Assessing interactions between the associations of common genetic susceptibility variants, reproductive history and body mass index with breast cancer risk in the breast cancer association consortium: a combined case-control study

Introduction

Several common breast cancer genetic susceptibility variants have recently been identified. We aimed to determine how these variants combine with a subset of other known risk factors to influence breast cancer risk in white women of European ancestry using case-control studies participating in the Breast Cancer Association Consortium.

Methods

We evaluated two-way interactions between each of age at menarche, ever having had a live birth, number of live births, age at first birth and body mass index (BMI) and each of 12 single nucleotide polymorphisms (SNPs) (10q26-rs2981582 (FGFR2), 8q24-rs13281615, 11p15-rs3817198 (LSP1), 5q11-rs889312 (MAP3K1), 16q12-rs3803662 (TOX3), 2q35-rs13387042, 5p12-rs10941679 (MRPS30), 17q23-rs6504950 (COX11), 3p24-rs4973768 (SLC4A7), CASP8-rs17468277, TGFB1-rs1982073 and ESR1-rs3020314). Interactions were tested for by fitting logistic regression models including per-allele and linear trend main effects for SNPs and risk factors, respectively, and single-parameter interaction terms for linear departure from independent multiplicative effects.

Results

These analyses were applied to data for up to 26,349 invasive breast cancer cases and up to 32,208 controls from 21 case-control studies. No statistical evidence of interaction was observed beyond that expected by chance. Analyses were repeated using data from 11 population-based studies, and results were very similar.

Conclusions

The relative risks for breast cancer associated with the common susceptibility variants identified to date do not appear to vary across women with different reproductive histories or body mass index (BMI). The assumption of multiplicative combined effects for these established genetic and other risk factors in risk prediction models appears justified.     

Hyaluronan in human tumors: pathobiological and prognostic messages from cell-associated and stromal hyaluronan

Cancers are supported by a distinct type of connective tissue stroma, crucial for tumor survival and advancement. Hyaluronan is a major matrix molecule in the stroma of many common tumors, and involved in their growth and spreading. Here we focus in recent data on stromal hyaluronan in human tumors, and that on the surface of the malignant cells. Hyaluronan accumulation is most conspicuous in malignancies that develop in cells and tissues normally devoid of hyaluronan, such as single layered epithelia and their hyaluronan-poor connective tissue stroma. The magnitude of the hyaluronan accumulation in the malignant epithelium itself (e.g. colon and gastric cancers) or tumor stroma (breast, ovarian, prostate cancers) strongly correlates with an unfavorable prognosis of the patient, i.e. advancement of the malignancy. A completely different pattern arises from stratified epithelia that normally produce hyaluronan and are surrounded by a hyaluronan-rich stroma. The cell surface of the latter group of tumors (e.g. squamous cell carcinomas of skin, mouth, larynx and esophagus, and skin melanoma) show abundant hyaluronan which tends to get reduced and patchy in the most advanced stages of the tumors, suggesting enhanced turnover. While the assays of human tumors represent snapshots of currently unknown processes and kinetics of hyaluronan metabolism, it is obvious that hyaluronan accumulation at some stage is an inherent feature in most of the common epithelial malignant tumors. The possible contributions of inflammatory cells, stem cells, mutated stromal cells, or otherwise deranged growth factor exchange between stromal and cancer cells are discussed as possible explanations to hyaluronan abundance in the tumors. The importance of hyaluronan in human tumor progression will be further clarified when drugs become available to modify hyaluronan metabolism.     

Angiographically guided utero-placental gene transfer in rabbits with adenoviruses, plasmid/liposomes and plasmid/polyethyleneimine complexes.

We examined the feasibility of gene transfer to rabbit placenta using adenoviruses, plasmid/liposomes and plasmid/polyethyleneimine (PEI) complexes. Pregnant New Zealand White rabbits (n = 17) were anesthetized and local gene transfer was done via a catheter inserted in uterine arteries under direct angiographic control. Either nuclear targeted LacZ adenoviruses (1.0 x 10(10) p.f.u.), nuclear targeted LacZ plasmid (500 microg)/liposome (DOTMA:DOPE 1:1) complexes or nuclear targeted LacZ plasmid (250 microg)/PEI (25 kDa) complexes (charge ratio +/-4) were used. Animals were killed 3 days later and detection of the transgene expression was done by X-gal staining and RT-PCR. Adenovirus-mediated gene transfer resulted in a high transfection efficiency (34 +/- 10%) in placental trophoplastic cells. Very little, if any, transfection was seen in fetal membranes. Plasmid/liposomes and plasmid/PEI complexes led to a very low (<0.01%) transfection efficiency in trophoblastic cells, but some transfection was seen in fetal membranes. A total of 25 fetuses were analyzed for the presence of transgene at the time of death. In most fetuses expression of the LacZ gene was below the sensitivity of the X-gal staining, but expression was detected by PCR in 50%, 50% and 42% of the analyzed fetuses after adenoviral, plasmid/PEI and plasmid/liposome gene transfer, respectively. No major inflammatory changes were present in the transfected placentas as analyzed by general histology and macrophage- and T cell-specific immunostainings. We conclude that catheter-mediated intravascular gene transfer with adenoviruses can be used for the transfection of placental trophoplastic cells, but plasmid complexes are inefficient for this purpose. However, selective angiographically guided gene transfer also led to leakage of the vector to fetuses. Therefore, if gene therapy is developed for the treatment of placental disorders, the gene-vector combination should not be harmful to the fetus and the expression of the transgene should only occur in placenta.     

Isoform-specific regulation of the actin-organizing protein palladin during TGF-beta1-induced myofibroblast differentiation

Contractile myofibroblasts are responsible for remodeling of extracellular matrix during wound healing; however, their continued activity results in various fibrocontractive diseases. Conversion of fibroblasts into myofibroblasts is induced by transforming growth factor-beta1 (TGF-beta1) and is hallmarked by the neo-expression of alpha-smooth muscle actin (alpha-SMA), a commonly used myofibroblast marker. Moreover, myofibroblast differentiation and acquisition of the contractile phenotype involves functionally important alterations in the expression of actin-organizing proteins. We investigated whether myofibroblast differentiation is accompanied by changes in the expression of palladin, a cytoskeletal protein that controls stress fiber integrity. Palladin is expressed as several isoforms, including major 3Ig (90 kDa) and 4Ig (140 kDa) forms that differ in their N-terminal sequence. Expression of the 4Ig isoform is strongly induced in fibroblast stress fibers upon TGF-beta1 treatment preceding alpha-SMA upregulation. TGF-beta1 induced upregulation of palladin is mediated both by Smad and mitogen-activated protein kinase pathways. Furthermore, palladin 4Ig-isoform is co-expressed with alpha-SMA in vivo in experimental rat wounds and in human myofibroblast-containing lesions. Taken together these results identify palladin 4Ig as a novel marker of myofibroblast conversion in vitro and in vivo. They also provide for the first time information about the signaling cascades involved in the regulation of palladin expression.     

Expression of CD44 standard and variant-v6 proteins in transitional cell bladder tumours and their relation to prognosis during a long-term follow-up

The expression of the standard CD44 (CD44s) and its v6 isoform (CD44v6) was analysed immunohistochemically in 173 cases of transitional cell bladder cancer. The results of immunohistochemical analyses were related to established prognostic factors and clinical follow-up data. The expression intensity of CD44s in non-basal tumour cells was significantly related to TN classification, S-phase fraction (SPF), mitotic index, grade, density of tumour infiltrating lymphocytes. The expression intensity of CD44v6 in non-basal tumour cells was inversely related to DNA ploidy, SPF, and mitotic index. The expression intensity of CD44v6 in basal tumour cells was also inversely related to T-category, grade, papillary status, DNA ploidy, SPF, and mitotic index. Strong expression of CD44s in non-basal tumour cells was related to unfavourable outcome in univariate analysis (p=0·008), whereas the strong expression of CD44v6 in both non-basal cells (p=0·005) and basal cells (p=0·0008) was related to high survival probability. In multivariate survival analysis, the expression intensity of CD44v6 was independently related to favourable outcome in muscle invasive tumours, while in superficial tumours, CD44s was an independent prognostic factor. The results suggest that the expression of CD44s and CD44v6 is associated with malignant features and prognosis in bladder cancer. Copyright © 1998 John Wiley & Sons, Ltd.     

A Comparison of Two Measures of Physical Activity Among Adults with Physical Disabilities: The Issue of Scale Correspondence

The purpose of the study was to examine the issue of scale correspondence by testing the theory of planned behavior (TPB) using two models. Participants were 223 adults (M age = 45.4 years, SD = 10.8) with self-reported physical disabilities who completed an on-line survey. Using a cross-sectional design, participants completed demographic questions, TPB items, and two measures of physical activity. Path analyses, using one model that included a measure of behavior developed according to the TPB recommendations and a second model that used the Physical Activity Scale for Individuals with Physical Disabilities (PASIPD) generally supported the hypotheses of the TPB. Further, the model with the TPB scale (R ² = .66) accounted for more variance in physical activity than the model using the PASIPD (R ² = .15). Our findings are consistent with previous research; however, we argue that scale correspondence may not be statistically or philosophically appropriate.     

Antiangiogenic Gene Therapy With Soluble VEGFR-1, -2, and -3 Reduces the Growth of Solid Human Ovarian Carcinoma in Mice

We studied antiangiogenic and antilymphangiogenic effects of sVEGFR-1 (sFlt-1), sVEGFR-2 (sFlk-1/KDR), and sVEGFR-3 (sFlt-4) gene transfers and their combinations in intraperitoneal ovarian cancer xenograft mice (Balb/c-Anu, n = 55). Gene therapy was initiated when the presence of sizable tumors was confirmed in magnetic resonance imaging (MRI). Adenovirus-mediated gene transfer was performed intravenously via tail vein as follows: AdLacZ as a control (group I), AdsFlt-1 (group II), AdsKDR (group III), AdsFlt-4 (group IV) and two combination groups of AdsFlt-1 and AdsFlt-4 (group V) and AdsFlt-1, AdsKDR, and AdsFlt-4 (group VI). Antitumor effectiveness was assessed by sequential MRI, immunohistochemistry, microvessel density, overall tumor growth, and survival time. In combination group VI, intraperitoneal tumors were significantly smaller than in the control group at the end of the follow-up (P < 0.001). Furthermore, in group VI the microvessel density (microvessels/mm²) in tumor tissue and the total area of tumors covered by microvessels were significantly smaller than in the controls. One mouse in group V was cured. The combined antiangiogenic gene therapy with soluble VEGFRs reduced tumor growth, tumor vascularity, and ascites formation in ovarian cancer xenografts. The results suggest that the combined antiangiogenic gene therapy is a potential approach for the treatment of ovarian cancer patients.     

Evaluation of a di‐O‐methylated glycan as a potential antigenic target for the serodiagnosis of human toxocariasis

Serodiagnosis of human toxocariasis is based on the detection of specific IgG antibodies by the enzyme‐linked immunosorbent assay (ELISA) using Toxocara larvae excretory–secretory (TES) antigens, but its production is a laborious and time‐consuming process being also limited by the availability of adult females of T. canis as source for ova to obtain larvae. Chemical synthesis of the di‐O‐methylated (DiM) glycan structure found in the TES antigens has provided material for studying the antibody reactivity in a range of mammalian hosts, showing reactivity with human IgM and IgG. In this study, we have evaluated the performance of the DiM glycan against a panel of sera including patients with toxocariasis (n = 60), patients with other helminth infections (n = 75) and healthy individuals (n = 94), showing that DiM is able to detect IgG antibodies with a sensitivity and specificity of 91·7% and 94·7%, respectively, with a very good agreement with the TES antigens (kappa = 0·825). However, cross‐reactivity was observed in some sera from patients with ascariasis, hymenolepiasis and fascioliasis. These results show that the DiM glycan could be a promising antigenic tool for the serodiagnosis of human toxocariasis.     

No harm from five year ingestion of oats in coeliac disease

BACKGROUND: Six to 12 months of ingestion of moderate amounts of oats does not have a harmful effect in adult patients with coeliac disease. As the safety of long term intake of oats in coeliac patients is not known, we continued our previous 6-12 month study for five years. AIM: To assess the safety of long term ingestion of oats in the diet of coeliac patients. PATIENTS: In our previous study, the effects of a gluten free diet and a gluten free diet including oats were compared in a randomised trial involving 92 adult patients with coeliac disease (45 in the oats group, 47 in the control group). After the initial phase of 6-12 months, patients in the oats group were allowed to eat oats freely in conjunction with an otherwise gluten free diet. After five years, 35 patients in the original oats group (23 still on an oats diet) and 28 in the control group on a conventional gluten free diet were examined. METHODS: Clinical and nutritional assessment, duodenal biopsies for conventional histopathology and histomorphometry, and measurement of antiendomysial, antireticulin, and antigliadin antibodies. RESULTS: There were no significant differences between controls and those patients consuming oats with respect to duodenal villous architecture, inflammatory cell infiltration of the duodenal mucosa, or antibody titres after five years of follow up. In both groups histological and histomorphometric indexes improved equally with time. CONCLUSIONS: This study provides the first evidence of the long term safety of oats as part of a coeliac diet in adult patients with coeliac disease. It also appears that the majority of coeliac patients prefer oats in their diet.