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C De Filippo

Publications and source records attributed to C De Filippo.

18 recordsLinked to original sources
PubMed2002

Microsatellite instability in a population of sporadic colorectal cancers: correlation between genetic and pathological profiles.

BACKGROUND: Tumours with high-frequency microsatellite instability exhibit unique genotype and phenotype features, whereas the difference between low-frequency microsatellite instability and apparently stable tumours is far from being clear. AIMS: To identify distinctive genetic and pathological characteristics of low-frequency microsatellite instability tumours. METHODS: Microsatellite instability status of 57 sporadic colorectal cancers and its correlation with genetic, pathological and clinical features was analysed. RESULTS: High frequency microsatellite instability and low-frequency microsatellite instability and apparently stable cancers were different in terms of tumour localisation (p=0.015), frequency of APC mutations (p=0.012), occurrence of Crohn's-like/lymphoid reaction (p=0.0353) and morphological evidence of origin from an adenoma (p=0.0338). Specifically, in low-frequency microsatellite instability cancers, APC mutations were very frequent (76.9%, 10/13) and a Crohn's-like/lymphoid reaction was common (38.5%, 5/13). High-frequency microsatellite instability tumours were preferentially located in the right colon and exhibited a higher frequency of loss of heterozygosity at the FHIT locus compared with low-frequency microsatellite instability and apparently stable cases (p=0.0243). Dukes' stage (p=0.0021), tumour localisation (p=0.0410) and pattern of cancer growth (p=0.0374), were the only factors affecting patient survival. However, a borderline improvement was noted in overall survival in high-frequency microsatellite instability and low-frequency microsatellite instability cancer patients (p=0.062). CONCLUSIONS: These results indicate that low-frequency microsatellite instability tumours have different genetics and histological features and suggest that they are a distinct group of colorectal cancers.

Adult↗
PubMed2002

An immunogenetic map of Lombardy (Northern Italy).

For this study we consulted the Bone Marrow Donors' Registry of Lombardy (Italy) and analyzed 43937 HLA-A,B phenotypes and 13922 HLA-A,B,DR phenotypes. We estimated the HLA-A,B and HLA-A,B,DR haplotype frequencies via the maximum-likelihood method. We analyzed the genetic structure of the 11 provinces of Lombardy by means of Principal Component Analysis and Correspondence Analysis, and estimated the variety of the different haplotypes at provincial level and the percentage of unique phenotypes at village level. We found 11189 different HLA-A,B phenotypes, 661 different HLA-A,B haplotypes and more than 4000 different HLA-A,B,DR haplotypes. We identified 20 villages, in Western Lombardy, very rich in unique/rare phenotypes. Here we report a formula which allows the identification of a putative donor matched for two haplotypes with a recipient. This result may be of great importance for the genetic study of the population of Lombardy and, even more, for bone marrow transplantation programs.

Alleles↗
PubMed2002

Mutations of the APC gene in human sporadic colorectal cancers.

BACKGROUND: Mutations of the APC gene are reported to occur frequently in sporadic colorectal adenomas and adenocarcinomas. We studied APC gene mutations in cases of human sporadic colorectal cancer in order to evaluate their correlation with pathologic characteristics and clinical prognosis. METHODS: Most of the mutations of the APC gene (95%) are nonsense or frame shift mutations, encoding for truncated APC proteins. For this reason, mutation detection of the APC gene was performed using the in vitro synthesized protein (IVSP) assay, analysing the region between nucleotide 2058 and nucleotide 5079 of the gene, containing the mutation cluster region. RESULTS: Out of 58 cases of colorectal cancer, 29 presented a mutated form of APC (mutation frequency 50%). We did not find a statistically significant correlation between APC gene mutation and age, sex, localization of the primary tumour, grading, Crohn-like lymphoid reaction or presence of residual adenoma. Tumours with low invasivity (Dukes' stages A and B) were less frequently mutated (12/27, 44.5%) than tumours of Dukes' stage C (15 out of 21, 71.4%), which developed macroscopically secondary metastasis with variable latency after surgery. Highly invasive tumours with synchronous metastases (Dukes' stage D) had, instead, a low frequency of APC mutations (20%, 2/10) (P = 0.02, compared with Dukes' stages A, B and C). CONCLUSIONS: These data suggest that more aggressive Dukes' stage D tumours develop metastasis by means of an unknown mechanism, independent of APC mutation.

Adenocarcinoma↗
PubMed2001

Antioxidant and pro-oxidant capacity of catecholamines and related compounds. Effects of hydrogen peroxide on glutathione and sphingomyelinase activity in pheochromocytoma PC12 cells: potential relevance to age-related diseases.

The antioxidant and pro-oxidant capacity of catecholamines (CA) and related compounds were analyzed using the oxygen radical absorbance capacity (ORAC) assay. In the assay 2,2'-azobis (2-amidino-propane) dihydrochloride (AAPH), a peroxyl radical generator, ROO*; H2O2-Cu2+, mainly a hydroxyl radical generator, *OH; and Cu2+ a transition metal were used. The antioxidant effect of CA and its related compounds were in the order: neurotransmitters: dopamine (DA), norepinephrine (NE) > metabolites > amino acid precursors as measured by using AAPH. The antioxidant effect of CA and related compounds as measured by using AAPH were linearly correlated with concentration, while the antioxidant effect of CA in scavenging *OH produced by H2O2-Cu2+ increased proportionally to concentration at low concentration, but after reaching a maximum declined with increasing concentration. In the presence of Cu2+, CA acted as pro-oxidant. Glutathione (GSH) acted as a pro-oxidant when H2O2-Cu2+ or when Cu2+ alone was used as an oxidant and showed much higher pro-oxidant effect than DA, which could have relevance in the vulnerability of dopaminergic neurons to oxidative stress in the aging and aging related diseases. The antioxidant capacity of CA and many related compounds seems to be correlated with the numbers of hydroxyl groups and their position on the benzoic ring. The O-methylation and sulfate conjugation of the hydroxyl substitution inactivates both the antioxidant and pro-oxidant activities of CA. Our results show that oxidative stress induced by low (5 microM) or high (300 microM) doses H2O2 in pheochromocytoma PC12 cells significantly up-regulate the activity of Mg-dependent neutral sphingomyelinase (Sase), and significantly decreased GSH.

Animals↗
PubMed2001

Slow-release pellets of sodium butyrate do not modify azoxymethane (AOM)-induced intestinal carcinogenesis in F344 rats.

Butyrate exerts anti-tumour effects in vitro, but not consistently in vivo. We previously demonstrated that the administration of slow-release gastro-resistant pellets of sodium butyrate increases apoptosis in the colon mucosa of rats, an effect which may protect against carcinogenesis. Therefore, we studied whether the administration of butyrate pellets could protect rats against experimental colon carcinogenesis. Four to 5 week old male F344 rats were fed a high-fat (HF) diet (230 g/kg corn oil w/w) and treated s.c. with two injections (one week apart) of azoxymethane (AOM) at a dose rate of 15 mg/kg body weight or saline. Rats were then divided into two groups: one group received sodium butyrate pellets mixed into the diet (1.5% w/w) for 33 weeks (150 mg butyrate/day) and the second group received the high-fat diet with no butyrate. Administration of sodium butyrate pellets in the diet did not significantly affect colon carcinogenesis: the number of intestinal tumours/rat was 1.6 +/- 0.2 in controls and 2.1 +/- 0.2 in butyrate-fed rats (means +/- SE; P = 0.22, by ANOVA), while the incidence of intestinal tumours was 79 (23/29) and 90% (27/30) in controls and in butyrate-fed rats, respectively (P = 0.29 by Fisher's exact test). The level of apoptosis in the tumours was not affected by butyrate, nor was the expression of p21(CIP), a cell cycle-related protein. In conclusion, the current study indicates that butyrate does not protect against AOM-induced colon carcinogenesis in rats.

Animals↗
PubMed2000

Effect of complex polyphenols and tannins from red wine on DNA oxidative damage of rat colon mucosa in vivo.

BACKGROUND: Dietary polyphenols have been reported to have a variety of biological actions, including anti-carcinogenic, antioxidant and anti-inflammatory activities. AIM OF THE STUDY: In the present study we have evaluated the effect of an oral treatment with complex polyphenols and tannins from red wine and tea on DNA oxidative damage in the rat colon mucosa. METHODS: Isolated colonocytes were prepared from the colon mucosa of rats treated for ten days with either wine complex polyphenols (57.2 mg/kg/d) or thearubigin (40 mg/kg/d) by oral gavage. Colonocyte oxidative DNA damage was analysed at the single cell level using a modification of the comet assay technique. RESULTS: The results show that wine complex polyphenols and tannins induce a significant decrease (-62% for pyrimidine and -57% for purine oxidation) in basal DNA oxidative damage in colon mucosal cells without affecting the basal level of single-strand breaks. On the other hand, tea polyphenols, namely a crude extract of thearubigin, did not affect either strand breaks or pyrimidine oxidation in colon mucosal cells. CONCLUSIONS: Our experiments are the first demonstration that dietary polyphenols can modulate in vivo oxidative damage in the gastrointestinal tract of rodents. These data support the hypothesis that dietary polyphenols might have both a protective and a therapeutic potential in oxidative damage-related pathologies.

Animals↗
PubMed2000

Inhibition of 1,2-dimethylhydrazine-induced oxidative DNA damage in rat colon mucosa by black tea complex polyphenols.

The effect of black tea polyphenols on 1,2-dimethylhydrazine (DMH)-induced oxidative DNA damage in rat colon mucosa has been investigated. Fischer 344 rats were treated orally with thearubigin (TR) or theafulvin (TFu) for 10 days (40 mg/kg), injected ip with DMH (20 mg/kg) or saline and sacrificed 24 hr after DMH administration. The levels of 8-hydroxy-2'-deoxyguanosine (8-OHdG) were measured in colonic mucosa DNA and expressed as a ratio relative to 2'-deoxyguanosine (2dG). Control rat mucosa had 8-OHdG values of 1.12 +/- 0.14/10(5) dG (mean +/- SEM, n=11), whereas DMH-treated rats significantly higher values (1.52 +/- 0.14/10(5) dG, n=26, P<0.05). Pretreatment of rats with TR had significantly inhibited DMH-induced oxidative DNA damage 0.99 +/- 0.09/10(5) dG, n=10, P<0.05) and a similar, although less marked, effect was observed with TFu (1.15 +/- 0.19/10(5), n=9, P=0.06). These findings confirm that DMH causes oxidative DNA damage in the colon mucosa of rats and demonstrate that this effect is prevented by the consumption of complex polyphenols from black tea.

1,2-Dimethylhydrazine↗
PubMed2000

Clinicopathologic features and FHIT gene expression in sporadic colorectal adenocarcinomas.

BACKGROUND: The putative tumour suppressor gene FHIT (fragile histidine triad) spans the common fragile site FRA3B, which is highly susceptible to breaks and deletions induced by genotoxic agents. Tumours associated with exposure to carcinogens, such as colorectal adenocarcinomas, should be particularly susceptible to alterations in the FHIT gene. We studied the frequency of FHIT alterations and their correlations with clinicopathologic features in sporadic colon carcinomas. METHODS: FHIT expression was investigated by reverse transcription polymerase chain reaction in 56 primary sporadic colorectal carcinomas. The same tumours and matched normal tissues were also investigated for loss of heterozygosity by using two markers located inside the FHIT gene. RESULTS: Twenty-nine of 56 tumours (51.8%) expressed aberrant FHIT transcripts. Four tumours had absence or nearly undetectable levels of the normal-sized FHIT transcript. Sequencing analysis of the altered transcripts showed FHIT mRNA lacking one or more exons, more frequent deletions of exons 4-5-6 or 4-5-6-7-8. At the genomic level 46.4% (13 of 28) of the cases showed alterations involving FHIT locus. We did not find any correlation between FHIT gene alterations and clinicopathologic characteristics of the tumours. CONCLUSIONS: Since the FHIT gene is frequently altered, its role in the molecular pathogenesis of sporadic colon carcinoma deserves further investigation.

Acid Anhydride Hydrolases↗
PubMed2000

Effects of black tea, green tea and wine extracts on intestinal carcinogenesis induced by azoxymethane in F344 rats.

We investigated whether polyphenolic extracts from black tea, green tea or red wine affect azoxymethane (AOM)-induced intestinal carcinogenesis. Male F344 rats were treated 10 times (1 week apart) with AOM (7.4 mg/kg, s.c.) and then allocated into groups receiving black tea, green tea or red wine extracts mixed in the diet at a dose of 50 mg/kg body weight for 16 weeks. In the rats treated with black tea or wine extracts, there were significantly fewer colorectal tumours than in controls (the mean +/- SE number of tumours/rat was 2.54 +/- 1.6 in controls, 1.54 +/- 1.4 in the black tea group, 3.2 +/- 1.9 in the green tea group and 1.63 +/- 1.6 in the wine extract group). Significantly fewer rats in the black tea and wine extract groups had adenomas than in controls (86%, 59%, 90% and 50% of rats in the control, black tea, green tea and wine extract groups, respectively, had adenomas). The tumours from the black tea group and, to a lesser extent, those from the wine group, had a significantly greater apoptotic index than tumours in controls (mean +/- SE apoptotic index: 2.92 +/- 0.25, 4.13 +/- 0.46, 2.88 +/- 0.30 and 3.72 +/- 0.46 in controls, black tea, green tea or wine extract groups, respectively). In contrast, the apoptotic index of the normal mucosa did not vary among groups. These data indicate that black tea and wine extracts, but not green tea extracts, can protect against AOM-induced colon carcinogenesis by a mechanism probably involving increased apoptosis in tumours.

Adenoma↗
PubMed2000

Detection of somatic DNA alterations in azoxymethane-induced F344 rat colon tumors by random amplified polymorphic DNA analysis.

Colon carcinogenesis induced in rats by azoxymethane (AOM) is a useful experimental model as it mimics the human adenoma-carcinoma sequence and allows the study of dietary variation and of the effects of chemopreventive substances. Alterations of specific oncogenes and tumor suppressor genes (APC and K-ras) play roles at different stages of this carcinogenesis process. Recently, it has been suggested that genomic instability is the necessary step for the generation of multiple mutations underlying the occurrence of cancer. We studied the frequency of K-ras and microsatellite instability (MSI) in 30 colorectal tumors induced by AOM (30 mg/kg) in F344 rats. We also used the random amplified polymorphic DNA (RAPD) method to identify genomic alterations in chemically induced aberrant crypt foci (ACF), adenomas and adenocarcinomas. K-ras mutations were identified in 16.7% of the cases (5/30; 9% in adenomas and 37.5% in adenocarcinomas) and MSI in 20% (6/30) of the tumors (only one sample exhibited instability at more than one locus). Of 21 primers used for the RAPD assay, six were very informative. All the analyzed tumors (16/16) showed at least one RAPD profile with lost or additional bands compared with the normal mucosa. A lower level of genomic alteration was present in the ACF analyzed (7/10). In conclusion, K-ras and MSI are not often involved in the AOM carcinogenesis in the rat, whereas extensive genomic instability is always present and can be detected using the RAPD analysis.

Adenocarcinoma↗
PubMed2000

Photopheresis in cutaneous T-cell lymphoma: five-year experience.

BACKGROUND: Cutaneous T-cell lymphoma (CTCL) includes several lymphoproliferative disorders involving mature T-lymphocyte proliferation initially confined to the cutis. These affections, after variable periods, may progress to the blood, limph nodes and visceral organs. Mycosis fungoides (MF) is the most frequent form of CTCL and has an indolent clinical course. The therapy of CTCL depends on the stage of the disease and the patient's general conditions. For advanced cases it includes chemotherapy, retinoids, and interferon-alpha. Since 1987 extracorporeal photochemotherapy (ECP), a novel immunomodulatory approach based on apheresis and photoirradiation of leukocytes, has been successfully introduced for the treatment of advanced CTCL. It can prolong survival of patients with erythrodermic CTCL without significant side effects. OBJECTIVE: To review our five-year experience with ECP in CTCL. METHODS: Since June 1994, 33 CTCL patients have been recruited for ECP, using two different regimens: two procedures on two consecutive days at four-week intervals for six months, or at two-week intervals for three months with progressive tapering in the second three-month period for the more severe forms. Six patients received ECP with IFN-alpha. ECP was done using the photopheresis UVAR system and UVAR XTS (Therakos, West Chester, Pa) and always with 8-MOP liquid formulation injected directly into the buffy coat bag. Lymphocytes in peripheral blood were immunophenotypically characterized for each patient and every ECP session. RESULTS: All patients tolerated ECP well, without significant side effects. Thirty patients are clinically evaluable (at least three ECP cycles). A favourable clinical response was obtained in 80.9% (16/21) of MF patients (complete response 33%, partial response 47.6%) and in 66% (6/9) of patients in the Sézary's syndrome phase (complete response 33.3%, partial response 33.3%). Five of the six patients given IFN-alpha as adjunctive therapy had a PR and one a CR. Four patients are in CR without therapy at follow-ups of 46, 20, 10 and 8 months. There have been no changes in the peripheral lymphocyte immunophenotype during the follow-up. In 19/30 patients the CD95 antigen, correlated with cellular apoptosis, was expressed and was frequently associated with a good clinical response. CONCLUSIONS: In our experience ECP achieved favourable clinical responses in 73% of patients, in monotherapy or in combination with IFN-alpha, without significant side effects.

Adult↗
PubMed1998

Mutations of the Apc gene in experimental colorectal carcinogenesis induced by azoxymethane in F344 rats.

We investigated in the rat the role of the Apc gene, which is mutated in familial adenomatous polyposis and sporadic colon cancer in the process leading from normal colonic mucosa to aberrant crypt foci (ACF) and finally to adenomas and adenocarcinomas. We analysed mutations in exon 15 of the rat Apc gene using in vitro synthesized protein assay in 66 ACF and in 28 colon tumours induced by azoxymethane. No Apc mutations were found in ACF, whereas five mutations were found in the tumours. The data suggest that mutations of the Apc gene are associated with the transition from ACF to adenoma and adenocarcinoma and not from normal mucosa to ACF.

Adenocarcinoma↗
PubMed1997

The use of mechanical prostheses in native aortic valve endocarditis.

BACKGROUND AND AIMS OF THE STUDY: The optimal aortic valve substitute in cases of active native valve endocarditis (NVE) remains controversial. This report summarizes our experience with the surgical treatment of active aortic NVE using only mechanical prostheses. METHODS: Between January 1988 and January 1996, 20 patients underwent aortic valve replacement for active NVE. There were 17 men and three women. Mean age was 46.5 years (range eight to 63 years). Thirteen patients were in NYHA class IV and seven in class V. Streptococci were isolated in eight cases, while no causative micro-organism could be identified in seven patients. All operations were performed on urgent (n = 13) or emergency (n = 7) bases. A mechanical valve was implanted in all cases and radical resection of the infected tissues performed using different techniques. All patients were followed up at our institution. Two-dimensional color Doppler studies were performed one month after surgery and at six-month intervals after the first year. Transesophageal echocardiography (TEE) was performed at discharge, six months after surgery and yearly thereafter. RESULTS: No patient died in hospital. Mean follow up was 30.5 months, during which time three patients died, though none from endocarditis-related causes. Endocarditis recurred only one (5%). TEE demonstrated a normally functioning aortic prosthesis in 15 cases and trivial paravalvular leakage in two. CONCLUSIONS: Mechanical prostheses represent a safe aortic valve substitute in cases of acute native valve endocarditis. When radical resection of all the infected areas is performed, the incidence of endocarditis recurrence is acceptable. The concept that homografts are the valve substitute of choice in endocarditis cases cannot be supported by this study.

Adolescent↗
PubMed1991

[Histiocytic necrotizing lymphadenitis or Kikuchi and Fujimoto's disease. A case report].

We describe a case of necrotizing histiocytic lymphadenitis or Kikuchi and Fujimoto disease, a rare lymphadenopathy of unknown etiology usually striking young women. It was formerly described in Japan, and subsequently in other countries and in Italy as an anatomo-clinical entity. The disease has a favourable prognosis, therefore it has to be considered differently from other lymphadenopathies with severe prognosis whose anatomo-pathological differential features were analyzed by the authors. The case here observed differs from other cases described in literature because of the presence of a perilymphadenitic component.

Diagnosis, Differential↗
PubMedDate not supplied

[Increase of beta 2-microglobulin in drug addicts with anti-HIV antibodies and high risk of AIDS].

The beta 2-Microglobulin is a polypeptide present on the surface membrane of both B and T cells and is integrated into the structure of HLA antigenes. The beta 2-Microglobulin concentration have been used as a reliable indicator of glomerular and tubular function of the kidney. Increased serum concentration of beta 2-Microglobulin are observed also in lymphoproliferative disorders with high cell proliferation rates. More recently, increased concentration of beta 2-Microglobulin was shown in patients with anti-HIV antibodies with or without symptomatic AIDS. We have determined beta 2-Microglobulin in 61 subjects: 40 between the ages of 25 and 35 and seemingly healthy, 21 patients between the ages of 22 and 32 and intravenous drug abuser with anti-HIV antibodies and at high-risk for AIDS. In all subjects we have tested: BUN, creatinine, beta 2-Microglobulin and T4/T8 ratio. In 40 subjects as normal controls, beta 2-Microglobulin average was means = 1.07 mg/L (SD = 0.39), T4/T8 ratio average: means = 1.06 (SD = 0.119). In 21 patients drug abuser with anti-HIV antibodies, the beta 2-Microglobulin average was cleanly increased: means = 4.72 mg/L (SD = 2.23), the T4/T8 ratio average cleanly decreased: means = 0.54 (SD = 0.21). We believe the beta 2-Microglobulin quantitation, even if not specific for patient with symptomatic AIDS, used in conjunction with other laboratory tests, principally T4/T8 ratio, will be a useful marker for recognizing persons with possible asymptomatic AIDS who are members of populations known to be at high-risk for AIDS.

Acquired Immunodeficiency Syndrome↗