Exploring Integrin-Mediated Force Transmission during Confined Cell Migration by DNA-Based Tension Probes.

Mechanical forces have profound effects on the morphology and migration of cells in a two-dimensional environment. However, cells in vivo mostly migrate in three-dimensional space while physically constrained, and the mechanism by which cellular dynamic forces drive migration in this confined environment is unclear. Here, we present a method of fabricating microfluidic chips with integrated DNA-based tension probes to measure spatiotemporal variations in integrin-mediated force exerted during confined cell migration. Using this developed device, we measured the spatial locations, magnitudes, and temporal characteristics of integrin-ligand tension signals in motile cells in different microchannels and found that cells exerted less force and underwent increasingly transitory integrin-ligand interactions when migrating in confined spaces. This study demonstrates that the described method provides insights into understanding the migratory machinery of cells in geometrically confined environment that better mimics physiological conditions.

Insights into soil bacterial and physicochemical properties of annual ryegrass-maize rotation (ARMR) system in southern China.

The popularized application of annual ryegrass-maize rotation (ARMR) in southern China has been proposed to fully utilize the farmlands and to increase forage yield and quality. Herein, one growth cycle of ARMR was conducted and soil bacteria were analyzed by 16S rRNA sequencing for control (CK), after the preceding crop (monoculture, or mixed sowing of annual ryegrass and oat) and the successive crop (maize). Our results indicated that the α-diversity of soil bacteria was changed in the ARMR system, which was related to the activity of urease and available phosphatase. The mixed sowing of annual ryegrass and oat in preceding crop could improve the yield and quality, while it was accompanied by unbalanced soil community. With the increased sowing proportion of oat to annual ryegrass, the soil pH increased while the soil available phosphatase decreased. The ARMR system was found to benefit the soil microenvironment by increasing the beneficial soil bacteria and enzyme activity or decreasing the harmful soil bacteria. Considering the soil bacteria α-diversity index and physicochemical properties comprehensively, the recommended sowing regime is the mixed sowing of M2 (22.5 kg·hm-2 annual ryegrass with 75 kg·hm-2 oat).

Comparative Physiological and Proteomic Analysis Reveals Different Involvement of Proteins during Artificial Aging of Siberian Wildrye Seeds.

Seed aging has an important effect on the germplasm preservation and industrialized production of Siberian wildrye (Elymus sibiricus) in the Qinghai-Tibet Plateau. However, so far its underlying molecular mechanisms still largely remain unknown. To shed light on this topic, one-year stored seeds of E. sibiricus were exposed to artificial aging treatments (AAT), followed by seed vigor characteristics and physiological status monitoring. Then global proteomics analysis was undertaken by the tandem mass tags (TMT) technique, and the proteins were quantified with liquid chromatography-tandem mass spectrometry on three aging time points (0 h, 36 h and 72 h). Finally, we verified the expression of related proteins by parallel reaction monitoring (PRM). Our results demonstrated that the seed vigor decreased remarkably in response to artificial aging, but the relative ion-leakage and malondialdehyde content, superoxide anion and hydrogen peroxide showed the opposite situation. Proteomic results showed that a total of 4169 proteins were identified and quantified. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that a series of key pathways including carbohydrate metabolism, lipid metabolism, and antioxidant activity were severely damaged by aging treatments. Numerous key proteins such as glyceraldehyde triphosphate glyceraldehyde dehydrogenase, succinate dehydrogenase, lipoxygenase, peroxidase, glutathione-s-transferase and late embryogenesis abundant proteins were significantly down-regulated. However, the up-regulation of the heat shock protein family has made a positive contribution to oxidative stress resistance in seeds. This study provides a useful catalog of the E. sibiricus proteomes with insights into the future genetic improvement of seed storability.

SATB2 targeted by methylated miR-34c-5p suppresses proliferation and metastasis attenuating the epithelial-mesenchymal transition in colorectal cancer.

OBJECTIVES: SATB2 has been shown to be markedly reduced in colorectal cancer (CRC) tissues relative to paired normal controls; however, the mechanism behind remains not well understood. To investigate why SATB2 was down-regulated in CRC, we attempted to analyse it from the angle of miRNA-mRNA modulation. MATERIALS AND METHODS: SATB2 expression was detected in CRC tissues using immunohistochemistry and verified using real-time PCR on mRNA level, followed by analysis of clinicopathological significance of its expression. Metastatic variation of CRC cells was evaluated both in vivo and in vitro. To find out the potential miRNA that directly regulate the SATB2, luciferase reporter assay was performed following the bioinformatic prediction. RESULTS: SATB2 was confirmed to be closely linked with the metastasis and shorter overall survival of CRC in our own cases. Silencing of SATB2 was shown to be able to promote the metastatic ability of CRC cells in vivo, enhancing the epithelial-mesenchymal transition (EMT). Mechanistically, miR-34c-5p was identified to be a novel miRNA that can directly modulate the SATB2. It turned out that the promoter of miR-34c-5p was methylated, which leads to the repression of miR-34c-5p in CRC. Treatment with 5-Aza-dC can reasonably and significantly restore the level of miR-34c-5p in CRC cells relative to control, thereby down-regulating the SATB2. CONCLUSIONS: Together, our study revealed that SATB2 targeted by methylated miR-34c-5p can suppress the metastasis, weakening the EMT in CRC.

Prognostic role of survivin in renal cell carcinoma: A system review and meta-analysis.

BACKGROUND: Survivin plays an important role in cancer pathogenesis, which has been suggested to be related to poor prognosis in renal cell carcinoma (RCC). We performed a meta-analysis to quantify the prognostic value of survivin in renal cell carcinoma (RCC) patients. PATIENTS AND METHODS: Relevant articles exploring the relationship between survivin expression and survival of RCC patients published up to 10 November 2015 were retrieved in PubMed, Web of science and Cochrane databases. The summary hazard ratio (HR) and 95% confidence interval (CI) were calculated by a random-effects model. RESULTS: A total of 1583 patients from 10 studies were included. The high expression of survivin was associated with poor Overall Survival (OS) in two studies (Pooled HRs=2.77, 95%CI: 1.46-5.26, I(2)=0.0%, P=0.329). Further, meta-analysis of seven studies showed that elevated survivin expression predicted shorter cancer-specific survival (CSS) of RCC (HR=2.85, 95% CI: 2.25-3.61, I(2)=17.6%, P=0.295). Additionally, subgroup analysis showed that survivin over-expression was associated significantly with worse CSS regardless of different source of survivin, sample size, follow-up duration, race and detection method. CONCLUSIONS: A higher survivin expression seems to represent an unfavorable and robust prognostic factor for clinical outcomes in RCC patients.