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Abnormally high transcription of the glial cell-line derived neurotrophic factor ( gdnf ) gene in glioma cells is related to the hyperacetylation of histone H3 lysine 9 (H3K9) in its promoter region II, but the mechanism remains unclear. There are three consecutive putative binding sites for the transcription factor early growth response protein 1(Egr-1) in promoter region II of the gdnf gene, and Egr-1 participates in gdnf gene transcription activation. Here we show that the acetylation level of H3K9 at Egr-1 binding sites in gdnf gene promoter region II in rat C6 astroglioma cells was significantly higher than that in normal astrocytes, and the binding capacity was also significantly higher. In C6 astroglioma cells, gdnf gene transcription significantly decreased after Egr- 1 knock-down. In addition, the deletion or mutation of the Egr-1 binding site also significantly down-regulated the activity of promoter region II of this gene in vitro. When curcumin decreased the acetylation level of H3K9 at the Egr-1 binding site, the binding of Egr-1 to promoter region II and GDNF mRNA levels significantly decreased. In contrast, trichostatin A treatment significantly increased H3K9 acetylation at the Egr-1 binding site, which significantly increased both the binding of Egr-1 with promoter region II and GDNF mRNA levels. In this context, knocking down Egr- 1 significantly reduced the elevation in gdnf gene transcription. Collectively, our results demonstrate that the hyperacetylation of H3K9 at Egr-1 binding sites in promoter region II of the gdnf gene can up-regulate the binding of Egr-1 to increase gdnf gene transcription in glioma cells. [ABSTRACT FROM AUTHOR]

Highlights: [•] Steroidal dehydroepiandrosterone D-ring-fused heterocycles were synthesized. [•] Anticancer activities in vitro against EC109, EC9706 and MGC-803 cell lines were evaluated. [•] We found several compounds possess good cytotoxicity against EC109 and MGC-803. [•] We summarized the primary structure–activity relationships. [Copyright &y& Elsevier]

Highlights: [•] Steroidal dehydroepiandrosterone[17,16-d]-2-amino thiazole were synthesized in quantitive yields under mild conditions. [•] Aldehydes reacted with steroidal dehydroepiandrosterone[17,16-d]-2-amino thiazole to give the Steroidal imines. [•] Steroidal D-ring fused with heterocycles were obtained with a moderate to good yields. [ABSTRACT FROM AUTHOR]

A series of novel 1,2,3-triazole-pyrimidine hybrids were designed, synthesized and evaluated for their anticancer activity against four selected cancer cell lines (MGC-803, EC-109, MCF-7 and B16-F10). Most of the synthesized compounds exhibited moderate to good activity against all the cancer cell lines selected. Compound 17 showed the most excellent anticancer activity with single-digit micromolar IC 50 values ranging from 1.42 to 6.52 μM. Further mechanism studies revealed that compound 17 could obviously inhibit the proliferation of EC-109 cancer cells by inducing apoptosis and arresting the cell cycle at G2/M phase. [ABSTRACT FROM AUTHOR]

Abstract: A simple and practical method for synthesis of the D-ring modified steroidal dienamides (4a–k) from the steroidal α,α-dicyanoalkene 3 and aldehydes via vinylogous aldol reaction was first reported. By using NaOAc as a base, the desired products were obtained in moderate to good yields in ethanol under mild conditions. All the synthesized steroidal dienamides are new and are currently being evaluated for their biological activities. [Copyright &y& Elsevier]