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G Botti

Publications and source records attributed to G Botti.

At least 37 records · Page 2Linked to original sources
PubMed2000

Lysyl oxidase activates the transcription activity of human collagene III promoter. Possible involvement of Ku antigen.

Lysyl oxidase is an extracellular enzyme that controls the maturation of collagen and elastin. Lysyl oxidase and collagen III often show similar expression patterns in fibrotic tissues. Therefore, we investigated the influence of lysyl oxidase overexpression on the promoter activity of human COL3A1 gene. Our results showed that when COS-7 cells overexpressed the mature form of lysyl oxidase, the activity of the human COL3A1 promoter was increased up to an average of 12 times when tested by luciferase reporter assay. The effect was specific, because other promoters were not affected. Moreover, lysyl oxidase effect was abolished by beta-aminopropionitrile, a specific inhibitor of its catalytic activity. Electrophoretic mobility shift assay showed a binding activity in the region from -101 to -77 that was significantly increased by lysyl oxidase overexpression. The binding was specifically competed by the cold probe, and the mutagenesis of this region abolished both the binding activity in gel retardation and lysyl oxidase stimulation of COL3A1 promoter in transfection experiments. We identified the binding activity as Ku antigen in its two components: Ku80 and Ku70. This study suggests a new coordinated mechanism by which lysyl oxidase might control the development of fibrosis.

Aminopropionitrile↗
PubMed2000

Coordinate up-regulation of Sp1 DNA-binding activity and urokinase receptor expression in breast carcinoma.

The regulatory mechanisms underlying the overexpression of urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in highly invasive breast carcinomas remain poorly understood. In this study, we have simultaneously determined the level of uPAR and the activity of the transcription factor Sp1 in 14 breast carcinomas and 5 benign lesions. We found that uPAR levels and Sp1-binding activity are coordinately elevated in malignant tumors (r, 0.94; P < 0.001). On the contrary, undetectable or only barely detectable levels of uPAR and Sp1 activity were found in benign breast lesions. Finally, the engagement of uPAR by catalytically inactive uPA in the MDA-MB-231 breast carcinoma cell line results in a rapid up-regulation of Sp1-binding activity followed by an increase of uPAR protein. These results, taken together, suggest the existence of a uPA-dependent positive regulatory loop that may progressively enhance malignant breast cell invasiveness.

Adult↗
PubMed2000

Changing patterns of breast cancer stage at diagnosis in southern italy: hospital data as indicators of progressive changes.

BACKGROUND: In southern Italy diagnostic delay in breast cancer patients has been demonstrated to be related to the level of education and residency in rural areas. In order to verify whether late breast cancer diagnosis was actually in decline as a result of improving socioeconomic conditions and ongoing prevention programs, we evaluated clinical data from the tumor registry of the National Cancer Institute, Naples. METHODS: Four thousand two hundred forty consecutive breast cancer patients admitted to our institution from 1986 to 1997 were grouped into four 3-year periods according to their admission date. Using multiple logistic regression, chi(2) for trend and beta-coefficient were calculated in each pT and pN categories in order to discover the trend for the 1986-1997 period. RESULTS: A progressive, statistically significant decrease in the number of patients with advanced cancer at the time of diagnosis was observed over the study period. In particular, chi(2) values for trend for each pT category, over the study period, were pT1 119.4 (P < 0.001) with positive chi-coefficient, pT2 13.4 (P = 0.003) with negative beta, and pT3-pT4 152.2 (P < 0.001) with the strongest negative beta. CONCLUSIONS: Changing patterns of breast cancer stage at diagnosis have been demonstrated in women living in Southern Italy. They are consistent with an increasing orientation toward prevention. Data from hospital tumor registries are a useful source of information on diagnostic delay.

Adult↗
PubMed2000

Weekly docetaxel plus gemcitabine or vinorelbine in refractory advanced breast cancer patients: a parallel dose-finding study. Southern Italy Cooperative Oncology Group (SICOG).

PURPOSE: The objective of this study was to determine the docetaxel MTD when combined with gemcitabine or vinorelbine in advanced breast cancer patients who had received previous anthracycline-based chemotherapy for advanced disease. PATIENTS AND METHODS: Advanced breast cancer patients aged between 18 and 70 with ECOG PS 0-2 who had not responded to, or had relapsed after, first-line anthracycline-based chemotherapy, were randomized to receive either gemcitabine 1000 mg/m2 or vinorelbine 25 mg/m2 in combination with escalating doses of docetaxel (starting from 30 mg/m2), all on days 1 and 8 every three weeks. Escalation was stopped if > 33% of patients treated at a given dose level showed DLT at the first cycle. RESULTS: A total of 34 patients with locally advanced (8) or metastatic disease (26) were treated, for a total of 94 cycles delivered. Nineteen patients received docetaxel in combination with gemcitabine and 15 with vinorelbine. All patients had been pretreated with anthracyclines, and 24 of 34 had also received weekly dose-dense paclitaxel. A docetaxel dose of 40/m2 proved to be safe when combined on days 1 and 8 with gemcitabine, while a dose of 35 mg/m2 was tolerated in combination with vinorelbine. Overall, nine episodes of DLT, all of them neutropenia, occurred at the first cycle. Considering all 94 cycles, grades 3 or 4 neutropenia and thrombocytopenia occurred in 15 (44%), and 7 (20%) patients. Non-hematologic toxicity was mild, except for three cases of grade 2 peripheral neuropathy. All patients were assessed for response on an 'intent-to-treat' basis. Overall, five partial responses were recorded (docetaxel + gemcitabine = 3 and docetaxel + vinorelbine = 2), for a 15% (95% CI: 5%-31%) overall response rate. Only 1 of 24 (4%) patients who had received weekly dose-dense paclitaxel responded to treatment. CONCLUSIONS: The weekly docetaxel administration in combination with either gemcitabine or vinorelbine is a well-tolerated treatment for heavily pretreated advanced breast cancer patients. This approach, although sometimes capable of achieving a major response, does not seem advisable in advanced breast cancer patients refractory to both anthracyclines and paclitaxel.

Adult↗
PubMed2000

Definition of the role of chromosome 9p21 in sporadic melanoma through genetic analysis of primary tumours and their metastases. The Melanoma Cooperative Group.

Malignant melanoma (MM) is thought to arise by sequential accumulation of genetic alterations in normal melanocytes. Previous cytogenetic and molecular studies indicated the 9p21 as the chromosomal region involved in MM pathogenesis. In addition to the CDKN genes (p16/CDKN2A, p15/CDKN2B and p19(ARF), frequently inactivated in familial MM), widely reported data suggested the presence within this region of other melanoma susceptibility gene(s). To clearly assess the role of the 9p21 region in sporadic melanoma, we evaluated the presence of microsatellite instability (MSI) and loss of heterozygosity (LOH) in primary tumours as well as in synchronous or asynchronous metastases obtained from the same MM patients, using 9 polymorphic markers from a 17-cM region at 9p21. LOH and MSI were found in 27 (41%) and 11 (17%), respectively, out of 66 primary tumours analysed. In corresponding 58 metastases, MSI was found at higher rate (22; 38%), whereas a quite identical pattern of allelic deletions with 27 (47%) LOH+ cases were observed. Although the CDKN locus was mostly affected by LOH, an additional region of common allelic deletion corresponding to marker D9S171 was also identified. No significant statistical correlation between any 9p21 genetic alteration (LOH, MSI or both) and clinicopathological parameters was observed.

Adolescent↗
PubMed2000

Characterization of a DNA binding site that mediates the stimulatory effect of cyclosporin-A on type III collagen expression in renal cells.

BACKGROUND: Previous work from our laboratory demonstrated upregulation of type III collagen by cyclosporin A (CsA) in a cellular model of renal fibroblasts 'in vitro', suggesting that a mechanism of gene transcriptional activation might be responsible for collagen accumulation in renal fibrosis resulting from chronic CsA treatment. METHODS: We analysed in the same cellular model: (i) COL3A1 mRNA expression by RT-PCR; (ii) COL3A1 promoter activity by transfection of renal fibroblasts with constructs containing promoter fragments of different length fused to a reporter gene; (iii) expression of transcription factors by western blot analysis; (iv) DNA-protein binding by gel retardation assays with nuclear extracts from CsA-treated and untreated cells; and (v) site-directed mutagenesis of COL3A1 promoter to verify the role of a short DNA segment as CsA responsive element. RESULTS: CsA induced a 3-5-fold increase in COL3A1 mRNA that was paralleled by a stimulation of the COL3A1 promoter. Degradation of COL3A1 mRNA was comparable in CsA-treated and -untreated cells. The target region was first limited to a 178 bp fragment from -117 to +61 (pFV1). By gel retardation, utilizing several oligonucleotides that covered the whole length of pFV1, we detected a factor able to bind the promoter DNA (oligo 31) in nuclear extracts after 3 h treatment with CsA. The binding was absent in untreated cells and it was not detected when a 10-base mutation was introduced in oligonucleotide 31. Finally, the same substitution mutation at the site of binding of this factor abolished the stimulatory effect of CsA on COL3A1 promoter. Some transcription factors, whose potential binding sites are included in the above promoter fragment, were induced by CsA treatment either soon (3 h) or late (24-72 h) after treatment and were detected by western blot analysis. CONCLUSIONS: CsA induces the synthesis of type III collagen by stimulating a pathway leading to activation of COL3A1 promoter and upregulation of COL3A1 mRNA. A short promoter fragment, proximal to the transcription start site, is the target of CsA stimulation.

Animals↗
PubMed1999

Urokinase receptor interacts with alpha(v)beta5 vitronectin receptor, promoting urokinase-dependent cell migration in breast cancer.

Perturbation of adhesive interactions at cell-substratum and cell-cell contact sites is a critical event in the multistep process of cancer invasion. Recent studies indicate that the urokinase receptor (uPAR) is associated in large molecular complexes with other molecules, such as integrins. To test the possibility that uPAR may physically and functionally interact with vitronectin (Vn) receptors, we determined the expression level of uPAR, alpha(v)beta3, and alpha(v)beta5 Vn receptors in 10 human breast carcinomas. Here, we show the ability of uPAR to physically associate with alpha(v)beta5 in the breast carcinomas examined. The functional effects of this interaction were studied using HT1080 human fibrosarcoma and MCF-7 human breast carcinoma cell lines, both exhibiting a urokinase-dependent physical association between uPAR and alpha(v)beta5. Both cell lines respond to urokinase or to its noncatalytic amino-terminal fragment by exhibiting remarkable cytoskeletal rearrangements that are mediated by alpha(v)beta5 and require protein kinase C activity. On the contrary, binding of Vn to alpha(v)beta5 results in the protein kinase C-independent formation of F-actin containing microspike-type structures. Furthermore, alpha(v)beta5 is required for urokinase-directed, receptor-dependent MCF-7 and HT1080 cell migration. These data show that uPAR association with alpha(v)beta5 leads to a functional interaction of these receptors and suggest that uPAR directs cytoskeletal rearrangements and cell migration by altering alpha(v)beta5 signaling specificity.

Adult↗
PubMed1999

Relationship between HLA-DQ and -DR genotypes and clinical characteristics in a French population of Type 1 diabetic patients.

AIMS: The present study was designed to look for a heterogeneity in the association between Type 1 diabetes mellitus (DM) and class II alleles of major histocompatibility complex (MHC) according to clinical presentation and C-peptide secretion during the first year of the disease, in a population living in south of France. METHODS: HLA DRB1 and DQB1 genotypes were determined in 129 Caucasoid patients with Type 1 DM and compared to a control group (n = 88). In a subgroup of 46 young adult diabetic patients, basal and postglucagon C-peptide secretion was followed during the first year of the disease (at 0, 1, 3, 6, 9 and 12 months). RESULTS: The two main haplotypes associated with Type 1 DM were DRB1*04DQB1*0302 and DRB1*03DQB1*02. The genotypes DRB1* 04DQB1 *0302/DRB1*04DQB1*0302 and DRB1 *03DQB1*02/DRB1*04DQB1* 0302 were associated with an early onset of diabetes, while homozygosity for DRB1*03DQB1*02 was characterized by later onset. Levels of residual insulin secretion in patients genotyped DRB1*03DQA1*0501DQB1* 02/DRB1* 04DQA1*0301DQB1*0302 were higher than in patients genotyped DRB1* 3DQA1*0501DQB1*02/DRB1*XDQA1*XDQB1*X or DRB1* XDQA1* XDQB1*X/DRB1*XDQA1*XDQB1*X. CONCLUSIONS: This study confirms some clinical heterogeneity of Type 1 DM linked to HLA DR and DQ genotypes, and leads to a paradoxical finding: DQB1*02/ DQB1*0302 combination predisposes to an early onset in the whole population but residual secretion of insulin disappears more slowly in a subgroup of young adults with recently diagnosed diabetes. These data suggest that interrelations between MHC genotype and diabetogenic process could be different at various ages of life.

Adolescent↗
PubMed1999

Morbidity of major hepatic resections: a 100-case prospective study.

OBJECTIVE: To assess the morbidity and its main risk factors after major hepatic resection. DESIGN: Retrospective study of prospectively collected data. SETTING: University hospital, France. SUBJECTS: 100 consecutive patients who underwent major hepatic resections, 1989-95. INTERVENTIONS: Major hepatic resection, defined as resection involving 3 or more segments according to Couinaud's classification, in all cases. MAIN OUTCOME MEASURES: All complications that affected outcome or prolonged hospital stay. Risk factors identified by univariate and multivariate analysis. RESULTS: 45 patients developed at least 1 complication and 7 died. The most common complications were: pleural effusion (n = 21), hepatic failure (n = 12), and ascites (n = 9). Univariate analysis showed that the following variables were significantly related to the morbidity: age >55 years, American Society of Anesthesiologists (ASA) grade II or more, bilirubin >80 micromol/L, alkaline phosphatase activity more than double the reference range, malignant tumours, abnormal liver parenchyma, simultaneous surgical procedures, operative time >4 hours, and perioperative blood transfusion > or =600 ml. The extent of resection did not correlate with postoperative complications. Multivariate analysis showed that volume of blood transfusion > or =600 ml and simultaneous surgical procedures were the most important independent risk factors for complicated outcome. CONCLUSIONS: The morbidity associated with major hepatic resections remains high, and the main determinants of outcome are intraoperative surgeon-related factors.

Adult↗
PubMed1999

[A case of peritoneal tuberculosis. Contribution of mini-endoscopy].

BACKGROUND: Tuberculosis in the genital and peritoneal region is increasing in last years. For this reason, the high value and efficacy of laparoscopy using a small caliber endoscope for the diagnosis of this disease, which often presents no specific and heterogeneous clinical features, is underlined. METHODS: A case of peritoneal tuberculosis in a young female presenting fever, asthenia and peritoneal effusion, is reported. Blood tests, X-ray and cytological examination of the peritoneal fluid all failed to point out the right diagnosis. Then multiple biopsies of the peritoneum and the external surface of uterus and ovaries were made using laparoscopy. RESULTS: Laparoscopy clearly showed the miliary nodules. The histology showed multiple granulomas composed by inner caseous necrosis and outer layer of epithelioid histiocytes and Langhans cells, leading thus to the diagnosis of peritoneal tuberculosis. The patient, treated with streptomycin and rifampicin, five months after diagnosis, did not show any feature of tubercular disease. CONCLUSIONS: Because of its safety, laparoscopy is a very useful and powerful diagnostic technique especially in those young women presenting with painful abdominal symptoms without any clear evident cause.

Adolescent↗
PubMed1999

Establishment and growth regulation of a novel ovarian cancer cell line from a poorly-differentiated adenocarcinoma: proposal for a new treatment.

A continuously growing cultured cell line has been obtained in vitro, starting from a specimen of ascites fluid obtained from a patient with ovarian cancer, in whom a poorly-differentiated adenocarcinoma was diagnosed. This cell line, named OC-A1, is routinely grown in standard, serum-supplemented culture medium and has been fully stabilized to long-term growth and characterized for both cultural and genetic parameters. OC-A1 cells express a set of characteristics, as determined in vitro which, when compared with the in vivo primary tumor, confirm the high malignity of this cancer. In addition, karyotype analysis showed a translocation of chromosome 8 which is correlated with the amplification of c-myc oncogene. However, the expression of this oncogene was found to be significantly inhibited by a new regulatory activity, recently found to be present in a liposarcoma cell line. Conditioned medium from these cells was indeed able to inhibit the growth of OC-A1 cells, arresting their cell cycle in the G1 phase and inducing them to apoptosis. Finally, the cell programmed death appeared to be related to the expression of antioncogene p53.

Adenocarcinoma↗
PubMed1998

Detection of high mobility group I HMGI(Y) protein in the diagnosis of thyroid tumors: HMGI(Y) expression represents a potential diagnostic indicator of carcinoma.

Hyperplastic or neoplastic proliferative lesions of thyroid follicular epithelium consist of a spectrum, ranging from nodular hyperplasia to undifferentiated (anaplastic) carcinoma, and usually present as palpable thyroid nodules. Thyroid nodules are a common occurrence in the general population, but only a small proportion of them are eventually diagnosed as carcinoma. The difficulty in objectively identifying those thyroid nodules that are malignant to avoid unnecessary surgery, combined with the range and effectiveness of the available therapeutic options in those patients who do, indeed, have thyroid carcinoma, has prompted the search for tumor markers and prognostic indicators. The high mobility group I (HMGI) proteins represent a class of nuclear proteins involved in the regulation of chromatin structure and function. HMGI(Y), one of the members of this class, is expressed at high levels during embryogenesis and in malignant tumors but at generally low levels in normal adult human tissues. Previous work on a limited number of thyroid samples suggested that the detection of the HMGI(Y) proteins may provide a clinically useful diagnostic tool. To verify this assumption, we analyzed HMGI(Y) expression by a combination of immunohistochemistry and reverse transcription-PCR in 358 thyroid tissue samples that were representative of the spectrum of thyroid tumor pathology. HMGI(Y) was detectable in 18 of 19 follicular carcinomas, 92 of 96 papillary carcinomas, and 11 of 11 undifferentiated (anaplastic) carcinomas but in only 1 of 20 hyperplastic nodules, 44 of 200 follicular adenomas, and 0 of 12 normal tissue samples. The correlation between HMGI(Y) expression and a diagnosis of carcinoma was highly significant (P < 0.0001). We also prospectively collected and analyzed for HMGI(Y) expression by immunohistochemistry and reverse transcription-PCR in 12 fine needle aspiration biopsies from 10 patients who subsequently underwent surgical removal of a solitary thyroid nodule. HMGI(Y) was detectable only in the four fine needle aspiration biopsies, corresponding to the thyroid nodules that were definitively diagnosed as carcinomas after surgery (two follicular carcinomas and two papillary carcinomas). The remaining eight samples (six follicular adenomas and two samples consisting of normal follicular cells) were negative. The findings of this study confirm the differential expression of HMGI(Y) in thyroid neoplasia and indicate the HMGI(Y) protein as a potential marker for thyroid carcinoma.

Adenocarcinoma, Follicular↗
PubMed1998

A reference standard for plasma proteins is required for nutritional assessment of adult burn patients.

Plasma levels of visceral proteins (VP) are commonly used for evaluation of nutritional status. Low values observed in burn patients are caused by several factors including microvascular hyper-permeability and inflammatory processes. The aim of the study was to define a range of standard values specific to burn patients. Retrospective review: from days post-burn 12 to 43, four VP and three acute phase reactants (APR) were measured twice a week, in the plasma of 107 burn patients. From these data, standard' values were determined in respect with burn surface area (BSA) and post-burn time. The results were that the VP increase and APR decrease linearly during the study. Correlation between plasma proteins and BSA or post-burn day, change from protein to protein. Albumin and transferrin are less sensitive than prealbumin and especially retinol binding protein to variations of APR, but transferrin lacks of specificity. The conclusion of the study was that plasma levels of VP have to be compared to reference standard values. When levels lower than theoretical values are observed, simultaneous APR values (especially C reactive protein) have to be compared to their own reference standard, in order to separate nutritional from inflammatory effects.

Adult↗