FNDC5 inhibits malignant growth of human cervical cancer cells via restraining PI3K/AKT pathway.

Cervical cancer (CxCa) is the fourth most frequent cancer in women. This study aimed to determine the role and underlying mechanism of fibronectin type III domain-containing protein 5 (FNDC5) in inhibiting CxCa growth. Experiments were performed in human CxCa tissues, human CxCa cell lines (HeLa and SiHa), and xenograft mouse model established by subcutaneous injection of SiHa cells in nude mice. Bioinformatics analysis showed that CxCa patients with high FNDC5 levels have a longer overall survival period. FNDC5 expression was increased in human CxCa tissues, HeLa and SiHa cells. FNDC5 overexpression or FNDC5 protein not only inhibited proliferation, but also restrained invasion and migration of HeLa and SiHa cells. The effects of FNDC5 were prevented by inhibiting integrin with cilengitide, activating PI3K with recilisib or activating Akt with SC79. FNDC5 inhibited the phosphorylation of PI3K and Akt, which was attenuated by recilisib. PI3K inhibitor LY294002 showed similar effects to FNDC5 in HeLa and SiHa cells. Intravenous injection of FNDC5 (20 µg/day) for 14 days inhibited the tumor growth, and reduced the proliferation marker Ki67 expression and the Akt phosphorylation in the CxCa xenograft mouse model. These results indicate that FNDC5 inhibits the malignant phenotype of CxCa cells through restraining PI3K/Akt signaling. Upregulation of FNDC5 may play a beneficial role in retarding the tumor growth of CxCa.

MiR-21-3p in extracellular vesicles from vascular fibroblasts of spontaneously hypertensive rat promotes proliferation and migration of vascular smooth muscle cells.

Enhanced proliferation and migration of vascular smooth muscle cells (VSMCs) contributes to vascular remodeling in hypertension. Adventitial fibroblasts (AFs)-derived extracellular vesicles (EVs) modulate vascular remodeling in spontaneously hypertensive rat (SHR). This study shows the important roles of EVs-mediated miR-21-3p transfer in VSMC proliferation and migration and underlying mechanisms in SHR. AFs and VSMCs were obtained from aorta of Wistar-Kyoto rat (WKY) and SHR. EVs were separated from AFs culture with ultracentrifugation method. MiR-21-3p content in the EVs of SHR was increased compared with those of WKY. MiR-21-3p mimic promoted VSMC proliferation and migration of WKY and SHR, while miR-21-3p inhibitor attenuated proliferation and migration only in the VSMCs of SHR. EVs of SHR stimulated VSMC proliferation and migration, which were attenuated by miR-21-3p inhibitor. Sorbin and SH3 domain containing 2 (SORBS2) mRNA and protein levels were reduced in the VSMCs of SHR. MiR-21-3p mimic inhibited, while miR-21-3p inhibitor promoted SORBS2 expressions in the VSMCs of both WKY and SHR. EVs of SHR reduced SORBS2 expression, which was prevented by miR-21-3p inhibitor. EVs of WKY had no significant effect on SORBS2 expressions. SORBS2 overexpression attenuated the roles of miR-21-3p mimic and EVs of SHR in promoting VSMC proliferation and migration of SHR. Overexpression of miR-21-3p in vivo promotes vascular remodeling and hypertension. These results indicate that miR-21-3p in the EVs of SHR promotes VSMC proliferation and migration via negatively regulating SORBS2 expression.

Interference of PTK6/GAB1 signaling inhibits cell proliferation, invasion, and migration of cervical cancer cells.

Protein tyrosine kinase 6 (PTK6) has shown important cancer­promoting effects in a variety of cancer types. Nonetheless, its vital role in cervical cancer has not been completely elucidated. The present study sought to address whether PTK6 is involved in the malignant progression of cervical cancer via its interaction with GRB2­associated binding 1 (GAB1). Western blotting was used to examine PTK6 and GAB1 expression levels. Cell Counting Kit­8, Transwell, wound healing, and terminal deoxynucleotidyl­transferase­mediated dUTP nick end labeling assays were performed to estimate the corresponding proliferative, migratory, invasive, and apoptotic abilities of the cells. Co­immunoprecipitation (Co­IP) assays confirmed binding of PTK6 to GAB1. The results revealed that the expression levels of PTK6 and GAB1 were markedly increased in cervical cancer cell lines compared with those noted in normal cervical epithelial cells. The cell proliferative, invasive, and migratory activities of cervical cancer cells were reduced in the absence of PTK6 expression, whereas the induction of apoptosis was aggravated under these conditions. The results of the Co­IP assay indicated that PTK6 expression was positively associated with GAB1. In addition, the suppressive effect of PTK6 silencing on the malignant phenotypes of cervical cancer cells was reversed following overexpression of GAB1. In summary, the present study indicated that knockdown of PTK6 expression protected against the malignant progression of cervical cancer, while overexpression of GAB1 counteracted the inhibitory effects of PTK6 knockdown on cervical cancer cells.

The impact of ship emissions on PM2.5 and the deposition of nitrogen and sulfur in Yangtze River Delta, China.

Ship emissions contribute significantly to the deterioration of air quality, while their impacts on ambient PM2.5 and depositions have not been comprehensively evaluated. This is especially true for China because it has a long coastline, busy shipping routes and many large ports. To fill this gap, this study applied the SMOKE/WRF/CMAQ modeling system to quantifying the impacts of ships on PM2.5 compositions, annual and seasonal contribution to PM2.5 as well as the wet and dry deposition of nitrogen and sulfur compounds over the land areas in YRD region for 2014. The results showed that 4.0% of annual PM2.5 concentrations over the land areas could be explained by ship emissions and the largest contribution could reach up to 35.0% in port areas. Temporally, the contribution to PM2.5 exhibited an obviously seasonal variation. The highest contribution was predicted in autumn (6.2%), followed by summer (5.4%), spring (3.6%) and winter (1.2%) for the land areas. Spatially, the contribution reached up to 13.6% along the coastline and dropped to 2.1% 300 km inland. As for the impacts on PM2.5 components, the primary components were relatively small and increased mainly along the shipping routes and the Yangtze River, whereas the secondary components played a more important role in both water and land areas. The sulfur deposition due to ship emissions was occurred generally along the shipping routes and was dominated by the dry SO2 deposition. The nitrogen depositions, on the contrary, was observed not only along the shipping routes but also extend to wide land areas. Further investigation revealed that ship emissions have caused an evident increase of dry nitrogen deposition in NO2 and HNO3, while a slight decrease in NH3 over YRD region. These results indicated that comprehensive regulations of ship emissions are required considering their adverse effects on the ambient concentration of PM2.5 and the deposition of sulfur and nitrogen.

Characteristics of N2O production and hydroxylamine variation in short-cut nitrification SBR process.

In order to study the characteristics of nitrous oxide (N2O) production and hydroxylamine (NH2OH) variation under oxic conditions, concentrations of NH2OH and N2O were simultaneously monitored in a short-cut nitrification sequencing batch reactor (SBR) operated with different influent ammonia concentrations. In the short-cut nitrification process, N2O production was increased with the increasing of ammonia concentration in influent. The maximum concentrations of dissolved N2O-N in the reactor were 0.11 mg/L and 0.52 mg/L when ammonia concentrations in the influent were 50 mg/L and 70 mg/L respectively. Under the low and medium ammonia load phases, the concentrations of NH2OH-N in the reactor were remained at a low level which fluctuated around 0.06 mg/L in a small range, and did not change with the variation of influent NH4+-N concentration. Based on the determination results, the half-saturation of NH2OH in the biochemical conversion process of NH2OH to NO2--N was very small, and the value of 0.05 mg NH2OH-N/L proposed in the published literature was accurate. NH2OH is an important intermediate in the nitrification process, and the direct determination of NH2OH in the nitrification process was beneficial for revealing the kinetic process of NH2OH production and consumption as well as the effects of NH2OH on N2O production in the nitrification process.

Mathematical modeling of nitrous oxide production in an anaerobic/oxic/anoxic process.

This study incorporates three currently known nitrous oxide (N2O) production pathways: ammonium-oxidizing bacteria (AOB) denitrification, incomplete hydroxylamine (NH2OH) oxidation, and heterotrophic denitrification on intracellular polymers, into a mathematical model to describe N2O production in an anaerobic/oxic/anoxic (AOA) process for the first time. The developed model was calibrated and validated by four experimental cases, then evaluated by two independent anaerobic/aerobic (AO) studies from literature. The modeling results displayed good agreement with the measured data. N2O was primarily generated in the aerobic stage by AOB denitrification (67.84-81.64%) in the AOA system. Smaller amounts of N2O were produced via incomplete NH2OH oxidation (15.61-32.17%) and heterotrophic denitrification on intracellular polymers (0-12.47%). The high nitrite inhibition on N2O reductase led to the increased N2O accumulation in heterotrophic denitrification on intracellular polymers. The new model was capable of modeling nitrification-denitrification dynamics and heterotrophic denitrification on intracellular polymers in the AOA system.