Mechanism of Action of the Tumor Vessel Targeting Agent NGR-hTNF: Role of Both NGR Peptide and hTNF in Cell Binding and Signaling

Drug conjugates for the treatment of lung cancer: from drug discovery to clinical practice

A drug conjugate consists of a cytotoxic drug bound via a linker to a targeted ligand, allowing the targeted delivery of the drug to one or more tumor sites. This approach simultaneously reduces drug toxicity and increases efficacy, with a powerful combination of efficient killing and precise targeting. Antibody‒drug conjugates (ADCs) are the best-known type of drug conjugate, combining the specificity of antibodies with the cytotoxicity of chemotherapeutic drugs to reduce adverse reactions by preferentially targeting the payload to the tumor. The structure of ADCs has also provided inspiration for the development of additional drug conjugates. In recent years, drug conjugates such as ADCs, peptide‒drug conjugates (PDCs) and radionuclide drug conjugates (RDCs) have been approved by the Food and Drug Administration (FDA). The scope and application of drug conjugates have been expanding, including combination therapy and precise drug delivery, and a variety of new conjugation technology concepts have emerged. Additionally, new conjugation technology-based drugs have been developed in industry. In addition to chemotherapy, targeted therapy and immunotherapy, drug conjugate therapy has undergone continuous development and made significant progress in treating lung cancer in recent years, offering a promising strategy for the treatment of this disease. In this review, we discuss recent advances in the use of drug conjugates for lung cancer treatment, including structure-based drug design, mechanisms of action, clinical trials, and side effects. Furthermore, challenges, potential approaches and future prospects are presented.

Engineering cytokines for cancer immunotherapy: a systematic review

Cytokines are pivotal mediators of cell communication in the tumor microenvironment. Multiple cytokines are involved in the host antitumor response, but the production and function of these cytokines are usually dysregulated during malignant tumor progression. Considering their clinical potential and the early successful use of cytokines in cancer immunotherapy, such as interferon alpha-2b (IFNα-2b; IntronA^®) and IL-2 (Proleukin^®), cytokine-based therapeutics have been extensively evaluated in many follow-up clinical trials. Following these initial breakthroughs, however, clinical translation of these natural messenger molecules has been greatly limited owing to their high-degree pleiotropic features and complex biological properties in many cell types. These characteristics, coupled with poor pharmacokinetics (a short half-life), have hampered the delivery of cytokines via systemic administration, particularly because of severe dose-limiting toxicities. New engineering approaches have been developed to widen the therapeutic window, prolong pharmacokinetic effects, enhance tumor targeting and reduce adverse effects, thereby improving therapeutic efficacy. In this review, we focus on the recent progress and competitive landscape in cytokine engineering strategies and preclinical/clinical therapeutics for cancer. In addition, aiming to promote engineered cytokine-based cancer immunotherapy, we present a profound discussion about the feasibility of recently developed methods in clinical medicine translation.

Co-delivery of microRNA-150 and quercetin by lipid nanoparticles (LNPs) for the targeted treatment of age-related macular degeneration (AMD)

Age-related macular degeneration (AMD) is characterized by choroidal neovascularization (CNV), which leads to severe vision loss in middle-aged and elderly patients. Current treatments for CNV show weak, transient efficacy, and they can cause several adverse effects. A potential new treatment is to use microRNA-150 (mR150), which regulates physiological and pathological angiogenesis by modulating the expression of CXCR4 at the post-transcriptional level. Here, we developed solid lipid nanoparticles that we modified with an Asp-Gly-Arg peptide to target endothelial cells during abnormal angiogenesis, then we co-loaded them with mR150 and the anti-angiogenic drug quercetin. The resulting nanoparticles had an average size around 200 nm and showed strong ability to target the fundus and inhibit CNV for up to two weeks in a mouse model without causing retinal toxicity. They significantly enhanced the uptake of mR150 in vitro compared to free mR150 or nanoparticles without peptide. Our study suggests that co-administration of mR150 and quercetin has potential for treating age-related macular degeneration and that nanoparticles modified with Asp-Gly-Arg peptide are an effective platform for the co-delivery of small-molecule and nucleic acid drugs via intravitreal injection.

Ameliorating Fibrosis in Murine and Human Tissues with END55, an Endostatin-Derived Fusion Protein Made in Plants

Organ fibrosis, particularly of the lungs, causes significant morbidity and mortality. Effective treatments are needed to reduce the health burden. A fragment of the carboxyl-terminal end of collagen XVIII/endostatin reduces skin and lung fibrosis. This fragment was modified to facilitate its production in plants, which resulted in the recombinant fusion protein, END55. We found that expression of END55 had significant anti-fibrotic effects on the treatment and prevention of skin and lung fibrosis in a bleomycin mouse model. We validated these effects in a second mouse model of pulmonary fibrosis involving inducible, lung-targeted expression of transforming growth factor β1. END55 also exerted anti-fibrotic effects in human lung and skin tissues maintained in organ culture in which fibrosis was experimentally induced. The anti-fibrotic effect of END55 was mediated by a decrease in the expression of extracellular matrix genes and an increase in the levels of matrix-degrading enzymes. Finally, END55 reduced fibrosis in the lungs of patients with systemic sclerosis (SSc) and idiopathic pulmonary fibrosis (IPF) who underwent lung transplantation due to the severity of their lung disease, displaying efficacy in human tissues directly relevant to human disease. These findings demonstrate that END55 is an effective anti-fibrotic therapy in different organs.

In-cell NMR: Why and how?

NMR spectroscopy has been applied to cells and tissues analysis since its beginnings, as early as 1950. We have attempted to gather here in a didactic fashion the broad diversity of data and ideas that emerged from NMR investigations on living cells. Covering a large proportion of the periodic table, NMR spectroscopy permits scrutiny of a great variety of atomic nuclei in all living organisms non-invasively. It has thus provided quantitative information on cellular atoms and their chemical environment, dynamics, or interactions. We will show that NMR studies have generated valuable knowledge on a vast array of cellular molecules and events, from water, salts, metabolites, cell walls, proteins, nucleic acids, drugs and drug targets, to pH, redox equilibria and chemical reactions. The characterization of such a multitude of objects at the atomic scale has thus shaped our mental representation of cellular life at multiple levels, together with major techniques like mass-spectrometry or microscopies. NMR studies on cells has accompanied the developments of MRI and metabolomics, and various subfields have flourished, coined with appealing names: fluxomics, foodomics, MRI and MRS (i.e. imaging and localized spectroscopy of living tissues, respectively), whole-cell NMR, on-cell ligand-based NMR, systems NMR, cellular structural biology, in-cell NMR… All these have not grown separately, but rather by reinforcing each other like a braided trunk. Hence, we try here to provide an analytical account of a large ensemble of intricately linked approaches, whose integration has been and will be key to their success. We present extensive overviews, firstly on the various types of information provided by NMR in a cellular environment (the "why", oriented towards a broad readership), and secondly on the employed NMR techniques and setups (the "how", where we discuss the past, current and future methods). Each subsection is constructed as a historical anthology, showing how the intrinsic properties of NMR spectroscopy and its developments structured the accessible knowledge on cellular phenomena. Using this systematic approach, we sought i) to make this review accessible to the broadest audience and ii) to highlight some early techniques that may find renewed interest. Finally, we present a brief discussion on what may be potential and desirable developments in the context of integrative studies in biology.

Targeting the Blood–Brain Tumor Barrier with Tumor Necrosis Factor-α

The blood–brain tumor barrier represents a major obstacle for anticancer drug delivery to brain tumors. Thus, novel strategies aimed at targeting and breaching this structure are of great experimental and clinical interest. This review is primarily focused on the development and use of a derivative of tumor necrosis factor-α (TNF) that can target and alter the blood–brain-tumor-barrier. This drug, called NGR-TNF, consists of a TNF molecule fused to the Cys-Asn-Gly-Arg-Cys-Gly (CNGRCG) peptide (called NGR), a ligand of aminopeptidase N (CD13)-positive tumor blood vessels. Results of preclinical studies suggest that this peptide-cytokine fusion product represents a valuable strategy for delivering TNF to tumor vessels in an amount sufficient to break the biological barriers that restrict drug penetration in cancer lesions. Moreover, clinical studies performed in patients with primary central nervous system lymphoma, have shown that an extremely low dose of NGR-TNF (0.8 µg/m²) is sufficient to promote selective blood–brain-tumor-barrier alteration, increase the efficacy of R-CHOP (a chemo-immunotherapy regimen) and improve patient survival. Besides reviewing these findings, we discuss the potential problems related to the instability and molecular heterogeneity of NGR-TNF and review the various approaches so far developed to obtain more robust and homogeneous TNF derivatives, as well as the pharmacological properties of other peptide/antibody-TNF fusion products, muteins and nanoparticles that are potentially useful for targeting the blood–brain tumor barrier. Compared to other TNF-related drugs, the administration of extremely low-doses of NGR-TNF or its derivatives appear as promising non-immunogenic approaches to overcome TNF counter-regulatory mechanism and systemic toxicity, thereby enabling safe breaking of the BBTB.

Hepatoprotective effect of Physalis divaricata in paracetamol induced hepatotoxicity: In vitro, in silico and in vivo analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Physalis divaricata D. Don. is an erect weed of family Solanaceae. The root extract of this plant is used by the indigenous communities of Sub-Himalayan region of Uttarakhand, India for the treatment of liver disorders.

AIM OF THE STUDY

To evaluate hepatoprotective potential of P. divaricata in paracetamol (PCM) induced hepatotoxicity in rats.

MATERIALS AND METHODS

The dried roots of P. divaricata were subjected to extraction using different solvents. The chloroform extract, methanol extract and bioactive aqueous fraction of methanol extract were evaluated for hepatoprotective effect. After initial in vitro screening, all extracts were screened for hepatoprotective potential in PCM (3 g/kg p.o) induced hepatotoxicity. Following PCM administration, extracts were administered orally for 7 days in increasing dose concentrations. All the animals were euthanized on eighth day, serum and liver tissues were collected and subjected to various biochemical and histopathological analysis. Aqueous fraction of methanol extract was further analyzed using LC- MS analysis.

RESULTS

Methanol extract and its bioactive aqueous fraction exhibited significant and better in vitro antioxidant and antiproliferative activity as compared to chloroform extract. PCM treatment caused hepatotoxicity as assessed by altered levels of various hepatic biomarkers (increase in the levels of ALT, AST, ALP, albumin, triglycerides, cholesterol, TBARS, and AOPPs as well as decrease in GSH and TrxR levels) along with histopathological changes (portal to portal bridging, necrosis, and inflammation). Methanolic extract (200, 400 and 800 mg/kg) and its aqueous fraction treatment (25, 50 and 100 mg/kg) significantly restored elevated hepatic biomarkers, oxidative stress, and protected normal hepato-architecture. LC-MS analysis of aqueous fraction showed presence of rutin and kaempferol. In silico analysis further showed the capability of rutin to make complex with TNF-α and block its interaction with the target site.

CONCLUSION

Aqueous fraction showed maximum hepatoprotective potential as conceived through in vitro and in vivo studies. Presence of rutin may explain hepatoprotective potential of P. divaricata.

In-Cell Structural Biology by NMR: The Benefits of the Atomic Scale

In-cell structural biology aims at extracting structural information about proteins or nucleic acids in their native, cellular environment. This emerging field holds great promise and is already providing new facts and outlooks of interest at both fundamental and applied levels. NMR spectroscopy has important contributions on this stage: It brings information on a broad variety of nuclei at the atomic scale, which ensures its great versatility and uniqueness. Here, we detail the methods, the fundamental knowledge, and the applications in biomedical engineering related to in-cell structural biology by NMR. We finally propose a brief overview of the main other techniques in the field (EPR, smFRET, cryo-ET, etc.) to draw some advisable developments for in-cell NMR. In the era of large-scale screenings and deep learning, both accurate and qualitative experimental evidence are as essential as ever to understand the interior life of cells. In-cell structural biology by NMR spectroscopy can generate such a knowledge, and it does so at the atomic scale. This review is meant to deliver comprehensive but accessible information, with advanced technical details and reflections on the methods, the nature of the results, and the future of the field.

Salvage Therapy for Relapsed Malignant Pleural Mesothelioma: A Systematic Review and Network Meta-Analysis

Simple Summary

Malignant pleural mesothelioma (MPM) is an aggressive cancer with limited therapeutic options. Pemetrexed plus platinum is a standard first-line therapy, but options for second-line therapy in patients with relapsed mesothelioma remain controversial. Several drugs were recently introduced to treat relapsed MPM. We conducted a comprehensive systematic review and network meta-analysis to evaluate the efficacy of these drugs according to published randomized controlled trials. Nivolumab alone or nivolumab plus ipilimumab provided significantly longer overall survival (OS), and treatment with nivolumab plus ipilimumab was associated with the best OS based on the surface under the cumulative ranking curve (SUCRA). The network meta-analysis revealed that tremelimumab, vorinostat, chemotherapy (CTX), asparagine–glycine–arginine–human tumor necrosis factor plus CTX, nivolumab alone, and nivolumab plus ipilimumab all produced significant progression-free survival (PFS) benefits compared with placebo, with nivolumab plus ipilimumab ranked first for PFS according to SUCRA.

Abstract

Patients with malignant pleural mesothelioma (MPM) have very poor prognoses, and pemetrexed plus platinum is the standard first-line therapy. However, the second-line therapy for relapsed MPM remains controversial. A comprehensive search was performed to identify randomized controlled trials (RCTs) evaluating various second-line regimens in patients with relapsed MPM. Indirect comparisons of overall survival (OS) and progression-free survival (PFS) were performed using network meta-analysis. Surface under the cumulative ranking curve (SUCRA) values were used to rank the included treatments according to each outcome. Nivolumab alone or nivolumab plus ipilimumab provided significantly longer OS than placebo (hazard ratio (HR): 0.72, 95% confidence interval (CI): 0.55–0.94 for nivolumab alone; HR: 0.54, 95% CI: 0.31–0.92 for nivolumab plus ipilimumab). The best SUCRA ranking for OS was identified for nivolumab plus ipilimumab (SUCRA: 90.8%). Tremelimumab, vorinostat, nivolumab alone, chemotherapy (CTX), asparagine–glycine–arginine–human tumor necrosis factor plus CTX, and nivolumab plus ipilimumab all produced noticeable PFS benefits compared with placebo. Nivolumab plus ipilimumab had the best PFS ranking (SUCRA: 92.3%). Second-line treatment with nivolumab plus ipilimumab provided the OS and PFS outcomes for patients with relapsed MPM.

Peptide-Based Drug Delivery Systems

Peptide-based drug delivery systems have many advantages when compared to synthetic systems in that they have better biocompatibility, biochemical and biophysical properties, lack of toxicity, controlled molecular weight via solid phase synthesis and purification. Lysosomes, solid lipid nanoparticles, dendrimers, polymeric micelles can be applied by intravenous administration, however they are of artificial nature and thus may induce side effects and possess lack of ability to penetrate the blood-brain barrier. An analysis of nontoxic drug delivery systems and an establishment of prospective trends in the development of drug delivery systems was needed. This review paper summarizes data, mainly from the past 5 years, devoted to the use of peptide-based carriers for delivery of various toxic drugs, mostly anticancer or drugs with limiting bioavailability. Peptide-based drug delivery platforms are utilized as peptide–drug conjugates, injectable biodegradable particles and depots for delivering small molecule pharmaceutical substances (500 Da) and therapeutic proteins. Controlled drug delivery systems that can effectively deliver anticancer and peptide-based drugs leading to accelerated recovery without significant side effects are discussed. Moreover, cell penetrating peptides and their molecular mechanisms as targeting peptides, as well as stimuli responsive (enzyme-responsive and pH-responsive) peptides and peptide-based self-assembly scaffolds are also reviewed.

Ligand-modified homologous targeted cancer cell membrane biomimetic nanostructured lipid carriers for glioma therapy

The main treatment measure currently used for glioma treatment is chemotherapy; the biological barrier of solid tumors hinders the deep penetration of nanomedicines and limits anticancer therapy. Furthermore, the poor solubility of many chemotherapeutic drugs limits the efficacy of antitumor drugs. Therefore, improving the solubility of chemotherapeutic agents and drug delivery to tumor tissues through the blood-brain barrier (BBB) and blood-brain tumor barrier (BBTB) are major challenges in glioma treatment. Nanostructured lipid carriers (NLCs) have high drug loading capacity, high stability, and high in vivo safety; moreover, they can effectively improve the solubility of insoluble drugs. Therefore, in this study, we used solvent volatilization and ultrasonic melting methods to prepare dihydroartemisinin nanostructured lipid carrier (DHA-NLC). We further used the glioma C6 cancer cell (CC) membrane to encapsulate DHA-NLC owing to the homologous targeting mechanism of the CC membrane; however, the targeting ability of the CC membrane was weak. We accordingly used targeting ligands for modification, and developed a bionanostructured lipid carrier with BBB and BBTB penetration and tumor targeting abilities. The results showed that DHA-loaded NGR/CCNLC (asparagine-glycine-arginine, NGR) was highly targeted, could penetrate the BBB and BBTB, and showed good anti-tumor effects both in vitro and in vivo, which could effectively prolong the survival time of tumor-bearing mice. Thus, the use of DHA-loaded NGR/CCNLC is an effective strategy for glioma treatment and has the potential to treat glioma.

Peptide-drug conjugate-based novel molecular drug delivery system in cancer

Drug delivery systems are generally believed to comprise drugs and excipients. A peptide-drug conjugate is a single molecule that can simultaneously play multiple roles in a drug delivery system, such as in vivo drug distribution, targeted release, and bioactivity functions. This molecule can be regarded as an integrated drug delivery system, so it is called a molecular drug delivery system. In the context of cancer therapy, a peptide-drug conjugate comprises a tumor-targeting peptide, a payload, and a linker. Tumor-targeting peptides specifically identify membrane receptors on tumor cells, improve drug-targeted therapeutic effects, and reduce toxic and side effects. Payloads with bioactive functions connect to tumor-targeting peptides through linkers. In this review, we explored ongoing clinical work on peptide-drug conjugates targeting various receptors. We discuss the binding mechanisms of tumor-targeting peptides and related receptors, as well as the limiting factors for peptide-drug conjugate-based molecular drug delivery systems.

NGR-TNF Engineering with an N-Terminal Serine Reduces Degradation and Post-Translational Modifications and Improves Its Tumor-Targeting Activity

The therapeutic index of cytokines in cancer therapy can be increased by targeting strategies based on protein engineering with peptides containing the CNGRC (NGR) motif, a ligand that recognizes CD13-positive tumor vessels. We show here that the targeting domain of recombinant CNGRC-cytokine fusion proteins, such as NGR-TNF (a CNGRC-tumor necrosis factor-α (TNF) conjugate used in clinical studies) and NGR-EMAP-II, undergoes various post-translational modification and degradation reactions that lead to the formation of markedly heterogeneous products. These modifications include N-terminal cysteine acetylation or the formation of various asparagine degradation products, the latter owing to intramolecular interactions of the cysteine α-amino group with asparagine and/or its succinimide derivative. Blocking the cysteine α-amino group with a serine (SCNGRC) reduced both post-translational and degradation reactions. Furthermore, the serine residue reduced the asparagine deamidation rate to isoaspartate (another degradation product) and improved the affinity of NGR for CD13. Accordingly, genetic engineering of NGR-TNF with the N-terminal serine produced a more stable and homogeneous drug (called S-NGR-TNF) with improved antitumor activity in tumor-bearing mice, either when used alone or in combination with chemotherapy. In conclusion, the targeting domain of NGR-cytokine conjugates can undergo various untoward modification and degradation reactions, which can be markedly reduced by fusing a serine to the N-terminus. The SCNGRC peptide may represent a ligand for cytokine delivery to tumors more robust than conventional CNGRC. The S-NGR-TNF conjugate (more stable, homogeneous, and active than NGR-TNF) could be rapidly developed for clinical trials.