Standard or high dose chemoradiotherapy, with or without the protease inhibitor nelfinavir, in patients with locally advanced pancreatic cancer: The phase 1/randomised phase 2 SCALOP-2 trial.

BACKGROUND: The multi-centre two-stage SCALOP-2 trial (ISRCTN50083238) assessed whether dose escalation of consolidative chemoradiotherapy (CRT) or concurrent sensitization using the protease inhibitor nelfinavir improve outcomes in locally advanced pancreatic cancer (LAPC) following four cycles of gemcitabine/nab-paclitaxel. METHODS: In stage 1, the maximum tolerated dose (MTD) of nelfinavir concurrent with standard-dose CRT (50.4 Gy in 28 fractions) was identified from a cohort of 27 patients. In stage 2, 159 patients were enrolled in an open-label randomized controlled comparison of standard versus high dose (60 Gy in 30 fractions) CRT, with or without nelfinavir at MTD. Primary outcomes following dose escalation and nelfinavir use were respectively overall survival (OS) and progression free survival (PFS). Secondary endpoints included health-related quality of life (HRQoL). RESULTS: High dose CRT did not improve OS (16.9 (60 % confidence interval, CI 16.2-17.7) vs. 15.6 (60 %CI 14.3-18.2) months; adjusted hazard ratio, HR 1.13 (60 %CI 0.91-1.40; p = 0.68)). Similarly, median PFS was not improved by nelfinavir (10.0 (60 %CI 9.9-10.2) vs. 11.1 (60 %CI 10.3-12.8) months; adjusted HR 1.71 (60 %CI 1.38-2.12; p = 0.98)). Local progression at 12 months was numerically lower with high-dose CRT than with standard dose CRT (n = 11/46 (23.9 %) vs. n = 15/45 (33.3 %)). Neither nelfinavir nor radiotherapy dose escalation impacted on treatment compliance or grade 3/4 adverse event rate. There were no sustained differences in HRQoL scores between treatment groups over 28 weeks post-treatment. CONCLUSIONS: Dose-escalated CRT may improve local tumour control and is well tolerated when used as consolidative treatment in LAPC but does not impact OS. Nelfinavir use does not improve PFS.

Predicting immune response targets in orthoflaviviruses through sequence homology and computational analysis.

CONTEXT: Flaviviruses cause severe encephalitic or hemorrhagic diseases in humans. Its members, Kyasanur forest disease virus (KFDV) and Alkhumra hemorrhagic fever virus (ALKV), cause hemorrhagic fever and are prevalent in India and Saudi Arabia, respectively, while the tick-borne encephalitis virus (TBEV) causes a dangerous encephalitic infection in Europe and Asia. However, little information is available about the targets of immune responses for these deadly viruses. Here, we predict potential antigenic peptide epitopes of viral envelope protein for inducing a cell-mediated and humoral immune response. METHODS: Using the Immune Epitope Database and Analysis Resource (IEDB-AR), we identified 13 MHC-I and two MHC-II dominant conserved epitopes in KFDV and ALKV and six MHC-I and three MHC-II epitopes in TBEV envelope proteins. Parallelly, we also predicted B-cell linear and discontinuous envelope protein epitopes for these viruses. Interestingly, the epitopes are conserved in all three viral envelope proteins. Further, the discontinuous epitopes are structurally compared with the available DENV, ZIKV, WNV, TBEV, and LIV envelope protein antibody structures. Overall structural comparison analyses highlight (i) lateral ridge epitope in the ED-III domain of E protein, and (ii) envelope dimer epitope (EDE) could be targeted for developing potent vaccine candidates as well as therapeutic antibody production. Moreover, existing structural and biochemical functions of the same epitopes in homologous viruses are predicted to have a reduced antibody-dependent enhancement (ADE) effect on flaviviral infection.

4″-Alkyl EGCG Derivatives Induce Cytoprotective Autophagy Response by Inhibiting EGFR in Glioblastoma Cells.

Epidermal growth factor receptor (EGFR)-targeted therapy has been proven vital in the last two decades for the treatment of multiple cancer types, including nonsmall cell lung cancer, glioblastoma, breast cancer and head and neck squamous cell carcinoma. Unfortunately, the majority of approved EGFR inhibitors fall into the drug resistance category because of continuous mutations and acquired resistance. Recently, autophagy has surfaced as one of the emerging underlying mechanisms behind resistance to EGFR-tyrosine kinase inhibitors (TKIs). Previously, we developed a series of 4″-alkyl EGCG (4″-Cn EGCG, n = 6, 8, 10, 12, 14, 16, and 18) derivatives with enhanced anticancer effects and stability. Therefore, the current study hypothesized that 4″-alkyl EGCG might induce cytoprotective autophagy upon EGFR inhibition, and inhibition of autophagy may lead to improved cytotoxicity. In this study, we have observed growth inhibition and caspase-3-dependent apoptosis in 4″-alkyl EGCG derivative-treated glioblastoma cells (U87-MG). We also confirmed that 4″-alkyl EGCG could inhibit EGFR in the cells, as well as mutant L858R/T790M EGFR, through an in vitro kinase assay. Furthermore, we have found that EGFR inhibition with 4″-alkyl EGCG induces cytoprotective autophagic responses, accompanied by the blockage of the AKT/mTOR signaling pathway. In addition, cytotoxicity caused by 4″-C10 EGCG, 4″-C12 EGCG, and 4″-C14 EGCG was significantly increased after the inhibition of autophagy by the pharmacological inhibitor chloroquine. These findings enhance our understanding of the autophagic response toward EGFR inhibitors in glioblastoma cells and suggest a potent combinatorial strategy to increase the therapeutic effectiveness of EGFR-TKIs.

Computational insights into VacA toxin inhibition: harnessing FDA-approved antibiotics against Helicobacter pylori.

Cancer is a condition in which a few of the body's cells grow beyond its control and spread to other outward regions. Globally, gastric cancer (GC) is third most common cause of cancer-related mortality and the fourth most common kind of cancer. Persistent infection of VacA-positive Helicobacter pylori (H. pylori) modulates cellular physiology and leads to GC. About ∼70% of H. pylori are positive for vacuolating cytotoxin-A (VacA), and it infects ∼80-90% of world populations. Herein, for first time, we repurposed FDA-approved gram-negative antibiotics, which are feasible alternatives to existing regimens and may be used in combinatorial treatment against VacA-positive H. pylori. Out of 110 FDA-approved antibiotics, we retrieved 92 structures, which were screened against the VacA protein. Moreover, we determined that the top eight hit antibiotics viz; cefpiramide, cefiderocol, eravacycline, doxycycline, ceftriaxone, enoxacin, tedizolid, and cefamandole show binding free energies of -9.1, -8.9, -8.1, -8.0, -7.9, -7.8, -7.8 and -7.8 Kcal/mol, respectively, with VacA protein. Finally, we performed 100 ns duplicate MD simulations on the top eight selected antibiotics showing strong VacA binding. Subsequently, five antibiotics, including cefiderocol, cefpiramide, doxycycline, enoxacin, and tedizolid show stable ligand protein distance and good binding affinity revealed by the MM-PBSA scheme. Among the five antibiotics cefiderocol act as the most potent inhibitor (-28.33 kcal/mol). Furthermore, we also identified the hotspot residue like Asn-506, Tyr-529, and Phe-483 which control the interaction. Concisely, we identified antibiotics that can be repurposed against VacA of H. pylori and explored their molecular mechanism of interaction with VacA.Communicated by Ramaswamy H. Sarma.

Trimodality therapy versus perioperative chemotherapy in the management of locally advanced adenocarcinoma of the oesophagus and oesophagogastric junction (Neo-AEGIS): an open-label, randomised, phase 3 trial.

BACKGROUND: The optimum curative approach to adenocarcinoma of the oesophagus and oesophagogastric junction is unknown. We aimed to compare trimodality therapy (preoperative radiotherapy with carboplatin plus paclitaxel [CROSS regimen]) with optimum contemporaneous perioperative chemotherapy regimens (epirubicin plus cisplatin or oxaliplatin plus fluorouracil or capecitabine [a modified MAGIC regimen] before 2018 and fluorouracil, leucovorin, oxaliplatin, and docetaxel [FLOT] subsequently). METHODS: Neo-AEGIS (CTRIAL-IE 10-14) was an open-label, randomised, phase 3 trial done at 24 centres in Europe. Patients aged 18 years or older with clinical tumour stage T2-3, nodal stage N0-3, and M0 adenocarcinoma of the oesophagus and oesophagogastric junction were randomly assigned to perioperative chemotherapy (three preoperative and three postoperative 3-week cycles of intravenous 50 mg/m2 epirubicin on day 1 plus intravenous 60 mg/m2 cisplatin or intravenous 130 mg/m2 oxaliplatin on day 1 plus continuous infusion of 200 mg/m2 fluorouracil daily or oral 625 mg/m2 capecitabine twice daily up to 2018, with four preoperative and four postoperative 2-week cycles of 2600 mg/m2 fluorouracil, 85 mg/m2 oxaliplatin, 200 mg/m2 leucovorin, and 50 mg/m2 docetaxel intravenously on day 1 as an option from 2018) or trimodality therapy (41·4 Gy in 23 fractions on days 1-5, 8-12, 15-19, 22-26, and 29-31 with intravenous area under the curve 2 mg/mL per min carboplatin plus intravenous 50 mg/m2 paclitaxel on days 1, 8, 15, 22, and 29). The primary endpoint was overall survival, assessed in all randomly assigned patients who received at least one dose of study drug, regardless of which study drug they received, by intention to treat. Secondary endpoints were disease-free survival, site of treatment failure, operative complications, toxicity, pathological response (complete [ypT0N0] and major [tumour regression grade 1 and 2]), margin-free resection (R0), and health-related quality of life. Toxicity and safety data were analysed in the safety population, defined as patients who took at least one dose of study drug, according to treatment actually received. The initial power calculation was based on superiority of trimodality therapy (n=366 patients); it was adjusted after FLOT became an option to a non-inferiority design with a margin of 5% for perioperative chemotherapy (n=540). This study is registered with ClinicalTrials.gov, NCT01726452. FINDINGS: Between Jan 24, 2013, and Dec 23, 2020, 377 patients were randomly assigned, of whom 362 were included in the intention-to treat population (327 [90%] male and 360 [99%] White): 184 in the perioperative chemotherapy group and 178 in the trimodality therapy group. The trial closed prematurely in December, 2020, after the second interim futility analysis (143 deaths), on the basis of similar survival metrics and the impact of the COVID-19 pandemic. At a median follow-up of 38·8 months (IQR 16·3-55·1), median overall survival was 48·0 months (95% CI 33·6-64·8) in the perioperative chemotherapy group and 49·2 months (34·8-74·4) in the trimodality therapy group (3-year overall survival 55% [95% CI 47-62] vs 57% [49-64]; hazard ratio 1·03 [95% CI 0·77-1·38]; log-rank p=0·82). Median disease-free survival was 32·4 months (95% CI 22·8-64·8) in the perioperative chemotherapy group and 24·0 months (18·0-40·8) in the trimodality therapy group [hazard ratio 0·89 [95% CI 0·68-1·17]; log-rank p=0·41). The pattern of recurrence, locoregional or systemic, was not significantly different (odds ratio 1·35 [95% CI 0·63-2·91], p=0·44). Pathological complete response (odds ratio 0·33 [95% CI 0·14-0·81], p=0·012), major pathological response (0·21 [0·12-0·38], p<0·0001), and R0 rates (0·21 [0·08-0·53], p=0·0003) favoured trimodality therapy. The most common grade 3-4 adverse event was neutropenia (49 [27%] of 183 patients in the perioperative chemotherapy group vs 11 [6%] of 178 patients in the trimodality therapy group), followed by diarrhoea (20 [11%] vs none), and pulmonary embolism (ten [5%] vs nine [5%]). One (1%) patient in the perioperative chemotherapy group and three (2%) patients in the trimodality therapy group died from serious adverse events, two (one in each group) of which were possibly related to treatment. No differences were seen in operative mortality (five [3%] deaths in the perioperative chemotherapy group vs four [2%] in the trimodality therapy group), major morbidity, or in global health status at 1 and 3 years. INTERPRETATION: Although underpowered and incomplete, Neo-AEGIS provides the largest comprehensive randomised dataset for patients with adenocarcinoma of the oesophagus and oesophagogastric junction treated with perioperative chemotherapy (predominantly the modified MAGIC regimen), and CROSS trimodality therapy, and reports similar 3-year survival and no major differences in operative and health-related quality of life outcomes. We suggest that these data support continued clinical equipoise. FUNDING: Health Research Board, Cancer Research UK, Irish Cancer Society, Oesophageal Cancer Fund, and French National Cancer Institute.

Withania somnifera extract reduces gastric cancerous properties through inhibition of gankyrin in cellular milieu produced by Helicobacter pylori and Epstein Barr virus.

Helicobacter pylori and Epstein Barr virus (EBV) are group1 carcinogens and their role in Gastric cancer (GC) is well established. Previously we have shown that H. pylori and EBV appears to support aggressive gastric oncogenesis through the upregulation of oncoprotein Gankyrin. Natural plant active molecules have the potential to interrupt oncogenesis. Herein, we investigated the potential of Withania somnifera root extract (WSE) as a possible chemotherapeutic agent against host oncoprotein Gankyrin whose expression was altered by H. pylori and EBV-associated modified cellular milieu. The results show that WSE does not have any inhibitory effect on H. pylori and EBV-associated gene transcripts except for the lmps (lmp1, lmp2a, and lmp2B). Moreover, the WSE exert their anticancer activity via host cellular response and decreased the expression of cell-migratory (mmp3 and mmp7); cell-cycle regulator (pcna); antiapoptotic gene (bcl2); increased the expression of the proapoptotic gene (apaf1 and bax); and tumor suppressor (p53, prb, and pten). Knockdown of Gankyrin followed by the treatment of WSE also decreases the expression of TNF-ɑ, Akt, and elevated the expression of NFkB, PARP, Casp3, and Casp9. WSE also reduces cell migration, and genomic instability and forced the cells to commit programmed cell death. Moreover, molecular simulation studies revealed that out of eight active compounds of WSE, only four compounds such as withaferin A (WFA), withanoside IV (WA4), withanolide B (WNB), and withanolide D (WND) showed direct stable interaction with Gankyrin. This article reports for the first time that treatment of WSE decreased the cancerous properties through host cellular response modulation in gastric epithelial cells coinfected with H. pylori and EBV.Communicated by Ramaswamy H. Sarma.

Efficacy of early PET-CT directed switch to carboplatin and paclitaxel based definitive chemoradiotherapy in patients with oesophageal cancer who have a poor early response to induction cisplatin and capecitabine in the UK: a multi-centre randomised controlled phase II trial.

Background: The utility of early metabolic response assessment to guide selection of the systemic component of definitive chemoradiotherapy (dCRT) for oesophageal cancer is uncertain. Methods: In this multi-centre, randomised, open-label, phase II substudy of the radiotherapy dose-escalation SCOPE2 trial we evaluated the role of 18F-Fluorodeoxyglucose positron emission tomography (PET) at day 14 of cycle 1 of three-weekly induction cis/cap (cisplatin (60 mg/m2)/capecitabine (625 mg/m2 days 1-21)) in patients with oesophageal squamous cell carcinoma (OSCC) or adenocarcinoma (OAC). Non-responders, who had a less than 35% reduction in maximum standardised uptake value (SUVmax) from pre-treatment baseline, were randomly assigned to continue cis/cap or switch to car/pac (carboplatin AUC 5/paclitaxel 175 mg/m2) for a further induction cycle, then concurrently with radiotherapy over 25 fractions. Responders continued cis/cap for the duration of treatment. All patients (including responders) were randomised to standard (50Gy) or high (60Gy) dose radiation as part of the main study. Primary endpoint for the substudy was treatment failure-free survival (TFFS) at week 24. The trial was registered with International Standard Randomized Controlled Trial Number 97125464 and ClinicalTrials.govNCT02741856. Findings: This substudy was closed on 1st August 2021 by the Independent Data Monitoring Committee on the grounds of futility and possible harm. To this point from 22nd November 2016, 103 patients from 16 UK centres had participated in the PET-CT substudy; 63 (61.2%; 52/83 OSCC, 11/20 OAC) of whom were non-responders. Of these, 31 were randomised to car/pac and 32 to remain on cis/cap. All patients were followed up until at least 24 weeks, at which point in OSCC both TFFS (25/27 (92.6%) vs 17/25 (68%); p = 0.028) and overall survival (42.5 vs. 20.4 months, adjusted HR 0.36; p = 0.018) favoured cis/cap over car/pac. There was a trend towards worse survival in OSCC + OAC cis/cap responders (33.6 months; 95%CI 23.1-nr) vs. non-responders (42.5 (95%CI 27.0-nr) months; HR = 1.43; 95%CI 0.67-3.08; p = 0.35). Interpretation: In OSCC, early metabolic response assessment is not prognostic for TFFS or overall survival and should not be used to personalise systemic therapy in patients receiving dCRT. Funding: Cancer Research UK.

Neoadjuvant Management of Adenocarcinoma of the Esophagus and Esophagogastric Junction: Review of Randomized Evidence and Definition of Optimum Treatment Algorithm.

BACKGROUND: Neoadjuvant chemotherapy (nCT) or chemoradiotherapy (nCRT) are accepted standards of care for the management of adenocarcinoma of the esophagus and gastroesophageal junction. SUMMARY: The MRC-OEO2 study established the role of 2 cycles of neoadjuvant cisplatin/fluoropyrimidine. More recently, the FLOT-AIO4 study demonstrated the superiority of perioperative FLOT chemotherapy (5FU, oxaliplatin, and docetaxel) compared to ECX (epirubicin, cisplatin, and capecitabine) regime. The results from the pivotal CROSS study established neoadjuvant CRT as a new standard of care in OG cancer. The survival benefits observed in FLOT and CROSS studies are similar [FLOT - hazard ratio 0.75 (0.62-0.92); CROSS - 0.741 (0.55-0.98)]. KEY MESSAGES: Both nCT and nCRT have been shown to be associated with survival benefit compared to surgery alone. We have performed a comprehensive review of the available evidence to define the optimum treatment algorithm and identify specific patient sub-groups who may be appropriate for the use of one or more of these neoadjuvant options.

Long-Range Magnetic Order in Nickel Hydroxide-Functionalized Graphene Quantum Dots.

In this work, we demonstrate the prospect of chemically synthesizing transition metal (Ni) doped magnetic graphene quantum dots (GQDs) with the sole aim of shedding light on their magnetic properties. Our results show that adsorption of nickel hydroxide on predominantly paramagnetic GQDs reveals antiferromagnetic ordering in the M-T profile around 10 K with change of the spin exchange coupling deviating from J = 1/2 to J = 1, mainly arising from the d-p mixing hybridization between the p orbital of carbon from the GQD and the d orbital of Ni. Furthermore, our results are well complemented by ab initio simulations showing asymmetry of the up and down spins around the Fermi level for nickel hydroxide-doped GQDs with long-range spin polarization. Furthermore, the magnitude of the net magnetic moment generated for doped GQDs on the carbon atoms is found to be site-dependent (surface or edge).

Use of a non-endoscopic immunocytological device (Cytosponge™) for post chemoradiotherapy surveillance in patients with oesophageal cancer in the UK (CYTOFLOC): A multicentre feasibility study.

Background: Effective surveillance strategies are required for patients diagnosed with oesophageal squamous cell carcinoma (OSCC) or adenocarcinoma (OAC) for whom chemoradiotherapy (CRT) is used as a potentially-curative, organ-sparing, alternative to surgery. In this study, we evaluated the safety, acceptability and tolerability of a non-endoscopic immunocytological device (the Cytosponge™) to assess treatment response following CRT. Methods: This multicentre, single-arm feasibility trial took place in 10 tertiary cancer centres in the UK. Patients aged at least 16 years diagnosed with OSCC or OAC, and who were within 4-16 weeks of completing definitive or neo-adjuvant CRT, were included. Participants were required to have a Mellow-Pinkas dysphagia score of 0-2 and be able to swallow tablets. All patients underwent a single Cytosponge™ assessment in addition to standard of care (which included post-treatment endoscopic evaluation with biopsy for patients undergoing definitive CRT; surgery for those who received neo-adjuvant CRT). The primary outcome was the proportion of consented, evaluable patients who successfully underwent Cytosponge™ assessment. Secondary and tertiary outcomes included safety, study consent rate, acceptance rate, the suitability of obtained samples for biomarker analysis, and the comparative efficacy of Cytosponge™ to standard histology (endoscopy and biopsy or post-resection specimen) in assessing for residual disease. The trial is registered with ClinicalTrials.gov, NCT03529669. Findings: Between 18th April 2018 and 16th January 2020, 41 (42.7%; 95% confidence interval (CI) 32.7-53.2) of 96 potentially eligible patients consented to participate. Thirty-nine (95.1%, 95% CI 83.5-99.4) successfully carried out the Cytosponge™ procedure. Of these, 37 (95%) would be prepared to repeat the procedure. There were only two grade 1 adverse events attributed to use of the Cytosponge™. Thirty-five (90%) of the completed Cytosponge™ samples were suitable for biomarker analysis; 29 (83%) of these were concordant with endoscopic biopsies, three (9%) had findings suggestive of residual cancer on Cytosponge™ not found on endoscopic biopsies, and three (9%) had residual cancer on endoscopic biopsies not detected by Cytosponge™. Interpretation: Use of the CytospongeTM is safe, tolerable, and acceptable for the assessment of treatment response following CRT in OAC and OSCC. Further evaluation of Cytosponge™ in this setting is warranted. Funding: Cancer Research UK, National Institute for Health Research, Medical Research Council.

Development and validation of prognostic models for anal cancer outcomes using distributed learning: protocol for the international multi-centre atomCAT2 study.

BACKGROUND: Anal cancer is a rare cancer with rising incidence. Despite the relatively good outcomes conferred by state-of-the-art chemoradiotherapy, further improving disease control and reducing toxicity has proven challenging. Developing and validating prognostic models using routinely collected data may provide new insights for treatment development and selection. However, due to the rarity of the cancer, it can be difficult to obtain sufficient data, especially from single centres, to develop and validate robust models. Moreover, multi-centre model development is hampered by ethical barriers and data protection regulations that often limit accessibility to patient data. Distributed (or federated) learning allows models to be developed using data from multiple centres without any individual-level patient data leaving the originating centre, therefore preserving patient data privacy. This work builds on the proof-of-concept three-centre atomCAT1 study and describes the protocol for the multi-centre atomCAT2 study, which aims to develop and validate robust prognostic models for three clinically important outcomes in anal cancer following chemoradiotherapy. METHODS: This is a retrospective multi-centre cohort study, investigating overall survival, locoregional control and freedom from distant metastasis after primary chemoradiotherapy for anal squamous cell carcinoma. Patient data will be extracted and organised at each participating radiotherapy centre (n = 18). Candidate prognostic factors have been identified through literature review and expert opinion. Summary statistics will be calculated and exchanged between centres prior to modelling. The primary analysis will involve developing and validating Cox proportional hazards models across centres for each outcome through distributed learning. Outcomes at specific timepoints of interest and factor effect estimates will be reported, allowing for outcome prediction for future patients. DISCUSSION: The atomCAT2 study will analyse one of the largest available cross-institutional cohorts of patients with anal cancer treated with chemoradiotherapy. The analysis aims to provide information on current international clinical practice outcomes and may aid the personalisation and design of future anal cancer clinical trials through contributing to a better understanding of patient risk stratification.

Role of Doxorubicin on the Loading Efficiency of ICG within Silk Fibroin Nanoparticles.

The effective loading or encapsulation of multimodal theranostic agents within a nanocarrier system plays an important role in the clinical development of cancer therapy. In recent years, the silk fibroin protein-based delivery system has been drawing significant attention to be used in nanomedicines due to its biocompatible and biodegradable nature. In this study, silk fibroin nanoparticles (SNPs) have been synthesized by a novel and cost-effective ultrasonic atomizer-based technique for the first time. The fabricated SNPs were coencapsulated by the FDA-approved indocyanine green (ICG) dye and the chemotherapeutic drug doxorubicin (DOX). The synthesized SNPs are spherical, with an average diameter of ∼37 ± 4 nm, and the ICG-DOX-coencapsulated SNPs (ID-SNPs) have a diameter size of ∼47 ± 6 nm. For the first time, here we demonstrate that DOX helps in the higher loading of ICG within the ID-SNPs, which enhances the encapsulation efficiency of ICG by ∼99%. This could be attributed to the interaction of ICG and DOX molecules with the silk fibroin protein, which helps ICG to get loaded more efficiently within these nanoparticles. The overall finding of this study suggests that the ID-SNPs could be utilized for enhanced ICG-complemented multimodal deep-tissue bioimaging and synergistic chemo-photothermal therapy.

Structure-based design and synthesis of a novel long-chain 4''-alkyl ether derivative of EGCG as potent EGFR inhibitor: in vitro and in silico studies.

Herein, we report the discovery of a novel long-chain ether derivative of (-)-epigallocatechin-3-gallate (EGCG), a major green tea polyphenol as a potent EGFR inhibitor. A series of 4''-alkyl EGCG derivatives have been synthesized via regio-selectively alkylating the 4'' hydroxyl group in the D-ring of EGCG and tested for their antiproliferative activities against high (A431), moderate (HeLa), and low (MCF-7) EGFR-expressing cancer cell lines. The most potent compound, 4''-C14 EGCG showed the lowest IC50 values across all the tested cell lines. 4''-C14 EGCG was also found to be significantly more stable than EGCG under physiological conditions (PBS at pH 7.4). Further western blot analysis and imaging data revealed that 4''-C14 EGCG induced cell death in A431 cells with shrunken nuclei, nuclear fragmentation, membrane blebbing, and increased population of apoptotic cells where BAX upregulation and BCLXL downregulation were observed. In addition, autophosphorylation of EGFR and its downstream signalling proteins Akt and ERK were markedly inhibited by 4''-C14 EGCG. MD simulation and the MM/PBSA analysis disclosed the binding mode of 4''-C14 EGCG in the ATP-binding site of EGFR kinase domain. Taken together, our findings demonstrate that 4''-C14 EGCG can act as a promising potent EGFR inhibitor with enhanced stability.

Comparative Structural Dynamics of Isoforms of Helicobacter pylori Adhesin BabA Bound to Lewis b Hexasaccharide via Multiple Replica Molecular Dynamics Simulations.

BabA of Helicobacter pylori is the ABO blood group antigen-binding adhesin. Despite considerable diversity in the BabA sequence, it shows an extraordinary adaptation in attachment to mucosal layers. In the current study, multiple replica molecular dynamics simulations were conducted in a neutral aqueous solution to elucidate the conformational landscape of isoforms of BabA bound to Lewis b (Leb) hexasaccharide. In addition, we also investigated the underlying molecular mechanism of the BabA-glycan complexation using the MM/GBSA scheme. The conformational dynamics of Leb in the free and protein-bound states were also studied. The carbohydrate-binding site across the four isoforms was examined, and the conformational variability of several vital loops was observed. The cysteine-cysteine loops and the two diversity loops (DL1 and DL2) were identified to play an essential role in recognizing the glycan molecule. The flexible crown region of BabA was stabilized after association with Leb. The outward movement of the DL2 loop vanished upon ligand binding for the Spanish specialist strain (S381). Our study revealed that the S831 strain shows a stronger affinity to Leb than other strains due to an increased favorable intermolecular electrostatic contribution. Furthermore, we showed that the α1-2-linked fucose contributed most to the binding by forming several hydrogen bonds with key amino acids. Finally, we studied the effect of the acidic environment on the BabA-glycan complexation via constant pH MD simulations, which showed a reduction in the binding free energy in the acidic environment. Overall, our study provides a detailed understanding of the molecular mechanism of Leb recognition by four isoforms of H. pylori that may help the development of therapeutics targeted at inhibiting H. pylori adherence to the gastric mucosa.

Exploring hypoxic biology to improve radiotherapy outcomes.

Ionising radiotherapy is a well-established, effective cancer treatment modality, whose efficacy has improved with the application of newer technological modalities. However, patient outcomes are governed and potentially limited by aspects of tumour biology that are associated with radioresistance. Patients also still endure treatment-associated toxicities owed to the action of ionising radiation in normoxic tissue adjacent to the tumour mass. Tumour hypoxia is recognised as a key component of the tumour microenvironment and is well established as leading to therapy resistance and poor prognosis. In this review, we outline the current understanding of hypoxia-mediated radiotherapy resistance, before exploring targeting tumour hypoxia for radiotherapy sensitisation to improve treatment outcomes and increase the therapeutic window. This includes increasing oxygen availability in solid tumours, the use of hypoxia-activated prodrugs, targeting of hypoxia-regulated or associated signalling pathways, as well as the use of high-LET radiotherapy modalities. Ultimately, targeting hypoxic radiobiology combined with precise radiotherapy delivery modalities and modelling should be associated with improvement to patient outcomes.

Finding potent inhibitors against SARS-CoV-2 main protease through virtual screening, ADMET, and molecular dynamics simulation studies.

Currently, no antiviral drug or vaccine is available to treat COVID-19 caused by SARS-CoV-2. This underscores an urgent need for developing a drug against SARS-CoV-2. The main protease (3CLpro) of SARS-CoV-2 is considered an essential protein for maintaining the viral life cycle and, therefore, a potential target for drug development. In a recent study, 1000 potential ligands were identified for 3CLpro by screening 1.3 billion compounds from the ZINC15 library. In the current study, we have further screened these 1000 compounds using structure-based virtual screening utilizing the Schrödinger suite and identified nine compounds having a docking score of ∼ -11.0 kcal/mol or less. The top 5 hits display good pharmacological profiles revealing better absorption, proper permeability across the membrane, uniform distribution, and non-toxic. The molecular docking study is further complemented by molecular dynamics simulations of the top 5 docked complexes. The binding free energy analyses via the molecular mechanics generalized Born surface area (MM/GBSA) scheme reveals that ZINC000452260308 is the most potent (ΔGbind = -14.31 kcal/mol) inhibitor. The intermolecular van der Waals interactions mainly drive the 3CLpro-ligand association. This new compound may have great potential as a lead molecule to develop a new antiviral drug to fight against COVID-19.Communicated by Ramaswamy H. Sarma.

Unraveling the Molecular Mechanism of Recognition of Human Interferon-Stimulated Gene Product 15 by Coronavirus Papain-Like Proteases: A Multiscale Simulation Study.

The papain-like protease (PLpro) of the coronavirus (CoV) family plays an essential role in processing the viral polyprotein and immune evasion. Additional proteolytic activities of PLpro include deubiquitination and deISGylation, which can reverse the post-translational modification of cellular proteins conjugated with ubiquitin or (Ub) or Ub-like interferon-stimulated gene product 15 (ISG15). These activities regulate innate immune responses against viral infection. Thus, PLpro is a potential antiviral target. Here, we have described the structural and energetic basis of recognition of PLpro by the human ISG15 protein (hISG15) using atomistic molecular dynamics simulation across the CoV family, i.e., MERS-CoV (MCoV), SARS-CoV (SCoV), and SARS-CoV-2 (SCoV2). The cumulative simulation length for all trajectories was 32.0 µs. In the absence of the complete crystal structure of complexes, protein-protein docking was used. A mutation (R167E) was introduced across all three PLpro to study the effect of mutation on the protein-protein binding. Our study reveals that the apo-ISG15 protein remains closed while it adopts an open conformation when bound to PLpro, although the degree of openness varies across the CoV family. The binding free energy analysis suggests that hISG15 binds more strongly with SCoV2-PLpro compared to SCoV or MCoV. The intermolecular electrostatic interaction drives the hISG15-PLpro complexation. Our study showed that SCoV or MCoV-PLpro binds more strongly with the C-domain of hISG15, while SCoV2-PLpro binds more favorably the N-domain of hISG15. Overall, our study explains the molecular basis of differential deISGylating activities of PLpro among the CoV family and the specificity of SCoV2-PLpro toward hISG15.

CDPKs: The critical decoders of calcium signal at various stages of malaria parasite development.

Calcium ions are used as important signals during various physiological processes. In malaria parasites, Plasmodium spp., calcium dependent protein kinases (CDPKs) have acquired the unique ability to sense and transduce calcium signals at various critical steps during the lifecycle, either through phosphorylation of downstream substrates or mediating formation of high molecular weight protein complexes. Calcium signaling cascades establish important crosstalk events with signaling pathways mediated by other secondary messengers such as cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP). CDPKs play critical roles at various important physiological steps during parasite development in vertebrates and mosquitoes. They are also important for transmission of the parasite between the two hosts. Combined with the fact that CDPKs are not present in humans, they continue to be pursued as important targets for development of anti-malarial drugs.

Oxaliplatin/capecitabine or carboplatin/paclitaxel-based preoperative chemoradiation for resectable oesophageal adenocarcinoma (NeoSCOPE): Long-term results of a randomised controlled trial.

AIM: This is the first randomised study to evaluate toxicity and survival outcomes of two neoadjuvant chemoradiotherapy (CRT) regimens for patients with localised oesophageal adenocarcinoma (OAC) or gastro-oesophageal junction (GOJ) adenocarcinoma. The initial results showed comparable toxicity between regimens and pathological complete response (pCR) rate favouring CarPacRT. Herein, we report survival, progression patterns, and long-term toxicity after a median follow-up of 40.7 months. METHODS: NeoSCOPE was an open-label, UK multicentre, randomised, phase II trial. Eighty-five patients with resectable OAC or GOJ adenocarcinoma, ≥cT3 and/or ≥cN1 (TNM v7), suitable for neoadjuvant CRT, were recruited between October 2013 and February 2015. Patients were randomised to OxCapRT (oxaliplatin 85 mg/m2 on Days 1, 15, and 29; capecitabine 625 mg/m2 orally twice daily on days of radiotherapy [RT]) or CarPacRT (carboplatin AUC2; paclitaxel 50 mg/m2 on Days 1, 8, 15, 22, and 29). RT dose was 45 Gy/25 fractions/5 weeks. Both arms received induction chemotherapy (two cycles oxaliplatin 130 mg/m2 on Day 1, capecitabine 625 mg/m2 orally twice daily on Days 1-21) before CRT. Surgery was performed 6-8 weeks after CRT. The primary end-point was pCR. Secondary end-points were toxicity, progression-free survival (PFS), overall survival (OS), and patterns of progression. RESULTS: Eighty-five patients were recruited from 17 UK centres. The median OS was 41.7 months (95% confidence interval [CI] 19.6 to not reached) in the OxCapRT arm and was not reached in the CarPacRT arm (multivariable hazard ratio [HR] = 0.48, 95% CIs: 0.24-0.95, P = 0.035). The median PFS was 32.6 months (95% CIs: 17.1 to not reached) in the OxCapRT arm and was not reached in the CarPacRT arm (multivariable HR = 0.54, 95% CIs: 0.29-1.01, P = 0.053). In both arms, the distant progression was twice as common as locoregional progression. CONCLUSIONS: OS and PFS favoured neoadjuvant CarPacRT over OxCapRT. Distant was more common than locoregional progression; therefore, priority should be given to optimising the systemic treatment component. CLINICAL TRIAL INFORMATION: EudraCT Number: 2012-000640-10; ClinicalTrials.gov: NCT01843829.

Efficacy of Reduced-Intensity Chemotherapy With Oxaliplatin and Capecitabine on Quality of Life and Cancer Control Among Older and Frail Patients With Advanced Gastroesophageal Cancer: The GO2 Phase 3 Randomized Clinical Trial.

Importance: Older and/or frail patients are underrepresented in landmark cancer trials. Tailored research is needed to address this evidence gap. Objective: The GO2 randomized clinical trial sought to optimize chemotherapy dosing in older and/or frail patients with advanced gastroesophageal cancer, and explored baseline geriatric assessment (GA) as a tool for treatment decision-making. Design, Setting, and Participants: This multicenter, noninferiority, open-label randomized trial took place at oncology clinics in the United Kingdom with nurse-led geriatric health assessment. Patients were recruited for whom full-dose combination chemotherapy was considered unsuitable because of advanced age and/or frailty. Interventions: There were 2 randomizations that were performed: CHEMO-INTENSITY compared oxaliplatin/capecitabine at Level A (oxaliplatin 130 mg/m2 on day 1, capecitabine 625 mg/m2 twice daily on days 1-21, on a 21-day cycle), Level B (doses 0.8 times A), or Level C (doses 0.6 times A). Alternatively, if the patient and clinician agreed the indication for chemotherapy was uncertain, the patient could instead enter CHEMO-BSC, comparing Level C vs best supportive care. Main Outcomes and Measures: First, broad noninferiority of the lower doses vs reference (Level A) was assessed using a permissive boundary of 34 days reduction in progression-free survival (PFS) (hazard ratio, HR = 1.34), selected as acceptable by a forum of patients and clinicians. Then, the patient experience was compared using Overall Treatment Utility (OTU), which combines efficacy, toxic effects, quality of life, and patient value/acceptability. For CHEMO-BSC, the main outcome measure was overall survival. Results: A total of 514 patients entered CHEMO-INTENSITY, of whom 385 (75%) were men and 299 (58%) were severely frail, with median age 76 years. Noninferior PFS was confirmed for Levels B vs A (HR = 1.09 [95% CI, 0.89-1.32]) and C vs A (HR = 1.10 [95% CI, 0.90-1.33]). Level C produced less toxic effects and better OTU than A or B. No subgroup benefited from higher doses: Level C produced better OTU even in younger or less frail patients. A total of 45 patients entered the CHEMO-BSC randomization: overall survival was nonsignificantly longer with chemotherapy: median 6.1 vs 3.0 months (HR = 0.69 [95% CI, 0.32-1.48], P = .34). In multivariate analysis in 522 patients with all variables available, baseline frailty, quality of life, and neutrophil to lymphocyte ratio were independently associated with OTU, and can be combined in a model to estimate the probability of different outcomes. Conclusions and Relevance: This phase 3 randomized clinical trial found that reduced-intensity chemotherapy provided a better patient experience without significantly compromising cancer control and should be considered for older and/or frail patients. Baseline geriatric assessment can help predict the utility of chemotherapy but did not identify a group benefiting from higher-dose treatment. Trial Registration: isrctn.org Identifier: ISRCTN44687907.