Regulation of cell invasion and signalling pathways in the pituitary adenoma cell line, HP-75, by reversion-inducing cysteine-rich protein with kazal motifs (RECK).
Degradation and remodelling of the extracellular matrix has been investigated, with the main focus on the balance between matrix metalloproteinases (MMP) and tissue inhibitor of metalloproteinases (TIMP). Recent reports disclose the presence of a novel MMP-inhibiting cell membrane-anchored glycoprotein designated 'reversion-inducing cysteine-rich protein with Kazal motifs' (RECK). Our main aim in this study was to elucidate the role of RECK in cell invasion of pituitary adenomas and its contribution to signal transduction. The function of RECK in cell invasion was investigated by comparing data obtained from full-length RECK clone transfection and gene silencing with RECK mRNA-targeting siRNA. RECK expression was confirmed using real-time RT-PCR and Western blotting. Levels of matrix metalloproteinases (MMP-2 and -9) and TIMP-1 were measured by zymography and reverse zymography, respectively. Cell invasion was examined with a 3-D invasion assay. The signal cascade was investigated by cDNA microarray analysis. As expected, expression of RECK was elevated upon cDNA transfection, and diminished using siRNA. We observed elevation of MMP-2 and -9 expression and consequent 3-D cell invasion in cells under-expressing RECK. However, TIMP expression was not affected by RECK. Analysis with cDNA microarray revealed that RECK additionally upregulates growth hormone-releasing hormone receptor (GHRHR) and latrophilin 2 at the transcriptional level. Our findings collectively suggest that RECK regulates the cell signalling pathway, playing a critical neuroendocrinological role in the pituitary adenoma cell line.
Yoshida
Daizo
D
Department of Neurosurgery, Nippon Medical School, 1-1-5, Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan. dyoshida@nms.ac.jp
Nomura
Ryutaro
R
Teramoto
Akira
A
D045744:Cell Line, Tumor; D018450:Disease Progression; D004305:Dose-Response Relationship, Drug; D058851:GPI-Linked Proteins; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism; D008562:Membrane Glycoproteins; D009361:Neoplasm Invasiveness / Q000473:pathology*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010911:Pituitary Neoplasms / Q000378:metabolism* / Q000503:physiopathology*; D034741:RNA, Small Interfering / Q000494:pharmacology; D043562:Receptors, G-Protein-Coupled / Q000235:genetics / Q000378:metabolism; D018013:Receptors, Neuropeptide / Q000235:genetics / Q000378:metabolism; D018017:Receptors, Pituitary Hormone-Regulating Hormone / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology*; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism
C117618:ADGRL2 protein, human; D058851:GPI-Linked Proteins; D008562:Membrane Glycoproteins; C115460:RECK protein, human; D034741:RNA, Small Interfering; D043562:Receptors, G-Protein-Coupled; D018013:Receptors, Neuropeptide; D018017:Receptors, Pituitary Hormone-Regulating Hormone; D019715:Tissue Inhibitor of Metalloproteinase-1; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9; C048250:somatotropin releasing hormone receptor