Precise Targeting Therapy of Orthotopic Gastric Carcinoma by siRNA and Chemotherapeutic Drug Codelivered in pH-Sensitive Nano Platform

Nanoparticles for Augmenting Therapeutic Potential and Alleviating the Effect of Di(2-ethylhexyl) Phthalate on Gastric Cancer

Changes in diet culture and modern lifestyle contributed to a higher incidence of gastrointestinal-related diseases, including gastritis, implicated in the pathogenesis of gastric cancer. This observation raised concerns regarding exposure to di(2-ethylhexyl) phthalate (DEHP), which is linked to adverse health effects, including reproductive and developmental problems, inflammatory response, and invasive adenocarcinoma. Research on the direct link between DEHP and gastric cancer is ongoing, and further studies are required to establish a conclusive association. In our study, extremely low concentrations of DEHP exerted significant effects on cell migration by promoting the epithelial-mesenchymal transition in gastric cancer cells. This effect was mediated by the modulation of the PI3K/AKT/mTOR and Smad2 signaling pathways. To address the DEHP challenges, our initial design of TPGS-conjugated fucoidan, delivered via pH-responsive nanoparticles, successfully demonstrated binding to the P-selectin protein. This achievement has not only enhanced the antigastric tumor efficacy but has also led to a significant reduction in the expression of malignant proteins associated with the condition. These findings underscore the promising clinical therapeutic potential of our approach.

Advances and Challenges of Stimuli-Responsive Nucleic Acids Delivery System in Gene Therapy

Gene therapy has emerged as a powerful tool to treat various diseases, such as cardiovascular diseases, neurological diseases, ocular diseases and cancer diseases. In 2018, the FDA approved Patisiran (the siRNA therapeutic) for treating amyloidosis. Compared with traditional drugs, gene therapy can directly correct the disease-related genes at the genetic level, which guarantees a sustained effect. However, nucleic acids are unstable in circulation and have short half-lives. They cannot pass through biological membranes due to their high molecular weight and massive negative charges. To facilitate the delivery of nucleic acids, it is crucial to develop a suitable delivery strategy. The rapid development of delivery systems has brought light to the gene delivery field, which can overcome multiple extracellular and intracellular barriers that prevent the efficient delivery of nucleic acids. Moreover, the emergence of stimuli-responsive delivery systems has made it possible to control the release of nucleic acids in an intelligent manner and to precisely guide the therapeutic nucleic acids to the target site. Considering the unique properties of stimuli-responsive delivery systems, various stimuli-responsive nanocarriers have been developed. For example, taking advantage of the physiological variations of a tumor (pH, redox and enzymes), various biostimuli- or endogenous stimuli-responsive delivery systems have been fabricated to control the gene delivery processes in an intelligent manner. In addition, other external stimuli, such as light, magnetic fields and ultrasound, have also been employed to construct stimuli-responsive nanocarriers. Nevertheless, most stimuli-responsive delivery systems are in the preclinical stage, and some critical issues remain to be solved for advancing the clinical translation of these nanocarriers, such as the unsatisfactory transfection efficiency, safety issues, complexity of manufacturing and off-target effects. The purpose of this review is to elaborate the principles of stimuli-responsive nanocarriers and to emphasize the most influential advances of stimuli-responsive gene delivery systems. Current challenges of their clinical translation and corresponding solutions will also be highlighted, which will accelerate the translation of stimuli-responsive nanocarriers and advance the development of gene therapy.

Recent advances in targeted gene silencing and cancer therapy by nanoparticle-based delivery systems

Nanomedicine has emerged as a promising platform for disease treatment and much progress has been achieved in the clinical translation for cancer treatment. Several types of nanomedicines have been approved for therapeutic application. However, many nanoparticles still suffer from challenges in the translation from bench to bedside. Currently, nanoparticle-based delivery systems have been developed to explore their functions in targeted gene silencing and cancer therapy. This review describes the research progress of different nano-carriers in targeted gene editing, and the recent progress in co-delivery of anticancer drugs and small ribonucleic acid. We also summarize the strategies for improving the specificity of carrier systems. Finally, we discuss the functions of targeted nano-carriers in overcoming chemotherapeutic drug resistance in cancer therapy. As research continues to advance, a better understanding of the safety including long-term toxicity, immunogenicity, and body metabolism may impel nanoparticle translation.

Classification of stomach adenocarcinoma based on fatty acid metabolism-related genes frofiling

Background: Fatty acid metabolism (FAM)-related genes play a key role in the development of stomach adenocarcinoma (STAD). Although immunotherapy has led to a paradigm shift in STAD treatment, the overall response rate of immunotherapy for STAD is low due to heterogeneity of the tumor immune microenvironment (TIME). How FAM-related genes affect TIME in STAD remains unclear.

Methods: The univariate Cox regression analysis was performed to screen prognostic FAM-related genes using transcriptomic profiles of the Cancer Genome Atlas (TCGA)-STAD cohort. Next, the consensus clustering analysis was performed to divide the STAD cohort into two groups based on the 13 identified prognostic genes. Then, gene set enrichment analysis (GSEA) was carried out to identify enriched pathways in the two groups. Furthermore, we developed a prognostic signature model based on 7 selected prognostic genes, which was validated to be capable in predicting the overall survival (OS) of STAD patients using the univariate Cox regression, least absolute shrinkage and selection operator (LASSO) regression, and multivariate Cox regression analyses. Finally, the “Estimation of STromal and Immune cells in MAlignant Tumours using Expression data” (ESTIMATE) algorithm was used to evaluate the stromal, immune, and ESTIMATE scores, and tumor purity of each STAD sample.

Results: A total of 13 FAM-related genes were identified to be significantly associated with OS in STAD patients. Two molecular subtypes, which we named Group 1 and Group 2, were identified based on these FAM-related prognostic genes using the consensus clustering analysis. We showed that Group 2 was significantly correlated with poor prognosis and displayed higher programmed cell death ligand 1 (PD-L1) expressions and distinct immune cell infiltration patterns. Furthermore, using GSEA, we showed that apoptosis and HCM signaling pathways were significantly enriched in Group 2. We constructed a prognostic signature model using 7 selected FAM-related prognostic genes, which was proven to be effective for prediction of STAD (HR = 1.717, 95% CI = 1.105–1.240, p < 0.001). After classifying the patients into the high- and low-risk groups based on our model, we found that patients in the high-risk group tend to have more advanced T stages and higher tumor grades, as well as higher immune scores. We also found that the risk scores were positively correlated with the infiltration of certain immune cells, including resting dendritic cells (DCs), and M2 macrophages. We also demonstrated that elevated expression of gamma-glutamyltransferase 5 (GGT5) is significantly associated with worse OS and disease-free survival (DFS), more advanced T stage and higher tumor grade, and increased immune cell infiltration, suggesting that STAD patients with high GGT5 expression in the tumor tissues might have a better response to immunotherapy.

Conclusion: FAM-related genes play critical roles in STAD prognosis by shaping the TIME. These genes can regulate the infiltration of various immune cells and thus are potential therapeutic targets worthy of further investigation. Furthermore, GGT5 was a promising marker for predicting immunotherapeutic response in STAD patients.

Synergistic Silencing of Skp2 by siRNA Self-Assembled Nanoparticles as a Therapeutic Strategy for Advanced Prostate Cancer

Advanced prostate cancer, harboring multiple mutations of tumor suppressor genes, is refractory to conventional therapies. Knockout of the Skp2 gene blocks pRb/p53 doubly deficient prostate cancer in mice, which inspired the authors to develop an approach for delivering siRNA that would efficiently silence Skp2 (siSkp2) in vivo. Here, a facile strategy is reported to directly assemble siSkp2 with the natural compound quercetin (Que) into supramolecular nanoparticles (NPs). This carrier-free siSkp2 delivery system could effectively protect siSkp2 from degradation in serum and enhance its cellular internalization. Furthermore, the siSkp2/Que NPs exhibit synergistic effects in Skp2 silencing, because they can degrade the mRNA and protein of Skp2 simultaneously. Indeed, siSkp2/Que NPs remarkably diminish the Skp2 abundance and further inhibit the proliferation and migration of TMU cells (RB1/TP53/KRAS triple mutations) in vitro. The in vivo results further show that i.v. administration of siSkp2/Que NPs efficiently accumulates in tumor sites and strongly inhibits the growth of TMU tumors in nude mice. Importantly, the siSkp2/Que NPs do not induce any abnormality in the treated mice, which suggests satisfactory biocompatibility. Collectively, this study describes a tractable siRNA self-assembled strategy for Skp2 silencing, which might be a promising nanodrug to cure multitherapy-resistant advanced prostate cancer.

Microfluidic Preparation of Janus Microparticles With Temperature and pH Triggered Degradation Properties

Based on the phase separation phenomenon in micro-droplets, polymer-lipid Janus particles were prepared on a microfluidic flow focusing chip. Phase separation of droplets was caused by solvent volatilization and Janus morphology was formed under the action of interfacial tension. Because phase change from solid to liquid of the lipid hemisphere could be triggered by physiological temperature, the lipid hemisphere could be used for rapid release of drugs. While the polymer we selected was pH sensitive that the polymer hemisphere could degrade under acidic conditions, making it possible to release drugs in a specific pH environment, such as tumor tissues. Janus particles with different structures were obtained by changing the experimental conditions. To widen the application range of the particles, fatty alcohol and fatty acid-based phase change materials were also employed to prepare the particles, such as 1-tetradecanol, 1-hexadecanol and lauric acid. The melting points of these substances are higher than the physiological temperature, which can be applied in fever triggered drug release or in thermotherapy. The introduction of poly (lactic-co-glycolic acid) enabled the formation of multicompartment particles with three distinct materials. With different degradation properties of each compartment, the particles generated in this work may find applications in programmed and sequential drug release triggered by multiple stimuli.