The development of breast cancer is linked to the loss of estrogen receptor (ER) during the course of tumor progression, resulting in loss of responsiveness to hormonal treatment. The mechanisms underlying dynamic ERα gene expression change in breast cancer remain unclear. A range of physiological and biological changes, including increased adipose tissue hypoxia, accompanies obesity. Hypoxia in adipocytes can establish a pro-malignancy environment in breast tissues. Epidemiological studies have linked obesity with basal-like breast cancer risk and poor disease outcome, suggesting that obesity may affect the tumor phenotype by skewing the microenvironment toward support of more aggressive tumor phenotypes. In the present study, human SGBS adipocytes were co-cultured with ER-positive MCF7 cells for 24 h. After co-culture, HIF1α, TGF-β, and lectin-type oxidized LDL receptor 1 (LOX1) mRNA levels in the SGBS cells were increased. Expression levels of the epithelial-mesenchymal transition (EMT)-inducing transcription factors FOXC2 and TWIST1 were increased in the co-cultured MCF7 cells. In addition, the E-cadherin mRNA level was decreased, while the N-cadherin mRNA level was increased in the co-cultured MCF7 cells. ERα mRNA levels were significantly repressed in the co-cultured MCF7 cells. ERα gene expression in the MCF7 cells was decreased due to increased HIF1α in the SGBS cells. These results suggest that adipocytes can modify breast cancer cell ER gene expression through hypoxia and also can promote EMT processes in breast cancer cells, supporting an important role of obesity in aggressive breast cancer development.

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Pediatric cataract of the congenital type is the most common form of childhood blindness and it is clinically and genetically heterogeneous. Mutations in 22 different genes have been identified to be associated with congenital cataracts, and among them, eight mutants belong to αA-crystallin. To explain how mutations in αA-crystallin lead to the development of cataract, quaternary structural parameters, and chaperone function have been investigated in αA-wt and in the following mutants: R12C, R21L, R21W, R49C, R54C, R116C, and R116H. Average molar mass, mass at the RI peak, mass across the peak, hydrodynamic radius (Rh), and polydispersity index (PDI) were determined by dynamic light-scattering measurements. The average molar mass and mass across the peak showed major increase in R116C and R116H, moderate increase in R12C, R21W, and R54C, and no increase in R21L and R49C as compared to αA-wt. PDI and Rh values were significantly increased only in R116C and R116H. Significant secondary structural changes, as determined by CD measurements, were seen in R21W, R21L, R116C, and R116H, and tertiary structural changes were evident in R21W, R54C, R116C, and R116H. Non-reducing SDSPAGE has shown the presence of dimers presumably formed by inter-polypeptide disulfide bonds. Chaperone activity, as measured with ADH as the target protein, appeared normal in R49C and R54C, while R12C, R21L, and R21W showed moderate loss and R116C and R116H showed significant loss. Although a specific change in the αA-crystallin behavior that is common to all the mutants was not evident, each mutant showed one or more perturbation as the end effect that leads to cataract.

In the transition from paper to electronic workflow, the University of Colorado Health System's implementation of a new electronic health record system (EHR) forced all clinical groups to reevaluate their practices including the infrastructure surrounding clinical trials. Radiological imaging is an important piece of many clinical trials and requires a high level of consistency and standardization. With EHR implementation, paper orders were manually transcribed into the EHR, digitizing an inefficient work flow. A team of schedulers, radiologists, technologists, research personnel, and EHR analysts worked together to optimize the EHR to accommodate the needs of research imaging protocols. The transition to electronic workflow posed several problems: (1) there needed to be effective communication throughout the imaging process from scheduling to radiologist interpretation. (2) The exam ordering process needed to be automated to allow scheduling of specific research studies on specific equipment. (3) The billing process needed to be controlled to accommodate radiologists already supported by grants. (4) There needed to be functionality allowing exams to finalize automatically skipping the PACS and interpretation process. (5) There needed to be a way to alert radiologists that a specialized research interpretation was needed on a given exam. These issues were resolved through the optimization of the "visit type," allowing a high-level control of an exam at the time of scheduling. Additionally, we added columns and fields to work queues displaying grant identification numbers.The build solutions we implemented reduced the mistakes made and increased imaging quality and compliance.

Epidemiological studies have linked obesity with basal-like breast cancer risk in both premenopausal and postmenopausal women, suggesting that obesity may affect tumor phenotype by skewing the microenvironment toward support of more aggressive tumor cell phenotypes (typically ER/PR−, HER-2−). In order to study the interactions between adipocytes and breast tumor cells, we developed an adipocyte-breast cancer cell co-culture system. The adipocytes SGBS (Simpson-Golabi-Behmel Syndrome) and human ER positive breast cancer MCF7 cells were co-cultured for 24 hours. Following co-culture, the cells from the inserts (MCF7 cells) and wells (SGBS cells) were collected separately and total RNA was then isolated. The mRNA levels of the NADPH oxidase subunit NOX4 and hypoxia-inducible factor 1α (HIF1α) were determined by RT-PCR and normalized to 18S RNA levels. When SGBS cells were co-cultured with MCF7 cells, SGBS NOX4 and HIF1α mRNA levels increased more than 10 fold and 3 fold, respectively, while there were no changes in NOX4 and HIF1α expression detected in co-cultured MCF7 cells. We also compared several epithelial-mesenchymal transition (EMT) process-related gene expression levels. Expression in MCF7 cells of the EMT-inducing transcription factors FOXC2 and Twist1 were increased more than 8 fold and 5 fold respectively, after co-culture with SGBS. E-cadherin mRNA level was decreased 2 fold, while N-cadherin mRNA level was increased more than 6 fold in co-cultured MCF7. We also found that mRNA levels of ER-α were significantly (p<0.05) repressed in MCF7 cells co-cultured with SGBS cells. To explore the mechanism of the effect of adipocyte co-culture on ER expression in breast cancer cells, SGBS cells were transfected with 30nM of siHIF1α for 48 hours before co-culture with MCF7 cells. ER gene expression level did not change in MCF7 cells co-cultured with SGBS cells that had been transfected with siHIF1α. In summary, we have shown that adipocytes and breast tumor cells interact with each other: MCF7 cells increased hypoxia and oxidative stress in SGBS cells, while SGBS increased the expression of EMT-inducing factor genes in MCF7 cells, as well as repressing ER expression. This repression was controlled, at least in part, by HIF1α. These results suggest that hypoxia and oxidative stress from adipocytes can modify ER gene expression and promote EMT processes in breast cancer cells, supporting an important role of obesity in aggressive breast cancer development. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 57. doi:1538-7445.AM2012-57