Glutamine Metabolism Heterogeneity in Glioblastoma Unveils an Innovative Combination Therapy Strategy.

Treatment of glioblastoma multiforme (GBM) remains challenging. Unraveling the orchestration of glutamine metabolism may provide a novel viewpoint on GBM therapy. The study presented a full and comprehensive comprehending of the glutamine metabolism atlas and heterogeneity in GBM for facilitating the development of a more effective therapeutic choice. Transcriptome data from large GBM cohorts were integrated in this study. A glutamine metabolism-based classification was established through consensus clustering approach, and a classifier by LASSO analysis was defined for differentiating the classification. Prognosis, signaling pathway activity, tumor microenvironment, and responses to immune checkpoint blockade (ICB) and small molecular drugs were characterized in each cluster. A combinational therapy of glutaminase inhibitor CB839 with dihydroartemisinin (DHA) was proposed, and the influence on glutamine metabolism, apoptosis, reactive oxygen species (ROS), and migration was measured in U251 and U373 cells. We discovered that GBM presented heterogeneous glutamine metabolism-based clusters, with unique survival outcomes, activity of signaling pathways, tumor microenvironment, and responses to ICB and small molecular compounds. In addition, the classifier could accurately differentiate the two clusters. Strikingly, the combinational therapy of CB839 with DHA synergistically attenuated glutamine metabolism, triggered apoptosis and ROS accumulation, and impaired migrative capacity in GBM cells, demonstrating the excellent preclinical efficacy. Altogether, our findings unveil the glutamine metabolism heterogeneity in GBM and propose an innovative combination therapy of CB839 with DHA for this malignant disease.

The glutaminase inhibitor CB-839 targets metabolic dependencies of JAK2-mutant hematopoiesis in MPN.

ABSTRACT: Hyperproliferation of myeloid and erythroid cells in myeloproliferative neoplasms (MPN) driven by the JAK2-V617F mutation is associated with altered metabolism. Given the central role of glutamine in anabolic and catabolic pathways, we examined the effects of pharmacologically inhibiting glutaminolysis, that is, the conversion of glutamine (Gln) to glutamate (Glu), using CB-839, a small molecular inhibitor of the enzyme glutaminase (GLS). We show that CB-839 strongly reduced the mitochondrial respiration rate of bone marrow cells from JAK2-V617F mutant (VF) mice, demonstrating a marked dependence of these cells on Gln-derived ATP production. Consistently, in vivo treatment with CB-839 normalized blood glucose levels, reduced splenomegaly and decreased erythrocytosis in VF mice. These effects were more pronounced when CB-839 was combined with the JAK1/2 inhibitor ruxolitinib or the glycolysis inhibitor 3PO, indicating possible synergies when cotargeting different metabolic and oncogenic pathways. Furthermore, we show that the inhibition of glutaminolysis with CB-839 preferentially lowered the proportion of JAK2-mutant hematopoietic stem cells (HSCs). The total number of HSCs was decreased by CB-839, primarily by reducing HSCs in the G1 phase of the cell cycle. CB-839 in combination with ruxolitinib also strongly reduced myelofibrosis at later stages of MPN. In line with the effects shown in mice, proliferation of CD34+ hematopoietic stem and progenitor cells from polycythemia vera patients was inhibited by CB-839 at nanomolar concentrations. These data suggest that inhibiting GLS alone or in combination with inhibitors of glycolysis or JAK2 inhibitors represents an attractive new therapeutic approach to MPN.

2-phenylacetamide Separated from the seed of Lepidium apetalum Willd. inhibited renal fibrosis via MAPK pathway mediated RAAS and oxidative stress in SHR Rats.

BACKGROUND: Renal fibrosis with Renin-angiotensin-aldosterone system (RAAS) activation and oxidative stress are one of the major complications in hypertension. 2-phenylacetamide (PA), a major active component of Lepidium apetalum Willd. (L.A), has numerous pharmacological effects. Its analogues have the effect of anti-renal fibrosis and alleviating renal injury. This study aims to explore the underlying mechanism of PA for regulating the renal fibrosis in SHR based on the MAPK pathway mediated RAAS and oxidative stress. METHODS: The SHR rats were used as the hypertension model, and the WKY rats were used as the control group. The blood pressure (BP), urine volume were detected every week. After PA treatment for 4 weeks, the levels of RAAS, inflammation and cytokines were measured by Enzyme-Linked Immunosorbnent Assay (ELISA). Hematoxylin-Eosin staining (HE), Masson and Immunohistochemistry (IHC) were used to observe the renal pathology, collagen deposition and fibrosis. Western blot was used to examine the MAPK pathway in renal. Finally, the SB203580 (p38 MAPK inhibitor) antagonism assay in the high NaCl-induced NRK52e cells was used, together with In-Cell Western (ICW), Flow Cytometry (FCM), High Content Screening (HCS) and ELISA to confirm the potential pharmacological mechanism. RESULTS: PA reduced the BP, RAAS, inflammation and cytokines, promoted the urine, and relieved renal pathological injury and collagen deposition, repaired renal fibrosis, decreased the expression of NADPH Oxidase 4 (NOX4), transforming growth factor-ß (TGF-ß), SMAD3 and MAPK signaling pathway in SHR rats. Meanwhile,,the role of PA could be blocked by p38 antagonist SB203580 effectively in the high NaCl-induced NRK52e cells. Moreover, molecular docking indicated that PA occupied the ligand binding sites of p38 MAPK. CONCLUSION: PA inhibited renal fibrosis via MAPK signalling pathway mediated RAAS and oxidative stress in SHR Rats.

Antagonistic interaction between TTA-A2 and paclitaxel for anti-cancer effects by complex formation with T-type calcium channel.

Studies have shown that in cancer cells, there is an increased T-type calcium channel (TTCC) expression compared to healthy cells. Therefore, the studies targeting TTCC for cancer therapy have shown many positive outcomes. Here, we have used TTA-A2- a potent TTCC inhibitor as a test drug, and paclitaxel (PTX)- a tubule-binding anti-cancer agent as a positive control. Blocking TTCC has shown to overcome resistance in cancer cells towards anti-cancer drugs by reducing calcium influx, and some studies have shown that PTX treatment also reduces the intracellular calcium signaling in cells. So, there is a possibility that PTX might be interacting with calcium channels. Since, drug-drug interaction can cause severe side-effects, or alter the actions of each other; we aim to study the interactions among TTA-A2, PTX, and TTCC. In this study, we have used computational analysis to test the binding of TTA-A2 and PTX with TTCC. To confirm the in-silico result, we further tested these drugs in a 3D spheroid model of A549, a lung adenocarcinoma cell line. The in-silico result showed that both the drugs, TTA-A2 and PTX, could interact at the same site of TTCC to form a higher stable complex as compared to the TTCC-native. The in vitro result showed the antagonistic interaction between the drugs when they are used at the same time. By using the sequential treatment, the spheroids were sensitized by TTA-A2, before treating with PTX. The result indicated that sequential treatment could help to overcome the antagonistic interaction between the two drugs. Communicated by Ramaswamy H. Sarma.

Nepafenac in cataract surgery.

The role of topical non-steroidal anti-inflammatory drugs (NSAIDs) in routine cataract surgery has been established since decades. Topical NSAIDs have been shown to reduce postoperative ocular inflammation and pain, preserve intraoperative mydriasis, and reduce the risk of postoperative cystoid macular oedema, whilst carrying a very low side-effect profile. Nepafenac is one of the currently available topical NSAIDs. The studies have shown that is has a high ocular penetration, allowing for potentially better results than other NSAIDs. This review gathers the current literature on the role of nepafenac in cataract surgery aiming to help surgeons maximise the benefits of its use to achieve improved surgical outcomes.

Nepafenac for cystoid macular oedema secondary to paclitaxel.

Paclitaxel is used to treat a wide range of malignant tumours. This type of drug is known to cause ocular adverse effects, with cystoid macular oedema being a known, but rare complication, of this therapy. Although most cases resolve after discontinuation of the drug, several authors have attempted various treatments to accelerate resolution, or when paclitaxel therapy cannot be discontinued. A case is presented of a 62 year-old man who presented with decreased visual acuity due to bilateral cystoid macular oedema after administration of paclitaxel for oesophageal cancer. As part of the study, optical coherence tomography angiography (OCTA) was performed at the time of diagnosis, and later when the symptoms subsided. Nepafenac eye drops were prescribed as treatment.

Discovery and Characterization of Benzimidazole Derivative XY123 as a Potent, Selective, and Orally Available RORγ Inverse Agonist.

Receptor-related orphan receptor γ (RORγ) has emerged as an attractive therapeutic target for the treatment of cancer and inflammatory diseases. Herein, we report our effort on the discovery, optimization, and evaluation of benzothiazole and benzimidazole derivatives as novel inverse agonists of RORγ. The representative compound 27h (designated as XY123) potently inhibited the RORγ transcription activity with a half-maximal inhibitory concentration (IC50) value of 64 nM and showed excellent selectivity against other nuclear receptors. 27h also potently suppressed cell proliferation, colony formation, and the expression of androgen receptor (AR)-regulated genes in AR-positive prostate cancer cell lines. In addition, 27h demonstrated good metabolic stability and a pharmacokinetic property with reasonable oral bioavailability (32.41%) and moderate half-life (t1/2 = 4.98 h). Significantly, oral administration of compound 27h achieved complete and long-lasting tumor regression in the 22Rv1 xenograft tumor model in mice. Compound 27h may serve as a new valuable lead compound for further development of drugs for the treatment of prostate cancer.

Prostate cancer cells survive anti-androgen and mitochondrial metabolic inhibitors by modulating glycolysis and mitochondrial metabolic activities.

BACKGROUND: Most cancer cells are more glycolytic even under aerobic conditions compared with their normal counterparts. Recent evidence of tumor cell metabolism, however, shows that some tumors also increase mitochondrial oxidative phosphorylation (ox-phos) at some disease states during progression and/or development of drug resistance. Our data show that anti-androgen enzalutamide (ENZA) resistant prostate cancer (PCa) cells use more mitochondrial metabolism leading to higher ox-phos as compared to the ENZA-sensitive cells and can become vulnerable to mitochondrial metabolism targeted therapies. METHODS: Seahorse assay, mass spectrometry and high resolution fluorescence confocal microscopy coupled with image analysis has been used to compare mitochondrial metabolism in ENZA-treated and -untreated anti-androgen-sensitive LNCaP and -resistant C4-2, CWR22ν1, and PCa2b cells. Ex vivo fluorescence microscopy and image analysis has been standardized to monitor mitochondrial electron transport (ETS) activity that likely increases ox-phos in circulating tumor cells (CTCs) isolated fom patients undergoing AR-targeted therapies. RESULTS: Our data show that PCa cells that are resistant to anti-androgen ENZA switch from glycolysis to ox-phos leading to an increased ETS activity. ENZA pretreated cells are more vulnerable to ETS component complex I inhibitor IACS-010759 (IACS) and mitochondrial glutaminase inhibitor CB-839 that reduces glutamate supply to tricarboxylic acid cycle. CTCs isolated from 6 of 20 patient blood samples showed relatively higher ETS activity than the rest of the patients. All six patients have developed ENZA resistance within less than 6 months of the sample collection. CONCLUSION: The enhanced growth inhibitory effects of mitochondrial metabolic inhibitors IACS and CB-839 in ENZA pretreated PCa cells provides a rationale for designing a drug combination trial. Patients can be selected for such trials by monitoring the mitochondrial ETS activities in their CTCs to maximize success.

Enhancing the Efficacy of Glutamine Metabolism Inhibitors in Cancer Therapy.

Glutamine metabolism is reprogrammed during tumorigenesis and has been investigated as a promising target for cancer therapy. However, efforts to drug this process are confounded by the intrinsic metabolic heterogeneity and flexibility of tumors, as well as the risk of adverse effects on the anticancer immune response. Recent research has yielded important insights into the mechanisms that determine the tumor and the host immune responses to pharmacological perturbation of glutamine metabolism. Here, we discuss these findings and suggest that, collectively, they point toward patient stratification and drug combination strategies to maximize the efficacy of glutamine metabolism inhibitors as cancer therapeutics.

Incidence and Outcomes of Cystoid Macular Edema after Descemet Membrane Endothelial Keratoplasty (DMEK) and DMEK Combined with Cataract Surgery.

PURPOSE: To investigate the incidence and outcomes of cystoid macular edema (CME) after Descemet membrane endothelial keratoplasty (DMEK) alone and DMEK combined with cataract surgery (DMEK triple). MATERIALS AND METHODS: A retrospective chart review was performed for patients who underwent DMEK and DMEK triple between January 2014 and March 2018 at two tertiary hospitals. Patients with minimum of 6 months of follow-up were included. Logistic regression analysis was used to identify potential risk factors for CME including gender, age, glaucoma, uveitis, epiretinal membrane, diabetes mellitus, iridotomy, and rebubbling. RESULTS: 09 eyes of 193 patients who underwent DMEK (124 eyes) and DMEK triple (85 eyes) were included. The 6-month incidence of CME was 3.8% (8/209) for all cases, 2.4% (2/85) for DMEK triple, and 4.8% (6/124) for DMEK alone. CME was treated with topical prednisolone acetate 1% and nepafenac four times daily, and/or periocular triamcinolone acetonide, with resolution in all cases. On average, CME was detected 8.9 ± 2.1 weeks postoperatively, with a mean time to resolution of 4.1 ± 1.7 months. The 6-month best-corrected distance visual acuity of eyes that developed CME was not significantly different compared to eyes that did not develop CME (0.17 ± 0.15 logMAR vs. 0.23 ± 0.27 logMAR; p = .76). On logistic regression analysis, no risk factors for developing CME were identified. CONCLUSIONS: The incidence of CME after DMEK was low and not associated with decreased long-term visual acuity. Most cases of CME occurred between 1 and 3 months postoperatively. Predictive factors for CME after DMEK require further study.

T-type calcium channel antagonist, TTA-A2 exhibits anti-cancer properties in 3D spheroids of A549, a lung adenocarcinoma cell line.

AIMS: Despite the advanced cancer treatments, there is increased resistance to chemotherapy and subsequent mortality. In lack of reliable data in monolayer cultures and animal models, researchers are shifting to 3D cancer spheroids, which represents the in vivo robust tumour morphology. Calcium is essential in cell signalling and proliferation. It is found that T-type calcium channels (TTCCs) are overexpressed in various cancer cells, supporting their increased proliferation. Many of the TTCCs blockers available could target other channels besides TTCCs, which can cause adverse effects. Therefore, we hypothesise that TTA-A2, a highly selective blocker towards TTCCs, can inhibit the growth of cancer spheroids, and provide an anti-cancer and an adjuvant role in cancer therapy. METHODS: We studied TTA-A2 and paclitaxel (PTX-control drug) in lung adenocarcinoma cell line- A549, cancer cells and human embryonic kidney cell line- HEK 293, control cell, in their monolayer and spheroids forms for viability, proliferation, morphology change, migration, and invasion-after 48-96 h of treatment. KEY FINDINGS: Though the results varied between the monolayer and spheroids studies, we found both anti-cancer as well as adjuvant effect of TTA-A2 in both the studies. TTA-A2 was able to inhibit the growth, viability, and metastasis of the cancer cells and spheroids. Differences in the results of two modes might explain that why drugs tested successfully in monolayer culture fail in clinical trials. SIGNIFICANCE: This study establishes the role of TTA-A2, a potent TTCC blocker as an anti-cancer and adjuvant drug in reducing the viability and metastasis of the cancer cells.

Comparison of the Effect of Diclofenac 0.1% and Nepafenac 0.1% on Aqueous Flare in Patients Undergoing Cataract Surgery: A Prospective Randomized Study.

OBJECTIVES: To compare, using laser flare meter (LFM), the efficacy of topical nepafenac 0.1, % and diclofenac 0.1% ophthalmic solution in the control of anterior chamber inflammation after uncomplicated cataract surgery. METHODS: Patients undergoing phacoemulsification for age-related cataract were recruited. Complete evaluation with visual acuity, slit-lamp examination, endothelial cell density, intraocular pressure, retinal tomography and anterior chamber flare evaluation was performed before surgery and 1, 15, 30 and 60 days after surgery. Patients were randomly assigned to receive topical diclofenac 0.1% 4 times a day for four weeks or nepafenac 0.1% 3 times a day for three weeks in addition to topical steroids and antibiotic. RESULTS: 64 (31 males, mean age 77.3 ± 5.9) patients were enrolled. Half of them were randomly assigned to group A (diclofenac 0.1%) and half to group B (nepafenac 0.1%). There was a statistically significant visual acuity improvement postoperatively in both groups, with no statistical difference between the groups. Intraocular pressure, corneal thickness, endothelial cells count and macular thickness parameters didn't significantly vary between before and after surgery. One-day after surgery, aqueous flare was significantly higher (22,27 ± 9,25 ph/ms in group A and 22,36 ± 7,47 in group B) than before surgery (14,59 ± 7,16 ph/ms in group A and 11,84 ± 4,44 in group B) in both groups, then declining in the first month and reaching preoperative levels again by 2 months in both groups. In group B, LFM values at 15 and 30 days after surgery were significantly lower (13,59 ± 4,80 and 14,07 ± 5,01) than in group A (17,00 ± 6,97 and 16,96 ± 6,13). CONCLUSIONS: Nepafenac ensured a better inflammation control than diclofenac during the first month.

Targeting glutamine metabolism slows soft tissue sarcoma growth.

Tumour cells frequently utilize glutamine to meet bioenergetic and biosynthetic demands of rapid cell growth. However, glutamine dependence can be highly variable between in vitro and in vivo settings, based on surrounding microenvironments and complex adaptive responses to glutamine deprivation. Soft tissue sarcomas (STSs) are mesenchymal tumours where cytotoxic chemotherapy remains the primary approach for metastatic or unresectable disease. Therefore, it is critical to identify alternate therapies to improve patient outcomes. Using autochthonous STS murine models and unbiased metabolomics, we demonstrate that glutamine metabolism supports sarcomagenesis. STS subtypes expressing elevated glutaminase (GLS) levels are highly sensitive to glutamine starvation. In contrast to previous studies, treatment of autochthonous tumour-bearing animals with Telaglenastat (CB-839), an orally bioavailable GLS inhibitor, successfully inhibits undifferentiated pleomorphic sarcoma (UPS) tumour growth. We reveal glutamine metabolism as critical for sarcomagenesis, with CB-839 exhibiting potent therapeutic potential.

GLS2 is protumorigenic in breast cancers.

Many types of cancers have a well-established dependence on glutamine metabolism to support survival and growth, a process linked to glutaminase 1 (GLS) isoforms. Conversely, GLS2 variants often have tumor-suppressing activity. Triple-negative (TN) breast cancer (testing negative for estrogen, progesterone, and Her2 receptors) has elevated GLS protein levels and reportedly depends on exogenous glutamine and GLS activity for survival. Despite having high GLS levels, we verified that several breast cancer cells (including TN cells) express endogenous GLS2, defying its role as a bona fide tumor suppressor. Moreover, ectopic GLS2 expression rescued cell proliferation, TCA anaplerosis, redox balance, and mitochondrial function after GLS inhibition by the small molecule currently in clinical trials CB-839 or GLS knockdown of GLS-dependent cell lines. In several cell lines, GLS2 knockdown decreased cell proliferation and glutamine-linked metabolic phenotypes. Strikingly, long-term treatment of TN cells with another GLS-exclusive inhibitor bis-2'-(5-phenylacetamide-1,3,4-thiadiazol-2-yl)ethyl sulfide (BPTES) selected for a drug-resistant population with increased endogenous GLS2 and restored proliferative capacity. GLS2 was linked to enhanced in vitro cell migration and invasion, mesenchymal markers (through the ERK-ZEB1-vimentin axis under certain conditions) and in vivo lung metastasis. Of concern, GLS2 amplification or overexpression is linked to an overall, disease-free and distant metastasis-free worse survival prognosis in breast cancer. Altogether, these data establish an unforeseen role of GLS2 in sustaining tumor proliferation and underlying metastasis in breast cancer and provide an initial framework for exploring GLS2 as a novel therapeutic target.

Anti-inflammatory Medication of Cataract Surgery in Pseudoexfoliation Syndrome - NSAID Is Needed.

BACKGROUND: To optimize the anti-inflammatory treatment of cataract surgery in pseudoexfoliation syndrome (PXF) eyes. METHODS: A prospective randomized double-masked trial. Sixty eyes of 60 patients with PXF undergoing routine cataract surgery were randomized for potent topical postoperative anti-inflammatory medication either with prednisolone acetate (10mg/ml), nepafenac (1mg/ml) or their combination. Clinical outcome parameters were recorded at 28 days and 3 months. Recovery from surgery was recorded by a structured home questionnaire. RESULTS: Patient age and gender distribution, and all baseline ophthalmic and surgical parameters were comparable between the study groups. At 28 days, change in central subfield macular thickness was +11.4 ± 11.9 µm in prednisolone acetate group compared to +1.7 ± 16.8 µm in nepafenac (P = .017), and -0.3 ± 8.7 µm in combination therapy (P = .010) groups. At 3 months, the values were +11.8 ± 18.1 µm, +1.8 ± 17.5 µm (P = .055), and -1.3 ± 6.4 µm (P = .055), respectively. Pseudophakic cystoid macular edema (PCME) was reported in two eyes, both with prednisolone acetate monotherapy. After surgery, conjunctival injection lasted 6.5 ± 5.0 days and irritation of the eye 9.5 ± 8.5 days in prednisolone acetate group compared with nepafenac (2.6 ± 2.2 days; P = .037 and 4.3 ± 5.2 days; P = NS, respectively) and combination therapy (3.3 ± 1.9 days; P = NS and 3.0 ± 4.0 days; P = .025, respectively). CONCLUSIONS: Routine cataract surgery of PXF eyes with nonsteroidal anti-inflammatory drugs (NSAID) alone, or in combination with steroids resulted in faster recovery from surgery and avoidance of PCME compared to steroids alone. ABBREVIATIONS: BAB: blood-aqueous barrier; CDVA: corrected distance visual acuity; CDE: cumulative dissipated energy; CSMT: central subfield macular thickness; HRQoL: Health-related quality of life; IOP: intraocular pressure; logMAR: log of the minimum angle of resolution; NSAID: nonsteroidal anti-inflammatory drug; PCME: pseudophakic cystoid macular edema; PXF: pseudoexfoliation syndrome; OCT: optical coherence tomography; t.i.d.: three times a day; VA: visual acuity.

Combined Topical Anti-inflammatory and Oral Acetazolamide in the Treatment of Central Serous Chorioretinopathy.

SIGNIFICANCE: Central serous chorioretinopathy (CSCR) is still a therapeutic challenge with no criterion standard treatment. However, anatomic changes at the level of the retinal pigment epithelium could prove of predictive value in the course of the disease for selective treatment in cases of increased risk of chronicity. PURPOSE: This pilot study analyzes the efficacy for treating acute CSCR with combined systemic acetazolamide 250 mg twice a day and nepafenac 0.1% eye drops three times a day in comparison with an untreated control group. It also evaluates the presence a pigment epithelial detachment (PED) as a risk factor for chronic CSCR. METHODS: Nineteen consecutive patients (group 1) with new or new onset of recurrent CSCR were treated with oral acetazolamide and nepafenac eye drops for at least 2 months. A control group of 14 patients (group 2) with new or new onset of recurrent CSCR were untreated while under regular observation for 4 months. Primary end points were central macular thickness and best-corrected visual acuity after 4 months. Secondary end points were complete regression of subretinal fluid at 3 months and association of PED at baseline with recurrent or chronic CSCR imaged by optical coherence tomography. RESULTS: Group 1 showed significantly faster resolution of subretinal fluid with a mean central macular thickness at 4 months of 271 ± 85 µm compared with 322 ± 79 µm for group 2 (P < .05), but with no functional benefit with a best-corrected visual acuity at 4 months of 0.8 ± 0.2 for group 1 compared with 0.9 ± 0.1 for the control group (P < .05). Patients with a small flat PED were at a higher risk of developing chronic CSCR compared with patients with a dome-shaped or no PED (P < .05). CONCLUSIONS: Central serous chorioretinopathy remains a therapeutic challenge. This pilot study shows faster resolution of subretinal fluid with treatment but without functional benefit compared with observation. The presence of small, flat PED was associated with development of chronic CSCR.

Discovery of 2-(4-Chloro-3-(trifluoromethyl)phenyl)-N-(4-((6,7-dimethoxyquinolin-4-yl)oxy)phenyl)acetamide (CHMFL-KIT-64) as a Novel Orally Available Potent Inhibitor against Broad-Spectrum Mutants of c-KIT Kinase for Gastrointestinal Stromal Tumors.

Starting from our previously developed c-KIT kinase inhibitor CHMFL-KIT-8140, through a type II kinase inhibitor binding element hybrid design approach, we discovered a novel c-KIT kinase inhibitor compound 18 (CHMFL-KIT-64), which is potent against c-KIT wt and a broad spectrum of drug-resistant mutants with improved bioavailability. 18 exhibits single-digit nM potency against c-KIT kinase and c-KIT T670I mutants in the biochemical assay and displays great potencies against most of the gain-of-function mutations in the juxtamembrane domain, drug-resistant mutations in the ATP binding pocket (except V654A), and activation loops (except D816V). In addition, 18 exhibits a good in vivo pharmacokinetic (PK) profile in different species including mice, rats, and dogs. It also displays good in vivo antitumor efficacy in the c-KIT T670I, D820G, and Y823D mutant-mediated mice models as well as in the c-KIT wt patient primary cells which are known to be imatinib-resistant. The potent activity against a broad spectrum of clinically important c-KIT mutants combining the good in vivo PK/pharmacodynamic properties of 18 indicates that it might be a new potential therapeutic candidate for gastrointestinal stromal tumors.

Analgesic Effect of a Single Drop of Nepafenac 0.3% on Pain Associated with Intravitreal Injections: A Randomized Clinical Trial.

PURPOSE: To evaluate the analgesic effect of nepafenac 0.3% in patients undergoing intravitreal injections (IVI) of antivascular endothelial growth factors. METHODS: This is a single-center, prospective, randomized, blinded, triple-arm, placebo-controlled interventional study. Patients were randomized into 3 Groups. Group 1 (n = 33) received nepafenac 0.1%, Group 2 (n = 32) received nepafenac 0.3%, and Group 3 (n = 31) received placebo 40 min before IVI. Using the short form of the McGill Pain Questionnaire (SF-MPQ), pain intensity was assessed with the visual analog scale (VAS), the Main Component of the SF-MPQ, and the present pain intensity (PPI) scores immediately and 6 h postinjection. RESULTS: Immediately after IVI, the VAS pain score was statistically significantly lower in patients treated with nepafenac 0.1% and 0.3%, compared with placebo (P < 0.001 and P = 0.001, respectively). The PPI scores were statistically significantly lower when nepafenac 0.1% or 0.3% was instilled compared with placebo (P = 0.01 and P < 0.0001, respectively). The Main Component of the SF-MPQ scores were statistically significantly lower after nepafenac 0.1% and 0.3% administration compared with placebo (P = 0.001 and P < 0.001, respectively). Six hours post-IVI the nepafenac 0.3% demonstrated statistically significantly higher analgesic effect compared with nepafenac 0.1% and placebo as this was indicated by the VAS pain score (P = 0.013 and P < 0.00001, respectively) and by the PPI score (P = 0.01 and P < 0.00001, respectively). CONCLUSIONS: A single instillation of nepafenac 0.1% or 0.3% before IVI could effectively alleviate the IVI-related pain. The 0.3% formula exerts its analgesic effect more intensively at 6 h after the IVI.

Insight into binding mechanisms of EGFR allosteric inhibitors using molecular dynamics simulations and free energy calculations.

Lung cancer is the leading cause of cancer death, and epidermal growth factor receptor (EGFR) kinase domain mutations are a common cause of non-small-cell lung cancer (NSCLC), a major subtype of lung cancers. Patients harboring most of these mutations respond well to the EGFR inhibitors Gefitinib and Erlotinib initially, but soon develop resistance to them due to the emergence of the gatekeeper mutation T790M. The new-generation inhibitors such as AZD9291, HM61713, CO-1686 and WZ4002 can overcome T790M through covalent binding to Cys 797, but ultimately lose their efficacy upon the emergence of the C797S mutation that abolishes the covalent bonding. Allosteric inhibitors EAI001 and EAI045 are a new type of EGFR inhibitors that bind to EGFR away from the ATP-binding site and not relying on Cys 797. In this study, molecular dynamics simulations and free energy calculations were carried out on EAI001 and EAI045 in complex with EGFR, revealing the detailed inhibitory mechanism of EAI001 and EAI045 as EGFR allosteric inhibitor, which was expected to provide a basis for rational drug design of the EGFR allosteric inhibitors. Communicated by Ramaswamy H. Sarma.

Efficacy of addition of nepafenac 0.1% to steroid eye drops in prevention of post-phaco macular edema in high-risk eyes.

PURPOSE: To compare the efficacy of addition of nonsteroidal anti-inflammatory eye drops to steroidal eye drops with that of using postoperative steroidal anti-inflammatory eye drops alone in prevention of macular edema in high-risk patients. SETTING: Cairo University Hospital. DESIGN: This study was comparative prospective interventional randomized study. METHODS: This study included 100 cataractous eyes divided into five subgroups: 20 eyes of diabetic patients, 20 uveitic eyes, 20 traumatic cataracts, 20 glaucomatous eyes on topical prostaglandin analogs, and 20 eyes with posterior capsular rupture during phacoemulsification. Each subgroup of 20 was randomized between two groups of 10 eyes, group A received postoperative topical steroids alone and group B received both steroidal and nonsteroidal anti-inflammatory eye drops. RESULTS: There was significant increase in postoperative central foveal thickness as compared to preoperative values in both groups (60.9 ± 87.95 µ in group A and 25.52 ± 57.26 µ in group B) that was significantly more in group A (P value 0.016). There was significant difference in postoperative macular thickness between both groups (280.1 ± 86.0 µ and 246.80 ± 57.73 µ, respectively, in groups A and B) (P value = 0.012). There was no statistically significant difference between both groups in preoperative and postoperative corrected distance visual acuity and intraocular pressure. CONCLUSION: Addition of topical nepafenac eye drops to topical steroid drops significantly reduced the amount of pseudophakic macular edema after cataract surgery in high-risk eyes.