and non-mutated patient groups although no statistically significant association of the mutation status with the hemoglobin and platelets values, karyotype, age, sex, disease progression, and outcome was determined. CONCLUSIONS: Based upon these results, the Kip1/p27 mutations should be considered for further prospective testing as an additional parameter for risk stratification and treatment of childhood leukemia.


Subject(s)
Biomarkers, Tumor/genetics , Cyclin-Dependent Kinase Inhibitor p27/genetics , Leukemia, Myeloid/genetics , Mutation , Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics , Acute Disease , Adolescent , Bone Marrow/pathology , Cell Cycle/drug effects , Child , Child, Preschool , DNA Mutational Analysis , Female , Humans , Infant , Male , Prognosis
10.
Anticancer Res ; 25(4): 2851-6, 2005.
Article in English | MEDLINE | ID: mdl-16080537

ABSTRACT

Osteoblastic cells produce a complex extracellular matrix (ECM) composed of a mixture of proteoglycans (PGs), collagens and non-collagenous proteins. The interaction of proteoglycans with matrix effector macromolecules via either their glycosaminoglycan (GAG) chains or their protein core is critical in regulating a variety of cellular events. Alterations in the structural composition of the GAG/PG component of the ECM may have important consequences on cell proliferation and/or differentiation. Human osteoblasts and two osteosarcoma cell lines, able to produce galactosaminoglycan (GalAGs) and heparan sulphate (HS)-containing proteoglycans, were treated with their main GAG chain types, and the effects on cell growth were examined. Chondroitin sulphate (CSA) and dermatan sulphate (DS) inhibited cell proliferation of all osteoblastic cell lines at high concentration (100 microg/ml). DS showed the stronger inhibitory effect, probably due to the presence of flexible IdoA residues that provide a greater variety in conformation to these macromolecules. Heparin strongly inhibited the proliferation rates of both normal osteoblasts and transformed osteoblastic cells at concentrations > or = 1 microg/ml. The presence of large amounts of IdoA-derived trisulphated disaccharides, responsible for the overall negative charge of heparin, should be considered as a critical factor for the inhibition of cell proliferation. The obtained results suggest that matrix GAGs are factors which affect cell growth of both malignant and normal cells of the osteoblastic lineage in a concentration-dependent manner. This effect is closely related to the fine chemical structure of GAGs, i.e. the presence of L-iduronic acid and the degree of sulphation.


Subject(s)
Bone Neoplasms/drug therapy , Glycosaminoglycans/pharmacology , Osteoblasts/drug effects , Osteosarcoma/drug therapy , Bone Neoplasms/chemistry , Bone Neoplasms/metabolism , Bone Neoplasms/pathology , Cell Growth Processes/drug effects , Cell Line, Transformed , Cell Line, Tumor , Chondroitin Sulfates/pharmacology , Dermatan Sulfate/pharmacology , Glycosaminoglycans/isolation & purification , Glycosaminoglycans/metabolism , Heparin/pharmacology , Humans , Osteoblasts/chemistry , Osteoblasts/cytology , Osteoblasts/metabolism , Osteosarcoma/chemistry , Osteosarcoma/metabolism , Osteosarcoma/pathology
11.
Int J Biol Markers ; 20(1): 18-27, 2005.
Article in English | MEDLINE | ID: mdl-15832769

ABSTRACT

Deregulation of the apoptotic machinery plays a major role in cell death, cellular transformation and cancer. p53, Bcl-2, Bcl-XL, Bax and Mdm2 mRNA expression patterns were evaluated in tissue samples with cervical intraepithelial neoplasia (CIN) and cervical cancer compared to those of normal cervical tissues, and correlated with the underlying cervical lesions. Transcript levels of the above genes were assessed by RT-PCR analysis in a total of 44 cervical specimens. p53, Bcl-2, Bax and Mdm2 transcript levels were significantly different in the normal, CIN and cancer specimen groups (p=0.003, p=0.009, p=0.040 and p=0.001, respectively). Specifically, p53, Bax and Bcl-2 exhibited substantially lower transcript levels in CIN lesions compared to controls, whereas Bax mRNA levels showed a significant decrease in cancer compared to normal specimens. Mdm2 mRNA expression was considerably lower in cancer than in CIN lesions or normal cervix. High-grade squamous intraepithelial lesions exhibited lower p53 and Bcl-2 mRNA levels than controls (p=0.002, p=0.016). Coexpression analysis revealed more correlations between the above apoptosis-related molecules in normal tissues compared to CIN or cancer specimens. p53 showed significant coexpression with Bax, Bcl-2 and Mdm2 (p=0.040, p=0.013 and p=0.015, respectively) in normal cervical specimens. Bax and Bcl-XL mRNA expression was negatively correlated. Mdm2 transcriptional levels correlated significantly with those of Bax, Bcl-XL and Bcl-2. Our findings show that p53, Bax, Bcl-2 and Mdm2 mRNA expression levels correlate with the malignant transformation of the uterine cervix. mRNA coexpression patterns of the members of the pro- and anti-apoptotic family examined in cervical carcinogenesis were found to be disrupted in CIN and cancer, as already demonstrated at the protein level.


Subject(s)
Cell Transformation, Neoplastic/genetics , Nuclear Proteins/genetics , Proto-Oncogene Proteins c-bcl-2/genetics , Proto-Oncogene Proteins/genetics , Tumor Suppressor Protein p53/genetics , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Apoptosis/genetics , DNA, Viral/analysis , DNA, Viral/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Middle Aged , Nuclear Proteins/deficiency , Papillomaviridae/genetics , Proto-Oncogene Proteins/deficiency , Proto-Oncogene Proteins c-bcl-2/deficiency , Proto-Oncogene Proteins c-mdm2 , RNA, Messenger/genetics , RNA, Messenger/metabolism , Transcription, Genetic/genetics , Tumor Suppressor Protein p53/deficiency , bcl-2-Associated X Protein
12.
Int J Biol Markers ; 20(4): 257-63, 2005.
Article in English | MEDLINE | ID: mdl-16398408

ABSTRACT

OBJECTIVE: Human papillomavirus (HPV) has been identified as the principal etiologic agent for cervical cancer and its precursors. Different HPV types have been associated with different oncogenic potential. The purpose of this study was to evaluate the relationship between specific HPV type infection and expression pattern of the ras family oncogenes in different grades of HPV-associated human cervical neoplasia. METHODS: HPV typing was performed using polymerase chain reaction (PCR) in 31 HPV-positive human cervical specimens from patients with squamous intraepithelial lesions (SIL) or squamous cervical carcinoma (SCC). The mRNA expression levels of H-, K- and N-ras oncogenes were examined using the reverse transcriptase polymerase chain reaction (RT-PCR) technique. Statistical analyses were performed using SPSS software. RESULTS: Among patients with SCC, H-, K- and N-ras expression levels were higher in HPV 16/18-associated cases compared to HPV 16/18-unassociated samples (p=0.003, p=0.004 and p=0.0001, respectively). The expression levels for H-, K- and N-ras were significantly higher in SCC patients with multiple HPV infection compared with SCC patients with single HPV infection (p=0.009, p=0.01 and p=0.021, respectively). Among patients with SIL, no statistically significant relationship was found between ras expression and HPV status. CONCLUSION: Our findings indicate the possible role of ras signaling interaction with "high-risk" HPV 16/18 and multiple HPV infection in cervical cancer development.


Subject(s)
Carcinoma, Squamous Cell/genetics , Gene Expression Regulation, Neoplastic/genetics , Genes, ras/genetics , Papillomaviridae/classification , Papillomavirus Infections/genetics , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/virology , Carcinoma, Squamous Cell/virology , Female , Humans , Middle Aged , Papillomavirus Infections/complications , Papillomavirus Infections/virology , RNA, Messenger/genetics , RNA, Messenger/metabolism
13.
Int J Biochem Cell Biol ; 37(2): 409-15, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15474985

ABSTRACT

Loss of genomic rDNA has been associated with cellular and organismal ageing. The rDNA locus in humans comprises multiple copies of the 5.8S, 28S and 18S genes. Aim of the present study was to test the effect of aging on the copy number of the three rDNA genes individually in post-mitotic human tissue. We utilized real time polymerase chain reaction relative quantification to measure the copy number of 5.8S, 28S and 18S rDNA genes individually. We obtained adipose tissue from 120 male individuals aged from 9 to 94 years. The available data of each subject corresponding to the time of tissue sampling included: age, height, weight and calculated body mass index. Each rDNA gene was directly tested with Pearson correlation against age and body mass index. We found a significant negative correlation of the gene copy of 5.8S (P < 0.001) and 28S (P < 0.003) with age. Interestingly 18S gene copy displayed a different pattern with no statistically significant correlation with age. Conversely, we observed a significant negative correlation of the 18S gene copy with body mass index (P = 0.004) and a marginally non-significant negative correlation of the 5.8S (P = 0.097) gene copy with body mass index. In summary our results indicate that the rDNA recombination events in humans can be differentially targeted and regulated in response to ageing and/or fat accumulation. The proposed model generates possible implications regarding the effects of each rDNA gene loss in cell function as well as the mechanism of recombination targeting.


Subject(s)
Adipose Tissue/physiology , Aging/genetics , DNA, Ribosomal/genetics , Gene Deletion , Gene Dosage , Recombination, Genetic , Adolescent , Adult , Aged , Aged, 80 and over , Child , Humans , Male , Middle Aged , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 5S/genetics
14.
Eye (Lond) ; 19(2): 210-4, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15232598

ABSTRACT

AIMS: Ophthalmic pterygium is a potentially vision-threatening lesion of unknown etiology, related to an exposure to solar light. Mutations to the ras genes are frequently observed in lesions related to an exposure to solar light. The present study aims at screening pterygia for mutations at codons 12 and 13 of the ras genes. METHODS: In all, 50 pterygia were examined, together with respective blood samples and specimens of normal conjunctiva. A PCR reaction was performed to amplify sequences containing codons 12 and 13 of Ki-ras, H-ras, and N-ras. An RFLP analysis was then performed to detect point mutations at codon 12. The mutational status at codons 12 and 13 was further explored with sequencing of PCR products. RESULTS: RFLP analysis revealed Ki-ras mutations at codon 12 in five (10%) of pterygia, whereas H-ras or N-ras mutations were not observed. Sequencing confirmed Ki-ras mutations at codon 12 and revealed absence of mutations at codon 13. The presence of Ki-ras mutations was significantly correlated with postoperative recurrence (P=0.02) and young age (P=0.04). Mutations were not observed in specimens of blood or normal conjunctiva for any of the genes examined. CONCLUSIONS: The absence of N-ras mutations is in agreement with previous reports concerning mucosal lesions. The detection of Ki-ras mutations and the association with postoperative recurrence implies a possible role of Ki-ras in the clinical profile of pterygium. The mechanism of Ki-ras mutations is unclear and could be independent of the action of UV light.


Subject(s)
Genes, ras/genetics , Genetic Predisposition to Disease , Point Mutation , Pterygium/genetics , Adult , Aged , Aged, 80 and over , Base Sequence , Cell Cycle Proteins/genetics , Codon/genetics , Cyclin-Dependent Kinase Inhibitor p21 , DNA Mutational Analysis , Female , Humans , Male , Middle Aged , Polymerase Chain Reaction/methods , Polymorphism, Restriction Fragment Length , Pterygium/surgery , Recurrence
16.
Eur J Hum Genet ; 12(7): 535-41, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15083167

ABSTRACT

Schizophrenia is a severe and common psychiatric disorder afflicting 1% of the world population. A role of many neurotransmitter receptors in schizophrenia was suggested by an association with several polymorphisms located in their coding regions. In this study we examined the contribution of the T-102C and A-206G transitions in the 5-HTR2a and DRD3 receptor genes respectively to genetic susceptibility and phenotypic expression of schizophrenia disorder within the Greek population. We determined by PCR and RFLP analysis the genotype for the above polymorphisms in 114 schizophrenic hospitalized individuals and 192 control samples. In contrast to previous reports from large European multicentre studies, which indicate significant correlation between schizophrenia and C-102 allele of the T-102C polymorphism, in this study we observed a statistically significant overall association between the disorder and allele T-102 (P<0.0001, odds ratio (OR)=2.11, 95% CI=1.48-3.02). We also found a highly significant excess of the T-102/C-102 and C-102/C-102 genotypes in the normal group (P<0.001). Comparison of the patients with the controls for the DRD3 polymorphism (A-206G transition) showed marginally nonsignificant differences in the genotypic (P=0.054) and no significance in the allelic (P=0.163) frequencies. However, the A-206/A-206 genotype seems to positively contribute to the disorder appearance, when compared to A-206/G-206 as genotype base line risk (P=0.016, OR=1.88, 95% CI=1.09-3.26). In conclusion, from genetic association analysis of this schizophrenic population, a significant association is clearly determined between the HTR2 genetic polymorphism and the presence of schizophrenic disorder, manifested as increased risk of schizophrenia for carriers of the T-102 allele.


Subject(s)
Genetic Predisposition to Disease/genetics , Polymorphism, Restriction Fragment Length , Receptor, Serotonin, 5-HT2A/genetics , Receptors, Dopamine D2/genetics , Schizophrenia/genetics , Adult , Case-Control Studies , Female , Gene Frequency/genetics , Genotype , Humans , Male , Middle Aged , Receptors, Dopamine D3
17.
Scand J Immunol ; 59(2): 231-4, 2004 Feb.
Article in English | MEDLINE | ID: mdl-14871302

ABSTRACT

The main cell population affected by the human immunodeficiency virus-1 (HIV-1) infection belongs to the CD4+ T-lymphocyte family. Recent convincing evidence indicates that the majority of the cells that die due to HIV-1 are not actually infected by the virus. Instead, these cells are being led to programmed cell death after the activation of apoptotic mechanisms by the virus or its components. We propose here from accumulated evidence that the virus appears to deregulate the physiological function of these cells during the process of antigen presentation. Ionic interactions between the variable V3 domain of the HIV-1 coat glycoprotein gp120 and the amino terminal of the chemokine receptor CCR5 play a prominent role in this process, and we speculate that nature has evolved simple electrostatic interaction mechanisms which, coupled to specific recognition systems on the cell surface, can initiate and modulate certain cellular events without the need for specific molecular structures. HIV-1 utilizes such a mechanism to ensure activation of the target host cell.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , HIV Envelope Protein gp120/immunology , HIV Infections/virology , HIV-1/pathogenicity , Receptors, CCR5/immunology , Amino Acid Sequence , Apoptosis/immunology , HIV Envelope Protein gp120/chemistry , HIV Infections/immunology , Humans , Molecular Sequence Data , Receptors, CCR5/chemistry , Static Electricity
18.
Cancer Lett ; 198(1): 77-81, 2003 Jul 30.
Article in English | MEDLINE | ID: mdl-12893433

ABSTRACT

We examined the possible involvement of human herpes viruses in sporadic non-melanoma skin cancer of Greek patients. Polymerase chain reaction (PCR) based detection assays were utilized for the detection of viral cytomegalovirus (CMV), herpes simplex virus (HSV) and Epstein-Barr virus (EBV) genomes in 24 squamous cell carcinomas (SCC), five Bowen's disease, 72 basal cell carcinomas (BCC) specimens and eight premalignant lesions. Forty-two of 109 (38.5%) skin lesions were found positive for CMV DNA. The highest incidence was 6/8 (75%) observed in specimens with premalignant lesions. The incidence was 37.5% (27/72) in BCC, 33% (8/24) in SCC and 20% (1/5) in extragenital Bowen's disease. All samples were negative for HSV-1/2 and EBV DNA as assessed by our PCR based assay. The CMV infection showed no statistically significant correlation with the histological type, age, site of lesion or sex. Our results give a strong indication of the possible involvement of CMV in non-melanoma skin cancer development.


Subject(s)
Herpesviridae/isolation & purification , Skin Neoplasms/virology , Adult , Aged , Cytomegalovirus/isolation & purification , DNA, Viral/analysis , Female , Herpes Simplex , Herpesviridae/genetics , Herpesvirus 1, Human/isolation & purification , Herpesvirus 2, Human/isolation & purification , Humans , Middle Aged , Simplexvirus/isolation & purification
19.
Br J Dermatol ; 148(4): 638-48, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12752119

ABSTRACT

BACKGROUND: Nonmelanoma skin cancers [squamous cell carcinomas (SCC) and basal cell carcinomas (BCC)] are the most common neoplasias of the Caucasian population. OBJECTIVES: The purpose of our study was to determine the involvement of CDKN2A genes in the development of sporadic nonmelanoma skin cancer in Greek patients. PATIENTS AND METHODS: Allelic imbalance analysis was performed in 22 SCC and five Bowen's disease specimens. Mutational analysis was performed on exons 1alpha, 1beta and 2 of the CDKN2A locus in 22 SCC, five Bowen's disease and 39 BCC specimens. Exon 1alpha was additionally screened in 28 BCC specimens to complete the mutational analysis of a previous study. RESULTS: Overall, 52% (14 of 27) of the SCC and Bowen's disease specimens exhibited loss of heterozygosity (LOH) in at least one microsatellite marker, whereas, only two of 27 (7%) exhibited microsatellite instability. LOH in 9p appears to be equally involved in both BCC and SCC tumours. Exons 1alpha, 1beta and 2 of the CDKN2A locus were screened for mutations. A Val28Gly substitution in exon 1alpha and a CCC-->TTT (Ala57Val and Arg58Ter) substitution in exon 2, resulting in a change in the amino acid sequence, are reported for the first time in two SCCs, the latter being indicative of a combination of an ultraviolet (UV) radiation-induced mutation and a point mutation. A previously described polymorphism of CDKN2A, the gene for p16INK4a, Ala148Thr, was also detected in an allelic frequency of 3.72%. No mutation was found in any of the five Bowen's disease specimens, or in exon 1beta of CDKN2A, also the gene for p14ARF. CONCLUSIONS: Mutations and the high incidence of 9p LOH detected in our SCC samples imply that inactivation of CDKN2A genes, via allelic loss and/or mutation (probably UV-induced) may play a significant role in nonmelanoma skin cancer development, particularly in the more aggressive SCC type.


Subject(s)
Carcinoma, Squamous Cell/genetics , Genes, p16 , Mutation , Skin Neoplasms/genetics , Adult , Aged , Aged, 80 and over , Bowen's Disease/genetics , Carcinoma, Basal Cell/genetics , DNA Mutational Analysis , DNA, Neoplasm/genetics , Female , Humans , Loss of Heterozygosity , Male , Microsatellite Repeats , Middle Aged , Polymorphism, Single-Stranded Conformational
20.
J BUON ; 8(2): 127-32, 2003.
Article in English | MEDLINE | ID: mdl-17472238

ABSTRACT

PURPOSE: Recombinant human erythropoietin (rHuEPO) represents an attractive alternative to red blood cell (RBC) transfusions for the treatment of chemotherapy-induced anaemia. This prospective, controlled study evaluated the safety and efficacy of rHuEPO in reducing RBC transfusion requirements in patients receiving platinum-based chemotherapy. PATIENTS AND METHODS: Patients with histologically proven malignancies, haemoglobin (Hb) values <10.5 g/dl, and receiving platinum-based chemotherapy were randomised to either 150 IU/kg of rHuEPO subcutaneously (s.c.) x3/week (group A), or simple follow-up plus RBC transfusions upon indication (group B). All patients received 200mg of elementary iron (Fe) daily. RESULTS: A total of 47 patients were randomised to either group A (n=24) or the control group B (n=23). There was a statistically significant increase of Hb (p <0.0002) and haematocrit (Ht) (p <0.002) in group A patients compared to the control group B. The levels of Hb in group A patients increased significantly with each chemotherapy cycle number. There was a statistically significant (p <0.04) difference in the number of transfusions between the two groups, with only 37.5% of group A patients requiring a RBC transfusion at any time during the study, compared to all patients (100%) in group B. CONCLUSIONS: Administration of rHuEPO is an effective intervention for the management of chemotherapy-induced anaemia, significantly reducing RBC transfusion requirements in patients receiving platinum-based chemotherapy. Hb and Ht levels proved reliable indicators for response to rHuEPO treatment.

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