Novel 1,5-diphenyl-6-substituted 1H-pyrazolo[3,4-d]pyrimidin-4(5H)-ones induced apoptosis in RKO colon cancer cells

Novel 1,5-diphenyl-6-substituted-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-ones were synthesized and characterized. All compounds were screened for their anti-proliferative activities in five different cancer cell lines. The results showed that compounds 7a and 7b comprising aminoguanidino or guanidino moiety at position 6 inhibited proliferation of RKO colon cancer cells with IC50 of 8 and 4 μM, respectively. Compounds 7a and 7b induced apoptosis in RKO cells, which was confirmed by TUNEL and annexin V-FITC assays. Flow cytometric analysis indicated that compounds 7a and 7b arrested RKO cells in the G1 phase and the most active compound 7b increased levels of p53, p21, Bax, ERK1/2 and reduced levels of Bcl2 and Akt. Compound 7b also activates release of cytochrome c, which is consistent with activation of caspase-9. Additionally, compound 7b increased caspase-3 activity and cleaved PARP-1 in RKO cells. Collectively, these findings could establish a molecular basis for the development of new anti-cancer agents

Novel thiosemicarbazides induced apoptosis in human MCF-7 breast cancer cells via JNK signaling

<div><p></p><p>In this study, novel thiosemicarbazides and 1,3,4-oxadiazoles were synthesized and evaluated for their anticancer effects on human MCF-7 breast cancer cell lines. Among the synthesized derivatives studied, compound 2-(3-(4-chlorophenyl)-3-hydroxybutanoyl)-N-phenylhydrazinecarbothioamide <b>4c</b> showed the highest cytotoxicity against MCF-7 breast cancer cells as it reduced cell viability to approximately 15% compared to approximately 25% in normal breast epithelial cells. Therefore, we focused on <b>4c</b> for further investigations. Our data showed that <b>4c</b> induced apoptosis in MCF-7 cells which was further confirmed by TUNEL assay. Western blotting analysis showed that compound <b>4c</b> up-regulated the pro-survival proteins Bax, Bad and ERK1/2, while it down-regulated anti-apoptotic proteins Bcl-2, Akt and STAT-3. Additionally, <b>4c</b> induced phosphorylation of SAPK/JNK in MCF-7 cells. Pretreatment of MCF-7 cells with 10 µM of JNK inhibitor significantly reduced <b>4c</b>-induced apoptosis. Molecular docking results suggested that compound <b>4c</b> showed a binding pattern close to the pattern observed in the structure of the lead fragment bound to JNK1. Collectively, the data of current study suggested that the thiosemicarbazide <b>4c</b> might trigger apoptosis in human MCF-7 cells by targeting JNK signaling.</p></div

Design and Synthesis of Novel Thioethers Derived from 1,5-Diphenyl-6- thioxo-6,7-dihydro-1H-pyrazolo[3,4-d]pyrimidin-4(5H)-ones as Antiangiogenic Agents

Background: In attempts to discover new antiangiogenic entities, a novel series of thioethers derived from 6-thioxo-6,7-dihydro-1H-pyrazolo[3,4-d]pyrimidine-4(5H)ones was considered and designed. Methods: Virtual screening was carried out through docking of the compounds into the vascular endothelial growth factor and matrix metalloproteinase-9 binding sites. Molecular docking studies were performed using Lamarckian Genetic Algorithm. Compounds possessing lowest ligand-protein pairwise interaction energies were synthesized and screened for their antiproliferative activities against five cancer cell lines namely MHCC97H (liver), MDA-MB 231 (Breast), Colo205 (Co-lon), A549 (lung), A498 (kidney) and IC50 values were determined for the most potent compounds. Additionally, they were tested for their antiangiogenic activities by testing their ability to inhibit Human Umbilical Vein Endothelial Cell (HUVEC), cord formation and migration in response to chemoattractant. Results: Three compounds 2a, 2b and 5b showed significant antiangiogenic activities. The allyl thioether 2b was the most active with chemotaxis activity data nearly comparable to that of the positive control, TNP-470. Additionally, 2a, 2b and 5b, contrary to TNP-470, interfered with the migration of HUVECs in response to vascular endothelial growth factor rather than endothelial cells proliferation or cord formation. Compounds 2a, 2b and 5b were also investigated for their inhibitory effects on MMPs to investigate the relationship between their angiogenic activity and MMPs. Results revealed that compound 2b was the most effective MMP-9 inhibitor in this series. Additionally, compound 2b reduced the expression levels of VEGF and pERK1/2. Conclusion: Our results suggest that compound 2b is considered as a promising antiangiogenic agent by targeting VEGF and MMP-9. 2019 Bentham Science Publishers.Scopu