Specific Target Research Articles

How Natural Enzymes and Synthetic Ribozymes Generate Methylated Nucleotides in RNA.

Methylation of RNA nucleotides represents an important layer of gene expression regulation, and perturbation of the RNA methylome is associated with pathophysiology. In cells, RNA methylations are installed by RNA methyltransferases (RNMTs) that are specialized to catalyze particular types of methylation (ribose or different base positions). Furthermore, RNMTs must specifically recognize their appropriate target RNAs within the RNA-dense cellular environment. Some RNMTs are catalytically active alone and achieve target specificity via recognition of sequence motifs and/or RNA structures. Others function together with protein cofactors that can influence stability, S-adenosyl-L-methionine binding, and RNA affinity as well as aiding specific recruitment and catalytic activity. Association of RNMTs with guide RNAs represents an alternative mechanism to direct site-specific methylation by an RNMT that lacks intrinsic specificity. Recently, ribozyme-catalyzed methylation of RNA has been achieved in vitro, and here, we compare these different strategies for RNA methylation from structural and mechanistic perspectives.

Synthesis and in-silico Studies of 4-phenyl thiazol-2-amine Derivatives as Putative Anti-breast Cancer Agents.

Breast cancer (BC) is the second-leading cause of cancer-related fatalities in women after lung cancer worldwide. The development of BC is significantly influenced by estrogen receptors (ERs). The problem with current cancer treatments is selectivity, target specificity, cytotoxicity, and developing resistance. Thiazole scaffolds are gaining popularity in drug discovery due to their broad range of biological activity. It has the extraordinary capacity to control a variety of cellular pathways, and its potential for selective anticancer activity can be explored. Synthesis and in-silico</i> studies of 4-Phenyl thiazol-2-amine derivatives as anti-breast cancer agents and molecular docking was used to assess the compounds' capacity to bind ER-α protein target. In this study, 4-Phenylthiazol-2-amine derivatives (3a-j) have been synthesized, and using Schrodinger software, molecular docking and ADME studies of the compounds were conducted. Most of the synthesized compounds have shown dock scores ranging from -6.658 to - 8.911 kcal/mol, which is better than the standard drug tamoxifen (-6.821 kcal/mol). According to molecular docking, all compounds fit in the protein's active site and have the same hydrophobic pocket as the standard drug tamoxifen. Further, all of the compounds' ADME properties are below acceptable limits. Compound 3e showed the best docking score of -8.911. All compounds' ADME properties are within acceptable limits, and their p/o coefficients fall within a range, suggesting they will all have sufficient absorption at the site of action. These compounds can be evaluated invitro</i> and in-vivo</i> in the future.

Risk of early hepatocellular carcinoma recurrence following liver resection: arbitrary specification or possible target to improve outcome?

Risk of early hepatocellular carcinoma recurrence following liver resection: arbitrary specification or possible target to improve outcome?

In silico analysis of Naringenin and its O-alkyl derivatives for its potential binding with Estrogen Receptor- α

Breast cancer remains the second-most significant cause of female mortality worldwide. The emergence of naturally occurring plant-derived compounds called phytoestrogens has aroused substantial interest in their potential to mitigate breast cancer. Phytoestrogens demonstrate structural similarities to human estrogen and can therefore interact with the estrogen receptors. Naringenin, an important flavonoid and phytoestrogen, has gathered significant attention in the field of cancer due to its potential anti-inflammatory and antioxidant properties while its O-alkyl derivatives can enhance its bioavailability and target specificity. In this study, we have screened Naringenin and four of its O-alkyl derivatives, namely Isosakuranetin, 5-O-Methylnaringenin, Sakuranetin and 4',7-Di-O-methylnaringenin for their binding affinity with estrogen receptor-α (PDB ID: 6VJD). Molecular docking studies targeting estrogen receptor-α (PDB ID: 6VJD) revealed favorable binding energies and interaction patterns for naringenin and its derivatives, suggesting potential as therapeutic agents against breast cancer. Additionally, analysis with SwissADME highlighted the compounds' permeability across the blood-brain barrier (BBB), high absorption rates and water solubility, emphasizing their potential for therapeutic applications beyond breast cancer. Furthermore, the compounds exhibited promising pharmacokinetic profiles, synthetic accessibility and adherence to Lipinski's rule of five, supporting their candidacy for further development as therapeutic agents.

Advances in Light-Responsive Smart Multifunctional Nanofibers: Implications for Targeted Drug Delivery and Cancer Therapy.

Over the last decade, scientists have shifted their focus to the development of smart carriers for the delivery of chemotherapeutics in order to overcome the problems associated with traditional chemotherapy, such as poor aqueous solubility and bioavailability, low selectivity and targeting specificity, off-target drug side effects, and damage to surrounding healthy tissues. Nanofiber-based drug delivery systems have recently emerged as a promising drug delivery system in cancer therapy owing to their unique structural and functional properties, including tunable interconnected porosity, a high surface-to-volume ratio associated with high entrapment efficiency and drug loading capacity, and high mass transport properties, which allow for controlled and targeted drug delivery. In addition, they are biocompatible, biodegradable, and capable of surface functionalization, allowing for target-specific delivery and drug release. One of the most common fiber production methods is electrospinning, even though the relatively two-dimensional (2D) tightly packed fiber structures and low production rates have limited its performance. Forcespinning is an alternative spinning technology that generates high-throughput, continuous polymeric nanofibers with 3D structures. Unlike electrospinning, forcespinning generates fibers by centrifugal forces rather than electrostatic forces, resulting in significantly higher fiber production. The functionalization of nanocarriers on nanofibers can result in smart nanofibers with anticancer capabilities that can be activated by external stimuli, such as light. This review addresses current trends and potential applications of light-responsive and dual-stimuli-responsive electro- and forcespun smart nanofibers in cancer therapy, with a particular emphasis on functionalizing nanofiber surfaces and developing nano-in-nanofiber emerging delivery systems for dual-controlled drug release and high-precision tumor targeting. In addition, the progress and prospective diagnostic and therapeutic applications of light-responsive and dual-stimuli-responsive smart nanofibers are discussed in the context of combination cancer therapy.

Potential Targeting Mechanisms for Bone-Directed Therapies.

Bone development is characterized by complex regulation mechanisms, including signal transduction and transcription factor-related pathways, glycobiological processes, cellular interactions, transportation mechanisms, and, importantly, chemical formation resulting from hydroxyapatite. Any abnormal regulation in the bone development processes causes skeletal system-related problems. To some extent, the avascularity of cartilage and bone makes drug delivery more challenging than that of soft tissues. Recent studies have implemented many novel bone-targeting approaches to overcome drawbacks. However, none of these strategies fully corrects skeletal dysfunction, particularly in growth plate-related ones. Although direct recombinant enzymes (e.g., Vimizim for Morquio, Cerezyme for Gaucher, Elaprase for Hunter, Mepsevii for Sly diseases) or hormone infusions (estrogen for osteoporosis and osteoarthritis), traditional gene delivery (e.g., direct infusion of viral or non-viral vectors with no modifications on capsid, envelope, or nanoparticles), and cell therapy strategies (healthy bone marrow or hematopoietic stem cell transplantation) partially improve bone lesions, novel delivery methods must be addressed regarding target specificity, less immunogenicity, and duration in circulation. In addition to improvements in bone delivery, potential regulation of bone development mechanisms involving receptor-regulated pathways has also been utilized. Targeted drug delivery using organic and inorganic compounds is a promising approach in mostly preclinical settings and future clinical translation. This review comprehensively summarizes the current bone-targeting strategies based on bone structure and remodeling concepts while emphasizing potential approaches for future bone-targeting systems.

Ubiquitin-derived artificial binding proteins targeting oncofetal fibronectin reveal scaffold plasticity by β-strand slippage

Affilin proteins, artificial binding proteins based on the ubiquitin scaffold, have been generated by directed protein evolution to yield de-novo variants that bind the extra-domain B (EDB) of oncofetal fibronectin, an established marker of tumor neovasculature. The crystal structures of two EDB-specific Affilin variants reveal a striking structural plasticity of the ubiquitin scaffold, characterised by β-strand slippage, leading to different negative register shifts of the β5 strands. This process recruits amino acid residues from β5 towards the N-terminus to an adjacent loop region and subsequent residues into β5, respectively, remodeling the binding interface and leading to target specificity and affinity. Protein backbone alterations resulting from β-strand register shifts, as seen in the ubiquitin fold, can pose additional challenges to protein engineering as structural evidence of these events is still limited and they are difficult to predict. However, they can surface under the selection pressure of directed evolution and suggest that backbone plasticity allowing β-strand slippages can increase structural diversity, enhancing the evolutionary potential of a protein scaffold.

Identification of monoclonal antibodies from naive antibody phage-display libraries for protein detection in formalin-fixed paraffin-embedded tissues

Most antibodies used in immunohistochemistry (IHC) have been developed by animal immunization. We wanted to explore naive antibody repertoires displayed on filamentous phages as a source of full-length antibodies for IHC on Formalin-Fixed and Paraffin-Embedded (FFPE) tissues. We used two isogenic mouse fibroblast cell lines that express or not human HER2 to generate positive and negative FFPE pseudo-tissue respectively. Using these pseudo-tissues and previously described approaches based on differential panning, we isolated very efficient antibody clones, but not against HER2. To optimize HER2 targeting and tissue specificity, we first performed 3–4 rounds of in vitro panning using recombinant HER2 extracellular domain (ECD) to enrich the phage library in HER2 binders, followed by one panning round using the two FFPE pseudo-tissues to retain binders for IHC conditions. We then analyzed the bound phages using next-generation sequencing to identify antibody sequences specifically associated with the HER2-positive pseudo-tissue. Using this approach, the top-ranked clone identified by sequencing was specific to the HER2-positive pseudo-tissue and showed a staining pattern similar to that of the antibody used for the clinical diagnosis of HER2-positive breast cancer. However, we could not optimize staining on other tissues, showing that specificity was restricted to the tissue used for selection and screening. Therefore, future optimized protocols must consider tissue diversity early during the selection by panning using a wide collection of tissue types.

Aptamer-controlled gold nanozyme sensor for fluorescent and colorimetric dual-channel detection of methamphetamine

Methamphetamine (METH) is the second abused drug which affects abusers’ health and induces social crimes, developing novel methods with high sensitivity and selectivity for METH detecting is still challenging. In this paper, a colorimetric and fluorescent dual-channel sensor for METH has been constructed. We combine the enzyme-mimic catalytic activity of gold nanoparticles (GNPs) with high target specificity of METH aptamer to create a nanosensor (Apt-GNP), in the presence of METH, the absorption of 3,3′,5,5′-tetramethylbenzidine (OxTMB) at 650 nm enhanced with METH concentration increasing, while the absorption characteristic peak of GNPs at 530 nm remained almost unchanged. The ratio of A650nm/A530nm and METH concentration had a good linear relationship when METH concentration was in the range of 5–50 μM, and the corresponding linear equation is A650nm/A530nm = 0.00727CMETH (μM) + 0.783 with R2 = 0.997 and LOD = 0.40 μM (LOD = 3σ/s, n = 11). Interestingly, the fluorescence emission of Rhodamine B (RB) overlaps with the absorption spectrum of OxTMB which represents the content of METH and the fluorescence signal of RB can be quenched through internal filtering effect (IEF). Hence, when RB was doped to the detection system, the decay of RB fluorescence can reflect the concentrations change of METH. Accordingly, the linear equation is F/FR = –0.00751CMETH (μM) + 0.895 with R2 = 0.993 and LOD = 0.40 μM, where F was the fluorescence of the analytical solution at 580 nm with METH and FR was fluorescence of RB control solution. The dual-channel sensor can measure METH in serum and artificial urine successfully which is potential to be applied in drug-using crime sites and provide direct evidence to law enforcement officials.

Targeted reprogramming of tumor-associated macrophages for overcoming glioblastoma resistance to chemotherapy and immunotherapy

The resistance of glioblastoma multiforme (GBM) to standard chemotherapy is primarily attributed to the existence of tumor-associated macrophages (TAMs) in the GBM microenvironment, particularly the anti-inflammatory M2 phenotype. Targeted modulation of M2-TAMs is emerging as a promising strategy to enhance chemotherapeutic efficacy. However, combination TAM-targeted therapy with chemotherapy faces substantial challenges, notably in terms of delivery efficiency and targeting specificity. In this study, we designed a pH-responsive hierarchical brain-targeting micelleplex loaded with temozolomide (TMZ) and resiquimod (R848) for combination chemo-immunotherapy against GBM. This delivery system, termed PCPA&PPM@TR, features a primary Angiopep-2 decoration on the outer layer via a pH-cleavable linker and a secondary mannose analogue (MAN) on the middle layer. This pH-responsive hierarchical targeting strategy enables effective BBB permeability while simultaneous GBM- and TAMs-targeting delivery. GBM-targeted delivery of TMZ induces alkylation and triggers an anti-GBM immune response. Concurrently, TAM-targeted delivery of R848 reprograms their phenotype from M2 to pro-inflammatory M1, thereby diminishing GBM resistance to TMZ and amplifying the immune response. In vivo studies demonstrated that targeted modulation of TAMs using PCPA&PPM@TR significantly enhanced anti-GBM efficacy. In summary, this study proposes a promising brain-targeting delivery system for the targeted modulation of TAMs to combat GBM.

A peptide-salinomycin conjugate with a bystander effect reduces the stemness characteristics of ovarian cancer cells and enhances drug sensitivity

Salinomycin (Sal) has attracted considerable attention in the field of tumor treatment, especially for its inhibitory effect on cancer stem cells (CSCs) and drug-resistant tumor cells. However, its solubility and targeting specificity pose significant challenges to its pharmaceutical development. Sal-A6, a novel peptide-drug conjugate (PDC), was formed by linking the peptide A6 targeting the CSC marker CD44 with Sal using a specific linker. This conjugation markedly enhances the physicochemical properties of Sal and compared to Sal, Sal-A6 demonstrated a significantly increased activity against ovarian cancer. Furthermore, Sal-A6, employing a disulfide bond as a linker, exhibited bystander killing effect. Moreover, it induces substantial cytotoxic effect on both cancer stem cells and drug-resistant cells in addition to enhance chemosensitivity of resistant ovarian cancer cells. In summary, the results indicated that Sal-A6, a novel PDC derived from Sal, has potential therapeutic applications in the treatment of ovarian cancer and drug-resistant patients. Additionally, this discovery offers insights for developing PDC-type drugs using Sal as a foundation.

Multifaceted Roles of Nerve Growth Factor: A Comprehensive Review with a Special Insight into Pediatric Perspectives.

Nerve growth factor (NGF) is a neurotrophic peptide largely revealed for its ability to regulate the growth and survival of peripheral sensory, sympathetic, and central cholinergic neurons. The pro-survival and regenerative properties of neurotrophic factors propose a therapeutic potential in a wide range of brain diseases, and NGF, in particular, has appeared as an encouraging potential treatment. In this review, a summary of clinical studies regarding NGF and its therapeutic effects published to date, with a specific interest in the pediatric context, will be attempted. NGF has been studied in neurological disorders such as hypoxic-ischemic encephalopathy, traumatic brain injury, neurobehavioral and neurodevelopmental diseases, congenital malformations, cerebral infections, and in oncological and ocular diseases. The potential of NGF to support neuronal survival, repair, and plasticity in these contexts is highlighted. Emerging therapeutic strategies for NGF delivery, including intranasal administration as well as advanced nanotechnology-based methods, are discussed. These techniques aim to enhance NGF bioavailability and target specificity, optimizing therapeutic outcomes while minimizing systemic side effects. By synthesizing current research, this review underscores the promise and challenges of NGF-based therapies in pediatric neurology, advocating for continued innovation in delivery methods to fully harness NGF's therapeutic potential.

Selective Activation of Cascade Assembly Amplification for DNA Methyltransferase Detection Using a Double-Loop Interlocked DNA Circuit.

Precise and reliable monitoring of DNA adenine methyltransferase (Dam) activity is essential for disease diagnosis and biological analysis. However, existing techniques for detecting Dam activity often rely on specific DNA recognition probes that are susceptible to DNA degradation and exhibit limited target sensitivity and specificity. In this study, we designed and engineered a stable and dynamic DNA nanodevice called the double-loop interlocked DNA circuit (DOOR) that enables the sensitive and selective monitoring of Dam activity in complex biological environments. The DOOR incorporates two interlocked specialized sequences: a palindromic sequence for Dam identification and an initiator sequence for signal amplification. In the presence of Dam, the DOOR is cleaved by double-stranded DNA phosphodiesterase I endonuclease, generating massive double-stranded DNA (dsDNA) units. These units can self-assemble into a long dsDNA scaffold, thereby enhancing the subsequent reaction kinetics. The dsDNA scaffold further triggers a hyperbranched hybrid chain reaction to produce a fluorescent 3D DNA nanonet, enabling more precise monitoring of the Dam activity. The DOOR device exhibits excellent sensitivity, specificity, and stability, rendering it a powerful tool for studying DNA methylation in various biological processes and diseases.

Generation of non-genetically modified, CAR-like, NK cells

BackgroundNatural killer (NK) cell therapy is considered an attractive and safe strategy for anticancer therapy. Nevertheless, when autologous or allogenic NK cells are used alone, the clinical benefit has been...

A High-Throughput Screening Strategy for Synthesizing Molecularly Imprinted Polymer Nanoparticles Selectively Targeting Tumors.

Molecularly imprinted polymers (MIPs) show significant promise as effective alternatives to antibodies in disease diagnosis and therapy. However, the challenging process of screening extensive libraries of monomer combinations and synthesis conditions to identify formulations with enhanced selectivity and affinity presents a notable time constraint. The need for expedient methods becomes clear in accelerating the strategic development of MIPs tailored for precise molecular recognition purposes. In this study, an innovative high-throughput screening methodology designed to identify the optimal MIP formulation for targeting tumors is presented. Employing a microtiter plate format, over 100 polymer syntheses are conducted, incorporating diverse combinations of functional monomers. Evaluation of binding performance utilizes fluorescence-based assays, focusing on an epitope of the epidermal growth factor receptor (EGFR). Through this meticulously structured screening process, synthesis conditions that produced MIP nanoparticles exhibiting substantial specificity for EGFR targeting (KD = 10-12m) are identified. These "bionic antibodies" demonstrate selective recognition of cancer cells in whole blood samples, even at concentrations as low as 5cellsmL-1. Further validation through fluorescent imaging confirms the tumor-specific localization of the MIPs in vivo. This highly efficient screening approach facilitates the strategic synthesis of imprinted polymers functioning as precision bioprobes.

Identification and Design of Novel Potential Antimicrobial Peptides Targeting Mycobacterial Protein Kinase PknB

Antimicrobial peptides have gradually gained advantages over small molecule inhibitors for their multifunctional effects, synthesising accessibility and target specificity. The current study aims to determine an antimicrobial peptide to inhibit PknB, a serine/threonine protein kinase (STPK), by binding efficiently at the helically oriented hinge region. A library of 5626 antimicrobial peptides from publicly available repositories has been prepared and categorised based on the length. Molecular docking using ADCP helped to find the multiple conformations of the subjected peptides. For each peptide served as input the tool outputs 100 poses of the subjected peptide. To maintain an efficient binding for relatively a longer duration, only those peptides were chosen which were seen to bind constantly to the active site of the receptor protein over all the poses observed. Each peptide had different number of constituent amino acid residues; the peptides were classified based on the length into five groups. In each group the peptide length incremented upto four residues from the initial length form. Five peptides were selected for Molecular Dynamic simulation in Gromacs based on higher binding affinity. Post-dynamic analysis and the frame comparison inferred that neither the shorter nor the longer peptide but an intermediate length of 15 mer peptide bound well to the receptor. Residual substitution to the selected peptides was performed to enhance the targeted interaction. The new complexes considered were further analysed using the Elastic Network Model (ENM) for the functional site’s intrinsic dynamic movement to estimate the new peptide’s role. The study sheds light on prospects that besides the length of peptides, the combination of constituent residues equally plays a pivotal role in peptide-based inhibitor generation. The study envisages the challenges of fine-tuned peptide recovery and the scope of Machine Learning (ML) and Deep Learning (DL) algorithm development. As the study was primarily meant for generation of therapeutics for Tuberculosis (TB), the peptide proposed by this study demands meticulous invitro analysis prior to clinical applications.Graphical

A New Multiplex TaqMan qPCR for Precise Detection and Quantification of Clavibacter michiganensis in Seeds and Plant Tissue.

Bacterial canker of tomato caused by Clavibacter michiganensis (Cm) is one of the most devastating bacterial diseases affecting the tomato industry worldwide. As the result of Cm colonization of the xylem, the susceptible host shows typical symptoms of wilt, marginal leaf necrosis, stem cankers, and ultimately plant death. However, what makes Cm an even more dangerous pathogen is its ability to infect seeds and plants without causing symptoms. Unfortunately, there are no resistant cultivars or effective chemical or biological control methods available to growers against Cm. Its control relies heavily on prevention. The implementation of a rapid and accurate detection tool is imperative to monitor the presence of Cm and prevent its spread. In this study, we developed a specific and sensitive multiplex TaqMan qPCR assay to detect Cm and distinguish it from related bacterial species that affect tomato plants. Two Cm chromosomal virulence-related genes, rhuM and tomA, were used as specific targets. The plant internal control tubulin alpha-3 was included in each of the multiplexes to improve the reliability of the assay. Specificity was evaluated with 37 bacterial strains including other Clavibacter spp. and related and unrelated bacterial pathogens from different geographic locations affecting a wide variety of hosts. Results showed that the assay is able to discriminate Cm strains from other related bacteria. The assay was validated on tissue and seed samples following artificial infection, and all tested samples accurately detected the presence of Cm. The tool described here is highly specific, sensitive, and reliable for the detection of Cm and allows the quantification of Cm in seeds, roots, stems, and leaves. The diagnostic assay can also be adapted for multiple purposes such as seed certification programs, surveillance, biosafety, the effectiveness of control methods, border protection, and epidemiological studies.[Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.

Actinium chelation and crystallization in a macromolecular scaffold

Targeted alpha therapy (TAT) pairs the specificity of antigen targeting with the lethality of alpha particles to eradicate cancerous cells. Actinium-225 [225Ac; t1/2 = 9.920(3) days] is an alpha-emitting radioisotope driving the next generation of TAT radiopharmaceuticals. Despite promising clinical results, a fundamental understanding of Ac coordination chemistry lags behind the rest of the Periodic Table due to its limited availability, lack of stable isotopes, and inadequate systems poised to probe the chemical behavior of this radionuclide. In this work, we demonstrate a platform that combines an 8-coordinate synthetic ligand and a mammalian protein to characterize the solution and solid-state behavior of the longest-lived Ac isotope, 227Ac [t1/2 = 21.772(3) years]. We expect these results to direct renewed efforts for 225Ac-TAT development, aid in understanding Ac coordination behavior relative to other +3 lanthanides and actinides, and more broadly inform this element’s position on the Periodic Table.

Rational Design of Targeted Gold Nanoclusters with High Affinity to Integrin αvβ3 for Combination Cancer Therapy.

The unique attributes of targeted nano-drug delivery systems (TNDDSs) over conventional cancer therapies in suppressing off-target effects make them one of the most promising options for cancer treatment. There is evidence that the density of surface-conjugated ligands is a crucial factor in achieving the desired therapeutic efficacy of TNDDSs, but this is hardly manageable in conventional nanomaterials. In this context, ligand-protected gold nanoclusters (AuNCs) are excellent candidates for developing new TNDDSs with a unique control on their surface functionalities, thus helping to achieve enhanced delivery performance. Here, we study the interactions and binding free energies between ten different functionalized Au144(SR)60 (SR = thiolate ligand) nanoclusters and integrin αvβ3 using molecular dynamics simulations and the umbrella sampling method to obtain the optimal formulations. The AuNCs were functionalized with anticancer drugs (5-fluorouracil or signaling pathways inhibitors, such as capivasertib, linifanib, tanespimycin, and taselisib) and integrin-targeting peptides (RGD4C or QS13), and we identified the optimal mixed ligand layer to enhance their binding affinity to the cancer cell receptor. The results showed that changing the proportions of the same type of ligands on the surface of AuNCs led to differences of up to 38 kcal/mol in computed binding free energies. RGD4C as the targeting peptide resulted in greater affinity for αvβ3, and in most formulations studied, a higher amount of drug than peptide was needed. Polar and charged residues, such as Ser123, Asp150, Tyr178, Arg214, and Asp251 were found to play a significant role in AuNC binding. Our simulations also revealed that Mn2+ cations are crucial for stabilizing the αvβ3-AuNC complex. These findings demonstrate the potential of carefully designing the surface composition of TNDDSs to optimize their target affinity and specificity.

Development of a RNA-protein complex based smart drug delivery system for 9-hydroxycamptothecin

Camptothecin (CPT) is a monoterpenoid indole alkaloid with a wide spectrum of anticancer activity. However, its application is hindered by poor solubility, lack of targeting specificity, and severe side effects. Structural derivatization of CPT and the development of suitable drug delivery systems are potential strategies for addressing these issues. In this study, we discovered that the protein Cytochrome P450 Family 1 Subfamily A Member 1 (CYP1A1) from Homo sapiens catalyzes CPT to yield 9-hydroxycamptothecin (9-HCPT), which exhibits increased water solubility and cytotoxicity. We then created a RNA-protein complex based drug delivery system with enzyme and pH responsiveness and improved the targeting and stability of the nanomedicine through protein module assembly. The subcellular localization of nanoparticles can be visualized using fluorescent RNA probes. Our results not only identified the protein CYP1A1 responsible for the structural derivatization of CPT to synthesize 9-HCPT but also offered potential strategies for enhancing the utilization of silk-based drug delivery systems in tumor therapy.