Down-regulation of leucine-rich repeats and immunoglobulin-like domain proteins (LRIG1-3) in HP75 pituitary adenoma cell line.
Three human leucine-rich repeats and immunoglobulin-like domains (LRIG) genes and proteins, named LRIG1-3, has been previously characterized and it was proposed that they may act as suppressors of tumor growth. The LRIG1 protein can inhibit the growth of tumors of glial cells and the down-regulation of the LRIG1 gene may be involved in the development and progression of the tumor. Real-time reverse transcription-polymerase chain reaction (RT-PCR) is a recently developed technique for quantitative assessment of specific RNA levels. In the current study, it was demonstrated that LRIG1-3 and EGFR mRNA was detected in human pituitary adenoma cell lines and a normal pituitary sample, with differences in the expression levels. Compared to the normal pituitary samples, the expression of LRIG1-3 in HP75 cell line was lower, but the expression of EGFR in HP75 cell line was higher. The results are consistent with LRIG1-3 being tumour suppressor genes, and LRIG genes decreasing the expression of EGFR. The ratio of EGFR/LRIG1 was increased at least 13-fold in HP75 cells compared with the normal pituitary cells, which was also the case for the ratio of EGFR/LRIG2 (14-fold increase in HP75) and EGFR/LRIG3 (11-fold increase in HP75). Further studies were needed to elucidate the explicit role of LRIG genes as negative regulators of oncogenesis in human pituitary adenoma.
Guo
Dongsheng
D
Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China. guodongsheng@yahoo.com
Han
Lin
L
Shu
Kai
K
Chen
Jian
J
Lei
Ting
T
D000236:Adenoma / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D003001:Cloning, Molecular; D017931:DNA Primers / Q000737:chemistry; D015342:DNA Probes / Q000737:chemistry; D018076:DNA, Complementary / Q000235:genetics; D015536:Down-Regulation; D066246:ErbB Receptors / Q000235:genetics / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases / Q000235:genetics; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D010911:Pituitary Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012333:RNA, Messenger / Q000378:metabolism; D012334:RNA, Neoplasm / Q000235:genetics / Q000302:isolation & purification; D012015:Reference Standards; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D015342:DNA Probes; D018076:DNA, Complementary; C484445:LRIG1 protein, human; C488673:LRIG2 protein, human; C496406:LRIG3 protein, human; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D066246:ErbB Receptors