Constitutive phosphorylation of the mTORC2/Akt/4E-BP1 pathway in newly derived canine hemangiosarcoma cell lines.
Constitutive phosphorylation of the mTORC2/Akt/4E-BP1 pathway in newly derived canine hemangiosarcoma cell lines.
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DOI：
10.1186/1746-6148-8-128
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发表时间：
2012-07-29
影响因子：
2.6
通讯作者：
Sakai H
中科院分区：
文献类型：
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作者：
Murai A;Asa SA;Kodama A;Hirata A;Yanai T;Sakai H
犬血管肉瘤（HSA）是一种恶性肿瘤，尽管经过积极治疗仍会发生转移，因此长期预后较差。磷脂酰肌醇-3 激酶/Akt/哺乳动物雷帕霉素靶点 (PI3K/Akt/mTOR) 通路参与其内皮病理学；然而，该途径如何在犬 HSA 中发挥作用仍不清楚。在这里，我们表征了源自裸鼠异种移植犬 HSA 的新犬 HSA 细胞系，并研究了这些细胞系中信号通路的失调。由3个异种移植犬HSA建立了7个犬HSA细胞系，并表现出内皮细胞（EC）的特征，即摄取乙酰化低密度脂蛋白和表达犬特异性CD31 mRNA。它们表现出 VEGF-A、bFGF、HGF、IGF-I、EGF、PDGF-B 及其受体的不同形态和 mRNA 表达水平。 1 个细胞系中这些生长因子和胎牛血清 (FBS) 刺激细胞增殖，3 个细胞系中单独使用 FBS 刺激细胞增殖。然而，在其余 3 个细胞系中，生长因子和 FBS 并未刺激细胞增殖。在 4 个细胞系中，磷酸化的 p44/42 Erk1/2 通过 FBS 刺激而增加。相比之下，在血清饥饿条件下，Akt Ser473、mTOR 复合物 1 (mTORC1) Ser2448 和真核翻译起始因子 4E 结合蛋白 1 (4E-BP1) Ser65 的磷酸化在血清饥饿条件下较高，并且在 6 个细胞系中不会因 FBS 刺激而改变，尽管这些残基在正常犬 EC 中的磷酸化增加。这表明 mTORC2/Akt/4E-BP1 通路在这 6 种犬 HSA 细胞系中被组成型激活。将细胞接种到裸鼠后，由 4 个细胞系形成犬 HSA 肿瘤，并显示出与亲本细胞系相同的 Akt 和 4E-BP1 磷酸化。我们的研究结果表明，本细胞系可能是研究 mTORC2/Akt/4E-BP1 通路在体内和体外犬 HSA 形成中的作用的有用工具。
Canine hemangiosarcoma (HSA) is a malignant tumor with poor long-term prognosis due to development of metastasis despite aggressive treatment. The phosphatidyl-inositol-3 kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway is involved in its endothelial pathologies; however, it remains unknown how this pathway plays a role in canine HSA. Here, we characterized new canine HSA cell lines derived from nude mice-xenografted canine HSAs and investigated the deregulation of the signaling pathways in these cell lines. Seven canine HSA cell lines were established from 3 xenograft canine HSAs and showed characteristics of endothelial cells (ECs), that is, uptake of acetylated low-density lipoprotein and expression of canine-specific CD31 mRNA. They showed varied morphologies and mRNA expression levels for VEGF-A, bFGF, HGF, IGF-I, EGF, PDGF-B, and their receptors. Cell proliferation was stimulated by these growth factors and fetal bovine serum (FBS) in 1 cell line and by FBS alone in 3 cell lines. However, cell proliferation was not stimulated by growth factors and FBS in the remaining 3 cell lines. Phosphorylated p44/42 Erk1/2 was increased by FBS stimulation in 4 cell lines. In contrast, phosphorylation of Akt at Ser473, mTOR complex 1 (mTORC1) at Ser2448, and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) at Ser65 was high in serum-starved condition and not altered by FBS stimulation in 6 cell lines, despite increased phosphorylation of these residues in normal canine ECs. This suggested that the mTORC2/Akt/4E-BP1 pathway was constitutively activated in these 6 canine HSA cell lines. After cell inoculation into nude mice, canine HSA tumors were formed from 4 cell lines and showed Akt and 4E-BP1 phosphorylation identical to the parental cell lines. Our findings suggest that the present cell lines may be useful tools for investigating the role of the mTORC2/Akt/4E-BP1 pathway in canine HSA formation both in vivo and in vitro.
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影响因子：
2.5
作者：
Itakura, Eijun;Yamamoto, Hidetaka;Tsuneyoshi, Masazumi
通讯作者：
Tsuneyoshi, Masazumi
影响因子：
4.8
作者：
Kroll, J;Waltenberger, J
通讯作者：
Waltenberger, J
影响因子：
4.3
作者：
Lu, JH;Zhang, JL;Patel, JM
通讯作者：
Patel, JM
影响因子：
4.8
作者：
Akhtar, N;Padilla, ML;Helfand, SC
通讯作者：
Helfand, SC
DOI：
10.3324/haematol.2009.010785
发表时间：
2010-03-01
期刊：
HAEMATOLOGICA-THE HEMATOLOGY JOURNAL
影响因子：
--
作者：
Chapuis, Nicolas;Tamburini, Jerome;Bouscary, Didier
通讯作者：
Bouscary, Didier