HL-60 Cancer Cell Lines Research Articles

Labdane-type diterpenoids with cytotoxic and anti-inflammatory activities from the aerial parts of Hypoestes purpurea (L.) R. Br.

Two new ent-labdane diterpenoids, hypoestesins A-B (1–2) and five new labdane diterpenoids, hypopurolides H-L (3–7), were isolated from the aerial parts of Hypoestes purpurea. All of the structures were fully determined based on extensive analysis of 1H, 13C, 2D NMR, and HRESIMS data. The absolute configurations of 1–3 was established through comparing the experimental and calculated ECD curves and the structure of 5 was confirmed by single crystal X-ray diffraction experiment. Compounds 5–7 were unusual C23 labdane diterpenoids having a γ-acetonyl-α, β-unsaturated γ-lactone unit and each assigned as C-15 epimeric mixture. Furthermore, cytotoxic and anti-inflammatory activities of 3–7 were evaluated. The results showed that 3 had remarkable cytotoxic activity against HL-60, A549, SMMC-7721, MDA-MB-231, and SW480 cancer cell lines with IC50 values ranging from 2.35 to 17.06 μM. Compound 4 showed moderate cytotoxic activity against HL-60 and SMMC-7721 cancer cell lines with IC50 values of 15.12 ± 0.53 and 12.92 ± 0.60 μM, respectively. Furthermore, compound 4 was also found to exhibit inhibitory activity against NO production in RAW 264.7 macrophages with IC50 values of 23.56 ± 0.99 μM, compared to the positive control L-NMMA with an IC50 value of 41.11 ± 1.34 μM.

Effective delivery of anti-PD-L1 siRNA with human heavy chain ferritin (HFn) in acute myeloid leukemia cell lines.

Because of the high biocompatibility, self-assembly capability, and CD71-mediated endocytosis, using human heavy chain ferritin (HFn) as a nanocarrier would greatly increase therapeutic effectiveness and reduce possible adverse events. Anti-PD-L1 siRNA can downregulate the level of PD-L1 on tumor cells, resulting in the activation of effector T cells against leukemia. Therefore, this study aimed to produce the tumor-targeting siPD-L1/HFn nanocarrier. Briefly, the HFn coding sequence was cloned into a pET-28a, and the constructed expression plasmid was subsequently transformed into E. coli BL21. After induction of Isopropyl β-D-1-thiogalactopyranoside (IPTG), HFn was purified with Ni-affinity chromatography and dialyzed against PBS. The protein characteristics were analyzed using SDS-PAGE, Western Blot, and Dynamic light scattering (DLS). The final concentration was assessed using the Bicinchoninic acid (BCA) assay. The encapsulation was performed using the standard pH system. The treatment effects of siPD-L1/HFn were carried out on HL-60 and K-562 cancer cell lines. The RT-PCR was used to determine the mRNA expression of PD-L1. The biocompatibility and excretion of siPD-L1/HFn have also been evaluated. The expression and purity of HFn were well verified through SDS-PAGE, WB, and DLS. RT-PCR analyses also showed significant siRNA-mediated PD-L1 silencing in both HL-60 and K-562 cells. Our study suggested a promising approach for siRNA delivery. This efficient delivery system can pave the way for the co-delivery of siRNAs and multiple chemotherapies to address the emerging needs of cancer combination therapy.

Compounds from aerial parts of Isodon lophanthoides and their effects of cytotoxicity and LPS‐induced IL‐1β and IL‐10 production in RAW 264.7 macrophages

AbstractThe bioassay‐guided isolation of compounds from the aerial parts of Isodon lophanthoides (IL) resulted in the identification of five compounds (1–5). The chemical structures of 1–5 were determined through spectral analyses and compared to those identified in the literature to be 4‐hydroxybenzoic acid (1), protocatechuic acid (2), rosmarinic acid (3), coetsoidin B (4), and coetsoidin A (5). Compounds 1, 4, and 5 were found for the first time in the aerial parts of IL. Compounds 1 and 2 displayed potent cytotoxic activity against A549, MCF‐7, HepG2, and HL60 cancer cell lines, with IC50 values ranging from 13.93 to 18.69 µm and from 11.97 to 18.30 µm, respectively. Compounds 1‒5 significantly inhibited LPS‐induced IL‐1β production in RAW 264.7 macrophages compared to the LPS 5 ng/mL control group, resulting in IL‐1β concentrations ranging from 34.92 to 46.91 pg/mL. Additionally, compounds 1‒5 exhibited notable stimulation of IL‐10 production, with IL‐10 levels ranging from 358.77 to 478.23 pg/mL, compared to the LPS 5 ng/mL control group. These findings highlight the potential of compounds 1‒5 and the IL extracts for the cytotoxic effects on cancer cell lines and on LPS‐induced IL‐1β and IL‐10 production in RAW 264.7 macrophages.

Undescribed α-pyrone-containing mycotoxins and an eremophilane-type sesquiterpenoid isolated from Aspergillus aureoterreus and their cytotoxicity

Four previously undescribed and highly oxygenated α-pyrone-containing mycotoxins designated citreoviridins (E‒H), and an unreported eremophilane-type sesquiterpenoid namely aureoterrolide N, were isolated from the culture broth of Aspergillus aureoterreus. Those isolates were inferred from extensive spectroscopic methods and theoretical computation, where their absolute configurations were unambiguously determined by coupling constants following an empirical rule for the acyclic vicinal diol, theoretical ECD calculation, and NMR computation using the GIAO method and DP4+ analysis. Among them, citreoviridins E‒H are four stereoisomers of a citreoviridin derivative, featuring a methylated α-pyrone, an oxidized polyene linker, and a tetrahydrofuran ring. Cytotoxicity assay of all isolates demonstrated that aureoterrolide N exhibited weak inhibitory effect against human cancer cell line HL-60 with an inhibition rate of 55.2% at 40.0 μM.

Synthesis, enzyme inhibition assay, and molecular modeling study of novel pyrazolines linked to 4-methylsulfonylphenyl scaffold: antitumor activity and cell cycle analysis.

Antitumor activity using 59 cancer cell lines and enzyme inhibitory activity of a newly synthesized pyrazoline-linked 4-methylsulfonylphenyl scaffold (compounds 18a-q) were measured and compared with those of standard drugs. Pyrazolines 18b, 18c, 18f, 18g, 18h, and 18n possessed significant antitumor activity, with a positive cytotoxic effect (PCE) of 22/59, 21/59, 21/59, 48/59, 51/59, and 20/59, respectively. The cancer cell lines HL60, MCF-7, and MDA-MB-231 were used to measure the IC50 values of derivatives 18c, 18g, and 18hvia the MTT assay method, and the results were compared with those of reference drugs. Derivatives 18g and 18h showed potent and broad-spectrum antitumor activities against HL60 (IC50 of 10.43, 8.99 μM, respectively), MCF-7 (IC50 of 11.7 and 12.4 μM, respectively), and MDA-MB-231 (IC50 of 4.07 and 7.18 μM, respectively). Compound 18c exhibited strong antitumor activity against HL60 and MDA-MB-231 cell lines with IC50 values of 8.43 and 12.54 μM, respectively, and moderate antitumor activity against MCF-7 cell lines with an IC50 value of 16.20 μM. Compounds 18c, 18g, and 18h remarkably inhibited VEGFR2 kinase (IC50 = 0.218, 0.168, and 0.135 μM, respectively) compared with the reference drug sorafenib (IC50 = 0.041 μM). Compounds 18g and 18h effectively inhibited HER2 kinase (IC50 = 0.496 and 0.253 μM, respectively) compared with erlotinib (IC50 = 0.085 μM). Compound 18h inhibited EGFR kinase (IC50 = 0.574 μM) with a potency comparable with that of the reference drug erlotinib (IC50 = 0.105 μM). Pyrazolines 18c, 18f, and 18h arrested the S/G2 phase of the cell cycle in HL-60 cells. In addition, derivatives 18c, 18f, and 18h revealed lower Bcl-2 protein expression anti-apoptotic levels and higher Bax, caspase-3, and caspase-9 expression levels. Molecular docking studies of derivative 18h into the binding sites of EGFR, HER2, and VEGFR2 kinases explored the interaction mode of these pyrazoline derivatives and their structural requirements for antitumor activity.

Semisynthesis and Cytotoxic Activities of Novel Oxime Ester Derivatives of the Diterpene Stemodin

Stemodin (1) is a diterpene produced by Stemodia maritima L. (Scrophulariaceae) and shows antiviral and tumor cell proliferation inhibitory activities. Chemical modifications of 1 were performed to produce the known stemodinone (2), two new stemodinone oximes, Z (3) and E (4), and seven new oxime esters derivatives (5, 6, 7, 8, 9, 10, and 11). All derivatives were evaluated for their cytotoxic activity in HL60 (promyelocytic leukemia), SNB-19 (astrocytoma), HCT-116 (colon carcinoma), and PC3 (prostate) human cancer cell lines, and L929 (healthy murine cells). Oximes 3 and 4 showed lower cytotoxic values than 1 against all cancer cell lines tested. However, esters 9 and 10 exhibited cell growth inhibition percentages higher than 1 against PC3, SNB-19, and HCT-116 cancer cell lines, ranging from 62.96 to 94.27%. Many of these values exceed that presented by doxorubicin (66.05-86.87%). All compounds showed no cytotoxic effect on healthy cells at the tested concentration of 25 µg mL-1.

Drug repurposing for the identification of new Bcl-2 inhibitors: In vitro, STD-NMR, molecular docking, and dynamic simulation studies

BackgroundThe anti-apoptotic protein B-Cell Lymphoma 2 (Bcl-2) is a key target for the development of anti-cancer agents, as its overexpression can render cancer cells resistant to chemotherapeutic treatments. Aims and objectivesThe current study has systematically evaluated a library of FDA-approved drugs for Bcl-2 inhibition using a drug repurposing strategy via in vitro, biophysical, and in-silico techniques. Materials and methodsIn vitro anticancer activity was performed, followed by apoptosis assay. The selected compounds were subjected to Saturation Transfer Difference Nuclear Magnetic Resonance (STD-NMR) spectroscopy, molecular docking, and molecular dynamic simulation for ligand-protein interactions. Key findingsIn the initial screening, seventy-five (75) drugs were evaluated against the HL-60 (human blood promyelocytic leukemia) cancer cell line. Among them, paroxetine HCl, carvedilol, clomipramine HCl, and clomifene citrate showed significant anti-proliferative activity (IC50 = 9.733 ± 0.524, 11.940 ± 0.079, 12.376 ± 1.242, and 6.155 ± 0.363 μM, respectively), in comparison to the reference drug venetoclax (IC50 = 7.086 ± 0.041 μM). This indicated that the test drugs have comparable IC50 values to the standard drug. Furthermore, the drugs were able to induce apoptosis in HL-60 cells. These drugs showed interactions with Bcl-2 protein in STD-NMR analysis. Docking and MD simulation studies further supported the interaction of these drugs with Bcl-2 protein, mainly via hydrophobic contacts leading to stable drug-Bcl-2 complexes. SignificanceThis study, identifies paroxetine HCl, carvedilol, clomipramine HCl, and clomifene citrate as significant Bcl-2 inhibitors and needs further pre-clinical and clinical studies for potential anti-cancer agents' evaluation.

Melatonin-vorinostat hybrid ligands show higher histone deacetylase and cancer cell growth inhibition than vorinostat.

Anticancer drug conjugates are an emerging approach for future cancer treatment. Here, we report a series of hybrid ligands merging the neurohormone melatonin with the approved histone deacetylase (HDAC) inhibitor vorinostat, using melatonin's amide side chain (3a-e), its indolic nitrogen (5a-d), and its ether oxygen (7a-d) as attachment points. Several hybrid ligands showed higher potency thanvorinostat in both HDAC inhibition and cellular assays on different cultured cancer cell lines. In the most potent HDAC1 and HDAC6 inhibitors, 3e, 5c, and 7c, the hydroxamic acid moiety of vorinostat is linked to melatonin through a hexamethylene spacer. Hybrid ligands 5c and 7c were also found to be potent growth inhibitors of MCF-7, PC-3M-Luc, and HL-60 cancer cell lines. As these compounds showed only weak agonist activity at melatonin MT1 receptors, the findings indicate that their anticancer actions are driven by HDAC inhibition.

Antiproliferative polycyclic polyprenylated acylphloroglucinols from Garcinia paucinervis

Bioassay-guided isolation of the stems of Garcinia paucinervis led to one new adamantane-type polycyclic polyprenylated acylphloroglucinols (PPAPs), (-)-garpauvinin A (1), and four known analogues (2–5). The structure and absolute configuration of 1 was established via spectroscopic techniques and ECD method. All the isolates displayed moderate antiproliferative activity against HL-60, PC-3 and Caco-2 human cancer cell lines with IC50 values ranging from 0.81 to 19.92 μM, and exhibited low toxicity on WPMY-1 normal human cells, showing selectivity between normal and malignant prostate cells. The biosynthetic pathways of the isolated PPAPs were proposed.

Cytotoxic C-20 non-oxygenated ent-kaurane diterpenoids from Isodon wardii

Twenty new ent-kaurane diterpenoids, wardiisins A-T (1–20), along with two previously undescribed artefactual compounds (21 and 22) and twelve known analogues (23–34), were isolated from the aerial part of Isodon wardii. Their structures were elucidated by comprehensive analysis of spectroscopic data and single-crystal X-ray diffraction, and most of them were found to bear unusual C-12 oxygenation. Compounds 4, 7, 8, 19, 20, 21 exhibited remarkable cytotoxicity against the cancer cell lines HL-60, SMMC-7721, A-549, MDA-MB-231, and SW480, with IC50 values ranging from 0.3 to 5.2 μM. Moreover, 7 was found to induce G2/M cell cycle arrest and promote apoptosis in SW480 cell lines.

Five new limonoids isolated from Walsura robusta

Five new toosendanin limonoids with highly oxidative furan ring walsurobustones A-D (1–4), and one new furan ring degraded limonoid walsurobustone E (5) together with one known compound toonapubesic acid B (6) were isolated from the leaves of Walsura robusta. Their structures were elucidated by NMR and MS data. Especially, the absolute configuration of toonapubesic acid B (6) was confirmed by X-ray diffraction study. Compounds 1–6 exhibited good cytotoxicity against the cancer cell lines HL-60, SMMC-7721, A-549, MCF-7, and SW480.

Apoptotic effects of phenols from the twigs and leaves of Garcinia nujiangensis

In order to find potential agents for treating cancer disease in naturally occurring compounds, we conducted a systematic phytochemical investigation on the endemic species of Garcinia nujiangensis. Three new biphenyl derivatives (1–3) and one new polycyclic polyprenylated benzophenone (4), together with four known benzophenone analogues (5–8), have been isolated from the CH2Cl2 extract of the twigs and leaves of G. nujiangensis. Their structures were determined by detailed spectroscopic analyses and comparison with structurally related known analogues. Experimental and calculated ECD method was used to determine the absolute configuration of 1 and 4. Moreover, compounds 5–7 were isolated for the first time from this species. The cytotoxicities of the new compounds were evaluated using HL-60, HepG2, and A549 human cancer cell lines. Compound 4 showed more significant antiproliferative effects against HepG2 cells with an IC50 value of 11.38 ± 0.79 μM than that of three biphenyl derivatives. The morphological features of apoptosis were evaluated in 4-treated HepG2 cells. Compound 4 effectively prevented the cell cycle progression of HepG2 cells in G2 phase. Additionally, western blot analysis indicated that treatment of 4 on HepG2 cells led to decreased expression of anti-apoptotic Bcl-2 and pro-Caspase-3, and increased protein expression of both pro-apoptotic Bax and cleaved PARP with reference to β-actin. Overall, our results suggested that the active polycyclic polyprenylated benzophenone derivatives in the twigs and leaves of G. nujiangensis can be used as a valuable source of bioactive compounds for the pharmaceutical industry.

Total synthesis and biological evaluation of histone deacetylase inhibitor WF-3161.

A novel synthesis of the naturally occurring HDAC inhibitor WF-3161 is described. Key steps include the Matteson homologation to generate the stereogenic centres in the side chain, and Pd-catalysed C-H functionalisation to connect the side chain to the peptide backbone. WF-3161 was found to be highly selective for HDAC1, whereas no activity was observed towards HDAC6. High activity was also found against the cancer cell line HL-60.

New cytotoxic quinone analogues from the rhizomes of Arnebia euchroma

Two new quinone analogues, given the trivial names arneromas A–B ( 1–2 ) were isolated from the rhizome of Arnebia euchroma . Their structures were elucidated on the basis of extensive spectroscopic analyses. The absolute configurations of both compounds were determined by comparison of their calculated and experimental CD curves. In addition, compounds 1–2 were tested for their cytotoxic activities against HCT-8 and HL-60 cancer cell lines, and both of the compounds showed moderate inhibitory activities against HL-60 cell line with IC 50 values of 9.1 and 7.2 μ M, respectively. • Two new quinone analogues, arneromas A – B were isolated from the rhizome of Arnebia euchroma . • Their structures were elucidated on the basis of spectroscopic dada. • Compounds 1–2 had significant antitumor activity against HL-60 cells with IC 50 values at 9.1 and 7.2 μ M, respectively.

Subergorgines A–E, five new suberosanone-purine hybrids from the South China Sea gorgonian Subergorgia suberosa

Five new suberosanone-purine hybrids, namely subergorgines A–E (1–5), were isolated from the South China Sea gorgonian Subergorgia suberosa. Their structures were elucidated on the basis of extensive spectroscopic data and the absolute configurations were clarified by the theoretical ECD calculation. Compounds 1–5 were rare purine alkaloids merged with the same suberosanone moiety via different C (6)–N bridges. Cytotoxic activities of the isolates were tested. Compound 4 was found to be the most active against the HL-60 cancer cell line with an IC50 value of 14.3 μM. A plausible biosynthetic pathway for suberosanone-purine hybrids was also discussed.

Synthesis and biological evaluation of 4-(4-aminophenyl)-6-methylisoxazolo[3,4-b] pyridin-3-amine covalent inhibitors as potential agents for the treatment of acute myeloid leukemia

Fms-like tyrosine kinase 3 (FLT3) mutation has been strongly associated with increased risk of relapse, and the irreversible covalent FLT3 inhibitors had the potential to overcome the drug-resistance. In this study, a series of simplified 4-(4-aminophenyl)-6-methylisoxazolo[3,4-b] pyridin-3-amine derivatives containing two types of Michael acceptors (vinyl sulfonamide, acrylamide) were conveniently synthesized to target FLT3 and its internal tandem duplications (ITD) mutants irreversibly. The kinase inhibitory activities showed that compound C14 displayed potent inhibition activities against FLT3 (IC50 = 256 nM) and FLT3-ITD by 73 % and 25.34 % respectively, at the concentration of 1 μM. The antitumor activities indicated that C14 had strong inhibitory activity against the human acute myeloid leukemia (AML) cell lines MOLM-13 (IC50 = 507 nM) harboring FLT3-ITD mutant, as well as MV4-11 (IC50 = 325 nM) bearing FLT3-ITD mutation. The biochemical analyses showed that these effects were related to the ability of C14 to inhibit FLT3 signal pathways, and C14 could induce apoptosis in MV4-11 cell as demonstrated by flow cytometry. Fortunately, C14 showed very weak potency against FLT3-independent human cervical cancer cell line HL-60 (IC50 > 10 μM), indicating that it might have no off-target toxic effects. In light of these data, compound C14 represents a novel covalent FLT3 kinase inhibitor for targeted therapy of AML.

Phytochemical Analysis and Cytotoxic Activity of Hexane Extract from Lasiosphaera nipponica

Lasiosphaera nipponica finds therapeutic applications as a hemostatic in the traditional Japanese and Chinese medicines. The present study aimed to analyse the phytochemical compositions of two fractions from a hexane extract of L. nipponica by GC-MS analysis and evaluate the cytotoxic activity of these two fractions and a pure compound viz. ergosterol peroxide by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT assay). A hexane extract from L. nipponica was obtained by maceration technique and silica gel column chromatography of this hexane extract led to obtain two fractions and three pure compounds. The two fractions were analysed for phytochemical compositions by GC-MS and the presence of fatty acids, esters of fatty acids and ethyl 9-oxononanoate were identified. Additionally, these two fractions were evaluated for cytotoxic activity in P388, HL60, MCF7, HepG2 and J82 cancer cell lines in culture by MTT assay. Fraction 1 showed good activity in P388 and HL60 cancer cell lines with IC50 values of 9.8 and 18.2 μg/mL, respectively. Fraction 2 also showed good activity in P388 and HL60 cancer cell lines with IC50 values of 19.4 and 16.2 μg/mL, respectively. However, these two fractions did not show any appreciable activity in MCF7, HepG2 and J82 cancer cell lines. The three pure compounds were characterised as n-hexadecanoic acid, n-octadecanoic acid and ergosterol peroxide by spectroscopic means. Of these three pure compounds, only ergosterol peroxide was evaluated for cytotoxic activity in HL60, HepG2 and J82 cancer cell lines. Ergosterol peroxide showed an IC50 value of 82.2 μM (35.1 μg/mL) in HL60 cancer cell lines but it did not show any appreciable activity in HepG2 and J82 cancer cell lines. n-Hexadecanoic acid and n-octadecanoic acid were not evaluated for cytotoxic activity since they obtained in small quantity. From this study, we concluded that the fractions from a hexane extract of L. nipponica have therapeutically important phytochemicals and they exhibited promising cytotoxic activity in P388 and HL60 cancer cell lines. Further studies on L. nipponica are required to explore its therapeutic applications.

Isoquinoline alkaloids from two species of Thalictrum genus plants

The chemical constituents from the roots of Thalictrum cultratum and T. baicalense were investigated. By various isolation methods, such as silica gel, aluminium oxide, ODS, and Sephadex LH-20 column chromatographies, and semi-preparative HPLC, 11 simple isoquinoline alkaloids were isolated from the ethanol extract of the roots of these two plants, including a new compound, named dehydrothalflavine(1), and ten known ones(2-11): N-methylcorydaline(2), N-methylthalidaldine(3), thaliflavine(4), oxyhydrastinine(5), noroxyhydrastinine(6), dimethoxyisoquinolone(7), thalactamine(8), dehydronoroxyhydrastinine(9), 6,7-dimethoxy-2-methyl-1,2,3,4-tetrahydroisoquinoline(10), and isopicnarrhine(11). Their structures were elucidated on the basis of HR-ESI-MS and 1 D and 2 D NMR techniques. Compound 1 was a new isoquinoline alkaloid. Compound 11 was obtained from Tha-lictrum plant for the first time. All compounds did not show cytotoxic activities against HL-60, U937, HCT116, Caco-2, and HepG2 cancer cell lines.

Explorations of novel pyridine-pyrimidine hybrid phosphonate derivatives as aurora kinase inhibitors

For developing novel therapeutic agents with good anticancer activities, a series of novel pyridine-pyrimidine hybrid phosphonate derivatives4(a–q) were synthesized by the Kabachnik-Fields method using CAN as catalyst. The compound 4o exhibited the most potent anticancer activity with an IC50 value of 13.62 μM, 17.49 μM, 5.81 μM, 1.59 μM and 2.11 μM against selected cancer cell lines A549, Hep-G2, HeLa, MCF-7, and HL-60, respectively. Compound 4o displayed seven times more selectivity towards Hep-G2 cancer cell lines compared to the human normal hepatocyte cell line LO2 (IC50 value 95.33 μM). Structure-Activity Relationship (SAR) studies were conducted on the variation in the aromatic ring (five-membered heterocyclic ring, six-membered heterocyclic ring) and the variation of substituents on the phenyl ring (electron donating groups, electron withdrawing groups). Furthermore, the mechanism of anticancer activity was clarified by further explorations in bioactivity by using in vitro aurora kinase inhibitory activity and molecular docking studies. The results showed that the compound 4o at IC50concentrationdemonstrated distinctive morphological changes such as cell detachment, cell wall deformation, cell shrinkage and reduced number of viable cells in cancer cell lines. Compound 4o induced early apoptosis and late apoptosis of 27.7% and 6.1% respectively.

Two new α-pyrone-containing polyketides isolated from the fungus Aspergillus aureoterreus

Two undescribed α-pyrone-containing polyketide derivatives designated aurovertins V (1) and W (2), and a known analogue (3), were isolated from the fungus Aspergillus aureoterreus. Their structures including the absolute configuration were elucidated on the basis of extensive spectroscopic methods and theoretical ECD calculation. Compound 1 is the first example of aurovertins with a 7R configuration, whereas 2 comprises a S configuration for C-6 and a Z geometry of the double bond Δ8. Both 1 and 2 showed no cytotoxicity against human cancer cell lines HL-60, SU-DHL-2 and U266) at the concentration of 20.0 μM.