Synthesis and Biological Evaluations of Granulatamide B and its Structural Analogues.

BACKGROUND: While granulatamides A and B have been previously isolated, their biological activities have been only partially examined. The aim of this study was to synthesize granulatamide B (4b), a tryptamine-derivative naturally occurring in Eunicella coral species, using the well-known procedure of Sun and Fürstner and its 12 structural analogues by modifying the side chain, which differs in length, degree of saturation as well as number and conjugation of double bonds. METHOD: The prepared library of compounds underwent comprehensive assessment for their biological activities, encompassing antioxidative, antiproliferative, and antibacterial properties, in addition to in vivo toxicity evaluation using a Zebrafish model. Compound 4i, which consists of a retinoic acid moiety, exhibited the strongest scavenging activity against ABTS radicals (IC50 = 36 ± 2 µM). In addition, 4b and some of the analogues (4a, 4c and 4i), mostly containing an unsaturated chain and conjugated double bonds, showed moderate but non-selective activity with certain IC50 values in the range of 20-40 µM. RESULT: In contrast, the analogue 4l, a derivative of alpha-linolenic acid, was the least toxic towards normal cell lines. Moreover, 4b was also highly active against Gram-positive Bacillus subtilis with an MIC of 125 µM. Nevertheless, both 4b and 4i, known for the best-observed effects, caused remarkable developmental abnormalities in the zebrafish model Danio rerio. CONCLUSION: Since modification of the side chain did not significantly alter the change in biological activities compared to the parent compound, granulatamide B (4b), the substitution of the indole ring needs to be considered. Our group is currently carrying out new syntheses focusing on the functionalization of the indole core.

The Impact of Long-Term Clinoptilolite Administration on the Concentration Profile of Metals in Rodent Organisms.

Heavy metals are dangerous systemic toxicants that can induce multiple organ damage, primarily by inducing oxidative stress and mitochondrial damage. Clinoptilolite is a highly porous natural mineral with a magnificent capacity to eliminate metals from living organisms, mainly by ion-exchange and adsorption, thus providing detoxifying, antioxidant and anti-inflammatory medicinal effects. The in vivo efficiency and safety of the oral administration of clinoptilolite in its activated forms, tribomechanically activated zeolite (TMAZ) and Panaceo-Micro-Activated (PMA) zeolite, as well as the impact on the metallic biodistribution, was examined in healthy female rats. Concentration profiles of Al, As, Cd, Co, Pb, Ni and Sr were measured in rat blood, serum, femur, liver, kidney, small and large intestine, and brain using inductively coupled plasma mass spectrometry (ICP-MS) after a 12-week administration period. Our results point to a beneficial effect of clinoptilolite materials on the concentration profile of metals in female rats supplemented with the corresponding natural clinoptilolite materials, TMAZ and PMA zeolite. The observed decrease of measured toxicants in the kidney, femur, and small and large intestine after three months of oral intake occurred concomitantly with their most likely transient release into the bloodstream (serum) indicative of a detoxification process.

Mediterranean Food Industry By-Products as a Novel Source of Phytochemicals with a Promising Role in Cancer Prevention.

The Mediterranean diet is recognized as a sustainable dietary approach with beneficial health effects. This is highly relevant, although the production of typical Mediterranean food, i.e., olive oil or wine, processed tomatoes and pomegranate products, generates significant amounts of waste. Ideally, this waste should be disposed in an appropriate, eco-friendly way. A number of scientific papers were published recently showing that these by-products can be exploited as a valuable source of biologically active components with health benefits, including anticancer effects. In this review, accordingly, we elaborate on such phytochemicals recovered from the food waste generated during the processing of vegetables and fruits, typical of the Mediterranean diet, with a focus on substances with anticancer activity. The molecular mechanisms of these phytochemicals, which might be included in supporting treatment and prevention of various types of cancer, are presented. The use of bioactive components from food waste may improve the economic feasibility and sustainability of the food processing industry in the Mediterranean region and can provide a new strategy to approach prevention of cancer.

Green solvent-free synthesis of new N-heterocycle-L-ascorbic acid hybrids and their antiproliferative evaluation.

Aim: The authors' aim was to improve the application of copper-catalyzed azide-alkyne cycloaddition in the synthesis of hybrids containing biologically significant nucleobases and L-ascorbic acid scaffolds by introducing an environmentally friendly and waste-free ball mill. Results: Two series of hybrids with a purine, pyrrolo[2,3-d]pyrimidine or 5-substituted pyrimidine attached to 2,3-dibenzyl-L-ascorbic acid via a hydroxyethyl- (15a-23a) or ethylidene-1,2,3-triazolyl (15b-23b) bridge were prepared by ball milling and conventional synthesis. The unsaturated 6-chloroadenine L-ascorbic acid derivative 16b can be highlighted as a lead compound and showed strong antiproliferative activity against HepG2 (hepatocellular carcinoma) and SW620 (colorectal adenocarcinoma) cells. Conclusion: Mechanochemical synthesis was superior in terms of sustainability, reaction rate and yield, highlighting the advantageous applications of ball milling over classical reactions.

Anticancer Activities of Marine-Derived Phenolic Compounds and Their Derivatives.

Since the middle of the last century, marine organisms have been identified as producers of chemically and biologically diverse secondary metabolites which have exerted various biological activities including anticancer, anti-inflammatory, antioxidant, antimicrobial, antifouling and others. This review primarily focuses on the marine phenolic compounds and their derivatives with potent anticancer activity, isolated and/or modified in the last decade. Reports on the elucidation of their structures as well as biosynthetic studies and total synthesis are also covered. Presented phenolic compounds inhibited cancer cells proliferation or migration, at sub-micromolar or nanomolar concentrations (lamellarins D (37), M (38), K (39), aspergiolide B (41), fradimycin B (62), makulavamine J (66), mayamycin (69), N-acetyl-N-demethylmayamycin (70) or norhierridin B (75)). In addition, they exhibited anticancer properties by a diverse biological mechanism including induction of apoptosis or inhibition of cell migration and invasive potential. Finally, phlorotannins 1-7 and bromophenols 12-29 represent the most researched phenolic compounds, of which the former are recognized as protective agents against UVB or gamma radiation-induced skin damages. Finally, phenolic metabolites were assorted into six main classes: phlorotannins, bromophenols, flavonoids, coumarins, terpenophenolics, quinones and hydroquinones. The derivatives that could not be attributed to any of the above-mentioned classes were grouped in a separate class named miscellaneous compounds.

Chemical Evaluation, Antioxidant, Antiproliferative, Anti-Inflammatory and Antibacterial Activities of Organic Extract and Semi-Purified Fractions of the Adriatic Sea Fan, Eunicella cavolini.

Due to sedentary lifestyle and harsh environmental conditions, gorgonian coral extracts are recognized as a rich source of novel compounds with various biological activities, of interest to the pharmaceutical and cosmetic industries. The presented study aimed to perform chemical screening of organic extracts and semi-purified fractions obtained from the common Adriatic gorgonian, sea fan, Eunicella cavolini (Koch, 1887) and explore its abilities to exert different biological effects in vitro. Qualitative chemical evaluation revealed the presence of several classes of secondary metabolites extended with mass spectrometry analysis and tentative dereplication by using Global Natural Product Social Molecular Networking online platform (GNPS). Furthermore, fractions F4 and F3 showed the highest phenolic (3.28 ± 0.04 mg GAE/g sample) and carotene (23.11 ± 2.48 mg ß-CA/g sample) content, respectively. The fraction F3 inhibited 50% of DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and ABTS (2,2'-azino-bis (3-ethylbenzthiazolin-6-yl) sulfonic acid) radicals at the concentrations of 767.09 ± 11.57 and 157.16 ± 10.83 µg/mL, respectively. The highest anti-inflammatory potential was exhibited by F2 (IC50 = 198.70 ± 28.77 µg/mL) regarding the inhibition of albumin denaturation and F1 (IC50 = 254.49 ± 49.17 µg/mL) in terms of soybean lipoxygenase inhibition. In addition, the most pronounced antiproliferative effects were observed for all samples (IC50 ranging from 0.82 ± 0.14-231.18 ± 46.13 µg/mL) against several carcinoma cell lines, but also towards non-transformed human fibroblasts pointing to a generally cytotoxic effect. In addition, the antibacterial activity was tested by broth microdilution assay against three human pathogenic bacteria: Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. The latter was the most affected by fractions F2 and F3. Finally, further purification, isolation and characterization of pure compounds from the most active fractions are under investigation.

Preparation of Multifunctional N-Doped Carbon Quantum Dots from Citrus clementina Peel: Investigating Targeted Pharmacological Activities and the Potential Application for Fe3+ Sensing.

Carbon quantum dots (CQDs) have recently emerged as innovative theranostic nanomaterials, enabling fast and effective diagnosis and treatment. In this study, a facile hydrothermal approach for N-doped biomass-derived CQDs preparation from Citrus clementina peel and amino acids glycine (Gly) and arginine (Arg) has been presented. The gradual increase in the N-dopant (amino acids) nitrogen content increased the quantum yield of synthesized CQDs. The prepared CQDs exhibited good biocompatibility, stability in aqueous, and high ionic strength media, similar optical properties, while differences were observed regarding the structural and chemical diversity, and biological and antioxidant activity. The antiproliferative effect of CQD@Gly against pancreatic cancer cell lines (CFPAC-1) was observed. At the same time, CQD@Arg has demonstrated the highest quantum yield and antioxidant activity by DPPH scavenging radical method of 81.39 ± 0.39% and has been further used for the ion sensing and cellular imaging of cancer cells. The obtained results have demonstrated selective response toward Fe3+ detection, with linear response ranging from 7.0 µmol dm-3 to 50.0 µmol dm-3 with R2 = 0.9931 and limit of detection (LOD) of 4.57 ± 0.27 µmol dm-3. This research could be a good example of sustainable biomass waste utilization with potential for biomedical analysis and ion sensing applications.

Bioactives from Bee Products and Accompanying Extracellular Vesicles as Novel Bioactive Components for Wound Healing.

In recent years, interest has surged among researchers to determine compounds from bee products such as honey, royal jelly, propolis and bee pollen, which are beneficial to human health. Mass spectrometry techniques have shown that bee products contain a number of proven health-promoting compounds but also revealed rather high diversity in the chemical composition of bee products depending on several factors, such as for example botanical sources and geographical origin. In the present paper, we present recent scientific advances in the field of major bioactive compounds from bee products and corresponding regenerative properties. We also discuss extracellular vesicles from bee products as a potential novel bioactive nutraceutical component. Extracellular vesicles are cell-derived membranous structures that show promising potential in various therapeutic areas. It has been extensively reported that the use of vesicles, which are naturally formed in plant and animal cells, as delivery agents have many advantages. Whether the use of extracellular vesicles from bee products represents a new solution for wound healing remains still to be elucidated. However, promising results in specific applications of the bee products in wound healing and tissue regenerative properties of extracellular vesicles provide a good rationale to further explore this idea.

Novel Bis- and Mono-Pyrrolo[2,3-d]pyrimidine and Purine Derivatives: Synthesis, Computational Analysis and Antiproliferative Evaluation.

Novel symmetrical bis-pyrrolo[2,3-d]pyrimidines and bis-purines and their monomers were synthesized and evaluated for their antiproliferative activity in human lung adenocarcinoma (A549), cervical carcinoma (HeLa), ductal pancreatic adenocarcinoma (CFPAC-1) and metastatic colorectal adenocarcinoma (SW620) cells. The use of ultrasound irradiation as alternative energy input in Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) shortened the reaction time, increased the reaction efficiency and led to the formation of exclusively symmetric bis-heterocycles. DFT calculations showed that triazole formation is exceedingly exergonic and confirmed that the presence of Cu(I) ions is required to overcome high kinetic requirements and allow the reaction to proceed. The influence of various linkers and 6-substituted purine and regioisomeric 7-deazapurine on their cytostatic activity was revealed. Among all the evaluated compounds, the 4-chloropyrrolo[2,3-d]pyrimidine monomer 5f with 4,4'-bis(oxymethylene)biphenyl had the most pronounced, although not selective, growth-inhibitory effect on pancreatic adenocarcinoma (CFPAC-1) cells (IC50 = 0.79 µM). Annexin V assay results revealed that its strong growth inhibitory activity against CFPAC-1 cells could be associated with induction of apoptosis and primary necrosis. Further structural optimization of bis-chloropyrrolo[2,3-d]pyrimidine with aromatic linker is required to develop novel efficient and non-toxic agent against pancreatic cancer.

Amidino substituted 2-aminophenols: biologically important building blocks for the amidino-functionalization of 2-substituted benzoxazoles.

Unlike the closely related and widely investigated amidino-substituted benzimidazoles and benzothiazoles with a range of demonstrated biological activities, the matching benzoxazole analogues still remain a largely understudied and not systematically evaluated class of compounds. To address this challenge, we utilized the Pinner reaction to convert isomeric cyano-substituted 2-aminophenols into their amidine derivatives, which were isolated as hydrochlorides and/or zwitterions, and whose structure was confirmed by single crystal X-ray diffraction. The key step during the Pinner synthesis of the crucial carboximidate intermediates was characterized through mechanistic DFT calculations, with the obtained kinetic and thermodynamic parameters indicating full agreement with the experimental observations. The obtained amidines were subjected to a condensation reaction with aryl carboxylic acids that allowed the synthesis of a new library of 5- and 6-amidino substituted 2-arylbenzoxazoles. Their antiproliferative features against four human tumour cell lines (SW620, HepG2, CFPAC-1, HeLa) revealed sub-micromolar activities on SW620 for several cyclic amidino 2-naphthyl benzoxazoles, thus demonstrating the usefulness of the proposed synthetic strategy and promoting amidino substituted 2-aminophenols as important building blocks towards biologically active systems.

Mass spectrometry-based glycomic profiling of the total IgG and total proteome N-glycomes isolated from follicular fluid.

Couples with infertility issues have been assisted by in vitro fertilization reproduction technologies with high success rates of 50-80%. However, complications associated with ovarian stimulation remain, such as ovarian hyperstimulation. Oocyte quality is a significant factor impacting the outcome of in vitro fertilization procedures, but other processes are also critical for fertilization success. Increasing evidence points to aberrant inflammation as one of these critical processes reflected in molecular changes, including glycosylation of proteins. Here we report results from a MALDI-TOF-MS-based glycomic profiling of the total IgG and total proteome N-glycomes isolated from the follicular fluid obtained from patients undergoing fertilization through either (1) assisted reproduction by modified natural cycle or (2) controlled ovarian stimulation (GnRH antagonist, GnRH Ant) protocols. Significant inflammatory-related differences between analyzed N-glycomes were observed from samples and correlated with the ovarian stimulation protocol used in patients.

Technological Advances in Preclinical Drug Evaluation: The Role of -Omics Methods.

Preclinical drug development is an essential step in the drug development process where the evaluation of new chemical entities occurs. In particular, preclinical drug development phases include deep analysis of drug candidates' interactions with biomolecules/targets, their safety, toxicity, pharmacokinetics, metabolism by use of assays in vitro and in vivo animal assays. Legal aspects of the required procedures are well-established. Herein, we present a comprehensive summary of current state-of-the art approaches and techniques used in preclinical studies. In particular, we will review the potential of new, -omics methods and platforms for mechanistic evaluation of drug candidates and speed-up of the preclinical evaluation steps.

Targeting Tumour Metastasis: The Emerging Role of Nanotechnology.

The metastatic process has still not been completely elucidated, probably due to insufficient knowledge of the underlying mechanisms. Here, we provide an overview of the current findings that shed light on specific molecular alterations associated with metastasis and present novel concepts in the treatment of the metastatic process. In particular, we discuss novel pharmacological approaches in the clinical setting that target metastatic progression. New insights into the process of metastasis allow optimisation and design of new treatment strategies, especially in view of the fact that metastatic cells share common features with stem cells. Nano- and micro-technologies are herein elaborated in details as a promising therapeutic concept in targeted drug delivery for metastatic cancer. Progression in the field could provide a more efficient way to tackle metastasis and thus bring about advancements in the treatment and management of patients with advanced cancer.

Antiproliferative activity and mode of action analysis of novel amino and amido substituted phenantrene and naphtho[2,1-b]thiophene derivatives.

Herein we present and describe the design and synthesis of novel phenantrene derivatives substituted with either amino or amido side chains and their biological activity. Antiproliferative activities were assessed in vitro on a panel of human cancer cell lines. Tested compounds showed moderate activity against cancer cells in comparison with 5-fluorouracile. Among all tested compounds, some compounds substituted with cyano groups showed a pronounced and selective activity in the nanomolar range of inhibitory concentrations against HeLa and HepG2. The strongest selective activity against HeLa cells was observed for acrylonitriles 8 and 11 and their cyclic analogues 15 and 17 substituted with two cyano groups with a corresponding IC50 = 0.33, 0.21, 0.65 and 0.45 µM, respectively. Compounds 11 showed the most pronounced selectivity being almost non cytotoxic to normal fibroblasts. Additionally, mode of biological action analysis was performed in silico and in vitro by Western blot analysis of HIF-1-α relative expression for compounds 8 and 11.

Antitumor and antiviral activities of 4-substituted 1,2,3-triazolyl-2,3-dibenzyl-L-ascorbic acid derivatives.

Two series of 6-(1,2,3-triazolyl)-2,3-dibenzyl-l-ascorbic acid derivatives with the hydroxyethylene (8a-8u) and ethylidene linkers (10c-10p) were synthesized and evaluated for their antiproliferative activity against seven malignant tumor cell lines and antiviral activity against a broad range of viruses. Conformationally unrestricted spacer between the lactone and 1,2,3-triazole units in 8a-8u series had a profound effect on antitumor activity. Besides, the introduction of a long side chain at C-4 of 1,2,3-triazole that led to the synthesis of decyl-substituted 2,3-dibenzyl-l-ascorbic acid 8m accounted for a selective and potent antiproliferative activity on breast cancer MCF-7 cells cells in the nM range. Further analysis showed that compound 8m strongly enhanced expression of hypoxia inducible transcription factor 1 α (HIF-1α) and to some extent decreased expression of nitric oxide synthase 2 (NOS2) suggesting its role in regulating HIF-1α signalling pathway. The p-methoxyphenyl-substituted derivative 10g displayed specific anti-cytomegalovirus (CMV) potential, whereas aliphatic-substituted derivatives 8l and 8m had the most potent, yet relatively non-specific, anti-varicella-zoster (VZV) activity.

The Antioxidant and Antiproliferative Activities of 1,2,3-Triazolyl-L-Ascorbic Acid Derivatives.

The novel 4-substituted 1,2,3-triazole L-ascorbic acid (L-ASA) conjugates with hydroxyethylene spacer as well as their conformationally restricted 4,5-unsaturated analogues were synthesized as potential antioxidant and antiproliferative agents. An evaluation of the antioxidant activity of novel compounds showed that the majority of the 4,5-unsaturated L-ASA derivatives showed a better antioxidant activity compared to their saturated counterparts. m-Hydroxyphenyl (7j), p-pentylphenyl (7k) and 2-hydroxyethyl (7q) substituted 4,5-unsaturated 1,2,3-triazole L-ASA derivatives exhibited very efficient and rapid (within 5 min) 2,2-diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging activity (7j, 7k: IC50 = 0.06 mM; 7q: IC50 = 0.07 mM). In vitro scavenging activity data were supported by in silico quantum-chemical modelling. Thermodynamic parameters for hydrogen-atom transfer and electron-transfer radical scavenging pathways of anions deprotonated at C2-OH or C3-OH groups of L-ASA fragments were calculated. The structure activity analysis (SAR) through principal component analysis indicated radical scavenging activity by the participation of OH group with favorable reaction parameters: the C3-OH group of saturated C4-C5(OH) derivatives and the C2-OH group of their unsaturated C4=C5 analogues. The antiproliferative evaluation showed that p-bromophenyl (4e: IC50 = 6.72 µM) and p-pentylphenyl-substituted 1,2,3-triazole L-ASA conjugate (4k: IC50 = 26.91 µM) had a selective cytotoxic effect on breast adenocarcinoma MCF-7 cells. Moreover, compound 4e did not inhibit the growth of foreskin fibroblasts (IC50 > 100 µM). In MCF-7 cells treated with 4e, a significant increase of hydroxylated hypoxia-inducible transcription factor 1 alpha (HIF-1α) expression and decreased expression of nitric oxide synthase 2 (NOS2) were observed, suggesting the involvement of 4e in the HIF-1α signaling pathway for its strong growth-inhibition effect on MCF-7 cells.

Polyphenol-Based Design of Functional Olive Leaf Infusions§.

The beneficial properties of polyphenols are widely recognized, and polyphenol-rich olive oil, which is part of the typical Mediterranean diet, has been identified as having positive health effects. However, over the past decade, olive leaves have been discovered as an alternative polyphenol-rich source. This is particularly interesting in the context of the growing interest in functional foods, as well as in terms of the management of biological waste, including olive leaves that are left over from the production of olive oil. Previous studies on olive leaves confirmed that they have a high phenolic content, which explains their previously described strong antibacterial, antimicrobial and antiviral activity. Therefore, the major aim of our work is to comprehensively determine olive leaf phenolic content in cultivars Istarska bjelica, Leccino and Buza as a natural source of bioactive compounds suitable for daily consumption in the form of infusion. For this purpose, we examined the influence of olive leaf cultivar, maceration time and temperature on the phenolic composition of final infusions. Phenolic compounds were analysed by liquid chromatography (LC) coupled to a triple quadrupole mass spectrometer (LC-QQQ). As expected, the results indicate the significant influence of not only the olive cultivar but also of maceration parameters on the qualitative and quantitative phenolic composition. The highest phenolic compound content was obtained in the infusion of Istarska bjelica leaves after 15 min of maceration. However, the Buza olive leaf infusion had the most diverse phenolic composition. Furthermore, we designed several functional olive leaf infusion mixtures with phenolic compositions adjusted based on the desired health effect. The results show the role of phenolic composition adjustment in the development and improvement of the quality of functional olive leaf infusions.

Bioactive Sphingolipids as Biomarkers Predictive of Disease Severity and Treatment Response in Cancer: Current Status and Translational Challenges.

Recent translational studies in cancer have produced a wealth of evidence to support an association between sphingolipid metabolism and clinical outcomes, which underscores the clinical importance of sphingolipid-related biomarkers in cancer diagnosis and prognosis. Importantly, circulating levels of bioactive sphingolipids were demonstrated to correlate with patient survival and treatment response in different tumour types, which could provide novel non-invasive cancer biomarkers. Here, we give a comprehensive overview of recent findings on bioactive sphingolipid species and protein regulators of their metabolism and signalling as novel potential biomarkers for risk assessment, prevention and prediction of treatment response in several types of solid cancers, including prostate, liver, pancreatic, breast and colon cancer, head and neck squamous cell carcinoma and gliomas. Finally, we critically discuss current issues in clinical translation of sphingolipid biomarkers and give our perspective on how these problems could be handled to facilitate implementation of sphingolipid-based diagnostics into clinical practice.

Secondary Metabolites from Gorgonian Corals of the Genus Eunicella: Structural Characterizations, Biological Activities, and Synthetic Approaches.

Gorgonian corals, which belong to the genus Eunicella, are known as natural sources of diverse compounds with unique structural characteristics and interesting bioactivities both in vitro and in vivo. This review is focused primarily on the secondary metabolites isolated from various Eunicella species. The chemical structures of 64 compounds were divided into three main groups and comprehensively presented: a) terpenoids, b) sterols, and c) alkaloids and nucleosides. The observed biological activities of depicted metabolites with an impact on cytotoxic, anti-inflammatory, and antimicrobial activities were reviewed. The most promising biological activities of certain metabolites point to potential candidates for further development in pharmaceutical, cosmetic, and other industries, and are highlighted. Total synthesis or the synthetic approaches towards the desired skeletons or natural products are also summarized.

Acid ceramidase inhibition sensitizes human colon cancer cells to oxaliplatin through downregulation of transglutaminase 2 and ß1 integrin/FAK-mediated signalling.

Acid ceramidase (ASAH1) has been implicated in the progression and chemoresistance in different cancers. Its role in colon cancer biology and response to standard chemotherapy has been poorly addressed so far. Here, we have investigated ASAH1 expression at the protein level in human colon cancer cell lines and tissues from colon cancer patients, and have examined in vitro the possible link between ASAH1 expression and functional activity of p53 protein whose inactivation is associated with the progression from adenoma to malignant tumour in colon cancer. Finally, we have explored the role of ASAH1 in response and resistance mechanisms to oxaliplatin (OXA) in HCT 116 colon cancer cells. We have demonstrated that human colon cancer cells and colorectal adenocarcinoma tissues constitutively express ASAH1, and that its expression is higher in tumour tissues than in normal colonic mucosa. Furthermore, we found an inverse correlation between ASAH1 expression and p53 functional activity. Obtained data revealed that ASAH1 was involved in HCT 116 cell response to OXA and that anti-proliferative, pro-apoptotic, anti-migratory and anti-clonogenic effects of OXA could be significantly increased by combination treatment with ASAH1 inhibitor carmofur. Increased OXA sensitivity was associated with downregulation of signalling involved in acquired resistance to OXA in colon cancer, in particular transglutaminase 2 and ß1 integrin/FAK, which resulted in the suppression of NF-κB and Akt. Thus, combination of OXA with ASAH1 inhibitors could be a promising strategy to counter chemoresistance and improve treatment outcome in advanced colon cancer.