Phenotypic plasticity in normal breast derived epithelial cells

Background Normal, healthy human breast tissue from a variety of volunteer donors has become available for research thanks to the establishment of the Susan G. Komen for the Cure® Tissue Bank at the IU Simon Cancer Center (KTB). Multiple epithelial (K-HME) and stromal cells (K-HMS) were established from the donated tissue. Explant culture was utilized to isolate the cells from pieces of breast tissue. Selective media and trypsinization were employed to select either epithelial cells or stromal cells. The primary, non-transformed epithelial cells, the focus of this study, were characterized by immunohistochemistry, flow cytometry, and in vitro cell culture. Results All of the primary, non-transformed epithelial cells tested have the ability to differentiate in vitro into a variety of cell types when plated in or on biologic matrices. Cells identified include stratified squamous epithelial, osteoclasts, chondrocytes, adipocytes, neural progenitors/neurons, immature muscle and melanocytes. The cells also express markers of embryonic stem cells. Conclusions The cell culture conditions employed select an epithelial cell that is pluri/multipotent. The plasticity of the epithelial cells developed mimics that seen in metaplastic carcinoma of the breast (MCB), a subtype of triple negative breast cancer; and may provide clues to the origin of this particularly aggressive type of breast cancer. The KTB is a unique biorepository, and the normal breast epithelial cells isolated from donated tissue have significant potential as new research tools

Next-generation transcriptome sequencing of the premenopausal breast epithelium using specimens from a normal human breast tissue bank

Introduction Our efforts to prevent and treat breast cancer are significantly impeded by a lack of knowledge of the biology and developmental genetics of the normal mammary gland. In order to provide the specimens that will facilitate such an understanding, The Susan G. Komen for the Cure Tissue Bank at the IU Simon Cancer Center (KTB) was established. The KTB is, to our knowledge, the only biorepository in the world prospectively established to collect normal, healthy breast tissue from volunteer donors. As a first initiative toward a molecular understanding of the biology and developmental genetics of the normal mammary gland, the effect of the menstrual cycle and hormonal contraceptives on DNA expression in the normal breast epithelium was examined. Methods Using normal breast tissue from 20 premenopausal donors to KTB, the changes in the mRNA of the normal breast epithelium as a function of phase of the menstrual cycle and hormonal contraception were assayed using next-generation whole transcriptome sequencing (RNA-Seq). Results In total, 255 genes representing 1.4% of all genes were deemed to have statistically significant differential expression between the two phases of the menstrual cycle. The overwhelming majority (221; 87%) of the genes have higher expression during the luteal phase. These data provide important insights into the processes occurring during each phase of the menstrual cycle. There was only a single gene significantly differentially expressed when comparing the epithelium of women using hormonal contraception to those in the luteal phase. Conclusions We have taken advantage of a unique research resource, the KTB, to complete the first-ever next-generation transcriptome sequencing of the epithelial compartment of 20 normal human breast specimens. This work has produced a comprehensive catalog of the differences in the expression of protein-coding genes as a function of the phase of the menstrual cycle. These data constitute the beginning of a reference data set of the normal mammary gland, which can be consulted for comparison with data developed from malignant specimens, or to mine the effects of the hormonal flux that occurs during the menstrual cycle

Presence of activating KRAS mutations correlates significantly with expression of tumour suppressor genes DCN and TPM1 in colorectal cancer

<p>Abstract</p> <p>Background</p> <p>Despite identification of the major genes and pathways involved in the development of colorectal cancer (CRC), it has become obvious that several steps in these pathways might be bypassed by other as yet unknown genetic events that lead towards CRC. Therefore we wanted to improve our understanding of the genetic mechanisms of CRC development.</p> <p>Methods</p> <p>We used microarrays to identify novel genes involved in the development of CRC. Real time PCR was used for mRNA expression as well as to search for chromosomal abnormalities within candidate genes. The correlation between the expression obtained by real time PCR and the presence of the <it>KRAS </it>mutation was investigated.</p> <p>Results</p> <p>We detected significant previously undescribed underexpression in CRC for genes <it>SLC26A3</it>, <it>TPM1 </it>and <it>DCN</it>, with a suggested tumour suppressor role. We also describe the correlation between <it>TPM1 </it>and <it>DCN </it>expression and the presence of <it>KRAS </it>mutations in CRC. When searching for chromosomal abnormalities, we found deletion of the <it>TPM1 </it>gene in one case of CRC, but no deletions of <it>DCN </it>and <it>SLC26A3 </it>were found.</p> <p>Conclusion</p> <p>Our study provides further evidence of decreased mRNA expression of three important tumour suppressor genes in cases of CRC, thus implicating them in the development of this type of cancer. Moreover, we found underexpression of the <it>TPM1 </it>gene in a case of CRCs without <it>KRAS </it>mutations, showing that <it>TPM1 </it>might serve as an alternative path of development of CRC. This downregulation could in some cases be mediated by deletion of the <it>TPM1 </it>gene. On the other hand, the correlation of <it>DCN </it>underexpression with the presence of <it>KRAS </it>mutations suggests that <it>DCN </it>expression is affected by the presence of activating <it>KRAS </it>mutations, lowering the amount of the important tumour suppressor protein decorin.</p

Loss of the SxxSS Motif in a Human T-Cell Factor-4 Isoform Confers Hypoxia Resistance to Liver Cancer: An Oncogenic Switch in Wnt Signaling

PURPOSE: Aberrantly activated Wnt/β-catenin signaling is important in hepatocellular carcinoma (HCC) development. Downstream gene expressions involving the Wnt/β-catenin cascade occur through T-cell factor (TCF) proteins. Here, we show the oncogenic potential of human TCF-4 isoforms based on the expression of a single conserved SxxSS motif. METHODS: We investigated the TCF-4J and K isoform pair characterized by the presence (K) or absence (J) of the SxxSS motif. The mRNA expression profiles were examined in 47 pairs of human HCCs and adjacent non-cancerous liver tissues by RT-PCR. Proliferation, sphere assays and immunoblot analysis were performed under normoxia and hypoxia conditions. The ability of HCC cells overexpressing TCF-4J (J cells) and K (K cells) to grow as solid tumors in nude mice was explored. RESULTS: TCF-4J expression was significantly upregulated in HCC tumors compared to corresponding peritumor and normal liver and was preferentially expressed in poorly differentiated HCCs. In contrast, TCF-4K was downregulated in those same HCC tumors. TCF-4J-overexpressing HCC cells (J cells) revealed a survival advantage under hypoxic conditions, high proliferation rate and formation of aggregates/spheres compared to overexpression of TCF-4K (K cells). The hypoxic J cells had high expression levels of HIF-2α and EGFR as possible mechanisms to promote tumorigenesis. Increased stability of HIF-2α under hypoxia in J cells was associated with a decreased level of von Hippel-Lindau (VHL) protein, a known E3 ligase for HIF-αs. In a xenograft model, the J cells rapidly developed tumors compared to K cells. Tumor tissues derived from J cells exhibited high expression levels of HIF-2α and EGFR compared to the slow developing and small K cell derived tumors. CONCLUSIONS: Our results suggest that the specific TCF-4J isoform, which lacks a regulatory SxxSS motif, has robust tumor-initiating potential under hypoxic conditions

Sustainable Waste-to-Energy Technologies: Bioelectrochemical Systems

The food industry produces a large amount of waste and wastewater, of which most of the constituents are carbohydrates, proteins, lipids, and organic fibers. Therefore food wastes are highly biodegradable and energy rich. Bioelectrochemical systems (BESs) are systems that use microorganisms to biochemically catalyze complex substrates into useful energy products, in which the catalytic reactions take place on electrodes. Microbial fuel cells (MFCs) are a type of bioelectrochemical systems that oxidize substrates and generate electric current. Microbial electrolysis cells (MECs) are another type of bioelectrochemical systems that use an external power source to catalyze the substrate into by-products such as hydrogen gas, methane gas, or hydrogen peroxide. BESs are advantageous due to their ability to achieve a degree of substrate remediation while generating energy. This chapter presents an extensive literature review on the use of MFCs and MECs to remediate and recover energy from food industry waste. These bioelectrochemical systems are still in their infancy state and further research is needed to better understand the systems and optimize their performance. Major challenges and limitations for the use of BESs are summarized and future research needs are identified

Energy applications of ionic liquids

Ionic liquids offer a unique suite of properties that make them important candidates for a number of energy related applications. Cation–anion combinations that exhibit low volatility coupled with high electrochemical and thermal stability, as well as ionic conductivity, create the possibility of designing ideal electrolytes for batteries, super-capacitors, actuators, dye sensitised solar cells and thermoelectrochemical cells. In the field of water splitting to produce hydrogen they have been used to synthesize some of the best performing water oxidation catalysts and some members of the protic ionic liquid family co-catalyse an unusual, very high energy efficiency water oxidation process. As fuel cell electrolytes, the high proton conductivity of some of the protic ionic liquid family offers the potential of fuel cells operating in the optimum temperature region above 100 °C. Beyond electrochemical applications, the low vapour pressure of these liquids, along with their ability to offer tuneable functionality, also makes them ideal as CO2 absorbents for post-combustion CO2 capture. Similarly, the tuneable phase properties of the many members of this large family of salts are also allowing the creation of phase-change thermal energy storage materials having melting points tuned to the application. This perspective article provides an overview of these developing energy related applications of ionic liquids and offers some thoughts on the emerging challenges and opportunities

CC Chemokine Ligand 7 Derived from Cancer-Stimulated Macrophages Promotes Ovarian Cancer Cell Invasion

In the tumor microenvironment, macrophages have been suggested to be stimulated by tumor cells, becoming tumor-associated macrophages that promote cancer development and progression. We examined the effect of these macrophages on human ovarian cancer cell invasion and found that conditioned medium of macrophages stimulated by ovarian cancer cells (OC-MQs) significantly increased cell invasion. CC chemokine ligand 7 (CCL7) expression and production were significantly higher in OC-MQs than in the control macrophages. Peritoneal macrophages from patients with ovarian cancer showed higher CCL7 expression levels than those from healthy controls. Inhibition of CCL7 using siRNA and neutralizing antibodies reduced the OC-MQ-CM-induced ovarian cancer cell invasion. CC chemokine receptor 3 (CCR3) was highly expressed in human ovarian cancer cells, and a specific inhibitor of this receptor reduced the OC-MQ-CM-induced invasion. Specific signaling and transcription factors were associated with enhanced CCL7 expression in OC-MQs. CCL7-induced invasion required the expression of matrix metalloproteinase 9 via activation of extracellular signal-related kinase signaling in human ovarian cancer cells. These data suggest that tumor-associated macrophages can affect human ovarian cancer metastasis via the CCL7/CCR3 axis

Gomisin L1, a Lignan Isolated from Schisandra Berries, Induces Apoptosis by Regulating NADPH Oxidase in Human Ovarian Cancer Cells

The fruits of Schisandra chinensis (Schisandra berries) are used as health food supplements and popular food ingredients in East Asia. Lignans, major and characteristic polyphenol compounds of Schisandra berries, possess various biological activities, including hepatoprotective and anticancer effects. However, the biological activities of gomisin L1, a lignan isolated from Schisandra berries, are less to be investigated. In this study, the antitumor activity of gomisin L1 and its underlying molecular mechanism in human ovarian cancer cells were investigated. Gomisin L1 exhibited potent cytotoxic activity against A2780 and SKOV3 ovarian cancer cells. Flow cytometry analysis revealed that the growth inhibitory effects of gomisin L1 were mediated by the induction of apoptosis. Furthermore, gomisin L1 induced an increase in intracellular reactive oxygen species (ROS) levels, and the antioxidant N-acetyl cysteine significantly negated gomisin L1-induced cell death. Moreover, inhibition of NADPH oxidase (NOX) using an inhibitor and siRNA attenuated gomisin L1-induced death of, and ROS production in, human ovarian cancer cells. Taken together, these data indicate that the lignan gomisin L1 from Schisandra berries induces apoptotic cell death by regulating intracellular ROS production via NOX