Gab2 mediates hepatocellular carcinogenesis by integrating multiple signaling pathways.

Our previous studies have found that Growth factor receptor-bound protein 2-associated binding protein 2 (Gab2)-a docking protein-governs the development of fatty liver disease. Here, we further demonstrate that Gab2 mediates hepatocarcinogenesis. Compared with a faint expression in para-carcinoma tissue, Gab2 was highly expressed in ∼60-70% of human hepatocellular carcinoma (HCC) specimens. Deletion of Gab2 dramatically suppressed diethylnitrosamine-induced HCC in mice. The oncogenic effects of Gab2 in HepG2 cells were promoted by Gab2 overexpression but were rescued by Gab2 knockdown. Furthermore, Gab2 knockout in HepG2 cells restrained cell proliferation, migration and tumor growth in nude mice. Signaling pathway analysis with protein kinase inhibitors demonstrated that oncogenic regulation by Gab2 in hepatic cells involved multiple signaling molecules, including ERK, Akt, and Janus kinases (Jaks), especially those that mediate inflammatory signaling. IL-6 signaling was increased by Gab2 overexpression and impaired by Gab2 deletion via regulation of Jak2 and signal transducer and activator of transcription 3 phosphorylation and the expression of downstream genes, such as Bcl-2 (B-cell lymphoma 2), c-Myc, MMP7 (matrix metalloproteinase-7), and cyclin D1in vitro and in vivo These data indicate that Gab2 mediates the pathologic progression of HCC by integrating multiple signaling pathways and suggest that Gab2 might be a powerful therapeutic target for HCC.-Cheng, J., Zhong, Y., Chen, S., Sun, Y., Huang, L., Kang, Y., Chen, B., Chen, G., Wang, F., Tian, Y., Liu, W., Feng, G.-S., Lu, Z. Gab2 mediates hepatocellular carcinogenesis by integrating multiple signaling pathways.

Microfluidic bioassay to characterize parasitic nematode phenotype and anthelmintic resistance.

With increasing resistance to anti-parasitic drugs, it has become more important to detect and recognize phenotypes of resistant isolates. Molecular methods of detecting resistant isolates are limited at present. Here, we introduce a microfluidic bioassay to measure phenotype using parameters of nematode locomotion. We illustrate the technique on larvae of an animal parasite Oesophagostomum dentatum. Parameters of sinusoidal motion such as propagation velocity, wavelength, wave amplitude, and oscillation frequency depended on the levamisole-sensitivity of the isolate of parasitic nematode. The levamisole-sensitive isolate (SENS) had a mean wave amplitude of 135 µm, which was larger than 123 µm of the levamisole-resistant isolate (LEVR). SENS had a mean wavelength of 373 µm, which was less than 393 µm of LEVR. The mean propagation velocity of SENS, 149 µm s-1, was similar to LEVR, 143 µm s-1. The propagation velocity of the isolates was inhibited by levamisole in a concentration-dependent manner above 0.5 µm. The EC50 for SENS was 3 µm and the EC50 for LEVR was 10 µm. This microfluidic technology advances present-day nematode migration assays and provides a better quantification and increased drug sensitivity. It is anticipated that the bioassay will facilitate study of resistance to other anthelmintic drugs that affect locomotion.

Studying the Role and Molecular Mechanisms of MAP4K3 in Sorafenib Resistance of Hepatocellular Carcinoma.

Sorafenib is the first FDA-approved therapeutic drug for molecular target medication on advanced-stage hepatocellular carcinoma. It is reported that sorafenib could improve the survival of progression-free patients for 4 to 6 months; however, most of the patients developed drug resistance. Thus, it is critical to reveal the biological mechanisms behind sorafenib resistance. In this study, a sorafenib-resistant model was developed by exposing HepG2 cells to sorafenib with gradient increasing concentration, and the resistance-related genes were screened by microarray. Real-time qPCR was used to validate selected gene expression of the resistance model, and lentivirus vector-mediated RNA interference was applied for specific gene knockdown. In addition, high-throughput High Celigo Select (HCS) and flow cytometry were used to measure the effect on cellular proliferation and apoptosis. As a result, our study established a sorafenib-resistant model with IC50 of 9.988 µM. The Affymetrix expression profile of the sorafenib-resistant model showed 35 resistant-related genes, and 91.4% of the resistant genes showed upregulation in HepG2 resistance cells. In addition, 20 genes were knocked down to measure cell proliferation, and MAP4K3 with high proliferation inhibiting phenotype was chosen for further study. Meanwhile, the HCS results revealed that shMAP4K3 transfection could downregulate resistant cell proliferation, and the flow cytometry results showed that cell apoptosis was significantly increased in the MAP4K3 knockdown group. In summary, MAP4K3 is a novel molecular marker for improving the drug sensitivity of sorafenib treatment in hepatocellular carcinoma.

Magnesium-dependent Phosphatase (MDP) 1 is a Potential Suppressor of Gastric Cancer.

BACKGROUND: Recurrence is the leading cause of treatment failure and death in patients with gastric cancer (GC). However, the mechanism underlying GC recurrence remains unclear, and prognostic markers are still lacking. METHODS: We analyzed DNA methylation profiles in gastric cancer cases with shorter survival (<1 year) or longer survival (> 3 years), and identified candidate genes associated with GC recurrence. Then, the biological effects of these genes on gastric cancer were studied. RESULTS: A novel gene, magnesium-dependent phosphatase 1 (mdp1), was identified as a candidate gene whose DNA methylation was higher in GC samples from patients with shorter survival and lower in patients with longer survival. MDP1 protein was highly expressed in GC tissues with longer survival time, and also had a tendency to be expressed in highly differentiated GC samples. Forced expression of MDP1 in GC cell line BGC-823 inhibited cell proliferation, whereas the knockdown of MDP1 protein promoted cell growth. Overexpression of MDP1 in BGC-823 cells also enhanced cell senescence and apoptosis. Cytoplasmic kinase protein c-Jun N-terminal kinase (JNK) and signal transducer and activator of transcription 3 (Stat3) were found to mediate the biological function of MDP1. CONCLUSION: These results suggest that MDP1 protein suppresses the survival of gastric cancer cells and loss of MDP expression may benefit the recurrence of gastric cancer.

Clinicopathologic features of 112 cases with mantle cell lymphoma.

OBJECTIVE: This study aims to explore the clinicopathologic features of 112 patients with mantle cell lymphoma (MCL). METHODS: Data from 112 MCL cases were collected, and immunohistochemical assay was conducted. Fluorescence in situ hybridization (FISH) detected a break in the CCND1 gene. The t-test was used in the statistical analysis. RESULTS: All tumor cells in the 112 cases expressed B cell-related antigen, including 1 blastoid subtype and 1 polymorphic subtype. Among all cases, 106 expressed CD5 and 104 expressed cyclin D1. A break in the CCND1 gene was not found in 3 cases with CD5-MCL. IgH/CCND1 polyploid was observed in 2 classic cases. CONCLUSION: MCL is a type of special immunophenotypic B-cell lymphoma. The prognoses of blastoid and polymorphic subtypes are poor. Special subtypes should be classified during diagnosis.

Tyrosine phosphatase Shp2 mediates the estrogen biological action in breast cancer via interaction with the estrogen extranuclear receptor.

The extranuclear estrogen receptor pathway opens up novel perspectives in many physiological and pathological processes, especially in breast carcinogenesis. However, its function and mechanisms are not fully understood. Herein we present data identifying Shp2, a SH2-containing tyrosine phosphatase, as a critical component of extranuclear ER pathway in breast cancer. The research checked that the effect of Shp2 on the tumor formation and growth in animal model and investigated the regulation of Shp2 on the bio-effect and signaling transduction of estrogen in breast cancer cell lines. The results showed that Shp2 was highly expressed in more than 60% of total 151 breast cancer cases. The inhibition of Shp2 activity by PHPS1 (a Shp2 inhibitor) delayed the development of dimethylbenz(a)anthracene (DMBA)-induced tumors in the rat mammary gland and also blocked tumor formation in MMTV-pyvt transgenic mice. Estradiol (E2) stimulated protein expression and phosphorylation of Shp2, and induced Shp2 binding to ERα and IGF-1R around the membrane to facilitate the phosphorylation of Erk and Akt in breast cancer cells MCF7. Shp2 was also involved in several biological effects of the extranuclear ER-initiated pathway in breast cancer cells. Specific inhibitors (phps1, phps4 and NSC87877) or small interference RNAs (siRNA) of Shp2 remarkably suppressed E2-induced gene transcription (Cyclin D1 and trefoil factor 1 (TFF1)), rapid DNA synthesis and late effects on cell growth. These results introduced a new mechanism for Shp2 oncogenic action and shed new light on extranuclear ER-initiated action in breast tumorigenesis by identifying a novel associated protein, Shp2, for extranuclear ER pathway, which might benefit the therapy of breast cancer.

A prognosis classifier for breast cancer based on conserved gene regulation between mammary gland development and tumorigenesis: a multiscale statistical model.

Identification of novel cancer genes for molecular therapy and diagnosis is a current focus of breast cancer research. Although a few small gene sets were identified as prognosis classifiers, more powerful models are still needed for the definition of effective gene sets for the diagnosis and treatment guidance in breast cancer. In the present study, we have developed a novel statistical approach for systematic analysis of intrinsic correlations of gene expression between development and tumorigenesis in mammary gland. Based on this analysis, we constructed a predictive model for prognosis in breast cancer that may be useful for therapy decisions. We first defined developmentally associated genes from a mouse mammary gland epithelial gene expression database. Then, we found that the cancer modulated genes were enriched in this developmentally associated genes list. Furthermore, the developmentally associated genes had a specific expression profile, which associated with the molecular characteristics and histological grade of the tumor. These result suggested that the processes of mammary gland development and tumorigenesis share gene regulatory mechanisms. Then, the list of regulatory genes both on the developmental and tumorigenesis process was defined an 835-member prognosis classifier, which showed an exciting ability to predict clinical outcome of three groups of breast cancer patients (the predictive accuracy 64∼72%) with a robust prognosis prediction (hazard ratio 3.3∼3.8, higher than that of other clinical risk factors (around 2.0-2.8)). In conclusion, our results identified the conserved molecular mechanisms between mammary gland development and neoplasia, and provided a unique potential model for mining unknown cancer genes and predicting the clinical status of breast tumors. These findings also suggested that developmental roles of genes may be important criteria for selecting genes for prognosis prediction in breast cancer.

Novel neuromorphic CMOS device array for biochemical charge sensing.

Novel neuromorphic CMOS device is proposed as a biochemical charge sensor. The basic architecture of an extended floating-gate field-effect transistor (FET) is modified to be suited for large-array applications. The FET has a floating-gate that is umbrella-shaped (UGFET), maximizing its charge sensing area in a much reduced transistor area. Compared to previous chemoreceptive FET-based charge sensors, the UGFET shows improved scalability and sensitivity. 3-D device simulations validate the UGFET model. The design is fabricated in a standard CMOS process and characterized. Experimental results on biochemical charge sensing are presented employing the transconductance and subthreshold measurement schemes.