SS30, a novel thioaptamer targeting CD123, inhibits the growth of acute myeloid leukemia cells

Nucleic acid therapeutics as differentiation agents for myeloid leukemias

Differentiation therapy has proven to be a success story for patients with acute promyelocytic leukemia. However, the remaining subtypes of acute myeloid leukemia (AML) are treated with cytotoxic chemotherapies that have limited efficacy and a high likelihood of resistance. As differentiation arrest is a hallmark of AML, there is increased interest in developing differentiation-inducing agents to enhance disease-free survival. Here, we provide a comprehensive review of current reports and future avenues of nucleic acid therapeutics for AML, focusing on the use of targeted nucleic acid drugs to promote differentiation. Specifically, we compare and discuss the precision of small interfering RNA, small activating RNA, antisense oligonucleotides, and aptamers to modulate gene expression patterns that drive leukemic cell differentiation. We delve into preclinical and clinical studies that demonstrate the efficacy of nucleic acid-based differentiation therapies to induce leukemic cell maturation and reduce disease burden. By directly influencing the expression of key genes involved in myeloid maturation, nucleic acid therapeutics hold the potential to induce the differentiation of leukemic cells towards a more mature and less aggressive phenotype. Furthermore, we discuss the most critical challenges associated with developing nucleic acid therapeutics for myeloid malignancies. By introducing the progress in the field and identifying future opportunities, we aim to highlight the power of nucleic acid therapeutics in reshaping the landscape of myeloid leukemia treatment.

Binary Nanodrug-Delivery System Designed for Leukemia Therapy: Aptamer- and Transferrin-Codecorated Daunorubicin- and Luteolin-Coloaded Nanoparticles

Objective

This study aimed to develop a binary nanodrug-delivery system decorated with aptamers (APs) and transferrin (Tf) and loaded with daunorubicin (Drn) and luteolin (Lut) for the treatment of leukemia.

Methods

Oligonucleotide AP- and Tf-contaiing ligands were designed and synthesized separately. AP-decorated Drn-loaded nanoparticles (AP-Drn NPs) and Tf-Lut NPs were prepared by self-assembly. An AP- and Tf-codecorated Drn- and Lut-coloaded nanodrug-delivery system (AP/Tf-Drn/Lut NPs) was prepared by self-assembly of AP-Drn NPs and Tf-Lut NPs. In vitro and in vivo efficiency of the system was evaluated on leukemia cell line and cell-bearing mouse model in comparison with single ligand-decorated, single drug-loaded and free-drug formulations.

Results

AP/Tf-Drn/Lut NPs were spherical and nanosized (187.3±5.3 nm) and loaded with about 85% of drugs. In vitro cytotoxicity of AP/Tf-Drn/Lut NPs was remarkably higher than single ligand-decorated ones. Double drug-loaded AP/Tf-Drn/Lut NPs exhibited higher tumor-cell inhibition than single drug-loaded ones, which showed a synergic effect of the two drugs. AP/Tf-Drn/Lut NPs achieved the most efficient antileukemic activity and absence of toxicity in vivo.

Conclusion

The present study showed that AP/Tf-Drn/Lut NPs are a promising drug-delivery system for targeted treatment of leukemia, due to the synergic effect of the two drugs in this system. The limitations of this system include stability during large-scale production and application from bench to bedside.

The Research Advances of Aptamers in Hematologic Malignancies

Currently, research for hematological malignancies is very intensive, with many breakthroughs. Among them, aptamer-based targeted therapies could be counted. Aptamer is a targeting tool with many unique advantages (easy synthesis, low toxicity, easy modification, low immunogenicity, nano size, long stability, etc.), therefore many experts screened corresponding aptamers in various hematological malignancies for diagnosis and treatment. In this review, we try to summarize and provide the recent progress of aptamer research in the diagnosis and treatment of hematologic malignancies. Until now, 29 aptamer studies were reported in hematologic malignancies, of which 12 aptamers were tested in vivo and the remaining 17 aptamers were only tested in vitro. In this case, 11 aptamers were combined with chemotherapeutic drugs for the treatment of hematologic malignancies, 4 aptamers were used in combination with nanomaterials for the diagnosis and treatment of hematologic malignancies, and some studies used aptamers for the targeted transportation of siRNA and miRNA for targeted therapeutic effects. Their research provides multiple approaches to achieve more targeted goals. These findings show promising and encouraging future for both hematological malignancies basic and clinical trials research.

Aptamer grafted nanoparticle as targeted therapeutic tool for the treatment of breast cancer

Breast carcinomas repeat their number and grow exponentially making it extremely frequent malignancy among women. Approximately, 70-80% of early diagnosed or non-metastatic conditions are treatable while the metastatic cases are considered ineffective to treat with current ample amount of therapy. Target based anti-cancer treatment has been in the limelight for decades and is perceived significant consideration of scientists. Aptamers are the 'coming of age' therapeutic approach, selected using an appropriate tool from the library of sequences. Aptamers are non-immunogenic, stable, and high-affinity ligand which are poised to reach the clinical benchmark. With the heed in nanoparticle application, the delivery of aptamer to the specific site could be enhanced which also protects them from nuclease degradation. Moreover, nanoparticles due to robust structure, high drug entrapment, and modifiable release of cargo could serve as a successful candidate in the treatment of breast carcinoma. This review would showcase the method and modified method of selection of aptamers, aptamers that were able to make its way towards clinical trial and their targetability and selectivity towards breast cancers. The appropriate usage of aptamer-based biosensor in breast cancer diagnosis have also been discussed.

Novel nucleic acid aptamer gold (Au)-nanoparticles (AuNPs-AptHLA-G5-1 and AuNPs-AptHLA-G5-2) to detect the soluble human leukocyte antigen G5 subtype (HLA-G5) in liquid samples

Background

The human leukocyte antigen G5 subtype (HLA-G5) is a major histocompatibility complex (MHC) molecule that is selectively expressed at the maternal-foetal tissue interface and is required for the successful implantation of the in vitro fertilized embryo. It is critical to detect HLA-G5, especially HLA-G5 expression in embryo fluid, during in vitro embryo incubation and culture. However, the specificity and sensitivity of traditional ELISA methods to detect sHLA-G5 are insufficient. This work aimed to explore novel nucleic acid aptamer gold (Au)-nanoparticles to detect soluble HLA-G5 in liquid samples.

Methods

Soluble HLA-G5 was obtained using a prokaryotic expression system, and two novel aptamers (HLA-G5-Apt1 and HLA-G5-Apt2) detecting HLA-G5 were screened by the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method. Small (10 nm) gold nanoparticles (AuNPs) were incubated with AptHLAs to form two novel nucleic acid aptamers: Au-nanoparticles (AuNPs-AptHLA-G5-1 and AuNPs-AptHLA-G5-2).

Results

The results showed that AptHLA-G5-1 and AptHLA-G5-2 have a high affinity for HLA-G5 and can detect its presence in liquid samples. Using the colorimetric sensing method, AuNPs-AptHLA-G1 had a detection limit as low as 20 ng/mL (recovery range between 98.7% to 102.0%), while AuNPs-AptHLA-G2 had a detection limit as low as 20 ng/mL (recovery range between 98.9% to 103.6%).

Conclusions

Our work demonstrates that novel AuNPs are efficient detectors for HLA-G5 and are useful for diagnosis and treatment in the field of obstetrics-gynaecology.

CD123 thioaptamer protects against sepsis via the blockade between IL-3/CD123 in a cecal ligation and puncture rat model

Sepsis is one of the most common causes of death in ICU and especially is a harmful and a life-threatened disease to pediatrics in the world. It has been demonstrated that IL-3 plays an essential role in the processing of sepsis and the inhibition of IL-3 may alleviate sepsis progress. In our previous study, we selected a novel CD123 aptamer successfully which could inhibit the interaction of CD123 and IL-3. The aim of this study is to explore the protection ability of the first thioaptamer SS30 against sepsis in a cecal ligation and puncture (CLP) rat model. Serum IL-3 level of sepsis patients was assessed by ELISA. CLP rat model was applied in all experimental groups. CD123 thioaptamer SS30 and CD123 antibody were used to block the recognition between IL-3 and CD123. Body weight, temperature, blood gas, MAP, and serum cytokines of four grouped rats were assessed. Flow cytometry was utilized to evaluate JAK2 and STAT5 proteins. After the administration of SS30 or CD123 antibody, the rats in SS30 and CD123 antibody group had lower cytokines values(lactate, TNF-α, IL-1β, and IL-6), whereas exhibited higher value of core temperature, MAP, PO₂/FiO₂, and ETCO₂ than those in the CLP group. The expression level of phosphorylated JAK2 and STAT5 was declined and the survival rate of rats was increased. In addition, the protection ability of SS30 was better than CD123 antibody. Therefore, CD123 thioaptamer SS30 could reduce mortality by down-regulating the phosphorylated JAK2/STAT5 signaling pathway, and reduce serum cytokines which involving in sepsis development in CLP rat model.