In Sung Song1, Soo Young Jun2, Hee-Jun Na3, Hyun-Taek Kim4, So Young Jung5, Ga Hee Ha5, Young-Ho Park6, Liang Zhe Long7, Dae-Yeul Yu6, Jin-Man Kim7, Joo Heon Kim8, Jeong-Heon Ko9, Cheol-Hee Kim10, Nam-Soon Kim11. 1. Medical Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea; Cardiovascular and Metabolic Disease Center, Inje University, Busan, South Korea. 2. Medical Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea; Department of Functional Genomics, University of Science and Technology, Daejeon, South Korea. 3. Department of Functional Genomics, University of Science and Technology, Daejeon, South Korea; Renal Division, Brigham and Women's Hospital, Department of Medicine, Harvard Medical School, Boston, Massachusetts. 4. Department of Biology, Chungnam National University, Daejeon, South Korea. 5. Medical Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea. 6. Department of Functional Genomics, University of Science and Technology, Daejeon, South Korea; Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea. 7. Department of Pathology, School of Medicine, Chungnam National University, Daejeon, South Korea. 8. Department of Pathology, Eulji University School of Medicine, Daejeon, South Korea. 9. Daejeon-KRIBB-FHCRC Research Cooperation Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea. 10. Department of Biology, Chungnam National University, Daejeon, South Korea. Electronic address: zebrakim@cnu.ac.kr. 11. Medical Genomics Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, South Korea; Department of Functional Genomics, University of Science and Technology, Daejeon, South Korea. Electronic address: nskim37@kribb.re.kr.
Abstract
BACKGROUND & AIMS: The TOR signaling pathway regulator-like (TIPRL) protein, the mammalian ortholog of yeast TIP41, was identified in an expression profiling screen for factors that regulate human liver carcinogenesis. We investigated the role of human TIPRL protein in hepatocellular carcinoma (HCC). METHODS: We measured the level of TIPRL in HCC and adjacent nontumor tissues from patients. We used small interfering RNAs and zebrafish to study the function of TIPRL. We used annexin V propidium iodide staining and immunoblot analyses to measure apoptosis and activation of apoptotic signaling pathways. We used confocal microscopy, coimmunoprecipitation, and glutathione-S transferase pull-down analyses to determine interactions among mitogen-activated protein kinase kinase 7 (MKK7 or MAP2K7), TIPRL, and the protein phosphatase type 2A (PP2Ac). We studied the effects of TIPRL in tumor xenografts in mice. RESULTS: Levels of TIPRL were higher in HCC tissues and cell lines than nontumor tissues and primary hepatocytes. Knockdown of tiprl expression in zebrafish led to large amounts of apoptosis throughout the embryos. Incubation of HCC cells, but not primary human hepatocytes, with small interfering RNA against TIPRL (siTIPRL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) caused prolonged activation (phosphorylation) of MKK7 and c-Jun N-terminal kinase (JNK) and led to apoptosis, indicated by cleavage of procaspase-8,-3 and of poly-(adenosine diphosphate-ribose) polymerase. TIPRL bound to MKK7 and PP2Ac and promoted the interaction between MKK7 and PP2Ac. In mice, injection of HCC xenograft tumors with siTIPRL and TRAIL led to tumor apoptosis and regression. CONCLUSIONS: TIPRL is highly up-regulated in human HCC samples and cell lines, compared with noncancerous liver tissues. TIPRL prevents prolonged activation of MKK7 and JNK and TRAIL-induced apoptosis by mediating the interaction between MKK7 and PP2Ac.
BACKGROUND & AIMS: The TOR signaling pathway regulator-like (TIPRL) protein, the mammalian ortholog of yeast TIP41, was identified in an expression profiling screen for factors that regulate humanliver carcinogenesis. We investigated the role of humanTIPRL protein in hepatocellular carcinoma (HCC). METHODS: We measured the level of TIPRL in HCC and adjacent nontumor tissues from patients. We used small interfering RNAs and zebrafish to study the function of TIPRL. We used annexin V propidium iodide staining and immunoblot analyses to measure apoptosis and activation of apoptotic signaling pathways. We used confocal microscopy, coimmunoprecipitation, and glutathione-S transferase pull-down analyses to determine interactions among mitogen-activated protein kinase kinase 7 (MKK7 or MAP2K7), TIPRL, and the protein phosphatase type 2A (PP2Ac). We studied the effects of TIPRL in tumor xenografts in mice. RESULTS: Levels of TIPRL were higher in HCC tissues and cell lines than nontumor tissues and primary hepatocytes. Knockdown of tiprl expression in zebrafish led to large amounts of apoptosis throughout the embryos. Incubation of HCC cells, but not primary human hepatocytes, with small interfering RNA against TIPRL (siTIPRL) and tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) caused prolonged activation (phosphorylation) of MKK7 and c-Jun N-terminal kinase (JNK) and led to apoptosis, indicated by cleavage of procaspase-8,-3 and of poly-(adenosine diphosphate-ribose) polymerase. TIPRL bound to MKK7 and PP2Ac and promoted the interaction between MKK7 and PP2Ac. In mice, injection of HCC xenograft tumors with siTIPRL and TRAIL led to tumor apoptosis and regression. CONCLUSIONS:TIPRL is highly up-regulated in human HCC samples and cell lines, compared with noncancerous liver tissues. TIPRL prevents prolonged activation of MKK7 and JNK and TRAIL-induced apoptosis by mediating the interaction between MKK7 and PP2Ac.
Authors: Souvik Ghosh; Meric Ataman; Maciej Bak; Anastasiya Börsch; Alexander Schmidt; Katarzyna Buczak; Georges Martin; Beatrice Dimitriades; Christina J Herrmann; Alexander Kanitz; Mihaela Zavolan Journal: Nucleic Acids Res Date: 2022-04-08 Impact factor: 16.971
Authors: Ioannis Gkouveris; Nikolaos Nikitakis; Maria Karanikou; George Rassidakis; Alexandra Sklavounou Journal: Oncol Lett Date: 2016-05-24 Impact factor: 2.967