MiR-1254 inhibits proliferation, migration and invasion of human brain tumour cell lines

Purpose: To investigate the expression of miR-1254 in 5 astrocytoma cell lines, and the mechanism involved.Methods: Total RNA was isolated by RNeasy RNA isolation kit while cDNA was prepared by RevertAid cDNA synthesis kit. The transcripts were analysed by real-time polymerase chain reaction (RT-PCR). Transfection of miR-1254 was carried out using FuGENE HD (Promega). Apoptosis was determined by DAPI, acridine orange (AO)/ethidium bromide (EB) and annexin V/PI double staining. Cell migration and invasion were investigated by wound healing and Martigel invasion assays, respectively. Protein expression was measured by western blotting.Results: Expression of miR-1254 was significantly down-regulated in the astrocytoma cell lines when compared to normal astrocyte cells (p < 0.05). Ectopic expression of miR-1254 in astrocytoma SW 1088 cells inhibited cell proliferation via initiation of apoptosis and cell cycle arrest. Over-expression of miR- 1254 also led to significant decrease in cell migration and invasion of SW 1088 astrocytoma cells (p < 0.05).Conclusion: The results show that the expression of miR-1254 is down-regulated in astrocytoma cell lines, but over-expression of miR-1254 inhibits proliferation of the cell lines via cell cycle arrest and apoptosis. Thus, miR-1254 has promising potential for use in the treatment of brain tumour.Keywords: Brain tumour, Astrocytoma, miR-1254, Apoptosis, Cell migratio

The heavy quarkonium inclusive decays using the principle of maximum conformality

The next-to-next-to-leading order (NNLO) pQCD correction to the inclusive decays of the heavy quarkonium $\eta_Q$ ($Q$ being $c$ or $b$) has been done in the literature within the framework of nonrelativistic QCD. One may observe that the NNLO decay width still has large conventional renormalization scale dependence due to its weaker pQCD convergence, e.g. about $(^{+4\%}_{-34\%})$ for $\eta_c$ and $(^{+0.0}_{-9\%})$ for $\eta_b$, by varying the scale within the range of $[m_Q, 4m_Q]$. The principle of maximum conformality (PMC) provides a systematic way to fix the $\alpha_s$-running behavior of the process, which satisfies the requirements of renormalization group invariance and eliminates the conventional renormalization scheme and scale ambiguities. Using the PMC single-scale method, we show that the resultant PMC conformal series is renormalization scale independent, and the precision of the $\eta_Q$ inclusive decay width can be greatly improved. Taking the relativistic correction $\mathcal{O}(\alpha_{s}v^2)$ into consideration, the ratios of the $\eta_{Q}$ decays to light hadrons or $\gamma\gamma$ are: $R^{\rm NNLO}_{\eta_c}|_{\rm{PMC}}=(3.93^{+0.26}_{-0.24})\times10^3$ and $R^{\rm NNLO}_{\eta_b}|_{\rm{PMC}}=(22.85^{+0.90}_{-0.87})\times10^3$, respectively. Here the errors are for $\Delta\alpha_s(M_Z) = \pm0.0011$. As a step forward, by applying the Pad$\acute{e}$ approximation approach (PAA) over the PMC conformal series, we obtain approximate NNNLO predictions for those two ratios, e.g. $R^{\rm NNNLO}_{\eta_c}|_{\rm{PAA+PMC}} =(5.66^{+0.65}_{-0.55})\times10^3$ and $R^{\rm NNNLO}_{\eta_b}|_{\rm{PAA+PMC}}=(26.02^{+1.24}_{-1.17})\times10^3$. The $R^{\rm NNNLO}_{\eta_c}|_{\rm{PAA+PMC}}$ ratio agrees with the latest PDG value $R_{\eta_c}^{\rm{exp}}=(5.3_{-1.4}^{+2.4})\times10^3$, indicating the necessity of a strict calculation of NNNLO terms.Comment: 10 pages, 4 figure