[Effect of death decoy receptor 3 on prognosis of breast cancer and function of breast cancer cells in vitro].

Objective: To study the effect of death decoy receptor 3 on the prognosis of breast cancer and the invasive function of breast cancer cells in vitro. Methods: Expression of DcR3 were assessed qualitatively by Q-PCR to analyze the correlation in 115 mammary tissue samples with a 10-year median follow-up. The expression of DcR3 was examined in MCF7 and MDA-MB-231 cell lines using immunocytochemical staining and RT-PCR. DcR3 knock-down cell sub-lines were constructed. The effects of reduced DcR3 expression were observed by establishing invasion and migration models. Results: Patients were divided into the good prognosis group (n=81) and the poor prognosis group (n=26). The expression of DcR3 in the poor prognosis group (133 350+49 646 copies/50 ng RNA)was significantly higher than that in the good prognosis group (5 393+1 428 copies/50 ng RNA, P=0.020). DcR3 transcripts were found to be increased significantly in grade 2 cancers compared to well differentiated grade 1(82 844±34 068 copies/50 ng RNA, n=39,) vs (5 371±3 500 copies/50 ng RNA, n=20, P=0.029).The DcR3 gene of MCF7 cell line and MDA-MB-231 cell line were successfully knocked out and verified that DcR3 knockout. And the invasion and migration of MCF7 cells were inhibited (P=0.009, P=0.001). However, no significant difference was found in these two aspects of the MDA-MB-231 cell line (P=0.475, P=0.102). Conclusion: DcR3 promotes the capacity of invasion of breast cancer cells and plays an important role in the metastasis of breast cancer. DcR3 detection is helpful to the judgment about prognosis of breast cancer.

Rectal Temperature of Corpse and Estimation of Postmortem Interval.

ABSTRACT: Measurement of corpse temperature is mainly used for estimation of early postmortem interval, and rectal temperature is often used as a representative of body's core temperature in actual work because it is simple, quick and non-invasive. At present, the rectal temperature postmortem interval estimation method internationally accepted and widely used is HENSSGE's nomogram method, while many domestic scholars also deduced their own regression equations through a large number of case data. Estimation of postmortem interval based on rectal temperature still needs further study. The nomogram method needs to be optimized and extended, and quantification of its influencing factors needs to be dealt with more scientifically. There is still a lack of consensus on the probability and duration of the temperature plateau. There is no clear understanding of the probability and extent of the change in initial temperature caused by various causes. New methods and ideas enrich methodological research, but it still lacks systemicity and practicality. This article reviews the researches on estimation of postmortem interval based on rectal temperature in order to summarize the current situation of previous researches and seek new breakthrough points. Because the decline of body temperature can be easily influenced by many factors in vitro and vivo, and the influencing factors in different regions vary greatly, regionalization research and application may be a practical exploration to improve the accuracy of postmortem interval determination.

Effect of aerobic exercise on miRNA-TLR4 signaling in atherosclerosis.

Toll-like receptor 4 (TLR4)-tumor necrosis factor receptor 6 (TRAF6) signaling is activated in atherosclerosis (AS), inducing inflammatory mediators. Because miR-146a, a TLR4 microRNA (miRNA), can regulate TLR4 signaling during inflammatory responses, this study investigated the effects of aerobic exercise on TLR4-targeted miRNAs in AS. Apolipoprotein E-null mice fed a high-fat diet for 12 weeks were separated into 3 groups: (i) no treatment (AS), (ii) statin treatment (AD), or (iii) aerobic exercise (AE). Plaques and foam cells were observed in the untreated control and statin groups, respectively, but not in the AE group. Reduced angiotensin II (Ang II) and endothelin 1 (ET1) levels were observed in the AE group. Both treatment groups significantly altered the expression of inflammatory cytokine expression and reduced vascular TLR4 levels. Increased miR-146a and miR-126 and reduced miR-155 levels were observed in both treatment groups (all, P<0.001). miR-146a interacted with the 3' untranslated region of the TRAF6 gene, reducing its expression. Thus, aerobic exercise and statins may induce miR-146a expression, thereby reducing vascular TRAF and TLR4 signaling and vascular inflammatory injury in AS. Further analysis of this pathway may provide insight into the protective effects of aerobic exercise on vascular disease as well as new therapeutic targets.

Correlation between the NPPB gene promoter c.-1298 G/T polymorphism site and pulse pressure in the Chinese Han population.

The aim of this study was to investigate the correlation between the natriuretic peptide precursor B (NPPB) gene single nucleotide polymorphism (SNP) c.-1298 G/T and pulse pressure (PP) of the Chinese Han population and the association between genotype and clinical indicators of hypertension. Peripheral blood was collected from 180 unrelated patients with hypertension and 540 healthy volunteers (control group), and DNA was extracted to amplify the 5'-flanking region and 2 exons of the NPPB gene by polymerase chain reaction; the fragment was sequenced after purification. The clinical data of all subjects were recorded, the distribution of the NPPB gene c.-1298 G/T polymorphism was determined, and differences in clinical indicators between the two groups were evaluated. The mean arterial pressure PP, and creatinine levels were significantly higher in the hypertension group than in the control group (P<0.05), but no other clinical indicators differed between the groups. There were no significant differences in genotype frequency and distribution of the NPPB gene c.-1298 G/T polymorphism between the hypertension group and the control group (P>0.05); in the control group, the mean PP of individuals with the SNP c.-1298 GG genotype was greater than that of individuals with the GT+TT genotype (P<0.05). In conclusion, there was no significant correlation between the NPPB gene c.-1298 G/T polymorphism and the incidence of essential hypertension in the Han population; however, the PP of the SNP c.-1298 GG genotype was greater than that of the GT+TT genotype in the control group.

A case of accessory mammary cancer in a male patient and a literature review.

A 68-year-old Chinese male patient was referred to the present hospital because of a right axillary lump in May 2011. Physical examination showed a rigid movable mass measuring 35 mm in diameter in the right axilla. No mass was palpable in either breast. Mammograms were normal. Physical and imaging examination of the head and neck region, lung, and upper and lower gastrointestinal tract also revealed no evidence of a primary tumor. Ultrasonography and resonance imaging (MRI) revealed no evidence of tumors in the bilateral mammary glands. Fine needle histological biopsy for suspected malignancy was performed, and the patient underwent tumor resection with axillary lymph node dissection on Jun 2011. Moderately differentiated adenocarcinoma in ectopic breast tissue was diagnosed based on the pathologic result, the tumor was immunohistochemically positive for ER, PR, and HER-2.

Hexahydrated magnesium ions bind in the deep major groove and at the outer mouth of A-form nucleic acid duplexes.

Magnesium ions play important roles in the structure and function of nucleic acids. Whereas the tertiary folding of RNA often requires magnesium ions binding to tight places where phosphates are clustered, the molecular basis of the interactions of magnesium ions with RNA helical regions is less well understood. We have refined the crystal structures of four decamer oligonucleotides, d(ACCGGCCGGT), r(GCG)d(TATACGC), r(GC)d(GTATACGC) and r(G)d(GCGTATACGC) with bound hexahydrated magnesium ions at high resolution. The structures reveal that A-form nucleic acid has characteristic [Mg(H(2)O)(6)](2+)binding modes. One mode has the ion binding in the deep major groove of a GpN step at the O6/N7 sites of guanine bases via hydrogen bonds. Our crystallographic observations are consistent with the recent NMR observations that in solution [Co(NH(3))(6)](3+), a model ion of [Mg(H(2)O)(6)](2+), binds in an identical manner. The other mode involves the binding of the ion to phosphates, bridging across the outer mouth of the narrow major groove. These [Mg(H(2)O)(6)](2+)ions are found at the most negative electrostatic potential regions of A-form duplexes. We propose that these two binding modes are important in the global charge neutralization, and therefore stability, of A-form duplexes.

Preliminary crystallographic studies of lobster D-glyceraldehyde-3-phosphate dehydrogenase and the modified enzyme carrying the fluorescent derivative.

When the active-site carboxymethylated D-glyceraldehyde-3-phosphate dehydrogenase is irradiated with ultraviolet light in the presence of NAD+, a fluorescent NAD derivative that is covalently linked to the enzyme is obtained. A preliminary crystallographic study of this fluorescent derivative, as well as of the native and the carboxymethylated enzymes from Palinurus versicolor, showed that they are isomorphous and belong to space group C2 as reported for the native enzyme from Palinurus vulgaris. The three forms of the enzyme, although they have identical unit cell parameters, differ considerably in their diffraction patterns, indicating marked differences in conformation in spite of the fact that they differ chemically only in a restricted region around the active site.

Crystal structures of the chromosomal proteins Sso7d/Sac7d bound to DNA containing T-G mismatched base-pairs.

Sso7d and Sac7d are two small chromatin proteins from the hyperthermophilic archaeabacterium Sulfolobus solfataricus and Sulfolobus acidocaldarius, respectively. The crystal structures of Sso7d-GTGATCGC, Sac7d-GTGATCGC and Sac7d-GTGATCAC have been determined and refined at 1.45 A, 2.2 A and 2.2 A, respectively, to investigate the DNA binding property of Sso7d/Sac7d in the presence of a T-G mismatch base-pair. Detailed structural analysis revealed that the intercalation site includes the T-G mismatch base-pair and Sso7d/Sac7d bind to that mismatch base-pair in a manner similar to regular DNA. In the Sso7d-GTGATCGC complex, a new inter-strand hydrogen bond between T2O4 and C14N4 is formed and well-order bridging water molecules are found. The results suggest that the less stable DNA stacking site involving a T-G mismatch may be a preferred site for protein side-chain intercalation.

Analyses of the stability and function of three surface mutants (R82C, K69H, and L32R) of the gene V protein from Ff phage by X-ray crystallography.

The high-resolution crystal structure of the gene V protein (GVP) from the Ff filamentous phages (M13, fl, fd) has been solved recently for the wild-type and two surface mutant (Y41F and Y41H) proteins, leading to a plausible model for the polymeric GVP-ssDNA complex (Guan Y, Zhang H, Wang AHJ, 1995, Protein Sci 4:187-197). The model of the complex shows extensive contacts between neighboring dimer GVPs involving electrostatic interactions between the K69 from one and the D79 and R82 from the next dimer. In addition, hydrophobic interactions between the amino acids L32 and L44 from one and G23 from the next dimer also contribute to the dimer-dimer interactions. Mutations at the L32, K69, and R82 amino acid sites generally destabilize the protein and many of these affect the function of the phage. We have studied the structural effects of three mutant proteins involving those sites, i.e., L32R, K69H, and R82C, by X-ray crystallographic analysis at 2.0 A resolution. In L32R GVP, the structural perturbation is localized, whereas in K69H and R82C GVPs, some long-range effects are also detected in addition to the local perturbation. We have interpreted the protein stability and the functional properties associated with those mutations in terms of the observed structural perturbations.

Cyclic diguanylic acid behaves as a host molecule for planar intercalators.

Cyclic ribodiguanylic acid, c-(GpGp), is the endogenous effector regulator of cellulose synthase. Its three-dimensional structure from two different crystal forms (tetragonal and trigonal) has been determined by X-ray diffraction analysis at 1 A resolution. In both crystal forms, two independent c-(GpGp) molecules associate with each other to form a self-intercalated dimer. A hydrated cobalt ion is found to coordinate to two N7 atoms of adjacent guanines, forcing these two guanines to destack with a large dihedral angle (32 degrees), in the dimer of the tetragonal form. This metal coordination mechanism may be relevant to that of the anticancer drug cisplatin. Moreover, c-(GpGp) exhibits unusual spectral properties not seen in any other cyclic dinucleotide. It interacts with planar organic intercalator molecules in ways similar to double helical DNA. We propose a cage-like model consisting of a tetrameric c-(GpGp) aggregate in which a large cavity ('host') is generated to afford a binding site for certain planar intercalators ('guests').

R and S enantiomers of 11-hydroxy- and 10,11-dihydroxy-N-allylnoraporphine: synthesis and affinity for dopamine receptors in rat brain tissue.

The R-(-)- and S-(+)-enantiomers of 11-hydroxy-N-allyl (4), and 10,11-dihydroxy-N-allyl (3) congeners of 11-hydroxy-N-n-propylnorapomorphine (11-OH-NPa, 2) or N-n-propylnorapomorphine (NPA, 1) were synthesized. Binding affinity of these compounds at dopamine (DA) receptor sites was evaluated with a membrane preparation of corpus striatum from rat brain. The R/S enantiomeric receptor affinity ratio was enhanced by allylic substitution of 3 and 4 and their R isomers had high DA receptor affinity similar to that of the N-n-propyl congeners. These N-allylnoraporphines are proposed as useful precursors to the preparation of their tritiated N-n-propyl enantiomers.

Synthesis and dopamine receptor affinities of enantiomers of 2-substituted apomorphines and their N-n-propyl analogues.

Syntheses of (R)-(-)-2-methoxyapomorphine (R-8), its antipode S-8, and its (R)-(-)-N-n-propyl R-9 derivatives are described. The dopaminergic receptor affinities of these compounds and their 2-unsubstituted counterparts (R)-(-)-apomorphine (R(-)-APO, R-1), (S)-(+)-apomorphine (S(+)-APO, S-1), and (R)-(-)-N-n-propylnorapomorphine (R(-)-NPA, R-2), as well as those of (R)-(-)-2-chloroapomorphine (R(-)-2-Cl-APO, R-6), (R)-(-)-2-bromoapomorphine (R(-)-2-Br-APO, R-6), were determined with tissue membrane preparations of corpus striatum from rat brain. Contribution of both an N-n-propyl and a 2-hydroxy in (R)-(-)-2-hydroxy-N-n-propylnorapomorphine (R(-)-2-OH-NPA, R-7) or a methoxy group in (R)-(-)-2-methoxy-N-n-propylnorapomorphine (R(-)-2-OCH3-NPA, R-9) produced the highest D2 affinity (0.053 and 0.17 nM) and D2 over D1 selectivity (17,300 and 10,500 times) of the compounds evaluated. The structure-affinity relationships of these 2-substituted aporphines suggest that secondary binding sites of D2 receptors interact with 2-substituents on the A ring of aporphines through H-bonding.

Synthesis, ligand binding, QSAR, and CoMFA study of 3 beta-(p-substituted phenyl)tropane-2 beta-carboxylic acid methyl esters.

A series of 3 beta-(p-substituted phenyl)tropane-2 beta-carboxylic acid methyl esters (2) were synthesized and found to possess high affinity for the cocaine binding site in rat striatum. The p-chloro (2c) and p-iodo (2n) compounds, which were the most potent analogues prepared, were found to be 85 and 78 times more potent than (-)-cocaine. The p-bromo (2m) and p-methyl (2d) were also 56 and 60 times more potent than cocaine. QSAR and CoMFA studies were conducted to correlate binding affinity of the cocaine analogues with their structural features. Whereas the QSAR study gave relatively low correlations, the CoMFA study gave a correlation with high predictive value.

2 beta-substituted analogues of cocaine. Synthesis and inhibition of binding to the cocaine receptor.

The potencies of a series of 2 beta-substituted cocaine analogues to displace [3H]-3 beta-(p-fluorophenyl)tropane-2 beta-carboxylic acid methyl ester binding in rat striatal membranes demonstrate the requirement for a 2 beta-substituent with two hydrogen-bond acceptors. The insensitivity of the ester moiety to steric and electronic factors suggests its modification to provide site-specific irreversible ligands.

Synthesis and structural requirements of N-substituted norapomorphines for affinity and activity at dopamine D-1, D-2, and agonist receptor sites in rat brain.

A series of N-substituted analogues of (R)-(-)-norapomorphine were synthesized to study the optimal structural requirements of the N-alkyl side chain to interact with D-1 and D-2 dopaminergic receptors as well as dopamine (DA) agonist binding sites. Evaluations included testing the affinity of these compounds for DA receptor sites in rat striatal tissue and assessing stereotypy as a behavioral index of dopaminergic activity. The electronic, steric, and lipophilic properties of the N-alkyl side chain were found to be related to affinity, D-2 selectivity, and dopaminergic activity. All 11 compounds evaluated had relatively low affinity at D-1 sites. Optimum D-2 and agonist-site affinity as well as agonist activity were exhibited by N-cyclopropylmethyl (7) greater than or equal to N-allyl (8) greater than or equal to N-propyl (4) or N-ethyl (3) substituted compounds. Branching of the N-alkyl side chain as in N-isopropyl (5) and N-isobutyl (6) markedly reduced the D-2 affinity and activity, presumably due to steric effects. The N-trifluoroethyl (10) and N-pentafluoropropyl (11) derivatives had low affinity for all their dopamine receptor sites and no agonistic activity; evidently, the highly electronegative F atoms decrease basicity of the N atom and therefore decrease the ability of the N atom to be cationic at physiological pH, a proposed requirement for high-affinity binding to DA receptors.

Effects of isomers of hydroxyaporphines on dopamine metabolism in rat brain regions.

The effects of isomers of di- and monohydroxyaporphines on cerebral dopamine (DA) metabolism were evaluated in representative extrapyramidal (corpus striatum) and limbic (nucleus accumbens septi) tissues of rat brain by three methods: (1) changes in the ratio of homovanillic acid (HVA) to DA, (2) accumulation of L-dihydroxyphenylalanine (DOPA) after inhibiting its decarboxylation to DA under "open-loop" conditions, as well as (3) after gamma-butyrolactone (GBL) pretreatment to provide selective effects at presynaptic DA autoreceptors. The DA-agonist R(-) isomers of the aporphines apomorphine (APO), N-n-propylnorapomorphine (NPA), and 11-hydroxy-N-n-propylnoraporphine (11-OH-NPa) showed consistent dose-dependent inhibition of DA synthesis in both brain regions with all models; the neuroleptic haloperidol had the opposite effect in the first two models only, as expected. The S(+) isomers of NPA and 11-OH-NPa have shown behavioral evidence of antidopaminergic activity, especially in the limbic system. Unlike the neuroleptic, S(+)NPA did not show DA-synthesis enhancing actions in accumbens or striatal tissue but, instead, inhibited DA synthesis like its R(-) antipode in all three test paradigms. S(+)11-OH-NPa given alone produced minor changes in the HVA/DA ratio and did not antagonize R(-)11-OH-NPa, weakly increased accumulation of DOPA in the second model, and had no effect in the third--all without regional selectivity. In the test of autoreceptor functioning, the dihydroxyaporphine S(+)NPA, but not S(+)11-OH-NPa, inhibited DA synthesis and this effect, in turn, was largely reversed by haloperidol, as were the inhibitory effects of the three R(-)aporphines tested. In this model, however, neither S(+)NPA nor S(+)11-OH-NPa antagonized the DA-synthesis inhibiting effect of R(-)APO as haloperidol did. Overall, these results are consistent with evidence that R(-)NPA and 11-OH-NPa have high affinity at D-2 receptor sites in rat brain and show behavioral effects of typical DA agonists. The non-stereoselective inhibitory effects of NPA on DA synthesis may reflect its activity as a weak DA agonist with very low intrinsic activity, but may also include a direct "catechol-effect" on tyrosine hydroxylase. In contrast, R(-)11-OH-NPa appears to be a stereoselective D-2 agonist, active at autoreceptors as well as postsynaptic receptors, that lacks the nonstereospecific effects on DA metabolism of its catechol-aporphine congener. It may be a useful probe for the further characterization of dopamine receptors and autoreceptors.

Crystal and solution structures of d(CGC[e6G]AATTCGCG)-drug complexes reveal conformational polymorphism of O6-ethyl-guanine:cytosine base pair.

O6-ethyl-guanine (e6G) is a relatively persistent alkylation lesion caused by the exposure of DNA to carcinogen N-ethyl-N-nitrosourea. We have studied the structural consequences of the e6G incorporation in DNA by X-ray crystallography and NMR. We have obtained crystals of the modified DNA dodecamer d(CGC[e6G]AATTCGCG) complexed to several minor groove binding drugs including Hoechst 33258, Hoechst 33342, netropsin, and SN6999. The space group of the crystals from those complexes is P2(1)2(1)2(1). However the crystal structure of the SN6999 complex is not isomorphous to that from the other three complexes. In all four refined crystal structures the drugs bind in the narrow minor groove at or close to the central AATT region of the dodecamer B-DNA duplex. The DNA conformation is influenced by the binding of drugs. The eight independent e6G:C base pairs have a conformation ranging from one with three-centered hydrogen bonds between the bases to a wobble conformation with two hydrogen bonds. The ethyl group of the eight e6G bases is mostly in the proximal orientation to N7. Our 1D and 2D-NMR studies of the same (free) dodecamer reveal that the e6G:C base pairs in the duplex are likely to adopt a wobble conformation in solution. Those results suggest that the e6G:C base pair has a dynamic equilibrium among various conformations, which may present an ambiguous signal to cells. In contrast, the e6G:T base pair adopts a Watson-Crick-like conformation. This may be a plausible explanation of why thymine is found preferentially incorporated across the e6G during replication.

Crystal structures of four morpholino-doxorubicin anticancer drugs complexed with d(CGTACG) and d(CGATCG): implications in drug-DNA crosslink.

Among the new generations of anthracycline drugs, morpholino-doxorubicin (MDox) and its derivative have unusually potent activity when compared with the parent doxorubicin. 3"-Cyano-morpholino-doxorubicin (CN-MDox) has been suggested to form a covalent crosslink to DNA, although the exact mode of interactions remains unclear. To establish the structural basis of this crosslink, we carried out X-ray diffraction analyses of the complexes between four different morpholino-doxorubicins (i.e., MDox, CN-MDox, (R)- and (S)-2"-methoxy-morpholino-Dox (MMDox)) and two DNA hexamers CGTACG and CGATCG. Their crystal data are similar to other Dau/Dox complexes with space group P4(1)2(1)2,a = b approximately 28 A, c approximately 53 A. The refined structures at approximately 1.8 A resolution revealed that two drug molecules bind to the duplex with the aglycons intercalated between the CpG steps with their N3'-morpholino-daunosamines in the minor groove. The morpholino moiety is flexible and may adopt different conformations dependent on the sequence context. The O1" atoms of the two morpholino groups in the drug-DNA complexes are in van der Waals contact. The structural results suggest possible crosslinking mechanism of CN-MDox. It is worth pointing out that by linking two piperazinyl- or piperidinyl-doxorubicins at the 1" positions a new type of bis-doxorubicin derivatives may be synthesized which may bind to a hexanucleotide sequence with some specificity.

Molecular structure of antitumor drug steffimycin and modelling of its binding to DNA.

The molecular and crystal structure of steffimycin have been determined by single crystal X-ray diffraction to 0.9 angstrom resolution. The triclinic crystals are in the space group P1, with the unit cell dimensions of a = 8.606(3) angstrom, b = 22.168(7) angstrom, c = 8.448(2) angstrom, alpha = 97.56(3) degrees, beta = 95.97(2) degrees, gamma = 87.94(3) degrees, Z = 2. The structure was solved by direct methods and refined by the full-matrix least-squares method to a final R value of 0.065 with 3405 (Inet greater than 2.0 sigma (Inet] observed reflections using the NRCVAX software package. The crystal lattice includes 2 independent steffimycin, 3 water and one 2-methyl-2,4-pentanediol molecules. The conformation of steffimycin is grossly similar to other anthracycline antibiotics including daunorubicin. The crystal packing interactions of steffimycin suggest a preferred stacking of the aglycone chromophore of the antibiotic which resembles the intercalative interactions seen in the daunorubicin-d(CGTACG) (Wang et al., Biochemistry 26, 1152 (1987] and nogalamycin-d(CGT(pS)ACG) (Liaw et al., Biochemistry 28, 9913 (1989] complexes. The atomic coordinates data from these complexes were used to model the intercalative binding of steffimycin to DNA. The models were then stereochemically idealized by the constraint refinement program NUCLSQ. Subsequently XPLOR software package was used for energy minimization of these models in vacuo. The model building studies suggest that steffimycin has a higher CpG base sequence specificity over the TpA step, similar to that of daunorubicin and nogalamycin.