Subtypes DNA methylation MOMA Survival Epigenetics A B S T R A C TThe diversity of breast cancers reflects variations in underlying biology and affects the clinical implications for patients. Gene expression studies have identified five major subtypese Luminal A, Luminal B, basal-like, ErbB2þ and Normal-Like. We set out to determine the role of DNA methylation in subtypes by performing genome-wide scans of CpG methylation in breast cancer samples with known expression-based subtypes. Unsupervised hierarchical clustering using a set of most varying loci clustered the tumors into a Luminal A majority (82%) cluster, Basal-like/ErbB2þ majority (86%) cluster and a non-specific cluster with samples that were also inconclusive in their expression-based subtype correlations.Contributing methylation loci were both gene associated loci (30%) and non-gene associ-

Keratinocytes respond to injury by releasing the proinflammatory cytokine interleukin-1, which serves as the initial "alarm signal" to surrounding cells. Among the consequences of interleukin-1 release is the production of additional cytokines and their receptors by keratinocytes and other cells in the skin. Here we describe an additional effect of interleukin-1 on keratinocytes, namely the alteration in the keratinocyte cytoskeleton in the form of the induction of keratin 6 expression. Keratin 6 is a marker of hyperproliferative, activated keratinocytes, found in wound healing, psoriasis, and other inflammatory disorders. Skin biopsies in organ culture treated with interleukin-1 express keratin 6 in all suprabasal layers of the epidermis, throughout the tissue. In cultured epidermal keratinocytes, the induction of keratin 6 is time and concentration dependent. Importantly, only confluent keratinocytes respond to interleukin-1, subconfluent cultures do not. In the cells starved of growth factors, epidermal growth factor or tumor necrosis factor-alpha, if added simultaneously with interleukin-1, they synergistically augment the effects of interleukin-1. Using DNA-mediated cell transfection, we analyzed the molecular mechanisms regulating the keratin 6 induction by interleukin-1, and found that the induction occurs at the transcriptional level. We used a series of deletions and point mutations to identify the interleukin-1 responsive DNA element in the keratin 6 promoter, and determined that it contains a complex of C/EBP binding sites. The transcription factor C/EBPbeta binds this element in vitro, and the binding is augmented by pretreatment of the cells with interleukin-1. The interleukin-1 responsive element is clearly distinct from the epidermal growth factor responsive one, which means that the proinflammatory and proliferative signals independently regulate the expression of keratin 6. Thus, interleukin-1 initiates keratinocyte activation not only by triggering additional signaling events, but also by inducing directly the synthesis of keratin 6 in epidermal keratinocytes, and thus changing the composition of their cytoskeleton.

Postnatal lung growth and development has primarily been evaluated from a very limited number of autopsied lungs; however, it still remains unclear whether alveolarization of the lung is complete during infancy and whether the conducting airways grow proportionately. The purpose of our study was to evaluate lung growth and development in vivo in infants and toddlers using multi-slice computed tomography. Thirty-eight subjects (14 male, 24 female) aged 24–142 weeks had low-dose volumetric HRCT imaging at an inflation pressure of 20 cmH2O during an induced respiratory pause. Lung volume and weight were determined, as well as airway dimensions (inner and outer area, and wall area) for the trachea and next 3–4 generations. Lung volume, air volume, and tissue volume increased linearly with body length. The air and tissue components of the lung parenchyma increased at a constant rate with each other. In addition, airway caliber decreased with increasing generation from the trachea into each lobe. Airway caliber also correlated with body length; however, there was no interaction effect between airway generation and body length on transformed airway size. Our in vivo assessment suggests that growth of the lung parenchyma in infants and toddlers occurred with a constant relationship between air volume and lung tissue, which is consistent with lung growth occurring primarily by the addition of alveoli, rather than expansion of alveoli. In addition, the central conducting airways grow proportionately in infants and toddlers. This information may be important for evaluating subjects with arrested lung development.