HL-7702 Cells Research Articles

A facile DNA/RNA nanoflower for sensitive imaging of telomerase RNA in living cells based on “zipper lock-and-key” strategy

The sensitive imaging of telomerase RNA (TR) in living cells is crucial for improved guidance in cancer clinical diagnosis because its expression level is closely related to malignant diseases. The efficient delivery of multiple nucleic acid probes to target cells is critical for nucleic acid-based methods to successfully image low-abundance TR in living cells. While novel nanomaterials enhance delivery efficiency, uncontrolled loading and slow intracellular release remain major challenges for multiple-probe delivery. Here, we designed a facile DNA/RNA nanoflower (NF) to perform the controlled loading of multiple probes and rapid intracellular release based on the “zipper lock-and-key” strategy. First, a long RNA generated by rolling circle transcription acts as both the “smart zipper lock” and the delivery carrier to alternately lock multiple functional DNAs through DNA-RNA base pairing, and the resulting RNA/DNA hybrids self-assemble into packed NFs. The functional DNAs include the fluorescence molecular beacon H1 for TR recognition, H2 for hybrid chain reaction (HCR) and DNA-cholesterol for size control. After NF internalization by the cells, the intracellular RNase H acts as the “key” to specifically open the DNA/RNA NFs by cleaving the RNA in the DNA/RNA hybrid, releasing high amounts of H1 and H2 in a confined space and thereby facilitating the HCR amplification analysis of cytoplasmic TR. With the addition of a DNA-nuclear localization peptide component in the same NF, nuclear TR can also be sensitively detected. Compared with the regular H1/H2 mixture, the DNA/RNA NFs produced a higher-contrast fluorescence signal. This indicated that the proposed strategy allowed the side arms of H1/H2 to be sealed into the RNA sequence-programmed “zipper lock” by controlled loading, avoiding mutual nonspecific H1/H2 hybridization. In addition, due to the fast kinetics of the RNase endonuclease reaction, the loaded H1/H2 was quickly released. Furthermore, the strategy was successfully used to assay the expression levels of TR in HeLa, HepG2 and HL-7702 cells, demonstrating that this approach holds the potential for the sensitive detection of low-abundance biomarkers in living cells.

In vitro screening and toxic mechanism exploring of leading components with potential hepatotoxicity of Herba Epimedii extracts

Herba Epimedii is a famous Chinese edible herb, and due to its potential hepatotoxic effects, the safety associated with this herb has attracted a great deal of attention. In this study, the components of four types of the Herba Epimedii extracts were identified by HPLC-MS/MS. Among these components, 11 components that were present in all four extracts and could be obtained as reference substances were evaluated for their ability of cytotoxicity in HL-7702 and HepG2 cells, resulting in the identification of icarisid I and sagittatoside A as the most relevant with respect to the toxicity of the extracts. The targeted toxicological effects were further investigated using a series of correlated biological indicators to elucidate potentially hepatotoxic mechanisms. The results showed that the extracts and the selected compounds had varying degrees of influence on the leakage of ALT, AST and LDH; the activity of SOD, GSH and MDA; the increase in intercellular ROS; and the decrease in MMP. Among the tested substances, the ethanol extracts exhibited stronger hepatotoxicity, with icarisid I and sagittatoside A correlating with this toxic effect, and the hepatoxic mechanisms of which may be associated with damaged cell structure, increased oxidative stress and induction of apoptosis.

Matrine Exerts Hepatotoxic Effects via the ROS-Dependent Mitochondrial Apoptosis Pathway and Inhibition of Nrf2-Mediated Antioxidant Response.

Matrine, an alkaloid isolated from Sophora flavescens, possesses a wide range of pharmacological properties. However, the use of matrine in clinical practice is limited due to its toxic effects. The present study investigated the roles of mitochondria and reactive oxygen species (ROS) in matrine-induced liver injury. Our results showed that treatment of HL-7702 cells with matrine led to significant and concentration- and time-dependent reductions in their viability, as well as significant and concentration-dependent increases in the number of apoptotic cells and supernatant lactate dehydrogenase (LDH) activity. The treatment led to significant increases in the population of cells in S phase and significant reduction of cell proportion in G0/G1 and G2/M phases. It also significantly and concentration-dependently increased the levels of ROS and malondialdehyde (MDA) but significantly and concentration-dependently reduced superoxide dismutase (SOD) activity, level of reduced glutathione (GSH), and mitochondrial membrane potential (MMP). Matrine treatment significantly and concentration-dependently upregulated the expressions of Bax, p53, p-p53, p21, cyclin E, Fas, cleaved caspase-3, caspase-8, and caspase-9 proteins and downregulated the expressions of Bcl-2, cyclin-dependent kinase 2 (CDK2), and cyclin A. It also significantly promoted the cleavage of poly(ADP-ribose)polymerase (PARP), upregulated Kelch-like ECH-associated protein 1 (Keap1) expression, and downregulated the expressions of cellular total and nuclear Nrf2. Matrine significantly inhibited the expressions of downstream oxidoreductases (Heme oxygenase-1 (HO-1) and NAD(P)H:quinone oxidoreductases 1 (NQO-1)) and enhanced the formation of Keap1/Nrf2 protein complex. These results show that the hepatotoxic effect of matrine is exerted via inhibition of Nrf2 pathway, activation of ROS-mediated mitochondrial apoptosis pathway, and cell cycle arrest at S phase. Pretreatment with N-acetyl cysteine (NAC) partially reversed matrine-induced hepatotoxicity.

Auriculatone Sulfate Effectively Protects Mice Against Acetaminophen-Induced Liver Injury.

Acetaminophen (APAP) overdose is very common worldwide and has been widely recognized as the leading cause of drug-induced liver injury in the Western world. In our previous investigation, auriculatone, a natural product firstly obtained from Aster auriculatus, has demonstrated a potent protective effect against APAP-induced hepatotoxicity in HL-7702 cells. However, the poor water solubility and low bioavailability restrict its application. Auriculatone sulfate (AS) is a sulfated derivative of auriculatone with highly improved water-solubility. Hepatoprotective effects against APAP-induced liver injury (AILI) showed that intragastric pretreatment with AS at 50 mg/kg almost completely prevented mice against APAP-induced increases of serum alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase and ATPase. Histological results showed that AS could protect the liver tissue damage. In addition, AS pretreatment not only significantly retained hepatic malondialdehyde and the activities of glutathione, superoxide dismutase, and glutathione peroxidase at normal levels, but also markedly suppressed the increase of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 levels in mouse liver caused by overdose APAP. Immunohistochemical analysis showed that AS obviously attenuated the expression of CD45 and HNE in liver tissue. Further mechanisms of action investigation showed that inhibition of cytochrome P450 3A11 (CYP 3A11) and CYP2E1 enzymatic activities (but not that of CYP1A2) was responsible for APAP bioactivation. In conclusion, AS showed a hepatoprotective effect against AILI through alleviating oxidative stress and inflammation and inhibiting CYP-mediated APAP bioactivation. It may be an effective hepatoprotective agent for AILI and other forms of human liver disease.

MicroRNA-125a-3p overexpression promotes liver regeneration through targeting proline-rich acidic protein 1

Introduction and objectivesLiver regeneration plays a valuable significance for hepatectomies, and is mainly attributed to hepatocyte proliferation. MicroRNA-125a-3p was reported to be highly associated with liver regeneration process. We studied the underlying mechanism of the functional role of miR-125a-3p in liver regeneration. Materials and methodsThe miR-125a-3p mimics and inhibitor vector were constructed and transfected into primary human liver HL-7702 cells, the transfected cell viability was detected using cell counting kit-8 (CCK-8). Cell cycle distribution was analyzed by flow cytometry. With Targetscan and OUGene prediction, the potential targets of miR-125 were verified by real-time quantitative PCR (qPCR) and luciferase reporter assays in turn. The overexpression vector of proline-rich acidic protein 1 (PRAP1) was constructed and co-transfected with miR-125a-3p mimics into HL-7702 cells, detecting the changes of proliferative capacity and cell cycle distribution. Western blot and qPCR performed to analyze gene expressions. ResultsOverexpressed miR-125a-3p notably increased the hepatocyte viability at 48h, and decreased the number of G1 phase cells (p<0.05). However, miR-125a-3p inhibition suppressed the development of hepatocytes. PRAP1 was the target of miR-125a-3p. After co-transfection with PRAP1 vector, hepatocyte viability was decrease and the G1 phase cell number was increased (p<0.05). More importantly, overexpressed PRAP1 notably decreased the mRNA and protein levels of cyclin D1, cyclin-dependent kinase 2 (CDK2) and cell division cycle 25A (CDC25A). ConclusionThe elevated miR-125a-3p positively correlated with hepatocyte viability and cell cycle progression due to the modulation of PRAP1, and miR-125a-3p may contribute to improving liver regeneration.

HOXA11-AS promotes the migration and invasion of hepatocellular carcinoma cells by inhibiting miR-124 expression by binding to EZH2.

The objective of this study was to examine the function of the long non-coding RNA (lncRNA) HOXA11-AS in hepatocellular carcinoma (HCC). In total, samples from liver tumor and surrounding normal liver tissues were collected from 66 cases of HCC patients. Normal liver cell line HL-7702 and HCC cell lines HepG2, Hep3B, MHCC-97H and BEL7402 were used. Cells were transfected with different small interference RNAs or vectors. Then, transwell assay, qRT-PCR, CHIP, RIP and Western blot experiments were performed. We found that the HOXA11-AS expression level was higher in HCC samples than surrounding normal liver tissues. And the higher expression level of HOXA11-AS in HCC patients indicated a lower 5-year survival rate. Knockdown of HOXA11-AS in HepG2 and Hep3B cells caused impaired cell invasion and migration abilities. Otherwise, upregulation of HOXA11-AS in MHCC-97H and BEL7402 cells displayed higher invasion and migration capabilities. We also demonstrated that HOXA11-AS could inhibit miR-124 expression by binding to EZH2. Furthermore, overexpression of miR-124 or knockdown EZH2 expression could reverse the HOXA11-AS-induced migration and invasion effects in HCC cells. In summary, the high HOXA11-AS expression in HCC patients is associated with the poor outcome. HOXA11-AS could inhibit miR-124 expression by binding to EZH2 and thus promoted the migration and invasion of HCC cells.

Cyanate Induces Oxidative Stress Injury and Abnormal Lipid Metabolism in Liver through Nrf2/HO-1.

Chronic kidney disease (CKD) is problem that has become one of the major issues affecting public health. Extensive clinical data suggests that the prevalence of hyperlipidemia in CKD patients is significantly higher than in the general population. Lipid metabolism disorders can damage the renal parenchyma and promote the occurrence of cardiovascular disease (CVD). Cyanate is a uremic toxin that has attracted widespread attention in recent years. Usually, 0.8% of the molar concentration of urea is converted into cyanate, while myeloperoxidase (MPO) catalyzes the oxidation of thiocyanate to produce cyanate at the site of inflammation during smoking, inflammation, or exposure to environmental pollution. One of the important physiological functions of cyanate is protein carbonylation, a non-enzymatic post-translational protein modification. Carbamylation reactions on proteins are capable of irreversibly changing protein structure and function, resulting in pathologic molecular and cellular responses. In addition, recent studies have shown that cyanate can directly damage vascular tissue by producing large amounts of reactive oxygen species (ROS). Oxidative stress leads to the disorder of liver lipid metabolism, which is also an important mechanism leading to cirrhosis and liver fibrosis. However, the influence of cyanate on liver has remained unclear. In this research, we explored the effects of cyanate on the oxidative stress injury and abnormal lipid metabolism in mice and HL-7702 cells. In results, cyanate induced hyperlipidemia and oxidative stress by influencing the content of total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), superoxide dismutase (SOD), catalase (CAT) in liver. Cyanate inhibited NF-E2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and the phosphorylation of adenosine 5′monophosphate-activated protein kinase (AMPK), activated the mTOR pathway. Oxidative stress on the cells reduced significantly by treating with TBHQ, an antioxidant, which is also an activator of Nrf2. The activity of Nrf2 was rehabilitated and phosphorylation of mTOR decreased. In conclusion, cyanate could induce oxidative stress damage and lipid deposition by inhibiting Nrf2/HO-1 pathway, which was rescued by inhibitor of Nrf2.

MiR-199 inhibits EMT and invasion of hepatoma cells through inhibition of Snail expression.

MiR-199 expression is associated with liver cancer. Bioinformatics analysis revealed that miR-199 has a complementary binding site to the 3'-UTR region of Snail mRNA. This study investigated whether miR-199 plays a role in regulating Snail expression and affecting epithelial-mesenchymal transition (EMT) and invasion of hepatoma cells. The Dual-Luciferase reporter gene assay validated the targeted regulation between miR-199 and Snail. QRT-PCR was used to detect and compare the expression of miR-199 and Snail mRNA in human normal liver HL7702 cells, low metastatic MHCC97L cells, and high metastatic MHCC97H cells. MHCC97H cells were cultured in vitro and divided into two groups: miR-NC group and the miR-199 mimic group followed by the analysis of the expression of Snail, E-cadherin, and N-cadherin, as well as cell invasion ability by transwell assay. There was a targeted regulatory relationship between miR-199 and Snail mRNA. Compared with HL7702 cells, miR-199 expression was significantly decreased, and Snail expression was significantly increased in MHCC97L and MHCC97H cells, with more changes being observed in high metastatic MHCC97H cells. The transfection of miR-199 mimic significantly downregulated the expression of Snail and N-cadherin in MHCC97H cells, increased E-cadherin expression, inhibited the cell's EMT process, and invasion. The decrease of miR-199 expression plays a role in upregulating the expression of Snail and promoting EMT and invasion of hepatocarcinoma cells. The increase of the expression of miR-199 can inhibit the expression of Snail and inhibit the EMT process and invasion ability of hepatoma cells.

Redox-Responsive Disulfide Bond-Bridged mPEG-PBLA Prodrug Micelles for Enhanced Paclitaxel Biosafety and Antitumor Efficacy.

The toxicity and side effects of traditional chemotherapeutic drugs are the main causes of chemotherapy failure. To improve the specificity and selectivity of chemotherapeutic drugs for tumor cells, a novel redox-sensitive polymer prodrug, polyethylene glycol-poly (β-benzyl-L-aspartate) (PEG-PBLA)-SS-paclitaxel (PPSP), was designed and synthesized in this study. The PPSP micelle was manufactured via high-speed dispersion stirring and dialysis. The particle size and zeta potential of this prodrug micelle were 63.77 ± 0.91 nm and −25.8 ± 3.24 mV, respectively. The micelles were uniformly distributed and presented a spherical morphology under a transmission electron microscope. In the tumor physiological environment, the particle size of the PPSP micelles and the release rate of paclitaxel (PTX) were significantly increased compared with those of mPEG-PBLA-CC-PTX (PPCP) micelles, reflecting the excellent redox-sensitive activity of the PPSP micelles. The inhibitory effect of PPSP on HepG2, MCF-7 and HL-7702 cell proliferation was investigated with MTT assays, and the results demonstrated that PPSP is superior to PTX with respect to the inhibition of two tumor cell types at different experimental concentration. Simultaneously PPSP has lower toxicity against HL-7702 cells then PTX and PPCP. Moreover, the blank micelle from mPEG-PBLA showed no obvious toxicity to the two tumor cells at different experimental concentrations. In summary, the redox-sensitive PPSP micelle significantly improved the biosafety and the anti-tumor activity of PTX.

Disodium Guanylate Alleviates Acute Hepatic Injury Induced by Carbon Tetrachloride Via Antioxidative Stress and Antiapoptosis In Vivo and In Vitro.

Hepatic injury is one of the most common digestive system diseases worldwide in clinic. Guanylic acid or guanosine monophosphate (GMP) was an important component of nucleotides, which is mainly in the form of sodium salt (disodium guanylate, GMP-Na2 ). However, its effect on hepatic injury has not yet been investigated. This study is to investigate the protective effects of GMP-Na2 on acute hepatic injury induced by carbon tetrachloride (CCl4 ), and to explore its mechanism. The hepatic injury models of mice and HL-7702 cells were induced by CCl4 . The alanine transaminase (ALT), aspartate aminotransferase (AST), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), total antioxidant capacity (T-AOC) were determined by biochemical method. Hematoxylin-eosin staining were used to determine the morphologicalchanges on liver tissue in mice. The mRNA and protein expressions of caspase-3, Bax, and Bcl-2 were detected by RT-PCR and Western blot analysis. Our results show that GMP-Na2 treatment significantly decreased the activities of ALT and AST, and the levels of MDA as well as increased the levels of SOD, GSH-Px, and T-AOC. Importantly, GMP-Na2 effectively enhanced the antiapoptosis function by upregulating Bcl-2 expression and downregulating caspase-3 and Bax expressions in vivo and in vitro. Moreover, the histopathological changes of liver tissue were obviously improved after GMP-Na2 treatment. These findings suggest that GMP-Na2 has protective effects on hepatic injury, and its mechanisms may be associated with antioxidative stress and antiapoptosis.

Synthesis of P-Stereogenic Diarylphosphinamides as Novel Inhibitors of Melanoma

In this paper, the evaluation on the biological activity of an array of P-stereogenic diaryphosphinamides as novel inhibitors of malignant melanoma was presented. Among 20 derivatives being screened, several of them displayed high inhibition rate up to 90% against the B16 melanoma cells at 100 μg/mL. Moreover, one of them displayed high inhibition activity with IC50 value of 5.8 μg/mL. In contrast, a comparative assay showed that all the compounds were almost inactive or showed only very weak inhibition ability against an array of cell lines including HL7702, Bel7402, HT1080, A549 and McF7 cells. The results suggested that the P-stereogenic diarylphosphinamides may serve as a class of novel lead molecules for further development of new inhibitors for selective inhibition of melanoma.

Complexes of platinum(II/IV) with 2-phenylpyridine derivatives as a new class of promising anti-cancer agents

Four platinum(II/IV) complexes, [PtIV(PPy)2Cl2]·CH3OH (Pt1), [PtIV(TFPy)2Cl2] (Pt2), [PtII(MPy)(H-MPy)Cl] (Pt3), and [PtII(DPPy)(H-DPPy)Cl] (Pt4) with 2-phenylpyridine (H-PPy), 2-(4-trifluoromethylphenyl)pyridine (H-TFPy), 3-methyl-2-phenylpyridine (H-MPy) and 2,5-diphenylpyridine (H-DPPy) were first designed and prepared. Cytotoxic properties of Pt1–Pt4 were evaluated in human tumor HeLa (cervical), MCF-7 (breast), Hep-G2 (hepatoma), T-24 (bladder) cells and HL-7702 nontumorigenic cells by means of the MTT assay. The four Pt complexes Pt1–Pt4 were more selective for HeLa (cervical) cells versus normal HL-7702 cells. Remarkably the most active Pt2 compound, having 2-(4-trifluoromethylphenyl)pyridine (H-TFPy) ligand, showed IC50 values down to 1.01 ± 0.34 μM. Importantly, Pt1 and Pt2 induce apoptosis in T-24 (bladder) cells via ROS-mediated mitochondria dysfunction.

Autophagy in Triptolide-Mediated Cytotoxicity in Hepatic Cells.

Triptolide is a major active ingredient isolated from the traditional Chinese herb Tripterygium wilfordii Hook F. However, its use in clinical practice is limited due to its severe hepatotoxicity. Autophagy, a highly conserved intracellular process, is essential for maintaining cytoplasmic homeostasis. Considering that abnormalities in autophagy are closely associated with drug-mediated hepatotoxicity, we applied human normal liver HL7702 cells to elucidate the roles of autophagy in triptolide-induced hepatotoxicity. Our study revealed that triptolide was cytotoxic to HL7702 cells. It markedly increased autophagosome formation and expression of autophagy-related proteins, namely Beclin1 and microtubule-associated protein 1 light chain 3II, and induced oxidative stress. These proautophagic effects were counteracted by pretreatment with N-acetylcysteine, a reactive oxygen species scavenger. Moreover, the pharmacological suppression of autophagy further exacerbated triptolide-elicited decrease in cell viability, increase in lactate dehydrogenase leakage, and activation of apoptosis proteases (caspase 3 and caspase 9). Our findings suggest that triptolide-induced oxidative stress consequently enhances autophagic activity, and autophagy is a cytoprotective mechanism against triptolide-induced cytotoxicity in HL7702 cells.

Bioactive cembrane-type diterpenoids from the gum-resin of Boswellia carterii

Chemical examination of the gum-resin of Boswellia carterii resulted in the isolation and characterization of eighteen new cembrane-type diterpenoids, named as Boscartins P-AG (1–18) and eight known ones. Their structures were established on the basis of extensive spectroscopic (2D NMR, IR, CD, MS and X-ray) analysis in combination with modified Mosher’s method. All compounds featured unusual 1,12-oxygenated tetrahydrofuran functionalities, and were evaluated for hepatoprotective activity against D-galactosamine-induced HL-7702 cell damage and cytotoxic activity against MCF-7 human breast cancer cell in vitro. Compounds 1, 6–10, 12–13, 16–17 and 21–25 (10 μM) showed some hepatoprotective activity against D-galactosamine-induced HL-7702 cell damage.

Tetracycline uptake by pak choi grown on contaminated soils and its toxicity in human liver cell line HL-7702

Tetracycline (TC) can enter the human body via the soil-vegetable-human food chain; therefore, it is necessary to understand the toxicity of TC to humans through vegetables grown on contaminated soils. The present study combined an enzyme-linked immunosorbent assay method and an HL-7702 cell model and assessed the bioavailability and toxicity of TC from pak choi (Brassica campestris L. ssp. chinensis) grown on TC-contaminated soils. The results showed that the degradation rate of TC in black soil was significantly higher than that in purplish clay, while the results for TC uptake in pak choi were opposite. The bioaccessibility of TC was found to be higher in pak choi grown on purplish clay (5.67–7.59%) than in that grown on black soil (5.22–6.77%). It is suggested that soil properties contribute to the uptake of TC by pak choi. More fertile soil contained lower TC concentrations and thus mediated lower TC toxicity to humans. It may seem comforting that TC concentrations in the edible parts of pak choi are often found to be below safe limits. However, the TC diagnosis method showed that even moderate increases in TC concentrations in pak choi may induce oxidative stress, liver injury, mitochondrial cristae and rough endoplasmic reticulum swelling, and early apoptosis in liver cells HL-7702. The pak choi grown in purplish clay showed higher TC cytotoxicity than that grown in black soil. The TC cytotoxicity of raw pak choi was found to be higher than that of cooked pak choi. These results provide direct evidence of effective ways to prevent TC toxicity in humans.

Intracellular Accumulation as an Indicator of Cytotoxicity to Screen Hepatotoxic Components of Chelidonium majus L. by LC–MS/MS

A novel strategy was developed to identify hepatotoxic compounds in traditional Chinese medicines (TCMs). It is based on the exposure of HL-7702 cells to a TCM extract, followed by the identification and further determination of potential hepatotoxic compounds accumulated in the cells by liquid chromatography–tandem mass spectrometry (LC–MS/MS). As a case study, potential hepatotoxic components in Chelidonium majus L. were screened out. Five alkaloids (sanguinarine, coptisine, chelerythrine, protopine, and chelidonine) were identified by LC–MS/MS within 10 min, and their intracellular concentrations were first simultaneously measured by LC–MS/MS with a run time of 4 min. A cell viability assay was performed to assess the cytotoxicity of each alkaloid. With their higher intracellular concentrations, sanguinarine, coptisine, and chelerythrine were identified as the main hepatotoxic constituents in Ch. majus. The study provides a powerful tool for the fast prediction of cytotoxic components in complex natural mixtures on a high-throughput basis.

Design, Synthesis, and Biological Application of Novel Photoaffinity Probes of Dihydropyridine Derivatives, BAY R3401.

To explore the molecular mechanisms of BAY R3401, four types of novel photoaffinity probes bearing different secondary tags were synthesized. Their potency for glycogenolysis was evaluated in primary human liver HL-7702 cells and HepG2 cells. Probe 2d showed the best activity in primary human liver HL-7702 cells and HepG2 cells, with IC50 values of 4.45 μM and 28.49 μM, respectively. Likewise, probe 5d showed IC50 values of 6.46 μM in primary human liver HL-7702 cells and 15.29 μM in HepG2 cells, respectively. Photoaffinity labeling experiments were also performed and protein bands larger than 170 kDa were specifically tagged by probe 2d. The results suggest that the synthesized probe 2d might be a very promising tool for the isolation of the target proteins of BAY R3401.

Design and Synthesis of Benzopyranopyrimidinyl Phosphonates as Cytotoxic and Antioxidant Agents

Background: A concatenation of bioactive diethyl(2-hydroxyphenylsubstituted) benzopyrano pyrimidinyl phosphonates were synthesized under eco-friendly green conditions in the presence of palladium doped graphitic carbon nitride (Pd@g-C3N4) as catalyst. Methods: he title compounds were evaluated for cytotoxic activity against MCF-7, SW-480, HeLa and HL-7702 cell lines and in-vitro antioxidant activity by DPPH, NO and H2O2 methods. Results: he synthesized compounds manifested robust cytotoxic and antioxidant activities. Conclusion: Some of them showed much higher bioactivity than the standards.

Trichloroethylene-induced downregulation of miR-199b-5p contributes to SET-mediated apoptosis in hepatocytes.

Trichloroethylene (TCE) is a ubiquitous toxicant widespread in our environment. Exposure to TCE can cause severe liver damage. In previous studies, we detected an abnormal elevation of SET (a protein encoded by the SETgene in humans) which was observed in human HL-7702 cells (L-02 hepatocytes) under the treatment of TCE. Moreover, further study indicated that SET acts as an important mediator in TCE-induced hepatocyte apoptosis. The major functions of SET have been elucidated, while the regulatory mechanism responsible for modulation of SET remains unclear. In this study, four major microRNA-related databases were used to screen and identify 6 candidate microRNAs involved in the regulation of SET. Subsequent verification indicated that miR-21 and miR-199b-5p were decreased in TCE-treated L-02 cells, suggesting that miR-21 and miR-199b-5p (miR199b for short) miR199b potentially regulate SET expression. Additionally, the dual-luciferase system revealed that only miR199b could directly bind to untranslated region (3'-UTR) of the SETgene. Modulation of SET by miR199b was verified through overexpression and knockdown of miR199b in L-02 cells. Assessment of apoptosis indicated that elevated miR199b attenuated TCE-induced apoptosis, while reduced miR199b enhanced it. In summary, this study suggests that in cultured hepatocytes, TCE-induced suppression of miR199b drives SET induction, which further mediates the response to TCE.

High in Vitro and in Vivo Tumor-Selective Novel Ruthenium(II) Complexes with 3-(2'-Benzimidazolyl)-7-fluoro-coumarin.

Three novel Ru(II) complexes, namely, (RuCl2[La][DMSO]2)·H2O (Ru1), (RuCl2[Lb][DMSO]2) (Ru2), and (RuCl2[Lc][DMSO]2) (Ru3), which respectively contain 3-(2'-benzimidazolyl)coumarin (La), 3-(2'-benzimidazolyl)-7-fluoro-coumarin (Lb), and 3-(2'-benzimidazolyl)-7-methoxyl-coumarin (Lc), were first designed and characterized. Ru2 showed potent antitumor activity against NCI-H460 cells (IC50 = 0.30 ± 0.02 μM) and high selectivity between NCI-H460 cancer cells and normal HL-7702 cells. Ru2 induced NCI-H460 apoptosis via telomerase inhibition, which involved DNA damage, cell-cycle distribution, and S phase-protein down-regulation. However, Ru1 did not demonstrate such effects in NCI-H460 cells, which is undoubtedly associated with the key regulatory role of the 7-fluoro substituted group in the Lb ligand of Ru2. Ru2 exhibited considerably higher anticancer efficacy (inhibition rate [IR] = 61.3%) compared with cisplatin (IR= 25.5%) in a NCI-H460 xenograft mouse model. Thus, this coumarin Ru(II) compound is a promising Ru2-targeting telomerase anticancer agent.