ETV7 promotes colorectal cancer progression through upregulation of IFIT3.

Members of the E26 transformation-specific (ETS) variant transcription factor family act as either tumor suppressors or oncogenic factors in numerous types of cancer. ETS variant transcription factor 7 (ETV7) participates in the development of malignant tumors, whereas its involvement in colorectal cancer (CRC) is less clear. In this study, The Cancer Genome Atlas (TCGA) and immunochemistry staining were applied to check the clinical relevance of ETV7 and interferon-induced protein with tetratricopeptide repeats 3 (IFIT3) in CRC patients. Overexpression and knockdown of ETV7 and IFIT3 were conducted by transfecting the cells with pCDNA3.1 plasmids and siRNAs, respectively. Western blotting was used to detect the protein expression of ETV7 in CRC cells. Cell Counting Kit-8, cell colony formation, and Transwell assays, as well as flow cytometry, were used to evaluate the proliferation, migration, cell cycle, and apoptosis of CRC cells. Furthermore, western blotting, RT-qPCR, and luciferase assay were used to explore the regulation of ETV7 on IFIT3. Rescue assay was used to investigate the significance of ETV7/IFIT3 axis on CRC progression. We found that ETV7 was upregulated in CRC tissues and cells. Overexpression of ETV7 stimulated the proliferation, migration, and cell cycle amplification, and reduced the apoptosis of CRC cells. Downregulation of ETV7 exerted the opposite effect on CRC cell progression. Moreover, we demonstrated that ETV7 stimulated the transcription activity, the mRNA and protein expression of IFIT3 in CRC cells. There was a positive correlation between ETV7 and IFIT3 in CRC patients. IFIT3 knockdown reversed the promotive effect exerted by overexpression of ETV7 on the amplification and migration of CRC cells. By contrast, overexpression of IFIT3 blocked the inhibitory effect of ETV7-targeting siRNA. In summary, ETV7 induces progression of CRC by activating the transcriptional expression of IFIT3. The EVT7/IFIT3 axis may be a novel target for CRC therapy.

Performances and enhanced mechanisms of nitrogen removal in a submerged membrane bioreactor coupled sponge iron system.

Sponge iron is a potential material for nitrogen removal, but lack of a study about nitrogen removal in a membrane bioreactor (MBR) coupled with sponge iron. The performances and mechanisms of nitrogen removal of SI-MBR were investigated and compared it with that in GAC-MBR. The results showed that the average rate of organic matter removal in the SI-MBR was 92.74%, which was higher than that in the GAC-MBR (87.48%). And the average effluent NO2--N and NO3--N concentration in the SI-MBR (0.02 mg/L and 3.73 mg/L) was lower than that in the GAC-MBR (0.05 mg/L and 7.51 mg/L). Meanwhile, the highest nitrification rate and denitrification rate was respectively 3.544 ± 0.25 mg/(g VSS·h) and 6.643 ± 0.2 mg/(g VSS·h) in the SI-MBR, which was higher than that (3.094 ± 0.25 mg/(g VSS·h) and (6.376 ± 0.2 mg/(g VSS·h)) in the GAC-MBR. Additionally, the bacterial activities (e.g., DHA activity and respiratory activity) were obviously enhanced through the iron ion from sponge iron. The bacterial community in the SI-MBR system was more richness and diverse than that in the GAC-MBR. Ultimately, the mechanisms of enhanced biological nitrogen removal with sponge iron in MBR were analyzed. On the surface of sponge iron, the DIRB and FOB could use the iron ion from sponge iron as the electron transfer to improve the nitrogen and organic removal. With sponge iron, there is not only the nitrification bacteria and heterotrophic denitrifying microorganism enriched, but also the autotrophic denitrifying bacteria abounded obviously. The autotrophic denitrifying bacteria could use Fe(II) as an electron donor to achieve denitrification and enhance the nitrogen removal.

Coupling of membrane-based bubbleless micro-aeration for 2,4-dinitrophenol degradation in a hydrolysis acidification reactor.

Micro-aeration hydrolysis acidification (HA) is an effective method to enhance the removal of toxic and refractory organic matter, but the difficulty in stable dosing control of trace oxygen limits its wide application. Membrane-based bubbleless aeration has been proved as an ideal aeration method because of its higher oxygen transfer rate, more uniform mass transfer, and lower cost than HA. However, the available information on its application in HA is limited. In this study, membrane-based bubbleless micro-aeration coupled with hydrolysis acidification (MBL-MHA) was exploited to investigate the performance of 2,4-dinitrophenol (2,4-DNP) degradation via comparing it with bubble micro-aeration HA (MHA) and anaerobic HA. The results indicated that the performances in MBL-MHA and MHA were higher than those in HA during the experiment. 2,4-DNP degradation rates under redox microenvironments caused by counter-diffusion in MBL-MHA (84.43∼97.28%) were higher than those caused by co-diffusion in MHA (82.41∼94.71%) under micro-aeration of 0.5-5.0 mL air/min. The 2,4-DNP degradation pathways in MBL-MHA were nitroreduction, deamination, aromatic ring cleavage, and fermentation, while those in MHA were hydroxylation, aromatic ring cleavage, and fermentation. Reduction/oxidation-related, interspecific electron transfer-related species, and fermentative species in MBL-MHA were more abundant than that in MHA. Ultimately, more reducing/oxidizing forces formed by more redox proteins/enzymes from these rich species could enhance 2,4-DNP degradation in MBL-MHA.

Pleckstrin 2 is a potential drug target for colorectal carcinoma with activation of APC/ß­catenin.

The tumor suppressor gene adenomatous polyposis coli (APC) is frequently inactivated or absent in colorectal carcinoma (CRC). Loss­of­function of APC promotes the expression of ß­catenin, which is critical for CRC development. Since ß­catenin acts as an important transcription factor, blockage of ß­catenin may have side effects, including impairment of tissue homeostasis and regeneration, thus limiting the application of ß­catenin inhibitors for the treatment of patients with CRC. Therefore, identifying a novel substrate of APC/ß­catenin may provide essential clues to develop effective drugs. Small interfering RNA technology and lentivirus­mediated overexpression were performed for knockdown and overexpression of pleckstrin 2 (PLEK2) in CRC cells. Cell Counting Kit­8 and colony formation assays, and cell cycle analysis and cell apoptosis detection were used to detect the capacity of cell proliferation, cell cycle distribution and apoptosis. The present study demonstrated that the APC/ß­catenin signaling cascade transcriptionally activated PLEK2 in CRC cells. PLEK2 expression was markedly increased in CRC tissues. There was an inverse correlation between APC and PLEK2 expression in patients with CRC. In vitro, overexpression of PLEK2 increased the proliferation of CRC cells. Opposite results were observed in the cells with knockdown of PLEK2. Furthermore, PLEK2 promoted cell cycle progression and suppressed apoptosis. In summary, upregulation of PLEK2 contributed to CRC proliferation and colony formation activated by the APC/ß­catenin signal pathway. Targeting PLEK2 may be important for the treatment of patients with CRC with activation of the APC/ß­catenin signaling pathway.

Copper induces oxidative stress and apoptosis through mitochondria-mediated pathway in chicken hepatocytes.

The aim of this study was to investigate the effects of excessive copper (Cu)-induced cytotoxicity on oxidative stress and mitochondrial apoptosis in chicken hepatocytes. Chicken hepatocytes were cultured in medium in the absence and presence of copper sulfate (CuSO4) (10, 50, 100 µM), in N-acetyl-L-cysteine (NAC) (1 mM), and the combination of CuSO4 and NAC for 24 h. Morphologic observation and function, reactive oxygen species (ROS) level, antioxidant indices, nitric oxide (NO) content, mitochondrial membrane potential (MMP), and apoptosis-related mRNA and protein levels were determined. These results indicated that excessive Cu could induce release of intracellular lactate dehydrogenase (LDH), aspartate aminotransferase (AST), and alanine aminotransferase (ALT); increase levels of ROS, superoxide dismutase (SOD), malondialdehyde (MDA), catalase (CAT), lipid peroxidation (LPO), and NO; decrease glutathione (GSH) content and MMP; upregulated Bak1, Bax, CytC, and Caspase3 mRNA and protein expression, inhibited Bcl2 mRNA and protein expression, and induced cell apoptosis in a dose effect. The Cu-caused changes of all above factors were alleviated by treatment with NAC. These results suggested that excessive Cu could induce oxidative stress and apoptosis via mitochondrial pathway in chicken hepatocytes.

Design and synthesis of natural product derivatives with selective and improved cytotoxicity based on a sesquiterpene scaffold.

Brasilamide E (1) is a bisabolane sesquiterpenoid isolated from the solid-substrate fermentation cultures of a plant endophytic fungus Paraconiothyrium brasiliense. The compound specifically inhibited proliferation of the MCF-7 cells, but did not show cytotoxicity towards the negative controls HaCaT and NIH3T3 cells (IC50>50 µM). To improve its potency while maintain selectivity, a total of 27 derivatives of 1 were designed, synthesized, and evaluated for in vitro cytotoxicity against six tumor cell lines and the negative control NIH3T3 cells. Among these compounds, compound 12b showed significantly improved potency against the MCF-7, HeLa, and HO8910 cells with IC50 values of 0.13-0.25 µM compared to 1 (IC50 8.47-18.00 µM), and remained nontoxic to the NIH3T3 cells.

Two new ramulosin derivatives from the entomogenous fungus Truncatella angustata.

Two new ramulosin derivatives, 7α-hydroxy-8-dihydroramulosin (1) and 7-ketoramulosin (2), along with three known metabolites, (+)-ramulosin (3), 6-hydroxyramulosin (4), and 8-dihydroramulosin (5), were isolated from the crude extract of Truncatella angustata, an entomogenous fungus isolated from the Septobasidium-infected insect Aspidiotus sp. The structures of 1 and 2 were elucidated by nuclear magnetic resonance experiments, and 1 was further confirmed by X-ray crystallography. The absolute configuration of 1 was assigned by single-crystal X-ray diffraction analysis using Cu Kα radiation, whereas that of 2 was determined by electronic circular dichroism (ECD) calculations. Compounds 1-5 were tested for cytotoxicity against four human carcinoma cell lines, HeLa, A549, MCF-7, and T24. Compound 4 showed weak cytotoxic effects against A549 and T24.