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Biomedical subjects

E Friedman

Publications and source records attributed to E Friedman.

At least 91 records · Page 5Linked to original sources

Significantly lower rates of BRCA1/BRCA2 founder mutations in Ashkenazi women with sporadic compared with familial early onset breast cancer.

To delineate the clinical, genetic and family history attributes in Jewish Ashkenazi women with early onset (< 42 years) breast cancer we genotyped such women for the three predominant Jewish Ashkenazi mutations in BRCA1 (185delAG and 5382insC) and BRCA2 (6174delT). The study cohort was composed of 172 women diagnosed with breast cancer at or before the age of 42 years, obtained from the oncology department registry. Mutations were identified in 54 women (31%). Of 79 women with a positive family history for breast and/or ovarian cancer, and 93 with no such family history, 45 (57%) and 9 (10%), respectively, were mutation carriers (chi2 = 46; P < 0.001). Contralateral breast cancer occurred in 15 of 54 mutation carriers (28%) compared with 8 of 118 (7%) non-carriers (chi2= 14; P < 0.001). Early onset breast cancer per se is a weak predictor of finding germ line mutation(s) in BRCA1 and BRCA2, unless associated with a positive family history and/or bilaterality.

Adult↗

Immunohistochemical analyses of sporadic and familial (185delAG carriers) ovarian cancer in Israel.

A single germ line mutation in BRCA1, (185delAG) is detected in a substantial portion of Jewish Israeli patients with ovarian cancer. Whether disease phenotypes differ in BRCA1 mutation carriers and sporadic cases is presently a subject for debate. To gain insight into this issue, we analysed tumours from 65 Jewish women with ovarian cancer, 29 (45%) were 185delAG BRCA1 mutation carriers, and 36 (55%) were non-carriers of any of the predominant Jewish mutations in BRCA1 or BRCA2 (sporadic). In 19/29 mutation carriers (66%) diagnosis was made prior to age 60 years, compared with 14/36 (39%) of the non-carriers (P=0.03; Yates corrected P=0.06). Low malignant potential ('borderline') tumours were detected less frequently among carriers (2/29; 7%) than non-carriers (9/36; 25%) (P=0.03; one tail P=0.05). Immunohistochemical analysis in invasive carcinoma (n=54) showed that 17/27 carriers (63%) and 18/27 non-carriers (67%) had positive nuclear staining with a p53 antibody. In 4/27 carriers (15%) and 3/25 non-carriers (12%), 25% or more of the tumour cells stained positive for Ki-67, an insignificant difference. Results were not altered by including borderline tumours (n=11) in these analyses. We conclude that the rate of TP53 inactivation and proliferative index in ovarian cancer, are similar for 185delAG BRCA1 mutation carriers and sporadic cases.

Aged↗

Association of the C677T polymorphism in the MTHFR gene with breast and/or ovarian cancer risk in Jewish women.

The C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene is associated with reduced enzyme activity, hyperhomocysteinaemia and increased risk for atherosclerosis in homozygotes. We examined the frequency of this mutation and its association with disease pattern in 491 Jewish women with either sporadic (n = 355; 72%) or hereditary (n = 136; 28%) breast and/or ovarian cancer and in 69 asymptomatic BRCA1/2 mutation carriers, genotyped for the three predominant Jewish founder BRCA1/2 mutations (185delAG, 5382insC and 6174delT). 677T homozygotes were equally distributed among women with sporadic breast and/or ovarian cancer (71/355; 20.0%) and among BRCA1/2 mutation carriers (43/205; 21.0%) (P=non-significant). 677T homozygotes were equally distributed among women diagnosed with breast cancer prior to (22/122; 18.0%) and after 42 years of age (42/243; 17.3%). Among BRCA1/2 carriers, the rate of 677T homozygotes in manifesting cancer (32/136; 23.5%) and asymptomatic individuals (11/69; 15.9%) was not significantly different. The rate of 677T homozygotes (24/72; 33.3%) was higher (P=0.0026) among women with bilateral breast cancer and those with both breast and ovarian carcinoma than among those with unilateral breast cancer (64/365; 17.5%). Differences in morbidity (one versus multiple breast/ovarian tumours) are mainly attributed to 677T homozygosity and partly to BRCA1/2 mutations. Confirmation of these data, namely, that the 677T allele is significantly more common in cases of bilateral breast cancer or combined breast and ovarian cancer would have important clinical implications.

Adult↗

Two p16 (CDKN2A) germline mutations in 30 Israeli melanoma families.

Germline mutations in the p16 (CDKN2A) tumour suppressor gene have been linked to inherited predisposition to malignant melanoma (MM). Variable frequencies of p16 germline mutations were reported in different collections of melanoma families but it can be as high as 50%. Here we describe the results of p16 mutation screening in 30 melanoma kindreds in Israel. The entire coding region of the p16 gene, including exons 1, 2 and 3, flanking exon/intron junctions, and a portion of the 3' untranslated (UTR) region of the gene were examined by single-stranded conformation polymorphism (SSCP) analysis and direct sequencing. Two p16 germline mutations were identified: G101W, which has been previously observed in a number of melanoma kindreds, and G122V, a novel missense mutation. Thus, the frequency of mutations identified in this collection of Israeli families was 7%. Functional analysis indicated that the novel G122V variant retained some capacity to interact with cyclin dependent kinases (CDKs) in vitro, yet it was significantly impaired in its ability to cause a G1 cell cycle arrest in human diploid fibroblasts. This partial loss of function is consistent with the predicted impact of G122V substitution on the 3-dimensional structure of the p16 protein.

Adolescent↗

Association of the I1307K APC mutation with hereditary and sporadic breast/ovarian cancer: more questions than answers.

The frequency of the APC I1307K mutation and its association with disease pattern was examined in 996 Ashkenazi women consisting of individuals with either sporadic (n = 382) or hereditary (n = 143) breast and/or ovarian cancer; asymptomatic BRCA1/2 mutation carriers (185delAG, 5382insC and 6174delT) (n= 53) and healthy controls (n= 418). The I1307K allele was equally distributed among women with sporadic (17/382; 4.6%) and inherited (10/143; 7%) breast and/or ovarian cancer irrespective of their being diagnosed before or after 42 years of age and among asymptomatic (7/53; 13.2%) and cancer manifesting BRCA1/2 carriers (10/143; 7%). Taken together, the prevalence of the I1307K allele was significantly higher in BRCA1/2 carriers compared to non-BRCA1/2 carriers (17/196; 8.7% and 40/800, 5%; respectively). The high prevalence of the I1307K allele among BRCA1/2 carriers is not associated with increased cancer risk but seems to be genetically connected because of Jewish ancestry.

Adenomatous Polyposis Coli Protein↗

The rate of the founder Jewish mutations in BRCA1 and BRCA2 in prostate cancer patients in Israel.

Inherited predisposition occurs in 5-10% of all prostate cancer (CaP) patients, but the genes involved in conferring genetic susceptibility remain largely unknown. Several lines of evidence indicate that germline mutations in BRCA1 and BRCA2 might be associated with an increased risk for CaP. Three mutations in these two genes (185delAG and 5382InsC (BRCA1) and 6174delT (BRCA2) occur in about 2.5% of the general Ashkenazi population, and the 185delAG BRCA1 mutation, in up to 1% of non-Ashkenazi Jews. In order to assess the contribution of these germline mutations to prostate cancer in Jewish Israeli patients, we tested 174 unselected prostate cancer patients (95 of Ashkenazi origin) for these mutations by PCR amplification and modified restriction enzyme digests. Patient's age range was 45-81 years (median 66), and in 24 (14.4%) the disease was diagnosed prior to 55 years of age. Nineteen (11%) and 12 (6.9%) patients had a first or second degree relative with CaP or breast cancer, respectively. Overall, five mutation carriers were detected: 2/152 (1.3%) 185delAG, 2/104 (2%) 5382InsC, and 1/158 (0.6%) 6174delT. In all carriers, the disease was diagnosed after the age of 55, and only one of them had a family history of breast and CaP. In addition, no allelic losses at the BRCA1 locus were demonstrated in 17 patients with a family history of CaP, using seven microsatellite markers. We conclude that the rate of the predominant Jewish BRCA1 and BRCA2 mutations in CaP patients does not significantly differ from that of the general population, and that mutational inactivation of the BRCA1 is rare in familial CaP. Thus, germline BRCA1 and BRCA2 mutations probably contribute little to CaP occurrence, to inherited predisposition, and to early onset disease in Jewish individuals.

Aged↗

Genetic analyses of male breast cancer in Israel.

Male breast cancer is a rare disorder, and little is known about the molecular mechanisms associated with the tumorigenic process. We genotyped 31 Jewish Israeli males with breast cancer for the predominant Jewish BRCA1 (185delAG, 5382InsC) and BRCA2 (6174delT) germline mutations: 11 individuals from high-risk families and 20 patients unselected for family history of cancer. Two patients of the high-risk group (18.2%) displayed germline mutations: one harbored the 185delAG BRCA1 mutation, and the other the 6174delT mutation in BRCA2. None of the unselected patients displayed any mutation. In 2 patients, complete mutation analysis of the BRCA2 gene did not reveal any disease-associated mutations. We conclude that the predominant Jewish germline mutations in BRCA1/BRCA2 contribute to male breast cancer in Israel, primarily in Ashkenazi individuals with a family history of cancer.

Adult↗

The founder mutations in the BRCA1, BRCA2, and ATM genes in Moroccan Jewish women with breast cancer.

To gain insight into the molecular mechanisms underlying the inherited predisposition to breast cancer in non-Ashkenazi Jews, we genotyped 54 Jewish Moroccan women with breast cancer, unselected for family history of cancer, for the predominant Jewish mutations in BRCA1, BRCA2, and ATM. One patient (2%) was found to have the 185de1AG BRCA1 mutation, none was a carrier of the 6174delT BRCA2 mutation, and 2/54 (4%) were heterozygous for the ATM mutation. These rates were not significantly different from the rates in the general non-Ashkenazi population. These preliminary data may indicate that the predominant Jewish mutations in BRCA1, BRCA2, and ATM genes contribute little, if any, to breast cancer predisposition and risk among Moroccan Jews.

Adult↗

Age-related decreases in lymphocyte protein kinase C activity and translocation are reduced by aerobic fitness.

This study investigated the effects of advancing age and long-term aerobic fitness on lymphocyte protein kinase C (PKC) activity and translocation. Lymphocytes were obtained from young (20-36 years old) and older (61-78 years old) healthy men who were either aerobically conditioned or deconditioned. Both baseline PKC activity and the response of this enzyme to the direct PKC stimulating agent, phorbol 12-myristate, 13-acetate (PMA) or to the mitogen, phytohaemagglutinin (PHA), were measured in partially purified extracts of cytosolic and membranous fractions of lymphocytes. Basal PKC activity, PMA-induced redistribution of PKC, and PHA-induced enhancement of PKC activity were reduced among older subjects in both lymphocyte cytosolic and membranous fractions. However, the magnitudes of these reductions were smaller among the older subjects who were aerobically fit. Lymphocyte PKC activity and translocation may be biological markers of aging, and the maintenance of aerobic fitness into later life may serve to slow the rate at which activation of this enzyme declines during senescence.

Adult↗

Stress fractures in the Israeli defense forces from 1995 to 1996.

This study, encompassing 2591 Israeli soldiers, characterized Israeli soldiers with stress fractures to profile individuals who are prone to experience stress fractures: 318 with clinically and scintigraphically proven high grade stress fractures; 237 soldiers with symptoms but with normal scintigraphy; and 2036 soldiers with no symptoms. Soldiers with high grade stress fractures weighed less (68.4 +/- 7.9 kg versus 70.5 +/- 12.4 kg), smoked less, and reported fewer previous stress fractures, had fewer reports of stress fractures in their family histories, and had fewer incidences of bone diseases than did control subjects. Serum levels of bone specific alkaline phosphatase and osteocalcin were elevated in patients with high grade stress fractures compared with control subjects with no symptoms: 37.6 versus 26.2 units/L, and 10.8 versus 8.8 ng/mL, respectively. Levels of 25-hydroxy vitamin D were lower in patients with high grade stress fractures (25.3 ng/mL) than in control subjects (29.8 ng/mL). This study revealed that several parameters can distinguish soldiers with high grade stress fractures, but their predictive value and precise pathogenetic role remain unclear.

Adult↗

p53 and WAF1 polymorphisms in Jewish-Israeli women with epithelial ovarian cancer and its association with BRCA mutations.

OBJECTIVE: To investigate whether polymorphic p53 and WAF1 alleles are associated with clinical, demographic and histopathological features and BRCA mutation in women with ovarian cancer. DESIGN: A cross-sectional study. POPULATION: Two hundred and twenty-one nonselected Israeli women with epithelial ovarian cancer. METHODS: DNA was analysed for known polymorphisms in intron 3 (a 16 nucleotide single repeat) and intron 6 (a G to A change at nucleotide 13,494) of the p53 gene, the S31R polymorphism in the WAF1 gene, and for three predominant Jewish mutations in the BRCA genes (185delAG and 5382insC in BRCA1, and 6174delT in BRCA2). MAIN OUTCOME MEASURE: The rate of polymorphic p53 and WAF1 alleles and their association with BRCA mutation, ethnic origin, age and stage at diagnosis, and family history of cancer. RESULTS: Of the tested women, 72 (32.6%) were either BRCA1 (n = 57) or BRCA2 (n = 15) mutation carriers. Sixty-eight of 213 (31.9%) were heterozygous for intron 3 polymorphism, 67/193 (34.7%) for intron 6 polymorphism, and 22/154 (14.3%) for S31R of the WAF1 gene. The p53 and WAF1 polymorphism rate did not differ between BRCA mutation carriers and noncarriers. No significant association between specific p53 or WAF1 genotypes, and clinical, histopathological or demographic variables was observed. CONCLUSION: In Jewish-Israeli women with sporadic and familial ovarian cancer, p53 or WAF1 polymorphisms do not seem to affect the phenotype.

Adult↗

Mechanism of decreased adenosine protection in reperfusion injury of aging rats.

The purpose of this study was to determine whether the protective effects of adenosine on myocardial ischemia-reperfusion injury are altered with age, and if so, to clarify the mechanisms that underlie this change related to nitric oxide (NO) derived from the vascular endothelium. Isolated perfused rat hearts were exposed to 30 min of ischemia and 60 min of reperfusion. In the adult hearts, administration of adenosine (5 micromol/l) stimulated NO release (1. 06 +/- 0.19 nmol. min(-1). g(-1), P < 0.01 vs. vehicle), increased coronary flow, improved cardiac functional recovery (left ventricular developed pressure 79 +/- 3.8 vs. 57 +/- 3.1 mmHg in vehicle, P < 0.001; maximal rate of left ventricular pressure development 2,385 +/- 103 vs. 1,780 +/- 96 in vehicle, P < 0.001), and reduced myocardial creatine kinase loss (95 +/- 3.9 vs. 159 +/- 4.6 U/100 mg protein, P < 0.01). In aged hearts, adenosine-stimulated NO release was markedly reduced (+0.42 +/- 0.12 nmol. min(-1). g(-1) vs. vehicle), and the cardioprotective effects of adenosine were also attenuated. Inhibition of NO production in the adult hearts significantly decreased the cardioprotective effects of adenosine, whereas supplementation of NO in the aged hearts significantly enhanced the cardioprotective effects of adenosine. The results show that the protective effects of adenosine on myocardial ischemia-reperfusion injury are markedly diminished in aged animals, and that the loss in NO release in response to adenosine may be at least partially responsible for this age-related alteration.

Adenosine↗

Microsatellite instability in sporadic parathyroid adenoma.

Parathyroid adenomas are usually benign uniglandular tumors, and inactivation of several tumor suppressor genes, notably the MEN 1 gene, or activation of oncogenes have been implicated in the tumorigenesis. Genomic instability, indicative of the involvement of DNA mismatch repair genes, has not been previously described in parathyroid adenomas. A single large parathyroid adenoma was resected from an 8.5-yr-old Brazilian patient with no personal or family history of other endocrinopathies. Analysis of paired tumor-nontumor DNA using 23 microsatellite markers, located on chromosomes 1, 10, and 11 was carried out. Microsatellite instability was detected in nine markers (D1S191, D1S212, D1S413, D1S2848, RET, D11S901, D11S903, INSR, and INT2), whereas no allelic loss was detected with any of the analyzed markers. Immunohistochemical analysis of retinoblastoma protein expression revealed low levels of expression, but no histopathological signs of malignancy. We conclude that in this single, apparently sporadic parathyroid adenoma, DNA mismatch repair genes might be involved in parathyroid tumorigenesis.

Adenoma↗

MEN1 gene mutation analysis in Italian patients with multiple endocrine neoplasia type 1.

Multiple endocrine neoplasia type 1 (MEN 1) is a familial syndrome characterized by parathyroid, enteropancreatic and pituitary tumors. The gene responsible for this syndrome is localized at chromosomal 11q13 region and DNA markers from this region cosegregate with the disease. The recent identification of the MEN1 gene, encoding for a protein termed menin of 610 amino acids, allowed mutational screening to be performed both in affected families and sporadic cases. To date many different heterozygous mutations, spreading across all the encoding sequence, have been identified in MEN 1 patients with no apparent mutational hot spots or genotype-phenotype correlation. To analyze the genetic alterations of the MEN1 gene occurring in Italian patients we performed mutational screening by Denaturant Gradient Gel Electrophoresis followed by sequencing of exons 2-10 of the MEN1 gene in 27 Italian MEN 1 families and in five sporadic cases. We identified 17 different heterozygous mutations in 60% of analyzed cases. Twelve of these mutations are novel. Two mutations each occurred twice in unrelated families but no evidence of genotype-phenotype correlation can be established for these families. The extension of genetic diagnosis to asymptomatic family members allowed the identification of 10 MEN1 mutant gene carriers, one newly described and nine previously detected by linkage analysis with DNA markers from the 11q13 region. Our findings add new information to the diversity of mutations occurring in the MEN1 gene and confirm that the mutational screening of MEN 1 is a useful approach to detect individuals at higher risk of developing MEN 1-associated tumors.

DNA Mutational Analysis↗

The presence of HPV 16, 18 and p53 immunohistochemical staining in tumor tissue of Israeli Jewish women with cervical and vulvar neoplasia.

The incidence of cervical neoplasia in Israeli Jewish women is persistently lower, while that of vulvar carcinoma is comparable to that in other populations. The aim of the present investigation was to assess the prevalence of HPV and of immunohistochemically detected mutant p53 in Israeli Jewish women with cervical and vulvar neoplasia compared with other populations. Tissue sections from formalin-fixed paraffin-embedded blocks of ten patients with CIN III, 29 with invasive squamous cell carcinoma, three with adenocarcinoma and 14 with invasive vulvar carcinoma, were examined for the presence of HPV 16 and HPV 18 DNA by PCR amplification, and for mutant p53 protein by immunohistochemical staining. HPV negative cases were re-examined with a sensitive primer. HPV DNA was detected in eight patients with CIN III and in 23 patients with invasive squamous carcinoma. In the remaining cervical squamous neoplasia tissue analysis with the sensitive primer could not be done. HPV DNA was also detected in two patients with adenocarcinoma and in nine (64.2%) patients with vulvar carcinoma. Positive p53 immunohistochemical staining was found only in one CIN III patient, in six (20.7%) squamous carcinoma and in 11 (78.6%) vulvar carcinoma patients. Of the p53 immunohistochemical staining positive tissues, two with cervical carcinoma and six with vulvar carcinoma were also HPV-positive. The prevalence of HPV and of positive p53 immunohistochemical staining in our series of Israeli Jewish women with cervical and vulvar neoplasia is similar to that in other populations, suggesting that the etiological factors are probably also alike.

Adult↗

Transcription control and neuronal differentiation by agents that activate the LXR nuclear receptor family.

LXR and PPAR receptors belong to the nuclear receptor superfamily of transcriptional activating factors. Using ligand-dependent transcription assays, we found that 5-tetradecyloxy-2-furancarboxylic acid (TOFA) transactivates chimeric receptors composed of the glucocorticoid receptor DNA binding domain and the ligand binding regions of PPARalpha, PPARbeta (NUC-1) and LXRbeta (NER) receptors. In the same assays, ligands for PPARs (oleic acid, WY-14643 and L-631,033) and LXRs (hydroxycholesterols) maintain their respective receptor selectivity. TOFA and hydroxycholesterols also stimulate transcription from a minimal fibrinogen promoter that is under the control of AP-1 or NF-kappaB transcription factor binding sites. In addition to their effects on transcription, these LXRbeta activators induce neuronal differentiation in rat pheochromocytoma cells. TOFA and the natural LXR agonist, 22 (R)-hydroxycholesterol, stimulate neurite outgrowth in 55 and 28% of cells, respectively. No neurite outgrowth was induced by the related 22(S)-hydroxycholesterol, which does not activate the LXR family. These results suggest that the hydroxycholesterol signaling pathway has a complex effect on transcription that mediates the activity of TOFA and hydroxycholesterol on neuronal differentiation in pheochromocytoma cells.

Animals↗