Breast cancer and systemic sclerosis: A clinical description of 21 patients in a population-based cohort study

The original publication can be found at www.springerlink.comPrevious studies have demonstrated an increased risk of breast cancer among patients with systemic sclerosis (scleroderma). To describe the clinical characteristics of 21 patients with both systemic sclerosis and breast cancer, and compare their risk factors to female scleroderma patients without breast cancer, in a population-based cohort study of South Australia. Subjects with scleroderma and breast cancer were identified from the South Australian Scleroderma Register with cross-linking to the South Australian Cancer Registry, last updated to the end of December 2005. Clinical information was obtained from standardised self-administered questionnaires and case note reviews. Odds ratios for the risk factors for breast cancer in scleroderma were determined, and clinical variables were analysed using chi square, Fisher’s exact, Mann–Whitney and t tests. At the end of December 2005 there were a total of 389 female patients with scleroderma. Of these, 21 (5.4%) had been diagnosed with breast cancer. The mean age of onset of scleroderma was 43.5 years, and the mean age of breast cancer was 60.5 years in those with scleroderma and breast cancer. The majority (71.4%) had limited scleroderma, with anti-centromere antibody being the most prevalent serological abnormality. In 16 (76%) patients the diagnosis of breast cancer occurred on an average of 22.3 years after the onset of their first scleroderma symptom. When compared to 48 controls, scleroderma patients with breast cancer were found to have a higher incidence of a positive family history of breast cancer (Fisher’s exact test, p = 0.04) and a lower incidence of hormone-replacement therapy use (Fisher’s exact test, p = 0.0026). This population-based cohort study provides evidence that the majority of patients with scleroderma and breast cancer have limited scleroderma and anti-centromere antibody. Given the increased incidence of solid tumours in systemic sclerosis, we suggest regular screening of female patients for breast cancer, especially in those with a family history.Tim Y. -T. Lu, Catherine L. Hill, Eliza K. Pontifex and Peter J. Roberts-Thomso

Intracellular free radical production by peripheral blood T lymphocytes from patients with systemic sclerosis: Role of NADPH oxidase and ERK1/2

INTRODUCTION: Abnormal oxidative stress has been described in systemic sclerosis (SSc) and previous works from our laboratory demonstrated an increased generation of reactive oxygen species (ROS) by SSc fibroblasts and monocytes. This study investigated the ability of SSc T lymphocytes to produce ROS, the molecular pathway involved, and the biological effects of ROS on SSc phenotype. METHODS: Peripheral blood T lymphocytes were isolated from serum of healthy controls or SSc patients by negative selection with magnetic beads and activated either with PMA or with magnetic beads coated with anti-CD3 and anti-CD28 antibodies. Intracellular ROS generation was measured using a DCFH-DA assay in a plate reader fluorimeter or by FACS analysis. CD69 expression and cytokine production were analyzed by FACS analysis. Protein expression was studied using immunoblotting techniques and mRNA levels were quantified by real-time PCR. Cell proliferation was carried out using a BrdU incorporation assay. RESULTS: Peripheral blood T lymphocytes from SSc patients showed an increased ROS production compared to T cells from healthy subjects. Since NADPH oxidase complex is involved in oxidative stress in SSc and we found high levels of gp91phox in SSc T cells, SSc T cells were incubated with chemical inhibititors or specific siRNAs against gp91phox. Inhibition of NADPH oxidase partially reverted CD69 activation and proliferation rate increase, and significantly influenced cytokine production and ERK1/2 activation. CONCLUSIONS: SSc T lymphocityes are characterized by high levels of ROS, generated by NADPH oxidase via ERK1/2 phosphorylation, that are essential for cell activation, proliferation, and cytokine production. These data confirm lymphocytes as key cellular players in the pathogenesis of systemic sclerosis and suggest a crucial link between ROS and T cell activation. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13075-015-0591-8) contains supplementary material, which is available to authorized users