Germline transmission of an embryonic stem cell line derived from BALB/c cataract mice

Mice embryonic stem (ES) cells have enabled the generation of mouse strains with defined mutation(s) in their genome for putative disease loci analysis. In the study of cataract, the complex genetic background of this disease and lack of long-term self-renewal ES cells have hampered the functional researches of cataract-related genes. In this study, we aimed to establish ES cells from inherited cataract mice (BALB/CCat/Cat). Embryos of cataract mice were cultured in chemical-defined N2B27 medium with the presence of two small molecules PD0325901 and CHIR99021 (2i) and an ES cell line (named EH-BES) was successfully established. EH-BES showed long-term self-renewal in 2i medium and maintained capacity of germline transmission. Most importantly, the produced chimera and offspring developed congenital cataract as well. Flow cytometry assay revealed that EH-BES are homogeneous in expression of Oct4 and Rex1in 2i medium, which may account for their self-renewal ability. With long-term self-renewal ability and germline-competent, EH-BES cell line can facilitate genetic and functional researches of cataract-related genes and better address mechanisms of cataract.

Infusion of human umbilical cord‑derived mesenchymal stem cells effectively relieves liver cirrhosis in DEN‑induced rats

Cirrhosis is the long‑term outcome of chronic hepatic injury and no effective therapy is currently available for this disease. Mesenchymal stromal cells (MSCs) are multipotent cells that are easily acquired and amplified, and may be potential candidates for cell therapy against cirrhosis. This study aimed to determine the therapeutic effects of human umbilical cord‑derived MSCs (hUCMSCs) for the treatment of liver cirrhosis and identify an effective method for engrafting MSCs. The model of liver cirrhosis was established by induction of diethylnitrosamine (DEN) in rats. The isolated hUCMSCs were identified by morphology, flow cytometry and multilineage differentiation; they were injected into the vein of DEN‑induced rats at varied cell doses and infusion times. Biochemical analyses of the serum and histopathological analysis of the liver tissues were performed to evaluate the therapeutic effects of hUCMSCs in all treatment groups. The results indicated that isolated hUCMSCs were capable of self‑replication and differentiated into multiple lineages, including osteoblast‑, adipocyte‑ and hepatocyte‑like cells. Compared with the control group, administration of hUCMSCs at different cell doses and infusion times relieved DEN‑induced cirrhosis to varying degrees. The therapeutic effects of hUCMSCs on liver cirrhosis gradually improved with increased cell dose and infusion times. The improvement of cirrhosis was due to the capacity of hUCMSCs to breakdown collagen fibers in the liver. It was demonstrated that infusion of hUCMSCs effectively relieved liver cirrhosis by facilitating the breakdown of collagen fibers in a dose‑dependent manner and multiple infusions caused a relatively greater improvement in cirrhosis compared with a single infusion of hUCMSCs.

Germ-line-competent embryonic stem cells of the Chinese Kunming mouse strain with long-term self-renewal ability

Kunming (KM) mice are the most widely used strain in China. However, authentic embryonic stem cells (ESCs) from KM mice have never been available, and this hampers the genetic manipulation of this valuable mice strain. In this study, we show that KM ESCs can be efficiently derived and maintained in chemically defined N2B27 medium with the presence of two small molecules PD0325901 and CHIR99021 (2i medium). These KM ESCs exhibit all features of ESCs, including long-term self-renewal ability, expression of key molecular markers (Oct4, Nanog, and Sox2), the ability to form teratomas, and the capacity to incorporate into the developing embryo and then transmit through the germ line.

Characterization of two novel cell lines with distinct heterogeneity derived from a single human bile duct carcinoma

Background

Intratumoral heterogeneity reflects subclonal diversity and accounts for a variety of clinically defined phenotypes including the development of drug resistance and recurrence. However, intratumoral heterogeneity of bile duct carcinoma (BDC) is rarely studied.

Methods

Two highly heterogeneous cell lines named EH-CA1a and EH-CA1b were established from a primary tumor tissue of a pathologically proven BDC. Distinct heterogeneity and underlying mechanisms of two cell lines in karyotype, colony formation, tumorgenicity, and sensitivity to chemoradiotherapy were intensively studied.

Results

Both cell lines showed typical morphology of cancer cells. EH-CA1a cells grew as free-floating aggregates, while EH-CA1b cells grew adherently as a monolayer. EH-CA1a cells had higher cloning efficiencies and were able to keep proliferating under hypoxic condition. Coincidentally, hypoxia-induced factor-1α (HIF1α) and vascular endothelial growth factor (VEGF) mRNA were significantly higher in EH-CA1a cells than in EH-CA1b cells. Both cell lines were tumorigenic in nude mouse, however, EH-CA1a cells showed more aggressive characteristics. Most importantly, the EH-CA1a cells showed much more resistance against radiation and chemotherapy with gemcitabine. Metastasis-related genes including matrix metalloproteinase 2 (MMP-2), MMP-9, epithelial-mesenchymal transition (EMT) markers such as Vimentin, Snail, and Twist, are more highly expressed in EH-CA1a cells than in EH-CA1b cells. Moreover, the percentage of cells expressing cancer stem cell-like marker, CD133, in EH-CA1a cells is much higher than that in EH-CA1b cells. Moreover, knockdown of CD133 in both EH-CA1a and EH-CA1b cells significantly reduced their invasive potential and increased their sensitivities to radiation and gemcitabine, suggesting the differential expression of CD133 protein may partially account for the difference in malignancy between these two cancer cells.

Conclusion

Establishment of these two cell lines will not only shed light on intratumoral heterogeneities of BDC, but also potentially facilitate the development of novel therapeutic approaches of BDC.

Conversion of rat embryonic stem cells into neural precursors in chemical-defined medium

Rat embryonic stem (ES) cells hold great interest for the research of neurodevelopment and neurodegenerative diseases. However, neural conversion of rat ES cells in vitro has proven to be a challenge owing to the proliferation arrest and apoptosis. Here we report that rat ES cells can commit efficiently to a neural fate in the presence of CHIR99021 and Y-27632 (CY medium). In addition, CHIR99021 is crucial for maintaining the metabolic activity of differentiated rat ES cells, while Y-27632 facilitates the neural differentiation of rat ES cells by inhibiting bone morphogenetic protein expression. The chemical-defined CY medium also provides a platform for exploring the mechanism of neural commitment and optimizing the production efficiency of neural precursor from rat ES cells.

The combination of an oxygen-dependent degradation domain-regulated adenovirus expressing the chemokine RANTES/CCL5 and NK-92 cells exerts enhanced antitumor activity in hepatocellular carcinoma

Oncolytic adenoviruses are modified based on adenovirus serotype 5 (Ad5), which belongs to subgroup C and depends on Coxsackie-adenovirus receptor (CAR) to recognize target cells. However, expression of CAR is generally low or lost in certain tumors including hepatocellular carcinoma (HCC). By contrast, CD46 is highly expressed in various types of malignant tumor cells. Therefore, we constructed an adenovirus vector expressing the human RANTES/CCL5 gene regulated by oxygen-dependent degradation domain (ODD) and analyzed its antitumor effects in vitro and in vivo. The human RANTES/CCL5 gene was fused with ODD by PCR and the recombinant oncolytic adenovirus containing RANTES-ODD, SG511-CCL5-ODD, was constructed by the Gateway system, which infected cells by binding CD46. Viral replication experiments were performed to evaluate the selective replication ability of SG511-CCL5-ODD. RANTES expression was determined by ELISA. The chemotactic test was used to analyze the ability of the expressed RANTES to recruit NK92 cells. The antitumor effects of SG511-CCL5-ODD were examined in HCC xenografts in nude mice. A chimeric oncolytic adenovirus, SG511-CCL5-ODD, was constructed successfully. Cells infected with the recombinant virus were able to express RANTES selectively in different environments controlled by ODD and the expressed RANTES was able to recruit NK92 cells by its chemotactic effect in vitro and improve the anticancer immune response in HCC xenografts in nude mice. The chimeric adenovirus SG511-CCL5-ODD highly expressed the RANTES-ODD fusion gene in the hypoxia of HCC under the control of the ODD and effectively attracted NK92 cells and a high number of immunocytes. These factors had complementary advantages and, in combination, exerted enhanced antitumor efficacy.

Wnt/beta-catenin signaling in embryonic stem cell converted tumor cells

BACKGROUND

Embryonic stem cells (ESCs) are pluripotent stem cells and can form tumors containing cells from all three germ layers. Similarities between pluripotent stem cells and malignant tumor cells have been identified. The purpose of this study was to obtain ESCs-converted tumor cell lines and to investigate the mechanism of malignancy in pluripotent stem cells.

METHODS

Mouse ESCs were subcutaneously injected into nude mice to obtain tumors from which a tumor-like cell line (ECCs1) was established by culturing the cells in chemical-defined N2B27 medium supplied with two small molecular inhibitors CHIR99021 and PD0325901 (2i). The ECCs1 were then subcutaneously injected into nude mice again to obtain tumors from which another tumor-like cells line (ECCs2) was established in the same 2i medium. The malignant degree of ESCs, ECCs1 and ECCs2 was compared and the underlying mechanism involved in the malignancy development of ESCs was examined.

RESULTS

The three ESCs, ECCs1 and ECCs2 cell lines were cultured in the same 2i condition and showed some likeness such as Oct4-expression and long-term expansion ability. However, the morphology and the tumor-formation ability of the cell lines were different. We identified that ECCs1 and ECCs2 gradually acquired malignancy. Moreover, Wnt signaling-related genes such as CD133 and β-catenin expression were up-regulated and Frizzled related protein (FRP) was down-regulated during the tumor development of ESCs.

CONCLUSIONS

The two tumor-like cell lines ECCs1 and ECCs2 stand for early malignant development stage of ESCs and the ECCs2 was more malignant than the ECCs1. Moreover, we identified that Wnt/β-catenin signaling played an important role in the malignancy process of ESCs.

Glucose metabolism among residents in Shanghai: natural outcome of a 5-year follow-up study

BACKGROUND

Previous studies have shown that Type 2 diabetes mellitus (T2DM) is usually preceded by a condition known as pre-diabetes. However, few studies evaluate the rate of each status of impaired glucose regulation progressed to T2DM and its related metabolic disorders impacting the development.

AIM

To investigate the natural outcome of glucose metabolism among Shanghai adult residents during a 5-yr period, and estimate the metabolic characteristics related with the conversion of glucose tolerance.

SUBJECTS AND METHODS

A cross-sectional survey with multiple- stage and random sampling was conducted among 1869 adult residents from Shanghai Pudong New District in 2002. In 2007, 1042 non-diabetic subjects were successfully followed up. All the participants completed a questionnaire and underwent anthropometric measurements and a 75-g oral glucose tolerance test.

RESULTS

The incidence of diabetes was higher in isolated impaired glucose tolerance (i- IGT), isolated impaired fasting glucose (i-IFG), and combined fasting and post-prandial hyperglycemia (IFG/IGT) group when compared to that in normal glucose tolerance group, as relative ratios with 95% confidence intervals of 9.2 (5.5- 15.2), 7.5 (3.6-15.7), and 13.2 (5.8-30.2), respectively. Subjects who had 2 or more metabolic disorders had a 2-3-fold higher incidence than those with less than 1 metabolic disorder (all p<0.001).

CONCLUSIONS

People with pre-diabetes are at increased risk of diabetes, suggesting the need for frequent screening in theloe people with several metabolic disorders.

A high resolution and large solid angle x-ray Raman spectroscopy end-station at the Stanford Synchrotron Radiation Lightsource

We present a new x-ray Raman spectroscopy end-station recently developed, installed, and operated at the Stanford Synchrotron Radiation Lightsource. The end-station is located at wiggler beamline 6-2 equipped with two monochromators-Si(111) and Si(311) as well as collimating and focusing optics. It consists of two multi-crystal Johann type spectrometers arranged on intersecting Rowland circles of 1 m diameter. The first one, positioned at the forward scattering angles (low-q), consists of 40 spherically bent and diced Si(110) crystals with 100 mm diameters providing about 1.9% of 4π sr solid angle of detection. When operated in the (440) order in combination with the Si (311) monochromator, an overall energy resolution of 270 meV is obtained at 6462.20 eV. The second spectrometer, consisting of 14 spherically bent Si(110) crystal analyzers (not diced), is positioned at the backward scattering angles (high-q) enabling the study of non-dipole transitions. The solid angle of this spectrometer is about 0.9% of 4π sr, with a combined energy resolution of 600 meV using the Si (311) monochromator. These features exceed the specifications of currently existing relevant instrumentation, opening new opportunities for the routine application of this photon-in/photon-out hard x-ray technique to emerging research in multidisciplinary scientific fields, such as energy-related sciences, material sciences, physical chemistry, etc.

A transanal procedure using an endoscopic linear stapler for obstructed defecation syndrome: the first Chinese experience

BACKGROUND

Transanal surgery using an endoscopic linear stapler is a recognized, but not widely performed technique for the treatment of obstructed defecation syndrome (ODS). A study of consecutive patients was conducted to evaluate the safety and effectiveness of the technique for the treatment of ODS in Chinese patients.

METHODS

From November 2008 to December 2010, 43 female patients with ODS caused by rectocele and/or rectal intussusception underwent transanal surgery using an endoscopic linear stapler in three Chinese hospitals. Clinical and functional data including the Wexner constipation score and outcome classification were analyzed retrospectively.

RESULTS

The average duration of surgery was 23 ± 4 min (range 15-30 min). Blood loss was 10 ± 2 ml (range 5-15 ml). The average postoperative hospital stay was 5 days (range 4-6 days). The pathologic findings showed that the specimen contained rectal muscle in all patients. Postoperative complications included 4 patients with transient fecal urgency, 3 patients with anorectal pain, and one patient with mild bleeding from the stapled suture line. Three patients reported minor fecal incontinence (Wexner score less than 3). During a median follow-up of 12 months (range, 3-26 months), the mean constipation score improved from preoperative 13.56 to postoperative 5.07 at 1 year (P < 0.05). The outcome at 1 year was excellent in 18 of 43 patients, good in 13, fairly good in 7, and poor in 5. Postoperative defecography was performed in 28 patients. Rectocele disappeared in 15 patients. Rectocele depth was reduced from 34 ± 4 mm preoperatively to 17 ± 3 mm postoperatively (P < 0.05).

CONCLUSION

The transanal procedure using an endoscopic linear stapler is an easy, safe, and effective option for selected patients with ODS. Long-term prospective, randomized, controlled studies are needed to confirm the advantages of this procedure in comparison with the traditional transanal and stapled transanal rectal resection (STARR) techniques.

hSulf-1 gene exhibits anticancer efficacy through negatively regulating VEGFR-2 signaling in human cancers

Background

Human sulfatase 1 (hSulf-1) is a heparin-degrading endosulfatase that desulfates cell surface heparan sulfate proteoglycans (HSPGs) in extracellular matrix and negatively modulates heparin-binding growth factor and cytokine signaling in cell proliferation. But hSulf-1 function is more complicated, and its molecular mechanism has not been well known.

Principal Findings

To further investigate the functions of hSulf-1 gene in regulating the vascular endothelial growth factor receptor (VEGFR) signaling, a series of vectors expressing hSulf-1, hSulf-1 small hairpin RNA (shRNA) and VEGFR-2 shRNA were generated. hSulf-1 re-expression could downregualte the VEGFR-2 phosphorylation and inhibit cancer cell proliferation both in ovarian and hepatocellular cancer cell lines. Knockdown of hSulf-1 expression by hSulf-1 shRNA enhanced the recovery of high levels of phosphorylated VEGFR-2, and knockdown of VEGFR-2 expression by VEGFR-2 shRNA inhibited the proliferation activity of cancer cells in vitro to some extent. In human cancer xenografts in nude mice, tumor growth was inhibited markedly after injections of adenovirus expressing hSulf-1, with the tumor inhibition rates of 46.19% and 49.56% in ovarian and hepatocellular tumor models, respectively. hSulf-1 expression significantly reduced tumor microvessel density.

Conclusions

The results demonstrated that hSulf-1 re-expression both in ovarian and hepatocellular cancer cells induces antitumor efficacy by attenuating the phosphorylation of VEGFR-2 and suppressing angiogenesis. Therefore, hSulf-1-mediated antiproliferation and antiangiogenesis could be a reasonable approach for cancer therapy.

Use of microRNA Let-7 to control the replication specificity of oncolytic adenovirus in hepatocellular carcinoma cells

Highly selective therapy for hepatocellular carcinoma (HCC) remains an unmet medical need. In present study, we found that the tumor suppressor microRNA, let-7 was significantly downregulated in a proportion of primary HCC tissues (12 of 33, 36.4%) and HCC cell lines. In line with this finding, we have engineered a chimeric Ad5/11 fiber oncolytic adenovirus, SG7011^let7T, by introducing eight copies of let-7 target sites (let7T) into the 3′ untranslated region of E1A, a key gene associated with adenoviral replication. The results showed that the E1A expression (both RNA and protein levels) of the SG7011^let7T was tightly regulated according to the endogenous expression level of the let-7. As contrasted with the wild-type adenovirus and the control virus, the replication of SG7011^let7T was distinctly inhibited in normal liver cells lines (i.e. L-02 and WRL-68) expressing high level of let-7 (>300 folds), whereas was almost not impaired in HCC cells (i.e. Hep3B and PLC/PRF/5) with low level of let-7. Consequently, the cytotoxicity of SG7011^let7T to normal liver cells was successfully decreased while was almost not attenuated in HCC cells in vitro. The antitumor ability of SG7011^let7Tin vivo was maintained in mice with Hep3B xenograft tumor, whereas was greatly decreased against the SMMC-7721 xenograft tumor expressing a high level of let-7 similar with L-02 when compared to the wild-type adenovirus. These results suggested that SG7011^let7T may be a promising anticancer agent or vector to mediate the expression of therapeutic gene, broadly applicable in the treatment for HCC and other cancers where the let-7 gene is downregulated.

P16 reactivation induces anoikis and exhibits antitumour potency by downregulating Akt/survivin signalling in hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is one of the most malignant tumours with high rate of recurrence and metastasis. In HCC, deficiency of the P16/CDK4/Rb pathway is a frequent molecular event, and transferring the P16 gene into cancer cells can induce cell cycle arrest and apoptosis, suggesting that the P16 gene is a good target in cancer gene therapy. The previous study demonstrated that P16 re-expression mediated by adenovirus within cancer cells can induce cell apoptosis and exert potent antitumour efficacy in cancer xenografts in nude mice. However, the molecular mechanism of P16-induced apoptosis in cancer cells is not clear yet. In this resulting study, we found that P16 re-expression can downregulate survivin expression in HCC cells. As a member of the inhibitors of the apoptotic gene family, survivin has been reported to be overexpressed in most common human cancers and present multiple physiological and pathological functions including cell cycle control, inhibition of cell apoptosis, regulation of cell division and induction of angiogenesis, etc. Further investigation found that P16 reactivation led to a decrease of phosphorylated Akt on Thr308 and phosphorylated survivin on Thr34, then downregulated survivin expression. The P16-mediated decrease of nuclear survivin in cancer cells limited CDK4 import into nuclei, which restrained CDK4 functions of promoting cell proliferation, then exhibited the effect of cell cycle arrest and induction of detachment-induced apoptosis (anoikis). The antitumor potency of P16 by downregulating the Akt/survivin signalling was also demonstrated in HCC xenograft models in nude mice. This new insight into P16 function would help in designing better strategies for cancer gene therapy.

Enhanced antitumor efficacy of a novel fiber chimeric oncolytic adenovirus expressing p53 on hepatocellular carcinoma

Oncolytic adenoviruses may offer a new treatment option and improve the prognosis for patients with hepatocellular carcinoma (HCC). However, the antitumor efficacy of oncolytic adenoviruses on HCC cells is compromised due to low expression of the adenovirus serotype 5 (Ad5) receptor on the target cells. In this study we showed that all HCC cell lines and clinical samples expressed high level of CD46, the receptor for Adenovirus 35 (Ad35) and constructed new fiber chimeric oncolytic adenoviruses with or without a p53 gene expression cassette, SG635-p53 and SG635, respectively. These variants were derived from the previously described Ad5 vectors SG600-p53 and SG600 by replacing the Ad5 fiber with a chimeric Ad5/35 fiber. It was found that the 5/35 fiber chimeric adenovirus vector (Ad5/35-EGFP) demonstrated significantly improved transduction in all tested HCC cell lines compared with the Ad5 vector (Ad5-EGFP). The new fiber chimeric oncolytic adenoviruses produced more progeny viruses in HCC cells than did the Ad5-based viruses but replicated weakly in normal fibroblast BJ cells. In addition, SG635-p53 mediated a higher level of transgenic expression than SG600-p53 in Hep3B and Huh7 cells and showed a markedly enhanced antitumor effect on HCC cells in vitro compared with SG635 or SG600-p53 without causing significant cytotoxicity to normal cells. Antitumor activity of SG635-p53 was shown in Hep3B subcutaneous xenograft tumor models following intratumoral injection, resulting in significant inhibition of tumor growth and prolonged survival of animals. Our data suggest that SG635-p53, as a fiber chimeric oncolytic adenovirus in combination with p53 expression, may serve as a novel, promising and safe anticancer agent for the treatment of HCC.

De novo AL amyloidosis in the kidney allograft

We report four cases of de novo amyloidosis occurring after 16, 18, 28 and 31 years following kidney transplantation. These patients presented with proteinuria and progressive allograft dysfunction. Kidney biopsy showed AL amyloidosis in all compartments of the allograft kidney. Serum immunofixation studies revealed monoclonal lambda light chains in all four cases. Bone marrow examination showed 10% plasma cells in one case, 5-10% in two cases and less than 5% in one case. Two patients died unexpectedly within 3 months and 1 year of the diagnosis of allograft AL amyloidosis. Of the remaining two, one underwent autologous stem cell transplant that resulted in complete hematologic remission. However, the patient relapsed within 2 years and also developed progressive kidney allograft failure. The patient received a second autologous stem cell transplant with complete hematologic response, followed by a second kidney transplant, which showed no evidence of amyloid at 1-year posttransplant. The remaining case was treated with prednisone and bortezomib, which has stabilized kidney function in the short term. In conclusion, this study shows that AL amyloidosis is an uncommon but important cause of late onset proteinuria in the kidney allograft that results in kidney allograft failure.

A novel conditionally replicating "armed" adenovirus selectively targeting gastrointestinal tumors with aberrant wnt signaling

Using conditionally replicating adenoviral vectors (CRAds) is a promising strategy in the treatment of solid tumors. The prospective of this study was to design a novel CRAd for the treatment of gastrointestinal cancer and show its efficacy in vitro, as well as in vivo. To determine if aberrant wnt signaling in tumor cells can be used to selectively drive viral replication, we analyzed six colorectal and hepatocellular cell lines, as well as 13 colorectal tumors and 17 gastric tumors, for β-catenin mutation status or aberrant wnt signaling, both of which were found frequently. Based on these findings, a novel CRAd (Ad5F11.wnt-E1A-hIL24) containing an E1A expression cassette driven by an artificial wnt promoter and delivering an apoptosis-inducing gene, interleukin-24 (IL24), was engineered. To enhance infection efficiency, the virus was pseudotyped by replacing adenovirus serotype 5 (Ad5) with Ad11 fiber. Ad5F11.wnt-E1A-hIL24 virus exhibited high selectivity toward cells with aberrant wnt signaling both in vitro and in mouse xenograft tumors. Transduction efficiency was significantly improved compared with that of nonpseudotyped control viruses. The proliferation of tumor cell lines, as well as tumor growth, in mouse xenografts could be profoundly inhibited by viral infection with Ad5F11.wnt-E1A-hIL24. The therapeutic effect was associated with increased apoptosis through caspase-3 activation. In addition, Ad5F11b vector exhibited a more favorable biodistribution, blood clearance, and transgene expression compared with conventional Ad5 vector after systemic or intratumoral injection in human gastrointestinal cancer xenografts. We think that our approach is a promising strategy in the treatment of gastrointestinal cancer, warranting further clinical investigation.

5/35 fiber-modified conditionally replicative adenovirus armed with p53 shows increased tumor-suppressing capacity to breast cancer cells

Conditionally replicative adenoviruses (CRAds) are widely used for cancer biotherapy and show a significant growth-suppressing effect on many types of cancer. However, it was reported that breast cancer was highly resistant to the infection of traditionally used adenovirus of serotype 5 (Ad5)-based CRAds. Although partial substitution of the fiber protein of replication-deficient Ad5 with that of adenovirus of serotype 35 (Ad35) facilitated infection of breast cancer cells by adenoviral vectors, it is still unknown whether this modification can improve CRAds in their tumor-eliminating capacity. We generated a 5/35 fiber-modified CRAd with a p53 cDNA construct and investigated whether this alteration in fiber region can make CRAds suppress the growth of breast cancer more effectively. Our data reinforced the proposal that 5/35-modified fiber conferred higher adenovirus infectivity for breast cancer cells than natural Ad5 fiber. Interestingly, 5/35 fiber-modified CRAd replicated more efficiently in breast cancer cells than Ad5-based CRAd. We also found 5/35 fiber-modified CRAd mediated higher expression of p53 in breast cancer cells. In vitro, 5/35 fiber-modified CRAd eliminated breast cancer cells more efficiently. Growth of xenograft tumors in nude mice was also significantly retarded by 5/35 fiber-modified CRAd. The 5/35 fiber-modified CRAd suppressed the growth of breast cancer cells more effectively than Ad5-based CRAd, both in vitro and in vivo. Thus CRAd with 5/35 hybrid fiber may be a promising vector for breast cancer treatment.

Enhanced 2.0 microm emission and gain coefficient of transparent glass ceramic containing BaF2: Ho3+,Tm3+ nanocrystals

Transparent glass ceramic containing BaF(2):Ho(3+),Tm(3+) nanocrystals has been prepared by melt quenching and subsequent thermal treatment. The precipitation of BaF(2) nanocrystals was confirmed by X-ray diffraction and high-resolution transmission electron microscopy. Intense 2.0 microm fluorescence originating from Ho(3+): (5)I(7) --> (5)I(8) transition was achieved upon excitation with 808 nm laser diode. A large ratio of forward Tm(3+) --> Ho(3+) energy transfer constant to that of backward process indicated high efficient energy transfer from Tm(3+)((3)F(4)) to Ho(3+)((5)I(7)), benefited from the reduced ionic distances of Tm(3+)-Tm(3+) and Tm(3+)-Ho(3+) pairs and low phonon energy environment with the incorporation of rare-earth ions into the precipitated BaF(2) nanocrystals. The results indicate that glass ceramic is a promising candidate material for 2.0 microm laser.

Humanized anti-EphB4 antibodies for the treatment of carcinomas and vasculogenesis-related diseases

The invention provides human, humanized or chimeric versions of anti-EphB4 mouse monoclonal antibodies that bind to the human EphB4 receptor tyrosine kinase. The described anti-EphB4 antibodies are derived from two murine mAbs #47 and #131 through framework shuffling and include those of the IgGl, IgG2, IgG3 or IgG4 human isotype. The patent further relates to pharmaceutical compositions, immunotherapeutic compositions and methods using therapeutic antibodies that bind to the human EphB4 antigen and that may induce phosphorylation and degradation of EphB4 and mediate antigen-dependent cell-mediated-cytotoxicity, complement-dependent cell-mediated cytotoxicity and/or apoptosis for the treatment of human malignancies and vasculogenesis-related disorders and diseases.

E1B 55-kDa deleted, Ad5/F35 fiber chimeric adenovirus, a potential oncolytic agent for B-lymphocytic malignancies

BACKGROUND

Conditionally replicative adenovirus (CRAd) provides a promising strategy for solid tumor therapy. However, relatively few studies have been addressed on hematopoietic malignancies. We previously found that ZD55, a serotype 5 (Ad5)-based, E1B 55-kDa deleted CRAd, inhibited leukemic cell growth and induced apoptosis. In the present study, we employed SG235, a new CRAd with both an E1B 55-kDa deletion and an Ad5/F35 chimeric fiber, for the treatment of B-cell tumors.

METHODS

CRAd SG235 was engineered not to express adenovirus E1B 55-kDa gene, and the wild-type Ad5 fiber was replaced by a chimeric Ad5/35 fiber containing an Ad5 tail, an Ad35 shaft and an Ad35 knob. Using in vitro and in vivo experiments, the infectivity and selective cytotoxicity of SG235 on B-cell tumor lines were evaluated. Apoptosis-related signaling elements were investigated.

RESULTS

SG235 significantly suppressed malignant B-cell growth in vitro and in vivo. In addition to selective cytolysis, SG235-induced apoptosis in the tumor cells. Upon SG235 infection, levels of cleaved forms of caspase-3 and poly(adenosine diphosphate-ribose) polymerase increased, suggesting that SG235 induces apoptosis in malignant B-cells by activating a caspase cascade. Furthermore, SG235 infection resulted in an up-regulated level of Bax, as well as down-regulated levels of xIAP, cIAP and survivin, suggesting that infection of SG235 induces apoptosis in B-cell tumor lines by affecting both apoptosis-promoting and -inhibiting intracellular signaling elements.

CONCLUSIONS

CRAd SG235 may serve as a potential anticancer agent, or a therapeutic vehicle for harboring anticancer genes, in B-cell tumor treatment.

An anti-preS2 antibody protects human hepatocytes from hepatitis B virus infection

BACKGROUND

Hepatitis B virus infection is a major problem in liver transplantation. In this study, we examined the potential efficay of a recombinant adenovirus expressing an antibody against the HBV preS2 antigen (Ab-H-HBV-S2) in preventing HBV recurrent infection after liver transplantation.

METHODS

A gene for humanized antibody against the HBV preS2 antigen was cloned into pDC315, a type 5 adenoviral shuttle plasmid. Recombinant virus was obtained by homologous recombination in the 293 packaging cells. The virus containing the Ab-H-HBV-S2 gene was transduced into the rat liver graft during cold preservation. The recombinant virus produced antibody and showed protective effects on human hepatocytes from hepatitis B virus infection in vitro.

RESULTS

The recombinant virus titer determined by TCID50 analysis was 5.1x10(10) PFU/mL. The concentration of preS2 antibody in BALB/C nude mice was 16.7 +/- 10.5 microg/mL on day 3,30.9 +/- 13.6 pg/mL on day 7, and lasted for 5 weeks after the injection. At a concentration of 0.5 microg/mL or above, the preS2 antibody protected cultured human hepatocytes from hepatitis B virus.

CONCLUSIONS

Adenovirus-mediated gene transduction of anti-preS2 antibody in the transplanted liver may be a useful approach to prevent hepatitis B infection after liver transplantation.

Effective gene-viral therapy of leukemia by a new fiber chimeric oncolytic adenovirus expressing TRAIL: in vitro and in vivo evaluation

Conditionally replicating adenoviruses (CRAd) have been under extensive investigations as anticancer agents. Previously, we found that ZD55, an adenovirus serotype 5-based CRAd, infected and killed the leukemia cells expressing coxsackie adenovirus receptor (CAR). However, majority of leukemic cells lack CAR expression on their cell surface, resulting in resistance to CRAd infection. In this study, we showed that SG235, a novel fiber chimeric CRAd that has Ad35 tropism, permitted CAR-independent cell entry, and this in turn produced selective cytopathic effects in a variety of human leukemic cells in vitro and in vivo. Moreover, SG235 expressing exogenous tumor necrosis factor-related apoptosis-inducing ligand (SG235-TRAIL) effectively induced apoptosis of leukemic cells via the activation of extrinsic and intrinsic apoptotic pathway and elicited a superior antileukemia activity compared with SG235. In addition, normal hematopoietic progenitors were resistant to the inhibitory activity of SG235 and SG235-TRAIL. Our data suggest that these novel oncolytic agents may serve as useful tools for the treatment of leukemia.

Efficacy of systematic pelvic lymphadenectomy in endometrial cancer (MRC ASTEC trial): a randomised study

BACKGROUND

Hysterectomy and bilateral salpingo-oophorectomy (BSO) is the standard surgery for stage I endometrial cancer. Systematic pelvic lymphadenectomy has been used to establish whether there is extra-uterine disease and as a therapeutic procedure; however, randomised trials need to be done to assess therapeutic efficacy. The ASTEC surgical trial investigated whether pelvic lymphadenectomy could improve survival of women with endometrial cancer.

METHODS

From 85 centres in four countries, 1408 women with histologically proven endometrial carcinoma thought preoperatively to be confined to the corpus were randomly allocated by a minimisation method to standard surgery (hysterectomy and BSO, peritoneal washings, and palpation of para-aortic nodes; n=704) or standard surgery plus lymphadenectomy (n=704). The primary outcome measure was overall survival. To control for postsurgical treatment, women with early-stage disease at intermediate or high risk of recurrence were randomised (independent of lymph-node status) into the ASTEC radiotherapy trial. Analysis was by intention to treat. This study is registered, number ISRCTN 16571884.

FINDINGS

After a median follow-up of 37 months (IQR 24-58), 191 women (88 standard surgery group, 103 lymphadenectomy group) had died, with a hazard ratio (HR) of 1.16 (95% CI 0.87-1.54; p=0.31) in favour of standard surgery and an absolute difference in 5-year overall survival of 1% (95% CI -4 to 6). 251 women died or had recurrent disease (107 standard surgery group, 144 lymphadenectomy group), with an HR of 1.35 (1.06-1.73; p=0.017) in favour of standard surgery and an absolute difference in 5-year recurrence-free survival of 6% (1-12). With adjustment for baseline characteristics and pathology details, the HR for overall survival was 1.04 (0.74-1.45; p=0.83) and for recurrence-free survival was 1.25 (0.93-1.66; p=0.14).

INTERPRETATION

Our results show no evidence of benefit in terms of overall or recurrence-free survival for pelvic lymphadenectomy in women with early endometrial cancer. Pelvic lymphadenectomy cannot be recommended as routine procedure for therapeutic purposes outside of clinical trials.

Thermal stability and spectroscopic properties of Er3+-doped antimony-borosilicate glasses

This paper reports on the optical spectroscopic properties and thermal stability of Er3+-doped antimony-borosilicate glasses for developing 1.5 microm optical amplifiers. Upon excitation at 980 nm laser diode, an intense 1.5 microm infrared fluorescence has been observed with the maximum full width at half maximum (FWHM) of 90 nm for Er3+-doped antimony-borosilicate glasses. The emission cross-section and the lifetime of the 4I13/2 level of Er3+ ions are 6.3 x 10(-21) cm2 and 0.30 ms, respectively. It is noted that the product of the emission cross-section and FWHM of the glass studied is as great as 567 x 10(-21) cm2 nm, which is comparable or higher than that of bismuthate and tellurite glasses.