Tested Tumor Cell Lines Research Articles

Methyl chanofruticosinate type alkaloids from the aerial parts of Kopsia lancibracteolata Merr.

A chemical investigation on the 70% ethanol extract from the leaves and stems of Kopsia lancibracteolata Merr. resulted in the isolation of three new methyl chanofruticosinate type alkaloids, 12-hydroxyl prunifoline A (1), 12-hydroxyl prunifoline C (2), and N(4)-oxide prunifoline D (3). Structural elucidation of all the compounds was performed by spectral methods such as 1D- and 2D-NMR, IR, UV, and HR-ESI-MS. The isolated alkaloids were tested in vitro for cytotoxic potential against five tumor cell lines (BGC-823, HepG2, MCF-7, SGC-7901, and SK-MEL-2). As a result, alkaloid 3 exhibited significant cytotoxic activity against all tested tumor cell lines with IC50 values from 7.2 to 8.9 μM.

SAR study on N2,N4-disubstituted pyrimidine-2,4-diamines as effective CDK2/CDK9 inhibitors and antiproliferative agents.

Cyclin-dependent kinases (CDKs) are pivotal kinases in cell cycle transition and gene transcription. A series of N2,N4-diphenylpyrimidine-2,4-diamines were previously identified as potent CDK2/CDK9 inhibitors. To explore the SAR of this structural prototype, twenty-four novel N2,N4-disubstituted pyrimidine-2,4-diamines were designed and synthesized. Among them, twenty-one compounds exhibited potent inhibitory activities against both CDK2/cyclin A and CDK9/cyclin T1 systems, and the most potent CDK2 and CDK9 inhibitors, 3g and 3c, showed IC50 values of 83 nM and 65 nM respectively. Most of these compounds displayed significant inhibition against the tested tumor cell lines in the SRB assay, and in particular, remained active against the triple-negative breast cancer (TNBC) cell line MDA-MB-231. Flow cytometer analysis of compounds 2a, 2d and 3b in MDA-MB-231 cells indicated that these compounds induced cell cycle arrest in G2/M phase. Docking studies on compound 3g were performed, which provided conducive clues for further molecular optimization.

Delivery of [Ru(η6-p-cymene)Cl2{Ph2P(CH2)3SPh-κP}] using unfunctionalized and mercapto functionalized SBA-15 mesoporous silica: Preparation, characterization and in vitro study

SBA-15 (Santa Barbara Amorphous 15) mesoporous silica and its functionalized form (with 3-mercaptopropyltriethoxysilane) SBA-15~SH were used as carriers for [Ru(η6-p-cymene)Cl2{Ph2P(CH2)3SPh-κP}] complex, denoted as [Ru]. Prepared mesoporous silica nanomaterials were characterized by traditional methods. Materials without [Ru] complex did not show any cytotoxic activity against melanoma B16 and B16-F10 cell lines. On the contrary, materials containing [Ru] such as SBA-15|[Ru] and SBA-15~SH|[Ru], exhibited very high activity against tested tumor cell lines, moreover with similar inhibitory potential. According to the loaded amount of the [Ru] in SBA-15|[Ru] and SBA-15~SH|[Ru] the IC50 values are 1–2μM depending on the test used, thus in comparison to [Ru] alone the activity of nanomaterials containing [Ru] are elevated 3–6 times in vitro. However, the mechanism of apoptosis induction differs for these two mesoporous silica. Unlike reference [Ru] compound and SBA-15~SH|[Ru], SBA-15|[Ru] induces high caspase activation. Discrepancy in mechanism of drugs action at intracellular level points towards an influence of functionalization as well as availability of the drug. Moreover, both SBA-15|[Ru] and SBA-15~SH|[Ru] similarly to [Ru] are declining autophagy in B16 cell line.

Design of Novel 3-Pyrimidinylazaindole CDK2/9 Inhibitors with Potent In Vitro and In Vivo Antitumor Efficacy in a Triple-Negative Breast Cancer Model.

In the present study, a novel series of 3-pyrimidinylazaindoles were designed and synthesized using a bioinformatics strategy as cyclin-dependent kinases CDK2 and CDK9 inhibitors, which play critical roles in the cell cycle control and regulation of cell transcription. The present approach gives new dimensions to the existing SAR and opens a new opportunity for the lead optimizations from comparatively inexpensive starting materials. The study led to the identification of the alternative lead candidate 4ab with a nanomolar potency against CDK2 and CDK9 and potent antiproliferative activities against a panel of tested tumor cell lines along with a better safety ratio of ∼33 in comparison to reported leads. In addition, the identified lead 4ab demonstrated a good solubility and an acceptable in vivo PK profile. The identified lead 4ab showed an in vivo efficacy in mouse triple-negative breast cancer (TNBC) syngeneic models with a TGI (tumor growth inhibition) of 90% without any mortality growth inhibition in comparison to reported leads.

Cytotoxic monoterpenoid-type alkaloids from the aerial parts of Melodinus morsei

Three new monoterpenoid alkaloids, melomorines A–C (1–3), along with melohemsine B (4), were isolated from the 70% ethanol extract of the aerial parts of Melodinus morsei. Structural elucidation of all the compounds was performed on the basis of spectral data. All the compounds were tested in vitro for cytotoxic activities. As a result, alkaloids 1, 2, and 4 exhibited cytotoxicities against all the five tested tumor cell lines with IC50 value of less than 20 μM.

Cytotoxic lignans from the barks of Juglans mandshurica

Phytochemical investigation of the barks of Juglans mandshurica Maxim led to the isolation, purification, and identification of one new lignan named Juglansol A (1), along with nine known compounds (2–10). Their structures were determined by the results of UV, IR, CD, HRESIMS, 1D, and 2D NMR spectroscopic analysis. Compounds 1–10 were evaluated for their cytotoxicities against A549, HepG2, Hep3B, Bcap-37, and MCF-7 cell lines. The results showed that compound 2 possessed stronger cytotoxicities against the tested tumor cell lines compared with positive control 5-fluorouracil.

Design, synthesis, and cytotoxic activity of novel 7-substituted camptothecin derivatives incorporating piperazinyl-sulfonylamidine moieties

In our continuing search for camptothecin (CPT)-derived antitumor drugs, novel 7-substituted CPT derivatives incorporating piperazinyl-sulfonylamidine moieties were designed, synthesized and evaluated for cytotoxicity against five tumor cell lines (A-549, MDA-MB-231, MCF-7, KB, and KB-VIN). All of the derivatives showed promising in vitro cytotoxic activity against the tested tumor cell lines, and were more potent than irinotecan. Remarkably, most of the compounds exhibited comparable cytotoxicity against the multidrug-resistant (MDR) KB-VIN and parental KB tumor cell lines, while irinotecan lost activity completely against KB-VIN. Especially, compounds 13r and 13p (IC50 0.38 and 0.85μM, respectively) displayed the greatest cytotoxicity against the MDR KB-VIN cell line and merit further development into preclinical and clinical drug candidates for treating cancer, including MDR phenotype.

Cytotoxic gelsedine-type indole alkaloids from Gelsemium elegans

The ethanol extract of the leaves and branches of Gelsemium elegans afforded three new gelsedine-type indole alkaloids, 11-methoxy-14,15-dihydroxyhumantenmine (1), 11-methoxy-14,15-dihydroxy-19-oxogelsenicine (2), and 11-methoxy-14-hydroxygelsedilam (3), along with one known alkaloid 11-methoxy-14-hydroxyhumantenmine (4). The structures of isolated compounds were established based on 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high-resolution mass spectrometry. The isolated alkaloids were tested in vitro for cytotoxic potential against four laryngeal tumor cell lines including Hep-2, LSC-1, TR-LCC-1, and FD-LSC-1. As a result, compounds 1 and 4 exhibited some cytotoxic activities against all tested tumor cell lines with IC50 values of 10.9–12.1 μM and 9.2–10.8 μM, respectively.

Abstract 5126: Novel indolizino[8,7-b]indole hybrids with potent activity against small cell lung cancer

Abstract Small cell lung cancer (SCLC) is an aggressive type of lung cancer and accounts for 10% to 15% of all lung cancer cases. The malignancy has a greater tendency to be widely disseminated by the time of diagnosis as well as to develop early resistance to conventional treatments, a cure is difficult to achieve. The current standard therapy for SCLC treatment, either with monotherapy (platinum based drugs) or combination therapy (e.g., cisplatin with irinotecan or topotecan), was shown to cause serious side effects and inevitably evoke drug resistance in a short time period. We have recently synthesized a series of novel bis(hydroxymethyl)indolizino[8,7-b]indole hybrids by fusing β-carboline and bis(hydroxymethyl)pyrrole moieties for antitumor evaluation. These hybrid molecules displayed diverse mechanisms of action involving topoisomerase II (Topo II) inhibition and induction of DNA cross-linking. Our results also showed that they significantly inhibited the cell growth of various human tumor cell lines. Of the tested tumor cell lines, the SCLC cells (H526 and H211) were the most susceptible to compounds BO-2239 and BO-2329. These hybrids induced cell cycle arrest at the G2/M phase and triggered tumor cell apoptotic death. Intriguingly, the substituent at N11 (H or Me) played a critical role in modulating Topo II inhibition and DNA cross-linking. Compared to the compounds with N11-Me group, derivatives having N11-H group profoundly increased Topo II inhibition activity but reduced DNA cross-linking activity. Among these hybrids, BO-2239 (with N11-H) was as potent as irinotecan, but more effective than cisplatin, in nude mice bearing SCLC H526 xenografts. Accordingly, hybrid BO-2239 may be further developed as a potential agent for the treatment of SCLC. Citation Format: Sue-Ming Chang, Ming-Hsi Wu, Hima Bindu Pidugu, Tsann-Long Su, Te-Chang Lee. Novel indolizino[8,7-b]indole hybrids with potent activity against small cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 5126. doi:10.1158/1538-7445.AM2017-5126

Cytotoxic aspidofractinine alkaloids from Kopsia hainanensis

Five new aspidofractinine-type alkaloids, kopsiahainins A–E (1–5), were isolated from a 80% EtOH extract of the leaves and stems of Kopsia hainanensis. Structural elucidation of all the compounds were performed by spectral methods such as 1D- and 2D-NMR, IR, UV, and HR-ESI-MS. Alkaloids 3 and 4 exhibited some cytotoxic activity against all of six tested tumor cell lines (BGC-823, HepG2, MCF-7, SGC-7901, SK-MEL-2, and SK-OV-3) with IC50 values of 7.3–9.5μM and 9.2–10.6μM, respectively.

Novel 4-arylaminoquinazoline derivatives with (E)-propen-1-yl moiety as potent EGFR inhibitors with enhanced antiproliferative activities against tumor cells

A series of novel 4-anilinoquinazoline derivatives with (E)-propen-1-yl moiety were designed, synthesized and evaluated for biological activities in vitro. Most compounds exhibited highly antiproliferative activities against all tested tumor cell lines including A431, A549, NCI-H1975 and SW480 cells. Especially, compound 6e not only presented strong antiproliferative activities against the tested four tumor cell lines (IC50 of 1.35, 8.83, 5.53 and 6.08 μM, respectively) which expressed wild type or L858R/T790M double mutant epidermal growth factor receptor (EGFR), but also showed potent inhibitory activity against wild type EGFR (IC50 = 20.72 nM). The result of molecular docking with EGFR suggested the binding mode of 6e was similar to gefitinib, but different from lapatinib. Additionally, western blot analysis showed that 6e inhibited the phosphorylation of EGFR and its downstream signaling proteins in lung cancer cells. The work could be very useful starting point for developing a new series of tyrosine kinase inhibitors targeting EGFR.

Gelsedine-type oxindole alkaloids from Gelsemium elegans and the evaluation of their cytotoxic activity

Phytochemical investigation on the 70% EtOH extract of the leaves and branches of Gelsemium elegans resulted into the isolation of five new gelsedine-type oxindole alkaloids, gelseleganins A–E (1–5). The structures of the isolated compounds were established based on 1D and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to high resolution mass spectrometry. The isolated alkaloids were tested in vitro for cytotoxic potential against seven tumor cell lines. As a result, alkaloids 3 exhibited significant cytotoxic activities against all the tested tumor cell lines with IC50 values <10μM.

Design, Synthesis, and Biological Evaluation of Coumarin-Triazole Hybrid Molecules as Potential Antitumor and Pancreatic Lipase Agents.

The design, synthesis, and investigation of antitumor and anti-lipase activities of some coumarin-triazole hybrid molecules are reported. The synthesis of these hybrid molecules was performed under microwave irradiation and conventional heating procedures. The newly synthesized hybrid molecules were investigated as inhibitors against four tumor cell lines (BT20 human breast carcinoma, SK-Mel 128 melanoma, DU-145 prostate carcinoma, and A549 lung carcinoma) and porcine pancreatic lipase (PPL). Most of these compounds showed notable antitumor activities against the tested tumor cell lines, and compounds 8i and 8l showed the best anti-lipase activity of 99.30 ± 0.56% and 99.85 ± 1.21%, respectively, at a concentration of 10 μM.

DNA binding, cleavage, and cytotoxicity of binuclear phenolate nickel(II) complexes

Three binuclear phenolate complexes, [Ni2(L1)2(OAc)](BPh4)·DMF (1), [Ni2(L2)2(OAc)](BPh4) (2), and [Ni2(L3)2(OAc)](OH)·3H2O (3), where L1 = 2-{[bis-(2-hydroxy-ethyl)-amino]-methyl}-4-methyl-phenol, L2 = 2-{[bis-(2-hydroxy-ethyl)-amino]-methyl}-4-methoxy-phenol, and L3 = 2-{[bis-(2-hydroxy-ethyl)-amino]-methyl}-4-tert-butyl-phenol), have been synthesized. Single-crystal diffraction reveals that all the metal atoms are in a distorted octahedral geometry. The interactions of the complexes with calf thymus DNA (CT-DNA) have been investigated by UV–vis absorption, fluorescence emission, and circular dichroism spectroscopy and viscosity measurements. Furthermore, DNA cleavage mechanism shows that the complexes may be capable to promote DNA cleavage through oxidative DNA damage pathway, which is indicative of the involvement of hydroxyl radical, singlet oxygen, or singlet oxygen-like entity in the cleavage process. Cytotoxicity studies on the Hela and MCF-7 cancer cell lines show that complexes 1–3 exhibit excellent activity toward the tested tumor cell lines with respect to the standard drug carboplatin, revealing that they have the potential to act as effective metal-based anticancer drugs.

Monoterpenoid indole alkaloids from Alstonia mairei and their cytotoxicity

Phytochemical investigation on the 70% ethanol extract of the leaves of Alstonia mairei resulted in the isolation of three new monoterpenoid indole alkaloids, alstomairines A–C (1–3), along with one known compound, alpneumine A (4). Structural elucidation of all the compounds was accomplished by spectral methods such as 1D and 2D NMR, IR, UV, and HRESIMS. The isolated compounds were tested in vitro for cytotoxic activities against four osteosarcoma cell lines. Consequently, alkaloids 2 and 3 exhibited cytotoxic activities for all tested tumor cell lines with IC50 values from 9.2 to 13.0 μM.

Synthesis of 5α,8α-Ergosterol Peroxide 3-Carbamate Derivatives and a Fluorescent Mitochondria-Targeting Conjugate for Enhanced Anticancer Activities.

Inspired by the significant anticancer activity of our previously screened natural ergosterol peroxide (1), we synthesized and characterized a series of novel ergosterol peroxide 3-carbamate derivatives. The antiproliferative activities of the synthesized compounds against human hepatocellular carcinoma cells (HepG2, SK-Hep1) and human breast cancer cells (MCF-7, MDA-MB231) were investigated. 5α,8α-Epidioxyergosta-3-yl-(piperazine-1)carbamate (3 d) and 5α,8α-epidioxyergosta-3-yl-(piperidin-4-methylamine)carbamate (3 f) and their hydrochloride salts exhibited significant in vitro antiproliferative activities against the tested tumor cell lines, with IC50 values ranging from 0.85 to 4.62 μm. Furthermore, fluorescent imaging showed that the designed coumarin-3 d conjugate (5) localized mainly in mitochondria, leading to enhanced anticancer activities over the parent structure 1. As a whole, it appeared that substituent changes at the C3 position could serve as a promising launch point for further design of this type of steroidal anticancer agent.

The Hexane Fraction of Bursera microphylla A. Gray Induces p21-Mediated Anti-Proliferative and Pro-Apoptotic Effects in Human Cancer-Derived Cell Lines.

Bursera microphylla (BM), one of the common elephant trees, is widely distributed in the Sonoran Desert in Mexico. The Seri ethnic group in the Sonoran Desert uses BM as an anti-inflammatory and painkiller drug for the treatment of sore throat, herpes labialis, abscessed tooth, and wound healing. Dried stems and leaves of BM are used in a tea to relieve painful urination and to stimulate bronchial secretion. Furthermore, BM is used for fighting venereal diseases. To investigate the effects of the hexane fraction of resin methanol extract (BM-H) on cell growth, the acute myeloid cell line (OCI-AML3) was treated with 250, 25, or 2.5 µg/mL of BM-H. The first 2 concentrations were able to significantly decrease OCI-AML3 cell number. This reduced cell number was associated with decreased S-phase, blockade of the G2/M phase of the cell cycle, and increased cell death. Similar results were obtained on all tested tumor cell lines of different origins. We found that blockade of the cell cycle was due to upregulation of p21 protein in a p53-independent way. Increase of p21 was possibly due to upstream upregulation of p-ERK (which stabilizes p21 protein) and downregulation of p-38 (which promotes its degradation). Regarding cell death, activation of caspase-3, but not of caspase-8 or -9, was detectable after BM-H treatment. In conclusion, these data suggest that the BM’s hexane fraction inhibited proliferation of cell lines mainly by a p21-dependent, p53-independent mechanism and promoted apoptosis through activation of caspase-3, but not caspase-8 or -9.

Combination of amino acid/dipeptide with ligustrazine-betulinic acid as antitumor agents

The lead compound TBA, 3β-Hydroxy-lup-20(29)-ene-28-oic acid-3, 5, 6-trimethylpyrazin-2-methyl ester, which exhibited promising antitumor activity and induced tumor cell apoptosis in various cancer cell lines, had previously been reported. Moreover, reports have revealed that the introduction of amino acid to betulinic acid could improve selective cytotoxicity as well as water solubility. Thus, a series of novel TBA amino acid and dipeptide derivatives were designed, synthesized and screened for selective cytotoxic activity against five cancer cell lines (HepG2, HT-29, Hela, BCG-823 and A549) and the not malignant cell line MDCK by standard MTT assay. Most of the tested TBA-amino acid and dipeptide analogues showed stronger anti-proliferative activity against all tested tumor cell lines than TBA. Among them, BA-25 exhibited the greatest cytotoxic activity on tumor cell lines (mean IC50 = 2.31 ± 0.78 μM), that was twofold than the positive drug cisplatin (DDP), while it showed lower cytotoxicity on MDCK cell line than DDP. Further cell apoptosis analyses indicated BA-25-induced apoptosis was associated with loss of mitochondrial membrane potential and increase of intracellular free Ca2+ concentration.

Synthesis and in vitro biological evaluation of novel quinazoline derivatives

A series of novel 4-arylamino-6-(5-substituted furan-2-yl)quinazoline derivatives were designed, synthesized and evaluated on biological activities in vitro. Compound 2a, 3a and 3c exhibited highly anti-proliferation activities on all tested tumor cell lines including SW480, A549, A431 and NCI-H1975 cells. Especially, compound 2a not only exhibited strong anti-proliferation activities against the tumor cell lines which expressed wild type or mutant EGFRL858R/T790M, but also showed the most potent inhibitory activity toward wild type EGFR (IC50=5.06nM). The result of docking with EGFR suggested the binding mode of 2a was similar to that of lapatinib. While Western-blot analyses showed 2a obviously inhibited the activation of EGFR, Akt and Erk1/2 in lung cancer cells at indicated concentration. It is believed that this work would be very useful for developing a new series of TKIs targeting EGFR.

Nitric oxide-releasing nanoparticles: synthesis, characterization, and cytotoxicity to tumorigenic cells

Nitric oxide (NO) is involved in several biological processes, including toxicity against tumor cells. The aim of this study was to synthesize, characterize, and evaluate the cytotoxicity of NO-releasing chitosan nanoparticles. A thiol-containing molecule, mercaptosuccinic acid (MSA), was encapsulated (encapsulation efficiency of 99%) in chitosan/sodium tripolyphosphate nanoparticles (CS NPs). The obtained nanoparticles showed an average hydrodynamic size of 108.40 ± 0.96 nm and polydispersity index of 0.26 ± 0.01. MSA-CS NPs were nitrosated leading to S-nitroso-MSA-CS NPs, which act as NO donor. The cytotoxicity of CS NPs, MSA-CS NPs, and S-nitroso-MSA-CS NPs were evaluated in several tumor cells, including human hepatocellular carcinoma (HepG2), mouse melanoma (B16F10), and human chronic myeloid leukemia (K562) cell lines and Lucena-1, a vincristine-resistant K562 cell line. Both CS NPs and MSA-CS NPs did not cause toxic effects in these cells, whereas S-nitroso-MSA-CS NPs caused potent cytotoxic effects in all the tested tumor cell lines. The half-maximal inhibitory concentration values of S-nitroso-MSA-CS NPs were 19.7, 10.5, 22.8, and 27.8 μg·mL−1 for HepG2, B16F10, K562, and Lucena-1 cells, respectively. In contrast, S-nitroso-MSA-CS NPs exhibited lower cytotoxic to non-tumorigenic melanocytes (Melan-A) when compared with melanoma B16F10. Therefore, the results highlight the potential use of NO-releasing CS NPs in antitumor chemotherapy.