Inhibition of all-trans retinoic acid on MDM2 gene expression in astrocytoma cell line SHG-44

Abstract

Objective To investigate the impact of all-trans retinoic acid (ATRA) on MDM2 gene expression in astrocytoma cell line SHG-44, and to provide basic data for further research on the progression mechanism and gene therapy of human astrocytoma. Methods The differential expressions of MDM2 gene and protein in SHG-44 cells were detected by cDNA microarray and Western blot, respectively, before and after treatment of ATRA. The expressions of MDM2 protein in WHO grade II and grade IV astrocytomas were determined by immunohistochemical streptavidin-peroxidase method. Some differentially expressed genes were selected randomly for Northern blot analysis. Results The intensity ratio of ATRA-treated to untreated SHG-44 cell was 0.37 in the cDNA microarray, suggesting that the expression of MDM2 gene was down-regulated in SHG-44 cells after treatment with ATRA. Some genes differentially expressed in the microarray were confirmed by Northern blot. Western blot demonstrated that the optical density ratios of MDM2 to β-actin in ATRA-treated and untreated SHG-44 were 14.02±0.35 and 21.40±0.58 (t = 24.728, P = 0.000), respectively, suggesting that the expression of MDM2 protein was inhibited in ATRA-treated SHG-44 cells. Moreover, the percentages of MDM2-positive protein were 24.00% (6/25) and 56.52% (13/23) (χ 2 = 5.298, P = 0.021) in WHO grade II and grade IV astrocytomas, respectively, suggesting that the expression of MDM2 protein may increase along with the elevation of astrocytoma malignancy. Conclusion ATRA can inhibit MDM2 gene expression in SHG-44 cells, and MDM2 is related to astrocytoma progression.

Elevated transcriptional levels of aldolase A (ALDOA) associates with cell cycle-related genes in patients with NSCLC and several solid tumors

“…Additionally, in previous studies, positive effect of ALDOA on initialization and progression of other cancers, such as colorectal cancer, oral tumor, osteosarcoma and hepatocellular carcinoma, had also been demonstrated [ 5 – 8 ]. Moreover, in vitro, ALDOA mRNA levels were down-regulated after glioma cell line SHC-44 cells treated with all-trans retinoic acid [ 25 ]. Compared with melanocytes, the mRNAs of ALDOA were highly expressed in human melanoma cell lines G361 [ 26 ].…”

Identifying suitable reference genes for developing and injured mouse CNS tissues

“…Quantitative real‐time PCR (qPCR), Microarrays and RNA‐seq are commonly used in disease diagnostics and expression studies in various biological systems (Bustin et al, ; Zeng et al, ). Without exception, the accurate quantification of gene expression with all the above methods depends on appropriate reference genes used for data normalization (Aerts et al, ; Nygard et al, ).…”

Μελέτη Μοριακών Παραμέτρων Σε Όγκους Εγκεφάλου Με Στόχο Την Αναγνώριση Δεικτών Πρόβλεψης Ευαισθησίας Σε Στοχευμένη Θεραπεία

“…Όπως προέκυψε από in-vitro μελέτες, η έκφραση του γονιδίου MDM2 στους όγκους γλοίας σχετίζεται με επιθετικά βιολογικά χαρακτηριστικά [391]. Σε κλινικές μελέτες, η υπερέκφραση του γονιδίου θεωρήθηκε αρνητικός προγνωστικός δείκτης [89], ενώ σε άλλες δεν παρατηρήθηκε συσχέτιση με την επιβίωση [379].…”

“…H έκφραση του mRNA ήταν μεγαλύτερη στους όγκους υψηλού βαθμού κακοήθειας. Σε αντίστοιχες μελέτες της mRNA έκφρασης του MDM2, τόσο σε πειραματικό όσο και σε κλινικό επίπεδο (χειρουργικά υλικά), αναφέρονται επίσης αυξημένα επίπεδα έκφρασης στα υψηλού βαθμού κακοήθειας γλοιώματα [88,391]. Γονιδιακή ενίσχυση που αφορά στη χρωμοσωμική περιοχή 12q έχει παρατηρηθεί και σε χαμηλού βαθμού κακοήθειας γλοιώματα, όπως πιλοκυτταρικά και διάχυτα ινιδώδη αστροκυττώματα, αλλά σε αυτές τις περιπτώσεις ενίσχυση παρουσίασαν συχνότερα άλλα γονίδια [88].…”