Perinatal characteristics and neonatal outcomes of singletons and twins in Chinese very preterm infants: a cohort study.

BACKGROUND: The prevalence of preterm birth has been rising, and there is a paucity of nationwide data on the perinatal characteristics and neonatal outcomes of twin deliveries of very preterm infants (VPIs) in China. This study compared the perinatal characteristics and outcomes of singletons and twins admitted to neonatal intensive care units (NICUs) in China. METHODS: The study population comprised all infants born before 32 weeks in the Chinese Neonatal Network (CHNN) between January 2019 and December 2019. Three-level and population-average generalized estimating equation (GEE)/alternating logistic regression (ALR) models were used to determine the association of twins with neonatal morbidities and the use of NICU resources. RESULTS: During the study period, there were 6634 (71.2%) singletons and 2680 (28.8%) twins, with mean birth weights of 1333.70 g and 1294.63 g, respectively. Twins were significantly more likely to be delivered by caesarean section (p < 0.01), have antenatal steroid usage (p = 0.048), have been conceived by assisted reproductive technology (ART) (p < 0.01), have a higher prevalence of maternal diabetes (p < 0.01) and be inborn (p < 0.01) than singletons. In addition, twins had a lower prevalence of small for gestational age, maternal hypertension, and primigravida mothers than singletons (all p < 0.01). After adjusting for potential confounders, twins had higher mortality rates (adjusted odds ratio [AOR] 1.28, 95% confidence interval [CI] 1.10-1.49), higher incidences of short-term composite outcomes (AOR 1.28, 95% CI 1.09-1.50), respiratory distress syndrome (RDS) (AOR 1.30, 95% CI 1.12-1.50), and bronchopulmonary dysplasia (BPD) (AOR 1.10, 95% CI 1.01-1.21), more surfactant usage (AOR 1.22, 95% CI 1.05-1.41) and prolonged hospital stays (adjusted mean ratio 1.03, 95% CI 1.00-1.06), compared to singletons. CONCLUSION: Our work suggests that twins have a greater risk of mortality, a higher incidence of RDS and BPD, more surfactant usage, and longer NICU stays than singletons among VPIs in China.

Association of preterm outcome with maternal systemic lupus erythematosus: a retrospective cohort study.

BACKGROUND: Maternal systemic lupus erythematosus (SLE) is at greater risk of pregnancy complications and is associated with increased risk of preterm delivery. However hardly any study has looked at the influence of SLE on the outcomes of preterm infants. This study aimed to explore the influence of SLE on the outcomes of preterm infants. METHODS: In this retrospective cohort study, preterm infants born to mothers with SLE from Shanghai Children's Medical Center during 2012 to 2021 were enrolled. Infants were excluded if they were died during hospitalization or has major congenital anomalies and neonatal lupus. Exposure was defined as mother diagnosed SLE before or during pregnancy. Maternal SLE group was matched with Non-SLE group by gestational age, birth weight and gender. Clinical data has been extracted from patients' records and registered. Major morbidities of premature and biochemical parameters in the two groups were compared using multiple logistic regression. RESULTS: One hundred preterm infants born to 95 mothers with SLE were finally enrolled. The mean (standard deviation) of gestational age and birth weight were 33.09 (7.28) weeks and 1768.50 (423.56) g respectively. There was no significant difference in major morbidities between SLE group and non-SLE group. Compared with non-SLE group, SLE off-spring had significantly lower leukocytes, neutrophiles after birth, neutrophils and platlet in one week (mean difference: -2.825, -2.001, -0.842, -45.469, respectively). Among SLE group, lower birth weight and smaller gestational age were observed in SLE mothers with disease active during pregnancy, kidney involved, blood system involved and not taking Aspirin during pregnancy. In the multivariable logistic regression analysis, exposure to aspirin during pregnancy reduced the risk of very preterm birth and increased the incidence of survive without major morbidities among preterm infants born to SLE mothers. CONCLUSION: Born to mothers with SLE may not increase the risk of major premature morbidities, but the hematologic profile of SLE preterm infants may be different from preterm infants born to women without SLE. The outcome of SLE preterm infants is associated with maternal SLE status and may benefit from maternal aspirin administration.

A novel immunocompetent murine tumor model for the evaluation of RCAd-enhanced RDAd transduction efficacy.

Low gene transfer rate in tumors, high dose-induced acute inflammatory response, and lack of an immunocompetent preclinical animal model to accurately reflect the therapeutic efficacy are prominent reasons for the lack of clinical success of adenoviral (Ad) vectors. In this study, we tested whether human replication-competent adenovirus (RCAd) can replicate in T739 mouse bladder transitional tumor cells (BTT) and lung adenocarcinoma cells (LA795), and whether RCAd can enhance the transduction rate and transgene expression of human replication defective adenoviruses (RDAd) in these tumor cells in vitro and in vivo. We demonstrated that human RCAd exhibited good infectability and cytopathologic effects in mouse BTT and LA795 cells, which was comparable to that in A549 and NCIH460 human tumor cells. In contrast, no infectability and cytopathologic effects were observed in other three mouse tumor cells such as 4T1, B16, and Lewis cells. The combined use of RCAd with RDAd significantly enhanced RDAd transduction efficiency in BTT and LA795 tumor cells in vitro and in vivo. When BTT and LA795 cells were co-infected with RDAd Ad-EGFP and RCAd, a large amount of E1a expression and 2-3 orders of increases in Ad-EGFP genomic DNA were observed. In contrast, the expression of the late gene Hexon is very low, which may explain ineffective packaging of viral particles. In conclusion, our study provided a novel immunocompetent animal model which is useful for evaluating RCAd infectability, cytopathy, and replication. The combined use of RCAd and RDAd provided a new solution for cancer gene therapy.

A Novel Compound Heterozygous Mutation in the DNAH11 Gene Found in Neonatal Twins With Primary Ciliary Dyskinesis.

Background: Primary ciliary dyskinesia (PCD) is a rare genetically heterogeneous disorder of motile cilia. Common features of PCD include upper and lower respiratory tract disease, secretory otitis media, situs inversus and fertility problems. To date, although several PCD-associated genes have been identified, the genetic causes of most PCD cases remain elusive. Methods: In this case study, we analyzed the clinical and genetic data of one case of monochorionic diamniotic twins which were suspected of having PCD on the basis of clinical and radiological features including situs inversus, recurrent wet cough and sinusitis as well as varying degrees of respiratory distress. Whole-exome sequencing was performed to identify variants of the DNAH11 gene in the twins. Sanger sequencing and real-time quantitative polymerase chain reaction (RT-qPCR) were used for validation of DNAH11 variants both in the patient and the twins. Results: In the twins, we found a novel mutation at c.2436C > G (p.Y812 *) and a pathogenic deletion encompassing 2.0 Kb of 7P15.3 ([GRCh38] chr7: g.21,816,397-21,818,402). The deleted region included exons 64 and 65 of DNAH11. Sanger sequencing also revealed that the twins' father was a carrier of heterozygous C.2436C > G and a heterozygous deletion was detected in the mother. No other clinically relevant genetic variants were identified. Conclusion: We describe a novel DNAH11 gene compound heterozygous mutation in newborn twins with PCD and recommend that PCD diagnosis should be considered in newborns presenting with respiratory distress and/or situs inversus. Early diagnosis and treatment of PCD will help control disease progression and improve the patient's quality of life.

Cleidocranial Dysplasia Causing Respiratory Distress in Neonates: A Case Report and Literature Review.

Cleidocranial dysplasia (CCD; OMIM 119600) is a rare autosomal dominant skeletal dysplasia, which is mainly characterized by persistently open or delayed closure of fontanelle, patent skull sutures, abnormal clavicles, pectus excavatum, short stature, supernumerary teeth, and sinus and middle ear infections. It is caused by Runt-related transcription factor 2 (RUNX2; OMIM 600211) mutations. Herein, we present a rare case of CCD with neonatal respiratory distress, who had abnormal midfacial features and wide fontanelle. Also, pectus excavatum was noted. He was transferred to our department, administered standard medical treatment, and discharged after 4 weeks. Therefore, we recommend the early suspicion and identification of this rare inherited disease to adequate treatment.

The effects of a biodegradable Mg-based alloy on the function of VSMCs via immunoregulation of macrophages through Mg-induced responses.

BACKGROUND: Restenosis is one of the worst side effects of percutaneous coronary intervention (PCI) due to neointima formation resulting from the excessive proliferation and migration of vascular smooth muscle cells (VSMCs) and continuous inflammation. Biodegradable Mg-based alloy is a promising candidate material because of its good mechanical properties and biocompatibility, and biodegradation of cardiovascular stents. Although studies have shown reduced neointima formation after Mg-based CVS implantation in vivo, these findings were inconsistent with in vitro studies, demonstrating magnesium-mediated promotion of the proliferation and migration of VSMCs. Given the vital role of activated macrophage-driven inflammation in neointima formation, along with the well-demonstrated crosstalk between macrophages and VSMCs, we investigated the interactions of a biodegradable Mg-Nd-Zn-Zr alloy (denoted JDBM), which is especially important for cardiovascular stents, with VSMCs via macrophages. METHODS: JDBM extracts and MgCl2 solutions were prepared to study their effect on macrophages. To study the effects of the JDBM extracts and MgCl2 solutions on the function of VSMCs via immunoregulation of macrophages, conditioned media (CM) obtained from macrophages was used to establish a VSMC-macrophage indirect coculture system. RESULTS: Our results showed that both JDBM extracts and MgCl2 solutions significantly attenuated the inflammatory response stimulated by lipopolysaccharide (LPS)-activated macrophages and converted macrophages into M2-type cells. In addition, JDBM extracts and MgCl2 solutions significantly decreased the expression of genes related to VSMC phenotypic switching, migration, and proliferation in macrophages. Furthermore, the proliferation, migration, and proinflammatory phenotypic switching of VSMCs were significantly inhibited when the cells were incubated with CMs from macrophages treated with LPS + extracts or LPS + MgCl2 solutions. CONCLUSIONS: Taken together, our results suggested that the magnesium in the JDBM extract could affect the functions of VSMCs through macrophage-mediated immunoregulation, inhibiting smooth muscle hyperproliferation to suppress restenosis after implantation of a biodegradable Mg-based stent.

Role of SOCS3 in enhanced acute-phase protein genes by neonatal macrophages in response to IL-6.

BACKGROUND: Interleukin 6 (IL-6) induce the inflammatory response directly related with the morbidity and mortality of neonatal. Here we aimed to explore the mechanism of IL-6 in neonatal inflammatory response by studying the IL-6/STAT3 signaling pathway. METHODS: Cord blood samples from health term neonatal and peripheral venous blood from health volunteers were collected. The monocytes of adults and cord blood were isolated and induced into macrophages. Then the macrophages were pretreated with or without MG132 before IL-6 stimulation. Proteins were analyzed by Western blot, mRNA by real time PCR and membrane molecule by flow cytometry. RESULTS: The acute phase protein gene expression in neonatal macrophages after stimulated with IL-6 were higher than that in adult. Significantly enhanced phosphorylation of STAT3 was seen in neonatal macrophages. Both mRNA and protein expression of SOCS3 in neonatal macrophages were lower than that in adult. After pretreated with MG132, the expression of SOCS3 protein was increased which lead to attenuate the STAT3 phosphorylation and APP gene expression. CONCLUSION: Neonatal exhibit an enhanced expression of downstream target genes and IL-6/STAT3 signal pathway which is related with the diminished SOCS3. This provides a new sight into inflammatory responses in neonatal.

Data Quality Improvement and Internal Data Audit of the Chinese Neonatal Network Data Collection System.

Background: The Chinese Neonatal Network (CHNN) is a nationwide neonatal network that aims to improve clinical neonatal care quality and short- and long-term health outcomes of infants. This study aims to assess the quality of the Chinese Neonatal Network database by conducting an internal audit of data extraction. Methods: A data audit was performed by independently replicating the data collection and entry process in all 58 tertiary neonatal intensive care units (NICU) participating in the CHNN. Eighty-eight data elements selected for re-abstraction were classified into three categories (critical, important, less important), and agreement rates for original and re-abstracted data were predefined. Three to five records were randomly selected at each site for re-abstraction, including one short- (0-7 days), two medium- (8-28 days), and two long-stay (more than 28 days) cases. Agreement rates for each data item were calculated for individual NICUs and across the network, respectively. Results: A total of 283 cases and 24,904 data fields were re-abstracted. The agreement rates for original and re-abstracted data elements were 96.1% overall, and 97.2, 94.3, and 96.6% for critical, important, and less important data elements, respectively. Individual site variation for discrepancies ranged between 0.0 and 18.4% for all collected data elements. Conclusion: The completeness, precision, and quality of data in the CHNN database are high, providing assurance for multipurpose use, including health service evaluation, quality improvement, clinical trials, and other research.

Low dosage 5-fluorouracil increases the transfection efficiency of Ad/VEGF-A in mouse lung carcinoma cell line LA795 and inhibits tumor growth.

BACKGROUND AND OBJECTIVE: Adenovirus vectors were widely used in gene therapy for tumors. We used adenovirus vector to transfer small interfering RNA (siRNA) against vascular epithelium growth factor A (VEGF-A) molecules to mouse lung adenoma LA795 cells and used low dose of chemotherapeutic drugs to further elevate the infection efficiency of adenovirus vector in and therapeutic effect of RNAi on tumor cells. METHODS: LA795 cells were infected by Ad/EGFP and treated with different dosages of gemcitabin, epirubicin, cisplatin, or 5-fluorouracil (5-FU). Cells were observed under fluorescence microscope continuously using green fluorescent protein (GFP) as the reporter gene. The percentage of GFP-positive cells and fluorescent intensity were tested by flow cytometry to determine optimum concentrations of drugs. Ad/siVEGF-A containing VEGF-A siRNA was constructed. Real-time PCR and ELISA were applied to measure the expression level of VEGF-A after LA795 cells were infected by Ad/siVEGF-A and treated with 5-FU. The combination of Ad/siVEGF-A and 5-FU was also applied in treating subcutaneous tumor in mice. RESULTS: Low dose of 5-FU elevated the Ad/EGFP infection in LA795 cells significantly, and also enhanced the effect of Ad/siVEGF-A in down-regulating VEGF-A mRNA and protein levels in tumor cells. When used in tumor in vivo, the combination strategy repressed tumor growth effectively. CONCLUSION: Low dose of 5-FU can enhance the capability of adenovirus infecting tumor cells and promote the efficiency of gene therapy by adenovirus.

Oncolytic adenovirus delivering herpes simplex virus thymidine kinase suicide gene reduces the growth of human retinoblastoma in an in vivo mouse model.

Oncolytic conditionally replicating adenoviruses (CRAd) can exclusively replicate in and lyse tumor cells and are therefore promising tools in cancer therapy. In this study, we combined the oncolytic potential of a CRAd with its ability to deliver a suicide gene (herpes simplex virus thymidine kinase suicide gene, HSVtk) in order to further enhance tumor cell killing in a human retinoblastoma (RB) mouse model. We could demonstrate that CRAd driven by the human telomerase reverse transcriptase (hTERT) promoter and armed with the HSV thymidine kinase suicide gene/ganciclovir (HSVtk/GCV) could very effectively reduce growth of human RB in an orthotopic nude mouse model. These findings suggest that hTERT promoter-driven CRAd in combination with HSVtk/GCV gene therapy could be a promising new approach for the treatment of RB. In addition, we found that hTERT promoter-driven CRAd replication occurred exclusively in human RB cells but not in primary human retinal pigment epithelial cells (hRPE), indicating that application of hTERT promoter-driven CRAd for the treatment of RB would be safe.

Role of Zc3h12a in enhanced IL-6 production by newborn mononuclear cells in response to lipopolysaccharide.

BACKGROUND: The uncontrolled inflammatory response following infection is closely related to the morbidity and mortality of neonates. Interleukin 6 (IL-6) plays an important role in the pathogenesis and prognosis of this process. To better elucidate the secretion of IL-6 following infection in neonates, we investigated the IL-6 level and mechanism of IL-6/TLR4 signaling pathways. METHODS: We compared the IL-6, procalcitonin (PCT), and CRP levels between septic neonates and toddlers. In vitro cord blood samples from healthy term neonates and peripheral venous blood from healthy adult volunteers were collected. Protein expression was analyzed by Western blotting, mRNA expression by real-time PCR and membrane molecule expression by flow cytometry. RESULTS: The IL-6 concentrations were significantly higher in the neonate group than in the toddler group (p < 0.05). In the toddler group, the IL-6 concentrations were correlated positively with both PCT and CRP (PCT: r = 0.451, p = 0.001; CRP: r = 0.243, p = 0.023). In vitro, the secretion of IL-6 increased with the rising concentrations of LPS; at 1000 ng/ml LPS, IL-6 secretion from the monocytes of neonates was significantly higher than that of adults. There was a marked decreased level of MyD88 in neonate monocytes compared with that in adult monocytes. Additionally, the mRNA levels of Zc3h12a in neonate monocytes were significantly lower than those in adult monocytes following LPS stimulation. CONCLUSION: Neonates displayed enhanced IL-6 production after infection. Our study, for the first time, reported a significant decrease in the expression of Zc3h12a in neonates. Thus, Zc3h12a may be a key factor for the aberrant increase in IL-6 after neonate infection.

[Enhanced transduction efficiency of adeno-associated virus on cancer cells with the help of low dose adenovirus].

OBJECTIVE: To investigate whether adeno-associated virus (AAV) could enhance its infection efficiency on cancer cells when combined with non-replicable adenovirus (Ad-null) in vitro as well as in vivo and to study its underlying mechanisms. METHODS: AAV2 particle was added into NCI-H460 tumor cell lines alone or in combination with different amount of adenovirus. 1 to 7 days after transduction, cells were observed and recorded with fluorescence microscope, the expression levels of report gene EGFP in tumor cells were examined by using flow cytometry and Western blotting, the expression of report genes luciferase was analyzed with luminometer to obtain the relative light units. After the establishment of tumor model, the nude mouse were administrated with AAV2 or AAV2 + Ad-null in tumors, and then tested their infection efficiency and expression levels with roperscientific bioluminescence tumor imaging system. RESULTS: The results obtained with the help of flow cytometry and luciferase assay suggested that the infection efficiency of AAV2 was enhanced significantly when combined with low dose Ad-null in vitro, the infection efficiency of AAV2 alone was 6.4% and it reached 55.2% when combined with 10 MOI Ad-null, Western blotting assay demonstrated that the protein expression level of reporter gene in tumor cells enhanced when combined with 10 MOI Ad-null compared with AAV2 infection alone, and the enhancement of reporter gene expression was observed in a concentration-dependent manner; real-time PCR analysis confirmed that Ad-null enhanced the mRNA level of AAV2-EGFP but not the copies of genomic DNA of AAV2-EGFP. Ad-null significantly augmented the infection efficiency when tested on NCI-H460 tumor model. With the help of Ad-null, the signal of luciferin in nude mouse was 4.5 times more than that of control. CONCLUSION: The infection efficiency of AAV was enhanced significantly when combined with low dose Ad-null in vitro and in vivo, and it offers basis for further study of gene therapy by AAV.

[Transduction efficacy of recombinant type 1 and type 2 adeno-associated virus in the retinal cells].

OBJECTIVE: To investigate the transduction and gene expression of the recombinant adeno-associated viruses (rAAV) of the serotypes 1 and 2 in the retinal cells. METHODS: rAAV vectors of type 1 and type 2 encoding EGFP were infected into the cultured retinal pigmentary epithelium (RPE) cells of the line CRL-2302 and primarily cultured retinal neural cells from normal SD rats, and primarily cultured RPE cells from an adult cornea donor. The cultured RPE cells transduced by rAAV2-EGFP or rAAV2/1-EGFP were harvested at the 7 th and 14 th day after infection to be detected by fluorescence-activated cell sorter. The onset of EGFP gene expression and EGFP positive rate were detected by flow cytometry and fluorescence microscopy. Then, rAAV2/1-EGFP and rAAV2-EGFP were injected into the subretinal spaces of 32 SD rats to investigate the onset of EGFP fluorescence and its distribution in the fundus in vivo via fluorescence stereoscope. HE staining and immunohistochemistry were used to observe the infected cell type and immune response in the retina. RESULTS: The percentage of EGFP positive cells and mean intensity of EGFP fluorescence in the cells transduced by rAAV2-EGFP 7 and 14 days after transduction were 13.50% +/- 1.70% and 15.60% +/- 0.82%, and 2.75 +/- 0.12 and 3.80 +/- 0.72 respectively; and the EGFP positive cells and mean intensity of EGFP fluorescence in the cells transduced by rAAV2/1-EGFP were 1.09% +/- 0.5% and 1.98% +/- 0.45%, and 1.12 +/- 0.09 and 1.75 +/- 0.2 respectively. The EGFP fluorescence area in the retina were (5389 +/- 211) microm(2), (9832 +/- 364) microm(2), (14 454 +/- 446) microm(2), (20 528 +/- 648) microm(2), and (20 264 +/- 683) microm(2) respectively 3, 7, 14, and 75 days, and 4 month after transduction by rAAV2-EGFP in vivo; In the rat retina transduced by rAAV2/1-EGFP, the EGFP fluorescence areas were (9666 +/- 348) microm(2), (12 160 +/- 439) microm(2), (19 794 +/- 621) microm(2), (26 172 +/- 923) microm(2), and (26 022 +/- 965) microm(2) respectively 3, 7, 14, and 75 days, and 4 month after infection. CONCLUSION: rAAV2 efficiently transduces retinal cells both in vitro and in vivo. rAAV2/1 is a more effective gene-transferring vector to be used in retinal cells in vivo than rAAV2.

Clinical characteristics and genetic profiles of 174 patients with X-linked agammaglobulinemia: Report from Shanghai, China (2000-2015).

X-linked agammaglobulinemia (XLA) is a humoral primary immunodeficiency. XLA patients typically present with very low numbers of peripheral B cells and a profound deficiency of all immunoglobulin isotypes. Most XLA patients carry mutations in Bruton tyrosine kinase (BTK) gene.The genetic background and clinical features of 174 Chinese patients with XLA were investigated. The relationship between specific BTK gene mutations and severity of clinical manifestations was also examined. Mutations were graded from mild to severe based on structural and functional prediction through bioinformatics analysis.One hundred twenty-seven mutations were identified in 142 patients from 124 families, including 45 novel mutations and 82 recurrent mutations that were distributed over the entire BTK gene sequence. Variation in phenotypes was observed, and there was a tendency of association between genotype and age of disease onset.This report constitutes the largest group of patients with BTK mutations in China. A genotype-phenotype correlation was observed in this study. Early diagnosis of congenital agammaglobulinemia should be based on clinical symptoms, family history, and molecular analysis of the BTK gene.

[Inhibitation of tumor angiogenesis, growth and metastasis by blocking VEGF paracrine pathway].

Solid tumors require an adequate vascular supply to grow beyond a certain dimension. It is known that formation of new blood vessels in tumor is mediated by unbalanced expression of angiogenic factors and their inhibitors. Among the former, the vascular endothelial growth factor (VEGF) has been assumed prime candidacy as a major positive physiological effector. To investigate the role of VEGF in angiogenesis associated with development of breast cancer, a sense VEGF and an anti-sense VEGF expression plasmids were constructed, and then were introduced into a human breast carcinoma cell line, MCF-7, expressing middle level of endogenous VEGF. Anti-sense VEGF(121) transfected MCF-7 cells that expressed reduced constitutive levels of VEGF and showed the same growing potential as untransfected MCF-7 cells in vitro, but it showed longer latency, smaller tumor, slower growth and prolonged survival time compared to parental or sense VEGF(165) transfected MCF-7 cells in vivo. Moreover, the tumors derived from anti-sense VEGF(121) transfected MCF-7 cells characterized by minimal vascularization and extensive necrosis. Finally, mice with primary subcutaneous tumors treated with intratumoral administration of anti-sense VEGF, or the plasmid expressing extracellular domain of the Flk-1 VEGF receptor (sFlk-1) followed by electroporation, showed significant tumor suppression. These results suggest that VEGF plays a major angiogenic role in breast cancer and a strategy, which blocks the VEGF paracrine pathway, may provide a means to control tumor growth topically without the risk of systemic antiangiogenesis.

[Liposome-mediated gene transfer into retina].

OBJECTIVE: To evaluate the efficiency of liposome mediated gene transfer to retina, the time of gene expression in retinal cells, retinal damage caused by liposome and the possibility of using liposome mediated gene transfer to retina for treating fundus diseases. METHODS: The ratio of cationic liposome to green fluorescein protein (GFP) expression plasmid for high efficacy of transfection was tested in vitro. Then optimal liposome-plasmid mixture was injected into the subretinal space of Sprague-Dawley (SD) or Royal college of surgeon (RCS) rats. The GFP expression was observed by using fluorescence microscopy, and morphological changes were examined by using paraffin embedded sections, HE staining and transmission electron microscopy. RESULTS: The GFP expression in retinal cells was observed lasting more than 4 weeks. However, upon 4 weeks of transfection the swelling and degeneration in outer segment of photoreceptors could be observed. The aggravated degeneration with disappearance of outer segments, only one layer of photoreceptor nucleus surviving, apoptotic inner granular layer cells and neovascularization were observed 8 weeks after transfection. But no inflammatory cells were observed. Three of 5 RCS rats that received plasmid pCNTF (ciliary neurotrophic factor) delivery at 4 weeks old showed more surviving nuclei of photoreceptors after 3 to 5 weeks of transfection. CONCLUSION: Liposome is able to deliver genes to retinal cells with efficacy, and the expression of therapeutic gene such as CNTF in retinal cells can rescue photoreceptors from degeneration. But liposome used here is to some extent harmful to photoreceptors.

Dissecting the roles of E1A and E1B in adenoviral replication and RCAd-enhanced RDAd transduction efficacy on tumor cells.

Oncolytic viruses have recently received widespread attention for their potential in innovative cancer therapy. Many telomerase promoter-regulated oncolytic adenoviral vectors retain E1A and E1B. However, the functions of E1A and E1B proteins in the oncolytic role of replication-competent adenovirus (RCAd) and RCAd enhanced transduction of replication defective adenoviruses (RDAd) have not been addressed well. In this study, we constructed viruses expressing E1A alone, E1A plus E1B-19 kDa, and E1A plus E1B-19 kDa/55 kDa. We then tested their roles in oncolysis and replication of RCAd as well as their roles in RCAd enhanced transfection rate and transgene expression of RDAd in various cancer cells in vitro and in xenografted human NCI-H460 tumors in nude mice. We demonstrated that RCAds expressing E1A alone and plus E1B-19 kDa exhibited an obvious ability in replication and oncolytic effects as well as enhanced RDAd replication and transgene expression, with the former showed more effective oncolysis, while the latter exhibited superior viral replication and transgene promotion activity. However, RCAd expressing both E1A and E1B-19 kDa/55 kDa was clearly worst in all these abilities. The effects of E1A and E1B observed through using RCAd were further validated by using plasmids expressing E1A alone, E1A plus E1B-19 kDa, and E1A plus E1B-19 kDa/55 kDa proteins. Our study provided evidence that E1A was essential for inducing replication and oncolytic effects of RCAd as well as RCAd enhanced RDAd transduction, and expression of E1B-19 kDa other than E1B-55 kDa could promote these effects. E1B-55 kDa is not necessary for the oncolytic effects of adenoviruses and somehow inhibits RCAd-mediated RDAd replication and transgene expression.

Pharmacokinetics of combined gene therapy expressing constitutive human GM-CSF and hyperthermia-regulated human IL-12.

BACKGROUND: An adenovirus that expresses both interleukin (IL)-12 and granulocyte-macrophage colony-stimulating-factor (GM-CSF) has been proven to be very effective in treating several tumors, but causes serious normal tissue toxicities. METHODS: In this study, a novel adenoviral vector was constructed by placing the human GM-CSF gene under the control of the CMV-IE promoter and human IL-12 gene under the control of heat shock protein 70B gene promoter. Both hGM-CSF and hIL-12 expressions in virus-infected tumor cells were analyzed in vitro and in vivo when underlying single or multiple rounds of hyperthermia. RESULTS: We observed constitutive high expression of human GM-CSF and heat-induced expression of human IL-12 after a single round of hyperthermia post viral infection. The heat-induced hIL-12 expression exhibited a pulse-like pattern with a peak at 24 hrs followed by a decline 48 hrs post heat stress. Repeated heat treatment was more effective in inducing hIL-12 expression than a one-time heat treatment. Interestedly, we also observed that constitutive expression of hGM-CSF could be stimulated by heat stress in tested tumor cells. CONCLUSION: Our study provided a novel strategy for combined gene therapy that allows constitutive expression of a non-toxic gene such as GM-CSF and heat-induced expression of a toxic gene such as IL-12. In addition, our study also showed that hyperthermia can be used to trigger gene expression in temporal and special manner.

Combination of oncolytic adenovirus and endostatin inhibits human retinoblastoma in an in vivo mouse model.

There is a critical need for new paradigms in retinoblastoma (RB) treatment that would more efficiently inhibit tumor growth while sparing the vision of patients. Oncolytic adenoviruses with the ability to selectively replicate and kill tumor cells are a promising strategy for cancer gene therapy. Exploration of a novel targeting strategy for RB utilizing combined oncolytic adenovirus and anti-angiogenesis therapy was applied over the course of the current study with positive results. The oncolytic adenoviruses Ad-E2F1 p-E1A and Ad-TERT p-E1 were constructed. The E1 region was regulated by the E2F-1 promoter or the human telomerase reverse transcriptase (hTERT) promoter, respectively. Effects on both replication and promotion of enhanced green fluorescent protein (EGFP) expression were observed in the replication-defective adenovirus Ad-EGFP in diverse cancer cell lines, HXO-RB44, Y79, Hep3B, NCIH460, MCF-7 and HLF. The cancer cell death induced by these agents was also explored. The in situ RB model demonstrated that mice with tumors treated with the oncolytic adenovirus and replication-defective adenovirus Ad-endostatin exhibited notable cancer cell death. This anticancer effect was further examined by stereo microscope, and the survival rate of experimental mice was determined. Both Ad-E2F1 p-E1A and Ad-TERT p-E1 replicated specifically in cancer cells in vitro and promoted EGFP expression in Ad-EGFP, although Ad-E2F1 p-E1A demonstrated superior EGFP promotion activity than Ad-TERT p-E1. In Hep3B, NCIH460 and MCF-7 cells, the number of Ad-TERT p-E1 copies was observed to exceed of the number of Ad-E2F1 p-E1A copies by a minimum of 10-fold. Furthermore, Ad-TERT p-E1 demonstrated significantly superior oncolytic effects in the RB mouse model, and Ad-endostatin effectively suppressed tumor growth and extended the overall lifespan of subjects; however, the Ad-E2F1 p-E1A was clearly less effective in attaining these goals. Most notably, the antitumor effect and survival rate of subjects in the combined Ad-TERT p-E1 + Ad-endostatin group were higher than those treated with either single Ad-TERT p-E1 (p=0.097, p=0.022, respectively) or Ad-endostatin (p=0.037, p=0.006, respectively). In conclusion, application of transcription factor E2F-1 and human telomerase reverse transcriptase (hTERT) promoters to control E1 offer some guarantee that not only is RB gene therapy effective, but it is also safe. Combination therapy using the oncolytic adenovirus Ad-TERT p-E1 and replication-defective adenovirus Ad-endostatin demonstrates desirable oncolysis in the in situ RB mouse model. Additionally, E1B19K is important in the RB tumor suppression effect of oncolytic adenoviruses.

Effects of tumor microenviromental factors on VEGF expression.

The expression of vascular endothelial growth factor (VEGF) is regulated by microenvironmental factors within the tumors, such as hypoxia, free radicals, pH imbalance and nutrient deficiency. The purpose of this study was to observe VEGF activity in tumor cells under different stress conditions. A plasmid was generated, consisting of green fluorescent protein (GFP) fused to a 1,217-bp sequence, which was located downstream and upstream of the transcriptional start site of VEGF, respectively. The plasmid was stably transfected into 4T1 mouse breast carcinoma cells. Cells were cultured in a medium with nitric oxide (NO) donor sodium nitroprusside (SNP), hypoxia-mimetic agent deferoxamine mesylate (DFX), H2O2, absence of serum and lowered or elevated pH, or were heat-shocked, followed by measurement of VEGF activity by reverse transcription polymerase chain reaction (RT-PCR) and ELISA. Hypoxia, SNP and H2O2 led to increments of VEGF mRNA and protein expression, as well as of GFP expression. The pH alterations, serum deprivation and heat shock reduced VEGF mRNA expression, but had little effect on GFP expression. The results demonstrated that VEGF expression may be influenced by a number of microenvironmental factors and these factors may play important roles in regulating VEGF expression during tumorigenesis.