μM For HepG2 Research Articles

Discovery of novel 4-anilinoquinazoline derivatives as potent inhibitors of epidermal growth factor receptor with antitumor activity

Two new series of new compounds containing a 6-amino-substituted group or 6-acrylamide-substituted group linked to a 4-anilinoquinazoline nucleus have been discovered as potential EGFR inhibitors. These compounds proved efficient effects on antiproliferative activity and EGFR–TK inhibitory activity. Especially, N6-((5-bromothiophen-2-yl)methyl)-N4-(3-chlorophenyl)quinazoline-4,6-diamine (5e), showed the most potent inhibitory activity (IC50=3.11μM for Hep G2, IC50=0.82μM for A549). The EGFR molecular docking model suggested that the new compound is nicely bound to the region of EGFR, and cell morphology by Hoechst stain experiment suggested that these compounds efficiently induced apoptosis of A549 cells.

Abstract 2052: WNT/beta-catenin signaling inhibitors improve the anti-proliferative effect of sorafenib against hepatocellular carcinoma (HCC) cells.

Abstract [Background] Sorafenib, a multikinase inhibitor targeting Raf kinase and vascular endothelial growth factor receptor, is currently the only indicated therapy for patients with advanced hepatocellular carcinoma (HCC). The aberrant activation of WNT/β-catenin signaling pathway, which is associated with the carcinogenetic process of HCC, has been shown to mediate the resistance to various types of anti-cancer therapy. We hypothesized that inhibition of WNT/β-catenin signaling pathway might improve the anti-tumor effect of sorafenib in HCC. [Materials and Methods] Huh7, HepG2, PLC5, and Hep3B HCC cells were treated with sorafenib with or without inhibitors of WNT/β-catenin pathway, and evaluated for viability in vitro. WNT/β-catenin signaling inhibitors included ICG-001 which down-regulates β-catenin/TCF signaling by specifically binding to cyclic AMP response element-binding protein, and XAV939 which targets tankyrases and facilitates degradation of β-catenin. [Results] Sorafenib induced an anti-proliferative effect in HCC cells, with IC50s of 3.5±0.3 μM, 3.7±0.4 μM, 7.7±0.8 μM and 14±0.3 μM for HepG2, Huh7, PLC5, and Hep3B cells, respectively. Upon treated with 10 μM sorafenib for 24 hours, the total cellular amounts of β-catenin were significantly decreased in HepG2 and Huh7 cells, moderately decreased in PLC5 cells, and unchanged in Hep3B cells. In all HCC cells, XAV939 or ICG-001 enhanced the anti-proliferative effect of sorafenib dose-dependently. The median effect analysis showed a synergistic anti-proliferative effect for the combination of ICG-001 plus sorafenib in all HCC cells. [Conclusion] Inhibitors of WNT/β- catenin signaling pathway in combination with sorafenib resulted in an improved anti-tumor effect against HCC in vitro. (The study was supported by the grant NSC 100-2325-B-002-043 from National Science Council of Taiwan) Citation Format: Hsiao-Hui Lin, Wen-Chi Feng, Li-Chun Lu, Yu-Yun Shao, Ann-Lii Cheng, Chih-Hung Hsu. WNT/beta-catenin signaling inhibitors improve the anti-proliferative effect of sorafenib against hepatocellular carcinoma (HCC) cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2052. doi:10.1158/1538-7445.AM2013-2052

HPLC Analysis and Cytotoxic Activity of Vernonia Cinerea

The extracts of five Cambodian medicinal plants (Aganosma marginata, Dracaena cambodiana, Harrisonia perforata, Hymenodictyon excelsum and Vernonia cinerea) were evaluated in vitro for their cytotoxic activity against HT29 colon adenocarcinoma cells and HepG2 hepatoma cells, using the MTT assay. Among these five plants, Vernonia cinerea displayed potent cytotoxicity. One main sesquiterpene lactone, 8alpha-tigloyloxy-hirsutinolide-13-O-acetate was isolated from the whole plant of V. cinerea. This compound was active against both cancer cell lines (IC50 = 3.50 microM for HT29 and IC50 = 4.27 microM for HepG2). To quantify this compound in the plant, an analytical high-performance liquid chromatography (HPLC) method was developed and validated.

Differential effects of arsenic trioxide on chemosensitization in human hepatic tumor and stellate cell lines

BackgroundCrosstalk between malignant hepatocytes and the surrounding peritumoral stroma is a key modulator of hepatocarcinogenesis and therapeutic resistance. To examine the chemotherapy resistance of these two cellular compartments in vitro, we evaluated a well-established hepatic tumor cell line, HepG2, and an adult hepatic stellate cell line, LX2. The aim was to compare the chemosensitization potential of arsenic trioxide (ATO) in combination with sorafenib or fluorouracil (5-FU), in both hepatic tumor cells and stromal cells.MethodsCytotoxicity of ATO, 5-FU, and sorafenib, alone and in combination against HepG2 cells and LX2 cells was measured by an automated high throughput cell-based proliferation assay. Changes in survival and apoptotic signaling pathways were analyzed by flow cytometry and western blot. Gene expression of the 5-FU metabolic enzyme, thymidylate synthase, was analyzed by real time PCR.ResultsBoth HepG2 and LX2 cell lines were susceptible to single agent sorafenib and ATO at 24 hr (ATO IC50: 5.3 μM in LX2; 32.7 μM in HepG2; Sorafenib IC50: 11.8 μM in LX2; 9.9 μM in HepG2). In contrast, 5-FU cytotoxicity required higher concentrations and prolonged (48–72 hr) drug exposure. Concurrent ATO and 5-FU treatment of HepG2 cells was synergistic, leading to increased cytotoxicity due in part to modulation of thymidylate synthase levels by ATO. Concurrent ATO and sorafenib treatment showed a trend towards increased HepG2 cytotoxicity, possibly due to a significant decrease in MAPK activation in comparison to treatment with ATO alone.ConclusionsATO differentially sensitizes hepatic tumor cells and adult hepatic stellate cells to 5-FU and sorafenib. Given the importance of both of these cell types in hepatocarcinogenesis, these data have implications for the rational development of anti-cancer therapy combinations for the treatment of hepatocellular carcinoma (HCC).

Design and synthesis of 4,6-substituted-(diaphenylamino)quinazolines as potent EGFR inhibitors with antitumor activity

A type of novel 4,6-substituted-(diaphenylamino)quinazolines, which designed based on the 4-(phenylamino)quinazoline moiety, have been discovered as potential EGFR inhibitors. These compounds displayed good antiproliferative activity and EGFR-TK inhibitory activity. Especially, 4-((4-(3-bromophenylamino)quinazolin-6-ylamino)methyl)phenol (5b), showed the most potent inhibitory activity (IC50=0.28μM for Hep G2, IC50=0.59μM for A16-F10 and IC50=0.87μM for EGFR) and effectively induces apoptosis in a dose-dependent manner in the Hep G2 cell line. Molecular docking of 5b into EGFR TK active site was also performed. This inhibitor nicely fitting the active site might well explain its excellent inhibitory activity.

Synthesis and antitumor activity of 1,2,4-triazoles having 1,4-benzodioxan fragment as a novel class of potent methionine aminopeptidase type II inhibitors

A series of 1,2,4-triazole derivatives containing 1,4-benzodioxan ( 5a– 5q) have been designed, synthesized, structurally determined, and their biological activities were evaluated as potential MetAP2 inhibitors. All the synthesized compounds were first reported. Among the compounds, compound 5k showed the most potent biological activity against HEPG2 cancer cell line (IC 50 = 0.81 μM for HEPG2 and IC 50 = 0.93 μM for MetAP2), which was comparable to the positive control. Docking simulation by positioning compound 5k into the MetAP2 structure active site was performed to explore the possible binding model. The results of apoptosis and Western-blot assay demonstrated that compound 5k possessed good antitumor activity against HEPG2 cancer cell line. Therefore, compound 5k with potent inhibitory activity in tumor growth inhibition may be a potential antitumor agent against HEPG2 cancer cell.

Synthesis, molecular modeling and biological evaluation of chalcone thiosemicarbazide derivatives as novel anticancer agents

A series of novel chalcone thiosemicarbazide derivatives ( 4a–4x) have been designed, synthesized, structurally determined, and their biological activities were also evaluated as potential EGFR kinase inhibitors. All the synthesized compounds are first reported. Among the compounds, compound 4r showed the most potent biological activity (IC 50 = 0.78 ± 0.05 μM for HepG2 and IC 50 = 0.35 μM for EGFR), which is comparable to the positive controls. Docking simulation was also performed to position compound 4r into the EGFR active site to determine the probable binding model. Antiproliferative assay results demonstrated that some of these compounds possessed good antiproliferative activity against HepG2. Compound 4r with potent inhibitory activity in tumor growth inhibition may be a potential anticancer agent.

Synthesis and biological evaluation of novel Mannich bases of 2-arylimidazo[2,1- b]benzothiazoles as potential anti-cancer agents

A new series of Mannich bases of 2-arylimidazo[2,1- b]benzothiazoles were synthesized and evaluated for their anti-cancer activity. These compounds showed better cytotoxicity activity with IC 50 values ranging from 2.8 to 8.0 μM in HepG2, MCF-7 and HeLa cell lines. Further mechanism aspects responsible for the anti-cancer activity of two promising compounds 3c and 3f in HepG2 cell line were studied. Interestingly, 3c, 3f induced G2/M cell cycle arrest with down regulation of cyclin B and up regulation of Chk2 protein. Moreover, compounds 3c, 3f also showed the characteristic features of apoptosis such as enhancement in the levels of caspase-3. Treatments with compounds led to a decrease in levels of vital cell proliferation proteins such as Jun (C-Jun, JunB), p38 MAPK, p-JNK and PKCα. The compound 3f of the series could be considered as the potential lead for its development as a novel anti-cancer agent.

Antiproliferative and Apoptotic Effects of Tetrandrine on Different Human Hepatoma Cell Lines

Tetrandrine (TET), a bis-benzylisoquinoline alkaloid isolated from the dried root of Hang-Fang-Chi (Stephania tetrandra S. Moore), is well known to possess activities including antioxidant, anti-inflammation, anti-fibrotic and anticancer. It is used clinically to treat hypertension and silicosis. In the present study, the anti-proliferative and apoptotic effects of TET were evaluated on three different hepatoma cell lines, namely Hep G2, PLC/PRF/5 and Hep 3B. Using XTT assay, results showed that the IC50 values of TET were 4.35 microM for Hep G2, 9.44 microM for PLC/PRF/5 and 10.41 microM for Hep 3B cells. The CC50 of TET against BNL-CL.2 mouse normal liver cells was 31.12 microM. Interestingly, TET exhibited a lower IC50 value and better selectivity against Hep G2 and PLC/PRF/5 cells than cisplatin. Microscopic observation study, DNA fragmentation assay and flow cytometric analysis further supported apoptotic effect of TET on both PLC/PRF/5 and Hep 3B cells. The cell cycle of PLC/PRF/5 treated with TET appeared to arrest at G2/M phase in a dose-dependent manner, whereas no effect was noted on the cell cycle of Hep 3B cells. The present study concludes that TET exhibited anti-proliferative effect on Hep G2, PLC/PRF/5 and Hep 3B cells in a dose-dependent manner. TET also possesses a lower IC50 and better SI value than cisplatin against Hep G2 and PLC/PRF/5 cells. The effect of TET on cell cycle progression was found to vary with the type of hepatoma cells, suggesting the genetic make-up of the cells play an important role in the response to drug treatment.

Induction of oxidative stress by endosulfan and protective effect of lipid-soluble antioxidants against endosulfan-induced oxidative damage

The toxic mechanism of endosulfan, a widely used organochlorine pesticide, was investigated in Saccharomyces cerevisiae and human cell lines. A concentration-dependent inhibition of cell growth was observed when S. cerevisiae was exposed to endosulfan, and its cytotoxicity (IC 50) was found to be 49 μM and 86 μM in HepG2 and HeLa human cell lines, respectively. The treatment of S. cerevisiae with endosulfan resulted in oxidative damage, as demonstrated by thiobarbituric acid-reactive substance (TBARS) production, in a dose-dependent manner, and the growth inhibition was recovered by treatment with lipid-soluble antioxidants, such as α-tocopherol or β-carotene, suggesting that endosulfan toxicity may be closely associated with endosulfan-induced reactive oxygen species (ROS) generation. The inhibition of cellular respiration by endosulfan treatment and the recovery of respiration activity by antioxidant treatment confirmed that endosulfan induces oxidative stress and inhibits respiration via ROS generation. These results suggest that unicellular yeast might provide a useful system for elucidating the toxicity of endosulfan.

Synthesis, In Vitro Anti-HIV and Anti-hepatitis B Activities and Pharmacokinetic Properties of Amphiphilic Heterodinucleoside Phosphates Containing ddC and AZT

Amphiphilic heterodinucleoside phosphates containing AZT and ddC as antiviral monomer were synthesized according to the hydrogenphosphonate method and evaluated in vitro against HIV. dT-N4-pamddC was the most active (IC50 = 40 μM, EC50 = 80 nM) and least toxic (TI = 524) dimer and it exhibited also strong antiviral effects against eight AZT-resistant HIV strains. The ddC-containing heterodimers additionally inhibited HBV replication by 50–80% at 50 μM in Hep G2 2.2.15 cells.