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2.
Int J Mol Sci ; 23(19)2022 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-36233293

RESUMEN

Thyroid cancer remains the most common endocrine malignancy worldwide, and its incidence has steadily increased over the past four years. Papillary Thyroid Cancer (PTC) is the most common differentiated thyroid cancer, accounting for 80-85% of all thyroid cancers. Mitochondrial proteins (MRPs) are an important part of the structural and functional integrity of the mitochondrial ribosomal complex. It has been reported that MRPL9 is highly expressed in liver cancer and promotes cell proliferation and migration, but it has not been reported in PTC. In the present study we found that MRPL9 was highly expressed in PTC tissues and cell lines, and lentivirus-mediated overexpression of MRPL9 promoted the proliferation and migration ability of PTC cells, whereas knockdown of MRPL9 had the opposite effect. The interaction between MRPL9 and GGCT (γ-glutamylcyclotransferase) was found by immunofluorescence and co-immunoprecipitation experiments (Co-IP). In addition, GGCT is highly expressed in PTC tissues and cell lines, and knockdown of GGCT/MRPL9 in vivo inhibited the growth of subcutaneous xenografts in nude mice and inhibited the formation of lung metastases. Mechanistically, we found that knockdown of GGCT/MRPL9 inhibited the MAPK/ERK signaling pathway. In conclusion, our study found that the interaction of GGCT and MRPL9 modulates the MAPK/ERK pathway, affecting the proliferation and migration of PTC cells. Therefore, GGCT/MRPL9 may serve as a potential biomarker for PTC monitoring and PTC treatment.


Asunto(s)
Sistema de Señalización de MAP Quinasas , Neoplasias de la Tiroides , gamma-Glutamilciclotransferasa , Animales , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Desnudos , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/patología , gamma-Glutamilciclotransferasa/genética
3.
J Transl Med ; 20(1): 426, 2022 09 23.
Artículo en Inglés | MEDLINE | ID: mdl-36138468

RESUMEN

BACKGROUND: Long non-coding RNAs (lncRNAs) are closely related to the occurrence and development of cancer. Abnormally expressed lncRNA can be used as a diagnostic marker for cancer. In this study, we aim to investigate the clinical significance of MIR99AHG expression in lung adenocarcinoma (LUAD), and its biological roles in LUAD progression. METHODS: The relative expression of MIR99AHG in LUAD tissues and cell lines was analyzed using public databases and RT-qPCR. The biological functions of MIR99AHG were investigated using a loss-of-function approach. The effect of MIR99AHG on lung fibrosis was assessed by scratch assay, invasion assay and lung fibrosis rat model. FISH, luciferase reporter assay and immunofluorescence were performed to elucidate the underlying molecular mechanisms. RESULTS: LncRNA MIR99AHG expression level was downregulated in LUAD tissues and cell lines. Low MIR99AHG levels were associated with poorer patient overall survival. Functional analysis showed that MIR99AHG is associated with the LUAD malignant phenotype in vitro and in vivo. Further mechanistic studies showed that, MIR99AHG functions as a competitive endogenous RNA (ceRNA) to antagonize miR-136-5p-mediated ubiquitin specific protease 4 (USP4) degradation, thereby unregulated the expression of angiotensin-converting enzyme 2 (ACE2), a downstream target gene of USP4, which in turn affected alveolar type II epithelial cell fibrosis and epithelial-mesenchymal transition (EMT). In summary, the MIR99AHG/miR-136-5p/USP4/ACE2 signalling axis regulates lung fibrosis and EMT, thus inhibiting LUAD progression. CONCLUSION: This study showed that downregulated MIR99AHG leads to the development of pulmonary fibrosis. Therefore, overexpression of MIR99AHG may provide a new approach to preventing LUAD progression.


Asunto(s)
Adenocarcinoma , Neoplasias Pulmonares , MicroARNs , Fibrosis Pulmonar , ARN Largo no Codificante , Adenocarcinoma/genética , Enzima Convertidora de Angiotensina 2 , Animales , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares/patología , MicroARNs/genética , MicroARNs/metabolismo , Fibrosis Pulmonar/genética , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ratas , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo
4.
Aging (Albany NY) ; 14(11): 4755-4768, 2022 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-35657638

RESUMEN

The endocrine therapy resistance of breast cancer is the difficulty and challenge to be urgently solved in the current treatment. In this study, we examined the effects of noncoding RNA LINC00094 and miR-19a-3p on breast cancer in vivo and in vitro by RT-QPCR, Western Blot, luciferase assay, immunofluorescence and drug sensitivity tests. The plasma level of CYP19A1 in patients with breast cancer resistance was lower than that in drug sensitive patients. Compared with normal subjects, miR-19a-3p was highly expressed in plasma of patients with breast cancer. miR-19a-3p is highly expressed in estrogen receptor positive breast cancer cells. The expression of miR-19a-3p promoted the migration and EMT of breast cancer cells and reduced the sensitivity of breast cancer to Letrozole. LINC00094 sponge adsorbed miR-19a-3p. LINC00094 promotes the expression of CYP19A1, the target gene of miR-19a-3p, and inhibits the EMT process of breast cancer, ultimately promoting the sensitivity of ER-positive breast cancer cells to Letrozole. This study found a new mechanism of Letrozole sensitivity in ER positive breast cancer.


Asunto(s)
Neoplasias de la Mama , MicroARNs , Aromatasa/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Letrozol , MicroARNs/genética , MicroARNs/metabolismo
5.
Opt Express ; 18(16): 17273-9, 2010 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-20721115

RESUMEN

Arbitrary connector for waveguides of different cross sections is proposed and designed theoretically based on the embedded optical transformation theory. First, the general expressions of constitutive tensors of the metamaterials filled in the connector are derived. Second, there are some full-wave simulations that validate the constitutive tensors derived. The results show that the connector with metamaterials inclusions with designed constitutive parameters can fulfill the reflectionless transmission of electromagnetic waves between waveguides of different cross sections. Finally, connectors of several forms are investigated parametrically, and two sets of constitutive tensors that can be physically achieved by existing metamaterials are gotten. It is believed that this study provides a feasible way to fulfill the efficient transmission of electromagnetic waves between waveguides of different cross sections.


Asunto(s)
Simulación por Computador , Luz , Refractometría/instrumentación , Dispersión de Radiación , Diseño de Equipo
6.
Opt Express ; 16(2): 1007-19, 2008 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-18542174

RESUMEN

The surface polariton properties of TM or TE plane wave scattered by a coated cylinder are investigated in this paper. The coated cylinder (whose outer radius is much smaller than the wavelength) is assumed to be electrically small and low dissipative. Analytical formulas of the plasmonic resonances are derived and found to agree well with those obtained from exact expressions in the classical scattering theory. The behaviors of the scattering coefficients at resonances are also discussed and compared for different cases. While a single cylinder has the resonance at the relative permittivity of epsilon(r) = -1 (or relative permeability of mu(r) = -1) for the TE (or TM) polarization, the resonances of the coated cylinders change with different n values (where n denotes the series term or mode of the field), and also the inner and outer radii. It is shown that the scattered field in the near zone can be enhanced significantly compared to the incident wave. For the TE incident case, we take a silver coated nano-cylinder as an example to illuminate the near-field optical effect. Also, we have studied the peak values of the nth order scattered field for different n values and electrical parameter k0b (where k0 is the wavenumber of the free space and b denotes the outer radius of the cylinder) around the cylinder. The derived new formulas for total cross sections are given and they may provide us with some potential photonic applications such as surface cleaning and etching.


Asunto(s)
Modelos Teóricos , Nanoestructuras , Refractometría/métodos , Resonancia por Plasmón de Superficie/métodos , Simulación por Computador , Luz , Dispersión de Radiación
7.
J Opt Soc Am A Opt Image Sci Vis ; 25(1): 55-63, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18157211

RESUMEN

The propagation of electromagnetic plane waves in an isotropic chiral medium is characterized, and a special interest is shown in chiral nihility and the effects of chirality on energy transmission. In particular, the wave impedance is matched to that of free space. Moreover, the refractive index n is also matched in impedance to that of free space when an appropriate value of the chirality is chosen. A "chiral nihility" medium is explored in which both the permittivity and the permeability tend to zero. Some specific case studies of chiral nihility are presented, and Brewster angles are found to cover an extremely wide range. The E-field distributions in these different cases where the chiral slab is placed in free space are analyzed by using the appropriate constitutive relations. It is shown from numerical calculations that one can obtain some critical characteristics of the effects of chirality on energy transmission and reflection, such as transparency and power tunneling.

8.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 2): 026609, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17358438

RESUMEN

Vector potential formulation and parametric studies of electromagnetic scattering problems of a sphere characterized by the rotationally symmetric anisotropy are studied. Both epsilon and mu tensors are considered herein, and four elementary parameters are utilized to specify the material properties in the structure. The field representations can be obtained in terms of two potentials, and both TE (TM) modes (with respect to r) inside (outside) the sphere can be derived and expressed in terms of a series of fractional-order (in a real or complex number) Ricatti-Bessel functions. The effects due to either electric anisotropy ratio (Ae=epsilont/epsilonr) or magnetic anisotropy ratio (Am=mut/mur) on the radar cross section (RCS) are considered, and the hybrid effects due to both Ae and Am are also examined extensively. It is found that the material anisotropy affects significantly the scattering behaviors of three-dimensional dielectric objects. For absorbing spheres, however, the Ae or Am no longer plays a significant role as in lossless dielectric spheres and the anisotropic dependence of RCS values is found to be predictable. The hybrid effects of Ae and Am are considered for absorbing spheres as well, but it is found that the RCS can be greatly reduced by controlling the material parameters. Details of the theoretical treatment and numerical results are presented.

9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 70(5 Pt 2): 056609, 2004 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15600781

RESUMEN

The field solution to the electromagnetic scattering of a plane wave by a uniaxial anisotropic sphere is obtained in terms of a spherical vector wave function expansion form. Using the source-free Maxwell's equations for uniaxial anisotropic media and making the Fourier transform of the field quantities, the electromagnetic fields in the spectral domain in uniaxial anisotropic media are assumed to have a form similar to the plane wave expanded also in terms of the spherical vector wave functions. Applying the continuous boundary conditions of electromagnetic fields on the surface between the air region and uniaxial anisotropic sphere, the coefficients of transmitted fields and the scattered fields in uniaxial anisotropic media can be obtained analytically in the expansion form of vector wave eigenfunctions. Numerical results for some special cases are obtained and compared with those of the classical Lorenz-Mie theory and the method of moments accelerated with the conjugate-gradient fast-Fourier-transform approach. We also present some new numerical results for the more general uniaxial dielectric material media.

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