TY - JOUR
T1 - Uterine leiomyosarcoma tumorigenesis in Lmp2-deficient mice
T2 - Involvement of impaired anti-oncogenic Factor IRF1
AU - Hayashi, Takuma
AU - Horiuchi, Akiko
AU - Sano, Kenji
AU - Yaegashi, Nobuo
AU - Konishi, Ikuo
PY - 2015/9/1
Y1 - 2015/9/1
N2 - Background/Aim: Uterine leiomyosarcoma (Ut- LMS) is a highly metastatic smooth muscle neoplasm. We have previously reported that low molecular mass protein2 Lmp2-deficient mice spontaneously developed Ut-LMS, which implicated this protein as an anti-oncogenic candidate. We also suggested that LMP2 may negatively regulate Ut-LMS independently of its role in the proteasome. Initially described as a transcription factor able to activate the expression of interferon-gamma (IFN-γ)-responsive genes, interferon regulatory factor-1 (IRF1) has been shown to play roles in the immune response, and tumor suppression. The aim of this study was to elucidate the molecular mechanism of sarcomagenesis of Ut-LMS using human and mouse uterine tissues. Materials and Methods: The expression of the IFN-γ signal molecules, IRF1 and -2, STAT1, and LMP2, -3, -7 and -10 were examined by western blot analysis, electrophoretic mobility shift assay and immunohistochemistry in human and mouse uterine tissues. Physiological significance of IRF1 in sarcomagenesis of Ut- LMS was demonstrated by xenograft studies. Results: In the present study, several lines of evidence indicated that although treatment with IFN-γ strongly induced the activation of STAT1 as a transcriptional activator, its target molecule, IRF1, was not clearly produced in Lmp2-deficient uterine smooth muscle cells (Ut-SMCs). Conclusion: Defective expression of IRF1 in the IFN-γ-induced signaling molecules may result in the malignant transformation of Ut- SMCs. The modulation of LMP2 may lead to new therapeutic approaches in human Ut-LMS.
AB - Background/Aim: Uterine leiomyosarcoma (Ut- LMS) is a highly metastatic smooth muscle neoplasm. We have previously reported that low molecular mass protein2 Lmp2-deficient mice spontaneously developed Ut-LMS, which implicated this protein as an anti-oncogenic candidate. We also suggested that LMP2 may negatively regulate Ut-LMS independently of its role in the proteasome. Initially described as a transcription factor able to activate the expression of interferon-gamma (IFN-γ)-responsive genes, interferon regulatory factor-1 (IRF1) has been shown to play roles in the immune response, and tumor suppression. The aim of this study was to elucidate the molecular mechanism of sarcomagenesis of Ut-LMS using human and mouse uterine tissues. Materials and Methods: The expression of the IFN-γ signal molecules, IRF1 and -2, STAT1, and LMP2, -3, -7 and -10 were examined by western blot analysis, electrophoretic mobility shift assay and immunohistochemistry in human and mouse uterine tissues. Physiological significance of IRF1 in sarcomagenesis of Ut- LMS was demonstrated by xenograft studies. Results: In the present study, several lines of evidence indicated that although treatment with IFN-γ strongly induced the activation of STAT1 as a transcriptional activator, its target molecule, IRF1, was not clearly produced in Lmp2-deficient uterine smooth muscle cells (Ut-SMCs). Conclusion: Defective expression of IRF1 in the IFN-γ-induced signaling molecules may result in the malignant transformation of Ut- SMCs. The modulation of LMP2 may lead to new therapeutic approaches in human Ut-LMS.
KW - IFN-γ
KW - IRF1
KW - LMP2
KW - Smooth muscle cell
KW - Uterine leiomyosarcoma
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M3 - Article
C2 - 26254356
AN - SCOPUS:84939634897
SN - 0250-7005
VL - 35
SP - 4665
EP - 4680
JO - Anticancer Research
JF - Anticancer Research
IS - 9
ER -
