Tag: 原子力显微镜

Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation

Atomic Force Microscopy ( AFM ) can be utilized to determine the mechanical properties of tumor tissues in different kinds of cancers, for example breast cancer, liver cancer and lung cancer.

Oral squamous cell carcinoma (OSCC) is a common subtype of head and neck and other malignant tumors that occurs in increasing numbers. It is therefore important to learn more about the biological factors connected with the early diagnosis and treatment of OSCC. *

The human trophoblast cell surface antigen 2 (TROP2), which is also called tumor-associated calcium signal transduction-2 (TACSTD-2), is a surface glycoprotein encoded by TACSTD. *

Among the various biochemical mechanisms involved in tumorigenesis, the role of β-catenin has been studied extensively. This has shed light on the biological functions of TROP2 and its use as a prognostic biomarker for OSCC. *

TROP2 regulates tumorigenic properties including cancer cell adhesion, invasion, and migration and is overexpressed in many human cancers. Inhibiting TROP2 expression has shown promise in clinical applications. *

In the article “Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation” Baoping Zhang, Shuting Gao, Ruiping Li, Yiting Li, Rui Cao, Jingyang Cheng, Yumeng Guo, Errui Wang, Ying Huang and Kailiang Zhang investigate the role of TROP2 in OSCC patients using a combination of biophysical approaches including atomic force microscopy. *

The authors demonstrate the tissue morphology and mechanics of OSCC samples during tumor development using NanoWorld Pointprobe® CONTR AFM probes for the Atomic Force Microscopy described in the article and they believe that their findings will help develop TROP2 in accurately diagnosing OSCC in tumors with different grades of differentiation. *

Figure 5 from Baoping Zhang et al. “Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation”: Surface morphology of OSCC tissue sections via AFM detection, irregular morphology appeared in the low differentiation NanoWorld Pointprobe CONTR AFM probes were used for the Atomic Force Microscopy
Figure 5 from Baoping Zhang et al. “Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation”:
Surface morphology of OSCC tissue sections via AFM detection, irregular morphology appeared in the low differentiation

*Baoping Zhang, Shuting Gao, Ruiping Li, Yiting Li, Rui Cao, Jingyang Cheng, Yumeng Guo, Errui Wang, Ying Huang and Kailiang Zhang
Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation
BMC Cancer volume 20, Article number: 815 (2020)
DOI: https://doi.org/10.1186/s12885-020-07257-7

Please follow this external link to read the whole article: https://rdcu.be/cfC9G

Open Access : The article “Tissue mechanics and expression of TROP2 in oral squamous cell carcinoma with varying differentiation” by Baoping Zhang, Shuting Gao, Ruiping Li, Yiting Li, Rui Cao, Jingyang Cheng, Yumeng Guo, Errui Wang, Ying Huang and Kailiang Zhang is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.

Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation

Block copolymers, including multiblock copolymers of an amphiphilic nature, because of their ability to form various supramolecular structures are attracting a lot of research interest these days. The direct influence on the supramolecular organization of block copolymers is a way of controlling both the mechanical and physicochemical properties of polymer materials obtained on this basis. *

In the article “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation” Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova and Ilya V. Vorotyntsev describe how they investigated Multiblock copolymers obtained based on PPEG, D4 (octamethylcyclotetrasiloxane ) and TDI ( 2,4-toluene diisocyanate ).*

The authors studied the realized polymers as membrane materials for the separation of gas mixtures containing CO2/CH4 and CO2/N2 and went on to show that polymers with a cellular supramolecular structure exhibit lower permeability for CO2 in comparison with polymeric film materials whose supramolecular structure is constructed on the basis of the “core-shell” principle. *

It was shown in the above mentioned article that polymers are promising as silica-based membrane materials for the separation of gas mixtures containing CO2/CH4 and CO2/N2. *

As the polymer material investigated for this article is rather soft NanoWorld Pointprobe® FMR AFM probes with a typical force constant of around 2.8 N/m were used for the analysis by atomic force microscopy of the membrane surface.*

Figure 15 from Ilsiya M. Davletbaeva et al “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation”: AFM Images. (a): [PPEG]:[TDI] = 1:10; (b): [PPEG]:[D4]:[TDI] = 1:15:10; (c): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.2 wt.%, (d): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.4 wt.%. NanoWorld Pointprobe® FMR AFM probes were used.
Figure 15 from Ilsiya M. Davletbaeva et al “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation”:
AFM Images. (a): [PPEG]:[TDI] = 1:10; (b): [PPEG]:[D4]:[TDI] = 1:15:10; (c): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.2 wt.%, (d): [PPEG]:[D4]:[TDI] = 1:15:10 [ASiP] = 0.4 wt.%.

*Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova, and Ilya V. Vorotyntsev
Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation
Membranes 2021, 11(2), 94
DOI: https://doi.org/10.3390/membranes11020094

Please follow this external link to read the full article: https://www.mdpi.com/2077-0375/11/2/94/htm#

Open Access : The article “Amphiphilic Poly(dimethylsiloxane-ethylene-propylene oxide)-polyisocyanurate Cross-Linked Block Copolymers in a Membrane Gas Separation” by Ilsiya M. Davletbaeva, Ilgiz M. Dzhabbarov, Askhat M. Gumerov, Ilnaz I. Zaripov, Ruslan S. Davletbaev, Artem A. Atlaskin, Tatyana S. Sazanova, and Ilya V. Vorotyntsev is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.

Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure

N-cadherin is a transmembrane glycoprotein expressed by mesenchymal origin cells and is located at the adherens junctions. It regulates also cell motility and contributes to cell signaling.*

A pharmacological approach to inhibit N-cadherin expression or to block its function could be relevant to prevent disease progression and metastasis development.*

In the article “Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure” Céline Elie-Caille, Isabelle Lascombe, Adeline Péchery, Hugues Bittard and Sylvie Fauconnet, describe how they aimed at exploring the expression level of N-cadherin in invasive bladder cancer cells upon GW501516 exposure by both molecular biology techniques such as RTqPCR and Western blotting and atomic force microscopy (AFM) using an AFM tip functionalized with a monoclonal antibody directed against this adhesion molecule. *

The Atomic Force Microscope is a mighty nanoanalytical tool for studying biological samples under liquid, in pathological or physiological conditions, and at the scale of a single cell. It allows to characterize cells and their modification upon drug exposure or function alteration, in terms of cell surface topography or cell adhesion. *

The authors demonstrated for the first time, that the PPARβ/δ activator from a concentration of 15 µM decreased the full length N-cadherin at the mRNA and protein level and significantly reduced its cell surface coverage through the measurements of the interaction forces involving this adhesion molecule. *

Using atomic force microscopy the authors carried out a morphological and topographical analysis on bladder cancer cells of different histologic grade. *

AFM imaging was carried out in contact mode on fixed cells (with an applied force of 0.1 V), the QI mode was used for alive cell imaging, all in liquid. *

Force spectroscopy in force mapping was used for cadherin/anti-cadherin antibody measurement interactions and cadherin mapping on cells. *

NanoWorld Pyrex-Nitride PNP-TR triangular shaped silicon nitride cantilevers ( CB2 with a typical spring constant of 0.08 N/m ) were used.

For force mapping the AFM cantilevers were calibrated. The AFM probes, made of silicon nitride, were functionalized by 1% APTES (3-(Aminopropyl)triethoxysilane) in toluene during 2 h, washed extensively with toluene, and then with ethanol.
The second step consisted in an incubation in 0.2% glutaraldehyde solution during 10 min, followed by extensive washing with water. A naked AFM tip was used as a negative control.
The modified AFM tips were then incubated in 50 µg/mL primary antibody solution (N-cadherin GC-4 clone directed against the extracellular domain, N-cadherin 3B9 clone directed against the intracellular domain, E-cadherin HECD-1 clone directed against the extracellular domain) during 30 min, then washed with PBS 1X.
Finally, the functionalized AFM tip was saturated by incubation in 2 mg/mL RSA (rat serum albumin) solution during 30 min. *

Quantitative imaging AFM mode enabled to register more than hundred force spectroscopy curves per condition. The curves registered on cells were overlayed in order to highlight a specific pattern and the interaction peak areas were measured. *

Figure 1 from “Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure” by Céline Elie-Caille et al.: T24 and RT4 bladder cancer cell morphology and topography. a Images from control confluent cells by phase contrast microscopy. Scale bars: 200 µm. b, c AFM images obtained on control confluent cells, after glutaraldehyde fixation, in contact mode in liquid. b AFM height images. c AFM deflection images. Scale bars: 10 µm NanoWorld Pyrex-Nitride triangular PNP-TR silicon nitride AFM probes were used for the atomic force microscopy.
Figure 1 from “Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure” by Céline Elie-Caille et al.:
T24 and RT4 bladder cancer cell morphology and topography. a Images from control confluent cells by phase contrast microscopy. Scale bars: 200 µm. b, c AFM images obtained on control confluent cells, after glutaraldehyde fixation, in contact mode in liquid. b AFM height images. c AFM deflection images. Scale bars: 10 µm

* Céline Elie-Caille, Isabelle Lascombe, Adeline Péchery, Hugues Bittard amd Sylvie Fauconnet
Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure
Molecular and Cellular Biochemistry (2020) 471:113–127
DOI: https://doi.org/10.1007/s11010-020-03771-1

Please follow this external link to read the full article: https://link.springer.com/article/10.1007/s11010-020-03771-1

Open Access : The article “Molecular and nanoscale evaluation of N-cadherin expression in invasive bladder cancer cells under control conditions or GW501516 exposure” by Céline Elie-Caille, Isabelle Lascombe, Adeline Péchery, Hugues Bittard and Sylvie Fauconnet is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/.