In Xuan Wei County, Yunnan Province, lung cancer mortality is among China's highest and, especially in females, is more closely associated with indoor burning of "smoky" coal, as opposed to wood or "smokeless" coal, than with tobacco smoking. Indoor air samples were collected during the burning of all three fuels. In contrast to wood and smokeless coal emissions, smoky coal emission has high concentrations of submicron particles containing mutagenic organics, especially in aromatic and polar fractions. These studies suggested an etiologic link between domestic smoky coal burning and lung cancer in Xuan Wei.
A new series of five three-dimensional Ln(III) metal-organic frameworks (MOFs) formulated as [Ln(μ-L)(μ-HCOO)(μ-OH)(μ-O)(DMF)(HO)] {Ln = Tb (1), Eu (2), Gd (3), Dy (4), and Er (5)} was successfully obtained via a solvothermal reaction between the corresponding lanthanide(III) nitrates and 2-(6-carboxypyridin-3-yl)terephthalic acid (HL). All of the obtained compounds were fully characterized, and their structures were established by single-crystal X-ray diffraction. All products are isostructural and possess porous 3D networks of the fluorite topological type, which are driven by the cubane-like [Ln(μ-OH)(μ-O)(μ-HCOO)] blocks and μ-L spacers. Luminescent and sensing properties of 1-5 were investigated in detail, revealing a unique capability of Tb-MOF (1) for sensing acetone and metal(III) cations (Fe or Ce) with high efficiency and selectivity. Apart from a facile recyclability after sensing experiments, the obtained Tb-MOF material features a remarkable stability in a diversity of environments such as common solvents, aqueous solutions of metal ions, and solutions with a broad pH range from 4 to 11. In addition, compound 1 represents a very rare example of the versatile Ln-MOF probe capable of sensing Ce or Fe cations or acetone molecules.
A novel luminescent microporous lanthanide metal-organic framework (Ln-MOF) based on a urea-containing ligand has been successfully assembled. Structural analysis revealed that the framework features two types of 1D channels, with urea N-H bonds projecting into the pores. Luminescence studies have revealed that the Ln-MOF exhibits high sensitivity, good selectivity, and a fast luminescence quenching response towards Fe , Cr anions, and picric acid. In particular, in the detection of Cr O and picric acid, the Ln-MOF can be simply and quickly regenerated, thus exhibiting excellent recyclability. To the best of our knowledge, this is the first example of a multi-responsive luminescent Ln-MOF sensor for Fe , Cr anions, and picric acid based on a urea derivative. This Ln-MOF may potentially be used as a multi-responsive regenerable luminescent sensor for the quantitative detection of toxic and harmful substances.
Metabolic reprogramming is associated with tumorigenesis. However, glucose metabolism in tumors is poorly understood. Here, we report that glucose levels are significantly lower in bulk tumor specimens than those in normal tissues of the same tissue origins. We show that mono-ubiquitinated histone H2B (uH2B) is a semi-quantitative histone marker for glucose. We further show that loss of uH2B occurs specifically in cancer cells from a wide array of tumor specimens of breast, colon, lung and additional 23 anatomic sites. In contrast, uH2B levels remain high in stromal tissues or non-cancerous cells in the tumor specimens. Taken together, our data suggest that glucose deficiency and loss of uH2B are novel properties of cancer cells in vivo, which may represent important regulatory mechanisms of tumorigenesis.
Two novel heptanuclear 3d-4f helicates have been synthesized and characterized. The helicates act as catalysts and show high catalytic activity for the coupling of CO and epoxides to obtain cyclic carbonates with a wide substrate scope at ambient temperature and pressure.
Two novel lanthanide metal–organic framework (Ln‐MOF) luminescent sensors for the detection of picric acid have been successfully assembled. Following a function‐oriented strategy, urea hydrogen‐bonding functional sites were introduced into two MOF frameworks. A structural analysis indicated that the two MOFs have the exact same structure, namely 2D layers with diamond‐shaped holes that are accumulated into a 3D framework through the hydrogen‐bonding interactions between urea and carboxylate groups. Interestingly, only half of the urea units are involved in supporting the MOF framework through N−H⋅⋅⋅O hydrogen‐bonding interactions, whereas the other half are located in the pore channel and act as empty recognition sites. Abundant N−H urea bonds are present in the inner walls of three types of interpenetrating 1D channels. Luminescence studies revealed that the two Ln‐MOFs exhibit high sensitivity, good selectivity, and a fast luminescence quenching response towards picric acid. In particular, the two Ln‐MOFs can be simply and quickly regenerated, and exhibit excellent recyclability. In summary, we have successfully used a function‐oriented strategy to achieve multiple functions in a ligand to construct lanthanide MOF luminescent sensors for the detection of picric acid, thereby providing a potential strategy for the future development of MOF luminescent sensors with a specific target.
Background
Triple-negative breast cancer (TNBC) is a type of breast cancer with a high degree of malignancy. Because of the remarkable biological characteristics of high invasion, metastasis and recurrence, TNBC is often accompanied by a poor prognosis. As a molecular characteristic of TNBC, high expression of CD147 has been confirmed by a large number of studies. However, the mechanism of CD147 expression regulation in TNBC remains elusive. In this study, we investigated the roles of miR-890 in inhibiting CD147.
Methods
Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect CD147 mRNA and miR-890 level, and western blotting was used to detect CD147 protein. Bioinformatics screening and 3′-Untranslated Region (3′-UTR) luciferase assays were used to analyze the microRNAs (miRNA) binding site. Cell proliferation, apoptosis and invasion were assessed by using CCK-8, flow cytometry and transwell assays.
Results
The upregulation of miR-890 inhibited cell proliferation and invasion, induced apoptosis in MDA-MB-231 and HCC-70 TNBC cells by negatively regulating its target gene, CD147, and the upregulation of CD147 rescued the inhibitory effects of miR-890. miR-890 targeted CD147 by binding to its 3′-UTR. Further results showed that the upregulation of miR-890 also inhibited the expression of MMPs, the downstream genes of CD147, and promoted the cleavage of Caspase-3. The CD147 recovery experiment was further confirmed by the activity changes in the downstream MMPs of CD147. In addition, it was confirmed that the effect of CD147 in promoting TNBC cell proliferation and invasion, inhibiting apoptosis was related to the change in caspase-3 activity.
Conclusion
The downregulation of miR-890 is the potential cause of high CD147 expression in TNBC, which can promote the malignant transformation of TNBC.
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