High Expression of FAM83B Predicts Poor Prognosis in Patients with Pancreatic Ductal Adenocarcinoma and Correlates with Cell Cycle and Cell Proliferation.

FAM83B (family with sequence similarity 83, member B) seems to emerge as a new class of players involved in the development of a variety of malignant tumors. Yet the molecular mechanisms are not well understood. The present study is intended to investigate the expression and function of FAM83B in pancreatic ductal adenocarcinoma (PDAC). In this study, we found that the expression of FAM83B was significantly increased both in PDAC cell lines and PDAC tumor tissues. FAM83B expression was positively related with advanced clinical stage and poor vital status. Higher FAM83B expression predicted shorter overall survival in PDAC patients, regardless of lymphatic metastasis status and histological differentiation. Actually, FAM83B may act as an independent prognostic indicator as well. What's more, down-regulation of FAM83B in PDAC cells contributed to G0/G1 phase arrest and inhibition of cell proliferation. Finally, a subcutaneous xenograft model indicated that knockdown of FAM83B significantly reduced the tumor volume in vivo. Our findings have provided supporting evidence for the potential molecular biomarker role of FAM83B in PDAC. It's of great interest and broad significance to target FAM83B in PDAC, which may conduce to develop a meaningful and effective strategy in the diagnosis and treatment of PDAC.

Suppression of gastric cancer growth by baculovirus vector-mediated transfer of normal epithelial cell specific-1 gene.

AIM: To study the inhibitory effect of baculovirus-mediated normal epithelial cell specific-1 (NES1) gene therapy on gastric cancer (GC) in vitro and in vivo. METHODS: We first constructed recombinant baculovirus vectors and then transfected them into gastric cancer cells (SGC-7901). Efficiency of the baculovirus for gene transfer into SGC-7901 cells and cell growth curves were detected by fluorescence microscopy, Western blot and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in vitro, respectively. The therapeutic effect of this gene therapy on GC was confirmed in xenografted nude mice. Tumor growth was determined by tumor volume, and expression of NES1 in tumor was analyzed by immunohistochemistry. RESULTS: Baculovirus vectors were successfully transfected into SGC-7901 cells. SGC-7901 cells transfected with the NES1 gene inhibited cell growth. In the Bac-NES1 treated group, tumor growth was significantly reduced with a high level of NES1 expression CONCLUSION: Baculovirus-mediated NES1 gene can be used in gene therapy for GC.

Angiotensin II type 1 receptor expression in human gastric cancer and induces MMP2 and MMP9 expression in MKN-28 cells.

Angiotensin II (Ang II), a main effector peptide in the renin-angiotensin system, acts as a growth-promoting and angiogenic factor via angiotensin II receptor1 (AT1R). In this study, we investigated the expression of angiotensin II type1 receptor (AT1R) in gastric cancer and the effects of Ang II on the expression of MMP2 and MMP9 in the human gastric cancer cell line MKN-28 cells. The expression of the Ang II type I receptor was examined by western and immunocytochemistry in gastric cancer cell lines and detected by real-time PCR and immunohistochemistry in normal and gastric cancer tissues. The expression of MMP2 and MMP9 were detected by real-time PCR and western after treatment with Ang II and/or AT1R antagonist. AT1R were expressed in all human gastric cancer lines and the expression of AT1R was significantly higher in cancer tissues than that in normal gastric tissues (P < 0.01). Furthermore, Ang II promoted the expression of MMP2 and MMP9 in MKN-28 cells, and the stimulatory effects of Ang II could be blocked by AT1R antagonist. These results suggest that AT1R is involved in the progression of gastric cancer and may promote the angiogenesis of gastric cancer cell line (MKN-28), and these effects may be associated with the upregulation of MMP2 and MMP9.

Angiotensin II type 1 receptor antagonist suppress angiogenesis and growth of gastric cancer xenografts.

Angiotensin II (Ang II) has been reported to promote tumor progression, tumor growth and angiogenesis in many cancers. We previously observed that angiotensin II type 1 receptors (AT1R) were upregulated in human gastric cancer and may be involved in the progression of gastric cancer. We studied the effects of AT1R antagonist on angiogenesis and growth in gastric cancer xenografts to observe the mechanism action of AT1R in the gastric cancer. The results showed that the growth of gastric cancer cells was significantly suppressed by treatment with AT1R antagonist. In vivo, TCV-116, at doses of both 2 and 5 mg/kg/day, significantly suppressed tumor growth in mice (47.3 and 70.2%). Microvessel density was significantly decreased by TCV-116 (3.4 +/- 0.9 and 2.8 +/- 0.5 per field) compared with the control group (12.9 +/- 1.1 per field), and VEGF expression was significantly suppressed by AT1R antagonist. These results demonstrate that AT1R plays an important role in the progression of gastric cancer. Suppression tumor angiogenesis could be one of the mechanisms by which AT1R antagonist suppresses the growth of gastric cancer. These findings also provide a theoretical basis for the future clinical application of AT1R antagonist against gastric cancer.

[Experimental study of baculovirus-mediated transfection of spiral ganglion cells in rats].

OBJECTIVE: To study the feasibility and the characteristics of recombinant baculovirus as spiral ganglion cells (SGC) gene transfer vector. METHODS: After the generation of baculovirus- green fluorescent protein( Bac-GFP) according to Bac-to-Bac baculovirus expression system, SGC were infected by Bac-GFP with different multiplicities of infection (MOI) and different concentrations of sodium butyrate. The transfection cell rate and mean fluorescence strength (MFS) were detected by fluorescence microscopy and flow cytometry. Toxicity effects of recombinant baculovirus vectors and sodium butyrate on SGC were determined by spectroscopic measurement of 3-(4, 5)-dimethylthiahiazo (-z-y1)-3, 5-diphenytetrazoliumromide (MTF). RESULTS: Baculovirus was able to infect primary SGC cultures. The dose-response characteristics of Bac-GFP were determined on SGC, and the expression level could be up-regulated by sodium butyrate. Infection with Bac-GFP in the absence or presence of sodium butyrate (< or =10 mmol/L) was considered to be non-cytotoxic to primary SGC. GFP had been expressed in SGC at 6 h post-infection and the highest numbers of cells expressing GFP were observed at approximately 48 h post-infection. CONCLUSIONS: Baculovirus is a novel and promising tool for gene transferring into the cochlear nervous system both for studies of the function of foreign genes and the development of gene therapy strategies.

Downregulation and CpG island hypermethylation of NES1/hK10 gene in the pathogenesis of human gastric cancer.

The normal epithelial cell-specific-1 (NES1)/Kallikrein 10 gene is proposed to be a novel putative tumor suppressor gene in several malignant diseases. The role of NES1 gene in gastric cancer has not been fully understood. Our study revealed that CpG island hypermethylation plays an important role in the downregulation of NES1 mRNA expression in gastric cancer. In situ hybridization showed that loss or reduction of NES1 mRNA expression is associated with differentiation level during tumor progression suggesting that NES1 inactivation might contribute to the malignant progression of human gastric cancers.