Evaluation of a new tumor marker for localized prostate cancer

Identification of hepatocellular carcinoma-associated hub genes and pathways by integrated microarray analysis

AIMS AND BACKGROUND

Hepatocellular carcinoma (HCC) is a dismal malignancy associated with multiple molecular changes. The purpose of this study was to identify the differentially expressed genes and analyze the biological processes related to HCC.

METHODS AND STUDY DESIGN

Datasets of HCC were obtained from the NCBI Gene Expression Omnibus. Integrated analysis of differentially expressed genes was performed using the INMEX program. Then Gene Ontology enrichment analyses and pathway analysis were performed based on the Gene Ontology website and Kyoto Encyclopedia of Genes and Genomes. A protein-protein interaction network was constructed using the Cytoscape software; the netwerk served to find hub genes for HCC. Real-time RT-PCR was used to validate the microarray data for hub genes.

RESULTS

We identified 273 genes that were differentially expressed in HCC. Gene Ontology enrichment analyses revealed response to cadmium ion, cellular response to cadmium ion, and cellular response to zinc ion for these genes. Pathway analysis showed that significant pathways included fatty acid metabolism, butanoate metabolism, and PPAR signaling pathway. The protein-protein interaction network indicated that CDH1, ECHS1, ACAA1, MT2A, and MYC were important genes which participated in many interactions. Experimental validation of the role of four upregulated genes (ECHS1, ACAA1, MT2A and MYC) in the progression of HCC was carried out.

CONCLUSIONS

Our study displayed genes that were consistently differentially expressed in HCC. The biological pathways and protein-protein interaction networks associated with those genes were also identified. We predicted that CDH1, ECHS1, ACAA1, MT2A, and MYC might be target genes for diagnosing HCC.

Cellular PSA in benign and malignant prostate

To determine the relationship of carcinoma of the prostate and cellular production of prostate-specific antigen, cytosol levels of PSA were measured in benign and malignant fresh prostate tissue harvested from radical prostatectomy specimens. Wedge biopsies were taken from benign (N = 21) and malignant (N = 74) prostate tissue and were immediately fixed in liquid nitrogen, and then homogenized and differentially centrifuged, and the cytosol fractions extracted. The remaining specimen was sent for routine pathologic assessment. The Hybritech methodology was used to measure the cytosol PSA and standard protein analysis was used for cytosol protein (CP) measurement. There was a significantly greater concentration of PSA in malignant tissue (P = 0.046). Also, when benign and malignant tissue were available from a single prostate (N = 17), these differences in cytosol PSA were even greater (P = 0.002). In addition, there was no significant difference when serum PSAs from the malignant tissue were ranked according to Gleason score and placed into three different histologic grades (i.e., Gleason scores 2-4, 5-6, and 7-10).