miR-15a and miR-16-1 down-regulation in pituitary adenomas.

Abstract

Micro RNAs (miRs) are small noncoding RNAs, functioning as antisense regulators of other RNAs. miR-15a and miR-16-1 genes are located at chromosome 13q14, a region which is frequently deleted in pituitary tumors. An inverse correlation has been shown in B cell chronic lymphocytic leukemia (B-CLL) between miR-15a and miR-16-1 expression and the expression levels of arginyl-tRNA synthetase (RARS), an enzyme which associates with the cofactor p43 in the aminoacyl-tRNA synthetase complex. When secreted, p43 regulates local inflammatory response and macrophage chemotaxis, and seems to have anti-neoplastic properties in mice. We explored miR-15a and miR-16-1 expression in 10 GH-secreting and in 10 PRL-secreting pituitary macroadenomas by Northern blot, and investigated the possible correlation with in vivo and in vitro characteristics. We found that miR-15a and miR-16-1 are expressed at lower levels in pituitary adenomas as compared to normal pituitary tissue. Moreover, their expression inversely correlates with tumor diameter and with RARS expression (P < 0.05), but directly correlates with p43 secretion (P < 0.02). Therefore, miR15 and miR16 down-regulation in pituitary adenomas correlates with a greater tumor diameter and a lower p43 secretion, suggesting that these genes may, at least in part, influence tumor growth.

• Authors: Arianna Bottoni, Daniela Piccin, Federico Tagliati, Andrea Luchin, Maria Chiara Zatelli, Ettore C degli Uberti
• Journal: Journal of cellular physiology (J Cell Physiol) Vol. 204 Issue 1 Pg. 280-5 (Jul 2005) ISSN: 0021-9541 [Print] United States
• PMID: 15648093 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: (c) 2004 Wiley-Liss, Inc.

Chemical References

• Antigens, Neoplasm
• MicroRNAs
• Mitochondrial Proteins
• TUFM protein, human
• Peptide Elongation Factor Tu
• Arginine-tRNA Ligase

Topics

• Adenoma (genetics, physiopathology)
• Adolescent
• Adult
• Aged
• Antigens, Neoplasm
• Arginine-tRNA Ligase (genetics)
• Down-Regulation
• Female
• Gene Deletion
• Gene Expression Regulation, Neoplastic (physiology)
• Humans
• Male
• MicroRNAs (physiology)
• Middle Aged
• Mitochondrial Proteins
• Peptide Elongation Factor Tu (metabolism)
• Pituitary Gland (physiology)
• Pituitary Neoplasms (genetics, physiopathology)