View clinical trials related to Carcinogenesis.
Filter by:The long-term outcomes of branched-chain amino acid (BCAA) administration in patients undergoing hepatic resection remain unclear. The aim of this study is to assess the impact of oral supplementation with BCAA on the prevention for the development of liver tumorigenesis in patients undergoing liver resection.
In the United States, overweight (BMI > 25 but < 30 Kg/m2) and obesity (BMI > 30Kg/m2) are increasing at epidemic rates. A significant association exists between being overweight or obese and breast cancer recurrence and survival. However, evidence continues to accumulate indicating that achieving or maintaining a healthy weight for height (Body Mass Index, BMI, 18.5-25Kg/m2) is associated with a reduced risk for breast cancer and with a decrease in breast cancer associated mortality. Despite this, there is a lack of randomized controlled trials exploring this association and how the process of fat loss or being successful in actually reaching a healthy weight for height differentially affects biomarkers for cancer recurrence. Many dietary approaches for weight loss are currently available to the public, and each purports to offer advantages. However, there is little scientific evidence to indicate how these dietary approaches, some of which vary markedly in the foods that they limit or exclude, affect biomarkers for breast cancer risk. In particular, it is not know whether the critical factor in relation to weight and breast cancer is simply weight loss (negative energy balance), irrespective of the manner in which it is achieved, or if certain dietary approaches affect breast cancer risk biomarkers more favorably than others. Published data from our laboratory suggest that dietary pattern does matter, and therefore the goal of this study is to investigate the effects of two popular weight loss dietary approaches that differ in the extent to which they limit carbohydrate or fat consumption (with effects on dietary glycemic load) compared to a usual care group on prognostic markers for cancer recurrence in postmenopausal breast cancer survivors. The investigators hypothesize that in addition to the anticipated effects of fat loss on circulating levels of bioavailable sex steroid hormones, that the effects of excess fat on breast cancer prognosis can be attributed to three interrelated metabolic processes that affect cancer progression: altered glucose metabolism, chronic inflammation and excessive cellular oxidation.
The primary aim of this study is to determine if mutations of BRCA1 and BRCA2 result in different precancerous pathways to pancreatic ductal adenocarcinoma (PDAC), as suggested in our validated mouse model. Genomic DNA will be isolated on normal tissue obtained from patients who underwent pancreatic resection for PDAC, intraductal papillary mucinous neoplasm (IPMN) or mucinous cystic neoplasm (MCN). Tissue will be examined for the three most common founder mutations in Ashkenazi Jews. In the cases in which BRCA1 or BRCA2 mutations are found, heterozygote normal and abnormal tissue will be examined to look for mutations in the other BRCA1 or BRCA2 allele. The interaction between other cancer causing genes with BRCA1/2 will also be evaluated by comparing the sequences of the other genes in pre-cancerous lesions. We hypothesize that BRCA1- and BRCA2-mediated pancreatic ductal adenocarcinoma progresses through the PanIN route, as seen in both BRCA1 and BRCA2 murine models of pancreatic cancer. We further hypothesize that BRCA1 mutations may enable an additional pre- neoplastic pathway through MCN, and that IPMN may embody yet another pre- neoplastic pathway.
Neuroblastoma (NB) is the most common malignant tumor of infancy. Approximately 60% of NB patients are clinically diagnosed as the stage IV disease and have a very poor prognosis with the 5-year survival rate no more than 30%. Molecular markers of NB have great impacts on the tumor behavior. MYCN amplification is the most well-known marker to predict a poor outcome in NB patients. However, how MYCN affects the NB cell behavior remains unknown. In our preliminary studies, we performed a genome-wide analysis of the differential gene expression in 10 NB tumors with MYCN amplification and 10 with normal MYCN copy number. We found that aromatic hydrocarbon receptor (AHR) reversely correlated with the MYCN expression. This relationship was verified in 83 NB tumor samples. In addition, positive AHR expression by immunostaining of NB tumors predicted a favorable prognosis. These lines of evidence demonstrate that AHR not only relates to the MYCN expression but also plays an important role in the tumorigenesis of NB. Therefore in this project we aim at further studying the relationship between AHR and MYCN. In addition, the possible role of AHR in the tumorigenesis of NB will be clarified. Specifically, we propose a 3-year project with the following three aims: Aim I. Determine the molecular relationship between AHR and MYCN expression. AHR has been shown to suppress the E2F1 expression. E2F1 reversely has been found to upregulate the expression of MYCN. In our preliminary microarray study, we also found that the expression E2F1 positively correlated with the MYCN expression but inversely correlated with the expression of AHR. Therefore, NB cells will be transfected with AHR expression vector or AHR siRNA, then the associated E2F1 and MYCN expression will be examined to clarify if AHR could regulate MYCN expression via E2F1. Furthermore, the E2F1 levels will also be manipulated to determine if the effect of AHR on MYCN depends on E2F1. In addition, the E2F1 expression in NB tumor samples will also be examined to clarify its in vivo role. Aim II. Determine the effect of AHR expression on the NB cell behavior. The baseline AHR expression levels in several NB cell lines will be examined. AHR is then overexpressed by gene transfection in NB cells. The cell proliferation, migration, and differentiation after AHR overexpression are evaluated. Furthermore the AHR expression in normal neuron cells is also examined, and suppressed by siRNA to if downregulation of AHR could lead to cancer development. Aim III. Determine if AHR could be a target of gene therapy for NB. NB cells with either normal MYCN or MYCN amplification before and after AHR gene transfection are inoculated into nude mice to demonstrate the effect of AHR expression on NB cells behavior in vivo. AHR is then transfected into the wild type NB tumor to see if the tumor growth could be suppressed by AHR expression. Then wild type tumor and tumors transfected with AHR are subjected microarray analysis to compare with the human tumor data set for evaluation of gene expression changes along with differential AHR expression. Altogether, our studies will not only establish the relationship between AHR and MYCN, but also allow us to depict the functional role of AHR-MYCN interaction in the tumorigenesis of NB.
Colorectal cancer kills forty five people in France every day. Epidemiological studies suggest that two cases out of three could be prevented and show that processed meat intake is a consistent risk factor. The aim of this study is to understand how meat promotes cancer, to find protective strategies, and to make compelling dietary recommendations.
The purposes of this study are the following: 1. To further characterize and quantify both CSF-1 and colony-stimulating factor-1 receptor (CSF-1R) expression from additional tumor specimens, specifically, tumors of high grade and from metastatic sites. 2. To assay using Enzyme-Linked ImmunoSorbent Assay (ELISA) sandwich monoclonal antibody methodology, CSF-1 expression in the peritoneal fluid and blood from patients with endometrial adenocarcinomas. 3. Using immunohistochemistry, to evaluate the presence of staining for CSF-1 and CSF-1R from additional patients with endometrial adenocarcinomas, especially of high grades and from metastatic sites. 4. To determine the extent of cytokine, specifically CSF-1, but also interleukin-1 (IL-1), IL-6, and granulocyte-macrophage colony-stimulating factor (GM-CSF), production, in endometrial carcinoma cells in primary cell culture. 5. To determine the responsiveness of epithelial cells on estrogen and antiestrogen binding, to determine if CSF-1 production is mediated, in these cells, by estrogen receptor binding, or alternative pathways of intracellular/cell-cell signal transduction. 6. The ultimate objective of these experiments is to characterize CSF-1 expression from benign and tumor cells in order to identify steps in the CSF-1 activated signalling pathways that may represent potential targets for therapy.