Higher Bone Density is Associated with a Decreased Risk of Colon Adenomas in Women

Purpose: Bone mass has been proposed as a biomarker of the cumulative exposure to calcium, vitamin D and endogenous and exogenous estrogens. Postmenopausal women with higher levels of bone mass have a decreased risk of colon cancer. No prior studies, however, have examined the role between bone mass and the risk of colon adenomas, which are precursor lesions that, if not removed, may lead to colon cancer.

Methods: We evaluated the potential association between bone mass, as measured by bone mineral density (BMD) using dual-energy X-ray absorptiometry (DXA), and colon adenomas in 167 patients who underwent colonoscopy screening at University Hospitals in Cleveland, Ohio.

Results: We found that women with a total body BMD exceeding 1.294 g/cm2 (third tertile) compared to those with a total body BMD less than 1.167 g/cm2 (first tertile) had a much lower risk of colon adenomas (OR = 0.10; 95% C.I.: 0.02-0.74; P = 0.02). Similarly, women with a total body BMD between 1.167 and 1.294 g/cm2 (second tertile) compared to those with a BMD less than 1.167 g/cm2 had a decreased risk for colon adenomas (OR = 0.15; 95% C.I.: 0.03-0.80; P = 0.03; p-trend = 0.01). Postmenopausal women with a total body BMD in the second and third highest tertiles combined compared to those in the first tertile also had a decreased risk of colon adenomas.

Conclusions: Our results show, for the first time, that bone mass, as measured by total body BMD, is inversely associated with colon adenomas in women, which suggests the mechanisms underlying the synergistic actions of calcium, vitamin D, estrogen exposure and other factors affecting BMD including exercise are key to preventing the development of colonic lesions, particularly among women.

127. PUMA MEDIATES GERM CELL DEATH DURING OVARIAN DEVELOPMENT AND DETERMINES INITIAL PRIMORDIAL FOLLICLE NUMBER IN MICE

The proteins that control the number of primordial follicles initially established within the ovary are largely unknown. Here we investigated the hypothesis that PUMA, a pro-apoptotic protein belonging to the Bcl-2 family, regulates germ cell death during ovarian development and thereby determines the number of primordial follicles that make up the ovarian reserve. Ovaries were obtained from embryonic day 17.5 (E17.5) and post-natal day 10 (PN10) wild-type (wt) and puma–/– mice and subjected to morphological, molecular and stereological characterisation (n = 3-6 mice/genotype/age). At E17.5, ovaries were densely populated with germ cells and early meiotic oocytes. Immunostaining for MVH and PCNA confirmed the identity of germ cells and proliferating germ cells, respectively. Pyknotic nuclei and TUNEL positive germ cells were rarely detected, suggesting that cell death was uncommon at this age. At PN10, primordial follicle assembly was complete for both genotypes, as confirmed morphologically and by immunostaining for oocyte markers GCNA and MSY2. The number of germ cells in E17.5 wt and puma–/– ovaries was comparable (p=0.81, See Table 1). However, PN10 puma–/– ovaries contained significantly more primordial follicles than wt ovaries (P < 0.001, See Table 1), revealing an over-endowment of primordial follicles in the absence of PUMA. These data show that PUMA regulates the developmentally programmed death of germ cells between E17.5 and PN10 in the mouse and thereby determines the number of primordial follicles that make up the initial ovarian reserve. This work was supported by the NHMRC (Program Grants #494802 and #257502, Fellowships JKF (#441101), KJH (#494836), CLS (#406675), AS (#461299)); the Leukemia and Lymphoma Society (New York; SCOR grant#7015), the National Cancer Institute (NIH, US; CA80188 and CA43540) and Victorian Government Infrastructure Funds.

Evaluation of a candidate breast cancer associated SNP in ERCC4 as a risk modifier in BRCA1 and BRCA2 mutation carriers. Results from the Consortium of Investigators of Modifiers of BRCA1/BRCA2 (CIMBA)

Background:

In this study we aimed to evaluate the role of a SNP in intron 1 of the ERCC4 gene (rs744154), previously reported to be associated with a reduced risk of breast cancer in the general population, as a breast cancer risk modifier in BRCA1 and BRCA2 mutation carriers.

Methods:

We have genotyped rs744154 in 9408 BRCA1 and 5632 BRCA2 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA) and assessed its association with breast cancer risk using a retrospective weighted cohort approach.

Results:

We found no evidence of association with breast cancer risk for BRCA1 (per-allele HR: 0.98, 95% CI: 0.93–1.04, P=0.5) or BRCA2 (per-allele HR: 0.97, 95% CI: 0.89–1.06, P=0.5) mutation carriers.

Conclusion:

This SNP is not a significant modifier of breast cancer risk for mutation carriers, though weak associations cannot be ruled out.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

Ethnic variability in human leukocyte antigen-E haplotypes

Human leukocyte antigen-E (HLA-E) is an important nonclassical major histocompatibility complex (MHC) class I (Ib) molecule that acts as the ligand for NKG2A/B/C receptors expressed on natural killer (NK) cells and T cells. Unlike the classical class I molecules, HLA-E is highly conserved in evolution and the biological significance of polymorphism is therefore unclear. Our aim was to investigate the polymorphism in HLA-E gene in three ethnic groups in the UK and to obtain population data relating to any variations observed at this locus. We developed a polymerase chain reaction-sequence-specific primer (PCR-SSP) method for identifying HLA-E single nucleotide polymorphisms (SNPs) in genomic DNA. This was used to investigate the genotype distribution and allele frequency of nine published SNPs in the coding region of HLA-E in 223 Euro-Caucasoid, 60 Afro-Caribbean and 52 Asian healthy individuals. Genotype frequencies were in Hardy-Weinberg equilibrium. No polymorphism was observed for seven previously reported SNPs and these should not be considered polymorphic. However, positions 1114 and 1446 were confirmed as polymorphic and different genotype frequencies were identified at nucleotide position 1114 between the three studied ethnic groups. We present these data together with the intragene haplotype frequencies in these populations. To our knowledge, this is the first description of population frequencies of nine different SNPs in HLA-E in three main large ethnic groups. The data generated from this study will be of importance in the context of describing the effect of HLA-E polymorphism in clinical settings such as transplantation and autoimmune diseases.

Donor HLA-C genotype has a profound impact on the clinical outcome following liver transplantation

Late allograft dysfunction is a significant problem following liver transplantation and its pathogenesis is uncertain. HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that regulate the cytotoxic activity of natural killer (NK) cells. HLA-C alleles can be allocated into two groups, termed HLA-C1 and HLA-C2, based on their KIR specificity. HLA-C2 interactions are more inhibiting to NK cell activation. We studied the clinical importance of HLA-C genotype in a large liver transplant cohort and found that possession of at least one HLA-C2 allele by the donor allograft was associated with less histological evidence of chronic rejection and graft cirrhosis, a 16.2% reduction in graft loss (p = 0.003) (hazard ratio: 2.7, 95% CI 1.4-5.3) and a 13.6% improvement in patient survival (p = 0.01) (hazard ratio: 1.9, 95% CI 1.1-3.3) at 10 years. Transplantation of an HLA-C2 homozygous allograft led to a particularly striking 26.5% reduction in graft loss (p < 0.001) (hazard ratio: 7.2, 95% CI 2.2-23.0) at 10 years when compared to HLA-C1 homozygous allografts. Donor HLA-C genotype is therefore a major determinant of clinical outcome after liver transplantation and reveals the importance of NK cells in chronic rejection and graft cirrhosis. Modulation of HLA-C and KIR interactions represents an important novel approach to promote long-term graft and patient survival.

A family of GFP-like proteins with different spectral properties in lancelet Branchiostoma floridae

Background

Members of the green fluorescent protein (GFP) family share sequence similarity and the 11-stranded β-barrel fold. Fluorescence or bright coloration, observed in many members of this family, is enabled by the intrinsic properties of the polypeptide chain itself, without the requirement for cofactors. Amino acid sequence of fluorescent proteins can be altered by genetic engineering to produce variants with different spectral properties, suitable for direct visualization of molecular and cellular processes. Naturally occurring GFP-like proteins include fluorescent proteins from cnidarians of the Hydrozoa and Anthozoa classes, and from copepods of the Pontellidae family, as well as non-fluorescent proteins from Anthozoa. Recently, an mRNA encoding a fluorescent GFP-like protein AmphiGFP, related to GFP from Pontellidae, has been isolated from the lancelet Branchiostoma floridae, a cephalochordate (Deheyn et al., Biol Bull, 2007 213:95).

Results

We report that the nearly-completely sequenced genome of Branchiostoma floridae encodes at least 12 GFP-like proteins. The evidence for expression of six of these genes can be found in the EST databases. Phylogenetic analysis suggests that a gene encoding a GFP-like protein was present in the common ancestor of Cnidaria and Bilateria. We synthesized and expressed two of the lancelet GFP-like proteins in mammalian cells and in bacteria. One protein, which we called LanFP1, exhibits bright green fluorescence in both systems. The other protein, LanFP2, is identical to AmphiGFP in amino acid sequence and is moderately fluorescent. Live imaging of the adult animals revealed bright green fluorescence at the anterior end and in the basal region of the oral cirri, as well as weaker green signals throughout the body of the animal. In addition, red fluorescence was observed in oral cirri, extending to the tips.

Conclusion

GFP-like proteins may have been present in the primitive Metazoa. Their evolutionary history includes losses in several metazoan lineages and expansion in cephalochordates that resulted in the largest repertoire of GFP-like proteins known thus far in a single organism. Lancelet expresses several of its GFP-like proteins, which appear to have distinct spectral properties and perhaps diverse functions.

Reviewers

This article was reviewed by Shamil Sunyaev, Mikhail Matz (nominated by I. King Jordan) and L. Aravind.

Long-term assessment of oxcarbazepine in a naturalistic setting: a retrospective study

BACKGROUND

New antiepileptics seem to be better tolerated by patients. The retention rate of an antiepileptic would be a useful indicator of its practical usefulness.

AIMS

To assess the long-term outcome of oxcarbazepine (OXC) in a naturalistic setting by determining the retention rate.

METHODS

This is a retrospective study. All epilepsy patients treated with OXC at a tertiary care epilepsy center during a period of 3.5 years were included in this study. Retention rates of OXC at 1 and 3 years were estimated for each cohort group using Kaplan-Meier estimates and corresponding 95% confidence intervals.

RESULTS

A total of 98 patients were studied. OXC was used as monotherapy in 14 (14.3%) and as add-on therapy in 84 (85.7%). The mean daily dose was 947 +/- 492 mg and 60% received < or = 900 mg/day. Using the Kaplan-Meier survival analysis, the retention rates of OXC at 1 and 3 years were estimated to be 0.853 (0.749-0.956) and 0.737 (0.570-0.904), respectively.

CONCLUSIONS

OXC is well tolerated by patients as both monotherapy and add-on therapy.

A statistical framework for consolidating "sibling" probe sets for Affymetrix GeneChip data

Background

Affymetrix GeneChip typically contains multiple probe sets per gene, defined as sibling probe sets in this study. These probe sets may or may not behave similar across treatments. The most appropriate way of consolidating sibling probe sets suitable for analysis is an open problem. We propose the Analysis of Variance (ANOVA) framework to decide which sibling probe sets can be consolidated.

Results

The ANOVA model allows us to separate the sibling probe sets into two types: those behave similarly across treatments and those behave differently across treatments. We found that consolidation of sibling probe sets of the former type results in large increase in the number of differentially expressed genes under various statistical criteria. The approach to selecting sibling probe sets suitable for consolidating is implemented in R language and freely available from .

Conclusion

Our ANOVA analysis of sibling probe sets provides a statistical framework for selecting sibling probe sets for consolidation. Consolidating sibling probe sets by pooling data from each greatly improves the estimates of a gene expression level and results in identification of more biologically relevant genes. Sibling probe sets that do not qualify for consolidation may represent annotation errors or other artifacts, or may correspond to differentially processed transcripts of the same gene that require further analysis.

Outcomes after breast cancer in an ethnically diverse cohort of high-risk patients: Differences in survival based on BRCA1/BRCA2 mutation status

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Background: Most studies of hereditary breast cancer report that BRCA1 associated tumors are characterized by high grade and hormone receptor negativity, while those associated with BRCA2 are more similar to sporadic cases. Several groups have demonstrated that BRCA1 mutations, but not BRCA2 mutations, are associated with reduced survival in women with breast cancer. These studies have primarily included women of European and Ashkenazi Jewish heritage. No study to date has assessed outcomes in an ethnically diverse cohort of high-risk individuals. Methods: High-risk individuals were identified through the University of Chicago Cancer Risk Clinic (UCCRC). Clinicopathologic data was collected on all patients with breast cancer who had undergone genetic testing and consented to inclusion in research protocols. Recurrence-free survival (RFS) and overall survival (OS) for BRCA1, BRCA2 and non-carriers was compared using the log-rank test. Hazard ratios (HR) and 95% Confidence Intervals (95% CI) were calculated from Cox proportional hazard models. Results: 280 patients from 258 families were studied. 67 were BRCA1 mutation positive, 36 were BRCA2 positive and 177 were non-carriers. 65% of patients were non-Hispanic non-Jewish whites, 15% African American, 15% Ashkanazi Jewish, 3% Hispanic and 2% Asian. At a median follow up of 5 years, 40 patients had relapsed and 22 had died. HRs (95% CI) for RFS of the BRCA1 and BRCA2 carriers relative to non-carriers were 1.6 (0.77–3.33) and 1.3 (0.55–3.09) respectively, when adjusted for year at diagnosis. The adjusted HRs (95% CI) for OS for the BRCA1 and BRCA2 carriers relative to non-carriers were 1.82 (0.48–3.02) and 0.67 (0.15–3.04), respectively. Conclusions: In this study of an ethnically diverse cohort of high-risk individuals, BRCA1 mutation carriers had a poorer outcome as compared to those with BRCA2 mutations or those without identifiable mutations in either gene, although this difference was not statistically significant. This observation is consistent with previous studies of women of predominantly Ashkenzi Jewish and European ancestry. This study was funded by the Falk Medical Research Trust, the Breast Cancer Research Foundation and the Entertainment Industry Fund.

No significant financial relationships to disclose.

Tremor/ataxia syndrome and fragile X premutation: Diagnostic caveats

The fragile X-associated tremor/ataxia syndrome (FXTAS) is a newly discovered late-onset neurodegenerative disorder caused by a premutation in the FMR1 X-linked gene. We present examples of a discrepancy between obvious brain changes observed on MRI, and minimal clinical neurological manifestations in three older carriers of this premutation. This discrepancy occurred in three of nine carriers ascertained in an unbiased manner. If the systematic follow-up studies of adult carriers confirm this trend, this will have an impact on early diagnosis of neurological involvement and possible prevention. If MRI changes precede clinical manifestation of FXTAS this may explain the low detection rate of fragile X carriers among patients with neurological syndromes associated with tremor/ataxia.

Bactericidal effects of plasma-generated cluster ions

Air purification by plasma-generated cluster ions (PCIs) relies on a novel technology producing hydrated positive and negative ions. Phenomenological tests have shown strong evidence of lethal effects of the PCIs on various micro-organisms. However, the mechanisms of PCI action are still widely unknown. The aim was thus to test the bactericidal efficacy of PCI technology on common indoor micro-organisms and to explore possible PCI mechanisms of action. According to time/dose-dependent experiments with Staphylococcus, Enterococcus, Micrococcus and Bacillus, the inhibiting effects became apparent within the first few minutes of PCI exposure and led to an irreversible 99.9% destruction within the following 2-8 h of exposure. The destructive effect of the PCIs corresponded to membrane damage of the bacteria. Use of the techniques of both SDS PAGE and 2D PAGE revealed changes in the bacterial surface protein composition induced by the PCIs. In contrast, neither DNA nor cytoplasm protein damage was detected electrophoretically. The antimicrobial action of the PCIs seems to occur because of chemical modification of the surface proteins of bacteria. In situ hydroxyl radical formation on the surface of bacteria was proposed as the leading mechanism of the protein damage caused by the PCIs. At the same time, DNA damage seems not to be involved in the antibacterial action of the PCIs. The data obtained would broaden the knowledge concerning the antibacterial effects of air-born plasma-generated cluster ions and help to produce more efficient air-cleaning devices.

Eleven-year survival from an intra-dermal melanoma

Stage IV metastatic malignant melanoma of unknown primary (TxNxM1a) is known to have a poor prognosis. However, some patients suffering from cutaneous disease originally thought to represent metastasis have fared much better than expected. We report a patient who has survived 11 years following such a diagnosis. Due to the prolonged survival and absence of an identified primary, it is unlikely that the lesion was metastatic but may represent one of a number of other possibilities. A small number of similar cases in the literature suggest a need for awareness of this unusual group of patients.

Effect of milking frequency and diet on milk production, energy balance, and reproduction in dairy cows

The objective of this study was to determine the effects of reduced milking frequency and increased dietary energy density in early lactation on milk production, energy balance, and subsequent fertility. Sixty-six spring-calving, multiparous Holstein-Friesian cows were assigned to 1 of 3 treatment groups: once-daily milking on a standard diet (1xST); 3-times daily milking on a standard diet (3xST); and 3-times daily milking on a high-energy diet. Treatments were imposed for the first 28 d of lactation, after which all groups were milked twice daily and fed the standard diet. During the treatment period, the 1xST cows had 19.6% lower milk yield and higher milk fat and milk protein concentrations (15.7 and 10.2%, respectively) compared with 3xST. Dry matter (DM) intake was similar between 1xST and 3xST during the treatment period (12.64 vs. 13.25 kg/ d; SED = 0.82). Daily energy balance was less negative for 1xST compared with 3xST during wk 1 to 3 of lactation [-3.92 vs. -5.30 unité fourragère lait (UFL)/d; SED = 0.65; 1 UFL is equal to the net energy for lactation of 1 kg of standard air-dry barley]. During the treatment period, the cows on the high-energy diet had 17% higher milk yield, higher DM intake (15.5 vs. 13.9 kg/d; SED = 0.71), and similar energy balance (-4.45 vs. -4.35 UFL/d; SED = 0.65) compared to 3xST. Diet had no significant effect on any of the fertility variables measured. The interval to first ovulation was shorter for 1xST than 3xST (18.3d vs. 28.6d; SED = 1.76). In conclusion, once-daily milking in early lactation may promote earlier resumption of ovarian cyclicity, mediated through improved nutritional status.

Increased acute GvHD and higher transplant-related mortality in non-caucasians undergoing standard sibling allogeneic stem cell transplantation

We conducted a retrospective study to compare outcome in Caucasians and non-Caucasians undergoing standard sibling allogeneic SCT. End points of the study were to compare graft-versus-host disease (GvHD) occurrence and transplant-related mortality (TRM). There were 251 patients, 43 non-Caucasian and 208 Caucasian. A higher proportion of non-Caucasian patients developed acute GvHD (aGvHD) grade 2 or greater as compared to the Caucasian group (48 vs 26%, respectively) P = 0.02. With a median follow-up of 27 months, 26% (11/43) of non-Caucasians and 14% (29/208) of Caucasian patients had died from TRM, which accounted for 55% of all deaths in the non-Caucasian group compared to 33% in Caucasians, P = 0.02. Overall survival 12 months post transplant was 64 vs 69% in the non-Caucasian and Caucasian groups, respectively (P = 0.43). Although there were higher numbers of CMV-positive patients in the non-Caucasian group, there were no deaths from CMV reactivation in this subgroup. We conclude that there is increased TRM and aGvHD following standard sibling allograft in the non-Caucasian population and this could be due to either differences in tumour biology or extrinsic factors such as socio-economic factors, nutritional status, post transplant care or presenting with late stage disease.