Light induced drug release from a folic acid-drug conjugate

Design and validation of a low-cost photomodulator for in vivo photoactivation of a mGluR5 inhibitor

Purpose: Severe side effects prevent the utilization of otherwise promising drugs in treatments. These side effects arise when drugs affect untargeted tissues due to poor target specificity. In photopharmacology, light controls the timing and the location of drug delivery, improving treatment specificity and pharmacokinetic control. Photopharmaceuticals have not seen widespread adoption in part because researchers do not always have access to reliable and reproducible light delivery devices at prices which fit within the larger research budget. Method: In this work, we present a customizable photomodulator for use in both wearable and implantable devices. For experimental validation of the photomodulator, we photolyse JF-NP-26 in rats. Results: We successfully drive in vivo photopharmacology with a tethered photomodulator and demonstrate modifications which enable the photomodulator to operate wirelessly. Conclusion: By documenting our photomodulator development, we hope to introduce researchers to a simple solution which significantly lowers the engineering barriers to photopharmacology research.

Graphical abstract

Researchers present a photomodulator, a device designed to facilitate in vivo photopharmacology. They demonstrate the in vivo capabilities of the photomodulator by photoreleasing raseglurant, an mGluR5 inhibitor, to treat pain in an acute rat model and follow this study by showing how to reconfigure the photomodulator to work wirelessly and interface with other biomedical devices.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13534-023-00334-3.

Bioorthogonally Assisted Phototherapy: Recent Advances and Prospects

Photoresponsive materials offer excellent spatiotemporal control over biological processes and the emerging phototherapeutic methods are expected to have significant effects on targeted cancer therapies. Recent examples show that combination of photoactivatable approaches with bioorthogonal chemistry enhances the precision of targeted phototherapies and profound implications are foreseen particularly in the treatment of disperse/diffuse tumors. The extra level of on-target selectivity and improved spatial/temporal control considerably intensified related bioorthogonally assisted phototherapy research. The anticipated growth of further developments in the field justifies the timeliness of a brief summary of the state of the art.

Carborane-Containing Folic Acid bis-Amides: Synthesis and In Vitro Evaluation of Novel Promising Agents for Boron Delivery to Tumour Cells

The design of highly selective low-toxic, low-molecular weight agents for boron delivery to tumour cells is of decisive importance for the development of boron neutron capture therapy (BNCT), a modern efficient combined method for cancer treatment. In this work, we developed a simple method for the preparation of new closo- and nido-carborane-containing folic acid bis-amides containing 18-20 boron atoms per molecule. Folic acid derivatives containing nido-carborane residues were characterised by high water solubility, low cytotoxicity, and demonstrated a good ability to deliver boron to tumour cells in in vitro experiments (up to 7.0 µg B/10⁶ cells in the case of U87 MG human glioblastoma cells). The results obtained demonstrate the high potential of folic acid-nido-carborane conjugates as boron delivery agents to tumour cells for application in BNCT.

Advances in Functionalized Photosensitive Polymeric Nanocarriers

The synthesis of light-responsive nanocarriers (LRNs) with a variety of surface functional groups and/or ligands has been intensively explored for space-temporal controlled cargo release. LRNs have been designed on demand for photodynamic-, photothermal-, chemo-, and radiotherapy, protected delivery of bioactive molecules, such as smart drug delivery systems and for theranostic duties. LRNs trigger the release of cargo by a light stimulus. The idea of modifying LRNs with different moieties and ligands search for site-specific cargo delivery imparting stealth effects and/or eliciting specific cellular interactions to improve the nanosystems’ safety and efficacy. This work reviews photoresponsive polymeric nanocarriers and photo-stimulation mechanisms, surface chemistry to link ligands and characterization of the resultant nanosystems. It summarizes the interesting biomedical applications of functionalized photo-controlled nanocarriers, highlighting the current challenges and opportunities of such high-performance photo-triggered delivery systems.

Targeted Cancer Therapy Using Compounds Activated by Light

Cancer chemotherapy is affected by a modest selectivity and toxic side effects of pharmacological interventions. Among novel approaches to overcome this limitation and to bring to therapy more potent and selective agents is the use of light for selective activation of anticancer compounds. In this review, we focus on the anticancer applications of two light-activated approaches still in the experimental phase: photoremovable protecting groups ("photocages") and photoswitches. We describe the structural considerations behind the development of novel compounds and the plethora of assays used to confirm whether the photochemical and pharmacological properties are meeting the stringent criteria for an efficient in vivo light-dependent activation. Despite its immense potential, light activation brings many challenges, and the complexity of the task is very demanding. Currently, we are still deeply in the phase of pharmacological tools, but the vivid research and rapid development bring the light of hope for potential clinical use.

AminoBODIPY Conjugates for Targeted Drug Delivery Systems and Real-Time Monitoring of Drug Release

In this work, we report two concepts of drug delivery based on small-molecule drug conjugates with the ability of specific targeting and drug release monitoring via ratiometric fluorescence. The functionality of these concepts has been verified by two model systems consisting of three parts: (i) fluorescent aminoBODIPY for real-time detection of conjugate cleavage, (ii) a c(RGDfK) peptide specific for α_vβ₃ integrin receptors targeting angiogenesis in most solid tumors or redBODIPY for conjugate cleavage monitoring via FRET, and (iii) pegylated-2-phenyl-3-hydroxy-4(1H)-quinolinone (3HQ) as a model drug. The model drug release is based on a self-immolative disulfide linker sensitive to environments containing thiols, especially glutathione, which is overexpressed in cancer cells. The results show effective thiol-mediated cleavage of the fluorescent reporter and the subsequent liberation of the drug in a tube. The conjugate with c(RGDfK) was confirmed to penetrate the cells via interaction with integrin receptors. Drug release from this conjugate is possible to monitor inside the cells. Further, the synthetic approach to the conjugates and the method of fluorescence monitoring of the drug release have also been described.

pH-Responsive Self-Assemblies from the Designed Folic Acid-Modified Peptide Drug for Dual-Targeting Delivery

Targeting delivery is a promising technique for the therapy of cancers. A molecule FA-EEYSV-NH₂, which consists of target recognition site folic acid (FA), dipeptide linker, and peptide drug, was designed as a novel anticancer prodrug. The molecules could self-assemble into nanoparticles at pH 7.0 and nanofibers at pH 5.0. By the aid of pH-responsiveness, the self-assemblies were used purposefully as targeted vehicles of self-delivery prodrugs. The results of cell toxicity and internalization assays have proved that the self-assemblies have good cancer cell selectivity. The selection was mainly attributed to the pH-responsive structure transition of self-assemblies and the FA active-targeting effect. We hope that our work could provide a useful strategy for finely tuning the properties and activities of peptide-based supramolecular nanomaterials, thus optimizing nanomedicines with enhanced performance.

Photo-controlled delivery of a potent analogue of doxorubicin

Highly cytotoxic agents have found an important niche in targeted anticancer therapy. Here we develop a new light release strategy for the targeting of one of these agents, 2-pyrrolinodoxorubicin, showing dramatic enhancements in toxicity with light and single digit nM potency.

Advances in targeting the folate receptor in the treatment/imaging of cancers

The folate receptor (FR) is a recognised biomarker for tumour cells due to its overexpression on a large number of tumours. Consequently, the FR has been exploited by many diagnostic and therapeutic tools to allow targeted delivery to, and imaging of, cancer cells. Herein, we describe the many different approaches by which this has been achieved, including the attachment of folate to potent chemotherapeutic drugs to form FR-targeting small molecule-drug conjugates (SMDCs), FR-targeting antibodies (as antibody alone and as an antibody-drug conjugate), and in the form of complementary nanotechnology-folate platforms; as well as imaging variants thereof. The potential of exploiting the FR for targeted therapy/imaging has the potential to revolutionise the way several cancers are treated. These FR-targeted technologies can also pave the way for inspiring further sophisticated drug conjugates, especially as this receptor is being targeted by use of several complementary technologies: small molecule, nanoparticle and protein-based - thus providing broad and distinct knowledge in the area.

A sequential enzyme-activated and light-triggered pro-prodrug nanosystem for cancer detection and therapy

A sequential enzyme-activated and light-triggered pro-prodrug has been developed for cancer biomarker detection and on-demand therapy.