TY - JOUR
T1 - Tofacitinib induces G1 cell-cycle arrest and inhibits tumor growth in Epstein-Barr virus-associated T and natural killer cell lymphoma cells
AU - Ando, Shotaro
AU - Kawada, Jun Ichi
AU - Watanabe, Takahiro
AU - Suzuki, Michio
AU - Sato, Yoshitaka
AU - Torii, Yuka
AU - Asai, Masato
AU - Goshima, Fumi
AU - Murata, Takayuki
AU - Shimizu, Norio
AU - Ito, Yoshinori
AU - Kimura, Hiroshi
N1 - Funding Information:
We would like to thank Yasushi Isobe (Juntendo University, Tokyo, Japan) for the NKL and TL1 cell lines. The KAI3 and KGYG1 cells were obtained from the Japanese Collection of Research Bioresources (Osaka, Japan). We also thank Dr. S. Kato and K. Kito (Department of Pathology and Laboratory Medicine, Nagoya University Hospital) for technical assistance. This study was supported by grants from the Takeda Science Foundation, the Aichi Cancer Research Foundation, and the Japan Agency for Medical Research and Development (15ek0109098).
PY - 2016
Y1 - 2016
N2 - Epstein-Barr virus (EBV) infects not only B cells, but also T cells and natural killer (NK) cells, and is associated with T or NK cell lymphoma. These lymphoid malignancies are refractory to conventional chemotherapy. We examined the activation of the JAK3/STAT5 pathway in EBV-positive and -negative B, T and NK cell lines and in cell samples from patients with EBV-associated T cell lymphoma. We then evaluated the antitumor effects of the selective JAK3 inhibitor, tofacitinib, against these cell lines in vitro and in a murine xenograft model. We found that all EBV-positive T and NK cell lines and patient samples tested displayed activation of the JAK3/STAT5 pathway. Treatment of these cell lines with tofacitinib reduced the levels of phospho-STAT5, suppressed proliferation, induced G1 cell-cycle arrest and decreased EBV LMP1 and EBNA1 expression. An EBV-negative NK cell line was also sensitive to tofacitinib, whereas an EBV-infected NK cell line was more sensitive to tofacitinib than its parental line. Tofacitinib significantly inhibited the growth of established tumors in NOG mice. These findings suggest that tofacitinib may represent a useful therapeutic agent for patients with EBV-associated T and NK cell lymphoma.
AB - Epstein-Barr virus (EBV) infects not only B cells, but also T cells and natural killer (NK) cells, and is associated with T or NK cell lymphoma. These lymphoid malignancies are refractory to conventional chemotherapy. We examined the activation of the JAK3/STAT5 pathway in EBV-positive and -negative B, T and NK cell lines and in cell samples from patients with EBV-associated T cell lymphoma. We then evaluated the antitumor effects of the selective JAK3 inhibitor, tofacitinib, against these cell lines in vitro and in a murine xenograft model. We found that all EBV-positive T and NK cell lines and patient samples tested displayed activation of the JAK3/STAT5 pathway. Treatment of these cell lines with tofacitinib reduced the levels of phospho-STAT5, suppressed proliferation, induced G1 cell-cycle arrest and decreased EBV LMP1 and EBNA1 expression. An EBV-negative NK cell line was also sensitive to tofacitinib, whereas an EBV-infected NK cell line was more sensitive to tofacitinib than its parental line. Tofacitinib significantly inhibited the growth of established tumors in NOG mice. These findings suggest that tofacitinib may represent a useful therapeutic agent for patients with EBV-associated T and NK cell lymphoma.
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U2 - 10.18632/oncotarget.12529
DO - 10.18632/oncotarget.12529
M3 - Article
C2 - 27732937
AN - SCOPUS:84998636449
VL - 7
SP - 76793
EP - 76805
JO - Oncotarget
JF - Oncotarget
SN - 1949-2553
IS - 47
ER -