Protrusion-localized STAT3 mRNA promotes metastasis of highly metastatic hepatocellular carcinoma cells in vitro.

AIM: Recent evidence shows that localization of mRNAs and their protein products at cellular protrusions plays a decisive function in the metastasis of cancer cells. The aim of this study was to identify the variety of proteins encoded by protrusion-localized mRNAs and their roles in the metastasis and invasion of liver cancer cells. METHODS: Highly metastatic hepatocellular carcinoma cell line HCCLM3 and non-metastatic hepatocellular carcinoma cell line SMMC-7721 were examined. Cell protrusions (Ps) were separated from cell bodies (CB) using a Boyden chamber assay; total mRNA population in CB and Ps fractions was analyzed using high-throughput direct RNA sequencing. The localization of STAT3 mRNA and protein at Ps was confirmed using RT-qPCR, RNA FISH, and immunofluorescence assays. Cell migration capacity and invasiveness of HCCLM3 cells were evaluated using MTT, wound healing migration and in vitro invasion assays. The interaction between Stat3 and growth factor receptors was explored with co-immunoprecipitation assays. RESULTS: In HCCLM3 cells, 793 mRNAs were identified as being localized in the Ps fraction according to a cut-off value (Ps/CB ratio) >1.6. The Ps-localized mRNAs could be divided into 4 functional groups, and were all closely related to the invasive and metastatic properties. STAT3 mRNA accumulated in the Ps of HCCLM3 cells compared with non-metastatic SMMC-7721 cells. Treatment of HCCLM3 cells with siRNAs against STAT3 mRNA drastically decreased the cell migration and invasion. Moreover, Ps-localized Stat3 was found to interact with pseudopod-enriched platelet-derived growth factor receptor tyrosine kinase (PDGFRTK) in a growth factor-dependent manner. CONCLUSION: This study reveals STAT3 mRNA localization at the Ps of metastatic hepatocellular carcinoma HCCLM3 cells by combining application of genome-wide and gene specific description and functional analysis.

[Association of combined polymorphisms in MIP-1α and ApoE genes with the susceptibility of inflammatory bowel disease].

OBJECTIVE: To investigate whether the macrophage inflammatory protein 1 alpha (MIP-1α) and apolipoprotein E (ApoE) gene polymorphisms, either alone or in combination, affect the susceptibility to inflammatory bowel disease (IBD). METHODS: Genomic DNA of IBD patients with Crohn's disease (CD, n = 41) and with ulcerative colitis (UC, n = 142) and healthy controls (n = 160) was extracted and genotyped for the MIP-1α and ApoE gene polymorphisms by restriction fragment length polymorphism assay. RESULTS: MIP-1α -906(TA)(6)/(TA)(6) homozygotes had a significantly elevated risk of UC (OR = 1.909, 95%CI = 1.204 - 3.028). The carriers of APOE4ε4 were at a significantly higher risk for UC with OR of 2.379 (95% CI = 1.451 - 3.896). And a combination of these two loci, MIP-1α -906(TA)(6)/(TA)(6)/APOE4ε4 were strongly associated with a higher risk of UC (OR = 3.288; 95%CI = 1.777 - 6.084). CONCLUSION: The polymorphisms of MIP-1α -906 (TA)(6)/(TA)(6) and ApoE are probably independent genetic risk factors for UC. And the coexistence of both may exert an additive effect on the UC risks.

[Association of IL-8 gene polymorphisms with inflammatory bowel disease in Chinese patients].

OBJECTIVE: To investigate the association of interleukin 8 (IL-8) gene polymorphisms with the risks of inflammatory bowel disease (IBD). METHODS: Single nucleotide polymorphisms (SNPs) of IL-8 gene at -845 T/C, -738 T/A, -353 A/T, -251 T/A and +678 T/C were analyzed in 183 IBD patients. They included Crohn's disease (CD, n = 41), ulcerative colitis (UC, n = 142) and healthy controls (n = 160). The methods of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and polymerase chain reaction-sequence specific primers (PCR-SSP) were employed. RESULTS: No association was observed between any of these five SNPs in IL-8 gene with the occurrence of IBD. A specific haplotype AAT (-353 A/T, -251 T/A & +678 T/C) was over-represented in UC cases when compared with controls (31.0% vs 23.7%, P = 0.046). But the distributions of this haplotype did not show significant difference between CD cases and controls. CONCLUSION: Our data support a significant but modest association between the AAT haplotype of IL-8 gene and UC (OR = 1.441, 95%CI 1.007 - 2.063).

Postoperative plasma copeptin levels independently predict delirium and cognitive dysfunction after coronary artery bypass graft surgery.

Copeptin can reflect individual's stress state and are correlated with poor outcome of critical illness. The occurrence of postoperative delirium (POD) and cognitive dysfunction (POCD) is associated with worse outcome after coronary artery bypass graft (CABG) surgery. The present study aimed to investigate the ability of postoperative plasma copeptin level to predict POD and POCD in patients undergoing CABG surgery. Postoperative plasma copeptin levels of 108 patients were measured by an enzyme-linked immunosorbent assay. It was demonstrated that plasma copeptin levels were substantially higher in patients with POD than without POD (1.8±0.6 ng/mL vs. 1.1±0.3 ng/mL; P<0.001) and in patients with POCD than without POCD (1.9±0.6 ng/mL vs. 1.1±0.4 ng/mL; P<0.001). Plasma copeptin level and age were identified as independent predictors for POD [odds ratio (OR), 67.386; 95% confidence interval (CI), 12.031-377.426; P<0.001 and OR, 1.202; 95% CI, 1.075-1.345; P=0.001] and POCD (OR, 28.814; 95% CI, 7.131-116.425; P<0.001 and OR, 1.151; 95% CI, 1.030-1.285; P=0.003) using a multivariate analysis. For prediction of POD, the area under receiver operating characteristic curve (AUC) of the copeptin concentration (AUC, 0.883; 95% CI, 0.807-0.937) was markedly higher than that of age (AUC, 0.746; 95% CI, 0.653-0.825; P=0.020). For prediction of POCD, the AUC of the copeptin concentration (AUC, 0.870; 95% CI, 0.792-0.927) was markedly higher than that of age (AUC, 0.735; 95% CI, 0.641-0.815; P=0.043). Thus, postoperative plasma copeptin level may be a useful, complementary tool to predict POD and POCD in patients undergoing CABG surgery.

Gene expression profiling of Clostridium botulinum under heat shock stress.

During growth, C. botulinum is always exposed to different environmental changes, such as temperature increase, nutrient deprivation, and pH change; however, its corresponding global transcriptional profile is uncharacterized. This study is the first description of the genome-wide gene expression profile of C. botulinum in response to heat shock stress. Under heat stress (temperature shift from 37°C to 45°C over a period of 15 min), 176 C. botulinum ATCC 3502 genes were differentially expressed. The response included overexpression of heat shock protein genes (dnaK operon, groESL, hsp20, and htpG) and downregulation of aminoacyl-tRNA synthetase genes (valS, queA, tyrR, and gatAB) and ribosomal and cell division protein genes (ftsZ and ftsH). In parallel, several transcriptional regulators (marR, merR, and ompR families) were induced, suggesting their involvement in reshuffling of the gene expression profile. In addition, many ABC transporters (oligopeptide transport system), energy production and conversion related genes (glpA and hupL), cell wall and membrane biogenesis related genes (fabZ, fabF, and fabG), flagella-associated genes (flhA, flhM, flhJ, flhS, and motAB), and hypothetical genes also showed changed expression patterns, indicating that they may play important roles in survival under high temperatures.

Transcriptome analysis of adaptive heat shock response of Streptococcus thermophilus.

Streptococcus thermophilus, a gram-positive facultative anaerobe, is one of the most important lactic acid bacteria widely used in the dairy fermentation industry. In this study, we have analyzed the global transcriptional profiling of S. thermophilus upon temperature change. During a temperature shift from 42°C to 50°C, it is found that 196 (10.4%) genes show differential expression with 102 up-regulated and 94 down-regulated at 50°C. In particular, 1) Heat shock genes, such as DnaK, GroESL and clpL, are identified to be elevated at 50°C; 2) Transcriptional regulators, such as HrcA, CtsR, Fur, MarR and MerR family, are differentially expressed, indicating the complex molecular mechanisms of S. thermophilus adapting to heat shock; 3) Genes associated with signal transduction, cell wall genes, iron homeostasis, ABC transporters and restriction-modification system were induced; 4) A large number of the differentially expressed genes are hypothetical genes of unknown function, indicating that much remains to be investigated about the heat shock response of S. thermophilus. Experimental investigation of selected heat shock gene ClpL shows that it plays an important role in the physiology of S. thermophilus at high temperature and meanwhile we confirmed ClpL as a member of the CtsR regulon. Overall, this study has contributed to the underlying adaptive molecular mechanisms of S. thermophilus upon temperature change and provides a basis for future in-depth functional studies.