Leukemia Cell Line K562 Research Articles

A heparan-sulfate-bearing syndecan-1 glycoform is a distinct surface marker for intra-tumoral myeloid-derived suppressor cells

SummaryMyeloid-derived suppressor cells (MDSCs) infiltrate cancer tissue, promote tumor growth, and are associated with resistance to cancer therapies. However, there is no practical approach available to distinguish MDSCs from mature counterparts inside tumors. Here, we show that a recently isolated thioaptamer probe (T1) binds to MDSC subsets in colorectal and pancreatic tumors with high specificity. Whole transcriptome and functional analysis revealed that T1-binding cells contain polymorphonuclear (PMN)-MDSCs characterized by several immunosuppression pathways, ROS production, and T cell suppression activity, whereas T1-non-binding PMNs were mature and nonsuppressive. We identified syndecan-1 as the T1-interacting protein on MDSCs and chronic myelogenous leukemia K562 cell line. Heparan sulfate chains were essential in T1-binding. Inside tumors PMN-MDSCs expressed heparan sulfate biogenesis enzymes at higher levels. Tumor-cell-derived soluble factor(s) enhanced MDSCs' affinity for T1. Overall, we uncovered heparan-sulfate-dependent MDSC modulation in the tumor microenvironment and identified T1 as tool preferentially targeting tumor-promoting myeloid cell subsets.

Investigation of the Mechanisms of Cytotoxic Activity of 1,3-Disubstituted Thiourea Derivatives.

Substituted thiourea derivatives possess confirmed cytotoxic activity towards cancer but also normal cells. To develop new selective antitumor agents, a series of 3-(trifluoromethyl)phenylthiourea analogs were synthesized, and their cytotoxicity was evaluated in vitro against the cell line panel. Compounds 1–5, 8, and 9 were highly cytotoxic against human colon (SW480, SW620) and prostate (PC3) cancer cells, and leukemia K-562 cell lines (IC50 ≤ 10 µM), with favorable selectivity over normal HaCaT cells. The derivatives exerted better growth inhibitory profiles towards selected tumor cells than the reference cisplatin. Compounds incorporating 3,4-dichloro- (2) and 4-CF3-phenyl (8) substituents displayed the highest activity (IC50 from 1.5 to 8.9 µM). The mechanisms of cytotoxic action of the most effective thioureas 1–3, 8, and 9 were studied, including the trypan blue exclusion test of cell viability, interleukin-6, and apoptosis assessments. Compounds reduced all cancerous cell numbers (especially SW480 and SW620) by 20–93%. Derivatives 2 and 8 diminished the viability of SW620 cells by 45–58%. Thioureas 1, 2, and 8 exerted strong pro-apoptotic activity. Compound 2 induced late apoptosis in both colon cancer cell lines (95–99%) and in K-562 cells (73%). All derivatives acted as inhibitors of IL-6 levels in both SW480 and SW620 cells, decreasing its secretion by 23–63%.

Anticancer Activity of Periplanetasin-5, an Antimicrobial Peptide from the Cockroach Periplaneta americana.

Cockroaches live in places where various pathogens exist and thus are more likely to use antimicrobial compounds to defend against pathogen intrusions. We previously performed an in silico analysis of the Periplaneta americana transcriptome and detected periplanetasin-5 using an in silico antimicrobial peptide prediction method. In this study, we investigated whether periplanetasin-5 has anticancer activity against the human leukemia cell line K562. Cell growth and survival of K562 cells treated with periplanetasin-5 were decreased in a dose-dependent manner. By using flow cytometric analysis, acridine orange/ethidium bromide (AO/EB) staining and DNA fragmentation, we found that periplanetasin-5 induced apoptotic and necrotic cell death in leukemia cells. In addition, these events were associated with increased levels of the pro-apoptotic proteins Fas and cytochrome c and reduced levels of the anti-apoptotic protein Bcl-2. Periplanetasin-5 induces the cleavage of pro-caspase-9, pro-caspase-8, pro-caspase-3, and poly (ADP-ribose) polymerase (PARP). The above data suggest that periplanetasin-5 induces apoptosis via both the intrinsic and extrinsic pathways. Moreover, caspase-related apoptosis was further confirmed by using the caspase inhibitor carbobenzoxy-valyl-alanyl-aspartyl-[O-methyl]- fluoromethylketone (Z-VAD-FMK), which reversed the periplanetasin-5-induced reduction in cell viability. In conclusion, periplanetasin-5 caused apoptosis in leukemia cells, suggesting its potential utility as an anticancer therapeutic agent.

Synthesis, molecular docking, and biological activity of thioether derived from juglone in preclinical models of chronic myeloid leukemia

In this work, 16 new thio-1,4-naphthoquinones were synthesized, and their antiproliferative effects against tumor cell lines SK-MEL-19, AGP-01, ACP-02, HL-60, K-562, K-562-Lucena-1, FEPS, and non-neoplastic human fibroblast MRC-5, were examined. The compounds were selective active against leukemia cell lines. Based on the screening results for cytotoxic activity, naphthoquinone 11a showed higher cytotoxicity on the chemoresistant leukemia (FEPS) cell line when compared to the chemosensitive (K-562) cell line. Moreover, naphthoquinone 11a presented excellent ADME/T and did not violate Lipinski’s rule of five, indicating good oral absorption. Target prediction revealed DNA topoisomerase I (TOP1) as a possible target of 11a. The molecular docking prediction showed an − 11.94 kcal/mol binding affinity interaction of 11a with TOP1, involving three hydrogen bonds to ARG364, A113, and G11 from the active site of the enzyme. In addition, naphthoquinone 11a significantly suppressed the expression of the TOP1 gene in K-562 and FEPS leukemia cell lines. The naphthoquinone 11a induced significant changes in cell morphology, demonstrating cell and nuclear shrinkage, blebbing formation as well and fragmentation of the cell into apoptotic bodies. Thus, 11a could be a drug that leads to a new set of TOP1 major inhibitors. In summary, the present study showed a cytotoxic effect of 11a against chemoresistant and chemosensitive leukemia cell lines with TOP1 as a possible target.

Endogenous NO-releasing Carbon Nanodots for Tumor-specific Gas Therapy

Carbon nanodots based on L-arginine (L-Arg) were developed for enhanced nitric oxide (NO) gas therapy for cancer. The L-Arg-based carbon nanodots (Arg-dots) produced high levels of NO in the tumor environment rich in endogenous H2O2. In vitro cell experiments revealed that the Arg-dots could kill tumor cells (including human breast cancer cell line MCF-7, female gastric cancer cell line BGC-823, male lung cancer cell line A549, and female leukemic cell line K562) but did not affect the activity of normal cells (human normal lung epithelial cell line BEAS-2B). The Arg-dots produced twice the amount of NO for an equivalent amount of L-Arg. Theoretical calculations showed that the carbonization structure of the Arg-dots promoted significantly more electrons toward the guanidinium groups of L-Arg and boosted the adsorption of H2O2 molecules. In vitro and in vivo investigations confirmed that the Arg-dots reduced the multidrug resistance (MDR) effect of the tumor cells (MCF-7/ADR cells) and produced a combined antitumor efficacy with traditional chemotherapeutic drugs (adriamycin [ADR]). The fluorescence property (quantum yield, 6.88%) allows the Arg-dots to be used as a suitable fluorescent probe for fluorescence imaging of tumor cells. The ultra-small size of the Arg-dots (diameter: ca. 2.5 nm) enables them not only to penetrate deep tumors and provide enhanced antitumor activity but also to be removed through kidney filtration and have a renal clearance property. Statement of significanceNitric oxide (NO), which serves as a biological messenger, can be used in gas therapy for cancer. The development of a safe and efficient NO cancer therapy is, however, challenging because of the low NO release amount and poor tumor specificity of most NO donors. Many efforts have been made to overcome these drawbacks, but solving both these limitations through a single approach has been seldom achieved. In the present work, carbon nanodots (Arg-dots) from L-arginine were used for gas therapy of cancer. The Arg-dots produced NO in the H2O2-rich tumor environment. Theoretical calculations were consistent with the mechanism of enhanced NO release amount. The Arg-dots also reduced the multidrug resistance effect in cancer chemotherapy. In vivo and in vitro toxicity assessments confirmed that the Arg-dots have excellent biosafety.

Design, synthesis, molecular docking and biological evaluation of novel 1,5-diarylpyrazole-N,O-dimethyl hydroxamate derivatives as antiproliferative agents.

A series of novel hybrid of 1,5-diarylpyrazole-N,O-dimethylhydroxamate derivatives were designed and synthesised in synthetically acceptable yields. All the new synthesized compounds were biologically evaluated for their in vitro cytotoxicity against a panel of five cell lines namely human colorectal adenocarcinoma cell line DLD1, human cervical cancer cell line Hela, human leukemia cell line K562, human pancreatic cancer cell line Suit-2 and human hepatocellular carcinoma cell line HepG2. Compound 7a showed a significant cytotoxicity against Hela cell line with IC50 value of 16 µM and a good cytotoxicity against DLD1 and HepG2 with IC50 values of 69.9 µM and 78.8µM. Also, compound 7a displayed a potent EGFR inhibitory activity with IC50= 4.00 µM, which was comparable to positive reference drug sorafenib (IC50 = 3.5 µM). Moreover, in-silico studies showed that compound 7a has excellent binding affinity to the active site of EGFR with binding score better than a multitarget kinase drug sorafenib and good binding affinity to JNK-2, which explains the anticancer activity of compound 7a.

HPRep: Quantifying Reproducibility in HiChIP and PLAC-Seq Datasets

HiChIP and PLAC-Seq are emerging technologies for studying genome-wide long-range chromatin interactions mediated by the protein of interest, enabling more sensitive and cost-efficient interrogation of protein-centric chromatin conformation. However, due to the unbalanced read distribution introduced by protein immunoprecipitation, existing reproducibility measures developed for Hi-C data are not appropriate for the analysis of HiChIP and PLAC-Seq data. Here, we present HPRep, a stratified and weighted correlation metric derived from normalized contact counts, to quantify reproducibility in HiChIP and PLAC-Seq data. We applied HPRep to multiple real datasets and demonstrate that HPRep outperforms existing reproducibility measures developed for Hi-C data. Specifically, we applied HPRep to H3K4me3 PLAC-Seq data from mouse embryonic stem cells and mouse brain tissues as well as H3K27ac HiChIP data from human lymphoblastoid cell line GM12878 and leukemia cell line K562, showing that HPRep can more clearly separate among pseudo-replicates, real replicates, and non-replicates. Furthermore, in an H3K4me3 PLAC-Seq dataset consisting of 11 samples from four human brain cell types, HPRep demonstrated the expected clustering of data that could not be achieved by existing methods developed for Hi-C data, highlighting the need for a reproducibility metric tailored to HiChIP and PLAC-Seq data.

Hijacking TYRO3 from Tumor Cells via Trogocytosis Enhances NK-cell Effector Functions and Proliferation.

Trogocytosis is a fast, cell-cell contact-dependent uptake of membrane patches and associated molecules by one cell from another. Here, we report our investigation of trogocytosis of TYRO3, a cell membrane protein, from tumor target cells to natural killer (NK) cells and the associated functional consequences for NK cells. We found that although NK cells did not express endogenous TYRO3 on the cell surface, activated NK cells rapidly acquired TYRO3 from tumor cells via trogocytosis in vitro and in vivo. NK cells that acquired TYRO3, which we termed TYRO3+ NK cells, had significantly enhanced cytotoxicity and IFNγ production as well as higher expression of some activated surface markers compared with TYRO3- NK cells. Furthermore, the activation status of NK cells and TYRO3 expression levels on donor cells, either endogenous or ectopic, positively correlated with trogocytosis levels. When the antigen-presenting cell (APC) K562 leukemia cell line, a feeder cell line to expand NK cells, overexpressed TYRO3, TYRO3 was transferred to NK cells via trogocytosis, which improved NK-cell proliferation ex vivo. This provides a strategy to manufacture NK cells or their engineered counterparts, such as chimeric antigen receptor NK cells, for the treatment of cancer or infectious diseases.

Selective Chemical Activation of Piezo1 in Leukemia Cell Membrane: Single Channel Analysis.

Piezo1/2 are mechanosensitive calcium-permeable channels that can be activated by various modes of membrane deformation. The identification of the small molecule Yoda1, a synthetic Piezo1 agonist, revealed the possibility of chemical activation of the channel. Stimulating effects of Yoda1 on Piezo1 have been mainly documented using over-expressing cellular systems or channel proteins incorporated in artificial lipid bilayers. However, the activating effect of Yoda1 on native Piezo1 channels in the plasma membrane of living cells remains generally undefined, despite the increasing number of studies in which the agonist is utilized as a functional tool to reveal the contribution of Piezo1 to cellular reactions. In the current study, we used the human myeloid leukemia K562 cell line as a suitable model to examine chemically induced Piezo1 activity with the use of the patch-clamp technique in various specific modes. The functional expression of Piezo1 in leukemia cells was evidenced using a combinative approach, including single channel patch-clamp measurements. Utilizing our established single-current whole-cell assay on K562 cells, we have shown, for the first time, the selective real-time chemical activation of endogenously expressed Piezo1. Extracellular application of 0.5–1 µM Yoda1 effectively stimulated single Piezo1 currents in the cell membrane.

Evaluation of the Apoptotic Effects of the Humic Acid Treatment on Chronic Myeloid Leukemia Cell Line K562

Evaluation of the Apoptotic Effects of the Humic Acid Treatment on Chronic Myeloid Leukemia Cell Line K562

The IL15 Superagonist Complex ALT-803 Potently Enhances the Proliferative Capacity and Activity of in Vitro Expanded Natural Killer Cells

IntroductionWe previously reported on the treatment of 8 relapsing high-risk multiple myeloma (HRMM) patients with ex vivo activated/expanded NK cells (ENKs). We demonstrated that interleukin-2 (IL2) provided suboptimal cytokine support post adoptive transfer of ENKs. Aiming to improve upon prior data we hypothesize that the novel IL15 superagonist complex ALT-803 will provide superior support compared to IL2 and enhance ENK activity, proliferation and persistence.MethodsTo compare the activity of IL2 and ALT-803 on ENKs, we performed long-term in vitro culture studies. Analogous to the 8-day clinical production method, healthy donor (HD) peripheral blood mononuclear cells (PBMCs) were first co-cultured with the leukemic cell line K562 modified to express both membrane-bound IL15 and the costimulatory molecule 4-1BBL, and high-dose IL2. We deliberately chose to maintain IL2 in the expansion method rather than substituting ALT-803 because our FDA-approved GMP-grade expansion was validated using IL2. On expansion Day 8 (the day clinical ENK products are infused), the ENKs were either maintained at high-dose (300U/mL) IL2, or otherwise cultured at low-dose (20U/mL) IL2 or 35ng/mL ALT-803, in all conditions without K562 stimulator cells. Proliferation (fold-change from baseline) was measured on Days 14, 21, and 28, and expression of key activating and inhibitory markers was assessed via flow cytometry. Relative cytolytic ability was determined via 4-hour chromium (Cr)-release assays against K562 and the MM cell lines OPM2, JJN3, and U266.ResultsProliferation of ALT-803-ENKs was superior to both IL2-ENK conditions at all assessed time points; on Day 28, fold-expansion of ALT-803-ENKs was 753, versus 156- and 557-fold for ENKs maintained in 20U or 300U/mL IL2, respectively, Figure 1A. Immunophenotyping studies demonstrated significant differences between ENKs cultured in 20U/mL IL2 versus ALT-803-treated ENKs, including activation (CD26, CD69, DNAM1, NKp30) and functional (CD16, perforin, granzyme, TRAIL) molecules. ALT-803-treated ENKs maintained an activated phenotype, whereas IL2 ENKs (20U/mL) exhibited reduced expression of several markers by Day 14, with further decreases noted on Days 21 and 28. Representative examples are depicted in Figure 1B. Morphologically, IL2-ENKs acquired apoptotic features after extended culture, whereas ALT-803-ENKs did not. Though cytolytic ability was variable on Days 14 and 21, the activity of ALT-803-ENKs exceeded that of IL2-ENKs (20U/mL) against K562, OPM2, JJN3, and U266 cell lines on Day 28. High-dose IL2-ENKs exhibited a similar phenotype and cytolytic ability compared to ALT-803-ENKs.ConclusionsWe compared clinically-relevant doses of IL2 and ALT-803 to determine whether ALT-803 is superior at maintaining ENK activity and proliferative capacity. ALT-803 ENKs exhibited robust proliferation through Day 28 and sustained expression of key activation and functional markers, highlighting the superiority of ALT-803 in this setting. After four weeks of continuous culture, ALT-803-ENKs maintained greater cytolytic ability against MM cell lines. Though high-dose IL2 is capable of sustaining ENK activation state in vitro, this dose is not achievable in humans. Unlike IL2, ALT-803 does not induce expansion of T regulatory cells, and has a more favorable toxicity profile. Importantly, ALT-803 stimulated and maintained expression of CD16, indicating that it would be well-suited to pair with monoclonal antibodies for the support of antibody-dependent cellular cytotoxicity. Further studies are in progress to study the effects of ALT-803 on ENKs in the presence of suppressive cytokines/cells to determine if ALT-803 is able to overcome the effects of the tumor microenvironment. [Display omitted] DisclosuresWong:Altor BioScience: Employment, Equity Ownership. Jeng:Altor Bioscience: Employment, Equity Ownership. Shrestha:Altor Bioscience: Employment, Equity Ownership. Davies:Janssen: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Morgan:Bristol Myers: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding.

The WASP P460S Mutation Causes a New Phenotype of WASP Mutations Related Disorder: X-Linked Pancytopenia

Mutations of the Wiskott-Aldrich Syndrome Protein (WASP) are responsible for a rare and severe disease: Wiskott-Aldrich Syndrome (WAS), including classic Wiskott-Aldrich Syndrome (WAS), X-linked thrombocytopenia (XLT), and congenital X-linked neutropenia (XLN). Classic WAS patients present typical WAS manifestation: eczema, thrombocytopenia, small platelet and recurrent infection, while XLT patients present thrombocytopenia, and XLN patients present congenital neutropenia. Bone marrow failure (BMF) is a series diseases characterized by pancytopenia in peripheral-blood(PB), different degree of bone marrow hypocellularity. In this study, we present two unrelated boys with pancytopenia who were admitted to our hospital on account of declining blood cells and different degree of hematopoietic failure. We identified a new WAS gene mutation C1378T inducing the WASP P460S mutation in both penitents by the second generation sequencing. Furthermore, one case developed T cell acute lymphoblastic leukemia (T-ALL) after severe pancytopenia recovered for 4 years and relapsed in mediastinum transplanted with cord blood for 1 year, another case recovered after haploidentical transplantation and kept stable for 1 year. To date, the role of WAS gene mutation in aplastic anemia-like hematopoietic failure remains unknown. We further verified WASP P460S mutation in these two patients by Sanger sequencing. In patient's PB cells, normal expression level of total WASP proteins was detected. This notion was different from general WASP deficiency classic WAS or XLT patients. To test the function of WASP P460S mutation in pancytopenia, we examined the effect of WASP P460S mutation on cell proliferation. Human myelogenous leukemia K562 cell line, which lacks endogenous WASP, was transfected with lentivirus vectors carrying mutant or wild type of WAS gene. We found that the cells expressing WASP P460S grew significantly slower than the cells expressing the wild type. Moreover, actin polymerization assay showed that increased actin polymerization function in WASP P460S mutation compared with wild type. In addition, P460S mutation had no obvious effect on Daunorubicin-induced apoptosis response. Our findings revealed that the WASP P460S mutation played a role in the inhibition of cell proliferation and actin polymerization which may lead to a new phenotype for WASP mutation related X-linked pancytopenia. DisclosuresNo relevant conflicts of interest to declare.

Histone Deacetylase Inhibitor Depsipeptide (FK228) Induces Apoptosis in Leukemic Cells by Facilitating Mitochondrial Translocation of Bax, Which Is Enhanced by Proteasome Inhibitor Bortezomib.

Histone deacetylase (HDAC) inhibitors are a promising candidate for molecular-targeted therapy for leukemia. In this study, we investigated the mechanisms of cytotoxic effects of depsipeptide (FK228), one of the most effective HDAC inhibitors against leukemia, using human myeloid leukemic cell lines HL-60 and K562. We found that FK228 activated caspase-9 and a subsequent caspase cascade by perturbing the mitochondrial membrane to release cytochrome c, which was almost completely blocked by overexpression of Bcl-2. The mitochondrial damage was caused by the translocation of Bax but not other proapoptotic Bcl-2 family proteins to the mitochondria. FK228 did not affect the interaction between Bax and Bax-adaptor proteins such as 14–3–3 theta and Ku70. FK228-induced apoptosis and mitochondrial translocation of Bax were markedly enhanced by the proteasome inhibitor bortezomib. The synergistic action of FK228 and Bortezomib was at least partly mediated through conformational changes of Bax, which facilitate its translocation to the mitochondria. These results suggest that the combination of HDAC inhibitors and proteasome inhibitors is useful for the treatment of leukemia especially in the context of molecular-targeted therapy. The status of Bcl-2 and Bax may influence the sensitivity of tumors to this combination, and thus, can be a target of further therapeutic intervention.

S100 Calcium-Binding Protein P Secreted from Megakaryocytes Promotes Osteoclast Maturation.

Megakaryocytes (MKs) differentiate from hematopoietic stem cells and produce platelets at the final stage of differentiation. MKs directly interact with bone cells during bone remodeling. However, whether MKs are involved in regulating bone metabolism through indirect regulatory effects on bone cells is unclear. Here, we observed increased osteoclast differentiation of bone marrow-derived macrophages (BMMs) cultured in MK-cultured conditioned medium (MK CM), suggesting that this medium contains factors secreted from MKs that affect osteoclastogenesis. To identify the MK-secreted factor, DNA microarray analysis of the human leukemia cell line K562 and MKs was performed, and S100 calcium-binding protein P (S100P) was selected as a candidate gene affecting osteoclast differentiation. S100P was more highly expressed in MKs than in K562 cells, and showed higher levels in MK CM than in K562-cultured conditioned medium. In BMMs cultured in the presence of recombinant human S100P protein, osteoclast differentiation was promoted and marker gene expression was increased. The resorption area was significantly larger in S100P protein-treated osteoclasts, demonstrating enhanced resorption activity. Overall, S100P secreted from MKs promotes osteoclast differentiation and resorption activity, suggesting that MKs indirectly regulate osteoclast differentiation and activity through the paracrine action of S100P.

DNA binding ability and cytotoxicity, cell cycle arrest and apoptosis inducing properties of a benzochromene derivative against K562 human leukemia cells

Chromene and its derivatives are generally spread in nature. Heterocylic-based compounds like chromenes have displayed pharmacological activities. Chromene derivatives are critical due to some biological features such as anticancer activity. CML, chronic myelogenous leukemia, is a fatal malignancy determined by resistance to apoptosis and contains the Philadelphia chromosome. Induction of apoptosis is one of the main approaches in cancer therapy. In this research, benzochromene derivative, 2-amino-4-(4-methoxy phenyl)-4H-benzochromene-3-carbonitrile (4-MC) was tested for cytotoxic and apoptotic induction activities in the human leukemic K562 cell line. The MTT growth inhibition assay was used to determine the cellular growth and survival. Moreover, the binding attribute of 4-MC with double helix DNA was assessed by some spectroscopic and viscosity measurement, and also for docking analysis. 4-MC exhibited good cytotoxicity on K562 cell line and the IC50 value was calculated to be 30 µM. Furthermore, the mechanisms of apoptosis induction were determined morphologically by fluorescence dual staining with acridine orange and ethidium bromide and cell cycle analysis was based on DNA content, as well as the presence of phosphatidyl serine on the outside of the cells by the flow cytometric method. The results showed that 4-MC had potent cytotoxic activity via sub-G1 cell cycle arrest and induction of apoptosis. The experimental and simulation studies reported that 4-MC binds to ctDNA through groove binding mode with the binding constant (K b) of 2.5 × 103 M−1. These data represent a considerable anticancer potential of 4-MC and could be suggested for further pharmacological studies.

Stereochemistries and Biological Properties of Oligomycin A Diels-Alder Adducts.

Oligomycin A is a potent antibiotic and antitumor agent. However, its applications are restricted by its high toxicity and low bioavailability. In this study, we obtained Oligomycin A Diels-Alder adducts with benzoquinone and N-benzylmaleimide and determined their absolute configurations by combining 1H and ROESY NMR data with molecular mechanics conformational analysis and quantum chemical reaction modeling. The latter showed that adduct stereochemistry is controlled by hydrogen bonding of the Oligomycin A side-chain isopropanol moiety with the carbonyl group of the dienophile. Biological studies showed that the Diels-Alder modification of the Oligomycin A diene system resulted in a complex antiproliferative potential pattern. The synthesized adducts were determined to be more active against the triple-negative (ERα, PR, and HER2 negative) breast cancer cell line MDA-MB-231 and lung carcinoma cell line A-549 compared to Oligomycin A. Meanwhile, Oligomycin A was more potent against myeloid leukemia cell line K-562 and breast carcinoma cell line MCF-7 than its derivatives. Thus, modification of the diene moiety of Oligomycin A is a promising strategy for developing novel antitumor agents based on its scaffold.

Dispirooxindole-pyrrolothiazoles: Synthesis, anti-cancer activity, molecular docking and green chemistry metrics evaluation

A modest library of a set of dispirooxindole-pyrrolothiazole derivatives 5a–n has been synthesized through multicomponent technique employing 1,3-dipolar cycloaddition reaction of azomethine ylide with novel dipolarophiles, 2,6-di (arylmethylidene) -4-methylcyclohexanones 4a–n without any catalyst. The reaction provides simple and efficient access to synthetically useful and biologically important dispirooxindole-pyrrolothiazoles in high yield (86–98%) with high degree of stereo-, regio-, and chemo-selectivities. All the synthesized compounds were characterized using popular spectral methods like IR, 1H NMR, 13C NMR and 2D NMR techniques. Further, the molecular structure of 5a was confirmed by single crystal XRD. The synthesized compounds were subjected to cytotoxicity evaluation using K562-leukemia cell line. Compound 5 k has been found to be an effective compound of this class in targeting K562-leukemia cell with IC50 value of 13.28 ± 0.11 µg/ml. From the molecular docking data, it is realized that these compounds 5a–n showed a binding energy between -8.1 and -10.8 kcal/mol and thereby inhibit Tyrosine Kinases. Smaller E-factor (0.13), high atom-economy (89.74%), percentage yield (98.00%), reaction mass efficiency (88.43%), and carbon efficiency (96.97%) are successful achieved for compound 5j.

Urolithin A and B Alter Cellular Metabolism and Induce Metabolites Associated with Apoptosis in Leukemic Cells.

Leukemia is persistently a significant cause of illness and mortality worldwide. Urolithins, metabolites of ellagic acid and ellagitannins produced by gut microbiota, showed better bioactive compounds liable for the health benefits exerted by ellagic acid and ellagitannins containing pomegranate and walnuts. Here, we assessed the potential antileukemic activities of both urolithin A and urolithin B. Results showed that both urolithin A and B significantly inhibited the proliferation of leukemic cell lines Jurkat and K562, among which urolithin A showed the more prominent antiproliferative capability. Further, urolithin treatment alters leukemic cell metabolism, as evidenced by increased metabolic rate and notable changes in glutamine metabolism, one-carbon metabolism, and lipid metabolism. Next, we evidenced that both urolithins equally promoted apoptosis in leukemic cell lines. Based on these observations, we concluded that both urolithin A and B alter leukemic cell metabolome, resulting in a halt of proliferation, followed by apoptosis. The data can be used for designing new combinational therapies to eradicate leukemic cells.

Synthesis and bioactivity studies of covalent inhibitors derived from (-)-Chaetominine

We reported herein the synthesis and bioactivity studies of compounds derived from the natural product (-)-Chaetominine (6). The key feature of these compounds is the incorporation of electrophilic groups that are capable of forming covalent bonds with the cysteine or threonine residues of cellular proteins. The cell growth inhibition activities of these derivatives of 6 were tested in four cancer cell lines, i.e. a leukemia cell line K562, a multiple myeloma cell line MM1.S, an acute myeloid leukemia cell line MV4-11, and a colon cancer cell line RKO. The data show that cellular growth inhibition IC50 values of 29, an acrylamide-containing molecule, are 9-17 folds more potent than that of 6, while other acrylamide-containing compounds are much less potent, suggesting 29 might have covalent interactions with cellular target proteins. Collectively, incorporation of an acrylamide moiety into 6 is a good strategy to improve its cell growth inhibition activity in cancer cell lines.

Anti-chronic myeloid leukemia activity and quantitative structure-activity relationship of novel thiazole aminobenzamide derivatives

The anti-chronic myeloid leukemia activity of thiazole aminobenzamide derivatives in vitro was tested by a methanethiosulfonate (MTS)-based viability assay method, and the result showed that some compounds exhibited good inhibitory activities against human chronic myeloid leukemia cell line K562, imatinib-resistant strain K562/R and T135I mutant cell line BaF3-ABL-BCR-T315I. Comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) methods were used to analyze the relationship between the structure of thiazole aminobenzamide derivatives and the inhibition of K562/R cell activity. In CoMFA, Q2 was 0.899 and R2 was 0.963; in CoMSIA, Q2 and R2 were 0.840 and 0.903, respectively. These data indicated that the selected test set showed suitable external predictive ability. Combined with the contour map results, we further analyzed the three-dimensional quantitative structure (3D-QSAR) model. The results demonstrated that in the backbone of the thiazole aminobenzamide derivative, the substitution of a small group at R1 position, or the introduction of a hydrophilic group at R2 position, or the introduction of a large-volume amino acid at R3 position may be beneficial to improve the anti-CML activity of the compound.