Advances in targeted delivery of mRNA into immune cells for enhanced cancer therapy.

Messenger RNA (mRNA) therapy has been applied to the treatment of various human diseases including malignant tumors. Increasing evidences have shown that mRNA can enhance the efficacy of cancer immunotherapy by modulating the functions of immune cells and stimulating their activity. However, mRNA is a type of negatively charged biomacromolecules that are susceptible to serum nucleases and cannot readily cross the cell membrane. In the past few decades, various nanoparticles (NPs)-based delivery systems have been rationally designed and developed to facilitate the intracellular uptake and cytosolic delivery of mRNA. More importantly, by means of the specific recognition between the targeting ligands decorated on NP surface and receptors specifically expressed on immune cells, these mRNA delivery systems could be functionalized to target immune cells to further enhance the mRNA-based cancer immunotherapy. In this review, we briefly introduced the advancements of mRNA in cancer therapy, discussed the challenges faced by mRNA delivery, and systematically summarized the recent development in NPs-based mRNA delivery systems targeting various types of immune cells for cancer immunotherapy. The future development of NPs-mediated targeted mRNA delivery and their challenges in clinical translation are also discussed.

LncRNA FAISL Inhibits Calpain 2-Mediated Proteolysis of FAK to Promote Progression and Metastasis of Triple Negative Breast Cancer.

Triple negative breast cancer (TNBC) is the most aggressive subtype in breast tumors. When re-analyzing TCGA breast cancer dataset, we found cell adhesion molecules are highly enriched in differentially expressed genes in TNBC samples, among which Focal Adhesion Kinase (FAK) is most significantly associated with poor survival of TNBC patients. FAK is precisely modulated in the focal adhesion dynamics. To investigate whether lncRNAs regulate FAK signaling, we performed RNA immunoprecipitation sequencing and found FAISL (FAK Interacting and Stabilizing LncRNA) abundantly enriched in FAK-interacting lncRNAs and frequently overexpressed in TCGA TNBC tissues. FAISL promotes TNBC cell adhesion, cytoskeleton spreading, proliferation, and anchor-independent survival. FAISL doesn't affect FAK mRNA but positively regulates FAK protein level by blocking Calpain 2-mediated proteolysis. FAISL interacts with the C-terminus domain of FAK, whereby masks the binding site of Calpain 2 and prevents FAK cleavage. High level of FAISL correlates with FAK expression in tumor tissues and poor prognosis of TNBC patients. A siRNA delivery system targeting FAISL using reduction-responsive nanoparticles effectively inhibits tumor growth and metastasis in TNBC mouse models. Together, these findings uncover a lncRNA-mediated mechanism of regulating FAK proteolysis in the TNBC progression, and highlight the potential of targeting lncRNA FAISL for TNBC treatment.

Nanoparticles (NPs)-mediated lncMALAT1 silencing to reverse cisplatin resistance for effective hepatocellular carcinoma therapy.

Platinum-based chemotherapy has been widely used for clinical cancer treatment, but drug resistance is the main barrier to induce the poor prognosis of cancer patients. Long non-coding RNAs (lncRNAs) have been recognized as a type of new cancer therapeutic targets due to their important role in regulating cancer progression such as drug resistance. However, it is still challenged to effectively intervene the expression of lncRNAs as they are usually located at various subcellular organelles (e.g., nucleus, mitochondrion, and endoplasmic reticulum). We herein developed an endosomal pH-responsive nanoparticle (NP) platform for small interfering RNA (siRNA) and cisplatin prodrug co-delivery and effective cisplatin-resistant hepatocellular carcinoma (HCC) therapy. This co-delivery nanoplatform is comprised of a hydrophilic polyethylene glycol (PEG) shell and a hydrophobic poly (2-(diisopropylamino)ethyl methacrylate) (PDPA) core, in which cisplatin prodrug and electrostatic complexes of nucleus-targeting amphiphilic peptide (NTPA) and siRNA are encapsulated. After intravenous injection and then uptake by tumor cells, the endosomal pH could trigger the dissociation of nanoplatform and enhance the endosomal escape of loaded cisplatin prodrug and NTPA/siRNA complexes via the "proton sponge" effect. Subsequently, the NTPA/siRNA complexes could specifically transport siRNA into the nucleus and efficiently reverse cisplatin resistance via silencing the expression of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (lncMALAT1) mainly localized in the nucleus, ultimately inhibiting the growth of cisplatin-resistant HCC tumor.

Extracellular vesicle surface display of αPD-L1 and αCD3 antibodies via engineered late domain-based scaffold to activate T-cell anti-tumor immunity.

Extracellular vesicles (EVs) are emerging as promising carriers for the delivery of therapeutic biologics. Genetic engineering represents a robust strategy for loading proteins of interest into EVs. Identification of EV-enriched proteins facilitates protein cargo loading efficiency. Many EV-enriched proteins are sorted into EVs via an endosomal sorting complex required for transport (ESCRT)-dependent pathway. In parallel, viruses hijack this EV biosynthesis machinery via conserved late domain motifs to promote egress from host cells. Inspired by the similarity of biogenesis between EVs and viruses, we developed a synthetic, Late domain-based EV scaffold protein that enables the display of a set of single chain variable fragments (scFvs) on the EV surface. We named this scaffold the Late domain-based exosomal antibody surface display platform (LEAP). We applied the LEAP scaffold to reprogramme HEK293T cell-derived EVs to elicit T-cell anti-tumor immunity by simultaneously displaying αPD-L1 and αCD3 scFvs on the EV surface (denoted as αPD-L1×αCD3 bispecific T-cell engaging exosomes, BiTExos). We demonstrated that αPD-L1×αCD3 BiTExos actively redirected T cells to bind to PD-L1+ tumor cells, promoting T-cell activation, proliferation and tumoricidal cytokine production. Furthermore, the αPD-L1×αCD3 BiTExos promoted T-cell infiltration into the tumor microenvironment to mitigate the tumor burden in vivo. Our study suggested that the LEAP scaffold may serve as a platform for EV surface display and could be applied for a broad range of EV-based biomedical applications.

Antibody-Decorated Nanoplatform to Reprogram Macrophage and Block Immune Checkpoint LSECtin for Effective Cancer Immunotherapy.

Repolarizing tumor-associated macrophages (TAMs) into tumor-inhibiting M1 macrophages has been considered a promising strategy for enhanced cancer immunotherapy. However, several immunosuppressive ligands (e.g., LSECtin) can still be highly expressed on M1 macrophages, inducing unsatisfactory therapeutic outcomes. We herein developed an antibody-decorated nanoplatform composed of PEGylated iron oxide nanoparticles (IONPs) and LSECtin antibody conjugated onto the surface of IONPs via the hydrazone bond for enhanced cancer immunotherapy. After intravenous administration, the tumor microenvironment (TME) pH could trigger the hydrazone bond breakage and induce the disassociation of the nanoplatform into free LSECtin antibodies and IONPs. Consequently, the IONPs could repolarize TAMs into M1 macrophages to remodel immunosuppressive TME and provide an additional anticancer effect via secreting tumoricidal factors (e.g., interlukin-12). Meanwhile, the LSECtin antibody could further block the activity of LSECtin expressed on M1 macrophages and relieve its immunosuppressive effect on CD8+ T cells, ultimately leading to significant inhibition of tumor growth.

DNA Damage-Sensitized metal phenolic nanosynergists potentiate Low-Power phototherapy for osteosarcoma therapy.

Non-invasive and efficient photodynamic therapy (PDT) holds great promise to circumvent resistance to traditional osteosarcoma (OS) treatments. Nevertheless, high-power PDT applied in OS often induces photothermogenesis, resulting in normal cells rupture, sustained inflammation and irreversible vascular damage. Despite its relative safety, low-power PDT fails to induce severe DNA damage for insufficient reactive oxygen species (ROS) production. Herein, a non-ROS-dependent DNA damage-sensitizing strategy is introduced in low-power PDT to amplify the therapeutic efficiency of OS, where higher apoptosis is achieved with low laser power. Inspired by the outstanding DNA damage performance of tannic acid (TA), TA-based metal phenolic networks (MPNs) are engineered to encapsulate hydrophobic photosensitizer (purpurin 18) to act as DNA damage-sensitized nanosynergists (TCP NPs). Specially, under low-power laser irradiation, the TCP NPs can boost ROS instantly to trigger mitochondrial dysfunction simultaneously with upregulation of DNA damage levels triggered by TA to reinforce PDT sensitization, evoking potent antitumor effects. In addition, TCP NPs exhibit long-term retention in tumor, greatly benefiting sustained antitumor performances. Overall, this study sheds new light on promoting the sensitivity of low-power PDT by strengthening DNA damage levels and will benefits advanced OS therapy.

Bioactive Nanotherapeutic Ultrasound Contrast Agent for Concurrent Breast Cancer Ultrasound Imaging and Treatment.

Contrast-enhanced ultrasound (CEUS) plays a crucial role in cancer diagnosis. The use of ultrasound contrast agents (UCAs) is inevitable in CEUS. However, current applications of UCAs primarily focus on enhancing imaging quality of ultrasound contrast rather than serving as integrated platforms for both diagnosis and treatment in clinical settings. In this study, a novel UCA, termed NPs-DPPA(C3F8), is innovatively prepared using a combination of nanoprecipitation and ultrasound vibration methods. The DPPA lipid possesses inherent antiangiogenic and antitumor activities, and when combined with C3F8, it functions as a theranostic agent. Notably, the preparation of NPs-DPPA(C3F8) is straightforward, requiring only one hour from raw materials to the final product due to the use of a single material, DPPA. NPs-DPPA(C3F8) exhibits inherent antiangiogenic and biotherapeutic activities, effectively inhibiting triple-negative breast cancer (TNBC) angiogenesis and reducing VEGFA expression both in vitro and in vivo. Clinically, NPs-DPPA(C3F8) enables simultaneous real-time imaging, tumor assessment, and antitumor activity. Additionally, through ultrasound cavitation, NPs-DPPA(C3F8) can overcome the dense vascular walls to increase accumulation at the tumor site and facilitate internalization by tumor cells. The successful preparation of NPs-DPPA(C3F8) offers a novel approach for integrating clinical diagnosis and treatment of TNBC.

Excessive fatty acids activate PRMT5/MDM2/Drosha pathway to regulate miRNA biogenesis and lipid metabolism.

BACKGROUND: Excessive fatty acids in the liver lead to the accumulation of lipotoxic lipids and then cellular stress to further evoke the related disease, like non-alcoholic fatty liver disease (NAFLD). As reported, fatty acid stimulation can cause some specific miRNA dysregulation, which caused us to investigate the relationship between miRNA biogenesis and fatty acid overload. METHODS: Gene expression omnibus (GEO) dataset analysis, miRNA-seq, miRNA cleavage assay, RT-qPCR, western blotting, immunofluorescence and co-immunoprecipitation (co-IP) were used to reveal the change of miRNAs under pathological status and explore the relevant mechanism. High fat, high fructose, high cholesterol (HFHFrHC) diet-fed mice transfected with AAV2/8-shDrosha or AAV2/8-shPRMT5 were established to investigate the in vivo effects of Drosha or PRMT5 on NAFLD phenotype. RESULTS: We discovered that the cleavage of miRNAs was inhibited by analysing miRNA contents and detecting some representative pri-miRNAs in multiple mouse and cell models, which was further verified by the reduction of the Microprocessor activity in the presence of palmitic acid (PA). In vitro, PA could induce Drosha, the core RNase III in the Microprocessor complex, degrading through the proteasome-mediated pathway, while in vivo, knockdown of Drosha significantly promoted NAFLD to develop to a more serious stage. Mechanistically, our results demonstrated that PA can increase the methyltransferase activity of PRMT5 to degrade Drosha through MDM2, a ubiquitin E3 ligase for Drosha. The above results indicated that PRMT5 may be a critical regulator in lipid metabolism during NAFLD, which was confirmed by the knocking down of PRMT5 improved aberrant lipid metabolism in vitro and in vivo. CONCLUSIONS: We first demonstrated the relationship between miRNA dosage and NAFLD and proved that PA can activate the PRMT5-MDM2-Drosha signalling pathway to regulate miRNA biogenesis.

Redox-Responsive Polymeric Nanoparticle for Nucleic Acid Delivery and Cancer Therapy: Progress, Opportunities, and Challenges.

Cancer development and progression of cancer are closely associated with the activation of oncogenes and loss of tumor suppressor genes. Nucleic acid drugs (e.g., siRNA, mRNA, and DNA) are widely used for cancer therapy due to their specific ability to regulate the expression of any cancer-associated genes. However, nucleic acid drugs are negatively charged biomacromolecules that are susceptible to serum nucleases and cannot cross cell membrane. Therefore, specific delivery tools are required to facilitate the intracellular delivery of nucleic acid drugs. In the past few decades, a variety of nanoparticles (NPs) are designed and developed for nucleic acid delivery and cancer therapy. In particular, the polymeric NPs in response to the abnormal redox status in cancer cells have garnered much more attention as their potential in redox-triggered nanostructure dissociation and rapid intracellular release of nucleic acid drugs. In this review, the important genes or signaling pathways regulating the abnormal redox status in cancer cells are briefly introduced and the recent development of redox-responsive NPs for nucleic acid delivery and cancer therapy is systemically summarized. The future development of NPs-mediated nucleic acid delivery and their challenges in clinical translation are also discussed.

Nanomedicine targeting ferroptosis to overcome anticancer therapeutic resistance.

A potential reason for the failure of tumor therapies is treatment resistance. Resistance to chemotherapy, radiotherapy, and immunotherapy continues to be a major obstacle in clinic, resulting in tumor recurrence and metastasis. The major mechanisms of therapy resistance are inhibitions of cell deaths, like apoptosis and necrosis, through drug inactivation and excretion, repair of DNA damage, tumor heterogeneity, or changes in tumor microenvironment, etc. Recent studies have shown that ferroptosis play a major role in therapies resistance by inducing phospholipid peroxidation and iron-dependent cell death. Some ferroptosis inducers in combination with clinical treatment techniques have been used to enhance the effect in tumor therapy. Notably, versatile ferroptosis nanoinducers exhibit an extensive range of functions in reversing therapy resistance, including directly triggering ferroptosis and feedback regulation. Herein, we provide a detailed description of the design, mechanism, and therapeutic application of ferroptosis-mediated synergistic tumor therapeutics. We also discuss the prospect and challenge of nanomedicine in tumor therapy resistance by regulating ferroptosis and combination therapy.

Remodeling of Mitochondrial Metabolism by a Mitochondria-Targeted RNAi Nanoplatform for Effective Cancer Therapy.

Emerging evidence has demonstrated the significant contribution of mitochondrial metabolism dysfunction to promote cancer development and progression. Aberrant expression of mitochondrial genome (mtDNA)-encoded proteins widely involves mitochondrial metabolism dysfunction, and targeted regulation of their expression can be an effective strategy for cancer therapy, which however is challenged due to the protection by the mitochondrial double membrane. Herein, a mitochondria-targeted RNAi nanoparticle (NP) platform for effective regulation of mitochondrial metabolism and breast cancer (BCa) therapy is developed. This nanoplatform is composed of a hydrophilic polyethylene glycol (PEG) shell, a hydrophobic poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) core, and charged-mediated complexes of mitochondria-targeting and membrane-penetrating peptide amphiphile (MMPA) and small interfering RNA (siRNA) embedded in the core. After tumor accumulation and internalization by tumor cells, these NPs can respond to the endosomal pH to expose the MMPA/siRNA complexes, which can specifically transport siRNA into the mitochondria to down-regulate mtDNA-encoded protein expression (e.g., ATP6 and CYB). More importantly, because ATP6 down-regulation can suppress ATP production and enhance reactive oxygen species (ROS) generation to induce mitochondrial damage and mtDNA leakage into tumor tissues, the NPs can combinatorially inhibit tumor growth via suppressing ATP production and repolarizing tumor-associated macrophages (TAMs) into tumor-inhibiting M1-like macrophages by mtDNA.

Nanoparticles (NPs)-mediated Siglec15 silencing and macrophage repolarization for enhanced cancer immunotherapy.

T cell infiltration and proliferation in tumor tissues are the main factors that significantly affect the therapeutic outcomes of cancer immunotherapy. Emerging evidence has shown that interferon-gamma (IFNγ) could enhance CXCL9 secretion from macrophages to recruit T cells, but Siglec15 expressed on TAMs can attenuate T cell proliferation. Therefore, targeted regulation of macrophage function could be a promising strategy to enhance cancer immunotherapy via concurrently promoting the infiltration and proliferation of T cells in tumor tissues. We herein developed reduction-responsive nanoparticles (NPs) made with poly (disulfide amide) (PDSA) and lipid-poly (ethylene glycol) (lipid-PEG) for systemic delivery of Siglec15 siRNA (siSiglec15) and IFNγ for enhanced cancer immunotherapy. After intravenous administration, these cargo-loaded could highly accumulate in the tumor tissues and be efficiently internalized by tumor-associated macrophages (TAMs). With the highly concentrated glutathione (GSH) in the cytoplasm to destroy the nanostructure, the loaded IFNγ and siSiglec15 could be rapidly released, which could respectively repolarize macrophage phenotype to enhance CXCL9 secretion for T cell infiltration and silence Siglec15 expression to promote T cell proliferation, leading to significant inhibition of hepatocellular carcinoma (HCC) growth when combining with the immune checkpoint inhibitor. The strategy developed herein could be used as an effective tool to enhance cancer immunotherapy.

MiR-337-3p improves metabolic-associated fatty liver disease through regulation of glycolipid metabolism.

Epigenetic regulations play crucial roles in the pathogenesis of metabolic-associated fatty liver disease; therefore, elucidating the biological functions of differential miRNAs helps us to understand the pathogenesis. Herein, we discovered miR-337-3p was decreased in patients with NAFLD from Gene Expression Omnibus dataset, which was replicated in various cell and mouse models with lipid disorders. Subsequently, overexpression of miR-337-3p in vivo could ameliorate hepatic lipid accumulation, reduce fasting blood glucose, and improve insulin resistance. Meanwhile, we determined miR-337-3p might influence multiple genes involved in glycolipid metabolism through mass spectrometry detection, bioinformatics analysis, and experimental verification. Finally, we selected HMGCR as a representative example to investigate the molecular mechanism of miR-337-3p regulating these genes, where the seed region of miR-337-3p bound to 3'UTR of HMGCR to inhibit HMGCR translation. In conclusion, we discovered a new function of miR-337-3p in glycolipid metabolism and that might be a new therapeutic target of MAFLD.

LARAI portal provides a safe method for lateral meniscus repair: three-dimensional computed tomography and cadaveric assessment.

BACKGROUND: Lateral, All-Round and All-Inside (LARAI) portal is a viewing or working portal for observing and repairing the lesions of the lateral meniscus. However, there are safety concerns about popliteal artery (PA) injuries during the procedure. This study aimed to assess the safe distance between the trajectory of the LARAI portal and PA. MATERIALS AND METHODS: Both three-dimensional computed tomography (3D-CT) and cadavers were used to simulate the LARAI portal trajectory. In the 3D-CT study, between January 2020 and September 2020, 45 participants who underwent computed tomography angiography were included in the study. The shortest distance from the PA to the simulated trajectory needle (PS) was measured using 3D-CT. Mean -3SD -2 was calculated to assess the safety of the LARAI portal trajectory. If this value was more than zero, the trajectory was considered "safe." In the cadaveric study, lower limbs from seven fresh-frozen cadavers were used to establish the "safe" trajectories of the LARAI portal, and the PS was measured. RESULTS: In the 3D-CT study, the longest PS (P < 0.001) was found 20 mm lateral to the edge of the patellar tendon trajectory at 0 mm from the posterior cruciate ligament (PCL). Safe trajectories were also found 10 mm, 15 mm, and 20 mm lateral to the edge of the patellar tendon at 0 mm from the PCL, as well as the 20 mm lateral to the edge of the patellar tendon at 3 mm from the PCL. The cadaveric study showed that the average PS of all safe trajectories closely adjoined to PCL was greater than 14 mm. CONCLUSIONS: The LARAI portal trajectory in the "figure of four" is safe, and the optimal insertion point is 10-20 mm lateral to the edge of the patellar tendon and closely adjoined to the posterolateral margin of the PCL at knee joint line level. LEVEL OF EVIDENCE: Level IV.

Role of long non-coding RNAs in cancer: From subcellular localization to nanoparticle-mediated targeted regulation.

Long non-coding RNAs (lncRNAs) are a class of RNA transcripts more than 200 nucleotides in length that play crucial roles in cancer development and progression. With the rapid development of high-throughput sequencing technology, a considerable number of lncRNAs have been identified as novel biomarkers for predicting the prognosis of cancer patients and/or therapeutic targets for cancer therapy. In recent years, increasing evidence has shown that the biological functions and regulatory mechanisms of lncRNAs are closely associated with their subcellular localization. More importantly, based on the important roles of lncRNAs in regulating cancer progression (e.g., growth, therapeutic resistance, and metastasis) and the specific ability of nucleic acids (e.g., siRNA, mRNA, and DNA) to regulate the expression of any target genes, much effort has been exerted recently to develop nanoparticle (NP)-based nucleic acid delivery systems for in vivo regulation of lncRNA expression and cancer therapy. In this review, we introduce the subcellular localization and regulatory mechanisms of various functional lncRNAs in cancer and systemically summarize the recent development of NP-mediated nucleic acid delivery for targeted regulation of lncRNA expression and effective cancer therapy.

Nanoparticles (NPs)-mediated lncBCMA silencing to promote eEF1A1 ubiquitination and suppress breast cancer growth and metastasis.

Long non-coding RNAs (lncRNAs) play an important role in cancer metastasis. Exploring metastasis-associated lncRNAs and developing effective strategy for targeted regulation of lncRNA function in vivo are of utmost importance for the treatment of metastatic cancer, which however remains a big challenge. Herein, we identified a new functional lncRNA (denoted lncBCMA), which could stabilize the expression of eukaryotic translation elongation factor 1A1 (eEF1A1) via antagonizing its ubiquitination to promote triple-negative breast cancer (TNBC) growth and metastasis. Based on this regulatory mechanism, an endosomal pH-responsive nanoparticle (NP) platform was engineered for systemic lncBCMA siRNA (siBCMA) delivery. This NPs-mediated siBCMA delivery could effectively silence lncBCMA expression and promote eEF1A1 ubiquitination, thereby leading to a significant inhibition of TNBC tumor growth and metastasis. These findings show that lncBCMA could be used as a potential biomarker to predict the prognosis of TNBC patients and NPs-mediated lncBCMA silencing could be an effective strategy for metastatic TNBC treatment.

MiR-552-3p Regulates Multiple Fibrotic and Inflammatory genes Concurrently in Hepatic Stellate Cells Improving NASH-associated Phenotypes.

Non-alcoholic steatohepatitis (NASH) is a chronic liver disease characterized by hepatic steatosis, inflammation, and progressive fibrosis. Our previous study demonstrated that microRNA-552-3p (miR-552-3p) was down-regulated in the livers of patients with NASH and alleviated hepatic glycolipid metabolic disorders. However, whether miR-552-3p affects NASH progression remains unclear. In this current study, we found that hepatic miR-552-3p expression was negatively correlated with the degree of liver fibrosis and inflammation of NASH patients. Interestingly, the level of miR-552-3p was decreased during hepatic stellate cell (HSC) activation in vitro. Overexpression of miR-552-3p could not only inhibit the expression of fibrotic and inflammatory genes, but also restrain the activation of TGF-ß1/Smad3 signaling pathway by down-regulating the expression of TGFBR2 and SMAD3 in HSCs, finally suppressing HSC activation. More importantly, overexpression of miR-552-3p ameliorated liver fibrosis and inflammation in two murine models: high fat/high fructose/high cholesterol diet-induced NASH model and carbon tetrachloride (CCl4)-treated liver fibrosis model. In conclusion, miR-552-3p plays a crucial role in the pathogenesis of NASH by limiting multiple fibrotic and inflammatory pathways in HSCs, which may shed light on its therapeutic potential in NASH.

Remodeling Serine Synthesis and Metabolism via Nanoparticles (NPs)-Mediated CFL1 Silencing to Enhance the Sensitivity of Hepatocellular Carcinoma to Sorafenib.

Tyrosine kinase inhibitors represented by sorafenib are the first-line treatment for hepatocellular carcinoma (HCC), but the low response rate of HCC patient has become a clinical pain-point. Emerging evidences have revealed that metabolic reprogramming plays an important role in regulating the sensitivity of tumor cells to various chemotherapeutics including sorafenib. However, the underlying mechanisms are very complex and are not fully elucidated. By comparing the transcriptome sequencing data of sorafenib-sensitive and -insensitive HCC patients, it is revealed that cofilin 1 (CFL1) is highly expressed in the tumor tissues of sorafenib-insensitive HCC patients and closely correlated with their poor prognosis. Mechanically, CFL1 can promote phosphoglycerate dehydrogenase transcription and enhance serine synthesis and metabolism to accelerate the production of antioxidants for scavenging the excessive reactive oxygen species induced by sorafenib, thereby impairing the sorafenib sensitivity of HCC. To translate this finding and consider the severe side effects of sorafenib, a reduction-responsive nanoplatform for systemic co-delivery of CFL1 siRNA (siCFL1) and sorafenib is further developed, and its high efficacy in inhibiting HCC tumor growth without apparent toxicity is demonstrated. These results indicate that nanoparticles-mediated co-delivery of siCFL1 and sorafenib can be a new strategy for the treatment of advanced HCC.

Nanoparticles (NPs)-mediated systemic mRNA delivery to reverse trastuzumab resistance for effective breast cancer therapy.

Monoclonal antibody-based therapy has achieved great success and is now one of the most crucial therapeutic modalities for cancer therapy. The first monoclonal antibody authorized for treating human epidermal growth receptor 2 (HER2)-positive breast cancer is trastuzumab. However, resistance to trastuzumab therapy is frequently encountered and thus significantly restricts the therapeutic outcomes. To address this issue, tumor microenvironment (TME) pH-responsive nanoparticles (NPs) were herein developed for systemic mRNA delivery to reverse the trastuzumab resistance of breast cancer (BCa). This nanoplatform is comprised of a methoxyl-poly (ethylene glycol)-b-poly (lactic-co-glycolic acid) copolymer with a TME pH-liable linker (Meo-PEG-Dlink m -PLGA) and an amphiphilic cationic lipid that can complex PTEN mRNA via electrostatic interaction. When the long-circulating mRNA-loaded NPs build up in the tumor after being delivered intravenously, they could be efficiently internalized by tumor cells due to the TME pH-triggered PEG detachment from the NP surface. With the intracellular mRNA release to up-regulate PTEN expression, the constantly activated PI3K/Akt signaling pathway could be blocked in the trastuzumab-resistant BCa cells, thereby resulting in the reversal of trastuzumab resistance and effectively suppress the development of BCa.