MBOAT1 homozygous missense variant causes nonobstructive azoospermia / 亚洲男科学杂志(英文版)

Nonobstructive azoospermia (NOA) is a common cause of infertility and is defined as the complete absence of sperm in ejaculation due to defective spermatogenesis. The aim of this study was to identify the genetic etiology of NOA in an infertile male from a Chinese consanguineous family. A homozygous missense variant of the membrane-bound O-acyltransferase domain-containing 1 (MBOAT1) gene (c.770C>T, p.Thr257Met) was found by whole-exome sequencing (WES). Bioinformatic analysis also showed that this variant was a pathogenic variant and that the amino acid residue in MBOAT1 was highly conserved in mammals. Quantitative polymerase chain reaction (Q-PCR) analysis showed that the mRNA level of MBOAT1 in the patient was 22.0% lower than that in his father. Furthermore, we screened variants of MBOAT1 in a broader population and found an additional homozygous variant of the MBOAT1 gene in 123 infertile men. Our data identified homozygous variants of the MBOAT1 gene associated with male infertility. This study will provide new insights for researchers to understand the molecular mechanisms of male infertility and will help clinicians make accurate diagnoses.

Un trastorno poco frecuente del ciclo de la urea en un recién nacido: deficiencia de N-acetilglutamato sintasa / A rare urea cycle disorder in a neonate: N-acetylglutamate synthetase deficiency

Los trastornos del ciclo de la urea (TCU) son enfermedades hereditarias con un posible desenlace desfavorable por hiperamoniemia grave. Se informa de una bebé con deficiencia de N-acetilglutamato sintasa (NAGS), quien tenía succión débil e hipotonicidad. Al examinarla, se observó hepatomegalia. El hemograma, los análisis y la gasometría eran normales, y las proteínas de la fase aguda, negativas. En los análisis, no se observaron cetonas en sangre, pero sí concentraciones elevadas de amoníaco. Las pruebas metabólicas no fueron concluyentes. Se inició el tratamiento de emergencia inmediatamente y recibió el alta el día 15 después del ingreso. Se confirmó deficiencia de NAGS mediante análisis de ADN. La paciente no tiene restricciones alimentarias ni toma medicamentos, excepto N-carbamil glutamato (NCG). La deficiencia de NAGS es el único TCU que puede tratarse específica y eficazmente con NCG. La detección temprana permite iniciar un tratamiento temprano y evitar los efectos devastadores de la hiperamoniemia

Urea cycle disorders (UCD), are genetically inherited diseases that may have a poor outcome due to to profound hyperammonemia. We report the case of a baby girl diagnosed as N-acetylglutamate synthase (NAGS) deficiency.The patient was evaluated due to diminished sucking and hypotonicity. Physical examination showed hepatomegaly. Complete blood count, biochemical values and blood gas analyses were normal, acute phase reactants were negative. Further laboratory analyses showed no ketones in blood and highly elevated ammonia. Metabolic tests were inconclusive. Emergency treatment was initiated immediately and she was discharged on the 15th day of admission. NAGS deficiency was confirmed by DNA-analysis. She is now without any dietary restriction or other medication, except N-carbamylglutamate (NCG).NAGS deficiency is the only UCD which can be specifically and effectively treated by NCG. Early recognition of disease will lead to early treatment that may prohibit devastating effects of hyperammonemia

Transgenesis of Drosophila melanogaster with an Elovl5 gene enables the production of longer-chain fatty acids / 生物工程学报

In most insects, polyunsaturated fatty acids (PUFAs) are mainly polyunsaturated fatty acids with a carbon-chain length less than 18 carbon atoms, hardly any long-chain polyunsaturated fatty acids such as C20 and C22 that are more valuable and bioactive. This study, by using Drosophila melanogaster (Fruit fly) as a model organism, optimized the Δ6-fatty acid elongase enzyme Elovl5 gene from mice and transferred it to fruit flies for expression. Vectors containing Elovl5 gene were successfully injected into drosophila embryo through the microscopic injection. There were enhanced green fluorescent proteins expressed in the whole developmental stage of Drosophila be means of fluorescence microscope. At the same time, expression of Elovl5 gene significantly contributed to the transformation of fruit flies C18-polyunsaturated fatty acids in the body towards the biosynthesis of longer-chain polyunsaturated fatty acids. The transgenic fruit fly model rich in long-chain polyunsaturated fatty acids such as C20 and C22 were obtained, providing a basis for further research on biosynthesis of polyunsaturated fatty acids in fruit flies.

Cloning and function analysis of elongase of very long chain fatty acid gene Bmelo424 in silkworm / 生物工程学报

Genes belonging to the elongases of very long chain fatty acid (ELOVL) family affect many physiological functions in organism. In this paper, Bmelo424 gene, a member of the ELOVL family in silkworm, was cloned and its ORF was 558 bp. Its protein sequence was predicted to have four transmembrane domains, six serine phosphorylation sites, eight threonine phosphorylation sites and four tyrosine phosphorylation sites, and its subcellular localization was in the endoplasmic reticulum. Secondary structure analysis showed that the percentage of alpha-helix and beta-strand was 26.7% and 20% respectively. The results of fluorescence quantitative PCR showed that Bmelo424 gene was expressed in all tissues of silkworm, especially with the highest expression in head. By heterologous expression of Bmelo424 gene in Saccharomyces cerevisiae, the effect of Bmelo424 gene on fatty acid elongation was studied. GC-MS results indicated that the fatty acid content of C16:1n-7 in S. cerevisiae with pYES2-Bmelo424 recombinant plasmid increased significantly, whereas the content of C16:0, C18:0 and C18:1n-9 decreased. The results of temperature stress revealed that Bmelo424 gene could improve the low temperature adaptability of S. cerevisiae, but its high temperature adaptability decreased. This provides a reference for exploring the function of Bmelo424 gene in silkworm.

K (lysine) acetyltransferase 2A affects the osteogenic differentiation of periodontal ligament stem cells through the canonical Wnt pathway / 华西口腔医学杂志

OBJECTIVE@#This study aims to investigate the mechanism of K (lysine) acetyltransferase 2A (KAT2A) regulation and control on the osteogenic differentiation of periodontal ligament stem cells (PDLSCs).@*METHODS@#The expression levels of KAT2A in PDLSCs were compared from each generation of the normal (H-PDLSCs) and periodontitis tissues (P-PDLSCs). The influences of KAT2A gene interference on the osteogenic differentiation of PDLSCs were also detected. In addition, the influences of the KAT2A gene interference to the canonical Wnt pathway and ligands were detected. The upstream and down-stream relationships between KAT2A and canonical Wnt pathway were also determined.@*RESULTS@#The decreased expression of KAT2A in PDLSCs from the inflammatory tissue in each generation was compared with that in PDLSCs from the healthy tissue, and the difference was statistically significant (P<0.05). When the KAT2A gene was disrupted, the osteogenesis ability of PDLSC was declined, and the difference was statistically significant (P<0.05). The canonical Wnt pathway was activated, and the antagonist Dickkopf-1 (DKK-1) was reduced. After the DKK-1 addition, the osteogenic differentiation of the disturbed PDLSCs was recovered, and KAT2A was unaffected.@*CONCLUSIONS@#The KAT2A expression in PDLSCs was decreased because of perio-dontitis. The classical Wnt pathway was activated to inhibit the osteogenic differentiation of the cells.

Genetic Variants in the ELOVL5 but not ELOVL2 Gene Associated with Polyunsaturated Fatty Acids in Han Chinese Breast Milk / 生物医学与环境科学（英文）

The present study was designed to examine the contributions of the fatty acid elongase (ELOVL) gene polymorphisms to the levels of polyunsaturated fatty acids (PUFAs) in breast milk. Two hundred and nine healthy Han Chinese mothers were included in the study. Carriers of minor alleles of SNPs (rs2397142 and rs9357760) in ELOVL5 were associated with higher levels of linoleic acid (LA), dihomo-γ-linolenic acid (DGLA), arachidonic acid (AA), docosatetraenoic acid (DTA), docosahexenoic acid (DHA), while in rs209512 of ELOVL5 the carriers of minor alleles had lower levels of DTA compared to major homozygote alleles (P ranged from 0.004-0.046), and genetically explained variability ranged from 3.2% for eicosapentaenoic acid (EPA) to 6.0% for LA. Our findings demonstrated that common variation in ELOVL5 gene encoding rate-limiting enzymes in the metabolism of PUFAs contribute to the PUFAs in breast milk.

Homocysteine induces glyceraldehyde-3-phosphate dehydrogenase acetylation and apoptosis in the neuroblastoma cell line Neuro2a

High plasma levels of homocysteine (Hcy) promote the progression of neurodegenerative diseases. However, the mechanism by which Hcy mediates neurotoxicity has not been elucidated. We observed that upon incubation with Hcy, the viability of a neuroblastoma cell line Neuro2a declined in a dose-dependent manner, and apoptosis was induced within 48 h. The median effective concentration (EC50) of Hcy was approximately 5 mM. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) nuclear translocation and acylation has been implicated in the regulation of apoptosis. We found that nuclear translocation and acetylation of GAPDH increased in the presence of 5 mM Hcy and that higher levels of acetyltransferase p300/CBP were detected in Neuro2a cells. These findings implicate the involvement of GAPDH in the mechanism whereby Hcy induces apoptosis in neurons. This study highlights a potentially important pathway in neurodegenerative disorders, and a novel target pathway for neuroprotective therapy.

Quinolonas: Perspectivas actuales y mecanismos de resistencia / Quinolones: Nowadays perspectives and mechanisms of resistance

Quinolones are a family of synthetic broad-spectrum antimicrobial drugs whose target is the synthesis of DNA. They directly inhibit DNA replication by interacting with two enzymes; DNA gyrase and topoisomerase IV. They have been widely used for the treatment of several community and hospital acquired infections, in the food processing industry and in the agricultural field, making the increasing incidence of quinolone resistance a frequent problem associated with constant exposition to diverse microorganisms. Resistance may be achieved by three non-exclusive mechanisms; through chromosomic mutations in the Quinolone Resistance-Determining Regions of DNA gyrase and topoisomerase IV, by reducing the intracytoplasmic concentrations of quinolones actively or passively and by Plasmid-Mediated Quinolones-Resistance genes, [Qnr determinant genes of resistance to quinolones, variant gene of the aminoglycoside acetyltransferase (AAC(6')-Ib-c)] and encoding genes of efflux pumps (qepA and oqxAB)]. The future of quinolones is uncertain, however, meanwhile they continue to be used in an irrational way, increasing resistance to quinolones should remain as an area of primary priority for research.

Las quinolonas son un grupo de antimicrobianos sintéticos de amplio espectro, cuyo objetivo es la síntesis del ADN. Inhiben directamente su replicación al interactuar con dos enzimas; ADN girasa y topoisomerasa IV. Se han utilizado ampliamente para el tratamiento de infecciones intra y extra-hospitalarias, en el campo de la agricultura y en el procesamiento de alimentos, lo que hace que el incremento de resistencia a quinolonas sea un problema cada vez más frecuente, asociado a la constante exposición de diversos microorganismos. La resistencia puede alcanzarse mediante tres mecanismos no excluyentes entre sí; a través de mutaciones cromosómicas en genes codificantes que afectan las regiones determinantes de resistencia a quinolonas de ADN girasa y topoisomerasa IV, al reducir las concentraciones intracitoplásmicas de quinolonas de manera activa o pasiva y por genes de resistencia a quinolonas mediados por plásmidos [genes de resistencia a quinolonas determinates de qnr, gen variante de la aminoglucósido acetil transferasa (AAC(6’)-lb-cr) y genes codificadores de bombas de eflujo (qepAy oqxAB)]. El futuro de las quinolonas es incierto; sin embargo, mientras continúen empleándose para el manejo de infecciones en el ser humano, el incremento de resistencia a quinolonas debe permanecer como un área de importancia primaria para la investigación.

Effect of Tip30 expression on the invasion and metastasis of hepatoma cells / 中南大学学报(医学版)

OBJECTIVE@#To investigate the effect of Tip30 on the invasion and metastasis of hepatoma cells.@*METHODS@#Recombinant plasmid pAAV-Tip30 was transfected to HepG2 cells by polylactic-coglycolic acid (PLGA) nanoparticles. RT-PCR was used to detect the mRNA expression of matrix metalloproteinases (MMP)-2, MMP-9 and epidermal growth factor receptor (EGFR). MMP- 2 and MMP-9 protein level in the tumor tissue was detected by Western blot. The proliferation, of hepatoma cells was evaluated by MTS assay and clone formation method. The adhesion and invasion of hepatoma cells were evaluated by adhesion assay and Transwell migration assay, respectively.@*RESULTS@#With RT-PCR and Western blot, we found Tip30 decreased the expression of MMP-2 and MMP-9. MTS assay and cell clone formation method showed inhibited proliferation of the HepG2 cells. Chemo invasion assays showed that Tip30 decreased the invasiveness of hepatoma cells. Tip30 attenuated the binding of liver cancer cell line to human umbilical vein endothelial cells and fibronectin.@*CONCLUSION@#The invasion and metastasis of hepatoma cells can be inhibited by Tip30 gene in vitro.

Roles of Protein Arginine Methyltransferases in the Control of Glucose Metabolism

Glucose homeostasis is tightly controlled by the regulation of glucose production in the liver and glucose uptake into peripheral tissues, such as skeletal muscle and adipose tissue. Under prolonged fasting, hepatic gluconeogenesis is mainly responsible for glucose production in the liver, which is essential for tissues, organs, and cells, such as skeletal muscle, the brain, and red blood cells. Hepatic gluconeogenesis is controlled in part by the concerted actions of transcriptional regulators. Fasting signals are relayed by various intracellular enzymes, such as kinases, phosphatases, acetyltransferases, and deacetylases, which affect the transcriptional activity of transcription factors and transcriptional coactivators for gluconeogenic genes. Protein arginine methyltransferases (PRMTs) were recently added to the list of enzymes that are critical for regulating transcription in hepatic gluconeogenesis. In this review, we briefly discuss general aspects of PRMTs in the control of transcription. More specifically, we summarize the roles of four PRMTs: PRMT1, PRMT 4, PRMT 5, and PRMT 6, in the control of hepatic gluconeogenesis through specific regulation of FoxO1- and CREB-dependent transcriptional events.

The role of histone H3 acetylation on cleft palate in mice induced by 2, 3, 7, 8-tetrachlorodibenzopdioxin / 中华整形外科杂志

<p><b>OBJECTIVE</b>To explore the role of histone H3 acetylation in cleft palate induced by 2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin (TCDD) in C57BL/6J mice, and its mechanism.</p><p><b>METHODS</b>On gestation day 10 (GD10), 36 pregnant mice were randomly divided into two groups as the treated group(n = 18) and the control group( n = 18). The mice in the treated group received intragastric administration with TCDD 28 μg/kg, while the mice in the control group received equivalent corn oil. The pregnant mice were sacrificed on GD13. 5, GD14. 5 and GD15. 5, collecting fetal palates to determine the activities of histone acetyltransferases (HATs) by Colorimetric and the expression level of acetylated histone H3 (Acetylated histone H3, Ac-H3) by Western-blot.</p><p><b>RESULTS</b>The activity of HATs was 0.409 7 ± 0.0147, 0.522 3 ± 0.017 1 and 0.643 5 ± 0.013 9 in control group on GD13.5, GD14.5 and GD15.5; 0.865 0 ± 0.0129, 0.719 1 ± 0.017 8 and 0.551 2 ± 0.016 8 in TCDD group. The activity of HATs in TCDD group was higher than that in control group on GD13. 5, GD14. 5, showing significantly difference between the two groups (t = - 56. 932, t = - 19. 516, P < 0.01); however, the activity of HATs in TCDD group was significantly lower than that in control group on GD15. 5 (t = 10. 382, P < 0.01). The expression level of Ac-H3 was 0.745 0 ± 0.113 5, 1.055 9 ± 0.249 4 and 1.795 5 ± 0.081 9 in control group on GD13. 5, GD14. 5 and GD15. 5; while 1.4490 ± 0. 1460, 1. 641 8 ± 0.099 7 and 1. 512 1 ± 0. 150 2 in TCDD group. The expression of Ac-H3 in TCDD group was higher than that in control group on GD13. 5, GD14. 5, showing significantly difference( t = -6. 593, -3. 779, P <0. 01, P <0.05) ; However, the expression of Ac-H3 in TCDD group was statistically lower than that in control group (t = 2. 870, P <0. 05).</p><p><b>CONCLUSION</b>The acetylation of histone H3 was involved in the cleft palate of C57BL/6J mice induced by TCDD, which may be one of the mechanisms in TCDD-induced cleft palate.</p>

Overexpression of four fatty acid synthase genes elevated the efficiency of long-chain polyunsaturated fatty acids biosynthesis in mammalian cells / 生物工程学报

Three long-chain polyunsaturated fatty acids, docosahexaenoic acid (DHA, 22:6n-3), eicosapentaenoic acid (EPA, 20:5n-3) and arachidonic acid (ARA, 20:4n-6), are the most biologically active polyunsaturated fatty acids in the body. They are important in developing and maintaining the brain function, and in preventing and treating many diseases such as cardiovascular disease, inflammation and cancer. Although mammals can biosynthesize these long-chain polyunsaturated fatty acids, the efficiency is very low and dietary intake is needed to meet the requirement. In this study, a multiple-genes expression vector carrying mammalian A6/A5 fatty acid desaturases and multiple-genes expression vector carrying mammalian Δ6/Δ5 fatty acid desaturases and Δ6/Δ5 fatty acid elongases coding genes was used to transfect HEK293T cells, then the overexpression of the target genes was detected. GC-MS analysis shows that the biosynthesis efficiency and level of DHA, EPA and ARA were significantly increased in cells transfected with the multiple-genes expression vector. Particularly, DHA level in these cells was 2.5 times higher than in the control cells. This study indicates mammal possess a certain mechanism for suppression of high level of biosynthesis of long chain polyunsaturated fatty acids, and the overexpression of Δ6/Δ5 fatty acid desaturases and Δ6/Δ5 fatty acid elongases broke this suppression mechanism so that the level of DHA, EPA and ARA was significantly increased. This study also provides a basis for potential applications of this gene construct in transgenic animal to produce high level of these long-chain polyunsaturated fatty acid.

Genetic analysis of the ELOVL6 gene polymorphism associated with type 2 diabetes mellitus

Recent animal studies have indicated that overexpression of the elongation of long-chain fatty acids family member 6 (Elovl6) gene can cause insulin resistance and β-cell dysfunction. These are the major factors involved in the development of type 2 diabetes mellitus (T2DM). To identify the relationship between single nucleotide polymorphisms (SNP) of ELOVL6 and T2DM pathogenesis, we conducted a case-control study of 610 Han Chinese individuals (328 newly diagnosed T2DM and 282 healthy subjects). Insulin resistance and islet first-phase secretion function were evaluated by assessment of insulin resistance in a homeostasis model (HOMA-IR) and an arginine stimulation test. Three SNPs of the ELOVL6 gene were genotyped with polymerase chain reaction-restriction fragment length polymorphism, with DNA sequencing used to confirm the results. Only genotypes TT and CT of the ELOVL6 SNP rs12504538 were detected in the samples. Genotype CC was not observed. The T2DM group had a higher frequency of the C allele and the CT genotype than the control group. Subjects with the CT genotype had higher HOMA-IR values than those with the TT genotype. In addition, no statistical significance was observed between the genotype and allele frequencies of the control and T2DM groups for SNPs rs17041272 and rs6824447. The study indicated that the ELOVL6 gene polymorphism rs12504538 is associated with an increased risk of T2DM, because it causes an increase in insulin resistance.

The First Korean Case of Mucopolysaccharidosis IIIC (Sanfilippo Syndrome Type C) Confirmed by Biochemical and Molecular Investigation

Mucopolysaccharidosis (MPS) III has 4 enzymatically distinct forms (A, B, C, and D), and MPS IIIC, also known as Sanfilippo C syndrome, is an autosomal recessive lysosomal storage disease caused by a deficiency of heparan acetyl-CoA:alpha-glucosaminide N-acetyltransferase (HGSNAT). Here, we report a case of MPS IIIC that was confirmed by molecular genetic analysis. The patient was a 2-yr-old girl presenting with skeletal deformity, hepatomegaly, and delayed motor development. Urinary excretion of glycosaminoglycan (GAG) was markedly elevated (984.4 mg GAG/g creatinine) compared with the age-specific reference range (A (IVS2+1G>A) and c.1150C>T (p.Arg384*). To the best of our knowledge, this is the first case of MPS IIIC to be confirmed by clinical, biochemical, and molecular genetic findings in Korea.

Effects of 5-Aza-dC on 5-Fu chemosensitivity by modulating TIP30 gene expression in human colorectal cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the effect of 5-Aza-2'-deoxycytidine (5-Aza-dC) on TIP30 gene expression and the relationship between TIP30 expression and the sensitivity to 5-fluouracil (5-Fu) in colorectal cancer cells.</p><p><b>METHODS</b>The methylation profile of TIP30 gene in HCT116 colorectal cancer cells was determined by methylation-specific PCR. The levels of TIP30 mRNA and protein were determined by RT-PCR and Western blot after the 5-Aza-dC treatment. MTT assay was used to detect the chemosensitivity of HCT116 cells to 5-Fu.</p><p><b>RESULTS</b>TIP30 gene displayed complete DNA methylation in the HCT116 cells without 5-Aza-dC pretreatment. After the 5-Aza-dC treatment for 3 days, only demethylating PCR amplification product was detected and TIP30 gene showed DNA demethylation. With the prolongation of the time of removal of 5-Aza-dC treatment, methylated and demethylated PCR amplification products were observed and TIP30 gene displayed both DNA methylation and DNA demethylation in the colorectal cancer cells. At the day 10 after removal of 5-Aza-dC, methylating PCR amplification product appeared and TIP30 gene showed DNA methylation. No expressions of TIP30 mRNA and protein were detected in the HCT116 cells untreated with 5-Aza-dC. After the treatment of 5-Aza-dC for 3 d and then removed the 5-Aza-dC, the expressions of TIP30 mRNA and protein were increased obviously. With the prolonged time after 5-Aza-dC removal, the expressions of TIP30 mRNA and protein decreased and reached the lowest level on day 10. The IC50 values of 5-Fu were 41.62, 33.17 and 4.96 µg/ml in the HCT116 cells pretreated with 5-Aza-dC, d0 and d10 with the drug removal after drug treatment for 3 d, respectively.</p><p><b>CONCLUSIONS</b>The results of this study show that the expression of TIP30 gene may be associated with its DNA methylation status and may affect the sensitivity of colorectal cancer cells to 5-Fu.</p>

The first report of the qnrB19, qnrS1 and aac(6´)-Ib-cr genes in urinary isolates of ciprofloxacin-resistant Escherichia coli in Brazil

In this study, we investigated the presence of plasmid-mediated quinolone resistance (PMQR) genes among 101 ciprofloxacin-resistant urinary Escherichia coli isolates and searched for mutations in the quinolone-resistance-determining regions (QRDRs) of the DNA gyrase and topoisomerase IV genes in PMQR-carrying isolates. Eight isolates harboured the qnr and aac(6')-Ib-cr genes (3 qnrS1, 1 qnrB19 and 4 aac(6')-Ib-cr). A mutational analysis of the QRDRs in qnr and aac(6')-Ib-cr-positive isolates revealed mutations in gyrA, parC and parE that might be associated with high levels of resistance to quinolones. No mutation was detected in gyrB. Rare gyrA, parC and parE mutations were detected outside of the QRDRs. This is the first report of qnrB19, qnrS1 and aac(6')-Ib-cr -carrying E. coli isolates in Brazil.

Clinical significance of CC3/TIP30 expression in breast carcinoma and its correlation with HER-2/neu / 中华外科杂志

<p><b>OBJECTIVE</b>To explore the clinical significance of CC3/TIP30 protein's expression in breast carcinoma and its correlation with HER-2/neu.</p><p><b>METHODS</b>The expression of CC3/TIP30 and HER-2/neu protein was detected in 112 breast cancer tissues which was collected from January 2004 to January 2005 by immunohistochemistry and the relationship with clinic pathological parameters and prognosis was analyzed. Small interfering RNA (siRNA) which target to knock out CC3/TIP30 were transfected into SK-BR-3 cells. Real-time PCR were used to detect the level of CC3/TIP30 and HER-2/neu mRNA.</p><p><b>RESULTS</b>The results of immunohistochemistry showed CC3/TIP30 protein was correlated with TNM stage, lymph node status, HER-2 status and molecule classification (P = 0.048, 0.019, 0.027, 0.011), but there was no association with age, tumor size, estrogen receptor and progesterone receptor. Real-time PCR results revealed that CC3/TIP30 siRNA down-regulation the level of its mRNA, accompanied by a decline in the expression of HER-2/neu gene mRNA, the difference was statistically significant (F = 56.797, P = 0.000; F = 165.101, P = 0.000). In addition, Kaplan-Meier curves of disease-specific survival analysis showed a marked difference in the subtype of HER-2 protein positive between CC3/TIP30 positive group and negative group (χ(2) = 10.732, P = 0.001).</p><p><b>CONCLUSIONS</b>The loss of CC3/TIP30 is related to occurrence and development in breast cancer, suggesting early onset of metastasis and recurrence. Perhaps CC3/TIP30 can be considered as a sub-typing indicator in HER-2 positive breast cancer.</p>

Acetylsalicylic acid strengthens the effects of ANISpm against hepatocellular carcinoma and its molecular mechanism / 药学学报

The objective of this study is to examine the effects of ANISpm, a novel polyamine naphthalimide conjugate, with acetylsalicylic acid against hepatocellular carcinoma in vivo and in vitro and elucidate its potential molecular mechanism. The proliferation inhibition was detected by MTT assay. Cell apoptosis, intracellular fluorescence intensity and mitochondrial membrane potential (MMP) were detected by high content screening (HCS) analysis. Polyamines content was analyzed by reverse-phase high performance liquid chromatography Protein expression levels were quantified by Western blotting assay. The combination treatment strongly inhibited cell proliferation, induced cell apoptosis in HepG2 cells and H22 hepatoma cells, which was mediated by enhanced ANISpm uptake via up-regulation of spermidine/spermine N1-acetyltransferase (SSAT) and depression of intracellular polyamine. Furthermore, this synergistic apoptosis was involved in mitochondria and death-receptor signal pathway. All these findings demonstrated that the combination treatment with acetylsalicylic acid and ANISpm resulted in synergistic antitumor effects on hepatoma cells. Thus, combination therapy with these agents may be useful as a potential template for the development of better chemotherapeutic strategy against hepatoma.

Effect of overexpression of malate dehydrogenase on succinic acid production in Escherichia coli NZN111 / 生物工程学报

Escherichia coli NZN111 is a double mutant with lactate dehydrogenase (ldhA) and pyruvate formate-lyase (pflB) inactivated. Under anaerobic conditions, disequilibrium of coenzyme NADH and NAD+ causes Escherichia coli NZN111 losing the glucose utilizing capability. In this study, we constructed a recombinant strain E. coli NZN111/pTrc99a-mdh and overexpressed the mdh gene with 0.3 mmol/L of IPTG under anaerobic fermentation condition in sealed bottles. The specific malate dehydrogenase (MDH) activity in the recombinant strain was 14.8-fold higher than that in E. coli NZN111. The NADH/ NAD+ ratio decreased from 0.64 to 0.26 and the concentration of NAD+ and NADH increased 1.5-fold and 0.2-fold respectively. Under anaerobic conditions, the recombinant strain possessed the capability of growth and glucose absorption. We took dual-phase fermentation for succinate production. After the dry cell weight (DCW) reached 6.4 g/L under aerobic conditions, the cell culture was changed to anaerobic conditions. After 15 h, 14.75 g/L glucose was consumed and succinic acid reached 15.18 g/L. The yield of succinic acid was 1.03 g/g Glu and the productivity of succinic acid was 1.012 g/(L x h).

Effect of overexpression of nicotinic acid phosphoribosyl transferase on succinic acid production in Escherichia coli NZN111 / 生物工程学报

Escherichia coli strain NZN111 is a promising candidate for the fermentative production of succinate. However, because lactate dehydrogenase and pyruvate formate lyase were inactivated in NZN111, this strain had an unbalanced NADH/NAD+ ratio and could not use glucose under anaerobic conditions. In this study, a recombinant strain E. coli NZN111/pTrc99a-pncB was constructed to overexpress the nicotinic acid phosphoribosyl transferase gene (pncB). Under anaerobic conditions with the addition of 0.5 mmol/L nicotinic acid and 0.3 mmol/L isopropyl beta-D-thiogalactopyranoside (IPTG), the specific nicotinic acid phosphoribosyl transferase (NAPRTase, EC 2.4.2.11) activity in the recombinant strain was 11-fold higher than that in E. coli NZN111, the concentration of NAD(H) was increased by 3.85-fold, especially the concentration of NAD+ was increased by 5.17-fold and NADH/NAD+ was decreased from 0.640 to 0.125. The recombinant strain regained the capability of growth and glucose utilization under anaerobic conditions.