Public health genomics and personalized prevention: lessons from the COGS project

Using the principles of public health genomics, we examined the opportunities and challenges of implementing personalized prevention programmes for cancer at the population level. Our model-based estimates indicate that polygenic risk stratification can potentially improve the effectiveness and cost-effectiveness of screening programmes. However, compared with 'one-size-fits-all' screening programmes, personalized screening adds further layers of complexity to the organization of screening services and raises ethical, legal and social challenges. Before polygenic inheritance is translated into population screening strategy, evidence from empirical research and engagement with and education of the public and the health professionals are needed.

Phonological and articulation treatment approaches in Portuguese children with speech and language impairments: a randomized controlled intervention study

BACKGROUND

In Portugal, the routine clinical practice of speech and language therapists (SLTs) in treating children with all types of speech sound disorder (SSD) continues to be articulation therapy (AT). There is limited use of phonological therapy (PT) or phonological awareness training in Portugal. Additionally, at an international level there is a focus on collecting information on and differentiating between the effectiveness of PT and AT for children with different types of phonologically based SSD, as well as on the role of phonological awareness in remediating SSD. It is important to collect more evidence for the most effective and efficient type of intervention approach for different SSDs and for these data to be collected from diverse linguistic and cultural perspectives.

AIMS

To evaluate the effectiveness of a PT and AT approach for treatment of 14 Portuguese children, aged 4.0-6.7 years, with a phonologically based SSD.

METHODS & PROCEDURES

The children were randomly assigned to one of the two treatment approaches (seven children in each group). All children were treated by the same SLT, blind to the aims of the study, over three blocks of a total of 25 weekly sessions of intervention. Outcome measures of phonological ability (percentage of consonants correct (PCC), percentage occurrence of different phonological processes and phonetic inventory) were taken before and after intervention. A qualitative assessment of intervention effectiveness from the perspective of the parents of participants was included.

OUTCOMES & RESULTS

Both treatments were effective in improving the participants' speech, with the children receiving PT showing a more significant improvement in PCC score than those receiving the AT. Children in the PT group also showed greater generalization to untreated words than those receiving AT. Parents reported both intervention approaches to be as effective in improving their children's speech.

CONCLUSIONS & IMPLICATIONS

The PT (combination of expressive phonological tasks, phonological awareness, listening and discrimination activities) proved to be an effective integrated method of improving phonological SSD in children. These findings provide some evidence for Portuguese SLTs to employ PT with children with phonologically based SSD.

Macroparasites at peripheral sites of infection are major and dynamic modifiers of systemic antimicrobial pattern recognition responses

Immune defences and the maintenance of immunological homeostasis in the face of pathogenic and commensal microbial exposures are channelled by innate antimicrobial pattern recognition receptors (PRRs) such as toll-like receptors (TLRs). Whilst PRR-mediated response programmes are the result of long-term host-pathogen or host-commensal co-evolutionary dynamics involving microbes, an additional possibility is that macroparasitic co-infections may be a significant modifier of such interactions. We demonstrate experimentally that macroparasites (the model gastrointestinal nematode, Heligmosomoides) at peripheral sites of infection cause substantial alteration of the expression and function of TLRs at a systemic level (in cultured splenocytes), predominantly up-regulating TLR2, TLR4 and TLR9-mediated cytokine responses at times of high standing worm burdens. We consistently observed such effects in BALB/c and C57BL/6 mice under single-pulse and trickle exposures to Heligmosomoides larvae and in SWR and CBA mice under single-pulse exposures. A complementary long-term survey of TLR2-mediated tumour necrosis factor-alpha responses in wild wood mice (Apodemus sylvaticus) was consistent with substantial effects of macroparasites under some environmental conditions. A general pattern, though, was for the associations of macroparasites with TLR function to be temporally dynamic and context-dependent: varying with different conditions of infection exposure in the field and laboratory and with host genetic strain in the laboratory. These results are compelling evidence that macroparasites are a major and dynamic modifier of systemic innate antimicrobial responsiveness in naturally occurring mammals and thus likely to be an important influence on the interaction between microbial exposures and the immune system.

Stratified cancer screening: the practicalities of implementation

BACKGROUND

Improving understanding of the genetic basis of disease susceptibility enables us to estimate individuals' risk of developing cancer and offer them disease prevention, including screening, stratified to reflect that risk. Little attention has so far been given to the implementation of stratified screening. This article reviews the issues that would arise in delivering such tailored approaches to prevention in practice.

RESULTS

Issues analysed include the organisational context within which implementation of stratified prevention would occur, how the offer of screening would be made, making sure consent is adequately informed, how individuals' risk would be assessed, the age at which risk estimation should occur, and the potential use of genetic data for other purposes. The review also considers how management might differ depending on individuals' risk, how their results would be communicated and their follow-up arranged, and the different issues raised by modification of an existing screening programme, such as that for breast cancer, and the establishment of a new one, for example for prostate cancer.

CONCLUSION

Stratified screening based on genetic testing is a radically new approach to prevention. Various organisational issues would need to be considered before it could be introduced, and a number of questions require further research.

A tumor suppressor role for srGAP3 in mammary epithelial cells

srGAP3, a member of the Slit-Robo sub-family of Rho GTPase-activating proteins (Rho GAPs), controls actin and microtubule dynamics through negative regulation of Rac. Here, we describe a potential role for srGAP3 as a tumor suppressor in mammary epithelial cells. We show that RNAi-mediated depletion of srGAP3 promotes Rac dependent, anchorage-independent growth of partially transformed human mammary epithelial cells (HMECs). Furthermore, srGAP3 expression is absent, or significantly reduced in 7/10 breast cancer cell lines compared with normal HMECs. Re-expression of srGAP3 in a subset of these cell lines inhibits both anchorage-independent growth and cell invasion in a GAP-dependent manner, and this is accompanied by an increase in phosphorylation of the ezrin/radixin/moesin (ERM) family proteins and myosin light chain 2 (MLC2). Inhibition of the Rho regulated kinase, ROCK, reduces ERM and MLC2 phosphorylation and restores invasion. We conclude that srGAP3 has tumor suppressor-like activity in HMECs, likely through its activity as a negative regulator of Rac1.

The anthropometric status of elderly women in rural Ghana and factors associated with low body mass index

OBJECTIVES

To describe the anthropometric and physical status of a sample of elderly women in rural Ghana and examine factors associated with a low body mass index (BMI).

DESIGN

A cross-sectional survey.

SETTING

Two rural villages in Ashanti Region, Ghana.

PARTICIPANTS

Fifty-nine elderly women aged 60 to 92 years.

MEASUREMENTS

The weight, height, half armspan and mid-upper arm circumference (MUAC) of each woman was measured; body mass index (BMI) and body mass for armspan (BMA) were calculated. The state of each woman's teeth and visual acuity was assessed. Data on food security, eating habits and socio-economic status were collected by questionnaire.

RESULTS

41% (95%CI 27.8, 53.6) of women were underweight and 16.9% (95%CI 7.18, 26.8) were overweight or obese. Factors associated with a low BMI (<18.5 kg/m2) were: age (P=0.001), chewing tobacco (P=0.002), drinking alcohol (P=0.012), a visual acuity score of <30% (P=0.038), using a walking aid (P=0.016) and the number of children who gave the women cash (P=0.005). BMI was strongly positively correlated with BMA (r=0.999, P<0.001) and with MUAC (r=0.91, P<0.001), and a BMI of 18.5 was equivalent to a MUAC of about 23cm.

CONCLUSION

Elderly women in Ghana with poor teeth and eyesight are at risk of undernutrition. Measurements of MUAC, which is simple, or BMA, which is based on weight and half armspan and is more easily measured and calculated than height and BMI, could be used to identify undernourished elderly women in rural Africa.

Germline BRCA1 mutations increase prostate cancer risk

BACKGROUND

Prostate cancer (PrCa) is one of the most common cancers affecting men but its aetiology is poorly understood. Family history of PrCa, particularly at a young age, is a strong risk factor. There have been previous reports of increased PrCa risk in male BRCA1 mutation carriers in female breast cancer families, but there is a controversy as to whether this risk is substantiated. We sought to evaluate the role of germline BRCA1 mutations in PrCa predisposition by performing a candidate gene study in a large UK population sample set.

METHODS

We screened 913 cases aged 36–86 years for germline BRCA1 mutation, with the study enriched for cases with an early age of onset. We analysed the entire coding region of the BRCA1 gene using Sanger sequencing. Multiplex ligation-dependent probe amplification was also used to assess the frequency of large rearrangements in 460 cases.

RESULTS

We identified 4 deleterious mutations and 45 unclassified variants (UV). The frequency of deleterious BRCA1 mutation in this study is 0.45%; three of the mutation carriers were affected at age 65 years and one developed PrCa at 69 years. Using previously estimated population carrier frequencies, deleterious BRCA1 mutations confer a relative risk of PrCa of ~3.75-fold, (95% confidence interval 1.02–9.6) translating to a 8.6% cumulative risk by age 65.

CONCLUSION

This study shows evidence for an increased risk of PrCa in men who harbour germline mutations in BRCA1. This could have a significant impact on possible screening strategies and targeted treatments.