Expression of prostate-specific antigen (PSA) correlates with poor response to tamoxifen therapy in recurrent breast cancer

Prostate-specific antigen (PSA) is a serine protease which may play a role in a variety of cancer types, including breast cancer. In the present study, we evaluated whether the level of PSA in breast tumour cytosol could be associated with prognosis in primary breast cancer, or with response to tamoxifen therapy in recurrent disease. PSA levels were determined by enzyme-linked immunosorbent assay (ELISA) in breast tumour cytosols, and were correlated with prognosis in 1516 patients with primary breast cancer and with response to first-line tamoxifen therapy in 434 patients with recurrent disease. Relating the levels of PSA with classical prognostic factors, low levels were more often found in larger tumours, tumours of older and post-menopausal patients, and in steroid hormone receptor-negative tumours. There was no significant association between the levels of PSA with grade of differentiation or the number of involved lymph nodes. In patients with primary breast cancer, PSA was not significantly related to the rate of relapse, and a positive association of PSA with an improved survival could be attributed to its relationship to age. In patients with recurrent breast cancer, a high level of PSA was significantly related to a poor response to tamoxifen therapy, and a short progression-free and overall survival after start of treatment for recurrent disease. In Cox multivariate analyses for response to therapy and for (progression-free) survival, corrected for age/menopausal status, disease-free interval, site of relapse and steroid hormone receptor status, PSA was an independent variable of poor prognosis. It is concluded that the level of PSA in cytosols of primary breast tumours might be a marker to select breast cancer patients who may benefit from systemic tamoxifen therapy. © 1999 Cancer Research Campaig

Racism as a determinant of health: a systematic review and meta-analysis

Despite a growing body of epidemiological evidence in recent years documenting the health impacts of racism, the cumulative evidence base has yet to be synthesized in a comprehensive meta-analysis focused specifically on racism as a determinant of health. This meta-analysis reviewed the literature focusing on the relationship between reported racism and mental and physical health outcomes. Data from 293 studies reported in 333 articles published between 1983 and 2013, and conducted predominately in the U.S., were analysed using random effects models and mean weighted effect sizes. Racism was associated with poorer mental health (negative mental health: r = -.23, 95% CI [-.24,-.21], k = 227; positive mental health: r = -.13, 95% CI [-.16,-.10], k = 113), including depression, anxiety, psychological stress and various other outcomes. Racism was also associated with poorer general health (r = -.13 (95% CI [-.18,-.09], k = 30), and poorer physical health (r = -.09, 95% CI [-.12,-.06], k = 50). Moderation effects were found for some outcomes with regard to study and exposure characteristics. Effect sizes of racism on mental health were stronger in cross-sectional compared with longitudinal data and in non-representative samples compared with representative samples. Age, sex, birthplace and education level did not moderate the effects of racism on health. Ethnicity significantly moderated the effect of racism on negative mental health and physical health: the association between racism and negative mental health was significantly stronger for Asian American and Latino(a) American participants compared with African American participants, and the association between racism and physical health was significantly stronger for Latino(a) American participants compared with African American participants.<br /

Parents, predators, parasites, and the evolution of eggshell colour in open nesting birds

The colourful surface of birds’ eggshells varies dramatically between species, but the selective pressures driving this variation remain poorly understood. We used a large comparative dataset to test several hypotheses proposed to explain the evolution of eggshell colouration. We tested the hypothesis that predation pressure might select for cryptic eggshells by examining the relationship between predation rate and egg colouration. We found that predation rates were positively related to eggshell brightness. The blackmail hypothesis suggests that females lay colourful eggshells to coerce males into providing additional care during incubation to keep colourful eggs covered. According to this hypothesis, conspicuous eggs should be found in situations with high risk of visual detection from predators or brood parasites. In support of this hypothesis, proportional blue-green chroma was positively related to parasitism risk, and eggs with higher proportional blue-green chroma or higher ultraviolet chroma received higher combined parental nest attendance during the incubation period. The sexual signalling hypothesis states that blue-green colour indicates female quality; however, we did not find that blue-green eggshell colour was greater in species where males participate in any form of parental care, and relative male provisioning was unrelated to blue-green eggshell chroma. We found some support for the hypothesis that brood parasitism may select for high inter-clutch variation in eggshell colour to facilitate egg recognition. In our dataset, parasitism risk was negatively related to inter-clutch repeatability of blue-green chroma. Our study highlights the diversity of selection pressures acting on the evolution of eggshell colour in birds and provides suggestions for novel areas of future key research direction.Daniel Hanley, Phillip Cassey, Stéphanie M. Douce