Project description:To investigate genetic and molecular differences that may exist between prostate cancers of African American and European American origin. Gene expression profile analysis was performed comparing RNA seq data of African American prostate cancer cell lines (inhouse) and European American prostate cancer cell lines (public repository)
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. Keywords: Microdissected tissue analysis
Project description:Epidemiological data have suggested that African Americans (AA) are twice as likely to be diagnosed with multiple myeloma (MM) as compared to European Americans (EA). Here, we have analyzed a set of cytogenetic and genomic data derived from AA and EA MM patients. We have compared the frequency of IgH translocations in a series of data from 115 AA patients from three studies and EA patients from the Eastern Cooperative Oncology Group (ECOG) studies E4A03 and E9487. We have also interrogated tumors from 45 AA and 196 EA MM patients for somatic copy number abnormalities associated with poor outcome. In addition, 35 AA and 178 EA patients were investigated for a transcriptional profile associated with high-risk disease. Overall, based on this cohort, genetic profiles were similar except for a significantly lower frequency of IgH translocations (40% vs. 52%; p=0.032) in AA patients. Frequency differences of somatic copy number aberrations were not significant after correction for multiple testing. There was also no significant difference in the frequency of high-risk disease based upon gene expression profiling. Our study represents the first comprehensive comparisons of the frequency and distribution of molecular alterations in MM tumors between AA and EA patients. This submission contains 27 of the 45 African American cases analyzed by aCGH. In addition, 196 samples from European American myeloma patients were also analyzed and compared to the 45 African American patients.
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:African-Americans with prostate cancer tend to have a more aggressive form of the disease, as compared to their Caucasian counterparts. Nevertheless, African-Americans tend to be underrepresented in most molecular profiling studies of prostate cancer. To investigate DNA copy number alterations (CNAs) in prostate cancer from a cohort of African-Americans, we profiled 20 tumors (each with paired normal) for 500,000 SNPs. Keywords: tumor-normal comparison Profiles were generated on two Affymetrix array chips: Nsp and Sty, each with ~250K SNPs represented. In all, 20 tumors and 20 paired normal samples were profiled, 40 profiles in all. Each tumor was centered on its corresponding normal pair to define copy number alterations (CNA) in that tumor.
Project description:Prostate cancer (PCa) tends to be more aggressive and lethal in African Americans (AA) compared to European Americans (EA). To further understand the biological factors accounting for the PCa disparities observed in AA and EA patients, we performed gene profiling using Affymetrix human exon 1.0 ST arrays to identify the differentially expressed genes beween AA cancer and patient matched normal tissues. 40 prostate biopsy specimens (tumor and adjacent normal tissues) were collected from 20 African American prostate cancer patients. RNA samples, purified from the collected biopy specimens, were process and applied to Affymetrix human exon ST 1.0 arrays. Array data was normalized, batch-corrected and analyzed (2-way ANOVA) using Partek Genomics Suite program.
Project description:African American (AA) men have a significantly higher mortality rate from prostate cancer (PCa) compared to European American (EA) men. AA men are twice as likely to die from PCa compared to EA men and 8 times as likely as Asian American men to die from PCa. The biological basis for these differences in PCa mortality are unclear. We carried out Copy Number Alteration (CNA) studies on a new set of 40 highly tumor-enriched primary PCas and matched benign prostate tissues from AA men using high resolution Affymetrix 6.0 SNP arrays and expression array analysis using RNAs (GSE71016) from the same tissues using high purity tumors from AA men and matched benign tissue. We have confirmed the specific loss of 4p16.3 described previously and identified a novel tumor suppressor gene, RGS12 at this locus that shows significantly decreased expression in AA PCa but not EA EA PCa.
Project description:Laser Capture Microdissected cells from archival FFPE Prostate cancer and normal adjacent tissues from 10 patients (5 CA and 5 AA) were converted to cDNA and analysed by PCR array to identify differentially expressed miRNAs between the groups. Selected differentially expressed miRNAs were further validated in tissues from 40 prostate cancer patients. The miRNAs which were differentially modulated in PCa patients in the validation set were further analysed in 32 urine samples from PCa patients and compared with 12 healthy individuals. Differentially expressed miRNAs were explored to e used as non-invasive biomarker for PCa. qPCR miRNA expression profiling. mRNA from 10 Prostate Cancer patients (5 Caucasian American and 5 African American) and their paired adjacent normal tissue were analysed to identify the differentially expressed miRNA between the groups. Equal amount small RNA from each group was pooled prior to gene expression analysis.
Project description:Prostate cancer (PCa) tends to be more aggressive and lethal in African Americans (AA) compared to European Americans (EA). To further understand the biological factors accounting for the PCa disparities observed in AA and EA patients, we performed gene profiling analysis using Affymetrix human exon 1.0 ST arrays to identify the differentially expressed genes in AA and EA patients. 35 prostate biopsy specimens (tumor and adjacent normal tissues) were collected from 20 African American and 15 European American prostate cancer patients. RNA samples, purified from the collected biopy specimens, were process and applied to Affymetrix human exon ST 1.0 arrays. Array data was normalized, batch corrected and analyzed (1-way ANOVA) using Partek Genomics Suite program.