Strong Antiproliferative Activity Research Articles

Synthesis and biological activities of simplified aplysiatoxin analogs focused on the CH/π interaction

Debromoaplysiatoxin (DAT) is a potent protein kinase C (PKC) activator with tumor-promoting and pro-inflammatory activities. Irie and colleagues have found that 10-methyl-aplog-1 (1), a simplified analog of DAT, has strong anti-proliferative activity against several cancer cell lines with few adverse effects. Therefore, 1 is a potential lead compound for cancer therapy. We synthesized a new derivative 2 which has a naphthalene ring at the side chain terminal position instead of a benzene ring, to increase CH/π interactions with Pro-241 of the PKCδ-C1B domain. Based on the synthetic route of 1, 2 was convergently synthesized in 26 linear steps from 6-hydroxy-1-naphthoic acid with an overall yield of 0.18%. Although the anti-proliferative activity of 2 was more potent than that of 1, the binding potency of 2 to the PKCδ-C1B domain did not exceed that of 1. Molecular dynamics simulation indicated the capability of 2 to simultaneously form hydrogen bonds and CH/π interactions with the PKCδ-C1B domain. Focusing on the hydrogen bonds, their geometry in the binding modes involving the CH/π interactions seemed to be sub-optimal, which may explain the slightly lower affinity of 2 compared to 1. This study could be of help in optimizing such interactions and synthesizing a promising lead cancer compound.

Cyclic bridged analogs of isoCA-4: Design, synthesis and biological evaluation.

In this work, a series of cyclic bridged analogs of isocombretastatin A-4 (isoCA-4) with phenyl or pyridine linkers were designed and synthesized. The synthesis of the desired analogs was performed by the formation of nitro-vinyl intermediates, followed by a Cadogan cyclization. Structure activity relationship (SAR) study demonstrates the critical role of the combination of quinaldine as ring A, pyridine as the linker, and indole as ring B in the same molecule, for the cytotoxic activity. Among all tested compounds, compound 42 showed the highest antiproliferative activity against a panel of cancer cell lines with average IC50 values of 5.6nM. Also, compound 42 showed high antiproliferative activity against the MDR1-overexpressing K562R cell line; thus, it was 1.5- and 12-fold more active than the reference compounds, isoCA-4 and CA-4, respectively. Moreover, 42 displayed a strong antiproliferative activity against the colon-carcinoma cells (HT-29), which are resistant to combretastatin A-4 and isoCA-4, and it was found to be 8000-fold more active than natural CA-4. Compound 42 also effectively inhibited tubulin polymerization both invitro and in cells, and induced cell cycle arrest in G2/M phase. Next, we demonstrated that compound 42 dose-dependently caused caspase-induced apoptosis of K562cells through mitochondrial dysfunction. Finally, we evaluated the effect of compound 42 in human no cancer cells compared to the reference compound. We demonstrated that 42 was 73 times less cytotoxic than isoCA-4 in quiescent peripheral blood lymphocytes (PBLs). In summary, these results suggest that compound 42 represents a promising tubulin inhibitor worthy of further investigation.

Quantification of cardenolide glycosides and antiproliferative activity from a crop of the medicinal plant Asclepias subulata

The development of phytopharmaceuticals for the treatment of diseases such as cancer is a necessity, and its development requires to establish the conditions of commercial cultivation of the plant. Asclepias subulata has exhibited potent antiproliferative activity due to its cardenolide glycoside content. This work aimed to determine the cardenolide profile and antiproliferative activity of ethanolic extracts of A. subulata obtained from an experimental crop under different water stress treatments. Asclepias subulata was germinated in a shade house and was transplanted to the field in spring under different conditions: drought (D), drought with hydrogel (DG), drought with double row (DD), irrigation (I), irrigation with hydrogel (IG), and irrigation with double row (ID). For 12 months, biomass, concentration of calotropin and corotoxigenin 3-O-glucopyranoside, and antiproliferative activity were evaluated. The results showed the lower biomass for D treatments (283 g plant-1) while the I treatments showed the highest biomass (831 g plant-1). In general, the concentration of cardenolides was higher under drought treatments: for corotoxigenin 3-O-glucopyranoside, it was 530 μg g-1 while for calotropin, it was 204 μg g-1 dry weight. The ethanolic extracts showed strong antiproliferative activity and selectivity in the A549 cell line (human alveolar carcinoma). The D treatment showed an IC50 <2 μg mL-1 while in ARPE-19 (retinal pigment epithelia cell line), it was IC50 (the half maximal inhibitory concentration)> 200 μg mL-1. Based on findings in the present work, it can be concluded that A. subulata can be cultivated with a high production of the active compounds. This work represents an important advance in the studies for the potential development of a phytopharmaceutical based on A. subulata.

Synthesis, biological evaluation, in silico modeling and crystallization of novel small monocationic molecules with potent antiproliferative activity by dual mechanism.

Seeking for new anticancer drugs with strong antiproliferative activity and simple molecular structure, we designed a novel series of compounds based on our previous reported pharmacophore model composed of five moieties. Antiproliferative assays on four tumoral cell lines and evaluation of Human Choline Kinase CKα1 enzymatic activity was performed for these compounds. Among tested molecules, those ones with biphenyl spacer showed betters enzymatic and antiproliferative activities (n-v). Docking and crystallization studies validate the hypothesis and confirm the results. The most active compound (t) induces a significant arrest of the cell cycle in G0/G1 phase that ultimately lead to apoptosis, following the mitochondrial pathway, as demonstrated for other choline kinase inhibitors. However additional assays reveal that the inhibition of choline uptake could also be involved in the antiproliferative outcome of this class of compounds.

Efficacy of red light for enhanced cell disruption and fluorescence intensity of phycocyanin

In this study, red LED and urea used as light and nitrogen sources, respectively, for the cultivation of Spirulina to enhance the fluorescence property and purity of phycocyanin. Besides, there is a high concentration of phycocyanin leached out from red light (RL) grown cells than white light (WL) without cell disruption. This type of cultivation reduces the complexity of extraction methods and cost of the downstream process. The fluorescence intensity of C-PC enhanced while using red LEDs and purity ratio improved by single-step cation exchange chromatography. Phycocyanin from red-light-exposed culture exhibited pronounced antibacterial activity against bacteria. The hydrogen peroxide scavenging activity of C-PC (93.7%) is higher than the WL cultures (88.8%). Phycocyanin from RL culture exhibited a strong antiproliferative activity (64.1%) against HeLa cancer cell line. The present study aims to analyze the influence of red light and urea on enhancing the phycocyanin production.

The first small molecules capable of strongly suppressing proliferation of cancer cells harboring BRAF class I/II/III mutations

BRAF mutants are categorized into three classes according to dependency on RAS signaling and RAF dimerization-dependency. Class I BRAF V600 mutants (RAS-independent monomer) are sensitive to vemurafenib. In contrast, both class II mutants (RAS-independent dimer) and class III mutants (RAS-dependent heterodimer) are insensitive to vemurafenib. It is not likely that BRAF inhibitors capable of inhibiting all classes of BRAF mutants are currently available. Herein, we report GNF-7 and its novel derivative, SIJ1227 as the first BRAF inhibitors capable of inhibiting all classes of BRAF mutants. Compared with vemurafenib and PLX8394, both GNF-7 and SIJ1227 possess much more strong anti-proliferative activities on melanoma (A375 and C8161) and lung cancer cells (H1755 and H1666) harboring BRAF V600E (class I mutant), BRAF G464E/G469A (class II mutant) and BRAF G466V (class III mutant), respectively. Also, both GNF-7 and SIJ1227 are capable of inhibiting more strongly colony formation than vemurafenib and PLX8394 in 3D soft agar assay using C8161 melanoma cells. In addition, GNF-7 and SIJ1227 suppress more strongly migration/invasion of these cancer cells than vemurafenib and PLX8394. Taken together, both GNF-7 and SIJ1227 are much superior to vemurafenib and PLX8394 in terms of capability to inhibit all classes of BRAF mutants.

Bioassay-guided isolation and antiproliferative efficacy of extract loaded in chitosan nanoparticles and LC-QTOF-MS/MS analysis of Achillea magnifica

This study investigated the antioxidant, anti-urease, anticholinesterase, and antiproliferative activities of different extracts of A. magnifica. The active compounds were isolated from chloroform extract, which has the strongest antiproliferative and antioxidant activities. The structures of the isolated compounds (elenolic acid, luteolin, eupatilin) were examined using spectroscopic techniques (NMR, UV, HR-MS). The antioxidant and antiproliferative effects of isolated compounds showed lower biological activity than those of the chloroform extract. Therefore, chitosan nanoparticles were prepared with this extract and characterized. The cytotoxic activities of the chitosan nanoparticles were examined, and they were found to have a strong antiproliferative activity similar to that of the chloroform extract. The ethanol extract had strong anti-urease and anticholinesterase activity compared with other extracts. Therefore, phenolic compounds that might be responsible for the biological activity were analysed by LC-QTOF-MS/MS. The ferulic acid derivative, apigenin-6-C-pentoside-8-C-hexoside, apigenin 6,8-di C-hexoside, vitexin, and diosmetin 8-C-glucoside (orientin 4′-methyl ether) compounds from this plant were analysed for the first time. The results showed that the chloroform-loaded chitosan nanoparticles had a strong antiproliferative activity in breast cancer cell lines (MCF-7, MDA-MB-231) and no toxic effect on normal cell lines (L-929), which suggested that this extract might be a potential candidate as a herbal medicine that can be investigated and evaluated in future cancer studies. Additionally, the potential use of ethanol extract as an anti-urease and anticholinesterase agent was revealed.

Abstract 663: The dual PI3K-δ/PI3K-γ inhibitor duvelisib inhibits signaling and proliferation of solid tumor cells expressing PI3K-δ and/or PI3K-γ

Abstract Duvelisib is an oral, dual PI3K-δ,γ inhibitor that is FDA-approved for treatment of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma (SLL) and follicular lymphoma (FL) following ≥2 prior systemic therapies. In addition to targeting malignant B cells, duvelisib regulates key non-malignant immune cells in the tumor microenvironment (TME), including Tregs and immunosuppressive myeloid cells. However, direct effects of duvelisib on solid tumor cells have not been tested. Here, we used the GEPIA webserver to analyze the expression of PIK3CD [PI3K-δ] and PIK3CG [PI3K-γ] from the TCGA database. Whereas PIK3CG was highly expressed in hematological malignancies (log2 median transcript per million, TPM+1 &amp;gt; 2) but not in solid tumors, PIK3CD was highly expressed in hematological malignancies (log2TPM+1 = 5.1 in DLBCL) as well as in a number of solid tumors, including melanoma (log2TPM+1 = 4.4) and head and neck squamous cell carcinoma (HNSCC) (log2TPM+1 = 3.2). Further, PIK3CD was more highly expressed in melanoma and HNSCC human tumor samples compared to adjacent normal tissue, suggesting a potential tumorigenic role of PI3K-δ. We also checked the expression of PIK3CD in human tumor cell lines from the Cancer Cell Line Encyclopedia database and found that 57% and 22% of the melanoma and HNSCC cell lines, respectively, expressed high levels (log2TPM+1 &amp;gt; 2) of PIK3CD, while 7% of melanoma cell lines expressed high levels of PIK3CG. To assess possible direct effects of duvelisib on solid tumor cells, the growth inhibitory activity of duvelisib was evaluated across 7 melanoma and 3 HNSCC cell lines expressing high levels of PI3K-δ and/or PI3K-γ. Cell viability was measured after 72-hour treatment with duvelisib (0.5nM-10μM) and reported as growth inhibition (GI) at 1μM. Duvelisib showed strong anti-proliferative activity (50-100% GI) in 3 out of 7 melanoma cell lines and 1 out of 3 HNSCC cell lines, and moderate activity (15-50% GI) in 3 melanoma cell lines and an additional HNSCC cell line. Duvelisib inhibited PI3K pathway activity, as measured by p-AKT and c-myc, in all the cell lines in which strong anti-proliferative activity was observed. Taken together, these findings indicate that in addition to the established effects of duvelisib on malignant B cells and non-malignant immune cells of the TME, duvelisib can also directly inhibit signaling and proliferation of solid tumor cells expressing PI3K-δ and/or PI3K-γ, providing further rationale for clinical investigation of duvelisib for the treatment of solid tumors. Accordingly, the combination of duvelisib with pembrolizumab is currently being evaluated in patients with head and neck squamous cell carcinoma. Citation Format: SILVIA COMA, David T. Weaver, Jonathan A. Pachter. The dual PI3K-δ/PI3K-γ inhibitor duvelisib inhibits signaling and proliferation of solid tumor cells expressing PI3K-δ and/or PI3K-γ [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 663.

Abstract 1836: ONC201 shows synergistic effect with the androgen receptor AR-inhibitor darotulamide in prostate cancer models

Abstract Prostate cancer (PC) is the most frequently diagnosed cancer among men in the United States and is the 3rd cause of cancer mortality. Despite advances in the treatment and understanding of pathogenesis, patients with metastatic PC invariably progress to a lethal stage of castration-resistant prostate cancer (CRPC). Inhibition of androgen signaling remains crucial for the treatment of CRPC, but novel treatment strategies are urgently needed. ONC201 is a first-in-class, selective inhibitor of dopamine receptor D2 that upregulates death-receptor 5 and induces apoptosis. ONC201 induced apoptosis in PC cell lines and showed synergy with enzalutamide, docetaxel and everolimus (Lev A Mol Cancer Res 2018). Darolutamide (DARO) is a novel androgen receptor (AR) antagonist approved for treatment of patients with non-metastatic CRPC. DARO has higher affinity to AR and preclinical activity against enzalutamide-resistant PC cell lines including AR variants associated with enzalutamide agonism (Borgmann H Eur Urol 2018). We treated human PC cell lines (LNCAP [castration sensitive, AR wild-type], 22Rv1 [castration-resistant cell line that expresses AR splice variant AR-V7], DU145 [AR negative], PC3 [AR negative]) with DARO alone and combined with ONC201. Single-agent DARO decreased PC cell viability in Cell-Titer-Glo assays (IC50s of 10 and 693 nM for LNCAP and DU145, respectively). ONC201 showed strong synergism with DARO in LNCAP cells (combination indices &amp;lt; 1 at concentrations of 156, 312, 625 nM, and 1.25 µM of DARO with 2.5 μM ONC201). ONC201 induced robust apoptosis in 22Rv1 as measured by PARP cleavage, which was partially amplified by DARO. PARP cleavage was also observed in LNCAP cells with less intensity and not potentiated by DARO. ONC201 reduced the expression of phospho-AR (p-AR) in both 22Rv1 and LNCAP. The combination of ONC201 and DARO had a significant additive effect in reducing p-AR in 22Rv1, but not in LNCAP. ONC201 reduced PSA protein levels in LNCAP cells while DARO alone did not cause any significant change in PSA. Immunofluorescence experiments showed that DARO caused significant reduction of AR nuclear translocation in both 22rV1 and LNCAP cells. The combination with ONC201 potentiated this inhibition of AR translocation in both cell lines. ONC201 showed strong antiproliferative activity against PC cells lines independent of AR status. Combination of ONC201 with DARO demonstrated synergy in enzalutamide resistant 22Rv1 cells expressing AR-V7 with marked reduction of nuclear localization of AR. Our studies provide preclinical rationale for combination of ONC201 with DARO as a novel therapy of PC. Citation Format: Fabio Tavora, Lanlan Zhou, Ali Amin, Safran Howard, Navaraj Arunasalam, Andre de Souza, Anthony Mega, Dragan Golijanin, Wafik El-Deiry, Benedito Carneiro. ONC201 shows synergistic effect with the androgen receptor AR-inhibitor darotulamide in prostate cancer models [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1836.

Abstract 1756: JBI-802, novel dual inhibitor of LSD1-HDAC6 for treatment of cancer

Abstract Introduction: Lysine Specific Demethylase 1 (LSD1) is over-expressed in many cancers and down-regulation of LSD1 has been shown to effectively treat cancers by inducing re-expression of aberrantly silenced genes. Studies have shown that LSD1 may contribute to acute myelogenous leukaemia pathogenesis by inhibiting the normal pro-differentiative function of ATRA, paving the way for new combinatorial therapies for AML. In addition, LSD1 inhibition also leads to convertion of ‘cold' tumors to ‘hot' tumors by activating type 1 interferon response. Similarly, HDAC6 inhibition enhances immune response by over-coming immune suppression. Further, combined inhibition of LSD1 and HDAC has been shown to be more efficacious in inhibiting multiple cancers. Here, we show that JBI-802, a dual inhibitor targeting both LSD1 and HDAC6/8 shows stronger efficacy in several cancers, including AML, lymphoma and others and well tolerated at efficacious doses. Methods: Computational chemistry approaches were used to design LSD1 specific and LSD1-HDAC dual inhibitors. To assess in vitro LSD1 potency, TR-FRET assay was used. For assessing in vitro HDAC activity fluorescence based HDAC6 activity assay was performed. Western blotting and quantitative PCR were used to assess biomarkers of LSD1 and HDAC inhibition. Alamar blue cytotoxicity assay was used to assess cell proliferation. Xenograft and syngeneic models were used to assess in vivo efficacy. Results: Several compounds from this series show strong in vitro potency against LSD1 with excellent selectivity against MAOs. JBI-802 our lead dual molecule, showed an IC50 of 0.05 μM against LSD1 and isoform selective HDAC6/8 activity (IC50 of 0.011 and 0.098 µM on HDAC6 and HDAC8, respectively), with about 100 fold selectivity against other HDAC isoforms. When assessed in a panel of 25 cell lines, JBI-802 showed strong anti-proliferative activity on select AML, CLL, SCLC, sarcoma and multiple myeloma cell lines. In cell based and in vivo target engagement studies there was significant dose-dependent increase in CD11b, CD86 and GFI1b and tubulin acetylation levels. JBI-802 had a much stronger effect in inhibiting the growth of HEL92.1.7 erythroleukemia xenograft by oral administration when compared to ACY-1215, a HDAC6 selective inhibitor or ORY-1001 an LSD1 selective inhibitor. ED50 of JBI-802 in this model was ~6.25 mg/kg BID. Further, dose-dependent modulation of above mentioned biomarkers and inhibition of c-Myc could be observed in tumors. Stronger tumor growth inhibition was also observed in other haematological cancers models such as CMK-1 (leukemia) and Z-138 (lymphoma). In addition, JBI-802 showed comparable single agent activity to anti-PD-1/PD-L1 mAbs in a syngeneic murine colon cancer model CT26 and resulted in stronger tumor growth inhibition when combined with these antibodies. 14-day dose ranging finding toxicology studies clearly show that the molecule was well tolerated up to 300 mg/kg. Conclusion: The data obtained to date demonstrate that dual LSD1-HDAC6/8 inhibitors could serve as novel, effective therapeutic agents for treatment of select subset of AML and other cancers. IND-enabling studies are in progress with this inhibitor to be developed as a clinical candidate Citation Format: Dhanalakshmi Sivanandhan, Sridharan Rajagopal, Sreekala Nair, Basavaprabhu B, Reshma Dhkar, Santosh Viswakarma, Amir Siddiqui, Mohd Zainuddin, Rudresh G, Prashanthi Daram, Sunil Mohire, Krishnakumar V. JBI-802, novel dual inhibitor of LSD1-HDAC6 for treatment of cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1756.

Centaurea bruguierana inhibits cell proliferation, causes cell cycle arrest, and induces apoptosis in human MCF-7 breast carcinoma cells.

Centaurea bruguierana, of the Asteraceae family, has a long history of use in traditional medicines for the treatment of various ailments. However, the anticancer activity and underlying mechanisms have not yet been assessed. The C. bruguierana was extracted with methanol and fractionated into four different fractions. Different cancer cells and one non-cancerous were used to examine the cytotoxic effects of these fractions using MTT assay. The most potent fraction, C. bruguierana ethyl acetate fraction (CB EtOAc), was explored for its effects on cell cycle progression and apoptosis induction by Hoechst staining and annexin V-PI double staining in MCF-7 cells. The expression of apoptosis-related genes was quantified by RT-PCR. Of all fractions, CB EtOAc was found to have the strongest antiproliferative activity (IC50 = 10μg/mL) against MCF-7 cells. The antiproliferative activity of the CB EtOAc fraction against MCF-7 was correlated with arrested of cell cycle in the G1 phase, nuclear fragmentation, and the exposure of phosphatidylserine. The induction of apoptosis by CB EtOAc in MCF-7 cells was also associated with an increase in the Bax/Bcl-2 ratio and higher expression of caspases. Overall, our results demonstrated that CB EtOAc showed apoptosis-inducing effects, suggesting that C. bruguierana may be a promising source for a novel chemotherapeutic agents for the treatment of breast cancer.

Synthesis, Antiproliferative and Cytotoxic Activities, DNA Binding Features and Molecular Docking Study of Novel Enamine Derivatives.

Novel enamine derivatives were synthesized from the reaction of lactone and chalcones and their antiproliferative and cytotoxic activities against six cancer cell lines (e. g., HeLa, HT29, A549, MCF7, PC3 and Hep3B) and one normal cell lines (e. g., FL) were investigated along with their mode of interactions with CT-DNA. Most of the enamine derivatives with IC50 values of 86-168 μM demonstrated much stronger antiproliferative activity than the starting molecules against the cancer cells. While, among the enamine derivatives, four compounds displayed higher cytotoxic potency than the control drugs (5-fluorouracil and cisplatin) against the Hep3B cell lines, these compounds did not exhibit any significant toxicity against normal cells, FL. The UV/VIS spectral data suggest that eight compounds cause hypochromism with a slight bathochromic shift (∼6 nm), indicating that they bind to the DNA by way of an intercalative or minor groove binding mode. The binding constants of the compounds are in the range of 0.1×103 M-1 -2.3×104 M-1 . The antiproliferative activity of studied enamine derivatives could possibly be due to their DNA binding as well as their cytotoxic properties. In addition to these assays, the chalcones and enamine derivatives were investigated by molecular docking to calculate the synergistic effect of antiproliferative activities against six human cancer cell lines.

Self-Assembled Supramolecular Micelles with pH-Responsive Properties for More Effective Cancer Chemotherapy.

pH-Responsive hydrogen-bonded supramolecular micelles, composed of a water-soluble poly(ethylene glycol) polymer with two terminal sextuple hydrogen bonding groups, can spontaneously organize in aqueous media to give well-defined, uniformly sized spherical micelles. The supramolecular micelles exhibit a number of unique physical characteristics, such as interesting amphiphilic behavior, desirable micellar size and nanospherical morphology, excellent biocompatibility, tailorable drug-loading capacities, and high structural stability in media containing serum or red blood cells. In addition, the drug release kinetics of drug-loaded micelles can be easily manipulated to achieve the desired release profile by regulating the environmental pH, thus these micelles are highly attractive candidates as an intelligent drug carrier system for cancer therapy. Cytotoxicity assays showed that the drug-loaded micelles induced pH-dependent intracellular drug release and exerted strong antiproliferative and cytotoxic activities toward cancer cells. Importantly, cellular uptake and flow cytometric analyses confirmed that a mildly acidic intracellular environment significantly increased cellular internalization of the drug-loaded micelles and subsequent drug release in the cytoplasm and nucleus of cancer cells, resulting in more effective induction of apoptotic cell death. Thus, this system may provide an efficient route toward achieving the fundamental properties and practical realization of pH-sensitive drug-delivery systems for chemotherapy.

The antiproliferative and antioxidant activities of the essential oils of Juniperus species from Turkey

AbstractThe present study aimed to determine the essential oil compositions of four different types of Juniperus species including Juniperus oxycedrus ssp oxycedrus L., Juniperus foetidissima Willd., Juniperus excelsa M. Bieb, and Juniperus communis L. with their antioxidant and antiproliferative activities. The antiproliferative activity of the essential oils was determined against HeLa (human cervix carcinoma) and C6 (rat brain tumor cell) cell lines by BrdU cell proliferation assay. The essential oils were tested for their total reducing power activity, DPPH (2,2'‐diphenyl‐1‐picrylhydrazyl) free radical scavenging activities, and hydrogen peroxide scavenging activities. The overall results of the study showed that the needles of Juniperus species have strong antiproliferative activities as cell selective against C6 cells.

Antioxidant and antimicrobial capacity of Lactifluus rugatus and its antiproliferative activity on A549 cells

In the present study, the antioxidant, antimicrobial potential and antiproliferative activity of Lactifluus rugatus mushroom were determined. Thus, extracts of the mushroom were obtained using a Soxhlet device. Antioxidant and oxidant potentials were determined using Rel Assay kits. Antimicrobial potential was tested on 9 microorganisms using the modified agar dilution method. MTT test was conducted on A549 cells to determine the anti-proliferative activity. As a result, high level of antioxidant activity was determined in L. rugatus. Furthermore, it was determined that the mushroom had antimicrobial properties on tested bacteria and fungi and strong anti-proliferative activity on A549 cells. In conclusion, it was considered that L. rugatus had pharmacological potential and it can be utilized as a natural pharmacological agent.

The Antitumor Activity of a Novel Fluorobenzamidine against Dimethylhydrazine- Induced Colorectal Cancer in Rats.

Colorectal cancer is among the leading causes of death worldwide. The incidence of deaths is expected to be 11.4 million in 2030. We aimed to evaluate the in vitro and in vivo antioxidant and antitumor activities of a novel Bithiophene- Fluorobenzamidine (BFB) against DMH-induced colorectal cancer in rats. The antiproliferative activity of BFB against HCT-116 colon cancer cells and apoptotic genes was assessed. In vivo study was also conducted in which 80 adult male rats were divided into 5 groups; control, BFB, and the other 3 groups were injected with DMH (20mg/kg, s.c., for 9 weeks). Group 4 was injected with 5 doses of cisplatin (2.5mg/kg, i.p over 21 weeks) and group 5 was injected with 3 doses/week of BFB (2.5mg/kg, i.p, for 21 weeks). BFB exhibited weak to moderate in vitro antioxidant activity. It had a strong antiproliferative activity with IC50 ~0.3µg/ml. BFB induced extrinsic apoptosis through the upregulation of FasL, TRAL, p53 and caspase-8, and intrinsic apoptosis through the downregulation of Bcl-2 and survivin. BFB decreased the tumor incidence, multiplicity and size and improved the decreased body weight. BFB also ameliorated the functions of kidney and liver and antioxidants deteriorated by DMH. BFB significantly improved the pathological changes caused by DMH in colon tissues. BFB showed a very promising antitumor activity against colorectal cancer induced by DMH in rats without causing hepato- or nephrotoxicity.

Mesomeric form of quaternary indoloquinazoline alkaloid and other constituents from the Cameroonian Rutaceae Araliopsis soyauxii Engl.

A mesomeric form of quaternary indoloquinazoline alkaloid, soyauxinium chloride (1) was obtained through the chemical investigation of stem bark and roots of Araliopsis soyauxii Engl. [syn. Vepris soyauxii (Engl.) Mziray] (Rutaceae) together with fifteen known compounds, including three furoquinoline alkaloids, three 2-quinolones, two limonoids, two triterpenes, two steroids, a coumarin, an acridone alkaloid, and a flavonoid glycoside. Their structures were established by comprehensive spectroscopic and spectrometric analyses (1D and 2D NMR, ESI-HR-MS) and by comparison with previously reported data. 13C NMR data of araliopsinine are also reported here for the first time. The isolated compounds were screened in vitro for their effects on the viability of two different human cancer cell lines, namely prostate PC-3 adenocarcinoma cells and colorectal HT-29 adenocarcinoma cells. However, none of the tested compounds exhibited strong anti-proliferative or cytotoxic activities, to either prostate PC-3 cells or colon HT-29 cells. At 100 μM, the furoquinoline maculine showed a slightly increased anti-proliferative effect, however, exclusively on HT-29 cells. The chemotaxonomic significance of the isolated compounds has also been discussed.

Synthesis, Antiproliferative Activity and Molecular Docking Studies of Novel Doubly Modified Colchicine Amides and Sulfonamides as Anticancer Agents.

Colchicine is a well-known compound with strong antiproliferative activity that has had limited use in chemotherapy because of its toxicity. In order to create more potent anticancer agents, a series of novel colchicine derivatives have been obtained by simultaneous modification at C7 (amides and sulfonamides) and at C10 (methylamino group) positions and characterized by spectroscopic methods. All the synthesized compounds have been tested in vitro to evaluate their cytotoxicity toward A549, MCF-7, LoVo, LoVo/DX and BALB/3T3 cell lines. Additionally, the activity of the studied compounds was investigated using computational methods involving molecular docking of the colchicine derivatives to β-tubulin. The majority of the obtained derivatives exhibited higher cytotoxicity than colchicine, doxorubicin or cisplatin against tested cancer cell lines. Furthermore, molecular modeling studies of the obtained compounds revealed their possible binding modes into the colchicine binding site of tubulin.

Insights about the structure of farnesyl diphosphate synthase (FPPS) and the activity of bisphosphonates on the proliferation and ultrastructure of Leishmania and Giardia

BackgroundThe enzyme farnesyl diphosphate synthase (FPPS) is positioned in the intersection of different sterol biosynthesis pathways such as those producing isoprenoids, dolichols and ergosterol. FPPS is ubiquitous in eukaryotes and is inhibited by nitrogen-containing bisphosphonates (N-BP). N-BP activity and the mechanisms of cell death as well as damage to the ultrastructure due to N-BP has not yet been investigated in Leishmania infantum and Giardia. Thus, we evaluated the effect of N-BP on cell viability and ultrastructure and then performed structural modelling and phylogenetic analysis on the FPPS enzymes of Leishmania and Giardia.MethodsWe performed multiple sequence alignment with MAFFT, phylogenetic analysis with MEGA7, and 3D structural modelling for FPPS with Modeller 9.18 and on I-Tasser server. We performed concentration curves with N-BP in Leishmania promastigotes and Giardia trophozoites to estimate the IC50via the MTS/PMS viability method. The ultrastructure was evaluated by transmission electron microscopy, and the mechanism of cell death by flow cytometry.ResultsThe nitrogen-containing bisphosphonate risedronate had stronger anti-proliferative activity in Leishmania compared to other N-BPs with an IC50 of 13.8 µM, followed by ibandronate and alendronate with IC50 values of 85.1 µM and 112.2 µM, respectively. The effect of N-BPs was much lower on trophozoites of Giardia than Leishmania (IC50 of 311 µM for risedronate). Giardia treated with N-BP displayed concentric membranes around the nucleus and nuclear pyknosis. Leishmania had mitochondrial swelling, myelin figures, double membranes, and plasma membrane blebbing. The same population labelled with annexin-V and 7-AAD had a loss of membrane potential (TMRE), indicative of apoptosis. Multiple sequence alignments and structural alignments of FPPS proteins showed that Giardia and Leishmania FPPS display low amino acid identity but possess the conserved aspartate-rich motifs.ConclusionsGiardia and Leishmania FPPS enzymes are phylogenetically distant but display conserved protein signatures. The N-BPs effect on FPPS was more pronounced in Leishmania than Giardia. This might be due to general differences in metabolism and differences in the FPPS catalytic site.

Antitumor activity of a novel oral signal transducer and activator of transcription 3 inhibitor YHO-1701.

The signal transducer and activator of transcription 3 (STAT3) signaling pathway is a key mediator of cancer cell proliferation, survival and invasion. Aberrant STAT3 has been demonstrated in various malignant cancers. YHO‐1701 is a novel quinolinecarboxamide derivative generated from STX‐0119. Here, we examined the effect of YHO‐1701 on STAT3 and evaluated antitumor activity of YHO‐1701 as a single agent and in combination. YHO‐1701 inhibited STAT3‐SH2 binding to phospho‐Tyr peptide selectively and more potently than STX‐0119 in biochemical assays. Molecular docking studies with STAT3 suggested more stable interaction of YHO‐1701 with the SH2 domain. YHO‐1701 exhibited approximately 10‐fold stronger activity than STX‐0119 in abrogating the STAT3 signaling pathway of human oral cancer cell line SAS. YHO‐1701 also blocked multi‐step events by inhibiting STAT3 dimerization and suppressed STAT3 promoter activity. As expected, YHO‐1701 exerted strong antiproliferative activity against human cancer cell lines addicted to STAT3 signaling. Orally administered YHO‐1701 showed statistically significant antitumor effects with long exposure to high levels of YHO‐1701 at tumor sites in SAS xenograft models. Moreover, combination regimen with sorafenib led to significantly stronger antitumor activity. In addition, the suppression level of survivin (a downstream target) was superior for the combination as compared with monotherapy groups within tumor tissues. Thus, YHO‐1701 had a favorable specificity for STAT3 and pharmacokinetics after oral treatment; it also contributed to the enhanced antitumor activity of sorafenib. The evidence presented here provides justification using for this approach in future clinical settings.