SOX2 suppresses CDKN1A to sustain growth of lung squamous cell carcinoma.

Since the SOX2 amplification was identified in lung squamous cell carcinoma (lung SCC), SOX2 transcriptional downstream targets have been actively investigated; however, such targets are often cell line specific. Here, in order to identify highly consensus SOX2 downstream genes in lung SCC cells, we used RNA-seq data from 178 lung SCC specimens (containing tumor and tumor-associated cells) and analyzed the correlation between SOX2 and previously-reported SOX2-controlled genes in lung SCC. In addition, we used another RNA-seq dataset from 105 non-small cell lung cancer cell lines (NSCLC; including 4 lung SCC cell lines) and again analyzed the correlation between SOX2 and the reported SOX2-controlled genes in the NSCLC cell lines (no tumor-associated cells). We combined the two analyses and identified genes commonly correlated with SOX2 in both datasets. Among the 99 genes reported as SOX2 downstream and/or correlated genes, we found 4 negatively-correlated (e.g., CDKN1A) and 11 positively-correlated genes with SOX2. We used biological studies to demonstrate that CDKN1A was suppressed by SOX2 in lung SCC cells. G1 cell cycle arrest induced by SOX2 siRNA was rescued by CDKN1A siRNA. These results indicate that the tumorigenic effect of SOX2 in lung SCC cells is mediated in part by suppression of CDKN1A

Observation of the Simultaneous Amplification of the Space Charge and the Fast Cyclotron Waves in a Spiral Beam-Plasma System

The amplification of the fast cyclotron wave is observed in a spiral beam-plasma system, overlapping on the amplifying space charge wave. The interferometer system output shows the amplifying wave pattern with an amplifying beat wave component or that overlapping on another amplifying one with a larger wavelength. The wave numbers and the amplification factors of both waves are determined from these wave patterns.departmental bulletin pape

The Effect of the Nonuniform Magnetic Field on the Instability of Plasma Wave

The amplification factor of the space charge wave of beam excited by the reactive medium instability decreases with the non-uniformity of the magnetic field increased. The anomalous damping of excited wave is observed near the point of local cyclotron resonance, which can be explained by the cyclotron damping of the longitudinal wave propagating obliquely to the field.departmental bulletin pape

Cyclotron Exitation of the Bernstein Wave in a Spiral Beam-Plasma System

departmental bulletin pape