The Interaction of the Endocannabinoid Anandamide and Paracannabinoid Lysophosphatidylinositol during Cell Death Induction in Human Breast Cancer Cells.

Endocannabinoid anandamide (AEA) and paracannabinoid lysophosphatidylinositol (LPI) play a significant role in cancer cell proliferation regulation. While anandamide inhibits the proliferation of cancer cells, LPI is known as a cancer stimulant. Despite the known endocannabinoid receptor crosstalk and simultaneous presence in the cancer microenvironment of both molecules, their combined activity has never been studied. We evaluated the effect of LPI on the AEA activity in six human breast cancer cell lines of different carcinogenicity (MCF-10A, MCF-7, BT-474, BT-20, SK-BR-3, MDA-MB-231) using resazurin and LDH tests after a 72 h incubation. AEA exerted both anti-proliferative and cytotoxic activity with EC50 in the range from 31 to 80 µM. LPI did not significantly affect the cell viability. Depending on the cell line, the response to the LPI-AEA combination varied from a decrease in AEA cytotoxicity to an increase in it. Based on the inhibitor analysis of the endocannabinoid receptor panel, we showed that for the former effect, an active GPR18 receptor was required and for the latter, an active CB2 receptor. The data obtained for the first time are important for the understanding the manner by which endocannabinoid receptor ligands acting simultaneously can modulate cancer growth at different stages.

Multicomponent Lipid Nanoparticles for RNA Transfection.

Despite the wide variety of available cationic lipid platforms for the delivery of nucleic acids into cells, the optimization of their composition has not lost its relevance. The purpose of this work was to develop multi-component cationic lipid nanoparticles (LNPs) with or without a hydrophobic core from natural lipids in order to evaluate the efficiency of LNPs with the widely used cationic lipoid DOTAP (1,2-dioleoyloxy-3-[trimethylammonium]-propane) and the previously unstudied oleoylcholine (Ol-Ch), as well as the ability of LNPs containing GM3 gangliosides to transfect cells with mRNA and siRNA. LNPs containing cationic lipids, phospholipids and cholesterol, and surfactants were prepared according to a three-stage procedure. The average size of the resulting LNPs was 176 nm (PDI 0.18). LNPs with DOTAP mesylate were more effective than those with Ol-Ch. Core LNPs demonstrated low transfection activity compared with bilayer LNPs. The type of phospholipid in LNPs was significant for the transfection of MDA-MB-231 and SW 620 cancer cells but not HEK 293T cells. LNPs with GM3 gangliosides were the most efficient for the delivery of mRNA to MDA-MB-231 cells and siRNA to SW620 cells. Thus, we developed a new lipid platform for the efficient delivery of RNA of various sizes to mammalian cells.

Co-delivery of paclitaxel and etoposide prodrug by human serum albumin and PLGA nanoparticles: synergistic cytotoxicity in brain tumour cells.

The aims of this study were to develop co-delivery systems of paclitaxel (PTX) and etoposide prodrug (4'-O-benzyloxycarbonyl-etoposide, ETP-cbz) based on non-cross-linked human serum albumin (HSA) and poly(lactide-co-glycolide) nanoparticles and to evaluate the synergistic potential of these drugs in vitro. The nanoformulations were prepared by the high-pressure homogenisation technique and characterised using DLS, TEM, SEM, AFM, HPLC, CZE, in-vitro release, and cytotoxicity in human and murine glioma cells. All nanoparticles had 90-150 nm in size and negative ζ-potentials. The Neuro2A cells were the most sensitive to both HSA- and PLGA-based co-delivery systems (IC50 0.024 µM and 0.053 µM, respectively). The drugs' synergistic effect (combination index < 0.9) was observed in the GL261 cells for both types of co-delivery formulations and in the Neuro2A cells for the HSA-based system. These nanodelivery systems may be useful to improve combination chemotherapy for brain tumour treatment. To our knowledge, this is the first report describing the non-cross-linked HSA-based co-delivery nanosuspension which was prepared using nab™ technology.

The Mechanisms of GPR55 Receptor Functional Selectivity during Apoptosis and Proliferation Regulation in Cancer Cells.

GPR55 is a non-canonical cannabinoid receptor, important for cancer proliferation. Depending on the ligand, it induces either cell proliferation or death. The objective of the study was to establish the mechanisms of this multidirectional signaling. Using the CRISPR-Cas9 system, the GPR55, CB1, CB2, and GPR18 receptor knockouts of the MDA-MB-231 line were obtained. After the CB2 receptor knockout, the pro-apoptotic activity of the pro-apoptotic ligand docosahexaenoyl dopamine (DHA-DA) slightly increased, while the pro-proliferative activity of the most active synthetic ligand of the GPR55 receptor (ML-184) completely disappeared. On the original cell line, the stimulatory effect of ML-184 was removed by the CB2 receptor blocker and by GPR55 receptor knockout. Thus, it can be confidently assumed that when proliferation is stimulated with the participation of the GPR55 receptor, a signal is transmitted from the CB2 receptor to the GPR55 receptor due to the formation of a heterodimer. GPR18 was additionally involved in the implementation of the pro-apoptotic effect of DHA-DA, while the CB1 receptor is not involved. In the implementation of the pro-apoptotic action of DHA-DA, the elimination of Gα13 led to a decrease in cytotoxicity. The obtained data provide novel details to the mechanism of the pro-proliferative action of GPR55.

Anti-Proliferative and Cytoprotective Activity of Aryl Carbamate and Aryl Urea Derivatives with Alkyl Groups and Chlorine as Substituents.

Natural cytokinines are a promising group of cytoprotective and anti-tumor agents. In this research, we synthesized a set of aryl carbamate, pyridyl urea, and aryl urea cytokinine analogs with alkyl and chlorine substitutions and tested their antiproliferative activity in MDA-MB-231, A-375, and U-87 MG cell lines, and cytoprotective properties in H2O2 and CoCl2 models. Aryl carbamates with the oxamate moiety were selectively anti-proliferative for the cancer cell lines tested, while the aryl ureas were inactive. In the cytoprotection studies, the same aryl carbamates were able to counteract the CoCl2 cytotoxicity by 3-8%. The possible molecular targets of the aryl carbamates during the anti-proliferative action were the adenosine A2 receptor and CDK2. The obtained results are promising for the development of novel anti-cancer therapeutics.

N-Acyl Dopamines Induce Apoptosis in Endometrial Stromal Cells from Patients with Endometriosis.

Endometriosis is characterized by the formation and development of endometrial tissues outside the uterus, based on an imbalance between proliferation and cell death, leading to the uncontrolled growth of ectopic foci. The potential target for the regulation of these processes is the endocannabinoid system, which was found to be involved in the migration, proliferation, and survival of tumor cells. In this paper, we investigated the effect of endocannabinoid-like compounds from the N-acyl dopamine (NADA) family on the viability of stromal cells from ectopic and eutopic endometrium of patients with ovarian endometriosis. N-arachidonoyldopamine, N-docosahexaenoyldopamine, and N-oleoyldopamine have been shown to have a five-times-more-selective cytotoxic effect on endometrioid stromal cells. To study the mechanisms of the toxic effect, inhibitory analysis, measurements of caspase-3/9 activity, reactive oxygen species, and the mitochondrial membrane potential were performed. It was found that NADA induced apoptosis via an intrinsic pathway through the CB1 receptor and downstream serine palmitoyltransferase, NO synthase activation, increased ROS production, and mitochondrial dysfunction. The higher selectivity of NADA for endometriotic stromal cells and the current lack of effective drug treatment can be considered positive factors for further research of these compounds as possible therapeutic agents against endometriosis.

ACTH(6-9)PGP Peptide Protects SH-SY5Y Cells from H2O2, tert-Butyl Hydroperoxide, and Cyanide Cytotoxicity via Stimulation of Proliferation and Induction of Prosurvival-Related Genes.

Stabilized melanocortin analog peptide ACTH(6-9)PGP (HFRWPGP) possesses a wide range of neuroprotective activities. However, its mechanism of action remains poorly understood. In this paper, we present a study of the proproliferative and cytoprotective activity of the adrenocorticotropic hormone fragment 6-9 (HFRW) linked with the peptide prolyine-glycyl-proline on the SH-SY5Y cells in the model of oxidative stress-related toxicity. The peptide dose-dependently protected cells from H2O2, tert-butyl hydroperoxide, and KCN and demonstrated proproliferative activity. The mechanism of its action was the modulation of proliferation-related NF-κB genes and stimulation of prosurvival NRF2-gene-related pathway, as well as a decrease in apoptosis.

GPR55 Receptor Activation by the N-Acyl Dopamine Family Lipids Induces Apoptosis in Cancer Cells via the Nitric Oxide Synthase (nNOS) Over-Stimulation.

GPR55 is a GPCR of the non-CB1/CB2 cannabinoid receptor family, which is activated by lysophosphatidylinositol (LPI) and stimulates the proliferation of cancer cells. Anandamide, a bioactive lipid endocannabinoid, acts as a biased agonist of GPR55 and induces cancer cell death, but is unstable and psychoactive. We hypothesized that other endocannabinoids and structurally similar compounds, which are more hydrolytically stable, could also induce cancer cell death via GPR55 activation. We chemically synthesized and tested a set of fatty acid amides and esters for cell death induction via GPR55 activation. The most active compounds appeared to be N-acyl dopamines, especially N-docosahexaenoyl dopamine (DHA-DA). Using a panel of cancer cell lines and a set of receptor and intracellular signal transduction machinery inhibitors together with cell viability, Ca2+, NO, ROS (reactive oxygen species) and gene expression measurement, we showed for the first time that for these compounds, the mechanism of cell death induction differed from that published for anandamide and included neuronal nitric oxide synthase (nNOS) overstimulation with concomitant oxidative stress induction. The combination of DHA-DA with LPI, which normally stimulates cancer proliferation and is increased in cancer setting, had an increased cytotoxicity for the cancer cells indicating a therapeutic potential.

N-arachidonoyl dopamine inhibits epithelial-mesenchymal transition of breast cancer cells through ERK signaling and decreasing the cellular cholesterol.

N-acyl dopamines (NADAs) are bioactive lipids of the endovanilloid family with known cytotoxicity for the cancer cells; however, the available data on the participation of the endovanilloids in epithelial-mesenchymal transition (EMT) and cancer stemness are controversial. This study unveils the inhibitory role of N-arachidonoyl dopamine (AA-DA), a typical representative of the NADA family, in breast cancer cell migration, EMT, and stemness. AA-DA treatment also led to a decrease in cholesterol biosynthesis gene expressions, and addition of exogenous cholesterol reverted these AA-DA-mediated inhibitory effects. Notably, AA-DA treatment inhibited the key regulatory gene of the cholesterol biosynthesis pathway, sterol regulatory element-binding protein 1 (SREBP1), with concurrent repression of the endoplasmic reticulum kinase 1/2 (ERK1/2) pathway. Furthermore, U0126, an ERK inhibitor, inhibited SREBP1 and decreased cellular cholesterol level, unwinding the molecular mechanism behind AA-DA-mediated anticancer activity. Thus, we, for the first time, revealed that AA-DA counteracts breast cancer EMT via inhibition of ERK signaling and cholesterol content.

In Vivo Targeted Metabolomic Profiling of Prostanit, a Novel Anti-PAD NO-Donating Alprostadil-Based Drug.

Prostanit is a novel drug developed for the treatment of peripheral arterial diseases. It consists of a prostaglandin E1 (PGE1) moiety with two nitric oxide (NO) donor fragments, which provide a combined vasodilation effect on smooth muscles and vascular spastic reaction. Prostanit pharmacokinetics, however, remains poorly investigated. Thus, the object of this study was to investigate the pharmacokinetics of Prostanit-related and -affected metabolites in rabbit plasma using the liquid chromatography-mass spectrometry (LC-MS) approach. Besides, NO generation from Prostanit in isolated rat aorta and human smooth muscle cells was studied using the Griess method. In plasma, Prostanit was rapidly metabolized to 1,3-dinitroglycerol (1,3-DNG), PGE1, and 13,14-dihydro-15-keto-PGE1. Simultaneously, the constant growth of amino acid (proline, 4-hydroxyproline, alanine, phenylalanine, etc.), steroid (androsterone and corticosterone), and purine (adenosine, adenosine-5 monophosphate, and guanosine) levels was observed. Glycine, aspartate, cortisol, and testosterone levels were decreased. Ex vivo Prostanit induced both NO synthase-dependent and -independent NO generation. The observed pharmacokinetic properties suggested some novel beneficial activities (i.e., effect prolongation and anti-inflammation). These properties may provide a basis for future research of the effectiveness and safety of Prostanit, as well as for its characterization from a clinical perspective.

Capmatinib in MET Exon 14-Mutated or MET-Amplified Non-Small-Cell Lung Cancer.

BACKGROUND: Among patients with non-small-cell lung cancer (NSCLC), MET exon 14 skipping mutations occur in 3 to 4% and MET amplifications occur in 1 to 6%. Capmatinib, a selective inhibitor of the MET receptor, has shown activity in cancer models with various types of MET activation. METHODS: We conducted a multiple-cohort, phase 2 study evaluating capmatinib in patients with MET-dysregulated advanced NSCLC. Patients were assigned to cohorts on the basis of previous lines of therapy and MET status (MET exon 14 skipping mutation or MET amplification according to gene copy number in tumor tissue). Patients received capmatinib (400-mg tablet) twice daily. The primary end point was overall response (complete or partial response), and the key secondary end point was response duration; both end points were assessed by an independent review committee whose members were unaware of the cohort assignments. RESULTS: A total of 364 patients were assigned to the cohorts. Among patients with NSCLC with a MET exon 14 skipping mutation, overall response was observed in 41% (95% confidence interval [CI], 29 to 53) of 69 patients who had received one or two lines of therapy previously and in 68% (95% CI, 48 to 84) of 28 patients who had not received treatment previously; the median duration of response was 9.7 months (95% CI, 5.6 to 13.0) and 12.6 months (95% CI, 5.6 to could not be estimated), respectively. Limited efficacy was observed in previously treated patients with MET amplification who had a gene copy number of less than 10 (overall response in 7 to 12% of patients). Among patients with MET amplification and a gene copy number of 10 or higher, overall response was observed in 29% (95% CI, 19 to 41) of previously treated patients and in 40% (95% CI, 16 to 68) of those who had not received treatment previously. The most frequently reported adverse events were peripheral edema (in 51%) and nausea (in 45%); these events were mostly of grade 1 or 2. CONCLUSIONS: Capmatinib showed substantial antitumor activity in patients with advanced NSCLC with a MET exon 14 skipping mutation, particularly in those not treated previously. The efficacy in MET-amplified advanced NSCLC was higher in tumors with a high gene copy number than in those with a low gene copy number. Low-grade peripheral edema and nausea were the main toxic effects. (Funded by Novartis Pharmaceuticals; GEOMETRY mono-1 ClinicalTrials.gov number, NCT02414139.).

Novel bexarotene derivatives: Synthesis and cytotoxicity evaluation for glioma cells in 2D and 3D in vitro models.

Glioblastoma (GBM) is an aggressive and lethal form of brain cancer with a high invasion capacity and a lack of effective chemotherapeutics. Retinoid bexarotene (BXR) inhibits the neurospheroidal colony formation and migration of primary glioblastoma cells but has side effects. To enhance the BXR glioblastoma selectivity and cytotoxicity, we chemically modified it at the carboxyl group with either nitroethanolamine (NEA) bearing a NO-donating group (a well-known bioactivity enhancer; BXR-NEA) or with a dopamine (DA) moiety (to represent the highly toxic for various tumor cells N-acyldopamine family; BXR-DA). These two novel compounds were tested in the 2D (monolayer culture) and 3D (multicellular tumor spheroids) in vitro models. Both BXR-DA and BXR-NEA were found to be more toxic for rat C6 and human U-87MG glioma cells than the initial BXR. After 24 h incubation of the cells (monolayer culture) with the drugs, the IC50 values were in the range of 28-42, and 122-152 µM for BXR derivatives and BXR, respectively. The cell death occurred via apoptosis according to the annexin staining and caspase activation. The tumor spheroids demonstrated higher resistance to the treatment compared to that one of the monolayer cultures. BXR-DA and BXR-NEA were more specific against tumor cells than the parental drug, in particular the selectivity index was 1.8-2.7 vs. 1.3-1.5, respectively. Moreover, they inhibited cell migration more effectively than parental BXR according to a scratch assay. Cell spreading from the tumor spheroids was also inhibited. Thus, the obtained BXR derivatives could be promising for glioblastoma treatment.

5-alkylvinyl-1,2,4-triazole nucleosides: Synthesis and biological evaluation.

Some 5-substituted ribavirin analogues have a high antiviral and anticancer activity, but their mechanisms of action are obviously not the same as their parent compound. The SAR studies performed on 3 (5)-substituted 1,2,4-triazole nucleosides have shown a high dependency between the structure of the 3 (5)-substituent and the level of antiviral/anticancer activity. The most active substances of the row contain coplanar with the 1,2,4-triazole ring aromatic substituent which is connected by a rigid ethynyl bond. However, the compounds with the trans-vinyl linker also had antiviral activity. We decided to study the antitumor activity of ribavirin analogues with alkyl/aryl vinyl substituents in the 5th position of the 1,2,4-triazole ring. Protected nucleoside analogues with various 5-alkylvinyl substituents were obtained by Horner-Wadsworth-Emmons reaction from the common precursor and converted to the nucleosides. Arylvinyl nucleosides were synthesised according the reported procedures. All compounds did not show significant antiproliferative activity on several tumour cell lines. Coplanar aromatic motif in the 5-substituent for the anticancer activity manifestation was confirmed.

Arachidonoylcholine and Other Unsaturated Long-Chain Acylcholines Are Endogenous Modulators of the Acetylcholine Signaling System.

Cholines acylated with unsaturated fatty acids are a recently discovered family of endogenous lipids. However, the data on the biological activity of acylcholines remain very limited. We hypothesized that acylcholines containing residues of arachidonic (AA-CHOL), oleic (Ol-CHOL), linoleic (Ln-CHOL), and docosahexaenoic (DHA-CHOL) acids act as modulators of the acetylcholine signaling system. In the radioligand binding assay, acylcholines showed inhibition in the micromolar range of both α7 neuronal nAChR overexpressed in GH4C1 cells and muscle type nAChR from Torpedo californica, as well as Lymnaea stagnalis acetylcholine binding protein. Functional response was checked in two cell lines endogenously expressing α7 nAChR. In SH-SY5Y cells, these compounds did not induce Ca2+ rise, but inhibited the acetylcholine-evoked Ca2+ rise with IC50 9 to 12 µM. In the A549 lung cancer cells, where α7 nAChR activation stimulates proliferation, Ol-CHOL, Ln-CHOL, and AA-CHOL dose-dependently decreased cell viability by up to 45%. AA-CHOL inhibited human erythrocyte acetylcholinesterase (AChE) and horse serum butyrylcholinesterase (BChE) by a mixed type mechanism with Ki = 16.7 ± 1.5 µM and αKi = 51.4 ± 4.1 µM for AChE and Ki = 70.5 ± 6.3 µM and αKi = 214 ± 17 µM for BChE, being a weak substrate of the last enzyme only, agrees with molecular docking results. Thus, long-chain unsaturated acylcholines could be viewed as endogenous modulators of the acetylcholine signaling system.

Phase 1 study of capmatinib in MET-positive solid tumor patients: Dose escalation and expansion of selected cohorts.

Capmatinib is an oral, ATP-competitive, and highly potent, type 1b MET inhibitor. Herein, we report phase 1 dose-escalation results for capmatinib in advanced MET-positive solid tumor patients and dose expansion in advanced non-lung tumors. Capmatinib was well tolerated with a manageable safety profile across all explored doses. Dose-limiting toxicities (DLT) occurred at 200 mg twice daily (bid), 250 mg bid, and 450 mg bid capsules; however, no DLT were reported at 600 mg bid (capsules). Capmatinib tablets at 400 mg bid had comparable tolerability and exposure to that of 600 mg bid capsules. Maximum tolerated dose was not reached; recommended phase 2 dose was 400 mg bid tablets/600 mg bid capsules; at this dose, Ctrough >EC90 (90% inhibition of c-MET phosphorylation in animal models) is expected to be achieved and maintained. Among the dose-expansion patients (N = 38), best overall response across all cohorts was stable disease (gastric cancer 22%, hepatocellular carcinoma 46%, other indications 28%); two other indication patients with gene copy number (GCN) ≥6 achieved substantial tumor reduction. Near-complete immunohistochemically determined phospho-MET inhibition (H-score = 2) was shown following capmatinib 450 mg bid capsule in paired biopsies obtained from one advanced colorectal cancer patient. Incidence of high-level MET GCN (GCN ≥6) and MET-overexpressing (immunohistochemistry 3+) tumors in the expansion cohorts was 8% and 13%, respectively; no MET mutations were observed. Thus, the recommended phase 2 dose (RP2D) of capmatinib was 600 mg bid capsule/400 mg bid tablet. Capmatinib was well tolerated and showed antitumor activity and acceptable safety profile at the RP2D. (ClinicalTrials.gov Identifier: NCT01324479).

Phase Ib/II Study of Capmatinib (INC280) Plus Gefitinib After Failure of Epidermal Growth Factor Receptor (EGFR) Inhibitor Therapy in Patients With EGFR-Mutated, MET Factor-Dysregulated Non-Small-Cell Lung Cancer.

PURPOSE: MET dysregulation occurs in up to 26% of non-small-cell lung cancers (NSCLCs) after epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) treatment. Capmatinib (INC280) is a potent and selective MET inhibitor with preclinical activity in combination with gefitinib in EGFR-mutant, MET-amplified/overexpressing models of acquired EGFR-TKI resistance. This phase Ib/II study investigated the safety and efficacy of capmatinib plus gefitinib in patients with EGFR-mutated, MET-dysregulated (amplified/overexpressing) NSCLC who experienced disease progression while receiving EGFR-TKI treatment. METHODS: Patients in phase Ib received capmatinib 100- to 800-mg capsules once per day or 200- to 600-mg capsules or tablets twice per day, plus gefitinib 250 mg once per day. Patients in phase II received the recommended phase II dose. The primary end point was the overall response rate (ORR) per Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1. RESULTS: Sixty-one patients were treated in phase Ib, and 100 were treated in phase II. The recommended phase II dose was capmatinib 400 mg twice per day plus gefitinib 250 mg once per day. Preliminary clinical activity was observed, with an ORR across phase Ib/II of 27%. Increased activity was seen in patients with high MET-amplified tumors, with a phase II ORR of 47% in patients with a MET gene copy number ≥ 6. Across phases Ib and II, the most common drug-related adverse events were nausea (28%), peripheral edema (22%), decreased appetite (21%), and rash (20%); the most common drug-related grade 3/4 adverse events were increased amylase and lipase levels (both 6%). No significant drug-drug interactions between capmatinib and gefitinib were evident. CONCLUSION: This study, focused on a predominant EGFR-TKI resistance mechanism in patients with EGFR-mutated NSCLC, shows that the combination of capmatinib with gefitinib is a promising treatment for patients with EGFR-mutated, MET-dysregulated NSCLC, particularly MET-amplified disease.

Phase 2 Study of the HSP-90 Inhibitor AUY922 in Previously Treated and Molecularly Defined Patients with Advanced Non-Small Cell Lung Cancer.

INTRODUCTION: In this phase 2 study, we evaluated the activity of AUY922 in pretreated patients with stage IV NSCLC. METHODS: Patients with advanced NSCLC were divided into molecularly defined strata based on mutations in the EGFR gene, the ALK receptor tyrosine kinase gene (ALK), the KRAS gene, or the wild type of all three. All patients must have received more than two prior lines of therapy, except for those in a fifth stratum for a less pretreated EGFR cohort (EGFR<2). In the EGFR-mutant and ALK-rearranged strata, prior platinum therapy was not required. Patients with EGFR mutation must have received an EGFR tyrosine kinase inhibitor unless they had de novo resistance (e.g., T790M or exon 20 insertions). Eligible patients received weekly intravenous AUY922, 70 mg/m2. The primary objective was to estimate efficacy (complete or partial response, or in the absence of complete or partial response, stable disease) at 18 weeks, by the Response Criteria in Solid Tumors. RESULTS: A total of 153 patients from 21 global centers were enrolled from October 2010 to November 2014. The investigator-assessed overall response rate and stable disease rate at 18 weeks were 31.8% and 9.1% in the ALK-rearranged stratum, 17.1% and 8.6% in EGFR-mutant stratum, 9.7% and 22.6% in the EGFR<2 stratum, 0% and 7.1% in KRAS-mutant stratum, and 8.8% and 8.8% in wild-type stratum. Biomarker data showed activity of AUY922 in EGFR-mutant patients with exon 19 deletion, T790M mutation, and exon 20 insertion. The most common (≥40%) all-causality adverse events were diarrhea, nausea, and decreased appetite. Visual-related disorders were reported in 79.7% of patients (most were grade 1/2). Thirty-five patients (22.9%) reported night blindness. CONCLUSION: AUY922 is active in patients with NSCLC, particularly among patients with ALK rearrangements and EGFR mutations.

Ocular toxicity of AUY922 in pigmented and albino rats.

AUY922, a heat shock protein 90 inhibitor is associated with ocular adverse events (AEs). To provide a better understanding of ocular AEs in patients, 4 investigative studies were performed in a step-wise approach to assess retinal structure and function in pigmented (Brown Norway) and albino (Wistar) rats. In rats administered 30mg/kg of AUY922, the AUC0-24h and Cmax are comparable to that in patients at 70mg/m(2). AUY922 at ≥30mg/kg was poorly tolerated by rats with morbidity or mortality generally after the third weekly treatment. Electroretinography (ERG) changes were observed at doses ≥30mg/kg. The ERG changes were dose dependent, consistent with an effect on the photoreceptors, and fully reversible. The ERG effects could not be minimized by decreasing the Cmax while maintaining AUC. Histopathological changes were seen mainly when rats were administered AUY922 at 100mg/kg. The 2-hour infusion of AUY922 at 100mg/kg caused disorganization of the outer segment photoreceptor morphology in male Brown Norway rats; the severity of the disorganization increased with the number of administrations, but was reversible during a 4-week posttreatment period. There was no major difference in ocular response between Brown Norway and Wistar rats. No changes in serum iron levels, and no changes in rhodopsin, PDE6α, ß-transducin concentrations, or retinal pigment epithelium-specific protein RPE65 expression were observed after single and multiple infusions of AUY922 at 100mg/kg compared to vehicle-treated controls. AUY922 retinal toxicity in rats recapitulates and further characterizes that reported in patients and is shown to be reversible, while a precise molecular mechanism for the effect was not determined.

Phase 1B/2 study of the HSP90 inhibitor AUY922 plus trastuzumab in metastatic HER2-positive breast cancer patients who have progressed on trastuzumab-based regimen.

This open-label, multicenter, phase 1B/2 trial assessed AUY922 plus trastuzumab in patients with locally advanced or metastatic HER2-positive breast cancer previously treated with chemotherapy and anti-HER2 therapy. This study was composed of a dose-escalation part with AUY922 administered weekly at escalating doses with trastuzumab 2 mg/kg/week (phase 1B), followed by a phase 2 part using the same regimen at recommended phase 2 dose (RP2D). The primary objectives were to determine the maximum tolerated dose (MTD) and/or RP2D (phase 1B), and to evaluate preliminary antitumor activity (phase 2) of AUY922 plus trastuzumab at MTD/RP2D. Forty-five patients were treated with AUY922 plus trastuzumab (4 in phase 1B with AUY922 at 55 mg/m2 and 41 in phase 1B/2 with AUY922 at 70 mg/m2 [7 in phase 1B and 34 in phase 2]). One patient in phase 1B (70 mg/m2) experienced a dose-limiting toxicity (grade 3 diarrhea); the RP2D was weekly AUY922 70 mg/m2 plus trastuzumab. Of the 41 patients in the 70 mg/m2 cohort, the overall response rate (complete or partial responses) was 22.0% and 48.8% patients had stable disease. Study treatment-related adverse events occurred in 97.8% of patients; of these, 31.1% were grade 3 or 4. Forty-one patients (91.1%) reported ocular events (82.3% had grade 1 or 2 events). Two patients (4.4%) had ocular events leading to the permanent discontinuation of study treatment. AUY922 at 70 mg/m2 plus trastuzumab standard therapy is well tolerated and active in patients with HER2-positive metastatic breast cancer who progressed on trastuzumab-based therapy.

Cytotoxicity of Endogenous Lipids N-acyl Dopamines and their Possible Metabolic Derivatives for Human Cancer Cell Lines of Different Histological Origin.

BACKGROUND/AIM: Dopamine amides of long chain fatty acids are a family of endogenous mammalian lipids with an unknown function; they are anti-proliferative for the C6 glioblastoma cell line. To assess their possible anti-cancer activity we evaluated their cytotoxicity for a set of cancer cell lines. MATERIALS AND METHODS: Anti-proliferative and cytotoxic actions of these substances were evaluated in HOS, IMR-32, MCF-7, Namalwa, K-562 and HEK 293 cell lines (18 h incubation time) using MTT and lactate dehydrogenase (LDH) tests, accordingly. RESULTS: All N-acyl dopamines (NADA) induced cell death in all cell lines tested with a 50% lethal dose (LD50) in the range of 0.5-80 µM, except for HEK-293. For HEK-293 only N-arachidonoyl epinephrine demonstrated an LD50 below 100 µM. CONCLUSION: According to the structure-activity relationship, N-acyl dopamines with an intact catechol group and a non-modified hydrophobic fatty acid residue are cytotoxic to cancer cell lines of various histological origins.