21 research outputs found
Over-expression of β-catenin is associated with high grade of prostatic cancer in Libyan patients
Objectives: At present, sufficient prognostic markers for prostate cancer (PCa) progression are still lacking, in spite of thorough investigation. The aim of this study was to evaluate abnormalities of β-catenin protein expression, subcellular localization and determine its relation to different clinicopathological features anddisease free survival in prostate cancer patients.Patients and methods: Forty prostate cancer specimens, obtained from patients with different stages of prostate cancer (83% stage IV) who underwent a radical prostatectomy or TURP flanked by 2006 and 2011, β-catenin was determined by immuno-histochemistry (IHC). The membranous expression was semi- quantitatively evaluated in four scores (0, 1+, 2+, 3+). Clinical records of these patients were studied for follow up data.Results: β-Catenin immune staining results show over-expression of β-catenin in PCa Libyan patients. There was no statistically significant difference in β-catenin immune expression as regards histopathological type, perineural invasion, tumor stage, biological recurrence. However, β-catenin over-expression showed significant correlation with old age (p < 0.014).Conclusions: We concluded that changes in expression and cell distribution of β-catenin correlated with the progression degree of prostate adenocarcinoma, signifying a role of this molecule as a marker of progression and prognosis. Further investigations, on a larger and more heterogeneous population, should be carried out to validate and extend our results.Keywords: Prostate cancer; β-Catenin expression; Immuno-histochemistry; Gleason score; Prognosi
Detection of hCG Responsive Expression of the Steroidogenic Acute Regulatory Protein in Mouse Leydig Cells
The steroidogenic acute regulatory (StAR) protein, a novel mitochondrial protein, is involved in the regulation of steroid hormone biosynthesis through its mediation of the intramitochondrial transport of the steroid substrate, cholesterol, to the cytochrome P450 cholesterol side chain cleavage (P450scc) enzyme. The expression of StAR protein is regulated by cAMP-dependent signaling in steroidogenic cells. During the course of our studies in mouse Leydig cells, we employ several methods for studying the regulation of StAR protein expression by human chorionic gonadotropin (hCG). A sensitive quantitative reverse transcription and polymerase chain reaction (RT-PCR) was utilized for determining StAR mRNA expression. Stimulation of mLTC-1 mouse Leydig tumor cells with hCG resulted in the coordinate regulation of StAR mRNA expression and progesterone accumulation in a time-response manner. The validity and accuracy of quantitative RT-PCR results in mLTC-1 cells were verified by a competitive PCR approach and were further confirmed in primary cultures of isolated mouse Leydig cells. Immunoblotting studies demonstrated an increase in the levels of the StAR protein in a concentration dependent manner following hCG stimulation in mLTC-1 cells. Northern hybridization analysis revealed three StAR transcripts, all of which were of sufficient size to encode functional StAR protein, and which were coordinately expressed in response to hCG. Collectively, the experimental approaches utilized in the present investigation allow for the demonstration and characterization of hCG mediated regulation of StAR mRNA and StAR protein expression in mouse Leydig cells