Plasma Leptin, hTERT Gene Expression, and Anthropometric Measures in Obese and Non-Obese Women with Breast Cancer

Introduction Expression of human telomerase reverse transcriptase (hTERT) occurs in most cancers but its relation with obesity is unclear. This study explores the association between leptin levels and anthropometric indices with hTERT mRNA levels in breast cancer patients of different obesity grades. Materials and methods In this case-control study, 65 breast cancer patients participated. Expression of tissues hTERT mRNA was carried out by real-time reverse transcription polymerase chain reaction. Leptin concentrations were measured by enzyme-linked immunoassay. Results Twelve patients (18.46%) were hTERT negative and 53(81.54%) were positive. hTERT mRNA levels were associated with BMI but not with waist circumference (WC) (r = 0.219, P = 0.22) and waist to hip ratio (WHR) (r = 0.212, P = 0.237). Leptin level and hTERT mRNA levels (r = 0.484, P = 0.008) were correlated as well as BMI and hTERT expression. Conclusions This study has shown a correlation between leptin levels and hTERT expression. These findings may clarify the role of leptin in breast carcinogenesis, and hence obesity could be responsible for increased incidences in breast cancer as well as its progression via enhanced production of leptin

Constitutively Nuclear FOXO3a Localization Predicts Poor Survival and Promotes Akt Phosphorylation in Breast Cancer

Background: The PI3K-Akt signal pathway plays a key role in tumorigenesis and the development of drug-resistance. Cytotoxic chemotherapy resistance is linked to limited therapeutic options and poor prognosis. Methodology/Principal Findings: Examination of FOXO3a and phosphorylated-Akt (P-Akt) expression in breast cancer tissue microarrays showed nuclear FOXO3a was associated with lymph node positivity (p = 0.052), poor prognosis (p = 0.014), and P-Akt expression in invasive ductal carcinoma. Using tamoxifen and doxorubicin-sensitive and -resistant breast cancer cell lines as models, we found that doxorubicin- but not tamoxifen-resistance is associated with nuclear accumulation of FOXO3a, consistent with the finding that sustained nuclear FOXO3a is associated with poor prognosis. We also established that doxorubicin treatment induces proliferation arrest and FOXO3a nuclear relocation in sensitive breast cancer cells. Induction of FOXO3a activity in doxorubicin-sensitive MCF-7 cells was sufficient to promote Akt phosphorylation and arrest cell proliferation. Conversely, knockdown of endogenous FOXO3a expression reduced PI3K/Akt activity. Using MDA-MB-231 cells, in which FOXO3a activity can be induced by 4-hydroxytamoxifen, we showed that FOXO3a induction up-regulates PI3K-Akt activity and enhanced doxorubicin resistance. However FOXO3a induction has little effect on cell proliferation, indicating that FOXO3a or its downstream activity is deregulated in the cytotoxic drug resistant breast cancer cells. Thus, our results suggest that sustained FOXO3a activation can enhance hyperactivation of the PI3K/Akt pathway. Conclusions/Significance: Together these data suggest that lymph node metastasis and poor survival in invasive ductal breast carcinoma are linked to an uncoupling of the Akt-FOXO3a signaling axis. In these breast cancers activated Akt fails to inactivate and re-localize FOXO3a to the cytoplasm, and nuclear-targeted FOXO3a does not induce cell death or cell cycle arrest. As such, sustained nuclear FOXO3a expression in breast cancer may culminate in cancer progression and the development of an aggressive phenotype similar to that observed in cytotoxic chemotherapy resistant breast cancer cell models. © 2010 Chen et al.published_or_final_versio

Latent transforming growth factor binding protein 4 (LTBP4) is downregulated in mouse and human DCIS and mammary carcinomas

Transforming growth factor beta (TGF-) is able to inhibit the proliferation of epithelial cells and is involved in the carcinogenesis of mammary tumors. Three latent transforming growth factor- binding proteins (LTBPs) are known to modulate TGF- functions. The current study analyses the expression profiles of LTBP4, its isoforms LTBP1 and LTBP3, and TGF-1, TGF-2, TGF-3, and SMAD2, SMAD3 and SMAD4 in human and murine (WAP-TNP8) DCIS compared to invasive mammary tumors. Additionally mammary malignant (MCF7, Hs578T, MDA-MB361) and non malignant cell lines (Hs578BsT) were analysed. Microarray, q-PCR, immunoblot, immunohistochemistry and immunofluorescence were used. In comparison to non-malignant tissues (n = 5), LTBP4 was downregulated in all human and mouse DCIS (n = 9) and invasive mammary adenocarcinomas (n = 5) that were investigated. We also found decreased expression of bone morphogenic protein 4 (BMP4) and increased expression of its inhibitor gremlin (GREM1). Treatment of the mammary tumor cell line (Hs578T) with recombinant TGF-1 rescued BMP4 and GREM1 expression. We conclude that the lack of LTBP4-mediated targeting in malignant mammary tumor tissues may lead to a possible modification of TGF-1 and BMP bioavailability and function

Histidine-epoxy-activated sepharose beads embedded poly (2-hydroxyethyl methacrylate) cryogels for pseudobiospecific adsorption of human immunoglobulin G

The use of highly purified immunoglobulin became among the most powerful adopted strategies in therapeutic trials nowadays. Their role as immunomodulatory and anti-inflammatory agents has widened their scope of use. A novel continuous supermacroporous monolithic cryogels embedded with histidine-epoxy-activated-sepharose beads were synthetized as a new monolithic adsorbents for the separation of immunoglobulin G from human serum. The histidine-epoxy-activated-sepharose beads were embedded into the 2-hydroxyethyl methacrylate (HEMA) cryogels present in frozen aqueous solution inside a plastic syringe. The microstructure morphology of the cryogels was characterized by swelling measurement and scanning electron microscopy. The adsorption of human IgG on the histidine-epoxy-activated-sepharose beads pHEMA cryogels appeared to follow the Langmuir-Freundlich adsorption isotherm model. The maximum IgG adsorption was observed at 4 degrees C and pH 7.4 and was found to be 26.95mg/g of cryogel which is close to that obtained experimentally (24.49mg/g). The cryogels were used for several adsorption-desorption cycles without any negligible decrease in their adsorption capacity

Zonal variations of types II, IX and XI collagen mRNAs in rat epiphyseal cartilage chondrocytes: quantitative evaluation of in situ hybridization by image analysis of radioautography.

International audienceThe spatial-temporal distribution of the mRNAs for type IX and type XI collagens were compared to that of type II collagen mRNA in the tibial epiphyseal plate cartilage of normal growing rats. The mRNAs were detected by in situ hybridization with radio-labelled specific probes and visualized by radioautography. The areas covered by the resulting silver grains were quantified by computer assisted image analysis. The areas in chondrocytes of each zone of the epiphyseal plate cartilage, which correspond to the stages of chondrocyte development and function were determined. Types II, IX and XI mRNAs were present to some extent in chondrocytes of all zones. The distributions of type II and type IX collagen mRNAs were similar with the highest concentrations in the proliferative zone, and the lowest in the resting and calcifying zones chondrocytes. In contrast, type XI collagen mRNA had a different distribution, with the lowest concentration in the resting zone chondrocytes and a significant decrease in the calcifying zone chondrocytes. These patterns correlates with the changes in chondrocyte function, and may reflect the roles of the type IX and type XI collagens. The data show that computer assisted image analysis of in situ hybridization radioautographic images is a precise, rapid tool for analysing differences in gene expression.The spatial-temporal distribution of the mRNAs for type IX and type XI collagens were compared to that of type II collagen mRNA in the tibial epiphyseal plate cartilage of normal growing rats. The mRNAs were detected by in situ hybridization with radio-labelled specific probes and visualized by radioautography. The areas covered by the resulting silver grains were quantified by computer assisted image analysis. The areas in chondrocytes of each zone of the epiphyseal plate cartilage, which correspond to the stages of chondrocyte development and function were determined. Types II, IX and XI mRNAs were present to some extent in chondrocytes of all zones. The distributions of type II and type IX collagen mRNAs were similar with the highest concentrations in the proliferative zone, and the lowest in the resting and calcifying zones chondrocytes. In contrast, type XI collagen mRNA had a different distribution, with the lowest concentration in the resting zone chondrocytes and a significant decrease in the calcifying zone chondrocytes. These patterns correlates with the changes in chondrocyte function, and may reflect the roles of the type IX and type XI collagens. The data show that computer assisted image analysis of in situ hybridization radioautographic images is a precise, rapid tool for analysing differences in gene expression