Publications by authors named "Qiyan Tan"

8 Publications

  • Page 1 of 1

Circular RNA Facilitates The Growth and Metastasis of Non-Small Cell Lung Cancer by Sponging .

Cell J 2021 Oct 30;23(5):552-561. Epub 2021 Oct 30.

Department of Laboratory, Hainan People's Hospital, Haikou, Hainan, China. Email:

Objective: There is growing evidence showing that circular RNAs (circRNAs) are crucial regulators in modulating the biological behavior of tumors. This work is aimed to probe the role of in non-small cell lung cancer (NSCLC) and to elucidate its mechanism of action.

Materials And Methods: In this experimental study, the differentially expressed circRNAs in NSCLC were screened using the GEO database (GSE158695). , and expression levels were determined by quantitative real-time polymerase chain reaction (qRT-PCR) analysis and Western blot. The proliferation, apoptosis, migration, and invasion of NSCLC cells were detected by CCK-8, flow cytometry, and transwell assays. RNA immunoprecipitation (RIP), RNA pull-down, and dual-luciferase reporter gene assays were performed to clarify the association between the and .

Results: was shown to be up-regulated in NSCLC tissues and cell lines. The up-regulation of is closely associated with advanced clinical stage of cancer, lymph node metastasis, and poor prognosis in NSCLC patients. knockdown impeded the proliferation, migration, and invasion of NSCLC cells and enhanced their apoptosis. Mechanistically, was demonstrated to up-regulate MMP2 expression via decoying and to facilitate the malignant biological behaviors of NSCLC cells.

Conclusion: This work reveals that is implicated in NSCLC cell growth and metastasis through the modulation of miR-326/miR-330-5p/MMP2, providing novel insights into the role of circRNAs in NSCLC progression.
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http://dx.doi.org/10.22074/cellj.2021.7913DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8588814PMC
October 2021

Diminishing Cohesion of Chitosan Films in Acidic Solution by Multivalent Metal Cations.

Langmuir 2020 05 29;36(18):4964-4974. Epub 2020 Apr 29.

Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, and School of Mechanical Engineering, Southeast University, Nanjing 211189, China.

Chitosan is a natural polymer with good biocompatibility, biodegradability, and bioactivity that has great potential for biomedical and industrial applications. Like other natural sugar-based polymers, chitosan molecules own versatile adhesion abilities to bind with various surfaces, owing to multiple functional moieties contained in the chain. To develop the promising biomaterials based on the chitosan chemistry, it is fundamentally important to figure out its adhesion mechanism under a certain condition, which leaves us numbers of open questions. In this work, we characterized the chitosan films adsorbed on a mica substrate in acidic solution and investigated the effects of multivalent salts on the cohesive behaviors of the films by means of the surface forces apparatus. The results showed that the cohesion capacities of chitosan films were reduced to around 30% of their original states after the addition of 10 M LaCl into 150 mM acetic acid, which could be partially recovered by holding the films at the contact position for a longer time. Surprisingly, the cohesion loss in the films exhibited the dependence on the properties of the metal cations including valance and concentration. The topography of the chitosan-coated surface also showed obvious aggregation in the presence of submicromolar of the salts. Here, we attributed these phenomena regarding cohesion loss to the mechanisms involved in the absorption of metal cations by the chitosan chains, which not only consumed the binding sites but also induced conformation change in the polymer network. Our findings may offer a suggestion for the production of chitosan-based materials to notice the potential impacts of ultralow concentrated salts that are usually neglected even under acidic conditions.
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http://dx.doi.org/10.1021/acs.langmuir.0c00438DOI Listing
May 2020

Development and parameter identification of a visco-hyperelastic model for the periodontal ligament.

J Mech Behav Biomed Mater 2017 04 31;68:210-215. Epub 2017 Jan 31.

Department of Stomatology, Nanjing Medical University, 210029 Nanjing, PR China.

The present study developed and implemented a new visco-hyperelastic model that is capable of predicting the time-dependent biomechanical behavior of the periodontal ligament. The constitutive model has been implemented into the finite element package ABAQUS by means of a user-defined material subroutine (UMAT). The stress response is decomposed into two constitutive parts in parallel which are a hyperelastic and a time-dependent viscoelastic stress response. In order to identify the model parameters, the indentation equation based on V-W hyperelastic model and the indentation creep model are developed. Then the parameters are determined by fitting them to the corresponding nanoindentation experimental data of the PDL. The nanoindentation experiment was simulated by finite element analysis to validate the visco-hyperelastic model. The simulated results are in good agreement with the experimental data, which demonstrates that the visco-hyperelastic model developed is able to accurately predict the time-dependent mechanical behavior of the PDL.
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http://dx.doi.org/10.1016/j.jmbbm.2017.01.035DOI Listing
April 2017

Structure and properties of water film adsorbed on mica surfaces.

J Chem Phys 2015 Sep;143(10):104705

Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University, Nanjing 211189, China.

The structure profiles and physical properties of the adsorbed water film on a mica surface under conditions with different degrees of relative humidity are investigated by a surface force apparatus. The first layer of the adsorbed water film shows ice-like properties, including a lattice constant similar with ice crystal, a high bearing capacity that can support normal pressure as high as 4 MPa, a creep behavior under the action of even a small normal load, and a character of hydrogen bond. Adjacent to the first layer of the adsorbed water film, the water molecules in the outer layer are liquid-like that can flow freely under the action of external loads. Experimental results demonstrate that the adsorbed water layer makes the mica surface change from hydrophilic to weak hydrophobic. The weak hydrophobic surface may induce the latter adsorbed water molecules to form water islands on a mica sheet.
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http://dx.doi.org/10.1063/1.4930274DOI Listing
September 2015

Study of DNA adsorption on mica surfaces using a surface force apparatus.

Sci Rep 2015 Feb 13;5:8442. Epub 2015 Feb 13.

Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, and School of Mechanical Engineering, Southeast University, Nanjing 211189, China.

We report our studies on the adsorption properties of double-stranded DNA molecules on mica surfaces in a confined environment using a surface force apparatus. Specifically, we studied the influence of cation species and concentrations on DNA adsorption properties. Our results indicated that divalent cations (Mg(2+) and Co(2+)) preferred to form uniform and moderately dense DNA layers on a mica substrate. By measuring the interactions between DNA-coated mica and bare mica in an aqueous solution, obvious adhesion was observed in a cobalt chloride solution, possibly due to the ion-correlation attraction between negatively charged DNA and the mica surface. Furthermore, the interaction differences that were observed with MgCl2 and CoCl2 solutions reveal that the specific adsorption behaviors of DNA molecules on a mica substrate were mediated by these two salts. Our results are helpful to elucidate the dynamics of DNA binding on a solid substrate.
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http://dx.doi.org/10.1038/srep08442DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4326959PMC
February 2015

Experimental observation of the ion-ion correlation effects on charge inversion and strong adhesion between mica surfaces in aqueous electrolyte solutions.

Langmuir 2014 Sep 29;30(36):10845-54. Epub 2014 Aug 29.

School of Mechanical Engineering and Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, Southeast University , Nanjing 211189, People's Republic of China.

Direct force measurements between two mica surfaces in aqueous electrolyte solutions over broad ranges of LaCl3 concentrations and pH values were carried out with a surface forces apparatus. Charge inversion on mica surfaces is detected once the LaCl3 concentration reaches a critical value. With the continual increase of LaCl3 concentrations, the mica surface will be overscreened by the counterions. It is demonstrated that the two mica surfaces may experience the jump-in contact even at high LaCl3 concentrations, which is seldom seen in monovalent salt solutions. The strong adhesion cannot be attributed to the van der Waals force alone, but should include the ion-ion correlation forces. Through adjusting the pH values in LaCl3 solutions, the ion-ion correlation force can be evaluated quantitatively. These results provide important insight into the fundamental understanding in the role of ion-ion correlations in ion screening mechanism and interactions between charged objects.
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http://dx.doi.org/10.1021/la5024357DOI Listing
September 2014

A study of structure and properties of molecularly thin methanol film using the modified surface forces apparatus.

Microsc Res Tech 2014 Nov 19;77(11):851-6. Epub 2014 Aug 19.

School of Mechanical Engineering, Southeast University, Nanjing, 211189, China.

A novel approach for studying the adsorption and evaporation processes of molecularly thin methanol film by the modified surface forces apparatus (M-SFA) is reported. This method can be used precisely to measure the thickness, morphology, and mechanical properties of the film confined between two mica surfaces in a real-time manner at gas atmosphere. By observing the adsorption and evaporation processes of the methanol molecule, it is found that the first adsorbed layer of the methanol film on the mica surface behaves as a solid-like structure. The thickness of this layer is measured to be about 3.2 Å, approximately equal to the diameter of a methanol molecule. Besides, this first adsorbed layer can carry normalized loads of more than 5.6 atm due to the carrying capacity conserved by the bond of mica-OH. The outer layers of the methanol film are further adsorbed with the increase of the exposure time, which are liquid-like and can be easily eliminated out from the substrate. The present study suggests that the interacting mode between hydroxy and mica is of great potential in material science and biomedical systems.
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http://dx.doi.org/10.1002/jemt.22425DOI Listing
November 2014

Imaging the condensation and evaporation of molecularly thin ethanol films with surface forces apparatus.

Rev Sci Instrum 2014 Jan;85(1):013702

Jiangsu Key Laboratory for Design and Manufacture of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189, China.

A new method for imaging condensation and evaporation of molecularly thin ethanol films is reported. It is found that the first adsorbed layer of ethanol film on mica surface behaves as solid like structure that cannot flow freely. With the increase of exposure time, more ethanol molecules condense over the mica surface in the saturated ethanol vapor condition. The first layer of adsorbed ethanol film is about 3.8 Å thick measured from the surface forces apparatus, which is believed to be the average diameter of ethanol molecules while they are confined in between two atomically smooth mica surfaces.
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http://dx.doi.org/10.1063/1.4860653DOI Listing
January 2014
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