Histone deacetylase 2 (HDAC2) is aberrantly regulated and plays a pivotal role in the development of hepatocellular carcinoma (HCC) through regulation of cell-cycle components at the transcriptional level, but the underlying mechanism leading to oncogenic HDAC2 remains unknown. In this study, we show that expression of CK2a (casein kinase II a subunit) was up-regulated in a large cohort of human HCC patients, and that high expression of CK2a was significantly associated with poor prognosis of HCC patients in terms of five-year overall survival. It was also found that CK2a over-expression positively correlated with HDAC2 over-expression in a subset of HCCs. We observed that treatment with epidermal growth factor (EGF) elicited an increase in CK2a expression and Akt phosphorylation, causing induction of HDAC2 expression in liver cancer cells. It was also observed that ectopic expression of dominant-negative CK2a blocked EGF-induced HDAC2 expression, and that ectopic CK2a expression attenuated the suppressive effect of Akt knockdown on HDAC2 expression in liver cancer cells. Targeted disruption of CK2a influenced the cell cycle, causing a significant increase in the number of liver cancer cells remaining in G 2 /M phase, and suppressed growth via repression of Cdc25c and cyclin B in liver cancer cells. Taken together, our findings suggest the oncogenic potential of CK2a in liver tumorigenesis. Furthermore, a regulatory mechanism for HDAC2 expression is proposed whereby EGF induces transcriptional activation of HDAC2 by CK2a/Akt activation in liver cancer cells. Therefore, this makes CK2a a promising target in cancer therapy.

We describe the DRILL (dry ion localization and locomotion) device, which is an interface for electrospray ionization (ESI)-mass spectrometry (MS) that exploits a swirling flow to enable the use of inertial separation to prescribe different fates for electrosprayed droplets based on their size. This source adds a new approach to charged droplet trajectory manipulation which, when combined with hydrodynamic drag forces and electric field forces, provides a rich range of possible DRILL operational modes. Here, we experimentally demonstrate sensitivity improvement obtained via vortex-induced inertial sorting of electrosprayed droplets/ions: one possible mode of DRILL operation. In this mode, DRILL removes larger droplets while accelerating the remainder of the ESI plume, producing a high velocity stream of gas-enriched spray with small, highly charged droplets and ions and directing it toward the MS inlet. The improved signal-to-noise ratio (10-fold enhancement) in the detection of angiotensin I is demonstrated using the DRILL interface coupled to ESI-MS along with an improved limit of detection (10-fold enhancement, 100 picomole) in the detection of angiotensin II. The utility of DRILL has also been demonstrated by liquid chromatography (LC)–MS: a stable isotope labeled peptide cocktail was spiked into a complex native tissue extract and quantified by unscheduled multiple reaction monitoring on a TSQ Vantage. DRILL demonstrated improved signal strength (up to a 700-fold) for 8 out of 9 peptides and had no effects on the peak shape of the transitions.

Several lines of evidence indicate that, together with deregulated growth, alteration of apoptosis plays a pivotal role in tumorigenesis. PUMA, a pro-apoptotic member of Bcl-2 family, mediates p53-dependent and -independent apoptosis. BAD is also a pro-apoptotic Bcl-2 family member and phosphorylation of BAD protein inhibits the pro-apoptosis function of BAD. To see whether the alteration of protein expressions of PUMA and phospho-BAD (p-BAD) are characteristics of human colorectal cancers, we analyzed the expression of these proteins in 103 colorectal carcinomas by immunohistochemistry. Also, we analyzed the mutation of the Bcl-2 homology 3 (BH3) domain of PUMA gene, an important domain in the apoptosis function of PUMA, by single-strand conformation polymorphism (SSCP) in 98 colorectal carcinomas. p-BAD immunostaining was detected in 62 cases (60.1%) of the 103 carcinomas, whereas it was not detected in the normal colonic mucosal epithelial cells. PUMA protein expression was detected in both cancer cells and normal mucosal cells in all of the 103 cases. However, the cancer cells showed higher intensities of PUMA immunostaining than the normal cells of the same patients in 50.4% of the cases. There was no association of the p-BAD expression with the PUMA expression. The mutational analysis revealed no PUMA BH3 domain mutation in the cancers. Our data indicated that expressions of both PUMA and p-BAD were increased in the colorectal cancer cells, and suggested that the increased expression of these proteins in malignant colorectal epithelial cells compared to the normal mucosal epithelial cells may possibly alter the cell death regulation during colorectal tumorigenesis.

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Intestinal metaplasia in gastric mucosa is considered a preneoplastic lesion that progresses to gastric cancer. However, the molecular networks underlying this lesion formation are largely unknown. NKX6.3 is known to be an important regulator in gastric mucosal epithelial differentiation. In this study, we characterized the effects of NKX6.3 that may contribute to gastric intestinal metaplasia. NKX6.3 expression was significantly reduced in gastric mucosae with intestinal metaplasia. The mRNA expression levels of both NKX6.3 and CDX2 predicted the intestinal metaplasia risk, with an area under the receiver operating characteristic curve value of 0.9414 and 0.9971, respectively. Notably, the NKX6.3 expression level was positively and inversely correlated with SOX2 and CDX2, respectively. In stable AGS NKX6.3 and MKN1 NKX6.3 cells, NKX6.3 regulated the expression of CDX2 and SOX2 by directly binding to the promoter regions of both genes. Nuclear NKX6.3 expression was detected only in gastric epithelial cells without intestinal metaplasia. Furthermore, NKX6.3-induced TWSG1 bound to BMP4 and inhibited BMP4-binding activity to BMPR-II. These data suggest that NKX6.3 might function as a master regulator of gastric differentiation by affecting SOX2 and CDX2 expression and the NKX6. Gastric cancer is still one of the malignancies with high incidence and mortality rates worldwide. 1 The stages of the precancerous cascade for gastric adenocarcinoma are a series of histologically recognizable changes in the gastric mucosa that follow a specific sequence: non-atrophic gastritis, multifocal atrophic gastritis, intestinal metaplasia, and dysplasia. 2-4 Of these, intestinal metaplasia is the replacement of gastric epithelium by epithelium displaying an intestinal phenotype with the appearance of goblet, Paneth, and absorptive cells. It is well known that Helicobacter pylori infection, high salt intake, smoking, and alcohol consumption are risk factors for gastric intestinal metaplasia. [5][6][7][8] Interestingly, altered expression of Muc5ac with the aberrant expression of Muc2 and caudal-related homologue 2 (CDX2) was detected in intestinal metaplasia of the stomach, which is characterized by the appearance of goblet cells and is considered to be a preneoplastic stage of gastric carcinogenesis. [9][10][11][12] Patients with gastric intestinal metaplasia showed a six-fold increased risk of gastric cancer than did those without gastric intestinal metaplasia. 13 Although much is known about the morphology and physiology of gastric intestinal metaplasia, the regulatory mechanisms that govern their intestinal differentiation still remain unclear.It was recently reported that NKX6.3, a third member of the NKX6 subfamily of NKX genes, is a novel transcription factor required for gastric epithelial differentiation. 14 In mouse embryos, NKX6.3 expression is restricted to endoderm-derived cells in the gastric antrum, pylorus, and proximal duodenum. 15 As a stratified squamous epithelium extends from the esophagus to the fundus of the m...