MicroRNA-448 suppresses osteosarcoma cell proliferation and invasion through targeting EPHA7

<div><p>Osteosarcoma is the most common type of malignant bone tumor, often affecting adolescents and children. MicroRNAs (miRNAs) are a group of small, non-protein coding, endogenous RNAs that play critical roles in osteosarcoma tumorigenesis. In our study, we demonstrated that miR-448 expression was downregulated in osteosarcoma tissues and cell lines. Overexpression of miR-448 suppressed osteosarcoma cell proliferation, colony formation and migration. Moreover, we found that EPHA7 was a direct target gene of miR-448 in osteosarcoma cells. We further demonstrated that the EPHA7 expression level was upregulated in osteosarcoma tissues. Interestingly, the expression level of EPHA7 was inversely correlated with the expression level of miR-448 in osteosarcoma tissues. In addition, elevated expression of miR-448 suppressed osteosarcoma cell proliferation and invasion through targeting EPHA7. Taken together, these findings suggest that miR-448 functioned as a tumor suppressor gene in the development of osteosarcoma through targeting EPHA7.</p></div

Overexpression of miR-448 suppressed osteosarcoma cell proliferation, colony formation and migration.

<p>(A) The expression level of miR-448 in osteosarcoma cell lines (U2OS, MG-63, SAOS-2 and SOSP-9607) and the osteoblast cell line (hFOB) was determined by qRT-PCR. (B) miR-448 expression was significantly upregulated in the MG-63 cells after treatment with miR-448 mimic. (C) Elevated expression of miR-448 suppressed MG-63 cell proliferation. (D) Overexpression of miR-448 also decreased cyclin D1 expression in the MG-63 cells.(E) miR-448 expression was significantly upregulated in the U2OS cells after treatment with miR-448 mimic.(F) Elevated expression of miR-448 suppressed U2OS cell proliferation.(G) Overexpression of miR-448 inhibited MG-63 cell colony formation. The relative cell colony formation is shown. (H) Overexpression of miR-448 inhibited U2OS cell colony formation. The relative cell colony formation is shown. (I) Ectopic expression of miR-448 suppressed MG-63 cell migration. The relative open wound is shown. (J)Ectopic expression of miR-448 suppressed U2OS cell migration. The relative open wound is shown.*p<0.05, **p<0.01 and ***p<0.001.</p

miR-448 expression level was downregulated in osteosarcoma tissues.

<p>(A) The expression level of miR-448 in the osteosarcoma tissues and their related normal tissues was determined by qRT-PCR. (B) The expression level of miR-448 was lower in osteosarcoma tissues compared to that in the related normal tissues.</p

Elevated expression of miR-448 suppressedosteosarcoma cell proliferation and invasion by targeting EPHA7.

<p>(A) The expression level of EPHA7 in the osteosarcoma cell lines (U2OS, MG-63, SAOS-2 and SOSP-9607)and osteoblast cell line (hFOB) was measured by qRT-PCR. (B) The EPHA7 mRNA expression was significantly upregulated in the MG-63 cells after treatment with EPHA7 vector. (C) The protein expression of EPHA7 was determined by Western blot. (D) CCK8 assay results demonstrated that EPHA7 overexpression restored miR-448 overexpression MG-63 cell proliferation. (E) Overexpression of EPHA7 promoted cyclin D1 expression in the miR-448 overexpressing MG-63 cells. (F) Overexpression of EPHA7 promoted miR-448 overexpressing MG-63 cell migration. (G) The relative migrative wound was shown. *p<0.05.</p

Cl-Loss Dynamics of Vinyl Chloride Cations in the B²A″ State: Role of the C²A′ State

The dissociative photoionization of vinyl chloride (C₂H₃Cl) in the 11.0–14.2 eV photon energy range was investigated using threshold photoelectron photoion coincidence (TPEPICO) velocity map imaging. Three electronic states, namely, A²A′, B²A″, and C²A′, of the C₂H₃Cl⁺ cation were prepared, and their dissociation dynamics were investigated. A unique fragment ion, C₂H₃⁺, was observed within the excitation energy range. TPEPICO three-dimensional time-sliced velocity map images of C₂H₃⁺ provided the kinetic energy release distributions (KERD) and anisotropy parameters in dissociation of internal-energy-selected C₂H₃Cl⁺ cations. At 13.14 eV, the total KERD showed a bimodal distribution consisting of Boltzmann- and Gaussian-type components, indicating a competition between statistical and non-statistical dissociation mechanisms. An additional Gaussian-type component was found in the KERD at 13.65 eV, a center of which was located at a lower kinetic energy. The overall dissociative photoionization mechanisms of C₂H₃Cl⁺ in the B²A″ and C²A′ states are proposed based on time-dependent density functional theory calculations of the Cl-loss potential energy curves. Our results highlight the inconsistency of previous conclusions on the dissociation mechanism of C₂H₃Cl⁺