ABSTRACT
Dysregulated nuclear-cytoplasmic trafficking has been shown to play a role in oncogenesis in several types of solid tumors and hematological malignancies. Exportin 1 (XPO1) is responsible for the nuclear export of several proteins and RNA species, mainly tumor suppressors. KPT-330, a small molecule inhibitor of XPO1, is approved for treating relapsed multiple myeloma and diffuse large B-cell lymphoma. Cutaneous T-cell lymphoma (CTCL) is an extranodal non-Hodgkin lymphoma with an adverse prognosis and limited treatment options in advanced stages. The effect of therapeutically targeting XPO1 with KPT-330 in CTCL has not been established. We report that XPO1 expression is upregulated in CTCL cells. KPT-330 reduces cell proliferation, induces G1 cell cycle arrest and apoptosis. RNA-sequencing was used to explore the underlying mechanisms. Genes associated with the cell cycle and the p53 pathway were significantly enriched with KPT-330 treatment. KPT-330 suppressed XPO1 expression, upregulated p53, p21WAF1/Cip1, and p27Kip1 and their nuclear localization, and downregulated anti-apoptotic protein (Survivin). The in vivo efficacy of KPT-330 was investigated using a bioluminescent xenograft mouse model of CTCL. KPT-330 blocked tumor growth and prolonged survival (p < 0.0002) compared to controls. These findings support investigating the use of KPT-330 and next-generation XPO1 inhibitors in CTCL.
Subject(s)
Apoptosis , Cyclin-Dependent Kinase Inhibitor p21 , Cyclin-Dependent Kinase Inhibitor p27 , Exportin 1 Protein , Karyopherins , Lymphoma, T-Cell, Cutaneous , Receptors, Cytoplasmic and Nuclear , Triazoles , Tumor Suppressor Protein p53 , Humans , Receptors, Cytoplasmic and Nuclear/metabolism , Receptors, Cytoplasmic and Nuclear/antagonists & inhibitors , Lymphoma, T-Cell, Cutaneous/drug therapy , Lymphoma, T-Cell, Cutaneous/pathology , Lymphoma, T-Cell, Cutaneous/metabolism , Lymphoma, T-Cell, Cutaneous/genetics , Apoptosis/drug effects , Animals , Cyclin-Dependent Kinase Inhibitor p21/metabolism , Cyclin-Dependent Kinase Inhibitor p21/genetics , Cyclin-Dependent Kinase Inhibitor p27/metabolism , Cyclin-Dependent Kinase Inhibitor p27/genetics , Tumor Suppressor Protein p53/metabolism , Tumor Suppressor Protein p53/genetics , Karyopherins/metabolism , Karyopherins/antagonists & inhibitors , Mice , Cell Line, Tumor , Triazoles/pharmacology , Cell Proliferation/drug effects , Hydrazines/pharmacology , Hydrazines/therapeutic use , Xenograft Model Antitumor Assays , Signal Transduction/drug effects , Gene Expression Regulation, Neoplastic/drug effectsABSTRACT
Large granular lymphocytic leukemia (LGLL) is a lymphoproliferative disorder of older adults characterized by the clonal expansion of cytotoxic T/natural killer cells due to constitutive pro-survival signaling. In recent years, it has become clear that cytokines and their receptors are aberrantly expressed in LGLL cells. The exact initiation process of LGLL is unknown, although several cytokine-driven mechanisms have emerged. Elevated levels of several cytokines, including interleukin-15 (IL-15) and platelet-derived growth factor (PDGF), have been described in LGLL patients. Evidence from humans and animal models has shown that cytokines may also contribute to the co-occurrence of a wide range of autoimmune diseases seen in patients with LGLL. The goal of this review is to provide a comprehensive analysis of the link between cytokines and pro-survival signaling in LGLL and to discuss the various strategies and research approaches that are being utilized to study this link. This review will also highlight the importance of cytokine-targeted therapeutics in the treatment of LGLL.
ABSTRACT
The RNA species SHR1 reacts with biocytin (epsilon-biotinoyl-L-lysine) in the presence of Ni(2+) or Pt(2+) to produce a metal-bridged complex that migrates more slowly than unreacted RNA in the presence of streptavidin (StrAv) on denaturing polyacrylamide gels. Mapping of reverse transcription pause sites identified G79 as a reactive nucleotide. G79 is near the 3' end of a 37 nucleotide core motif that is nearly as reactive as SHR1. SHR1 reacts with biocytin in the presence of Pt(2+) to yield a product that comigrates with the Ni(2+) product but that is much more stable, suggesting that the metal ion used in the reaction is present in the product, possibly linking the RNA to the amino acid. In support of this model, SHR1 shows a strong affinity for Ni(2+) in immobilized metal ion chromatography.
Subject(s)
Amino Acids/chemistry , Nickel/chemistry , RNA/chemistry , Base Sequence , DNA Primers , Nucleic Acid ConformationABSTRACT
OBJECTIVE: To use DNA microarray technology to examine differential gene expression in uterine endometrium versus endometriosis implants. DESIGN: Pilot study. SETTING: Volunteers in an academic research environment. PATIENT(S): Premenopausal women scheduled for surgery for suspected endometriosis. INTERVENTION(S): Surgical excision of endometriosis tissue and uterine endometrial biopsy. MAIN OUTCOME MEASURE(S): Gene expression. RESULT(S): The expression of eight genes from a total of 4,133 genes on the DNA microarray was increased in endometriosis implants compared with uterine endometrium. The eight genes were beta-actin, alpha-2 actin, vimentin, 40S ribosomal protein S23, Ig-lambda light chain, Ig germline H chain G-E-A region gamma-2 constant region gene, major histocompatibility complex class 1,C, and complement component 1 S subcomponent. CONCLUSION(S): The data demonstrate that the DNA microarray is an effective tool for the identification of differentially expressed genes between uterine and ectopic endometrium; further study of the genes identified herein will expand our understanding of the nature of endometriosis and assist in the eventual development of new treatments for endometriosis.
