ObjectiveTo examine the association between fragile X mental retardation protein (FMRP) expression and astrocytoma characteristics.MethodsPathologic grade and expressions of glial fibrillary acidic protein (GFAP), Ki67 (proliferation marker), and FMRP were determined in astrocytoma specimens from 74 patients. Kaplan-Meier survival analysis was undertaken. Pathologic grade and protein levels of FMRP were determined in 24 additional patients with astrocytoma and 6 controls (cerebral trauma). In cultured U251 and U87 cell lines, the effects of FMRP knock-down on cell proliferation, AKT/mTOR/GSK-3β and MEK/ERK signaling were studied. The effects of FMRP knock-down on the volumes and weights of U251 cell-derived orthotopic tumors in mice were investigated.ResultsIn patients, FMRP expression was increased in grade IV (5.1-fold, P<0.01) and grade III (3.2-fold, P<0.05) astrocytoma, compared with controls. FMRP and Ki67 expressions were positively correlated (R2=0.877, P<0.001). Up-regulation of FMRP was associated with poorer survival among patients with FMRP integrated optical density >30 (P<0.01). In astrocytoma cell lines, FMRP knock-down slowed proliferation (P<0.05), inhibited total MEK levels P<0.05, and reduced phosphorylation of MEK (Ser217/221) and ERK (Thr202/Tyr204) (P<0.05). In mice with orthotopic tumors, FMRP knock-down decreased FMRP and Ki67 expressions, and reduced tumor volume and weight (36.3% or 61.5% on day 15, both P<0.01). Also, phosphorylation of MEK (Ser217/221) and ERK (Thr202/Tyr204), and total MEK in xenografts were decreased in sh-FMRP xenografts compared with non-transfected ones (all P<0.05).ConclusionEnhanced FMRP expression in astrocytoma may promote proliferation through activation of MEK/ERK signaling.

The aim of the present study was to analyze the association between the transcription factor forkhead box P3 (FOXP3) and diffuse large B-cell lymphoma (DLBCL), and investigate the effect of microRNA-155 (miR-155) on the generation and development of FOXP3 in DLBCL. The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) technique was used to determine the expression of FOXP3 in the human DLBCL cell lines Ly1, Ly8 and Ly10, and in normal B cells. An immunohistochemical method was used to determine FOXP3 expression in 60 DLBCL tumor and adjacent tissues, and a retrospective analysis of FOXP3 expression in tumor tissues and clinical data was performed. The lentiviral transfection technique was used to silence the miR-155 gene in mouse A20 cells to analyze the influence of miR-155 on FOXP3 in DLBCL. The A20 cell line with a silenced miR-155 gene was used to perform a tumorigenicity assay in BALB/c mice, and to compare the tumorigenicity rate and the tumor growth rate. The results identified that the expression of the transcription factor FOXP3 in the human DLBCL cell lines was increased compared with normal B cells; FOXP3 in human DLBCL tumor issues was increased compared with the tumor-adjacent tissue, and the increased expression of FOXP3 was identified as an indicator of poor prognosis of patients with DLBCL in the middle and late period; FOXP3 level decreased subsequent to silencing miR-155 in A20 cells; A20 cells with the low-expression miR-155 gene were used to determine the tumorigenicity in BALB/c mice and it was identified that the tumorigenicity of the low-expression miR-155 gene group was decreased compared with the untransfected group. Therefore, miR-155 may be a regulatory factor of FOXP3, and miR-155 may be associated with the metastasis and prognosis of patients with DLBCL.

Heat shock proteins (HSPs) are molecular chaperones that are consistently increased to help cells survive under conditions of stress. As a member of the Hsps, Hsp90 is involved in protein post‑translational maturation and disposition. This protein is ubiquitously expressed in normal cells. However, in cancer cells and particularly in hematological malignancies, Hsp90 is unexpectedly abundant to maintain levels of proteins vital for cancer pathology. Hsp90 inhibitors can target the ATP domain of Hsp90 and prohibit its exchange of ADP for ATP, leading to the degradation of client proteins and disruption of signaling cascades. Concomitantly, Hsp90 inhibitors induce tumor cell apoptosis, promote cell cycle arrest and abrogate microenvironment‑derived cytoprotection. Geldanamycin, a benzoquinone antineoplastic antibiotic isolated from the bacterium Streptomyces hygroscopicus, and its derivative, 17‑AAG, were first developed as Hsp90 inhibitors and exhibited effective anticancer potency. Whereas, severe side effects and low solubility restricted their application at the clinical level, BIIB021, a novel and fully synthetic inhibitor of Hsp90, is water soluble and well‑tolerated. Beyond degrading oncogenic protein, BIIB021 can overcome multidrug resistance and potentiate the effects of other therapeutics. phase I/II trials have been conducted to evaluate the dosing schedules and activity of this agent. The present review focuses on the antitumor profile of BIIB021. Furthermore, given the promising efficacy of BIIB021 in leukemia and lymphoma, this review also discusses current research concerning the treatment of hematologic malignancies by targeting Hsp90.

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Activation-induced cytidine deaminase (AID) is one kind of the mutant enzymes, which target regulating the immunoglobulin (Ig) gene in Burkitt’s lymphoma to initiate class switch recombination (CSR), resulting in c-Myc chromosomal translocation. However, it is not clear that whether AID induces c-Myc/IgH translocation in double-hit lymphoma (DHL) with c-Myc gene translocation. In this study, the AID in DHL tissues and classical diffuse large b-cell lymphoma (DLBCL) tissues were compared. The results suggested that AID is of important value in predicting DHL, stronger CSR of AID was observed in DHL patients, which exhibited AID overexpression and c-Myc gene translocation of DHL after CSR induction. It is concluded that AID directly induces CSR in DHL and may result in c-Myc gene translocation. Targeting AID may be a good treatment regimen for DHL.