The epithelial-mesenchymal transition (EMT) is critical for induction of invasiveness and metastasis of human cancers. In this study we investigated the expression profiles of the EMT markers, the relationship between EMT markers and patient/tumor/viral factors, and the interplay between major EMT regulators in human hepatocellular carcinoma (HCC). Reduced E-cadherin and nonmembranous ␤-catenin expression, the hallmarks of EMT, were shown in 60.2% and 51.5% of primary HCC samples, respectively. Overexpression of Snail, Twist, or Slug, the major regulators of EMT, was identified in 56.9%, 43.1%, and 51.4% of primary HCCs, respectively. Statistical analysis determined that Snail and Twist, but not Slug, are major EMT inducers in HCC: overexpression of Snail and/or Twist correlated with down-regulation of E-cadherin, nonmembranous expression of ␤-catenin, and a worse prognosis. In contrast, there were no such significant differences in samples that overexpressed Slug. Coexpression of Snail and Twist correlated with the worst prognosis of HCC. Hepatitis Cassociated HCC was significantly correlated with Twist overexpression. HCC cell lines with increased Snail and Twist expression (e.g., Mahlavu) exhibited a greater capacity for invasiveness/metastasis than cells with low endogenous Twist/Snail expression (e.g., Huh-7). Overexpression of Snail or/and Twist in Huh-7 induced EMT and invasiveness/metastasis, whereas knockdown of Twist or Snail in Mahlavu reversed EMT and inhibited invasiveness/metastasis. Twist and Snail were independently regulated, but exerted an additive inhibitory effect to suppress E-cadherin transcription. Conclusion: Our study provides a comprehensive profile of EMT markers in HCC, and the independent and collaborative effects of Snail and Twist on HCC metastasis were confirmed through different assays.

Serotonergic (5-HT) neurons in the brainstem modulate a wide range of physiological processes and behaviors. Two transcription factor genes, Pet-1 and Nkx2.2, are necessary but not sufficient to specify the 5-HT transmitter phenotype. Here we show that the Lim class homeobox gene Lmx1b is required for proper formation of the entire 5-HT system in the hindbrain, as indicated by the loss of expression of genes necessary for serotonin synthesis and transport in Lmx1b null mice. Lmx1b and Pet1 act downstream of Nkx2.2, and their expression is independently regulated at the time when 5-HT transmitter phenotype is specified. Ectopic expression of Lmx1b plus Pet-1 is able to induce formation of 5-HT cells in the most ventral spinal cord, where Nkx2.2 is normally expressed. Combined expression of all three genes, Lmx1b, Pet-1, and Nkx2.2, drives 5-HT differentiation in the dorsal spinal cord. Our studies therefore define a molecular pathway necessary and sufficient to specify the serotonergic neurotransmitter phenotype.

Mrg class G-protein-coupled receptors (GPCRs) are expressed exclusively in sensory neurons in the trigeminal and dorsal root ganglia. Pharmacological activation of Mrg proteins is capable of modulating sensory neuron activities and elicits nociceptive effects. In this study, we illustrate a control mechanism that allows the Runx1 runt domain transcription factor to generate compartmentalized expression of these sensory GPCRs. Expression of MrgA, MrgB, and MrgC subclasses is confined to an "A/B/C" neuronal compartment that expresses Runx1 transiently (or does not express Runx1), whereas MrgD expression is restricted to a "D" compartment with persistent Runx1 expression.

BaCKgRoUND aND aIMS: PreS mutants of HBV have been reported to be associated with HCC. We conducted a longitudinal study of the role of HBV preS mutations in the development of HCC, particularly in patients with chronic hepatitis B (CHB) having low HBV DNA or alanine aminotransferase (ALT) levels, and investigated the effects of secretion-defective preS2 deletion mutant (preS2ΔMT) on hepatocyte damage in vitro and liver fibrosis in vivo.appRoaCH aND ReSUltS: Association of preS mutations with HCC in 343 patients with CHB was evaluated by a retrospective case-control follow-up study. Effects of preS2ΔMT on HBsAg retention, endoplasmic reticulum (ER) stress, calcium accumulation, mitochondrial dysfunction, and liver fibrosis were examined. Multivariate analysis revealed a significant association of preS mutations with HCC (HR, 3.210; 95% CI, 1.072-9.613; P = 0.037) including cases with low HBV DNA or ALT levels (HR, 2.790; 95% CI, 1.133-6.873; P = 0.026). Antiviral therapy reduced HCC risk, including cases with preS mutations. PreS2ΔMT expression promoted HBsAg retention in the ER and unfolded protein response (UPR). Transmission electron microscopic examination, MitoTracker staining, real-time ATP assay, and calcium staining of preS2ΔMT-expressing cells revealed aberrant ER and mitochondrial ultrastructure, reduction of mitochondrial membrane potential and ATP production, and calcium overload. Serum HBV secretion levels were ~100fold lower in preS2ΔMT-infected humanized Fah-/-/ Rag2-/-/ Il2rg-/-triple knockout mice than in wild-type HBV-infected mice. PreS2ΔMT-infected mice displayed up-regulation of UPR and caspase-3 and enhanced liver fibrosis.

Lymphoid enhancer factor 1 (LEF1) activity is associated with progression of several types of cancers. The role of LEF1 in progression of hepatocellular carcinoma (HCC) remains poorly known. We investigated LEF1 expression in HCC and its interactions with epithelial‐mesenchymal transition (EMT) regulators (e.g., Snail, Slug, Twist) and stemness genes (e.g., octamer‐binding transcription factor 4 [Oct4], sex determining region Y‐box 2 [Sox2], Nanog homeobox [Nanog]). Microarray analysis was performed on resected tumor samples from patients with HCC with or without postoperative recurrence. LEF1 expression was associated with postoperative recurrence as validated by immunohistochemical staining in another HCC cohort. Among 74 patients, 44 displayed a relatively high percentage of LEF1 staining (>30% of HCC cells), which was associated with a reduced recurrence‐free interval (P < 0.001) and overall survival (P = 0.009). In multivariate analysis, a high percentage of LEF1 staining was significantly associated with low albumin level (P = 0.035), Twist overexpression (P = 0.018), Snail overexpression (P = 0.064), co‐expression of Twist and Snail (P = 0.054), and multinodular tumors (P = 0.025). Down‐regulation of LEF1 by short hairpin RNA decreased tumor sphere formation, soft agar colony formation, and transwell invasiveness of HCC cell lines Mahlavu and PLC. Xenotransplant and tail vein injection experiments revealed that LEF1 down‐regulation in Mahlavu reduced tumor size and metastasis. LEF1 up‐regulation in Huh7 increased sphere formation, soft agar colony formation, and transwell invasiveness. LEF1 was shown to physically interact with and transcriptionally activate promoter regions of Oct4, Snail, Slug, and Twist. Furthermore, Oct4, Snail, and Twist transactivated LEF1 to form a regulatory positive‐feedback loop. Conclusion: LEF1 plays a pivotal role in HCC progression through transcriptional regulation of Oct4 and EMT regulators.

MicroRNAs are small RNAs involved in various biological processes and cancer metastasis. miR-196a was associated with aggressive behaviors in several cancers. The role of miR-196a in hepatocellular carcinoma (HCC) metastasis remains unknown. This study aimed to examine the role of miR-196a in HCC progression. Expression of miR-196a was measured in 83 human HCC samples. The HCC patients with high miR-196a expression had younger ages, lower albumin levels, higher frequency with alpha-fetoprotein (AFP) levels ≥20 ng/mL, more macrovascular invasion, and non-early stages. Kaplan–Meier analysis showed that high miR-196a expression was associated with lower recurrence-free survival. Knockdown of miR-196a decreased transwell invasiveness, sphere formation, transendothelial invasion, and Slug, Twist, Oct4, and Sox2 expression, suppressed angiogenesis, and reduced sizes of xenotransplants and number of pulmonary metastasis. Down-regulation of miR-196a decreased Runx2 and osteopontin (OPN) levels. Knockdown of Runx2 in vitro resulted in comparable phenotypes with miR-196a down-regulation. Restoration of Runx2 in miR-196a-knockdown HCC reverted tumor phenotypes. This study showed that high expression of miR-196a is associated with HCC progression in a subset of younger patients. miR-196a mediates HCC progression via upregulation of Runx2, OPN, epithelial–mesenchymal transition (EMT) regulators, and stemness genes. We proposed that miR-196a can be used as a prognostic marker and a potential therapeutic target.

We demonstrate the development of a simply equipped displacement sensor utilizing spatially dispersive confocal technology. It feeds the amplified spontaneous emission (ASE) of a laser diode to a wavelength-selective feedback structure that corresponds to the position of a measured surface. The displacement sensor has a detecting range of 4 microm and precision of less than 2 nm, as proven by the analysis of the spectral shifts of the multipassed amplified output ASE. As compared with traditional sensors, the displacement sensor presented in our study requires fewer components and has as high precision as complex systems and a higher measurement rate due to the simpler strategy of displacement determination.

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