Nuclear Cloning of Embryonal Carcinoma Cells Blelloch, Robert H.; Hochedlinger, Konrad; Yamada, Yasuhiro ...
Proceedings of the National Academy of Sciences - PNAS,
09/2004, Letnik:
101, Številka:
39
Journal Article
Recenzirano
Odprti dostop
Embryonal carcinoma (EC) cells have served as a model to study the relationship between cancer and cellular differentiation given their potential to produce tumors and, to varying degrees, ...participate in embryonic development. Here, nuclear transplantation was used to assess the extent to which the tumorigenic and developmental potential of EC cells is governed by epigenetic as opposed to genetic alterations. Nuclei from three independent mouse EC cell lines (F9, P19, and METT-1) with differing developmental and tumorigenic potentials all were able to direct early embryo development, producing morphologically normal blastocysts that gave rise to nuclear transfer (NT)-derived embryonic stem (ES) cell lines at a high efficiency. However, when tested for tumor or chimera formation, the resulting NT ES cells displayed an identical potential as their respective donor EC cells, in stark contrast to previously reported NT ES cells derived from transfer of untransformed cells. Consistent with this finding, comparative genomic hybridization identified previously undescribed genetic lesions in the EC cell lines. Therefore, nonreprogrammable genetic modifications within EC nuclei define the developmental and tumorigenic potential of resulting NT ES cells. Our findings support the notion that cancer results from the deregulation of stem cells and further suggest that the genetics of ECs will reveal genes involved in stem cell self-renewal and pluripotency.
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Many natural anti-DNA antibodies (Abs) have the ability to translocate across the plasma membrane and localize in the nucleus of mammalian cells, frequently leading to cytotoxicity to cells. ...Herein, we report detailed intracellular trafficking routes and cytotoxicity in HeLa cells for a single chain variable fragment (scFv) Ab, 3D8, which is an anti-DNA Ab capable of hydrolyzing both DNA and RNA. The intracellular penetration of 3D8 scFv occurred by caveolae/lipid raft endocytosis. The time-course chasing experiments revealed that 3D8 scFv escaped directly from the caveosome into the cytosol and remained in the cytosol without further trafficking into endosomes, lysosomes, endoplasmic reticulum, Golgi, or nucleus. The cytosolically localized 3D8 scFv maintained its nuclease activity to hydrolyze cellular RNAs, mainly mRNAs, eventually triggering apoptotic cell death. Our results demonstrate that 3D8 scFv has a unique intracellular trafficking route of localizing in the cytosol, thereby exhibiting cytotoxicity due to its nuclease activity.
ABSTRACT
Response surface methodology was used to optimize the lipase‐catalyzed transesterification reaction between conjugated linoleic acid (CLA) and soybean oil. On the basis of the model, ...structured lipids (SLs) were synthesized from CLA and soybean oil or sunflower oil. CLA was incorporated in SL‐soybean (24.4 mol%) and SL‐sunflower (23.1 mol%), respectively. Isomerization to trans, trans CLA was observed during the reaction. Throughout the oxidation study, all SLs showed higher peroxide values (POVs), p‐anisidine values, and 2‐thiobarbituric acid‐reactive substance values than their counterparts. Rosemary extracts with a different amount (100 to 300 ppm) could effectively reduce oxidation in soybean oil, sunflower oil, and their SLs.
Galectin-3 is a member of a growing family of animal beta-galactoside-binding proteins shown to be involved in cell growth, differentiation, apoptosis resistance, and tumor progression. In the ...present study, we investigated whether galectin-3 can protect against apoptosis induced by the loss of cell anchorage (anoikis). Because studies suggest that cellular sensitivity to anoikis is associated with cell cycle regulation, we examined the role of galectin-3 on cell cycle regulation. Although BT549 cells (human breast epithelial cells) undergo anoikis, galectin-3-overexpressing BT549 cells respond to the loss of cell adhesion by inducing G1 arrest without detectable cell death. Galectin-3-mediated G1 arrest involves down-regulation of G1-S cyclin levels (cyclin E and cyclin A) and up-regulation of their inhibitory protein levels (p21(WAF1/CIP1) and p27KIP1). After the loss of cell anchorage, Rb protein becomes hypophosphorylated in galectin-3-overexpressing cells, as predicted from the flow cytometric analysis and immunoblot analysis of cyclins and their inhibitors. Interestingly, galectin-3 induces cyclin D1 expression (an early G1 cyclin) and its associated kinase activity in the absence of cell anchorage. On the basis of these results, we propose that galectin-3 inhibition of anoikis involves cell cycle arrest at an anoikis-insensitive point (late G1) through modulation of gene expression and activities of cell cycle regulators. The present study suggests that galectin-3 may be a critical determinant for anchorage-independent cell survival of disseminating cancer cells in the circulation during metastasis.
Background and aims
The incidence of double primary malignancies (DPM) is known to be higher in colorectal cancer patients than the general population. And, the role of microsatellite instability ...(MSI) in DPM has been previously studied. We evaluated the clinical features and association between MSI and colorectal cancer patients with DPM.
Materials and methods
From September 1994 to May 2004, we reviewed 2,301 colorectal cancer patients with regard to secondary primary malignancies. A subgroup analysis was performed for MSI after January 2003.
Results
One hundred forty-five patients (6.3%) had a DPM identified. In DPM group, 57 patients had a synchronous DPM (39.3%), and 88 patients had a metachronous malignancy (60.7%). Male gender (
p
< 0.001) and colon cancer (
p
< 0.001) were the factors related with the development of the DPM. Most of the second malignancies occurred within 3 years after the primary operation. The common second malignancies were stomach (58 patients, 40%) and lung (21 patients, 14.5%). In the subgroup analysis, there was a higher frequency of DPM in the MSI group when compared to the microsatellite stable group (
p
= 0.021).
Conclusions
The careful pre- and postoperative evaluation should be paid for detecting DPM as well as for detecting recurrence in colorectal cancer patients. The results of this study suggest that MSI might be a useful marker for the detection of DPM in colorectal cancer patients.
Alfentanil (ALF) is a validated probe for hepatic, first‐pass, and intestinal cytochrome P450 (CYP) 3A activity, using plasma clearances, single‐point concentrations, and noninvasive pupil diameter ...change (miosis). Assessing intravenous (i.v.) and oral drug disposition typically requires separate dosing. This investigation evaluated concurrent administration of oral deuterated and i.v. unlabeled ALF to assess both intestinal and hepatic CYP3A, and compare sequential and simultaneous dosing. ALF disposition was evaluated after strong hepatic and/or intestinal CYP3A induction and inhibition by rifampin, ketoconazole, and grapefruit juice. Using plasma ALF concentrations and area under the curve (AUC), clearance, or single‐point concentrations, both simultaneous and sequential dosing provided equivalent results and detected hepatic and intestinal CYP3A induction and inhibition. Miosis better detected CYP3A modulation with sequential vs. simultaneous dosing. These results show that concurrent administration of oral deuterated and i.v. ALF, either sequentially or simultaneously, is an efficient and effective approach to assessing hepatic and intestinal CYP3A activity.
Clinical Pharmacology & Therapeutics (2011) 89 4, 562–570. doi:10.1038/clpt.2010.313
Formability of automotive friction stir welded TWB (tailor-welded blank) sheets was experimentally and numerically investigated in this work for four automotive sheets, aluminum alloy 6111-T4, ...5083-H18, 5083-O and DP590 steel sheets, each having one or two different thicknesses. In particular, formability in three applications including the simple tension test with various weld line directions, hemisphere dome stretching and cylindrical cup drawing tests was evaluated. For numerical simulations, mechanical properties previously characterized in a joint paper (
Chung et al., 2010) were utilized. To represent the mechanical properties, the non-quadratic orthogonal anisotropic yield function, Yld2000-2d, was utilized along with the (full) isotropic hardening law, while the anisotropy of the weld zone was ignored for simplicity.
Abstract Objective The best antithymocyte globulin (ATG) preparation for induction suppression in kidney transplant recipients is still not clear. The aim of this study was to identify short- and ...long-term outcomes in kidney transplant recipients who received Thymoglobulin or ATGAM as an induction agent. Methods We retrospectively reviewed patients who underwent kidney transplantation from 1996 to 2010. Recipients were classified according to the ATG preparation. Results One hundred fifty-two patients (64.4%) received thymoglobulin and 84 (35.6%) received ATGAM. The occurrence of delayed graft function in patients receiving Thymoglobulin was higher than in patients receiving ATGAM ( P = .005), but serum creatinine levels and acute rejection after kidney transplantation were not different between the two groups. The death-censored graft survival curve in Thymoglobulin recipients was higher than in ATGAM recipients ( P = .027). Bacterial infection was a predisposing factor for graft survival ( P = .008). Conclusion The efficacy of Thymoglobulin induction is generally better than that of ATGAM induction, and prevention of bacterial infections was just as important as the use of ATG because bacterial infection was an important risk factor for graft failure.
The combined effect of pH and calcium on the interactions of nonozonated and ozonated natural organic matter (NOM) with nanoscale TiO2 was investigated. The approach included characterization of TiO2 ...nanoparticles and NOM, extended Derjaguin−Landau−Verwey−Overbeek (XDLVO) modeling of NOM-TiO2 and NOM−NOM interactions, batch study on the NOM adsorption onto TiO2 surface, and bench-scale study on the treatment of NOM-containing feed waters using a hybrid process that combines ozonation and ultrafiltration with a 5 kDa ceramic (TiO2 surface) membrane. It was demonstrated that depending on pH and TiO2 loading, the adsorption of NOM species is controlled by either the availability of divalent cations or by preozonation of NOM. XDLVO surface energy analysis predicts NOM adsorption onto TiO2 in the ozone-controlled regime but not in the calcium-controlled regime. In both regimes, short-range NOM−NOM and NOM−TiO2 interactions were governed by acid−base and van der Waals forces, whereas the role of electrostatic forces was relatively insignificant. Ozonation increased the surface energy of NOM, contributing to the hydrophilic repulsion component of the NOM−NOM and NOM−TiO2 interactions. In the calcium-controlled regime, neither NOM−TiO2 nor NOM−NOM interaction controlled adsorption. Non-XDLVO interactions such as intermolecular bridging by calcium were hypothesized to be responsible for the observed adsorption behavior. Adsorption data proved to be highly predictive of the permeate flux performance.
Summary
Fusobacterium nucleatum plays a pivotal role in dental plaque biofilm formation and is known to be involved in chronic inflammatory systemic disease. However, limited knowledge of ...F. nucleatum genes expressed in vivo interferes with our understanding of pathogenesis. In this study, we identified F. nucleatum genes induced in vivo using in‐vivo‐induced antigen technology (IVIAT). Among 30,000 recombinant clones screened, 87 reacted reproducibly with pooled sera from 10 patients with periodontitis. The clones encoded for 32 different proteins, of which 28 could be assigned to their functions, which were categorized in translation, transcription, transport, energy metabolism, cell envelope, cellular process, fatty acid and phospholipid metabolism, transposition, cofactor biosynthesis, amino acid biosynthesis, and DNA replication. Putative virulence factors detected were ABC transporter, butyrate‐acetoacetate CoA‐transferase, hemin receptor, hemolysin, hemolysin‐related protein, LysR family transcriptional regulator, serine protease, and transposase. Analysis of immune responses to the in‐vivo‐induced (ivi) antigens in five patients demonstrated that most were reactive to these proteins, confirming results with pooled sera. IVIAT‐identified F. nucleatum genes in this study may accelerate the elucidation of F. nucleatum‐mediated molecular pathogenesis.
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