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Necroptosis is a regulated form of inflammatory cell death driven by activated MLKL. Here, the authors identify a mutation in the brace region that confers constitutive activation, leading to lethal inflammation in homozygous mutant mice and providing insight into human mutations in this region.

MAPK-activated protein kinase 2 (MK2) has diverse roles in cancer. In response to chemotherapy, MK2 inhibition is synthetically lethal to p53-deficiency. While TP53 deletion is rare in glioblastomas, these tumors often carry TP53 mutations. Here, we show that MK2 inhibition strongly attenuated glioblastoma cell proliferation through p53wt stabilization and senescence. The senescence-inducing efficacy of MK2 inhibition was particularly strong when cells were co-treated with the standard-of-care temozolomide. However, MK2 inhibition also increased the stability of p53 mutants and enhanced the proliferation of p53-mutant stem cells. These observations reveal that in response to DNA damaging chemotherapy, targeting MK2 in p53-mutated cells produces a phenotype that is distinct from the p53-deficient phenotype. Thus, MK2 represents a novel drug target in 70% glioblastomas harboring intact TP53 gene. However, targeting MK2 in tumors with TP53 mutations may accelerate disease progression. These findings are highly relevant since TP53 mutations occur in over 50% of all cancers.

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is known as a "death ligand"-a member of the TNF superfamily that binds to receptors bearing death domains. As well as causing apoptosis of certain types of tumor cells, TRAIL can activate both NF-kappaB and JNK signalling pathways. To determine the role of TGF-beta-Activated Kinase-1 (TAK1) in TRAIL signalling, we analyzed the effects of adding TRAIL to mouse embryonic fibroblasts (MEFs) derived from TAK1 conditional knockout mice. TAK1-/- MEFs were significantly more sensitive to killing by TRAIL than wild-type MEFs, and failed to activate NF-kappaB or JNK. Overexpression of IKK2-EE, a constitutive activator of NF-kappaB, protected TAK1-/- MEFs against TRAIL killing, suggesting that TAK1 activation of NF-kappaB is critical for the viability of cells treated with TRAIL. Consistent with this model, TRAIL failed to induce the survival genes cIAP2 and cFlipL in the absence of TAK1, whereas activation of NF-kappaB by IKK2-EE restored the levels of both proteins. Moreover, ectopic expression of cFlipL, but not cIAP2, in TAK1-/- MEFs strongly inhibited TRAIL-induced cell death. These results indicate that cells that survive TRAIL treatment may do so by activation of a TAK1-NF-kappaB pathway that drives expression of cFlipL, and suggest that TAK1 may be a good target for overcoming TRAIL resistance.

Using combined chromatographic methods, two asterosaponins (compounds1and2), including a new compound novaeguinoside E (compound1), and six glycosylated polyhydroxysteroids (compounds3–8) were isolated from a methanol extract of the starfishCulcita novaeguineae. Their structures were determined on the basis of spectroscopic data (1H and13C NMR, HSQC, HMBC,1H–1H COSY, ROESY, and HRESI-MS) and by comparison with the literature values. The new compound1represents the third example of asterosaponins containing the 5α-cholesta-9(1l)-en-3β,6α,20,22-tetraol aglycone. Among isolated compounds,4–7exhibited moderate to weak cytotoxic activities against five human cancer cell lines such as Hep-G2 (hepatoma), KB (epidermoid carcinoma), LNCaP (prostate cancer), MCF7 (breast cancer), and SK-Mel2 (melanoma). [ABSTRACT FROM AUTHOR]

An abstract of the article "Structures and Absolute Stereochemistry of Guaiane Sesquiterpenoids from the Gorgonian Menella woodin" by C. Diep and colleagues is presented.

The article presents a study which explores that Tankyrase-mediated ADP-ribosylation, a regulator of Tumor necrosis factor (TNF)-induced death . It mentions that findings of the study suggests that disruption of ADP-ribosylation during an infection can prime a cell to retaliate with an inflammatory cell death.

Two new guaiane derivatives (1 and 2) along with six known sesquiterpenoids (3-8) were isolated from the gorgonian Menella woodin. Their structures -were elucidated by ID and 2D NMR and HRESIMS data as well as by comparison of their spectra with those in the literature. Relative configurations of asymmetric centers in 1 and 2 were suggested on the basis of NOESY and ID NOE correlations, absolute stereochemistry of these compounds was proposed in result of comparison of calculated (for both enatiomers) and experimental ECD. Some suggestions were made regarding a biosynthesis of guaiane sesquiterpenoids in this species. All the compounds were firstly isolated from M woodin.

Nine secondary metabolites, including a new cycloartane glucoside, rhizostyloside (1), were isolated from a methanol extract of Rhizophora stylosa leaves through several chromatographic experiments. The structures of the compounds were determined on the basis of NMR spectroscopic (1H and 13C NMR, HSQC, HMBC, 1H-1H COSY, NOESY) and HR-ESI-MS data and by comparison with literature values. Compound 1 exhibited significant cytotoxicity against three human cancer cell lines: KB (epidermoid carcinoma), LU-1 (lung adenocarcinoma), and SK-Mel-2 (melanoma). In addition, 1 strongly activated caspase-3/7 in LU-1 cells.

Phytochemical study of the methanol extract of Artocarpus altilis resulted in the isolation of a new prenylated aurone, artocarpaurone (1), together with eight known compounds including two prenylated chalcones (2 and 3), three prenylated flavanones (4-6), and three triterpenes (7-9). The structure of 1 was elucidated as 6-hydroxy-2-[8-hydroxy-2-methyl-2-(4-methyl-3-pentenyl)-2H-1-benzopyran-5-ylmethylene]-3(2H)-benzofuranone by spectroscopic methods including 1D and 2D NMR spectra and FT-ICR-MS. Compound 1 showed moderate nitric oxide radical scavenging activity, whereas 2 and 3 had moderate 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect, compared with the positive control (+)-catechin.