Mitochondrial Functionality Is Regulated by Alkylphospholipids in Human Colon Cancer Cells.

Alkylphospholipids (APLs) have been studied as anticancer drugs that interfere with biological membranes without targeting DNA. Although their mechanism of action is not fully elucidated yet, it is known that they disrupt the intracellular trafficking of cholesterol and its metabolism. Here, we analyzed whether APLs could also interfere with mitochondrial function. For this purpose, we used HT29 colorectal cancer cells, derived from a primary tumor, and SW620 colorectal cancer cells, derived from a metastasis site. After treatment with the APLs miltefosine and perifosine, we analyzed various mitochondrial parameters, including mitochondrial mass, cardiolipin content, mitochondrial membrane potential, H2O2 production, the levels of oxidative phosphorylation (OXPHOS) complexes, metabolic enzymes activity, the oxygen consumption rate, and the levels of apoptosis and autophagy markers. APLs, especially perifosine, increased mitochondrial mass while OXPHOS complexes levels were decreased without affecting the total oxygen consumption rate. Additionally, we observed an increase in pyruvate dehydrogenase (PDH) and isocitrate dehydrogenase (IDH) levels and a decrease in lactate dehydrogenase (LDH) activity, suggesting a metabolic rewiring induced by perifosine. These alterations led to higher mitochondrial membrane potential, which was potentiated by decreased uncoupling protein 2 (UCP2) levels and increased reactive oxygen species (ROS) production. Consequently, perifosine induced an imbalance in mitochondrial function, resulting in higher ROS production that ultimately impacted cellular viability.

Embedding Biomimetic Magnetic Nanoparticles Coupled with Peptide AS-48 into PLGA to Treat Intracellular Pathogens.

Among the strategies employed to overcome the development of multidrug-resistant bacteria, directed chemotherapy combined with local therapies (e.g., magnetic hyperthermia) has gained great interest. A nano-assembly coupling the antimicrobial peptide AS-48 to biomimetic magnetic nanoparticles (AS-48-BMNPs) was demonstrated to have potent bactericidal effects on both Gram-positive and Gram-negative bacteria when the antimicrobial activity of the peptide was combined with magnetic hyperthermia. Nevertheless, intracellular pathogens remain challenging due to the difficulty of the drug reaching the bacterium. Thus, improving the cellular uptake of the nanocarrier is crucial for the success of the treatment. In the present study, we demonstrate the embedding cellular uptake of the original nano-assembly into THP-1, reducing the toxicity of AS-48 toward healthy THP-1 cells. We optimized the design of PLGA[AS-48-BMNPs] in terms of size, colloidal stability, and hyperthermia activity (either magnetic or photothermal). The stability of the nano-formulation at physiological pH values was evaluated by studying the AS-48 release at this pH value. The influence of pH and hyperthermia on the AS-48 release from the nano-formulation was also studied. These results show a slower AS-48 release from PLGA[AS-48-BMNPs] compared to previous nano-formulations, which could make this new nano-formulation suitable for longer extended treatments of intracellular pathogens. PLGA[AS-48-BMNPs] are internalized in THP-1 cells where AS-48 is liberated slowly, which may be useful to treat diseases and prevent infection caused by intracellular pathogens. The treatment will be more efficient combined with hyperthermia or photothermia.

Biological Evaluation of New Thienopyridinium and Thienopyrimidinium Derivatives as Human Choline Kinase Inhibitors.

Due to its role in lipid biosynthesis, choline kinase α1 (CKα1) is an interesting target for the development of new antitumor agents. In this work, we present a series of 41 compounds designed based on the well-known and successful strategy of introducing thienopyridine and pyrimidine as bioisosteres of other heterocycles in active antitumor compounds. Notwithstanding the fact that some of these compounds do not show significant enzymatic inhibition, others, in contrast, feature substantially improved enzymatic and antiproliferative inhibition values. This is also confirmed by docking analysis, whereby compounds with longer linkers and thienopyrimidine cationic head have been identified as the most compelling. Among the best compounds is Ff-35, which inhibits the growth of different tumor cells at submicromolar concentrations. Moreover, Ff-35 is more potent in inhibiting CKα1 than other previous biscationic derivatives. Treatment of A549, Hela, and MDA-MB-231 cells with Ff-35 results in their arrest at the G1 phase of the cell cycle. Furthermore, the compound induces cellular apoptosis in a concentration-dependent manner. Altogether, these findings indicate that Ff-35 is a promising new chemotherapeutic agent with encouraging preclinical potential.

New Compounds with Bioisosteric Replacement of Classic Choline Kinase Inhibitors Show Potent Antiplasmodial Activity.

In the fight against Malaria, new strategies need to be developed to avoid resistance of the parasite to pharmaceutics and other prevention barriers. Recently, a Host Directed Therapy approach based on the suppression of the starting materials uptake from the host by the parasite has provided excellent results. In this article, we propose the synthesis of bioisosteric compounds that are capable of inhibiting Plasmodium falciparum Choline Kinase and therefore to reduce choline uptake, which is essential for the development of the parasite. Of the 41 bioisosteric compounds reported herein, none showed any influence of the linker on the antimalarial and enzyme inhibitory activity, whereas an effect of the type of cationic heads used could be observed. SARs determined that the thienopyrimidine substituted in 4 by a pyrrolidine is the best scaffold, independently of the chosen linker. The decrease in lipophilicity seems to improve the antimalarial activity but to cause an opposite effect on the inhibition of the enzyme. While potent compounds with similar good inhibitory values have been related to the proposed mechanism of action, some of them still show discrepancies and further studies are needed to determine their specific molecular target.

Anticancer and Structure Activity Relationship of Non-Symmetrical Choline Kinase Inhibitors.

Choline kinase inhibitors are an outstanding class of cytotoxic compounds useful for the treatment of different forms of cancer since aberrant choline metabolism is a feature of neoplastic cells. Here, we present the most in-depth structure-activity relationship studies of an interesting series of non-symmetric choline kinase inhibitors previously reported by our group: 3a-h and 4a-h. They are characterized by cationic heads of 3-aminophenol bound to 4-(dimethylamino)- or 4-(pyrrolidin-1-yl)pyridinium through several linkers. These derivatives were evaluated both for their inhibitory activity on the enzyme and their antiproliferative activity in a panel of six human tumor cell lines. The compounds with the N-atom connected to the linker (4a-h) show the best inhibitory results, in the manner of results supported by docking studies. On the contrary, the best antiproliferative compounds were those with the O-atom bounded to the linker (3a-h). On the other hand, as was predictable in both families, the inhibitory effect on the enzyme is better the shorter the length of the linker. However, in tumor cells, lipophilicity and choline uptake inhibition could play a decisive role. Interestingly, compounds 3c and 4f, selected for both their ability to inhibit the enzyme and good antiproliferative activity, are endowed with low toxicity in non-tumoral cells (e.g., human peripheral lymphocytes) concerning cancer cells. These compounds were also able to induce apoptosis in Jurkat leukemic cells without causing significant variations of the cell cycle. It is worth mentioning that these derivatives, besides their inhibitory effect on choline kinase, displayed a modest ability to inhibit choline uptake thus suggesting that this mechanism may also contribute to the observed cytotoxicity.

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.

Lead optimization-hit expansion of new asymmetrical pyridinium/quinolinium compounds as choline kinase α1 inhibitors.

AIM: Choline kinase α inhibitors represent one of the newest classes of cytotoxic drugs for cancer treatment, since aberrant choline metabolism is a characteristic shared by many human cancers. RESULTS: Here, we present a new class of asymmetrical pyridinium/quinolinium derivatives developed and designed based on drug optimization. CONCLUSION: Among all compounds described here, compound 8, bearing a 7-chloro-4N-methyl-p-chloroaniline quinolinium moiety, exhibited the greatest inhibitory activity at the enzyme (IC50 = 0.29 µM) and antiproliferative activity in cellular assays (GI50 = 0.29-0.92 µM). Specifically, compound 8 strongly induces a cell-cycle arrest in G1 phase, but it does not significantly induce apoptosis while causing senescence in the MDA-MB-231 cell line.

1,2-Diphenoxiethane salts as potent antiplasmodial agents.

In this article we present a series of non-cytotoxic potent human choline kinase (CK) inhibitors that exhibit nanomolar antiplasmodial activity in vitro. The most active antiplasmodial compounds, 10a-b, bearing a pyridinium cationic head were inactive against CK, while compounds 10g and 10j with a quinolinium moiety exhibit moderate inhibition of both the parasite and the enzyme. The results point towards an additional mechanism of action unrelated to CK inhibition that remains to be established.

New more polar symmetrical bipyridinic compounds: new strategy for the inhibition of choline kinase α1.

AIM: Research of the antitumor properties of biscationic compounds has received significant attention over the last few years. RESULTS: A novel family of 1,1'-([2,2'-bipyridine]-5,5'-diylbis(methylene))bis-substituted bromide (9a-k), containing two nitrogen atoms in the linker, considered as hypothetical hydrogen bond acceptors, were synthesized and evaluated as ChoK inhibitors and their antiproliferative activity against six cancer cell lines. CONCLUSION: The most promising compounds in this series are 1,1'-([2,2'-bipyridine]-5,5'-diylbis(methylene))bis(4-(methyl(phenyl)amino)-quinolinium bromide derivatives 9g-i (analogs to RSM932A), that significantly inhibit cancer cell growth at even submicromolar concentrations, especially against leukemia cells. Compounds 9g-i also inhibit the ChoKα1 with good or moderate values, as predicted by initial docking studies. In addition, the most active compound 9h remarkably induces apoptosis in two cell lines following the mitochondrial pathway.

New non-symmetrical choline kinase inhibitors.

Identification of novel and selective anticancer agents remains an important and challenging goal in pharmacological research. Choline kinase (ChoK) is the first enzyme in the CDP-choline pathway that synthesizes phosphatidylcholine (PC), the major phospholipid in eukaryotic cell membranes. In the present paper, a new family of non-symmetrical monocationic compounds is developed including a 3-aminophenol moiety, bound to 4-(dimethylamino)- or 4-(pyrrolidin-1-yl)pyridinium cationic heads through several linkers. The most promising compounds in these series as ChoK inhibitors are 3f and 4f, while compounds 3c, 3d and 4c are the better antiproliferative agents. The analysis of the biological data observed in the described series of compounds mays represents a platform for the design of more active molecules.

Design, synthesis, theoretical calculations and biological evaluation of new non-symmetrical choline kinase inhibitors.

Inhibition of Choline Kinase (ChoK) has been reported as a therapeutical target in the treatment of some kinds of tumor. In this paper, the design and synthesis of new non-symmetrical monocationic ChoK inhibitors is described, bearing a cationic head and an adenine moiety connected by linkers of different lengths. Docking studies indicate that the cationic head of these compounds could be inserted into the choline binding site of the enzyme, while the adenine moiety could be stabilized into the ATP binding site. Docking studies also support the difference of activity of the synthesized compounds, which depends on both the substituent at position 4 of the cationic head and the linker length, being dimethylamine and 1,4-diphenylbutane respectively, the most appropriate ones. Compounds 14 (IC(50) = 10.70 ± 0.40 µM) and 17 (IC(50) = 6.21 ± 0.97 µM) are the most potent ChoK inhibitors and suitable for further modification with a view to obtain more potent antitumor compounds.