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Insulin resistance (IR), accompanied by an impaired cellular glucose uptake, characterizes diverse pathologies that include, but are not limited to, metabolic disease, prediabetes and type 2 diabetes. Chronic inflammation associated with deranged cellular signaling is thought to contribute to IR. The key molecular players in IR are plasma membrane proteins, including the insulin receptor and glucose transporter 4. Certain natural products, such as lipids, phenols, terpenes, antibiotics and alkaloids have beneficial effects on IR, yet their mode of action remains obscured. We hypothesized that these products belong to a novel class of bioactive molecules that we have named membrane-active immunomodulators (MAIMs). A representative MAIM, the naturally occurring medium chain fatty acid ester diethyl azelate (DEA), has been shown to increase the fluidity of cell plasma membranes with subsequent downstream effects on cellular signaling. DEA has also been shown to improve markers of IR, including blood glucose, insulin and lipid levels, in humans. The literature supports the notion that DEA and other natural MAIMs share similar mechanisms of action in improving IR. These findings shed a new light on the mechanism of IR mitigation using natural products, and may facilitate the discovery of other compounds with similar activities.

Background/aim: Mycobacterium ulcerans causes the necrotizing skin disease Buruli ulcer (BU), characterized by the formation of subcutaneous lesions and immunosuppression thought to be mediated by the virulence factor mycolactone. Since early BU lesions are typically painless, patients often seek standard oral antibiotic therapy at the advanced stages when the treatment is less effective. Given that currently there is no curative topical treatment for BU, our objective was to evaluate a plasma membrane fluidizer, diethyl azelate (DEA), as a potential novel topical therapy for BU., Materials and Methods: We evaluated the effects of DEA against bacterial extracts and live strains of M. ulcerans ATCC 35840 (mycolactone positive; M+) and ATCC 19423 (mycolactone negative; M-) by measuring cytokine levels in cultured cells and tissue extracts using multiplexed immunoassays and numbers of skin lesions as the endpoints., Results: In vitro, DEA counteracted immunosuppression induced by extract from the M+ strain in the 3-D human skin model (EpiDerm) and in human dendritic cells. In vivo, topical DEA reduced immunosuppressive activities of M+ and M- strains at all stages of BU, including advanced ulcers. DEA also diminished lesion formation and ulceration, accelerated healing of skin lesions and preserved normal immune responsiveness to pathogen-associated molecular pattern receptor agonists in blood of infected animals., Conclusion: The efficacy of DEA in BU models is linked to overcoming the immunosuppressive activity of virulence factors produced by M. ulcerans. Thanks to its pluripotent activity, DEA is a promising novel treatment for BU and possibly other pathogenic mycobacteria., (Copyright © 2022, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Brown recluse spider bite releases hemolytic and cytotoxic phospholipase D to the wound that may cause necrosis or even death. We examined diethyl azelate (DEA), a plasma membrane fluidizer with a broad range of immunomodulatory activities, as a potential treatment for the brown recluse spider bite., Materials and Methods: Topical DEA was used in emergency to treat brown recluse spider bites in a human subject. We subsequently evaluated the effects of DEA on hemolysis induced by the brown recluse spider venom, recluse recombinant phospholipase D (rPLD), and venoms from honey bee and moccasin snake, and on phospholipase A2 activity in the bee and snake venoms and in human urine., Results: Topical DEA resolved the consequences of human brown recluse spider envenomation in two weeks. In vitro, DEA inhibited hemolysis caused by the brown recluse spider venom and rPLD and suppressed phospholipase A2 activity in a dose-dependent manner., Conclusion: DEA is a promising novel therapy for the brown recluse spider bite and perhaps even unrelated envenomations involving PLDs., (Copyright © 2022 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Alterations of plasma membrane fluidity are characteristic of many diseases but the intentional modulation of membrane fluidity with drugs has been less studied. We examined the therapeutic potential of the membrane fluidizer diethyl azelate (DEA) and related azelates., Materials and Methods: The effects of azelates on plasma membrane fluidity and cell signaling were examined in primary human and murine cells and in vivo. Endpoints were queried using single target and multiplexed immunoassays., Results: Unique membrane-fluidizing properties and biomarker signatures suggest that azelates are not prodrugs. DEA decreased cytokine signaling from pattern recognition receptors in human dendritic cells, disabled membrane attack of cholera toxin in vitro, and prevented immunosuppression by anthrax lethal toxin in vitro and in vivo. In the murine sepsis model, DEA increased survival and reduced organ damage., Conclusion: Azelates represent a new class of drugs, membrane active immunomodulators, which target an innate homeostatic mechanism, adaptive membrane fluidity modulation., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

The structure of the plasma membrane affects its function. Changes in membrane fluidity with concomitant effects on membrane protein activities and cellular communication often accompany the transition from a healthy to a diseased state. Although deliberate modulation of membrane fluidity with drugs has not been exploited to date, the latest data suggest the "druggability" of the membrane. Azelaic acid esters (azelates) modulate plasma membrane fluidity and exhibit a broad range of immunomodulatory effects in vitro and in vivo. Azelates represent a new class of drugs, membrane active immunomodulators (MAIMs), which use the entire plasma membrane as the target, altering the dynamics of an innate feedback regulated homeostatic system, adaptive membrane fluidity modulation (AMFM). A review of the literature data spanning >200 years supports the notion that molecules in the MAIMs category including known drugs do exert immunomodulatory effects that have been either neglected or dismissed as off-target effects., (Copyright © 2021 International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

Background/aim: Insulin resistance (IR) is linked to increased risk of cardiovascular disease and cancer. We examined safety and efficacy of the natural product diethyl azelate (DEA) in overweight males with a varying degree of IR., Patients and Methods: Seventeen subjects [age 18-42, hemoglobin A1c (A1c) of 5.2-6.2%] received orally 1 mg/kg DEA daily for 21 days. Blood plasma glucose, insulin and lipid levels were assessed before and after treatment., Results: DEA was well tolerated without hypoglycemia or adverse effects except transient diarrhea (n=1). DEA significantly reduced fasting glucose by 6.06 mg/dl (n=8) and insulin by 37.8% (n=8) in subjects with IR and/or A1c ≥5.6%. Furthermore, it improved cholesterol/HDL, LDL/HDL, and non-cholesterol HDL/HDL by 5.4, 6.5, and 6.6%, respectively in all subjects, and by 8.0, 9.8, and 9.8%, respectively in 9 subjects with A1c ≥5.6%., Conclusion: DEA efficacy correlates with the degree of IR. DEA holds promise as a novel treatment for the management of IR., (Copyright© 2020, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

PNT100 is a 24-base, chemically unmodified DNA oligonucleotide sequence that is complementary to a region upstream of the BCL-2 gene. Exposure of tumor cells to PNT100 results in suppression of proliferation and cell death by a process called DNA interference. PNT2258 is PNT100 that is encapsulated in protective amphoteric liposomes developed to efficiently encapsulate the PNT100 oligonucleotide, provide enhanced serum stability, optimized pharmacokinetic properties and antitumor activity of the nanoparticle both in vivo and in vitro. PNT2258 demonstrates broad antitumor activity against BCL-2-driven WSU-DLCL2 lymphoma, highly resistant A375 melanoma, PC-3 prostate, and Daudi-Burkitt's lymphoma xenografts. The sequence specificity of PNT100 was demonstrated against three control sequences (scrambled, mismatched, and reverse complement) all encapsulated in a lipid formulation with identical particle characteristics, and control sequences did not demonstrate antiproliferative activity in vivo or in vitro. PNT2258 is currently undergoing clinical testing to evaluate safety and antitumor activity in patients with recurrent or refractory non-Hodgkin's lymphoma and additional studies are planned.

Background: Lung cancer (LC) is the leading cause of deaths caused by cancer worldwide. A diagnostic test for LC is needed for monitoring high-risk populations., Patients and Methods: Fifty-seven markers were measured using multiplex immunoassays of plasma of patients with non-small cell lung cancer (NSCLC); (245 men, 114 women, 1 unknown), asthma (67 men, 111 women, 2 unknown) and of healthy controls (165 men, 122 women, 1 unknown). Mass spectrometry was used for biomarker discovery. A support vector machine (SVM) was used for data analysis., Results: When all biomarkers and both genders were co-analyzed, SVM classified NSCLC and asthma with an accuracy of 0.94. Restricting to NSCLC versus healthy using best subsets of variables (males: epidermal growth factor (EGF), interleukin-8 (IL-8), soluble Fas (sFas), matrix metalloproteinase-9 (MMP-9), plasminogen activator inhibitor-1 (PAI-1); females: EGF, soluble cluster of differentiation 40 (sCD40) ligand, IL-8) yielded sensitivity and specificity of 1. Expression of eleven mass spectrometric biomarkers differed between pathologies., Conclusion: Significant inter-pathology and gender differences between biomarkers may improve diagnosis of LC.

Aim: To examine changes in biomarkers expressed in breast tumors in response to patient treatment with the polyamine synthesis inhibitor alpha-difluoromethylornithine (DFMO)., Patients and Methods: The expression of Ki-67 (MIB-1), matrix metalloproteinases (MMP) 2 and 9, urokinase-type plasminogen activator (uPA) were examined by immunohistochemistry in breast tissue specimens (controls: n=15, 13 evaluable, and DFMO group; n=27, 21 evaluable). Apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)., Results: Significant increases in apoptosis, MMP-9 and uPA (tumor) were observed in 7 patients >or=50 years who received DFMO for >or=14 days relative to patients <50 years and/or who received <14 days of treatment (n=11). No other measured characteristics, including tumor estrogen and progesterone receptor status, hormone replacement therapy history, histopathological characteristics or tumor grade were correlated with these biomarker changes., Conclusion: Unexpected correlation of proapoptotic DFMO activity in postmenopausal women with breast cancer warrants further study.

Background: A maximum entropy approach is proposed to predict the cytotoxic effects of a panel of colchicine derivatives in several human cancer cell lines. Data was obtained from cytotoxicity assays performed with 21 drug molecules from the same family of colchicine compounds and correlate these results with independent tubulin isoform expression measurements for several cancer cell lines. The maximum entropy method is then used in conjunction with computed relative binding energy values for each of the drug molecules against tubulin isotypes to which these compounds bind with different affinities., Results: We have found by using our analysis that alphabetaI and alphabetaIII tubulin isoforms are the most important isoforms in establishing predictive response of cancer cell sensitivity to colchicine derivatives. However, since alphabetaI tubulin is widely distributed in the human body, targeting it would lead to severe adverse side effects. Consequently, we have identified tubulin isotype alphabetaIII as the most important molecular target for inhibition of microtubule polymerization and hence cancer cell cytotoxicity. Tubulin isotypes alphabetaI and alphabetaII are concluded to be secondary targets., Conclusions: The benefit of being able to correlate expression levels of specific tubulin isotypes and the resultant cell death effect is that it will enable us to better understand the origin of drug resistance and hence design optimal structures for the elimination of cancer cells. The conclusion of the study described herein identifies tubulin isotype alphabetaIII as a target for optimized chemotherapy drug design.