PubMed Health⌕ Search

Biomedical subjects

Barbara Pasini

Publications and source records attributed to Barbara Pasini.

15 recordsLinked to original sources
PubMed2006

Mutational screening of the RB1 gene in Italian patients with retinoblastoma reveals 11 novel mutations.

Retinoblastoma (RB, OMIM#180200) is the most common intraocular tumour in infancy and early childhood. Constituent mutations in the RB1 gene predispose individuals to RB development. We performed a mutational screening of the RB1 gene in Italian patients affected by RB referred to the Medical Genetics of the University of Siena. In 35 unrelated patients, we identified germline RB1 mutations in 6 out of 9 familial cases (66%) and in 7 out of 26 with no family history of RB (27%). Using the single-strand conformational polymorphism (SSCP) technique, 11 novel mutations were detected, including 3 nonsense, 5 frameshift and 4 splice-site mutations. Only two of these mutations (1 splice site and 1 missense) were previously reported. The mutation spectrum reflects the published literature, encompassing predominately nonsense or frameshift and splicing mutations. RB1 germline mutation was detected in 37% of our cases. Gross rearrangements outside the investigated region, altered DNA methylation, or mutations in non-coding regions, may be the cause of disease in the remainder of the patients. Some cases, e.g. a case of incomplete penetrance, or variable expressivity ranging from retinoma to multiple tumours, are discussed in detail. In addition, a case of pre-conception genetic counselling resolved by rescue of banked cordonal blood of the affected deceased child is described.

Base Sequence↗
PubMed2006

Mutation analysis of SDHB and SDHC: novel germline mutations in sporadic head and neck paraganglioma and familial paraganglioma and/or pheochromocytoma.

BACKGROUND: Germline mutations of the SDHD, SDHB and SDHC genes, encoding three of the four subunits of succinate dehydrogenase, are a major cause of hereditary paraganglioma and pheochromocytoma, and demonstrate that these genes are classic tumor suppressors. Succinate dehydrogenase is a heterotetrameric protein complex and a component of both the Krebs cycle and the mitochondrial respiratory chain (succinate:ubiquinone oxidoreductase or complex II). METHODS: Using conformation sensitive gel electrophoresis (CSGE) and direct DNA sequencing to analyse genomic DNA from peripheral blood lymphocytes, here we describe the mutation analysis of the SDHB and SDHC genes in 37 patients with sporadic (i.e. no known family history) head and neck paraganglioma and five pheochromocytoma and/or paraganglioma families. RESULTS: Two sporadic patients were found to have a SDHB splice site mutation in intron 4, c.423+1G>A, which produces a mis-spliced transcript with a 54 nucleotide deletion, resulting in an 18 amino acid in-frame deletion. A third patient was found to carry the c.214C>T (p.Arg72Cys) missense mutation in exon 4 of SDHC, which is situated in a highly conserved protein motif that constitutes the quinone-binding site of the succinate: ubiquinone oxidoreductase (SQR) complex in E. coli. Together with our previous results, we found 27 germline mutations of SDH genes in 95 cases (28%) of sporadic head and neck paraganglioma. In addition all index patients of five families showing hereditary pheochromocytoma-paraganglioma were found to carry germline mutations of SDHB: four of which were novel, c.343C>T (p.Arg115X), c.141G>A (p.Trp47X), c.281G>A (p.Arg94Lys), and c.653G>C (p.Trp218Ser), and one reported previously, c.136C>T, p.Arg46X. CONCLUSION: In conclusion, these data indicate that germline mutations of SDHB and SDHC play a minor role in sporadic head and neck paraganglioma and further underline the importance of germline SDHB mutations in cases of familial pheochromocytoma-paraganglioma.

Adolescent↗
PubMed2006

Incidental carcinomas in prophylactic specimens in BRCA1 and BRCA2 germ-line mutation carriers, with emphasis on fallopian tube lesions: report of 6 cases and review of the literature.

The identification of germ-line mutations in 2 genes (BRCA1 and BRCA2) responsible for the majority of hereditary ovarian cancers has led an increasing number of women carriers of these mutations to undergo prophylactic oophorectomy (PO) to reduce their risk of subsequent ovarian carcinoma. A large number of unexpected, clinically occult neoplasms are thus being discovered. Up to December 2004, the Medical Genetics Service of the National Cancer Institute in Milan, Italy, has tested 756 probands from breast and/or ovarian cancer families for BRCA1 and BRCA2 germ-line mutations. Molecular screening of family members led to the identification of 344 female carriers of BRCA1 (239) or BRCA2 (105) germ-line mutations. Of the 186 potentially eligible women (37 of whom had tested positive for BRCA1 and 13 for BRCA2 mutation), 50 (26.8%) chose to undergo PO. Six clinically occult primary gynecologic malignancies (2 stage IIIC serous carcinomas of the ovary, 3 in situ serous carcinomas of the fallopian tube, and 1 stage IIB invasive serous carcinoma of the fallopian tube) and 1 occult ovarian metastasis from breast carcinoma were identified in the PO specimens of 7 women (all BRCA1 mutated). Four of the patients with occult primary gynecologic cancers are alive without disease 129, 87, 38, and 7 months after PO, respectively. One of the 2 patients with primary ovarian cancer and the single patient with tubal invasive carcinoma are alive with recurrent disease 83 and 20 months after PO, respectively. In addition, one of the patients whose PO specimen did not show any malignancy presented with stage IIIC tubal carcinoma 77 months after PO. The relatively high number of tubal neoplasms found at PO in this group of patients underlines the linkage between mutation and the risk of developing tubal cancer, and stresses the need to include removal of the entire tubes at the time of PO and of thoroughly evaluating the specimens at the microscopic level. The upstaging of all 3 invasive carcinomas after staging surgery, and the late recurrence and persistence of 2 of them despite treatment indicate that small size of the tumors should not preclude therapy.

Adult↗
PubMed2005

Effect of pregnancy as a risk factor for breast cancer in BRCA1/BRCA2 mutation carriers.

Early age at first birth and multiparity have been associated with a decrease in the risk of breast cancer in women in the general population. We examined whether this relationship is also present in women at high risk of breast cancer due to the presence of a mutation in either of the 2 breast cancer susceptibility genes, BRCA1 or BRCA2. We performed a matched case-control study of 1,260 pairs of women with known BRCA1 or BRCA2 mutations, recruited from North America, Europe and Israel. Women who had been diagnosed with breast cancer were matched with unaffected control subjects for year of birth, country of residence, and mutation (BRCA1 or BRCA2). Study subjects completed a questionnaire detailing their reproductive histories. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived by conditional logistic regression. Among BRCA1 carriers, parity per se was not associated with the risk of breast cancer (OR for parous vs. nulliparous = 0.94; 95% CI = 0.75-1.19; p = 0.62). However, women with a BRCA1 mutation and 4 or more children had a 38% decrease in breast cancer risk compared to nulliparous women (OR = 0.62; 95% CI = 0.41-0.94). In contrast, among BRCA2 carriers, increasing parity was associated with an increased risk of breast cancer; women with 2 or more children were at approximately 1.5 times the risk of breast cancer as nulliparous women (OR = 1.53; 95% CI = 1.01-2.32; p = 0.05). Among women with BRCA2 mutations and who were younger than age 50, the (adjusted) risk of breast cancer increased by 17% with each additional birth (OR = 1.17; 95% CI = 1.01-1.36; p = 0.03). There was no significant increase in the risk of breast cancer among BRCA2 carriers older than 50 (OR for each additional birth = 0.97; 95% CI = 0.58-1.53; p = 0.92). In the 2-year period following a birth, the risk of breast cancer in a BRCA2 carrier was increased by 70% compared to nulliparous controls (OR = 1.70; 95% CI = 0.97-3.0). There was a much smaller increase in breast cancer risk among BRCA2 carriers whose last birth was 5 or more years in the past (OR = 1.24; 95% CI = 0.79-1.95). A modest reduction in risk of breast cancer was observed among BRCA1 carriers with 4 or more births. Among BRCA2 carriers, increasing parity was associated with a significant increase in the risk of breast cancer before age 50 and this increase was greatest in the 2-year period following a pregnancy.

Adolescent↗
PubMed2005

A comparison of bilateral breast cancers in BRCA carriers.

BACKGROUND: Women with breast cancer and a BRCA mutation have a high risk of developing a contralateral breast cancer. It is generally believed that the two cancers represent independent events. However, the extent of concordance between the first and second tumors with respect to hormone receptor expression and other pathologic features is unknown. PURPOSE: To determine the degree of concordance of estrogen receptor (ER) status, tumor grade, and histology in tumors from women with bilateral breast cancer and a BRCA mutation. SUBJECTS AND METHODS: Women with a history of bilateral invasive breast cancers were selected from an international registry of women with BRCA1 or BRCA2 mutations. Medical records were reviewed to document the characteristics of each cancer and the treatments received. RESULTS: Data were available for 286 women with bilateral breast cancer and a BRCA mutation (211 BRCA1; 75 BRCA2). The mean interval between first and second tumor was 5.1 years. The two tumors were concordant more often than expected for ER status (P < 0.0001) and for grade (P < 0.0001), but not for histology (P = 0.55). The ER status of the first tumor was highly predictive of the ER status of the second tumor (odds ratio, 8.7; 95% confidence interval, 3.5-21.5; P < 0.0001). Neither age, menopausal status, oophorectomy nor tamoxifen use was predictive of the ER status of the second tumor. CONCLUSIONS: There is strong concordance in ER status and tumor grade between independent primary breast tumors in women with a BRCA mutation. The excess concordance may be due to common risk factors, genetic variation, or the existence of a preneoplastic lesion that is common to both tumors.

Adult↗
PubMed2004

Atypical epithelial proliferation in fallopian tubes in prophylactic salpingo-oophorectomy specimens from BRCA1 and BRCA2 germline mutation carriers.

Although growing numbers of tubal carcinomas in carriers of BRCA1 and BRCA2 germline mutations have been reported, very little is known about the nature and frequency of their possible precursor lesions. The aim of this study is to investigate the occurrence of atypical proliferative tubal lesions in grossly normal fallopian tubes from 26 women with BRCA1 and BRCA2 germline mutations who underwent prophylactic salpingo-oophorectomy and whose ovaries were histologically negative for carcinoma. Fallopian tubes from 49 women who had undergone hysterectomy with salpingo-oophorectomy for uterine leiomyoma served as controls. In the 22 BRCA1-mutated women, there were two in situ carcinomas and two atypical hyperplasias of the tubal epithelium. The tubes of the BRCA2-mutated women and of the 49 control women did not show any atypical proliferation. The frequency of proliferative lesions of the tubal epithelium, including in situ carcinoma, appears to be increased in BRCA1 mutation carriers. Removal and thorough examination of the fallopian tubes at the time of surgical prophylaxis for ovarian cancer is therefore recommended.

Cell Division↗
PubMed2003

Different expressivity of BRCA1 and BRCA2: analysis of 179 Italian pedigrees with identified mutation.

Mutations in BRCA1 and BRCA2 show different expressivity with respect to cancer risk, and allelic heterogeneity may be present in both genes. We collected 179 pedigrees with identified germline mutation (104 BRCA1 and 75 BRCA2), ascertained in six collaborating centers of the Italian Consortium for Hereditary Breast and Ovarian Cancer. Significant heterogeneity was detected for several variables, and a logistic regression model including age of diagnosis in the proband, presence of ovarian cancer in the family, presence of prostate or pancreatic cancer in the family, and presence of male breast cancer in the family proved to be effective in predicting the presence of a mutation in a gene rather than the other. Excess of familial aggregation of both breast and ovarian cancer was observed in both genes. Proportion of ovarian cancer was increased in the 5' portion of BRCA1, and presence of prostate or pancreatic cancer in a family was correlated with presence of ovarian cancer in BRCA2.

Breast Neoplasms↗
PubMed2002

Oral contraceptives and the risk of breast cancer in BRCA1 and BRCA2 mutation carriers.

BACKGROUND: Oral contraceptive use has been associated with an increase in the risk of breast cancer in young women. We examined whether this association is seen in women at high risk of breast cancer because they carry a mutation in one of two breast cancer susceptibility genes, BRCA1 and BRCA2. METHODS: We performed a matched case-control study on 1311 pairs of women with known deleterious BRCA1 and/or BRCA2 mutations recruited from 52 centers in 11 countries. Women who had been diagnosed with breast cancer were matched to control subjects by year of birth, country of residence, mutation (BRCA1 or BRCA2), and history of ovarian cancer. All study subjects completed a questionnaire about oral contraceptive use. Odds ratios (ORs) and 95% confidence intervals (CIs) were derived by conditional logistic regression. All statistical tests were two-sided. RESULTS: Among BRCA2 mutation carriers, ever use of oral contraceptives was not associated with an increased risk of breast cancer (OR = 0.94, 95% CI = 0.72 to 1.24). For BRCA1 mutation carriers, ever use of oral contraceptives was associated with a modestly increased risk of breast cancer (OR = 1.20, 95% CI = 1.02 to 1.40). However, compared with BRCA1 mutation carriers who never used oral contraceptives, those who used oral contraceptives for at least 5 years had an increased risk of breast cancer (OR = 1.33, 95% CI = 1.11 to 1.60), as did those who used oral contraceptives before age 30 (OR = 1.29, 95% CI = 1.09 to 1.52), those who were diagnosed with breast cancer before age 40 (OR = 1.38, 95% CI = 1.11 to 1.72), and those who first used oral contraceptives before 1975 (OR = 1.42, 95% CI = 1.17 to 1.75). CONCLUSIONS: Among BRCA1 mutation carriers, women who first used oral contraceptives before 1975, who used them before age 30, or who used them for 5 or more years may have an increased risk of early-onset breast cancer. Oral contraceptives do not appear to be associated with risk of breast cancer in BRCA2 carriers, but data for BRCA2 carriers are limited.

Adolescent↗
PubMed2002

High prevalence of the G101W germline mutation in the CDKN2A (P16(ink4a)) gene in 62 Italian malignant melanoma families.

CDKN2A germline mutation frequency estimates are commonly based on families with several melanoma cases. When we started counseling in a research setting on gene susceptibility analysis in northern and central Italy, however, we mostly found small families with few cases. Here we briefly characterize those kindred, estimate CDKN2A/CDK4 mutation test yields, and provide indications on the possibility of implementing formal DNA testing for melanoma-prone families in Italy. In September 1995 we started genetic counseling in a research setting at our Medical Genetics Center. Screening for CDKN2A/CDK4 mutations was performed on families with two melanoma patients, one of whom was younger than 50 years at onset, the other complying with one of the following: 1) being a first-degree relative, 2) having an additional relative with pancreatic cancer, or 3) having multiple primary melanomas. Sixty-two of 67 (80%) melanoma cases met our criteria. Four previously described CDKN2A mutations (G101W, R24P, V126D, and N71S) were found in 21 of the 62 families (34%) with a high prevalence of G101W (18/21). The percentage of families with two melanoma cases/family harboring a mutation was low (7%, 2/27), but rose to 45% (9/20) if one of the melanoma patients carried multiple melanomas or if pancreatic cancer was present in that family. In the 15 families with three melanoma cases the presence of a mutation was higher (67%, 10/15) and reached 100% in the 4 families with four or more melanoma cases. Our results suggest that CDKN2A/CDK4 counseling-based mutational analysis may be reasonably efficient also for families with two melanoma cases, if one patient carries multiple melanomas or if pancreatic cancer is present in the family.

Adolescent↗
PubMed2002

Effect of fenretinide on ovarian carcinoma occurrence.

OBJECTIVE: The aim of this study was to update the effect of fenretinide, a synthetic vitamin A analogue proposed for chemoprevention, on the occurrence of ovarian carcinoma. METHODS: Data were obtained from a randomized clinical trial for the prevention of second breast cancer. For the present investigation, events of interest were new primary carcinomas of the ovary arising in the fenretinide or the no-treatment (control) arm. The probability of carrying a BRCA germ-line mutation was assessed in women with ovarian carcinoma according to G. Parmigiani et al. (1998, Am J Hum Genet 62, 145-58). RESULTS: Fenretinide reduced ovarian carcinoma occurrence during the 5-year intervention period (0 versus 6 cases in the fenretinide and control arm, P = 0.0327). This effect was no longer evident after the 5-year intervention period (6 versus 4 cases, P = 0.7563). Therefore with median observation time of 121 months, a total of 6 carcinomas of the ovary occurred in the fenretinide group and 10 in the control group. The probability of carrying a BRCA mutation was lower for women with ovarian carcinoma in the treatment arm. CONCLUSION: Fenretinide treatment was associated with a lower incidence of ovarian carcinoma during the intervention period but such a protective effect seems to disappear after treatment. Furthermore, a possible protective effect of fenretinide in BRCA-mutated women was suggested. Further studies on fenretinide for the prevention of ovarian carcinoma particularly in women with genetic susceptibility appear necessary.

Adult↗
PubMed2002

Lack of SYT-SSX fusion transcripts in malignant peripheral nerve sheath tumors on RT-PCR analysis of 34 archival cases.

The translocation t(X;18) is currently regarded as a specific molecular marker of synovial sarcoma (SS). Recently, however, it has been reported that malignant peripheral nerve sheath tumors expressed this marker in 75% of the cases. To test independently this iconoclastic claim, a molecular analysis for the detection of the SYT-SSX fusion genes was carried out using archival material of 34 consecutive cases diagnosed as malignant peripheral nerve sheath tumors and treated in our Institute from 1998 to 2000. In four of these cases, the molecular analysis on fixed tissues was supplemented with an analysis on fresh frozen tissue. RNA extracted from formalin-fixed paraffin-embedded tissue blocks was evaluated for the presence of SYT-SSX1 and SYT-SSX2 fusion transcripts by RT-PCR. This analysis was extended to a wide variety of normal tissues simultaneously extracted and equally processed. Only two of the cases studied harbored SYT-SSX1 and SYT-SSX2 fusion transcripts, respectively. The diagnostic reevaluation of these two cases in light of the molecular data disclosed that one had the features of a monophasic SS and the other was compatible with that entity. Both of these tumors were strongly immunoreactive for bcl-2, confirming the diagnostic utility of this marker in this instance. Our results reaffirm the specificity of SYT-SSX for SS and suggest that an opposite claim made in a recent study may have been due to a faulty interpretation of the molecular results caused by a contamination of the samples.

Adolescent↗
PubMed2002

RET mutation profile and variable clinical manifestations in a family with multiple endocrine neoplasia type 2A and Hirschsprung's disease.

BACKGROUND: RET proto-oncogene germ line mutations are associated with the inherited multiple endocrine neoplasia type 2 syndromes (MEN 2), as well as with familial and sporadic Hirschsprung's disease (HSCR). In this study, we report a family in which the MEN 2A and the HSCR phenotypes are associated with a single point mutation in exon 10 of the RET proto-oncogene. Furthermore, we have investigated polymorphic sequence variants of the RET proto-oncogene. METHODS: Family members were tested for RET proto-oncogene mutations in exons 10, 11, 13, 14, 15, and 16 by double-gradient denaturing-gradient gel electrophoresis, nucleotide sequence analysis, and restriction endonuclease digestion of polymerase chain reaction products. The status of exon 2 and 13 polymorphic sites was investigated by EagI and TaqI digestion in 12 selected patients. RESULTS: A heterozygous C618R mutation of RET exon 10 was identified in 12 family members. Five out of 7 children with mildly elevated pentagastrin-stimulated calcitonin levels who carried the mutation underwent prophylactic thyroidectomy before the age of 12. C-cell hyperplasia (CCH) was found in 4 children and a microscopic medullary thyroid carcinoma (MTC) in an 8-year-old female. Neither CCH nor MTC was found in the only family member affected with HSCR, an 8-year-old male. This patient inherited the mutated RET allele from his mother, who had MTC but not HSCR, together with a rare allelic variant at codon 45 of RET exon 2. CONCLUSIONS: This report of a newly-described kindred with the infrequent clinical association between MEN 2A and HSCR confirms the risk of the latter phenotype among carriers of RET exon 10 cysteine codon mutations. Nevertheless, the influence of other genetic or environmental factors cannot be excluded.

Adult↗
PubMedDate not supplied

Breast MRI screening in patients with increased familial and/or genetic risk for breast cancer: a preliminary experience.

AIMS AND BACKGROUND: Breast cancer is the most common cancer affecting women, and it is associated with or due to a genetic predisposition in 5%-10% of the cases. Owing to the higher risk of developing breast cancer and the early onset of the disease in women proved or suspected to be carriers of a breast cancer susceptibility gene, a dedicated screening should be offered as a less invasive approach with the otherwise suggested prophylactic mastectomy. This should be optimized in order to overcome the limitations of conventional breast imaging with the application of new technologies such as breast magnetic resonance imaging. METHODS: A diagnostic protocol for routine control in patients at high risk of developing breast cancer has been prepared. Within a 7-month period, 23 patients suspected or proved to carry a breast cancer susceptibility gene underwent breast magnetic resonance imaging. RESULTS: Four breast cancers were identified with breast magnetic resonance imaging. In these cases, mammography was negative because of the density of the parenchyma or for its fibroglandular pattern. Ultrasound was negative in 2 cases, not specific for malignancy in 1 case, and considered as only possibly malignant but with biopsy recommendation on the basis of magnetic resonance findings in the last one. Clinical analysis was positive for a mass in 2 cases. CONCLUSIONS: The accuracy of breast magnetic resonance imaging is known to be higher than that of conventional imaging in the study of breast parenchyma. High spatial resolution, no breast density influence and multiplanarity can give more detailed information about the smaller lesions and the right extension of the disease. Preliminary studies where breast magnetic resonance imaging is performed in addition to mammography within this group of patients are encouraging. We also believe that the application of breast magnetic resonance imaging can be very useful in the detection of cancer as early as possible with the aim to obtain the highest chance of survival after treatment.

Adult↗
PubMedDate not supplied

Prophylactic thyroidectomy in MEN 2A syndrome.

Genetic testing is the appropriate procedure in MEN 2A syndrome for the early diagnosis of medullary carcinoma even at a preclinical stage. Prophylactic total thyroidectomy represents the standard preventive and therapeutic surgical approach in the treatment of medullary thyroid carcinoma in MEN 2A syndrome. Our experience has confirmed the presence of CCH and medullary thyroid carcinoma even in clinically negative patients, in agreement with reports in the literature.

Adult↗