PubMed Health⌕ Search

Biomedical subjects

M Provencio

Publications and source records attributed to M Provencio.

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

Mutational status of K-ras and TP53 genes in primary sarcomas of the heart.

We investigated three patients with cardiac angiosarcomas and two with cardiac rhabdomyosarcomas, all for mutations at exons 5, 6, 7 and 8 of the p53 gene and at exon 1 of K-ras. No point mutations were observed in the p53 gene in any of the five cases; however, at exon 1 of K-ras, three patients (60%) presented the same mutation at the first base of codon 13 (G to A transition). Interestingly, this mutation was detected in both rhabdomyosarcoma and angiosarcoma histologic sarcoma types.

Adult↗
PubMed1999

Presence of tumor DNA in plasma of breast cancer patients: clinicopathological correlations.

Using different molecular techniques, DNA has been detected in the plasma of cancer patients with various types of tumors. We undertook the present study to investigate the presence of plasma DNA, before mastectomy, in patients with breast cancer at diagnosis and to analyze the clinicopathological spectrum of this subgroup of patients with respect to patients without DNA with tumor characteristics. We studied 62 patients with breast cancer, who were selected sequentially after mastectomy and diagnosis of breast carcinomas. Genomic DNA extracted from tumor and normal tissues, normal blood cells, and plasma was used for molecular studies. Alterations in polymorphic markers selected because they had been found to show a high rate of alterations in breast cancer in previous studies (D17S855, D17S654, D16S421, TH2, D10S197, and D9S161), as well as mutations in the p53 gene and aberrant methylation at the first exon of p16INK4a, were used to identify and characterize tumor and plasma DNA. Thirteen clinicopathological parameters were analyzed in each patient. We identified 56 cases (90%) with at least one molecular event in tumor DNA, and 41 cases (66%) with a similar alteration in plasma DNA. Comparison of the clinicopathological parameters between patients with and without plasma DNA revealed significant differences in the axillary involvement, rate of invasive ductal carcinoma, high proliferative index, and the parameter comprised of lymph node metastases, histological grade II, and peritumoral vessel involvement. A high proportion of breast cancer patients exhibited plasma DNA at diagnosis similar to tumor DNA, and its presence correlated significantly with pathological parameters associated with a poor prognosis.

Breast↗
PubMed1999

Phase II study of ifosfamide plus vinorelbine in metastatic breast cancer patients previously treated with combination chemotherapy.

Forty-six patients were included in a phase II study to evaluate the response rate and toxicity of a combination of ifosfamide and vinorelbine in metastatic breast cancer patients previously treated with one or more regimens of chemotherapy. Treatment consisted of ifosfamide 1.6 g/m(2) IV days 1-3 (with mesna) and vinorelbine 25 mg/m(2) IV days 1 and 8, every 3 weeks up to 6 cycles. The median age was 55 years (range 40-76), the World Health Organization (WHO) performance status was 0-1 in 93% of the patients and 2 in the remaining 7%. In all, 43% had received two or more previous lines of chemotherapy, and 91% had been treated with anthracyclines. Forty-four patients were evaluable for response, and all patients for toxicity. The overall response rate was 36.4% [95% confidence interval (CI) 22.4-52.2]. Stabilization was observed in 20.4% and progression in 43.2%. The median time to progression was 25 weeks (95% CI 14-36). Median relative dose intensity (=actual received dose intensity/planned dose intensity) was 0.99 for ifosfamide and 0. 80 for vinorelbine. The main toxicity was hematological, with 63% of the patients experiencing grade 3-4 neutropenia. With a moderate toxicity, this is an active regimen that may be taken into consideration in pretreated metastatic breast cancer patients when further chemotherapy is indicated.

Adult↗
PubMed1999

Loss of heterozygosity in BRCA1 and BRCA2 markers and high-grade malignancy in breast cancer.

Loss of heterozygosity (LOH) in loci of the 17q21 and 13q12-13 regions can collaborate in the inactivation of BRCA1, BRCA2, and possibly other genes implicated in the pathogenesis of breast carcinomas. We investigate allelic losses in microsatellites of the BRCA1 and BRCA2 regions, and their correlations with seven pathologic parameters in 140 breast carcinomas. Those cases showing LOH in the region of the RB gene, 13q14, were excluded from the study. The LOH analysis was performed by amplifying DNA by PCR, using four markers of the 17q21 region (D17S856, D17S855, D17S1323, and D17S1327) and four markers of the 13q12-13 region (D13S290, D13S260, D13S310, and D13S267). LOH in the BRCA1 region was found in 47% of tumors, correlating significantly with estrogen receptor content (p = 0.025), progesterone receptors (p = 0.004), higher grade (p = 0.0008), peritumoral vessel invasion (p = 0.001), and lymph node metastases (p = 0.002). When we excluded the cases with LOH in the BRCA2 region and those not informative for it, the significance disappeared. In the BRCA2 region, a rate of LOH of 51% was found; it correlated significantly with estrogen receptor content (p = 0.002), progesterone receptors (p = 0.03), peritumoral vessel invasion (p = 0.005), higher grade (p = 0.002), and lymph node metastases (p = 0.001). When cases with BRCA1 losses and those not informative were excluded, again the significance disappeared. Concomitant losses in the BRCA1 and BRCA2 regions were found in 32% of cases, correlating significantly with lymph node metastases (p = 0.0002), estrogen receptor content (p = 0.003), progesterone receptors (p = 0.001), histologic grade (p = 0.01), and peritumoral vessel invasion (p = 0.0004). These results suggest that concomitant losses in both regions could have a functional effect, influencing the presence of a poor tumor pathophenotype in breast carcinomas.

Adenocarcinoma↗
PubMed1999

Allelic loss of the PTEN region (10q23) in breast carcinomas of poor pathophenotype.

Loss of heterozygosity (LOH) in loci of the 10q23 region that harbor the PTEN gene and mutations in the sequence of this gene have been found in several primary human tumors including breast carcinomas, suggesting that this gene could be implicated in their pathogenesis. We investigated allelic losses in microsatellites of the 10q23 region, and their correlations with nine pathologic parameters in 105 breast carcinomas. The LOH analysis was performed by amplifying DNA by PCR, using five markers of the 10q23 region (D10S1687, D10S541, D10S2491, D10S583 and D10S571). LOH in at least one marker of the PTEN region was found in 29.5% of tumors. The statistical comparison between carcinomas with and without LOH in terms of the pathologic parameters showed significant differences in age (p = 0.03), lymph node metastases (p = 0.02), and higher histological grade (p = 0.02); a trend toward significance was found for progesterone receptors (p = 0.05). LOH in an individual marker and statistically significant relationships to tumor characteristics were observed at locus D10S541 for lymph node metastases (p = 0.04), at D10S2491 (intragenic to the PTEN gene) for lymph node metastases (p = 0.02), and at D10S583 for progesterone receptors (p = 0.01) and for high grade (p = 0.03). These results suggest the PTEN gene, or other genes of the 10q23 region, could be functionally related to breast cancer, probably influencing the development of histological features associated with poor prognosis.

Breast Neoplasms↗
PubMed1999

Comparison of the long-term mortality in Hodgkin's disease patients with that of the general population.

BACKGROUND: Although Hodgkin's disease can be treated successfully, its long-term survival rate has yet to be definitely established. We compared the long-term mortality rate of patients diagnosed as having Hodgkin's disease with that of the general population. PATIENTS AND METHODS: We studied a retrospective cohort of 477 patients who received pathology-confirmed diagnoses of Hodgkin's disease between 1967 and 1993 and were treated with combined chemotherapy or radiotherapy with follow-up from the day of diagnosis. Standardised mortality ratios were computed with reference rates taken from the Spanish population. RESULTS: The follow-up was complete for 427 (89.5%) of the patients. The median follow-up time was 8 years, 133 patients (28%) died and the median survival time was 21 years. The overall survival rates were 80% at 5 years, 70% at 10 years, and 64% at 15 years after diagnosis. The standardised mortality ratios were 10.8 (95% confidence interval: 9.0-12.8, P < 0.0001) overall, 5.5 in patients in favourable stages (IA, IIA), and 15.2 in those with unfavourable stages (IB, IIB, III, IV). There was a decreasing trend in mortality by calendar period (standardised mortality ratios for 1967-1975, 1976-1974 and 1985-1993: 16.8, 10.3 and 5.1, respectively). Higher mortality was observed in all periods of follow-up after diagnosis, even after 20 years. CONCLUSIONS: Despite the improvements in treatment, mortality in Hodgkin's disease remains higher than in the general population in all disease stages, even 20 years after diagnosis.

Adolescent↗
PubMed1999

Aberrant DNA methylation of the p16INK4a gene in plasma DNA of breast cancer patients.

Hypermethylation of exon 1 of p16INK4a was examined in tumour and plasma DNA of a series of breast cancer patients. De novo methylation was observed in the tumours of eight patients (23%), and in plasma DNA in five (14%) of these eight patients. Our data show that de novo methylation of exon 1 of p16INK4a can be demonstrated in plasma DNA of breast cancer patients, a fact that provides additional evidence of the tumour-related origin of free plasma DNA in cancer patients.

Amino Acid Sequence↗
PubMed1999

Detection of loss of heterozygosity at RAD51, RAD52, RAD54 and BRCA1 and BRCA2 loci in breast cancer: pathological correlations.

Loss of heterozygosity (LOH) in loci of the 15q15.1, 12p13, 1p32, 17q21 and 13q12-13 regions may collaborate in the inactivation of RAD51, RAD52, RAD54, BRCA1, BRCA2 and possibly other genes implicated in the repair of double-stranded DNA and in DNA recombination. We investigate allelic losses in microsatellites of the RAD51, RAD52, RAD54, BRCA1 and BRCA2 regions, and their correlations with nine pathologic parameters in 127 breast carcinomas. The LOH analysis was performed by amplifying DNA by PCR, using 15 markers of the 15q15.1, 12p13.3, 1p32, 17q21 and 13q12-13 regions. LOH was found in the RAD51 region in 32% of tumours, in the RAD52 region in 16%, in RAD54 in 20% and in the BRCA1 and BRCA2 regions in 49% and 44% respectively. Significant correlations between one or more regions with concomitant LOH and pathologic parameters were observed with respect to age (P = 0.008), oestrogen receptor content (P = 0.03), progesterone receptors (P = 0.003), higher grade (P = 0.001), more advanced stage (P = 0.004) and peritumoural vessel involvement (P < 0.0001). The number of cases in which LOH was observed simultaneously in two or more regions was always higher than expected on the basis of their statistical probability, and curiously, the three patients with LOH at five regions concomitantly were under the age of 30 years. These results suggest that LOH at these regions could be related to breast cancer, and probably to a poor tumour prognosis.

Age Factors↗
PubMed1998

Loss of heterozygosity in the region including the BRCA1 gene on 17q in colon cancer.

Colon cancer has been proved to be an excellent model to identify and to study the different genetic alterations taking part in its development. BRCA1, a susceptibility gene for breast cancer, has been identified. Evidence of a significant risk for colon cancer in BRCA1-linked families has been reported. We undertook the present study to investigate the possible relation of BRCA1 and other genes on chromosome 17q21 to colon cancer. Eighty-five tumors were examined for loss of heterozygosity at seven microsatellite loci spanning the 17q21 region. Loss of heterozygosity was present in 39 (49%) of the 79 informative cases, with at least one marker. Two loci, D17S855 and D17S579, showed higher rates of allelic loss (16% and 22%, respectively) than the remaining markers. Tumors on the right side of the colon exhibited allelic loss more frequently than those on the left side. Our data suggest that BRCA1 and other genes in the 17q21 region may play an important role in the development of colon cancer.

Base Sequence↗
PubMed1998

Germ-line BRCA1 mutations in women with sporadic breast cancer: clinical correlations.

PURPOSE: Sporadic nonhereditary breast cancer is recognized as the most common form of this malignancy. Presence of germ-line mutations in the BRCA1 gene of these tumors is an infrequent event. We undertook the present study to evaluate the prevalence of germ-line mutations in patients diagnosed with sporadic breast cancer, and to delimit the clinical spectrum of this subgroup of patients with germ-line mutations and their differences with respect to patients with no evidence of BRCA1 gene mutations. METHODS: We studied 105 patients diagnosed with breast cancer, selected from among our living patients; those with carcinoma-in-situ and those with a definite family history of breast or ovarian cancer were excluded. Genomic DNA, obtained from peripheral-blood lymphocytes, was studied for BRCA1 mutations by polymerase chain reaction/single-strand conformation polymorphism (PCR-SSCP) and direct DNA sequencing. Fourteen clinicopathologic parameters were analyzed in each patient. RESULTS: Six (5.7%) frameshift mutations that corresponded to truncating proteins and three missense mutations, the functional meaning of which remains speculative, were identified. The patients with germ-line mutations were found to have a more advanced age at diagnosis, as well as a longer median survival (51 months). CONCLUSION: Women with sporadic breast cancer of late onset may display a significant incidence of germline BRCA1 mutations, which occur at a rate not previously determined in this group of patients. The presence of variations in the sequence of the BRCA1 gene could influence the longer survival observed in these patients.

Adult↗
PubMed1998

Detection of BRCA1 gene mutations in families with breast cancer patients and their healthy relatives.

Eighty-three families with two or more cases of breast and ovarian cancer were selected to evaluate the prevalence rate of BRCA1 gene mutations, and identify healthy carriers. Blood samples from patients and healthy relatives were obtained. Haplotype study of the 17q21 region using 7 polymorphic markers was performed. Mutational analysis of the coding exons of the BRCA1 gene was performed by the PCR-SSCP method and direct sequencing. We detected germline mutations (frameshift and missense) in 6 families (9.1%). Combining haplotype analysis and PCR-SSCP screening, 18 (15%) healthy female carriers were identified. The prevalence rate of germline BRCA1 gene mutations among our families with breast cancer syndrome is low, and relatives having the same haplotype for the 17q21 region as mutation-carrying patients usually display the same genomic sequence as the patients.

Breast Neoplasms↗