Blocking VRK2 suppresses pulmonary adenocarcinoma progression via ERK1/2/AKT signal pathway by targeting miR-145-5p.

The article "Blocking VRK2 suppresses pulmonary adenocarcinoma progression via ERK1/2/AKT signal pathway by targeting miR-145-5p, by Y. Mu, W.-J. Liu, L.-Y. Bie, X.-Q. Mu, Y.-Q. Zhao, published in Eur Rev Med Pharmacol Sci 2021; 25 (1): 145-153-DOI: 10.26355/eurrev_202101_24378-PMID: 33506902" has been withdrawn from the authors since the design of the manuscript was not rigorous enough (there were some flaws in some experiments). The authors explain that they will perform further experiments. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/24378.

Blocking VRK2 suppresses pulmonary adenocarcinoma progression via ERK1/2/AKT signal pathway by targeting miR-145-5p.

OBJECTIVE: The incidence of pulmonary adenocarcinoma locates first in all the malignant tumors in the world. At present, there are many diagnostic methods for pulmonary adenocarcinoma, but there are a few methods that are mature or have ideal application prospects. We aim to explore the role of VRK2 in the occurrence and development of pulmonary adenocarcinoma and its possible regulatory mechanism. PATIENTS AND METHODS: Western blot and qRT-PCR were performed to assess the expression of VRK2. Flow cytometry, Western blot, and Caspase-3 colorimetric assay Kit were used to evaluate the apoptosis level. The proliferation, migration, and invasion ability were measured via cell cycle assay, wound healing, and transwell invasion assay. Luciferase assay verified the relationship between VRK2 and miR-145-5p. The effect of FGD5-AS1 on tumorigenesis of glioma was detected by the xenograft nude mice model. RESULTS: VRK2 was significantly increased in tumor tissues and cell lines. Loss of VRK2 promoted apoptosis level and inhibited the proliferation, migration, and invasion in A549 cells via regulating the ERK1/2/AKT signal pathway. Luciferase assay reported that VRK2 could bind with miR-145-5p. The level of miR-145-5p was negatively correlated with the expression of VRK2 and involved in VRK2 regulating tumor progression. The tumor growth assay showed that the silencing of VRK2 inhibited tumorigenesis with the inactivating ERK1/2/AKT pathway. CONCLUSIONS: Knockdown of VRK2 inhibited the development of pulmonary adenocarcinoma via regulating the ERK1/2/AKT signal pathway by targeting miR-145-5p, which providing some novel experimental basis for clinical treatment of pulmonary adenocarcinoma.

[Interpretation for the group standards in the handling of accidental leak coronavirus disease 2019 sample].

Biosafety is an important guarantee of the new coronavirus laboratory test. The accident treatment of sample overflow and sprinkle is a necessary part of the emergency plan for testing activities. Beijing Preventive Medicine Association coordinated biosafety experts of COVID-19 laboratories from Beijing CDC, to write up "The standard for handling of accidents of corona virus disease 2019 sample (T/BPMA 0005-2020)" . The group standard was based on the guidelines of China and WHO, and combined with the practical experience of COVID-19 epidemic and the principle of "scientific, normative, applicable and feasible" . Through all kinds of risk Assessment, it included the spillover of samples caused by the packing of COVID-19 (highly pathogenic) samples, the overflow and sprinkle in the laboratory during the detection operation, and the spillage accident occurred during the transfer of samples in the same building. The standard could guide and standardize the handling methods of accidental overflow and sprinkle that may occur in the SARS-CoV-2 testing laboratories in the city.

A novel NADH-dependent carbonyl reductase with unusual stereoselectivity for (R)-specific reduction from an (S)-1-phenyl-1,2-ethanediol-producing micro-organism: purification and characterization.

AIMS: To purify and characterize the (R)-specific carbonyl reductase from Candida parapsilosis; to compare the enzyme with other stereospecific oxidoreductases; and to develop an available procedure producing optically active (R)-1-phenyl-1,2-ethanediol (PED). METHODS AND RESULTS: An (R)-specific carbonyl reductase was found and purified from C. parapsilosis through four steps, including blue-sepharose affinity chromatography. The relative molecular mass of the enzyme was estimated to be 35 kDa on gel-filtration chromatography and 37.5 kDa on Sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The purified enzyme catalysed the reduction of various ketones, including alkyl and aromatic ketones, and was specific to short-chain and medium-chain alkyl ketones. The enzyme activity was inhibited by divalent ion of CuSO(4) and FeSO(4), whereas zincum ion stimulated its activity. For catalysing reduction, the enzyme performed maximum activity at pH 6.0 and the optimum temperature was 45 degrees C. The carbonyl reductase catalysed asymmetric reduction of beta-hydroxyacetophenone to the corresponding (R)-PED with the optical purity of 100% enantiomeric excess (e.e.). By analysing its partial amino acid sequences, the enzyme was proposed to be a novel stereospecific carbonyl reductase. CONCLUSIONS: The purified carbonyl reductase showed unusual stereospecificity and catalysed the NADH-dependent reduction of beta-hydroxyacetophenone to (R)-PED. The enzyme was different from other stereoselective oxidoreductases in catalytic properties. SIGNIFICANCE AND IMPACT OF THE STUDY: The discovery of (R)-specific oxidoreductase exhibiting unusual stereospecificity towards hydroxyl ketone is valuable for the synthesis of both enantiomers of useful chiral alcohols, and provides research basis for the achievement of profound knowledge on the relationship between structure and catalytic function of (R)-specific enzymes, which is meaningful for the alteration of stereospecificity by molecular methods to obtain the enzymes with desired stereospecificity.

X-ray diffraction by a one-dimensional paracrystal of limited size.

An explicit equation for X-ray diffraction by a finite one-dimensional paracrystal is derived. Based on this equation, the broadenings of reflections due to limited size and disorder are discussed. It depicts the paracrystalline diffraction over the whole reciprocal space, including the small-angle region where it degenerates into the Guinier equation for small-angle X-ray scattering. Positions of diffraction peaks by paracrystals are not periodic. Peaks shift to lower angles compared to those predicted by the average lattice constant. The shifts increase with increasing order of reflections and degree of disorder. If the heights and widths of the paracrystalline diffraction are treated as reduced quantities, they are functions of a single variable, N1/2 g. The width of the first diffraction depends mostly on size broadening for a natural paracrystal, where N1/2 g = 0.1-0.2. A method to measure the paracrystalline disorder and size using a single diffraction profile is proposed based on the equation of paracrystal diffraction. An initial value of size may be obtained using the Scherrer equation, that of the degree of disorder is then estimated by the alpha * law. Final values of the parameters are determined through least-squares refinement against observed profiles. An equation of diffraction by a polydisperse one-dimensional paracrystal system is presented for 'box' distribution of sizes. The width of the diffraction decreases with increasing breadth of the size distribution.

Analysis of the stability of hemoglobin S double strands.

The deoxyhemoglobin S (deoxy-HbS) double strand is the fundamental building block of both the crystals of deoxy-HbS and the physiologically relevant fibers present within sickle cells. To use the atomic-resolution detail of the hemoglobin-hemoglobin interaction known from the crystallography of HbS as a basis for understanding the interactions in the fibers, it is necessary to define precisely the relationship between the straight double strands in the crystal and the twisted, helical double strands in the fibers. The intermolecular contact conferring the stability of the double strand in both crystal and fiber is between the beta6 valine on one HbS molecule and residues near the EF corner of an adjacent molecule. Models for the helical double strands were constructed by a geometric transformation from crystal to fiber that preserves this critical interaction, minimizes distortion, and makes the transformation as smooth as possible. From these models, the energy of association was calculated over the range of all possible helical twists of the double strands and all possible distances of the double strands from the fiber axis. The calculated association energies reflect the fact that the axial interactions decrease as the distance between the double strand and the fiber axis increases, because of the increased length of the helical path taken by the double strand. The lateral interactions between HbS molecules in a double strand change relatively little between the crystal and possible helical double strands. If the twist of the fiber or the distance between the double strand and the fiber axis is too great, the lateral interaction is broken by intermolecular contacts in the region around the beta6 valine. Consequently, the geometry of the beta6 valine interaction and the residues surrounding it severely restricts the possible helical twist, radius, and handedness of helical aggregates constructed from the double strands. The limitations defined by this analysis establish the structural basis for the right-handed twist observed in HbS fibers and demonstrates that for a subunit twist of 8 degrees, the fiber diameter cannot be more than approximately 300 A, consistent with electron microscope observations. The energy of interaction among HbS molecules in a double strand is very slowly varying with helical pitch, explaining the variable pitch observed in HbS fibers. The analysis results in a model for the HbS double strand, for use in the analysis of interactions between double strands and for refinement of models of the HbS fibers against x-ray diffraction data.

X-ray diffraction from a helix of any length that displays cumulative azimuthal disorder.

An explicit formula has been derived to describe the attenuation and broadening of cylindrically averaged diffraction intensities from a helix of any given length which possesses cumulative azimuthal disorder. The application limits of an approximate formula, represented by the first term of this formula, are defined. Strategies to estimate the length of fibers, the degree of disorder, and the overlap of adjacent layer lines are outlined. Some features of diffraction patterns from the disordered helical structure of the HbS fiber are interpreted in light of these results. In these patterns, non-zero-order Bessel functions are attenuated and broadened due to azimuthal disorder and finite length. Adjacent layer lines overlap because of the very large axial repeat distance of the HbS fibers. As a result, the contribution of any Bessel function term with n > or = 10 is not discernible in these patterns. Only Bessel terms with n < 6 may be accurately estimated in these patterns, if instrumental broadening is negligible or correctable. The theory presented here may also be used to make a rough estimate of the degree of disorder in F-actin fibers by comparison of X-ray diffraction patterns with serial peak projections calculated assuming various degrees of disorder.

Computer models of a new deoxy-sickle cell hemoglobin fiber based on x-ray diffraction data.

A new x-ray fiber diffraction pattern from deoxygenated sickle cell erythrocytes has been observed. It displays 14 layer lines with a 109 A periodicity compared with the 64 A periodicity of the "classic" sickle cell hemoglobin (HbS) fiber. These data and association energy calculations serve as a basis for computer model building. Systematic searches over four-dimensional parameter space yielded twelve protofilament models that satisfy the following constraints: (a) two HbS molecules be related by twofold screw symmetry with a translational repeat of 109 A; (b) at least one of the substituted residues in HbS, val beta 6, should participate in intermolecular contacts; and (c) the energy of intermolecular interaction be less than -24 kcal/mol. Each of the protofilament models is a zigzag mono-strand that stands in contrast to the double-stranded protofilament of the "classic" fiber. Fiber models were constructed with each of the 12 protofilament models, pseudo-hexagonally packed. Searches of variable packing parameters showed four fiber models with minimal protofilament association energies and minimal differences between calculated transforms and observed data. The R-factor was less than 0.24 for each of these four models. In three of the fiber models the protofilament association energy is between -(93 and 130) kcal, and in a fourth, the energy is -64 kcal. One protofilament model constituted three distinct fiber models of the lower energy class, and a second protofilament model packed with a higher association energy into a fourth fiber model. The selection of a unique fiber model from among these four cannot be made because of the limited available data. Fibers models constructed with any of the ten other protofilament models do not satisfy the conditions of minimal association energy and R-factor.