Project description:The incidence and mortality rates of prostate cancer are significantly higher in African-American men when compared to European-American men. We tested the hypothesis that differences in tumor biology contribute to this survival health disparity. Using microarray technology, we obtained gene expression profiles of primary prostate tumors resected from 33 African-American and 36 European-American patients. These tumors were matched on clinical parameters. We also evaluated 18 non-tumor prostate tissues from 7 African-American and 11 European-American patients. The resulting datasets were analyzed for expression differences on the gene and pathway level comparing African-American with European-American patients. Our analysis revealed a significant number of genes, e.g., 162 transcripts at a false-discovery rate less than 5%, to be differently expressed between African-American and European-American patients. Using a disease association analysis, we identified a common relationship of these transcripts with autoimmunity and inflammation. These findings were corroborated on the pathway level with numerous differently expressed genes clustering in immune response, stress response, cytokine signaling, and chemotaxis pathways. Furthermore, a two-gene tumor signature was identified that accurately differentiated between African-American and European-American patients. This finding was confirmed in a blinded analysis of a second sample set. In conclusion, the gene expression profiles of prostate tumors indicate prominent differences in tumor immunobiology between African-American and European-American men. The profiles portray the existence of a distinct tumor microenvironment in these two patient groups. Experiment Overall Design: A total of 69 fresh-frozen prostate tumors were obtained from the NCI Cooperative Prostate Cancer Tissue Resource (CPCTR) and the Department of Pathology at the University of Maryland (UMD). All tumors were resected adenocarcinomas that had not received any therapy prior to prostatectomy. The macro-dissected CPCTR tumor specimens (n = 59) were reviewed by a CPCTR-associated pathologist, who confirmed the presence of tumor in the specimens. These tissues were collected between 2002 and 2004 at four different sites, with each site providing tissues from both African-American and European-American patients. Information on race/ethnicity (33 African-Americans and 36 European-Americans) was either extracted from medical records (CPCTR) or obtained through an epidemiological questionnaire in which race/ethnicity was self-reported (UMD). Only one patient, a European-American, was also Hispanic. Surrounding non-tumor prostate tissue was collected from 18 of the recruited patients in this study. Of those, 7 were African-American men and 11 were European-American men. We also isolated total RNA from 10 needle biopsy specimens collected from patients at the National Naval Medical Center (one African-American and 9 European-Americans) that did not have prostate cancer. From those, we prepared two RNA pools, each representing 5 patients. Clinicopathological characteristics of the patients, including age at prostatectomy, histology, Gleason score, pathological stage, PSA at diagnosis, tumor size, extraprostatic extension, margin involvement, and seminal vesicle invasion were obtained from CPCTR. For UMD cases, this information was extracted from the medical and pathology records, if available. Written informed consent was obtained from all donors. Tissue collection and study design were approved by the institutional review boards of the participating institutions.
Project description:hormonal progression in prostate cancer fiber model Experiment Overall Design: The LNCaP Hollow Fiber model of prostate cancer was appied. A total of 24 fibers were implanted in each animal, in bundles of eight fibers at three different regions in the animal. Castration of mice was performed At each time point, eight fibers from the same mouse were harvested and total RNA was isolated from LNCaP cells grown inside the fibers using Trizol
Project description:Prostate cancer gene expression profiles were studied in this project. A total RNA from 148 prostate sample with various amount of different cell types were hybridized to Affymetrix U133A arrays. The percentage of different cell types vary considerably among samples and were determined by pathologist. Cell type specific genes can be determined by linear regression using the methods of Stuart et al, PNAS, 2004. Experiment Overall Design: 148 prostate samples, with various amounts of tumor, stroma, BPH and atrophic gland, were used for this study.
Project description:Protein 4.1B is a 4.1/ezrin/radixin/moesin (FERM) domain-containing protein whose expression is frequently lost in a variety of human tumors, including meningiomas, non-small-cell lung cancers and breast carcinomas. However, its potential tumor suppressive function under in vivo conditions remains to be validated. In a screen for genes involved with prostate cancer metastasis, we found that 4.1B expression is reduced in highly metastatic tumors. Downregulation of 4.1B increased the metastatic propensity of poorly metastatic cells in an orthotopic model of prostate cancer. Furthermore, 4.1B-deficient mice displayed increased susceptibility for developing aggressive, spontaneous prostate carcinomas. In both cases, enhanced tumor malignancy was associated with reduced apoptosis. As expression of Protein 4.1B is frequently downregulated in human clinical prostate cancer, as well as in a spectrum of other tumor types, these results suggest a more general role for Protein 4.1B as a negative regulator of cancer progression to metastatic disease. Experiment Overall Design: primary cell line vs metastasis cell line
Project description:In our investigations of the molecular pathways of prostate tumorigenesis in Nkx3.1; Pten mutant mice using gene expression profiling, we now find that the AP-1 transcription factors, c-Jun and c-Fos, are significantly up-regulated during cancer progression. Forced expression of c-Fos and c-Jun in prostate cancer cells results in increased tumorigenicity, activation of Erk MAP kinase, and enhanced survival in the absence of androgens, which are hallmarks of disease progression. In humans, Jun and Fos proteins are significantly up-regulated during prostate cancer progression and significantly correlated with activation of Erk MAP kinase. Most notably, expression of Jun is associated with disease recurrence independent of other currently used prognostic indicators. These analyses reveal a hitherto unappreciated role for AP-1 transcription factors in prostate cancer progression vis-à -vis Erk MAP kinase signaling, as well as the identification of a novel marker of disease recurrence, namely c-Jun. Experiment Overall Design: Mouse prostate was collected from wild-type or the Nkx3.1; Pten compound mutant mice at the age of 8-16 months. One lobe of dosolateral prostate was snap-frozen in OCT and stored at -80ºC for laser capture microdissection (LCM). To obtain androgen-independent lesions, mice were castrated at 7 to 14 months of age. Mice were sacrificed for analysis at 8 to 16 months of age and one dosolateral prostatic lobe was snap-frozen in OCT and stored at -80ºC for LCM. Approximate 1000 Prostate epithelial cells were isolated from normal prostate, dysplasia, prostatic intraepithelial neoplasia (PIN) or cancer lesions using PixCell IIE LCM system (Arcturus), followed by RNA linear amplification and labeling using Small Sample Labeling Protocol VII (Affymetrix). Samples were labeled using a BioArray High Yield RNA transcript labeling kit (Enzo Life Scientific) and were hybridized to MOE430A GeneChips containing 22,690 well characterized mouse genes/ESTs (Affymetrix).
Project description:Integrated Proteomic and Glycoproteomic Analyses of Prostate Cancer Cells Reveals Glycoprotein Alteration in Protein Abundance and Glycosylation
Project description:Integrated Proteomic and Glycoproteomic Analyses of Prostate Cancer Cells Reveals Glycoprotein Alteration in Protein Abundance and Glycosylation