proteasomal degradation of PIM1 and p27KIP stabilization, thus causing a block in cell-cycle progression regardless of p53 status. iTRAQ proteomics showed that KPT-185 downregulated PIM2 irrespective of p53 status. PIM2 is known to be associated with an aggressive clinical course in B-cell lymphomas , and is involved in the regulation of mTOR complex 1. Our immunoblot data showed that KPT-185 downregulated mTORC1 downstream targets, phospho-S6K and/or phospho-4E-BP1. Gene expression profiling further showed p53-independent downregulation by KPT-185 of several factors closely associated with PIM, c-Myc, and mTOR signaling, such as cell division cycle25C , the global transcription factor pituitary tumor-transforming gene-1 , and the mTORC1 substrate serum/glucocorticoid-regulated kinase 1. The p53 status-independent transcriptional induction of PUMA by KPT-185 indicates the role of additional transcriptional factors, such as an XPO1 cargo FOXO3a that is responsible for the upregulation of PUMA , or NF-��B, whose blockade by KPT-SINEs induced p53-independent depletion of MCL cells. Of note, KPT-185 strikingly targeted cyclin D1 and its downstream signaling in MCL cells, and the blastoid-variant Z138 with high baseline expression of cyclin D1 was the most sensitive to KTP-185 among the testedMCL cell lines, suggesting that cyclin D1 is a critical target of KPT-185 for its JNJ-17203212 anti-tumor activity. KPT-185 decreased XPO1 in all tested MCL cells, which is concordant with the previous reports of MCL and lung cancer cells , in which KPT-185 induced proteasomal degradation of XPO1 protein despite its normally long half-life. In our system, KPT- 185 caused the biggest THZ1-R decline of XPO1 protein expression in JVM2 cells, which also showed the lowest sensitivity to KPT-185. Considering that SINEs irreversibly bind to the groove of XPO1 protein, which results in blockade of XPO1-directed protein export , the eventual degradation of XPO1 at longer time points might not directly affect the SINE XPO1 inhibition effects by KPT-185. Unexpectedly, pathway analysis also detected the significant upregulation of glycolysis and gluconeogenesis in KPT-185 treated MCL cells. The nuclear localiz
