title: Inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1.
abstract: The aim of this study was to explore the inhibition of subcutaneously implanted human pituitary tumor cells in nude mice by LRIG1 and its mechanism. For this study, athymic nude mice were injected with either normal pituitary tumor RC-4B/C cells or LRIG1-transfected RC-4B/C cells. We then calculated the volume inhibition rate of the tumors, as well as the apoptosis index of tumor cells and the expression of Ras, Raf, AKt, and ERK mRNA in tumor cells. Tumor cell morphological and structural changes were also observed under electron microscope. Our data showed that subcutaneous tumor growth was slowed or even halted in LRIG1-transfected tumors. The tumor volumes were significantly different between the two groups of mice (χ2 = 2.14, P < 0.05). The tumor apoptosis index was found to be 8.72% in the control group and 39.7% in LRIG1-transfected mice (χ2 = 7.59, P < 0.05). The levels of Ras, Raf, and AKt mRNA in LRIG1-transfected RC-4B/C cells were significantly reduced after transfection (P < 0.01). Transfected subcutaneous tumor cells appeared to be in early or late apoptosis under an electron microscope, while only a few subcutaneous tumor cells appeared to be undergoing apoptosis in the control group. In conclusion, the LRIG1 gene is able to inhibit proliferation and promote apoptosis in subcutaneously implanted human pituitary tumors in nude mice. The mechanism of LRIG1 may involve the inhibition of the PI3K/ Akt and Ras/Raf/ERK signal transduction pathways.
authors.affiliation: Department of Neurosurgery, The People's Hospital of Anyang City, Anyang, China.
authors.forename: X
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Neurology, The First People's Hospital of Shangqiu, Shangqiu, China.
authors.forename: X J
authors.initials: XJ
authors.lastname: He
authors.affiliation: Department of Neurosurgery, The People's Hospital of Anyang City, Anyang, China.
authors.forename: H Q
authors.initials: HQ
authors.lastname: Xu
authors.affiliation: ICU, Tangyin County People's Hospital, Anyang, China.
authors.forename: Z W
authors.initials: ZW
authors.lastname: Chen
authors.affiliation: ICU, Tangyin County People's Hospital, Anyang, China.
authors.forename: H H
authors.initials: HH
authors.lastname: Fan
mesh_terms: D000818:Animals; D017209:Apoptosis; D045744:Cell Line, Tumor; D017690:Cell Transplantation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000235:genetics / Q000378:metabolism; D015316:Genetic Therapy; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D010902:Pituitary Gland / Q000166:cytology* / Q000473:pathology; D010911:Pituitary Neoplasms / Q000628:therapy*; D051057:Proto-Oncogene Proteins c-akt / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D048490:raf Kinases / Q000235:genetics / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C484445:LRIG1 protein, human; D008562:Membrane Glycoproteins; D051057:Proto-Oncogene Proteins c-akt; D048490:raf Kinases; D048049:Extracellular Signal-Regulated MAP Kinases; D018631:ras Proteins