ABSTRACT
PSMD10(Gankyrin), a proteasome assembly chaperone, is a widely known oncoprotein which aspects many hall mark properties of cancer. However, except proteasome assembly chaperon function its role in normal cell function remains unknown. To address this issue, we induced PSMD10(Gankyrin) overexpression in HEK293 cells and the resultant large-scale changes in gene expression profile were analyzed. We constituted networks from microarray data of these differentially expressed genes and carried out extensive topological analyses. The overrecurring yet consistent theme that appeared throughout analysis using varied network metrics is that all genes and interactions identified as important would be involved in neurogenesis and neuronal development. Intrigued we tested the possibility that PSMD10(Gankyrin) may be strongly associated with cell fate decisions that commit neural stem cells to differentiate into neurons. Overexpression of PSMD10(Gankyrin) in human neural progenitor cells facilitated neuronal differentiation via β-catenin Ngn1 pathway. Here for the first time we provide preliminary and yet compelling experimental evidence for the involvement of a potential oncoprotein – PSMD10(Gankyrin), in neuronal differentiation.
Subject(s)
Humans , HEK293 Cells , Neural Stem Cells , Neurogenesis , Neurons , Proteasome Endopeptidase Complex , Stem Cells , TranscriptomeABSTRACT
Objective To investigate the clinical significance of tumor related gene gankyrin expression in pancreatic cancer.Methods The immunohistochemical staining was performed to study the gankyrin expression in 62 pairs of pancreatic cancer and matched non-tumor tissues.The correlations ofgankyrin expression with pathological parameters and the influences on the prognosis were analyzed.Results Ggankyrin positivity in pancreatic cancer and matched non tumor tissue was 2.5％ (45/62)and 19.4％ (12/62),respectively.The positivity of gankyrin was significantly higher in pancreatic cancer compared with matched non-tumor tissues,and the differences were statistical significant (P ＜ 0.01).Gankyrin expression in pancreatic cancer tissues were significantly correlated with TNM stage,differentiation and metastasis (P ＜ 0.05),but not with age,gender or tumor location (P ＞ 0.05).The 3-year survival rates of patients with positive and negative gankyrin expression were 17.8 ％ (8/45)and 41.2％ (7/17),respectively.Patients with positive gankyrin expression had a significantly shorter survival period compared with these with negative expression in pancreatic cancer tissues (P =0.034).Conclusions Gankyrin was overexpressed in pancreatic cancer,which was correlated with poor prognosis.
ABSTRACT
Objective To evaluate the expression of Gankyrin in gastric carcinoma and preancerious lesions (including chronic atrophic gastritis and gastric epithelial dysplasia)and its clinicopathological significance.Methods Immunohistochemical assay was performed to de-tect the Gankyrin expression in 30 casess of normal gastric mucosa,60 cases of chronic atrophic gastritis,30 cases of gastric epithelial dyspla-sia,and 84 cases of gastric carcinoma.Moreover,the relationship between Gankyrin expression and clinicopathological features of gastric car-cionma was analyzed.Results Gankyrin expression was detected in normal gastric mucosa,chronic atrophic gastritis,gastric epithelial dys-plasia,and gastric carcinoma tissues in varying degrees,and the difference of Gankyrin positive rates was significant in different gastric leions mentioned above (P <0.05).The rate of Gankyrin expression in gastric carcinoma was significantly related with the clinical stage and metas-tasis.There’s no relationship between Gankyrin expression and the age,gender of patients,size,histologic grade of gastric carcinoma.Con-clusion Gankyrin participates in both the carcinogenesis and development of gastric carcinoma.Moreover,Gankyrin is a potential target for the diagnosis,prevention and treatment of gastric carcinoma.
ABSTRACT
Background:Gankyrin is an ankyrin repeat oncoprotein overexpressed and involved in the tumorigenesis and progression of various cancers. Aims:To investigate the effect and underlying mechanism of down-regulation of gankyrin expression on proliferation of gastric cancer cells. Methods:Lentivirus vector carrying gankyrin-targeted siRNA was transfected into human gastric cancer cell line MKN28. Cell proliferation,cell cycle distribution and β-catenin/ cyclin D1 signaling pathway was analyzed by MTT assay,flow cytometry and Western blotting,respectively,in gankyrin-silenced MKN28 cells and control cells. Results:The transfection efficiency of lentivirus vector was more than 90% ,and the protein expression of gankyrin in gankyrin siRNA transfected MKN28 cells was significantly repressed( P ﹤ 0. 01). Compared with cells transfected with control lentivirus and cells without transfection,MKN28 cells transfected with gankyrin siRNA showed markedly repressed cell growth after 3-day-culture;the proportion of cells in cell cycle G1 phase was significantly increased,and that in S phase was significantly decreased;down-regulated expression of β-catenin and cyclin D1 was observed(P all ﹤ 0. 01). Conclusions:Down-regulation of gankyrin expression in gastric cancer cells may induce cell cycle G1 phase arrest and inhibit cell proliferation by suppressing β-catenin/ cyclin D1 signaling pathway. Gankyrin might be a promising novel target for targeted therapy of gastric cancer.
ABSTRACT
Background and purpose: Ovarian cancer is the common gynecological cancer, and the drug resistance of anti-tumor drug was one of major reasons for therapy failure, some studies considered that there is a closed relationship between Gankyrin and drug resistance. In this study, we investigated the effects and mechanisms of Gankyrin silencing on reversing the cisplatin resistance of ovarian cancer drug-resistant SKOV3/DDP cell line. Methods:The expression of Gankyrin in SKOV3 and SKOV3/DDP cells was measured by real-time PCR assay, MTS assay was employed to determine the effect of Gankyrin on SKOV3/DDP sensitivity to cisplatin, apoptosis rate and intracellular concentration of rhodamine-123 (Rh-123) were determined by lfow cytometry, the expression of multi-drugs resistant protein MDR1, Caspase-3/8, Survivin and Bcl-2 were determined by Western blot and real-time PCR. The phosphorylation of AKT and expression of p53, NF-κB and PTEN were analyzed by Western blot assay. Results:The expression of Gankyrin was increased in SKOV3/DDP cells, Gankyrin silencing was able to increase the cisplatin sensitivity of SKOV3/DDP. Before and after gene silencing, the reverse folds (RF) to cisplatin were 1.81 and 2.45, respectively, the intracellular levels of Rh-123 were 1.73 and 2.42 fold, the apoptosis rates were 2.23 and 4.23 fold,the expressions of MDR1, Survivin and Bcl-2 were downregulated, the mRNA expressions of MDR1 were 62.8%and 21.6%, the mRNA expressions of Survivin were 24.5%and 10.3%, the mRNA expressions of Bcl-2 were 47.5%and 18.4%, the levels of Caspase-3/8, p53 and PTEN were elevated, phosphorylation of AKT and expression of NF-kB were downregulated compared with control group. Conclusion:Gankyrin silencing was able to reverse the cisplatin resistance of SKOV3/DDP cells by inhibiting the drug eflfux and promoting cell apoptosis, the PTEN/AKT/NF-κB/p53 may be the key pathway.
ABSTRACT
Objective To elucidate the expression of gankyrin in human gastric cancer cells and it's role in nimesulide induced apoptosis. Methods Four human gastric cancer cell lines including MKN28 (well differentiated), AGS (poorly differentiated), MKN45 (poorly differentiated), and SGC7901(moderately differentiated) were cultured and treated with nimesulide. Nimesulide induced growth inhibition and apoptosis of the cells were detected by methyl thiazolyl tetrazolium assay, and confirmed by flow cytometry. The expressions of gankyrin gene and protein were further assessed by real-time PCR and Western blotting. Results Gankyrin mRNA and protein were detected in all four human gastric cancer cell lines. The proliferations of AGS and SGC7901 cell lines were significantly suppressed by nimesulide in a time-dose dependent manner. When treated with 400 μmol/L of nimesulide for 48 hours, the significant apoptosis was found in AGS cells (23.30%±2.50%) and SGC7901 cells (16.80%±1.55% ) in comparison with controls (0.57%±0.19% and 0.88%± 0.17%, respectively, all P values <0.01). Apoptosis of AGS cells induced by nimesulide was accompanied by a considerably decreased gankyrin expression that was more significant at 24 hours (0.0035±0.0014) and 36 hours (0.0980±0.0160) in comparison with controls (0.4690±0.1190, all P values<0.01). Conclusion Gankyrin expresses in human gastric cancer cell lines and may be involved in nimesulide induced apoptosis of AGS cells.