Synthesis and antibacterial activity of new sulfonamide isoxazolo[5,4-b]pyridine derivatives

A series of novel sulfonamide isoxazolo[5,4-b]pyridines were synthesized. The substrates for their synthesis were 3-aminoisoxazolo[5,4-b]pyridine and selected aryl sulfonic chlorides, chlorosulfonic acid and selected amines. Reactions were carried out using the classical and microwave methods. Selected compounds were tested towards antibacterial and antiproliferative activity. The structure of the obtained new derivatives was determined by elemental analysis and acquired IR and 1H NMR spectra. Among the tested compounds: N-isoxazolo[5,4-b]pyridine-3-yl-benzenesulfonamide (2) and N-isoxazolo[5,4-b]pyridine-3-yl-4-methylbenzene-sulfonamide (5) showed antimicrobial activity towards Pseudomonas aeruginosa (ATCC 27853) and Escherichia coli (ATCC 25922) at doses: 125, 250 and 500 μg. Both compounds showed a 50% inhibition of proliferation of breast carcinoma cell line MCF7 at concentrations of 152.56 μg/mL and 160 161.08 Ïg/mL, respectively

Downregulation of MALAT1 in triple-negative breast cancer cells

Background: MALAT1 is one of the most abundant nuclear long non-coding RNAs, which has been found to be elevated in various types of cancers. However, conflicting reports on MALAT1 in breast cancer cell lines challenge understanding of MALAT1's involvement in breast cancer progression. Aim: Measurement of normalized relative quantity (NRQ) of MALAT1 transcripts in cell lines representing triple-negative breast cancer (TNBC) and luminal breast cancer. Materials and methods: The studies were performed using cell lines representing luminal breast cancer (T47D, MCF-7), TNBC (MDA-MB-468, CAL-51, MDA-MB-231), and MCF-10A cell line of normal breast epithelial cells. Total RNA was isolated from six independent cell cultures of each line, treated with DNase I, and used to synthesize complementary DNA, which was used in quantitative real-time PCR (qPCR) assays. Four MALAT1 fragments and reference genes CCSER2, ANKRD17, PUM1, GAPDH were amplified. Results: Geometric means of the NRQ of MALAT1 in breast cancer cell lines had the shortest 95% confidence intervals when CCSER2 was used for normalization. MALAT1 major transcript levels thus estimated in TNBC cell lines were found to be statistically significantly reduced compared to levels in both MCF-10A cells and luminal breast cancer cell lines, while MALAT1 minority splice variants were found to be increased in almost all breast cancer cell lines. Conclusion: CCSER2-normalized qPCR results indicate MALAT1 downregulation in cell lines representing the more aggressive breast cancer subtype compared to both the normal breast epithelial cell line and the estrogen receptor-positive breast cancer cell lines

Sp1 mediates phorbol ester (PMA)-induced expression of membrane-bound guanylyl cyclase GC-A in human monocytic THP-1 cells

Cyclic guanosine monophosphate (cGMP) is synthesized by two types of enzymes: particulate (membrane-bound) guanylyl cyclases (pGCs) and soluble (cytosolic) guanylyl cyclases (sGCs). sGCs are primarily activated by binding of nitric oxide to their prosthetic heme group while pGCs are activated by binding of peptide ligands to their extracellular domains. One of them, pGC type A (GC-A) is activated by atrial and brain natriuretic peptides (ANP and BNP, respectively). Human monocytes isolated from peripheral blood mononuclear cells have been found to display sGC expression without concomitant expression of GC-A. However, GC-A activity appears in monocytes under certain conditions but a molecular mechanism of GC-A expression is still poorly understood. In this report we show that phorbol ester (PMA) induces transcription of a gene encoding GC-A in human monocytic THP-1 cells. Moreover, we find that PMA-treated THP-1 cells raise cGMP content following treatment with ANP. Studies using pharmacological inhibitors of protein kinases suggest involvement of protein kinase C (PKC), mitogen extracellular kinases (MEK1/2), and extracellular signal-regulated kinases (ERK1/2) in PMA-induced expression of the GC-A encoding gene in THP-1 cells. Finally, we show that PMA stimulates binding of Sp1 transcription factor to GC-rich DNA sequences and mithramycin A (a selective Sp1 inhibitor) inhibits expression of the GC-A mRNA in PMA-treated THP-1 cells. Taken together, our findings suggest that the PMA-stimulated PKC and MEK/ERK signaling pathways induce Sp1-mediated transcription of the GC-A encoding gene in human monocytic THP-1 cells

Comparability of Raman Spectroscopic Configurations: A Large Scale Cross-Laboratory Study

International audienceThe variable configuration of Raman spectroscopic platforms is one of the major obstacles in establishing Raman spectroscopy as a valuable physicochemical method within real-world scenarios such as clinical diagnostics. For such real world applications like diagnostic classification, the models should ideally be usable to predict data from different setups. Whether it is done by training a rugged model with data from many setups or by a primary-replica strategy where models are developed on a ‘primary’ setup and the test data are generated on ‘replicate’ setups, this is only possible if the Raman spectra from different setups are consistent, reproducible, and comparable. However, Raman spectra can be highly sensitive to the measurement conditions, and they change from setup to setup even if the same samples are measured. Although increasingly recognized as an issue, the dependence of the Raman spectra on the instrumental configuration is far from being fully understood and great effort is needed to address the resulting spectral variations and to correct for them. To make the severity of the situation clear, we present a round robin experiment investigating the comparability of 35 Raman spectroscopic devices with different configurations in 15 institutes within seven European countries from the COST (European Cooperation in Science and Technology) action Raman4clinics. The experiment was developed in a fashion that allows various instrumental configurations ranging from highly confocal setups to fibre-optic based systems with different excitation wavelengths. We illustrate the spectral variations caused by the instrumental configurations from the perspectives of peak shifts, intensity variations, peak widths, and noise levels. We conclude this contribution with recommendations that may help to improve the inter-laboratory studies