BACKGROUNDTransient sublethal ischemia is known as ischemic preconditioning, which enables cells and tissues to survive subsequent prolonged lethal ischemic injury. Ischemic preconditioning exerts neuroprotection through phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Cbl-b belongs to the Casitas B-lineage lymphoma (Cbl) family, and it can regulate the cell signal transduction.The roles of ubiquitin ligase Cbl-b and PI3K/Akt pathway and the relationship between them in oxygen-glucose deprivation preconditioning (OGDPC) in PC12 cells were investigated in the present study.

METHODSOxygen and glucose deprivation (OGD) model in PC12 cells was used in the present study. The 3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, nuclear staining with Hoechst 33258, and Western blotting were applied to explore the roles of Cbl-b and PI3K/Akt pathway and the relationship between them in OGDPC in PC12 cells.

RESULTSCell viability was significantly changed by OGD and OGDPC. OGD significantly decreased cell viability compared with the control group (P < 0.05), and preconditioning could rescue this damage was demonstrated by the increase of cell viability (P < 0.05). The expression of Cbl-b was significantly increased after OGD treatment. However, the activation of Akt and GSK3β was greatly inhibited. Preconditioning could inhibit the increase of Cbl-b caused by OGD and increase the activation of Akt and GSK3β. LY294002, a specific inhibitor of PI3K, could effectively inhibit the increase of Akt and GSK3β after preconditioning treatment. It partly inhibited the decrease of Cbl-b expression after preconditioning treatment.

CONCLUSIONUbiquitin ligase Cbl-b and PI3K/Akt pathway are differently involved in OGDPC in PC12 cells.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Animals ; Cell Survival ; Glucose ; deficiency ; Ischemic Preconditioning ; Oxygen ; metabolism ; PC12 Cells ; Phosphatidylinositol 3-Kinase ; genetics ; metabolism ; Proto-Oncogene Proteins c-akt ; genetics ; metabolism ; Proto-Oncogene Proteins c-cbl ; genetics ; metabolism ; Rats ; Signal Transduction ; physiology

OBJECTIVE: Recent investigations have revealed DNA mismatch repair (MMR) gene mutations are closely related with carcinogenesis of endometrial cancer; however the impact of MMR protein expression on prognosis is not determined. Correlations between MMR-related protein expression and clinicopathological factors of endometrial cancers are analyzed in the present study. METHODS: A total of 191 endometrial cancer tissues treated between 1990 and 2007 in our hospital were enrolled. Immunoreactions for MSH2, MLH1, MSH6, and PMS2 on tissue microarray specimens and clinicopathological features were analyzed retrospectively. RESULTS: Seventy-six cases (40%) had at least one immunohistochemical alteration in MMR proteins (MMR-deficient group). There were statistically significant differences of histology, International Federation of Gynecology and Obstetrics (FIGO) stage, and histological grade between MMR-deficient group and the other cases (MMR-retained group). Response rate of first-line chemotherapy in evaluable cases was slightly higher in MMR-deficient cases (67% vs. 44%, p=0.34). MMR-deficient cases had significantly better progression-free and overall survival (OS) compared with MMR-retained cases. Multivariate analysis revealed MMR status was an independent prognostic factor for OS in endometrial cancers. CONCLUSION: MMR-related proteins expression was identified as an independent prognostic factor for OS, suggesting that MMR was a key biomarker for further investigations of endometrial cancers.
Adaptor Proteins, Signal Transducing/deficiency/metabolism ; Adenosine Triphosphatases/deficiency/metabolism ; Adult ; Aged ; Aged, 80 and over ; Chemotherapy, Adjuvant ; *DNA Mismatch Repair ; DNA Repair Enzymes/deficiency/*metabolism ; DNA-Binding Proteins/deficiency/*metabolism ; Endometrial Neoplasms/*diagnosis/drug therapy/genetics/pathology ; Female ; Humans ; Kaplan-Meier Estimate ; Middle Aged ; MutS Homolog 2 Protein/deficiency/metabolism ; Neoplasm Proteins/deficiency/metabolism ; Nuclear Proteins/deficiency/metabolism ; Prognosis ; Retrospective Studies ; Tumor Markers, Biological/*metabolism

OBJECTIVETo investigate the mRNA expressions of the TNF adapter proteins, including TNF receptor-associated death domain protein (TRADD), Fas-associated death domain protein (FADD), receptor-interacting protein 1 (RIP-1) and TNF receptor-associated factor-2 (TRAF-2) in peripheral blood mononuclear cells (PBMCs) of lupus nephritis (LN) patients of various TCM asthenia syndromes. Methods Fifty-one inpatients with LN were differentiated according to TCM syndrome differentiation, 13 cases of yin-deficiency with inner heat syndrome (A); 26 cases of both qi-yin deficiency syndrome (B), 12 cases of Pi-Shen yang-deficiency syndrome (C). Peripheral venous blood samples from the 51 LN patients and 17 healthy subjects were collected to separate PBMCs. The mRNA expressions of TNF adapter molecules (TRADD, FADD, RIP-1 and TRAF-2), as well as Caspase-3 and interleukin-1beta (IL-1beta) were analyzed by quantitative real-time PCR and the differences among them were compared.

RESULTS(1) As compared with the healthy subjects, expression of TRADD mRNA in patients of syndrome A, B and C was lowered to 0.54, 0.32, and 0.38-fold, respectively (P < 0.05, P < 0.01), showing insignificant difference among the three syndromes; (2) FADD mRNA lowered to 0.79, 0.62, and 0.72-fold respectively, only with significance shown in syndrome B (P < 0.05); (3) RIP-1 mRNA lowered to 0.79, 0.50, and 0.60-fold respectively with significance shown in syndrome B and C (P < 0.01, P < 0.05), and insignificant difference was shown among the three syndromes; (4) TRAF-2 lowered to 0.70, 0.52, and 0.50-fold respectively (P < 0.01, P < 0.01, P = 0.07), significance shown in syndrome B and C (P < 0.01), but with insignificant difference among the three; (5) Caspase-3 elevated in all patients of the three syndromes (all P < 0.01); (6) IL-1beta in syndrome A was apparently lower ed to the normal range and also lower than that in the other two syndromes (both P < 0.05).

CONCLUSIONSExpressions of TRADD, FADD, RIP-1 and TRAF-2 mRNA decreased in all the patients of various TCM asthenia syndromes, the decrement in patients of syndrome B and C was lesser than that in syndrome A. These abnormal low expressions of signal proteins might be the substantial bases for asthenia syndromes of LN patients, and the apoptotic signal mediated by them may involve in the formation of asthenia syndrome in LN.

Adaptor Proteins, Signal Transducing ; genetics ; metabolism ; Adolescent ; Adult ; Case-Control Studies ; Child ; Fas-Associated Death Domain Protein ; genetics ; metabolism ; Female ; Humans ; Leukocytes, Mononuclear ; metabolism ; Lupus Nephritis ; blood ; Male ; Medicine, Chinese Traditional ; Middle Aged ; RNA, Messenger ; genetics ; metabolism ; Receptor-Interacting Protein Serine-Threonine Kinases ; genetics ; metabolism ; TNF Receptor-Associated Death Domain Protein ; genetics ; metabolism ; TNF Receptor-Associated Factor 2 ; genetics ; metabolism ; Tumor Necrosis Factor-alpha ; blood ; metabolism ; Yang Deficiency ; blood ; Yin Deficiency ; blood ; Young Adult