Lipid second messengers,particularly phosphoinositides,play a pivotal role in several cell signaling networks.Specific inositol lipids such as PtdIns(3,4)P_(2) and PtdIns(3,4,5)P_(3) which are generated by phosphoinositide 3-kinases(PI3Ks) are specific activators to the serine/threonine protein kinase Akt that have been implicated in a plethora of cell functions.Studies show that Akt stimulates cell proliferation and suppresses apoptosis,and is implicated in cancer progression.Many evidences have highlighted the presence of an autonomous nuclear inositol lipid metabolism,and suggest that lipid molecules are important components of signaling pathways in the nucleus.

Objective To study whether stem cell antigen-positive(Sca-1 + )cells from fetal liver can differentiate into neural cells. Methods Sca-1+ cells from male fetal liver were isolated with a magnetic cell sorting kit and transplanted into lethally irradiated female mice (2?103 cells/mouse). The donor cells and their characteristics in recipient brains were identified and detected by FISH and immunohistochemistry double-staining analysis at 2, 4, 6 months after transplantation. Results There existed many male cells in brains of female recipients, including white and gray matters, for brain, midbrain, the ependyma of the ventricular system, and the choroid plexus of the lateral ventri cle. Immunochemistry revealed that the Y chromosome-positive cells expressed many neural specific markers, including Neu N, TuJ-1 , NF-M, GFAP and so on. Statistic analysis showed that ratio of Y chromosome positive cells in brain was (4. 5 ? 0. 5) %, ratio of both Y chromosome and NeuN posi live cells (1. 2 ? 0. 3) %. ratio of both Y chromosome and GFAP positive cells (1. 0 ? 0. 2) %. There was no difference between the ratios of Y chromosome-positive cells in brains 2,4, and 6 month after transplantation. Conclusion Sca-1 + cells from fetal liver, the most of which are regarded as hemato-poietic stem cells, can differentiate into neural cells and astrocytes in the brains of adult mice and survive more than 6 months.

Embryonic stem cells (ESC) can develop into neural cells both in vivo and in vitro, this may elucidate the mechanism of nervous system development. ESC-derived uncommitted neural precursors or progenitors may play a role in future transplantation therapies for injury or deregeneration of nervous system. This article reviews embryonic stem cells differentiating into neural cells and characteristics of its gene expression.

AIM: To study whether Sca-1 + cells from fetal liver can be induced to differentiate into neuronal cells in vitro. METHODS: Sca-1 + cells from 14 5-days-old murine fetal liver were isolated with a magnetic cell sorting kit, and were cultured in Dulbecco's modified Eagle's medium (DMEM)/F12 supplemented with 10% fetal bovine serum (FBS), and passaged at a ratio of 1∶3 when cells reached more than 80% confluence. The 5 passage cells were induced by 10 -3 mol/L ?-mercaptoethanol (?-ME) and 5 ?10 -7 mol/L all-trans-retinoic acid (RA) for 24 hours, and then incubated in serum-free medium for 5 hours to 5 days. The characteristics of treated cells were assayed by immunocytochemistry staining analysis at 5 hours, or 5 days.RESULTS: Cells treated with ?-ME and RA exhibited neuronal phenotype and expressed neuron-specific protein such as neuron-specific nuclear protein (NeuN), neuronfilament-M, and neuron-specific tubulin-1 (TuJ-1) but not tau, MAP-2, or the astrocyte-specific marker glial fibrillary acidic protein (GFAP).CONCLUSION: Sca-1 + cells from fetal liver, of which most are regarded as hematopoietic stem cells, could differentiate into early immature neuronal cells in vitro . These findings suggest that Sca-1 + cells from fetal liver may be an alternative source in cell therapy and gene therapy of neural dysfunction.

AIM: To determine whether Sca-1~+ cells from fetal liver can differentiate into neural cells. METHODS: The sex of 14.5-day-old murine fetuses was determined by PCR analysis of sry gene, and Sca-1~+ cells from male fetal liver were isolated with a magnetic cell sorting kit, 2?10~3 of which were then transplanted into lethally irradiated female mice. The donor cells and their characteristics in recipient brains were identified and detected by FISH and immunohistochemistry double-staining analysis at 60, 120, 180 days after transplantation. RESULTS: There existed many male cells in brains of female recipients, some of them express neuron-specific nuclear protein (NeuN), and some of them express the astrocyte-specific marker, i.e. glial fibrillary acidic protein (GFAP). CONCLUSION: Sca-1~+ cells from fetal liver, which contain hematopoietic stem cells, can differentiate into neuronal cells and astrocytes in the brains of adult mice.

Objective:To investigate potency of mouse fetal liver mesenchymal cells differentiating into neural cells in vitro .Methods: Sterile cells from 14.5 day old mouse fetal liver were cultured in DMEM/HEPES/F12 supplemented with 20%FCS and adherent cells were acquired after discarding nonadherent cells. The 5th passage cells were induced by ? mercaptoethanol (? ME) and all trans retinoic acid (ATRA). The characteristics of treated cells were assayed by immunocytochemistry staining and semi quantitative RT PCR method on 5 h and 5 d after induction. Results: After induction by ? ME and ATRA, approximately 80% of the cells exhibited typical neuronal morphology;most cells expressed neuronal phenotype such as neuron specific nuclear protein(NeuN), neuron specific tubulin Ⅲ(TuJ 1), neurofilament M(NF M),and neuron specific enolase(NSE).However, microtubule associated protein tau(Tau 1)and microtubule associated protein 2 (MAP 2) as indicators of mature neuronal phenotype were undetectable. Semi quantitative RT PCR showed increased mRNA expression of brain factor 1(BF 1), brain 3(Brn 3), and neurofilament L(NF L) in treated cells versus untreated cells ( P

Objective:To investigate the effects of Bcl-2 shRNA on the growth of liver carcinoma cell line BEL-7402 and colorectal carcinoma cell line Caco2.Methods: Bcl-2 shRNA was cloned into Pgenesil-1 plasmid labeled with fluorescent protein and the product was transfected into BEL-7402 and Caco2 cells with Lipofectamine 2000.The study also included shRNA as negative control,Pgenesil-1,Lipofectamine and blank control groups.Transfected cells were visualized by inverted fluorescent microscope and then assayed by flow cytometry.The expression levels of Bcl-2 protein were assayed by Western-blot and cell proliferation was measured by MTT method.Results: There was no difference in transfection rate among cells in Bcl-2 shRNA,shRNA and Pgenesil-1 vector groups.Western-blot assay showed that the expression levels of Bcl-2 protein in BEL-7402 and Caco2 cells were significantly decreased in Bcl-2 shRNA group compared with those in other 4 groups(P

Objective:To study the mechanism of tretinoin-induced neural differentiation in fetal liver CD34+ cells in vitro. Methods :CD34+ cells from fetal liver were isolated with a magnetic cell sorting kit and were cultured. Cells pretreated with or without protein kinase C(PKC) inhibitor chelerythrine chloride(3 ?mol/L) were induced by 5?10-7mol/L tretinoin for 24 h, and then incubated in serum-free medium. Expressions of genes in treated cells were assayed by Western blotting and RT-PCR. Results: Tretinoin significantly promoted expression of neural specific genes such as Nestin, neuron-specific nuclear protein (NeuN) , neuron-specific neuronfilament-M (NF-M) , and MAP-2 in fetal liver CD34+ cells, with Nestin increased by 4. 09 folds, NeuN by 5. 12 folds, and NF-M by 7. 27 folds (all P

AIM: To study the mechanism of butylated hydroxyanisole-induced neural differentiation of fetal liver Sca-1~+ cells in vitro. METHODS: Sca-1~+ cells from 14.5-day-old mouse fetal liver were isolated with a magnetic cell sorting kit. Cultured cells pretreated with or without extracellular signal-regulated kinase (MEK1) inhibitor, PD98059, were induced by 200 ?mol/L butylated hydroxyanisole (BHA) for 24 hours, and then incubated in serum-free medium. Expression of genes in treated or untreated cells were assayed by Western blotting and RT-PCR. RESULTS: There was low level of neuronfilament-L (NF-L) and brain factor-1 (BF-1) in fetal liver Sca-1~+ cells, but no neuronfilament-H (NF-H) and tyrosine hydroxylase (TH) was observed. BHA significantly promoted the expression of neuron-specific NF-L, NF-H, BF-1, and TH in fetal liver Sca-1~+ cells. NF-L, NF-H, BF-1 and TH increased by 6.32 fold, 2.73 fold, 3.37 fold and 2.68 fold, respectively (all P

Objective To analyze mutations in the Wilms tumor gene (WT1) in Ieukemogenesis.Methods WT1 gene in peripheral blood was determined by PRC-SSCP technique,in 32 cases of acute leukemia,included 9 cases of acute granulocytic leukemia,8 cases of chronic granulocytic leukemia(mean age-33 years) and 16 specimens of normal subjects were also detected.Results Mutations in the WT1 gene in 3 of 32 leukemias were found .WT1 mutations were found in 11% of cases of acute lymphoblastic leukemia and in 13% of cases of acute myeloid leukemia,in which they were associtated with a poor response to chemotherapy.Conclusions The mutations in Wilms tumor gene WT1 are associated with leukemogenesis and its therapy,which WT1 transcripts may prove a significant tumor marker, as a MRD monitor in evaluating remission status and early relapse,and may be useful in prognosis of acute leukemia.