Quantitative Three-Dimensional Assessment of the Pharmacokinetic Parameters of Intra- and Peri-tumoural Tissues on Breast Dynamic Contrast-Enhanced Magnetic Resonance Imaging.

We aimed to assess the feasibility of three-dimensional (3D) segmentation and to investigate whether semi-quantitative dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters are associated with traditional prognostic factors for breast cancer. In addition, we evaluated whether both intra-tumoural and peri-tumoural DCE parameters can differentiate the breast cancers that are more aggressive from those that are less aggressive. Consecutive patients with newly diagnosed invasive breast cancer and structural breast MRI (3.0 T) were included after informed consent. Fifty-six patients (mean age, 57 years) with mass lesions of > 7 mm in diameter were included. A semi-automatic image post-processing algorithm was developed to measure 3D pharmacokinetic information from the DCE-MRI images. The kinetic parameters were extracted from time-signal curves, and the absolute tissue contrast agent concentrations were calculated with a reference tissue model. Markedly, higher intra-tumoural and peri-tumoural tissue concentrations of contrast agent were found in high-grade tumours (n = 44) compared to low-grade tumours (n = 12) at every time point (P = 0.006-0.040), providing positive predictive values of 90.6-92.6% in the classification of high-grade tumours. The intra-tumoural and peri-tumoural signal enhancement ratios correlated with tumour grade, size, and Ki67 activity. The intra-observer reproducibility was excellent. We developed a model to measure the 3D intensity data of breast cancers. Low- and high-grade tumours differed in their intra-tumoural and peri-tumoural enhancement characteristics. We anticipate that pharmacokinetic parameters will be increasingly used as imaging biomarkers to model and predict tumour behavior, prognoses, and responses to treatment.

Finnish Fanconi anemia mutations and hereditary predisposition to breast and prostate cancer.

Mutations in downstream Fanconi anemia (FA) pathway genes, BRCA2, PALB2, BRIP1 and RAD51C, explain part of the hereditary breast cancer susceptibility, but the contribution of other FA genes has remained questionable. Due to FA's rarity, the finding of recurrent deleterious FA mutations among breast cancer families is challenging. The use of founder populations, such as the Finns, could provide some advantage in this. Here, we have resolved complementation groups and causative mutations of five FA patients, representing the first mutation confirmed FA cases in Finland. These patients belonged to complementation groups FA-A (n = 3), FA-G (n = 1) and FA-I (n = 1). The prevalence of the six FA causing mutations was then studied in breast (n = 1840) and prostate (n = 565) cancer cohorts, and in matched controls (n = 1176 females, n = 469 males). All mutations were recurrent, but no significant association with cancer susceptibility was observed for any: the prevalence of FANCI c.2957_2969del and c.3041G>A mutations was even highest in healthy males (1.7%). This strengthens the exclusive role of downstream genes in cancer predisposition. From a clinical point of view, current results provide fundamental information of the mutations to be tested first in all suspected FA cases in Finland.

PREDICT Plus: development and validation of a prognostic model for early breast cancer that includes HER2.

BACKGROUND: Predict (www.predict.nhs.uk) is an online, breast cancer prognostication and treatment benefit tool. The aim of this study was to incorporate the prognostic effect of HER2 status in a new version (Predict+), and to compare its performance with the original Predict and Adjuvant!. METHODS: The prognostic effect of HER2 status was based on an analysis of data from 10 179 breast cancer patients from 14 studies in the Breast Cancer Association Consortium. The hazard ratio estimates were incorporated into Predict. The validation study was based on 1653 patients with early-stage invasive breast cancer identified from the British Columbia Breast Cancer Outcomes Unit. Predicted overall survival (OS) and breast cancer-specific survival (BCSS) for Predict+, Predict and Adjuvant! were compared with observed outcomes. RESULTS: All three models performed well for both OS and BCSS. Both Predict models provided better BCSS estimates than Adjuvant!. In the subset of patients with HER2-positive tumours, Predict+ performed substantially better than the other two models for both OS and BCSS. CONCLUSION: Predict+ is the first clinical breast cancer prognostication tool that includes tumour HER2 status. Use of the model might lead to more accurate absolute treatment benefit predictions for individual patients.

Combined risk effects of IDE and NEP gene variants on Alzheimer disease.

Polymorphisms in genes encoding amyloid beta-peptide (A beta)-degrading enzymes neprilysin (NEP) and insulin-degrading enzyme (IDE) individually affect the susceptibility to Alzheimer disease (AD) among the Finnish population. Here we show that a combination of risk genotypes for NEP and IDE genes leads to a higher susceptibility to AD. Individuals with the combination of risk genotypes for NEP and IDE conferred a threefold higher susceptibility to AD when compared with individuals not carrying these genotypes. Although no significant interaction was observed between NEP and IDE genes, these data suggest that NEP and IDE exhibit an additive risk effect in AD.

Beta-amyloid deposition in brains of subjects with diabetes.

AIM: A causative association between diabetes mellitus (DM) and Alzheimer's disease (AD) has been suggested based on clinical and epidemiological studies. One hypothesis is that the link between DM and AD is related to the function of insulin-degrading enzyme (IDE), an enzyme that degrades not only insulin and pancreatic amylin but also beta-amyloid (Abeta). Thus, in diabetics, insulin and Abeta might compete for IDE and this might lead to an increase in Abeta. The objective of this study was to test the hypothesis that hyperinsulinaemia can elevate Abeta levels and thus contribute to AD pathology in humans. METHODS: Neuropathological examination was carried out employing conventional and immunohistochemical (IHC) methods of the brains obtained post mortem from 701 aged subjects. RESULTS: The loads of IHC/Abeta, silver stained neuritic plaques (NP) and neurofibrillary tangles (NFT) were significantly higher in subjects carrying the Apolipoprotein E e4 allele. In contrast, the loads of Abeta, NPs and NFT in the brains were not influenced by hyperglycaemia when comparing 134 diabetic with 567 non-diabetic subjects. CONCLUSIONS: We conclude that the hypothesis that hyperinsulinaemia would significantly elevate the Abeta load and thus increase the extent of AD pathology cannot be supported. Our result challenges the claim that DM is a direct risk factor of developing AD. Thus further studies on pathological lesions in demented diabetics should be conducted.

Screening for BRCA1 and BRCA2 mutations in Eastern Finnish breast/ovarian cancer families.

Familial aggregation is thought to account for 5-10% of all breast cancer cases, and high penetrance breast and ovarian cancer susceptibility genes BRCA1 and BRCA2 explain < or =20% of these. Hundreds of mutations among breast/ovarian cancer families have been found in these two genes. The mutation spectrum and prevalence, however, varies widely among populations. Thirty-six breast/ovarian cancer families were identified from a population sample of breast and ovarian cancer cases among a relatively isolated population in Eastern Finland, and the frequency of BRCA1/BRCA2 germline mutations were screened using heteroduplex analysis, protein truncation test and sequencing. Five different mutations were detected in seven families (19.4%). Two mutations were found in BRCA1 and three in BRCA2. One of the mutations (BRCA2 4088insA) has not been detected elsewhere in Finland while the other four, 4216-2nt A-->G and 5370 C-->T in BRCA1 and 999del5 and 6503delTT in BRCA2, are recurrent Finnish founder mutations. These results add to the evidence of the geographical differences in distribution of Finnish BRCA1/BRCA2 mutations. This screen also provides further evidence for the presumption that the majority of Finnish BRCA1/BRCA2 founder mutations have been found and that the proportion of BRCA1/BRCA2 mutations in Finnish breast/ovarian cancer families is around 20%.

Polymorphisms in neprilysin gene affect the risk of Alzheimer's disease in Finnish patients.

OBJECTIVES: Neprilysin (NEP) is an amyloid beta-peptide (Abeta) degrading enzyme expressed in the brain, and accumulation of Abeta is the neuropathological hallmark in Alzheimer's disease (AD). In this study we investigated whether polymorphisms in the NEP gene have an effect on the risk for AD. METHODS: The frequencies of seven single nucleotide polymorphisms (SNPs) and apolipoprotein E (APOE) were assessed in 390 AD patients and 468 cognitively healthy controls. Genotypes of the study groups were compared using binary logistic regression analysis. Haplotype frequencies of the SNPs were estimated from genotype data. RESULTS: Two SNPs, rs989692 and rs3736187, had significantly different allelic and genotypic frequencies (uncorrected p = 0.01) between the AD and the control subjects and haplotype analysis showed significant association between AD and NEP polymorphisms. CONCLUSION: Taken together, these findings suggest that polymorphisms in the NEP gene increase risk for AD and support a potential role for NEP in AD.

Possible association of nicastrin polymorphisms and Alzheimer disease in the Finnish population.

The authors previously reported that genetic variation in the gene coding for nicastrin (NCSTN) modified risk for familial early-onset Alzheimer disease (AD) in a Dutch population-based sample. Risk was highest in patients without an APOE epsilon4 allele. Here, they evaluated if NCSTN polymorphisms increased risk of AD in the eastern Finnish population. A significant difference in one haplotype was observed in AD patients without the APOE epsilon4 allele.

Polymorphisms in the CYP19 gene confer increased risk for Alzheimer disease.

BACKGROUND: Brain aromatase may be neuroprotective by increasing the local estrogen levels in injured neurons. Aromatase is encoded by the CYP19 gene located at 15q21.1, a chromosomal region in linkage disequilibrium (LD) with Alzheimer disease (AD) in this sample. OBJECTIVE: To investigate whether nine single-nucleotide polymorphisms (SNP) spanning the CYP19 gene were associated with AD. METHODS: Three hundred ninety-four patients were compared with 469 nondemented control subjects using single-locus and haplotype approaches. Haplotypes were identified using the expectation/maximization algorithm and latent class analysis, which included additional information on age, sex, and APOE polymorphism. RESULTS: Allelic and genotypic frequencies for three adjacent SNP differed between AD and control groups. Both haplotype approaches identified an approximately 60% increase (p = 0.02) in the risk of AD for one haplotype and similar levels of excess risk irrespective of APOE polymorphism and gender. CONCLUSION: Genetic variation in the brain aromatase gene may modify the risk for AD.

Lack of association between C-850T polymorphism of the gene encoding tumor necrosis factor-alpha and polycystic ovary syndrome.

In the present study, we determined whether genetic variability in the gene encoding tumor necrosis factor-alpha (TNF-alpha) contributes to individual differences in susceptibility to the development of polycystic ovary syndrome (PCOS). The study involved 87 Caucasian Finnish women with PCOS and 115 healthy control women who were genotyped for the C-850T polymorphism in the TNF-alpha gene promoter. Analysis by chi(2) was used to assess genotype and allele frequency differences between PCOS women and controls. A similar genotype distribution for the C-850T polymorphism was observed in the two groups, with the frequency of the variant T allele being 8.6% in the PCOS group and 9.6% in the control group (p = 0.862). Accordingly, the profile of genotype frequencies was similar in the groups. The observed profiles of allele and genotype frequencies confirm an equilibrium state between C-850T polymorphism and PCOS and suggest that polymorphism of the TNF-alpha gene is unlikely to contribute to the risk of PCOS.

Midlife income, occupation, APOE status, and dementia: a population-based study.

OBJECTIVE: To examine the relationship between socioeconomic factors and APOE carrier status on the development of dementia. METHODS: Subjects were derived from random, population-based samples previously studied in surveys carried out in 1972, 1977, 1982, and 1987. After an average follow-up of 21 years, 1449 (73%) subjects aged 65 to 79 years were re-examined in 1998. The diagnosis of dementia among the nonparticipants was derived from patient records of the local hospitals and primary health care clinics. RESULTS: Low income level at old age was related to dementia, but low income level at midlife was not a risk factor for dementia. Dementia was also associated with decreasing income level, from midlife to old age 21 years later, when dementia was diagnosed. A sedentary occupation (office, service, or intellectual work) was associated with a decreased risk for dementia among participants; however, when the nonparticipants were included in the analysis, the associations were no longer significant. Low educational level and the APOE epsilon4 allele independently increased the risk for dementia. CONCLUSIONS: Reduction in income level during follow-up and low income level at old age might be the consequence of a dementing process rather than being associated with risk evolution of dementia.

Molecular genetic analysis of the alpha-synuclein and the parkin gene in Parkinson's disease in Finland.

Two mutations in the alpha-synuclein gene and various mutations in the parkin gene are associated with familial Parkinson's disease (PD). The present study was performed to analyse if mutations in these genes could be detected in Finnish patients with familial PD. The subjects comprised 22 unrelated patients with familial PD. The molecular genetic analysis consisted of sequence analysis of the non-coding and coding exons of the alpha-synuclein gene and screening of eight point mutations in the parkin gene. In addition, a total of 67 controls and 45 patients with sporadic PD were included in the association analysis on polymorphism of the alpha-synuclein gene. Screened point mutations in the parkin gene were not detected. Sequencing of the coding exons 2-6 of the alpha-synuclein gene did not reveal any mutations or polymorphisms. However, three novel alterations in the T10A7 sequence at the 5' end of the non-coding exon 1' of the alpha-synuclein gene were found. The frequencies of the exon 1' polymorphic genotypes or alleles between familial PD patients and control subjects revealed no statistically significant differences. No association for sporadic PD was observed. The results do not support a role for the alpha-synuclein gene or point mutations of the parkin gene in familial PD in our sample.

Seladin-1 transcription is linked to neuronal degeneration in Alzheimer's disease.

Seladin-1 is a gene recently shown to be down-regulated in brain regions selectively degenerated in Alzheimer's disease. The sequence of seladin-1 shares similarities with flavin-adenine-dinucleotide-dependent oxidoreductases and it has been found to protect cells from apoptotic cell death. In this work, we show that the transcription of seladin-1 is selectively down-regulated in the brain areas affected in Alzheimer's disease. The down-regulation in seladin-1 transcription was associated with hyperphosphorylated tau seen as linkage to immunohistochemically detected paired helical filament tau, neuritic plaques and neurofibrillary tangles. In contrast, no association was found between seladin-1 transcription and beta-amyloid deposition when analyzing human samples or tissue from transgenic animals. Furthermore, the relative transcription of seladin-1 was found to fluctuate during aging in the transgenic mouse model of Alzheimer's disease. The fluctuation was enhanced by Alzheimer's disease causing mutations in presenilin-1 and amyloid precursor protein genes. Finally, seladin-1 transcription was found to be up-regulated in mouse N2a cells induced to undergo apoptosis with okadaic acid. The results presented here indicate that seladin-1 transcription is selectively down-regulated in brain regions vulnerable to Alzheimer's disease and this down-regulation is associated with the hyperphosphorylation of tau protein.

Genome-wide linkage disequilibrium mapping of late-onset Alzheimer's disease in Finland.

BACKGROUND: AD is a complex neurodegenerative disorder comprising several disease-associated chromosome loci. To find novel susceptibility genes for late-onset AD, a population-based genome-wide search using linkage disequilibrium (LD) mapping approach has been performed. METHOD: Forty-seven patients with late-onset AD and 51 age-matched control subjects were carefully chosen from the same geographic area in eastern Finland, where the population is descended mainly from a small group of original founders. These subjects were initially genotyped with 366 polymorphic microsatellite markers, and a follow-up analysis was performed with additional microsatellite markers for those chromosome loci found to be associated with AD. RESULTS: Initial genome-wide screening revealed 21 chromosomal loci significantly associated with AD in addition to the 13q12 locus described previously. Subsequent comparison of single-allele frequencies of the microsatellite markers in the AD and control groups indicated the presence both of possible risk alleles (odds ratio [OR] > 1) and of possible protective alleles (OR < 1). Screening of the LD regions with additional microsatellite markers revealed seven chromosomal loci where more than one microsatellite marker was associated with AD (1p36.12, 2p22.2, 3q28, 4p13, 10p13, 18q12.1, and 19p13.3) in addition to the 13q12 locus. CONCLUSIONS: These genome-wide LD screening data suggest that several AD-associated chromosomal loci exist, which may encompass novel susceptibility genes for late-onset AD. Therefore, extensive screening of the genes located in the vicinity of these LD regions is necessary to elucidate their role in AD.

Insertion-deletion polymorphism in the gene for angiotensin-converting enzyme is associated with obstetric cholestasis but not with preeclampsia.

OBJECTIVE: Our purpose was to investigate the contribution of angiotensin-converting enzyme insertion-deletion polymorphism in the development of obstetric complications. STUDY DESIGN: In a retrospective case-control study, angiotensin-converting enzyme insertion-deletion polymorphism was investigated in a control group of healthy women (n = 115) and in a group of women diagnosed with preeclampsia (n = 133) and obstetric cholestasis (n = 57). Polymerase chain reaction detection of insertion-deletion polymorphism was used to determine the presence of the two angiotensin-converting enzyme alleles in the groups; the frequencies in the general population in our area are presented for comparison. RESULTS: The frequency of the D allele was 43.9% among women with obstetric cholestasis and 27% among healthy fertile women, which is close to the rate in the general population in our area (28%). The odds ratio for obstetric cholestasis associated with the DD genotype was 2.12 (95% CI, 1.08-4.12) compared with the pooled II and ID genotypes (P = .03). Neither the ID genotype distributions nor the allele frequencies differed significantly between preeclamptic and normotensive pregnancies (P = .36). CONCLUSION: The present data indicate that the DD genotype is a genetic marker associated with an elevated risk of obstetric cholestasis, but this polymorphism of the angiotensin-converting enzyme gene is unlikely to play any significant role in preeclampsia.

Apolipoprotein E alleles in women with pre-eclampsia.

AIMS: To investigate the frequency of three apolipoprotein E (apoE) alleles among women with pre-eclampsia. METHODS: The presence of the three most common apoE alleles (epsilon 2, epsilon 3, epsilon 4) was determined by polymerase chain reaction-restriction fragment length polymorphism in two groups of women: healthy pregnant women (n = 91) and pregnant women with a diagnosis of pre-eclampsia (n = 133). In addition, the frequencies of the alleles in the general population in this area are presented for comparison. RESULTS: The frequency of the apo epsilon 4 allele was 18.4% among women with pre-eclampsia and 18.7% among healthy pregnant women (Fisher's exact test; p = 0.941), which is close to the rate in the general population in this area (19%). None of the apolipoprotein E genotypes was significantly over-represented, and homozygous genotype epsilon 4 was not associated with more severe clinical disease than were the other genotypes. CONCLUSION: The observed profiles of allele and genotype frequencies confirm an equilibrium state between apoE polymorphism and pre-eclampsia and suggest that apoE does not play a major role in the development of pre-eclampsia.

Maternal susceptibility locus for obstetric cholestasis maps to chromosome region 2p13 in Finnish patients.

BACKGROUND: Obstetric cholestasis, attributed to maternal hypersensitivity to estrogens, is a pregnancy-specific disorder characterized by pruritus and biochemical cholestasis in the second or third trimester of pregnancy. The pathophysiology of the disorder is incompletely understood, but the familial nature of the disease has long been recognized. Carriership of long-chain 3-hydroxyacyl-coenzyme A dehydrogenase (LCHAD) deficiency has been reported to be associated with an increased risk of obstetric cholestasis and the gene is located in the p23 region of chromosome 2. METHODS: On the basis of this information, we conducted population-based linkage disequilibrium (LD) screening to find potential cholestasis-associated loci on chromosome 2. The study was carried out in 47 unrelated control women and in 45 cholestatic women, eight of whom had a positive family history. RESULTS: During initial screening with chromosome 2-specific microsatellite markers, the tetranucleotide marker D2S1394 was found to be in LD in the 2p13 region. Screening this region with additional microsatellite markers revealed that the adjacent marker D2S1374 was also significantly associated with obstetric cholestasis, whereas no association was found with the markers located in the vicinity of the hydroxyacyl-CoA dehyrogenase/3-ketoacyl-CoA thiolase/enoyl-CoA hydratase, alpha subunit (HADHA) gene. CONCLUSIONS: Collectively, these data suggest that there may be a novel obstetric cholestasis-associated gene located in the vicinity of the 2p13 LD region.