Selective Cytotoxic Activity Research Articles

Aglycone flavonoid brachydin A shows selective cytotoxicity and antitumoral activity in human metastatic prostate (DU145) cancer cells.

In prostate cancer, flavonoids possess a wide variety of anticancer effects, focused on the antioxidant/pro-oxidant activity, inactivation of the androgen receptor, cell cycle arrest, apoptosis induction, metastasis inhibition, among others. This current research investigated the antitumoral in vitro activity of Brachydin A (BrA), a dimeric flavonoid isolated from Fridericia platyphylla, in human castration-resistant prostate cancer DU145. It was compared BrA selective effects in tumor prostate DU145 cells with non-tumor prostate epithelial PNT2 cells. Cell viability experiments (resazurin, neutral red, MTT, and LDH release assays) showed that BrA was sevenfold more cytotoxic to tumor cells than non-tumor prostate cells, with IC50 values of 77.7 µM and 10.7 µM for PNT2 and DU145 cells, respectively. Furthermore, BrA induced necrosis and apoptosis (triple fluorescence staining assay) without interfering with oxidative stress (CM-H2DCFDA) in DU145 cells. Also, BrA (15.36 µM) reduced cell proliferation on clonogenic assay (DU145 cells) but no change in cell number and protein content was observed when cell growth curve assay was used. Wound healing and transwell assays were used for checking the effects of BrA on cell migration and invasion, and BrA impaired these processes in PNT2 (wound healing) and DU145 cells (transwell). Our results inspire further studies to test BrA as a novel chemotherapeutic drug and to evaluate its effects on drug-resistant metastatic cancer cells.

Two pairs of epimers and three undescribed diterpenoids from Pseudocaryopteris paniculata

A phytochemical investigation on the petroleum ether partition of the whole plant of Pseudocaryopteris paniculata, yield seven new compounds: one phytanes diterpenoid (2Z,6E,10E) 14-keto-2,6,10-trimethyl pentadeca-2,6,10-trien-1-carboxylic acid (1), five clerodane diterpenoids: paniculatins A-E (2, 3a/3b, 4a/4b), one abietane diterpenoid: ent-uncinatone (5), together with 12 known compounds. Their structures were elucidated on the basis of 1D and 2D Nuclear Magnetic Resonance （NMR_, Infrared Radiation (IR), and mass spectroscopic data. Compound 2, 5, and 11 showed weak selective cytotoxic activity of 11 human cancer cell lines.

Synthesis of 1,4-dihydropyrano[2,3-c]pyrazole derivatives and exploring molecular and cytotoxic properties based on DFT and molecular docking studies

• Dicyclic 1,4-dihydropyran[2,3- c ]pyrazole-5-carbonitrile derivatives were synthesized as potential anticancer agents. • The cytotoxic activity was tested against PC-3, SKOV-3, HeLa and A549 cell lines. • The frontier molecular orbitals, electron affinity, ionization potential and molecular electrostatic potential (MEP) were studied. • The molecular docking was accomplished onto thymidylate synthase (TS) protein was discussed. One-pot multicomponent reaction of ethyl 3-oxobutanoate or ethyl 3-oxo-3-phenylpropanoate, hydrazine hydrate, malononitrile, various aldehydes in ethanolic piperidine solution under Microwave irradiation gave 6-amino-4-aryl/hetaryl-3-methyl/pheny-1,4-dihydropyran[2,3- c ]pyrazole-5-carbonitriles. The structures of these compounds were established on the basis of IR, 1 H NMR, 13 C NMR, 13 C NMR-APT, MS data and elemental analysis. Furthermore, the cytotoxic activity properties were evaluated against the human cancer cell lines PC-3, SKOV-3, HeLa and A549 in comparison to the positive controls Vinblastine and Doxorubicin, employing the viability assay. The obtained results confirmed that some of the tested molecules revealed strong and selective cytotoxic activities against the four cancer cell lines. Herein, frontier molecular orbitals (FMO), electron affinity (EA), ionization potential (IP) and molecular electrostatic potential (MEP) was carried out to understand the active sites and biological active nature of pyrano[2,3- c ]pyrazole synthesized compounds. A systematic study was performed then frontier molecular orbitals energies, active sites and molecular descriptors were compared with reference drug. The molecular docking was accomplished onto thymidylate synthase (TS) protein. The compounds with highest efficiency exhibited promising binding interactions and binding affinities into active site.

Targeting Autophagy Triggers Apoptosis and Complements the Action of Venetoclax in Chronic Lymphocytic Leukemia Cells.

Simple SummaryVenetoclax is an antagonist of the antiapoptotic protein Bcl-2, and is currently approved for treatment of chronic lymphocytic leukemia (CLL). Recently, clinical use has shown that patients develop resistance to venetoclax. Therefore, the demand for novel targets for treatment of CLL remains high. One such target is autophagy, an evolutionarily old system for degradation of long-lived proteins and organelles that recovers the energy for normal cellular functions. Here, the antileukemic potential of different autophagy inhibitors was evaluated in patient-derived CLL cells. Among these, inhibitors of the AMPK/ULK1 pathway and late-stage autophagy were the most potent, with selective cytotoxic activities seen. They also show activity against CLL cells with unfavorable genetic characteristics. These inhibitors complement the cytotoxic action of venetoclax. In conclusion, targeting autophagy shows potential as a novel approach for treatment of patients with CLL.Continuous treatment of patients with chronic lymphocytic leukemia (CLL) with venetoclax, an antagonist of the anti-apoptotic protein Bcl-2, can result in resistance, which highlights the need for novel targets to trigger cell death in CLL. Venetoclax also induces autophagy by perturbing the Bcl-2/Beclin-1 complex, so autophagy might represent a target in CLL. Diverse autophagy inhibitors were assessed for cytotoxic activities against patient-derived CLL cells. The AMPK inhibitor dorsomorphin, the ULK1/2 inhibitor MRT68921, and the autophagosome–lysosome fusion inhibitor chloroquine demonstrated concentration-dependent and time-dependent cytotoxicity against CLL cells, even in those from hard-to-treat patients who carried del(11q) and del(17p). Dorsomorphin and MRT68921 but not chloroquine triggered caspase-dependent cell death. According to the metabolic activities of CLL cells and PBMCs following treatments with 10 µM dorsomorphin (13% vs. 84%), 10 µM MRT68921 (7% vs. 78%), and 25 µM chloroquine (41% vs. 107%), these autophagy inhibitors are selective toward CLL cells. In these CLL cells, venetoclax induced autophagy, and addition of dorsomorphin, MRT68921, or chloroquine showed potent synergistic cytotoxicities. Additionally, MRT68921 alone induced G2 arrest, but when combined with venetoclax, it triggered caspase-dependent cytotoxicity. These data provide the rationale to target autophagy and for autophagy inhibitors as potential treatments for patients with CLL.

Cytotoxic Minor Piericidin Derivatives from the Actinomycete Strain Streptomycespsammoticus SCSIO NS126.

The mangrove-sediment-derived actinomycete strain Streptomyces psammoticus SCSIO NS126 was found to have productive piericidin metabolites featuring anti-renal cell carcinoma activities. In this study, in order to explore more diverse piericidin derivatives, and therefore to discover superior anti-tumor lead compounds, the NS126 strain was further fermented at a 300-L scale under optimized fermentation conditions. As a result, eight new minor piericidin derivatives (piericidins L-R (1–7) and 11-demethyl-glucopiericidin A (8)) were obtained, along with glucopiericidin B (9). The new structures including absolute configurations were determined by spectroscopic methods coupled with experimental and calculated electronic circular dichroism. We also proposed plausible biosynthetic pathways for these unusual post-modified piericidins. Compounds 1 and 6 showed selective cytotoxic activities against OS-RC-2 cells, and 2–5 exhibited potent cytotoxicity against HL-60 cells, with IC50 values lower than 0.1 μM. The new piericidin glycoside 8 was cytotoxic against ACHN, HL-60 and K562, with IC50 values of 2.3, 1.3 and 5.5 μM, respectively. The ability to arrest the cell cycle and cell apoptosis effects induced by 1 and 6 in OS-RC-2 cells, 2 in HL-60 cells, and 8 in ACHN cells were then further investigated. This study enriched the structural diversity of piericidin derivatives and confirmed that piericidins deserve further investigations as promising anti-tumor agents.

New coumarin glycosides from endemic Prangos heyniae H. Duman & M.F. Watson

Two new coumarin glycosides, named 7-methoxy isoarnottinin 4'-O-β-ᴅ-glucopyranoside and 7-methoxy isoarnottinin 4'-O-rutinoside (1 and 2) along with six known compounds (3-8) were isolated from the roots of Prangos heyniae, an endemic plant of Turkey. 1-methylethyl 6-O-D-apio-β-ᴅ-furanosyl-β-ᴅ-glucopyranoside (7) and cnidioside A (8) have been obtained from the genus Prangos for the first time. Structures of isolated compounds were established using spectroscopic methods (1 D and 2 D NMR, HR-MS, UV and IR). Moreover, all extracts and isolated compounds were evaluated for their cytotoxic activity against NIH/3T3, HK-2, A-549, MCF-7, PC-3 and SH-SY5Y cell lines by WST-1 method. One of the new coumarin glycosides, 7-methoxy isoarnottinin 4'-O-β-ᴅ-glucopyranoside (1) exhibited selective cytotoxic activity against SH-SY5Y cells with IC50 value of 31.41 ± 1.04 μM.

Ruthenium Complexes as Promising Candidates against Lung Cancer.

Lung cancer is one of the most common malignancies with the highest mortality rate and the second-highest incidence rate after breast cancer, posing a serious threat to human health. The accidental discovery of the antitumor properties of cisplatin in the early 1960s aroused a growing interest in metal-based compounds for cancer treatment. However, the clinical application of cisplatin is limited by serious side effects and drug resistance. Therefore, other transition metal complexes have been developed for the treatment of different malignant cancers. Among them, Ru(II/III)-based complexes have emerged as promising anticancer drug candidates due to their potential anticancer properties and selective cytotoxic activity. In this review, we summarized the latest developments of Ru(II/III) complexes against lung cancer, focusing mainly on the mechanisms of their biological activities, including induction of apoptosis, necroptosis, autophagy, cell cycle arrest, inhibition of cell proliferation, and invasion and metastasis of lung cancer cells.

Carbohydrate-Based NK1R Antagonists with Broad-Spectrum Anticancer Activity.

NK1R antagonists, investigated for the treatment of several pathologies, have shown encouraging results in the treatment of several cancers. In the present study, we report on the synthesis of carbohydrate-based NK1R antagonists and their evaluation as anticancer agents against a wide range of cancer cells. All of the prepared compounds, derived from either d-galactose or l-arabinose, have shown high affinity and NK1R antagonistic activity with a broad-spectrum anticancer activity and an important selectivity, comparable to Cisplatin. This strategy has allowed us to identify the galactosyl derivative 14α, as an interesting hit exhibiting significant NK1R antagonist effect (kinact 0.209 ± 0.103 μM) and high binding affinity for NK1R (IC50 = 50.4 nM, Ki = 22.4 nM by measuring the displacement of [125I] SP from NK1R). Interestingly, this galactosyl derivative has shown marked selective cytotoxic activity against 12 different types of cancer cell lines.

Assessment of Dietary Bioactive Phenolic Compounds and Agricultural Sustainability of an African Leafy Vegetable Corchorus olitorius L.

Corchorus olitorius L. is an African leafy vegetable of high nutritional interest. To assess its agricultural suitability to sustainable cultivation conditions and its potential benefits for human nutrition, its phytochemical content in response to conservation agriculture practices [i.e., no-tillage (NT) and cover crop maintenance] and low water regime were evaluated and compared with response under conventional agriculture management. Hydric stress and NT did not affect the content of antioxidant metabolites, compared to conventional agricultural practices. In both conditions, leaves were found to be a great source of phenolic compounds. The effect of these phenolic fractions was assessed on two colon cell phenotypes to evaluate putative nutraceutical properties. Polyphenol-enriched extracts (PEEs) displayed selective cytotoxic activities against tumor Caco-2 cells but not on the healthy CCD841 line. PEEs were able to trigger oxidative stress and to inhibit the activity of glutathione-independent antioxidant enzymes on Caco-2 cells. C. olitorius showed to be a promising crop for improving both agricultural sustainability and health benefits due to the great amount of antioxidant compounds in leaves, whose occurrence is not altered by stressful farming conditions. Given its high adaptability, the cultivation of this crop is therefore recommendable also in the Mediterranean Basin.

Ethiopian Medicinal Plants Traditionally Used for the Treatment of Cancer; Part 3: Selective Cytotoxic Activity of 22 Plants against Human Cancer Cell Lines.

Medicinal plants have been traditionally used to treat cancer in Ethiopia. However, very few studies have reported the in vitro anticancer activities of medicinal plants that are collected from different agro-ecological zones of Ethiopia. Hence, the main aim of this study was to screen the cytotoxic activities of 80% methanol extracts of 22 plants against human peripheral blood mononuclear cells (PBMCs), as well as human breast (MCF-7), lung (A427), bladder (RT-4), and cervical (SiSo) cancer cell lines. Active extracts were further screened against human large cell lung carcinoma (LCLC-103H), pancreatic cancer (DAN-G), ovarian cancer (A2780), and squamous cell carcinoma of the esophagus (KYSE-70) by using the crystal violet cell proliferation assay, while the vitality of the acute myeloid leukemia (HL-60) and histiocytic lymphoma (U-937) cell lines was monitored in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) microtiter assay. Euphorbia schimperiana, Acokanthera schimperi, Kniphofia foliosa, and Kalanchoe petitiana exhibited potent antiproliferative activity against A427, RT-4, MCF-7, and SiSo cell lines, with IC50 values ranging from 1.85 ± 0.44 to 17.8 ± 2.31 µg/mL. Furthermore, these four extracts also showed potent antiproliferative activities against LCLC-103H, DAN-G, A2780, KYSE-70, HL-60, and U-937 cell lines, with IC50 values ranging from 0.086 to 27.06 ± 10.8 µg/mL. Hence, further studies focusing on bio-assay-guided isolation and structural elucidation of active cytotoxic compounds from these plants are warranted.

Cytotoxic Sesquiterpene Coumarins from the Roots of Heptaptera cilicica

Preliminary 2-day cancer cell screening assays indicated that the dichloromethane extract of the roots of Heptaptera cilicica showed relatively strong cytotoxic activity. Eleven sesquiterpene coumarin ethers with potent and selective cytotoxic activities were isolated from the dichloromethane extract of the roots of H. cilicica. Furthermore, revised spectroscopic data for 14′-acetoxybadrakemone (4) and complete NMR spectroscopic assignments for colladonin (6) and colladin (7) are reported.

Synthesis of propargylamine mycophenolate analogues and their selective cytotoxic activity towards neuroblastoma SH-SY5Y cell line

Twenty six propargylamine mycophenolate analogues were designed and synthesized from mycophenolic acid 1 employing a key step A3-coupling reaction. Their cytotoxic activity was examined against six cancer cell lines. Compounds 6a, 6j, 6t, 6u, and 6z exhibited selective cytotoxicity towards neuroblastoma (SH-SY5Y) cancer cells and were less toxic to normal cells in comparison to the lead compound, MPA 1 and a standard drug, ellipticine. Molecular docking results suggested that compound 6a is fit well in the key amino acid of three proteins (CDK9, EGFR, and VEGFR-2) as targets in cancer therapy. The propargylamine mycophenolate scaffold might be a valuable starting point for development of new neuroblastoma anticancer drugs.

Green Synthesis of Zinc Oxide Nanoparticles (ZnO NPs) using Aqueous Extract of Tagetes Erecta flower and Evaluation of its Antioxidant, Antimicrobial, and Cytotoxic activities on HeLa cell line.

Background:The Zinc oxide Nanoparticles (ZnO NPs) were synthesized successfully by using Tagetes erecta flower aqueous extract and evaluated for their antioxidant potential, antimicrobial and cytotoxic potential.Methods:Phytochemical screening of aqueous crude extract and synthesized ZnO NPs of Tagetes erecta flower revealed the presence of alkaloids, flavonoids, carbohydrates, amino acids, tannins, proteins, etc. The characterization was done by various spectral analyses. In vitro antioxidant activities of synthesized ZnO NPs were found to possess concentration-dependent free radical scavenging activity was carried on different free radicals i.e. DPPH and ABTS. Antimicrobial activity of synthesized ZnO NPs was performed by agar well diffusion method and compared with control ampicillin, while cytotoxic effects were determined by MTT assay against human cervical cancer cell line.Results:UV-Visible spectra were conducted to confirm the synthesis of ZnO NPs and peak obtained at 364.15nm. X-ray analysis confirmed the crystalline nature of the nanoparticles and the average size of the nanoparticles was 30-50nm and was spherical shape analyzed by SEM. The synthesized ZnO NPs showed antimicrobial activity against all tested microorganisms and a maximum inhibition zone was found against E. coli in gram-negative and S. aureus in gram-positive bacteria. Synthesized ZnO NPs were showed 50% cell viability at 26.53μg/ml against the HeLa cancer cell line.Conclusion:The conclusion of this study suggests both the aqueous crude extract of Tagetes erecta flower and synthesized ZnO NPs showed an excellent alternative source of antimicrobial agent also an attractive selective cytotoxic activity against HeLa tested cancer lines, offering satisfying ‘safe and cheaper’ alternatives to conventional therapy protocols.

α-amyrin-loaded nanocapsules produce selective cytotoxic activity in leukemic cells

IntroductionAmyrins are triterpenes that have attractive pharmacological potential; however, their low water solubility and erratic stomach absorption hinders their use as a drug. The aim of this paper was to develop a novel α-amyrin-loaded nanocapsule for intestinal delivery and evaluate, preliminarily, its cytotoxic ability against leukemic cells. Material and methodsFive nanocapsule formulations were designed by the solvent displacement-evaporation method. Poly-ε-caprolactone, Eudragit® E100, and Kollicoat® Mae 100 P were used as film-former materials. Particle size, polydispersity index (PdI), zeta potential, and the pH of all formulations were measured. The cytotoxic potential of the nanocapsules was evaluated in vitro using different leukemic lineages ResultsNanocapsules coated with Kollicoat® Mae 100 P presented the smallest particle size (130 nm), the lowest zeta-potential (−38 mV), and the narrowest size distribution (PdI = 0.100). The entrapment efficiency was 65.47%, while the loading capacity was 2.40%. Nanocapsules release 100% of α-amyrin in 40 min (pH 7.4), by using a possible mechanism of swelling-diffusion. The formulation showed excellent on-shelf physicochemical stability during one year. Additionally, nanocapsules produced a selective cytotoxic effect on a human leukemia lineage Kasumi-1, an acute myeloid leukemia cell line, and produced cell death by apoptosis Conclusionα-amyrin-loaded nanocapsules appear to be a promising nanoformulation that could be used against leukemia.

Defensin γ-thionin from Capsicum chinense improves butyrate cytotoxicity on human colon adenocarcinoma cell line Caco-2

Butyrate is a histone deacetylase inhibitor that induces apoptosis and inhibits cell proliferation of colorectal cancer cells. To improve its anticancer activity, butyrate has been evaluated mixed with drugs and different molecules. Plant antimicrobial peptides are attractive anticancer alternative molecules because they show selective cytotoxic activity against different cancer cell lines. In this work, we explore if the plant defensin γ-thionin (Capsicum chinense) can improve butyrate activity on Caco-2 cell line and we also determined the mechanism of death activated. The combined treatment of γ-thionin (3.5 µM) and butyrate (50 mM) showed higher cytotoxicity on Caco-2 cells with respect to single treatments. Also, the combined treatment reduced cell proliferation and exhibited a higher rate of apoptosis than single treatments. Combined treatment induced caspases 8 and 9 activation to an extent comparable with that of butyrate while γ-thionin did not activate caspases. Additionally, reactive oxygen species generation preceded the onset of apoptosis, and superoxide anion production was higher in cells treated with the combined treatment. The γ-thionin from Habanero chili pepper improved the butyrate cytotoxicity on Caco-2 cells. This effect occurred through apoptosis induction associated with reactive oxygen species production. Therefore, the combination of butyrate with cytotoxic antimicrobial peptides could be an attractive strategy for cancer therapy. How to cite: Velázquez-Hernández ME, Ochoa-Zarzosa A, López-Meza JE, Defensin γ-thionin from Capsicum chinense improves butyrate cytotoxicity on human colon adenocarcinoma cell line Caco-2. Electron J Biotechnol 2021;52. https://doi.org/10.1016/j.ejbt.2021.04.009

Synthesis, characterization, anti-proliferative activity and DFT study of 1H-benzo[f]chromene-2-carbothioamide derivatives

Reaction of 7‑methoxy-2-naphthol with appropriate aromatic aldehydes and 2-cyano-ethanethioamide provided the corresponding 3-amino-1-aryl-9‑methoxy-1H-benzo[f]chromene-2-carbothioamide. The structures of these compounds were established on the basis of IR, 1H NMR, 13C NMR, MS data and elemental analysis. Furthermore, the anti-proliferative properties were evaluated against the human cancer cell lines MCF-7, HepG-2 and PC-3 in comparison to the positive controls Vinblastine and Doxorubicin, employing the viability assay. The obtained results confirmed that some of the tested molecules revealed strong and selective cytotoxic activities against the three cancer cell lines. Moreover, various molecular descriptors, frontier molecular orbitals (FMO), Mulliken analysis and electronic properties were studied to probe the biological activity behavior of the synthesized 1H-benzo[f]chromene-2-carbothioamide derivatives. The effect of electron withdrawing groups (EWGs) and electron donating groups (EDGs) was also explored on the structural parameters and electronic nature of compounds. The energy gaps, reactivity descriptors values and molecular docking studies exhibited that some 1H-benzo[f]chromene-2-carbothioamide derivatives would be active biological compounds.

Synthesis, molecular modeling and biological evaluation of new benzo[4,5]thieno[3,2-b]pyran derivatives as topoisomerase I-DNA binary complex poisons

A series of new benzo[b]thiophenes 2a-f and benzo[4,5]thieno[3,2-b]pyran derivatives 3a-f and 4a-f were synthesized and their structures were confirmed by elemental analyses and spectral data. All synthesized compounds were evaluated by the National Cancer Institute (NCI, USA) against 60 human tumor cell lines. Compounds 3a-f and 4a-f showed potent cytotoxic effects in one dose assay with mean growth inhibition ranging from 62% to 80%. Six compounds 3a, 3d, 3e, 3f, 4d and 4e were selected by NCI, USA for five dose evaluation against 60 human tumor cell lines. Compounds 3a, 3d, 3e and 3f exhibited very potent and broad spectrum cytotoxicity against almost all cancer cell lines with mean concentration that yield 50% growth inhibition (MG-MID GI50) of 0.1–0.58 µM and mean concentration that produce 100% growth inhibition (MG-MID TGI) of 6.03–10.00 µM. Compounds 4d and 4e exhibited very potent and selective cytotoxic activity against MDA-MB-435 subpanel (melanoma cancer) with GI50 of 0.45 µM and 0.59 µM, respectively. The mechanism of antiproliferative activity was determined for the most active compounds 3a, 3d, 3e, 3f, 4d, and 4evia measuring their half maximal inhibitory concentration (IC50) against topoisomerase I enzyme at different concentrations. Compounds 3a and 3e exhibited excellent activity compared with reference drugs with IC50 of 0.295 µM and 0.219 µM, respectively. Plasmid DNA nicking assay verified that these compounds are topoisomerase I poisons not suppressors. The active compound 3e induced a significant disruption in the cell cycle profile parallel to its effect on apoptosis induction.

New polymerized sesquiterpene lactones from Ainsliaea yunnanensis and their activity evaluation

Two new dimeric and trimeric sesquiterpene lactones (1–2), and nine known sesquiterpene lactones (3–11) were isolated from the EtOAc phase of the ethanolic extract of Ainsliaea yunnanensis. Their structures were identified by NMR, IR and HR-ESIMS spectroscopic methods, and compound 1 was confirmed by single crystal X-ray diffraction experiment. All the compounds were tested for their cytotoxic, anti-microbial and anti-inflammatory activities. Compounds 1, 2, 3, 5, 7, 9 and 11 showed very significant selective cytotoxic activities on MDA-MB-468, PANC-1, HEPG2 or A549 cells. Compounds 6 and 11 showed very significant inhibiting effect on Epicoccum sp. (CPCC 400307), Fusarium solani (CPCC 800013) or Bacillus subtilis. Meanwhile, compounds 6 and 7 can inhibit the NLRP3 inflammasome’s activation at the concentration of 10 μM.

Synthesis of sorafenib analogues incorporating a 1,2,3-triazole ring and cytotoxicity towards hepatocellular carcinoma cell lines

A series of 1,2,3-triazole-containing Sorafenib analogues, in which the aryl urea moiety of Sorafenib (1) was replaced with a 1,2,3-triazole ring linking a substituted phenoxy fragment, were prepared successfully via Huisgen 1,3-dipolar cycloaddition and nucleophilic aromatic substitution. The studies of cytotoxicity towards human hepatocellular carcinoma (HCC) cell lines, HepG2 and Huh7, indicated that p-tert-butylphenoxy analogue 2m showed significant inhibitory activity against Huh7 with IC50 = 5.67 ± 0.57 µM. More importantly, 2m showed low cytotoxicity against human embryonal lung fibroblast cell line, MRC-5, with IC50 > 100 µM, suggesting its highly selective cytotoxic activity (SI > 17.6) towards Huh7 which is much superior to that of Sorafenib (SI = 6.73). The molecular docking studies revealed that the analogue 2m bound B-RAF near the binding position of Sorafenib, while it interacted VEGFR2 efficiently at the same binding position of Sorafenib. However, 2m exhibited moderate inhibitory activity toward B-RAF, implying that its anti-Huh7 effect might not strictly relate to inhibition of B-RAF. Wound healing and BrdU cell proliferation assays confirmed anti-cell migration and anti-cell proliferative activities towards Huh7. With its inhibitory efficiency and high safety profile, 2m has been identified as a promising candidate for the treatment of HCC.

Ubiquitin-specific protease 7 as a potential therapeutic target in dogs with hematopoietic malignancies.

BackgroundUbiquitin‐specific protease 7 (USP7) belongs to the group of deubiquitinating enzymes (DUBs), which remove ubiquitin which controls various cellular processes such as chromosome segregation, DNA repair, gene expression, protein localization, kinase activity, protein degradation, cell cycle progression, and apoptosis. It is critical for several important functions in the cell, and therefore dysregulation of USP7 can contribute to tumorigenesis.ObjectivesAlterations in the USP7 protein have been identified in various malignancies of humans. Our aim was to examine whether USP7 could be a potential therapeutic target in hematopoietic cancers of dogs.MethodsThe expression level of USP7 in lymphocytes from healthy dogs and canine lymphoma cells was determined, and the effect of USP7 inhibition on the vital functions of canine cancer cells was examined.ResultsWe showed that USP7 was overexpressed in lymphomas in dogs. The USP7 inhibitor P5091 has selective cytotoxic activity in canine lymphoma and leukemia cell lines. Our results indicate that inhibition of USP7 leads to a disruption of cell cycle progression, and triggers DNA damage and apoptosis. The observed proapoptotic effect of the USP7 inhibitor most likely is not dependent on the p53 pathway.Conclusions and Clinical ImportanceOur results suggest that USP7 could be explored as a potential therapeutic target in dogs with lymphoma. The effectiveness of USP7 inhibition in malignant cells is predicted to be independent of their p53 status.